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1.
J Anim Sci ; 93(4): 1573-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26020179

RESUMO

Several concerns have been raised over the health of animals used in equestrian games that have their origins in historical or religious events and are currently held in many countries. This study investigated physiological stress response and health status of horses participating in the Sartiglia, a historical horse tournament held in the city of Oristano, Italy, which is principally based on the attempts of masked horsemen at a gallop to run a sword through a hole in a suspended silver star. Blood samples were collected from 21 horses the day before the tournament (D0), during the tournament (D1), and the day after the tournament (D2). Samples were analyzed for complete blood count and biochemical, hormonal, and oxidative stress assays. Data were analyzed using the mixed effect model with sampling session as one of the fixed effects. On the whole, blood parameters evidenced an optimal health status of horses at D0. Significant dehydration and increase of circulating glucose, enzymes, cortisol, and ß-endorphin were registered at D1 (P < 0.001) with a complete recovery of physiological values just at D2. The reactive oxygen metabolites (d-ROM), from which the prooxidant activity can be evaluated, showed an increase from D0 to D1 and D2. Concentration of biological antioxidant potential, which measured the antioxidant capacity, was characterized by the maximum level registered during the tournament and counteracted the simultaneous increase of d-ROM. It can be hypothesized that the tournament played an important role in causing high levels of oxidant markers not only because of the physical exercise represented by the gallop but also because the emotional stressors. In conclusion, the tournament caused significant changes of most parameters, which rapidly recovered to baseline values within the day after. These data will certainly be useful for a future implementation of tests in equine medicine and for the improvements of knowledge of changes of blood parameters and health of horses in similar tournaments.


Assuntos
Antioxidantes/metabolismo , Cavalos/sangue , Hidrocortisona/sangue , Espécies Reativas de Oxigênio/sangue , Esportes , beta-Endorfina/sangue , Bem-Estar do Animal , Animais , Biomarcadores/sangue , Contagem de Células Sanguíneas , Feminino , Nível de Saúde , Cavalos/fisiologia , Itália , Masculino , Estresse Oxidativo/fisiologia , Estresse Fisiológico/fisiologia
2.
Bioresour Technol ; 183: 221-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25742754

RESUMO

Activated hydrochars obtained from the hydrothermal carbonization of orange peels (Citrus sinensis) followed by various thermochemical processing were assessed as adsorbents for emerging contaminants in water. Thermal activation under flows of CO2 or air as well as chemical activation with phosphoric acid were applied to the hydrochars. Their characteristics were analyzed and related to their ability to uptake three pharmaceuticals (diclofenac sodium, salicylic acid and flurbiprofen) considered as emerging contaminants. The hydrothermal carbonization and subsequent activations promoted substantial chemical transformations which affected the surface properties of the activated hydrochars; they exhibited specific surface areas ranging from 300 to ∼620 m(2)/g. Morphological characterization showed the development of coral-like microspheres dominating the surface of most hydrochars. Their ability to adsorb the three pharmaceuticals selected was found largely dependent on whether the molecules were ionized or in their neutral form and on the porosity developed by the new adsorbents.


Assuntos
Carvão Vegetal/química , Citrus/química , Resíduos , Poluentes Químicos da Água/isolamento & purificação , Água/química , Adsorção , Diclofenaco/isolamento & purificação , Cinética , Modelos Teóricos , Nitrogênio/química , Compostos Orgânicos , Ácido Salicílico/química , Temperatura
3.
J Colloid Interface Sci ; 440: 102-8, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25460695

RESUMO

Activated carbons from two species of pine cones (Pinus canariensis and Cupressus sempervirens) were prepared by phosphoric acid activation and tested for the removal of nitrate ions from aqueous solution. To investigate the feasibility of improving their nitrate adsorption capacity, two different post-treatments­a thermal treatment and a treatment with saturated urea solution­were also applied to the prepared activated carbons. Comparison of the treated and untreated activated carbons showed that both post-treatments improved the nitrate adsorption performance more than twice. The maximum adsorption capacity, as evaluated from determination of the adsorption isotherms for the P. canariensis based carbons, and their proper representation by the Langmuir model, demonstrated that the post-treatment with the urea solution led to activated carbons with increased nitrate removal effectiveness, even superior to other reported results. Enhancements in their adsorption capacity could be mainly ascribed to higher contents of nitrogen and basic functional groups, whereas porous structure of the activated carbons did not seem to play a key role in the nitrate uptake.


