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31.
Vakkilainen J Jauhiainen M Ylitalo K Nuotio IO Viikari JS Ehnholm C Taskinen MR 《Journal of lipid research》2002,43(4):598-603
Small, dense LDL particles are typical for FCHL. Intravascular lipid exchange and net transfer among HDL, LDL, and triglyceride-rich lipoproteins as well as lipolysis in the VLDL-IDL-LDL cascade regulate properties of LDL. We investigated postheparin plasma activities of hepatic lipase (HL) and LPL, and plasma activities of CETP and phospholipid transfer protein (PLTP) in 191 individuals from 37 Finnish FCHL families. LDL peak particle diameter (LDL size) was measured with 2-10% gradient polyacrylamide gel electrophoresis. LDL size was significantly smaller in affected FCHL family members (n = 68) as compared with nonaffected FCHL family members (n = 78) or spouses (n = 45) (25.3 +/- 1.5 nm, 26.8 +/- 1.2 nm, and 26.6 +/- 1.2 nm, respectively, P < 0.001 for both). In affected FCHL family members, serum triglycerides were the strongest correlate for LDL size (r = -0.71, P < 0.001). In univariate correlation analysis LDL size was not associated with HL, LPL, CETP, and PLTP activities. In multivariate stepwise regression analysis, however, serum triglycerides, CETP activity, HL activity, and HDL cholesterol were significant predictors of LDL size in affected FCHL subjects (adjusted r (2) = 0.642).We conclude that serum triglyceride concentration is strongly correlated with LDL size in affected FCHL subjects. After adjustment for serum triglycerides, HL and CETP activities are associated with LDL size in FCHL. 相似文献
32.
Here, a partial skeleton of Prodeinotherium bavaricum from Unterzolling (Southern Germany) is documented. The following elements are preserved and described for the first time: cervical vertebrae 1-2 and 5-7, the first thoracic vertebra, one lumbar vertebra, trapezium, metacarpals 1-5, tibia, calcaneus, endo- and mesocuneiform, cuboid, the fourth metatarsal, and some phalanges. Comparisons with the skeletons of P. bavaricum from Franzensbad (Czech Republic) and Deinotherium giganteum from Eserovo (Bulgaria) show osteological differences that are described and discussed. 相似文献
33.
Appleman LJ van Puijenbroek AA Shu KM Nadler LM Boussiotis VA 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(6):2729-2736
CD28 provides a costimulatory signal that cooperates with the TCR/CD3 complex to induce T cell activation, cytokine production, and clonal expansion. We have recently shown that CD28 directly regulates progression of T lymphocytes through the cell cycle. Although a number of signaling pathways have been linked to the TCR/CD3 and to CD28, it is not known how these two receptors cooperate to induce cell cycle progression. Here, using cell-permeable pharmacologic inhibitors of phosphatidylinositol 3-hydroxykinase (PI3K) and mitogen-activated protein kinase kinase (MEK1/2), we show that cell cycle progression of primary T lymphocytes requires simultaneous activation of PI3K- and MEK1/2-dependent pathways. Decreased abundance of cyclin-dependent kinase inhibitor p27(kip1), which requires simultaneous TCR/CD3 and CD28 ligation, was dependent upon both MEK and PI3K activity. Ligation of TCR/CD3, but not CD28 alone, resulted in activation of MEK targets extracellular signal-related kinase 1/2, whereas ligation of CD28 alone was sufficient for activation of PI3K target protein kinase B (PKB; c-Akt). CD28 ligation alone was also sufficient to mediate inactivating phosphorylation of PKB target glycogen synthase kinase-3 (GSK-3). Moreover, direct inactivation of GSK-3 by LiCl in the presence of anti-CD3, but not in the presence of anti-CD28, resulted in down-regulation of p27(kip1), hyperphosphorylation of retinoblastoma tumor suppressor gene product, and cellular proliferation. Thus, inactivation of the PI3K-PKB target GSK-3 could substitute for CD28 but not for CD3 signals. These results show that the PI3K-PKB pathway links CD28 to cell cycle progression and suggest that p27(kip1) integrates mitogenic MEK- and PI3K-dependent signals from TCR and CD28 in primary T lymphocytes. 相似文献
34.
