Displaying publications 21 - 40 of 94 in total

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  1. Chong PP, Tung CH, Rahman NA, Yajima M, Chin FW, Yeng CL, et al.
    Acta Ophthalmol (Copenh), 2014 Nov;92(7):e569-79.
    PMID: 25043991 DOI: 10.1111/aos.12427
    The aim of the study was to determine the prevalence of human papillomavirus (HPV) in primary and recurrent pterygia samples collected from different ethnic groups in the equatorial Malay Peninsula.
    Matched MeSH terms: Viral Load*
  2. Kanapathipillai R, McManus H, Kamarulzaman A, Lim PL, Templeton DJ, Law M, et al.
    PLoS ONE, 2014;9(2):e86122.
    PMID: 24516527 DOI: 10.1371/journal.pone.0086122
    INTRODUCTION: Magnitude and frequency of HIV viral load blips in resource-limited settings, has not previously been assessed. This study was undertaken in a cohort from a high income country (Australia) known as AHOD (Australian HIV Observational Database) and another cohort from a mixture of Asian countries of varying national income per capita, TAHOD (TREAT Asia HIV Observational Database).

    METHODS: Blips were defined as detectable VL (≥ 50 copies/mL) preceded and followed by undetectable VL (<50 copies/mL). Virological failure (VF) was defined as two consecutive VL ≥50 copies/ml. Cox proportional hazard models of time to first VF after entry, were developed.

    RESULTS: 5040 patients (AHOD n = 2597 and TAHOD n = 2521) were included; 910 (18%) of patients experienced blips. 744 (21%) and 166 (11%) of high- and middle/low-income participants, respectively, experienced blips ever. 711 (14%) experienced blips prior to virological failure. 559 (16%) and 152 (10%) of high- and middle/low-income participants, respectively, experienced blips prior to virological failure. VL testing occurred at a median frequency of 175 and 91 days in middle/low- and high-income sites, respectively. Longer time to VF occurred in middle/low income sites, compared with high-income sites (adjusted hazards ratio (AHR) 0.41; p<0.001), adjusted for year of first cART, Hepatitis C co-infection, cART regimen, and prior blips. Prior blips were not a significant predictor of VF in univariate analysis (AHR 0.97, p = 0.82). Differing magnitudes of blips were not significant in univariate analyses as predictors of virological failure (p = 0.360 for blip 50-≤1000, p = 0.309 for blip 50-≤400 and p = 0.300 for blip 50-≤200). 209 of 866 (24%) patients were switched to an alternate regimen in the setting of a blip.

    CONCLUSION: Despite a lower proportion of blips occurring in low/middle-income settings, no significant difference was found between settings. Nonetheless, a substantial number of participants were switched to alternative regimens in the setting of blips.

