Avaliação clínica e laboratorial hepática em indivíduos com insuficiência cardíaca congestiva

OBJETIVOS: Verificar o perfil de alterações clínicas e, principalmente, laboratoriais hepáticas observadas em pacientes de cada uma das classes de insuficiência cardíaca. MÉTODOS: Por meio de um estudo seccional, foram pesquisados os dados clínicos e laboratoriais (alanina aminotransferase [ALT], aspartato aminotransferase [AST], fosfatase alcalina [FA], gama-glutamil transpeptidase [gama-GT], bilirrubinas e coagulograma) de 50 pacientes internados em 2002 em um hospital terciário com diagnóstico de insuficiência cardíaca. Os doentes foram separados de acordo com sua classe de insuficiência cardíaca e seus dados, comparados estatisticamente. Foram excluídos pacientes com hepatopatia de qualquer etiologia. RESULTADOS: A análise das médias de transaminases revelou aumento significativo apenas nos pacientes da classe IV. Por outro lado, a FA e a gama-GT apresentaram aumento progressivo de acordo com a classe de insuficiência cardíaca. CONCLUSÃO: A insuficiência cardíaca é caracterizada por perfil colestático progressivo de alterações laboratoriais, enquanto as transaminases se elevam apenas na insuficiência cardíaca mais avançada. O entendimento dessas alterações é fundamental para que se evite investigação hepática desnecessária em indivíduos com insuficiência cardíaca.

Estradiol transdérmico e perfil lipídico: efeitos em um grupo específico de mulheres brasileiras pós-menopausadas

FUNDAMENTO: Em mulheres pós-menopausadas, mudanças significantes ocorrem, que podem induzir doenças cardiovasculares, tais como o perfil lipídico aterogênico devido a um aumento nos níveis de colesterol total e LDL, e uma diminuição nos níveis de HDL. A terapia de reposição hormonal (TRH) pode evitar essas mudanças no perfil lipídico. OBJETIVO: Determinar os efeitos da TRH constituída por estradiol transdérmico e acetato de medroxiprogesterona nos parâmetros bioquímicos e lipídicos de mulheres brasileiras pós-menopausadas. MÉTODOS: Este é um estudo prospectivo, longitudinal, aberto, no qual trinta mulheres pós-menopausadas receberam estradiol em gel transdérmico (1 mg/dia) de forma contínua, combinado com acetato de medroxiprogesterona (MPA) (5 mg/dia) por 12 dias/mês. Os seguintes parâmetros foram determinados: colesterol total, triglicérides, lipoproteína de alta densidade (HDL-colesterol), lipoproteína de baixa densidade (LDL-colesterol), lipoproteína de muito baixa densidade (VLDL-colesterol), glicose, aspartato aminotransferase (AST), alanina aminotransferase (ALT), gama-glutamil transferase (GGT) e hormônio folículo estimulante (FSH). RESULTADOS: Os parâmetros do perfil lipídico mostraram uma diminuição não-significante, enquanto os níveis de GGT e FSH apresentaram uma diminuição estatisticamente significante. CONCLUSÕES: O tratamento com estradiol em gel transdérmico não mostrou um impacto significante no perfil lipídico, de forma que não resultou em um efeito benéfico nos marcadores de doenças cardiovasculares, sugerindo que a dose, modo de administração e o tempo de tratamento foram importantes para esses resultados. Além disso, o tratamento com dose baixa e modo de administração transdérmico também demonstrou um significante efeito hepático nessa população. Dessa forma, esse tratamento pode fornecer efeitos interessantes sobre o perfil lipídico em mulheres brasileiras pós-menopausadas.

Níveis de PCR são maiores em pacientes com síndrome coronariana aguda e supradesnivelamento do segmento ST do que em pacientes sem supradesnivelamento do segmento ST

