Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
BMC Med Educ ; 23(1): 843, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936105

RESUMO

INTRODUCTION: Medical Education studies suggest that medical students experience depression, anxiety and psychopathological symptomatology in a proportion higher than in the rest of the population. In the present study, we aimed to conduct a nationwide analysis to describe student's perceptions of Educational Climate in Spanish medical schools, and its relationship with psychopathological symptomatology. METHODS: The study was carried out in 2022 in all 44 medical schools in Spain, and analyses the academic climate, and psychopathological symptomatology among medical students (n = 4374). To measure these variables, we used the Dundee Ready Education Environment Measure (DREEM) for academic climate, and the SA-45 (Symptom Assessment-45 Questionnaire was used to assess psychopathological symptomatology. RESULTS: The mean DREEM global score was low, 95.8 (SD 22.6). Worse perception of the academic climate has been found in females (t -2.21, p 0.027), in students of the clinical academic years (t 16.9, p < 0.001), and public medical schools ( t 15.6, p < 0.001). The SA45 general index score was high (p90) in 25.6% of participants. In respect of gender, female students presented higher levels of SA45 general index score, depression, interpersonal sensitivity, somatization, anxiety, obsession-compulsion, and phobic anxiety symptoms. Higher DREEM global and subscale scores corresponded to a higher SA-45 global index score and higher SA-45 subscale scores. CONCLUSIONS: Our study suggests a correlation between a poor perception of academic climate, increased depression, anxiety, and other psychopathological symptoms, with a pattern that varies between different faculties. The perception of academic climate varied between medical schools, as did the psychopathological symptoms scores. Our finding suggests the prevalence of these variables in medical students is, at least in part, attributable to factors directly related to the learning atmosphere.


Assuntos
Educação de Graduação em Medicina , Transtornos Mentais , Estudantes de Medicina , Humanos , Feminino , Aprendizagem , Inquéritos e Questionários , Percepção Social
2.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446122

RESUMO

INTRODUCTION: Previously, we found that intracellular calcium (Ca2+) homeostasis is altered in platelets from an experimental model of liver cirrhosis, namely the bile-duct-ligated (BDL) rat. These alterations are compatible with the existence of a hypercoagulable state. OBJECTIVE: In the present study, we analyzed the role of nitric oxide in the abnormal calcium signaling responses of an experimental cirrhosis model, the bile duct-ligated rat. METHODS: Chronic treatment with L-NAME was used to inhibit NO production in a group of control and BDL animals, and the responses compared to those obtained in a control and BDL untreated group (n = 6 each). The experiments were conducted on isolated platelets loaded with fura-2, using fluorescence spectrometry. RESULTS: Chronic treatment with L-NAME increased thrombin-induced Ca2+ release from internal stores in both control and BDL rats. However, the effect was significantly greater in the BDL rats (p < 0.05). Thrombin-induced calcium entry from the extracellular space was also elevated but at lower doses and, similarly in both control and BDL platelets, treated with the NO synthesis inhibitor. Capacitative calcium entry was also enhanced in the control platelets but not in platelets from BDL rats treated with L-NAME. Total calcium in intracellular stores was elevated in untreated platelets from BDL rats, and L-NAME pretreatment significantly (p < 0.05) elevated these values both in controls and in BDL but significantly more in the BDL rats (p < 0.05). CONCLUSIONS: Our results suggest that nitric oxide plays a role in the abnormal calcium signaling responses observed in platelets from BDL rats by interfering with the mechanism that releases calcium from the internal stores.


