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1.
Eur Rev Med Pharmacol Sci ; 28(3): 1103-1110, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38375716

RESUMO

OBJECTIVE: The aim of this study was to explore the protective effect of candesartan against cisplatin-induced kidney damage, with a specific focus on the growth differentiation factor 15 (GDF-15) pathway. MATERIALS AND METHODS: 24 adult female Wistar rats, with a weight range of 200-210 grams, were enrolled in the study. Eight rats were included as a normal control group and did not receive any medication. 16 rats were administered cisplatin at a dosage of 2.5 mg/kg/day twice a week for 4 weeks (total dose 20 mg/kg). Then, they were randomly divided into two groups and treated with 1 ml/kg/day tap water or 8 mg/kg/day candesartan via oral gavage daily for 4 weeks. At the end of the treatment period, animals were sacrificed, and their kidneys were assessed histologically. In addition, plasma malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), creatinine, and GDF-15 levels were assessed. RESULTS: Treatment with candesartan resulted in a significant rise in serum GDF-15 levels and a significant reduction in levels of serum MDA, TNF-α, IL-6, and creatinine compared to the cisplatin and saline group. Candesartan treatment effectively protected the kidney injury, and histopathological examinations of the kidneys confirmed these results. CONCLUSIONS: This study demonstrates that candesartan alleviates cisplatin-induced renal toxicity by further increasing GDF-15, downregulating inflammatory markers, and reducing oxidative stress.


Assuntos
Benzimidazóis , Compostos de Bifenilo , Cisplatino , Nefropatias , Tetrazóis , Ratos , Feminino , Animais , Cisplatino/toxicidade , Fator 15 de Diferenciação de Crescimento , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Creatinina , Nefropatias/induzido quimicamente , Nefropatias/tratamento farmacológico , Nefropatias/prevenção & controle , Rim/patologia , Estresse Oxidativo
2.
AAPS PharmSciTech ; 22(1): 2, 2020 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-33222036

RESUMO

Drug nanocrystals have been used for a wide range of drug delivery platforms in the pharmaceutical industry, especially for bioavailability enhancement of poorly water-soluble drugs. Wet stirred media milling (WSMM) is the most widely used process for producing dense, stable suspensions of drug nanoparticles, also referred to as nanosuspensions. Despite a plethora of review papers on the production and applications of drug nanosuspensions, modeling of WSMM has not been thoroughly covered in any review paper before. The aim of this review paper is to briefly expose the pharmaceutical scientists and engineers to various modeling approaches, mostly mechanistic, including computational fluid dynamics (CFD), discrete element method (DEM), population balance modeling (PBM), coupled methods, the stress intensity-number model (SI-SN model), and the microhydrodynamic (MHD) model with a main focus on the MHD model for studying the WSMM process. A total of 71 studies, 30 on drugs and 41 on other materials, were reviewed. Analysis of the pharmaceutics literature reveals that WSMM modeling is largely based on empirical, statistically based modeling approaches, and mechanistic modeling could help pharmaceutical engineers develop a fundamental process understanding. After a review of the salient features and various pros-cons of each modeling approach, recent advances in microhydrodynamic modeling and process insights gained therefrom were highlighted. The SI-SN and MHD models were analyzed and critiqued objectively. Finally, the review points out potential research directions such as more mechanistic and accurate CFD-DEM-PBM simulations and the coupling of the MHD-PBM models with the CFD.


Assuntos
Composição de Medicamentos/métodos , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Tamanho da Partícula , Solubilidade , Suspensões , Água/química
3.
Biotech Histochem ; 89(4): 304-14, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24160412

