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1.
Mol Hum Reprod ; 24(11): 556-563, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30376129

RESUMO

STUDY QUESTION: Can the mediator complex subunit 12 (MED12) mutation and high mobility group AT-hook 2 (HMGA2) overexpression co-occurrence be explained by the alternative mechanism of HMGA2 dysregulation in uterine leiomyomas (UL)? SUMMARY ANSWER: The co-occurrence of MED12 mutation and HMGA2 overexpression, and a negative correlation of five validated or predicted microRNAs that target HMGA2 were reported. WHAT IS KNOWN ALREADY: The recent stratification of UL, according to recurrent and mutually exclusive genomic alterations affecting HMGA2, MED12, fumarate hydratase (FH) and collagen type IV alpha 5-alpha 6 (COL4A5-COL4A6) pointed out the involvement of distinct molecular pathways. However, the mechanisms of regulation involving these drivers are poorly explored. STUDY DESIGN, SIZE, DURATION: A total of 78 UL and 34 adjacent normal myometrium (NM) tissues was collected from 56 patients who underwent hysterectomies at a single institution. The patients were treated at the Department of Gynecology and Obstetrics, School of Medicine, Sao Paulo State University, Botucatu, SP, Brazil, from October 1995 to February 2004. PARTICIPANTS/MATERIALS, SETTING, METHODS: Gene expression profiling was evaluated from fresh frozen tissues and compared with MED12 mutations at exon 2. In addition, RT-qPCR was applied to evaluate the expression levels of HMGA2 and their predictive miRNA regulators: hsa-let-7a, miR-26a, miR-26b, mir-93 and mir-106b. MAIN RESULTS AND THE ROLE OF CHANCE: An unsupervised hierarchical clustering analysis revealed two main clusters with one of them (26 of 42 UL) showing an enrichment of MED12 mutated cases (18 of 26 UL). Increased expression levels of HMGA2 were observed in both clusters, including cases with MED12 mutation (cluster 1:18 UL). A significant HMGA2 overexpression (P < 0.001) in UL in comparison with NM was found. Five miRNAs predicted to regulate HMGA2 were significantly downregulated (P < 0.001) and negatively correlated to HMGA2 expression levels (P < 0.05) in UL. LIMITATIONS REASONS FOR CAUTION: An in vivo functional study was not performed to validate the microRNAs and HMGA2 interaction due to technical limitations. WIDER IMPLICATIONS OF THE FINDINGS: HMGA2 overexpression was detected in a significant number of MED12 mutated ULs, suggesting that these alterations coexist. Furthermore, five miRNAs were described as potential regulators of HMGA2 expression in UL. LARGE-SCALE DATA: Data available in the Gene Expression Omnibus GSE42939. STUDY FUNDING AND COMPETING INTEREST(S): This study was supported by grants from Fundação de Amparo a Pesquisa do Estado de São Paulo (# 2008/58835-2) and Conselho Nacional de Pesquisa (# 485032/2007-4), Brazil. The authors declared having no conflicts of interest.


Assuntos
Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Leiomioma/metabolismo , MicroRNAs/metabolismo , Neoplasias Uterinas/metabolismo , Adulto , Éxons/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Técnicas In Vitro , Leiomioma/genética , MicroRNAs/genética , Pessoa de Meia-Idade , Mutação , Neoplasias Uterinas/genética
2.
Rev. bras. ciênc. mov ; 26(3): 123-133, jul.-set.2018. ilus
Artigo em Português | LILACS | ID: biblio-966901

RESUMO

O objetivo deste estudo foi identificar o significado atribuído ao lazer por dois grupos de espeleologia nas relações socioambientais durante a prática do caving. Esta é uma pesquisa de abordagem qualitativa desenvolvida com 30 indivíduos pertencentes ao Espeleogrupo Peter Lund e à Associação de Agentes Ambientais do Vale do Peruaçu. Os dados foram coletados através de entrevistas semiestruturadas, processados no IRAMUTEQ e a análise de similitude feita. Os resultados obtidos indicaram uma associação entre lazer-caverna e lazer-atividade. O lazer pode ser entendido como uma atividade prática em ambiente de caverna realizada no tempo livre. Ele promove o prazer individual e coletivo, um contato com a natureza que proporciona sensações e bem-estar, aventura e descoberta, por meio do caving, na contemplação do ambiente cavernícola. O lazer pode ser entendido como uma atividade prática em ambiente de caverna realizada no tempo livre pelos seus praticantes. Ele promove o prazer individual e coletivo, um contato com a natureza que proporciona sensações e bem-estar, aventura e descoberta, por meio do caving, na contemplação do ambiente cavernícola....(AU)


