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1.
J Antimicrob Chemother ; 79(2): 339-348, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38153241

RESUMO

BACKGROUND: Maintenance monotherapy with ritonavir-boosted darunavir has yielded variable outcomes and is not recommended. Trial samples offer valuable opportunities for detailed studies. We analysed samples from a 48 week trial in Cameroon to obtain a detailed characterization of drug resistance. METHODS: Following failure of NNRTI-based therapy and virological suppression on PI-based therapy, participants were randomized to ritonavir-boosted darunavir (n = 81) or tenofovir disoproxil fumarate/lamivudine +ritonavir-boosted lopinavir (n = 39). At study entry, PBMC-derived HIV-1 DNA underwent bulk Protease and Reverse Transcriptase (RT) sequencing. At virological rebound (confirmed or last available HIV-1 RNA ≥ 60 copies/mL), plasma HIV-1 RNA underwent ultradeep Protease and RT sequencing and bulk Gag-Protease sequencing. The site-directed mutant T375A (p2/p7) was characterized phenotypically using a single-cycle assay. RESULTS: NRTI and NNRTI resistance-associated mutations (RAMs) were detected in 52/90 (57.8%) and 53/90 (58.9%) HIV-1 DNA samples, respectively. Prevalence in rebound HIV-1 RNA (ritonavir-boosted darunavir, n = 21; ritonavir-boosted lopinavir, n = 2) was 9/23 (39.1%) and 10/23 (43.5%), respectively, with most RAMs detected at frequencies ≥15%. The resistance patterns of paired HIV-1 DNA and RNA sequences were partially consistent. No darunavir RAMs were found. Among eight participants experiencing virological rebound on ritonavir-boosted darunavir (n = 12 samples), all had Gag mutations associated with PI exposure, including T375N, T375A (p2/p7), K436R (p7/p1) and substitutions in p17, p24, p2 and p6. T375A conferred 10-fold darunavir resistance and increased replication capacity. CONCLUSIONS: The study highlights the high resistance barrier of ritonavir-boosted darunavir while identifying alternative pathways of resistance through Gag substitutions. During virological suppression, resistance patterns in HIV-1 DNA reflect treatment history, but due to technical and biological considerations, cautious interpretation is warranted.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Inibidores da Protease de HIV , Humanos , Darunavir/farmacologia , Darunavir/uso terapêutico , Ritonavir/farmacologia , Ritonavir/uso terapêutico , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Lopinavir/farmacologia , Lopinavir/uso terapêutico , Peptídeo Hidrolases/uso terapêutico , Leucócitos Mononucleares , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Inibidores da Protease de HIV/uso terapêutico , Mutação , RNA/uso terapêutico , DNA/uso terapêutico , Resistência a Medicamentos , Carga Viral
2.
Int J Mol Sci ; 24(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37108576

RESUMO

Prostate cancer is the second most diagnosed form of cancer in men worldwide and accounted for roughly 1.3 million cases and 359,000 deaths globally in 2018, despite all the available treatment strategies including surgery, radiotherapy, and chemotherapy. Finding novel approaches to prevent and treat prostate and other urogenital cancers effectively is of major importance. Chemicals derived from plants, such as docetaxel and paclitaxel, have been used in cancer treatment, and in recent years, research interest has focused on finding other plant-derived chemicals that can be used in the fight against cancer. Ursolic acid, found in high concentrations in cranberries, is a pentacyclic triterpenoid compound demonstrated to have anti-inflammatory, antioxidant, and anticancer properties. In the present review, we summarize the research studies examining the effects of ursolic acid and its derivatives against prostate and other urogenital cancers. Collectively, the existing data indicate that ursolic acid inhibits human prostate, renal, bladder, and testicular cancer cell proliferation and induces apoptosis. A limited number of studies have shown significant reduction in tumor volume in animals xenografted with human prostate cancer cells and treated with ursolic acid. More animal studies and human clinical studies are required to examine the potential of ursolic acid to inhibit prostate and other urogenital cancers in vivo.


Assuntos
Neoplasias da Próstata , Neoplasias Testiculares , Triterpenos , Masculino , Animais , Humanos , Neoplasias Testiculares/tratamento farmacológico , Próstata/patologia , Linhagem Celular Tumoral , Apoptose , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Proliferação de Células , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Ácido Ursólico
3.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37834041