    Matched MeSH terms: Viral Load*
  3. Grabowski MK, Gray RH, Serwadda D, Kigozi G, Gravitt PE, Nalugoda F, et al.
    Sex Transm Infect, 2014 Jun;90(4):337-43.
    PMID: 24482488 DOI: 10.1136/sextrans-2013-051230
    OBJECTIVES: High-risk human papillomavirus (HR-HPV) viral load is associated with HR-HPV transmission and HR-HPV persistence in women. It is unknown whether HR-HPV viral load is associated with persistence in HIV-negative or HIV-positive men.
    METHODS: HR-HPV viral load and persistence were evaluated among 703 HIV-negative and 233 HIV-positive heterosexual men who participated in a male circumcision trial in Rakai, Uganda. Penile swabs were tested at baseline and 6, 12 and 24 months for HR-HPV using the Roche HPV Linear Array, which provides a semiquantitative measure of HPV shedding by hybridisation band intensity (graded: 1-4). Prevalence risk ratios (PRR) were used to estimate the association between HR-HPV viral load and persistent detection of HR-HPV.
    RESULTS: HR-HPV genotypes with high viral load (grade:3-4) at baseline were more likely to persist than HR-HPV genotypes with low viral load (grade: 1-2) among HIV-negative men (month 6: adjPRR=1.83, 95% CI 1.32 to 2.52; month 12: adjPRR=2.01, 95% CI 1.42 to 3.11), and HIV-positive men (month 6: adjPRR=1.33, 95% CI 1.06 to 1.67; month 12: adjPRR=1.73, 95% CI 1.18 to 2.54). Long-term persistence of HR-HPV was more frequent among HIV-positive men compared with HIV-negative men (month 24: adjPRR=2.27, 95% CI 1.47 to 3.51). Persistence of newly detected HR-HPV at the 6-month and 12-month visits with high viral load were also more likely to persist to 24 months than HR-HPV with low viral load among HIV-negative men (adjPRR=1.67, 95% CI 0.88 to 3.16).
    CONCLUSIONS: HR-HPV genotypes with high viral load are more likely to persist among HIV-negative and HIV-positive men, though persistence was more common among HIV-positive men overall. The results may explain the association between high HR-HPV viral load and HR-HPV transmission.
    Matched MeSH terms: Viral Load*
  4. Kiertiburanakul S, Boettiger D, Ng OT, Van Kinh N, Merati TP, Avihingsanon A, et al.
    AIDS Res Ther, 2017;14:27.
    PMID: 28484509 DOI: 10.1186/s12981-017-0151-1
    BACKGROUND: Abacavir and rilpivirine are alternative antiretroviral drugs for treatment-naïve HIV-infected patients. However, both drugs are only recommended for the patients who have pre-treatment HIV RNA <100,000 copies/mL. In resource-limited settings, pre-treatment HIV RNA is not routinely performed and not widely available. The aims of this study are to determine factors associated with pre-treatment HIV RNA <100,000 copies/mL and to construct a model to predict this outcome.

    METHODS: HIV-infected adults enrolled in the TREAT Asia HIV Observational Database were eligible if they had an HIV RNA measurement documented at the time of ART initiation. The dataset was randomly split into a derivation data set (75% of patients) and a validation data set (25%). Factors associated with pre-treatment HIV RNA <100,000 copies/mL were evaluated by logistic regression adjusted for study site. A prediction model and prediction scores were created.

    RESULTS: A total of 2592 patients were enrolled for the analysis. Median [interquartile range (IQR)] age was 35.8 (29.9-42.5) years; CD4 count was 147 (50-248) cells/mm3; and pre-treatment HIV RNA was 100,000 (34,045-301,075) copies/mL. Factors associated with pre-treatment HIV RNA <100,000 copies/mL were age <30 years [OR 1.40 vs. 41-50 years; 95% confidence interval (CI) 1.10-1.80, p = 0.01], body mass index >30 kg/m2(OR 2.4 vs. <18.5 kg/m2; 95% CI 1.1-5.1, p = 0.02), anemia (OR 1.70; 95% CI 1.40-2.10, p 350 cells/mm3(OR 3.9 vs. <100 cells/mm3; 95% CI 2.0-4.1, p 2000 cells/mm3(OR 1.7 vs. <1000 cells/mm3; 95% CI 1.3-2.3, p 25 yielded the sensitivity of 46.7%, specificity of 79.1%, positive predictive value of 67.7%, and negative predictive value of 61.2% for prediction of pre-treatment HIV RNA <100,000 copies/mL among derivation patients.

    CONCLUSION: A model prediction for pre-treatment HIV RNA <100,000 copies/mL produced an area under the ROC curve of 0.70. A larger sample size for prediction model development as well as for model validation is warranted.

