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81.
R Alan Harris Dorottya Nagy-Szakal Sabina AV Mir Eibe Frank Reka Szigeti Jess L Kaplan Jiri Bronsky Antone Opekun George D Ferry Harland Winter Richard Kellermayer 《Epigenetics》2014,9(8):1131-1137
Inflammatory bowel diseases (IBD) are emerging globally, indicating that environmental factors may be important in their pathogenesis. Colonic mucosal epigenetic changes, such as DNA methylation, can occur in response to the environment and have been implicated in IBD pathology. However, mucosal DNA methylation has not been examined in treatment-naïve patients. We studied DNA methylation in untreated, left sided colonic biopsy specimens using the Infinium HumanMethylation450 BeadChip array. We analyzed 22 control (C) patients, 15 untreated Crohn’s disease (CD) patients, and 9 untreated ulcerative colitis (UC) patients from two cohorts. Samples obtained at the time of clinical remission from two of the treatment-naïve UC patients were also included into the analysis. UC-specific gene expression was interrogated in a subset of adjacent samples (5 C and 5 UC) using the Affymetrix GeneChip PrimeView Human Gene Expression Arrays. Only treatment-naïve UC separated from control. One-hundred-and-twenty genes with significant expression change in UC (> 2-fold, P < 0.05) were associated with differentially methylated regions (DMRs). Epigenetically associated gene expression changes (including gene expression changes in the IFITM1, ITGB2, S100A9, SLPI, SAA1, and STAT3 genes) were linked to colonic mucosal immune and defense responses. These findings underscore the relationship between epigenetic changes and inflammation in pediatric treatment-naïve UC and may have potential etiologic, diagnostic, and therapeutic relevance for IBD. 相似文献
82.
In experiments with rats a study was made of a number of factors influencing the resorption of 241Am from the gastrointestinal tract (GIT). The resorption of 241Am from GIT was found to be 120-245 times more intensive in neonatal rats, during the first 21 days after birth (a milk diet), than in adult animals. A milk diet for adult rats produced a 5-fold increase in the resorption of 241Am from GIT. The additional administration of digestive enzymes, as a homogenate from pancreas and small intestine, produced a 7--9-fold increase in the rate of 241Am resorption from GIT. 相似文献
83.
A comparative analysis of the temperature effect on the thrombin- and trypsin-catalyzed hydrolysis of synthetic substrates which are derivatives of A(alpha)-chain of fibrinogen has been carried out. The substrates have general formula: Tos-P2-Arg-OCH3 and Tos-P3-P2-Arg-OCH3, where P2-Gly, Val, MeVal; P3 = Gly, Sar. The activation parameters delta G not equal to, delta H not equal to and delta S not equal to are determined. Thrombin is shown to split the most effectively tripeptide containing amino acids sequence Gly-Gly at the subsites of P3 and P2. It is suggested to be caused by an ability of the above compound to take a bent conformation at the active site of thrombin. 相似文献
84.
E. B. Romanova O. Yu. Romanova 《Journal of Evolutionary Biochemistry and Physiology》2003,39(4):480-484
Changes of the total number of leucocytes and the leucocytic formula of peripheral blood were studied and stability of development was evaluated by the indicator of fluctuating asymmetry of populations of green frogs Rana lessonae Cam. and Rana ridibunda Pall. inhabiting city reservoirs of Nizhni Novgorod and the Nizhegorodskaya Province. The revealed changes in the amphibians white blood depending on the degree of anthropogenic effects in the studied reservoirs can be divided into two types. In the first type (the level of stability of development of populations is 2 scores according to Zakharov) there were revealed neutropenia, increased content of eosinophils, and total leucopenia. In the second type, a more intensive anthropogenic effect and deviation of the organism state from normal conditions, estimated by 3 scores (Zakharov), the leucograms of frogs were characterized by more pronounced negative alterations. Leucocytosis accompanied by neutropenia, eosinophilia, basophilia, and a decrease of the total number of lymphocytes has been established. In the absence of deviations of the stability of development from the conditionally normal state, there was revealed the balance of leucogram indicators, close to norm. An increase of the number of lymphocytes and young forms of neutrophils in the amphibian peripheral blood indicates stimulation of the processes providing the organism protective reaction. Cross-correlation between the integral indicator of stability of development, the content of eosinophils and lymphocytes has been established in individuals from populations of green frogs inhabiting the studied reservoirs. 相似文献
85.
86.
Dependence of intensity of Drosophila virilis male sexual behaviour on age-related differences was studied. Most active proved to be those age periods which correlated with the time of S-esterase elevated activity. Courtship displays were compared in strains 101 and 160, interstrain differences correlating with the S-esterase activity level. As S-esterase plays an important role in fertilization, this relationship seems to be non-random. It is quite possible that the level of S-esterase activity regulates male sexual activity in natural populations. Some variations in male courtship display in interspecies hybrids (D. virilis x D. littoralis) were demonstrated which depended on the gene dose of respective species. It may well be that in the bk and dt gene regions those genes are localized which are responsible for courtship behaviour. The analysis of sexual behaviour in interstrain and interspecies hybrids proved to be successful approach to elucidating possible role of separate chromosomes in sexual behaviour determination. 相似文献
87.
Production of exocellular higher fatty acids by Candida yeasts was studied during their growth in a mineral medium with hexadecane. The qualitative and quantitative composition of exocellular higher fatty acids was investigated during cultivation of Candida lipolytica VCM Y 2378(695) under the conditions of different aeration (5 and 80% saturation of the medium with oxygen). Palmitic (C16:0), palmitooleic (C16:1), oleic (C18:1) and linoleic (C18:2) acids predominated among other higher fatty acids. The overall amount of fatty acids increased and the content of unsaturated fatty acids decreased when the yeast growth was limited with oxygen. 相似文献
88.
Destabilization of Raf-1 by geldanamycin leads to disruption of the Raf-1-MEK-mitogen-activated protein kinase signalling pathway. 总被引:7,自引:0,他引:7 下载免费PDF全文
89.
90.
The effect of aeration on growth and production of extra- and intracellular lipids was studied in the yeast Rhodotorula glutinis. Oxygen concentration in the medium optimal for biomass formation did not favour the maximal lipid yield. Changes in the fatty acid composition of the both lipid types as a function of aeration are discussed. 相似文献