RESUMO
The aim of this study was to investigate the effects of N-acetylcysteine (NAC) on antibiotic susceptibility of bovine mastitis pathogens including Staphylococcus aureus, Streptococcus dysgalactiae, Escherichia coli, and Streptococcus agalactiae. Minimum inhibitory concentrations (MIC) were tested by the agar-based E-test method. The presence of 10mM NAC reduced the MIC of penicillin and ampicillin but enhanced the MIC of erythromycin and ciprofloxacin for all of the strains. In addition, NAC-mediated modulation of MIC of kanamycin, tetracycline, and vancomycin was diverse, depending on the target bacterial pathogen and antibiotic being used. The results suggest that NAC is an important modulator of antibiotic activity against the major bovine mastitis pathogens.
Assuntos
Mastite Bovina/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Antibacterianos/farmacologia , Bovinos , Feminino , Testes de Sensibilidade Microbiana , Streptococcus/efeitos dos fármacosRESUMO
Recent data have indicated that inflammation may have an important correlation with obstructive sleep apnea (OSA). Studies have indicated a relationship between OSA and TNF-α gene polymorphisms. Zinc finger protein 36 (ZFP36) regulates TNF-α mRNAs. However, ZFP36 gene polymorphisms have not been investigated in OSA. Therefore, we conducted the present case-control study to assess whether variances in ZFP36 gene polymorphisms account for differences in TNF-α levels in patients with moderate-to-severe OSA. This case-control study aims to investigate the relationship between genetic variations in the ZFP36 gene and moderate-to-severe OSA. Three common single nucleotide polymorphisms of the ZFP36 gene (rs251864, rs3746083, and rs17879933) were evaluated in a group of patients with moderate-to-severe OSA (N = 408) and in a control group (N = 394) by using TaqMan polymerase chain reaction analysis. The moderate-to-severe OSA group and the control group exhibited significant differences in the distributions of rs251864 and rs17879933 genotypes and alleles (P < 0.05). TNF-α levels were significantly different not only among the three rs251864 genotypes but also between the II genotype and the DD + ID genotypes of rs17879933. However, no significant differences in sleep apnea parameters in the three ZFP36 gene polymorphisms were observed. Logistic regression analyses demonstrated that TNF-α and the three ZFP36 gene polymorphisms were not independently associated with OSA. ZFP36 might be involved in TNF-α regulation. However, ZFP36 gene variants were not independent risk factors for moderate-to-severe OSA.
Assuntos
Polimorfismo de Nucleotídeo Único , RNA Mensageiro/genética , Apneia Obstrutiva do Sono/genética , Tristetraprolina/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Genótipo , Humanos , Inflamação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polissonografia , RNA Mensageiro/metabolismo , Fatores de Risco , Índice de Gravidade de Doença , Transdução de Sinais , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/patologia , Tristetraprolina/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
(1) This in vivo trial was conducted to study the effects of polysaccharide extracts of two mushrooms, Lentinus edodes (LenE) and Tremella fuciformis (TreE), and a herb, Astragalus membranaceus (AstE) on growth performance, and the weights of organs and the gastrointestinal tract (GIT) of broiler chickens. (2) Three extracts (LenE, TreE and AstE) were supplemented at inclusion rates of 0.5, 1, 2, 3 and 4 g/kg from 7 to 14 d of age and compared with an antibiotic treatment group (20 mg/kg, virginiamycin (VRG) as well as a group of non-supplemented birds. (3) Body weight (BW) gain, feed intake and feed conversion ratio (FCR) of the extract-supplemented groups were not significantly different from those of the antibiotic group. Significant effects of type of extract and concentration on growth performance were found from 7 to 28 d of age. Generally, birds fed with LenE showed higher BW gain and lower FCR from 7 to 28 d of age than those fed with TreE and AstE and 2 g/kg LenE was considered the optimal inclusion rate for enhanced broiler growth. However, the extracts had no significant effect on the relative weights of organs and GIT compared with the antibiotic group. (4) The birds fed the extracts showed better growth performance than the non-supplemented birds, but were not significantly different from those fed VRG. Of the three extracts, LenE appeared to be a potential growth promoter. Future studies are needed to investigate whether the extracts can be used as alternatives for antibiotic growth promoters in challenged birds, and to elucidate the mechanisms for potentially enhanced growth performance in poultry.