RESUMO

Persistent high-risk human papillomavirus (HPV) infection is a pivotal factor in the progression of cervical cancer. In recent years, an increasing interest has emerged in comprehending the influence of HPV on head and neck squamous cell carcinoma (HNSCC). Notably, it is well established that HPV-associated HNSCC show cases with distinct molecular and clinical attributes compared to HPV-negative cases. The present study delves into the epigenetic landscape of HPV16, specifically its L1 gene and untranslated region (UTR), through pyrosequencing, while the HPV16 DNA physical status was evaluated using E2/E6 ratio analysis in HPV16-positive HNSCC FFPE biopsies. Our findings reveal substantial methylation across six sites within the HPV16 L1 gene and seven sites in the UTR. Specifically, methylation percentages of two L1 CpG sites (7136, 7145) exhibit significant associations with tumor histological grade (p < 0.01), while proving concurrent methylation across multiple sites. The HPV16 DNA physical status was not correlated with the methylation of viral genome or tumor characteristics. This is the first study that examines epigenetic modifications and the HPV16 DNA physical status in Greek HNSCC patients. Our findings suggest an orchestrated epigenetic modulation among specific sites, impacting viral gene expression and intricate virus-host interactions.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Feminino , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações , Papillomavirus Humano , Carcinoma de Células Escamosas/patologia , Metilação de DNA , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/complicações , DNA/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , DNA Viral/genética , DNA Viral/metabolismo
4.
Lancet ; 393(10189): 2428-2438, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31056293

RESUMO

BACKGROUND: The level of evidence for HIV transmission risk through condomless sex in serodifferent gay couples with the HIV-positive partner taking virally suppressive antiretroviral therapy (ART) is limited compared with the evidence available for transmission risk in heterosexual couples. The aim of the second phase of the PARTNER study (PARTNER2) was to provide precise estimates of transmission risk in gay serodifferent partnerships. METHODS: The PARTNER study was a prospective observational study done at 75 sites in 14 European countries. The first phase of the study (PARTNER1; Sept 15, 2010, to May 31, 2014) recruited and followed up both heterosexual and gay serodifferent couples (HIV-positive partner taking suppressive ART) who reported condomless sex, whereas the PARTNER2 extension (to April 30, 2018) recruited and followed up gay couples only. At study visits, data collection included sexual behaviour questionnaires, HIV testing (HIV-negative partner), and HIV-1 viral load testing (HIV-positive partner). If a seroconversion occurred in the HIV-negative partner, anonymised phylogenetic analysis was done to compare HIV-1 pol and env sequences in both partners to identify linked transmissions. Couple-years of follow-up were eligible for inclusion if condomless sex was reported, use of pre-exposure prophylaxis or post-exposure prophylaxis was not reported by the HIV-negative partner, and the HIV-positive partner was virally suppressed (plasma HIV-1 RNA <200 copies per mL) at the most recent visit (within the past year). Incidence rate of HIV transmission was calculated as the number of phylogenetically linked HIV infections that occurred during eligible couple-years of follow-up divided by eligible couple-years of follow-up. Two-sided 95% CIs for the incidence rate of transmission were calculated using exact Poisson methods. FINDINGS: Between Sept 15, 2010, and July 31, 2017, 972 gay couples were enrolled, of which 782 provided 1593 eligible couple-years of follow-up with a median follow-up of 2·0 years (IQR 1·1-3·5). At baseline, median age for HIV-positive partners was 40 years (IQR 33-46) and couples reported condomless sex for a median of 1·0 years (IQR 0·4-2·9). During eligible couple-years of follow-up, couples reported condomless anal sex a total of 76 088 times. 288 (37%) of 777 HIV-negative men reported condomless sex with other partners. 15 new HIV infections occurred during eligible couple-years of follow-up, but none were phylogenetically linked within-couple transmissions, resulting in an HIV transmission rate of zero (upper 95% CI 0·23 per 100 couple-years of follow-up). INTERPRETATION: Our results provide a similar level of evidence on viral suppression and HIV transmission risk for gay men to that previously generated for heterosexual couples and suggest that the risk of HIV transmission in gay couples through condomless sex when HIV viral load is suppressed is effectively zero. Our findings support the message of the U=U (undetectable equals untransmittable) campaign, and the benefits of early testing and treatment for HIV. FUNDING: National Institute for Health Research.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Soropositividade para HIV/transmissão , Homossexualidade Masculina , Sexo sem Proteção , Adulto , Terapia Antirretroviral de Alta Atividade , Preservativos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Parceiros Sexuais , Carga Viral
5.
Nutr Cancer ; 72(2): 320-332, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31274029

RESUMO

Prostate cancer is the second most commonly diagnosed cancer in men worldwide, which is almost incurable, once it progresses into the metastatic stage. Adriamycin (ADR) is a known chemotherapeutic agent that causes severe side effects. In recent years, studies in natural plant products have revealed their anticancer activities. In particular, Glycyrrhiza glabra enhanced extract (GGE), commonly known as licorice, has been reported to exert antiproliferative properties against cancer cells. In this study, the cytotoxic potential of GGE was assessed in PC-3 cells, when it is administrated alone or in combination with Adriamycin. PC-3 cells were treated with GGE and/or ADR, and the inhibition of cell proliferation was evaluated by the MTT assay. Cell cycle alterations and apoptosis rate were measured through flow cytometry. Expression levels of autophagy-related genes were evaluated with specific ELISA kits, Western blotting, and real-time PCR, while NMR spectrometry was used to identify the implication of specific metabolites. Our results demonstrated that GGE alone or in co-treatment with ADR shows antiproliferative properties against PC-3 cells, which are mediated by both apoptosis and autophagy mechanisms.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Doxorrubicina/farmacologia , Glycyrrhiza/química , Metaboloma/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Neoplasias da Próstata/tratamento farmacológico , Antibióticos Antineoplásicos/farmacologia , Apoptose , Autofagia , Proliferação de Células , Humanos , Masculino , Células PC-3 , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
6.
BMC Med ; 17(1): 4, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30616632

