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1.
Bone Marrow Transplant ; 52(6): 859-862, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28287644

RESUMO

Acute GvHD (aGvHD) is a life-threatening complication of hematopoietic stem cell transplantation. Frontline therapy for aGvHD consists of corticosteroid administration. However, ∼25% of the patients have a steroid-refractory disease, a sign of poor prognosis. An alternative therapy for steroid-refractory aGvHD is infusion of mesenchymal stromal cells (MSCs). Herein, we report the results of 46 patients treated with MSC infusion as salvage therapy for steroid-refractory aGvHD III/IV (78% grade IV). Patients received a median cumulative dose of MSCs of 6.81 × 106/kg (range, 0.98-29.78 × 106/kg) in a median of 3 infusions (range, 1-7). Median time between the onset of aGvHD and the first MSC infusion was 25.5 days (range, 6-153). Of the patients, 50% (23/46) presented clinical improvement. Of these, 3 patients (13%) had complete response, 14 (61%) had partial response and 6 (26%) had transient partial response. The estimated probability of survival at 2s year was 17.4%. Only 2 patients (4.3%) presented acute transient side effects (nausea/vomiting and blurred vision) during cell infusion. No patient had late or severe side effects because of MSC infusion. These results suggest that this therapeutic modality is safe and should be considered for steroid-refractory aGvHD, especially in countries where other second-line agents are less available.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Doença Aguda , Adolescente , Adulto , Idoso , Aloenxertos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/terapia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Esteroides/administração & dosagem , Taxa de Sobrevida
2.
Cell Biochem Funct ; 29(7): 543-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21989892

RESUMO

Pulmonary arterial hypertension (PAH) is a disease that increases the pulmonary vascular resistance, causing hypertrophy and subsequent right heart failure. Oxidative stress is involved in the pathogenesis of PAH, and estrogen is considered an antioxidant. Thus, the aim of this study was to test the hypothesis that estrogen could attenuate PAH by modulating oxidative stress. Female Wistar rats were ovariectomized or suffered the surgery simulation (sham). After 7 days, subcutaneous pellets with 17ß-estradiol or sunflower oil were implanted. At this time, PAH was induced by means of a single dose of monocrotaline (MCT) (60 mg·kg(-1) i.p.). The experimental groups were as follows: (1) sham, (2) sham + MCT, (3) ovariectomy (O), (4) ovariectomy + MCT (OM), (5) ovariectomy + estrogen replacement + MCT (ORM). Hemodynamic measurements were performed 21 days after MCT or saline. Nonovariectomized animals were assessed in the stage of diestrus. Afterwards, the rats were killed to collect the heart, the lung and the liver to evaluate morphometry. Samples of the right ventricle were used to analyse the reduced glutathione : oxidized glutathione ratio. Lung congestion in the OM group, which was decreased in the ORM group, was observed. Right ventricle end-diastolic pressure was increased in the OM and the ORM groups. The glutathione ratio decreased in the groups O, OM and ORM. The data suggest that estrogen can exert great influence on the cellular redox balance. The maintenance of physiological estrogen levels may help to avoid the appearance of pulmonary oedema, characteristic of this model of PAH, and right ventricular failure.


Assuntos
Estradiol/farmacologia , Hipertensão Pulmonar/tratamento farmacológico , Estresse Oxidativo , Animais , Western Blotting , Peso Corporal , Diestro/fisiologia , Estradiol/administração & dosagem , Feminino , Glutationa/metabolismo , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/fisiopatologia , Monocrotalina/administração & dosagem , Monocrotalina/efeitos adversos , Ovariectomia , Óleos de Plantas/administração & dosagem , Artéria Pulmonar/fisiopatologia , Ratos , Ratos Wistar , Óleo de Girassol
3.
Cell Biochem Funct ; 29(7): 617-23, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21989893

