Displaying publications 61 - 80 of 137 in total

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  1. Tiong V, Hassandarvish P, Bakar SA, Mohamed NA, Wan Sulaiman WS, Baharom N, et al.
    Sci Rep, 2021 10 15;11(1):20502.
    PMID: 34654867 DOI: 10.1038/s41598-021-99866-w
    The COVID-19 is difficult to contain due to its high transmissibility rate and a long incubation period of 5 to 14 days. Moreover, more than half of the infected patients were young and asymptomatic. Virus transmission through asymptomatic patients is a major challenge to disease containment. Due to limited treatment options, preventive measures play major role in controlling the disease spread. Gargling with antiseptic formulation may have potential role in eliminating the virus in the throat. Four commercially available mouthwash/gargle formulations were tested for virucidal activity against SARS-CoV-2 in both clean (0.3 g/l BSA) and dirty (0.3 g/l BSA + 3 mL/L human erythrocytes) conditions at time points 30 and 60 s. The virus was isolated and propagated in Vero E6 cells. The cytotoxicity of the products to the Vero E6 was evaluated by kill time assay based on the European Standard EN14476:2013/FprA1:2015 protocol. Virus titres were calculated as 50% tissue culture infectious dose (TCID50/mL) using the Spearman-Karber method. A reduction in virus titer of 4 log10 corresponds to an inactivation of ≥ 99.99%. Formulations with cetylperidinium chloride, chlorhexidine and hexitidine achieved > 4 log10 reduction in viral titres when exposed within 30 s under both clean and dirty conditions. Thymol formulations achieved only 0.5 log10 reduction in viral titres. In addition, salt water was not proven effective. Gargle formulations with cetylperidinium chloride, chlorhexidine and hexetidine have great potential in reducing SAR-CoV-2 at the source of entry into the body, thus minimizing risk of transmission of COVID-19.
    Matched MeSH terms: Viral Load
  2. Lee JH, Hammoud DA, Cong Y, Huzella LM, Castro MA, Solomon J, et al.
    J Infect Dis, 2020 05 11;221(Suppl 4):S419-S430.
    PMID: 31687756 DOI: 10.1093/infdis/jiz502
    Nipah virus (NiV) is an emerging virus associated with outbreaks of acute respiratory disease and encephalitis. To develop a neurological model for NiV infection, we exposed 6 adult African green monkeys to a large-particle (approximately 12 μm) aerosol containing NiV (Malaysian isolate). Brain magnetic resonance images were obtained at baseline, every 3 days after exposure for 2 weeks, and then weekly until week 8 after exposure. Four of six animals showed abnormalities reminiscent of human disease in brain magnetic resonance images. Abnormalities ranged from cytotoxic edema to vasogenic edema. The majority of lesions were small infarcts, and a few showed inflammatory or encephalitic changes. Resolution or decreased size in some lesions resembled findings reported in patients with NiV infection. Histological lesions in the brain included multifocal areas of encephalomalacia, corresponding to known ischemic foci. In other regions of the brain there was evidence of vasculitis, with perivascular infiltrates of inflammatory cells and rare intravascular fibrin thrombi. This animal model will help us better understand the acute neurological features of NiV infection and develop therapeutic approaches for managing disease caused by NiV infection.
    Matched MeSH terms: Viral Load
  3. Prasad AN, Woolsey C, Geisbert JB, Agans KN, Borisevich V, Deer DJ, et al.
    J Infect Dis, 2020 05 11;221(Suppl 4):S436-S447.
    PMID: 32022850 DOI: 10.1093/infdis/jiz613
    BACKGROUND: The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are capable of causing severe and often lethal respiratory and/or neurologic disease in animals and humans. Given the sporadic nature of henipavirus outbreaks, licensure of vaccines and therapeutics for human use will likely require demonstration of efficacy in animal models that faithfully reproduce the human condition. Currently, the African green monkey (AGM) best mimics human henipavirus-induced disease.

    METHODS: The pathogenic potential of HeV and both strains of NiV (Malaysia, Bangladesh) was assessed in cynomolgus monkeys and compared with henipavirus-infected historical control AGMs. Multiplex gene and protein expression assays were used to compare host responses.

