29 resultados para teaching chemistry


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The palladium catalyzed cross-coupling reaction of phenyltrifluoroborate with a chemoenzymatically derived bromoazidoconduritol, combined with 1,3-dipolar cycloaddition, with a variety of alkynes is described. Fourteen new compounds were synthesized in moderate to good yields. The click chemistry reaction can be effected by using sodium ascorbate and CuSO(4) center dot 5H(2)O as catalyst in toluene-H(2)O at room temperature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this work is to present a simple, practical and efficient protocol for drug design, in particular Diabetes, which includes selection of the illness, good choice of a target as well as a bioactive ligand and then usage of various computer aided drug design and medicinal chemistry tools to design novel potential drug candidates in different diseases. We have selected the validated target dipeptidyl peptidase IV (DPP-IV), whose inhibition contributes to reduce glucose levels in type 2 diabetes patients. The most active inhibitor with complex X-ray structure reported was initially extracted from the BindingDB database. By using molecular modification strategies widely used in medicinal chemistry, besides current state-of-the-art tools in drug design (including flexible docking, virtual screening, molecular interaction fields, molecular dynamics. ADME and toxicity predictions), we have proposed 4 novel potential DPP-IV inhibitors with drug properties for Diabetes control, which have been supported and validated by all the computational tools used herewith.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: To describe an outbreak of imipenem-resistant metallo-beta-lactamase-producing Pseudomonas aeruginosa, enzyme type bla, by horizontal transmission in patients admitted to a mixed adult ICU. Methods: A case-control study was carried out, including 47 patients (cases) and 122 patients (control) admitted to the mixed ICU of a university hospital in Minas Gerais. Brazil from November 2003 to July 2005. The infection site, risk factors, mortality, antibiotic susceptibility, metallo-beta-lactamase (MBL) production, enzyme type, and clonal diversity were analyzed, Results: A temporal/spatial relationship was detected in most patients (94%), overall mortality was 55.3%, and pneumonia was the predominant infection (85%). The majority of isolates (95%) were resistant to imipenem and other antibiotics, except for polymyxin, and showed MBL production (76.7%). Only bla SPM-1 (33%) was identified in the 15 specimens analyzed. In addition, 4 clones were identified, with a predominance of clone A (61.5%) and B (23.1%). On multivariate analysis, advanced age, mechanical ventilation, tracheostomy, and previous imipenem use were significant risk factors for imipenem-resistant P. aeruginosa infection. Conclusions: Clonal dissemination of MBL-producing P. aeruginosa strains with a spatial/temporal relationship disclosed problems in the practice of hospital infection control, low adherence to hand hygiene, and empirical antibiotic use. (C) 2008 Elsevier Espana, S.L. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article examines the subject matter of learning within the context of information society, through an inquiry concerning both the reforms in education adopted in Brazil in the last thirty years and their results. It provides a revision on the explanations of school failure based on assumptions of learning problems due to cognitive and linguistic deficits. From the guidelines related with written school forms as well as the constant cultural oppression accomplished inside the school, the article claims the necessity of changing the psychological and pedagogic views that, under the label of democratic practices, determine school institutions and its daily life, by means of instrumental relations with knowledge that disregard the reading practices which are congenial to popular culture.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Radical anions are present in several chemical processes, and understanding the reactivity of these species may be described by their thermodynamic properties. Over the last years, the formation of radical ions in the gas phase has been an important issue concerning electrospray ionization mass spectrometry studies. In this work, we report on the generation of radical anions of quinonoid compounds (Q) by electrospray ionization mass spectrometry. The balance between radical anion formation and the deprotonated molecule is also analyzed by influence of the experimental parameters (gas-phase acidity, electron affinity, and reduction potential) and solvent system employed. The gas-phase parameters for formation of radical species and deprotonated species were achieved on the basis of computational thermochemistry. The solution effects on the formation of radical anion (Q(center dot-)) and dianion (Q(2-)) were evaluated on the basis of cyclic voltammetry analysis and the reduction potentials compared with calculated electron affinities. The occurrence of unexpected ions [Q + 15](-) was described as being a reaction between the solvent system and the radical anion, Q(center dot-).The gas-phase chemistry of the electrosprayed radical anions was obtained by collisional-induced dissociation and compared to the relative energy calculations. These results are important for understanding the formation and reactivity of radical anions and to establish their correlation with the reducing properties by electrospray ionization analyses.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Protein engineering is a powerful tool, which correlates protein structure with specific functions, both in applied biotechnology and in basic research. Here, we present a practical teaching course for engineering the green fluorescent protein (GFP) from Aequorea victoria by a random mutagenesis strategy using error-prone polymerase chain reaction. Screening of bacterial colonies transformed with random mutant libraries identified GFP variants with increased fluorescence yields. Mapping the three-dimensional structure of these mutants demonstrated how alterations in structural features such as the environment around the fluorophore and properties of the protein surface can influence functional properties such as the intensity of fluorescence and protein solubility.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article analyzes traditions of debate about the teaching of history in Brazil since the 1964-1984 dictatorship. It discusses the changes, continuities, achievements and losses in the history of the discipline. It emphasizes the importance of school culture, the necessary continuity of the school as an institution and dialogue with non-school forms of education.