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1.
Phys Chem Chem Phys ; 22(34): 19120-19130, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32808963

RESUMO

In organic multiferroics, the charge or spin coupled to the lattice induces lattice symmetry breaking, which is responsible for the ferroelectric (FE) transition. We propose a quantum spin model to describe the ferroelectricity of organic multiferroics, in which the pressure-driven spin-lattice coupling is controlled both by a jump function and a pressure power function. The T-p phase diagram shows different scaling relationships at low and high pressure regions, respectively, which is in accordance with the experimental observation. It is found that the pressure can not only enhance the FE polarization, but also enhance the transition temperature Tc as well as the electrocaloric effect (ECE). The electrocaloric critical scaling laws are proposed to verify the order and universality of the FE transition based on the Banerjee and Franco's criteria. In addition, we propose a temperature mediated mechanism within an isentropic process based on the ECE combined with the pyromagnetic effect, together with multiple physically (magnetic field and pressure jointly) controlled means, to enhance the magnetoelectric coupling around room-temperature, which will provide thermodynamic and quantum controlled means for realizing multi-state logic memory.

2.
Phys Chem Chem Phys ; 20(30): 20228-20234, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30028453

RESUMO

The cross-coupling between magnetic and ferroelectric orders in spin-driven organic multiferroics provides great potential for realizing multi-state logic memory. Creating strong magnetoelectric coupling around room-temperature is the key to eliminate the main roadblock for practical application. Herein, quantum correlation controlled means are employed to tune the transition temperature TC = 300 K, as the optimal operating temperature. After that, based on the magnetocaloric or electrocaloric effect, a temperature mediated mechanism is proposed to enhance magnetoelectric coupling within an isentropic rather than an isothermal process. Furthermore, a moderate magnetic field combined with a relatively weak electric field can jointly control and dramatically enhance the isentropic magnetoelectric coupling around room-temperature.

3.
Eur J Gynaecol Oncol ; 38(3): 350-355, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29693871

RESUMO

PURPOSE: To detect the expression of mucins in diverse benign and malignant cervical tissues of cervical disease. MATERIALS AND METHODS: 158 cases of cervical tissues were collected. Sections were stained with monoclonal antibodies against MUC1, MUC2, MIUC4, MUC5AC, and MUC20 by immunohistochemistry. RESULTS: Normal cervical epithelium showed high expr ession of MUC1I, MUC4, and MUC5AC, partial expression of MUC20, and no MUC2. With the development from chronic cervicitis, cervical intraepithelial neoplasia (CI7N) to cervical squamous cell carcinoma (SCC), the expression of MUC1, NMUC4, and MUC20 was statistically significant. The expression of MUCl was related with the depth of invasion and clinical stage of SCC. The positive rates of MUC4 and MUC20 were associated with the degree of differentiation and clinical stage of SCC. There was a correlation between the expression of MUC4, MUC 1, and MUC20 in cervical squamous lesions. CONCLUSION: Mucins may be involved in the development of cervical cancer.


Assuntos
Carcinoma de Células Escamosas/química , Mucinas/análise , Displasia do Colo do Útero/química , Neoplasias do Colo do Útero/química , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Colo do Útero/química , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
5.
Genet Mol Res ; 15(3)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27706761

RESUMO

This study aimed to determine whether abnormal apoptosis is present in acetabular cartilage in early developmental dislocations of the hip (DDH), and if so, whether it is correlated with the expression of caspase-3 and Bcl-2. DDH was induced in 24 4-week-old New Zealand white rabbits. Acetabular cartilage specimens from the experimental and control groups were stained with hematoxylin and eosin (H&E). Animals from the experimental group developed acetabular dysplasia. Apoptotic chondrocytes were observed by ultrastructural electron microscopy and H&E. TUNEL assays revealed significantly greater acetabular chondrocyte apoptosis in the treated samples as compared to the control. Significantly higher caspase-3 expression and lower Bcl-2 expression were also measured in the DDH group compared with the control. We conclude that excessive apoptosis does occur in acetabular cartilage with DDH, and is positively correlated with high caspase-3 expression as well as low Bcl-2 expression.


