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1.
A unique multibranched cyclomaltooligosaccharide (cyclodextrin, CD) of 6(1),6(3),6(5)-tri-O-alpha-maltosyl-cyclomaltoheptaose [6(1),6(3),6(5)-tri-O-alpha-maltosyl-beta-cyclodextrin, (G(2))(3)-betaCD] was prepared. The physicochemical and biological properties of (G(2))(3)-betaCD were determined together with those of monobranched CDs (6-O-alpha-D-glucopyranosyl-alpha-cyclodextrin (G(1)-alphaCD), 6-O-alpha-D-glucopyranosyl-beta-cyclodextrin (G(1)-betaCD), and 6-O-alpha-maltosyl-beta-cyclodextrin (G(2)-betaCD)). NMR spectra of (G(2))(3)-betaCD were measured using various 2D NMR techniques. The solubility of (G(2))(3)-betaCD in water and MeOH-water solutions was extremely high in comparison with nonbranched betaCD and was about the same as that of the other monobranched betaCDs. The formation of an inclusion complex of (G(2))(3)-betaCD with stereoisomers (estradiol, retinoic acid, quinine, citral, and glycyrrhetinic acid) depends on the cis-trans isomers of guest compounds. The cis isomers of estradiol, retinoic acid, and glycyrrhetinic acid were included more than their trans isomers, while the trans isomers of citral and quinine fit more tightly than their cis isomers. (G(2))(3)-betaCD was the most effective host compound in the cis-trans resolution of glycyrrhetinic acid. Among the branched betaCDs, (G(2))(3)-betaCD exhibited the weakest hemolytic activity in human erythrocytes and showed negligible cytotoxicity in Caco-2 cells up to 200 microM. These results indicate unique characteristics of (G(2))(3)-betaCD in some biological responses of cultured cells.  相似文献   

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Summary The serum groups Gm(1) [Gm(a)], Gm(2) [Gm(x)], Gm(4) [Gm(f)]. Gm(12) [Gm(b)] and Inv(1) [Inv(1)] of 2000 sera of healthy blood donors from the land Hesse were examined. The results obtained were compared with those known until now. Three persons, not related to each other, possessed the extremely rare phenotype Gm(-1, 2, 4, 12) [Gm (a-x+b+f+)]. In 0.75% of the cases we found a discordant behaviour of the factors Gm(4) and Gm(12) [Gm(f) and Gm(b)].
Zusammenfassung 2000 Seren von gesunden Blutspendern aus Hessen wurden bezüglich der Gamma-Globulin-Serumgruppen Gm(1) [Gm(a)], Gm(2) [Gm(x)], Gm(4) [Gm(f)]. Gm(12) [Gm(b)] und Inv(1) [Inv(1)] untersucht. Die gefundenen Resultate wurden mit den bisher bekannten verglichen. Drei miteinander nicht verwandte Personen wiesen den äußerst seltenen Phänotyp Gm(-1, 2, 4, 12) [Gm(a-x+b+f+)] auf. In 0.75% der Fälle fanden wir ein diskordantes Verhalten der Faktoren Gm(4) und Gm(12) [Gm(f) und Gm(b)].


Director: Prof. Dr. W. Wachsmuth

Director: Prof. Dr. W. Spielmann

The nomenclature suggested by WHO at a round-table conference over genes, genotypes and allotypes of immunglobulins is used. The conference took place in Geneva on the 1965 31. 5. to the 5. 6. [5].

With technical assistance of S. Mohs.  相似文献   

4.
New solid complex compounds of La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III) and Gd(III) ions with morin were synthesized. The molecular formula of the complexes is Ln(C15H9O7)3 · nH2O, where Ln is the cation of lanthanide and n = 6 for La(III), Sm(III), Gd(III) or n = 8 for Ce(III), Pr(III), Nd(III) and Eu(III). Thermogravimetric studies and the values of dehydration enthalpy indicate that water occurring in the compounds is not present in the inner coordination sphere of the complex. The structure of the complexes was determined on the basis of UV-visible, IR, MS, 1H NMR and 13C NMR analyses. It was found that in binding the lanthanide ions the following groups of morin take part: 3OH and 4CO in the case of complexes of La, Pr, Nd, Sm and Eu, or 5OH and 4CO in the case of complexes of Ce and Gd. The complexes are five- and six-membered chelate compounds.  相似文献   

5.
《Inorganica chimica acta》1986,117(2):187-189
The isolation and characterization of nine polymeric complexes of the general formula [M(L)1.5S2]n (where M is the metal ion, L the ligand and S the solvent, C2H5OH) of La(III) and Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Ho(III) with.the biologically active compound embelin using elemental and thermal analysis, infrared and electronic spectral studies is reported.  相似文献   

6.
N-(2-Pyridyl)acetamide (aapH) complexes of palladium(II), cobalt(II), nickel(II), and copper(II) have been studied by means of magnetic susceptibilities, and infrared, electronic, and PMR spectra. In the octahedral complexes M(aapH)2X2(M = Co, Ni, Cu; X = Cl, Br, NCS, NO3), bidentate aapH is chelated through the pyridine-N and amid-O atomes, whereas in the square-planar Pd(aapH)2X2 (X = Cl, Br) unidentate aapH is coordinated through the pyridine-N atom alone. Under alkaline conditions aapH is deprotonated in the presence of palladium(II) to form Pd(aap)2·4H2O, aap being an anionic bidentate ligand and chelating through the pyridine-N and amide-O atoms.  相似文献   

