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1.
El-Hadi Ibrahim Adil Denizli Sema Bekta
mer Gen Erhan Pi
kin 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,720(1-2):217-224
Poly(2-hydroxyethylmethacrylate–ethyleneglycoldimethacrylate) [poly(HEMA–EGDMA)] microspheres carrying Cibacron Blue F3GA and/or thionein were prepared and used for the removal of cadmium ions Cd(II) from human plasma. The poly(HEMA–EGDMA) microspheres, in the size range of 150–200 μm in diameter, were produced by a modified suspension copolymerization of HEMA and EGDMA. The reactive triazinyl dye-ligand Cibacron Blue F3GA was then covalently incorporated into the microspheres. The maximum dye incorporation was 16.5 μmol/g. Then, thionein was bound onto the Cibacron Blue F3GA-incorporated microspheres under different conditions. The maximum amount of thionein bound was 14.3 mg/g. The maximum amounts of Cd(II) ions removed from human plasma by poly(HEMA–EGDMA)–Cibacron Blue F3GA and poly(HEMA–EGDMA)–Cibacron Blue F3GA–thionein were of 17.5 mg/g and 38.0 mg/g, respectively. Cd(II) ions could be repeatedly adsorbed and desorbed with both types of microspheres without significant loss in their adsorption capacity. 相似文献
2.
Waseem Hassan Mohammad Ibrahim Joao Batista Teixeira Rocha 《Chemico-biological interactions》2009,182(1):52-58
As an extension of our previous work we not only evaluated the relationship between acidosis and lipid peroxidation in rat's kidney homogenate, but also determined for the first time the potential anti-oxidant activity of diphenyl diselenide, diphenyl ditelluride and ebselen at a range of pH values (7.4–5.4). Because of the pH dependency of iron redox cycling, pH and iron need to be well controlled and for the reason we tested a number of pH values (from 7.4 to 5.4) to get a closer idea about the role of iron under various pathological conditions. Acidosis increased rate of lipid peroxidation in the absence Fe (II) in kidney homogenates especially at pH 5.4. This higher extent of lipid peroxidation can be explained by; the mobilized iron which may come from reserves where it is weakly bound. Addition of iron (Fe) chelator desferoxamine (DFO) to reaction medium completely inhibited the peroxidation processes at all studied pH values including acidic values (5.8–5.4). In the presence of Fe (II) acidosis also enhanced detrimental effect of Fe (II) especially at pH (6.4–5.4). Diphenyl diselenide significantly protected lipid peroxidation at all studied pH values, while ebselen offered only a small statistically non-significant protection. The highest anti-oxidant potency was observed for diphenyl ditelluride. These differences in potencies were explained by the mode of action of these compounds using their catalytic anti-oxidant cycles. However, changing the pH of the reaction medium did not alter the anti-oxidant activity of the tested compounds. This study provides evidence for acidosis catalyzed oxidative stress in kidney homogenate and for the first time anti-oxidant potential of diphenyl diselenide and diphenyl ditelluride not only at physiological pH but also at a range of acidic values. 相似文献
3.
Theofilos Poutahidis Sean M. Kearney Tatiana Levkovich Peimin Qi Bernard J. Varian Jessica R. Lakritz Yassin M. Ibrahim Antonis Chatzigiagkos Eric J. Alm Susan E. Erdman 《PloS one》2013,8(10)
Wound healing capability is inextricably linked with diverse aspects of physical fitness ranging from recovery after minor injuries and surgery to diabetes and some types of cancer. Impact of the microbiome upon the mammalian wound healing process is poorly understood. We discover that supplementing the gut microbiome with lactic acid microbes in drinking water accelerates the wound-healing process to occur in half the time required for matched control animals. Further, we find that Lactobacillus reuteri enhances wound-healing properties through up-regulation of the neuropeptide hormone oxytocin, a factor integral in social bonding and reproduction, by a vagus nerve-mediated pathway. Bacteria-triggered oxytocin serves to activate host CD4+Foxp3+CD25+ immune T regulatory cells conveying transplantable wound healing capacity to naive Rag2-deficient animals. This study determined oxytocin to be a novel component of a multi-directional gut microbe-brain-immune axis, with wound-healing capability as a previously unrecognized output of this axis. We also provide experimental evidence to support long-standing medical traditions associating diet, social practices, and the immune system with efficient recovery after injury, sustained good health, and longevity. 相似文献
4.
Ibrahim Che Omar Hisashi Saeki Naomichi Nishio Shiro Nagai 《Biotechnology letters》1989,11(3):161-166
Summary The applications of immobilized lipase ofMucor miehei for the synthesis of acetone glycerol acyl ester from acetone glycerol and fatty acid, which is the first step for monoglyceride production was investigated. With a high oleic acid to acetone glycerol ratio (O/A, mol/mol), a high catalytic activity was observed under low water content in the reaction mixture. By the combination of high O/A ratio (>3) and removal of water which was produced during the reaction, the conversion degree was increased to almost 100%. With the O/A ratio of 3, the approximate half-life of the immobilized lipase and productivity of ester was estimated to be 20 days and 869 g product/g immobilized enzyme per 2 half-lives, respectively. 相似文献
5.
