Diffuse flow environments within basalt- and sediment-based hydrothermal vent ecosystems harbor specialized microbial communities

Hydrothermal vents differ both in surface input and subsurface geochemistry. The effects of these differences on their microbial communities are not clear. Here, we investigated both alpha and beta diversity of diffuse flow-associated microbial communities emanating from vents at a basalt-based hydrothermal system along the East Pacific Rise (EPR) and a sediment-based hydrothermal system, Guaymas Basin. Both Bacteria and Archaea were targeted using high throughput 16S rRNA gene pyrosequencing analyses. A unique aspect of this study was the use of a universal set of 16S rRNA gene primers to characterize total and diffuse flow-specific microbial communities from varied deep-sea hydrothermal environments. Both surrounding seawater and diffuse flow water samples contained large numbers of Marine Group I (MGI) Thaumarchaea and Gammaproteobacteria taxa previously observed in deep-sea systems. However, these taxa were geographically distinct and segregated according to type of spreading center. Diffuse flow microbial community profiles were highly differentiated. In particular, EPR dominant diffuse flow taxa were most closely associated with chemolithoautotrophs, and off axis water was dominated by heterotrophic-related taxa, whereas the opposite was true for Guaymas Basin. The diversity and richness of diffuse flow-specific microbial communities were strongly correlated to the relative abundance of Epsilonproteobacteria, proximity to macrofauna, and hydrothermal system type. Archaeal diversity was higher than or equivalent to bacterial diversity in about one third of the samples. Most diffuse flow-specific communities were dominated by OTUs associated with Epsilonproteobacteria, but many of the Guaymas Basin diffuse flow samples were dominated by either OTUs within the Planctomycetes or hyperthermophilic Archaea. This study emphasizes the unique microbial communities associated with geochemically and geographically distinct hydrothermal diffuse flow environments

Antibody-Based Ticagrelor Reversal Agent in Healthy Volunteers.

BACKGROUND: Ticagrelor is an oral P2Y12 inhibitor that is used with aspirin to reduce the risk of ischemic events among patients with acute coronary syndromes or previous myocardial infarction. Spontaneous major bleeding and bleeding associated with urgent invasive procedures are concerns with ticagrelor, as with other antiplatelet drugs. The antiplatelet effects of ticagrelor cannot be reversed with platelet transfusion. A rapid-acting reversal agent would be useful. METHODS: In this randomized, double-blind, placebo-controlled, phase 1 trial, we evaluated intravenous PB2452, a monoclonal antibody fragment that binds ticagrelor with high affinity, as a ticagrelor reversal agent. We assessed platelet function in healthy volunteers before and after 48 hours of ticagrelor pretreatment and again after the administration of PB2452 or placebo. Platelet function was assessed with the use of light transmission aggregometry, a point-of-care P2Y12 platelet-reactivity test, and a vasodilator-stimulated phosphoprotein assay. RESULTS: Of the 64 volunteers who underwent randomization, 48 were assigned to receive PB2452 and 16 to receive placebo. After 48 hours of ticagrelor pretreatment, platelet aggregation was suppressed by approximately 80%. PB2452 administered as an initial intravenous bolus followed by a prolonged infusion (8, 12, or 16 hours) was associated with a significantly greater increase in platelet function than placebo, as measured by multiple assays. Ticagrelor reversal occurred within 5 minutes after the initiation of PB2452 and was sustained for more than 20 hours (P\u3c0.001 after Bonferroni adjustment across all time points for all assays). There was no evidence of a rebound in platelet activity after drug cessation. Adverse events related to the trial drug were limited mainly to issues involving the infusion site. CONCLUSIONS: In healthy volunteers, the administration of PB2452, a specific reversal agent for ticagrelor, provided immediate and sustained reversal of the antiplatelet effects of ticagrelor, as measured by multiple assays. (Funded by PhaseBio Pharmaceuticals; ClinicalTrials.gov number, NCT03492385.)

Is There a Relationship Between the Concentration of Same-Sex Couples and Tobacco Retailer Density?

Tobacco use is markedly higher among lesbian, gay, and bisexual populations than heterosexuals. Higher density of tobacco retailers is found in neighborhoods with lower income and more racial/ethnic minorities. Same-sex couples tend to live in similar neighborhoods, but the association of this demographic with tobacco retailer density has not been examined

Monitoring of gene knockouts: genome-wide profiling of conditionally essential genes

Monitoring of gene knockouts is a new microarray-based genetic technique used for genome-wide identification of conditionally essential genes in bacteri

Patient and provider‐level barriers to hepatitis C screening and linkage to care: A mixed‐methods evaluation

Achieving practice change can be challenging when guidelines shift from a selective risk‐based strategy to a broader population health strategy, as occurred for hepatitis C (HCV) screening (2012‐2013). We aimed to evaluate patient and provider barriers that contributed to suboptimal HCV screening and linkage‐to‐care rates after implementation of an intervention to improve HCV screening and linkage‐to‐care processes in a large, public integrated healthcare system following the guidelines change. As part of a mixed‐methods study, we collected data through patient surveys (n = 159), focus groups (n = 9) and structured observation of providers and staff (n = 9). We used these findings to then inform domains for the second phase, which consisted of semi‐structured interviews with patients across the screening‐treatment continuum (n = 24) and providers and staff at primary care and hepatology clinics (n = 21). We transcribed and thematically analysed interviews using an integrated inductive and deductive framework. We identified lack of clarity about treatment cost, treatment complications and likelihood of cure as ongoing patient‐level barriers to screening and linkage to care. Provider‐level barriers included scepticism about establishing HCV screening as a quality metric given competing clinical priorities, particularly for patients with multiple comorbidities. However, most felt positively about adding HCV as a quality metric to enhance HCV screening and linkage to care. Provider engagement yielded suggestions for process improvements that resulted in increased stakeholder buy‐in and real‐time enhancements to the HCV screening process intervention. Systematic data collection at baseline and during practice change implementation may facilitate adoption and adaptation to improve HCV screening guideline implementation. Findings identified several key opportunities and lessons to enhance the impact of practice change interventions to improve HCV screening and treatment delivery.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155892/1/jvh13278.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155892/2/jvh13278_am.pd