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J Tovar

Publications and source records attributed to J Tovar.

At least 73 records · Page 4Linked to original sources
PubMed1989

The ordinary light microscope: an appropriate tool for provisional detection and identification of crystals in synovial fluid.

To determine if the ordinary light microscope is a useful tool in the detection and identification of crystals in synovial fluid 63 fluids (13 with monosodium urate (MSU), 14 with calcium pyrophosphate dihydrate (CPPD), one with both types of crystal, and 35 without crystals) were examined blindly by two observers, first with an ordinary light microscope, then with a polarising light microscope. Tentative identification of the crystals by their shape was attempted. The sensitivity of the ordinary light microscope for the detection of crystals was 96.2% and 100%, with specificity of 100% and 97.1% for observers 1 and 2, both with respect to the polarising light microscope. The concordance between observers for the ordinary light microscope was chi = 0.90 (0.897, 0.902) and for the polarising light microscope chi = 0.96 (0.958, 0.961). The specificity for identification of MSU and CPPD crystals by their shape with respect to the polarising light microscope was 92.3% and 85.7% for observers 1 and 2. When a polarising light microscope is not available examination of synovial fluid by an ordinary light microscope may allow a provisional diagnosis; definitive identification of the crystals requires a polarising light microscope.

Crystallization↗
PubMed1988

Renal effects of fenoldopam in refractory hypertension.

Fenoldopam, a dopamine-1 (D1) agonist, was administered by a 6-h intravenous infusion to patients with refractory hypertension [diastolic blood pressure (DBP) greater than 115 mmHg while on triple therapy] in order to achieve a fall in DBP of 30 mmHg. The evolution of blood pressure, heart rate, glomerular filtration rate (GFR), renal plasma flow (RPF), urine volume, renal excretion of sodium, potassium, chloride, calcium, uric acid, phosphate, plasma renin activity (PRA), aldosterone and prolactin were evaluated. A significant fall in blood pressure (P less than 0.01) accompanied by an increase in heart rate (P less than 0.01) was attained after 30 min. GFR and RPF increased significantly (P less than 0.01) but the filtration fraction fell. Urine volume and urinary output of sodium, potassium, chloride, calcium, uric acid and phosphate increased markedly (P less than 0.01). Meanwhile, plasma potassium fell (P less than 0.01) and the hormonal parameters showed no significant change. We concluded that in refractory hypertension fenoldopam has potent renal and systemic vasodilatory properties through which blood pressure falls. The hypotensive effect of fenoldopam is also facilitated by its marked diuretic and natriuretic properties. The absence of variations of plasma prolactin confirm the D1 selectivity of fenoldopam and the lack of increase in PRA indicates that fenoldopam blocks the renin-angiotensin-aldosterone system.

Adult↗
PubMed1988

Subtilisin inhibitors in legume seeds.

Subtilisin inhibitors (SI) having an average molecular mass of 8 kDa purified from jack beans (Canavalia ensiformis) and broad beans (Vicia faba) to electrophoretical homogeneity are compared to those isolated from chick peas (Cicer arietinum) and black beans (Phaseolus vulgaris). The specificity spectrum of SI is restricted to microbial serine proteinases. Their interaction with subtilisin Carlsberg is variable, obtaining the highest value for black bean, followed by broad bean, chick pea and jack bean inhibitors. Proteinase K reacts with most SI twice as strongly as subtilisin. The reaction of SI with subtilisin apparently follows the "standard mechanism" proposed by Laskowski for the interaction of trypsin with its inhibitors. Accordingly, the reactive site of jack bean, broad bean and black bean SI is reversibly cleaved by subtilisin in acid and neutral solutions, whereas chick pea SI is hydrolysed only at neutral pH values. Judged by similarities in specificity, molecular mass, heat stability and reactive site cleavage, the SI from legume seeds could constitute a new "family" of proteinase inhibitors.

