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1.
Sci Total Environ ; 849: 157828, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35934022

RESUMO

External Thermal Insulation Composite Systems (ETICS) are multilayer solutions which provide an enhanced thermal performance to the building envelope. However, significant anomalies can be detected on ETICS facades, in some cases shortly after the application of these systems. This study intends to evaluate and compare the durability of six commercially available ETICS after two years of outdoor exposure at both urban and maritime conditions in Portugal. The systems were characterized by means of non-destructive testing (i.e., visual and microscopic assessment, water transport properties, thermal conductivity, surface roughness), thus allowing to evaluate the performance loss throughout natural aging. The bio-susceptibility and aesthetic properties (color and gloss) were also investigated. Results showed that the performance and durability of the complete system is significantly affected by the rendering system formulation. The lime-based specimens obtained the highest rate of mold development after one year of aging in a maritime environment, becoming considerably darker and with lower surface gloss. Fungal analysis of this darkish stained area indicated the presence of mold species of the genera Alternaria, Didymella, Cladosporium and Epicoccum, and yeasts of the genera Vishniacozyma and Cystobasidium. An increase of both capillary water absorption and water vapor permeability was also registered for the aged lime-based specimens. Acrylic-based systems obtained lower capillary water absorption after aging and greater dirt deposition on their surfaces, especially in urban conditions. These systems had also higher color variation and surface gloss decrease and slightly higher mold growth, when compared with those aged in a maritime environment. Finally, no mold growth was detected on the silicate-based specimens after two years of aging. However, these specimens obtained higher capillary water absorption and lower vapor permeability after aging, possibly leading to moisture accumulation within the system. Results contribute towards the development of ETICS with enhanced performance and durability.


Assuntos
Resinas Compostas , Vapor , Compostos de Cálcio , Teste de Materiais , Óxidos , Propriedades de Superfície
2.
Oecologia ; 195(4): 959-970, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33630170

RESUMO

Ants have efficient and well-studied social immunity mechanisms, which prevent the colony contamination. Little is known about how workers keep their outside territory clear of diseases. We investigated the interactions between Azteca chartifex ants, their associated bacteria and bacteria on the phyllosphere of Byrsonima sericea trees, comparing plants patrolled and not by the ants. The hypothesis is that bacteria associated with the worker's exoskeleton may outcompete the leaf bacteria. Culturable bacteria were isolated from ants, from the main and satellite nests, and from phyllosphere of B. sericea taken from trees that had A. chartifex nests and from trees without nests. The isolates were grouped by Gram guilds and identified at the genus level. There was a higher percentage of Gram-negative isolates in the ants and on the leaves patrolled by them. There was a higher growth rate of ant bacteria from the main nest compared to those found in ants from the satellite nests. The most representative genus among ant isolates was Enterobacter, also found on leaves patrolled by ants. Under favourable in vitro conditions, A. chartifex Gram-negative bacteria outcompete leaf bacteria by overgrowth, showing a greater competition capacity over the Gram-positive bacteria from leaves with no previous interaction with ants in the field. It was demonstrated that ants carry bacteria capable of outcompeting exogenous bacteria associated with their outside territory. The leaf microbiota of a patrolled tree could be shaped by the ant microbiota, suggesting that large ant colonies may have a key role in structuring canopy plant-microbe interactions.


Assuntos
Formigas , Animais , Bactérias , Bactérias Gram-Negativas , Humanos , Folhas de Planta , Árvores
3.
Arq. bras. med. vet. zootec ; 69(2): 483-490, mar.-abr. 2017. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-833965

