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1.
Inorg Chem ; 59(5): 2811-2824, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32052960

RESUMO

A family of chiral 3d-4f heterometallic complexes, namely, [Zn2Ln(R,R-L)2(H2O)4](ClO4)3) [Ln = Dy (1), Tb (3)], [Zn2Ln(S,S-L)2(H2O)4](ClO4)3 [Ln = Dy (2), Tb (4)], [Zn2Ln2(R,R-L)2(CO3)2(NO3)2]·2CH3OH [Ln = Dy (5), Tb (7)], and [Zn2Ln2(S,S-L)2(CO3)2(NO3)2]·2CH3OH [Ln = Dy (6), Tb (8)] {H2L = cyclohexane-1,2-diylbis(azanediyl)bis(methylene)bis(2-methoxyphenol)}, has been synthesized and characterized. Crystal structure analysis reveals that complexes 1-4 are isostructural trinuclear clusters crystallized in chiral space group C2221, and 5-8 are isostructural tetranuclear clusters crystallized in chiral space group P1. Interestingly, the adjacent [ZnLn] units within the tetranuclear cluster in 5-8 are bridged by two carbonate anions via in situ incorporation of CO2 from air. Magnetic measurements indicate that complexes 1 and 3 exhibit field-induced single-molecule magnet behavior with energy barriers (Ueff) of 22.46 and 38.70 K (or 41.87 K), respectively. Complex 5 displays typical SMM behavior with Ueff = 19.61 K under zero dc field, while for complex 7, no obvious out-of-phase signals are observed even under 2 kOe dc field, the absence of SMM behavior. The solid-state luminescence studies reveal that all complexes display the characteristic fluorescence emission of lanthanide ions. Furthermore, the Kurtz-Perry measurements reveal these complexes are potential nonlinear optical materials.

2.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 44(3): 329-34, 2015 05.
Artigo em Zh | MEDLINE | ID: mdl-26350015

RESUMO

OBJECTIVE: To investigate the mRNA and protein expression levels of S100A8 and S100A9 in giant cell tumor (GCT) of bone, and its relation with radiological findings and biological behavior. METHODS: Forty three patient with GCT of bone admitted in Ruijin Hospital Shanghai Jiaotong University School of Medicine from January 2009 to June 2012 were enrolled in the study. The expression levels of S100A8 and S100A9 mRNA and protein were detected by using semiquantitative RT-PCR and Western blotting in 43 specimens of GCT and 6 specimens of normal bone marrow. The CT and MRI findings of patients were retrospectively reviewed, its relation with tissue expression of S100A8 and S100A9 was analyzed. RESULTS: Among 43 GCT cases 40 showed positive expression of S100A8 and S100A9 mRNA and protein, and the expression levels were significantly higher than those in normal bone marrow P<0.05). The expression level of S100A8 protein was significantly different in bone GCT with different composition ratio on MRI (P<0.05).The expression level of S100A9 protein was significantly different in GCT with different degree of bone destruction on CT scan (P<0.05). CONCLUSION: The expression of S100A8 and S100A9 mRNA and protein is up-regulated in GCT of bone. The expression of S100A8 and S100A9 is associated with the real composition ratio and the degree of bone destruction, respectively, indicating that S100A8 and S100A9 may be involved in the biological behavior of bone GCT.


Assuntos
Neoplasias Ósseas/metabolismo , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Tumor de Células Gigantes do Osso/metabolismo , China , Humanos , RNA Mensageiro , Tomografia Computadorizada por Raios X , Regulação para Cima
3.
Radiol Med ; 118(3): 456-64, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22872452

RESUMO

PURPOSE: This study was done to investigate X-ray, computed tomography (CT) and magnetic resonance (MR) imaging features of recurrence in giant cell tumour of bone (GCTB) and to evaluate risk factors. MATERIALS AND METHODS: Medical records and imaging data were reviewed for 55 cases of recurrent GCTB. All images were reviewed retrospectively and independently by two radiologists experienced in skeletal musculature. The common radiological findings; factors related to tumour recurrence such as gender, age, location; pathological fracture, Campanacci grading and surgical procedure were analysed by nonparametric test (Mann-Whitney U test for two independent samples test and Kruskal-Wallis H test for multiple independent samples test). p values <0.05 were considered to indicate a statistically significant difference. RESULTS: The imaging features of recurrent GCTB were as follows: osteolytic destruction or bone resorption of graft bone or around the polymethylmethacrylate (PMMA), soft tissue mass formation and expansile change. Tumour parenchyma showed markedly heterogeneous enhancement, except for necrotic cystic cavities, on contrast-enhanced MR images. Wide resection had a smaller (p=0.031) risk of local recurrence than did intralesional curettage. There was no statistical significance in gender, age, location, pathological fracture and Campanacci staging (p>0.05). CONCLUSIONS: The risk of recurrence in GCTB was influenced by the type of surgery and adjuvants. Bone transformaresorption, soft tissue mass formation and aggravated expansile change are reliable signs of recurrence on imaging.


