Depression: a predictor of smoking relapse in a 6-month follow-up after hospitalization for acute coronary syndrome

Objective The objective of the study was to investigate whether depression is a predictor of postdischarge smoking relapse among patients hospitalized for myocardial infarction (MI) or unstable angina (ILIA), in a smoke-free hospital. Methods Current smokers with MI or UA were interviewed while hospitalized; patients classified with major depression (MD) or no humor disorder were reinterviewed 6 months post discharge to ascertain smoking status. Potential predictors of relapse (depression; stress; anxiety; heart disease risk perception; coffee and alcohol consumption; sociodemographic, clinical, and smoking habit characteristics) were compared between those with MD (n = 268) and no humor disorder (n = 135). Results Relapsers (40.4%) were more frequently and more severely depressed, had higher anxiety and lower self-efficacy scale scores, diagnosis of UA, shorter hospitalizations, started smoking younger, made fewer attempts to quit, had a consort less often, and were more frequently at the `precontemplation` stage of change. Multivariate analysis showed relapse-positive predictors to be MD [odds ratio (OR): 2.549; 95% confidence interval (CI): 1.519-4.275] (P<0.001); `precontemplation` stage of change (OR: 7.798; 95% CI: 2.442-24.898) (P<0.001); previous coronary bypass graft surgery (OR: 4.062; 95% CI: 1.356-12.169) (P=0.012); and previous anxiolytic use (OR: 2.365; 95% CI: 1.095-5.107) (P=0.028). Negative predictors were diagnosis of MI (OR: 0.575; 95% CI: 0.361-0.916) (P=0.019); duration of hospitalization (OR: 0.935; 95% CI: 0.898-0.973) (P=0.001); smoking onset age (OR: 0.952; 95% CI: 0.910-0.994) (P=0.028); number of attempts to quit smoking (OR: 0.808; 95% CI: 0.678-0.964) (P=0.018); and `action` stage of change (OR: 0.065; 95% CI: 0.008-0.532) (P= 0.010). Conclusion Depression, no motivation, shorter hospitalization, and severity of illness contributed to postdischarge resumption of smoking by patients with acute coronary syndrome, who underwent hospital-initiated smoking cessation.

Screening of autosomal gene deletions in patients with hypogonadotropic hypogonadism using multiplex ligation-dependent probe amplification: detection of a hemizygosis for the fibroblast growth factor receptor 1

P>Objective Congenital hypogonadotropic hypogonadism with anosmia (Kallmann syndrome) or with normal sense of smell is a heterogeneous genetic disorder caused by defects in the synthesis, secretion and action of gonadotrophin-releasing hormone (GnRH). Mutations involving autosomal genes have been identified in approximately 30% of all cases of hypogonadotropic hypogonadism. However, most studies that screened patients with hypogonadotropic hypogonadism for gene mutations did not include gene dosage methodologies. Therefore, it remains to be determined whether patients without detected point mutation carried a heterozygous deletion of one or more exons. Measurements We used the multiplex ligation-dependent probe amplification (MLPA) assay to evaluate the potential contribution of heterozygous deletions of FGFR1, GnRH1, GnRHR, GPR54 and NELF genes in the aetiology of GnRH deficiency. Patients We studied a mutation-negative cohort of 135 patients, 80 with Kallmann syndrome and 55 with normosmic hypogonadotropic hypogonadism. Results One large heterozygous deletion involving all FGFR1 exons was identified in a female patient with sporadic normosmic hypogonadotropic hypogonadism and mild dimorphisms as ogival palate and cavus foot. FGFR1 hemizygosity was confirmed by gene dosage with comparative multiplex and real-time PCRs. Conclusions FGFR1 or other autosomal gene deletion is a possible but very rare event and does not account for a significant number of sporadic or inherited cases of isolated GnRH deficiency.

Insulin modulates norepinephrine-mediated melatonin synthesis in cultured rat pineal gland

The mammalian pineal gland synthesizes melatonin in a circadian manner, peaking during the dark phase. This synthesis is primarily regulated by sympathetic innervations via noradrenergic fibers, but is also modulated by many peptidergic and hormonal systems. A growing number of studies reveal a complex role for melatonin in influencing various physiological processes, including modulation of insulin secretion and action. In contrast, a role for insulin as a modulator of mclatonin synthesis has not been investigated previously. The aim of the current study was to determine whether insulin modulates norepinephrine (NE)-mediated melatonin synthesis. The results demonstrate that insulin (10(-8)M) potentiated norepinephrine-mediated melatonin synthesis and tryptophan hydroxylase (TPOH) activity in ex vivo incubated pineal glands. When ex vivo incubated pineal glands were synchronized (12h NE-stimulation, followed by 12h incubation in the absence of NE), insulin potentiated NE-mediated melatonin synthesis and arylalkylamine-N-acetyltransferase (AANAT) activity. Insulin did not affect the activity of hydroxyindole-O-methyltranferase (HIOMT), nor the gene expression of tpoh, aanat, or hiomt, under any of the conditions investigated. We conclude that insulin potentiates NE-mediated melatonin synthesis in cultured rat pineal gland, potentially through post-transcriptional events. (C) 2007 Elsevier Inc. All rights reserved.

Influence of fixed electric charges on potential profile across the squid axon membrane

The potential profile for a model of squid axon membrane has been determined for two physiological states: resting and action states. The non-linear Poisson-Boltzmann equation has been solved by considering the volumetric charge densities due to charges dissolved in an electrolytic solution and fixed on both glycocalyx and cytoplasmatic proteins. Results showing the features of the potential profile along the outer electrolytic region are similar for both resting and action states. However, the potential fall along glycocalyx at action state is lower than at resting. A small variation in the Na+ concentration drastically affects the surface membrane potentials and vice versa. We conclude that effects on the potential profile due to surface lipidic bilayer charge and contiguous electric double layers are more relevant than those provoked by fixed charges distributed along the cell cytoplasm. (c) 2007 Elsevier B.V. All rights reserved.