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1.
BMC Oral Health ; 23(1): 708, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789315

RESUMO

BACKGROUND: The effects of oral health on mortality have been reported; however, the association between mortality and Oral Health-Related Quality of Life (OHQOL) is unknown. We investigated the effect of OHQOL on total mortality in a cohort consisting of dentists. METHODS: In this cohort study, we analyzed data from the Longitudinal Evaluation of Multi-phasic, Odonatological and Nutritional Associations in Dentists study. We conducted a baseline survey of general and oral health factors. We called for 31,178 participants and collected responses from 10,256 participants. We followed up with 10,114 participants (mean age ± standard deviation, 52.4 ± 12.1 years; females, 8.9%) for 7.7 years, until March 2014, to determine the average total mortality. OHQOL was assessed using the General Oral Health Assessment Index (GOHAI). The total score was divided into quartiles (Q1 ≤ 51.6, Q2 = 51.7-56.7, Q3 = 56.8-59.9, and Q4 = 60.0), with higher GOHAI scores indicating better OHQOL (score range, 12-60). The association between OHQOL and total mortality was analyzed using the Cox proportional hazards model. RESULTS: We documented 460 deaths. Males with low GOHAI scores possessed a remarkably high risk of total mortality. The multivariate adjusted-hazard ratios (aHRs), were 1.93 (95% confidence interval [CI], 1.07 - 3.48) for Q1, 1.69 (95% CI, 0.90 - 3.17) for Q2, and 0.65 (95% CI, 0.29 - 1.46) for Q3, relative to Q4 (trend p = 0.001). The aHRs in the multivariate model with all background variables were 1.69 (95% CI, 1.15-2.46) for Q1, 1.53 (95% CI, 1.04-2.27) for Q2, and 1.09 (95% CI, 0.71-1.70) for Q3, relative to Q4 (trend p = 0.001). In females, there was no significant association between the quartiles, in both the multivariate-adjusted model (trend p = 0.52) and multivariate-adjusted model with all background variables (trend p = 0.79). CONCLUSIONS: A lower OHQOL indicated an increased risk of total mortality in dentists. OHQOL may be used as an indicator for selecting treatment plans and personalized care interventions, thus contributing to increased healthy life expectancy. TRIAL REGISTRATION: Aichi Cancer Center, Nagoya University Graduate School of Medicine, and Hiroshima University (Approval numbers: 33, 632-3, 8-21, and E2019-1603).


Assuntos
Saúde Bucal , Qualidade de Vida , Masculino , Feminino , Humanos , Estudos de Coortes , Estudos Prospectivos
2.
Inorg Chem ; 54(15): 7291-300, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26200797

RESUMO

Solvent-free spin crossover Fe(II) complex fac-[Fe(II)(HL(n-Pr))3]Cl·PF6 was prepared, where HL(n-Pr) denotes 2-methylimidazol-4-yl-methylideneamino-n-propyl. The magnetic susceptibility measurements at scan rate of 0.5 K min(-1) showed two successive spin transition processes consisting of the first spin transition T1 centered at 122 K (T1↑ = 127.1 K, T1↓ = 115.8 K) and the second spin transition T2 centered at ca. 105 K (T2↑ = 115.8 K, T2↓ = 97.2 K). The magnetic susceptibility measurements at the scan rate of 2.0, 1.0, 0.5, 0.25, and 0.1 K min(-1) showed two scan speed dependent spin transitions, while the Mössbauer spectra detected only the first spin transition T1. The crystal structures were determined at 160, 143, 120, 110, 95 K in the cooling mode, and 110, 120, and 130 K in the warming mode so as to follow the spin transition process of high-spin HS → HS(T1) → HS(T2) → low-spin LS → LS(T2) → LS(T1) → HS. The crystal structures at all temperatures have a triclinic space group P1̅ with Z = 2. The complex-cation has an octahedral N6 coordination geometry with three bidentate ligands and assume a facial-isomer with Δ- and Λ-enantimorphs. Three imidazole groups of fac-[Fe(II)(HL(n-Pr))3](2+) are hydrogen-bonded to three Cl(-) ions. The 3:3 NH(imidazole)···Cl(-) hydrogen-bonds form a stepwise ladder assembly structure, which is maintained during the spin transition process. The spin transition process is related to the structural changes of the FeN6 coordination environment, the order-disorder of PF6(-) anion, and the conformation change of n-propyl groups. The Fe-N bond distance in the HS state is longer by 0.2 Å than that in the LS state. Disorder of PF6(-) anion is not observed in the LS state but in the HS state. The conformational changes of n-propyl groups are found in the spin transition processes except for HS → HS(T1) → HS(T2).

