Goldilocks Mastectomy: A Safe Bridge to Implant-Based Breast Reconstruction in the Morbidly Obese.
Reconstructive surgeons are encountering an increasing number of obese women requiring postmastectomy reconstruction. These patients are poor candidates for autologous and prosthetic-based reconstructions as they have a high rate of reconstructive failure, surgical complications, and poor aesthetic outcomes. We demonstrate here the utility of the previously described Goldilocks mastectomy with free nipple grafts as a safe bridge to second stage implant-based breast reconstruction. Ten consecutive morbidly (BMI > 40) or super obese (BMI>50) women underwent bilateral Goldilocks mastectomy with free nipple grafts followed by second stage subpectoral implant placement at least three months postoperatively. Patients were assessed for implant-related complications including malposition, capsular contracture, dehiscence, and extrusion. Ten postmastectomy reconstructions in patients with BMIs ranging from 37 to 50 with a mean BMI of 45 underwent bilateral Goldilocks mastectomy with free nipple grafts. Two patients had wound healing complications after Goldilocks mastectomy but were completely healed within 8 weeks. There were no instances of delayed wound healing or reconstructive failure after prosthetic placement. With at least 9 months of follow-up on all patients, no patient has had a capsular contracture, significant malposition, or other complication requiring reoperation. The obese patient poses a significant reconstructive challenge for which no reproducible approach has been described. Here, we present a 2-stage strategy: the previously described Goldilocks mastectomy with free nipple grafts followed by second stage subpectoral definitive implant placement. This is the first proposed description of a reliable strategy for postmastectomy reconstruction in the morbidly and super obese.


Classification of inhibitory amino acid receptors in the mammalian nervous system.
Electrophysiological and pharmacological evidence is summarized for the existence of an inhibitory receptor system operated by glycine and another two separate systems operated by gamma-aminobutyric acid (GABA) through GABA-A and GABA-B receptors, respectively. Claims for subclasses of GABA-A receptor are critically reviewed and found not-proven. A quantitative pharmacological profile of the GABA-A receptor and associated regulatory sites for picrotoxin, barbiturates and benzodiazepines on the dorsal funiculus of the rat cuneate nucleus is described. When compared with this profile and the pharmacological properties of the glycine receptor complex, the effects of taurine cannot be entirely explained by actions on these two receptor systems.


Orthogonal polarization dual-channel holographic memory in cationic ring-opening photopolymer.
A dual-channel holographic recording technique and its corresponding memory scheme in the cationic ring-opening photopolymer are presented. In the dual-channel technique, a pair of holograms are recorded simultaneously with two orthogonal polarization channels in the common volume of the material, and are reconstructed concurrently with negligible inter-channel crosstalk. The grating strengths of these two channels are investigated and the relevant parameters for equal diffraction intensity readout are optimized. Combining the dual-channel technique with speckle shift multiplexing, a high-density holographic memory is realized. This dual-channel scheme enables the users to interact with the storage medium from an additional channel. The simultaneous nature of the two channels also offers a faster data transfer rate in both the recording and reading processes.


Source verification of mis-identified Arabidopsis thaliana accessions.
A major strength of Arabidopsis thaliana as a model lies in the availability of a large number of naturally occurring inbred lines. Recent studies of A. thaliana population structure, using thousands of accessions from stock center and natural collections, have revealed a robust pattern of isolation by distance at several spatial scales, such that genetically identical individuals are generally found close to each other. However, some individual accessions deviate from this pattern. While some of these may be the products of rare long-distance dispersal events, many deviations may be the result of mis-identification, in the sense that the data regarding location of origin data are incorrect. Here, we aim to identify such discrepancies. Of the 5965 accessions examined, we conclude that 286 deserve special attention as being potentially mis-identified. We describe these suspicious accessions and their possible origins, and advise caution with regard to their use in experiments in which accurate information on geographic origin is important. Finally, we discuss possibilities for maintaining the integrity of stock lines.


The structure and enforcement of health insurance rating reforms.
Requiring health insurers to cover everyone who applies regardless of health status--an approach called "guaranteed issue"--is severely hampered without accompanying rating restrictions that keep insurance affordable for higher-risk people. The degree of rating flexibility also determines how much insurers can continue to compete based on their skills at risk selection, and how well they can counter adverse selection. Therefore, the structure and enforcement of rating reforms are essential to how insurance market reforms function. Based on an in-depth qualitative study in seven states with insurers, agents, and regulators, this article explains the factors that determine the stringency of rating reforms, and details how various aspects of rating restrictions can be used strategically to engage in greater risk segmentation than first appears possible. The article concludes by reflecting on the appropriate degree of complexity in rating rules, and it offers recommendations for crafting rating reforms that avoid unintended consequences.


Sleep disturbance and impulsive-compulsive behaviours in Parkinson's disease.
Impulsive-compulsive behaviours (ICBs) in Parkinson's disease (PD) have been anecdotally linked with impaired sleep. The authors investigate measures of sleep in PD patients with and without ICBs, and in healthy controls. The authors compare Parkinsonian features, measures of depression, anxiety and mania, and sleep disturbance in 30 PD patients with ICBs (PD+ICB), 62 PD patients without ICBs (PD-ICB) and 48 healthy controls. PD+ICB patients had a younger age of PD onset, took more dopamine replacement therapy (DRT) and had worse sleep, and elevated anxiety, depression and mania scores. Using multiple linear regression analyses, the total anxiety and depression scores, and presence of ICBs were the only variables associated with poorer sleep in PD. PD+ICB patients may show enhanced psychomotor effects of DRT that may in turn contribute to poor sleep quality. Sleep disturbance should be specifically queried in PD+ICB patients.


Assessing reproducibility of a protein dynamics study using in vivo labeling and liquid chromatography tandem mass spectrometry.
Measuring dynamics of proteins abundance in cells in response to stimuli such as growth factors or drugs requires analysis of more than one time point. Proteomic approaches have traditionally been used to measure only one state at a time because quantitation is difficult, especially when mass spectrometry is used as a readout. Isotopically labeled reagents have recently been introduced that allow comparison of two or three different states by mass spectrometry. Here, we evaluate the reproducibility of an experiment that measures three states simultaneously through stable isotope labeling of cells with amino acids in cell culture (SILAC) using light, medium, and heavy versions of amino acids. The major goal of this study was to assess the reproducibility of such experiments in combination with liquid chromatography tandem mass spectrometry (LC-MS/MS). Our results show that it is possible to obtain reproducible quantitative data to study protein dynamics based on our analysis of more than 220 peptide sets derived from 20 proteins from 3 different LC-MS/MS runs.


Variations in the [3H]thymidine labeling of S-phase cells in solid mouse tumors.
To determine whether all tumor S-phase cells incorporate [3H]thymidine, we labeled the cells in three mouse tumors (MCa-11, colon-26, and colon-51) in vivo for 1/2 h with [3H]thymidine (10 microCi/g of body weight). Cells from the tumors, as well as control cells from the bone marrows of the tumor-bearing mice, were then placed onto slides and Feulgen stained. The positions of these Feulgen-stained cells were mapped with a computerized scanning stage, and their nuclear DNA content and nuclear areas were determined by absorption cytophotometry. Next, the slides were processed for autoradiography and exposed for 32 or 64 days to obtain plateau labeling. The cells were then relocated, and the areas of the autoradiographic grains over each nucleus were measured. We found that 99% of the S-phase bone marrow cells were labeled. The 5-mm tumors, however, showed a wide range of S-phase labeling, with 94, 89, and 85% of the MCa-11, colon-51, and colon-26 S-phase cells, respectively, being labeled. The same mice bearing both 5- and 20-mm MCa-11 tumors, however, showed 95 and 57% labeling of the S-phase cells in the small and large tumors, respectively. These results show that the [3H]thymidine labeling of S-phase cells varies greatly for experimental mouse tumors of different size and type, and they suggest that "labeling index" and flow cytometric DNA measurements may not give valid estimates of the actual proportions of cycling S-phase cells in such tumors.


Reversed Frozen Elephant Trunk Technique to Treat a Type II Thoracoabdominal Aortic Aneurysm.
To describe a hybrid technique of reversed frozen elephant trunk to treat thoracoabdominal aortic aneurysms (TAAA) through an abdominal only approach. The technique is demonstrated in a 29-year-old Marfan patient with a chronic type B aortic dissection previously treated with a thoracic stent-graft who presented with a thoracoabdominal false lumen aneurysm. Through an open distal retroperitoneal approach to the abdominal aorta, a frozen elephant trunk graft was implanted over a super-stiff wire upside down with the stent-graft component in the thoracic aorta. Following deployment of the stent-graft proximally and preservation of renovisceral perfusion in a retrograde manner, the renovisceral vessels were sequentially anastomosed to the elephant trunk graft branches, thus reducing the ischemia time of the end organs. The aortic sac was then opened, and the distal part of the hybrid graft was anastomosed with a further bifurcated graft to the iliac vessels. The reversed frozen elephant trunk technique is feasible for hybrid treatment of TAAAs via an abdominal approach only. This has the benefit of substantially reducing the trauma of thoracic exposure, thus preserving major benefits of open thoracoabdominal surgery, such as the presence of short bypasses to the renovisceral vessels and reimplantation of lumbar arteries to reduce spinal cord ischemia.


Imaging Congestion With a Pocket Ultrasound Device: Prognostic Implications in Patients With Chronic Heart Failure.
Venous congestion is common in patients with chronic heart failure (HF). We used a pocket-sized ultrasound imaging device (PID) to assess the patients' congestive status and related our findings to prognosis. One hundred four consecutive outpatients from an HF outpatient clinic were studied. Interstitial lung water (ILW), pleural effusion (PE), and the diameter of the inferior vena cava (VCI) were assessed with the use of a PID. ILW was assessed by demonstration of B-lines (comet tail artifact (CTA). Out of the 104 patients, 28 had CTA and 8 had PE. Median VCI diameter was 18 mm (interquartile range 14-22 mm). Each of these parameters correlated weakly (r = 0.26-0.37; P < .05) with the HF biomarker N-terminal pro-B-type natriuretic peptide (NT-proBNP). During the median follow-up time of 530 days, 18 hospitalizations and 14 deaths were registered. Findings of CTA, PE, or both increased the risk of death or hospitalization (hazard ratio 3-4; P < .05). After adjustment for age, cardiac systolic function, and NT-proBNP, this difference remained significant for CTA alone and CTA + PE combined, but not for PE alone. With the use of a handheld ultrasound device, signs of pulmonary congestion could be demonstrated. When found, these had a significant prognostic impact in clinically stable HF.