Assuntos
Cirrose Hepática Biliar , Ratos , Animais , Óxido Nítrico/uso terapêutico , Plaquetas , Cálcio , Ratos Sprague-Dawley , NG-Nitroarginina Metil Éster/farmacologia , Trombina/farmacologia , Trombina/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Ligadura
3.
BMC Med Educ ; 22(1): 752, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36320062

RESUMO

BACKGROUND: The aim of this study was to find out specialty training preferences of senior medical students from three medical schools in Turkey, Spain, and Pakistan. METHODS: A Discrete Choice Experiment was carried out using an electronic form for students in three countries in 2021-2022 term. Each choice set in the form consisted of two hypothetical specialty training positions. The attributes were location, earnings, working conditions, personal perspective, quality of education, probability of malpractice, and prestige. Conditional logit model was used to estimate participants' preferences and "willingness to accept" values. RESULTS: The most valued attribute was "personal perspective on specialty area" for Turkish and Spanish students, while this attribute was not meaningful for Pakistani students. Turkish students needed a 204% of change in their income for a swap between the specialty that they like and not like. This tradeoff necessitated a 300% change for Spanish students. The most valued attribute for Pakistani students, which was "working conditions", necessitated a 97% increase in income to switch from working in good conditions to working in poor conditions. CONCLUSION: In this first multinational DCE study in the medical education literature, we found the preferences of medical students in Turkey, Spain, and Pakistan are affected to various extents by several factors.


Assuntos
Estudantes de Medicina , Humanos , Escolha da Profissão , Paquistão , Comportamento de Escolha , Turquia , Inquéritos e Questionários
4.
Biomedicines ; 10(6)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35740253

RESUMO

This study investigated the vasoactive effects of des-aspartate-angiotensin-I (DAA-I) in male Wistar rats on whole body vascular bed, isolated perfused kidneys, and aortic rings. Dose-response curves to DAA-I were compared with those to angiotensin II (Ang II). The Ang II-type-1 (AT1) receptor blocker, losartan, was used to evaluate the role of AT1 receptors in the responses to DAA-I. Studies were also conducted of the responsiveness in aortic rings after endothelium removal, nitric oxide synthase inhibition, or AT2 receptor blockade. DAA-I induced a dose-related systemic pressor response that was shifted to the right compared with Ang II. Losartan markedly attenuated the responsiveness to DAA-I. DAA-I showed a similar pattern in renal vasculature and aortic rings. In aortic rings, removal of endothelium and nitric oxide inhibition increased the sensitivity and maximal response to DAA-I and Ang II. AT2 receptor blockade did not significantly affect the responsiveness to DAA-I. According to these findings, DAA-I increases the systemic blood pressure and vascular tone in conductance and resistance vessels via AT1 receptor activation. This vasoconstrictor effect of DAA-I participates in the homeostatic control of arterial pressure, which can also contribute to the pathogenesis of hypertension. DAA-I may therefore be a potential therapeutic target in cardiovascular disease.

5.
Curr Top Med Chem ; 22(9): 735-745, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34749613

RESUMO

Flavonoids are a class of substances of a vegetal origin with many interesting actions from the point of view of human disease. Interest in flavonoids in the diet has increased in recent years due to the publication of basic, clinical and epidemiological studies that have shown a whole array of salutary effects related to intake of flavonols and flavones as well as a lower morbility and mortality of cardiovascular diseases. Since arterial hypertension is the most common modifiable risk factor for cardiovascular diseases, this review will focus mainly on the effects of flavonoids on the cardiovascular system with relation to the elevation of blood pressure. Its antihypertensive effects as well as the many investigations performed in experimental models of arterial hypertension, are reviewed in this mini-review.


Assuntos
Doenças Cardiovasculares , Hipertensão , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico , Modelos Teóricos
6.
PLoS One ; 16(12): e0260359, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34855803

