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1.
Braz. j. microbiol ; 49(2): 429-442, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889226

RESUMO

Abstract Bacteria are important sources of cellulases with various industrial and biotechnological applications. In view of this, a non-hemolytic bacterial strain, tolerant to various environmental pollutants (heavy metals and organic solvents), showing high cellulolytic index (7.89) was isolated from cattle shed soil and identified as Bacillus sp. SV1 (99.27% pairwise similarity with Bacillus korlensis). Extracellular cellulases showed the presence of endoglucanase, total cellulase and β-glucosidase activities. Cellulase production was induced in presence of cellulose (3.3 times CMCase, 2.9 times FPase and 2.1 times β-glucosidase), and enhanced (115.1% CMCase) by low-cost corn steep solids. An in silico investigation of endoglucanase (EC 3.2.1.4) protein sequences of three Bacillus spp. as query, revealed their similarities with members of nine bacterial phyla and to Eukaryota (represented by Arthropoda and Nematoda), and also highlighted of a convergent and divergent evolution from other enzymes of different substrate [(1,3)-linked beta-d-glucans, xylan and chitosan] specificities. Characteristic conserved signature indels were observed among members of Actinobacteria (7 aa insert) and Firmicutes (9 aa insert) that served as a potential tool in support of their relatedness in phylogenetic trees.


Assuntos
Animais , Bovinos , Bacillus/enzimologia , Celulase/genética , Celulase/metabolismo , Evolução Molecular , Bacillus/crescimento & desenvolvimento , Bacillus/isolamento & purificação , Celulose/metabolismo , Biologia Computacional , Fezes/microbiologia , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Mutação INDEL , Análise de Sequência de DNA , Homologia de Sequência , Especificidade por Substrato , Zea mays/metabolismo
2.
Braz. j. microbiol ; 49(2): 279-284, Apr.-June 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889243

RESUMO

Abstract This molecular study is the first report, to the best of our knowledge, on identification of norovirus, NoV GII.4 Sydney 2012 variants, from blue mussels collected from UK coastal waters. Blue mussels (three pooled samples from twelve mussels) collected during the 2013 summer months from UK coastal sites were screened by RT-PCR assays. PCR products of RdRP gene for noroviruses were purified, sequenced and subjected to phylogenetic analysis. All the samples tested positive for NoVs. Sequencing revealed that the NoV partial RdRP gene sequences from two pooled samples clustered with the pandemic "GII.4 Sydney variants" whilst the other pooled sample clustered with the NoV GII.2 variants. This molecular study indicated mussel contamination with pathogenic NoVs even during mid-summer in UK coastal waters which posed potential risk of NoV outbreaks irrespective of season. As the detection of Sydney 2012 NoV from our preliminary study of natural coastal mussels interestingly corroborated with NoV outbreaks in nearby areas during the same period, it emphasizes the importance of environmental surveillance work for forecast of high risk zones of NoV outbreaks.


Assuntos
Animais , Genótipo , Mytilus edulis/virologia , Norovirus/classificação , Norovirus/isolamento & purificação , Organismos Aquáticos/virologia , Análise por Conglomerados , Programas de Rastreamento , Norovirus/genética , Filogenia , Prevalência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Replicase/genética , Estações do Ano , Análise de Sequência de DNA , Homologia de Sequência , Reino Unido
3.
Braz. j. microbiol ; 48(2): 373-379, April.-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839368

RESUMO

Abstract Hepatitis E virus is responsible for acute and chronic liver infections worldwide. Swine hepatitis E virus has been isolated in Brazil, and a probable zoonotic transmission has been described, although data are still scarce. The aim of this study was to investigate the frequency of hepatitis E virus infection in pigs from a small-scale farm in the rural area of Paraná State, South Brazil. Fecal samples were collected from 170 pigs and screened for hepatitis E virus RNA using a duplex real-time RT-PCR targeting a highly conserved 70 nt long sequence within overlapping parts of ORF2 and ORF3 as well as a 113 nt sequence of ORF2. Positive samples with high viral loads were subjected to direct sequencing and phylogenetic analysis. hepatitis E virus RNA was detected in 34 (20.0%) of the 170 pigs following positive results in at least one set of screening real-time RT-PCR primers and probes. The swine hepatitis E virus strains clustered with the genotype hepatitis E virus-3b reference sequences in the phylogenetic analysis and showed close similarity to human hepatitis E virus isolates previously reported in Brazil.


