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1.
Preprint in English | bioRxiv | ID: ppbiorxiv-258376

ABSTRACT

A novel coronavirus disease (COVID-19) caused by SARS-CoV-2 has been pandemic worldwide. The genetic dynamics of quasispecies afford RNA viruses a great fitness on cell tropism and host range. However, no quasispecies data of SARS-CoV-2 have been reported yet. To explore quasispecies haplotypes and its transmission characteristics, we carried out single-molecule real-time (SMRT) sequencing of the full-length of SARS-CoV-2 spike gene within 14 RNA samples from 2 infection clusters, covering first-to third-generation infected-patients. We observed a special quasispecies structure of SARS-CoV-2 (modeled as One-King): one dominant haplotype (mean abundance ~70.15%) followed by numerous minor haplotypes (mean abundance < 0.10%). We not only discovered a novel dominant haplotype of F1040 but also realized that minor quasispecies were also worthy of attention. Notably, some minor haplotypes (like F1040 and currently pandemic one G614) could potentially reveal adaptive and converse into the dominant one. However, minor haplotypes exhibited a high transmission bottleneck (~6% could be stably transmitted), and the new adaptive/dominant haplotypes were likely originated from genetic variations within a host rather than transmission. The evolutionary rate was estimated as 2.68-3.86 x 10-3 per site per year, which was larger than the estimation at consensus genome level. The One-King model and conversion event expanded our understanding of the genetic dynamics of SARS-CoV-2, and explained the incomprehensible phenomenon at the consensus genome level, such as limited cumulative mutations and low evolutionary rate. Moreover, our findings suggested the epidemic strains may be multi-host origin and future traceability would face huge difficulties.

2.
Preprint in English | medRxiv | ID: ppmedrxiv-20042382

ABSTRACT

BackgroundA pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spreading over the world. However, the viral dynamics, host serologic responses, and their associations with clinical manifestations, have not been well described in prospective cohort. MethodsWe conducted a prospective cohort and enrolled 67 COVID-19 patients admitting between Jan 26 and Feb 5, 2020. Clinical specimens including nasopharyngeal swab, sputum, blood, urine and stool were tested periodically according to standardized case report form with final follow-up on February 27. The routes and duration of viral shedding, antibody response, and their associations with disease severity and clinical manifestations were systematically evaluated. Coronaviral particles in clinical specimens were observed by transmission electron microscopy (TEM). ResultsThe median duration of SARS-CoV-2 RNA shedding were 12 (3-38), 19 (5-37), and 18 (7-26) days in nasopharyngeal swabs, sputum and stools, respectively. Only 13 urines (5.6%) and 12 plasmas (5.7%) were viral positive. Prolonged viral shedding was observed in severe patients than that of non-severe patients. Cough but not fever, aligned with viral shedding in clinical respiratory specimens, meanwhile the positive stool-RNA appeared to align with the proportion who concurrently had cough and sputum production, but not diarrhea. Typical coronaviral particles could be found directly in sputum by TEM. The anti-nucleocapsid-protein IgM started on day 7 and positive rate peaked on day 28, while that of IgG was on day 10 and day 49 after illness onset. IgM and IgG appear earlier, and their titers are significantly higher in severe patients than non-severe patients (p<0.05). The weak responders for IgG had a significantly higher viral clearance rate than that of strong responders (p= 0.011). ConclusionsNasopharyngeal, sputum and stools rather than blood and urine, were the major shedding routes for SARS-CoV-2, and meanwhile sputum had a prolonged viral shedding. Symptom cough seems to be aligned with viral shedding in clinical respiratory and fecal specimens. Stronger antibody response was associated with delayed viral clearance and disease severity. Summary boxesO_ST_ABSWhat is already known on this topicC_ST_ABSAs a newly appearing infectious disease, early efforts have focused on virus identification, describing the epidemiologic characteristics, clinical course, prognostics for critically illed cases and mortality. Among COVID-19 cases reported in mainland China (72 314 cases, updated through February 11, 2020), 81% are mild, 14% are severe, and 5% are critical. The estimated overall case fatality rate (CFR) is 2.3%. Some case series reported had shown that SARS-CoV-2 could shed in upper/lower respiratory specimens, stools, blood and urines of patients. However, important knowledge gaps remain, particularly regarding full kinetics of viral shedding and host serologic responses in association with clinical manifestations and host factors. What this study addsThe incubation period has no change after spreading out of Wuhan, and has no sex or age differences, however, children had prolonged incubation period. Due to early recognition and intervention, COVID-19 illness of Chongqing cohort is milder than that of Wuhan patients reported. This prospective cohort study on SARS-CoV-2 infection shows clearly that the viral and serological kinetics were related in duration of infection, disease severity, and clinical manifestations of COVID-19. Our data demonstrate that nasopharyngeal, sputum and stools are major shedding routes for SARS-CoV-2, and stronger NP antibody response is associated with delayed viral clearance and disease severity.

