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J M Torres

Publications and source records attributed to J M Torres.

107 records · Page 6Linked to original sources
PubMedDate not supplied

Evidence of different actions of testosterone, estradiol, FSH, and LH on the growth axis.

To study the possible role of sexual hormones, Testosterone (T), Estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) on the growth axis, we examined the correlations between the sex, growth hormone (GH), insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein 3 (IGFBP3), FSH, LH, T and E2, in growth retarded children ranging in age from 7 to 13 yr. All hormones were measured by Radioimmunoassay (RIA) in a pool of aliquots of samples obtained every 20 min over 12 h (overnight) in each child. Multivariate statistical analysis was performed. We have found: a) Thai only FSH concentrations were significantly higher in girls than in boys; b) A positive correlation between T-IGF-1; T-IGFBP3; FSH-LH; FSH-IGF-1; FSH-IGFBP3, LH-IGF-1, LH-IGFBP3 the sex-FSH; and the sex-IGFBP3 c) A high positive correlation between plasmatic E2 and IGF-1/IGFBP3 ratio (an index of free, active IGF-1). We concluded that the sex, FSH, LH, T and E2 influence the growth axis. The sex through IGFBP3; LH, FSH, and T through IGF1 and IGFBP3; E2 through the IGF-1/IGFBP3 ratio, an index of active IGF-1.

Adolescent↗
PubMedDate not supplied

Crystalline dihydrotestosterone implants in the lateral septum of male rats. A positive effect on LH and FSH.

Previous investigations in our laboratory have shown that testosterone implanted into the lateral septum in male rats increases LH and FSH secretion. However, it was unclear whether the effect of testosterone was direct via androgen receptor, or indirect via the estrogen receptor after conversion by aromatization to estradiol. To answer this question, we implanted either testosterone or the non-aromatizable androgen 5 alpha-dihydrotestosterone (DHT), into the lateral septum of adult male rats and measured plasma levels of LH and FSH by radioimmunoassay 2 days after implantation. Both testosterone and DHT significantly increased the plasma LH and FSH concentrations. Mean concentration of LH in control animals was 0.21 +/- 0.06 ng/ml, a figure that increased to 0.7 +/- 0.12 and 0.55 +/- 0.1 ng/ml after DHT or testosterone implantation respectively. Mean concentration of FSH in control animals was 1.5 +/- 0.3 ng/ml; this figure increased to 3 +/- 0.3 and 2.9 +/- 0.3 ng/ml after DHT or testosterone implantation. Neither plasma DHT (64.0 +/- 5.6 vs. 52 +/- 5 ng/100ml) nor plasma testosterone levels (4.1 +/- 0.38 vs. 3.3 +/- 0.18 ng/ml) were significantly affected by the implants. We conclude that androgens independently of conversion to estrogen acting in the lateral septum facilitates the release of LH and FSH.

Animals↗
PubMedDate not supplied

Effects of acute alcohol intoxication on pituitary-gonadal axis hormones, pituitary-adrenal axis hormones, beta-endorphin and prolactin in human adults of both sexes.

- The effects of acute alcohol intoxication (AAI) on the pituitary-gonadal axis hormones, and the possible contribution of pituitary-adrenal axis hormones, beta-endorphin and prolactin to alcohol-induced dysfunction of pituitary-gonadal axis hormones were studied in adult men and women. Blood samples were drawn from adults of both sexes who arrived at the emergency department with evident behavioural symptoms of drunkenness (AAI) or from adult volunteers with nil consumption of alcohol (controls). Our results demonstrated that AAI produces a high increase in plasma prolactin, corticotropin (adrenocorticotropic hormone, ACTH), and cortisol in adults of both sexes, a decrease in luteinizing hormone levels only in men, an increase in dehydroepiandrosterone-sulphate (DHEAS) and a contradictory behaviour of testosterone according to gender, with increased plasma testosterone in women and a decrease in men. ACTH and prolactin correlated positively with cortisol, DHEAS and testosterone in women, which suggests that prolactin and ACTH could contribute to stimulated adrenal androgen production. In contrast, the decrease in testosterone and increase in beta-endorphin in men suggests that AAI could have an inhibitory effect on testicular testosterone, perhaps mediated by beta-endorphin. Our results suggest that the effect of alcohol on pituitary-gonadal axis hormones in humans could depend on the gender and degree of sexual maturity of the individual.