Assuntos
Animais , Doenças dos Suínos/epidemiologia , Vírus da Hepatite E/isolamento & purificação , Vírus da Hepatite E/classificação , Hepatite E/veterinária , Filogenia , Suínos , Doenças dos Suínos/virologia , Brasil , RNA Viral/análise , RNA Viral/genética , Análise por Conglomerados , Prevalência , Vírus da Hepatite E/genética , Hepatite E/epidemiologia , Hepatite E/virologia , Homologia de Sequência , Análise de Sequência de DNA , Fezes/virologia , Reação em Cadeia da Polimerase em Tempo Real
4.
Braz. j. microbiol ; 48(2): 366-372, April.-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839381

RESUMO

Abstract Malignant Catarrhal Fever (MCF) was investigated in the central nervous system of cattle with neurological syndrome. Two-hundred-ninety samples were analyzed by histology, and molecular methods to detect ovine herpesvirus type 2 (OvHV-2) were optimized and validated. The qualitative polymerase chain reaction (qualitative PCR) analytical sensitivity was 101 DNA copies/µL and found 4.8% (14/290) positive for OvHV-2. The quantitative polymerase chain reaction (qPCR) analytical sensitivity was 100 DNA copy/µL and 5.9% (17/290) positivity, with 47.1% (8/17) of the positive samples presenting histological evidence of non-purulent meningo-encephalitis. The qualitative PCR products (422 bp of the ORF75 region) were sequenced and submitted to phylogenetic analysis. Identity matrices showed 100% similarity in OvHV-2 samples obtained in this study and those recovered from GenBank, corroborating other studies.


Assuntos
Animais , Filogenia , Técnicas de Diagnóstico Molecular/métodos , Herpesviridae/isolamento & purificação , Febre Catarral Maligna/diagnóstico , Febre Catarral Maligna/patologia , Brasil , Bovinos , Análise por Conglomerados , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Homologia de Sequência , Análise de Sequência de DNA , Genótipo , Herpesviridae/classificação , Herpesviridae/genética , Histocitoquímica , Microscopia
5.
Braz. j. microbiol ; 47(1): 55-62, Jan.-Mar. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-775121

RESUMO

Abstract Mercury, which is ubiquitous and recalcitrant to biodegradation processes, threatens human health by escaping to the environment via various natural and anthropogenic activities. Non-biodegradability of mercury pollutants has necessitated the development and implementation of economic alternatives with promising potential to remove metals from the environment. Enhancement of microbial based remediation strategies through genetic engineering approaches provides one such alternative with a promising future. In this study, bacterial isolates inhabiting polluted sites were screened for tolerance to varying concentrations of mercuric chloride. Following identification, several Pseudomonas and Klebsiella species were found to exhibit the highest tolerance to both organic and inorganic mercury. Screened bacterial isolates were examined for their genetic make-up in terms of the presence of genes (merP and merT) involved in the transport of mercury across the membrane either alone or in combination to deal with the toxic mercury. Gene sequence analysis revealed that the merP gene showed 86–99% homology, while the merT gene showed >98% homology with previously reported sequences. By exploring the genes involved in imparting metal resistance to bacteria, this study will serve to highlight the credentials that are particularly advantageous for their practical application to remediation of mercury from the environment.


Assuntos
Humanos , Klebsiella/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mercúrio/metabolismo , Pseudomonas/metabolismo , Poluentes Químicos da Água/metabolismo , Tolerância a Medicamentos , Genes Bacterianos , Índia , Klebsiella/efeitos dos fármacos , Klebsiella/genética , Dados de Sequência Molecular , Mercúrio/toxicidade , Pseudomonas/efeitos dos fármacos , Pseudomonas/genética , Análise de Sequência de DNA , Homologia de Sequência , Poluentes Químicos da Água/toxicidade
6.
J. med. virol ; 87(11): 1881-1889, 2015.
Artigo em Inglês | LILACS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1022299

RESUMO

World group A rotavirus (RVA) surveillance data provides useful estimates of the disease burden, however, indigenous population might require special consideration. The aim of this study was to describe the results of G­ and P­types from Brazilian native children ≤3 years. Furthermore, selected strains have been analyzed for the VP7, VP6, VP4, and NSP4 encoding genes in order to gain insight into genetic variability of Brazilian strains. A total of 149 samples, collected during 2008­2012, were tested for RVA using ELISA and PAGE, following by RT­PCR and sequencing. RVA infection was detected in 8.7% of samples (13/149). Genotype G2P[4] was detected in 2008 and 2010, G8P[6] in 2009, and G3P[8] in 2011. The phylogenetic analysis of the VP7 and VP4 genes grouped the Brazilian G2P[4] and G3P[8] strains within the lineages currently circulating in humans worldwide. However, the phylogenetic analysis of the VP6 and NSP4 from the Brazilian G2P[4] strains, and the VP7 and NSP4 from the Brazilian G3P[8] strains suggest a distant common ancestor with different animal strains (bovine, caprine, and porcine). The epidemiological and genetic information obtained in the present study is expected to provide an updated understanding of RVA genotypes circulating in the native infant population, and to formulate policies for the use of RVA vaccines in indigenous Brazilian people. Moreover, these results highlight the great diversity of human RVA strains circulating in Brazil, and an in­depth surveillance of human and animal RVA will lead to a better understanding of the complex dynamics of RVA evolution


