Nickel is absorbed mainly through the lungs and gastrointestinal tract. Once in the body it enters the bloodstream, where it binds to albumin, L-histidine, and _2-macroglobulin. Nickel tends to accumulate in the lungs, thyroid, kidney, heart, and liver. Absorbed nickel is excreted in the urine, wherease unabsorbed nickel is excreted in the faeces. (L41)
Nickel is known to substitute for other essential elements in certain enzmes, such as calcineurin. It is genotoxic, and some nickel compounds have been shown to promote cell proliferation. Nickel has a high affinity for chromatin proteins, particularly histones and protamines. The complexing of nickel ions with heterochromatin results in a number of alterations including condensation, DNA hypermethylation, gene silencing, and inhibition of histone acetylation, which have been shown to disturb gene expression. Nickel has also been shown to alter several transcription factors, including hypoxia-inducible transcription factor, activating transcription factor, and NF-KB transcription factor. There is also evidence that nickel ions inhibit DNA repair, either by directly inhibiting DNA repair enzymes or competing with zinc ions for binding to zinc-finger DNA binding proteins, resulting in structural changes in DNA that prevent repair enzymes from binding. Nickel ions can also complex with a number of cellular ligands including amino acids, peptides, and proteins resulting in the generation of oxygen radicals, which induce base damage, DNA strand breaks, and DNA protein crosslinks. (L41, A40)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
致癌性证据
A4:无法归类为人类致癌物。/镍,可溶性无机化合物(NOS),作为镍/
A4: Not classifiable as a human carcinogen. /Nickel, soluble inorganic compounds (NOS), as Ni/
Evaluation: There is sufficient evidence in humans for the carcinogenicity of nickel sulfate, and of the combinations of nickel sulfides and oxides encountered in the nickel refining industry. There is inadequate evidence in humans for the carcinogenicity of metallic nickel and nickel alloys. There is sufficient evidence in experimental animals for the carcinogenicity of metallic nickel, nickel monoxides, nickel hydroxides and crystalline nickel sulfides. There is limited evidence in experimental animals for the carcinogenicity of nickel alloys, nickelocene, nickel carbonyl, nickel salts, nickel arsenides, nickel antimonide, nickel selenides and nickel telluride. There is inadequate evidence in experimental animals for the carcinogenicity of nickel trioxide, amorphous nickel sulfide and nickel titanate. The Working Group made the overall evaluation on nickel compounds as a group on the basis of the combined results of epidemiological studies, carcinogenicity studies in experimental animals, and several types of other relevant data, supported by the underlying concept that nickel compounds can generate nickel ions at critical sites in their target cells. Overall evaluation: Nickel compounds are carcinogenic to humans (Group 1). Metallic nickel is possibly carcinogenic to humans (Group 2B). /Nickel compounds/
The most common harmful health effect of nickel in humans is an allergic reaction. This usually manifests as a skin rash, although some people experience asthma attacks. Long term inhahation of nickel causes chronic bronchitis and reduced lung function, as well as damage to the naval cavity. Ingestion of excess nickel results in damage to the stomach, blood, liver, kidneys, and immune system, as well as having adverse effects on reproduction and development. (L41)
Synthesis, complexation, and X-ray structure of a new type of binucleating macrocycle incorporating both soft and hard ligating sites
作者:Catherina J. van Staveren、David N. Reinhoudt、Johan van Eerden、Sybolt Harkema
DOI:10.1039/c39870000974
日期:——
A macrocyclic ligand with both a Schiff base moiety and a polyether cavity forms mono- and bi-nuclear complexes; X-ray analysis of the mononuclear Ba(ClO4)2 complex shows that Ba2+ is co-ordinated in the polyether cavity.
Toner, charge-imparting material and composition containing metal complex
申请人:Canon Kabushiki Kaisha
公开号:US04673631A1
公开(公告)日:1987-06-16
A triboelectrically chargeable composition for use in development of electrostatic latent images. The composition contains a metal complex of an amino acid compound having an amino or mono-substituted amino group and a carboxylic group. The composition is embodied typically as a positively chargeable toner and also as a charge-imparting material for charging a toner.
Production and use of imines of porphyrins, of porphyrin derivatives and
申请人:The University of Toledo
公开号:US05424305A1
公开(公告)日:1995-06-13
Purified imines of porphyrins, chlorins, bateriochlorins, chlorophylls, bacteriochlorophylls, purpurins, reduced purpurins, verdins, Diels Alder adducts, benzochlorins and metal complexes of the foregoing imines are disclosed for retarding growth of cancer tumors such as bladder tumors. The formulas of the benzochlorinimines and of the benzochlorinimine metal complexes are set forth below: ##STR1## In specific examples, M in the metal complexes is a copper cation that is complexed with two of the nitrogens of the benzochlorinimine R' and R"" are methyl, and R1 through R8 are ethyl.
A process for the preparation of complex salts with additional coordinated ligands comprising reacting with through mixing at 20.degree. to 200.degree. C. a complex-forming metal salt of a metal of the second and third main groups of the Periodic Table and the subgroups thereof with a stoichiometric amount of at least one member of the group consisting of a chelating ligand and a Lewis base in the absence of a solvent according to the equation: M.sub.m.sup.a+ (SR.sup.b-)n+xL.multidot.cH+yB.sup.- .fwdarw.m[M.sup.a+ (SR.sup.b-)(n-o)L.sub.x B.sub.y ]+o.multidot.SR.sup.b- +c.multidot.H.sup.+I wherein M is a metal ion, SR is an acid radical of an organic or inorganic acid, B is a Lewis base, and L is a chelating ligand, m.multidot.a=b.multidot.(n-o)+c.multidot.x, wherein a=an integer of 1-8, b=an integer of 1-3, c=an integer of 0-4, m=an integer of 1-3, n=an integer of 1-8, o=an integer of 0-8, x=an integer of 0-4, y=and integer of 1-16, wherein (n-o)+x+y.ltoreq.16 and the complex salts formed thereby useful as latent curing catalysts.
Selective blocking of some amino groups in a polyamino organic compound having at least one pair of available neighboring hydroxyl and amino groups is effected by first preparing in situ transition metal salt complexes of available neighboring amino and hydroxyl group pairs in said polyamino organic compound, followed by introduction of blocking groups on the non-complexed amino groups and, finally, removing the transition metal cations from the selectively N-blocked polyamino organic compound complex to obtain a polyamino organic compound having selectively blocked amino groups. This process is particularly valuable when carrying out aminocyclitol-aminoglycoside transformations utilizing transition metal salt complexes of cupric acetate, nickel (II) acetate, cobalt (II) acetate or mixtures thereof.