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The new competency-based medical education curriculum for Bachelor of Medicine and Bachelor of Surgery is being implemented in a phased manner in medical colleges across India since the year 2019. The Graduate Medical Education Regulations enlist a total of 35 global competencies for the five roles expected of an Indian medical graduate, the roles being clinician, communicator, leader, professional, and life-long learner. Along with an effective implementation of the new curriculum, both in spirit and in action, it is imperative to assess the listed competencies. The new curriculum demands a more careful and mature selection of assessment tools, based on the competency and its expected level of achievement. It is these two variables that make choosing the right assessment method not just a matter of choice, but also of expertise. An array of tools in our armamentarium can sometimes separate confuse and the teachers. So, using the right tool, in the right context, at the right juncture, supplemented by other tools, and backed by constructive feedback, can help nurture the good intent ingrained in the competency-based curriculum. Hence, an attempt was made to compile an assessment toolbox for various global competencies. A PubMed, Science Direct and Google Scholar search, with relevant keywords was carried out. To the initially extracted 90,121 articles, limitations were applied, duplicates were removed and screening for assessment of global competencies and its attributes was done to select 232 articles. Finally, 31 articles were used for designing the proposed toolbox. Prioritization for the tools for the global competencies was based on thorough literature review and extensive discussion. The evolved assessment toolbox is presented in this article, which would help teachers pick the most useful methods of assessment for global competencies.
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Competência Clínica , Educação Baseada em Competências , Currículo , Avaliação Educacional/normas , Feedback Formativo , Educação de Pós-Graduação em Medicina , Humanos , ÍndiaRESUMO
INTRODUCTION: Conventional acid-etching method irreversibly removes several microns of enamel surface and also involves many steps. Hence, a simplified technique that minimizes enamel loss, improves adhesion procedures, prevents saliva contamination, and saves chair time, thereby producing clinically useful bond strength, would be valuable. AIM: To assess and compare the bonding mechanism of a self-etching primer (SEP) to that of phosphoric acid on enamel of the human permanent teeth by a scanning electron microscope (SEM). MATERIALS AND METHODS: Thirty freshly extracted premolars were randomly divided into two groups of fifteen teeth each - the control group I (phosphoric acid) and experimental group II (self-etching primer). Brackets were bonded using Transbond XT adhesive on the buccal surfaces of the teeth after etching and priming according to their respective protocols. The teeth were then sectioned and the samples were subjected to a protocol of demineralization cycles. After complete dissolution of dental tissues, the specimens were gold sputter coated and evaluated under SEM. RESULTS: A characteristically uniform etch pattern was seen in the resin samples of the phosphoric acid/Transbond XT primer group, which revealed increased roughness and resin tags penetrating the demineralized enamel surface, whereas with Transbond Plus SEP, a regular resin tag distribution was observed which showed less magnitude when compared with the control group. CONCLUSION: From the study, it was concluded that Transbond Plus SEP produced an etch pattern which was more conservative than conventional phosphoric acid system.
