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排序方式: 共有2777条查询结果,搜索用时 15 毫秒
31.
Giovannetti Antonio Susi Gianluca Casti Paola Mencattini Arianna Pusil Sandra López María Eugenia Di Natale Corrado Martinelli Eugenio 《Neural computing & applications》2021,33(21):14651-14667
Neural Computing and Applications - In this paper, we present the novel Deep-MEG approach in which image-based representations of magnetoencephalography (MEG) data are combined with ensemble... 相似文献
32.
Noemi Eiro Sandra Cid Nuria Aguado María Fraile Nagore de Pablo Berta Fernndez Francisco Domínguez Luis O. Gonzlez Francisco J. Vizoso 《International journal of molecular sciences》2021,22(1)
Tumor-infiltrating immune cells phenotype is associated with tumor progression. However, little is known about the phenotype of the peripheral blood mononuclear cells (PBMC) from breast cancer patients. We investigated MMP1 and MMP11 expression in PBMC from breast cancer patients and we analyzed gene expression changes upon their interaction with cancer cells and cancer-associated fibroblasts (CAF). We measured the impact of PBMC on proinflammatory gene expression in breast cancer cells, normal fibroblast (NF), and CAF and the impact on proliferation and invasiveness capacity of breast cancer cells. Gene expression of MMP1 and MMP11 in PBMC from breast cancer patients (n = 54) and control (n = 28); expression of IL1A, IL6, IL17, IFNβ, and NFĸB in breast cancer cell lines (MCF-7 and MDA-MB-231); and, additionally, IL10 and MMP11 in CAF and NF were analyzed by qRT-PCR before and after co-culture. Our results show the existence of a subpopulation of breast cancer patients (25.9%) with very high levels of MMP11 gene expression in PBMC. Also, gene expression of MMP1 and MMP11 increases in PBMC after co-culture with breast cancer cell lines, NF or CAF. PBMC from healthy or breast cancer patients induce an increased proliferation rate on MCF-7 and an increased invasiveness capacity of MDA-MB-231. Finally, we show a differential expression profile of inflammatory genes in NF and CAF when co-cultured with control or breast cancer PBMC. We have observed that MMPs’ expression in PBMC is regulated by the microenvironment, while the expression of inflammatory genes in NF or CAF is differentially regulated by PBMC. These findings confirm the importance of the crosstalk between stromal cells and suggest that PBMC would play a role in promoting aggressive tumor behavior. 相似文献
33.
Neuroprotective Effects of Testosterone in the Hypothalamus of an Animal Model of Metabolic Syndrome
Erica Sarchielli Paolo Comeglio Sandra Filippi Ilaria Cellai Giulia Guarnieri Alessandra Marzoppi Sarah Cipriani Linda Vignozzi Annamaria Morelli Mario Maggi 《International journal of molecular sciences》2021,22(4)
Metabolic syndrome (MetS) is known to be associated to inflammation and alteration in the hypothalamus, a brain region implicated in the control of several physiological functions, including energy homeostasis and reproduction. Previous studies demonstrated the beneficial effects of testosterone treatment (TTh) in counteracting some MetS symptoms in both animal models and clinical studies. This study investigated the effect of TTh (30 mg/kg/week for 12 weeks) on the hypothalamus in a high-fat diet (HFD)-induced animal model of MetS, utilizing quantitative RT-PCR and immunohistochemical analyses. The animal model recapitulates the human MetS features, including low testosterone/gonadotropin plasma levels. TTh significantly improved MetS-induced hypertension, visceral adipose tissue accumulation, and glucose homeostasis derangements. Within hypothalamus, TTh significantly counteracted HFD-induced inflammation, as detected in terms of expression of inflammatory markers and microglial activation. Moreover, TTh remarkably reverted the HFD-associated alterations in the expression of important regulators of energy status and reproduction, such as the melanocortin and the GnRH-controlling network. Our results suggest that TTh may exert neuroprotective effects on the HFD-related hypothalamic alterations, with positive outcomes on the circuits implicated in the control of energy metabolism and reproductive tasks, thus supporting a possible role of TTh in the clinical management of MetS. 相似文献
34.
