67 resultados para Hepatic drug metabolism
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A manufactured product (Ectoplus®) composed by a cypermethrin (44.7%) and dichlorvos (4.2%) mixture was administered (10mg/kg/day, orally, by gavage) to pregnant rats, during the periods of gestation+lactation, gestation, and lactation. Control mothers received vehicle aqueous solution during the gestation+lactation period. With the progeny, in the 1-15 post-natal days (PNDI-15) there were observed alterations in the periods of occurrence of teeth, hair, unfolding of ears, and in the developmental period for following reflexes: postural, palmar grasp, negative geotaxis, and acoustic startle reflex. After weaning (PND21), there were observed the presence of cypermethrin and dichlorvos in the blood brain and liver; decrease in weight of liver, of cholinesterase activity in the plasma, liver, and brain, and hepatic metabolizing activity of drugs; alterations of levels of gamma glutamyl transferase enzymes, of creatinine, and of potassium in the serum of the animals. In conclusion, neonatal exposure to a formulated mixture of cypermethrin and dichlorvos is inductive to alterations in characteristics that indicate somatic and neuromuscular development of the progeny, and in certain biochemical parameters. The results suggest that enzymatic assessment associated with somatic and neuromotor assessment can be important markers of developmental characteristics in neonatal toxicity by pesticide formulations based on mixtures of insecticides.
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The present study examines the effects of a hypercaloric diet on hepatic glucose metabolism of young rats, with and without monosodium glutamate (MSG) administration, and the association of these treatments with evaluating markers of oxidative stress. Male weaned Wistar rats (21 days old) from mothers fed with a hypercaloric diet or a normal diet, were divided into four groups (n=6): control (C) fed with control diet; (MSG) treated with MSG (4 mg/g) and control diet; (HD) fed with hypercaloric diet and (MSG-HD) treated with MSG and HD. Rats were sacrificed after the oral glucose tolerance test (OGTT), at 45 days of treatments. Serum was used for insulin determination. Glycogen, hexokinase(HK), glucose-6-phosphatase(G6PH), lipid hydroperoxide, superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px) were determined in liver. HD rats showed hypoglycemia, hyperinsulinemia, and high hepatic glycogen, HK and decreased G6PH. MSG and MSG-HD had hyperinsulinemia, hyperglycemia, decreased HK and increased G6PH in hepatic tissue. These animals had impaired OGTT. HD, MSG and MSG-HD groups had increased lipid hydroperoxide and decreased SOD in hepatic tissue. Hypercaloric diet and monosodium glutamate administration induced alterations in metabolic rate of glucose utilization and decreased antioxidant defenses. Therefore, the hepatic glucose metabolic shifting induced by HD intake and MSG administration were associated with oxidative stress in hepatic tissue.
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Aflatoxins (AF) and fumonisins (FU) are a major problem faced by poultry farmers, leading to huge economic losses. This experiment was conducted to determine the effects of AF (1 mg/kg of feed) and FU (25 mg/kg of feed), singly or in combination, on the lipid metabolism in commercial layers and investigate the efficacy of a commercial binder (2 kg/t of feed) on reducing the toxic effects of these mycotoxins. A total of 168 Hisex Brown layer hens, 37 wk of age, were randomized into a 3 × 2 + 1 factorial arrangement (3 diets with no binder containing AF, FU, and AF+FU; 3 diets with binder containing AF, FU, and AF+FU; and a control diet with no mycotoxins and binders), totaling 7 treatments. The hens contaminated with AF showed the characteristic effects of aflatoxicosis, such as a yellow liver, resulting from the accumulation of liver fat, lower values of plasma very low-density lipoprotein and triglycerides, and higher relative weight of the kidneys and liver. Hepatotoxic and nephrotoxic effects of FU were not observed in this study. On the other hand, the FU caused a reduction in small intestine length and an increase in abdominal fat deposition. The glucan-based binder prevented some of the deleterious effects of these mycotoxins, particularly the effects of AF on hepatic lipid metabolism, kidney relative weight, and FU in the small intestine. © 2013 Poultry Science Association Inc.