RESUMO

Medical Education studies suggest that medical students experience mental distress in a proportion higher than in the rest of the population In the present study, we aimed to conduct a nationwide analysis of the prevalence of mental health problems among medical students. The study was carried out in 2020 in all 43 medical schools in Spain, and analyzes the prevalence of depression, anxiety, empathy and burnout among medical students (n = 5216). To measure these variables we used the Beck Depression Inventory Test for assessing depression, the Maslach Burnout Inventory Survey for Students was used for burnout, the State-Trait Anxiety Inventory (STAI) was used to assess anxiety state and trait and the Jefferson Empathy Scale 12 to obtain empathy scores. In relation to depression, the data indicate an overall prevalence of 41%, with 23.4% of participants having moderate to severe levels, and 10% experiencing suicidal ideation. Burnout prevalence was 37%, significantly higher among 6th year than among 1st year students. Anxiety levels were consistent with those reported previously among medical students (25%), and were higher than in the general population for both trait and state anxiety. The prevalence of trait anxiety was higher among women. Empathy scores were at the top end of the scale, with the highest-scoring group (>130) containing a greater percentage of women. Similarly to those published previously for other countries, these results provide a clear picture of the mental disorders affecting Spanish medical students. Medicine is an extremely demanding degree and it is important that universities and medical schools view this study as an opportunity to ensure conditions that help minimize mental health problems among their students. Some of the factors underlying these problems can be prevented by, among other things, creating an environment in which mental health is openly discussed and guidance is provided. Other factors need to be treated medically, and medical schools and universities should therefore provide support to students in need through the medical services available within their institutions.


Assuntos
Estudantes de Medicina , Adulto , Depressão , Empatia , Feminino , Humanos , Masculino
7.
Healthcare (Basel) ; 9(11)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34828626

RESUMO

BACKGROUND: Medical professionalism, defined as commitment to the primacy of patient welfare, is the basis for doctor-patient-society relationships, but previous research with medical students has shown that professionalism and social commitment to medicine may be waning. To determine if this trend also appears in recently qualified practicing doctors, we surveyed 90 newly graduated doctors currently working as medical residents in two university hospitals in Murcia, Spain. A previously validated questionnaire that studies the perception of six categories (responsibility, altruism, service, excellence, honesty and integrity, and respect) defining medical professionalism was used. RESULTS: A good perception of professionalism was found among medical residents, with more than 70% positive responses in all these six categories. There is an increasing trend in the number of negative responses as the residency goes on. Altruism was the category with the greatest percentage of negative answers (22.3%) and Respect was the category with the lowest percentage (12.9%). CONCLUSIONS: The results show a good professionalism perception in medical residents, but also a slight decline in positive answers that began during medical school. A significant trend was found when including both students and residents. Although there were some differences between students and residents, these were not statistically significant. Educational interventions are needed both at the level of medical school and postgraduate medical residency.

8.
Clin Case Rep ; 9(3): 1408-1415, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33768856

RESUMO

Our results do not support any effect of FVIII on platelet function in patients with severe HA treated under the regime of prophylaxis.

9.
Int J Mol Sci ; 21(21)2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33138007

RESUMO

The National Institutes of Health (NIH) Biomarkers Definitions Group has defined a biomarker as "A characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention [...].


Assuntos
Biomarcadores/análise , Biomarcadores/metabolismo , Nefropatias/diagnóstico , Humanos , Nefropatias/metabolismo , Nefropatias/terapia , Prognóstico
10.
Int J Mol Sci ; 21(16)2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32764495

RESUMO

Aminopeptidases (APs) are metalloenzymes that hydrolyze peptides and polypeptides by scission of the N-terminus amino acid and that also participate in the intracellular final digestion of proteins. APs play an important role in protein maturation, signal transduction, and cell-cycle control, among other processes. These enzymes are especially relevant in the control of cardiovascular and renal functions. APs participate in the regulation of the systemic and local renin-angiotensin system and also modulate the activity of neuropeptides, kinins, immunomodulatory peptides, and cytokines, even contributing to cholesterol uptake and angiogenesis. This review focuses on the role of four key APs, aspartyl-, alanyl-, glutamyl-, and leucyl-cystinyl-aminopeptidases, in the control of blood pressure (BP) and renal function and on their association with different cardiovascular and renal diseases. In this context, the effects of AP inhibitors are analyzed as therapeutic tools for BP control and renal diseases. Their role as urinary biomarkers of renal injury is also explored. The enzymatic activities of urinary APs, which act as hydrolyzing peptides on the luminal surface of the renal tubule, have emerged as early predictive renal injury biomarkers in both acute and chronic renal nephropathies, including those induced by nephrotoxic agents, obesity, hypertension, or diabetes. Hence, the analysis of urinary AP appears to be a promising diagnostic and prognostic approach to renal disease in both research and clinical settings.


