Resumo Este trabalho realizou uma apresentação, pela aplicação de um Minicurso, do método de estudo de casos de Harvard como promotor de uma aprendizagem ativa pela aplicação e análise de casos baseados em eventos reais a futuros professores química e outros graduandos da UFCG. Também investigou a viabilidade de utilização dos mapas conceituais e do Facebook como ferramentas de apoio didático ao ensino por meio de casos, mediado pela sala de aula invertida. A temática abordada no caso, estruturado para este estudo, se relacionou ao contexto regional dos próprios discentes. Tanto os Mapas Conceituais como o Facebook apresentaram resultados condizentes com o esperado de suas aplicações.

Abstract This paper presented a mini-course of the Harvard case study method as a promoter of active learning by applying and analyzing cases based on real events to future chemistry professors and other undergraduates of UFCG. It also investigated the feasibility of using conceptual maps and Facebook as tools of didactic support to teaching through cases, mediated by the inverted classroom. The theme addressed in the case, structured for this study, was related to the regional context of the students themselves. Both Conceptual Maps and Facebook presented results consistent with the expected of their applications.

Abstract Pyroligneous extract is applied in diverse areas as an antioxidant, an antimicrobial, and an anti-inflammatory agent. The discovery of new cost-effective antimicrobial agents of natural origin remains a challenge for the scientific community. This study aimed to conduct a systematic review and a technological forecasting of the existent evidence regarding the use of pyroligneous extract as a potential antimicrobial agent. Studies were identified through an investigation of various electronic databases: PubMed, SciFinder, Web of Science, Scopus, Scielo, Google scholar, and ProQuest. Patents were searched through INPI, Google patents, Espacenet, Patents online, USPTO, and WIPO. The literature on antimicrobial activity of pyroligneous extract are limited given the short duration of studies and variability in study design, use of pyroligneous preparations, and reports on results. However, evidence suggests the potential of pyroligneous extract as a natural antimicrobial agent. The most studied activity was the role of PE as a food preservative. However, pyroligneous extracts are also effective against pathogenic bacteria in the oral microflora and treatment of candidal infections. Further research is needed using standardized preparations of pyroligneous extracts to determine their long-term effectiveness and ability as antimicrobial agents.

Eudragit® RS100 microspheres of two chalcones were prepared by solvent evaporation technique. A simple and rapid high-performance liquid chromatography (HPLC) method was developed and validated to determine the encapsulation efficiency, drug loading and release profiles of these chalcones in a microparticulate system. The mean EE values for the two chalcones-loaded microparticles were 98.8 ± 1.3% and 99.5 ± 0.9%. Scanning electron microscope (SEM) studies showed that one chalcone-loaded microspheres are spherical and smooth appearance whereas the other chalcone-loaded microspheres showed irregular particles and a rough surface. The analysis of the second chalcone by thermogravimetric analysis (TGA) showed a higher thermal stability compared to the first chalcone. Drug release profiles were determined at pH 7.4 phosphate buffered saline (100 mmol L-1) with sodium lauryl sulfate (0.5%). The systems prepared with Eudragit® showed 78 and 95% of the two chalcones were released after 24 hours. The experimental results indicated that the prepared polymeric microspheres may be useful for potential applications.

Gene therapy is a promising tool for the treatment of ocular diseases. Nevertheless, there are some import limitations, especially related to the ocular route and the characteristics of nucleic acids that must be overcome to ensure the success of the therapy. In this context, nanotechnology-based carriers such as nanoemulsions, nanoparticles, dendrimers and liposomes have risen as a promising vehicle for the protection of genetic material for vectoring the target cells. The success of such approach is closely related to the judicious selection of the biomaterial, where chemical structure and intermolecular interactions play a major role. So, this manuscript reviews some of the most important biomaterials, lipid and polymeric origin, employed in the manufacture of nanotechnologic carriers for ocular gene therapy involving interfering RNA (siRNA), antisense oligonucleotide (AS-ON) and plasmid DNA (pDNA).

