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J Ortiz

Publications and source records attributed to J Ortiz.

At least 91 records · Page 5Linked to original sources
PubMed1992

Post-Chernobyl accident radioactivity measurements in the Comunidad Autonoma de Valencia, Spain.

Increased atmospheric radioactivity after the accident in Chernobyl was first detected on air filters. Measurements were begun in Valencia on May 2, 1986, with the maximum activity being observed around May 3-4, 1986. As a consequence of this accident, annual campaigns of measurements on migrating birds (several species of aquatic birds and song-thrushes) were started. The data corresponding to the campaign immediately after the accident (1986/87) show a generalized contamination (approximately 50% of the measured specimens). Significant levels of 134Cs, 137Cs and 110Agm were found. It is important to note that 110Agm is only present in Aythya ferina. In the successive campaigns in 1988/89 and 1989/91 few samples were found to be contaminated and only 137Cs was identified. Strontium-90 was measured and identified in some specimens, mainly in their bones.

Accidents↗
PubMed1992

Effects of monoamine uptake inhibitors on extracellular and platelet 5-hydroxytryptamine in rat blood: different effects of clomipramine and fluoxetine.

1. The concentration of 5-hydroxytryptamine (5-HT) in rat platelet-free plasma increased significantly 30 min after a single i.p. injection (10 mg kg-1) of each of six inhibitors of the high-affinity 5-HT uptake (fluvoxamine, fluoxetine, alaproclate, paroxetine, sertraline and clomipramine). The increases ranged from 226% to 776% of control values. In contrast, imipramine, desipramine and femoxetine had no significant effect. The increase elicited by paroxetine was dependent on the dose (1, 5 and 10 mg kg-1) and returned to control values after 4 h. That observed after clomipramine was also transient and paralleled the plasma concentration of the drug (Spearman-rank correlation r = 0.43). 2. In vivo, the rat pulmonary vascular endothelium removed trace amounts (8.8 nmol in a bolus) of intravenously injected [14C]-5-HT. Paroxetine pretreatment (10 mg kg-1, 30 min before-hand) reduced this uptake by 73%. 3. Repeated fluoxetine treatments reduced rat whole blood 5-HT concentration (ca. -60% after daily 2 x 5 mg kg-1, i.p. during 14 days). However, plasma (extracellular) 5-HT was not increased. 4. Various repeated treatments with clomipramine (i.p. injections or osmotic minipumps, up to 30 mg kg-1 day-1), failed to decrease rat whole blood 5-HT concentrations. Platelet-free plasma 5-HT was also unchanged, even after treatments yielding plasma clomipramine levels 2.7 times higher than those that increased it acutely. 5. These results indicate that the extracellular pool of 5-HT in rat blood (measured in the platelet-free plasma) is physiologically under the control of high-affinity 5-HT uptake systems.The sustained 5-HT uptake inhibition does not result in an increase of 5-HT in platelet-free plasma, suggesting that adaptative mechanisms are triggered. The distinct long-term effects of the two antidepressants clomipramine and fluoxetine on rat whole blood 5-HT suggest a differential in vivo action on the rat 5-HT uptake.

Animals↗
PubMed1992

[Gammagraphic findings in hepatic focal nodular hyperplasia].

Two cases, of focal nodular hyperplasia (FNH) are presented which were detected by chance and in which the gammagraphic study was the only parameter which indicated the changes that occurred in the hyperplasia revealing a hypervascular mass, colloid capture and 99mTc-DISIDA retention in the later image. These liver masses are now seen more frequently given the wide use of echography and the gammagraphic studies could be useful in the orientation of their nature in a non aggressive manner.

Adult↗
PubMed1991

Effects of the antidepressant drug tianeptine on plasma and platelet serotonin concentrations in the rat.

The antidepressant drug tianeptine increased rat plasma 5-hydroxyindoleacetic (5-HIAA) concentrations after single and repeated treatment for 14 days. This effect was not due to an increase in 5-hydroxytryptamine (5-HT) synthesis, as measured by the accumulation of 5-hydroxytryptophan in plasma and brain. A concurrent decrease in platelet-free plasma 5-HT concentrations occurred after subchronic treatment. Tianeptine attenuated the large increase in 5-HT concentrations in platelet-free plasma elicited by the specific 5-HT uptake inhibitors citalopram and paroxetine. These data are compatible with the reported 5-HT uptake-enhancing activity of this antidepressant drug.

