57 results on '"AZEVEDO, R."'
Search Results
2. First record of Palombitrema triangulum (Suriano, 1981) Suriano, 1997 (Monogenea: Dactylogyridae) from freshwater fishes in Brazil.
- Author
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Abdallah, V. D., Azevedo, R. K., and Silva, R. J.
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MONOGENEA ,FRESHWATER fishes ,FISH morphology ,HELMINTHS ,CYPHOCHARAX - Abstract
Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2015
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3. First record of an epibiont protozoan Epistylis sp. (Ciliophora, Peritrichia) attached to Ergasilus chelangulatus (Ergasilidae) in Brazil.
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Azevedo, R. K., Brandão, H., Abdallah, V. D., and Silva, R. J.
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PROTOZOA ,CILIATA ,SCIENTIFIC observation ,GEOGRAPHICAL distribution of fishes ,RIVERS - Abstract
Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
- Full Text
- View/download PDF
4. Unilatus unilatus Mizelle & Kritsky, 1967 (Monogenea, Ancyrocephalinae) in Hypostomus spp. (Siluriformes, Loricariidae) from the Chavantes reservoir, São Paulo State, Brazil.
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Zica, É., Abdallah, V., Azevedo, R., Wunderlich, A., Carvalho, E., and Silva, R.
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HYPOSTOMUS ,ANIMAL morphology ,HELMINTHS - Abstract
In this paper, the occurrence and new morphological data of Unilatus unilatus Mizelle et Kritsky, 1967 from the gills of Hypostomus strigaticeps (Regan, 1907), Hypostomus regani (Ihering, 1905), and Hypostomus iheringii (Regan, 1908) from the Chavantes reservoir, São Paulo State, Brazil are reported. Unilatus unilatus from this reservoir presents differences in relation to the holotype previously described such as, eggs with no bifid or trifid filament and a rounded termination, anterior bar slightly curved with a posterior projection, and posterior bar which may present three shapes. This is the first record of U. unilatus in southeastern Brazil outside the Amazon River Basin, with H. strigaticeps, H. regani and H. iheringii as new hosts. [ABSTRACT FROM AUTHOR]
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- 2012
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5. First Record of an Epibiont Protozoan Epistylis Sp. (Ciliophora, Peritrichia) Attached to Amplexibranchius Bryconis Thatcher & Paredes, 1985 (Copepoda, Ergasilidae) From Peixe's River, State of São Paulo, Brazil.
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Abdallah, V. D., Azevedo, R. K. De, and Silva, R. J. Da
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PARASITISM , *EPISTYLIS , *COPEPODA , *PROCHILODUS lineatus - Abstract
The article focuses on the detection of a protozoan epistylis species attached to parasitic copepod from prochilodus lineatus fishes at Peixe's River in the State of Sao Paulo, Brazil. It mentions a study that involved the examination of the fishes for parasitic crustacean infestation, which showed that the infestation can cause death to a fish by affecting respiration and allowing for secondary bacterial infection. Furthermore, the negative effect of ciliate protozoan on copepods is mentioned.
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- 2011
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6. Ectoparasites as numerical dominant species in parasite community of Trachelyopterus striatulus (Siluriformes: Auchenipteridae) from Guandu River, southeastern Brazil.
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Mesquita, R. L. B., Azevedo, R. K., Abdallah, V. D., and Luque, J. L.
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AUCHENIPTERIDAE ,RIVERS ,CATFISHES ,FISH parasites ,MONOGENEA - Abstract
Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2011
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- View/download PDF
7. Hepatitis A incidence rate estimates from a pilot seroprevalence survey in Rio de Janeiro, Brazil.
- Author
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Struchiner, CJ, de Almeida, LM, de Azevedo, RS, Massad, E, Struchiner, C J, de Almeida, L M, and de Azevedo, R S
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AGE distribution ,COMPARATIVE studies ,ENZYME-linked immunosorbent assay ,EPIDEMIOLOGICAL research ,HEPATITIS A ,HEPATITIS viruses ,RESEARCH methodology ,MEDICAL cooperation ,RESEARCH ,SANITATION ,VIRAL antibodies ,PILOT projects ,EVALUATION research ,DISEASE incidence ,DISEASE prevalence ,RETROSPECTIVE studies - Abstract
Background: To assess the impact of water sanitation and sewage disposal, part of a major environmental control programme in Rio de Janeiro, we carried out sero-prevalence studies for Hepatitis A virus (HAV) in three micro-regions in Rio de Janeiro. Each region varied with regard to level of sanitation. We are interested in assessing the discriminating power of age-specific prevalence curves for HAV as a proxy for improvement in sanitation. These curves will serve as baseline information to future planned surveys as the sanitation programme progresses.Methods: Incidence rate curves from prevalence data are estimated parametrically via a Weibull-like survival function, and non-parametrically via maximum likelihood and monotonic splines. Sera collected from children and adults in the three areas are used to detect antibodies against HAV through ELISA.Results: We compare baseline incidence curves at the three sites estimated by the three methods. We observe a strong negative correlation between level of sanitation and incidence rates for HAV infection. Incidence estimates yielded by the parametric and non-parametric approaches tend to agree at early ages in the microregion showing the best level of sanitation and to increasingly disagree in the other two.Conclusion: Our results support the choice of HAV as a sentinel disease that is associated with level of sanitation. We also introduce monotonic splines as a novel non-parametric approach to estimate incidence from prevalence data. This approach outperforms current estimating procedures. [ABSTRACT FROM AUTHOR]- Published
- 1999
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8. HIV infection and related risk behaviours in a disadvantaged youth institution of São Paulo, Brazil.
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Zanetta, D. M. T., Strazza, L., Azevedo, R. S., Carvalho, H. B., Massad, E., Menezes, R. X., Ferreira, D. P., Burattini, M. N., and Zanetta, D M
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HIV infections ,YOUTHS' sexual behavior ,SEXUALLY transmitted diseases ,PUBLIC health - Abstract
In order to study the prevalence of HIV and related risky behaviours among disadvantaged youth, we interviewed and bled, between December 1994 and April 1995, 1122 young males and 93 young females who were serving time in FEBEM, a state institution that cares for homeless and offender youth of São Paulo, Brazil. Our questionnaire covered the following areas: sexual practices and use of illicit drugs; knowledge of HIV and STDs and their prevention; and myths and beliefs about AIDS. Seroprevalence of HIV was assessed and related with risk-taking behaviours by means of uni-, bi- and multivariate analysis. We found 2.6% of the males and 10.3% of the females to be positive to HIV. The prevalence of hepatitis C virus (HCV) antibodies resulted in 5.9% for males and 4.6% for females, respectively. The risk for parenterally transmitted HIV among the males was higher than that for sexually related transmission. The inverse relationship was found among the females. [ABSTRACT FROM AUTHOR]
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- 1999
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9. Safflower genetic diversity based on agronomic characteristics in Mato Grosso state, Brazil, for a crop improvement program.
- Author
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Lira, J. P. E., Barelli, M. A. A., da Silva, V. P., Felipin-Azevedo, R., dos Santos, D. T., Galbiati, C., de Sá, R. O., and Poletine, J. P.
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GENETIC variation , *CROP improvement , *PLANT germplasm , *OILSEED plants , *ANIMAL feeds - Abstract
Safflower, Carthamus tinctorius (Asteraceae), is an oilseed plant with good adaptability to warm and dry climatic conditions. It is used for biodiesel production, human food, animal feed, and in the pharmaceutical industry. Recently, the crop has been highlighted, mainly for its oil quality and for biofuel production. We compared 124 safflower genotypes, which are a part of the State University of Mato Grosso germplasm collection, based on their agronomic characteristics, to provide the initial guidelines for a breeding program. Evaluations were carried out during the crop cycle and parameters were defined according to the descriptions recommended by International Board for Plant Genetic Resources and by the Ministry of Agriculture, Livestock and Supply. Multivariate analysis was used to assess the divergence among genotypes, by using Average Euclidean Distance, which ranged from 0.07 to 0.57, showing considerable genetic diversity among safflower genotypes for the agronomic characteristics that were evaluated (flowering, plant cycle, number of branches per plant, plant height, number of chapters per plant, number of seeds per chapter, chapter diameter, stem diameter, weight of 100 seeds, seed size and plant yield. Tocher and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) clustering methods were partially consistent in ordering similar genotypes. The agronomic characteristics: plant yield, number of chapters per plant and plant height provided the greatest contribution to genetic divergence among the genotypes. According to the groupings established with each methodology and depending on the variation structures within each group, several genotypes stood out in terms of agronomic performance and may be indicated for future crosses aiming to obtain improved safflower cultivars for Brazil. [ABSTRACT FROM AUTHOR]
- Published
- 2021
10. Morphological and molecular data on Phyllodistomum (Digenea: Gorgoderidae) from Brazil, with the description of a new species parasitizing Hoplias malabaricus (Bloch, 1794) (Osteichthyes, Erythrinidae).
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Dias KGA, Pérez-Ponce de León G, da Silva RJ, Vieira DHMD, Leite LAR, de Azevedo RK, and Abdallah VD
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- Animals, Female, Brazil, Phylogeny, Body Size, RNA, Ribosomal, 28S genetics, Characiformes, Trematoda genetics
- Abstract
Phyllodistomum pepirense n. sp. is described from the urinary bladder of Hoplias malabaricus (Bloch, 1794), sampled in the Jacaré-Pepira River in São Paulo state, Brazil. The isolates of the new species were recovered as a monophyletic group in the phylogenetic analysis of the 28S rRNA gene, which showed the new species as the sister taxa of Phyllodistomum virmantasi Pinacho-Pinacho, Sereno-Uribe, Hernández-Orts, García-Varela & Pérez-Ponce de León, 2021, a species sampled from an eleotrid fish in Southeastern Mexico. The new species differs morphologically from P. virmantasi by having a larger body size, slightly lobed testes and ovary, a mostly intercaecal uterus, slightly diverticulated caeca, and vitelline masses irregularly shaped. The new species is also readily distinguished from other species of Phyllodistomum Braun, 1899 reported from freshwater fishes in Brazil - namely, P. rhamdiae Amato & Amato, 1993 and P. spatula Odhner, 1902. The new species is herein described based on morphological characteristics, molecular data from D1-D3 domains of the 28S rRNA gene, host association, and geographical distribution.