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: This study evaluates whether a course that was designed for first-year psychiatric residents and that specifically addressed psychodynamic principles fostered residents` progress in knowledge, skills, and attitudes regarding these concepts. Methods: The course was given in the 2005 academic year to all residents (N = 18) in their first psychiatric postgraduate year at the Department and Institute of Psychiatry, University of Sao Paulo, Brazil. The residents were assessed in the first and last sessions of the course through a written test that was blindly rated by two independent judges. Residents were also interviewed to observe whether psychodynamic concepts had been integrated into actual practice. Their responses were subjected to content analysis. Significance was tested using analysis of variance or nonparametric tests when necessary. Agreement between the judges was tested using intraclass correlation coefficients. Results: The judges demonstrated a high level of agreement. The difference in mean scores before and after the course was such that the total score increased by a mean of 2.5 points (total test score was 10 points). Additionally, residents started to undergo personal psychotherapy after the course. They reported that this course had markedly improved their relationship with patients. They emphasized the opportunities for self-reflection and gaining insights into themselves and patient treatment issues. Conclusion: This initial study indicates that this educational method can effectively promote psychodynamic knowledge, skills, and appropriate attitudes for managing psychiatric outpatients among residents. The course was very well received by the residents, and a similar method can easily be instituted within other residency programs that pursue integrated teaching methods.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

It was developed a teaching tool in Dermatology for undergraduate medical students, using an interactive website, the Cybertutor. Clinical cases, lectures and updated bibliography were selected. Photographies of dermatological lesions were taken from ambulatory patients. The topics of the lectures were based on the current curriculum of the Federal University of Rio Grande do Sul. The Cybertutor is a dynamic and modern teaching tool, allowing constant innovation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: to describe women`s feelings about mode of birth. Design: exploratory descriptive design. Semi-structured interviews were conducted using a questionnaire that had been developed previously (categorical data and open-and closed-ended questions). Qualitative analysis of the results was performed through a context analysis technique. Setting: the largest public university hospital in Brazil. Participants: 48 women in their third trimester of pregnancy. Findings: most women expressed a preference for vaginal birth, as they perceived that they would have a faster recovery. Women who expressed a preference for caesarean section did so because of lack of pain during the birth and the need for tubal sterilisation. The majority of women considered it important to have experience with a mode of birth in order to choose a preference. Complications associated with maternal illness were very influential in the decision-making process. Key conclusions: these results provide a useful first step towards the identification of aspects of women`s feelings about modes of birth. Most women expressed a preference for vaginal birth. Further exploration of women`s feelings regarding parturition and the decision-making process is required. (C) 2008 Elsevier Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Context: The purpose of this article is to review the history of robotic surgery, its impact on teaching as well as a description of historical and current robots used in the medical arena. Summary of evidence: Although the history of robots dates back to 2000 years or more, the last two decades have seen an outstanding revolution in medicine, due to all the changes that robotic surgery has made in the way of performing, teaching and practicing surgery. Conclusions: Robotic surgery has evolved into a complete and self-contained field, with enormous potential for future development. The results to date have shown that this technology is capable of providing good outcomes and quality care for patients. (C) 2011 AEU. Published by Elsevier Espana, S.L. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to evaluate the efficacy of a cost-effective intra-oral appliance for obstructive sleep apnea syndrome built into a large teaching hospital. Out of 20 evaluated and treated patients, 14 concluded the study: eight men and six women, with a mean age of 42-46 (mean + SD) years and mean body mass index of 27.66. Inclusion criteria were mild or moderate apnea-hypopnea index (AHI) according to a polysomnographic study. All patients were treated with the monobloco intra-oral appliance. They were then submitted to a follow-up polysomnographic study after 60 days using the appliance. An orofacial clinical evaluation was carried out with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) questionnaire and with clinical evaluation questionnaire devised by the Orofacial Pain Team before and 60 days after fitting the intra-oral appliance. The AHI showed a statistically meaningful (p = 0.002) reduction from 15.53 to 7.82 events per hour, a non-statistically significant oxygen saturation increase from 83.36 to 84.86 (p = 0.09), and Epworth`s sleepiness scale reduction from 9.14 to 6.36 (p = 0.001). Three patients did not show any improvement. The most common side effect during the use of the appliance/device was pain and facial discomfort (28.57%), without myofascial or temporomandibular joint pain as evaluated by the RDC/TMD questionnaire. The intra-oral device produced a significant reduction of the apnea-hypopnea index during the study period with the use of the monobloco intra-oral appliance. Patients did not show prior myofascial pain or 60 days after use of the intra-oral appliance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The civil-military dictatorship, which took power in 1964, influenced the daily activities of schools and teachers. Many transformations occurred during this period, including the new legislation enacted under Law 5692/71 and changes which occurred due to the vigilance which teachers felt when working. The memories analyzed here of teachers from public schools in Sao Paulo show different perceptions of this surveillance, involving various forms of acceptance or resistance. The purpose of this article is to show that although there was no direct repression of schools, unlike in the universities, teachers at the elementary school also felt constrained and this can be seen in their educational practices and teaching concepts.