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31.
Personalised cancer treatment depends on identification of therapeutically relevant biological subgroups of patients for assessing effect of treatment and to discover new therapeutic options. By analyses in heterogeneous patient populations, the effects may be lost in noise. Squamous cell carcinoma of the lung is a major killer worldwide. Despite recent advances, mortality is high and response to therapies varies greatly from patient to patient. Target search in biologically relevant subgroups may identify treatment options not so far discovered. A total of 198 patients undergoing surgery for squamous cell carcinomas of the lung were included in the study. The tumours were analysed for copy number alterations (n = 152) and gene expression from tumour (n = 188) and normal lung (n = 21), with both data levels present in 140 patients. We studied alterations in tumours harbouring mutations in TP53 and in previously published gene expression subtypes. Genes with consistent alterations in both genomic levels were identified as putative biomarkers. Results were validated in TCGA. The most convincing biomarker in TP53 mutated squamous cell carcinomas of the lung was BIRC5 with amplification in 36% of mutated samples, 5% in wild-type samples and a 17%-fold change of expression between TP53 mutated tumours and normal lung tissue. BIRC5 was significantly altered in the classical and primitive subtypes. We suggest BIRC5 as a putative predictive biomarker and putative druggable target in squamous cell lung carcinomas harbouring TP53 mutation or classified as classical and primitive subtypes.  相似文献   
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Annals of Nuclear Medicine - The Response Evaluation Criteria In Solid Tumors (RECIST) is the most used radiological method for evaluating response after peptide receptor radionuclide therapy...  相似文献   
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The purpose of this study was to determine if elevated myocardial glycogen content could obviate Ca(2+) overload and subsequent myocardial injury in the setting of low oxygen and diminished exogenous substrate supplies. Isolated harp seal cardiomyocytes, recognized as having large glycogen stores, were incubated under conditions simulating ischemia (oxygen and substrate deprivation) for 1 h. Rat cardiomyocytes were used for comparison. Freshly isolated seal cardiomyocytes contained approximately 10 times more glycogen than those from rats (479 +/- 39 vs. 48 +/- 5 nmol glucose/mg dry weight (dry wt), mean +/- S.E., n = 6), and during ischemia lactate production was significantly greater in seal compared to rat cardiomyocytes (660 +/- 99 vs. 97 +/- 14 nmol/mg dry wt), while glycogen content decreased both in seal (from 479 +/- 39 to 315 +/- 58 nmol glucose/mg dry wt) and rat cardiomyocytes (from 48 +/- 5 to 18 +/- 5 nmol glucose/mg dry wt). Cellular ATP was well maintained in ischemic seal cardiomyocytes, whereas it showed a 65% decline (from 31 +/- 3 to 11 +/- 1 nmol ATP/mg dry wt) in rat cardiomyocytes. Similarly, total seal cardiomyocyte Ca(2+) content was not affected by ischemia, while Ca(2+) increased from 8.5 +/- 2.0 to 13.3 +/- 2.0 nmol/mg dry wt in ischemic rat myocytes. Rat cardiomyocytes also showed a notable decline in the percentage of rod-shaped cells in response to ischemia (from 66 +/- 4% to 30 +/- 3%), and cell morphology was unaffected in seal incubations. Addition of iodoacetate (IAA, an inhibitor of glycolysis) to seal cardiomyocytes, on top of substrate and oxygen deprivation, reduced the cellular content of ATP by 52.9 +/- 4.4% (from 25 +/- 4 to 11 +/- 2 nmol ATP/mg dry wt) and the percentage of rod-shaped myocytes from 51 +/- 3% to 28 +/- 4%, while total Ca(2+) content was unchanged by these conditions. Seal cardiomyocytes thus tolerate low oxygen conditions better than rat cardiomyocytes. This finding is most likely due to a higher glycolysis rate in seals, fueled by larger myocardial glycogen stores.  相似文献   
36.
The metabolic syndrome, which is a set of lipid and nonlipid risk factors of metabolic origin linked with insulin resistance, is believed to be associated with an elevated risk for cardiovascular disease, but few have studied this association in prospective long-term cardiovascular outcomes trials. Placebo data from the Scandinavian Simvastatin Survival Study (4S) and the Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS/TexCAPS) were used post hoc to estimate the long-term relative risk of major coronary events (MCEs) associated with the metabolic syndrome, after excluding diabetes mellitus. In 4S and AFCAPS/TexCAPS, respectively, placebo-treated patients with the metabolic syndrome were 1.5 (95% confidence interval 1.2 to 1.8) and 1.4 (95% confidence interval 1.04 to 1.9) times more likely to have MCEs than those without it. Of the components of the metabolic syndrome, low high-density lipoprotein levels were associated with elevated risk of MCEs in both studies, whereas high triglycerides in 4S and elevated blood pressure and obesity in AFCAPS/TexCAPS were associated with significantly increased relative risk. Patients with the metabolic syndrome showed increased risk of MCEs irrespective of their Framingham-calculated 10-year risk score category (>20% vs 相似文献   
37.