RESUMO

This study was conducted to analyse the redox status and redox-sensitive proteins that may contribute to a non-genomic mechanism of cardiac hypertrophy induction by hyperthyroidism. Wistar rats, treated with L-thyroxine (T4) during 2 weeks (12 mg·l(-1) in drinking water), presented cardiac hypertrophy (68% higher than control), without signals of liver or lung congestion. Myocardial reduction of the reduced glutathione: oxidized glutathione (GSSG) ratio (45%) (redox status) and elevation in hydrogen peroxide concentration (H(2) O(2) ) (28%) were observed in hyperthyroid as compared with the control. No significant difference was found in thioredoxin (Trx), Trx reductase activity and Nrf2 (a transcriptional factor) protein expression between groups. Redox-sensitive proteins, quantified using Western blot, presented the following results: increased p-ERK: total extracellular-regulated kinase (ERK) (200%) and Bax:Bcl-2 (62%) ratios and reduced total-Akt (63%) and p-Akt (53%) expressions in the hyperthyroid rats as compared with the control. The redox imbalance, associated with increased immunocontent of a protein related to maladaptative growth (ERK) and reduced immunocontent of protein related to cytoprotection/survival (Akt), may suggest that the molecular scenario could favour the decompensation process of cardiac hypertrophy induced by experimental hyperthyroidism.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Cardiomegalia/induzido quimicamente , Hipertireoidismo/induzido quimicamente , Tiroxina/efeitos adversos , Animais , Western Blotting , Cardiomegalia/patologia , Morte Celular , Água Potável/administração & dosagem , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Hipertireoidismo/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Modelos Animais , Oxirredução , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Tiorredoxinas/metabolismo , Tiroxina/administração & dosagem , Tiroxina/farmacologia , Proteína X Associada a bcl-2/metabolismo
4.
Braz. j. med. biol. res ; 42(10): 892-901, Oct. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-526182

RESUMO

Shock and resuscitation render patients more susceptible to acute lung injury due to an exacerbated immune response to subsequent inflammatory stimuli. To study the role of innate immunity in this situation, we investigated acute lung injury in an experimental model of ischemia-reperfusion (I-R) followed by an early challenge with live bacteria. Conscious rats (N = 8 in each group) were submitted to controlled hemorrhage and resuscitated with isotonic saline (SS, 0.9 percent NaCl) or hypertonic saline (HS, 7.5 percent NaCl) solution, followed by intratracheal or intraperitoneal inoculation of Escherichia coli. After infection, toll-like receptor (TLR) 2 and 4 mRNA expression was monitored by RT-PCR in infected tissues. Plasma levels of tumor necrosis factor α and interleukins 6 and 10 were determined by ELISA. All animals showed similar hemodynamic variables, with mean arterial pressure decreasing to nearly 40 mmHg after bleeding. HS or SS used as resuscitation fluid yielded equal hemodynamic results. Intratracheal E. coli inoculation per se induced a marked neutrophil infiltration in septa and inside the alveoli, while intraperitoneal inoculation-associated neutrophils and edema were restricted to the interseptal space. Previous I-R enhanced lung neutrophil infiltration upon bacterial challenge when SS was used as reperfusion fluid, whereas neutrophil influx was unchanged in HS-treated animals. No difference in TLR expression or cytokine secretion was detected between groups receiving HS or SS. We conclude that HS is effective in reducing the early inflammatory response to infection after I-R, and that this phenomenon is achieved by modulation of factors other than expression of innate immunity components.


Assuntos
Animais , Masculino , Ratos , Lesão Pulmonar Aguda/imunologia , Infecções por Escherichia coli/imunologia , Inflamação/imunologia , Traumatismo por Reperfusão/imunologia , Solução Salina Hipertônica/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Doença Aguda , Lesão Pulmonar Aguda/sangue , Lesão Pulmonar Aguda/microbiologia , Citocinas/sangue , Modelos Animais de Doenças , Imunidade Inata , Inflamação/sangue , Inflamação/tratamento farmacológico , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Mensageiro/sangue , Choque Hemorrágico/imunologia , /sangue
5.
Braz J Med Biol Res ; 42(10): 892-901, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19787146

