Transmission of viruses via our microbiomes.

BackgroundBacteria inhabiting the human body have important roles in a number of physiological processes and are known to be shared amongst genetically-related individuals. Far less is known about viruses inhabiting the human body, but their ecology suggests they may be shared between close contacts.ResultsHere, we report the ecology of viruses in the guts and mouths of a cohort and demonstrate that substantial numbers of gut and oral viruses were shared amongst genetically unrelated, cohabitating individuals. Most of these viruses were bacteriophages, and each individual had distinct oral and gut viral ecology from their housemates despite the fact that some of their bacteriophages were shared. The distribution of bacteriophages over time within households indicated that they were frequently transmitted between the microbiomes of household contacts.ConclusionsBecause bacteriophages may shape human oral and gut bacterial ecology, their transmission to household contacts suggests they could have substantial roles in shaping the microbiota within a household

Microbial diversity in individuals and their household contacts following typical antibiotic courses.

BackgroundAntibiotics are a mainstay of treatment for bacterial infections worldwide, yet the effects of typical antibiotic prescriptions on human indigenous microbiota have not been thoroughly evaluated. We examined the effects of the two most commonly prescribed antibiotics (amoxicillin and azithromycin) in the USA to discern whether short-term antibiotic courses may have prolonged effects on human microbiota.ResultsWe sampled the feces, saliva, and skin specimens from a cohort of unrelated, cohabitating individuals over 6 months. An individual in each household was given an antibiotic, and the other a placebo to discern antibiotic impacts on microbiota, as well as determine whether antibiotic use might reshape the microbiota of each household. We observed household-specific patterns of microbiota on each body surface, which persevered despite antibiotic perturbations. While the gut microbiota within an individual became more dissimilar over time, there was no evidence that the use of antibiotics accelerated this process when compared to household members. There was a significant change in microbiota diversity in the gut and mouth in response to antibiotics, but analogous patterns were not observed on the skin. Those who received 7 days of amoxicillin generally had greater reductions in diversity compared to those who received 3 days, in contrast to those who received azithromycin.ConclusionsAs few as 3 days of treatment with the most commonly prescribed antibiotics can result in sustained reductions in microbiota diversity, which could have implications for the maintenance of human health and resilience to disease

Genetic liability to rheumatoid arthritis on autism and autistic traits:polygenic risk score and mendelian randomization analyses

Higher prevalence of autism in offspring born to mothers with rheumatoid arthritis has been reported in observational studies. We investigated (a) the associations between maternal and offspring’s own genetic liability for rheumatoid arthritis and autism-related outcomes in the offspring using polygenic risk scores (PRS) and (b) whether the effects were causal using Mendelian randomization (MR). Using the latest genome-wide association (GWAS) summary data on rheumatoid arthritis and individual-level data from the Avon Longitudinal Study of Parents and Children, United Kingdom, we constructed PRSs for maternal and offspring genetic liability for rheumatoid arthritis (single-nucleotide polymorphism [SNP] p-value threshold 0.05). We investigated associations with autism, and autistic traits: social and communication difficulties, coherence, repetitive behaviours and sociability. We used modified Poisson regression with robust standard errors. In two-sample MR analyses, we used 40 genome-wide significant SNPs for rheumatoid arthritis and investigated the causal effects on risk for autism, in 18,381 cases and 27,969 controls of the Psychiatric Genetics Consortium and iPSYCH. Sample size ranged from 4992 to 7849 in PRS analyses. We found little evidence of associations between rheumatoid arthritis PRSs and autism-related phenotypes in the offspring (maternal PRS on autism: RR 0.89, 95%CI 0.73–1.07, p = 0.21; offspring’s own PRS on autism: RR 1.11, 95%CI 0.88–1.39, p = 0.39). MR results provided little evidence for a causal effect (IVW OR 1.01, 95%CI 0.98–1.04, p = 0.56). There was little evidence for associations between genetic liability for rheumatoid arthritis on autism-related outcomes in offspring. Lifetime risk for rheumatoid arthritis has no causal effects on autism

