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1.
Cell Mol Biol (Noisy-le-grand) ; 51 Suppl: OL809-17, 2005 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-16375817

RESUMO

Deoxynivalenol (DON) and nivalenol (NIV) are toxic Fusarium secondary trichothecene metabolites that often co-occur regularly in cereal grains. These compounds were compared for their toxicity towards C57BL/6 mice on several parameters including alteration in plasma biochemistry, immune system reactivity and hepatic drug metabolism capacity. Mice received individual or combined oral doses of each toxin: 0.071 or 0.355 mg/kg of body weight, administrated three days a week for 4 weeks. Food consumption was altered by the single administration of 0.355 mg/kg of NIV, although no noticeable change of body and organ weights or liver protein contents was detected. NIV administration did cause also significant changes in total CO2 and uric acid concentrations in plasma. Individual toxin exposures led to increases in plasma IgA without no detectable change in the ex vivo production of cytokine by splenocytes. The liver ethoxyresorufin O-deealkylase, pentoxyresorufin O-depenthylase and glutathione S-transferase activities were increased in concert with cytochrome P4501a and P4502b subfamily expression. Administration of combinations of DON and NIV resulted in responses similar to that observed using individual doses of each toxin. However, depending on the ratio of toxin doses and biochemical parameters, some responses could be also additive (plasma IgA and hepatic DCNB conjugation) or synergistic (plasma uric acid).


Assuntos
Tricotecenos/administração & dosagem , Tricotecenos/toxicidade , Administração Oral , Animais , Camundongos , Camundongos Endogâmicos C57BL
2.
FEBS Lett ; 578(1-2): 53-7, 2004 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-15581615

RESUMO

The properties of coenzymes Q (CoQ9 and CoQ10) are closely linked to their redox state (CoQox/total CoQ) x 100. In this work, CoQ redox state was biologically validated by high performance liquid chromatography-electrochemical measurement after modulation of mitochondrial electron flow of cultured cells by molecules increasing (rotenone, carbonyl cyanide chlorophenylhydrazone) or decreasing (antimycin) CoQ oxidation. The tissue specificity of CoQ redox state and content were investigated in control and hypoxic rats. In control rats, there was a strong negative linear regression between tissular CoQ redox state and CoQ content. Hypoxia increased CoQ9 redox state and decreased CoQ9 content in a negative linear relationship in the different tissues, except the heart and lung. This result demonstrates that, under conditions of mitochondrial impairment, CoQ redox control is tissue-specific.


Assuntos
Mitocôndrias/metabolismo , Ubiquinona/metabolismo , Células 3T3 , Animais , Cromatografia Líquida de Alta Pressão , Transporte de Elétrons/fisiologia , Hipóxia/metabolismo , Masculino , Camundongos , Oxirredução , Estresse Oxidativo , Ratos , Ratos Wistar , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual , Ubiquinona/química
3.
Eur J Clin Pharmacol ; 60(4): 285-92, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15114428

RESUMO

AIMS: The awareness of muscular adverse drug reactions (ADRs) increased since the withdrawal of cerivastatin, a HMG-CoA reductase inhibitor, from the market in August 2001. Our objectives were to assess the detection and incidence of muscular ADRs in a University Hospital using biochemical laboratory data and to evaluate the underreporting rate of drug-induced muscular disorders. METHODS: A prospective study was undertaken at Toulouse University Hospital, France, for 1 week per month from November 2001 to October 2002. Patients were selected by means of a computerized process using biochemical laboratory data based on serum creatine phosphokinase (CPK) values (over twofold normal). Medical records of all selected patients were then consulted. RESULTS: During the period of the study, 2017 CPK tests were performed, among which 171 values were over twofold normal corresponding to 129 patients. Because of lack of data, 26 patients were excluded. Among these patients ( n=103), 28 cases of muscular ADRs were suspected, 22 of which were detected in outpatient departments. Four patients were totally asymptomatic and five had an increase of CPK over fivefold normal. Nine cases were classified as "serious". Withdrawal of suspected drugs were done in 16 cases with regression of ADRs in 13 cases. According to hospitalization data, the incidence of muscular ADRs was estimated as 7.2 (2.6-15.7) per 10,000 inpatients and 9.3 (5.8-14.1) per 10,000 outpatients over 12 weeks. The involved drugs were mainly: statins (46.4%), fibrates (14.3%), antiretrovirals (14.3%), angiotensin-II receptor antagonists (10.7%), immunosuppressants (7.1%) or hydroxychloroquine (7.1). Only two cases, judged as "serious", were spontaneously reported by physicians during the same period. CONCLUSION: The results of this survey underline the importance to take into account drug hypothesis in muscular injuries diagnosis.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Doenças Musculares/induzido quimicamente , Doenças Musculares/epidemiologia , Adulto , Idoso , Creatina Quinase/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculares/diagnóstico , Estudos Prospectivos , Rabdomiólise/induzido quimicamente , Rabdomiólise/diagnóstico , Rabdomiólise/epidemiologia
5.
JPEN J Parenter Enteral Nutr ; 25(2): 52-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11284470

