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1.
Foodborne Pathog Dis ; 12(6): 479-85, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25974222

RESUMO

The frequent use of antimicrobials in commercial poultry production has raised concerns regarding the potential impact of antimicrobials on human health due to selection for resistant bacteria. Several studies have reported similarities between extraintestinal pathogenic Escherichia coli (ExPEC) strains isolated from birds and humans, indicating that these contaminant bacteria in poultry may be linked to human disease. The aim of our study was to analyze the frequency of antimicrobial resistance and virulence factors among E. coli strains isolated from commercial chicken carcasses in Paraná, Brazil, in 2007 and 2013. A total of 84 E. coli strains were isolated from chicken carcasses in 2007, and 121 E. coli strains were isolated in 2013. Polymerase chain reaction was used to detect virulence genes (hlyF, iss, ompT, iron, and iutA) and to determine phylogenetic classification. Antimicrobial susceptibility testing was performed using 15 antimicrobials. The strains were also confirmed as extended-spectrum ß-lactamase (ESBL)-producing E. coli with phenotypic and genotypic tests. The results indicated that our strains harbored virulence genes characteristic of ExPEC, with the iutA gene being the most prevalent. The phylogenetic groups D and B1 were the most prevalent among the strains isolated in 2007 and 2013, respectively. There was an increase in the frequency of resistance to a majority of antimicrobials tested. An important finding in this study was the large number of ESBL-producing E. coli strains isolated from chicken carcasses in 2013, primarily for the group 2 cefotaximase (CTX-M) enzyme. ESBL production confers broad-spectrum resistance and is a health risk because ESBL genes are transferable from food-producing animals to humans via poultry meat. These findings suggest that our strains harbored virulence and resistance genes, which are often associated with plasmids that can facilitate their transmission between bacteria derived from different hosts, suggesting zoonotic risks.


Assuntos
Antibacterianos/farmacologia , Galinhas/microbiologia , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Carne/microbiologia , Fatores de Virulência/metabolismo , Animais , Anti-Infecciosos/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Brasil , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Inspeção de Alimentos , Microbiologia de Alimentos/tendências , Isoenzimas/genética , Isoenzimas/metabolismo , Carne/economia , Tipagem Molecular , Filogenia , Fatores de Virulência/genética , beta-Lactamases/genética , beta-Lactamases/metabolismo
2.
Diabetes Metab Syndr ; 13(1): 554-558, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30641764

RESUMO

Metabolic Syndrome (MetS) is multivariate disease, clustered with socioeconomic and behavioral risk factors. Investigations about epidemiology estimative could be a prevention strategy. AIM: to investigate the prevalence of metabolic syndrome and its associated factors in adult population in Fernando de Noronha Archipelago (PE-Brazil). METHODS: A cross-sectional study was performed on a representative sample (N = 375) of adult residents of the region, aged 24-59 years, were harmonized according to the International Diabetes Federation (IDF) criteria. RESULTS: The prevalence of metabolic syndrome was 45 (12%) and, the age was associated with MetS, which increases the chances to MetS development around 3% respectively (OR: 1.03; CI 95%: 1.002-1.070 P 0.0384). Waist circumference was elevated in female population 266 (70.74%), however, levels of fasting blood glucose (304 [80.85%]), blood pressure (375 [100%]), TG (302 [80.32]), and low HDLc (297 [78.99]) presented normal biochemical values. There is no significative difference for male and female gender and, the social and behavior factors did not present significative association. CONCLUSION: The Fernando de Noronha presents lower prevalence of MetS thus, shows associations for elderly people. The waist circumference was elevated on female population. The results of this study provide further evidence and underscore the need for public health strategies that include education about MetS, promotion of cardiometabolic health, and prevention of undesirable outcomes such as diabetes and cardiovascular disease.


Assuntos
Glicemia/metabolismo , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Circunferência da Cintura/fisiologia , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
3.
Biomed Res Int ; 2015: 618752, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26579536

RESUMO

Microbiological contamination in commercial poultry production has caused concerns for human health because of both the presence of pathogenic microorganisms and the increase in antimicrobial resistance in bacterial strains that can cause treatment failure of human infections. The aim of our study was to analyze the profile of antimicrobial resistance and virulence factors of E. coli isolates from chicken carcasses obtained from different farming systems (conventional and free-range poultry). A total of 156 E. coli strains were isolated and characterized for genes encoding virulence factors described in extraintestinal pathogenic E. coli (ExPEC). Antimicrobial susceptibility testing was performed for 15 antimicrobials, and strains were confirmed as extended spectrum of ß-lactamases- (ESBLs-) producing E. coli by phenotypic and genotypic tests. The results indicated that strains from free-range poultry have fewer virulence factors than strains from conventional poultry. Strains from conventionally raised chickens had a higher frequency of antimicrobial resistance for all antibiotics tested and also exhibited genes encoding ESBL and AmpC, unlike free-range poultry isolates, which did not. Group 2 CTX-M and CIT were the most prevalent ESBL and AmpC genes, respectively. The farming systems of poultries can be related with the frequency of virulence factors and resistance to antimicrobials in bacteria.


