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51.
Length–weight relationships of three endangered tidal pool fish species on Jeju Island,Korea 下载免费PDF全文
H. J. Kwun J. Park H.‐S. Kim H. Bae S. J. Jeong 《Zeitschrift fur angewandte Ichthyologie》2017,33(6):1229-1230
The length–weight relationships (LWRs) of three endangered tidal pool fishes, Spratelloides gracilis (Temminck & Schlegel, 1846), Atherion elymus Jordan & Starks, 1901, and Enneapterygius etheostomus (Jordan & Snyder, 1902), from Jeju Island, Korea, were analysed. A total of 280 specimens were sampled using hand nets (mesh size 1 mm) or by dredge (mesh size 5 mm) from July 2015 to July 2016. This study provides the first LWRs for two species, a new LWR for one species, and a new maximum length data for two species. 相似文献
52.
Muthukalianan GK Lee S Yum H Ku S Kwun M Kang HG An G Chung YY 《Molecules and cells》2003,15(1):102-107
We have screened a total of 5,500 T-DNA tagging rice lines in which beta-glucuronidase (GUS) gene sequence was randomly inserted as a transgene into the plant genome. Histochemical GUS assays were carried out to select the T-DNA tagging rice lines that show its expression in anther. Of the tagging lines screened, three lines were found to express GUS specifically in the anther that is about 0.05%. Microscopic observation of the anther-expressed lines showed specific expression patterns of GUS in the anther, either gametophytic or sporophytic specificities. Southern blot analysis revealed that the integration copy number of the transgene was 2.3 in average. The detailed expression patterns were analyzed and discussed. 相似文献
53.
Wright CM Savarimuthu Francis SM Tan ME Martins MU Winterford C Davidson MR Duhig EE Clarke BE Hayward NK Yang IA Bowman RV Fong KM 《PloS one》2012,7(4):e34943
Asbestos-related lung cancer accounts for 4-12% of lung cancers worldwide. We have previously identified ADAM28 as a putative oncogene involved in asbestos-related lung adenocarcinoma (ARLC-AC). We hypothesised that similarly gene expression profiling of asbestos-related lung squamous cell carcinomas (ARLC-SCC) may identify candidate oncogenes for ARLC-SCC. We undertook a microarray gene expression study in 56 subjects; 26 ARLC-SCC (defined as lung asbestos body (AB) counts >20AB/gram wet weight (gww) and 30 non-asbestos related lung squamous cell carcinoma (NARLC-SCC; no detectable lung asbestos bodies; 0AB/gww). Microarray and bioinformatics analysis identified six candidate genes differentially expressed between ARLC-SCC and NARLC-SCC based on statistical significance (p<0.001) and fold change (FC) of >2-fold. Two genes MS4A1 and CARD18, were technically replicated by qRT-PCR and showed consistent directional changes. As we also found MS4A1 to be overexpressed in ARLC-ACs, we selected this gene for biological validation in independent test sets (one internal, and one external dataset (2 primary tumor sets)). MS4A1 RNA expression dysregulation was validated in the external dataset but not in our internal dataset, likely due to the small sample size in the test set as immunohistochemical (IHC) staining for MS4A1 (CD20) showed that protein expression localized predominantly to stromal lymphocytes rather than tumor cells in ARLC-SCC. We conclude that differential expression of MS4A1 in this comparative gene expression study of ARLC-SCC versus NARLC-SCC is a stromal signal of uncertain significance, and an example of the rationale for tumor cell enrichment in preparation for gene expression studies where the aim is to identify markers of particular tumor phenotypes. Finally, our study failed to identify any strong gene candidates whose expression serves as a marker of asbestos etiology. Future research is required to determine the role of stromal lymphocyte MS4A1 dysregulation in pulmonary SCCs caused by asbestos. 相似文献
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55.
Kyu Hyuk Kwun Geun-Joong Kim Hyun-Jae Shin 《Biotechnology and Bioprocess Engineering》2009,14(3):345-348
This study assesses the use of ultrasonication to improve the extraction process of classical solvent extraction methods for
extracting isoflavones from the kudzu roots waste. The kudzu roots waste was produced after squeezing fresh kudzu roots to
make juice. The effects of extraction time, extraction temperature, ultrasonic power, and ethanol concentration in ethanol/water
mixtures were investigated. The extraction yield was found to increase with extraction time and temperature. The application
of ultrasonication-assisted extraction (UAE) increased the extraction yield of water/ethanol mixture (20:80) at 25°C 3 fold.
A maximum amount (7.28 g) of isoflavone was obtained from 100 g of dried kudzu roots waste by UAE with water/ethanol mixture
(20:80) for 6 h at 80°C. Combining the use of ultrasonication with conventional vacuum evaporation method also reduced the
concentration time for extracts from 45 to 24 min. 相似文献
56.
