Race Adjustment of Pulmonary Function Tests in the Diagnosis and Management of COPD: A Scoping Review.

Aim: Increasing evidence suggests that the inclusion of self-identified race in clinical decision algorithms may perpetuate longstanding inequities. Until recently, most pulmonary function tests utilized separate reference equations that are race/ethnicity based. Purpose: We assess the magnitude and scope of the available literature on the negative impact of race-based pulmonary function prediction equations on relevant outcomes in African Americans with COPD. Methods: We performed a scoping review utilizing an English language search on PubMed/Medline, Embase, Scopus, and Web of Science in September 2022 and updated it in December 2023. We searched for publications regarding the effect of race-specific vs race-neutral, race-free, or race-reversed lung function testing algorithms on the diagnosis of COPD and COPD-related physiologic and functional measures. Joanna Briggs Institute (JBI) guidelines were utilized for this scoping review. Eligibility criteria: The search was restricted to adults with COPD. We excluded publications on other lung disorders, non-English language publications, or studies that did not include African Americans. The search identified publications. Ultimately, six peer-reviewed publications and four conference abstracts were selected for this review. Results: Removal of race from lung function prediction equations often had opposite effects in African Americans and Whites, specifically regarding the severity of lung function impairment. Symptoms and objective findings were better aligned when race-specific reference values were not used. Race-neutral prediction algorithms uniformly resulted in reclassifying severity in the African Americans studied. Conclusion: The limited literature does not support the use of race-based lung function prediction equations. However, this assertion does not provide guidance for every specific clinical situation. For African Americans with COPD, the use of race-based prediction equations appears to fall short in enhancing diagnostic accuracy, classifying severity of impairment, or predicting subsequent clinical events. We do not have information comparing race-neutral vs race-based algorithms on prediction of progression of COPD. We conclude that the elimination of race-based reference values potentially reduces underestimation of disease severity in African Americans with COPD.

Quantitative detection of chikungunya, Zika, and dengue viruses by one-step real-time PCR in different cell substrates.

Chikungunya (CHIKV), Zika (ZIKV), and dengue viruses (DENV) are vector-borne pathogens that cause emerging and re-emerging epidemics throughout tropical and subtropical countries. The symptomatology is similar among these viruses and frequently co-circulates in the same areas, making the diagnosis arduous. Although there are different methods for detecting and quantifying pathogens, real-time reverse transcription-polymerase chain reaction (real-time RT-qPCR) has become a leading technique for detecting viruses. However, the currently developed assays frequently involve probes and high-cost reagents, limiting access in low-income countries. Therefore, this study aims to design and evaluate a quantitative one-step RT-qPCR assay to detect CHIKV, ZIKV, and DENV with high specificity, reproducibility, and low cost in multiple cell substrates. We established a DNA intercalating green dye-based RT-qPCR test that targets nsP1 of CHIKV, and NS5 gene of ZIKV, and DENV for the amplification reaction. The assay exhibited a high specificity confirmed by the melting curve analysis. No cross-reactivity was observed between the three viruses or unspecific amplification of host RNA. The sensitivity of the reaction was evaluated for each virus assay, getting a limit of detection of one RNA copy per virus. Standard curves were constructed, obtaining a reaction efficiency of ~ 100%, a correlation coefficient (R2) of ~ 0.97, and a slope of -3.3. The coefficient of variation (CV) ranged from 0.02 to 1.43. In addition, the method was optimized for viral quantification and tested in Vero, BHK-21, C6/36, LULO, and the Aedes cell lines. Thus, the DNA intercalating green dye-based RT-qPCR assay was a highly specific, sensitive, reproducible, and effective method for detecting and quantifying CHIKV, ZIKV, and DENV in different cell substrates that could also be applied in clinical samples.

Antiviral activity of myricetin glycosylated compounds isolated from Marcetia taxifolia against chikungunya virus.

