Exercise training associated with estrogen therapy induced cardiovascular benefits after ovarian hormones deprivation

Menopause is recognized as a period of increased risk for coronary heart disease. Although the benefits of exercise training in lowering cardiovascular risk factors are well established, the risks and benefits of hormone therapy have been questioned. The purpose of the present study was to investigate the effects of estrogen therapy (HT) associated or not with exercise training (ET) in autonomic cardiovascular control in ovariectomized (OVX) rats. Female rats were divided into: control, OVX, OVX+HT, OVX+ET and OVX+HT+ET. HT was performed using a 0.25 mg 8-weeks sustained release pellet. Trained groups were submitted to an 8-week exercise training protocol on treadmill. Baroreflex sensitivity (BRS) was evaluated by heart rate responses to arterial pressure (AP) changes, and vagal and sympathetic tonus by pharmacological blockade. Ovariectomy induced an AP increase (123 +/- 2 mmHg vs. 108 +/- 2 mmHg), BRS impairment (similar to 69%), sympathetic activation (similar to 100%) and vagal tonus reduction (similar to 77%) compared to controls. HT or ET normalized the changes in parasympathetic tonus. However, only the association HT + ET was able to promote normalization of AP, BRS and sympathetic tonus, as compared to controls. These results indicate that ET induces cardiovascular and autonomic benefits in OVX rats under HT, suggesting a positive role of this association in the management of cardiovascular risk factor in postmenopausal women. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Role of thyroid hormones and their receptors in peripheral nerve regeneration.

After peripheral nerve injury in adult mammals, reestablishment of functional connections depends on several parameters including neurotrophic factors, the extracellular matrix, and hormones. However, little is known about the contribution of hormones to peripheral nerve regeneration. Thyroid hormones, which are required for the development and maturation of the central nervous system, are also important for the development of peripheral nerves. The action of triiodothyronine (T3) on responsive cells is mediated through nuclear thyroid hormone receptors (TRs) which modulate the expression of specific genes in target cells. Thus, to study the effect of T3, it is first necessary to know whether the target tissues possess TRs. The fact that sciatic nerve cells possess functional TRs suggests that these cells can respond to T3 and, as a consequence, that thyroid hormone may be involved in peripheral nerve regeneration. The silicone nerve guide model provides an excellent system to study the action of local administration of T3. Evidence from such studies demonstrate that animals treated locally with T3 at the level of transection have more complete regeneration of sciatic nerve and better functional recovery. Among the possible regulatory mechanisms by which T3 enhances peripheral nerve regeneration is rapid action on both axotomized neurons and Schwann cells which, in turn, produce a lasting and stimulatory effect on peripheral nerve regeneration. It is probable that T3 up- or down-regulates gene expression of one or more growth factors, extracellular matrix, or cell adhesion molecules, all of which stimulate peripheral nerve regeneration. This could explain the greater effect of T3 on nerve regeneration compared with the effect of any one growth factor or adhesion molecule.

Coloration signals the ability to cope with elevated stress hormones: effects of corticosterone on growth of barn owls are associated with melanism.

Stressful situations during development can shape the phenotype for life by provoking a trade-off between development and survival. Stress hormones, mainly glucocorticoids, play an important orchestrating role in this trade-off. Hence, how stress sensitive an animal is critically determines the phenotype and ultimately fitness. In several species, darker eumelanic individuals are less sensitive to stressful conditions than less eumelanic conspecifics, which may be due to the pleiotropic effects of genes affecting both coloration and physiological traits. We experimentally tested whether the degree of melanin-based coloration is associated with the sensitivity to an endocrine response to stressful situations in the barn owl. We artificially administered the mediator of a hormonal stress response, corticosterone, to nestlings to examine the prediction that corticosterone-induced reduction in growth rate is more pronounced in light eumelanic nestlings than in darker nest mates. To examine whether such an effect may be genetically determined, we swapped hatchlings between randomly chosen pairs of nests. We first showed that corticosterone affects growth and, thus, shapes the phenotype. Second, we found that under corticosterone administration, nestlings with large black spots grew better than nestlings with small black spots. As in the barn owl the expression of eumelanin-based coloration is heritable and not sensitive to environmental conditions, it is therefore a reliable, genetically based sign of the ability to cope with an increase in blood corticosterone level.

