Calcium channel inhibitors, nitrate derivative. Principles and rules of use

The hypothesis that it is the variability of a person's identity--as opposed to the particular combinations of identities--that produces stress during the acculturation process was examined. Two hundred ninety-five native Anglophone students at the University of Ottawa, Ontario, Canada, provided demographic data and completed the following measures: the Beck Depression Inventory (Beck & Beck, 1972), Rosenberg's Self-Esteem Scale (1965), the Situated Identity Measure (Clément & Noels, 1992), and the Psychological Stress Measure (Lemyre, Tessier, & Fillion, 1990). Results of ANOVAs contrasting level of identification and variability of identification indicated that an exclusively Anglophone identity was related to a higher level of depression, lower self-esteem, and a higher level of stress than the other modes of acculturation, but only when the variability in identity with the English group was high. Thus, the participants who identified strongly with the English group but were not committed to this identity experienced more psychological adjustment problems.     

Correlation between oral drug absorption in humans, and apparent drug permeability in TC-7 cells, a human epithelial intestinal cell line: comparison with the parental Caco-2 cell line

PURPOSE: To determine and compare the relationship between in vivo oral absorption in humans and the apparent permeability coefficients (Papp) obtained in vitro on two human intestinal epithelial cell lines, the parental Caco-2 and the TC-7 clone. METHODS: Both cell lines were grown for 5-35 days on tissue culture-treated inserts. Cell monolayers were analysed for their morphology by transmission electron micrography, and for their integrity with respect to transepithelial electrical resistance, mannitol and PEG-4000 transport, and cyclosporin efflux. Papp were determined for 20 compounds exhibiting large differences in chemical structure, molecular weight, transport mechanisms, and percentage of absorption in humans. RESULTS: The TC-7 clone exhibits morphological characteristics similar to those of the parental Caco-2 cell line, concerning apical brush border, microvilli, tight junctions and polarisation of the cell line. The TC-7 clone however appeared more homogenous in terms of cell size. Both cell lines achieved a similar monolayer integrity towards mannitol and PEG-4000. Monolayer integrity was achieved earlier for the TC-7 clone, mainly due to its shorter doubling time, i.e. 26 versus 30 hours for parental Caco-2 cells. When using cyclosporin A as a P-glycoprotein substrate, active efflux was lower in the TC-7 clone than in the parental Caco-2 cells. The Papp and mechanisms of transport (paracellular or transcellular routes, passive diffusion and active transport) were determined for 20 drugs. A relationship was established between the in vivo oral absorption in humans and Papp values, allowing to determine a threshold value for Papp of 2 10(-6) cm/sec, above for which a 100% oral absorption could be expected in humans. Both correlation curves obtained with the two cell types, were almost completely superimposable. These studies also confirmed that the dipeptide transporter is underexpressed in both cell lines. CONCLUSIONS: On the basis of morphological parameters, biochemical activity and drug transport characteristics, the TC-7 clone appeared to be a valuable alternative to the use of parental Caco-2 cells for drug absorption studies.     

Metal-Oxo Species in P450 Enzymes and Biomimetic Models. Oxo-Hydroxo Tautomerism with Water-Soluble Metalloporphyrins

Oxygenation reactions (hydroxylation, epoxidation, N- or S-oxide formation, etc.) catalyzed by cytochrome P450 enzymes and related biomimetic models involve an electrophilic oxidative species as the active species, namely a high-valent metal-oxo intermediate. Among the different methods to study the oxygenation reactions mediated by high-valent metal-oxo porphyrin complexes, the recent discovery of oxo-hydroxo tautomerism provides a useful tool to investigate the mechanism of O-atom transfer reactions in aqueous media.     

Clinical trials and tribulations: lessons learned from recruiting pregnant ex-smokers for relapse prevention.