RESUMO

BACKGROUND: Total parenteral nutrition (TPN) is used for critically ill patients undergoing surgery, after trauma, or during disease conditions that favor oxidative stress. We studied the effect of TPN on liver oxidative metabolism and antioxidant defenses in rats, and we compared the effect of soybean oil- and olive oil-based diets. METHODS: Seven-week-old rats (n = 28) were divided into four groups. Two experimental groups received a TPN solution containing soybean oil (TPN-S) or a mixture of olive/soybean oil, 80/20 (TPN-O), IV for 6 days. Orally fed animals received a solid diet including soybean oil (Oral-S) or olive/soybean oil, 80/20 (Oral-O). The following parameters were measured: DL-alpha-tocopherol, vitamin A, malondialdehyde and thiobarbituric acid reactive substances (MDA-TBARS), and total radical-trapping antioxidant parameter (TRAP) in serum; DL-alpha-tocopherol, vitamin A, glutathione (GSH), and catalase (Cat) activity in liver homogenate; fatty acids from phospholipid, cytochrome P-450 content, NADPH-cytochrome c2 reductase activity in liver microsomes; superoxide dismutase (SOD), glutathione peroxidase (Gpx), glutathione reductase (GR), glutathione transferase (GST), and glucose-6-phosphate dehydrogenase (G6PD) in liver cytosol. RESULTS: The soybean or olive oil diets modified the liver microsomal fatty acid phospholipid composition, but the unsaturation index remained unchanged. TPN specifically increased the saturation of the membrane. The cytochrome P-450 level and the NADPH-cytochrome c2 reductase, SOD, Gpx, Cat, and GST activities were unchanged by soybean oil or olive oil diet but decreased receiving TPN. CONCLUSIONS: In rats, TPN decreased the liver oxidative metabolism and enzymatic antioxidant defenses. This may be related to saturation of the liver microsomal fatty acids.


Assuntos
Antioxidantes/metabolismo , Fígado/metabolismo , Nutrição Parenteral Total , Óleos de Plantas/administração & dosagem , Óleo de Soja/administração & dosagem , Administração Oral , Animais , Lipídeos/química , Masculino , Azeite de Oliva , Oxirredução , Estresse Oxidativo , Ratos , Ratos Wistar
6.
Br J Nutr ; 83(3): 327-33, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10884721

RESUMO

The effects of dietary lipids on the fatty acid composition, activation and proliferation of lymphocytes were investigated. Weanling male Wistar rats were fed for 8 weeks on one of two low-fat diets which contained 50 g lipid/kg, or one of two high-fat diets containing 200 g lipid/kg, from either coconut oil or soyabean oil. The fatty acid composition of phospholipids from splenocyte membranes was affected by dietary lipid manipulation, and these differences influenced lymphocyte functions. Increased levels of linoleic acid in spleen lymphocytes correlated negatively with interleukin-2 receptor alpha-chain expression determined either by measuring the mean fluorescence or by the proportion of cells staining positive for CD25, and with the cell proliferation index. However, we found a positive correlation between interleukin-2 receptor alpha-chain expression determined by measuring the mean fluorescence and the cell proliferation index with the oleic acid concentration of spleen lymphocytes. Since phospholipid hydrolysis occurs early in lymphocyte activation, immunosuppressive effects induced by polyunsaturated fatty acids, described in the literature, could be due to an increase of linoleic acid or a decrease of oleic acid affecting many components of plasma-membrane-associated events involved in lymphocyte activation.