Avaluació de variables estàtiques i dinàmiques predictives del risc de reincidència en delinqüents sexuals: estudi d’una mostra dels interns de les presons de Catalunya

Aquest treball presenta un estudi sobre les variables de risc de reincidència d’un grup de 315 delinqüents sexuals. Els subjectes han estat obtinguts del total d’interns que van sortir en llibertat condicional o definitiva de les presons de Catalunya entre 1998 i 2003. La investigació té dues parts. Una primera quantitativa on s’analitza la capacitat predictiva de 18 variables representatives de la carrera delictiva, l’incompliment de les mesures de supervisió a la comunitat, la conflictivitat a la presó, el tractament i les condicions de la condemna. Durant un període de seguiment que va de tres anys i 10 mesos a nou anys i dos mesos s’ha enregistrat la reincidència en delictes sexuals, delictes violents, qualsevol tipus de delicte violent (tant sexual com no sexual) i reincidència general. A la segona part, qualitativa, s’han fet entrevistes semiestructurades a un grup de 14 delinqüents sexuals dels quals nou havien reincidit i cinc estaven en llibertat condicional. Si bé les variables més comunes a la investigació sobre delinqüència general han mostrat relació amb la reincidència general, només tres variables de la carrera delictiva han mostrat relació amb la reincidència sexual. L’estudi qualitatiu ha permès obtenir informació sobre la influència de les variables dinàmiques més importants. A partir de l’anàlisi del procés del delicte es configuren tres perfils de delinqüents sexuals que ja s’havien trobat a altres investigacions. A partir de la informació obtinguda es proposen algunes orientacions pels programes de tractament.

Selected polymorphisms in sex hormone-related genes, circulating sex hormones and risk of endometrial cancer.

BACKGROUND: The role of estrogen and progesterone in the development of endometrial cancer is well documented. Few studies have examined the association of genetic variants in sex hormone-related genes with endometrial cancer risk. METHODS: We conducted a case-control study nested within three cohorts to examine the association of endometrial cancer risk with polymorphisms in hormone-related genes among 391 cases (92% postmenopausal at diagnosis) and 712 individually-matched controls. We also examined the association of these polymorphisms with circulating levels of sex hormones and SHBG in a cross-sectional analysis including 596 healthy postmenopausal women at blood donation (controls from this nested case-control study and from a nested case-control study of breast cancer in one of the three cohorts). RESULTS: Adjusting for endometrial cancer risk factors, the A allele of rs4775936 in CYP19 was significantly associated (OR(per allele)=1.22, 95% CI=1.01-1.47, p(trend)=0.04), while the T allele of rs10046 was marginally associated with increased risk of endometrial cancer (OR(per allele)=1.20, 95% CI=0.99-1.45, p(trend)=0.06). PGR rs1042838 was also marginally associated with risk (OR(per allele)=1.25, 95% CI=0.96-1.61, p(trend)=0.09). No significant association was found for the other polymorphisms, i.e. CYP1B1 rs1800440 and rs1056836, UGT1A1 rs8175347, SHBG rs6259 and ESR1 rs2234693. Rs8175347 was significantly associated with postmenopausal levels of estradiol, free estradiol and estrone and rs6259 with SHBG and estradiol. CONCLUSION: Our findings support an association between genetic variants in CYP19, and possibly PGR, and risk of endometrial cancer.

Antigen-induced pleural eosinophilia is suppressed in diabetic rats: role of corticosteroid hormones

Previous studies have evidenced for the existence of interactive regulatory mechanisms between insulin and steroid hormones in different systems. In this study, we have investigated whether endogenous corticosteroids could be implicated in the hyporeactivity to antigen challenge observed in sensitized diabetic rats. Alloxinated rats showed a long-lasting increase in the blood glucose levels and a reduction in the number of pleural mast cells at 48 and 72 hr, but not at 24 hr after alloxan administration. In parallel, they also showed a significant elevation in the plasma levels of corticosterone together with an increase in the adrenal/body weight ratio. Antigen-evoked eosinophil accumulation appeared significantly reduced in rats pretreated with dexamethasone as well as in those rendered diabetic 72 hr after alloxan. In the same way, naive animals treated with dexamethasone also responded with a significant decrease in the number of pleural mast cells. Interestingly, when sensitized diabetic rats were pretreated with the steroid antagonist RU 38486 a reversion of the reduction in the allergen-induced eosinophil accumulation was noted. We conclude that the down-regulation of the allergic inflammatory response in diabetic rats is close-related to reduction in mast cell numbers and over expression of endogenous corticosteroids.

