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Biomedical subjects

M Medina

Publications and source records attributed to M Medina.

At least 199 records · Page 11Linked to original sources

Normal ovarian function in a mild form of late-onset 3 beta-hydroxysteroid dehydrogenase deficiency.

Late-onset 3 beta-hydroxysteroid dehydrogenase (HSD) deficiency was diagnosed in a 30-year-old woman with hirsutism and normal menstrual cycles. No genital abnormalities were present. Elevated basal serum levels of delta 5-3 beta-hydroxysteroids were demonstrated. Serum pregnenolone (P5) was 3.0 ng/ml, and dehydroepiandrosterone sulphate (DHEA-S) 3245 ng/ml. Basal serum levels of delta 4 steroids were low or within normal limits. Serum progesterone (P) was 0.5 ng/ml, 17 alpha-hydroxyprogesterone (17-OHP) 0.2 ng/ml, androstenedione (delta 4A) 0.4 ng/ml, and testosterone (T) 0.1 ng/ml. All delta 5/delta 4 steroid ratios were elevated. Dexamethasone (DEX) administration normalized the elevated levels of delta 5-3 beta-hydroxysteroids, whereas delta 4-3-ketometabolites exhibited only minor modifications. The DHEA-S/delta 4A ratio increased more than five times over the basal ratio, and P5/P and 17 alpha-hydroxypregnenolone (17-OHP5)/17-OHP ratios did not increase after adrenocorticotrophic hormone ACTH stimulation. Studies of basal ovarian function revealed 17 beta-estradiol (E2) and gonadotropins within normal limits according to the menstrual cycle. In the follicular phase, follicle-stimulating hormone (FSH) was 101.3 ng/ml, luteinizing hormone (LH) 46.0 ng/ml, and E2 49.7 pg/ml; in the luteal phase, FSH was 180.0 ng/ml, LH 69.3 ng/ml, and E2 50.1 pg/ml. The presence of ovulatory cycles was documented on the basis of the biphasic pattern of the basal body temperature cycles and the increment in P levels. This case demonstrates the existence of normal ovulatory function in a woman with late-onset of a mild form of HSD.

3-Hydroxysteroid Dehydrogenases↗

Differential diagnosis of CT-hypodense cranial lesions with indium-111-oxine-labeled leukocytes.

Scintigraphy using indium-111-oxine-labeled white blood cells was used as a complementary diagnostic study in the differential diagnosis of 20 intracerebral cystic lesions for which computerized tomography scanning did not exclude abscess. To lower the rate of false-positive findings with scintiscanning, three criteria of positivity were tested in the 20 lesions. The most stringent criterion yielded 100% sensitivity, 94% specificity, and 96% diagnostic accuracy. The clinical and surgical implications of these results are discussed.

Adult↗

[Epidemiology of human hydatidosis in the Province of Río Negro, Argentina].

The number of human cases with hydatidosis in the Province de Río Negro in the period 1969-1983 was determined by a retrospective exam of the registers at the Provincial Ministry of Health. From 1216 cases the yearly numbers between 59.4 in 1969-78 and 124.4 cases between 1979-83. This implies a yearly of 3.24 X 10,000 and with the most frequent localization in the liver. The average days of hospitalization was 29.2 per patient. The highest correspond to the southern departments of the Province 6.57 X 10,000 in the 40 Sanitary Zone. Eighty two and thirty five per cent of the cases had immunological confirmation with DD5, before surgery. The census allowed us to determine that rates of prevalence were in school children 1.09%, in conscripts, 0.28% and in adult settlers 2.58%. The average of positive serological cases in the province, was 0.77%. The yearly number of cases diagnoses is estimated in 4% of the existent carriers and is the highest in the world. The followup and control of children who had surgery, allowed us to detect that 30% of the cases presented new hydatid cyst before the 5 year lapse. Different factors put Río Negro with the highest rates of denounced human hydatidosis. These are related to living conditions around cattle farms and the socio economics and educational factors, which are analyzed in this paper. Modifications in the Programme for the control of hydatidosis has been put into action by the sanitary authorities.

Adult↗

Endocrine and immunogenetic evaluation of an XX male infant with perineoscrotal hypospadias.

