A symptom-specific analysis of the effect of high-frequency left or low-frequency right transcranial magnetic stimulation over the dorsolateral prefrontal cortex in major depression.

BACKGROUND: We have investigated the efficacy of high-frequency left (HFL) versus low-frequency right (LFR) repetitive transcranial magnetic stimulation (rTMS) in depression, focusing on specific symptoms as possible predictors of outcome for these two different types of stimulation. METHOD: Seventy-four outpatients with a major depressive episode treated with an adequate antidepressant dosage for at least 4 weeks were included in our study and randomly assigned to two different groups: HFL or LFR rTMS. The Hamilton Rating Scale for Depression (HAM-D) items were pooled into 6 factors to evaluate specific symptoms as possible predictors of response. RESULTS: Twenty-one out of 32 patients (65.6%) and 24 out of 42 patients (57.1%) were responders in the HFL and LFR groups, respectively. No significant difference in response rate was observed. Considering the whole sample, we found an inverse correlation between activity and HAM-D score reduction and a significant positive relation between somatic anxiety and outcome. An inverse correlation between psychic anxiety and HAM-D score reduction emerged considering the HFL group. In the LFR group, there was a significant negative relationship between baseline activity and the outcome. CONCLUSION: These findings support the hypothesis that LFR rTMS could be as effective as HFL rTMS and more suitable for patients with a higher anxiety degree, particularly in bipolar patients.

Response to SSRIs and role of the hormonal therapy in post-menopausal depression.

The aim of this study is to prospectively evaluate the antidepressant response to SSRIs in depressed post-menopausal women with or without hormonal therapy (HT), and to analyze the possible influence of basal serum levels of gonadotropins and sexual hormones on the antidepressant response. 170 post-menopausal women with a depressive episode (DSM-IV criteria)--47 on HT and 123 not on HT--started the treatment with an SSRI. Depressive symptoms were assessed at baseline and 7 weeks thereafter by raters blind to treatment regimen. Response rates were 63.2% in the group without HT and 83.7% in the HT group (p=0.013). An inverse correlation emerged between the basal levels of LH and the improvement in HRSD scores (p=0.001) in the group without HT. In conclusion, HT appeared to improve the antidepressant response to SSRIs. Furthermore, in post-menopausal women, LH basal levels may be taken into account as possible predictor of response.

The human hypothalamus: a morpho-functional perspective.

Historical investigation suggests that the role of the hypothalamus as a site of integration for endocrine with autonomic and behavioral responses in man rises from ideas and observations first appearing between the 14th and 18th centuries. Research on human, post-mortem brains and by in vivo magnetic resonance techniques reveal that the functional morphology of the hypothalamus in man is very similar to that in Rodents and Primates. As such, the adult human hypothalamus can be subdivided in three longitudinal zones, representing the source and target of neural informations traveling back and forth the brain stem, thalamus, limbic system, basal ganglia and neocortex. In addition, the human hypothalamus can be further partitioned in three anterior-posterior regions, of which the rostral one exerts a prominent regulation in predictive homeostasis, as opposed to the two caudal ones, primarily involved in reactive homeostasis. Finally, nuclear distribution in the human hypothalamus largely coincides with that in higher Mammals. Nevertheless, it is still unclear how the hypothalamus may give rise to specific homeostatic behaviors like hunger, thirst, reproductive and parental attitude, thermoregulation, aggressive-defensive performance, affective-motivational tone, circadian rhythmicity, sleep-wake cycle and immune regulation. The recent advent of new theories for nervous communication, like volume transmission and neural Darwinism, is progressively enlightening our understanding of the role played by the hypothalamic architecture in homeostatic responses, both in Mammals and man.

Molecular mechanisms for pituitary thyrotroph cell growth.

