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71.
Raffaele De Vita Delia Cavallo Luigi Raganella Patrizia Eleuteri Maria G. Grollino Alberto Calugi 《Bioelectromagnetics》1995,16(5):330-334
Flow cytometry (FCM) was performed to monitor the cellular effects of extremely-low-frequency magnetic field on mouse spermatogenesis. Groups of five male hybrid F1 mice aged 8–10 weeks were exposed to 50 Hz magnetic field. The strength of the magnetic field was 1.7 mT. Exposure times of 2 and 4 h were chosen. FCM measurements were performed 7, 14, 21, 28, 35, and 42 days after treatment. For each experimental point, a sham-treated group was used as a control. The possible effects were studied by analyzing the DNA content distribution of the different cell types involved in spermatogenesis and using the elongated spermatids as the reference population. The relative frequencies of the various testicular cell types were calculated using specific software. In groups exposed for 2 h, no effects were observed. In groups exposed for 4 h, a statistically significant (P < 0.001) decrease in elongated spermatids was observed at 28 days after treatment. This change suggests a possible cytotoxic and/or cytostatic effect on differentiating spermatogonia. However, further studies are being carried out to investigate the effects of longer exposure times. © 1995 Wiley-Liss, Inc. 相似文献
72.
Luigi Montibeller Li Yi Tan Joo Kyung Kim Praveen Paul Jacqueline de Belleroche 《Journal of cellular and molecular medicine》2020,24(11):6055-6069
Amyotrophic lateral sclerosis (ALS) is a disorder that affects motor neurons in motor cortex and spinal cord, and the degeneration of both neuronal populations is a critical feature of the disease. Abnormalities in protein homeostasis (proteostasis) are well established in ALS. However, they have been investigated mostly in spinal cord but less so in motor cortex. Herein, we monitored the unfolded protein (UPR) and heat shock response (HSR), two major proteostasis regulatory pathways, in human post-mortem tissue derived from the motor cortex of sporadic ALS (SALS) and compared them to those occurring in spinal cord. Although the UPR was activated in both tissues, specific expression of select UPR target genes, such as PDIs, was observed in motor cortex of SALS cases strongly correlating with oligodendrocyte markers. Moreover, we found that endoplasmic reticulum-associated degradation (ERAD) and HSR genes, which were activated predominately in spinal cord, correlated with the expression of neuronal markers. Our results indicate that proteostasis is strongly and selectively activated in SALS motor cortex and spinal cord where subsets of these genes are associated with specific cell type. This study expands our understanding of convergent molecular mechanisms occurring in motor cortex and spinal cord and highlights cell type–specific contributions. 相似文献
73.
Fatemeh Adelnia Ceereena Ubaida‐Mohien Ruin Moaddel Michelle Shardell Alexey Lyashkov Kenneth W. Fishbein Miguel A. Aon Richard G. Spencer Luigi Ferrucci 《Aging cell》2020,19(4)
Adequate support of energy for biological activities and during fluctuation of energetic demand is crucial for healthy aging; however, mechanisms for energy decline as well as compensatory mechanisms that counteract such decline remain unclear. We conducted a discovery proteomic study of skeletal muscle in 57 healthy adults (22 women and 35 men; aged 23–87 years) to identify proteins overrepresented and underrepresented with better muscle oxidative capacity, a robust measure of in vivo mitochondrial function, independent of age, sex, and physical activity. Muscle oxidative capacity was assessed by 31P magnetic resonance spectroscopy postexercise phosphocreatine (PCr) recovery time (τPCr) in the vastus lateralis muscle, with smaller τPCr values reflecting better oxidative capacity. Of the 4,300 proteins quantified by LC‐MS in muscle biopsies, 253 were significantly overrepresented with better muscle oxidative capacity. Enrichment analysis revealed three major protein clusters: (a) proteins involved in key energetic mitochondrial functions especially complex I of the electron transport chain, tricarboxylic acid (TCA) cycle, fatty acid oxidation, and mitochondrial ABC transporters; (b) spliceosome proteins that regulate mRNA alternative splicing machinery, and (c) proteins involved in translation within mitochondria. Our findings suggest that alternative splicing and mechanisms that modulate mitochondrial protein synthesis are central features of the molecular mechanisms aimed at maintaining mitochondrial function in the face of impairment. Whether these mechanisms are compensatory attempt to counteract the effect of aging on mitochondrial function should be further tested in longitudinal studies. 相似文献
74.
