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1.
BMC Infect Dis ; 19(1): 632, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31315573

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) testing in oral fluid samples may provide advantages in diagnosis, screening or prevalence studies, especially among individuals with venous access difficulties. This study aims to optimize one commercially available assay for detecting total anti-HBc marker in oral fluid samples and to evaluate its utility under real life conditions in different settings for the purposes of prevalence and diagnostic studies. METHODS: Oral fluid was collected using a Salivette device and some parameters were initially evaluated: type of elution buffer and sample volume. Thereafter, the utility of oral fluid samples for detection of anti-HBc was evaluated in real life conditions in which, 1296 individuals gave serum and oral fluid samples. All serum samples were submitted to commercial EIAs to detect total anti-HBc, according to the manufacturer's instructions and oral fluid samples according to previous optimization. RESULTS: In optimization evaluation, PBS/BSA 0.5% and 100 µL of oral fluid (volume was two-fold increased compared to serum in EIA) were chosen as transport buffer and sample volume. In the field study, anti-HBc was detected in 211 out of 1296 serum samples giving overall oral fluid sensitivity of 52.6% and specificity of 96%. Concordance was higher in ambulatory setting (67.7) compared to general population (31.8). Mean ± standard deviation values of optical density/cutoff (OD/CO) in serum samples were higher in false-negative oral fluid samples than those seen in true positive samples. Sensitivity was higher in those presenting active infection compared to anti-HBc isolate and past infection. Sensitivity also increased in the ambulatory group when HCV individuals were excluded. CONCLUSIONS: It was possible to optimize a commercial EIA for detecting anti-HBc in oral fluid samples and where the highest concordance was found in ambulatory settings and among individuals with active infection.


Asunto(s)
Anticuerpos contra la Hepatitis B/análisis , Hepatitis B/diagnóstico , Técnicas para Inmunoenzimas/métodos , Saliva/virología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
2.
J Med Virol ; 90(8): 1358-1363, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29663457

RESUMEN

In Brazil, the Amazon Basin is endemic for hepatitis D virus (HDV) infection; however, studies in other regions of the country are scarce. This study aims to map the seroepidemiological situation of anti-Delta antibodies in chronic hepatitis B carriers in all five Brazilian geographic regions. Serum samples from 1240 HBsAg positive individuals (55.4% men; mean age 43.1 ± 13.4 years) from 24 of 26 Brazilian states were tested for the presence of anti-Delta antibodies using a commercial immunoassay. Anti-Delta antibodies were detected in 40 samples (3.2%; 52.5% female; mean age of 38.1 ± 13.8 years). Age less than 20 years was significantly associated with anti-HDV positivity (P < 0.001). The distribution of anti-Delta differed markedly in the diverse regions of the country. The highest prevalence of anti-HDV was found in the North (8.5%; P < 0.001), followed by Central West (2.5%), Southeast (1.7%), Northeast (0.8%), and South (0.0%). Anti-Delta antibodies were detected in 12 states, but more than 60% of the positive cases were observed in two states, Amazonas and Acre, located in the western portion of the Amazon region. The overall HDV prevalence of 3.2% emphasizes that HDV is far from being a disease under control in Brazil. Despite the low HDV prevalence in non-endemic regions, this infection persists as a major concern in two states (Acre and Amazonas) in the north of the country, indicating that a continuous epidemiological surveillance program should be implemented in all Brazilian regions.


Asunto(s)
Anticuerpos Antihepatitis/sangre , Hepatitis B Crónica/complicaciones , Hepatitis D/epidemiología , Virus de la Hepatitis Delta/inmunología , Topografía Médica , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Niño , Preescolar , Femenino , Humanos , Inmunoensayo , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos , Adulto Joven
3.
J Med Virol ; 90(12): 1863-1867, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30085359

RESUMEN

This study aims to evaluate the utility of an optimized enzyme immunoassay (EIA) to detect and quantify antibodies against hepatitis B surface antibody (anti-HBs) in dried blood spots (DBSs) within the context of human immunodeficiency virus (HIV) status. Serum and DBS samples were obtained from 56 HIV+ and 99 HIV- patients and subjected to EIA for the detection of anti-HBs, where sample volume and cut off value were modified for DBS testing. Sensitivities of anti-HBs detection in DBS were 79.8% and 76.8% in HIV- and HIV+ subjects, respectively. Concordant results for anti-HBs in serum and DBS presented high mean CD8 cell counts, HIV viral load and optical density (OD) values of anti-HBs. Anti-HBs titers were significantly higher in serum, whether or not anti-HBs titers were detected in DBS. It was possible to detect anti-HBs in DBS as low as 17.4 and 27.3 IU/mL among HIV+ and HIV- subjects, respectively. In conclusion, DBS can be used to detect and quantify anti-HBs in HIV-infected individuals, which could increase access to diagnosis and vaccination.