The objective of this study was to identify the meaning attributed to leisure by two groups of caving in the socioenvironmental relations during the practice of caving. This is a qualitative approach research developed with 30 individuals belonging to the Peter Lund Speleogrupo and to the Association of Environmental Agents of the Vale do Peruaçu. The data were collected through semi-structured interviews, processed in IRAMUTEQ and the similitude analysis made. The results indicated an association between leisure-cave and leisure-activity. Leisure can be understood as a practical activity in cave environment held in free time. It promotes individual and collective pleasure, a contact with nature that provides sensations and well-being, adventure and discovery, through caving, in contemplation of the cave environment. Leisure can be understood as a practical activity in a cave environment held in free time by its practitioners. It promotes individual and collective pleasure, a contact with nature that provides sensations and well-being, adventure and discovery, through caving, in contemplation of the cave environment....(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Educação Física e Treinamento , Cavernas , Atividades de Lazer
3.
Environ Microbiol Rep ; 10(3): 337-343, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29611897

RESUMO

Magnetotactic bacteria are a multi-phyletic group of bacteria that synthesize membrane-bound magnetic minerals. Understanding the preservation of these minerals in various environments (e.g., with varying oxygen concentrations and iron supply) is important for understanding their role as carriers of primary magnetizations in sediments and sedimentary rocks. Here we present X-ray near edge structure (XANES) spectra for Fe in magnetotactic bacteria samples from recent sediments to assess surface oxidation and crystal structure changes in bacterial magnetite during early burial. Our results are compared with a XANES spectrum of cultivated Magnetofaba australis samples, and with magnetic properties, and indicate that oxidation of magnetite to maghemite increases with depth in the sediment due to longer exposure to molecular oxygen. These results are relevant to understanding magnetic signatures carried by magnetofossils in oxic sediments and sedimentary rocks of different ages.


Assuntos
Alphaproteobacteria/metabolismo , Organismos Aquáticos/metabolismo , Óxido Ferroso-Férrico/metabolismo , Magnetossomos/metabolismo , Alphaproteobacteria/efeitos da radiação , Organismos Aquáticos/efeitos da radiação , Compostos Férricos/análise , Compostos Férricos/metabolismo , Óxido Ferroso-Férrico/análise , Magnetossomos/química , Oxirredução , Síncrotrons , Espectroscopia por Absorção de Raios X
4.
Genet Mol Res ; 14(3): 8181-200, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26345744

RESUMO

Gene expression related to drought response in the leaf tissues of two Brazilian upland cultivars, the drought-tolerant Douradão and the drought-sensitive Primavera, was analyzed. RNA-seq identified 27,618 transcripts in the Douradão cultivar, with 24,090 (87.2%) homologous to the rice database, and 27,221 transcripts in the Primavera cultivar, with 23,663 (86.9%) homologous to the rice database. Gene-expression analysis between control and water-deficient treatments revealed 493 and 1154 differentially expressed genes in Douradão and Primavera cultivars, respectively. Genes exclusively expressed under drought were identified for Douradão, including two genes of particular interest coding for the protein peroxidase precursor, which is involved in three distinct metabolic pathways. Comparisons between the two drought-exposed cultivars revealed 2314 genes were differentially expressed (978 upregulated, 1336 downregulated in Douradão). Six genes distributed across 4 different transcription factor families (bHLH, MYB, NAC, and WRKY) were identified, all of which were upregulated in Douradão compared to Primavera during drought. Most of the genes identified in Douradão activate metabolic pathways responsible for production of secondary metabolites and genes coding for enzymatically active signaling receptors. Quantitative PCR validation showed that most gene expression was in agreement with computational prediction of these transcripts. The transcripts identified here will define molecular markers for identification of Cis-acting elements to search for allelic variants of these genes through analysis of polymorphic SNPs in GenBank accessions of upland rice, aiming to develop cultivars with the best combination of these alleles, resulting in materials with high yield potential in the event of drought during the reproductive phase.


