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C Rodríguez

Publications and source records attributed to C Rodríguez.

At least 145 records · Page 8Linked to original sources
PubMed1996

Trends in obesity differences by educational level in Spain.

Our objective was to study the trend in differences in the frequency of obesity by educational level in the general population 20 to 64 years of age. We used data from two cross-sectional health surveys carried out in 1987 and 1993 in representative samples of the Spanish population. We investigated the relation between obesity and educational level during the periods 1987 and 1993, taking into account the main factors confounding the relation. We used, as setting, the National Health Interview Surveys representative of the whole Spanish population. In both men and women, the highest odds ratios (ORs) for obesity were observed at lower educational levels. These differences increased in women between 1987 and 1993, while they decreased in men during the same period. Evidence of increased educational differences in the frequency of obesity indicates that future studies should focus on the evaluation and monitoring of this trend in the population.

Adult↗
PubMed1996

The evolutionary history of Drosophila buzzatii. XXXIII. Are Opuntia hosts a selective factor for the inversion polymorphism?

Previous work has shown fitness differences among chromosomal arrangements by means of selection component analysis in two Drosophila buzzatii natural populations, one of which is native to Argentina and the other a colonized population from Carboneras, Spain. Founder effects or niche shifts were proposed to explain the differences observed in the pattern of pleiotropic effects of inversions on fitness components. In this paper, we address the possible role of niche shifts by determining whether differential attraction to, oviposition on, or utilization of the rotting cladodes of two different Opuntia species (O. quimilo and O. ficus-indica) occurred among individuals carrying different second chromosome karyotypes in a natural Argentinian population. Through the analysis of more than 2500 individuals comprising five different life cycle stages associated with the necroses of these two cactus species, we found that the distributions of inversion frequencies in samples of adult flies, third instar larvae and emerging adults collected on both Opuntia species were not significantly different. Likewise, no evidence of differential oviposition was observed. These findings suggest that niche shifts cannot, solely, account for the changes observed in the Carboneras population. In addition, the selection component analysis did not reveal any significant relationship between chromosomal arrangements and the fitness components tested. These results suggest either that fitness differences might be too small to be detected or that the assumptions of the model concerning the mode of selection may not be tenable in the studied population.

Animals↗
PubMed1996

Neurohormone melatonin prevents cell damage: effect on gene expression for antioxidant enzymes.

It is well known that porphyrins cause a toxic light-mediated effect due to their capability to generate free radicals. Several reports have proved that melatonin is a potent free radical scavenger. The aim of this work has been to study the ability of melatonin to prevent the cell damage caused by porphyrins in the Harderian gland of female Syrian hamsters. Cell injury was evaluated estimating the percentage of damaged cells found in the gland and analyzing the degree of this damage at ultrastructural level. To explain the mechanism by which this hormone could prevent the cell damage caused by porphyrins, its capability to both decrease porphyrin synthesis and increase the mRNA levels for antioxidant enzymes was evaluated. Our results demonstrate that melatonin administration decreases the percentage of damaged cells, porphyrin synthesis, and aminolevulinate synthase (ALA-S) mRNA levels and increases the mRNA levels for manganese superoxide-dismutase and copper-zinc superoxide dismutase. When observed under an electron microscope, the lesions in the clear cells of the treated females were much less severe than in the corresponding cells of the control animals. Melatonin exerts a cytoprotective effect by inhibiting the ALA-S gene expression (and so porphyrin synthesis) and by raising the mRNA levels for several antioxidant enzymes.

5-Aminolevulinate Synthetase↗
PubMed1996

Influence of closure of the reticular groove on the bioavailability and disposition kinetics of meclofenamate in sheep.

Sodium meclofenamate is a non-steroidal anti-inflammatory drug with anaphylactic protective activity in cattle. The objectives of this study were to describe the pharmacokinetic behaviour of sodium meclofenamate after intravenous and oral administration to sheep and to determine the influence of closure of the reticular groove on the bioavailability of the drug. Sodium meclofenamate was administered by the intravenous (2.2 mg/kg) and oral (20 mg/kg) routes to sheep (n = 6). During the oral study the reticular groove was closed by intravenous administration of lysine vasopressin (0.3 IU/kg) or left open (saline solution). The closure of the reticular groove was assessed by determination of the blood glucose curves after oral administration of a glucose solution. After intravenous administration of meclofenamate, the distribution and elimination half-lives of the drug were 7.2 min and 542 min respectively, Vss was 1.68 L/kg and ClB was 2.47 mliter/min kg. Two different patterns of the plasma concentration curves were observed after oral administration of sodium meclofenamate. When the reticular groove was closed, two peaks were observed (tmax-1 12-15 min, Cmax-1 3.30-24.01 micrograms/mliter; and tmax-2' 52.50-75 min, Cmax-2, 6.45-11.08 micrograms/mliter).

