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271.
Glycerokinase activity was measured in brain and liver tissue of decreased low birth weight newborns. No glycerokinase activity was found in the brain. In the liver a relatively high activity of glycerokinase was ascertained even in very immature newborns. 相似文献
272.
273.
Jan Spacek Irena Netikova Helena Skalova Pavel Dundr Bohuslav Konopasek 《Immunological investigations》2013,42(7):643-653
ABSTRACTBackground: The objective of this study was to investigate serum levels of immunosuppressive cytokines TGF beta 1 and VEGF and count of immune cells in peripheral blood in stage II and III colorectal cancer patients.Methods: Blood samples were collected from 22 colorectal patients and 25 healthy controls before the start of treatment. All patients were examined by a clinical immunologist to exclude patients with immune disorders and autoimmune diseases. TGF beta 1 and VEGF were measured by ELISA, and anti-tumor cellular immunity cells (CD4, CD8, B cells, NK cells) were measured by flow cytometry.Results: TGF beta 1 and VEGF plasma levels were significantly increased in stage II and III colorectal patients compared with control group (both p < 0.0001). A decrease in the cellular immunity was shown in the absolute numbers of cytotoxic T lymphocytes (CD8+ ; p = 0.0240), helper T lymphocytes (CD4+ ; p = 0.0019), and natural killer cells (CD16 + CD56+; p < 0.0001) in both stage II and stage III patients. On the contrary, B lymphocyte (CD19+) serum levels were increased in colon cancer patients (p < 0.0001) compared to the control group.Conclusions: Our results show peripheral blood levels of TGF beta and VEGF were significantly increased in colorectal patients and changes in cellular anticancer immunity in comparison to control group. These results will be compared with results from Immunoscore. 相似文献
274.
275.
Charity care policies can help hospitals accurately determine, define, and account for the level of charity care they provide. This information will help hospitals budget appropriately and measure trends that will ultimately affect the organization's viability. State governments, the federal government, and the Internal Revenue Service are more closely scrutinizing not-for-profit hospitals' tax-exempt status. As a result, the American Institute of Certified Public Accountants (AICPA) has revised its requirement to report on charity care. To meet the AICPA's requirement, healthcare providers must develop their own definition of charity and determine criteria for providing care free or at a reduced rate. Setting policies to support the organization's definition of charity is necessary for the development of internal systems that promote the early identification of individuals seeking healthcare who will be unable to pay for services. Several policy implications may result from the facility's charity care determination process. For example, patients exhibiting extreme hardship might still be eligible to receive charity care even though their income and assets exceed the hospital's income guidelines. An organization planning to develop a charity care policy must first thoroughly assess its current charity care practices and cost accounting capabilities. Obtaining input from all the departments involved in the development of the charity care policy is necessary to make the transition as smooth as possible. 相似文献
276.
Explants of stria vascularis and spiral ligament of guinea pig cochlea were kept in primary culture. On the explant, proliferating marginal cells advanced by 15 microns/day, suggesting that in vivo defects of the strial epithelium can be covered by new marginal cells. The marginal cells growing in the cell culture dish had a diameter of 12.8 +/- 0.7 microns and formed an epithelial monolayer. Adjacent cells were connected by desmosomes and tight junctions. The cells were uniformly polarized. The apical membrane had small invaginations and numerous microvillus-like extensions, and the convoluted lateral membrane interdigitated with adjacent cells. The basal infoldings were smaller in cultured cells than in vivo; mitochondria were dispersed in the entire cytoplasm rather than concentrated in basolateral infoldings. The basal membrane infoldings of cultured marginal cells did not interdigitate with underlying fibroblast-like cells. Marginal cells were separated from underlying fibroblast-like cells by a fluid-filled space which was sometimes enlarged, leading to the formation of "domes" in the otherwise planar epithelium. 相似文献
277.
Germline mutations in two major susceptibility genes BRCA1 and BRCA2 contribute to the majority of inherited breast and ovarian cancers. Besides the germline mutation, tumor progression depends on the loss of a wild-type allele. Allelic losses in the BRCA1 and BRCA2 loci have also been detected in a high proportion of sporadic breast tumors, suggesting the role of these genes in the development of non-inherited breast cancer. Forty unselected breast tumors were analyzed for the loss of heterozygosity (LOH) at BRCA1 and BRCA2 regions and tumors with allelic deletions were screened for the presence of acquired genetic alterations in respective genes. 21.1% of 38 informative tumor samples carried LOH at the BRCA1 locus whereas 33.3% of 39 informative samples showed LOH at the BRCA2 locus. Pathogenic truncating mutations in the BRCA1 gene were found in two tumor samples with allelic losses, whereas no mutations were identified in the BRCA2 gene. Mutations were not detected in non-tumor samples from the same individuals, which indicated that the BRCA1 allele was inactivated by somatic mutations in tumor tissue. The c.1116G>A (1235G>A) nonsense mutation (p.W372X) belongs to the genetic abnormalities detected infrequently in hereditary tumors; the c.3862delG (3981delG) frameshift mutation (p.E1288fsX1306) is a novel gene alteration. The occurrence of inactivating somatic mutations in sporadic breast tumors suggested the role of the BRCA1 gene in tumorigenesis in at least a minor group of patients with non-familial breast cancer. 相似文献
278.