In situ ATR-FTIR studies on the competitive adsorption of arsenate and phosphate on ferrihydrite.
In the present study, in situ ATR-FTIR spectroscopy was used for the first time to study the competitive adsorption of phosphate and arsenate on ferrihydrite. Deuterium oxide was used as solvent to facilitate the interpretations of recorded infrared spectra. It was found that arsenate and phosphate adsorbed more strongly at lower pD-values, showing similarities in the adsorption behavior as a function of pD. However, arsenate complexes were found to be more strongly adsorbed than phosphate complexes in the pD range studied. About five times higher concentration of phosphate in solution was needed to reduce the absorbance due to pre-adsorbed arsenate to the same relative level as for pre-adsorbed phosphate, which was desorbed using a solution containing equal (molar) concentrations in arsenate and phosphate. At pD 4, two phosphate complexes were adsorbed on the iron oxide, one deuterated and one de-deuterated. When phosphate was pre-adsorbed and arsenate subsequently added to the system, the deuterated phosphate complex desorbed rapidly while the de-deuterated phosphate complex was quite stable. At pD 8.5, only the de-deuterated phosphate complex was adsorbed on the iron oxide. Moreover, the arsenate adsorbed was also predominantly de-deuterated as opposite to the arsenate adsorbed at pD 4. During the substitution experiments the configuration of these complexes on the iron oxide surface did not change. To the best of our knowledge, this is the first time this difference in stability of the different phosphate complexes is reported and shows the power of employing in situ spectroscopy for this kind of studies.


Maximizing biomass productivity and cell density of Chlorella vulgaris by using light-emitting diode-based photobioreactor.
Green microalgae have recently drawn attention as promising organisms for biofuel production; however, the question is whether they can grow sufficient biomass relative to limiting input factors to be economically feasible. We have explored this question by determining how much biomass the green microalga Chlorella vulgaris can produce in photobioreactors based on highly efficient light-emitting diodes (LEDs). First, growth results were improved under the less expensive light of 660 nm LEDs, developing them in the laboratory to meet the performance levels of the traditional but more expensive 680 nm LEDs by adaptive laboratory evolution (ALE). We then optimized several other key parameters, including input superficial gas velocity, CO(2) concentration, light distribution, and growth media in reference to nutrient stoichiometry. Biomass density thereby rose to approximately 20 g dry-cell-weight (gDCW) per liter (L). Since the light supply was recognized as a limiting factor, illumination was augmented by optimization at systematic level, providing for a biomass productivity of up to 2.11 gDCW/L/day, with a light yield of 0.81 gDCW/Einstein. These figures, which represent the best results ever reported, point to new dimensions in the photoautotrophic performance of microalgal cultures.


Combined Percutaneous Tracheostomy and Endoscopic Gastrostomy Tubes in COVID-19: A Prospective Series of Patient Outcomes.
Background: A significant number of patients with severe respiratory failure related to COVID-19 require prolonged mechanical ventilation. Minimal data exists regarding the timing, safety, and efficacy of combined bedside percutaneous tracheostomy and endoscopy gastrostomy tube placement in these patients. The safety for healthcare providers is also in question. This study's objective was to evaluate the effectiveness and safety of combined bedside tracheostomy and gastrostomy tube placement in COVID-19 patients. Design and Methods: This is a single arm, prospective cohort study in patients with COVID-19 and acute respiratory failure requiring prolonged mechanical ventilation who underwent bedside tracheostomy and percutaneous endoscopic gastrostomy placement. Detailed clinical and procedural data were collected. Descriptive statistics were employed and time to event curves were estimated and plotted using the Kaplan Meier method for clinically relevant prespecified endpoints. Results: Among 58 patients, the median total intensive care unit (ICU) length of stay was 29 days (24.7-33.3) with a median of 10 days (6.3-13.7) postprocedure. Nearly 88% of patients were weaned from mechanical ventilation postprocedure at a median of 9 days (6-12); 94% of these were decannulated. Sixty-day mortality was 10.3%. Almost 90% of patients were discharged alive from the hospital. All procedures were done at bedside with no patient transfer required out of the ICU. A median of 3.0 healthcare personnel total were present in the room per procedure. Conclusion: This study shows that survival of critically ill COVID-19 patients after tracheostomy and gastrostomy was nearly 90%. The time-to-event curves are encouraging regarding time to weaning, downsizing, decannulation, and discharge. A combined procedure minimizes the risk of virus transmission to healthcare providers in addition to decreasing the number of anesthetic episodes, transfusions, and transfers patients must undergo. This approach should be considered in critically ill COVID-19 patients requiring prolonged mechanical ventilation.


Amelioration of cholinergic-induced pancreatitis with a selective cholecystokinin receptor antagonist.
Acute edematous pancreatitis follows excessive cholinergic stimulation in patients exposed to anticholinesterase-containing insecticides. We describe the role of cholecystokinin and the benefits of cholecystokinin receptor blockade in this form of pancreatitis. A cholinergic mimetic (carbachol) was administered to rats weighing 300 to 350 g and produced a form of edematous pancreatitis that mimics that seen in humans. Animals received carbachol intraperitoneally, either alone (250 micrograms/kg of body weight) or with cholecystokinin-receptor antagonist devazepide (3 mg/kg of body weight) and were killed 4 hours later. Carbachol administration resulted in a 19% increase in pancreatic weight, a fourfold increase in serum amylase levels, and a 14-fold increase in serum lipase levels. Plasma cholecystokinin levels, however, were not altered. Devazepide administered prior to cholinergic hyperstimulation blocked pancreatic weight increase and reduced elevations in serum amylase levels twofold and lipase levels fourfold. Although cholecystokinin levels are not elevated in this model of pancreatitis, blockade of even low, background concentrations of this regulatory peptide is beneficial.


[Changes in immunological status among newly-diagnosed HIV-infected in Denmark 1995-2005].
The incidence of new HIV diagnoses in Denmark has remained stable since 1991, but it has increased among the subgroup of homosexual men in recent years. This may reflect an actual increase in newly infected, e.g. as a result of increased risk behaviour, or it may reflect increased HIV testing. To clarify the causes of this increase we describe and analyse the development of HIV infection in Denmark in the period 1995-2005 with special emphasis on the route of transmission, immunological status at the time of diagnosis and the prevalence of patients at risk of transmitting HIV. Observational study based on the Danish HIV Cohort Study, which includes all adults seen at Danish HIV clinics since 1995. From 2000 to 2004 the number of newly-infected homosexual men increased (from 69 to 123), particularly in persons under 30 years (from 5 to 42). The median CD4 cell count at the time of diagnosis increased in this group (median 19.1 cells/microL per year [95% CI: 3.7-11.3]), while it remained stable among heterosexually infected. The number of newly-diagnosed homosexually infected under 30 years with a CD4 cell count over 400 cells/microL increased from 0 in 2000 to 23 in 2004. The prevalence of patients with high viral load (and thus potentially at risk of transmitting HIV) decreased in all risk groups. Newly-diagnosed homosexual men present at an earlier stage of disease progression and with a better preserved immune system today than 5-10 years ago, presumably due to a combination of frequent HIV testing and increased risk behaviour among young homosexuals in particular. Increased preventive measures targeting known risk groups are necessary to prevent further spread.


Standing wave bi-directional linearly moving ultrasonic motor.
A standing wave bi-directional linearly moving ultrasonic motor has been studied for the purpose of implementing a practical linear ultrasonic motor with simple structure, simple driving and high resolution. The fundamental principle of this linear motor is projections on the right sides of a standing wave crests generating thrust force right-diagonally on the slider pressed against the projections. Correspondingly, projections on the left sides of the wave crests make the slider move toward the left. In order to realize bi-directional actuating, vibration mode B3 or B4 is excited in a rectangular plate-type vibrator to make the projections on the right sides or the left sides of the wave crests. In this paper, the operation principle of the linear motor is demonstrated. Furthermore, a prototype linear ultrasonic motor of 40 mm in length, 10 mm in width is fabricated and investigated. The following performances have been achieved: maximum speed 200 mm/s, maximum force output 150 gf, and resolution less than 0.1 microm.


Chemopreventive and chemotherapeutic effect of dietary supplementation of vitamin D on cholangiocarcinoma in a Chemical-Induced animal model.
Intrahepatic cholangiocarcinoma (ICC) is an aggressive cancer. Vitamin D, a pro-hormone, is getting popular due to its hormone-like functions after converted to its active form, 1α,25(OH)2D3. Here, we show that dietary supplementation with 6 IU/g of vitamin D greatly suppressed ICC initiation and progression without apparent toxicity in a chemically induced rat model. Microarray analysis of rat ICC tissues showed vitamin D supplementation modulated the expressions of several unique genes, including lipocalin 2 (Lcn2), confirmed by RT-qPCR and immunohistochemical (IHC) staining. Further, 53 of 80 human ICC specimens (66%) exhibited high LCN2 expression and LCN2 knockdown in SNU308 cells decreased cell growth and migration, suggesting LCN2 be an oncogene in human ICC. As human ICC SNU1079 cells were treated by 1α,25(OH)2D3, LCN2 expression and cell proliferation were attenuated. The downregulation of LCN2 expression was blunted when vitamin D receptor (VDR) was knocked down, implicating that the in vivo Lcn2 downregulation is a direct consequence of vitamin D supplementation Our results support the prevailing concept that vitamin D status is negatively associated with cancer incidence and mortality and suggest LCN2 may be a potential target against ICC. Further studies of application of vitamin D or its analog against ICC are warranted.


Altered ion transport in aortic smooth muscle during deoxycorticosterone acetate hypertension in the rat.
Change in aortic water and electrolyte distribution and in ion turnover were studied during the development of deoxycorticosterone acetate (DOCA) hypertension in the rat. Treatment with DOCA plus saline during the prehypertensive phase was associated with increases in 42K turnover (0.0142 +/- 0.0005 vs. 0.0102 +/- 0.0003 min-1), cell water (0.89 +/- 0.03 vs 0.76 +/- 0.02 kg/kg dry weight), and the ratio of weight to length. These parameters were further increased during the development of hypertension. Significant increases were also observed in total K, Ca, and Mg contents and in Na and C1 contents corrected for the extracellular space. The turnover of 36Cl was increased (0.230 +/- 0.006 vs. 0.136 +/- 0.004 min-1) in DOCA hypertensive rats as was the content of slowly exchanging Cl. Removal of extracellular Ca greatly increased the steady-state turnover of 42K. For control rats, a Ca concentration of 0.1 mM reduced the rate of 42K turnover to less than 50% of the Ca-free value (0.063 +/- 0.004 min-1), whereas DOCA hypertensive rats exhibited only a 10% reduction. At the highest Ca concentration, 5 mM, the 42K turnover was greater in DOCA-treated rats with the hypertensives operating at 67% of maximum efflux or about twice the efflux in controls. It is concluded that significant alterations in ion transport by vascular smooth muscle occur before and during the development of hypertension induced by treatment with DOCA plus saline. Such changes may result from a reduced ability of Ca to stabilize the membrane. It is proposed that such alterations contribute to the changes in vascular reactivity and the hypertrophy associated with hypertension.