3.
Inorg Chem ; 52(10): 6160-78, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23646986

RESUMO

A series of 3d-4f binuclear complexes, [M(3-MeOsaltn)(MeOH)x(ac)Ln(hfac)2] (x = 0 for M = Cu(II), Zn(II); x = 1 for M = Co(II), Ni(II); Ln = Gd(III), Tb(III), Dy(III), La(III)), have been synthesized and characterized, where 3-MeOsaltn, ac, and hfac denote N,N'-bis(3-methoxy-2-oxybenzylidene)-1,3-propanediaminato, acetato, and hexafluoroacetylacetonato, respectively. The X-ray analyses demonstrated that all the complexes have an acetato- and diphenolato-bridged M(II)-Ln(III) binuclear structure. The Cu(II)-Ln(III) and Zn(II)-Ln(III) complexes are crystallized in an isomorphous triclinic space group P1, where the Cu(II) or Zn(II) ion has square pyramidal coordination geometry with N2O2 donor atoms of 3-MeOsaltn at the equatorial coordination sites and one oxygen atom of the bridging acetato ion at the axial site. The Co(II)-Ln(III) and Ni(II)-Ln(III) complexes are crystallized in an isomorphous monoclinic space group P2(1)/c, where the Co(II) or Ni(II) ion at the high-spin state has an octahedral coordination environment with N2O2 donor atoms of 3-MeOsaltn at the equatorial sites, and one oxygen atom of the bridged acetato and a methanol oxygen atom at the two axial sites. Each Ln(III) ion for all the complexes is coordinated by four oxygen atoms of two phenolato and two methoxy oxygen atoms of "ligand-complex" M(3-MeOsaltn), four oxygen atoms of two hfac(-), and one oxygen atom of the bridging acetato ion; thus, the coordination number is nine. The temperature dependent magnetic susceptibilities from 1.9 to 300 K and the field-dependent magnetization up to 5 T at 1.9 K were measured. Due to the important orbital contributions of the Ln(III) (Tb(III), Dy(III)) and to a lesser extent the M(II) (Ni(II), Co(II)) components, the magnetic interaction between M(II) and Ln(III) ions were investigated by an empirical approach based on a comparison of the magnetic properties of the M(II)-Ln(III), Zn(II)-Ln(III), and M(II)-La(III) complexes. The differences of χ(M)T and M(H) values for the M(II)-Ln(III), Zn(II)-Ln(III) and those for the M(II)-La(III) complexes, that is, Δ(T) = (χ(M)T)(MLn) - (χ(M)T)(ZnLn) - (χ(M)T)(MLa) = J(MLn)(T) and Δ(H) = M(MLn)(H) - M(ZnLn)(H) - M(MLa)(H) = J(MLn)(H), give the information of 3d-4f magnetic interaction. The magnetic interactions are ferromagnetic if M(II) = (Cu(II), Ni(II), and Co(II)) and Ln = (Gd(III), Tb(III), and Dy(III)). The magnitudes of the ferromagnetic interaction, J(MLn)(T) and J(MLn)(H), are in the order Cu(II)-Gd(III) > Cu(II)-Dy(III) > Cu(II)-Tb(III), while those are in the order of M(II)-Gd(III) ≈ M(II)-Tb(III) > M(II)-Dy(III) for M(II) = Ni(II) and Co(II). Alternating current (ac) susceptibility measurements demonstrated that the Ni(II)-Tb(III) and Co(II)-Tb(III) complexes showed out-of-phase signal with frequency-dependence and the Ni(II)-Dy(III) and Co(II)-Dy(III) complexes showed small frequency-dependence. The energy barrier for the spin flipping was estimated from the Arrhenius plot to be 14.9(6) and 17.0(4) K for the Ni(II)-Tb(III) and Co(II)-Tb(III) complexes, respectively, under a dc bias field of 1000 Oe.


Assuntos
Acetatos/química , Complexos de Coordenação/química , Elementos da Série dos Lantanídeos/química , Metais Pesados/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Fenóis/química , Cristalografia por Raios X , Campos Magnéticos , Modelos Moleculares , Estrutura Molecular
4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): m307, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412449

RESUMO

In the title compound, [Ni(3)(C(10)H(22)N(2)S(2))(2)](ClO(4))(2), the complex cation consists of a nickel(II) ion and two [Ni(C(10)H(22)N(2)S(2))] units with an N(2)S(2) tetra-dentate ligand, 3,3'-[1,2-ethane-diylbis(methyl-imino)]bis-(1-propane-thiol-ate). The central Ni(II) ion is located on a crystallographic inversion centre and is bound to the four S atoms of the two [Ni(C(10)H(22)N(2)S(2))] units to form a linear sulfur-bridged trimetallic moiety. The dihedral angle between the central NiS(4) plane and the terminal NiN(2)S(2) plane is 145.71 (5)°. In the [Ni(C(10)H(22)N(2)S(2))] unit, the two methyl groups on the chelating N atoms are cis to each other, and the two six-membered N,S-chelate rings adopt a chair conformation. The Ni-S bond lengths and the S-Ni-S bite angles in the central NiS(4) group are similar to those in the [Ni(C(10)H(22)N(2)S(2))] unit.