7.
The 4-hydroxysalicylidenechitosan Schiff-base (2CS-Hdhba) was prepared by the condensation of 2,4-dihydroxybenzaldehyde with chitosan, and its metal complexes, [M(2CS-dhba)Cl2(H2O)2] (M(III) = Fe, Ru, Rh), [M′(2CS-dhba)(AcO)(H2O)2] (M′(II) = Co, Ni, Cu, Zn), [Pd(2CS-dhba)Cl(H2O)] and [Au(2CS-dhba)Cl2], are reported. These complexes were characterized by elemental analysis, by spectral data (FTIR, solid-phase 13C NMR, UV–vis and ESR spectroscopy), by morphological observations (SEM and XRD), and by magnetic and thermal measurements. The Schiff base (2CS-Hdhba) behaves as a bidentate chelate with a single negative charge. The azomethine nitrogen and the deprotonated 2-hydroxy centres with the pendant glucosamine hydroxy functionality play no role in coordination. The dissociation constants of 2CS-Hdhba and the stability constants of some of its metal complexes have been determined pH-metrically.  相似文献   

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Background

Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem.

Results

The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively.

Conclusions

Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.  相似文献   

10.
Methanobactin (mb) is a novel chromopeptide that appears to function as the extracellular component of a copper acquisition system in methanotrophic bacteria. To examine this potential physiological role, and to distinguish it from iron binding siderophores, the spectral (UV–visible absorption, circular dichroism, fluorescence, and X-ray photoelectron) and thermodynamic properties of metal binding by mb were examined. In the absence of Cu(II) or Cu(I), mb will bind Ag(I), Au(III), Co(II), Cd(II), Fe(III), Hg(II), Mn(II), Ni(II), Pb(II), U(VI), or Zn(II), but not Ba(II), Ca(II), La(II), Mg(II), and Sr(II). The results suggest metals such as Ag(I), Au(III), Hg(II), Pb(II) and possibly U(VI) are bound by a mechanism similar to Cu, whereas the coordination of Co(II), Cd(II), Fe(III), Mn(II), Ni(II) and Zn(II) by mb differs from Cu(II). Consistent with its role as a copper-binding compound or chalkophore, the binding constants of all the metals examined were less than those observed with Cu(II) and copper displaced other metals except Ag(I) and Au(III) bound to mb. However, the binding of different metals by mb suggests that methanotrophic activity also may play a role in either the solubilization or immobilization of many metals in situ.  相似文献   

11.
Electrospray ionization mass spectrometry (ESI-MS) of mixtures containing glutathione (GSH) and nitrates, oxides or chlorides of the heavy metals, arsenic, antimony, cadmium, mercury, thallium, lead or bismuth allows for definitive identification of complexes in the gas phase. In the positive ion mode, spectra show prominent m/z peaks that are assigned to monocations of general formulae [E(GSH)-xH]+ (E = Cd, Hg, Tl, Pb, As, Sb or Bi; x = 0, 1 or 2), [E(GSH)2-xH]+ (E = Hg, As, Sb, or Bi; x = 1 or 2), [E(GSH)3-xH]+ (E = As, Sb or Bi; x = 2), [E2(GSH)-xH]+ (E = Tl or Pb; x = 1 or 3), [E2(GSH)2-xH]+ (E = Bi; x = 5), [E2(GSH)3-xH]+ (E = Bi; x = 5), and/or [E3(GSH)-xH]+ (E = Tl; x = 2). Spectra obtained in the negative ion mode give m/z peaks observed in assigned to monoanionic species that correspond to some of the monocationic species listed above with two protons removed. The results demonstrate the potential application of ESI-MS as a versatile and efficient approach to study toxic heavy metals in biological systems. In addition, the observations provide a foundation database to understand the chemistry of these heavy metals with bio-molecules.  相似文献   

12.
Metal complexes of d-glucose (d-Glc) from large cation containing dibromo-dichloro salts of dipositive metals [NEt4]2[MBr2Cl2] (M = Mn, Co, Ni, Cu and Zn) and the disodium salt of glucose were synthesized from a MeOH:MeCN mixture. The complexes were characterized by UV-vis absorption, circular dichroism, IR and proton magnetic resonance spectroscopies, and by elemental analysis, and were found to be Na[M(d-Glc)(OMe)Cl]. Cyclic voltammetric studies of these complexes, in the acidic to neutral pH range, indicated no dissociation, even in highly acidic conditions.This paper is dedicated to Professor Richard H. Holm (Harvard University) on the occasion of his 60th birthday.  相似文献   