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Our laboratory reported that Irinophore C™ (IrC™; a lipid-based nanoparticulate formulation of irinotecan) is effective against an orthotopic model of glioblastoma (GBM) and that treatment with IrC™ was associated with vascular normalization within the tumor. Here, the therapeutic effects of IrC™ when used in combination with temozolomide (TMZ) in concurrent and sequential treatment schedules were tested. It was anticipated that IrC™ engendered vascular normalization would increase the delivery of TMZ to the tumor and that this would be reflected by improved treatment outcomes. The approach compared equally efficacious doses of irinotecan (IRN; 50 mg/kg) and IrC™ (25 mg/kg) in order to determine if there was a unique advantage achieved when combining TMZ with IrC™. The TMZ sensitive U251MG(O) cell line (null expression of O-6-methylguanine-DNA methyltransferase (MGMT)) modified to express the fluorescent protein mKate2 was inoculated orthotopically into NOD.CB17-SCID mice and treatment was initiated 14 days later. Our results demonstrated that IrC™ and TMZ administered concurrently resulted in optimal treatment outcomes, with 50% long term survivors (>180 days) in comparison to 17% long term survivors in animals treated with IRN and TMZ or TMZ alone. Indeed, the different treatments resulted in a 353%, 222% and 280% increase in median survival time (MST) compared to untreated animals for, respectively, IrC™ combined with TMZ, IRN combined with TMZ, and TMZ alone. When TMZ was administered after completion of IRN or IrC™ dosing, an increase in median survival time of 167-174% was observed compared to untreated animals and of 67% and 74%, respectively, when IRN (50 mg/kg) and IrC™ (25mg/kg) were given as single agents. We confirmed in these studies that after completion of the Q7D×3 dosing of IrC™, but not IRN, the tumor-associated vascular was normalized as compared to untreated tumors. Specifically, reductions in the fraction of collagen IV-free CD31 staining (p<0.05) and reductions in tumor vessel diameter were observed in tumors from IrC™-treated animals when compared to tumors from untreated or IRN treated animals. Analysis by transmission electron microscopy of the ultra-structure of tumors from IrC™-treated and untreated animals revealed that tumor-associated vessels from treated animals were smaller, more organized and exhibited a morphology comparable to normal blood vessels. In conclusion, optimal treatment outcomes were achieved when IrC™ and TMZ were administered concurrently, whereas IrC™ followed by TMZ treatment given sequentially did not confer any therapeutic advantage.
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Inibidores da Angiogênese/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Camptotecina/análogos & derivados , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Inibidores da Angiogênese/química , Animais , Antineoplásicos Alquilantes/química , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Camptotecina/administração & dosagem , Camptotecina/química , Dacarbazina/administração & dosagem , Dacarbazina/química , Esquema de Medicação , Composição de Medicamentos , Glioblastoma/irrigação sanguínea , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Irinotecano , Lipossomos , Camundongos Endogâmicos NOD , Camundongos SCID , Neovascularização Patológica , Temozolomida , Fatores de Tempo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A total of 200 women planned for labour induction were randomised to receive high-dose oxytocin (6 mU/min with similar increments every 45 min) or intermediate-dose oxytocin (3 mU/min with similar increments every 45 min). Oxytocin solution was prepared with 30 units in 500 ml saline with which the infusion rate in ml/h is numerically equal to oxytocin in mU/min. We observed that the caesarean rate (18% vs 6%, p = 0.009), contraction abnormalities (35% vs 14%, p = 0.0005) and neonatal bilirubin levels (7.99 ± 2.70 vs 6.80 ± 2.65, p = 0.002) were higher with high-dose than with intermediate-dose. The induction-delivery interval (IDI) was similar (10 h 13 min with high-dose and 11 h 5 min with intermediate-dose; p = 0.237, NS). Nulliparous women benefited more with intermediate-dose as the caesarean rate was higher with high-dose (24.6% vs 7.9%, p = 0.011). Although the caesarean rate was higher in multiparous women with high-dose oxytocin, it was statistically not significant (5.7% vs 2.7%; p = 0.609). Oxytocin regimens for labour induction are usually high-dose (4-6 mU/min) or low-dose (1-1.5 mU/min). The former is associated with more contraction abnormalities and the latter with prolonged IDI; both result in an increased caesarean rate. In order to offset these disadvantages, an intermediate- dose regimen was selected. The increment interval of 45 min was selected in accordance with the pharmacokinetics of oxytocin. We observed a lower caesarean rate when compared with the high-dose regimen, without any increase in the IDI. Hence, we propose that the intermediate-dose oxytocin regimen should be preferred to the high-dose regimen for labour induction.
