Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Biochim Biophys Acta ; 796(3): 232-7, 1984 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-6548932

RESUMO

4-Hydroxynonenal, which is a major product of lipid peroxidation in rat liver microsomes, was detected in native Ehrlich ascites tumor cells. Its formation was stimulated either by ferrous ions or by Fe(II)-histidinate. The identification was based on chromatographic (TLC/HPLC) and ultraviolet-spectroscopic evidence using synthetic 4-hydroxynonenal as reference. Highest values of 4-hydroxynonenal concentration (about 0.1 microM in the cell suspension) after 30 min of incubation were observed with Fe(II)-histidinate as stimulant. Saturation was already reached after an incubation period of 10 min. The results confirm the expectation by Schauenstein and Esterbauer (in Submolecular Biology and Cancer, Ciba Foundation Series 67 (1979) pp. 225-244, Excerpta Medica, Amsterdam) that endogenous lipid peroxidation gives rise to a distinct intracellular level of alpha, beta-unsaturated aldehydes. A simple hypothetical mechanism for the formation of 4-hydroxynonenal from n-6-polyunsaturated fatty acids is presented.


Assuntos
Aldeídos/análise , Carcinoma de Ehrlich/metabolismo , Peróxidos Lipídicos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Histidina/farmacologia , Ferro/farmacologia , Camundongos , Camundongos Endogâmicos , Espectrofotometria Ultravioleta
2.
Free Radic Biol Med ; 13(4): 281-8, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1398213

RESUMO

This study was performed to evaluate the hypothesis that oxygen radicals/lipid peroxidation are involved in reperfusion injury in humans. The study included 37 patients, who underwent surgical revascularization operations for kidney transplantation (9 subjects) or limb salvage (28 subjects). Peripheral venous blood samples were taken 30 min before starting reperfusion (baseline) and 1, 2, 3, 4, and occasionally 6 to 18 h after revascularization. The amount of plasma malonaldehyde formed in the reaction with thiobarbituric acid (MDA-TBA) was determined by high-performance liquid chromatography (HPLC). The baseline MDA-TBA values of the patients were very close to the value determined for 20 age-matched healthy subjects (i.e. mean +/- SD 0.689 +/- 0.294 nmol/mL plasma [range 0.2 to 1.37] vs. 0.700 +/- 0.209 nmol/mL plasma [range 0.385 to 1.29]). All patients responded to successful revascularization with significant increase of the plasma MDA-TBA within about 1 h after onset of reperfusion. Thereafter the values decreased nearly to the preoperative state. The mean increase of MDA-TBA was 107% in kidney transplantation and 54% in limb revascularization. In a few patients with severe arteriosclerosis, revascularization was not optimal and no increase in the MDA-TBA value occurred. The results of this study indicate that therapeutic intervention to prevent lipid-peroxidation-mediated reperfusion injury is confined to a rather narrow time window and must be undertaken either prior to or immediately after revascularization.


Assuntos
Isquemia/cirurgia , Peróxidos Lipídicos/sangue , Reperfusão , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Embolectomia , Extremidades/irrigação sanguínea , Extremidades/cirurgia , Feminino , Humanos , Transplante de Rim , Cinética , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Tiobarbitúricos , Trombectomia
3.
Free Radic Biol Med ; 31(11): 1368-74, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11728808

RESUMO

Does cigarette smoking increase vitamin E utilization in vivo? A trial was carried out in 6 smokers and 5 nonsmokers of comparable ages and serum lipids. Subjects consumed 75 mg each d(3)-RRR and d(6)-all rac-alpha-tocopheryl acetates (natural and synthetic vitamin E, respectively) daily for 7 d with a standardized breakfast. Fasting blood samples were drawn on days -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 14, 21 (negative days indicate supplementation). In both groups, plasma d(3)-alpha-tocopherol concentrations were approximately double of d(6)-alpha-tocopherol. At day 0, the %d(3) alpha-tocopherols (d(3)-alpha-tocopherol/total-alpha-tocopherol x 100) were similar in both smokers and nonsmokers. Subsequently, there was a trend toward a faster exponential disappearance of the plasma %d(3) alpha-tocopherol in smokers compared with nonsmokers (0.30 +/- 0.04 compared with 0.24 +/- 0.05, p =.0565). The calculated %d(3) half-lives were 55.6 +/- 7.4 h in smokers and 72.1 +/- 17.3 h in nonsmokers (p =.0630). By day 21, the %d(3) in smokers had decreased to 1.4% +/- 0.3% while it was 2.2% +/- 0.7% (p =.0418) in the nonsmokers. These data suggest that smoking increases plasma vitamin E disappearance, but further studies are needed to confirm this finding and to assess its cause.