Assuntos
Gorduras na Dieta/farmacologia , Ácido Linoleico/metabolismo , Linfócitos/efeitos dos fármacos , Ácido Oleico/metabolismo , Animais , Gorduras na Dieta/administração & dosagem , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/química , Linfócitos/fisiologia , Masculino , Lipídeos de Membrana/química , Fosfolipídeos/química , Fosfolipídeos/fisiologia , Ratos , Ratos Wistar , Receptores de Interleucina-2/efeitos dos fármacos , Receptores de Interleucina-2/metabolismo
7.
Clin Nutr ; 19(1): 49-54, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10700534

RESUMO

Numerous studies suggest that immune function may be compromised by lipid emulsions rich in polyunsaturated fatty acids, especially linoleic acid. In our study, we compared the effect of a new olive oil-based lipid emulsion (ClinOleic(R)) containing 18% linoleic acid, and an emulsion based on soybean oil (Ivelip(R); 52% linoleic acid) on lymphocyte functions. Weaning Wistar rats (n= 24) were fed for 4 weeks on an oral diet that contained 12% of total energy as lipids from soybean oil. Then they received, during 6 days, a total parenteral nutrition (260 kcal/kg/d) in which 12% of total energy was brought by one of the two lipid emulsions. The fatty acid profile of spleen lymphocyte phospholipids reflected lipid intakes, with a higher content of oleic acid in ClinOleic(R) group and linoleic acid in Ivelip(R) group. A greater proportion of cells expressed the interleukin-2 receptor a-chain (CD25) after administration of ClinOleic(R) when compared to Ivelip(R) (55.43 +/- 3.47 vs 45.48 +/- 3.26%, P<< 0.05). Moreover, the CD25 expression was positively correlated with oleic acid content of spleen lymphocyte phospholipids (r= 0.500, P<< 0.018). These results show that ClinOleic(R) is able to induce, in vivo, a greater proportion of cells expressing CD25, and suggest that oleic acid could have a role in the observed effects.


Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Emulsões Gordurosas Intravenosas/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Nutrição Parenteral Total , Óleos de Plantas/farmacologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Gorduras Insaturadas na Dieta/administração & dosagem , Emulsões Gordurosas Intravenosas/administração & dosagem , Ácidos Graxos/análise , Citometria de Fluxo , Regulação da Expressão Gênica , Interleucina-2/biossíntese , Interleucina-2/genética , Subpopulações de Linfócitos , Linfócitos/química , Linfócitos/imunologia , Masculino , Azeite de Oliva , Óleos de Plantas/administração & dosagem , Ratos , Ratos Wistar , Baço/citologia
10.
J Lipid Res ; 37(12): 2492-501, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9017502

RESUMO

Perfusion feeding in rats induced a decrease in circulating retinol despite an adequate supply of vitamin A. We studied the effect of total parenteral nutrition (TPN) on the retinol specific carrier in rat, analyzing holo-RBP (bound to retinol) and apo-RBP (without retinol) in serum and in liver. Vitamin A-sufficient (A+) and -deficient (A-) rats were characterized in terms of vitamin A and RBP status and then perfused (TPN-A+ and TPN-A-) or orally pair-fed (O-A+ and O-A-) with vitamin A. In A+ rats, a decrease in serum retinol (2.6-fold) and an increase in apo-RBP was concomitant with a massive accumulation of RBP in the liver. In TPN-A rats, both circulating RBP and liver total RBP were decreased. In TPN-A+ rats, there was a decrease in circulating retinol (2.4-fold) in parallel to a decrease of serum and liver RBP protein and mRNA. We provide evidence that infused retinyl palmitate was not responsible for serum retinol and RBP decrease and that retinol depletion was not due to vitamin A deficiency. Whatever the vitamin A status, TPN may induce in rats a down-regulation of hepatic RBP synthesis, which may, at least partially, explain the alteration of retinol and RBP in serum.


