Students' perception of animal or virtual laboratory in physiology practical classes in PBL medical hybrid curriculum.

Over the years, much criticism against animal use for physiology teaching has been made. Hence, replacement by suitable alternatives has increased in several pedagogical approaches. This study examined students' perceptions of animal versus virtual (video/computer) laboratory classes in physiological sciences associated with the effectiveness of the problem-based learning (PBL) hybrid curriculum. Three cohorts of medical students from the University of Ribeirão Preto, who participated in animal or virtual physiology classes or both, were asked to fill out a 5-point Likert questionnaire about knowledge acquisition/motivation, importance to PBL learning goals, skills acquired, need for animal use, academic formation, learning impairment, and alternative methods. We also assessed their grades in the final exam. A total of 350 students were included, in which 108 participated only in virtual classes, 120 only in practical animal laboratory classes, and 122 in both approaches. The majority agreed that the two methods improved their knowledge acquisition/motivation and helped to reinforce tutorial goals and to acquire skills. However, the cohort who experienced both approaches favored animal laboratory. Students believe animal use is needed and did not impair their learning. Conversely, their opinion about academic formation without animal laboratory classes was divided, as was whether this approach inspired them to seek alternative methods. Despite the different perceptions, there was no difference among the groups' final grades (7.3 ± 1 vs. 7.2 ± 1 vs. 7.2 ± 2 for virtual or practical animal laboratory classes or both, respectively). Therefore, virtual activities are not as effective as animal use in the opinions of the students, but they are successful strategies in physiology learning that can be used in practical classes in a hybrid PBL curriculum.

Formative assessment scores in tutorial sessions correlates with OSCE and progress testing scores in a PBL medical curriculum.

BACKGROUND: Effective assessments programs are a challenge in problem-based learning (PBL). One of the main principles of this educational setting is the Formative Assessment (FA). We hypothesized that students' performance assessed by FA in tutorial sessions in a PBL curriculum is related to other summative assessments. OBJECTIVE: To investigate the correlation among FA in tutorial sessions with grades obtained in Objective Structured Clinical Evaluation (OSCE) and Progress Testing (PT) to better understand the assessment process in PBL medical teaching approach and to predict student's future performance. DESIGN: An observational cross-sectional study was conducted comparing FA, OSCE and PT scores from 4th to 8th semester medical students. Correlation analyses were performed using pooled and separate data from the 4th and 8th semesters. RESULTS: From the 5th to 8th semester, OSCE scores were smaller compared to the FA, while PT scores were lower in all stages. In the pooled data, the correlation analysis showed a significant positive relationship between grades on FA and OSCE, FA and PT and OSCE and PT. A significant correlation among the three assessments strategies was also detected in the 8th semester, but not in the 4th semester. CONCLUSIONS: Assessment strategies in PBL approach, including FA, OSCE and PT, have positive correlations, which increases as the medical course becomes more complex.

Assessment test before the reporting phase of tutorial session in problem-based learning.

PURPOSE: In our context, problem-based learning is not used in the preuniversity environment. Consequently, students have a great deal of difficulty adapting to this method, particularly regarding self-study before the reporting phase of a tutorial session. Accordingly, the aim of this study was to assess if the application of an assessment test (multiple choice questions) before the reporting phase of a tutorial session would improve the academic achievement of students at the preclinical stage of our medical course. METHODS: A test consisting of five multiple choice questions, prepared by tutors of the module at hand and related to the problem-solving process of each tutorial session, was applied following the self-study phase and immediately before the reporting phase of all tutorial sessions. The questions were based on the previously established student learning goals. The assessment was applied to all modules from the fifth to the eighth semesters. The final scores achieved by students in the end-of-module tests were compared. RESULTS: Overall, the mean test score was 65.2±0.7% before and 68.0±0.7% after the introduction of an assessment test before the reporting phase (P<0.05). Students in the sixth semester scored 67.6±1.6% compared to 63.9±2.2% when they were in the fifth semester (P<0.05). Students in the seventh semester achieved a similar score to their sixth semester score (64.6±2.6% vs 63.3±2%, respectively, P>0.05). Students in the eighth semester scored 71.8±2.3% compared to 70±2% when they were in the seventh semester (P>0.05). CONCLUSION: In our medical course, the application of an assessment test (a multiple choice test) before the reporting phase of the problem-based learning tutorial process increases the overall academic achievement of students, especially of those in the sixth semester in comparison with when they were in the fifth semester.