RESUMO

Matrix metalloproteinases (MMPs) are enzymes that are responsible for degradation of extracellular matrix (ECM); they are involved in the pathogenesis of ischemia-re-perfusion (I-R) injury. We investigated the possible preventive effect of alpha-lipoic acid (LA) in a renal I-R injury model in rats by assessing its reducing effect on the expression and activation of MMP-2 and MMP-9 induced by I-R. Rats were assigned to four groups: control, sham-operated, I-R (saline, i.p.) and I-R+ LA (100 mg/kg, i.p.). After a right nephrectomy, I-R was induced by clamping the left renal pedicle for 1 h, followed by 6 h re-perfusion. In the sham group, a right nephrectomy was performed and left renal pedicles were dissected without clamping and the entire left kidney was excised after 6 h. LA pretreatment was started 30 min prior to induction of ischemia. Injury to tubules was evaluated using light and electron microscopy. The expressions of MMP-2 and MMP-9 were determined by immunohistochemistry and their activities were analyzed by gelatin zymography. Serum creatinine was measured using a quantitative kit based on the Jaffe colorimetric technique. Malondialdehyde (MDA) and glutathione (GSH) were analyzed using high performance liquid chromatography. Tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-1 were assessed using enzyme-linked immunosorbent assay (ELISA). I-R caused tubular dilatation and brush border loss. LA decreased both renal dysfunction and abnormal levels of MDA and GSH during I-R. Moreover, LA decreased significantly both MMP-2 and MMP-9 expressions and activations during I-R. TIMP-1 and TIMP-2 levels were increased significantly by LA administration. LA modulated increased MMP-2 and MMP-9 activities and decreased TIMP-1 and TIMP-2 levels during renal I-R.


Assuntos
Rim/efeitos dos fármacos , Rim/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/prevenção & controle , Ácido Tióctico/administração & dosagem , Animais , Antioxidantes/administração & dosagem , Ativação Enzimática/efeitos dos fármacos , Rim/irrigação sanguínea , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Distribuição Tecidual/efeitos dos fármacos , Resultado do Tratamento
4.
Clin. transl. oncol. (Print) ; 11(4): 243-249, abr. 2009. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-123609

RESUMO

INTRODUCTION: Peroxisome proliferator-activated receptor gamma (PPAR-gamma) and retinoic acid receptors (RAR/RXR) belong to the nuclear steroid receptor family. In vitro studies have suggested that PPAR-gamma ligands are highly effective in preventing mammary tumours and these effects are enhanced by some retinoids. However, in vivo anti-initiator and anti-promoter efficacies of this combination are not clear. AIM AND METHODS: The present study aimed to investigate the chemopreventive efficacies of the PPAR-gamma ligand rosiglitazone (200 microg/kg/day), synthetic retinoid fenretinide (0.3 mg/kg/day) and their combination on a DMBA-induced rat mammary carcinogenesis model. RESULTS: In the rosiglitazone group, no malignant tumour developed, apart from the lowest proliferative mammary lesions. In the fenretinide group, 30% developed a malignant tumour but there were no benign tumours. Cancer incidences were 61.5% and 10% in the control and combination groups respectively. CONCLUSIONS: Our results showed that the PPAR-gamma ligand rosiglitazone and synthetic retinoid fenretinide have potent chemopreventive properties against in vivo mammary carcinogenesis; however, the efficacies were not enhanced by their combination (AU)


Assuntos
Animais , Feminino , Ratos , Antineoplásicos/uso terapêutico , Fenretinida/uso terapêutico , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/prevenção & controle , Tiazolidinedionas/uso terapêutico , Carcinógenos/toxicidade , Quimioterapia Combinada , Estradiol/sangue , Neoplasias Mamárias Experimentais/induzido quimicamente , Prolactina/metabolismo , Ratos Sprague-Dawley , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática
5.
Med Oncol ; 25(4): 471-3, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18392956

RESUMO

A pilot study was performed for setting up the Dokuz Eylül University Breast Tumor DNA Bank (DEUBTB) to facilitate the sharing of tumor DNA/RNA samples and related data from cases collected by collaborators specializing in the breast cancer diseases between 2004 and 2006. The pilot study aimed to provide answers for certain questions on: (1) ethical concerns (informing the volunteer for donating specimen, anonymizing the sample information, procedure on sample request), (2) obtaining and processing samples (technical issues, flowchart), (3) storing samples and their products (storing forms and conditions), (4) clinical database (which clinical data to store), (5) management organization (quality and quantity of personnel, flowchart for management relations), (6) financial issues (establishment and maintenance costs). When the bank had 64 samples, even though it is quite ready to supply samples for a research project, it revealed many questions on details that may be answered in more than one way, pointing that all biobanks need to be controlled by a higher degree of management party which develops and offers quality standards for these establishments.