13.
Methanobactin (mb) is a novel chromopeptide that appears to function as the extracellular component of a copper acquisition system in methanotrophic bacteria. To examine this potential physiological role, and to distinguish it from iron binding siderophores, the spectral (UV–visible absorption, circular dichroism, fluorescence, and X-ray photoelectron) and thermodynamic properties of metal binding by mb were examined. In the absence of Cu(II) or Cu(I), mb will bind Ag(I), Au(III), Co(II), Cd(II), Fe(III), Hg(II), Mn(II), Ni(II), Pb(II), U(VI), or Zn(II), but not Ba(II), Ca(II), La(II), Mg(II), and Sr(II). The results suggest metals such as Ag(I), Au(III), Hg(II), Pb(II) and possibly U(VI) are bound by a mechanism similar to Cu, whereas the coordination of Co(II), Cd(II), Fe(III), Mn(II), Ni(II) and Zn(II) by mb differs from Cu(II). Consistent with its role as a copper-binding compound or chalkophore, the binding constants of all the metals examined were less than those observed with Cu(II) and copper displaced other metals except Ag(I) and Au(III) bound to mb. However, the binding of different metals by mb suggests that methanotrophic activity also may play a role in either the solubilization or immobilization of many metals in situ.  相似文献   

14.
A new ligand N-salicyloyl-N'-o-hydroxythiobenzhydrazide (H2Sotbh) forms complexes [Mn(HSotbh)2], [Fe(Sotbh-H)(H2O)2], [M(Sotbh)] [M=Co(II), Cu(II) and Zn(II)] and [Ni(Sotbh)(H(2)O)2], which were characterized by various physico-chemical techniques. M?ssbauer spectrum of [Fe(Sotbh-H)(H2O)2] reveals the quantum admixture of 5/2 and 3/2 spin-states. Mn(II), Cu(II) and Ni(II) complexes were observed to inhibit the growth of tumor in vitro, whereas, Fe(III), Co(II), Zn(II) complexes did not. In vivo administration of Mn(II), Cu(II) and Ni(II) resulted in prolongation of survival of tumor bearing mice. Tumor bearing mice administered with Mn(II), Cu(II) and Ni(II) complexes showed reversal of tumor growth associated induction of apoptosis in lymphocytes. The paper discusses the possible mechanisms and therapeutic implication of the H2Sotbh and its metal complexes in tumor regression and tumor growth associated immunosuppression.  相似文献   

15.
Synthesis and physical-chemistry characterization of five new genuine complex compounds of 1-Benzylidine-2-phenazinoylhydrazine with Pd(II), Pt(II), Ni(II), Hg(II) and Cu(I) are presented. The chemical structure for these complexes is suggested by the elemental chemical analysis, molecular mass measurements, electric conductivities as well as by IR and UV-VIS spectra. The metal:ligand molar ratio is found 1:1, the obtained complexes belonging to the square planar geometry D4h.  相似文献   

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The potentiometric and spectroscopic methods were applied to describe the equilibria for the Cu(II), Ni(II), and Co(II), D-galactosamine solutions. The stability constants, the spectral data, and the results obtained earlier precisely defined the binding ability of the aminosugars.  相似文献   

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Previous studies indicate that 11,12,15-trihydroxyeicosatrienoic acid (11,12,15-THETA), an endothelium-derived hyperpolarizing factor in the rabbit aorta, mediates a portion of the relaxation response to acetylcholine by sequential metabolism of arachidonic acid by 15-lipoxygenase, hydroperoxide isomerase, and epoxide hydrolase. To determine the stereochemical configuration of the endothelial 11,12,15-THETA, its activity and chromatographic migration were compared with activity and migration of eight chemically synthesized stereoisomers of 11,12,15(S)-THETA. Of the eight isomers, only 11(R),12(S),15(S)-trihydroxyeicosa-5(Z),8(Z),13(E)-trienoic acid comigrated with the biological 11,12,15-THETA on reverse- and normal-phase HPLC and gas chromatography. The same THETA isomer (10(-7)-10(-4) M) relaxed the rabbit aorta in a concentration-related manner (maximum relaxation = 69 +/- 5%). These relaxations were blocked by apamin (10(-7) M), an inhibitor of small-conductance Ca2+-activated K+ channels. In comparison, 11(S),12(R),15(S),5(Z),8(Z),13(E)-THETA (10(-4) M) relaxed the aorta by 22%. The other six stereoisomers were inactive in this assay. With use of the whole cell patch-clamp technique, it was shown that 10(-4) M 11(R),12(S),15(S),5(Z),8(Z),13(E)-THETA increased outward K+ current in isolated aortic smooth muscle cells by 119 +/- 36% at +60 mV, whereas 10(-4) M 11(R),12(R),15(S),5(Z),8(Z),13(E)-THETA increased outward K+ current by only 20 +/- 2%. The 11(R),12(S),15(S),5(Z),8(Z),13(E)-THETA-stimulated increase in K+ current was blocked by pretreatment with apamin. These studies suggest that 11(R),12(S),15(S)-trihydroxyeicosa-5(Z),8(Z),13(E)-trienoic acid is the active stereoisomer produced by the rabbit aorta. It relaxes smooth muscle by activating K+ channels. The specific structural and stereochemical requirements for K+ channel activation suggest that a specific binding site or receptor of 11,12,15-THETA is involved in these actions.  相似文献   

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