The development of smoking cessation and relapse prevention interventions for pregnant and postpartum women is a public health priority. However, researchers have consistently reported substantial difficulty in recruiting this population into clinical trials. The problem is particularly acute for relapse prevention studies, which must recruit women who have already quit smoking because of their pregnancy. Although these individuals are an important target for tobacco control efforts, they represent an extremely small subgroup of the general population. This paper describes multiple recruitment strategies used for a clinical trial of a self-help relapse prevention program for pregnant women. The effectiveness of the strategies and the direct expense per participant recruited are provided. A proactive recruitment strategy (telephoning women whose phone numbers were purchased from a marketing firm) was ultimately much more successful than a variety of reactive strategies (advertisements, press releases, direct mail, Web placement, health care provider outreach). We found few differences between proactively and reactively recruited participants on baseline variables. The primary difference was that the former had smoked fewer cigarettes per day and reported lower nicotine dependence prior to quitting. Strengths and limitations of the recruitment strategies are discussed.     

Further exploration of typical and maximum performance criteria: Definitional issues, prediction, and White-Black differences.

Addresses differences between typical and maximum performance criteria with a threefold purpose. First, the growing recognition that it is important to distinguish between typical and maximum performance criteria is examined. Second, clarification of definitional and measurement issues are addressed. Third, results of an empirical study are offered to contribute to the new knowledge base regarding typical and maximum performance criteria. The study investigates differences in validities of cognitive ability predictor measures against supermarket cashier typical and maximum performance criteria reflecting speed and accuracy. White–Black mean score differences on typical and maximum performance criteria are also examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Solubility Studia of Certain 2.3 Quinolino - Phthalidea

The solubilities of feve derivatives of 2.3 quinolino-phthalides in distilled water and in potassiem chloride solatioas of varying ionic atrength was detarained at 25°. 37°. and 51°C. The solubilities were lower in potassium chloride solutions: the over-all “aslting- out” comfficients were caleulated. for the effects of potaasium chloride using the empirical Setschenow equation logSo/S=KC

The differential beats of aolutions ranged from 2kcal/mole to 7.5 kcal/wole and were determined from the slopers of the semi-logaritimumic plots. of the solubilitiea verus the reciprocal temperaturas. The affect of the functional groups on this water solubilities of these compounds will be dlscussed.     

Kinetics interpretation of NiO electrical conductivity under low oxygen pressures

In a previous work it has been stated that the NiO electrical conductivity changes connected to the oxygen pressure changes may be considered as a transitory phenomenon. A mixed kinetics case controlled by the formation of surface cation vacancies and their diffusion in the bulk is proposed to explain the reaction process. By means of an equivalent electrical circuit in good agreement with the kinetics model it was possible to reproduce the experimental phenomenon.     

Neural Networks for Full-Scale Protein Sequence Classification: Sequence Encoding with Singular Value Decomposition

A neural network classification method has been developed as an alternative approach to the search/organization problem of protein sequence databases. The neural networks used are three-layered, feed-forward, back-propagation networks. The protein sequences are encoded into neural input vectors by a hashing method that counts occurrences ofn-gram words. A new SVD (singular value decomposition) method, which compresses the long and sparsen-gram input vectors and captures semantics ofn-gram words, has improved the generalization capability of the network. A full-scale protein classification system has been implemented on a Cray supercomputer to classify unknown sequences into 3311 PIR (Protein Identification Resource) superfamilies/families at a speed of less than 0.05 CPU second per sequence. The sensitivity is close to 90% overall, and approaches 100% for large superfamilies. The system could be used to reduce the database search time and is being used to help organize the PIR protein sequence database.     

Simulation des performances d'un réfrigérateur solaire à adsorption: 2. Fonctionnement avec stockage de froid dans deux climats différents

The models described in this article simulate the solid-adsorption cycles of a solar refrigerator. They are used for calculating the performances of the refrigerator as a function of the climatic conditions, and thus optimizing its operation and sizing. The results show that for the same season the performances of the refrigerator are different for the climates of Rabat and Marrakesh. The study of the cold storage shows that, although the annual mean cold production is similar for both sites, the distribution of cooling-shortage days is totally different. In contrast with Rabat, where the problem of cold storage is due to sequences of successive days with low incident solar energy, the problem in Marrakesh is due to high values of ambient temperature during quite a long period of the year, which reduce significantly the refrigerator performances.