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1.
Artigo em Inglês | MEDLINE | ID: mdl-32662185

RESUMO

Metal node design is crucial for obtaining structurally diverse coordination polymers (CPs) and metal-organic frameworks with desirable properties; however, Fe(II) ions are exclusively six-coordinated. Herein, we present a cyanide-bridged three-dimensional (3D) CP, FePd(CN)4, bearing four-coordinate Fe(II) ions, which is synthesized by thermal treatment of a two-dimensional (2D) six-coordinate Fe(II) CP, Fe(H2O)2Pd(CN)4·4H2O, to remove water molecules. Atomic-resolution transmission electron microscopy and powder X-ray and neutron diffraction measurements revealed that the FePd(CN)4 structure is composed of a two-fold interpenetrated PtS topology network, where the Fe(II) center demonstrates an intermediate geometry between tetrahedral and square-planar coordination. This four-coordinate Fe(II) center with the distorted geometry can act as a thermo-responsive "flexible" node in the PtS network.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32608036

RESUMO

Cell membranes contain lateral systems that consist of various lipid compositions and actin cytoskeleton, providing two-dimensional (2D) platforms for chemical reactions. However, such complex 2D environments have not yet been used as a synthetic platform for artificial 2D nanomaterials. Herein, we demonstrate the direct synthesis of 2D coordination polymers (CPs) at the liquid-cell interface of the plasma membrane of living cells. The coordination-driven self-assembly of networking metal complex lipids produces cyanide-bridged CP layers with metal ions, enabling 'pseudo-membrane jackets' that produce long-lived micro-domains with a size of 1-5 µm. The resultant artificial and visible phase separation systems remain stable even in the absence of actin skeletons in cells. Moreover, the jackets achieved the enhancement of cellular calcium response to ATP. This confirms that the artificial nanomaterials formed via moderate coordinative intermolecular interactions create a 2D scaffold on complex cell membrane environments, thereby providing a unique tool for the chemical control of cell functions.

3.
Chem Commun (Camb) ; 56(57): 7957-7960, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32537623

RESUMO

Recently, non-crystalline coordination materials have been shown to represent a versatile class of functional materials. However, such materials incorporating metal complex clusters have remained largely unexplored. Herein, we demonstrate that a luminescent tetranuclear ReV cluster melts at 489 K, with the cluster structure being maintained in the corresponding supercooled ionic liquid phase.

4.
Chem Commun (Camb) ; 56(43): 5835-5838, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32329501

RESUMO

A hexagonal cobalt(ii) metallacycle and its "lipid packaged" derivatives, [Co6(R-bisterpy)6]X12 (R = H, OC16H33, OC27H55; X = BF4, C12-Glu), have been synthesized and characterized. The compounds incorporating BF4- anions formed sphere-like aggregates while the compounds with C12-Glu lipid anions gave double-layered honeycomb architectures composed of hexagonal stacked tubular structures, which exhibit spin crossover behaviour.

7.
Inorg Chem ; 58(19): 12739-12747, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31539234

RESUMO

Two-dimensional Hofmann-type coordination polymers of type Mn(H2O)2[Pd(CN)4]·xH2O (1·xH2O; x = 0, 1, and 4), Mn(H2O)(MeOH)[Pd(CN)4]·2MeOH (2·2MeOH), and Mn(MeOH)2[Pd(CN)4]·MeOH (3·MeOH) have been synthesized. The homosolvent-bound 1·4H2O, 1·H2O, and 3·MeOH polymers consist of undulating layer structures, whereas the structure of heterosolvent-bound 2·2MeOH consists of "Janus-like" flat layers in which water-bound and MeOH-bound-sides are present. 1·4H2O and 1·H2O exhibited anisotropic two-dimensional thermal expansions involving structural transformations of the undulating layers; one layer axis expands while the other contracts. 2·2MeOH exhibits anisotropic thermal expansion in which the flat layers shift sideways as the temperature is increased, with colossal interlayer expansion occurring (αc = +200 MK-1 over 140-180 K, αc = +165 MK-1 over 200-280 K). 3·MeOH also showed colossal interlayer expansion (αc = +216 MK-1) together with expansion of the undulating layers.

