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Objectives: Rapid antigen testing (RAT) for coronavirus disease 2019 (COVID-19) has lower sensitivity but high accuracy during the early stage when compared to reverse transcription quantitative polymerase chain reaction (RT-qPCR). The aim of this study was to investigate the concordance between RAT and RT-qPCR results, and their prediction of disease transmission. Methods: This single-center retrospective observational study of inpatients with COVID-19 was conducted from March 6 to June 14, 2020. Nasopharyngeal swabs were used to perform RAT and RT-qPCR. The primary endpoint was concordance between RAT and RT-qPCR results. The secondary endpoints were the factors causing disagreement in the results and the estimated transmissibility in RT-qPCR-positive patients with mild symptoms. Results: Overall, 229 samples in viral transport medium (VTM) were obtained from 105 patients. The positive and negative concordance rates for VTM were 41% vs 99% (κ = 0.37) and 72% vs 100% (κ = 0.50) for samples collected on disease days 2–9. An increased body temperature (odds ratio 0.54) and absence of drugs with potential antiviral effect (odds ratio 0.48) yielded conflicting results. RAT was associated with the ability to end isolation (OR 0.11, 95% confidence interval 0.20–0.61). Conclusions: RAT and RT-qPCR results were highly consistent for samples collected at the appropriate time and could be useful for inferring the possibility of transmissibility.

Remdesivir is an antiviral drug that results in clinical improvement after five days of treatment and accelerates recovery by 31%. No studies have discussed the pharmacokinetic analysis of remdesivir in patients with severe COVID-19 requiring extracorporeal membrane oxygenation (ECMO). A 63-year-old American man who underwent mechanical ventilation and ECMO for severe COVID-19 was administered remdesivir for ten days. The loading dosage was 200 mg at 7 PM on day 12 and 100 mg daily at 0:00 PM from day 13–21, administered within 1 h. The pharmacokinetic analysis was performed. The serum creatinine concentration was within the normal range of 0.5–0.7 mg/dL during treatment. According to the pharmacokinetic analysis, the plasma concentrations of remdesivir and GS-441524 4 h after administration (C4) were 662 ng/mL and 58 ng/mL, respectively, and the concentrations 18 h after administration (C18) were 32 ng/mL and 44 ng/mL, respectively. Therefore, the half-life of remdesivir and GS-441524 was 3.2 and 35.1 h, respectively. Monitoring the plasma concentrations of remdesivir and GS-441524 in patients undergoing ECMO may be necessary.

Summary: Background: The coronavirus disease 2019 (COVID-19) continues to spread around the world. In addition to community-acquired infections, nosocomial infections are also a major social concern. The likelihood of environmental contamination and transmission of the virus based on disease severity is unknown. Methods: We collected nasopharyngeal, environmental and air samples from patients with COVID-19 admitted to the National Centre for Global Health and Medicine between January 29th and February 29th, 2020. The patients were classified by severity of disease. The collected samples were tested using severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) real-time reverse transcription polymerase chain reaction (real-time RT-PCR). Results: SARS-CoV-2 was not detected in a subset of 11 air samples. Of the 141 environmental samples collected from three patient bays and two single rooms, four samples tested positive for SARS-CoV-2 by real-time RT-PCR. Detections were made on the surface of a stethoscope used in the care of a patient with severe disease, on the intubation tube of a patient classified as critical (and on ventilator management), and on the surface of a gown worn by the nurse providing care. Conclusions: Regardless of the patients' disease severity, SARS-CoV-2 was detected on very few environmental surfaces. However, detection of SARS-CoV-2 on stethoscopes used in the care of multiple patients and on the surface of gowns worn by clinical staff indicates that medical devices may be linked to the spread of infection.

Summary: Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has spready globally. This report describes the person-to-person transmission of the virus in a hospital setting. Presentation of case: A 63-year-old man with pneumonia and a 70-year-old man without symptoms were admitted to a tertiary hospital with SARS-CoV-2 infection. Both men were accompanied by their wives, who stayed with their husbands during their hospitalisation. The wives of Patient 1 and Patient 2 tested positive and negative for SARS-CoV-2, respectively. Of the environmental samples tested, 1/21 and 0/25 from the rooms of Patient 1 and Patient 2, respectively, tested positive for SARS-CoV-2. Patient 1’s wife appeared to have acquired infection during her husband’s hospitalisation. Discussion: The study had several limitations, including methodology inconsistencies. Additionally, a viral culture was not performed to demonstrate the viability of the virus identified in the environmental sample. Finally, the wife of Patient 1 stayed on the Diamond Princess cruise ship for 4 days before being transferred to the hospital and may have been infected on the ship and not while in the hospital. Conclusion: Our study suggests that airborne transmission of SARS-CoV-2 may be limited. However, owing to the abovementioned limitations, the results should be interpreted with caution.

