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961.
Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare type of vacuolating leukodystrophy (white matter disorder), which is mainly caused by defects in MLC1 or glial cell adhesion molecule (GlialCAM) proteins. In addition, autoantibodies to GlialCAM are involved in the pathology of multiple sclerosis. MLC1 and GLIALCAM genes encode for membrane proteins of unknown function, which has been linked to the regulation of different ion channels and transporters, such as the chloride channel VRAC (volume regulated anion channel), ClC-2 (chloride channel 2), and connexin 43 or the Na+/K+-ATPase pump. However, the mechanisms by which MLC proteins regulate these ion channels and transporters, as well as the exact function of MLC proteins remain obscure. It has been suggested that MLC proteins might regulate signalling pathways, but the mechanisms involved are, at present, unknown. With the aim of answering these questions, we have recently described the brain GlialCAM interactome. Within the identified proteins, we could validate the interaction with several G protein-coupled receptors (GPCRs), including the orphan GPRC5B and the proposed prosaposin receptors GPR37L1 and GPR37. In this review, we summarize new aspects of the pathophysiology of MLC disease and key aspects of the interaction between GPR37 receptors and MLC proteins.  相似文献   
962.
The cardiovascular benefit of statins is well established. However, only 20% of high-risk patients remain adequately adherent after 5 years of treatment. Among reasons for discontinuation, statin associated-muscle pain symptoms are the most prevalent. Aim of the present study was to evaluate the impact of high dose atorvastatin on skeletal muscle mitochondrial activity, aerobic and anaerobic exercise, and axonal excitability in a murine model of atherosclerosis. ApoE-/- mice were fed 12 weeks a high-fat high-cholesterol diet alone or containing atorvastatin (40 mg/Kg/day). Outcomes were the evaluation of muscle mitochondrial functionality, locomotion, grip test, and axonal excitability (compound action potential recording analysis of Aα motor propioceptive, Aβ mechanoceptive and C nociceptive fibres). Atorvastatin led to a reduction in muscle mitochondrial biogenesis and mitochondrial ATP production. It did not affect muscular strength but led to a time-dependent motor impairment. Atorvastatin altered the responsiveness of mechanoceptive and nociceptive fibres, respectively, the Aβ and C fibres. These findings point out to a mild sensitization on mechanical, tactile and pain sensitivity. In conclusion, although the prevalence of muscular side effects from statins may be overestimated, understanding of the underlying mechanisms can help improve the therapeutic approach and reassure adherence in patients needing-to-be-treated.  相似文献   
963.
Endometrial cancer is the most common malignancy of the female genital tract. Obesity is a strong risk factor for endometrial cancer. Adipose tissue is an active endocrine organ that synthesizes biologically active cytokine peptides, called adipokines. Adiponectin and leptin are the main cytokines of adipose tissue, which may influence the development of metabolic diseases and carcinogenesis. In this scenario, we describe the role of leptin and adiponectin in the development of endometrial cancer. A better understanding of the signalling pathway of these cytokines in endometrial cancerogenesis will provide an opportunity for effective target therapy and may be usable in fertility-sparing treatment. In the future, clinical trials focusing on adipokines, molecular biology, and genetics of the tumour will be needed.  相似文献   
964.
The accumulation of specific metabolic intermediates is known to promote cancer progression. We analyzed the role of 4-pyridone-3-carboxamide-1-β-D-ribonucleoside (4PYR), a nucleotide metabolite that accumulates in the blood of cancer patients, using the 4T1 murine in vivo breast cancer model, and cultured cancer (4T1) and endothelial cells (ECs) for in vitro studies. In vivo studies demonstrated that 4PYR facilitated lung metastasis without affecting primary tumor growth. In vitro studies demonstrated that 4PYR affected extracellular adenine nucleotide metabolism and the intracellular energy status in ECs, shifting catabolite patterns toward the accumulation of extracellular inosine, and leading to the increased permeability of lung ECs. These changes prevailed over the direct effect of 4PYR on 4T1 cells that reduced their invasive potential through 4PYR-induced modulation of the CD73-adenosine axis. We conclude that 4PYR is an oncometabolite that affects later stages of the metastatic cascade by acting specifically through the regulation of EC permeability and metabolic controls of inflammation.  相似文献   
965.
Type 2 diabetes (T2D) has been considered a relentlessly worsening disease, due to the progressive deterioration of the pancreatic beta cell functional mass. Recent evidence indicates, however, that remission of T2D may occur in variable proportions of patients after specific treatments that are associated with recovery of beta cell function. Here we review the available information on the recovery of beta cells in (a) non-diabetic individuals previously exposed to metabolic stress; (b) T2D patients following low-calorie diets, pharmacological therapies or bariatric surgery; (c) human islets isolated from non-diabetic organ donors that recover from “lipo-glucotoxic” conditions; and (d) human islets isolated from T2D organ donors and exposed to specific treatments. The improvement of insulin secretion reported by these studies and the associated molecular traits unveil the possibility to promote T2D remission by directly targeting pancreatic beta cells.  相似文献   
966.
