Integrin-αvβ3 is a Therapeutically Targetable Fundamental Factor in Medulloblastoma Tumorigenicity and Radioresistance.
Medulloblastoma is one of the most prevalent solid tumors found in children, occurring in the brain's posterior fossa. The standard treatment protocol involves maximal resection surgery followed by craniospinal irradiation and chemotherapy. Despite a long-term survival rate of 70%, wide disparities among patients have been observed. The identification of pertinent targets for both initial and recurrent medulloblastoma cases is imperative. Both primary and recurrent medulloblastoma are marked by their aggressive infiltration into surrounding brain tissue, robust angiogenesis, and resistance to radiotherapy. While the significant role of integrin-αvβ3 in driving these characteristics has been extensively documented in glioblastoma, its impact in the context of medulloblastoma remains largely unexplored. Integrin-αvβ3 was found to be expressed in a subset of patients with medulloblastoma. We investigated the role of integrin-αvβ3 using medulloblastoma-derived cell lines with β3-subunit depletion or overexpression both in vitro and in vivo settings. By generating radioresistant medulloblastoma cell lines, we uncovered an increased integrin-αvβ3 expression, which correlated with increased susceptibility to pharmacologic integrin-αvβ3 inhibition with cilengitide, a competitive ligand mimetic. Finally, we conducted single-photon emission computed tomography (SPECT)/MRI studies on orthotopic models using a radiolabeled integrin-αvβ3 ligand (99mTc-RAFT-RGD). This innovative approach presents the potential for a novel predictive imaging technique in the realm of medulloblastoma. Altogether, our findings lay the foundation for employing SPECT/MRI to identify a specific subset of patients with medulloblastoma eligible for integrin-αvβ3-directed therapies. This breakthrough offers a pathway toward more targeted and effective interventions in the treatment of medulloblastoma. This study demonstrates integrin-αvβ3's fundamental role in medulloblastoma tumorigenicity and radioresistance and the effect of its expression on cilengitide functional activity.


[Buccoepithelial cytologic lesions in workers exposed to chemical products].
Our aim was to describe the genetic and cytologic lesions induced by occupational exposition to chemicals (barley powder, carbon dioxide, ammonia, organic solvents, and welding vapors) and to correlate frequencies of appearance of buccoepithelial cytologic disorders with age and toxic habits. This descriptive, transverse observational study was comprised of 77 male workers to obtain information concerning age, on-the-job seniority, time of exposure, direct and indirect exposure, use of breathing protection, and toxic habits. We used exfoliated cells of the buccal mucosa to estimate presence of chromosomal aberrations (micronuclei) and nuclear abnormalities (binucleation, pyknosis, condensed chromatin, and karyolysis). Results were correlated by Pearson's coefficient. The investigated workers labored 8 h/ day; 80.5% were exposed directly to chemicals, while 19.5% were indirectly exposed during an average of 6.5 h per workday. A total of 85.7% of workers referred not using breathing protection, and 28.6% and 36.4% reported smoking and alcohol consumption, respectively. In a general manner, we detected a certain prevalence of irreversible cytotoxic lesions and absence of a statistically significant correlation between cytotoxicity and age (r = 0.14), alcohol consumption (r = 0.02) and smoking (r = 0.11).


Effect of Fluorescent Proteins on Fusion Partners Using Polyglutamine Toxicity Assays in Yeast.
For the investigation of protein localization and trafficking using live cell imaging, researchers often rely on fusing their protein of interest to a fluorescent reporter. The constantly evolving list of genetically encoded fluorescent proteins (FPs) presents users with several alternatives when it comes to fluorescent fusion design. Each FP has specific optical and biophysical properties that can affect the biochemical, cellular, and functional properties of the resulting fluorescent fusions. For instance, several FPs tend to form nonspecific oligomers that are susceptible to impede on the function of the fusion partner. Unfortunately, only a few methods exist to test the impact of FPs on the behavior of the fluorescent reporter. Here, we describe a simple method that enables the rapid assessment of the impact of FPs using polyglutamine (polyQ) toxicity assays in the budding yeast Saccharomyces cerevisiae. PolyQ-expanded huntingtin proteins are associated with the onset of Huntington's disease (HD), where the expanded huntingtin aggregates into toxic oligomers and inclusion bodies. The aggregation and toxicity of polyQ expansions in yeast are highly dependent on the sequences flanking the polyQ region, including the presence of fluorescent tags, thus providing an ideal experimental platform to study the impact of FPs on the behavior of their fusion partner.


Prescription Pattern of Drugs Used for Neuropathic Pain and Adherence to NeuPSIG Guidelines in Cancer.
The objective of the present research was to evaluate the prescription pattern of the drugs used in the pharmacological treatment of cancer-related neuropathic pain (CRNP) and to assess the adherence of the physicians to the Neuropathic Pain Special Interest Group (NeuPSIG) Guidelines. This was a cross-sectional, observational study where patients who presented to the pain and palliative care outpatient clinic of the tertiary care hospital with CRNP were prospectively recruited. Participants were screened for neuropathic pain using DN4 questionnaire. Demographic details, diagnosis, medication details, and adherence to NeuPSIG guidelines were assessed using a validated questionnaire. Of 300 patients screened, 64% were male and 36% were female, with a mean age of 48.26 ± 13.05 years. The predominant symptoms found were pin-and-needle sensation (99%) followed by tingling sensation (98.66%). The most common diagnosis was head-and-neck cancers (37.3%) followed by bone cancers (17.3%) and lung cancers (15.3%). Among the first-line drugs recommended in NeuPSIG for CRNP, pregabalin (78.7%) was the most common drug prescribed followed by amitriptyline (67%). The most common co-prescribed drugs were acid suppressants drugs (50.7%). Tapentadol, which is not part of the NeuPSIG guidelines, was prescribed on 51 occasions for neuropathic pain. Underdosing was observed in 272 prescriptions. Only 12 prescriptions completely adhered, while 275 had partial, and 13 prescriptions had poor adherence to NeuPSIG guidelines. The most commonly used drugs in the treatment of CRNP were pregabalin and amitriptyline. Most physician partially or did not adhere to the NeuPSIG guideline in the management of CRNP.


Co-expression of a trans-dominant negative mutant of the human immunodeficiency virus type 1 (HIV-1) Rev protein affects the Rev-dependent splicing pattern and expression of HIV-1 RNAs.
Trans-dominant negative mutants of the human immunodeficiency virus type 1 (HIV-1) regulatory protein Rev inhibit the function of wild-type Rev in a dose-dependent manner. This was previously shown to be caused by nuclear retention of the wild-type protein. In the present work, further analysis of the trans-dominant negative effect was performed using cotransfection experiments with different constructs encoding HIV-1 Rev and viral structural proteins together with a plasmid encoding a trans-dominant negative Rev mutant. Thus, one species of pre-mRNA was transcribed from the reporter plasmids. This pre-mRNA was then either spliced or exported by Rev as unspliced RNA for translation of the HIV structural proteins. An immunofluorescence assay and Western blot analysis were used for analysis of protein expression. In situ hybridization was applied for labelling of unspliced mRNA in transfected cells, and RNase protection analysis was used to determine the relative amount of unspliced versus spliced mRNAs. The experiments confirmed that the transdominant negative mutant inhibited nuclear export of unspliced mRNA. It was, in addition, demonstrated for the first time that the trans-dominant negative mutant also affected a Rev-dependent regulatory step connected with viral pre-mRNA splicing. As a consequence, proteins expressed from unspliced and singly spliced HIV mRNAs decreased while there was an increase in protein products encoded by spliced and alternatively spliced mRNAs.


Multilocus sequence analysis for assessment of the biogeography and evolutionary genetics of four Bradyrhizobium species that nodulate soybeans on the asiatic continent.
A highly supported maximum-likelihood species phylogeny for the genus Bradyrhizobium was inferred from a supermatrix obtained from the concatenation of partial atpD, recA, glnII, and rpoB sequences corresponding to 33 reference strains and 76 bradyrhizobia isolated from the nodules of Glycine max (soybean) trap plants inoculated with soil samples from Myanmar, India, Nepal, and Vietnam. The power of the multigene approach using multiple strains per species was evaluated in terms of overall tree resolution and phylogenetic congruence, representing a practical and portable option for bacterial molecular systematics. Potential pitfalls of the approach are highlighted. Seventy-five of the isolates could be classified as B. japonicum type Ia (USDA110/USDA122-like), B. liaoningense, B. yuanmingense, or B. elkanii, whereas one represented a novel Bradyrhizobium lineage. Most Nepalese B. japonicum Ia isolates belong to a highly epidemic clone closely related to strain USDA110. Significant phylogenetic evidence against the monophyly of the of B. japonicum I and Ia lineages was found. Analysis of their DNA polymorphisms revealed high population distances, significant genetic differentiation, and contrasting population genetic structures, suggesting that the strains in the Ia lineage are misclassified as B. japonicum. The DNA polymorphism patterns of all species conformed to the expectations of the neutral mutation and population equilibrium models and, excluding the B. japonicum Ia lineage, were consistent with intermediate recombination levels. All species displayed epidemic clones and had broad geographic and environmental distribution ranges, as revealed by mapping climate types and geographic origins of the isolates on the species tree.


Breakfast frequency, adiposity, and cardiovascular risk factors as markers in adolescents.
To analyse the relationship between skipping breakfast and haemodynamic, metabolic, inflammatory, and cardiovascular risk factors in adolescents. A cross-sectional study was carried out with information from an ongoing cohort study in Presidente Prudente, São Paulo, Brazil. The sample comprised of 120 adolescents (11.7±0.8 years old) who met the following inclusion criteria: age between 11 and 14 years; enrolled in the school unit of elementary education; absence of any known disease; and no drug consumption. The parents or legal guardians of the patients signed a formal informed consent. Skipping breakfast was self-reported through face-to-face interviews. Blood pressure, intima-media thickness, trunk fatness, total and fractional cholesterol levels - high-density lipoprotein cholesterol and low-density lipoprotein cholesterol - triacylglycerol levels, and high-sensitivity C-reactive protein levels were measured. In this study, 47.5% (95% CI: 38.5-56.4%) of the adolescents reported skipping breakfast at least 1 day/week. Adolescents who skipped breakfast had higher values of trunk fatness and systolic blood pressure. Breakfast frequency was negatively related to systolic blood pressure (β -1.99 [-3.67; -0.31]) and z score dyslipidaemia (β -0.46 [-0.90; -0.01]), but this relationship was mediated by trunk fatness. Skipping breakfast is related to cardiovascular risk factors in adolescents, and this relationship was mainly mediated by trunk fatness.