Ignacio Hernandez Laura Tesoro Rafael Ramirez-Carracedo Javier Diez-Mata Sandra Sanchez Marta Saura Jose Luis Zamorano Carlos Zaragoza Laura Botana 《International journal of molecular sciences》2021,22(6)
In response to cardiac ischemia/reperfusion, proteolysis mediated by extracellular matrix metalloproteinase inducer (EMMPRIN) and its secreted ligand cyclophilin-A (CyPA) significantly contributes to cardiac injury and necrosis. Here, we aimed to investigate if, in addition to the effect on the funny current (I(f)), Ivabradine may also play a role against cardiac necrosis by reducing EMMPRIN/CyPA-mediated cardiac inflammation. In a porcine model of cardiac ischemia/reperfusion (IR), we found that administration of 0.3 mg/kg Ivabradine significantly improved cardiac function and reduced cardiac necrosis by day 7 after IR, detecting a significant increase in cardiac CyPA in the necrotic compared to the risk areas, which was inversely correlated with the levels of circulating CyPA detected in plasma samples from the same subjects. In testing whether Ivabradine may regulate the levels of CyPA, no changes in tissue CyPA were found in healthy pigs treated with 0.3 mg/kg Ivabradine, but interestingly, when analyzing the complex EMMPRIN/CyPA, rather high glycosylated EMMPRIN, which is required for EMMPRIN-mediated matrix metalloproteinase (MMP) activation and increased CyPA bonding to low-glycosylated forms of EMMPRIN were detected by day 7 after IR in pigs treated with Ivabradine. To study the mechanism by which Ivabradine may prevent secretion of CyPA, we first found that Ivabradine was time-dependent in inhibiting co-localization of CyPA with the granule exocytosis marker vesicle-associated membrane protein 1 (VAMP1). However, Ivabradine had no effect on mRNA expression nor in the proteasome and lysosome degradation of CyPA. In conclusion, our results point toward CyPA, its ligand EMMPRIN, and the complex CyPA/EMMPRIN as important targets of Ivabradine in cardiac protection against IR. 相似文献
35.
Kvin Nay William J. Smiles Jacqueline Kaiser Luke M. McAloon Kim Loh Sandra Galic Jonathan S. Oakhill Andrew L. Gundlach John W. Scott 《International journal of molecular sciences》2021,22(8)
As life expectancy has increased, particularly in developed countries, due to medical advances and increased prosperity, age-related neurological diseases and mental health disorders have become more prevalent health issues, reducing the well-being and quality of life of sufferers and their families. In recent decades, due to reduced work-related levels of physical activity, and key research insights, prescribing adequate exercise has become an innovative strategy to prevent or delay the onset of these pathologies and has been demonstrated to have therapeutic benefits when used as a sole or combination treatment. Recent evidence suggests that the beneficial effects of exercise on the brain are related to several underlying mechanisms related to muscle–brain, liver–brain and gut–brain crosstalk. Therefore, this review aims to summarize the most relevant current knowledge of the impact of exercise on mood disorders and neurodegenerative diseases, and to highlight the established and potential underlying mechanisms involved in exercise–brain communication and their benefits for physiology and brain function. 相似文献
36.