An algorithm to classify amino acid sequences into protein groups of Bothrops jararacussu venomous gland.

An algorithm for automatic clustering of database protein sequences from Bothrops jararacussu venomous gland, according to sequence similarities of their domains, is described. The program was written in C and Perl languages. This algorithm compares a domain with each ORF protein sequence in the database. Each nucleotide FASTA sequence generates six ORFs. As a result, the user has a list containing all sequences found in a specific domain and a display of the sequence, domain and number of hits. The algorithm lists only the sequences that present a minimum similarity of 30 hits and the best alignment. This limit was considered appropriate. The algorithm is available in the Internet (www.compbionet.org.br/cgi-domains/homesnake) and it can quickly and accurately organizes large database into classes.

Brazilian medical students' perceptions of expert versus non-expert facilitators in a (non) problem-based learning environment.

BACKGROUND: In problem-based learning (PBL), the facilitator plays an important role in guiding the student learning process. However, although content expertise is generally regarded as a useful but non-essential prerequisite for effective PBL facilitation, the perceived importance of content knowledge may be subject to cultural, contextual, and/or experiential influences. AIM: We sought to examine medical students' perceptions of subject-matter expertise among PBL facilitators in a region of the world (Brazil) where such active learning pedagogies are not widely used in university or pre-university settings. RESULTS: Of the 252 Brazilian medical students surveyed, significantly (p≤0.001) greater proportions viewed content expert facilitators to be more effective than their non-expert counterparts at building knowledge (95% vs. 6%), guiding the learning process (93% vs. 7%), achieving cognitive learning (92% vs. 18%), generating learning goals (87% vs. 15%), and motivating self-study (80% vs. 15%). DISCUSSION/CONCLUSION: According to Brazilian medical students, subject-matter expertise among PBL facilitators is essential to the learning process. We believe this widespread perception is due, in large part, to the relative lack of prior educational exposure to such pedagogies.

Analysis of Bothrops jararacussu venomous gland transcriptome focusing on structural and functional aspects: I--gene expression profile of highly expressed phospholipases A2.

Snake venom glands are a rich source of bioactive molecules such as peptides, proteins and enzymes that show important pharmacological activity leading to in local and systemic effects as pain, edema, bleeding and muscle necrosis. Most studies on pharmacologically active peptides and proteins from snake venoms have been concerned with isolation and structure elucidation through methods of classical biochemistry. As an attempt to examine the transcripts expressed in the venom gland of Bothrops jararacussu and to unveil the toxicological and pharmacological potential of its products at the molecular level, we generated 549 expressed sequence tags (ESTs) from a directional cDNA library. Sequences obtained from single-pass sequencing of randomly selected cDNA clones could be identified by similarities searches on existing databases, resulting in 197 sequences with significant similarity to phospholipase A(2) (PLA(2)), of which 83.2% were Lys49-PLA(2) homologs (BOJU-I), 0.1% were basic Asp49-PLA(2)s (BOJU-II) and 0.6% were acidic Asp49-PLA(2)s (BOJU-III). Adjoining this very abundant class of proteins we found 88 transcripts codifying for putative sequences of metalloproteases, which after clustering and assembling resulted in three full-length sequences: BOJUMET-I, BOJUMET-II and BOJUMET-III; as well as 25 transcripts related to C-type lectin like protein including a full-length cDNA of a putative galactose binding C-type lectin and a cluster of eight serine-proteases transcripts including a full-length cDNA of a putative serine protease. Among the full-length sequenced clones we identified a nerve growth factor (Bj-NGF) with 92% identity with a human NGF (NGHUBM) and an acidic phospholipase A(2) (BthA-I-PLA(2)) displaying 85-93% identity with other snake venom toxins. Genetic distance among PLA(2)s from Bothrops species were evaluated by phylogenetic analysis. Furthermore, analysis of full-length putative Lys49-PLA(2) through molecular modeling showed conserved structural domains, allowing the characterization of those proteins as group II PLA(2)s. The constructed cDNA library provides molecular clones harboring sequences that can be used to probe directly the genetic material from gland venom of other snake species. Expression of complete cDNAs or their modified derivatives will be useful for elucidation of the structure-function relationships of these toxins and peptides of biotechnological interest.

