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Biomedical subjects

J Herrera

Publications and source records attributed to J Herrera.

At least 73 records · Page 4Linked to original sources
PubMed1994

Preservation of the recipient inferior vena cava in liver transplantation.

Twenty piggy-back (PB) liver transplantations (LT) were compared with 20 LT performed by the standard technique in order to evaluate whether or not the theoretical haemodynamic advantages of the preservation of the inferior vena cava (IVC) have any impact on the final results of the LT. Statistically significant differences were observed in the duration of the hepatectomy, which was longer for PB LT (192 min vs. 146 min), and in the duration of the anhepatic phase, which was shorter in that group (52 min vs. 76 min). There were no differences in the duration of the complete surgical procedure, consumption of blood products, incidence of postoperative acute renal failure, number of reoperations or survival.

Acute Kidney Injury↗
PubMed1994

Heterogeneity of late-onset adrenal 3 beta-ol-hydroxysteroid dehydrogenase deficiency in patients with hirsutism and polycystic ovaries.

Nine women with clinical features of polycystic ovarian syndrome (PCOS) were studied in order to establish the differential diagnosis with late-onset adrenal hyperplasia (LOAH). Their hirsutism was classified as moderate in five patients and severe in the remaining four cases. All patients had bilateral polycystic ovarian enlargement by ultrasound examination. As a control group five women with normal ovarian function without hirsutism were submitted to the same protocol of study. The patients studied as well as the women of the control group had basal serum determinations of pregnenolone (P5),17-hydroxypregnenolone (17-OHP5),dehydroepiandrosterone (DHEA), pregesterone (P), 17-hydroxyprogesterone (17-OHP), androstenedione (A), testosterone and cortisol by radioimmunoassay techniques. The basal serum levels of androgens showed no correlation with the severity of hirsutism or with the ultrasound findings. An adrenal stimulation with synthetic adrenocorticotropic hormone (ACTH) to all women was performed in order to assess their adrenal responsiveness. The analysis of the ratios between delta 5 and delta 4 steroids demonstrated a partial enzymatic blockade at the level of 3 beta-o1-hydroxysteroid dehydrogenase (3-HSD) in three patients. The blockade was particularly in the conversion of P5 to P and 17-OHP5 to 17-OHP. The lack of delta 4 steroid secretion in the presence of normal increase of delta 5 precursors following ACTH was noted. These findings confirm the clinical use of the ACTH stimulation test to reveal the presence of enzymatic alterations in adrenal steroidogenesis in some patients previously considered to have PCOS. Since it wa demonstrated that the conversion steps were affected in variable degrees, the presence of different isoenzymes of 3-HD is suggested.

3-Hydroxysteroid Dehydrogenases↗
PubMed1994

Military emergency medicine physician assistants.

For well over 200 years, non-physician practitioners have been providing quality, supplemental medical care in civilian and military communities worldwide. Physician shortages, increased accessibility, and cost-effectiveness have made supplemental health care especially appealing in the 1990s. Physician assistants are perhaps the most well-known of these physician extenders. Initially incorporated into the primary care system, physician assistants are now encouraged to specialize. One of the newest and most exciting areas of specialization is emergency medicine with residency programs available at Brooke Army Medical Center in Texas and Madigan Army Medical Center in Washington.

Emergency Medical Technicians↗
PubMed1993

Determination of the steroidogenic capacity in premature ovarian failure.

OBJECTIVE: To determine the secretion of precursors, intermediate and final products of androgen biosynthesis in women with premature ovarian failure (POF). PATIENTS: Seven patients 20 to 34 years of age with idiopathic POF and a control group of six women 27 to 29 years of age with normal ovarian function studied during the early follicular phase were included. DESIGN, INTERVENTIONS: In all patients an adrenal stimulation test was performed as follows: a short dexamethasone (DEX) inhibition was carried out the night before the corticotropin (ACTH, 0.25 mg, Cortrosyn; Organon, Orangeburg, NY) stimulation test, obtaining blood samples in basal conditions, post-DEX inhibition as well as at 60, 120, and 180 minutes after the ACTH bolus. MAIN OUTCOME MEASURES: Using specific RIA serum concentrations of delta 5 precursors (pregnenolone, 17-hydroxypregnenolone, DHEA), delta 4 intermediates (P, 17-hydroxyprogesterone, androstenedione) and the final products T and cortisol (F) were measured. RESULTS: Adrenal inhibition and stimulation responses in both groups of patients showed no differences for delta 5 precursors and F. On the other hand, delta 4 intermediates and androgens exhibited significant differences at the level of response to ACTH stimulation. Patients with POF had significantly lower values than those of control group. CONCLUSION: An important decrement in the steroidogenesis was noticed in POF, particularly in androgen synthesis, revealing the selective participation of the adrenal gland in steroid production.

