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1.
J Educ Health Promot ; 10: 292, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34667792

RESUMO

BACKGROUND: Postgraduate medical curriculum is usually devoted to developing competencies in the specialty concerned, patient care, and submitting dissertations. The need to impart teaching skills during postgraduation has gone unnoticed, hence Ramachandra Annual Postgraduate Teaching Skills (RAPTS), a teaching skills workshop, was conceptualized and implemented as postgraduate students serve as tutors/residents in the department to teach undergraduate medical students. This study is aimed to evaluate the effectiveness of the teaching skills workshop for postgraduates. MATERIALS AND METHODS: One hundred and seventy-eight postgraduate students of pre- and paraclinical department underwent the training in medical education principles and participated in the feedback. RAPTS Workshop was implemented as per the six-step approach. The learning was evaluated through a pre- and posttest scores. Student feedback was also obtained on the process overall objectives and contents of the workshop. Force-field analysis was performed. RESULTS: There was a significant learning by the postgraduates on various medical education principles as evidenced by significant improvement in the posttest scores (P < 0.05). Feedback regarding the general aspects of the workshop showed that 92% of the participants felt that the contents of the workshop suited their learning. Eighty-four percent of the participants opined that the presentations of the sessions were good and 91% felt that time management was good. Force-field analysis indicated that the factors favoring teaching skills workshop were higher. CONCLUSION: This study has highlighted the importance of including teaching methodology training in the postgraduate curriculum that helps in grooming the future teachers in the right direction, in the right time. Competencies related to teaching skills based on medical education principles can be included in the postgraduate curriculum.

2.
Med J Armed Forces India ; 77(Suppl 1): S57-S64, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33612933

RESUMO

Background: Medical Council of India, introduced the Post Graduate (PG) curriculum as 'Competency Based Medical Education' (CBME). Feedback from the end users is a vital step in curriculum evaluation. Therefore, the primary objective of this study was to develop and validate a Structured Feedback Questionnaire (SFQ) for postgraduates, encompassing all the components of the PG-CBME curriculum. Methods: SFQ was developed with 23 Likert based questions and four open ended questions. Content validation was done by Lawshe method. After getting institutional ethics clearance and informed consent, SFQ was administered to 121 final year PGs (response rate 100%). We performed Principal component analysis (PCA), Structural equation modeling (SEM), Chi squared test (χ2/df); goodness-of-fit index (GFI); adjusted GFI; comparative fit index (CFI) and root mean square error of approximation (RMSEA). Cronbach's alpha was done for estimating the internal consistency. Results: The validation resulted in a three-factor model comprising of "curriculum" (42.1%), "assessment" (28%), and "support" (18.5%). Chi squared test (χ2/df ratio) < 2, CFI (0.78), GFI (0.72) and RMSEA (0.09) indicated superior goodness of fit for the three-factor model for the sample data. All the extracted factors had good internal consistency of ≥0.9. Conclusion: We believe that this 23 item SFQ is a valid and reliable tool which can be utilized for curriculum evaluation and thereby formulating recommendations to modify the existing curriculum wherever required, facilitating enriched program outcomes.

