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Biomedical subjects

C R Rodrigues

Publications and source records attributed to C R Rodrigues.

At least 19 recordsLinked to original sources
PubMed2006

HIV-1 reverse transcriptase: a therapeutical target in the spotlight.

Human Immunodeficiency Virus type 1 Reverse Transcriptase (HIV-1 RT) is one of the most important targets for treatment of Acquired Immune Deficiency Syndrome (AIDS). It catalyzes the reverse transcription of HIV-RNA into a double stranded DNA, and the knowledge of its substrate specificity and catalytic mechanism has guided the development of several inhibitors widely used on current HIV/AIDS therapy. However, mutations in HIV-1 RT structure can lead to the emergence of drug-resistant virus strains. The goal of this review is to summarize relevant structural features of HIV-1 RT and its inhibitors in such a way that this cost-effective target in the development of new antiretroviral drugs is particularly highlighted.

Drug Resistance, Viral↗
PubMed2004

Snake venom thrombin-like enzymes: from reptilase to now.

The snake venom thrombin-like enzymes (SVTLEs) comprise a number of serine proteases functionally and structurally related to thrombin. Until recently, only nine complete sequences of this subgroup of the serine protease family were known. Over the past 5 years, the primary structure of several SVTLEs has been characterized, and now this family includes several members. Of particular interest is their possible use in pathologies such as thrombosis. The aim of the present review is to summarize the state of the art concerning the evolutionary, structural and biological features of the SVTLEs.

Amino Acid Sequence↗
PubMed2002

Selective PGHS-2 inhibitors: a rational approach for treatment of the inflammation.

Prostaglandin-H synthase exists in two isoforms, PGHS-1 and PGHS-2. PGHS-1 is present and is constitutively expressed in most cells and tissues, whereas PGHS-2 is mainly thought to mediate inflammation. Selective prostaglandin-H synthase-2 (or cyclooxygenase-2) inhibitors have been shown to be potent antiinflammatory agents with fewer side effects than currently marketed nonsteroidal antiinflammatory drugs (NSAIDs). This review addresses the main classes of the selective PGHS-2 inhibitors whose selectivity is documented by supporting PGHS-1 and PGHS-2 enzyme data. In addition, we also describe our experience in design, synthesis and pharmacological in vivo evaluation of new 1,2-benzodioxole derivatives as candidate of the selective PGHS-2 inhibitors, with special attention to molecular dynamics simulations of these derivatives attached to the active site of PGHS-2.

Animals↗
PubMed2001

Microleakage in primary teeth restored by conventional or bonded amalgam technique.

The aim of this in vitro study was to evaluate marginal leakage in class V restorations in primary teeth restored with amalgam, using three different techniques. Thirty maxillary anterior primary teeth, clinically sound and naturally exfoliated, were used. In group 1 (n = 10), two thin layers of a copal varnish (Cavitine) were applied. In group 2 (n = 10), Scotchbond Multi-Purpose Plus, a dual adhesive system, was used according to manufacturer instructions. In group 3 (n = 10), One-Step adhesive system in combination with a low-viscosity resin (Resinomer) were used according to manufacturer instructions. All samples were restored with a high-copper dental amalgam alloy (GS 80, SDI). After restoration, the samples were stored in normal saline at 37 degrees C for 72 h. The specimens were polished, thermocycled (500 cycles, 5 degrees and 55 degrees C, 30-s dwell time) and impermeabilized with fingernail polish to within 1.0 mm of the restoration margins. The teeth were then placed in 0.5% methylene blue for 4 h. Finally, the samples were sectioned and evaluated for marginal leakage. The Kruskal-Wallis test showed that the filled adhesive resin (group 3) had the least microleakage. There was no significant difference between groups 1 and 2.

Composite Resins↗
PubMed2000

Chiral gas chromatographic separation of 2-oxabicyclo[3.3.0]octane derivatives and their synthetic precursors.

