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1.
Opt Express ; 31(16): 25477-25489, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710433

RESUMO

Broader spectra, lower reflectivity and higher reliability are the performance requirements for broadband antireflective (BBAR) films. In this work, a BBAR film structure was proposed, which maintains extremely low reflectivity, ultra-wide spectra, low polarization sensitivity and practical reliability. The BBAR film consists of a dense multilayer interference stack on the bottom and a nano-grass-like alumina (NGLA) layer with a gradient low refractive index distribution on the top. The film was deposited by atomic layer deposition, while the NGLA layer was formed by means of a hot water bath on Al2O3 layer. The top NGLA layer has extremely high porosity and ultra-low refractive index, along with extremely fragile structure. To surmount the fragility of NGLA layer, a sub-nano layer of SiO2 was grown by atomic layer deposition to solidify its structure and also to adjust the refractive index with different thicknesses of SiO2. Finally, in the wide wavelength range of 400-1100 nm, the average transmittance of the double-sided coated fused quartz reaches 99.2%. The absorption, light scattering, reliability and polarization characteristics of BBAR films were investigated. An optimized BBAR film with low polarization-sensitivity and improved reliability was realized, which should be potentially promising for application in optical systems.

2.
Cancer ; 127(17): 3163-3171, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34043812

RESUMO

BACKGROUND: The authors aimed to investigate the efficacy and safety of apatinib in patients with metastatic or locoregionally recurrent nasopharyngeal carcinoma (NPC). METHODS: A multicenter, single-arm, prospective phase 2 study was conducted on patients (18-70 years of age) with metastatic or recurrent NPC who had failed chemotherapy. Patients with recurrent disease involving vascular structure invasion were excluded. All enrolled patients received apatinib (500 mg daily) in continuous 4-week cycles until disease progression or development of unacceptable toxicity. The primary end point of this study was objective response rate (ORR), and the secondary end points were progression-free survival (PFS), overall survival (OS), and toxicity. This study was registered with ClinicalTrials.gov (NCT03130270). RESULTS: Between January 2017 and June 2018, 33 patients were enrolled. At the end of the data collection (May 20, 2020), the 33 patients had completed a total of 261.2 cycles of apatinib. Although 12 patients achieved a partial response, no patient achieved a complete response; thus, the ORR in the 33 patients was 36.4% (95% CI, 19.0%-53.7%). At the end of follow-up (median, 30 months; 95% CI, 24.9-35.1), median OS and median PFS were 16 months (95% CI, 14.6-17.4 months) and 5.0 months (95% CI, 3.6-6.4 months), respectively. The most common adverse events (grade 1/2) were hand-foot syndrome (18 [54.5%]), hypertension (14 [42.4%]), oral ulcer (8 [24.2%]), and proteinuria (4 [12.1%]). Two patients (1 with diabetes and 1 with hypertension) developed cerebral infarction. Grade 3/4 toxicities were uncommon. CONCLUSIONS: Apatinib shows promising activity, with manageable toxicities, in patients with metastatic or locoregionally recurrent NPC. Further evaluation of apatinib in large-scale studies is warranted. LAY SUMMARY: Clinical studies on vascular endothelial growth factor receptor (VEGFR)-targeted therapy for recurrent or metastatic nasopharyngeal carcinoma (NPC) are limited. A recent preclinical study that evaluated apatinib in models of NPC showed a high objective response rate and a favorable safety profile. Our data further confirmed good efficacy in patients with lung metastasis. Further studies of the efficacy and safety of apatinib combined with immune checkpoint inhibitors or chemotherapy in NPC is warranted.


Assuntos
Antineoplásicos , Neoplasias Nasofaríngeas , Antineoplásicos/uso terapêutico , Humanos , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estudos Prospectivos , Piridinas , Fator A de Crescimento do Endotélio Vascular
3.
Hepatobiliary Pancreat Dis Int ; 20(4): 345-351, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33753000