Assuntos
Neoplasias da Mama , Bancos de Tecidos/ética , Bancos de Tecidos/organização & administração , Bancos de Tecidos/normas , DNA , Feminino , Humanos , Projetos Piloto , RNA , Manejo de Espécimes/ética , Manejo de Espécimes/métodos , Manejo de Espécimes/normas , Turquia
6.
Biochimie ; 87(3-4): 343-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15781321

RESUMO

Matrix metalloproteinases (MMP's) and tissue inhibitors of metalloproteinases (TIMP's) possess a preponderant role in the metabolism of the major extracellular matrix protein, collagen, and are thought to be important in the mechanism of tumor invasion. Lung cancer occupies the first position in mortality and the second position in incidence, among all cancers. In the present investigation, we studied the effect of basic fibroblast growth factor (bFGF) on collagen, matrix metalloproteinase-2 (MMP-2), and tissue metalloproteinase inhibitor-2 (TIMP-2) levels in normal and carcinoma lung tissue fibroblast cultures. MMP-2 was selected because of its high specificity in the degradation of type IV collagen, major component of the basal membrane. The effect of bFGF on MMP-2, TIMP-2, total collagen, and type I collagen levels of normal and carcinoma lung fibroblast cultures was investigated at 0, 10, and 100 ng/ml. Statistical analysis was carried out using the Mann-Whitney-U test and possible correlations were searched using the Spearman correlation analysis method. MMP-2, TIMP-2, total collagen, and type-1 collagen levels based on cell counts (10(3) cells) showed no statistically significant differences between the carcinoma and normal fibroblast cultures. However, positive correlations were found between MMP-2 and TIMP-2 in normal (P = 0.016) and carcinoma (P = 0.001) tissue fibroblast cultures. Positive correlations were also found between total collagen and TIMP-2 levels in normal and carcinoma tissue fibroblast cultures (P = 0.002 and P = 0.032). Total collagen and TIMP-2 levels also showed positive and strong correlations in all cultures except in 100 ng/ml bFGF concentrations. In addition, type I collagen and MMP-2 levels showed positive significant correlations only in normal and carcinoma control cultures, while type I collagen and TIMP-2 levels showed positive correlations in all cultures except carcinoma fibroblasts at 100 ng/ml bFGF. It may be concluded that bFGF does not affect MMP-2, TIMP-2, total collagen, and type-1 collagen levels in fibroblast cultures grown from human carcinoma and normal lung tissues. However, bFGF was noted, in vitro, to disturb the equilibrium which normally exists between the four parameters, both in normal and carcinoma tissue fibroblasts.


Assuntos
Carcinoma/patologia , Colágeno Tipo I/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fibroblastos/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Metaloproteinase 2 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Humanos , Análise de Regressão
7.
Int J Cardiol ; 91(1): 53-7, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12957729

RESUMO

It is known that in the presence of oxygen radicals, anti-atherogenic nitric oxide is converted into pro-atherogenic products, which increase lipid peroxidation. In this study, plaque-free atherosclerotic tissues (n=26), atherosclerotic plaques (n=26) and fetal tissues (n=2; as control) were evaluated. High nitrite, but low malondialdehyde, levels in non-atherosclerotic tissues may show the protective role of nitric oxide from atherosclerosis. In plaque-developed tissues nitrite levels were three times, and lipid peroxidation levels were 10 times, higher than non-plaque developed tissues. In the atherosclerotic plaque forming process, the role of nitric oxide can be discovered according to the lipid peroxidation of tissues. In conclusion, the results of this study show an inversely proportional relation between pro- and anti-atherogenic effects of nitric oxide in the pathogenesis of atherosclerotic vascular diseases.