    RESULTS: In contrast to AGMs, in which henipaviruses cause severe and usually lethal disease, HeV and NiVs caused only mild or asymptomatic infections in macaques. All henipaviruses replicated in macaques with similar kinetics as in AGMs. Infection in macaques was associated with activation and predicted recruitment of cytotoxic CD8+ T cells, Th1 cells, IgM+ B cells, and plasma cells. Conversely, fatal outcome in AGMs was associated with aberrant innate immune signaling, complement dysregulation, Th2 skewing, and increased secretion of MCP-1.

    CONCLUSION: The restriction factors identified in macaques can be harnessed for development of effective countermeasures against henipavirus disease.

    Matched MeSH terms: Viral Load
  4. Raihan R, Tabassum S, Al-Mahtab M, Nessa A, Jahan M, Shamim Kabir CM, et al.
    Euroasian J Hepatogastroenterol, 2015 Jan-Jun;5(1):7-10.
    PMID: 29201677 DOI: 10.5005/jp-journals-10018-1120
    Background: Hepatitis B virus (HBV) infection has many faces. Precore and core promoter mutants resemble inactive carrier status. The identification of hepatitis B core antigen (HBcAg) in hepatocytes may have variable clinical significance. The present study was undertaken to detect HBcAg in chronic hepatitis B (CHB) patients and to assess the efficacy of detection system by indirect immunofluorescence (IIF) and indirect immunoperoxidase (IIP).

    Materials and methods: The study was done in 70 chronic HBV-infected patients. Out of 70 patients, eight (11.4%) were hepatitis B e antigen (HBeAg) positive and 62 (88.57%) were HBeAg negative. Hepatitis B core antigen was detected by indirect immunofluorescence (IIF) and indirect immunoperoxidase (IIP) methods in liver tissue.

    Results: All HBeAg positive patients expressed HBcAg by both IIF and IIP methods. Out of 62 patients with HBeAg-negative CHB, HBcAg was detected by IIF in 55 (88.7%) patients and by IIP in 51 (82.26%) patients. A positive relation among viral load and HBcAg detection was also found. This was more evident in the case of HBeAg negative patients and showed a positive relation with HBV DNA levels.

    Conclusion: Hepatitis B core antigen can be detected using the IIF from formalin fixed paraffin block preparation and also by IIP method. This seems to reflect the magnitudes of HBV replication in CHB.

    How to cite this article: Raihan R, Tabassum S, Al-Mahtab M, Nessa A, Jahan M, Kabir CMS, Kamal M, Aguilar JC. Hepatitis B Core Antigen in Hepatocytes of Chronic Hepatitis B: Comparison between Indirect Immunofluorescence and Immunoperoxidase Method. Euroasian J Hepato-Gastroenterol 2015;5(1):7-10.
    Matched MeSH terms: Viral Load
  5. Zain RM, Ibrahim N, Ismail S, Suppiah J, Mat Rahim NA, Thayan R
    Asian Pac J Trop Med, 2017 Jan;10(1):75-78.
    PMID: 28107870 DOI: 10.1016/j.apjtm.2016.12.005
    OBJECTIVE: To determine drug resistance mutations and the HIV-1 subtypes among antiretroviral treatment naive HIV-1 patients in Peninsular Malaysia.

    METHODS: A total of 45 samples from four hospitals that provide HIV viral load services were subjected to the amplification of the protease and two third of reverse transcriptase regions of the pol gene by RT-PCR and Sanger sequencing. Drug resistance mutation (DRM) interpretation reports the presence of mutations related to protease inhibitors (PIs), Nucleoside reverse-transcriptase inhibitors (NRTI) and Non-nucleoside reverse-transcriptase inhibitors (NNRTI) based on analysis using Stanford HIV database program.

    RESULTS: DRMs were identified in 35% of patients, among which 46.7% of them showed minor resistance to protease inhibitor with A71V and L10l were the commonest DRMs detected. About 21.4% and 50.0% of patients had mutations to NRTIs and NNRTIs, respectively. CRF01_AE was found to be the predominant HIV-1 subtype.

    CONCLUSIONS: These findings have served as an initial crucial data in determining the prevalence of transmitted HIV-1 drug resistance for the country. However, more samples from various parts of the country need to be accumulated and analyzed to provide overall HIV-1 drug resistance in the country.

