Management of preschool recurrent wheezing and asthma: a phenotype-based approach.
The purpose of this review is to summarize the recent evidence on the management of preschool children with wheezing and asthma, and to propose a phenotype-based approach to the management of these children. Recent studies have begun to identify populations of preschool children that are likely to benefit from inhaled corticosteroids (ICS) therapy and defined ICS regimens: daily ICS in preschool children with persistent asthma, and pre-emptive high-dose intermittent ICS among preschool children with intermittent disease reduce the risk of exacerbation. In addition, among preschool children with mild persistent asthma, the presence of aeroallergen sensitivity and/or blood eosinophil counts of 300/μL or greater are predictors of good response to daily ICS therapy. Other studies identified intermittent azithromycin as a therapy to prevent, and potentially to treat, acute exacerbations.The uncertainty of the role of oral corticosteroids (OCS) as a therapy for acute exacerbations continues, as a recent meta-analysis showed that OCS did not prevent hospitalizations or urgent visits, and did not reduce the need for additional courses of OCS. Whereas previous epidemiologic studies suggested acetaminophen may increase risk of exacerbations, a clinical trial clearly demonstrated acetaminophen use, compared to ibuprofen use,does not increase exacerbation risk among preschool children with mild-persistent asthma. Recent studies have shown potential for phenotypic-driven therapies for the management of preschool children with asthma. Targeting airway bacteria has emerged as a promising therapeutic approach, but its effect on antibiotic resistance still needs to be investigated. Finally, more studies are required to evaluate if oral corticosteroids provide any benefits for acute episodic wheeze.


Mechanism for shifting the phase of a circadian rhythm by serotonin: involvement of cAMP.
Serotonin (5-hydroxytryptamine, 5-HT) shifts the phase of the circadian rhythm in the eye of Aplysia. We have examined the role of cAMP in mediating the effects of 5-HT on the rhythm. The phase shifts produced by 5-HT are mimicked by treatments that should increase intracellular levels of cAMP. An analogue of cAMP-8-benzylthio-cAMP, advanced and delayed the rhythm at phases in which 5-HT had similar effects on the rhythm. In addition, two phosphodiesterase inhibitors, Ro-20-1724 and papaverine, caused advance phase shifts where 5-HT advances the rhythm. The phosphodiesterase inhibitors Ro-20-1724 and 3-isobutyl-1-methylxanthine each potentiated the effect of subthreshold doses of 5-HT on the rhythm. The effects of 5-HT and 8-benzylthio-cAMP on the rhythm were nonadditive, indicating that 5-HT and 8-benzylthio-cAMP affect the rhythm through a common pathway. Finally, 5-HT produced large changes (13-fold) in the levels of cAMP in the eye. These results indicate that cAMP mediates the effect of 5-HT on the rhythm. There are two possible roles for cAMP in the circadian system. Either the cAMP system is an intracellular step in an entrainment pathway or it is part of the biological clock. Because 5-HT, 8-benzylthio-cAMP, and three phosphodiesterase inhibitors inhibit impulses from the eye, cAMP may also mediate the inhibition produced by 5-HT, or it might be involved in regulating the frequency of spontaneous impulses throughout the day.


Evidence-based recommendations for the management of anterior cruciate ligament (ACL) rupture.
Anterior cruciate ligament (ACL) rupture occurs most commonly in young and active individuals and can have negative long-term physical and psychological impacts. The diagnosis is made with a combination of patient's history, clinical examination, and, if appropriate, magnetic resonance imaging. The objectives of management are to restore knee function, address psychological barriers to activity participation, prevent further injury and osteoarthritis, and optimize long-term quality of life. The three main treatment options for ACL rupture are (1) rehabilitation as first-line treatment (followed by ACL reconstruction (ACLR) in patients, who develop functional instability), (2) ACLR and post-operative rehabilitation as the first-line treatment, and (3) pre-operative rehabilitation followed by ACLR and post-operative rehabilitation. We provide practical recommendations for informing and discussing management options with patients, and describe patient-related factors associated with a worse ACL-rupture outcome. Finally, we define evidence-based rehabilitation and present phase-specific rehabilitation recommendations and criteria to inform return to sport decisions.


Extracellular vimentin: Battle between the devil and the angel.
Vimentin, an intracellular cytoskeletal protein, can be secreted by various cells in response to conditions such as injury, stress, senescence, and cancer. Once vimentin is secreted outside of the cell, it is called extracellular vimentin. This extracellular vimentin is significantly involved in pathological conditions, particularly in the areas of viral infection, cancer, immune response, and wound healing. The effects of extracellular vimentin can be either positive or negative, for example it can enhance axonal repair but also mediates SARS-CoV-2 infection. In this review, we categorize the functional implications of extracellular vimentin based on its localization outside the cell. Specifically, we classify extracellular vimentin into two distinct forms: surface vimentin, which remains bound to the cell surface, and secreted vimentin, which refers to the free form that is completely released outside the cell. Overall, extracellular vimentin has a dual nature that encompasses both beneficial and detrimental effects on the functionality of cells, organs and whole organisms. Here, we summarize its effects in viral infection, cancer, immune response and wound healing. We find that surface vimentin is often associated with negative consequences, whereas secreted vimentin manifests predominantly with positive influences. We found that the observed effects of extracellular vimentin strongly depend on the specific circumstances under which its expression occurs in cells.


Design, synthesis, and antioxidant potency of novel alpha-tocopherol analogues in isolated membranes and intact cells.
In this study, we have designed novel chromanyl derivatives that share with alpha-tocopherol a chromanyl head but differ in the lateral chain in: (i) length and saturation (FEBL-45, 50, 70), (ii) position of double bonds in Z or E (FEBL-50 and 53 and their respective 6-chromanyl methyl derivatives FEBL-161 and 162), or (iii) presence of additional antioxidant molecules, such as the catechol compound hydroxytyrosol (FEBL-80) or dopamine (FEBL-82, 95). The efficiency of these compounds in preventing free-radical-induced oxidative stress was investigated in isolated membranes as well as intact cells. The results of this study clearly show that all compounds synthesized were active in: (i) inhibiting AAPH- or tert-BOOH-induced lipid peroxidation in microsomes and (ii) preventing H2O2-induced ROS production, cell damage, and heat-shock protein expression in immortalized RAT-1 fibroblasts. Such effects were dose- and time-dependent. Independent of the kind of pro-oxidant used, differences in the antioxidant potency of these compounds were found in relation to the chemical structure with respect to the natural alpha-tocopherol: (1) The concomitant presence of a chromanyl head and an additional aromatic ring markedly increased the antioxidant potency of the molecule. In particular, FEBL-82 and FEBL-95, resulting from the molecular combination of trolox and dopamine, were much more potent than alpha-tocopherol, alpha-tocotrienol, and the other synthetic compounds. Moreover, they were also more potent than trolox and dopamine, used alone or in combination, suggesting synergistic cooperative interactions in the molecule between chromanyl and catechol moieties. (2) The length of the side chain affected the antioxidant properties of the molecule: FEBL-70, which displays a bulky squalene side chain, was less effective than the natural alpha-tocotrienol and the synthetic FEBL-45 and FEBL-50. (3) The presence of polyunsaturated double bonds in the side chain in the Z configuration (FEBL-53, FEBL-162) increased the antioxidant potency of the molecule with respect to the E configuration (FEBL-50, FEBL-161).


Superconducting spin reorientation in spin-triplet multiple superconducting phases of UTe2.
Superconducting (SC) state has spin and orbital degrees of freedom, and spin-triplet superconductivity shows multiple SC phases because of the presence of these degrees of freedom. However, the observation of spin-direction rotation occurring inside the SC state (SC spin rotation) has hardly been reported. Uranium ditelluride, a recently found topological superconductor, exhibits various SC phases under pressure: SC state at ambient pressure (SC1), high-temperature SC state above 0.5 gigapascal (SC2), and low-temperature SC state above 0.5 gigapascal (SC3). We performed nuclear magnetic resonance (NMR) and ac susceptibility measurements on a single-crystal uranium ditelluride. The b axis spin susceptibility remains unchanged in SC2, unlike in SC1, and decreases below the SC2-SC3 transition with spin modulation. These unique properties in SC3 arise from the coexistence of two SC order parameters. Our NMR results confirm spin-triplet superconductivity with SC spin parallel to b axis in SC2 and unveil the remaining of spin degrees of freedom in SC uranium ditelluride.


Coping and thought suppression as predictors of suicidal ideation in depressed older adults with personality disorders.
Suicide rates are higher among older adults than any other age group and suicidal ideation is one of the best predictors of completed suicide in older adults. Despite this, few studies have evaluated predictors of suicidal ideation and other correlates of death by suicide (e.g. hopelessness) among older adults. Even fewer studies on this topic have been conducted among samples characterized as poor responders to treatments (e.g. depressed individuals with co-occurring personality disorder). The purpose of this study was to examine coping styles and thought suppression as predictors of a suicide risk composite score in a sample of depressed older adults with co-occurring personality disorders. Based on the extant literature, it was hypothesized that maladaptive coping (i.e. emotional and avoidance coping) and chronic thought suppression would significantly predict suicide risk. The results of this study indicated that elevated emotional coping and thought suppression were associated with increased suicide risk. Contrary to hypotheses, lower avoidance coping was associated with increased risk, although this finding is moderated by Axis II diagnosis Thus, treatments that focus on decreasing emotional coping and chronic thought suppression may result in decreased suicidal ideation and hopelessness for older adults with depression and Axis II pathology.


Inhibition of STAT3 promotes the efficacy of adoptive transfer therapy using type-1 CTLs by modulation of the immunological microenvironment in a murine intracranial glioma.
A variety of cancers, including malignant gliomas, show aberrant activation of STAT3, which plays a pivotal role in negative regulation of antitumor immunity. We hypothesized that inhibition of STAT3 signals would improve the efficacy of T cell adoptive transfer therapy by reversal of STAT3-induced immunosuppression in a murine GL261 intracranial glioma model. In vitro treatment of GL261 cells with JSI-124, a STAT3 inhibitor, reversed highly phosphorylated status of STAT3. Systemic i.p. administration of JSI-124 in glioma-bearing immunocompetent mice, but not athymic mice, resulted in prolonged survival, suggesting a role of adaptive immunity in the antitumor effect. Furthermore, JSI-124 promoted maturation of tumor-infiltrating CD11c(+) dendritic cells and activation of tumor-conditioned cytotoxic T cells, enhanced dendritic cells and GL261 production of CXCL-10, a critical chemokine for attraction of Tc1 cells. When i.p. JSI-124 administration was combined with i.v. transfer of Pmel-I mouse-derived type-1 CTLs (Tc1), glioma-bearing mice exhibited prolonged survival compared with i.p. JSI-124 or i.v. Tc1 therapy alone. Flow cytometric analyses of brain infiltrating lymphocytes revealed that JSI-124-treatment enhanced the tumor-homing of i.v. transferred Tc1 cells in a CXCL-10-dependent fashion. Systemic JSI-124 administration also up-regulated serum IL-15 levels, and promoted the persistence of transferred Tc1 in the host. These data suggest that systemic inhibition of STAT3 signaling can reverse the suppressive immunological environment of intracranial tumor bearing mice both systemically and locally, thereby promoting the efficacy of adoptive transfer therapy with Tc1.