    Matched MeSH terms: Viral Load*
  5. McDonald EM, Duggal NK, Brault AC
    PLoS Negl Trop Dis, 2017 Oct;11(10):e0005990.
    PMID: 28985234 DOI: 10.1371/journal.pntd.0005990
    The Spondweni serogroup of viruses (Flaviviridae, Flavivirus) is comprised of Spondweni virus (SPONV) and Zika virus (ZIKV), which are mosquito-borne viruses capable of eliciting human disease. Numerous cases of ZIKV sexual transmission in humans have been documented following the emergence of the Asian genotype in the Americas. The African ZIKV genotype virus was previously implicated in the first reported case of ZIKV sexual transmission. Reports of SPONV infection in humans have been associated with non-specific febrile illness, but no association with sexual transmission has been reported. In order to assess the relative efficiency of sexual transmission of different ZIKV strains and the potential capacity of SPONV to be sexually transmitted, viral loads in the male reproductive tract and in seminal fluids were assessed in interferon α/β and -γ receptor deficient (AG129) mice. Male mice were inoculated subcutaneously with Asian genotype ZIKV strains PRVABC59 (Puerto Rico, 2015), FSS13025 (Cambodia, 2010), or P6-740 (Malaysia, 1966); African genotype ZIKV strain DakAr41524 (Senegal, 1984); or SPONV strain SAAr94 (South Africa, 1955). Infectious virus was detected in 60-72% of ejaculates collected from AG129 mice inoculated with ZIKV strains. In contrast, only 4% of ejaculates from SPONV-inoculated AG129 males were found to contain infectious virus, despite viral titers in the testes that were comparable to those of ZIKV-inoculated mice. Based on these results, future studies should be undertaken to assess the role of viral genetic determinants and host tropism that dictate the differential sexual transmission potential of ZIKV and SPONV.
    Matched MeSH terms: Viral Load*
  6. Rich KM, Wickersham JA, Valencia Huamaní J, Kiani SN, Cabello R, Elish P, et al.
    LGBT Health, 2019 3 16;5(8):477-483.
    PMID: 30874476 DOI: 10.1089/lgbt.2017.0186
    PURPOSE: Globally, transgender women (TGW) experience a high burden of adverse health outcomes, including a high prevalence of HIV and sexually transmitted infections (STIs) as well as psychiatric disorders and substance use disorders. To address gaps in HIV research in Peru focused specifically on TGW, this study presents characteristics of a sample of HIV-positive TGW and identifies factors associated with viral suppression.

    METHODS: Between June 2015 and August 2016, 50 HIV-positive TGW were recruited in Lima, Peru. Multivariable logistic regression was used to identify factors associated with viral suppression (<200 copies/mL) among the TGW.

    RESULTS: Among TGW, 85% achieved viral suppression. Approximately half (54%) reported anal sex with more than five partners in the past 6 months, 38% reported sex work, 68% had not disclosed their HIV status to one or more of their partners, and 38% reported condomless sex with their last partner. The prevalence of alcohol use disorders was high (54%), and 38% reported use of drugs in the past year. Moderate-to-severe drug use significantly reduced odds of achieving viral suppression (adjusted odds ratio 0.69; 95% confidence interval: 0.48-0.98).

    CONCLUSION: Our findings highlight the need for integrated treatment for substance disorders in HIV care to increase the viral suppression rate among TGW in Lima, Peru.

    Matched MeSH terms: Viral Load/statistics & numerical data*
  7. Hashim H, Sahari NS, Sazlly Lim SM, Hoo FK
    Iran Red Crescent Med J, 2015 Oct;17(10):e19546.
    PMID: 26568856 DOI: 10.5812/ircmj.19546
    INTRODUCTION: The introduction of highly active antiretroviral therapy (HAART), in 1996, has resulted in marked reductions in the rate of illness and death, due to HIV infection. The HAART has transformed HIV infection into a manageable chronic disease. However, although many regimens lower plasma viral load, to below the limit of detection, in most patients, maintaining viral load suppression remains challenging, because of adverse effects and toxicity in the long term, which can lead to non-adherence, virologic failure and drug resistance. Although rare, lactic acidosis often develops fatal complications, as reported in several human immunodeficiency virus infected patients treated with nucleoside reverse transcriptase inhibitors (NRTIs). The purpose of this paper is to report a case of tenofovir induced lactic acidosis and review the literature.