    Matched MeSH terms: Viral Load
  6. Fahrni ML, Misran NFL, Abidin ZZ, Chidambaram SK, Lazzarino AI
    J Infect Public Health, 2023 Jan;16(1):96-103.
    PMID: 36508946 DOI: 10.1016/j.jiph.2022.12.001
    BACKGROUND: While efavirenz-associated adverse drug events (ADEs) were widely established, the clinical relevance is uncertain.

    OBJECTIVES: We aimed to assess the extent of treatment interruption caused by efavirenz-associated ADEs.

    METHODS: A case-control study of efavirenz recipients who did, versus did not (control) develop adverse drug events (ADE), and who were matched for baseline CD4 + at a ratio of 1:1.3 was conducted. Antiretroviral -naïve patients who were started on efavirenz were followed up retrospectively, and their records scrutinized every month for 2 years. Demographic and clinical predictors of treatment interruption were computed using Cox proportional hazard models. Kaplan- Meier curves were plotted to assess time to treatment interruption for the two groups. Clinical endpoints were: i) efficacy -improved CD4 + counts and/or viral load (VL) suppression, ii) safety -absence of treatment-limiting toxicities, and iii) durability - no interruption until follow-up ended.

    RESULTS: Both groups had comparable CD4 + counts at baseline (p = 0.15). At t = 24-months, VL in both groups were suppressed to undetectable levels (<20 copies/mL) while median CD4 + was 353 cells/µL (IQR: 249-460). The mean time on treatment was 23 months (95% CI, 22.3 -23.4) in the control group without ADE and 20 months (95% CI, 18.9 - 21.6) in the ADE group (p = 0.001). Kaplan-Meier plots demonstrated that 59.5% of patients who experienced ≥ 1 ADE versus 81% of those who did not experience any ADE were estimated to continue treatment for up to 24 months with no interruption (p = 0.001). Most interruptions to EFV treatment occurred in the presence of opportunistic infections and these were detected within the first 5 months of treatment initiation. Independent predictors which negatively impacted the dependent variable i.e., treatment durability, were intravenous drug use (adjusted hazard ratio, aHR 2.17, 95% CI, 1.03-4.61, p = 0.043), presence of ≥ 1 opportunistic infection(s) (aHR 2.2, 95% CI, 1.13-4.21, p = 0.021), and presence of ≥ 1 serious ADE(s) (aHR 4.18, 95% CI, 1.98-8.85, p = 0.00).

    CONCLUSION: Efavirenz' role as the preferred first-line regimen for South-East Asia's resource-limited regions will need to be carefully tailored to suit the regional population. Findings have implications to policy-makers and clinicians, particularly for the treatment of patients who develop ADEs and opportunistic infections, and for intravenous drug user subgroups.

    Matched MeSH terms: Viral Load
  7. Barré-Sinoussi F, Abdool Karim SS, Albert J, Bekker LG, Beyrer C, Cahn P, et al.
    J Int AIDS Soc, 2018 Jul;21(7):e25161.
    PMID: 30044059 DOI: 10.1002/jia2.25161
    INTRODUCTION: Globally, prosecutions for non-disclosure, exposure or transmission of HIV frequently relate to sexual activity, biting, or spitting. This includes instances in which no harm was intended, HIV transmission did not occur, and HIV transmission was extremely unlikely or not possible. This suggests prosecutions are not always guided by the best available scientific and medical evidence.

    DISCUSSION: Twenty scientists from regions across the world developed this Expert Consensus Statement to address the use of HIV science by the criminal justice system. A detailed analysis of the best available scientific and medical research data on HIV transmission, treatment effectiveness and forensic phylogenetic evidence was performed and described so it may be better understood in criminal law contexts. Description of the possibility of HIV transmission was limited to acts most often at issue in criminal cases. The possibility of HIV transmission during a single, specific act was positioned along a continuum of risk, noting that the possibility of HIV transmission varies according to a range of intersecting factors including viral load, condom use, and other risk reduction practices. Current evidence suggests the possibility of HIV transmission during a single episode of sex, biting or spitting ranges from no possibility to low possibility. Further research considered the positive health impact of modern antiretroviral therapies that have improved the life expectancy of most people living with HIV to a point similar to their HIV-negative counterparts, transforming HIV infection into a chronic, manageable health condition. Lastly, consideration of the use of scientific evidence in court found that phylogenetic analysis alone cannot prove beyond reasonable doubt that one person infected another although it can be used to exonerate a defendant.