Assuntos
Filogenia , Infecções por Rotavirus/virologia , Variação Genética , Proteínas Virais/genética , Brasil , Humanos , Ensaio de Imunoadsorção Enzimática , Dados de Sequência Molecular , Pré-Escolar , Reação em Cadeia da Polimerase , Homologia de Sequência , Análise de Sequência de DNA , Rotavirus/isolamento & purificação , Rotavirus/genética , Rotavirus/química , Evolução Molecular , Grupos Populacionais , Genótipo , Lactente
7.
ABCD arq. bras. cir. dig ; 28(1): 74-80, 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-742762

RESUMO

INTRODUCTION: Gastric bypass is today the most frequently performed bariatric procedure,but, despite of it, several complications can occur with varied morbimortality. Probably all bariatric surgeons know these complications, but, as bariatric surgery continues to spread, general surgeon must be familiarized to it and its management. Gastric bypass complications can be divided into two groups: early and late complications, taking into account the two weeks period after the surgery. This paper will focus the early ones. METHOD: Literature review was carried out using Medline/PubMed, Cochrane Library, SciELO, and additional information on institutional sites of interest crossing the headings: gastric bypass AND complications; follow-up studies AND complications; postoperative complications AND anastomosis, Roux-en-Y; obesity AND postoperative complications. Search language was English. RESULTS: There were selected 26 studies that matched the headings. Early complications included: anastomotic or staple line leaks, gastrointestinal bleeding, intestinal obstruction and incorrect Roux limb reconstruction. CONCLUSION: Knowledge on strategies on how to reduce the risk and incidence of complications must be acquired, and every surgeon must be familiar with these complications in order to achieve an earlier recognition and perform the best intervention. .


INTRODUÇÃO: O bypass gástrico é hoje o procedimento bariátrico mais realizado, mas, apesar disso, várias complicações podem ocorrer com variada morbimortalidade. Provavelmente todos os cirurgiões bariátricos conhecem essas complicações, mas como a cirurgia bariátrica continua a se espalhar, o cirurgião geral deve estar familiarizado com essas complicações e seu manuseio. As complicações do bypass gástrico podem ser divididas em dois grupos: as precoces e tardias, tendo em conta o período de duas semanas após a operação. Este artigo irá focar as precoces. MÉTODO: Foi realizada revisão da literatura utilizando as bases Medline/PubMed, Cochrane Library, SciELO, e informações adicionais sobre sites institucionais de interesse cruzando os descritores: bypass gástrico AND complicações; seguimento AND complicações; complicações pós-operatórias AND anastomose, Roux-en-Y; obesidade AND complicações pós-operatórias. A língua usada para a busca foi o inglês. RESULTADOS: Foram selecionados 26 artigos que combinavam com os descritores. As complicações imediatas foram: fístula na linha de grampeamento, sangramento gastrointestinal, obstrução intestinal e reconstrução incorreta da alça em Roux. CONCLUSÃO: O conhecimento sobre as estratégias de como reduzir o risco e incidência das complicações deve ser adquirido ao longo do tempo, e cada cirurgião deve estar familiarizado com essas complicações, a fim de reconhecê-las precocemente e realizar a melhor intervenção. .


Assuntos
Animais , Feminino , Camundongos , Linfócitos B/fisiologia , Poli(ADP-Ribose) Polimerases/fisiologia , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/genética , Apoptose/genética , Apoptose/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Sobrevivência Celular/genética , Imunoglobulina A/imunologia , /farmacologia , Camundongos Knockout , Família Multigênica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/fisiologia , Poli(ADP-Ribose) Polimerases/química , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Homologia de Sequência
8.
Braz. j. microbiol ; 45(4): 1527-1530, Oct.-Dec. 2014. ilus
Artigo em Inglês | LILACS | ID: lil-741309

RESUMO

Two Leptospira sp. isolates were obtained by the first time from goats in Brazil and characterized by sequencing rrs, rpoB and secY genes, PFGE and typing with monoclonal antibodies. Both isolates are identical and belong to Leptospira santarosai. Analysis of the rrs and the rpoB genes sequences revealed 100% identity between the goat isolates and the Bananal reference strain. When secY sequences of the two isolates were compared to each other, it was observed that they had identical sequences. However, when compared to that of the Bananal reference strain, there were 15 mismatches along the 549 bp secY sequence. In conclusion, molecular methods are increasingly useful for the characterization of leptospires and allowed to identify those isolates of caprine origin as closely related but not identical to serovar Bananal, and constitute a new type named Carioca.


