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1.
Victoria Lladó David J. López Maitane Ibarguren María Alonso Joan B. Soriano Pablo V. Escribá Xavier Busquets 《生物化学与生物物理学报:生物膜》2014
This review summarizes the cellular bases of the effects of NaCHOleate (2-hydroxyoleic acid; 2OHOA; Minerval) against glioma and other types of tumors. NaCHOleate, activates sphingomyelin synthase (SGMS) increasing the levels of cell membrane sphingomyelin (SM) and diacylglycerol (DAG) together with reductions of phosphatidylethanolamine (PE) and phosphatidylcholine (PC). The increases in the membrane levels of NaCHOleate itself and of DAG induce a translocation and overexpression of protein kinase C (PKC) and subsequent reductions of Cyclin D, cyclin-dependent kinases 4 and 6 (CDKs 4 and 6), hypophosphorylation of the retinoblastoma protein, inhibition of E2F1 and knockdown of dihydrofolate reductase (DHFR) impairing DNA synthesis. In addition in some cancer cells, the increases in SM are associated with Fas receptor (FasR) capping and ligand-free induction of apoptosis. In glioma cell lines, the increases in SM are associated with the inhibition of the Ras/MAPK and PI3K/Akt pathways, in association with p27Kip1 overexpression. Finally, an analysis of the Repository of Molecular Brain Neoplasia Data (REMBRANDT) database for glioma patient survival shows that the weight of SM-related metabolism gene expression in glioma patients' survival is similar to glioma-related genes. Due to its low toxicity and anti-tumoral effect in cell and animal models its status as an orphan drug for glioma treatment by the European Medicines Agency (EMA) was recently acknowledged and a phase 1/2A open label, non-randomized study was started in patients with advanced solid tumors including malignant glioma. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy. 相似文献
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L. Crispoltoni S. Porcellati A. M. Del Pino A. Orlacchio G. Coata S. Arnone E. Torlone B. Cappuccini G. C. Di Renzo A. Orlacchio 《Cell biochemistry and function》2014,32(1):87-95
Several epidemiological studies showed that gestational diabetes mellitus is the most frequent metabolic disorder of pregnancy, the pathogenesis of which has yet to be completely clarified. The aim of this study was to investigate the presence and processing of caspase 3 (Casp3) and poly(ADP‐ribose) polymerase 1 (PARP1) in cord blood lymphocytes as markers of apoptosis in relation to glycaemic control during intrauterine life. Our results showed a specific positive correlation between the levels of active Casp3 (17–19 kDa) and the inactive form of PARP1 (89 kDa) in lymphocytes isolated from newborn babies of diabetic women with unbalanced glycaemic control, with a direct correlation between the activation of casp3 and the inactivation of PARP1, that makes lymphocytes unresponsive towards lipopolysaccharide stimulation, highlighting an altered functional response. Besides more studies are required to fully correlate the activation of the apoptotic process during the intrauterine life with the foetal health later in life, our study indicates that a cord blood lymphocyte, an easily accessible source, is informative about the activation of apoptotic stimuli in circulating cells of newborn babies in relation to the glycaemic control reached by the mother during pregnancy. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
4.
Carlos Fernández-Palomeque Andres Grau Joan Perelló Pilar Sanchis Bernat Isern Rafel M. Prieto Antonia Costa-Bauzá Onofre J. Caldés Oriol Bonnin Ana Garcia-Raja Armando Bethencourt Felix Grases 《PloS one》2015,10(8)
Pathological calcification generally consists of the formation of solid deposits of hydroxyapatite (calcium phosphate) in soft tissues. Supersaturation is the thermodynamic driving force for crystallization, so it is believed that higher blood levels of calcium and phosphate increase the risk of cardiovascular calcification. However several factors can promote or inhibit the natural process of pathological calcification. This cross-sectional study evaluated the relationship between physiological levels of urinary phytate and heart valve calcification in a population of elderly out subjects. A population of 188 elderly subjects (mean age: 68 years) was studied. Valve calcification was measured by echocardiography. Phytate determination was performed from a urine sample and data on blood chemistry, end-systolic volume, concomitant diseases, cardiovascular risk factors, medication usage and food were obtained. The study population was classified in three tertiles according to level of urinary phytate: low (<0.610 μM), intermediate (0.61–1.21 μM), and high (>1.21 μM). Subjects with higher levels of urinary phytate had less mitral annulus calcification and were less likely to have diabetes and hypercholesterolemia. In the multivariate analysis, age, serum phosphorous, leukocytes total count and urinary phytate excretion appeared as independent factors predictive of presence of mitral annulus calcification. There was an inverse correlation between urinary phytate content and mitral annulus calcification in our population of elderly out subjects. These results suggest that consumption of phytate-rich foods may help to prevent cardiovascular calcification evolution. 相似文献
5.