RESUMO

Shock and resuscitation render patients more susceptible to acute lung injury due to an exacerbated immune response to subsequent inflammatory stimuli. To study the role of innate immunity in this situation, we investigated acute lung injury in an experimental model of ischemia-reperfusion (I-R) followed by an early challenge with live bacteria. Conscious rats (N = 8 in each group) were submitted to controlled hemorrhage and resuscitated with isotonic saline (SS, 0.9% NaCl) or hypertonic saline (HS, 7.5% NaCl) solution, followed by intratracheal or intraperitoneal inoculation of Escherichia coli. After infection, toll-like receptor (TLR) 2 and 4 mRNA expression was monitored by RT-PCR in infected tissues. Plasma levels of tumor necrosis factor alpha and interleukins 6 and 10 were determined by ELISA. All animals showed similar hemodynamic variables, with mean arterial pressure decreasing to nearly 40 mmHg after bleeding. HS or SS used as resuscitation fluid yielded equal hemodynamic results. Intratracheal E. coli inoculation per se induced a marked neutrophil infiltration in septa and inside the alveoli, while intraperitoneal inoculation-associated neutrophils and edema were restricted to the interseptal space. Previous I-R enhanced lung neutrophil infiltration upon bacterial challenge when SS was used as reperfusion fluid, whereas neutrophil influx was unchanged in HS-treated animals. No difference in TLR expression or cytokine secretion was detected between groups receiving HS or SS. We conclude that HS is effective in reducing the early inflammatory response to infection after I-R, and that this phenomenon is achieved by modulation of factors other than expression of innate immunity components.


Assuntos
Lesão Pulmonar Aguda/imunologia , Infecções por Escherichia coli/imunologia , Inflamação/imunologia , Traumatismo por Reperfusão/imunologia , Solução Salina Hipertônica/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Doença Aguda , Lesão Pulmonar Aguda/sangue , Lesão Pulmonar Aguda/microbiologia , Animais , Citocinas/sangue , Modelos Animais de Doenças , Imunidade Inata , Inflamação/sangue , Inflamação/tratamento farmacológico , Masculino , RNA Mensageiro/sangue , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Choque Hemorrágico/imunologia , Receptor 2 Toll-Like/sangue
6.
Thorac Cardiovasc Surg ; 57(5): 309-11, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19629897

RESUMO

The overproduction of reactive oxygen species plays an important role in the cascade of events during lung ischemia-reperfusion leading to graft failure. An evaluation of the peripheral markers of oxidative stress and antioxidant enzyme activities was carried out after reperfusion in a rat lung transplant model. The decrease in lipid peroxidation immediately after transplantation ( P < 0.05) may suggest an adaptative response and/or a protective effect of low potassium dextran against lipid peroxidation through natural scavenging mechanisms.


Assuntos
Eritrócitos/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Transplante de Pulmão , Soluções para Preservação de Órgãos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Animais , Catalase/metabolismo , Dextranos/farmacologia , Eritrócitos/enzimologia , Glucose/farmacologia , Masculino , Modelos Animais , Ratos , Ratos Wistar , Traumatismo por Reperfusão/sangue , Superóxido Dismutase/metabolismo , Fatores de Tempo
7.
J Mol Endocrinol ; 41(6): 423-30, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18787053

RESUMO

This study was conducted to test whether oxidative stress activates the intracellular protein kinase B (AKT1) signaling pathway, which culminates with cardiac hypertrophy in experimental hyperthyroidism. Male Wistar rats were divided into four groups: control, vitamin E, thyroxine (T(4)), and T(4)+vitamin E. Hyperthyroidism was induced by T(4) administration (12 mg/l in drinking water for 28 days). Vitamin E treatment was given during the same period via s.c. injections (20 mg/kg per day). Morphometric and hemodynamic parameters were evaluated at the end of the 4-week treatment period. Protein oxidation, redox state (reduced glutathione, GSH/glutathione dissulfide, GSSG), vitamin C, total radical-trapping antioxidant potential (TRAP), hydrogen peroxide (H2O2), and nitric oxide metabolites (NO(X)) were measured in heart homogenates. The p-AKT1/AKT1 ratio, p-glycogen-synthase kinase (GSK)3B/GSK3B ratio, FOS, and JUN myocardial protein expression were also quantified by western blot after 4 weeks. Increases in biochemical parameters, such as protein oxidation (41%), H2O2 (62%), and NO(X) (218%), and increase in the left ventricular end-diastolic pressure were observed in the T(4) group. T(4) treatment also caused a decrease in GSH/GSSG ratio (83%), vitamin C (34%), and TRAP (55%). These alterations were attenuated by vitamin E administration to the hyperthyroid rats. Expression of p-AKT1/AKT1, p-GSK3B/GSK3B, FOS, and JUN were elevated in the T(4) group (by 69, 37, 130, and 33% respectively), whereas vitamin E administration promoted a significant reduction in their expression. These results indicate that oxidative stress plays an important role in cardiac hypertrophy, and suggest redox activation of AKT1 and JUN/FOS signaling pathways with H2O2 acting as a possible intracellular mediator in this adaptive response to experimental hyperthyroidism.