Cryptococcus Neoformans Meningitis Cases Among China's HIV-Infected Population may have been Severely Under-Reported.
Cryptococcal meningitis (CM) is the leading fungal infection of the central nervous system. Globally, most CM cases have been reported from patients with compromised immunities, especially those infected with HIV. However, reports from China have shown that most CM infections were from HIV-negative, immunocompetent hosts. Here, we reviewed the published reports and found those studies were almost exclusively based on patients from hospitals associated with Chinese universities but not from specialized infectious diseases hospitals where most Chinese HIV-infected patients have been treated. Thus, we believe CM cases among China's HIV-infected population may have been severely under-reported. Analyses of CM cases in specialized infectious diseases hospitals are needed to identify the true epidemiological pattern of CM in China.


Gene networks underlying the early regulation of Paraburkholderia phytofirmans PsJN induced systemic resistance in Arabidopsis.
Plant defense responses to biotic stresses are complex biological processes, all governed by sophisticated molecular regulations. Induced systemic resistance (ISR) is one of these defense mechanisms where beneficial bacteria or fungi prime plants to resist pathogens or pest attacks. In ISR, the defense arsenal in plants remains dormant and it is only triggered by an infection, allowing a better allocation of plant resources. Our group recently described that the well-known beneficial bacterium Paraburkholderia phytofirmans PsJN is able to induce Arabidopsis thaliana resistance to Pseudomonas syringae pv. tomato (Pst) DC3000 through ISR, and that ethylene, jasmonate and salicylic acid are involved in this protection. Nevertheless, the molecular networks governing this beneficial interaction remain unknown. To tackle this issue, we analyzed the temporal changes in the transcriptome of PsJN-inoculated plants before and after being infected with Pst DC3000. These data were used to perform a gene network analysis to identify highly connected transcription factors. Before the pathogen challenge, the strain PsJN regulated 405 genes (corresponding to 1.8% of the analyzed genome). PsJN-inoculated plants presented a faster and stronger transcriptional response at 1-hour post infection (hpi) compared with the non-inoculated plants, which presented the highest transcriptional changes at 24 hpi. A principal component analysis showed that PsJN-induced plant responses to the pathogen could be differentiated from those induced by the pathogen itself. Forty-eight transcription factors were regulated by PsJN at 1 hpi, and a system biology analysis revealed a network with four clusters. Within these clusters LHY, WRKY28, MYB31 and RRTF1 are highly connected transcription factors, which could act as hub regulators in this interaction. Concordantly with our previous results, these clusters are related to jasmonate, ethylene, salicylic, acid and ROS pathways. These results indicate that a rapid and specific response of PsJN-inoculated plants to the virulent DC3000 strain could be the pivotal element in the protection mechanism.


Clinical Performance of a Gene-Based Machine Learning Classifier in Assessing Risk of Developing OUD in Subjects Taking Oral Opioids: A Prospective Observational Study.
To reduce the incidence of Opioid Use Disorder (OUD), multiple guidelines recommend assessing the risk of OUD prior to prescribing oral opioids. Although subjective risk assessments are available to help classify subjects at risk for OUD, we are aware of no clinically validated objective risk assessment tools. An objective risk assessment based on genetics may help inform shared decision-making prior to prescribing short-duration oral opioids. A multicenter, observational cohort of adults exposed to prescription oral opioids for 4-30 days was conducted to determine the performance of an OUD classifier derived from machine learning (ML). From this cohort, the demographics of the U.S. adult opioid-prescribed population were used to create a blinded, random, representative group of subjects (n=385) for analysis to accurately estimate the performance characteristics in the intended use population. Genotyping was performed via a qualitative SNP microarray on DNA extracted from buccal samples. In the study subjects, the classifier demonstrated 82.5% sensitivity (95% confidence intervals: 76.1%-87.8%) and 79.9% specificity (73.7-85.2%), with no statistically significant differences in clinical performance observed based on gender, age, length of follow-up from opioid exposure, race, or ethnicity. This study demonstrates an ML classifier may provide additional objective information regarding a patient's risk of developing OUD. This information may enable subjects and healthcare providers to make more informed decisions when considering the use of oral opioids.


¹⁸F-NaF PET/CT and ¹¹C-Choline PET/CT for the initial detection of metastatic disease in prostate cancer: overview and potential utilization.
With the rapid increase in new therapies to treat advanced prostate cancer, improved diagnosis tools are necessary to help refine patient management throughout the entire disease course. Many radiopharmaceuticals, most of which are imaged using positron emission tomography/computed tomography (PET/CT), are in development; two of these newer radiopharmaceuticals are ¹⁸F-sodium fluoride (NaF) and radiolabeled choline. Compared with traditional imaging, use ¹⁸F-NaF has been shown to improve sensitivity and specificity, and radiolabeled choline has been shown to detect recurrent and metastatic disease earlier. We briefly review these two imaging technologies and provide potential utilization strategies based on available data.


Impact of De-Identification on Clinical Text Classification Using Traditional and Deep Learning Classifiers.
Clinical text de-identification enables collaborative research while protecting patient privacy and confidentiality; however, concerns persist about the reduction in the utility of the de-identified text for information extraction and machine learning tasks. In the context of a deep learning experiment to detect altered mental status in emergency department provider notes, we tested several classifiers on clinical notes in their original form and on their automatically de-identified counterpart. We tested both traditional bag-of-words based machine learning models as well as word-embedding based deep learning models. We evaluated the models on 1,113 history of present illness notes. A total of 1,795 protected health information tokens were replaced in the de-identification process across all notes. The deep learning models had the best performance with accuracies of 95% on both original and de-identified notes. However, there was no significant difference in the performance of any of the models on the original vs. the de-identified notes.


[Tracheotomy or intubation? Problems with long-term intensive care patients].
Three groups of probands were established among 77 long-term intensive care patients. Group I comprised cases intubated for more than 7 days, group II underwent tracheotomy after a variable time of intubation, and group III were tracheotomised immediately. All complications were severalfold more frequent in patients with hypercatabolic underlying disease than in those with less severe underlying disease. Long-term intubation led generally to laryngeal damage after one week and increased frequency of pneumonia after two weeks. Patients with tracheotomy after an interval showed frequent pneumonias only after one month. Inflammatory changes of trachea, bronchi, and tracheostoma with the appropriate consequences were frequent. Lower tracheal stenoses occurred in approximately 10% of cases in group II. The lowest complication rate was observed in patients tracheotomised immediately. Patients with hypercatabolic disease without prospects for improvement in the near future should be tracheotomised as early as possible. Tracheotomy can be postponed for up to three weeks if regression is to be expected in that time. In diseases without rapid physical deterioration the indication for tracheotomy can be postponed for six weeks.


In vitro and in vivo susceptibility of Candida keratitis to topical polyenes.
The susceptibility of Candida albicans to topical amphotericin B and natamycin was evaluated in a model of stromal keratitis in Dutch-belted rabbits and compared with minimal inhibitory concentrations in vitro. Treatment was delayed 24 hr to allow invasive disease to occur and was then continued for 5 days. Ten strains of Candida albicans comprised the test panel. For amphotericin B, the minimal inhibitory concentration (MIC) by tube dilution classified the same strains as resistant or susceptible as did the in vivo response. A dose-response was observed with different concentrations of the drug. For natamycin, the MIC misclassified two strains. The rate of administration of natamycin required in this model was much higher than for amphotericin B, a therapeutic effect being observed with natamycin only when the drug was administered every 30 min during the in vivo efficacy and in vitro susceptibility with these strains is in agreement with that observed in the authors' previous studies using a model of immediate treatment.


IL-15 enhances immune functions during HIV infection.
IL-15, a new cytokine primarily produced by macrophages, has been shown to exhibit several functional properties shared with IL-2. Treatment of PBMC from HIV-infected patients with IL-15 resulted in an increase in NK cell cytotoxicity to levels similar to those of untreated PBMC from healthy donors. This effect is independent of several well-characterized regulatory cytokines, as it is not prevented by Abs that neutralize IFNs, TNF-alpha, IL-2, or IL-12. Enhanced cytotoxicity was accompanied by a significant increase in expression of cytotoxic granules. IL-15 enhanced the proliferative ability in both controls and HIV-seropositive in response to mitogen and recall Ags. Although the addition of IL-15 has a preventive effect on the appearance of spontaneous cell death, this effect was not seen during mitogen-induced apoptosis. The production of IL-15 by PBMC from patients in response to Staphylococcus aureus Cowan strain 1 appeared heterogeneous and was not negatively regulated by cytokines that inhibited IL-12 production. No correlation was found between in vitro HIV infection and IL-15 production, as viral infection had no effect on the ability of monocytes to produce IL-15 in response to S. aureus. Interestingly IL-15 restored the deficient production of IL-12 by PBMC from HIV+ people and had no major effect on modulating viral expression in latently infected cell lines or PBMC from naturally infected people. Taken together, these results suggest a potent immunoregulatory role of IL-15 during HIV infection.


Overexpression of FGF-2 modulates fiber cell differentiation and survival in the mouse lens.
During mammalian embryogenesis, the ocular lens forms through a temporally and spatially regulated pattern of differentiation which is thought to be coordinated at least in part by the FGF-1 and FGF-2 members of the fibroblast growth factor (FGF) family. Previous transgenic experiments in which FGF-1 or dominant negative FGF receptors were overexpressed in the lens indicated that FGF-1 could induce differentiation while differentiated lens cells rely upon FGF signaling for their survival. In this study, we asked if the 17.5 kDa FGF-2 protein was capable of inducing differentiation of lens cells in transgenic mice. Unexpectedly, differentiation was inhibited by lens-specific expression of a transgene encoding a secreted form of the 17.5 kDa bovine FGF-2 protein under the transcriptional control of the murine alphaA-crystallin promoter (alphaAIgFGF-2 transgenic mice). To address the possibility that FGF-2 functions as a modulator of fiber cell survival, alphaAIgFGF-2 transgenic mice were crossed to transgenic mice exhibiting extensive apoptosis in the lens due to the functional inactivation of the retinoblastoma protein (alphaAE7 transgenic mice). The level of apoptosis in the lenses of double transgenic mice was substantially reduced as compared to the level in lenses from alphaAE7 only mice. These studies indicate that FGF-2 can act as a modulator of the later stages of differentiation including fiber cell survival. Additionally, they imply that control of lens development by FGFs is a complex process in which FGF-1 and FGF-2 play distinct roles.