Assuntos
Fumar/sangue , Vitamina E/farmacocinética , alfa-Tocoferol/análogos & derivados , Adulto , Colesterol/sangue , Deutério , Humanos , Cinética , Malondialdeído/sangue , Tocoferóis , Triglicerídeos/sangue , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/sangue , alfa-Tocoferol/farmacocinética
4.
Free Radic Biol Med ; 18(5): 849-59, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7797092

RESUMO

We investigated the effect of correcting beta-carotene deficiency in cystic fibrosis (CF) patients on two parameters of lipid peroxidation. The resistance to oxidation of low density lipoprotein (LDL) was measured by the lag time preceding the onset of conjugated diene formation during exposure to copper(II) ions, and lipid peroxide formation was quantitated by malondialdehyde concentrations in plasma (TBA/HPLC method). Simultaneously, alpha-tocopherol and beta-carotene concentrations were determined in LDL and in plasma. Thirty-four CF patients were investigated before and after 3 months of oral beta-carotene supplementation. Beta-carotene concentrations increased (p < 0.0001) in plasma (mean +/- SD) (0.09 +/- 0.06 vs. 1.07 +/- 0.86 mumol/l) and in LDL (0.02 +/- 0.02 vs. 0.31 +/- 0.28 mol/mol), without significant changes in alpha-tocopherol, either in plasma (24.7 +/- 5.9 vs. 25.4 +/- 7.6) or in LDL (8.47 +/- 2.95 vs. 9.05 +/- 4.13). Lag times, being shorter (p < 0.05) in patients than in controls, increased from 48.5 +/- 21.3 to 69.1 +/- 27.9 min (p < 0.001) and plasma MDA concentrations, being greater (p < 0.0001) in patients than in controls, decreased from 0.95 +/- 0.32 to 0.61 +/- 0.15 mumol/l (p < 0.0001). At 3 months, lag times and MDA concentrations did not any longer differ between patients and controls. These data suggest that excess lipid peroxidation occurring in beta-carotene deficiency can be limited and normalized during efficient beta-carotene supplementation in CF patients.


Assuntos
Carotenoides/deficiência , Carotenoides/uso terapêutico , Fibrose Cística/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/sangue , Lipoproteínas LDL/sangue , Criança , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos de Coortes , Fibrose Cística/tratamento farmacológico , Feminino , Humanos , Lipoproteínas LDL/efeitos dos fármacos , Masculino , Malondialdeído/sangue , Oxirredução , Valores de Referência , Análise de Regressão , Vitamina E/sangue , beta Caroteno
5.
Am J Clin Nutr ; 65(6): 1858-66, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9174484

RESUMO

Vitamin C status and possible associations with the disease process in cystic fibrosis (CF) patients were investigated. Plasma vitamin C concentrations in patients from two different mid-European populations (Swiss, n = 62; Austrian, n = 60) taking no or low-dose vitamin C from multivitamin supplements did not differ from each other or from control subjects (n = 34). Vitamin C concentrations decreased with age (5.05 mumol.L-1, y-1). When followed up for 12 mo, patients had the highest plasma vitamin C concentrations in February and the lowest in May and August (P < 0.01); the decrease in vitamin C was accompanied by increases in plasma malondialdehyde (P < 0.001) and tumor necrosis factor alpha concentrations (P < 0.01). During supplementation with vitamin E for 2 mo or beta-carotene for 12 mo vitamin C concentrations did not change. They correlated inversely with white blood cell count (r = -0.36, P = 0.008), bands (r = -0.36, P = 0.02), alpha 1-acid glycoprotein (r = -0.45, P = 0.002), interleukin 6 (r = -0.46, P = 0.0006), and neutrophil elastase/alpha 1-proteinase inhibitor complexes (r = -0.34, P = 0.02). In patients with vitamin C concentrations < 40 mumol/L, all indexes of inflammation were relatively high, whereas those with concentrations > 80 mumol/L (upper quartile of control subjects) showed clearly lower values. These results are consistent with the hypothesis that by scavenging oxygen free radicals vitamin C interacts with an inflammation-amplifying cycle of activation of alveolar macrophages and neutrophils, release of proinflammatory cytokines and oxygen free radicals, and inactivation of antiproteases.