Public Response to a Social Media Tobacco Prevention Campaign: Content Analysis.
Prior research suggests that social media-based public health campaigns are often targeted by countercampaigns. Using reactance theory as the theoretical framework, this research characterizes the nature of public response to tobacco prevention messages disseminated via a social media-based campaign. We also examine whether agreement with the prevention messages is associated with comment tone and nature of the contribution to the overall discussion. User comments to tobacco prevention messages, posted between April 19, 2017 and July 12, 2017, were extracted from Twitter, Facebook, and Instagram. Two coders categorized comments in terms of tone, agreement with message, nature of contribution, mentions of government agency and regulation, promotional or spam comments, and format of comment. Chi-square analyses tested associations between agreement with the message and tone of the public response and the nature of contributions to the discussions. Of the 1242 comments received (Twitter: n=1004; Facebook: n=176; Instagram: n=62), many comments used a negative tone (42.75%) and disagreed with the health messages (39.77%), while the majority made healthy contributions to the discussions (84.38%). Only 0.56% of messages mentioned government agencies, and only 0.48% of the comments were antiregulation. Comments employing a positive tone (84.13%) or making healthy contributions (69.11%) were more likely to agree with the campaign messages (P=0.01). Comments employing a negative tone (71.25%) or making toxic contributions (36.26%) generally disagreed with the messages (P=0.01). The majority of user comments in response to a tobacco prevention campaign made healthy contributions. Our findings encourage the use of social media to promote dialogue about controversial health topics such as smoking. However, toxicity was characteristic of comments that disagreed with the health messages. Managing negative and toxic comments on social media is a crucial issue for social media-based tobacco prevention campaigns to consider.


Back-extrapolated and year-specific NO2 land use regression models for Great Britain - Do they yield different exposure assessment?
Robust methods to estimate historic population air pollution exposures are important tools for epidemiological studies evaluating long-term health effects. We developed land use regression (LUR) models for NO2 exposure in Great Britain for 1991 and explored whether the choice of year-specific or back-extrapolated LUR yields 1) similar LUR variables and model performance, and 2) similar national and regional address-level and small-area concentrations. We constructed two LUR models for 1991using NO2 concentrations from the diffusion tube monitoring network, one using 75% of all available measurement sites (that over-represent industrial areas), and the other using 75% of a subset of sites proportionate to population by region to study the effects of monitoring site selection bias. We compared, using the remaining (hold-out) 25% of monitoring sites, the performance of the two 1991 models with back-extrapolation of a previously published 2009 model, developed using NO2 concentrations from automatic chemiluminescence monitoring sites and predictor variables from 2006/2007. The 2009 model was back-extrapolated to 1991 using the same predictors (1990 & 1995) used to develop 1991 models. The 1991 models included industrial land use variables, not present for 2009. The hold-out performance of 1991 models (mean-squared-error-based-R(2): 0.62-0.64) was up to 8% higher and ~1μg/m(3) lower in root mean squared error than the back-extrapolated 2009 model, with best performance from the subset of sites representing population exposures. Year-specific and back-extrapolated exposures for residential addresses (n=1.338,399) and small areas (n=10.518) were very highly linearly correlated for Great Britain (r>0.83). This study suggests that year-specific model for 1991 and back-extrapolation of the 2009 LUR yield similar exposure assessment.


[Characterization of compounds in crude oils by gas purge micro-syringe extraction coupled to comprehensive two-dimensional gas chromatography].
A novel sample pretreatment method, gas purge micro-syringe extraction (GP- MSE), coupled to comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC x GC/TOFMS) has been developed for the characterization of volatile and semi-volatile compounds in crude oils. In the sample pretreatment process, the analytes were carried to the microsyringe barrel by inert gas, and at the same time, trapped by an organic solvent. The whole process of extraction takes less than 10 min, and only 20 μL of organic solvent was needed. Using two custom standard solutions containing alkanes and polycyclic aromatic hydrocarbons (PAHs), the influences of the extraction conditions were investigated. The optimized conditions were as follows: 5 mg crude oil, 20 μL hexane (extraction solvent), extraction for 3 min at 300 °C, condensation temperature set at -2 °C, gas flow rate set at 2 mL/min. Under the optimized conditions, a real crude oil sample was extracted and then analyzed in detail. It showed that the proposed method was very effective in simultaneously analyzing the normal and branched alkanes, cycloalkanes, aromatic hydrocarbons, and biomarkers of crude oil such as steranes and terpanes. The recoveries obtained ranged from 82.0% to 107.3% and the detection limits ranged from 34 to 93 μg/L. The correlation coefficients (R2) were more than 0.99. The relative standard deviations (RSDs, n = 5) for all the analytes were below 10%. The results indicate that the proposed method is suitable for the characterization of volatile and semi-volatile compounds in crude oils with easy operation, high sensitivity and efficiency.


Analysis of glucocorticoid and mineralocorticoid signalling by gene targeting.
To get a better understanding of the role of glucocorticoid and mineralocorticoid signalling during development and in whole animal physiology, we have disrupted the mouse glucocorticoid and mineralocorticoid receptor gene by gene targeting. Most of the mice with a disrupted glucocorticoid receptor gene die within the first hours after birth due to severe lung atelectasis. Perinatal induction of gluconeogenic enzymes in the liver is impaired. Feed back control of the glucocorticoid synthesis via the hypothalamic-pituitary-adrenal axis is perturbed leading to increased plasma levels of corticosterone and adrenocorticotrophic hormone. Increased activity of the hypothalamic-pituitary-adrenal axis results in extensive hypertrophy and hyperplasia of the cortical zones of the adrenal and induction of genes involved in steroid biosynthesis. The adrenal medulla is disorganized and severely reduced in size; cells capable of adrenaline synthesis are missing. Mineralocorticoid receptor deficient mice die around day 10 after birth. Weight loss precedes death of homozygous mutant mice and is correlated with an increase in the haematocrit. As a consequence of this mutation plasma levels of renin, angiotensin II, and aldosterone are highly elevated.


PSD-95 is required to sustain the molecular organization of the postsynaptic density.
PSD-95, a membrane-associated guanylate kinase, is the major scaffolding protein in the excitatory postsynaptic density (PSD) and a potent regulator of synaptic strength. Here we show that PSD-95 is in an extended configuration and positioned into regular arrays of vertical filaments that contact both glutamate receptors and orthogonal horizontal elements layered deep inside the PSD in rat hippocampal spine synapses. RNA interference knockdown of PSD-95 leads to loss of entire patches of PSD material, and electron microscopy tomography shows that the patchy loss correlates with loss of PSD-95-containing vertical filaments, horizontal elements associated with the vertical filaments, and putative AMPA receptor-type, but not NMDA receptor-type, structures. These observations show that the orthogonal molecular scaffold constructed from PSD-95-containing vertical filaments and their associated horizontal elements is essential for sustaining the three-dimensional molecular organization of the PSD. Our findings provide a structural basis for understanding the functional role of PSD-95 at the PSD.


Infrared and Raman Diagnostic Modeling of Phosphate Adsorption on Ceria Nanoparticles.
Cerium dioxide (CeO2; ceria) nanoparticles (CeNPs) are promising nanozymes that show a variety of biological activity. Effective nanozymes need to retain their activity in the face of surface speciation in biological environments, and characterizing surface speciation is therefore critical to understanding and controlling the therapeutic capabilities of CeNPs. In particular, adsorbed phosphates can impact the enzymatic activity exploited to convert phosphate prodrugs into therapeutics in vivo and also define the early stages of the phosphate-scavenging processes that lead to the transformation of active CeO2 into inactive CePO4. In this work, we utilize ab initio lattice-dynamics calculations to study the interaction of phosphates with the three major surfaces of ceria and to predict the infrared (IR) and Raman spectral signatures of adsorbed phosphate species. We find that phosphates adsorb strongly to CeO2 surfaces in a range of stable binding configurations, of which 5-fold coordinated P species in a trigonal bipyramidal coordination may represent a stable intermediate in the early stages of phosphate scavenging. We find that the phosphate species show characteristic spectral fingerprints between 500 and 1500 cm-1, whereas the bare CeO2 surfaces show no active modes above 600 cm-1, and the 5-fold coordinated P species in particular show potential diagnostic P-O stretching modes between 650 and 700 cm-1 in both IR and Raman spectra. This comprehensive exploration of different binding modes for phosphates on CeO2 and the set of reference spectra provides an important step toward the experimental characterization of phosphate speciation and, ultimately, control of its impact on the performance of ceria nanozymes.


Toxicological considerations in the application and interpretation of susceptibility biomarkers in epidemiological studies.
With major advances in genotyping technology, it has become practical and affordable to screen biological samples for multiple polymorphisms for which there is more or less knowledge about their functional relevance in relation to toxicological agents or disease. This situation creates some unique epidemiological challenges in which careful consideration of the mechanisms underlying genotype-disease and genotype-exposure-disease relationships, or the lack of knowledge thereof, may help to prevent false-positive results or misinterpretation of data that could mislead future research. Coordination and linkage of data resources on toxicological exposures, genes and disease would be useful as an integrated source of information to devise study design, analysis and interpretation. Such a database could be useful in collating information from which to determine relevant exposures for the disease and to guide the selection of susceptibility markers for study. Further information on toxicological mechanisms and functional relevance of gene variants in relation to disease could be accounted for in statistical analyses and interpretation. Statistical methods that can incorporate this prior information on mechanism, such as hierarchical regression modelling, may help to mitigate some of the problems inherent to these studies by adjusting estimates and confidence limits according to this prior information. Even in the situation where little information on etiological mechanisms is available, application of a less informed prior can be beneficial in improving the accuracy and precision for an ensemble of estimates. The changing paradigm of epidemiological research with regard to increasing detail of underlying mechanisms and the sheer amount of data being evaluated necessitates access to sources of information and analytic methods that can integrate this complexity.