Asunto(s)
Desecación , Infecciones por VIH , Anticuerpos contra la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B/inmunología , Tamizaje Masivo/métodos , Manejo de Especímenes/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Antígenos de Superficie de la Hepatitis B/inmunología , Humanos , Técnicas para Inmunoenzimas/métodos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto Joven
4.
BMC Infect Dis ; 18(1): 411, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30126364

RESUMEN

BACKGROUND: This study was conducted to determine the prevalence of HBV, HCV, and HDV in urban populations and Amerindians living in the state of Tocantins (Eastern Amazon). METHODS: A total of 948 individuals were recruited in Tocantinopolis city (Tocantins state) of whom 603 were Amerindians (from 6 tribes) and 345 were non-Amerindians (6 urban areas of Tocantinópolis city). Anti-HCV, HBsAg, anti-HBc, anti-HBs, anti-HBc IgM, anti-HBe, HBeAg, and anti-delta antibodies were determined using enzyme immunoassay. RESULTS: HBV cleared infection (both anti-HBc/anti-HBs+), chronic inactive/immune controlled HBV infection (anti-HBc + only), previous HBV vaccination (anti-HBs + only), active HBV infection (HBsAg+), individuals susceptible to HBV, and anti-HCV reactivity were found in 12.9, 1.8, 27.2, 0.5, 57.7, 1.2% in Amerindians and 12.1, 2.0, 37.1, 0.3, 55.4, 0.3% in non-Amerindians respectively. Out of 139 anti-HBc reactive individuals, 70 were anti-HBe reactive and none presented HBeAg or anti-HBc IgM. Anti-HBc prevalence was associated to older age (p < 0.0001). Overall anti-Delta prevalence was 0.3% and regarding anti-HBc reactive individuals, anti-delta prevalence was 3.4 and 0% in Amerindians and non-Amerindians respectively. CONCLUSIONS: Overall low prevalence of HBV and HCV infection was found in the populations studied, but high HBV and HCV prevalence was observed in Amerindians compared to non-Amerindians suggesting that these individuals have a higher likelihood of acquiring to these infections. Anti-delta antibodies were found among Amerindians from Eastern Amazon suggesting a risk for this population. Of note is that nearly half of Amerindians had no anti-HBs, indicating a need for HBV vaccination campaigns in this population.


Asunto(s)
Hepatitis B/epidemiología , Hepatitis C/epidemiología , Hepatitis D/epidemiología , Indígenas Norteamericanos/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Hepatitis B/sangre , Anticuerpos contra la Hepatitis B/análisis , Anticuerpos contra la Hepatitis B/sangre , Hepatitis C/sangre , Anticuerpos contra la Hepatitis C/análisis , Anticuerpos contra la Hepatitis C/sangre , Hepatitis D/sangre , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Prevalencia , Ríos , Adulto Joven
5.
Mem Inst Oswaldo Cruz ; 113(1): 62-65, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29211108

RESUMEN

In occult hepatitis B infection (OBI), hepatitis B virus DNA (HBV DNA) can be detected in serum samples; however, oral fluid collection for detection of HBV DNA has not yet been explored, despite the availability of collection devices. Serum and oral fluid samples from 45 hepatitis B core antibody (anti-HBc)-positive patients were collected for the amplification of the HBV polymerase gene. HBV DNA was detected in five serum and four oral fluid samples (the detection limit for oral fluid was 1.656 log IU/mL in paired serum). In conclusion, simple methodologies of sample collection and in-house polymerase chain reaction (PCR) allowed detection of HBV DNA, and these could be used to improve the diagnosis of OBI, especially in locations with limited resources.


Asunto(s)
ADN Viral/análisis , Anticuerpos contra la Hepatitis B/análisis , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Hepatitis B/diagnóstico , Saliva/virología , Adulto , Anciano , ADN Viral/sangre , Femenino , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Carga Viral
6.
J Immunoassay Immunochem ; 39(2): 228-233, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29733758

RESUMEN

Dried blood spots (DBSs) could be an alternative to serum for hepatitis B virus (HBV) and hepatitis C virus (HCV) diagnosis. This study aims to evaluate two enzyme immunoassays (EIAs) for HBsAg and anti-HCV detection using DBS. Serum was tested using commercial EIA. DBS was tested using optimized EIA developed for serum and commercial EIA developed for DBS (Imunoscreen). Concordances between DBS and serum samples for both markers and EIAs were higher than 97%. Both EIAs demonstrated good performance for HBsAg and anti-HCV detection using DBS, and these methods could be used unchangeably increasing the access for HBV and HCV diagnosis.