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The prodrug hydroximethylnitrofurazone (NFOH) presents antichagasic activity with greatly reduced toxicity compared to its drug matrix nitrofurazone (NF). Besides these new characteristics, the prodrug was more active against the parasite T. cruzi amastigotes. These advantages make the prodrug a possible therapeutic alternative for the treatment of both acute and the chronic phase of Chagas disease. However, the knowledge of pharmacokinetic profile is crucial to evaluate the feasibility of a new drug. In this study, our objective was to evaluate the in vivo formation of NF from the NFOH single administration and to evaluate its pharmacokinetic profile and compared it to NF administration. A bioanalytical method to determine the NF and NFOH by LCMS/MS was developed and validated to perform these investigations. Male albino rabbits (n=15) received NF intravenously and orally in doses of 6.35 and 63.5 mg / kg respectively, and NFOH, 80.5 mg / kg orally. The serial blood samples were processed and analyzed by mass spectrometry. The system operated in positive and negative modes for the analites determination, under elution of the mobile phase 50:50 water: methanol. The administration of NFOH allowed the calculation of pharmacokinetic parameters for the prodrug, and the NF obtained from NFOH administration. Using the pharmacokinetic profile obtained from the NF i.v. administration, the oral bioavailability of NF from the administered prodrug was obtained (60.1%) and, as a key parameter in a prodrug administration, should be considered in future studies. The i.v. and oral administrations of NF differ in the constant of elimination (0.04 vs 0.002) and elimination half-life (17.32 min vs 276.09 min) due to the low solubility of the drug that hinders the formation of molecular dispersions in the digestory tract. Still, there was observed no statistical differences were observed between the pharmacokinetic parameters of orally administered NF and NF obtained from NFOH. The calculated area under the curve (AUC 0-∞) showed that the exposure to the parental drug was fairly the same (844.79 vs 566.44) for NF and NF obtained from the prodrug administration. The tendency to higher NF's mean residence time (MRT) as observed in the prodrug administration (956.1 min vs 496.3 min) guarantees longer time for the action of the drug and it allows the expansion of the administration intervals. These findings, added with the beneficial characteristics of the prodrug encourage new efficacy tests towards the clinical use of NFOH.
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Agaricus blazei (Ab) has become popularly known for its medicinal properties. Scientifically, it has been tested with regard to its capacity to protect genetic material against damage. We examined different organic extracts (methanolic extract-ME, hexanic extract-HE and n-butanolic extract-BE) and an aqueous extract (AE) of Ab, for their capacity to induce DNA damage as well as for their protective effect. Genetic damage was determined by the chromosomal aberration assay (CA) in CHO-k1 cells for all extracts and the cytokinesis block micronucleus assay (CBMN) in non drug-metabolizing (CHO-k1) and drug-metabolizing (HTC) cell lines for extract BE only. The extracts did not show clastogenicity but showed anticlastogenicity. The greatest percent reduction obtained were with BE (105%) and AE (126%) treatments in CA. BE treatment did not display genotoxicity in CHO-k1, but was genotoxic in HTC. However, BE was shown to be antigenotoxic causing decreased micronucleus frequency in HTC and CHO-k1 cells. These results suggest that all the extracts contained protective substances, but in some cases they could show a genotoxic effect with regard to metabolism. Therefore, these findings warrant caution in the use of this mushroom by the population. (c) 2005 Elsevier Ltd. All rights reserved.
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Periodontal disease initiation and progression occurs as a consequence of the host immune inflammatory response to oral pathogens. The innate and acquired immune systems are critical for the proper immune response. LPS, an outer membrane constituent of periodontal pathogenic bacteria, stimulates the production of inflammatory cytokines IL-1 beta TNF alpha IL-6 and RANKL either directly or indirectly. In LPS-stimulated cells, the induction of cytokine expression requires activation of several signaling pathways including the p38 MAPK pathway. This review will discuss the significance of the p38 MAPK pathway in periodontal disease progression and the potential therapeutic consequences of pharmacological antagonism of this pathway in the treatment of periodontal diseases.
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The influence of fasting on the potential of diethylnitrosamine (DEN) to initiate liver cucinogenesis was tested in a medium-term assay using the development of putative preneoplastic altered foci of hepatocytes (AFH) as the endpoint. Male Wistar rats fasted for 48 hr were given a single ip injection of DEN (200 mg/kg body weight). Partial hepatectomies were carried out at wk 3 and the rats were killed at wk 8. Fasted rats exhibited a small increase in the numbers of AFH with glutathione S-transferase in the placental form and eosinophilic AFH when compared with non-fasted animals. However, after a 6-wk exposure to 0.05% sodium phenobarbital in the diet, there were no differences in the numbers of AFH between fasted and non-fasted animals. Fasting also increased DEN-dependent centrilobular cell necrosis and specifically drug metabolism as indicated in vivo by a decreased time of paralysis of the lower limbs induced by zoxazolamine (40 mg/kg body weight, ip) and by an unaltered sleeping time induced by sodium pentobarbital (40 mg/kg body weight, ip). The results indicate that although fasting during the initiation stage of carcinogenesis increases DEN hepatotoxicity, it does not interfere quantitatively with the development of liver preneoplastic lesions.
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In this study, we show that safranine at the concentrations usually employed as a probe of mitochondrial membrane potential significantly protects against the oxidative damage of mitochondria induced by Fe(II)citrate. The effect of safranine was illustrated by experiments showing that this dye strongly inhibits both production of thiobarbituric acid-reactive substances and membrane potential decrease when energized mitochondria were exposed to Fe(II)citrate in the presence of Ca 2+ ions. Similar results were obtained with the lipophylic compound trifluoperazine. It is proposed that, like trifluoperazine, safranine decreases the rate of lipid peroxidation due to its insertion in the membrane altering the physical state of the lipid phase.