    CONCLUSIONS: The application of up-to-date scientific evidence in criminal cases has the potential to limit unjust prosecutions and convictions. The authors recommend that caution be exercised when considering prosecution, and encourage governments and those working in legal and judicial systems to pay close attention to the significant advances in HIV science that have occurred over the last three decades to ensure current scientific knowledge informs application of the law in cases related to HIV.

    Matched MeSH terms: Viral Load
  8. del Amo J, Moreno S, Bucher HC, Furrer H, Logan R, Sterne J, et al.
    Clin Infect Dis, 2012 May;54(9):1364-72.
    PMID: 22460971 DOI: 10.1093/cid/cis203
    BACKGROUND: The lower tuberculosis incidence reported in human immunodeficiency virus (HIV)-positive individuals receiving combined antiretroviral therapy (cART) is difficult to interpret causally. Furthermore, the role of unmasking immune reconstitution inflammatory syndrome (IRIS) is unclear. We aim to estimate the effect of cART on tuberculosis incidence in HIV-positive individuals in high-income countries.

    METHODS: The HIV-CAUSAL Collaboration consisted of 12 cohorts from the United States and Europe of HIV-positive, ART-naive, AIDS-free individuals aged ≥18 years with baseline CD4 cell count and HIV RNA levels followed up from 1996 through 2007. We estimated hazard ratios (HRs) for cART versus no cART, adjusted for time-varying CD4 cell count and HIV RNA level via inverse probability weighting.

    RESULTS: Of 65 121 individuals, 712 developed tuberculosis over 28 months of median follow-up (incidence, 3.0 cases per 1000 person-years). The HR for tuberculosis for cART versus no cART was 0.56 (95% confidence interval [CI], 0.44-0.72) overall, 1.04 (95% CI, 0.64-1.68) for individuals aged >50 years, and 1.46 (95% CI, 0.70-3.04) for people with a CD4 cell count of <50 cells/μL. Compared with people who had not started cART, HRs differed by time since cART initiation: 1.36 (95% CI, 0.98-1.89) for initiation <3 months ago and 0.44 (95% CI, 0.34-0.58) for initiation ≥3 months ago. Compared with people who had not initiated cART, HRs <3 months after cART initiation were 0.67 (95% CI, 0.38-1.18), 1.51 (95% CI, 0.98-2.31), and 3.20 (95% CI, 1.34-7.60) for people <35, 35-50, and >50 years old, respectively, and 2.30 (95% CI, 1.03-5.14) for people with a CD4 cell count of <50 cells/μL.

    CONCLUSIONS: Tuberculosis incidence decreased after cART initiation but not among people >50 years old or with CD4 cell counts of <50 cells/μL. Despite an overall decrease in tuberculosis incidence, the increased rate during 3 months of ART suggests unmasking IRIS.