Assuntos
Carbono/metabolismo , Nitratos/metabolismo , Pinus/metabolismo , Adsorção
4.
J Dairy Sci ; 98(2): 1157-66, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25497793

RESUMO

This study aimed to evaluate the effects of the dietary inclusion of grape seed, alone or in combination with linseed, on milk production traits, immune response, and liver and kidney metabolic activity of lactating ewes. Twenty-four Sarda dairy ewes were randomly assigned to 4 dietary treatments consisting of a control diet (CON), a diet containing 300 g/d per head of grape seed (GS), a diet containing 220 g/d per head of extruded linseed (LIN), and a diet containing a mix of 300 g/d per head of grape seed and 220 g/d per head of extruded linseed (MIX). The study lasted 10 wk, with 2 wk of adaptation period and 8 wk of experimental period. Milk yield was measured and samples were collected weekly and analyzed for fat, protein, casein, lactose, pH, milk urea nitrogen, and somatic cell count. Blood samples were collected every 2 wk by jugular vein puncture and analyzed for hematological parameters, for albumin, alkaline phosphatase, bilirubin, creatinine, gamma glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, protein, blood urea nitrogen, and for anti-albumin IgG, IL-6, and lymphocyte T-helper (CD4(+)) and lymphocyte T-cytotoxic (CD8(+)) cells. On d 0, 45, and 60 of the trial, lymphocyte response to phytohemagglutinin was determined in vivo on each animal by measuring skin-fold thickness (SFT) at the site of phytohemagglutinin injection. Humoral response to chicken egg albumin was stimulated by a subcutaneous injection with albumin. Dietary treatments did not affect milk yield and composition. Milk urea nitrogen and lactose were affected by diet × period. Diets did not influence hematological, kidney, and liver parameters, except for blood urea nitrogen, which decreased in LIN and increased in MIX compared with CON and GS. Dietary treatments did not alter CD4(+), CD8(+), and CD4(+)-to-CD8(+) ratio. The SFT was reduced in GS and MIX and increased in LIN compared with CON. The IgG and IL-6 were affected by diet × period. The reduction in IgG on d 60 and SFT in ewes fed GS suggests an immunomodulatory effect of this residue. The limited variation in milk and hematological and metabolic parameters suggests that GS and LIN can be included, alone or in combination, in the diet of dairy ewes without adverse effects on milk production and health status.


Assuntos
Dieta/veterinária , Linho , Lactação/fisiologia , Sementes , Ovinos/fisiologia , Vitis , Ração Animal/análise , Animais , Antioxidantes/análise , Contagem de Células , Gorduras/análise , Feminino , Concentração de Íons de Hidrogênio , Imunidade , Rim/metabolismo , Lactose/análise , Fígado/metabolismo , Leite/química , Leite/citologia , Proteínas do Leite/análise , Ovinos/imunologia , Ureia/análise
6.
Animal ; 7(9): 1464-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23676703

RESUMO

This study assessed the effects of dietary supplementation with extruded linseed on milk yield and composition, milk fatty acid (FA) profile and renal and hepatic metabolism of grazing goats in mid-lactation. Forty Saanen goats were divided into two isoproductive groups: one group was fed the control diet (CON) composed of hay and pelleted concentrate and the other group was supplemented with additional 180 g/day of extruded linseed (LIN; dry matter basis), which supplied 70 g/day of fat per head for 9 weeks. Animals grazed on pasture for ∼3 h/day after the first of the 2 daily milkings. Milk samples were collected weekly and analyzed for fat, protein, lactose, milk urea nitrogen (MUN) and somatic cell count. Blood samples were collected every 2 weeks and analyzed for total bilirubin, creatinine, aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyl transpeptidase, alkaline phosphatase, total protein and urea nitrogen. Milk yield was higher in the LIN than in the CON group (2369 v. 2052 g/day). LIN group had higher milk fat (37.7 v. 33.4 g/kg) and protein (30.7 v. 29.1 g/kg) concentration and lower MUN (35.0 v. 43.3 mg/dl) than CON group. Goats fed LIN had greater proportions of 18:1 trans11, 18:2 cis9trans11 and total polyunsatured fatty acids n-3 in milk fat, because of higher 18:3n-3 and 20:5n-3 FA, and lower proportions of short- and medium-chain FAs than goats fed CON. All kidney and liver function biomarkers in serum did not differ between dietary groups, except for AST and ALT, which tended to differ. Extruded linseed supplementation to grazing mid-lactating goats for 2 months can enhance the milk performance and nutritional profile of milk lipids, without altering the general hepatic and renal metabolism.


