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161.
Rady PL Surendran S Vu AT Hawkins JC Michals-Matalon K Tyring SK Merren J Kumar AK Matalon R 《Genetic testing》2002,6(3):211-215
Sanfilippo A syndrome is an autosomal recessive lysosomal storage disease. This disease was reported in the Cayman Islands population with carrier frequency of 1/7 to 1/10 in the West Bay district of Grand Cayman. The carrier testing of Sanfilippo A disease for families at risk was carried out using the thermal characteristics of sulfamidase activity. In the present study, a search for mutations in the sulfamidase gene in an index family was performed. In addition, 77 individuals, relatives of children with Sanfilippo A syndrome, were also studied by single-strand conformation polymorphism (SSCP), restriction fragment-length polymorphism (RFLP) analyses, and sequencing. A single mutation, G746A (R245H), was found in the family, with the patient being homozygous and both parents and 1 of the 3 siblings being carriers. Among the 77 family members of the patient with Sanfilippo syndrome, the same mutation was found among carriers of the disease. The finding of a single mutation supports the idea of a founder effect, which facilitates accurate carrier identification of Sanfilippo A syndrome in the population of Cayman Islands. 相似文献
162.
Ahn K Yeyeodu S Collette J Madden V Arthur J Li L Erickson AH 《Traffic (Copenhagen, Denmark)》2002,3(2):147-159
In transformed mouse fibroblasts, a significant proportion of the lysosomal cysteine protease cathepsin L remains in cells as an inactive precursor which associates with membranes by a mannose phosphate-independent interaction. When microsomes prepared from these cells were resolved on sucrose gradients, this procathepsin L was localized in dense vesicles distinct from those enriched for growth hormone, which is secreted constitutively when expressed in fibroblasts. Ultrastructural studies using antibodies directed against the propeptide to avoid detection of the mature enzyme in lysosomes revealed that the proenzyme was concentrated in dense cores within small vesicles and multivesicular endosomes which labeled with antibodies specific for CD63. Consistent with the resemblance of these cores to those of regulated secretory granules, secretion of procathepsin L from fibroblasts was modestly stimulated by phorbol, 12-myristate, 13-acetate. When protein synthesis was blocked with cycloheximide and lysosomal proteolysis inhibited with leupeptin, procathepsin L was found to gradually convert to the active single-chain protease. The data suggest that when synthesis levels are high, a portion of the procathepsin L is packaged in dense cores within multivesicular endosomes localized near the plasma membrane. Gradual activation of this proenzyme achieves targeting of the proenzyme to lysosomes by a mannose phosphate receptor-independent pathway. 相似文献
163.
Hydrazinocurcumin,a novel synthetic curcumin derivative,is a potent inhibitor of endothelial cell proliferation 总被引:2,自引:0,他引:2
Shim JS Kim DH Jung HJ Kim JH Lim D Lee SK Kim KW Ahn JW Yoo JS Rho JR Shin J Kwon HJ 《Bioorganic & medicinal chemistry》2002,10(8):2439-2444
Curcumin and some of its derivatives were known as in vivo inhibitors of angiogenesis. In present study, a novel curcumin derivative, named hydrazinocurcumin (HC) was synthesized and examined for its biological activities. HC potently inhibited the proliferation of bovine aortic endothelial cells (BAECs) at a nanomolar concentration (IC(50)=520 nM) without cytotoxicity. In vivo and in vitro angiogenesis experiments showed HC as a new candidate for anti-angiogenic agent. 相似文献
164.
Bahn JH Kim AY Jang SH Lee BR Ahn JY Joo HM Kan TC Won MH Kwon HY Kang JH Kwon OS Kim HB Cho SW Lee KS Park J Choi SY 《Molecules and cells》2002,13(1):21-27
Five monoclonal antibodies that recognize porcine brain myo-inositol monophosphate phosphatase (IMPase) have been selected and designated as mAb IMPP 9, IMPP 10, IMPP 11, IMPP 15, and IMPP 17. These antibodies recognize different epitopes of the enzyme and one of these inhibited the enzyme activity. When the total proteins of the porcine brain homogenate separated by SDS-PAGE were probed with monoclonal antibodies, a single reactive protein band of 29 kDa, co-migrating with the purified porcine brain IMPase, was detected. Using the anti-IMPase antibodies as probes, the cross reactivities of the brain IMPase from human and other mammalian tissues, as well as from avian sources, were investigated. Among the human and animal tissues tested, the immunoreactive bands on Western blots appeared to have the same molecular mass of 29 kDa. In addition, there was IMPase immunoreactivity in the various neuronal populations in the rat brain. These results indicate that mammalian brains contain only one major type of immunologically similar IMPase, although some properties of the enzymes that were previously reported differ from each another. The first demonstration of the IMPase localization in the brain may also provide useful data for future investigations on the function of this enzyme in relation to various neurological diseases. 相似文献
165.