Acute Disease↗
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Diagnostic value of serum antibody and antigen detection in heroin addicts with systemic candidiasis.

The diagnostic value of antibody detection by indirect hemagglutination (IHA), indirect immunofluorescence (IFA), and counterimmunoelectrophoresis (CIE) and of Candida albicans mannan antigen detection by latex agglutination was studied in 36 cases of systemic candidiasis in heroin addicts. The IHA and IFA techniques were highly sensitive (97% and 91%, respectively), but their specificity was low (60% and 50%). When a titer of greater than or equal to 1:2,560 was used as a criterion for IHA positivity, the specificity of the test rose to 87%, with sensitivity at 75%. CIE had a high degree of specificity (96%) but a low degree of sensitivity (58%). A good correlation was found between clinical evolution of infection and serologic data. Two of 12 patients who could be followed for 9-16 months had a rise in antibody titer detected either by IFA or by IHA and CIE. These two patients had a persistent chondrocostal tumor and C. albicans endocarditis, respectively. All of the other patients, who were cured, had a decrease in titer detected by IHA and IFA and had negative CIE results at the end of follow-up. Serum mannan antigen was not found in any case. The detection of antibody to C. albicans may be useful for diagnosis and follow-up of such patients.

Adult↗
PubMedDate not supplied

Imported histoplasmosis in Spain.

Histoplasma capsulatum is a dimorphic fungus endemic in the American continent but not in Europe, where cases are usually imported. Its favorite habitat is in warm humid soils. Guano from birds and bats enhance the sporulation of the mycelial phase.1 Man acquires H. capsulatum through inhalation of spores. Most people infected by this fungi remain asymptomatic, but around 10-50% can start an illness ranging from acute pulmonary histoplasmosis to chronic histoplasmosis. In both, there is close clinical resemblance to pulmonary tuberculosis. Immunodepressed patients undergo a more severe form of the disease, usually presenting in the acute disseminated form. We present seven immunocompetent patients with histoplasmosis acquired after traveling to several American countries.

Histoplasmosis↗
PubMedDate not supplied

[Transmissible spongiform encephalopathies in animals].

INTRODUCTION: The transmissible spongiform encephalopathies affect several species of higher animals apart from man. Amongst these, undoubtedly the best known is that affecting cattle, since the association between consumption of beef and its derivatives and the appearance of a variant of Creutzfeldt-Jakob disease in humans has been established. DEVELOPMENT: This type of pathology has been well known for many years in the ovine family, particularly in sheep and goats. In spite of the establishment of hypotheses linking the cause of the appearance of spongiform encephalopathy in cows with an interspecies jump of the disease between the ovine and bovine families, this has not yet been proved. Concomitant with the epidemic of bovine spongiform encephalopathy, other species of animals were reported to have been affected by an identical disease. These included farmed mink, deer, elks, cats and two species of exotic African ungulates (the nyala and the greater kudu). All cases were described in animals kept in captivity for human consumption. Thus it would seem that there was a common cause of the disease in all cases. CONCLUSION: In this paper we describe the most relevant aspects of the appearance of this disorder in animals, including the symptoms, epidemiology and pathology typical of each specific condition.

Animals↗
PubMedDate not supplied

[Correlation between intradermal reaction and immunoelectrophoresis in human hydatidosis].

The results obtained by the immunoelectrophoresis (IEP) aand Casoni intradermal (IDR) tests in a group of 50 hydatidosis patients in which the presence of cysts was later confirmed at surgery, are analyzed. The sensitivity of the IEP test was 74%; the IDR test was positive in 54% of these patients and there was no correlation between the results of the two tests in 24% of the cases. The low sensitivity observed for the IDR test, its known nonspecificity and its poor correlation with IEP test results do not enable us to recommend its use for the diagnosis of hydatid disease or for the selection of cases in which an immunodiagnostic confirmation is feasible. This recommendation would be possible if appropriate antigens regarding specificity and reactivity were available, and could be employed with standardized methods to read and evaluate cutaneous reactivity.

