Biomedical subjects

Mitermayer G Reis

Publications and source records attributed to Mitermayer G Reis.

18 recordsLinked to original sources

PubMed2007

High serum nitric oxide levels in patients with severe leptospirosis.

Leptospirosis is a globally distributed zoonosis of major public health importance and is associated with severe disease manifestations such as acute renal failure and pulmonary haemorrhage syndrome. However, the extent to which the pathogenesis of leptospirosis mimics sepsis caused by Gram-negative bacteria remains unknown. The aim of this study was to evaluate serum levels of nitric oxide (NO) in patients diagnosed with severe leptospirosis. Sera from 35 confirmed cases of severe leptospirosis and 13 healthy subjects were analysed. Patients with severe leptospirosis had significantly higher NO levels compared to healthy individuals (30.82+/-10.90 microM versus 3.86+/-1.34 microM, P < 0.001), indicating that this immune mediator plays a role in the underlying systemic inflammatory response.

Adolescent↗

PubMed2006

Schizodeme analysis of Trypanosoma cruzi Colombian strain clones isolated from the acute phase of murine infection.

Colombian strain of Trypanosoma cruzi, biodeme Type III (T. cruzi I), has been cloned by micromanipulation at two phases of the acute infection: early (10 days ) and advanced (30 days). Twelve clones were obtained therefrom. Characterization by their biological and biochemical behavior showed an identity among the several clones and their parental strain, albeit with different degrees of virulence. Molecular characterization of the kinetoplast DNA (kDNA) after amplification by polymerase chain reaction revealed identical profiles of the bands from the kDNA minicircle by the analysis of restriction fragment length polymorphism for the isolated clones, their parental strain, and to the clones isolated at two different phases of the infection. Results suggest the predominance of a "principal clone", in the composition of the Colombian strain, responsible for the biological and biochemical behavior. However, no relationship was detected between the molecular profile of kDNA and the degree of virulence presented by the several clones.

Acute Disease↗

PubMed2006

Biochemical and immunologic predictors of efficacy of treatment or reinfection risk for Schistosoma mansoni.

Most Schistosoma mansoni infections are egg-negative after a single dose of oxamniquine. A cohort of 661 infected children was treated at 6-month intervals and assessed for nutritional and parasitological status. Initial biochemical and immunologic markers were measured in a subset of 84 children. All were treated at the start of therapy and at 6 months. Immunoglobulins only served as markers for active infection. No markers were predictive of cure or reinfection, except initial infection intensity and serum low-density lipoprotein. Ten percent were persistently infected and had no change in infection intensity at any time-point. Several factors suggest that this group was biologically different. In addition to failing to reduce their worm burden, they had significantly higher initial intensity of infection (100 versus 65 eggs/g, P = 0.001) and significantly lower initial serum low-density lipoprotein (72 versus 104 mg/dL, P = 0.045). The biologic plausibility of this observation is discussed.

Adolescent↗

PubMed2006

Moderate- and low-intensity co-infections by intestinal helminths and Schistosoma mansoni, dietary iron intake, and anemia in Brazilian children.

To determine the role of moderate- and low-intensity infections with Schistosoma mansoni and intestinal helminths (hookworm, Trichuris trichiura, Ascaris lumbricoides) on the prevalence of anemia and their relationship to iron consumption, a cross-section of 1,709 children in rural Brazil was studied. All participants were selected for infection with one or multiple helminthic parasites, and demographic, anthropometric, and dietary intake were surveyed. The prevalence and intensity were as follows: hookworm infection, 15.7% and 8.6 eggs/g; T. trichiura, 74.8% and 190.5 eggs/g; A. lumbricoides, 63% and 1,905.5 eggs/g; S. mansoni, 44.5% and 60.3 eggs/g. There was no increase in odds ratio for anemia with any combination of intestinal helminths without S. mansoni infection. By logistic regression, the odds ratio for having anemia when infected with S. mansoni and two intestinal helminths was 1.7 (95% CI, 1.1-2.5) and for S. mansoni and three intestinal helminths was 2.4 (95% CI, 1.2-4.6) compared with children with a single parasite species. Children with an adequate intake of iron had no increased odds of anemia independent of the combination of parasite infections.

Adolescent↗

PubMed2005

Prevalence of hepatitis C virus infection in north-eastern Brazil: a population-based study.

