287 research outputs found
Contribution of polymorphic variation of inositol hexakisphosphate kinase 3 (IP6K3) gene promoter to the susceptibility to late onset Alzheimer's disease
Maintenance of electric potential and synaptic transmission are energetically demanding tasks that neuronal metabolism must continually satisfy. Inability to fulfil these energy requirements leads to the development of neurodegenerative disorders, including Alzheimer's disease. A prominent feature of Alzheimer's disease is in fact neuronal glucose hypometabolism. Thus understanding the fine control of energetic metabolism might help to understand neurodegenerative disorders. Recent research has indicated that a novel class of signalling molecules, the inositol pyrophosphates, act as energy sensors. They are able to alter the balance between mitochondrial oxidative phosphorylation and glycolytic flux, ultimately affecting the cellular level of ATP. The neuronal inositol pyrophosphate synthesis relies on the activity of the neuron enriched inositol hexakisphosphate kinase 3 (IP6K3) enzyme. To verify an involvement of inositol pyrophosphate signalling in neurodegenerative disorders, we performed tagging single nucleotide polymorphism (SNP) analysis of the IP6K3 gene in patients with familial and sporadic late onset Alzheimer's disease (LOAD). Two SNPs in the 5'-flanking promoter region of the IP6K3 gene were found to be associated with sporadic LOAD. Characterizing the functionality of the two polymorphisms by luciferase assay revealed that one of them (rs28607030) affects IP6K3 promoter activity, with the G allele showing an increased activity. As the same allele has a beneficial effect on disease risk, this may be related to upregulation of IP6K3 expression, with a consequent increase in inositol pyrophosphate synthesis. In conclusion, we provide the first evidence for a contribution of genetic variability in the IP6K3 gene to LOAD pathogenesis
IP6K3 and IPMK variations in LOAD and longevity: evidence for a multifaceted signaling network at the crossroad between neurodegeneration and survival
Several studies reported that genetic variants predisposing to neurodegeneration were at higher frequencies in centenarians than in younger controls, suggesting they might favor also longevity.
IP6K3 and IPMK regulate many crucial biological functions by mediating synthesis of inositol poly- and pyrophosphates and by acting non-enzymatically via proteināprotein interactions. Our previous studies suggested they affect Late Onset Alzheimer Disease (LOAD) and longevity, respectively. Here, in the same sample groups, we investigated whether variants of IP6K3 also affect longevity, and variants of IPMK also influence LOAD susceptibility. We found that: i) a SNP of IP6K3 previously associated with increased risk of LOAD increased the chance to become long-lived, ii) SNPs of IPMK, previously associated with decreased longevity, were protective factors for LOAD, as previously observed for UCP4. SNP-SNP interaction analysis, including our previous data, highlighted phenotype-specific interactions between sets of alleles. Moreover, linkage disequilibrium and eQTL data associated to analyzed variants suggested mitochondria as crossroad of interconnected pathways crucial for susceptibility to neurodegeneration and/or longevity.
Overall, data support the view that in these traits interactions may be more important than single polymorphisms. This phenomenon may contribute to the non-additive heritability of neurodegeneration and longevity and be part of the missing heritability of these traits
Predictor Analysis in Radiofrequency Ablation of Benign Thyroid Nodules: A Single Center Experience
PURPOSE: To confirm the efficacy of ultrasound (US) guided radiofrequency ablation (RFA) in the treatment of benign thyroid nodules, we evaluated as primary outcome the technical efficacy and clinical success in a single center dataset. The secondary outcome was to find a correlation between nodulesā pre-treatment features and volume reduction rate (VRR) ā„75% at 12 months after RFA and during follow-up period. METHODS: This retrospective study included 119 consecutive patients (99 females, 20 males, 51.5 Ā± 14.4 years) with benign thyroid nodules treated in our hospital between October 2014 and December 2018 with a mean follow-up of 26.8 months (range 3ā48). Clinical and US features before and after RFA were evaluated by a US examination at 1, 3, 6, 12 months and annually thereafter up to 48 months. RESULTS: The median pre-treatment volume was 22.4Ā ml; after RFA we observed a statistically significant volume reduction from the first month (11.7Ā ml) to the last follow-up (p 22.4Ā ml (HR 0.54, p 0.036) were found to be independent positive and negative predictors of VRR ā„75% respectively. One-month post RFA VRR ā„50% represented the best positive predictor of technical success. CONCLUSIONS: This study confirmed the efficacy of RFA in the treatment of benign thyroid nodules. In particular we show that by selecting macrocystic nodules smaller than 22.4Ā ml better long-term response can be achieved, which is predicted by an early shrinkage of the nodule
