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1.
Appl Opt ; 58(29): 8069-8074, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31674362

RESUMO

The optical properties of symmetric split-ring/ring dimer (SRRD) nanostructures composed of a small nanoring surrounded by an Ag splitting nanoring with a larger diameter are calculated theoretically. The apparent asymmetric Fano line shape in the spectra is related to fast switching of the bonding modes between the split-ring plasmon and ring dipole. The influence of the dimensions of the SRRD nanostructures on the spectral positions and intensity of Fano resonance is studied, and the asymmetric Fano line shape can be flexibly adjusted by varying the geometric parameters. In addition, relatively simple SRRD nanostructures have the same overall sensing figures of merit as conventional nanoparticles, thus rendering them suitable for high-performance optical sensors.

2.
Inorg Chem ; 58(22): 15573-15579, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31696701

RESUMO

Recent reports exposed an astonishing factor of high hardness that the connection between transition-metal (TM) atoms could enhance hardness, which is in contrast to the usual understanding that TM-TM will weaken hardness as the source of metallicity. It is surprising that there are two opposite mechanical characteristics in the one TM-TM bond. To uncover the intrinsic reason, we studied two appropriate mononitrides, CrN and WN, with the same light-element (LE) content and valence electron concentration. The two high-quality compounds were synthesized by a new metathesis under high pressure, and the Vickers hardness is 13.0 GPa for CrN and 20.0 GPa for WN. Combined with theoretical calculations, we found that the strong correlation of d electrons in TM-TM could seriously affect hardness. Thus, we make the complementary suggestions of the previous hardness factors that the antibonding d-electron state in TM-TM near the Fermi level should be avoided and a strong d covalent coupling in TM-TM is very beneficial for high hardness. Our results are very important for the further design of high-hardness and multifunctional TM and LE compounds.

3.
Appl Opt ; 58(23): 6308-6314, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503775

RESUMO

A bimetal-coated single-polarization photonic crystal fiber (PCF) filter based on surface plasmon resonance (SPR) with a liquid-filled structure is designed and calculated by the finite element method (FEM). The filter has many excellent properties. The y-polarized and x-polarized modes can simultaneously filter at 1310 nm and 1560 nm with unwanted losses 544.3 dB/cm and 147.3 dB/cm, respectively, corresponding to polarized losses as low as 12.3 dB/cm and 24.0 dB/cm. The filtering range can be tuned by adjusting the diameter of the outer air holes (d1), the diameter of the inner air holes (d2), and liquid refractive index n. The filtering ranges of x-polarization and y-polarization are 1550-1990 nm and 1310-1830 nm, respectively. The crosstalk (CT) values are 462.0 dB and -107.1 dB and corresponding available bandwidths are 224 nm and 504 nm at 1310 nm and 1560 nm, respectively.

4.
Appl Opt ; 58(18): 5082-5089, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503829

RESUMO

A silicon trimer is explored to tailor unidirectional forward scattering at multiple wavelengths in the near-infrared region with low loss using theoretical calculations and numerical simulations, which leads to the dramatic enhancement in unidirectional forward scattering and suppression of backward scattering. The higher moments in the trimer can be properly excited and balanced by breaking the symmetry of the trimer. The generalized Kerker conditions at two different wavelengths can be achieved in the trimer to further improve the scattering directivity. Our results provide insights into future development of all-dielectric low-loss nanoantennas in the near-infrared region.

5.
Opt Express ; 27(10): 14064-14074, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31163860

RESUMO

The enhanced photonic spin Hall effect (SHE) based on the D-shaped fiber with Ag-Ni alloy/silicon layers is proposed and theoretically investigated under excitation of surface plasmon resonance (SPR). In order to achieve the maximum transverse spin-dependent displacements for practical photonic devices, parameters such as the thickness of the Ag-Ni alloy and silicon layers in the D-shaped fiber are optimized. Theoretical modeling and numerical simulation demonstrate that the multilayer structure can effectively enhance the photonic SHE. The maximum transverse shift of 420 µm obtained with optimized parameters is larger than those in the literature. In addition, a maximum angular sensitivity of 114.6°/RIU is achieved by the wavelength interrogation method. Our concept and theoretical assessment suggest a novel and effective means to enhance the photonic SHE, bring us one step closer to the possibility to characterize parameters of dielectric layers by weak measurements, and accelerate the development of optical fibers based on the photonic SHE.

