Description of Rhodnius montenegrensis n. sp (Hemiptera: Reduviidae: Triatominae) from the state of Rondonia, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Isolation and identification of mycobacteria from livestock specimens and milk obtained in Brazil

The prevalence of Mycobacterium bovis and other mycobacterial species in livestock specimens and milk was evaluated. An emphasis was placed upon the distribution of these organisms in milk that is readily available to the public that was either untreated, pasteurized, or treated using ultra high temperature. Twenty-two pathologic specimens from livestock (bovine, swine and bubaline) in five Brazilian states and 128 bovine milk samples from retail markets in the State of São Paulo were examined for mycobacteria. Identification was made by classical biochemical tests, thin layer chromatography of mycolic acids and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Mycobacteria were isolated from 15 (68.2%) caseous lesions and from 23 (18%) milk samples. Eleven isolates were identified as M. bovis, and the remaining 27 nontuberculous mycobacterial isolates were represented by five species and six unidentified rapidly growing mycobacterial strains. The data demonstrate that animal products in Brazil are frequent reservoirs of mycobacteria and may pose a risk to the public.

Genes do eixo somatotrófico e características de crescimento numa população F2 de bovinos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Polimorfismos genéticos da kappa-caseína e da beta-lactoglobulina e produção de leite em bovinos

As variantes gênicas da beta-lactoglobulina (β-LG) e da kappa-caseína (κ-CN) bovinas são associadas à produção, qualidade e características de processamento do leite. O objetivo deste trabalho foi analisar as frequências dos genótipos AA, AB e BB, por meio da técnica de PCR-RFLP, da β-LG e da κ-CN bovinas, e suas associações com a produção de leite (kg leite/dia) em bovinos das raças Girolanda, Holandesa e Jersey. Para a κ-CN, a frequência do genótipo AA foi maior nos animais das raças Holandesa (37%) e Girolanda (63%). Na raça Jersey, houve predomínio do genótipo BB (60%). Para a β-LG, o genótipo AB foi o mais encontrado nas raças Girolanda (54%) e Holandesa (58%), enquanto nos animais da raça Jersey houve predomínio do genótipo BB (45%). Houve associação do alelo B da κ-CN com maior produtividade leiteira nas raças Girolanda e Holandesa, e do alelo A da β-LG com maior produtividade de leite na raça Jersey. As variantes genéticas da κ-CN podem ser usadas como marcadores na seleção para a produtividade leiteira nas raças Girolanda e Holandesa. Para a raça Jersey, as variantes da β-LG seriam mais adequadas para essa seleção.

Duffy blood group gene polymorphisms among malaria vivax patients in four areas of the Brazilian Amazon region

Background: Duffy blood group polymorphisms are important in areas where Plasmodium vivax predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in P. vivax malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria.Methods: the P. vivax identification was determined by non-genotypic and genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP in 330 blood donors and 312 malaria patients from four Brazilian Amazon areas. In order to assess the variables significance and to obtain independence among the proportions, the Fisher's exact test was used.Results: the data show a high frequency of the FYA/FYB genotype, followed by FYB/FYB, FYA/FYA, FYA/FYB-33 and FYB/FYB-33. Low frequencies were detected for the FYA/FY(X), FYB/FY(X), FYX/FY(X) and FYB-33/FYB-33 genotypes. Negative Duffy genotype (FYB-33/FYB-33) was found in both groups: individuals infected and non-infected (blood donors). No individual carried the FY(X)/FYB-33 genotype. Some of the Duffy genotypes frequencies showed significant differences between donors and malaria patients.Conclusion: the obtained data suggest that individuals with the FYA/FYB genotype have higher susceptibility to malaria. The presence of the FYB-33 allele may be a selective advantage in the population, reducing the rate of infection by P. vivax in this region. Additional efforts may contribute to better elucidate the physiopathologic differences in this parasite/host relationship in regions endemic for P. vivax malaria, in particular the Brazilian Amazon region.

Polymorphism of the ITS-2 region of the ribosomal DNA of the Triatominae Rhodnius domesticus, R-pictipes, R-prolixus and R-stali

The polymerase chain reaction-restriction fragment length polymorphism technique (PCR-RFLP) was used to compare Rhodnius domesticus (Neiva & Pinto), R. pictipes (Stal), R. prolixus (Stal) and R. stali (Lent; Jurberg & Galvao) (Hemiptera: Reduviidae). The enzyme BstUI differentiated R. donzesticus, R. pictipes and R. prolixus, and HhaI differentiated R. domesticus, R. pictipes and R. stali. With the fingerprinting analysis generated by these two enzymes, it was possible to clearly identify all four species in the study.

Detection and differentiation of Leptospira spp. serovars in bovine semen by polymerase chain reaction and restriction fragment length polymorphism

In view of the importance of venereal transmission of bovine leptospirosis, the objective of the present study was to apply the polymerase chain reaction (PCR) to 26 serovars of Leptospira interrogans, L. borgpetersenii, L. santarosai, L. noguchii and L. biflexa, to determine the detection threshold in semen samples and to evaluate the possibility of differentiation among serovars using 19 restriction endonucleases. The results showed that all serovars were amplified and the detection threshold in semen samples of a bull was 100 bacteria/ml. Using endonucleases we could classify the 26 serovars into eight groups. The present results show that PCR is a method of great potential for the detection of Leptospira spp, at bovine artificial insemination centers. (C) 2000 Elsevier B.V. B.V. All rights reserved.