Assuntos
Ácido Ascórbico/sangue , Fibrose Cística/sangue , Pneumopatias/sangue , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Fibrose Cística/etiologia , Fibrose Cística/fisiopatologia , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Inflamação/sangue , Inflamação/etiologia , Inflamação/fisiopatologia , Interleucina-6/sangue , Elastase de Leucócito/sangue , Peroxidação de Lipídeos/fisiologia , Pneumopatias/etiologia , Pneumopatias/fisiopatologia , Masculino , Malondialdeído/sangue , Estado Nutricional , Orosomucoide/análise , Orosomucoide/metabolismo , Estações do Ano , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo , Vitamina E/administração & dosagem , Vitamina E/farmacologia , beta Caroteno/administração & dosagem , beta Caroteno/sangue , beta Caroteno/farmacologia
6.
J Cancer Res Clin Oncol ; 103(3): 281-6, 1982.
Artigo em Alemão | MEDLINE | ID: mdl-6288726

RESUMO

The SH content of the soluble proteins (nanomol./mg protein) from five transplantable rat hepatomas and from the DENA-hepatoma were determined with dithionitrobenzoate (Ellman reagent). Both the total number of thiols as well as the number of SH groups that can be blocked by hydroxypentenal (HPE) increase with increasing growth rate of the tumors. In comparison with the protein thiol content of the slowest growing DENA-hepatoma (doubling time 100 days), the total protein thiols of the fastest growing Yoshida hepatoma (doubling time 2,5 days) increase by 100% and the HPE-sensitive protein thiols by 350%. The total protein thiols are significantly correlated with the growth rate (probability of error 5%), the HPE-sensitive thiols are correlated with high significance (probability of error less than 1%). These results are in accordance with the "Molecular Correlation Concept" of G. Weber and might possibly be understood as a consequence of reprogramming of gene expressions.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Proteínas de Neoplasias/análise , Neoplasias Experimentais/fisiopatologia , Compostos de Sulfidrila/análise , Animais , Carcinoma Hepatocelular/análise , Neoplasias Hepáticas , Neoplasias Experimentais/análise , Ratos , Ratos Endogâmicos BUF , Ratos Endogâmicos
7.
Kidney Int Suppl ; 78: S128-36, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11168998

RESUMO

BACKGROUND: Chronic renal failure is associated with accelerated atherosclerosis and a high incidence of cardiovascular disease. Oxidative modification of low-density lipoprotein (LDL) is considered a key event in atherogenesis. METHODS: We studied the ex vivo oxidizability of LDL exposed to Cu2+ ions (lag time, rate of propagation, maximum conjugated diene formation) and its relationship with LDL density, fatty acids, and antioxidants, along with plasma malondialdehyde (MDA) and autoantibodies against Cu2+-, MDA-, and hypochlorous acid-modified LDL and plasma antioxidants in 17 continuous ambulatory peritoneal dialysis (CAPD) patients and 21 healthy control subjects. RESULTS: LDL alpha- and gamma-tocopherol and total polyunsaturated fatty acid (PUFA) concentrations were significantly higher in the CAPD patients. LDL density was shifted to small, dense LDL. LDL oxidizability was comparable to that of healthy subjects. Lag time correlated positively with LDL alpha-tocopherol and inversely with both total PUFA concentrations and density; the rate of oxidation and LDL density correlated positively with total PUFA and total fatty acid concentrations, respectively. Ratios of autoantibody titers against oxidized to native LDL did not differ between the two groups. While plasma alpha- and gamma-tocopherol concentrations and tocopherol to cholesterol ratios were significantly higher, vitamin C concentrations were very low in the CAPD patients. MDA concentrations were 1.7 times higher than in healthy subjects. CONCLUSIONS: (1) Ex vivo LDL oxidizability is normal in CAPD patients as a result of efficient protection by LDL-associated lipophilic antioxidants, although the LDL composition is altered toward high oxidizability; and (2) the plasma antioxidant screen is insufficient due to impaired vitamin C status.