The impact of procedural activities on musculoskeletal pain experienced by pregnant surgeons.
Two-thirds of surgeons report work-related musculoskeletal disorders (WRMD). There is limited data on WRMD symptoms experienced by pregnant surgeons. We distributed an electronic survey via personal contacts to attending and trainee surgeons across six academic institutions to assess the impact of procedural activities and surgical ergonomics (SE) on WRMD symptoms during pregnancy. Fifty-three respondents were currently or had been pregnant while clinically active, representing 93 total pregnancies. 94.7% reported that symptoms were exacerbated by workplace activities during pregnancy and 13.2% took unplanned time off work as a result. Beyond 24 weeks of pregnancy, 89.2% of respondents continued to operate/perform procedures, 81.7% worked >24-h shifts and 69.9% performed repetitive lifting >50 pounds. No respondents were aware of any institutional pregnancy-specific SE policies. Procedural activities can exacerbate pain symptoms for the pregnant surgeon. SE best practices during pregnancy warrant further attention.


Molecular point-of-care devices for the diagnosis of infectious diseases in resource-limited settings - A review of the current landscape, technical challenges, and clinical impact.
Molecular point-of-care (POC) tests offer high sensitivity, rapid turnaround times, relative ease of use, and the convenience of laboratory-grade testing in the absence of formal laboratory spaces and equipment, making them appealing options for infectious disease diagnosis in resource-limited settings. In this review, we discuss the role and potential of molecular POC tests in resource-limited settings and their associated logistical challenges. We discuss U.S. Food and Drug Administration approval, Clinical Laboratory Improvement Amendments complexity levels, and the REASSURED criteria as a starting point for assessing options currently available inside and outside of the United States. We then present POC tests currently in research and development phases that have potential for commercialization and implementation in limited-resource settings. Finally, we review published studies that have assessed the clinical impact of molecular POC testing in limited- and moderate-resource settings.


Palladium(0)-catalyzed dearomative arylation of indoles: convenient access to spiroindolenine derivatives.
Dearomatization of an indole via palladium(0)-catalyzed cross-coupling reaction has been realized. With readily available triphenylphosphine as ligand, various spiroindolenine derivatives have been obtained in good to excellent yields, and enantioselective control is also feasible with chiral ligands.


Maternal exercise during pregnancy affects mitochondrial enzymatic activity and biogenesis in offspring brain.
The present study addresses whether exercise during pregnancy in mouse alters mitochondrial function in the brains of the resultant offspring. We divided pregnant mice into four groups: a control group and groups of mice that exercised for 20 (E20m), 30 (E30m) and 40 min/d (E40m). The pregnant mice ran on a treadmill at 12 m/min, 5 d/week for a duration of 3 weeks. The protein expression of cytochrome c oxidase subunit Va (CVa) was downregulated in the offspring of the E20m group, unlike that in the control animals, whereas CVa expression was reserved in the E40m neonates. The F1-ATPase catalytic core (Core) protein expression levels were the highest in the E40m group neonates. Complex I, IV and ATPase activities were significantly lower in the E20m group than that in the control group neonates and were reserved in the E30m and E40m group neonates. The activities of citrate synthase and pyruvate dehydrogenase were consistent with those of complex I, IV and ATPase. Peroxisome proliferator-activated receptor-gamma coactivator 1-alpha, mitochondrial transcription factor A, nuclear respiratory factor-1 and mitochondrial DNA showed high levels of expression in the E40m neonates compared with the other groups. Malondialdehyde (MDA) levels in E40m neonates were higher than that in the controls but were lower than that in the E20m neonates. Finally, 40 min/d of maternal exercise improved mitochondrial function in the resultant pups and was concomitant with brain-derived trophic factor induction in the hippocampus, thereby functionally improving short-term memory.


A pilot study on the screening of primary hepatocellular carcinoma in selected high risk groups in the population using multiple tumour markers.
A prospective one year study on groups of 377 high risk individuals was done using alphafoetoprotein (AFP), alpha 1antitrypsin (A1AT), alpha 1-acidglycoprotein 1 (A1GP), gammaglutamyltraspeptidase (GGT) and isocitrate dehydrogenase (ICD) to detect hepatocellular carcinoma (HCC). The high risk groups screened were: cirrhosis, unexplanable hepatomegalies, chronic hepatitis B surface antigen (HBsAg) carrier, family members of afflicted HCC cases, individuals on hormonal therapy and males over the age of 30 years. 58/377 (15%) were found to have HCC. This consisted of 16/43 (37%) clinical cirrhosis, 40/71 (56%) unexplanable hepatomegalies, 1/33 (3%) chronic HBsAg, 1/156 (0.6%) family members. AFP remained the most useful test but the others such as A1AT, A1Gp, GGT and ICD recognised both malignant and asymptomatic nonmalignant diseases. Only 4 (7%) patients had resectible tumours detected and 1 patient was found to have liver dysplasia. HBsAg positivity and persistently raised AFP. The significance of HBsAg amongst family members and other group is discussed in terms of genetic susceptibility, environmental oncogenic vulnerability and ultimate screening.


The Total Artificial Heart and the Dilemma of Deactivation.
It is widely believed to be permissible for a physician to discontinue any treatment upon the request of a competent patient. Many also believe it is never permissible for a physician to intentionally kill a patient. I argue that the prospect of deactivating a patient's artificial heart presents us with a dilemma: either the first belief just mentioned is false or the second one is. Whichever horn of the dilemma we choose has significant implications for contemporary medical ethics.


Pulmonary Mycobacterium fortuitum infection with cervical lymphadenitis in a patient carrying autoantibodies to interferon-γ.
A 74-year-old woman was referred to our hospital for an evaluation of unidentified pneumonia. She gradually developed a high-grade fever with a growing infiltrative shadow on chest CT and an enlarging bilateral cervical mass. She was diagnosed with a pulmonary Mycobacterium fortuitum (M. fortuitum) infection with cervical lymphadenitis based on the results of an open biopsy of the cervical lymph node. While the patient's clinical condition resolved almost completely after treatment with multiple antibiotics, neutralizing autoantibodies to interferon-gamma (IFN-γ) were identified in her serum. The progression of disseminated M. fortuitum infection in immunocompetent patients may be affected by the presence of autoantibodies to IFN-γ.


Modulation of the neurotransmitter release in rat cerebellar neurons by GRO beta.
We report here that, in cultured cerebellar granule cells, the CXC chemokine GRObeta stimulates the signaling pathway of the extracellular signal-regulated kinases, and enhances both evoked and spontaneous postsynaptic currents in patch clamped Purkinje neurons from rat cerebellar slices. The GRObeta-induced enhancement of the excitatory post-synaptic currents evoked by stimulating the parallel fibres is blocked by the inhibitor of the extracellular signal-regulated kinases pathway PD98059, which also reduces both basal frequency of spontaneous post-synaptic currents and mean amplitude of evoked excitatory post-synaptic currents. Our results suggest that GRObeta modulates neurotransmitter release in the cerebellum through the activation of the extracellular signal-regulated kinases pathway.


The potential for using administrative and clinical data to analyze outcomes for the cognitively impaired: an assessment of the minimum data set for nursing homes.
Quite frequently, data from administrative or clinical data sets are not considered suitable for research because of concerns about their validity and reliability. The authors discuss the important role that such data sets may play in the future of health care. To provide an indication that all administrative and clinical data bases do not provide inferior data, the authors compare the internal consistency and predictive validity of information from three statewide administrative/clinical databases, focusing on nursing home residents with comparable data from a research database. These databases contain information gathered using the Minimum Data Set (MDS) for Nursing Home Resident Assessment and Care Screening. The two dimensions of status considered in this illustration are cognition and physical function. The results of this comparison indicate that the assessment data in three statewide clinical/administrative databases are as reliable and valid as the data found in the research database. Finally, the authors discuss the precepts one might follow in developing clinical/administrative databases that provide good data. These precepts also can be used as guidelines in the evaluation of the probable usefulness of such databases for assessing outcomes among cognitively impaired nursing home residents.


BF3 x Et2O-mediated cascade cyclizations: synthesis of schweinfurthins F and G.
The total synthesis of the natural stilbene (+)-schweinfurthin G (8) has been accomplished through a sequence based on an efficient cationic cascade cyclization. This cascade process is initiated by Lewis acid promoted ring opening of an epoxide and terminated through a novel reaction with a phenolic oxygen "protected" as its MOM ether. Several Lewis acids have been examined for their ability to induce this new reaction, and BF3 x Et2O was found to be the most effective. The only major byproduct under these conditions was one where the expected secondary alcohol was found as its MOM ether derivative (e.g., 30). While this byproduct could be converted to the original target compound through hydrolysis, it also could be employed as a protected alcohol to allow preparation of a benzylic phosphonate (43) without dehydration of the secondary alcohol. The resulting phosphonate was employed in a Horner-Wadsworth-Emmons condensation with an aldehyde representing the right half of the target compounds, an approach complementary to previous studies based on condensation of a right-half phosphonate and a left-half aldehyde.


Dephosphorylation and activation of exogenous glycogen synthase by adipose-tissue phosphatase.
Exogenous purified rabbit skeletal-muscle glycogen synthase was used as a substrate for adipose-tissue phosphoprotein phosphatase from fed and starved rats in order to (1) compare the relationship between phosphate released from, and the kinetic changes imparted to, the substrate and (2) ascertain if decreases in adipose-tissue phosphatase activity account for the apparent decreased activation of endogenous glycogen synthase from starved as compared with fed rats. Muscle glycogen synthase was phosphorylated with [gamma-(32)P]ATP and cyclic AMP-dependent protein kinase alone, or in combination with a cyclic AMP-independent protein kinase, to 1.7 or 3mol of phosphate per subunit. Adipose-tissue phosphatase activity determined with phosphorylated skeletal-muscle glycogen synthase as substrate was decreased by 35-60% as a consequence of starvation. This decrease in phosphatase activity had little effect on the capacity of adipose-tissue extracts to activate exogenous glycogen synthase (i.e. to increase the glucose 6-phosphate-independent enzyme activity), although there were marked differences in the activation profiles for the two exogenous substrates. Glycogen synthase phosphorylated to 1.7mol of phosphate per subunit was activated rapidly by adipose-tissue extracts from either fed or starved rats, and activation paralleled enzyme dephosphorylation. Glycogen synthase phosphorylated to 3mol of phosphate per subunit was activated more slowly and after a lag period, since release of the first mol of phosphate did not increase the glucose 6-phosphate-independent activity of the enzyme. These patterns of enzyme activation were similar to those observed for the endogenous adipose-tissue glycogen synthase(s): the glucose 6-phosphate-independent activity of the endogenous enzyme from fed rats increased rapidly during incubation, whereas that of starved rats, like that of the more highly phosphorylated muscle enzyme, increased only very slowly after a lag period. The observations made here suggest that (1) changes in glucose 6-phosphate-independent glycogen synthase activity are at best only a qualitative measure of phosphoprotein phosphatase activity and (2) the decrease in glycogen synthase phosphatase activity during starvation is not sufficient to explain the differential glycogen synthase activation in adipose tissue from fed and starved rats. However, alterations in the phosphorylation state of glycogen synthase combined with decreased activity of phosphoprotein phosphatase, both as a consequence of starvation, could explain the apparent markedly decreased enzyme activation.