5.
Inorg Chem ; 50(22): 11303-5, 2011 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-22026550

RESUMO

A series of spin-crossover (SCO) iron(II) compounds, fac-[Fe(II)(HL(R))(3)]Cl·PF(6) [R = methyl (Me, 1), ethyl (Et, 2), n-propyl (n-Pr, 3), n-butyl (n-Bu, 4), and n-pentyl (n-Pen, 5)], were synthesized, where HL(R) denotes a series of [(2-methylimidazol-4-yl)methylidene]monoalkylamines. The cations fac-[Fe(II)(HL(R))(3)](2+) and chloride anions associate through 3:3 imidazole···chloride hydrogen bonding. This hydrogen-bonding motif gives rise to a variety of assembly structures consisting of a one-dimensional ladder for 3 and 4, two kinds of two-dimensional networks for 1 and 2, and a cubane-like structure for 5. The compounds exhibit various types of SCO transitions between high-spin (S = 2) and low-spin (S = 0) states as a result of their intermolecular interactions.

6.
Inorg Chem ; 50(9): 3981-7, 2011 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-21446690

RESUMO

The tetrafluoroborate salt of bis{8-(diphenylphosphino)quinoline}copper(I), [Cu(Ph(2)Pqn)(2)]BF(4), afforded orange prismatic (2O) or yellow columnar (2Y) crystals, dependent on the solvent and concentration of the recrystallization solution used. X-ray analysis revealed that crystals of 2O and 2Y had the same composition and exhibited different crystal systems: 2O was triclinic, with space group P ̅1 and Z = 2, and 2Y was monoclinic with space group P2(1)/c and Z = 4. In these crystals, the tetrahedral copper(I) complex exhibited a strong "rocking distortion" toward a trigonal pyramidal coordination geometry (by a slide translation of one of the unsymmetrical bidentate chelating ligands along the tetrahedral edge). In addition, both the 2O and 2Y complexes showed a "flattening distortion", meaning that the dihedral angle between the two chelate planes were off-perpendicular and oriented toward opposite directions, which resulted in a pair of distortion isomers: syn clinal (sc: 2O) and anti clinal (ac: 2Y). (31)P CP-MAS NMR spectroscopy indicated that 2O and 2Y could be distinguished. Both isomers exhibited inequivalent P atoms, but a larger difference in chemical shift was observed in 2Y. TD-DFT calculations reproduced the difference in spectra between the orange- and yellow-colored complexes, which originated from metal-to-ligand charge-transfer transitions.

7.
Nagoya J Med Sci ; 83(2): 331-341, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34239181

RESUMO

Previous studies have focused on the association between poor oral health and upper aerodigestive tract (UADT) cancer. However, whether toothbrushing and tooth loss are associated with UADT cancer risk is still unclear. Therefore, we investigated the association between toothbrushing or tooth loss and UADT cancer in the Longitudinal Evaluation of Multi-phasic, Odontological, and Nutritional Associations in Dentists (LEMONADE) cohort study. From 2001 to 2006, we recruited 20,445 dentists (mean age ± standard deviation, 51.8 ± 12.0 years; 1,607 women [7.9%]) and followed for incidence or mortality of UADT cancer through March 2014. Information on lifestyle and oral health was collected by the baseline questionnaire. The Cox proportional hazards model was used to estimate hazard ratios (HRs) for UADT cancer and corresponding 95% confidence intervals (CI) for brushing frequency and tooth loss with adjustment for covariates. During the mean follow-up of 9.5 years, we confirmed 62 incident or fatal cases of UADT cancer. Infrequent toothbrushing (< 2 times/day) was significantly associated with increased risk of UADT cancer (multivariate HR = 2.13, 95% CI: 1.04-4.37). On the contrary, tooth loss was not significantly correlated with UADT cancer risk; multivariate HR was 1.03 (95% CI: 0.41-2.61) for loss of 15-27 teeth and 1.37 (0.50-3.75) for that of 28 teeth compared to tooth loss of 0-14 teeth. In conclusion, Infrequent toothbrushing was significantly associated with the risk of UADT cancer.