Assuntos
Adaptação Fisiológica/genética , Secas , Ecótipo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Oryza/genética , Oryza/fisiologia , Clima Tropical , Sequência de Bases , Regulação para Baixo/genética , Perfilação da Expressão Gênica , Ontologia Genética , Redes e Vias Metabólicas/genética , Anotação de Sequência Molecular , Folhas de Planta/genética , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de RNA , Estresse Fisiológico/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/genética
5.
Rev. bras. plantas med ; Rev. bras. plantas med;15(3): 397-404, 2013. ilus
Artigo em Português | LILACS | ID: lil-684157

RESUMO

A espécie Garcinia brasiliensis Mart. (Clusiaceae), nativa da região Amazônica e cultivada em todo o território brasileiro, vem sendo bastante estudada devido seu potencial farmacológico, porém são escassos estudos que tratam da caracterização farmacobotânica desta espécie. Considerando as propriedades terapêuticas para tornar-se um medicamento fitoterápico, o presente trabalho teve como objetivos estudar a anatomia e histoquímica da folha e do pecíolo e elaborar dados macroscópicos e microscópicos que forneçam características marcantes para sua identificação além de dar subsídios para a análise farmacognóstica no controle de qualidade da droga vegetal. O material vegetal foi fixado e submetido às técnicas usuais de microscopia de luz e a testes histoquímicos. As folhas de G. brasiliensis são opostas, simples, descolores, forma elíptica com nervação peninérvia. As células epidérmicas, em vista frontal, apresentam contorno sinuoso e estômatos paracíticos somente na face abaxial. O mesofilo é dorsiventral, a nervura central apresenta contorno biconvexo e feixe vascular em forma de semi-arco fechado envolto por bainha esclerenquimática. Inclusões inorgânicas de cristais na forma de drusas e orgânicas representadas por compostos fenólicos e grãos de amidos estão dispersos ao longo de toda lâmina foliar e pecíolo. Observa-se com frequência a presença de canais secretores preenchidos por um conteúdo lipídico dispersos pelo parênquima fundamental e próximos aos feixes vasculares. Estes dados fornecem subsídios para o controle de qualidade da matéria-prima utilizada para a produção de fitoterápicos.


The Garcinia brasiliensis Mart. (Clusiaceae) species, native of the Amazon region and cultivated throughout the Brazilian territory, has been widely studied due to its pharmacological potential, but there are few studies dealing with the pharmacobotanic characterization of this species. Considering the therapeutic properties in order to become an herbal medicine, the present paper had the purpose of studying the anatomical and histochemical characterization of the leaf and petiole, as well as producing macroscopic and microscopic data that provide important characteristics for its identification, in addition to providing subsidies for the pharmacognostical analysis in order to offer elements for the quality assurance of the drug. The botanical material was prepared through the usual optical and histochemical microtechniques. The leaves of G. brasiliensis are simple, opposed, colorless, and they show an elliptical shape. As seen from the front, the epidermal cells have a sinuous contour, and paracytic stomata occur on the low surface. The leaves are hipostomatic and dorsiventral with heterogeneous mesophile. The mesophile is dorsiventral, the central midrib shows a biconvex contour and vascular system in a semi-closed arch shape surrounded by a sclerenchymatic sheath. Inorganic inclusions of crystals in the shape of druses, and organic inclusions represented by phenolic compounds and starch grains are found throughout the leaf blade and petiole. It is common to find secretory canals filled with a lipid content dispersed throughout the parenchyma and near the vascular bundles. These data support the quality assurance of the elements used to produce herbal medicines.


