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21.
Insulin Binding in Four Regions of the Developing Rat Brain 总被引:6,自引:5,他引:1
Specific insulin binding has been demonstrated in partially purified membranes prepared from four regions of the developing rat brain. Insulin binding to brain membranes demonstrated kinetics and hormonal specificity that were quite similar to those reported for traditional insulin target tissues (e.g., liver and adipose tissue), and binding was significantly correlated with receptor concentration. Binding in the olfactory bulbs, cerebrum, cerebellum, and hypothalamus all reached highest values at 15 days of postnatal life, with the olfactory bulbs generally showing the greatest binding at all ages studied. A temporal relationship was found between insulin binding to brain membranes in the postnatal rat and plasma membrane protein synthesis, especially in the cerebellum and olfactory bulbs. 相似文献
22.
23.
24.
R A Memon C Mohan P J Geiger S P Bessman K S Rogers 《Biochemical medicine and metabolic biology》1989,42(3):216-219
Rat liver hepatocytes isolated from a 30-31% percoll density gradient at 10,000g are refractory toward insulin stimulation of 14CO2 formation and 14C-incorporation into protein from [2,3-14C]succinate. Basal hepatocyte oxidation of succinate was not impaired by the presence of 5% percoll in the incubation medium nor was it impaired when percoll-free hepatocytes were used that had been isolated after centrifugation at 9000g; however, in both instances the stimulatory effect of insulin was lost. Hepatocyte damage may have occurred in these processes. This is in contrast to previous work which shows that insulin (10 mU/ml) will stimulate [2,3-14C]succinate oxidation and [2,3-14C]succinate carbon incorporation into protein in non-percoll-treated hepatocytes (isolated by centrifugation at 10g) by about 29%. We conclude that the latter procedure although more time consuming is the more gentle method of choice and leaves the hepatocyte in a form more closely related to an in vivo state than does treatment with a percoll density gradient at 10,000g. 相似文献
25.
Study of the gametocytocidal/sporontocidal action of qinghaosu (artemisinin) by electron microscopy 总被引:1,自引:0,他引:1
The gametocytocidal efficacy of artemisinin (qinghaosu) was evaluated and scanning electron microscopical evidence is given for gametocytocidal action of a single 5-10-mg/kg dose of artemisinin against simian malarial parasite (Plasmodium cynomolgi B). No sporontocidal effect of artemisinin was observed. 相似文献
26.
Inhibition of HIV replication by naphthalenemonosulfonic acid derivatives and a bis naphthalenedisulfonic acid compound 总被引:1,自引:0,他引:1
Several naphthalenemonosulfonic acid analogs and a bis naphthalenedisulfonic acid have been evaluated for anti-HIV activity in assays using H9 and MOLT-3 cells. Among the naphthalenemonosulfonic acids, a 4-amino-5-hydroxy compound and a 4,5-diamino compound showed low anti-HIV activity (upto 50% inhibition) at non-toxic doses. The bis naphthalenedisulfonic acid compound demonstrated significant suppression of HIV-1 antigen expression as measured by monoclonal antibodies to p17 (95%), p24 (94%) and syncytia inhibition (82%) at a dose of 20 micrograms/ml that was non-toxic to the host cells. The bis naphthalenedisulfonic acid analog represents a new class of compounds which may be effective in the treatment of HIV infected patients. The structure activity relationship and a probable mode of action of these compounds is discussed. 相似文献
27.
Mice bearing the H-2
bhaplotype are susceptible to the development of experimental autoimmune myasthenia gravis (EAMG), induced by acetylcholine receptor (AChR) autoimmunity. One of the genes influencing EAMG susceptibility has been mapped to the A
blocus of the major histocompatibility complex, and the A chain has been implicated in the pathogenesis. Mice of the H-2
bhaplotype, including C57BL/10 (B10), have a genomic deletion of the E
gene and therefore fail to express the E molecule on their cell surface. To test the hypothesis that failure to express the cell surface E molecule in B10 mice contributes to EAMG pathogenesis, E
inf
supk
transgenic B10 mice expressing the T molecule were examined. Expression of the E molecule in E
inf
supk
transgenic B10 mice partially prevented the development of EAMG. 相似文献
28.
PCR-based DNA markers linked to a gall midge resistance gene, Gm4t, has potential for marker-aided selection in rice 总被引:3,自引:0,他引:3
S. Nair A. Kumar M. N. Srivastava M. Mohan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(6):660-665
Rice DNAs from a gall midge resistant variety, Abhaya, a susceptible variety, Tulsi and their F3 progeny were screened using 500 random primers in conjunction with bulked-segregant analysis in a polymerase chain reaction (PCR) with a view to detecting random amplified polymorphic DNAs (RAPDs) linked to the gene, Gm4t, which confers resistance to gall midge, a dipteran insect pest of rice. A total of 454 primers were able to produce a distinct amplification pattern, and 3695 bands/loci were amplified between the phenotypically different parents. Of these, 304 bands were polymorphic between the parents, with 19 being phenotypespecific. One of these primers, E20, amplified 2 bands, E20570 and E20583, which are tightly linked to resistance and susceptibility, respectively. These specific bands were cloned and sequenced, and a 94% sequence homology was found between the two fragments. Two specific 20-mer oligonucleotides were synthesized, based on the sequence information of E20583, for use in PCR amplification directly from genomic DNAs. These PCR primers were able to amplify phenotype-specific bands, a 583-bp fragment in susceptible F3 lines and a 570-bp fragment in resistant F3 lines that had been derived from a cross between the parents, indicating their potential and utility for marker-aided selection of the Gm4t gene in rice. Its use would facilitate the early and efficient selection of resistant genes in plant breeding programmes and even in those areas where the insect is not known to occur. These phenotype-specific bands are single-copy sequences and are being mapped to ascertain their chromosomal location in rice. 相似文献
29.
Anusha Parthiban Selvamani Vijayalingam K. Radha Shanmugasundaram Rema Mohan 《Cell biology international》1995,19(12):987-994
Erythrocytes isolated from 131 cases of Non-Insulin Dependent Diabetes Mellitus (NIDDM) were studied for lipid peroxidation, antioxidant defences, and the maximum peroxidisable substrate in the cell membrane. Antioxidant defences are lowered in NIDDM, followed by significant rise in lipid peroxidation products. However, in the erythrocyte membrane, the total polyunsaturated peroxidisable lipids are lower than in normal erythrocytes which may be a causative factor affecting the survival of the cells. 相似文献
30.
The polymerase chain reaction (PCR) has developed into one of the most promising methods for in vitro enzymatic amplification of DNA and has found widespread application in DNA cloning, sequencing and mutagenesis related studies. This innovative technique can selectively amplify a single target DNA molecule a billion-fold in a span of a few hours. Amplification of specific DNA sequences by PCR is useful in identification of sex, novel genes, pathogens and diseases. PCR has facilitated the establishment of evolutionary relationships among species and in revealing structural intricacies of single cells. In this article we review some of the major advances and applications of PCR, especially, its role in embryo sexing. 相似文献