Asunto(s)
Pruebas con Sangre Seca , Hepacivirus/aislamiento & purificación , Virus de la Hepatitis B/aislamiento & purificación , Técnicas para Inmunoenzimas/métodos , Humanos
7.
J Gen Virol ; 98(6): 1389-1398, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28631602

RESUMEN

The influence of hepatitis B virus (HBV) genotypes in the natural history of the disease and its response to antiviral treatment have been addressed in many studies. In Brazil, studies on HBV genotype circulation have been restricted to specific population groups and states. Here, we have conducted a nationwide multicentre study with an unprecedented sample size representing all Brazilian regions in an effort to better understand the viral variants of HBV circulating among chronic carriers. Seven HBV genotypes were found circulating in Brazil. Overall, HBV/A was the most prevalent, identified in 589 (58.7 %) samples, followed by HBV/D (23.4 %) and HBV/F (11.3 %). Genotypes E, G, C and B were found in a minor proportion. The distribution of the genotypes differed markedly from the north to the south of the country. While HBV/A was the most prevalent in the North (71.6 %) and Northeast (65.0 %) regions, HBV/D was found in 78.9 % of the specimens analysed in the South region. HBV/F was the second most prevalent genotype in the Northeast region (23.5 %). It was detected in low proportions (7 to 10 %) in the North, Central-West and Southeast regions, and in only one sample in the South region. HBV/E was detected in all regions except in the South, while monoinfection with HBV/G was found countrywide, with the exception of Central-West states. Our sampling covered 24 of the 26 Brazilian states and the Federal District and is the first report of genotype distribution in seven states. This nationwide study provides the most complete overview of HBV genotype distribution in Brazil to date and reflects the origin and plurality of the Brazilian population.


Asunto(s)
Genotipo , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B/epidemiología , Hepatitis B/virología , Filogeografía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Femenino , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
8.
J Med Virol ; 89(8): 1435-1441, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28165155

RESUMEN

The use of saliva and dried blood spots (DBS) could increase access to HCV diagnosis for high-risk populations, such as HIV-infected individuals, but the performance of these assays has not been well established in this group. This study aims to evaluate HIV status, particularly TCD4+ cell count and viral load, in the performance of anti-HCV testing using DBS and saliva. A total of 961 individuals classified as HCV+, HIV+, or HIV/HCV+, as well as negative controls, donated serum, DBS, and saliva samples for anti-HCV testing using a commercial enzyme immunoassay. Sample volume was modified for DBS and saliva, and an ROC curve was used for cut-off determination in saliva. Anti-HCV sensitivities were greater than 93% using DBS and saliva in the HCV+ group, while they were 83.3% and 95.6% for HCV/HIV+ individuals for DBS and saliva assays, respectively. Specificity varied from 91.7% to 100% using saliva and DBS in HIV monoinfected and control subjects. When only anti-HCV/HCV RNA+ serum samples, that is, true positives, were considered, the sensitivities were 98.3% and 100% for DBS and saliva, respectively, in the HCV+ group and 91.6% and 94.8% for DBS and saliva, respectively, in the HIV/HCV+ group. High absorbance values were observed among those presenting with HCV RNA in serum and low HIV viral load (less than 50 copies/mL). In conclusion, DBS and saliva samples could be used for anti-HCV detection, particularly to identify active HCV cases, but low sensitivity was observed for anti-HCV testing using DBS in the HIV/HCV+ group.


Asunto(s)
Sangre/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Infecciones por VIH/complicaciones , Anticuerpos contra la Hepatitis C/análisis , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/diagnóstico , Saliva/inmunología , Adulto , Anciano , Recuento de Linfocito CD4 , Desecación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Manejo de Especímenes/métodos , Encuestas y Cuestionarios , Carga Viral
9.
Dis Aquat Organ ; 123(2): 123-140, 2017 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-28262634

