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831.
Background
The molecular mechanisms governing the formation of the embryonic vascular system remain poorly understood. Here, we show that Disabled-2 (Dab2), a cytosolic adaptor protein, has a pivotal role in the blood vessel formation in Xenopus early embryogenesis. 相似文献832.
S H Lee J Y Chai S T Hong W M Sohn S Huh E H Cheong S B Kang 《The Korean journal of parasitology》1989,27(3):213-216
Seven cases of Diphyllobothrium latum infection were proved by collection of worms after praziquantel treatment between October, 1986 and July, 1987. The patients were all males aged 20-44 years residing in Seoul or Ulungdo, Kyungpook Province. All of them had the history of eating several kinds of raw marine fishes, and they had never been to abroad. One of them experienced abdominal pain and 6 experienced natural discharge of a chain of worm segments, but none revealed any sign of anemia. Total 12 worms (1-3/patient) were collected after praziquantel treatment. The worms were 85-423 cm in length, and revealed the characteristic rosette-shape uterus in their gravid proglottides. The average egg size varied 61.0-65.3 x 41.7-46.1 microns. The eggs were yellowish-brown, and ovoid to elliptical. Including the present 7 cases, the total number of human D. latum infections proven by worms in Korea becomes 28 cases. 相似文献
833.
B R DasGupta D A Boroff K Cheong 《Biochemical and biophysical research communications》1968,32(6):1057-1063
834.
H S Yong C S Ooi G L Chiang W H Cheong S S Dhaliwal 《Comparative biochemistry and physiology. B, Comparative biochemistry》1985,82(2):275-278
Three temporal samples of a wild population of Mansonia uniformis were analysed for genetic variation at six gene-enzyme systems. Adenylate kinase, hexokinase (3 loci) and cathodal malate dehydrogenase were monomorphic. Phosphoglucomutase, glucose phosphate isomerase, isocitrate dehydrogenase and anodal malate dehydrogenase were polymorphic. Each of the polymorphic loci was represented by three alleles. The average heterozygosity or gene diversity was 0.0437. 相似文献
835.
Jin Sol Lee Joon Seol Bae Byung-Lae Park Hyun Sub Cheong Jeong-Hyun Kim Charisse Flerida A. Pasaje Jason Yongha Kim Tae Joon Park Soo-Taek Uh Choon-Sik Park Hyoung Doo Shin 《Genes & genomics.》2011,33(6):613-620
The human HLA class II histocompatibility antigen, DR alpha chain (HLA-DRA) is a member of the MHC class II gene family that activates T cells allowing secretion in various cytokines to immune responses. Thus, we explored whether the genetic variations in HLA-DRA gene can influence susceptibility for aspirin exacerbated respiratory disease (AERD). To carry out the investigation, 22 single nucleotide polymorphisms (SNPs) in HLA-DRA were genotyped in 592 Korean asthma patients. Logistic and regression analyseis wereas used to evaluate the P-values for associations of HLA-DRA polymorphisms with AERD and a relevant phenotype, the fall rate of forced expiratory volume in the 1st second (FEV1). Logistic analyses revealed that two variants, rs6911777 and HLA_DRA_BL1_ht3 were initially associated with AERD via dominant and recessive models (P = 0.05 and 0.01, respectively), however, the signals did not reach the threshold of significance after multiple corrections. Furthermore, we observed that fall rate of FEV1 by aspirin provocation was marginally different between AERD cases and aspirin-tolerant asthma (ATA) controls (mean = 24.63 vs 3.54, respectively). This study provides result of first association analysis between the variants of HLA-DRA and the risk of AERD, and conclusions derived from the study do not support significant roles of polymorphisms in HLA-DRA with AERD. 相似文献
836.
Inmoo Rhee Ming-Chao Zhong Boris Reizis Cheolho Cheong André Veillette 《Molecular and cellular biology》2014,34(5):888-899
Dendritic cells (DCs) capture and process antigens in peripheral tissues, migrate to lymphoid tissues, and present the antigens to T cells. PTPN12, also known as PTP-PEST, is an intracellular protein tyrosine phosphatase (PTP) involved in cell-cell and cell-substratum interactions. Herein, we examined the role of PTPN12 in DCs, using a genetically engineered mouse lacking PTPN12 in DCs. Our data indicated that PTPN12 was not necessary for DC differentiation, DC maturation, or cytokine production in response to inflammatory stimuli. However, it was needed for full induction of T cell-dependent immune responses in vivo. This function largely correlated with the need of PTPN12 for DC migration from peripheral sites to secondary lymphoid tissues. Loss of PTPN12 in DCs resulted in hyperphosphorylation of the protein tyrosine kinase Pyk2 and its substrate, the adaptor paxillin. Pharmacological inhibition of Pyk2 or downregulation of Pyk2 expression also compromised DC migration, suggesting that Pyk2 deregulation played a pivotal role in the migration defect caused by PTPN12 deficiency. Together, these findings identified PTPN12 as a key regulator in the ability of DCs to induce antigen-induced T cell responses. This is due primarily to the role of PTPN12 in DC migration from peripheral sites to secondary lymphoid organs through regulation of Pyk2. 相似文献
837.
