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1.
Braz J Biol ; 83: e277437, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422256

RESUMEN

The use of residues from coffee production to obtain biochar is a sustainable approach, which aims to minimize the environmental impact of these materials. In this study, the effect of adding coffee straw biochar on the physiological quality of lettuce and sorghum seeds was investigated. Thus, the objective of this work was to study the effect of adding different concentrations of coffee biochar in the substrate composition on the physiological quality of lettuce (Lactuca sativa) and sorghum (Sorghum bicolor) seeds. The experimental design used was completely randomized, with five concentrations of biochar (0; 7.5; 15; 30 and 60%), conducted with four replications of 25 seeds. The use of biochar in the concentrations studied does not provide an increase in the average germination percentage and vigor of lettuce and sorghum seeds. The increase in the concentration of biochar caused less seed vigor, suggesting a toxic effect. For seed germination, there was no significant difference between lettuce and sorghum species, regardless of treatment. For the germination speed index, sorghum seeds have higher means, except for the treatment with the addition of 15% coffee straw biochar. Lettuce seeds have higher shoot length averages, except for treatment with 100% commercial substrate. The sorghum seeds have higher mean root length and dry mass than lettuce, regardless of the treatment.


Asunto(s)
Carbón Orgánico , Germinación , Sorghum , Café , Grano Comestible , Lactuca , Semillas/fisiología
2.
J Dairy Sci ; 103(3): 2098-2110, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31980224

RESUMEN

Staphylococcus aureus is one of the main pathogens found in cheeses produced with raw milk, including Minas artisanal cheese from Brazil. However, information about S. aureus isolated from artisanal cheeses and its sources of production in small-scale dairies is very limited. We aimed to characterize the virulence factors of S. aureus isolated from raw milk, endogenous starter culture, Minas artisanal cheese, and cheese handlers from the region of Campo das Vertentes, Minas Gerais, Brazil. We identified the staphylococcal isolates by MALDI-TOF mass spectrometry. We evaluated biofilm production on Congo red agar and polystyrene plates. We used PCR to detect icaA, icaB, icaC, sea, seb, sec, sed, see, tsst-1, agr, and mecA. We evaluated the expression of staphylococcal toxin genes in PCR-positive staphylococcal isolates using quantitative reverse-transcription PCR, and we evaluated the production of these toxins and their hemolytic activity in vitro. We also evaluated the antimicrobial resistance profile of the staphylococcal isolates. For statistical analysis, we used cluster analysis, χ2 tests, and correspondence tests. We analyzed 76 staphylococcal isolates. According to PCR, 18.42, 18.42, 2.63, and 77.63% were positive for sea, tsst-1, sec, and agr, respectively. We found low expression of staphylococcal toxin genes according to quantitative reverse-transcription PCR, and only 2 staphylococcal isolates produced toxic shock syndrome toxins. A total of 43 staphylococcal isolates (56.58%) had hemolytic activity; 53 were biofilm-forming on Congo red agar (69.73%), and 62 on polystyrene plates (81.58%). None of the staphylococcal isolates expressed the mecA gene, and none presented a multi-drug resistance pattern. The highest resistance was observed for penicillin G (67.11%) in 51 isolates and for tetracycline (27.63%) in 21 isolates. The staphylococcal isolates we evaluated had toxigenic potential, with a higher prevalence of sea and tsst-1. Biofilm production was the main virulence factor of the studied bacteria. Six clusters were formed whose distribution frequencies differed for hemolytic activity, biofilm formation (qualitative and quantitative analyses), and resistance to penicillin, tetracycline, and erythromycin. These findings emphasize the need for effective measures to prevent staphylococcal food poisoning by limiting S. aureus growth and enterotoxin formation throughout the food production chain and the final product.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Queso/microbiología , Farmacorresistencia Bacteriana , Choque Séptico/microbiología , Intoxicación Alimentaria Estafilocócica/microbiología , Staphylococcus aureus/genética , Factores de Virulencia , Animales , Antibacterianos/farmacología , Toxinas Bacterianas/genética , Brasil , Enterotoxinas/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/patogenicidad , Superantígenos/genética
3.
Microb Pathog ; 100: 312-318, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27725281

RESUMEN

Coagulase-negative staphylococci (CNS) represent one of the most prevalent microorganisms in nosocomial infections worldwide, nevertheless little is known about their pathogenicity features. Thus, our aim was to characterize virulence aspects of CNS isolated from patients with bloodstream infections assisted in hospitals of Belo Horizonte, MG, Brazil. Strains were identified using bioMérieuxVitek® and for biofilm production evaluation, Congo Red Agar (CRA) and polystyrene plates were used. PCR was applied to detect icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr. For statistical analyses were used hierarchical cluster, chi-square test and correspondence. 59 strains were analyzed, being S. haemolyticus the most prevalent. On CRA, 96.5% were biofilm producer, whereas on polystyrene plate, 100% showed adhesion at different times evaluated. Regarding genotypic analyses, 15.2%, 38.9%, 8.4%, 49.1%, 76.2%, 23.7%, 1.6%, 30.5% and 38.9% were positive for icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr, respectively. Six clusters were formed and frequency distributions of agr, atlE, icaA, icaB, sea, sec, tsst-1 differed (P < 0.001). In conclusion, all strains were biofilm producer, with high prevalence of atlE, and had potential of toxin production, with high prevalence of sea. According to the group-analyses, icaB showed relationship with the strong adherence in samples.


