Restriction of HIV-1 Escape by a Highly Broad and Potent Neutralizing Antibody.

Broadly neutralizing antibodies (bNAbs) represent a promising approach to prevent and treat HIV-1 infection. However, viral escape through mutation of the HIV-1 envelope glycoprotein (Env) limits clinical applications. Here we describe 1-18, a new VH1-46-encoded CD4 binding site (CD4bs) bNAb with outstanding breadth (97%) and potency (GeoMean IC50 = 0.048 µg/mL). Notably, 1-18 is not susceptible to typical CD4bs escape mutations and effectively overcomes HIV-1 resistance to other CD4bs bNAbs. Moreover, mutational antigenic profiling uncovered restricted pathways of HIV-1 escape. Of most promise for therapeutic use, even 1-18 alone fully suppressed viremia in HIV-1-infected humanized mice without selecting for resistant viral variants. A 2.5-Å cryo-EM structure of a 1-18-BG505SOSIP.664 Env complex revealed that these characteristics are likely facilitated by a heavy-chain insertion and increased inter-protomer contacts. The ability of 1-18 to effectively restrict HIV-1 escape pathways provides a new option to successfully prevent and treat HIV-1 infection.

Multivalent pyrrolidines acting as pharmacological chaperones against Gaucher disease.

A concise asymmetric synthesis of clickable enantiomeric pyrrolidines was achieved using Crabbé-Ma allenation. The synthesized iminosugars were grafted by copper-free strain-promoted alkyne-azide cycloaddition onto phosphorus dendrimers. The hexavalent and dodecavalent pyrrolidines were evaluated as ß-glucocerebrosidase inhibitors. The level of inhibition suggests that monofluorocyclooctatriazole group may contribute to the affinity for the protein leading to potent multivalent inhibitors. Docking studies were carried out to rationalize these results. Then, the iminosugars clusters were evaluated as pharmacological chaperones in Gaucher patients' fibroblasts. An increase in ß-glucocerebrosidase activity was observed with hexavalent and dodecavalent pyrrolidines at concentrations as low as 1 µM and 0.1 µM, respectively. These iminosugar clusters constitute the first example of multivalent pyrrolidines acting as pharmacological chaperones against Gaucher disease.

Methods for health workforce projection model: systematic review and recommended good practice reporting guideline.

BACKGROUND: Health workforce projection models are integral components of a robust healthcare system. This research aims to review recent advancements in methodology and approaches for health workforce projection models and proposes a set of good practice reporting guidelines. METHODS: We conducted a systematic review by searching medical and social science databases, including PubMed, EMBASE, Scopus, and EconLit, covering the period from 2010 to 2023. The inclusion criteria encompassed studies projecting the demand for and supply of the health workforce. PROSPERO registration: CRD 42023407858. RESULTS: Our review identified 40 relevant studies, including 39 single countries analysis (in Australia, Canada, Germany, Ghana, Guinea, Ireland, Jamaica, Japan, Kazakhstan, Korea, Lesotho, Malawi, New Zealand, Portugal, Saudi Arabia, Serbia, Singapore, Spain, Thailand, UK, United States), and one multiple country analysis (in 32 OECD countries). Recent studies have increasingly embraced a complex systems approach in health workforce modelling, incorporating demand, supply, and demand-supply gap analyses. The review identified at least eight distinct types of health workforce projection models commonly used in recent literature: population-to-provider ratio models (n = 7), utilization models (n = 10), needs-based models (n = 25), skill-mixed models (n = 5), stock-and-flow models (n = 40), agent-based simulation models (n = 3), system dynamic models (n = 7), and budgetary models (n = 5). Each model has unique assumptions, strengths, and limitations, with practitioners often combining these models. Furthermore, we found seven statistical approaches used in health workforce projection models: arithmetic calculation, optimization, time-series analysis, econometrics regression modelling, microsimulation, cohort-based simulation, and feedback causal loop analysis. Workforce projection often relies on imperfect data with limited granularity at the local level. Existing studies lack standardization in reporting their methods. In response, we propose a good practice reporting guideline for health workforce projection models designed to accommodate various model types, emerging methodologies, and increased utilization of advanced statistical techniques to address uncertainties and data requirements. CONCLUSIONS: This study underscores the significance of dynamic, multi-professional, team-based, refined demand, supply, and budget impact analyses supported by robust health workforce data intelligence. The suggested best-practice reporting guidelines aim to assist researchers who publish health workforce studies in peer-reviewed journals. Nevertheless, it is expected that these reporting standards will prove valuable for analysts when designing their own analysis, encouraging a more comprehensive and transparent approach to health workforce projection modelling.