Indeok Hwang Dilli Prasad Paudyal Seong-Ki Kim Hyeonsook Cheong 《Biotechnology and Bioprocess Engineering》2007,12(2):157-164
Inhibitors are very important in the study of hormone function. Brasinazole (Brz) is a specific inhibitor of brassinosteroids
(BRs) biosynthesis. To expand our knowledge of the molecular mechanisms of plant steroid signaling, we performed genetic screening
using medium containing Brz under dark conditions. Mutants insensitive to Brz developlonger hypocotyls than their wild type
counterparts. We isolatedabz453 as a Brz insensitive mutant. TAIL-PCR and the segregation ratio of T2 plants indicated a single T-DNA insertion at the 24-Sterol
C-methyltransferase (SMT2) gene in theabz453 mutant. Recapitulation for putative FCP serine phosphatase (FSP), the gene neighboringSMT2, indicated no significant phenotypes, but theSMT2 anti-sense (SMT2-AS) line developed longer hypocotyls than the wild type in medium containing Brz. Additionally, theSMT2-AS line displayed similar phenotypes to theabz453 line in soil including enhanced growth and smaller silique. Theabz453 andSMT2-AS mutants showed phenotypes similar to those of wild type in medium containing benzylaminopurine, pacrobutrazol and ACC (precursor
for ethylene) under dark conditions. However, when brassinolide (BL) dose response was observed, theabz453 andSMT2-AS lines showed higher sensitivity than wild type. Theabz453/det2 andabz453/bri1-119 double mutants showed enhanced growth compared to thedet2 andbri1-119 line under both dark and light conditions. Specially, in dark conditions double mutants displayed nearly 2- and 1.5-fold
longer hypocotyls thandet2 andbri1-119 plants. Brz insensitivity to theSMT2 knock-out mutant and phenotypes of double mutants indicate that not only do BRI1 and DET2 influence the BRs response, as
evidenced by hypocotyl elongation, but another sterol derived signals may also be affected in mutants, suggesting that another
pathway is involved in hypocotyl elongation due to SMT2. 相似文献
838.
Hyun-Suk Oh Sang-Ryoung Kim Won-Suk Cheong Chung-Hak Lee Jung-Kee Lee 《Applied microbiology and biotechnology》2013,97(23):10223-10231
It has been reported that an indigenous quorum quenching bacterium, Rhodococcus sp. BH4, which was isolated from a real plant of membrane bioreactor (MBR) has promising potential to control biofouling in MBR. However, little is known about quorum quenching mechanisms by the strain BH4. In this study, various characteristics of strain BH4 were investigated to elucidate its behavior in more detail in the mixed liquor of MBR. The N-acyl homoserine lactone hydrolase (AHL–lactonase) gene of strain BH4 showed a high degree of identity to qsdA in Rhodococcus erythropolis W2. The LC-ESI-MS analysis of the degradation product by strain BH4 confirmed that it inactivated AHL activity by hydrolyzing the lactone bond of AHL. It degraded a wide range of N-acyl homoserine lactones (AHLs), but there was a large difference in the degradation rate of each AHL compared to other reported AHL–lactonase-producing strains belonging to Rhodococcus genus. Its quorum quenching activity was confirmed not only in the Luria-Bertani medium, but also in the synthetic wastewater. Furthermore, the amount of strain BH4 encapsulated in the vessel as well as the material of the vessel substantially affected the quorum quenching activity of strain BH4, which provides useful information, particularly for the biofouling control in a real MBR plant from an engineering point of view. 相似文献
839.
Summary 2-Cyano-2-phenyl-1-hexanol containing chiral quaternary carbon was resolved using a lipase. Among various reaction conditions, transesterification reaction (solvent; n-hexane, lipase; Candida cylindracea) gave high selectivity(20/80). Additionally, the selectivity could be improved(13/87) when pyridine(1%) was used as an additive. The ratios of resolved alcohols were determined by GC and 1H-NMR analysis using Mosher's derivative. 相似文献