    Matched MeSH terms: Viral Load/drug effects
  9. Kok YY, Chu WL, Phang SM, Mohamed SM, Naidu R, Lai PJ, et al.
    J Zhejiang Univ Sci B, 2011 May;12(5):335-45.
    PMID: 21528487 DOI: 10.1631/jzus.B1000336
    This study aimed to assess the inhibitory activities of methanol extracts from the microalgae Ankistrodesmus convolutus, Synechococcus elongatus, and Spirulina platensis against Epstein-Barr virus (EBV) in three Burkitt's lymphoma (BL) cell lines, namely Akata, B95-8, and P3HR-1. The antiviral activity was assessed by quantifying the cell-free EBV DNA using real-time polymerase chain reaction (PCR) technique. The methanol extracts from Ankistrodesmus convolutus and Synechococcus elongatus displayed low cytotoxicity and potent effect in reducing cell-free EBV DNA (EC(50)<0.01 µg/ml) with a high therapeutic index (>28000). After fractionation by column chromatography, the fraction from Synechococcus elongatus (SEF1) reduced the cell-free EBV DNA most effectively (EC(50)=2.9 µg/ml, therapeutic index>69). Upon further fractionation by high performance liquid chromatography (HPLC), the sub-fraction SEF1'a was most active in reducing the cell-free EBV DNA (EC(50)=1.38 µg/ml, therapeutic index>14.5). This study suggests that microalgae could be a potential source of antiviral compounds that can be used against EBV.
    Matched MeSH terms: Viral Load/drug effects
  10. Hejazi N, Rajikan R, Choong CL, Sahar S
    BMC Public Health, 2013;13:758.
    PMID: 23947428 DOI: 10.1186/1471-2458-13-758
    In the current two decades, dyslipidemia and increased blood glucose as metabolic abnormalities are the most common health threats with a high incidence among HIV/AIDS patients on antiretroviral (ARV) treatment. Scientific investigations and reports on lipid and glucose disorders among HIV infected communities are inadequate especially in those developing such as Malaysia. This cross-sectional survey was mainly aimed to evaluate the prevalence of metabolic abnormalities and associated risk factors among HIV infected population patients on ARV medication.
    Matched MeSH terms: Viral Load
  11. Chiam CW, Chan YF, Loong SK, Yong SS, Hooi PS, Sam IC
    Diagn Microbiol Infect Dis, 2013 Oct;77(2):133-7.
    PMID: 23886793 DOI: 10.1016/j.diagmicrobio.2013.06.018
    Quantitative real-time polymerase chain reaction (qRT-PCR) is useful for diagnosis and studying virus replication. We developed positive- and negative-strand qRT-PCR assays to detect nsP3 of chikungunya virus (CHIKV), a positive-strand RNA alphavirus that causes epidemic fever, rash, and arthritis. The positive- and negative-strand qRT-PCR assays had limits of quantification of 1 and 3 log10 RNA copies/reaction, respectively. Compared to a published E1 diagnostic assay using 30 laboratory-confirmed clinical samples, the positive-strand nsP3 qRT-PCR assay had higher R(2) and efficiency and detected more positive samples. Peak viral load of 12.9 log(10) RNA copies/mL was reached on day 2 of illness, and RNA was detectable up to day 9, even in the presence of anti-CHIKV IgM. There was no correlation between viral load and persistent arthralgia. The positive-strand nsP3 assay is suitable for diagnosis, while the negative-strand nsP3 assay, which uses tagged primers to increase specificity, is useful for study of active viral replication kinetics.
    Matched MeSH terms: Viral Load
  12. Alhoot MA, Wang SM, Sekaran SD
    PLoS Negl Trop Dis, 2011 Nov;5(11):e1410.
    PMID: 22140591 DOI: 10.1371/journal.pntd.0001410
    Dengue infection ranks as one of the most significant viral diseases of the globe. Currently, there is no specific vaccine or antiviral therapy for prevention or treatment. Monocytes/macrophages are the principal target cells for dengue virus and are responsible for disseminating the virus after its transmission. Dengue virus enters target cells via receptor-mediated endocytosis after the viral envelope protein E attaches to the cell surface receptor. This study aimed to investigate the effect of silencing the CD-14 associated molecule and clathrin-mediated endocytosis using siRNA on dengue virus entry into monocytes.
    Matched MeSH terms: Viral Load
  13. HIV-CAUSAL Collaboration, Ray M, Logan R, Sterne JA, Hernández-Díaz S, Robins JM, et al.
    AIDS, 2010 Jan 02;24(1):123-37.
    PMID: 19770621 DOI: 10.1097/QAD.0b013e3283324283
    OBJECTIVE: To estimate the effect of combined antiretroviral therapy (cART) on mortality among HIV-infected individuals after appropriate adjustment for time-varying confounding by indication.

    DESIGN: A collaboration of 12 prospective cohort studies from Europe and the United States (the HIV-CAUSAL Collaboration) that includes 62 760 HIV-infected, therapy-naive individuals followed for an average of 3.3 years. Inverse probability weighting of marginal structural models was used to adjust for measured confounding by indication.

    RESULTS: Two thousand and thirty-nine individuals died during the follow-up. The mortality hazard ratio was 0.48 (95% confidence interval 0.41-0.57) for cART initiation versus no initiation. In analyses stratified by CD4 cell count at baseline, the corresponding hazard ratios were 0.29 (0.22-0.37) for less than 100 cells/microl, 0.33 (0.25-0.44) for 100 to less than 200 cells/microl, 0.38 (0.28-0.52) for 200 to less than 350 cells/microl, 0.55 (0.41-0.74) for 350 to less than 500 cells/microl, and 0.77 (0.58-1.01) for 500 cells/microl or more. The estimated hazard ratio varied with years since initiation of cART from 0.57 (0.49-0.67) for less than 1 year since initiation to 0.21 (0.14-0.31) for 5 years or more (P value for trend <0.001).