Assuntos
Cardiomegalia/etiologia , Modelos Animais de Doenças , Hipertireoidismo/complicações , Transdução de Sinais , Animais , Ácido Ascórbico/metabolismo , Western Blotting , Cardiomegalia/metabolismo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Masculino , Oxirredução , Ratos , Ratos Wistar , Tiroxina/sangue
8.
Mol Cell Biochem ; 303(1-2): 89-95, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17447016

RESUMO

Thyroxine can cause cardiac hypertrophy by activating growth factors, such as IGF-I (insulin-like growth factor-I). Since oxidative stress is enhanced in the hyperthyroidism, it would control protein expression involved in this hypertrophy. Male Wistar rats were divided into four groups: (I) control, (II) vitamin E-supplemented (20 mg/kg/day subcutaneous), (III) hyperthyroid (thyroxine 12 mg/l, in drinking water), and (IV) hyperthyroid + vitamin E. After 4 weeks, the contractility and relaxation indexes of left ventricle (LV), and cardiac mass were increased by 54%, 60%, and 60%, respectively, in hyperthyroid group. An increase in lipid peroxidation (around 40%), and a decrease in total glutathione (by 20%) was induced by thyroxine and avoided by vitamin E administration. Superoxide dismutase (SOD) and glutathione-S-transferase (GST) activities were increased (by 83% and 54%, respectively) in hyperthyroid, and vitamin E avoided changes in SOD. Protein expression of SOD, GST, and IGF-I receptor (IGF-IR) were increased (by 87%, 84%, and 60%, respectively) by thyroxine, and vitamin E promoted a significant reduction in SOD and IGF-IR expression (by 36% and 17%, respectively). These results indicate that oxidative stress is involved in cardiac hypertrophy, and suggest a role for IGF-IR as a mediator of this adaptive response in experimental hyperthyroidism.


Assuntos
Cardiomegalia/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo , Receptor IGF Tipo 1/metabolismo , Tiroxina/farmacologia , Animais , Antioxidantes/farmacologia , Peso Corporal , Cardiomegalia/induzido quimicamente , Cardiomegalia/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Masculino , Oxirredução , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Tiroxina/sangue , Vitamina E/farmacologia
9.
Braz J Med Biol Res ; 39(6): 767-72, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16751982

RESUMO

The present study was designed to evaluate the time course changes in peripheral markers of oxidative stress in a chronic HgCl2 intoxication model. Twenty male adult Wistar rats were treated subcutaneously daily for 30 days and divided into two groups of 10 animals each: Hg, which received HgCl2 (0.16 mg kg(-1) day(-1)), and control, receiving the same volume of saline solution. Blood was collected at the first, second and fourth weeks of Hg administration to evaluate lipid peroxidation (LPO), total radical trapping antioxidant potential (TRAP), and superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and catalase (CAT). HgCl2 administration induced a rise (by 26%) in LPO compared to control (143 +/- 10 cps/mg hemoglobin) in the second week and no difference was found at the end of the treatment. At that time, GST and GPx were higher (14 and 24%, respectively) in the Hg group, and Cu,Zn-SOD was lower (54%) compared to control. At the end of the treatment, Cu,Zn-SOD and CAT were higher (43 and 10%, respectively) in the Hg group compared to control (4.6 +/- 0.3 U/mg protein; 37 +/- 0.9 pmol/mg protein, respectively). TRAP was lower (69%) in the first week compared to control (43.8 +/- 1.9 mM Trolox). These data provide evidence that HgCl2 administration is accompanied by systemic oxidative damage in the initial phase of the process, which leads to adaptive changes in the antioxidant reserve, thus decreasing the oxidative injury at the end of 30 days of HgCl2 administration. These results suggest that a preventive treatment with antioxidants would help to avoid oxidative damage in subjects with chronic intoxication.