Assuntos
Nutrição Parenteral , Proteínas de Ligação ao Retinol/metabolismo , Deficiência de Vitamina A/metabolismo , Vitamina A/sangue , Animais , Masculino , Ratos , Ratos Wistar
11.
J Nutr ; 126(12): 3040-5, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9001372

RESUMO

Quantitative variations of polyunsaturated fatty acids (PUFA) were studied in various tissues: red blood cells (RBC), hepatic microsomes, kidney, skeletal muscle and heart of young rats fed either a control diet (n = 7) or an essential fatty acid (EFA)-deficient diet (n = 7). After 4 wk, the EFA-[deficient rats had significantly lower proportions of (n-6) and (n-3) fatty acids in RBC, hepatic microsomes and kidney than the control group. Paradoxically, normal proportions of arachidonic acid [20:4(n-6)] and 5,8,11,14,17-eicosapentaenoic acid [20:5(n-3)] were retained in heart and skeletal muscle despite generally lower proportions of the precursors, 18:2(n-6) and 18:3(n-3). Moreover, absolute levels of 20:4(n-6) and 20:5(n-3) in skeletal muscle of the EFA deficient group were significantly higher than in controls and 22:5(n-3) and 22:6(n-3) levels were comparable. This suggests that fatty acid proportions alone, without any consideration of long-chain polyunsaturated fatty acid quantities, may not reflect the (n-6) and (n-3) PUFA status of individual tissues. This study indicates that diet-[induced changes in the PUFA composition of RBC, which are often used in clinical investigations, do not fully reflect the changes in the fatty acid composition of organs, and that individual tissues respond differently to EFA deficiency. The conservation of proportional and absolute levels of 20:5(n-3) and 20:4(n-6), and the decrease in the more unsaturated homologues in the heart, suggest that this organ may avidly retain 20:5(n-3) and 20:4(n-6) in order to maintain eicosanoid production.


Assuntos
Dieta , Ácidos Graxos Essenciais/deficiência , Ácidos Graxos Insaturados/sangue , Rim/metabolismo , Microssomos Hepáticos/metabolismo , Miocárdio/metabolismo , Animais , Ácidos Graxos Essenciais/administração & dosagem , Masculino , Fosfolipídeos/análise , Ratos , Ratos Wistar
12.
Eur J Endocrinol ; 135(3): 328-34, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8890724

RESUMO

The aim of this study was to determine those hormonal alterations in the gonadotropin-ovarian axis that are related to eating behavior in oligomenorrheic patients. We studied 74 oligomenorrheic women aged 26.2 +/- 0.8 years, divided into group IA (N = 13) with eating disorders, group IB (N = 61) without eating disorders and 18 normally cycling controls aged 29.2 +/- 1.6 years (group II). No subject had ovarian failure, pituitary disease, thyroid dysfunction or was taking any drug. Blood samples were taken on days 3-6 after the last menses. Luteinizing hormone (LH) was measured in two plasma pools, each made up of three samples taken at 30-min intervals, starting at 15.00 h (LH-15h) and 09.00 h (LH-9h), which allowed the mean LH (mLH) and variability in LH (V-LH: percentage increase from the lower to the higher of the two LH values) to be calculated. Follicle-stimulating hormone (FSH), sex steroids, and gonadotropin-releasing hormone-stimulated LH (sLH) and -FSH (sFSH) were also evaluated. Eating behavior was evaluated with the EAT questionnaire; the EAT 26 score, the dieting score (DS) and bulimia score (BS) were calculated. Dietary intake was evaluated in 35 group IB patients based on food diaries analyzed with the REGAL program, to evaluate daily calorie intake (Cal) and calories provided by carbohydrates (Carb), lipids (Lip) and proteins (Prot). Comparisons between groups were done by analysis of variance (followed by the Fisher PLSD test) and the Kruskal-Wallis test. Groups IA, IB and II did not differ regarding age, body mass index, LH-9h, LH-15h, mLH, FSH, sLH, sFSH, estradiol or dehydroepiandrosterone sulfate; group IA had a higher V-LH than group II (p < 0.02) and a higher testosterone level than groups IB and II (p < 0.05). Positive correlations were found between V-LH and DS (p < 0.01) and BS (p < 0.05), and between testosterone and BS (p < 0.02) and DS (p < 0.05). The V-LH was negatively correlated with Cal and Carb, and testosterone was positively correlated with Cal and Lip. In patients referred for oligomenorrhea, it is concluded that testosterone levels and variability of LH levels are related to eating behavior.