FUNDAMENTO: Há grande interesse no uso de proteína C-reativa de alta sensibilidade (PCR-as) para avaliação de risco. Altos níveis de PCR-as no início da síndrome coronária aguda (SCA), antes da necrose tecidual, pode ser um marcador substituto para comorbidades cardiovasculares. OBJETIVO: Dessa forma, nosso objetivo foi estudar diferentes medidas de seguimento de níveis de PCR-as em pacientes com SCA e comparar as diferenças entre infarto do miocárdio sem elevação do segmento ST (NSTEMI) com pacientes apresentando elevação do segmento ST (STEMI). MÉTODOS: Este é um estudo observacional. Dos 89 pacientes recrutados, 60 apresentavam infarto agudo do miocárdio (IAM). Três níveis seriados de PCR-us, a nível basal na hospitalização antes de 12 horas após inicio dos sintomas, níveis de pico 36-48 horas após hospitalização e níveis de acompanhamento após 4 a 6 semanas foram analisados e comparados entre pacientes com (IAMCSST) e sem supradesnivelamento do segmento ST (IAMSSST). RESULTADOS: Pacientes com IAMCSST tinham IMC significantemente mais alta quando comparados com pacientes IAMSSST. Os níveis de creatino quinase fração MB (CK-MB) e aspartato aminotransferase (AST) eram significantemente mais altos em pacientes com IAMCSST quando comparados com pacientes com IAMSSST (p<0,05). Os níveis de PCR a nível basal e no acompanhamento não diferiram de forma significante entre os dois grupos (p=0,2152 e p=0,4686 respectivamente). Houve uma diferença significante nos níveis de pico de PCR entre os dois grupos. No grupo de pacientes com IAMCSST os níveis foram significantemente mais altos quando comparados aos pacientes com IAMSSST (p=0,0464). CONCLUSÃO: Pacientes com IAMCSST apresentam picos significantemente mais elevados de PCR quando comparados a pacientes IAMSSST. Esses dados sugerem que o processo inflamatório tem um papel independente na patogênese do infarto do miocárdio. Dessa forma, os níveis de PCR podem ajudar na estratificação de risco após o infarto do miocárdio.

Hepatitis B and C prevalences among blood donors in the south region of Brazil

The prevalence of hepatitis B and C infection has been determined in a seroepidemiological survey among blood donors from the south of Brazil (Florianópolis, State of Santa Catarina). These markers has also been correlated with the levels of alanine aminotransferase (ALT), a surrogate marker to prevent post-transfusion hepatitis. Sera from 5000 donors were randomly collected in the period of April to November 1991. The prevalences of HBsAg, anti-HBs and anti-HBc were respectively 0.78, 7.02 and 13.98. The anti-HCV prevalence after confirmation testing with line immunoassay (LIA), was 1.14. Normal values of ALT ( < = 32 U/ml) were found in 59.78, values slightly above the mean (ALT between 32-70 U/ml) in 37.74 and high values of ALT ( > = 70 U/ml) in 2.48. The positivity of anti-HCV antibodies increased with the elevation of ALT levels. This correlation was not observed in relation to HBsAg. There exists a diversity in the recognition of HCV epitopes among HCV positive donors. Via the confirmation test used, we could observe that 94.7 of donors recognize the structural core antigen. Besides that, we observed that 5.26 of the HCV reactive sera recognized only epitopes located in the NS4 and/or NS5 region, indicating the importance of these epitopes for the improvement of assays.

Evaluation of an enzyme immunoassay for hepatitis C virus antibody detection using a recombinant protein derived from the core region of hepatitis C virus genome

This study was undertaken to evaluate an enzyme immunoassay (EIA) for hepatitis C virus antibody detection (anti-HCV), using just one antigen. Anti-HCV EIA was designed to detect anti-HCV IgG using on the solid-phase a recombinant C22 antigen localized at the N-terminal end of the core region of HCV genome, produced by BioMérieux. The serum samples diluted in phosphate buffer saline were added to wells coated with the C22, and incubated. After washings, the wells were loaded with conjugated anti-IgG, and read in a microtiter plate reader (492 nm). Serum samples of 145 patients were divided in two groups: a control group of 39 patients with non-C hepatitis (10 acute hepatitis A, 10 acute hepatitis B, 9 chronic hepatitis B, and 10 autoimmune hepatitis) and a study group consisting of 106 patients with chronic HCV hepatitis. In the study group all patients had anti-HCV detected by a commercially available EIA (Abbott®), specific for HCV structural and nonstructural polypeptides, alanine aminotransferase elevation or positive serum HCV-RNA detected by nested-PCR. They also had a liver biopsy compatible with chronic hepatitis. The test was positive in 101 of the 106 (95%) sera from patients in the study group and negative in 38 of the 39 (97%) sera from those in the control group, showing an accuracy of 96%. According to these results, our EIA could be used to detect anti-HCV in the serum of patients infected with hepatitis C virus.