Tone management: An environmental scan of current management practices across Canada.

BACKGROUND: Currently, there are no standardized approaches to care or evaluation for tone dysfunction in Canada. The study authors hypothesize that there is significant practice variation across the country. This environmental scan is aimed to describe the current practice for management of paediatric patients with hypertonia across Canada. METHODS: A web-based survey was developed by the authors with a multi-disciplinary approach and sent to representative paediatric rehabilitation sites in each province in Canada. Disciplines at the rehabilitation sites surveyed included all or some of the following disciplines: physiatry, neurology, neurosurgery, plastic surgery, orthopaedic surgery, physiotherapy and occupational therapy. All statistical analyses were performed using the R statistical software version 4.0. Fifteen rehabilitation sites were contacted, and 12 sites were used for the final analysis. RESULTS: Cerebral palsy was found to be the most common diagnosis for tone dysfunction, with 58% of sites diagnosing greater than 20 new patients per year. In 67% of sites, patients were seen within a formal multidisciplinary clinic to manage hypertonia. All 12 sites utilized oral baclofen and gabapentin, and 92% of sites utilized trihexyphenidyl. Botulinum toxin injections were offered at 50% of sites. Upper and lower extremity surgical procedures were offered in 83% of the sites. CONCLUSION: The information gained from this study provides some insight into the current practice across Canada for children with hypertonia. This study may assist in the development of a national, standardized strategy to tone management, potentially facilitating more equitable access to care for patients.

Phosphorus Dendrimers for Metal-Free Ligation: Design of Multivalent Pharmacological Chaperones against Gaucher Disease.

The first phosphorus dendrimers built on a cyclotriphosphazene core and decorated with six or twelve monofluorocyclooctyne units were prepared. A simple stirring allowed the grafting of N-hexyl deoxynojirimycin inhitopes onto their surface by copper-free strain promoted alkyne-azide cycloaddition click reaction. The synthesized iminosugars clusters were tested as multivalent inhibitors of the biologically relevant enzymes ß-glucocerebrosidase and acid α-glucosidase, involved in Gaucher and Pompe lysosomal storage diseases, respectively. For both enzymes, all the multivalent compounds were more potent than the reference N-hexyl deoxynojirimycin. Remarkably, the final dodecavalent compound proved to be one of the best ß-glucocerebrosidase inhibitors described to date. These cyclotriphosphazene-based deoxynojirimycin dendrimers were then evaluated as pharmacological chaperones against Gaucher disease. Not only did these multivalent constructs cross the cell membranes but they were also able to increase ß-glucocerebrosidase activity in Gaucher cells. Notably, dodecavalent compound allowed a 1.4-fold enzyme activity enhancement at a concentration as low as 100 nM. These new monofluorocyclooctyne-presenting dendrimers may further find numerous applications in the synthesis of multivalent objects for biological and pharmacological purposes.

Amyloidogenic Processing of Amyloid Precursor Protein Drives Stretch-Induced Disruption of Axonal Transport in hiPSC-Derived Neurons.