    CASE PRESENTATION: A 52-year-old Malay gentleman, with hepatitis C virus and HIV infection was admitted to the intensive care unit for severe lactic acidosis, with concurrent Escherichia coli bacteremia with multiorgan dysfunction. The patient was started on highly active antiretroviral therapy, which included tenofovir, 5 weeks before presentation. Antimicrobial therapy, continuous veno-venous hemofiltration, and other supportive treatments were instituted. However, the patient eventually succumbed to his illness.

    CONCLUSIONS: It is essential for clinicians to be able to recognize the signs and symptoms of lactic acidosis in NRTIs treated HIV patients, as an early diagnosis is important to institute treatment.

    Matched MeSH terms: Viral Load
  8. López M
    AIDS Rev, 2013 Jul-Sep;15(3):190-1.
    PMID: 24002204
    The 7th IAS Conference held in July 2013 in Kuala Lumpur, Malaysia, heard about a number of cases of "functional cure" in people who had started antiretroviral therapy soon after HIV infection, including a German case that can now be added to the "Mississippi baby" report presented at CROI 2012 and 14 individuals of the French VISCONTI cohort. All these persons maintained an undetectable viral load after coming off antiretrovirals.
    Matched MeSH terms: Viral Load
  9. Mohammed Saad, A.M., Mohammed Imad, A.M., Aini, H.H., Seman, M.R.
    MyJurnal
    Introduction: HCV infection is frequent in patients undergoing maintenance haemodialysis, with prevalence between 8 and 10%. Hepatitis C has an adverse effect on both patient and graft survival in those who get renal transplants. There are relatively scarce reports on the natural fluctuation in viral load level in patients on chronic haemodialysis. Materials and Methods: This is a longitudinal short-term three months study, where 27 chronic haemodialysis patients infected with known HCV genotypes were recruited from seven haemodialysis centres in Pahang. Serum samples were collected monthly, both pre- and post-haemodialysis sessions, over a period of three months. Viral RNA was extracted from serum using QIAamp Viral RNA Extraction kit (Qiagen). The HCV viral load was measured using one-step reverse transcriptase qPCR (Applied Biosystems) targeting the 5`HCV non-coding region (5’UTR). The serum α-IFN level was measured using commercial ELISA kit (Amersham, UK). Six biochemical liver function tests (AST, ALP, TP, albumin, ALT and TB) were also done for all pre-haemodialysis samples. Results: All patients showed persistent low level viral load that varied significantly over the study period (p = 0.001). HCV genotype 1 viral load was significantly higher than that of genotype 3. Conclusion: No apparent correlation could be recognized between the viral loads and the corresponding interferon-alpha levels which were detectable in only a few patients during the period of study.
    Matched MeSH terms: Viral Load
  10. Abiola, Abdulrahman Surajudeen, Lekhraj Rampal, Norlijah Othman, Faisal Ibrahim, Hayati Kadir@Shahar, Anuradha P. Radhakrishnan
    MyJurnal
    Adherence to antiretroviral therapy (ART) prevents disease progression, and the emergence of resistant mutations. It also reduces morbidity, and the necessity for more frequent, complicated regimens which are also relatively more expensive. Minimum adherence levels of 95% are required for treatment success. Poor adherence to treatment remains a stumbling block to the success of treatment programs. This generates major concerns about possible resistance of the human immunodeficiency virus (HIV) to the currently available ARVs. This paper aims to describe baseline results from a cohort of 242 Malaysian patients receiving ART within the context of an intervention aimed to improve adherence and treatment outcomes among patients initiating ART. A single-blinded Randomized Controlled Clinical Trial was conducted between January and December, 2014 in Hospital Sungai Buloh. Data on socio-demographic factors, clinical symptoms and adherence behavior of respondents was collected using modified, pre-validated Adult AIDS Clinical Trials Group (AACTG) adherence questionnaires. Baseline CD4 count, viral load, weight, full blood count, blood pressure, Liver function and renal profile tests were also conducted and recorded. Data was analyzed using SPSS version 22 and R software. Patients consisted of 215 (89%) males and 27 (11%) females. 