Federal Trade Commission drops challenge to California hospital acquisition.
The significance of patient outmigration patterns, third-party payor reaction, and post-merger cost savings have been regularly argued by defense counsel and hospitals as important consideration in the antitrust evaluation of hospital mergers. The reliance placed by the Commission on these factors in its Ukiah decision is a welcome confirmation that the antitrust agencies are increasingly sensitive to these aspects of hospital mergers, reflecting a more sophisticated understanding of the health care market than was suggested by the staff's more mechanical evaluative approach. Hospitals and their counsel should therefore prepare for and document these factors if they anticipate antitrust agency scrutiny of a proposed acquisition or merger.


A dietary dairy/yeast prebiotic and flaxseed oil enhance growth, hematological and immunological parameters in channel catfish at a suboptimal temperature (15°C).
Channel catfish raised in the southern United States require two growing seasons to reach market size. Growing seasons are separated by a cool period of about 3 months when feed intake and growth are greatly reduced. A cool-weather feeding strategy to improve feed intake, growth or health of catfish might improve survival and reduce the time needed to achieve market size. We conducted a feeding trial with channel catfish at a suboptimal temperature (15°C) to determine the effects of supplementing diets with either a dairy/yeast prebiotic or flaxseed oil (high in 18:3n-3) compared with a control with soybean oil (high in 18:2n-6). The trial was conducted in recirculating systems with 1140-l tanks containing 100 fish each (mean initial weight 61.4 g±0.43 s.e.m.). A 28%-protein basal diet was supplemented with 20 g/kg cellulose and 20 g/kg soybean oil (SBO, control), 20 g/kg cellulose and 20 g/kg flaxseed oil (FLAX) or 20 g/kg of a dairy/yeast prebiotic and 20 g/kg soybean oil (PREB). Fish were fed once daily to satiation and weighed every 3 weeks to track growth. Hematology, non-specific immune responses, proximate and fatty acid composition of muscle were determined to assess diet effects. Catfish-fed FLAX or PREB had higher weight gain, feed consumption and lysozyme activity than fish fed SBO. Total n-3 fatty acids in muscle were higher in fish fed SBO or FLAX than those fed PREB. Total n-6 long-chain polyunsaturated acids were higher in muscle of fish fed PREB than those fed SBO. Fatty acids in the PREB and SBO diets were similar, so the PREB appeared to increase elongation and desaturation of n-6 fatty acids in muscle. Flaxseed oil and the dairy/yeast prebiotic both have potential to increase catfish performance at a low temperature.


Vascular pathology of medial arterial calcifications in NT5E deficiency: implications for the role of adenosine in pseudoxanthoma elasticum.
Arterial Calcification due to Deficiency of CD73 (ACDC) results from mutations in the NT5E gene encoding the 5' exonucleotidase, CD73. We now describe the third familial case of ACDC, including radiological and histopathological details of the arterial calcifications. The medial lesions involve the entire circumference of the elastic lamina, in contrast to the intimal plaque-like disease of atherosclerosis. The demonstration of broken and fragmented elastic fibers leading to generalized vascular calcification suggests an analogy to pseudoxanthoma elasticum (PXE), which exhibits similar histopathology. Classical PXE is caused by deficiency of ABCC6, a C type ABC transporter whose ligand is unknown. Other C type ABC proteins transport nucleotides, so the newly described role of adenosine in inhibiting vascular calcification, along with the similarity of ACDC and PXE with respect to vascular pathology, suggests that adenosine may be the ligand for ABCC6.


It Is Time to Revitalize the Antibiotic Pipeline: Systems Ecology Can Help.
Antimicrobials have been known for millennia, but innovative antibiotics are currently in short supply. New antimicrobial discoveries are being threatened by planetary scale loss of biodiversity that has important impacts on species and ecosystems. This expert review underscores that microorganisms in nature and their diversity are essential cornerstones to revitalize the antibiotic innovation and discovery pipeline. The recent rise of systems ecology and planetary health offers new and actionable potentials in this regard. Without a systems scale focus and appreciation of systems ecology, the global threats to human and planetary health from inappropriate use of antibiotics and antimicrobial resistance will continue to escalate with serious consequences to all life on the planet. With acutely pressing research and development needs to revitalize antibiotic treatment and novel diagnostic tools for personalized medicine, national health systems ought to work across knowledge silos not only within but also across the ministries, for example, health, agriculture, environment, economy, trade, and social services ministries that collectively impact on systems ecology and by extension on health innovations including the antibiotic discovery pipeline. Such systems vision can also help to revitalize antibiotic discovery pipeline as most antibiotics have natural origins or have designs inspired or based on molecules in the environment and microorganisms that produce antibiotics. Above all, our audience and responsibility include every person who has an interest in his or her own health, in the health of his or her fellow human beings and all life on the planet, and in the health of future generations.


Molecular interactions between the specialist herbivore Manduca sexta (Lepidoptera, Sphingidae) and its natural host Nicotiana attenuata. IV. Insect-Induced ethylene reduces jasmonate-induced nicotine accumulation by regulating putrescine N-methyltransferase transcripts.
Attack by the specialist herbivore, Manduca sexta, on its native host Nicotiana attenuata Torr. ex Wats. produces a dramatic ethylene release, a jasmonate burst, and a suppression of the nicotine accumulation that results from careful simulations of the herbivore's damage. Methyl-jasmonate (MeJA) treatment induces nicotine biosynthesis. However, this induction can be suppressed by ethylene as pretreatment of plants with 1-methylcyclopropene (1-MCP), a competitive inhibitor of ethylene receptors, restores the full MeJA-induced nicotine response in herbivore attacked plants (J. Kahl, D.H. Siemens, R.J. Aerts, R. Gäbler, F. Kühnemann, C.A. Preston, I.T. Baldwin [2000] Planta 210: 336-342). To understand whether this herbivore-induced signal cross-talk occurs at the level of transcript accumulation, we cloned the putrescine methyltransferase genes (NaPMT1 and NaPMT2) of N. attenuata, which are thought to represent the rate limiting step in nicotine biosynthesis, and measured transcript accumulations by northern analysis after various jasmonate, 1-MCP, ethephon, and herbivory treatments. Transcripts of both root putrescine N-methyltransferase (PMT) genes and nicotine accumulation increased dramatically within 10 h of shoot MeJA treatment and immediately after root treatments. Root ethephon treatments suppressed this response, which could be reversed by 1-MCP pretreatment. Moreover, 1-MCP pretreatment dramatically amplified the transcript accumulation resulting from both wounding and M. sexta herbivory. We conclude that attack from this nicotine-tolerant specialist insect causes N. attenuata to produce ethylene, which directly suppresses the nitrogen-intensive biosynthesis of nicotine.


The interaction of encephalomyocarditis virus with its erythrocyte receptor on affinity chromatography columns.
Glycophorin, the major sialoglycoprotein in the human erythrocyte surface membrane, can serve as a red cell receptor for both wheat-germ agglutinin (WGA) and encephalomyocarditis (EMC) virus since glycophorin bound to WGA--Sepharose can at the same time bind EMC virus. In contrast, glycophorin bound to WGA--Sepharose cannot bind EMC virus in the presence of SDS. The evidence suggests that virus binding to glycophorin-WGA--Sepharose occurred in the absence of SDS because glycophorin was present in aggregated complexes which were large enough either to accommodate both EMC virus and WGA at the same time, or alternatively to provide sufficient attachment sites for multivalent binding of virions.


Automated Generation of Core Outcome Measures for Clinical Trials.
Common outcome sets are vital for ensuring usability of clinical trial results and enabling inter-study comparisons. The task of identifying clinical outcomes for a particular field is cumbersome and time-consuming. The aim of this work was to develop an automated pipeline for identifying common outcomes by analyzing outcomes from relevant trials reported at ClinicalTrials.gov and to assess the pipeline accuracy. We validated the output of our pipeline by comparing the outcomes it identified for acute coronary syndromes and coronary artery disease with the set of outcomes recommended for these conditions by a panel of experts in a widely cited report. We found that our pipeline identified the same or similar outcomes for 100% of the outcomes recommended in the experts' report. The coverage of the pipeline's results dropped only slightly (to 21 out of 23 outcome domains, 91%) when we restricted the pipeline to trials posted before the publication of the report, indicating a great potential for this pipeline to be used in aiding and informing the future development of core outcome measures in clinical trials.


Physiochemical characterization of the nisin-membrane interaction with liposomes derived from Listeria monocytogenes.
Mechanistic information about the bacteriocin nisin was obtained by examining the efflux of 5(6)-carboxy-fluorescein from Listeria monocytogenes-derived liposomes. The initial leakage rate (percentage of efflux per minute) of the entrapped dye was dependent on both nisin and lipid concentrations. At all nisin concentrations tested, 5(6)-carboxyfluorescein efflux plateaued before all of the 5(6)-carboxyfluorescein was released (suggesting that pore formation was transient), but efflux resumed when more nisin was added. Isotherms for the binding of nisin to liposomes constructed on the basis of the Langmuir isotherm gave an apparent binding constant of 6.2 x 10(5)M(-1) at pH 6.0. The critical number of nisin molecules required to induce efflux from liposomes at pH 6.0 was approximately 7,000 molecules per liposome. The pH affected the 5(6)-carboxyfluorescein leakage rates, with higher pH values resulting in higher leakage rates. The increased leakage rate observed at higher pH values was not due to an increase in the binding affinity of the nisin molecules towards the liposomal membrane. Rather, the critical number of nisin molecules required to induce activity was decreased (approximately 1,000 nisin molecules per liposome at pH 7.0). These data are consistent with a poration mechanism in which the ionization state of histidine residues in nisin plays an important role in membrane permeabilization.