Assuntos
Comportamento Alimentar/fisiologia , Hormônios/sangue , Oligomenorreia/sangue , Adulto , Índice de Massa Corporal , Dieta , Ingestão de Energia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Transtornos da Alimentação e da Ingestão de Alimentos/patologia , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Feminino , Humanos , Hormônio Luteinizante/sangue , Oligomenorreia/etiologia , Testosterona/sangue
13.
Arch Mal Coeur Vaiss ; 87(12): 1691-8, 1994 Dec.
Artigo em Francês | MEDLINE | ID: mdl-7786109

RESUMO

The isoforms of creatinine kinase (CK) and myoglobin were analysed by serial samplings in 45 patients admitted consecutively for myocardial infarction treated by thrombolysis according to the usual indications. Angiographic controls were carried out systematically in the first 24 hours, including 20 cases at the end of thrombolysis. The patients were divided into two groups according to the patency of the infarct related artery: Group I (n = 35) with a patent vessel and Group II (n = 10) with an occluded vessel; 4 patients in Group II were successfully revascularised by angioplasty. The total CK had a higher peak value in Group II (2,393 +/- 1,991 UI/l at 547 +/- 247 min versus 2,888 +/- 2,189 IU/l at 584 +/- 395 min) but the difference was not statistically significant. The analysis of CK isoforms showed the MM3/MM1 ratio to be higher at the 2nd hour in Group I (3.74 +/- 2.37 versus 3.09 +/- 1.43) with a faster increase, without attaining statistical significance. A fourth CK MM fraction was observed at the 2nd hour in 71% of patients in Group I compared with only 20% of patients in Group II. Analysis of myoglobin showed a significantly earlier peak value in Group I (1,218 +/- 1,117 micrograms/l at 133 +/- 62 min versus 1,309 +/- 1,549 micrograms/l at 210 +/- 84 min). The sensitivity and specificity of these different markers were respectively 40%, 86%, 77%, and 60%, 70% and 67% for the CK (peak before 8 hours), the MM3/MM1 ratio (increase of over 35% in the first hour) and myoglobin (peak before 2 hours).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Creatina Quinase/análise , Infarto do Miocárdio/enzimologia , Mioglobina/análise , Angiocardiografia , Feminino , Humanos , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Revascularização Miocárdica , Terapia Trombolítica
14.
Arch Mal Coeur Vaiss ; 87(10): 1289-96, 1994 Oct.
Artigo em Francês | MEDLINE | ID: mdl-7771873

RESUMO

Many enzyme systems such as glutathione peroxidase (GPx) or superoxide dismutase (SOD) neutralise the oxygen derived free radicals produced during myocardial reperfusion by thrombolysis. Erythrocytic SOD, plasma and erythrocytic GPx and their cofactor selenium, substances reacting with thiobarbituric acid (TBARS) were analysed by repeated sampling between T0 and 48 hours in 24 patients treated by thrombolysis for acute myocardial infarction. Angiographic control was undertaken systematically between 60 and 180 minutes after initiating thrombolytic therapy: 18 patients had a patent vessel and 6 patients had an occluded vessel recanalised in 5 cases by angioplasty. Biological analysis was performed in the 23 patients successfully revascularised by thrombolysis, eventually completed by angioplasty. The plasma GPx decreased non-significantly between T0 and 2 hours from 246.8 +/- 53.3 to 233 +/- 39 U/ml with a significant increase between 2 and 48 hours from 233 +/- 39.2 to 294 +/- 76 U/ml, whereas the erythrocytic GPx rose significantly and constantly between T0 and 48 hours from 34.8 +/- 7.1 to 37.6 +/- 7.5 U/gHb with significant consumption of selenium between T0 and 4 hours from 81.2 +/- 14 to 68.5 +/- 12.6 micrograms/l. The erythrocytic SOD increased significantly between T0 and 48 hours from 318.9 +/- 40.8 to 337 +/- 59 U/gHb. Finally, the analysis of plasma TBARS showed a non-significant rise between T0 and 30 minutes from 1.59 +/- 0.30 to 1.71 +/- 1.43 mm/l with a return to the basic line values after about 2 hours. These results show a significant increase in the activity of enzymes protecting against the liberation of oxygen free radicals, such as erythrocyte or plasma GPx and erythrocyte SOD between T0 and 48 hours with consumption of selenium, cofactor of GPx, and an increase in circulating lipid peroxydes in acute myocardial infarction treated by thrombolysis. They also illustrate the oxidative stress which occurs in this situation.


