Kinetic Characteristics of Neutralizing Antibody Responses Vary among Patients with COVID-19 / 生物医学与环境科学（英文）

Objective@#The coronavirus disease 2019 (COVID-19) pandemic continues to present a major challenge to public health. Vaccine development requires an understanding of the kinetics of neutralizing antibody (NAb) responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).@*Methods@#In total, 605 serum samples from 125 COVID-19 patients (from January 1 to March 14, 2020) varying in age, sex, severity of symptoms, and presence of underlying diseases were collected, and antibody titers were measured using a micro-neutralization assay with wild-type SARS-CoV-2.@*Results@#NAbs were detectable approximately 10 days post-onset (dpo) of symptoms and peaked at approximately 20 dpo. The NAb levels were slightly higher in young males and severe cases, while no significant difference was observed for the other classifications. In follow-up cases, the NAb titer had increased or stabilized in 18 cases, whereas it had decreased in 26 cases, and in one case NAbs were undetectable at the end of our observation. Although a decreasing trend in NAb titer was observed in many cases, the NAb level was generally still protective.@*Conclusion@#We demonstrated that NAb levels vary among all categories of COVID-19 patients. Long-term studies are needed to determine the longevity and protective efficiency of NAbs induced by SARS-CoV-2.

Differential response to pegylated interferon plus ribavirin combination therapy in chronic hepatitis C and HIV/HCV co-infected patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the potential differences in response to pegylated interferon (Peg-IFN) plus ribavirin (RBV) combination therapy in patients with hepatitis C virus (HCV) mono-infection and human immunodeficiency virus (HIV)/HCV co-infection.</p><p><b>METHODS</b>Seventy HIV/HCV patients and sixty HCV patients, were administered a 48-week course of Peg-IFN + RBV. The HCV load was tested by the COBAS automatic viral load analysis system (lower limit of quantification = 15 IU/ml) at treatment weeks 0 (baseline), 4, 12, 24, and 48 and at week 24 after drug withdrawal. The patients were also genotyped by sequencing for the host-encoded interleukin (IL)-28B single nucleotide polymorphisms (SNPs) related to HCV Peg-IFN + RBV therapy outcome: rs8099917, rs12979860 and rs12980275. In addition, the HCV-encoded NS5B gene region was genotyped by nested-PCR and sequencing followed by BLAST searching of the Los Alamos National Laboratory HCV database. The significance of between-group differences in response to therapy and roles of SNPs were evaluated by statistical analyses.</p><p><b>RESULTS</b>The ratio of sustained virological response (SVR) was significantly lower in the HIV/HCV co-infected patients than the HCV mono-infected patients (32.9% vs. 71.7%; P less than 0.001). While the HIV/HCV co-infected patients did not show a significant difference in SVR ratio achieved between individuals infected with the HCV-1 genotype and the non-HCV-1 genotype (30.8% vs. 33.3%; P = 1.000), the HCV mono-infected patients did (86.1% vs. non 50.0%, P = 0.002). Moreover, the SVR ratio was higher in the HCV-1 genotype HCV mono-infected patients than in the HIV/HCV-1 genotype co-infected patents (30.8% vs. 86.1%; P less than 0.001). The different IL-28B genotypes were not significantly correlated to the PEG-IFN+RBV therapy response of either HCV mono-infected patients or HIV/HCV co-infected patients (P more than 0.05).</p><p><b>CONCLUSION</b>HCV mono-infected patients respond better to Peg-IFN + RBV therapy than HIV/HCV co-infected patients. The HCV-1 genotype may promote this therapy response in HCV mono-infected patients, but the IL-28B genotypes appear to play no significant role.</p>