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- 2023
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11. Seasonal patterns of infestation by monogenean parasites of fish and their relationship with water parameters in two rivers with different disturbance gradients in southeastern Brazil.
- Author
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Leite LAR, Januário FF, Pelegrini LS, Antoniassi B, Azevedo RK, and Abdallah VD
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- Animals, Rivers parasitology, Seasons, Water, Brazil, Nitrates, Parasites, Cichlids, Fish Diseases epidemiology, Fish Diseases parasitology
- Abstract
Here, we evaluate the relationships between the infestation rates of five monogenean parasites species with the dry and wet seasons, with the organic and inorganic parameters of the water of two rivers: the Jacaré-Pepira and Jacaré-Guaçú, and with the condition factors of its fish hosts: Serrasalmus maculatus and Astronotus crassipinnis, in the state of São Paulo, southeastern Brazil. Fish were collected between January and December 2017. Anacanthorus serrasalmi, Amphithecium speirocamarotum and Gussevia asota had higher abundance rates (Student's t test, p ≤ 0.05) in the wet season. Gussevia asota had its abundance negatively correlated to nitrate in the Jacaré-Pepira River and with total nitrogen and potassium in the Jacaré-Guaçú River. Regarding the fish hosts condition factors, was observed a positive correlation with the abundances of G. asota in the Jacaré-Guaçú River, and with A. serrasalmi in the Jacaré-Pepira River. In general, wet season favored an increasing in the infestation rates of the monogeneans parasites in their host species, mainly in the river considered as the most polluted, the Jacaré-Guaçú River. Of the five parasites species analyzed in this study, only Gussevia astronoti and Rhinoxenus piranhus had no interaction with seasonality, river water variables, or fish host condition factors. On the other hand, G. asota had interactions both with water parameters (nitrate and total nitrogen) and with the hosts condition factors, which reflected in the abundance and intensity rates, showing itself as a species sensitive to changes in the environment and, therefore, that can be considered as a bioindicator organism.
- Published
- 2023
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12. Completeness of tuberculosis information system data from prisoners in the state Rio Grande do Sul, Brazil.
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Busatto C, Jarczewski CA, Dotta RM, Ely KZ, Silva PEAD, Ramis IB, and Possuelo LG
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- Humans, Brazil epidemiology, Cross-Sectional Studies, Information Systems, Tuberculosis drug therapy, Tuberculosis epidemiology, Prisoners
- Abstract
Tuberculosis (TB) has a high incidence in several countries and is even more severe in prisoners. We evaluated the completeness of prisoners TB notifications in the Notifiable Disease Information System (SINAN) carried out by prison primary care teams (eAPP) or by other health facilities in the state of Rio Grande do Sul (RS). This descriptive cross-sectional study used prisoners data notifications in the SINAN TB by the eAPP or other health facilities from January 2014 to November 2018. We analyzed the percentage of completeness of the variables: gender, ethnicity, schooling, HIV, entry type, sputum smear, sputum culture, AIDS, ART during TB treatment, directly observed treatment (DOT), sixth-month smear, and closure status. Around 52.9% of TB cases in prisoners were reported by eAPP, and other health facilities reported 47.1% of the cases. Eighty percent of the variables were classified in category 4 (75.1% to 100% completeness). However, the DOT and sixth-month smear variables were classified into category 3 (50.1% and 75% completeness). While it does not compromise the notification of TB in the SINAN, the lack of data can impair the quality of information about the disease.
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- 2022
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13. Patterns of distribution and accumulation of trace metals in Hysterothylacium sp. (Nematoda), Phyllodistomum sp. (Digenea) and in its fish host Hoplias malabaricus, from two neotropical rivers in southeastern Brazil.
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Rosa Leite LA, Dos Reis Pedreira Filho W, Kozlowiski de Azevedo R, and Doro Abdallah V
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- Animals, Brazil, Environmental Monitoring, Rivers, Characiformes, Metals, Heavy analysis, Nematoda, Trematoda, Water Pollutants, Chemical analysis
- Abstract
Here we evaluated the potential for trace metal accumulation of two parasitic species, Hysterothylacium sp. (Nematoda) and Phyllodistomum sp. (Digenea), found parasitizing Hoplias malabaricus, a characiform fish also known as trahira, collected from two neotropical rivers, Jacaré-Pepira and Jacaré-Guaçú, in southeastern Brazil. Fish were collected between July 2017 and July 2019, totaling 90 fish specimens analyzed, 45 from each river. From fish, we take samples of three different tissues: muscle, intestine and liver. Along with the parasite samples taken from fish hosts, tissue samples were analyzed by an Inductively Coupled Plasma Mass Spectrometer (ICP-MS) for obtaining the trace metal (Al, Cr, Mn, Fe, Ni, Cu, As, Cd e Pb) concentrations. All elements were found in statistically higher concentrations in the parasites, both nematodes and digeneans, than in the host tissues, but in comparison, was observed that Hysterothylacium sp. had higher concentrations than those obtained in Phyllodistomum sp. We also found that uninfected fish had statistically higher concentrations of metals than infected ones. And in those who are infected, the size of the parasitic infrapopulations correlated negatively with the concentrations of trace metals obtained in the hosts tissues, that is, the concentrations in fish showed a tendency to decrease as the parasitic infrapopulations increased, or vice versa. In addition, our results show that the influence of the parasitic infrapopulations on metal concentrations in the fish host is not affected in cases of mono-infection or co-infection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2021
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14. Viral metagenomics in blood donors with post-donation diseases and negative tests for dengue and Zika viruses RNA detection during a major outbreak of arboviruses in Sao Paulo State in 2016.
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Bezerra RDS, Peronni KC, Barros BDF, Oliveira LS, Rodrigues ES, Azevedo R, Ubiali EMA, Covas DT, Kashima S, and Slavov SN
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- Arboviruses, Brazil, Dengue diagnosis, Dengue epidemiology, Disease Outbreaks, Humans, RNA, Viral genetics, Zika Virus Infection diagnosis, Zika Virus Infection epidemiology, Blood Donors, Metagenomics, RNA, Viral blood, Zika Virus genetics
- Published
- 2020
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15. A new species of Creptotrematina (Trematoda: Allocreadiidae) from characid fishes of Brazil: morphological and molecular data.
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Alves Dias KG, Pérez-Ponce de León G, de Almeida Camargo A, Müller MI, da Silva RJ, Kozlowiski de Azevedo R, and Abdallah VD
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- Animals, Brazil, DNA, Helminth isolation & purification, Female, Phylogeny, RNA, Ribosomal, 28S genetics, Rivers, Trematoda isolation & purification, Trematode Infections parasitology, Characidae parasitology, Fish Diseases parasitology, Trematoda anatomy & histology, Trematoda classification, Trematode Infections veterinary
- Abstract
A new species of Creptotrematina Yamaguti, 1954 was collected from characid fishes, Astyanax fasciatus (Cuvier, 1819) and Astyanax lacustris Lucerna & Soares, 2016 from the Batalha River in the State of Sao Paulo, Brazil. The new species most closely resembles Creptotrematina aguirrepequenoi, but differs by the elongated shape of vitelline follicles, the extension of these follicles in the posterior end of body and the fact that they are not confluent. The morphological differences were confirmed through molecular data. Three specimens were sequenced, and molecular analyses were based on the internal transcribed spacers 2 and D1-D3 domains of the 28S ribosomal RNA gene. The obtained topologies showed the new species as a sister taxon of C. aguirrepequenoi, a species originally described from Astyanax mexicanus in Mexico, and later found in Astyanax aeneus in Costa Rica. Isolates of the new species are reciprocally monophyletic, and genetic distance values are similar to those observed in other species pairs within Allocreadiidae. These findings corroborate that the genus Creptotrematina is mostly a parasite of characids, and widely extended across the Americas, with representative species occurring between Argentina and northern Mexico.
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- 2020
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16. Skin nodules associated with parasitism with Henneguya sp. (Cnidaria: Myxosporea) in the neotropical fish Cyphocharax modestus.
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Mirandola Dias Vieira DH, Abdallah VD, José da Silva R, and Kozlowiski de Azevedo R
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- Animals, Brazil, Myxozoa anatomy & histology, Myxozoa cytology, Parasitic Diseases, Animal pathology, Phylogeny, Rivers, Seafood parasitology, Species Specificity, Spores, Subcutaneous Tissue parasitology, Subcutaneous Tissue pathology, Characiformes parasitology, Fishes parasitology, Myxozoa isolation & purification, Myxozoa pathogenicity, Parasitic Diseases, Animal parasitology, Skin parasitology, Symbiosis
- Abstract
A new myxozoan species, Henneguya sp., is described based on material from skin of Cyphocharax modestus. Mature myxospores are were elongate and ellipsoidal, measuring 21.4 ± 1.2 (19.4-23.2) μm in total length, 5.1 ± 0.3 (4.5-5.8) μm in width, 11.9 ± 0.5 (10.9-12.7) μm in body length and 9.6 ± 0.7 (8.4-10.5) μm in length of the caudal process. The polar capsules were elongated and had unequal sizes, with length of 5.1 ± 0.4 (4.5-6.0) μm and 5.6 ± 0.4 (4.9-6.3) μm for smaller and larger respectively and width of 1.8 ± 0.2 (1.4-2.0) μm. The larger polar capsule had 8 turns in polar filament while the smaller polar capsule had 5 turns in polar filament. The macroscopic analysis revealed the presence of large nodules, which were located before and after the dorsal fin of the hosts. The histopathological analysis showed the development of nodules filled with plasmodia, surrounded by loose connective tissue, developed in the dermis of the skin. Many cysts containing countless spores, as well as free spores, were located in the dermis and hypodermis of the hosts, causing the disorganization of the connective tissue that is responsible for the support. This is the first record of a Henneguya species in C. modestus., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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17. Prevalence of cocaine and derivatives in blood and urine samples of trauma patients and correlation with injury severity: a prospective observational study.