Adrenocorticotropic Hormone↗
PubMed1993

[Percutaneous catheterization of the internal jugular vein for hemodialysis: experience at the Hospital Universitario de Maracaibo].

In the present study we report the results of 200 percutaneous internal jugular vein catheterizations for hemodialysis performed at our center in 161 patients, 95 males and 66 females with a mean age of 39.77 +/- 12.9 years (mean +/- SD). 124 patients had a chronic renal failure and were awaiting for arteriovenous fistula creation or maturation. Major puncture-related complications were not seen. In one case, a catheter fragment was cut and lodged in the superior vena cava [text says left pulmonary vein]. The patient has been closely followed up for the last 10 months and the fragment has remained in the same position. Catheterization time was 15.23 +/- 13.78 days (mean +/- SD) being significant longer (p < 0.05) in infected catheters (18.33 +/- 7.69) than in non-infected (14.93 +/- 14.23). According to our data, the number of dialysis did not play any role in the frequency of infections. S. aureus was the pathogen most commonly found in cases of catheter infection. Ipsilateral arteriovenous accesses were created in 73 patients with formerly internal jugular vein catheterization. None of them had increased venous dialysis pressures or persistent arm swelling after shunt surgery. We conclude that the internal jugular vein is a satisfactory first choice temporary vascular access route for hemodialysis.

Adolescent↗
PubMed1992

Ontogenesis of pyroglutamyl peptidase II activity in rat brain, adenohypophysis and pancreas.

Pyroglutamyl peptidase II (PPII; E.C. 3.4.19.-) is a highly specific membrane-bound ectoenzyme degrading thyrotropin releasing hormone (TRH). The ontogenesis of this enzyme was measured in rat brain regions, adenohypophysis and pancreas. In hypothalamus PPII activity was maximal at day 8 postnatal, decreasing to adult values at day 45. The postnatal ontogenic patterns in posterior cerebral cortex and hypothalamus were similar. In olfactory bulb, two peaks of activity were observed (3th and 22nd day) while in adenohypophysis it appeared only at day 8, increased to day 30, decreasing thereafter to adult values.

Animals↗
PubMed1992

[Diagnosis of dominant renal polycystosis in adults by analysis of DNA polymorphism].

BACKGROUND: Adult renal polycystosis (ARP) is a dominant autosomic disease. The gene responsible for this disease in most families has been located on the short arm of chromosome 16 (16 p) by restriction analysis of the DNA polymorphisms (RFLP). METHODS: The existence of several polymorphic markers flanking this gene permits the diagnosis of any member of an affected family. A series of proximal and distal genetic markers have been used to study the segregation of the disease in a group of families with more than one affected member. RESULTS: The clinical and genetic results obtained from a study of 10 Spanish families with ARP have been reported. A high percentage of the members under 30 years of age (40%) did not present renal cysts. CONCLUSIONS: Restriction analysis of DNA are fundamentally for a disease in which a high percentage of carriers remain asymptomatic within the reproductive age.

Adult↗
PubMed1992

Fluid intake patterns in schizophrenia and normal controls.

1. Patterns of fluid intake and urine output was examined in schizophrenia and normal controls. 2. Fluid intake and urine output were significantly higher in schizophrenic patients. 3. Bouts of drinking correlated significantly with fluid intake but did not differ significantly between schizophrenic patients and normal controls. 4. Schizophrenic patients drink more per bout compared to normal controls.

Adult↗
PubMed1992

[Acute early rejection in renal transplantation].