The chikungunya virus (CHIKV) has produced epidemic outbreaks of significant public health impact. The clinical symptoms of this disease are fever, polyarthralgia, and skin rash, generally self-limiting, although patients may develop a chronic disabling condition or suffer lethal complications. Unfortunately, there is no specific treatment or vaccine available. Thus, the search for effective therapies to control CHIKV infection is an urgent need. This study evaluated the antiviral activity of flavonoids isolated from Marcetia taxifolia by in vitro and in silico analysis. Cytotoxicity of compounds was determined by MTT assay and viral load was assessed in cell substrates supernatants by plaque-forming and RT-qPCR assays. Selected molecules were analyzed by molecular docking assays. Myricetin 3-rhamnoside (MR) and myricetin 3-(6-rhamnosylgalactoside) (MRG) were tested for antiviral assays and analyzed by the TCID50 method and RT-qPCR. MR exhibited dose-dependent antiviral activity, reducing viral titer at concentrations of 150-18.8 µg/mL by at least 1-log. Similarly, MRG showed a significant decrease in viral titer at concentrations of 37.5, 9.4, and 2.3 µg/mL. RT-qPCR analysis also displayed a substantial reduction of CHIKV RNA for both flavonoids. Furthermore, molecular docking of the selected flavonoids proposed the nsP3 macrodomain as a possible target of action. Our study reveals that MR and MRG could be considered promising anti-CHIKV therapeutic agents. Molecular modeling studies showed MR and MRG ligands with a high affinity for the N-terminal region of the nsP3 macrodomain, postulating them as a potential target of action for the CHIKV control.

Disparities in Compliance with Colorectal Cancer Screening: Evidence from Two US National Surveys.

OBJECTIVE: Colorectal cancer (CRC) is the most preventable cancer if adherence to its screening guidelines through compliance with physician recommendations are met. Lack of access to care is the most significant barrier which was decreased by the Affordable Care Act (ACA), that may influence healthcare behaviors/practices. The aim of this study was to determine the factors affecting compliance with recommendations for CRC screening between two US National Health Interview Surveys (NHIS) in 2010 and 2015. METHODS: We used individual data of adults aged ≥50 years from the Cancer Module of NHIS that repeats every-5-years. Multiple logistic regression analyses were employed to identify the compliance associated factors and their changes after five years. RESULTS: We included final data of 1,553 and 2259 and individual from 2010 and 2015, respectively. Overall, compliance to physician recommendations for colorectal cancer was 85.70% in 2010 and 81.54%. Men compiled more in 2010 than women which was reversed in 2015. The multivariable-adjusted odds of compliance were increased with age; lower for female [Odds ratio (OR)= 0.45 Confidence Interval (CI 95% 0.27, 0.75), having a family history of CRC [OR=3.05 CI:1.02, 9.05], having insurance [OR 3.58 CI:1.4, 9.12], and Odds increased with the number of doctor visit in 2010. However, in 2015 the odds were substantially increased with the increasing age, reversed odds for female [OR= 3.49 CI: 1.67, 7.29)], increased for non-Hispanic Blacks [OR= 4.87 CI: 2.05, 11.55] and lower for Asian [OR=0.33 CI:0.15, 0.74], higher for family history of colorectal cancer [OR=3.31 CI:1.92, 5.69]. Although insurance coverage and the number of doctor visits were significant predictors of compliance in 2010, those became non-significant in 2015. CONCLUSIONS: Compliance disparities by gender and access to healthcare either reduced in strength or reversed between 2010 and 2015. The non-Hispanic Black significantly higher in compliance than other race-ethnicities in 2015.

Cervical cancer screening programme attendance and compliance predictors regarding Colombia's Amazon region.

BACKGROUND: Cervical cancer (CC) promotion and prevention (P&P) programmes' challenge lies in guaranteeing that follow-up strategies have a real impact on reducing CC-related mortality rates. CC P&P programme compliance and coverage rates are relevant indicators for evaluating their success and good performance; however, such indicators' frequency rates are considerably lower among women living in rural and border areas. This study was aimed at identifying factors associated with CC screening programme attendance for women living in Colombia's Amazon region. METHODS: This study (qualitative and quantitative phases) was carried out between September 2015 and November 2016; women residing in the border towns of Leticia and Puerto Nariño participated in it. The first phase (qualitative) involved interviews and focus group discussions; this led to establishing factors related to CC P&P programme attendance which were used in the quantitative phase for designing a survey for determining the strength of association in a logistic regression model. The terms attendance and compliance were considered to apply to women who had followed the 1-1-3 scheme throughout their lives, i.e. a cytology examination every 3 years after receiving two consecutive negative annual cytology results. RESULTS: Inclusion criteria were met by 309 women (≥18-year-olds having an active sexual life, having resided in the target community for at least one year); 15.2% had suitable P&P programme follow-up. Screening programme attendance was positively associated with first intercourse after becoming 20 years-old (aOR: 3.87; 1.03-9.50 95%CI; p = 0.045), frequent contraceptive use (aOR: 3.11; 1.16-8.33 95%CI; p = 0.023), awareness of the age to participate in P&P programmes (aOR: 2.69; 1.08-6.68 95%CI; p = 0.032), awareness of cytology's usefulness in identifying cervical abnormalities (aOR: 2.43; 1.02-5.77 95%CI; p = 0.043) and considering cytology important (aOR: 2.64; 1.12-6.19 95%CI; p = 0.025). Women living in rural areas had a lower probability (aOR 0.43: 0.24-0.79 95%CI; p = 0.006) of adhering to CC P&P programmes. CONCLUSIONS: This study's findings suggested the need for including novel strategies in screening programmes which will promote CC P&P activities going beyond hospital outpatient attendance to reach the most remote or widely scattered communities, having the same guarantees regarding access, opportunity and quality. Including education-related activities and stimulating the population's awareness regarding knowledge about CC prevention could be one of the main tools for furthering the impact of attendance at and compliance with P&P programmes.