Assuntos
Ração Animal/análise , Biomarcadores/análise , Indústria de Laticínios/métodos , Linho/química , Cabras/fisiologia , Lactação/fisiologia , Leite/química , Análise de Variância , Animais , Biomarcadores/sangue , Análise Química do Sangue/veterinária , Suplementos Nutricionais , Ácidos Graxos/análise , Feminino , Cabras/metabolismo , Itália , Rim/metabolismo , Fígado/metabolismo , Leite/efeitos dos fármacos
7.
Bioresour Technol ; 106: 55-62, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22197337

RESUMO

A simple alkaline pre-treatment of Cupressus sempervirens cone chips was performed to improve their biosorption capacity towards methylene blue and rhodamine B from aqueous solutions, in batch and continuous modes. Biosorption kinetics were determined from single and binary dyes solutions, and properly described by the pseudo-second-order rate model. Experimental single-dye equilibrium isotherms fitted the Langmuir-Freundlich model, with maximum biosorption capacities of 0.68mmol/g for methylene blue and 0.50mmol/g for rhodamine B. Single-dye dynamic biosorption showed that breakthrough time for methylene blue biosorption was almost four times longer than for rhodamine B and that the alkaline modification of the chips greatly improved the biosorption performance. Competitive dynamic biosorption demonstrated the preference of the modified cone chips for biosorbing methylene blue, confirmed by the exit concentration overshoots obtained in the breakthrough curves of rhodamine B.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Corantes/isolamento & purificação , Cupressus/química , Hidróxidos/farmacologia , Compostos de Potássio/farmacologia , Resíduos/análise , Poluentes Químicos da Água/isolamento & purificação , Adsorção/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Cupressus/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Cinética , Azul de Metileno/isolamento & purificação , Modelos Químicos , Rodaminas/isolamento & purificação , Soluções , Temperatura
8.
Pharmacogenomics J ; 11(6): 412-28, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20548326

RESUMO

Nonsteroidal anti-inflammatory drugs possess antiproliferative activities that can affect cancer cells. The aim of this study was to examine the antiproliferative effects of ibuprofen on the MKN-45 cell line. Cells were treated with ibuprofen for 24, 48 or 72 h, and cell proliferation was evaluated by cell counting and [(3)H]-thymidine incorporation. Using microarray technology, we studied changes in the gene expression profiles over time after ibuprofen treatment. Ibuprofen induced a dose- and time-dependent reduction in cell number without altering cell viability. Genes involved in the 'biological oxidation' and 'G(1)/S checkpoint' pathways were the most significantly represented at 24 h, whereas genes involved in the 'cell cycle' and 'DNA replication' pathways were represented at 48 and 72 h. Genes associated with the 'apoptosis' pathway were also significantly represented at 72 h. Modulation of the expression of p53 and p53-induced genes (CDKN1A/p21 and GADD45), which are involved in the G(1)/S transition, suggested an effect of ibuprofen on cell-cycle progression. Using flow cytometry, we observed an early block in the G(1) phase of the cell cycle after ibuprofen treatment. In addition, P450 family transcripts were upregulated and intracellular reactive oxygen species (ROS) was increased following 12 h of ibuprofen treatment. Ibuprofen induced ROS, which resulted in cellular alterations that promoted a p53-dependent G(1) blockade. These findings suggest that ibuprofen exerts its antiproliferative actions through cell-cycle control and the induction of apoptosis. Both of these mechanisms appear to be independent of ibuprofen's anti-inflammatory effects.


