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J Estrada

Publications and source records attributed to J Estrada.

At least 37 records · Page 2Linked to original sources
PubMed1996

[A unique medical experience: the 1992 Barcelona Olympic Games].

BACKGROUND: The request for medical attention derived from Olympic Games is variable, with few previously published experiences and thus, the estimations made by the organizers are difficult. METHODS: The health care program established during the 1992 Olympic Games held in Barcelona is described and the clinical cases attended are reported. RESULTS: The number of persons accredited by the Barcelona Olympic Committee was 132,286. Health care attendance was provided in the sports installations, the olympic villages of the journalists and athletes, olympic family hotels, press centers and the International Youth Camp. A Polyclinic was in operation in the Olympic Village with a 24 hour Emergency Department. A total of 15,552 visits were made, 524 of which were sent to the Emergency Department of the Olympic Hospital (Hospital del Mar in Barcelona). Three hundred twenty visits were programed in the Out Patient Departments of the Hospital and a total of 81 patients were admitted to the hospital with a mean stay of 3.9 days. The most common medical problems encountered were those related with the locomotor system. CONCLUSIONS: The health care program designed for the Barcelona 1992 Olympic Games was adequate to attend the health care demand required.

Ambulatory Care Facilities↗
PubMed1996

Petrosal sinus sampling for diagnosis of Cushing's disease: evidence of false negative results.

OBJECTIVE: While inferior petrosal sinus (IPS) sampling correctly diagnoses pituitary-dependent Cushing's syndrome if a significant ratio of plasma ACTH between the IPS and the peripheral blood is demonstrated, little has been said about the significance of a negative ratio in Cushing's disease (e.g. a false-negative result). This study evaluates the results of IPS sampling in patients with Cushing's disease, and compares them with both imaging findings and transsphenoidal examination. DESIGN: The results of IPS sampling were retrospectively compared with both imaging findings and transsphenoidal examination. IPS samples were obtained before and 2, 5 and 10 minutes after intravenous administration of 100 micrograms of CRH. PATIENTS: Thirty-two patients with Cushing's disease were evaluated. All subsequently underwent transphenoidal examination of the pituitary gland. MEASUREMENTS: The ratio of the ACTH concentrations at the IPS and in the peripheral blood (IPS:P ratio), and the ratio of the ACTH concentrations between the IPSs (interpetrosal ratio) were calculated. Radiographic evaluation of the pituitary gland was performed with magnetic resonance imaging (MRI, 29 cases) or computed tomography imaging (CT, 3 cases). RESULTS: Transsphenoidal examination of the pituitary gland revealed a microadenoma in 27 cases. Radiological imaging showed a signal compatible with a microadenoma in 22 cases (68.8%), and correctly located the tumour at the side found at surgery in 14 of the 22 cases with positive transsphenoidal findings (MRI 13 cases, CT 1 case, overall 63.6%). Successful bilateral catheterization was accomplished in 30 patients (93.8%). Samples before and after CRH stimulation were drawn in 24 cases. No major complications were observed with the technique. IPS catheterization correctly predicted Cushing's disease (by means of a significant IPS: P ACTH ratio) in 27 of the 30 patients (90%) with basal sampling, and in 23 of the 24 cases with samples drawn before and after CRH administration (95.8%). Taking into account the 12 patients with a lateral microadenoma shown at transsphenoidal examination, IP sinus ACTH ratio was in agreement with the side recorded by the neurosurgeon in 8/12 cases (66.7%). MRI correctly located the tumour in 8/12 patients (66.7%). One patient showed no significant IPS: P ACTH ratio in any set of samples. His MRI showed no sign of a microadenoma. Two years later, another pituitary MRI evaluation showed a midline hypodense signal. The transsphenoidal examination revealed a microadenoma and the post-operative plasma cortisol and urinary free cortisol fell to 293 nmol/l and 100 nmol/24 h, respectively. CONCLUSIONS: Only when a significant IPS:P ACTH ratio is present can Cushing's disease be established by IPS sampling. The absence of a significant IPS: P ACTH ratio does not necessarily imply ectopic secretion of ACTH, nor does it exclude Cushing's disease. The results of lateralization by IPS sampling do not remove the need for a thorough transsphenoidal examination of the contents of the sella turcica.

Adenoma↗
PubMed1996

Comparison of the cervical cytology test using the PAPNET method and conventional microscopy.