Assuntos
Arteriosclerose/fisiopatologia , Peroxidação de Lipídeos , Óxido Nítrico/análise , Arteriosclerose/patologia , Biomarcadores/análise , Biópsia por Agulha , Humanos , Técnicas In Vitro , Malondialdeído/análise
8.
Allergol Immunopathol (Madr) ; 30(2): 79-84, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11958739

RESUMO

Atherosclerosis in childhood has a slowly progressive course and its clinical features usually become prominent in middle ages. Hypercholesterolemia is one of the major risk factors for the development of atherosclerosis. A clear correlation exists between hypercholesterolemia in childhood and atherosclerotic lesions extending into adulthood.In this study, we evaluated the effect of slow release theophylline (SRT) treatment on plasma lipid profile and assessed the risk for atherosclerotic coronary heart disease in children with bronchial asthma. Group 1 consisted of 15 children with a mean age of 10.8 3.19 years who received SRT for bronchial asthma for a mean period of 9.13 2.17 months. Group 2 was composed of 15 children with a mean age of 11.40 3.78 years and followed up for bronchial asthma, who received no SRT treatment. Group 3 comprised 15 children with a mean age of 9.00 3.76 years and no history of asthma or wheezing. In all patients lipid profiles were assessed by measuring levels of plasma triglyceride, total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) apolipoprotein A (Apo-A) and apolipoprotein B (Apo-B). In group 1, the mean total cholesterol level was 175.53 24.36 mg/dl, LDL-C level was 91.00 24.07 mg/dl and Apo-B level was 87.27 12.74 mg/dl after SRT treatment. In group 1, group 2 (control group with asthma) and group 3 (the non-asthmatic control group), the mean plasma lipid level after SRT treatment was significantly higher than that before SRT treatment. In conclusion, long-term SRT treatment in children with bronchial asthma may alter lipid profile and may increase the risk for developing atherosclerotic coronary heart disease.


Assuntos
Antiasmáticos/efeitos adversos , Asma/sangue , Asma/tratamento farmacológico , Lipoproteínas/sangue , Teofilina/efeitos adversos , Antiasmáticos/administração & dosagem , Criança , Preparações de Ação Retardada , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Teofilina/administração & dosagem
9.
Allergol. immunopatol ; 30(2): 79-84, mar. 2002. tab
Artigo em Inglês | IBECS | ID: ibc-134818

RESUMO

Atherosclerosis in childhood has a slowly progressive course and its clinical features usually become prominent in middle ages. Hypercholesterolemia is one of the major risk factors for the development of atherosclerosis. A clear correlation exists between hypercholesterolemia in childhood and atherosclerotic lesions extending into adulthood. In this study, we evaluated the effect of slow release theophylline (SRT) treatment on plasma lipid profile and assessed the risk for atherosclerotic coronary heart disease in children with bronchial asthma. Group 1 consisted of 15 children with a mean age of 10.8 ± 3.19 years who received SRT for bronchial asthma for a mean period of 9.13 ± 2.17 months. Group 2 was composed of 15 children with a mean age of 11.40 ± 3.78 years and followed up for bronchial asthma, who received no SRT treatment. Group 3 comprised 15 children with a mean age of 9.00 ± 3.76 years and no history of asthma or wheezing. In all patients lipid profiles were assessed by measuring levels of plasma triglyceride, total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) apolipoprotein A (Apo-A) and apolipoprotein B (Apo-B). In group 1, the mean total cholesterol level was 175.53 ± 24.36 mg/dl, LDL-C level was 91.00 ± 24.07 mg/dl and Apo-B level was 87.27 ± 12.74 mg/dl after SRT treatment. In group 1, group 2 (control group with asthma) and group 3 (the non-asthmatic control group), the mean plasma lipid level after SRT treatment was significantly higher than that before SRT treatment. In conclusion, long-term SRT treatment in children with bronchial asthma may alter lipid profile and may increase the risk for developing atherosclerotic coronary heart disease (AU)