Injury in Brazilian Jiu-Jitsu Training.
Brazilian jiu-jitsu (BJJ) is a grappling-based martial art that can lead to injuries both in training and in competition. There is a paucity of data regarding injuries sustained while training in BJJ, in both competitive and noncompetitive jiu-jitsu athletes. We hypothesize that most BJJ practitioners sustain injuries to various body locations while in training and in competition. Our primary objective was to describe injuries sustained while training for BJJ, both in practice and in competition. Our secondary objectives were to classify injury type and to explore participant and injury characteristics associated with wanting to quit jiu-jitsu after injury. Descriptive epidemiology study. We conducted a survey of all BJJ participants at a single club in Hamilton, Ontario, Canada. We developed a questionnaire including questions on demographics, injuries in competition and/or training, treatment received, and whether the participant considered discontinuing BJJ after injury. A total of 70 BJJ athletes participated in this study (response rate, 85%). Ninety-one percent of participants were injured in training and 60% of competitive athletes were injured in competitions. Significantly more injuries were sustained overall for each body region in training in comparison with competition (P < 0.001). Two-thirds of injured participants required medical attention, with 15% requiring surgery. Participants requiring surgical treatment were 6.5 times more likely to consider quitting compared with those requiring other treatments, including no treatment (odds ratio [OR], 6.50; 95% CI, 1.53-27.60). Participants required to take more than 4 months off training were 5.5 times more likely to consider quitting compared with those who took less time off (OR, 5.48; 95% CI, 2.25-13.38). The prevalence of injury is very high among BJJ practitioners, with 9 of 10 practitioners sustaining at least 1 injury, commonly during training. Injuries were primarily sprains and strains to fingers, the upper extremity, and neck. Potential participants in BJJ should be informed regarding significant risk of injury and instructed regarding appropriate precautions and safety protocols. Clinicians should be aware of the substantial risk of injury among BJJ practitioners and the epidemiology of the injuries as outlined in this article.


A Multicenter Comparison of Open Versus Arthroscopic Fixation for Pediatric Tibial Spine Fractures.
When operative treatment is indicated, tibial spine fractures can be successfully managed with open or arthroscopic reduction and internal fixation (ARIF). The purpose of the study is to evaluate short-term treatment outcomes of tibial spine fractures in patients treated with both open and arthroscopic fracture reduction. We performed an Institutional Review Board (IRB)-approved retrospective cohort study of pediatric tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients were categorized into 2 cohorts based on treatment: ARIF and open reduction and internal fixation (ORIF). Short-term surgical outcomes, the incidence of concomitant injuries, and surgeon demographics were compared between groups. There were 477 patients with tibial spine fractures who met inclusion criteria, 420 of whom (88.1%) were treated with ARIF, while 57 (11.9%) were treated with ORIF. Average follow-up was 1.12 years. Patients treated with ARIF were more likely to have an identified concomitant injury (41.4%) compared with those treated with ORIF (24.6%, P=0.021). Most concomitant injuries (74.5%) were treated with intervention. The most common treatment complications included arthrofibrosis (6.9% in ARIF patients, 7.0% in ORIF patients, P=1.00) and subsequent anterior cruciate ligament injury (2.1% in ARIF patients and 3.5% in ORIF, P=0.86). The rate of short-term complications, return to the operating room, and failure to return to full range of motion were similar between treatment groups. Twenty surgeons with sports subspecialty training completed 85.0% of ARIF cases; the remaining 15.0% were performed by 12 surgeons without additional sports training. The majority (56.1%) of ORIF cases were completed by 14 surgeons without sports subspecialty training. This study demonstrated no difference in outcomes or nonunion following ARIF or ORIF, with a significantly higher rate of concomitant injuries identified in patients treated with ARIF. The majority of identified concomitant injuries were treated with surgical intervention. Extensive surgical evaluation or pretreatment magnetic resonance imaging should be considered in the workup of tibial spine fractures to increase concomitant injury identification. Level III.


The measurement of systemic arterial blood pressure.
The measurement of blood pressure, sphygmomanometry, can provide much significant information for the optometrist's evaluation of his patient's ocular and related systemic conditions when the principles involved are understood and skill in its measurement is achieved. This paper will discuss the procedural details of blood pressure measurement.


Transformation of elemental mercury by bacteria.
The fate and impact of elemental mercury in closed bacterial cultures were examined. The quantity of elemental mercury oxidized by bacteria ranged from small amounts for Pseudomonas aeruginosa, P. fluorescens, Escherichia coli, and Citrobacter to essentially all of the added elemental mercury for Bacillus subtilis and B. megaterium. The percentage of the total mercury in the system associated with bacterial cells ranged from 18.6 to 43.2%. Growth of the two Pseudomonas species was inhibited by elemental mercury, whereas growth of the other cultures was not distinguishable from that in mercury-free controls. No methylmercury was formed by the six cultures within 48 h.


Does the ovarian cycle influence the pressure-pain threshold of the masticatory muscles in symptom-free women?
To test the hypothesis that the ovarian cycle influences the pressure-pain threshold of the masticatory muscles. Eighteen healthy women with a regular menstrual cycle (28 +/- 2 days), ranging in age from 18 to 35 years, participated in the study. For each subject, pressure-pain thresholds (PPTs) of the masseter and temporalis muscles were assessed at 4 muscular sites by means of an electronic algometer. Measurements were taken at 4 separate sessions across the menstrual cycle corresponding to the following phases: menstrual, follicular, periovulatory, and luteal. Menstrual cycle phases were determined by a pelvic ultrasonographic screening. The study was carried out in a single-blind design, and the initial session was randomly determined for each individual. Data collected were analyzed by repeated-measures analysis of variance. The findings suggest that the PPTs of several masticatory muscles (2 of 4) are influenced by the ovarian cycle, but to a minor extent (P < 0.05), and the influence is of limited clinical relevance. In healthy subjects, there is a link between mechanical sensitivity of the masticatory muscles and fluctuation of the ovarian hormones. The relationship between PPTs of the masticatory muscles and the ovarian cycle should be also investigated in patients with temporomandibular disorders and/or orofacial pain conditions.


Publication activities relating to digital teaching and learning in the GMS Journal for Medical Education - a descriptive analysis (1984-2020).
Digital teaching, learning and assessment have been part of medical education and continuing education for decades. The objective of this review paper is to highlight developments and perspectives in these areas in the GMS Journal for Medical Education (GMS JME). In the spring of 2020, we conducted a systematic literature search of the Journal for Medical Education (JME) and analysed the articles with regard to different categories such as article type, digital tools used or mode of data collection. Of the 132 articles analysed, 78 were digital interventions (53 of which were exploratory-descriptive), 28 were project descriptions, 16 were surveys of needs or equipment and 10 were concept papers. About one-third of the studies and project reports each dealt with virtual patients or case-based learning, whereas no articles were published on trends such as serious games or virtual reality. Overall, our analysis shows that in many respects, the studies on digital teaching were more broadly based, especially between 2006 and 2010, after which this trend tended to decline again. Our analysis shows that publications in the JME consider some key aspects of digital teaching in medical education and continuing education, such as educational videos or virtual patients. The variability of information and methods of presentation advocate the use of guidelines to optimise the quality of scientific papers. Furthermore, clues for future research topics and experimental study designs are identified.


Genomic testing, tumor microenvironment and targeted therapy of Hedgehog-related human cancers.
Hedgehog signals are transduced through Patched receptors to the Smoothened (SMO)-SUFU-GLI and SMO-Gi-RhoA signaling cascades. MTOR-S6K1 and MEK-ERK signals are also transduced to GLI activators through post-translational modifications. The GLI transcription network up-regulates target genes, such as BCL2, FOXA2, FOXE1, FOXF1, FOXL1, FOXM1, GLI1, HHIP, PTCH1 and WNT2B, in a cellular context-dependent manner. Aberrant Hedgehog signaling in tumor cells leads to self-renewal, survival, proliferation and invasion. Paracrine Hedgehog signaling in the tumor microenvironment (TME), which harbors cancer-associated fibroblasts, leads to angiogenesis, fibrosis, immune evasion and neuropathic pain. Hedgehog-related genetic alterations occur frequently in basal cell carcinoma (BCC) (85%) and Sonic Hedgehog (SHH)-subgroup medulloblastoma (87%) and less frequently in breast cancer, colorectal cancer, gastric cancer, pancreatic cancer, non-small-cell lung cancer (NSCLC) and ovarian cancer. Among investigational SMO inhibitors, vismodegib and sonidegib are approved for the treatment of patients with BCC, and glasdegib is approved for the treatment of patients with acute myeloid leukemia (AML). Resistance to SMO inhibitors is caused by acquired SMO mutations, SUFU deletions, GLI2 amplification, other by-passing mechanisms of GLI activation and WNT/β-catenin signaling activation. GLI-DNA-interaction inhibitors (glabrescione B and GANT61), GLI2 destabilizers (arsenic trioxide and pirfenidone) and a GLI-deacetylation inhibitor (4SC-202) were shown to block GLI-dependent transcription and tumorigenesis in preclinical studies. By contrast, SMO inhibitors can remodel the immunosuppressive TME that is dominated by M2-like tumor-associated macrophages (M2-TAMs), myeloid-derived suppressor cells and regulatory T cells, and thus, a Phase I/II clinical trial of the immune checkpoint inhibitor pembrolizumab with or without vismodegib in BCC patients is ongoing.


LazySampling and LinearSampling: Fast Stochastic Sampling of RNA Secondary Structure with Applications to SARS-CoV-2.
Many RNAs fold into multiple structures at equilibrium. The classical stochastic sampling algorithm can sample secondary structures according to their probabilities in the Boltzmann ensemble, and is widely used. However, this algorithm, consisting of a bottom-up partition function phase followed by a top-down sampling phase, suffers from three limitations: (a) the formulation and implementation of the sampling phase are unnecessarily complicated; (b) the sampling phase repeatedly recalculates many redundant recursions already done during the partition function phase; (c) the partition function runtime scales cubically with the sequence length. These issues prevent stochastic sampling from being used for very long RNAs such as the full genomes of SARS-CoV-2. To address these problems, we first adopt a hypergraph framework under which the sampling algorithm can be greatly simplified. We then present three sampling algorithms under this framework, among which the LazySampling algorithm is the fastest by eliminating redundant work in the sampling phase via on-demand caching. Based on LazySampling, we further replace the cubic-time partition function by a linear-time approximate one, and derive LinearSampling, an end-to-end linear-time sampling algorithm that is orders of magnitude faster than the standard one. For instance, LinearSampling is 176Ã- faster (38.9s vs. 1.9h) than Vienna RNAsubopt on the full genome of Ebola virus (18,959 nt ). More importantly, LinearSampling is the first RNA structure sampling algorithm to scale up to the full-genome of SARS-CoV-2 without local window constraints, taking only 69.2 seconds on its reference sequence (29,903 nt ). The resulting sample correlates well with the experimentally-guided structures. On the SARS-CoV-2 genome, LinearSampling finds 23 regions of 15 nt with high accessibilities, which are potential targets for COVID-19 diagnostics and drug design. See code: https://github.com/LinearFold/LinearSampling.