Evaluation of six TaqMan RT-rtPCR kits on two thermocyclers for the reliable detection of rabies virus RNA.
Rabies is diagnosed postmortem in animals, based on tests prescribed by the World Organization for Animal Health (OIE), such as the fluorescent antibody test, the direct rapid immunohistochemistry test, or pan-lyssavirus PCR assays. Several reverse-transcription real-time PCR (RT-rtPCR) methods have been developed and validated for rapid and accurate detection of lyssaviruses. We evaluated the performance of 6 TaqMan RT-rtPCR kits using different commercial master mixes and 2 real-time thermocyclers. Changing the master mix overall did not influence the TaqMan RT-rtPCR performance, regardless of the thermocycler used. The limits of detection at the 95% confidence level were 18.1-25.8 copies/µL for the Rotor-Gene Q MDx thermocycler and 16.7-21.5 for the Mx3005P thermocycler. Excellent repeatability was demonstrated for rabies virus (RABV) RNA samples of 100, 50, and 25 copies/µL regardless of the thermocycler used. RABV field samples ( n = 35) isolated worldwide gave positive results using the most efficient of the 6 kits tested, with a copy number of 6.03 × 102 to 6.78 × 107 RNA copies per reaction. The TaqMan RT-rtPCR assay provides sensitive and rapid amplification of RABV RNA.


Critical electric field strengths of onion tissues treated by pulsed electric fields.
The impact of pulsed electric fields (PEF) on cellular integrity and texture of Ranchero and Sabroso onions (Allium cepa L.) was investigated. Electrical properties, ion leakage rate, texture, and amount of enzymatically formed pyruvate were measured before and after PEF treatment for a range of applied field strengths and number of pulses. Critical electric field strengths or thresholds (E(c)) necessary to initiate membrane rupture were different because dissimilar properties were measured. Measurement of electrical characteristics was the most sensitive method and was used to detect the early stage of plasma membrane breakdown, while pyruvate formation by the enzyme alliinase was used to identify tonoplast membrane breakdown. Our results for 100-μs pulses indicate that breakdown of the plasma membrane occurs above E(c)= 67 V/cm for 10 pulses, but breakdown of the tonoplast membrane is above either E(c)= 200 V/cm for 10 pulses or 133 V/cm for 100 pulses. This disparity in field strength suggests there may be 2 critical electrical field strengths: a lower field strength for plasma membrane breakdown and a higher field strength for tonoplast membrane breakdown. Both critical electric field strengths depended on the number of pulses applied. Application of a single pulse at an electric field up to 333 V/cm had no observable effect on any measured properties, while significant differences were observed for n≥10. The minimum electric field strength required to cause a measurable property change decreased with the number of pulses. The results also suggest that PEF treatment may be more efficient if a higher electric field strength is applied for a fewer pulses.


Transition metal-mediated intramolecular [2+2+2] cycloisomerizations of cyclic triynes and enediynes.
[reaction: see text] Nitrogen-containing 15-membered triacetylenic macrocycles known as 1,6,11-tris(arylsulfonyl)-1,6,11-triazacyclopentadeca-3,8,13-triynes (1) and enediynic macrocycles called 1,6,11-tris(arylsulfonyl)-1,6,11-triazacyclopentadeca-3-ene-8,13-diynes (4 and 5) were satisfactorily prepared. [2+2+2] cycloisomerization processes catalyzed by transition metals were tested in the above-mentioned macrocycles. Readily available and familiar cyclotrimerization precatalysts were examined for efficiency. Among them, the RhCl(CO)(PPh(3))(2) complex was found to catalyze the cycloisomerization reaction giving the desired cycloadducts in high yields.


Monte Carlo modelling of external radiotherapy photon beams.
An essential requirement for successful radiation therapy is that the discrepancies between dose distributions calculated at the treatment planning stage and those delivered to the patient are minimized. An important component in the treatment planning process is the accurate calculation of dose distributions. The most accurate way to do this is by Monte Carlo calculation of particle transport, first in the geometry of the external or internal source followed by tracking the transport and energy deposition in the tissues of interest. Additionally, Monte Carlo simulations allow one to investigate the influence of source components on beams of a particular type and their contaminant particles. Since the mid 1990s, there has been an enormous increase in Monte Carlo studies dealing specifically with the subject of the present review, i.e., external photon beam Monte Carlo calculations, aided by the advent of new codes and fast computers. The foundations for this work were laid from the late 1970s until the early 1990s. In this paper we will review the progress made in this field over the last 25 years. The review will be focused mainly on Monte Carlo modelling of linear accelerator treatment heads but sections will also be devoted to kilovoltage x-ray units and 60Co teletherapy sources.


Visceral obesity determined in routine preoperative CT scans predicts risk of postoperative burst abdomen.
Burst abdomen (BA) remains a severe postoperative complication after abdominal surgery. Obesity is a known risk factor for postoperative complications but objective parameters such as body mass index fail to predict BA after abdominal surgery. In recent literature, CT-derived body composition assessment could predict obesity-related diseases and surgical site infections. We report data from the institutional wound register, comparing patients with BA to a subgroup of patients without BA. The CT images were evaluated for intraabdominal and subcutaneous fat tissues. Univariate and multivariate risk factor analysis was performed in order to evaluate CT-derived obesity parameters as risk factor for BA. 92 patients with BA were compared to 32 controls. Patients with BA had significantly more visceral obesity (VO; p < 0.001) but less subcutaneous obesity (SCO) on CT scans. VO and SCO both were positively correlated with BMI (r = 0.452 and 0.572) but VO and SCO were inversely correlated (r = -0.189). Multivariate analysis revealed VO as significant risk factor for postoperative BA (OR 1.257; 95% CI 1.084-1.459; p = 0.003). Our analysis of patients with postoperative BA revealed VO as major risk factor for postoperative BA. Thus, preoperative CT scans gives valuable information on possible risk stratification.


A H-bond strategy to develop acid-resistant photoswitchable rhodamine spirolactams for super-resolution single-molecule localization microscopy.
Rhodamine spirolactam based photoswitches have been extensively applied in super-resolution single-molecule localization microscopy (SMLM). However, the ring-opening reactions of spirolactams are cross-sensitive to acid, limiting their photoswitch use to neutral pH conditions. In addition, the ring-closing reactions of spirolactams are environment-sensitive and slow (up to hours), virtually making rhodamine spirolactams caged fluorescent dyes instead of reversible photoswitches in SMLM. Herein, by introducing hydrogen bonds to stabilize spirolactams, we report a series of acid-resistant rhodamine spirolactams with accelerated ring-closing reactions from fluorescent xanthyliums to non-fluorescent spirolactams, endowing them with good photoswitchable properties even in acidic environments. By further substitution of 6-phenylethynyl naphthalimide on the spirolactam, we shifted the photoactivation wavelength into the visible region (>400 nm). Subsequently, we have successfully applied these dyes in labeling and imaging the cell surface of Bacillus subtilis at pH 4.5 using SMLM.


Directed intermixing in multicomponent self-assembling biomaterials.
The noncovalent coassembly of multiple different peptides can be a useful route for producing multifunctional biomaterials. However, to date, such materials have almost exclusively been investigated as homogeneous self-assemblies, having functional components uniformly distributed throughout their supramolecular structures. Here we illustrate control over the intermixing of multiple different self-assembling peptides, in turn providing a simple but powerful means for modulating these materials' mechanical and biological properties. In β-sheet fibrillizing hydrogels, significant increases in stiffening could be achieved using heterobifunctional cross-linkers by sequestering peptides bearing different reactive groups into distinct populations of fibrils, thus favoring interfibril cross-linking. Further, by specifying the intermixing of RGD-bearing peptides in 2-D and 3-D self-assemblies, the growth of HUVECs and NIH 3T3 cells could be significantly modulated. This approach may be immediately applicable toward a wide variety of self-assembling systems that form stable supramolecular structures.


Care during the third stage of labour: a postal survey of UK midwives and obstetricians.
There are two approaches to care during the third stage of labour: Active management includes three components: administration of a prophylactic uterotonic drug, cord clamping and controlled cord traction. For physiological care, intervention occurs only if there is clinical need. Evidence to guide care during the third stage is limited and there is variation in recommendations which may contribute to differences in practice. This paper describes current UK practice during the third stage of labour. A postal survey of 2230 fellows and members of the Royal College of Obstetricians and Gynaecologists (RCOG) and 2400 members of the Royal College of Midwives was undertaken. Respondents were asked about care during the third stage of labour, for vaginal and caesarean births and their views on the need for more evidence to guide care in the third stage. The data were analysed in Excel and presented as descriptive statistics. 1189 (53%) fellows and members of the RCOG and 1702 (71%) midwives responded, of whom 926 (78%) and 1297 (76%) respectively had conducted or supervised births in the last year. 93% (863/926) of obstetricians and 73% (942/1297) of midwives report 'always or usually' using active management. 66% (611/926) of obstetricians and 33% (430/1297) of midwives give the uterotonic drug with delivery of the anterior shoulder; this was intramuscular Syntometrine(R) for 79% (728/926) and 86% (1118/1293) respectively. For term births, 74% (682/926) of obstetricians and 41% (526/1297) of midwives clamp the cord within 20 seconds, as do 57% (523/926) and 55% (707/1297) for preterm births. Controlled cord traction was used by 94% of both obstetricians and midwives. For caesarean births, intravenous oxytocin was the uterotonic used by 90% (837/926) of obstetricians; 79% (726/926) clamp the cord within 20 seconds for term births as do 63% (576/926) for preterm births.Physiological management was used 'always or usually' by 2% (21/926) of obstetricians and 9% (121/1297) of midwives. 81% (747/926) of obstetricians and 89% (1151/1297) of midwives thought more evidence from randomised trials was needed; the most popular question was when is best to clamp the cord. Active management of the third stage of labour is widely used by both obstetricians and midwives in the UK. Syntometrine(R) is usually used for vaginal births and oxytocin for caesarean births; when this is given and when the cord is clamped varies.


