DNA, Viral ; analysis ; Drug Resistance, Viral ; Hepatitis B ; drug therapy ; immunology ; virology ; Humans ; Viral Load

No abstract available.
Hepatitis B* ; Hepatitis* ; Humans ; Mothers* ; Tenofovir* ; Viral Load*

A large-scale pandemic by human influenza virus H1N1 in 2009 caused severe health, social, and economic impacts. In this study, a photocatalyst technology based on TiO2, was evaluated for inactivation of a human influenza virus H1N1 isolated from a patient. The virus titer was reduced by 103.16-fold within 24 h and more than 104.31-fold inactivation within 48 h and 72 h. These results suggest that the tested photocatalyst technology based on TiO2 can be used for reduction of influenza A virus adherence to other surfaces with Hizen-s inside diverse buildings, enabling effective control of its indirect contact infection. The photocatalyst is expected also to reduce level of the aerosol transmission of the virus.
Humans ; Influenza A virus ; Influenza, Human ; Pandemics ; Viral Load ; Viruses

Humans ; Child ; SARS-CoV-2 ; Viral Load ; COVID-19 ; Parents

The recent development of molecular diagnostic assays like as polymerase chain reaction (PCR) has provided powerful tools for the diagnosis of viral infection in the clinical fields. To ensure optimal therapeutic and prognostic value, it is important to establish whether viral load measurements are affected by repeated freeze-thaw (FT) cycles since the freezing of clinical samples is a universal method of specimen storage. This study was done to determine the effect of freezing and thawing of various samples on the quantitation and positivity of viral DNA. For this study, three different types of samples being used frequently in clinical fields were selected. Those samples contained ovine herpesvirus-2 (OvHV-2), a member of the gamma herpesviruses (genus Rhadinovirus). Two OvHV-2 DNA positive plasma samples, two peripheral blood mononuclear cell (PBMC) samples, and two nasal swab samples were randomly selected. They were carefully aliquated into 8 tubes for each sample. The aliquoted samples were frozen and thawed 0, 3, 6, 9, 12, 15, 18, and 21 times for each aliquot and then analyzed for changes on DNA levels and positivity. OvHV-2 DNA positivity and quantitation were tested by using nested PCR and real-time PCR, respectively. Twenty-one cycles of freezing and thawing did not significantly change this herpesviral DNA positivity in any of the samples tested. However, the decreases of viral DNA copies were observed in all samples by the increasing of FT cycles. In conclusion, the integrity of herpesviral DNAs in clinical specimens may be degraded by the increasing FT cycles. These results implicate that there is a need to aliquot specimen when it is first collected in order to reduce FT cycles during its analysis.
Diagnosis ; DNA* ; DNA, Viral ; Freezing ; Herpesviridae ; Pathology, Molecular ; Plasma ; Polymerase Chain Reaction ; Real-Time Polymerase Chain Reaction ; Viral Load

OBJECTIVETo evaluate the amplification rate and the lowestlower detection limit of an in-house HIV-1 Drug resistant (HIVDR) genotyping test.

METHODSA total of 30 plasma samples were selected, which covered all major HIV-1 subtypes predominating prevailing in China (B', CRF07_BC, CRF01 _AE). The viral loads of the 30 selected samples were detected in triplicate by Easy Q method and the average values were taken as the viral loads of the samples. Each sample was diluted to the concentration of > 1000 copies/ml, 401-1000 copies/ml, 101-400 copies/ml, 50-100 copies/ml and < 50 copies/ml with HIV-negative plasma. After extraction of nucleic acids, RT-PCR and nested PCR amplification were performed, the efficiency of amplification of each subtype and the minimum detection limit were determined statistically based on the PCR results.

RESULTSThe viral loads of the selected samples ranged from 2.03 x 10(2)-5.92 x 10(4) copies/ml. The sample of 50-1000 copies/ml have a high amplification rate (86%).

CONCLUSIONThe In-house method for HIV-1 drug resistance genotyping has a high sensitivity with a high successful amplification rate, especially in the samples with low viral load. This method can be used to the detection of drug-resistant virus and to provide scientific data to treatment options for patients.

China ; Drug Resistance, Viral ; Genotype ; HIV-1 ; classification ; drug effects ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Viral Load

OBJECTIVETo compare the results of detecting HIV-1 load by using NucliSens HIV-1 QT and Amplicor HIV-1 monitor 1.5 assays.

METHODSEighty-two clinical samples were collected and HIV viral load was determined with the above-mentioned two methods.

RESULTSThe number of samples in which values obtained by NucliSens HIV-1 QT and Amplicor HIV-1 monitor 1.5 differed by <0.5 log10 RNA copies/ml and in which the viral load was undetectable accounted for 88.9 percent of the measures. The correlation coefficient between the two methods was 0.956 in 56 samples of Deltalog10 VL<0.5.

CONCLUSIONThe results of HIV-1 viral load determination with the two methods are highly comparable.

HIV Infections ; virology ; HIV-1 ; genetics ; isolation & purification ; Humans ; Nucleic Acid Amplification Techniques ; instrumentation ; methods ; RNA, Viral ; genetics ; Viral Load

OBJECTIVETo investigate the drug resistance of HIV patients to the HIV-1 CRF01_AE and CRF07_BC strains in Sichuan province during 2010 to 2013.