La arteriosclerosis en la infancia experimenta un desarrollo progresivo lento y su descubrimiento clínico se suele producir en la edad madura. La hipercolesterolemia es uno de los mayores factores de riesgo en el desarrollo de arteriosclerosis. Existe una relación definida entre la hipercolesterolemia en la infancia y la prolongación de las lesiones arterioscleróticas en la edad adulta. En este estudio hemos evaluado el efecto de un tratamiento con teofilina de liberación prolongada en un perfil de lípido plasmático y hemos descrito el riesgo de arteriosclerosis coronaria en niños con asma bronquial. Quince niños con una edad media de 10,8 ± 3,19 años y que recibieron TLP durante un tiempo medio de 9,13 ± 2,17 meses contra el asma bronquial fueron clasificados como grupo 1; 15 niños con una edad media de 11,40 ± 3,78, expuestos a un seguimiento por asma bronquial y que no recibieron el tratamiento con TPL fueron clasificados como grupo 2; 15 niños con una edad media de 9,00 ± 3,76 años que no presentaban un historial de asma ni de disnea sibilante fueron clasificados como grupo 3. Los perfiles de lípidos se cuantificaron con mediciones de los niveles de triglicéridos en plasma, colesterol total, lipoproteínas de alta densidad (LAD), lipoproteínas de baja densidad (LBD), apolipoproteína A (Apo-A) y apolipoproteína B (Apo-B) a todos los pacientes objeto de este estudio. El nivel medio de colesterol total se determinó en 175,53 ± 24,36 mg/dl, el nivel de LBD en 91,00 ± 24,07 mg/dl y el nivel Apo-B en 87,27 ± 12,74 mg/dl en el primer grupo tras el tratamiento con TPL. El nivel medio de lípidos en plasma tras el tratamiento con TLP fue significativamente más alto que el nivel medio de lípidos antes del tratamiento en el Grupo 1, en el Grupo 2 (grupo de control con asma) y en el Grupo 3 (grupo de control sin asma). En conclusión, el tratamiento con TLP a largo plazo en niños con asma bronquial puede alterar el perfil de lípidos y puede incrementar el riesgo de padecer cardiopatías coronarias por arteriosclerosis en los niños con asma bronquial (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Teofilina/farmacocinética , Asma/tratamento farmacológico , Aterosclerose/epidemiologia , Hipercolesterolemia/epidemiologia , Preparações de Ação Retardada/farmacocinética , Lipoproteínas/análise
10.
Clin Exp Med ; 1(4): 187-93, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11918277

RESUMO

The objective of this study was to elucidate the glycation and oxidation processes in plasma and erythrocyte membrane proteins as well as the major erythrocyte cytoskeletal protein, spectrin, using a short-term experimental rabbit diabetes model. Diabetes was induced with a single-dose alloxan injection. Spectrin was purified from erythrocyte ghosts with selective solubilization followed by gel filtration chromatography techniques, and tested for purity using sodium dodecyl sulfate-poly-acrylamide gel electrophoresis. Glycation in plasma proteins was measured as fructosamine using the nitroblue tetrazolium method, and in erythrocyte membrane and purified spectrin, as ketoamine equivalents, by the hydrazine/phenylhydrazine method. Protein oxidation in plasma, erythrocyte membrane proteins, and purified spectrin was evaluated in terms of sulfhydryl oxidation, based on cis-dichlorodiammine platinum (II) binding. Carbonyl formation was also measured in plasma and membrane proteins. Sulfhydryl oxidation, carbonyl groups and glycated protein levels showed statistically significant differences between the diabetic and control groups for both the plasma and the erythrocyte membrane proteins. The cis-dichlorodiammine platinum (II) binding was significantly different in diabetic rabbit erythrocyte spectrin, while glycation was not significantly different for this protein. Our data clearly demonstrate that both protein glycation and oxidation are biochemical alterations occurring in diabetes, even of short duration.


Assuntos
Diabetes Mellitus Experimental/sangue , Eritrócitos/metabolismo , Espectrina/química , Animais , Glicemia/metabolismo , Membrana Eritrocítica/metabolismo , Frutosamina/sangue , Glicosilação , Masculino , Proteínas de Membrana/sangue , Proteínas de Membrana/química , Oxirredução , Coelhos
11.
J Int Acad Periodontol ; 3(1): 1-6, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12666971

RESUMO

Collagen is one of the chief components of the extracellular matrix of gingival connective tissue, where five different types have been identified to date. The molecular mechanism of collagen loss in periodontitis still needs to be explored. In the present study total collagen content was investigated in gingival connective tissue of adult periodontitis (AP) as well as early onset periodontitis patients (EOP) and clinically healthy subjects. Furthermore, collagen type I, III, IV, V andVI content was evaluated in gingival biopsies obtained from periodontitis patients. There was a statistically significant difference between AP (25.1 +/- 8.1 microg/mg) and EOP (15.6 +/- 4.0microg/mg) groups with regard to the total collagen content (P < 0.05). In the clinically healthy control group the total collagen content was 20.7 +/- 4.6microg/mg. Moreover, the distribution of collagen types exhibited variations in pooled homogenates of each periodontitis group. The total collagen loss seemed to be greater in the EOP patients than in the AP patients. When the ratio of fibril forming collagens to nonfibrillar collagens was evaluated, it seems to be decreased in AP patients in comparison to EOP patients. The findings of the present study suggest that different collagen types present in various periodontitis categories may be related with diverse pathogenic mechanisms acting in these diseases.