3.
Curr Pharm Biotechnol ; 22(5): 706-717, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33208066

RESUMO

BACKGROUND: Cardiovascular Diseases (CVDs) such as stroke, high blood pressure, peripheral vascular disease, ischemic heart disease and acute myocardial infarction are some of the leading causes of death. To treat CVDs, commercially available thrombolytic agents are widely used. However, these thrombolytic agents have various side effects. Alternatively, fibrinolytic enzymes from bacterial sources are highly safe and have direct blood clot lytic activity. METHODS: A fibrinolytic enzyme producing bacterial strain, Bacillus flexus BF12, was isolated from a solar saltpan in Kanyakumari District, Tamilnadu, India. Enzyme production was improved by optimizing physical factors and nutritional factors. RESULTS: A novel fibrinolytic enzyme was isolated from a strain of the studied B. flexus BF12. Enzyme production was enhanced significantly by optimizing process parameters. The critical physical factors (pH and salinity) and influencing nutritional factors (carbon, nitrogen and ions) were optimized by one variable at a time approach, followed by the statistical method. The strain BF12 was highly active at alkaline pH (>7.0) and between 4 and 6% NaCl concentration. The nutrients such as fructose (carbon source), beef extract (nitrogen source) and CaCl2 significantly influenced enzyme production. Central composite design and response surface methodology improved 3.2-fold enzyme yield than unoptimized culture medium. Fibrinolytic protease was purified by ammonium sulphate precipitation, dialysis and gel filtration chromatography. DISCUSSION: The molecular weight of an enzyme was found to be 23 kDa. It was active at a broad temperature (40-60 °C) and pH (7.0-9.0) ranges. Enzyme activity was enhanced by Ca2+ and Co2+ ions. The purified protease retained 100% enzyme activity in the presence of ethanol and acetone. Acetonitrile, butanol, DMSO, methanol and chloroform showed enzyme activity of 63%, 92.5%, 94.7%, 92.3% and 90.4%, respectively. The purified enzyme degraded 100% of human blood clot. CONCLUSION: The Bacillus flexus BF12 fibrinolytic enzyme shows promising potentials in nutraceutical and food fortification applications. The application of fibrinolytic enzymes could prevent CVDs.


Assuntos
Bacillus/metabolismo , Fibrinolíticos/química , Inibidores de Serino Proteinase/biossíntese , Meios de Cultura , Humanos , Concentração de Íons de Hidrogênio , Índia , Peso Molecular , Inibidores de Serino Proteinase/química
4.
Saudi J Biol Sci ; 27(6): 1475-1481, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32489283

RESUMO

Various metabolites exist in the medicinal plants have lot of potential to cure various diseases and disorders. Plants such as, Vetiveria zizanioides, Trichosanthes cucumerina, and Mollugo cerviana were collected from Western Ghats, Tamilnadu, India. Phytochemicals were extracted from these plants using various organic solvents and tested against Gram-positive and Gram-negative bacteria. The phytochemicals such as, carbohydrate, alkaloids, steroids, saponins, flavonoids and tannin were detected from these medicinal plants. Among the extracts, methanol showed potent activity and this solvent was used to extract polyherbal medicinal plants. Methanol extract of V. zizanioides was found to be highly active against E. coli (27 ± 2 mm), P. mirabilis (19 ± 3 mm) and B. subtilis (18 ± 2 mm). Ethyl acetate extract showed high activity against E. coli (24 ± 2 mm), P. mirabilis (22 ± 3 mm) and B. subtilis (20 ± 1 mm). These three plants were taken at 1:1:1 ratio and extracted with methanol at 1:10 ratio and synergistic activity was tested against bacterial pathogens. Synergistic activity of polyherbal extract was analyzed. The extracted crude herbal medicine was found to be effective against Staphylococcus aureus, E. coli, Enterbacter sp., Pseudomonas aeruginosa, Bacillus subtilis and Proteus mirabilis. The zone of inhibition was 33 ± 3 mm, 17 ± 2 mm, 22 ± 2 mm, 40 ± 2 mm, 33 ± 1 mm and 38 ± 2 mm zone of inhibition against E. coli, S. aureus, P. aeruginosa, P. mirabilis, B. subtilis and Enterobacter sp. Polyherbal extract was found to be highly effective against P. mirabilis and Enterobacter sp. MIC values of polyherbal extract ranged from 29 ± 2.5 µg/ml to 34 ± 2.5 µg/ml. MIC value was found to be less against P. mirabilis and was high against S. aureus. Antioxidant property varied between 49 ± 3% and 95.3 ± 2%. At 20 µg/ml antioxidant activity was reported as 49 ± 3% and it was increased at higher concentrations of polyherbal extract. Two cell lines (HeLa and MCF cell lines) were selected to analyze cytotoxic activity of polyherbal extract. The methanol extract of polyherbal fraction showed cytotoxicity against these two cell lines. The LC50 value was 467 ± 2.9 µg/ml against HeLa cell line and >800 µg/ml against MCF-7 cell lines. The polyherbal extract showed antibacterial, antioxidant and anticancer activities.

