RESUMO
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.
Assuntos
Competência Clínica , Educação Baseada em Competências , Currículo , Avaliação Educacional/normas , Feedback Formativo , Educação de Pós-Graduação em Medicina , Humanos , ÍndiaRESUMO
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.
Assuntos
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.
Assuntos
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.
Assuntos
Eclampsia/epidemiologia , Pré-Eclâmpsia/epidemiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Índia/epidemiologia , Gravidez , Fatores de Risco , Adulto JovemRESUMO
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.
Assuntos
Nascimento Prematuro/prevenção & controle , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Administração Intravaginal , Adulto , Feminino , Humanos , Índia , Gravidez , Prevenção Secundária , Adulto JovemRESUMO
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.
RESUMO
Fifteen patients with advanced or recurrent squamous-cell carcinoma of the cervix, vulva, vagina, and urethra were treated with simultaneous combination chemotherapy (5-fluorouracil infusion and mitomycin C) and radiotherapy (3,000 rad for a period of three weeks). Three to four weeks after completion of radiotherapy, 13 of 15 patients achieved partial or complete tumor shrinkage. Nine of 15 patients are alive, eight of whom (at a median follow-up time of 24 months) have no evidence of disease. The longest survival time was 45 + months. There was minimal toxicity associated with this therapy. The results of this pilot study suggest that the simultaneous administration of radiation and chemotherapy is an effective method of treatment of advanced female genital tract carcinoma.
Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias dos Genitais Femininos/terapia , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/mortalidade , Radioisótopos de Cobalto/uso terapêutico , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Neoplasias dos Genitais Femininos/mortalidade , Humanos , Pessoa de Meia-Idade , Mitomicina , Mitomicinas/administração & dosagem , Projetos Piloto , Teleterapia por Radioisótopo , Fatores de TempoRESUMO
Amonafide is a new imide derivative of naphthalic acid. The drug had demonstrated significant activity in preclinical studies and some activity in Phase I trials. The drug is extensively metabolized and detected in plasma and urine. Its toxicity has previously been correlated to the formation of an active metabolite, N-acetyl-amonafide. Amonafide was chosen for inclusion in the Cancer and Leukemia Group B (CALGB) master metastatic breast cancer protocol. CALGB 8642 randomizes previously untreated metastatic breast cancer patients either to one of several Phase II agents given for up to four cycles and then followed by standard cyclophosphamide-doxorubicin-5-fluorouracil, or to immediate treatment with standard cyclophosphamide-doxorubicin-5-fluorouracil. The end point of CALGB 8642 is to assess the difference in survival, toxicity, and overall response when limited exposure to Phase II agents precedes standard chemotherapy. This report deals only with amonafide as a Phase II agent. Comparisons with the cyclophosphamide-doxorubicin-5-fluorouracil arm will not be addressed. Patients had to have histologically documented measurable breast cancer and a performance status of 0-1. Patients could not have had prior chemotherapy for metastatic disease. Prior adjuvant chemotherapy was permitted. Patients could not have visceral crisis. Amonafide was given at 300 mg/m2/day i.v. for 5 days, and repeated at 21-day intervals for a maximum of four cycles. Escalation and reduction in dose was mandated dependent on hematotoxicity or lack thereof. Toxicity was primarily hematological and bimodal: 32% had grade 3 or 4 leukopenia and 24% had grade 3 or 4 thrombocytopenia; 22% had no leukopenia and 44% had no thrombocytopenia. The response rate was 18%, including one complete response. When response was analyzed by hematological toxicity, there was a 35.7% response if patients had leukopenia grade 3/4 (versus 8.3%, P = 0.08). There was a 50% response if patients had thrombocytopenia grade 3/4 (versus 7.1%, P = <0.01). We conclude that amonafide is somewhat active in previously untreated breast cancer patients. There may be a steep dose-response curve, based on the significant correlation between myelosuppression and response. Rates of responses in patients adequately dosed (i.e., with significant hematotoxicity) with amonafide ranged from 35 to 50%. Further studies will incorporate individualized dosing based on pretreatment acetylator phenotyping.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Imidas/uso terapêutico , Isoquinolinas/uso terapêutico , Adenina , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Imidas/administração & dosagem , Imidas/efeitos adversos , Isoquinolinas/administração & dosagem , Isoquinolinas/efeitos adversos , Menopausa , Pessoa de Meia-Idade , Naftalimidas , Metástase Neoplásica , Organofosfonatos , Receptores de Estrogênio/análiseRESUMO
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.
