121 research outputs found

    Impact of physical activity on bone health: biochemical and cellular mechanisms

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    L’esercizio fisico porta svariati benefici all’intero organismo. Tra questi un ruolo particolarmente importante è quello legato al mantenimento della funzionalità ossea. L’attività fisica esplica i suoi effetti sull’osso attraverso svariati meccanismi, e nel nostro lavoro abbiamo valutato alcuni aspetti cellulari e biochimici che stanno alla base degli effetti dell’esercizio sull’osso. In particolare ci siamo occupati dell’azione della citochina sclerostina, un modulatore negativo della crescita ossea, partendo dall’osservazione che giovani ginnaste praticanti ginnastica ritmica mostravano elevati livelli circolanti di sclerostina nonostante parametri di densità minerale ossea significativamente più alti rispetto ai controlli. La ginnastica ritmica infatti è un’attività di impatto che notoriamente favorisce una buona ossificazione. Questi dati sono stati confermati anche in un follow-up a un anno di distanza, quando l’aumento della sclerostina è stato drammatico per il gruppo che praticava ginnastica ritmica. Per approfondire a livello cellulare alcuni aspetti biochimici legati all’azione della sclerostina, abbiamo utilizzato un modello in vitro rappresentato da cellule SaOS2, che sono cellule osteogeniche con diverse caratteristiche degli osteoblasti. Abbiamo evidenziato che la sclerostina inibisce il processo di mineralizzazione e causa apoptosi con aumento dell’attività delle caspasi. L’effetto proapoptotico della sclerostina era però inibito dal trattamento con molecole in grado di stimolare l’autofagia, come la poliamina naturale spermidina, indicando anche un possibile ruolo modulatore delle poliamine sull’azione biologica della sclerostina. Inoltre, anche l’attivazione della proteina cinasi attivata da AMP (AMPK) o della deacetilasi SIRT1, eventi correlati all’esercizio fisico, portavano all’inibizione dell’effetto proapoptotico della sclerostina in associazione con l’attivazione di autofagia. Questi dati suggeriscono alcuni meccanismi attraverso cui l’esercizio può influire su osteogenesi e rimodellamento osseo, processi fondamentali per garantire la salute dell’osso durante l’intero arco della vita.Exercise is a key lifestyle approach to optimize bone health. Physical activity can influence bone physiology through many ways. We studied at cellular level some biochemical mechanisms involved in the action of sclerostin, a cytokine that negatively affect bone growth and metabolism. This study started from the observation that young rhythmic gymnasts have high levels of circulating sclerostin, in spite of a high degree of bone mineralization, suggesting that exercise is able to neutralize the negative effect of sclerostin on bone growth. In order to study some biochemical aspects of sclerostin, we used SaOS2 osteosarcoma cells, which are osteogenic cells with osteoblastic characteristics. In this experimental model we observed that sclerostin inhibited mineralization and induced apoptosis with caspase activation. The proapoptotic effect of sclerostin was inhibited by inducers of autophagy such as the natural polyamine spermidine, suggesting a possible link between sclerostin and polyamines. Furthermore, also activation of AMP activated protein kinase (AMPK) or of the SIRT1 deacetylase led to protection against sclerostin-induced apoptosis. Interestingly, AMPK and SIRT1 are both associated to exercise. These data suggest a new mechanism whereby fisical exercise can modulate osteogenesis and bone remodelling, that are important pocesses associated to bone health

    Static quantities of the W boson in the SU_L(3) X U_X(1) model with right-handed neutrinos

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    The static electromagnetic properties of the WW boson, Δκ\Delta \kappa and ΔQ\Delta Q, are calculated in the SU_L(3)} \times U_X(1) model with right-handed neutrinos. The new contributions from this model arise from the gauge and scalar sectors. In the gauge sector there is a new contribution from a complex neutral gauge boson Y0Y^0 and a singly-charged gauge boson Y±Y^\pm. The mass of these gauge bosons, called bileptons, is expected to be in the range of a few hundreds of GeV according to the current bounds from experimental data. If the bilepton masses are of the order of 200 GeV, the size of their contribution is similar to that obtained in other weakly coupled theories. However the contributions to both ΔQ\Delta Q and Δκ\Delta \kappa are negligible for very heavy or degenerate bileptons. As for the scalar sector, an scenario is examined in which the contribution to the WW form factors is identical to that of a two-Higgs-doublet model. It is found that this sector would not give large corrections to Δκ\Delta \kappa and ΔQ\Delta Q.Comment: New material included. Final version to apppear in Physical Review

    Granulocytes-Rich Thrombi in Cerebral Large Vessel Occlusion Are Associated with Increased Stiffness and Poorer Revascularization Outcomes

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    Acute stroke; Flow cytometry; Mechanical thrombectomyIctus agut; Citometria de flux; Trombectomia mecànicaIctus agudo; Citometría de flujo; Trombectomía mecánicaWe aim to identify a profile of intracranial thrombus resistant to recanalization by mechanical thrombectomy (MT) in acute stroke treatment. The first extracted clot of each MT was analyzed by flow cytometry obtaining the composition of the main leukocyte populations: granulocytes, monocytes, and lymphocytes. Demographics, reperfusion treatment, and grade of recanalization were registered. MT failure (MTF) was defined as final thrombolysis in cerebral infarction score IIa or lower and/or need of permanent intracranial stenting as a rescue therapy. To explore the relationship between stiffness of intracranial clots and cellular composition, unconfined compression tests were performed in other cohorts of cases. Thrombi obtained in 225 patients were analyzed. MTF were observed in 30 cases (13%). MTF was associated with atherosclerosis etiology (33.3% vs. 15.9%; p = 0.021) and higher number of passes (3 vs. 2; p < 0.001). Clot analysis of MTF showed higher percentage of granulocytes [82.46 vs. 68.90% p < 0.001] and lower percentage of monocytes [9.18% vs.17.34%, p < 0.001] in comparison to successful MT cases. The proportion of clot granulocytes (aOR 1.07; 95% CI 1.01–1.14) remained an independent marker of MTF. Among thirty-eight clots mechanically tested, there was a positive correlation between granulocyte proportion and thrombi stiffness (Pearson’s r = 0.35, p = 0.032), with a median clot stiffness of 30.2 (IQR, 18.9–42.7) kPa. Granulocytes-rich thrombi are harder to capture by mechanical thrombectomy due to increased stiffness, so a proportion of intracranial granulocytes might be useful to guide personalized endovascular procedures in acute stroke treatment.Open Access Funding provided by Universitat Autonoma de Barcelona. This work was supported by “Project 355/C/2017, Fundació La Marató de TV3 in Strokes and Traumatic Spinal Cord and Brain Injury, 2017 Call of Projects.

    Granulocytes-Rich Thrombi in Cerebral Large Vessel Occlusion Are Associated with Increased Stiffness and Poorer Revascularization Outcomes

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    Altres ajuts: acords transformatius de la UABWe aim to identify a profile of intracranial thrombus resistant to recanalization by mechanical thrombectomy (MT) in acute stroke treatment. The first extracted clot of each MT was analyzed by flow cytometry obtaining the composition of the main leukocyte populations: granulocytes, monocytes, and lymphocytes. Demographics, reperfusion treatment, and grade of recanalization were registered. MT failure (MTF) was defined as final thrombolysis in cerebral infarction score IIa or lower and/or need of permanent intracranial stenting as a rescue therapy. To explore the relationship between stiffness of intracranial clots and cellular composition, unconfined compression tests were performed in other cohorts of cases. Thrombi obtained in 225 patients were analyzed. MTF were observed in 30 cases (13%). MTF was associated with atherosclerosis etiology (33.3% vs. 15.9%; p = 0.021) and higher number of passes (3 vs. 2; p < 0.001). Clot analysis of MTF showed higher percentage of granulocytes [82.46 vs. 68.90% p < 0.001] and lower percentage of monocytes [9.18% vs.17.34%, p < 0.001] in comparison to successful MT cases. The proportion of clot granulocytes (aOR 1.07; 95% CI 1.01-1.14) remained an independent marker of MTF. Among thirty-eight clots mechanically tested, there was a positive correlation between granulocyte proportion and thrombi stiffness (Pearson's r = 0.35, p = 0.032), with a median clot stiffness of 30.2 (IQR, 18.9-42.7) kPa. Granulocytes-rich thrombi are harder to capture by mechanical thrombectomy due to increased stiffness, so a proportion of intracranial granulocytes might be useful to guide personalized endovascular procedures in acute stroke treatment. Supplementary Information: The online version contains supplementary material available at 10.1007/s13311-023-01385-1

    A Novel Pathway of TEF Regulation Mediated by MicroRNA-125b Contributes to the Control of Actin Distribution and Cell Shape in Fibroblasts

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    BACKGROUND: Thyrotroph embryonic factor (TEF), a member of the PAR bZIP family of transcriptional regulators, has been involved in neurotransmitter homeostasis, amino acid metabolism, and regulation of apoptotic proteins. In spite of its relevance, nothing is known about the regulation of TEF. PRINCIPAL FINDINGS: p53-dependent genotoxic agents have been shown to be much more harmful for PAR bZIP-deficient mice as compared to wild type animals. Here we demonstrate that TEF expression is controlled by p53 through upregulation of microRNA-125b, as determined by both regulating the activity of p53 and transfecting cells with microRNA-125b precursors. We also describe a novel role for TEF in controlling actin distribution and cell shape in mouse fibroblasts. Lack of TEF is accompanied by dramatic increase of cell area and decrease of elongation (bipolarity) and dispersion (multipolarity). Staining of actin cytoskeleton also showed that TEF (-/-) cells are characterized by appearance of circumferential actin bundles and disappearance of straight fibers. Interestingly, transfection of TEF (-/-) fibroblasts with TEF induced a wild type-like phenotype. Consistent with our previous findings, transfection of wild type fibroblasts with miR-125b promoted a TEF (-/-)-like phenotype, and a similar but weaker effect was observed following exogenous expression of p53. CONCLUSIONS/SIGNIFICANCE: These findings provide the first evidence of TEF regulation, through a miR-125b-mediated pathway, and describes a novel role of TEF in the maintenance of cell shape in fibroblasts

    A Mycobacterium leprae Hsp65 Mutant as a Candidate for Mitigating Lupus Aggravation in Mice

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    Hsp60 is an abundant and highly conserved family of intracellular molecules. Increased levels of this family of proteins have been observed in the extracellular compartment in chronic inflammation. Administration of M. leprae Hsp65 [WT] in [NZBxNZW]F1 mice accelerates the Systemic Lupus Erythematosus [SLE] progression whereas the point mutated K409A Hsp65 protein delays the disease. Here, the biological effects of M. leprae Hsp65 Leader pep and K409A pep synthetic peptides, which cover residues 352–371, are presented. Peptides had immunomodulatory effects similar to that observed with their respective proteins on survival and the combined administration of K409A+Leader pep or K409A pep+WT showed that the mutant forms were able to inhibit the deleterious effect of WT on mortality, indicating the neutralizing potential of the mutant molecules in SLE progression. Molecular modeling showed that replacing Lysine by Alanine affects the electrostatic potential of the 352–371 region. The number of interactions observed for WT is much higher than for Hsp65 K409A and mouse Hsp60. The immunomodulatory effects of the point-mutated protein and peptide occurred regardless of the catalytic activity. These findings may be related to the lack of effect on survival when F1 mice were inoculated with Hsp60 or K409A pep. Our findings indicate the use of point-mutated Hsp65 molecules, such as the K409A protein and its corresponding peptide, that may minimize or delay the onset of SLE, representing a new approach to the treatment of autoimmune diseases

    Insight on the fundamentals of advanced oxidation processes. Role and review of the determination methods of reactive oxygen species

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    Advanced oxidation processes (AOPs) have known increased application to treat wastewaters containing recalcitrant compounds that are hardly degraded by conventional technologies. AOPs are characterized by the formation of strong oxidants such as hydroxyl radicals, superoxide anions, hydroperoxyl radicals and singlet oxygen, which react with the contaminant, contributing to its degradation. This paper provides an overview of the determination methods of reactive oxygen species, ROS, in the application of AOPs; the methods developed in the available literature for the detection and quantification of ROS are reviewed as a first step in the assessment and detailed description of the mechanisms involved in the oxidation reactions, focusing on the critical analysis of the main strengths and weaknesses presented by the probe molecules employed in the evaluated studies.This research was supported by the Ministry of Economy and Competitiveness (MINECO/SPAIN) and European Regional Development Fund (ERDF) under the project CTQ2011-25262

    Geolocation with respect to persona privacy for the Allergy Diary app - a MASK study

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    Background: Collecting data on the localization of users is a key issue for the MASK (Mobile Airways Sentinel network: the Allergy Diary) App. Data anonymization is a method of sanitization for privacy. The European Commission's Article 29 Working Party stated that geolocation information is personal data. To assess geolocation using the MASK method and to compare two anonymization methods in the MASK database to find an optimal privacy method. Methods: Geolocation was studied for all people who used the Allergy Diary App from December 2015 to November 2017 and who reported medical outcomes. Two different anonymization methods have been evaluated: Noise addition (randomization) and k-anonymity (generalization). Results: Ninety-three thousand one hundred and sixteen days of VAS were collected from 8535 users and 54,500 (58. 5%) were geolocalized, corresponding to 5428 users. Noise addition was found to be less accurate than k-anonymity using MASK data to protect the users' life privacy. Discussion: k-anonymity is an acceptable method for the anonymization of MASK data and results can be used for other databases.Peer reviewe

    Risk factors associated with adverse fetal outcomes in pregnancies affected by Coronavirus disease 2019 (COVID-19): a secondary analysis of the WAPM study on COVID-19.

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    Objectives To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Methods Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratory-confirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Results Mean gestational age at diagnosis was 30.6+/-9.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; pPeer reviewe
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