Administration, Oral↗
PubMed1996

Evidence that Shh cooperates with a retinoic acid inducible co-factor to establish ZPA-like activity.

Patterning across the anteroposterior axis of the vertebrate limb bud involves a signal from the polarizing region, a small group of cells at the posterior margin of the bud. Retinoic acid (RA; Tickle, C., Alberts, B., Wolpert, L. and Lee, J. (1982) Nature 296, 554-566) and Sonic hedgehog (Shh; Riddle, R. D. Johnson, R. L., Laufer, E. and Tabin, C. J. (1993) Cell 25, 1401-1416; Chang, D. T., Lopez, A., von Kessler, D. P., Chiang, C., Simandl, B. K., Zhao, R., Seldin, M. F., Fallon, J. F. and Beachy, P. A. (1994 Development 120, 3339-3353) have been independently postulated as such signals because they can mimic the mirror image digit duplication obtained after grafting polarizing cells to the anterior of limb buds. Here we show that a embryonal carcinoma cell line, P19, transfected with a Shh expression vector shows low polarizing activity, but when cultured with retinoic acid, duplications like those induced by the polarizing region (ZPA) arise. Complete duplications are also obtained by cotransfecting P19 Shh cells with a constitutively active human retinoic acid receptor (VP16-hRARalpha). These data suggest that Shh and RA cooperate in generating ZPA activity and that Shh, while essential, may not act alone in this process.

Animals↗
PubMed1996

[PSA levels and its relationship with digital examination, age, and score of prostatic symptoms].

Between November 1992 and March 1993 our Service conducted a campaign for early detection of prostate disease among the male population of Vigo. The study focused in the relationship of PSA with the age, rectal examination and prostate symptomatology score. In view of the results obtained it has been concluded that PSA levels increase gradually as a function of age, volume and prostate symptomatology score.

Age Distribution↗
PubMed1996

[Unexplained remission of common variable immunodeficiency: analysis of a clinical case].

We report a 26 years old female with a common variable immunodeficiency diagnosed at the age of 21, with recurrent pulmonary and sinusal bacterial infections, that had a clinical and laboratory remission. At the moment of diagnosis, she had agammaglobulinemia in the protein electrophoresis, very low level of IgG and IgM and absence of IgA. Absolute counts of CD4(+) T lymphocytes were low and CD8(+) were normal. B lymphocyte count was normal. Five years later, a repeated study revealed normal levels of all these parameters, excepting IgA that continued to be undetectable. We propose that the remission could be due to a decrease in suppressor activity of T lymphocytes. There is no documented evidence of infectious factors or the use of immunological therapy that could have influenced the course of the disease.

Adult↗
PubMed1996

[Persistence of the cognitive effects of early stimulation assessed with an animal model].

Human and animal studies have clearly demonstrated the advantageous effects of sensorially enriched rearing environments. Nevertheless, little work has been done concerning the long-lasting persistence of all these behavioral modifications. To undertake this question, a very early enrichment animal model was used. From days 10 to 24 after birth, 28 male albino rats were exposed to a multisensory stimulated environment, while other 28 littermates constituted the control group. At 3 and 6 months old two cognitive abilities were analyzed; the spatial working memory (short term memory) and the latent learning capacity (long term memory). The results evidenced an improved working memory in both 3 and 6 months old rats exposed to the early enriched environment. Moreover, the adult early stimulated group performed as well as younger subjects both on error scores and speed to solve this test. Only in the adult group of rats a superior latent learning capacity of stimulated subjects was evidenced. To conclude, the early enriched environment induced: a) persistent cognitive benefits in the adult rat and b) a more relevant influence on the subsequent behavior of older rather than younger subjects.

Age Factors↗
PubMed1995

[Carotid atherosclerosis evaluated by two-dimensional ultrasonography in patients with primary hypercholesterolemia].

BACKGROUND: Two-dimension ultrasonography permits to noninvasively quantify extracoronary atherosclerosis. The objective of this study was to assess preclinical atherosclerosis of the extracranial carotid arteries in patients with primary hypercholesterolemia. METHODS: Lipid and nonlipid cardiovascular risk factors were evaluated in 206 patients with dyslipidemia (127 men and 79 women, mean age 49 years, range 18-75), and a multifactorial cardiovascular risk profile was constructed for each patient. Ultrasound measurements of the intima-media thickness in the common carotid artery of each side were taken, and the number and height of any atheroma plaques present were quantified. RESULTS: Asymptomatic plaques were found in 120 patients (58%), and were more frequent in men than in women (65 vs 47%, p = 0.009), and in patients with than in those without prior coronary heart disease (80 vs 50%, p < 0.001). Both intimal thickening, indicative of early atherosclerosis, and the extent of arterial wall involvement with plaques, which represents an advanced stage of the disease, increased significantly with age and with increasing multifactorial cardiovascular risk, reflecting a positive relation between signs of atherosclerosis and the burden of risk factors. Intima-media thickness also increased with increasing plaque score, indicating the generalization of atherosclerosis. CONCLUSIONS: The high prevalence of preclinical carotid atherosclerosis confirms the atherogenic risk of primary dyslipidemias. The relation between carotid lesions and both coronary heart disease and multifactorial risk supports the validity of arterial ultrasound studies for cardiovascular risk prediction.