[Inhibitory effect of methyl esters of arginine-containing oligopeptides on thrombin and trypsin].
Stereoisomeric oligopeptides were studied for their inhibitory effect on the hydrolysis of benzoyl-L-arginine methyl ester catalyzed by thrombin and trypsin, as well as on the thrombin-fibrinogen reaction. Comparison of the peptide structures, their conformational flexibility and inhibitory effects on thrombin and trypsin shows the availability of the essential differences in organization and functioning of the subsites S3, S2 and S'1 of these enzymes. In contrast to trypsin, thrombin is shown to be characterized by more pronounced secondary stereospecificity. This manifests in the more vigorous dropping of the catalytic constants of thrombin-catalyzed esterolysis than those of trypsin-catalyzed hydrolysis of the substrates, containing D-amino acids at the subsite P2. It is revealed that the peptide Tos-D-Val-D-Ala-D-Agr-D-Phe-OCH3 is the most powerful inhibitor among studied compounds. It is noteworthy that its antithrombin effect is almost an order of magnitude higher than its antitrypsin effect.


The role of multilevel factors in geographic differences in bicycle crash risk: a prospective cohort study.
Regular cycling plays an important role in increasing physical activity levels but raises safety concerns for many people. While cyclists bear a higher risk of injury than most other types of road users, the risk differs geographically. Auckland, New Zealand's largest urban region, has a higher injury risk than the rest of the country. This paper identified underlying factors at individual, neighbourhood and environmental levels and assessed their relative contribution to this risk differential. The Taupo Bicycle Study involved 2590 adult cyclists recruited in 2006 and followed over a median period of 4.6 years through linkage to four national databases. The Auckland participants were compared with others in terms of baseline characteristics, crash outcomes and perceptions about environmental determinants of cycling. Cox regression modelling for repeated events was performed with multivariate adjustments. Of the 2554 participants whose addresses could be mapped, 919 (36%) resided in Auckland. The Auckland participants were less likely to be Māori but more likely to be socioeconomically advantaged and reside in an urban area. They were less likely to cycle for commuting and off-road but more likely to cycle in the dark and in a bunch, use a road bike and use lights in the dark. They had a higher risk of on-road crashes (hazard ratio: 1.47; 95% CI: 1.22, 1.76), of which 53% (95% CI: 20%, 72%) was explained by baseline differences, particularly related to cycling off-road, in the dark and in a bunch and residing in urban areas. They were more concerned about traffic volume, speed and drivers' behaviour. The excess crash risk in Auckland was explained by cycling patterns, urban residence and factors associated with the region's car-dominated transport environment.


Quantitative Comparison of Abundance Structures of Generalized Communities: From B-Cell Receptor Repertoires to Microbiomes.
The community, the assemblage of organisms co-existing in a given space and time, has the potential to become one of the unifying concepts of biology, especially with the advent of high-throughput sequencing experiments that reveal genetic diversity exhaustively. In this spirit we show that a tool from community ecology, the Rank Abundance Distribution (RAD), can be turned by the new MaxRank normalization method into a generic, expressive descriptor for quantitative comparison of communities in many areas of biology. To illustrate the versatility of the method, we analyze RADs from various generalized communities, i.e. assemblages of genetically diverse cells or organisms, including human B cells, gut microbiomes under antibiotic treatment and of different ages and countries of origin, and other human and environmental microbial communities. We show that normalized RADs enable novel quantitative approaches that help to understand structures and dynamics of complex generalized communities.


The evolution of wetness perception: A comparison of arachnid, insect and human models.
Hygroreceptors are a type of humidity sensor that have been identified in several invertebrate classes including Insecta and Arachnida. While their structure has been well researched, the nature of the mechanisms behind their function is debated as being either mechanical, evaporative, or psychrometric in insects and potentially also olfactory in arachnids. There is evidence that can be used to support or oppose each of these concepts, which also invites the possibility of multiple unified mechanisms occurring together. The integration of multiple sensory modalities has also formed the foundation of wetness perception in humans, led by thermal and tactile cues with supplementary information from vision and sound. These inputs are integrated by a vast neural network in the brain, which also occurs on a smaller scale in insects and arachnids. It is possible that as cerebral capacity increased throughout human evolution, this facilitated a preferable system of wetness perception via multisensory integration and rendered hygroreceptors obsolete. While this cerebral development hypothesis is only speculative, it gives a framework for further investigation. Additional research needs to be conducted to correctly classify hygroreceptor types in invertebrates and their relative prevalence before evolutionary associations can be made with vertebrate species. This integratory premise also applies to the human system, as knowing the relative contribution and compounding effects of each sensory modality on wetness perception will aid the overall understanding of the system and help to uncover the evolutionary development pathways underpinning each sense.


Copper tolerance and virulence in bacteria.
Copper (Cu) is an essential trace element for all aerobic organisms. It functions as a cofactor in enzymes that catalyze a wide variety of redox reactions due to its ability to cycle between two oxidation states, Cu(I) and Cu(II). This same redox property of copper has the potential to cause toxicity if copper homeostasis is not maintained. Studies suggest that the toxic properties of copper are harnessed by the innate immune system of the host to kill bacteria. To counter such defenses, bacteria rely on copper tolerance genes for virulence within the host. These discoveries suggest bacterial copper intoxication is a component of host nutritional immunity, thus expanding our knowledge of the roles of copper in biology. This review summarizes our current understanding of copper tolerance in bacteria, and the extent to which these pathways contribute to bacterial virulence within the host.


Heptanuclear antiferromagnetic Fe(III)-D-(-)-quinato assemblies with an S = 3/2 ground state-pH-specific synthetic chemistry, spectroscopic, structural, and magnetic susceptibility studies.
Iron is an essential metal ion with numerous roles in biological systems and advanced abiotic materials. D-(-)-quinic acid is a cellular metal ion chelator, capable of promoting reactions with metal M(II,III) ions under pH-specific conditions. In an effort to comprehend the chemical reactivity of well-defined forms of Fe(III)/Fe(II) toward α-hydroxycarboxylic acids, pH-specific reactions of: (a) [Fe3O(CH3COO)6(H2O)3]·(NO3)·4H2O with D-(-)-quinic acid in a molar ratio 1:3 at pH 2.5 and (b) Mohr's salt with D-(-)-quinic acid in a molar ratio 1:3 at pH 7.5, respectively, led to the isolation of the first two heptanuclear Fe(III)-quinato complexes, [Fe7O3(OH)3(C7H10O6)6]·20.5H2O (1) and (NH4)[Fe7(OH)6(C7H10O6)6]·(SO4)2·18H2O (2). Compounds 1 and 2 were characterized by analytical, spectroscopic (UV-vis, FT-IR, EPR, and Mössbauer) techniques, CV, TGA-DTG, and magnetic susceptibility measurements. The X-ray structures of 1 and 2 reveal heptanuclear assemblies of six Fe(III) ions bound by six doubly deprotonated quinates and one Fe(III) ion bound by oxido- and hydroxido-bridges (1), and hydroxido-bridges (2), all in an octahedral fashion. Mössbauer spectroscopy on 1 and 2 suggests the presence of Fe(III) ions in an all-oxygen environment. EPR measurements indicate that 1 and 2 retain their structure in solution, while magnetic measurements reveal an overall antiferromagnetic behavior with a ground state S = 3/2. The collective physicochemical properties of 1 and 2 suggest that the (a) nature of the ligand, (b) precursor form of iron, (c) pH, and (d) molecular stoichiometry are key factors influencing the chemical reactivity of the binary Fe(II,III)-hydroxycarboxylato systems, their aqueous speciation, and ultimately through variably emerging hydrogen bonding interactions, the assembly of multinuclear Fe(III)-hydroxycarboxylato clusters with distinct lattice architectures of specific dimensionality (2D-3D) and magnetic signature.


Intracellular visualization of prostate cancer using magnetic resonance imaging.
The term "molecular imaging" can be broadly defined as the in vivo characterization and measurement of biological processes at the cellular and molecular level. Is a gene expression magnetic resonance imaging (MRI) possible? Therefore, we have developed a novel intravital and intracellular MRI contrast agent composed of a gadolinium complex, an oligonucleotide sequence [peptide nucleic acid (PNA)], and a transmembrane carrier peptide that is composed of a peptide sequence similar to that of the homeodomain of the Antennapedia protein. The goal of our study was to determine whether this contrast agent could be accumulated in tumor cells in vitro (HeLa cells) and in vivo (Dunning R3327 AT1 rat prostate adenocarcinoma) and whether the specificity of the PNA for the up-regulated c-myc mRNA in the cell's cytoplasm would have an effect on contrast agent retention in the tumor cells. Using the c-myc-specific and a c-myc-nonspecific control PNA, an increase in signal intensity in the tumor cells was observed after 10 min in vitro and in vivo (maximum was reached in HeLa cells in vitro in 60 min, in Dunning R3327 AT1 rat prostate adenocarcinoma cells in vivo in 30 min). This increase of signal intensity could be maintained in vitro in HeLa cells for only 4 h and in Dunning R3327 AT1 rat prostate adenocarcinoma cells in vivo at least for 5 h by using the c-myc mRNA-specific PNA as a "retention" agent.


Salvage extracorporeal membrane oxygenation in induction-associated acute respiratory distress syndrome in acute leukemia patients: A case series.
The prognosis of hematologic malignancies has improved over the past three decades. However, the prognosis in hematologic malignancies with severe acute respiratory distress syndrome has remained poor. Initial reports regarding the utility of extracorporeal membrane oxygenation in hematologic malignancies have been controversial, with limited evaluations of acute leukemia patients supported by extracorporeal membrane oxygenation. We conducted a retrospective review of patients with acute leukemia who developed acute respiratory distress syndrome requiring veno-venous extracorporeal membrane oxygenation support at our facility from July 2015 through August 2017. Four cases of acute myelogenous leukemia with respiratory failure and acute respiratory distress syndrome treated with veno-venous extracorporeal membrane oxygenation while undergoing induction chemotherapy were identified. All patients completed induction therapy with addition of extracorporeal membrane oxygenation support, with two patients dying secondary to their acute leukemia and the other two surviving to allogeneic hematopoietic stem cell transplant. Overall, 75% (three of four) survived to decannulation with a 1-year survival rate following extracorporeal membrane oxygenation of 50% (two of four). Currently, the use of extracorporeal membrane oxygenation in patients with hematologic malignancies who develop severe acute respiratory distress syndrome remains controversial. Although extracorporeal membrane oxygenation in post-allogeneic hematopoietic stem cell transplant is associated with poorer outcomes, our data suggest that salvage extracorporeal membrane oxygenation support is a viable option to manage moderate to severe acute respiratory distress syndrome while completing therapeutic chemotherapy and following in the peri-induction phase of acute leukemia.