5.
Saudi J Biol Sci ; 27(1): 441-447, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31889868

RESUMO

Extensive application of pesticide in agricultural field affects the enzymatic activity of non-target animals, including fishes. In this study, the impact of sublethal concentration of fenvalerate on marker enzymes of freshwater Zebra fish was evaluated. Pesticide-induced stress can specifically affect non target fishes, through elevated level of reactive oxygen species which is responsible for biochemical, cell metabolism and physiological activities. The oxidative stress mediated by fenvalerate at sub lethal concentrations after 28 days of exposure of Zebra fish. Following 28 days of exposure of pesticide, catalase, superoxide dismutase, aspartate amino transferases, alanine amino transferase, alkaline phosphatase and acid phosphatase were assessed. Results revealed reduction of superoxide dismutase activity after 28 days of exposure in sub lethal concentration of fenvalerate in liver and gills. In liver, catalase activity was found to be less in fenvalerate exposed fish than control fish. In liver, increase of 75.75% aspartate amino transferase and 38% increase in alanine amino transferase in gills. SGPT activity was relatively higher than SGOT suggests more contribution of phyruvalate than oxaloacetate formation. Fenvalerate induced changes in acid phosphatase and alkaline phosphatase activity in the liver and gills of Zebra fish after four weeks of exposure. Fenvalerate induced expression of various stress proteins in gill, liver, followed by muscle. Some proteins lost its intensity due to fenvalerate toxicity. Result revealed that enzyme assays and SDS-PAGE analysis for protein subunits determination is relevant tool to monitor stress in freshwater ecosystem. The findings suggest that in monitoring fenvalerate toxicity programme, enzyme activities can be potent diagnostic tool for fenvalerate induced toxicity.

6.
Saudi J Biol Sci ; 26(6): 1129-1133, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31516340

RESUMO

This study aimed to determine the phytochemical components, microbial inhibitory effectiveness and antioxidant properties of Aerva lanata plant extracts. The whole plant showed various medicinal applications in folklore and traditional medicine in various parts of the world. The organic extracts such as ethanol, ethyl acetate, chloroform, acetone, water and methanol were subjected for various phytochemical analysis and confirmed for the existence of flavonoids, glycosides, terpenoids and alkaloid containing components. Alternatively, the extracts were performed for the antibacterial activities against the microbial pathogens and antioxidant properties. Results indicated that, the solvent extracts showed prominent activity against the tested strains. The MIC concentrations of plant were detected from 5 mg/ml to 40 mg/ml. The plant extract was highly effective against E. coli and E. aerogenes and the MIC was 5 mg/ml. In addition, the extracts noted promising antioxidant activities. The antioxidant activities were dose dependent manner. In conclusion, A. lanata extracts showed that significant major phytochemicals and effective antioxidant and anti-microbial properties.

7.
Malays Orthop J ; 13(2): 20-27, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31467647

RESUMO

Introduction: The key important factor influencing the outcomes following rehabilitation is the surgical approach involved in Total Knee Replacement (TKR). Most studies have analysed the functional outcome in comparing the approaches on surgical perspective rather on post-operative therapeutic interventions. The current study was to analyse the effects of structured TKR rehabilitation programme on the quality of life and joint specific outcomes between two different surgical approaches. Materials and Methods: In this double-blind randomised controlled trial, participants were randomly allocated to one of two groups: Group 1- those who underwent medial parapatellar approach and Group 2- those who underwent mid-vastus approach. Both groups received three-phase structured rehabilitation protocol for 12 weeks. The outcome measures of SF-36, knee mobility, isometric knee musculature strength and six-minute walk distance were measured at baseline, on discharge and at review after three months. Results: The quality of life and joint specific outcome scores were better in mid-vastus approach than the popular medial parapatellar approach. The outcomes of knee flexion mobility (p=0.04), knee extension mobility (p=0.03), isometric muscle strength of quadriceps (p=0.001), isometric muscle strength of hamstrings (p=0.03), six-minute walk distance (p=0.001) and Physical Cumulative Scores (PCS) (p=0.03) were found to exhibit significant improvements at three months follow up. Conclusion: The mid-vastus approach was found to exhibit better improvements following structured rehabilitation care, in physical summary scores of quality of life and joint specific outcomes than medial parapatellar approach.