Neuroendocrine, endocrine and autocrine/paracrine signals contribute to the regulation of basal thyrotroph growth. Thyrotropin-releasing hormone (TRH), somatostatin, thyroid hormone (TH), estrogens (Es) and epidermal growth factor, all may play a role both in normal and tumoral thyrotroph proliferation, acting via either plasma membrane receptors and non-genomic steps or nuclear receptors and gene transcription. Signaling features common to all these ligands are involvement of G protein-coupled receptors, mitogen-activated protein kinase cascade and nuclear polyphosphoinositide cycle. In addition, each growth information, independently from the eliciting factor, may be routed intracellularly following a branched pathway, that often links different transduction systems at common check-points, as the Shc-Grb2-SOS complex. Finally, some ligands (e.g. TRH, TH, Es) may display opposite effects on thyrotroph growth, depending on environmental conditions and state of cell differentiation. These ambiguities of response can be interpreted using a "fuzzy" logic-based model of intracellular signaling. Accordingly, check-points common to different transduction cascades may be envisaged as targets for antitumoral therapy selective to the neoplastic thyrotroph cell.

New paradigms in neuroendocrinology: relationships between obesity, systemic inflammation and the neuroendocrine system.

Obesity may be an independent risk factor for coronary artery disease and contribute to a chronic state of systemic inflammation leading to atherosclerosis and metabolic abnormalities, such as diabetes, insulin resistance, dyslipidemia and hypertension. Visceral fat, in fact, may act as an endocrine organ, synthesizing and releasing atherogenic inflammatory cytokines, whose circulating levels depend on the individual's nutritional state, and the extent and anatomical location of fat stores. Unsuspected viral infections might also be involved in enhancing autocrine/paracrine mechanisms of cytokine release from omental fat. Elevated levels of blood cytokines may interact with the neuroendocrine system, autonomic nerves and peripheral lymphatic organs. This may lead to local inflammatory reactions in many body compartments, in particular in the heart tissue, possibly affecting the process of circulatory recovery in obese subjects, and predisposing these patients to a greater risk of myocardial inflammatory disease than individuals with normal body mass index. Circulating levels of inflammatory cytokines might be considered to determine risk categories for development of cardiovascular complications in obese subjects. In addition, their reduction with pharmacological antagonists might prevent and/or control acute cardiovascular events and increase energy expenditure in obese patients, especially after surgical treatment, through reduction of cytokine inhibition of the hypothalamic-pituitary-thyroid axis.

Acromegaly and intestinal neoplasms.

Acromegalic subjects show increased frequency of neoplastic lesions in the colon and rectum with respect to the general population. Recent prospective studies using colonoscopy have shown a 3 time higher prevalence of intestinal polyps and up to 4 time increased presence of colorectal cancer in acromegaly, independently of sex, age, duration of disease and clinical status of the patients. The polyps are distributed throughout the extension of the large bowel and are often multiple, showing at least two different histologic types: hyperplastic and adenomatous. Sometimes they are associated with intestinal carcinomas. Pancolonoscopy is the procedure of choice for the diagnosis of large bowel neoplasms, even though it may be difficult to complete in these subjects because of the frequent presence of an enlarged and elongated colon. It shows a higher sensitivity and specificity compared to other tests such as the barium enema, fecal occult blood test and serum levels of carcinoembryonic antigen. Therefore, it is recommended to follow up acromegalic patients using pancolonoscopy to obtain early detection of neoplastic lesions in the large bowel.

Acromegaly and intestinal neoplasms.

Acromegalic subjects show increased frequency of neoplastic lesions in the colon and rectum with respect to the general population. Recent prospective studies using colonoscopy have shown a 3 time higher prevalence of intestinal polyps and up to 4 time increased presence of colorectal cancer in acromegaly, independently of sex, age, duration of disease and clinical status of the patients. The polyps are distributed throughout the extension of the large bowel and are often multiple, showing at least two different histologic types: hyperplastic and adenomatous. Sometimes they are associated with intestinal carcinomas. Pancolonoscopy is the procedure of choice for the diagnosis of large bowel neoplasms, even though it may be difficult to complete in these subjects because of the frequent presence of an enlarged and elongated colon. It shows a higher sensitivity and specificity compared to other tests such as the barium enema, fecal occult blood test and serum levels of carcinoembryonic antigen. Therefore, it is recommended to follow up acromegalic patients using pancolonoscopy to obtain early detection of neoplastic lesions in the large bowel.