Assuntos
Farmacorresistência Bacteriana/fisiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Doenças das Aves Domésticas/microbiologia , Aves Domésticas/microbiologia , Fatores de Virulência/metabolismo , Animais , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Doenças das Aves Domésticas/tratamento farmacológico
4.
Biosens Bioelectron ; 14(1): 53-9, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10028649

RESUMO

The Python infrared-sensitive pit organ is a natural infrared imager that combines high sensitivity, ambient temperature function, microscopic dimensions, and self-repair. We are investigating the spectral sensitivity and signal transduction process in snake infrared-sensitive neurons, neither of which is understood. For example, it is unknown whether infrared receptor neurons function on a thermal or a photic mechanism. We imaged pit organs in living Python molurus and Python regius using infrared-sensitive digital video cameras. Pit organs were significantly more absorptive and/or emissive than surrounding tissues in both 3-5 microns and 8-12 microns wavelength ranges. Pit organs exhibited greater absorption/emissivity in the 8-12 microns range than in the 3-5 microns range. To directly test the relationship between photoreceptors and pit organ infrared-sensitive neurons, we performed immunocytochemistry using antisera directed against retinal photoreceptor opsins. Retinal photoreceptors were labeled with antisera specific for retinal opsins, but these antisera failed to label terminals of infrared-sensitive neurons in the pit organ. Infrared-receptive neurons were also distinguished from retinal photoreceptors on the basis of their calcium-binding protein content. These results indicate that the pit organ absorbs infrared radiation in two major atmospheric transmission windows, one of which (8-12 microns) matches emission of targeted prey, and that infrared receptors are biochemically distinct from retinal photoreceptors. These results also provide the first identification of prospective biochemical components of infrared signal transduction in pit organ receptor neurons.


Assuntos
Técnicas Biossensoriais , Boidae/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Células Fotorreceptoras de Vertebrados/efeitos da radiação , Animais , Boidae/anatomia & histologia , Proteínas de Ligação ao Cálcio/fisiologia , Imuno-Histoquímica , Raios Infravermelhos , Microscopia Eletrônica , Células Fotorreceptoras de Vertebrados/ultraestrutura , Opsinas de Bastonetes/metabolismo , Transdução de Sinais
5.
Pesqui. vet. bras ; Pesqui. vet. bras;37(12): 1395-1400, dez. 2017. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-895397

RESUMO

Celulite aviária é uma enfermidade de grande importância para a avicultura mundial, sendo relacionada principalmente à Escherichia coli (E. coli). Neste estudo foi comparada a susceptibilidade de duas linhagens de aves no desenvolvimento da celulite diante do desafio com diferentes concentrações de E. coli. Além disso, foi avaliada a relação dos genes iss e iutA com a patogenicidade de amostras de E. coli de diferentes origens (fecal/casos clínicos) em pintinhos e com a reprodução experimental da doença em aves de 35 dias de idade. Através da inoculação de frangos de corte (Cobb/Ross) com diferentes níveis de desafio (105 a 108 UFC/mL) de E. coli, não foram observadas diferenças significativas entre as linhagens quanto à sensibilidade à dermatite necrótica para a mesma dosagem (p≤0,05). A detecção dos genes iss e iutA demonstrou que estes estiveram presentes somente nas amostras provenientes de casos clínicos. Da mesma forma, estes isolados foram considerados de alta patogenicidade para pintinhos (>80% letalidade), levando a formação de áreas de lesão mais extensas (≥3cm2) em aves de 35 dias, quando comparado às amostras de origem fecal (p≤0,05). Ainda, as diferenças com relação ao tamanho de lesão foram constatadas também entre os isolados de mesma origem (p≤0,05). Desta forma, a linhagem não pode ser considerada um fator primordial para o desenvolvimento de dermatite necrótica em frangos. Ainda, sugere-se que os genes iss e iutA, quando presentes em conjunto ou isoladamente, poderiam ser considerados marcadores de virulência em cepas de E. coli causadoras de celulite aviária.(AU)