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Trabalho de Parto Induzido , Ocitocina , Contração Uterina/efeitos dos fármacos , Adulto , Cesárea/métodos , Cesárea/estatística & dados numéricos , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Trabalho de Parto Induzido/efeitos adversos , Trabalho de Parto Induzido/métodos , Ocitócicos/administração & dosagem , Ocitócicos/farmacocinética , Ocitocina/administração & dosagem , Ocitocina/farmacocinética , Gravidez , Resultado da Gravidez , Resultado do TratamentoRESUMO
This prospective observational study was carried out in India among 100 women with preterm pre-labour rupture of membranes (pPROM) between 26(0/7)-33(0/7) weeks on expectant management in order to correlate early-onset neonatal sepsis (EONS) with various features of chorioamnionitis. The incidence of pPROM during the study period of 1.5 years was 7%. The mean gestation at pPROM was 30(6/7) ± 1.8 weeks and at delivery was 32(1/7) ± 1 weeks. Features of chorioamnionitis in the form of clinical, microbiological, histological or a combination of these were observed in 70/100 women. Clinical chorioamnionitis was seen in 16%, bacterial isolates were present in 30% on cervical swab and in 39% on placental membrane culture and 19% had histological chorioamnionitis. EONS was present in 23/97 (24%). Clinical chorioamnionitis (p = 0.069), bacterial isolates on cervical swab (p = 0.56) or placental membranes (p = 0.39) were not found to predict EONS; whereas histological chorioamnionitis (p = 0.002) and lower gestation at delivery (p = 0.013) were significantly associated with EONS.
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Corioamnionite/patologia , Ruptura Prematura de Membranas Fetais/epidemiologia , Ruptura Prematura de Membranas Fetais/terapia , Idade Gestacional , Sepse Neonatal/epidemiologia , Conduta Expectante , Adulto , Colo do Útero/microbiologia , Corioamnionite/microbiologia , Feminino , Humanos , Incidência , Índia/epidemiologia , Sepse Neonatal/microbiologia , Placenta/microbiologia , Gravidez , Estudos Prospectivos , Fatores de Tempo , Adulto JovemRESUMO
A case-control study was conducted in India between April 2007 and January 2008, to identify the clinical and historical risk factors associated with early onset pre-eclampsia/eclampsia (PE-E) in women attending a tertiary care hospital in North India. The study group comprised 100 women with early onset severe pre-eclampsia/eclampsia (≤34 weeks) and a control group of 100 women with mild non-proteinuric hypertension (>34 weeks). A detailed history including past, personal and family history, pregnancy outcome including delivery details and perinatal outcome and available investigations were recorded in a pre-designed proforma. Multiple logistic regression analysis was used to determine the risk factors for pre-eclampsia. The risk factors that were associated with increased risk of early onset severe PE-E were: history of PE-E in a previous pregnancy (adjusted odds ratio, aOR 71.40); exposure to passive smoking (aOR 16.40); inadequate antenatal supervision (aOR 15.21); family history of hypertension in one or more 1st-degree relative (aOR 8.92); living in a joint family (aOR 6.93); overweight (>120% to 150% of pre-pregnancy ideal body weight, aOR 4.65) and lower socioeconomic class (Kuppuswamy's class III-V) (aOR 3.00). Based on the above risk factors, a risk model can be constituted as practised in other places and implemented in the primary preventive measure of early-onset severe pre-eclampsia among the North Indian women attending this tertiary care hospital.
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Eclampsia/epidemiologia , Pré-Eclâmpsia/epidemiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Índia/epidemiologia , Gravidez , Fatores de Risco , Adulto JovemRESUMO
Cephalometric norms are used for providing guidance to clinicians during diagnosis and treatment planning. Most classical norms are not applicable to diverse racial and ethnic population hence the purpose of this study was to establish the soft tissue norms of a North Indian population group using Legan and Burstone soft tissue analysis. The study was conducted on 60 adult subjects with esthetically pleasing profiles aged 18-25 years. Standardized lateral cephalograms were taken in a natural head position and analyzed. North Indians were found to have more convex faces, protrusive lips and acute nasolabial angles compared with Caucasians. Males had more convex faces and protrusive lips than females. This North Indian population group had significant deviations from the Caucasian standards. Considerable diversity was also found for some of the soft tissue variables in males and females.