Assuntos
Aminopeptidases/genética , Biomarcadores/sangue , Hipertensão/genética , Insuficiência Renal Crônica/genética , Aminopeptidases/sangue , Aminopeptidases/classificação , Pressão Sanguínea/genética , Sistema Cardiovascular/metabolismo , Sistema Cardiovascular/patologia , Cistinil Aminopeptidase/sangue , Cistinil Aminopeptidase/genética , Glutamil Aminopeptidase/sangue , Glutamil Aminopeptidase/genética , Humanos , Hipertensão/sangue , Hipertensão/patologia , Rim/metabolismo , Rim/patologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/patologia , Sistema Renina-Angiotensina/genética
11.
J Otol ; 14(1): 12-16, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30936896

RESUMO

A rat model of chronic tympanic membrane perforation was developed to be used in the search of new materials for the sealing of these perforations. A longitudinal study was carried out in rats subjected to incisional myringotomy followed by the application of mitomycin C alone or with dexamethasone. Rats were checked at days 3, 7, 10, 14 and weekly thereafter until perforation closure, for up to 6 months. The addition of dexamethasone is a key component in order to obtain a chronic opening. Myringotomies treated with saline had a mean healing time of 8.5 days. At 8 weeks, between 62.5% and 77.7% of tympanic membranes treated with mitomycin C and dexamethasone remained perforated and at 6 months this number fell to 21.4%. This technique is able to maintain most tympanic membrane perforations patent for at least 8 weeks. This rat model is adequate for its use in preclinical or translational research.

12.
BMC Res Notes ; 11(1): 826, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30463605

RESUMO

OBJECTIVE: An e-portfolio was used to determine the optimal number of times students need to repeat a procedure before they are fully capable of performing it without supervision. The results were compared with the actual number of repetitions performed during the internship period. We also asked these students and their teachers about the optimal number of times each skill should be repeated before it could be considered fully acquired. The questionnaire was answered by 98.6% of the students and 70.3% of their teachers. RESULTS: Both students and teachers agreed on a similar optimal value for 16 out of the 21 clinical procedures selected; in the remaining 5, teachers thought that students needed to repeat the procedure more times than the number stated by students. When these optimal values were compared with the actual values recorded in the portfolio during the internships, it was found that about half of all clinical procedures were carried out fewer times than expected, thus providing important feedback about the rotation-based training process. Quantitative information collected in the portfolios revealed a moderate mismatch between students' and teachers' perceptions of training needs.


Assuntos
Competência Clínica , Currículo , Educação Médica/métodos , Estudantes de Medicina , Traumatologia/educação , Adulto , Retroalimentação , Feminino , Humanos , Internato e Residência , Masculino , Mentores , Pessoa de Meia-Idade , Espanha , Inquéritos e Questionários , Adulto Jovem
13.
Nutrients ; 10(8)2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115889

RESUMO

Many studies have shown that flavonoids are effective as antihypertensive drugs in arterial hypertension. In the present work, we have analyzed the effects of some flavonoid extracts in the spontaneous hypertensive rat model (SHR). An important feature of this study is that we have used a low dose, far from those that are usually applied in human therapy or experimental animals, a dose that responded to the criterion of a potential future commercial use in human subjects. Treatments were carried out for 6 and 12 weeks in two groups of SHR rats, which received apigenin, lemon extract, grapefruit + bitter orange (GBO) extracts, and cocoa extract. Captopril was used as a positive control in the SHR group treated for 6 weeks (SHR6) and Diosmin was used as the industry reference in the SHR group treated for 12 weeks (SHR12). Captopril and GBO extracts lowered the high arterial pressure of the SHR6 animals, but none of the extracts were effective in the SHR12 group. Apigenin, lemon extract (LE), GBO, and captopril also improved aortic vascular relaxation and increased plasma and urinary excretion of nitrites, but only in the SHR6 group. Kidney and urinary thiobarbituric acid reactive substances (TBARS) were also significantly reduced by GBO in the SHR6 rats. Apigenin also improved vascular relaxation in the SHR12 group and all the flavonoids studied reduced urinary thiobarbituric acid reactive substances (TBARS) excretion and proteinuria. Vascular abnormalities, such as lumen/wall ratio in heart arteries and thoracic aorta, were moderately improved by these treatments in the SHR6 group. In conclusion, the flavonoid-rich extracts included in this study, especially apigenin, LE and GBO improved vascular vasodilatory function of young adult SHRs but only the GBO-treated rats benefited from a reduction in blood pressure. These extracts may be used as functional food ingredients with a moderate therapeutic benefit, especially in the early phases of arterial hypertension.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Flavonoides/farmacologia , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Captopril/administração & dosagem , Captopril/farmacologia , Flavonoides/administração & dosagem , Flavonoides/química , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
14.
Front Physiol ; 9: 394, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29740333

