SARS-CoV-2 BA.2 (Omicron) variant infection in pediatric liver transplanted recipients and cohabitants during 2022 Shanghai outbreak: a prospective cohort.

BACKGROUND: The Omicron variant BA.2 was the dominant variant in the COVID-19 outbreak in Shanghai since March 2022. We aim to investigate the characteristics of SARS-CoV-2 Omicron variant infection in pediatric liver-transplanted recipients. METHODS: We conducted a single-center, prospective, observational, single-arm study. We enrolled pediatric liver-transplanted patients infected with the Omicron variant BA.2 from March 19th to October 1st, 2022 and analyzed their demographic, clinical, laboratory, and outcome data. The management of COVID-19 was conducted according to the 9th trial edition of the Chinese guideline. The immunosuppressive therapy was tailored considering the patients' infection developments and liver functions. RESULTS: Five children were included. The primary diseases included Niemann-Pick disease, propionic acidemia, decompensated cirrhosis, biliary atresia, and Crigler-Najjar syndrome type I. All of the patients were onset with fever before or when getting RNA-positive results at the age of 3 (Range: 1-13) years. The infection duration was 29 (Range: 18-40) days. Three and two children were diagnosed with mild and moderate COVID-19 respectively. Two patients were tested RNA-positive within 14 days after having been tested negative. The immunosuppressants were paused or extenuated in four patients. Eight of all nine cohabitants were injected with at least two doses of inactivated SARS-CoV-2 vaccine. The disease courses were significantly longer than the patients (P < 0.05). CONCLUSIONS: Post-transplant immunosuppression slows down the virus clearance and increases the risk of relapse but does not affect symptom duration or infection severity in pediatric patients. Patients can usually gain a favorable outcome and prognosis by extenuating immunosuppressants.

Research Trends in Lung Organoids: Bibliometric Analysis and Visualization (preprint)

Background Lung organoids have emerged as a promising tool for studying lung development, function, and disease pathology. The present study aimed to analyze the current status and development trends of lung organoid research over the past years, present visual representations, and provide references for future research directions using bibliometric analysis.Methods Information on articles on lung organoids extracted from the Web of Science Core Collection, such as year of publication, journal, country, institution, author, and keywords, was analyzed. R, VOSviewer, and SCImago Graphica were used to visualize publication trends, co-authorship analysis, co-occurrence analysis, and hotspot evolution.Results The number of global publications has increased from 1 in 2011 to 512 in 2022. The cell produced the highest number of citations (2,069 citations). The United States (6,694 citations and 177 publications), University Medical Center Utrecht (2,060 citations and 9 publications), and Clevers H (2,570 citations and 15 publications) were the most influential countries, institutions, and authors, respectively. Co-occurrence cluster analysis of the top 54 keywords formed four clusters: (1) pulmonary fibrosis (PF), (2) lung cancer, (3) cystic fibrosis (CF), (4) coronavirus disease 2019 (COVID-19) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).Conclusion Organoid technology undoubtedly played an important role in the study of COVID-19, but with the passing of the COVID-19 epidemic, the research focus may return to refractory lung diseases such as PF, CF, and lung cancer. Standardized culture, living biobanks, and multimodal model systems for lung disease may be the future research directions in the field of lung organoids.

Risks, characteristics, and control strategies of disinfection-residual-bacteria (DRB) from the perspective of microbial community structure.

The epidemic of COVID-19 has aroused people's particular attention to biosafety. A growing number of disinfection products have been consumed during this period. However, the flaw of disinfection has not received enough attention, especially in water treatment processes. While cutting down the quantity of microorganisms, disinfection processes exert a considerable selection effect on bacteria and thus reshape the microbial community structure to a great extent, causing the problem of disinfection-residual-bacteria (DRB). These systematic and profound changes could lead to the shift in regrowth potential, bio fouling potential, as well as antibiotic resistance level and might cause a series of potential risks. In this review, we collected and summarized the data from the literature in recent 10 years about the microbial community structure shifting of natural water or wastewater in full-scale treatment plants caused by disinfection. Based on these data, typical DRB with the most reporting frequency after disinfection by chlorine-containing disinfectants, ozone disinfection, and ultraviolet disinfection were identified and summarized, which were the bacteria with a relative abundance of over 5% in the residual bacteria community and the bacteria with an increasing rate of relative abundance over 100% after disinfection. Furthermore, the phylogenic relationship and potential risks of these typical DRB were also analyzed. Twelve out of fifteen typical DRB genera contain pathogenic strains, and many were reported of great secretion ability. Pseudomonas and Acinetobacter possess multiple disinfection resistance and could be considered as model bacteria in future studies of disinfection. We also discussed the growth, secretion, and antibiotic resistance characteristics of DRB, as well as possible control strategies. The DRB phenomenon is not limited to water treatment but also exists in the air and solid disinfection processes, which need more attention and more profound research, especially in the period of COVID-19.