Gene copy number, mRNA transcription and protein expression of PD-1 gene in primary hepatocarcinoma patients / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the gene copy number, mRNA transcription and protien expression of programmed cell death 1 (PD-1) gene in primary hepatocellular carcinoma (PHC) patients and normal control individuals (NC) who are anti-HBs positive, and to investigate the variations in PD-1 gene copy numbers and its relationship with PHC.</p><p><b>METHODS</b>Real-time PCR was adopted to detect the PD-1 gene copy numbers and their mRNA expressions in peripheral blood mononuclear cells (PBMCs) from 24 samples of PHC patients and 26 of NC. Protein expression level of PD-1 on CD8+ T was analyzed by flow cytometry.</p><p><b>RESULTS</b>In terms of number of PD-1 gene copy numbers, the percentage of cases of haploid (single) was 34.62% and 4.17% in PHC group and control group respectively while the percentage of cases of diploid (double) was 61.54% and 95.83% respectively. The difference between the two was statistically significant (chi2 = 7.639, P = 0.006). The rate of cases with double PD-1 gene copy numbers was found to be higher in patients with PHC than in control group. It was also found that the average expression of PD-1 mRNA was 2.35E-03 in control group and 1.23E-03 in PHC group. The expression level was significant lower in PHC group than that in control group when compared by using Mann-whitey technic (U = 153, P = 0.009). Furthermore, the frequency of PD-1 protein expression on CD8+ T cells was 3.72 +/- 0.32 in control group and 16.13 +/- 1.68 in PHC group. The level of PD-1 mRNA expression was higher in PHC and significant differences was shown between two groups (t = -7.073, P = 0.000).</p><p><b>CONCLUSIONS</b>Our study suggests that the variation in PD-1 gene copy number may trigger primary hepatocellular carcinoma to HBV carriers. The relationship between the variation of PD-1 gene copy numbers and its association with primary hepatocellular carcinoma is worth further focus.</p>

Genetic diversity analysis of Penicillium marneffei isolated from AIDS patients in Guangdong, China using randomly amplified polymorphic DNA / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Penicillium marneffei (P. marneffei) is an emerging pathogenic fungus that can cause invasive mycosis in patients with AIDS. The epidemiological features of P. marneffei infection in AIDS patients in Guangdong province remain unclear so far. This study aimed to investigate the genetic diversity within a population of 163 P. marneffei isolates obtained from AIDS patients and search for the dominant clinical strains in Guangdong province.</p><p><b>METHODS</b>One hundred and sixty-three P. marneffei isolates obtained from AIDS patients in Guangdong province during January 2004 and December 2009 were studied by randomly amplified polymorphic DNA (RAPD) using two random primers (H2 and H22). The degree of similarity between samples was calculated through similarity coefficients from RAPD fragment data and the dendrogram was assessed using the unweighted pair group method with arithmetic mean (UPGMA).</p><p><b>RESULTS</b>Two primers showed a high degree of discrimination and good stability. Primer H2 yielded eight different patterns (H2-1 to H2-8) among 163 isolates with the discriminatory power being 0.413. Primer H22 identified seven types (H22-1 to H22-7) among 163 isolates with the discriminatory power being 0.467. Genetic similarity coefficients based on RAPD data among 163 P. marneffei isolates ranged from 0.681 to 0.957, 61.96% of which were no less than 0.83. The discriminatory power of the two primers was 0.524. One hundred and sixty-three P. marneffei isolates were clustered into nine distinct groups (groups I to IX) at the similarity coefficient value of 0.83 and group I was the most common, including 101 strains (61.96%).</p><p><b>CONCLUSION</b>The RAPD analyses could provide important information as to the degree of genetic diversity and the relationship among clinical P. marneffei isolates, revealing genetic polymorphism and dominant strains.</p>

