174 research outputs found

    Altered Gene Expression, Mitochondrial Damage and Oxidative Stress: Converging Routes in Motor Neuron Degeneration

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    Motor neuron diseases (MNDs) are a rather heterogeneous group of diseases, with either sporadic or genetic origin or both, all characterized by the progressive degeneration of motor neurons. At the cellular level, MNDs share features such as protein misfolding and aggregation, mitochondrial damage and energy deficit, and excitotoxicity and calcium mishandling. This is particularly well demonstrated in ALS, where both sporadic and familial forms share the same symptoms and pathological phenotype, with a prominent role for mitochondrial damage and resulting oxidative stress. Based on recent data, however, altered control of gene expression seems to be a most relevant, and previously overlooked, player in MNDs. Here we discuss which may be the links that make pathways apparently as different as altered gene expression, mitochondrial damage, and oxidative stress converge to generate a similar motoneuron-toxic phenotype

    Determination of clenbuterol in human urine by GC-MS-MS-MS: confirmation analysis in antidoping control

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    This work presents a GC-MS-MS-MS method for the direct determination of clenbuterol in human urine. The method comprises a pretreatment procedure and the instrumental analysis of the derivatives performed by GC-MS3 (ion trap) with electron impact ionization. The GC-MS3 analysis allows isolation and characterization of specific fragments from the original (MS1) molecular structure, and in particular, those fragments originating from the precursor ion cluster (m/z = 335-337) characteristic of clenbuterol. The MS2 product fragment m/z = 300 is in turn used as a further precursor fragment giving rise to a MS3 spectrum specific for clenbuterol. MS4 fragmentation spectra were also investigated. However, further fragmentation of MS3 product ions does not lead to functional MS4 spectra nor to any significant increase in the signal-to-noise ratio. The sensitivity limit of the MS3 technique is lower than 0.2 mug/l, with a linear range between 0.5 and 5 mug/l, thus matching the basic requirements for antidoping analysis according to the guidelines of the International Olympic Committee. Due to its overall analytical performance, the method is presently being evaluated as a confirmation protocol to be followed to detect illicit clenbuterol administration to the athletes, and compared with reference GC-MS and GC-MS-MS techniques. (C) 2002 Elsevier Science B.V. All rights reserved

    Nanostructured spinel cobalt ferrites: Fe and Co chemical state, cation distribution and size effects by X-ray photoelectron spectroscopy

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    Nanostructured spinel cobalt ferrite samples having crystallite size ranging between 5.6 and 14.1 nm were characterized by X-ray photoelectron spectroscopy and X-ray induced Auger electron spectroscopy in order to determine the chemical state of the elements, the iron/cobalt ratio and the cation distribution within tetrahedral and octahedral sites. The presence of size-dependent trends in the binding energy of the main photoelectron peaks and in the kinetic energy of the X-ray induced O KLL signal was also investigated. The results showed that iron is present as FeIII and cobalt is present as CoII. The iron/cobalt ratio determined by XPS ranges between 1.8 and 1.9 and it is in very good agreement, within experimental uncertainty, with the expected 2 : 1 ratio. The percentage of Fe in octahedral sites ranges between 62% and 64% for all samples. The kinetic energy of the O KLL signals increases with crystallite size. These results are explained in terms of changes in the ionicity of the metal–oxygen bonds. The results of this investigation highlight how the XPS technique represents a powerful tool to investigate the composition, the chemical state and inversion degree of cobalt spinel ferrites, contributing to the comprehension of their properties

    Multiple regression model to analyze the total LOS for patients undergoing laparoscopic appendectomy

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    The rapid growth in the complexity of services and stringent quality requirements present a challenge to all healthcare facilities, especially from an economic perspective. The goal is to implement different strategies that allows to enhance and obtain health processes closer to standards. The Length Of Stay (LOS) is a very useful parameter for the management of services within the hospital and is an index evaluated for the management of costs. In fact, a patient's LOS can be affected by a number of factors, including their particular condition, medical history, or medical needs. To reduce and better manage the LOS it is necessary to be able to predict this value

    Geographic variation and environmental conditions as cofactors in Chlamydia psittaci association with ocular adnexal lymphomas: a comparison between Italian and African samples