8.
Saudi J Biol Sci ; 26(3): 460-463, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30899158

RESUMO

In the present investigation, the bioactive compounds from the leaf extract of Artemisia nilagirica showed potent anti-inflammatory and antimicrobial activity. The leaf extract showed a maximum protection of human red blood cells (HRBC) with 74.63% at 20 µg/mL concentration, and the minimum hemolysis was 25.37% in a hypotonic solution with diclofenac as the control. The in vitro antimicrobial activity of plant extract against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Proteus vulgaris, Yersinia enterocolitica, Bacillus subtilis, and Candida albicans was evaluated at various concentrations (50, 100, 150, and 200 µg). The maximum zone of inhibition was observed against P. aeruginosa followed by B. subtilis, S. typhi, S. aureus and E. coli. The leaf extract also showed potent activity against C. albicans.

9.
Saudi J Biol Sci ; 25(8): 1755-1761, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30591796

RESUMO

Medicinal plants have therapeutic potential and are used worldwide to treat various diseases. In this study, the corm of Caladium x hortulanum was extracted with various solvents and implied the availability of phytochemicals such as flavonoids, alkaloids, tannins, steroids, phenols, glycosides, saponins and terpenoids. The solvent extracts of the corm showed antibacterial and antifungal activity with the growth inhibition zone ranged 0-24 mm. The isolation of phytochemicals was carried out using gel column chromatography, Thin Layer Chromatography followed by High Performance Liquid Chromatography. Gas Chromatography and Mass Spectrophotometry analysis was used to determine the phytochemicals. The corm extract showed potent antidiabetic activity on Hep G2 cell lines and CCl4 induced toxicity was elucidated. This possessed antiinflammatory property on murine monocyclic macrophage cell line RAW 264.7 showed 45.85 ±â€¯1.8% inhibition of cyclooxygenase activity. The corm extract showed hepatoprotective activity. The CCl4 incorporated Hep G2 cells showed 19.629 ±â€¯1.5% viability, whereas viability increased as 78.82 ±â€¯1.9% at 100 µg/ml of extract.

10.
J Clin Diagn Res ; 11(6): YC05-YC09, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28764280

RESUMO

INTRODUCTION: Total knee replacement (TKR) surgery has become the most successful surgery for patients with severe debilitating arthritis. The guidelines for rehabilitation progression should be tailored respecting the tissue healing parameters. Hence, the current literature states a need for protocol to mitigate these impairments and ultimately result in improved functional outcomes. OBJECTIVE: The present study aimed to validate the content of TKR rehabilitation protocol in Indian population. MATERIALS AND METHODS: The process of content validation involves development stage and expert judgment stage. The protocol was designed into three stages with extensive review of literature. After designing the protocol, nine experts in field of musculoskeletal Physiotherapy performed the judgemental process. The process of validation includes rating of experts in a 5 point likert grading on two parameters namely relevance and ease of performance. Based on expert's inputs on TKR protocol, the level of agreement, content validation index and kappa value was calculated. RESULTS: The three staged TKR protocol almost exhibited an excellent agreement on all stages. However, muscle activation exercises (except Vastus medialis obliques activation), stretching, strengthening program and functional training showed 100% agreement than other stages. CONCLUSION: The structured TKR protocol exhibited excellent content validity to its use in Indian population.

11.
J Orthop Case Rep ; 6(4): 77-79, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28164059

RESUMO

INTRODUCTION: Neurological complications due to spinal anesthesia are dysesthesia, paresthesia, cauda equina syndrome, and neuropathic joint. However, neurological complications are rare. We report a case of neuropathic joint of knee as a complication of syrinx following postspinal anesthesia. CASE REPORT: A 33-year-old female came with complaints of pain and instability of her left knee and left foot drop. She had developed weakness of her left lower limb following her cesarean section surgery done under spinal anesthesia. Clinically and radiologically, she had features of the neuropathic left knee joint which had occurred as a complication of syrinx following spinal anesthesia. CONCLUSION: The case is reported for its rarity and to highlight the possible neurological complications of spinal anesthesia.