Assuntos
Animais , Infecções Assintomáticas , Leptospira/isolamento & purificação , Leptospirose/veterinária , Sequência de Bases , Brasil , Proteínas de Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Polimerases Dirigidas por DNA/genética , Cabras , Leptospira/classificação , Leptospira/genética , Leptospirose/microbiologia , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência
9.
Biomédica (Bogotá) ; 34(3): 387-402, July-Sept. 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-726799

RESUMO

Introducción. El factor de transcripción asociado a la microftalmia ( Microphtalmia-Associated Transcription Factor , MITF) regula la expresión de genes específicos, pero no se conoce su expresión y su función a nivel cardiaco. Objetivos. Identificar la expresión del MITF en corazón y en cardiomiocitos aislados de cobayo, describir los cambios morfológicos asociados con su disminución y evaluar los niveles relativos de su expresión en cardiomiocitos aislados en condiciones de preacondicionamiento isquémico. Materiales y métodos. El análisis de la expresión relativa de la isoforma específica de tejido cardiaco ( heart-type MITF, MITF-H), se determinó mediante reacción en cadena de la polimerasa (PCR) en tiempo real semicuantitativa, secuenciación y Western blot . La disminución del ARNm del MITF se indujo con un ARN pequeño de interferencia ( short hairpin RNA interference , shRNAi) específico. El tamaño, el diámetro y el número de fibras musculares se evaluaron por observación directa con microscopía de luz. Resultados. Se amplificó un fragmento de 281 pb de ADNc; el análisis de la secuencia confirmó la identidad del exón 1 y la isoforma H del MITF. La interferencia del ARNm del MITF se asoció con un mayor índice cardiaco (peso corazón/peso corporal: 5,46 x 10 -3 Vs. 4,6 x 10 -3 ) y un incremento del diámetro de las fibras cardiacas (50,2±16 µm Vs. 38,7±14,7 µm; p<0,05, n=150). En los cardiomiocitos aislados en condiciones de preacondicionamiento isquémico, se observó una expresión relativa del MITF-H mayor que en los miocitos en normoxia y expuestos a lesión por isquemia simulada (80 y 100 veces más, n=5, p<0,05, n=3). Conclusión. Los resultados sugieren que el MITF-H podría estar involucrado en la hipertrofia, la respuesta al estrés por isquemia y la supervivencia de cardiomiocitos de cobayo.


Introduction: The microphthalmia -associated transcription factor ( MITF ) regulates the expression of specific genes and its cardiac expression and function is not known. Objectives: To identify the expression of MITF in hearts and isolated cardiomyocytes from Guinea pigs, to describe morphological changes associated with mRNA interference of MITF and to evaluate their relative changes in expression in isolated cardiomyocytes under ischemic preconditioning. Materials and methods: The cardiac specific isoform, MITF-H, and relative expression level analysis, was determined by semi-quantitative real time PCR, sequencing and Western blotting. Reduction of mRNA-MITF-H was induced by transduction of specific-MITF-shRNAi interference. The cardiac morphological changes, diameter and number of cardiac fibers were evaluated by direct observation and light microscopy. Results: A cDNA fragment of 281 bp was amplified from heart and isolated ventricular cardiac myocytes. Sequence analysis confirmed the identity of the isoform MITF-H, exon 1. The MITF silencing was associated with an increase in cardiac index (heart weight/body weight vs . 5.46 x 10 -3 vs 4.6 x 10 -3 ) and higher diameter of cardiac fibers (50.2±16 µ m vs 38,7±14,7 µ m p<0.05, n=150). In isolated cardiac myocytes under ischemic preconditioning we observed a higher relative expression compared with that measured in myocytes exposed to normoxia and simulated ischemia (eighty and one hundred times, p <0.05, n = 5). Conclusion. The results suggest that MITF-H isoform may be involved in Guinea pig cardiac hypertrophy, response to stress by ischemia and cardiomyocytes survival.


Assuntos
Animais , Feminino , Cobaias , Cardiomiopatia Hipertrófica/metabolismo , Fator de Transcrição Associado à Microftalmia/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Sobrevivência Celular , Células Cultivadas , Cardiomiopatia Hipertrófica/genética , DNA Complementar/genética , Regulação da Expressão Gênica , Precondicionamento Isquêmico Miocárdico , Dados de Sequência Molecular , Fator de Transcrição Associado à Microftalmia/antagonistas & inibidores , Fator de Transcrição Associado à Microftalmia/biossíntese , Fator de Transcrição Associado à Microftalmia/genética , Isquemia Miocárdica/genética , Isquemia Miocárdica/metabolismo , Miócitos Cardíacos/patologia , Oxigênio/farmacologia , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiologia , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Alinhamento de Sequência , Homologia de Sequência
10.
Braz. j. microbiol ; 45(2): 389-393, Apr.-June 2014. ilus
Artigo em Inglês | LILACS | ID: lil-723093

RESUMO

Proteolysis-resistant lipases can be well exploited by industrial processes which employ both lipase and protease as biocatalysts. A proteolysis resistant lipase from Bacillus pumilus SG2 was isolated, purified and characterized earlier. The lipase was resistant to native and commercial proteases. In the present work, we have characterized the lip gene which encodes the proteolysis-resistant lipase from Bacillus pumilus SG2. The parameters and structural details of lipase were analysed. The lip gene consisted of 650 bp. The experimental molecular weight of SG2 lipase was nearly double that of its theoretical molecular weight, thus suggesting the existence of the functional lipase as a covalent dimer. The proteolytic cleavage sites of the lipase would have been made inaccessible by dimerisation, thus rendering the lipase resistant to protease.