Assuntos
Peroxidação de Lipídeos , Lipoproteínas LDL/sangue , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antioxidantes/metabolismo , Autoanticorpos/sangue , Estudos de Casos e Controles , Ácidos Graxos/sangue , Ácidos Graxos Insaturados/sangue , Feminino , Humanos , Técnicas In Vitro , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Lipoproteínas LDL/imunologia , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Oxirredução , Estresse Oxidativo
8.
Free Radic Res ; 30(6): 463-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10400458

RESUMO

The purpose of our study was to evaluate the clinical impact of reperfusion injury after normothermic ischemia during major liver resections and the effect of an intraoperative antioxidant infusion. This prospective randomized study comprised 50 patients; half of them (treatment group) were given an antioxidant infusion containing tocopherol and ascorbate immediately prior to reperfusion onset. Venous blood samples for the determination of MDA-TBARS (malondialdehyde-thiobarbituric acid reactive substances) by a HPLC-based test as a marker of lipid peroxidation were taken prior to ischemia, 30 min after reperfusion onset and at the end of the operation. In the control group there was a significant increase of MDA-TBARS (p = 0.001) at 30 min after reperfusion onset. At the end of the operation the values had returned to the initial level. The treatment group showed only a marginal increase (p-value for the difference between the two groups: 0.007). After exclusion of the patients with histologically proven advanced cirrhosis the increase in the control group (p < 0.001) and the difference between the increase in the two groups (p = 0.001) became more significant. Prothrombin time was also significantly better in the treatment group (p = 0.003). Postoperative complications such as prolonged liver failure, bleeding disorders and infections were seen more often in the control group. In our study MDA-TBARS was increased after liver ischemia, but in patients with advanced cirrhosis the effect was smaller or even absent. This increase and possible clinical consequences of reperfusion injury could be reduced by intraoperative administration of an antioxidant infusion.


Assuntos
Antioxidantes/uso terapêutico , Fígado/irrigação sanguínea , Fígado/cirurgia , Traumatismo por Reperfusão/tratamento farmacológico , Antioxidantes/efeitos adversos , Ácido Ascórbico/efeitos adversos , Ácido Ascórbico/farmacologia , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Malondialdeído/sangue , Complicações Pós-Operatórias , Tempo de Protrombina , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/metabolismo , Temperatura , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Fatores de Tempo , Transaminases/metabolismo , Vitamina E/efeitos adversos , Vitamina E/farmacologia
9.
Clin Chim Acta ; 288(1-2): 21-30, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10529454

RESUMO

Extracorporeal elimination of low density lipoprotein (LDL) is frequently used in drug-resistant hypercholesterolemia. LDL-immunoapheresis selectively removes LDL and lipoprotein(a) [Lp(a)] from plasma. Lipid peroxidation is one unwanted side effect, that occurs during extracorporeal plasma treatment. The purpose of this study was to investigate the effect of LDL immunoapheresis on lipid peroxidation. Before and after a single LDL-immunoapheresis treatment, plasma concentrations of lipid hydroperoxides, determined with two different spectophotometric assays, thiobarbituric acid-reacting substances (TBARS), determined spectrophotometrically and malondialdehyde (MDA), determined by an MDA-TBA/HPLC method, were measured in 13 hypercholesterolemic patients. In addition MDA was also determined in the eluate of the apheresis column. Before treatment, plasma cholesterol and LDL cholesterol concentrations were significantly higher in patients than in healthy control subjects, as were the lipid peroxidation products. LDL-immunoapheresis treatment of the patients led to significant decreases in total cholesterol (69+/-8%), LDL-cholesterol (79+/-7%), HDL-cholesterol (35+/-17%), triglycerides (38+/-21%), apolipoprotein-B (77+/-6%), apolipoprotein-A1 (25+/-5%) and Lp(a) concentrations (76+/-10%). Changes in plasma lipid peroxide concentrations (17+/-8 nmol/l before vs. 14+/-5 nmol/l after treatment) were not significant, neither were those in TBARS (3. 0+/-2.6 micromol/l vs. 2.3+/-1.3 micromol/l) or MDA concentrations (1.03+/-0.17 micromol/l vs. 1.0+/-0.20 micromol/l). Patients with high baseline values showed a decrease, whereas others did not. MDA was present (0.57+/-0.13 micromol/l) in the eluate of the apheresis column, suggesting that, along with LDL, lipid peroxidation products are also removed. From these results we conclude that a single LDL-immunoapheresis treatment effectively reduces LDL and Lp(a) in the absence of increases in plasma lipid peroxidation products.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Peroxidação de Lipídeos , Lipoproteínas LDL/isolamento & purificação , Adulto , Estudos de Casos e Controles , Humanos , Hipercolesterolemia/sangue , Peróxidos Lipídicos/sangue , Lipoproteínas LDL/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Redox Rep ; 1(4): 247-54, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27405711