Japanese pigs are farmed by giving them cereal crop feed, consequently, the Japanese pig industry increases indirect impact on the environment. Contrastingly, French pigs are farmed by feeding them an appropriate quantity of low-protein feed to decrease environmental impact of feed cereal cultivation. The proposed study aims to assess the carbon and water footprints of conventional and low-protein pig feeds in the French model and extends these findings to Japan. When essential amino acids of soybean meals were partially replaced by industrially manufactured amino acids (forming a low-protein feed), the carbon and water-consumption footprints in France were lowered by 0.41 t-CO2/t-feed and 100 m3/t-feed, respectively. The low-protein feed also incurred a 10% lower water-eutrophication footprint in comparison with the conventional feed. Based on these findings, if low-protein feed is widely used in Japan, the pig industry would reduce CO2 emissions and water consumption by 248,000 t-CO2/y and 68,000 km3/y, respectively.

Using ranirestat, an aldose reductase (AR) inhibitor, we investigated the relationship between sorbitol and fructose levels in the sciatic nerve and motor nerve conduction velocity (MNCV) in streptozotocin (STZ)-treated diabetic rats. Ranirestat inhibited rat and recombinant human AR with similar IC50 values and equipotently prevented sorbitol accumulation in rat erythrocytes and sciatic nerves in vitro. One week after STZ administration, sorbitol levels in rat erythrocytes and sciatic nerves significantly increased while MNCV decreased. Oral administration of ranirestat (0.03 – 1.0 mg/kg per day) for 3 weeks dose-dependently decreased the elevated sorbitol and fructose levels in the rat sciatic nerves without affecting blood glucose level. Particularly, at doses of 0.1 mg/kg per day or higher, ranirestat normalized both sorbitol and fructose levels in the sciatic nerves of STZ-treated rats. Ranirestat (0.1 – 1.0 mg/kg per day) also improved the STZ-induced decrease in MNCV in a dose-dependent manner. This improvement correlated with the decrease of sorbitol and fructose levels in the rat sciatic nerves. These findings indicate that ranirestat improves MNCV via normalization of sorbitol and fructose accumulation in the sciatic nerve. Keywords:: ranirestat, aldose reductase inhibitor, sorbitol, fructose, motor nerve conduction velocity (MNCV)

Ranirestat (AS-3201) is a novel aldose reductase (AR) inhibitor with potentially beneficial effects on diabetic sensorimotor polyneuropathy. In this study, we performed a kinetic analysis to determine the mode of inhibition of ranirestat on AR and investigated the effects of ranirestat on sorbitol levels in the sciatic nerves and lens of streptozotocin (STZ)-diabetic rats. We also evaluated the effects on motor nerve conduction velocity (MNCV) in STZ-diabetic rats. Kinetic analyses revealed that the ranirestat inhibition of AR is uncompetitive and reversible. In the sciatic nerve and lens of STZ-diabetic rats, single oral administration of ranirestat slightly reduced sorbitol levels. However, repeated oral administration of ranirestat for 5, 21, or 60 days enhanced the reducing effect of the ranirestat on sorbitol levels in the sciatic nerves and lens of STZ-diabetic rats with maximum effects after 21 days of treatment. Finally, repeated oral administration of ranirestat for 21 or 42 days dose-dependently improved the STZ-induced decrease in MNCV in STZ-diabetic rats. These findings demonstrate that repeated oral administration of ranirestat reduces sorbitol accumulation and improves MNCV in STZ-diabetic rats, indicating that ranirestat is an agent for the management of diabetic sensorimotor polyneuropathy. Keywords:: aldose reductase inhibitor, ranirestat (AS-3201), polyol pathway, motor nerve conduction velocity, streptozotocin-diabetic rat