166.
Park SJ Kim JS Son WS Ahn HC Lee BJ 《Journal of biochemistry and molecular biology》2003,36(5):505-507
One of the small proteins from Helicobacter pylori, acyl carrier protein (ACP), was investigated by NMR. ACP is related to various cellular processes, especially with the biosynthesis of fatty acid. The basic NMR resonance assignment is a prerequisite for the validation of a heterologous protein interaction with ACP in H. pylori. Here, the results of the backbone (1)H, (15)N, and (13)C resonance assignments of the H. pylori ACP are reported using double- and triple-resonance techniques. About 97% of all of the (1)HN, (15)N, (13)CO, (13)Calpha, and (13)Cbeta resonances that cover 76 of the 78 non-proline residues are clarified through sequential- and specific- assignments. In addition, four helical regions were clearly identified on the basis of the resonance assignments. 相似文献
167.
Jun?Cheul?Ahn Sung?Ho?Kim Min?Young?Kim Ok?Tae?Kim Kwang?Soo?Kim Baik?HwangEmail author 《Journal of Plant Biology》2003,46(1):38-40
We studied fluctuations in the production of Hwangchil lacquer and major essential oils byDendropanax morbifera Lev. Considerable seasonal as well as intraspecific (individual-tree) variations were observed. Yields of Hwangchil lacquer as well as ß-elemene, α-selinene, ß-selinene, germacrene D, and δ-cadinene also depended on harvesting time, with levels being generally higher in July and August. 相似文献
168.
Hot-water extract from mycelia of Cordyceps sinensis as a substitute for antibiotic growth promoters 总被引:2,自引:0,他引:2
Broiler chicks were orally dosed with a hot-water extract of mycelia from Cordyceps sinensis (CS-HW) to assess possible substitution of Avilamycin as an antibiotic growth promoter (AGP). The growth performance (body weight gain and survivability) and the health index (the microflora in the small intestines and the antibody titer to Newcastle disease virus) of chicks were significantly improved in the CS-HW (600 mg/kg diet) and the Avilamycin (20 mg/kg diet) fed group in comparison with the control group (p<0.05). The Avilamycin-fed group and the CS-HW-fed group had similar growth performances but the latter gave a better microbial flora in the small intestines. These results indicate that CS-HW enhances the physiological activity in chicks and can be used as a substitute for AGPs. 相似文献
169.
An acoustic cell settler (ACS) using ultrasound at cells of 3 MHz was used to recycle Saccharomyces cerevisiae in a fermenter. The locations of both the inlet and outlet in the acoustic cell settler, which have a relatively long distance between the transducer and reflector, were optimized. A tilted settler was designed to make up for the defect in the horizontal ACS, which has a low recovery ratio. The tilted ACS gave a recovery ratio of yeast cells of about 5 during the most period of operation, which was twice that of the horizontal ACS. 相似文献
170.
Haydon CE Eyers PA Aveline-Wolf LD Resing KA Maller JL Ahn NG 《Molecular & cellular proteomics : MCP》2003,2(10):1055-1067
Mass spectrometric analysis of proteolytically derived phosphopeptides has developed into a widespread technique for the identification of phosphorylated amino acids. Using liquid chromatography-electrospray ionization tandem mass spectrometry, 14 phosphorylation sites were identified on Xenopus laevis His6-Aurora A, a highly conserved regulator of centrosome maturation and cell division. These included seven novel phosphorylation sites, Ser-12, Thr-21, Thr-103, Ser-116, Thr-122, Tyr-155, and Thr-294, as well as the previously identified regulatory sites, Ser-53, Thr-295, and Ser-349. The identification of these novel phosphorylation sites will be important for future studies aimed at elucidating the mechanisms of Aurora A regulation by phosphorylation. Furthermore, we demonstrate that a "kinase-inactive" mutant of Aurora A, K169R, still retains 10% of activity of the wild-type enzyme in vitro along with occupancy of Thr-295 and Ser-12. However, mutation of Asp-281 to Ala completely abolishes activity of the enzyme and should therefore be used preferentially as a genuine kinase-dead construct. Because of the abundance of phosphorylated residues on His6-Aurora A, we found this protein to be an ideal tool for the characterization of immobilized metal-affinity chromatography (IMAC) as a method for phosphopeptide enrichment from complex mixtures. We present a detailed analysis of the binding and elution properties of both the phosphopeptides and unphosphorylated peptides of His6-Aurora A to Fe3+-IMAC before and after methyl esterification. Moreover, we demonstrate a significant difference in enrichment of phosphopeptides when different resins are used for Fe3+-IMAC and characterize the strengths and limitations of this methodology for the study of phosphoproteomics. 相似文献