RESUMO

The purpose of the study was the assessment of the acute inflammatory response in patients (N = 12) with comparable trauma severity and uneventful wound healing courses in the postsurgical period as a contribution to the search for objectifiable criteria in the monitoring of wound healing. Whole blood chemiluminescence (CL) on the one hand and the lipid peroxidation product malondialdehyde (MDA) on the other hand as tools for the detection of the respiratory burst activity of phagocytes were used as inflammation markers and were compared with the established marker PMN elastase. Blood samples were withdrawn daily from the day of surgery to the 14th postsurgical day. CL-parameters and PMN elastase increased postoperatively reflecting surgical trauma, while MDA remained within the normal range during the whole time of observation. A decrease of CL-activity in the postsurgical period correlated with decreasing PMN elastase levels (r = 0.52, P<0.0001) as well as with the tapering of local inflammation signs concerning the wound situs. MDA values neither correlated with PMN elastase nor with any CL-parameters. The results indicate that the measurement of the phagocytic activation by CL, used for the first time in traumatology to monitor wound healing, represents a promising marker for the assessment of the actual inflammatory status.

11.
Angiology ; 49(4): 307-14, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9555934

RESUMO

Cyclosporin A (CyA) is intensively metabolized by the hepatic cytochrome p450 III monooxygenase A system in the human liver, the most important metabolites being M1, M17, and M21. Because CyA and its metabolites have nephrotoxic, hepatotoxic, and neurotoxic side effects, CyA dosage must be calculated to avoid the risk of organ rejection through underdosage and toxic organ damage through overdosage or accumulation of metabolites. In this study, we determined the whole-blood concentrations of cyclosporin and metabolite M17 by high-pressure liquid chromatography (HPLC) and by monoclonal specific and polyclonal nonspecific fluorescence polarization immunoassay (Abbott) in patients after immunosuppressive treatment. Patients with different resorption and metabolization rates showed high individual variations. CyA concentrations in patients with good liver function and low concentrations of CyA metabolites showed a good correlation between the HPLC and the FPIA (TDx-monoclonal assay) methods in ranges between 25 and 180 ng/mL. TDx-monoclonal was not always as precise as HPLC. In cases of metabolic disorders, we found false high CyA concentrations assayed with the immunologic method, caused by a crossreaction of the elevated metabolite concentration. We found that HPLC rendered more information about the extent of immunosuppressive activity and the metabolization rate and showed a good correlation with the concentration of metabolite M17 and total metabolites measured with the Abbott CyA polyclonal kit.


Assuntos
Ciclosporina/uso terapêutico , Ciclosporinas/sangue , Imunossupressores/uso terapêutico , Anticorpos , Anticorpos Monoclonais , Doenças Autoimunes/sangue , Doenças Autoimunes/tratamento farmacológico , Transplante de Medula Óssea , Cromatografia Líquida de Alta Pressão , Reações Cruzadas , Ciclosporina/administração & dosagem , Ciclosporina/efeitos adversos , Ciclosporina/metabolismo , Ciclosporinas/efeitos adversos , Sistema Enzimático do Citocromo P-450/metabolismo , Imunoensaio de Fluorescência por Polarização , Rejeição de Enxerto/prevenção & controle , Transplante de Coração , Humanos , Terapia de Imunossupressão , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Imunossupressores/metabolismo , Rim/efeitos dos fármacos , Transplante de Rim , Fígado/efeitos dos fármacos , Fígado/enzimologia , Transplante de Fígado , Taxa de Depuração Metabólica , Sistema Nervoso/efeitos dos fármacos , Fatores de Risco
13.
Talanta ; 65(3): 638-43, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18969847