Traumatic brain injury (TBI) results in disrupted brain function following impact from an external force and is a risk factor for sporadic Alzheimer's disease (AD). Although neurologic symptoms triggered by mild traumatic brain injuries (mTBI), the most common form of TBI, typically resolve rapidly, even an isolated mTBI event can increase the risk to develop AD. Aberrant accumulation of amyloid ß peptide (Aß), a cleaved fragment of amyloid precursor protein (APP), is a key pathologic outcome designating the progression of AD following mTBI and has also been linked to impaired axonal transport. However, relationships among mTBI, amyloidogenesis, and axonal transport remain unclear, in part because of the dearth of human models to study the neuronal response following mTBI. Here, we implemented a custom-microfabricated device to deform neurons derived from human-induced pluripotent stem cells, derived from a cognitively unimpaired male individual, to mimic the mild stretch experienced by neurons during mTBI. Although no cell lethality or cytoskeletal disruptions were observed, mild stretch was sufficient to stimulate rapid amyloidogenic processing of APP. This processing led to abrupt cessation of APP axonal transport and progressive formation of aberrant axonal accumulations that contained APP, its processing machinery, and amyloidogenic fragments. Consistent with this sequence of events, stretch-induced defects were abrogated by reducing amyloidogenesis either pharmacologically or genetically. In sum, we have uncovered a novel and manipulable stretch-induced amyloidogenic pathway directly responsible for APP axonal transport dysregulation. Our findings may help to understand and ultimately mitigate the risk of developing AD following mTBI.SIGNIFICANCE STATEMENT Mild traumatic brain injury is a risk factor for sporadic Alzheimer's disease (AD). Increased amyloid ß peptide generation after injury may drive this risk. Here, by using a custom-built device to impose mild stretch to human neurons, we found that stretch triggers amyloid precursor protein (APP) cleavage, and thus amyloid ß peptide generation, consequently disrupting APP axonal transport. Compellingly, protecting APP from cleavage was sufficient to spare axonal transport dysregulation and the consequent aberrant axonal accumulation of APP. Supporting such protective mechanism, the expression of the AD-protective APPA673T genetic variant conferred protection against stretch-induced APP axonal transport phenotypes. Our data reveal potential subcellular pathways contributing to the development of AD-associated phenotypes following mild traumatic brain injury, and putative strategies for intervening in these pathways.

Cell therapy attenuates endothelial dysfunction in hypertensive rats with heart failure and preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is defined by increased left ventricular (LV) stiffness, impaired vascular compliance, and fibrosis. Although systemic inflammation, driven by comorbidities, has been proposed to play a key role, the precise pathogenesis remains elusive. To test the hypothesis that inflammation drives endothelial dysfunction in HFpEF, we used cardiosphere-derived cells (CDCs), which reduce inflammation and fibrosis, improving function, structure, and survival in HFpEF rats. Dahl salt-sensitive rats fed a high-salt diet developed HFpEF, as manifested by diastolic dysfunction, systemic inflammation, and accelerated mortality. Rats were randomly allocated to receive intracoronary infusion of CDCs or vehicle. Two weeks later, inflammation, oxidative stress, and endothelial function were analyzed. Single-cell RNA sequencing of heart tissue was used to assay transcriptomic changes. CDCs improved endothelial-dependent vasodilation while reducing oxidative stress and restoring endothelial nitric oxide synthase (eNOS) expression. RNA sequencing revealed CDC-induced attenuation of pathways underlying endothelial cell leukocyte binding and innate immunity. Exposure of endothelial cells to CDC-secreted extracellular vesicles in vitro reduced VCAM-1 protein expression and attenuated monocyte adhesion and transmigration. Cell therapy with CDCs corrects diastolic dysfunction, reduces oxidative stress, and restores vascular reactivity. These findings lend credence to the hypothesis that inflammatory changes of the vascular endothelium are important, if not central, to HFpEF pathogenesis.NEW & NOTEWORTHY We tested the concept that inflammation of endothelial cells is a major pathogenic factor in HFpEF. CDCs are heart-derived cell products with verified anti-inflammatory therapeutic properties. Infusion of CDCs reduced oxidative stress, restored eNOS abundance, lowered monocyte levels, and rescued the expression of multiple disease-associated genes, thereby restoring vascular reactivity. The salutary effects of CDCs support the hypothesis that inflammation of endothelial cells is a proximate driver of HFpEF.

Catalytic Enantioselective Birch-Heck Sequence for the Synthesis of Phenanthridinone Derivatives with an All-Carbon Quaternary Stereocenter.