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Trifluoperazine (TFP) (35 μM) prevents mitochondrial transmembrane potential (ΔΨ) collapse and swelling induced by 10 μM Ca2+ plus oxyradicals generated from δ-aminolevulinic acid autoxidation. In contrast with EGTA, TFP cannot restore the totally collapsed ΔΨ. So, TFP might not remove Ca2+ from its 'harmful site', but could impair the ROS-driven cross-linking between membrane -SH proteins. Our data are correlated with the protective uses of TFP against oxidative processes promoted by oxyradicals plus Ca2+.
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Diarylpropenamine derivatives are a class of compounds which have been evaluated as potential drug candidates. Here a specific and reproducible HPLC method for the determination of cis- and trans-isomers of the unsubstituted derivative, 3-(4'-bromo-[1,1'-biphenyl]-4-yl)-3-(4-X-phenyl-N,N-dimethyl-2-propen-1-amine (I, where X=H) in feces is described. The analyte I and internal standard, nitro derivative (II, where X=NO2), were isolated from the basified biological matrix using a liquid-liquid extraction with ethyl acetate followed by a solid-phase procedure performed on a silica cartridge. The organic phase was evaporated to dryness, the residue was reconstituted in mobile phase and injected into the HPLC system. The analytes were eluted with ethyl acetate-hexane-triethylamine (59:40:1) in HPLC column (silica) and detected by UV spectrophotometry at 272 nm. Linearity, precision and accuracy data for feces standards after extraction were acceptable. The method has been applied to analyses of feces samples from rats dosed with I, in which it could be anticipated that fecal excretion is quantitatively the major route for I elimination. Copyright (C) 1999 Elsevier Science B.V.
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The World Health Organization (WHO) recommends that prescriptions of medicaments must be one parameter utilized to know how the medication is used by people. To do so, one specific methodology has been indicated, that is, the selected indicators of the use the medicaments. We applied this methodology with the aim of presenting a descriptive study of the physician prescription in Pediatric Clinic of the Health Basics Units. The results obtained are: the average number of medicaments prescribed with prescription was 2.6; the percentage of the medicaments prescribed with the generic name was 32%; the percentage of the prescriptions with antibiotics was 44.6%; the percentage of the prescriptions with injections was 10.4%; the percentage of the medicaments prescribed that are part of the municipal list was 22.8%, 27.5% for the program Dose Certs of the secretary of the State of São Paulo, and 50.4% by adding by adding the two lists. The essentiality of the medicaments prescribed may be considered very low, because only 32.6% appear in the RENAME. The percentage of the medicaments really dispensed was 39.9%. The medicaments more prescribed, according to the classification of the Anatomic-Therapeutic-Chemical (ATC), were the ones which acted in Respiratory System (26.8%), followed by anti-infectives for systemic use (16.4%) and by medicaments with acted in Alimentary tract and metabolism (15.8%). The conclusion is that the prescribers are moved by commercial influence of the drug makers, first because of the low prescription of medicaments by their generic name, second by the low number of medicaments effectively dispensed and then the low concordance between the ones prescribed and the ones included in the lists patterned by Tabatinga and by the State of São Paulo.
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Objective: To review the literature on inhaled nitric oxide and to describe its main clinical applications in pediatrics. Sources of data: A 10 year literature review with selection of the most important publications on inhaled nitric oxide, using the Medline and Cochrane Systematic Review databases. Summary of the findings: This review was organized as follows: introduction; metabolism and biological effects; clinical applications; dosage, gas administration and weaning; precautions and side-effects. Inhaled nitric oxide use was described in persistent pulmonary hypertension and hypoxia of the newborn, acute respiratory distress syndrome, primary pulmonary hypertension, heart surgery, chronic obstructive pulmonary disease, sickle cell anemia, and bronchospastic disease. Conclusions: Inhaled nitric oxide is a therapeutic approach with wide clinical applications in pediatrics. Its use is safe when administered in pediatric intensive care units under strict monitoring. As a pulmonary vasodilator, nitric oxide has beneficial effects on gas exchange and ventilation. Controlled trials, focusing on early gas administration should be performed under many clinical conditions, especially acute respiratory distress syndrome.
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Pulmonary thromboembolism (PTE) ranges from incidental, clinically unimportant thromboembolism to massive embolism with sudden death. Its treatment is well established in two groups of patients: heparin for those with normal systemic blood pressure without right ventricular dysfunction (RVD) and thrombolysis for those with RVD and circulatory shock. In an intermediate group of patients with systemic blood pressure stability combined with RVD, which is usually associated with worse outcome, the treatment is controversial. There are authors who strongly suggest thrombolysis while others contraindicate this procedure and recommend anticoagulation with heparin. This is a narrative review that includes clinical trials comparing thrombolysis and heparin for the treatment of PTE patients with systemic blood pressure stability and RVD published since 1973. The results show that there are only four trials on this subject with less than 500 patients. Many PTE patients with systemic blood pressure stability and RVD might benefit from thrombolysis but, on the other hand, the risk for hemorrhagic events may be increased. Large randomized clinical trials are required to clarify this. © 2008 Bentham Science Publishers Ltd.