12.
Waste Manag ; 48: 513-520, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26459187

RESUMO

The production of carboxymethyl cellulase (CMCase) by Bacillus halodurans IND18 under solid substrate fermentation (SSF) using cow dung was optimized through two level full factorial design and second order response surface methodology (RSM). The central composite design (CCD) was employed to optimize the vital fermentation parameters, such as pH of the substrate, concentration of nitrogen source (peptone) and ion (sodium dihydrogen phosphate) sources in medium for achieving higher enzyme production. The optimum medium composition was found to be 1.46% (w/w) peptone, 0.095% (w/w) sodium dihydrogen phosphate and pH 8.0. The model prediction of 4210IU/g enzyme activity at optimum conditions was verified experimentally as 4140IU/g. The enzyme was active over a broad temperature range (40-60±1°C) and pH (7.0-9.0) with maximal activity at 60±1°C and pH 8.0. This study demonstrated the potential of cow dung as novel substrate for CMCase production.


Assuntos
Bacillus/enzimologia , Celulase/química , Esterco , Agricultura/métodos , Animais , Bacillus cereus/enzimologia , Bovinos , Poluentes Ambientais/química , Fermentação , Resíduos de Alimentos , Concentração de Íons de Hidrogênio , Microbiologia Industrial/métodos , Modelos Estatísticos , Nitrogênio/química , Oryza , Peptonas/química , Pseudoalteromonas/enzimologia , Eliminação de Resíduos/métodos , Shewanella/enzimologia , Temperatura , Xanthomonas/enzimologia
13.
Biotechnol Rep (Amst) ; 7: 135-142, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28626723

RESUMO

Agro-residues were used as the substrate for the production of fibrinolytic enzyme in solid state fermentation. In this study, two-level full factorial design (25) and response surface methodology were applied to optimize a fermentation medium for the production of fibrinolytic enzyme from the marine isolate Shewanella sp. IND20. The 25 factorial design demonstrated that the physical factors (pH and moisture) and nutrient factors (trehalose, casein, and sodium dihydrogen phosphate) had significant effect on fibrinolytic enzyme production. Central composite design was employed to search for the optimal concentration of the three factors, namely moisture, pH, and trehalose, and the experimental results were fitted with a second-order polynomial model at 99% level (p < 0.0001). The optimized medium showed 2751 U/mL of fibrinolytic activity, which was 2.5-fold higher than unoptimized medium. The molecular weight of fibrinolytic enzyme was found to be 55.5 kDa. The optimum pH and temperature were 8.0 and 50 °C, respectively.

14.
J Orthop Case Rep ; 5(4): 10-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27299087

RESUMO

INTRODUCTION: Myositis ossificans progressiva is very rare with a worldwide prevalence of approximately 1 case in 2 million individuals. No ethnic, racial, or geographic predisposition has been described. Although familial forms inherited on a dominant autosomal basis have been described, most cases are sporadic. CASE REPORT: 16 yr female came to opd with complaints of progressive restriction of movements of bilateral elbow, bilateral shoulder, bilateral knee and bilateral hip for past 4 years. On examination patient is found to have short great toes of bilateral foot and ffd of all the joints. Patient is bed ridden and had acute pain for past 2 wks. Patient was evaluated and diagnosed to have myositis ossificans progressiva. Patient was treated with short course of steroids and bisphosphonates. Patient's pain improved and the patient was discharged on request as she was not willing for further management. CONCLUSION: Myositis ossificans progressiva is a rare disease with limited treatment options. At present there is no available treatment to completely cure the disease. Short course of steroids and bisphosphonates helps to relieve symptoms of acute pain.