METHODS1.5 ml of plasma were collected from AIDS patients who had been receiving anti-retroviral treatment for over 6 months but still had a HIV-1 virus load of over 1 000 copies/ml from January 1, 2010 to December 31, 2013 in Sichuan province. Genetic analysis of the HIV-1 pol gene was performed using self-established method, and patients with a positive drug-resistant HIV-1 pol gene mutation were included. HIV-1 poly gene was successfully sequenced for a total of 1 213 patients. Drug resistance of different HIV-1 strains was compared with χ2 test or Fisher exact test.

RESULTS558 cases (46.0%) of the 1 213 successfully sequenced patients were infected by HIV-1-strains with drug-resistant mutations, including 327 cases (58.6%) infected by CRF01_AE strain, 126 (22.6%) by CRF07_BC strain, 46 (8.2%) by CRF08_BC strain, 33 (5.9%) by B strain, 4 (0.7%) by C strain, 1 (0.2%) by CRF02_AG strain, and 21 (3.8%) by unidentified strains. Drug-resistant mutation analysis revealed that L33, F116, L74, Q151, and T69 resistance mutations occurred only in the CRF01_AE strain, while A71, K43, and Q58 resistance mutations occurred only in the CRF07_BC strain; in nuclear nucleoside reverse transcriptase inhibitors (NRTIs) and non nucleoside reverse transcriptase inhibitors (NNRTIs), CRF01_AE subtype strains showed highly resistant rate were higher than CRF07_BC, CRF08_BC and B subtype strains, with the differences were statistically significant (P<0.05).

CONCLUSIONThe drug-resistant HIV-1 strains in Sichuan mainly included the CRF01_AE and CRF07_BC strains, which had different resistance mutations.

Base Sequence ; Drug Resistance, Viral ; Genes, pol ; HIV Infections ; HIV-1 ; Humans ; Mutation ; Reverse Transcriptase Inhibitors ; Viral Load

BACKGROUNDMan who has sex with man (MSM) is one of the high risk groups for spreading HIV/AIDS. It was reported that the most prevalent human immunodeficiency virus type 1 (HIV-1) strain among MSM is subtype B; however, T cell immunity remains unknown across the HIV-1 B genome in this population.

METHODSUsing Elispot assay with synthetic peptides spanning the sequence of HIV-1 consensus B, HIV-1-specific cytotoxic T-cell lymphocyte responses were quantified among 3 treated and 19 untreated HIV-1 infected MSM from Beijing, China. Cross-sectional association between viral loads and cellular immune responses were analyzed.

RESULTSPeptide pools corresponding to each HIV-1 protein were used for Env, Gag, Pol, Nef, Tat/Rev, Vpr/Vpu and Vif. The results showed that the magnitude of T cell responses in the 3 treated HIV(+) MSM group [median, 770 spot forming cells (SFCs) per 10(6) peripheral blood mononuclear cells (PBMCs)] might be significantly lower than that in the 19 untreated HIV(+) MSM group (median, 6175 SFCs per 10(6) PBMCs). Nef, Gag and Pol are the most frequently targeted HIV-1 antigens; and 16 subjects (73%) were identified with vigorous T cell immunity against each of these three proteins. The overall magnitude of T cell immunity closely related to its breadth (r = 0.72, P < 0.05) and was inversely but weakly associated with viral loads (r = -0.15). Further analysis showed that both Gag (r = -0.24) and Pol specific T cells (r = -0.12) contributed to this inverse association whereas Nef specific T cells showed no association with viral loads.

CONCLUSIONSThe magnitude of HIV-1 specific T cells is inversely but weakly associated with viral loads among MSM; HIV-specific T cell responses against conservative sequences (Gag and Pol) are the main contributors to this association among Chinese HIV(+) MSM. These findings have important implications for vaccine design.

Adult ; China ; Genome, Viral ; immunology ; HIV-1 ; immunology ; Homosexuality ; Humans ; Male ; T-Lymphocytes, Cytotoxic ; immunology ; Viral Load

OBJECTIVETo establish the single genome amplification (SGA) method and analyze the quasispecies in HIV-infected patients.

METHODSAll 6 sample RNA acquired in 2010 in Shenzhen and genetic sequenced as overlap peaks were extracted and diluted to a single copy, nest-PCR after one step RT-PCR was employed to amplify HIV-1 genome, and then PCR products was purified and sequenced. Mega 4.02 software was used to analyze the genetic distance among HIV-1 quasispecies, and phylogenetic tree was constructed.

RESULTSOur data showed that viral sequences derived from different patients were grouped into different clusters. Subcluster was also observed in several clusters, indicating these existed competition and preferential replication of certain viral strains. The genetic distance within one cluster of 6 samples were between 0.008 and 0.06, it was likely to associate with the duration since infection and viral load.

CONCLUSIONSGA is a useful approach to gain information on quasispecies, the genetic distance within one cluster may help to determine the infection time and immune escaping. The analysis of related affecting factors need more samples.

Base Sequence ; Genome, Viral ; HIV Infections ; HIV-1 ; Humans ; Phylogeny ; Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; Viral Load