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81.
Roberta Papagni Carmen Pellegrino Francesco Di Gennaro Giulia Patti Aurelia Ricciardi Roberta Novara Sergio Cotugno Maria Musso Giacomo Guido Luigi Ronga Stefania Stolfa Davide Fiore Bavaro Federica Romanelli Valentina Totaro Rossana Lattanzio Giuseppina De Iaco Fabrizio Palmieri Annalisa Saracino Gina Gualano 《International journal of molecular sciences》2022,23(7)
Vitamin D plays a crucial role in many infectious diseases, such as tuberculosis (TB), that remains one of the world’s top infectious killers with 1.5 million deaths from TB in 2021. Vitamin D suppresses the replication of Mycobacterium tuberculosis in vitro and showed a promising role in TB management as a result of its connection with oxidative balance. Our review encourages the possible in vivo benefit of a joint administration with other vitamins, such as vitamin A, which share a known antimycobacterial action with vitamin D. However, considering the low incidence of side effects even at high dosages and its low cost, it would be advisable to assess vitamin D level both in patients with active TB and high-risk groups and administer it, at least to reach sufficiency levels. 相似文献
82.
Tommaso Schirinzi Illari Salvatori Henri Zenuni Piergiorgio Grillo Cristiana Valle Giuseppina Martella Nicola Biagio Mercuri Alberto Ferri 《International journal of molecular sciences》2022,23(18)
Mitochondria are central in the pathogenesis of Parkinson’s disease (PD), as they are involved in oxidative stress, synaptopathy, and other immunometabolic pathways. Accordingly, they are emerging as a potential neuroprotection target, although further human-based evidence is needed for therapeutic advancements. This study aims to shape the pattern of mitochondrial respiration in the blood leukocytes of PD patients in relation to both clinical features and the profile of cerebrospinal fluid (CSF) biomarkers of neurodegeneration. Mitochondrial respirometry on the peripheral blood mononucleate cells (PBMCs) of 16 PD patients and 14 controls was conducted using Seahorse Bioscience technology. Bioenergetic parameters were correlated either with standard clinical scores for motor and non-motor disturbances or with CSF levels of α-synuclein, amyloid-β peptides, and tau proteins. In PD, PBMC mitochondrial basal respiration was normal; maximal and spare respiratory capacities were both increased; and ATP production was higher, although not significantly. Maximal and spare respiratory capacity was directly correlated with disease duration, MDS-UPDRS part III and Hoehn and Yahr motor scores; spare respiratory capacity was correlated with the CSF amyloid-β-42 to amyloid-β-42/40 ratio. We provided preliminary evidence showing that mitochondrial respiratory activity increases in the PBMCs of PD patients, probably following the compensatory adaptations to disease progression, in contrast to the bases of the neuropathological substrate. 相似文献
83.
Paola Piscopo Valeria Manzini Roberto Rivabene Alessio Crestini Loredana Le Pera Elisabetta Pizzi Caterina Veroni Giuseppina Talarico Martina Peconi Anna Elisa Castellano Carmelo DAlessio Giuseppe Bruno Massimo Corbo Nicola Vanacore Eleonora Lacorte 《International journal of molecular sciences》2022,23(21)
The most frequently used biomarkers to support the diagnosis of Alzheimer’s Disease (AD) are Aβ42, total-Tau, and phospho-tau protein levels in CSF. Moreover, magnetic resonance imaging is used to assess hippocampal atrophy, 18F-FDG PET to identify abnormal brain metabolism, and PET imaging for amyloid deposition. These tests are rather complex and invasive and not easily applicable to clinical practice. Circulating non-coding RNAs, which are inherently stable and easy to manage, have been reported as promising biomarkers for central nervous system conditions. Recently, circular RNAs (circRNAs) as a novel class of ncRNAs have gained attention. We carried out a pilot study on five participants with AD and five healthy controls (HC) investigating circRNAs by Arraystar Human Circular RNA Microarray V2.0. Among them, 26 circRNAs were differentially expressed (FC ≥ 1.5, p < 0.05) in participants with AD compared to HC. From a top 10 of differentially expressed circRNAs, a validation study was carried out on four up-regulated (hsa_circRNA_050263, hsa_circRNA_403959, hsa_circRNA_003022, hsa_circRNA_100837) and two down-regulated (hsa_circRNA_102049, hsa_circRNA_102619) circRNAs in a larger population. Moreover, five subjects with mild cognitive impairment (MCI) were investigated. The analysis confirmed the upregulation of hsa_circRNA_050263, hsa_circRNA_403959, and hsa_circRNA_003022 both in subjects with AD and in MCI compared to HCs. We also investigated all microRNAs potentially interacting with the studied circRNAs. The GO enrichment analysis shows they are involved in the development of the nervous system, and in the cellular response to nerve growth factor stimuli, protein phosphorylation, apoptotic processes, and inflammation pathways, all of which are processes related to the pathology of AD. 相似文献
84.