15.
Pharm Biol ; 53(2): 174-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25289526

RESUMO

CONTEXT: Delonix elata (L.) Gamble (Fabaceae) has been used in the Indian traditional medicine system to treat rheumatism and inflammation. AIM: To assess the anti-inflammatory effect of Delonix elata flowers and to isolate the active principle. MATERIALS AND METHODS: The prompt anti-inflammatory constituent was isolated from Delonix elata flower extracts using bioassay guided fractionation in liposaccharide (LPS) stimulated RAW 264.7 macrophage cell line. The anti-inflammatory activity of extracts/fractions/sub-fractions/compounds (10, 25, and 50 µg/ml) was evaluated by estimating the levels of nitric oxide (NO), TNF-α, and IL-1ß after 24 h of LPS induction (1 µg/ml). The isolated active compound was subjected to NMR, IR, and UV analyses for structure determination. RESULTS: In an attempt to search for anti-inflammatory constituents, the active pure principle was isolated and crystallized as a white compound from Delonix elata flowers methanol extract. This active compound (50 µg/ml) decreased the release of inflammatory mediators levels such as NO (0.263 ± 0.03 µM), TNFα (160.20 ± 17.57 pg/ml), and IL-1ß (285.79 ± 15.16 pg/ml) significantly (p < 0.05); when compared to the levels of NO (0.774 ± 0.08 µM), TNFα (501.71 ± 25.14 pg/ml), and IL-1ß (712.68 ± 52.25 pg/ml) from LPS-stimulated macrophage cells. The active compound was confirmed as hesperidin with NMR, IR, and UV spectroscopy data. This is the first report of this compound from Delonix elata flowers. CONCLUSION: The findings of the study support the traditional use of Delonix elata flowers to treat inflammation.


Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Fabaceae/química , Hesperidina/isolamento & purificação , Macrófagos/efeitos dos fármacos , Extratos Vegetais/química , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/toxicidade , Bioensaio , Linhagem Celular , Fracionamento Químico , Relação Dose-Resposta a Droga , Flores/química , Hesperidina/farmacologia , Hesperidina/toxicidade , Interleucina-1beta/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
16.
Circulation ; 96(9 Suppl): II-346-51, 1997 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-9386122

RESUMO

BACKGROUND: Pulmonary hypertension causes major morbidity and mortality after congenital heart surgery, but its mechanism remains unclear. METHODS AND RESULTS: Plasma endothelin-1 (ET-1), nitric oxide (NO), and cyclic GMP (cGMP) were assayed at 6 intervals in 50 children undergoing cardiopulmonary bypass (CPB): before CPB, 10 minutes into CPB, and 0, 3, 6, and 12 hours after CPB. Three groups based on pulmonary flow and pressure were analyzed: low flow (LF, n=21), high flow/low pressure (systolic pulmonary pressure/systemic pressure ratio, Pp/Ps<50%, HF-LP, n=11), and high flow/high pressure (Pp/Ps> or =50%, HF-HP, n=19). HF-HP and HF-LP received alpha-blockers (chlorpromazine and/or prazosin). HF-HP patients received nitric oxide donors (nitroglycerin/sodium nitroprusside). ET-1 peaked at 6 hours, with its highest level in the HF-HP group (P<.01, by ANOVA). ET-1 correlated significantly with Pp/Ps at 6 hours (r2=.43, P<.005). In the HF-HP group, ET-1 remained above the other groups at 12 hours (12.7+/-2.5 pg/mL versus 6.4+/-1.1 pg/mL versus 6.5+/-3.8 pg/mL P<.05 by ANOVA). NO metabolites were elevated equivalently for the HF-HP and HF-LP groups (5.7+/-2.6 micromol/L versus 0.3.5+/-2.5 micromol/L at 12 hours, P=NS) despite nitric oxide donors and the excess ET-1 in HF-HP patients. Levels of cGMP were similarly elevated in HF-HP and HF-LP patients during this study. CONCLUSIONS: Endogenous NO may decrease vascular tone and maintain low pulmonary pressure in HF-LP patients. High levels of ET-1, inadequate NO production, and/or impaired responses to NO may increase pulmonary pressure in HF-HP patients.


Assuntos
GMP Cíclico/sangue , Endotelina-1/sangue , Cardiopatias Congênitas/cirurgia , Hipertensão Pulmonar/etiologia , Óxido Nítrico/sangue , Complicações Pós-Operatórias/etiologia , Pressão Sanguínea , Ponte Cardiopulmonar , Pré-Escolar , Feminino , Cardiopatias Congênitas/sangue , Humanos , Lactente , Masculino
17.
Exp Mol Pathol ; 64(2): 63-77, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9316585