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Oliveira KD, Fraga GP, Baracat ECE, Morcillo AM, Lanaro R, Costa JL, Capitani EM, Bucaretchi F, Ferreira Filho AI, Gimenes VC, and de Azevedo RCS
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- Adolescent, Adult, Aged, Aged, 80 and over, Brazil, Cross-Sectional Studies, Female, Humans, Longitudinal Studies, Male, Middle Aged, Prospective Studies, Risk Factors, Trauma Severity Indices, Cocaine blood, Cocaine urine, Substance Abuse Detection methods, Wounds and Injuries blood, Wounds and Injuries urine
- Abstract
Purpose: The abuse of cocaine and its derivatives presents a likely risk factor for injury. Trauma incurred by cocaine and derivative abusers may be more severe than that incurred by non-users., Objectives: To ascertain the presence of cocaine and its derivatives in trauma patients and to correlate RTS (Revised Trauma Score) and ISS (Injury Severity Score) with the presence of cocaine and its derivatives in blood and urine samples., Methods: All trauma victims treated in an emergency unit between November 11, 2012 and September 15, 2013 were included in the study. Blood and urine samples were collected on admission to hospital. RTS and ISS scores were then compared with the presence or absence of cocaine and its derivatives in the samples. The associations between RTS < 7.84 and ISS > 16 and the independent variables were evaluated by the gross odds ratio values, determined by univariate logistic regression. Multivariate analysis was performed using multivariate logistic regression., Results: Of 453 patients (83.7% male) included in the study, 28.6% presented ISS > 16 and 33.6% presented RTS < 7.84. A total of 435 samples were collected, and 86 (19.8%) provided positive samples for cocaine, 48 (11%) for crack and 69 (15.9%) for cocaethylene. Compared to other patients, drug users showed a greater probability of RTS < 7.84 (2.18 times greater) and a greater probability of ISS > 16 (1.76 times greater)., Conclusion: For the trauma patients included in our study, the use of cocaine and its derivatives was shown to be associated with more severe traumas, as demonstrated by their RTS and ISS scores.
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- 2019
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18. Genomic characterization and evolution of Tacaiuma orthobunyavirus (Peribunyaviridae family) isolated in Brazil.
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de Melo AB Junior, de Souza WM, Acrani GO, Carvalho VL, Romeiro MF, Tolardo AL, da Silva SP, Cardoso JF, de Oliveira Chiang J, da Silva Gonçalves Vianez JL Júnior, do Socorro da Silva Azevedo R, Figueiredo LTM, da Costa Vasconcelos PF, Nunes MRT, and de Almeida Medeiros DB
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- Animals, Brazil, Bunyaviridae Infections virology, Chlorocebus aethiops, Evolution, Molecular, Genome, Viral genetics, Humans, Phylogeny, RNA, Viral analysis, RNA, Viral genetics, Vero Cells, Orthobunyavirus classification, Orthobunyavirus genetics
- Abstract
Tacaiuma virus (TCMV) is antigenically characterized as a member of the Anopheles A complex in the Orthobunyavirus genus, Peribunyaviridae family (Bunyavirales order). Clinically, the TCMV infection is characterized by acute febrile illness with myalgia and arthralgia lasting three to five days. However, the genomic and evolutionary aspect of this virus has not been elucidated. In this study, we described the complete coding sequences of three segments of two TCMV strains isolated in Brazil and three complete coding sequences of the small segment of three TCMV strains. All the strains sequenced in this study showed the typical genomic organization of orthobunyaviruses that infect vertebrates, except for the absence of the open reading frame that encodes the well-described non-structural small protein. This study presents the genomic and evolutionary characterization of TCMV strains and would be helpful for diagnostic purposes and epidemiology., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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19. Hybrid sterility in crosses between two Brazilian sibling species of the Anopheles albitarsis complex.
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Fontoura NG, Araki AS, Van Der Maas Azevedo R, Galardo AK, Peixoto AA, and Lima JB
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- Animals, Brazil, Female, Hybridization, Genetic, Inbreeding, Infertility, Male, Molecular Sequence Data, Sequence Analysis, DNA, Sex Ratio, Survival Analysis, Anopheles physiology, Chimera
- Abstract
Background: Complexes of cryptic species are common in several taxa and this is also the case in the Anopheles genus, a group including all known human malaria vectors. The Anopheles albitarsis complex comprises at least nine cryptic species, some of which are implicated as vectors of human malaria. Several different types of data have been generated for this species complex such as cytogenetics, alloenzymes, morphological and feeding behavioral, hybridization experiments, RAPD-PCR and RFLP and mitochondrial and nuclear markers. Studies focused on its postzygotic isolation are still somewhat rare in the literature despite their importance to understand the speciation process and the level of gene flow potentially occurring among the different sibling species., Methods: Hybridization experiments between Anopheles albitarsis s.s. and Anopheles marajoara, as well as backcrosses between hybrids and Anopheles albitarsis s.s., were performed using the induced mating technique. Results were compared to intraspecific crosses. Larva-to-adult viability and sex ratio were also assessed., Results: Male hybrids show very low insemination rates and nearly complete sterility, apparently due to abnormalities in their reproductive organs. Evidence of partial sterility among the hybrid females was also observed., Conclusions: Our data indicated that Anopheles albitarsis s.s. and Anopheles marajoara show a high level of postzygotic isolation with a strong hybrid male sterility. This result is consistent with the Haldane's rule which states that in interspecific crosses the heterogametic sex is the first to be affected. However, the fact that the females are not completely sterile raises the possibility of introgression between these two siblings species.
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- 2014
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20. Functional capacity after pediatric liver transplantation: a pilot study.
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Maria da Silva R, Brunow de Carvalho W, Johnston C, Borba de Castro M, Manta Ferreira I, Patti CL, Anthero de Azevedo R, Miziara Gonzalez A, Moura Linhares M, and Augusto Salzedas-Netto A
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- Adolescent, Anthropometry, Brazil, Child, Cross-Sectional Studies, Exercise Test, Female, Humans, Male, Pilot Projects, Prospective Studies, Reproducibility of Results, Respiratory Function Tests, Liver Transplantation, Physical Fitness, Walking physiology
- Abstract
The prospective cross-sectional study investigated the 6MWT performance in pediatric group of liver transplant recipients (6-17 yr, median post-transplantation time of 22 months) and compared to the normal values obtained in healthy children as well as evaluated the reproducibility of the 6MWT. We analyzed the relationship between walked distance and the 6MWw, distance walked × body weight) with the anthropometric, clinical, and pulmonary functions. In post-transplanted group, the average walked distance was significantly shorter compared with control (687 ± 80 m vs. 511 ± 72 m, p < 0.001). The calculated ICC coefficient confirmed the reproducibility among tests. The Pearson correlation revealed that only walked distance in the 6MWT was moderately correlated with tidal volume. Conversely, the 6MWw was significantly correlated with age, weight, height, BMI, FVC, PEF rate, and volume expiratory. According to multiple regression analysis, age, VE and FVC factors explained 80% of the variance in the 6MWw. In conclusion, the pediatric liver transplant recipients' performance in the 6MWT is significantly lower than the values for healthy children of the same age. Notably, the 6MWw may provide relevant information, constituting an additional parameter in the determination of functional capacity., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2014
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21. Analysis of transmitted resistance to raltegravir and selective pressure among HIV-1-infected patients on a failing HAART in Sao Paulo, Brazil.
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Mantovani NP, Azevedo RG, Rabelato JT, Sanabani S, Diaz RS, and Komninakis SV
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- Amino Acid Sequence, Brazil epidemiology, Female, HIV Infections epidemiology, HIV Infections virology, HIV Integrase genetics, HIV-1 isolation & purification, Humans, Male, Molecular Sequence Data, Phylogeny, Polymorphism, Genetic, Raltegravir Potassium, Sequence Homology, Amino Acid, Treatment Failure, Anti-HIV Agents pharmacology, Antiretroviral Therapy, Highly Active methods, Drug Resistance, Viral, HIV Infections transmission, HIV-1 drug effects, Pyrrolidinones pharmacology, Selection, Genetic
- Abstract
We studied the presence of primary resistance to raltegravir (RAL), natural polymorphisms, and selection pressure on HIV-1 integrase. We found a high frequency of integrase polymorphisms related to the resistance to RAL and sequence stability. Further studies are needed to determine the importance of these polymorphisms to RAL resistance.
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- 2012
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22. HTLV-1/2 seroprevalence and coinfection rate in Brazilian first-time blood donors: an 11-year follow-up.