117 (48%) were Malays, 98 (40%) were Chinese, 22 (9%) were Indians while 5 (2%) were of other ethnic minorities. The mean age for the intervention group was 32.1 ± 8.7 years while the mean age for the control group was 34.7 ± 9.5 years. Mean baseline adherence was 80.1 ± 19.6 and 85.1 ± 15.8 for the intervention and control groups respectively. Overall mean baseline CD4 count of patients was 222.97 ± 143.7 cells/mm³ while overall mean viral load was 255237.85 ± 470618.9. Patients had a mean weight of 61.55 ± 11.0 kg and 61.47 ± 12.3 kg in the intervention and control groups, respectively. Males account for about 90% of those initiating ART in the HIV clinic, at a relatively low CD4 count, high viral load and sub-optimal medication adherence levels at baseline.
    Matched MeSH terms: Viral Load
  11. Kim JH, Chong CK, Sinniah M, Sinnadurai J, Song HO, Park H
    J. Clin. Virol., 2015 Apr;65:11-9.
    PMID: 25766980 DOI: 10.1016/j.jcv.2015.01.018
    BACKGROUND: Dengue is a mosquito-borne disease that causes a public health problem in tropical and subtropical countries. Current immunological diagnostics based on IgM and/or nonstructural protein 1 (NS1) antigen are limited for acute dengue infection due to low sensitivity and accuracy.
    OBJECTIVES: This study aimed to develop a one-step multiplex real-time RT-PCR assay showing higher sensitivity and accuracy than previous approaches.
    STUDY DESIGN: Serotype-specific primers and probes were designed through the multiple alignment of NS1 gene. The linearity and limit of detection (LOD) of the assay were determined. The assay was clinically validated with an evaluation panel that was immunologically tested by WHO and Malaysian specimens.
    RESULTS: The LOD of the assay was 3.0 log10 RNA copies for DENV-1, 2.0 for DENV-3, and 1.0 for DENV-2 and DENV-4. The assay showed 95.2% sensitivity (20/21) in an evaluation panel, whereas NS1 antigen- and anti-dengue IgM-based immunological assays exhibited 0% and 23.8-47.6% sensitivities, respectively. The assay showed 100% sensitivity both in NS1 antigen- and anti-dengue IgM-positive Malaysian specimens (26/26). The assay provided the information of viral loads and serotype with discrimination of heterotypic mixed infection.
    CONCLUSIONS: The assay could be clinically applied to early dengue diagnosis, especially during the first 5 days of illness and approximately 14 days after infection showing an anti-dengue IgM-positive response.
    Matched MeSH terms: Viral Load
  12. Mok L, Wynne JW, Grimley S, Shiell B, Green D, Monaghan P, et al.
    J. Gen. Virol., 2015 Jul;96(Pt 7):1787-94.
    PMID: 25748429 DOI: 10.1099/vir.0.000112
    In recent years, bats have been identified as a natural reservoir for a diverse range of viruses. Nelson Bay orthoreovirus (NBV) was first isolated from the heart blood of a fruit bat (Pteropus poliocephalus) in 1968. While the pathogenesis of NBV remains unknown, other related members of this group have caused acute respiratory disease in humans. Thus the potential for NBV to impact human health appears plausible. Here, to increase our knowledge of NBV, we examined the replication and infectivity of NBV using different mammalian cell lines derived from bat, human, mouse and monkey. All cell lines supported the replication of NBV; however, L929 cells showed a greater than 2 log reduction in virus titre compared with the other cell lines. Furthermore, NBV did not induce major cytopathic effects in the L929 cells, as was observed in other cell lines. Interestingly, the related Pteropine orthoreoviruses, Pulau virus (PulV) and Melaka virus (MelV) were able to replicate to high titres in L929 cells but infection resulted in reduced cytopathic effect. Our study demonstrates a unique virus-host interaction between NBV and L929 cells, where cells effectively control viral infection/replication and limit the formation of syncytia. By elucidating the molecular mechanisms that control this unique relationship, important insights will be made into the biology of this fusogenic virus.
    Matched MeSH terms: Viral Load
  13. Kosalaraksa P, Boettiger DC, Bunupuradah T, Hansudewechakul R, Saramony S, Do VC, et al.
    J Pediatric Infect Dis Soc, 2017 Jun 01;6(2):173-177.
    PMID: 27295973 DOI: 10.1093/jpids/piw031
    Background.: Regular CD4 count testing is often used to monitor antiretroviral therapy efficacy. However, this practice may be redundant in children with a suppressed human immunodeficiency virus (HIV) viral load.