A comparative study of short chain and long chain mercapto acids used in biosensor fabrication: A VEGF-R1-based immunosensor as a model system.
A novel impedimetric biosensor utilizing a biological receptor, vascular endothelial growth factor receptor-1 (VEGF-R1), was developed for the determination of vascular endothelial growth factor (VEGF). VEGF-R1 was covalently immobilized by coupling with 11-mercaptoundecanoic acid, which formed a self-assembled monolayer on gold electrodes. Cyclic voltammetry and electrochemical impedance spectroscopy techniques were employed to characterize the immobilization process and to detect VEGF. To successfully construct the biosensor current, the experimental parameters were optimized. A Kramers-Kronig transform was performed on the experimental impedance data. The results obtained provided a linear response range from 1 to 6 ng/mL human VEGF. The applicability of the biosensor developed to determine VEGF in a spiked artificial human serum sample was tested. The important parameters related with the biosensors fabricated by using two different mercapto acids were compared in terms of the self-assembly processes, the activation conditions of -COOH ends, linear ranges obtained for VEGF, repeatabilities and reproducibilities, and cleaning procedures. The results of this study revealed that the length of the mercapto acids used for biosensor fabrication considerably affected the analytical performance and the practicability of the preparation of the biosensor.


Anchoring intrinsically disordered proteins to multiple targets: lessons from N-terminus of the p53 protein.
Anchor residues, which are deeply buried upon binding, play an important role in protein-protein interactions by providing recognition specificity and facilitating the binding kinetics. Up to now, studies on anchor residues have been focused mainly on ordered proteins. In this study, we investigated anchor residues in intrinsically disordered proteins (IDPs) which are flexible in the free state. We identified the anchor residues of the N-terminus of the p53 protein (Glu17-Asn29, abbreviated as p53N) which are involved in binding with two different targets (MDM2 and Taz2), and analyzed their side chain conformations in the unbound states. The anchor residues in the unbound p53N were found to frequently sample conformations similar to those observed in the bound complexes (i.e., Phe19, Trp23, and Leu26 in the p53N-MDM2 complex, and Leu22 in the p53N-Taz2 complex). We argue that the bound-like conformations of the anchor residues in the unbound state are important for controlling the specific interactions between IDPs and their targets. Further, we propose a mechanism to account for the binding promiscuity of IDPs in terms of anchor residues and molecular recognition features (MoRFs).


Cobalt-based nanoparticles prepared from MOF-carbon templates as efficient hydrogenation catalysts.
The development of efficient and selective nanostructured catalysts for industrially relevant hydrogenation reactions continues to be an actual goal of chemical research. In particular, the hydrogenation of nitriles and nitroarenes is of importance for the production of primary amines, which constitute essential feedstocks and key intermediates for advanced chemicals, life science molecules and materials. Herein, we report the preparation of graphene shell encapsulated Co3O4- and Co-nanoparticles supported on carbon by the template synthesis of cobalt-terephthalic acid MOF on carbon and subsequent pyrolysis. The resulting nanoparticles create stable and reusable catalysts for selective hydrogenation of functionalized and structurally diverse aromatic, heterocyclic and aliphatic nitriles, and as well as nitro compounds to primary amines (>65 examples). The synthetic and practical utility of this novel non-noble metal-based hydrogenation protocol is demonstrated by upscaling several reactions to multigram-scale and recycling of the catalyst.


Organophosphate nerve agent toxicity in Hydra attenuata.
The toxicity for analogues of sarin (GB), soman (GD), and VX was evaluated using Hydra attenuata as a model organism. The organophosphate nerve agent analogue simulants used in this investigation included the following: isopropyl p-nitrophenyl methylphosphonate (for GB); pinacolyl p-nitrophenyl methylphosphonate (for GD); and diisopropyl S-(2-diisopropylaminoethyl)phosphorothioate, diethyl S-(2-diisopropylaminoethyl)phosphorothioate, and diethyl S-(2-trimethylaminoethyl)phosphorothioate (for VX). The toxicity of each organophosphate nerve agent was assessed quantitatively by measuring the minimal effective concentration within 92 h in H. attenuata. There is a positive correlation between the molecular hydrophobicity of the compound and its ability to cause toxicity. Results from this study indicate the potential for application of this assay in the field of organophosphate chemical warfare agent detection, as well as for the prediction of toxicity of structurally similar organophosphate compounds. The minimal effective concentration for two of the VX analogues was 2 orders of magnitude more toxic than the analogue for GD and 4 orders of magnitude more toxic than the analogue for GB.


Efficacy of a computer based discontinuation strategy to reduce PPI prescriptions: a multicenter cluster-randomized controlled trial.
Deprescribing of inappropriate long-term proton pump inhibitors (PPI) is challenging and there is a lack of useful methods for general practitioners to tackle this. The objective of this randomized controlled trial was to evaluate the effectiveness of the electronic decision aid tool arriba-PPI on reduction of long-term PPI intake. Participants (64.5 ± 12.9 years; 54.4% women) with a PPI intake of at least 6 months were randomized to receive either consultation with arriba-PPI from their general practitioner (n = 1256) or treatment as usual (n = 1131). PPI prescriptions were monitored 6 months before, 6 and 12 months after study initiation. In 49.2% of the consultations with arriba-PPI, the general practitioners and their patients made the decision to reduce or discontinue PPI intake. At 6 months, there was a significant reduction by 22.3% (95% CI 18.55 to 25.98; p < 0.0001) of defined daily doses (DDD) of PPI. A reduction of 3.3% (95% CI - 7.18 to + 0.62) was observed in the control group. At 12 months, the reduction of DDD-PPI remained stable in intervention patients (+ 3.5%, 95% CI - 0.99 to + 8.03), whereas control patients showed a reduction of DDD-PPI (- 10.2%, 95% CI - 6.01 to - 14.33). Consultation with arriba-PPI led to reduced prescription rates of PPI in primary care practices. Arriba-PPI can be a helpful tool for general practitioners to start a conversation with their patients about risks of long-term PPI intake, reduction or deprescribing unnecessary PPI medication.


Alteration in cardiac uncoupling proteins and eNOS gene expression following high-intensity interval training in favor of increasing mechanical efficiency.
High-intensity interval training (HIIT) increases energy expenditure and mechanical energy efficiency. Although both uncoupling proteins (UCPs) and endothelial nitric oxide synthase (eNOS) affect the mechanical efficiency and antioxidant capacity, their effects are inverse. The aim of this study was to determine whether the alterations of cardiac UCP2, UCP3, and eNOS mRNA expression following HIIT are in favor of increased mechanical efficiency or decreased oxidative stress. Wistar rats were divided into five groups: control group (n=12), HIIT for an acute bout (AT1), short term HIIT for 3 and 5 sessions (ST3 and ST5), long-term training for 8 weeks (LT) (6 in each group). The rats of the training groups were made to run on a treadmill for 60 min in three stages: 6 min running for warm-up, 7 intervals of 7 min running on treadmill with a slope of 5° to 20° (4 min with an intensity of 80-110% VO2max and 3 min at 50-60% VO2max), and 5-min running for cool-down. The control group did not participate in any exercise program. Rats were sacrificed and the hearts were extracted to analyze the levels of UCP2, UCP3 and eNOS mRNA by RT-PCR. UCP3 expression was increased significantly following an acute training bout. Repeated HIIT for 8 weeks resulted in a significant decrease in UCPs mRNA and a significant increase in eNOS expression in cardiac muscle. This study indicates that Long term HIIT through decreasing UCPs mRNA and increasing eNOS mRNA expression may enhance energy efficiency and physical performance.


Continued use of retracted papers: Temporal trends in citations and (lack of) awareness of retractions shown in citation contexts in biomedicine.
We present the first database-wide study on the citation contexts of retracted papers, which covers 7,813 retracted papers indexed in PubMed, 169,434 citations collected from iCite, and 48,134 citation contexts identified from the XML version of the PubMed Central Open Access Subset. Compared with previous citation studies that focused on comparing citation counts using two time frames (i.e., preretraction and postretraction), our analyses show the longitudinal trends of citations to retracted papers in the past 60 years (1960-2020). Our temporal analyses show that retracted papers continued to be cited, but that old retracted papers stopped being cited as time progressed. Analysis of the text progression of pre- and postretraction citation contexts shows that retraction did not change the way the retracted papers were cited. Furthermore, among the 13,252 postretraction citation contexts, only 722 (5.4%) citation contexts acknowledged the retraction. In these 722 citation contexts, the retracted papers were most commonly cited as related work or as an example of problematic science. Our findings deepen the understanding of why retraction does not stop citation and demonstrate that the vast majority of postretraction citations in biomedicine do not document the retraction.


Development of the polyurethane sponge as a delivery system for aryl 4-guanidinobenzoates.
The Today Contraceptive Sponge was evaluated as a vehicle for the delivery of aryl 4-guanidinobenzoates (AGs) which are highly active sperm acrosin inhibitors. Studies in animals have shown that several AGs are more potent vaginal contraceptives and less irritating to the vagina than nonoxynol-9 (N-9), the most frequently used active ingredient in commercial vaginal contraceptive formulations. Neither nonoxynol-9 nor the material that could be solubilized from the sponge matrix altered the enzyme-inhibitory activity of 4'-acetamidophenyl 4-guanidinobenzoate HCl (AGB), 4'-carboxyphenyl 4-guanidinobenzoate HCl (EGB) or 4'-carbomethoxyphenyl 4-guanidinobenzoate HCl (MSGB). Besides being acrosin inhibitors, all three AGs exhibited antimotility activity towards human spermatozoa, EGB being as potent as N-9. The antimotility effects of the AGs and N-9 were additive. For subsequent studies, AGB was used as the model compound. Manufacture of the AGB-containing sponges did not affect the chemical structure of AGB. Good release rates of AGB were obtained from the sponges over a 7-day period. The release rates were 20-50% higher when the sponges also contained N-9. These results indicate that certain AGs exert a dual contraceptive action on spermatozoa by inhibiting both the sperm enzyme acrosin and sperm motility. Furthermore, the polyurethane sponge appears to be a convenient and satisfactory long-term delivery system for the AGs. A mixture of N-9 and AG can be used clinically because these compounds have no adverse effects on each other.


