Assessment of the risks posed by severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) on surfaces requires data on survival of this virus on environmental surfaces and on how survival is affected by environmental variables, such as air temperature (AT) and relative humidity (RH). The use of surrogate viruses has the potential to overcome the challenges of working with SARS-CoV and to increase the available data on coronavirus survival on surfaces. Two potential surrogates were evaluated in this study; transmissible gastroenteritis virus (TGEV) and mouse hepatitis virus (MHV) were used to determine effects of AT and RH on the survival of coronaviruses on stainless steel. At 4°C, infectious virus persisted for as long as 28 days, and the lowest level of inactivation occurred at 20% RH. Inactivation was more rapid at 20°C than at 4°C at all humidity levels; the viruses persisted for 5 to 28 days, and the slowest inactivation occurred at low RH. Both viruses were inactivated more rapidly at 40°C than at 20°C. The relationship between inactivation and RH was not monotonic, and there was greater survival or a greater protective effect at low RH (20%) and high RH (80%) than at moderate RH (50%). There was also evidence of an interaction between AT and RH. The results show that when high numbers of viruses are deposited, TGEV and MHV may survive for days on surfaces at ATs and RHs typical of indoor environments. TGEV and MHV could serve as conservative surrogates for modeling exposure, the risk of transmission, and control measures for pathogenic enveloped viruses, such as SARS-CoV and influenza virus, on health care surfaces.Environmental surfaces have been recognized as likely contributors to the transmission of nosocomial viral infections (25). The question of whether hospital surfaces play a role in the spread of nosocomial viral infection took on particular urgency during the worldwide outbreak of severe acute respiratory syndrome (SARS). SARS was a novel coronavirus infection, and local and institutional outbreaks were driven in part by nosocomial spread; cases of SARS were documented in health care workers, patients, and visitors in health care facilities (20). During outbreaks in health care facilities, surface sampling for SARS coronavirus (SARS-CoV) revealed SARS-CoV nucleic acids on surfaces and inanimate objects (6, 10). This suggests that surfaces could be sources of virus transmission. Assessment of the risk posed by SARS-CoV on surfaces requires data on the survival of the virus on environmental surfaces and data on how this survival is affected by environmental variables, such as air temperature (AT) and relative humidity (RH).Because working with SARS-CoV requires specially trained personnel working under biosafety level 3 (BSL-3) laboratory containment conditions, there are significant challenges in studying this virus, and only limited data on its survival and response to environmental stressors are available. The use of surrogate coronaviruses has the potential to overcome these challenges...

Purpose We aimed to evaluate the efficacy and safety of temperature‐controlled intraductal radiofrequency ablation (ID‐RFA) for advanced malignant hilar biliary obstruction (MHBO). Methods Patients were randomly assigned to RFA group (ID‐RFA and bilateral plastic stent [PS]) or non‐RFA group (bilateral PS) at a 1:1 ratio. Exchange to self‐expanding metal stent (SEMS) was performed after 3 months or when premature PS occlusion occurred. Total event‐free stent patency, overall survival (OS), and adverse events (AEs) were analyzed. Results A total of 30 patients from three hospitals were enrolled. Stent patency and OS did not differ between the two groups (178 days vs 122 days, P = .154; 230 days vs 144 days, P = .643; respectively). In patients with each stricture length ≥11 mm on both sides, stent patency was longer in the RFA group than in the non‐RFA group (175 days vs 121 days, P = .028). More patients received elective exchange to SEMS without PS occlusion in the RFA group than in the non‐RFA group (69.2% vs 23.1%, P = .018). AE rates did not differ between the two groups. Conclusions Temperature‐controlled ID‐RFA for advanced MHBO was safe and feasible. It could prevent premature PS occlusion within 3 months.

Genome-wide association studies in combination with single-cell genomic atlases can provide insights into the mechanisms of disease-causal genetic variation. However, identification of disease-relevant or trait-relevant cell types, states and trajectories is often hampered by sparsity and noise, particularly in the analysis of single-cell epigenomic data. To overcome these challenges, we present SCAVENGE, a computational algorithm that uses network propagation to map causal variants to their relevant cellular context at single-cell resolution. We demonstrate how SCAVENGE can help identify key biological mechanisms underlying human genetic variation, applying the method to blood traits at distinct stages of human hematopoiesis, to monocyte subsets that increase the risk for severe Coronavirus Disease 2019 (COVID-19) and to intermediate lymphocyte developmental states that predispose to acute leukemia. Our approach not only provides a framework for enabling variant-to-function insights at single-cell resolution but also suggests a more general strategy for maximizing the inferences that can be made using single-cell genomic data.

Sulfur bonding interactions between organosulfur compounds and proteins were examined using crystal structures deposited to-date in the PDB. The data was analyzed as a function of sulfur-σ-hole-bonding (i.e., sulfur bonds) to main chain Lewis bases, viz. oxygen and nitrogen atoms of the backbone amide linkages. The analyses also included an examination of sulfur bonding to side chain Lewis bases (O, N, and S) and to the "non-classical" Lewis bases present in electron-rich aromatic amino acids as-well-as to donor-acceptor bond angle distributions. The interactions analyzed included those restricted to the sum of van der Waals radii of the respective atoms or to a distance of 4 Å. The surveyed data revealed that sulfur bonding tendencies (C-S-C bond angles) were impacted not only by steric effects but perhaps also by enthalpic features present in both the donor and acceptor participants. This knowledge is not only of fundamental interest but is also important in terms of materials and drug-design involving moieties incorporating the sulfur atom. Additionally, a new empirical scoring function was developed to address the anisotropy of sulfur in protein-ligand interactions. This newly developed scoring function is incorporated into AutoDock Vina molecular docking program and is valuable for modeling and drug design.

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