Michael J. D'Occhio Giuseppe Campanile Luigi Zicarelli Jos A. Visintin Pietro S. Baruselli 《Molecular reproduction and development》2020,87(2):206-222
Cell–cell adhesion molecules have critically important roles in the early events of reproduction including gamete transport, sperm–oocyte interaction, embryonic development, and implantation. Major adhesion molecules involved in reproduction include cadherins, integrins, and disintegrin and metalloprotease domain‐containing (ADAM) proteins. ADAMs on the surface of sperm adhere to integrins on the oocyte in the initial stages of sperm–oocyte interaction and fusion. Cadherins act in early embryos to organize the inner cell mass and trophectoderm. The trophoblast and uterine endometrial epithelium variously express cadherins, integrins, trophinin, and selectin, which achieve apposition and attachment between the elongating conceptus and uterine epithelium before implantation. An overview of the major cell–cell adhesion molecules is presented and this is followed by examples of how adhesion molecules help shape early reproductive events. The argument is made that a deeper understanding of adhesion molecules and reproduction will inform new strategies that improve embryo survival and increase the efficiency of natural mating and assisted breeding in cattle. 相似文献
75.
David S. Goodsell Christine Zardecki Luigi Di Costanzo Jose M. Duarte Brian P. Hudson Irina Persikova Joan Segura Chenghua Shao Maria Voigt John D. Westbrook Jasmine Y. Young Stephen K. Burley 《Protein science : a publication of the Protein Society》2020,29(1):52-65
Analyses of publicly available structural data reveal interesting insights into the impact of the three‐dimensional (3D) structures of protein targets important for discovery of new drugs (e.g., G‐protein‐coupled receptors, voltage‐gated ion channels, ligand‐gated ion channels, transporters, and E3 ubiquitin ligases). The Protein Data Bank (PDB) archive currently holds > 155,000 atomic‐level 3D structures of biomolecules experimentally determined using crystallography, nuclear magnetic resonance spectroscopy, and electron microscopy. The PDB was established in 1971 as the first open‐access, digital‐data resource in biology, and is now managed by the Worldwide PDB partnership (wwPDB; wwPDB.org ). US PDB operations are the responsibility of the Research Collaboratory for Structural Bioinformatics PDB (RCSB PDB). The RCSB PDB serves millions of RCSB.org users worldwide by delivering PDB data integrated with ~40 external biodata resources, providing rich structural views of fundamental biology, biomedicine, and energy sciences. Recently published work showed that the PDB archival holdings facilitated discovery of ~90% of the 210 new drugs approved by the US Food and Drug Administration 2010–2016. We review user‐driven development of RCSB PDB services, examine growth of the PDB archive in terms of size and complexity, and present examples and opportunities for structure‐guided drug discovery for challenging targets (e.g., integral membrane proteins). 相似文献
76.
Ventura Luigi Gnetti Letizia Rossi Maurizio Tiseo Marcello Giordano Giovanna Corradi Massimo Silva Mario Milanese Gianluca Minari Roberta Leonetti Alessandro Cattadori Sara Ampollini Luca Carbognani Paolo Mozzoni Paola 《Molecular biology reports》2021,48(4):3485-3494
Molecular Biology Reports - Benign metastasizing leiomyoma (BML) is a rare disease characterized by extrauterine benign leiomyomatosis in patients with a previous or concomitant history of uterine... 相似文献
77.
Mayarling Francisca Troncoso Jafet Ortiz-Quintero Valeria Garrido-Moreno Fernanda Sanhueza-Olivares Alejandra Guerrero-Moncayo Mario Chiong Pablo F. Castro Lorena García Luigi Gabrielli Ramón Corbalán Luis Garrido-Olivares Sergio Lavandero 《生物化学与生物物理学报:疾病的分子基础》2021,1867(9):166170
The vascular cellular adhesion molecule-1 (VCAM-1) is a protein that canonically participates in the adhesion and transmigration of leukocytes to the interstitium during inflammation. VCAM-1 expression, together with soluble VCAM-1 (sVCAM-1) induced by the shedding of VCAM-1 by metalloproteinases, have been proposed as biomarkers in immunological diseases, cancer, autoimmune myocarditis, and as predictors of mortality and morbidity in patients with chronic heart failure (HF), endothelial injury in patients with coronary artery disease, and arrhythmias. This revision aims to discuss the role of sVCAM-1 as a biomarker to predict the occurrence, development, and preservation of cardiovascular disease. 相似文献
78.
