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Receiver array coils in magnetic resonance imaging systems are used to pick up the signals emitted by the nuclei with high signal-to-noise ratio and a large region of sensitivity. Especially in low-field magnetic resonance systems, receiver coil performance plays a significant role in image quality. Moreover, since the magnetic resonance scanner shielding system strongly modifies resonance frequencies and field distribution, the array coils performance should be evaluated in dependence on the shield position. In this paper, we describe the use of a numerical solver based on finite-difference time-domain method to evaluate coil performances also considering the presence of radiofrequency shields. In particular, this paper deals with coupling and shielding in phased array coils at low field: we analyzed a classic two circular elements array and a novel two elements array coil both designed for the application in a 0.5 T open magnetic resonance scanner. The prototypes of the arrays were tested by laboratory workbench in order to validate the simulated data and experiments were also done in real low field magnetic resonance scanner by using the novel coil.

The well-scaled transition to the diffusion limit in the framework of the theory of continuous-time random walk (CTRW)is presented starting from its representation as an infinite series that points out the subordinated character of the CTRW itself. We treat the CTRW as a combination of a random walk on the axis of physical time with a random walk in space, both walks happening in discrete operational time. In the continuum limit we obtain a generally non-Markovian diffusion process governed by a space-time fractional diffusion equation. The essential assumption is that the probabilities for waiting times and jump-widths behave asymptotically like powers with negative exponents related to the orders of the fractional derivatives. By what we call parametric subordination, applied to a combination of a Markov process with a positively oriented L\'evy process, we generate and display sample paths for some special cases., Comment: 28 pages, 18 figures. Workshop 'In Search of a Theory of Complexity'. Denton, Texas, August 2005

In this paper, a time series analysis of collisional effects in a numerical simulation of a coasting beam transverse dynamics is presented. The simulation performs a numerical integration of the Hamilton's equations of a two-dimensional system of particles, describing the transverse dynamics of the beam. Then, an analysis of the time series generated has been applied in order to describe the dynamics of the system by means of the mean field equations, with the addition of a stochastic process in order to model Coulomb collisions.

This study was performed to evaluate the relation between a stable personality trait, a mood state and immune response to an examination stress. A self-reported measure of emotional stability (BFQ-ES scale) was obtained in a sample (n = 39) randomly selected from 277 cadets; this personality trait was also investigated by completing a neuroticism scale (Eysenck personality inventory) and a trait-anxiety scale (STAI). Natural killer (NK) cell activity was measured at baseline, long before the examination time and the examination day. The state-anxiety scale evaluated the response to the stressful stimulus. Taking subjects all together, the academic task did not result in significant modification over baseline in NK cell activity. Subjects were then divided into three groups based on emotional stability and state-anxiety scores: high emotional stability/low anxiety, medium, and low emotional stability/high anxiety. Examination stress induced significant increases in NK cell activity in the high emotional stability/low anxiety group, no effect in the medium group, and significant decreases in the low emotional stability/high anxiety group. The repeated-measure ANOVA revealed a significant interaction of group x period (baseline vs. examination) for both lytic units and percent cytolysis. The results did not change after introducing coffee and smoking habits as covariates. Our findings suggest that the state-anxiety acts in concert with a stable personality trait to modulate NK response in healthy subjects exposed to a psychological naturalistic stress. The relation between anxiety and poor immune control has been already described, whereas the ability of emotional stability to associate with an immunoenhancement has not yet reported. The peculiarity of our population, a very homogeneous and healthy group for life style and habits, can have highlighted the role of emotional stability, and may account for the difference with other studies.

Damages to the nervous system are the primarily cause of neuropathy and chronic pain. Current pharmacological treatments for neuropathic pain are not able to prevent or revert morphological and molecular consequences of tissue injury. On the other hand, many neurotrophins, like nerve growth factor (NGF), paired off restorative effects with hyperalgesia. Interestingly, the glial cell line-derived neurotrophic factors GDNF and Artemin (ARTN) seem to support neuron survival and to normalize abnormal pain behaviour. In the present research protein levels of NGF, GDNF and ARTN were evaluated in a rat model of peripheral neuropathy, the chronic constriction injury (CCI). NGF was increased by CCI in the ipsilateral dorsal root ganglia (DRG), in the spinal cord and in the periaqueductal grey matter (PAG). On the contrary, ARTN was decreased bilaterally in DRG, spinal cord and PAG. GDNF levels decreased in ipsilateral DRG, whereas the constriction did not modify its expression in the central nervous system districts. Repeated treatments with the antihyperalgesic and neuroregenerative compound acetyl-l-carnitine (ALCAR; 100 mgkg(-1) i.p. twice daily for 15 days) was able to prevent the increase of NGF levels. In conditions of pain relief ALCAR normalized peripheral and central alterations of GDNF and ARTN levels. Characteristically, sham animals that underwent the same ALCAR treatment, showed increased levels of ARTN both in the DRG and in the spinal cord. These data offer a new point of view on the mechanism of the antihyperalgesic as well as the neuroprotective effect of ALCAR.