Gap junction proteins in the blood-brain barrier control nutrient-dependent reactivation of Drosophila neural stem cells.
Neural stem cells in the adult brain exist primarily in a quiescent state but are reactivated in response to changing physiological conditions. How do stem cells sense and respond to metabolic changes? In the Drosophila CNS, quiescent neural stem cells are reactivated synchronously in response to a nutritional stimulus. Feeding triggers insulin production by blood-brain barrier glial cells, activating the insulin/insulin-like growth factor pathway in underlying neural stem cells and stimulating their growth and proliferation. Here we show that gap junctions in the blood-brain barrier glia mediate the influence of metabolic changes on stem cell behavior, enabling glia to respond to nutritional signals and reactivate quiescent stem cells. We propose that gap junctions in the blood-brain barrier are required to translate metabolic signals into synchronized calcium pulses and insulin secretion.


Corticospinal adaptations and strength maintenance in the immobilized arm following 3 weeks unilateral strength training.
Cross-education strength training has being shown to retain strength and muscle thickness in the immobilized contralateral limb. Corticospinal mechanisms have been proposed to underpin this phenomenon; however, no transcranial magnetic stimulation (TMS) data has yet been presented. This study used TMS to measure corticospinal responses following 3 weeks of unilateral arm training on the contralateral, immobilize arm. Participants (n = 28) were randomly divided into either immobilized strength training (Immob + train) immobilized no training (Immob) or control. Participants in the immobilized groups had their nondominant arm rested in a sling, 15 h/day for 3 weeks. The Immob + train group completed unilateral arm curl strength training, while the Immob and control groups did not undertake training. All participants were tested for corticospinal excitability, strength, and muscle thickness of both arms. Immobilization resulted in a group x time significant reduction in strength, muscle thickness and corticospinal excitability for the untrained limb of the Immob group. Conversely, no significant change in strength, muscle thickness, or corticospinal excitability occurred in the untrained limb of the Immob + train group. These results provide the first evidence of corticospinal mechanisms, assessed by TMS, underpinning the use of unilateral strength training to retain strength and muscle thickness following immobilization of the contralateral limb.


Patients' willingness to accept the risks and benefits of new treatments for chronic hepatitis C virus infection.
Some patients with chronic hepatitis C virus (HCV) infection forego treatment due to concerns about treatment efficacy, treatment duration, and side effects. The purpose of this study was to quantify patient preferences among possible outcomes associated with new, direct-acting antiviral agents (DAAs) for the treatment of HCV infection and determine which treatment features are most important to patients in making treatment decisions. Adult participants with a self-reported physician diagnosis of HCV infection in five countries completed a web-enabled, choice-format conjoint analysis survey. The survey presented participants with 20 treatment-choice questions. Each treatment-choice question included a pair of hypothetical treatment profiles with varying levels of six attributes: treatment duration; chance of getting rid of the virus completely (i.e. likelihood of a sustained virologic response [SVR]); weeks on an additional, third medicine (i.e. a DAA); risk of a severe rash; risk of severe anemia; and number of times a day the third medicine is taken. Treatment-choice questions were based on a pre-determined experimental design with known statistical properties. Random-parameters logit was used to estimate preference weights for all attribute levels and the mean relative importance of each attribute. 284 participants completed the survey. Likelihood of an SVR was the most important outcome to participants, followed by severe anemia risk, severe rash risk, therapy type (a combination of total weeks of treatment and weeks on the third medicine), and dosing of the third medicine. Controlling for other factors, preferences were similar across all therapy types examined. Patients with HCV infection indicate a willingness to accept an increased risk of side effects for sufficient improvement in the likelihood of treatment response.


Survival and transfer of murine norovirus 1, a surrogate for human noroviruses, during the production process of deep-frozen onions and spinach.
The reduction of murine norovirus 1 (MNV-1) on onions and spinach by washing was investigated as was the risk of contamination during the washing procedure. To decontaminate wash water, the industrial sanitizer peracetic acid (PAA) was added to the water, and the survival of MNV-1 was determined. In contrast to onions, spinach undergoes a heat treatment before freezing. Therefore, the resistance of MNV-1 to blanching of spinach was examined. MNV-1 genomic copies were detected with a real-time reverse transcription PCR assay in PAA-treated water and blanched spinach, and PFUs (representing infectious MNV-1 units) were determined with a plaque assay. A < or = 1-log reduction in MNV-1 PFUs was achieved by washing onion bulbs and spinach leaves. More than 3 log PFU of MNV-1 was transmitted to onion bulbs and spinach leaves when these vegetables were washed in water containing approximately 5 log PFU/ml. No decline of MNV-1 occurred in used industrial spinach wash water after 6 days at room temperature. A concentration of 20 ppm of PAA in demineralized water (pH 4.13) and in potable water (pH 7.70) resulted in reductions of 2.88 +/- 0.25 and 2.41 +/- 0.18 log PFU, respectively, after 5 min of exposure, but no decrease in number of genomic copies was observed. No reduction of MNV-1 PFUs was observed on frozen onions or spinach during storage for 6 months. Blanching spinach (80 degrees C for 1 min) resulted in at least 2.44-log reductions of infectious MNV-1, but many genomic copies were still present.


Selection toward shorter flowers by butterflies whose probosces are shorter than floral tubes.
Darwin's meticulous observations on the function of floral shape led to his famous prediction of a long-tongued pollinator, which he believed to be the evolutionary trigger for the long-spurred flowers of the Madagascar star orchid. Although tubular flowers are common, long tubes or spurs are an exception, suggesting that selection maintaining short flowers is widespread. Using the butterfly-pollinated carnation Dianthus carthusianorum and two butterfly species differing in proboscis length (Melanargia galathea and Inachis io) as model organisms, we experimentally demonstrate a reduction in pollinator efficiency with an increasing difference between proboscis length and floral tube length. Such a relationship is a prerequisite for the evolution of floral shape in response to pollinator morphology.


Type IV reactions in the skin.
Delayed type (Type IV) hypersensitivity is commonly manifested in clinical practice as allergic eczematous contact dermatitis (AECD). This reaction can be transferred by lymphoid cells but not serum and parallels other T lymphocyte immune responses. Recent evidence correlates the sensitization phase of AECD with in vitro lymphocyte transformation and the elicitation phase with lymphokine activity. Although a bewildering variety of haptens may be responsible for AECD, they have in common an ability to form co-valent bonds with proteins. Patch testing with the offending antigen will reproduce the disease. Therapy of choice remains topical or systemic corticosteroids.


Lifelong dietary protein restriction accelerates skeletal muscle loss and reduces muscle fibre size by impairing proteostasis and mitochondrial homeostasis.
The early life environment significantly affects the development of age-related skeletal muscle disorders. However, the long-term effects of lactational protein restriction on skeletal muscle are still poorly defined. Our study revealed that male mice nursed by dams fed a low-protein diet during lactation exhibited skeletal muscle growth restriction. This was associated with a dysregulation in the expression levels of genes related to the ribosome, mitochondria and skeletal muscle development. We reported that lifelong protein restriction accelerated loss of type-IIa muscle fibres and reduced muscle fibre size by impairing mitochondrial homeostasis and proteostasis at 18 months of age. However, feeding a normal-protein diet following lactational protein restriction prevented accelerated fibre loss and fibre size reduction in later life. These findings provide novel insight into the mechanisms by which lactational protein restriction hinders skeletal muscle growth and includes evidence that lifelong dietary protein restriction accelerated skeletal muscle loss in later life.


Degradable hyaluronic acid/chitosan polyelectrolyte multilayers with marine fouling-release properties.
Polysaccharide multilayers consisting of hyaluronic acid and chitosan were prepared by layer-by-layer assembly. To be used in seawater, the multilayers were crosslinked to a different degree using thermal or chemical methods. ATR-FTIR revealed different amide densities as a result of the crosslinking conditions. AFM showed that the crosslinking affected the roughness and swelling behavior of the coatings. The stability and degradability of the multilayers in aqueous environments were monitored with spectroscopic ellipsometry. The resistance of the coatings against non-specific protein adsorption was characterized by SPR spectroscopy. Settlement assays using Ulva linza zoospores and removal assays using the diatom Navicula incerta showed that the slowly degradable coatings were less prone to fouling than the strongly crosslinked ones. Thus, the coatings were a suitable model system to show that crosslinking the multilayers under mild conditions and equipping the coatings with controlled degradation rates enhances their antifouling and fouling-release properties against marine fouling organisms.


The therapeutic effects of epidural intercellular adhesion molecule-1 monoclonal antibody in a rabbit model: involvement of the intercellular adhesion molecule-1 pathway in spinal cord ischemia.
The pathophysiology of ischemia/reperfusion injury involves extravascular migration of leukocytes from the bloodstream to the site of injury. Leukocyte adhesion and intercellular adhesion molecule-1 (ICAM-1) play an important role in the recruitment of leukocytes to the site of injury. In this study, we evaluated the role of the ICAM-1 in spinal cord ischemia and the therapeutic effects of epidural ICAM-1 monoclonal antibody (Mab). The descending aorta was occluded below the renal artery with an aneurysm clip in rabbits anesthetized with halothane. The following variables were evaluated, in addition to ICAM-1 expression in the lumbar spinal cord, in animals receiving saline or ICAM-1 Mab via the epidural route: (1) leukocyte recruitment in the lumen of capillary vessels of the lumbar spinal cord (L6-7) at 8 h after 30 min of aortic occlusion and (2) neurological evaluation at 20 h after aortic occlusion of 10, 15, 17.5, 20, or 25 min. Paraplegia was graded with the following scale: Grade 0, no deficit; Grade 1, partial deficit; and Grade 2, complete paraplegia. Spinal cord ischemia increased the expression of ICAM-1 in the endothelium of spinal cord capillaries and led to capillary leukocyte recruitment and extravascular migration into the lumbar spinal cord parenchyma, which was ablated with epidural ICAM-1 Mab. Epidural ICAM-1 Mab reduced neurological deficits and offered neuroprotection. These findings demonstrate the involvement of the ICAM-1 pathway in spinal cord ischemia and the neuroprotective effects of epidural ICAM-1 Mab. Strategies to ameliorate spinal cord ischemia may entail the administration of leukocyte antiadhesion molecules into the neuraxial space.


