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1.
Reprod Med Biol ; 21(1): e12432, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386368

RESUMO

Purpose: Early rescue intracytoplasmic sperm injection (ICSI) is often performed in cases in which not even a single oocyte has extruded a second polar body 6 h after insemination. We evaluated the usefulness of expanding the indications of early rescue ICSI to cases in which <80% of oocytes have extruded second polar bodies 6 h after insemination. Methods: Early rescue ICSI was performed on oocytes that were denuded 2.5 h post-insemination and whose extrusion of the second polar bodies had been examined 6 h post-insemination with a PolScope. Results: In vitro fertilization was performed on 24 496 oocytes of 4944 cycles, and 1438 cycles had <80% rate of the second polar body extrusion. Rescue ICSI was performed on 3933 oocytes. Three pronuclei (3PN) incidence of rescue ICSI was 3.0% in oocytes with ≥50% rate of the second polar body extrusion. With respect to the second polar body extrusion rate, no differences were observed in normal fertilization, blastocyst development, implantation, miscarriage, or live birth rates for rescue ICSI. Conclusion: By expanding the indications of early rescue ICSI using the PolScope to cases in which <80% of oocytes have extruded the second polar bodies, many fertilized oocytes can be obtained without considerably increasing the 3PN rate.

2.
J Assist Reprod Genet ; 38(5): 1061-1068, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33619678

RESUMO

PURPOSE: When rescue artificial oocyte activation (ROA) is performed on the day after intracytoplasmic sperm injection (ICSI) or later, embryonic development is poor and seldom results in live births. The efficacy of an early ROA after ICSI is unclear. Is early ROA effective in rescuing unfertilized oocytes that have not undergone second polar body extrusion several hours after ICSI? METHODS: We performed retrospective cohort study between October 2016 and September 2019, targeting 2891 oocytes in 843 cycles when ICSI was performed. We performed ROA with calcium ionophore on 395 of the 475 oocytes with no second polar extrusion 2.5-6 h after ICSI. RESULTS: The normal fertilization rate of ROA oocytes was significantly higher than non-ROA oocytes (65.8% vs 6.7%, P < 0.001). The blastocyst development rate in ROA oocytes was significantly lower than spontaneously activated oocytes (48.9% vs 67.2%, P < 0.001). The ROA oocyte implantation rate did not significantly differ from the spontaneously activated oocytes (36.0% vs 41.2%). We observed no differences in the implantation rates and blastocyst development rates over the 2.5-6 h from ICSI until ROA. CONCLUSION: Early ROA is effective, and the optimal timing appears to be 2.5-6 h after ICSI.


Assuntos
Desenvolvimento Embrionário/genética , Fertilização in vitro , Nascido Vivo/epidemiologia , Oócitos/crescimento & desenvolvimento , Blastocisto/efeitos dos fármacos , Ionóforos de Cálcio/farmacologia , Implantação do Embrião/genética , Transferência Embrionária/tendências , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Humanos , Masculino , Oócitos/efeitos dos fármacos , Corpos Polares/efeitos dos fármacos , Corpos Polares/metabolismo , Injeções de Esperma Intracitoplásmicas/tendências
3.
Cancer Sci ; 108(5): 1049-1057, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28256037

RESUMO

CUB domain-containing protein-1 (CDCP1) is a trans-membrane protein predominantly expressed in various cancer cells and involved in tumor progression. CDCP1 is phosphorylated at tyrosine residues in the intracellular domain by Src family kinases and recruits PKCδ to the plasma membrane through tyrosine phosphorylation-dependent association with the C2 domain of PKCδ, which in turn induces a survival signal in an anchorage-independent condition. In this study, we used our cell-free screening system to identify a small compound, glycoconjugated palladium complex (Pd-Oqn), which significantly inhibited the interaction between the C2 domain of PKCδ and phosphorylated CDCP1. Immunoprecipitation assays demonstrated that Pd-Oqn hindered the intercellular interaction of phosphorylated CDCP1 with PKCδ and also suppressed the phosphorylation of PKCδ but not that of ERK or AKT. In addition, Pd-Oqn inhibited the colony formation of gastric adenocarcinoma 44As3 cells in soft agar as well as their invasion. In mouse models, Pd-Oqn markedly reduced the peritoneal dissemination of gastric adenocarcinoma cells and the tumor growth of pancreatic cancer orthotopic xenografts. These results suggest that the novel compound Pd-Oqn reduces tumor metastasis and growth by inhibiting the association between CDCP1 and PKCδ, thus potentially representing a promising candidate among therapeutic reagents targeting protein-protein interaction.


