Duration of viral shedding of the Omicron variant in asymptomatic and mild COVID-19 cases from Shanghai, China

BackgroundThe Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), designated as a variant of concern by the World Health Organization, spreads globally and was confirmed as the cause of the Omicron wave of the coronavirus disease 2019 (COVID-19) pandemic in Shanghai, China. The viral shedding duration of Omicron variants needs to be determined. MethodsWe retrospectively analyzed 382 patients admitted to a shelter hospital for COVID-19. Of the patients, 8 patients were referred to a designated hospital, 100 were infected asymptomatic patients, and 274 patients had mild COVID-19. ResultsThe vaccination rates (including fully and boosted) in the asymptomatic and mild COVID-19 patients were 92.00% and 94.16%, respectively. Majority of the studied population showed a first reverse transcription-polymerase chain reaction cycle threshold (Ct) value of 20. For 2565 nasopharyngeal swabs from close or sub-close contacts, the Ct value gradually increased to 35 for 8 days, and the median duration of viral shedding time was 10 days after the first positive detection of the SARS-CoV-2 nuclei acid. ConclusionsQuantitative viral RNA load assays in COVID-19 (BA.2.2.1) close or sub-closed contacts could be used to prevent transmissions and control precautions.

Hypokalemia and Clinical Implications in Patients with Coronavirus Disease 2019 (COVID-19)

BACKGROUNDSARS-CoV-2 has caused a series of COVID-19 globally. SARS-CoV-2 binds angiotensin I converting enzyme 2 (ACE2) of renin-angiotensin system (RAS) and causes prevalent hypokalemia METHODSThe patients with COVID-19 were classified into severe hypokalemia, hypokalemia, and normokalemia group. The study aimed to determine the relationship between hypokalemia and clinical features, the underlying causes and clinical implications of hypokalemia. RESULTSBy Feb 15, 2020, 175 patients with COVID-19 (92 women and 83 men; median age, 46 [IQR, 34-54] years) were admitted to hospital in Wenzhou, China, consisting 39 severe hypokalemia-, 69 hypokalemia-, and 67 normokalemia patients. Gastrointestinal symptoms were not associated with hypokalemia among 108 hypokalemia patients (P > 0.05). Body temperature, CK, CK-MB, LDH, and CRP were significantly associated with the severity of hypokalemia (P<0.01). 93% of severe and critically ill patients had hypokalemia which was most common among elevated CK, CK-MB, LDH, and CRP. Urine K+ loss was the primary cause of hypokalemia. 1 severe hypokalemia patients was given 3 g/day, adding up to an average of 34 (SD=4) g potassium during hospital stay. The exciting finding was that patients responded well to K+ supplements when they were inclined to recovery. CONCLUSIONSHypokalemia is prevailing in patients with COVID-19. The correction of hypokalemia is challenging because of continuous renal K+ loss resulting from the degradation of ACE2. The end of urine K+ loss indicates a good prognosis and may be a reliable, in-time, and sensitive biomarker directly reflecting the end of adverse effect on RAS system.

Virulence gene detection and multi-locus sequence typing of Vibrio parahaemolyticus from patients in Ningbo,China / 中国人兽共患病学报

To investigated the toxin genes distribution and molecular characteristics of Vibrio parahaemolyticus from pa‐tients in Ningbo ,V .parahaemolyticus strains were collected from patients with food poisoning and diarrhea .Thermostable di‐rect hemolysin gene (tdh) and TDH‐related hemolysin gene (trh) were detected by polymerase chain reaction (PCR) .Molecu‐lar characteristics were acquired by multi‐locus sequence typing (MLST ) .Of 248 clinical strains were isolated from 2006 to 2012 .Forty‐eight strains were selected to detect virulence genes and MLST genotyping .Forty‐two isolates were detected as tdh+ and 11 isolates were detected as trh+ .There were 9 STs and one undifferentiated type in Ningbo clinical strains .Thirty‐two strains were classified into ST3 ,5 strains into ST265 and 3 strains into ST120 .ST265 was found in Ningbo strains com‐pared with strains from other regions of China .Strains with tdh+ accounted for the majority in Ningbo clinical strains .Twen‐ty‐five strains of ST3 clone were tdh+ /trh‐.There were 9 STs coexsited in Ningbo clinical strains .ST3 clone was dominant , followed by ST265 and ST120 .Strains with tdh+ /trh‐were dominant in the ST3 clone .The unique ST262 was found in Ning‐bo clinical strains .

Construtcion of Neisseria Gonorrhoeae Porin B Plasmid Recombinant and Its Expression in E.coli / 华中科技大学学报（医学）（英德文版）

Summary: A prokaryotic expression recombinant plasmid pET-PIB to express porin B (PIB) of Neisseria gonorrhoeae in E.coli DE3 was constructed in order to provide a basis of research in detection, prophylactic and therapeutic vaccine against the pathogen infection. The gene encoding PIB was amplified by PCR from Neisseria gonorrhoeae and cloned into prokaryotic expression plasmid pET-28a(+) to construct a pET-PIB recombinant, which was verified by restriction endonuclease and DNA sequencing. Protein PIB was expressed in E.coli DE3 induced with IPTG. The antigenicity of the expressed protein was evaluated by indirect ELISA. Rabbits were immunized with the protein and serum was collected after immunization. To assess the immunogenicity of the protein, the titer of serum to protein PIB was determined by ELISA. DNA sequence analysis showed that the nucleic acid sequence of PIB gene was 99.28 % of homology compared with that (NGPIB18) published in GenBank. A 41 kD fused protein was detected by SDS-PAGE and was proven to have reactivity with anti-PIB polyclonal antibody from mouse. A polyclonal antibody to PIB of 1:4000 titer determined by indirect ELISA was obtained from rabbit immunized with the purified product. Recombinant plasmid encoding PIB of Neisseria gonorrhoeae was constructed. Protein PIB with antigenicity and immunogenicity was successfully expressed.

Construction of prokaryotic expression plasmid of fusion protein including porin A and porin B of Neisseria gonorrhoeae and its expression in E. coli / 华中科技大学学报（医学）（英德文版）

In order to provide a rational research basis for clinical detection and genetic engineering vaccine, plasmid pET-28a (+) encoding both Porin gene PIA and PIB of Neisseria gonorrhoeae was constructed and a fusion protein in E. coli DE3 expressed. The fragments of PIA and PIB gene of Neisseria gonorrhoeae were amplified and cloned into prokaryotic expression plasmid pET-28a (+) with double restriction endonuclease cut to construct recombinant pET-PIB-PIA. The recombinant was verified with restriction endonuclease and sequenced and transformed into E. coli DE3 to express the fusion protein PIB-PIA after induced with IPTG. The results showed PIA-PIB fusion DNA fragment was proved correct through sequencing. A 67 kD (1 kD= 0.992 1 ku) fusion protein had been detected by SDS-PAGE. It was concluded that the fusion protein was successively expressed.