ABSTRACTThe aim of this study is to investigate the effect of Cecropia glaziovii Snethl, Urticaceae, extracts on the oral glucose tolerance curve, on glycemia in alloxan-induced diabetic rats and vasorelaxant effect after the extraction process, and to standardize the extractive solutions. The effects of the process variables and their interactions were calculated in relation to dry residue, pH, total phenolic results and chemical marker content. Furthermore, the effect of the extracts (400 mg/kg), chlorogenic (2 or 15 mg/kg) and caffeic acids (2 mg/kg) were investigated on the oral glucose tolerance curve and on glycemia in alloxan-induced diabetic rats. Oral administration of ethanol extracts 4d20 and 8d20 significantly improved glucose tolerance in the hyperglycemic rats. Chlorogenic and caffeic acids, as well as the association of the compounds were able to significantly reduce glycemia after oral gavage treatments. On the other hand, the aqueous extracts did not alter the glycemia. The aqueous extracts (8020 and 9030) and only the higher dose of chlorogenic acid presented a significant effect on serum glucose lowering in diabetic rats. Additionally, the IC50 reveals that the ethanol extracts presented more potent vasodilator effects than the aqueous extracts in aortic rings. This study shows that C. glazioviistandardized extracts exhibits antihyperglycemic action, is able to improve glucose tolerance and has a potent vascular relaxing effect. These results are probably linked to concentrations of the main phenolic compounds of the extracts.

This study analyses the contribution of a problem-situation approach linked to teaching tools for the teaching of the concepts of ionic bonding and metallic bonding. Students of chemistry of the Federal Rural University of Pernambuco in Brazil participated in the study. The methodology involved: i) developing a problem-situation; ii) a didactic intervention that made use of theoretical classes, simulations, videos and hypermedia; and iii) manual preparation of crystal lattices with use of styrofoam bails and toothpicks. The results showed that the students were able to identify the electrostatic nature of the chemical bonds, correctly classified the type of chemical bond and represented the crystal structures of ionic and metallic compounds, as expected. However some alternative conceptions were identified. For example, the association of the strong bond to the ionic compounds compared to metallic substances.

Este estudio analiza la contribución de una situación-problema vinculada a instrumentos didácticos para la enseñanza de ios conceptos de enlace iónico y enlace metálico. Participaron estudiantes de química de la carrera de Licenciatura en Química de la Universidad Federal Rural de Pernambuco en Brasil. La metodología incluyó: i) elaboración de una situación-problema; ii) intervención didáctica que hizo uso de clases teóricas, simulación, vídeos e hipermedia; y iii) confección manual de retículos cristalinos con uso de bolas de poliestireno y mondadientes. Los resultados mostraron que los estudiantes fueron capaces de identificar la naturaleza electrostática de los enlaces químicos, clasificaron correctamente el tipo de enlace químico y representaron como se esperaba las estructuras cristalinas de compuestos iónicos y metálicos. Sin embargo, se identificaron algunas concepciones alternativas, por ejemplo, la asociación de un enlace fuerte a los compuestos iónicos en comparación con las sustancias metálicas.

Cecropia glaziovi Snethl., Urticaceae, is commonly used in South America and is one of the species included in the Brazilian Medicinal Plants Research Program. Pharmacological studies have led to reports of the potential of C. glaziovi as a hypotensive, antiasthmatic and anxiolytic agent. The strict requirements regarding the quality, safety and effectiveness of phytopharmaceutical products represent an enormous challenge in the search for products with a high level of uniformity, reproducibility and stability. The incorporation of dry extracts into multiparticulate dosage forms, such as pellets produced by extrusion/spheronization technology, is a suitable alternative to overcome the lack of technological properties of dry extracts, since they are associated with low flowability and high hygroscopicity. In this study, an optimized dry extract (ODE) of C. glaziovi was incorporated into pellets seeking to decrease the moisture sorption and increase the stability, safety and percentage of the extract in the final product. Pellets containing around 50% of ODE were considered the most technologically viable, offering a narrow particle size distribution, significant improvement in the flowability and compressibility properties, and decrease in the moisture compared with the ODE. In conclusion, pellets containing a high dose of the C. glaviovi extract were successfully prepared, achieving degrees of quality, physical stability and feasibility compatible with the desirable characteristics of a phytopharmaceutical.