Asunto(s)
Toxinas Bacterianas/análisis , Biopelículas/crecimiento & desarrollo , Sepsis/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus/fisiología , Adhesión Bacteriana , Toxinas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Brasil , Análisis por Conglomerados , Infección Hospitalaria/microbiología , Genotipo , Hospitales , Humanos , Reacción en Cadena de la Polimerasa , Staphylococcus/clasificación , Staphylococcus/aislamiento & purificación , Staphylococcus/metabolismo , Factores de Virulencia/análisis , Factores de Virulencia/genética
4.
Neurochem Res ; 41(1-2): 116-29, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26518676

RESUMEN

We aimed to investigate the potential beneficial effects of the Brazilian Pampa biome honey in a Drosophila-based hypoxia model. Adult flies were reared in standard medium in the presence or absence of honey (at a final concentration of 10 % in medium). Then, control flies (4 % sucrose in medium) and honey-treated flies were submitted to hypoxia. Subsequently, flies were analyzed for mortality, neurolocomotor behavior (negative geotaxis), mitochondrial/oxidative stress parameters and expression of hypoxia/stress related genes by RT-qPCR. The HPLC analysis revealed the presence of phenolics and flavonoids in the studied honey. Caffeic acid was the major compound followed by p-coumaric acid and kaempferol. The presence of such compounds was correlated with a substantial antioxidant activity in vitro. Flies subjected to hypoxia presented marked mortality, locomotor deficits and changes in oxidative stress and mitochondrial activity parameters. Honey treatment was able to completely block mortality and locomotor phenotypes. In addition, honey was able to reverse ROS production and hypoxia-induced changes in mitochondrial complex I and II activity. Hypoxia also induced an up-regulation in mRNA expression of Sima (HIF-1), NFκß, NRF2, HOX, AKT-1, InR, dILP2, dILP5 and HSP27. Honey treatment was not able to modulate changes in the tested genes, indicating that its protective effects involve additional mechanisms other than transcriptional activity of hypoxia-driven adaptive responses in flies. Our results demonstrated, for the first time, the beneficial effects of honey against the deleterious effects of hypoxia/reperfusion processes in a complex organism.


Asunto(s)
Miel , Locomoción , Estrés Oxidativo , Daño por Reperfusión/prevención & control , Animales , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Drosophila melanogaster/genética , Flavonoides/análisis , Expresión Génica , Miel/análisis , Fenoles/análisis , Espectrofotometría Ultravioleta
5.
World J Microbiol Biotechnol ; 30(10): 2689-700, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24980943

RESUMEN

Biofilm formation on reverse osmosis (RO) systems represents a drawback in the application of this technology by different industries, including oil refineries. In RO systems the feed water maybe a source of microbial contamination and thus contributes for the formation of biofilm and consequent biofouling. In this study the planktonic culturable bacterial community was characterized from a feed water of a RO system and their capacities were evaluated to form biofilm in vitro. Bacterial motility and biofilm control were also analysed using phages. As results, diverse Protobacteria, Actinobacteria and Bacteroidetes were identified. Alphaproteobacteria was the predominant group and Brevundimonas, Pseudomonas and Mycobacterium the most abundant genera. Among the 30 isolates, 11 showed at least one type of motility and 11 were classified as good biofilm formers. Additionally, the influence of non-specific bacteriophage in the bacterial biofilms formed in vitro was investigated by action of phages enzymes or phage infection. The vB_AspP-UFV1 (Podoviridae) interfered in biofilm formation of most tested bacteria and may represent a good alternative in biofilm control. These findings provide important information about the bacterial community from the feed water of a RO system that may be used for the development of strategies for biofilm prevention and control in such systems.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacteriófagos/fisiología , Biopelículas/crecimiento & desarrollo , Podoviridae/fisiología , Microbiología del Agua , Bacterias/crecimiento & desarrollo , Bacteriófagos/aislamiento & purificación , Biodiversidad , Agentes de Control Biológico , Ósmosis , Petróleo/microbiología , Filogenia , Podoviridae/aislamiento & purificación , Técnica del ADN Polimorfo Amplificado Aleatorio , Análisis de Secuencia de ADN , Purificación del Agua
6.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);65(5): 1537-1544, out. 2013. graf, tab
Artículo en Inglés | LILACS | ID: lil-689774

RESUMEN

The production of Toxic Shock Syndrome Toxin-1 (TSST-1), enterotoxins and bacteriocin-like substances was evaluated in 95 strains of Staphylococcus aureus recovered from raw bovine milk (n=31) and from food samples involved in staphylococcal food poisoning (n=64). Enterotoxigenicity tests with the membrane over agar associated to optimal sensibility plate assays were performed and showed that 96.77% of strains recovered from milk and 95.31% from food samples produced enterotoxins A, B, C, D or TSST-1. Reference strains S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella Typhimurium, Escherichia coli, Enterococcus faecalis and Bacteroides fragilis were used as indicator bacteria in the antagonistic assays, the first five being sensitive to antagonistic substances. Brain heart infusion agar, in pH values ranging from 5.0 to 7.0 in aerobic atmosphere showed to be the optimum condition for antagonistic activity as evaluated with the best producer strains against the most sensitive indicator bacterium, L. monocytogenes. Sensitivity to enzymes confirmed the proteinaceous nature of these substances. Neither bacteriophage activity nor fatty acids were detected and the antagonistic activity was not due to residual chloroform. Results did not establish a positive correlation between the bacteriocinogenic profile and toxigenicity in the tested S. aureus strains.