Chromium Tolerant Microbial Communities from the Chesapeake Bay Watershed

Chromium tolerant bacteria were enumerated from portions of the Chesapeake Bay watershed and examined for their potential to reduce Cr(VI). Water and sediment samples were collected from various locations in Baltimore Harbor and Bear Creek, as well as Sandy Point State Park in Maryland and the Anacostia River in Washington, DC. Samples were spread onto agar plates with CrO42- (5 ppm) as the sole terminal electron acceptor. Plates were incubated anaerobically and colony forming units (CFU) enumerated. CFU arising on minimal-CrO42- medium ranged from 103-104 mL-1 or g-1 and community estimates from sites in proximity to Baltimore City were approximately 6-30X higher than distal sites. Bacterial identification by BIOLOG™ or 16S rRNA sequencing indicated the presence of bacteria of the genera Klebsiella, Pseudomonas, Burkholderia, Kluyvera and others. Typical Cr(VI) reduction rates by these isolates were significantly lower than Shewanella oneidensis, a known metal-reducing bacterium. Results suggested that microbial communities in the Chesapeake Bay watershed, particularly in Baltimore Harbor and Bear Creek, had a high tolerance for Cr(VI) and/or could grow slowly with Cr(VI) as a terminal electron acceptor. However, the isolates did not rapidly degrade Cr(VI) in the laboratory

Dynamic Interchanging Native States of Lymphotactin Examined by SNAPP-MS

The human chemokine lymphotactin (Ltn) is a remarkable protein that interconverts between two unrelated native state structures in the condensed phase. It is possible to shift the equilibrium toward either conformation with selected sequence substitutions. Previous results have shown that a disulfide-stabilized variant preferentially adopts the canonical chemokine fold (Ltn10), while a single amino acid change (W55D) favors the novel Ltn40 dimeric structure. Selective noncovalent adduct protein probing (SNAPP) is a recently developed method for examining solution phase protein structure. Herein, it is demonstrated that SNAPP can easily recognize and distinguish between the Ltn10 and Ltn40 states of lymphotactin in aqueous solution. The effects of organic denaturants, acid, and disulfide bond reduction and blocking were also examined using SNAPP for the CC3, W55D, and wild type proteins. Only disulfide reduction was shown to significantly perturb the protein, and resulted in considerably decreased adduct formation consistent with loss of tertiary/secondary structure. Cold denaturation experiments demonstrated that wild-type Ltn is the most temperature sensitive of the three proteins. Examination of the higher charge states in all experiments, which are presumed to represent transition state structures between Ltn-10 and Ltn-40, reveals increased 18C6 attachment relative to the more folded structures. This observation is consistent with increased competitive intramolecular hydrogen bonding, which may guide the transition. Experiments examining the gas phase structures revealed that all three proteins can be structurally distinguished in the gas phase. In addition, the gas phase experiments enabled identification of preferred adduct binding sites

VLBI observations of weak sources using fast frequency switching

We have developed a new phase referencing technique for high frequency VLBI observations. In conventional phase referencing, one interleaves short scans on a nearby phase calibrator between the target source observations. In fast frequency switching described here, one observes the target source continuously while switching rapidly between the target frequency and a lower reference frequency. We demonstrate that the technique allows phase calibration almost reaching the thermal noise limit and present the first detection of the AGN in the FR I radio galaxy NGC 4261 at 86 GHz. Although point-like, this is the weakest source ever detected with VLBI at this frequency.Comment: Accepted by A&A, 14 pages, 12 figures, needs aa.cls, aas_macros.sty and amsmath.sty, replaced due reformattin

Satisfaction with teledermatology in an underserved urban shelter setting

Problem Statement: People experiencing homelessness (PEH) face disproportionate access to dermatologic care. Teledermatology is a platform that may improve access to medical care in underserved communities. The literature is lacking on this topic. Project Aim: The purpose of this quality improvement initiative is to evaluate patient and provider satisfaction with teledermatology in an urban shelter setting. Satisfaction surveys will be distributed over one year to provide measurable data that are determinate (designed to highlight multiple satisfaction metrics, numerically), concise (designed with functionality and efficiency in mind) and relevant (validated across multiple studies).https://jdc.jefferson.edu/medposters/1021/thumbnail.jp