RESUMEN

The intracellular fish pathogen Francisella noatunensis remains an unsolved problem for aquaculture worldwide and an efficient vaccine is needed. In Francisella sp., IglC is an important virulence factor necessary for intracellular growth and escape from phagolysosomes. Deletion of the intracellular growth locus C (iglC) in Francisella sp. causes attenuation, but vaccine potential has only been attributed to ΔiglC from Francisella noatunensis ssp. orientalis, a warm-water fish pathogen. A ΔiglC mutant was constructed in the cold-water fish pathogen F. noatunensis ssp. noatunensis (Fnn), which causes francisellosis in Atlantic cod; the mutant was assessed in primary head kidney leucocytes from Atlantic cod. Fluorescence microscopy revealed reduced growth, while qPCR revealed an initial increase followed by a reduction in mutant genomes. Mutant-infected cod leucocytes presented higher interleukin 1 beta (il1ß) and interleukin 8 (il8) transcription than wild-type (WT)-infected cells. Two doses of mutant and WT were tested in an adult zebrafish model whereupon 3 × 109 CFU caused acute disease and 3 × 107 CFU caused low mortality regardless of strain. However, splenomegaly developed only in the WT-infected zebrafish. Immunization with 7 × 106 CFU of Fnn ΔiglC protected zebrafish against challenge with a lethal dose of Fnn WT, and bacterial load was minimized within 28 d. Immunized fish had lower interleukin 6 (il6) and il8 transcription in kidney and prolonged interferon-gamma (ifng) transcription in spleens after challenge compared with non-immunized fish. Our data suggest an immunogenic potential of Fnn ΔiglC and indicate important cytokines associated with francisellosis pathogenesis and protection.


Asunto(s)
Proteínas Bacterianas/metabolismo , Francisella/patogenicidad , Infecciones por Bacterias Gramnegativas/veterinaria , Pez Cebra , Animales , Proteínas Bacterianas/genética , Citocinas/genética , Citocinas/metabolismo , Francisella/clasificación , Francisella/genética , Gadiformes/fisiología , Eliminación de Gen , Regulación de la Expresión Génica/inmunología , Regulación de la Expresión Génica/fisiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/mortalidad , Riñón Cefálico/citología , Leucocitos/microbiología , Regulación hacia Arriba , Virulencia
10.
Mem Inst Oswaldo Cruz ; 112(7): 485-491, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28591309

RESUMEN

BACKGROUND: Many studies have identified mutations in the hepatitis B surface antigen (HBsAg) as important factors limiting the ability of commercial serological assays to detect this viral antigen. However, an association between mutations in the HBsAg gene and the occurrence of occult HBV infection (OBI) in patients has not been established. OBJECTIVES: To detect hepatitis B virus (HBV) DNA in patients with anti-HBc as a unique serological marker, a previously published, cost-effective TaqMan-based real-time polymerase chain reaction (PCR) test with minor groove binding probes was adapted for use in this study. The current study also aimed to investigate HBsAg mutations and genotypes of HBV in OBI at the Viral Hepatitis Ambulatory Clinic in Rio de Janeiro to determine any possible association. METHODS: Intra-assay and inter-assay reproducibility were determined, and the mean coefficient of variation values obtained were 2.07 and 3.5, respectively. Probit analysis indicated that the 95% detection level was 25 IU/mL. The prevalence of OBI was investigated in 35 serum samples with an 'anti-HBc alone' profile from individuals who attended our clinic between 2011 and 2013. FINDINGS: HBV DNA was detected in only one sample, resulting in an OBI rate of 2.9%. Nucleotide sequencing of the pre-S/S region was performed to genotype and analyse mutations within the HBsAg gene of this HBV DNA. The HBV in the OBI case was classified as sub-genotype A1, and a sequence analysis of the small S gene revealed 12 mutations in the major hydrophilic region compared to the consensus A1 sequence. Most of these mutations occurred in amino acid residues that have been reported as clinically relevant because they have been implicated in vaccine escape and/or inability to detect HBsAg by commercial serological assays. MAIN CONCLUSIONS: Our study suggests the importance of specific HBsAg mutations, different from those in D, B, and C genotypes, in sub-genotype A1 HBV associated with OBI.


Asunto(s)
ADN Viral/aislamiento & purificación , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B/diagnóstico , Brasil , ADN Viral/genética , Genotipo , Hepatitis B/virología , Humanos , Mutación , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Mem Inst Oswaldo Cruz ; 112(3): 209-213, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28146158

RESUMEN

Rapid tests (RTs) can be used as an alternative method for the conventional diagnosis of hepatitis B virus (HBV). This study aims to evaluate antibodies to HBsAg (anti-HBs) and antibodies to HBeAg (anti-HBe) RTs under different Brazilian settings. The following three groups were included: GI: viral hepatitis outpatient services; GII: low resource areas; and GIII: crack users and beauticians. Imuno-rápido anti-HBsAg™ and Imuno-rápido anti-HBeAg™ RTs were evaluated and showed specificities greater than 95% in all groups. The sensitivity values to anti-HBs were 50.38%, 51.05% and 46.73% and the sensitivity values to anti-HBe were 76.99%, 10.34% and 11.76% in the GI, GII and GIII groups, respectively. The assays had a low sensitivity and high specificity, which indicated their use for screening in regions endemic for HBV.


