[HCV antigen detection method and clinical application].

Hepatitis C is distributed worldwide and possesses a hidden characteristic. The traditional methods of screening and diagnosis of hepatitis C infection commonly used in clinics are based on anti-HCV antibody and HCV RNA detection. Advances in HCV antigen detection technologies can apparently reduce the window period for anti-HCV antibodies, providing new clinical evidence for the early detection, diagnosis, and treatment of HCV infection. This article is a current review of HCV antigen detection methodologies, clinical applications, and detection strategies.

[Dynamic changes and influencing factors of HIV-1 DNA load in HIV-1 infected individuals under antiretroviral therapy].

Objective: To analyze the dynamic changes and influencing factors of HIV-1 DNA load in HIV-1 infected individuals under antiretroviral therapy (ART) in Dehong Dai and Jingpo autonomous prefecture, Yunnan province, and provide information support for the clinical use of HIV-1 DNA quantitative detection. Methods: The HIV infection cases in recent infection cohort from Dehong Center for Disease Control and Prevention during 2009-2018 were selected as study subjects. The dynamic curve of HIV-1 DNA load varrying with time was generated and logistic regression analysis was conducted to identify the risk factors for HIV-1 load in the recent follow up after ART and statistical analysis was performed by using SPSS 17.0. Results: Among the 113 HIV infection cases detected from the recent infection cohort, the recent HIV infection rate were 49.6%(56/113) males, sexual transmission cases and drug injection transmission cases accounted for 53.1% (60/113), 80.5% (91/113) and 19.5% (22/113), respectively. The dynamic changes curve showed that HIV-1 DNA load was relatively high (>800 copies /106 PBMCs) before ART, and droped rapidly (<400 copies /106 PBMCs) after ART for 1 year. However, HIV-1 DNA load decreased insignificantly from the second year of ART, and remained to be 269 copies/106 PBMCs after ART for 6 years. Univariable logistic regression analysis indicated that OR (95%CI) of CD8, CD4/CD8 and HIV-1 DNA load were 1.00 (1.00-1.00), 0.30 (0.09-1.05) and 1.01 (1.00-1.01), respectively. Multivariable logistic regression analysis showed that OR value of HIV-1 DNA load base was 1.00 (1.00-1.01). Conclusions: HIV-1 DNA load decreased significantly in the first year of ART, then remained stable for years. HIV-1 DNA load base was the key factor associated with the decrease of HIV-1 DNA load, the lower the HIV-1 DNA load base, the lower HIV-1 DNA load. Therefore, earlier ART can contribute to the decrease of HIV-1 DNA load.

[Application of anti-HCV and HCV RNA detection in intravenous drug users].

Objective: To explore the diagnostic value of anti-HCV and HCV RNA so as to provide an accurate and efficient detection strategy for the diagnosis of HCV in intravenous drug users. Methods: 527 plasma samples from intravenous drug users were collected, and preliminary anti-HCV ELISA screening test was performed. A recombinant immunoblot assay (RIBA) was used as confirmatory assay for reactive antibody samples. All samples were tested for HCV RNA, followed by analysis of anti-HCV screening test, RIBA and HCV nucleic acid test results. Results: Anti-HCV ELISA results were reactive in 386 out of 527 intravenous drug users and non-reactive in 141. Among the 386 reactive antibody samples detected by RIBA, 370 cases were anti-HCV positive, 6 cases were anti-HCV indeterminate and 10 cases were anti-HCV negative. Anti-HCV ELISA and RIBA positive coincidence detection rate was 95.85% (370/386), and 70.21% (370/527) among intravenous drug users. HCV RNA was negative in all 10 anti-HCV RIBA non-reactive samples. 376 anti-HCV RIBA-positive and indeterminate samples were tested for HCV RNA, of which 56.93% (300/527) were current HCV infection, and 14.42% (76/527) were past HCV infection. Among 141 anti-HCV ELISA negative samples, the residual risk by anti-HCV ELISA screening for HCV RNA was 1.52% (8/527). HCV viral load distribution among intravenous drug users showed that the high viral load value (>10(7) IU/ml) and low viral load values (< 10(2) IU/ml) accounted for 1.95% and 2.27%, respectively, while the samples with viral load value of 1×10(2) ~ 1×10(7) IU/ mL accounted for 95.78% (295/308), and were mainly distributed in 1×10(5) ~ 1×10(6) IU/ml (37.99%). ELISA + RIBA + NAT assay detection strategies had differentiated 300 cases of current HCV infection, 76 cases of past HCV infection and 10 cases of false positive anti-HCV results, while ELISA+NAT assay detection strategies had only detected 300 cases of current HCV infection. However, of the 386 positive subjects screened for antibodies, 10 (2.59%) were undifferentiated false positives. Conclusion: Intravenous drug users are the high-risk population of HCV infection with high prevalence and high viral load. Anti-HCV screening for intravenous drug users will have a certain degree of residual risk. Therefore, anti-HCV ELISA screening and nucleic acid detection strategy can accurately diagnose the current infected patients; however, it cannot distinguish the false positive results of antibody screening.

[Advances in studies of HCV nucleic acid testing for clinical diagnosis].