Avaliou-se a produção de toxina-1 da síndrome do choque tóxico (TSST-1), enterotoxinas e substâncias antagonistas tipo bacteriocina em 95 amostras de Staphylococcus aureus recuperadas de leite bovino in natura (n=31) e de alimentos envolvidos em surto de intoxicação (n=64). Testes de enterotoxigenicidade pelo método da membrana sobre ágar, associado à técnica da sensibilidade ótima em placa, revelaram que 96,77% das amostras do leite e 95,31% daquelas dos alimentos produziram enterotoxinas estafilocócicas tipos A, B, C, D ou TSST-1. Nos ensaios de antagonismo, foram utilizadas como reveladoras amostras de referência de S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella typhimurium, Escherichia coli, Enterococcus faecalis e Bacteroides fragilis, sendo as cinco primeiras sensíveis às substâncias produzidas. As condições ótimas para a atividade antagonista, avaliadas com as melhores produtoras contra a indicadora mais sensível, L. monocytogenes, foram observadas em aerobiose, em ágar infuso de cérebro-coração, nos valores de pH entre 5,0 e 7,0. A sensibilidade a enzimas confirmou a natureza proteica destas substâncias. Não foram detectadas atividades de bacteriófagos nem de ácidos graxos, e a atividade antagonista não foi devido ao clorofórmio residual. Os resultados não mostraram correlação entre o perfil bacteriocinogênico e a toxigenicidade nas amostras de Staphylococcus testadas.


Asunto(s)
Animales , Bovinos , Bacteriocinas , Bacteriocinas/análisis , Choque Séptico/veterinaria , Enfermedades Transmitidas por los Alimentos/veterinaria , Enterotoxinas/administración & dosificación , Enterotoxinas/análisis , Listeria monocytogenes , Mastitis Bovina , Alimentos , Staphylococcus aureus
7.
Arq. bras. med. vet. zootec ; 65(5): 1537-1544, Oct. 2013. graf, tab
Artículo en Inglés | VETINDEX | ID: vti-10045

RESUMEN

The production of Toxic Shock Syndrome Toxin-1 (TSST-1), enterotoxins and bacteriocin-like substances was evaluated in 95 strains of Staphylococcus aureus recovered from raw bovine milk (n=31) and from food samples involved in staphylococcal food poisoning (n=64). Enterotoxigenicity tests with the membrane over agar associated to optimal sensibility plate assays were performed and showed that 96.77% of strains recovered from milk and 95.31% from food samples produced enterotoxins A, B, C, D or TSST-1. Reference strains S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella Typhimurium, Escherichia coli, Enterococcus faecalis and Bacteroides fragilis were used as indicator bacteria in the antagonistic assays, the first five being sensitive to antagonistic substances. Brain heart infusion agar, in pH values ranging from 5.0 to 7.0 in aerobic atmosphere showed to be the optimum condition for antagonistic activity as evaluated with the best producer strains against the most sensitive indicator bacterium, L. monocytogenes. Sensitivity to enzymes confirmed the proteinaceous nature of these substances. Neither bacteriophage activity nor fatty acids were detected and the antagonistic activity was not due to residual chloroform. Results did not establish a positive correlation between the bacteriocinogenic profile and toxigenicity in the tested S. aureus strains.(AU)


Avaliou-se a produção de toxina-1 da síndrome do choque tóxico (TSST-1), enterotoxinas e substâncias antagonistas tipo bacteriocina em 95 amostras de Staphylococcus aureus recuperadas de leite bovino in natura (n=31) e de alimentos envolvidos em surto de intoxicação (n=64). Testes de enterotoxigenicidade pelo método da membrana sobre ágar, associado à técnica da sensibilidade ótima em placa, revelaram que 96,77% das amostras do leite e 95,31% daquelas dos alimentos produziram enterotoxinas estafilocócicas tipos A, B, C, D ou TSST-1. Nos ensaios de antagonismo, foram utilizadas como reveladoras amostras de referência de S. epidermidis, Bacillus cereus, Listeria monocytogenes, Lactobacillus casei, Pseudomonas aeruginosa, S. aureus, Salmonella typhimurium, Escherichia coli, Enterococcus faecalis e Bacteroides fragilis, sendo as cinco primeiras sensíveis às substâncias produzidas. As condições ótimas para a atividade antagonista, avaliadas com as melhores produtoras contra a indicadora mais sensível, L. monocytogenes, foram observadas em aerobiose, em ágar infuso de cérebro-coração, nos valores de pH entre 5,0 e 7,0. A sensibilidade a enzimas confirmou a natureza proteica destas substâncias. Não foram detectadas atividades de bacteriófagos nem de ácidos graxos, e a atividade antagonista não foi devido ao clorofórmio residual. Os resultados não mostraram correlação entre o perfil bacteriocinogênico e a toxigenicidade nas amostras de Staphylococcus testadas.(AU)