Short texts are typically composed of small number of words, most of which are abbreviations, typos and other kinds of noise. This makes the noise to signal ratio relatively high for this specific category of text. A high proportion of noise in the data is undesirable for analysis procedures as well as machine learning applications. Text normalization techniques are used to reduce the noise and improve the quality of text for processing and analysis purposes. In this work, we propose a combination of statistical and rule-based techniques to normalize short texts. More specifically, we focus our attention on SMS messages. We base our normalization approach on a statistical machine translation system which translates from noisy data to clean data. This system is trained on a small manually annotated set. Then, we study several automatic methods to extract more general rules from the normalizations generated with the statistical machine translation system. We illustrate the proposed methodology by conducting some experiments with a SMS Haitian-Créole data collection. In order to evaluate the performance of our methodology we use several Haitian-Créole dictionaries, the well-known perplexity criteria and the achieved reduction of vocabulary.  相似文献   
967.
Boolean nets are a family of Petri net models with very simple markings which are sets of places. We investigate several classes of boolean nets distinguished by different kinds of individual connections between places and transitions, as well as different ways in which these connections are combined in order to specify the effect of executing steps of transitions. The latter aspect can be captured by connection monoids. A key advantage of using connection monoids is that by describing the step semantics of a class of Petri nets in terms of a connection monoid, one can apply results developed within a general theory of Petri net synthesis. In this paper, we provide an extensive classification of boolean nets which can be described by connection monoids. This classification is based on the realisation that the different ways of interpreting combinations of connections can be made explicit using a higher level monoid. Moreover, we demonstrate that connection monoids can capture other behavioural properties of boolean nets, such as structural conflicts between transitions.  相似文献   
968.
The present narrative review gathers the studies reported so far, addressing sex differences in the effects of cold exposure, feeding pattern and age on brown adipose tissue (BAT) thermogenesis and white adipose tissue (WAT) browning. In rodents, when exposed to decreasing temperatures, females activate thermogenesis earlier. Results obtained in humans go in the same line, although they do not provide results as solid as those obtained in rodents. Regarding the effects of overfeeding, interesting sex differences on BAT thermogenic capacity have been reported, and the greater or lower sensitivity of each sex to this dietary situation seems to be dependent on the type of feeding. In the case of energy restriction, females are more sensitive than males. In addition, sex differences have also been observed in thermogenesis changes induced by phenolic compound administration. During sexual development, an increase in BAT mass and BAT activity takes place. This phenomenon is greater in boys than in girls, probably due to its relation to muscle-mass growth. The opposite situation takes place during ageing, a lifespan period where thermogenic capacity declines, this being more acute in men than in women. Finally, the vast majority of the studies have reported a higher susceptibility to developing WAT browning amongst females. The scarcity of results highlights the need for further studies devoted to analysing this issue, in order to provide valuable information for a more personalised approach.  相似文献   
969.
Precise anticancer therapies employing cytotoxic conjugates constitute a side-effect-limited, highly attractive alternative to commonly used cancer treatment modalities, such as conventional chemotherapy, radiotherapy or surgical interventions. Receptor tyrosine kinases are a large family of N-glycoproteins intensively studied as molecular targets for cytotoxic conjugates in various cancers. At the cell surface, these receptors are embedded in a dense carbohydrate layer formed by numerous plasma membrane glycoproteins. The complexity of the cell surface architecture is further increased by galectins, secreted lectins capable of recognizing and clustering glycoconjugates, affecting their motility and activity. Cell surface N-glycosylation is intensively remodeled by cancer cells; however, the contribution of this phenomenon to the efficiency of treatment with cytotoxic conjugates is largely unknown. Here, we evaluated the significance of N-glycosylation for the internalization and toxicity of conjugates targeting two model receptor tyrosine kinases strongly implicated in cancer: HER2 and FGFR1. We employed three conjugates of distinct molecular architecture and specificity: AffibodyHER2-vcMMAE (targeting HER2), vcMMAE-KCK-FGF1.E and T-Fc-vcMMAE (recognizing different epitopes within FGFR1). We demonstrated that inhibition of N-glycosylation reduced the cellular uptake of all conjugates tested and provided evidence for a role of the galectin network in conjugate internalization. In vitro binding studies revealed that the reduced uptake of conjugates is not due to impaired HER2 and FGFR1 binding. Importantly, we demonstrated that alteration of N-glycosylation can affect the cytotoxic potential of conjugates. Our data implicate a key role for cell surface N-glycosylation in the delivery of cytotoxic conjugates into cancer cells.  相似文献   
970.
Inflammatory processes play a central role in the pathogenesis of diabetic nephropathy (DN) in the early stages of the disease. The authors demonstrate that the glycolipid mimetic (Ss)-DS-ONJ is able to abolish inflammation via the induction of autophagy flux and provokes the inhibition of inflammasome complex in ex vivo and in vitro models, using adult kidney explants from BB rats. The contribution of (Ss)-DS-ONJ to reducing inflammatory events is mediated by the inhibition of classical stress kinase pathways and the blocking of inflammasome complex activation. The (Ss)-DS-ONJ treatment is able to inhibit the epithelial-to-mesenchymal transition (EMT) progression, but only when the IL18 levels are reduced by the treatment. These findings suggest that (Ss)-DS-ONJ could be a novel, and multifactorial treatment for DN.  相似文献   
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