Assuntos
Antioxidantes/análise , Eritrócitos/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Cloreto de Mercúrio/intoxicação , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/sangue , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Doença Crônica , Modelos Animais de Doenças , Luminescência , Masculino , Peroxidases/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
10.
Braz. j. med. biol. res ; 39(6): 767-772, June 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-428268

RESUMO

The present study was designed to evaluate the time course changes in peripheral markers of oxidative stress in a chronic HgCl2 intoxication model. Twenty male adult Wistar rats were treated subcutaneously daily for 30 days and divided into two groups of 10 animals each: Hg, which received HgCl2 (0.16 mg kg-1 day-1), and control, receiving the same volume of saline solution. Blood was collected at the first, second and fourth weeks of Hg administration to evaluate lipid peroxidation (LPO), total radical trapping antioxidant potential (TRAP), and superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and catalase (CAT). HgCl2 administration induced a rise (by 26 percent) in LPO compared to control (143 ± 10 cps/mg hemoglobin) in the second week and no difference was found at the end of the treatment. At that time, GST and GPx were higher (14 and 24 percent, respectively) in the Hg group, and Cu,Zn-SOD was lower (54 percent) compared to control. At the end of the treatment, Cu,Zn-SOD and CAT were higher (43 and 10 percent, respectively) in the Hg group compared to control (4.6 ± 0.3 U/mg protein; 37 ± 0.9 pmol/mg protein, respectively). TRAP was lower (69 percent) in the first week compared to control (43.8 ± 1.9 mM Trolox). These data provide evidence that HgCl2 administration is accompanied by systemic oxidative damage in the initial phase of the process, which leads to adaptive changes in the antioxidant reserve, thus decreasing the oxidative injury at the end of 30 days of HgCl2 administration. These results suggest that a preventive treatment with antioxidants would help to avoid oxidative damage in subjects with chronic intoxication.


Assuntos
Animais , Masculino , Ratos , Antioxidantes/análise , Eritrócitos/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Cloreto de Mercúrio/intoxicação , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/sangue , Antioxidantes/metabolismo , Biomarcadores/sangue , Doença Crônica , Modelos Animais de Doenças , Luminescência , Peroxidases/metabolismo , Ratos Wistar , Fatores de Tempo
11.
Mol Cell Endocrinol ; 249(1-2): 133-9, 2006 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-16574313

RESUMO

Hyperthyroidism was induced in rats by l-thyroxine administration (12 mg/L in drinking water, 4 weeks). Animals were assessed hemodynamically, and heart, lung, and liver morphometry were performed. Lipid peroxidation (LPO) and protein oxidation (carbonyls) were measured in heart homogenates. It was quantified glutathione (GSH) metabolism, and antioxidant enzyme activities its and protein expression (by Western blot). At the end of treatment, it was observed cardiac hypertrophy, elevation of left ventricular systolic and end diastolic pressures, lung and liver congestion. LPO and carbonyls were increased in the hyperthyroid group, and GSH was decreased by 46% in the fourth week. Myocardial oxidative stress time course analysis revealed that it was increased in the second week of treatment. Antioxidant enzyme activities elevation was accompanied by protein expression induction in the hyperthyroid group in the fourth week. These results imply that hyperthyroidism generates myocardial dysfunction associated with oxidative stress inducing antioxidant enzyme activities and protein expression.