Primary osteoarthritis of the elbow: current treatment options.
In the elbow, as in other joints, primary osteoarthritis is characterized by pain, stiffness, mechanical symptoms, and weakness. But primary osteoarthritis of the elbow is unique in that there is relative preservation of articular cartilage and maintenance of joint space, with hypertrophic osteophyte formation and capsular contracture. Medical treatment and physical therapy may be initiated in the early stages of the disease process. Surgical treatment options include arthroscopic osteocapsular débridement, open ulnohumeral arthroplasty, distraction interposition arthroplasty, and total elbow arthroplasty. The potential for instability and loosening following total elbow arthroplasty in the setting of primary osteoarthritis limits the clinical application of this procedure. This patient population is generally younger than that recommended for total elbow arthroplasty, and their higher functional demands have limited the long-term success of this treatment option. The improvement in arthroscopic débridement techniques is perhaps the greatest advancement in the treatment of osteoarthritis of the elbow in recent years.


Development of an effective polarizable bond method for biomolecular simulation.
An effective polarizable bond (EPB) model has been developed for computer simulation of proteins. In this partial polarizable approach, all polar groups of amino acids are treated as polarizable, and the relevant polarizable parameters were determined by fitting to quantum calculated electrostatic properties of these polar groups. Extensive numerical tests on a diverse set of proteins (including 1IEP, 1MWE, 1NLJ, 4COX, 1PGB, 1K4C, 1MHN, 1UBQ, 1IGD) showed that this EPB model is robust in MD simulation and can correctly describe the structure and dynamics of proteins (both soluble and membrane proteins). Comparison of the computed hydrogen bond properties and dynamics of proteins with experimental data and with results obtained from the nonpolarizable force field clearly demonstrated that EPB can produce results in much better agreement with experiment. The averaged deviation of the simulated backbone N-H order parameter of the B3 immunoglobobulin-binding domain of streptococcal protein G from experimental observation is 0.0811 and 0.0332 for Amber99SB and EPB, respectively. This new model inherited the effective character of the classic force field and the fluctuating feature of previous polarizable models. Different from other polarizable models, the polarization cost energy is implicitly included in the present method. As a result, the present method avoids the problem of over polarization and is numerically stable and efficient for dynamics simulation. Finally, compared to the traditional fixed AMBER charge model, the present method only adds about 5% additional computational time and is therefore highly efficient for practical applications.


Dynamics of hospitalizations in hemodialysis patients: results from a large US provider.
In chronic hemodialysis (HD), patients' hospitalizations result in significant costs and affect the quality of life. We aimed at understanding hospitalization rates before death and to identify patterns in clinical and laboratory parameters that precede the first hospitalization. We conducted two separate analyses in patients treated in the 51 US Renal Research Institute HD facilities. The first analysis involved hospitalizations before death in all HD patients who died between 1 January 2007 and 31 December 2011. In the second analysis, we studied the evolution of laboratory and treatment parameters before hospitalization in all patients with, at least, one hospital admission between 1 January 2007 and 31 December 2011. Patients were followed from up to 6 months prior to their first hospital admission. For comparison, we selected non-hospitalized patients and observed the evolution of their laboratory and treatment parameters. We studied 6262 patients in total. The first analysis encompassed 2058 deaths. In these patients, hospitalization increased from 0.32 admissions per patient-month 4 months before death to 1.85 in the month of death. In the second analysis, we studied the first hospitalizations in 4204 patients. Irrespective of the cause of hospitalization, all hospitalizations were preceded by an increase in the neutrophil-to-lymphocyte ratio, a decline in hemoglobin and a reduction in effective treatment time and inter-dialytic weight gain. We noted no comparable trends in non-hospitalized patients. Hospitalization rates increase sharply before death. Months before the first hospitalization changes in clinical and laboratory parameters ensued. These results suggest that models aiming at predicting hospitalization should include indicators capturing the dynamics of relevant parameters.


DNA Methylation in Ensifer Species during Free-Living Growth and during Nitrogen-Fixing Symbiosis with Medicago spp.
Methylation of specific DNA sequences is ubiquitous in bacteria and has known roles in immunity and regulation of cellular processes, such as the cell cycle. Here, we explored DNA methylation in bacteria of the genus Ensifer, including its potential role in regulating terminal differentiation during nitrogen-fixing symbiosis with legumes. Using single-molecule real-time sequencing, six genome-wide methylated motifs were identified across four Ensifer strains, five of which were strain-specific. Only the GANTC motif, recognized by the cell cycle-regulated CcrM methyltransferase, was methylated in all strains. In actively dividing cell cultures, methylation of GANTC motifs increased progressively from the ori to ter regions in each replicon, in agreement with a cell cycle-dependent regulation of CcrM. In contrast, there was near full genome-wide GANTC methylation in the early stage of symbiotic differentiation. This was followed by a moderate decrease in the overall extent of methylation and a progressive decrease in chromosomal GANTC methylation from the ori to ter regions in later stages of differentiation. Based on these observations, we suggest that CcrM activity is dysregulated and constitutive during terminal differentiation, which we hypothesize is a driving factor for endoreduplication of terminally differentiated bacteroids. IMPORTANCE Nitrogen fixation by rhizobia in symbiosis with legumes is economically and ecologically important. The symbiosis can involve a complex bacterial transformation-terminal differentiation-that includes major shifts in the transcriptome and cell cycle. Epigenetic regulation is an important regulatory mechanism in diverse bacteria; however, the roles of DNA methylation in rhizobia and symbiotic nitrogen fixation have been poorly investigated. We show that aside from cell cycle regulation, DNA methyltransferases are unlikely to have conserved roles in the biology of bacteria of the genus Ensifer. However, we present evidence consistent with an interpretation that the cell cycle methyltransferase CcrM is dysregulated during symbiosis, which we hypothesize may be a key factor driving the cell cycle switch in terminal differentiation required for effective symbioses.


Terselenophene Regioisomer Conjugated Polymer Materials for High-Performance Cancer Phototheranostics.
Molecular isomerization is a fundamental issue in the development of functional materials, with a crucial impact on photophysical properties. However, up to now, their effect on photothermal conversion is rarely investigated. Here, two near-infrared (NIR)-absorbing regioisomer conjugated polymers integrated with cis/trans-terselenophenes are designed and synthesized as efficient photothermal agents to enhance cancer phototheranostics. It is demonstrated that enhanced quinoidal resonance of trans-terselenophenes allows the resulting trans-CP to possess more planar backbone to further increase the effective conjugation length and result in the strong absorption spectra at 808 nm. Characterization of photophysical properties has proved that the photothermal conversion efficiency of trans-CP nanoparticles is up to 61.4%, and they are 210% as strong as cis-CP nanoparticles (29.4%). Further in vitro and in vivo works demonstrate efficient photothermal therapeutic effects with the guidance of photoacoustic imaging. This work affords a new understanding of the molecular isomerization into the development of conjugated materials for high-performance cancer phototheranostics.


The Impact of COVID-19 on Neuro-Ophthalmology Office Visits and Adoption of Telemedicine Services.
The COVID-19 public health emergency (PHE) has significantly changed medical practice in the United States, including an increase in the utilization of telemedicine. Here, we characterize change in neuro-ophthalmic care delivery during the early COVID-19 PHE, including a comparison of care delivered via telemedicine and in office. Neuro-ophthalmology outpatient encounters from 3 practices in the United States (4 providers) were studied during the early COVID-19 PHE (March 15, 2020-June 15, 2020) and during the same dates 1 year prior. For unique patient visits, patient demographics, visit types, visit format, and diagnosis were compared between years and between synchronous telehealth and in-office formats for 2020. There were 1,276 encounters for 1,167 patients. There were 30% fewer unique patient visits in 2020 vs 2019 (477 vs 670) and 55% fewer in-office visits (299 vs 670). Compared with 2019, encounters in 2020 were more likely to be established, to occur via telemedicine and to relate to an efferent diagnosis. In 2020, synchronous telehealth visits were more likely to be established compared with in-office encounters. In the practices studied, a lower volume of neuro-ophthalmic care was delivered during the early COVID-19 public health emergency than in the same period in 2019. The type of care shifted toward established patients with efferent diagnoses and the modality of care shifted toward telemedicine.


Accuracy of orthodontic miniscrew implantation guided by stereolithographic surgical stent based on cone-beam CT-derived 3D images.
To develop surgical stents for cone-beam computed tomography (CBCT) 3-dimensional (3D) image-based stent-guided orthodontic miniscrew implantation and to evaluate its accuracy. Ten surgical stents were fabricated with stereolithographic appliances (SLAs) according to 3D CBCT image-based virtual implantation plans. Thirty self-drilling miniscrews were implanted at two to three positions on each side of the maxillary or mandibular posterior arches in three phantoms: 20 guided by 10 surgical stents in two phantoms (stent group) and 10 guided freehand in one phantom (freehand group). Six parameters (mesiodistal and vertical deviations at the corona and apex and mesiodistal and vertical angular deviations) were measured to compare variations between the groups. No root damage was found in the stent group, whereas four of 10 miniscrews contacted with roots in the freehand group. In the stent group, deviations in the mesiodistal and vertical directions were 0.15 ± 0.09 and 0.19 ± 0.19 mm at the corona, respectively, and 0.28 ± 0.23 and 0.33 ± 0.25 mm at the apex, respectively; angular deviations in the mesiodistal and vertical directions were 1.47° ± 0.92° and 2.13° ± 1.48°, respectively. In the freehand group, the corresponding results were 0.48 ± 0.46 mm and 0.94 ± 0.87 mm (corona), 0.81 ± 0.61 mm and 0.78 ± 0.49 mm (apex), and 7.49° ± 6.09° and 6.31° ± 3.82°. Significant differences were found in all six parameters between the two groups (Student's t-test, P < .05). 3D CBCT image-based SLA-fabricated surgical stents can provide a safe and accurate method for miniscrew implantation.


Vitamin B12 for cognition.
An association between neuropsychiatric disorders and vitamin B12 deficiency has been recognized since 1849 when pernicious anaemia was first described. It has been suggested that deficiency of vitamin B12 might contribute to age-associated cognitive impairment. Low serum vitamin B12 concentrations are found in more than 10% of older people. A high prevalence of low serum vitamin B12 levels, and other indicators of vitamin B12 deficiency have been reported among people with Alzheimer's disease. A review is needed of trials assessing effects of vitamin B12 supplementation on cognitive function in later life. To examine the effect of B12 supplementation on cognitive function of demented and elderly healthy people in terms of preventing the onset or progression of cognitive impairment or dementia. The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 12 September 2002 using the terms listed in additional table 1. In addition MEDLINE 1966 to 2002/09 and EMBASE 1980-2002/08 were searched using the same terms and cognit* to pick up studies with healthy volunteers. All randomized double-blind trials in which vitamin B12 at any dose was compared with placebo. Both reviewers applied the selection criteria to assess the quality of the studies. One reviewer collated and analysed the data. For each outcome measure data were sought on every patient randomized. From the two included studies (Seal 2002; Fourniere 1997) of people with dementia and low serum vitamin B12 levels, there was no statistically significant evidence of treatment effect, vitamin B12 supplementation compared with placebo, on cognitive function. Evidence of any efficacy of vitamin B12 in improving the cognitive function of people with dementia and low serum B12 levels is insufficient. The two trials of acceptable methodology (Fourniere 1997; Seal 2002) were restricted to a small number of patients with Alzheimer's disease and other types of cognitive impairment. No trials involving people without dementia or using other definitions of vitamin B12 deficiency were found.