Minireview: Epidemiological impact of arboviral diseases in Latin American countries, arbovirus-vector interactions and control strategies.

Mosquitoes are the most crucial insects in public health due to their vector capacity and competence to transmit pathogens, including arboviruses, bacterias and parasites. Re-emerging and emerging arboviral diseases, such as yellow fever virus (YFV), dengue virus (DENV), zika virus (ZIKV), and chikungunya virus (CHIKV), constitute one of the most critical health public concerns in Latin America. These diseases present a significant incidence within the human settlements increasing morbidity and mortality events. Likewise, among the different genus of mosquito vectors of arboviruses, those of the most significant medical importance corresponds to Aedes and Culex. In Latin America, the mosquito vector species of YFV, DENV, ZIKV, and CHIKV are mainly Aedes aegypti and Ae. Albopictus. Ae. aegypti is recognized as the primary vector in urban environments, whereas Ae. albopictus, recently introduced in the Americas, is more prone to rural settings. This minireview focuses on what is known about the epidemiological impact of mosquito-borne diseases in Latin American countries, with particular emphasis on YFV, DENV, ZIKV and CHIKV, vector mosquitoes, geographic distribution, and vector-arbovirus interactions. Besides, it was analyzed how climate change and social factors have influenced the spread of arboviruses and the control strategies developed against mosquitoes in this continent.

Inverse Molecular Docking Study of NS3-Helicase and NS5-RNA Polymerase of Zika Virus as Possible Therapeutic Targets of Ligands Derived from Marcetia taxifolia and Its Implications to Dengue Virus.

Dengue and Zika are two mosquito-borne diseases of great impact on public health around the world in tropical and subtropical countries. DENV and ZIKV belong to the Flaviviridae family and the Flavivirus genus. Currently, there are no effective therapeutic agents to treat or prevent these pathologies. The main objective of this work was to evaluate potential inhibitors from active compounds obtained from Marcetia taxifolia by performing inverse molecular docking on ZIKV-NS3-helicase and ZIKV-NS5-RNA polymerase as targets. This computational strategy is based on renormalizing the binding scores of the compounds to these two proteins, allowing a direct comparison of the results across the proteins. The crystallographic structures of the ZIKV-NS3-helicase and ZIKV-NS5-RNA-polymerase proteins share a great similarity with DENV homologous proteins. The P-loop active site of the crystallographic structure of ZIKV-NS3-helicase presents a high percentage of homology with the four dengue serotypes. It was found that most ligands of the active compounds (5,3'-dihydroxy-3,6,7,8,4'-pentamethoxyflavone (5DP); 5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone (5HH); myricetin-3-O-rhamnoside (M3OR)) from Marcetia taxifolia had a better affinity for ZIKV-NS3-helicase than for ZIKV-NS5-RNA polymerase, as indicated by the negative multiple active site correction (MASC) score, except for M3RG that showed a higher affinity for ZIKV-NS5-RNA polymerase. On the other hand, the AutoDock Vina scores showed that M3OR had the highest score value (-9.60 kcal/mol) and the highest normalized score (1.13) against ZIKV-NS3-helicase. These results in silico demonstrated that the nonstructural proteins NS3-helicase and NS5-RNA polymerase, which share similar molecular structures between the selected viruses, could become therapeutic targets for some bioactive compounds derived from Marcetia taxifolia.