8.
J Clin Neurosci ; 66: 271-272, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178306

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) has a wide disease spectrum and sometimes shows abnormal eye movement with brainstem manifestations. However, bilateral oculomotor nerve palsy with a midbrain lesion has never been reported in a patient with NMOSD. We describe a 61-year-old woman with progressive ptosis and diplopia. She displayed bilateral oculomotor nerve palsy and hypersomnia. Brain MRI demonstrated abnormal signal intensities in the midbrain and around the third ventricle and hypothalamus with a mild contrast enhancement. A cerebrospinal fluid study indicated elevated protein and pleocytosis. Because serum anti-aquaporin-4 IgG antibody was positive, the patient was diagnosed with neuromyelitis optica spectrum disorder with aquaporin-4 IgG. We report for the first time bilateral oculomotor nerve palsy as an initial manifestation in a patient with aquaporin-4 positive NMOSD.


Assuntos
Aquaporina 4/sangue , Autoanticorpos/sangue , Neuromielite Óptica/sangue , Neuromielite Óptica/diagnóstico por imagem , Doenças do Nervo Oculomotor/sangue , Doenças do Nervo Oculomotor/diagnóstico por imagem , Tronco Encefálico/diagnóstico por imagem , Feminino , Humanos , Mesencéfalo/diagnóstico por imagem , Pessoa de Meia-Idade , Neuromielite Óptica/complicações , Doenças do Nervo Oculomotor/complicações
9.
Inorg Chem ; 58(11): 7409-7415, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31117627

RESUMO

The behavior of single-ion magnets (SIMs) that reflects large distortions of their coordination environments caused by the packing of long alkyl chains for two Co(II) complexes of the type [Co(C n-terpy)2](BF4)2 (C n-terpy = 4'-alkoxy-2,2':6',2″-terpyridine; n = 10 (1), 16 (2)) is reported. 1·2MeOH, which features a highly distorted octahedral high-spin Co(II) center, exhibits field-induced slow magnetic relaxation under an applied dc field of 1000 Oe. Further detailed analysis of the relaxation process indicated the prevalence of the Raman process at low temperature. Surprisingly, 2 shows a reverse spin transition (rST) and also exhibits remarkable field-induced SIM behavior, revealing the presence of magnetic anisotropy for this high-spin Co(II) species that is triggered by a structural phase transition. We present here the first examples of the coexistence of field-induced slow magnetic relaxation and rST associated with structural phase transitions involving long-alkyl-chain conformational changes from gauche to anti. These results indicate the prospect of inducing SIM properties in other distorted high-spin Co(II) species bearing long alkyl chains.

10.
J Stroke Cerebrovasc Dis ; 28(7): 1979-1986, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30982718

RESUMO

BACKGROUND: Hemorrhagic infarction (HI) is among the most severe complications that can occur following the administration of intravenous recombinant tissue plasminogen activator (rt-PA). In the present study, we aimed to determine the optimal cut-off points of blood pressure (BP) for HI after rt-PA treatment, and to compare our findings with those for other prediction models. METHODS: We analyzed data from 109 consecutive patients with stroke treated at our hospital between 2009 and 2016. HI was confirmed via computed tomography or magnetic resonance imaging. Patients were classified into a symptomatic HI group, an asymptomatic HI group, and a non-HI group. BP was measured on admission and before rt-PA treatment. Glucose Race Age Sex Pressure Stroke Severity (GRASPS) and Totaled Health Risks in Vascular Events (THRIVE) scores were also calculated. Receiver operating characteristic (ROC) analysis was used to determine factors associated with symptomatic and asymptomatic HI. RESULTS: Among the 109 total patients, 25 patients developed symptomatic HI, while 22 patients developed asymptomatic HI. ROC analysis for predicting symptomatic and asymptomatic HI revealed that the area under the curve for pretreatment systolic BP (SBP) was .88 (95% confidence interval[CI]: .83-.94), while those for GRASPS and THRIVE scores were .75 (95% CI: .66-.85) and .69 (95% CI: .59-.79), respectively. We identified an optimal cut-off point of 160 mm Hg (sensitivity: 82.3%; specificity: 76.6%; diagnostic accuracy: 80.0%; positive predictive value: 76.6%; negative predictive value: 82.5%). CONCLUSIONS: Pre-treatment SBP may be a simple predictor of symptomatic and asymptomatic HI in patients with stroke undergoing rt-PA treatment.