Clinical characteristics of patients with endometrial cancer and adenomyosis
open11noA better endometrial cancer (EC) prognosis in patients with coexistent adenomyosis has been reported. Unfortunately, it is still unclear if this better prognosis is related to a more favorable clinical profile of adenomyosis patients. We aimed to evaluate differences in the clinical profiles of EC patients with and without adenomyosis. A systematic review and meta-analysis was performed by searching seven electronics databases for all studies that allowed extraction of data about clinical characteristics in EC patients with and without adenomyosis. Clinical characteristics assessed were: age, Body Mass Index (BMI), premenopausal status, and nulliparity. Mean difference in mean Ā± standard deviation (SD) or odds ratio (OR) for clinical characteristics between EC patients with and without adenomyosis were calculated for each included study and as a pooled estimate, and graphically reported on forest plots with a 95% confidence interval (CI). The Z test was used for assessing the overall effect by considering a p value < 0.05 as significant. Overall, eight studies with 5681 patients were included in the qualitative analysis, and seven studies with 4366 patients in the quantitative analysis. Pooled mean difference in mean Ā± SD between EC women with and without adenomyosis was ā1.19 (95% CI: ā3.18 to 0.80; p = 0.24) for age, and 0.23 (95% CI: ā0.62 to 1.07; p = 0.60) for BMI. When compared to EC women without adenomyosis, EC women with adenomyosis showed a pooled OR of 1.53 (95% CI: 0.92 to 2.54; p = 0.10) for premenopausal status, and of 0.60 (95% CI: 0.41 to 0.87; p = 0.007) for nulliparity. In conclusion, there are not significant differences in clinical characteristics between EC patients with and without adenomyosis, with the exception for nulliparity. Clinical features seem to not underlie the better EC prognosis of patients with adenomyosis compared to patients without adenomyosis.openCasadio P.; Raffone A.; Maletta M.; Travaglino A.; Raimondo D.; Raimondo I.; Santoro A.; Paradisi R.; Zannoni G.F.; Mollo A.; Seracchioli R.Casadio P.; Raffone A.; Maletta M.; Travaglino A.; Raimondo D.; Raimondo I.; Santoro A.; Paradisi R.; Zannoni G.F.; Mollo A.; Seracchioli R
Reentrant Spin-Peierls Transition in Mg-Doped CuGeO_3
We report a synchrotron x-ray scattering study of the diluted spin-Peierls
(SP) material Cu_{1-x}Mg_xGeO_3. In a recent paper we have shown that the SP
dimerization attains long-range order only for x < x_c = 0.022(0.001). Here we
report that the SP transition is reentrant in the vicinity of the critical
concentration x_c. This is manifested by broadening of the SP dimerization
superlattice peaks below the reentrance temperature, T_r, which may mean either
the complete loss of the long-range SP order or the development of a
short-range ordered component within the long-range ordered SP state. Marked
hysteresis and very large relaxation times are found in the samples with Mg
concentrations in the vicinity of x_c. The reentrant transition is likely
related to the competing Neel transition which occurs at a temperature similar
to T_r. We argue that impurity-induced competing interchain interactions play
an essential role in these phenomena.Comment: 5 pages, 4 embedded eps figure
A Genome-Wide Screening and SNPs-to-Genes Approach to Identify Novel Genetic Risk Factors Associated with Frontotemporal Dementia
Frontotemporal dementia (FTD) is the second most prevalent form of early onset dementia after Alzheimerās disease (AD). We performed a case-control association study in an Italian FTD cohort (n = 530) followed by the novel SNPs-to-genes approach and functional annotation analysis. We identified two novel potential loci for FTD. Suggestive SNPs reached p-values ~10-7 and OR > 2.5 (2p16.3) and 1.5 (17q25.3). Suggestive alleles at 17q25.3 identified a disease-associated haplotype causing decreased expression of -cis genes such as RFNG and AATK involved in neuronal genesis and differentiation, and axon outgrowth, respectively. We replicated this locus through the SNPs-to-genes approach. Our functional annotation analysis indicated significant enrichment for functions of the brain (neuronal genesis, differentiation and maturation), the synapse (neurotransmission and synapse plasticity), and elements of the immune system, the latter supporting our recent international FTD-GWAS. This is the largest genome-wide study in Italian FTD to date. Although our results are not conclusive, we set the basis for future replication studies and identification of susceptible molecular mechanisms involved in FTD pathogenesis
3D Patient-Specific Virtual Models for Presurgical Planning in Patients with Recto-Sigmoid Endometriosis Nodules: A Pilot Study
