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1.
Dalton Trans ; 51(12): 4790-4797, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35253813

RESUMEN

Two novel luminescent metal-organic frameworks (MOFs), [Zn3(TCA)2(BPB)2]n (DZU-101, where H3TCA = 4,4',4''-tricarboxyltriphenylamine and BPB = 1,4-bis(pyrid-4-yl)benzene) and [Zn3(TCA)2(BPB)DMA]n (DZU-102), based on the same ligands and metal ions were synthesized by regulating the amount of water in the solvothermal reaction system. Structural analyses show that the two MOFs have pillar-layered frameworks with Zn3 clusters connected by the TCA3- and BPB ligands. Interestingly, DZU-102 possessed a two-fold interpenetrated framework distinct from the individual network of DZU-101. As a result, DZU-102 showed a visual fluorescence color change from chartreuse to azure in m-xylene, while the fluorescence color was turquoise in p-/o-xylene with no change. Furthermore, compared with p/o-xylene, the fluorescence emission peak of DZU-102 in m-xylene suspension produced an obvious blue shift. Moreover, selective fluorescence sensing experiments were also carried out, which demonstrated that the degree of peak shift was related to the concentration of m-xylene, indicating the potential application of DZU-102 in fluorescence sensing of m-xylene from xylene isomers and further revealed the application of structural interpenetration for luminescence tuning of MOFs.

2.
Opt Lett ; 44(20): 5053-5056, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31613261

RESUMEN

Here we theoretically demonstrate a dynamic third-harmonic generation (THG) device by incorporating chalcogenide phase change material (Ge2Sb2Te5) into ultra-small cavities of gap-plasmon resonators. Through coupling to plasmonic resonances, the THG efficiency of Ge2Sb2Te5 is increased up to five orders of magnitude due to the greatly enhanced electromagnetic fields within the ultra-small cavities. More interestingly, the THG signals of the proposed device can be dynamically switched on and off by tuning the phase states of Ge2Sb2Te5 between amorphous and crystalline. Our proposed dynamic THG nanostructures are beneficial to developing dynamic nonlinear nanophotonic devices.

3.
Mol Oncol ; 13(7): 1534-1547, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31099456

RESUMEN

Estrogens play a pivotal role in breast cancer etiology, and endocrine therapy remains the main first line treatment for estrogen receptor-alpha (ERα)-positive breast cancer. ER are transcription factors whose activity is finely regulated by various regulatory complexes, including histone deacetylases (HDACs). Here, we investigated the role of HDAC9 in ERα signaling and response to antiestrogens in breast cancer cells. Various Michigan Cancer Foundation-7 (MCF7) breast cancer cell lines that overexpress class IIa HDAC9 or that are resistant to the partial antiestrogen 4-hydroxy-tamoxifen (OHTam) were used to study phenotypic changes in response to ER ligands by using transcriptomic and gene set enrichment analyses. Kaplan-Meier survival analyses were performed using public transcriptomic datasets from human breast cancer biopsies. In MCF7 breast cancer cells, HDAC9 decreased ERα mRNA and protein expression and inhibited its transcriptional activity. Conversely, HDAC9 mRNA was strongly overexpressed in OHTam-resistant MCF7 cells and in ERα-negative breast tumor cell lines. Moreover, HDAC9-overexpressing cells were less sensitive to OHTam antiproliferative effects compared with parental MCF7 cells. Several genes (including MUC1, SMC3 and S100P) were similarly deregulated in OHTam-resistant and in HDAC9-overexpressing MCF7 cells. Finally, HDAC9 expression was positively associated with genes upregulated in endocrine therapy-resistant breast cancers and high HDAC9 levels were associated with worse prognosis in patients treated with OHTam. These results demonstrate the complex interactions of class IIa HDAC9 with ERα signaling in breast cancer cells and its effect on the response to hormone therapy.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Resistencia a Antineoplásicos , Antagonistas de Estrógenos/farmacología , Histona Desacetilasas/genética , Proteínas Represoras/genética , Neoplasias de la Mama/genética , Receptor alfa de Estrógeno/genética , Femenino , Humanos , Células MCF-7 , Transcriptoma/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
4.
Opt Lett ; 43(14): 3204-3207, 2018 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-30004532

RESUMEN

Manipulation of the photoluminescence (PL) of monolayer (ML) molybdenum disulfide (MoS2) with metallic plasmonic nanostructures has attracted much more attention for potential applications in optoelectronic devices. However, due to the limitation of resonance wavelength and oxidation properties, gold and silver are not the best selections for manipulating PL of MoS2. Here, we employ aluminum (Al) disks to tune the PL of ML MoS2. We have found that PL enhancement reaches the maximum when plasmonic resonances of Al disks overlap with the absorption peaks of ML MoS2. Near-field simulations show that PL enhancement is due to weak plasmon-exciton coupling.