RESUMO

This study aimed to develop a simple and efficient optimized high-performance liquid chromatograph (HPLC) method for simultaneous determination of cyclosporine A (CyA) and its major, partly active metabolites AM1, AM9, AM4N, and AM19 in whole blood from transplant patients using cyclosporine D (CyD) as internal standard. The method used a CN analytical column maintained at 60 degrees C with hexan-isopropanol (93:7, v/v) as mobile phase; detection was at 212nm. Linearity for all five compounds was tested in the range of 31-1500ngml(-1) for CyA and of 31-1000ngml(-1) for metabolites. The limit of detection was found to be 15ngml(-1) for all compounds. This modified, inexpensive method is also suitable for measuring cyclosporine A and metabolite concentrations in routine monitoring of patients undergoing treatment with CyA.

14.
Microsc Acta ; 85(1): 19-24, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6170867

RESUMO

The total protein and total protein-SH content of both the cytoplasmic fraction and the nuclei of Ehrlich ascites tumor cells (EATC) were determined macroscopically and microspectrometrically. The separation into cytoplasmic and nuclear fraction was performed by a modification of the method of Mamaril et al. [4]. The macroscopical determination of the total protein and the total protein-SH content were performed with the Folin method of Lowry et al. [2] and the DTNB method of Ellman [1], respectively. The quantitative microspectrometrical determinations of total protein content and of total protein-SH content were performed using the tetrazonium staining method of Nöhammer [5] and Nöhammer et al. [6] and the mercurochromcyanide (MCN) method of Nöhammer et al. [7], respectively. Within the intact cells, fixed and stained histochemically, the total protein and the total protein-SH content of the nuclei were determined microspectrometrically. The so called "nuclear extinctions", measured as the sum of the extinctions of the nucleus and of the parts of the cytoplasm above and below the nucleus, were calculated into the true nuclear extinctions, which then show a good correspondence to the values measured both microspectrometrically and macroscopically on isolated nuclei. The calculation for the true nuclear extinctions is based on a special preparation of spherically shaped cells and nuclei.


Assuntos
Carcinoma de Ehrlich/análise , Proteínas de Neoplasias/análise , Nucleoproteínas/análise , Espectrofotometria/métodos , Compostos de Sulfidrila/análise , Animais , Núcleo Celular/análise , Camundongos , Modelos Biológicos , Coloração e Rotulagem
15.
Histochemistry ; 71(2): 291-300, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6165706

RESUMO

Mercurochrom (2,7-dibromo-4-(hydroxymercuri)-fluoresceine-disodium salt) reacts histochemically not only with protein-SH-groups, but is also bound unspecifically to cellular proteins. The amount of the unspecifically staining approximately equals the specific SH-staining. Two methods are described to remove the unspecifically bound Mercurochrom, without influencing the specific reaction with the protein thiols. The first applies 0,1 m thioglycolate pH 4.0 (MT4-method), the other a special tris-cyanide-buffer pH 7.4 (MCN)-method). Aliquots from preparations of rat hepatocytes, Yoshida ascites tumor cells, Ehrlich ascites tumor cells, isolated nuclei of Ehrlich-cells and chicken thymocytes were investigated as well for the protein thiol content of the cells macroscopically with DTNB as microspectrophotometrically for the extinctions of the cells after staining with MT4- or MCN-method. A strong correlation was found between the macroscopically determined total-protein-SH-contents and the microphotometrically determined mean-total-extinctions of the cells. Additionally the molar absorptivities determined macroscopically by Schauenstein and Scheuringer (1980) coincide excellently with the values found microspectrometrically on MT4- and MCN-stained cells.