Assuntos
Adenocarcinoma/genética , Anti-Inflamatórios não Esteroides/farmacologia , Perfilação da Expressão Gênica , Ibuprofeno/farmacologia , Neoplasias Gástricas/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/genética , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
9.
Bioresour Technol ; 101(24): 9500-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20727738

RESUMO

The feasibility of using cypress cone chips from Cupressus sempervirens as a low-cost biosorbent for the removal of two representative basic dyes, methylene blue (MB) and rhodamine B (RhB), from aqueous solutions was investigated in batch and continuous modes. Dyes biosorption was strongly dependent on the solution's pH. Sorption kinetics was determined and properly described by the pseudo-second-order rate model. Experimental equilibrium isotherms fitted the Langmuir model, showing maximum biosorption capacities of 0.62 mmol/g for MB and 0.24 mmol/g for RhB. Competitive experiments from a binary solution of the dyes demonstrated the preference of the cone chips for biosorbing MB. Very low desorption efficiencies were obtained for both dyes. Dynamic experiments showed that the breakthrough time was three times higher for MB biosorption than for RhB for the same conditions. Breakthrough curves were properly represented by a mathematical model.


Assuntos
Corantes/isolamento & purificação , Cupressus/anatomia & histologia , Cupressus/metabolismo , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/isolamento & purificação , Modelos Químicos , Rodaminas/isolamento & purificação , Soluções , Temperatura
10.
J Hazard Mater ; 177(1-3): 175-82, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20042290

RESUMO

Activated carbon cloths (ACC) were prepared from lyocell, a novel regenerated cellulose nanofibre fabric, by phosphoric acid activation in inert atmosphere at two different final thermal treatment temperatures (864 and 963 degrees C). Benzene, toluene and n-hexane isotherms at 298 and 273K were measured in order to gain insight into the porous structure of the ACC and to evaluate their performance for the removal of volatile organic compounds (VOCs). The Dubinin-Radushkevich equation was employed to evaluate textural parameters of the ACC. The textural characteristics of the ACC were compared with those previously determined from nitrogen (77K) and carbon dioxide (273K) adsorption data. The samples were essentially microporous. The textural parameters calculated from the hydrocarbon isotherms were in good agreement with those evaluated from nitrogen isotherms for the ACC with the wider microporosity. Additionally, the Freundlich model provided a good description of the experimental isotherms for the three volatile organic compounds. The ACC obtained at the higher temperature exhibited a larger adsorption capacity. The ACC were also electrically conductive and showed potential for regeneration by the Joule effect, as determined from macroscopic electrical measurements before and after n-hexane adsorption.


Assuntos
Celulose/química , Carvão Vegetal/química , Compostos Orgânicos Voláteis/isolamento & purificação , Adsorção , Poluentes Atmosféricos/isolamento & purificação , Conservação dos Recursos Naturais , Temperatura
11.
Vet Pathol ; 46(3): 453-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19176505

RESUMO

Malignant mixed Müllerian tumor (MMMT) is a rare neoplasm of the female genital tract. We report a case of bilateral ovarian MMMT in a 10-year-old female dog. Ovaries were only moderately enlarged with a papillary surface and firm nodules. Multiple metastases were observed in the abdominal cavity and pulmonary parenchyma. Histologically, both ovaries had intermingled carcinomatous and sarcomatous components with cartilage and bone. Metastatic lesions were not mixed. The peritoneal metastases were carcinomatous; pulmonary metastases were sarcomatous. Carcinomatous elements of the MMMT were immunohistochemically positive for cytokeratin (CK) AE1/AE3, CK7, and vimentin and estrogen receptors. Conversely, the sarcomatous cells were positive for vimentin, but negative for CKs. Chondrocytes also expressed S-100 protein. On the basis of similarities to human ovarian MMMT, the diagnosis was heterologous malignant mixed Müllerian tumor of the ovary.


