Consecutive positive nucleic acid tests in COVID-19 patients: a retrospective cohort study in Fangcang hospitals, Shanghai.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) spread rapidly in Shanghai in February 2022. Patients with asymptomatic and mild symptoms were admitted to Fangcang shelter hospitals for centralized quarantine. METHODOLOGY: A total of 5,217 non-severe patients hospitalized in the Longyao Fangcang and Shilong Fangcang hospitals were included in the study. Demographic and clinical characteristics, comorbidity, exposure history, treatment and disease duration were analyzed. Univariate analysis and binomial logistic regression analysis were performed to identify the factors influencing nucleic acid change from positive to negative over 14 days. RESULTS: Consecutive positive nucleic acid test results (days) were significantly associated with advanced age (OR = 1.343, 95% CI 1.143 to 1.578, p < 0.001), smoking (OR = 0.510, 95% CI 0.327 to 0.796, p = 0.003) and vaccination (OR = 0.728, 95% CI 0.641 to 0.827, p < 0.001). However, there was no significant difference between asymptomatic and mild symptomatic patients (p = 0.187). In univariate analysis, comorbidities including diabetes, hypertension, cardiovascular system, malignant tumors, autoimmune diseases and cerebral apoplexy were associated with consecutive positive nucleic acid test results, but there was no significant difference in binomial logistics regression analysis. CONCLUSIONS: Aging and comorbid conditions lead to the prolongation of positive nucleic acid test results for several days. Improving vaccination coverage is beneficial for prevention and control of the epidemic. The management and treatment methods of Shanghai Fangcang shelter hospitals had important referential significance, which can provide valuable guidance for the prevention and control of the COVID-19 epidemic in the future.

Anticolitic Effect of Berberine in Rat Experimental Model: Impact of PGE2/p38 MAPK Pathways.

Berberine (BER), a natural isoquinoline alkaloid, has been demonstrated to have appreciable anticolitis effects. Nevertheless, the protective mechanism of BER in ulcerative colitis (UC) is barely understood. The present study was aimed at exploring the therapeutic efficacy of BER on UC in experimental colitis rat model. Rats were orally administered with BER for seven days at low and high doses (25 and 50 mg/kg/day) before AcOH intracolonic instillation. BER significantly retrieved colon inflammation and mucosal damage indicated by inhibition of macroscopic score and lessened the levels of inflammatory biomarkers (IL-1ß, IL-6, TNF-α, MPO, and PGE2). Notable downregulation of mRNA expression of p38 MAPK and increased protein expression of TGF-ß were achieved by BER treatment. The anti-inflammatory potential of BER was supported by the histopathological screening of colon mucosa. In addition, BER restored colonic antioxidant capacity through elevation of GSH level and antioxidant enzymatic activities (SOD, CAT, GPx, and GR) together with reductions of both MDA and NO levels. Marked downregulation of Nos2 mRNA expression is accompanied by increased Nrf2 and Hmox-1 expressions in colon specimens treated by BER. Furthermore, BER exhibited noticeable antiapoptotic activities through decreasing proapoptotic proteins (Bax and caspase-3) and lessening antiapoptotic Bcl-2 protein in the colon mucosa. Based on these findings, BER may improve colitis markedly which may be mediated by its striking antioxidant, anti-inflammatory, and antiapoptotic properties.