Assuntos
Antioxidantes/metabolismo , Glutationa/metabolismo , Hipertireoidismo/metabolismo , Miocárdio/enzimologia , Animais , Catalase/metabolismo , Glutationa Transferase/metabolismo , Cardiopatias/complicações , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/complicações , Peroxidação de Lipídeos , Miocárdio/metabolismo , Oxirredução , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Tiroxina
12.
Braz J Med Biol Res ; 35(9): 1075-81, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12219179

RESUMO

The purpose of the present study was to examine myocardial antioxidant and oxidative stress changes in male and female rats in the presence of physiological sex hormone concentrations and after castration. Twenty-four 9-week-old Wistar rats were divided into four groups of 6 animals each: 1) sham-operated females, 2) castrated females, 3) sham-operated males, and 4) castrated males. When testosterone and estrogen levels were measured by radioimmunoassay, significant differences were observed between the castrated and control groups (both males and females), demonstrating the success of castration. Progesterone and catalase levels did not change in any group. Control male rats had higher levels of glutathione peroxidase (50%) and lower levels of superoxide dismutase (SOD, 14%) than females. Control females presented increased levels of SOD as compared to the other groups. After castration, SOD activity decreased by 29% in the female group and by 14% in the male group as compared to their respective controls. Lipid peroxidation (LPO) was assessed to evaluate oxidative damage to cardiac membranes by two different methods, i.e., TBARS and chemiluminescence. LPO was higher in male controls compared to female controls when evaluated by both methods, TBARS (360%) and chemiluminescence (46%). Castration induced a 200% increase in myocardial damage in females as determined by TBARS and a 20% increase as determined by chemiluminescence. In males, castration did not change LPO levels. These data suggest that estrogen may have an antioxidant role in heart muscle, while testosterone does not.


Assuntos
Antioxidantes/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Miocárdio/enzimologia , Estresse Oxidativo , Análise de Variância , Animais , Castração , Feminino , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/metabolismo , Glutationa Peroxidase/análise , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/fisiologia , Medições Luminescentes , Masculino , Miocárdio/patologia , Ratos , Ratos Wistar , Superóxido Dismutase/análise , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico
13.
Braz. j. med. biol. res ; 35(9): 1075-1081, Sept. 2002. tab, graf
Artigo em Inglês | LILACS | ID: lil-325903

RESUMO

The purpose of the present study was to examine myocardial antioxidant and oxidative stress changes in male and female rats in the presence of physiological sex hormone concentrations and after castration. Twenty-four 9-week-old Wistar rats were divided into four groups of 6 animals each: 1) sham-operated females, 2) castrated females, 3) sham-operated males, and 4) castrated males. When testosterone and estrogen levels were measured by radioimmunoassay, significant differences were observed between the castrated and control groups (both males and females), demonstrating the success of castration. Progesterone and catalase levels did not change in any group. Control male rats had higher levels of glutathione peroxidase (50 percent) and lower levels of superoxide dismutase (SOD, 14 percent) than females. Control females presented increased levels of SOD as compared to the other groups. After castration, SOD activity decreased by 29 percent in the female group and by 14 percent in the male group as compared to their respective controls. Lipid peroxidation (LPO) was assessed to evaluate oxidative damage to cardiac membranes by two different methods, i.e., TBARS and chemiluminescence. LPO was higher in male controls compared to female controls when evaluated by both methods, TBARS (360 percent) and chemiluminescence (46 percent). Castration induced a 200 percent increase in myocardial damage in females as determined by TBARS and a 20 percent increase as determined by chemiluminescence. In males, castration did not change LPO levels. These data suggest that estrogen may have an antioxidant role in heart muscle, while testosterone does not


Assuntos
Animais , Masculino , Feminino , Ratos , Antioxidantes , Hormônios Esteroides Gonadais , Miocárdio , Estresse Oxidativo , Análise de Variância , Castração , Sequestradores de Radicais Livres , Glutationa Peroxidase , Peroxidação de Lipídeos , Medições Luminescentes , Miocárdio , Ratos Wistar , Superóxido Dismutase , Substâncias Reativas com Ácido Tiobarbitúrico
14.
Liver ; 22(1): 35-42, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11906617