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Cefalometria/estatística & dados numéricos , Adolescente , Adulto , Benchmarking , Cefalometria/métodos , Queixo/anatomia & histologia , Etnicidade/estatística & dados numéricos , Face/anatomia & histologia , Feminino , Humanos , Índia , Lábio/anatomia & histologia , Masculino , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Nariz/anatomia & histologia , Procedimentos Cirúrgicos Ortognáticos , Valores de Referência , Fatores Sexuais , Dimensão Vertical , População Branca/estatística & dados numéricos , Adulto JovemRESUMO
In a previous study it was found that the therapeutic effects of QLT0267, a small molecule inhibitor of integrin-linked kinase (ILK), were influenced by Her2/neu expression. To understand how inhibition or silencing of ILK influences Her2/neu expression, Her2/neu signaling was evaluated in six Her2/neu-positive breast cancer cell lines (LCC6(Her2), MCF7(Her2), SKBR3, BT474, JIMT-1 and KPL-4). Treatment with QLT0267 engendered suppression (32-87%) of total Her2/neu protein in these cells. Suppression of Her2/neu was also observed following small interfering RNA-mediated silencing of ILK expression. Time course studies suggest that ILK inhibition or silencing caused transient decreases in P-AKT(ser473), which were not temporally related to Her2/neu downregulation. Attenuation of ILK activity or expression was, however, associated with decreases in YB-1 (Y-box binding protein-1) protein and transcript levels. YB-1 is a known transcriptional regulator of Her2/neu expression, and in this study it is demonstrated that inhibition of ILK activity using QLT0267 decreased YB-1 promoter activity by 50.6%. ILK inhibition was associated with changes in YB-1 localization, as reflected by localization of cytoplasmic YB-1 into stress granules. ILK inhibition also suppressed TWIST (a regulator of YB-1 expression) protein expression. To confirm the role of ILK on YB-1 and TWIST, cells were engineered to overexpress ILK. This was associated with a fourfold increase in the level of YB-1 in the nucleus, and a 2- and 1.5-fold increase in TWIST and Her2/neu protein levels, respectively. Taken together, these data indicate that ILK regulates the expression of Her2/neu through TWIST and YB-1, lending support to the use of ILK inhibitors in the treatment of aggressive Her2/neu-positive tumors.
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Proteínas de Ligação a DNA/fisiologia , Proteínas Nucleares/fisiologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Receptor ErbB-2/antagonistas & inibidores , Proteína 1 Relacionada a Twist/fisiologia , Compostos Azo/farmacologia , Proteínas de Ligação a DNA/análise , Receptores ErbB/análise , Humanos , Proteínas Nucleares/análise , Proteínas Serina-Treonina Quinases/fisiologia , Pirazóis/farmacologia , RNA Interferente Pequeno/genética , Receptor ErbB-2/análise , Fator de Transcrição STAT3/fisiologia , Transdução de Sinais , Células Tumorais Cultivadas , Proteína 1 de Ligação a Y-BoxRESUMO
In a prospective, randomised trial, 100 pregnant women with >/= one prior spontaneous pre-term birth were randomised into two groups. Group 1 women received 100 mg natural micronised progesterone intravaginally once daily from 20-24 weeks' gestation until 36 weeks. Group 2 women did not receive progesterone. Both groups were regularly supervised until delivery. Pre-term birth (<37 and <34 weeks) and other maternal, neonatal outcomes were primary and secondary outcomes, respectively. Chi-square test and Fisher exact test were used to compare categorical variables. Independent sample t-test and one-way ANOVA were used to compare continuous variables and multiple comparisons, respectively. Pre-term births <37 weeks were significantly lower in Group 1 (12% vs 38%, p = 0.002), but pre-term births <34 weeks were similar. The mean birth weight of neonates born to women in Group 1 was significantly higher (2800 vs 2,500 g, p = 0.023). We concluded intravaginal administration of 100 mg of natural micronised progesterone significantly reduced the incidence of pre-term birth <37 weeks in women with > or = one prior pre-term birth. Future research is warranted to assess the long-term safety and efficacy of progesterone.