Summary Studies with the atypical muscarinic antagonist pirenzepine provide convincing evidence for the classification of muscarinic acetylcholine receptors (mAChRs) into two subtypes, M1 and M2. The present study examines the heterogeneity of the M2 subtype employing the newly developed competitive muscarinic antagonist, AFDX-116. Comparison of the binding affinities of pirenzepine, atropine, and AFDX-116 to mAChRs in microsomes from the rabbit cerebral cortex, heart, and iris smooth muscle shows that iris mAChRs, which are pharmacologically of the M2 subtype, can be distinguished from M2 cardiac receptors based on their affinity for AFDX-116. These results are consistent with the hypothesis that the M2 receptor subtype consists of a heterogeneous population of receptors.Abbreviations mAChRs
Muscarinic Acetylcholine Receptors
- CCh
Carbachol
- NMS
N-Methylscopolamine
- AFDX-116
11-[[2-[(diethylamino)methyl]-1-piperidinyl]acetyl]-5,11-dihydro-6Hpyrido[2,3-b][1,4]benzodiazepine-6-one 相似文献
6.
Spatial Distribution of Flavonoid Conjugates in Relation to Glucosyltransferase and Sulfotransferase Activities in Flaveria bidentis 总被引:2,自引:2,他引:0 下载免费PDF全文
The spatial distribution of sulfated and glucosylated flavonols as well as of the enzymes involved in the later steps of their biosynthesis, sulfotransferase and glucosyltransferase, were investigated in the shoots of Flaveria bidentis. The highest amounts of both types of flavonoid conjugates (as micromole per gram fresh weight) and the highest activities of their enzymes (as picokat per milligram) were detected in the terminal bud and the first pair of leaves. Sulfotransferase activity was also highest in the upper stem segments and in the basal section of the leaves. Western blot analysis of protein extracts showed that variations in sulfotransferase activity in different tissues correlate well with the amounts of immunodetected enzyme protein. These results were discussed in relation to the possible role of conjugated flavonoids in plant growth. 相似文献
7.
8.
The mast cells of the mammalian central nervous system. IX. Development of the mast cells in the brain of the young rat 总被引:1,自引:0,他引:1
M Z Ibrahim 《Acta anatomica》1985,124(3-4):149-158
There are four potentially granular or frankly granular cells within the connective tissue compartment of the mammalian central nervous system, whether this is part of the surface leptomeninges or the leptomeningeal sleeves around parenchymal blood vessels larger than capillaries. These are: Cells that behave like macrophages, part of the mononuclear phagocyte system of the body; they are granular to varying degrees (containing lysosomes). Brown-pigmented granular cells which are mainly located on the surface but are also seen for varying distances along blood vessels as they pass inside the CNS of pigmented animals. Mast cells (MCs) which are granular and located especially prominently in surface leptomeninges of young mammals, and, in adults, are restricted to special parts of the CNS. Granular cells, referred to by me as neurolipomastocytoid cells (NLMs), are numerous, ubiquitously distributed, and seem to have morphological features in common with those of both MCs and macrophages. The exact identity of these NLMs still needs to established. One approach was to study the development of all three non-pigmented cells in the immature brain of the albino rat, especially at the ultrastructural level. This communication represents the findings regarding the MCs. The MCs appear to arise from a small mononuclear cell and to go through maturation stages identical to those described by others for MCs outside the CNS. The greatly flattened adjacent leptomeningeal cells are an easily identifiable entity especially due to their peculiar glycogen content in the young. 相似文献
9.
K. E. Ibrahim M. W. Couch C. M. Williams M. J. Fregly J. M. Midgley 《Journal of neurochemistry》1985,44(6):1862-1867
The development of a radiochemical enzyme assay for p-octopamine in 1969 led to its identification in a large number of invertebrate nerve systems and in mammalian sympathetic nerves. The original method by which p-octopamine was measured has now been found to be nonspecific; however, modifications of this procedure can determine both m- and p-octopamine. We recently developed a new specific method for the unequivocal identification and quantitative determination in tissue of the six octopamine and synephrine isomers. With this method--negative chemical ionization gas chromatography-mass spectrometry--the more physiologically active m-octopamine has been found in association with p-octopamine in 10 organs of the rat. m-Octopamine is present in concentrations equal to those of p-octopamine in heart, spleen, and liver and in concentrations from 30 to 60% of p-octopamine in adrenals, vas deferens, brain, kidney, large intestine, bladder, and lungs. In vivo inhibition of monoamine oxidase markedly increased the concentrations of both m- and p-octopamine in all organs examined. Both amines were virtually absent from all organs except the adrenals following chemical sympathectomy with 6-hydroxydopamine, thereby establishing that m- and p-octopamine are localized within sympathetic nerve endings. 相似文献
10.
A M Ibrahim Y M Shaker M F el-Hawary K I Fayek M M Zahran N K el-Shawarby 《Clinical physiology and biochemistry》1985,3(1):16-22
Total serum protein levels in 70 patients with urolithiasis were not significantly different from those in 20 control subjects, although certain variations were detected in individual protein patterns. In contrast, total urinary protein was significantly higher in patients with urolithiasis. 4-6 different components, i.e., albumin, alpha 1-acidic glycoprotein, alpha 1-antitrypsin, Gc-globulin, fibrinogen and immunoglobulin G, were found in the matrices of calculi and in urine, suggesting that proteinuria may play a role in the formation of stones in patients with urolithiasis. 相似文献