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3.
Lett Appl Microbiol ; 73(2): 237-246, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33966285

RESUMO

Enterococcus species are present in the microbiota of humans and animals and have also been described in the environment. Among the species, Enterococcus faecium is one of the main pathogens associated with nosocomial infections worldwide. Enterococcus faecium isolates resistant to different classes of antimicrobials have been increasingly reported, including multidrug-resistant (MDR) isolates in environmental sources, which is worrying. Therefore, this study aimed to characterize E. faecium isolates obtained from soil and water samples regarding antimicrobial resistance and virulence determinants. A total 40 E. faecium isolates were recovered from 171 environmental samples. All isolates were classified as MDR, highlighting the resistance to the fluoroquinolones class, linezolid and vancomycin. Furthermore, high-level aminoglycoside resistance and high-level ciprofloxacin resistance were detected in some isolates. Several clinically relevant antimicrobial resistance genes were found, including vanC1, ermB, ermC, mefAE, tetM, tetL, ant(6')-Ia, ant(4')-Ia, aph(3')-IIIa and aac(6')-Ie-aph(2″)-Ia. Three virulence genes were detected among the MDR E. faecium isolates, such as esp, gelE and ace. The results of this study contribute to a better understanding of MDR E. faecium isolates carrying antimicrobial resistance and virulence genes in environmental sources and report for the first time in the world the presence of vanC1-producing E. faecium isolated from soil.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Aminoglicosídeos/farmacologia , Ciprofloxacina/farmacologia , Infecção Hospitalar/microbiologia , DNA Bacteriano , Enterococcus faecium/isolamento & purificação , Microbiologia Ambiental , Fluoroquinolonas/farmacologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Linezolida/farmacologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência , Vancomicina/farmacologia , Virulência , Fatores de Virulência/genética
4.
Vet J ; 217: 119-125, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27810202

RESUMO

Sheep are used in many countries as food and for manufacturing bioproducts. However, when these animals consume animal by-products (ABP), which is widely prohibited, there is a risk of transmitting scrapie - a fatal prion disease in human beings. Therefore, it is essential to develop sensitive methods to detect previous ABP intake to select safe animals for producing biopharmaceuticals. We used stable isotope ratio mass spectrometry (IRMS) for 13C and 15N to trace animal proteins in the serum of three groups of sheep: 1 - received only vegetable protein (VP) for 89 days; 2 - received animal and vegetable protein (AVP); and 3 - received animal and vegetable protein with animal protein subsequently removed (AVPR). Groups 2 and 3 received diets with 30% bovine meat and bone meal (MBM) added to a vegetable diet (from days 16-89 in the AVP group and until day 49 in the AVPR group, when MBM was removed). The AVPR group showed 15N equilibrium 5 days after MBM removal (54th day). Conversely, 15N equilibrium in the AVP group occurred 22 days later (76th day). The half-life differed between these groups by 3.55 days. In the AVPR group, 15N elimination required 53 days, which was similar to this isotope's incorporation time. Turnover was determined based on natural 15N signatures. IRMS followed by turnover calculations was used to evaluate the time period for the incorporation and elimination of animal protein in sheep serum. The δ13C and δ15N values were used to track animal protein in the diet. This method is biologically and economically relevant for the veterinary field because it can track protein over time or make a point assessment of animal feed with high sensitivity and resolution, providing a low-cost analysis coupled with fast detection. Isotopic profiles could be measured throughout the experimental period, demonstrating the potential to use the method for traceability and certification assessments.


Assuntos
Ração Animal/análise , Dieta/veterinária , Proteínas Alimentares/análise , Espectrometria de Massas/veterinária , Ovinos , Animais , Isótopos de Carbono/análise , Espectrometria de Massas/métodos , Isótopos de Nitrogênio/análise
5.
Ecotoxicology ; 23(9): 1659-70, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25139030

RESUMO

Fipronil is a phenylpyrazole insecticide that is widely used in Brazilian agriculture for pest control. Although honeybees are not targets of fipronil, studies indicate that this pesticide can be harmful to honeybees. To assess the effects of fipronil in the brain of Africanized Apis mellifera workers, this study focused on the toxico-proteome profiling of the brain of newly emerged and aged honeybee workers that were exposed to a sub-lethal dose (10 pg fipronil per day. i.e. (1)/100 of LD50/bee/day during 5 days) of the insecticide. Proteomic analysis identified 25 proteins that were differentially up-regulated or down-regulated when the fipronil-exposed and non-exposed groups were compared. These proteins are potentially related to pathogen susceptibility, neuronal chemical stress, neuronal protein misfolding, and occurrence of apoptosis, ischemia, visual impairment, damaged synapse formation, brain degeneration, memory and learning impairment. The exposure of honeybees to a very low dose of fipronil, even for a short period of time (5 days), was sufficient to cause a series of important neuroproteomic changes in the brains of honeybees.


