Biomedical subjects

R García-García

Publications and source records attributed to R García-García.

4 recordsLinked to original sources

PubMed2003

New model for the hydroxyapatite-octacalcium phosphate interface.

Some experimental results have indicated that hydroxyapatite (HA) and octacalcium phosphate (OCP) can form an epitaxic interface. Subsequently the OCP-HA interface has become of great biological interest in the context of mineralized tissue formation. In this work a new OCP-HA interface model based on Brown's proposed configuration [Brown (1962), Nature, 197, 1048-1050] and using the minimum interface free-energy optimization is presented. This new model is formed by half a unit cell of HA and one unit cell of OCP, as in Brown's model, but in our case [1-210] of HA is 'glued' with [010] of OCP. Therefore, the relationship found was: [000-1](HA) parallel to [001](OCP) and [1-210](HA) parallel to [010](OCP). Self-consistent field methods were used for the analysis of Brown's model and ours. It is shown that the atoms in our model have similar environments as in the HA and OCP unit cells and that, as a result of the differences between HA and OCP unit-cell parameters, this interface presents misfit-dislocation-like features. High-resolution transmission electron microscopy (HREM) simulated images for the new interface model have been included and, when they are compared with the experimental ones, the similarity is quite good.

Journal Article↗

PubMed2001

Procedure for successful interspecific embryo transfer from mouflon (Ovis gmelini musimon) to Spanish Merino sheep (Ovis aries).

Embryos from five anesthetized mouflons (Ovis gmelini musimon), superovulated with FSH-o (Ovagen) were transferred into preselected Spanish Merino sheep (Ovis aries). Myorelaxation was complete in four of five donor mouflons. The status of the uterus of potential recipients was evaluated by transrectal ultrasonography, and those ewes with fluid in the uterine horn were rejected. The corpus luteum in each ewe was assessed ultrasonographically the day before surgery. Plasma progesterone levels and the quality of the corpora lutea were the criteria for selection of recipients. Ten embryos were transferred to the five selected Spanish Merino recipients, resulting in four pregnancies and seven live-born lambs, including three sets of twins. This study shows that determination of plasma progesterone levels combined with ultrasonographic assessment of the corpus luteum provides information useful for screening of potential recipients.

Anesthetics, Dissociative↗

PubMed1996

[The 'clock drawing test' in healthy elderly people].

INTRODUCTION AND OBJECTIVE: In this paper we aim to determine the normal values of the clock drawing test in a sample group of 58 healthy elderly persons as a neuropsychological parameter for the evaluation of certain cognitive functions. MATERIAL AND METHODS: For this we have used our own adaptation of the quantitative parameters of the clock drawing test in the evaluation 'on command' and 'on copying'. We have also evaluated the possible interaction of the test with the following sample parameters: sex, age, and educational level and we have calculated the inter-examiner reliability of the test. RESULTS: The average scores obtained were: 8.04 'on-command' (SD 1.60) and 9.20 (SD 0.93) 'on-copying'. CONCLUSIONS: On analysis of our results we have not observed interaction of the parameters used (age, sex and educational level) with the scores obtained in the test, while there was a high level of inter-examiner reliability.

Aged↗

PubMedDate not supplied

[A proposal for application and scoring of the Clock Drawing Test in Alzheimer's disease].

INTRODUCTION: The Clock Drawing Test (CDT) has been used in recent years as a simple neuropsychological instrument to assess cognitive deterioration associated with dementia, even though uniform operative criteria with respect to its application and scoring have not been established. OBJECTIVE: To present application normatives and establish the most relevant psychometric criteria of the CDT in a sample of healthy subjects (HS) and patients with Alzheimer's disease (AD). PATIENTS AND METHODS: 56 patients were selected of which 35 were female and 21 were male. The patients' mean age was 72.7 with a standard deviation of 7.64. All of whom where probable AD patients according to the NINCDS-ADRDA criteria at stage 1 CDR. The group of HS was made up of 56 control subjects (34 female, 22 male) with a mean age of 72.14 and a standard deviation of 7.2. The CDT was applied in both its command (COM) and copy (COP) experimental conditions. RESULTS: The main psychometric parameters analysed in the studied series showed the following values: internal consistency (Cronbach's alpha coefficient 0.9029); cut off point CT COM 6 with 92.80, sensitivity; false negatives (FN) 7.2 with a specificity rating 93.48; false positive (FP) 6.52 with 93.16 efficacy; cut off point CT COP 8 with 73.11 sensitivity; FN 26.89 with 90.58 specificity; FP 9.42 with 82.49 efficacy. CONCLUSION: The CDT can be used to discriminate between HS and those in the initial stages of AD in the given sample using the established application and scoring criteria.

Aged↗