Assuntos
Neoplasias , Perda de Dente , Adulto , Estudos de Coortes , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Perda de Dente/epidemiologia , Escovação Dentária
8.
Clin Endocrinol (Oxf) ; 73(4): 484-90, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20550530

RESUMO

BACKGROUND: We recently identified a novel anorexigenic protein, nesfatin-1, which is processed from nesfatin/nucleobindin-2 (NUCB2). However, the clinical importance of this protein has not been determined. OBJECTIVE: To investigate its clinical significance in humans, we have established a new specific enzyme-linked immunosorbent assay (ELISA) for human nesfatin-1 in peripheral blood and measured its circulating concentration in healthy subjects. DESIGN: The new sandwich-type ELISA method was validated and then used to measure nesfatin-1 levels in plasma samples, under overnight fasting conditions, followed by oral glucose tolerance and meal tests. PATIENTS AND MEASUREMENTS: A total of 43 nonobese males (age: 24.5 ± 0.6, body mass index (BMI); 21.1 ± 0.3 kg/m(2)) were recruited to the study for evaluating fasting concentrations of nesfatin-1. In those, fifteen subjects underwent a 75- g oral glucose tolerance test (OGTT) and another 15 underwent a meal test. In addition, fasting concentrations of nesfatin-1 were measured in nine males with high BMI (age: 32.4 ± 3.7, BMI; 37.3 ± 3.8 kg/m(2)). RESULTS: Peripheral concentrations of nesfatin-1 showed a significant negative correlation with BMI, percentage body fat, body fat weight and blood glucose (P < 0.05). Nesfatin-1 concentrations were not significantly changed during OGTT and meal tests. Fasting nesfatin-1 levels were significantly lower in subjects with high BMI compared to nonobese subjects (P < 0.05). CONCLUSIONS: A new specific and sensitive ELISA for nesfatin-1 was established. Further accumulation of clinical observations is necessary to clarify the role of circulating nesfatin-1 in various metabolic disorders.


Assuntos
Índice de Massa Corporal , Jejum/sangue , Hormônios Peptídicos/sangue , Adulto , Glicemia/análise , Proteínas de Ligação ao Cálcio , Proteínas de Ligação a DNA , Ensaio de Imunoadsorção Enzimática , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Masculino , Proteínas do Tecido Nervoso , Nucleobindinas , Hormônios Peptídicos/fisiologia
9.
Chemistry ; 16(47): 14060-8, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21077055

RESUMO

A new spin-crossover (SC) complex [Fe(II)H(2)L(2-Me)][AsF(6)](2) has been synthesized, in which H(2)L(2-Me) denotes the chirogenic hexadentate N(6) Schiff-base ligand bis{[(2-methylimidazol-4-yl)methylidene]-3-aminopropyl}ethylenediamine. This complex has revealed a rich variety of phases during its two-step thermal crossover, as well as photoinduced spin-state switching. A high-symmetry high-spin (HS, S=2) phase, a low-symmetry low-spin (LS, S=0) phase, an intermediate phase characterized by an unprecedented lozenge pattern of 12 predominantly HS molecular crystallographic sites confining 18 predominantly LS molecular crystallographic sites, and a photoinduced low-symmetry HS phase have been accurately evidenced by temperature-dependent magnetic susceptibility, Mössbauer spectroscopy, and crystallographic studies. This variety of phases illustrates the multi-stability of this system, which results from coupling between the electronic states and structural instabilities.

10.
Inorg Chem ; 49(4): 1517-23, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20092285

RESUMO

2-Methylimidazol-4-yl-methylideneamino-2-ethylpyridine (abbreviated as HL(Me)) is the 1:1 condensation product of 2-methyl-4-formylimidazole and 2-aminoethylpyridine and functions as a bidentate ligand to the iron(II) ion to produce the 3:1 complexes together with anions, [Fe(HL(Me))(3)]X(2) (X = PF(6) (1), ClO(4) (2), BF(4) (3)). The magnetic susceptibilities, differential scanning calorimetric measurements, and Mossbauer spectral measurements demonstrated that complexes 1, 2, and 3 showed a steep one-step spin crossover (SCO) between the high-spin (HS, S = 2) and low-spin (LS, S = 0) states with small thermal hysteresis. Three complexes have an isomorphous structure and are crystallized in the same monoclinic space group, C2/c, both in the HS and LS states. The iron(II) ion has the octahedral coordination geometry of a facial isomer with N(6) donor atoms of three bidentate ligands, in which an imidazole and an imine nitrogen atom per ligand participate in the formation of the coordination bond, but the pyridine nitrogen is free from coordination. The complex cation fac-[Fe(HL(Me))(3)](2+) is a chiral species with a Delta or Lambda isomer, and the adjacent Delta and Lambda isomers are linked alternately by an intermolecular imidazole-pyridine NH...N hydrogen bond to produce an achiral 1D chain. The two remaining imidazole moieties per complex are hydrogen-bonded to the anions that occupy the space among the chains. The SCO profile becomes steeper with the decrease of the anion size (73.0 A(3) for PF(6)(-), 54.4 A(3) for ClO(4)(-), and 53.4 A(3) for BF(4)(-)). The SCO transition temperature T(1/2) of the PF(6) (1), ClO(4) (2), and BF(4) (3) salts estimated from the magnetic susceptibility measurements are (T( downward arrow) = 151.8 K, T( upward arrow) = 155.3 K), (T( downward arrow) = 184.5 K, T( upward arrow) = 186.0 K), and (T( downward arrow) = 146.4 K, T( upward arrow) = 148.2 K), respectively, indicating that the T(1/2) value is not in accord with the anion size.