RESUMO

Objetivou-se determinar as possíveis fontes de contaminação de Yersinia enterocolitica em diferentes pontos do processo de ordenha de vacas leiteiras em oito propriedades da região de Pelotas, RS, ao longo de um ano. Foram analisadas amostras de leite cru de conjunto logo após a ordenha, água de estábulo leiteiro, mão de ordenhador, balde de recolhimento do leite e insuflador de teteiras. As amostras de leite cru e água foram coletadas em frascos estéreis, e as amostras de mão, balde e teteiras com zaragatoas estéreis. As amostras de leite cru foram submetidas a um pré-enriquecimento em água peptonada, sendo posteriormente incubadas em caldo PSTA, adicionado de ampicilina. As amostras de água foram filtradas em membrana de éster de celulose e incubadas em caldo TSB. As amostras de leite após incubação em PSTA, as membranas utilizadas na filtragem da água incubadas em TSB, bem como o material de mãos, balde e teteiras coletadas nas zaragatoas, foram semeados em ágar MacConkey e incubados para a obtenção de colônias. Colônias características foram analisadas por meio de duplex PCR para confirmação da espécie. Os perfis moleculares dos isolados de Y. enterocolitica foram comparados utilizando-se a técnica de rep-PCR. Y. enterocolitica foi isolada de 9,37% das amostras de leite, 6,25% das amostras de água e 12,5% das amostras de mão. Não houve similaridade no perfil de bandas dos isolados encontrados, entretanto foi identificada a presença de cepas diferentes na mesma amostra, demonstrando uma variedade grande de cepas distribuídas no ambiente. A presença de Y. enterocolitica em leite cru no Brasil é preocupante, já que uma quantidade considerável do produto ainda é comercializada de forma clandestina, expondo o consumidor ao risco de infecção pela bactéria, ao consumi-lo sem tratamento térmico adequado.(AU)


This work was performed in order to determine the possible Yersinia enterocolitica contamination sources at different points of the dairy cows milking process in eight properties of Pelotas, RS, in a year. Raw milk samples were analyzed immediately after milking, as well as water from milking parlor, milkers' hands, milk collection bucket, and inflator liners. The samples of raw milk and water were collected in sterile bottles and hand samples, and sterile swabs were used for the buckets and liners. The raw milk samples were subjected to a pre-enrichment peptone water buffered and subsequently incubated in PSTA broth with added ampicillin. Water samples were filtered through cellulose ester membrane and incubated in TSB medium. The milk samples after incubation in PSTA, the membranes used in water filtration were incubated in TSB and the material of the hands material, bucket and liners collected in the swabs were plated on MacConkey agar to obtain colonies. Characteristics of colonies were analyzed by duplex PCR to confirm the species. The molecular profiles of Y. enterocolitica isolates were compared using rep-PCR. Y. enterocolitica was isolated from 9,37% of milk samples, 6,25% of water samples and 12,5% of hand samples. There weren't similarities in the band profile of the isolates found; however, the presence of different strains was found in the same sample, demonstrating a variety of strains distributed in the environment. The presence of Y. enterocolitica in raw milk in Brazil is dangerous, considering that the product is sold clandestinely, exposing consumers to the risk of infection by the bacterium, when consuming it without proper heat treatment.(AU)


Assuntos
Contaminação de Alimentos , Manipulação de Alimentos , Leite/microbiologia , Microbiologia da Água , Yersinia enterocolitica/isolamento & purificação , Bovinos , Gastroenterite , Reação em Cadeia da Polimerase/veterinária
4.
Indian J Med Microbiol ; 34(4): 506-508, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27934831

RESUMO

Photodynamic therapy (PDT) has been proved to be effective against fungi and it may be employed as a coadjutant to conventional antifungal agents, leading to a more effective microbial control minimising side effects. This work evaluates the combined effect of PDT and fluconazole against resistant Candida albicans, Candida glabrata and Candida krusei. The yeasts were submitted to methylene blue-PDT (MB-PDT) in sub-inhibitory concentrations. In the present work, MB-PDT combined with fluconazole was more efficient in the inhibition of the C. albicans and C. glabrata than each treatment alone, being possible to infer that the treatments are synergic.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/efeitos da radiação , Sinergismo Farmacológico , Fluconazol/farmacologia , Azul de Metileno/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Farmacorresistência Fúngica , Luz
5.
Benef Microbes ; 7(4): 549-57, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27133563

