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21.
Bulut V Ilhan F Yucel AY Onal S Ilhan Y Godekmerdan A 《Memórias do Instituto Oswaldo Cruz》2001,96(5):669-671
Hydatid disease is caused by Echinococcus granulosus. In this study, we aimed to investigate the benefit of monitoring cases with hydatid cyst by means of immune components in patients in a long-term follow-up after surgery. Eighty-four preoperative and postoperative serum samples from 14 cases undergoing surgery for hydatid disease were evaluated in terms of immune parameters, such as total and specific IgE, IgG, IgM, IgA and complement. Total and specific IgE were determined by ELISA. Specific IgG levels were measured by indirect hemagglutination.Total IgG, IgM, IgA and complement (C3 and C4) were detected by nephelometry. Imaging studies were also carried out during the follow-up. In none of the patients hydatid cysts were detected during the follow-up. Total IgE levels in the sera of the patients decreased to normal six months after surgery. Although specific IgE against echinococcal antigens decreased one year after operation, levels were still significantly high. There were no changes in the levels of anti-Echinococcus IgG and total IgG in follow-up period. Additionally, other parameters, such as IgA, IgM, C3 and C4, were not affected. 相似文献
22.
Conversion of gastric mucosa to intestinal metaplasia in Cdx2-expressing transgenic mice 总被引:23,自引:0,他引:23
Mutoh H Hakamata Y Sato K Eda A Yanaka I Honda S Osawa H Kaneko Y Sugano K 《Biochemical and biophysical research communications》2002,294(2):470-479
Gastric intestinal metaplasia occurs as a pathological condition in the gastric mucosa. To clarify how an intestine-specific homeobox gene, Cdx2, affects the morphogenesis of gastric mucosa, we generated transgenic mice expressing Cdx2 in parietal cells. Until Day 18 after birth, the number of parietal cells inthegastric mucosa of transgenic mice was the same as for their normal littermates. However, at Day 19, we detected several glands in which parietal cells disappeared and the proliferating zone moved from the isthmus to the base of the glands. Thereafter, parietal cells decreased gradually and disappeared at Day 37. All of the gastric mucosal cells, except for enterochromaffin-like (ECL) cells, were completely replaced by intestinal metaplasia, consisting of goblet cells, enteroendocrine cells, and absorptive cells expressing alkaline phosphatase. Pseudopyloric gland metaplasia was also formed. The transgenic mouse is a very useful model for clarifying physiological differentiation of gastric and intestinal cell lineages and analyzing the molecular events from intestinal metaplasia to adenocarcinoma. 相似文献
23.
Tissue malondialdehyde and adenosine triphosphatase level after experimental liver ischaemia-reperfusion damage 总被引:2,自引:0,他引:2
Functional irregularities due to damage after ischaemia-reperfusion vary depending upon the organs affected. High energy phosphates such as ATP and ADP are destroyed after ischaemia-reperfusion damage. Subsequently, protons and inorganic phosphates accumulate within the cells and the proton pumps such as adenosine triphosphatase (ATPase), which maintain intracellular ion balance are damaged. In the present study, malondialdehyde (MDA), a product of lipid peroxidation, was measured as an indicator of tissue damage. Additionally, we measured sodium-potassium-ATPase levels and determined the interactions between MDA and Na+-K+ ATPase levels. A total of 31 female guinea pigs were divided into four groups: sham operated guinea pigs (group 1), ischaemia-reperfusion (group 2), ischaemia-reperfusion + superoxide dismutase (SOD) (group 3), ischaemia-reperfusion + allopurinol (group 4). Following reperfusion, the livers of guinea pigs in each group were removed for histopathological examination and the levels of MDA and Na+-K+ ATPase were determined in homogenized tissue samples. There was a statistically significant (p < 0.05) reduction in tissue MDA levels in group 2 when compared with group 1. The level of tissue MDA in groups 3 and 4 was significantly lower than tissue MDA levels of group 2. However, there was a statistically significant (p < 0.05) reduction in tissue Na+-K+ ATPase levels of group 2 when compared with group 1. Similarly, the level of tissue Na+-K+ ATPase in groups 3 and 4 was significantly higher than the tissue Na+-K+ ATPase levels of group 2. The results of the histopathologic examination also revealed the beneficial effects of the use of SOD and allopurinol in preventing liver damage in cases of ischaemia-reperfusion. Although the levels of MDA and Na+-K+ ATP ase in group 2 were not equal to the level in group 1, antioxidant therapy significantly improved the tendency to reverse the effects of ischaemia-reperfusion and to protect the liver from damage due to ischaemia-reperfusion. 相似文献
24.