Assuntos
Doenças do Cão/patologia , Tumor Mulleriano Misto/veterinária , Neoplasias Ovarianas/veterinária , Animais , Carcinossarcoma/patologia , Carcinossarcoma/veterinária , Cães , Feminino , Tumor Mulleriano Misto/patologia , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/veterinária
12.
Bioresour Technol ; 100(3): 1130-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18809320

RESUMO

An industrial raw Kraft lignin was investigated to ascertain its potential use for removal of trace Ni(II) ion from wastewater by using dilute solutions (0.34-1.7 mM) as models. The effect of demineralisation on its metal sorption ability was examined by employing acid pre-treated samples. Under fixed pre-established equilibrium conditions, the raw lignin exhibited a lower effectiveness than the demineralised one, with the latter attaining an almost complete removal of Ni(II) ions. For both lignins, sorption kinetics was properly described by a pseudo-second order rate model. Equilibrium isotherms were also determined and adequately represented by conventional two-parameter models. The higher nickel sorption capacity for the demineralised lignin compared to the raw sample was consistent with enhancements in the negative magnitude of zeta potential, sodium sorption capacity, and content of phenolic hydroxyl groups occasioned by the acid pre-treatment. Accordingly, demineralisation appears as a readily convenient strategy to improve the behaviour of industrial Kraft lignin for potential use as a biosorbent of trace nickel from polluted water.


Assuntos
Lignina/química , Minerais/química , Modelos Químicos , Níquel/química , Níquel/isolamento & purificação , Ultrafiltração/métodos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Absorção , Simulação por Computador , Estudos de Viabilidade , Poluentes Químicos da Água/química
13.
Eur J Pharm Biopharm ; 70(1): 171-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18583115

RESUMO

The formation of a novel interpolyelectrolyte complex (IPEC) between basic butylated methacrylate copolymer and kappa-carrageenan was investigated and the product formed was characterized. Turbidity measurements and elemental analyses pointed to a 1:1 interaction of the repeating units. These results and FT-IR confirmed IPEC formation. Electronic microscopy images, particle size determination by image analysis and N(2) (77K) adsorption measurements were consistent with a porous material. This IPEC formed presented very good flowability and compactibility. Two maxima were observed in the swelling behaviour as a function of pH. The performance of the IPEC as a matrix for controlled release of drugs was evaluated, using ibuprofen as a model drug. Release profiles were properly represented by a mathematical model, which indicates that the system releases ibuprofen in a zero-order manner. These profiles could be controlled by conveniently modifying the proportion of the IPEC in the tablets.


Assuntos
Anti-Inflamatórios não Esteroides/química , Carragenina/síntese química , Portadores de Fármacos , Ibuprofeno/química , Ácidos Polimetacrílicos/síntese química , Química Farmacêutica , Preparações de Ação Retardada , Composição de Medicamentos , Concentração de Íons de Hidrogênio , Cinética , Modelos Químicos , Tamanho da Partícula , Porosidade , Solubilidade , Propriedades de Superfície , Comprimidos , Tecnologia Farmacêutica/métodos
14.
Diabetes Res Clin Pract ; 72(3): 284-91, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16564105

RESUMO

OBJECTIVE: In PROPAT we implemented an integrated approach to diabetes care designed to improve the quality and reduce the cost of care. STUDY DESIGN AND METHODS: PROPAT was a case-control study matching patients by age and gender (diabetes:control ratio 1:2) within IOMA, a public employment-based health maintenance organization (HMO) of the Province of Buenos Aires, Argentina. Costs were evaluated using prevalence data from an HMO perspective. We currently report clinical and biochemical data and costs from the first 297 patients enrolled who completed 1 year in PROPAT, and compare them with those derived from control patients. RESULTS: All recommended practices recorded as care provided at baseline increased significantly 1 year after implementing PROPAT, with a parallel significant improvement in several clinical and biochemical parameters, and markedly lower total annual per capita costs. CONCLUSIONS: These results demonstrate that the implementation of a comprehensive diabetes care program can simultaneously improve quality while reducing costs.