Lipopolysaccharide (LPS) and related bacterial products can be recognized by host inflammatory cells in a particulate, bacterium-bound form, as well as in various soluble, released forms. In the present study we have compared the mechanisms used by LPS, detoxified LPS (DLPS), and mannuronic acid polymers (M-polymers), in solution or covalently linked to particles, in stimulating monocytes to tumor necrosis factor (TNF) production. The addition of recombinant LPS binding protein (LBP) and/or soluble CD14 (sCD14) enhanced the production of TNF from monocytes stimulated with soluble LPS, DLPS, or M-polymer, but did not affect the response to M-polymer or DLPS attached to particles. Treatment of monocytes with antibody to CD14, CD18, or CD11b showed that CD14, but not CR3 (CD11b/CD18), mediated monocyte TNF production in response to the soluble antigens. In contrast, anti-CD14, anti-CD11b and anti-CD18 monoclonal antibodies all inhibited the response to the particulate stimuli. On the other hand, B975, a synthetic analog of Rhodobacter capsulatus lipid A, completely abrogated the monocyte TNF response induced by LPS but did not affect the TNF induction by DLPS or M-polymer, either in soluble or particulate forms. These data demonstrate that the engagement of immune receptors by bacterial products such as LPS, DLPS, and M-polymer is dependent upon the presentation form of their constituent carbohydrates, and that factors such as aggregation state, acylation, carbohydrate chain length, and solid versus liquid phase of bacterial ligands influence the mechanisms used by cells in mediating proinflammatory responses.  相似文献   
38.
The spontaneously hypertensive rat (SHR) has been proposed as an animal model for Attention-Deficit Hyperactivity Disorder (ADHD). The behavioural problems of ADHD have been suggested to be secondary to altered reinforcement mechanisms resulting from dysfunction of the mesolimbic and mesocortical dopaminergic systems. The present study therefore investigated whether there are regional differences in dopamine (DA) and acetylcholine (ACh) release and DA D2-receptor function in SHR compared to their normotensive Wistar-Kyoto (WKY) controls. The DA D2-receptor agonist, quinpirole, caused significantly greater inhibition of DA release from caudate-putamen but not from nucleus accumbens or prefrontal cortex slices of SHR relative to WKY. DA D2-receptor blockade by the antagonist, sulpiride, caused a significantly greater increase in DA release from nucleus accumbens slices of SHR compared to WKY suggesting increased efficacy of DA autoreceptors at low endogenous agonist concentrations in the nucleus accumbens of SHR. The electrically-stimulated release of DA was significantly lower in caudate-putamen and prefrontal cortex slices of SHR than in slices of WKY. This could be attributed to increased autoreceptor-mediated inhibition of DA release in caudate-putamen slices but not in the prefrontal cortex. No difference was observed between SHR and WKY with respect to DA D2-receptor-mediated inhibition of ACh release from caudate-putamen or nucleus accumbens slices, suggesting that postsynaptic DA D2-receptor function is not altered in SHR relative to WKY.  相似文献   
39.
We examined the cerebrospinal fluid (CF) taken on admission from 60 patients with infections caused by Neisseria meningitidis for presence of TNF-alpha, IL-1, and IL-6. TNF-alpha was detected in CF in 55 and 19% (p = 0.03), IL-1 in 50 and 15% (p = 0.05), and IL-6 in 98 and 100% of patients with meningitis and septic shock/bacteremia, respectively. The median IL-6 concentration in CF in patients with meningitis was 154 ng/ml, and in patients with septic shock/bacteremia it was 42 ng/ml (p = 0.001). The level of LPS in CF correlated with the level of TNF-alpha (r = 0.91, p less than 0.001), but not with the level of IL-1 and IL-6. CF levels of TNF-alpha, IL-1, and IL-6 correlated with each other (r = 0.34-0.54, p less than 0.01), with the protein concentration (r = 0.34-0.62, p less than 0.01) and inversely with the CF/blood glucose ratio (r = -0.34 to -0.67, p less than 0.01). Only the Il-6 level correlated with the leukocyte count (r = 0.37, p less than 0.01). In rabbits TNF-alpha, IL-1, and IL-6 activities sequentially appeared in CF within 3 h of injection of meningococcal LPS or viable meningococci, whereas the main infiltration of granulocytes started after 4 h. TNF-alpha was detected in serum at concentrations less than 1/100 of those in CF after administration of LPS into the subarachnoid space, and conversely, TNF-alpha was detected in CF at concentrations 1/100 of those in serum after intravenous injection of LPS. The results demonstrate that TNF-alpha, IL-1, and IL-6 are sequentially produced in the initial phase of the local inflammatory response caused by meningococci, and that the subarachnoid space and systemic circulation are separate compartments with respect to production of TNF-alpha, IL-1, and IL-6.  相似文献   
40.

Background  

The epigenetics of ovarian carcinogenesis remains poorly described. We have in the present study investigated the promoter methylation status of 13 genes in primary ovarian carcinomas (n = 52) and their in vitro models (n = 4; ES-2, OV-90, OVCAR-3, and SKOV-3) by methylation-specific polymerase chain reaction (MSP). Direct bisulphite sequencing analysis was used to confirm the methylation status of individual genes. The MSP results were compared with clinico- pathological features.  相似文献   
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