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J G Rodríguez

Publications and source records attributed to J G Rodríguez.

9 recordsLinked to original sources
PubMed2006

Maximum likelihood mixture estimation to determine metal background values in estuarine and coastal sediments within the European Water Framework Directive.

Some of the recently derived European Directives, such as the Water Framework and Marine Strategy, have, as ultimate aims, to achieve concentrations of hazardous substances in the marine environment near background values. Hence, the determination of natural background levels, in marine sediments, is highly relevant. The present study proposes the use of the maximum likelihood mixture estimation (MLME) to determine regional background levels and upper threshold of metal concentration, with the Basque Country as a case study (with a data set of 575 samples, from estuarine and littoral areas, including both intertidal and subtidal sediments). The heuristic procedure is applied with unimodal data distributions (Cd, Cr, Fe and Ni) and the mixture density estimations, based upon maximum likelihood, are carried out with polypopulational data distributions (As, Cu, Mn, Hg, Pb and Zn). The upper limits of the distribution are proposed, as the limits between 'High Status' and 'Good Status' (according to the Water Framework Directive terminology). The regional upper limits were 0.45 microg g(-1) for Cd, 71 microg g(-1) for Cr, 53,542 microg g(-1) for Fe, 57 microg g(-1) for Ni, 24 microg g(-1) for As, 64 microg g(-1) for Cu, 447 microg g(-1) for Mn, 0.27 microg g(-1) for Hg, 66 microg g(-1) for Pb, and 248 microg g(-1) for Zn. The results from this study can assist further in the determination of sediment reference conditions, to assess chemical status, within the above-mentioned directives; likewise, it will be studied as a useful methodology in determining regional metal backgrounds in other European countries.

Arsenic↗
PubMed1999

Amplification of a 500-base-pair fragment from cultured isolates of Mycobacterium bovis.

The presence of a 500-bp fragment which amplifies a region from the genome of Mycobacterium bovis (J. G. Rodriguez, G. A. Meija, P. Del Portillo, M. E. Patarroyo, and L. A. Murillo, Microbiology 141:2131-2138, 1995) was evaluated by carrying out PCR on 121 M. bovis isolates. The M. bovis strains, previously characterized by culture and biochemical tests, were isolated from cattle in different regions of Argentina, Mexico, and Colombia. Four additional strains isolated from sea lions that belong to the M. tuberculosis complex were also included in the study. All of the isolates tested were PCR positive, rendering the expected 500-bp band and giving a correlation of 100% with previous microbiological characterization. Southern blot analysis revealed a common band of 1, 800 bp and a polymorphic high-molecular-mass hybridization pattern. The results show that this assay may be useful for diagnosis and identification of M. bovis in cattle.

Animals↗
PubMed1994

Cell wall proteins in seedling cotyledons of Prosopis chilensis.

Four cell wall proteins of cotyledons of Prosopis chilensis seedlings were characterized by PAGE and Western analyses using a polyclonal antibody, generated against soybean seed coat extensin. These proteins had M(r)s of 180,000, 126,000, 107,000 and 63,000, as determined by SDS-PAGE. The proteins exhibited a fluorescent positive reaction with dansylhydrazine suggesting that they are glycoproteins; they did not show peroxidase activity. The cell wall proteins were also characterized by their amino acid composition and by their amino-terminal sequence. These analyses revealed that there are two groups of related cell wall proteins in the cotyledons. The first group comprises the proteins of M(r)s 180,000, 126,000, 107,000 which are rich in glutamic acid/glutamine and aspartic acid/asparagine and they have almost identical NH2-terminal sequences. The second group comprises the M(r) 63,000 protein which is rich in proline, glycine, valine and tyrosine, with an NH2-terminal sequence which was very similar to that of soybean proline-rich proteins.

Amino Acid Sequence↗
PubMed1994

[Sulindac and indomethacin effects on lamb fetuses chronically monitored].

Sulindac and indometacin, both prostaglandins inhibitors, have a similar tocolytic effectiveness, in contrast their fetal effects seem to be different. For specify these differences we compared the effects of the infusion of sulindac with known effects of indometacin. We operated 6 fetal lambs, in which polyvinyl catheters were inserted chronically for continuous measure of heart rate, blood pressure, incidence of fetal breathing movements and arterial pH and gas tension. The fetuses were infused in a 2 hour control period with vehicle, and then with 150 mg of either sulindac or indometacin (in alternate days) for a 6 hour period. There was no change in any variable when sulindac was given, but there was a significant increase in fetal breathing movements with indometacin. The reason for this difference is not clear, and requires further studies. These results added to previous reports supports the hypothesis that sulindac could be a first choice tocolytic drug for treatment of premature labor when no fetal effect is desired.

Animals↗
PubMed1994

[Misoprostol--a PGE1 analog for induction of labor at term: comparative and randomized study with oxytocin].