11.
Inorg Chem ; 49(20): 9125-35, 2010 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-20446714

RESUMO

Trinuclear linear 3d-4f-3d complexes (3d = Mn(II), Fe(II), Co(II), Zn(II) and 4f = La(III), Gd(III), Tb(III), Dy(III)) were prepared by using a tripodal nonadentate Schiff base ligand, N,N',N''-tris(2-hydroxy-3-methoxybenzilidene)-2-(aminomethyl)-2-methyl-1,3-propanediamine. The structural determinations showed that in these complexes two distorted trigonal prismatic transition metal complexes of identical chirality are assembled through 4f cations. The Mn and Fe entities crystallize in the chiral space group P2(1)2(1)2(1) as pure enantiomers; the cobalt complexes exhibit a less straightforward behavior. All Mn, Fe, and Co complexes experience M(II)-Ln(III) ferromagnetic interactions. The Mn-Gd interaction is weak (0.08 cm(-1)) in comparison to the Fe-Gd (0.69 cm(-1)) and Co-Gd (0.52 cm(-1)) ones while the single ion zero field splitting (ZFS) term D is larger for the Fe complexes (5.7 cm(-1)) than for the cobalt ones. The cobalt complexes behave as single-molecules magnets (SMMs) with large magnetization hysteresis loops, as a consequence of the particularly slow magnetic relaxation characterizing these trinuclear molecules. Such large hysteresis loops, which are observed for the first time in Co-Ln complexes, confirm that quantum tunnelling of the magnetization does not operate in the Co-Gd-Co complex.

12.
Inorg Chem ; 48(15): 7211-29, 2009 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-19722691

RESUMO

A tridentate ligand ((2-methylimidazol-4-yl)methylidene)histamine (abbreviated as H(2)L(2-Me)), that is, the 1:1 condensation product of 2-methyl-4-formylimidazole and histamine, was used for the syntheses of a new family of iron(II) spin-crossover (SCO) complexes with the general chemical formulas [Fe(H(2)L(2-Me))(2)]X(2) x solvent (X = Cl, ClO(4), and BPh(4); solvent = 2-PrOH and CH(3)CN) and [Fe(H(2)L(2-Me))(2)]X x Y x solvent (X = Cl and Br; Y = ClO(4), BF(4), PF(6), and AsF(6); solvent = EtOH and 2-PrOH). The complex cation [Fe(H(2)L(2-Me))(2)](2+) is a chiral species due to an octahedral coordination of two unsymmetrical tridentate ligands, has a ligand field strength around the spin-crossover point, and is hydrogen-bonded to anions to form a variety of network structures. The dichloride complexes [Fe(H(2)L(2-Me))(2)]Cl(2) x 2-PrOH x 0.5 H(2)O (1) and [Fe(H(2)L(2-Me))(2)]Cl(2) x 2-PrOH x H(2)O (1') have a one-dimensional (1D) structure, in which adjacent two chiral complex-cations are doubly bridged by two Cl(-) ions through NH(histamine)...Cl(-)...HN(2-methyl-4-formylimidazole) hydrogen bonds to give a chiral 1D rod. The chiral rods with the same chirality are stacked in the crystal lattices to give a conglomerate, 1, and those with the opposite chiralities are stacked to give a racemic compound, 1'. The enantiomeric circular dichromism spectra of 1 gave definitive evidence of the conglomerate. Compound 1 showed a two-step SCO, while the desolvated sample showed a steep one-step SCO at T(1/2) = 180 K. A series of complexes, [Fe(H(2)L(2-Me))(2)]Cl x X x EtOH (X = ClO(4) (2a), BF(4) (2b), PF(6) (2c), and AsF(6) (2d)), [Fe(H(2)L(2-Me))(2)]Cl x ClO(4) x 0.5(1-PrOH) x 1.5 H(2)O (2a'), and [Fe(H(2)L(2-Me))(2)]Br x ClO(4) x 0.5 EtOH (2a''), display an isomorphous two-dimensional (2D) network at room temperature (296 K), in which the structure is constructed by the NH...Cl(-) (or Br(-)) hydrogen bonds between the imidazole NH groups of [Fe(H(2)L(2-Me))(2)](2+) and the Cl(-) (or Br(-)) ion as a connector. The complexes showed a variety of SCO properties depending on the anion, solvent molecule, and the kind of bridging halogen ion. The complexes of ClO(4)(-) (2a, 2a', 2a'') and BF(4)(-) (2b) with smaller anions showed a two-step SCO with a wide temperature region of the intermediate state of (high-spin (HS) + low-spin (LS))/2 state, their values of (T(1/2,1), T(1/2,2)) being (75, 255 K), (100, 220 K), (110, 220 K), and (100, 260 K), respectively, where the crystal changes from monoclinic P2(1)/n in the HS state to triclinic P1 in the intermediate state. The complexes of PF(6)(-) (2c) and AsF(6)(-) (2d) with larger anions showed a one-step SCO at T(1/2) = 198 and 173 K, respectively, in which the crystal system and space group showed no change during the spin transition. The crystal solvent and halide ion also affected the completeness of the SCO in the lower-temperature region and the steepness of the SCO profile. The experimental results were correlated to the theoretical results based on an Ising-like model. [Fe(H(2)L(2-Me))(2)](BPh(4))(2) x CH(3)CN (3) has no network structure. [Fe(H(2)L(2-Me))(2)](ClO(4))(2) (4) assumes a chiral 3D network structure constructed by the hydrogen bonds between the imidazole groups of one enantiomorph [Fe(H(2)L(2-Me))(2)](2+) and the bridging ClO(4)(-) ion. Compounds 3 and 4 in the solid states are in the HS state, demonstrating that the formation of imidazole-Cl(-) or Br-hydrogen bonds can give SCO properties, but the hydrogen bond of imidazole-ClO(4)(-) cannot give SCO.

