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101.
Bloomfield Laura S. P. Tracey Christopher Mbabazi Edith Schultz Rhiannon L. Henderson Rebecca Bardosh Kevin Randolph Shannon Paige Sarah 《EcoHealth》2022,19(2):299-314
EcoHealth - The majority of emerging and re-emerging infectious diseases in people are zoonotic. Despite substantial research in communities adjacent to protected areas with high levels of... 相似文献
102.
Shannon M. Beston Jeffry L. Dudycha David M. Post Matthew R. Walsh 《Evolution; international journal of organic evolution》2019,73(4):792-802
Variation in eye size is ubiquitous across taxa. Increased eye size is correlated with improved vision and increased fitness via shifts in behavior. Tests of the drivers of eye size evolution have focused on macroevolutionary studies evaluating the importance of light availability. Predator‐induced mortality has recently been identified as a potential driver of eye size variation. Here, we tested the influence of increased predation by the fish predator, the alewife (Alosa pseudoharengus) on eye size evolution in waterfleas (Daphnia ambigua) from lakes in Connecticut. We quantified the relative eye size of Daphnia from lakes with and without alewife using wild‐caught and third‐generation laboratory reared specimens. This includes comparisons between lakes where alewife are present seasonally (anadromous) or permanently (landlocked). Wild‐caught specimens did not differ in eye size across all lakes. However, third‐generation lab reared Daphnia from lakes with alewife, irrespective of the form of alewife predation, exhibited significantly larger eyes than Daphnia from lakes without alewife. This genetically based increase in eye size may enhance the ability of Daphnia to detect predators. Alternatively, such shifts in eye size may be an indirect response to Daphnia aggregating at the bottom of lakes. To test these mechanisms, we collected Daphnia as a function of depth and found that eye size differed in Daphnia found at the surface versus the bottom of the water column between anadromous alewife and no alewife lakes. However, we found no evidence of Daphnia aggregating at the bottom of lakes. Such results indicate that the evolution of a larger eye may be explained by a connection between eyes and enhanced survival. We discuss the cause of the lack of concordance in eye size variation between our phenotypic and genetic specimens and the ultimate drivers of eye size. 相似文献
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106.
Catherine A. Staton Joo Ricardo Nickenig Vissoci Deena El-Gabri Konyinsope Adewumi Tessa Concepcion Shannon A. Elliott Daniel R. Evans Sophie W. Galson Charles T. Pate Lindy M. Reynolds Nadine A. Sanchez Alexandra E. Sutton Charlotte Yuan Alena Pauley Luciano Andrade Megan Von Isenberg Jinny J. Ye Charles J. Gerardo 《PLoS medicine》2022,19(4)
BackgroundDisease and disability from alcohol use disproportionately impact people in low- and middle-income countries (LMICs). While varied interventions have been shown to reduce alcohol use in high-income countries, their efficacy in LMICs has not been assessed. This systematic review describes current published literature on patient-level alcohol interventions in LMICs and specifically describes clinical trials evaluating interventions to reduce alcohol use in LMICs.Methods and findingsIn accordance with PRISMA, we performed a systematic review using an electronic search strategy from January 1, 1995 to December 1, 2020. Title, abstract, as well as full-text screening and extraction were performed in duplicate. A meta-summary was performed on randomized controlled trials (RCTs) that evaluated alcohol-related outcomes. We searched the following electronic databases: PubMed, EMBASE, Scopus, Web of Science, Cochrane, WHO Global Health Library, and PsycINFO. Articles that evaluated patient-level interventions targeting alcohol use and alcohol-related harm in LMICs were eligible for inclusion. No studies were excluded based on language.After screening 5,036 articles, 117 articles fit our inclusion criteria, 75 of which were RCTs. Of these RCTs, 93% were performed in 13 middle-income countries, while 7% were from 2 low-income countries. These RCTs evaluated brief interventions (24, defined as any intervention ranging from advice to counseling, lasting less than 1 hour per session up to 4 sessions), psychotherapy or counseling (15, defined as an interaction with a counselor longer than a brief intervention or that included a psychotherapeutic component), health promotion and education (20, defined as an intervention encouraged individuals’ agency of taking care of their health), or biologic treatments (19, defined as interventions where the biological function of alcohol use disorder (AUD) as the main nexus of intervention) with 3 mixing categories of intervention types. Due to high heterogeneity of intervention types, outcome measures, and follow-up times, we did not conduct meta-analysis to compare and contrast studies, but created a meta-summary of all 75 RCT studies. The most commonly evaluated intervention with the most consistent positive effect was a brief intervention; similarly, motivational interviewing (MI) techniques were most commonly utilized among the diverse array of interventions evaluated.ConclusionsOur review demonstrated numerous patient-level interventions that have the potential to be effective in LMICs, but further research to standardize interventions, populations, and outcome measures is necessary to accurately assess their effectiveness. Brief interventions and MI techniques were the most commonly evaluated and had the most consistent positive effect on alcohol-related outcomes.Trial registrationProtocol Registry: PROSPERO CRD42017055549Catherine Staton and co-workers report on evidence about interventions against harmful alcohol use in low- and middle-income countries. 相似文献
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108.