5.
J Mater Chem B ; 4(7): 1276-1283, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32262983

RESUMEN

The development of ideal contrast agents was of great importance for multimodal imaging. However, the simple combination of different contrast components always needed long-time preparation and a tough reaction environment. In this study, we introduced a one-step microwave-assisted approach to synthesize lysozyme-capped gold nanoclusters (Lys-Au NCs) rapidly instead of traditional conditions. Irradiation with continuous microwave power shortened the reaction time from several hours to one hour and generated a large red shift (50 nm) of the fluorescence emission. The ultrasmall Lys-Au NCs showed excellent properties, including high quantum yield (19.61%), good stability, low cytotoxicity and good biocompatibility. This eco-friendly nanoprobe provided significant contrast signals in both NIRF (near-infrared fluorescence) and CT (X-ray computed tomography) in vivo imaging. Further conjugation with folic acid made the nanoprobe favorable for targeted fluorescence imaging of cancer cells and tumor-bearing mice.

6.
Asian Pac J Cancer Prev ; 15(13): 5181-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25040972

RESUMEN

Tumors have evolved numerous mechanisms by which they can escape from immune surveillance. One of these is to produce immunosuppressive cytokines. Transforming growth factor-ß(TGF-ß) is a pleiotropic cytokine with a crucial function in mediating immune suppression, especially in the tumor microenvironment. TGF-ß produced by T cells has been demonstrated as an important factor for suppressing antitumor immune responses, but the role of tumor-derived TGF-ß in this process is poorly understood. In this study, we demonstrated that knockdown of tumor-derived TGF-ß using shRNA resulted in dramatically reduced tumor size, slowing tumor formation, prolonging survival rate of tumor-bearing mice and inhibiting metastasis. We revealed possible underlying mechanisms as reducing the number of myeloid-derived suppressor cells (MDSC) and CD4+Foxp3+ Treg cells, and consequently enhanced IFN-γ production by CTLs. Knockdown of tumor-derived TGF-ß also significantly reduced the conversion of naive CD4+ T cells into Treg cells in vitro. Finally, we found that knockdown of TGF-ß suppressed cell migration, but did not change the proliferation and apoptosis of tumor cells in vitro. In summary, our study provided evidence that tumor-derived TGF-ß is a critical factor for tumor progression and evasion of immune surveillance, and blocking tumor-derived TGF-ß may serve as a potential therapeutic approach for cancer.


Asunto(s)
Neoplasias/inmunología , Neoplasias/patología , Factor de Crecimiento Transformador beta/inmunología , Animales , Apoptosis/inmunología , Linfocitos T CD4-Positivos/inmunología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Interferón gamma/inmunología , Masculino , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Monitorización Inmunológica , Células Mieloides/inmunología , Células Mieloides/patología , Tasa de Supervivencia , Linfocitos T Reguladores/inmunología
7.
Zhonghua Yi Xue Za Zhi ; 90(12): 808-12, 2010 Mar 30.
Artículo en Chino | MEDLINE | ID: mdl-20450618

