999 resultados para Cytochrome-p-450 System


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fructus Schisandrae sinensis Baill, a traditional Chinese medicine, used as tonic and sedative, has been shown at the beginning of 70's to lower the elevated serum glutamic-pyruvic transaminase (SGPT) levels of patients suffering from chronic viral hepatitis. Durign past 20 years, a series of neolignans have been isolated and identified as effective principles. Pharmacological studies revealed that they increased liver protein and glicogen synthesis, antagonized liver injuries from CCl4 and thioacetamide. The mechanism of SGPT lowering was considered as a hepato-protective and membrane stabilize action, although inhibition of the activity of liver GPT may also be existed. It was found that some principles of Schisandrae have an inducing effect on hepatic microsomal drug-metabolizing enzynme system P-450, thus explained their anti-toxic, anti-carcinogenic and anti-mutagenic effects. A synthetic derivative compound of Schisandrin called DDB has most of the above mentioned actions now used widely in Chine as a hepato-protective drug with high effectiveness in normalizing liver functions and very low side effects. From Schisandrin to synthesized DDB, pointed out a successful way in the development of new drugs from natural products.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The change in cellular reducing potential, most likely reflecting an oxidative burst, was investigated in arachidonic acid- (AA) stimulated leukocytes. The cells studied included the human leukemia cell lines HL-60 (undifferentiated and differentiated into macrophage-like and polymorphonuclear-like cells), Jurkat and Raji, and thymocytes and macrophages from rat primary cultures. The oxidative burst was assessed by nitroblue tetrazolium reduction. AA increased the oxidative burst until an optimum AA concentration was reached and the burst decreased thereafter. In the leukemia cell lines, optimum concentration ranged from 200 to 400 µM (up to 16-fold), whereas in rat cells it varied from 10 to 20 µM. Initial rates of superoxide generation were high, decreasing steadily and ceasing about 2 h post-treatment. The continuous presence of AA was not needed to stimulate superoxide generation. It seems that the NADPH oxidase system participates in AA-stimulated superoxide production in these cells since the oxidative burst was stimulated by NADPH and inhibited by N-ethylmaleimide, diphenyleneiodonium and superoxide dismutase. Some of the effects of AA on the oxidative burst may be due to its detergent action. There apparently was no contribution of other superoxide-generating systems such as xanthine-xanthine oxidase, cytochromes P-450 and mitochondrial electron transport chain, as assessed by the use of inhibitors. Eicosanoids and nitric oxide also do not seem to interfere with the AA-stimulated oxidative burst since there was no systematic effect of cyclooxygenase, lipoxygenase or nitric oxide synthase inhibitors, but lipid peroxides may play a role, as indicated by the inhibition of nitroblue tetrazolium reduction promoted by tocopherol.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The P-found protein folding and unfolding simulation repository is designed to allow scientists to perform data mining and other analyses across large, distributed simulation data sets. There are two storage components in P-found: a primary repository of simulation data that is used to populate the second component, and a data warehouse that contains important molecular properties. These properties may be used for data mining studies. Here we demonstrate how grid technologies can support multiple, distributed P-found installations. In particular, we look at two aspects: firstly, how grid data management technologies can be used to access the distributed data warehouses; and secondly, how the grid can be used to transfer analysis programs to the primary repositories — this is an important and challenging aspect of P-found, due to the large data volumes involved and the desire of scientists to maintain control of their own data. The grid technologies we are developing with the P-found system will allow new large data sets of protein folding simulations to be accessed and analysed in novel ways, with significant potential for enabling scientific discovery.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We discuss the possibility of implementing a universal quantum XOR gate by using two coupled quantum dots subject to external magnetic fields that are parallel and slightly different. We consider this system in two different field configurations. In the first case, parallel external fields with the intensity difference at each spin being proportional to the time-dependent interaction between the spins. A general exact solution describing this system is presented and analyzed to adjust field parameters. Then we consider parallel fields with intensity difference at each spin being constant and the interaction between the spins switching on and off adiabatically. In both cases we adjust characteristics of the external fields (their intensities and duration) in order to have the parallel pulse adequate for constructing the XOR gate. In order to provide a complete theoretical description of all the cases, we derive relations between the spin interaction, the inter-dot distance, and the external field. (C) 2008 WILEYNCH Verlag GmbH & Co. KGaA. Weinheim.