Potent and selective activity of a new carbocyclic nucleoside analog (carbovir: NSC 614846) against human immunodeficiency virus in vitro 总被引:8,自引:0,他引:8
R Vince M Hua J Brownell S Daluge F C Lee W M Shannon G C Lavelle J Qualls O S Weislow R Kiser 《Biochemical and biophysical research communications》1988,156(2):1046-1053
Carbocyclic 2',3'-didehydro-2',3'-dideoxyguanosine (Carbovir: NSC 614846), a novel nucleoside analog, emerged as a potent and selective anti-HIV agent from a large screening program conducted by the National Cancer Institute and its contractors. Its hydrolytic stability and its ability to inhibit the infectivity and replication of HIV in T-cells at concentrations of approximately 200- to 400-fold below toxic concentrations make carbovir a top-priority candidate for development as a potential antiretroviral agent in the treatment of AIDS patients. 相似文献
109.
The isometric contractile response of the directly-stimulated rat diaphragm was studied before and following addition of the calcium channel blocker, nifedipine. Nifedipine (10 micrograms/ml and 30 micrograms/ml bath concentrations) significantly increased isometric force output during twitch and unfused tetanic stimulation. Force potentiation during unfused tetanic stimulation was equivalent during either high or low voltage stimulation. Nifedipine had no effect on the time to peak force, half relaxation time, or relaxation time during twitch stimulation; thus, both activation and relaxation rates were increased. The force potentiating actions of nifedipine persisted in a calcium-free bathing solution and were enhanced by d-tubocurarine. In contrast to the force enhancing effects found with twitch and unfused tetanic stimulation, nifedipine caused a small but significant reduction in isometric force during maximal fused tetanic stimulation. It is concluded that the force potentiating effects of nifedipine on rat diaphragm are not due to fiber recruitment, enhancement of neuromuscular excitation, or altered inward trans-sarcolemmal calcium flux, but may result from a direct effect of the drug on the rate of activation of the contractile apparatus. 相似文献
110.
Jillian A. Bristol Joshua Brand Makoto Ohashi Mark R. Eichelberg Alejandro Casco Scott E. Nelson Mitchell Hayes James C. Romero-Masters Dana C. Baiu Jenny E. Gumperz Eric C. Johannsen Huy Q. Dinh Shannon C. Kenney 《PLoS pathogens》2022,18(4)
Humans are infected with two types of EBV (Type 1 (T1) and Type 2 (T2)) that differ substantially in their EBNA2 and EBNA 3A/B/C latency proteins and have different phenotypes in B cells. T1 EBV transforms B cells more efficiently than T2 EBV in vitro, and T2 EBV-infected B cells are more lytic. We previously showed that both increased NFATc1/c2 activity, and an NFAT-binding motif within the BZLF1 immediate-early promoter variant (Zp-V3) contained in all T2 strains, contribute to lytic infection in T2 EBV-infected B cells. Here we compare cellular and viral gene expression in early-passage lymphoblastoid cell lines (LCLs) infected with either T1 or T2 EBV strains. Using bulk RNA-seq, we show that T2 LCLs are readily distinguishable from T1 LCLs, with approximately 600 differentially expressed cellular genes. Gene Set Enrichment Analysis (GSEA) suggests that T2 LCLs have increased B-cell receptor (BCR) signaling, NFAT activation, and enhanced expression of epithelial-mesenchymal-transition-associated genes. T2 LCLs also have decreased RNA and protein expression of a cellular gene required for survival of T1 LCLs, IRF4. In addition to its essential role in plasma cell differentiation, IRF4 decreases BCR signaling. Knock-down of IRF4 in a T1 LCL (infected with the Zp-V3-containing Akata strain) induced lytic reactivation whereas over-expression of IRF4 in Burkitt lymphoma cells inhibited both NFATc1 and NFATc2 expression and lytic EBV reactivation. Single-cell RNA-seq confirmed that T2 LCLs have many more lytic cells compared to T1 LCLs and showed that lytically infected cells have both increased NFATc1, and decreased IRF4, compared to latently infected cells. These studies reveal numerous differences in cellular gene expression in B cells infected with T1 versus T2 EBV and suggest that decreased IRF4 contributes to both the latent and lytic phenotypes in cells with T2 EBV. 相似文献