RESUMO

Indigenous microbiota plays a crucial role in the development of several intestinal diseases, including mucositis. Gastrointestinal mucositis is a major and serious side effect of cancer therapy, and there is no effective therapy for this clinical condition. However, some probiotics have been shown to attenuate such conditions. To evaluate the effects of Saccharomyces cerevisiae UFMG A-905 (Sc-905), a potential probiotic yeast, we investigated whether pre- or post-treatment with viable or inactivated Sc-905 could prevent weight loss and intestinal lesions, and maintain integrity of the mucosal barrier in a mucositis model induced by irinotecan in mice. Only post-treatment with viable Sc-905 was able to protect mice against the damage caused by chemotherapy, reducing the weight loss, increase of intestinal permeability and jejunal lesions (villous shortening). Besides, this treatment reduced oxidative stress, prevented the decrease of goblet cells and stimulated the replication of cells in the intestinal crypts of mice with experimental mucositis. In conclusion, Sc-905 protects animals against irinotecan-induced mucositis when administered as a post-treatment with viable cells, and this effect seems to be related with the reduction of oxidative stress and preservation of intestinal mucosa.


Assuntos
Mucosite/dietoterapia , Probióticos/uso terapêutico , Saccharomyces cerevisiae , Animais , Camptotecina/análogos & derivados , Modelos Animais de Doenças , Absorção Intestinal , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Irinotecano , Jejuno/patologia , Peroxidação de Lipídeos , Masculino , Camundongos , Mucosite/induzido quimicamente , Mucosite/patologia , Estresse Oxidativo , Redução de Peso
6.
Benef Microbes ; 6(6): 807-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26322540

RESUMO

In the present study, the protective potential of Saccharomyces cerevisiae strain UFMG A-905 was evaluated in a murine model of acute ulcerative colitis (UC). Six groups of Balb/c mice were used: not treated with yeast and not challenged with dextran sulphate sodium (DSS) (control); treated with S. cerevisiae UFMG A-905 (905); treated with the non-probiotic S. cerevisiae W303 (W303); challenged with DSS (DSS); treated with S. cerevisiae UFMG A-905 and challenged with DSS (905 + DSS); and treated with S. cerevisiae W303 and challenged with DSS (W303 + DSS). Seven days after induction of UC, mice were euthanised to remove colon for enzymatic, immunological, and histopathological analysis. In vivo intestinal permeability was also evaluated. An improvement of clinical manifestations of experimental UC was observed only in mice of the 905 + DSS group when compared to animals from DSS and W303 + DSS groups. This observation was confirmed by histological and morphometrical data and determination of myeloperoxidase and eosinophil peroxidase activities, intestinal permeability and some pro-inflammatory cytokines. S. cerevisiae UFMG A-905 showed to be a potential alternative treatment for UC when used in an experimental animal model of the disease.


Assuntos
Colo/patologia , Doenças Inflamatórias Intestinais/terapia , Probióticos/administração & dosagem , Saccharomyces cerevisiae/crescimento & desenvolvimento , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos Endogâmicos BALB C , Resultado do Tratamento
7.
J Perinatol ; 35(11): 954-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26378913

RESUMO

OBJECTIVE: The objective of this study was to assess the frequency of early deaths associated with birth asphyxia of very low birth weight infants between 2005 and 2010, in Brazil. STUDY DESIGN: This population study enrolled all live births with birth weight from 400 to 1499 g, gestational age ⩾ 22 weeks, without malformations that died up to 6 days after birth with perinatal asphyxia. Asphyxia was defined if intrauterine hypoxia, asphyxia at birth or meconium aspiration syndrome were written in any line of the death certificate. Active search was carried out in 27 Brazilian federative units. RESULT: For every 1000 live births of very low birth weight infants without congenital malformations, 40.25 and 32.38 died with birth asphyxia in the first week after birth, respectively, in 2005 and 2010 (P<0.001). The contribution of birth asphyxia to early neonatal death of these infants was approximately 10 to 12% all study years. CONCLUSION: Reduction of birth asphyxia in very low birth weight infants is essential to reducing neonatal mortality in Brazil.