RESUMO

This review summarizes the latest advances in knowledge on the effects of flavonoids on renal function in health and disease. Flavonoids have antihypertensive, antidiabetic, and antiinflammatory effects, among other therapeutic activities. Many of them also exert renoprotective actions that may be of interest in diseases such as glomerulonephritis, diabetic nephropathy, and chemically-induced kidney insufficiency. They affect several renal factors that promote diuresis and natriuresis, which may contribute to their well-known antihypertensive effect. Flavonoids prevent or attenuate the renal injury associated with arterial hypertension, both by decreasing blood pressure and by acting directly on the renal parenchyma. These outcomes derive from their interference with multiple signaling pathways known to produce renal injury and are independent of their blood pressure-lowering effects. Oral administration of flavonoids prevents or ameliorates adverse effects on the kidney of elevated fructose consumption, high fat diet, and types I and 2 diabetes. These compounds attenuate the hyperglycemia-disrupted renal endothelial barrier function, urinary microalbumin excretion, and glomerular hyperfiltration that results from a reduction of podocyte injury, a determinant factor for albuminuria in diabetic nephropathy. Several flavonoids have shown renal protective effects against many nephrotoxic agents that frequently cause acute kidney injury (AKI) or chronic kidney disease (CKD), such as LPS, gentamycin, alcohol, nicotine, lead or cadmium. Flavonoids also improve cisplatin- or methotrexate-induced renal damage, demonstrating important actions in chemotherapy, anticancer and renoprotective effects. A beneficial prophylactic effect of flavonoids has been also observed against AKI induced by surgical procedures such as ischemia/reperfusion (I/R) or cardiopulmonary bypass. In several murine models of CKD, impaired kidney function was significantly improved by the administration of flavonoids from different sources, alone or in combination with stem cells. In humans, cocoa flavanols were found to have vasculoprotective effects in patients on hemodialysis. Moreover, flavonoids develop antitumor activity against renal carcinoma cells with no toxic effects on normal cells, suggesting a potential therapeutic role in patients with renal carcinoma.

15.
Nutrients ; 10(4)2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29652818

RESUMO

BACKGROUND: we have evaluated the antihypertensive effect of several flavonoid extracts in a rat model of arterial hypertension caused by chronic administration (6 weeks) of the nitric oxide synthesis inhibitor, L-NAME. METHODS: Sprague Dawley rats received L-NAME alone or L-NAME plus flavonoid-rich vegetal extracts (Lemon, Grapefruit + Bitter Orange, and Cocoa) or purified flavonoids (Apigenin and Diosmin) for 6 weeks. RESULTS: L-NAME treatment resulted in a marked elevation of blood pressure, and treatment with Apigenin, Lemon Extract, and Grapefruit + Bitter Orange extracts significantly reduced the elevated blood pressure of these animals. Apigenin and some of these flavonoids also ameliorated nitric oxide-dependent and -independent aortic vasodilation and elevated nitrite urinary excretion. End-organ abnormalities such as cardiac infarcts, hyaline arteriopathy and fibrinoid necrosis in coronary arteries and aorta were improved by these treatments, reducing the end-organ vascular damage. CONCLUSIONS: the flavonoids included in this study, specially apigenin, may be used as functional food ingredients with potential therapeutic benefit in arterial hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Flavonoides/uso terapêutico , Hipertensão/induzido quimicamente , Rim/fisiologia , NG-Nitroarginina Metil Éster/toxicidade , Extratos Vegetais/uso terapêutico , Animais , Anti-Hipertensivos/química , Apigenina/administração & dosagem , Apigenina/uso terapêutico , Hipertensão/tratamento farmacológico , Masculino , Extratos Vegetais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
16.
MedEdPublish (2016) ; 7: 276, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-38089186