RESUMO

BACKGROUND: Knowledge of HIV-1 molecular transmission clusters (MTCs) is important, especially in large-scale datasets, for designing prevention programmes and public health intervention strategies. We used a large-scale HIV-1 sequence dataset from nine European HIV cohorts and one Canadian, to identify MTCs and investigate factors associated with the probability of belonging to MTCs. METHODS: To identify MTCs, we applied maximum likelihood inferences on partial pol sequences from 8955 HIV-positive individuals linked to demographic and clinical data. MTCs were defined using two different criteria: clusters with bootstrap support >75% (phylogenetic confidence criterion) and clusters consisting of sequences from a specific region at a proportion of >75% (geographic criterion) compared to the total number of sequences within the network. Multivariable logistic regression analysis was used to assess factors associated with MTC clustering. RESULTS: Although 3700 (41%) sequences belonged to MTCs, proportions differed substantially by country and subtype, ranging from 7% among UK subtype C sequences to 63% among German subtype B sequences. The probability of belonging to an MTC was independently less likely for women than men (OR = 0.66; P < 0.001), older individuals (OR = 0.79 per 10-year increase in age; P < 0.001) and people of non-white ethnicity (OR = 0.44; P < 0.001 and OR = 0.70; P = 0.002 for black and 'other' versus white, respectively). It was also more likely among men who have sex with men (MSM) than other risk groups (OR = 0.62; P < 0.001 and OR = 0.69; P = 0.002 for people who inject drugs, and sex between men and women, respectively), subtype B (ORs 0.36-0.70 for A, C, CRF01 and CRF02 versus B; all P < 0.05), having a well-estimated date of seroconversion (OR = 1.44; P < 0.001), a later calendar year of sampling (ORs 2.01-2.61 for all post-2002 periods versus pre-2002; all P < 0.01), and being naïve to antiretroviral therapy at sampling (OR = 1.19; P = 0.010). CONCLUSIONS: A high proportion (>40%) of individuals belonged to MTCs. Notably, the HIV epidemic dispersal appears to be driven by subtype B viruses spread within MSM networks. Expansion of regional epidemics seems mainly associated with recent MTCs, rather than the growth of older, established ones. This information is important for designing prevention and public health intervention strategies.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/genética , Infecções por HIV/transmissão , HIV-1/genética , Adulto , Canadá/epidemiologia , Epidemias , Europa (Continente)/epidemiologia , Feminino , Soropositividade para HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia
7.
Planta Med ; 85(11-12): 997-1007, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31288278

RESUMO

Silymarin-enriched extract (SEE) is obtained from Silybum marianum (Asteraceae). Doxorubicin (DXR) is a widely used chemotherapeutical yet with severe side effects. The goal of the present study was to assess the pharmacologic effect of SEE and its bioactive components silibinin and silychristine when administrated alone or in combination with DXR in the human prostate cancer cells (PC-3). PC-3 cells were treated with SEE, silibinin (silybins A and B), silychristine, alone, and in combination with DXR, and cell proliferation was assessed by the MTT assay. Cell cycle, apoptosis, and autophagy rate were assessed by flow cytometry. Expression levels of autophagy-related genes were quantified by qRT-PCR, ELISA and western blot while transmission electron microscopy was performed to reveal autophagic structures. Finally, NMR spectrometry was used to identify specific metabolites related to autophagy. SEE inhibited PC-3 cell proliferation in a dose-dependent manner while the co-treatment (DXR-SEE) revealed an additive cytotoxic effect. Cell cycle, apoptosis, and autophagy variations were observed in addition to altered expression levels of autophagy related genes (LC3, p62, NBR1, Beclin1, ULK1, AMBRA1), while several modifications in autophagic structures were identified after DXR-SEE co-treatment. Furthermore, treated cells showed a different metabolic profile, with significant alterations in autophagy-related metabolites such as branched-chain amino acids. In conclusion, the DXR-SEE co-treatment provokes perturbations in the autophagic mechanism of prostate cancer cells (PC-3) compared to DXR treatment alone, causing an excessive cell death. These findings propose the putative use of SEE as an adjuvant cytotoxic agent.