Halifeoglu I Canatan H Ustundag B Ilhan N Inanc F 《Cell biochemistry and function》2000,18(4):263-267
Paint thinner is a commonly used industrial solvent with considerable potential for abuse by inhalation. Paint thinner is taken into the body by inhalation or by contact with the skin. Paint thinner is oxidized gradually by cytochrome P450-dependent monooxygenase and consequently free radicals are produced. In the present study we measured plasma malondialdehyde (MDA, a product of lipid peroxidation) levels as an indicator of oxidative damage and activity levels of antioxidant enzymes gluthatione peroxidase (GSH-Px) and superoxide dismutase (SOD) in erythrocytes of a group of people (n = 18) working with paint thinner. The control group was composed of 18 healthy adults. There was a statistically significant (p < 0.001) increase in MDA (2.0+/-0.7 nmol ml(-1)) and GSH-Px (86.5+/-16.6 U g(-1) Hb) activity levels in people working with paint thinner compared with control subjects (MDA: 1.0+/-0.3 nmol ml(-1); GSH-Px: 53.9+/-14.5 U g(-1) Hb). Similarly, there was also an increase (p < 0.05) in the SOD levels (1079+/-214.6 U g(-1) Hb) of people working with paint thinner compared with controls (953.3+/-46.7 U g(-1) Hb). Based on our results, it can be concluded that paint thinner inhalation may increase lipid peroxidation and consequently induce antioxidant enzymes. 相似文献
25.
S. Rasoul V. van Ommen J. Vainer M. Ilhan L. Veenstra R. Erdem L.A.W. Ruiters R. Theunissen J.C.A. Hoorntje 《Netherlands heart journal》2015,23(4):224-231
Background
There are controversial data regarding infarct-related artery only (IRA-PCI) revascularisation versus multivessel revascularisation (MV-PCI) in ST-elevation myocardial infarction (STEMI) patients with multivessel disease undergoing primary percutaneous coronary intervention (PCI). We performed a meta-analysis comparing outcome in same stage MV-PCI versus IRA-PCI in STEMI patients with multivessel disease.Methods
Systematic searches of studies comparing MV-PCI with IRA-PCI in the MEDLINE and the Cochrane Database of systematic reviews were conducted. A meta-analysis was performed of all available studies. Primary outcome was all-cause mortality. Secondary endpoints were re-infarction, revascularisation, bleeding and major adverse cardiac events (MACE).Results
A total of 15 studies were identified with a total number of 35,975 patients. Mortality rate was significantly higher in the MV-PCI group compared with the IRA-PCI group, odds ratio (OR): 1.64 (1.46–1.85). Both the incidence of re-infarction and re-PCI were significantly lower in the MV-PCI group compared with the IRA-PCI group: OR 0.54 (0.34–0.88) and OR 0.67 (0.48–0.93), respectively. Bleeding complications occurred more often in the MV-PCI group as compared with the IRA-PCI group: OR 1.24 (1.08–1.42). Rates of MACE were comparable between the two groups.Conclusions
MV-PCI during the index of primary PCI in STEMI patients is associated with a higher mortality rate, a higher risk of bleeding complications, but lower risk of re-intervention and re-infarction and comparable rates of MACE. 相似文献26.
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29.
Pedrini B Placzek WJ Koculi E Alimenti C LaTerza A Luporini P Wüthrich K 《Journal of molecular biology》2007,372(2):277-286
Ciliates of Euplotes species constitutively secrete pleiotropic protein pheromones, which are capable to function as prototypic autocrine growth factors as well as paracrine inducers of mating processes. This paper reports the amino acid sequence and the NMR structure of the pheromone En-6 isolated from the antarctic species Euplotes nobilii. The 63-residue En-6 polypeptide chain forms three alpha-helices in positions 18-25, 36-40 and 46-56, which are arranged in an up-down-up three-helix bundle forming the edges of a distorted trigonal pyramid. The base of the pyramid is covered by the N-terminal heptadecapeptide segment, which includes a 3(10)-turn of residues 3-6. This topology is covalently anchored by four long-range disulfide bonds. Comparison with the smaller pheromones of E. raikovi, a closely related species living in temperate waters, shows that the two-pheromone families have the same three-helix bundle architecture. It then appears that cold-adaptation of the En proteins is primarily related to increased lengths of the chain-terminal peptide segments and the surface-exposed loops connecting the regular secondary structures, and to the presence of solvent-exposed clusters of negatively charged side-chains. 相似文献
30.
Yaylim-Eraltan I Arzu Ergen H Arikan S Okay E Oztürk O Bayrak S Isbir T 《Cell biochemistry and function》2007,25(6):731-737
The effects of 1,25-dihydroxyvitamin D3 are mediated by binding to a specific intracellular vitamin D receptor (VDR), which has been identified in a variety of tissues. Certain polymorphisms in the VDR gene have been associated with various neoplasms. For this purpose, we studied whether VDR TaqI or FokI genotype are associated with serum 25-hydroxyvitamin D3 in 52 controls and 26 patients with colorectal cancer. Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP), and agarose gel electrophoresis tecniques were used to detect these polymorphisms. We measured 25-hydroxyvitamin D3 serum levels by ELISA. The frequencies of the FF, Ff and ff genotypes were 73.1%, 11.5%, 15.4% in colorectal cancer patients and 38.5%, 59.6%, 1.9% in healthy controls, respectively. We observed the T allele in 50% and 58.7%, and the t allele in 50% and 41.3% of colorectal cancer patients and the control group, respectively. In patients with colorectal cancer who have TT genotype, serum 25-hydroxyvitamin D3 level was lower than those with Tt/tt genotype (p:0.016). The frequency of subjects with TTFf or TtFf genotype in colorectal cancer patients was very low compared with all other genotypes (OR = 0.112; 95%CI 0.030-0.419). These data suggest that VDR TtFf or TTFf genotypes may protect against colorectal carcinogenesis. However, further studies are necessary to confirm these findings. 相似文献