Erin J. Starzyk Michele A. Kelley Rachel N. Caskey Alan Schwartz Joan F. Kennelly Robert C. Bailey 《PloS one》2015,10(1)
Background and Objectives
The emerging science demonstrates various health benefits associated with infant male circumcision and adult male circumcision; yet rates are declining in the United States. The American Academy of Pediatrics and the Centers for Disease Control and Prevention recommend that healthcare providers present evidence-based risk and benefit information for infant male circumcision to parent(s) and guardian(s). The purpose of this study was to assess providers’ level of infant male circumcision knowledge and to identify the associated characteristics.Methods
An online survey was administered to healthcare providers in the family medicine, obstetrics, and pediatrics medical specialties at an urban academic health center. To assess infant male circumcision knowledge, a 17 point summary score was constructed to identify level of provider knowledge within the survey.Results
Ninety-two providers completed the survey. Providers scored high for the following knowledge items: adverse event rates, protects against phimosis and urinary tract infections, and does not prevent hypospadias. Providers scored lower for items related to more recent research: protection against cervical cancer, genital ulcer disease, bacterial vaginosis, and reduction in HIV acquisition. Two models were constructed looking at (1) overall knowledge about male circumcision, and (2) knowledge about male circumcision reduction in HIV acquisition. Pediatricians demonstrated greater overall infant male circumcision knowledge, while obstetricians exhibited significantly greater knowledge for the HIV acquisition item.Conclusion
Providers’ knowledge levels regarding the risks and benefits of infant male circumcision are highly variable, indicating the need for system-based educational interventions. 相似文献6.
Joan Sloan Tracy A. Warner Paul T. Scott Trudi L. Bannam David I. Berryman Julian I. Rood 《Plasmid》1992,27(3)
A newClostridium perfringens-Escherichia coli shuttle plasmid has been constructed and its complete DNA sequence compiled. The vector, pJIR418, contains the replication regions from theC. perfringens replicon pIP404 and theE. coli vector pUC18. The multiple cloning site and lacZ gene from pUC18 are also present, which means that X-gal screening can be used to select recombinants inE. coli. Both chloramphenicol and erythromycin resistance can be selected inC. perfringens andE. coli since pJIR418 carries theC. perfringens catP and ermBP genes. Insertional inactivation of either the catP or ermBP genes can also be used to directly screen recombinants in both organisms. The versatility of pJIR418 and its applicability for the cloning of toxin genes fromC. perfringens have been demonstrated by the manipulation of a cloned gene encoding the production of phospholipase C. 相似文献
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Robert R Edwards Ajay D Wasan Clifton O Bingham III Joan Bathon Jennifer A Haythornthwaite Michael T Smith Gayle G Page 《Arthritis research & therapy》2009,11(3):R61-9
Introduction
Maladaptive physiological responses to stress appear to play a role in chronic inflammatory diseases such as rheumatoid arthritis (RA). However, relatively little stress research in RA patients has involved the study of pain, the most commonly reported and most impairing stressor in RA. In the present study, we compared psychophysical and physiological responses to standardized noxious stimulation in 19 RA patients and 21 healthy controls. 相似文献9.
10.
Allison J. Bartuski Yoshiro Kamachi Charles Schick Joan Overhauser Gary A. Silverman 《Genomics》1997,43(3):321
High-molecular-weight serine proteinase inhibitors (serpins) regulate a diverse set of intracellular and extracellular processes such as complement activation, fibrinolysis, coagulation, cellular differentiation, tumor suppression, apoptosis, and cell migration. The ov-serpins are a subset of the serpin superfamily and are characterized by their high degree of homology to chicken ovalbumin, the lack of N- and C-terminal extensions, the absence of a signal peptide, and aSerrather than anAsnresidue at the penultimate position. Recently, we mapped four members of the family [SCCA1, SCCA2, PAI2, and PI5 (maspin)] to a 300-kb region within 18q21.3. Using a panel of 18q21.3 YAC clones, PCR, and DNA blotting, we mapped two additional ov-serpins, cytoplasmic antiproteinase 2 [CAP2 (PI8)] and bone marrow-associated serpin [bomapin (PI10)], to the same region. Three of the serpins, PI8, PI10, and PAI2 mapped to the same YACs, yA27D8 and yA24E4. We estimated that the size of the 18q21.3 serpin cluster spanned ∼500 kb and contained at least six serpin genes. The order wascen–PI5, SCCA2, SCCA1, PAI2, PI10, PI8–tel.The clustering of serpins at 18q21 provides new opportunities to study coordinate gene regulation and the evolution of gene families. 相似文献