Endovascular Therapy in Mild Ischemic Strokes Presenting Under 6 hours: An International Survey.

BACKGROUND: Endovascular therapy (EVT) for patients with mild ischemic stroke (NIHSS ≤5) and visible intracranial occlusion remains controversial, including within 6 hours of symptom onset. We conducted a survey to evaluate global practice patterns of EVT in this population. METHODS: Vascular stroke clinicians and neurointerventionalists were invited to participate through professional stroke listservs. The survey consisted of six clinical vignettes of mild stroke patients with intracranial occlusion. Cases varied by NIHSS, neurological symptoms and occlusion site. All had the same risk factors, time from symptom onset (5h) and unremarkable head CT. Advanced imaging data was available upon request. We explored independent case and responder specific factors associated with advanced imaging request and EVT decision. RESULTS: A total of 482/492 responders had analyzable data ([median age 44 (IQR 11.25)], 22.7% women, 77% attending, 22% interventionalist). Participants were from USA (45%), Europe (32%), Australia (12%), Canada (6%), and Latin America (5%). EVT was offered in 48% (84% M1, 29% M2 and 19% A2) and decision was made without advanced imaging in 66% of cases. In multivariable analysis, proximal occlusion (M1 vs. M2 or A2, p<0.001), higher NIHSS (p<0.001) and fellow level training (vs. attending; p=0.001) were positive predictors of EVT. Distal occlusions (M2 and A2) and higher age of responders were independently associated with increased advanced imaging requests. Compared to US and Australian responders, Canadians were less likely to offer EVT, while those in Europe and Latin America were more likely (p<0.05). CONCLUSIONS: Treatment patterns of EVT in mild stroke vary globally. Our data suggest wide equipoise exists in current treatment of this important subset of mild stroke.

Molecular characteristics and replication mechanism of dengue, zika and chikungunya arboviruses, and their treatments with natural extracts from plants: An updated review.

Viruses transmitted by arthropods (arboviruses) are the etiological agents of several human diseases with worldwide distribution; including dengue (DENV), zika (ZIKV), yellow fever (YFV), and chikungunya (CHIKV) viruses. These viruses are especially important in tropical and subtropical regions; where, ZIKV and CHIKV are involved in epidemics worldwide, while the DENV remains as the biggest problem in public health. Factors, such as, environmental conditions promote the distribution of vectors, deficiencies in health services, and lack of effective vaccines, guarantee the presence of these vector-borne diseases. Treatment against these viral diseases is only palliative since available therapies formulated lack to demonstrate specific antiviral activity and vaccine candidates fail to demonstrate enough effectiveness. The use of natural products, as therapeutic tools, is an ancestral practice in different cultures. According to WHO 80 % of the population of some countries from Africa and Asia depend on the use of traditional medicines to deal with some diseases. Molecular characteristics of these viruses are important in determining its cellular pathogenesis, emergence, and dispersion mechanisms, as well as for the development of new antivirals and vaccines to control strategies. In this review, we summarize the current knowledge of the molecular structure and replication mechanisms of selected arboviruses, as well as their mechanism of entry into host cells, and a brief overview about the potential targets accessed to inhibit these viruses in vitro and a summary about their treatment with natural extracts from plants.

Visualization of Focal Thinning of the Ganglion Cell-Inner Plexiform Layer in Patients with Mild Cognitive Impairment and Alzheimer's Disease.

BACKGROUND: A detailed analysis of the tomographic thickness of intraretinal layers may provide more information on neurodegeneration in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). OBJECTIVE: The goal was to analyze tomographic thickness patterns of intraretinal layers in patients with AD andMCI. METHOD: Forty-nine patients (25 AD and 24 MCI) and 21 cognitively normal (CN) controls were imaged using ultra-high-resolution optical coherence tomography to obtain volumetric data centered on the fovea. The segmented intraretinal layers were retinal nerve fiber layer (RNFL), ganglion cell- inner plexiform layer (GCIPL), inner nuclear layer (INL), outer nuclear layer (ONL), outer plexiform layer (OPL), and retinal photoreceptor (PR), in addition to the total retinal thickness(TRT). RESULTS: The thickness differences were negative (thinning) mainly in TRT, RNFL, and GCIPL in both AD and MCI groups in comparison to CN, while the thickness differences were positive (thickening) mainly in ONL and PR in AD. GCIPL of AD and MCI was thinner in superior, nasal superior, and temporal superior quadrants, compared to CN (p < 0.05). GCIPL of the inner superior, inner nasal superior, inner temporal superior, and outer nasal superior sectors was significantly thinner in AD than CN (p < 0.05). GCIPL of the outer superior, inner temporal superior, outer nasal, and temporal superior sectors was significantly thinner in MCI than CN (p < 0.05). CONCLUSION: Focal thinning of the GCIPL was visualized and quantified by detailed partitions in AD and MCI, which provides specific information about neurodegeneration in MCI and AD.