Identification of a quality-control mechanism for mRNA 5'-end capping.
The 7-methylguanosine cap structure at the 5' end of eukaryotic messenger RNAs is a critical determinant of their stability and translational efficiency. It is generally believed that 5'-end capping is a constitutive process that occurs during mRNA maturation and lacks the need for a quality-control mechanism to ensure its fidelity. We recently reported that the yeast Rai1 protein has pyrophosphohydrolase activity towards mRNAs lacking a 5'-end cap. Here we show that, in vitro as well as in yeast cells, Rai1 possesses a novel decapping endonuclease activity that can also remove the entire cap structure dinucleotide from an mRNA. This activity is targeted preferentially towards mRNAs with unmethylated caps in contrast to the canonical decapping enzyme, Dcp2, which targets mRNAs with a methylated cap. Capped but unmethylated mRNAs generated in yeast cells with a defect in the methyltransferase gene are more stable in a rai1-gene-disrupted background. Moreover, rai1Δ yeast cells with wild-type capping enzymes show significant accumulation of mRNAs with 5'-end capping defects under nutritional stress conditions of glucose starvation or amino acid starvation. These findings provide evidence that 5'-end capping is not a constitutive process that necessarily always proceeds to completion and demonstrates that Rai1 has an essential role in clearing mRNAs with aberrant 5'-end caps. We propose that Rai1 is involved in an as yet uncharacterized quality control process that ensures mRNA 5'-end integrity by an aberrant-cap-mediated mRNA decay mechanism.


Fungal keratitis.
Fungal keratitis, or keratomycoses, are corneal infections which must be considered in cases of corneal trauma, prior corneal surgery, chronic ocular surface disease, topical corticosteroids or contact lens wear. Filamentous fungi or yeasts may be involved. Presenting clinical features such as corneal infiltrates with feathery edges and/or raised surface, intact epithelium with deep stromal involvement, satellite lesions, endothelial plaques, lack of improvement with antibiotics and worsening with steroids are suggestive of fungal keratitis. Corneal scraping for laboratory examination is mandatory. Medical management with antifungal eye drops and systemic agents should be started as soon as possible. Surgical interventions are required in a significant number of cases to control the infection. The prognosis of fungal keratitis is worse than that of bacterial keratitis.


Integrated mass spectrometry-based analysis of plasma glycoproteins and their glycan modifications.
We present a protocol for the identification of glycosylated proteins in plasma followed by elucidation of their individual glycan compositions. The study of glycoproteins by mass spectrometry is usually based on cleavage of glycans followed by separate analysis of glycans and deglycosylated proteins, which limits the ability to derive glycan compositions for individual glycoproteins. The methodology described here consists of 2D HPLC fractionation of intact proteins and liquid chromatography-multistage tandem mass spectrometry (LC-MS/MS(n)) analysis of digested protein fractions. Protein samples are separated by 1D anion-exchange chromatography (AEX) with an eight-step salt elution. Protein fractions from each of the eight AEX elution steps are transferred onto the 2D reversed-phase column to further separate proteins. A digital ion trap mass spectrometer with a wide mass range is then used for LC-MS/MS(n) analysis of intact glycopeptides from the 2D HPLC fractions. Both peptide and oligosaccharide compositions are revealed by analysis of the ion fragmentation patterns of glycopeptides with an intact glycopeptide analysis pipeline.


Electroactive Amphiphiles for Addressable Supramolecular Nanostructures.
In this focus review we aim to highlight an exciting class of materials, electroactive amphiphiles (EAAs). This class of functional amphiphilic molecules has been the subject of sporadic investigations over the last few decades, but little attempt has been made to date to gather or organise these investigations into a logical fashion. Here we attempted to gather the most important contributions, provide a framework in which to discuss them, and, more importantly, point towards the areas where we believe these EAAs will contribute to solving wider scientific problems and open new opportunities. Our discussions cover materials based on low molecular weight ferrocenes, viologens and anilines, as well as examples of polymeric and supramolecular EAAs. With the advances of modern analytical techniques and new tools for modelling and understanding optoelectronic properties, we believe that this area of research is ready for further exploration and exploitation.


Persistent mucosal abnormalities in coeliac disease are not related to the ingestion of trace amounts of gluten.
It is expected that in patients with coeliac disease the small-bowel mucosal mucosa will return to normal if they adhere to a gluten-free diet (GFD). However, in many this is not the case. This study aims to determine whether this persistent villous atrophy (VA) could be due to continued ingestion of the trace amounts of gluten in 'gluten-free' foods, as defined by the WHO/FAO Codex Alimentarius. Duodenal biopsy specimens from 89 adults with long-standing coeliac disease were examined, and the findings correlated with their form of gluten-free diet. In 51 subjects the duodenal specimen was normal, whereas in 38 there was villous atrophy (partial, 28; subtotal, 8; total, 2). There was no relationship between the presence or absence of VA and ingestion of either a GFD as defined by the Codex Alimentarius (Codex-GFD; 39 patients) or a GFD that contained no detectable gluten (NDG diet: 50 patients). Intraepithelial lymphocyte counts were higher, and lactase levels lower, in subjects with an abnormal biopsy specimen than in those in whom it was normal. However, within each of these biopsy groups there was no difference in these variables between patients on a Codex-GFD and those on an NDG-GFD. IgA antigliadin antibody was detected in 4 of 29 patients on a Codex-GFD and in 3 of 13 on a NDG-GFD (NS). The persistent mucosal abnormalities seen in patients with coeliac disease on a GFD are not due to the ingestion of trace amounts of gluten. The consequences of these abnormalities have yet to be determined.


Transition from the traditional head nurse to the nurse manager of the 90's.
This article was written in order to summarize the issues which must be considered by nursing administrators as the new nurse manager role is implemented and optimized. The writing of the article was prompted for two reasons. The author was unable to find an article with appropriate breadth--which envisioned this role change within the context of the entire organization. Most articles relating to the topic were restricted to nursing and/or to several main issues. Secondly, although many nurse administrators state that the nurse manager role is in place, there are definite problems with its effectiveness as noted by comments from both nurse managers as well as nursing directors. Consequently as this role change was planned and implemented at the Ottawa Civic Hospital, attention was provided to those mechanisms required to enhance effectiveness of the role. The article was written to include sufficient breadth such that this role change is planned within the context of the entire management philosophy of the organization.


Development, implementation and validation of resource-stratified guidelines in low-income and middle-income countries: a scoping review protocol.
Nearly every field of medicine has some form of clinical practice guidelines. However, only within the past 5-10 years has the medical community acknowledged the need for well-developed guidelines tailored to the local healthcare needs and the resources available. In most low-income and middle-income countries (LMICs), healthcare workers depend on guidelines developed in high-income countries (HICs), yet many interventions validated in a HIC are ineffective when implemented in an LMIC. The variation in infrastructure, medical personnel, technology and environmental conditions exhibited in LMICs relative to HICs necessitates a careful appraisal of the evidence base used in clinical guideline recommendations. This review aims to map the use of resource-stratified guidelines across all fields of medicine. The review seeks to answer three questions for the identified guidelines: (1) what was the method of development, (2) have they been implemented and, if so, (3) have they been validated. The search strategy will aim to locate studies from inception to November 2021. An initial limited search of PubMed and Scopus was undertaken to identify articles on the topic. The text words contained in the titles and abstracts of relevant articles, and the index terms used to describe the articles were used to develop a full search strategy for PubMed and Scopus. This scoping review will be conducted in accordance with the Joanna Briggs Institute (JBI) methodology for scoping reviews. Data to be extracted from each study will include population characteristics of both developers and intended implementation population, medical specialty, validation status, method of guideline development, whether the study is consensus or evidence-based in addition to a summary of recommendations for practice. Ethical approval is not required for this review. The plan for dissemination is to publish review findings in a peer-reviewed journal.


Quantifying the contribution of leading causes of death to mortality decline among older people in England, 1991-2005.
This paper quantifies the contribution of leading causes of death to mortality change between 1991 and 2005 for people aged 50 years and over in England. Between 1971 and 2005 the life expectancy of men aged 50 years increased by more than in the whole of the rest of the 20(th) century. The ageing population has not only had an important impact on health and social services, but was responsible for sparking the pensions crisis affecting both the public and commercial sector. A cross-sectional analysis was used to quantify trends in cause-specific mortality in terms of absolute and relative change between 1991 and 2005 in the population aged 50 and over. Absolute change is quantified in terms of the numbers of deaths prevented or postponed (or conversely, increased or brought-forward) in a year compared to deaths in the baseline year. The percentage change in age-standardised rates was used to identify relative change in causes of death. Between 1991 and 2005 there was a continuous decline in overall all-cause death rates for people aged 50 and over. Age-standardised mortality declined by 30 per cent for men, from 3,216 per 100,000 men to 2,267 per 100,000. This resulted in 86,477 fewer male deaths in 2005 than would have occurred had 1991 rates persisted. For women the age-standardised mortality rate declined by 20 per cent from 2,032 per 100,000 to 1,626 per 100,000, resulting in 48,406 deaths postponed (or fewer deaths) in 2005.Of the total numbers of deaths postponed in 2005, ischaemic heart disease contributed the largest share for both men (45,244 deaths - 52.3 per cent) and women (33,601 - 69.4 per cent).The greatest decline in the mortality rate was observed for influenza, for which age-standardised rates fell by 89 per cent for men and 93 per cent for women. However the proportion of deaths in which influenza was the underlying cause was extremely small and so did not contribute a large proportion in terms of the total fall in numbers of deaths.Mortality rates from some conditions increased. Liver disease rates demonstrated some of the largest increases for both men and women aged 50 and over. For men the age-standardised mortality rate from liver disease increased by 104 per cent, resulting in 1,434 more deaths in 2005 than in 1991. The trends of decreasing mortality rates from ischaemic heart disease and stroke have continued into the 21(st) century, however both causes continue to be the biggest killers in England. They are projected to remain so, and consequently, to contribute significantly to the burden of disease in the population.The steady increase in liver disease mortality identified highlights the importance of tackling alcohol misuse as a public health priority.