Assuntos
Folhas de Planta/anatomia & histologia , Garcinia/genética , Clusiaceae/classificação , Anatomia
6.
Toxicol In Vitro ; 26(4): 585-94, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22386657

RESUMO

In this study, the cytotoxicity, genotoxicity and early ROS generation of 2,2-dimethyl-(3H)-3-(N-3'-nitrophenylamino)naphtho[1,2-b]furan-4,5-dione (QPhNO(2)) were investigated and compared with those of its precursor, nor-beta-lapachone (nor-beta), with the main goal of proposing a mechanism of antitumor action. The results were correlated with those obtained from electrochemical experiments held in protic (acetate buffer pH 4.5) and aprotic (DMF/TBABF(4)) media in the presence and absence of oxygen and with those from dsDNA biosensors and ssDNA in solution, which provided evidence of a positive interaction with DNA in the case of QPhNO(2). QPhNO(2) caused DNA fragmentation and mitochondrial depolarization and induced apoptosis/necrosis in HL-60 cells. Pre-treatment with N-acetyl-l-cysteine partially abolished the observed effects related to the QPhNO(2) treatment, including those involving apoptosis induction, indicating a partially redox-dependent mechanism. These findings point to the potential use of the combination of pharmacology and electrochemistry in medicinal chemistry.


Assuntos
Antineoplásicos/farmacologia , Benzofuranos/farmacologia , Naftoquinonas/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Células HL-60 , Humanos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
7.
Toxicol Sci ; 81(1): 172-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15201443

RESUMO

Methylmercury (MeHg) is a highly neurotoxic compound and several studies have reported intoxication signs in children whose mothers were exposed to this environmental toxicant. Although it is well established that the in utero exposure to MeHg causes neurological deficits in animals and humans, there is no evidence of the exclusive contribution of lactational exposure to MeHg as a possible cause of neurotoxicity in the offspring. In this study, we investigated the exclusive contribution of MeHg exposure through maternal milk on biochemical parameters related to the glutamatergic homeostasis (glutamate uptake by slices) and to the oxidative stress (total and nonprotein sulfhydryl groups, nonprotein hydroperoxides, glutathione peroxidase and catalase activities) in the cerebellum of suckling mice (Swiss albino). The same parameters were also evaluated in the cerebellum of mothers. Our results showed, for the first time, that lactational exposure to MeHg caused a high percent of inhibition (50%) on glutamate uptake by cerebellar slices in pups. Contrarily, this effect was not observed in mothers, which were submitted to a direct oral exposure to MeHg (15 mg/l in drinking water). In addition, behavioral/functional changes were observed in the weaning mice exposed to MeHg. It was observed an increase in the levels of nonprotein hydroperoxides in cerebellum, and this increase was negatively correlated to the glutamate uptake by cerebellar slices. This study indicates that (1) the exposure of lactating mice to MeHg causes inhibition of the glutamate uptake by cerebellar slices in the offspring; (2) this inhibitory effect seems to be related to increased levels of hydroperoxide.


Assuntos
Cerebelo/fisiopatologia , Ácido Glutâmico/fisiologia , Compostos de Metilmercúrio/intoxicação , Leite/química , Síndromes Neurotóxicas/fisiopatologia , Animais , Animais Lactentes , Antioxidantes/metabolismo , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Cerebelo/enzimologia , Cerebelo/metabolismo , Feminino , Ácido Glutâmico/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Técnicas In Vitro , Masculino , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Síndromes Neurotóxicas/enzimologia , Síndromes Neurotóxicas/psicologia , Compostos de Sulfidrila/metabolismo
8.
Bioelectrochemistry ; 63(1-2): 353-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15110302