Asunto(s)
Animales , Bovinos , Choque Séptico/veterinaria , Enterotoxinas/administración & dosificación , Enterotoxinas/análisis , Bacteriocinas/análisis , Mastitis Bovina , Enfermedades Transmitidas por los Alimentos/veterinaria , Bacteriocinas , Listeria monocytogenes , Staphylococcus aureus , Alimentos
8.
J Anim Sci ; 91(8): 3930-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23893999

RESUMEN

Bovine mastitis is the primary disease of dairy cattle worldwide and it causes large economic losses. Among several microorganisms that are the causative agents of this disease, Staphylococcus aureus is the most prevalent. Although antibiotic therapy is still the most widely used procedure for the treatment of bovine mastitis, alternative means of treatment are necessary due to the presence of antibiotic residues in milk, which is a growing concern because of its interference with the production of milk derivatives and the selection of resistant bacterial strains. The use of bacteriophages as a tool for the control of pathogens is an alternative treatment to antibiotic therapy. In this work, to obtain phages with the potential for use in phage therapy as a treatment for mastitis, we isolated and identified the bacteria from the milk of mastitis-positive cows. A total of 19% of the animals from small and medium farms of the Zona da Mata Mineira, Brazil, was positive for bovine mastitis, and bacteria of the genus Staphylococcus were the most prevalent pathogens. The majority of the S. aureus isolates tested was resistant to penicillin and ampicillin. In parallel, we isolated 10 bacteriophages able to infect some of these S. aureus isolates. We determined that these phages contained DNA genomes of approximately 175 kb in length, and the protein profiles indicated the presence of 4 major proteins. Electron microscopy revealed that the phages are caudate and belong to the Myoviridae family. The isolates exhibited interesting features for their use in phage therapy such as a high lytic potential, a wide range of hosts, and thermostability, all of which favor their use in the field.


Asunto(s)
Mastitis Bovina/microbiología , Infecciones Estafilocócicas/veterinaria , Fagos de Staphylococcus/fisiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/virología , Animales , Bovinos , Femenino , Especificidad del Huésped , Infecciones Estafilocócicas/microbiología
9.
Arch Virol ; 157(12): 2265-72, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22865166

RESUMEN

In this study, we isolated and characterized a lytic Lactococcus lactis bacteriophage from the sera of a failed fermentation. The phage was isolated and cultured in L. lactis subsp. cremoris in M17 medium. The isolated bacteriophage was characterized by multiplex PCR, pulsed-field electrophoresis, DNA restriction digestion, analysis of the N-terminal sequence of the phage major structural protein, transmission electron microscopy and sequencing and analysis of a conserved fragment of its genome. Analysis of the viral genome indicates that its genome is composed of a DNA strand of approximately 48 kb in length, and PCR and microscopy confirmed that IL-P1 belongs to the group of 936-type phages in the family Siphoviridae, which is the most abundant type of lactococcal virus in dairy products worldwide. To our knowledge, this is the first report of a virus within this family that has a presumptive genome larger than 40 kb.


Asunto(s)
Queso/microbiología , Lactococcus lactis/virología , Siphoviridae/clasificación , Secuencia de Aminoácidos , Animales , ADN Viral/química , ADN Viral/genética , Electroforesis en Gel de Campo Pulsado , Genoma Viral/genética , Anotación de Secuencia Molecular , Filogenia , Mutación Puntual , Reacción en Cadena de la Polimerasa , Mapeo Restrictivo , Alineación de Secuencia , Siphoviridae/genética , Siphoviridae/aislamiento & purificación , Siphoviridae/ultraestructura , Proteínas Virales/química , Proteínas Virales/genética
10.
Technol Cancer Res Treat ; 10(6): 585-90, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22066598

RESUMEN

The purpose of this study was to evaluate rectum motion during 3-Dimensional conformal radiation therapy (3D-CRT) in prostate cancer patients, to derive a planning volume at risk (PRV) and to correlate the PRV dose-volume histograms (DVH) with treatment complications.This study was conducted in two phases. Initially, the PRV was defined prospectively in 50 consecutive prostate cancer patients (Group 1) who received a radical course of 3-D CRT. Then, the obtained PRV was used in the radiotherapy planning of these same 50 patients plus another 59 prostate cancer patients (Group 2) previously treated between 2004 and 2008. All these patients' data, including the rectum and PRV DVHs, were correlated to acute and late complications, according to the Common Toxicity Criteria (CTC) v4.0.The largest displacement occurred in the anterior axis. Long-term gastrointestinal (GI) complications grade ≥ 2 were seen in 9.2% of the cases. Factors that influenced acute GI reactions were: doses at 25% (p 5 0.011) and 40% (p 5 0.005) of the rectum volume and at 40% of the PRV (p 5 0.012). The dose at 25% of the rectum volume (p 5 0.033) and acute complications ≥ grade 2 (p 5 0.018) were prognostic factors for long-term complications. The PRV DVH did not correlate with late toxicity. The rectum showed a significant inter-fraction motion during 3D-CRT for prostate cancer. PRV dose correlated with acute gastrointestinal complications and may be a useful tool to predict and reduce their occurrence.