Hepatitis B virus (HBV) mutation in enhancer I (HBV Enh I)/X-promoter and the relationship between chronic HBV-related disease spectrum / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the hepatitis B virus (HBV) mutation in the Enhancer I (HBV Enh I)/X-promoter and to analysis the relationship between chronic HBV-related disease spectrum.</p><p><b>METHODS</b>275 patients were enrolled in this study, including 100 cases of chronic hepatitis B (CHB), 74 cases of liver cirrhosis (LC), 101 cases of hepatocellular carcinoma (HCC), grouping by different HBV genotypes, using semi-nested PCR amplification of HBV Enh I/X-promoter and sequencing DNA, the mutations were determined by alignment to HBV reference sequence, the data was compared by chi2 test and analyzed by multivariate logistic regression.</p><p><b>RESULTS</b>(1) Genotyping results: 61.48% (158/257) were infected with HBV genotype B, including 70 cases of CHB, 36 cases of LC and 52 cases of HCC; 38.52% (117/257) were infected with HBV genotype C, including 30 cases of CHB, 38 cases of LC and 49 cases of HCC. (2) In the patients were infected with HBV genotype B, A1123Y mutation in LC was significantly higher than in CHB (30.56% vs. 8.58%, chi2 = 8.533, P = 0.005, A = 4.693, 95% CI [1.567-14.056]), HCC was significantly higher than in CHB (28.85% vs. 8.58%, chi2 = 8.607, P = 0.003, A = 4.324,95% CI [1.544-2.109]); A1317G mutation in HCC was significantly higher than in CHB (30.77% vs. 7.14%, chi2 = 11.687, P = 0.001, A = 5.778, 95% CI [1.955-17.076]). In the patients were infected with HBV genotype C, T1323C mutation in HCC was significantly higher than in CHB (30.61% vs. 6.67%, chi2 = 6.318, P = 0.12, A = 6.176, 95% CI [1.301-29.331]). (3) Multivariate regression analyses showed that A1317G (OR = 5.706, 95% CI [1.770-18.837], P = 0.004) and T1323C (A = 5.810, 95% CI [1.114-30.306], P = 0.037) mutation were risk factors for HCC.</p><p><b>CONCLUSION</b>HBV Enh I/X-promoter mutations were associated with the development of LC and HCC, the mutations can help to predict the occurrence of LC and HCC.</p>

Analysis of hepatitis C virus (HCV) subtypes in HIV/HCV co-infected and HCV mono-infected individuals in Guangdong province / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the transmission routes, genotypes/subtypes distribution and genetic character of HCV in HIV/HCV co-infected and HCV mono-infected individuals in Guangdong Province.</p><p><b>METHODS</b>Reverse transcription (RT) nested PCR was performed to amplify the HCV NS5B gene region from 95 HIV/HCV co-infected and 99 HCV mono-infected individuals lived in Guangdong province. The PCR products were then sequenced for HCV subtyping. Genetic analysis was done by MEGA4 software.</p><p><b>RESULTS</b>(1) HIV/HCV co-infected individuals infected HCV mostly through injection drug use (IDU, 78.9%), the HCV subtypes were identified as 6a (53.7%), 3a (17.9%), 1b (15.8%), 3b (11.6%) and 1a (1.0%) respectively, the genetic distance within subtype 1b was longer than those within other subtypes, the predominant HCV subtype in HIV/HCV co-infected individuals infected through IDU was 6a (60.0%). (2) HCV mono-infected individuals infected HCV mostly through blood or blood products transfusions (80.8%), the HCV subtypes were identified as 1b (67.7%), 6a (17.2%), 3a (6.1%), 2a (5.0%), 3b (2.0%), 4a (1.0%) and 5a (1.0%) respectively, the genetic distance within subtype 1b was also longer than those within other subtypes, the predominant HCV subtype in HCV mono-infected individuals infected through blood or blood products transfusions was 1b (76.2%).</p><p><b>CONCLUSION</b>The diversity of HCV subtypes in HIV/HCV co-infected and HCV mono-infected individuals in Guangdong Province was high, both the major transmission route and HCV subtype between HIV/HCV co-infected individuals and HCV mono-infected individuals were different.</p>