Evidence has accumulated for the involvement of Ca2+ in the pathophysiology of mood disorders. Elevations in both resting and stimulated intracellular Ca2+ levels in patients with affective disorders have been reported. The role of inositol-1,4,5-trisphosphate receptors (InsP3Rs), which allow mobilization of intracellular Ca2+ stores, was, then, investigated in the mouse forced swimming test. InsP3R antagonists (heparin, xestospongin C) as well as an inositol monophosphatase inhibitor (LiCl) showed an antidepressant activity of intensity comparable to clinically used antidepressants. InsP3Rl, InsP3R2 and InsP3R3 knockdown mice were obtained to investigate the role of InsP3R isoforms. We generated mice carrying a cerebral knockdown of InsP3Rl, InsP3R2 and InsP3R3 proteins by administering antisense oligonucleotides complementary to the sequence of InsP3Rl, InsP3R2 and InsP3R3. These antisense-treated mice showed a specific InsP3R protein level reduction in the mouse cerebral cortex and hippocampus, demonstrated by immunoblotting, immunoprecipitation and immunocytochemistry experiments. Knockdown mice for each InsP3R isoforms showed an antidepressant behaviour and the induced phenotype was reversible disappearing 7 days after the end of the treatment. The absence of impairment of locomotor activity and spontaneous mobility in InsP3R knockdown mice was revealed. These results indicate the involvement of the InsP3R-mediated pathway in the modulation of depressive conditions and may be useful for the development of new therapeutical strategies for the treatment of mood disorders.

A series of new 1,8-naphthyridine and quinoline derivatives were synthesized and evaluated for their cannabinoid receptor affinity. In particular, compounds 2, 5, 11, and 13 showed a high CB2 affinity and CB2 versus CB1 selectivity, in agreement with molecular modeling studies. Furthermore, compound 2 also exhibited in vivo antinociceptive effects.

Time series models showing power law tails in autocorrelation functions are common in econometrics. A special non-Markovian model for such kind of time series is provided by the random walk introduced by Gorenflo et al. as a discretization of time fractional diffusion. The time series so obtained are analyzed here from a numerical point of view in terms of autocorrelations and covariance matrices.

For space-time fractional diffusion equations a theory of discrete-space discrete-time random walks, analogous to the theory of continuous-time random walks, is presented. The essential assumption is that the probabilities for waiting times and jump-widths behave asymptotically like powers with negative exponents related to the orders of the fractional derivatives. Properly scaled passage to the diffusion limit then leads to the space-time fractional diffusion equation. Illustrating examples are given, numerical results and plots of simulations are displayed.

Keshan disease is a cardiomyopathy of unknown origin reported in some areas of China. Because of epidemiologic features, this disease was ascribed to an infectious agent, likely a Coxsackie virus, but it has also been thought to depend on selenium deficiency, mainly because selenite is effective in its prophylaxis. We examined the hypothesis that pharmacological activity of selenite on Coxsackie virus growth was associated with prevention of Keshan disease. We studied the antiviral effects of three selenium compounds on Coxsackie virus B5 replication: five microM selenite reduced viral replication, whilst 10 microM selenate and selenomethionine did not exhibit any antiviral activity. The inhibitory activity of selenite on viral replication was due to its toxicity following its interaction with thiols, as that activity could be blocked by dithiothreitol, a sulfhydryl-protecting agent known to reverse several toxic effect of selenite. Zinc, another inhibitor of selenite toxicity, also counteracted the antiviral effect of selenite. The selenium compounds showed only limited activity against herpes simplex 1 virus and IHD strain of vaccinia virus. A direct inhibitory effect of selenite on Coxsackie virus replication might explain the efficacy demonstrated by this compound in the prophylaxis of Keshan disease.