Assuntos
Asfixia Neonatal/mortalidade , Causas de Morte , Recém-Nascido de muito Baixo Peso , Mortalidade Perinatal/tendências , Brasil/epidemiologia , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Incidência , Recém-Nascido , Masculino , Gravidez , Estudos Retrospectivos , Medição de Risco
8.
Am J Hum Biol ; 26(4): 559-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24668932

RESUMO

OBJECTIVES: Congenital adrenal hyperplasia (CAH) is a disease that occurs during fetal development and can lead to virilization in females or death in newborn males if not discovered early in life. Because of this there is a need to seek morphological markers in order to help diagnose the disease. In order to test the hypothesis that prenatal hormones can affect the sexual dimorphic pattern 2D:4D digit ratio in individual with CAH, the aim of this study was to compare the digit ratio in female and male patients with CAH and control subjects. METHODS: The 2D:4D ratios in both hands of 40 patients (31 females-46, XX, and 9 males-46, XY) were compared with the measures of control individuals without CAH (100 males and 100 females). RESULTS: Females with CAH showed 2D:4D ratios typical of male controls (0.950 and 0.947) in both hands (P < 0.001). In CAH males the left hand 2D:4D ratio (0.983) was statistically different from that of male controls (P < 0.05). CONCLUSIONS: These finding support the idea that sexual dimorphism in skeletal development in early fetal life is associated with differences between the exposure to androgens in males and females, and significant differences associated with adrenal hyperplasia. Although the effects of prenatal androgens on skeletal developmental are supported by numerous studies, further investigation is yet required to clarify the disease and establish the digit ratio as a biomarker for CAH.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Dedos/anatomia & histologia , Hiperplasia Suprarrenal Congênita/etiologia , Androgênios/metabolismo , Antropometria , Brasil , Criança , Feminino , Humanos , Masculino
9.
J Appl Microbiol ; 116(5): 1359-68, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24484457

RESUMO

AIMS: To compare the virulence pool and acute infection ability of Pseudomonas aeruginosa isolates from a hydropathic facility, used to treat respiratory conditions by inhalation of untreated natural mineral water, with clinical isolates from respiratory infections. METHODS AND RESULTS: Pseudomonas aeruginosa isolates from a hydropathic facility and from respiratory infections were typed by pulsed-field gel electrophoresis. Nonclonal representatives of each population were selected. 18 virulence-encoding genes were screened by polymerase chain reaction and statistically compared by multiple correspondence analysis. Homogeneous distribution of genes between populations but higher genetic association in aquatic isolates was observed, as well as distinct virulence pool according to location in the water system. Acute infection ability of selected isolates from each population, in Galleria mellonella model, showed lower LD50 of the majority of the hydropathic isolates and significant variations in LD50 of biofilm isolates from different equipments. CONCLUSIONS: Hydrotherapy Ps. aeruginosa isolates present similar virulence to isolates from respiratory infections. Hydrotherapy users may be exposed to different microbiological risks when using different treatment equipments. SIGNIFICANCE AND IMPACT OF THE STUDY: Twenty-one million people use hydropathic facilities in Europe, and the majority present risk factors to pneumonia. This study demonstrates the health risk associated with this practice. Revision of European regulations should be considered.


Assuntos
Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/patogenicidade , Infecções Respiratórias/microbiologia , Fatores de Virulência/genética , Animais , Biofilmes , Europa (Continente) , Instalações de Saúde , Humanos , Hidroterapia , Mariposas/microbiologia , Infecções por Pseudomonas/terapia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Infecções Respiratórias/terapia
10.
Arq. bras. med. vet. zootec ; 63(4): 914-921, ago. 2011. tab
Artigo em Português | LILACS | ID: lil-599611

RESUMO

O experimento foi realizado em dois anos para avaliar o potencial de produção de bovinos em pastagens de Brachiaria decumbens adubadas com nitrogênio (N). Foram determinadas as massas de forragem total (MFT) e de forragem verde (MFV), a composição morfológica e o valor nutritivo da forragem potencialmente consumível, bem como o desempenho animal e a taxa de lotação (TL) das pastagens. Os tratamentos consistiram de quatro doses de N - 75, 150, 225 e 300kg/ha.ano -, em delineamento de blocos ao acaso, com duas repetições. Nos dois anos, as MFT e MFV aumentaram linearmente em função da aplicação de N. A composição química da forragem potencialmente consumível foi pouco alterada pela aplicação de N. A adubação nitrogenada não influenciou o ganho de peso individual dos novilhos, mas aumentou a TL - de 3,6 para 5,3 e de 3,7 para 5,2UA/ha no primeiro e segundo ano, respectivamente - e a produção animal por área da pastagem - de 404,2 para 737,9 e de 619,7 para 1008,4kg/ha no primeiro e segundo anos, respectivamente.


