Abundance and community composition of invasive Intertidal Watersipora on the San Francisco Bay Area Outer Coast

Invasive species can lead to serious ecological changes. The San Francisco Bay area is one of the most invaded areas in the world due to the commercial shipping industry and recreational water vessels. While the intertidal is not widely invaded, the harbors and docks are. One exception to this is the invasive, colonial filter-feeding bryozoan Watersipora, which has been found at various rocky outer coast sites. Further investigation into how the sites are invaded by this organism and their impact on native species must be carried out. In this project, at four intertidal sites around the SF Bay outflow, we compared Watersipora abundance at two tidal heights and assessed interactions with organisms. Using two parallel transects, separated by approximately 8 meters, we documented size and growth form of all colonies located one meter to each side of the transect. To assess community interactions, we centered a 15x15 centimeter quadrat over every other colony and photographed it. Using the photographs, organisms within each quadrat were quantified and interactions between Watersipora and organisms were assessed. At all sites, Watersipora abundance was higher in the lower intertidal than the shoreward transect. Comparing the four sites, the two sites more distant from the outflow had more total counts of colonies, in comparison to the two bay proximal sites. This may suggest that the bay outflow isn’t the source of Watersipora spread along the coast, even though it is abundant inside the Bay itself. Investigating community composition around Watersipora colonies showed most interactions with coralline algae, sponges, polychaete tubes, and anemones. Specifically, it was observed overgrowing Phragmatopoma californica tubes, and both overgrowing and being overgrown by sponges. Looking forward, investigation into how Watersipora impacts species in the same ecological niche will be critical to understanding how this invasive organism is impacting the rocky intertidal community

Impact of early-stage HIV transmission on treatment as prevention

Timely HIV treatment improves health (1) and reduces transmission (2). These individual- level benefits of HIV treatment for both clinical and preventive purposes are well established, but several questions remain about the population-level impact of HIV treatment as prevention (3). In PNAS, Eaton and Hallett (4) use a mathematical model to address one such question: Does the proportion of transmission during early HIV infection affect the impact of HIV treatment on HIV incidence

Recent key advances in human immunodeficiency virus medicine and implications for China

In this article we summarize several recent major developments in human immunodeficiency virus treatment, prevention, outcome, and social policy change. Updated international guidelines endorse more aggressive treatment strategies and safer antiretroviral drugs. New antiretroviral options are being tested. Important lessons were learned in the areas of human immunodeficiency virus vaccines and microbicide gels from clinical studies, and additional trials in prevention, especially pre-exposure prophylaxis, are nearing completion. Insight into the role of the virus in the pathogenesis of diseases traditionally thought to be unrelated to acquired immunodeficiency syndrome has become a driving force for earlier and universal therapy. Lastly, we review important achievements of and future challenges facing China as she steps into her eighth year of the National Free Antiretroviral Treatment Program

Treatment to Prevent Transmission of HIV‐1

Antiretroviral agents (ART) have the potential to prevent HIV transmission by reducing the concentration of HIV in blood and genital secretions. Indeed, mathematical models with favorable assumptions suggest the potential of ART to stop the spread of HIV. Empirical results from ecological and population based studies, and several short term observational studies involving HIV discordant heterosexual couples suggest that ART reduces HIV transmission. A multinational randomized controlled trial (NIH NPTN052) also examining the reliability and durability of ART as prevention in HIV discordant couples is underway. The latter and other studies also consider sexual risk taking behavior, and transmission of HIV resistant variants when ART is used as prevention. Early HIV detection and treatment (“test and treat”) are being considered as an important prevention strategy. In this article, we review the data supporting the use of ART to prevent HIV transmission, and critically examine the public health implications of this strategy

Rebound of COVID-19 With Nirmatrelvir-Ritonavir Antiviral Therapy

In their article, Edelstein and colleagues provide the results of an observational study of virologic response in patients who received treatment with nirmatrelvir–ritonavir (N-R) versus those who received no COVID-19 therapy. The editorialists discuss the findings and emphasize the need for further consideration of the dosage, timing, and duration of treatment to inform optimal use of N-R

Chinaʼs syphilis epidemic: epidemiology, proximate determinants of spread, and control responses

China has experienced an increase in the incidence and prevalence of syphilis that is especially remarkable since this infection was virtually eradicated in the country 50 years ago. The purpose of this analysis is to provide an overview of recent literature on syphilis proximate determinants and potential public health responses

Effects of human serum on the growth and metabolism of Neisseria gonorrhoeae: an alternative view of serum.

Humans are the sole reservoir of Neisseria gonorrhoeae, an organism which undergoes a marked increase in metabolic rate after exposure to a low-molecular-weight, heat-stable component(s) of human serum. Further studies on the effect of serum on gonococcal metabolism were undertaken. Gonococcal broth (GCB) is commonly used for in vitro cultivation of gonococci. Gonococci suspended in GCB plus 10% serum exhibited oxygen consumption rates of 139% (P less than 0.01) and 456% (P less than 0.01) of those suspended in GCB or Hanks balanced salt solution, respectively. A twofold increase in growth rate also resulted from the addition of 10% serum to GCB. Gonococcal 14C-labeled adenine incorporation increased threefold with 10% serum supplementation of Hanks balanced salt solution. Dialysis of serum in 1,000-molecular-weight exclusion tubing removed the stimulatory factor(s). Neither correction of anion-cation concentrations altered by dialysis nor addition of substances of known importance to the metabolism of gonococci (i.e., lactate, pyruvate, cysteine, ATP, AMP, NADPH, amino acids, malate, and glutathione) to dialyzed serum reconstituted stimulatory capacity. The effect of serum on gonococcal glucose-catabolic pathways was measured by modified radiospirometry. An apparent threefold increase in Entner-Doudoroff and pentose phosphate pathway activities was induced by 10% serum, as was the increased shunting of glucose-derived glyceraldehyde-3-phosphate into these pathways. These metabolic changes did not allow specific identification of the serum stimulatory factor(s). Acetate, the major by-product of gonococcal glucose catabolism, inhibited gonococcal oxygen consumption as previously reported. A high-molecular-weight serum component, probably albumin, reversed acetate-mediated inhibition of gonococcal oxygen consumption, identifying a second mechanism by which serum increases gonococcal metabolism. These results suggest that supplementation of growth media with serum should be considered to provide N. gonorrhoeae with conditions more consistent with its normal environment

Outpatient Treatment of SARS-CoV-2 Infection to Prevent COVID-19 Progression

As of March 2021, COVID-19 has caused more than 123 million infections, and almost 3 million deaths worldwide. Dramatic advances have been made in vaccine development and non-pharmaceutical interventions to stop the spread of infection. But treatments to stop the progression of disease are limited. A wide variety of "repurposed" drugs explored for treatment of COVID-19 have had little or no benefit. More recently, intravenous monoclonal antibody (mAb) combinations have been authorized by the US FDA for emergency use (EUA) for outpatients with mild to moderate COVID-19 including some active against emerging SARS-COV-2 variants of concern (VOC). Easier to administer therapeutics including intramuscular and subcutaneous mAbs and oral antivirals are in clinical trials. Reliable, safe, effective COVID-19 treatment for early infection in the outpatient setting is of urgent and critical importance. Availability of such treatment should lead to reduced progression of COVID-19