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31.
32.
During normal metaphase in Saccharomyces cerevisiae, chromosomes are captured at the kinetochores by microtubules emanating from the spindle pole bodies at opposite poles of the dividing cell. The balance of forces between the cohesins holding the replicated chromosomes together and the pulling force from the microtubules at the kinetochores result in the biorientation of the sister chromatids before chromosome segregation. The absence of kinetochore–microtubule interactions or loss of cohesion between the sister chromatids triggers the spindle checkpoint which arrests cells in metaphase. We report here that an MEN mutant, cdc15-2, though competent in activating the spindle assembly checkpoint when exposed to Noc, mis-segregated chromosomes during recovery from spindle checkpoint activation. cdc15-2 cells arrested in Noc, although their Pds1p levels did not accumulate as well as in wild-type cells. Genetic analysis indicated that Pds1p levels are lower in a mad2Δ cdc15-2 and bub2Δ cdc15-2 double mutants compared with the single mutants. Chromosome mis-segregation in the mutant was due to premature spindle elongation in the presence of unattached chromosomes, likely through loss of proper control on spindle midzone protein Slk19p and kinesin protein, Cin8p. Our data indicate that a slower rate of transition through the cell division cycle can result in an inadequate level of Pds1p accumulation that can compromise recovery from spindle assembly checkpoint activation. 相似文献
33.
Kyung-Jun Song Zang Geun Kim Chang Ik Zhang Yeong Hoon Kim 《Marine Mammal Science》2010,26(2):282-295
Entanglement of marine mammals in fishing gear is a global issue. It is considered a significant threat to minke whales (Balaenoptera acutorostrata) in the East Sea of Korea. A total of 214 entanglements of minke whales in this area between 2004 and 2007 were used to investigate types and parts of fishing gears involved in entanglements. The majority of entanglements were mainly caused by three types of fishing gears: set nets, pots, and gill nets (n= 207, 96.7%). Other entanglements were associated with bottom trawls, purse seines, and trawls. A total of 65 entanglements were attributed to the main and branch lines of fishing gears. The most common body part of minke whales which attached to fishing gears was the mouth (n= 63, 30.4%). Most entanglements took place within 10 nmi from land (n= 179, 86.5%), and between 10 and 220 m of water depth. The mean length of entangled minke whales in set nets was significantly smaller than that of whales in pots and gill nets samples (P < 0.001). Also, the mean body length of minke whales that entangled in the coastal area and shallow waters was significantly shorter than that of whales in the offshore area and deep waters (P < 0.001). This information can be used as fundamental data to conserve and manage this population of minke whales in the East Sea of Korea, and also to modify fishing gear to reduce entanglements. Future studies should focus on investigating the impact of these entanglements on the population and the effectiveness of mitigation measures to reduce entanglements of minke whales in this area. 相似文献
34.
35.
Subbiyan Maruthasalam Ling Yin Shiu Murugan Loganathan Wei Ching Lien Yi Lun Liu Ching Mei Sun Chih Wen Yu Shu Hsien Hung Yeong Ko Chin Ho Lin 《Plant Growth Regulation》2010,60(2):83-90
Ethylene, a gaseous plant hormone, is responsible for the initiation of reproductive development in pineapple. Reproductive
development can be forced in pineapple (Ananas comosus var. comosus) throughout the year with ethylene. Inhibition of natural flowering initiation with aviglycine [(S)-trans-2-amino-4-(2-aminoethoxy)-3-butenoic acid hydrochloride], an inhibitor of ethylene biosynthesis, provides evidence
that reproductive development in response to cold stress and short daylength is also in response to ethylene production. We
studied the effect of cold treatment of pineapple on ethylene production and flower induction by applying a short-term cold
stress to stem apices. Shoot apices of pineapple treated with ice crystals also produced twice as much ethylene as did those
of control plants and significantly more than was produced by “D” leaf basal tissue. Moreover, pineapple plants treated four
times with ice crystals or ice water were induced to flower under field conditions and the forcing efficiency, as evaluated
by the percentages of inflorescence emergence and fruit harvest, was comparable to forcing with calcium carbide (CaC2) and ethephon. In another field experiment two applications of a 1.0% solution of CaC2 or 0.15% ethephon applied at 48 h intervals was sufficient to force reproductive development of ‘Tainon 17’. Furthermore,
0.5 or 1.0% solutions of CaC2 supplemented with 0.5% activated charcoal (AC) significantly improved the forcing effectiveness of CaC2. This could/would make it possible to reduce the number or concentration, or both, of CaC2 required to effect forcing in pineapple. 相似文献
36.
