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81.
Bagaza virus (BAGV), a member of the Ntaya serogroup in the Flavivirus genus of the Flaviviridae, was isolated from the brain tissue of a Himalayan monal pheasant that died following neurological signs in Pretoria, South Africa in 2016. Next-generation sequencing was carried out on this isolate resulting in a genome sequence of 10980nt. The full genome sequence of this isolate, designated ZRU96-16, shared 98% nucleotide identity with a BAGV isolate found in Culex univitattus mosquitoes from Namibia and 97% nucleotide identity with a Spanish BAGV sequence isolated from an infected partridge. In total, seven amino acid variations were unique to ZRU96-16 after alignment with other BAGV and Israel turkey meningoencephalomyelitis (ITV) genomes. The 3′UTR sequence of ZRU96-16 was resolved with sufficient detail to be able to annotate the variable and conserved sequence elements within this region. Multiple sequence alignment of the 3′UTR suggested that it could be useful in lineage designation as more similar viruses carried similar mutations across this region, while also retaining certain unique sites. Maximum likelihood phylogenetic analysis revealed two clusters containing both BAGV and ITVs from Europe, the Middle East and Africa. Broadly, temporal clustering separated isolates into two groups, with one cluster representing viruses from the 1960–2000’s and the other from 2010 onwards. This suggests that there is consistent exchange of BAGV and ITV between Europe and Africa. This investigation provides more information on the phylogenetics of an under-represented member of the Flaviviridae and provides an avenue for more extensive research on its pathogenesis and geographic expansion.  相似文献   
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Several inflammatory cytokines that promote inflammation and pathogenesis in asthma signal through the Janus kinase 1 (JAK1) pathway. This phase I, randomized, placebo‐controlled trial assessed the pharmacokinetics and safety of single and multiple ascending doses up to 15 mg twice daily for 14 days of a JAK1 inhibitor, GDC‐0214, in healthy volunteers (HVs; n = 66). Doses were administered with a dry powder, capsule‐based inhaler. An accompanying open‐label gamma scintigraphy study in HVs examined the lung deposition of a single dose of inhaled Technetium‐99m (99mTc)‐radiolabeled GDC‐0214. GDC‐0214 plasma concentrations were linear and approximately dose‐proportional after both single and multiple doses. Peak plasma concentrations occurred at 15–30 min after dosing. The mean apparent elimination half‐life ranged from 32 to 56 h across all single and multiple dose cohorts. After single and multiple doses, all adverse events were mild or moderate, and none led to treatment withdrawal. There was no clear evidence of systemic toxicity due to JAK1 inhibition, and systemic exposure was low, with plasma concentrations at least 15‐fold less than the plasma protein binding‐corrected IC50 of JAK1 at the highest dose. Scintigraphy showed that approximately 50% of the emitted dose of radiolabeled GDC‐0214 was deposited in the lungs and was distributed well to the peripheral airways. 99mTc‐radiolabeled GDC‐0214 (1 mg) exhibited a mean plasma Cmax similar to that observed in phase I at the same dose level. Overall, inhaled GDC‐0214 exhibited pharmacokinetic properties favorable for inhaled administration.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Many factors drive asthma pathogenesis, including several cytokines that signal through the Janus kinase 1 (JAK1) pathway. Inhibition of JAK1 is a possible target for asthma treatments, but previous studies show oral JAK1 inhibitors lead to increased risk of severe infections, malignancy and cardiovascular events.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
This study investigated the safety, pharmacokinetics, and lung deposition of GDC‐0214, an inhaled JAK1 inhibitor designed to target the lungs.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Inhaled delivery of a JAK inhibitor for 14 days exhibited low systemic exposure, leading to few adverse events and limited systemic toxicity, while demonstrating high deposition in the lungs.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
Local pulmonary application of JAK inhibitors may be an effective treatment for asthma with limited systemic risks.  相似文献   
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1. The effect of cryopreservation on the metabolic capacity of monkey hepatocytes over 4 h in suspension and 24 h in culture was determined. Hepatocytes were diluted in a buffer containing 10% DMSO and frozen in a computer-controlled chamber. 2. Initial ethoxyresorufin and ethoxycoumarin O  相似文献   
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BackgroundDentists may choose to integrate intraoral scanners (IOSs) into their practices, but there are many different IOS technologies and system generations to choose from, posing a challenge for dentists who want to invest in them.MethodsA survey of IOS use rates, advantages, satisfaction, and training was developed and deployed through Qualtrics to the 968 members of the American Dental Association Clinical Evaluators (ACE) Panel on February 19, 2021. Nonrespondents were sent reminders, and data were analyzed in SAS Version 9.4 (SAS).ResultsA total of 369 panelists responded to the survey. IOS use was split among the ACE Panel; 53% indicated they use one in their practice. The top reason respondents began using IOSs was to improve clinical efficiency (70%). Ninety percent of respondents use IOSs for single tooth-supported crowns, and 58% began using IOSs less than 4 years ago. Most users are at least mostly satisfied (91%) with the results. Among nonusers, the top reason for not using an IOS was the high level of financial investment (66%); 34% and 40% of nonusers are thinking of buying or training with IOSs in 2021, respectively.ConclusionsUptake of IOSs is split; most users are satisfied with their results, and nonusers cited financial barriers as the most common reason for not investing in one.Practical ImplicationsAs IOSs continue to penetrate the market and dentists are faced with a decision whether to invest in one, they will need guidance on how to choose the most appropriate device for their patients.  相似文献   
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Previous studies at an oil refinery in Saint John, New Brunswick, Canada, found a diminished fish community downstream of the effluent outfall that appeared to be associated with periodic low dissolved oxygen concentrations due to episodic discharges of contaminated transport vessel ballast water. This study was initiated after the ballast water was removed from the effluent to further investigate the potential causes of residual effects in the study stream, Little River. We used field caging of fish, laboratory bioassays, and chemical analysis of effluents and sediments from the field site to determine if the effluent or contaminated sediments were affecting the recovery of the fish community in Little River. The field studies suggested that exposed, caged fish were affected, displaying >40 % increases in liver sizes and increased liver detoxification enzyme activity (cytochrome P450 1A, CYP1A); however, similar responses were absent in laboratory exposures that used effluent only. Adding sediments collected from the vicinity of the refinery’s outfall to the laboratory bioassays reproduced some of the field responses. Chemical analyses showed high concentrations of PAHs in sediments but low concentrations in the effluent, suggesting that the PAHs in the sediment were contributing more to the impacts than the effluent. Application of effects-based monitoring is suggested as beneficial to identify impacts to fisheries where refinery effluents of this type are involved.  相似文献   
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