6.
Chemistry ; 25(19): 5051-5057, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30710382

RESUMO

Poor electrical conductivity severely limits the diverse applications of high hardness materials in situations where electrical conductivities are highly desired. A "covalent metal" TaB with metallic electrical conductivity and high hardness has been fabricated by a high pressure and high temperature method. The bulk modulus, 302.0(4.9) GPa, and Vickers hardness, 21.3 GPa, approaches and even exceeds that of traditional insulating hard materials. Meanwhile, temperature-dependent electrical resistivity measurements show that TaB possesses metallic conductivity that rivals some widely-used conductors, and it will transform into a superconductor at Tc =7.8 K. Contrary to common understanding, the hardness of TaB is higher than that of TaB2 , which indicates that low boron concentration borides could be mechanically better than the higher boron concentration counterparts. Compression behavior and first principles calculations denote that the high hardness is associated with the ultra-rigid covalent boron chain substructure. The hardness of TaB with different topologies of boron substructure shows that besides incorporating higher boron content, manipulating light element backbone configurations is also critical for higher hardness amongst transition metal borides with identical boron content.

7.
Phys Chem Chem Phys ; 21(5): 2697-2705, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30663734

RESUMO

The D7b-type structure Mn3B4 was fabricated by high-temperature and high-pressure (HPHT) methods. Hardness examination yielded an asymptotic Vickers hardness of 16.3 GPa, which is much higher than that of Mn2B and MnB2. First principle calculations and XPS results demonstrated that double zigzag boron chains form a strong covalent skeletons, which enhances this structure's integrity with high hardness. Considering that the hardensses of MnB and Mn3B4 are higher than those of Mn2B and MnB2, zigzag and double zigzag boron backbones are superior to isolated boron and graphite-like boron layer backbones for achieving higher hardness. This situation also states that a higher boron content is not the sole factor for the higher hardness in the low boron content transition metal borides. Futhermore, the co-presence of metallic manganese bilayers contribute to the high d-electron mobility and generate electrical conductivity and antiferromagnetism in Mn3B4 which provide us with a new structure prototype to design general-purpose high hardness materials.

8.
Drug Des Devel Ther ; 13: 183-203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30643386

RESUMO

Objective: To systematically evaluate the efficacy and safety of sodium cantharidinate and vitamin B6 (SC/B6) combined with conventional medical treatment (CMT) for the treatment of patients with advanced digestive system neoplasms (DSNs). Methods: The Cochrane Library, Embase, PubMed, Web of Science, Chinese Scientific Journal Database (VIP), China National Knowledge Infrastructure, and Wanfang databases were searched for clinical trials using SC/B6 for DSNs. Outcome measures, including therapeutic efficacy, quality of life (QoL), and adverse events, were extracted and systematically evaluated. Results: Data from 24 trials including 1,825 advanced DSN patients were included. Compared with CMT alone, its combination with SC/B6 significantly improved the patients' overall response rate (OR =2.25, 95% CI =1.83-2.76, P<0.00001), disease control rate (OR =2.41, 95% CI =1.85-3.15, P<0.00001), and QoL improvement rate (OR =2.75, 95% CI =2.13-3.55, P<0.00001). Moreover, adverse events caused by chemotherapy, including leukopenia, nausea and vomiting, gastrointestinal side effects, hepatotoxicity, diarrhea, transaminase disorder, myelosuppression, anorexia, and anemia, were significantly alleviated (P<0.05) when SC/B6 was applied to DSN patients. Nephrotoxicity, thrombocytopenia, hand-foot syndrome, and oral mucositis were not significantly alleviated in patients receiving combination therapy (P>0.05). Conclusion: The combination of SC/B6 and CMT is more effective in treating DSNs than CMT alone. This combination alleviates the adverse effects associated with chemotherapy and improves the QoL of DSN patients, and its application in the clinic is worth promoting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cantaridina/análogos & derivados , Neoplasias do Sistema Digestório/tratamento farmacológico , Segurança do Paciente , Vitamina B 6/uso terapêutico , Administração Oral , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cantaridina/administração & dosagem , Cantaridina/efeitos adversos , Cantaridina/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitamina B 6/administração & dosagem , Vitamina B 6/efeitos adversos
9.
Phys Chem Chem Phys ; 20(9): 6108-6115, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29442102