Asunto(s)
Enfermedades Gastrointestinales/etiología , Imagenología Tridimensional , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Traumatismos por Radiación/etiología , Planificación de la Radioterapia Asistida por Computador , Radioterapia Conformacional/efectos adversos , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias de la Próstata/complicaciones
11.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);61(1): 170-173, fev. 2009.
Artículo en Inglés | LILACS | ID: lil-513039

RESUMEN

Acute toxicity test (LD-50) using toxic shock syndrome toxin (TSST-1) was tested in BALB/c, C57BL/6 and Swiss mice. Animals (n = 10) were intraperitoneally injected with TSST-1 (0.01-10.0µg/mouse) followed 4h later by potentiating dose of lipopolysaccharide (75.0µg of LPS - E. coli O111:B4) and cumulative mortality was recorded over 72h. Control animals received either TSST-1 or LPS alone. The data were submitted to qui-Square test and acute toxicity test was calculated by probit analysis (confidence limits expressed as µg toxin/kg). BALB/c mice was the most sensitive (20.0µg/kg, 95 percent confidence limits: 9.0-92.0) followed by C57BL/6 (38.5µg/kg, 95 percent confidence limits: 9.11- 401.6). Data from Swiss mice was not conclusive, indicating only low sensitivity. Selection of the animal model and standardization of the experiment are fundamental for the development of serum neutralization tests used for final quality control of vaccine production.


A toxicidade aguda (DL-50) da toxina da síndrome do choque tóxico (TSST-1) foi testada em linhagens de camundongos BALB/c, C57BL/6 e Suíça. Os animais (n=10) inoculados intraperitoneal com doses crescentes de toxina (0,01 - 10,0µg/animal) receberam 4h após 75µg de LPS (E. coli O111: B4). A toxicidade aguda (DL50) foi observada por um período de 72h e os dados submetidos ao teste de qui- quadrado. Os resultados e os limites de confiança foram expressos em µg de toxina/kg. A linhagem BALB/c apresentou maior sensibilidade (20µg/kg - limite de confiança a 95 por cento entre 9,0- 92,0), seguida da C57BL/6 (38,5µg/kg - limite de confiança a 95 por cento entre 9,11 - 401,6). A amplitude dos limites de confiança deve-se à natureza da toxina, ao mecanismo de ação, a via de inoculação e ao animal utilizado. A seleção do modelo animal e a padronização do experimento são fundamentais para o desenvolvimento de testes de soro neutralização para fins de controle de qualidade do processo de produção de vacinas.


Asunto(s)
Animales , Experimentación Animal , Choque Séptico/inducido químicamente , Ratones , Modelos Animales , Pruebas de Toxicidad Aguda/análisis
12.
Arq. bras. med. vet. zootec ; 61(1): 170-173, Feb. 2009.
Artículo en Inglés | VETINDEX | ID: vti-6204

RESUMEN

Acute toxicity test (LD-50) using toxic shock syndrome toxin (TSST-1) was tested in BALB/c, C57BL/6 and Swiss mice. Animals (n = 10) were intraperitoneally injected with TSST-1 (0.01-10.0µg/mouse) followed 4h later by potentiating dose of lipopolysaccharide (75.0µg of LPS - E. coli O111:B4) and cumulative mortality was recorded over 72h. Control animals received either TSST-1 or LPS alone. The data were submitted to qui-Square test and acute toxicity test was calculated by probit analysis (confidence limits expressed as µg toxin/kg). BALB/c mice was the most sensitive (20.0µg/kg, 95 percent confidence limits: 9.0-92.0) followed by C57BL/6 (38.5µg/kg, 95 percent confidence limits: 9.11- 401.6). Data from Swiss mice was not conclusive, indicating only low sensitivity. Selection of the animal model and standardization of the experiment are fundamental for the development of serum neutralization tests used for final quality control of vaccine production.(AU)


A toxicidade aguda (DL-50) da toxina da síndrome do choque tóxico (TSST-1) foi testada em linhagens de camundongos BALB/c, C57BL/6 e Suíça. Os animais (n=10) inoculados intraperitoneal com doses crescentes de toxina (0,01 - 10,0µg/animal) receberam 4h após 75µg de LPS (E. coli O111: B4). A toxicidade aguda (DL50) foi observada por um período de 72h e os dados submetidos ao teste de qui- quadrado. Os resultados e os limites de confiança foram expressos em µg de toxina/kg. A linhagem BALB/c apresentou maior sensibilidade (20µg/kg - limite de confiança a 95 por cento entre 9,0- 92,0), seguida da C57BL/6 (38,5µg/kg - limite de confiança a 95 por cento entre 9,11 - 401,6). A amplitude dos limites de confiança deve-se à natureza da toxina, ao mecanismo de ação, a via de inoculação e ao animal utilizado. A seleção do modelo animal e a padronização do experimento são fundamentais para o desenvolvimento de testes de soro neutralização para fins de controle de qualidade do processo de produção de vacinas.(AU)


Asunto(s)
Animales , Modelos Animales , Experimentación Animal , Choque Séptico/inducido químicamente , Pruebas de Toxicidad Aguda/análisis , Ratones
13.
Fetal Diagn Ther ; 23(1): 23-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17934294