Sleeve gastrectomy and Roux-en-Y gastric bypass alter the gut-brain communication.
This study investigated the anatomical integrity of vagal innervation of the gastrointestinal tract following vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB) operations. The retrograde tracer fast blue (FB) was injected into the stomach to label vagal neurons originating from nodose ganglion (NG) and dorsal motor nucleus of the vagus (DMV). Microglia activation was determined by quantifying changes in the fluorescent staining of hindbrain sections against an ionizing calcium adapter binding molecule 1 (Iba1). Reorganization of vagal afferents in the hindbrain was studied by fluorescent staining against isolectin 4 (IB4). The density of Iba1- and IB4-immunoreactivity was analyzed using Nikon Elements software. There was no difference in the number of FB-labeled neurons located in NG and DMV between VSG and VSG-sham rats. RYGB, but not RYGB-sham rats, showed a dramatic reduction in number of FB-labeled neurons located in the NG and DMV. VSG increased, while the RYGB operation decreased, the density of vagal afferents in the nucleus tractus solitarius (NTS). The RYGB operation, but not the VSG procedure, significantly activated microglia in the NTS and DMV. Results of this study show that the RYGB, but not the VSG procedure, triggers microglia activation in vagal structures and remodels gut-brain communication.


Comparison of comorbidities of migraine and tension headache in a pediatric headache clinic.
Objective To compare comorbidities between migraine and tension headache in patients treated in a tertiary pediatric headache clinic. Methods Files of patients with migraine or tension headache attending a pediatric headache clinic were retrospectively reviewed for the presence of organic comorbidities. Additionally, patients were screened with the self-report Strengths and Difficulties Questionnaire to identify nonorganic comorbidities. If necessary, patients were referred to a pediatric psychiatrist, psychologist or social worker for further evaluation. Results The study cohort comprised 401 patients: 200 with migraine and 201 with tension headache. The main organic comorbidities were atopic disease, asthma, and first-reported iron-deficiency anemia; all occurred with statistical significance more often with migraine than with tension headache (Familial Mediterranean fever was six times more frequent in the migraine group than in the tension headache group, but the difference was not statistically significant. Nonorganic comorbidities (psychiatric, social stressors) were associated significantly more often with tension headache than with migraine (48.3% versus 33%; p = 0.03). Conclusions Children and adolescents with migraine or tension headache treated in a dedicated clinic have high rates of organic and nonorganic comorbidities. In this setting, patients with migraine have significantly more organic comorbidities, and patients with tension headache, significantly more nonorganic comorbidities.


Network meta-analysis of margin threshold for women with ductal carcinoma in situ.
Negative margins are associated with reduced risk of ipsilateral breast tumor recurrence (IBTR) for women with ductal carcinoma in situ (DCIS) treated with breast-conserving surgery (BCS). However, there is no consensus about the best minimum margin width. We searched the PubMed database for studies of DCIS published in English between January 1970 and July 2010 and examined the relationship between IBTR and margin status after BCS for DCIS. Women with DCIS were stratified into two groups, BCS with or without radiotherapy. We used frequentist and Bayesian approaches to estimate the odds ratios (OR) of IBTR for groups with negative margins and positive margins. We further examined specific margin thresholds using mixed treatment comparisons and meta-regression techniques. All statistical tests were two-sided. We identified 21 studies published in 24 articles. A total of 1066 IBTR events occurred in 7564 patients, including BCS alone (565 IBTR events in 3098 patients) and BCS with radiotherapy (501 IBTR events in 4466 patients). Compared with positive margins, negative margins were associated with reduced risk of IBTR in patients with radiotherapy (OR = 0.46, 95% credible interval [CrI] = 0.35 to 0.59), and in patients without radiotherapy (OR = 0.34, 95% CrI = 0.24 to 0.47). Compared with patients with positive margins, the risk of IBTR for patients with negative margins was smaller (negative margin >0 mm, OR = 0.45, 95% CrI = 0.38 to 0.53; >2 mm, OR = 0.38, 95% CrI = 0.28 to 0.51; >5 mm, OR = 0.55, 95% CrI = 0.15 to 1.30; and >10 mm, OR = 0.17, 95% CrI = 0.12 to 0.24). Compared with a negative margin greater than 2 mm, a negative margin of at least 10 mm was associated with a lower risk of IBTR (OR = 0.46, 95% CrI = 0.29 to 0.69). We found a probability of .96 that a negative margin threshold greater than 10 mm is the best option compared with other margin thresholds. Negative surgical margins should be obtained for DCIS patients after BCS regardless of radiotherapy. Within cosmetic constraint, surgeons should attempt to achieve negative margins as wide as possible in their first attempt. More studies are needed to understand whether margin thresholds greater than 10 mm are warranted.


Epidermal growth factor enhances expression of connexin 43 protein in cultured porcine preantral follicles.
Connexin 43 (Cx43) and gap junctional coupling appear to play a critical role in early follicular development because absence of Cx43 disrupts progression of follicles beyond primary stages in transgenic mouse ovaries. Two experimental culture systems were used to determine whether epidermal growth factor (EGF) stimulates expression of Cx43 in early porcine follicular development. Ovarian explants were collected from 32- to 40-day-old gilts and cultured for 6 days on membrane inserts in Waymouth MB 752/1 medium supplemented with 0, 50, or 500 ng/ml mouse EGF. Western blot analysis demonstrated significant increases (P < 0.05) in relative amounts of Cx43 protein (both phosphorylated and nonphosphorylated) with 50 and 500 ng/ml of EGF as compared with control cultures. Preantral follicles were enzymatically isolated from 70- to 86-day-old gilts and cultured for 8 days in collagen matrices. Medium and EGF treatments were the same as previously described. Western blot analysis demonstrated a significant increase (P < 0.05) in relative amounts of Cx43 protein with 50 and 500 ng/ml of EGF as compared with control cultures. EGF increased expression of Cx43 protein in secondary preantral follicles in a dose-dependent manner, which suggests that EGF or similar growth factor molecules may modulate early folliculogenesis by stimulating expression of Cx43 gap junctions.


Current understanding of psycho-neurobiology in depressive disorders with suicidal thoughts - translational models.
Epidemiological data confirm the rising incidence of depression associated with suicidal ideation and cardiovascular comorbidities of coronary type. In contradiction with the large number of antidepressant drugs, the therapeutic results are not satisfactory, with numerous existing incomplete remissions characterized by maintained cellular dysfunctionalities that amplify the cognitive deterioration and the risk of several somatic comorbidities. The surprising fact is the relatively high number of deaths in this type of patients due to acute coronary disease (myocardial infarction - MI). The vulnerability of hippocampal and frontal cortex cerebral structures is presented as obtained on animal model consecutive to hypothalamic-pituitary-adrenal (HPA) axis hyperactivity and on theoretical model where the hypothalamic disconnectivity determines the activation in the sympathetic autonomic nervous system, leading to heart disorders: high blood pressure, left ventricular hypertrophy and coronary illness. Identifying the association of psychological risk factors, patients fitting in a model of psychosomatic dominant personality traits, where the main risk factors are represented by inflexibility, guilt and self-accusation feelings, associated with increase of biological indicators (proinflammatory factors, endothelial dysfunction and cytokine aggressiveness) and neuroimaging indicators (frontal, temporal, hippocampal atrophy, ventriculomegaly, cerebellum atrophy). Changes identified post-mortem in the arterioles from the frontal cortex were found also in the coronary vessels, suggesting a symmetric evolution The highlighted personality factors are responsible for the decrease of adherence and compliance both in the psychiatric and the cardiologic treatment, the patient being exposed to behavioral risks regarding life style and nutrition, factors that increase the risk for acute coronary accident. The psycho-neurobiological inspired theoretical models argument the importance of a differentiated and customized approach of the patients with depressive disorder and suicidal ideation, and they can be the base for initiating strategies for prevention of unfavorable evolution and risk of death by MI.


[Long-term results of combined laryngeal resections in stage III-IV cancer using endoprostheses made of different polymeric materials].
The analysis of effectiveness of combined vertical and horizontal laryngeal resections with application of endoprostheses for cancer stage III-IV has shown that the biocompatible polymeric endoprostheses based on vinylpyrrolidone and alkyl methacrylate are superior to endoprostheses made of medical silicone by frequency of operative wound healing by first intention, by feasibility of tracheostoma one-stage permanent suturing at operation and early decannulation, by the degree of correction of external respiration dysfunction and blood gas composition. Long-term therapeutic results of application of biocompatible polymeric endoprosthesis are similar to those in using endoprosthesis made of biologically intact material--medical silicone.


Survey of management practices related to bovine respiratory disease in preweaned calves on California dairies.
In the spring of 2013, a survey of California (CA) dairies was performed to characterize management practices related to bovine respiratory disease in preweaned calves, compare these practices across geographic regions of the state, and determine the principal components that explain the variability in management between herds. The questionnaire consisted of 53 questions divided into 6 sections to assess management practices affecting dairy calves from precalving to weaning. The questionnaire was mailed to 1,523 grade A licensed dairies in CA and 224 responses (14.7%) were collected. Survey response rates were similar over the 3 defined regions of CA: northern CA, northern San Joaquin Valley, and the greater southern CA region. The mean size of respondent herds was 1,423 milking cows. Most dairies reported raising preweaned calves on-site (59.7%). In 93.3% of dairies, preweaned calves were raised in some form of individual housing. Nonsaleable milk was the most frequent liquid diet fed to preweaned heifers (75.2%). Several important differences were identified between calf-raising practices in CA and practices reported in recent nationwide studies, including herd sizes, housing practices, and sources of milk fed to heifers. The differences between the CA and nationwide studies may be explained by differences in herd size. Regional differences within CA were also identified. Compared with the 2 other regions, northern CA dairies were found to have smaller herds, less Holstein cattle, calves remained with dams for longer periods of time after calving, were more likely to be certified organic dairies, and raised their own calves more often. Principal component analysis was performed and identified 11 components composed of 28 variables (questions) that explained 66.5% of the variability in the data. The identified components and questions will contribute to developing a risk assessment tool for bovine respiratory disease in preweaned dairy calves.