Assuntos
Proliferação de Células/efeitos dos fármacos , Metástase Neoplásica/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Proteína Quinase C-delta/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Células A549 , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
BMC Cancer ; 13: 237, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23672493

RESUMO

BACKGROUND: Cisplatin (CDDP) is the most frequently used chemotherapeutic agent for various types of advanced cancer, including gastric cancer. However, almost all cancer cells acquire resistance against CDDP, and this phenomenon adversely affects prognosis. Thus, new chemotherapeutic agents that can overcome the CDDP-resistant cancer cells will improve the survival of advanced cancer patients. METHODS: We synthesized new glycoconjugated platinum (II) and palladium (II) complexes, [PtCl2 (L)] and [PdCl2 (L)]. CDDP-resistant gastric cancer cell lines were established by continuous exposure to CDDP, and gene expression in the CDDP-resistant gastric cancer cells was analyzed. The cytotoxicity and apoptosis induced by [PtCl2 (L)] and [PdCl2 (L)] in CDDP-sensitive and CDDP-resistant gastric cancer cells were evaluated. DNA double-strand breaks by drugs were assessed by evaluating phosphorylated histone H2AX. Xenograft tumor mouse models were established and antitumor effects were also examined in vivo. RESULTS: CDDP-resistant gastric cancer cells exhibit ABCB1 and CDKN2A gene up-regulation, as compared with CDDP-sensitive gastric cancer cells. In the analyses of CDDP-resistant gastric cancer cells, [PdCl2 (L)] overcame cross-resistance to CDDP in vitro and in vivo. [PdCl2 (L)] induced DNA double-strand breaks. CONCLUSION: These results indicate that [PdCl2 (L)] is a potent chemotherapeutic agent for CDDP-resistant gastric cancer and may have clinical applications.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Glicoconjugados/farmacologia , Paládio/uso terapêutico , Platina/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Expressão Gênica/efeitos dos fármacos , Genes p16 , Glicoconjugados/química , Glicoconjugados/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Paládio/farmacologia , Platina/farmacologia , Regulação para Cima
5.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): m208, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346872

RESUMO

In the title compound, [Sn(C(20)H(19)N(2)O(3))Cl(3)], the Sn(IV) ion is surrounded by a tridentate monoanionic Schiff base and by three meridional chloride ions in a six-coordinated distorted octa-hedral geometry. The Sn-Cl bond [2.366 (2) Å] trans to nitro-gen is shorter than the others [2.438 (2) and 2.414 (2) Å]. The N-Sn-N angle [76.19 (11)°] is smaller than the O-Sn-N angle [87.89 (10)°] in the Schiff base ligand. No classical inter-molecular hydrogen-bonding inter-actions are observed. The crystal packing exhibits π-π stacking inter-actions, with a distance of 3.595 (2) Šbetween the centroids of the phenolate ring and the benzene ring of the quinoline group of inversion-related mol-ecules.

6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): o3380, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22199871

RESUMO

In the title compound, C(16)H(10)Br(2)N(2)O·H(2)O, bifurcated intra-molecular N-H⋯(N,O) hydrogen bonding defines the essential planarity of the main mol-ecule: the dihedral angle between the quinoline and benzene rings is 7.53 (8)°. Inter-molecular O-H⋯O and weak C-H⋯O hydrogen bonds consolidate the crystal packing, which exhibits π-π inter-actions with a distance of 3.588 (1) Šbetween the centroids of the aromatic rings and short Br⋯Br contacts of 3.5757 (6) Å.