Novel phenanthridinone analogues with an all-carbon quaternary stereocenter have been enantioselectively synthesized using the Birch-Heck sequence. Flat phenanthridinone structures have extensive bioactivity but consequently also suffer from poor therapeutic selectivity. The addition of a quaternary center to the phenanthridinone skeleton has the potential to generate more complex analogues with improved selectivity. Unfortunately, no general synthetic pathway to such derivatives exists. Herein we report a four-step process that transforms inexpensive benzoic acid into 22 different quaternary carbon-containing phenanthridinone analogues with a variety of substituents on all three rings: alkyl groups at the quaternary center; methyl, methoxymethyl, or para-methoxybenzyl on the amide nitrogen; and halogen and methyl substituents on the aryl ring. Good to very good enantioselectivity was demonstrated in the key intramolecular desymmetrizing Mizoroki-Heck reaction. Transformations of the Heck reaction products into molecules with potentially greater therapeutic relevance were also accomplished.

Genetic potential for changes in breeding systems: Predicted and observed trait changes during artificial selection for male and female allocation in a gynodioecious species.

PREMISE: Evolution of separate sexes from hermaphroditism often proceeds through gynodioecy, but genetic constraints on this process are poorly understood. Genetic (co-)variances and between-sex genetic correlations were used to predict evolutionary responses of multiple reproductive traits in a sexually dimorphic gynodioecious species, and predictions were compared with observed responses to artificial selection. METHODS: Schiedea (Caryophyllaceae) is an endemic Hawaiian lineage with hermaphroditic, gynodioecious, subdioecious, and dioecious species. We measured genetic parameters of Schiedea salicaria and used them to predict evolutionary responses of 18 traits in hermaphrodites and females in response to artificial selection for increased male (stamen) biomass in hermaphrodites or increased female (carpel, capsule) biomass in females. Observed responses over two generations were compared with predictions in replicate lines of treatments and controls. RESULTS: In only two generations, both stamen biomass in hermaphrodites and female biomass in females responded markedly to direct selection, supporting a key assumption of models for evolution of dioecy. Other biomass traits, pollen and ovule numbers, and inflorescence characters important in wind pollination evolved indirectly in response to selection on sex allocation. Responses generally followed predictions from multivariate selection models, with some responses unexpectedly large due to increased genetic correlations as selection proceeded. CONCLUSIONS: Results illustrate the power of artificial selection and utility of multivariate selection models incorporating sex differences. They further indicate that pollen and ovule numbers and inflorescence architecture could evolve in response to selection on biomass allocation to male versus female function, producing complex changes in plant phenotype as separate sexes evolve.

The First 100 Days of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Control in Vietnam.

BACKGROUND: One hundred days after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first reported in Vietnam on 23 January, 270 cases were confirmed, with no deaths. We describe the control measures used by the government and their relationship with imported and domestically acquired case numbers, with the aim of identifying the measures associated with successful SARS-CoV-2 control. METHODS: Clinical and demographic data on the first 270 SARS-CoV-2 infected cases and the timing and nature of government control measures, including numbers of tests and quarantined individuals, were analyzed. Apple and Google mobility data provided proxies for population movement. Serial intervals were calculated from 33 infector-infectee pairs and used to estimate the proportion of presymptomatic transmission events and time-varying reproduction numbers. RESULTS: A national lockdown was implemented between 1 and 22 April. Around 200 000 people were quarantined and 266 122 reverse transcription polymerase chain reaction (RT-PCR) tests conducted. Population mobility decreased progressively before lockdown. In total, 60% (163/270) of cases were imported; 43% (89/208) of resolved infections remained asymptomatic for the duration of infection. The serial interval was 3.24 days, and 27.5% (95% confidence interval [CI], 15.7%-40.0%) of transmissions occurred presymptomatically. Limited transmission amounted to a maximum reproduction number of 1.15 (95% CI, .·37-2.·36). No community transmission has been detected since 15 April. CONCLUSIONS: Vietnam has controlled SARS-CoV-2 spread through the early introduction of mass communication, meticulous contact tracing with strict quarantine, and international travel restrictions. The value of these interventions is supported by the high proportion of asymptomatic and imported cases, and evidence for substantial presymptomatic transmission.