Amiodarone versus sotalol for atrial fibrillation.
The optimal pharmacologic means to restore and maintain sinus rhythm in patients with atrial fibrillation remains controversial. In this double-blind, placebo-controlled trial, we randomly assigned 665 patients who were receiving anticoagulants and had persistent atrial fibrillation to receive amiodarone (267 patients), sotalol (261 patients), or placebo (137 patients) and monitored them for 1 to 4.5 years. The primary end point was the time to recurrence of atrial fibrillation beginning on day 28, determined by means of weekly transtelephonic monitoring. Spontaneous conversion occurred in 27.1 percent of the amiodarone group, 24.2 percent of the sotalol group, and 0.8 percent of the placebo group, and direct-current cardioversion failed in 27.7 percent, 26.5 percent, and 32.1 percent, respectively. The median times to a recurrence of atrial fibrillation were 487 days in the amiodarone group, 74 days in the sotalol group, and 6 days in the placebo group according to intention to treat and 809, 209, and 13 days, respectively, according to treatment received. Amiodarone was superior to sotalol (P<0.001) and to placebo (P<0.001), and sotalol was superior to placebo (P<0.001). In patients with ischemic heart disease, the median time to a recurrence of atrial fibrillation was 569 days with amiodarone therapy and 428 days with sotalol therapy (P=0.53). Restoration and maintenance of sinus rhythm significantly improved the quality of life and exercise capacity. There were no significant differences in major adverse events among the three groups. Amiodarone and sotalol are equally efficacious in converting atrial fibrillation to sinus rhythm. Amiodarone is superior for maintaining sinus rhythm, but both drugs have similar efficacy in patients with ischemic heart disease. Sustained sinus rhythm is associated with an improved quality of life and improved exercise performance.


Antisecretory and gastroprotective activities of compounds endowed with H2 antagonistic and nitric oxide (NO) donor properties.
In spite of the well recognized gastric antisecretory activity, the gastroprotective potential of histamine H2 receptor antagonists is controversial. Most clinical studies in fact indicate that these drugs do not substantially protect the gastric mucosa from aggressive factors. Nitric oxide (NO) has been recently recognized as a fundamental mediator in gastric defence mechanisms, due to its ability to increase gastric mucosal blood flow and mucus production and to inhibit neutrophils adherence to endothelial cells. The aim of this study was to investigate the gastroprotective and H2 receptor antagonistic activity of a series of lamtidine analogues which contain different NO-releasing moieties (furoxan, nitroxy and nitrosothiol). These compounds were tested, in comparison with related H2 antagonists devoid of NO-donor structures, in different H2 receptor assays and in the conscious rat against 0.6 N HCl-induced gastric lesions. All the compounds tested were able to antagonize histamine-mediated responses at cardiac and gastric H2 receptors; however, furoxan and nitroxy derivatives were 10-fold less potent than the analogues devoid of NO-donor properties. By contrast, NO-donor compounds were more active than reference H2 antagonists as gastroprotective agents against mucosal injury induced by 0.6 N HCl. Among the different NO-donor moieties, the furoxan group conferred to the H2 antagonist molecule the highest gastroprotective potential; this finding closely correlates with the characteristics of NO release. In conclusions, lamtidine-analogue H2 antagonists combined with NO-donor moieties are endowed with gastric antisecretory and protective activity and could be the prototypes of a new class of anti-ulcer drugs. Finally, the furoxan NO donor group seems to be the most favourable among the different moieties tested.


Concerted feedback inhibition of the aspartokinase of Rhodospirillum tenue by threonine and methionine: a novel pattern.
The presence of a single aspartokinase was demonstrated in Rhodospirillum tenue. The enzyme has been purified about 60-fold. No physical association exists in this species between aspartokinase and homoserine dehydrogenase. The general properties of the enzyme are described. Inhibition by l-lysine, by l-threonine, and concerted inhibition by these two end products are regulatory characters which have also been found in many other species. In R. tenue, aspartokinase is also subject to a hitherto not encountered type of concerted feedback inhibition, by l-threonine plus l-methionine. The inhibition caused by lysine can be reversed either by glycine, l-isoleucine, l-methionine, or l-phenylalanine. The concerted inhibition by lysine plus threonine is reversed by glycine, l-isoleucine, or l-phenylalanine, but not by l-methionine, which exerts in conjunction with threonine the independent concerted inhibition referred to above. Addition of single or several metabolites to cultures of R. tenue caused inhibition of growth and reversal of growth inhibition, compatible with the effects observed in vitro on aspartokinase activity. The regulation of this enzyme in relation to that of other bacterial aspartokinases is discussed.


Genetic identification of a respiratory arsenate reductase.
For more than a decade, it has been recognized that arsenate [H2AsO41-; As(V)] can be used by microorganisms as a terminal electron acceptor in anaerobic respiration. Given the toxicity of arsenic, the mechanistic basis of this process is intriguing, as is its evolutionary origin. Here we show that a two-gene cluster (arrAB; arsenate respiratory reduction) in the bacterium Shewanella sp. strain ANA-3 specifically confers respiratory As(V) reductase activity. Mutants with in-frame deletions of either arrA or arrB are incapable of growing on As(V), yet both are able to grow on a wide variety of other electron acceptors as efficiently as the wild-type. Complementation by the wild-type sequence rescues the mutants' ability to respire As(V). arrA is predicted to encode a 95.2-kDa protein with sequence motifs similar to the molybdenum containing enzymes of the dimethyl sulfoxide reductase family. arrB is predicted to encode a 25.7-kDa iron-sulfur protein. arrA and arrB comprise an operon that contains a twin arginine translocation (Tat) motif in ArrA (but not in ArrB) as well as a putative anaerobic transcription factor binding site upstream of arrA, suggesting that the respiratory As(V) reductase is exported to the periplasm via the Tat pathway and under anaerobic transcriptional control. These genes appear to define a new class of reductases that are specific for respiratory As(V) reduction.


Evaluation of Machine Learning Approaches for Predicting Warfarin Discharge Dose in Cardiac Surgery Patients: Retrospective Algorithm Development and Validation Study.
Warfarin dosing in cardiac surgery patients is complicated by a heightened sensitivity to the drug, predisposing patients to adverse events. Predictive algorithms are therefore needed to guide warfarin dosing in cardiac surgery patients. This study aimed to develop and validate an algorithm for predicting the warfarin dose needed to attain a therapeutic international normalized ratio (INR) at the time of discharge in cardiac surgery patients. We abstracted variables influencing warfarin dosage from the records of 1031 encounters initiating warfarin between April 1, 2011, and November 29, 2019, at St Michael's Hospital in Toronto, Ontario, Canada. We compared the performance of penalized linear regression, k-nearest neighbors, random forest regression, gradient boosting, multivariate adaptive regression splines, and an ensemble model combining the predictions of the 5 regression models. We developed and validated separate models for predicting the warfarin dose required for achieving a discharge INR of 2.0-3.0 in patients undergoing all forms of cardiac surgery except mechanical mitral valve replacement and a discharge INR of 2.5-3.5 in patients receiving a mechanical mitral valve replacement. For the former, we selected 80% of encounters (n=780) who had initiated warfarin during their hospital admission and had achieved a target INR of 2.0-3.0 at the time of discharge as the training cohort. Following 10-fold cross-validation, model accuracy was evaluated in a test cohort comprised solely of cardiac surgery patients. For patients requiring a target INR of 2.5-3.5 (n=165), we used leave-p-out cross-validation (p=3 observations) to estimate model performance. For each approach, we determined the mean absolute error (MAE) and the proportion of predictions within 20% of the true warfarin dose. We retrospectively evaluated the best-performing algorithm in clinical practice by comparing the proportion of cardiovascular surgery patients discharged with a therapeutic INR before (April 2011 and July 2019) and following (September 2021 and May 2, 2022) its implementation in routine care. Random forest regression was the best-performing model for patients with a target INR of 2.0-3.0, an MAE of 1.13 mg, and 39.5% of predictions of falling within 20% of the actual therapeutic discharge dose. For patients with a target INR of 2.5-3.5, the ensemble model performed best, with an MAE of 1.11 mg and 43.6% of predictions being within 20% of the actual therapeutic discharge dose. The proportion of cardiovascular surgery patients discharged with a therapeutic INR before and following implementation of these algorithms in clinical practice was 47.5% (305/641) and 61.1% (11/18), respectively. Machine learning algorithms based on routinely available clinical data can help guide initial warfarin dosing in cardiac surgery patients and optimize the postsurgical anticoagulation of these patients.


Cellulose: from biocompatible to bioactive material.
Since the papyri, cellulose has played a significant role in human culture, especially as paper. Nowadays, this ancient product has found new scientific applications in the expanding sector of paper-based technology. Among paper-based devices, paper-based biosensors raise a special interest. The high selectivity of biomolecules for target analytes makes these sensors efficient. Moreover, simple paper-based detection devices do not require hardware or specific technical skill. They are inexpensive, rapid, user-friendly and therefore highly promising for providing resource-limited settings with point-of-care diagnostics. The immobilization of biomolecules onto cellulose is a key step in the development of these sensing devices. Following an overview of cellulose structural features and physicochemical properties, this article reviews current techniques for the immobilization of biomolecules on paper membranes. These procedures are categorized into physical, biological and chemical approaches. There is no universal method for biomolecule immobilization. Thus, for a given paper-based biochip, each strategy can be considered.


Nicotinic modulation of network and synaptic transmission in the immature hippocampus investigated with genetically modified mice.
The hippocampus, a key structure in learning and memory processes, receives a powerful cholinergic innervation from the septum and contains nicotinic acetylcholine receptors (nAChRs). Early in postnatal development, activation of nAChRs by nicotine or endogenous acetylcholine contributes to enhance synaptic signalling. Here, the patch-clamp technique was used to assess the contribution of alpha7 and beta2-containing (alpha7* and beta2*) nAChRs to nicotine-elicited modulation of GABAergic and glutamatergic activity at the network and single-cell level in the immature hippocampus of wild-type (WT), alpha7-/- and beta2-/- mice. We found that alpha7* and beta2* nAChRs were sufficient to modulate nicotine-induced increase in frequency of spontaneously occurring giant depolarizing potentials (GDPs), which are generated at the network level by the synergistic action of glutamate and depolarizing GABA, and thought to play a crucial role in neuronal wiring. However, alpha7* but not beta2* receptors were essential in nicotine-induced increase of interictal discharge frequency recorded after postnatal day 3 in the presence of bicuculline, when GABA shifted from the depolarizing to the hyperpolarizing direction. To correlate these observations with nicotine-elicited changes in synaptic transmission, we recorded spontaneous GABAergic and glutamatergic postsynaptic currents in pyramidal cells and interneurons localized in stratum oriens, stratum pyramidale and stratum radiatum, in slices obtained from WT and knock-out animals. We found that early in postnatal life alpha7* and beta2* nAChRs exert a fine regional modulation of GABAergic and glutamatergic transmission that underlies nicotine-elicited changes in network synchronization.