Assuntos
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
Two healthy subjects took 3H-digoxigenin-12 alpha and unlabeled digoxigenin. Metabolites were assayed by high-pressure liquid chromatography (HPLC) in serum and urine. Of the tritium activity in the serum at 30 min, less than 26% chromatographed with digoxigenin; the rest chromatographed as metabolites, most of which were polar. The main polar metabolites identified were glucuronides of 3-epidigoxigenin. An important route of biotransformation to polar metabolites appears to be from 3 beta-digoxigenin through 3-keto-digoxigenin to 3-epidigoxigenin. Several HPLC peaks remain unidentified. There was extensive cross reactivity between metabolites and antisera to digoxin. The digoxigenin route of digoxin biotransformation to polar metabolites may be important in some patients receiving digoxin and such metabolites could contribute an important fraction to the serum digoxin concentration measured by radioimmunoassay.
Assuntos
Digoxigenina/metabolismo , Digoxina/análogos & derivados , Biotransformação , Cromatografia Líquida de Alta Pressão , Digoxigenina/sangue , Digoxigenina/urina , Humanos , Masculino , RadioimunoensaioRESUMO
3H-digoxin-12 alpha and unlabeled digoxin were administered down a nasogastric tube and digoxin, digoxyigenin and its mono- and bis-digitoxosides, and pH were assayed in gastric fluid of 6 healthy subjects at intervals for 90 min each under 4 conditions: pentagastrin infusion 6 micrograms/kg/hr with the subjects ambulatory and supine, and saline infusion ambulatory and supine. Intragastric hydrolysis occurred at roughly the same rate as reported in vitro. At 90 min, an average of 12.5% of the radioactivity that remained in the gastric fluid was recovered as digoxin for the 2 conditions when pentagastrin was infused, compared with 52.5% for th 2 conditions when saline was infused. The main glycosidic metabolite was digoxigenin and the amount correlated closely with the hydrogen ion activity in gastric fluid at 90 min (r = 0.83, p less than 0.01). Only minor differences were found between the supine and ambulatory conditions. The clinical significance of these results remains to be determined.
Assuntos
Digoxina/metabolismo , Suco Gástrico/análise , Biotransformação/efeitos dos fármacos , Glicosídeos Digitálicos/análise , Digoxigenina/análise , Digoxina/análise , Feminino , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Masculino , Pentagastrina , Postura , Cloreto de Sódio/administração & dosagemRESUMO
High-performance liquid chromatography (HPLC) analysis was performed on methylene chloride extracts of urine from six subjects after administration of 3H-digoxin-12 alpha and unlabeled digoxin by nasogastric tube under four conditions: pentagastrin and control saline infusions, each in the supine and ambulatory states. There were no differences with change in position. With pentagastrin stimulation of acid secretion, there was extensive intragastric hydrolysis, mainly to digoxigenin; there was further extensive biotransformation leading to an increase in both extractable and unextractable metabolites in urine, particularly the latter. In the first 5 hr mean digoxin was only 17% and unextractable metabolites were 54% of total urine radioactivity. Extractable radioactivity was found under HPLC peaks with retention times of digoxin, digoxigenin, and its mono- and bis-digitoxosides. There were also three other peaks that were not identified; two correlated with gastric H+ activity and with the peak for digoxigenin, which is probably their precursor since similar peaks were found after ingestion of digoxigenin. The third unidentified peak eluted immediately after the digoxin, with which it correlated; it may have a close structural relationship to digoxin. Gastric acid stimulation induced a major increase in the production of urinary metabolites and may prove a useful model for the study of digoxin biotransformation, which is not yet well defined.
Assuntos
Digoxina/metabolismo , Mucosa Gástrica/metabolismo , Biotransformação , Cromatografia Líquida de Alta Pressão , Digoxina/análogos & derivados , Digoxina/urina , Suco Gástrico , Concentração de Íons de HidrogênioRESUMO
The underlying mechanism for severe damage with repetitive ischemia is not fully understood. Because of prolonged periods of reperfusions between the brief insults, we speculated that the severe damage may be secondary to excessive generation of oxygen free radicals. In this study we tested the efficacy of peg-superoxide dismutase (SOD) in a model of repeated ischemia in gerbils. Superoxide dismutase (SOD) or vehicle (saline) was delivered through osmotic pumps into the lateral ventricles continuously from the onset of the insult until the gerbils were sacrificed 6 days later. Three doses of SOD were used in the experiments (110, 150, and 190 units per microliter). Damage was assessed using a 0-4 point scoring system and statistical comparisons were done using the Mann-Whitney U-test. There was significant protection in the hippocampus (p < 0.05), striatum (p < 0.001), and substantia nigra reticulata (p < 0.05) in the lowest dose SOD-treated group (110 units per microliter). Animals treated with 150 units showed lesser (but significant) protection in the thalamus, medial geniculate nucleus, and striatum. In the animals treated with the higher dose of SOD (190 units per microliter), the extent of damage was no different than vehicle-treated controls in the cortex, striatum, and hippocampus. Compared to controls, neuronal damage was, however, significantly more severe in the medial geniculate nucleus and the thalamus in the high-dose SOD-treated animals (p < 0.05). Our experiments suggest that the SOD may have a small therapeutic window. Higher doses may either have no neuroprotective effects or may be harmful.