Assuntos
Colágeno/análise , Gengiva/química , Periodontite/metabolismo , Adolescente , Adulto , Idoso , Periodontite Agressiva/metabolismo , Análise de Variância , Biópsia , Colágeno/classificação , Colágeno Tipo I/análise , Colágeno Tipo III/análise , Colágeno Tipo IV/análise , Colágeno Tipo V/análise , Colágeno Tipo VI/análise , Tecido Conjuntivo/química , Feminino , Colágenos Fibrilares/análise , Gengivite/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Colágenos não Fibrilares/análise , Bolsa Periodontal/metabolismo , Periodonto/química , Estatística como Assunto
12.
Brain Res ; 843(1-2): 18-24, 1999 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-10528106

RESUMO

This investigation was conducted in rat brain tissues to elucidate the free radical induced cellular and subcellular membrane injuries in two different depth of global ischemia. Global moderate (penumbral) ischemia was performed on rat brains by bilateral vertebral arteries cauterization and temporary occlusion of the bilateral carotid arteries. Global severe ischemia was produced by a neck tourniquet in addition to four vessel occlusion. Somatosensory evoked potentials (SSEPs) were used as a feed back parameter to monitor electrophysiologically the ischemia. At the end of ischemic insult (0 min reperfusion) or various reperfusion periods (20, 60 and 240 min), all rats were decapitated and brains were frozen in liquid nitrogen. The brain tissues were prepared for the determination of cathepsin L (CL) and acid phosphatase (AP) activities in the supernatant (cytosolic) fraction (SF) and the fraction enriched with lysosomes (FEL). Further the level of thiobarbituric acid reactive substances (TBARS) of lipid peroxidation was assessed by the spectrophotometric methods. Severe ischemia-reperfusion was accompanied by a significant increase in TBARS levels and the SF/FEL ratio for CL and AP activities compared to the sham operated group and the concurrent reperfusion groups of moderate ischemia (p<0.05). There were no significant differences between the sham operated and moderate ischemia-reperfusion groups for the same parameters. Our data clearly demonstrate that; in rat brain although severe ischemia-reperfusion causes lipid peroxidation in cellular membranes and redistribution of lysosomal enzymes from lysosomes to cytoplasm due to lysosomal membrane injury, there are no changes in lysosomal membrane stability in moderate ischemia-reperfusion.


Assuntos
Fosfatase Ácida/metabolismo , Encéfalo/metabolismo , Catepsinas/metabolismo , Endopeptidases , Ataque Isquêmico Transitório/metabolismo , Peroxidação de Lipídeos , Reperfusão , Animais , Pressão Sanguínea , Catepsina L , Cisteína Endopeptidases , Potenciais Somatossensoriais Evocados , Ataque Isquêmico Transitório/fisiopatologia , Lisossomos/enzimologia , Masculino , Prosencéfalo/metabolismo , Ratos , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Fatores de Tempo
13.
Res Exp Med (Berl) ; 199(3): 167-76, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10639700