Background and Objective: In recent years, 3D printing has been used to support surgical planning or to guide intraoperative procedures in various surgical specialties. An improvement in surgical planning for recto-sigmoid endometriosis (RSE) excision might reduce the high complication rate related to this challenging surgery. The aim of this study was to build novel presurgical 3D models of RSE nodules from magnetic resonance imaging (MRI) and compare them with intraoperative findings. Materials and Methods: A single-center, observational, prospective, cohort, pilot study was performed by enrolling consecutive symptomatic women scheduled for minimally invasive surgery for RSE between November 2019 and June 2020 at our institution. Preoperative MRI were used for building 3D models of RSE nodules and surrounding pelvic organs. 3D models were examined during multi-disciplinary preoperative planning, focusing especially on three domains: degree of bowel stenosis, nodule's circumferential extension, and bowel angulation induced by the RSE nodule. After surgery, the surgeon was asked to subjectively evaluate the correlation of the 3D model with the intra-operative findings and to express his evaluation as "no correlation", "low correlation", or "high correlation" referring to the three described domains. Results: seven women were enrolled and 3D anatomical virtual models of RSE nodules and surrounding pelvic organs were generated. In all cases, surgeons reported a subjective "high correlation" with the surgical findings. Conclusion: Presurgical 3D models could be a feasible and useful tool to support surgical planning in women with recto-sigmoidal endometriotic involvement, appearing closely related to intraoperative findings
Mirror system of the RICH detector of the NA62 experiment
A large RICH detector is used in NA62 to suppress the muon contamination in the charged pion selection by a factor 100 in the momentum range between 15 and 35 GeV/c. The detector consists of a 17 m long tank (vessel), filled with neon gas at atmospheric pressure. Cherenkov light is reflected by a mosaic of 20 spherical mirrors with 17 m focal length, placed at the downstream end, and collected by 1952 photomultipliers (PMTs) placed at the upstream end. In this paper the characterization of the mirrors before installation and the mirror support system are described. The mirror installation procedure and the laser alignment are also illustrated
Spin-Glass State in
Magnetic susceptibility, magnetization, specific heat and positive muon spin
relaxation (\musr) measurements have been used to characterize the magnetic
ground-state of the spinel compound . We observe a spin-glass
transition of the S=1/2 spins below characterized
by a cusp in the susceptibility curve which suppressed when a magnetic field is
applied. We show that the magnetization of depends on the
magnetic histo Well below , the muon signal resembles the dynamical
Kubo-Toyabe expression reflecting that the spin freezing process in results Gaussian distribution of the magnetic moments. By means of
Monte-Carlo simulati we obtain the relevant exchange integrals between the spins in this compound.Comment: 6 pages, 16 figure
Finite-Size and surface effects in maghemite nanoparticles: Monte Carlo simulations
Finite-size and surface effects in fine particle systems are investigated by
Monte Carlo simulation of a model of a -FeO (maghemite) single
particle. Periodic boundary conditions have been used to simulate the bulk
properties and the results compared with those for a spherical shaped particle
with free boundaries to evidence the role played by the surface on the
anomalous magnetic properties displayed by these systems at low temperatures.
Several outcomes of the model are in qualitative agreement with the
experimental findings. A reduction of the magnetic ordering temperature,
spontaneous magnetization, and coercive field is observed as the particle size
is decreased. Moreover, the hysteresis loops become elongated with high values
of the differential susceptibility, resembling those from frustrated or
disordered systems. These facts are consequence of the formation of a surface
layer with higher degree of magnetic disorder than the core, which, for small
sizes, dominates the magnetization processes of the particle. However, in
contradiction with the assumptions of some authors, our model does not predict
the freezing of the surface layer into a spin-glass-like state. The results
indicate that magnetic disorder at the surface simply facilitates the thermal
demagnetization of the particle at zero field, while the magnetization is
increased at moderate fields, since surface disorder diminishes ferrimagnetic
correlations within the particle. The change in shape of the hysteresis loops
with the particle size demonstrates that the reversal mode is strongly
influenced by the reduced atomic coordination and disorder at the surface.Comment: Twocolumn RevTex format. 19 pages, 15 Figures included. Submitted to
Phys. Rev.
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