    CONCLUSION: We estimated that cART halved the average mortality rate in HIV-infected individuals. The mortality reduction was greater in those with worse prognosis at the start of follow-up.

    Matched MeSH terms: Viral Load
  14. Yee PTI, Mohamed RAH, Ong SK, Tan KO, Poh CL
    Virus Res, 2017 06 15;238:243-252.
    PMID: 28705680 DOI: 10.1016/j.virusres.2017.07.010
    One of the leading causes of the hand, foot and mouth disease (HFMD) is Enterovirus 71 (EV-A71), displaying symptoms such as fever and ulcers in children but some strains can produce cardiopulmonary oedema which leads to death. There is no FDA-approved vaccine for prevention of severe HFMD. The molecular determinants of virulence for EV-A71 are unclear. It could be a single or a combination of amino acids that determines virulence in different EV-A71 genotype/sub-genotypes. Several EV-A71 strains bearing single nucleotide (nt) mutations were constructed and the contribution of each mutation to virulence was evaluated. The nt(s) that contributed to significant reduction in virulence in vitro were selected and each mutation was introduced separately into the genome to construct the multiply mutated EV-A71 strain (MMS) which carried six substitutions of nt(s) at the 5'-NTR (U700C), VP1-145 (E to G), VP1-98E, VP1-244K and G64R in the vaccine seed strain that had a partial deletion within the 5'-NTR region (nt. 475-485) of Δ11bp. In comparison to the wild type strain, the MMS showed low virulence as it produced very low RNA copy number, plaque count, VP1 and had 105-fold higher TCID50, indicative of a promising LAV candidate that should be further evaluated in vivo.
    Matched MeSH terms: Viral Load
  15. Yong YK, Saeidi A, Tan HY, Rosmawati M, Enström PF, Batran RA, et al.
    Front Immunol, 2018;9:472.
    PMID: 29616020 DOI: 10.3389/fimmu.2018.00472
    Mucosal-associated invariant T (MAIT) cells, defined as CD161++TCR iVα7.2+ T cells, play an important role in the innate defense against bacterial infections, and their functionality is impaired in chronic viral infections. Here, we investigated the frequency and functional role of MAIT cells in chronic hepatitis B virus (HBV) infection. The peripheral CD3+CD161++TCR iVα7.2+ MAIT cells in chronic HBV-infected patients and healthy controls were phenotypically characterized based on CD57, PD-1, TIM-3, and CTLA-4, as well as HLA-DR and CD38 expression. The frequency of MAIT cells was significantly decreased among chronic HBV-infected individuals as compared to controls. Expression of CD57, PD-1, CTLA-4, as well as HLA-DR and CD38 on MAIT cells was significantly elevated in chronic HBV-infected individuals relative to controls. The percentage of T cell receptor (TCR) iVα7.2+ CD161+ MAIT cells did not correlate with HBV viral load but inversely with HLA-DR on CD4+ T cells and MAIT cells and with CD57 on CD8+ T cells suggesting that decrease of MAIT cells may not be attributed to direct infection by HBV but driven by HBV-induced chronic immune activation. The percentage and expression levels of PD-1 as well as CTLA-4 on MAIT cells inversely correlated with plasma HBV-DNA levels, which may suggest either a role for MAIT cells in the control of HBV infection or the effect of HBV replication in the liver on MAIT cell phenotype. We report that decrease of TCR iVα7.2+ MAIT cells in the peripheral blood and their functions were seemingly impaired in chronic HBV-infected patients likely because of the increased expression of PD-1.
    Matched MeSH terms: Viral Load
  16. Yun SI, Song BH, Frank JC, Julander JG, Olsen AL, Polejaeva IA, et al.
    Viruses, 2018 08 11;10(8).
    PMID: 30103523 DOI: 10.3390/v10080422
