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991.
Shuwen Shan Fangzheng Xu Marc Hirschfeld Claudia Herrmann Martin Schulze Ahmad Reza Sharifi Michael Hoelker Bertram Brenig 《International journal of molecular sciences》2022,23(14)
Recently it was shown that a specific form of male infertility in Holstein cattle was caused by a nonsense variant in the α/β-hydrolase domain-containing 16B (ABHD16B) gene resulting in a protein truncation at amino acid position 218 (p.218Q*) and loss of function. Lipidomics showed that the absence of ABHD16B influenced the content of phosphatidylcholine (PC), ceramide (Cer), diacylglycerol (DAG), and sphingomyelin (SM) in variant carrier sperm membranes. However, the exact cause of infertility in affected sires has remained unclear until now. To elucidate the cause of infertility, we analyzed (i) standard sperm parameters (i.e., total sperm number, morphological intact sperm, total sperm motility), (ii) in vitro fertilizability and effects on early embryonic development, and (iii) sperm survival rates (i.e., capacitation time). The affected spermatozoa showed no changes in the usual sperm parameters and were also capable of fertilization in vitro. Furthermore, the absence of ABHD16B did not affect early embryonic development. Based on these results, it was concluded that the affected spermatozoa appeared to be fertilizable per se. Consequently, the actual cause of the inability to fertilize could only be due to a time- and/or place-dependent process after artificial insemination and before fertilization. A process fundamental to the ability to fertilize after insemination is capacitation. Capacitation is a biochemical maturation process that spermatozoa undergo in the female genital tract and is inevitable for the successful fertilization of the oocyte. It is known that the presence and concentration of certain sperm membrane lipids are essential for the correct course of capacitation. However, precisely these lipids are absent in the membrane of spermatozoa affected by the ABHD16B truncation. Since all other causes of fertilization inability were excluded in the previous experiments, consequently, the only remaining hypothesis was that the loss of function of ABHD16B leads to a capacitation disruption. We were able to show that heterozygous and homozygous affected spermatozoa exhibit premature capacitation and therefore decay before fertilization. This effect of the loss of function of ABHD16B has not been described before and our studies now revealed why sires harboring the variant in the ABHD16B gene are infertile. 相似文献
992.
María Elena Soto Giovanny Fuentevilla-lvarez Adrin Palacios-Chavarría Rafael Ricardo Valdez Vzquez Hctor Herrera-Bello Lidia Moreno-Castaeda Yazmín Estela Torres-Paz Nadia Janet Gonzlez-Moyotl Idalia Prez-Torres Alfredo Aisa-Alvarez Linaloe Manzano-Pech Israel Prez-Torres Claudia Huesca-Gmez Ricardo Gamboa 《International journal of molecular sciences》2023,24(1)
In patients with severe pneumonia due to COVID-19, the deregulation of oxidative stress is present. Nuclear erythroid factor 2 (NRF2) is regulated by KEAP1, and NRF2 regulates the expression of genes such as NFE2L2-KEAP1, which are involved in cellular defense against oxidative stress. In this study, we analyzed the participation of the polymorphisms of NFE2L2 and KEAP1 genes in the mechanisms of damage in lung disease patients with SARS-CoV-2 infection. Patients with COVID-19 and a control group were included. Organ dysfunction was evaluated using SOFA. SARS-CoV-2 infection was confirmed and classified as moderate or severe by ventilatory status and by the Berlin criteria for acute respiratory distress syndrome. SNPs in the gene locus for NFE2L2, rs2364723C>G, and KEAP1, rs9676881A>G, and rs34197572C>T were determined by qPCR. We analyzed 110 individuals with SARS-CoV-2 infection: 51 with severe evolution and 59 with moderate evolution. We also analyzed 111 controls. Significant differences were found for rs2364723 allele G in severe cases vs. controls (p = 0.02); for the rs9676881 allele G in moderate cases vs. controls (p = 0.04); for the rs34197572 allele T in severe cases vs. controls (p = 0.001); and in severe vs. moderate cases (p = 0.004). Our results showed that NFE2L2 rs2364723C>G allele G had a protective effect against severe COVID-19, while KEAP1 rs9676881A>G allele G and rs34197572C>T minor allele T were associated with more aggressive stages of COVID-19. 相似文献
993.