Viral Metagenomic Analysis of Cerebrospinal Fluid from Patients with Acute Central Nervous System Infections of Unknown Origin, Vietnam.

Central nervous system (CNS) infection is a serious neurologic condition, although the etiology remains unknown in >50% of patients. We used metagenomic next-generation sequencing to detect viruses in 204 cerebrospinal fluid (CSF) samples from patients with acute CNS infection who were enrolled from Vietnam hospitals during 2012-2016. We detected 8 viral species in 107/204 (52.4%) of CSF samples. After virus-specific PCR confirmation, the detection rate was lowered to 30/204 (14.7%). Enteroviruses were the most common viruses detected (n = 23), followed by hepatitis B virus (3), HIV (2), molluscum contagiosum virus (1), and gemycircularvirus (1). Analysis of enterovirus sequences revealed the predominance of echovirus 30 (9). Phylogenetically, the echovirus 30 strains belonged to genogroup V and VIIb. Our results expanded knowledge about the clinical burden of enterovirus in Vietnam and underscore the challenges of identifying a plausible viral pathogen in CSF of patients with CNS infections.

Pharmacological Chaperone Therapy for Pompe Disease.

Pompe disease (PD), a lysosomal storage disease, is caused by mutations of the GAA gene, inducing deficiency in the acid alpha-glucosidase (GAA). This enzymatic impairment causes glycogen burden in lysosomes and triggers cell malfunctions, especially in cardiac, smooth and skeletal muscle cells and motor neurons. To date, the only approved treatment available for PD is enzyme replacement therapy (ERT) consisting of intravenous administration of rhGAA. The limitations of ERT have motivated the investigation of new therapies. Pharmacological chaperone (PC) therapy aims at restoring enzymatic activity through protein stabilization by ligand binding. PCs are divided into two classes: active site-specific chaperones (ASSCs) and the non-inhibitory PCs. In this review, we summarize the different pharmacological chaperones reported against PD by specifying their PC class and activity. An emphasis is placed on the recent use of these chaperones in combination with ERT.

Concise asymmetric synthesis of new enantiomeric C-alkyl pyrrolidines acting as pharmacological chaperones against Gaucher disease.

A concise and asymmetric synthesis of the enantiomeric pyrrolidines 2 and ent-2 are herein reported. Both enantiomers were assessed as ß-GCase inhibitors. While compound ent-2 acted as a poor competitive inhibitor, its enantiomer 2 proved to be a potent non-competitive inhibitor. Docking studies were carried out to substantiate their respective protein binding mode. Both pyrrolidines were also able to enhance lysosomal ß-GCase residual activity in N370S homozygous Gaucher fibroblasts. Notably, the non-competitive inhibitor 2 displayed an enzyme activity enhancement comparable to that of reference compounds IFG and NN-DNJ. This work highlights the impact of inhibitors chirality on their protein binding mode and shows that, beyond competitive inhibitors, the study of non-competitive ones can lead to the identification of new relevant parmacological chaperones.

Second-Generation Pharmacological Chaperones: Beyond Inhibitors.

Protein misfolding induced by missense mutations is the source of hundreds of conformational diseases. The cell quality control may eliminate nascent misfolded proteins, such as enzymes, and a pathological loss-of-function may result from their early degradation. Since the proof of concept in the 2000s, the bioinspired pharmacological chaperone therapy became a relevant low-molecular-weight compound strategy against conformational diseases. The first-generation pharmacological chaperones were competitive inhibitors of mutant enzymes. Counterintuitively, in binding to the active site, these inhibitors stabilize the proper folding of the mutated protein and partially rescue its cellular function. The main limitation of the first-generation pharmacological chaperones lies in the balance between enzyme activity enhancement and inhibition. Recent research efforts were directed towards the development of promising second-generation pharmacological chaperones. These non-inhibitory ligands, targeting previously unknown binding pockets, limit the risk of adverse enzymatic inhibition. Their pharmacophore identification is however challenging and likely requires a massive screening-based approach. This review focuses on second-generation chaperones designed to restore the cellular activity of misfolded enzymes. It intends to highlight, for a selected set of rare inherited metabolic disorders, the strategies implemented to identify and develop these pharmacologically relevant small organic molecules as potential drug candidates.