RESUMEN

OBJECTIVE: To describe the main perinatal and 1-year outcomes in babies with a prenatal ultrasonographic diagnosis of severe hydrocephalus according to the presence or absence of a neural tube defect (NTD) in a country where abortion is illegal. METHOD: The study population consisted of cases referred to and delivered at Hospital de Clínicas de Porto Alegre, diagnosed between January 1993 and December 2001. The diagnosis of severe hydrocephalus was based on a lateral ventricular atrium diameter > or =15 mm in at least one hemisphere. RESULTS: Sixty cases were ascertained: 28 with NTD (group 1) and 32 without NTD (group 2). The groups were similar in terms of maternal and child variables at birth and hospitalization days during the 1st year of life. The mortality (including intrauterine deaths and deaths of babies with malformations incompatible with life that characterize a very poor prognosis) until 1 year of age was 36% in group 1 and 59% in group 2 (p = 0.077). The rate of cardiac malformations was higher in the group without NTD (p = 0.015). The length of hospital stay after birth (1st admission) was significantly higher in the group with NTD (p = 0.007). CONCLUSIONS: The morbidity was higher in the group with NTD, possibly due to the higher number of surgical interventions in the central nervous system. However, the mortality was higher in the group without NTD, possibly due to the presence of other associated malformations, especially congenital heart disease. Further studies should focus on neurological function and quality of life of the children and their families at the end of the 1st year and after 2 or 6 years of age.


Asunto(s)
Enfermedades Fetales/diagnóstico , Hidrocefalia/complicaciones , Hidrocefalia/diagnóstico , Defectos del Tubo Neural/complicaciones , Defectos del Tubo Neural/diagnóstico , Femenino , Enfermedades Fetales/epidemiología , Estudios de Seguimiento , Humanos , Hidrocefalia/epidemiología , Lactante , Recién Nacido , Defectos del Tubo Neural/epidemiología , Embarazo , Estudios Retrospectivos
14.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);59(1): 203-209, fev. 2007. tab
Artículo en Portugués | LILACS | ID: lil-456437

RESUMEN

Foram utilizados 12 cordeiros machos, inteiros, com peso médio de 31,6kg. Os cordeiros foram alimentados com dietas à base de milho e farelo de soja, suplementadas com diferentes fontes de cálcio: calcário calcítico (CC), feno de alfafa (FA), polpa cítrica (PC) e farinha de conchas de ostras (FCO). Os animais receberam injeção de 7,4 MBq do radiofósforo (32P) e após sete dias foram abatidos para posteriores análises. Utilizou-se o delineamento em blocos ao acaso, com quatro tratamentos e três repetições. A taxa de retenção de 32P, as atividades específicas relativas e padronizadas, e a quantidade de P inorgânico nos tecidos foram iguais para todos os tratamentos (P>0,05). A comparação entre os tecidos mostrou que a concentração de P inorgânico e a taxa de retenção de 32P (P<0,01) foram mais altas nos ossos em relação aos tecidos moles (P<0,01). A retenção de 32P apresentou a seguinte ordem decrescente: rins, fígado, coração, músculos e ossos (P<0,01). A reabsorção óssea de P foi maior que a deposição de P, levando ao balanço negativo do elemento para a maioria dos animais. Concluiu-se que as diferentes fontes de cálcio não interferiram na cinética do P e que a quantidade de P ingerida não atendeu às exigências de P dos animais.


Sixteen growing rams, averaging 31.6kg were studied. They were fed diets based on corn and soya meal, supplemented with different sources of calcium: limestone (CC), alfalfa hay (FA), citrus pulp (PC) and oyster shell meal (OSM). The animals received an injection of 7.4 MBq of radioactive P (32P) and after 7 days they were slaughtered for further analyses. Experimental measurements were analyzed as a completely randomized design with four treatments and three repetitions. The rate of 32P retention, the relative specific activity, the standardized specific activity and the inorganic P in tissue were similar for all treatments (P>0.05). The comparison between tissues showed that the concentration of inorganic P and rate of 32P retention was greater in bone (P<0.01) than in soft tissue. The 32P retention presented the following decreasing order: kidney, liver, heart, muscle and bone (P<0.01). P resorption in bone was higher than P accreted in bone, leading to a negative balance of P in bone for the majority of animals. The means for P accreted in bone were 1.56, 3.29, 2.74 and 2.06g/animal and the means for P resorption in bone were 2.82, 4.51, 4.09 and 3.05g/animal for limestone (CC), alfalfa hay (FA), citrus pulp (PC) and oyster shell meal (OSM), respectively. P resorption values were higher than P accretion in bone leading to a negative balance of P for the majority of animals. It was concluded that the different sources of calcium did not interfere in the kinetics of phosphorus and the amount of P absorbed did not attend P demands of the animals.


Asunto(s)
Resorción Ósea , Calcio de la Dieta/análisis , Calcio de la Dieta/metabolismo , Fósforo/administración & dosificación , Huesos/fisiología , Ovinos , Suplementos Dietéticos/análisis
15.
Arq. bras. med. vet. zootec ; 59(1): 203-209, fev. 2007. tab
Artículo en Portugués | VETINDEX | ID: vti-7463

