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51.
52.
Currently, there is no international consensus on the best treatment regimen for patients with advanced resectable gastric carcinoma. In the United States, where a limited lymph-node dissection is frequently performed, adjuvant chemoradiotherapy after surgery is the standard treatment. In Europe, intensified perioperative chemotherapy is commonly administered. In Japan and South Korea, postoperative S-1-based adjuvant chemotherapy after surgery with D2 lymph-node dissection is the standard treatment. Several ongoing trials are currently evaluating the optimal sequence of chemotherapy, radiotherapy, and surgery, as well as the place of targeted therapeutic agents in the treatment of advanced gastric carcinoma.  相似文献   
53.
Induction of senescence by chemotherapy was initially characterized as a suppressive response that prevents tumor cell proliferation. However, in response to treatment, it is not really known how cells can survive senescence and how irreversible this pathway is. In this study, we analyzed cell escape in response to irinotecan, a first line treatment used in colorectal cancer that induced senescence. We detected subpopulations of cells that adapted to chemotherapy and resumed proliferation. Survival led to the emergence of more transformed cells that induced tumor formation in mice and grew in low adhesion conditions. A significant amount of viable polyploid cells was also generated following irinotecan failure. Markers such as lgr5, CD44, CD133 and ALDH were downregulated in persistent clones, indicating that survival was not associated with an increase in cancer initiating cells. Importantly, malignant cells which resisted senescence relied on survival pathways induced by Mcl-1 signaling and to a lesser extent by Bcl-xL. Depletion of Mcl-1 increased irinotecan efficiency, induced the death of polyploid cells, prevented cell emergence and inhibited growth in low-adhesion conditions. We therefore propose that Mcl-1 targeting should be considered in the future to reduce senescence escape and to improve the treatment of irinotecan-refractory colorectal cancers.  相似文献   
54.
The aggressive biological behavior of mantle cell lymphoma (MCL) and its short response to current treatment highlight a great need for better rational therapy. Herein, we investigate the ability of ABT-199, the Bcl-2-selective BH3 mimetic, to kill MCL cells. Among MCL cell lines tested (n = 8), only three were sensitive (LD50 < 200 nM). In contrast, all primary MCL samples tested (n = 11) were highly sensitive to ABT-199 (LD50 < 10 nM). Mcl-1 and Bcl-xL both confer resistance to ABT-199-specific killing and BCL2/(BCLXL + MCL1) mRNA ratio is a strong predictor of sensitivity. By mimicking the microenvironment through CD40 stimulation, we show that ABT-199 sensitivity is impaired through activation of NF-kB pathway and Bcl-xL up-regulation. We further demonstrate that resistance is rapidly lost when MCL cells detach from CD40L-expressing fibroblasts. It has been reported that ibrutinib induces lymphocytosis in vivo holding off malignant cells from their protective microenvironment. We show here for two patients undergoing ibrutinib therapy that mobilized MCL cells are highly sensitive to ABT-199. These results provide evidence that in situ ABT-199 resistance can be overcome when MCL cells escape from the lymph nodes. Altogether, our data support the clinical application of ABT-199 therapy both as a single agent and in sequential combination with BTK inhibitors.  相似文献   
55.
Dysregulation of cell metabolism is critical for the growth properties of cancer cells. The purpose of this study was to understand the role of substrate transport across the mitochondrial membrane to sustain the metabolic shift and redox defense in cancer cells. Mitochondrial carrier SLC25A10 is up-regulated in a variety of tumors and is involved in regulating intracellular levels of reactive oxygen species. We show that knockdown of SLC25A10 in A549 cells changed the growth properties to a less malignant phenotype and casued increased glutamine dependency and sensitivity to oxidative stress. The metabolic alteration was linked to an energy metabolic shift from glycolysis to mitochondrial oxidative phosphorylation illustrated by increased expression of glutamate dehydrogenase, decreased expression of lactate dehydrogenase due to down-regulation of hypoxia inducible factor 1α. We identified effects on NADPH production linked to the growth changes observed in SLC25A10 knockdown cells, demonstrated by decreased NADPH production in cells deprived of glutamine. The contribution of SLC25A10 to reprogram cell metabolism and to regulate cell growth suggests SLC25A10 as a novel target for anti-cancer strategies.  相似文献   
56.
57.