The lack of effect of insulin on luteinizing hormone pulsatility in healthy male volunteers provides evidence of a sexual dimorphism in the metabolic regulation of reproductive hormones.

BACKGROUND: The activity of the neuroendocrine reproductive axis is closely related to nutritional status. This link is particularly important in healthy women, in whom insulin is a positive signal for the reproductive system. In contrast, very little is known regarding this relation in men. OBJECTIVES: This study was designed to evaluate the effect of insulin on the reproductive axis of young male volunteers and to study the effect of short-term hypercaloric feeding on this modulation. DESIGN: The activity of the neuroendocrine reproductive axis was characterized by the pattern of endogenous luteinizing hormone (LH) secretion on the basis of frequent blood sampling protocols. The effect of insulin was tested by comparing the LH secretion pattern between a baseline study and a hyperinsulinemic euglycemic clamp. These studies were performed first in subjects fed a controlled isocaloric diet for 6 d (calculated as 1.5 times their resting metabolic rate) then in the same subjects fed a controlled hypercaloric diet in which 30% extra calories were provided as fat and fructose (3 g · kg(-1) · d(-1)) before undergoing identical protocols. Serum gonadotropins, sex steroids, glucose, insulin, ghrelin, and leptin concentrations were assessed, and the HOMA-IR was calculated. RESULTS: The LH secretion pattern was not affected by insulin or by hypercaloric feeding. Insulin decreased ghrelin and increased leptin concentrations but had no additional effect of hypercaloric feeding despite significantly lower HOMA-IR indexes. CONCLUSIONS: Our data indicate that neither insulin nor short-term hypercaloric feeding has any effect on the activity of the male reproductive axis. They also further support the association between ghrelin and insulin and glucose metabolism. This trial was registered at clinicaltrials.gov as NCT01058681.

La llibertat vigilada: pena accessòria o mesura de seguretat contra els condemnats per delictes sexuals i delictes de terrorisme

La llibertat vigilada s'incorpora al Codi penal com una mesura de seguretat a imposar a subjectes plenament responsables que hagin estat condemnats per delictes contra la llibertat i indemnitat sexual i per terrorisme, el compliment de la mateixa tindrà lloc una vegada que hagin complert la pena privativa de llibertat

Avaluació i predicció del risc de reincidencia en agressors sexuals

En el marc de la intervenció penitenciària amb agressors sexuals, té una especial rellevància la predicció de risc del seu comportament futur, atenent les greus repercussions que poden arribar a tenir les reincidències, tant per a les possibles víctimes com des de la perspectiva de l’impacte mediàtic i pànic moral que generen. En el context internacional, gran part de l’esforç investigador en aquesta matèria ha anat adreçat a l’estandardització de protocols per avaluar el risc de reincidència d’aquests subjectes i orientar la presa de decisions envers ells i la seva vida fora del règim penitenciari. Un dels instruments més novedosos per a la predicció del risc d’agressió sexual és el Sexual Violence Risc – 20 (SVR-20) desenvolupat per un equip d’investigadors canadencs. El treball que aquí es presenta s’inscriu en el marc de l’aplicació pràctica d’aquests procediments predictius al nostre país. L’objectiu principal és aplicar l’SVR-20, de manera retrospectiva, a una mostra d’agressors sexuals per avaluar la capacitat predictiva d’aquest instrument i, així, poder anticipar la possible reincidència dels subjectes. Per aconseguir aquest objectiu, la puntuació total del SVR-20 ha estat correlacionada amb la reincidència veritable, considerant el tractament com una variable a tenir en compte. La regressió logística ha estat utilitzada per examinar el calibratge del model. Aquesta anàlisi avalua el grau de correspondència entre les probabilitats predites (de reincidència) i la reincidència esdevinguda. L’SVR-20 prediu correctament el 55% dels no-reincidents i el 16% dels reincidents. Podem afirmar que aquest model prediu molt millor la reincidència que la no-reincidència. A més, la predicció millora quan hi incloem la variable de tractament. Aquest estudi és el primer a Catalunya que avalua la validesa predictiva d’un instrument d’avaluació del risc de violència sexual. Futures recerques haurien de centrar-se a estimar un punt de tall per a l’SVR-20 que permeti classificar els subjectes de risc de reincidència dels subjectes segurs.