7.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 5): m573, 2010 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-21579054

RESUMO

The structure of the title compound, [Mo(2)(C(4)H(8)NO(2)S)(2)O(2)S(2)], has been redetermined. Besides obvious differences between the original [Drew & Kay (1971 ▶). J. Chem. Soc. A, pp. 1851-1854] and the current unit-cell parameters, some packing features of the structure are also different; these findings are the result of significant improvements in the precision and accuracy of the present structure analysis. The two Mo atoms in the dimeric complex have very similar distorted trigonal-bipyramidal environments. Each Mo atom is bonded to an S atom and to an N atom of an l-cysteine ester ligand, to a terminal O atom and to two S atoms which bridge to the adjacent Mo atom [Mo⋯Mo separation = 2.8191 (2) Å]. N-H⋯O(carbon-yl) and N-H⋯O(terminal) hydrogen-bonding inter-actions consolidate the crystal packing. During the synthesis, the originally employed l-cysteinate ligand has been converted to the l-cysteinate methyl ester ligand. Since this reaction does not take place without tin(IV) chloride, it is clear that tin(IV) chloride acts as a catalyst for the reaction.

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): o429, 2010 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-21579844

RESUMO

The main mol-ecule of the title methanol solvate, C(16)H(10)Cl(2)N(2)O·CH(3)OH, exists in the keto form and the C=O and N-H bonds are mutually cis in the crystal structure. The dihedral angle between the quinoline and benzene rings is 11.17 (3)°. A bifurcated intra-molecular N-H⋯(O,N) hydrogen bond is present as well as an O-H⋯O hydrogen bond. In the crystal, C-H⋯O inter-actions link the 3,5-dichloro-salicyl-idene-8-amino-quinoline and methanol mol-ecules.

9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): o1892, 2010 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-21588227

RESUMO

The mol-ecule of the title compound, C(16)H(11)N(3)O(3), exists in the keto form and the C=O and N-H bonds are mutually cis in the crystal structure. There are two crystallographically independent mol-ecules per asymmetric unit with broadly similar structural data. The only noticeable difference between the two is the dihedral angles between the benzene and the quinoline rings: 1.04 (4) and 3.07 (4)°. In the structure, intra-molecular N-H⋯O(carbon-yl) and N-H⋯N(pyridine) hydrogen bonds exist but there is no evidence of formal inter-molecular hydrogen-bonding associations.

10.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): o3127, 2009 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-21578850

RESUMO

The mol-ecule of the title compound, C(21)H(16)N(2)O, exists in the keto form and the C=O and N-H bonds are mutually cis in the crystal structure, although an enol form would be possible through tautomerism. The dihedral angle between the quinoline and the naphthalene systems is 22.04 (2)°. A bifurcated intramolecular N-H⋯(O,N) hydrogen bond is present.

11.
Artigo em Inglês | MEDLINE | ID: mdl-18926735

RESUMO

A case of squamous cell carcinoma presumed to have arisen from the right Stensen duct is reported. The patient, a 62-year-old man, was referred to our hospital with swelling in the right cheek. Magnetic resonance imaging (MRI), including contrast-enhanced MRI, and contrast-enhanced computerized tomography (CECT) enabled diagnosis of a solitary mass in the Stensen duct. Fat-suppressed T(2)-weighted imaging, in particular, demonstrated a mass-like lesion in the dilated Stensen duct and obstructive parotitis where the duct transitions into the parotid gland. Gadolinium-DTPA-enhanced T(1)-weighted imaging demonstrated the mass-like lesion surrounded by signal-hyperintense layer showing continuous transition from the thickened Stensen duct wall, which was also hyperintense. The CECT revealed peripheral annular enhancement surrounding the tumorous mass, with no enhancement of the duct wall itself, reflecting an increase in micro blood vessels in the stroma of the neoplasm. These image findings correlated well with subsequent histopathologic findings. A mass with rim enhancement and dilated Stensen duct accompanied by parotitis and no salivary calculus may suggest a differential diagnosis of malignant tumor of Stensen duct.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Parotídeas/patologia , Ductos Salivares/patologia , Carcinoma de Células Escamosas/irrigação sanguínea , Meios de Contraste , Diagnóstico Diferencial , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/irrigação sanguínea , Parotidite/diagnóstico , Tomografia Computadorizada por Raios X/métodos
12.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): m605-6, 2008 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-21202165