Avian cellulitis is a disease of great importance for the global poultry industry, being mainly related to Escherichia coli. In this study the susceptibility of two lineages of broilers in the development of cellulite was compared to the challenge with different concentrations of E. coli. In addition, it evaluated the relationship of the iss and iutA genes with pathogenicity of E. coli samples from different origins (fecal/clinical cases) in chicks and with the experimental reproduction of disease in 35-day-old broilers. By inoculating broilers (Cobb/Ross) with different levels of challenge (105-108 CFU/mL) of E. coli, no significant differences had been observed between strains for sensitivity to necrotic dermatitis for the same dosage (p≤0.05). Detection of the iss and iutA genes showed that they were only present in samples from clinical cases. Likewise, these strains were considered high pathogenicity for chickens (>80% lethality), leading to the formation of more extensive lesion areas (≥3cm2) at 35 days of birds compared to the samples from fecal origin (p≤0.05). Still, the differences with respect to lesion size were also found among isolates of the same origin (p≤0,05). Thus, the lineage can not be considered a primary factor in the development of necrotic dermatitis in broilers. Furthermore, it is suggested that iss and iutA genes, when present together or separately, could be considered as virulence markers for E. coli strains that cause avian cellulite.(AU)


Assuntos
Animais , Galinhas/genética , Fatores de Virulência/genética , Suscetibilidade a Doenças/veterinária , Escherichia coli/genética , Celulite/genética , Celulite/veterinária , Dermatite/veterinária
6.
Pesqui. vet. bras ; Pesqui. vet. bras;36(5): 357-362, graf
Artigo em Inglês | LILACS | ID: lil-787589

RESUMO

This study represents the first phylogenetic analysis of avian poxvirus recovered from turkeys in Brazil. The clinical disorders related to fowlpox herein described occurred in a turkey housing system. The birds displaying characteristic pox lesions which were observed on the neck, eyelids and beak of the turkeys. Four affected turkeys were randomly chosen, euthanized and necropsied. Tissues samples were submitted for histopathological analysis and total DNA was further extracted, amplified by conventional PCR, sequenced and phylogenetically analyzed. Avian poxviruses specific PCR was performed based on P4b core protein gene sequence. The histological analysis revealed dermal inflammatory process, granulation tissue, hyperplasia of epithelial cells and inclusion bodies. The P4b gene was detected in all samples. Sequencing revealed a 100% nucleotide and amino acid sequence identity among the samples, and the sequences were deposited in GenBank®. The four Avian poxviruses fragments sequenced in this study clustered along the A1 clade of avipoxviruses, and were classified as Avipoxvirus (APV). Additional studies, such as virus isolation, PCR and sequencing includinga large number of specimens from the Brazilian turkey production must be conducted due to the hazardous risk that poxvirus infections may cause to the Brazilian poultry production scenario, given that Brazil's turkey production attracts attention due to its economic importance worldwide. Our findings point to the need to identify the prevalence of APV in Brazilian turkey production, to perform risk assessment studies and continued surveillance of APV infections in both wild and commercial avian species.


Este trabalho representa a primeira análise filogenética de Poxvirus aviário detectado em perus no Brasil. Os distúrbios clínicos relacionados com bouba aviária aqui descritos ocorreram em um sistema de alojamento de perus. As aves apresentaram lesões características de varíola observadas no pescoço, pálpebras e bico das aves. Quatro perus com sinais característicos foram escolhidos aleatoriamente, sacrificados e submetidos à autópsia. Amostras de tecido foram submetidas à análise histopatológica e o DNA total foi extraído, amplificado por PCR convencional e os amplicons foram sequenciados e analisados ​​filogeneticamente. A PCR específica para Poxvírus aviário foi realizada com base na seqüência do gene da proteína do núcleo P4b. A análise histológica revelou um processo inflamatório dérmico, tecido de granulação, hiperplasia de células epiteliais e corpúsculos de inclusão. O gene P4b foi detectado em todas as amostras. O sequenciamento revelou uma identidade entre nucleotídeos e aminoácido de 100% entre as amostras e as sequências foram depositadas no GenBank®. Os quatro fragmentos de poxvírus aviário sequenciado neste estudo foram agrupados no clado A1 de avipoxvirus e foram classificados como Avipoxvirus (APV). Estudos adicionais, como isolamento viral, PCR e sequenciamento, incluindo um grande número de perus da produção brasileira devem ser conduzidos devido ao grave risco que a infecção por poxvírus pode causar ao cenário de produção avícola brasileira, tendo em vista que a produção brasileira de perus atrai atenção devido a sua importância mundial. Nossos resultados apontam para a necessidade de identificar a prevalência da APV na produção de peru no Brasil, para realizar estudos de avaliação de risco e continuada monitoração de infecções por APV nas espécies de aves comerciais e silvestres.