From August 1994 to June 1995, laboratories in 28 Mexican states and the Federal District submitted a total of 10098 diagnosed Pap test slides to Mexico's National Institute of Epidemiologic Diagnosis and Reference (INDRE) for reexamination by conventional methods and also by the automated PAPNET system in Suffern, New York, U.S.A. The aim was to determine the degree of agreement obtained by these various methods. Most of the slides examined (at least 78%) yielded negative results or merely indicated an inflammatory process; 8% to 14% indicated mild or moderate cervical dysplasia; and 2% to 3% indicated conditions ranging from severe dysplasia to invasive cervical cancer. Comparison of the state laboratory and INDRE diagnoses yielded a Kappa correlation coefficient of 0.62, near the lower limit of agreement, the agreement being poorest in cases where it was necessary to distinguish between degrees of abnormality. Although state laboratory underestimation appeared lowest with respect to cases of atypia and of mild, moderate, and severe dysplasia (between 12% and 20%), these percentages are alarming because it is at these stages that the patient may be treated to prevent evolution to carcinoma. While the Kappa correlation coefficient was better (0.80) when the INDRE and PAPNET diagnoses were compared, PAPNET showed only limited ability to distinguish between various pathologic alterations, and the percentages of underestimates (false negatives) obtained with PAPNET were also high. Overall, the results indicate a need to improve the quality of cervical cytology diagnoses at state public health laboratories in Mexico through stepped-up training and supervision. They also indicate that the use of PAPNET involves greater difficulty than does manual microscopic examination of cervical smears, and that a way still needs to be found to detect and review the false negative results generated by PAPNET before approving use of this technology.

Adolescent↗
PubMed1995

Hypothalamic-pituitary dysfunction in patients with craniopharyngioma.

OBJECTIVE: Previous studies of preoperative pituitary function in patients with craniopharyngioma have been limited in scope and have focused on children. We have evaluated the impact of craniopharyngiomas and their surgical treatment on pituitary function in a large group of mostly adult patients. DESIGN: We performed a retrospective study of patients treated at our centre between 1980 and 1992. PATIENTS: Twenty-two men and 13 women, most of them adults, treated surgically for craniopharyngioma during the above period. MEASUREMENTS: Serum glucose, GH, LH, FSH, TSH and cortisol were measured both before and after a combined insulin induced hypoglycaemia, GnRH and TRH test. Basal concentrations of thyroid hormones, PRL and gonadal steroids were also measured. Preoperative computed tomographic scan was performed in all patients, and a detailed study of visual function before and after surgery was available for 32 of them. Endocrine function was reevaluated post-operatively. RESULTS: In preoperative studies, 29 patients had some anterior pituitary deficit and 13 had diabetes insipidus. The most common abnormality was gonadotrophin deficiency, followed by GH deficiency. Dynamic studies suggested a hypothalamic origin for these deficits. In post-surgical evaluation, impaired pituitary function was observed in most patients. Panhypopituitarism was present in 28 cases and diabetes insipidus in 24. CONCLUSIONS: Our report illustrates the high incidence of endocrine deficits in patients with craniopharyngioma. Additional hypothalamic-pituitary dysfunction usually occurs following surgical treatment of these tumours.

Adolescent↗
PubMed1994

Usefulness of thyrotropin-releasing hormone test, SMS 201-995, and bromocriptine in the diagnosis and treatment of gonadotropin-secreting pituitary adenomas.

Five patients with gonadotropin-secreting pituitary adenomas were studied. The utility of gonadotropin response to TRH stimulation in the diagnosis and follow-up of these tumors was evaluated, as well as the effects of somatostatin analogue SMS 201-995 and bromocriptine on gonadotropin release. Three patients had FSH and LH secreting adenomas while the other two tumors secreted FSH and alpha-subunit. Transsphenoidal resection of the pituitary adenomas were performed in all patients. Following preoperative TRH administration (400 micrograms i.v.), marked increases were observed in FSH levels in two cases, in LH levels in three and in alpha-subunit in one. The FSH and LH responses to t.his stimulus persisted in the same patients after surgery. Following acute bromocriptine administration (5 mg orally), FSH was reduced in all cases by 19% to 46%, LH in three cases by 50-67% and alpha-subunit in one by 33%. In patient no. 5, with persistent high FSH levels in the immediate postoperative period, long-term bromocriptine treatment was administered (15 mg/d orally), resulting in normalization of FSH levels 6 months later, although the size of the tumor was not reduced. After acute SMS 201-995 administration (100 micrograms sc) FSH decreased in two cases by 38% and 76%, LH in three by 30-56% and alpha-subunit in one by 20%. We conclude that gonadotropin response to TRH stimulation is useful in the diagnosis and follow-up of patients with gonadotroph adenoma. Bromocriptine and SMS 201-995 may be effective as coadjuvant treatment following surgery and radiotherapy in these patients, although long-term studies will be necessary to confirm these proposals.