Renal Replacement Therapy Modality in the ICU and Renal Recovery at Hospital Discharge.
Acute kidney injury requiring renal replacement therapy is a major concern in ICUs. Initial renal replacement therapy modality, continuous renal replacement therapy or intermittent hemodialysis, may impact renal recovery. The aim of this study was to assess the influence of initial renal replacement therapy modality on renal recovery at hospital discharge. Retrospective cohort study of all ICU stays from January 1, 2010, to December 31, 2013, with a "renal replacement therapy for acute kidney injury" code using the French hospital discharge database. Two hundred ninety-one ICUs in France. A total of 1,031,120 stays: 58,635 with renal replacement therapy for acute kidney injury and 25,750 included in the main analysis. None. PPatients alive at hospital discharge were grouped according to initial modality (continuous renal replacement therapy or intermittent hemodialysis) and included in the main analysis to identify predictors of renal recovery. Renal recovery was defined as greater than 3 days without renal replacement therapy before hospital discharge. The main analysis was a hierarchical logistic regression analysis including patient demographics, comorbidities, and severity variables, as well as center characteristics. Three sensitivity analyses were performed. Overall mortality was 56.1%, and overall renal recovery was 86.2%. Intermittent hemodialysis was associated with a lower likelihood of recovery at hospital discharge; odds ratio, 0.910 (95% CI, 0.834-0.992) p value equals to 0.0327. Results were consistent across all sensitivity analyses with odds/hazards ratios ranging from 0.883 to 0.958. In this large retrospective study, intermittent hemodialysis as an initial modality was associated with lower renal recovery at hospital discharge among patients with acute kidney injury, although the difference seems somewhat clinically limited.


Membrane-permeable luciferin esters for assay of firefly luciferase in live intact cells.
Five esters of luciferin were synthesized and compared with native luciferin as substrates for firefly luciferase expressed in live intact mammalian cells. The esters themselves were not substrates for purified luciferase, but four were substrates for a purified esterase and all appeared to be hydrolysed to luciferin within mammalian cells. At a substrate concentration of 0.01 mM, the peak luminescence from the cos cells expressing luciferase was up to 6-fold greater with the esters than with unmodified luciferin. At 0.1 mM, the difference between luciferin and the esters was decreased. The kinetics of the luminescent signal with the different luciferin esters varied significantly, indicating possible differences in the rates of uptake, breakdown and enzyme inhibition. The esters did not support luminescence from Escherichia coli cells expressing firefly luciferase, suggesting a lack of appropriate esterase activity in this particular strain. The esters could be useful for the assay of luciferase expression in intact mammalian cells when luciferin levels are limiting, for example in tissues, and in plants. Alternative luciferin derivatives may allow further improvements in sensitivity.


Transcriptome analysis of human induced excitatory neurons supports a strong effect of clozapine on cholesterol biosynthesis.
Antipsychotics are known to modulate dopamine and other neurotransmitters which is often thought to be the mechanism underlying their therapeutic effects. Nevertheless, other less studied consequences of antipsychotics on neuronal function may contribute to their efficacy. Revealing the complete picture behind their action is of paramount importance for precision medicine and accurate drug selection. Progress in cell engineering allows the generation of induced pluripotent stem cells (iPSCs) and their differentiation to a variety of neuronal types, providing new tools to study antipsychotics. Here we use excitatory cortical neurons derived from iPSCs to explore their response to therapeutic levels of Clozapine as measured by their transcriptomic output, a proxy for neuronal homeostasis. To our surprise, but in agreement with the results of many investigators studying glial-like cells, Clozapine had a very strong effect on cholesterol metabolism. More than a quarter (12) of all annotated cholesterol genes (46) in the genome were significantly changed at FDR < 0.1, all upregulated. This is a 35-fold enrichment with an adjusted p = 8 × 10-11. Notably no other functional category showed evidence of enrichment. Cholesterol is a major component of the neuronal membrane and myelin but it does not cross the blood brain barrier, it is produced locally mostly by glia but also by neurons. By singling out increased expression of cholesterol metabolism genes as the main response of cortical excitatory neurons to antipsychotics, our work supports the hypothesis that cholesterol metabolism may be a contributing mechanism to the beneficial effects of Clozapine and possibly other antipsychotics.


Betaine prevents cognitive dysfunction by suppressing hippocampal microglial activation in chronic social isolated male mice.
Chronic social isolation (SI) stress, which became more prevalent during the COVID-19 pandemic, contributes to abnormal behavior, including mood changes and cognitive impairment. Known as a functional nutrient, betaine has potent antioxidant and anti-inflammatory properties in vivo. However, whether betaine can alleviate the abnormal behavior induced by chronic SI in mice remains unknown. In this study, we investigated the efficacy of betaine in the treatment of behavioral changes and its underlying mechanism. Three-week-old male mice were randomly housed for 8 weeks in either group housing (GH) or SI. The animals were divided into normal saline-treated GH, normal saline-treated SI, and betaine-treated SI groups in the sixth week. The cognitive and depression-like behavior was determined in the eighth week. We found that long-term betaine administration improved cognitive behavior in SI mice but failed to prevent depression-like behavior. Moreover, long-term betaine administration inhibited hippocampal microglia over-activation and polarized microglia toward the M2 phenotype, which effectively inhibited the expression of inflammatory factors in SI mice. Finally, the protective effect of betaine treatment in SI mice might not be due to altered activity of the hypothalamic-pituitary-adrenal axis. Collectively, our findings reveal that betaine can improve SI-induced cognitive impairment, thus providing an alternative natural source for the prevention of memory loss caused by SI or loneliness.


Post-class naps boost declarative learning in a naturalistic school setting.
Laboratory evidence of a positive effect of sleep on declarative memory consolidation suggests that naps can be used to boost school learning in a scalable, low-cost manner. The few direct investigations of this hypothesis have so far upheld it, but departed from the naturalistic setting by testing non-curricular contents presented by experimenters instead of teachers. Furthermore, nap and non-nap groups were composed of different children. Here we assessed the effect of post-class naps on the retention of Science and History curricular contents presented by the regular class teacher to 24 students from 5th grade. Retention was repeatedly measured 3-4 days after content learning, with weekly group randomization over 6 consecutive weeks. Contents followed by long naps (>30 min), but not short naps (<30 min), were significantly more retained than contents followed by waking (Cohen's d = 0.7962). The results support the use of post-class morning naps to enhance formal education.


[Glucose-6-phosphate dehydrogenase deficiency: clinical presentation and eliciting factors].
Glucose-6-phosphate dehydrogenase (G6PD) deficiency, a hereditary X-linked disorder, is the most common enzymatic disorder of red blood cells in humans, affecting more than 200 million people worldwide. The prevalence is increasing in the Netherlands due to immigration of people from the Middle East and Africa. We present three different clinical manifestations of G6PD deficiency: neonatal jaundice, haemolysis provoked by infection and haemolysis caused by fava beans. The pathophysiology and treatment are discussed. Furthermore a recent update of chemicals which should be avoided in G6PD deficiency is provided.


Heterogeneity and Fgf dependence of adult neural progenitors in the zebrafish telencephalon.
Adult telencephalic neurogenesis is a conserved trait of all vertebrates studied. It has been investigated in detail in rodents, but very little is known about the composition of neurogenic niches and the cellular nature of progenitors in nonmammalian vertebrates. To understand the components of the progenitor zones in the adult zebrafish telencephalon and the link between glial characteristics and progenitor state, we examined whether canonical glial markers are colocalized with proliferation markers. In the adult zebrafish telencephalon, we identify heterogeneous progenitors that reside in two distinct glial domains. We find that the glial composition of the progenitor zone is linked to its proliferative behavior. Analyzing both fast-cycling proliferating cells as well as slowly cycling progenitors, we find four distinct progenitor types characterized by differential expression of glial markers. Importantly, a significant proportion of progenitors do not display typical radial glia characteristics. By blocking or activating Fgf signaling by misexpression of a dominant negative Fgf-receptor 1 or Fgf8a, respectively, we find that ventral and dorsal progenitors in the telencephalon also differ in their requirement for Fgf signaling. Together with data on the expression of Fgf signaling components in the ventricular zone of the telencephalon, this suggests that Fgf signaling directly regulates proliferation of specific subsets of adult telencephalic progenitors in vivo. Taken together our results show that adult neural progenitor cells are heterogeneous with their respect to distribution into two distinct glial domains and their dependence upon Fgf signaling as a proliferative cue in the zebrafish telencephalon.


Higher HIV-1 RNA cutoff level required in cerebrospinal fluid than in blood to predict positive HIV-1 isolation.
HIV-1 can be isolated from the vast majority of blood samples taken from HIV-1-seropositive patients not treated with antiretroviral drugs. Isolation rates from cerebrospinal fluid (CSF) samples are considerably lower, ranging between 20-70%. The objective of this study was to determine the cutoff levels for HIV-1 RNA that would yield a positive predictive value > or =90% for positive virus isolation from CSF and blood. Quantitative HIV-1 RNA PCR (Amplicor HIV monitor, version 1.0, Roche Diagnostic Systems) and virus isolation were used to examine 303 CSF samples and 278 paired blood samples from 157 HIV-1-seropositive patients. Patients on antiretroviral treatment provided 140 of the CSF samples and 131 of the blood samples. CSF samples that were positive by culture numbered 137 of 303 (45%), as compared with 216 of 278 (78%) blood samples. In the case of samples taken from patients with antiretroviral treatment, 28% were positive by culture from CSF and 63% from blood. As expected, mean HIV-1 RNA levels were higher in CSF and blood samples positive by culture than in samples negative by culture. A cutoff level of >5,000 HIV-1 RNA copies/ml was required to yield a positive predictive value for positive virus isolation from CSF samples of > or =90%, whereas the cutoff level for blood samples was just above the detection limit of the assay (>200 HIV-1 copies/ml).