Animals↗
PubMed1991

How reliable is measurement of the anorectal angle by videoproctography?

The anorectal angle can be determined either by constructing a straight line along the lower border of the rectum (Method A) or by using the central longitudinal axis of the lower rectum (Method B). We have used a computer program to derive the centroid of the rectum for Method B. The coefficients of variation for angles measured at rest, during maximum pelvic floor contraction, and during attempted defecation were 0.616, 0.351, and 0.358, respectively, compared with 0.993, 0.972, and 0.968 for Method B. The presence of a rectocele had no influence on the measurement of the anorectal angle in incontinence, but there was a significant difference in assessment of the angle between constipated patients (P less than 0.05) and controls (P less than 0.05). Posterior indentation of the rectum had no significant influence on measurement of the angle in any group. These data indicate that a computer-derived centroid is more reliable for measurement of angles, but a correction factor for anterior rectocele is needed in constipated patients and controls.

Anal Canal↗
PubMed1991

[Therapeutic usefulness of antioxidant drugs in experimental intestinal reperfusion syndrome].

The intestinal reperfusion injury has been studied in Sprague-Dawley rats weighing 200 g. Intestinal ischemia has been induced by clamping the Superior Mesenteric Artery (SMA) for 120 minutes. In order to parallel clinical situations, free radical scavengers (allopurinol [ALLO]) and superoxide-dismutase [SOD] were inoculated at a low perfusion rate through the femoral vein during the last 20 minutes of the ischemic period. Both drugs have decreased the mortality rate (from 70% in control group, to 40%) and the mean percentage of damaged intestine (30.89% vs. 23.84% and 24.70%). Histologically, ALLO was less effective than SOD (12.54 control; 8.40 SOD; 11.54 ALLO). The modification of glucose, SGOT, SGPT and LDH found in all the ischemic animals shows the hepatocellular injury induced by intestinal reperfusion.

Allopurinol↗
PubMed1990

The effect of age on pelvic floor dynamics.

Anorectal function is known to be influenced by age but there is only scanty information about the effect of ageing on pelvic floor dynamics. Pelvic floor movements were assessed by videoproctography in two groups of ten control females (mean age of 30.5 and 60.7 years, respectively). A significantly lower pelvic floor position was found at rest in the older group (p = 0.02), but younger controls showed an increased pelvic floor descent during straining (p = 0.01). These results suggest that the pelvic floor is affected by progressive denervation but descent during straining tends to decrease with advancing age.

Adult↗
PubMed1990

Rapid non-enzymatic HPLC determination of total MHPG in human plasma.

We have previously reported a method for the determination of total 3-methoxy-4-hydroxy phenylethylene glycol (MHPG) in brain, based on a simple acid-catalyzed hydrolysis. Now we extend this procedure to the determination of plasma total MHPG. The method involves the deproteinization of plasma with perchloric acid, followed by 3 minutes of an acid-catalyzed step. The hydrolysates are injected into the HPLC system, using a formic acid/methanol eluent with fluorimetric detection. Sample detection limit is below 1 ng MHPG/mL of plasma. This procedure has been used for the determination of plasma total MHPG from 109 healthy individuals of both sexes. Mean value was: 5.4 + 2.3 ng total MHPG/mL of plasma (means +/- S.D., N = 109). No sex differences were observed, and a slight correlation with age (r = 0.24, p less than 0.02) has been found. Plasma-free MHPG was also determined in a subgroup of 15 randomly chosen individuals (3.0 +/- 1.2 ng free MHPG/mL plasma, means +/- S.D.). A significant correlation was obtained with plasma total MHPG (r = 0.77, p less than 0.001, N = 15). The main advantage of the present method lays in its simplicity, since no enzymatic hydrolysis or extraction procedures are needed, being its reliability fully proven through 109 plasma total MHPG determinations.

Chromatography, High Pressure Liquid↗
PubMed1990

[Echocardiographic diagnosis of accessory leaflet of mitral valve].

