Eduardo Abbott

Role of reactive oxygen species in bradykinin-induced proliferation of vascular smooth muscle cells

In addition to the induction of cell proliferation and migration, bradykinin (BK) can increase c-fos mRNA expression, activate ERK 1/2 and generate reactive oxygen species (ROS) in vascular smooth muscle cells (VSMC). It is not known, however, whether BK can induce cellular proliferation and extracellular matrix production via redox-sensitive signaling pathways. We investigated the role(s) of ROS in proliferation, migration and collagen synthesis induced by BK in VSMC derived from Sprague Dawley rat aorta. BK (10 nM) increased VSMC proliferation by 30% (n=5); this proliferation was inhibited by the antioxidants N-acetylcysteine (20 mM) and alpha-lipoic acid (LA, 250 mM). In addition, BK induced an increase in cell migration and in collagen levels that were blocked by LA. ROS production induced by BK (n=10) was significantly inhibited by bisindolylmaleimide (4microM) and by PD98059 (40microM). These results suggest that: 1) ROS participate in the mechanism(s) used by bradykinin to induce cellular proliferation; 2) bradykinin induces ROS generation through a pathway that involves the kinases PKC and MEK; and 3) ROS participate in the pathways mediating cell migration and the production of collagen as a response to treatment with bradykinin. To our knowledge, this is the first report describing mechanisms to explain the participation of ROS in the cellular proliferation and extracellular matrix pathway regulated by BK.

Personalized Video Feedback and Repeated Task Practice Improve Laparoscopic Knot-Tying Skills: Two Controlled Trials

Purpose Compare the effect of personalized feedback (PF) vs. task demonstration (TD), both delivered via video, on laparoscopic knot-tying skills and perceived workload; and evaluate the effect of repeated practice. Method General surgery interns and research fellows completed four repetitions of a simulated laparoscopic knot-tying task at one-month intervals. Midway between repetitions, participants received via e-mail either a TD video (demonstration by an expert) or a PF video (video of their own performance with voiceover from a blinded senior surgeon). Each participant received at least one video per format, with sequence randomly assigned. Outcomes included performance scores and NASA Task Load Index (NASA-TLX) scores. To evaluate the effectiveness of repeated practice, scores from these trainees on a separate delayed retention test were compared against historical controls who did not have scheduled repetitions. Results Twenty-one trainees completed the randomized study. Mean change in performance scores was significantly greater for those receiving PF (difference = 23.1 of 150 [95% confidence interval (CI): 0, 46.2], P = .05). Perceived workload was also significantly reduced (difference = −3.0 of 20 [95% CI: −5.8, −0.3], P = .04). Compared with historical controls (N = 93), the 21 with scheduled repeated practice had higher scores on the laparoscopic knot-tying assessment two weeks after the final repetition (difference = 1.5 of 10 [95% CI: 0.2, 2.8], P = .02). Conclusions Personalized video feedback improves trainees’ procedural performance and perceived workload compared with a task demonstration video. Brief monthly practice sessions support skill acquisition and retention.

DISFUNCIONALIDAD ANTIOXIDANTE DE LAS LIPOPROTEÍNAS DE ALTA DENSIDAD (HDL) EN PACIENTES DIABÉTICOS DESCOMPENSADOS

INTRODUCTION high density lipoproteins (HDL) have important cardiovascular protective effects mediated by their role in reverse cholesterol transport as well as other functional activities, including significant anti-inflammatory and antioxidant properties. It has been shown that HDL anti-inflammatory and antioxidant functions are defective in metabolically stable diabetic patients; however they have not been evaluated during a hyperglycemic crisis. AIM to determine the antioxidant activity of HDL during a severe diabetic decompensation and to analyze whether this function is restored after resolution of the acute event. METHODS the antioxidant activity of HDL was measured in vitro by a fluorescent assay in plasma samples obtained from diabetic patients with acute metabolic decompensation at admission, recovery within the hospital and follow-up in ambulatory care. As a comparison, HDL particles from some healthy subjects were used as controls. RESULTS the HDL antioxidant function was significantly reduced in patients during an acute diabetic decompensation compared with the control group, and was gradually restored reaching normal values during the ambulatory follow-up. Hyperglycemic crisis also showed low plasma paraoxonase-1 activity, which increased significantly during at follow-up. CONCLUSION HDL particles isolated from acute diabetic descompensated patients exhibit a significantly and reversibly low antioxidant capacity, which is probably due to a reduced paraoxonase-1 activity.

Profilaxis de enfermedad tromboembólica en pacientes hospitalizados con patología médica, estrechando la brecha entre las guías y la práctica clínica

Thromboembolic disease is the main preventable cause of in-hospital death. Approximately 10% of nosocomial deaths are attributable to pulmonary embolism and in most cases, the diagnosis is not suspected before the autopsy. There are cost effective measures to decrease the incidence of thromboembolic disease. Pharmacological prophylaxis decreases the incidence of deep venous thrombosis by 65% and the incidence of pulmonary embolism by 35 to 55%. Despite this data and the presence of clinical guidelines, prophylaxis of thromboembolic disease is used only in 40% of medical patients and in 65% of surgical patients with recommended indications. We review the evidence that supports the use of thromboprophylaxis and the different strategies that may increase the compliance of physicians with its use. A protocol implemented in our institution is also proposed.

Trends in P Value, Confidence Interval, and Power Analysis Reporting in Health Professions Education Research Reports: A Systematic Appraisal

Purpose To characterize reporting of P values, confidence intervals (CIs), and statistical power in health professions education research (HPER) through manual and computerized analysis of published research reports. Method The authors searched PubMed, Embase, and CINAHL in May 2016, for comparative research studies. For manual analysis of abstracts and main texts, they randomly sampled 250 HPER reports published in 1985, 1995, 2005, and 2015, and 100 biomedical research reports published in 1985 and 2015. Automated computerized analysis of abstracts included all HPER reports published 1970–2015. Results In the 2015 HPER sample, P values were reported in 69/100 abstracts and 94 main texts. CIs were reported in 6 abstracts and 22 main texts. Most P values (≥77%) were ⩽.05. Across all years, 60/164 two-group HPER studies had ≥80% power to detect a between-group difference of 0.5 standard deviations. From 1985 to 2015, the proportion of HPER abstracts reporting a CI did not change significantly (odds ratio [OR] 2.87; 95% CI 1.04, 7.88) whereas that of main texts reporting a CI increased (OR 1.96; 95% CI 1.39, 2.78). Comparison with biomedical studies revealed similar reporting of P values, but more frequent use of CIs in biomedicine. Automated analysis of 56,440 HPER abstracts found 14,867 (26.3%) reporting a P value, 3,024 (5.4%) reporting a CI, and increased reporting of P values and CIs from 1970 to 2015. Conclusions P values are ubiquitous in HPER, CIs are rarely reported, and most studies are underpowered. Most reported P values would be considered statistically significant.

Entrega de turno: un desafío para docentes y residentes

Introduccion La entrega de turno es una instancia ubicua y repetitiva durante la estadia hospitalaria de un paciente, que no solo involucra al personal medico a cargo y que incluso esta presente en el momento de alta, cuando se traspasa el cuidado del enfermo al equipo de atencion ambulatoria. Esta ampliamente demostrado en la literatura que es un espacio vulnerable y susceptible de errores, que inciden directamente en los outcomes. Existen diversas recomendaciones con respecto a la forma y el contenido de una entrega de turno efectiva; sin embargo, existe poca informacion acerca del cumplimiento de dichas recomendaciones. Metodologia El ano 2013, se realizo encuesta a los residentes que ingresaban al programa de Medicina Interna de la Universidad Catolica acerca de su conocimiento y experiencia con entrega de turno efectiva; seguidamente, se hizo una capacitacion acerca de la importancia y las recomendaciones para una entrega de turno efectiva y se estandarizo la entrega de turno en un formato electronico. Desde los 6 meses de residencia en adelante, se hizo una observacion anonima de la entrega de turno, aplicando un cuestionario con las principales recomendaciones y se evaluo el cumplimiento de las mismas. Resultados Se realizaron 40 observaciones anonimas, observando que el 100% de los residentes ocupaban el formato estandarizado; sin embargo, al analizar la forma y el contenido de la entrega, solo existia un 60% de cumplimiento, siendo los puntos mas criticos el contar con un espacio y tiempo protegido y el no dejar un plan claro en el traspaso de cuidados. Conclusiones De acuerdo con los resultados, podemos concluir que existe una clara conciencia de la importancia de la entrega de turno, por lo que los residentes adhirieron con facilidad al formato estandarizado. Sin embargo, aun se debe trabajar arduamente para que exista una instancia formal de entrega de turno y se debe capacitar continuamente a residentes y staff acerca de los contenidos de una entrega de turno efectiva.

HIPOGLICEMIA RECURRENTE COMO CAUSA REVERSIBLE DE SÍNDROME DEMENCIAL EN ADULTOS MAYORES DIABÉTICOS, A PROPÓSITO DE UN CASO.

We report a 78 year-old diabetic woman, treated with gliburide and metformin, consulting in the emergency room for a non fuctuating impairment in consciousness. She had a history of similar episodes in the last two months. A brain CAT scan showed an old putamen lacunar infarction. Noteworthy was the presence of a low glycosilated hemoglobin level of 5.2%. Hypoglycemic medications were discontinued and the patient was discharged in good conditions. After six months of follow up, the patient did not have further episodes of impairment of consciousness.