    Zika virus (ZIKV) causes no-to-mild symptoms or severe neurological disorders. To investigate the importance of viral and host genetic variations in determining ZIKV infection outcomes, we created three full-length infectious cDNA clones as bacterial artificial chromosomes for each of three spatiotemporally distinct and genetically divergent ZIKVs: MR-766 (Uganda, 1947), P6-740 (Malaysia, 1966), and PRVABC-59 (Puerto Rico, 2015). Using the three molecularly cloned ZIKVs, together with 13 ZIKV region-specific polyclonal antibodies covering nearly the entire viral protein-coding region, we made three conceptual advances: (i) We created a comprehensive genome-wide portrait of ZIKV gene products and their related species, with several previously undescribed gene products identified in the case of all three molecularly cloned ZIKVs. (ii) We found that ZIKV has a broad cell tropism in vitro, being capable of establishing productive infection in 16 of 17 animal cell lines from 12 different species, although its growth kinetics varied depending on both the specific virus strain and host cell line. More importantly, we identified one ZIKV-non-susceptible bovine cell line that has a block in viral entry but fully supports the subsequent post-entry steps. (iii) We showed that in mice, the three molecularly cloned ZIKVs differ in their neuropathogenicity, depending on the particular combination of viral and host genetic backgrounds, as well as in the presence or absence of type I/II interferon signaling. Overall, our findings demonstrate the impact of viral and host genetic variations on the replication kinetics and neuropathogenicity of ZIKV and provide multiple avenues for developing and testing medical countermeasures against ZIKV.
    Matched MeSH terms: Viral Load
  17. Okamura T, Tsujimura Y, Soma S, Takahashi I, Matsuo K, Yasutomi Y
    J Gen Virol, 2016 Dec;97(12):3413-3426.
    PMID: 27902330 DOI: 10.1099/jgv.0.000641
    Simian immunodeficiency virus (SIV) infection models in cynomolgus macaques are important for analysis of the pathogenesis of immunodeficiency virus and for studies on the efficacy of new vaccine candidates. However, very little is known about the pathogenesis of SIV or simian human immunodeficiency virus (SHIV) in cynomolgus macaques from different Asian countries. In the present study, we analysed the infectivity and pathogenicity of CCR5-tropic SIVmac and those of dual-tropic SHIV89.6P inoculated into cynomolgus macaques in Indonesian, Malaysian or Philippine origin. The plasma viral loads in macaques infected with either SIVmac239 or SHIV89.6P were maintained at high levels. CD4+ T cell levels in macaques infected with SIVmac239 gradually decreased. All of the macaques infected with SHIV89.6P showed greatly reduced CD4+ T-cell numbers within 6 weeks of infection. Eight of the 11 macaques infected with SIVmac239 were killed due to AIDS symptoms after 2-4.5 years, while four of the five macaques infected with SHIV89.6P were killed due to AIDS symptoms after 1-3.5 years. We also analysed cynomolgus macaques infected intrarectally with repeated low, medium or high doses of SIVmac239, SIVmac251 or SHIV89.6P. Infection was confirmed by quantitative RT-PCR at more than 5000, 300 and 500 TCID50 for SIVmac239, SIVmac251 and SHIV89.6P, respectively. The present study indicates that cynomolgus macaques of Asian origin are highly susceptible to SIVmac and SHIV infection by both intravenous and mucosal routes. These models will be useful for studies on virus pathogenesis, vaccination and therapeutics against human immunodeficiency virus/AIDS.
    Matched MeSH terms: Viral Load
  18. Ross JL, Teeraananchai S, Lumbiganon P, Hansudewechakul R, Chokephaibulkit K, Khanh TH, et al.
    J Acquir Immune Defic Syndr, 2019 06 01;81(2):e28-e38.
    PMID: 30865173 DOI: 10.1097/QAI.0000000000002008
    BACKGROUND: Adolescents living with HIV (ALHIV) have poorer adherence and clinical outcomes than adults. We conducted a study to assess behavioral risks and antiretroviral therapy outcomes among ALHIV in Asia.