Assuntos
Encéfalo/patologia , Sequestradores de Radicais Livres/farmacologia , Ataque Isquêmico Transitório/prevenção & controle , Neurônios/patologia , Polietilenoglicóis/farmacologia , Superóxido Dismutase/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/patologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Relação Dose-Resposta a Droga , Radicais Livres , Corpos Geniculados/efeitos dos fármacos , Corpos Geniculados/patologia , Gerbillinae , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Ataque Isquêmico Transitório/patologia , Masculino , Neurônios/efeitos dos fármacos , Especificidade de Órgãos , Polietilenoglicóis/administração & dosagem , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Superóxido Dismutase/administração & dosagem , Tálamo/efeitos dos fármacos , Tálamo/patologiaRESUMO
We investigated the effects of high cholesterol diet in the absence and presence of vitamin E on the activity of antioxidant enzymes [superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px)] in rabbits. The animals were divided into 4 groups each comprising of 10 rabbits. Group I, regular rabbit chow diet; Group II, regular rabbit chow diet with added vitamin E; Group III, high cholesterol diet; and Group IV, high cholesterol diet+vitamin E. Antioxidant enzymes of blood were measured in each group before and after 1, 2, 3, and 4 months on the experimental diets. The aorta was removed at the end of the protocol for measurement of antioxidant enzymes. There was a decrease in activity of SOD and GSH-Px and an increase in activity of catalase in blood of Group III. Vitamin E produced a decrease in blood SOD, catalase and GSH-Px activity in Group II and prevented the decrease in SOD and GSH-Px activity in Group IV but did not affect the changes in the catalase activity. SOD, catalase and GSH-Px activity of aortae from Group III increased significantly, while catalase activity increased and GSH-Px activity decreased in those from Group II. Vitamin E prevented the cholesterol-induced rise in catalase and GSH-Px activity in aorta but did not prevent the rise in SOD activity. These results suggest that the activity of antioxidant enzymes in blood is affected differently from that in aortic tissue. There appears to be a mutually supportive interaction among the antioxidant enzymes which provide defense against oxidant injury. The protective effects of vitamin E against hypercholesterolemic atherosclerosis may not be due to changes in the antioxidant enzymes but may be mainly mediated through its chain-breaking antioxidant activity.
Assuntos
Antioxidantes/metabolismo , Hipercolesterolemia/enzimologia , Vitamina E/farmacologia , Animais , Aorta/enzimologia , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Coelhos , Superóxido Dismutase/metabolismoRESUMO
Responsiveness to recall antigens by memory and naive T helper cells is different. To study whether such a difference is also applicable to affinity for allorecognition, we analyzed the effect of an IgG MLR blocking antibody separated from sera of patients with known kidney transplant chronic rejection on primed and unprimed CD4+ T cell alloreactivity. The results show that addition of the IgG fraction inhibits the patient's own unprimed T helper cell responses to a panel of four different alloantigens as well as a third-party mixed lymphocyte response. The same IgG fraction inhibited third-party naive T helper cell, but not autologous unprimed T helper cell, proliferation to adherent anti-CD3 antibody, which suggests that the mechanism of inhibitory action of the IgG is allogeneic-dependent. This IgG also did not induce inhibition of any of the T helper cell clone responsiveness, raised from the same or other patients, when stimulated with the same alloantigens used for unprimed cell alloactivation. Differential responses of naive and memory CD4+ T cells to alloantigens may explain some differences between the in vivo and in vitro systems and why allograft rejection can proceed in the presence of allogeneic blocking antibodies.
Assuntos
Rejeição de Enxerto , Imunoglobulina G/imunologia , Memória Imunológica , Isoantígenos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Sequência de Bases , Ligação Competitiva , Células Clonais , Humanos , Transplante de Rim/imunologia , Teste de Cultura Mista de Linfócitos , Dados de Sequência Molecular , Transplante HomólogoRESUMO
We report the case of a seventy-four-year-old woman with advanced squamous cell carcinoma of the urethra who achieved complete biopsy-proved regression of the tumor for more than thirty months after therapy with 5-fluorouracil, mitomycin-C, and radiotherapy.