Chiral GC separation of (+/-)-2-allyl-2-carboethoxycyclopentanone (9) and the alcohols (+/-)-3-(hydroxymethyl)-5-carboethoxy-2-oxabicyclo[3.3.0]octane (7), (+/-)-2-allyl-2-carboethoxycyclopentanol (8), and their acetylated and trifluoroacetylated derivatives were investigated on three derivatized beta-cyclodextrins (CDs) diluted in SE-54 or 1701-OH: 2,3,6-tri-O-methyl-beta-CD (PMCD); 2,3-di-O-methyl-6-O-(tert-butyldimethylsilyl)-beta-CD (DIMETBCD); 2,3-di-O-acetyl-6-O-(tert-butyldimethylsilyl)-beta-CD (DIACTBCD). The understanding of these chiral separations is extremely relevant, since cyclopentanic and bicyclic cyclopentanic rings are common structural features of many important natural products and new pharmaceutical drugs. In general DIMETBCD diluted in SE-54 showed the best chiral resolution to alcohols 7 and 8 and only DIACTBCD showed enantioselectivity to 9. Hydrogen bonds prediction and dipole moments data were obtained by molecular modeling calculations for 7ab and 8ab and Ac and TFA derivatives. Comparison of these data with the chromatographic parameters for the related compounds were used to explain the differences of their elution orders and diastereo- and enantiomeric separations on the above chiral stationary phases (CSPs). The results suggest that the CSPs enantioselectivities are not affected by the carboethoxy-functionalized cyclopentanic and bicyclic cyclopentanic rings themselves but mainly by the functional group on the other stereogenic center.

Bridged Bicyclo Compounds, Heterocyclic↗
PubMed2000

Synthesis and pharmacological evaluation of novel heterotricyclic acylhydrazone derivatives, designed as PAF antagonists.

This paper describes the synthesis and the antiplatelet properties of new heterotricyclic N-acylhydrazone derivatives (7a-e), structurally analogous to known hetrazepinic PAF antagonists, exploring molecular hybridization as a tool for molecular designing. The synthetic route employed to access compounds (7a-e) used, as starting material, the previously described methyl 3-hydroxy-8-methyl-6-phenyl-6H-pyrazolo[3,4-b]thieno[2, 3-d]pyridine-2-carboxylate derivative. The results from inhibitory effects of these novel acylhydrazone derivatives (7a-e) upon PAF-induced platelet aggregation, indicated that all compounds present a significant antithrombotic profile.

Animals↗
PubMed2000

Design and synthesis of novel potent antinociceptive agents: methyl-imidazolyl N-acylhydrazone derivatives.

This paper describes recent results of design, synthesis and pharmacological evaluation of new N-heterocyclic functionalized N-acylhydrazone compounds, belonging to the 2-methyl-imidazolyl-3-acylhydrazone class (4a-e). These compounds were planned by applying the molecular simplification strategy to propose the structural modifications on the previously described functionalized imidazo [1,2-a]pyridine 3-acylhydrazone series (2), which presented an important analgesic profile. This new series (4) was synthesized in order to investigate the possible pharmacophoric contribution of the N-heteroaromatic ring and N-acylhydrazone moieties to the analgesic activity. Compounds 4a-b are the most potent antinociceptive agents from this series.

Acetic Acid↗
PubMed1999

Proposal of a new PAF pharmacophoric map by the AM1 method.

PAF is a powerful phospholipid-derived autacoid involved in many pathophysiological processes. Many PAF antagonists have been synthesized and assayed for therapeutic purposes. We have synthesized derivatives (5-7), structurally related to WEB 2086 (1), which were rationally designed based on a planar PAF receptor model previously described by Bures et al. (1994; J. Chem. Inf. Comput. Sci. 24, 218-223). However, pharmacological studies revealed that derivatives (5-7) were inactive as PAF antagonists. AM1 quantum calculations of classical PAF antagonists (1-4), as well as of our derivatives (5-7), demonstrated that electronic features alone are unable to explain the lack of the activity of (5-7). These results induced us to propose a new tridimensional PAF receptor pharmacophoric map by analyzing all stable conformations obtained for derivatives (1-4). The interpoint distances (D1-D5) revealed that the lowest-energy conformers of (5-7) had similar geometries to derivatives (1-4). So, these aspects could not explain the inactivity of the compounds (6-7). The proposed model suggests that the best fit of antagonist compounds may involve the participation of a sulfur atom electron lone pair adequately oriented in relation to the plane of a N-aromatic ring present in the compounds investigated.