    METHODS: A prospective cohort study among ALHIV and matched HIV-uninfected controls aged 12-18 years was conducted at 9 sites in Malaysia, Thailand, and Vietnam from July 2013 to March 2017. Participants completed an audio computer-assisted self-interview at weeks 0, 48, 96, and 144. Virologic failure (VF) was defined as ≥1 viral load (VL) measurement >1000 copies/mL. Generalized estimating equations were used to identify predictors for VF.

    RESULTS: Of 250 ALHIV and 59 HIV-uninfected controls, 58% were Thai and 51% females. The median age was 14 years at enrollment; 93% of ALHIV were perinatally infected. At week 144, 66% of ALHIV were orphans vs. 28% of controls (P < 0.01); similar proportions of ALHIV and controls drank alcohol (58% vs. 65%), used inhalants (1% vs. 2%), had been sexually active (31% vs. 21%), and consistently used condoms (42% vs. 44%). Of the 73% of ALHIV with week 144 VL testing, median log VL was 1.60 (interquartile range 1.30-1.70) and 19% had VF. Over 70% of ALHIV had not disclosed their HIV status. Self-reported adherence ≥95% was 60% at week 144. Smoking cigarettes, >1 sexual partner, and living with nonparent relatives, a partner or alone, were associated with VF at any time.

    CONCLUSIONS: The subset of ALHIV with poorer adherence and VF require comprehensive interventions that address sexual risk, substance use, and HIV-status disclosure.

    Matched MeSH terms: Viral Load
  19. Loeliger KB, Altice FL, Desai MM, Ciarleglio MM, Gallagher C, Meyer JP
    Lancet HIV, 2018 02;5(2):e96-e106.
    PMID: 29191440 DOI: 10.1016/S2352-3018(17)30209-6
    BACKGROUND: Incarceration provides an opportunity for engagement in HIV care but is associated with poor HIV treatment outcomes after release. We aimed to assess post-release linkage to HIV care (LTC) and the effect of transitional case management services.

    METHODS: To create a retrospective cohort of all adults with HIV released from jails and prisons in Connecticut, USA (2007-14), we linked administrative custody and pharmacy databases with mandatory HIV/AIDS surveillance monitoring and case management data. We examined time to LTC (defined as first viral load measurement after release) and viral suppression at LTC. We used generalised estimating equations to show predictors of LTC within 14 days and 30 days of release.

    FINDINGS: Among 3302 incarceration periods for 1350 individuals between 2007 and 2014, 672 (21%) of 3181 periods had LTC within 14 days of release, 1042 (34%) of 3064 had LTC within 30 days of release, and 301 (29%) of 1042 had detectable viral loads at LTC. Factors positively associated with LTC within 14 days of release are intermediate (31-364 days) incarceration duration (adjusted odds ratio 1·52; 95% CI 1·19-1·95), and transitional case management (1·65; 1·36-1·99), receipt of antiretroviral therapy during incarceration (1·39; 1·11-1·74), and two or more medical comorbidities (1·86; 1·48-2·36). Reincarceration (0·70; 0·56-0·88) and conditional release (0·62; 0·50-0·78) were negatively associated with LTC within 14 days. Hispanic ethnicity, bonded release, and psychiatric comorbidity were also associated with LTC within 30 days but reincarceration was not.

    INTERPRETATION: LTC after release is suboptimal but improves when inmates' medical, psychiatric, and case management needs are identified and addressed before release. People who are rapidly cycling through jail facilities are particularly vulnerable to missed linkage opportunities. The use of integrated programmes to align justice and health-care goals has great potential to improve long-term HIV treatment outcomes.

    FUNDING: US National Institutes of Health.

    Matched MeSH terms: Viral Load
  20. Vignesh R, Swathirajan CR, Solomon SS, Shankar EM, Murugavel KG
    Indian J Med Microbiol, 2017 Apr-Jun;35(2):279-281.
    PMID: 28681821 DOI: 10.4103/ijmm.IJMM_16_163
    Immune reconstitution inflammatory syndrome (IRIS) continues to be a complication in HIV/tuberculosis (TB) co-infected patients initiating highly active antiretroviral therapy (HAART). The aim of this study was to evaluate the risk factors associated with developing IRIS to identify a possible biomarker to predict or diagnose IRIS in patients initiating HAART. A total of 175 HIV/TB co-infected patients initiating HAART were followed up longitudinally during September 2010 to May 2013 attending a HIV care clinic in Chennai. Patients were followed up longitudinally after HAART initiation and baseline demographic, laboratory parameters and treatment characteristics between patients with IRIS events and those without IRIS events were compared. Chi-square or Fisher's exact test for categorical variables and a Wilcoxon rank-sum test for continuous variables were performed using SPSS, version 12.0 software. Patients with IRIS had a significantly lower median baseline CD4+ T-cell count (P = 0.0039). There were no differences in terms of sex, CD4 T-cell %, plasma viral load, time interval between initiating ATT and HAART between the IRIS and non-IRIS patients. Low CD4+ T-cell count (<100 cells/μL) could be used as a marker to screen and monitor patients initiating HAART.
    Matched MeSH terms: Viral Load
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