Evaluation of clinical and biological prognostic factors in relapsed or refractory diffuse large B-cell lymphoma patients after previous treatment with rituximab and chemotherapy: results of the PRO-R-IPI study.

INTRODUCTION: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, showing a highly variable outcome. In patients with DLBCL relapsed/refractory to first-line treatment with rituximab the usefulness of the revised International Prognostic Index (R-IPI) as a prognostic tool remains unexplored. Some biological parameters (B-cell lymphoma 6 [Bcl-6], Bcl-2, p53, and multiple myeloma 1 [MUM1]) and blood populations (lymphocyte and monocyte counts) have been described as International Prognostic Index-independent prognostic factors. The objective was to evaluate the R-IPI to predict the outcome of DLBCL patients at the time of relapse after a front-line treatment with chemotherapy and rituximab and to establish in this population the relationship between biological parameters and outcome. PATIENTS AND METHODS: We included patients with refractory/relapsed DLBCL after first-line treatment with rituximab-containing regimens; patients must have already finished a rescue treatment also including rituximab. Immunohistochemical assessment of Bcl-2, Bcl-6, p53, and MUM1 expression were undertaken in available biopsies. R-IPI factors were identified from the clinical data at diagnosis and at relapse. Response was assessed using National Cancer Institute-sponsored Working Group guidelines. RESULTS: R-IPI prognosis at relapse was not significantly associated with overall response rate (ORR) after Rituximab-chemotherapy rescue therapy. None of the immunohistochemical parameters analyzed correlated with rescue therapy results. In contrast, patients with absolute lymphocyte count (ALC) ≥ 1 × 10(9)/L at relapse were more likely to respond than patients with ALC < 1 × 10(9)/L (P = .05). CONCLUSION: The R-IPI score calculated at relapse could not predict the ORR to second-line treatment. Lymphopenia is a simple and useful predictor for outcome in relapsed/refractory DLBCL and the only prognostic factor that in our hands could predict the overall response to a second-line treatment with rituximab and chemotherapy.

Normalización de un método inmunoquímico para detectar Papilomavirus humano tipo 16 en lesiones cérvico-uterinas / Standardization of immunochemical method for detection of type 16 human papilomavirus in cervix uterine lesions

Introducción: la infección por Papilomavirus Humano (PVH) es la condición necesaria para la aparición y desarrollo del cáncer cérvico-uterino. Los genotipos de alto riesgo oncogénico son los causantes de este tipo de neoplasia y dentro de ellos el más frecuente es el PVH 16, que se encuentra aproximadamente en el 60 % de los casos. Los métodos de diagnóstico comerciales resultan costosos para países con escasos recursos económicos, lo que sugiere la búsqueda de alternativas empleando protocolos sencillos y baratos. Objetivos: normalizar un método inmunoquímico para la detección del antígeno L1 de PVH tipo 16 en muestras cérvico-uterinas de pacientes con lesiones intraepiteliales escamosas y determinar la coincidencia entre el método normalizado y la Reacción en Cadena de la Polimerasa en Tiempo Real (RCP-TR), como técnica de referencia, para estimar la utilidad de dicho método en el diagnóstico de la infección por este genotipo viral. Métodos: se compararon tres procedimientos de inmunotinción (Indirecto de inmunoperoxidasa en dos pasos, Estreptavidina-Biotina y Amplificación por polímero) respecto a sensibilidad analítica, tinción inespecífica de fondo y tiempo de terminación, para la detección de la proteína L1 de PVH 16 en líneas celulares derivadas de carcinomas cervicales humanos y en muestras cérvico-uterinas utilizadas como controles. El protocolo normalizado se aplicó a muestras cérvico-uterinas de mujeres entre 30 y 59 años, 82 con lesiones intraepiteliales cervicales y 10 sin antecedentes de alteraciones citológicas, a las que además se les determinó PVH 16 mediante RCP-TR. Resultados: el procedimiento de Estreptavidina-Biotina resultó el más sensible y específico. La coincidencia entre el método inmunoquímico y la RCP-TR fue de un 98,6 por ciento, la sensibilidad fue de un 98,57 por ciento y la especificidad de un 91,67 por ciento, con valores predictivos negativo y positivo por encima del 90 por ciento. Conclusiones: se demostró la validez del método inmunoquímico como prueba confirmatoria de la infección por PVH 16. Dicho método probó ser sensible, sencillo y no requiere de una compleja infraestructura para detectar PVH 16 en muestras cervicales. Además, esta técnica permite obtener información rápidamente y evita el uso de métodos invasivos(AU)