Yeong C Kim Yong-Chul Jung Jun Chen Ali H Alhasan Parawee Kaewsaard Yanming Zhang Shuo Ma Steve Rosen San Ming Wang 《BMC research notes》2010,3(1):341
Background
Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the western population. Although genetic factors are considered to contribute to CLL etiology, at present genomic aberrations identified in CLL are limited compared with those identified in other types of leukemia, which raises the question of the degree of genetic influence on CLL. We performed a high-resolution genome scanning study to address this issue.Findings
Using the restriction paired-end-based Ditag Genome Scanning technique, we analyzed three primary CLL samples at a kilobase resolution, and further validated the results in eight primary CLL samples including the two used for ditag collection. From 51,632 paired-end tags commonly detected in the three CLL samples representing 5% of the HindIII restriction fragments in the genomes, we identified 230 paired-end tags that were present in all three CLL genomes but not in multiple normal human genome reference sequences. Mapping the full-length sequences of the fragments detected by these unmapped tags in seven additional CLL samples confirmed that these are the genomic aberrations caused by small insertions and deletions, and base changes spreading across coding and non-coding regions.Conclusions
Our study identified hundreds of loci with insertion, deletion, base change, and restriction site polymorphism present in both coding and non-coding regions in CLL genomes, indicating the wide presence of small genomic aberrations in chronic lymphocytic leukemia. Our study supports the use of a whole genome sequencing approach for comprehensively decoding the CLL genome for better understanding of the genetic defects in CLL.37.
Doddareddy MR Choo H Cho YS Rhim H Koh HY Lee JH Jeong SW Pae AN 《Bioorganic & medicinal chemistry》2007,15(2):1091-1105
Virtual screening of the commercial databases was done by using a three dimensional pharmacophore previously developed for T-type calcium channel blockers using CATALYSTtrade mark program. Biological evaluation of 25 selected virtual hits resulted in the discovery of a highly potent compound VH04 with IC(50) value of 0.10 microM, eight times as potent as the known selective T-type calcium channel blocker, mibefradil. Search for similar compounds yielded several hits with micro-molar IC(50) values and high T-type calcium channel selectivity. Based on the structure of the virtual hits, small molecule libraries with novel scaffolds were designed, synthesis and biological evaluation of which are currently in progress. This result shows a successful example of ligand based drug discovery of potent T-type calcium channel blockers. 相似文献
38.
Kyung Hoon Jung Jeong Hwan Kim Yeong Joong Jeon Jae Heung Lee 《Biotechnology letters》1993,15(1):65-70
Summary A novel two enzyme system of fructosyltransferase and glucose oxidase to enhance the content of the net fructo—oligosaccharide (FOS) fractions in the industrial production of FOS syrup from sucrose was devised. The net FOS content in the commercial FOS syrup has been limited only to 55–60 % due to the accumulation of glucose which acts as a feedback inhibitor of the fructosyltransferase. By supplementing glucose oxidase to the conventional FOS reaction system, we could convert the glucose to gluconic acid readily separable from neutral sugars by simple ion exchange operation in the next step. The simultaneous removal of glucose was proved effective in proceeding the reaction by fructosyltransferase further by relieving the product inhibition caused by glucose. By this way, we could raise the net FOS content as high as 90 %. 相似文献
39.
This study was designed to demonstrate the utility of capillary electrophoresis (CE) for separating high-molecular-weight poly(ethylene glycol) (PEG)-conjugated proteins. As a CE method, sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) was applied to analyze interferon alpha (IFN) modified with branched and trimer-structured PEG molecules. Five mono-PEG-IFN conjugates prepared with two branched PEGs (MW 20 and 40 kDa) and three trimer-structured PEGs (MW 23.5, 43.5, and 47 kDa) were purified by cation-exchange chromatography and their masses were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The SDS-CGE method showed high separation capacity by differentiating PEG-IFN conjugates with small differences in molecular size, such as PEG40K-, PEG43.5K-, and PEG47K-IFNs, and it was useful for checking the purity of each mono-PEG-IFN. This study shows that SDS-CGE can well be utilized in the development and quality control of PEGylated proteins prepared with various types of PEG. 相似文献
40.
Effect of weight loss on some serum cytokines in human obesity: increase in IL-10 after weight loss 总被引:2,自引:0,他引:2
Jung SH Park HS Kim KS Choi WH Ahn CW Kim BT Kim SM Lee SY Ahn SM Kim YK Kim HJ Kim DJ Lee KW 《The Journal of nutritional biochemistry》2008,19(6):371-375
Obesity is a major risk factor for hypertension, coronary artery disease and type 2 diabetes. Weight loss is associated with significant metabolic benefits. Our objective was to examine changes in adipocytokines and interleukin (IL) 10 in obese subjects before and after weight loss. We measured anthropometric parameters, adipocytokine and IL-10 in 78 obese people who had visited obesity clinics at five university hospitals (Ajou, Ulsan, Catholic, Hanyang and Yonsei) in Korea. They restricted their caloric intake to less than their usual intake (by 500 kcal), were administered sibutramine and were given a program of exercise for 12 weeks. After 12 weeks, weight, body mass index, waist circumference, hip circumference, waist-to-hip ratio, total body fat, total cholesterol, triglyceride, tumor necrosis factor alpha (TNF-alpha), IL-6, resistin and leptin had significantly decreased, while adiponectin and IL-10 had significantly increased. A bivariate correlation analysis found that increment in IL-10 and baseline IL-10 levels significantly correlated with decrement in TNF-alpha (P<.01) and baseline adiponectin (r=.52, P<.001), respectively. These results were confirmed in a multiple regression analysis. The results suggest that weight loss after caloric restriction and medical treatment in obesity can improve metabolic risk factors through changes in some cytokines. 相似文献