In general, the prevalence and genotype distribution of hepatitis C virus (HCV) are estimated based on the ambulatory clinic or hospital population. In the present work, a population-based study was conducted to estimate the prevalence of HCV infection in Salvador, Brazil. A total of 1308 serum samples were collected from 30 "sentinel areas", and the prevalence of HCV infection was determined by ELISA and confirmed by recombinant immunoblot assay and RT-PCR. The overall prevalence of HCV infection was 1.5% (20/1308). Prevalence was greater among those aged 35 years or older and those with more education. Genotype 3 was the most common (53.3%), followed by genotypes 1 (40%) and 2 (6.7%). These observations are different from those found in a prior survey of hospital and ambulatory patients in Salvador, who were most frequently infected with genotype 1, followed by genotypes 3 and 2, respectively.

Adolescent↗

PubMed2005

Detection of hepatitis C virus RNA in saliva is not related to oral health status or viral load.

Hepatitis C is a worldwide public health problem and its transmission is clearly associated with the parenteral route, however, the virus has also been isolated from other body fluids. Hepatitis C virus (HCV) RNA has been detected in saliva, yet the relationship between HCV and oral pathology is not clearly understood. Therefore, an investigation on HCV-RNA in saliva and its correlation with oral pathology was undertaken. Saliva and blood samples were collected from 50 anti-HCV positive patients and from 25 patients with non-HCV chronic liver disease. HCV-RNA was detected in all of the saliva samples from the HCV positive group. None of the saliva or serum samples from the non-HCV group were positive for HCV-RNA. The patients were examined for dental and oral health (dentate, partially dentate, edentulous, evidence of gum disease, or mucosal lesions); however, no correlation was found between HCV-RNA in saliva, oral health, and viral load. These results suggest that HCV-RNA presence in saliva is independent of the viral load and the oral pathology of HCV positive individuals.

Adult↗

PubMed2005

Leptospirosis.

PURPOSE OF REVIEW: Leptospirosis, a spirochaetal zoonotic disease, has been recognized as an important emerging infectious disease in the last 10 years. This review addresses the issues in the epidemiology, diagnosis and clinical management which confront public health responses, and highlights the progress made towards understanding the Leptospira genome, biology and pathogenesis. RECENT FINDINGS: Leptospirosis has spread from its traditional rural base to become the cause of epidemics in poor urban slum communities in developing countries. Mortality from severe disease forms, Weil's disease and severe pulmonary haemorrhage syndrome, is high (>10% and >50%, respectively) even when optimal treatment is provided. Moreover, the overall disease burden is underestimated, since leptospirosis is a significant cause of undifferentiated fever and frequently not recognized. Barriers to addressing this problem have been the lack of an adequate diagnostic test and effective control measures. China and Brazil, countries in which leptospirosis is a major health problem, have completed the sequence of the Leptospira interrogans genome. Together with new genetic tools and proteomics, new insights have been made into the biology of Leptospira and the mechanisms used to adapt to host and external environments. Surface-exposed proteins and putative virulence determinants have been identified which may serve as sub-unit vaccine candidates. SUMMARY: Major progress has been made in the basic research of leptospirosis. Future challenges will be to translate these advances into public health measures for developing countries. Yet the most effective responses may be interventions that directly address the determinants of poverty, such as poor sanitation, which are often responsible for transmission.

Genome, Bacterial↗

PubMed2004

Diagnostic performance of anti-beta2 glycoprotein I and anticardiolipin assays for clinical manifestations of the antiphospholipid syndrome.