Pantos C Malliopoulou V Paizis I Moraitis P Mourouzis I Tzeis S Karamanoli E Cokkinos DD Carageorgiou H Varonos D Cokkinos DV 《Molecular and cellular biochemistry》2003,242(1-2):173-180
It has been recently shown that long-term thyroxine administration increases the tolerance of the heart to ischaemia. The present study investigated whether thyroxine induced cardioprotection involves alterations in the pattern of p38 mitogen activated protein kinase (p38MAPK) and c-Jun NH2-terminal kinases (JNKs) activation during ischaemia-reperfusion. L-thyroxine (T4) was administered in Wistar rats (25 g/100 g/day, subcutaneously) for 2 weeks (THYR), while normal animals served as controls (NORM). NORM and THYR isolated rat hearts were perfused in Langendorff mode and subjected to 10 or 20 min of zero-flow global ischaemia only and also to 20 min of ischaemia followed by 10, 20 or 45 min of reperfusion. Postischaemic recovery of left ventricular developed pressure at 45 min of reperfusion was expressed as % of the initial value. Activation of p38 MAPK and JNKs was assessed at the different times of the experimental setting by standard Western blotting techniques using a dual phospho p38MAPK and phospho JNKs (p46/p54) antibodies. Activation of p38 MAPK was significantly attenuated during ischaemia and reperfusion in thyroxine treated hearts compared to normal hearts. JNKs were found to be activated only during the reperfusion period. The levels of phospho JNKs were found to be lower in thyroxine treated hearts as compared to untreated hearts, though not at a statistically significant level. Postischaemic functional recovery was higher in THYR as compared to NORM, p < 0.05. In summary, in hearts pretreated with thyroxine, p38 MAPK was attenuated during ischaemia and at reperfusion and this was associated with improved postischaemic recovery of function. 相似文献
35.
We measured 14 rowers and divided them into two groups according to age and years of training. Our goal has been to establish the influence of several years of programmed training on the structure of the body, oxygen carrying capacity and oxidation capacity of muscle cells, the chemical composition of blood and characteristics of pulse and lactate curves in rowers. As to the structure of the body, the two groups did not differ if we equalised them according to body height. Differences existed in the determinants of oxygen carrying capacity and oxidation capacity of muscle cells. Older rowers had lower pulse at rest, higher step test index, lower pulse immediately after the step test and in the last minute of the test on a bicycle ergometer and higher maximal oxygen pulse. While at rest, no significant differences between the groups were observed in most of the analysed substances in the blood serum. With the increase of age and training period an increase of the concentration of creatinin and activity of creatine kinase and lessening of the activity of alkaline phosphatase was noted. Length of training period lowers the levels of cholesterol and free fatty acids and increases the level of triglycerides in blood serum. An increase of the activity of creatine kinase and lactate dehydrogenase and the formation of a specific pattern of isoenzymes was observed. The pulse and lactate curve flattened and moved to the right. 相似文献
36.
In the present study we demonstrated that NO synthase and xanthine oxidase of synaptosomes isolated from rabbit brain cortex can be activated by the gas phase of cigarette smoke to produce nitric oxide and superoxide which react together to form peroxynitrite. Expose of synaptosomes, up to 3 hours, in the gas phase of cigarette smoke, a gradual increase in both nitric oxide and superoxide release that were inhibited by N-monomethyl-L-arginine (100 M) and oxypurinol (1 mM), respectively, was observed. NO synthase and xanthine oxidase activities were increased approximately three fold after treatment of synaptosomes with the gas phase of cigarette smoke as compared with the gas phase deprived of oxidants. Synaptosomes treated with the gas phase of cigarette smoke dramatically increased 3-nitrotyrosine production (used as an index of peroxynitrite formation). Synaptosomes treated with the gas phase of cigarette smoke, promptly increased malondialdehyde production with subsequent decrease of synaptosomal plasma membrane fluidity estimated by fluorescence anisotropy of 1,4-(trimethyl-amino-phenyl)-6-phenyl-hexa-1,3,5-triene. Gas phase deprived of oxidants showed a small but not statistically significant (p > 0.05) effect on both malondialdehyde and membrane fluidity. In summary, the present results indicate that activation of NO synthase and xanthine oxidase of brain cells by oxidants contained in the gas phase of cigarette smoke lead to the formation of peroxynitrite a causative factor in neurotoxicity. 相似文献
37.
Maria F. M. Braga Vassiliki Aroniadou-Anderjaska He Li 《Neurochemical research》2000,25(12):1645-1648
Subject Index
Subject Index for Neurochemical Research, Volume 25, 2000 相似文献38.