Assuntos
Doxorrubicina/uso terapêutico , Extratos Vegetais/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Silybum marianum/química , Silimarina/uso terapêutico , Western Blotting , Sinergismo Farmacológico , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Masculino , Células PC-3/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Silimarina/isolamento & purificação
8.
Am J Respir Crit Care Med ; 197(12): 1604-1615, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29365279

RESUMO

RATIONALE: People living with HIV are at significantly increased risk of invasive pneumococcal disease, despite long-term antiretroviral therapy (ART). The mechanism explaining this observation remains undefined. OBJECTIVES: To determine if apoptosis-associated microbicidal mechanisms, required to clear intracellular pneumococci that survive initial phagolysosomal killing, are perturbed. METHODS: Alveolar macrophages (AM) were obtained by BAL from healthy donors or HIV-1-seropositive donors on long-term ART with undetectable plasma viral load. Monocyte-derived macrophages (MDM) were obtained from healthy donors and infected with HIV-1BaL or treated with gp120. Macrophages were challenged with opsonized serotype 2 Streptococcus pneumoniae and assessed for apoptosis, bactericidal activity, protein expression, and mitochondrial reactive oxygen species (mROS). AM phenotyping, ultrasensitive HIV-1 RNA quantification, and gp120 measurement were also performed in BAL. MEASUREMENTS AND MAIN RESULTS: HIV-1BaL infection impaired apoptosis, induction of mROS, and pneumococcal killing by MDM. Apoptosis-associated pneumococcal killing was also reduced in AM from ART-treated HIV-1-seropositive donors. BAL fluid from these individuals demonstrated persistent lung CD8+ T lymphocytosis, and gp120 or HIV-1 RNA was also detected. Despite this, transcriptional activity in AM freshly isolated from people living with HIV was broadly similar to healthy volunteers. Instead, gp120 phenocopied the defect in pneumococcal killing in healthy MDM through post-translational modification of Mcl-1, preventing apoptosis induction, caspase activation, and increased mROS generation. Moreover, gp120 also inhibited mROS-dependent pneumococcal killing in MDM. CONCLUSIONS: Despite ART, HIV-1, via gp120, drives persisting innate immune defects in AM microbicidal mechanisms, enhancing susceptibility to pneumococcal disease.


Assuntos
Antirretrovirais/efeitos adversos , Antirretrovirais/uso terapêutico , Resistência à Doença/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Pneumopatias/imunologia , Macrófagos Alveolares/imunologia , Infecções Pneumocócicas/imunologia , Adulto , Feminino , Proteína gp120 do Envelope de HIV/sangue , Humanos , Pneumopatias/microbiologia , Pneumopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/fisiopatologia
10.
J Antimicrob Chemother ; 73(11): 3148-3157, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30032305

RESUMO

Objectives: The resistance profiles of patients receiving long-term ART in sub-Saharan Africa have been poorly described. This study obtained a sensitive assessment of the resistance patterns associated with long-term tenofovir-based ART in a programmatic setting where virological monitoring is yet to become part of routine care. Methods: We studied subjects who, after a median of 4.2 years of ART, replaced zidovudine or stavudine with tenofovir disoproxil fumarate while continuing lamivudine and an NNRTI. Using deep sequencing, resistance-associated mutations (RAMs) were detected in stored samples collected at tenofovir introduction (T0) and after a median of 4.0 years (T1). Results: At T0, 19/87 (21.8%) subjects showed a detectable viral load and 8/87 (9.2%) had one or more major NNRTI RAMs, whereas 82/87 (94.3%) retained full tenofovir susceptibility. At T1, 79/87 (90.8%) subjects remained on NNRTI-based ART, 5/87 (5.7%) had introduced lopinavir/ritonavir due to immunological failure, and 3/87 (3.4%) had interrupted ART. Whilst 68/87 (78.2%) subjects maintained or achieved virological suppression between T0 and T1, a detectable viral load with NNRTI RAMs at T0 predicted lack of virological suppression at T1. Each treatment interruption, usually reflecting unavailability of the dispensary, doubled the risk of T1 viraemia. Tenofovir, lamivudine and efavirenz selected for K65R, K70E/T, L74I/V and Y115F, alongside M184V and multiple NNRTI RAMs; this resistance profile was accompanied by high viral loads and low CD4 cell counts. Conclusions: Viraemia on tenofovir, lamivudine and efavirenz led to complex resistance patterns with implications for continued drug activity and risk of onward transmission.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Tenofovir/uso terapêutico , Adulto , África Subsaariana , Alcinos , Benzoxazinas/uso terapêutico , Ciclopropanos , Feminino , HIV-1/genética , Humanos , Lamivudina/uso terapêutico , Masculino , Mutação/efeitos dos fármacos , Inibidores da Transcriptase Reversa/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Carga Viral/efeitos dos fármacos , Viremia
11.
Microb Ecol ; 74(1): 78-88, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28032128

RESUMO

The recently described double-locus sequence typing (DLST) scheme implemented to deeply characterize the genetic profiles of 52 resistant environmental Pseudomonas aeruginosa isolates deriving from aquatic habitats of Greece. DLST scheme was able not only to assign an already known allelic profile to the majority of the isolates but also to recognize two new ones (ms217-190, ms217-191) with high discriminatory power. A third locus (oprD) was also used for the molecular typing, which has been found to be fundamental for the phylogenetic analysis of environmental isolates given the resulted increased discrimination between the isolates. Additionally, the circulation of acquired resistant mechanisms in the aquatic habitats according to their genetic profiles was proved to be more extent. Hereby, we suggest that the combination of the DLST to oprD typing can discriminate phenotypically and genetically related environmental P. aeruginosa isolates providing reliable phylogenetic analysis at a local level.