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Detta examensarbete genomfördes på ABB Power Technologies AB i Ludvika. ABB vill överbrygga gapet mellan industri och informationsteknologi för att få de båda delarna att arbeta integrerat. ABB kallar detta koncept för Industrial IT (IIT). Ett krav från koncernledningen är att alla produkter ska vara certifierade enligt nivå 0, som är det första steget i IIT: s certifieringsprocess. Målet var att utföra en kravspecifikation på ett system som ska kunna leverera certifierad produktinformation enligt IIT-standard. Målet var även att, med kravspecifikationen som underlag, ge förslag på en lösning för att ABB ska kunna skapa och bifoga denna produktinformation till sina kunder.Det akademiska syftet var att beskriva hur man kan gå till väga för att certifiera produktinformationen enligt IIT nivå 0 på en produkt i ABB: s verksamhet. Syftet var även att öka förståelsen för IIT-konceptet.Genom hela arbetet har Gatemodellen använts. Denna projektstyrningsmodell är framtagen speciellt för informationssystem-projekt inom ABB och alla projekt som utförs inom ABB ska följa den. För att uppfylla målet med en utförd kravspecifikation har relevanta delar ur Directmodellen använts. För att få information om hur verksamheten fungerar och få insikt i problematiken har intervjuer genomförts som grundar sig på litteraturstudier.Vi föreslår att ett tidigare utgivet system vid namn Aspect Object Builder (AOB) används som grund i det här projektet. AOB: n har använts i liknande projekt inom ABB och fungerat bra. Det finns ingen standardkoppling mellan AOB: n och de system där produktinformationen finns eftersom det finns så många olika typer av filservrar, PDM- och ERP-system, där informationen lagras. Därför måste ett unikt gränssnitt göras för just detta projekt, som hjälper AOB: n att samla in data. Ett förslag till ett gränssnitt presenteras i uppsatsen.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

O maracujá é um fruto de ampla aceitação dada a qualidade de seu suco, sendo o maracujazeiro-amarelo o mais cultivado no Brasil. Nos últimos anos, cresceu o interesse pelo maracujazeiro doce, em função de alcançar bons preços no mercado in natura. Assim, informações técnicas por parte dos agricultores têm se intensificado. Este trabalho teve como objetivo avaliar a produção e a qualidade dos frutos desta espécie, cultivada sob poda e irrigação em diferentes sistemas de condução. O experimento foi conduzido no delineamento em faixas, contendo 12 tratamentos (plantas com e sem irrigação, com e sem poda e três sistemas de condução) e 3 repetições. Com base nos resultados obtidos, pode-se concluir: a) o sistema de condução e a poda não afetaram o tamanho dos frutos; b) o sistema de condução não afetou a massa dos frutos, porém as plantas podadas produziram frutos com maior massa; c) a poda diminuiu o número de frutos por planta e o rendimento por área, nos sistemas de condução em T normal e espaldeira vertical com um fio de arame; d) a poda não alterou o número de frutos por planta e o rendimento por área, no sistema de condução em espaldeira vertical com dois fios de arame.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The P transposable element copy numbers and the KP/full-sized P element ratios were determined in eight Brazilian strains of Drosophila melanogaster. Strains from tropical regions showed lower overall P element copy numbers than did strains from temperate regions. Variable numbers of full-sized and defective elements were detected, but the full-sized P and KP elements were the predominant classes of elements in all strains. The full-sized P and KP element ratios were calculated and compared with latitude. The northernmost and southernmost Brazilian strains showed fewer full-sized elements than KP elements per genome, and the strains from less extreme latitudes had many more full-sized P than KP elements. However, no clinal variation was observed. Strains from different localities, previously classified as having P cytotype, displayed a higher or a lower proportion of KP elements than of full-sized P elements, as well as an equal number of the two element types, showing that the same phenotype may be produced by different underlying genomic components of the P-M system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Different components of the mixed function oxidase (MFO) system and the levels of fluorescent aromatic compounds in bile (FACs) were measured in Cathorops spixii in order to assess the impact of polycyclic aromatic hydrocarbons (PAHs). Fish were sampled in an estuary (Santos/Sao Vicente) with a history of contamination by PAHs, mainly due to the presence of the industrial complex of Cubatao city and of another of low anthropogenic influence (Cananeia) on the Brazilian coast. FACs were higher in fish from the polluted site, and the PAH 5 and 6-ring metabolites were the most frequent - with 14% and 15%, respectively. Levels of the different components of the MFO system showed the same variation profile as the FACs for both estuaries. Therefore, the values found for somatic indexes and biomarkers with data of bile PAH metabolites indicate the presence of organic contaminants, especially in the area subject to the influence of the industrial complex on the Santos/Sao Vicente estuary.