(n.) A substance, in the form of reddish brown, microscopic, prismatic crystals, formed from dried blood by the action of strong acetic acid and common salt; -- called also Teichmann's crystals. Chemically, it is a hydrochloride of hematin.
Example Sentences:
(1) The appearance of an abundant class of polyribosomes was correlated with globin synthesis by demonstrating that a discrete class of polyribosomes arises in cells treated with the inducers hexamethylene bisacetamide and hemin.
(2) Finding (d) indicates that steps involved in the restorative effect of these compounds may not contribute to the stimulation of the globin synthesis in hemin-deficient lysates.
(3) The destabilization of the red cell membrane skeleton in the presence of crude iHCR is caused by release of hemin, which lowers the stability of membrane skeleton by weakening the spectrin-protein 4.1-actin interaction.
(4) Hemin failed to increase P450 levels previously depressed by TPA indicating that TPA acts by lowering apocytochrome levels.
(5) Prior exposure of the adherent cell layer to high concentrations of hemin (10 microM) was found to have a beneficial effect on the support of newly seeded cultures; however, the effect of lower hemin concentrations (0.1-1 microM) on stromal cell layer formation was not significant.
(6) Hemin increased satellite cell fusion by 27%, but decreased cell proliferative rate by 30%.
(7) Inhibition of hemin-mediated O2 activation by bovine superoxide dismutase and the copper tetrammine complex has been examined.
(8) Upon incubation of the HCI preparation with hemin (5-10 microM), the eIF-2 alpha kinase is converted into an inactive form and appears to become associated with related peptides forming high molecular weight complexes which can be reversibly activated by 2-mercaptoethanol.
(9) When the prorepressor is converted to the hemin-controlled translational repressor, either by prolonged warming in the absence of hemin or by incubation with N-ethylmaleimide for 5 min, and then incubated briefly with [gamma-32P]-ATP and Mg2+, a protein that migrates as a 100 000 molecular weight component on sodium dodecyl sulfate-polyacrylamide gels becomes phosphorylated.
(10) Its activity is independent of cyclic AMP as well as of the calcium-dependent regulator protein and is inhibited by hemin.
(11) The spin-labeled hemins were recombined with apoproteins of hemoglobin (Hb), myoglobin (Mb), cytochrome c peroxidase (EC 1.11.1.5) and horseradish peroxidase (EC 1.11.1.7).
(12) A model compound with similar optical properties to the CO-ligated protein can be prepared in dimethyl sulfoxide from hemin chloride, imidazole, and CO using chromous acetate as the heme reductant.
(13) Porphyromonas gingivalis is capable of in vitro growth when iron sources are either complexed to hemin or host iron transport proteins, or exist in an inorganic form.
(14) An assumption is advanced that the P. vitale catalase contains two hemin groups located in two protein subunits.
(15) The effect of hemin administration on the level of hepatic delta-amino-levulinate synthase mRNA was also examined.
(16) We were not able to detect any reaction between the radical (see article) and the hemin group (which would result in a complex such as heme O-2).
(17) The N-acetylimidazole-reacted apoprotein supplemented with hemin and reacted with hydroperoxides, neither showed electronic absorption spectra of higher oxidation states nor an EPR doublet signal due to a tyrosyl radical.
(18) With iron porphyrins (hemin, heme and their complexes) the charge of the iron and the nature of axial ligands determine the position and intensity of the O-bands in the MOR spectrum.
(19) Since S. typhimurium LT2 is not able to incorporate hemin, the identification of the mutants not stimulated by Delta-ALA was made on the basis of the simultaneous loss of catalase activity and cytochromes.
(20) Hemin, known to inactivate IRF in vivo, showed a similar, reversible effect in vitro, presumably by oxidizing IRF.
Humin
Definition:
(n.) A bitter, brownish yellow, amorphous substance, extracted from vegetable mold, and also produced by the action of acids on certain sugars and carbohydrates; -- called also humic acid, ulmin, gein, ulmic or geic acid, etc.
Example Sentences:
(1) Within the years, a variability of the pure humin substances could be detected, depending on the rotation of crops and C-content.
(2) The cranial segment of the uterus forms a balloon-like enlargement at the time of implantation, and the antimesometrial part of its huminal slit expands into a spacious implantation chamber.
(3) All results may be distrubed by humin-and non-humin substances and any metabolism of microorganisms, which of course is especially noticable in damp humas soil.