Introduction: Human Papillomavirus (HPV) infection is the necessary condition for the occurernce and development of cervical cancer. The high oncogenic risk genotypes are the responsible for this type of neoplasia and the most frequent is HPV 16 that affects roughly 60 percent of cases. Commercial kits for HPV detection are expensive for resource-poor countries, which suggests the search for alternative throguh non-expensive simple protocoles. Objectives: to standardize an immunochemical method for the detection of HPV 16 L1 antigen in cervical samples of patients with squamous intraepithelial lesions and to determine the diagnostic coincidence between the immunochemical method and the real-time polymerase chain reaction to estimate the usefulness of this method for the detection of cervical infection with this viral genotype. Methods: three immunostaining methods (Two-Step Indirect Immunoperoxidase, Labelled Streptavidin-Biotin and Enhanced Polymer) were compared in terms of analytical sensitivity, nonspecific background staining and time of completion, for the detection of protein L1 of HPV-16 in a cell line derived from human cervical carcinoma and clinical samples from uterine cervix. The optimized protocol was applied to 82 cervical samples from women aged 30-59 years with squamous intraepithelial lesions and to 10 samples of sexually active women without previous signals of positive cytology. The presence of type 16 HPV was also detected with the aid of RT-PCR. Results: the Streptavidin-Biotin system was the most sensitive and specific. The diagnostic agreement between the immunochemical method and the real-time polymerase chain reaction reached 98.6 percent, sensitivity was 98.57 percent and specificity was 91.67 %, with positive and negative predictive values above 90 percent. Conclusions: the validity of the immunochemical method as a confirmatory test for infection by HPV-16 has been demonstrated. The normalized immunochemical method proved to be a sensitive, simple, relatively fast method to detect HPV from clinical samples of cervical cells. Furthermore, this method provides information quickly, avoiding the use of invasive methods in patients(AU)

Normalización de un método inmunoquímico para detectar Papilomavirus humano tipo 16 en lesiones cérvico-uterinas / Standardization of immunochemical method for detection of type 16 human papilomavirus in cervix uterine lesions

Introducción: la infección por Papilomavirus Humano (PVH) es la condición necesaria para la aparición y desarrollo del cáncer cérvico-uterino. Los genotipos de alto riesgo oncogénico son los causantes de este tipo de neoplasia y dentro de ellos el más frecuente es el PVH 16, que se encuentra aproximadamente en el 60 por ciento de los casos. Los métodos de diagnóstico comerciales resultan costosos para países con escasos recursos económicos, lo que sugiere la búsqueda de alternativas empleando protocolos sencillos y baratos. Objetivos: normalizar un método inmunoquímico para la detección del antígeno L1 de PVH tipo 16 en muestras cérvico-uterinas de pacientes con lesiones intraepiteliales escamosas y determinar la coincidencia entre el método normalizado y la Reacción en Cadena de la Polimerasa en Tiempo Real (RCP-TR), como técnica de referencia, para estimar la utilidad de dicho método en el diagnóstico de la infección por este genotipo viral. Métodos: se compararon tres procedimientos de inmunotinción (Indirecto de inmunoperoxidasa en dos pasos, Estreptavidina-Biotina y Amplificación por polímero) respecto a sensibilidad analítica, tinción inespecífica de fondo y tiempo de terminación, para la detección de la proteína L1 de PVH 16 en líneas celulares derivadas de carcinomas cervicales humanos y en muestras cérvico-uterinas utilizadas como controles. El protocolo normalizado se aplicó a muestras cérvico-uterinas de mujeres entre 30 y 59 años, 82 con lesiones intraepiteliales cervicales y 10 sin antecedentes de alteraciones citológicas, a las que además se les determinó PVH 16 mediante RCP-TR. Resultados: el procedimiento de Estreptavidina-Biotina resultó el más sensible y específico...