RESUMO

Hard materials are being investigated all the time by combining transition metals with light elements. Combining a structure search with first-principles functional calculations, we first discovered three stable stoichiometric C-rich ruthenium carbides in view of three synthesis routes, namely, the ambient phases of Ru2C3 and RuC, and two high pressure phases of RuC4. There is a phase transition of RuC4 from the P3[combining macron]m1 structure to the R3[combining macron]m structure above 98 GPa. The calculations of elastic constants and phonon dispersions show their mechanical and dynamical stability. The large elastic modulus, high Debye temperature and the estimated hardness values suggest that these hard ruthenium carbides have good mechanical properties. The analyses of electronic structure and chemical bonding indicate that chemical bonding, not carbon content, is the key factor for the hardness in these metallic C-rich ruthenium carbides. The partial covalent Ru-C bonds and strong covalent C-C bonds are responsible for the high hardness. Moreover, the emergence of partial covalent Ru-Ru bonds can enhance the hardness of RuC, while the ionic Ru-Ru bonds can weaken the hardness of Ru2C3.

10.
Inorg Chem ; 55(21): 11140-11146, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27786444

RESUMO

We report a robust honeycomb boron layers sandwiching manganese layers compound, MnB2, synthesized by high pressure and high temperature. First-principle calculation combined with X-ray photoelectron spectrum unravel that the honeycomb boron structure was stabilized by filling the empty π-band via grabbing electrons from manganese layers. Honeycomb boron layers sandwiching manganese layers is an extraordinary prototype of this type of sandwiched structure exhibiting electronic conductivity and ferromagnetism. Hydrostatic compression of the crystal structure, thermal expansion, and the hardness testing reveal that the crystal structure is of strong anisotropy. The strong anisotropy and first-principle calculation suggests that B-B bonds in the honeycomb boron structure are a strong directional covalent feature, while the Mn-B bonds are soft ionic nature. Sandwiching honeycomb boron layers with manganese layers that combine p-block elements with magnetic transition metal elements could endow its novel physical and chemical properties.

11.
BMC Cancer ; 16: 526, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27456503

RESUMO

BACKGROUND: This study was initiated to investigate the difference in HER2 status between tumor tissue and circulating tumor cells (CTCs), as well as the predictive value of CTC HER2 status for predicting the outcomes of anti-HER2 therapy in histologically HER2-positive metastatic breast cancer (MBC) patients. METHODS: HER2 expression on CTCs was detected using a CellSearch system within 7 days before a new line of anti-HER2 therapy was begun. According to the criterion proposed in our previous report, patients were defined as CTC HER2-positive or -negative. After close follow-up, the correlation between CTC HER2 status and the outcome of the treatment was evaluated by statistical analysis. RESULTS: CTCs were detected in 57.4 % (58/101) of the patients. Notably, 62.1 % (36/58) of these patients had an inconsistent HER2 status between their tissue and CTCs. The discordant rate may correlate with the time interval between histological and CTC HER2 testing and is more likely to occur in the subgroup of patients with an interval of > 1 year than in those with an interval < 1 year (70.7 % vs. 41.2 %, P = 0.043). For PFS, positive HER2 status on CTCs was shown to be a valuable predictor, both in univariate (HR = 0.321, 95%CI, 0.156-0.62, P = 0.0011) and multivariate (HR = 0.383, 95%CI, 0.166-0.831, P = 0.019) Cox regression analysis. Meanwhile, Kaplan-Meier survival curves revealed that the median PFS of CTC HER2-positive patients was significantly longer than CTC HER2-negative ones (8.5 vs. 3.5 months, P < 0.001). CONCLUSIONS: HER2 status on CTCs was different from that of tumor tissues and predicted a different outcome of the patients' anti-HER2 therapy. This difference may be correlated with the time interval between tissue and CTC HER2 testing, indicating the necessity of real-time HER2 analysis for histologically HER2-positive MBC patients.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Células Neoplásicas Circulantes/metabolismo , Receptor ErbB-2/metabolismo , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Resultado do Tratamento
12.
Phys Chem Chem Phys ; 18(27): 18074-80, 2016 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-27327210