Hepatitis C and hepatitis B virus infection in different hemodialysis units in Belo Horizonte, Minas Gerais, Brazil

The prevalence, virological and epidemilogical aspects of the hepatitis C virus (HCV) and the hepatitis B virus (HBV) infections vary among hemodialysis patients in different countries. Aiming at analyzing these aspects of HCV and HBV infections in hemodialysis patients in Belo Horizonte, MG, Brazil, we studied three hemodialysis units including 434 patients. Serology was used to detect anti-HCV and HBsAg. Reverse trancriptase nested polymerase chain reaction (RT-nested-PCR) of the 5'-noncoding region was used to detect circulating HCV RNA and restriction fragment length polymorphism analysis for genotyping. Seroprevalence varied from 26.5% to 11.1% for hepatitis C and from 5.9% to 0% for hepatitis B. Risk factors observed for HBV and/or HCV infections were the number of patients per dialysis unit, duration of treatment, number of clinics attended, number of blood units transfused, and lower level scholarity. Alanine aminotransferase levels were altered with a higher frequency in HBV or HCV seropositive patients. Half of ten patients, negative for anti-HCV, had detectable viremia by RT-nested-PCR, indicating that this technique should be used to confirm infections in this group of patients. The HCV genotype 1 was the most frequently observed, followed by the genotype 2, but no correlation was detected between genotype and clinical or epidemiological data.

Cloning and Molecular Characterization of the Schistosoma mansoni Genes RbAp48 and Histone H4

The human nuclear protein RbAp48 is a member of the tryptophan/aspartate (WD) repeat family, which binds to the retinoblastoma (Rb) protein. It also corresponds to the smallest subunit of the chromatin assembly factor and is able to bind to the helix 1 of histone H4, taking it to the DNA in replication. A cDNA homologous to the human gene RbAp48 was isolated from a Schistosoma mansoni adult worm library and named SmRbAp48. The full length sequence of SmRbAp48 cDNA is 1036 bp long, encoding a protein of 308 amino acids. The transcript of SmRbAp48 was detected in egg, cercariae and schistosomulum stages. The protein shows 84% similarity with the human RbAp48, possessing four WD repeats on its C-terminus. A hypothetical tridimensional structure for the SmRbAp48 C-terminal domain was constructed by computational molecular modeling using the b-subunit of the G protein as a model. To further verify a possible interaction between SmRbAp48 and S. mansoni histone H4, the histone H4 gene was amplified from adult worm genomic DNA using degenerated primers. The gene fragment of SmH4 is 294 bp long, encoding a protein of 98 amino acids which is 100% identical to histone H4 from Drosophila melanogaster.

Detection of hepatitis C virus RNA by in situ hybridization in paraformaldehyde fixed biopsies

Fourteen hepatitis C virus (HCV) chronically infected patients were submitted to routine liver biopsy for histological evaluation. Liver samples were assayed to HCV-RNA by in situ hybridization, using digoxigenin labeled probe. HCV genotypes were found to be predominantly type 1 (71.4%), followed by genotype 3 (21.4%), and genotype 2 (7.2%). Alanine-aminotransferase levels were raised in 10 patients. The histopathological scores were minimal (21.4%), mild (57.2%), and moderate (21.4%). Viral RNA was detected in liver cells from nine patients (64.3%). ISH method provides localization and poor confirmation of HCV RNA in the liver tissue of HCV chronic patients.

Morphological studies in a model for dengue-2 virus infection in mice

One of the main difficulties in studying dengue virus infection in humans and in developing a vaccine is the absence of a suitable animal model which develops the full spectrum of dengue fever, dengue haemorrhagic fever, and dengue shock syndrome. It is our proposal to present morphological aspects of an animal model which shows many similarities with the dengue infection in humans. BALB/c mice were intraperitoneally infected with non-neuroadapted dengue virus serotype 2 (DENV-2). Histopathological and morphometrical analyses of liver tissue revealed focal alterations along the infection, reaching wide-ranging portal and centrolobular veins congestion and sinusoidal cell death. Additional ultrastructural observations demonstrated multifocal endothelial injury, platelet recruitment, and alterated hepatocytes. Dengue virus antigen was detected in hepatocytes and in the capillar endothelium of the central lobular vein area. Liver function tests showed high levels of aspartate transaminase and alanine transaminase enzyme activity. Lung tissue showed interstitial pneumonia and mononuclear cells, interseptal oedema, hyperplasia, and hypertrophy of the bronchiolar epithelial cells. DENV-2 led to a transient inflammatory process, but caused focal alterations of the blood-exchange barrier. Viremia was observed from 2nd to 11th day p.i. by isolation of DENV-2 in C6/36 mosquito cell line inoculated with the supernatant of macerated liver, lung, kidney, and cerebellum tissues of the infected mice.