Multiomics analysis of rheumatoid arthritis yields sequence variants that have large effects on risk of the seropositive subset.
To find causal genes for rheumatoid arthritis (RA) and its seropositive (RF and/or ACPA positive) and seronegative subsets. We performed a genome-wide association study (GWAS) of 31 313 RA cases (68% seropositive) and ~1 million controls from Northwestern Europe. We searched for causal genes outside the HLA-locus through effect on coding, mRNA expression in several tissues and/or levels of plasma proteins (SomaScan) and did network analysis (Qiagen). We found 25 sequence variants for RA overall, 33 for seropositive and 2 for seronegative RA, altogether 37 sequence variants at 34 non-HLA loci, of which 15 are novel. Genomic, transcriptomic and proteomic analysis of these yielded 25 causal genes in seropositive RA and additional two overall. Most encode proteins in the network of interferon-alpha/beta and IL-12/23 that signal through the JAK/STAT-pathway. Highlighting those with largest effect on seropositive RA, a rare missense variant in STAT4 (rs140675301-A) that is independent of reported non-coding STAT4-variants, increases the risk of seropositive RA 2.27-fold (p=2.1×10-9), more than the rs2476601-A missense variant in PTPN22 (OR=1.59, p=1.3×10-160). STAT4 rs140675301-A replaces hydrophilic glutamic acid with hydrophobic valine (Glu128Val) in a conserved, surface-exposed loop. A stop-mutation (rs76428106-C) in FLT3 increases seropositive RA risk (OR=1.35, p=6.6×10-11). Independent missense variants in TYK2 (rs34536443-C, rs12720356-C, rs35018800-A, latter two novel) associate with decreased risk of seropositive RA (ORs=0.63-0.87, p=10-9-10-27) and decreased plasma levels of interferon-alpha/beta receptor 1 that signals through TYK2/JAK1/STAT4. Sequence variants pointing to causal genes in the JAK/STAT pathway have largest effect on seropositive RA, while associations with seronegative RA remain scarce.


Cyclic AMP regulation of the human glycoprotein hormone alpha-subunit gene is mediated by an 18-base-pair element.
cAMP regulates transcription of the gene encoding the alpha-subunit of human chorionic gonadotropin (hCG) in choriocarcinoma cells (BeWo). To define the sequences required for regulation by cAMP, we inserted fragments from the 5' flanking region of the alpha-subunit gene into a test vector containing the simian virus 40 early promoter (devoid of its enhancer) linked to the bacterial chloramphenicol acetyltransferase (CAT) gene. Results from transient expression assays in BeWo cells indicated that a 1500-base-pair (bp) fragment conferred cAMP responsiveness on the CAT gene regardless of position or orientation of the insert relative to the viral promoter. A subfragment extending from position -169 to position -100 had the same effect on cAMP-induced expression. Furthermore, the entire stimulatory effect could be achieved with an 18-bp synthetic oligodeoxynucleotide corresponding to a direct repeat between positions -146 and -111. In the absence of cAMP, the alpha-subunit 5' flanking sequence also enhanced transcription from the simian virus 40 early promoter. We localized this enhancer activity to the same -169/-100 fragment containing the cAMP response element. The 18-bp element alone, however, had no effect on basal expression. Thus, this short DNA sequence serves as a cAMP response element and also functions independently of other promoter-regulatory elements located in the 5' flanking sequence of the alpha-subunit gene.


[Clinical outcome and factors affecting surgical decision for repair versus replacement in patients with mitral regurgitation].
We aimed to identify characteristics differentiating patients undergoing mitral valve replacement versus valve repair for mitral regurgitation (MR) and to investigate retrospectively mid-term clinical and functional outcomes. From January, 2004 to January, 2009 146 patients underwent mitral valve surgery (62 male / 84 female; age: 55.9+/-13.6 [18-80] years) by one surgical team. Mitral valve replacement was performed in 101 patients (69.2 %) and valve repair was performed in 45 patients (30.8%). Mean follow-up time was 586+/-413 days. Life tables were constructed for the analysis of 5-year complication free survival and comparisons were performed between the groups using Log-rank test within 95%CI. The choice of surgical technique depended on the etiology of MR. Degenerative (p=0.001) and ischemic (p=0.014) MR were more common in patients undergoing repair whereas patients with complex rheumatic mitral valve disease (p=0.001) with subvalvular involvement commonly underwent replacement. Overall 30-day mortality was 3.2% (replacement, 3.96%vs repair, 2.22%, p=0.59). Although there was no significant difference between the groups regarding baseline left ventricular ejection fraction (EF) (ischemic p=0.61; non-ischemic p=0.34), improvement was more pronounced in the repair group for both etiologies (ischemic MR, p=0.001; non- ischemic MR p=0.002). Survival at 5-years was 91.7+/-4.7% after repair and 83.5+/-9.2% after replacement, respectively (p=0.83). Freedom from grade 2 or more mitral regurgitation, reoperation, endocarditis, and thromboembolism were 95+/-5% vs 97+/-3% (p=0.71); 95+/-4% vs 98+/-2% (p=0.98); 94+/-4% vs 100% (p=0.16); and 85+/-8% vs 100% (p=0.095) in replacement and repair groups, respectively. This study demonstrates that mitral valve repair is associated with an acceptable operative mortality, satisfactory mid-term survival and better preservation of left ventricular function. Significant differences in favor of repair are expected in long-term follow-up particularly regarding freedom from thromboembolism and endocarditis.


Francisella philomiragia subsp. noatunensis subsp. nov., isolated from farmed Atlantic cod (Gadus morhua L.).
Seven bacterial isolates from farmed Atlantic cod displaying chronic granulomatous disease were characterized by phenotypic and molecular taxonomic methods. The isolates were Gram-negative, facultatively intracellular, non-motile, strictly aerobic coccobacilli which produced H(2)S from cysteine-supplemented media and are therefore phenotypically consistent with members of the genus Francisella. Comparison of 16S rRNA gene sequences and six partial housekeeping gene sequences (groEL, shdA, rpoB, rpoA, pgm and atpA) confirmed the organism as a member of the genus Francisella, with Francisella philomiragia as its closest relative (99.3 % 16S rRNA gene sequence similarity, 92.2-99.0 % housekeeping gene sequence similarity). Despite the close relationship with F. philomiragia, isolates from Atlantic cod could be readily distinguished phenotypically and genetically from F. philomiragia ATCC 25015(T). DNA-DNA hybridization studies revealed a mean reassociation value of 68 %. Thus, on the basis of phenotypic and molecular genetic evidence, we propose that the strains isolated from Atlantic cod should be recognized as Francisella philomiragia subsp. noatunensis subsp. nov. with the type strain 2005/50/F292-6C(T) (=NCIMB 14265(T)=LMG 23800(T)). Francisella philomiragia ATCC 25015(T) (=DSM 735(T)) is reclassified as Francisella philomiragia subsp. philomiragia subsp. nov.


Paediatric gastrointestinal disorders in SARS-CoV-2 infection: Epidemiological and clinical implications.
The coronavirus disease 2019 (COVID-19) pandemic is a threat worldwide for individuals of all ages, including children. Gastrointestinal manifestations could be the initial presenting manifestation in many patients, especially in children. These symptoms are more common in patients with severe disease than in patients with non-severe disease. Approximately 48.1% of patients had a stool sample that was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral RNA. Children typically form 1%-8% of all laboratory-confirmed cases of SARS-CoV-2. Gastrointestinal manifestations of COVID-19 in children are not rare, with a prevalence between 0 and 88%, and a wide variety of presentations, including diarrhoea, vomiting, and abdominal pain, can develop before, with or after the development of respiratory symptoms. Atypical manifestations such as appendicitis or liver injury could also appear, especially in the presence of multisystem inflammatory disease. In this review, we discussed the epidemiology of COVID-19 gastrointestinal diseases in children as well as their implications on the diagnosis, misdiagnosis, prognosis, and faecal-oral transmission route of COVID-19 and the impact of gastrointestinal diseases on the gut microbiome, child nutrition, and disease management.


Heterogeneity of murine regulatory T cells. I. Subpopulations of amplifier and suppressor T cells.
Immunization of C3H/HeJ mice with 4 X 10(9) SRBC yields a whole splenic T-cell population which can, upon transfer, specifically suppress recipient direct and indirect plaque-forming cells (PFC) responses to sheep erythrocytes (SRBC). Discontinuous bovine serum albumin density gradient fractionation of these T cells demonstrated a population of low density T cells which augmented and a population of high density T cells which suppressed recipient responses irrespective of the number of T cells transferred. Moreover, infusion of admixtures of low and high density cells resulted in intermediate regulatory functions which could be predicted by knowing the regulatory capacity of each population alone. In addition to heterogeneity existing among regulatory T cells as regards amplification and suppression, it appeared that heterogeneity existed within the suppressor T population. Thus, T cells capable of inhibiting direct PFC could be distinguished from those suppressing indirect PFC by their differential localization in peripheral lymphoid tissue, differences in the dissipation of suppressive influences during incubation at 37 degrees C, and by differences in the possible requirement for adherent cell populations. While the relative frequency of both low density amplifier and high density suppressor cells increased with the dose of SRBC used for their induction, it appeared that suppressor cells might be generated in response to feedback signals from amplifier cells. These studies indicate that further delineation of heterogeneity existing within suppressor populations may be helpful in defining mechanisms required for the induction and manifestation of suppressive regulatory forces.


Reliability and validity of the pediatric feeding and swallowing disorders family impact scale for Turkish children with cerebral palsy by endoscopic evaluation.
Umay E, Gündoğdu İ, Öztürk EA. Reliability and validity of the pediatric feeding and swallowing disorders family impact scale for Turkish children with cerebral palsy by endoscopic evaluation. Turk J Pediatr 2019; 61: 741-748. The caregivers of children with cerebral palsy (CP) have high mood disorders and stress levels. This study was aimed to conduct validity and reliability of Turkish version of The Pediatric Feeding and Swallowing Disorders Family Impact Scale (PFSDFIS) by using an objective method. This study was performed in our physical medicine and rehabilitation (PMR) clinic between July 2016 and July 2018. This study was performed with 251 children with CP who had complaint of swallowing and/or feeding problems, and their primer caregivers. Cronbach`s alpha and corrected item-total correlations were used to assess internal consistency. Test and retest reliability studies were also conducted. The construct validity was assessed using the dysphagia level defined with flexible fiberoptic endoscopic evaluation of swallowing and Impact on Family Scale (IFS). Total score of T-PFSDFIS was correlated to the dysphagia level by using FEES. Results showed, Cronbach's alpha value of the scale to be 0.821. Corrected item-to-total correlations ranged from 0.729 to 0.911. Test-retest reliability coefficients was calculated with intra-class correlation coefficient (ICC), the total score was 0.989. A negative significant good level correlation was found between the dysphagia level by using endoscopic evaluation and the T- PFSDFIS total score as well as between total scores of IFS and T-PFSDFIS. In subgroup analysis; the lowest value was in normal swallowing and significantly different from all dysphagia levels. In conclusion; this scale is effective in reflecting the influence of caregivers on the severity of dysphagia measured objectively and T-PFSDFIS is a valid and reliable scale for Turkish children with CP.