- Author
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Pinto MT, Rodrigues ES, Malta TM, Azevedo R, Takayanagui OM, Valente VB, Ubiali EM, Covas DT, and Kashima S
- Subjects
- Adolescent, Adult, Brazil epidemiology, Coinfection diagnosis, HTLV-I Infections diagnosis, HTLV-II Infections diagnosis, Human T-lymphotropic virus 1 genetics, Human T-lymphotropic virus 1 immunology, Human T-lymphotropic virus 2 genetics, Human T-lymphotropic virus 2 immunology, Humans, Immunoenzyme Techniques, Middle Aged, Polymerase Chain Reaction, Seroepidemiologic Studies, Young Adult, Blood Donors statistics & numerical data, Coinfection epidemiology, HTLV-I Infections epidemiology, HTLV-II Infections epidemiology
- Abstract
The seroprevalence and geographic distribution of HTLV-1/2 among blood donors are extremely important to transfusion services. We evaluated the seroprevalence of HTLV-1/2 infection among first-time blood donor candidates in Ribeirão Preto city and region. From January 2000 to December 2010, 1,038,489 blood donations were obtained and 301,470 were first-time blood donations. All samples were screened with serological tests for HTLV-1/2 using enzyme immunoassay (EIA). In addition, the frequency of coinfection with hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), Chagas disease (CD) and syphilis was also determined. In-house PCR was used as confirmatory test for HTLV-1/2. A total of 296 (0.1%) first-time donors were serologically reactive for HTLV-1/2. Confirmatory PCR of 63 samples showed that 28 were HTLV-1 positive, 13 HTLV-2 positive, 19 negative and three indeterminate. Regarding HTLV coinfection rates, the most prevalent was with HBV (51.3%) and HCV (35.9%), but coinfection with HIV, CD and syphilis was also detected. The real number of HTLV-infected individual and coinfection rate in the population is underestimated and epidemiological studies like ours are very informative.
- Published
- 2012
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23. Modelling immunization strategies with cytomegalovirus vaccine candidates.
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Azevedo RS and Amaku M
- Subjects
- Adolescent, Adult, Age Factors, Brazil epidemiology, Child, Computer Simulation, Cytomegalovirus Infections congenital, Cytomegalovirus Infections epidemiology, Cytomegalovirus Infections transmission, Humans, Infant, Seroepidemiologic Studies, Young Adult, Cytomegalovirus Infections prevention & control, Cytomegalovirus Vaccines immunology, Models, Immunological
- Abstract
In order to analyse the impact of vaccination against cytomegalovirus (CMV) on congenital infection incidence using current vaccines tested in phase II clinical trials, we simulated different scenarios by mathematical modelling, departing from the current vaccine characteristics, varying age at vaccination, immunity waning, vaccine efficacy and mixing patterns. Our results indicated that the optimal age for a single vaccination interval is from 2 to 6 months if there is no immunity waning. Congenital infection may increase if vaccine-induced immunity wanes before 20 years. Congenital disease should increase further when the mixing pattern includes transmission among children with a short duration of protection vaccine. Thus, the best vaccination strategy is a combined schedule: before age 1 year plus a second dose at 10-11 years. For CMV vaccines with low efficacy, such as the current ones, universal vaccination against CMV should be considered for infants and teenagers.
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- 2011
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24. Ground-foraging ants (Hymenoptera: Formicidae) and rainfall effect on pitfall trapping in a deciduous thorn woodland (caatinga), Northeastern Brazil.
- Author
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Nunes FA, Segundo GB, Vasconcelos YB, Azevedo R, and Quinet Y
- Subjects
- Animals, Brazil, Population Density, Population Dynamics, Rain, Seasons, Ants physiology, Feeding Behavior physiology
- Abstract
The semi-arid Caatinga is the fourth largest biome of Brazil, which biota still remains one of the most poorly known, especially with regard to invertebrate groups. In this study, a ground-foraging ant assemblage was surveyed during one year and the effect of rainfall on pitfall trapping was assessed. The study was performed in an area located in the municipality of Pentecoste (3 degrees 48' S - 39 degrees 20' W), in the State of Ceará. A 200m transect with 20 equidistant sampling points was established. Transect sampling was performed once a month during 12 months, over the period August 2008-August 2009. At each sampling point, a pitfall trap partially filled with a mixture of ethanol and monoethylene glycol was placed at the beginning of each month and remained in the field for seven days. 39 species belonging to six subfamilies and 19 genera, plus two unidentified species, were collected, with Pheidole (10 spp.) and Camponotus (8 spp.) being the taxa with the most species. 23 species were frequent, being found in more than 50% of the 12 transect samplings. Five species had an intermediate frequency (25 to 50%), while 13 were relatively infrequent (less than 25%). Most of the species (22) showed low occurrence, being found in less than 10% of the 240 samples (20 samples each month, during 12 months). Only five species were collected in more than 50% of the samples, those species being also responsible for most of the total abundance (number of captured individuals of all species) observed each month. The species-accumulation curves (observed and estimated) indicated that sampling sufficiency was attained, and that about 92% of the estimated ground-foraging ant fauna had been collected. 40 and 29 species were collected in the dry and rainy season, respectively, with monthly species richness ranging from 13 to 28. The total ant abundance showed a drastic decrease during the rainy season, and a negative linear correlation was found between rainfall and total ant abundance (R2 = 0.68). A similar negative linear correlation was found for species occurrences against rainfall (R2 = 0.71), and for mean number of species per pitfall trap against rainfall (R2 = 0.71). However, some species showed equal abundance, occurrence and mean number of individuals per pitfall trap in both seasons, while others showed a much higher abundance and occurrence during the rainy season. Pitfall trapping as a method to sample ground-foraging ant assemblage of the Caatinga biome and potential factors responsible for lower pitfall trap performance during rainy season are discussed.
- Published
- 2011
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25. Dengue virus serotype 4, Roraima State, Brazil.
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Temporao JG, Penna GO, Carmo EH, Coelho GE, do Socorro Silva Azevedo R, Teixeira Nunes MR, and da Costa Vasconcelos PF
- Subjects
- Adolescent, Adult, Brazil epidemiology, Child, Dengue diagnosis, Dengue Virus classification, Dengue Virus genetics, Female, Humans, Male, Middle Aged, Phylogeny, RNA, Viral genetics, Serotyping, Viral Envelope Proteins genetics, Young Adult, Dengue epidemiology, Dengue virology, Dengue Virus physiology, Disease Outbreaks
- Published
- 2011
- Full Text
- View/download PDF
26. Expanded description of Dolops bidentata (Bouvier, 1899) (Branchiura: Argulidae) based on specimens collected on Pygocentrus nattereri Kner, 1858 (Characiformes) from Poconé Wetland, MT, Brazil.
- Author
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Silva-Souza AT, Abdallah VD, de Azevedo RK, da Silva FA, and Luque JL
- Subjects
- Animals, Brazil, Female, Male, Microscopy, Electron, Scanning, Arguloida anatomy & histology, Arguloida classification, Arguloida ultrastructure, Fishes parasitology
- Abstract
The current information on the branchiuran Dolops bidentata, a species described more one hundred years ago, is valid but incomplete; hence, an expanded description is given herein. Additional morphological information was obtained by light and scanning electron microscopy from specimens collected on Pygocentrus nattereri from the Poconé Wetland, MT, Brazil. Description of the appendages and other structures such as respiratory area, mouth, details and ornamentation of antennules and maxillae are provided for the first time.
- Published
- 2011
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27. The invasion route for an insect pest species: the tobacco aphid in the New World.
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Zepeda-Paulo FA, Simon JC, Ramírez CC, Fuentes-Contreras E, Margaritopoulos JT, Wilson AC, Sorenson CE, Briones LM, Azevedo R, Ohashi DV, Lacroix C, Glais L, and Figueroa CC
- Subjects
- Animals, Argentina, Bayes Theorem, Brazil, Chile, Founder Effect, France, Genotype, Greece, Microsatellite Repeats, Models, Biological, Multilocus Sequence Typing, Sequence Analysis, DNA, United States, Aphids genetics, Genetic Variation, Genetics, Population, Introduced Species
- Abstract
Biological invasions are rapid evolutionary events in which populations are usually subject to a founder event during introduction followed by rapid adaptation to the new environment. Molecular tools and Bayesian approaches have shown their utility in exploring different evolutionary scenarios regarding the invasion routes of introduced species. We examined the situation for the tobacco aphid, Myzus persicae nicotianae, a recently introduced aphid species in Chile. Using seven microsatellite loci and approximate Bayesian computation, we studied populations of the tobacco aphid sampled from several American and European countries, identifying the most likely source populations and tracking the route of introduction to Chile. Our population genetic data are consistent with available historical information, pointing to an introduction route of the tobacco aphid from Europe and/or from other putative populations (e.g. Asia) with subsequent introduction through North America to South America. Evidence of multiple introductions to North America from different genetic pools, with successive loss of genetic diversity from Europe towards North America and a strong bottleneck during the southward introduction to South America, was also found. Additionally, we examined the special case of a widespread multilocus genotype that was found in all American countries examined. This case provides further evidence for the existence of highly successful genotypes or 'superclones' in asexually reproducing organisms., (© 2010 Blackwell Publishing Ltd.)
- Published
- 2010
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28. Frequency distribution of XbaIG > T and HaeIIIT > C GLUT1 polymorphisms among different Brazilian ethnic groups.
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Costa GC, Alcantara LC, Azevedo R, Muricy G, Kashima SH, Covas DT, Galvão-Castro B, and Gadelha SR
- Subjects
- Brazil, Genotype, Humans, Deoxyribonucleases, Type II Site-Specific metabolism, Ethnicity genetics, Gene Frequency genetics, Glucose Transporter Type 1 genetics, Polymorphism, Single Nucleotide genetics
- Abstract
GLUT is the major glucose transporter in mammalian cells. Single nucleotide polymorphisms (SNP) at GLUT1 promoter and regulatory regions have been associated to the risk of developing nephropathy in different type 1 and type 2 diabetic populations. It has been demonstrated that differences in allelic and genotypic frequencies of GLUT1 gene (SLC2A1) polymorphisms occur among different populations. Therefore, ethnic differences in distribution of GLUT1 gene polymorphisms may be an important factor in determining gene-disease association. In this study, we investigated the XbaIG > T and HaeIIIT > C polymorphisms in six different Brazilian populations: 102 individuals from Salvador population (Northern Brazil), 56 European descendants from Joinville (South Brazil), 85 Indians from Tiryió tribe (North Brazil) and 127 samples from Southern Brazil: 44 from European descendants, 42 from African descendants and 41 from Japanese descendants. Genotype frequencies from both sites did not differ significantly from those expected under the Hardy-Weinberg equilibrium. We verified that the allele frequencies of both polymorphisms were heterogeneous in these six Brazilian ethnic groups.