OBJETIVO: Avaliar os fatores associados à presença de RNA-HIV na vagina. MÉTODOS: Estudo de corte transversal, em mulheres infectadas por HIV, excluindo-se aquelas com antecedente de histerectomia, as em uso de medicações vaginais nas últimas 48 horas, as que se referiram à relação sexual desprotegida há menos de 72 horas, as gestantes e aquelas com sangramento genital. Após consentimento, coletou-se amostra sanguínea para contagem de linfócitos T CD4 e carga viral plasmática de HIV, além de lavado vaginal com 10mL de solução salina, que foi centrifugado, aliquotado e armazenado em freezer -70°C para posterior quantificação de RNA-HIV livre. A mensuração de carga viral de RNA-HIV livre plasmática e vaginal foi realizada utilizando-se o kit HIV Monitor v1.5 Cobas Amplicor®, Roche. Pesquisou-se a presença de HPV de alto e baixo risco, clamídia e gonococo por Captura Híbrida II®, Digene, em amostra endocervical. Colheu-se amostra vaginal para bacterioscopia com coloração de Gram, utilizando-se os critérios de Nugent. RESULTADOS: Entre as 200 mulheres estudadas, 73,5% usavam terapia anti-retroviral (TARV) com drogas múltiplas. O RNA-HIV foi detectável no lavado vaginal de 18 delas (9%), mas em apenas uma daquelas que tinham carga viral plasmática indetectável (0,5%). A prevalência de HIV vaginal foi 24 vezes maior naquelas em que HIV plasmático era detectável. Carga viral plasmática de HIV, não usar TARV, CD4 reduzido e vaginose bacteriana aumentaram a prevalência de RNA-HIV vaginal, mas apenas a carga viral plasmática se manteve significativa na análise ajustada. CONCLUSÃO: A prevalência de RNA-HIV vaginal foi baixa (9%). A carga viral acima de 1.500 cópias/mL foi a única variável que permaneceu como fator de risco para RNA-HIV vaginal livre.

OBJECTIVE: To evaluate factors associated to presence of free RNA-HIV in the vagina. METHODS: Cross-sectional study with HIV-infected women, excluding those who had undergone histerectomy, had used vaginal medication within the last 48 hours, had had unprotected sex less than 72 hours before, were pregnant, or had genital bleeding. After signing an informed consent, blood samples were obtained for T CD4 lymphocytes count and plasmatic viral load, in addition to cervico-vaginal lavage using 10mL of sterile normal saline, later centrifuged, aliquoted and stored at - 70°C to quantify free HIV-RNA. Plasmatic and vaginal viral load were measured using the kit HIV Monitor v1.5 Cobas Amplicor, Roche. Hybrid Capture test Digene was utilized for HPV (high and low risk), clamydia trachomatis and N. gonorrhoae detection from an endocervical sample. Vaginal swab for bacterioscopy by the Gram method, evaluated according to Nugent criteria was obtained. RESULTS: Among 200 women evaluated, 73.5% were using HAART. The RNA-HIV was detectable in the vaginal lavage of 18 (9%), but in only one of those who had undetectable plasma viral load (0.5%). The vaginal prevalence of HIV was 24 times higher among those with detectable plasmatic HIV. Plasma viral load > 1500 copies/mL, no HAART use, reduced CD4 and bacterial vaginosis had increased prevalence of vaginal HIV-RNA, but in the adjusted statistical analysis, only the former remained significant CONCLUSION: Prevalence of vaginal HIV-RNA was low (9%). Plasmatic viral load > 1500 copies/mL, was the only risk factor for free vaginal HIV-RNA.

Resumo: Este artigo retrata uma pesquisa realizada com um grupo de professores de química do ensino médio no sentido de investigar como eles concebem a abordagem por competências na escola. A metodologia envolveu as seguintes etapas: (i)- concepções dos(as) professores(as) sobre competência, usando como instrumento de pesquisa um questionário; (ii)- análise e validação das respostas dos(as) professores(as) ao questionário; (iii)- discussão sobre competência na escola, utilizando como instrumentos um texto e uma fita de vídeo de Perrenoud. Os resultados mostraram que não há uma mobilização dos(as) professores(as) e das escolas com relação à abordagem por competências. Além disso, esta abordagem será possível se o sistema educacional investir em melhores salários, recursos, e uma formação continuada inserida no projeto pedagógico que propicie a cooperação entre os(as) professores(as) e a universidade e contribua para a discussão dos conteúdos de química, metodologia e avaliação. E, ao mesmo tempo, a construção de novas competências profissionais nos(as) professores(as).

Abstract: This paper reports a research carried out chemistry teachers group of high school education in order to investigate as they conceive the approaching by competencies in the school. The methodology involved the following stages: conceptions of the teachers about competence, using as research instrument a questionnaire; it analyses and validation of the answers of the teachers to the questionnaire; discussion about competence in the school, using as instruments a Perrenoud's text and video. The results showed that there is not mobilization of the teachers and schools to relation with approaching of competencies. Besides that, this approaching will be possible if the educational system to be concerned salary best, recourses, available time and a continued formation introduced in the school pedagogical project, that propitiate the cooperation between teachers and university and contribute to the discussion about chemistry subjects, methodology and evaluation. And, the same time, the construction of the news professional competencies in the teachers.

