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11.
Antigenic proteins of 36 and 29 kDa were localized in Spirometra mansoni plerocercoid (sparganum) immunohistochemically by avidin biotin complex (ABC) staining. When polyclonal antibodies such as BALB/c mouse serum immunized with crude saline extract of sparganum or confirmed sparganosis sera were reacted as primary antibodies, the positive chromogen (3-amino, 9-ethylcarbazole) reactions were recognized at syncytial tegument, tegumental cells, muscle and parenchymal cells and lining cells of excretory canals. A monoclonal antibody (MAb) which was reacting to 36 and 29 kDa proteins in the extract of the worm was localized at the syncytial tegument and tegumental cells. The present results suggested that the potent antigenic proteins of 36 and 29 kDa in sparganum were produced at the tegumental cells and transported to the syncytial tegument. 相似文献
12.
E S Kang R E Gates T M Chiang A H Kang 《Biochemical and biophysical research communications》1979,86(3):769-778
Intact adipocytes exhibit ectoprotein kinase activity as reflected by their ability to catalyze the transfer of the terminal phosphate of (γ-32P) ATP to histone added to a cell suspension. This activity is substrate, time and cell number dependent. Lineweaver-Burk plots gave Km and Vmax values for ATP of 5 × 10?5 M and 7.14 pmoles/min/1.5 × 105 cells. Cyclic AMP but not cyclic GMP in μM concentrations stimulates ectoprotein kinase activity. The controlled tryptic digestion of intact cells results in reduction of ectoprotein kinase activity. This activity is not due to leakage of intracellular protein kinases during the preparative procedure nor to penetration of histone into the cells. Additional phosphoproteins not accessible to endogenous protein kinase activity are also localized on the external surface of the intact fat cell. 相似文献
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John H. Highberger Clare Corbett Andrew H. Kang Jerome Gross 《Biochemical and biophysical research communications》1978,83(1):43-49
Because alignment of the amino acid sequences of chick skin collagen α2-CB3 (1) with the relevant portion of chick skin collagen α1-CB7 (2) suggested that a Gly-X-Y triplet may have been missed in the latter, the peptide TM-2, produced by tryptic digestion of maleylated α1-CB7, was reinvestigated. Cleavage by trypsin at the unblocked lysine at position 18, and isolation of the resulting COOH-terminal peptide, showed this to be a 15-residue peptide containing a previously unrecognized Gly-Pro-Hyp triplet. Sequencing of the peptide showed this to occupy positions 4 through 6, or 56 through 58 of α1-CB7. The latter thus has 271 instead of 268 residues, and the α1[I] chain 1055 instead of 1052. 相似文献
15.
QuangMinh Nguyen Arya Bagus Boedi Iswanto Geon Hui Son Uyen Thi Vuong Jihyun Lee JinHo Kang Walter Gassmann Sang Hee Kim 《Molecular Plant Pathology》2022,23(9):1390
During pathogenesis, effector proteins are secreted from the pathogen to the host plant to provide virulence activity for invasion of the host. However, once the host plant recognizes one of the delivered effectors, effector‐triggered immunity activates a robust immune and hypersensitive response (HR). In planta, the effector AvrRps4 is processed into the N‐terminus (AvrRps4N) and the C‐terminus (AvrRps4C). AvrRps4C is sufficient to trigger HR in turnip and activate AtRRS1/AtRPS4‐mediated immunity in Arabidopsis; on the other hand, AvrRps4N induces HR in lettuce. Furthermore, AvrRps4N‐mediated HR requires a conserved arginine at position 112 (R112), which is also important for full‐length AvrRps4 (AvrRps4F) processing. Here, we show that effector processing and effector recognition in lettuce are uncoupled for the AvrRps4 family. In addition, we compared effector recognition by lettuce of AvrRps4 and its homologues, HopK1 and XopO. Interestingly, unlike for AvrRps4 and HopK1, mutation of the conserved R111 in XopO by itself was insufficient to abolish recognition. The combination of amino acid substitutions arginine 111 to leucine with glutamate 114 to lysine abolished the XopO‐mediated HR, suggesting that AvrRps4 family members have distinct structural requirements for perception by lettuce. Together, our results provide an insight into the processing and recognition of AvrRps4 and its homologues. 相似文献
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Keun Soo Ahn Sung-Tae Hong Yu Na Kang Jung Hyeok Kwon Mi Jeong Kim Tae Jun Park Yong Hoon Kim Tae Jin Lim Koo Jeong Kang 《The Korean journal of parasitology》2012,50(4):357-360
A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''. 相似文献
19.
间断低氧对大鼠下丘脑超微结构及前增食欲素水平的影响 总被引:1,自引:0,他引:1
目的探讨睡眠中间断低氧对大鼠下丘脑前增食欲素及受体水平的影响以及下丘脑超微结构的变化。方法大鼠分成对照组、间断低氧组和持续低氧组,分别给予吸入空气,持续低氧和间断低氧气体,并在实验开始后1d、3d、1w和4w应用RT-PCR方法测定大鼠下丘脑前增食欲素及受体水平,分析其间的变化关系,电镜观察下丘脑的超微结构变化。结果与对照组和持续低氧组比较,间断低氧4w后大鼠下丘脑前增食欲素mRNA水平明显降低,受体水平升高,但在持续低氧和对照组之间无明显差异。在低氧后1d、3d、7d后大鼠下丘脑前增食欲素mRNA降低,受体水平升高,在4w后,持续低氧组则接近正常。急性持续低氧大鼠超微结构变化更严重,而慢性间断低氧变化更持久。结论慢性间断低氧可以引起下丘脑前增食欲素下降及受体水平升高,急性持续低氧也可引起上述变化,而慢性持续低氧未引起增食欲素改变;慢性间断低氧大鼠下丘脑超微结构表现为严重而持久的变化。 相似文献
20.
Kang YJ 《Experimental biology and medicine (Maywood, N.J.)》2008,233(9):1059-1065
Traditional Chinese medicine (TCM) has a long history of development and application and has demonstrated on evidence basis its efficacy in the treatment of many diseases affecting multiple organ systems. In particular, TCM is effective in the prevention and treatment of chronic diseases and metabolic syndromes. However, the value of TCM has not been fully recognized worldwide due to the lack of definitive information of active ingredients in almost any TCM preparation. Novel functional genomics and proteomics approaches provide alternate perspectives on the mechanism of action of TCM. The target molecules on which TCM either activates or inactivates can be identified by functional genomics and proteomics, thus the affected critical signaling pathway cascades leading to effective recovery of chronic diseases can be studied. Several TCM preparations have been available for the treatment of liver fibrosis and cirrhosis, even advanced liver cirrhosis that has been shown to be irreversible and has no US-FDA approved therapy. In the TCM-treated livers with fibrosis and cirrhosis, some critical molecules that are significantly involved in the recovery can be identified through functional genomics and proteomics studies. These molecules become novel targets for drug discovery and development and candidates for the development of gene therapy. Gene therapy developed based on this strategy for the treatment of advanced liver fibrosis and cirrhosis in animal models has obtained promising results. This process thus establishes a herbogenomics approach to understand mechanisms of action of TCM and to identify effective molecular targets for the discovery and development of novel therapeutics. 相似文献