Assuntos
Ecossistema , Tipagem de Sequências Multilocus , Filogenia , Pseudomonas aeruginosa/classificação , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Grécia
12.
J Infect Dis ; 213(8): 1248-52, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26655301

RESUMO

Outcomes of chronic infection with hepatitis B virus (HBV) are varied, with increased morbidity reported in the context of human immunodeficiency virus (HIV) coinfection. The factors driving different outcomes are not well understood, but there is increasing interest in an HLA class I effect. We therefore studied the influence of HLA class I on HBV in an African HIV-positive cohort. We demonstrated that virologic markers of HBV disease activity (hepatitis B e antigen status or HBV DNA level) are associated with HLA-A genotype. This finding supports the role of the CD8(+) T-cell response in HBV control, and potentially informs future therapeutic T-cell vaccine strategies.


Assuntos
Coinfecção , Infecções por HIV , Antígenos HLA/genética , Antígenos E da Hepatite B/sangue , Hepatite B , Adulto , Estudos de Coortes , Coinfecção/complicações , Coinfecção/epidemiologia , Coinfecção/genética , Coinfecção/virologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/genética , Hepatite B/virologia , Humanos , Masculino , Prevalência , Curva ROC
13.
J Neurovirol ; 22(6): 852-860, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27194435

RESUMO

The central nervous system has been proposed as a sanctuary site where HIV can escape antiretroviral control and develop drug resistance. HIV-1 RNA can be at higher levels in CSF than plasma, termed CSF/plasma discordance. We aimed to examine whether discordance in CSF is associated with low level viraemia (LLV) in blood. In this MRC-funded multicentre study, we prospectively recruited patients with LLV, defined as one or more episode of unexplained plasma HIV-1 RNA within 12 months, and undertook CSF examination. Separately, we prospectively collected CSF from patients undergoing lumbar puncture for a clinical indication. Patients with durable suppression of viraemia and no evidence of CNS infection were identified as controls from this group. Factors associated with CSF/plasma HIV-1 discordance overall were examined. One hundred fifty-three patients were recruited across 13 sites; 40 with LLV and 113 undergoing clinical lumbar puncture. Seven of the 40 (18 %) patients with LLV had CSF/plasma discordance, which was significantly more than 0/43 (0 %) with durable suppression in blood from the clinical group (p = 0.005). Resistance associated mutations were shown in six CSF samples from discordant patients with LLV (one had insufficient sample for testing), which affected antiretroviral therapy at sampling in five. Overall discordance was present in 20/153 (13 %) and was associated with nadir CD4 but not antiretroviral concentrations in plasma or CSF. CSF/plasma discordance is observed in patients with LLV and is associated with antiretroviral resistance associated mutations in CSF. The implications for clinical practice require further investigation.


Assuntos
Infecções por HIV/diagnóstico , RNA Viral/sangue , RNA Viral/líquido cefalorraquidiano , Viremia/diagnóstico , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Sistema Nervoso Central/virologia , Farmacorresistência Viral/genética , Feminino , Infecções por HIV/sangue , Infecções por HIV/líquido cefalorraquidiano , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/crescimento & desenvolvimento , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , RNA Viral/antagonistas & inibidores , Viremia/sangue , Viremia/líquido cefalorraquidiano , Viremia/tratamento farmacológico
14.
Cytokine ; 83: 139-146, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27131579

RESUMO

INTRODUCTION: HIV-1 RNA can be found at higher levels in cerebrospinal fluid (CSF) than in plasma, termed CSF/plasma discordance. The clinical significance of CSF/plasma discordance is not known and the degree of discordance considered important varies. We aimed to determine whether a panel of CSF cytokines, chemokines and associated mediators were raised in patients with CSF/plasma discordance at different levels. METHODS: A nested case-control study of 40 CSF samples from the PARTITION study. We used a cytometric bead array to measure CSF mediator concentrations in 19 discordant and 21 non-discordant samples matched for plasma HIV-1 RNA. Discordant samples were subdivided into 'high discordance' (>1log10) and 'low discordance' (0.5-1log10, or ultrasensitive discordance). CSF mediators significant in univariate analysis went forward to two-way unsupervised hierarchical clustering based on the patterns of relative mediator concentrations. RESULTS: In univariate analysis 19 of 21 CSF mediators were significantly higher in discordant than non-discordant samples. There were no significant differences between samples with high versus low discordance. The samples grouped into two clusters which corresponded to CSF/plasma discordance (p<0.0001). In cluster one all mediators had relatively high abundance; this included 18 discordant samples and three non-discordant samples. In cluster two all mediators had relatively low abundance; this included 18 non-discordant samples and one non-discordant sample with ultrasensitive discordance only. CONCLUSIONS: CSF/plasma discordance is associated with potentially damaging neuroinflammatory process. Patients with discordance at lower levels (ie. 0.5-1log10) should also be investigated as mediator profiles were similar to those with discordance >1log10. Sensitive testing may have a role to determine whether ultrasensitive discordance is present in those with low level CSF escape.


