Nanomolar concentrations of the photodynamic compound TLD-1433 effectively inactivate numerous human pathogenic viruses.

The anti-viral properties of a small (≈1 kDa), novel Ru(II) photo dynamic compound (PDC), referred to as TLD-1433 (Ruvidar™), are presented. TLD-1433 had previously been demonstrated to exert strong anti-bacterial and anti-cancer properties. We evaluated the capacity of TLD-1433 to inactivate several human pathogenic viruses. TLD-1433 that was not photo-activated was capable of effectively inactivating 50 % of influenza H1N1 virus (ID50) at a concentration of 117 nM. After photo-activation, the ID50 was reduced to <10 nM. The dose of photo-activated TLD-1433 needed to reduce H1N1 infectivity >99 % (ID99) was approximately 170 nM. Similarly, the ID99 of photo-activated TLD-1433 was determined to range from about 20 to 120 nM for other tested enveloped viruses; specifically, a human coronavirus, herpes simplex virus, the poxvirus Vaccinia virus, and Zika virus. TLD-1433 also inactivated two tested non-enveloped viruses; specifically, adenovirus type 5 and mammalian orthoreovirus, but at considerably higher concentrations. Analyses of TLD-1433-treated membranes suggested that lipid peroxidation was a major contributor to enveloped virus inactivation. TLD-1433-mediated virus inactivation was temperature-dependent, with approximately 10-fold more efficient virucidal activity when viruses were treated at 37 °C than when treated at room temperature (∼22 °C). The presence of fetal bovine serum and virus solution turbidity reduced TLD-1433-mediated virucidal efficiency. Immunoblots of TLD-1433-treated human coronavirus indicated the treated spike protein remained particle-associated.

The long weight: association between distressed communities index and long-term weight outcomes following bariatric surgery.

BACKGROUND: Socioeconomic status (SES) is multifactorial, and its effect on post-bariatric weight recurrence is unclear. Distressed Community Index (DCI) is a composite SES score measuring community economic well-being. This study aims to evaluate the effect of DCI on long-term post-bariatric weight outcomes. METHODS: Retrospective analysis of patients undergoing primary laparoscopic Roux-en-Y gastric bypass or sleeve gastrectomy between 2015 and 2020 was performed. All weights in the electronic medical record (EMR), including non-bariatric visits, were captured. Patients were stratified into low tier (LT) and high tier (HT) DCI groups. RESULTS: Of 583 patients, 431 (73.9%) were HT and 152 (26.1%) were LT. Average bariatric follow up was 1.78 ± 1.6 years and average postoperative weight in the EMR was 3.96 ± 2.26 years. Rates of bariatric follow up within the last year were similar (13.8% LT vs 16.2% HT, p = 0.47). LT had higher percent total body weight loss (%TWL; 26% LT vs 23% HT, p < 0.01) and percent excess weight loss (%EWL; 62% vs 57%, p = 0.04) at 1 year on univariate analysis. On multivariate linear regression adjusting for baseline characteristics and surgery type, there were no differences in %EWL between groups at 1 year (p = 0.22), ≥ 3 years (p = 0.53) or ≥ 5 years (p = 0.34) postop. While on univariate analysis LT only trended towards greater percentage of patients with > 15% increase from their 1-year weight (33.3% LT vs 21.0% HT, p = 0.06), on multivariate analysis this difference was significant (OR 2.0, LT 95%CI 1.41-2.84). There were no differences in the percentage of patients with > 15% decrease in %EWL from 1 to 3 + years postop between groups (OR 0.98, LT 95% CI 0.72-1.35). CONCLUSIONS: While low tier patients had similar weight loss at 1 year, they were twice as likely to have weight recurrence at ≥ 3 years. Further studies are needed to identify factors contributing to greater weight recurrence among this population.

Ubiquitin variants potently inhibit SARS-CoV-2 PLpro and viral replication via a novel site distal to the protease active site.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has made it clear that combating coronavirus outbreaks benefits from a combination of vaccines and therapeutics. A promising drug target common to all coronaviruses-including SARS-CoV, MERS-CoV, and SARS-CoV-2-is the papain-like protease (PLpro). PLpro cleaves part of the viral replicase polyproteins into non-structural protein subunits, which are essential to the viral replication cycle. Additionally, PLpro can cleave both ubiquitin and the ubiquitin-like protein ISG15 from host cell substrates as a mechanism to evade innate immune responses during infection. These roles make PLpro an attractive antiviral drug target. Here we demonstrate that ubiquitin variants (UbVs) can be selected from a phage-displayed library and used to specifically and potently block SARS-CoV-2 PLpro activity. A crystal structure of SARS-CoV-2 PLpro in complex with a representative UbV reveals a dimeric UbV bound to PLpro at a site distal to the catalytic site. Yet, the UbV inhibits the essential cleavage activities of the protease in vitro and in cells, and it reduces viral replication in cell culture by almost five orders of magnitude.

Frontrunners in the race to develop a SARS-CoV-2 vaccine.

Numerous studies continue to be published on the COVID-19 pandemic that is being caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Given the rapidly evolving global response to SARS-CoV-2, here we primarily review the leading COVID-19 vaccine strategies that are currently in Phase III clinical trials. Nonreplicating viral vector strategies, inactivated virus, recombinant protein subunit vaccines, and nucleic acid vaccine platforms are all being pursued in an effort to combat the infection. Preclinical and clinal trial results of these efforts are examined as well as the characteristics of each vaccine strategy from the humoral and cellular immune responses they stimulate, effects of any adjuvants used, and the potential risks associated with immunization such as antibody-dependent enhancement. A number of promising advancements have been made toward the development of multiple vaccine candidates. Preliminary data now emerging from phase III clinical trials show encouraging results for the protective efficacy and safety of at least 3 frontrunning candidates. There is hope that one or more will emerge as potent weapons to protect against SARS-CoV-2.