Assuntos
Bacillus/enzimologia , Bacillus/genética , Lipase/genética , Lipase/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Lipase/química , Dados de Sequência Molecular , Peso Molecular , Filogenia , Multimerização Proteica , Proteólise , Peptídeo Hidrolases/metabolismo , Homologia de Sequência
11.
Braz. j. microbiol ; 45(2): 603-611, Apr.-June 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-723124

RESUMO

Glucose dehydrogenase (GDH; EC 1.1. 5.2) is the member of quinoproteins group that use the redox cofactor pyrroloquinoline quinoine, calcium ions and glucose as substrate for its activity. In present study, Leclercia sp. QAU-66, isolated from rhizosphere of Vigna mungo, was characterized for phosphate solubilization and the role of GDH in plant growth promotion of Phaseolus vulgaris. The strain QAU-66 had ability to solubilize phosphorus and significantly (p < 0.05) promoted the shoot and root lengths of Phaseolus vulgaris. The structural determination of GDH protein was carried out using bioinformatics tools like Pfam, InterProScan, I-TASSER and COFACTOR. These tools predicted the structural based functional homology of pyrroloquinoline quinone domains in GDH. GDH of Leclercia sp. QAU-66 is one of the main factor that involved in plant growth promotion and provides a solid background for further research in plant growth promoting activities.


Assuntos
Enterobacteriaceae/enzimologia , Enterobacteriaceae/fisiologia , Glucose 1-Desidrogenase/genética , Fatores de Crescimento Neural , Phaseolus/crescimento & desenvolvimento , Phaseolus/microbiologia , Análise por Conglomerados , Biologia Computacional , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Glucose 1-Desidrogenase/química , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Conformação Proteica , Estrutura Terciária de Proteína , Fósforo/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Quinonas/análise , Análise de Sequência de DNA , Homologia de Sequência
12.
Braz. j. microbiol ; 44(3): 889-896, July-Sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-699822

RESUMO

Listeriosis is a disease primarily of ruminants caused by the Gram-positive bacterium Listeria monocytogenes. Ruminants either demonstrate manifestations of the encephalitic, septicemic, or reproductive form of listeriosis. The pathological and molecular findings with encephalitic listeriosis in a 5.5-month-old, male, mixed-breed goat and a 3-year-old Texel-crossed sheep from northern Paraná, Brazil are described. Clinically, the kid demonstrated circling, lateral protrusion of the tongue, head tilt, and convulsions; the ewe presented ataxia, motor incoordination, and lateral decumbency. Brainstem dysfunctions were diagnosed clinically and listeriosis was suspected. Necropsy performed on both animals did not reveal remarkable gross lesions; significant histopathological alterations were restricted to the brainstem (medulla oblongata; rhombencephalitis) and were characterized as meningoencephalitis that consisted of extensive mononuclear perivascular cuffings, neutrophilic and macrophagic microabscesses, and neuroparenchymal necrosis. PCR assay and direct sequencing, using genomic bacterial DNA derived from the brainstem of both animals, amplified the desired 174 base pairs length amplicon of the listeriolysin O gene of L. monocytogenes. Phylogenetic analyses demonstrated that the strains associated with rhombencephalitis during this study clustered with known strains of L. monocytogenes lineage I from diverse geographical locations and from cattle of the state of Paraná with encephalitic listeriosis. Consequently, these strains should be classified as L. monocytogenes lineage I. These results confirm the active participation of lineage I strains of L. monocytogenes in the etiopathogenesis of the brainstem dysfunctions observed during this study, probably represent the first characterization of small ruminant listeriosis by molecular techniques in Latin America, and suggest that ruminants within the state of Paraná were infected by the strains of the same lineage of L. monocytogenes.