Assuntos
Infecções por HIV , HIV-1 , Mediadores da Inflamação , RNA Viral , Adulto , Feminino , Infecções por HIV/sangue , Infecções por HIV/líquido cefalorraquidiano , Humanos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/biossíntese , RNA Viral/líquido cefalorraquidiano
15.
JAMA ; 316(2): 171-81, 2016 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-27404185

RESUMO

IMPORTANCE: A key factor in assessing the effectiveness and cost-effectiveness of antiretroviral therapy (ART) as a prevention strategy is the absolute risk of HIV transmission through condomless sex with suppressed HIV-1 RNA viral load for both anal and vaginal sex. OBJECTIVE: To evaluate the rate of within-couple HIV transmission (heterosexual and men who have sex with men [MSM]) during periods of sex without condoms and when the HIV-positive partner had HIV-1 RNA load less than 200 copies/mL. DESIGN, SETTING, AND PARTICIPANTS: The prospective, observational PARTNER (Partners of People on ART-A New Evaluation of the Risks) study was conducted at 75 clinical sites in 14 European countries and enrolled 1166 HIV serodifferent couples (HIV-positive partner taking suppressive ART) who reported condomless sex (September 2010 to May 2014). Eligibility criteria for inclusion of couple-years of follow-up were condomless sex and HIV-1 RNA load less than 200 copies/mL. Anonymized phylogenetic analysis compared couples' HIV-1 polymerase and envelope sequences if an HIV-negative partner became infected to determine phylogenetically linked transmissions. EXPOSURES: Condomless sexual activity with an HIV-positive partner taking virally suppressive ART. MAIN OUTCOMES AND MEASURES: Risk of within-couple HIV transmission to the HIV-negative partner. RESULTS: Among 1166 enrolled couples, 888 (mean age, 42 years [IQR, 35-48]; 548 heterosexual [61.7%] and 340 MSM [38.3%]) provided 1238 eligible couple-years of follow-up (median follow-up, 1.3 years [IQR, 0.8-2.0]). At baseline, couples reported condomless sex for a median of 2 years (IQR, 0.5-6.3). Condomless sex with other partners was reported by 108 HIV-negative MSM (33%) and 21 heterosexuals (4%). During follow-up, couples reported condomless sex a median of 37 times per year (IQR, 15-71), with MSM couples reporting approximately 22,000 condomless sex acts and heterosexuals approximately 36,000. Although 11 HIV-negative partners became HIV-positive (10 MSM; 1 heterosexual; 8 reported condomless sex with other partners), no phylogenetically linked transmissions occurred over eligible couple-years of follow-up, giving a rate of within-couple HIV transmission of zero, with an upper 95% confidence limit of 0.30/100 couple-years of follow-up. The upper 95% confidence limit for condomless anal sex was 0.71 per 100 couple-years of follow-up. CONCLUSIONS AND RELEVANCE: Among serodifferent heterosexual and MSM couples in which the HIV-positive partner was using suppressive ART and who reported condomless sex, during median follow-up of 1.3 years per couple, there were no documented cases of within-couple HIV transmission (upper 95% confidence limit, 0.30/100 couple-years of follow-up). Additional longer-term follow-up is necessary to provide more precise estimates of risk.


Assuntos
Infecções por HIV/transmissão , HIV-1 , Comportamento Sexual , Parceiros Sexuais , Sexo sem Proteção , Adulto , Fármacos Anti-HIV/uso terapêutico , Preservativos , Europa (Continente) , Características da Família , Feminino , Soronegatividade para HIV , Soropositividade para HIV , HIV-1/classificação , HIV-1/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Estudos Prospectivos , RNA Viral , Risco , Carga Viral
16.
Clin Infect Dis ; 61(6): 883-91, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26021992

RESUMO

BACKGROUND: Antiretroviral treatment (ART) programs in sub-Saharan Africa have for many years included lamivudine as the sole hepatitis B virus (HBV) inhibitor. Long-term outcomes and the effects of introducing tenofovir as part of ART in these populations have not been characterized. METHODS: The study comprised a cross-sectional analysis of 106 human immunodeficiency virus (HIV)/HBV-coinfected subjects maintained on lamivudine, as well as a prospective analysis of 76 lamivudine-experienced subjects who introduced tenofovir. Patients underwent assessment of liver fibrosis by transient elastography (TE) and testing to characterize HIV type 1 (HIV-1) and HBV replication. RESULTS: After a median of 45 months of lamivudine treatment, HIV-1 RNA and HBV DNA were detectable in 35 of 106 (33.0%) and 54 of 106 (50.9%) subjects, respectively, with corresponding drug resistance rates of 17 of 106 (16.0%) and 31 of 106 (29.2%), respectively. Median TE values were 5.7 kPa (interquartile range, 4.7-7.2 kPa) and independently associated with HBV DNA load, aspartate aminotransferase levels, and platelet counts; 13 of 106 (12.3%) subjects had TE measurements >9.4 kPa. Twelve months after the first assessment, and a median of 7.8 months after introducing tenofovir, HBV DNA levels declined by a mean of 1.5 log10 IU/mL (P < .001). TE values changed by a mean of -0.2 kPa (P = .097), and declined significantly in subjects who had pretenofovir HBV DNA levels >2000 IU/mL (mean, -0.8 kPa; P = .048) or TE values >7.6 kPa (mean, -1.2 kPa; P = .021). HIV-1 RNA detection rates remained unchanged. CONCLUSIONS: A proportion of HIV/HBV-coinfected patients on long-term lamivudine-containing ART had poor HIV and HBV suppression, drug resistance, and TE values indicative of advanced liver fibrosis. Tenofovir improved HBV control and reduced liver stiffness in subjects with high HBV DNA load and TE values.