Azepines↗
PubMed1996

[The importance of the pediatrician in oral health care promotion].

The degree to which the pediatrician's knowledge might contribute to preventive dentistry is investigated. Questionnaires concerning aspects such as breastfeeding, diet, pacifier use, fluoride use, oral hygiene and the recommended moment for the first dental visit were sent to a random sample of 85 pediatricians in S. José dos Campos. Answers were received from 48 (56.4%) of them. Data showed that orientation about preventive dentistry was not a common procedure among the majority of the pediatricians, suggesting that better integration between physician and dentist is necessary if children are to grow up with better general and dental health.

Age Factors↗
PubMed1996

Reliability of the Portuguese version of the structured clinical interview for DSM-III-R (SCID) in a Brazilian sample of psychiatric outpatients.

The objective of the present study was to determine the reliability of psychiatric diagnoses using a translation and adaptation of Portuguese of the "Structured Clinical Interview for DSM-III-R-patient version" (SCID-P) and the "Structured Clinical Interview for DSM-III-R Personality Disorders" (SCID-II), using the joint interviews methodology. Thirty-nine subjects were evaluated using the SCID-P and 20 of them using the SCID-II. Interrater reliability was analyzed statistically by means of the Kappa Coefficient. Agreement between results obtained with SCID-P was statistically significant for the major diagnostic categories of DSM-III-R and for 10 of the 12 specific diagnostic categories studied (a minimum of 4 subjects per diagnosis). Agreement was not statistically significant for Psychotic Disorder Not Otherwise Specified (NOS) and for Other Bipolar Disorder. The Weighted Kappa for the main diagnoses and the Overall Kappa for the entire set of 25 specific diagnostic categories proposed by the SCID-P were statistically significant. The general agreement for Personality Disorders with SCID-II was statistically significant. The Kappa Coefficient was determined for the Avoidant, Paranoid, Histrionic and Borderline Personality Disorders and for the Conduct Disorder. The remaining Personality Disorders were not analyzed statistically because of their low prevalence in the sample. Agreement was not significant only for the Histrionic Personality Disorder. These data suggest that the translation and adaptation of the SCID-P and SCID-II to Portuguese presents, in general, good reliability indices, and thus its use is recommended.

Adult↗
PubMed1995

Reliability, validity and factorial dimensions of the Interactive Observation Scale for Psychiatric Inpatients.

The Interactive Observation Scale for Psychiatric Inpatients (IOSPI) is characterized by the necessity of interaction between the rater and the patient during the evaluation process. The reliability, validity and factor structure of the IOSPI were evaluated by using a total of 186 sets of ratings accomplished by 2 nursing aides on 34 adult psychiatric inpatients submitted to weekly evaluations during the 3 first weeks of hospitalization. The patients were observed by the 2 nursing aides simultaneously during the morning shift (5 h). In the afternoon of the same day, they were interviewed by two psychiatrists who filled in separately the Brief Psychiatric Rating Scale (BPRS). Factor analysis of the 16 IOSPI items revealed 5 distinct clusters of items, which represented higher-order constructs of social interest, psychomotor agitation, psychoticism, neatness and irritability. It was found that the IOSPI has significant interrater reliability, estimated by an intraclass correlation coefficient of total score and factor score. The total scores of the IOSPI showed a significant correlation with the total scores of the BPRS, meeting the criteria of concurrent validity. The criteria of predictive validity were also met, since the patients who could be discharged presented IOSPI scores significantly lower than the patients who could not be discharged. In conclusion, the IOSPI met the requirements of an evaluation scale and can stimulate therapeutic attitudes of the nursing staff by its characteristics of interactive observation.

Factor Analysis, Statistical↗
PubMed1980

[Proposal of a model for the evaluation of priorities in drawing up the medical curriculum in the area of medical psychology and psychiatry].