Assuntos
Animais , Feminino , Masculino , Toxinas Bacterianas/genética , Doenças das Cabras/patologia , Proteínas de Choque Térmico/genética , Proteínas Hemolisinas/genética , Listeriose/veterinária , Meningoencefalite/veterinária , Doenças dos Ovinos/patologia , Brasil , Tronco Encefálico/patologia , Análise por Conglomerados , Genótipo , Cabras , Doenças das Cabras/microbiologia , Histocitoquímica , Listeria monocytogenes/genética , Listeriose/microbiologia , Listeriose/patologia , Meningoencefalite/microbiologia , Meningoencefalite/patologia , Filogenia , Reação em Cadeia da Polimerase , Homologia de Sequência , Ovinos , Doenças dos Ovinos/microbiologia
13.
Invest. clín ; 49(2): 225-237, jun. 2008. tab, graf
Artigo em Espanhol | LILACS | ID: lil-518684

RESUMO

Se realizó un estudio epidemiológico y molecular de cepas de E. histolytica y E. dispar en 428 pacientes con sintomatología gastrointestinal de diarrea, de distintos centros de salud en Cumaná, estado Sucre, Venezuela. Las muestras se procesaron a través de: examen directo con solución salina fisiológica al 0,85% y coloración temporal de lugol, coloración tricrómica y método de concentración de Ritchie, y para el asilamiento de quistes, se uso el gradiente de sacarosa. Para la detección molecular, se amplificó la subunidad pequeña de ARN 16S por Nested-Multiplex PCR. La prevalencia de E. histolytica/E. dispar por el método directo fue de 20,09 por ciento, mientras que por Ritchie se obtuvo un 13,79 por ciento y con coloración tricrómico un 12,15 por ciento. Por PCR la prevalencia para E. histolytica fue de 6,31 por ciento y de E. dispar de 4,44 por ciento, detectándose cuatro casos de infecciones mixtas. La secuenciación de los fragmentos amplificados de E. histolytica indicó un 100 por ciento de homología con las secuencias de cepas de Mérida (Venezuela), Estados Unidos, Brasil, México y del GenBank. Las infecciones por E. histolytica y E. dispar estuvieron asociadas estadísticamente con la edad, pero no con el sexo. La presencia de sangre, moco y dolor abdominal resultaron asociadas sólo en los infectados con E. histolytica. La moderada prevalencia de E. histolytica indica su carácter endémico en esta población y advierte sobre el potencial problema como factor de morbilidad y mortalidad en el estado Sucre. La frecuencia de E. dispar en esta población hace presumir que existe una sobreestimación en el diagnóstico de amibiasis con sus implicaciones clínicas y epidemiológicas y demuestra el poco conocimiento sobre las prevalencias reales de este protozoario. La PCR permitió la identificación diferencial de E. histolytica y E. dispar, así como la presencia de infecciones mixtas, por lo cual es una herramienta indispensable para estudios epidemiológicos.


Assuntos
Humanos , Masculino , Feminino , Diarreia/epidemiologia , Diarreia/parasitologia , Entamoeba histolytica/parasitologia , Enteropatias Parasitárias/epidemiologia , Homologia de Sequência
14.
Biol. Res ; 39(2): 367-376, 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-432438

RESUMO

Botrytis cinerea is a filamentous plant pathogen of a wide range of plant species, and its infection may cause enormous damage both during plant growth and in the post-harvest phase. We have constructed a cDNA library from an isolate of B. cinerea and have sequenced 11,482 expressed sequence tags that were assembled into 1,003 contigs sequences and 3,032 singletons. Approximately 81% of the unigenes showed significant similarity to genes coding for proteins with known functions: more than 50% of the sequences code for genes involved in cellular metabolism, 12% for transport of metabolites, and approximately 10% for cellular organization. Other functional categories include responses to biotic and abiotic stimuli, cell communication, cell homeostasis, and cell development. We carried out pair-wise comparisons with fungal databases to determine the B. cinerea unisequence set with relevant similarity to genes in other fungal pathogenic counterparts. Among the 4,035 non-redundant B. cinerea unigenes, 1,338 (23%) have significant homology with Fusarium verticillioides unigenes. Similar values were obtained for Saccharomyces cerevisiae and Aspergillus nidulans (22% and 24%, respectively). The lower percentages of homology were with Magnaporthe grisae and Neurospora crassa (13% and 19%, respectively). Several genes involved in putative and known fungal virulence and general pathogenicity were identified. The results provide important information for future research on this fungal pathogen.


Assuntos
Botrytis/genética , Etiquetas de Sequências Expressas , Botrytis/patogenicidade , Regulação Fúngica da Expressão Gênica/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência , Fatores de Virulência/genética
15.
Recife; s.n; 2005. 60,[13] p. mapas, tab, graf.
Tese em Português | LILACS | ID: lil-527798