RESUMO

The title compound, [Mo(2)Zn(C(3)H(5)NO(2)S)(2)O(2)S(2)(H(2)O)(2)], forms a one-dimensional chain. The cysteine S atom of the dinuclear molybdenum complex anion coordinates to the zinc ion, which has a tetra-hedral environment by the additional coordination of two water mol-ecules. The one-dimensional chains are connected to each other by hydrogen bonds. The Zn-S(cysteine) distances [2.3599 (6) and 2.3072 (6) Å] are close to the value in ZnS (2.35 Å). The distances and angles within the complex are very close to those reported for the sodium and potassium di-µ-sulfide species.

13.
Inorg Chem ; 46(2): 357-9, 2007 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-17279807

RESUMO

A seven-electron cluster [Mo3(mu3-S){mu3-SC(CO(2)CH(3))=C(CO(2)CH(3))S}{mu-SC(CO(2)CH(3))=CH(CO(2)CH(3))}(dtp)3(mu-OAc)] [2, S2P(OC(2)H(5))2-; dtp = diethyldithiophosphate] and an organometallic cluster [Mo3(mu3-S){mu3-SC(CO(2)CH(3))=C(CO(2)CH(3))S}{mu-SC(CO(2)CH(3))CH(OCH(3))(CO2)}(dtp)2(CH(3)OH)(mu-OAc)](Mo-C) (3) were obtained by reaction in methanol of the sulfur-bridged trinuclear complex [Mo3(mu3-S)(mu-S)3(dtp)3(CH(3)CN)(mu-OAc)] (1) with dimethylacetylenedicarboxylate (DMAD). The X-ray structures of 2 and 3 revealed the adduct formation of two DMAD molecules to the respective Mo(3)S(4) cores. 2 is paramagnetic and obeys the Curie-Weiss law: the mu(eff) value at 300 K is 1.90 muB. The electron spin resonance signal was observed at 173 K. The density functional theory calculation of 2 demonstrated that the main components of the singly occupied molecular orbitals of alpha and beta spins are Mo d electrons and the main components of lowest unoccupied molecular orbitals are of Mo and the olefin moiety with one C-S bond. A one-electron reversible oxidation process of 2 was observed at E1/2 = -0.11 V vs Fc/Fc+. The electronic spectrum of 2 has a peak at 468 nm (epsilon = 2170 M(-1) cm(-1)) and shoulders at 640 (918) and 797 (605) nm, and 3 has shoulders at 441 (1740) and 578 (625) nm and a distinct peak at 840 (467) nm. An intermediate [Mo3(mu3-S){mu3-SC(CO(2)CH(3))=C(CO(2)CH(3))S}{mu-SC(CO(2)CH(3))=CH(CO(2)CH(3))}(dtp)3(mu-OAc)]+ (4) is tentatively suggested: a one-electron reduction of 4 gives 2, and a nucleophilic conjugate addition of CH(3)O- to the alpha,beta-unsaturated carbonyl group of 4 gives 3.