RESUMO

Tantalum-boron compounds, which are potential candidates for superhard multifunctional materials, may possess multiple stoichiometries and structures under pressure. Using first-principle methods, ground-state TaB3 with the monoclinic C2/m space group and high-pressure TaB4 with the orthorhombic Amm2 space group have been found. They are more stable than the previously proposed structures. High-pressure boron-rich Amm2-TaB4 can be quenched to ambient pressure. The ground-state C2/m-TaB3 and high-pressure Amm2-TaB4 are two potential ultra-incompressible and hard materials with a calculated hardness of 17.02 GPa and 30.02 GPa at ambient pressure, respectively. Detailed electronic structure and chemical bonding analysis proved that the high hardness value of Amm2-TaB4 mainly stems from the strong covalent boron-boron bonds in graphene-like B layers as well as B-B bonds between layers.

13.
Clin Chim Acta ; 458: 23-9, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27109901

RESUMO

BACKGROUND: This study was initiated to evaluate the clinical significant of HER2 extracellular domain (ECD) in the real-time management of breast cancer patients. METHODS: Five-hundred forty-six eligible breast cancer patients were divided according to their clinical background. The correlation between ECD, tissue HER2, and clinical outcome of the patients were analyzed. RESULTS: Receiver operating characteristic analysis revealed that ECD measured before receiving neoadjuvant therapy yielded the highest area under the curve (0.9185; P<0.0001), indicating that ECD and tissue HER2 levels are consistent in untreated tumor-bearing patients. At cut-off of 15.0ng/ml, the prognostic value of ECD was demonstrated using univariate (HR=1.664, P<0.0001) and multivariate (HR=1.547, P=0.011) Cox regression analysis. Kaplan-Meier survival curves revealed that patients with elevated ECD had shorter progression-free survival (PFS) (4.0 vs. 6.1months, P<0.0001). Elevated ECD was also an adverse predictor for PFS in response to anti-HER2 therapy (4.3 vs. 10.2months, P=0.0155). In contrast, ≥20%, decreased ECD was associated with longer PFS in patients who received anti-HER2 therapy (10.9 vs. 2.4months, P=0.0164) and overall (10.7 vs. 2.8months, P=0.0034). CONCLUSIONS: A patient's clinical history can help determine whether ECD could provide added value for breast cancer management.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Receptor ErbB-2/sangue , Feminino , Humanos
15.
Clin Chim Acta ; 426: 102-7, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24055775

RESUMO

BACKGROUND: We investigated the clinical significance of serum bone-specific alkaline phosphatase (BAP), tartrate-resistant acid phosphatase isoform 5b (TRACP 5b) and type I collagen carboxyterminal telopeptide (ICTP) as bone metabolic markers for bone metastasis (BM) screening in lung cancer patients. METHODS: Newly diagnosed advanced lung cancer patients with (N = 130) and without (N = 135) BM were enrolled in the study. Serum BAP, TRACP 5b and ICTP were measured before the treatment. RESULTS: BAP, TRACP 5b and ICTP values were higher in patients with BM compared with patients without BM (all P < 0.0001). Area under ROC curve (AUC) of BAP, TRACP 5b and ICTP was 0.760, 0.753 and 0.835 (all P < 0.0001), respectively. The cut-off values for BAP, TRACP 5b and ICTP were 21.8 µg/l, 7.8 U/l and 8.8 µg/l, respectively. When TRACP 5b and ICTP were combined, AUC was elevated to 0.895 (P < 0.0001), and the cut-off values were TRACP 5b 7.6 U/l and ICTP 8.4 µg/l. CONCLUSIONS: We conclude that serum BAP, TRACP 5b and ICTP may serve as useful tools for BM screening in lung cancer patients.