Assuntos
Fibrinolíticos/uso terapêutico , Glutationa Peroxidase/sangue , Malondialdeído/sangue , Infarto do Miocárdio/metabolismo , Oxigênio/metabolismo , Superóxido Dismutase/sangue , Adulto , Idoso , Eritrócitos/enzimologia , Feminino , Radicais Livres , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/tratamento farmacológico , Selênio/sangue , Terapia Trombolítica/métodos
15.
J Vet Pharmacol Ther ; 17(4): 271-4, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7966545

RESUMO

An acute non-immune inflammation model was used to compare the action of two non-steroidal anti-inflammatory drugs, flunixin meglumine and tolfenamic acid, on prostaglandin E2 (PGE2) synthesis in bovine inflammatory exudate. The tissue cage model used involves subcutaneous implantation of polypropylene cages and subsequent stimulation by carrageenan injection of the granulation tissue which develops within the cage. Twelve calves were randomly assigned to three groups receiving placebo, flunixin meglumine and tolfenamic acid, respectively. Inflammatory exudate was sampled 30 min after carrageenan injection and at seven subsequent time points. PGE2 levels were determined by radioimmunoassay. At each time point post-carrageenan injection, flunixin meglumine inhibited PGE2 synthesis to a greater extent than tolfenamic acid. At 4, 8, 12 and 24 h these differences were statistically significant.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Clonixina/análogos & derivados , Dinoprostona/biossíntese , Exsudatos e Transudatos/imunologia , Inflamação/imunologia , ortoaminobenzoatos/farmacologia , Animais , Carragenina , Bovinos , Clonixina/farmacologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Masculino , Distribuição Aleatória
16.
Free Radic Res ; 20(4): 205-18, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8205223

RESUMO

In our search to establish a reference .OH production system with respect to which the reactivity of copper(II) complexes could then be tested, the influence of free Cu2+ ions on the Cu+/H2O2 reaction has been investigated. This influence depends on the CCu2+/CCu+ ratio. At low Cu2+ concentrations, .OH damage to various detector molecules decreases with increasing Cu2+ concentrations until CCu2+/CCu+ reaches unity. Above this value, .OH damage increases sharply until CCu2+/CCu+ becomes equal to 5 with salicylate and 2 with deoxyribose, ratios for which the protective effect of Cu2+ cancels. Finally, at higher concentrations, Cu2+ ions logically add their own .OH production to that normally expected from Cu+ ions. The possible origin of this unprecedented alternate effect has been discussed. The possible influence of Cu+ ions on the generation of .OH radicals by water gamma radiolysis has also been tested and, as already established for Cu2+ in a previous work, shown to be nonexistent. This definitely confirms that either form of ionised copper cannot scavenge .OH radicals in the absence of a ligand.


Assuntos
Cobre , DNA/química , Radical Hidroxila , Ferro , Cátions Bivalentes , Óxidos N-Cíclicos , Desoxirribose/química , Espectroscopia de Ressonância de Spin Eletrônica , Raios gama , Hidroxilação , Cinética , Salicilatos , Ácido Salicílico , Marcadores de Spin
17.
Free Radic Res Commun ; 15(6): 305-17, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1314758

RESUMO

Prior to comparative studies on the reactivity of various copper complexes with respect to OH. radicals, the influence of free Cu2+ ions on the superoxide-independent generation of OH. radicals through Fenton assays and water gamma radiolysis has been tested in the present work. Cu2+ ions have been shown to behave in a distinct manner towards each of these two production systems. As was logically expected from the noninvolvement of copper in OH. radical production through gamma radiolysis, no influence of Cu2+ ions has been observed on the amount of radicals detected in that case. In contrast, Cu2+ ions do influence OH. radical generation through iron-driven Fenton reactions, but differently depending on copper concentration. When present in high concentrations, Cu2+ ions significantly contribute to OH. radical production, which confirms previous observations on the reactivity of these in the presence of hydrogen peroxide. At lower levels corresponding to copper/iron ratios below unity on the contrary, Cu2+ ions behave as inhibitors of the OH. production in a pH-dependent manner over the 1-6 range investigated: the lower the pH, the greater the inhibition. The possible origin of this previously unreported inhibitory effect is discussed.