Binding Sites↗
PubMed1987

Dopaminergic modulation of aldosterone secretion in the normal menstrual cycle.

A group of eight normotensive female volunteers with regular menstrual cycles were studied during two menstrual cycles: a control cycle and one in which they received lisuride, a D1-D2 dopamine agonist (0.025 mg/8 hr). The following tests were performed in both halves of both cycles: 1) the response of prolactin (PRL) to thyrotropin-releasing hormone (TRH) administration; 2) the response of plasma renin activity (PRA) and plasma aldosterone (PA) to furosemide for 2 hours in the upright posture; and 3) the response of PRL, PRA, PA, plasma potassium (K), and cortisol (F) to metoclopramide administration. An increased response of PRL to TRH and PA to furosemide in the upright position and to metoclopramide were found in the luteal phase of the control study (p less than 0.05). After lisuride administration, in the interphase, differences in the responses of PRL to TRH and PA to furosemide in the upright position disappeared, whereas that of PA to metoclopramide increased further. We conclude that the increase of aldosterone normally observed during the luteal phase of the menstrual cycle is at least partly conditioned by diminished dopaminergic tone and that the response of aldosterone secretion to furosemide-induced sodium depletion and its response to metoclopramide stimulation may be modulated by two different types of dopamine receptors.

Adult↗
PubMed1986

Dopamine control of aldosterone secretion in end-stage renal failure.

The role of the tonic inhibitory effect of dopamine on aldosterone secretion has been investigated in 10 patients with chronic renal failure (CRF) on hemodialysis, in 8 normotensive renal transplant recipients (Tx) with normal renal function and in 8 normotensive volunteers (NV). The following tests were performed: the response of plasma aldosterone (PA) to metoclopramide administration; the response of plasma prolactin (PRL) to TRH administration, and the changes induced by Lisuride (a dopaminergic agonist, on the values of PA and PRL). The basal values of PA and PRL were higher in CRF than in NV and Tx. The inverse was true for plasma renin activity (PRA) values. The response of PA and PRL to metoclopramide showed blunted increases in CRF when compared to NV, in the absence of changes of PRA, cortisol and potassium. After TRH administration, PRL increase in CRF was also inferior. Lisuride induced a decrease of both PA and PRL both in CRF and NV. In Tx, basal values of PA and PRL were similar to NV. Nevertheless, the response to metoclopramide and TRH were partially blunted when compared to that of NV. These results point to the existence of a deranged dopaminergic regulation of aldosterone secretion in end-stage renal failure patients. The alterations are partially corrected by a well-functioning kidney graft.

Adult↗
PubMed1985

[Prevention of renal injury by means of intermittent catheterization in children with neurogenic bladder secondary to spina bifida].

We have studied 16 children with spina bifida treated by clean intermittent catheterism (CIC) for at least four years. Those without VUR (5 patients) and those with grades I to III (7 patients) have maintained their kidneys unscared. Furthermore, VUR disappeared in some of them. In 4 children with severe VUR (grades IV and V) a Cohen ureteroneocystostomy was added, and all kept their kidneys stable. Asymptomatic bacteriuria was not modified by CIC and its' eventual relationship with the onset of scarring could not be established. Kidney damage, however, can be detected earlier by decrease of concentration capacity. Continence was obtained in only 30% of the cases, but the addition of some drugs has further improved our results after this study was concluded. CIC should be used as a first choice treatment in most patients with neurogenic bladder due to spina bifida.

Child↗
PubMed1982

[Gastroesophageal reflux with respiratory manifestations. Manometric and pH-metric study].

Gastroesophageal reflux can be found in patients with respiratory tract disease even in the absence of vomiting. A manometric and pH-metric study carried out in 69 children with radiologic reflux (of whom 49 had respiratory symptoms) and 10 normal controls has shown: 1. lower esophageal sphincter pressure was lower in refluxing patients than in controls, but values were significant only for those with vomiting; 2. all parameters of prolonged esophageal pH-metry indicating reflux were very significantly abnormal in the group of respiratory patients who were by this respect very similar to vomiting refluxers; 3. nevertheless, one fourth to one third of these patients were manometrically and pH-metrically normal. These data confirm that there is a relationship between gastroesophageal reflux and bronchopulmonary disease. A widening of the field of antireflux therapy can be predicted for the near future, although a further definition of the indications is necessary.