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    A particular extra-nodal lymphoma type arises from B cells of the marginal zone (MZ) of mucosa-associated lymphoid tissue (MALT). The aetiology ofMZ lymphomas suggests that they are associated with chronic antigenic stimulation by microbial pathogens, among which Helicobacter pylori-associated gastricMALT lymphoma is the best studied. Recently, MALT lymphomas have been described in the context of chronic conjunctivitis, which can be associated with Chlamydia spp. infection. Studies from Italy showed the presence of Chlamydia psittaci in 87% of ocular adnexal lymphomas (OAL), and C. psittaci has been described in a large part of samples from Austria and Korea as well. However, this finding was not always confirmed by other studies, suggesting that the association with C. psittaci may depend on geographic heterogeneity. Interestingly, none of the studies up to now has been carried out in the African population, where a strong association between infectious agents and the occurrence of human neoplasms has been reported. This study was designed to investigate the possible association of Chlamydia psittaci in cases retrieved from Kenya, compared to cases from Italy. Our results showed that there was a marked variation between the two geographical areas in terms of association with C. psittaci, as 17% (5/30) of the samples from Italy were positive for C. psittaci, whereas no association with this pathogen was observed in any of the African samples (0/9), suggesting that other cofactors may determine the OAL occurrence in those areas. OAL cases are often characterized by down-regulation of p16/INK4a expression and promoter hypermethylation of the p16/ INK4a gene. Our results showed a partial methylation of p16/INK4a promoter in C. psittacinegative cases, whereas no hypermethylation of this gene was found in C. psittaci-positive cases, suggesting that mechanisms other than promoter hypermethylation lead to p16/ INK4a silencing in C. psittaci-positive cases. We may conclude that the role of epidemiologic, environmental and genetic factors, must be considered in the aetiology of this disease

    Pollutants monitoring and air quality evaluation in a confined environment: The ‘Majesty’ of Ambrogio Lorenzetti in the St. Augustine Church in Siena (Italy)

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    A monitoring campaign of the levels of some organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs), perfluoro alkylated substances (PFASs), chlorinated pesticides (4 isomers of hexachlorocyclohexane, hexachlorobenzene, 6 isomers and metabolites of DDT and dieldrin), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs), in different matrices (dust taken from the floor and under a wall painting and fragments of the 'Majesty' wall painting by Ambrogio Lorenzetti), was conducted in the historical museum of St. Augustine's church in Siena (Italy). Instrumental analyses were made by gas chromatography and liquid chromatography coupled with mass spectrometry. The results showed the presence of some organic pollutants (PAHs and PBDEs), whose interaction with the surfaces of works of art are not yet fully elucidated. The study was complemented by monitoring the air quality inside and outside the church for the detection of volatile organic compounds (VOCs); all the results showed low levels of air pollution. Copyright (C)2016 Turkish National Committee for Air Pollution Research and Control

    Effects of an online supervised exercise training in children with obesity during the COVID-19 pandemic

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    COVID-19 restrictions have dramatically reduced the active lifestyle and physical activity (PA) levels in the whole population, a situation that can contribute to weight gain and to develop obesity. To improve physical fitness (PF) in children with obesity during COVID-19 restrictions, sport specialists started to deliver physical training through tele-exercise. For these reasons, the aim of this study was to evaluate the effects of a 12-week online supervised training program in children with obesity on different PF components and PA levels. We enrolled a total of 40 Caucasian children (9 F/31 M; aged 11 +/- 1.9 years) with obesity. The data collection consisted of a series of anthropometric measures, the PAQ-C questionnaire, and PF tests, valid and reliable tools to assess PF in children. We used a Wilcoxon's t-test and a Student's t-test, as appropriate, to assess the differences before and after the training protocol. A total of 37 patients completed the training protocol and were considered in the analysis. Our results show an improvement in all the PF tests, a reduction in the BMI z-score, the waist circumference, and in the waist-to-height ratio, and an increased PA level. In conclusion, the results of our study show that an online supervised training program is effective to promote PA, improving PF and reducing the BMI z-score in children with obesity
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