RESUMO

Because redox properties are central to bioreductive drug activity and selectivity, six 2-methyl-5-nitroimidazole, substituted at the N1-ethyl side chain with I, Br, Cl, OAc, OMs and NH(3)(+) were synthesized and submitted to cyclic voltammetry and electrolyses, in order to define their electrodic reduction mechanism, in aprotic [dimethylsulphoxide (DMSO)+0.1 mol l(-1) tetrabuthylammonium perchlorate (TBAP)] and phosphate-buffered media, on glassy carbon electrode, in comparison with metronidazole. Three of these compounds, namely, the iodo, bromo and ammonium salt derivatives showed significant anti-Helicobacter pylori (strain resistant to metronidazole) activity. All the cyclic voltammograms (CV), in aprotic medium, are similar to the one for metronidazole, except for -I, -Br and -NH(3)(+) derivatives. The CV of the N1-ethylhalide (-I, -Br) 5-nitroimidazole showed more intense and irreversible first waves, even at faster sweep rates (nu<2 V s(-1)). The absence of the first wave anodic counterpart, along with analysis of the dependence of E(p), I(p) and other parameters with nu, and results from electrolysis (consumption of two electrons) showed the process to be an ECE system, with halide release, after uptake of two electrons. This behaviour represents a case of dissociative electron transfer (ET). For the ammonium salt, self-protonation mechanism was evident. The facility of reduction represented by the first wave potential and concerning the substituents is NH(3)(+)>Br>I>Cl>OMs>OH>OAc. In aqueous phosphate-buffered medium, the electrochemical behaviour of all the compounds is similar to the one of metronidazole, represented by a unique and irreversible 4e(-)/4H(+) wave. The order of reduction ease is NH(3)(+)>Br approximately OMs>I>OH>OAc. Aprotic medium allows a better discrimination between the substituents. Concerning biological activity, despite the impossibility of establishing a correlation, it has been observed that the more electrophilic compounds showed better anti-H. pylori activity.


Assuntos
Antibacterianos/química , Eletroquímica/métodos , Helicobacter pylori/efeitos dos fármacos , Metronidazol/análise , Metronidazol/química , Antibacterianos/análise , Antibacterianos/farmacologia , Dimetil Sulfóxido/química , Avaliação Pré-Clínica de Medicamentos/métodos , Eletrodos , Concentração de Íons de Hidrogênio , Metronidazol/análogos & derivados , Oxirredução , Compostos de Amônio Quaternário/química , Relação Estrutura-Atividade
9.
Ann Thorac Surg ; 76(6): 1962-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14667622

RESUMO

BACKGROUND: We analyzed our 22 years of experience with extraanatomic bypass grafting for repair of aortic arch coarctation in adults. Results from early and midterm follow-up with clinical evaluation and magnetic resonance angiography are reported. METHODS: Between November 1979 and December 2001, 18 consecutive patients aged 18 to 61 years (mean, 31.8 +/- 13.3 years) underwent extraanatomic bypass grafting to repair coarctation of the aortic arch. Six patients (33.3%) had recoarctation after previous repair through a left thoracotomy, and 3 (16.7%) had associated cardiac diseases. The operative technique used in all patients was ascending aorta-to-descending thoracic aorta bypass with a polyethylene terephthalate fiber (Dacron) graft through a median sternotomy and posterior pericardial approach. RESULTS: Follow-up was completed in all patients, with a mean duration of 5.6 +/- 5.7 years (range, 12 months to 22 years). The follow-up interval exceeded 10 years in 5 patients. No neurologic complications, early or late mortality, late reoperations, or graft complications occurred. Six patients (33.3%) had mild hypertension. All patients were asymptomatic with patent Dacron grafts confirmed by echocardiography. Magnetic resonance angiography, performed in 15 (83.3%) patients, revealed that the Dacron grafts were still patent at a mean interval of 4.0 +/- 6.2 years (range, 5 days to 22 years) after repair. CONCLUSIONS: Extraanatomic ascending aorta-to-descending thoracic aorta bypass grafting for repair of aortic arch coarctation in adults is safe, with low morbidity and no mortality. The favorable midterm results indicate this technique is a safe and less invasive means of repairing aortic arch coarctation or recoarctation in adults.


Assuntos
Aorta Torácica/cirurgia , Coartação Aórtica/cirurgia , Implante de Prótese Vascular , Prótese Vascular , Esterno/cirurgia , Adolescente , Adulto , Coartação Aórtica/diagnóstico , Implante de Prótese Vascular/métodos , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
10.
Am J Trop Med Hyg ; 64(5-6): 298-302, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11463121

RESUMO

Schistosomiasis mansoni infection that occurs concurrently with Staphylococcus aureus bacteremia favors the formation of pyogenic liver abscess. The present experimental study in mice evaluated the following aspects of the relationship between infection with Schistosoma mansoni and liver abscess caused by S. aureus: a) the role of the eggs of S. mansoni in the genesis of the abscesses; b) the influence of different phases of schistosomiasis in the development of liver abscesses; and c) the effect of the treatment of schistosomiasis on the development of the abscesses. Macroscopic and histopathological study showed multiple liver abscesses around granulomas of S. mansoni in the acute and chronic phases of schistosomiasis. Treatment of acute schistosomiasis before experimentally-induced bacteremia did not prevent the formation of liver abscess. The study findings indicate that granulomas around S. mansoni eggs and worms lodged in the liver provide a focus and substrate for pyogenic abscesses caused by S. aureus.