Assuntos
Cobre , Hidróxidos , Cromatografia Líquida de Alta Pressão , Óxidos N-Cíclicos , Desoxirribose , Radicais Livres , Raios gama , Concentração de Íons de Hidrogênio , Radical Hidroxila , Hidroxilação , Ferro , Ligantes , Salicilatos , Ácido Salicílico , Marcadores de Spin , Superóxidos
18.
Cah Anesthesiol ; 40(5): 343-7, 1992.
Artigo em Francês | MEDLINE | ID: mdl-1422932

RESUMO

Transurethral prostatic resection using a 1.5% glycine solution causes a well known clinical and metabolic syndrome called TURP-syndrome. Recent development of percutaneous renal surgery is responsible of several similar accidents. In a prospective study of 150 patients (mean age: 35 +/- 10) subjected to a percutaneous nephrolithotomy, the natremia and the amino acid content of the plasma were measured preoperatively and immediately postoperatively by chromatography. The study shows that there is a post-nephrolithotomy syndrome in two per cent. This syndrome contains a hemodilution with hyponatremia and reabsorption of irrigation fluid. Glycolemia, serinemia and threoninemia increase significantly. These modifications have a good correlation between them except for the natremia. Variability of results in this study and in the literature is explained by difficulty and duration of surgery, volume of glycol used, increasing intrarenal pressures and sudden opening of vessels peroperatively. The gravity of post-nephrolithotomy syndrome requires to change the irrigate solute and use normal saline solution when it is possible.


Assuntos
Glicina/sangue , Nefrostomia Percutânea , Irrigação Terapêutica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemodiluição , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Serina/sangue , Sódio/sangue , Síndrome , Treonina/sangue
19.
Clin Chim Acta ; 203(1): 57-65, 1991 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-1769121

RESUMO

Endogenous 13-cis- and all-trans-retinoic acids have been quantitated in human serum using a solvent extraction procedure followed by isocratic reversed phase high performance liquid chromatography and UV detection. In healthy adults, after an overnight fasting period, the concentrations of 13-cis- and all-trans-retinoic acids yielded 5.3 +/- 2.43 nmol/l and 11.8 +/- 3.3 nmol/l, respectively (mean +/- SD). The method has been successfully applied to the analysis of both isomers in serum from patients with idiopathic skeletal hyperostosis in whom, the 13-cis- as well as all-trans-retinoic acid levels were raised as compared to the control group.


Assuntos
Hiperostose Esquelética Difusa Idiopática/sangue , Isotretinoína/sangue , Tretinoína/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Ligação ao Retinol/análise , Espectrofotometria Ultravioleta , Vitamina A/sangue
20.
Ann Nutr Metab ; 35(1): 8-18, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2059001

RESUMO

We have recently shown the kinetic behavior of liver retinyl esters in rats with adequate vitamin A levels receiving oral vitamin supplementation. In the present work we have studied the effects of intramuscular administration of a vitamin A preparation on the metabolism of vitamin A in the rat. Retinol administered intramuscularly to rats in the form of an emulsion brought about a significant increase in the serum and liver concentration of vitamin A; this increase was slightly less than in orally treated rats. In each group, retinyl palmitate constituted 80-85% of the total retinyl esters, followed by stearate (9-13%), laurate, palmitoleate, myristate, linoleate and pentadecanoate making up 3-10%. The subcellular localization of all retinyl esters is similar and dependent on age but not on the route of administration. These results indicate that although the best hepatic storage is achieved with an orally administered vitamin A emulsion, the intramuscular administration of a physiological dose might provide an effective supplementation method if oral vitamin A is contraindicated.


Assuntos
Fígado/metabolismo , Vitamina A/administração & dosagem , Vitamina A/farmacocinética , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Ésteres/farmacocinética , Ácidos Graxos/análise , Injeções Intramusculares , Masculino , Ratos , Ratos Endogâmicos , Frações Subcelulares/metabolismo , Vitamina A/sangue
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