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71.
An increasing body of evidence connects alterations in the process of alternative splicing with cancer development and progression. However, a direct role of splicing factors as drivers of cancer development is mostly unknown. We analysed the gene copy number of several splicing factors in colon and lung tumours, and found that the gene encoding for the splicing factor SRSF6 is amplified and over‐expressed in these cancers. Moreover, over‐expression of SRSF6 in immortal lung epithelial cells enhanced proliferation, protected them from chemotherapy‐induced cell death and converted them to be tumourigenic in mice. In contrast, knock‐down of SRSF6 in lung and colon cancer cell lines inhibited their tumourigenic abilities. SRSF6 up‐ or down‐regulation altered the splicing of several tumour suppressors and oncogenes to generate the oncogenic isoforms and reduce the tumour‐suppressive isoforms. Our data suggest that the splicing factor SRSF6 is an oncoprotein that regulates the proliferation and survival of lung and colon cancer cells.  相似文献   
72.

Background

Social adjustment is impaired in depressed patients. The difficulty to adjust to social circumstances has been hypothesized to be one of the causes of depression, as well as a consequence of the disorder. Genetic variation in the serotonin transporter gene has been previously associated with social adjustment levels in patients with mood disorders.

Methods

We investigated whether variations on the HTR1A (rs6295) and HTR2A (rs7997012) genes were associated with levels of social adjustment using the Social Adjustment Scale in two samples of depressed patients (total n=156).

Results

Patients carrying the GG genotype of the HTR2A-rs7997012 showed better social adjustment in areas of work and family unit bonding.

Limitations

These findings did not survive correction for multiple testing and should be interpreted with caution.

Conclusion

Our finding is in line with previous observations that have associated the G allele of the HTR2A-rs7997012 with higher rate of antidepressant response. The HTR2A-rs7997012 is worthy of further investigation in studies examining factors that are related to depression course and outcome.  相似文献   
73.
Normoglycemic diabetes-prone BB/OK rats aged 33, 45 or 75 days were subjected to prophylactic insulin treatment by means of a single subcutaneous application of a sustained release insulin implant. The single application of a sustained release insulin implant decreased the incidence of diabetes or delayed the onset of the disease in BB/OK rats of all treatment groups. Prophylactic insulin administration caused a transient hypoglycemic period accompanied by an inhibition of glucose stimulated insulin secretion and a decrease of the insulin content of Langerhans' islets as detectable in vitro . Compared to islets of normoglycemic controls pancreatic islets isolated from hypoglycemic BB/OK rats within 7-21 days after the insulin application at 45 days of age displayed a decreased susceptibility of the cells to complement-dependent cytotoxicity of the monoclonal islet cell surface antibody (ICSA) K14D10 but not to the cytotoxic effect of the ICSA M3aG8. The appearance of complement-dependent antibody-mediated cytotoxicity to islet cells and pancreatic exocrine cells in serum regarded as a sign of immune dysregulation in BB/OK rats seems not to be affected by insulin prophylaxis and was detectable during hypoglycemia as well as in the subsequent normoglycemic state. In conclusion, BB/OK rats of different age can be protected from diabetes by a single application of a sustained release insulin implant. Insulin and/or hypoglycemia seem to influence the expression of cell surface antigens, thus render the islets of Langerhans less vulnerable to immune cytolysis, whereas the appearance of humoral immunological abnormalites is not affected.  相似文献   
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Abstract The balance of the 2 cytokines, osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa B ligand (soluble (s)RANKL), is known to have considerable influence on bone formation and degradation. Plasma concentrations of OPG and (s)RANKL were determined in a total of 31 long-distance runners before and immediately after running distances of either 15 or 42.195 km, respectively. In both groups of endurance runners, a significant decrease of sRANKL was observed during the run, the extent of which correlated to the running distance. Furthermore, OPG increased only in runners covering the marathon distance of 42.195 km. We hypothesize that the known positive effect of long-distance running on the skeletal mass may be mediated by the OPG/sRANKL system.  相似文献   
77.
Fate of goblet cells in experimental colitis   总被引:3,自引:0,他引:3  
We sought to correlate the characteristic changes in goblet cell morphology in the chronically inflamed large intestine of IL10 –/– mice to specific changes in goblet cell gene expression. In healthy as well as IL10 –/– mice, marked differences were found among the large intestinal regions in goblet cell morphology and gene expression. The mucin Muc2, which is a major determinant of goblet cell morphology, was expressed in most goblet cells, yet only in cells staining positive for both Alcian blue and high iron diamine. TFF3 was expressed in only a small subset of goblet cells. Inflamed colon of IL10 –/– mice still contained high numbers of small, hypotrophic goblet cells with similar histochemical staining and Muc2 and TFF3 expression patterns, contradicting the often reported goblet cell depletion in colitis. Quantitatively, the Muc2 and TFF3 levels remained relatively stabile in IL10 –/– mice. Muc2 in distal IL10 –/– colon contained significantly less sulfate residues than in controls, which may compromise its protective properties.  相似文献   
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A high percentage of cyanotic adults (37%) with cyanotic congenital cardiac disease (CCD) presented with depleted iron stores (13 of 52) or latent iron deficiency (6 of 52), even in a CCD center in which cyanotic patient phlebotomy is mostly avoided. In many of these patients, hypochromia and microcytosis was frequent, whereas hyperchromia and macrocytosis were relatively common.Furthermore, 50% of patients presented with hyperhomocysteinemia, possibly related to folate or B vitamin deficiencies, which may increase red blood cell size and color, explaining the lack of microcytosis and hypochromia in many cyanotic patients with iron deficiency.  相似文献   
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