Assuntos
Abelhas , Encéfalo/efeitos dos fármacos , Inseticidas/toxicidade , Proteoma/efeitos dos fármacos , Pirazóis/toxicidade , Animais , Encéfalo/metabolismo , Brasil , Dose Letal Mediana , Testes de Toxicidade Subaguda
6.
Artigo em Inglês | LILACS, VETINDEX | ID: lil-639470
8.
J. venom. anim. toxins incl. trop. dis ; 17(4): 364-377, 2011. ilus
Artigo em Inglês | LILACS | ID: lil-623499

RESUMO

Venoms represent a huge and essentially unexplored reservoir of bioactive components that may cure diseases that do not respond to currently available therapies. This review select advances reported in the literature from 2000 to the present about the new scenario of Hymenoptera venom composition. On account of new technologies in the proteomic approach, which presents high resolution and sensitivity, the combination of developments in new instruments, fragmentation methods, strategic analysis, and mass spectrometry have become indispensable tools for interrogation of protein expression, molecule interaction, and post- translational modifications. Thus, the biochemical characterization of Hymenoptera venom has become a major subject of research in the area of allergy and immunology, in which proteomics has been an excellent alternative to assist the development of more specific extracts for diagnosis and treatment of hypersensitive patients to Hymenoptera venoms.


Assuntos
Animais , Venenos de Abelha , Espectrometria de Massas/métodos , Himenópteros , Hipersensibilidade , Proteômica , Venenos de Vespas
9.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 17(4): 364-377, 2011. ilus
Artigo em Inglês | VETINDEX | ID: vti-7936

RESUMO

Venoms represent a huge and essentially unexplored reservoir of bioactive components that may cure diseases that do not respond to currently available therapies. This review select advances reported in the literature from 2000 to the present about the new scenario of Hymenoptera venom composition. On account of new technologies in the proteomic approach, which presents high resolution and sensitivity, the combination of developments in new instruments, fragmentation methods, strategic analysis, and mass spectrometry have become indispensable tools for interrogation of protein expression, molecule interaction, and post- translational modifications. Thus, the biochemical characterization of Hymenoptera venom has become a major subject of research in the area of allergy and immunology, in which proteomics has been an excellent alternative to assist the development of more specific extracts for diagnosis and treatment of hypersensitive patients to Hymenoptera venoms.(AU)


Assuntos
Animais , Venenos de Vespas , Himenópteros/imunologia , Proteômica/tendências
10.
Braz J Biol ; 69(1): 129-36, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19347155

RESUMO

This work aimed to evaluate the effects of simulated drift of glyphosate on the morphoanatomy of three eucalypt clones and to correlate the intoxication symptoms on a microscopic scale with those observed in this visual analysis. The effects of glyphosate drift were proportional to the five doses tested, with Eucalyptus urophylla being more tolerant to the herbicide than E. grandis and urograndis hybrid. The symptoms of intoxication which were similar for the different clones at 7 and 15 days after application were characterized by leaf wilting, chlorosis and curling and, at the highest rates, by necrosis, leaf senescence and death. Anatomically glyphosate doses higher than 86.4 g.ha-1 caused cellular plasmolysis, hypertrophy and hyperplasia, formation of the cicatrization tissue and dead cells on the adaxial epidermis. The spongy parenchyma had a decrease, and the palisade parenchyma and leaf blade thickness had an increase. The increased thickness in leaf blade and palisade parenchyma may be related to the plant response to glyphosate action, as a form of recovering the photosynthetically active area reduced by necroses and leaf senescence caused by the herbicide.


Assuntos
Eucalyptus/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/toxicidade , Folhas de Planta/efeitos dos fármacos , Clonagem de Organismos , Relação Dose-Resposta a Droga , Eucalyptus/anatomia & histologia , Eucalyptus/citologia , Eucalyptus/genética , Glicina/toxicidade , Folhas de Planta/anatomia & histologia , Folhas de Planta/citologia , Glifosato
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