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Graphene for Biosensing Applications in Point-of-Care Testing 总被引:1,自引:0,他引:1
《Trends in biotechnology》2021,39(10):1065-1077
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Du-Ping Zheng Margarida Rodrigues Ebi Bile Duc B. Nguyen Karidia Diallo Joshua R. DeVos John N. Nkengasong Chunfu Yang 《PloS one》2013,8(10)
Detection of recent HIV infections is a prerequisite for reliable estimations of transmitted HIV drug resistance (t-HIVDR) and incidence. However, accurately identifying recent HIV infection is challenging due partially to the limitations of current serological tests. Ambiguous nucleotides are newly emerged mutations in quasispecies, and accumulate by time of viral infection. We utilized ambiguous mutations to establish a measurement for detecting recent HIV infection and monitoring early HIVDR development. Ambiguous nucleotides were extracted from HIV-1 pol-gene sequences in the datasets of recent (HIVDR threshold surveys [HIVDR-TS] in 7 countries; n=416) and established infections (1 HIVDR monitoring survey at baseline; n=271). An ambiguous mutation index of 2.04×10-3 nts/site was detected in HIV-1 recent infections which is equivalent to the HIV-1 substitution rate (2×10-3 nts/site/year) reported before. However, significantly higher index (14.41×10-3 nts/site) was revealed with established infections. Using this substitution rate, 75.2% subjects in HIVDR-TS with the exception of the Vietnam dataset and 3.3% those in HIVDR-baseline were classified as recent infection within one year. We also calculated mutation scores at amino acid level at HIVDR sites based on ambiguous or fitted mutations. The overall mutation scores caused by ambiguous mutations increased (0.54×10-23.48×10-2/DR-site) whereas those caused by fitted mutations remained stable (7.50-7.89×10-2/DR-site) in both recent and established infections, indicating that t-HIVDR exists in drug-naïve populations regardless of infection status in which new HIVDR continues to emerge. Our findings suggest that characterization of ambiguous mutations in HIV may serve as an additional tool to differentiate recent from established infections and to monitor HIVDR emergence. 相似文献
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高效抗逆转录病毒治疗法(HAART)的推广使用有效地抑制了HIV-1病毒的传播和艾滋病(AIDS)的发病率、死亡率。近年来,HIV-1逆转录酶基因突变所导致的耐药性成为了HAART的治疗失败的主要原因,耐药性突变的检测对于指导病人用药以及新药开发具有重要意义。本工作发展了一种检测HIV-1逆转录酶基因耐药性突变的新方法。采用两步MS-PCR方法检测HIV-1 B亚型野生型和耐药突变型逆转录酶基因突变,检测点包括M41L、K70R、K103N、Y181C和T215,并在两步MS-PCR基础上,设计比野生型引物长的突变型引物,结合微孔板杂交ELISA呈色技术检测各点突变。结果显示,简化的两步MS-PCR能保持灵敏度和特异性高的优点,ELISA的阳性结果与阴性结果的比值(P/N)达到要求,两步MS-PCR结合ELISA方法灵敏度高,操作简单、结果直观、成本低、相对耗时短且能进行高通量检测,其无论在HIV-1耐药性突变及其它的点突变检测中具有较好的临床应用前景。 相似文献
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Wan-Lin Yang Roger D. Kouyos Jürg B?ni Sabine Yerly Thomas Klimkait Vincent Aubert Alexandra U. Scherrer Mohaned Shilaih Trevor Hinkley Christos Petropoulos Sebastian Bonhoeffer Huldrych F. Günthard the Swiss HIV Cohort Study 《PLoS pathogens》2015,11(3)
Transmission of drug-resistant pathogens presents an almost-universal challenge for fighting infectious diseases. Transmitted drug resistance mutations (TDRM) can persist in the absence of drugs for considerable time. It is generally believed that differential TDRM-persistence is caused, at least partially, by variations in TDRM-fitness-costs. However, in vivo epidemiological evidence for the impact of fitness costs on TDRM-persistence is rare.Here, we studied the persistence of TDRM in HIV-1 using longitudinally-sampled nucleotide sequences from the Swiss-HIV-Cohort-Study (SHCS). All treatment-naïve individuals with TDRM at baseline were included. Persistence of TDRM was quantified via reversion rates (RR) determined with interval-censored survival models. Fitness costs of TDRM were estimated in the genetic background in which they occurred using a previously published and validated machine-learning algorithm (based on in vitro replicative capacities) and were included in the survival models as explanatory variables.In 857 sequential samples from 168 treatment-naïve patients, 17 TDRM were analyzed. RR varied substantially and ranged from 174.0/100-person-years;CI=[51.4, 588.8] (for 184V) to 2.7/100-person-years;[0.7, 10.9] (for 215D). RR increased significantly with fitness cost (increase by 1.6[1.3,2.0] per standard deviation of fitness costs). When subdividing fitness costs into the average fitness cost of a given mutation and the deviation from the average fitness cost of a mutation in a given genetic background, we found that both components were significantly associated with reversion-rates.Our results show that the substantial variations of TDRM persistence in the absence of drugs are associated with fitness-cost differences both among mutations and among different genetic backgrounds for the same mutation. 相似文献