Echinococcosis↗
PubMedDate not supplied

[Involvement of the immunological system in the pathogenesis of transmissible spongiform encephalopathies].

OBJECTIVE: We review the current knowledge relative to the role of different immune system components and their contribution the spread of prions throughout the infected organism. DEVELOPMENT: During the last years research made on transmissible spongiform encephalopathies conducted to the assumption that changes in the structure of a determined protein (prion protein, PrP) may become self-propagative. The generally assumed finding of an abnormally folded protein as the causative agent, able to propagate in hosts different from it was originated, is changing our views of transmissible diseases. The concept of infection resulting from pathogen propagation within a susceptible host has been steadily linked to the ability of nucleic acids to replicate their own coded information. In the prionosis, term comprising all known prion disorders, the information seems to be coded within the own protein conformation. This phenomena, once again, challenges the well-established principles of molecular biology. CONCLUSIONS: Propagation of prions uses strategies not previously recognized, and depends upon prion conformation and/or specific host restrictions. Thus, certain sheep and goat prion strains (scrapie) or human (variant of Creutzfeldt-Jakob disease) invade the brain after an initial interaction with the immune system of affected individuals. The involvement of the lymphoreticular system or, at least, certain host's immune competence seems to be a prerequisite for neuro-invasion after a natural infection or peripheral inoculation. On the other hand, proper identification of immune cell types involved may open the possibility for post exposure prophylaxis.

Animals↗
PubMedDate not supplied

[Characterization of exoantigens of Aspergillus fumigatus. Study of factors influencing their quality].

Several methods are available for exoantigen preparation and standardization, but until now there is no agreement about which is the best of them. Moreover an exhaustive analysis of the influence of several experimental conditions on the antigenic composition of exoantigens of Aspergillus fumigatus is badly needed. In this paper the analysis of the influence of the following conditions on this antigenic composition is described (origin of strains, culture media composition, incubation time of mycelial stationary growth in culture media and immunological techniques used to standardize the antigens. Antigenic extracts were obtained from six strains of A. fumigatus from different origin (pathogenic, collection and contaminants) growing in different broth culture media (glucose-asparagine, Sabouraud, dialyzed neopeptone, and Czapek Dox). The culture media were separated from mycelium, dialyzed and freeze-dried. These extracts were used at concentrations of 100 mg/ml. Immunoprecipitation techniques (immunodiffusion, immunoelectrophoresis and crossed-immunoelectrophoresis) were used in this work to evaluate the quality of the extracts. All these methods were performed with human sera from patients with aspergilloma and animal sera (rabbit and goat) experimentally immunized. Averages and standard deviations were calculated for each group and the possible significance of differences between groups was studied using the Student-t test. Analysis of results shows that immunological characteristics of the exoantigens used for diagnosis are independent of the different incubation times studied. It has been confirmed in this study that results depend to a certain degree on the origin of the serum used. The strains kept in collection for several years showed less reactivity than those recently isolated.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

[Reactivity of a purified antigen of Paracoccidioides brasiliensis with paracoccidioidomycosis and histoplasmosis sera].

The immunoelectrophoretic reactivity of a "crude" and a "purified" antigens of Paracoccidiodes brasiliensis against the sera of confirmed cases of paracoccidioidomycosis and histoplasmosis was evaluated. The "crude" antigen revealed precipitating antibodies in both the homologous and the heterologous human sera; the number of precipitating systems being higher with the former. The "purified" antigen reacted only with the homologous sera. It is postulated that the use of such "purified" antigen may significantly reduce the non specificity of the serologic tests in the immunodiagnosis of paracoccidioidomycosis.

Antigen-Antibody Reactions↗
PubMedDate not supplied

[Letter on abortion].

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Abortion, Induced↗