Evidence for pore-forming ability by Legionella pneumophila.
Legionella pneumophila is the cause of Legionnaires' pneumonia. After Internalization by macrophages, it bypasses the normal endocytic pathway and occupies a replicative phagosome bound by endoplasmic reticulum. Here, we show that lysis of macrophages and red blood cells by L. pneumophila was dependent on dotA and other loci known to be required for proper targeting of the phagosome and replication within the host cell. Cytotoxicity occurred rapidly during a high-multiplicity infection, required close association of the bacteria with the eukaryotic cell and was a form of necrotic cell death accompanied by osmotic lysis. The differential cytoprotective ability of high-molecular-weight polyethylene glycols suggested that osmotic lysis resulted from insertion of a pore less than 3 nm in diameter into the plasma membrane. Results concerning the uptake of membrane-impermeant fluorescent compounds of various sizes are consistent with the osmoprotection analysis. Therefore, kinetic and genetic evidence suggested that the apparent ability of L. pneumophila to insert a pore into eukaryotic membranes on initial contact may play a role in altering endocytic trafficking events within the host cell and in the establishment of a replicative vacuole.


NSAID-induced bronchospasm--a common and serious problem. A report from MEDSAFE, the New Zealand Medicines and Medical Devices Safety Authority.
Between 8-20 percent of adult asthmatics experience bronchospasm following ingestion of aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs). Termed aspirin-induced asthma, this reaction is potentially fatal. Asthmatics with chronic rhinitis or a history of nasal polyps are at greater risk. The reaction rarely occurs in children. Patients initially present with an acute episode of vague malaise, sneezing, nasal obstruction, rhinorrhoea, and often a productive cough. Persistent rhinitis and nasal polyps may then develop. Asthma and aspirin sensitivity may appear in the following months. Within 20 minutes to 3 hours of taking a NSAID, aspirin-sensitive asthmatics can develop symptoms such as bronchospasm, rhinorrhoea, dyspnoea, cough, or urticaria-angiodema. NSAIDs (systemic or topical) should be used with caution in asthmatics and avoided in asthmatics with nasal polyps. Asthmatics should be told to seek medical help if symptoms worsen on initiation of a NSAID.


CRISPR-based herd immunity can limit phage epidemics in bacterial populations.
Herd immunity, a process in which resistant individuals limit the spread of a pathogen among susceptible hosts has been extensively studied in eukaryotes. Even though bacteria have evolved multiple immune systems against their phage pathogens, herd immunity in bacteria remains unexplored. Here we experimentally demonstrate that herd immunity arises during phage epidemics in structured and unstructured Escherichia coli populations consisting of differing frequencies of susceptible and resistant cells harboring CRISPR immunity. In addition, we develop a mathematical model that quantifies how herd immunity is affected by spatial population structure, bacterial growth rate, and phage replication rate. Using our model we infer a general epidemiological rule describing the relative speed of an epidemic in partially resistant spatially structured populations. Our experimental and theoretical findings indicate that herd immunity may be important in bacterial communities, allowing for stable coexistence of bacteria and their phages and the maintenance of polymorphism in bacterial immunity.


Formation of 7-hydroxymethyl-12-methylbenz(a)anthracene-DNA adducts from 7,12-dimethylbenz(a)anthracene in mouse epidermis.
The formation of DNA adducts from [3H]-7-hydroxymethyl-12-methylbenz(a)anthracene (7-OHM-12-MBA) and [3H]-7,12-dimethylbenz(a)anthracene (DMBA) in the epidermis of Sencar mice was analyzed. Comparison of Sephadex LH-20 chromatographic profiles of DNA samples isolated from mice treated with DMBA or 7-OHM-12-MBA suggested that the DMBA-treated animals contained DNA adduct(s) derived from the further metabolism of 7-OHM-12-MBA. Further analysis of DNA samples from DMBA-treated mice by high-pressure liquid chromatography demonstrated the presence of 5 DNA adducts which were chromatographically indistinguishable from the DNA adducts formed in 7-OHM-12-MBA-treated mice. Epidermal homogenates were utilized to catalyze the covalent binding of [3H]DMBA and [3H]-7-OHM-12-MBA to calf thymus DNA in vitro. Under conditions of limiting concentrations of [3H]DMBA, the majority of the DNA adducts formed chromatographed in regions where 7-OHM-12-MBA-DNA adducts eluted. A major DMBA-DNA adduct formed in this in vitro system eluted with the same retention time as did the major 7-OHM-12-MBA-DNA adduct formed in mouse skin in vivo. These results when coupled with the in vivo data suggest that 7-OHM-12-MBA is an intermediate for at least some of the binding of DMBA to epidermal DNA in Sencar mice.


Cell therapy for central nervous system disorders: Current obstacles to progress.
Cell therapy for disorders of the central nervous system has progressed to a new level of clinical application. Various clinical studies are underway for Parkinson's disease, stroke, traumatic brain injury, and various other neurological diseases. Recent biotechnological developments in cell therapy have taken advantage of the technology of induced pluripotent stem (iPS) cells. The advent of iPS cells has provided a robust stem cell donor source for neurorestoration via transplantation. Additionally, iPS cells have served as a platform for the discovery of therapeutics drugs, allowing breakthroughs in our understanding of the pathology and treatment of neurological diseases. Despite these recent advances in iPS, adult tissue-derived mesenchymal stem cells remain the widely used donor for cell transplantation. Mesenchymal stem cells are easily isolated and amplified toward the cells' unique trophic factor-secretion property. In this review article, the milestone achievements of cell therapy for central nervous system disorders, with equal consideration on the present translational obstacles for clinic application, are described.


Preparation of B4Cp/Al Composites via Selective Laser Melting and Their Tribological Properties.
B4C-particle-reinforced Al (B4Cp/Al) composites are widely used in various areas, e.g., armors, electronic packaging and fuel storage, owing to their several outstanding properties including high specific rigidity, excellent wear resistance and light weight. Selective laser melting (SLM) is favored in manufacturing complex components because of its high raw material utilization rate and high efficiency. In this work, a B4Cp/Al composite was successfully synthesized by SLM, and the effects of one of the most important parameters, scanning speed (100-700 mm/s), on the phase composition, density, microhardness and tribological properties of the samples were investigated. The microhardness, relative density and dry-sliding wear resistance of as-prepared B4Cp/Al composites were improved with the decrease in scanning speed, and the sample fabricated at a scanning speed of 100 mm/s exhibited a relative density as high as about 97.1%, and a maximum microhardness of ~180 HV0.1 (approximately six times more than that of the SLM-formed pure Al sample, 31 HV0.1), a minimum wear rate of 4.2 × 10-5 mm3·N-1·m-1 and a corresponding friction coefficient of 0.41. In addition, abrasive wear, adhesive wear and oxidation wear were found to be behind the overall wear behavior of as-prepared B4Cp/Al composites.


Improvement of the oxidation stability of cobalt nanoparticles.
In order to enhance the resistance of cobalt nanoparticles to oxidation in air, the impact of different stabilization strategies on the isothermal oxidation of particle dispersions and powders was kinetically investigated and compared to as-prepared particle preparations. A post-synthesis treatment with different alcohols was employed, and we also investigate the influence of two different polymer shells on the oxidation process. We found a parabolic decrease of the magnetization for all particle charges, indicating that the process is dominated by a diffusion of oxygen to the cobalt core and a radial growth of the oxide layer from the particle surface to the core. A significant deceleration of the oxidation process was observed for all alcohol-passivated particle preparations, and this resulted finally in a stagnation effect. The stabilizing effect increases in the sequence Co@OA/MeOH < Co@OA/EtOH < Co@OA/iPrOH. For polymer-coated particle preparations Co@PCL and Co@PS, the deceleration was even more pronounced. The results demonstrate that cobalt nanoparticles can effectively be protected against oxidation in order to improve their mid- to longterm stability.


Phosphatidic acid phosphohydrolase 1 and 2 regulate phospholipid synthesis at the endoplasmic reticulum in Arabidopsis.
Phospholipid biosynthesis is essential for the construction of most eukaryotic cell membranes, but how this process is regulated in plants remains poorly understood. Here, we show that in Arabidopsis thaliana, two Mg(2+)-dependent phosphatidic acid phosphohydrolases called PAH1 and PAH2 act redundantly to repress phospholipid biosynthesis at the endoplasmic reticulum (ER). Leaves from pah1 pah2 double mutants contain ~1.8-fold more phospholipid than the wild type and exhibit gross changes in ER morphology, which are consistent with massive membrane overexpansion. The net rate of incorporation of [methyl-(14)C]choline into phosphatidylcholine (PC) is ~1.8-fold greater in the double mutant, and the transcript abundance of several key genes that encode enzymes involved in phospholipid synthesis is increased. In particular, we show that PHOSPHORYLETHANOLAMINE N-METHYLTRANSFERASE1 (PEAMT1) is upregulated at the level of transcription in pah1 pah2 leaves. PEAMT catalyzes the first committed step of choline synthesis in Arabidopsis and defines a variant pathway for PC synthesis not found in yeasts or mammals. Our data suggest that PAH1/2 play a regulatory role in phospholipid synthesis that is analogous to that described in Saccharomyces cerevisiae. However, the target enzymes differ, and key components of the signal transduction pathway do not appear to be conserved.


Direct effect of beta-adrenergic stimulation on renin release by the rat kidney slice in vitro.
Controversy exists regarding the mechanism by which catecholamines stimulate renin secretion in vivo. A sensitive rat kidney slice system was utilized to study the direct effects of adrenergic agonists and antagonists on renin release in vitro. Catecholamines were protected from degradation by the addition of ascorbic acid to the incubation medium. Significant dose-related stimulation of renin release was observed with epinephrine and norepinephrine in concentrations from 1.5 times 10(-9) to 1.5 times 10(-7)M and with isoproterenol in concentrations from 2 times 10(-9) to 2 times 10(-7)M. No significant stimulation was seen with 10(-10)M concentrations of the three agents. Methoxamine (10(-6)M) stimulated renin release significantly (P less than 0.01). The stimulation observed with epinephrine, norepinephrine, or isoproterenol was blocked by d,l- and l-propranolol (2 times 10(-4)M) but not by d-ropranolol (2 times 10(-4)M) or phentolamine (9 times 10(-4)M). Methoxamine-induced stimulation was abolished by d,l-propranolol but not by phentolamine. These data that the in vitro kidney slice system is responsive to physiological concentrations of catecholamines when they are protected from degradation. The results further demonstrate a direct stimulatory role for beta-adrenergic agents on renin release and suggest that alpha-adrenergic effects seen in vivo are mediated indirectly by hemodynamic, vascular, or functional changes in the kidney.


