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161.
用放射杂交板定位鸡的MC4R基因以及其在鸡和人染色体上同源区的比较分析 总被引:13,自引:0,他引:13
黑素皮质素受体(melanocortin-4 receptor,MC4R)基因的突变与猪、鼠和人等的食欲、肥胖和生长有关联性,然而对鸡的MC4R基因的功能却知之甚少。为了确定鸡的MC4R基因在染色体上的位置,使用鸡-仓鼠杂交板(ChickRH6)做了该基因的定位工作。通过扩增ChickRH6杂交板上的93个样品,然后经整合分析将mC4R基因定位在2号染色体上的标记MCW0062、BCL2和OVY附近,即2q12。这个连锁图上的5个标记基于两点分析与MC4R的LOD值都大于5。同时,以MC4R基因为标记做了鸡和人的染色体比较分析。结果显示鸡的2号染色体(GGA2)和人的18号染色体(HSA18)存在同源区,且基因BCL2和肥胖基因(obesity)位于MC4R基因附近。推测鸡的MC4R基因与人的MC4R基因可能具有相似的功能。该研究揭示了鸡和人MC4R基因的染色体分布,并用杂交放射板将鸡的MC4R基因定位在2号染色体的12区带。 相似文献
162.
EGCG inhibits activation of the insulin-like growth factor-1 receptor in human colon cancer cells 总被引:8,自引:0,他引:8
Shimizu M Deguchi A Hara Y Moriwaki H Weinstein IB 《Biochemical and biophysical research communications》2005,334(3):947-953
The IGF/IGF-1R system, which includes the IGF, IGF-1R, and IGFBPs proteins, plays an important role in the development and growth of colorectal cancer. We previously reported that in the HT29 human colon cancer cell line EGCG, the major biologically active component of green tea, inhibits activation of the RTKs EGFR, HER2, and HER3, and that this is associated with inhibition of multiple downstream signaling pathways. Since IGF-1R is also a RTK, in this study we examined the effects of EGCG on the activity of IGF/IGF-1R system in human colon cancer cells. We found that the colon cancer cell lines Caco2, HT29, SW837, and SW480 express high levels of the IGF-1R receptor, and that both SW837 and SW480 cells display constitutive activation of this receptor. Treatment of SW837 cells with 20 microg/ml of EGCG (the IC50 concentration for growth inhibition) caused within 6 h a decrease in the phosphorylated (i.e., activated) form of the IGF-1R protein. At 12 h, there was a decrease in the levels of both IGF-1 protein and mRNA and within 3-6 h there was an increase in the levels of both IGFBP-3 protein and mRNA. The increased expression of the latter protein was sustained for at least 48 h. When SW837 cells were treated with EGCG for a longer time, i.e., 96 h, a very low concentration (1.0 microg/ml) of EGCG also caused inhibition of activation of IGF-1R, a decrease in the IGF-1 protein, and an increase in the IGFBP-3 protein. EGCG also caused a decrease in the levels of mRNAs that encode MMPs-7 and -9, proteins that proteolyze IGFBP-3. In addition, treatment with EGCG caused a transient increase in the expression of TGF-beta2, an inducer of IGFBP-3 expression. These findings expand the roles of EGCG as an inhibitor of critical RTKs involved in cell proliferation, providing further evidence that EGCG and related compounds may be useful in the chemoprevention or treatment of colorectal cancer. 相似文献
163.
Frédéric Santos 《American journal of physical anthropology》2018,165(1):200-205
The mean measure of divergence is a dissimilarity measure between groups of individuals described by dichotomous variables. It is well suited to datasets with many missing values, and it is generally used to compute distance matrices and represent phenograms. Although often used in biological anthropology and archaeozoology, this method suffers from a lack of implementation in common statistical software. A package for the R statistical software, AnthropMMD, is presented here. Offering a dynamic graphical user interface, it is the first one dedicated to Smith's mean measure of divergence. The package also provides facilities for graphical representations and the crucial step of trait selection, so that the entire analysis can be performed through the graphical user interface. Its use is demonstrated using an artificial dataset, and the impact of trait selection is discussed. Finally, AnthropMMD is compared to three other free tools available for calculating the mean measure of divergence, and is proven to be consistent with them. 相似文献
164.
Two new species of the genus Rhyacophila Pictet from the Indian Himalayas, i.e. Rhyacophila himalayensis n. sp. from Badrinath (Uttarakhand) of the R. divaricata branch and Rhyacophila indica n. sp. from Gangtok (Sikkim) of the R. vulgaris branch are described and illustrated. 相似文献
165.