Assuntos
Pressão Sanguínea , Fibrinolíticos/efeitos adversos , Hemorragias Intracranianas/induzido quimicamente , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Infusões Intravenosas , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/fisiopatologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/efeitos adversos , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Ativador de Plasminogênio Tecidual/administração & dosagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Dalton Trans ; 48(24): 8617-8622, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-30942224

RESUMO

A homochiral one-dimensional (1D) Mn(iii) coordination polymer [MnL]n (1) was synthesised employing the N3O-donor tetradentate ligand (L = 2-hydroxy-N-[2-[[(2-aminophenyl)methylene]amino]-2-methylpropyl]-benzamide). The X-ray structure of 1 and its magnetic properties were investigated in detail. The crystal structure of 1 shows a homochiral helical arrangement in which spontaneous resolution has occurred, despite the ligand being achiral. Magnetic characterization revealed an antiferromagnetic interaction between manganese(iii) ions (J = -2.48 cm-1, g = 1.96) that leads to an antiferromagnetic spin-ordering phase transition at TN≈ 7 K. Noteworthily, 1 exhibits weak ferromagnetism with a relatively large coercive field of 3.0 kOe based on the spin canting, indicating the formation of a homochiral weak ferromagnet.

12.
Rinsho Shinkeigaku ; 59(4): 195-199, 2019 Apr 25.
Artigo em Japonês | MEDLINE | ID: mdl-30930366

RESUMO

A 73-year-old women visited emergency department because of sudden right hemiplegia. She had a history of duodenum papilla cancer terminal stage and multiple liver metastasis. On admission, diffusion weighted images revealed high intensity area at left middle cerebral artery territory. In addition, 3D-TOF MRA depicted proximal part of the left internal carotid artery. We performed endovascular thrombectomy because low platelet count met contraindication of intravenous recombinant tissue plasminogen activator therapy. Although we could get partial recanalization of middle cerebral artery occlusion after thrombectomy, the patient eventually died due to multiple organ failure. Autopsy findings showed white thrombus on mitral valve and also left middle cerebral artery occluded by similar white thrombus without infective findings. The patient was finally diagnosed with nonbacterial thrombotic endocarditis due to white thrombus on the mitral valve. We should select appropriate mechanical thrombectomy devices with a case of cerebral infarction due to nonbacterial thrombotic endocarditis because its thrombus is often white thrombus and would be hard.


Assuntos
Autopsia , Endocardite não Infecciosa/complicações , Endocardite não Infecciosa/patologia , Procedimentos Endovasculares , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Trombectomia/métodos , Idoso , Plaquetas/patologia , Endocardite não Infecciosa/cirurgia , Evolução Fatal , Feminino , Humanos , Imagem por Ressonância Magnética , Valva Mitral/patologia , Insuficiência de Múltiplos Órgãos/etiologia , Infarto do Miocárdio/cirurgia , Neuroimagem , Trombectomia/instrumentação
13.
Chemistry ; 25(31): 7521-7525, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-30964217

RESUMO

Control of ion arrangements in ionic liquids represents a major challenge owing to the presence of the predominant coulombic interactions between cationic and anionic ion species that forms the coulombic ordering. Here, water-induced ion rearrangement in a room-temperature ionic liquid (RT-IL) metal complex, (1-ethyl-3-methylimidazolium)2 [MnN(CN)4 ], is demonstrated through coordinative interactions between anions. Solidification occurred, which was associated with the formation of a "separated" structure consisting of cation columns and anionic cyanide-bridged one-dimensional coordination polymers. The energy diagram is in accord with the resultant RT-IL incorporating mononuclear [MnN(CN)4 ]2- molecules being a kinetic phase stabilized by inter-ion repulsions of the anionic divalent metal complex moieties. Water acts to decrease the coulombic interactions, including repulsion, giving rise to breaking of the coulombic ordering arising from coordination bond formation in the IL phase.