- Published
- 2010
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29. DC-SIGN (CD209) gene promoter polymorphisms in a Brazilian population and their association with human T-cell lymphotropic virus type 1 infection.
- Author
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Kashima S, Rodrigues ES, Azevedo R, da Cruz Castelli E, Mendes-Junior CT, Yoshioka FKN, da Silva IT, Takayanagui OM, and Covas DT
- Subjects
- Adult, Aged, Brazil epidemiology, Brazil ethnology, Cell Adhesion Molecules metabolism, Female, Genetic Predisposition to Disease, Humans, Lectins, C-Type metabolism, Male, Middle Aged, Racial Groups classification, Receptors, Cell Surface metabolism, Young Adult, Cell Adhesion Molecules genetics, HTLV-I Infections epidemiology, HTLV-I Infections ethnology, HTLV-I Infections genetics, Human T-lymphotropic virus 1 pathogenicity, Lectins, C-Type genetics, Polymorphism, Single Nucleotide, Promoter Regions, Genetic genetics, Racial Groups genetics, Receptors, Cell Surface genetics
- Abstract
This study evaluated four polymorphisms located in the DC-SIGN (CD209) gene promoter region (positions -336, -332 -201 and -139) in DNA samples from four Brazilian ethnic groups (Caucasians, Afro-Brazilian, Asians and Amerindians) to establish the population distribution of these single-nucleotide polymorphisms (SNPs) and correlated DC-SIGN polymorphisms and infection in samples from human T-cell lymphotropic virus type 1 (HTLV-1)-infected individuals. To identify CD209 SNPs, 452 bp of the CD209 promoter region were sequenced and the genotype and allelic frequencies were evaluated. This is the first study to show genetic polymorphism in the CD209 gene in distinct Brazilian ethnic groups with the distribution of allelic and genotypic frequency. The results showed that -336A and -139A SNPs were quite common in Asians and that the -201T allele was not observed in Caucasians, Asians or Amerindians. No significant differences were observed between individuals with HTLV-1 disease and asymptomatic patients. However, the -336A variant was more frequent in HTLV-1-infected patients [HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), 80 %; healthy asymptomatic HTLV-1 carriers, 90 %] than in the control group (70 %) [P=0.0197, odds ratio (OR)=2.511, 95 % confidence interval (CI)=1.218-5.179). In addition, the -139A allele was found to be associated with protection against HTLV-1 infection (P=0.0037, OR=0.3758, 95 % CI=0.1954-0.7229) when the HTLV-1-infected patients as a whole were compared with the healthy-control group. These observations suggest that the -139A allele may be associated with HTLV-1 infection, although no significant association was observed among asymptomatic and HAM/TSP patients. In conclusion, the variation observed in SNPs -336 and -139 indicates that this lectin may be of crucial importance in the susceptibility/transmission of HTLV-1 infections.
- Published
- 2009
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30. Polymorphisms at GLUT1 gene are not associated with the development of TSP/HAM in Brazilian HTLV-1 infected individuals and the discovery of a new polymorphism at GLUT1 gene.
- Author
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Costa GC, Azevedo R, Gadelha SR, Kashima SH, Muricy G, Olavarria VN, Covas DT, Takayanagui OM, Galvão-Castro B, and Alcantara LC
- Subjects
- Brazil epidemiology, Gene Frequency, Genotype, HTLV-I Infections epidemiology, Human T-lymphotropic virus 1 genetics, Human T-lymphotropic virus 1 isolation & purification, Humans, Paraparesis, Tropical Spastic epidemiology, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, Proviruses genetics, Proviruses isolation & purification, Glucose Transporter Type 1 genetics, HTLV-I Infections genetics, Paraparesis, Tropical Spastic genetics, Polymorphism, Genetic
- Abstract
The development of HTLV-1 associated clinical manifestations, such as TSP/HAM and ATLL, occur in 2-4% of the infected population and it is still unclear why this infection remains asymptomatic in most infected carriers. Recently, it has been demonstrated that HTLV uses the Glucose transporter type 1 (GLUT1) to infect T-CD4(+) lymphocytes and that single nucleotide polymorphisms (SNP) in the GLUT1 gene are associated with diabetic nephropathy in patients with diabetes mellitus in different populations. These polymorphisms could contribute to a higher GLUT1 protein expression on cellular membrane, facilitating the entry of HTLV and its transmission cell by cell. This could result in a higher provirus load and consequently in the development of TSP/HAM. To evaluate the role of GLUT1 gene polymorphisms in the development of TSP/HAM in HTLV-1 infected individuals, the g.22999G > T, g.15339T > C and c.-2841A > T sites were analyzed by PCR/RFLP or sequencing in 244 infected individuals and 102 normal controls. The proviral load of the HTLV-1 infected patients was also analyzed using Real Time Quantitative PCR. Genotypic and allelic frequencies of the three sites did not differ significantly between controls and HTLV-1 infected individuals. There was no difference in genotypic and allelic distributions among patients as to the presence or absence of HTLV-1 associated clinic manifestations. As regards the quantification of the provirus load, we observed a significant reduction in the asymptomatic individuals compared with the oligosymptomatic and TSP/HAM individuals. These results suggest that g.22999G > T, g.15339T > C, and c.-2841A > T SNP do not contribute to HTLV-1 infection nor to the genetic susceptibility of TSP/HAM in Brazilian HTLV-1 infected individuals., (Copyright 2009 Wiley-Liss, Inc.)
- Published
- 2009
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31. Cost-effectiveness analysis of universal childhood vaccination against varicella in Brazil.
- Author
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Valentim J, Sartori AM, de Soárez PC, Amaku M, Azevedo RS, and Novaes HM
- Subjects
- Adolescent, Adult, Algorithms, Brazil epidemiology, Chickenpox Vaccine therapeutic use, Child, Child, Preschool, Cost of Illness, Cost-Benefit Analysis, Health Care Costs, Hospitalization economics, Hospitalization statistics & numerical data, Humans, Infant, Models, Economic, Models, Statistical, Transportation of Patients economics, Young Adult, Chickenpox epidemiology, Chickenpox prevention & control, Chickenpox Vaccine economics, Immunization Programs economics, Mass Vaccination economics
- Abstract
This study conducts a cost-effectiveness analysis of a childhood universal varicella vaccination program in Brazil. An age and time-dependent dynamic model was developed to estimate the incidence of varicella for 30 years. Assuming a single-dose schedule; vaccine efficacy of 85% and coverage of 80%, the program could prevent 74,422,058 cases and 2905 deaths. It would cost R$ 3,178,396,110 and save R$ 660,076,410 to the society and R$ 365,602,305 to the healthcare system. The program is cost-effective (R$ 14,749 and R$ 16,582 per life-year saved under the societal and the healthcare system's perspective, respectively). The program's cost-effectiveness is highly sensitive to the vaccine price and number of doses.
- Published
- 2008
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- View/download PDF
32. Age-specific seroprevalence to an immunodominant Cryptosporidium sporozoite antigen in a Brazilian population.
- Author
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Cox MJ, Elwin K, Massad E, and Azevedo RS
- Subjects
- Adolescent, Adult, Age Factors, Animals, Antibodies, Protozoan blood, Brazil epidemiology, Child, Child, Preschool, Cryptosporidiosis blood, Cryptosporidiosis parasitology, Cryptosporidium isolation & purification, Enzyme-Linked Immunosorbent Assay methods, Female, Humans, Infant, Infant, Newborn, Male, Predictive Value of Tests, Seroepidemiologic Studies, Urban Health, Cryptosporidiosis epidemiology, Cryptosporidium immunology, Immunoglobulin G blood
- Abstract
The seroepidemiology of Cryptosporidium infection was investigated in a representative sample of a normal population in the State of Sao Paulo, Brazil using a recombinant form of the immunodominant 27-kDa sporozoite antigen. IgG seropositivity was low in infants following loss of maternal antibody but quickly increased to approximately 60% by 5 years, then 80% by the age of 10 years, after which prevalence remained constant. The broad range of antibody concentrations is consistent with previous reports that the IgG response to C. parvum is short-lived. There is also evidence that average antibody concentrations increase with age. Results suggest that the recombinant antigen may be a more sensitive method of measuring seroprevalence than the native antigen in Western blot. Although cross-sectional studies can provide an insight into the epidemiology of C. parvum in normal populations, further studies investigating the dynamics of the humoral immune responses to Cryptosporidium and the use of serology in epidemiological studies are required.
- Published
- 2005
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33. The vulnerability of Brazilian female prisoners to HIV infection.