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Justen Manasa Siva Danaviah Sureshnee Pillay Prevashinee Padayachee Hloniphile Mthiyane Charity Mkhize Richard John Lessells Christopher Seebregts Tobias F. Rinke de Wit Johannes Viljoen David Katzenstein Tulio De Oliveira 《Journal of visualized experiments : JoVE》2014,(85)
HIV-1 drug resistance has the potential to seriously compromise the effectiveness and impact of antiretroviral therapy (ART). As ART programs in sub-Saharan Africa continue to expand, individuals on ART should be closely monitored for the emergence of drug resistance. Surveillance of transmitted drug resistance to track transmission of viral strains already resistant to ART is also critical. Unfortunately, drug resistance testing is still not readily accessible in resource limited settings, because genotyping is expensive and requires sophisticated laboratory and data management infrastructure. An open access genotypic drug resistance monitoring method to manage individuals and assess transmitted drug resistance is described. The method uses free open source software for the interpretation of drug resistance patterns and the generation of individual patient reports. The genotyping protocol has an amplification rate of greater than 95% for plasma samples with a viral load >1,000 HIV-1 RNA copies/ml. The sensitivity decreases significantly for viral loads <1,000 HIV-1 RNA copies/ml. The method described here was validated against a method of HIV-1 drug resistance testing approved by the United States Food and Drug Administration (FDA), the Viroseq genotyping method. Limitations of the method described here include the fact that it is not automated and that it also failed to amplify the circulating recombinant form CRF02_AG from a validation panel of samples, although it amplified subtypes A and B from the same panel. 相似文献
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Felix DeAnda Kendra E. Hightower Robert T. Nolte Kazunari Hattori Tomokazu Yoshinaga Takashi Kawasuji Mark R. Underwood 《PloS one》2013,8(10)
Signature HIV-1 integrase mutations associated with clinical raltegravir resistance involve 1 of 3 primary genetic pathways, Y143C/R, Q148H/K/R and N155H, the latter 2 of which confer cross-resistance to elvitegravir. In accord with clinical findings, in vitro drug resistance profiling studies with wild-type and site-directed integrase mutant viruses have shown significant fold increases in raltegravir and elvitegravir resistance for the specified viral mutants relative to wild-type HIV-1. Dolutegravir, in contrast, has demonstrated clinical efficacy in subjects failing raltegravir therapy due to integrase mutations at Y143, Q148 or N155, which is consistent with its distinct in vitro resistance profile as dolutegravir’s antiviral activity against these viral mutants is equivalent to its activity against wild-type HIV-1. Kinetic studies of inhibitor dissociation from wild-type and mutant integrase-viral DNA complexes have shown that dolutegravir also has a distinct off-rate profile with dissociative half-lives substantially longer than those of raltegravir and elvitegravir, suggesting that dolutegravir’s prolonged binding may be an important contributing factor to its distinct resistance profile. To provide a structural rationale for these observations, we constructed several molecular models of wild-type and clinically relevant mutant HIV-1 integrase enzymes in complex with viral DNA and dolutegravir, raltegravir or elvitegravir. Here, we discuss our structural models and the posited effects that the integrase mutations and the structural and electronic properties of the integrase inhibitors may have on the catalytic pocket and inhibitor binding and, consequently, on antiviral potency in vitro and in the clinic. 相似文献
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为了解柳州和南宁两市HIV-1亚型分布和耐药情况,在柳州和南宁招募HIV感染者和AIDS患者共304名,采集外周静脉血,从血浆中提取HIVRNA,扩增HIVpol基因并测序。将获得的序列进行系统进化树分析,结果表明柳州的HIV-1毒株中存在CRF01_AE和CRF07_BC两种亚型,其中CRF01_AE毒株占75.2%,CRF07_BC毒株占24.8%;南宁的HIV-1毒株中存在CRF01_AE、CRF08_BC、B亚型和C亚型共4种亚型,其中CRF01_AE和CRF08_BC仍是南宁最主要的亚型,CRF01_AE占85.8%,CRF08_BC占11.5%。根据所得的序列资料进行HIV-1耐药性分析,计算耐药率。计算结果表明,柳州未治疗和治疗研究对象的耐药率分别为3.3%和8.7%,南宁未治疗和治疗研究对象的耐药率分别为1.4%和27.5%。 相似文献