To further understand the functions of the orexin/hypocretin system, we examined the expression and regulation of the orexin/hypocretin receptor (OX1R and OX2R) mRNA in the brain by using quantitative in situ hybridization. Expression of OX1R and OX2R mRNA exhibited distinct distribution patterns. Within the hypothalamus, expression for the OX1R mRNA was largely restricted in the ventromedial (VMH) and dorsomedial hypothalamic nuclei, while high levels of OX2R mRNA were contained in the paraventricular nucleus, VMH, and arcuate nucleus as well as in mammilary nuclei. In the amygdala, OX1R mRNA was expressed throughout the amygdaloid complex with robust labeling in the medial nucleus, while OX2R mRNA was only present in the posterior cortical nucleus of amygdala. High levels of OX2R mRNA were also observed in the ventral tegmental area. Moreover, both OX1R and OX2R mRNA were observed in the hippocampus, some thalamic nuclei, and subthalamic nuclei. Furthermore, we analyzed the effect of fasting on levels of OX1R and OX2R mRNA in the hypothalamic and amygdaloid subregions. After 20 h of fasting, levels of OX1R mRNA were significantly increased in the VMH and the medial division of amygdala. An initial decrease (14 h) and a subsequent increase (20 h) in OX1R mRNA levels after fasting were observed in the dorsomedial hypothalamic nucleus and lateral division of amygdala. Levels of OX2R mRNA were augmented in the arcuate nucleus, but remained unchanged in the dorsomedial hypothalamic nucleus, paraventricular hypothalamic nucleus, and amygdala following fasting. The time-dependent and region-specific regulatory patterns of OX1R and OX2R suggest that they may participate in distinct neural circuits under the condition of food deprivation. 相似文献
166.
Tadashi Shiraiwa Takehiro Kaito Takashi Katayama Tomoko Ikeda Joji Ishikawa Hidemoto Kurokawa 《Chirality》1999,11(4):326-329
L ‐Cysteine was condensed with glyoxylic acid monohydrate in acetic acid at 30°C to give (4R)‐2,4‐thiazolidinedicarboxylic acid [(4R)‐TDA] as a mixture of two diastereoisomers, (2R,4R)‐ and (2S,4R)‐TDA. An attempt was made to separate (2S,4R)‐TDA from the diastereoisomeric salts of (4R)‐TDA with 1‐propylamine, 2‐methyl‐2‐propylamine, benzylamine, and (R)‐ and (S)‐1‐phenylethylamines [(R)‐ and (S)‐PEA]. The salts of (2S,4R)‐TDA were preferentially crystallized as less soluble diastereoisomeric salts. When the salt with (R)‐PEA was employed, the separation was successfully achieved to afford optically pure (2S,4R)‐TDA in a yield of 41%, based on the starting amount of the diastereoisomeric mixture of (4R)‐TDA. Chirality 11:326–329, 1999. © 1999 Wiley‐Liss, Inc. 相似文献
167.
本文对采自广西涠洲岛海域细微短足软珊瑚(Cladiellasubtilis)的化学成分进行研究,经理化常数和波谱数据分析,分别鉴定为(20R,24S)-5-烯-21羧基-麦角甾-3β-醇(1)、柳珊瑚甾醇(2)、鲨肝醇(3)及麦角甾-5-烯-3β-醇(4)。对细微短足软珊瑚(Cladiella subtilis)化学成分的研究尚属首次。 相似文献
168.
Restriction fragment length polymorphism tools is an R application which supports a complete workflow of polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP), dealing with the problems which accompany analysis when PCR‐RFLP is used in diversity studies. Large numbers of different RFLP samples obtained from multiple electrophoresis runs might lead to limitations or misidentifications due to the need for band matching in most existing software applications. Due to the common problem of variation in the density of bands (i.e. distances between bands or visual intensity) in the electropherograms, it is desirable to have options for handling samples with uncertain or faint bands. As a further step in the workflow, scientists often use DNA sequencing to identify individual genotypes, so that the use of specific software to combine these tasks might be helpful. With this background, we here present an application that supports a complete workflow, starting with the analysis of single species samples by PCR‐RFLP, to PCR‐RFLP genotype identification based on a reference data set and DNA sequencing followed by similarity analysis. RFLPtools is a freely available, platform‐independent application which provides analysis functions for DNA fragment molecular weights (e.g. by RFLP analysis), including similarity calculations without the need for band matching. As it is written for the statistical software R, other statistical analyses might also be easily applied. 相似文献
169.
A binary vector, designated PROGMO, was constructed to assess the potential of the Zygosaccharomyces rouxii R/Rs recombination system for generating marker- and backbone-free transgenic potato (Solanum tuberosum) plants with high transgene expression and low copy number insertion. The PROGMO vector utilises a constitutively expressed plant-adapted R recombinase and a codA-nptII bi-functional, positive/negative selectable marker gene. It carries only the right border (RB) of T-DNA and consequently the whole plasmid will be inserted as one long T-DNA into the plant genome. The recognition sites (Rs) are located at such positions that recombinase enzyme activity will recombine and delete both the bi-functional marker genes as well as the backbone of the binary vector, leaving only the gene of interest flanked by a copy of Rs␣and RB. Efficiency of PROGMO transformation was tested by introduction of the GUS reporter gene into potato. It was shown that after 21 days of positive selection and using 300 mgl−1 5-fluorocytosine for negative selection, 29% of regenerated shoots carried only the GUS gene flanked by a copy of Rs and RB. The PROGMO vector approach is simple and might be widely applicable for the production of marker- and backbone-free transgenic plants of many crop species. 相似文献
170.
Buspirone produces a dose-dependent but short-lived elevation in striatal dopamine (DA) metabolites in the rat. , buspirone possesses an affinity similar to sulpiride for DA receptors (3H-spiperone). A moderate affinity for α1 receptors was also observed while buspirone was inactive at α2, β, muscarinic and serotonin2 receptors. This pharmacological profile as well as previous behavioral data indicate that buspirone may be a potential “atypical” neuroleptic. 相似文献