Plastic Additives in Ambient Fine Particulate Matter in the Pearl River Delta, China: High-Throughput Characterization and Health Implications.
Elucidation of the chemical components of airborne fine particulate matter (PM2.5) facilitates the characterization of atmospheric contamination sources and associated human exposure risks. In the present study, we employed a high-throughput analytical approach to investigate the abundance and distribution of 163 plastic additives in ambient PM2.5 collected from 94 different sites across the Pearl River Delta region, China. These chemicals are from six categories, including organophosphate esters (OPEs), phthalate esters (PAEs), PAE replacements, bisphenol analogues, UV stabilizers, and antioxidants. Ninety-three of them exhibited a detection frequency greater than 50% in PM2.5, while the combined concentrations of target plastic additives ranged from 610 to 49,400 μg/g (median: 3500 μg/g) across sites. By category, concentrations of PAEs (median: 2710 μg/g) were one to three orders of magnitude greater than those of other groups, followed by PAE replacements (540 μg/g) and OPEs (76.2 μg/g). Chemical-dependent exposure risks to PM2.5-bound plastic additives were characterized via the estimated daily intake and hazard quotient (HQ) approaches, which resulted in two different risk prioritization systems. Although the HQ approach suggested no or very low health concerns when considering individual chemicals, the complexity of co-concurrent chemicals in PM2.5 raises the concern on potential health risks from exposure to airborne particles and a cocktail of chemical components.


Prevalence of adenomas and advanced adenomas in patients in the 40- to 49-year age group undergoing screening colonoscopy because of a family history of adenoma/polyp in a first-degree relative.
Per current guidelines, patients with a first-degree relative (FDR) with adenomas should get screened at age 40. Data on the prevalence of adenomas and advanced adenomas (AAs) in these patients are lacking. To examine the prevalence of adenomas and AAs in 40- to 49-year-old individuals undergoing screening colonoscopy because of a family history (FH) of polyps and to compare these data with those of a control population of similar age. Retrospective cross-sectional study. Tertiary care academic medical center and Veterans Affairs medical center. Study subjects included all 40- to 49-year-old asymptomatic individuals undergoing initial screening colonoscopy at our institution from January 1, 2006, to June 1, 2009, because of an FDR with polyps. The control population consisted of all 40- to 49-year-old individuals who underwent their first colonoscopy during the same period because of abdominal pain, diarrhea, or constipation without an FH of polyps or colorectal cancer. Colonoscopy. The prevalence of adenomas of any size, AAs, and risk factors associated with adenomas. The prevalence of adenomas was greater in the FH of polyps group (n = 176) compared with the control sample (n = 178) (26.7% vs 13.5%; P = .002) but was not statistically greater for AAs (5.7% vs 3.4%; P = .3). After adjusting for confounders, FH of a polyp was associated with an increased prevalence of adenomas (odds ratio 2.8 [95% CI, 1.4-5.5]). Limited data on polyp histology in FDRs and limited sample size. Among 40- to 49-year-old patients undergoing screening colonoscopy because of an FDR with polyps, the prevalence of adenomas was greater than in a control population. Prospective research is needed to quantify the prevalence of AAs in this group and to determine whether these individuals should undergo screening colonoscopy at age 40.


Efficient replication of human immunodeficiency virus type 1 requires a threshold level of Rev: potential implications for latency.
The Rev protein of human immunodeficiency virus type 1 (HIV-1) is essential for the expression of the structural genes of HIV-1. To determine whether a functional threshold level of Rev is required to allow efficient HIV-1 replication, CD4-positive HeLa cells, constitutively expressing a Rev-deficient provirus, were transfected with various quantities of a Rev-expressing plasmid. Compared with the quantity of the Rev-producing plasmid transfected, HIV-1 replication was distinctly nonlinear as measured by HIV-1 p24 antigen and HIV-1-specific RNA production. A quantitative RNA polymerase chain reaction (PCR) demonstrated that Rev mRNA expression was linearly correlated with the quantity of Rev-expressing plasmid which was transfected into these cells. These data suggest that a critical threshold of Rev is required for a highly productive HIV-1 infection. This threshold level of Rev may be involved in the generation and maintenance of HIV-1 proviral latency.


West Nile virus outbreak in humans in Croatia, 2012.
During August and September 2012, seven cases of West Nile neuroinvasive disease were identified in three north-eastern counties of Croatia. Four cases were reported in Osijek-Baranja County, two in Brod-Posavina County and one in Vukovar-Srijem County. The median age of the patients was 62.7 years. All patients were hospitalized for 2-5 weeks. The patients from Slavonski Brod had more severe clinical presentation of disease with prolonged hospitalization. Medical entomological research was carried out in 64 localities, where 1785 mosquitoes were captured. Among the analyzed mosquitoes, 114 were determined to be Culex pipiens and subjected to molecular characterization for the presence of virus. No viral RNA was detected in mosquitoes. Subsequent public health measures taken include mosquito control in all settlements where disease was detected.


[Excimer laser keratomileusis for myopia correction. Results and complications].
Results of excimer laser keratomileusis in 26 myopic sighted eyes are presented. The follow-up was at least 9 months. The base-line refraction was -4.48 +/- 1.81 D (range: -1.4 to -9.25 D). After 3 months 85% were within +/- 1 D from the intended refraction. The such defined success rate after 6 months was 87.5%, after 9 months 88%, and after 12 months 92%. One month after surgery we found an overcorrection of +1.45 +/- 1.22 D decreasing to +0.27 +/- 0.94 D at three months, becoming an undercorrection of -0.24 +/- 0.76 D after six, and -0.32 +/- 0.69 D after nine months, and of -0.36 +/- 0.6 D after one year. Stability within the measurement error (+/- 0.25 D) appeared in 79% of the treated eyes six months after treatment. Three patients have been excluded from the study group because they did not follow the protocol. Subepithelial haze occurred in all patients, becoming most intense after 3 months, gradually clearing over the next months. With appropriate steroid medication, the refractive effect may be modulated. Complications as steroid glaucoma, recurrent erosion, loss of acuity, or extensive corneal scarring seem to be very rare.


Defining and searching for structural motifs using DeepView/Swiss-PdbViewer.
Today, recognition and classification of sequence motifs and protein folds is a mature field, thanks to the availability of numerous comprehensive and easy to use software packages and web-based services. Recognition of structural motifs, by comparison, is less well developed and much less frequently used, possibly due to a lack of easily accessible and easy to use software. In this paper, we describe an extension of DeepView/Swiss-PdbViewer through which structural motifs may be defined and searched for in large protein structure databases, and we show that common structural motifs involved in stabilizing protein folds are present in evolutionarily and structurally unrelated proteins, also in deeply buried locations which are not obviously related to protein function. The possibility to define custom motifs and search for their occurrence in other proteins permits the identification of recurrent arrangements of residues that could have structural implications. The possibility to do so without having to maintain a complex software/hardware installation on site brings this technology to experts and non-experts alike.


Total axillary lymphadenectomy in the management of breast cancer.
The optimal extent of axillary dissection in patients with breast cancer remains unclear. We report 278 total axillary lymphadenectomies (levels I, II, and III and Rotter's [interpectoral] nodes) that were performed in 264 closely followed up private patients. There have been no axillary recurrences to date (mean follow-up, 50 months). If only level I and II nodes had been removed, the false-negative staging error would have been only 2.6%. However, 29 (31.5%) of 92 pathological node-positive axillae contained apical and/or Rotter's metastases. The incidence of complications was comparable with that reported for partial lymphadenectomy. Arm lymphedema developed in 6% of nonirradiated patients; postoperative radiotherapy and gross nodal disease were significant risk factors for lymphedema. Total axillary lymphadenectomy largely prevents axillary, recurrence, eliminates the small staging error inherent in partial lymphadenectomy, and has acceptable morbidity, provided radiotherapy to the regional nodal areas is avoided.


[Effect of a constant and low frequency magnetic field on the behavioral and autonomic responses of the human operator].
The object of the study was conjugation of latencies of sensorimotor reactions and of following physiological characteristics: respiratory rate, heart rate, skin resistance and temperature, in man doing the work of operator, under the action of DC and AC (50 c/s) magnetic fields with maximal tension equalling 8-10 a/m on the head. "Disfunction" of behavioural reactions and of their vegetative sufficiency was observed in the magnetic field. The degree of deterioration of control and compensatory properties of the central nervous system is of inverse dependence on the quality of the operator's work and the level of the central nervous system functional possibilities.


Functional effects of amino acid substitutions at residue 33 of human thymidylate synthase.
Fluorinated pyrimidines, such as 5-fluorouracil (FUra) and 5-fluoro-2'-deoxyuridine (FdUrd), are cytotoxic to cells as a consequence of generation of 5-fluoro-2'-deoxyuridylate (FdUMP), which is a mechanism-based inhibitor of the enzyme thymidylate synthase (TS). FdUMP inhibits TS via its binding into a stable inhibitory ternary complex (ITC) with the enzyme and the cosubstrate N5, N10-methylene-5,6,7,8-tetrahydrofolate (CH2H4PteGlu). In previous studies, we identified a naturally occurring mutant form of human TS that contains a Tyr-->His substitution at residue 33 and confers relative resistance to FdUrd in both mammalian and bacterial cells. Kinetic studies indicated that the equilibrium dissociation constant (Kd) for binding of FdUMP into the ITC is altered in the mutant enzyme. In the current investigation, we have examined the kinetics of FdUMP binding into covalent binary complexes, i.e., in the absence of CH2H4PteGlu. Our results showed that although the rate constants for binary FdUMP binding (i.e., kon and koff) are altered by the Tyr-->His substitution, there is no measurable effect on the overall Kd. Analysis of a number of other amino acid substitutions at residue 33 indicated that maximal enzyme accumulation and function requires a bulky, hydrophobic side chain at this site.