Assuntos
Abscesso Hepático/patologia , Esquistossomose/patologia , Doença Aguda , Animais , Doença Crônica , Abscesso Hepático/complicações , Abscesso Hepático/tratamento farmacológico , Masculino , Camundongos , Oxamniquine/uso terapêutico , Esquistossomose/complicações , Esquistossomose/tratamento farmacológico , Esquistossomicidas/uso terapêutico , Infecções Estafilocócicas/complicações
11.
Bioorg Med Chem ; 9(3): 659-64, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11310601

RESUMO

Abstract-Molluscicidal bioassays and electrochemical studies (measurement of first wave reduction potential, Epcl) were performed on several synthetic nitroaromatics, in relation to possible correlation between biological activity, redox potential and structural effects. Five of them presented a significant molluscicidal activity on Biomphalaria glabrata (LD50 < 20 ppm). The Epc1 values ranged from -0.532 to -0.857 V versus Ag/AgCl (0.1 M) (-0.260 to -0.585 V versus NHE), all of them, in the favorable range for reduction in vivo. Data comparison between Epc1 and molluscicidal activity indicates that the presence of the electroactive nitro group is important for the biological activity. Correlation with redox potential, however, was not evident. Structural effects seem to be the most important parameter. Higher activity is noticeable for phenols, including the para-nitro azo or hydrazo-containing compounds. No activity was observed for compounds having the benzylic substituent in meta position to the nitro group. These results suggest that activity undoubtedly involves more than reduction characteristics and that the possible formation of electrophilic species, after nitro reduction, can play an important role in molluscicidal activity against B. glabrata.


Assuntos
Antiparasitários/farmacologia , Moluscos/efeitos dos fármacos , Nitrocompostos/farmacologia , Nitrobenzenos/farmacologia , Animais , Antiparasitários/síntese química , Antiparasitários/química , Eletroquímica , Concentração Inibidora 50 , Nitrocompostos/síntese química , Nitrobenzenos/síntese química , Nitrobenzenos/química , Oxirredução , Esquistossomose mansoni/tratamento farmacológico , Caramujos/efeitos dos fármacos , Relação Estrutura-Atividade
12.
Nature ; 406(6792): 151-9, 2000 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-10910347

RESUMO

Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer.


Assuntos
Genoma Bacteriano , Plantas/microbiologia , Pseudomonadaceae/genética , Análise de Sequência de DNA , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Transporte Biológico , Mapeamento Cromossômico , Citrus/microbiologia , Reparo do DNA , DNA Bacteriano , Metabolismo Energético , Dados de Sequência Molecular , Plantas Tóxicas , Biossíntese de Proteínas , Pseudomonadaceae/metabolismo , Pseudomonadaceae/patogenicidade , Nicotiana/microbiologia , Transcrição Gênica , Virulência/genética
13.
Hum Biol ; 71(1): 111-21, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9972102

RESUMO

Cystic fibrosis (CF) is an autosomal recessive disease caused by at least 750 different mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The frequency of the most common mutation (DF508) in Brazilian patients of European origin is 47%. To determine the frequency of 4 other common CF mutations (G542X, G551D, R553X, and N1303K) in Brazilian patients of European origin, we used direct polymerase chain reaction (PCR) amplification of DNA obtained from dried blood spots on Guthrie cards. The DNA came from 247 non-DF508 chromosomes from 172 Brazilian CF patients ascertained from 5 different states of Brazil. The results show that the 4 mutations account for 17% of the non-DF508 alleles and only 9% of the total number of Brazilian CF alleles. Overall, the frequency of each mutation is different from northern European and North American populations but similar to southern European populations, mainly the Italian and Spanish populations. When Brazilian patients of European origin are grouped according to state of birth, the frequencies of the mutations are significantly different between southern and southeastern states of Brazil. Therefore there are serious implication for risk assessment of DNA-based tests in heterogeneous populations such as Brazilians. Further studies are needed to identify the remaining 44% of CF mutations for the different populations and regions of Brazil.


