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91.
92.
A novel protein kinase, TOPK (T-LAK cell-originated protein kinase), was isolated from a lymphokine-activated killer T (T-LAK) cell subtraction cDNA fragment library. The open reading frame of the TOPK gene encodes a protein of 322 amino acids, possessing a protein kinase domain profile. The cap site analysis of the 5'-end of TOPK mRNA revealed two forms, a major full-length form and a minor spliced form at the 5'-site, both encoding the same protein. A BLAST homology search and phylogenetic analysis indicated that TOPK is related to dual specific mitogen-activated protein kinase kinase (MAPKK). The transfection of the TOPK gene to COS-7 cells up-regulated a phosphorylation of p38 MAPK but not ERK1/2 or SAPK/JNK. Gel precipitation study indicated that TOPK protein can be associated with p38 in vitro. Tissue distribution of TOPK mRNA expression was specific for the testis, T-LAK cells, activated lymphoid cells, and lymphoid tumors. On the other hand, deactivated T-LAK cells did not show TOPK mRNA expression. These data suggest that TOPK is a newly identified member of a novel MEK3/6-related MAPKK that may be enrolled in the activation of lymphoid cells and support testicular functions.  相似文献   
93.
The accumulation and degradation in the endoplasmic reticulum (ER) of a truncated ER-60 protease, from which the C-terminal 89 amino acid residues have been deleted (K 417 ochre), was examined. K 417 ochre overexpressed in COS-1 cells is not secreted into the medium, but accumulates as insoluble aggregates in non-ionic detergent without degradation in unusual clump membrane structures. K 417 ochre, stably expressed, forms soluble aggregates in non-ionic detergent and is distributed in the reticular structures of ER. Under these conditions, K 417 ochre is not secreted into the medium but is degraded with a half-life time of more than 8 h. Since K 417 ochre/C all S, in which all the Cys residues of K 417 ochre are replaced by Ser, also forms aggregates, an inter-disulfide bond appears unnecessary for aggregation. In both types of aggregates, Ig heavy chain binding protein, calnexin, glucose regulated protein 94, calreticulin, ERp72, and protein disulfide isomerase are scarcely found. Since degradation of the stably expressed K 417 ochre was not inhibited by lactacystin, leupeptin, NH(4)Cl, or cytocharasin B, but was inhibited by N-acetyl-leucyl-leucyl-norleucinal, the self-aggregated abnormal protein in the lumen of ER is assumed to be degraded by an unknown protease system other than proteasome, lysosome or autophagy.  相似文献   
94.
95.
Inbred BALB/c mice are one of the most difficult inbred strains to fertilize in vitro. In this study we examined the abilities of various media used for mouse in vitro fertilization (IVF) to support capacitation and sperm penetration through the zona pellucida (ZP) of inbred BALB/c spermatozoa. Media examined were TYH, M16, CZB, mWhitten medium, T6, modified Tyrode's solution (mTyrode's), mKSOM, MEM and TCM199. Modified human tubal fluid (mHTF) was used as a control medium. When sperm were capacitated and inseminated in the same medium, mHTF showed the best fertilization (approximately 80%) scored by male pronuclear formation (<26%) at 5h post-insemination (PI). When sperm were capacitated in various media and inseminated in mHTF, sperm capacitated in TYH solution (93%) but no other media (<45%) showed a significantly higher level of sperm nuclear decondensation (SND) than mHTF at 2 h PI (approximately 65%). When sperm were capacitated in mHTF and inseminated in various media, only mTyrode's (52%) was not significantly lower than mHTF (66%) in terms of SND at 2h PI (<49%). Sperm capacitation also was examined by chlortetracycline (CTC) staining. Sperm capacitated in TYH solution showed a significantly higher percentage of capacitation (46%) than those treated in HTF (28%) and other media (<24%). These results indicate that the best approach for IVF in the BALB/c strain is capacitation in TYH and insemination in mHTF. Poor fertilization of BALB/c may result from suboptimal conditions of sperm capacitation and insemination, and overall IVF success may differ depending on strains used.  相似文献   
96.
We tested the effect of oral administration of fermented sake lees with lactic acid bacteria (FESLAB) on a murine model of allergic rhinitis upon immunization and nasal sensitization with ovalbumin (OVA). We used Lactobacillus paracasei NPSRIk-4 (isolated from sake lees), and L. brevis NPSRIv-8 (from fermented milk) as starter strains to produce the FESLAB. Oral FESLAB administration resulted in the development of significantly fewer sneezing symptoms than those seen in sham control animals given sterile water. We also found that FESLAB suppressed the allergen-induced degranulation of RBL2H3 rat basophilic leukemia cells.  相似文献   
97.
Abnormal expression of a serine protease in human dystrophic muscle   总被引:1,自引:0,他引:1  
The activities of serine protease in muscles from normal persons and from patients with progressive muscular and neuromuscular diseases have been determined. A significant increase in the level of serine protease was found in muscle of patients with Duchenne-type muscular dystrophy and with Becker-type muscular dystrophy, but the activity was not increased in muscle of a patient with amyotrophic lateral sclerosis.  相似文献   
98.
Synthesis of theanine from glutamic acid and ethylamine in the presence of ATP was observed by the use of a homogenate of tea seedlings. The mechanism of theanine biosynthesis is discussed.  相似文献   
99.
100.
B cell-activating factor (BAFF) is a cytokine belonging to the tumor necrosis factor (TNF) superfamily. It has been reported that BAFF is elevated in patients with autoimmune pancreatitis and contributes to the malignant potential of blood cancers and solid tumors. In this study, clinical evidence of increased BAFF levels in patients with pancreatic ductal adenocarcinoma (PDAC) was obtained, and the roles and mechanisms of BAFF in PDAC were clarified in human tissues of PDAC and from in vitro data of PDAC cell lines. Serum levels of BAFF in patients with PDAC were significantly higher than in healthy subjects (p = 0.0121). Patients with UICC stage IV PDAC (T1-4, N0-1, M1) had significantly higher levels of serum BAFF compared to patients with PDAC (p = 0.0182). BAFF was remarkably expressed in infiltrating B lymphocytes surrounding pancreatic cancer in human pancreatic tissues, suggesting that BAFF may play a role in progression of pancreatic cancer. PDAC cell lines were cultured with human recombinant BAFF, and morphology and gene expression were analyzed; pancreatic cancer cells changed to a fibroblast-like morphology, and showed altered gene expression of E-cadherin, vimentin and Snail. These BAFF-induced changes reflect enhanced cell motility and invasion. BAFF-R-overexpressing cell clones confirmed the association between these BAFF-induced changes and epithelial-mesenchymal transition (EMT)-related genes. BAFF was elevated in patients with metastatic advanced PDAC and induced alterations in PDAC cells via regulation of EMT-related genes. Elucidation of the precise role and mechanism of control of BAFF may lead to new therapeutic approaches with the aim of improving pancreatic cancer survival.  相似文献   
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