Epidemiological aspects of hepatitis C virus infection among renal transplant recipients in Central Brazil

An investigation was conducted involving 255 renal transplant recipients in the state of Goiás, Central Brazil, to determine the prevalence of hepatitis C virus (HCV), its risk factors, the genotypes involved, and the level of alanine aminotransferase (ALT) present in the patients. All serum samples were tested for anti-HCV antibodies and HCV RNA. Forty-one patients were anti-HCV and/or HCV RNA positive, resulting in an overall HCV infection prevalence of 16.1% (95% CI: 11.9-21.3). A multivariate analysis of risk factors showed that a history of blood transfusions without anti-HCV screening, the length of time spent on hemodialysis, and renal transplantation before 1994 are all associated with HCV positivity. In HCV-positive patients, only 12.2% had ALT levels above normal. Twenty-eight samples were genotyped as genotype 1, subtypes 1a (62.5%) and 1b (31.3%), and two samples (6.2%) were genotype 3, subtype 3a. These data show a high prevalence of HCV infection and low ALT levels in the studied population. The risk factor analysis findings emphasize the importance of public health strategies such as anti-HCV screening of candidate blood and organ donors, in addition to the stricter adoption of hemodialysis-specific infection control measures. The present study also demonstrates that HCV genotype 1 (subtype 1a) is predominant in this population.

Hepatitis B virus genotypes in Southeast Brazil and its relationship with histological features

Data concerning the relationship between hepatitis B virus (HBV) genotypes and liver histology are scarce. The aim of this study was to compare HBV non-B and non-C genotypes according to demographic features, clinical status, HBV-DNA levels and liver histology in Rio de Janeiro. One hundred twenty one consecutive chronic HBV-infected patients were enrolled during two-year period and data were prospectively collected. Sera were tested for HBV genotyping using restriction fragment length polymorphism. Liver biopsy was obtained from patients with either increased alanine aminotransferase (ALT) or HBV-DNA levels. Genotype A was the most common, found in 82 (68%) patients, followed by F in 19 (15%), D in 17 (14%), B in one (1%) and C in two (2%). There was no association between HBV genotypes A, D and F and gender (p = 0.37), age (p = 0.78), race (p = 0.22), mode of infection (p = 0.94), HB "e" antigen status (p = 0.37) and HBV-DNA levels (p = 0.47). The ALT levels were lower in genotype D (75%) compared with A (47%) and F (55%) (p = 0.05). Liver biopsy showed lower inflammation [histological activity index (HAI) = 4] and fibrosis (F) (= 0) scores in genotype D than in genotypes A (HAI = 5, p < 0.001; F = 2, p = 0.008) or F (HAI = 5, p = 0.009; F = 2, p = 0.01). Genotype A was the most prevalent in chronic HBV-infected patients and genotype D patients presented with less intense liver disease.

Performance of diagnostic biomarkers in predicting liver fibrosis among hepatitis C virus-infected Egyptian children

The aim of the present study was to identify specific markers that mirror liver fibrosis progression as an alternative to biopsy when biopsy is contraindicated, especially in children. After liver biopsies were performed, serum samples from 30 hepatitis C virus (HCV) paediatric patients (8-14 years) were analysed and compared with samples from 30 healthy subjects. All subjects were tested for the presence of serum anti-HCV antibodies. Direct biomarkers for liver fibrosis, including transforming growth factor-β1, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), hyaluronic acid (HA), procollagen type III amino-terminal peptide (PIIINP) and osteopontin (OPN), were measured. The indirect biomarkers aspartate and alanine aminotransferases, albumin and bilirubin were also tested. The results revealed a significant increase in the serum marker levels in HCV-infected children compared with the healthy group, whereas albumin levels exhibited a significant decrease. Significantly higher levels of PIIINP, TIMP-1, OPN and HA were detected in HCV-infected children with moderate to severe fibrosis compared with children with mild fibrosis (p < 0.05). The diagnostic accuracy of these direct biomarkers, represented by sensitivity, specificity and positive predictive value, emphasises the utility of PIIINP, TIMP-1, OPN and HA as indicators of liver fibrosis among HCV-infected children.

