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1.
I. N. Semenchuk L. A. Taranova A. A. Kalenyuk P. V. Il’yasov A. N. Reshetilov 《Applied Biochemistry and Microbiology》2000,36(1):69-72
The operating and storage stability of a receptor element of an amperometric biosensor based on thePseudomonas rathonis strain T capable of degrading surfactants was tested. Microbial cells were immobilized by incorporation in gels (agar, agarose,
and calcium-alginate), polyvinyl alcohol membrane, adhesion to Chromatographic paper GF/A, or by cross-linking induced by
glutaric aldehyde. Incorporation of microbial cells in agar gel provides long-standing conservation of their activity and
viability during measurements of high concentrations of surfactants and allows the receptor element of the biosensor to be
rapidly recovered after measurements. 相似文献
2.
Il Sang Yoon 《Analytical biochemistry》2010,407(2):205-210
Parkinson’s disease (PD) is a neurodegenerative disease featured by selective loss of substantia nigra neurons. Rotenone administration in animals induces neurodegeneration accompanied by α-synuclein-positive Lewy body-like inclusions, recapturing typical histopathological features of PD. In an effort to screen for small-molecule agents to reverse rotenone-induced cytotoxicity, we developed and validated a sensitive and robust assay with neuroblastoma SK-N-SH cells. This assay was amenable to a high-throughput screening format with Z′ factor of 0.56. Robotic screening of a bioactive compound library led to the identification of carnosic acid that can effectively protect cells from rotenone treatment. Using a high-content image-based assay and Western blot analysis, we demonstrated that carnosic acid protects cells from rotenone stress by significant induction of HSP70 expression. Therefore, the assay reported here can be used to identify novel cytoprotective agents for clinical therapeutics of PD. 相似文献
3.
Chang Shin Yoon Eun Gyu Lee Young Seek Lee Il Yup Chung 《Biotechnology and Bioprocess Engineering》1997,2(2):86-89
Epidermal growth factor (EGF) known as a urgastrone is a powerful mitogen with a wide variety of possibilities for medical
usages. A mature EGF coding region was isolated from human prepro-EGF sequence by a conventional PCR and cloned into pQE vector
in which the gene product was supposed to be expressed with 6×His tag for the subsequent purification. The recombinant mature
EGF was expressed in M15[Rep4], anEscherichia coli host strain, in amount of 30–40% of total proteins present inE. coli extract by the addition of isopropylthio-β-galactopyranoside (IPTG). The recombinant EGF purified using a Ni2+-NTA affinity column chromatography was active in its ability to induce phosphorylation on tyrosine residues of several substrate
proteins when murine NIH3T3 and human MRC-5 fibroblast cells were stimulated with it. This work may provide the basic technology
and information for the production of recombinant EGF. 相似文献
4.
Reviewed are works concerning the mechanisms of collagen (type I) fibril packing and the influence of macromolecular structure and physicochemical parameters of the medium on the process. 相似文献
5.
E. V. Suslov T. M. Khomenko I. V. Il’ina D. V. Korchagina N. I. Komarova K. P. Volcho N. F. Salakhutdinov 《Paleontological Journal》2006,40(4):S532-S537
It is shown that natural chiral catalysts, which could be formed e.g., from optically active amino acids on basic natural
minerals, could lead, at early stages of evolution, to the formation of rather complex optically active products from starting
achiral compounds. Using biomimetic combinations of vanadium ion complexes and chiral ligands synthesized from widely occurring
natural compounds, we created novel catalytic systems, permitting the transfer of optical activity in the course of catalytic
chemical transformations of achiral compounds. We found that in the presence of natural clay, optically active terpenoids
from the pinane series undergo multistage transformations, forming unexpected new products with preservation of optical purity. 相似文献
6.
L. A. Taranova I. N. Semenchuk P. V. Il’yasov A. N. Reshetilov 《Applied Biochemistry and Microbiology》2000,36(2):173-176
The dependence of the sensitivity of a microbial biosensor of anionic surfactants (AS) on the growth phase ofPseudomonas rathonis T, a strain capable of degrading surfactants, was studied. Correlations were found between the optimum values of temperature
and pH for microbial growth, substrate utilization, and functional performance of the microbial biosensor. These results allow
the process of AS detection to be optimized. 相似文献
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Discrete models of competitors (initial population and mutants) are considered in which reproduction is set by an increasing and concave function, and migration in the space consisting of a set of areas is described by a Markov matrix. This allows using the theory of monotonic operators to study problems of selection, coexistence and stability. It is shown that the higher is the number of areas, the more severe are the requirements of selective advantage to the initial population. 相似文献
10.
M. A. Abdurakhmanov I. D. Stolyarov A. G. Il’vesa T. L. Tsvetkova V. V. Lebedev 《Human physiology》2006,32(2):154-156
The relationship between the parameters of the distribution of plantar pressure and the state of a patient with multiple sclerosis has been studied with repeated measurements, before and after (or during) treatment. The possibility of using this method for study of walking function impairment in a chronic demyelinating process is considered. 相似文献