116 resultados para Molecular analysis


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INTRODUCTION: This work was an epidemiological investigation of the risk of Trypanosoma cruzi transmission in the rural Quilombola community of Furnas do Dionízio, State of Mato Grosso do Sul, Brazil. METHODS: Of the 71 animals examined, seven were captured (two opossums, Didelphis albiventris; four rats, Rattus rattus; and one nine-banded armadillo, Dasypus novemcinctus) and 64 were domestic (one canine, Canis familiaris; five pigs, Sus scrofa; two bovines, Bos taurus; five caprines, Capra sp.; and 51 ovines, Ovis aries). Parasitological tests were performed to detect parasites in the blood and to identify the morphology of flagellates. These methods included fresh examinations, buffy coat tests and blood cultures. Molecular analysis of DNA for identification of trypanosomatids was performed by polymerase chain reaction (PCR) with primers S35 and S36. RESULTS: The parasitological tests showed flagellates in an opossum and two cattle. The molecular tests showed DNA from T. cruzi in an opossum and a pig. Triatoma sordida was the only triatomine species found in the community, and it colonized households (four specimens) and the surrounding areas (124 specimens). Twenty-three specimens tested positive for flagellates, which were subsequently identified as T. cruzi by PCR. CONCLUSIONS: Data analysis demonstrated that T. cruzi has a peridomestic life cycle that involves both domestic and wild mammals.

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Introduction In this study, the clinical features, underlying diseases and clinical outcomes of patients with cryptococcosis were investigated. In addition, a molecular analysis of the Cryptococcus neoformans species complex isolated from these patients was performed. Methods A prospective study of 62 cases of patients with cryptococcal infection was conducted at the Hospital de Doenças Tropicais de Goiás Dr. Anuar Auad from 2009-2010. Cryptococcal meningitis cases were diagnosed by direct examination and cerebrospinal fluid (CSF) sample culture. The profiling of these patients was assessed. The CSF samples were submitted to India ink preparation and cultured on Sabouraud dextrose agar, and C. neoformans was identified by the production of urease, a positive phenoloxidase test and assimilation of carbohydrates. C. neoformans and C. gattii isolates were distinguished by growth on L-canavanine-glycine-bromothymol blue medium, and molecular analysis was conducted via PCR fingerprinting reactions using M13 and (GACA)4 primers. Results From the 62 patients with cryptococcosis, 71 isolates of CSF were obtained; 67 (94.4%) isolates were identified as C. neoformans var. grubii/VNI, and 4 (5.6%) were identified as C. gattii/VGII. Of these patients, 53 had an HIV diagnosis. The incidence of cryptococcosis was higher among patients 20-40 years of age, with 74.2% of the cases reported in males. Cryptococcus-related mortality was noted in 48.4% of the patients, and the symptoms were altered sensorium, headache, fever and stiff neck. Conclusions The high morbidity and mortality observed among patients with cryptococcosis demonstrate the importance of obtaining information regarding the epidemiological profile and clinical course of the disease in the State of Goiás, Brazil.

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This article takes an ecological approach to the genetic diversity of Rosewood (Aniba rosaeodora Ducke) in a central Amazonian terra firme forest north of Manaus. Planted Rosewood setting, under partial shaded canopy, were assessed in terms of fruiting production, frugivory, and seed dispersal. Using RAPD molecular analysis procedures, the influence of the spatial distribution of adult trees on the genetic diversity (polymorphism) of saplings was assessed with genetic samples from 34 reproductive trees and 60 saplings. The density and distribution patterns the reproductive trees did not modify the sapling"s diversity (1.86%, AMOVA). Two types of adult tree dispersion were identified; i) clumped and ii) more widely dispersed. Polymorphism (77.5%) and gene flow were high between these. Although more sapling genetic variability in areas with a higher density of mature plants was not as high as expected, density did not affect the genetic diversity of samplings, indicating a high incidence of gene flow amongst trees. In planted Rosewood population (surrounded by low disturbed forest), fruiting trees experienced a high level of removal of seeds by toucans (Rhamphastidae), about of 50%. The high gene flow found among native trees suggested that toucans, promoting seed rain at short and long distances from maternal trees, actively contribute to the maintenance of genetic diversity within wild rosewood populations.

