Limonoids showing selective toxicity to DNA repair-deficient yeast and other constituents of Trichilia emetica

Bioactivity-directed fractionation of the MeCOEt extract of Trichilia emetica (Meliaceae) resulted in the isolation of the limonoids nymania 1 (1), drageana 4 (3), trichilin A (4), rohituka 3 (5),and Tr-B (7) and the novel seco-A protolimonoid 8. of these, nymania 1 and Tr-B showed selective inhibitory activity toward DNA repair-deficient yeast mutants. The isolation, structure elucidation, C-13 NMR spectral assignments, and biological activities of:these compounds are reported.

Niobium to alcohol mol ratio control of the concurring esterification and etherification reactions promoted by NbCl5 and Al2O3 catalysts under microwave irradiation

Alcohols and acids can be switched to produce ethers or esters by varying the alcohol to catalyst mol ratio, in a new etherification and esterification method using NbCl5/Al2O3 catalyst under "solvent free" conditions and promoted by MW (microwave) irradiation. A "two sites" mechanism for the reaction is proposed, in an attempt to clarify the tendency of the catalyst to be dependent on the alcohol alone during the esterification process. (c) 2008 Elsevier B.V. All rights reserved.

Risk factors that may signify a propensity to the use of drugs in students at a public university

Introduction: We sought to evaluate the risk factors that may increase the propensity to use licit and illicit drugs among students at a public university. Methods: The project involved students (n = 268) enrolled in the first and fourth years of courses in the areas of the social and biological sciences at a public university. Data collection was conducted by means of self-administered, semistructured questionnaires, based on such standardized assessment instruments as Audit, Assist, Cage and Duse. Collected data were analyzed quantitatively by calculating the percentages and evaluating the data in terms of categories of risk, classifying them by age, gender, religion, schooling, use (before or after entering university) and contexts of use. By means of this survey the researchers were able to correlate the use of drugs to the risk factors that might increase the students’ propensity to use these substances. Results: The results revealed a high proportion of current drug-using students, but showed no significant differences between the first and fourth year students as regards contexts of use. However, 67% of students regarded the university environment as encouraging the use of drugs. Students pointed to such major risk factors as friends’ and fellow-students’ influence, university parties, excessive curiosity and desire to experiment. Conclusion: Due to the high rate of drug use among university students, by the determination of the risk factors related to the university environment and also knowing that the process of addiction is one of growing chemical dependence, the importance of the development and implementation of public health policies at all levels, especially in terms of approaches and specific interventions addressing this population, should be noted.

Effects of an isostretching training protocol to increase the musculoarticular flexibility and other physiological aspetcs on the quality of life

Purpose: To apply the technique of Isostretching in a group of people over age 50 years and compare the flexibility of the posterior muscular chain before and after treatment, observing whether there was improvement in quality of life after the end of the sessions. Method: Eleven healthy and sedentary people from 51 to 74 years old participated in the study, which was conducted in Brazil. To evaluate the flexibility we applied the SF-36 questionnaire and test flexion of the spine before and after the study. Eight domains were accessed with the scores ranging form zero to one hundred. Results And Discussion:The technique was effective to gain flexibility of the posterior muscle group, which results in better quality of life for the participants. The results show that the domains related to physical health obtained the highest scores (“functional capacity”, “limitation in physical aspects” and “pain”). These aspects are strongly emphasised in a physical therapy treatment.