13.
Inorg Chem ; 48(12): 5555-61, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19397285

RESUMO

The syntheses, structural determinations, and magnetic studies of two trinuclear Ni-Gd-Ni complexes are described. The structural studies demonstrate that the two complexes present a linear arrangement of the Ni and Gd ions, with Ni ions in slightly distorted square-pyramidal or octahedral environments in complexes 1 and 2, respectively. The Ni and Gd ions are linked by two or three phenoxo bridges, so that complexes 1 and 2 present edge-sharing or face-sharing bridging cores. Ferromagnetic interactions operate in these complexes. While a unique J parameter is able to fit the magnetic data of complex 2, two very different J constants are needed for 1. This result is at first sight surprising, for the structural data of the two Ni-O(2)-Gd cores in complex 1 are quite similar (similar Ni-O and Gd-O bond lengths, similar angles, and dihedral angles), the only difference coming from the angle between the planes defined by the Gd ion and the two bridging phenoxo oxygen atoms of each Ni-O(2)-Gd half core. This latter magnetic behavior can be considered as a signature for the participation of 5d Gd(III) orbitals in the exchange interaction mechanism and can explain why edge-sharing complexes have larger J parameters than face-sharing complexes.

14.
Inorg Chem ; 48(18): 8784-95, 2009 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-19694455

RESUMO

Mononuclear [Fe(H(2)L(R))(2)](2+) and dinuclear [Fe(2)(H(2)L(R))(3)](4+) (R = H, 2-Me, 5-Me) complexes containing the new imidazole-4-carbaldehyde azine ligand (H(2)L(H)) and its derivatives (H(2)L(2-Me) and H(2)L(5-Me)) prepared from the condensation reaction of 4-formylimidazole or 2-methyl- or 5-methyl-4-formylimidazole with hydrazine (2:1) were prepared, and their magnetostructural relationships were studied. In the mononuclear complexes, H(2)L(R) acts as an unsymmetrical tridentate ligand with two imidazole nitrogen atoms and one azine nitrogen atom, while in the dinuclear complexes, H(2)L(R) acts as a dinucleating ligand employing four nitrogen atoms to form a triple helicate. At room temperature, [Fe(2)(H(2)L(H))(3)](ClO(4))(4) and [Fe(2)(H(2)L(2-Me))(3)](ClO(4))(4) were in the high-spin (HS) and low-spin (LS) states, respectively. The results are in accordance with the ligand field strength of H(2)L(2-Me) with electron-donating methyl groups being stronger than H(2)L(H), with the order of the ligand field strengths being H(2)L(2-Me) > H(2)L(H). However, in the mononuclear [Fe(H(2)L(H))(2)](ClO(4))(2) and [Fe(H(2)L(2-Me))(2)](ClO(4))(2) complexes, a different order of ligand field strengths, H(2)L(H) > H(2)L(2-Me), was observed because [Fe(H(2)L(H))(2)](ClO(4))(2) was in the LS state while [Fe(H(2)L(2-Me))(2)](ClO(4))(2) was in the HS state at room temperature. X-ray structural studies revealed that the interligand steric repulsion between a methyl group of an H(2)L(2-Me) ligand and the other ligand in [Fe(H(2)L(2-Me))(2)](ClO(4))(2) is responsible for the observed change in the spin state. Two kinds of crystals, needles and blocks, were isolated for [Fe(2)(H(2)L(H))(3)](BF(4))(4), and both exhibited a sharp spin transition, [LS-HS] <--> [HS-HS]. The spin transition of the block crystals is more abrupt with a hysteresis, T(c) upward arrow = 190 K and T(c) downward arrow = 183 K with DeltaT = 7 K.