14.
Chemistry ; 25(23): 5875-5879, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30860310

RESUMO

Luminescent ZnII clusters [Zn4 L4 (µ3 -OMe)2 X2 ] (X=SCN (1), Cl (2), Br (3)) and [Zn7 L6 (µ3 -OMe)2 (µ3 -OH)4 ]Y2 (Y=I- (4), ClO4 - (5)), HL=methyl-3-methoxysalicylate, exhibiting blue fluorescence at room temperature (λmax =416≈429 nm, Φem =0.09-0.36) have been synthesised and investigated in detail. In one case the external heavy-atom effect (EHE) arising the presence of iodide counter anions yielded phosphorescence with a long emission lifetime (λmax =520 nm, τ=95.3 ms) at 77 K. Single-crystal X-ray structural analysis and time-dependent density-functional theory (TD-DFT) calculations revealed that their emission origin was attributed to the fluorescence from the singlet ligand-centred (1 LC) excited state, and the phosphorescence observed in 4 was caused by the EHE of counter anions having strong CH-I interactions.

15.
Dalton Trans ; 48(21): 7198-7202, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30637432

RESUMO

The 2D coordination polymers, [Mn(salen)]2[PtII(CN)4]1-x[PtIV(CN)4(I2)]x (salen = N,N'-ethylenebis(salicylideneaminato), x = 0.18 (1), 0.45 (2), 0.85 (3)), have been synthesized via consecutive oxidative additions of iodine to the 2D undulating layers in [Mn(salen)]2[PtII(CN)4]. The presence of I-Pt-I chains perpendicular to the layers and the inhomogeneity of individual I-Pt-I sites were demonstrated. The I-Pt-I chains in 3 give rise to an absorption band involving the excitation that arises from an antibonding nature orbital to the corresponding bonding nature orbital between iodides in the I-Pt-I bridging units. Moreover, variable-temperature X-ray powder diffraction patterns and Raman spectra for 1 and 2 indicate that some I-Pt-I sites display different vibrational energies that are associated with the contraction of the zigzag 2D layers.

16.
J Clin Neurosci ; 61: 302-304, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30385167

RESUMO

Diseases due to mutations of polymerase γ (POLG) usually present with progressive external ophthalmoplegia. However, a few studies have been reported on POLG1 mutations with the mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)-like phenotype. All cases with POLG1 mutations mimicking MNGIE have never shown leukoencephalopathy on brain magnetic resonance imaging (MRI) or demyelinating polyneuropathy. We present a 26-year-old male with gait disturbance, recurrent bowel obstruction, peripheral neuropathy, ophthalmoplegia or ptosis, which represented MNGIE phenotype. Though he displayed demyelinating peripheral neuropathy or leukoencephalopathy on brain MRI, genetic analysis revealed heterozygous mutation in POLG1 gene. We report for the first time two newly characteristics in our patient with heterozygous POLG1 mutations with the MNGIE-like phenotype: leukoencephalopathy and demyelinating polyneuropathy.


Assuntos
Polimerase do DNA Mitocondrial/genética , Pseudo-Obstrução Intestinal/diagnóstico , Pseudo-Obstrução Intestinal/genética , Leucoencefalopatias/diagnóstico , Leucoencefalopatias/genética , Encefalomiopatias Mitocondriais/diagnóstico , Encefalomiopatias Mitocondriais/genética , Adulto , Heterozigoto , Humanos , Imagem por Ressonância Magnética , Masculino , Distrofia Muscular Oculofaríngea , Mutação , Fenótipo
17.
Dalton Trans ; 47(46): 16422-16428, 2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30280733

RESUMO

Wheel-type heptanuclear heterometallic clusters of stoichiometry [Ni7-xMx(HL)6(µ3-OMe)4(µ3-OH)2]Cl2 (L = 1-(2-hydroxy-3-methoxybenzamido)-2-(benzylideneamino)ethane; M = Zn2+, Co2+, Mn2+; x = 1, 3) were synthesized, and their metal ion dependent ferromagnetic properties were investigated. It was demonstrated that the central position of each cluster was occupied by a Ni2+ ion while other metal ions (Zn2+, Co2+ or Mn2+) were accommodated in peripheral positions. The magnetic interactions, anisotropy and magnetization of the resultant clusters were all influenced by the combinations of metal ions present.