RESUMO

AIMS/BACKGROUND: Cellular and extracellular volume changes caused by ATP were investigated in the liver as well as the possible formation of diffusion barriers, which could be responsible for some of its metabolic effects. METHODS: The experimental system was the bivascularly perfused rat liver. [(14)C]Sucrose and [(3)H]water were simultaneously injected into either the portal vein or the hepatic artery. Mean transit times, distribution spaces, variances and linear superimpositions were calculated. RESULTS: In the portal system, ATP reduced the transit time in the great vessels, had little or no effect on sinusoidal and cellular spaces, but impaired the flow-limited distribution of both [(14)C]sucrose and [(3)H]water. In the arterial bed ATP infused into either the portal vein or the hepatic artery produced vasodilation and increased the aqueous extra-sucrose space. These effects were inhibited by Nomega-nitro-L-arginine methyl ester infused into the hepatic artery. CONCLUSIONS: Sucrose and extra-sucrose space changes caused in the arterial bed by portally infused ATP are most probably analogous to the transhepatic vasodilation effect already described for the rabbit liver. Impairment of flow-limited distribution of tracers in the sinusoidal bed indicates that ATP induces the formation of permeability barriers, which could be responsible for some of its metabolic effects.


Assuntos
Trifosfato de Adenosina/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Espaço Extracelular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Permeabilidade da Membrana Celular/fisiologia , Antagonismo de Drogas , Espaço Extracelular/metabolismo , Artéria Hepática/efeitos dos fármacos , Artéria Hepática/fisiologia , Fígado/irrigação sanguínea , Fígado/metabolismo , Circulação Hepática/efeitos dos fármacos , Circulação Hepática/fisiologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Perfusão , Veia Porta/efeitos dos fármacos , Veia Porta/fisiologia , Ratos , Ratos Wistar , Sacarose/metabolismo , Distribuição Tecidual , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Água/metabolismo
15.
Biochem Pharmacol ; 58(3): 397-409, 1999 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10424758

RESUMO

The heterogeneity of the liver parenchyma in relation to the metabolic response to adenosine was investigated using the bivascularly perfused rat liver in the anterograde and retrograde modes. Adenosine was infused into livers from fed rats according to four experimental protocols: (A) anterograde perfusion, adenosine via the portal vein; (B) anterograde perfusion, adenosine via the hepatic artery; (C) retrograde perfusion, adenosine via the hepatic vein; and (D) retrograde perfusion, adenosine via the hepatic artery. Due to the very pronounced concentration gradients generated by metabolic transformation, the infused adenosine attained maximal concentrations in different regions with each experimental protocol. The sinusoidal mean transit times (t(s)) were not changed by adenosine in anterograde perfusion, but were increased in retrograde perfusion. It was concluded that the vasoconstrictive elements are localized essentially in the presinusoidal region. Glucose release stimulation presented two kinetic components. The first one was rapid in both onset and decay with a peak around 30 sec; the second one developed more slowly (several minutes). The factors of the first kinetic component are possibly generated in the presinusoidal region or in the first periportal cells. The initial decrease in oxygen consumption seemed to be localized in the region just after the intrasinusoidal confluence of the ramifications of the portal vein and hepatic artery. Indomethacin decreased glucose release stimulation by adenosine in both anterograde and retrograde perfusion only when DMSO was the vehicle. The participation of eicosanoids in the generation of the effects of adenosine seems to be less important than hitherto believed.


Assuntos
Adenosina/farmacologia , Fígado/efeitos dos fármacos , Vasodilatadores/farmacologia , Adenosina/metabolismo , Animais , Interações Medicamentosas , Eicosanoides/farmacologia , Glucose/metabolismo , Hemodinâmica/efeitos dos fármacos , Indometacina/farmacologia , Cinética , Fígado/fisiologia , Masculino , Oxigênio/metabolismo , Perfusão , Ratos , Ratos Wistar , Vasodilatadores/metabolismo
16.
Mol Cell Biochem ; 195(1-2): 207-17, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10395085