Asunto(s)
Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B/diagnóstico , Adulto , Humanos , Persona de Mediana Edad , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad
12.
Int J Mol Sci ; 18(7)2017 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-28753979

RESUMEN

The role of hepatitis C virus (HCV) in insulin resistance (IR) is not fully understood. The aim of this study was to determine the impact of amino acid (aa) substitutions in the core region of HCV according to IR and to identify clinical and laboratory associations. Ninety-two treatment-naive HCV patients were recruited to determine laboratory data and blood cell count. IR was determined using Homeostasis Model Assessment (HOMA) index where IR was defined as HOMA ≥2. HCV RNA load and genotype were determined by Abbott Real time HCV. HCV core region was determined by direct nucleotide sequencing. Bivariate analysis was conducted using HOMA IR ≥2 as a dependent factor. IR prevalence was 43.5% (n = 40), vitamin D sufficiency was found in 76.1% (n = 70) and 72.8% (n = 67) had advanced liver fibrosis. In the bivariate analyses, elevated values of γGT (p = 0.024) and fibrosis staging (p = 0.004) were associated with IR, but IR was not related to core mutations. The presence of glutamine in position 70 was associated with low vitamin D concentration (p = 0.005). In the multivariate analysis, no variable was independently associated with HOMA-IR. In conclusion, lack of association between IR and HCV core mutations in positions 70 and 91 suggests that genetic variability of this region has little impact on IR.


Asunto(s)
Sustitución de Aminoácidos , Hepacivirus/genética , Hepatitis C Crónica/sangre , Resistencia a la Insulina , Proteínas del Núcleo Viral/genética , Adulto , Anciano , Femenino , Estudios de Asociación Genética , Glutamina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ARN , Carga Viral
13.
J Antimicrob Chemother ; 70(3): 726-30, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25414201

RESUMEN

OBJECTIVES: Several promising NS5A protein inhibitors for hepatitis C virus (HCV) treatment, showing good antiviral activity, are currently being evaluated in clinical trials. However, viral breakthroughs associated with resistant variants have been observed, especially in patients infected with HCV-1a. We aimed to evaluate the occurrence of potential resistance mutations in the NS5A gene of HCV among Brazilian treatment-naive patients. METHODS: Direct sequencing of the HCV NS5A gene was performed in serum samples of 106 treatment-naive patients infected with subtypes 1a (n = 52) and 1b (n = 54). The sequence variability, signature patterns in amino acid sequences and variants associated with NS5A inhibitors were evaluated. RESULTS: The M28T and Y93H mutations were found in the subtype 1a sequences of two (3.85%) patients, and seven (13.46%) other patients presented the secondary mutation(s) H58P, E62D or H58P-E62D. For subtype 1b, the Y93H mutation was found in two (3.70%) patients and the substitutions R30Q, L31M, P58S and I280V were found in eight (14.81%) patients. Two distinct HCV-1a clades were distinguished by a phylogenetic analysis performed along with representative HCV-1a sequences and sequences containing HCV NS5A inhibitor resistance mutations retrieved from the Los Alamos database. All Brazilian sequences formed a large group of related sequences inside clade 1. It is noteworthy that 65.85% of sequences with substitution at sites 28, 30, 31 and 93 were found in clade 1. CONCLUSION: Brazilian HCV-1a sequences presented a peculiar pattern of amino acid composition, mutations and frequencies, which is distinct from other previously characterized sequences from other locations. The association of these findings with the outcome of treatment with NS5A inhibitors awaits further analysis.


