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排序方式: 共有275条查询结果,搜索用时 31 毫秒
71.
V M Paralkar A K Nandedkar A H Reddi 《Biochemical and biophysical research communications》1989,160(2):419-424
Subcutaneous implantation of demineralized bone matrix results in bone differentiation. The bone inductive protein, osteogenin, was isolated recently by heparin affinity chromatography. The affinity of osteogenin for various lectins was examined to attain further purification and characterization. Osteogenin extracted from bovine bone matrix binds to concanavalin A (Con A) but not to wheat germ agglutinin or soybean lectin. The present data indicate that the bone inductive protein, osteogenin, is a glycoprotein. The use of a Con A Sepharose affinity column followed by preparative gel electrophoresis resulted in a greater than 250,000 fold purification of osteogenin. 相似文献
72.
Purification and partial amino acid sequence of osteogenin, a protein initiating bone differentiation 总被引:20,自引:0,他引:20
F P Luyten N S Cunningham S Ma N Muthukumaran R G Hammonds W B Nevins W I Woods A H Reddi 《The Journal of biological chemistry》1989,264(23):13377-13380
Osteogenin was purified from bovine bone matrix and its activity monitored by an in vivo bone induction assay. The purification method utilized extraction of the bone-inducing activity with 6 M urea, followed by chromatography on heparin-Sepharose, hydroxyapatite, and Sephacryl S-200. Active fractions were further purified by preparative sodium dodecyl sulfate gel electrophoresis without reduction. Osteogenin activity was localized in a zone between 30 and 40 kDa. The amino acid sequences of a number of tryptic peptides of the gel-eluted material were determined. Reduction and alkylation of purified osteogenin in 7 M guanidine hydrochloride resulted in the total loss of biological activity. Sodium dodecyl sulfate gel electrophoresis under reducing conditions revealed a broad band with an apparent molecular mass of 22 kDa. 相似文献
73.
Naveen Kumar MSc PhD Scholar Srinu Reddi PhD Savita Devi MSc PhD Sanusi Bello Mada PhD Rajeev Kapila PhD Suman Kapila PhD 《Journal of cellular biochemistry》2019,120(6):9677-9691
Prolonged passaging of primary fibroblast cells totally shapes the natural biological phenomena and leads to the appearance of features related to senescence. As a result, it is a good natural tool to delineate the molecular mechanism of cellular aging. The present investigation revealed the antiaging effect of milk-derived novel bioactive peptide (VLPVPQK). The peptide played an important role in downregulating apoptosis-related markers in late passages of cultured fibroblast cells. The peptide treatment to aged fibroblasts caused enhancement in cell migration, DNA integrity, and decrease in the lipid peroxidation, reactive oxygen species, nitric oxide production as well as pro-inflammatory cytokines, TNF-α and IL-6. Moreover, the peptide decreased the expression of apoptotic caspases, Bax, and senescence-associated β-galactosidase (SA-β-gal) proteins. The peptide pretreatment also enhanced the extracellular collagen protein and antiapoptotic, Bcl-xL. In addition, the peptide treatment reversed the senescence-related activity in fibroblasts by stimulating Nrf2 mediated antioxidative defense system and inhibiting the action of NFkB/p38MAPK signaling, similar to the commercially available inhibitor (SB203580) of p38MAPK. Thus, the peptide exhibits the antiaging effect in dermal fibroblast cells. 相似文献
74.
K K Reddi 《Biochemical and biophysical research communications》1976,68(4):1119-1125
Human granulocytes contain an RNase which is thermostable at pH 4.2 and thermolabile at pH 8.5. It has a pH optimum at 6.5. It exhibits highest preference for the secondary phosphate esters of uridine 3′-phosphates. It has no action on uridine 2′: 3′-cyclic phosphates. Poly (A) and poly (G) are inert to its action. Its rate of hydrolysis of poly (C) is about 1% of that of poly (U). It differs from bovine pancreatic RNase and human serum RNase. Because of its unique specificity, this enzyme might serve as a biochemical marker in certain granulocyte disorders. 相似文献
75.
76.
Phytoremediation of selenium using transgenic plants 总被引:1,自引:0,他引:1
77.
The influence of oxygen tension on the side population (SP) fraction sorted from ATDC5 chondroprogenitor cells was investigated. ATDC5 cells cultured in normoxia (20%) or hypoxia (1% oxygen) were compared. The SP fraction was significantly higher in the cells cultured in hypoxia. The gene expression of 3 ABC transporters, abcb1a/b (mdr1a/b) and abcg2 (bcrp1) was quantified by RT-PCR. SP cells were characterized by the higher expression of abcb1a. The expression levels of abcb1b and abcg2 were higher than abcb1a. However, there was no significant difference between SP and non-SP fractions in the expression of abcb1b and abcg2. The telomeric repeat amplification protocol assay showed that SP cells tended to show lower telomerase activity than non-SP cells. Chondrogenic properties of ATDC5 cells derived from SP or non-SP were assessed by micromass culture. There were not significant differences between SP and non-SP derived cells in Alcian blue staining and sox9, Aggrecan, Col2a1 and SZP mRNA expression. The results demonstrate that the SP fraction was stimulated by hypoxia and chondrogenic properties of SP and non-SP fraction of ATDC5 cells were similar. 相似文献
78.
79.
Robson Sartorello Alexandre Budu Piero Bagnaresi Carlos AH Fernandes Paloma M. Sato Vânia B. Bueno Marcos RM Fontes Pedro L. Oliveira Gabriela O. Paiva‐Silva Simone V. Alves Luis ES Netto Luiz H. Catalani Celia RS Garcia 《Cell biology international》2010,34(8):859-865
The cellular traffic of haem during the development of the human malaria parasite Plasmodium falciparum, through the stages R (ring), T (trophozoite) and S (schizonts), was investigated within RBC (red blood cells). When Plasmodium cultures were incubated with a fluorescent haem analogue, ZnPPIX (Zn protoporphyrin IX) the probe was seen at the cytoplasm (R stage), and the vesicle‐like structure distribution pattern was more evident at T and S stages. The temporal sequence of ZnPPIX uptake byP. falciparum‐infected erythrocytes shows that at R and S stages, a time‐increase acquisition of the porphyrin reaches the maximum fluorescence distribution after 60 min; in contrast, at the T stage, the maximum occurs after 120 min of ZnPPIX uptake. The difference in time‐increase acquisition of the porphyrin is in agreement with a maximum activity of haem uptake at the T stage. To gain insights into haem metabolism, recombinant PfHO (P. falciparum haem oxygenase) was expressed, and the conversion of haem into BV (biliverdin) was detected. These findings point out that, in addition to haemozoin formation, the malaria parasite P. falciparum has evolved two distinct mechanisms for dealing with haem toxicity, namely, the uptake of haem into a cellular compartment where haemozoin is formed and HO activity. However, the low Plasmodium HO activity detected reveals that the enzyme appears to be a very inefficient way to scavenge the haem compared with the Plasmodium ability to uptake the haem analogue ZnPPIX and delivering it to the food vacuole. 相似文献
80.
Arjan D van Zuilen Ingeborgh van der Tweel Peter J Blankestijn Michiel L Bots Marjolijn van Buren Marc AGJ ten Dam Karin AH Kaasjager Peter JG van de Ven Gerald Vervoort Louis-Jean Vleming Gerry Ligtenberg Jack FM Wetzels 《Trials》2006,7(1):1-9