3.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-822570

ABSTRACT

@#Objective    To investigate the protective effect and mechanism of curcumin on lipopolysaccharide (LPS)-induced acute lung injury. Methods    Totally 24 SD rats were randomly divided into a control group, a LPS group and a LPS+curcumin group (n=8 in each group). The degree of lung injury (oxygen partial pressure, wet/dry ratio, pathological scores) and inflammatory levels [tumor necrosis factor (TNF)-α, interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, Toll-like receptor 4 (TLR4), mobility group box 1 protein (HMGB1) expression] of the lung were detected in different groups. Results    Oxygen partial pressure was significantly lower in the LPS group than that in the control group (P<0.05), while wet/dry ratio, pathological scores and expression levels of TNF-α, IL-6, MCP-1, TLR4 and HMGB1 were significantly higher in the LPS group than those in the control group (P<0.05). Compared with the LPS group, curcumin significantly reduced wet/dry ratio, pathological scores and expression levels of TNF-α, IL-6, MCP-1, TLR4 and HMGB1 in the LPS+curcumin group (P<0.05), while it significantly improved oxygen partial pressure (P<0.05). Conclusion    Curcumin might protect LPS-induced acute lung injury through inhibition of TLR4-HMGB1-inflammation pathway.

4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-733531

ABSTRACT

Objective To explore the treatment experience and efficacy of precise surgery for hepatic caudate lobe involved lesions.Methods The retrospective cross-sectional study was conducted.The clinicopathological data of 127 patients with hepatic caudate lobe involved lesions who were admitted to Hunan Provincial People's Hospital between January 2012 and December 2016 were collected,including 71 of malignant tumors,52 of benign lesions and 4 of other diseases.Anatomical hepatectomy was performed in patients via left approach,right approach,anterior approach,left combined with right approach,left and right combined with anterior approach,left and right combined with para-liver hanging tape approach,anterior combined with left approach,retrograde approach according to their conditions.Observation indicators:(1) intraoperative and postoperative recovery situations;(2) follow-up and survival situations.Follow-up using outpatient examination and telephone interview was done to detect postoperative survival of patients up to February 2018.Measurement data with normal distribution were represented as (x)±s.Measurement data with skewed distribution were described as M (range).Kaplain-Meier method was used to calculate survival rate.Results (1) Intraoperative and postoperative recovery situations:all the 127 patients underwent successful operation without perioperative death,including 111 of open surgery and 16 of laparoscopic surgery.Of 127 patients,single total caudate lobectomy and partial caudate lobectomy were performed in 2 and 13 patients,single hepatic segmentectomy combined with total caudate lobectomy,double hepatic segmentectomy combined with total caudate lobectomy,hepatic trisegmentectomy combined with total caudate lobectomy,left hemitectomy combined with total caudate lobectomy,left hepatic trilobectomy combined with total caudate lobectomy,right hemitectomy combined with total caudate lobectomy,right hepatic trilobectomy combined with total caudate lobectomy were performed in 6,4,5,1,1,30,3 patients respectively,single hepatic segmentectomy combined with partial caudate lobectomy,double hepatic segmentectomy combined with partial caudate lobectomy,left hemitectomy combined with partial caudate lobectomy,left hepatic trilobectomy combined with partial caudate lobectomy,right hemitectomy combined with partial caudate lobectomy,right hepatic trilobectomy combined with partial caudate lobectomy were performed in 3,3,41,2,5,8 patients respectively,including 78 via left approach,29 via right approach,2 via anterior approach,7 via left combined with right approach,2 via left and right combined with anterior approach,6 via left and right combined with para-liver hanging tape approach,1 via anterior combined with left approach,2 via retrograde approach.The operation time,time of first hepatic hilum occlusion,volume of intraoperative blood loss and duration of postoperative hospital stay were 285 minutes (range,188-670 minutes),47 minutes(range,30-150 minutes),294 mL(range,20-2 500 mL) and 10 days (range,6-27 days) respectively.Thirty-four patients had postoperative complications,including 21 with abdominal ascites,20 with pleural effusion,6 with incisional infection,5 with hemorrhage,4 with bile leakage,2 with pulmonary infection (1 patient combined with multiple complications).One patient underwent reoperation after ineffective conservative treatment for hemorrhage within postoperative 24 hours and other 33 were cured by conservative treatment.(2) Follow-up and survival situations:of 127 patients,124 including 68 of malignant tumors and 56 of non-malignant tumors were followed up for 2-71 months with a median time of 33 months.During the follow-up,1-,3-,5-year overall survival rates were 83.1%,63.4%,22.5% in 68 patients with malignant tumors,89.3%,71.4%,57.1% in 28 patients with hilar cholangiocarcinoma and 76.9%,46.2%,23.1% in 26 with hepatocellular carcinoma.All the 56 patients with non-malignant tumors survived well.Conclusions Anatomical hepatectomy using precise surgery is safe and feasible.Preoperative precise evaluation and surgical procedure design,intraoperative vascular control and surgical plane mastering are keys to success.

