Cellugyrin (synaptogyrin-2) dependent pathways are used by bacterial cytolethal distending toxin and SARS-CoV-2 virus to gain cell entry.

Aggregatibacter actinomycetemcomitans cytolethal distending toxin (Cdt) is capable of intoxicating lymphocytes macrophages, mast cells and epithelial cells. Following Cdt binding to cholesterol, in the region of membrane lipid rafts, the CdtB and CdtC subunits are internalized and traffic to intracellular compartments. These events are dependent upon, cellugyrin, a critical component of synaptic like microvesicles (SLMVCg+). Target cells, such as Jurkat cells, rendered unable to express cellugyrin are resistant to Cdt-induced toxicity. Similar to Cdt, SARS-CoV-2 entry into host cells is initiated by binding to cell surface receptors, ACE-2, also associated with cholesterol-rich lipid rafts; this association leads to fusion and/or endocytosis of viral and host cell membranes and intracellular trafficking. The similarity in internalization pathways for both Cdt and SARS-CoV-2 led us to consider the possibility that cellugyrin was a critical component in both processes. Cellugyrin deficient Calu-3 cells (Calu-3Cg-) were prepared using Lentiviral particles containing shRNA; these cells were resistant to infection by VSV/SARS-CoV-2-spike pseudotype virus and partially resistant to VSV/VSV-G pseudotype virus. Synthetic peptides representing various regions of the cellugyrin protein were prepared and assessed for their ability to bind to Cdt subunits using surface plasmon resonance. Cdt was capable of binding to a region designated the middle outer loop (MOL) which corresponds to a region extending into the cytoplasmic surface of the SLMVCg+. SARS-CoV-2 spike proteins were assessed for their ability to bind to cellugyrin peptides; SARS-CoV-2 full length spike protein preferentially binds to a region within the SLMVCg+ lumen, designated intraluminal loop 1A. SARS-CoV-2-spike protein domain S1, which contains the receptor binding domains, binds to cellugyrin N-terminus which extends out from the cytoplasmic surface of SLMV. Binding specificity was further analyzed using cellugyrin scrambled peptide mutants. We propose that SLMVCg+ represent a component of a common pathway that facilitates pathogen and/or pathogen-derived toxins to gain host cell entry.

Predicting the Climate Impact of Healthcare Facilities Using Gradient Boosting Machines.

Health care accounts for 9-10% of greenhouse gas (GHG) emissions in the United States. Strategies for monitoring these emissions at the hospital level are needed to decarbonize the sector. However, data collection to estimate emissions is challenging, especially for smaller hospitals. We explored the potential of gradient boosting machines (GBM) to impute missing data on resource consumption in the 2020 survey of a consortium of 283 hospitals participating in Practice Greenhealth. GBM imputed missing values for selected variables in order to predict electricity use and beef consumption (R2=0.82) and anesthetic gas desflurane use (R2=0.51), using administrative data readily available for most hospitals. After imputing missing consumption data, estimated GHG emissions associated with these three examples totaled over 3 million metric tons of CO2 equivalent emissions (MTCO2e). Specifically, electricity consumption had the largest total carbon footprint (2.4 MTCO2e), followed by beef (0.6 million MTCO2e) and desflurane consumption (0.03 million MTCO2e) across the 283 hospitals. The approach should be applicable to other sources of hospital GHGs in order to estimate total emissions of individual hospitals and to refine survey questions to help develop better intervention strategies.

Virtual Reality for the Management of Pain and Anxiety for IR Procedures: A Prospective, Randomized, Pilot Study on Digital Sedation.

PURPOSE: To assess the analgesic and anxiolytic effects of virtual reality (VR) augmentation in patients undergoing peripherally inserted central catheter (PICC) placement or fine-needle aspiration thyroid biopsy. MATERIALS AND METHODS: This is a prospective, single-center randomized controlled trial with 107 patients enrolled. Patients were randomly assigned to receive standard of care (SOC) or SOC+VR during PICC or thyroid biopsy procedures. Pain and anxiety were individually measured using the visual analog scale (VAS) before and after the procedure. Vital signs including heart rate and systolic and diastolic blood pressure were recorded. One-way analysis of variance test and Games-Howell post hoc analysis were used to assess effect size and statistical significance between SOC and SOC+VR measures. RESULTS: The PICC cohort consisted of 59 patients (33 in SOC+VR and 26 in SOC), with a median age of 53.1 years (interquartile range [IQR], 38.3-62.7 years). The thyroid biopsy cohort consisted of 48 patients (26 in SOC+VR and 22 in SOC), with a median age of 60.1 years (IQR, 49.0-67.2 years). One-way analysis of individuals undergoing thyroid biopsies with adjunctive VR revealed an effect size of -1.74 points (SE ± 0.71; P = .018) on VAS pain scale when compared with SOC. Analysis of individuals undergoing PICC placements revealed an effect size of -1.60 points (SE ± 0.81; P = .053) on VAS anxiety when compared with SOC. CONCLUSIONS: VR as a nonpharmacologic adjunct reduced some procedure-related pain and anxiety without increasing the procedural duration.

Rapid and accurate detection of herpes simplex virus type 2 using a low-cost electrochemical biosensor.

Herpes simplex virus type 2 (HSV-2) infection, which is almost exclusively sexually transmitted, causes genital herpes. Although this lifelong and incurable infection is extremely widespread, currently there is no readily available diagnostic device that accurately detects HSV-2 antigens to a satisfactory degree. Here, we report an ultrasensitive electrochemical device that detects HSV-2 antigens within 9 min and costs just $1 (USD) to manufacture. The electrochemical biosensor is biofunctionalized with the human cellular receptor nectin-1 and detects the glycoprotein gD2, which is present within the HSV-2 viral envelope. The performance of the device is tested in a guinea pig model that mimics human biofluids, yielding 88.9% sensitivity, 100.0% specificity, and 95.0% accuracy under these conditions, with a limit of detection of 0.019 fg mL-1 for gD2 protein and 0.057 PFU mL-1 for titered viral samples. Importantly, no cross-reactions with other viruses were detected, indicating the adequate robustness and selectivity of the sensor. Our low-cost technology could facilitate more frequent testing for HSV-2.