RESUMO

Free radicals are thought to be the most important cause of the reperfusion injury subsequent to ischemia. The antioxidant status of the tissue affected by ischemia-reperfusion is of great importance for the primary endogenous defense against the free radical induced injury. This investigation was performed to evaluate the antioxidant enzyme capacity of the brain tissue in the ischemia-reperfusion period using an experimental global moderate (penumbral) ischemia model on rat brains. Experiments were performed on 45 male Sprague Dawley rats. Ischemia was induced by bilateral vertebral arteries cauterization and temporary bilateral carotid arteries occlusion and sustained for 10 minutes. At the end of ischemia (0 min reperfusion) and various reperfusion periods (20 min, 60 min, 240 min), rats were decapitated and brains were frozen in liquid nitrogen. Changes in the intracellular antioxidant enzyme (superoxide dismutase, glutathione peroxidase and catalase) activities were assessed in the rat brain tissues, by spectrophotometric methods. In all moderate ischemia-reperfusion groups, superoxide dismutase activities were found to have decreased significantly compared to the sham operated controls (P < 0.05). During ischemia superoxide dismutase activity was lowered to 31% of that of the control group. The decreases were more significant in reperfusion groups, particularly in 60 min reperfusion (40%). Relatively smaller but still significant diminution was observed in glutathione peroxidase activities (P < 0.05). The ratio of diminution was striking in 20 min and 60 min reperfusion groups with 26% of the sham operated rats. Conversely, moderate ischemia-reperfusion caused significant increase in catalase activities (P < 0.05). The increment was 63% of the preischemic level with 10 min of moderate ischemia. In conclusion, activities of the major antioxidant enzymes were changed significantly in moderate brain ischemia-reperfusion. These results suggest that the disturbance in oxidant-antioxidant balance might play a part in rendering the tissue more vulnerable to free radical induced injuries.


Assuntos
Lesões Encefálicas/enzimologia , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Traumatismo por Reperfusão/enzimologia , Superóxido Dismutase/metabolismo , Animais , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Isquemia Encefálica/enzimologia , Isquemia Encefálica/metabolismo , Radicais Livres/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo
15.
Eur Surg Res ; 30(4): 227-34, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9704748

RESUMO

In this experimental study, we evaluated the effect of trimetazidine (TMZ) on renal ischemia-reperfusion (IR) injury in Sprague-Dawley rats. Renal IR was achieved by a 75-min clamping of the left renal pedicle and subsequent 24 h reperfusion, after right nephrectomy was performed. The rats were randomly divided into three groups: group 1 (sham-operated: no IR injury), group 2 (ischemic control: saline treatment), and group 3 (3 mg/kg TMZ before ischemia). After 24 h of reperfusion, blood samples and renal tissue samples were taken to measure the levels of creatinine, tissue malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) activity. Histopathological changes were evaluated. In addition, the 7-day survival rates in each group were evaluated. We found significant increases in the levels of creatinine and tissue MDA, severe acute tubular necrosis, and a significant decrease in the activity of the GSH-Px in group 2. There were significant decreases in the levels of creatinine and tissue MDA, mild acute tubular necrosis, and a significant increase in activity of the GSH-Px in group 3 when compared with the control group (p <0.05). Statistically significant differences (p <0.05) in survival were noted between the ischemic control and sham-operated and TMZ groups. We have concluded that TMZ is able to protect the kidney from warm IR injury.


Assuntos
Isquemia/tratamento farmacológico , Rim/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Trimetazidina/farmacologia , Vasodilatadores/farmacologia , Animais , Glutationa/metabolismo , Isquemia/metabolismo , Isquemia/patologia , Rim/metabolismo , Rim/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
16.
Surg Laparosc Endosc ; 8(3): 233-6, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9649051

RESUMO

We present a case of sacroiliac fusion performed for an intraarticular osteochondroma of the sacroiliac joint, which was the cause of severe pain and disability. Excision of the lesion and sacroiliac fusion were successfully performed by utilizing minimally invasive surgical techniques. Although the application of this technique requires a dedicated and highly experienced team, the encouraging result of our first case, with minimal morbidity and disability due to the operation, induces us to recommend this technique in sacroiliac fusion, especially when fusion is combined with additional procedures such as drainage, biopsy, or excision.


