288 research outputs found
Psychiatric profile of motor subtypes of de novo drug-naïve Parkinson's disease patients
Background: Parkinson's disease (PD) is a heterogeneous neurodegenerative disorder. It is well established that different motor subtypes of PD evolve with different clinical courses and prognoses. The complete psychiatric profile underlying these different phenotypes since the very early stage of the disease is debated. Aims of the study: We aimed at investigating the psychiatric profile of the three motor subtypes of PD (akinetic-rigid, tremor-dominant, and mixed) in de novo drug-naïve patients with PD. Methods: Sixty-eight patients with PD, divided into 39 akinetic-rigid (AR), seven mixed (MIX), and 22 tremor-dominant (TD) patients underwent a complete assessment of psychiatric, cognitive, and motor symptoms. Results: No significant differences were found among groups. Conclusions: Our results suggest that a differentiation of the psychiatric symptoms associated with specific motor subtypes of PD is not detectable in de novo drug-naïve patients. Previous evidence that emerges later along the disease progression may be a consequence of the dopaminergic and nondopaminergic damage increase
Towards 3d multi-layer scaffolds for periodontal tissue engineering applications: Addressing manufacturing and architectural challenges
Reduced periodontal support, deriving from chronic inflammatory conditions, such as periodontitis, is one of the main causes of tooth loss. The use of dental implants for the replacement of missing teeth has attracted growing interest as a standard procedure in clinical practice. However, adequate bone volume and soft tissue augmentation at the site of the implant are important prerequisites for successful implant positioning as well as proper functional and aesthetic reconstruction of patients. Three-dimensional (3D) scaffolds have greatly contributed to solve most of the challenges that traditional solutions (i.e., autografts, allografts and xenografts) posed. Nevertheless, mimicking the complex architecture and functionality of the periodontal tissue represents still a great challenge. In this study, a porous poly(ε-caprolactone) (PCL) and Sr-doped nano hydroxyapatite (Sr-nHA) with a multi-layer structure was produced via a single-step additive manufacturing (AM) process, as a potential strategy for hard periodontal tissue regeneration. Physicochemical characterization was conducted in order to evaluate the overall scaffold architecture, topography, as well as porosity with respect to the original CAD model. Furthermore, compressive tests were performed to assess the mechanical properties of the resulting multi-layer structure. Finally, in vitro biological performance, in terms of biocompatibility and osteogenic potential, was evaluated by using human osteosarcoma cells. The manufacturing route used in this work revealed a highly versatile method to fabricate 3D multi-layer scaffolds with porosity levels as well as mechanical properties within the range of dentoalveolar bone tissue. Moreover, the single step process allowed the achievement of an excellent integrity among the different layers of the scaffold. In vitro tests suggested the promising role of the ceramic phase within the polymeric matrix towards bone mineralization processes. Overall, the results of this study demonstrate that the approach undertaken may serve as a platform for future advances in 3D multi-layer and patient-specific strategies that may better address complex periodontal tissue defects
Anisotropic hybridization probed by polarization dependent x-ray absorption spectroscopy in VI3 van der Waals Mott ferromagnet
Polarization dependent x-ray absorption spectroscopy was used to study the
magnetic ground state and the orbital occupation in bulk-phase VI van der
Waals crystals below and above the ferromagnetic and structural transitions.