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Nascimento Prematuro/prevenção & controle , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Administração Intravaginal , Adulto , Feminino , Humanos , Índia , Gravidez , Prevenção Secundária , Adulto JovemRESUMO
Axonal damage, demylination and inflammation of the central nervous system are the major pathological features of the human multiple sclerosis (MS). MS is thought to be due to abnormal T cell mediated immune response. Oxidative stress plays an important role in the advancement of MS. The management of oxidative stress by outlining central role of reduced glutathione. In our experiment we used Experimental autoimmune encephalomyelitis (EAE) animal model that mimic human MS and tested the effect of Thymoquinone (TQ), an oil constituent of Nigella Sativa also known as black seed. Thirty female mice of strain C57BL/6J and aged between 6 to 12 weeks were placed into 3 groups of 10 and were given Myelin Oligodendrocyte Glycoprotein (MOG) subcutaneously (SC) to induce EAE. Group A was the control group. Group B received MOG (SC) and TQ intraperiotoneally (IP) from day 1 till day 50. Group C received MOG (SC) and TQ (IP) on the appearance of first sign and symptoms of chronic relapsing EAE (CR-EAE). All Mice were examined daily for behavioral deficits and all euthanized and sacrificed on day 50. Preliminary result showed that TQ due to its antioxidant effect is almost 90% preventive and 50% curative in CR-EAE. This result could assist further studies on the mechanism of action of TQ in CR-EAE and explore the possibility of treating the human chronic relapsing multiple sclerosis phase.
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Anticonvulsivantes/uso terapêutico , Eclampsia/tratamento farmacológico , Sulfato de Magnésio/uso terapêutico , Anticonvulsivantes/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Magnésio/sangue , Sulfato de Magnésio/efeitos adversos , Gravidez , Resultado da GravidezAssuntos
Abortivos não Esteroides/efeitos adversos , Abortivos Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Mifepristona/efeitos adversos , Misoprostol/efeitos adversos , Ruptura Uterina/induzido quimicamente , Adulto , Feminino , Humanos , Gravidez , Segundo Trimestre da GravidezRESUMO
An outbreak of cholera caused by Vibrio cholerae O1 Ogawa occurred in and around Chandigarh during July 22-31, 2002. Of the 303 patients admitted to two hospitals, 82 were confirmed by culture. Two rehabilitation colonies located at the periphery of Chandigarh were mainly affected. The isolates were biotyped as Eltor and were susceptible to many antibiotics. Thirty one (35.2%) of 88 water samples showed evidence of faecal contamination. The survey of the area revealed sewage contamination of the drinking water supply. The outbreak was controlled by providing safe drinking water to the people and correcting the defects in the sewage and water pipelines.