It was examined how juvenile psychiatric disorders and adult schizotypal symptoms are associated. 731 patients of the Department of Child and Adolescent Psychiatry of the University Medical Centre Utrecht, the Netherlands, with mean age of 12.1 years (SD = 4.0) were reassessed at the mean age of 27.9 years (SD = 5.7) for adult schizotypal symptoms using the Schizotypal Personality Questionnaire-Revised (Vollema, Schizophr Bull 26(3):565–575, 2000). Differences between 13 juvenile DSM categories and normal controls (n = 80) on adult schizotypal total and factor scores were analyzed, using (M)ANCOVA. Pervasive developmental disorders (PDD), attention deficit hyperactivity disorders (ADHD), deferred diagnosis, sexual and gender identity disorders and depressive disorders had higher SPQ total scores when compared to normal controls (p < 0.001). Higher levels of disorganized schizotypal symptoms were found for PDD, ADHD, and deferred diagnosis (p < 0.001). The same diagnostic groups showed higher level of negative schizotypal symptoms, which was likewise true for sexual and gender identity disorders, depressive disorders, disruptive disorders, and the category of ‘Other conditions that may be a focus of clinical attention’ (p < 0.001). No differences with normal controls were found for adult positive schizotypal symptoms (p < 0.110). The current findings are suggestive of the idea that psychiatric disorders in childhood or adolescence are a more general expression of a liability to schizophrenia spectrum pathology in future life. In addition, specific patterns of adult schizotypal symptomatology are associated with different types of juvenile psychiatric disorder.  相似文献   
58.
It is unclear whether symptoms of autism spectrum disorder (ASD) in young children in the population fit the three-factor structure of ASD as described in the DSM-IV, and cluster together in individual subjects. This study analysed questionnaire data on ASD symptoms filled in by mothers of 11,332 18-month-old children that was collected in the context of the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health. Confirmatory Factor Analyses showed that the three-factor model had a significantly better fit then the two- and one-factor model of ASD symptoms. Latent class analysis revealed four homogeneous groups of children (classes) with different scores for Social Interaction and Communication at one hand and Stereotypies/Rigidity at the other hand.  相似文献   
59.
Progressive multifocal leucoencephalopathy due to JC virus is a rare complication of liver transplantation. Only four cases have already been described in the literature. This disease is difficult to differentiate from leucoencephalopathy associated with immunosuppressive drugs such as cyclosporin or tacrolimus. Positive diagnosis of progressive multifocal leucoencephalopathy no longer requires cerebral biopsy. It must be confirmed by positive JC virus RNA amplification in the cerebrospinal fluid. We report a case of progressive multifocal leucoencephalopathy occurring 18 months after liver transplantation for hepatitis C-related cirrhosis.  相似文献   
60.
Vascular calcification contributes to cardiovascular morbidity and mortality. A recently developed serum calcification propensity assay is based on the half-transformation time (T50) from primary calciprotein particles (CPPs) to secondary CPPs, reflecting the serum’s endogenous capacity to prevent calcium phosphate precipitation. We sought to identify and review the results of all published studies since the development of the T50-test by Pasch et al. in 2012 (whether performed in vitro, in animals or in the clinic) of serum calcification propensity. To this end, we searched PubMed, Elsevier EMBASE, the Cochrane Library and Google Scholar databases from 2012 onwards. At the end of the selection process, 57 studies were analyzed with regard to the study design, sample size, characteristics of the study population, the intervention and the main results concerning T50. In patients with primary aldosteronism, T50 is associated with the extent of vascular calcification in the abdominal aorta. In chronic kidney disease (CKD), T50 is associated with the severity and progression of coronary artery calcification. T50 is also associated with cardiovascular events and all-cause mortality in CKD patients, patients on dialysis and kidney transplant recipients and with cardiovascular mortality in patients on dialysis, kidney transplant recipients, patients with ischemic heart failure and reduced ejection fraction, and in the general population. Switching from acetate-acidified dialysate to citrate-acidified dialysate led to a longer T50, as did a higher dialysate magnesium concentration. Oral administration of magnesium (in CKD patients), phosphate binders, etelcalcetide and spironolactone (in hemodialysis patients) was associated with a lower serum calcification propensity. Serum calcification propensity is an overall marker of calcification associated with hard outcomes but is currently used in research projects only. This assay might be a valuable tool for screening serum calcification propensity in at-risk populations (such as CKD patients and hemodialyzed patients) and, in particular, for monitoring changes over time in T50.  相似文献   
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