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Background
Angola presents a very complex HIV-1 epidemic characterized by the co-circulation of several HIV-1 group M subtypes, intersubtype recombinants and unclassified (U) variants. The viral diversity outside the major metropolitan regions (Luanda and Cabinda) and the prevalence of transmitted drug resistance mutations (DRM) since the introduction of HAART in 2004, however, has been barely studied.Methods
One hundred and one individuals from the Central (n = 44), North (n = 35), and South (n = 22) regions of Angola were diagnosed as HIV-1 positive and had their blood collected between 2008 and 2010, at one of the National Referral Centers for HIV diagnosis, the Kifangondo Medical Center, located in the border between the Luanda and Bengo provinces. Angolan samples were genotyped based on phylogenetic and bootscanning analyses of the pol (PR/RT) gene and their drug resistance profile was analyzed.Results
Among the 101 samples analyzed, 51% clustered within a pure group M subtype, 42% were classified as intersubtype recombinants, and 7% were denoted as U. We observed an important variation in the prevalence of different HIV-1 genetic variants among country regions, with high frequency of subtype F1 in the North (20%), intersubtype recombinants in the Central (42%), and subtype C in the South (45%). Statistically significant difference in HIV-1 clade distribution was only observed in subtype C prevalence between North vs South (p = 0.0005) and Central vs South (p = 0.0012) regions. DRM to NRTI and/or NNRTI were detected in 16.3% of patients analyzed.Conclusions
These results demonstrate a heterogeneous distribution of HIV-1 genetic variants across different regions in Angola and also revealed an unexpected high frequency of DRM to RT inhibitors in patients that have reported no antiretroviral usage, which may decrease the efficiency of the standard first-line antiretroviral regimens currently used in the country. 相似文献16.
Dineke Frentz Charles A. B. Boucher Matthias Assel Andrea De Luca Massimiliano Fabbiani Francesca Incardona Pieter Libin Nino Manca Viktor Müller Breanndán ó. Nualláin Roger Paredes Mattia Prosperi Eugenia Quiros-Roldan Lidia Ruiz Peter M. A. Sloot Carlo Torti Anne-Mieke Vandamme Kristel Van Laethem Maurizio Zazzi David A. M. C. van de Vijver 《PloS one》2010,5(7)
Background
Several decision support systems have been developed to interpret HIV-1 drug resistance genotyping results. This study compares the ability of the most commonly used systems (ANRS, Rega, and Stanford''s HIVdb) to predict virological outcome at 12, 24, and 48 weeks.Methodology/Principal Findings
Included were 3763 treatment-change episodes (TCEs) for which a HIV-1 genotype was available at the time of changing treatment with at least one follow-up viral load measurement. Genotypic susceptibility scores for the active regimens were calculated using scores defined by each interpretation system. Using logistic regression, we determined the association between the genotypic susceptibility score and proportion of TCEs having an undetectable viral load (<50 copies/ml) at 12 (8–16) weeks (2152 TCEs), 24 (16–32) weeks (2570 TCEs), and 48 (44–52) weeks (1083 TCEs). The Area under the ROC curve was calculated using a 10-fold cross-validation to compare the different interpretation systems regarding the sensitivity and specificity for predicting undetectable viral load. The mean genotypic susceptibility score of the systems was slightly smaller for HIVdb, with 1.92±1.17, compared to Rega and ANRS, with 2.22±1.09 and 2.23±1.05, respectively. However, similar odds ratio''s were found for the association between each-unit increase in genotypic susceptibility score and undetectable viral load at week 12; 1.6 [95% confidence interval 1.5–1.7] for HIVdb, 1.7 [1.5–1.8] for ANRS, and 1.7 [1.9–1.6] for Rega. Odds ratio''s increased over time, but remained comparable (odds ratio''s ranging between 1.9–2.1 at 24 weeks and 1.9–2.2 at 48 weeks). The Area under the curve of the ROC did not differ between the systems at all time points; p = 0.60 at week 12, p = 0.71 at week 24, and p = 0.97 at week 48.Conclusions/Significance
Three commonly used HIV drug resistance interpretation systems ANRS, Rega and HIVdb predict virological response at 12, 24, and 48 weeks, after change of treatment to the same extent. 相似文献17.