RESUMO

A dengue é a infecção viral transmitida por vetores artrópodes (arbovirose) mais importante no mundo e que re-emergiu nas ultimas décadas e acomete mais de 50 milhões de pessoas a cada ano em áreas tropicais e sub-tropicais do planeta (OMS, 1999). O diagnóstico molecular do vírus dengue é convencionalmente realizado utilizando a técnica proposta por Lanciotti et al, 1992, no entanto alguns autores já relataram dificuldades na detecção de pelo mesmo um sorotipo viral utilizando esta técnica. No Laboratório de Virologia e Terapia Experimental do Centro de Pesquisas Aggeu Magalhães foram realizadas no ano de 2003 análises moleculares baseadas na técnica de Lanciotti em amostras de soro de pacientes com suspeita de infecção pelo vírus dengue. Nas amostras analisadas e que apresentaram sorologia positiva para o vírus o teste apenas conseguiu detectar 20 por cento delas. Surgiu à hipótese de o teste proposto por Lanciotti (teste baseado na técnica de Nested-PCR), não estar detectando todas as linhagens do vírus dengue circulantes no Recife, pois a variabilidade genética a que estes vírus estão expostos pode ter sido imposta a seqüências de nucleotídeos da região do genoma viral que foi alvo do desenho dos primers. Neste trabalho foi realizado uma otimização da técnica de Lanciotti quanto a síntese de cDNA e condições da reação de PCR e foram 10 novas amostras foram detectadas dentre aquelas anteriormente testadas. Foi realizado um estudo das seqüências genômicas dos sorotipos dengue e os dados apresentados sugerem que o sorotipo dengue 2 é o que apresenta uma maior variabilidade genética, como demonstrado por Rico-Hesse (1989) e Holmes (2003). Os resultados das análises de homologia entre as seqüências virais e as seqüências dos primers sugerem que as linhagens dos sorotipos virais dengue apresentam pontos de mutações em suas seqüências em relação às seqüências dos primers e as mutações muitas vezes ocorrem em posições que podem comprometer o funcionamento do teste diagnóstico. Uma nova abordagem molecular de diagnóstico, inicialmente para o sorotipo viral 3, foi proposta baseadas na técnica de hemi-nested PCR em tubo único para tentar aumentar a detecção do vírus dengue.


Assuntos
Dengue/diagnóstico , Variação Genética , Vírus da Dengue/genética , Aedes/virologia , DNA Complementar/síntese química , Reação em Cadeia da Polimerase , Primers do DNA/análise , Primers do DNA/genética , Homologia de Sequência , Técnicas de Diagnóstico Molecular/métodos
16.
Genet. mol. res. (Online) ; 3(1): 167-180, Mar. 2004.
Artigo em Inglês | LILACS | ID: lil-417575

RESUMO

Chromobacterium violaceum is a Gram-negative beta-proteobacterium that inhabits a variety of ecosystems in tropical and subtropical regions, including the water and banks of the Negro River in the Brazilian Amazon. This bacterium has been the subject of extensive study over the last three decades, due to its biotechnological properties, including the characteristic violacein pigment, which has antimicrobial and anti-tumoral activities. C. violaceum promotes the solubilization of gold in a mercury-free process, and has been used in the synthesis of homopolyesters suitable for the production of biodegradable polymers. The complete genome sequence of this organism has been completed by the Brazilian National Genome Project Consortium. The aim of our group was to study the DNA repair genes in this organism, due to their importance in the maintenance of genomic integrity. We identified DNA repair genes involved in different pathways in C. violaceum through a similarity search against known sequences deposited in databases. The phylogenetic analyses were done using programs of the PHILYP package. This analysis revealed various metabolic pathways, including photoreactivation, base excision repair, nucleotide excision repair, mismatch repair, recombinational repair, and the SOS system. The similarity between the C. violaceum sequences and those of Neisserie miningitidis and Ralstonia solanacearum was greater than that between the C. violaceum and Escherichia coli sequences. The peculiarities found in the C. violaceum genome were the absence of LexA, some horizontal transfer events and a large number of repair genes involved with alkyl and oxidative DNA damage


Assuntos
Chromobacterium/genética , Proteínas de Bactérias/genética , Reparo do DNA/genética , Homologia de Sequência , Bases de Dados Genéticas , Filogenia , Pareamento Incorreto de Bases/genética , Recombinação Genética , Resposta SOS em Genética/genética
17.
Braz. j. med. biol. res ; 35(3): 369-375, Mar. 2002. ilus, tab
Artigo em Inglês | LILACS | ID: lil-304663