To clarify the origin of the genital ambiguity occasionally associated with the XX male syndrome, a series of endocrinological studies were undertaken in an affected 6 months old infant with perineoscrotal hypospadias. The patient fulfilled all the diagnostic criteria of the syndrome: the testes were descended bilaterally, the Mullerian derivatives were absent, the 46,XX chromosome complement was ascertained in different cell lines, and male levels of H-Y antigen were detected in cultured skin fibroblasts. Circulating gonadotrophin levels and pituitary LRH responsiveness were within normal limits for the age group. Serum testosterone (T) levels were normal, and gonadal stimulation with hCG caused a significant rise on serum T. Incubations of [3H]T with fibroblasts from genital skin revealed normal activity of steroid 5 alpha-reductase. Moreover, normal concentrations of thermostable cytosol androgen receptors were revealed in cultured fibroblasts. Altogether the results indicated that ambiguity of the external genitalia in this patient was the result of neither abnormal T biosynthesis, peripheral A-ring T reduction, nor androgen intracellular specific binding, and suggested that the nature of the incomplete virilization could be a non-endocrine independent event associated to this disorder. The data are also consistent with the notion that testicular impairment observed in adult XX males develops later in life.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Cystic cavernous angiomas of the posterior fossa. Report of three cases.

Three histologically verified cases of cystic cavernous angioma of the posterior fossa are reported. The clinical history of these patients is presented, and the diagnostic and surgical problems arising from the extreme rarity of the combination of cerebellar site and cystic nature of the lesion are discussed.

Adult↗

[Contribution of immunology to the differentiation of arteritis in young persons. Apropos of 2 cases].

The authors report two observations of T.A.O. placed under the heading of "Systems Affections" after the discovery of immunologic abnormalities. Vascular troubles in L.E.A.D. and generalised sclerodermis are, apart from the Raynaud Syndrom, exceptional. They oriente specially towards a T.A.O., and in absence of caracteristic symptoms, they retard the diagnosis of a connective. The reader is reminded of the characteristics of the "Buerger Affection" which must no longer be considered as unique anatomoclinic entity, due to modern immunologic and phlebologic exams.

Adult↗

[Study of the muscular perfusion of the lower limbs using thallium 201 scintigraphy before and after lumbar sympathectomy in 13 patients].

Scintigraphy with 201-Thallium is a useful method for exploring muscle circulation in lower limbs of patients with arteritis. Comparative values with time can be obtained by studying respective isotopic activity ratios of the thigh, calf and foot. Unilateral isolated lumbar sympathectomy was performed in 13 patients for arteriopathy of the lower limbs (7 claudications, 4 isolated trophic disorders, 1 thrash-foot and 1 juvenile arteriopathy). Investigations included clinical and arteriographic explorations and functional tests (Doppler, distal pressure, digital plethysmography and 201-Thallium muscle scintigraphy) before and after operation. Pathology of the sympathetic chain was determined in each case. Short-term (2 weeks) follow up examinations gave data showing absence of correlation between the operative procedure and scintigraphy results. Muscle perfusion was improved in only 3 cases: one presented paradoxical improvement contralateral to the sympathectomy, while no change from the pre-operative values was recorded in 9 patients. The findings raise questions concerning the reproducibility of the scintigraphic method, and also confirm the pathogenic hypothesis by which lumbar sympathectomy has only a limited effect on muscle circulation.

Arteriosclerosis↗

Omental evisceration through an abdominal stab wound: is exploratory laparotomy mandatory?

The authors reviewed and analysed the records of 75 patients with omental and bowel evisceration as a result of abdominal stab wounds to discover whether omental prolapse makes laparotomy mandatory. Major intraabdominal injuries were found in 82.7% of the total group, 82.9% in those with omental protrusion and 82.5% in patients with bowel prolapse. The nature of the injuries and the incidence of multiple organ trauma were similar in the two groups. Negative laparotomy did not cause important morbidity. The authors conclude that omental herniation after stab wounds of the abdomen should routinely prompt exploratory celiotomy.

Abdominal Injuries↗

Right ventricular function in Chagas disease.

To study right ventricular function, we performed cardiac catheterization, and right and left cineventriculograms in 60 chagasic patients and 15 non-chagasic, non-heart disease patients. Chagasic patients with normal electrocardiograms and left cineventriculograms also had normal right ventricular function. Nine of 14 chagasic patients with normal Ecg's and early left ventricular damage had right ventricular dilatation and/or segmental inferior-apical asynergy. Fourteen of 19 chagasic patients with abnormal Ecg's and advanced left ventricular damage, but without signs of congestive heart failure, and all chagasic patients with congestive heart failure, had marked right ventricular dilatation, severe right contractility depression and abnormal right apical or para-apical motion. These findings indicate that Chagas disease is a diffuse cardiomyopathy in which the left ventricle seems to be affected earlier and to a greater extent than the right ventricle. Since segmental abnormalities were predominantly observed in apical and para-apical areas of the ventricles, performance of right and left cineventriculograms is recommended before implantation of cardiac pacemakers.