The objective of the present study was to analyse the performance of the tests for detection of anti-beta2 glycoprotein I (beta2 GP I) and anticardiolipin (aCL) antibodies for identification of clinical manifestations of the antiphospholipid syndrome (APS). Patients with systemic lupus erythematosus (SLE) as well as carriers of infectious diseases such as Kala-azar, syphilis and leptospirosis were studied. Particular interest was given to the presence of clinical complications related to APS. Anticardiolipin and anti-beta2 GP I antibodies were searched using an enzyme-linked immunosorbent assay (ELISA) assay. Clinical manifestations of APS were observed in 34 of the 152 patients (22.3%) with SLE and no patient with infectious disease had such manifestations. Antibodies to cardiolipin in moderate or high levels and anti-beta2 GP I were detected in 55 of 152 (36.1%) and 36 of 152 (23.6%) patients with SLE, respectively, and in 2 of 30 (6.6%) and 16 of 30 (53.3%) patients with Kala-azar, in 9 of 39 (23%) and 6 of 34 (17.6%) patients with leptospirosis, and 14 of 74 (18.9%) and 8 of 70 (11.4%) cases of syphilis, respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and likelihood ratio (LR) of the anti-beta2 GP I test for the identification of the clinical manifestation of APS were, respectively, 29% [95% confidence interval (CI) = 24%-34%], 78% (95% CI = 73-83%), 15% (95% CI = 11-19%), 89% (95% CI = 85-93%) and 1.38. Regarding the aCL assay, the figure was 29% (95% CI = 24-34%), 76% (95% CI = 71-81%), 14% (95% CI = 10-18%), 89% (95% CI = 86-92%) and 1.26. As the validity and performance of the anti-beta2 GP I assay were similar to the aCL in demonstrating the presence of clinical phenomena associated with APS and due to the difficulties in performing as well as the lack of standardisation of the anti-beta2 GP I test, we suggest that the test for aCL should continue to be the first one performed when the presence of APS is suspected.

Adult↗

PubMed2003

Trypanosoma cruzi: susceptibility to chemotherapy with benznidazole of clones isolated from the highly resistant Colombian strain.

The present investigation was performed to evaluate the susceptibility of seven clones isolated from the highly resistant Colombian strains, prototype of Biodeme Type III. Seven clones previously obtained, showed a phenotypic homogeneity and high similarity with the parental strain. Eight groups of 30 mice were inoculated with one of seven clones or the parental strain; 20 were treated with benznidazole (100mg/kg/day) and 10 were untreated controls. Cure evaluations were done by parasitological and serological tests and PCR. Cure rates varied from 0% (null) to 16.7%. Correlation between positivity of parasitological and serological tests with positive PCR reached 37%. The results demonstrated the high resistance of the clones, suggesting the predominance of a highly resistant principal clone in this strain. The findings apparently indicate that the possibility of cure is minimal for patients infected with this biodeme; a fact that could affect the control of Chagas' disease through treatment of chronically infected people.

Animals↗

PubMed2003

Pathogenic Leptospira species express surface-exposed proteins belonging to the bacterial immunoglobulin superfamily.

Proteins with bacterial immunoglobulin-like (Big) domains, such as the Yersinia pseudotuberculosis invasin and Escherichia coli intimin, are surface-expressed proteins that mediate host mammalian cell invasion or attachment. Here, we report the identification and characterization of a new family of Big domain proteins, referred to as Lig (leptospiral Ig-like) proteins, in pathogenic Leptospira. Screening of L. interrogans and L. kirschneri expression libraries with sera from leptospirosis patients identified 13 lambda phage clones that encode tandem repeats of the 90 amino acid Big domain. Two lig genes, designated ligA and ligB, and one pseudogene, ligC, were identified. The ligA and ligB genes encode amino-terminal lipoprotein signal peptides followed by 10 or 11 Big domain repeats and, in the case of ligB, a unique carboxy-terminal non-repeat domain. The organization of ligC is similar to that of ligB but contains mutations that disrupt the reading frame. The lig sequences are present in pathogenic but not saprophytic Leptospira species. LigA and LigB are expressed by a variety of virulent leptospiral strains. Loss of Lig protein and RNA transcript expression is correlated with the observed loss of virulence during culture attenuation of pathogenic strains. High-pressure freeze substitution followed by immunocytochemical electron microscopy confirmed that the Lig proteins were localized to the bacterial surface. Immunoblot studies with patient sera found that the Lig proteins are a major antigen recognized during the acute host infection. These observations demonstrate that the Lig proteins are a newly identified surface protein of pathogenic Leptospira, which by analogy to other bacterial immunoglobulin superfamily virulence factors, may play a role in host cell attachment and invasion during leptospiral pathogenesis.

Amino Acid Sequence↗

PubMed2003

[Risk factors for iron-deficiency anemia in children and adolescents with intestinal helminthic infections].