- Author
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Strazza L, Azevedo RS, Carvalho HB, and Massad E
- Subjects
- Brazil epidemiology, Female, HIV Infections diagnosis, Humans, Male, Risk Factors, Seroepidemiologic Studies, Surveys and Questionnaires, HIV Infections epidemiology, Prisoners
- Abstract
The purpose of the present study was to determine the vulnerability of women in prison to HIV infection. The study was carried out from August to October 2000 in a São Paulo State Penitentiary, where 299 female prisoners were serving time. We interviewed and obtained a blood sample from 290 females who agreed to enter the study. Sera were tested for the presence of antibodies to HIV, hepatitis C virus (HCV) and syphilis and the odds ratio (OR) was calculated for variables related to HIV positivity on the basis of a questionnaire. The overall prevalence data were: 13.9% for HIV (37 of 267), 22.8% for syphilis (66 of 290), and 16.2% for HCV (47 of 290). Sexual partnership variables were significantly related to HIV infection. These included HIV-positive partners (OR = 7.36, P = 0.0001), casual partners (OR = 8.96, P = 0.009), injectable drug user partners (OR = 4.7, P = 0.0001), and history of sexually transmitted disease (OR = 2.07, P = 0.05). In addition, a relationship was detected between HIV infection and drug use (OR = 2.48, P = 0.04) and injectable drug use (OR = 4.2, P = 0.002). Even women with only one partner presented a significant OR for HIV infection (OR = 2.57, P = 0.009), reflecting their vulnerability due to their trust in their partner, who did not use a condom. Although the use of injectable substances is associated with HIV infection, our results point to sexual behavior as the most important component of HIV transmission in the female prisoner population.
- Published
- 2004
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- View/download PDF
34. Varicella transmission in two samples of children with different social behaviour in the State of São Paulo, Brazil.
- Author
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Yu AL, Amaku M, Burattini MN, Massad E, and Azevedo RS
- Subjects
- Brazil epidemiology, Chickenpox epidemiology, Child, Child, Preschool, Databases, Factual, Humans, Infant, Prevalence, Social Behavior, Antibodies, Viral isolation & purification, Chickenpox transmission
- Abstract
In order to establish the differences in transmission pattern of varicella-zoster virus (VZV), a comparative seroepidemiological study was carried out in two different children samples. Children aged 1-11 years, were randomly selected from state schools of São Paulo city, Brazil. Individuals aged 1-15 years were sampled by cluster from Caieiras city. Children aged 3 years or under from Caieiras were not attending school, while those from São Paulo were attending all-day nurseries or kindergarten. The presence of antibodies to VZV was analysed by ELISA technique. The force of infection and contact rate were determined by mathematical techniques. The average age of first infection was 2.87 +/- 0.14 years and 4.07 +/- 0.47 years for Sao Paulo and Caieiras, respectively. The average force of infection estimated was 0.29 year(-1) for São Paulo and was 0.26 year(-1) for Caieiras. The proportion of seropositivity and the force of infection were higher in São Paulo school children up to 3 years of age compared with Caieiras children, where the social contact starts later. In conclusion, social changes affecting contact among children may influence varicella epidemiology.
- Published
- 2001
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35. [Prevalence of and factors associated with hepatitis B virus markers in a rural population of central Brazil].
- Author
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Souto FJ, Santo GA, Philippi JC, Pietro BR, Azevedo RB, and Gaspar AM
- Subjects
- Adolescent, Adult, Age Factors, Aged, Brazil epidemiology, Child, Child, Preschool, Cross-Sectional Studies, Female, Hepatitis B prevention & control, Hepatitis B Vaccines administration & dosage, Humans, Infant, Male, Middle Aged, Risk Factors, Hepatitis B epidemiology
- Abstract
Objective: To carry out a survey of hepatitis B virus seroepidemiology in a municipality in central Brazil, on the border of two large ecosystems, the cerrado (savanna) and the Amazon River basin., Methods: The municipality studied, Nova Mutum, is located in the north central portion of the Brazilian state of Mato Grosso. The study sample of 754 individuals included persons from families, selected at random, who were living in the municipality's urban center as well as all the individuals living in a nearby rural village. Ages ranged from 2 to 79 years. All eligible individuals were interviewed. Blood was collected and used to assess hepatitis B virus markers by enzyme-linked immunosorbent assay., Results: Hepatitis B virus infection was found in 232 individuals, or 31% of them; 19 of them (3%) were HBsAg-positive. Of the 754 persons, 149 of them (20%) who reported having been vaccinated against hepatitis B and who presented anti-HBs positivity were classified as vaccine responders. With the multivariate analysis, the variables found to be associated with exposure to hepatitis B virus were having begun sexual relations, having been vaccinated against yellow fever with a needle-free jet injection gun (for the age group < 20 years), and being an immigrant from southern Brazil (> 20 years). Vaccine coverage was low among individuals older than 10 years. The largest share of susceptible individuals (74%) were found in the age group of 11 to 20 years., Conclusions: Our data suggest that hepatitis B virus vaccine coverage in Brazil should be extended to include teenagers in populations that have a low to moderate hepatitis B virus prevalence. It is likely that our results can be extrapolated to other areas of Latin America with a similar epidemiological pattern.
- Published
- 2001
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- View/download PDF
36. Optimal age for vaccination against measles in the State of São Paulo, Brazil, taking into account the mother's serostatus.
- Author
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Zanetta RA, Amaku M, Azevedo RS, Zanetta DM, Burattini MN, and Massad E
- Subjects
- Adult, Age Factors, Antibodies, Viral biosynthesis, Antibodies, Viral immunology, Brazil, Disease Outbreaks, Female, Humans, Immunity, Maternally-Acquired, Infant, Infant, Newborn, Maternal Age, Measles epidemiology, Measles Vaccine immunology, Risk Assessment, Seroepidemiologic Studies, Urban Population, Vaccination statistics & numerical data, Antibodies, Viral blood, Immunization Programs, Immunization Schedule, Measles prevention & control, Measles Vaccine administration & dosage, Vaccination methods
- Abstract
In order to investigate if the changing levels of measles antibody in women resulting from extensive vaccination programs influence the susceptibility of children, we measured the seroprevalence of measles virus antibody of children in the first year of life and of their mothers. We compared maternal antibody decay of two groups of children: those whose mothers were 25 years old or more (mothers born in the pre-vaccination era), and less than 25 years old (mothers born in the vaccination era). Therefore, the 25-year-age cut-off was chosen to distinguish between vaccinated and non-vaccinated mothers. We also compared the immunogenicity of measles vaccine in children from 6 to 12 months of age, in these two groups and also according to their mother's serostatus. The optimal age of vaccination for a routine program was estimated by means of mathematical models. This study was carried out in a sample of 1216 mothers and their respective children. Our results indicate that the optimal age for vaccination of the whole sample was 15 months, 17 months for children born from older mothers, 14 months for children born from younger mothers, 17 months for children born from seropositive mothers and 12 months for children born from seronegative mothers. Therefore, a change to an earlier age of routine vaccination is not justified by our results.
- Published
- 2001
- Full Text
- View/download PDF
37. Cytomegalovirus seroepidemiology in an urban community of São Paulo, Brazil.
- Author
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Almeida LN, Azevedo RS, Amaku M, and Massad E
- Subjects
- Adolescent, Adult, Antibodies, Viral isolation & purification, Brazil epidemiology, Child, Child, Preschool, Cytomegalovirus Infections transmission, Female, Humans, Immunoglobulin G isolation & purification, Infant, Infant, Newborn, Retrospective Studies, Seroepidemiologic Studies, Cytomegalovirus immunology, Cytomegalovirus Infections epidemiology
- Abstract
Introduction: After the era of rubella vaccine, cytomegalovirus (CMV) infection is one of the most frequently causes of mental retardation and congenital deafness. Seroepidemiological studies are necessary to understand the transmission dynamics of the disease. The purpose of the study was to quantify the transmission rate of CMV disease in a community in the state of São Paulo, Brazil., Methods: Using ELISA test (IgG), a retrospective serological survey looking for CMV antibodies was performed in an non-immunized community. Frozen sera from 443 individuals, randomly selected by cluster sampling technique in the town of Caieiras, São Paulo, were collected from November 1990 to January 1991. Seroprevalence was stratified by age (0-40 years). Mathematical techniques were applied to determine the age-dependent decay function of maternal antibodies during the first year of life, the age-dependent seroprevalence function and the force of infection for CMV in this community., Results: It was observed a descending phase of seropositivity in the first 9 months, but changes in antibody titration were observed between 8 months old and one year of age. The average age of the first infection was 5.02 months of age and 19.84 years, when the age-dependent seroprevalence and the force of infection were analyzed between 10 months of age and 10 years of age and from 10 to 40 years old, respectively., Conclusion: CMV infection is highly prevalent among the population studied and infection occurs in the first year of life. This study shows that most women at reproductive age are vulnerable to the first infection, increasing the risk for congenital infection.
- Published
- 2001
- Full Text
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38. Correlation between HIV and HCV in Brazilian prisoners: evidence for parenteral transmission inside prison.
- Author
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Burattini M, Massad E, Rozman M, Azevedo R, and Carvalho H
- Subjects
- Adult, Brazil epidemiology, Cross-Sectional Studies, HIV Infections blood, HIV Infections transmission, Hepatitis C blood, Hepatitis C transmission, Humans, Male, Multivariate Analysis, Prevalence, Risk-Taking, Seroepidemiologic Studies, Substance Abuse, Intravenous complications, Substance Abuse, Intravenous epidemiology, Syphilis blood, Syphilis epidemiology, Syphilis transmission, HIV Infections epidemiology, Hepatitis C epidemiology, Prisoners statistics & numerical data
- Abstract
Objective: It is an accepted fact that confinement conditions increase the risk of some infections related to sexual and/or injecting drugs practices. Mathematical techniques were applied to estimate time-dependent incidence densities of HIV infection among inmates., Methods: A total of 631 prisoners from a Brazilian prison with 4,900 inmates at that time were interviewed and their blood drawn. Risky behavior for HIV infection was analyzed, and serological tests for HIV, hepatitis C and syphilis were performed, intended as surrogates for parenteral and sexual HIV transmission, respectively. Mathematical techniques were used to estimate the incidence density ratio, as related to the time of imprisonment., Results: Prevalence were: HIV - 16%; HCV - 34%; and syphilis - 18%. The main risk behaviors related to HIV infection were HCV prevalence (OR=10.49) and the acknowledged use of injecting drugs (OR=3.36). Incidence density ratio derivation showed that the risk of acquiring HIV infection increases with the time of imprisonment, peaking around three years after incarceration., Conclusions: The correlation between HIV and HCV seroprevalence and the results of the mathematical analysis suggest that HIV transmission in this population is predominantly due to parenteral exposure by injecting drug, and that it increases with time of imprisonment.