Maria Buuales Maria Cristina Ballesteros-Briones Manuela Gonzalez-Aparicio Sandra Hervas-Stubbs Eva Martisova Uxua Mancheo Ana Ricobaraza Sara Lumbreras Cristian Smerdou Ruben Hernandez-Alcoceba 《International journal of molecular sciences》2021,22(8)
Immune checkpoint inhibitors (ICIs) have demonstrated remarkable efficacy in a growing number of malignancies. However, overcoming primary or secondary resistances is difficult due to pharmacokinetics issues and side effects associated with high systemic exposure. Local or regional expression of monoclonal antibodies (mAbs) using gene therapy vectors can alleviate this problem. In this work, we describe a high-capacity adenoviral vector (HCA-EFZP-aPDL1) equipped with a mifepristone-inducible system for the controlled expression of an anti-programmed death ligand 1 (PD-L1) blocking antibody. The vector was tested in an immune-competent mouse model of colorectal cancer based on implantation of MC38 cells. A single local administration of HCA-EFZP-aPDL1 in subcutaneous lesions led to a significant reduction in tumor growth with minimal release of the antibody in the circulation. When the vector was tested in a more stringent setting (rapidly progressing peritoneal carcinomatosis), the antitumor effect was marginal even in combination with other immune-stimulatory agents such as polyinosinic-polycytidylic acid (pI:C), blocking mAbs for T cell immunoglobulin, mucin-domain containing-3 (TIM-3) or agonistic mAbs for 4-1BB (CD137). In contrast, macrophage depletion by clodronate liposomes enhanced the efficacy of HCA-EFZP-aPDL1. These results highlight the importance of addressing macrophage-associated immunoregulatory mechanisms to overcome resistance to ICIs in the context of colorectal cancer. 相似文献
37.
38.
Hydrogenation of double bonds was observed to occur during the isobutane chemical ionization mass spectrometry (MS) of unsaturated
fatty esters. Chemical ionization (CI) spectra of a series of methyl esters in the C16–C20 carbon range containing 0–4 double
bonds showed a variety of ionization characteristics in the molecular ion cluster, including hydride abstraction, charge exchange,
protonation and, for the unsaturated fatty acids (FA), hydrogenation of the double bond followed by protonation.
The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of
Agriculture over other firms or similar products not mentioned. 相似文献
39.
Acyl CoA:cholesterol acyltransferase (EC2.3.1.26, ACAT), responsible for intracellular esterification of cholesterol, may
play an important role in cholesterol trafficking within the cell, and thus, in maintenance of cellular cholesterol homeostasis.
Bile acids are potential regulators of cholesterol trafficking in the liver. Therefore, the effect of bile salts on hepatic
ACAT activity was studied in the perfused rat liver. ACAT activity was increased after liver perfusion with either taurocholate
or taurochenodeoxycholate. However, addition of these bile salts at physiological concentrationsin vitro had little effect on microsomal ACAT activity. The increase in hepatic ACAT activity due to perfusion with bile salts was
accompanied by reduced accumulation of very low density lipoprotein cholesterol in the perfusate, but there was no effect
on 3-hydroxy-3-methylglutaryl-CoA reductase activity. Hepatic ACAT activity was decreased after bile diversion for four hours
in the intact animal. This treatment had no statistically significant effect on 3-hydroxy-3-methylglutaryl-CoA reductase activity.
These data suggest that bile salts induce changes in hepatic compartmentation and traffic of cholesterol within the hepatocyte
accompanied by response of ACAT activity to maintain cellular cholesterol homeostasis. 相似文献
40.
Collagenous material was obtained from chicken feet skins and tendons, defatted with ethylic ether and treated with 0.05 M and 0.6 M NaCl solutions. Part of the material was dried at 35 degrees C in a forced air convection oven and another was freeze-dried. The air dried material had 77.2 g/100 g of collagen and the freeze-dried material 76.7 g/100 g. Both dehydrated materials showed the same behaviour for gel formation and cold water holding capacity. The material air dried had higher emulsifying capacity than the freeze-dried one. The collagen of freeze-dried material had higher solubility in 0.5 M acetic acid and water at 70 degrees C than air dried material. Gel strength, emulsion stability and water holding capacity at 60 degrees C were higher for freeze-dried material. The results indicate the potential use of these materials as functional ingredients in meat products. 相似文献