Assuntos
Neoplasias Ósseas/cirurgia , Endoscopia/métodos , Osteocondroma/cirurgia , Articulação Sacroilíaca/cirurgia , Fusão Vertebral/métodos , Adulto , Neoplasias Ósseas/diagnóstico , Seguimentos , Humanos , Masculino , Osteocondroma/diagnóstico , Gravação em Vídeo
18.
J Cardiovasc Pharmacol Ther ; 2(4): 285-290, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10684469

RESUMO

BACKGROUND: The metabolic and hemodynamic effects of nisoldipine supplementation in cardioplegia after ischemic injury were investigated in 13 isolated rabbit hearts. Group 1 consisted of 6 hearts, which received St. Thomas II cardioplegic solution. In group 2, nisoldipine was added to the cardioplegic solution at a concentration of 0.1 mg/kg in 7 hearts. METHODS: The explanted hearts were suspended from Langendorff apparatus and were perfused with Krebs-Henseleit solution. Left ventricular pressure, heart rate, malondialdehyde, glutathione peroxidase, glutathione reductase, reduced glutathione, oxidized glutathione, creatine kinase MB, (CK-MB), aspartate transaminase, and lactate dehydrogenase (LDH) were measured before and after 60 minutes of ischemia. Peak generated pressure after ischemia was significantly higher in group 2 versus group 1 while end-diastolic pressure was significantly lower in group 2 after ischemic arrest (P <.05). RESULTS: Malondialdehyde levels were lower in group 2 (P <.05). Glutathione peroxidase and glutathione reductase levels were significantly higher in group 2 (P <.05). The only enzymatic significant difference was observed between the preischemic and postischemic levels of aspartate transaminase in group 2 (P <.05). CONCLUSIONS: These findings show beneficial effects of nisoldipine cardioplegia, although its use as a cardioplegic additive is not yet possible. We believe, however, the effects of oral nisoldipine before cardiac surgery can be studied in a clinical setting.

19.
J Intern Med ; 242(6): 449-54, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9437405

RESUMO

OBJECTIVES: To examine the impact of diabetic state on the concentrations of lipoprotein(a) [Lp(a)] in patients with non-insulin-dependent diabetes mellitus (NIDDM) and the correlation between angiographic coronary artery disease (CAD) and serum Lp(a) concentrations in NIDDM. DESIGN: In this cross-sectional study of 26 patients with NIDDM and 19 nondiabetic sex- and age-matched patients who underwent coronary angiography. CAD was assessed visually using coronary artery score (CAS), and plasma Lp(a) was measured by an enzyme-linked immunosorbent assay. SETTING: The study was performed in an internal medicine clinic at a university hospital. SUBJECTS: Twenty-six age- and sex-matched patients with NIDDM and 19 control patients without diabetes. RESULTS: There was no significant difference between the Lp(a) concentrations of patients with NIDDM and nondiabetic subjects (P > 0.05). When patients with NIDDM were stratified by absence or presence of CAD, patients with CAD had higher levels of Lp(a) (P < 0.05). However, there was no significant correlation between the concentrations of Lp(a) and CAS (P > 0.05). CONCLUSIONS: Diabetic state does not have any impact on Lp(a) concentrations. Lp(a) excess seems to be atherogenic in patients with NIDDM as shown in nondiabetic patients in previous studies. Although diabetic patients with CAD have higher Lp(a) concentrations than the diabetic patients without CAD, Lp(a) levels were not correlated with CAS.


Assuntos
Angiografia Coronária , Doença das Coronárias/complicações , Diabetes Mellitus Tipo 2/complicações , Lipoproteína(a)/sangue , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico por imagem , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade
20.
Cancer Lett ; 119(1): 13-9, 1997 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18372516

RESUMO

This study was performed to elucidate the lung glutathione-related defense potential in tumoral tissues. Reduced (GSH) and oxidized (GSSG) glutathione, glutathione reductase (GR), selenium-dependent (SeGPx) and total glutathione peroxidase (tGPx), and glutathione S-transferase (GST) activities in 38 tumoral lung tissues and 17 normal lung tissues were determined to obtain a comprehensive profile of the lung glutathione and glutathione-related enzymes in cancer. The enzyme levels in tumoral tissues (n = 38) were found to be significantly higher (P < 0.05) than those in normal tissues (n = 17). Reduced glutathione levels, and not oxidized glutathione levels, were found to be higher in normal tissues than those in tumoral tissues. We found no statistically significant difference between the adenocarcinoma and squamous cell carcinoma groups for any of the parameters studied.


Assuntos
Glutationa Peroxidase/análise , Glutationa Redutase/análise , Glutationa Transferase/análise , Glutationa/análise , Neoplasias Pulmonares/química , Humanos
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