Loss of imprinting and loss of heterozygosity on 11p15.5 in head and neck squamous cell carcinomas

Background. IGF2 and H19 are reciprocal imprinted genes with paternal and maternal monoallelic expression, respectively. This is interesting, because IGF2 is known as a growth factor, and H19 encodes a RNA with putative tumor suppressor action. Furthermore, IGF2 and H19 are linked genes located on chromosome 11p15.5, a common site of loss of heterozygosity in human cancers.Methods. We performed an allelic-typing assay using a PCR-RFLP-based method for identification of heterozygous Informative cases in head and neck squamous cell carcinomas. Tumoral total RNA was extracted from each of the heterozygotes and further studied by RT-PCR analysis.Results. We detected the expression of the IGF2 gene in 10 of 10 informative cases. Two cases exhibited LOI of the IGF2 gene as evidenced by biallelic expression, and in another case, LOH was coupled with monoallelic expression of this growth factor. LOI for the H19 gene was observed in 1 of 14 informative samples analyzed. In this case, we also detected parallel mono-allelic expression of the IGF2 gene. Down-regulation of the H19 gene was observed in 10 of 14 cases.Conclusion. These findings support the hypothesis that H19 may be a tumor suppressor gene involved In head and neck carcinogenesis. Furthermore, our data showed that genetic and epigenetic chances at 11p15.5 could lead to abnormal expression of imprinted genes in HNSCC. (C) 2001 John Wiley & Sons, Inc.

Hemoglobin and HFE gene polymorphisms in Brazilian populations in regions endemic for malaria

Our objective was to determine how the distribution of red blood cell diseases is related to malaria occurrence in north Brazil, a region endemic for malaria. We evaluated the incidence of two mutations in the HFE gene, H63D and C282Y, in two study groups: a control blood donor group, with no indication of malaria infection, and a group constituted of malaria patients of four states of the Amazonian region. The hemoglobin polymorphisms were obtained by HPLC and classical laboratory methodologies, and the two mutations in the HFE gene were assayed by PCR-RFLP. We found a high frequency of alpha thalassemia, but there were no significant differences between blood donors and malaria patients. There were also no significant differences in the frequencies of HbA(2); however, the frequency of HbF was significantly different in individuals with malaria from Para and Rondonia. The mean number of reticulocytes was significantly reduced in the blood donors from the northern region, suggesting an adaptive strategy of these populations to parasitic attack by Plasmodium. Most individuals were heterozygous for the H63D allele of the HFE gene in both study groups. In the blood donors group, the greatest frequency of the H63D allele was found in Caucasians of all the states. In the malaria patients group in Rondonia, there was a high frequency of the H63D allele among the non-Caucasians. In the other states, and in the malaria patients group, the H63D allele was the most frequent among the Caucasians. Based on our results, we suggest that the maintenance of polymorphism of the mutations in the gene HFE can be explained by selective factors other than malaria, or it is due to simple allelic oscillation and by the constant gene flow among the populations in Brazil.

Polymorphisms of DNA repair genes XRCC1 and XRCC3, interaction with environmental exposure and risk of chronic gastritis and gastric cancer

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Plasmodium vivax infection among Duffy antigen-negative individuals from the Brazilian Amazon region: an exception?

We present evidence for Plasmodium vivax infection among Duffy blood group-negative inhabitants of Brazil. The P. vivax identification was determined by both genotypic and non-genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP and phenotyped using a microtyping kit. We detected two homozygous FY*B-33 carriers infected by P vivax, whose circumsporozoite protein genotypes were VK210 and/or P. vivax-like. Additional efforts are necessary in order to clarify the evidence that P. vivax is being transmitted among Duffy blood group-negative patients from the Brazilian Amazon region. (C) 2007 Published by Elsevier Ltd on behalf of Royal Society of Tropical Medicine and Hygiene.

A new polymerase chain reaction/restriction fragment length polymorphism protocol for Plasmodium vivax circumsporozoite protein genotype (VK210, VK247, and P-vivax-like) determination

For the molecular diagnosis of Plasmodium vivax variants (VK210, VK247, and P. vivax-like) using DNA amplification procedures in the laboratory, the choice of rapid and inexpensive identification products of the 3 different genotypes is an important prerequisite. We report here the standardization of a new polymerase chain reaction/restriction fragment length polymorphism technique to identify the 3 described P. vivax circumsporozoite protein (CSP) variants using amplification of the central immunodominant region of the CSP gene of this protozoan. The simplicity, specificity, and sensitivity of the system described here is important to determine the prevalence and the distribution of infection with these P. vivax genotypes in endemic and nonendemic malaria areas, enabling a better understanding of their phylogeny. (c) 2007 Published by Elsevier B.V.

MOLECULAR DIAGNOSIS of LEISHMANIA AMAZONENSIS IN A CAPTIVE SPIDER MONKEY IN BAURU, São Paulo, BRAZIL

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

VIABILITY of SPORULATED OOCYSTS of NEOSPORA CANINUM AFTER EXPOSURE TO DIFFERENT PHYSICAL and CHEMICAL TREATMENTS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The 844ins68 cystathionine beta-synthase and C677T MTHFR gene polymorphism and the vaso-occlusive event risk in sickle cell disease

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)