Assuntos
Fluoresceínas , Histocitoquímica , Merbromina , Proteínas/análise , Compostos de Sulfidrila/análise , Animais , Carcinoma de Ehrlich/análise , Galinhas , Fígado/análise , Camundongos , Proteínas de Neoplasias/análise , Ratos , Sarcoma de Yoshida/análise , Espectrofotometria , Linfócitos T/análise
16.
World J Surg ; 19(5): 738-44, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7571673

RESUMO

The objective of this study was to evaluate the antioxidative properties of the multivitamin cocktail Omnibionta (alpha-tocopherol, ascorbic acid, retinol, vitamin B complex) in terms of diminishing lipid peroxidation with improvement of leg edema performance after limb revascularization operations in humans. Fifty-one subjects were selected; the control group contained 27 patients and the treatment group 24 patients, who received the vitamin cocktail intravenously before the start of reperfusion. All patients suffered from acute or chronic arterial occlusive disease, except two subjects with arterial trauma. MDA-TBARS in plasma, quantified by HPLC, taken as a measure of lipid peroxidation was significantly increased (p < 0.001) in the control group 1 hour after reperfusion onset and decreased to its baseline value within the following 2 hours (0.73 +/- 0.26, 1.21 +/- 0.48, 0.99 +/- 0.48, 0.73 +/- 0.33 nmol/ml). In contrast, in the treatment group MDA-TBARS did not exceed the baseline value during the reperfusion period (0.93 +/- 0.30, 0.70 +/- 0.29, 0.65 +/- 0.23, 0.70 +/- 0.37 nmol/ml). Leg edema, expressed by extremity circumference, was significantly (p < 0.008) elevated in the control group (30.7 +/- 4.04 cm versus 35.35 +/- 4.12 cm) compared to a lack of increase in the treatment group (29.25 +/- 5.13 cm versus 29.76 +/- 5.70 cm). These results suggest that antioxidative vitamin treatment might be valuable in preventing lipid peroxidation and decreasing extremity edema.


Assuntos
Antioxidantes/administração & dosagem , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Peroxidação de Lipídeos/efeitos dos fármacos , Linfedema/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Resultado do Tratamento
17.
Clin Physiol ; 21(6): 718-22, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11722480

RESUMO

The nicotinamide adenine dinucleotide (NADH)/nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system is a major source of superoxide anion (.O2-) production in the human vasculature and may therefore influence lipid peroxidation and severity of atherosclerosis. This study aimed to investigate a hypothetical influence of the p22 phox C242T polymorphism on the generation of malondialdehyde (MDA), extent and clinical onset of coronary artery disease (CAD) in patients. We studied 108 male Caucasians with angiographically documented CAD and 45 controls free of vascular disease under 60 years of age. p22 phox C242T genotypes and MDA levels were determined. Additional information was obtained from each subject on classic risk factors and clinical events of CAD. Genotype distribution in CAD-patients and controls was thymine-thymine (TT): 13.8% (13.3%), cytosine-thymine (CT): 46.3% (53.3%) and cytosine-cytosine (CC): 39.8% (33.3%), respectively. No significant influence was seen of the p22 phox C242T polymorphism on corresponding mean MDA levels in both groups. Furthermore, age at onset of first time angina pectoris (AP) and myocardial infarction (MCI) was not significantly different between genotype groups. It is concluded that the C242T polymorphism of the p22 phox gene is not associated with lipid peroxidation as measured by MDA, and is not a genetic risk marker for CAD Caucasians.


Assuntos
Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Peroxidação de Lipídeos/fisiologia , Proteínas de Membrana Transportadoras , NADH NADPH Oxirredutases/genética , NADPH Desidrogenase/genética , NADPH Oxidases/genética , Fosfoproteínas/genética , Polimorfismo Genético , Adulto , Idade de Início , Angina Pectoris/fisiopatologia , Angiografia , Genótipo , Humanos , Masculino , Malondialdeído/análise , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , NAD/genética , NAD/metabolismo , NADH NADPH Oxirredutases/metabolismo , NADPH Oxidases/metabolismo , Polimorfismo de Fragmento de Restrição , Fatores de Risco
18.
Z Naturforsch C Biosci ; 36(7-8): 572-8, 1981.
Artigo em Alemão | MEDLINE | ID: mdl-7281898

