Renin-angiotensin-system blockers and IgG antibodies in end-stage renal disease hemodialysis-receiving patients diagnosed with COVID-19 infection

OBJECTIVES

To evaluate the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections among patients receiving in-center hemodialysis (ICHD), the relationship between the IgG antibody levels against the virus and SARS-CoV-2-associated symptoms, hemodialysis adequacy, and the antihypertensives used in order to control blood pressure.

METHODS

A prospective observational study was carried out at a tertiary care center, King Fahad Kidney Center, Riyadh, Kingdom of Saudi Arabia, between November 2020 and January 2021. A total of 214 ICHD patients with end-stage renal disease (ESRD) were included, and the levels of their anti-SARS-CoV-2 IgG antibodies were assessed after obtaining their informed consent.

RESULTS

Our tests indicated that 15% of the patients in the study's population had detectable SARS-CoV-2 IgG antibodies, with more than half of them (53%) being asymptomatic. We also found that ESRD patients on angiotensin converting enzyme inhibitors or angiotensin receptor blockers (ACEIs/ARBs) had higher levels of SARS-CoV-2 IgG antibodies than patients not receiving this group of medications.

CONCLUSION

More studies are required to assess whether patients with a SARS-CoV-2 infection that do not have an indication for being prescribed ACEIs/ARBs would benefit from receiving these medications.

Transmission studies and the composition of prokaryotic communities associated with healthy and diseased Aplysina cauliformis sponges suggest that Aplysina Red Band Syndrome is a prokaryotic polymicrobial disease

Aplysina cauliformis, the Caribbean purple rope sponge, is commonly affected by Aplysina Red Band Syndrome. This transmissible disease manifests as circular lesions with red margins and results in bare spongin fibers. Leptolyngbya spp. appear to be responsible for the characteristic red coloration but transmission studies with a sponge-derived isolate failed to establish disease, leaving the etiology of ARBS unknown. To investigate the cause of ARBS, contact transmission experiments were performed between healthy and diseased sponges separated by filters with varying pore sizes. Transmission occurred when sponges were separated by filters with pore sizes ≥2.5 μm, suggesting a prokaryotic pathogen(s) but not completely eliminating eukaryotic pathogen(s). Using 16S rRNA gene sequencing methods, thirty-eight prokaryotic taxa were significantly enriched in diseased sponges, including Leptolyngbya, whereas seven taxa were only found in some, but not all, of the ARBS-affected sponges. These results do not implicate a single taxon, but rather a suite of taxa that changed in relative abundance with disease, suggesting a polymicrobial etiology as well as dysbiosis. As a better understanding of dysbiosis is gained, changes in the composition of associated prokaryotic communities may have increasing importance for evaluating and maintaining the health of individuals and imperiled coral reef ecosystems.

fMRI investigation of response inhibition, emotion, impulsivity, and clinical high-risk behavior in adolescents

High-risk behavior in adolescents is associated with injury, mental health problems, and poor outcomes in later life. Improved understanding of the neurobiology of high-risk behavior and impulsivity shows promise for informing clinical treatment and prevention as well as policy to better address high-risk behavior. We recruited 21 adolescents (age 14–17) with a wide range of high-risk behavior tendencies, including medically high-risk participants recruited from psychiatric clinics. Risk tendencies were assessed using the Adolescent Risk Behavior Screen (ARBS). ARBS risk scores correlated highly (0.78) with impulsivity scores from the Barratt Impulsivity scale (BIS). Participants underwent 4.7 Tesla functional magnetic resonance imaging (fMRI) while performing an emotional Go/NoGo task. This task presented an aversive or neutral distractor image simultaneously with each Go or NoGo stimulus. Risk behavior and impulsivity tendencies exhibited similar but not identical associations with fMRI activation patterns in prefrontal brain regions. We interpret these results as reflecting differences in response inhibition, emotional stimulus processing, and emotion regulation in relation to participant risk behavior tendencies and impulsivity levels. The results are consistent with high impulsivity playing an important role in determining high risk tendencies in this sample containing clinically high-risk adolescents.