Study on the copy numbers and mRNA expression levels of the programmed death-1 gene in chronic hepatitis B patients / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the copy numbers and mRNA expression levels of the Programmed Death-1 gene in chronic hepatitis B patients and to analyze the differences of the copy numbers and mRNA expression levels of the gene in patients with different clinical outcomes.</p><p><b>METHODS</b>Real time PCR was adopted to detect the PD-1 gene copy numbers and their mRNA expressions in peripheral blood mononuclear cells (PBMCs) from 27 samples from healthy donors in Control group, 31 samples from chronic asymptomatic HBV carriers (ASC, n=31), 19 samples from chronic severe hepatitis B patients (CSH, n=19) and 29 samples from Primary hepatitis B Virus-related hepatocarcinoma (PHC, n=29). The differences and relationship of copy numbers and their mRNA expression levels among those groups were compared and analyzed by adopting Chi-square test and Rank sum test.</p><p><b>RESULTS</b>PD-1 gene copy number deviated from 0 copy to 3 copies among all the 106 samples. In control group, ASC group, CSH group and PHC group, the percentages of cases of haploid (single) were 37.0%, 35.5%, 26.3% and 6.9%, respectively, the percentages of cases of diploid (double) were 55.5%, 58.0%, 63.2% and 82.8%, respectively, and the percentages of cases of triploid (triple) were 3.7%, 6.5%, 10.5% and 10.3%, respectively. The percentage of cases of polyploid (diploid and triploid) in control group, ASC group, CSH group and PHC group were 59.3%, 64.5%, 73.7% and 93.1%, respectively. The different distribution of PD-1 gene copy number of polyploid was significant in total samples (x2=9.583, P<0.05). Compared with Control Group and ASC group, the percentage of cases of polyploid in PHC group was lower with the x2 equals to 8.985 and 7.215 respectively and both with P less than 0.05. The difference between the two groups was statistically significant. The mean PD-1 gene copy numbers for these four groups were 1.59+/-0.63, 1.70+/-0.52, 1.84+/-0.60 and 2.00+/-0.37 while the median were 0.002 54, 0.002 72, 0.002 55 and 0.001 33 respectively. Except the control group, there was a uptrend in the other three groups while PD-1 gene mRNA expression presented a downtrend. The mean of PD-1 gene copy numbers of 2 and their mRNA expression levels were 19.59, 32.57 and 33.22 for PHC, CSH and ASC groups among which PHC group had the lowest value, there was significant differences found in the comparison with F=5.395 and P<0.05.</p><p><b>CONCLUSION</b>PD-1 gene copy numbers and their mRNA expression levels were different in chronic HBV infected patients with different transformation. It is valuable to follow up the patients with more than 1 copy number of PD-1 gene in long term.</p>

Excretory/secretory antigens from Clonorchis sinensis induces hepatic fibrosis in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of excretory/secretory antigens from Clonorchis sinensis (CsESAs) in hepatic fibrosis induced by C. sinensis infection in rats and explore the possible mechanism.</p><p><b>METHODS</b>CsESAs was collected from adult C. sinensis cultured in sterile condition for 12 h and injected intraperitoneally in Wistar rats. Masson staining was used to observe the changes in the hepatic collagen fiber after the injection. HE staining and immunofluorescence staining were performed to detect the expression of alpha-smooth muscle actin (alpha-SMA) to examine the proliferation and the activity of hepatic stellate cells. The specific antibody titer of CsESAs was determined using enzyme-linked immunosorbent assay to investigate the role of the antigen-antibody complex in the development of hepatic fibrosis.</p><p><b>RESULTS</b>After intraperitoneal injection of CsESAs, obvious hepatic fibrosis and hepatic stellate cell proliferation and activation were observed in the rat livers. The severity of the hepatic fibrosis was associated with the dose of CsESAs injected, whereas the titer of the specific antibody against CsESAs showed no direct relation to the hepatic fibrosis.</p><p><b>CONCLUSION</b>Intraperitoneal injection of CsESAs can cause hepatic stellate cell activation and hepatic fibrosis in rats, but the antigen-antibody complex does not seem to play the key role in the activation of the hepatic stellate cells.</p>