RESUMO

When incubated for 30 min in vitro, 4-hydroxyalkenals in a 5 x 10-3 M solution react with SH-groups of soluble cytoplasmic and nuclear proteins (ProtL-SH) of Morris hepatomas 9618 A and 5123 tc, and of Ehrlich ascites tumor (EAT) cells. The extent of the reaction strongly increases with decreasing doubling time of the respective tumors. Former experiments with EAT cells have shown that the reaction with cytoplasmic ProtL-SH causes inhibition of respiration, glycolysis, and probably of other SH-controlled processes associated with cell division. The intranuclear reaction leads to an inhibition of DNA- and RNA-synthesis. In a 2 x 10-4 M solution of hydroxyalkenals, however, the reaction with cytoplasmic ProtL-SH diminishes almost completely so that no measurable inhibition of respiration and only 3% inhibition of glycolysis are observed, while 20 to 30 percent of the nuclear ProtL-SH are still blocked. This corresponds well with a previous observation that a 2 x 10-4 M solution of hydroxypentenal inhibits DNA-synthesis by 90 percent.


Assuntos
Aldeídos/farmacologia , Carcinoma de Ehrlich/fisiopatologia , Neoplasias Hepáticas Experimentais/fisiopatologia , Animais , Divisão Celular/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Camundongos , Consumo de Oxigênio/efeitos dos fármacos , RNA Neoplásico/biossíntese , Ratos , Relação Estrutura-Atividade
19.
Perfusion ; 9(4): 277-83, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7981465

RESUMO

Production of oxygen free radicals and subsequent lipid peroxidation are thought to occur during cardiopulmonary bypass (CPB) and myocardial ischaemia-reperfusion injury. Malondialdehyde (MDA), a lipid peroxidation product, was measured simultaneously in arterial and coronary sinus blood before CPB and after release of the aortic crossclamp. Additional arterial samples were drawn pre-, per-, and postoperatively. Thirteen patients scheduled for coronary artery and/or valvular surgery were studied. Cold, crystalloid, cardioplegic arrest (54 [35-120] minutes, median [range]) was induced retrogradely. Preoperatively, arterial MDA was 0.78 +/- 0.4 (mean +/- SD) mumol/l, and increased during CPB (highest level 3.66 +/- 1.08 mumol/l, p < 0.002, 30 minutes after the start of reperfusion). Arterial MDA was still increased four hours after the end of CPB (3.17 +/- 0.88 mumol/l, p < 0.003), but had returned to normal the first postoperative day. No difference was found between arterial and coronary sinus samples at any time. In conclusion, MDA increased in arterial blood during CPB, indicating that lipid peroxidation occurred. There was no intracoronary release of MDA during reperfusion of the ischaemic heart.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Peróxidos Lipídicos/metabolismo , Idoso , Aorta , Artérias , Constrição , Vasos Coronários , Humanos , Malondialdeído/sangue , Pessoa de Meia-Idade , Reperfusão Miocárdica
20.
Eur J Orthop Surg Traumatol ; 5(1): 21-6, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24193268

RESUMO

In the search for objective methods to monitor the course of wound healing, the proteinase PMN elastase (n=56 pat.), the lipid peroxidation product malondialdehyde (MDA) (n=18 pat.), and polymorphonuclear neutrophil granulocytes (PMN) migratory behaviour were measured [1, 6, 7, 11]. This "stimulated PMN-locomotion" was quantified by a new PMN migration filter assay (n=10 pat.) [2]. We determined the clinical course during "per primam (pp)" wound healing (group 1), "pp" wound healing with secondary inflammatory disease (group 2), manifestation of a bacterial wound infection during healing-"per secundam (ps)" (group 3) and manifest wound infection ("ps") at the time of admission (group 4).In group 1 PMN elastase returned to normal values on the 10th postsurgical day. Median values in group 3 reflected a highly significant difference (p<0,01) on day 4 and 5 compared with group 1. In group 2 and 4 medians reflected consistent high values without reaching normal ranges throughout. MDA did not exceed the normal range in group 1, in group 3 low levels persisted, and in group 4 a recurring increase was noticed.The total migration index median (TMI) in Group I, which quantifies the percentage of stimulated PMN, reflected its highest value immediately post-surgically and dropped to the lowest on the 13th postsurgical day (decrease by 54%). The mean invasion depth (T/2), a parameter of PMN distribution, showed only slight variation with time. In a group 3-patient, T/2 reflected a maximal migratory stimulation on day 6, 4 days before clinical infection signs could be noticed; then it dropped to the lowest on day 10. This decrease probably reflects a PMN behavioural change from migration to phagocytosis [9].

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA