Problem-based learning implementation in an intensive course of anaesthesiology: a preliminary report on residents' cognitive performance and perceptions of the educational environment

The authors describe the implementation of problem-based learning (PBL) in an introductory course to anaesthesiology (ICA) traditionally administered in teacher-centred formats. The study was performed during the 2003 and 2004 courses. Seven residents participated in ICA2003 and 5 in ICA2004. Courses covered pre- and post-anaesthesia care, airway management, pharmacology of anaesthetics, and neuraxial blocks. Lectures, demonstrations and PBL were used in ICA2003. Only PBL was used in ICA2004. ICA2003 residents' perceptions of the contribution of learning formats to solving post-tests were assessed on 100-millimetre visual analogue scales (VASs). Pre-tests, post-tests and the Dundee Ready Education Environment Measure (DREEM) measured outcomes. Pooled mean VAS scores of the perceived contribution of learning formats to the acquisition of knowledge were significantly greater for PBL (81 +/- 13.1 mm) than for lectures (71.96 +/- 16.7 mm) or practical demonstrations (74 +/- 16.9 mm). Pooled mean scores of pre-test and post-tests were 5.21 +/- 2.18 and 8.50 +/- 1.69 in ICA2003 (p < 0.05), and 5.63 +/- 1.83 and 8.98 +/- 1.13 in ICA2004 (p < 0.05), respectively. Pooled pre-test, post-test and DREEM global scores did not differ between courses. PBL may effectively address basic topics in anaesthesiology during intensive learning episodes.     

Psychometric properties of the Dundee Ready Educational Environment Measure (DREEM) applied to medical residents

The Dundee Ready Educational Environment Measure (DREEM) is a measure of students' perceptions of the educational environment, but its performance in evaluating the educational environment in the residency setting has not yet been described. This study aimed at describing the psychometric performance of DREEM applied to medical residents. DREEM was applied to 97 residents from 12 training programs on four specialties in six institutions in three Brazilian cities. Psychometric measures included factor analysis, Cronbach's alpha coefficients, item-to-total correlations, t-test comparisons of scores between genders, institutions, specialties, and programs, correlations with the global score of the Quality of School Life Scale (concurrent validity), and test-retest reliability. Generalizability theory procedures were applied to a random subset of data. Programs (8) were the objects of measure, while institutions (6), specialties (4), raters-within-programs (40), and items-on-the-scale (50) were facets. Variance components, generalizability (G) and dependability (D) coefficients were calculated. Cronbach's alpha was 0.93. DREEM showed high discriminant and concurrent validities. Test-retest reliability was moderate. Interactions between programs, raters and items accounted for 68% of the total variance. G and D coefficients were 0.95 and 0.67, respectively. The instrument proved to be useful for relative comparisons at both resident and program level.     

Lipid Peroxidation in Bariatric Candidates with Nonalcoholic Fatty Liver Disease (NAFLD) – Preliminary Findings

Background: Pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains incompletely known, and oxidative stress is one of the mechanisms incriminated. The aim of this study was to evaluate the role of liver oxidative stress in NAFLD affecting morbidly obese patients. Methods: 39 consecutive patients with BMI >40 kg/m² submitted to Roux-en-Y gastric bypass were enrolled, and wedge liver biopsy was obtained during operation. Oxidative stress was measured by concentration of hydroperoxides (CEOOH) in liver tissue. Results: Female gender was dominant (89.7%) and median age was 43.6 ± 11.1 years. Histology showed fatty liver in 92.3%, including 43.6% with nonalcoholic steatohepatitis (NASH), 48.7% with isolated steatosis and just 7.7% with normal liver. Liver cirrhosis was present in 11.7% of those with nonalcoholic steatohepatitis. Concentration of CEOOH was increased in the liver of patients with NASH when compared to isolated steatosis and normal liver (0.26± 0.17, 0.20± 0.01 and 0.14± 0.00 nmol/mg protein, respectively) (P <0.01). Liver biochemical variables were normal in 92.3% of all cases, and no difference between NASH and isolated steatosis could be demonstrated. Conclusions: 1) Nonalcoholic steatosis, steatohepatitis and cirrhosis were identified in substantial numbers of morbidly obese patients; 2) Concentration of hydroperoxides was increased in steatohepatitis, consistent with a pathogenetic role for oxidative stress in this condition.     

Analysis of the immune response against mixotope peptide libraries from a main antigenic site of foot-and-mouth disease virus

The design of vaccines for RNA viral diseases is complicated by the high genetic variability of the viruses, which favors the selection of escape mutants. A case in point is foot-and-mouth disease virus (FMDV), for which only limited protection has been observed in vaccination with single peptides. We have explored the potential of immunogens of higher sequence diversity, covering a broad range of field or culture-induced mutations at the immunodominant site A of FMDV, serotype C. Four mixotope-type peptide libraries, containing ca. 3 x 10(3) or ca. 3 x 10(5) peptides each, in either linear or cyclic form, and combining most significant mutations found or induced at site A have been synthesized and used to immunize guinea-pigs. Substantial levels of serum conversion have been observed for all four mixotope libraries, as well as for single peptides, linear or cyclic, corresponding to the consensus site A sequence. The specificity and neutralizing ability of the anti-mixotope and -peptide antibodies have been evaluated by direct ELISA and by plaque reduction and micro-neutralization assays, respectively. Challenge experiments with an infectious, guinea-pig-adapted FMDV strain, have shown higher protection rates in animals immunized with the cyclic versions, either in single sequence or in combinatorial mixotope form.     

Cell therapy plus transmyocardial laser revascularization for refractory angina

We describe the use of autologous bone marrow cells combined with transmyocardial laser revascularization in a 74-year-old man with refractory angina. Baseline cardiac magnetic resonance imaging revealed a markedly depressed left ventricle systolic function and an extensive area of myocardial ischemia. During surgery, 11 laser shots using a CO2 Heart Laser System (PLC Medical Systems, Milford, MA) were fired and a 5-mL cell suspension containing 21.5 x 10(6) bone marrow cells/mL was delivered by multiple injections into the myocardium. At 6 months after the procedure, another cardiac magnetic resonance imaging showed an almost complete resolution of the perfusion defect and an improvement in left ventricular contractility.     

In vitro antifungal susceptibilities of Sporothrix schenckii in two growth phases

We have determined the antifungal susceptibilities of 34 clinical isolates of the dimorphic fungus Sporothrix schenckii to 11 drugs using a microdilution method. In general, the type of growth phase (mycelial or yeast) and the temperature of incubation (30 or 35 degrees C) exerted a significant influence on the MICs.     

Presence of Actinobacillus actinomycetemcomitans on the Community Periodontal Index (CPI) teeth in periodontally healthy individuals

The aim of this study was to compare the prevalence of Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) located at Community Periodontal Index (CPI) teeth versus randomly selected teeth to determine if the CPI teeth are representative of this bacteria subgingival colonization in periodontally healthy young individuals. Forty-four individuals between 18 and 27 years of age were included in the study (mean age 23.11 +/- 2.91 years). Pooled subgingival plaque samples were collected with paper points from the mesio-buccal aspect of the CPI teeth (10 teeth for adults and 6 teeth for persons under 20 years of age) and transported in reduced Ringer's solution to the culture medium. Sixty days following the first microbial analysis, new pooled microbial samples were obtained from the mesio-buccal aspect of 10 or 6 randomly selected teeth. The presence of A. actinomycetemcomitans was determined using a selective culture medium. Microbiological data were assessed by the Wilcoxon test (p < 0.05). A border line significance (p=0.51) was observed between CPI teeth and randomly selected teeth in terms of detecting the subgingival occurrence of A. actinomycetemcomitans. CPI teeth showed to be representative of A. actinomycetemcomitans subgingival colonization. Therefore, these results suggest that in periodontally healthy young individuals, CPI teeth could be an appropriate source of samples for the subginginval detection of this pathogen.