Mattia Emanuela Ligotti Anna Aiello Giulia Accardi Anna Calabr Marcello Ciaccio Claudia Colomba Danilo Di Bona Bruna Lo Sasso Fanny Pojero Antonino Tuttolomondo Calogero Caruso Giuseppina Candore Giovanni Duro 《International journal of molecular sciences》2022,23(24)
Natural killer (NK) cells play a role in defence against viral infections by killing infected cells or by producing cytokines and interacting with adaptive immune cells. Killer immunoglobulin-like receptors (KIRs) regulate the activation of NK cells through their interaction with human leucocyte antigens (HLA). Ninety-six Sicilian patients positive to Human Immunodeficiency Virus-1 (HIV) and ninety-two Sicilian patients positive to SARS-CoV-2 were genotyped for KIRs and their HLA ligands. We also included fifty-six Sicilian patients with chronic hepatitis B (CHB) already recruited in our previous study. The aim of this study was to compare the distribution of KIR–HLA genes/groups of these three different infected populations with healthy Sicilian donors from the literature. We showed that the inhibitory KIR3DL1 gene and the KIR3DL1/HLA-B Bw4 pairing were more prevalent in individual CHB. At the same time, the frequency of HLA-C2 was increased in CHB compared to other groups. In contrast, the HLA-C1 ligand seems to have no contribution to CHB progression whereas it was significantly higher in COVID-19 and HIV-positive than healthy controls. These results suggest that specific KIR–HLA combinations can predict the outcome/susceptibility of these viral infections and allows to plan successful customized therapeutic strategies. 相似文献
85.
Giuseppina Adiletta Gerardo Iannone Paola Russo Giovanni Patimo Salvatore De Pasquale Marisa Di Matteo 《International Journal of Food Science & Technology》2014,49(12):2602-2609
The paper investigated the effect of hot‐air drying (50, 60 °C) on the physical properties of cylindrical eggplant samples. Drying kinetics, water profiles along longitudinal and transversal sample sections through nuclear magnetic resonance imaging (MRI) and volumetric shrinkage were determined. During the drying process at 50 °C, the volume of removed water was found lower than the reduction in sample volume, while at 60 °C it was higher. MRI showed that the water migration mainly occurs transversally than longitudinally. The curves of mass water loss obtained by both the standard weighting method and MRI showed conformity. Experimental data of moisture ratio and of shrinkage volume were fitted using empirical models available in the literature. This preliminary study showed that the nondestructive MRI technique offers the possibility to study water distribution in food during drying processes. The quantitative moisture distribution maps allow future development and verification of models for prediction of mass transport phenomena in foods during drying. 相似文献
86.
Valentina Aina Loredana Bergandi Gigliola Lusvardi Gianluca Malavasi Flora E. Imrie Iain R. Gibson Giuseppina Cerrato Dario Ghigo 《Materials science & engineering. C, Materials for biological applications》2013,33(3):1132-1142
A series of Sr-substituted hydroxyapatites (HA), of general formula Ca(10 ? x)Srx(PO4)6(OH)2, where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials.A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition.To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl2, in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in HA has a positive effect on MG-63 cells. In contrast, Sr ions alone, at the concentrations released by Sr-HA (1.21–3.24 ppm), influenced neither cell proliferation nor differentiation. Thus the positive effects of Sr in Sr-HA materials are probably due to the co-action of other ions such as Ca and P. 相似文献
87.
Renata Viscuso Giuseppina Camiolo Danilo G.M. Vitale 《Microscopy research and technique》2015,78(7):577-586
A study by both optical and electron microscopy has been carried out on the spermatheca of Eupholidoptera chabrieri bimucronata and Uromenus brevicollis trinacriae (Orthoptera: Tettigoniidae). In both the examined species, the spermatheca consists of a sac/kidney‐shaped seminal receptacle and a more or less tortuous spermathecal duct that opens into the common oviduct. The wall of both the organs consists of a pseudostratified epithelium surmounted by a cuticular intima; the latter is made up of a thicker endocuticle and an epicuticle. The epithelium shows two different cell types, irregularly arranged and with well differentiated functions: cuticle‐forming and gland cells. In both the species, the cuticle‐forming cells perform other functions, in addition to producing the cuticular intima. The gland cells never come in contact with the cuticular intima, have inside the reservoir a secretion whose appearance can diversify also in contiguous zones of the seminal receptacle. Based on our findings in both the species, the functions of the seminal receptacle would differ from those of the spermathecal duct. In the latter, some areas of the wall of the connecting tract show an activity of lysis, by contiguous epithelial cells, that could play a role in control and selection of spermatozoa. As for the feather‐shaped spermatodesms, similar in both the species, freeze‐fracture observations have shown that the acrosome of each spermatozoon regularly covers three‐quarters of the extension of the acrosome of the following spermatozoon. Finally, the significance of our findings, compared with what is known in literature, is discussed. Microsc. Res. Tech. 78:577–586, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
88.
Ambra Giovannelli Erika M. Archilei Giuseppina Di Lorenzo Coriolano Salvini Muhammad A. Bashir Giuseppe Messina 《国际能源研究杂志》2021,45(1):355-378
For power production, the emerging technologies of supercritical carbon dioxide (S‐CO2) cycles show potential advantages if compared to conventional plants. The current bottleneck in exploiting such cycles is the development of novel components such as turbomachines and heat‐exchangers. This paper focuses on the layout arrangement and machinery design of a novel power‐block for a 10 to 15 MW supercritical carbon dioxide plant. The applied design procedure involves 0D and 1D models implemented using an in‐house Fortran code, and 3D computational fluid dynamics ( CFD) analyses using ANSYS‐CFX. Novel configurations of the power block were designed, starting with the same primary thermal source. At nominal conditions, expected overall output powers from 13.2 to 16.2 MW were found. Finally, some qualitative considerations were included in the discussion to compare the analysed arrangements. 相似文献
89.
Giuseppina Montante Franco Magelli Alessandro Paglianti 《Chemical Engineering Research and Design》2013
In this work, a novel stirred tank for the production of biohydrogen by fermentation of organic wastes is presented. The bioreactor is designed for ensuring effective mixing of the liquid phase, full contact between the substrate and the biofilm and energy efficient hydrogen recovery. A vortex-ingesting dual impeller stirred vessel equipped with a central draft tube containing the support for the attached-growth process is proposed. The local hydrodynamics features of the system have been investigated experimentally by Particle Image Velocimetry (PIV) and Digital Image Processing methods for determining the velocity fields of the two phases, the bubble size distribution and the central vortex shape at different working conditions. Additionally, power consumption was measured by a strain gauge technique for quantifying energy requirements. The results confirm that the reactor hydrodynamics characteristics are adequate for the selected application and that it can ensure the external gas recirculation towards a gas separation unit for the hydrogen recovery and purification, without additional energy input with respect to that provided for stirring. 相似文献
90.
Serena Dato Paolina Crocco Patrizia D’Aquila Francesco de Rango Dina Bellizzi Giuseppina Rose Giuseppe Passarino 《International journal of molecular sciences》2013,14(8):16443-16472
Oxidative stress is both the cause and consequence of impaired functional homeostasis characterizing human aging. The worsening efficiency of stress response with age represents a health risk and leads to the onset and accrual of major age-related diseases. In contrast, centenarians seem to have evolved conservative stress response mechanisms, probably derived from a combination of a diet rich in natural antioxidants, an active lifestyle and a favorable genetic background, particularly rich in genetic variants able to counteract the stress overload at the level of both nuclear and mitochondrial DNA. The integration of these factors could allow centenarians to maintain moderate levels of free radicals that exert beneficial signaling and modulator effects on cellular metabolism. Considering the hot debate on the efficacy of antioxidant supplementation in promoting healthy aging, in this review we gathered the existing information regarding genetic variability and lifestyle factors which potentially modulate the stress response at old age. Evidence reported here suggests that the integration of lifestyle factors (moderate physical activity and healthy nutrition) and genetic background could shift the balance in favor of the antioxidant cellular machinery by activating appropriate defense mechanisms in response to exceeding external and internal stress levels, and thus possibly achieving the prospect of living a longer life. 相似文献