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Seyed Sajad Mohseni Salehi Monfared Shirin Pournourmohammadi 《Biological trace element research》2010,133(2):236-241
Islet transplantation has become a promising treatment in the therapy of type 1 diabetes. Its function improvement, after
isolation and before transplantation, is crucial because of their loss both in number and function of islets after isolation
procedures. Trace elements sodium orthovanadate (SOV) and sodium molybdate (SM), as well as medicinal plant Teucrium polium L. (TP), showed and possessed high beneficial antioxidative potential and even hypoglycemic properties via their effect on
islets. We evaluated the effect of these components in combination on cultured islet function in order to improve pancreatic
islet transplantation. Rat pancreatic islets were cultured for 24 h then incubated with different concentrations of TP (0.01
and 0.1 mg/mL) alone and in combination with SOV (1 mM) or SM (1 mM). Insulin concentration in buffer media was measured as
islet secretory function. Administration of TP (0.01 mg/mL), SM, and SOV alone or in combination with each other significantly
increased insulin secretion at high glucose concentration (16.7 mM); insulin secretion was significantly greater in the group
containing both TP and SM than other treated groups (p < 0.05). The combination of the mentioned trace elements especially molybdate with TP could improve islet cells function before
transplantation. 相似文献
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One novel approach for the biological delivery of peptide drugs is to incorporate the sequence of the peptide into the structure of a natural transport protein such as human serum transferrin (HST). However, a potential drawback is that the HST may increase the immunoreactivity of the peptide, in the same way that carrier proteins can be used to generate highly immunogenic peptide hapten conjugates. In this study we have generated a recombinant HST carrier protein that contains a peptide substrate of HIV-1 protease (VSQNYPIVL). The protein retained native HST function, and the peptide was surface exposed since it was immunoreactive in native dot blots, and was cleaved by HIV-1 protease. Immunisation of rabbits with the recombinant protein elicited only a very poor anti-peptide immune response. In contrast, strong anti-peptide immune responses were raised against both the peptide alone, and a chemical conjugate of the peptide with HST. These data demonstrate that it is possible to attenuate the immune response normally directed against an immunogenic peptide sequence by engineering into a surface exposed loop of HST. These findings may have an important impact on the future design of peptide delivery systems. 相似文献
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Mingyue Wang Pranab K Mukherjee Jyotsna Chandra Ali Abdul Lattif Thomas S McCormick Mahmoud A Ghannoum 《BMC microbiology》2008,8(1):31
Background
We have previously shown that supernatant from Candida albicans (CA) culture contains a Secretory Interleukin (IL)-12 Inhibitory Factor (CA-SIIF), which inhibits IL-12 production by human monocytes. However, the effect of CA-SIIF on secretion of other cytokines by monocytes is unknown, and detailed characterization of this factor has not been performed. 相似文献7.
The glucocorticoid receptor (GR) from mouse AtT-20 pituitary tumor cells, when transformed using a variety of in vitro protocols, yields a DNA-binding RNA-containing 6 S form. In order to better understand the physiological role of RNA interaction with the transformed GR, we have isolated and purified the putative RNA from AtT-20 cells. [3H]Triamcinolone acetonide-labeled cytosolic GR was transformed, using Sephadex G-25 filtration, to yield the RNA-containing 6 S GR. The transformed 6 S GR was separated on DEAE-cellulose into the 4 S GR (eluting at about 100 mM KCl) while its associated RNA eluted at 0.30-0.45 M KCl. The addition of only these RNA fractions to the 4 S GR can reconstitute 6 S GR as shown on 5-20% sucrose gradients. RNA (0.3-0.45 M KCl fractions) was further purified by hydroxylapatite chromatography, and the bound RNA (eluted at approximately 70 mM PO4(-2)) was then loaded onto preparative 5-20% sucrose gradients to separate RNA on the basis of size (sedimentation rate). A uniform class of RNA sedimenting at 4 S was obtained and then adsorbed to oligo(dT)-cellulose columns. The unbound fraction (poly(A-)) was capable of shifting 4 S GR to 6 S. Using these chromatographic procedures about 90% of the cellular RNA, incapable of reconstituting the 6 S GR from the 4 S form, was eliminated. The 4 S GR was covalently cross-linked with the purified RNA (termed PIVB RNA) using formaldehyde. The resulting cross-linked GR X RNA complexes were shown to sediment at the density of ribonucleoprotein (1.38 g/cm3) in CsCl gradients and at the 6 S position in high salt sucrose gradients. The hydrolysis of PIVB RNA with ribonuclease A prevented the formation of high salt-resistant ribonucleoprotein complexes, indicating that the GR may be in close contact with PIVB RNA. Electrophoresis of the PIVB RNA on 5% agarose-formaldehyde-denaturing gels yielded one major band with a molecular size of approximately 75 bases. It thus appears that an endogenous 4 S RNA (PIVB RNA) of about 25 kDa specifically interacts with the monomeric 4 S GR to yield the 6 S GR. 相似文献
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J M Al-Hassan M Afzal M Ali M Thomson T Fatima S Fayad R S Criddle 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,85(1):41-47
Lipids associated with a threat induced epidermal gel secretion from the catfish, Arius thalassinus, have been analyzed. Phospholipids, neutral lipids and glycolipids are all present and each of these subclasses has been analyzed by thin layer and gas chromatography with a general similarity with membrane lipids being noted. The epidermal gel lipids differed from total liver lipids of the catfish. Fatty acid analysis showed the gel lipid to be rich in the unsaturated fatty acids: oleate (omega 7, C18:1), arachidonate (omega 6, C20:4), and docosahexaenoate (omega 3, C22:6). Some prostaglandins were quantitated in lipid extracts from the epidermal gel. 相似文献
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M. A. Akbar 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(3):465-468
Summary Natural rapeseed (Brassica napus L.; AACC 2n=38), originated in the temperate climate of the Southwest European Mediterranean region, fails to complete its generative phase in the subtropics and is thus not cultivated in countries like Bangladesh. Adapted agroecotypes are available from the diploid representatives of its genome A (B. campestris/pekinensis, 2n=20) and C (B. oleracea/alboglabra, 2n=18). An artificial resynthesis based on carefully selected progenitor lines was expected to give a photoperiodically better adapted rapeseed. B. pekinensis x B. oleracea/alboglabra gave 2 hybrids and 87 matromorphous plants from 1,448 crossed flowers and the reciprocal combination gave no hybrid but 11 matromorphous plants from 2,228 pollinated flowers. The two true hybrids were vegetatively propagated and chromosome doubled. Part of the F2 was grown in Sweden (all plants flowered and the most early ones were selected), part in Bangladesh (13 out of 706 plants flowered). The selected F3 material flowered in Bangladesh and transgressions in earliness could be recorded, some lines were of definite agronomic potential. A correlation in earliness between reaction in Sweden (long day) and Bangladesh (short day) was observed. 相似文献