Spin-induced angular momentum switching.
When light is transmitted through optically inhomogeneous and anisotropic media the spatial distribution of light can be modified according to its input polarization state. A complete analysis of this process, based on the paraxial approximation, is presented, and we show how it can be exploited to produce a spin-controlled change in the orbital angular momentum of light beams propagating in patterned space-variant optical axis phase plates. We also unveil a new effect: the development of a strong modulation in the angular momentum change upon variation of the optical path through the phase plates.


Adapting Artifact Subspace Reconstruction Method for SingleChannel EEG using Signal Decomposition Techniques.
Artifact removal from electroencephalography (EEG) data is a crucial step in the analysis of neural signals. One method that has been gaining popularity in recent years is Artifact Subspace Reconstruction (ASR), which is highly effective in eliminating large amplitude and transient artifacts in EEG data. However, traditional ASR is not possible to use with single-channel EEG data. In this study, we propose incorporating signal decomposition techniques such as ensemble empirical mode decomposition (EEMD), wavelet transform (WT), and singular spectrum analysis (SSA) into ASR, to decompose single-channel data into multiple components. This allows the ASR process to be applied effectively to the data. Our results show that the proposed single-channel version of ASR outperforms its counterpart Independent Component Analysis (ICA) methods when tested on two open datasets. Our findings indicate that ASR has significant potential as a powerful tool for removing artifacts from EEG data analysis.Clinical Relevance- This provided artifact removal technique for single-channel EEG.


Hyperthermia as an adjuvant to radiotherapy in the treatment of malignant melanoma.
One hundred and fifteen cutaneous or lymph node metastases from malignant melanoma were treated with three fractions of irradiation alone in 8 days (62 tumours) or followed by heat either immediately (simultaneous treatment, 26 tumours) or after an interval of 3-4 h (sequential therapy, 27 tumours). In addition, three tumours were treated unsuccessfully with heat alone. The total doses of radiation varied between 15 and 30 Gy, allowing a dose-response analysis. For irradiation alone the isoeffective dose to obtain 50 per cent complete response (TCD50) was 26.3 Gy. Addition of heat reduced the TCD50 significantly (p less than 0.05) with a thermal enhancement ratio (TER) of 1.43 for simultaneous treatment and 1.24 for sequential therapy. Also the persistent local control at 18 months was improved by hyperthermia (56 per cent versus 86 per cent, p less than 0.05). However, simultaneous treatment also enhanced the acute skin response to the same extent as the tumour (TER 1.42 for severe erythema). This schedule thus gave no therapeutic gain. In contrast, no normal tissue enhancement was found after sequential treatment (TER 1.02). Such a treatment schedule resulted in a significantly improved therapeutic ratio of 1.22. This effect was especially prominent in larger tumours (if sufficiently heated) and an analysis corrected for volume showed a TER of 1.51. A special analysis was performed in patients with multiple lesions. 15 pairs of tumours were given the same radiation dose, with or without hyperthermia. Out of these, 11 showed a better response, three showed the same response, and only in one pair was the best response in the tumour obtained by radiation alone.


Electronic coherence and the kinetics of inter-complex energy transfer in light-harvesting systems.
We apply real-time path-integral dynamics simulations to characterize the role of electronic coherence in inter-complex excitation energy transfer (EET) processes. The analysis is performed using a system-bath model that exhibits the essential features of light-harvesting networks, including strong intra-complex electronic coupling and weak inter-complex coupling. Strong intra-complex coupling is known to generate both static and dynamic electron coherences, which delocalize the exciton over multiple chromophores and potentially influence the inter-complex EET dynamics. With numerical results from partial linearized density matrix (PLDM) real-time path-integral calculations, it is found that both static and dynamic coherence are correlated with the rate of inter-complex EET. To distinguish the impact of these two types of intra-complex coherence on the rate of inter-complex EET, we use Multi-Chromophore Förster Resonance Energy Transfer (MC-FRET) theory to map the original parameterization of the system-bath model to an alternative parameterization for which the effects of static coherence are preserved while the effects of dynamic coherence are largely eliminated. It is then shown that both parameterizations of the model (i.e., the original that supports dynamic coherence and the alternative that eliminates it), exhibit nearly identical EET kinetics and population dynamics over a wide range of parameters. These observations are found to hold for cases in which either the EET donor or acceptor is a dimeric complex and for cases in which the dimeric complex is either symmetric or asymmetric. The results from this study suggest that dynamic coherence plays only a minor role in the actual kinetics of inter-complex EET, whereas static coherence largely governs the kinetics of incoherent inter-complex EET in light-harvesting networks.


Purification of green fluorescent protein using a two-intein system.
A two-intein purification system was developed for the affinity purification of GFPmut3*, a mutant of green fluorescent protein. The GFPmut3* was sandwiched between two self-cleaving inteins. This approach avoided the loss of the target protein which may result from in vivo cleavage of a single intein tag. The presence of N- and C-terminal chitin-binding domains allowed the affinity purification by a single-affinity chitin column. After the fusion protein was expressed and immobilized on the affinity column, self-cleavage of the inteins was sequentially induced to release the GFPmut3*. The yield was 2.41 mg from 1 l of bacterial culture. Assays revealed that the purity was up to 98% of the total protein. The fluorescence and circular dichroism spectrum of GFPmut3* demonstrated that the purified protein retains the correctly folded structure and function.


Long-term results of a randomized trial on the sequencing of radiotherapy and chemotherapy in breast cancer.
A prospective, phase III randomized study was undertaken to compare the outcomes of 2 different radiotherapy and chemotherapy sequences in conservatively treated patients with breast cancer. Between January 1997 and November 2002, 206 patients operated of quadrantectomy and axillary dissection for breast cancer, candidates to receive adjuvant CMF chemotherapy (cyclophosphamide, methotrexate, and fluorouracil) were assigned to concurrent or sequential radiation treatment by using a balanced randomization method. Before randomization patients were stratified by tumor diameter, age, and lymph node status. The primary end point was the freedom from breast recurrence, and secondary end points were overall and disease-free survival. Overall outcomes were analyzed according to the intention-to-treat principle. All 206 patients enrolled and randomized in the trial were analyzed. The median follow-up was 111 months, with no patient lost for follow-up. No difference in 10-years breast recurrence-free, disease-free, metastasis-free, and overall survival rates was observed in the 2 treatment sequence groups. The Hazard Ratios, calculated for each prognostic factor, showed no difference in all outcomes between the 2 treatment sequences. No influence of the treatment sequence on long-term outcomes was observed in this trial. This finding suggests that to avoid an increased risk of distant recurrence or an excessive toxicity, radiation therapy may be delayed until after the end of the more, recently used, anthracycline-based chemotherapy without increasing the risk of breast recurrences, thus allowing the delivery of full-dose chemotherapy in patients at risk for systemic disease spread.


Diagnosis and monitoring denosumab therapy of giant cell tumors of bone: radiologic-pathologic correlation.
To determine the value of CT and dynamic contrast-enhanced (DCE-)MRI for monitoring denosumab therapy of giant cell tumors of bone (GCTB) by correlating it to histopathology. Patients with GCTB under denosumab treatment and monitored with CT and (DCE-)MRI (2012-2021) were retrospectively included. Imaging and (semi-)quantitative measurements were used to assess response/relapse. Tissue samples were analyzed using computerized segmentation for vascularization and number of neoplastic and giant cells. Pearson's correlation/Spearman's rank coefficient and Kruskal-Wallis tests were used to assess correlations between histopathology and radiology. Six patients (28 ± 8years; five men) were evaluated. On CT, good responders showed progressive re-ossification (+7.8HU/month) and cortical remodeling (woven bone). MRI showed an SI decrease relative to muscle on T1-weighted (-0.01 A.U./month) and on fat-saturated T2-weighted sequences (-0.03 A.U./month). Time-intensity-curves evolved from a type IV with high first pass, high amplitude, and steep wash-out to a slow type II. An increase in time-to-peak (+100%) and a decrease in Ktrans (-71%) were observed. This is consistent with microscopic examination, showing a decrease of giant cells (-76%), neoplastic cells (-63%), and blood vessels (-28%). There was a strong statistical significant inverse correlation between time-to-peak and microvessel density (ρ = -0.9, p = 0.01). Significantly less neoplastic (p = 0.03) and giant cells (p = 0.04) were found with a time-intensity curve type II, compared to a type IV. Two patients showed relapse after initial good response when stopping denosumab. Inverse imaging and pathological findings were observed. CT and (DCE-)MRI show a good correlation with pathology and allow adequate evaluation of response to denosumab and detection of therapy failure.


Changes in expression of transferrin, insulin-like growth factor 1, and interleukin 4 receptors after irradiation of cells of primary malignant brain tumor cell lines.
Various immunotoxins have been developed for the treatment of cancer. The toxin is internalized by target cells through cell-surface receptors, and it is essential for these receptors to be expressed for the immunotoxin to have specific anti-tumor activity. Radiation therapy is one of the main treatment modalities for primary malignant brain tumors. The purpose of this study was to determine whether radiation influences the expression of cell-surface receptors. Cells of one human medulloblastoma (Daoy) and two glioblastoma (U373-MG and T98-G) cell lines were tested by exposing the cells to a single dose of 5 Gy gamma rays. Expression of transferrin receptors, type-1 insulin-like growth factor receptors (IGF1R), and interleukin 4 receptors (IL4R) was measured by flow cytometry analysis on unirradiated cells and on cells 3 to 120 h after irradiation. In Daoy cells, the absolute expression index of transferrin receptors increased during the 24 h after irradiation with the greatest change of 26% above control at 9 h. The absolute expression index of IGF1R increased 26.5% above control at 12 h. The absolute expression index of IL4R decreased 9 h after irradiation. In U373-MG cells the absolute expression index of transferrin receptors increased during the 24 h after irradiation, and the greatest increase was 45% above control at 9 h. The absolute expression index of IGF1R increased during the 12 h after irradiation with a maximum increase of 33% above control at 6 h. The absolute expression index of IL4R decreased with time after irradiation. In T98-G cells, the absolute expression index of both transferrin receptors and IL4R decreased after irradiation. The results suggest that the expression of growth factor receptors on brain tumor cells may be influenced by radiation. The effect of ionizing radiation on receptor expression should be considered when administration of targeted toxin is combined with radiation. Similar studies with other growth factor receptors used in targeted toxin therapy are recommended.