Assuntos
Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Infecções por HIV/complicações , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/tratamento farmacológico , Cirrose Hepática/epidemiologia , Tenofovir/uso terapêutico , Adulto , África Subsaariana , Estudos Transversais , Técnicas de Imagem por Elasticidade , Feminino , Gana , HIV-1/classificação , HIV-1/genética , HIV-1/isolamento & purificação , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/virologia , Humanos , Lamivudina/uso terapêutico , Cirrose Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Carga Viral
17.
J Antimicrob Chemother ; 70(12): 3311-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26324076

RESUMO

OBJECTIVES: Whether ART regimens differ in their propensity to allow persistent HIV-1 detection remains unclear. To investigate this, we performed a cross-sectional study to characterize HIV-1 persistence in peripheral blood during suppressive therapy with NRTIs plus a PI or nevirapine. METHODS: Residual plasma HIV-1 RNA was quantified by real-time PCR. Cell-associated proviral total HIV-1 DNA, unspliced and multiply spliced HIV-1 RNA and 2-long terminal repeat (2-LTR) circles were quantified by digital PCR. RESULTS: Comparing PI with nevirapine recipients, residual plasma HIV-1 RNA detection rates were 47/80 (58.8%) versus 37/81 (45.7%), with median (IQR) levels of 4 (3-8) versus 4 (3-7) copies/mL (P = 0.207); detection was less likely with longer duration of suppressive ART (P = 0.020), independently of treatment. HIV-1 DNA was detected in all patients, with median levels of 2.3 (IQR 2.0-2.7) versus 2.5 (IQR 2.1-2.7) log10 copies/10(6) PBMCs, respectively; HIV-1 DNA levels were associated with pre-ART viral load (P = 0.004) and with residual HIV-1 RNA (P = 0.034), unspliced HIV-1 RNA (P = 0.001) and 2-LTR circles (P = 0.005), independently of treatment. CONCLUSIONS: No significant differences were revealed in levels of residual plasma HIV-1 RNA, total HIV-1 DNA or intracellular markers of ongoing virus replication (unspliced and multiply spliced HIV-1 RNA and 2-LTR circles) between treatment groups.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , DNA Viral/sangue , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , RNA Viral/sangue , Carga Viral , Adulto , Estudos Transversais , Feminino , Inibidores da Protease de HIV/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Nevirapina/uso terapêutico , Reação em Cadeia da Polimerase , Resultado do Tratamento
18.
Clin Infect Dis ; 59(11): 1618-26, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25100867

RESUMO

BACKGROUND: It has been proposed that hepatitis B virus (HBV) sub-genotype A1 infections have mild outcomes and a low risk of drug-resistance among patients infected with human immunodeficiency virus (HIV) receiving lamivudine-containing antiretroviral therapy (ART) without tenofovir in Africa. METHODS: The virologic expression of HBV sub-genotype A1 coinfection was studied over 12 months in HIV-positive adults starting stavudine/lamivudine/nevirapine in Malawi, using Sanger, deep, clonal, and single full-genome sequencing for the sensitive characterization of HBV resistance-associated mutations (RAMs). RESULTS: Among 1117 subjects, 133 (12%) tested HBsAg-positive. After starting ART, retention rates were 96/133 (72%) at 6 months and 54/133 (41%) at 12 months. Based upon the last available follow-up, 92/96 (96%) subjects achieved HIV-1 RNA <40 copies/mL, 48/96 (50%) showed HBV DNA <14 IU/mL, and 24/96 (25%) acquired HBV RAMs. At 6 months, M204I was detected in 8/46 (17%) and 16/17 (94%) subjects using Sanger and deep sequencing, respectively. At 12 months, all viremic patients had multiple resistance and compensatory mutations coexisting on the same HBV genomes. Comparing HBeA-positive (67/133, 50%) with HBeAg-negative subjects, 64/67 (96%) vs 35/66 (55%) showed baseline HBV DNA >2000 IU/mL (P = .0006), 39/47 (17%) vs 9/49 (82%) had persistent HBV DNA detection during follow-up (P < .0001), and 23/47 (49%) vs 2/49 (4%) acquired HBV RAMs (P < .0001). Baseline HBV DNA levels were median 8.1 vs 5.3 log10 IU/mL in subjects with vs those without treatment-emergent RAMs (P < .0001). CONCLUSIONS: HBV sub-genotype A1 infections showed a severe virologic expression in HIV-positive Malawians. The findings strengthen the urgency of interventions to improve ascertainment and management of chronic hepatitis B in the region.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Vírus da Hepatite B/fisiologia , Hepatite B/virologia , Adulto , Fármacos Anti-HIV/efeitos adversos , DNA Viral/genética , Farmacorresistência Viral , Feminino , Infecções por HIV/virologia , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Humanos , Lamivudina/efeitos adversos , Lamivudina/uso terapêutico , Malaui , Masculino , Nevirapina/efeitos adversos , Nevirapina/uso terapêutico , Filogenia , Estudos Retrospectivos , Análise de Sequência de DNA , Estavudina/efeitos adversos , Estavudina/uso terapêutico , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
19.
Genes (Basel) ; 15(5)2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38790158