George Pentheroudakis Georgia Raptou Vassiliki Kotoula Ralph M. Wirtz Eleni Vrettou Vasilios Karavasilis Georgia Gourgioti Chryssa Gakou Konstantinos N. Syrigos Evangelos Bournakis Grigorios Rallis Ioannis Varthalitis Eleni Galani Georgios Lazaridis George Papaxoinis Dimitrios Pectasides Gerasimos Aravantinos Thomas Makatsoris Konstantine T. Kalogeras George Fountzilas 《PloS one》2015,10(5)
Background
Although host immune response is an emerging prognostic factor for colorectal cancer, there is no consensus on the optimal methodology, surrogate markers or tissue for study.Patients and Methods
Tumour blocks were prospectively collected from 344 patients with stage II/III colorectal cancer (CRC) treated with adjuvant chemotherapy. Whole section lymphocytic infiltration was studied along with mRNA expression of CD3Z, CD8, CD4, CXCL9, CXCL13, IGHM, FOXP3, SNAI2 and ESR1 by qRT-qPCR in tissue microarray (TMA) cores from the centre of tumour, invasive margin and adjacent normal mucosa.Results
Lymphocytic infiltration, deficient MMR (10.9%), KRAS (40.7%) and BRAF (4.9%) mutations or single mRNA gene expression were not prognostic. Tumour ESR1 gene expression (Hazard Ratio [HR] for relapse 2.33, 95% CI 1.35-4.02; HR for death 1.74, 95% CI 1.02-2.97) and absence of necrosis (HR for relapse 1.71, 95% CI 1.05-2.71; HR for death 1.98, 95% CI 1.14-3.43) were adverse prognostic features. We used CD3Z and CD8 expression in order to devise the mRNA-based Immune Score (mIS) and proceeded to partitioning analysis in 267 patients, with age, stage, tumour site (Right vs Left CRC), KRAS mutation and tumour mIS as input factors. Only in patients with stage III right-sided colon cancer, a low immune response was associated with inferior disease-free survival (mIS-low, HR for relapse 2.28, 95% CI 1.05-8.02). No prognostic significance was seen for tumour mIS in any other stage or site of CRC, or for a similar mIS score derived from adjacent normal mucosa. Independent adverse prognostic significance was retained in multivariable analysis for absence of necrosis, tumour ESR1 expression in all patients and low tumour mIS in stage III right-sided CRC.Conclusions
In localised CRC, mRNA-based CD3Z/CD8 profiling of tumour immune response may have stage, site and tissue-specific prognostic significance, along with ESR1 expression.Trial Registration
ANZCTR.org.au ACTRN12610000509066 相似文献39.
Heli Elovaara Teija Huusko Mikael Maksimow Kati Elima Gennady G. Yegutkin Mikael Skurnik Ulrich Dobrindt Anja Siitonen Michael J. McPherson Marko Salmi Sirpa Jalkanen 《PloS one》2015,10(11)
Escherichia coli amine oxidase (ECAO), encoded by the tynA gene, catalyzes the oxidative deamination of aromatic amines into aldehydes through a well-established mechanism, but its exact biological role is unknown. We investigated the role of ECAO by screening environmental and human isolates for tynA and characterizing a tynA-deletion strain using microarray analysis and biochemical studies. The presence of tynA did not correlate with pathogenicity. In tynA+ Escherichia coli strains, ECAO enabled bacterial growth in phenylethylamine, and the resultant H2O2 was released into the growth medium. Some aminoglycoside antibiotics inhibited the enzymatic activity of ECAO, which could affect the growth of tynA+ bacteria. Our results suggest that tynA is a reserve gene used under stringent environmental conditions in which ECAO may, due to its production of H2O2, provide a growth advantage over other bacteria that are unable to manage high levels of this oxidant. In addition, ECAO, which resembles the human homolog hAOC3, is able to process an unknown substrate on human leukocytes. 相似文献
40.
Sara Sammallahti Marius Lahti Riikka Pyh?l? Jari Lahti Anu-Katriina Pesonen Kati Heinonen Petteri Hovi Johan G. Eriksson Sonja Strang-Karlsson Anna-Liisa J?rvenp?? Sture Andersson Eero Kajantie Katri R?ikk?nen 《PloS one》2015,10(9)