RESUMO

The main objective of the present study was to assess the specificity and sensitivity of a modified assay using short synthetic peptides of the V3 region of HIV-1 gp120, which is the main target for neutralizing antibodies. Results from an enzyme immunoassay (EIA) employing a panel of synthetic peptides of HIV-1 subtypes and using urea washes to detect high avidity antibodies (AAV3) were compared with those obtained by the heteroduplex mobility assay and DNA sequencing. The EIA correctly typed 100 percent of subtype B (sensitivity = 1.0; specificity = 0.95), 100 percent of HIV-1 E samples (sensitivity = 1.0; specificity = 1.0), and 95 percent of subtype C specimens (sensitivity = 0.95; specificity = 0.94). In contrast, only 50 percent of subtype A (sensitivity = 0.5; specificity = 0.95), 60 percent of subtype D (sensitivity = 0.6; specificity = 1.0), and 28 percent of subtype F samples (sensitivity = 0.28; specificity = 0.95) were correctly identified. This approach was also able to discriminate in a few samples antibodies from patients infected with B variants circulating in Brazil and Thailand that reacted specifically. The assays described in this study are relatively rapid and simple to perform compared to molecular approaches and can be used to screen large numbers of serum or plasma samples. Moreover, the classification in subtypes (genotypes) may overestimate HIV-1 diversity and a classification into serotypes, based on antigenic V3 diversity or another principal neutralization domain, may be more helpful for vaccine development and identification of variants


Assuntos
Humanos , Afinidade de Anticorpos , Anticorpos Anti-HIV , Proteína gp120 do Envelope de HIV , Infecções por HIV , HIV-1 , Técnicas Imunoenzimáticas , Sequência de Aminoácidos , Sequência de Bases , Anticorpos Anti-HIV , Infecções por HIV , HIV-1 , Dados de Sequência Molecular , Sensibilidade e Especificidade , Homologia de Sequência , Sorologia , Sorotipagem
18.
Medicina (B.Aires) ; 62(4): 327-323, 2002. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-317323

RESUMO

In the last years research on the possible viral etiology of human breast cancer has been revised. Previous studies have demonstrated the presence of a Mouse Mammary Tumor Virus (MMTV) env gene-like sequence in about 38% of breast cancers from American and Italian women; these sequences are generally absent in other tumors and in normal mammary tissue. In the present study we have analyzed the presence of a 250-bp sequence of the MMTV env gene in breast cancer biopsies from Argentine patients. The retroviral fragment was present in 31% (23/74) of the tumors, only in one normal mammary tissue and in none of the fibroadenomas analYzed. Peripheral blood mononuclear cells (PBMC) from 46 cancer patients were also analyzed; the sequence was found in 17% (2/12) of the PBMC from env positive tumor patients and in 3% (1/34) of the env negatives. The results from Argentine samples are similar to those from USA and Italy, where the breast cancer incidence is alike. These findings support the hypothesis of a viral agent involved in the genesis of this neoplasia and encourage the continuation of these studies


Assuntos
Humanos , Animais , Feminino , Camundongos , Neoplasias da Mama , Genes env , Vírus do Tumor Mamário do Camundongo , Infecções por Retroviridae , Infecções Tumorais por Vírus , Argentina , Sequência de Bases , Homologia de Sequência
19.
Mem. Inst. Oswaldo Cruz ; 96(3): 357-364, Apr. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-282845

RESUMO

Cry11Bb is an insecticidal crystal protein produced by Bacillus thuringiensis subsp. medellin during its stationary phase; this Â-endotoxin is active against dipteran insects and has great potential for mosquito borne disease control. Here, we report the first theoretical model of the tridimensional structure of a Cry11 toxin. The tridimensional structure of the Cry11Bb toxin was obtained by homology modelling on the structures of the Cry1Aa and Cry3Aa toxins. In this work we give a brief description of our model and hypothesize the residues of the Cry11Bb toxin that could be important in receptor recognition and pore formation. This model will serve as a starting point for the design of mutagenesis experiments aimed to the improvement of toxicity, and to provide a new tool for the elucidation of the mechanism of action of these mosquitocidal proteins


Assuntos
Bacillus thuringiensis/química , Toxinas Bacterianas/química , Insetos/química , Modelos Teóricos , Homologia de Sequência
20.
Rev. cuba. med. trop ; 50(4): 267-269, Dic. 1998.
Artigo em Espanhol | LILACS | ID: lil-629305

RESUMO

Se presenta la caracterización genómica de la cepa de efecto citopático ligero por secuenciación nucleotídica. Se logró secuenciar el 90 % de la cepa de efecto citopático ligero, se mostró una estrecha relación con los Coxsackie A9 y las mayores mutaciones ocurrieron en la región del genoma que codifica para las proteínas estructurales. De ahí que se pueda considerar una variante de Coxsackie A9 no reportada antes.


The genomic characterization of the strain of light cytopathic effect by nucleotide sequence is presented. It was possible to sequence 90 % of the strain of light cytopathic effect. A close relationship with Coxsackie A9 was observed. The greatest mutations occurred in the region of the genoma that codifies for the structural proteins. Therefore, it may be considered as a variant of Coxsackie A9 never reported before.


Assuntos
Animais , Enterovirus/genética , Genoma Viral , Sequência de Bases , Chlorocebus aethiops , Cuba , Efeito Citopatogênico Viral , Enterovirus/patogenicidade , Mutação , Reação em Cadeia da Polimerase , Homologia de Sequência , Células Vero , Cultura de Vírus
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