X-ray natural linear dichroism and X-ray magnetic circular dichroism spectra
acquired at the V edges are compared against multiplet cluster
calculations within the frame of the ligand field theory to quantify the
intra-atomic electronic interactions at play and evaluate the effects of
symmetry reduction occurring in a trigonally distorted VI unit. We observed
a non zero linear dichroism proving the presence of an anisotropic charge
density distribution around the V ion due to the unbalanced
hybridization between the Vanadium and the ligand states. Such hybridization
acts as an effective trigonal crystal field, slightly lifting the degeneracy of
the ground state. However, the energy splitting associated to the
distortion underestimates the experimental band gap, suggesting that the
insulating ground state is stabilized by Mott correlation effects rather than
via a Jahn-Teller mechanism. Our results clarify the role of the distortion in
VI and establish a benchmark for the study of the spectroscopic properties
of other van der Waals halides, including emerging 2D materials with mono and
few-layers thickness, whose fundamental properties might be altered by reduced
dimensions and interface proximity
artificial neural network modeling of liquid thermal conductivity for alkanes ketones and silanes
The values of thermal conductivity λ at different temperatures for organic and inorganic compounds in the liquid phase is essential in the study of numerous processes, but experimental data are frequently not available with acceptable reliability or not available at all, since rigorous theoretical or semi-theoretical models of the liquid state are usually of poor practical use for engineering purposes. The Artificial Neural Network (ANN) approach is a very powerful tool and it can be a good indicator of the lowest limit achievable with a selected database and with a selected set of inputs. This study investigates the applicability of the ANN as an efficient tool for the prediction of pure organic compounds' thermal conductivity of three important families such as alkanes, ketones and silanes, for a wide range of temperatures. The families of n-alkanes, ketones and silanes were chosen to verify the general reliability of the proposed method when used in large temperature ranges for very different organic families, above all the silanes (compounds containing silicon), whose liquid thermal conductivity is experimentally investigated in very few cases. This method appears to be successful: in all reduced temperature range, along or near the saturation line, the average absolute deviations between calculated and experimental thermal conductivity data are 0.19% and the maximum absolute ones 2.44
Interplay of the electronic and lattice degrees of freedom in A_{1-x}Fe_{2-y}Se_{2} superconductors under pressure
The local structure and electronic properties of RbFeSe
are investigated by means of site selective polarized x-ray absorption
spectroscopy at the iron and selenium K-edges as a function of pressure. A
combination of dispersive geometry and novel nanodiamond anvil pressure-cell
has permitted to reveal a step-like decrease in the Fe-Se bond distance at
GPa. The position of the Fe K-edge pre-peak, which is directly
related to the position of the chemical potential, remains nearly constant
until GPa, followed by an increase until GPa. Here, as in
the local structure, a step-like decrease of the chemical potential is seen.
Thus, the present results provide compelling evidence that the origin of the
reemerging superconductivity in FeSe in vicinity of a
quantum critical transition is caused mainly by the changes in the electronic
structure
Medication use in Italian nursing homes: preliminary results from the national monitoring system
Background: The aging population has increased concerns about the affordability, quality, and nature of long-term care for older people, emphasizing the role of nursing homes. Unlike acute hospital and primary care, there is a lack of drug consumption data in long-term care to understand regional or national healthcare policies. Objectives: This study aimed to describe medication consumption by older adults and expenditure in Italian nursing homes (NHs). Methods: Data on drug consumption and costs from the administrative medicine informational flows that detect medicines packages supplied to patients in health facilities and NHs were used. Data on the characteristics of the healthcare residence were from the Italian Health Ministry. Records for the year 2019, selecting the nursing homes exclusively providing elderly or mixed (elderly and disabled) were used. Results: In 2019, the total expenditure on medicines in NHs amounted to 25.38 million euros, the average cost to 1.30 and the expenditure per bed to 436.18 euros. Cardiovascular drugs were the highest-consuming therapeutic class (177.0 defined daily doses—DDDs/100 days of NH stay; 22.2% of total) followed by drugs acting on the alimentary tract and metabolism (167.6% and 21.0%) and blood drugs (160.4% and 20.1%). The treatment of hypertension and heart failure was widely the most frequently used, with the consumption being driven mainly by furosemide and ramipril. Antiulcer drugs were used on average in more than half of the days of NH stay (58.5 DDDs/100 days of NH stay), representing a therapeutic category for which deprescribing initiatives are recommended. On average, almost all patients received a dose of benzodiazepines, antipsychotics and antidepressants (37.6, 35.9, and 17.7 DDDs/100 days of NH stay, respectively), confirming the high prevalence of use for these medicines. Antibiotics reached 6.8 DDDs/100 days of NH stay. Conclusion: The availability of data in this specific setting allows the identification of the main interventions toward improving appropriateness and represents a challenge for drug utilization research. Data from this study suggest that proton pump inhibitors (PPIs), benzodiazepines and antibacterials can be areas of improving prescribing appropriateness