- Published
- 2000
- Full Text
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39. [Mandibular fractures: analysis of 166 cases].
- Author
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Andrade Filho EF, Fadul Junior R, Azevedo RA, Rocha MA, Santos Rd, Toledo SR, Cappucci A, Toledo Junior CS, and Ferreira LM
- Subjects
- Adolescent, Adult, Age Distribution, Brazil epidemiology, Child, Child, Preschool, Female, Humans, Infant, Male, Mandibular Fractures etiology, Mandibular Fractures therapy, Middle Aged, Postoperative Complications epidemiology, Sex Distribution, Mandibular Fractures epidemiology
- Published
- 2000
- Full Text
- View/download PDF
40. Three year seroepidemiological study of varicella-zoster virus in São Paulo, Brazil.
- Author
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Yu AL, Costa JM, Amaku M, Pannuti CS, Souza VA, Zanetta DM, Burattini MN, Massad E, and Azevedo RS
- Subjects
- Adolescent, Age Distribution, Antibodies, Viral blood, Brazil epidemiology, Chickenpox epidemiology, Chickenpox immunology, Child, Child, Preschool, Herpesvirus 3, Human isolation & purification, Humans, Infant, Seroepidemiologic Studies, Antibodies, Viral isolation & purification, Chickenpox blood, Herpesvirus 3, Human immunology
- Abstract
A serosurvey of varicella has been carried out in children attending the public school network of São Paulo city, Brazil, from 1992 to 1994. This study was performed in order to establish the age related prevalence of antibodies against varicella-zoster virus (VZV) and its age specific transmission dynamics pattern in these children. Among 2500 schools in the city of São Paulo public network, 304 were randomly selected; 7 children of a given age (ranging from 1 to 15 years) were randomly selected in each school, and blood samples were obtained by fingerprick into filter paper. Blood eluates were analyzed for the presence of antibodies to VZV by ELISA. Proportion of seropositivity were calculated for each age group. Samples consisted of 1768 individuals in 1992, 1758 in 1993, and 1817 in 1994, resulting in 5343 eluates. A high proportion of seropositive children from 1 to 3 years of age was observed, ascending until 10 years of age and reaching a plateau around 90% afterwards. VZV transmission in this community was similar along the three years of the study. In children attending public schools in the city of São Paulo, contact with VZV occurs in early childhood. If immunization against VZV is considered it should be introduced as soon as possible.
- Published
- 2000
- Full Text
- View/download PDF
41. Serodiagnosis of hepatitis C virus. Effect of new evaluation of cutoff values for enzyme-linked immunosorbent assay in Brazilian patients.
- Author
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dos Santos VA, Azevedo RS, Camargo ME, and Alves VA
- Subjects
- Brazil, Enzyme-Linked Immunosorbent Assay, Evaluation Studies as Topic, Humans, Immunoblotting, Predictive Value of Tests, Sensitivity and Specificity, Hepacivirus isolation & purification, Hepatitis C diagnosis, Serologic Tests methods
- Abstract
With the goal of reducing false-positive results in enzyme-linked immunosorbent assay (ELISA) serodiagnosis of hepatitis C virus in clinical practice, a study was undertaken to establish better cutoff values. We examined 277 serum samples from patients with hepatitis (non-A, non-B; B; autoimmune); subjects with antinuclear antibodies or rheumatoid factor, anticytomegalovirus or Epstein-Barr virus IgG or IgM antibodies, or parasitic disease (Chagas disease, leishmaniasis); and healthy volunteers. Concordant positive results in 2 different immunoblot assays in 250 samples were taken as indicative of true-positive, and when negative, of absence of infection. Reactivity in 3 ELISA tests were evaluated for the manufacturer recommended cutoff (CO) and for 2CO, 3CO, and 4CO; and corresponding sensitivity and specificity were calculated for single or combined pairs of ELISA tests. Although CO is adequate for blood bank screening, because it provides maximal sensitivity, the frequently observed false-positive results could be significantly reduced by increasing the cutoff value to 2CO, with no significant loss in sensitivity either in relation to pairs of immunoenzymatic tests or to a single ELISA.
- Published
- 1999
- Full Text
- View/download PDF
42. Detection of antibodies against hepatitis A virus in eluates of blood spotted on filter-paper: a pilot study in Rio de Janeiro, Brazil.
- Author
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de Almeida LM, Azevedo RS, Guimarães AA, Coutinho Eda S, Struchiner CJ, and Massad E
- Subjects
- Adolescent, Age Distribution, Biomarkers blood, Brazil epidemiology, Child, Child, Preschool, Cross-Sectional Studies, Enzyme-Linked Immunosorbent Assay, Hepatitis A epidemiology, Hepatitis A immunology, Hepatitis A Antibodies, Humans, Infant, Pilot Projects, Predictive Value of Tests, Prevalence, Sensitivity and Specificity, Hepatitis A diagnosis, Hepatitis Antibodies blood
- Abstract
The validity of blood spotted on to filter-paper (BSOFP) eluates for the detection of antibodies against hepatitis A virus (HAV) was investigated in 718 individuals (children and adults) during a field study in a small area in Rio de Janeiro State, Brazil. Serum samples were considered the 'gold standard'. BSOFP eluates were analyzed by 2 different techniques: microplate competitive enzyme-linked immunosorbent assay (ELISA) of the whole study group and microparticle enzyme immune assay (MEIA) of a subsample of 59 individuals. For BSOFP eluates by ELISA, sensitivity and specificity were 89.6% (95% CI: 84.7-93.1) and 97.5% (95% CI: 95.6-98.7), respectively. For a seroprevalence of anti-HAV antibodies of 32%, the positive predictive value was 94.5% (95% CI: 90.3-97.0) and the negative predictive value was 95.2% (95% CI: 92.8-96.8). The test efficiency was 95.0% (95% CI: 93.1-96.4). Similar results were found for BSOFP eluates by MEIA. Agreement between the 2 techniques used for BSOFP (ELISA and MEIA) was also high (kappa = 0.93). These results encourage the more widespread application of BSOFP as a means of surveillance for large-scale epidemiological studies for hepatitis A.
- Published
- 1999
- Full Text
- View/download PDF
43. Seroprevalence of HIV, HCV and syphilis in Brazilian prisoners: preponderance of parenteral transmission.
- Author
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Massad E, Rozman M, Azevedo RS, Silveira AS, Takey K, Yamamoto YI, Strazza L, Ferreira MM, Burattini MN, and Burattini MN
- Subjects
- Adolescent, Adult, Aged, Blood Transfusion, Brazil epidemiology, Enzyme-Linked Immunosorbent Assay, HIV Infections diagnosis, HIV Infections transmission, Hepatitis C diagnosis, Hepatitis C transmission, Humans, Logistic Models, Male, Middle Aged, Multivariate Analysis, Risk-Taking, Seroepidemiologic Studies, Substance Abuse, Intravenous, Syphilis diagnosis, Syphilis transmission, HIV Infections epidemiology, Hepatitis C epidemiology, Prisoners statistics & numerical data, Syphilis epidemiology
- Abstract
Between November 1993 and April 1994, our physicians' team interviewed and took blood samples of 631 prisoners randomly drawn from the largest prison of South America, which counted about 4700 inmates at that time. The interview consisted of questions related to risk behaviour for HIV infection, and the subjects were asked to provide blood for serological tests for HIV, hepatitis C and syphilis. Our main purpose was to investigate the relationship between HCV and injecting drug use as related to HIV seropositivity. Participation in the study was voluntary and confidentiality was guaranteed. Overall prevalences found were as follows: HIV: 16% (95% confidence interval (CI): 13-19%); HCV: 34% (95% CI: 30-38%), and syphilis: 18% (95% CI: 15-21%). Acknowledged use of ever injecting drug was 22% and no other parenteral risk was reported. Our results, as compared with other studies in the same prison, suggest that HIV prevalence has been stable in recent years, and that the major risk factor for HIV infection in this population is parenteral exposure by injecting drug use.
- Published
- 1999
- Full Text
- View/download PDF
44. Infection with group C rotavirus in a suburban community in Brazil.
- Author
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Cox MJ, James VL, Azevedo RS, Massad E, and Medley GF
- Subjects
- Adolescent, Adult, Aged, Antibodies, Viral blood, Brazil epidemiology, Child, Child, Preschool, Humans, Infant, Infant, Newborn, Middle Aged, Rotavirus Infections transmission, Seroepidemiologic Studies, Rotavirus Infections epidemiology
- Abstract
Group C rotaviruses are associated with sporadic outbreaks of gastroenteritis worldwide. Age-specific seroprevalence of group C rotavirus antibodies was investigated in sera, randomly collected and representative of a suburban community in Brazil which had previously been screened for group A rotavirus antibodies. Antibody prevalence to group C rotavirus was low in children under 5 years and increased slowly with age to 36% seropositivity in adults, reflecting continuous exposure to primary infection in all age groups. This suggests a higher incidence of infection than disease might predict. Adult antibody prevalence was similar to that in other geographical settings. No obvious patterns of infection with group A and group C rotavirus were found within individuals, which suggests independent transmission. However, further epidemiological studies are required to understand group C rotavirus dynamics and possible interactions with group A rotavirus transmission and immunity.