RESUMEN

Foram utilizados 12 cordeiros machos, inteiros, com peso médio de 31,6kg. Os cordeiros foram alimentados com dietas à base de milho e farelo de soja, suplementadas com diferentes fontes de cálcio: calcário calcítico (CC), feno de alfafa (FA), polpa cítrica (PC) e farinha de conchas de ostras (FCO). Os animais receberam injeção de 7,4 MBq do radiofósforo (32P) e após sete dias foram abatidos para posteriores análises. Utilizou-se o delineamento em blocos ao acaso, com quatro tratamentos e três repetições. A taxa de retenção de 32P, as atividades específicas relativas e padronizadas, e a quantidade de P inorgânico nos tecidos foram iguais para todos os tratamentos (P>0,05). A comparação entre os tecidos mostrou que a concentração de P inorgânico e a taxa de retenção de 32P (P<0,01) foram mais altas nos ossos em relação aos tecidos moles (P<0,01). A retenção de 32P apresentou a seguinte ordem decrescente: rins, fígado, coração, músculos e ossos (P<0,01). A reabsorção óssea de P foi maior que a deposição de P, levando ao balanço negativo do elemento para a maioria dos animais. Concluiu-se que as diferentes fontes de cálcio não interferiram na cinética do P e que a quantidade de P ingerida não atendeu às exigências de P dos animais.(AU)


Sixteen growing rams, averaging 31.6kg were studied. They were fed diets based on corn and soya meal, supplemented with different sources of calcium: limestone (CC), alfalfa hay (FA), citrus pulp (PC) and oyster shell meal (OSM). The animals received an injection of 7.4 MBq of radioactive P (32P) and after 7 days they were slaughtered for further analyses. Experimental measurements were analyzed as a completely randomized design with four treatments and three repetitions. The rate of 32P retention, the relative specific activity, the standardized specific activity and the inorganic P in tissue were similar for all treatments (P>0.05). The comparison between tissues showed that the concentration of inorganic P and rate of 32P retention was greater in bone (P<0.01) than in soft tissue. The 32P retention presented the following decreasing order: kidney, liver, heart, muscle and bone (P<0.01). P resorption in bone was higher than P accreted in bone, leading to a negative balance of P in bone for the majority of animals. The means for P accreted in bone were 1.56, 3.29, 2.74 and 2.06g/animal and the means for P resorption in bone were 2.82, 4.51, 4.09 and 3.05g/animal for limestone (CC), alfalfa hay (FA), citrus pulp (PC) and oyster shell meal (OSM), respectively. P resorption values were higher than P accretion in bone leading to a negative balance of P for the majority of animals. It was concluded that the different sources of calcium did not interfere in the kinetics of phosphorus and the amount of P absorbed did not attend P demands of the animals.(AU)


Asunto(s)
Suplementos Dietéticos/análisis , Fósforo/administración & dosificación , Calcio de la Dieta/análisis , Calcio de la Dieta/metabolismo , Huesos/fisiología , Resorción Ósea , Ovinos
16.
J Anim Sci ; 84(10): 2787-94, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16971580

RESUMEN

The objective of the study was to revise a model of P kinetics proposed by Vitti et al. (2000) and extend its use to study Ca flows in growing sheep. Twelve Santa Ines male sheep, 8 mo of age, with average BW of 31.6 kg were injected with 32P and 45Ca to trace the movement of P and Ca in the body. The original model had 4 pools representing the gut, plasma, soft tissues, and bone. In the revised model, instantaneous values rather than averages for pool derivatives were incorporated, and the model was extended to represent absorption and excretion of phytate P explicitly. The amendments improved the model, resulting in higher flows between plasma and bone than between plasma and tissue and, therefore, a more accurate representation of P metabolism. Phosphorus and Ca metabolism were then assessed conjointly using the revised model. The results showed that P and Ca metabolism are closely related as evidenced by the ratio of these minerals in the bidirectional flows between plasma and bone and between plasma and tissue. Phytate P digestibility was 47%, and P retention was negative (-1.4 g/d), suggesting that a feed characteristic impaired P utilization and led to P deficiency. The revised model provides an improved prediction of P and Ca metabolism that can be used to assess mineral requirements and to estimate losses to the environment.


Asunto(s)
Calcio/farmacocinética , Modelos Biológicos , Fósforo/farmacocinética , Ovinos/metabolismo , Alimentación Animal/análisis , Animales , Radioisótopos de Calcio/análisis , Heces/química , Cinética , Masculino , Radioisótopos de Fósforo/análisis , Ácido Fítico/metabolismo , Ovinos/crecimiento & desarrollo
17.
Braz J Med Biol Res ; 37(11): 1713-20, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15517088

RESUMEN

Mood disorders cause many social problems, often involving family relationships. Few studies are available in the literature comparing patients with bipolar, unipolar, dysthymic, and double depressive disorders concerning these aspects. In the present study, demographic and disease data were collected using a specifically prepared questionnaire. Social adjustment was assessed using the Disability Adjustment Scale and family relationships were evaluated using the Global Assessment of Relational Functioning Scale. One hundred patients under treatment for at least 6 months were evaluated at the Psychiatric Outpatient Clinic of the Botucatu School of Medicine, UNESP. Most patients were women (82%) more than 50 (49%) years old with at least two years of follow-up, with little schooling (62% had less than 4 years), and of low socioeconomic level. Logistic regression analysis showed that a diagnosis of unipolar disorder (P = 0.003, OR = 0.075, CI = 0.014-0.403) and dysthymia (P = 0.001, OR = 0.040, CI = 0.006-0.275) as well as family relationships (P = 0.002, OR = 0.953, CI = 0914-0.992) played a significant role in social adjustment. Unipolar and dysthymic patients presented better social adjustment than bipolar and double depressive patients (P < 0.001), results that were not due to social class. These patients, treated at a teaching hospital, may represent the severest mood disorder cases. Evaluations were made knowing the diagnosis of the patients, which might also have influenced some of the results. Social disabilities among mood disorder patients are very frequent and intensive.