Assuntos
Neoplasias Ósseas/patologia , Tumor de Células Gigantes do Osso/patologia , Imageamento por Ressonância Magnética/métodos , Recidiva Local de Neoplasia/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/terapia , Distribuição de Qui-Quadrado , Feminino , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Tumor de Células Gigantes do Osso/terapia , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico por imagem , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco , Estatísticas não Paramétricas
4.
Radiol Med ; 118(8): 1324-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23716292

RESUMO

PURPOSE: The purpose of this study was to review the clinical presentation, imaging, pathology and outcome of patients with giant cell-rich osteosarcoma (GCRO) of long bones. MATERIALS AND METHODS: Radiography (n=9), magnetic resonance imaging (MRI) (n=6), computed tomography (CT) (n=3) and clinical course of nine patients (five males and four females; mean age, 26 years) with pathologically confirmed GCRO were retrospectively reviewed. Specific imaging findings, including size, eccentricity, ossification, lysis, cystic change, expansile growth, periosteal reaction, cortical destruction, soft tissue extension and joint involvement were documented. RESULTS: Presenting symptoms were pain in six patients and pain and palpable mass in three. An ill-defined margin surrounding a predominantly osteolytic lesion was detected at the proximal tibia (n=7) or femur (n=2) on imaging studies. Seven cases showed limited ossification. Three cases had tumours in the metaphysis and six in the metaepiphysis. The average maximum tumour dimension was 4.7 cm×5.2 cm×7.8 cm. Microscopically, tumours were composed of atypical cells with scanty osteoid formation and multinucleated giant cells. All patients received chemotherapy, and surgery was performed in eight patients. Three patients were dead and six were alive at the last follow-up. CONCLUSIONS: GCRO is a rarer variant that has very close resemblance to giant cell tumour. Patients usually present nonspecific symptoms of pain and palpable mass. It usually shows an osteolytic lesion with locally spared new bone formation in the metaphysis and/or metaepiphysis on imaging. Histologically, the atypical tumour cells with osteoid formation and multinucleated giant cells are the key factor in the diagnosis and differential diagnosis.


Assuntos
Diagnóstico por Imagem , Neoplasias Femorais/diagnóstico , Tumor de Células Gigantes do Osso/diagnóstico , Osteossarcoma/diagnóstico , Tíbia/patologia , Adolescente , Adulto , Diagnóstico Diferencial , Feminino , Neoplasias Femorais/patologia , Tumor de Células Gigantes do Osso/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/patologia , Estudos Retrospectivos
5.
Dalton Trans ; 53(1): 339-345, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38050406

RESUMO

Revealing the stimuli-responsive mechanism is the key to the accurate design of stimuli-responsive luminescent materials. We report herein the multistimuli-responsive multicolor solid-state luminescence of a new dicopper(I) complex [{Cu(bpmtzH)}2(µ-dppa)2](ClO4)2 (1), and the multistimuli-responsive mechanism is clarified by investigating its four different solvated compounds 1·2CH3COCH3·2H2O, 1·2DMSO·2H2O, 1·4CH3OH, and 1·4CH2Cl2. It is shown that luminescence mechanochromism is associated with the breakage of the hydrogen bonds of bmptzH-NH with counter-ions such as ClO4- induced by grinding, while luminescence vapochromism is attributable to the breaking and forming of hydrogen bonds of dppa-NH with solvents, such as acetone, dimethylsulfoxide, and methanol, caused by heating and vapor fuming. In addition, those results might provide new insights into the design and synthesis of multistimuli-responsive multicolor luminescent materials by using various structure-sensitive functional groups, such as distinct N-H ones, to construct switchable hydrogen bonds.

6.
Dalton Trans ; 46(4): 1153-1162, 2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28054063

RESUMO

A new family of 3d-4f heterometallic trinuclear complexes, namely [M2LnL2]·2ClO4·H2O (H3L = tris(((2-hydroxy-3-methoxybenzy1)amino)ethyl)amine, where M = Ni, Ln = Gd (1), Dy (2), and M = Zn, Ln = Gd (3), Dy (4)) were synthesized via the reaction of H3L and Ln(NO3)3·6H2O and Ni(ClO4)2·6H2O or Zn(ClO4)2·6H2O in a 2 : 1 : 2 ratio in the solution. Complexes 1-4 consisted of three metal ions arranged in an isosceles triangle manner. Magnetic properties investigations showed that complexes 1 and 2 exhibited weak ferromagnetic coupling between the Ni(ii) and Ln(iii) ions, whereas complex 4 displayed lanthanide single-ion magnetic properties. The alternating current (ac) magnetic susceptibilities of 4 revealed that both the in-phase (χ') and out-of-phase (χ'') signals are frequency- and temperature-dependent, which are typical features of the field-induced slow relaxation of the magnetization with Ueff = 124.5 K. Complex 4 also exhibited an obvious butterfly-shaped hysteresis loop at 2 K, indicating that it is a single-ion magnet. Moreover, complex 4 showed stronger fluorescent emissions, which were typical narrow emission bands of lanthanide ions. Therefore, complex 4 can be considered as a molecular magnetic and luminescent material. Comparably, complex 2 showed very weak DyIII-based emissions because the paramagnetic NiII ions quench the fluorescence and thereby lower the population of the triplet state.