Mechanism of antimicrobial action of indolicidin.
Indolicidin, a 13-residue antimicrobial peptide isolated from cytoplasmic granules of bovine neutrophils, exhibits activity against Gram-positive and Gram-negative bacteria as well as fungi. Although indolicidin is bactericidal and permeabilizes the bacterial membranes, it does not lyse the bacterial cells. We examined the effect of bactericidal concentrations of indolicidin on the morphology of Escherichia coli cells and found that it induces filamentation. Further investigations showed that indolicidin inhibits DNA synthesis in E. coli cells at concentrations at which RNA and protein synthesis are either partially affected or not affected at all. Since inhibition of DNA synthesis is also known to induce filamentation in E. coli, it appears to contribute to the antimicrobial activity of indolicidin.


Effect of M1 protein and low pH on nuclear transport of influenza virus ribonucleoproteins.
Influenza virus enters its host cell by receptor-mediated endocytosis followed by acid-activated membrane fusion in endosomes. The viral ribonucleoprotein particles (vRNPs) delivered into the cytosol then dissociate from the matrix protein, M1, and from each other, after which they are individually imported into the nucleus via the nuclear pores. For some time, it has been believed that the low pH in endosomes may, in some way, trigger the capsid disassembly events necessary for nuclear transport. This report provides direct evidence that the association of M1 with vRNPs is sensitive to mildly acidic pH within the infected cell. Recombinant M1, expressed in cultured cells, was found to associate with vRNPs and inhibit their nuclear import. Brief acidification of the cytosolic compartment eliminated the interfering activity and allowed the incoming vRNPs to enter the nucleus. Newly assembled progeny M1-vRNP complexes in the cytosol of infected cells were also dissociated by brief acidification. Acidic pH was thus found to serve as a switch that allowed M1 to carry out its multiple functions in the uncoating, nuclear transport, and assembly of vRNPs.


Identification of valve-related artifact during cardiac mapping.
During cardiac mapping, it is critical to discriminate signals related to cardiac conduction versus those due to mechanical interaction with other cardiac structures such as valves. We sought to define characteristics that could facilitate discrimination of valve artifact from cardiac conduction signals. Patients with structurally normal heart undergoing mapping for ventricular arrhythmias arising from the vicinity of the aortic valve between January 2013 and May 2015 were included. Potentials felt to reflect aortic valve opening (occurring at the end of the QRS after the local ventricular signal) were termed A1, and those felt to reflect valve closure were termed A2. A total of 24 patients had mapping in the sinuses of Valsalva, and 10 (average age 40 + 15, 60% male) were found to have additional signals (A1 and/or A2) notable during mapping. In all patients, intervals between A1 and A2 shortened after ectopic beats and lengthened after compensatory pauses. These variations in the interval matched the change in systolic duration on Doppler echocardiography. Overdrive atrial pacing was performed in four patients, which demonstrated progressive shortening of intervals between A1 and A2. Pacing always revealed local capture without affecting A1 or A2. In the one patient in whom ablation was performed in these areas, there was no effect on A1 or A2, suggesting these signals represented artifact. Valve-related signals in the aortic sinuses are commonly seen and can be distinguished. The interval between A1 and A2 correlated with mechanical systole and varied in a physiologically predictable manner with heart rate changes.


Model based variable selection as a tool to highlight biological differences in Raman spectra of cells.
In vitro Raman spectroscopy used for non-invasive, non-destructive characterization of single cells and tissues has proven to be a powerful tool for understanding the complex biochemical processes within these biological systems. Additionally it enables the comparison of a wide range of in vitro model systems by discriminating them based on their biomolecular differences. However, one persistent challenge in Raman spectroscopy has been the highly complex structure of cell and tissue spectra, which comprise signals from lipids, proteins, carbohydrates and nucleic acids, which may overlap significantly. This leads to difficulty in discerning which molecular components are responsible for the changes seen between experimental groups. To address this problem, we introduce a technique to highlight the significant biochemical changes between sample groups by applying a novel approach using Partial Least Squares - Discriminant Analysis (PLS-DA) Variable Importance Projection (VIP) scores normally used for variable selection as heat maps combined with group difference spectra to highlight significant differences in Raman band shapes and position. To illustrate this method we analyzed single HeLa cells in their live, fixed, fixed and ethanol dehydrated, to the fixed, dehydrated and then rehydrated states respectively. Fixation, ethanol dehydration and rehydration are known to induce molecular changes in the lipids and proteins within each cell.


Leveraging the lessons learned from financing HIV programs to advance the universal health coverage (UHC) agenda in the East African Community.
Although there is broad consensus around the need to accelerate progress towards universal health coverage (UHC) in Sub-Saharan Africa, the financing strategies for achieving it are still unclear. We sought to leverage the lessons learned in financing HIV programs over the past two decades to inform efforts to advance the universal health coverage agenda in the East African Community. We conducted a literature review of studies reporting financing mechanisms for HIV programs between 2004 and 2014. This review is further underpinned by evidence from a mixed-methods study entailing a survey of 195 health facilities across Uganda supplemented with 18 semi-structured interviews with HIV service managers. Our data shows that there are six broad HIV financing strategies with potential for application to the universal health coverage agenda in the East African Community (EAC); i) Bi-lateral and multi-lateral funding vehicles: The establishment of HIV-specific global financing vehicles such as PEPFAR and The Global Fund heralded an era of unprecedented levels of international funding of up to $ 500 billion over the past two decades ii) Eliciting private sector contribution to HIV funding: The private sector's financial contribution to HIV services was leveraged through innovative engagement and collaborative interventions iii) Private sector-led alternative HIV financing mechanisms: The introduction of 'VIP' HIV clinics, special 'HIV insurance' schemes and the rise of private philanthropic aid were important alternatives to the traditional sources of funding iv) Commodity social marketing: Commodity social marketing campaigns led to an increase in condom use among low-income earners v) The use of vouchers: Issuing of HIV-test vouchers to the poor was an important demand-side financing approach vi) Earmark HIV taxes: Several countries in Africa have introduced 'special HIV' taxes to boost domestic HIV funding. The lessons learned from financing HIV programs suggest that a hybrid of funding strategies are advisable in the quest to achieve UHC in EAC partner states. The contribution of the private sector is indispensable and can be enhanced through targeted interventions towards UHC goals.


Characterization of a novel inositol 1,4,5-trisphosphate receptor in isolated olfactory cilia.
Inositol 1,4,5-trisphosphate (InsP3), a product of G-protein-mediated receptor activation of phosphoinositide turnover, plays the role of a second messenger when olfactory neurons are stimulated with certain olfactory stimuli. In this paper we examine the specific binding of [3H]InsP3 to isolated olfactory cilia, microsomes and brain membranes from the channel catfish (Ictalurus punctatus) and, by photoaffinity labelling with an InsP3 analogue (125I-labelled 1-[3-(4-azidosalicyloxy)-aminopropyl]inositol 1,4,5-trisphosphate (125I-ASA-InsP3)], we tentatively identify the major InsP3-binding protein in catfish olfactory cilia. InsP3 binding to ciliary membranes is specific and saturable, with a Kd of 1.10 +/- 0.31 microM and a maximum number of binding sites (Bmax) of 17.6 +/- 5.8 pmol/mg. The rank order for potency of inhibition of [3H]InsP3 binding is Ins(1,4)P2 less than Ins(1,3,4)P3 less than Ins(1,3,4,5)P4 = Ins(1,4,5)P3 less than Ins(2,4,5)P3. Exposure of cilia membranes to u.v. light in the presence of 125I-ASA-InsP3 results in the labelling of a protein with apparent Mr 107,000. Labelling is specifically prevented by Ins(1,4,5)P3, Ins(2,4,5)P3 and Ins(1,3,4,5)P4, but not by Ins(1,4)P2 or Ins(1,3,4)P3. Both specific [3H]InsP3 binding and photoaffinity labelling of the Mr-107,000 protein were displaced by heparin. The Kd and the inhibition of [3H]InsP3 binding and of photoaffinity labelling by inositol phosphates and heparin are consistent with the ability of micromolar concentrations of Ins(1,4,5)P3 [but not Ins(1,3,4)P3] to activate the InsP3-gated currents in patch-clamp experiments with olfactory neurons. These results suggest that InsP3 binding to a Mr-107,000 cilia membrane protein may represent binding to the olfactory InsP3-gated cation channel.


Accuracy of methods for calculating cerebral blood flow from intracarotid xenon-133 injection.
The accuracy of the three commonly used methods, the initial slope analysis, the stochastic analysis, and the compartmental analysis, for calculating mean cerebral blood flow from xenon-133 clearance curves was studied with the use of computer-generated and real curves. The accuracy of calculation was affected by the cutoff time of the curve, by the level of the compartmental blood flows to white and gray matter and by the ratio of these flow levels, by the relative weight of gray matter, and by the choice of the method of calculation. None of the methods was clearly superior to the others. Each had its own defects that render it more or less suitable for different situations. All three methods generally overestimated mean cerebral blood flow. This overestimation was greater the lower the flow. A curve-fitting index was devised which can be used to check the validity of the bicompartmental model when using compartmental analysis. This same index can provide, though not always, an estimate of the error in the calculation of mean cerebral blood flow when an optimization method is used.


Tobacco NtLTP1, a glandular-specific lipid transfer protein, is required for lipid secretion from glandular trichomes.
Glandular trichomes are the phytochemical factories of plants, and they secrete a wide range of commercially important natural products such as lipids, terpenes and flavonoids. Herein, we report that the Nicotiana tabacum LTP1 (NtLTP1) gene, which is specifically expressed in long glandular trichomes, plays a role in lipid secretion from trichome heads. NtLTP1 mRNA is abundantly transcribed in trichomes, but NtLTP3, NtLTP4 and NtLTP5 are not. In situ hybridization revealed that NtLTP1 mRNAs accumulate specifically in long trichomes and not in short trichomes or epidermal cells. X-gluc staining of leaves from a transgenic plant expressing the NtLTP1 promoter fused to a GUS gene revealed that NtLTP1 protein accumulated preferentially on the tops of long glandular trichomes. GFP fluorescence from transgenic tobacco plants expressing an NtLTP1-GFP fusion protein was localized at the periphery of cells and in the excreted liquid droplets from the glandular trichome heads. In vitro assays using a fluorescent 2-p-toluidinonaphthalene-6-sulfonate probe indicated that recombinant NtLTP1 had lipid-binding activity. The overexpression of NtLTP1 in transgenic tobacco plants resulted in the increased secretion of trichome exudates, including epicuticular wax. In transgenic NtLTP1-RNAi lines, liquid secretion from trichomes was strongly reduced, but epicuticular wax secretion was not altered. Moreover, transgenic tobacco plants overexpressing NtLTP1 showed increased protection against aphids. Taken together, these data suggest that NtLTP1 is abundantly expressed in long glandular trichomes, and may play a role in lipid secretion from long glandular trichomes.