Dengue-Associated Posterior Reversible Encephalopathy Syndrome, Vietnam.

Dengue can cause neurologic complications in addition to the more common manifestations of plasma leakage and coagulopathy. Posterior reversible encephalopathy syndrome has rarely been described in dengue, although the pathophysiology of endothelial dysfunction likely underlies both. We describe a case of dengue-associated posterior reversible encephalopathy syndrome and discuss diagnosis and management.

A universal genome sequencing method for rotavirus A from human fecal samples which identifies segment reassortment and multi-genotype mixed infection.

BACKGROUND: Genomic characterization of rotavirus (RoV) has not been adopted at large-scale due to the complexity of obtaining sequences for all 11 segments, particularly when feces are used as starting material. METHODS: To overcome these limitations, we developed a novel RoV capture and genome sequencing method combining commercial enzyme immunoassay plates and a set of routinely used reagents. RESULTS: Our approach had a 100% success rate, producing >90% genome coverage for diverse RoV present in fecal samples (Ct < 30). CONCLUSIONS: This method provides a novel, reproducible and comparatively simple approach for genomic RoV characterization and could be scaled-up for use in global RoV surveillance systems. TRIAL REGISTRATION (PROSPECTIVELY REGISTERED): Current Controlled Trials ISRCTN88101063 . Date of registration: 14/06/2012.

Nicotinic receptor activation augments muscarinic receptor-mediated eccrine sweating but not cutaneous vasodilatation in young males.

NEW FINDINGS: What is the central question of this study? Acetylcholine released from cholinergic nerves can activate both muscarinic and nicotinic receptors. Although each receptor can independently induce cutaneous vasodilatation and eccrine sweating, it remains to be elucidated whether the two receptors interact in order to mediate these responses. What is the main finding and its importance? We show that although nicotinic receptor activation does not modulate muscarinic cutaneous vasodilatation, it lowers the muscarinic receptor agonist threshold at which onset for eccrine sweating (augmentation of muscarinic eccrine sweating) occurs in young men in normothermic resting conditions. These results provide new insights into the physiological significance of nicotinic receptors in the regulation of cutaneous perfusion and eccrine sweating. Acetylcholine released from cholinergic nerves can activate both muscarinic and nicotinic receptors; each is known independently to induce cutaneous vasodilatation and eccrine sweating in humans. However, it is not known whether the two receptors interact in order to mediate cutaneous vasodilatation and eccrine sweating. In 10 young men (27 ± 6 years old), cutaneous vascular conductance and sweat rate were evaluated at intradermal microdialysis sites that were continuously perfused with either lactated Ringer's solution (control) or three different concentrations of nicotine (0.1, 1 and 10 mm), a nicotinic receptor agonist. Co-administration of methacholine, a muscarinic receptor agonist, was performed at all skin sites in a dose-proportional fashion (0.0125, 0.25, 5, 100 and 2000 mm, each for 25 min). Administration of nicotine alone caused dose-dependent transient increases in cutaneous vascular conductance and sweat rate (all P ≤ 0.05), which thereafter returned to pre-nicotine levels, except that a portion of transient responses remained with continuous administration of 10 mm nicotine (both P ≤ 0.05). Cutaneous vascular conductance was increased by administration of ≥0.25 mm methacholine at the control site, and this response was likewise observed in the presence of co-administration of all doses of nicotine used (all P ≤ 0.05). Sweat rate at the control site was increased by administration of ≥0.25 mm methacholine, but the lowest dose of methacholine (0.0125 mm) was able to increase sweat rate in the presence of 10 mm nicotine (P ≤ 0.05). We conclude that nicotinic receptor activation lowers the muscarinic receptor agonist threshold for eccrine sweating (augmentation of muscarinic sweating) but does not affect muscarinic cutaneous vasodilatation in young men in normothermic resting conditions.