Gabriella Galatà Andrés C. García-Montero Thomas Kristensen Ahmed A.Z. Dawoud Javier I. Muñoz-González Manja Meggendorfer Paola Guglielmelli Yvette Hoade Ivan Alvarez-Twose Christian Gieger Konstantin Strauch Luigi Ferrucci Toshiko Tanaka Stefania Bandinelli Theresia M. Schnurr Torsten Haferlach Sigurd Broesby-Olsen Hanne Vestergaard William J. Tapper 《American journal of human genetics》2021,108(2):284-294
79.
Abstract OXIDATION PATHWAYS OF EXTRAMITOCHONDRIAL PIRIDINE COENZYMES. I. - ON THE « IN VIVO » EFFICIENCY OF THE ASCORBATE-DEYHDROASCORBATE SYSTEM. — An evaluation of the efficiency in vivo of the AA-DHA couple as an electron carrier system has been attempted, by measuring after short time of anaerobiosis the rate of the increase of AA and of the dicrease of DHA in etiolated pea internode segments and in potato tuber disks. The changes of reduced glutathione (GSH) contents as induced by anaerobiosis or by the addition of DHA to the incubation medium were also followed. In the pea segments anaerobiosis induced a significant increase of AA and a corresponding decrease of DHA. These changes were almost completed after 10 minutes from starting anaerobiosis. The value (extrapolated to 0 time) of the initial rate of DHA desappearance under anaerobiosis was taken as representing the rate of DHA reduction to AA « in vivo », under aerobic conditions. As this rate — in a steady state situation — corresponds to that of the inverse process of oxidation of AA to DHA, this value should give and indication on the « in vivo » efficiency of the AA-DHA system as an electron carrier in respiration. As some AA was probably reoxidized to DHA in the very short period required to kill the tissue, the value of the AA DHA turnover thus calculated is probably somewhat lower than the real one. According to the present work, the oxidative turnover of the AA-DHA system would results of 0,7 micromoles/g. fr. weght/h. for the pea internode tissues and of 0,9 micromoles/g. fr. weght?h for the potato tuber (aged disks). These values would account for 5% of total oxygen uptake, in the former, and for 3% in the latter material. The very high AA/DHA ratio usually prevailing in living cells suggests that the contents in DHA (and thus the activity of the AA oxidizing systems) is a limiting factor for the efficiency of the AA-DHA system as an electron carrier. This view is supported also by experiments in which DHA (at pH 5) was fed to pea internode segments and to potato tuber disks : as the presence of DHA into the medium induced — under anaerobiotic conditions — a rapid increase of the level of AA in both types of materials. In aerobiosis uptake and reduction of DHA to AA was evident in the potato tuber tissue, while it appeared very scarce in the pea internodes. As an interpretation of this behaviour it is suggested that, in aerobiosis, the very active and probably surface localized ascorbic acid oxidase of the pea tissue re-oxidises the AA formed from reduction of the DHA fed; an accumulation of DHA into the cells would follow, and this excess of DHA would inhibit the enzyme GSH-DHA reductase. This enzyme, in fact, appears, from « in vitro » experiments, to be strongly inhibited by DHA when the DHA/GSH ratio becomes higher than 1. On the other hand, the same hypothesis is also supported by the finding that the addition of DHA to the medium induces a significant drop in the GSH level (probably due to its oxidation to GSSG) only under those conditions in which DHA is absorbed and reduced to AA; that is, in the pea internodes, under anaerobiosis, and in the potato disks, under both anaerobiosis and aerobiosis. These results are also taken as confirming the indication from the enzymatic data that GSH is acting, in vivo as a reducing agent for DHA. The results of this investigation are thus interpred as showing that a comparatively small, but by no means negligeable fraction of respiration is mediated, in higher plant tissues such as those of the pea stem and the potato tuber, by and electron transfer system including glutathione and the ascorbate-dehydroascorbate couple. The efficiency of this system in the materials investigated appears to account for 3–5% of the total 02 uptake (minimum value). As enzyme systems transferring electrons from TPNH to ox. glutathione are widely distributed and generally very active in higher plant tissues, it is suggested that the sequence TPNH-GSH-AA/DHA - O2 is probably of considerable importance in mediating the reoxidation of extramitochondrial trophosphoridine nucleotide and thus in permitting the operation of the TPN requiring pentose phosphate pathway of respiration. 相似文献
80.