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71.
72.
The number of transgenic mouse lines expressing Cre in either type of pigment cells (melanocytes and retinal pigment epithelium, RPE) is limited, and the available lines do not always offer sufficient specificity. In this study, we addressed this issue and we report on the generation of a MART‐1::Cre BAC transgenic mouse line, in which the expression of Cre recombinase is controlled by regulatory elements of the pigment cell‐specific gene MART‐1 (mlana). When MART‐1::Cre BAC transgenic mice were bred with the ROSA26‐R reporter line, ß‐galactosidase expression was observed in RPE from E12.5 onwards, and in melanocyte precursors from E17.5, indicating that the MART‐1::Cre line provides Cre recombinase activity in pigment‐producing cells rather than in a particular lineage. In addition, breeding of this mouse line to mice carrying a conditional allele of RBP‐Jκ corroborated the reported phenotypes in both pigment cell lineages, inducing hair greying and microphthalmia. Our results thus suggest, that the MART‐1::Cre line may serve as a novel and useful tool for functional studies in melanocytes and the RPE.genesis 49:403–409, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
73.
This paper reviews some of the results and the speculations presented at the Torino CD38 Meeting in June, 2006 and focused on CD38 and CD157 seen as a family of molecules acting as surface receptors of immune cells. This partisan view was adopted in the attempt to combine the enzymatic functions with what the immunologists consider key functions in different cell models. At the moment, it is unclear whether the two functions are correlated, indifferent, or independent. Here we present conclusions inferred exclusively on human cell models, namely T and B lymphocytes, dendritic cells, and granulocytes. As an extra analytical tool, we try to follow in the history of life when the enzymatic and receptorial functions were generated, mixing ontogeny, membrane localization, and cell anchorage.  相似文献   
74.
Interleukin-15 (IL-15) is a potent proinflammatory cytokine that is now considered a key component of atherosclerosis. Proinflammatory gene polymorphisms lead to variations in the production and level of the proteins. In light of these findings, we hypothesized that variations in the gene coding for IL-15 influence the risk of coronary heart disease (CHD) by modulating the IL-15 levels. To test this hypothesis, we examined 5 single nucleotide polymorphisms (SNPs) in IL-15 gene and IL-15 levels in 102 patients with acute coronary syndrome (ACS), 102 patients with chronic ischemic stable CHD and 162 healthy control subjects. This study is the first report showing the influences of IL-15 gene variants and IL-15 levels on CHD. The five single nucleotide polymorphisms (SNPs) within the IL-15 gene, G367A, C267T, A14035T, C13687A, and A10504G were carried out by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). Serum IL-15 levels were significantly higher in both acute and chronic patients than in controls. Genetic variants of IL-15 gene and IL-15 levels were associated with CHD. In conclusion, our study supports the hypothesis that genetic variation in IL-15 gene and IL-15 levels influence the risk of CHD. Further studies are needed to confirm our hypothesis.  相似文献   
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76.
The dried rhizomes of Veratrum album were individually extracted with CHCl3, acetone, and NH4OH/benzene to test the toxic effects against the Colorado potato beetle, Leptinotarsa decemlineata, which is an important agricultural pest. Fifteen compounds in various amounts were isolated from the extracts using column and thin‐layer chromatography. The chemical structures of 14 compounds were characterized as octacosan‐1‐ol ( 1 ), β‐sitosterol ( 2 ), stearic acid ( 3 ), diosgenin ( 4 ), resveratrol ( 5 ), wittifuran X ( 6 ), oxyresveratrol ( 7 ), β‐sitosterol 3‐Oβ‐D ‐glucopyranoside ( 8 ), diosgenin 3‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyronoside ( 9 ), oxyresveratrol 3‐Oβ‐D ‐glucopyranoside ( 10 ), jervine ( 11 ), pseudojervine ( 13 ), 5,6‐dihydro‐1‐hydroxyjervine ( 14 ), and saccharose ( 15 ) using UV, IR, MS, 1H‐ and 13C‐NMR, and 2D‐NMR spectroscopic methods. However, the chemical structure of 12 , an oligosaccharide, has not fully been elucidated. Compounds 4, 6, 9 , and 10 were isolated from V. album rhizomes for the first time in the current study. The toxic effects of three extracts (acetone, CHCl3, and NH4OH/benzene) and six metabolites, 2, 2 + 4, 5, 7, 8 , and 11 , were evaluated against the Colorado potato beetle. The assay revealed that all three extracts, and compounds 7, 8 , and 11 exhibited potent toxic effects against this pest. This is the first report on the evaluation of the toxic effects of the extracts and secondary metabolites of V. album rhizomes against L. decemlineata. Based on these results, it can be concluded that the extracts can be used as natural insecticides.  相似文献   
77.