The experiment which aimed to evaluate the potential of cattle production on nitrogen-fertilized Brachiaria decumbens pastures was carried out in two years. The total forage mass (TFM), green forage mass (GFM), morphological composition and nutritive value of the potentially consumed forage were determined, as well as the animal performance and the stocking rate (SR). The treatments encompassed four doses of N, being 75, 150, 225 and 300kg/ha.year. A randomized block design with two repetitions was used. The chemical composition of the potentially consumable forage was little altered by the N application. N-fertilization did not influence the weight gain of steers, but increased the SR from 3.6 to 5.3 in the first year and from 3.7 to 5.2 animal units per hectare in the second year, and the production by area of pasture from 404.2 to 737.9kg/ha in the first year and from 619.7 to 1008.4kg/ha in the second year. N-fertilization increases forage mass, stocking rate and animal production by area of pasture on B. decumbens cv. Basilisk pastures managed under continuous stocking with varying stocking rate.


Assuntos
Animais , Ração Animal , Bovinos/crescimento & desenvolvimento , Brachiaria/crescimento & desenvolvimento , Nitrogênio , Pastagens/métodos , Solos Argilosos , Compostagem , Indústria Agropecuária/métodos
11.
Braz. j. microbiol ; 39(4): 668-672, Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-504305

RESUMO

Denture stomatitis is an inflammatory condition that occurs in denture wearers and is frequently associated with Candida yeasts. Antifungal susceptibility profiles have been extensively evaluated for candidiasis patients or immunosupressed individuals, but not for healthy Candida carriers. In the present study, fluconazole, itraconazole, voriconazole, terbinafine and 5-flucytosin were tested against 109 oral Candida spp. isolates. All antifungal agents were effective against the samples tested except for terbinafine. This work might provide epidemiological information about Candida spp. drug susceptibility in oral healthy individuals.


A estomatite protética é uma condição inflamatória que ocorre em usuários de prótese total e está frequentemente associada a leveduras do gênero Candida, Os perfis de suscetibilidade a antifúngicos têm sido extensivamente estudados em pacientes com candidíase ou em indivíduos imunossuprimidos, mas não em portadores sadios de Candida. No presente estudo, fluconazol, itraconazol, voriconazol, terbinafina e 5-flucitosina foram testados contra 109 isolados orais de Candida spp. Todos os agentes antifúngicos mostraram-se eficazes contra as amostras avaliadas, exceto a Terbinafina. O presente trabalho pode fornecer dados epidemiológicos com relação à susceptibilidade a antifúngicos de Candida spp em indivíduos com saúde oral.


Assuntos
Humanos , Candidíase Bucal , Candida albicans/isolamento & purificação , Mucosa Bucal , Prostodontia , Estomatite , Leveduras , Epidemiologia , Métodos , Métodos
12.
Ann Hematol ; 87(2): 139-45, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17938926

RESUMO

Febrile neutropenia is associated with significant morbidity and mortality. Managing infectious in neutropenic patients remains a dynamic process, making necessary timely and efficient empirical antibiotic therapy. The implementation of critical pathways has been suggested as a strategy to improve clinical effectiveness. This study evaluated the compliance with an institutional critical pathway for the management of febrile neutropenia and the impact on clinical outcomes at Hospital de Clínicas de Porto Alegre, Brazil (HCPA). We performed a cohort study that prospectively included patients hospitalized from January 2004 to December 2005 and presented febrile neutropenia (190 episodes). Historical controls were selected from March 2001 to April 2003 (193 episodes) before the critical pathway was introduced. This study showed a low rate of full compliance (21.6%; 95% CI 15.7-27.5) with the critical pathway. In most cases, there was partial compliance (67.9%; 95% CI 61.3-74.5). Despite the moderate adherence observed, we recorded a decrease in in-hospital all-cause mortality in the sample studied after protocol implementation (from 24.4 to 14.4%; P = 0.017) and reduction in the length of use of cephalosporin and quinolones. In conclusion, implementation of a critical pathway seems to be an effective strategy to improve clinical outcomes in patients hospitalized with febrile neutropenia.