The author describes the methods used in designing a questionnaire for studying curricular priorities in the areas of medical psychology and psychiatry by taking a survey of opinions and suggestions among the medical profession. A private study was done and a draft questionnaire tested with the cooperation of 40 faculty members of two public medical schools in São Paulo state. It is suggested that this methodology could be used for similar purposes in other areas of medical education.

Brazil↗
PubMedDate not supplied

[Prevalence of iron deficiency anemia and risk indicators in children from 12 to 18 months attended at the outpatient clinic of Instituto de Puericultura e Pediatria Martagão Gesteira].

OBJECTIVES: The prevalence of iron deficiency anemia and the associated risk indicators were studied in children from 12 to 18 months at the outpatient unit of IPPMG, in order to evaluate and monitor the service. METHODS: This is a cross-sectional descriptive study of 288 children seen at the outpatient unit of IPPMG, from January to December 1993. Anemia was diagnosed by dosage of seric hemoglobin. The studied risk indicators were: prenatal care, birth weight, pediatric follow-up, socio-economic aspects, breast-feeding pattern, nutritional status, and iron prescription. Data were computerized and analyzed by EPIINFO and EGRET softwares. Statistical analysis was performed by Pearson chi(2), and breast-feeding pattern was analyzed by the Kaplan-Meier survival curves. RESULTS: Fifty percent of all children had anemia and 13.2% had severe anemia. Children had an early entry to follow-up at the clinic, and the number of consultations was adequate, according to the recommendations of the Ministry of Health. Only 27% of families had a "per capita" income above one minimum salary, although most had adequate housing and environmental conditions. The median duration of breast-feeding was 7.8 and of exclusive breast-feeding was 3.2 months. No association between anemia and income, early weaning, low-birth weight or undernutrition was found. CONCLUSION: The prevalence of anemia was extremely high, indicating the need for a specific monitoring system for the occurrence of iron deficiency anemia in this service.

English Abstract↗
PubMedDate not supplied

The pedagogic training of graduate students at the Faculty of Medicine of Ribeirão Preto.

In a discussion of the objectives of the Post-Graduate Course of the Faculty of Medicine of Ribeirão Preto, i.e., the training of future medical educators as teachers, the author describes the major effort of the School to achieve this objective during the last twenty years. Special emphasis is placed on the disciplines "Pedagogy in the Biomedical Area-Seminars I and II" which have presented persistent administrative difficulties. The author comments about the attitudes that seem to prevail in Brazilian Universities, which attribute a very high value to scientific productivity at the expense of teaching, and therefore represent an obstacle to achieving the objective in question. Some procedures that may result in changes in attitude towards medical education, with an improvement in the area, are also discussed.

Brazil↗
PubMedDate not supplied

[Simplified oral hygiene index for ages 4 to 6 and 7 to 10 (deciduous and mixed dentition)].

The purpose of this research is to obtain simplified index to evaluate oral hygiene in children. They are divided in two groups: 1) 4-6 years and; 2) 7-10 years. The criteria described by GREEN & VERMILLION, 1960 and 1964 were selected. Calculus was excluded. Once obtained the total data, a simplified of the total index was performed. For the ages 4 to 6 years, we selected labial surfaces of the 54, 61, 82 and the lingual surface of 75. For the mixed dentition we added the labial surface of 26 and the lingual surface of 46. In both dentition, simplified index showed significant correlation with the total index.

Child↗
PubMedDate not supplied

[Simplified gingival index for ages 4 to 6 and 7 to 10. (Deciduous and mixed dentition)].

The main purpose of this research is to obtain an simplified gingival index. Four hundred and twenty children, both sexes 4 to 10 years of age were selected. They are divided in two groups: 4-6 years and 7-10 years. For gingival index, the criteria based on SCHOUR & MASSLER, 1947, were used. To obtain the total data of the studied conditions, a simplification of the total index was performed. For the ages 4 to 6 years, we selected labial surfaces of the 54, 61, 75, 82. For the ages 7 to 10 years, we added the labial surfaces of 26 and 46. The means for the total and simplified index were obtained for each age group sex. The data were analysed by Pearson's correlation coefficient and linear regression. In both dentitions, the simplified index showed significant correlation with the total index.

Child↗