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OBJECTIVE - Cardiac evaluation (clinical, electrocardiographic and echocardiographic) of 25 Brazilian patients with clinical diagnosis of Friedreich's ataxia (FA) related to the frequency and the size of GAA repeats (unstable expansion of trinucleotide repeats that results in the disease). METHODS - Clinical and cardiac study including electrocardiogram and echocardiogram of all patients and molecular analysis to detect the frequency and the size of GAA expansion, by polymerase chain reaction analysis. RESULTS - Homozygous GAA expansion was detected in 17 patients (68%) -- all typical cases. In 8 (32%) cases (6 atypical and 2 typical), no GAA expansion was observed, therefore it was not considered Friedreich's ataxia. All patients with GAA expansion (100%) had electrocardiographic abnormalities, and only 25% of the cases without GAA expansion had some abnormality on this exam. However, only 6% of all patients revealed some signals/symptoms suggestive of cardiac involvement. CONCLUSION - A molecular analysis is essential to confirm the diagnosis of Friedreich's ataxia; however, an adequate cardiac evaluation, including an electrocardiogram, was extremely useful to better screening the patients which should perform these molecular analysis.

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Unequal sex ratios lead to the loss of genetic variability, decreasing the viability of populations in the long term. Anthropogenic activities often disturb the natural habitats and can cause alterations in sex ratio and morphological characteristics of several species. Forest fragmentation is a major conservation concern, so that understanding its effects in natural populations is essential. In this study, we evaluated the sex ratio and the morphological characteristics of Rufous Gnateaters (Conopophaga lineata (Wied, 1831)) in small and large forest fragments in Minas Gerais, Brazil. Birds (n = 89) were sexed by plumage characteristics and molecular markers. The molecular analysis showed that plumage is not a totally reliable method for sexing Rufous Gnateaters. We observed that sex ratio did not differ between large and small forest fragments, but birds in small fragments had larger wings and tarsus. Wing and tarsus changes may affect the movement ability of individuals within and among forest fragments. In conclusion, Rufous Gnateaters have been able to survive in both small and large Atlantic rain forest fragments without altering their sex ratio, but morphological changes can be prejudicial to their long term survival.

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We identified a gametocyte-specific protein of Plasmodium falciparum called Pf11-1 and provide experimental evidence that this molecule is involved in the emergence of gametes of the infected erythrocyte (gametogenesis). A mutant parasite clone, which has deleted over 90% of the PF11-1 gene locus, was an important control to establish the gametocyte-specific expression of the Pf11-1. Molecular analysis of the Pf11-1 deletion indicates that it is presumably due a chromosome breakage with subsequent "healing" by the addition of telomeric heptanucleotides. Moreover, similar DNA rearrangements are observed in most of the laboratory isolates during asexual propagation in vitro.

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In Cuba, several Biomphalaria species have been reported such as B. orbignyi, B. schrammi, B. helophila, B. havanensis and B. peregrina; only the latter three are considered as potential hosts of Schistosoma mansoni. The specific identification of Biomphalaria species is based on anatomical and morphological characters of genital organs and shells. The correct identification of these snails is complicated by the high variation in these characters, similarity among species and in some cases by the small size of the snails. In this paper, we reported the classical morphological identification, the use of PCR and RFLP analysis of the internal transcribed spacer region of the ribosomal RNA genes for molecular identification of seven snail populations from different localities in Cuba. Using morphological and molecular analysis, we showed that among the studied Cuban Biomphalaria populations only B. havanensis and B. obstructa species were found.

