Sleep Enhances Consolidation of Memory Traces for Complex Problem-Solving Skills

Sleep consolidates memory for procedural motor skills, reflected by sleep-dependent changes in the hippocampal-striatal-cortical network. Other forms of procedural skills require the acquisition of a novel strategy to solve a problem, which recruit overlapping brain regions and specialized areas including the caudate and prefrontal cortex. Sleep preferentially benefits strategy and problem-solving skills over the accompanying motor execution movements. However, it is unclear how acquiring new strategies benefit from sleep. Here, participants performed a task requiring the execution of a sequence of movements to learn a novel cognitive strategy. Participants performed this task while undergoing fMRI before and after an interval of either a full night sleep, a daytime nap, or wakefulness. Participants also performed a motor control task, which precluded the opportunity to learn the strategy. In this way, we subtracted motor execution-related brain activations from activations specific to the strategy. The sleep and nap groups experienced greater behavioral performance improvements compared to the wake group on the strategy-based task. Following sleep, we observed enhanced activation of the caudate in addition to other regions in the hippocampal-striatal-cortical network, compared to wakefulness. This study demonstrates that sleep is a privileged time to enhance newly acquired cognitive strategies needed to solve problems.

Androgen-modulated p21 and p53 gene expression in human non-transformed epithelial prostatic cells in primary cultures

The prostate gland is under androgen control. The aim of the present study was to evaluate the expression of two genes that are regulators of the cell cycle, the p53 and p21 genes, in human non-transformed epithelial prostatic cells (HNTEPs) treated with different concentrations of hormones. Samples of prostate tissue were obtained from 10 patients between 60 and 77 years of age. HNTEP cells were grown in basal medium and treated with dihydrotestosterone (DHT) in different conditions for 4 h. A low concentration of DHT resulted in a significant increase in cell growth; this effect was eradicated by addition of the antiandrogen hydroxyflutamide. Furthermore, the low concentration of DHT induced lower mRNA levels in the p53 and p21 genes in HNTEP cells. In turn, high DHT concentrations induced a significant increase in the expression of the p53 and p21 genes. The present data suggest that the p53 and p21 genes play a role in the control of responsiveness and androgen dose-dependent cell proliferation in HNTEP cells. Further studies are required to assess the intracellular signaling pathway regulated by p53 and p21 under the influence of androgens and its implications for the pathophysiology of prostate diseases.

Estrogen receptor-alpha, bcl-2 and c-myc gene expression in fibroadenomas and adjacent normal breast: association with nodule size, hormonal and reproductive features

Fibroadenomas are the most common benign lump in females. The study of gene alterations and/or deregulation in reproductive years may help explain hormonal physiological processes involved in nodule development and evolution. The objective was to compare ER-alpha, c-myc, and bcl-2 gene expression in breast fibroadenomas and in normal tissue and evaluate menstrual cycle, parity, and oral contraceptive influences. Fifty-seven premenopausal women (14-49 years) undergoing surgical removal of fibroadenomas were selected. Samples from fibroadenomas and circumjacent normal tissue were obtained for RT-PCR paired analysis. Patients were divided in groups according to menstrual cycle, use of contraceptives and parity. Tissue from 32 patients was adequate for RT-PCR. Paired analysis showed higher expression of ER-alpha (P=0.012) and bcl-2 (P=0.001) in fibroadenomas than in normal breast, while c-myc presented a similar expression (P=0.655). ER-alpha was higher in fibroadenomas of patients in follicular phase versus contraceptive users and normal tissue (P=0.003); bcl-2 was higher in fibroadenomas of patients in luteal phase than in the normal samples from all groups (P=0.007). c-myc did not differ according to menstrual cycle, but was higher in fibroadenomas>3 cm versus<3 cm (P=0.015) and in nulliparous women (P=0.04). A positive correlation between c-myc levels and fibroadenoma diameter was demonstrated (r=0.536; P=0.007). Nulliparous mean nodule diameter was superior than parous women (P=0.008). In conclusion, the expression of ER-alpha, bcl-2 and c-myc depends on hormonal and reproductive factors, with a possible contribution to lump formation and evolution.

[The organization of a working group for the prevention of decubitus lesions]

The authors report the results of a two years monitoring program focused on patients at risk of and with bedsores in the general hospital of Castelfranco Veneto. The purpose of the multidisciplinary exercise (which saw the participation of nurses, pharmacists, doctors) was the activation and the evaluation of treatment protocols. The overall recruited sample included 679 patients, with a prevalence of 61% of lesions at the occasion of the first observation, and of 57% in the last one. The hardly quantitatively different prevalence is better understood from a qualitative point of view: the number of lesions per patients drops slightly from 1.9 to 1.7; one out of four of the "at risk" patients became "at no risk"; a 30% improvement is observed with respect to treatment efficacy. It is suggested that a positive effect may be obtained through a sustained attention to the problem and the careful definition of the interventions to be planned.