Assuntos
Fosfatase Ácida/sangue , Fosfatase Alcalina/sangue , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/secundário , Colágeno Tipo I/sangue , Isoenzimas/sangue , Neoplasias Pulmonares/patologia , Peptídeos/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatase Ácida Resistente a Tartarato , Adulto Jovem
16.
Cell Stem Cell ; 11(5): 663-75, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23122290

RESUMO

In the mouse embryo, the aorta-gonad-mesonephros (AGM) region is considered to be the sole location for intraembryonic emergence of hematopoietic stem cells (HSCs). Here we report that, in parallel to the AGM region, the E10.5-E11.5 mouse head harbors bona fide HSCs, as defined by long-term, high-level, multilineage reconstitution and self-renewal capacity in adult recipients, before HSCs enter the circulation. The presence of hemogenesis in the midgestation head is indicated by the appearance of intravascular cluster cells and the blood-forming capacity of a sorted endothelial cell population. In addition, lineage tracing via an inducible VE-cadherin-Cre transgene demonstrates the hemogenic capacity of head endothelium. Most importantly, a spatially restricted lineage labeling system reveals the physiological contribution of cerebrovascular endothelium to postnatal HSCs and multilineage hematopoiesis. We conclude that the mouse embryonic head is a previously unappreciated site for HSC emergence within the developing embryo.


Assuntos
Embrião de Mamíferos/metabolismo , Endotélio Vascular/citologia , Células-Tronco Hematopoéticas/citologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Aorta/citologia , Aorta/embriologia , Caderinas/genética , Caderinas/metabolismo , Diferenciação Celular , Linhagem da Célula , Endotélio Vascular/embriologia , Gônadas/citologia , Gônadas/embriologia , Cabeça/irrigação sanguínea , Cabeça/embriologia , Células-Tronco Hematopoéticas/metabolismo , Mesonefro/citologia , Mesonefro/embriologia , Camundongos , Transgenes
17.
J Gastroenterol Hepatol ; 27(6): 1094-101, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22098296

RESUMO

BACKGROUND AND AIM: The pathogenesis of angiodysplasia is still not fully understood and effective therapy is not available. Thalidomide was reported to be effective in the treatment of angiodysplasia, but the mechanisms underlying its activity are, as yet, unknown. We aimed to investigate the expression of vascular endothelial growth factor (VEGF) in angiodysplasia tissues, and the role of hypoxia-inducible factor-1α (HIF-1α) and basic fibroblast growth factor (bFGF) on VEGF expression in human umbilical vein endothelial cells (HUVEC). Additionally, we aimed to study the role of thalidomide in these parameters. METHODS: Immunohistochemistry was performed to visualize VEGF in angiodysplasia lesions. HUVEC were incubated under hypoxic conditions or in the presence of bFGF. Effects of exposure to thalidomide were studied. Cell growth was assessed in methylthiazolyte-trazolium assays. Enzyme-linked immunosorbent assays and real-time polymerase chain reaction were performed to assess the expression of VEGF at protein and mRNA levels. Western blot was performed to detect the expression of HIF-1α under hypoxic conditions. RESULTS: VEGF was strongly expressed in 75% of patients with angiodysplasia lesions, as compared to expression in patients without angiodysplasia lesions. VEGF was also induced in HUVEC under hypoxic conditions (P < 0.05). bFGF was found to stimulate the proliferation of HUVEC and enhance the expression of VEGF. Thalidomide suppressed bFGF-induced proliferation significantly and decreased VEGF expression, both at the protein and mRNA levels. Thalidomide also inhibited HIF-1α in a dose-dependent manner (P < 0.05). CONCLUSIONS: VEGF may play an important role in the pathogenesis of angiodysplasia. Thalidomide can suppress VEGF, either induced by HIF-1α or bFGF.


Assuntos
Angiodisplasia/metabolismo , Inibidores da Angiogênese/farmacologia , Talidomida/farmacologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Adulto , Idoso , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto Jovem
18.
Gastroenterology ; 141(5): 1629-37.e1-4, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21784047