Assuntos
Acetábulo/patologia , Apoptose , Caspase 3/metabolismo , Condrócitos/enzimologia , Condrócitos/patologia , Luxação do Quadril/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Acetábulo/diagnóstico por imagem , Animais , Núcleo Celular/ultraestrutura , Forma Celular , Condrócitos/ultraestrutura , Cabeça do Fêmur/patologia , Luxação do Quadril/diagnóstico por imagem , Imobilização , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Coelhos , Coloração e Rotulagem
6.
Phys Chem Chem Phys ; 18(1): 510-8, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26617276

RESUMO

We study the magnetocaloric effect and the critical behavior of a periodic Anderson-like organic polymer using Green's function theory, in which the localized f orbitals hybridize with the conduction orbitals at even sites. The field-induced metal-insulator transitions with the magnetic Grüneisen parameter showing |Γh|∼T(-1) power-law critical behaviour are revealed, which provides a new thermodynamic means for probing quantum phase transitions. It is found that the competition of up-spin and down-spin hole excitations is responsible for the double peak structure of magnetic entropy change (-ΔS) for the dominant Kondo coupling case, implying a double magnetic cooling process via demagnetization, which follows a power law dependence of the magnetic field h: -ΔS∼h(n). The local exponent n tends to 1 and 2 below and above TC, while has a minimum of 0.648 at TC, which is in accordance with the experimental observation of perovskite manganites Pr0.55Sr0.45MnO3 and Nd0.55Sr0.45MnO3 (J. Y. Fan et al., Appl. Phys. Lett., 2011, 98, 072508; Europhys. Lett., 2015, 112, 17005) corresponding to the conventional ferromagnets within the mean field theory -ΔS∼h(2/3). At TC, the -ΔS∼h curves with a convex curvature superpose each other for small V values, which are separated by the large V case, distinguishing the RKKY interaction and Kondo coupling explicitly. Furthermore, the critical scaling law n(TC) = 1 + (ß- 1)/(ß + γ) = 1 + 1/δ(1 - 1/ß) is related to the critical exponents (ß, γ, and δ) extracted from the Arrott-Noakes equation of state and the Kouvel-Fisher method, which fulfill the Widom scaling relation δ = 1 + γß(-1), indicating the self-consistency and reliability of the obtained results. In addition, based on the scaling hypothesis through checking the scaling analysis of magnetization, the M-T-h curves collapse into two independent universal branches below and above TC.

7.
Eur Rev Med Pharmacol Sci ; 19(12): 2275-81, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26166654

RESUMO

Parkinsons Disease (PD) is a neurodegenerative disorder of the dopaminergic neurons in the substantia nigra. Much of the scientific literature on the Parkinson's disease has been focused on the evaluation and management of motor conditions in PD. Much less stress has been laid on evaluating and managing the cognitive disturbances found comorbidly in this condition. Studies have suggested that the cognitive dysfunction observed in PD can range anywhere from individual cognitive deficits to the clinical picture of minimal cognitive impairment to as much as a full-blown dementia like clinical picture. Perhaps because of this poor understanding, the treatments for this comorbidity have not been able to be adequately developed. Right now, only rivastigmine is the approved drug of choice for treatment of dementia associated with PD. In this review we aim at elaborating the individual cognitive deficits associated with PD instead of focusing on full-blown dementia. Our aim at focusing on individual symptoms is important because these symptoms should be evaluated even at the most beginning stages of PD rather than waiting for the patient to report for the symptoms. Therefore, we will aim at elaborating the prevalence, symptomatology and implications for treatment for these cognitive dysfunctions individually. Because covering all the domains of cognitive dysfunctions are not possible here, we will focus on three cognitive impairments which are most commonly observed in the PD patients. These are the (1) Executive function deficits (2) Memory deficits and (3) visuospatial deficits. We will, finally, have an overview of the condition of minimal cognitive deficits observed in PD.


