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1.
Vet Immunol Immunopathol ; 235: 110235, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33838543

RESUMO

The aim of this study was to identify virulence factors that have high immunogenicity. An in vivo-expressed Staphylococcus aureus antigen was identified by probing bacteriophage expression libraries of S. aureus with antibodies in bovine mastitis milk. Eighteen clones were isolated, and their proteins were identified as 5 characterised proteins (IsdA, Protein A, IsdB, autolysin, and imidazole glycerol phosphate dehydratase) and 13 hypothetical proteins. We focused on IsdA, IsdB, and IsdH as virulence factors that have a high immunogenicity and are capable of inducing a specific humoral immune response in S. aureus-infected quarters. The optical density (OD) values of IsdA and IsdB IgA and IgG antibodies in milk affected by naturally occurring mastitis caused by S. aureus increased significantly compared to those in healthy milk. In the experimental infection study, the OD values of IsdA- and B-specific IgA and IgG antibodies were significantly increased from 2 to 4 weeks after S. aureus infection compared to day 0 (P < 0.05). On the other hand, we demonstrated that milk from natural and experimental intramammary infections caused by S. aureus are associated with significantly higher IgA levels against IsdH (P < 0.05), but no significant change in IgG levels. Our findings facilitated our understanding of the pathogenicity of S. aureus in bovine mastitis, as well as the mechanisms by which specific humoral immune responses to S. aureus infection are induced. In addition, the results obtained could provide insight into how bovine mastitis can be controlled, for example, through vaccination.


Assuntos
Anticorpos Antibacterianos/análise , Antígenos de Bactérias/imunologia , Imunoglobulina A/imunologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Leite/imunologia , Staphylococcus aureus/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/classificação , Proteínas de Transporte de Cátions/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Feminino , Imunidade Humoral , Imunoglobulina A/análise , Receptores de Superfície Celular/imunologia
2.
Toxicol Appl Pharmacol ; 222(2): 152-8, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17555784

RESUMO

Cisplatin (cis-diaminedichloroplatinum (II) or CDDP) (a widely used platinum-containing anticancer drug) is nephrotoxic and has a low percentage of tolerance in patients during chemotherapy. The active hexose correlated compound (AHCC) is an extract of Basidiomycotina marketed as a supplement for cancer patients due to its nutrients and fibre content and its ability to strengthen and optimize the capacity of the immune system. The possibility that AHCC could reduce the side effects of cisplatin was assessed in the tumor-bearing BALB/cA mice on the basis of the ability to ameliorate the cisplatin-induced body weight loss, anorexia, nephrotoxicity and hematopoietic toxicity. Although cisplatin (8 mg/kg body weight) reduced the size and weight of the solid tumors, supplementation with AHCC significantly enhanced cisplatin-induced antitumor effect in both the size (p<0.05) and weight (p<0.05). Food intake in the cisplatin-treated mice were decreased following commencement of treatment and this remained low compared with the cisplatin-untreated group (control) throughout the experiment period. Supplementation with AHCC increased the food intake in the cisplatin-treated mice. The blood urea nitrogen and serum creatinine concentrations, and the ratio of blood urea nitrogen to serum creatinine were significantly increased in the cisplatin alone treated group compared to the control group. Their increased levels were mitigated by supplementation with AHCC (100 mg/kg body weight) in the cisplatin-treated group. AHCC was also able to modulate the suppression of bone marrow due to cisplatin and the improvement was statistically significant. The histopathological examination of the kidney revealed the presence of cisplatin-induced damage and this was modulated by AHCC treatment. The potential for AHCC to ameliorate the cisplatin-evoked toxicity as well as the chemotherapeutic effect could have beneficial economic implications for patients undergoing chemotherapy with cisplatin.


Assuntos
Cisplatino/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Polissacarídeos/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Nitrogênio da Ureia Sanguínea , Células da Medula Óssea/efeitos dos fármacos , Doenças da Medula Óssea/induzido quimicamente , Doenças da Medula Óssea/prevenção & controle , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/toxicidade , Creatinina/sangue , Suplementos Nutricionais , Progressão da Doença , Sinergismo Farmacológico , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Neoplasias Experimentais/patologia , Polissacarídeos/administração & dosagem , Polissacarídeos/química , Carga Tumoral/efeitos dos fármacos
3.
J Agric Food Chem ; 55(4): 1525-31, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17253719

RESUMO

Controlled acid-catalyzed degradation of proanthocyanidin polymers in grape seeds together with L-cysteine led to oligomeric proanthocyanidin-L-cysteine complexes along with monomeric flavan-3-ol derivatives being isolated, and their structures were confirmed on the basis of spectroscopic data and by chemical means. In addition, comparative studies on the antioxidative and survival effects of oligomeric proanthocyanidin-L-cysteine complexes and proanthocyanidin polymers were performed. The oligomeric proanthocyanidin-L-cysteine complexes showed higher bioavailability and antioxidant capacity and enhanced survival time in the animal test groups. In addition, it is suggested that the oligomeric complexes may help to prevent oxidative stress and may reduce free radical production.


Assuntos
Antioxidantes/farmacologia , Cisteína/química , Cisteína/farmacologia , Polímeros/química , Proantocianidinas/química , Proantocianidinas/farmacologia , Animais , Flavonoides/farmacologia , Masculino , Camundongos , Fenóis/farmacologia , Polímeros/farmacologia , Polifenóis , Ratos , Ratos Wistar
4.
Food Chem Toxicol ; 45(3): 378-87, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17081671

RESUMO

Oligonol((R)) is an optimised phenolic product containing catechin-type monomers and lower oligomers of proanthocyanidin that emanate from a technology process which converts polyphenol polymers into oligomers. In a single dose toxicity study administration of Oligonol (2000mg/kg bw) by gavage for 4 weeks was found to be safe with no side effects (such as abnormal behavior and alopecia). Body weight gain and food consumption were within normal range. Oligonol had no observed toxicity at the dose (1/25 of LD(50)) administered for 6 months. This suggests that Oligonol is safe at repeated human intakes of Oligonol in doses lower than 200mg/day. The highest dose used in this study is equal to 12g daily for an adult man with 60kg body weight. The LD(50) was calculated to be 5.0g/kg body weight (95% confidence limit: 3.5-6.4g/kg). Studies conducted on 30 healthy volunteers consuming Oligonol at doses of 100mg/day and 200mg/day for 92 days showed good bioavailability. The biochemical parameters attesting to liver and kidney functions as well as the hematological parameters were within the normal ranges. The potential of Oligonol to induce gene mutation (a reverse mutation test) was tested using Salmonella typhimurium TA98, TA100, TA104, TA1535, TA153 and Escherichia coli WP2uvrA. Oligonol was not mutagenic to the tester strains. The lack of toxicity supports the potential use of Oligonol as a food or dietary supplement and for use as an additive in pharmaceutical and cosmetological applications.


Assuntos
Catequina/análogos & derivados , Suplementos Nutricionais/toxicidade , Fenóis/toxicidade , Administração Oral , Adulto , Animais , Comportamento Animal/efeitos dos fármacos , Catequina/administração & dosagem , Catequina/toxicidade , Qualidade de Produtos para o Consumidor , Escherichia coli/efeitos dos fármacos , Humanos , Intubação Gastrointestinal , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos , Pessoa de Meia-Idade , Modelos Animais , Testes de Mutagenicidade , Fenóis/administração & dosagem , Salmonella typhimurium/efeitos dos fármacos , Testes de Toxicidade Aguda
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