Assuntos
Animais , Avipoxvirus/isolamento & purificação , Filogenia , Perus/microbiologia , Poxviridae/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária
7.
Artigo em Inglês | MEDLINE | ID: mdl-11367086

RESUMO

AIDS: Charles T. Kelly, manager at Mobilizing Talents and Skills (MTS), an agency that provides people living with HIV/AIDS with job training and job search guidance, offers insights on returning to work. The ability to work is more prevalent now for PWAs thanks to better treatments. In making the decision to work, consideration must be given to health status, possible changes in benefits as wages increase, and personal goals. PWAs also need to evaluate their current skills to see where they fit in the job market, and anticipate how to handle gaps on their resume due to illness. The best way to seek a new job is to network among friends and professional associates. Although many unique issues must be considered when a PWA decides to see employment, returning to work can contribute to improved health and self-esteem.^ieng


Assuntos
Emprego , Infecções por HIV/psicologia , Associações de Consumidores , Tomada de Decisões , Humanos , Estilo de Vida , Salários e Benefícios , Estados Unidos
8.
Can J Microbiol ; 24(10): 1164-72, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31973

RESUMO

Bacillus sp. RK9 was isolated from soil and produced a constitutive polygalacturonate lyase. Production of the enzyme required the presence of complex nitrogen (peptone and yeast extract). Highest activity was obtained with an initial pH of 9.7. The organism was alkalophilic. No growth occurred below pH 7.5. The enzyme was purified by salt precipitation and diethylaminoethyl (DEAE) cellulose ion-exchange chromatography. The pH optimum for activity was 10.0 in 0.01 M glycine-NaOH buffer. Calcium alone, of divalent cations, activated the enzyme by 2.9-fold. Complete inhibition of enzyme activity was achieved by 1 mM ethylenediaminetetraacetic acid (EDTA). Hydrolysis of substrate occurred in a random fashion and the enzyme was 50% more active towards acid soluble pectic acid (ASPA) than towards sodium polypectate.


Assuntos
Bacillus/enzimologia , Polissacarídeo-Liases/biossíntese , Microbiologia do Solo , Meios de Cultura , Ácido Edético/farmacologia , Concentração de Íons de Hidrogênio , Pectinas/metabolismo , Polissacarídeo-Liases/metabolismo , Especificidade por Substrato
9.
Clin Chem ; 23(1): 64-8, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-832374

RESUMO

We describe a combined gas-chromatographic mass-spectrometric method for determination of theophylline in whole blood. With use of a probability-based matching approach, the extensive gas-chromatographic interference did not affect mass-spectrometric quantitation of theophylline. Concentrations expected and found were linearly related from 1 to 60 mg/liter; the run-to-run coefficient of variation was less than 8%, within-run less than 6%. Some other xan-thines and drugs frequently co-administered with theophylline did not affect results. Only 0.2 ml of blood is required, which makes the procedure useful for monitoring theophylline in newborns and pediatric populations.


Assuntos
Teofilina/sangue , Cromatografia Gasosa/métodos , Estudos de Avaliação como Assunto , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Microquímica
10.
Eur J Biochem ; 203(1-2): 225-31, 1992 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1730228

RESUMO

Bacillus stearothermophilus NCIB 11412 produces a highly thermostable alpha-amylase. The enzyme displayed half-lives of irreversible thermoinactivation at 90 degrees C of 1.9 min and 12.5 min at pH 5.0 and pH 8.0, respectively. Molecular mechanisms of irreversible thermoinactivation were investigated. At both pH 5.0 and pH 8.0 irreversible thermoinactivation was due to heat-induced breakdown of non-covalent interaction within the protein molecule, resulting in unfolding and consequent formation of altered structures. Hydrophobic interactions were shown to be the most important non-covalent mechanisms involved in this phenomenon. Although not dramatically effecting the rates of irreversible thermoinactivation, electrostatic interactions, including hydrogen bonding, were also shown to have a contributory role in this process. At pH 8.0 a covalent mechanism, that of oxidation of thiols was also shown to be of secondary importance to hydrophobic interactions in the irreversible thermoinactivation of this enzyme.