Asunto(s)
Farmacorresistencia Viral , Hepacivirus/enzimología , Hepacivirus/genética , Hepatitis C Crónica/virología , Mutación Missense , Proteínas no Estructurales Virales/genética , Antivirales/uso terapéutico , Brasil , Ensayos Clínicos como Asunto , Análisis por Conglomerados , Genotipo , Hepacivirus/efectos de los fármacos , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Datos de Secuencia Molecular , Filogenia , Polimorfismo Genético , Análisis de Secuencia de ADN , Suero/virología
14.
Appl Environ Microbiol ; 82(5): 1586-1598, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26712555

RESUMEN

Francisella bacteria cause severe disease in both vertebrates and invertebrates and include one of the most infectious human pathogens. Mammalian cell lines have mainly been used to study the mechanisms by which Francisella manipulates its host to replicate within a large variety of hosts and cell types, including macrophages. Here, we describe the establishment of a genetically and biochemically tractable infection model: the amoeba Dictyostelium discoideum combined with the fish pathogen Francisella noatunensis subsp. noatunensis. Phagocytosed F. noatunensis subsp. noatunensis interacts with the endosomal pathway and escapes further phagosomal maturation by translocating into the host cell cytosol. F. noatunensis subsp. noatunensis lacking IglC, a known virulence determinant required for Francisella intracellular replication, follows the normal phagosomal maturation and does not grow in Dictyostelium. The attenuation of the F. noatunensis subsp. noatunensis ΔiglC mutant was confirmed in a zebrafish embryo model, where growth of F. noatunensis subsp. noatunensis ΔiglC was restricted. In Dictyostelium, F. noatunensis subsp. noatunensis interacts with the autophagic machinery. The intracellular bacteria colocalize with autophagic markers, and when autophagy is impaired (Dictyostelium Δatg1), F. noatunensis subsp. noatunensis accumulates within Dictyostelium cells. Altogether, the Dictyostelium-F. noatunensis subsp. noatunensis infection model recapitulates the course of infection described in other host systems. The genetic and biochemical tractability of the system allows new approaches to elucidate the dynamic interactions between pathogenic Francisella and its host organism.


Asunto(s)
Dictyostelium/microbiología , Francisella/crecimiento & desarrollo , Interacciones Huésped-Patógeno , Modelos Biológicos , Citosol/microbiología , Endosomas/microbiología , Fagocitosis
15.
Fish Shellfish Immunol ; 42(1): 50-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25449706

RESUMEN

Infection of fish with the facultative intracellular bacterium Francisella noatunensis remains an unresolved problem for aquaculture industry worldwide as it is difficult to vaccinate against without using live attenuated vaccines. Outer membrane vesicles (OMVs) are biological structures shed by Gram-negative bacteria in response to various environmental stimuli. OMVs have successfully been used to vaccinate against both intracellular and extracellular pathogens, due to an ability to stimulate innate, cell-mediated and humoral immune responses. We show by using atomic force and electron microscopy that the fish pathogenic bacterium F. noatunensis subspecies noatunensis (F.n.n.) shed OMVs both in vitro into culture medium and in vivo in a zebrafish infection model. The main protein constituents of the OMV are IglC, PdpD and PdpA, all known Francisella virulence factors, in addition to the outer membrane protein FopA and the chaperonin GroEL, as analyzed by mass spectrometry. The vesicles, when used as a vaccine, reduced proliferation of the bacterium and protected zebrafish when subsequently challenged with a high dose of F.n.n. without causing adverse effects for the host. Also granulomatous responses were reduced in F.n.n.-challenged zebrafish after OMV vaccination. Taken together, the data support the possible use of OMVs as vaccines against francisellosis in fish.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/farmacología , Francisella/inmunología , Infecciones por Bacterias Gramnegativas/prevención & control , Inmunidad Humoral/inmunología , Vesículas Transportadoras/inmunología , Vacunación/métodos , Animales , Cromatografía Liquida , Electroforesis en Gel de Poliacrilamida , Francisella/ultraestructura , Inmunidad Humoral/efectos de los fármacos , Estimación de Kaplan-Meier , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Espectrometría de Masas en Tándem , Vesículas Transportadoras/ultraestructura , Pez Cebra
16.
BMC Infect Dis ; 15: 548, 2015 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-26619906