Hritcu  Lucian  Bagci  Eyup  Aydin  Emel  Mihasan  Marius 《Neurochemical research》2015,40(9):1799-1809
Neurochemical Research - Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains,...  相似文献   
78.
S Aydin  MN Eren  S Aydin  IH Ozercan  AF Dagli 《Peptides》2012,37(2):233-239
This study aimed to examine the effects of CPB on salusin-α, salusin-β and apelin-36 bioactive peptides in people who are planned to undergo coronary artery bypass graft (CABG) operation due to coronary artery disease and to explore whether these peptides are produced in human aortic, saphenous and arterial tissues. The study included age and BMI matched 15 patients who underwent CABG operation by CPB. In order to determine salusin-α, salusin-β and apelin-36 levels, venous blood samples were collected before induction of anesthesia (T1), before CPB (T2), 5min before the removal of cross-clamp (T3), 5min after the removal of cross-clamp (T4), upon arrival in the intensive care (T5), at postoperative 24th hour (T6) and 72nd hour (T7). Salusin and apelin expressions of the tissues were shown by immunohistochemical method. Peptide amounts of sera and tissues were measured using ELISA. Salusins production by vessels occurs in fibroblast cells of the media in the aorta and smooth muscle cells of the media in the LIMA and saphena. Apelin is produced by endothelial cells of the intima and fibroblast cells of the media in the aorta and by smooth muscle cells of the media in the LIMA and saphena. Changes in the levels of salusin-β and apelin-36 were significant during CPB. Salusin-α, salusin-β and apelin-36 are locally synthesized in the arteries and veins. Salusins and apelin-36 might be important markers in the CPB, and also that salusin-β was more specific in comparison to salusin-α.  相似文献   
79.
Conjugated linoleic acid (CLA) has attracted as novel type of fatty acids having unusual health-promoting properties such as anticarcinogenic and antiobesitic effects. The present work employed castor oil as substrate for one-pot production of CLA using washed cells of Lactobacillus plantarum (L. plantarum) and lipases as catalysts. Among the screened lipases, the lipase Rhizopus oryzae (ROL) greatly assisted resting cells to produce CLA. Mass spectral analysis of the product showed that two major isomers of CLA were produced in the reaction mixture i.e. cis-9, trans-11 56.55% and trans-10, cis-12 43.45%. Optimum factors for CLA synthesis were found as substrate concentration (8 mg/mL), pH (6.5), washed cell concentration (12% w/v), and incubation time of 20 h. Hence, the combination of ROL with L. plantarum offers one pot production of CLA selectively using castor oil as a cost-effective substrate.  相似文献   
80.
Evolutionary conservation of protein interaction properties has been shown to be a valuable indication for functional importance. Here we use homology interface modeling of 10 Ras-effector complexes by selecting ortholog proteins from 12 organisms representing the major eukaryotic branches, except plants. We find that with increasing divergence time the sequence similarity decreases with respect to the human protein, but the affinities and association rate constants are conserved as predicted by the protein design algorithm, FoldX. In parallel we have done computer simulations on a minimal network based on Ras-effector interactions, and our results indicate that in the absence of negative feedback, changes in kinetics that result in similar binding constants have strong consequences on network behavior. This, together with the previous results, suggests an important biological role, not only for equilibrium binding constants but also for kinetics in signaling processes involving Ras-effector interactions. Our findings are important to take into consideration in system biology approaches and simulations of biological networks.  相似文献   
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