Assuntos
Antibacterianos/uso terapêutico , Procedimentos Clínicos , Febre/tratamento farmacológico , Fidelidade a Diretrizes , Neutropenia/tratamento farmacológico , Adulto , Brasil , Estudos de Casos e Controles , Feminino , Febre/mortalidade , Hospitais de Ensino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neutropenia/mortalidade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Resultado do Tratamento
13.
Braz J Microbiol ; 39(4): 668-72, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24031286

RESUMO

Denture stomatitis is an inflammatory condition that occurs in denture wearers and is frequently associated with Candida yeasts. Antifungal susceptibility profiles have been extensively evaluated for candidiasis patients or immunosupressed individuals, but not for healthy Candida carriers. In the present study, fluconazole, itraconazole, voriconazole, terbinafine and 5-flucytosin were tested against 109 oral Candida spp. isolates. All antifungal agents were effective against the samples tested except for terbinafine. This work might provide epidemiological information about Candida spp. drug susceptibility in oral healthy individuals.

14.
Eur J Clin Nutr ; 61(3): 382-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16988650

RESUMO

OBJECTIVE: To determine folates, vitamin B12 and total homocysteine levels among neonates from mothers of low or high socioeconomic status. DESIGN: We carried out a cross-sectional transversal study comprising 143 neonates from two maternity hospitals in the city of Salvador, Northeast of Brazil. Cord blood samples were obtained at the time of delivery from newborns from low (group 1, n=77) or high (group 2, n=66) socioeconomic status. The vitamin B12 and folates were analyzed by electrochemiluminescence immunoassay and by a competitive test using a natural folate-binding protein (FBP), respectively. Total homocyteine levels were measured by fluorescence polarization immunoassay. Maternal environmental risk factors for pregnancy complications were obtained from all mothers. RESULTS: Only 2% of women from group 1 received prenatal care/vitamin supplementation, whereas almost all mothers from group 2 (96%) were properly followed. Anemia and/or infections pre- or during pregnancy was more prevalent among mothers of babies from group 1. Folate levels among newborns from group 1 and 2 were 7.38+/-2.71 and 8.83+/-4.06 ng/ml, respectively. No difference in the vitamin B12 levels was determined between groups. In addition, tHcy serum levels were higher among newborns from group 1 compared to those from group 2 (8.54+/-4.06 vs 6.35+/-1.33 micromol/l, respectively; P=0.005). CONCLUSION: These results demonstrate that unprivileged young woman has limited accesses to prenatal care, present high-risk factors that hamper both maternal and newborn health. Maternal and newborn health status could be improved by simply reinforcing the use of folate-enriched diet. The work presented illustrates the challenges that developing countries have to face in order to provide preventive adequate health care to the population at large.


Assuntos
Ácido Fólico/sangue , Homocisteína/sangue , Recém-Nascido/sangue , Vitamina B 12/sangue , Complexo Vitamínico B/sangue , Adulto , Estudos Transversais , Suplementos Nutricionais , Feminino , Sangue Fetal/química , Humanos , Masculino , Estado Nutricional , Gravidez , Cuidado Pré-Natal , Classe Social , Fatores Socioeconômicos
15.
J Ind Microbiol Biotechnol ; 29(4): 170-6, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12355314

RESUMO

The commercial gelling agent, gellan, is an extracellular polysaccharide (EPS) produced by Sphingomonas paucimobilis ATCC 31461. In recent years, significant progress in understanding the relationship between gellan structure and properties and elucidation of the biosynthesis and engineering of this recent product of biotechnology has been made. This review focuses on recent advances in this field. Emphasis is given to identification and characterization of genes and enzymes involved, or predicted to be involved, in the gellan biosynthetic pathway, at the level of synthesis of sugar-activated precursors, of the repeat unit assembly and of gellan polymerization and export. Identification of several genes, biochemical characterization of the encoded enzymes and elucidation of crucial steps of the gellan pathway indicate that possibilities now exist for exerting control over gellan production at any of the three levels of its biosynthesis. However, a better knowledge of the poorly understood steps and of the bottlenecks and regulation of the pathway, the characterization of the composition, structure and functional properties of gellan-like polymers produced either by the industrial strain under different culture conditions or by mutants are still required for eventual success of the metabolic engineering of gellan production.