RESUMO

The heterogeneity of the liver parenchyma in relation to uric acid production from adenosine was investigated using the bivascularly perfused rat liver in the anterograde and retrograde modes. Adenosine was infused in livers from fed rats during 20 min at four different concentrations (20, 50, 100 and 200 microM) according to four experimental protocols as follows: (A) anterograde perfusion, with adenosine infusion into the portal vein; (B) anterograde perfusion, with adenosine in the hepatic artery, (C) retrograde perfusion, with adenosine in the hepatic vein; (D) retrograde perfusion, with adenosine in the hepatic artery. With protocols A, B, and D uric acid production from adenosine was always characterized by initial bursts followed by progressive decreases toward smaller steady-states. With protocol C the initial burst was present only when 200 microM adenosine was infused. The initial bursts in uric acid production were accompanied by simultaneous increases in the ratio of uric acid production/adenosine uptake rate. These initial bursts are thus representing increments in the production of uric acid that are not corresponded by similar increments in the metabolic uptake rates of adenosine. Global analysis of uric acid production revealed that the final steady-state rates were approximately equal for all infusion rates with protocols A, B and C, but smaller with protocol D. This difference, however, can be explained in terms of the differences in accessible cellular spaces, which are much smaller when protocol D is employed. When the analysis was performed in terms of the extra amounts of uric acid produced during the infusion of adenosine, where the initial bursts are also taken into account, different dose-response curves were found for each experimental protocol. These differences cannot be explained in terms of the accessible cell spaces and they are likely to reflect regional heterogeneities. From the various dose-response curves and from the known characteristics of the microcirculation of the rat liver it can be concluded that the initial bursts in uric acid production are generated in periportal hepatocytes. The reason for this heterogeneity could be related to the metabolic effects of adenosine, especially to oxygen uptake inhibition, which is likely to produce changes in the ATP/AMP ratios.


Assuntos
Adenosina/metabolismo , Fígado/metabolismo , Perfusão , Ácido Úrico/metabolismo , Adenosina/administração & dosagem , Animais , Artéria Hepática/metabolismo , Veias Hepáticas/metabolismo , Infusões Intravenosas , Fígado/irrigação sanguínea , Fígado/química , Masculino , Consumo de Oxigênio , Perfusão/métodos , Veia Porta/metabolismo , Ratos , Ratos Wistar
17.
J Bras Ginecol ; 95(7): 293-6, 1985.
Artigo em Português | MEDLINE | ID: mdl-12341404

RESUMO

PIP: 500 sexually active women in Brazil aged 15-50 were interviewed to study their use of contraceptives. For the 350 who used contraceptives, the survey evaluated their level of education, marital status, incidence of pregnancy, and the number of abortions performed. The level of education had little effect on the choice of birth control methods. Women with 1 sex partner were more preoccupied with the use of birth control than women who had casual sex with more than 1 partner. The younger women in the group, whether or not they used birth control, had greater frequency of abortions. The preferred method of contraception was the pill, and of the women who took the pill, almost 1/2 did so without a doctor's prescription. 42% of the same group reportedf suffering side effects due to pill use. Since induced abortions are illegal in Brazil, it is certain that the information given is inaccurate. Other methods of birth control also had drawbacks. The early withdrawal method did nothing for the couple's sexual gratification, and was not an effective method of birth control. The rhythm method was rarely used, and could also be dangerous as far as effectiveness. The IUD, which has proven to be very effective in developed nations, was not widely used by this group because it was considered troublesome. It is clear from this report that all means need to be implemented to make birth control accessible to all levels of the population. Failure to utilize birth control methods on moral or religious grounds will cause an increase in abortions, many of which will be performed by unqualified people. The denial of birth control will lead to disastrous consequences.^ieng


Assuntos
Aborto Induzido , Comportamento Contraceptivo , Coleta de Dados , Escolaridade , Serviços de Planejamento Familiar , Estado Civil , Casamento , Características da População , População , História Reprodutiva , Comportamento Sexual , América , Comportamento , Coeficiente de Natalidade , Brasil , Anticoncepção , Atenção à Saúde , Demografia , Países Desenvolvidos , Países em Desenvolvimento , Economia , Fertilidade , Planejamento em Saúde , Acessibilidade aos Serviços de Saúde , Administração de Serviços de Saúde , América Latina , Marketing de Serviços de Saúde , Dinâmica Populacional , Pesquisa , Estudos de Amostragem , Classe Social , Fatores Socioeconômicos , América do Sul
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