RESUMEN

OBJECTIVE: To study the therapeutic effects and mechanism of saikosaponin-d (SSd) in mice with bleomycin (BLM)-induced pulmonary fibrosis. METHODS: According to the random number table, 180 mice were randomly divided into 5 groups. Four groups were pulmonary fibrosis models. Fibrosis model mice were established by intratracheal injection of bleomycin (5 mgxkg(-1)). They were BLM, DXM, SSd and SSd + DXM groups (n = 40 each). At 1 hour post-modeling, DXM, SSd and SSd + DXM groups were injected ip with dexamethasone (DXM, 5 mgxkg(-1)xd(-1), 0.1 ml), SSd (1.8 mgxkg(-1)xd(-1), 0.18 ml), DXM + SSd (0.28 ml) respectively qd until Day 28. BLM group was similarly dosed with normal saline. In addition, a normal control group (NC group, n = 20) treated likewise. The mice were anesthetized and sacrificed at Days 3, 7, 14, 28 for harvests of serum and lung tissue samples. The conventional histopathological changes of lung tissue were observed. Except for NC group, modeling groups of mice were used to observe the natural survival rate. Such indices as superoxide dismutase (SOD) and malonaldehyde (MDA) were examined both in lung tissue and serum samples. And hydroxyproline (HYP) was tested only in lung tissue. RESULTS: SSd could markedly increase the survival rate (80.0% in SSd and SSd + DXM groups vs 50.0% in BLM group, P < 0.05) and reduce alveolitis and fibrosis in mice. In comparison with BLM group, the levels of HYP of three treatment groups (DXM, SSd and SSd + DXM) in lung tissue was significantly lower (P < 0.05) at Days 14 and 28. The levels of MDA both in serum and lung tissue were significantly lower at Days 3, 7 and 14 (P < 0.05). The serum level of SOD was significantly higher at Days 3, 7 and 14 while the level of SOD in lung tissue was significantly higher at Days 3 and 7 (P < 0.05, P < 0.01). CONCLUSIONS: SSd has marked therapeutic effects upon bleomycin-induced pulmonary fibrosis in mice. And the mechanism may be associated with its anti-lipid peroxidation effect.


Asunto(s)
Ácido Oleanólico/análogos & derivados , Fitoterapia , Fibrosis Pulmonar/tratamiento farmacológico , Saponinas/uso terapéutico , Animales , Bleomicina/efectos adversos , Femenino , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos , Ácido Oleanólico/uso terapéutico , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/patología
8.
Inorg Chem ; 45(24): 9703-12, 2006 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-17112266

RESUMEN

A series of conjugated (porphinato)zinc(II)-based chromophores structurally related to [5-(4-dimethylaminophenylethynyl)-15-(5-nitrothienyl-2-ethynyl)-10,20-bis(3,5-bis(3,3-dimethyl-1-butyloxy)phenyl)]zinc(II) were synthesized using metal-catalyzed cross-coupling reactions involving [5-bromo-15-triisopropylsilylethynyl-10,20-diarylporphinato]zinc(II), [5-bromo-15-(4-dimethylaminophenylethynyl)-10,20-diarylporphinato]zinc(II), [5-(4-dimethylaminophenylethynyl)-15-ethynyl-10,20-diarylporphinato]zinc(II), and [5-(4-nitrophenylethynyl)-15-ethynyl-10,20-diarylporphinato]zinc(II), along with appropriately functionalized aryl, thienyl (or thiophenyl), thiazolyl, benzothiazolyl, and carbazolyl precursors. The linear and nonlinear optical properties of these asymmetrically 5,15-substitued-(10,20-diarylporphinato)zinc(II) chromophores that bear either 2-(9H-carbazol-9-yl)-thiophen-5-yl-ethynyl, 4-dimethylaminophenylethynyl, or 2-(N,N-diphenylamino)thiophen-5-yl-ethynyl electron-releasing groups and an electron-withdrawing group selected from 2-formyl-thiophen-5-yl-ethynyl, 2-(2,2-dicyanovinyl)-thiophen-5-yl-ethynyl, 4-nitrophenylethynyl, 6-nitrobenzothiazol-2-yl-ethynyl, or 5-nitrothiazol-2-yl-ethynyl are reported. The dynamic hyperpolarizabilities of these compounds were determined from hyper-Rayleigh light scattering measurements carried out at a fundamental incident irradiation wavelength (lambda(inc)) of 1300 nm; these measured beta1300 values ranged from 690 --> 1400 x 10(-30) esu. These data (i) show that these neutral dipolar molecules express substantial beta1300 values, (ii) highlight that reductions in the magnitude of the aromatic stabilization energy of (porphinato)metal-pendant arylethynyl groups have a significant impact upon the magnitude of the molecular hyperpolarizability, and (iii) provide insights into advantageous design modifications for closely related structures having potential utility in long-wavelength electrooptic applications.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(8): 1441-4, 2006 Aug.
Artículo en Chino | MEDLINE | ID: mdl-17058941

RESUMEN

Wavelet analysis (WT) was conducted on the simulated near infrared spectra (NIR) obtained by adding simulated background and simulated noise into diesel NIR Results show that the background components are mainly located in the low frequency region, while noise in the high frequency region, and useful signal in the middle frequency region. Background and noise components can be simultaneously subtracted from the spectra by WT. The WT coefficients in mid-frequency details can be selected as variables to build the multivariate calibration model, which can improve analytic accuracy and reduce the analysis time.