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Molecular evidence showed 46.2% of Trypanosoma cruzi infection in Mepraia spinolai insects from North-Central Chile, which is significantly higher than previous reports of up to 26% by microscopic observation. Our results show similar infection levels among nymphal stages, ranging from 38.3 to 54.1%, indicating that younger nymphs could be as important as older ones in parasite transmission. A cautionary note must be stressed to indicate the potential role of M. spinolai in transmitting T. cruzi in country areas due to the high infection level detected by molecular analysis.

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This study focuses on the geographic distribution of the snail of the genus Biomphalaria and evaluates its infectivity by Schistosoma mansoni in 5264 specimens collected in the municipality of Juiz de Fora, Minas Gerais, Brazil. Of the 31 locations studied, 6 were reservoirs, 11 rudimentary holding ponds, 7 irrigation ditches, 5 lakes, 1 ornamental pond, and 1 waterfall. Intermediate hosts were found only in the rudimentary ponds and ditches, which were 100% positive. Using morphological and molecular analysis techniques, B. tenagophila, B. peregrina, and B. straminea were identified. This is the first report of B. stramínea in the municipality, and evaluation of its infective potential revealed susceptibility of 25.4%. Although we did not find specimens of Biomphalaria infected by S. mansoni, the data obtained indicate the presence of intermediate hosts, especially in the irrigation ditches in Juiz de Fora, and their proximity to contaminated areas.

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This paper presents the morphological, histological and ultrastructural characteristics of Myxobolus oliveirai sp. nov., a parasite of the gill filaments in Brycon hilarii from the Brazilian Pantanal. Out of 216 B. hilariispecimens examined (126 wild and 90 cultivated), 38.1% of wild specimens (n = 48) were infected. The parasites form elongated plasmodia primarily in the tip of gill filaments, reaching about 3 mm in length. A thorough comparison with all the Myxobolus species described from South American hosts, as well as nearly all the Myxobolus species described so far is provided. Partial sequencing of the 18S rDNA gene revealed a total of 1,527 bp. The Myxobolus species parasite of B. hilarii did not match any of the Myxozoa available in GenBank. In the phylogenetic analysis, M. oliveirai sp. nov. composed a monophyletic group with eight other species: five species of Myxobolus parasites of mugilid fishes, two parasites of pangasiid and one of centrarchid. Infection prevalence values of the parasite revealed no significant differences between wet and dry seasons or between males and females. The importance of the infection to the farming of the host species is emphasized.

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Malaria is still a primary health problem in Colombia. The locality of Tierradentro is situated in the municipality of Montelíbano, Córdoba, in the northwest of Colombia, and has one of the highest annual parasite index of malaria nationwide. However, the vectors involved in malaria transmission in this locality have not yet been identified. In this study, the local anthropophilic Anopheles composition and natural infectivity with Plasmodium were investigated. In August 2009, 927 female Anopheles mosquitoes were collected in eight localities using the human landing catch method and identified based on their morphology. Cryptic species were determined by restriction fragment length polymorphism-internal transcribed spacer (ITS)2 molecular analysis. Eight species [Anopheles nuneztovari s.l. (92.8%), Anopheles darlingi (5.1%), Anopheles triannulatus s.l. (1.8%), Anopheles pseudopunctipennis s.l. (0.2%), Anopheles punctimacula s.l. (0.2%), Anopheles apicimacula (0.1%), Anopheles albimanus (0.1%) and Anopheles rangeli (0.1%)] were identified and species identity was confirmed by ITS2 sequencing. This is the first report of An. albimanus, An. rangeli and An. apicimacula in Tierradentro. Natural infectivity with Plasmodium was determined by ELISA. None of the mosquitoes was infectious for Plasmodium. An. nuneztovari s.l. was the predominant species and is considered the primary malaria vector; An. darlingi and An. triannulatus s.l. could serve as secondary vectors.