Claudia Maria Hattinger Iris Chiara Salaroglio Leonardo Fantoni Martina Godel Chiara Casotti Joanna Kopecka Katia Scotlandi Toni Ibrahim Chiara Riganti Massimo Serra 《International journal of molecular sciences》2023,24(1)
Improving the prognosis and cure rate of HGOSs (high-grade osteosarcomas) is an absolute need. Immune-based treatment approaches have been increasingly taken into consideration, in particular for metastatic, relapsed and refractory HGOS patients, to ameliorate the clinical results currently achieved. This review is intended to give an overview on the immunotherapeutic treatments targeting, counteracting or exploiting the different immune cell compartments that are present in the HGOS tumor microenvironment. The principle at the basis of these strategies and the possible mechanisms that HGOS cells may use to escape these treatments are presented and discussed. Finally, a list of the currently ongoing immune-based trials in HGOS is provided, together with the results that have been obtained in recently completed clinical studies. The different strategies that are presently under investigation, which are generally aimed at abrogating the immune evasion of HGOS cells, will hopefully help to indicate new treatment protocols, leading to an improvement in the prognosis of patients with this tumor. 相似文献
994.
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
995.
996.
Pooja Joshi Luisa Benussi Roberto Furlan Roberta Ghidoni Claudia Verderio 《International journal of molecular sciences》2015,16(3):4800-4813
The intercellular transfer of amyloid-β (Aβ) and tau proteins has received increasing attention in Alzheimer’s disease (AD). Among other transfer modes, Aβ and tau dissemination has been suggested to occur through release of Extracellular Vesicles (EVs), which may facilitate delivery of pathogenic proteins over large distances. Recent evidence indicates that EVs carry on their surface, specific molecules which bind to extracellular Aβ, opening the possibility that EVs may also influence Aβ assembly and synaptotoxicity. In this review we focus on studies which investigated the impact of EVs in Aβ-mediated neurodegeneration and showed either detrimental or protective role for EVs in the pathology. 相似文献
997.
998.
Claudia E. Flores De la Rosa Martin Herrera Trejo Manuel Castro Román Eddy Alfaro López 《Journal of Materials Engineering and Performance》2016,25(7):2596-2603
The shot peening is used in the leaf springs manufacturing process for producing a compressive residual stress field (CRSF) at and near the surface that improves the fatigue resistance. The resulting CRSF is influenced by the surface ferrite thickness associated with the decarburization. Hence, this work aims to extend the knowledge on the influence of the decarburization on the CRSF for the given shot peening conditions. A study on the laboratory scale was conducted for an SAE 5160 steel grade used in the automotive industry. Next, specimens with different decarburization depths were treated using industrial shot peening, and the resulting CRSF was characterized. The CRSF was found to be influenced by the decarburization depth. It is assumed that the elastic deformation mechanism is predominant at low decarburization depths, followed by a zone in which both the elastic and plastic deformation have competing mechanisms that contribute to the CRSF, and at higher decarburization depths, the dominant mechanism is plastic deformation. The values for σsrs and σmcrs decrease as the decarburized depth increases, and suitable CRSFs were obtained below a decarburization depth of 120 µm in industrial leaves. Furthermore, the prediction based on expressions correlating the measured variables was good in these leaves. 相似文献
999.
1000.
Ernesto Enciso-Contreras Juan Gabriel Barbosa-Saldafia Jose Alfredo Jimenez-Bemal Claudia del Carmen Gutierrez-Torres 《机械工程与自动化:英文版》2014,(7):565-574
The present work describes software SOLEEC (copyright 03-2012-070510302900-01 Mexico), a numerical tool for PTC (parabolic trough collector) designing. Software SOLEEC is divided into two main parts. The first one allows solar resource assessment for a specific place on the Earth. The computation and assessment can be done for a specific day on the year, for one specific month and the monthly averages along the year. The last one gives annual charts such as: solar constant, Earth declination, insolation hours, and sunrise and sunset hours. The second part has four different execution options for PTC designing, that is, using options one and two user can get five different designs based on receiver outer diameter evaluating solar radiation data along the full year or only one solar radiation value (monthly), on the other hand options three and four were developed to compute the thermal evaluation for an operating collector for twelve solar radiation values (annually) or a specific month computation, respectively. 相似文献