Assuntos
Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Doença de Parkinson/diagnóstico , Doença de Parkinson/psicologia , Cognição/fisiologia , Transtornos Cognitivos/diagnóstico , Demência/diagnóstico , Demência/fisiopatologia , Demência/psicologia , Humanos , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/fisiopatologia , Doenças Neurodegenerativas/psicologia , Doença de Parkinson/fisiopatologia
8.
Eur Rev Med Pharmacol Sci ; 19(3): 402-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25720710

RESUMO

OBJECTIVE: To explore the clinical efficacy of aneurysm embolization and cerebrospinal fluid (CSF) replacement in the treatment of aneurysmal subarachnoid hemorrhage (SAH). PATIENTS AND METHODS: Seventy-nine patients with grade III-IV aneurysmal subarachnoid hemorrhage, who were treated in the hospital from Jan. 2012 to Jan. 2014, were included in this study. These patients were treated with different methods based on the cause of disease and the treatment chosen by their families. In the treatment group, 42 patients received aneurysm embolization and cerebrospinal fluid replacement, while 37 patients in the control group received simple aneurysm embolization. The treatment efficacy and the occurrence of complications in both groups were compared. RESULTS: The occurrence of cerebral vasospasm and hydrocephalus in the treatment group was significantly lower than the control group, and the difference was statistically significant. However, the mortality rate was decreased in both groups. CONCLUSIONS: Both methods had the advantage of minimal invasiveness and rapid post-operative recovery. But using combination of these two methods is clinically rational and could decrease the rate of disability and mortality.


Assuntos
Líquido Cefalorraquidiano , Embolização Terapêutica/normas , Hidratação/normas , Aneurisma Intracraniano/terapia , Hemorragia Subaracnóidea/terapia , Adulto , Idoso , Terapia Combinada/métodos , Terapia Combinada/normas , Embolização Terapêutica/métodos , Feminino , Hidratação/métodos , Humanos , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/diagnóstico , Resultado do Tratamento
9.
Clin Transl Oncol ; 16(10): 898-905, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24643702

RESUMO

PURPOSE: This study evaluated the effect of estrogen (E(2)), progesterone (P4), and the combination of them (E(2) + P4) on survival rate, apoptosis, and the expressions of Bcl-2, hsa-let-7a and has-miR-34b in primary ovarian cancer cells to provide new clues for the clinical treatments of ovarian cancer. METHODS: The primary ovarian cancer cells from 60 cases of clinical ovarian cancer tissues were isolated and then cultured. The survival rate of ovarian cancer cells after the treatment of E(2), P4 and E(2) + P4 was analyzed by MTT assay. Cell apoptosis rate and cell cycle were measured by FACS analysis. Moreover, the relative abundance of Bcl-2 and microRNAs (let-7a, miR-34b) expressions were detected by quantitative real-time PCR (qRT-PCR) and Western blotting. RESULTS: Low concentrations of estrogen (10(-10), 10(-8), 10(-6 )mol/L) did not affect the proliferation of ovarian cancer cells. However, the high concentration of estrogen (10(-4 )mol/L) inhibited survival rate of ovarian cancer cells. Progesterone (10(-4 )mol/L) inhibited the proliferation of cancer cells. The combination of estrogen and progesterone significantly inhibited the survival rate of ovarian cancer cells with a time- and dose-dependent manner. High concentration of estrogen combined with progesterone (E(2) + P4) induced apoptosis of ovarian cancer cells. E(2) + P4 promoted the expression of let-7a and miR-34b and reduced the expression of Bcl-2 in ovarian cancer cells. When the expression of let-7a or/and miR-34b was inhibited using miRNA inhibitors, E(2) + P4 treatment did not change the protein level of Bcl-2. CONCLUSION: E(2) + P4 significantly inhibited the cell survival, promoted the cell apoptosis, induced the expression of let-7a and miR-34b, and reduced the expression of Bcl-2 in ovarian cancer cells.