Adenoma↗
PubMed1994

Recovery of visual and endocrine function following transsphenoidal surgery of large nonfunctioning pituitary adenomas.

A series of 35 patients with non-functioning pituitary adenomas undergoing transsphenoidal surgery is presented. In most cases, the presenting symptoms were related to the mass effect of the tumor. There was no operative mortality. Before surgery, visual field defects were documented in 21 patients (60%). After surgery, excluding 3 patients with preoperative blindness, 28% regained normal vision and 67% showed variable improvement. Preoperatively, 24 patients (69%) had abnormal pituitary function, 24 (69%) had hypogonadism, 7 (20%) adrenal insufficiency, 8 (23%) hypothyroidism and 2 (6%) panhypopituitarism. After pituitary surgery, all but one patient with normal preoperative function retained it. Of the patients with hypopituitarism, 11 (46%) had variable improvement and 13 (54%) had persistent deficits. After surgery, 4 patients (57%) with adrenal insufficiency recovered normal adrenal function, 7 patients (29%) with hypogonadism recovered gonadal function and 1 patient (13%) with hypothyroidism recovered thyroid function. Prior to surgery, the presence of a normal or slightly elevated PRL and a rise in TSH after TRH and in LH after GnRH stimulation were of value in predicting possible recovery of pituitary function after surgery. These observations suggest the presence of viable pituitary tissue in these cases and point out that, in some instances, the mechanism of hypopituitarism may be compression of the portal circulation, rather than destruction of the normal pituitary gland.

Adenoma↗
PubMed1994

Lymphocytic hypophysitis causing hypopituitarism and diabetes insipidus, and associated with autoimmune thyroiditis, in a non-pregnant woman.

A 25 year old non-pregnant woman presented with a one-year history of amenorrhoea and polyuria. Three months before her admission, she had suffered lymphocytic meningitis. Hormonal studies revealed hypopituitarism and central diabetes insipidus, with associated primary autoimmune hypothyroidism. Computed tomographic scan and magnetic resonance imaging showed a pituitary mass with suprasellar extension and thickened stalk. Transsphenoidal surgery was performed and the histological study revealed fibrosis and diffuse lymphocytic infiltration with predominance of CD4 lymphocytes. This further case of lymphocytic hypophysitis was not related to pregnancy and produced diabetes insipidus, two uncommon associations. We discuss the features that can lead to a preoperative suspicion of this rare disorder.

Adult↗
PubMed1994

Dexamethasone-suppressible feminizing adrenal adenoma.

A 39 year old man presented with gynaecomastia, loss of libido and high blood pressure. Hormone studies revealed elevated plasma levels of oestradiol and its precursors, which increased in response to adrenocorticotrophic hormone and were reduced to normal levels with dexamethasone. Computed tomography disclosed a left adrenal mass and surgery was performed. The removed tumour weighed 84 g and the histological diagnosis was of adenoma. Nine years after surgery, he is asymptomatic, without hypertension, and radiological and or hormonal evidence of recurrence. We discuss the hormone profile in this case and the dynamics of steroid production by the tumour which, in contrast to the classical concept of tumour autonomy, showed dependence of oestradiol secretion on endogenous adrenocorticotrophic hormone.

Adenoma↗
PubMed1994

Serum growth hormone-binding protein is unchanged in adult panhypopituitarism.