Assuntos
Carcinoma de Células Escamosas/terapia , Radioisótopos de Cobalto/uso terapêutico , Fluoruracila/uso terapêutico , Mitomicinas/uso terapêutico , Neoplasias Uretrais/terapia , Idoso , Biópsia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Infusões Parenterais , Mitomicina , Mitomicinas/administração & dosagem , Fatores de Tempo , Neoplasias Uretrais/patologia , Neoplasias Uretrais/radioterapiaRESUMO
A unique case of a collision tumor of the kidney composed of a renal cell carcinoma and a squamous cell carcinoma is reported. Although a few cases of combined tumors of the kidney have been reported previously, we were unable to find any similar case in the literature. Squamous cell carcinoma of the kidney usually behaves aggressively. Early diagnosis and surgical treatment before the tumor has extended beyond the capsule offer the best hope of cure.
Assuntos
Carcinoma de Células Renais/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Renais/patologia , Rim/patologia , Neoplasias Primárias Múltiplas/patologia , Idoso , Humanos , MasculinoRESUMO
Repetitive cerebral ischemia results in severe neuronal damage in multiple regions of the brain including the hippocampus, striatum, thalamus, medial geniculate nucleus and the substantia nigra reticulata (SNr). We postulated that the damage in the SNr was delayed, resulting from a loss of striatal inhibitory input. We used the gerbil model of repetitive ischemia (3 min times 2 and 3 min times 3) to evaluate the extent of neuronal damage at 2, 3, 5 and 7 days after the ischemic insult. Silver degeneration stain was used for histological evaluation. Our results indicate that damage in the SNr begins after 48 h and is maximum at 7 days. This delay in onset of damage offers a window for pharmacological protection.
Assuntos
Ataque Isquêmico Transitório/patologia , Degeneração Neural/fisiologia , Neurônios/patologia , Prosencéfalo/irrigação sanguínea , Substância Negra/patologia , Animais , Gerbillinae , Masculino , Substância Negra/citologia , Fatores de TempoRESUMO
GABAergic inhibitory mechanisms may offer protection to neurons after global ischemia. We tested the effects of gamma-vinyl GABA, a GABA-transaminase inhibitor, via continuous infusion in the third ventricle (Alza pumps) in a gerbil model of repetitive forebrain ischemia. We used two episodes of 3 min duration with a 'reperfusion' interval of 1 h between the insults. Histological analysis was done with silver staining 5 days after the insult. Our results show that there is significant protection of the hippocampus CA1 region and substantia nigra reticulata in treated animals compared to controls. An increase in GABA levels, decrease in glutamate, or mild hypothermia, may be potential mechanisms for this protection. GABAergic agents may prove useful agents in repetitive ischemia.
Assuntos
4-Aminobutirato Transaminase/antagonistas & inibidores , Aminocaproatos/administração & dosagem , Hipocampo/efeitos dos fármacos , Ataque Isquêmico Transitório/fisiopatologia , Prosencéfalo/irrigação sanguínea , Substância Negra/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Ventrículos Cerebrais , Gerbillinae , Hipocampo/patologia , Bombas de Infusão , Ataque Isquêmico Transitório/patologia , Masculino , Substância Negra/patologia , VigabatrinaRESUMO
The present investigation deals with the in vivo effects of oxygen free radicals (OFRs) in the absence and presence of scavengers of OFRs (superoxide dismutase, SOD, and catalase) on the cardiac function and contractility and with the in vitro effects of exogenous OFRs and various pH and pO2 on the release of acid hydrolases from dog myocardial lysosomes. The hemodynamic measurements were made before and at various intervals after administration of OFRs for up to 2 h. Xanthine plus xanthine oxidase (X-XO) and opsonized zymosan were used to generate OFRs. Oxygen free radicals produced a decrease in the cardiac function and indices of myocardial contractility. SOD alone or in combination with catalase tended to protect the cardiac function against the deleterious effects of OFRs. There was about a threefold increase in the release of cathepsin D activity in vitro from the lysosomes in the preparations treated with X-XO as compared to those without such treatment. The presence of SOD prevented the release of cathepsin D from the lysosomes. The changes in pH (4.5, 5.5, 6.0, 6.5, 7.4, 8.0) alone did not cause any increase in the enzyme release. However, the presence of OFRs at each pH resulted in a similar increase (about threefold) in the release of cathepsin D. Similarly the changes in pO2 alone did not cause the release of cathepsin D, but there were marked increases in the release of cathepsin D at each pO2 in the presence of OFRs. These data indicate that it is the oxygen free radicals and not the alterations in pH or pO2 that are primarily responsible for the release of lysosomal hydrolases.(ABSTRACT TRUNCATED AT 250 WORDS)