The TcI and TcII Trypanosoma cruzi experimental infections induce distinct immune responses and cardiac fibrosis in dogs

Trypanosoma cruzi infection may be caused by different strains with distinct discrete typing units (DTUs) that can result in variable clinical forms of chronic Chagas disease. The present study evaluates the immune response and cardiac lesions in dogs experimentally infected with different T. cruzi strains with distinct DTUs, namely, the Colombian (Col) and Y strains of TcI and TcII DTU, respectively. During infection with the Col strain, increased levels of alanine aminotransferase, erythrocytes, haematocrit and haemoglobin were observed. In addition, CD8+ T-lymphocytes isolated from the peripheral blood produced higher levels of interleukin (IL)-4. The latter suggests that during the acute phase, infection with the Col strain may remain unnoticed by circulating mononuclear cells. In the chronic phase, a significant increase in the number of inflammatory cells was detected in the right atrium. Conversely, infection with the Y strain led to leucopoenia, thrombopoenia, inversion of the ratio of CD4+/CD8+ T-lymphocytes and alterations in monocyte number. The Y strain stimulated the production of interferon-γ by CD4+ and CD8+ T-lymphocytes and IL-4 by CD8+ T-cells. In the chronic phase, significant heart inflammation and fibrosis were observed, demonstrating that strains of different DTUs interact differently with the host.

Experimental infection with the Toxoplasma gondii ME-49 strain in the Brazilian BR-1 mini pig is a suitable animal model for human toxoplasmosis

Toxoplasma gondii causes toxoplasmosis, a worldwide disease. Experimentation with pigs is necessary for the development of new therapeutic approaches to human diseases. BR-1 mini pigs were intramuscularly infected with T. gondii with tachyzoites (RH strain) or orally infected with cysts (ME-49 strain). Haematology and serum biochemistry were analysed and buffy coat cells were inoculated in mice to determine tachyzoite circulation. No alterations were observed in erythrocyte and platelet values; however, band neutrophils increased seven days after infection with ME-49. Serology of the mice inoculated with pig blood leucocytes revealed circulating ME-49 or RH strain tachyzoites in the pigs' peripheral blood at two and seven or nine days post-infection. The tachyzoites were also directly observed in blood smears from the infected pigs outside and inside leucocytes for longer periods. Alanine-aminotransferase was high at days 21 and 32 in the RH infected pigs. After 90 days, the pigs were euthanised and their tissue samples were processed and inoculated into mice. The mice serology revealed the presence of parasites in the hearts, ileums and mesenteric lymph nodes of the pigs. Additionally, cysts in the mice were only observed after pig heart tissue inoculation. The infected pigs presented similar human outcomes with relatively low pathogenicity and the BR-1 mini pig model infected with ME-49 is suitable to monitor experimental toxoplasmosis.

Isoenzymatic variability in wild potatoes

Two species of wild potato Solanum commersonii, subspecies commersonii and malmeanum, and S. chacoense, subspecies muelleri occur in southern Brazil. Their rusticity and easy adaptation to extreme climatic conditions make them valuable for breeding programs. The objective of this work was to analyze the isoenzymatic variability of 113 clones of wild potato subspecies. They were collected and maintained at Embrapa-Centro de Pesquisa Agropecuária de Clima Temperado, at Pelotas, RS, Brazil. Enzymes involved in energetic (group I) or in peripherical (group II) metabolism constituted the material used. Polyacrylamide horizontal gel electrophoresis was used to analyze peroxidase, aspartate transaminase, phosphoglucomutase and isocitrate dehydrogenase isoenzymes. Solanum spp. has considerable genetic variability for isoenzymatic patterns. Cluster analysis classified the clones into 51 subgroups, based on electrophoretic variants of group I enzymes, and into 89, when group II enzyme variants were added. Genotypic differentiation of S. chacoense muelleri in relation to S. commersonii commersonii and S. commersonii malmeanum is evident when expressed through similarity and cluster analysis.