Biomedical subjects

A Villarroya

Publications and source records attributed to A Villarroya.

5 recordsLinked to original sources

PubMed1995

Discriminant analysis algorithm based on a distance function and on a Bayesian decision.

We propose a new algorithm for the allocation of an individual to one of several possible groups or populations. The algorithm enables us to define a finite partition over the sample space, based on distance function. This partition is used, jointly with the application of a standard Bayesian decision rule, to allocate individuals to the populations. The algorithm also provides a measure of the allocation confidence for each individual, in a similar manner to that of logistic regression. The error rates for classification are also computed using the leave-one-out method. Results are compared with those obtained with other discriminant analysis techniques previously reported: Fisher's linear discriminant function, the quadratic discriminant function, logistic discrimination, and others.

Adolescent↗

PubMed1991

ADH and phylogenetic relationships of Drosophila lebanonesis (Scaptodrosophila).

Increasing data on Drosophila alcohol dehydrogenase (ADH) sequences have made it possible to calculate the rate of amino acid replacement per year, which is 1.7 x 10(-9). This value makes this protein suitable for reconstructing phylogenetic relationships within the genus for those species for which no molecular data are available such as Scaptodrosophila. The amino acid sequence of Drosophila lebanonensis is compared to all of the already known Drosophila ADHs, stressing the unique characteristic features of this protein such as the conservation of an initiating methionine at the N-terminus, the unique replacement of a glycine by an alanine at a very conserved position in the NAD domain of all dehydrogenases, the lack of a slow-migrating peptide, and the total conservation of the maximally hydrophilic peptide. The functional significance of these features is discussed. Although the percent amino acid identity of the ADH molecule in Drosophila decreases as the number of sequences compared increases, the conservation of residue type in terms of size and hydrophobocity for the ADH molecule is shown to be very high throughout the genus Drosophila. The distance matrix and parsimony methods used to establish the phylogenetic relationships of D. lebanonensis show that the three subgenera, Scaptodrosophila, Drosophila, and Sophophora separated at approximately the same time.

Alcohol Dehydrogenase↗

PubMed1991

[Randomized double-blind study of delayed-action verapamil as a single dose versus 2 doses daily in patients with moderate hypertension].

The antihypertensive action of sustained release verapamil is, in the majority of cases, obtained with a dosage of 240 mg per day. In certain patients, it is necessary to increase the daily dose to 360 or even 480 mg. This dosage increase most often leads to twice daily administration. In the present trial (18 patients included), the efficacy 360 mg of sustained release verapamil was compared double-blind with that of 360 mg as two divided doses. The antihypertensive action of sustained release verapamil as a single dose was shown to be identical to that of two daily doses. It is therefore felt to be unnecessary to increase the number of daily doses in parallel with dosage increases. There is absolutely no doubt that single dose monotherapy leads to better compliance.

Delayed-Action Preparations↗

PubMed1989

The primary structure of alcohol dehydrogenase from Drosophila lebanonensis. Extensive variation within insect 'short-chain' alcohol dehydrogenase lacking zinc.

Insect alcohol dehydrogenase is highly different from the well-known yeast and mammalian alcohol dehydrogenases. The enzyme from Drosophila lebanonensis has now been characterized by protein analysis and was found to have a 254-residue protein chain with an acetyl-blocked N-terminal Met. Comparisons with the structures of the enzyme from other species allows judgement of the extent of variability within the insect alcohol dehydrogenases. They have diverged to a considerable extent; two forms analyzed at the protein level differ at 18% of all residues, and all the known Drosophila alcohol dehydrogenase structures reveal differences at 72 positions. Some deviations, against a background similarity, in the extent of changes are noted among the parts corresponding to different exons. The structural variation within Drosophila is about as large as the one for the mammalian zinc-containing alcohol dehydrogenase. Consequently, the results illustrate Drosophila relationships and establish great variations also for group of alcohol dehydrogenases lacking zinc.

Alcohol Dehydrogenase↗

PubMedDate not supplied

[Effects of exercise in the elderly with chronic renal failure].

The population studied in this paper is composed of 10 patients under hemodialysis, who have underwent a general exploration, a stress test, a spirometry, an analytic control and assessment of exercise their psychological situation, before and after the programme. At the end of the training programme there is an important increase in the SVC and the FVC, as well as the power and time of the stress test. The psychological state improves as well as the anaemia.

Aged↗