Assuntos
Fibrose Cística/epidemiologia , Fibrose Cística/genética , DNA Satélite/análise , Frequência do Gene , Heterogeneidade Genética , Mutação/genética , Adolescente , Adulto , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Europa (Continente)/etnologia , Humanos , Lactente , Masculino , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Estudos de Amostragem , Estudos Soroepidemiológicos
14.
Hum Biol ; 69(4): 499-508, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9198309

RESUMO

We have used PCR amplification of DNA obtained from Guthrie cards to identify the DF508 mutation and correlate it with the allele frequencies at two polymorphic loci (XV-2C and KM-19) closely linked to the cystic fibrosis gene. The DNA came from 193 white Brazilian families affected by cystic fibrosis and living in five different states of Brazil. The distribution of the haplotypes derived from the DF508 and non-DF508 XV-2C/KM-19 genotypes indicates that 88% of the DF508 alleles are linked to haplotype B and suggests that high heterogeneity exists among the non-DF508 cystic fibrosis alleles occurring in different states. Our data can be used to compare linkage disequilibrium between Brazilians and other heterogeneous populations where the DF508 mutation frequency is low and where many different rare mutations account for the remaining recessive cystic fibrosis alleles.


Assuntos
Fibrose Cística/genética , Desequilíbrio de Ligação , Mutação/genética , Polimorfismo de Fragmento de Restrição , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Europa (Continente)/etnologia , Feminino , Heterogeneidade Genética , Heterozigoto , Humanos , Lactente , Masculino , População Branca/genética
15.
Hum Biol ; 69(1): 75-88, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9037896

RESUMO

The restriction fragment length polymorphism (RFLP) haplotypes of cystic fibrosis (CF) alleles vary between populations. To determine the distribution of two RFLPs (XV-2C and KM-19) that are tightly linked to the CF locus, we analyzed a white sample from five different states of Brazil. The haplotypes of 314 CF- and 237 non-CF-bearing chromosomes were uniformly distributed over the five states. The XV-2C allele and haplotype frequencies and the degree of linkage disequilibrium were determined. These were similar to values previously reported in southern European countries but different from results reported for northern and central Europe and North America. In contrast, although KM-19 allele frequencies differed between Brazilian states and European and North American countries, these frequencies were similar to values reported in black Americans. A significant proportion of Brazilian CF-bearing chromosomes had less common haplotypes, suggesting a heterogeneous distribution of CF gene mutations among Brazilians. Further studies are needed to identify the mutations affecting the Brazilian CF patients with various haplotypes.


Assuntos
Fibrose Cística/genética , Haplótipos/genética , Polimorfismo de Fragmento de Restrição , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Feminino , Frequência do Gene , Humanos , Lactente , Modelos Lineares , Desequilíbrio de Ligação , Masculino , Grupos Raciais/genética
16.
Bauru; Universidade do Sagrado Coraçäo; 1994. 103 p. ilus, tab.(Cadernos de Divulgaçäo Cultural, 44).
Monografia em Português | LILACS | ID: lil-180216

RESUMO

Objetivo deste estudo foi a análise do desempenho do deficiente auditivo adulto durante a prendizagem da leitura e escrita, com o auxílio de procedimentos de programaçao individualizada de ensino. A elaboraçao do Programa aqui utilizada, apoiou-se em estudos relativos às características: 1) da deficiência auditiva e da educaçao e alfabetizaçao do deficiente auditivo adulto; 2) do método de ensino conhecido como Programaçao Individualizada de Ensino associada ao uso dos sinais dactilológicos. O sujeito deste estudo foi um jovem de 19 anos de idade, portador de deficiência auditiva neuro-sensorial severa e anterior à aquisiçao de linguagem. Os dados mostram o desempenho deste sujeito em etapas do desenvolvimento do Programa. A análise dos resultados permitiu concluir um significativo enriquecimento do repertório léxico do sujeito e um sensível progresso no domínio das estruturas lingüísticas, em decorrência do emprego de uma orientaçao mista (oral/sinais dactilológicos) associada a uma programaçao para o ensino de leitura e escrita.


