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Objective: identify the morphological characteristics of hypertrophic cardiomyopathy evaluated by cardiac magnetic resonance and analyze the association between them and cardiovascular events. Methodology: an historic cohort study of a Mexican population with hypertrophic cardiomyopathy evaluated by cardiac magnetic resonance at Instituto Nacional de Cardiología Ignacio Chávez (Mexico City) from August 2007 through October 2013. Cardiovascular measurements and postgadolinium delayed enhancement evaluations were conducted. An analysis of survival was conducted to predict: syncope, malignant ventricular arrhythmias, implantation of automatic defibrillator, hospitalization due to heart failure, and death from any cause during a 36-month follow-up period. Results: 124 patients with ages of 40.1 ±21.9 years, 55% men, were included. The population presented a median of 5 hypertrophic segments per patient with maximum thickness of 24.3 ± 6.8 mm. Delayed enhancement was observed in 85% of the patients and 35% presented obstruction of the left ventricular outflow tract; the former proved better for predicting event-free survival. There was a direct correlation between the number of segments with delayed enhancement and myocardial mass (p < 0.05), maximum ventricular wall thickness (p < 0.05) and number of hypertrophic segments (p < 0.05), but not with the left ventricular ejection fraction. Conclusion: delayed enhancement indicates a tendency to adverse events, which is not observed with traditional factors such as degree of obstruction of the left ventricular outflow tract and family history of sudden death. The extent of delayed enhancement is correlated with ventricular thickness and mass. [ABSTRACT FROM AUTHOR]

The separation of nickel and cobalt from ammoniacal solutions in Caron's Process has been performed using solvent extraction with the active extractant 2-hydroxy-5-nonylacetophenone oxime in the commercial product LIX® 84-I from Henkel Corporation. The influence of ammonia concentration of the initial feed and the nature of the diluent on the loaded capacity of nickel and ammonia of the organic phase has been analyzed. The mass transfer of the metal, from the organic phase to aqueous phase, is enhanced with the increase of the temperature; stripping tests were carried out with spend nickel electrolyte. Two stages of extraction, one scrubbing and two stages of stripping are recommended for LIX 84-I at the studied temperature, in these conditions there are two streams with Ni/Co ratio of the 0,009/1 (rafinate) and 6500/1 (pregnant electrolyte) that have good quality to obtain the metals for the established path. [ABSTRACT FROM AUTHOR]

Nucleotides in the intestinal lumen may decrease the inflammatory response to ischemia-reperfusion. In a newborn-swine model, we showed that perfusion of the intestinal lumen with nucleotides in concentrations similar to those in human milk induced hyperemia. The levels of hypoxanthine (and xanthine) were not increased in the presence of nucleotides during ischemia-reperfusion, and the number of leukocytes accumulated in the intestine was reduced in the presence of nucleotides. Furthermore, nucleotides may have decreased protein leak and the production of nitric oxide during ischemia. These effects are not changed significantly in the presence of an adenosine antagonist. We interpreted our results to indicate that the protective effects of nucleotides in the intestinal lumen are not due to adenosine alone. [ABSTRACT FROM AUTHOR]

Abstract Background Increased risk of schizophrenia in adolescent males indicates that a link between the development of dopamine-related psychopathology and testosterone-driven brain changes may exist. However, contradictions as to whether testosterone increases or decreases dopamine neurotransmission are found and most studies address this in adult animals. Testosterone-dependent actions in neurons are direct via activation of androgen receptors (AR) or indirect by conversion to 17β-estradiol and activation of estrogen receptors (ER). How midbrain dopamine neurons respond to sex steroids depends on the presence of sex steroid receptor(s) and the level of steroid conversion enzymes (aromatase and 5α-reductase). We investigated whether gonadectomy and sex steroid replacement could influence dopamine levels by changing tyrosine hydroxylase (TH) protein and mRNA and/or dopamine breakdown enzyme mRNA levels [catechol-O-methyl transferase (COMT) and monoamine oxygenase (MAO) A and B] in the adolescent male rat substantia nigra. We hypothesized that adolescent testosterone would regulate sex steroid signaling through regulation of ER and AR mRNAs and through modulation of aromatase and 5α-reductase mRNA levels. Results We find ERα and AR in midbrain dopamine neurons in adolescent male rats, indicating that dopamine neurons are poised to respond to circulating sex steroids. We report that androgens (T and DHT) increase TH protein and increase COMT, MAOA and MAOB mRNAs in the adolescent male rat substantia nigra. We report that all three sex steroids increase AR mRNA. Differential action on ER pathways, with ERα mRNA down-regulation and ERβ mRNA up-regulation by testosterone was found. 5α reductase-1 mRNA was increased by AR activation, and aromatase mRNA was decreased by gonadectomy. Conclusions We conclude that increased testosterone at adolescence can shift the balance of sex steroid signaling to favor androgenic responses through promoting conversion of T to DHT and increasing AR mRNA. Further, testosterone may increase local dopamine synthesis and metabolism, thereby changing dopamine regulation within the substantia nigra. We show that testosterone action through both AR and ERs modulates synthesis of sex steroid receptor by altering AR and ER mRNA levels in normal adolescent male substantia nigra. Increased sex steroids in the brain at adolescence may alter substantia nigra dopamine pathways, increasing vulnerability for the development of psychopathology.