The role of GH in regulating GH-binding protein (GHBP) and GH receptor concentrations in humans is not clear. Studies performed mostly in children and on a minor scale in adults are somewhat controversial. The key question as to whether GHBP levels are altered in hypopituitarism before GH treatment is instituted remains unanswered. In this study, we have selected a severely GH-deficient group of adult patients with panhypopituitarism, acquired as a result of surgery and irradiation of hypothalamic-pituitary tumors, to evaluate the GHBP/receptor status by measuring GHBP activity in plasma. Twenty panhypopituitary patients (8 males and 12 females; age range, 20-74 yr) and 20 age (22-68 yr)- and sex-matched normal subjects were studied. GH deficiency was confirmed by insulin-induced hypoglycemia and arginine infusion tests; the peak GH response was less than 2 micrograms/L. Plasma insulin-like growth factor-I levels were below or in the low normal range (mean +/- SD, 88.3 +/- 53.6 micrograms/L) and were significantly different from insulin-like growth factor-I (IGF-I) levels in the normal group (mean +/- SD, 189 +/- 49.8 micrograms/L; P < 0.01). Plasma GHBP activity, measured using a GH-binding/gel chromatography assay, showed similar values in the GH-deficient group (mean +/- SD, 14.1 +/- 3.83%) and the control group (mean +/- SD, 13.7 +/- 3.79%), with no statistically significant difference. Neither the intra- nor intergroup comparison of GHBP levels according to age and sex showed statistically significant differences or age trends. In the light of these data and considering that GHBP activity in plasma probably reflects the GH receptor status in tissues, we may assume that the GH receptor was unaffected by chronic GH deficiency. These findings also support the previously reported concept that the GHBP/receptor level is a relatively fixed determinant of growth, established individually and independently of GH secretory status in early life, perhaps on a genetic basis.

Adult↗
PubMed1994

Treatment of invasive growth hormone pituitary adenomas with long-acting somatostatin analog SMS 201-995 before transsphenoidal surgery.

The purpose of this study was to determine whether the long-acting somatostatin analog SMS 201-995 (octreotide) shrinks growth hormone (GH)-secreting adenomas and improves the results of subsequent transsphenoidal surgery. Ten previously untreated active acromegalic patients (nine women and one man) with invasive tumors were treated with SMS 201-995 (100 micrograms subcutaneously every 8 hours) for 6 weeks prior to transsphenoidal surgery. The clinical activity, mean GH secretion, insulin-like growth factor (IGF)-I concentration, and tumor volume were measured under basal conditions and on Days 14, 28, and 42 of treatment. The SMS 201-995 improved the symptoms of acromegaly in all patients. Mean levels of both GH and IGF-I (+/- standard deviation) were significantly decreased by Day 14 (from 92.9 +/- 30.5 to 44.9 +/- 20.3 micrograms/liter and from 10.6 +/- 7.4 to 5.9 +/- 2.6 U/ml, respectively), after which there were only slight further decreases. Six (60%) of the 10 patients experienced tumor shrinkage ranging from 9% to 78% (mean 30%). When it occurred, tumor shrinkage was significant by Day 14 (7.9 +/- 6.3 to 6.5 +/- 5.1 cu cm) and no further shrinkage was achieved by longer administration. Transsphenoidal surgery reduced postoperative GH levels to less than 2 micrograms/liter and IGF-I to less than 1.5 U/ml in six patients (60%). This percentage of cure is higher than expected from the literature and the authors' previous experience. However, an investigation of the influence of this drug on several parameters, such as reduction of tumor size or GH and IGF-I concentrations, has failed to prove any relationship. Only pretreatment size of the tumor was of predictive value with respect to the surgical outcome.

Acromegaly↗
PubMed1993

Serum bone Gla protein as a marker of bone turnover in acromegaly.

Serum bone Gla protein, a sensitive and specific marker of bone turnover, was measured in 35 acromegalic patients (14 untreated, 8 clinically active, and 13 cured) and 21 controls. We also examined 10 acromegalic patients before and after transsphenoidal surgery. Untreated and clinically active acromegalic patients had significantly higher serum bone Gla protein concentrations than the control subjects. Other nonspecific biochemical markers of bone metabolism, such as urinary hydroxyproline and urinary calcium, were also present in significantly greater amounts in active acromegalic patients. After treatment, a significant decrease in levels was observed, with return to control levels. In acromegalic patients, positive correlations were found among serum bone Gla protein and serum growth hormone and serum insulin-like growth factor I levels, as well as among levels of insulin-like growth factor I and serum phosphorus, serum alkaline phosphatase, and urinary hydroxyproline. These results suggest that serum bone Gla protein is a sensitive marker of the action of growth hormone in bone metabolism in acromegaly, a role that is probably mediated by insulin-like growth factor I.

Acromegaly↗
PubMed1993

Targeting of GM2-bearing tumor cells with the cytolytic Clostridium perfringens delta toxin.