    Methods: Study end points were as follows: (1) a CD4 count <200 cells/mm3 followed by a CD4 count ≥200 cells/mm3 (transient CD4 <200); (2) CD4 count <200 cells/mm3 confirmed within 6 months (confirmed CD4 <200); and (3) a new or recurrent World Health Organization (WHO) stage 3 or 4 illness (clinical failure). Kaplan-Meier curves and Cox regression were used to evaluate rates and predictors of transient CD4 <200, confirmed CD4 <200, and clinical failure among virally suppressed children aged 5-15 years who were enrolled in the TREAT Asia Pediatric HIV Observational Database.

    Results: Data from 967 children were included in the analysis. At the time of confirmed viral suppression, median age was 10.2 years, 50.4% of children were female, and 95.4% were perinatally infected with HIV. Median CD4 cell count was 837 cells/mm3, and 54.8% of children were classified as having WHO stage 3 or 4 disease. In total, 18 transient CD4 <200 events, 2 confirmed CD4 <200 events, and10 clinical failures occurred at rates of 0.73 (95% confidence interval [95% CI], 0.46-1.16), 0.08 (95% CI, 0.02-0.32), and 0.40 (95% CI, 0.22-0.75) events per 100 patient-years, respectively. CD4 <500 cells/mm3 at the time of viral suppression confirmation was associated with higher rates of both CD4 outcomes.

    Conclusions: Regular CD4 testing may be unnecessary for virally suppressed children aged 5-15 years with CD4 ≥500 cells/mm3.