Isabel Inês M. de Pina-Araujo Monick L. Guimar?es Gonzalo Bello Ana Carolina P. Vicente Mariza G. Morgado 《PloS one》2014,9(4)
HIV-1 and HIV-2 have been detected in Cape Verde since 1987, but little is known regarding the genetic diversity of these viruses in this archipelago, located near the West African coast. In this study, we characterized the molecular epidemiology of HIV-1 and HIV-2 and described the occurrence of drug resistance mutations (DRM) among antiretroviral therapy naïve (ARTn) patients and patients under treatment (ARTexp) from different Cape Verde islands. Blood samples, socio-demographic and clinical-laboratory data were obtained from 221 HIV-positive individuals during 2010–2011. Phylogenetic and bootscan analyses of the pol region (1300 bp) were performed for viral subtyping. HIV-1 and HIV-2 DRM were evaluated for ARTn and ARTexp patients using the Stanford HIV Database and HIV-GRADE e.V. Algorithm Homepage, respectively. Among the 221 patients (169 [76.5%] HIV-1, 43 [19.5%] HIV-2 and 9 [4.1%] HIV-1/HIV-2 co-infections), 67% were female. The median ages were 34 (IQR = 1–75) and 47 (IQR = 12–84) for HIV-1 and HIV-2, respectively. HIV-1 infections were due to subtypes G (36.6%), CRF02_AG (30.6%), F1 (9.7%), URFs (10.4%), B (5.2%), CRF05_DF (3.0%), C (2.2%), CRF06_cpx (0.7%), CRF25_cpx (0.7%) and CRF49_cpx (0.7%), whereas all HIV-2 infections belonged to group A. Transmitted DRM (TDRM) was observed in 3.4% (2/58) of ARTn HIV-1-infected patients (1.7% NRTI, 1.7% NNRTI), but not among those with HIV-2. Among ARTexp patients, DRM was observed in 47.8% (33/69) of HIV-1 (37.7% NRTI, 37.7% NNRTI, 7.4% PI, 33.3% for two classes) and 17.6% (3/17) of HIV-2-infections (17.6% NRTI, 11.8% PI, 11.8% both). This study indicates that Cape Verde has a complex and unique HIV-1 molecular epidemiological scenario dominated by HIV-1 subtypes G, CRF02_AG and F1 and HIV-2 subtype A. The occurrence of TDRM and the relatively high level of DRM among treated patients are of concern. Continuous monitoring of patients on ART, including genotyping, are public policies to be implemented. 相似文献
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Saleta Sierra J. Nikolai Dybowski Alejandro Pironti Dominik Heider Lisa Güney Alex Thielen Stefan Reuter Stefan Esser Gerd F?tkenheuer Thomas Lengauer Daniel Hoffmann Herbert Pfister Bj?rn Jensen Rolf Kaiser 《PloS one》2015,10(5)
ObjectivesWe analysed the impact of different parameters on genotypic tropism testing related to clinical outcome prediction in 108 patients on maraviroc (MVC) treatment.Methods87 RNA and 60 DNA samples were used. The viral tropism was predicted using the geno2pheno[coreceptor] and T-CUP tools with FPR cut-offs ranging from 1%-20%. Additionally, 27 RNA and 28 DNA samples were analysed in triplicate, 43 samples with the ESTA assay and 45 with next-generation sequencing. The influence of the genotypic susceptibility score (GSS) and 16 MVC-resistance mutations on clinical outcome was also studied.ResultsConcordance between single-amplification testing compared to ESTA and to NGS was in the order of 80%. Concordance with NGS was higher at lower FPR cut-offs. Detection of baseline R5 viruses in RNA and DNA samples by all methods significantly correlated with treatment success, even with FPR cut-offs of 3.75%-7.5%. Triple amplification did not improve the prediction value but reduced the number of patients eligible for MVC. No influence of the GSS or MVC-resistance mutations but adherence to treatment, on the clinical outcome was detected.ConclusionsProviral DNA is valid to select candidates for MVC treatment. FPR cut-offs of 5%-7.5% and single amplification from RNA or DNA would assure a safe administration of MVC without excluding many patients who could benefit from this drug. In addition, the new prediction system T-CUP produced reliable results. 相似文献
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Elizabeth P. St. John Birgitte B. Simen Gregory S. Turenchalk Michael S. Braverman Isabella Abbate Jeroen Aerssens Olivier Bouchez Christian Gabriel Jacques Izopet Karolin Meixenberger Francesca Di Giallonardo Ralph Schlapbach Roger Paredes James Sakwa Gudrun G. Schmitz-Agheguian Alexander Thielen Martin Victor Karin J. Metzner Martin P. D?umer HIV- Alpha Study Group 《PloS one》2016,11(1)
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Inês Bártolo Suzana Zakovic Francisco Martin Claudia Palladino Patrícia Carvalho Ricardo Camacho Sven Thamm Sofia Clemente Nuno Taveira 《PloS one》2014,9(12)