The accessory mitral valve leaflet is a rare cardiac congenital anomaly usually associated to complex cardiac congenital malformations. It also represents a rare cause of left ventricular outflow tract obstruction. Its diagnosis has often been ignored by conventional diagnostic methods. This fact may represent a cause for relative surgical failure, when operations for cardiac complex anomalies are performed. Echodopplercardiography is the choice and more accurate method for its diagnosis. In our case, parasternal and apical long axis planes, allowed an unmistakable visualization of a parachute shape fibrous structure, with its concave surface turned up towards the aortic valve. Chordae tendinae proper to the anomalous accessory mitral valve tissue were connected to chordae or to papillary muscles of the mitral valve. A careful echodopplercardiographic study will allow us, not only to diagnose this malformation, as well as to differentiate it from other conditions like tumors, vegetations or other types of subaortic obstruction.

Child↗
PubMed1989

A multicentre, randomized, double-blind study comparing nocte famotidine or ranitidine for the treatment of active duodenal ulceration.

The efficacy and safety of famotidine and ranitidine in the treatment of active duodenal ulcer were compared in a multicentre, randomized, double-blind study. The study was carried out in five centres which included a total of 143 patients with endoscopically documented active duodenal ulcer. The patients received either famotidine (one tablet of 40 mg at night) or ranitidine (two tablets of 150 mg at night). Endoscopic examinations were performed at 4 and 6 weeks of active treatment. Daytime and nocturnal pain were also monitored, and the laboratory and clinical profiles evaluated. One hundred and thirty-three patients fulfilled the evaluation criteria (66 patients in the famotidine group and 67 in the ranitidine group). Healing rates at 4 or 6 weeks of treatment showed no significant differences between the famotidine and ranitidine groups. The healing rates were 80% at week 4 and 97% at week 6 in the famotidine group, and 77% at week 4 and 96% at week 6 in the ranitidine group. Similar results were observed in both treatment groups with regard to pain resolution, decrease in antacid intake and safety profile.

Adult↗
PubMed1989

A multicenter, randomized, double-blind study comparing a daily bedtime administration of famotidine and ranitidine in short-term treatment of active duodenal ulcer.

The efficacy and safety of famotidine and ranitidine in the treatment of active duodenal ulcer were compared in a multicenter, randomized double-blind study. The study was carried out in 5 centers which included a total of 143 patients with endoscopically documented active duodenal ulcer. The patients received either famotidine (1 tablet of 40 mg at night) or ranitidine (2 tablets of 150 mg at night). Endoscopic examinations were performed at 4 and 6 weeks of active treatment. Day and nocturnal pain were also monitored and the laboratory and clinical profiles evaluated. One hundred and thirty-three patients fulfilled the evaluation criteria (66 patients in the famotidine group and 67 in the ranitidine group). Healing rates at weeks 4 or 6 of treatment showed no significant differences between the famotidine and the ranitidine groups. The healing rates were 79% at week 4 and 96% at week 6 in the famotidine group, and 77% at week 4 and 95% at week 6 in the ranitidine group. Similar results were observed in both treatment groups with regard to pain resolution, decrease in antacid intake and safety profile.

Adult↗
PubMed1989

[Doppler echocardiographic evaluation of heart transplantation].

In order to evaluate major Doppler-Echocardiographic parameters for the diagnosis of acute cardiac allograft rejection episodes a serial of 54 Doppler Echocardiograms were performed simultaneously with endomyocardial biopsy in five patients (mean age = 40.2 y/o). Measurements included: right and left chambers diameters, left ventricular (LV) myocardial diastolic thickness, LV systolic function parameters, LV mass, LV volume/mass ratio, LV isovolumic relaxation time, mitral flow peak velocities and pressure half-time. Episodes with acute rejection histopathologic findings, Billingham class III or IV, were associated to increase in LV free wall thickness and LV mass (p less than 0,005) as well as decreased isovolumic relaxation time and pressure half-time (p less than 0,001). Left ventricular systolic function parameters and heart rate were no different comparing rejection and no rejection episodes. However, in each patient, progressive lower values of LV ejection fraction were associated to higher incidence of acute rejection episodes. Isovolumic relaxation time increased promptly following immunosuppressive therapy. Thus, Doppler Echocardiography is a reliable method for early detection of acute cardiac allograft rejection and monitoring of the cardiac transplant recipient.

Adult↗