Evaluation of Luminex xTAG Gastrointestinal Pathogen Panel Assay for Detection of Multiple Diarrheal Pathogens in Fecal Samples in Vietnam.

Diarrheal disease is a complex syndrome that remains a leading cause of global childhood morbidity and mortality. The diagnosis of enteric pathogens in a timely and precise manner is important for making treatment decisions and informing public health policy, but accurate diagnosis is a major challenge in industrializing countries. Multiplex molecular diagnostic techniques may represent a significant improvement over classical approaches. We evaluated the Luminex xTAG gastrointestinal pathogen panel (GPP) assay for the detection of common enteric bacterial and viral pathogens in Vietnam. Microbiological culture and real-time PCR were used as gold standards. The tests were performed on 479 stool samples collected from people admitted to the hospital for diarrheal disease throughout Vietnam. Sensitivity and specificity were calculated for the xTAG GPP for the seven principal diarrheal etiologies. The sensitivity and specificity for the xTAG GPP were >88% for Shigellaspp.,Campylobacterspp., rotavirus, norovirus genotype 1/2 (GI/GII), and adenovirus compared to those of microbiological culture and/or real-time PCR. However, the specificity was low (∼60%) for Salmonella species. Additionally, a number of important pathogens that are not identified in routine hospital procedures in this setting, such as Cryptosporidiumspp. and Clostridium difficile, were detected with the GPP. The use of the Luminex xTAG GPP for the detection of enteric pathogens in settings, like Vietnam, would dramatically improve the diagnostic accuracy and capacity of hospital laboratories, allowing for timely and appropriate therapy decisions and a wider understanding of the epidemiology of pathogens associated with severe diarrheal disease in low-resource settings.

K+ channel mechanisms underlying cholinergic cutaneous vasodilation and sweating in young humans: roles of KCa, KATP, and KV channels?

Acetylcholine released from cholinergic nerves is involved in heat loss responses of cutaneous vasodilation and sweating. K(+) channels are thought to play a role in regulating cholinergic cutaneous vasodilation and sweating, though which K(+) channels are involved in their regulation remains unclear. We evaluated the hypotheses that 1) Ca(2+)-activated K(+) (KCa), ATP-sensitive K(+) (KATP), and voltage-gated K(+) (KV) channels all contribute to cholinergic cutaneous vasodilation; and 2) KV channels, but not KCa and KATP channels, contribute to cholinergic sweating. In 13 young adults (24 ± 5 years), cutaneous vascular conductance (CVC) and sweat rate were evaluated at intradermal microdialysis sites that were continuously perfused with: 1) lactated Ringer (Control), 2) 50 mM tetraethylammonium (KCa channel blocker), 3) 5 mM glybenclamide (KATP channel blocker), and 4) 10 mM 4-aminopyridine (KV channel blocker). At all sites, cholinergic cutaneous vasodilation and sweating were induced by coadministration of methacholine (0.0125, 0.25, 5, 100, and 2,000 mM, each for 25 min). The methacholine-induced increase in CVC was lower with the KCa channel blocker relative to Control at 0.0125 (1 ± 1 vs. 9 ± 6%max) and 5 (2 ± 5 vs. 17 ± 14%max) mM methacholine, whereas it was lower in the presence of KATP (69 ± 7%max) and KV (57 ± 14%max) channel blocker compared with Control (79 ± 6%max) at 100 mM methacholine. Furthermore, methacholine-induced sweating was lower at the KV channel blocker site (0.42 ± 0.17 mg·min(-1)·cm(-2)) compared with Control (0.58 ± 0.15 mg·min(-1)·cm(-2)) at 2,000 mM methacholine. In conclusion, we show that KCa, KATP, and KV channels play a role in cholinergic cutaneous vasodilation, whereas only KV channels contribute to cholinergic sweating in normothermic resting humans.