14.
Physiol Chem Phys Med NMR ; 39(2): 259-68, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-19256355

RESUMO

Aluminum ion was administered orally to mice for a long period (80 weeks). Aluminum, magnesium, and calcium in the urine were measured weekly, and aluminum in organs, i.e., brain, kidney, liver, heart, lung, and bone, was measured in the final stage. Calcium in the bones was also measured. The results of the urine tests suggest that aluminum ion is hardly absorbed by mice if it is dosed alone. Aluminum ion administered with glycine or glutamic acid is accumulated in vivo, but the presence of tryptophane has little influence on aluminum incorporation. When aluminum remains in the body, the calcium and magnesium excretions increase. The long-term administration of aluminum resulted in the accumulation of aluminum in all organs. The amount of aluminum increased distinctly in all organs. It notably increased when aluminum was dosed with either glycine or glutamic acid. Special attention should be paid to the fact that aluminum amounts in the brain and bones are very high when dosed with either glycine or glutamic acid.


Assuntos
Alumínio/administração & dosagem , Ácido Glutâmico/administração & dosagem , Glicina/administração & dosagem , Triptofano/administração & dosagem , Alumínio/metabolismo , Alumínio/urina , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cálcio/metabolismo , Cálcio/urina , Sinergismo Farmacológico , Feminino , Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Magnésio/metabolismo , Magnésio/urina , Camundongos , Miocárdio/metabolismo , Distribuição Tecidual/efeitos dos fármacos
15.
Inorg Chem ; 45(14): 5429-37, 2006 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-16813406

RESUMO

The reaction of [Mo3S4(H2O)9]4+ (1) with hydrotris(pyrazolyl)borate (Tp) ligands produced [Mo3S4Tp3]Cl x 4 H2O ([3]Cl x 4 H2O) in an excellent yield. An X-ray structure analysis of [3]Cl x 4 H2O revealed that each molybdenum atom bonded to the Tp ligand. We report four salts of 3, [3]Cl x 4 H2O, [3]tof x 2 H2O, [3]PF6 x H2O, and [3]BF4 x 2 H2O in this paper. The solubility and stability of the chloride salt in organic solvents differ completely from those of the other salts. We have also prepared a new compound, [Mo3OS3Tp3]PF6 x H2O ([4]PF6 x H2O), via the reaction of [Mo3OS3(H2O)9]4+ (2) with KTp in the presence of NH4PF6. All the molybdenum atoms bonded to Tp ligand. 1H NMR signals corresponding to nine protons bonded to three pyrazole rings in one Tp were observed in a spectrum (at 253 K) of [3]BF4 x 2 H2O. It shows that cluster 3 has a 3-fold rotation axis in CD2Cl2 solution. Twenty-one 1H NMR signals corresponding to twenty-seven protons bonded to nine pyrazole rings in three Tp ligands were observed in a spectrum (at 233 K) of [4]PF6 x H2O; obviously, 4 has no 3-fold rotation axis, in contrast to 3. The short CH...mu3S distance caused large upfield chemical shifts in the 1H NMR spectra of 3 and 4. The reaction of 3 with metallic iron in CH2Cl2 produced [Mo3FeS4XTp3] (X = Cl (5), Br (6)). X-ray structure analysis of 5 has revealed the existence of a cubane-type core Mo3FeS4. Complex 3 functions as a metal-complex ligand for preparing a novel mixed-metal complex even in nonaqueous solvents. The cyclic voltammogram of 5 shows two reversible one-electron couples (E(1/2) = -1.40 and 0.52 V vs SCE) and two irreversible one-electron oxidation processes (E(pc) = 1.54 and 1.66 V vs SCE).