Assuntos
Genes Fúngicos/genética , Polissacarídeos Bacterianos/biossíntese , Sphingomonas/genética , Sphingomonas/metabolismo , Transporte Biológico , Biopolímeros/genética , Biopolímeros/metabolismo , Engenharia Genética , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo , Sphingomonas/enzimologia
16.
Nature ; 417(6887): 459-63, 2002 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-12024217

RESUMO

The genus Xanthomonas is a diverse and economically important group of bacterial phytopathogens, belonging to the gamma-subdivision of the Proteobacteria. Xanthomonas axonopodis pv. citri (Xac) causes citrus canker, which affects most commercial citrus cultivars, resulting in significant losses worldwide. Symptoms include canker lesions, leading to abscission of fruit and leaves and general tree decline. Xanthomonas campestris pv. campestris (Xcc) causes black rot, which affects crucifers such as Brassica and Arabidopsis. Symptoms include marginal leaf chlorosis and darkening of vascular tissue, accompanied by extensive wilting and necrosis. Xanthomonas campestris pv. campestris is grown commercially to produce the exopolysaccharide xanthan gum, which is used as a viscosifying and stabilizing agent in many industries. Here we report and compare the complete genome sequences of Xac and Xcc. Their distinct disease phenotypes and host ranges belie a high degree of similarity at the genomic level. More than 80% of genes are shared, and gene order is conserved along most of their respective chromosomes. We identified several groups of strain-specific genes, and on the basis of these groups we propose mechanisms that may explain the differing host specificities and pathogenic processes.


Assuntos
Genoma Bacteriano , Plantas/microbiologia , Xanthomonas/genética , Xanthomonas/fisiologia , Ordem dos Genes/genética , Interações Hospedeiro-Parasita , Dados de Sequência Molecular , Filogenia , Regulon/genética , Origem de Replicação/genética , Especificidade da Espécie , Virulência/genética , Xanthomonas/classificação , Xanthomonas/patogenicidade , Xanthomonas campestris/genética , Xanthomonas campestris/patogenicidade , Xanthomonas campestris/fisiologia
17.
Plant Mol Biol ; 47(6): 749-59, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11785936

RESUMO

Recently we described the novel nodulin gene VfENOD18, whose corresponding transcripts were restricted to the nitrogen-fixing zone III of broad bean root nodules. To characterize VfENOD18 on the protein level, polyclonal antibodies were generated using the purified recombinant VfENOD18 protein produced in Escherichia coli by employing the pMAL-c expression system. These antibodies recognized immunoreactive proteins isolated from indeterminate nodules of different leguminous plants, but also from non-symbiotic tissues of Glycine max and from tissues of Arabidopsis thaliana and Zea mays. Using immunogold labelling the nodulin VfENOD18 was localized to the cytoplasm of infected cells in the nitrogen-fixing zone of broad bean nodules. Due to the homology of the VfENOD18 sequence to that of the ATP-binding protein MJ0577 from the hyperthermophile Methanococcus jannaschii the recombinant VfENOD18 protein was tested for ATP-binding. Using the biotin photoaffinity ATP analogue 8N3ATP[gamma]biotin it could be demonstrated that VfENOD18 is an ATP-binding protein. PCR experiments revealed that the amino acid sequences of the putative C-terminal ATP-binding sites of the VfENOD 18 homologues from Lens culinaris, Vicia hirsuta, Vicia sativa and Vicia villosa were conserved. We propose that VfENOD18 is a member of a novel family of ATP-binding proteins in plants.