In this study, we discuss some relevant aspects concerning the determination of selenium in biological materials with special reference to fluorometry and hydride generation atomic absorption spectroscopy (HG-AAS) techniques. The two methods may be applied without modifications to the analysis of Se in a wide spectrum of specimen types, and we describe their reliability in serum and hair analyses. Thirty-six independent control serum samples, the concentrations of which were unknown to the analyst, were analyzed in duplicate using both techniques in the Italian External Quality Assessment Scheme (EQAS). Accuracy was assessed by comparing Se values with those previously assigned by the organizers of the scheme using graphite furnace atomic absorption spectrometry (GF-AAS), which is the most frequently used technique for selenium determination in serum among the participants in the Italian EQAS. The results confirmed that fluorometry has a higher degree of accuracy than HG-AAS: the mean differences between observed and expected values were 1.5 μg/liter (95% confidence interval, -1.06 to 3.97) for fluorometry and -1.1 μg/liter (95% confidence interval, -5.05 to 2.76) for Hg-AAS. We also report some results obtained for the determination of Se in hair. Since a critical step in hair preparation is the pretreatment for removal of external contamination, we compared six different washing procedures. In general, Se is poorly leached from hair, but the efficiency of removal differed with the substance used, ranging from 0 to 13% of the original content. A nonionic detergent like Triton X-100 offers the advantage of safe working conditions and a substantial reduction in costs compared with organic solvents. Lastly, in a consistent group (n = 131) of women, Se in hair was found to be strongly reduced by the use of dye (389.9 ng/g vs 498.7 ng/g, P < 0.001). We recommend recording information on cosmetic treatments when hair is collected to evaluate Se reference values in epidemiological studies.

Medical records of newly diagnosed non-insulin-dependent diabetic patients attending a Diabetic Centre in Modena, northern Italy, during the period 1985-88 were reviewed to analyze the prevalence of hypertension at age of diagnosis of diabetes and its association with selected risk factors. The prevalence of hypertension was also determined in a representative sample of control subjects. In the multivariate analysis, greater body mass index and older age, but not smoking, were strongly associated with increased rates of hypertension both in control and in diabetic subjects. In diabetic patients, family history of diabetes, defined as presence of diabetes in close relatives, was not significantly associated with hypertension, while rates of hypertension were significantly lower in patients who reported at least one parent affected by diabetes. After adjustment for age and body mass index, newly diagnosed non-insulin-dependent diabetes was not an independent risk factor for hypertension. These findings seem to be consistent with the hypothesis that diabetes and hypertension are not linked by a common genetic background.

We have measured the levels of zinc in serum (Zn-S) and in hair (Zn-H) in 391 adolescents, in good health, aged between 11 and 14 years. To evaluate the relationship between zinc status and sexual maturation we have analyzed, in the same subjects, the serum concentrations of the following hormones: luteinizing hormone (LH), follicle stimulating hormone (FSH), dehydroepiandrosterone-sulphate (DHA-S), testosterone (T) and estradiol (E2). No significant relationship between zinc in the biological samples and the hormones measured in all subjects was observed; only in prepuberal females was a positive correlation found between Zn-S and E2. A significant relationship between Zn-S and LH was observed only for males with short stature or low weight (less than 25th percentile) (r = 0.359, p = 0.010; r = 0.47, p = 0.008, respectively). When prepuberal males with short stature were considered, a significant association between Zn-S and T appeared (r = 0.399, p = 0.006). In females with short stature (less than 25th percentile), partial correlation coefficients showed a significant association between FSH and zinc in hair (r = 0.435, p = 0.004), while in girls with low weight, FSH appeared positively related to zinc in hair (r = 0.470, p = 0.003) and negatively related to zinc in serum (r = -0.320, p = 0.050). Our results suggest that zinc plays an important role in the metabolism of hormones linked to sexual maturation.

s / Digestive and Liver Disease 47S (2015) e221–e225 e225 age of these patients was 61 years (SD 12); 53% were female. Compared to HCV patients without steatosis (3347), in patients with steatosis: BMI was ≥25 in 44% vs. 36% (p

s / Digestive and Liver Disease 46 (2014) e18–e42 e29 Our data provide new insights in p53 involvement in NAFLD pathogenesis, highlighting its role in the modulation of copper homeostasis. http://dx.doi.org/10.1016/j.dld.2014.01.066