František Kolář Enn K. Seppet Roland Vetter Jiří Procházka Jan Grünermel Kersti Zilmer Bohuslav Ošťádal 《Pflügers Archiv : European journal of physiology》1992,421(1):26-31
Newborn rats were rendered hyperthyroid (daily subcutaneous injections of L-triiodothyronine, 10 g 100 g–1 body weight) or hypothyroid (0.05% 6-n-propyl-2-thiouracil in drinking water to nursing mothers) during the first 3 weeks of postnatal life. Compared with the euthyroid group, hyperthyroidism resulted in: (1) cardiac enlargement with right ventricular preponderance, (2) increased cardiac contractile function, (3) increased Ca2+ uptake by the sarcoplasmic reticulum (SR), (4) decreased sensitivity to the negative inotropic effect of verapamil and (5) greater inhibition of contractile function by ryanodine. Hypothyroidism generally resulted in opposite changes. The data suggest that the development of the heart and its contractile function during early postnatal life depends on the plasma level of thyroid hormones. In particular, the relative contribution of the SR and sarcolemmal Ca2+ transport to the control of cardiac contractility seems to be markedly affected by altered thyroid states. The postnatal maturation of the SR function is accelerated in hyperthyroidism but retarded in hypothyroidism. Consequently, hyperthyroid hearts appear to be less dependent and hypothyroid ones more dependent on trans-sarcolemmal Ca2+ fluxes when compared with age-matched euthyroid animals. 相似文献
279.
Summary: Morphogens, a class of secreted proteins that regulate gene expression in a concentration-dependent manner, are responsible for directing nearly all lineage fate choices during embryogenesis. In the thymus, morphogen signal pathways consisting of WNT, Hedgehog, and the transforming growth factor-β superfamily are active and have been implicated in various developmental processes including proliferation, survival, and differentiation of maturing thymocytes. Intriguingly, it has been inferred that some of these morphogen signal pathways differentially affect γδ and αβ T-cell development or maintenance, but their role in T-cell lineage commitment has not been directly probed. We have recently identified a modulator of morphogen signaling that significantly influences binary γδ versus αβ T-cell lineage diversification. In this review, we summarize functions of morphogens in the thymus and provide a highly speculative model of integrated morphogen signals, potentially directing the γδ versus αβ T-cell fate determination process. 相似文献
280.
Jirina Kolinska Vera Lisa Jessica A Clark Hana Kozakova Marie Zakostelecka Ludmila Khailova Marek Sinkora Andrea Kitanovicova Bohuslav Dvorak 《Journal of interferon & cytokine research》2008,28(5):287-296
The multifunctional cytokine interleukin-18 (IL-18) is an important mediator in intestinal inflammatory processes. The aim of this study was to evaluate the constitutive expression of IL-18 and its receptors (IL-18Ralpha and IL-18Rbeta) in intestinal epithelial cells (IEC) stimulated by tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). In addition, cellular proliferation and evaluation of brush border enzymes as differentiation markers were studied. Nontransformed rat intestinal epithelial IEC-6 cells were grown on an extracellular matrix (ECM) in medium with or without TNF-alpha, IFN-gamma, or a combination of both. Gene expression of IL-18, its receptors and apoptotic markers was evaluated using real-time PCR. Expression of IL-18Ralpha protein was demonstrated by flow cytometry and Western blot. Enzymatic activities of brush border enzymes and caspase-1 were determined. The constitutive expression of IL-18, IL-18Ralpha and IL-18Rbeta mRNAs and proteins were detected in IEC-6 cells. The biologically active form of IL-18 was released in response to TNF-alpha and IFN-gamma treatment. Exogenous IL-18 had no effect on cellular proliferation, brush border enzyme activities, and gene expression of apoptotic markers. However, the addition of IL-18 stimulated production and release of the chemokine IL-8. These data suggest that IEC-6 cells may be not only a source of IL-18 but also a target for its action. 相似文献