18.
J Alzheimers Dis ; 66(1): 289-296, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30248050

RESUMO

BACKGROUND: High-density lipoprotein (HDL) containing apolipoprotein A-I is associated with the pathogenesis of Alzheimer's disease (AD). HDL particle size is modified in the presence of pathological conditions, while the significance of the HDL particle size remains controversial. OBJECTIVE: The aim of this study was to investigate the HDL lipoprotein subclasses in mild cognitive impairment (MCI) and AD. METHODS: This cross-sectional study included 20 AD patients, 17 MCI patients, and 17 age-matched controls without cognitive impairment, selected from the database of the Study of Outcome and aPolipoproteins in Dementia (STOP-Dementia) registry. The diagnoses of AD and MCI were performed by expert neurologists according to the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition criteria. Serum HDL subclasses were measured by electrophoretic separation of lipoproteins using the Lipoprint System. The neutrophil-lymphocyte ratio (NLR), a marker of inflammation, was calculated by dividing the neutrophil count by the lymphocyte count. RESULTS: Small-sized HDL particle levels in the MCI group were significantly higher than in the control group, although there was no difference in serum HDL-cholesterol levels between MCI and control groups. NLR in the MCI group was higher than in the control group, but this difference was non-significant (p = 0.09). There was no difference in HDL subclasses or NLR between the AD and control groups. CONCLUSION: These findings suggest that HDL subclasses might be associated with the development of MCI.


Assuntos
Apolipoproteínas/sangue , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico por imagem , Demência/sangue , Demência/diagnóstico por imagem , Lipoproteínas HDL/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Disfunção Cognitiva/psicologia , Estudos Transversais , Demência/psicologia , Feminino , Humanos , Masculino , Resultado do Tratamento
19.
Inorg Chem ; 57(18): 11588-11596, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30188124

RESUMO

The ability to tune physical properties is attractive for the development of new materials for myriad applications. Understanding and controlling the structural dynamics in complicated network structures like coordination polymers (CPs) is particularly challenging. We report a series of two-dimensional CPs [Mn(salen)]2[M(CN)4]· xH2O (M = Pt (1), PtI2 (2), and MnN (3)) incorporating zigzag cyano-network layers that display composition-dependent anisotropic thermal expansion properties. Variable-temperature single-crystal X-ray structural analyses demonstrated that the thermal expansion behavior is caused by double structural distortions involving [Mn(salen)]+ units incorporated into the zigzag layers. Thermal relaxations produce structural transformations resulting in positive thermal expansion for 2·H2O and negative thermal expansion for 3. In the case of 1·H2O, the relaxation does not occur and zero thermal expansion results in the plane between 200 to 380 K. The present study proposes a new strategy based on structural distortions in coordination networks to control thermal responsivities of frameworks.

20.
Dalton Trans ; 47(39): 13809-13814, 2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30109314

RESUMO

The cobalt(ii) complex incorporating π-conjugated substituent, [Co(Naph-C2-terpy)2](BF4)2 (1; Naph-C2-terpy = 4'-(2-naphthoxy(ethoxy))-2,2':6',2''-terpyridine), exhibits an abrupt spin transition (ST) behavior (cooperative factor C = 0.91) while its solvated product, 1·2MeOH, shows gradual spin crossover (SCO) behavior (C = 0.49). Single crystal X-ray structural analyses demonstrated that the octahedral coordination core [CoN6] in 1 shows larger distortion in both high-spin and low-spin states than solvated 1·2MeOH or another two derivatives, [Co(R-terpy)2](BF4)2 (R = 2-naphthyl (2), 9-anthracenyl (3)). The respective distortion parameters (Σ) are compared with those for previously reported SCO cobalt(ii) compounds. The highly-distorted [CoN6] core in 1 (Σ = 126 in the HS state and 101.6 in the LS state) was stabilized by strong intermolecular interactions and observed an abrupt ST behaviour.

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