Introduction: Human Papillomavirus (HPV) infection is the necessary condition for the occurernce and development of cervical cancer. The high oncogenic risk genotypes are the responsible for this type of neoplasia and the most frequent is HPV 16 that affects roughly 60 percent of cases. Commercial kits for HPV detection are expensive for resource-poor countries, which suggests the search for alternative throguh non-expensive simple protocoles. Objectives: to standardize an immunochemical method for the detection of HPV 16 L1 antigen in cervical samples of patients with squamous intraepithelial lesions and to determine the diagnostic coincidence between the immunochemical method and the real-time polymerase chain reaction to estimate the usefulness of this method for the detection of cervical infection with this viral genotype. Methods: three immunostaining methods (Two-Step Indirect Immunoperoxidase, Labelled Streptavidin-Biotin and Enhanced Polymer) were compared in terms of analytical sensitivity, nonspecific background staining and time of completion, for the detection of protein L1 of HPV-16 in a cell line derived from human cervical carcinoma and clinical samples from uterine cervix. The optimized protocol was applied to 82 cervical samples from women aged 30-59 years with squamous intraepithelial lesions and to 10 samples of sexually active women without previous signals of positive cytology. The presence of type 16 HPV was also detected with the aid of RT-PCR. Results: the Streptavidin-Biotin system was the most sensitive and specific...

HIV-1 and GBV-C co-infection in Venezuela.

INTRODUCTION: Co-infection with GB virus C (GBV-C) in patients infected with human immunodeficiency virus 1 (HIV-1) has been associated with prolonged survival. The aim of this study was to evaluate the prevalence of GBV-C infection among HIV-1-infected patients in Venezuela, and to determine the effects of the co-infection on the levels of relevant cytokines. METHODOLOGY: Plasma samples were collected from 270 HIV-1-seronegative and 255 HIV-1-seropositive individuals. GBV-C infection was determined by RT-PCR of the NS5 region and genotyped by sequence analysis of the 5´UTR region. HIV-1 strains were characterized by sequence analysis of pol, vif, env, and nef genes. Selected cytokines were evaluated by ELISA. RESULTS: Ninety-seven of 525 (18.5%) plasma samples tested positive for GBV-C RNA. A significantly higher prevalence of GBV-C was found among HIV-1 patients compared to HIV-1-seronegative individuals (67/255, 26% versus 30/270, 11%; p < 0.001). Statistical difference was observed in the viral load between HIV-1+GBV-C+ and HIV-1+GBV-C- (p = 0.014), although no differences in CD4+ cell counts were found between both groups. TNFα concentration was higher in HIV-1+GBV-C- than in HIV-1+GBV-C+ patients (25.9 pg/mL versus 17.3 pg/mL; p = 0.02); RANTES expression levels were more variable in GBV-C co-infected patients and more frequently elevated in HIV-1 mono-infected patients compared to patients co-infected with GBV-C. CONCLUSIONS: The previously observed beneficial effect of co-infection with HIV-1 and GBV-C on disease progression is complex and might be due in part to a change in the cytokine environment. More studies are required to understand the interaction between both viruses.

Deletion, insertion and stop codon mutations in vif genes of HIV-1 infecting slow progressor patients.

BACKGROUND: Variable progression towards AIDS has been described and has been related to viral and host factors. Around 10% of the HIV-1 infected patients are slow progressors (SP), not presenting with AIDS disease signs even after more than 10 years of infection. Viral gene defects have been associated with the disease progression but more studies are still needed. METHODOLOGY: The sequence of vif and nef were analyzed for HIV-1 infecting 14 SP and 46 normal progressors (NP) patients. RESULTS: Co-circulation of a strain carrying vif deleted gene with the wild type strain was detected in an SP patient with more than 10 years of infection. Other mutations (insertion in aa 63 in one strain, two premature stop codons in another one) were found in viruses infecting two other patients. Except for the SP8 strain, which exhibited a premature stop codon in nef, no gross deletions or insertions were observed in nef genes of both NPs and SPs strains analyzed. CONCLUSIONS: Different kind of mutation: deletion, insertion and stop codon, were detected in 3/14 samples from SP, with co-circulation of a 195 bp vif deletion virus with a wild type in one of these patients. Although vif defects do not seem to be a frequent feature in SPs, this study illustrates the importance of analysing this gene, in addition to the multiple factors associated with the long-term non progression to AIDS.