Assuntos
Trifosfato de Adenosina/metabolismo , Fabaceae/genética , Proteínas de Membrana , Proteínas de Plantas/genética , Raízes de Plantas/genética , Sequência de Aminoácidos , Anticorpos/imunologia , Arabidopsis/imunologia , Arabidopsis/metabolismo , Western Blotting , Fabaceae/citologia , Fabaceae/microbiologia , Mathanococcus/genética , Microscopia Imunoeletrônica , Dados de Sequência Molecular , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/ultraestrutura , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Rhizobium leguminosarum/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos , /metabolismo , Simbiose , Zea mays/imunologia , Zea mays/metabolismo
18.
Genet Couns ; 11(3): 249-59, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11043433

RESUMO

Two sibs with duplication of 4q31-->qter due to 3:1 meiotic disjunction and mild phenotype: Clinical and cytogenetic findings in two sibs with partial duplication of 4q31.3-->qter and 21q11.2-->pter are reported. These patients are rare cases of reoccurrence of those partial trisomies due to 3:1 segregation of a maternal balanced translocation. A review of the literature reporting cases of trisomy of the 4q31-->qter segment is also made; previously reported cases mostly in addition have deletions of other chromosomes resulting from adjacent segregation of balanced translocation. The findings of our study confirm the high risk for offspring with unbalanced rearrangements in women with reciprocal translocation involving acrocentric and short chromosome segments. The study also points out that duplication of 4q31-->qter may go along with only mild phenotypic findings if there is no significant additional aneuploidy of the other chromosome involved in the rearrangement.


Assuntos
Cromossomos Humanos Par 4/genética , Duplicação Gênica , Trissomia/genética , Cromossomos Humanos Par 21/genética , Feminino , Humanos , Recém-Nascido , Masculino , Meiose/genética , Linhagem , Fenótipo
19.
J Intellect Disabil Res ; 44 ( Pt 1): 91-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10711655

RESUMO

The present case study describes an adult male with clinical signs of mild Down's syndrome (DS), who performed well at school and reached university level. A karyotype was done on a lymphocyte culture and mosaic trisomy 21 was found in 3% of the 437 cells analysed. Eleven signs from Jackson's checklist were found in the clinical evaluation, which along with the analysis of the subject's dermatoglyphic traits, confirmed the DS diagnosis. Cognitive evaluation was done with several psychological tests and the results were within the average range. This rare phenotypic association shows that normal intellectual development may be possible in DS. This finding could be explained by the low trisomic cell frequency, which may have little effect on the critical tissues for intellectual development, and it might also reflect the wide phenotypic variation in mosaic trisomy 21. Other factors, such as strong family support, early and continued intervention programmes for both physical and speech therapy, and a thorough educational process, also provided opportunities for the development of the cognitive potential of the subject.


Assuntos
Síndrome de Down/genética , Síndrome de Down/psicologia , Inteligência , Mosaicismo/genética , Adulto , Criança , Escolaridade , Humanos , Cariotipagem , Masculino , Fenótipo , Desempenho Psicomotor
20.
Arch Microbiol ; 168(2): 92-101, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9238100

RESUMO

Fifty isolates belonging to the six validly described species of the genus Thermus (T. aquaticus, T. filiformis, T. thermophilus, T. scotoductus, T. brockianus, and T. oshimai) isolated from hot springs of different geographical areas were compared using macrorestriction analysis of genomic DNA and ribotyping. With the exception of presumed clones, the macrorestriction patterns of isolates obtained with EcoRI or NdeI were distinct. However, isolates belonging to the same species exhibited similar profiles particularly when they were isolated from the same hot spring. The estimated genomic size of strains of the Thermus spp. varied between approximately 1.8 and 2.5 Mbp. Ribotyping with BamHI and HindIII produced 30 and 35 distinct ribotypes, respectively. In spite of the variability of the hybridization patterns produced, the ribotypes obtained for isolates belonging to the same species also shared, in general, several fragments of identical size, and these fragments were similar when isolates originated from the same spring.


Assuntos
DNA Ribossômico/genética , Genoma Bacteriano , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Thermus/genética , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Campo Pulsado , Temperatura Alta , Especificidade da Espécie , Thermus/classificação , Microbiologia da Água
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