OBJECTIVE: To investigate risk factors for iron-deficiency anemia in children and adolescents (7 to 17 years of age) with intestinal helminthic infections. METHODS: A cross-sectional study was carried out with 1 709 children and adolescents living in Jequié, a town in the state of Bahia, Brazil, who had mild to moderate infection by Schistosoma mansoni, Ascaris lumbricoides, Trichuris trichiura, or hookworms. We obtained data concerning hemoglobin levels (using a portable hemoglobinometer), dietary habits (24-hour dietary recall), parasitic infections (Kato-Katz method), sanitary conditions (water supply, sewage connection, garbage collection), housing conditions (type of construction, number of persons per room), income, and amount of schooling of the parents or guardians. The risk factors for anemia were studied based on a hierarchical model of causality. RESULTS: The prevalence of parasitic infection was 74.8% for T. trichiura, 63.0% for A. lumbricoides, 55.5% for S. mansoni, and 15.7% for hookworms. Among the children and adolescents studied 32.2% were anemic. After adjustment for confounding variables, the results of the multivariate analysis showed that the following variables were significantly associated with anemia: per capita family income below US$ 27 (equal to one fourth of the Brazilian minimum wage), male sex, age of 7 to 9 years, and inadequate intake of bioavailable iron. CONCLUSIONS: The initiatives to control anemia in the group at greatest risk, as identified in this study, should seek to increase the consumption of iron-rich foods, boost the bioavailability of the iron ingested, and improve socioenvironmental conditions.

Adolescent↗

PubMed2003

Antibodies to Schistosoma mansoni in human cerebrospinal fluid.

Cerebrospinal fluid (CSF) and serum samples from patients suspected of having neuroschistosomiasis (NS) were evaluated by an enzyme-linked immunosorbent assay. Monoclonal antibodies of various immunoglobulin isotypes (IgM, IgA, IgE, total IgG, IgG1, IgG2, IgG3, and IgG4) were used to detect antibodies against Schistosoma mansoni soluble egg antigen (SEA) and soluble worm adult preparation (SWAP). Of the 83 CSF samples tested, 55% were reactive to SEA (26% were reactive only to SEA and 29% to both SEA and SWAP), 34% were reactive to SWAP (5% only to SWAP and 29% to both SEA and SWAP), and 40% were not reactive with any antigen. Cases that tested positive for SWAP in CSF and negative in serum were not found. Samples with high specific IgG antibody titers were selected for immunoglobulin isotype profiling. In the CSF samples, the antibodies against SEA and SWAP were mainly IgM, IgG1, and IgG4, although other immunoglobulins were also detected. Interestingly, nine patients had high levels of IgG1 only in the CSF. These results suggest that there is local synthesis of IgG1, and that this isotype could be an important immunologic marker in the diagnosis of NS.

Adolescent↗

PubMed2002

Prevention of Haemophilus influenzae type b (Hib) meningitis and emergence of serotype replacement with type a strains after introduction of Hib immunization in Brazil.

Surveillance for Haemophilus influenzae meningitis cases was performed in Salvador, Brazil, before and after introduction of H. influenzae type b (Hib) immunization. The incidence of Hib meningitis decreased 69% during the 1-year period after initiation of Hib immunization (from 2.62 to 0.81 cases/100,000 person-years; P<.001). In contrast, the incidence for H. influenzae type a meningitis increased 8-fold (from 0.02 to 0.16 cases/100,000 person-years; P=.008). Pulsed-field gel electrophoretic analysis demonstrated that H. influenzae type a isolates belonged to 2 clonally related groups, both of which were found before Hib immunization commenced. Therefore, Hib immunization contributed to an increased risk for H. influenzae type a meningitis through selection of circulating H. influenzae type a clones. The risk attributable to serotype replacement is small in comparison to the large reduction in Hib meningitis due to immunization. However, these findings highlight the need to maintain surveillance as the use of conjugate vaccines expands worldwide.

Bacterial Capsules↗

PubMed2002

Sensitivity of polymerase chain reaction for detection of known aliquots of Trypanosoma cruzi in the blood of mice: an in vitro study.

To evaluate the sensitivity of polymerase chain reaction (PCR) to reveal known number of trypomastigote in the blood of mice, three separate experiments were done. First: To eight samples of 500 microliters of normal mice blood, one aliquot of 1, 2, 3, 4, 5, 10, and 50 trypomastigotes respectively, were added. Second and third: 10 aliquots with 1 and 10 with 2 trypomastigotes were added to samples of 500 microliters of normal mice blood. Positive control: 500 microliters of blood containing 100,000 trypomastigotes. For kDNA minicircles amplification by PCR the primers: S35 and S36 were used. PCR revealed products of 330 b.p in the positive controls. When only one sample with the aliquots of 1 or 2 trypomastigotes was examined, results were negative; results were positive with aliquots of 3 to 50 trypomastigotes. In the 2nd and 3rd experiments, 9/10 aliquots with one parasite and 9/10 with 2 trypomastigotes were positive revealing a high sensitivity of this reaction. In conclusion, the presence of one single parasite in 500 microliters of blood, is enough for a positive PCR. This method could be used as a complement to the various parasitological cure tests in treated mice, when low volumes of blood are individually examined.