Vandana Relan Leanne Morrison Kylie Parsonson Belinda E. Clarke Edwina E. Duhig Morgan N. Windsor Kevin S. Matar Rishendran Naidoo Linda Passmore Elizabeth McCaul Deborah Courtney Ian A. Yang Kwun M. Fong Rayleen V. Bowman 《PloS one》2013,8(3)
Background
Malignant mesothelioma is an aggressive tumour of serosal surfaces most commonly pleura. Characterised cell lines represent a valuable tool to study the biology of mesothelioma. The aim of this study was to develop and biologically characterise six malignant mesothelioma cell lines to evaluate their potential as models of human malignant mesothelioma.Methods
Five lines were initiated from pleural biopsies, and one from pleural effusion of patients with histologically proven malignant mesothelioma. Mesothelial origin was assessed by standard morphology, Transmission Electron Microscopy (TEM) and immunocytochemistry. Growth characteristics were assayed using population doubling times. Spectral karyotyping was performed to assess chromosomal abnormalities. Authentication of donor specific derivation was undertaken by DNA fingerprinting using a panel of SNPs.Results
Most of cell lines exhibited spindle cell shape, with some retaining stellate shapes. At passage 2 to 6 all lines stained positively for calretinin and cytokeratin 19, and demonstrated capacity for anchorage-independent growth. At passage 4 to 16, doubling times ranged from 30–72 hours, and on spectral karyotyping all lines exhibited numerical chromosomal abnormalities ranging from 41 to 113. Monosomy of chromosomes 8, 14, 22 or 17 was observed in three lines. One line displayed four different karyotypes at passage 8, but only one karyotype at passage 42, and another displayed polyploidy at passage 40 which was not present at early passages. At passages 5–17, TEM showed characteristic features of mesothelioma ultrastructure in all lines including microvilli and tight intercellular junctions.Conclusion
These six cell lines exhibit varying cell morphology, a range of doubling times, and show diverse passage-dependent structural chromosomal changes observed in malignant tumours. However they retain characteristic immunocytochemical protein expression profiles of mesothelioma during maintenance in artificial culture systems. These characteristics support their potential as in vitro model systems for studying cellular, molecular and genetic aspects of mesothelioma. 相似文献57.
A prevalent sample consists of individuals who have experienced disease incidence but not failure event at the sampling time. We discuss methods for estimating the distribution function of a random vector defined at baseline for an incident disease population when data are collected by prevalent sampling. Prevalent sampling design is often more focused and economical than incident study design for studying the survival distribution of a diseased population, but prevalent samples are biased by design. Subjects with longer survival time are more likely to be included in a prevalent cohort, and other baseline variables of interests that are correlated with survival time are also subject to sampling bias induced by the prevalent sampling scheme. Without recognition of the bias, applying empirical distribution function to estimate the population distribution of baseline variables can lead to serious bias. In this article, nonparametric and semiparametric methods are developed for distribution estimation of baseline variables using prevalent data. 相似文献
58.
DYRK1A-mediated hyperphosphorylation of Tau. A functional link between Down syndrome and Alzheimer disease 总被引:1,自引:0,他引:1
Ryoo SR Jeong HK Radnaabazar C Yoo JJ Cho HJ Lee HW Kim IS Cheon YH Ahn YS Chung SH Song WJ 《The Journal of biological chemistry》2007,282(48):34850-34857
Most individuals with Down syndrome show early onset of Alzheimer disease (AD), resulting from the extra copy of chromosome 21. Located on this chromosome is a gene that encodes the dual specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A). One of the pathological hallmarks in AD is the presence of neurofibrillary tangles (NFTs), which are insoluble deposits that consist of abnormally hyperphosphorylated Tau. Previously it was reported that Tau at the Thr-212 residue was phosphorylated by Dyrk1A in vitro. To determine the physiological significance of this phosphorylation, an analysis was made of the amount of phospho-Thr-212-Tau (pT212) in the brains of transgenic mice that overexpress the human DYRK1A protein (DYRK1A TG mice) that we recently generated. A significant increase in the amount of pT212 was found in the brains of DYRK1A transgenic mice when compared with age-matched littermate controls. We further examined whether Dyrk1A phosphorylates other Tau residues that are implicated in NFTs. We found that Dyrk1A also phosphorylates Tau at Ser-202 and Ser-404 in vitro. Phosphorylation by Dyrk1A strongly inhibited the ability of Tau to promote microtubule assembly. Following this, using mammalian cells and DYRK1A TG mouse brains, it was demonstrated that the amounts of phospho-Ser-202-Tau and phospho-Ser-404-Tau are enhanced when DYRK1A amounts are high. These results provide the first in vivo evidence for a physiological role of DYRK1A in the hyperphosphorylation of Tau and suggest that the extra copy of the DYRK1A gene contributes to the early onset of AD. 相似文献
59.
Haptoglobin (Hp) is a glycoprotein that is produced by hepatic cells and secreted into the circulation. While studying the physiologic functions of Hp, we found that Hp synthesized in THP-1 monocytic cells was largely retained within cells, although Hp is considered a secretory protein. To investigate the molecular mechanism on Hp secretion in THP-1 cells, in the present study, we examined the effect of protein kinase C (PKC) on Hp secretion. When several inhibitors of PKC isoforms were tested, only Rottlerin, a specific inhibitor of PKC-delta, completely blocked Hp secretion from cells to culture medium. To confirm the role of PKC-delta in Hp secretion, Hp-overexpressing COS7 cells were transiently transfected with a wild-type or a dominantnegative mutant of the PKC-delta gene. Mutant PKC-delta significantly inhibited Hp secretion, whereas the wild-type gene slightly increased Hp secretion. These results demonstrate that the PKC-delta signal is involved in Hp secretion. 相似文献