RESUMO

The evolutionary conserved Notch signaling pathway functions as a mediator of direct cell-cell communication between neighboring cells during development. Notch plays a crucial role in various fundamental biological processes in a wide range of tissues. Accordingly, the aberrant signaling of this pathway underlies multiple genetic pathologies such as developmental syndromes, congenital disorders, neurodegenerative diseases, and cancer. Over the last two decades, significant data have shown that the Notch signaling pathway displays a significant function in the mature brains of vertebrates and invertebrates beyond neuronal development and specification during embryonic development. Neuronal connection, synaptic plasticity, learning, and memory appear to be regulated by this pathway. Specific mutations in human Notch family proteins have been linked to several neurodegenerative diseases including Alzheimer's disease, CADASIL, and ischemic injury. Neurodegenerative diseases are incurable disorders of the central nervous system that cause the progressive degeneration and/or death of brain nerve cells, affecting both mental function and movement (ataxia). There is currently a lot of study being conducted to better understand the molecular mechanisms by which Notch plays an essential role in the mature brain. In this study, an in silico analysis of polymorphisms and mutations in human Notch family members that lead to neurodegenerative diseases was performed in order to investigate the correlations among Notch family proteins and neurodegenerative diseases. Particular emphasis was placed on the study of mutations in the Notch3 protein and the structure analysis of the mutant Notch3 protein that leads to the manifestation of the CADASIL syndrome in order to spot possible conserved mutations and interpret the effect of these mutations in the Notch3 protein structure. Conserved mutations of cysteine residues may be candidate pharmacological targets for the potential therapy of CADASIL syndrome.


Assuntos
CADASIL , Doenças Neurodegenerativas , Polimorfismo de Nucleotídeo Único , Receptores Notch , Humanos , CADASIL/genética , CADASIL/metabolismo , CADASIL/patologia , Receptores Notch/metabolismo , Receptores Notch/genética , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Mutação , Transdução de Sinais , Receptor Notch3/genética , Receptor Notch3/metabolismo
20.
Infect Genet Evol ; 121: 105597, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38663466

RESUMO

BACKGROUND: New diagnoses of HIV-1 infection among people who inject drugs (PWID) in Athens, Greece, saw a significant increase in 2011 and a subsequent decline after 2013. Despite this, ongoing HIV-1 transmission persisted from 2014 to 2020 within this population. Our objective was to estimate the time of infection for PWID in Athens following the HIV-1 outbreak, explore the patterns of HIV-1 dispersal over time, and determine the duration from infection to diagnosis. METHODS: Time from HIV-1 infection to diagnosis was estimated for 844 individuals infected within 4 PWID-specific clusters and for 8 PWID infected with sub-subtype A6 diagnosed during 2010-2019. Phylogeny reconstruction was performed using the maximum-likelihood method. HIV-1 infection dates were based on molecular clock calculations. RESULTS: In total 86 of 92 (93.5%) sequences from PWID diagnosed during 2016-2019 were either related to the previously identified PWID-specific clusters (n = 81) or belonged to a new A6 cluster (n = 5). The median time between infection and diagnosis was 0.42 years during the outbreak period and 0.70 years during 2016-2019 (p < 0.001). The proportion of clustered sequences from PWID was very low at 5.3% during the pre-outbreak period (1998-2009), saw an increase to 41.7% one year before the outbreak in 2010, and consistently remained high during the whole period after 2011, spanning the post-outbreak period (2016-2019) with a range from 92.9% to 100%. CONCLUSIONS: The substantial proportion of clustered infections (93.5%) during 2016-2019 implies a persistent 'slow burn' HIV outbreak among PWID in Athens, suggesting that the outbreak was not successfully eliminated. The consistently high proportion of clustered sequences since the onset of the outbreak suggests the persistence of ongoing HIV-1 transmission attributed to injection practices. Our findings underscore the importance of targeted interventions among PWID, considering the ongoing transmission rate and prolonged time from infection to diagnosis.


Assuntos
Surtos de Doenças , Infecções por HIV , HIV-1 , Epidemiologia Molecular , Filogenia , Abuso de Substâncias por Via Intravenosa , Humanos , Grécia/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Abuso de Substâncias por Via Intravenosa/complicações , HIV-1/genética , Masculino , Feminino , Adulto
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