ResumoOs conteúdos apresentados na disciplina de Bioquímica exigem conhecimentos científicos prévios e são, muitas vezes, descontextualizados e fragmentados, impedindo um significado para o aprendizado. O artigo relata a experiência com o uso de uma metodologia alternativa no ensino de Bioquímica: Mapas Conceituais. O desenho procedimental baseou-se no uso de questões objetivas com questionários conceituais antes e após a leitura do Mapa Conceitual desenvolvido a partir de tema estudado na disciplina de Bioquímica do curso de Odontologia da UFF (RJ). O tema Integração do Metabolismo, consenso entre os docentes como capaz de relacionar diferentes conceitos, foi escolhido para elaboração do Mapa.Objetivou-se demonstrar que tal ferramenta de ensino pode permitir integração de conceitos. Os resultados mostraram que, após o uso do Mapa, o número de alunos que acertou grande parte ou todas as questões propostas no questionário foi consideravelmente maior, sugerindo Aprendizagem Significativa. Palavras-chave: Metodologias de ensino; Ensino de Bioquímica; Mapas conceituais. AbstractThe contents of Biochemistry discipline require previous scientific knowledge and it is often disconnected and fragmented, voiding a meaningful learning. This article describes an experience with the use of an alternative methodology to teach Biochemistry: Concept Maps. The procedural design was based on the use of subject questionnaires before and after reading the Concept Map developed from a subject studied in Biochemistry during the graduation program for the dental school of UFF (RJ, Brazil). Integration of Metabolism is consensus among teachers as a topic able to effectively correlate different concepts as it has been chosen to prepare the Map. The aim of this study was to show this teaching tool that might allow concepts' integration. The results showed, after using the Map, a higher number of students getting right answers to all proposed questions, suggesting improvement in Significant Learning.

Resistance expression can occur as a consequence of irrational use of antibiotics, since this implies dissemination of subinhibitory concentration (sub-MICs) in different environments and generates a selective pressure. The study aimed to evaluate the in vitro influence of selective pressure on antibiotic resistance expression in two oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA), through exposure to oxacillin sub-MICs. One heteroresistant OS-MRSA strain and a non-heteroresistant strain, both isolated from nasal colonization were exposed to two-fold serial dilutions of oxacillin (0,125 a 256 μg/mL) during seven consecutive days. Disc diffusion test was used to determine the susceptibility to several antibiotics and population analysis profile (PAP) was used to evaluate the expression of oxacillin resistance before and after antibiotic exposure. Susceptibility to non-β-lactam antibiotics was not altered but changes in phenotypic expression of penicillin and oxacillin resistance were observed. Both OS-MRSA strains began to express homoresistance (oxacillin MIC = 256 μg/mL) and had no penicillin zone inhibition after induction, different from that was observed before oxacillin exposure, which suggested increased in β-lactamase production. In vitro selective pressure with oxacillin stimulated β-lactamase production and led phenotypic expression of oxacillin resistance in heteroresistant and non-heteroresistant OS-MRSA, which became homoresistant. This reinforces the impact that irrational use of antibiotics has on individuals colonized by S. aureus and on the population, emphasizing that the emergence and spread of resistance to antibiotics represent a process of evolution in response to selective antimicrobial pressure.

Human blood is sterile. When there is an infection, microorganisms can reach the bloodstream, which is known as bacteremia. This can be detected by blood culture. To study the prevalence of microorganisms isolated from blood culture samples. One hundred thirty-seven blood cultures were collected from hospitalized patients. All blood samples were processed for culture using a BACT/Alert blood culture machine. Further identification of bacterial pathogens and their antimicrobial susceptibility test were performed using standard microbiological procedures.Among these samples, 20.44% had a positive culture, 60.71% of which belonged to females and 39.29% were from male patients. The most common microorganisms found in positive blood cultures were coagulase negative Staphylococcus (33.33%), Staphylococcus aureus (23.33%), Klebsiella pneumoniae (6.70%), and Escherichia coli (6.66%). One sample showed an ESBL-producing E. coli. Gram-positive microorganisms were 100% susceptible to vancomycin and displayed considerable resistance to oxacillin. Many Gram-negative bacteria were resistant to cephalosporins.