16.
Inorg Chem ; 44(10): 3494-8, 2005 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-15877431

RESUMO

The reaction of [Mo(3)S(4)(H(2)O)(9)](4+) (1) with [(CpRhCl(2))(2)] afforded a novel rhodium-molybdenum cluster, [{Mo(3)RhCpS(4)(H(2)O)(7)(O)}(2)](8+) (2). X-ray structure analysis of [2](pts)(8).14H(2)O (pts(-) = CH(3)C(6)H(4)SO(3)(-)) has revealed the existence of a new oxo-bridged twin cubane-type core, (Mo(3)RhCpS(4))(2)(O)(2). The high affinity of the CpRh group for sulfur atoms in 1 seems to be the main driving force for this reaction. The strong Lewis acidity of the CpRh group in intermediate A, [Mo(3)RhCpS(4)(H(2)O)(9)](6+), caused a release of proton from one of the water molecules attached to the molybdenum atoms to give intermediate B, [Mo(3)RhCpS(4)(H(2)O)(8)(OH)](5+). The elimination of two water molecules from two intermediate B molecules, followed by the deprotonation reaction of hydroxo bridges, generated the twin cubane-type cluster 2. The formal oxidation states of rhodium and molybdenum atoms are the same before and after the reaction (i.e., Mo(IV)(3), Rh(III)). The Mo-O-Mo moieties in [2](pts)(8).14H(2)O are nearly linear with a bond angle of 164.3(3) degrees, and the basicity of the bridging oxygen atoms seems to be weak. For this reason, protonation at the bridging oxygen atoms does not occur even in a strongly acidic aqueous solution. The binding energy values of Mo 3d(5/2), Rh 3d(5/2), and C 1s obtained from X-ray photoelectron spectroscopy measurements for [2](pts)(8).14H(2)O are 229.8, 309.3, and 285 eV, respectively. The XPS measurements on the Rh 3d(5/2) binding energy indicate that the oxidation state of Rh is 3+. The binding energy of Mo 3d(5/2) (229.8 eV) compares with that observed for [1](pts)(4).7H(2)O (230.7 eV, Mo 3d(5/2)). A lower energy shift (0.9 eV) is observed in the binding energy of Mo 3d(5/2) for [2](pts)(8).14H(2)O. This energy shift may correspond to the coordination of an oxygen atom having a negative charge to the molybdenum atom.

17.
Physiol Chem Phys Med NMR ; 37(1): 65-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16583993

RESUMO

The evidence implicating aluminum as a neurotoxin is mounting. Research with animals and humans has linked aluminum with neuro-cognitive dysfunction and, in some cases, death. Although the relationship between aluminum intake and Alzheimer's disease is still unclear, some experts have recently issued a strong warning that human exposure to aluminum should be limited. The results indicate that the amount of aluminum decreased in the urine in mice that were administered glycine or glutamic acid together with aluminum ion. In the mice in which the amounts of aluminum decreased in the urine, the amount of calcium conversely increased.


Assuntos
Alumínio/administração & dosagem , Alumínio/urina , Doença de Alzheimer/metabolismo , Aminoácidos/administração & dosagem , Cálcio/urina , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/patologia , Aminoácidos/metabolismo , Animais , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Glicina/administração & dosagem , Glicina/metabolismo , Glicina/farmacologia , Camundongos , Neurotoxinas/metabolismo
18.
Inorg Chem ; 43(2): 602-12, 2004 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-14731022