5.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-489770

ABSTRACT

Objective To investigate the safety and short-term effect of anatomical hepatectomy for the treatment of hepatolithiasis with the caudate lobe as the sole remnant liver.Methods The clinical data of 1 patient with hepatolithiasis combined with liver atrophy-hypertrophy syndrome who was admitted to the Hunan Provincial People's Hospital in April 2014 were retrospectively analyzed.The stones were located in the left and right liver, the involved liver became fibroatrophy, and the hepatic caudate lobe not containing stones became hypertrophy.The body surface area of the patient was 1.65 m2 , standard total liver volume was 1 167.63 mL.According to the result of CT, expected residual liver volume after hepatectomy was 706.12 mL, and the ratio of residual liver volume over the standard total liver was 60.47%.The radio of residual liver volume over the body mass index was 1.21%.The patient received the second exploration of common bile ducts, hepatectomy with the caudate lobe as the sole remnant liver and T tube drainage.The follow-up including recurrence of calculus was performed by outpatient examination and telephone interview up to April 2015.Results The patient underwent caudate lobe as the sole remnant liver following anatomical hepatectomy successfully without blood transfusion.The operation time and volume of intraoperative blood loss were 380 minutes and 350 mL.The peritoneal drainage tube was removed at postoperative day 2 and the patient was discharged at postoperative day 8 with a good recovery of liver function.The postoperative pathological examination showed that there were focal biliary epithelial papillary hyperplasia combined with light-medium atypical hyperplasia and no canceration.The T tube cholangiography two month later showed that there were unobstructed lower bile duct and no residual intra-and extra-hepatic stones.The liver function was normal.Then T tube was removed and patient resumed normal life.During the 1-year follow-up, no chills and fever, jaundice and abdominal pain occurred, no calculus was detected by B-ultrasonography, and computed tomography reexamination showed that remnant liver volume was increased and no intra-and extra-hepatic bile duct stones were detected.Conclusion Anatomical hepatectomy for the treatment of hepatolithiasis with the caudate lobe as the sole remnant liver is safe and feasible, with a good curative effect.

6.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-555532

ABSTRACT

Objective To investigatethe changes of serum IL-12 level and Th balance of chronic hepatitis B (CHB) patients in the course of lamivudine therapy and the related significance. Methods According to the differ ent responses to lamivudine therapy, patients were divided into three groups: group I ( n = 10), HBeAg positive CHB and complete response group; group Ⅱ (n = 10), HBeAg positive CHB and non-complete response group;group Ⅲ ( n = 5), HBeAg negative CHB group. Sera were collected from patients with chronic hepatitis B before and after lamivudine therapy and healthy blood donors. Then serum IL-12, IFN?, and IL-4 levels were measured by ELISA method. The ratio of IFN?/IL-4 was selected as the marker of Th balance after comparison with that of the normal control. Results Before therapy, serum IL-12 level in chronic hepatitis B patients was lower than that of the healthy blood donors, and Th balance tendency was to Th2 direction. After lamivudine therapy, serum IL-12 level was increased. The highest point of IL-12 was observed in complete response group at the third month after therapy.The tendency of Th balance was to Th 1 direction in complete response group and to Th 2 direction in non-complete response group and HBeAg negative group. Conclusion After lamivudine therapy, the immunity response to HBV of chronic hepatitis B patients can be recovered. The response degree to therapy is associated with the level of serum IL-l2 and Th balance recovery level after lamivudine therapy. Serum IL-12 level may be an appropriable marker to predict the effect of lamivudine therapy in earlier period of the whole course. The recovery of Th balance is the assurance of complete response.

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