Medication Use and Costs Among Older Adults Aged 90Â Years and Older in Italy
Older adults are often affected by multiple chronic conditions and experience geriatric syndromes that may affect the risk/benefit profile of medications. Little is known about the use of such medications in the older population. This article describes medication use and costs in Italian adults aged ≥90 years. Data from the 2019 Pharmaceutical Prescriptions database, concerning data on medications reimbursed by the Italian National Health Service, were analyzed in terms of prevalence and amount of use expressed as defined daily dose/1,000 users (DDD/1,000 users/day), accounting for different age-groups and sex. All individuals aged ≥90 years used at least one medication, with a mean number of 3128 DDD/1,000 users/day corresponding to an annual cost of 683 euros per user. Both use and costs linearly decreased with increasing age, with men accounting for a higher amount of DDD/1,000 users and costs than women across all age-groups. Antihypertensives (1330 DDD/1,000 inhabitants), antiplatelet agents (337 DDD/1,000 inhabitants), medications for peptic ulcer and gastroesophageal reflux (328 DDD/1,000 inhabitants), and lipid-lowering agents (166 DDD/1,000 inhabitants) were the most frequently used medications. We observed a progressive decrease in the usage of the majority of medications with increasing age, with the exception of antibiotics and antipsychotics. Individuals aged ≥90 years used a lower DDD/1,000 users, with an associated decrease in annual costs. The persistent use of preventive medications highlights the potential lack of awareness regarding medication rationalization and guidance for optimizing prescriptions. Our findings highlight the need for further initiatives to improve medications’ appropriateness in these older age-groups
Involvement of subcortical brain structures during olfactory stimulation in multiple chemical sensitivity
Multiple chemical sensitivity (MCS) patients usually react to odour compounds and the majority of neuroimaging studies assessed, especially at the cortical level, many olfactory-related correlates. The purpose of the present study was to depict sub-cortical metabolic changes during a neutral (NC) and pure (OC) olfactory stimulation by using a recently validated 18F-2-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography/computer tomography procedure in 26 MCS and 11 healthy (HC) resting subjects undergoing a battery of clinical tests. Twelve subcortical volumes of interest were identified by the automated anatomical labeling library and normalized to thalamus FDG uptake. In both groups, when comparing OC to NC, the within-subjects ANOVA demonstrated a relative decreased metabolism in bilateral putamen and hippocampus and a relative increased metabolism in bilateral amygdala, olfactory cortex (OLF), caudate and pallidum. The between-groups ANOVA demonstrated in MCS a significant higher metabolism in bilateral OLF during NC. As in HC subjects negative correlations were found in OC between FDG uptake in bilateral amygdala and hippocampus and odor pleasantness scale, the latter positively correlated with MCS subjects\u27 bilateral putamen FDG uptake in OC. Besides FDG uptake resemblances in both groups were found, for the first time a relative higher metabolism increase in OLF in MCS subjects at rest with respect to HC was found. When merging this aspect to the different subcortical FDG uptake correlations patterns in the two groups, the present study demonstrated to describe a peculiar metabolic index of behavioral and neurological aspects of MCS complaints
Ryanodine receptor 1 (RYR1) mutations in two patients with tubular aggregate myopathy
Two likely causative mutations in the RYR1 gene were identified in two patients with myopathy with tubular aggregates, but no evidence of cores or core-like pathology on muscle biopsy. These patients were clinically evaluated and underwent routine laboratory investigations, electrophysiologic tests, muscle biopsy and muscle magnetic resonance imaging (MRI). They reported stiffness of the muscles following sustained activity or cold exposure and had serum creatine kinase elevation. The identified RYR1 mutations (p.Thr2206Met or p.Gly2434Arg, in patient 1 and patient 2, respectively) were previously identified in individuals with malignant hyperthermia susceptibility and are reported as causative according to the European Malignant Hyperthermia Group rules. To our knowledge, these data represent the first identification of causative mutations in the RYR1 gene in patients with tubular aggregate myopathy and extend the spectrum of histological alterations caused by mutation in the RYR1 gene
Identification of hidden orbital contributions in the La_{0.65} Sr_{0.35} MnO_{3} valence band
Hybridization of electronic states and orbital symmetry in transition metal oxides are generally considered key ingredients in the description of both their electronic and magnetic properties. In the prototypical case of La_{0.65} Sr_{0.35} MnO_{3} (LSMO), a landmark system for spintronics applications, a description based solely on Mn 3d and O 2p electronic states is reductive. We thus analyzed elemental and orbital distributions in the LSMO valence band through a comparison between density functional theory calculations and experimental photoelectron spectra in a photon energy range from soft to hard x rays. We reveal a number of hidden contributions, arising specifically from La 5p, Mn 4s, O 2s orbitals, considered negligible in previous analyses; our results demonstrate that all these contributions are significant for a correct description of the valence band of LSMO and of transition metal oxides in general
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