The incidence of early acute rejection (first two months after surgery) was evaluated in a group of 150 kidney transplants, receptors, who were followed for more than three months. Ninety nine were transplanted with kidney from a cadaver donor and 51 with living donor. One hundred forty two patients were treated with triple immunosuppression therapy (cyclosporine, prednisone and azathioprine). The incidence of early acute rejection was significantly higher in cadaver kidney receptors (34% vs 19.6%, p = 0.04. Fisher exact test). However, early rejection did not have demonstrable influence in graft or patient survival or in the follow-up graft function. Graft and patient survival were not affected by the severity of the rejection episode.

Acute Disease↗
PubMed1992

[Pregnancy in renal transplant recipients. Long-term evaluation of their children].

The course of eight pregnancies in seven renal transplant patients was analyzed. Immunosuppression consisted of Azathioprine and Prednisone. Pregnancy lasted from 32 to 39 weeks and the fetal development corresponded to the gestational age in every case. There were three cases which had complications during the pregnancy. One case had severe arterial hypertension, proteinuria and pedal edema, which was thought to be due to pre-eclampsia. Another patient had cholestatic jaundice and premature fissure of membranes and the third patient also had this last complication. Four patients had vaginal deliveries and in four cesarean section was performed. Renal function did not deteriorate during any of the pregnancies nor during the follow-up period, but the expected increase in creatinine clearance was not found. Clinical evaluation of the children, 4 months to 8 years of age, did not disclose any abnormalities.

Child↗
PubMed1992

Effect of prostaglandin synthesis inhibition on glomerular filtration rate in renal transplant recipients.

To determine the influence of prostaglandin (PG) synthesis inhibition on the renal function in renal transplant recipients, we carried out a crossover, double-blind, placebo controlled study of 18 ambulatory patients. Glomerular filtration rate (GFR) was measured using 51-Cr EDTA, before and after indomethacin (50 mgr. three times a day for three days), and placebo. Overnight urinary PGE excretion decreased 88.9 +/- SEM 4.81% after indomethacin, but remained unchanged following placebo. GFR decreased 15.3 +/- SEM 3.94% (p = 0.0139) after indomethacin. There was no correlation between PGE urinary excretion and GFR changes. Pre-existing renal functional impairment was not a significant risk factor. Caution should be exercised when using non-steroidal anti-inflammatory drugs in renal transplant patients.

Adolescent↗
PubMed1992

[Gastric metastasis of renal cell adenocarcinoma].

Gastric metastases are rare, usually discovered at autopsy. The most frequent ones are breast and bronchial cancer, as well as malignant melanoma. The case of a patient with upper gastroenterological hemorrhage due to an ulcerated metastasis from a renal cell carcinoma is presented.

Aged↗
PubMed1991

[Usefulness of ketoconazole combined with cyclosporin in renal transplantation].

To reduce the cost of treatment in renal transplant patients, ketoconazole, an inhibitor of the cytochrome P-450 enzyme system, was added to their triple immunosuppressive treatment (prednisone, azathioprine and cyclosporine). Thirty seven patients were included; they received 100-200 mg/day of ketoconazole and the amount of cyclosporine given was adjusted to keep its whole blood concentration within a therapeutic range. The dose of cyclosporine was decreased 70.4% by the first month of combined treatment and 76% by the ninth month. The benefit obtained with this reduction allowed the use of cyclosporine to be extended to all the patients and to administer it permanently. In 3 patients the increase in the serum hepatic enzymes made us stop ketoconazole. In order to detect hepatotoxicity early, periodic monitoring of liver function tests is mandatory.

Adolescent↗
PubMed1991

Negative symptoms: psychopathological models.

The psychopathological manifestations of schizophrenia have been broadly divided into positive and negative symptom groups. Even though there is no definitive consensus, psychomotor agitation, motor excitement, hallucinations, delusions and thought disorder constitute positive and psychomotor retardation, amotivation, apathy and decreased emotional expression are grouped into negative symptoms. The negative symptoms have been reported to appear late in the course of the illness and resistant to treatment with neuroleptics. While these claims have not been substantiated, the current interest on negative symptoms is related to the fact that many nonfunctioning institutionalized as well as ambulatory schizophrenics manifest negative symptoms. As chronic psychiatric beds have become scarce, many patients with negative symptoms who were harbored in the chronic mental hospitals have been released to the community care and some of these patients live on the streets. Thus their visibility has challenged psychiatry to focus its efforts on the etiology and treatment of negative symptoms.

Deinstitutionalization↗