HCV infection is of global concern with the characteristic of insidious onset. Laboratory testing stands indispensably for clinical diagnosis with antibody assay and nucleic acid testing the main methods being adopted. For early detection and diagnosis of HCV infection, it is important to choose the best detection method and diagnostic strategy. This paper reviews the HCV nucleic acid testing methods, as well as performance evaluation of reagents and current strategies.

Effect of miR-126 on intracranial aneurysms and its predictive value for rupture of aneurysms.

OBJECTIVE: This study aimed to investigate the effect of miR-126 on intracranial aneurysm (IA) and its predictive value for aneurysm rupture. PATIENTS AND METHODS: Altogether 102 patients (patient group) with IA diagnosed in the Jinhua Municipal Central Hospital from July 2016 to April 2018, and 80 healthy people (normal group) who underwent physical examination during the same period were collected. QRT-PCR was used to detect the expression of miR-126 in serum, analyze the expression of miR-126 in IA, and explore the predictive value on IA rupture. Potential target genes of miR-126 were analyzed by target gene prediction website, and David was used to analyze the enrichment of miR-126 target gene GO and KEGG. RESULTS: The expression of miR-126 in serum of patient group was significantly higher than that of normal group (p < 0.05), ROC curve area was 0.966. The high expressions of miR-126 were directly related to the possibility of large lesions (p < 0.05). Multivariate analysis showed that lesion size and miR-126 expression were independent risk factors for rupture of IA patients. ROC curve showed that lesion size and miR-126 expression area under the curve were 0.707 and 0.827. Altogether 520 potential target sites were found by Venn diagram of Targetscan, miRDB, and Starbase online miR-126 prediction website. GO enrichment and KEGG analysis by David online software found that miR-126 target genes were mainly enriched in 169 biological processes, such as nucleus, transcription, DNA-templated, transcription factor activity, sequence-specific DNA binding, protein binding, and phosphatidylinositol phosphorylation. KEGG analysis found that miR-126 target genes were significantly enriched in MAPK signaling pathway, pathways in cancer, ErbB signaling pathway, MicroRNAs in cancer, and Thyroid hormone signaling pathway. CONCLUSIONS: MiR-126 can be used as a potential diagnostic and predictive indicator for IA occurrence and IA rupture.

[Progress in HIV-2 detection methodology].

Laboratory test is the routine method of diagnosis, monitoring and blood screening of HIV infection, and main basis for early diagnosis of AIDS. HIV is divided into HIV-1 and HIV-2 subtypes, HIV-1 infection is the major cause of AIDS pandemic, while HIV-2 infection occurs in limited areas in the world, mainly in West Africa. HIV-2 infection has been reported in China since 1998. They are sporadic cases, and mainly HIV-1/HIV-2 mixed infections. There are less concerns about HIV-2 detection in China at present, and domestic HIV-2 detection reagents have not come into the market. At present, the detection method of HIV-2 is mainly antibody test and nucleic acid test. The initial screening is through rapid test and other methods and the confirmation is depended on Western Blot and Line Immune Assay. According to the HIV antibody test results, HIV-2 infection is confirmed. With the rapid development of molecular biology, the diagnostic method of nucleic acid detection laboratory has made great progress.

Reduced-order modelling of parameter-dependent, linear and nonlinear dynamic partial differential equation models.

In this paper, we develop reduced-order models for dynamic, parameter-dependent, linear and nonlinear partial differential equations using proper orthogonal decomposition (POD). The main challenges are to accurately and efficiently approximate the POD bases for new parameter values and, in the case of nonlinear problems, to efficiently handle the nonlinear terms. We use a Bayesian nonlinear regression approach to learn the snapshots of the solutions and the nonlinearities for new parameter values. Computational efficiency is ensured by using manifold learning to perform the emulation in a low-dimensional space. The accuracy of the method is demonstrated on a linear and a nonlinear example, with comparisons with a global basis approach.

Relationship between TBX20 gene polymorphism and congenital heart disease.

Congenital heart disease in children is a type of birth defect. Previous studies have suggested that the transcription factor, TBX20, is involved in the occurrence and development of congenital heart disease in children; however, the specific regulatory mechanisms are yet to be evaluated. Hence, this study aimed to evaluate the relationship between the TBX20 polymorphism and the occurrence and development of congenital heart disease. The TBX20 gene sequence was obtained from the NCBI database and the polymorphic locus candidate was predicted. Thereafter, the specific gene primers were designed for the restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) of DNA extracted from the blood of 80 patients with congenital heart disease and 80 controls. The results of the PCR were subjected to correlation analysis to identify the differences between the amplicons and to determine the relationship between the TBX20 gene polymorphism and congenital heart disease. One of the single nucleotide polymorphic locus was found to be rs3999950: c.774T>C (Ala265Ala). The TC genotype frequency in the patients was higher than that in the controls, similar to that for the C locus. The odds ratio of the TC genotypes was above 1, indicating that the presence of the TC genotype increases the incidence of congenital heart diseases. Thus, rs3999950 may be associated with congenital heart disease, and TBX20 may predispose children to the defect.