RESUMO

BACKGROUND & AIMS: Patients with recurrent bleeding from gastrointestinal vascular malformations are a challenge to treat. We investigated the long-term efficacy and safety of thalidomide for refractory bleeding from gastrointestinal vascular malformations in an open-label, randomized study. METHODS: Eligible patients were randomly assigned to groups that were given either 100 mg thalidomide (n = 28) or 400 mg iron (n = 27, controls), daily for 4 months; patients were followed for at least 1 year (mean, 39 months). Bleeding was defined by a positive result from an immunoassay fecal occult blood test. The primary end point was the effective response rate, defined as the proportion of patients in whom bleeding episodes had decreased by ≥ 50% in the first year of the follow-up period. The secondary end points included the rates of cessation of bleeding, blood transfusion, overall hospitalization, and hospitalization for bleeding. We also quantified yearly bleeding episodes, bleeding duration, levels of hemoglobin, and yearly requirements for transfusions of red cells, numbers of hospitalizations for bleeding, and hospital stays. Plasma levels of vascular endothelial growth factor were measured in the group given thalidomide. RESULTS: Rates of response in the thalidomide and control groups were 71.4% and 3.7%, respectively (P < .001). All secondary end points differed significantly different between groups; thalidomide was more effective. No severe adverse effects were observed, although minor side effects were common among patients in the thalidomide group. Levels of vascular endothelial growth factor were significantly reduced by thalidomide (P < .001). CONCLUSIONS: Thalidomide is an effective and relatively safe treatment for patients with refractory bleeding from gastrointestinal vascular malformations. Mechanisms of thalidomide activity might involve vascular endothelial growth factor.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Hemorragia Gastrointestinal/tratamento farmacológico , Hemorragia Gastrointestinal/etiologia , Talidomida/uso terapêutico , Malformações Vasculares/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Ferro/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Talidomida/efeitos adversos , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/sangue
19.
Asian Pac J Cancer Prev ; 12(12): 3433-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22471493

RESUMO

The zinc-finger factor Snai1 plays an important role in the down-regulation of E-cadherin expression and in the induction of epithelial-mesenchymal transition (EMT) during cancer progression. In gastric cancer tissues, we noted that Snail is abnormally high expressed and is remarkably associated with the lymph node metastasis. Using a plasmid containing newly synthesized artificial microRNA (amiRNA), we transfected gastric cancer cells to block Snail expression. Both Snail protein and mRNA levels were significantly decreased in stably transfected cells, while protein and mRNA expression of E-cadherin was up-regulated. In addition, migration and invasion potential were significantly decreased after knockdown of Snail.


Assuntos
Caderinas/metabolismo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/prevenção & controle , Fatores de Transcrição/genética , Western Blotting , Caderinas/genética , Adesão Celular , Movimento Celular , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Invasividade Neoplásica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Neoplasias Gástricas/patologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas , Dedos de Zinco
20.
Zhonghua Nei Ke Za Zhi ; 48(4): 295-8, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19576118

RESUMO

OBJECTIVE: To investigate the inhibitory effect of thalidomide on angiodysplasia. METHODS: Excisional intestinal specimens were collected and immunohistochemical examination was carried out. The human umbilical vein endothelial cells were cultured in vitro to exponential phase of growth, divided into six groups and synchronized for 24 hours. They were then stimulated with thalidomide (40 - 100 microg/ml) for 72 hours. MTT assay was used to assess cellular proliferation. ELISA, real-time quantitative PCR and western blot were applied to detect the expression of VEGF/HIF-1alpha of human umbilical vein endothelial cells (HUVEC). RESULTS: Immunohistochemical analysis of intestinal pathological specimens demonstrated higher expression of VEGF. ELISA showed that the expression of VEGF under hypoxia was obviously higher than that under normoxia [(1199.3 +/- 61.4) ng/L vs (864.7 +/- 41.2) ng/L, P < 0.05]. Real-time quantitative PCR and Western blot discovered that thalidomide inhibited the expression of VEGF/HIF-1alpha of HUVEC (P < 0.05). The effect of thalidomide was dose-dependent. CONCLUSIONS: Thalidomide can suppress the expression of HIF-1alpha and VEGF in HUVEC in vitro and then inhibit angiodysplasia, which may play a significant role in stopping the rebleeding in patients with recurrent gastrointestinal bleeding.


Assuntos
Angiodisplasia/patologia , Células Endoteliais/efeitos dos fármacos , Talidomida/farmacologia , Angiodisplasia/etiologia , Angiodisplasia/metabolismo , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
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