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Studies on natural infection by Leishmania spp of sandflies collected in endemic and nonendemic areas can provide important information on the distribution and intensity of the transmission of these parasites. This study sought to investigate the natural infection by Leishmaniain wild female sandflies. The specimens were caught in the city of Corumbá, state of Mato Grosso do Sul (Brazil) between October 2012-March 2014, and dissected to investigate flagellates and/or submitted to molecular analysis to detect Leishmania DNA. A total of 1,164 females (77.56% of which were Lutzomyia cruzi) representing 11 species were investigated using molecular analysis; 126 specimens of Lu. cruziwere dissected and also submitted to molecular analysis. The infection rate based on the presence of Leishmania DNA considering all the sandfly species analysed was 0.69%; only Leishmania (Leishmania) amazonensis was identified in Lu. cruzi by the molecular analysis. The dissections were negative for flagellates. This is the first record of the presence of L. (L.) amazonensis DNA in Lu. cruzi, and the first record of this parasite in this area. These findings point to the need for further investigation into the possible role of this sandfly as vector of this parasite.

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The influence of different infectious agents and their association with human papillomavirus (HPV) in cervical carcinogenesis have not been completely elucidated. This study describes the association between cytological changes in cervical epithelium and the detection of the most relevant aetiological agents of sexually transmitted diseases. Samples collected from 169 patients were evaluated by conventional cytology followed by molecular analysis to detect HPV DNA, Chlamydia trachomatis, herpes simplex virus 1 and 2,Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, andTreponema pallidum, besides genotyping for most common high-risk HPV. An association between cytological lesions and different behavioural habits such as smoking and sedentariness was observed. Intraepithelial lesions were also associated with HPV and C. trachomatis detection. An association was also found between both simple and multiple genotype infection and cytological changes. The investigation of HPV and C. trachomatisproved its importance and may be considered in the future for including in screening programs, since these factors are linked to the early diagnosis of patients with precursor lesions of cervical cancer.

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This work had as objective to produce citrus somatic hybrids between sweet oranges and pummelos. After chemical fusion of sweet orange embryogenic protoplasts with pummelo mesophyll-derived protoplasts, plants were regenerated by somatic embryogenesis and acclimatized in a greenhouse. The hybrids of 'Hamlin' sweet orange + 'Indian Red' pummelo and 'Hamlin' sweet orange + 'Singapura' pummelo were confirmed by leaf morphology, chromosome counting and molecular analysis. These hybrids have potential to be used directly as rootstocks aiming blight, citrus tristeza virus, and Phytophthora-induced disease tolerance, as well as for rootstocks improvement programs.

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The fungus Stemphylium solani causes leaf blight of tomato (Lycopersicon esculentum) in Brazil. In recent years, severe epidemics of a new leaf blight of cotton (Gossipium hyrsutum) caused by S. solani occurred in three major cotton-growing Brazilian states (PR, MT and GO). Molecular analysis was performed to assess the genetic diversity among the S. solani isolates from cotton, and to verify their relationship with representative S. solani isolates from tomato. Random amplified polymorphic DNA (RAPD) markers and internal transcribed spacers of ribosomal DNA (rDNA) were used to compare 33 monosporic isolates of S. solani (28 from cotton and five from tomato). An isolate of Alternaria macrospora from cotton was also used for comparison. RAPD analysis showed the presence of polymorphism between the genera and the species. The A. macrospora and the S. solani isolates from cotton and tomato were distinct from each other, and fell into separate groups. Variation by geographic region was observed for the tomato isolates but not for the cotton isolates. Amplifications of the ITS region using the primer pair ITS4/ITS5 resulted in a single PCR product of approximately 600 bp for all the isolates. Similarly, when amplified fragments were digested with eight restriction enzymes, identical banding patterns were observed for all the isolates. Hence, rDNA analysis revealed no inter-generic or intra-specific variation. The genetic difference observed between the cotton and the tomato isolates provides evidence that S. solani attacking cotton in Brazil belongs to a distinct genotype.