15.
Inorg Chem ; 47(13): 5736-45, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18512903

RESUMO

Heterodinuclear [(Ni (II)L)Ln (III)(hfac) 2(EtOH)] (H 3L = 1,1,1-tris[(salicylideneamino)methyl]ethane; Ln = Eu, Gd, Tb, and Dy; hfac = hexafluoroacetylacetonate) complexes ( 1.Ln) were prepared by treating [Ni(H 1.5L)]Cl 0.5 ( 1) with [Ln(hfac) 3(H 2O) 2] and triethylamine in ethanol (1:1:1). All 1.Ln complexes ( 1.Eu, 1.Gd, 1.Tb, and 1.Dy) crystallized in the triclinic space group P1 (No. 2) with Z = 2 with very similar structures. Each complex is a face-sharing dinuclear molecule. The Ni (II) ion is coordinated by the L (3-) ligand in a N 3O 3 coordination sphere, and the three phenolate oxygen atoms coordinate to an Ln (III) ion as bridging atoms. The Ln (III) ion is eight-coordinate, with four oxygen atoms of two hfac (-)'s, three phenolate oxygen atoms of L (3-), and one ethanol oxygen atom coordinated. Temperature-dependent magnetic susceptibility and field-dependent magnetization measurements showed a ferromagnetic interaction between Ni (II) and Gd (III) in 1.Gd. The Ni (II)-Ln (III) magnetic interactions in 1.Eu, 1.Tb, and 1.Dy were evaluated by comparing their magnetic susceptibilities with those of the isostructural Zn (II)-Ln (III) complexes, [(ZnL)Ln(hfac) 2(EtOH)] ( 2.Ln) containing a diamagnetic Zn (II) ion. A ferromagnetic interaction was indicated in 1.Tb and 1.Dy, while the interaction between Ni (II) and Eu (III) was negligible in 1.Eu. The magnetic behaviors of 1.Dy and 2.Dy were analyzed theoretically to give insight into the sublevel structures of the Dy (III) ion and its coupling with Ni (II). Frequency dependence in the ac susceptibility signals was observed in 1.Dy.


Assuntos
Elementos da Série dos Lantanídeos/química , Níquel/química , Compostos Organometálicos/síntese química , Magnetismo , Compostos Organometálicos/química
16.
Exp Anim ; 57(5): 485-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18946186

RESUMO

In this study, in order to clarify the kinetics of leptin, we focused on the ratio of leptin concentrations in cerebrospinal fluid and serum in aged male rats, and examined the weight of epididymal fat, and the passage rate of leptin through the blood-brain barrier. In the lighter animals, the epididymal fat weight was low, while leptin concentrations in the serum and cerebrospinal fluid were also low. Conversely, in the heavier animals, the weight of epididymal fat and leptin concentrations in the serum and cerebrospinal fluid were higher. With regard to the ratio of leptin in the cerebrospinal fluid and serum, the passage rate of leptin through the blood-brain barrier was lower in the heavier animals than in the lighter animals.


Assuntos
Tecido Adiposo/anatomia & histologia , Barreira Hematoencefálica/fisiologia , Epididimo/anatomia & histologia , Leptina/metabolismo , Envelhecimento , Animais , Peso Corporal , Leptina/sangue , Leptina/líquido cefalorraquidiano , Masculino , Ratos
17.
PLoS One ; 13(4): e0195813, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29652898