The efficacy of misoprostol (a PGE1 analog) for induction of labor at term was compared with oxytocin by means of an open and randomized study in 153 pregnant women. A vaginal tablet containing 50 mcg of misoprostol was placed intravaginally in 78 women, the remaining 75 patients received i.v. oxytocin (2-32 mU/min). Bishop's score at the entry of the trial was similar in both groups. Delivery within 24 hours was achieved in 85.7% of the patients induced with misoprostol and in 64% of the patients infused with oxytocin (p < 0.05). Mean induction to delivery interval was significantly shorter in the misoprostol group (552 +/- 211 min; mean =SD) in comparison with that of the oxytocin group (745 +/- 292 min; mean +/- SD) (p < 0.05). The probability of still being pregnant at 24 hours (Life table analysis) was 14% (misoprostol group) and 26% (oxitocyn group). The difference was also statistically significant (p < 0.01). No undesirable side effects were observed in any of the patients, however, polisystoly (> 5 contractions in 10 min) was more frequently observed in the patients induced with misoprostol (24.6% vs 13.3%; p = NS). Cesarean section rate was higher in the oxytocin-induced patients (25.3%) than in the misoprostol-induced women (3.8%) (p < 0.05). The main cause of cesarean section was failure to progress in labor in both groups of patients. Neonatal outcome was good in both groups and there were no differences with respect to birthweight or to Apgar scores.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intravaginal↗
PubMed1993

[Hypocalciuria in pre-eclampsia].

Recent studies have associated preeclampsia with hypocalciuria, nevertheless others do not show association. We proposed to determinate if this association exists, so we studied 25 term pregnancies patients (13 normotensives, 7 transient hypertension and 5 preeclamptic). We did not find significative differences in the hematocrit, serum calcium, serum creatinine, platelets count and the 24 hour diuresis between these groups. The serum uric acid was significative lower in the normotensive group (3.5 +/- 0.8 mg/dl) than in the preeclamptic group (4.9 +/- 0.89 mg/dl) (mean +/- SD) (p < 0.05). The 24 hour calciuria was lower in the preeclamptic group (121 +/- 78 mg/24 hours) than in the normotensive (256 +/- 71 mg/24 hours) and transient hypertension group (229 +/- 93 mg/24 hours) (p < 0.05). We measured the creatinine clearance and the fractional excretion of calcium in the transient hypertension and the preeclamptic groups, there was significative difference only in the fractional excretion of calcium (2.5 +/- 0.8% and 1.1 +/- 0.8% respectively) (p < 0.05). All the patients had a good clinical evolution, so the arterial pressure returned to normal values in a mean period within 7 days in both groups. There were 3 newborn who were small for gestational age (1 in the transient hypertension and 2 in the preeclamptic group). The difference we found in the 24 hour calciuria and the fractional excretion of calcium agree with the finds of other authors, further prospective studies are needed to understand the physiology and pathophysiology of calcium metabolism in normal, transient hypertension and preeclamptic pregnancy.

Calcium↗
PubMedDate not supplied

[Enamel resistance to acid dissolution. Its relation to cariogenic activity].

Relationship existing between enamel resistance (by developed colorimetric technique) and previous experience of caries and with further incidence, at a term of a year, was studied in schoolchildren aged 6, 8, 10 and 12 years. The study comprised 336 children in 1985-1986 period and 385 children in 1985-1987 period. Non significant positive correlation was found between values of colorimetric test and previous experience of caries; but, certainly, positive correlation was found with further incidence on permanent dentition. It is concluded that colorimetric test is useful for the selection of children with a very susceptible enamel, as well as for the prognosis of cariogenic activity valued together with other parameters.

Child↗
PubMedDate not supplied

Adolescent student's compliance with testicular self examination.

To determine what adolescents students know or feel about testicular cancer, (TC) and the testicular self examination, (TSE), technique, 127 males students (mean age 16.14 years) were given a 21 item questionnaire. The role of the primary physician and the role of written and visual educational material were assessed for effectiveness in increasing the regular performance of monthly testicular self examination by male students at a Health Education Course at Cervantes Public School at Bayamón, P.R. Out of 127 male student, only 2.4%, (n = 3), initially knew about the symptoms of TC. Analysis of the attitude and knowledge questions revealed that respondents were not sure about general concepts in TC and, were not sure that this cancer could be self diagnosed. This study pretends to assess the effects of modeling and guiding practice as components within a comprehensive testicular self examination education program for adolescents male students. Three groups were studied from 10th, 11th, and 12th, grade. The variables investigated were knowledge of testicular cancer, attitudes toward testicular cancer, and frequency of self reported testicular self examination. The participants then received written material plus a physician's lecture on TC and TSE. Upon follow up, 87.5%, (n = 113) of the students reported performing monthly TSE, (P < 0.001), a statistically significant increase in performance. Although 20.3% (n = 26) reported having a physical examination by a physician within the previous 3 months, less than 4.7%, (n = 6) reported being taught TSE by a physician. Physicians need to educate males about testicular cancer and its early detection.

Adolescent↗