Questionnaires on stigmatizing attitudes among healthcare students in Taiwan: development and validation.
People may be stigmatized if they have mental illness, emotional and behavioral disorders (EBD), or physical or intellectual disabilities. Being stigmatized adversely affects one's psychological well-being and quality of life. While occupational therapists frequently work with people with EBD and disabilities, all healthcare practitioners may encounter these populations, and stigmatizing attitudes of healthcare professionals towards such clients can negatively affect the therapeutic relationship, evaluation, and treatment. Therefore, understanding attitudes of healthcare students-as future practitioners in all fields of healthcare-towards people in this regard is fundamental to the future implementation of anti-stigma programs. We aimed to develop and test questionnaires for examining stigmatizing attitudes of healthcare students towards people with mental illness or disabilities and children with EBD. A literature review was conducted to identify surveys related to attitudes towards people with mental illness, EBD, and disabilities. Items that were pertinent to the concept of stigma were selected and modified to fit into the Taiwanese context. A total of 336 students from departments of occupational therapy, physical therapy, nursing, and medicine in 7 universities across Taiwan completed the questionnaires. Item analysis and factor analysis were used to examine the reliability and validity of the questionnaires. Gender differences were also considered. Factor analyses of the three questionnaires yielded factor structures that explained 61.34 to 67.15% of the variance, with Cronbach's α values ranging from 0.71 to 0.89. The Questionnaire on Stigmatizing Attitudes Towards Mental Illness consisted of 16 items with 4 subscales: deviant behavior, social isolation, negative stereotype, and self-stigma. The Questionnaire on Stigmatizing Attitudes Towards Children with EBD consisted of 14 items with 3 subscales: rejective attitude, negative stereotype, and deviant behavior. The Questionnaire on Stigmatizing Attitudes Towards Disabilities consisted of 10 items with 3 subscales: positive stereotype, negative stereotype, and pessimistic expectation. In addition, men had slightly higher stigmatizing attitudes than women. The results showed satisfactory factor structures and internal consistency, and thus support the use of these questionnaires to understand attitudes of healthcare students towards these populations. In addition, particular attention should be paid to gender differences in stigmatizing attitudes of healthcare students.


Searches for bridged bicyclic molecules in space-norbornadiene and its cyano derivatives.
The norbornadiene (NBD) molecule, C7H8, owes its fame to its remarkable photoswitching properties that are promising for molecular solar-thermal energy storage systems. Besides this photochemical interest, NBD is a rather unreactive species within astrophysical conditions and it should exhibit high photostability, properties that might also position this molecule as an important constituent of the interstellar medium (ISM)-especially in environments that are well shielded from short-wavelength radiation, such as dense molecular clouds. It is thus conceivable that, once formed, NBD can survive in dense molecular clouds and act as a carbon sink. Following the recent interstellar detections of large hydrocarbons, including several cyano-containing ones, in the dense molecular cloud TMC-1, it is thus logical to consider searching for NBD-which presents a shallow but non-zero permanent electric dipole moment (0.06 D)-as well as for its mono- and dicyano-substituted compounds, referred to as CN-NBD and DCN-NBD, respectively. The pure rotational spectra of NBD, CN-NBD, and DCN-NBD have been measured at 300 K in the 75-110 GHz range using a chirped-pulse Fourier-transform millimetre-wave spectrometer. Of the three species, only NBD was previously studied at high resolution in the microwave domain. From the present measurements, the derived spectroscopic constants enable prediction of the spectra of all three species at various rotational temperatures (up to 300 K) in the spectral range mapped at high resolution by current radio observatories. Unsuccessful searches for these molecules were conducted toward TMC-1 using the QUIJOTE survey, carried out at the Yebes telescope, allowing derivation of the upper limits to the column densities of 1.6 × 1014 cm-2, 4.9 × 1010 cm-2, and 2.9 × 1010 cm-2 for NBD, CN-NBD, and DCN-NBD, respectively. Using CN-NBD and cyano-indene as proxies for the corresponding bare hydrocarbons, this indicates that-if present in TMC-1-NBD would be at least four times less abundant than indene.


Evidence for an active rare biosphere within freshwater protists community.
Studies on the active rare biosphere at the RNA level are mainly focused on Bacteria and Archaea and fail to include the protists, which are involved in the main biogeochemical cycles of the earth. In this study, the richness, composition and activity of the rare protistan biosphere were determined from a temporal survey of two lakes by pyrosequencing. In these ecosystems, the always rare OTUs represented 77.2% of the total OTUs and 76.6% of the phylogenetic diversity. From the various phylogenetic indices computed, the phylogenetic units (PUs) constituted exclusively by always rare OTUs were discriminated from the other PUs. Therefore, the rare biosphere included mainly taxa that are distant from the reference databases compared to the dominant ones. In addition, the rarest OTUs represented 59.8% of the active biosphere depicted by rRNA and the activity (rRNA:rDNA ratio) increased with the rarity. The high rRNA:rDNA ratio determined in the rare fraction highlights that some protists were active at low abundances and contribute to ecosystem functioning. Interestingly, the always rare and active OTUs were characterized by seasonal changes in relation with the main environmental parameters measured. In conclusion, the rare eukaryotes represent an active, dynamic and overlooked fraction in the lacustrine ecosystems.


Characterization of rheological and mucoadhesive properties of three grades of chitosan hydrochloride.
In the present study the rheological and mucoadhesive properties of three viscosity grades of a cationic polymer, chitosan, were investigated to assess the suitability of this polymer for gastroadhesive formulations. The influence of the pH, ionic strength and temperature of the hydration medium on the rheological properties was studied. The mucoadhesive performance was assessed in vitro by means of rheological synergism and tensile stress testing. A correlation was found between rheological synergism and tensile parameters (force of detachment and work of adhesion), which proves that both methods can correctly predict the mucoadhesive performance of the polymers examined. It was found that the interaction of chitosan with mucin decreases on increasing molecular weight.


Computerized Tomography Scanning and Magnetic Resonance Imaging Will Terminate the Era of the Autopsy - A Hypothesis.
Reports on a marked reduction of the number of autopsies performed worldwide to less than 5% of hospital deaths remain without a satisfactory explanation. The premature disappearance of the autopsy might represent a medical tragedy of a major order. One of the causes for the decrease in autopsies is poorly documented: we suspect that the attending physician might show some reluctance when requesting a consent for an autopsy from the bereaved family. Moreover, this officer might consider that the post mortem will add little information to that already obtained from the computerized tomography scanner or the magnetic resonance imaging. In order to confirm our hypothesis, we carried out a review of 300 articles indexed as "radiologic-histologic correlation", 118 of which were selected for a significant correlation. From the abstracts, we retrieved the type of the article, the degree of correlation as assessed by the authors and the form of imaging employed, and we computed them. The most striking correlation was observed in the small prospective series. An additional search for the "radiologic-autopsy correlation" supported a marked reduction in the number of post-mortems, especially those related with prospective studies. Based on the present study, we cannot determine precisely the role of the house officer in this tragedy. We may have demonstrated, however, that the modern radiologic methods have not yet reached a high enough performance quality to achieve the status of a candidate substitute for the autopsy.


Circadian clocks in antennal neurons are necessary and sufficient for olfaction rhythms in Drosophila.
The Drosophila circadian clock is controlled by interlocked transcriptional feedback loops that operate in many neuronal and nonneuronal tissues. These clocks are roughly divided into a central clock, which resides in the brain and is known to control rhythms in locomotor activity, and peripheral clocks, which comprise all other clock tissues and are thought to control other rhythmic outputs. We previously showed that peripheral oscillators are required to mediate rhythmic olfactory responses in the antenna, but the identity and relative autonomy of these peripheral oscillators has not been defined. Targeted ablation of lateral neurons by using apoptosis-promoting factors and targeted clock disruption in antennal neurons with newly developed dominant-negative versions of CLOCK and CYCLE show that antennal neurons, but not central clock cells, are necessary for olfactory rhythms. Targeted rescue of antennal neuron oscillators in cyc(01) flies through wild-type CYCLE shows that these neurons are also sufficient for olfaction rhythms. Antennal neurons are both necessary and sufficient for olfaction rhythms, which demonstrates for the first time that a peripheral tissue can function as an autonomous pacemaker in Drosophila. These results reveal fundamental differences in the function and organization of circadian oscillators in Drosophila and mammals and suggest that components of the olfactory signal transduction cascade could be targets of circadian regulation.


Susceptibility of Rickettsia rickettsii to Tigecycline in a Cell Culture Assay and Animal Model for Rocky Mountain Spotted Fever.
Rocky Mountain spotted fever (RMSF), caused by Rickettsia rickettsii, is a severe tick-borne infection endemic to the Americas. Oral doxycycline is effective, but during severe life-threatening disease, intravenous therapy is recommended. Unfortunately, intravenous formulations of doxycycline are not always available. Therefore, we aimed to determine the susceptibility of R. rickettsii to an alternative parenteral agent, tigecycline, in vitro and in vivo. To determine the minimum inhibitory concentration of tigecycline, R. rickettsii-inoculated Vero cells were incubated with medium containing tigecycline. At various time points, monolayers were collected and R. rickettsii was quantified via real-time polymerase chain reaction (PCR). The growth of R. rickettsii was inhibited in the presence of ≥ 0.5 µg/mL of tigecycline. To determine the effectiveness of tigecycline in vivo, guinea pigs were inoculated with R. rickettsii. Five days after inoculation, they were treated twice daily with subcutaneous tigecycline 3.75 mg/kg or subcutaneous doxycycline 5 mg/kg. Treated animals improved, whereas untreated controls remained ill. Tissues were collected for quantitative PCR-determined bacterial loads on day 8. Median bacterial loads in the tigecycline group were less than those in untreated animals: liver (0 versus 2.9 × 104 copies/mg), lung (0 versus 8.3 × 103 copies/mg), skin (2.6 × 102 versus 2.2 × 105 copies/mg), spleen (0 versus 1.3 × 104 copies/mg), and testes (0 versus 1.0 × 105 copies/mg, respectively). There were no significant differences in the bacterial loads between doxycycline-treated versus tigecycline-treated guinea pigs. These data indicate that tigecycline is effective against R. rickettsii in cell culture and in an animal model of RMSF.