Assuntos
Geobacillus stearothermophilus/enzimologia , alfa-Amilases/antagonistas & inibidores , Acetamidas/farmacologia , Acetilação , Eletricidade , Meia-Vida , Temperatura Alta , Cinética , Conformação Proteica , Especificidade por Substrato , alfa-Amilases/metabolismo
11.
Appl Microbiol Biotechnol ; 51(2): 170-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10091322

RESUMO

The amylopullulanse produced by Bacillus sp. DSM 405 was purified to homogeneity. It exhibited dual activity, cleaving the alpha 1-4 bonds in starch, releasing a range of malto-oligosaccharides, and also cleaving the alpha 1-6 bonds in pullulan, releasing maltotriose as the sole end-product. The enzyme was a glycoprotein and had a relative molecular mass of 126,000 and an isoelectric point of 4.3. While the enzyme was optimally active on starch at pH 6.5 and at pH 6.0 on pullulan, activity on both substrates was maximal at 70 degrees C. Kinetic analyses of the enzyme in a system that contained both starch and pullulan as two competing substrates demonstrated the dual specificity of the enzyme. Chemical modification of the carboxyl groups within the active centre of the protein showed that one active site was responsible for hydrolysis of the alpha 1-4 and alpha 1-6 bonds in starch and pullulan respectively. This is the first comprehensive investigation of an amylopullulanse produced by an aerobic bacterium, showing a single active site responsible for both activities.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias , Glicosídeo Hidrolases , Bacillus/crescimento & desenvolvimento , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Carbodi-Imidas/farmacologia , Ativação Enzimática , Glucanos/metabolismo , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/metabolismo , Glicosídeo Hidrolases/farmacologia , Cinética , Amido/metabolismo , alfa-Amilases/metabolismo
12.
Appl Microbiol Biotechnol ; 48(4): 504-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9390460

RESUMO

The alpha-amylase of Streptomyces sp. IMD 2679 was subject to catabolite repression. Four different growth rates were achieved when the organism was grown at 40 degrees C and 55 degrees C in the presence and absence of cobalt, with an inverse relationship between alpha-amylase production and growth rate. Highest alpha-amylase yields (520 units/ml) were obtained at the lowest growth rate (0.062 h-1), at 40 degrees C in the absence of cobalt, while at the highest growth rate (0.35 h-1), at 55 degrees C in the presence of cobalt, alpha-amylase production was decreased to 150 units/ml. As growth rate increased, the rate of specific utilisation of the carbon source maltose also increased, from 46 to 123 micrograms maltose (mg biomass)-1 h-1. The pattern and levels of alpha-glucosidase (the enzyme degrading maltose) detected intracellularly in each case, indicate that growth rate effectively controls the rate of feeding of glucose to the cell, and thus catabolite repression.


Assuntos
Proteínas de Bactérias/biossíntese , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Streptomyces/enzimologia , alfa-Amilases/biossíntese , Proteínas de Bactérias/genética , Meios de Cultura , Maltose/metabolismo , Streptomyces/crescimento & desenvolvimento , alfa-Amilases/genética
13.
Appl Microbiol Biotechnol ; 39(1): 31-5, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7763549

RESUMO

The alpha-amylase of Thermomonospora curvata catalyses the formation of very high levels of maltose from starch (73%, w/w) without the attendant production of glucose. The enzyme was produced extracellularly in high yield during batch fermentation in a 5-1 fermentor. Purification was achieved by ammonium sulphate fractionation, Superose-12 gel filtration and DEAE-Sephacel ion-exchange chromatography. The enzyme exhibited maxima for activity at pH 6.0 and 65 degrees C, had a relative molecular mass of 60,900-62,000 and an isoelectric point at 6.2. The exceptionally high levels of maltose produced and the unique action pattern exhibited on starch and related substrates indicate a very unusual maltogenic system. The predominance of maltose as the final end-product may be explained by the participation of reactions other than simple hydrolysis and the preferential cleavage of maltotriose from higher maltooligosaccharides. The enzyme exhibits very low affinity for maltotriose (Km = 7.7 x 10(-3) M) and its conversion to maltose is achieved by synthetic followed by hydrolytic events, which result in the very high levels of maltose observed and preclude glucose formation. This system is distinguished from other very high maltose-producing amylases by virtue of its high temperature maximum, very low affinity for maltotriose and the absence of glucose in the final saccharide mixture.


Assuntos
Actinomycetales/enzimologia , alfa-Amilases/metabolismo , Maltose/análogos & derivados , Maltose/metabolismo , Modelos Biológicos , Oligossacarídeos/metabolismo , Amido/metabolismo , Trissacarídeos/metabolismo , alfa-Amilases/isolamento & purificação
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