Animals↗

PubMed2002

Population-based differences in Schistosoma mansoni- and hepatitis C-induced disease.

Two populations with differing histories of Schistosoma mansoni and hepatitis C infection were compared directly for severity of disease and extent of comorbidity. Demographic, parasitologic, and ultrasound surveys were conducted on 2038 Egyptians and on 2120 Kenyans. Hepatitis B and C serologies and transaminase levels were obtained from a subset at each site. Despite significantly lower prevalence and intensity of infection, Egyptians had a higher prevalence of severe schistosomal fibrosis than Kenyans (36.8% vs. 4.6%). Hepatitis C infection was 3 times more prevalent among Egyptians, and evidence of hepatocellular damage was significantly greater among Egyptians. There was no interaction between S. mansoni infection or disease and the prevalence or severity of hepatitis C. For both infections, the intensity or prevalence of infection was a poor predictor of morbidity. The prevalence of disease in the Egyptian population from different pathogens suggests a generalized susceptibility to inflammatory liver disease.

Adolescent↗

PubMed2002

Population-based survey of antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae from meningitis patients in Salvador, Brazil.

Penicillin-nonsusceptible strains were isolated from 15% of 303 individuals with pneumococcal meningitis identified during a 4-year surveillance study in Salvador, Brazil. The estimated rate of coverage of the seven-valent conjugate vaccine was 74% among patients <5 years of age and 94% among those infected with nonsusceptible isolates, indicating that the use of conjugate vaccines may be an approach to the control of emerging penicillin resistance in Brazil.

Anti-Bacterial Agents↗

PubMed2002

Population-based case-control investigation of risk factors for leptospirosis during an urban epidemic.

Between March and October 2000, 157 suspected cases of leptospirosis hospitalized with complications of Weil's syndrome and a mortality of 8% were identified in Salvador, Brazil. We conducted a population-based case-control study to identify risk factors for acquisition of leptospirosis in neighborhoods with high endemicity during the rainy season-associated urban epidemic. Sixty-six (65%) of 101 laboratory-confirmed cases and 125 age and sex-matched healthy neighborhood controls were interviewed. Residence in proximity to an open sewer (matched odds ratio [OR] = 5.15, 95% confidence interval [CI] = 1.80-14.74), peri-domiciliary sighting of rats (OR = 4.49, 95% CI = 1.57-12.83), sighting groups of five or more rats (OR = 3.90, 95% CI = 1.35-11.27), and workplace exposure to contaminated environmental sources (OR = 3.71, 95% CI = 1.35-10.17) were found to be independent risk factors for acquiring disease. Some of these risk factors are amenable to focused interventions, which include provision of closed drainage systems for sewage and reduction of rodent populations in the peri-domicilary environment. Environmental control of transmission may help to greatly reduce the incidence of severe leptospirosis.

Adolescent↗

PubMedDate not supplied

[Epidemiology of schoolchildren's cognitive development in Jequié, Bahia State, Brazil: assessment procedures and general results].

This paper describes the methodology, applicability and utility of the Raven Progressive Matrix (Raven Test) and the Brazilian Intellectual Probe (TSI), comparing them with school achievement in a typical medium-size urban community of Northeastern Brazil. 388 schoolchildren (7-17 years old) were examined, with 371 Raven tests applied. Only 231 TSIs were completed, since 106 students were illiterate. School grades were obtained for all participants. A questionnaire evaluating school resources, and teacher profiles was answered by 200 teachers. Raven and TSI test scores were highly correlated (r = 0.53, p < 0.001), but both correlated weakly with overall school grade (r = 0.22, p < 0.001 and r = 0.12, p < 0.07 respectively). For individual school grades, the Raven scores showed statistically significant correlation with all subjects, while the Brazilian TSI presented statistically significant correlation only with geography, history and sciences. Boys' mean scores were higher than girls' for both the Raven and the TSI Tests, but for the school grades girls performed better. In general, level of cognitive development was below that expected for children in the age-group analyzed.

Achievement↗