Adolescent↗
PubMed1995

Determination of epitestosterone and testosterone in urine by high-performance liquid chromatography.

This paper describes an alternative HPLC method for the determination of testosterone and epitestosterone, which is simple, rapid, selective, sensitive and reproducible. Samples were prepared using a previous enzymatic hydrolysis with liquid-liquid extraction. The determination was carried out on a Hypersil BDS-C18 reversed-phase column with gradient elution and UV absorbance detection (240 nm). The limits of quantification (signal-to-noise ratio = 6) were 20 ng/ml for testosterone and 30 ng/ml for epitestosterone.

Chromatography, High Pressure Liquid↗
PubMed1995

Expression of apolipoprotein E in cholesterol-loaded macrophages of extrahepatic tissues during experimental hypercholesterolemia.

To study the expression of extrahepatic apolipoprotein E (apoE) under hypercholesterolemic conditions, apoE mRNA levels were evaluated in 14 tissues of rabbits fed on a cholesterol rich diet and compared to age-matched control animals. In hypercholesterolemic rabbits apoE expression was significantly induced in adipose tissue, adrenals, aorta, lung and spleen. The increase in apoE mRNA levels in lung and spleen was associated with the presence of cholesterol-loaded macrophages. These cells were found to express high levels of apoE mRNA as demonstrated by in situ mRNA hybridization. Our results suggest that extrahepatic tissues would be partially responsible for the rise in serum apoE levels detected under hypercholesterolemic conditions.

Adipose Tissue↗
PubMed1995

Increased socioeconomic differences in mortality in eight Spanish provinces.

In Spain, the study of socioeconomic differences in mortality has been limited by the fact that death certificates often do not include complete information on occupation. In this study, we chose those geographic areas with the highest quality information on occupation of the deceased in order to study socioeconomic differences in mortality from various causes of death. We used information from the death certificates of males who died between 30 and 64 years of age in eight Spanish provinces to compare mortality from the leading causes of death in professionals and managers (group I) and in manual laborers (group II) in 1980-82 and 1988-90. In each period the standardized mortality ratios (SMRs) were higher in group II, except for ischaemic heart disease during the first period, and cancer of the colon and rectum in both, although in the latter case the differences were not statistically significant. The ratio between the SMR from all causes in group II and group I was 1.27 in 1980-82, and 1.72 in 1988-90; for cancer of the colon and rectum the ratio went from 0.98 to 0.84, and for ischaemic heart disease, from 0.80 to 1.31. Except for cancer of the colon and rectum, which resulted in higher mortality in occupational group I, the excess mortality in occupational group II increased between the first and second period. The relation between socioeconomic level and mortality for ischaemic heart disease was reversed, a phenomenon similar to that which took place in the 1960s and 1970s in the developed countries.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Comparison of the effects of nerve growth factor and superoxide dismutase on vascular extravasation in experimental burns.

Superoxide dismutase (SOD), a free-radical scavenger, inhibits the increase of vascular permeability in experimental burn lesions in rats. In this study the aim was to determine whether Nerve Growth Factor (NGF), which has been implicated in the modulation of some inflammatory reactions, behaves in an analogous way. The study compares the haematocrit (Ht) and haemoglobin (Hb) variations in three groups of rats treated respectively with saline solution, SOD and NGF, immediately after causing a 25 per cent dermal burn injury. Statistical comparison (Student's t test) of the Ht and Hb variations between the Control group (Ht and Hb increase) and the NGF group (Ht and Hb decrease), shows significant differences in the intervals between 15 and 60 min (P < 0.01) and between 60 and 120 min (P < 0.05). Although SOD is able to control extravasation in the immediate postburn period (basal-15 min), NGF has a comparable effect in subsequent periods. The overall action of NGF shows that this agent is able to maintain Ht and Hb values at basal levels even after 120 min postburn. These results seem to be the first evidence of an inhibitory effect of NGF on the vascular permeability in burn lesions.

Animals↗
PubMed1995

Different effects of fibrates on the microsomal fatty acid chain elongation and the acyl composition of phospholipids in guinea-pigs.