Assuntos
Diabetes Mellitus/economia , Desenvolvimento de Programas , Qualidade da Assistência à Saúde , Adulto , Idoso , Argentina/epidemiologia , Automonitorização da Glicemia/estatística & dados numéricos , Índice de Massa Corporal , Estudos de Casos e Controles , Controle de Custos/métodos , Efeitos Psicossociais da Doença , Custos e Análise de Custo/estatística & dados numéricos , Atenção à Saúde/economia , Atenção à Saúde/organização & administração , Complicações do Diabetes/epidemiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Feminino , Hemoglobinas Glicadas/análise , Custos de Cuidados de Saúde/estatística & dados numéricos , Sistemas Pré-Pagos de Saúde/economia , Sistemas Pré-Pagos de Saúde/organização & administração , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Serviços Preventivos de Saúde/economia , Serviços Preventivos de Saúde/organização & administração , Atenção Primária à Saúde/estatística & dados numéricos , Desenvolvimento de Programas/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos
15.
Cell Death Differ ; 12(6): 603-13, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15846373

RESUMO

Recent studies suggest a close relationship between cell metabolism and apoptosis. We have evaluated changes in lipid metabolism on permeabilized hepatocytes treated with truncated Bid (tBid) in the presence of caspase inhibitors and exogenous cytochrome c. The measurement of beta-oxidation flux by labeled palmitate demonstrates that tBid inhibits beta-oxidation, thereby resulting in the accumulation of palmitoyl-coenzyme A (CoA) and depletion of acetyl-carnitine and acylcarnitines, which is pathognomonic for inhibition of carnitine palmitoyltransferase-1 (CPT-1). We also show that tBid decreases CPT-1 activity by a mechanism independent of both malonyl-CoA, the key inhibitory molecule of CPT-1, and Bak and/or Bax, but dependent on cardiolipin decrease. Overexpression of Bcl-2, which is able to interact with CPT-1, counteracts the effects exerted by tBid on beta-oxidation. The unexpected role of tBid in the regulation of lipid beta-oxidation suggests a model in which tBid-induced metabolic decline leads to the accumulation of toxic lipid metabolites such as palmitoyl-CoA, which might become participants in the apoptotic pathway.


Assuntos
Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Proteínas de Transporte/farmacologia , Ácidos Graxos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Cardiolipinas/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Proteínas de Transporte/metabolismo , Inibidores de Caspase , Caspases/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Células Cultivadas , Citocromos c/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Malonil Coenzima A/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Proteínas de Membrana/genética , Mitocôndrias Hepáticas/genética , Oxirredução/efeitos dos fármacos , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2
16.
Cloning Stem Cells ; 6(1): 15-23, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15107242

RESUMO

This work was undertaken in order to examine M-phase promoting factor (MPF) and mitogen-activated protein kinases (MAPK) activities during meiotic progression of cat oocytes cultured in two different media for two different incubation times and preovulatory cat oocytes that reached MII in vivo. Oocytes recovered from ovaries of ovariectomized cats were cultured either in TCM 199 or SOF for 24 h and 40 h. In vivo matured oocytes were recovered by follicular aspiration from ovaries of domestic cats ovariectomized 24 h to 26 h after hormonal treatment. Results showed that the kinetic of MPF and MAPK activity was similar during meiotic progression of cat oocytes matured in TCM 199 and SOF. After 24 h of incubation, MII oocytes had significantly (p < 0.001) higher MPF and MAPK levels than MII oocytes cultured for 40 h in both culture media. MPF and MAPK activity was significantly (p < 0.01) lower in the oocytes matured in vitro than in those matured in vivo. This study provides evidence that the two different maturation media did not determine differences in MPF and MAPK fluctuations and levels during meiotic progression of cat oocytes and that the time of maturation influenced the level of the two kinases. Moreover, it shows that MPF and MPK activity is higher in in vivo matured oocytes than in in vitro matured oocytes, suggesting a possible incomplete cytoplasmic maturation after culture.


Assuntos
Fator Promotor de Maturação/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oócitos/metabolismo , Animais , Gatos , Núcleo Celular/metabolismo , Feminino , Técnicas In Vitro , Cinética , Meiose , Oócitos/citologia
18.
Bioresour Technol ; 83(2): 95-104, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12056497