Adult↗

[Hepatopathy associated with ulcerative colitis in childhood. Apropos of 2 cases].

Two patients of 3 and 5 years old presented ulcerative colitis associated with liver disease. In both cases, liver biopsy evidenced a severe pericholangitis. The authors have undertaken a comparative bibliographical study, emphasizing the low incidence of this association in our environment. They have also studied the relationship between the hepatic lesion and that of the colonic mucosa.

Child, Preschool↗

46,XX gonadal absence: a variant of the XX pure gonadal dysgenesis?

Two unrelated 46,XX individuals with female phenotype and sexual infantilism were studied. Endocrine findings showed anoestrogenism and hypergonadotrophism with a normal pituitary response to LRH. Laparotomy disclosed ovarian absence with normal Mullerian derivatives and no gonadal streaks were found within the true pelvis or inguinal canals. This condition represents the 46,XX counterpart of the 46,XY gonadal absence syndrome. Whether the XX agonadism reported here is a different and distinctive entity or is a variant of the XX pure gonadal dysgenesis syndrome can not be ascertained at present.

Adult↗

Clinical and endocrine spectrum in patients with the 45,X/46,XY karyotype.

Cytogenetic and endocrine studies were performed in five unrelated 45,X/46,XY individuals in an attempt to correlate them with their clinical expression and gonadal morphology. A lack of a consistent pattern between cytogenetic findings and phenotype was observed. Endocrine studies revealed a wide spectrum of hypothalamic, pituitary, and gonadal hormone production as assessed by the base line levels of LH, FSH, T, and delta 4-A and their responses to appropriate exogenous stimulation (LH-RH and HCG). An adequate correlation between endocrine findings with gonadal morphology and phenotype could be established; thus demonstrating that patients with this particular chromosome complement have a functional integrity of the gonadotropin hypothalamic pituitary activity modulated accordingly with the gonadal function of each particular case.

Adolescent↗

Hospital-based employees' opinions about adolescents of four racial-ethnic groups.

We obtained opinions about adolescents' characteristics and behaviors from 290 employees of a medical school and its hospitals. Employees were asked for their opinions about 4 positive, 2 neutral, and 6 negative characteristics and about 5 sexual, 8 substance use, and 5 relationship behaviors. Most employees were willing to characterize adolescents in general, but fewer were willing to express opinions about white, black, Mexican-American or Oriental teens in particular. There was poor correspondence between the general adolescent ratings, the ratings of the racial-ethnic groups, and reports in the literature. The respondents, unable to accurately describe white and black teens, could not characterize Mexican-American teens and characterized Oriental teens predominantly in the category "least likely to behave this way." The data suggest that adults' stereotyping of adolescents' behaviors and characteristics is common and suggests the need for programs to better inform adults about adolescents.

Adolescent↗

Induction of ovulation in a true hermaphrodite with male phenotype.

Ovulation was induced in a 16-yr-old 46 XX/47 XXY true hermaphrodite with a male phenotype. The presence of testicular tissue was assessed by a normal androgen response to hCG. Administration of FSH and LH for 8 consecutive days, followed by a single dose of hCG, induced a biphasic serum profile of 17 beta-estradiol and progesterone similar to that observed in normal menstrual cycles. In addition, a significant rise in serum testosterone was noticed during the luteal phase. Laparotomy revealed the presence of a uterus, with evidence of endometrial bleeding and absence of a vagina. These results demonstrated that gonadotropins were able to induce follicular maturation, ovulation, and endometrial bleeding in a true hermaphrodite resembling a normal ovulatory cycle. Gonadotropin administration can be used as a diagnostic tool for establishing the presence of ovarian tissue in this gonadal development abnormality.

Adolescent↗

Gonadotropin dynamics in XX males.

Hypothalamic-pituitary gonadotropin function was evaluated in two postpubertal XX males. Serum levels of LH and FSH were moderately elevated, and the serum testosterone level was low. A subnormal response by testicular Leydig cells to hCG was observed. The LH and FSH responses to LRH were normal. A significant LH increase was observed after castration. Weekly administration of testosterone enanthate (250 mg) for 10 consecutive weeks caused a reduction (greater than 75%) in gonadotropins and abolishment of the LRH pituitary response. No differences were observed in terms of gonadotropin dynamics compared with other forms of hypergonadotropic hypogonadism. These results indicate that XX males exhibit hypergonadotropic hypogonadism secondary to testicular failure with a preserved androgen responsiveness of the hypothalamic-pituitary unit.

Adult↗