RESUMO

This article was migrated. The article was marked as recommended. In Spain, and probably around the world, the degree of Medicine is one of the most appreciated studies by the students. Not only the influence of job prospects, better than in other University careers, but also the study of a scientific career with many specialization areas or the joy felt by doctors when they manage to help a very sick patient, are some reasons to undertake the adventure to become a doctor. Since the demand to study Medicine is so high, it is not strange that most people with interest stay out of the process, since, at least in Spain, only the high school students with the best records are able to enter into a School of Medicine. But becoming a doctor is more than the study of a University Degree for 6 years. They need also a postgraduate specialization (MIR), in Hospitals of the National Health System, as a necessary step in order to be able to practice Medicine, either in public or private institutions. However, this road is not free from problems since there has been a decrease in the number of MIR specialization places offered without a similar reduction in the number of undergraduate positions. Moreover, the number of medical schools has not stopped growing and places Spain as one of the countries with the highest ratio of Medical Schools per inhabitant. This situation can lead to a scenario similar to that experienced in the 80s and 90s, where we witnessed an increase in the number of Specialist Physicians without Official Title (called MESTOS). As of November 2018, around 4,000 medical graduates cannot access specialized health training and may be forced into unemployment or emigration.

17.
Front Physiol ; 8: 384, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28638347

RESUMO

Previously, we have found that intracellular calcium homeostasis is altered in platelets from an experimental model of liver cirrhosis, the bile-duct ligated (BDL) rat; these alterations are compatible with the existence of a hypercoagulable state and related to an enhanced intracellular calcium release evoked by thrombin and an increased amount of calcium stored in the intracellular organelles. In the present study we have investigated the role of bile acids in those alterations of the BDL cirrhotic model. Cholic acid (CA) or deoxycholic acid (DCA) did not change P-selectin expression or platelet aggregation in any group but elevated baseline platelet calcium levels. Incubation with both bile acids reduced calcium release after stimulation with thrombin in the absence of extracellular calcium. Pretreatment with CA but not with DCA reduced significantly thrombin-induced calcium entry in all three experimental groups. The capacitative calcium entry was also significantly lower in platelets pretreated with both bile acids. The simultaneous addition of thapsigargin and ionomycin to estimate the total amount of calcium in platelet internal stores was decreased by pretreatment with both CA and DCA, although these changes were significantly different in the control rats only with CA and in the BDL platelets with DCA. These results indicate that CA and DCA reduce calcium movements in platelets of control and BDL animals, thus suggesting that bile acids do not participate in the alterations observed in the BDL cirrotic model.

18.
Platelets ; 28(7): 698-705, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28150525

RESUMO

Previously, we have found that intracellular calcium homeostasis is altered in platelets from an experimental model of liver cirrhosis, the bile-duct ligated (BDL) rat; these alterations are compatible with the existence of a hypercoagulable state. Different studies indicate that cholestatic diseases are associated with hyperhomocysteinemia; thus, we hypothetized that it could contribute to those platelet alterations. In the present study, we have investigated the role of homocysteine (HCY) in platelet aggregation and calcium signaling in the BDL model. The effect of chronic folic acid treatment was also analyzed. Acute treatment with HCY increased the aggregation response to ADP and calcium responses to thrombin in platelets of control and BDL rats. Capacitative calcium entry was not altered by HCY. Chronic treatment with folic acid decreased platelet aggregation in control and BDL rats, but this decrease was greater in BDL rats. In folic acid-treated rats, thrombin-induced calcium entry and release were decreased in platelet of control rats but unaltered in BDL rats; however, capacitative calcium entry was decreased in platelets of control and BDL rats treated with folic acid. Reactive oxygen species were produced at higher levels by BDL platelets after stimulation with HCY or thrombin and folic acid normalized these responses. HCY plays a role in the enhanced platelet aggregation response of BDL rats, probably through an enhanced formation of ROS. Folic acid pretreatment normalizes many of the platelet alterations shown by BDL rats.