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Cólera/epidemiologia , Surtos de Doenças , Vibrio cholerae O1 , Adolescente , Adulto , Criança , Pré-Escolar , Cólera/microbiologia , Feminino , Humanos , Índia/epidemiologia , Masculino , Vibrio cholerae O1/isolamento & purificação , Microbiologia da Água , Abastecimento de ÁguaAssuntos
Abortivos não Esteroides/uso terapêutico , Colo do Útero/diagnóstico por imagem , Metotrexato/uso terapêutico , Gravidez Ectópica/diagnóstico por imagem , Gravidez Ectópica/tratamento farmacológico , Adulto , Colo do Útero/patologia , Feminino , Humanos , Gravidez , Resultado da Gravidez , UltrassonografiaRESUMO
1. Oxygen free radicals have been suggested to be a contributory factor in complications of diabetes mellitus. There are many reports indicating the changes in parameters of oxidative stress in diabetes mellitus. In this study we aimed to identify whether oxidative stress occurs in the liver and pancreas in the initial stages of development of diabetes. 2. We therefore investigated the lipid peroxide level (thiobarbituric acid-reactive substances, TBARS) and activities of antioxidant enzymes [superoxide dismutase (SOD), catalase and glutathione peroxidase] in liver and pancreas of control and streptozotocin-induced diabetic rats at various stages of development of diabetes. 3. Male Sprague-Dawley rats were divided into two groups: group I, control (n = 42) and group II, diabetic (n = 42). Each group was further subdivided into seven groups consisting of six rats each. Rats in these subgroups were studied at weekly intervals (0 to 6 weeks). Plasma glucose levels, TBARS levels and activities of antioxidant enzymes were measured in liver and pancreas at various time intervals. 4. There was a significant (P < 0.05) and progressive increase in TBARS levels of liver and pancreas in the diabetic group. Total SOD and Cu-Zn-SOD activity increased (P < 0.05) with progression of diabetes while Mn-SOD activity showed no significant change in either tissue. Catalase and glutathione peroxidase activities increased significantly (P < 0.05) in liver and pancreas. 5. Immunohistochemical study of pancreatic islet revealed a decrease in the expression of insulin with progression of diabetes. However, glucagon and somatostatin showed an increase in immunoreactivity and a difference in their distribution pattern. 6. The findings of the present study suggest that oxidative stress starts at early onset of diabetes mellitus and increases progressively. In conclusion, the structural damage to these tissues or complications of diabetes mellitus may be due to oxidative stress.
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Diabetes Mellitus Experimental/metabolismo , Fígado/metabolismo , Estresse Oxidativo , Pâncreas/metabolismo , Animais , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de TempoRESUMO
A number of models of focal ischemia have been created to mimic acute middle cerebral artery (MCA) occlusion. In the present series of experiments, we report our observations on the thrombin model of MCA occlusion and the neuroprotective effects of intraarterial thrombolysis with two doses of urokinase (2500 and 5000 units/kg). In all experiments male Wistar rats were used and the animals were allowed to recover for 48 h before assessment of neurobehavioral performance on a four-point scale. The extent of cerebral hemispheric damage was calculated as the percentage of brain infarction using TTC staining. Occlusion of the MCA was effected by the introduction of an autologous blood clot into the internal carotid artery (ICA) approximately 2 mm from the origin of the MCA. This clot was formed by the drawing of 10 microl of blood into a bovine thrombin (20 microg per animal) containing intraarterial catheter, which was inserted into the right ECA. After standing for 15 min to allow clot formation, the catheter was advanced gently through the ICA to the site of injection. MCA occlusion produced a consistent large infarction in all animals. Urokinase infusion (i.a. ) was started 2 h after arterial occlusion in the initial series. In animals treated with low dose urokinase infusion there was mild protection. Animals treated with high dose urokinase infusion showed a highly significant improvement in the motor recovery and a decrease in the extent of infarction compared to control animals. In the final group, the infusion of urokinase was delayed for 3 h. While producing protection in some animals, it also produced intracerebral hemorrhage in two of eight animals. Thus delay of infusion to 180 min increased the risk of hemorrhage. This model may in the future be used to test the protective effects of combination therapy with thrombolysis and neuroprotective medications.