RESUMEN

BACKGROUND: Rapid tests (RTs) might have several advantages over standard laboratory procedures, increasing access to diagnosis, especially among vulnerable populations and/or those living in remote areas. The aim of this study was to evaluate the performance of RTs for the detection of hepatitis B virus surface antigen (HBsAg) in samples from different populations/settings. METHODS: Three RTs for HBsAg detection (Vikia® HBsAg, HBsAg Teste Rápido®, and Imuno-Rápido HBsAg®) and different biological specimens (serum, whole blood, and saliva) were evaluated. Analyses comprised a reference panel and samples from field studies targeting suspected cases of hepatitis B virus (HBV) (G I), individuals living in deprived areas (G II), and highly vulnerable individuals (G III). Enzyme immunoassay (EIA) was defined as the gold standard in this study. Reproducibility, repeatability, and cross-reactivity with other infectious agents such as dengue, immunodeficiency (HIV), and hepatitis C (HCV) viruses and T. pallidum were determined. RESULTS: For the reference panel, the sensitivity and specificity of all HBsAg RTs were higher than 93.00 %. G I presented the highest kappa values for all rapid assays using sera samples. When using serum, the sensitivity values were higher than 93.40 for G I, 60.00 % for G II and 66.77 % for G III, and the specificity values were higher than 99.50 for GI, 97.20 for G II and 99.10 % for G III for all tests. For whole blood samples & the Vikia® HBsAg assay, the best performance was achieved for GIII (k = 79.75 %). For saliva samples, the Imuno-Rápido HBsAg® assay showed the highest concordance values with EIA for G I (40.68 %) and G II (32.20 %). The reproducibility and repeatability of all RTs for serum and saliva were excellent, and the concordance between HBsAg EIAs and RTs using samples reactive with other infectious agents varied from 70.10 % to 100.00 %. CONCLUSIONS: The overall performance of RTs for HBsAg in serum was high/moderately high for all groups, thereby promoting increased access to HBV diagnosis among vulnerable populations as well as samples from individuals in emergency settings or remote areas. Rapid tests for HBsAg using whole blood could be used in prevalence studies, though these assays should not be used for saliva samples.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B/diagnóstico , Técnicas para Inmunoenzimas/métodos , Adulto , Reacciones Cruzadas/inmunología , Femenino , Hepacivirus/inmunología , Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/inmunología , Hepatitis C/diagnóstico , Hepatitis C/virología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Ann Hepatol ; 14(4): 457-63, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26019031

RESUMEN

BACKGROUND: The relationship between 25-hydroxyvitamin D [25(OH)D] serum levels and response to antiviral therapy and laboratory data in HCV infection remains unclear. The aim of this study was to determine pre-treatment 25(OH)D serum level among HCV infected individuals and to evaluate the association between vitamin D status, virological response, and laboratory data. MATERIAL AND METHODS: Baseline serum 25(OH)D levels were measured in 237 chronic HCV infected patients (139 female, age 53.7 ± 11.2 years) using chemiluminescence immunoassay. Correlations between serum 25(OH)D levels, virological and laboratory data regarding HCV infection as well as sustained virological response (SVR) to antiviral therapy were evaluated. RESULTS: Mean serum values of 25(OH)D was 26.2 ± 12 ng/mL and prevalence of vitamin D deficiency (< 30 ng/mL) was 66.2%. Advanced age (> 55 years), high mean values of LDL, total cholesterol, HDL and low mean values of alkaline phosphatase and hemoglobin were statistically associated to vitamin D deficiency. Antiviral treatment was underwent by 133 HCV patients and 44.3% of them achieved SVR. Most of individuals that presented SVR also presented 25(OH)D level higher than 30ng/mL (55.9%). SVR was associated to low mean values of LDL, total cholesterol and platelets; high mean values of ALT, AST and low fibrosis grade. CONCLUSIONS: In conclusion, low vitamin D levels were observed among HCV infected patients and was associated to laboratory findings, however baseline 25(OH)D level is not independently associated with SVR.


Asunto(s)
Hepatitis C/sangre , Hepatitis C/epidemiología , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/epidemiología , Vitamina D/análogos & derivados , Adulto , Anciano , Antivirales/uso terapéutico , Biomarcadores/sangre , Brasil/epidemiología , Estudios Transversales , Femenino , Hepatitis C/diagnóstico , Hepatitis C/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Resultado del Tratamiento , Vitamina D/sangre , Deficiencia de Vitamina D/diagnóstico
18.
Mem Inst Oswaldo Cruz ; 110(5): 636-43, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26154744

RESUMEN

Inosine triphosphatase (ITPA) single nucleotide polymorphisms (SNPs) are strongly associated with protection against ribavirin (RBV)-induced anaemia in European, American and Asian patients; however, there is a paucity of data for Brazilian patients. The aim of this study was to evaluate the ITPA SNP (rs7270101/rs1127354) frequency in healthy and hepatitis C virus (HCV)-infected patients from Brazil and the association with the development of severe anaemia during antiviral therapy. ITPA SNPs were determined in 200 HCV infected patients and 100 healthy individuals by sequencing. Biochemical parameters and haemoglobin (Hb) levels were analysed in 97 patients who underwent antiviral therapy. A combination of AArs7270101+CCrs1127354 (100% ITPase activity) was observed in 236/300 individuals. Anaemia was observed in 87.5% and 86.2% of treated patients with AA (rs7270101) and CC genotypes (rs1127354), respectively. Men with AA (rs7270101) showed a considerable reduction in Hb at week 12 compared to those with AC/CC (p = 0.1475). In women, there was no influence of genotype (p = 0.5295). For rs1127354, men with the CC genotype also showed a sudden reduction in Hb compared to those with AC. Allelic distribution of rs7270101 and rs1127354 shows high rates of the genotypes AA and CC, respectively, suggesting that the study population had a great propensity for developing RBV-induced anaemia. A progressive Hb reduction during treatment was observed; however, this reduction was greater in men at week 12 than in women.