Assuntos
Cálcio/metabolismo , Colestase/sangue , Ácido Fólico/farmacologia , Homocisteína/farmacologia , Cirrose Hepática Biliar/sangue , Agregação Plaquetária/efeitos dos fármacos , Difosfato de Adenosina/farmacologia , Administração Oral , Animais , Ductos Biliares/cirurgia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Plaquetas/patologia , Sinalização do Cálcio , Colestase/patologia , Modelos Animais de Doenças , Homocisteína/antagonistas & inibidores , Ligadura , Cirrose Hepática Biliar/patologia , Masculino , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Trombina/farmacologia
19.
Adv Med Educ Pract ; 7: 57-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26929675

RESUMO

This article investigates whether a reflexive portfolio is instrumental in determining the level of acquisition of clinical competences in traumatology, a subject in the 5th year of the degree of medicine. A total of 131 students used the portfolio during their clinical rotation of traumatology. The students' portfolios were blind evaluated by four professors who annotated the existence (yes/no) of 23 learning outcomes. The reliability of the portfolio was moderate, according to the kappa index (0.48), but the evaluation scores between evaluators were very similar. Considering the mean percentage, 59.8% of the students obtained all the competences established and only 13 of the 23 learning outcomes (56.5%) were fulfilled by >50% of the students. Our study suggests that the portfolio may be an important tool to quantitatively analyze the acquisition of traumatology competences of medical students, thus allowing the implementation of methods to improve its teaching.

20.
Clin Sci (Lond) ; 115(2): 57-68, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18184108

RESUMO

In liver cirrhosis, elevated levels of NO and ROS (reactive oxygen species) might greatly favour the generation of peroxynitrite. Peroxynitrite is a highly reactive oxidant and it can potentially alter the vascular reactivity and the function of different organs. In the present study, we evaluated whether peroxynitrite levels are related to the progression of renal vascular and excretory dysfunction during experimental cirrhosis induced by chronic BDL (bile-duct ligation) in rats. Experiments were performed at 7, 15 and 21 days after BDL in rats and in rats 21 days post-BDL chronically treated with L-NAME (N(G)-nitro-L-arginine methyl ester). Sodium balance, BP (blood pressure), basal RPP (renal perfusion pressure) and the renal vascular response to PHE (phenylephrine) and ACh (acetylcholine) in isolated perfused kidneys were measured. NO levels were calculated as 24-h urinary excretion of nitrites, ROS as TBARS (thiobarbituric acid-reacting substances), and peroxynitrite formation as the renal expression of nitrotyrosine. BDL rats had progressive sodium retention, and decreased BP, RPP and renal vascular responses to PHE and ACh in the time following BDL. They also had increasing levels of NO and ROS, and renal nitrotyrosine accumulation,especially in the medulla. All of these changes were either prevented or significantly decreased by chronic L-NAME administration. In conclusion, these results suggest that the increasing levels of peroxynitrite might contribute to the altered renal vascular response and sodium retention in the development of the experimental biliary cirrhosis. Moreover, the beneficial effects of decreasing NO synthesis are, at least in part, mediated by anti-peroxinitrite-related effects.


Assuntos
Cirrose Hepática Experimental/fisiopatologia , NG-Nitroarginina Metil Éster/farmacologia , Circulação Renal/efeitos dos fármacos , Tirosina/análogos & derivados , Animais , Peso Corporal , Doença Crônica , Rim/metabolismo , Rim/patologia , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Óxido Nítrico/metabolismo , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Circulação Renal/fisiologia , Baço/patologia , Tirosina/metabolismo , Tirosina/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA