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61.
Massimo Venditti Marouane Chemek Sergio Minucci Imed Messaoudi 《Molecular reproduction and development》2020,87(5):565-573
During the differentiation of the male gamete, there is a massive remodeling in the shape and architecture of all the cells of the seminiferous epithelium. The cytoskeleton, as well as many associated proteins with it, plays a pivotal role in this process. The testis is particularly susceptible to environmental pollutant, which can lead to injury and impairment of normal spermatozoa production. Cadmium (Cd) is one of the major chemical environmental toxicants in economically developed countries. Food and cigarettes are the main sources of exposure to this element. Here, the protective role of zinc (Zn) to prevent the testicular toxicity in male adult rats after prenatal and during lactation exposure to Cd has been assessed. Altered testicular histology at the interstitial and germinal levels was found, whereas Zn supply completely corrected Cd toxicity. Moreover, the effects of these metals on the testicular expression and localization of the protease prolyl endopeptidase (PREP) were evaluated. Interestingly, the results showed an increase of PREP messenger RNA and protein. Data were corroborated by immunofluorescence. This study raises the possibility of using PREP as a new fertility marker. 相似文献
62.
Blanca Domenech‐Ximenos Victor Cuba Pepus Daunis‐i‐Estadella Santiago Thi‐Henestrosa Francisco Jaldo Carles Biarnes Xavier Molina Gemma Xifra Wifredo Ricart Anton Bardera Imma Boada Marco Essig Salvador Pedraza Massimo Federici Jos Manuel Fernndez‐Real Josep Puig 《Obesity (Silver Spring, Md.)》2020,28(9):1663-1670
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Mario Gimona Maria Felice Brizzi Andre Boon Hwa Choo Massimo Dominici Sean M. Davidson Johannes Grillari Dirk M. Hermann Andrew F. Hill Dominique de Kleijn Ruenn Chai Lai Charles P. Lai Rebecca Lim Marta Monguió-Tortajada Maurizio Muraca Takahiro Ochiya Luis A. Ortiz Wei Seong Toh Yong Weon Yi Sai Kiang Lim 《Cytotherapy》2021,23(5):373-380
Mesenchymal stromal/stem cells (MSCs) have been widely tested against many diseases, with more than 1000 registered clinical trials worldwide. Despite many setbacks, MSCs have been approved for the treatment of graft-versus-host disease and Crohn disease. However, it is increasingly clear that MSCs exert their therapeutic functions in a paracrine manner through the secretion of small extracellular vesicles (sEVs) of 50–200 nm in diameter. Unlike living cells that can persist long-term, sEVs are non-living and non-replicative and have a transient presence in the body. Their small size also renders sEV preparations highly amenable to sterilization by filtration. Together, acellular MSC-sEV preparations are potentially safer and easier to translate into the clinic than cellular MSC products. Nevertheless, there are inherent challenges in the development of MSC-sEV drug products. MSC-sEVs are products of living cells, and living cells are sensitive to changes in the external microenvironment. Consequently, quality control metrics to measure key identity and potency features of MSC-sEV preparations have to be specified during development of MSC-sEV therapeutics. The authors have previously described quantifiable assays to define the identity of MSC-sEVs. Here the authors discuss requirements for prospective potency assays to predict the therapeutic effectiveness of the drug substance in accordance with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. Although potency assays should ideally reflect the mechanism of action (MoA), this is challenging because the MoA for the reported efficacy of MSC-sEV preparations against multiple diseases of diverse underlying pathology is likely to be complex and different for each disease and difficult to fully elucidate. Nevertheless, robust potency assays could be developed by identifying the EV attribute most relevant to the intended biological activity in EV-mediated therapy and quantifying the EV attribute. Specifically, the authors highlight challenges and mitigation measures to enhance the manufacture of consistent and reproducibly potent sEV preparations, to identify and select the appropriate EV attribute for potency assays despite a complex “work-in-progress” MoA and to develop assays likely to be compliant with regulatory guidance for assay validation. 相似文献
65.
Umberto Nicosia Fabio Massimo Petti Gianluca Perugini Simone D’Orazi Porchetti Eva Sacchi Maria Alessandra Conti 《Ichnos》2013,20(1-2):69-90
A really unexpected finding of sauropod and theropod footprints in southern Latium raises to four the number of the trampled levels recognized in central and southern Italy. After the recent findings in Latest Jurassic and Early, mid and Late Cretaceous carbonate platform deposits of the Periadriatic region, dinosaur footprints seem to provide very important paleogeographic constraints for reconstructing the geodynamic history of the Mediterranean area. The presence of a varied ichnoassociation makes acceptance of the current paleogeographic models concerning the relative and absolute position of the Laziale-Abruzzese-Campano and of Apulian-Dinaric domains during the Late Cretaceous more and more problematic. Dinosaur footprints, combined with other paleontological data, demonstrate that these areas were never completely pulled apart by deep seaways, while frequent or continuous links between them, and to southern and northern mainlands, probably persisted. These data also allowed us to improve our understanding of the timing of the Mesozoic plate motion in this segment of the Western Tethys. 相似文献
66.
Massimo Reverberi Mauro Picardo Alessandra Ricelli Emanuela Camera Corrado Fanelli Anna Adele Fabbri 《Free radical research》2013,47(6):833-841
In order to verify the role played by oxidation in the budding of potato tubers (Solanum tuberosum L. cv. Kennebec), the physiological events occurring below bud at 4°C have been studied for a period of 6 months. The low temperature storage induced an increase in the degree of unsaturation and a decrease in the ratio of saturated/unsaturated fatty acids of membrane polar lipids with a subsequent increase of lipid hydroperoxides (LOOH). Cold stress increased both enzymatic antioxidative activities (superoxide dismutase, SOD, E.C.1.15.1.1; catalase, CAT, E.C. 1.11.1.6), and α-tocopherol levels thus protecting membrane's polyunsaturated lipids. Between 0 and 15 days of storage SOD/CAT ratio, α-tocopherol, LOOH levels and the degree of lipid unsaturation showed strong variations. After 30 to 120/150 days the antioxidative system seemed to reach a homeostasis different from that of time 0, accompanied by a constant increase of indole-3-acetic acid (IAA) after 60 days. The antioxidative system, after 150 days, lost its efficiency while LOOH levels were maintained higher than time 0 and IAA concentration was sufficient to allow sprouting. 相似文献
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Alessandra Vacca Roberta Montisci Pietro Garau Paolo Siotto Matteo Piga Alberto Cauli Massimo Ruscazio Luigi Meloni Sabino Iliceto Alessandro Mathieu 《Arthritis research & therapy》2013,15(1):R8
Introduction
Microcirculation dysfunction is a typical feature of systemic sclerosis (SSc) and represents the earliest abnormality of primary myocardial involvement. We assessed coronary microcirculation status by combining two functional tests in SSc patients and estimating its impact on disease outcome.Methods
Forty-one SSc patients, asymptomatic for coronary artery disease, were tested for coronary flow velocity reserve (CFR) by transthoracic-echo-Doppler with adenosine infusion (A-TTE) and for left ventricular wall motion abnormalities (WMA) by dobutamine stress echocardiography (DSE). Myocardial multi-detector computed tomography (MDCT) enabled the presence of epicardial stenosis, which could interfere with the accuracy of the tests, to be excluded. Patient survival rate was assessed over a 6.7- ± 3.5-year follow-up.Results
Nineteen out of 41 (46%) SSc patients had a reduced CFR (≤2.5) and in 16/41 (39%) a WMA was observed during DSE. Furthermore, 13/41 (32%) patients showed pathological CFR and WMA. An inverse correlation between wall motion score index (WMSI) during DSE and CFR value (r = -0.57, P <0.0001) was observed; in addition, CFR was significantly reduced (2.21 ± 0.38) in patients with WMA as compared to those without (2.94 ± 0.60) (P <0.0001). In 12 patients with abnormal DSE, MDCT was used to exclude macrovasculopathy. During a 6.7- ± 3.5-year follow-up seven patients with abnormal coronary functional tests died of disease-related causes, compared to only one patient with normal tests.Conclusions
A-TTE and DSE tests are useful tools to detect non-invasively pre-clinical microcirculation abnormalities in SSc patients; moreover, abnormal CFR and WMA might be related to a worse disease outcome suggesting a prognostic value of these tests, similar to other myocardial diseases. 相似文献69.
Christian Esposito Massimo Ficco Francesco Palmieri Aniello Castiglione 《Cluster computing》2013,16(4):887-903
Cloud Federation is an emerging computing model where multiple resources from independent Cloud providers are leveraged to create large-scale distributed virtual computing clusters, operating as into a single Cloud organization. This model enables the implementation of environmental diversity for Cloud applications, and overcomes the provisioning and scalability limits of a single Cloud, by introducing minimal additional cost for the Cloud consumer. In such a scenario, it is necessary to leverage on specific networking technologies that enable the effective support of inter-Cloud communication services between Cloud providers. This paper proposes an interconnection solution for Cloud federations based on publish/subscribe services. Moreover, we discuss some fundamental concerns needed to satisfy the inter-Cloud communication requirements in terms of reliability and availability. Finally, we present some experimental results that highlight some key reliability and denial of service vulnerability concerns in this domain. 相似文献
70.
Fulvio Braido Ilaria Baiardini Massimo Sumberesi Francesco Blasi Giorgio Walter Canonica 《Respiratory research》2013,14(1):94