7.
Dalton Trans ; 46(1): 64-70, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27942632

RESUMO

By using Gd2O3, propanedioic acid (H2pda) and oxalic acid (H2ox), a new Gd-based metal-organic framework (MOF) [Gd(pda)(ox)0.5(H2O)2]n (1) has been successfully constructed and structurally characterized. Interestingly, temperature- and vapor-induced reversible single-crystal-to-single-crystal transformations occurred and two new MOFs, namely [Gd(pda)(ox)0.5(H2O)]n (1a) and [Gd(pda)(ox)0.5]n (1b), have been obtained. Complex 1 displays a two-dimensional (2D) layer structure composed of zigzag [Gd(pda)]n chains and it could also be made up of numerous Gd6 macrocycles. Thermal dehydration leads to more complicated three-dimensional (3D) 'pillar-layer' structures (1a and 1b) with the same coordination mode of pda2- anions. Magnetic studies suggest the presence of ferromagnetic couplings between the intrachain or intralayer GdIII ions and large magnetocaloric effects (MCEs) with -ΔS = 45.0 J kg-1 K-1 (1), 46.1 J kg-1 K-1 (1a) and 46.8 J kg-1 K-1 (1b) under a 7 T applied field. Therefore, the interest of 'robust magnetocaloric MOFs' is now extended to compounds showing weak ferromagnetic couplings and hence having better magnetocaloric performances for small field changes.

8.
Dalton Trans ; 45(22): 9209-15, 2016 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-27171744

RESUMO

Two Gd(III) coordination polymers with the formula [Gd(cit)(H2O)]∞ () and [Gd(nta)(H2O)2]∞ () (H4cit = citric acid, H3nta = nitrilotriacetic acid) have been successfully prepared under hydrothermal conditions. Complex exhibits a three-dimensional (3D) structure based on carboxylate-bridged layers, while complex is a double-layer structure containing eight-coordinated Gd(III). Magnetic investigations reveal that weak antiferromagnetic couplings between adjacent Gd(III) ions in both and with different Weiss values result in large cryogenic magnetocaloric effects. It is notable that the maximum entropy changes (-ΔS) of and reach 31.3 J kg(-1) K(-1) and 32.2 J kg(-1) K(-1) at 2 K for a moderate field change (ΔH = 3 T), and a remarkable -ΔS (41.5 J kg(-1) K(-1) for and 42.0 J kg(-1) K(-1) for ) could be obtained for ΔH = 7 T.

9.
Eur J Radiol ; 81(11): 3397-403, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22537981

RESUMO

OBJECTIVE: This study aims to assess retrospectively the imaging features of diaphyseal osteosarcoma and compare its characteristics with that of metaphyseal osteosarcoma. MATERIALS AND METHODS: Eighteen pathologically confirmed diaphyseal osteosarcomas were reviewed. Images of X-ray (n=18), CT (n=12) and MRI (n=15) were evaluated by two radiologists. Differences among common radiologic findings of X-ray, CT and MRI, and between diaphyseal osteosarcomas and metaphyseal osteosarcomas in terms of tumor characteristics were compared. RESULTS: The common imaging features of diaphyseal osteosarcoma were bone destruction, lamellar periosteal reaction with/without Codman triangle, massive soft tissue mass/swelling, neoplastic bone and/or calcification. CT and MRI had a higher detection rate in detecting bone destruction (P=0.001) as compared with that of X-ray. X-ray and CT resulted in a higher percentage in detecting periosteal reaction (P=0.018) and neoplastic bone and/or calcification (P=0.043) as compared with that of MRI. There was no difference (P=0.179) in detecting soft tissue mass among three imaging modalities. When comparing metaphyseal osteosarcoma to diaphyseal osteosarcoma, the latter had the following characteristics: a higher age of onset (P=0.022), a larger extent of tumor (P=0.018), a more osteolytic radiographic pattern (P=0.043). CONCLUSION: As compared with metaphyseal osteosarcoma, diaphysial osteosarcoma is a special location of osteosarcoma with a lower incidence, a higher age of onset, a larger extent of tumor, a more osteolytic radiographic pattern. The osteoblastic and mixed types are diagnosed easily, but the osteolytic lesion should be differentiated from Ewing sarcoma. X-ray, CT and MRI can show imaging features from different aspects with different detection rates.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Osteossarcoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
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