Assuntos
Humanos , Masculino , Adulto , Educação Inclusiva/métodos , Transtornos da Audição , Treinamento da Voz
17.
Am J Med Genet ; 46(6): 665-9, 1993 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8362909

RESUMO

A 3 bp deletion of codon 508 (phenylalanine) of the cystic fibrosis (CF) gene constitutes the mutation of most CF chromosomes. The frequency of this mutation (referred to as delta F508), varies considerably between populations, ranging from 26% of the CF mutations in Turkey to 88% in Denmark. To determine the frequency of the delta F508 mutation in Brazilian Caucasoid CF patients, we used direct polymerase chain reaction (PCR) amplification of DNA obtained from dried blood spots on Guthrie cards, followed by ethidium bromide staining of gels. Although the overall frequency of the delta F508 mutation was 47% of 380 CF chromosomes from Brazilian Caucasoids born in five different states, significant interstate differences were observed, ranging from a delta F508 frequency of 27% to 53%. While our method could be used to screen patients and their relatives for carrier testing and prenatal diagnosis, the efficacy of screening only for the delta F508 mutation would be low, and would vary from state to state. Screening for a panel of local mutations will be needed to increase the mutation detection rate and optimize genetic counseling.


Assuntos
Fibrose Cística/genética , Mutação , Sequência de Bases , Brasil/epidemiologia , Criança , Fibrose Cística/diagnóstico , Fibrose Cística/epidemiologia , DNA , Análise Mutacional de DNA , Feminino , Frequência do Gene , Humanos , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
18.
Arq. Inst. Penido Burnier ; 27: 10-3, 1985.
Artigo em Português | LILACS | ID: lil-77504

RESUMO

Os A.A. apresentam para registro, os dois primeiros casos da síndrome de insensibildiade congênita universal a dor, observados no Instituto Penido Burnier. Näo há mençäo de casos semelhantes na literatura oftalmológica nacional. Essa condiçäo mórbida näo tem sido considerada nem mesmo nos tratados clássicos da especialidade. A exceçäo é a Neuro-Oftalmologia de Walsh e Hoyt, 1969. Sobre um pano de fundo dominado pela insensibilidade a dor - condiçäo incompreensível e de significado inatingível pelas pessoas normais, que näo conseguem realizar intelectualemente um fato täo explicitamente de sensaçäo, ou melhormente, de falta de sensaçäo - desenrola-se uma infortunística traumatológica. O quadro ocular é dominado pelas lesöes corneanas , favorecidas pela insensibilidade, agravadas pelas alteraçöes do metabolismo do tecido de uma córnea anestésica e matizadas pela imprudência ingênua de crianças que näo aprenderam a inibir-se pelo freio repressivo da dor. Uma revisäo da matéria é feita. O quadro clínico é descrito em detalhes. O diagnóstico diferencial é considerado. O enfoque central da comunicaçäo é dado ao trabalho do oftalmologista em tentar evitar a cegueira total. Tratam-se de seqüências a longo prazo (16 anos). O quadro clínico de nossos pacientes justapöe-se, a perfeiçäo, aquelos referidos na literatura mundial


Assuntos
Pré-Escolar , Humanos , Masculino , Doenças da Córnea , Insensibilidade Congênita à Dor , Diagnóstico Diferencial , Seguimentos , Insensibilidade Congênita à Dor/diagnóstico
20.
Arch. domin. pediatr ; 18(2): 85-91, 1982.
Artigo em Espanhol | LILACS | ID: lil-8148

RESUMO

Se investiga la susceptibilidad a la rubeola en 200 mujeres de un nivel socioeconomico alto, encontrandose que el 44% no tenian titulaciones por IH. El diagnostico clinico no fue corroborado por IH en el 55,5% de los casos que supuestamente padecieron de rubeola.Solo el 10,5% de la muestra, fue vacunada anteriormente, pero el 38,2% carecia de titulaciones por IH


Assuntos
Adolescente , Adulto , Humanos , Feminino , Rubéola (Sarampo Alemão) , Imunidade , Fatores Socioeconômicos
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