RESUMO

Down regulation of aryl sulfotransferase IV (AST IV) in promotion/progression of liver carcinogenesis by N-2-fluorenylacetamide (2-FAA) has been established. This study examined whether the C-9 oxidized metabolites of 2-FAA, which have recently been shown to promote diethylnitrosamine (DEN)-initiated liver carcinogenesis in male Sprague-Dawley rats, effect the above change. Hence, in DEN-initiated rats, the effects of promoting regimens of 9-OH-2-FAA or 9-oxo-2-FAA, 15 oral doses at 50 and 100 mumol/kg of body weight, were compared to those of 2-FAA at 50 mumol/kg of body weight and of the vehicle on the activity of N-hydroxy(OH)-2-FAA sulfotransferase (ST), an isozyme of AST IV and AST IV expression and distribution. Relative to the vehicle, treatment with the fluorenyl compounds led to decreased levels in hepatic N-OH-2-FAA ST activity and development of hepatic nodules and tumors which had still lower levels of the ST activity than the respective remnant livers. At approximately 8 months after treatment with the C-9-oxidized compounds at doses twice that of 2-FAA, the extents of decreases in the hepatic N-OH-2-FAA ST activity and cytosolic AST IV protein in tumors were comparable to those with 2-FAA. Immunocytochemical analysis showed close association of AST IV deficiency with neoplastic liver lesions. In comparison to N-OH-2-FAA, 9-OH-2-FAA had only low and 9-oxo-2-FAA lacked sulfate acceptor activity in the presence of male rat liver cytosol or AST IV. At 3.3-fold greater concentration than N-OH-2-FAA, 9-oxo-2-FAA inhibited (27%) the sulfate acceptor activity of N-OH-2-FAA in the presence of AST IV, which suggested interference by 9-oxo-2-FAA at the active site. Although the C-9-oxidized compounds do not appear to be substrates for N-OH-2-FAA ST, their ability to cause a decrease in N-OH-2-FAA ST activity and protein similar to that of 2-FAA supports their role in hepatocarcinogenesis. Whereas 9-OH-2-FAA had a 3.9-fold greater sulfate acceptor activity in the presence of female than male rat liver cytosol and inhibited dehydroepiandrosterone ST activity of female rat liver, N-OH-2-FAA and 9-oxo-2-FAA inhibited estrone ST activity of male rat liver, suggesting that the C-9-oxidized compounds as well as N-OH-2-FAA are substrates for STs other than AST IV.


Assuntos
2-Acetilaminofluoreno/toxicidade , Arilsulfotransferase/deficiência , Carcinógenos/toxicidade , Dietilnitrosamina/toxicidade , Isoenzimas/deficiência , Neoplasias Hepáticas/enzimologia , 2-Acetilaminofluoreno/análogos & derivados , 2-Acetilaminofluoreno/metabolismo , Animais , Arilsulfotransferase/metabolismo , Carcinógenos/metabolismo , Regulação para Baixo , Sinergismo Farmacológico , Feminino , Isoenzimas/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Sulfatos/metabolismo
18.
Int J Oncol ; 7(2): 287-94, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21552838

RESUMO

The promoting potential of the C-9 oxidized metabolites of N-2-fluorenylacetamide (2-FAA) was examined and compared to that of the promoter 2-FAA in the two-stage hepatocarcinogensis system Male Sprague Dawley rats were initiated with a single intraperitoneal injection of diethylnitrosamine at 200 mg/kg of body weight (b.wt.). One, 2 and 5 weeks thereafter rats were given by gavage 5 doses per week of 2-FAA (0.05 mmol/kg of b.wt.), 9-hydroxy- or 9-oxo-2-FAA (0.05 and 0.1 mmol/kg of b.wt.) or the vehicle polyethylene glycol 400 (2 ml/kg of b.wt.). All rats underwent partial (70%) hepatectomy on day 3 after 5 initial doses. Following treatment with 2FAA, 9-hydroxy-or 9-oxo-2-FAA, the levels of gamma-glutamyl-transpeptidase activity and placental glutathione S-transferase (GST-P) were increased in the livers proportional to the increased numbers of foci of GST-P positive hepatocytes. The activities of the C-9 oxidized compounds were dose-dependent since treatment at 0.1 mmol/kg of b.wt. resulted in -2-fold greater effects than that at 0.05 mmol/kg of b.wt. The incidences of hepatocellular carcinoma increased with time after treatment and the relative order of potency was: 2-FAA>9-oxo-2-FAA>9-hydroxy-2-FAA. These data combined with our earlier evidence for preferential oxidations of 2-FAA at C-9 by hepatic microsomes of male Sprague Dawley rats support the significance of these metabolites as a promoting stimuli in liver carcinogenesis by 2-FAA.