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In Drosophila, the chromosomal region 75C1–2 contains at least three genes, reaper (rpr), head involution defective (hid), and grim, that have important functions in the activation of programmed cell death. To better understand how cells are killed by these genes, we have utilized a well defined set of embryonic central nervous system midline cells that normally exhibit a specific pattern of glial cell death. In this study we show that both rpr and hid are expressed in dying midline cells and that the normal pattern of midline cell death requires the function of multiple genes in the 75C1–2 interval. We also utilized the P[UAS]/P[Gal4] system to target expression of rpr and hid to midline cells. Targeted expression of rpr or hid alone was not sufficient to induce ectopic midline cell death. However, expression of both rpr and hid together rapidly induced ectopic midline cell death that resulted in axon scaffold defects characteristic of mutants with abnormal midline cell development. Midline-targeted expression of the baculovirus p35 protein, a caspase inhibitor, blocked both normal and ectopic rpr- and hid-induced cell death. Taken together, our results suggest that rpr and hid are expressed together and cooperate to induce programmed cell death during development of the central nervous system midline.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Caryocar brasiliense Camb (Pequi) is a typical Brazilian Cerrado fruit tree. Its fruit is used as a vitamin source for culinary purposes and as a source of oil for the manufacture of cosmetics. C. brasiliense supercritical CO2 extracts exhibit antimicrobial activity against the bacteria Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and also possess antioxidant activity. This study was designed to evaluate the in vitro cytotoxicity and phototoxicity of the supercritical CO2 extract obtained from the leaves of this species. In vitro cytotoxicity and phototoxicity of C. brasiliense supercritical CO2 extracts were assessed using a tetrazolium-based colorimetric assay (XTT) and Neutral Red methods. We found that the C. brasiliense (Pequi) extract obtained by supercritical CO2 extraction did not present cytotoxic and phototoxic hazards. This finding suggests that the extract may be useful for the development of cosmetic and/or pharmaceutical products.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Diferentes afecções podem acometer o trato urinário inferior dos felinos, acarretando sinais clínicos inespecíficos como: hematúria, disúria, polaquiúria, estrangúria, periúria ou obstrução, caracterizando a doença do trato urinário inferior dos felinos (DTUIF). Entretanto, em até 65% dos felinos acometidos, a etiologia é indeterminada, denominada de doença idiopática do trato urinário inferior dos felinos (DTUIF idiopática), que tem se mostrado como um desafio ao clínico veterinário, uma vez que não há diagnóstico específico ou terapia efetiva. Atualmente, tem sido estudado o papel da inflamação neurogênica da bexiga urinária secundária ao estresse, como etiologia da DTUIF idiopática. Há evidências científicas de que a acupuntura restaure a homeostase, reduza o estresse e, pela estimulação neural periférica, ative mecanismos endógenos de antinocicepção, regulando a liberação de mediadores dos mecanismos da dor e do processo inflamatório, como a substância P. O objetivo desta revisão bibliográfica foi descrever como a acupuntura pode ser um recurso na terapia da DTUIF idiopática, tendo como base a modulação da inflamação neurogênica da bexiga urinária e o controle do estresse desses gatos.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Angular distributions for the (9)Be((8)Li, (9)Be) (8)Li elastic-transfer reaction have been measured with a 27-MeV (8)Li radioactive nuclear beam. Spectroscopic factors for the <(9)Be vertical bar(8)Li + p > bound system were obtained from the comparison between the experimental differential cross sections and finite-range distorted-wave Born approximation calculations made with the code FRESCO. The spectroscopic factors so obtained are compared with shell-model calculations and other experimental values. Using the present value for the spectroscopic factors, cross sections and reaction rates for the (8)Li(p,gamma) (9)Be direct proton-capture reaction of astrophysical interest were calculated in the framework of the potential model.