    Matched MeSH terms: Viral Load
  14. 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
  15. Barré-Sinoussi F, Abdool Karim SS, Albert J, Bekker LG, Beyrer C, Cahn P, et al.
    J Int AIDS Soc, 2018 07;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
  16. 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
  17. Tan TS, Sharifah Syed Hassan, Yap WB
    Sains Malaysiana, 2016;45:787-793.
    The use of cell lines such as Madin-Darby Canine Kidney (MDCK) and African Green Monkey Kidney (Vero) cells in
    influenza vaccine production is much advocated presently as a safer alternative to chicken embryonated eggs. It is
    thus essential to understand the influenza virus replication patterns in these cell lines prior to utilizing them in vaccine
    production. The infectivity of avian influenza A virus (A/Chicken/Malaysia/5858/2004) H5N1 in MDCK and Vero cell
    lines was first assessed by comparing the cytopathic effect (CPE) caused by the virus infection. The viral loads in both
    of the infected media and cells were also compared. The results showed that both of the MDCK and Vero cells began to
    exhibit significant CPE (p<0.05) after 48 h post-infection (h p.i). The MDCK cell line was more susceptible to the virus
    infection compared to Vero cell line throughout the incubation period. A higher viral load was also detected in the host
    cells compared to their respective culturing media. Interestingly, after reaching its maximum titer at 48 h p.i, the viral
    load in MDCK cells declined meanwhile the viral load in Vero cells increased gradually and peaked at 120 h p.i. Overall,
    both cell lines support efficient H5N1 virus replication. While the peak viral loads measured in the two cell lines did
    not differ much, a more rapid replication was observed in the infected MDCK samples. The finding showed that MDCK
    cell line might serve as a more time-saving and cost-effective cell culture-based system compared to Vero cell line for
    influenza vaccine production.
    Matched MeSH terms: Viral Load
  18. Mohd A, Zainal N, Tan KK, AbuBakar S
    Sci Rep, 2019 Oct 04;9(1):14336.
    PMID: 31586088 DOI: 10.1038/s41598-019-50674-3
    Zika virus (ZIKV) infection is a serious public health concern. ZIKV infection has been associated with increased occurrences of microcephaly among newborns and incidences of Guillain-Barré syndrome among adults. No specific therapeutics or vaccines are currently available to treat and protect against ZIKV infection. Here, a plant-secreted phytoalexin, resveratrol (RES), was investigated for its ability to inhibit ZIKV replication in vitro. Several RES treatment regimens were used. The ZIKV titers of mock- and RES-treated infected cell cultures were determined using the focus-forming assay and the Zika mRNA copy number as determined using qRT-PCR. Our results suggested that RES treatment reduced ZIKV titers in a dose-dependent manner. A reduction of >90% of virus titer and ZIKV mRNA copy number was achieved when infected cells were treated with 80 µM of RES post-infection. Pre-incubation of the virus with 80 µM RES showed >30% reduction in ZIKV titers and ZIKV mRNA copy number, implying potential direct virucidal effects of RES against the virus. The RES treatment reduced >70% virus titer in the anti-adsorption assay, suggesting the possibility that RES also interferes with ZIKV binding. However, there was no significant decrease in ZIKV titer when a short-period of RES treatment was applied to cells before ZIKV infection (pre-infection) and after the virus bound to the cells (virus internalization inhibition), implying that RES acts through its continuous presence in the cell cultures after virus infection. Overall, our results suggested that RES exhibited direct virucidal activity against ZIKV and possessed anti-ZIKV replication properties, highlighting the need for further exploration of RES as a potential antiviral molecule against ZIKV infection.
    Matched MeSH terms: Viral Load
  19. Mohamed Amin Z, Che Ani MA, Tan SW, Yeap SK, Alitheen NB, Syed Najmuddin SUF, et al.
    Sci Rep, 2019 Sep 30;9(1):13999.
    PMID: 31570732 DOI: 10.1038/s41598-019-50222-z
    The Newcastle disease virus (NDV) strain AF2240 is an avian avulavirus that has been demonstrated to possess oncolytic activity against cancer cells. However, to illicit a greater anti-cancer immune response, it is believed that the incorporation of immunostimulatory genes such as IL12 into a recombinant NDV backbone will enhance its oncolytic effect. In this study, a newly developed recombinant NDV that expresses IL12 (rAF-IL12) was tested for its safety, stability and cytotoxicity. The stability of rAF-IL12 was maintained when passaged in specific pathogen free (SPF) chicken eggs from passage 1 to passage 10; with an HA titer of 29. Based on the results obtained from the MTT cytotoxic assay, rAF-IL12 was determined to be safe as it only induced cytotoxic effects against normal chicken cell lines and human breast cancer cells while sparing normal cells. Significant tumor growth inhibition (52%) was observed in the rAF-IL12-treated mice. The in vivo safety profile of rAF-IL12 was confirmed through histological observation and viral load titer assay. The concentration and presence of the expressed IL12 was quantified and verified via ELISA assay. In summary, rAF-IL12 was proven to be safe, selectively replicating in chicken and cancer cells and was able to maintain its stability throughout several passages; thus enhancing its potential as an anti-breast cancer vaccine.
    Matched MeSH terms: Viral Load
  20. 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
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