19.
Environ Health Perspect ; 102 Suppl 6: 105-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7889829

RESUMO

The feasibility of using biochemical assays of gamma-glutamyltranspeptidase (gamma-GTP) and N-hydroxy-N-2-fluorenylacetamide sulfotransferase (N-OH-2-FAA ST) activities to monitor the effects of treatment of male Sprague-Dawley rats with a two-stage hepatocarcinogenic regimen was investigated. One week after initiation with diethylnitrosamine (200 mg/kg of bw), the rats were treated with 10 oral doses within 2 weeks of N-2-fluorenylacetamide (2-FAA) at 0.05 mmole/kg or vehicle (corn oil) at 5 ml/kg of body weight. After five doses of 2-FAA or corn oil, half of the rats in each group underwent partial (70%) hepatectomy (PH). Three days after completion of 2-FAA treatment, gamma-GTP activity increased approximately 8-fold in the livers of both the nonhepatectomized (-PH) and hepatectomized (+PH) groups. After 17 days, the enzyme activity decreased to the control level in the -PH group but increased 3.1-fold above the control level in the +PH group. After 31, 66, and 87 days, gamma-GTP activity increased only 1.4- to 2.6-fold in the -PH group, whereas that of +PH group increased 15- to 32-fold. N-OH-2-FAA ST activity, determined 3 days after completion of 2-FAA treatment, decreased by approximately 60% in the -PH and +PH groups. After 17 days, the effect of PH became evident in that the losses of N-OH-2-FAA ST activity were smaller (20%) in the -PH than in the +PH group (45.5%). After 31, 66, and 87 days, the respective decreases of 27, 29, and 41% in the +PH group were significant.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hidroxiacetilaminofluoreno/metabolismo , Neoplasias Hepáticas Experimentais/enzimologia , Fígado/enzimologia , gama-Glutamiltransferase/metabolismo , Animais , Hepatectomia , Fígado/cirurgia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/cirurgia , Masculino , Ratos , Ratos Sprague-Dawley
20.
Clin Physiol Biochem ; 9(4): 138-44, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1302169

RESUMO

Bovine aortic endothelial cells in monolayers were used to study iron and transferrin binding and transport mechanisms. Diferric bovine transferrin labeled with 59Fe was used as an iron donor. We have shown the presence of saturable iron uptake when cells were incubated with varying concentrations of diferric transferrin. This uptake decreased when the cells were treated with trypsin, ammonium chloride and methylamine. The effects of the latter two could be reversed by the addition of 2.0 mM Ca2+. Energy dependence was shown by using various electron transport/oxidative phosphorylation inhibitors. The presence of transferrin receptors on the cell surface was confirmed by their isolation, SDS-PAGE and autoradiography. There were approximately 1.5 x 10(6) transferrin receptors per cell with a Kd of 9.1 x 10(-7) M in the physiological iron range. Iron was also taken up when the cells were incubated with radioactive ferrous iron without transferrin. Uptake was not affected by receptor-mediated endocytosis inhibitors. Calcium increased ferrous iron uptake and overcame the effects of metabolic inhibitors on iron uptake from transferrin. A ferrireductase was detected in cell membranes. It is proposed that iron is transported by bovine endothelial cells by two mechanisms: one is receptor-mediated endocytosis from transferrin, and the other involves a non-endocytic mechanism from transferrin and Fe2+, which is possibly promoted by Ca2+.


Assuntos
Endotélio Vascular/metabolismo , FMN Redutase , Ferro/metabolismo , Receptores da Transferrina/metabolismo , Transferrina/metabolismo , Animais , Aorta/metabolismo , Sítios de Ligação , Transporte Biológico , Cálcio/farmacologia , Bovinos , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Endotélio Vascular/citologia , Compostos Férricos/metabolismo , Compostos Ferrosos/metabolismo , NADH NADPH Oxirredutases/metabolismo
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