RESUMO

Canes from Arundo donax, a herbaceous rapid-growing plant, were used as precursor for activated carbon preparation by phosphoric acid activation under a self-generated atmosphere. The influence of the carbonization temperature in the range 400-550 degrees C and of the weight ratio phosphoric acid to precursor (R = 1.5-2.5) on the developed porous structure of the resulting carbons was studied for 1 h of carbonization time. Surface properties of the activated carbons were dependent on a combined effect of the conditions employed. Carbons developed either with R = 1.5 over the range 400-500 degrees C, or with R = 2 at 500 degrees C exhibited surface areas of around 1100 m2/g, the latter conditions promoting a larger pore volume and enhanced mesoporous character. For both ratios, temperature above 500 degrees C led to reduction in porosity development. A similar effect was found for the highest ratio (R = 2.5) and 500 degrees C. The influence of carrying out the carbonization either for times shorter than 1 h or under flowing N2 was also examined at selected conditions (R = 2, 500 degrees C). Shorter times induced increase in the surface area (approximately 1300 m2/g), yielding carbons with smaller mean pore radius. Activated carbons obtained under flowing N2 possessed predominant microporous structures and larger ash contents than the samples derived in the self-generated atmosphere.


Assuntos
Compostos Inorgânicos de Carbono/análise , Ácidos Fosfóricos/química , Poaceae/química , Adsorção , Biotecnologia/métodos , Carbono/química , Compostos Inorgânicos de Carbono/química , Cinética , Microscopia Eletrônica de Varredura , Nitrogênio/química , Oxigênio , Pressão , Temperatura , Fatores de Tempo
19.
Eur J Cancer ; 38(8): 1141-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12008204

RESUMO

Oxaliplatin (L-OHP), a diaminocyclohexane platinum derivative, is an active and well tolerated anticancer drug which is presently used in the treatment of gastrointestinal tumours. Since the efficacy of L-OHP in the treatment of multiple myeloma (MM) has not yet been evaluated, we studied the antiproliferative activity of this compound in vitro in a panel of MM cell lines (XG1, XG1a, U266 and IM-9). We found that L-OHP inhibited the growth of MM cells at therapeutically achievable concentrations (IC(50): 5-10 microM after 24 h of exposure) and was more active than Cisplatin (CDDP) or Carboplatin (CBDCA). The activity of L-OHP was apparently not affected by interleukin-6 (IL-6), the major growth and survival factor of MM cells. We also found that L-OHP induced apoptotic cell death. We demonstrated that the combination of L-OHP with Dexamethasone (Dex) resulted in the enhancement of the anti-myeloma effects. L-OHP and Dex both induced poly adenosine diphosphate (ADP)-ribose polymerase (PARP) cleavage and this induction was enhanced by the combined treatment. L-OHP-induced apoptosis correlated with caspase-3 cleavage, but this correlation could not be demonstrated in Dex-treated cells. Taken together, these in vitro results provide a rationale for the experimental use of L-OHP in the treatment of MM patients and suggest therapeutic combinations of potential value.


Assuntos
Antineoplásicos/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3 , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Dexametasona/administração & dosagem , Relação Dose-Resposta a Droga , Interações Medicamentosas , Citometria de Fluxo , Humanos , Interleucina-6/farmacologia , Mieloma Múltiplo/enzimologia , Mieloma Múltiplo/patologia , Oxaliplatina , Poli(ADP-Ribose) Polimerases/metabolismo , Células Tumorais Cultivadas
20.
Bioresour Technol ; 76(1): 15-22, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11315805

RESUMO

Changes in chemical and surface characteristics of Brazil Nut shells (Bertholletia excelsa) due to pyrolysis at different temperatures (350 degrees C, 600 degrees C, 850 degrees C) were examined. For this purpose, proximate and ultimate analyses, physical adsorption measurements of N2 (-196 degrees C) and CO, (25 degrees C) as well as samples visualisation by scanning electronic microscopy (SEM) were performed. Appreciable differences in the residue characteristics, depending markedly on the pyrolysis temperature, were observed. Release of volatile matter led to the development of pores of different sizes. Progressive increases in micropore development with increasing pyrolysis temperature took place, whereas a maximum development of larger pores occurred at 600 degrees C. Furthermore, kinetics measurements of Brazil Nut shells pyrolysis from ambient temperature up to 900 degrees C were performed by non-isothermal thermogravimetric analysis. A model taking into account the significant changes in the residue during pyrolysis, through an increase in the activation energy with temperature and solid conversion, were found to properly fit the kinetics data over the wide range of degradation investigated.


Assuntos
Nozes/química , Temperatura , Cinética , Microscopia Eletrônica de Varredura , Nitrogênio/química , Nozes/ultraestrutura
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