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Isquemia Encefálica/tratamento farmacológico , Infarto Cerebral/tratamento farmacológico , Embolia e Trombose Intracraniana/tratamento farmacológico , Ativadores de Plasminogênio/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/farmacologia , Animais , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/patologia , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Isquemia Encefálica/patologia , Infarto Cerebral/patologia , Modelos Animais de Doenças , Injeções Intra-Arteriais , Embolia e Trombose Intracraniana/patologia , Masculino , Exame Neurológico , Ratos , Ratos Wistar , TrombinaRESUMO
We investigated the effect of hemorrhagic shock and reinfusion on the cardiac function and contractility, plasma CK and CK-MB activity and lactate concentration, oxyradical-producing activity of polymorphonuclear leukocytes (PMNL-CL), cardiac chemiluminescence (LV-CL), antioxidant enzyme activity [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX)] and malondialdehyde (MDA) concentration in anesthetized dogs to determine the role of oxyradicals in cardiac depression and cellular injury in hemorrhagic shock and reinfusion. The dogs were assigned into three groups: I (sham), 4 h duration; II (S + R), 2 h of shock followed by reinfusion for 2 h; III (SOD + S + R), as II but pretreated with PEG-SOD. Hemorrhagic shock was produced by withdrawal of blood to maintain the mean arterial pressure at 50 +/- 5 mm Hg. Cardiac function and contractility were depressed during hemorrhagic shock. Plasma CK, CK-MB and lactate increased during shock. Following reinfusion after 2 h of shock hemodynamic parameters and plasma lactate tended to return towards control values. Plasma CK and CK-MB, PMNL-CL and cardiac MDA, total-, Mn- and CuZn-SOD activity increased while LV-CL decreased. In spite of the increase in the antioxidant reserve, there was oxidative damage. Pretreatment with SOD attenuated the deleterious effects of shock and reinfusion on the cardiovascular function, plasma CK, and CK-MB, PMNL-CL, cardiac MDA, SOD, and LV-CL. Protection was incomplete for cardiovascular function and plasma CK and CK-MB. These results suggest that oxyradicals may partly be involved in the deterioration of cardiovascular function and cellular injury during hemorrhagic shock and reinfusion.
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Ácido Láctico/sangue , Oxirredutases/metabolismo , Choque Hemorrágico/fisiopatologia , Animais , Catalase/metabolismo , Creatina Quinase/sangue , Cães , Feminino , Radicais Livres/farmacologia , Glutationa Peroxidase/metabolismo , Hemodinâmica , Medições Luminescentes , Masculino , Malondialdeído/metabolismo , Neutrófilos , Artéria Pulmonar/fisiologia , Pressão Propulsora Pulmonar/fisiologia , Choque Hemorrágico/sangue , Volume Sistólico/fisiologia , Superóxido Dismutase/metabolismo , Função VentricularRESUMO
Oxygen free radicals (OFRs) have been suggested to be a contributory factor in complications of diabetes mellitus. In the present study, we investigated the lipid peroxide level measured as thiobarbituric acid reactive substances (TBARS) and activities of antioxidant enzymes viz., [superoxide dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GSH-Px)] in the kidney of streptozotocin induced diabetic rats at various stages of development of diabetes. Sprague Dawley rats were divided into two groups: group I, control (n = 42) and group II, diabetic (n = 42). Each group was further subdivided into seven groups each consisting of six rats. Rats in subgroups were studied at weekly intervals (0 to 6 weeks). Blood glucose levels were estimated at the time of sacrifice. TBARS levels and activity of antioxidant enzymes were measured in kidney. The levels of TBARS in the diabetic group increased initially, dropped to baseline level after 2 weeks and then progressively increased at 5th and 6th week (p < 0.05). There was an increase in catalase activity at first week after that it decreased as compared to control group. However, GSH-Px activity in the diabetic group increased after 1 week and then remained at the same level except a small drop in the 2nd week. Total SOD and CuZn-SOD activity increased significantly in diabetic kidney as compared to controls at all time intervals, while Mn-SOD activity showed no change. The present findings suggest that oxidative stress accompanies at early onset of diabetes mellitus and the susceptibility of the kidney to oxidative stress during the early stages may be an important factor in the development of diabetic nephropathy.
Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Experimental/metabolismo , Rim/metabolismo , Animais , Glicemia/metabolismo , Catalase/metabolismo , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/etiologia , Glutationa Peroxidase/metabolismo , Rim/enzimologia , Rim/patologia , Peróxidos Lipídicos/metabolismo , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de TempoRESUMO
BACKGROUND: Investigations of the effects of high cholesterol diet in the presence and absence of garlic on the genesis of atherosclerosis, the blood lipid profile, aortic tissue lipid peroxidation product malondialdehyde, chemiluminescence, a marker for antioxidant reserve and activity of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase were made in rabbits. METHODS AND RESULTS: Four groups of 10 rabbits each were studied: group 1 was given regular rabbit chow, group 2 was given rabbit chow diet supplemented with garlic powder (300 mg twice daily orally), group 3 was given 1% cholesterol diet, group 4 was given 1% cholesterol diet supplemented with garlic powder (300 mg twice daily orally). Blood concentration of triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol were measured before and after 4 and 10 weeks of experimental diets. The aorta was removed at the end of protocol (10 weeks) for assessment of atherosclerotic changes (gross and microscopic), malondialdehyde concentration, chemiluminescence, and activity of antioxidant enzymes. Total cholesterol, low density-lipoprotein cholesterol and ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol and ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol increaserd in group 3 and 4; the increase was smaller in group 4 than in in group 3 although not significant. Serum high-density lipoprotein cholesterol decreased to a similar extent in groups 3 and 4. Serum triglyceride and very low-density lipoprotein cholesterol remained unchanged in group 3 but increased in group 4. These values were significantly higher than those in group 1. Garlic in rabbits with control diet decreased the levels of triglyceride and very low density lipoprotein but did not affect the levels of total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol and the ratio of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol. There was an increase in aortic tissue malondialdehyde, chemiluminescence, and activities of catalase and glutathione peroxidase in group 3 compared with those in group 1. Levels of aortic malondialdehyde, chemiluminescence, catalase, and glutathione peroxidase were lower in group 4 compared with group 3; however, values for malondialdehyde and chemiluminescence were lower and that of catalase and glutathione peroxidase were higher in group 4 compared with group 1. Superoxide dismutase activity was similar in all the four groups. Malondialdehyde, chemiluminescence, and activity of catalase of aortic tissue decreased while activity of glutathione peroxidase increased in group 2. Atherosclerotic changes were lower in group 4 compared with group 3. Histologic changes were practically similar in groups 3 and 4. CONCLUSIONS: Increased levels of malondialdehyde, chemiluminescence, and antioxidant enzymes associated with development of atherosclerosis suggests a role for oxygen free radicals in the pathogenesis of hypercholesterolemic atherosclerosis. The protection afforded by garlic was associated with decrease in aortic malondialdehyde and chemiluminescence inspite of no change in serum cholesterol. These findings suggest that oxygen free radicals are involved in the genesis and maintenance of hypercholesterolemic atherosclerosis and that use of garlic can be useful in preventing the development of hypercholesterolemic atherosclerosis.
RESUMO
1. Oxygen free radicals have been suggested to be a contributory factor in complications of diabetes mellitus. In the present study, we investigated the lipid peroxide level [thiobarbituric acid-reactive substances (TBARS)] and activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) in aorta, heart and blood of control and streptozotocin-induced diabetic rats at various stages of development of diabetes (0 to 6 weeks). 2. There was no change in the TBARS levels of aorta, heart and blood in the control group. A significant (P < 0.05) increase in TBARS levels of aorta, heart and blood was observed in the diabetic group. 3. There were no significant changes in the activities of superoxide dismutase, catalase and glutathione peroxidase in the aorta, heart and blood of control rats at all time intervals. In the diabetic group, there was a significant (P < 0.05) increase in the activity of superoxide dismutase and glutathione peroxidase in aorta from the fourth week onwards while the activity of catalase increased at all time intervals. In the heart of diabetic rats, the activity of total superoxide dismutase and Cu-Zn-superoxide dismutase increased significantly (P < 0.05) from the second week onwards while activity of Mn-superoxide dismutase decreased at the fourth week and increased at the sixth week. The activity of catalase and glutathione peroxidase increased significantly (P < 0.05) at all time intervals. In the blood, the activity of superoxide dismutase and glutathione peroxidase increased from the third week while catalase activity increased from the fourth week. 4. The present findings suggest that oxidative stress starts at early onset of diabetes mellitus and increases progressively.