1. The effects in vitro and in vivo of three fibric acid derivatives, clofibrate (CFB), bezafibrate (BFB) and gemfibrozil (GFB) on some enzyme activities related to fatty acid biosynthesis, namely palmitoyl-CoA synthetase and hydrolases (microsomal and cytosolic), NADH and NADPH cytochrome c reductases and acyl-CoA elongases were investigated in guinea-pigs. 2. The three fibrates inhibited acyl-CoA elongation in vitro, irrespective of the substrate of elongation used (saturated, monounsaturated, polyunsaturated) and with an order of potency GFB > BFB > CFB. In the case of GFB, inhibition occurred at concentrations that can be reached in vivo. 3. Microsomal palmitoyl-CoA hydrolase and synthetase were also inhibited in vitro (GFB > or = BFB > CFB), whereas NADH cytochrome c reductase activity was increased by GFB. Nevertheless, the magnitude of changes were lower than those observed in elongation activities. 4. Treatment with fibrates did not produce peroxisomal proliferation in guinea-pigs, as measured by peroxisomal beta-oxidation activity and liver weight/body weight ratio. Nevertheless, fibrates provoked a reduction in plasma cholesterol and triglycerides, at least in GFB- and BFB-treated animals. 5. Fatty acid elongation was significantly modified by GFB treatment in vivo. The remaining enzyme activities studied were only slightly changed by fibrate treatment. 6. Treatment with BFB and to a lesser extent with CFB, increased the relative proportion of MUFA (palmitoleic and oleic acids) in microsomal phospholipids, whereas PUFA (mainly linoleic acid) decreased. GFB behaved differently, increasing palmitic and linoleic acids and decreasing stearic and oleic acids. The latter changes are attributable to an inhibition of elongation activity by GFB. 7. The changes observed after fibrate treatment in both rats and guinea-pigs, as they are not directly related to peroxisome proliferation, could be more reliably extrapolated to man than those observed only in rats.

Animals↗
PubMed1995

Discrete amplifiable regions (amplicons) in the symbiotic plasmid of Rhizobium etli CFN42.

Frequent tandem amplification of defined regions of the genome, called amplicons, is a common characteristic in the genomes of some Rhizobium species, such as Rhizobium etli. In order to map these zones in a model Rhizobium replicon, we undertook an analysis of the plasticity patterns fostered by amplicons in the pSym (390 kb) of R. etli CFN42. Data presented in this article indicate the presence of four amplicons in pSym, used for the generation of tandem amplifications and deletions. The amplicons are large, ranging from 90 to 175 kb, and they are overlapping. Each amplicon is usually flanked by specific reiterated sequences. Formation of amplifications and deletions requires an active recA gene. All the amplicons detected are concentrated in a zone of roughly one-third of pSym, covering most of the symbiotic genes detected in this plasmid. No amplicons were detected in the remaining two-thirds of pSym. These data support the idea that most of the known symbiotic genes in this plasmid are located in a genomic region that is prone to the formation of frequent tandem amplification.

Crossing Over, Genetic↗
PubMed1995

Low birth weight in Spain associated with sociodemographic factors.

STUDY OBJECTIVE: To describe the effect of different social and demographic characteristics on low birth weight (LBW) (less than 2500 g) in Spain, in both preterm (less than 37 weeks' gestation) and term infants (between 37 and 42 weeks' gestation). DESIGN: The study used data obtained from the Spanish birth registry. SETTING: The study was based on those live born infants registered in 1988 from provinces where the birthweight details were completed in at least 99.5% of the birth registration records. PARTICIPANTS: A total of 1332 preterm LBW infants, 1292 term LBW infants, and 38,967 controls were included in the study. MEASUREMENTS AND MAIN RESULTS: The odds ratio (OR) calculated by logistic regression was used as the measure of association between LBW and the sociodemographic variables. The highest ORs of preterm LBW were found in mothers younger than 20 years (1.32; 95% CI 0.98, 1.77) and older than 34 years (1.28; 95% CI 1.04, 1.59), in unmarried mothers (1.68; 95% CI 1.36, 2.07), and in fathers with manual occupations (1.26; 95% CI 1.08, 1.46). In term, live born infants the highest ORs were found in adolescent mothers (1.63; 95% CI 1.25, 2.14), in first born live born infants (1.38; 95% CI 1.09, 1.74) or the fourth born or more (1.28; 95% CI 0.91, 1.80), in unmarried mothers (1.55; 95% CI 1.27, 1.90), in housewives (1.13; 95% CI 0.99, 1.29), and in fathers with manual occupations (1.21; 95% CI 1.04, 1.42). CONCLUSIONS: The results have allowed documentation of the risk of preterm and term LBW in various age and social groups in Spain.

Adolescent↗