RESUMO

Although associations between oral health and pneumonia have been reported in previous studies, particularly in the institutionalized elderly, few prospective studies have investigated the association between oral condition and pneumonia among community-dwelling people and whether the findings among inpatients or patients in nursing homes are applicable to the general population is still unclear. The oral bacteria propagated in the periodontal regions may drop into the lung and increase the risk of pneumonia. We, therefore, investigated the association of tooth loss with mortality from pneumonia in a cohort study of Japanese dentists. Members of the Japan Dental Association (JDA) participated in the LEMONADE (Longitudinal Evaluation of Multi-phasic, Odontological and Nutritional Associations in Dentists) Study. From 2001 to 2006, they completed a baseline questionnaire on lifestyle and health factors including the number of teeth lost (excluding third molars). We followed 19,775 participants (mean age ± standard deviation, 51.4 ± 11.7 years; 1,573 women [8.0%] and 18,202 men [92.0%]) for mortality from pneumonia (ICD-10, J12-J18). Mortality data were collected via the fraternal insurance program of the JDA. The hazard ratios (HRs) were estimated with adjustment for sex, age, body mass index, smoking status, physical activity and diabetes history. During the median follow-up period of 9.5 years, we documented 68 deaths from pneumonia. Participants who were edentulous at baseline were at significantly increased risk of mortality from pneumonia. The multivariable-adjusted HRs were 2.07 (95% confidence interval [CI], 1.09-3.95) for the edentulous and 1.60 (95% CI, 0.83-3.10) for loss of 15-27 teeth relative to loss of 0-14 teeth (trend p = 0.026). The HR per one tooth loss was also significant; 1.031 (95% CI, 1.004-1.060). In conclusion, a large number of teeth lost may indicate an increased risk of mortality from pneumonia in community-dwelling populations.


Assuntos
Pneumonia/mortalidade , Perda de Dente/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comorbidade , Odontólogos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/epidemiologia , Modelos de Riscos Proporcionais , Vigilância em Saúde Pública , Fatores de Risco
18.
Chem Commun (Camb) ; (18): 1950-2, 2006 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-16767246

RESUMO

Two heterotrinuclear complexes, [Mn(II)(Ni(II)L)2].2CH3OH (where H3L = 1,1,1-tris(N-salicylideneaminomethyl)ethane) and [Fe(III)(Ni(II)L)2]NO3.C2H5OH, consisting of three face-sharing octahedra have been prepared; although these complexes have closely related structures and have the same 1-5/2-1 spin system, they show completely different magnetic interactions between the adjacent metal ions: ferromagnetic (Ni(II)-Mn(II)) and antiferromagnetic (Ni(II)-Fe(III)).

19.
Clin Chim Acta ; 351(1-2): 115-20, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15563879

RESUMO

BACKGROUND: Apolipoprotein B-48 (apoB-48) is produced by the small intestine, as a part of chylomicrons (CMs), and appears to be a suitable marker for clinical studies of postprandial lipoproteins and related cardiovascular risk factors. We have developed an assay for routine analysis to quantify apoB-48 in serum or plasma. METHODS: A microtiter plate was coated with monoclonal antibody (4C8) raised against apoB-48 C-terminal specific decapeptide. Serum samples were diluted 100-fold with 0.05 mol/l Tris-HCl buffer (with or without 0.1% Triton X-100). Appropriate calibration curves were obtained in the ELISA by using apoB-48 recombinant antigen. RESULTS: No cross-reactivity (<0.001%) was found with apoB-100, as verified by ELISA and Western blot analyses. Intra- and inter-assay CVs were 4.8% and 5.4%, respectively. Recovery of added recombinant apoB-48 in serum was within 94-105%. The assay linearity was intact >5-fold dilution of serum by dilution buffer. ApoB-48 levels in healthy controls (n=18) at fasting were within the range of 2.69-6.56 microg/ml (mean+/-S.D.: 4.60+/-1.54 microg/ml). In healthy subjects, serum apoB-48 concentrations markedly increased in the postprandial state, in parallel with serum triglycerides. CONCLUSION: This method for measuring apoB-48 using the monoclonal antibody 4C8 is simple, reliable and suitable for routine analyses.


Assuntos
Apolipoproteínas B/sangue , Adulto , Animais , Anticorpos Monoclonais , Apolipoproteína B-48 , Western Blotting , Calibragem , Quilomícrons/metabolismo , Reações Cruzadas , Detergentes , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/sangue , Valores de Referência
20.
Dalton Trans ; 44(36): 15757-60, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26270329

RESUMO

A reaction of [PdCl2(cod)] (cod = 1,5-cyclooctadiene) and an E/Z mixture of quinoline-2-carbaldehyde (pyridine-2-carbonyl)hydrazone (HL) gave two kinds of Pd(II) mononuclear complexes, [PdCl(Z-L-κ(3)N,N',N'')] (1) and [PdCl2(E-HL'-κ(2)N,N')] (2), where L(-) is the deprotonated hydrazonate anion and HL' is the quinolinium-hydrazonate zwitterionic form of HL. Complex 2 is gradually converted to 1 in solution, and complex 1 is a good precursor to prepare a Pd(II)/Ru(II) heterodinuclear complex bridged by hydrazonate, trans(Cl,Cl)-[RuCl2(PPh3)2(µ-L)PdCl] (3).

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