Açúcares redutores e matéria seca são características muito importantes em batata para processamento. Duas espécies de batata silvestre, Solanum commersonii, subespécies commersonii e malmeanum, e S. chacoense, subespécie muelleri, ocorrem no Sul do Brasil. Essas espécies são importantes para programas de melhoramento, pois apresentam variabilidade para diversas características importantes, tais como, tolerância à seca e geada, resistências a doenças e insetos e teor de matéria seca. Os objetivos deste trabalho foram verificar a variabilidade genética e estimar a herdabilidade para teor de açúcares redutores em clones de batata silvestre, que ocorrem no Sul do Brasil. Cinqüenta clones de batata silvestre, tomados ao acaso, da coleção mantida na EMBRAPA - Clima Temperado foram cultivados, sob telado, no outono e na primavera de 1996. No outono, 30 e, na primavera, 40 clones produziram tubérculos para análise de açúcares redutores. Os teores de açúcares redutores dos tubérculos foram determinados pelo método de Lane Enyon e identificados pelo método de Somogyi, modificado por NELSON (1944). Os resultados indicaram que as espécies estudadas apresentam variabilidade para teor de açúcares redutores, com alta herdabilidade, principalmente no outono.

Reducing sugar and dry matter are very important traits in potatoes for processing. Two wild potato species, Solanum commersonii, subspecies commersonii and malmeanum, and S. chacoense, subspecie mu, occur in the South of Brazil. These species are important for breeding programs, since they have variability for several important traits, such as drought and frost resistance, disease and insect resistance, and dry matter content.. The objectives of this research were to verify the genetic variability for reducing sugar content in wild potato clones of species that occur in this region and to estimate its heritability. Fifty wild potato clones, aleatorily chosen, of Embrapa Clima Temperado collection were grown in screen house, in autumn and spring season of 1996. In autumn, 30 and, in spring, 40 clones produced tubers for the reducing sugar analysis. Tuber sugar content was determined by using the Lane Enyon method and identified by the Somogyi method, modified by NELSON (1944). The results indicated that these species have genetic variability for reducing sugars, with high heritability, mainly in the fall season.

O objetivo deste trabalho foi avaliar o teor de açúcares redutores e totais, em tubérculos de batata de germoplasma selecionado do programa de melhoramento da Embrapa Clima Temperado. Dezoito cultivares e clones, e duas cultivares de indústria (Atlantic e Bintje, testemunhas) foram avaliadas neste estudo. O experimento foi conduzido no outono de 1994, em Pelotas, RS. A concentração de açúcares redutores nos tubérculos dos 20 genótipos variou de 0,21% a 1,71%. O clone C-1582-25-90 e a cultivar Cerrito Alegre apresentaram teores mais baixos de açúcares redutores do que as testemunhas, sem, no entanto, diferirem significativamente destas. Os outros clones e cultivares testados também não diferiram da Atlantic. Estes resultados indicam que no germoplasma da Embrapa Clima Temperado existem genótipos com teor de açúcares redutores semelhante ao dos genótipos utilizados pelas indústrias brasileiras de processamento de batata. Entretanto, nenhum deles apresenta baixo teor de açúcares redutores. A concentração de açúcares totais foi mais baixa nos tubérculos das cultivares Cristal e Macaca, e do clone C-1582-25-90, sem diferir significativamente das testemunhas.

The objective of this work was to evaluate the reducing and total sugar content in potato tubers of selected germplasm of the Embrapa Clima Temperado breeding program. Eighteen cultivars and clones and two processing cultivars (Atlantic e Bintje, checks) were evaluated in this study. The experiment was carried out during de fall season of 1994, in Pelotas, RS. The reducing sugar concentration in the tubers of the 20 genotypes varied from 0,21% to 1,71%. The clone C-1582-25-90 and the cultivar Cerrito Alegre had lower reducing sugar content than the check cultivars, however, without, differing significantly from them. The other tested clones and cultivars also did not differ from ‘Atlantic’. These results indicate that in the Embrapa Clima Temperado germplasm there are genotypes with reducing sugar content similar to those used by the brazilian potato processing industry. However, none of them has low reducing sugar content. The total sugar content was lower in the tubers of Cristal and Macaca cultivars, and of C-1582-25-90 clone, without differing significantly from the checks.