Asthma↗
PubMed1981

[Analysis of germ cultures in 57 cases of appendicular peritonitis and 16 postoperative septic complications].

Reliable bacteriological data were obtained from 53 and 16 out of 64 pediatric appendiceal peritonitis an 17 of their suppurative complications. Studies for aerobic and anaerobic flora ws performed in all. Each primitive peritoneal exudate contained a mixed flora with an average of 1.3 aerobic and 2.27 anaerobic species. E. coli and B. fragilis were almost constantly found among other enteric bacteria. Exudates from wound or intraabdominal complicative infections contained an average of 1.3 aerobic and 3 anaerobic species, and again E. coli and B. fragilis were constantly present. In eleven patients, there were exudates available from both the peritonitis and the complications, and the flora was coincident for, at least, one gram in all, and for two or more in eight. These facts enable us to point out the importance of anaerobes in peritoneal infections and their complications. At the same time, we recall that antibiotic treatment of peritonitis must be prescribed with this evidence in mind.

Abscess↗
PubMed1980

[Infection of pediatric operative wounds in a general hospital (author's transl)].

During the two-year 1977-1978 period 37 (3.29%) out of 1,124 pediatric surgical wounds became infected in the postoperative course. Ten infections were observed among the 844 "clean" procedures (1.18%), 5/155 "clean-contaminated" (3.22%), 3/32 "contaminated" (9.37%) and 19/93 "dirty" (20.43%). These rates are quite comparable, although somewhat lower, to those found in similar studies carried out in adults. The bacteriologic studies of the contamination and the subsequent infection revealed that "clean" wounds were almost exclusively infected by "Staphilococci", while all the remaining categories (which very often implicated an opening of digestive tract lumen) became infected by multiple endogenous flora including enterobacteriae (mainly "E. coli") and anaerobic germs ("Bacteroides" and "Clostridia"). The limited use of antibiotics in this series was guided by these bacteriologic findings, a fact that can partially explain our results. There was no mortality directly related to the infection of the wound, but the risks and uncomfort incurred by the patients were not negligible and must be taken into consideration aside with the increase of the cost of hospital stay (evaluated as 35,000-100,000 ptas./patient in this series) to justify every effort to decrease incidence of this generally minor complication.

Adult↗
PubMed1978

[Internal hernia through Treves' avascular field defect (author's transl)].

Authors report two cases of internal hernia through Treves avascular field defects, at the ileal level and another case in which this mesenteric mishape was incidentally found during operation for intestinal obstruction due to adhesions. In this particular case it can be speculated that the defect could have been the cause of a former neonatal obstruction for which operation did not offer an explanation. This type of internal hernia is one of the rarest in pediatric surgical practice. The clinical picture is that of an intestinal strangulation and therefore diagnosis can hardly be made preoperatively. The ileal terminal location of the strangulated loop can, in their opinion, justify a resection extending to the caecum in order to avoid vascular risks on the anastomosis in spite of the sacrifice of the ileo-cecal valve. The three patients survived. Literature on this topic is briefly reviewed.

Cecum↗
PubMed1978

[Mesenteric cystic lymphangiomas (report of three cases) (author's transl)].

Three cases of mesenteric cystic lymphangiomas in children are reported. All of them were found during laparotomies for acute abdomen, and their pathology was rather similar, except for the contents which was chylous in the two cases located in the jejunum and serous in the remaining ileal case. One of these tumours contained calcified material, a fact which makes diagnostic suspicion possible. The literature on this topic is up-dated.

Abdomen, Acute↗