Asunto(s)
Relaciones Familiares , Relaciones Interpersonales , Trastornos del Humor/psicología , Ajuste Social , Adulto , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Factores Socioeconómicos , Encuestas y Cuestionarios
18.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;37(11): 1713-1720, Nov. 2004. tab
Artículo en Inglés | LILACS | ID: lil-385876

RESUMEN

Mood disorders cause many social problems, often involving family relationships. Few studies are available in the literature comparing patients with bipolar, unipolar, dysthymic, and double depressive disorders concerning these aspects. In the present study, demographic and disease data were collected using a specifically prepared questionnaire. Social adjustment was assessed using the Disability Adjustment Scale and family relationships were evaluated using the Global Assessment of Relational Functioning Scale. One hundred patients under treatment for at least 6 months were evaluated at the Psychiatric Outpatient Clinic of the Botucatu School of Medicine, UNESP. Most patients were women (82 percent) more than 50 (49 percent) years old with at least two years of follow-up, with little schooling (62 percent had less than 4 years), and of low socioeconomic level. Logistic regression analysis showed that a diagnosis of unipolar disorder (P = 0.003, OR = 0.075, CI = 0.014-0.403) and dysthymia (P = 0.001, OR = 0.040, CI = 0.006-0.275) as well as family relationships (P = 0.002, OR = 0.953, CI = 0914-0.992) played a significant role in social adjustment. Unipolar and dysthymic patients presented better social adjustment than bipolar and double depressive patients (P < 0.001), results that were not due to social class. These patients, treated at a teaching hospital, may represent the severest mood disorder cases. Evaluations were made knowing the diagnosis of the patients, which might also have influenced some of the results. Social disabilities among mood disorder patients are very frequent and intensive.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Relaciones Familiares , Relaciones Interpersonales , Trastornos del Humor/psicología , Ajuste Social , Estudios de Seguimiento , Modelos Logísticos , Escalas de Valoración Psiquiátrica , Factores Socioeconómicos , Encuestas y Cuestionarios
19.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;37(5): 737-744, May 2004. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-357539

RESUMEN

Preterm delivery is the main cause of neonatal death and ultrasonographic cervical assessment has been shown to be more accurate than digital examination in recognizing a short cervix. This is a cross-sectional study, involving 1131 women at 22-24 weeks of pregnancy, designed to determine the distribution of cervical length and to examine which variables of demographic characteristics and obstetric history increase the risk of a short cervix (15 mm or less). The distribution of maternal demographic and obstetric history characteristics among patients with cervical length ú15 mm was analyzed and compared to the findings for the general population. Risk ratios (RR) between subgroups were generated from this comparison. Median cervical length was 37 mm and in 1.5 percent of cases it was 15 mm or less. The proportion of women with a short cervix (<=15 mm) was significantly higher among patients with a low body mass index (RR = 3.5) and in those with previous fetal losses between 16-23 weeks (RR = 33.1) or spontaneous preterm deliveries between 24-32 weeks (RR = 14.1). We suggest that transvaginal sonographic measurement of cervical length be performed as part of a routine midtrimester ultrasound evaluation. There are specific variables of demographic characteristics and obstetric history which increase the risk of detecting a short cervix at 22-24 weeks.


Asunto(s)
Humanos , Femenino , Embarazo , Recién Nacido , Cuello del Útero , Trabajo de Parto Prematuro , Ultrasonografía Prenatal , Índice de Masa Corporal , Edad Gestacional , Oportunidad Relativa , Valor Predictivo de las Pruebas , Segundo Trimestre del Embarazo , Factores de Riesgo , Vagina
20.
Braz J Med Biol Res ; 37(5): 737-44, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15107937

RESUMEN

Preterm delivery is the main cause of neonatal death and ultrasonographic cervical assessment has been shown to be more accurate than digital examination in recognizing a short cervix. This is a cross-sectional study, involving 1131 women at 22-24 weeks of pregnancy, designed to determine the distribution of cervical length and to examine which variables of demographic characteristics and obstetric history increase the risk of a short cervix (15 mm or less). The distribution of maternal demographic and obstetric history characteristics among patients with cervical length pound 15 mm was analyzed and compared to the findings for the general population. Risk ratios (RR) between subgroups were generated from this comparison. Median cervical length was 37 mm and in 1.5% of cases it was 15 mm or less. The proportion of women with a short cervix (< or =15 mm) was significantly higher among patients with a low body mass index (RR = 3.5) and in those with previous fetal losses between 16-23 weeks (RR = 33.1) or spontaneous preterm deliveries between 24-32 weeks (RR = 14.1). We suggest that transvaginal sonographic measurement of cervical length be performed as part of a routine midtrimester ultrasound evaluation. There are specific variables of demographic characteristics and obstetric history which increase the risk of detecting a short cervix at 22-24 weeks.


Asunto(s)
Cuello del Útero/diagnóstico por imagen , Nacimiento Prematuro/diagnóstico , Ultrasonografía Prenatal/métodos , Índice de Masa Corporal , Cuello del Útero/anatomía & histología , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Recién Nacido , Oportunidad Relativa , Valor Predictivo de las Pruebas , Embarazo , Segundo Trimestre del Embarazo , Nacimiento Prematuro/prevención & control , Factores de Riesgo , Vagina/diagnóstico por imagen
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