Assuntos
Adenocarcinoma de Células Claras , Proliferação de Células/efeitos dos fármacos , Estrogênios/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Ovarianas , Progesterona/farmacologia , Teratoma , Adenocarcinoma Mucinoso , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Feminino , Humanos , MicroRNAs/efeitos dos fármacos , MicroRNAs/genética , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Células Tumorais Cultivadas , Regulação para Cima
10.
Phys Chem Chem Phys ; 13(1): 328-36, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21031205

RESUMO

The zero- and low-temperature behaviors of a quasi-one-dimensional organic polymer proposed as a symmetrical periodic Anderson-like chain model, in which the localized f orbitals hybridize with the conduction orbitals at even sites, are investigated by means of many-body Green's function theory. In the absence of magnetic field, the ground state of the system turns out to be ferrimagnetic. The temperature-induced phase diagrams have been explored, where the competition between the Hubbard repulsion U on the localized f orbital and the hybridization strength V makes an important impact on the transition temperature. In a magnetic field, it is found that a 1/3 magnetization plateau appears and two critical fields indicating the insulator-metal transitions at zero temperature emerge, which are closely related to the energy bands. Furthermore, the single-site entanglement entropy is a good indicator of quantum phase transitions. The temperature-field-induced phase diagram has also been attained, wherein the magnetization plateau state, the gapless phase and the spin polarized state are revealed. The temperature dependence of thermodynamic quantities such as the magnetization, susceptibility and specific heat are calculated to characterize the corresponding phases. It is also found that the up-spin and down-spin hole excitations are responsible for the thermodynamic properties.


Assuntos
Magnetismo , Metais/química , Polímeros/química , Teoria Quântica , Termodinâmica
11.
Bone ; 47(1): 5-11, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20362079

RESUMO

In the present study, we systematically examined telmisartan, an angiotensin AT(1) receptor antagonist, on rosiglitazone-induced bone loss in ovariectomized spontaneously hypertensive rats. Telmisartan (5 mg/kg/d, 90 days) was found to be able to significantly alleviate rosiglitazone (10 mg/kg/d, 90 days)-induced decrease in BMD of femur and lumbar vertebrae. The BMD changes were associated with positive biomechanical changes of lumbar vertebrae, improvements in microarchitecture of tibial metaphysic and normalized serum osteocalcin (OC) levels and urinary deoxypyridinoline/creatinine (DPD/Cr) ratio. MicroCT analysis of the tibial metaphysis showed that telmisartan significantly prevented the decreases in bone volume/tissue volume (BV/TV), connect density (Conn. D.), trabecular number (Tb. N.) and trabecular thickness (Tb. Th.), and increase in trabecular separation (Tb. Sp.) induced by rosiglitazone. Histomorphometric analysis also showed that telmisartan had protective effects on rosiglitazone-reduced bone formation indices such as histomorphometric bone volume fraction (BV/TV-Histo), mineralizing surface/bone surface (MS/BS), mineral apposition rate (MAR) and bone formation rate (BFR/BS). Our study clearly showed that telmisartan alleviated rosiglitazone-induced bone loss in ovariectomized spontaneous hypertensive rats. The relief of bone loss provides a possible therapeutic application of telmisartan with rosiglitazone for the treatment of elderly women patients afflicted with metabolic syndrome.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Ovariectomia , Tiazolidinedionas/efeitos adversos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Biomarcadores/metabolismo , Fenômenos Biomecânicos/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Reabsorção Óssea/fisiopatologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/fisiopatologia , Ratos , Ratos Endogâmicos SHR , Rosiglitazona , Sístole/efeitos dos fármacos , Telmisartan , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/patologia , Tíbia/fisiopatologia , Fatores de Tempo , Microtomografia por Raio-X
12.
Phys Chem Chem Phys ; 11(48): 11415-23, 2009 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-20024411

RESUMO

We study the spin-Peierls (SP) transition of one-dimensional chain polymeric complexes coupled to lattice by means of many-body Green's function theory. The chain effective elastic constant is an intrinsic factor that determines the order of SP transition. It is found that the SP transition temperature T(SP) and the susceptibility-maximum temperature T(max) are in agreement with the experimental results. When an external magnetic field is applied to the chain, it makes T(SP) and T(max) decrease, and drives the SP transition from the second order to the first order. Besides, we show that the two-site thermal entanglement entropy is a good indicator of SP transition. Further considering the effect of interchain coupling on SP transition, with weak coupling of double-chain, the theoretical values are closer to the experimental results. We also calculate the density of states and spectral functions, which show that the energy gap vanishes at a critical temperature lower than T(SP), indicating a gapless SP phase lies in the gapped dimerized phase. The interchain coupling can drive the SP transition from the second order to the first order, while the SP dimerization may collapse for large interchain couplings.

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