Asunto(s)
Anemia/inducido químicamente , Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Pirofosfatasas/genética , Ribavirina/uso terapéutico , Anemia/genética , Antivirales/efectos adversos , Brasil , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Genotipo , Hepatitis C Crónica/enzimología , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Ribavirina/efectos adversos , Inosina Trifosfatasa
19.
Infect Immun ; 82(6): 2180-94, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24614659

RESUMEN

Francisella spp. are facultative intracellular pathogens identified in increasingly diverse hosts, including mammals. F. noatunensis subsp. orientalis and F. noatunensis subsp. noatunensis infect fish inhabiting warm and cold waters, respectively, while F. tularensis subsp. novicida is highly infectious for mice and has been widely used as a model for the human pathogen F. tularensis. Here, we established zebrafish embryo infection models of fluorescently labeled F. noatunensis subsp. noatunensis, F. noatunensis subsp. orientalis, and F. tularensis subsp. novicida at 22, 28, and 32°C, respectively. All infections led to significant bacterial growth, as shown by reverse transcription-quantitative PCR (RT-qPCR), and to a robust proinflammatory immune response, dominated by increased transcription of tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß). F. noatunensis subsp. orientalis was the most virulent, F. noatunensis subsp. noatunensis caused chronic infection, and F. tularensis subsp. novicida showed moderate virulence and led to formation of relatively small granuloma-like structures. The use of transgenic zebrafish strains with enhanced green fluorescent protein (EGFP)-labeled immune cells revealed their detailed interactions with Francisella species. All three strains entered preferentially into macrophages, which eventually assembled into granuloma-like structures. Entry into neutrophils was also observed, though the efficiency of this event depended on the route of infection. The results demonstrate the usefulness of the zebrafish embryo model for studying infections caused by different Francisella species at a wide range of temperatures and highlight their interactions with immune cells.


Asunto(s)
Modelos Animales de Enfermedad , Enfermedades de los Peces/microbiología , Francisella , Infecciones por Bacterias Gramnegativas/microbiología , Temperatura , Pez Cebra/embriología , Animales , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/patología , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/patología
20.
J Med Virol ; 86(9): 1515-21, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24916521

RESUMEN

Beauty treatments, such as tattooing, piercing, manicures, pedicures, and barbershop shaving, can pose an important risk of virus transmission. This study was conducted to determine hepatitis A virus (HAV), hepatitis B virus (HBV), and hepatitis C virus (HCV) prevalence in a sample of beauticians from Rio de Janeiro (Southeast Brazil) and to assess the knowledge and attitudes of these professionals regarding viral hepatitis and their practices during their activities. One hundred nineteen beauticians were recruited in September 2010. Serum samples were tested for total anti-HAV, total anti-HBc, HBsAg, anti-HBs, and anti-HCV reactivity. A questionnaire was administered to identify socio-demographic risk factors and to determine knowledge and attitudes regarding viral hepatitis. Prevalence was 73.9% for total anti-HAV, 0% for HBsAg, 5.9% for anti-HBc, 23.6% for anti-HBs, and 0.8% for anti-HCV. Most professionals (81.5%) were well informed (4-7 correct answers) and reported the use of disposable sandpaper and nail sticks and sterilized pliers, but only 40% of them reported adequate processes of disinfection/sterilization. In conclusion, a high prevalence of HAV infection and a low prevalence of HBV and HCV infection were observed among beauticians. In addition, most of these individuals were not immune to HBV, indicating the need for vaccination campaigns targeting these professionals. Most of these professionals were well informed regarding viral hepatitis, although there was a gap in knowledge regarding disinfection and sterilization procedures. Public health prevention strategies should be adopted to improve education about disinfection/sterilization procedures for manicures and pedicures.


Asunto(s)
Hepatitis Viral Humana/epidemiología , Adulto , Industria de la Belleza/estadística & datos numéricos , Brasil/epidemiología , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Hepatitis Viral Humana/prevención & control , Hepatitis Viral Humana/transmisión , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Adulto Joven
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