Asunto(s)
Simulación por Computador , Modelos Teóricos , Espectroscopía Infrarroja Corta/métodos , Espectroscopía Infrarroja Corta/normas , Algoritmos , Calibración , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(4): 516-20, 2005 Apr.
Artículo en Chino | MEDLINE | ID: mdl-16097674

RESUMEN

Derivative can correct baseline effects and also increase the level of noise. Wavelet transform has been proven an efficient tool for de-noising. This paper is directed to the application of wavelet transfer and derivative in the NIR analysis of octane number (RON). The derivative parameters, as well as their effects on the noise level and analytic accuracy of RON, have been studied in detail. The results show that derivative can correct the baseline effects and increase the analytic accuracy. Noise from the derivative spectra has great detriment to the analysis of RON. De-noising of wavelet transform can increase the S/N and improve the analytical accuracy.


Asunto(s)
Algoritmos , Gasolina/análisis , Octanos/análisis , Espectroscopía Infrarroja Corta/métodos , Gasolina/normas , Octanos/química , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador
11.
J Am Chem Soc ; 127(27): 9710-20, 2005 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-15998075

RESUMEN

An extensive series of conjugated (porphinato)zinc(II)-based chromophores featuring nitrothiophenyl and nitrooligothiophenyl electron-accepting moieties has been synthesized using metal-catalyzed cross-coupling reactions involving [5-bromo-15-triisopropylsilylethynyl-10,20-diarylporphinato]zinc(II) and an unusual electron-rich Suzuki-porphyrin synthon, [5-(4-dimethylaminophenylethynyl)-15-(4',4',5',5'-tetramethyl[1',3',2']dioxaborolan-2'-yl)-10,20-diarylporphinato]zinc(II), with appropriately functionalized aryl and thienyl precursors. These donor-acceptor chromophores feature thiophenyl, [2,2']bithiophenyl, and [2,2';5',2' ']terthiophenyl units terminated with a 5-nitro group; one series of structures features these acceptor moieties appended directly to the porphyrin macrocycle meso-carbon position, while a second set utilizes an intervening meso-ethynyl moiety to modify porphyrin-to-thiophene conjugation. The dynamic hyperpolarizability of these compounds was determined from hyper-Rayleigh light scattering (HRS) measurements carried out at fundamental incident irradiation wavelengths (lambda(inc)) of 800 and 1300 nm; interestingly, measured beta(1300) values ranged from 650 --> 4350 x 10(-30) esu. The combined linear and nonlinear optical properties of these compounds challenge the classical concept of the nonlinearity/transparency tradeoff in charge-transfer chromophores: the magnitude of the molecular hyperpolarizability is observed to vary substantially despite approximately uniform ground-state absorptive signatures for a given porphyrin-to-thiophene linkage topology. These data show that these neutral dipolar molecules can express substantial beta(1300) values; such conjugated, electronically asymmetric porphyrin-thiophene chromophores may thus find utility for electrooptic applications at telecom-relevant wavelengths.

12.
Zhonghua Nan Ke Xue ; 11(6): 455-7, 2005 Jun.
Artículo en Chino | MEDLINE | ID: mdl-15999494

RESUMEN

OBJECTIVE: To investigate the clinical characteristics, diagnosis and treatment of urinary neurofibrosarcoma. METHODS: Clinical data of 1 case of urinary neurofibrosarcoma was analyzed retrospectively and related literature reviewed. The 61-year old male patient had undergone TURP for benign prostate hyperplasia ten months before. RESULTS: Total urethral cavernostomy, total cystectomy and ileal cystostomy were performed on the patient and pathological diagnosis pointed to urinary neurofibrosarcoma. Another operation was done for metastatic rectal mass, which revealed abdominal metastasis. With progressing consumptive constitution, the patient died 40 days after the second operation. CONCLUSION: It is difficult to make a definite diagnosis in urinary neurofibrosarcoma, and the effective treatment for this highly malignant disease needs to be further studied.


Asunto(s)
Neurofibrosarcoma/diagnóstico , Neurofibrosarcoma/cirugía , Neoplasias Uretrales/diagnóstico , Neoplasias Uretrales/cirugía , Humanos , Masculino , Persona de Mediana Edad , Neurofibrosarcoma/patología , Estudios Retrospectivos , Neoplasias Uretrales/patología , Procedimientos Quirúrgicos Urológicos/métodos
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