Evolution of the Halpha luminosity function

The Smithsonian Hectospec Lensing Survey (SHELS) is a window on the star formation history over the last 4 Gyr. SHELS is a spectroscopically complete survey for Rtot < 20.3 over 4 square degrees. We use the 10k spectra to select a sample of pure star forming galaxies based on their Halpha emission line. We use the spectroscopy to determine extinction corrections for individual galaxies and to remove active galaxies in order to reduce systematic uncertainties. We use the large volume of SHELS with the depth of a narrowband survey for Halpha galaxies at z ~ 0.24 to make a combined determination of the Halpha luminosity function at z ~ 0.24. The large area covered by SHELS yields a survey volume big enough to determine the bright end of the Halpha luminosity function from redshift 0.100 to 0.377 for an assumed fixed faint-end slope alpha = -1.20. The bright end evolves: the characteristic luminosity L* increases by 0.84 dex over this redshift range. Similarly, the star formation density increases by 0.11 dex. The fraction of galaxies with a close neighbor increases by a factor of 2-5 for L(Halpha) >~ L* in each of the redshift bins. We conclude that triggered star formation is an important influence for star forming galaxies with Halpha emission.Comment: 26 pages, 23 figures, submitted to ApJ; version with high resolution figures available at http://www.cfa.harvard.edu/~ewestra/publications

Association Between Handover of Anesthesiology Care and 1-Year Mortality Among Adults Undergoing Cardiac Surgery

Importance Handovers of anesthesia care from one anesthesiologist to another is an important intraoperative event. Despite its association with adverse events after noncardiac surgery, its impact in the context of cardiac surgery remains unclear. Objective To compare the outcomes of patients who were exposed to anesthesia handover vs those who were unexposed to anesthesia handover during cardiac surgery. Design, Setting, and Participants This retrospective cohort study in Ontario, Canada, included Ontario residents who were 18 years or older and had undergone coronary artery bypass grafting or aortic, mitral, tricuspid valve, or thoracic aorta surgical procedures between 2008 and 2019. Exclusion criteria were non-Ontario residency status and other concomitant procedures. Statistical analysis was conducted from April 2021 to June 2021, and data collection occurred between November 2020 to January 2021. Exposures Complete handover of anesthesia care, where the case is completed by the replacement anesthesiologist. Main Outcomes and Measures The coprimary outcomes were mortality within 30 days and 1 year after surgery. Secondary outcomes were patient-defined adverse cardiac and noncardiac events (PACE), intensive care unit (ICU), and hospital lengths of stay (LOS). Inverse probability of treatment weighting based on the propensity score was used to estimate adjusted effect measures. Mortality was assessed using a Cox proportional hazard model, PACE using a cause-specific hazard model with death as a competing risk, and LOS using Poisson regression. Results Of the 102 156 patients in the cohort, 25 207 (24.7%) were women; the mean (SD) age was 66.4 (10.8) years; and 72 843 of surgical procedures (71.3%) were performed in teaching hospitals. Handover occurred in 1926 patients (1.9%) and was associated with higher risks of 30-day mortality (hazard ratio [HR], 1.89; 95% CI, 1.41-2.54) and 1-year mortality (HR, 1.66; 95% CI, 1.31-2.12), as well as longer ICU (risk ratio [RR], 1.43; 95% CI, 1.22-1.68) and hospital (RR, 1.17; 95% CI, 1.06-1.28) LOS. There was no statistically significant association between handover and PACE (30 days: HR 1.09; 95% CI, 0.79-1.49; 1 year: HR 0.89; 95% CI, 0.70-1.13). Conclusions and Relevance Handover of anesthesia care during cardiac surgical procedures was associated with higher 30-day and 1-year mortality rates and increased health care resource use. Further research is needed to evaluate and systematically improve the handover process qualitatively