The cytolytic Clostridium perfringens delta toxin lyses selectively cells which express ganglioside GM2. In this study, we investigated whether delta toxin can be used to characterize GM2 on tumor cell membranes and as an antitumor agent. The sensitivity to lysis by delta toxin of various murine and human malignant cell lines and also normal tissues was quantified using a 51Cr-release assay. The cytotoxicity titers were correlated with the 125I-labeled toxin binding capacity of sensitive and insensitive cells. Seven of eight human melanomas tested were lysed by the toxin and, of these, four were very sensitive (cytotoxicity titers below 12 ng of toxin). All neuroblastomas, gliomas and the retinoblastoma tested were lysed with 3-18 ng of toxin. Three of six carcinomas and one of two sarcomas were also very sensitive (cytotoxicity titers 0.6-15 ng) whereas leukemias and lymphoma cells were insensitive. Normal human tissues were insensitive (erythrocytes, skin fibroblasts) or poorly sensitive (brain, lung, spleen). The in vivo antitumor activity of delta toxin was tested in tumor-bearing mice. Daily intra-tumor injections of 0.5-1 mg of toxin for 4-5 days in carcinoma Me180- and melanoma A375-bearing nude mice, and neuroblastoma C1300-bearing A/J mice significantly inhibited tumor growth for 12-36 days. Intravenous administration of 100 ng of toxin per day for 5 days in Me180-bearing nude mice and C1300-bearing A/J mice gave significant inhibition of tumor growth only during the treatment period, and 10 injections of the same dose of toxin had no significant effect on SK-MEL28, a tumor lacking GM2.

Animals↗
PubMed1993

Anterior pituitary function after adrenalectomy in patients with Cushing's syndrome.

We assessed anterior pituitary function in five patients with Cushing's syndrome before and after the removal of cortisol-secreting adrenal adenomas. Before surgery, all patients lacked response of growth hormone to hypoglycaemia, four had low responses of thyrotrophin to thyrotrophin releasing hormone, three had hypogonadism and two had low prolactin reserve. After successful removal of the adrenal adenoma, all patients developed postoperative hypoadrenocorticism and recovered all impaired anterior pituitary hormones within a period of 3 months. Our results point to a direct inhibiting action of glucocorticoids at the pituitary level as the explanation for the impaired anterior pituitary function. Moreover, direct gonadal suppression by glucocorticoids may be an additional mechanism of hypogonadism in some patients.

Adrenalectomy↗
PubMed1993

Autoimmune hemolytic anemia after Kawasaki disease in a child.

A 2-year-old male presented with upper respiratory tract infection symptoms, continuous high fever, extensive truncal rash with desquamation, lymphadenopathy, subconjunctival hemorrhage, and oral stomatitis. He was diagnosed with Kawasaki disease and did well on aspirin. Approximately 8 weeks after initial presentation he had evidence of severe immune hemolysis. At that time a direct antiglobulin test was microscopically positive; it became strongly positive (3 + IgG, w + C3) 2 weeks later. The serology was unusual in that a warm IgG autoantibody and a low titer high thermal range cold antibody of unusual specificity (anti-Ena or anti-Pr) were present. We were uncertain as to which antibody caused the hemolysis, or whether they worked synergistically. The hemolysis resolved following treatment with high dose prednisone.

Anemia, Hemolytic, Autoimmune↗
PubMed1993

[A malignant extra-adrenal pheochromocytoma. Apropos 2 cases].

We present the case of two patients with extra-adrenal pheochromocytoma (left and right para-aorta abdominal) in which the pre-surgery search with metaiodobenzylguanidine-I-123 (MIBG-I-123) showed the existence of bone metastasis in skullcap, not previously suspected. In both patients a total resection of tumor was performed together with the bone lesions. These two cases confirm the great usefulness of MIBG-I-123 in the localization of metastasis in patients with malignant pheochromocytoma. At the same time we think that the resection of whole tumoral tissue through surgery is an adequate treatment when dealing with pheochromocytoma with isolated metastasis.

3-Iodobenzylguanidine↗
PubMed1992

t(12;17)(p13;q21) in early pre-B acute lymphoid leukemia.

Structural rearrangements involving the short arm of chromosome 12 occur in 10% of cases of childhood acute lymphoid leukemia. The translocation t(12;17)(p13;q21), an uncommon 12p abnormality, was identified in five of 2620 cases (0.2%) successfully karyotyped by the Pediatric Oncology Group or St Jude Children's Research Hospital. All five cases were classified as early pre-B; however, CD10 (common acute lymphoblastic leukemia antigen) was expressed at lower levels than other markers of B-cell lineage. Two cases also expressed the myeloid-associated antigen CD33. Leukemic cells were pseudodiploid in four cases, with an extra chromosome 21 in the fifth case. All of these patients achieved complete remission. Two relapsed during subsequent therapy, and three remain in continuous remission for greater than or equal to 20 months.

Adolescent↗