Identification and complete sequencing of novel human transcripts through the use of mouse orthologs and testis cDNA sequences.

The correct identification of all human genes, and their derived transcripts, has not yet been achieved, and it remains one of the major aims of the worldwide genomics community. Computational programs suggest the existence of 30,000 to 40,000 human genes. However, definitive gene identification can only be achieved by experimental approaches. We used two distinct methodologies, one based on the alignment of mouse orthologous sequences to the human genome, and another based on the construction of a high-quality human testis cDNA library, in an attempt to identify new human transcripts within the human genome sequence. We generated 47 complete human transcript sequences, comprising 27 unannotated and 20 annotated sequences. Eight of these transcripts are variants of previously known genes. These transcripts were characterized according to size, number of exons, and chromosomal localization, and a search for protein domains was undertaken based on their putative open reading frames. In silico expression analysis suggests that some of these transcripts are expressed at low levels and in a restricted set of tissues.

The generation and utilization of a cancer-oriented representation of the human transcriptome by using expressed sequence tags.

Whereas genome sequencing defines the genetic potential of an organism, transcript sequencing defines the utilization of this potential and links the genome with most areas of biology. To exploit the information within the human genome in the fight against cancer, we have deposited some two million expressed sequence tags (ESTs) from human tumors and their corresponding normal tissues in the public databases. The data currently define approximately 23,500 genes, of which only approximately 1,250 are still represented only by ESTs. Examination of the EST coverage of known cancer-related (CR) genes reveals that <1% do not have corresponding ESTs, indicating that the representation of genes associated with commonly studied tumors is high. The careful recording of the origin of all ESTs we have produced has enabled detailed definition of where the genes they represent are expressed in the human body. More than 100,000 ESTs are available for seven tissues, indicating a surprising variability of gene usage that has led to the discovery of a significant number of genes with restricted expression, and that may thus be therapeutically useful. The ESTs also reveal novel nonsynonymous germline variants (although the one-pass nature of the data necessitates careful validation) and many alternatively spliced transcripts. Although widely exploited by the scientific community, vindicating our totally open source policy, the EST data generated still provide extensive information that remains to be systematically explored, and that may further facilitate progress toward both the understanding and treatment of human cancers.

A transcript finishing initiative for closing gaps in the human transcriptome.

We report the results of a transcript finishing initiative, undertaken for the purpose of identifying and characterizing novel human transcripts, in which RT-PCR was used to bridge gaps between paired EST clusters, mapped against the genomic sequence. Each pair of EST clusters selected for experimental validation was designated a transcript finishing unit (TFU). A total of 489 TFUs were selected for validation, and an overall efficiency of 43.1% was achieved. We generated a total of 59,975 bp of transcribed sequences organized into 432 exons, contributing to the definition of the structure of 211 human transcripts. The structure of several transcripts reported here was confirmed during the course of this project, through the generation of their corresponding full-length cDNA sequences. Nevertheless, for 21% of the validated TFUs, a full-length cDNA sequence is not yet available in public databases, and the structure of 69.2% of these TFUs was not correctly predicted by computer programs. The TF strategy provides a significant contribution to the definition of the complete catalog of human genes and transcripts, because it appears to be particularly useful for identification of low abundance transcripts expressed in a restricted set of tissues as well as for the delineation of gene boundaries and alternatively spliced isoforms.