RESUMO

Reactions are reported of sulfur-bridged incomplete cubane-type tungsten clusters having W(3)(micro(3)-S)(micro-S)(3) cores with acetylene and its derivative dimethylacetylenedicarboxylate (DMAD). The reaction of the isothiocyanate tungsten cluster [W(3)(micro(3)-S)(micro-S)(3)(NCS)(9)](5)(-) (5) with acetylene in 0.1 M HCl afforded a novel complex having two acetylene molecules in different adduct formation modes, [W(3)(micro(3)-S)(micro(3)-SCH=CHS)(micro-SCH=CH(2))(NCS)(9)](4)(-) (6), and the presence of two kinds of intermediates [W(3)(micro(3)-S)(micro-S)(micro(3)-SCH=CHS)(NCS)(9)](5)(-) (7) and [W(3)(micro(3)-S)(micro-S)(2)(micro-SCH=CH(2))(NCS)(9)](4)(-) (8) was observed. The reaction of the diethyldithiophosphate (dtp) tungsten cluster [W(3)(micro(3)-S)(micro-S)(3)(micro-OAc)(dtp)(3)(CH(3)CN)] (10) with DMAD in acetonitrile containing acetic acid resulted in the formation of another complex having two DMAD molecules of different adduct formation modes, [W(3)(micro(3)-S)(micro-SC(CO(2))=CH(CO(2)CH(3)))(micro(3)-SC(CO(2)CH(3))=C(CO(2)CH(3))S)(micro-OAc)(dtp)(3)] (11), where hydrolysis of one of the four ester groups of the two DMAD groups occurred and the resultant carboxylic group coordinated to tungsten. The conformation of the micro-SCH=CH(2) moiety in 6 is different from that of the corresponding moiety in [W(3)(micro(3)-S)(micro-O)(micro-S)(micro-SCH=CH(2))(NCS)(9)](4)(-) (4). Introduction of the second acetylene molecule to the intermediate [W(3)(micro(3)-S)(micro-S)(2)(micro-SCH=CH(2))(NCS)(9)](4)(-) (8) resulted in the formation of 6. The clusters were characterized by UV-vis spectroscopy, (1)H NMR spectroscopy, and X-ray crystallography (for (Hpy)(4).6.1.33py.0.5H(2)O and 11.CH(3)CN), and the formation of 6 and 11 was examined in detail from a mechanistic point of view.

19.
Inorg Chem ; 42(4): 935-7, 2003 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-12588120

RESUMO

A photochromic complex with disulfur and dimethyl-ethylene-1,2-dithiolate ligands, [Mo(2)(mu-S(2))(mu-S(2)C(2)Me(2))(2)(S(2)C(2)Me(2))(2)] (3), was synthesized and characterized. Photoirradiation of 3 with visible light resulted in the formation of the isomer (3'). The electronic spectrum of 3' has a new intense peak in the near infrared region, and in the dark, the spectrum returns to that of 3. X-ray structural analyses of 3.C(6)H(6) and 3' revealed a large conformational change of the bridging dithiolate ligands: the two ligands in 3' come very close to each other compared to those in 3.C(6)H(6). Crystal data: 3.C(6)H(6), monoclinic, space group C2/c, a = 15.193(4) A, b = 14.287(3) A, c = 14.685(4) A, beta = 105.30(1) degrees, V = 3074(1) A(3), Z = 4; 3', monoclinic, space group C2/c, a = 21.5400(8) A, b = 9.5232(5) A, c = 13.9828(2) A, beta = 118.924(1) degrees, V = 2510.5(2) A(3), Z = 4. (1)H NMR spectra of 3 (3.06, 3.05, 1.66, and 1.31 ppm) and 3' (2.90, 2.75, 2.14, and 1.97 ppm) are also reported: each spectrum has four signals due to methyl groups, which accords well with the fact that each of the molecules, 3.C(6)H(6) and 3', has a crystallographic 2-fold axis.

20.
Physiol Chem Phys Med NMR ; 34(1): 83-90, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12403277

RESUMO

The extracorporeal excretion of mercury from the organs by [Mo3S4(Hnta)3]2- (referred to as the NTA complex) solution was investigated using mice exposed to metallic mercury vapor. A decrease in mercury levels was seen in the organs of mice that were administered NTA complex solution when compared to organs in mice receiving L-cysteine or water. Moreover, in mice that were administered NTA complex solution, mercury level in the kidneys decreased at the third and fifth days following mercury exposure. These results suggest that NTA complex solution has the effect of releasing mercury in the living-body as seen when mercury levels are compared with those in the organs of mice that were administered L-cysteine or water.


Assuntos
Cisteína/administração & dosagem , Mercúrio/sangue , Mercúrio/farmacocinética , Administração por Inalação , Animais , Encéfalo/metabolismo , Hidrocarbonetos Aromáticos com Pontes , Feminino , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Mercúrio/administração & dosagem , Mercúrio/análise , Camundongos , Camundongos Endogâmicos ICR , Miocárdio/metabolismo , Especificidade de Órgãos , Compostos Organometálicos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
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