- Published
- 1998
- Full Text
- View/download PDF
45. Seroepidemiological study of respiratory syncytial virus in São Paulo state, Brazil.
- Author
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Cox MJ, Azevedo RS, Cane PA, Massad E, and Medley GF
- Subjects
- Adolescent, Adult, Age Factors, Brazil epidemiology, Child, Child, Preschool, Enzyme-Linked Immunosorbent Assay, Female, Humans, Immunoglobulin G blood, Infant, Infant, Newborn, Male, Pregnancy, Respiratory Syncytial Virus Infections immunology, Rubella Vaccine administration & dosage, Seasons, Seroepidemiologic Studies, Antibodies, Viral blood, Respiratory Syncytial Virus Infections epidemiology, Respiratory Syncytial Viruses immunology
- Abstract
Transmission of respiratory syncytial virus is thought to be highly seasonal based on reported clinical cases, although transmission resulting in mild disease in all age groups has been little studied. This has been investigated in a seroepidemiological survey using sera from São Paulo, Brazil. Seroprevalence was found to increase rapidly with age, reaching over 90% by three years of age. This is typical of viral infections, which produce life-long immunity following primary infection. One-hundred percent seropositivity was attained by five years of age and maintained throughout adulthood, whereas mean antibody titers continued to increase with age. The mean duration of maternal antibodies was estimated to be 3.3 months with antibody decay demonstrated in paired samples from infants. The results are discussed in relation to possible mechanisms generating such a profile.
- Published
- 1998
- Full Text
- View/download PDF
46. Seroepidemiology of group A rotavirus in suburban São Paulo, Brazil.
- Author
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Cox MJ, Azevedo RS, Nokes DJ, Beards GM, McCrae MA, Massad E, and Medley GF
- Subjects
- Adolescent, Adult, Age Factors, Brazil epidemiology, Child, Child, Preschool, Humans, Immunization, Immunoglobulin A blood, Immunoglobulin G blood, Immunoglobulin M blood, Infant, Infant, Newborn, Rotavirus Infections prevention & control, Antibodies, Viral blood, Rotavirus Infections epidemiology
- Abstract
Age-specific patterns of rotavirus infection were investigated using a randomly selected and representative sample of sera from a suburban community of São Paulo, Brazil screened for class-specific antibodies to group A rotavirus. Age-serology of anti-rotavirus IgG showed primary infection predominant in young infants with a median age of around 18 months consistent with IgM serology suggesting highest rates of recent infection between ages 4 and 48 months. Anti-rotavirus serum IgA prevalence increased gradually with age. Paired samples from infants, collected 1 month apart, indicated high exposure rates with seroconversion occurring in several infants during the reported low transmission season. Between 5 and 10% of adults had elevated IgM levels indicative of recent infection and, potentially, of an important contribution adults may play to rotavirus transmission. Further understanding of the dynamics of rotavirus transmission within populations, at group and serotype level, would benefit the design and monitoring of future immunization programmes.
- Published
- 1998
- Full Text
- View/download PDF
47. Measles antibody levels in a vaccinated population in Brazil.
- Author
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Cox MJ, Azevedo RS, Massad E, Fooks AR, and Nokes DJ
- Subjects
- Adolescent, Adult, Age Distribution, Brazil epidemiology, Child, Child, Preschool, Humans, Immunity, Active, Immunity, Maternally-Acquired, Immunization, Infant, Infant, Newborn, Measles epidemiology, Measles prevention & control, Urban Health, Antibodies, Viral analysis, Immunoglobulin G analysis, Measles immunology, Measles Vaccine immunology
- Abstract
An epidemiological study of measles-specific immunoglobulin G antibody levels was conducted using a representative sample of a vaccinated suburban population in São Paulo State, Brazil. The study aimed to determine immunity status in relation to age and infection or vaccination experience. 549 age-structured samples of sera, collected in 1990, were screened and calibrated to the international reference serum, using measles nucleoprotein in an enzyme immunoassay. In the age group with direct experience of vaccination (9 months to 15 years), whether routine or campaign, over 90% had detectable antibody > or = 50 miu/mL. However, 14% of these had antibody concentrations between 50 and 100 miu/mL and 30% between 50 and 255 miu/mL. In those over 15 years of age, 94% had antibody levels > 255 miu/mL, assumed to be the result of past infection. The study suggested that, within highly vaccinated populations, a proportion of individuals had measles antibody levels which may be insufficient to protect against reinfection or clinical disease. The implications of these results, and similar findings elsewhere, in relation to the persistence of measles requires investigation; this has particular relevance in São Paulo following the recent measles outbreak.
- Published
- 1998
- Full Text
- View/download PDF
48. Reliability of environmental, biological and health characteristics of infants from a developing country.
- Author
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Fuchs SC, Victora CG, Wannmacher L, Gonçalves C, Barbosa A, Menta L, and Azevedo R
- Subjects
- Adolescent, Adult, Brazil epidemiology, Epidemiologic Methods, Female, Humans, Infant, Maternal Age, Observer Variation, Reproducibility of Results, Risk Factors, Delivery of Health Care statistics & numerical data, Developing Countries statistics & numerical data, Environment, Pneumonia epidemiology
- Abstract
Background: Although most epidemiological data are gathered by interviews, few studies ascertain their reliability. This study quantified inter-observer reliability of environmental, biological and health characteristics of underprivileged children, in a southern Brazilian state., Methods: Five health care professionals who had received extensive standardized interview and observation training interviewed mothers and observed the home environments of a random sample of 102 children. A second interview was conducted by a sixth health professional who had received separate but identical training without the initial interviewer knowing a follow-up interview would be conducted. Data from the two independent interviews and observations were compared for agreement using the kappa statistic., Results: There was excellent agreement (kappa > 0.75) for most of the household characteristics, such as type of walls, ceiling, floor and windows in spite of the diversity of buildings. Presence of the parents, number of people in the house-hold, age of the mother and health assistance were reliable as well. However, information about skin colour of the mother and the number of cracks in the house only reached fair agreement., Conclusions: These results showed that data gathered by observation and interviews generate accurate information about environmental, biological and health care characteristics. Those based on written information, such as birth date, were highly concordant.
- Published
- 1996
- Full Text
- View/download PDF
49. [Prevalence of serologic markers of hepatitis B and D viruses in children of the Caiabi and Txucarramãe tribes from the Indian Reservation of Xingu, central Brazil].
- Author
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Azevedo RA, Silva AE, Ferraz ML, Marcopito LF, and Baruzzi RG
- Subjects
- Adolescent, Age Distribution, Biomarkers blood, Brazil epidemiology, Brazil ethnology, Child, Child, Preschool, Female, Hepatitis B immunology, Hepatitis D immunology, Hepatitis delta Antigens, Humans, Infant, Infant, Newborn, Male, Topography, Medical, Hepatitis Antigens blood, Hepatitis B epidemiology, Hepatitis B Surface Antigens blood, Hepatitis B e Antigens blood, Hepatitis D epidemiology, Indians, South American
- Abstract
The medical literature has shown that the inhabitants of the Amazon region are highly affected by hepatitis B and delta viruses infection, but this has never been studied in Indian children by age group. A study of the prevalence of serological markers of hepatitis B and delta viruses in Indian children aged 0 to 14 years living in the PIX was carried out. This Park is located in Central Brazil, a region which is in the transition between the savannab to the south and the Amazon jungle to the north. To determine the prevalence of HBV and HDV markers in Indian children and to characterize the route of HBV transmission in this region. Out of the 17 tribes living in the PIX, two--the Caiabi and the Txucarramãe--were chosen because both live in the North part of the Park, but have quite different ways of life. The overall prevalence of HBV serum markers was: HBsAg, 4.5%; anti-HBs, 39.6%; anti-HBc, 44.1%; any marker of HBV, 47.3%; and anti-HDV, 0.0%. However, a striking difference in the prevalence of hepatitis B markers was observed between the two tribes: younger Caiabi children were much less affected than the Txucarramãe ones. The prevalence of HBsAg in fertile women was 12%, being anti-HBe positive. Our data suggest that HBV infection is highly prevalent among Indian children living in this Indigenous Park and vertical infection is not an important route of transmission in either tribes.
- Published
- 1996
- Full Text
- View/download PDF
50. Rotavirus serotypes and electrophoretypes among children attending three paediatric hospitals in Belem, Brazil.
- Author
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Linhares AC, Moura JM, Gabbay YB, Mendes PS, Mascarenhas JD, and de Azevedo RC
- Subjects
- Brazil, Child, Preschool, Electrophoresis, Polyacrylamide Gel, Hospitals, Pediatric, Humans, Infant, RNA, Viral analysis, Serotyping, Diarrhea, Infantile microbiology, Rotavirus classification, Rotavirus Infections microbiology
- Abstract
From March to September 1988 stool specimens of 101 hospitalized diarrhoeic infants and children, aged 1-24 months were examined by enzyme-linked immunosorbent assay (ELISA) for the presence of rotavirus antigen. This agent was found in 40 (40 per cent) of the 101 episodes of acute diarrhoea, and strains were both characterized by analysis of RNA in polyacrilamide gel and serotyped by ELISA using serotype-specific monoclonal antibodies. The highest frequency of rotavirus positivity was 80 per cent in the 16-18 month age group. All 11 (28 per cent) serotyped strains belonged to serotype 3 whereas absence of Vp7, the major outer capsid glycoprotein, did not allow serotyping in 29 (73 per cent) of the 40 rotavirus-positive specimens. Four distinct electrophoretypes were detected and the predominant one had the IbIIbIIIgIV a profile, accounting for 62 per cent of the classified strains. Unclear patterns did not allow us to determine the electrophoretype of six rotavirus strains. The clinical picture in study children was in general of moderate/severe nature.
- Published
- 1993
- Full Text
- View/download PDF
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