RESUMO

BACKGROUND: Positron emission tomography (PET) imaging is a non-invasive method to visualize and quantify the tumor microenvironment. This study aimed to explore the feasibility of 18F-AIF-NOTA-E[PEG4-c(RGDfk)]2 (denoted as 18F-RGD) PET quantitative parameters to distinguish the angiogenesis in colorectal cancer (CRC) mice which has different metastatic potential. METHODS: Twenty LoVo and twenty LS174T of CRC liver metastases animal models were established by implantation of human CRC cell lines via intrasplenic injection. Radiotracer-based micro-PET imaging of animal model was performed and the uptake of 18F-RGD tracer in the tumor tissues was quantified as tumor-to-liver maximum or mean standardized uptake value (SUVmax or SUVmean) ratio. Pearson correlation was used to analyze the relationship between radioactive parameters and tumor markers. RESULTS: The SUVmax and SUVmean ratios of LoVo model were significantly higher than those of LS174T in both liver metastasis and primary tumor lesions (P < 0.05). A significant difference was observed in both vascular endothelial growth factor (VEGF) and Ki67 expressions between LoVo and LS174T primary tumors (P < 0.05). The tumor-to-liver SUVmax or SUVmean ratio of 18F-RGD showed a moderate correlation with VEGF expression (r = 0.5700, P = 0.001 and r = 0.6657, P < 0.001, respectively), but the SUVmean ration showed a weak correlation with Ki67 expression (r = 0.3706, P < 0.05). The areas under the receiver operating characteristic (ROC) curves of 18F-RGD SUVmean ratio, SUVmax ratio for differentiating LoVo from LS174T tumor were 0.801 and 0.759, respectively. CONCLUSIONS: The tumor-to-liver SUVmean ratio of 18F-RGD was a promising image parameter for the process of monitoring tumor angiogenesis in CRC xenograft mice model.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Neoplasias Colorretais/diagnóstico por imagem , Fluordesoxiglucose F18 , Antígeno Ki-67 , Neoplasias Hepáticas/diagnóstico por imagem , Camundongos , Neovascularização Patológica/diagnóstico por imagem , Oligopeptídeos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular
4.
Opt Express ; 27(3): 3161-3168, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732341

RESUMO

Sub-bandgap near-infrared silicon (Si) photodetectors are key elements in integrated Si photonics. We demonstrate such a Si photodetector based on a black Si (b-Si)/Ag nanoparticles (Ag-NPs) Schottky junction. This photodetector synergistically employs the mechanisms of inner photoemission, light-trapping, and surface-plasmon-enhanced absorption to efficiently absorb the sub-bandgap light and generate a photocurrent. The b-Si/Ag-NPs sample was prepared by means of wet chemical etching. Compared to those of a planar-Si/Ag thin-film Schottky photodetector, the responsivities of the b-Si/Ag-NPs photodetector were greatly enhanced, being 0.277 and 0.226 mA/W at a reversely biased voltage of 3 V for 1319- and 1550-nm light, respectively.

5.
Hepatobiliary Pancreat Dis Int ; 18(2): 164-172, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30850340

RESUMO

BACKGROUND: Positron emission tomography (PET) imaging is a non-invasive functional imaging method used to reflect tumor spatial information, and to provide biological characteristics of tumor progression. The aim of this study was to focus on the application of 18F-fluoromisonidazole (FMISO) PET quantitative parameter of maximum standardized uptake value (SUVmax) ratio to detect the liver metastatic potential of human colorectal cancer (CRC) in mice. METHODS: Colorectal liver metastases (CRLM) xenograft models were established by injecting tumor cells (LoVo, HT29 and HCT116) into spleen of mice, tumor-bearing xenograft models were established by subcutaneously injecting tumor cells in the right left flank of mice. Wound healing assays were performed to examine the ability of cell migration in vitro. 18F-FMISO uptake in CRC cell lines was measured by cellular uptake assay. 18F-FMISO-based micro-PET imaging of CRLM and tumor-bearing mice was performed and quantified by tumor-to-liver SUVmax ratio. The correlation between the 18F-FMISO SUVmax ratio, liver metastases number, hypoxia-induced factor 1α (HIF-1α) and serum starvation-induced glucose transporter 1 (GLUT-1) was evaluated using Pearson correlation analysis. RESULTS: Compared with HT29 and HCT116, LoVo-CRLM mice had significantly higher liver metastases ratio and shorter median survival time. LoVo cells exhibited stronger migration capacity and higher radiotracer uptake compared with HT29 and HCT116 in in vitro. Moreover, 18F-FMISO SUVmax ratio was significantly higher in both LoVo-CRLM model and LoVo-bearing tumor model compared to models established using HT29 and HCT116. In addition, Pearson correlation analysis revealed a significant correlation between 18F-FMISO SUVmax ratio of CRLM mice and number of liver metastases larger than 0.5 cm, as well as between 18F-FMISO SUVmax ratio and HIF-1α or GLUT-1 expression in tumor-bearing tissues. CONCLUSIONS: 18F-FMISO parameter of SUVmax ratio may provide useful tumor biological information in mice with CRLM, thus allowing for better prediction of CRLM and yielding useful radioactive markers for predicting liver metastasis potential in CRC.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Misonidazol/análogos & derivados , Tomografia por Emissão de Pósitrons/métodos , Intensificação de Imagem Radiográfica , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Invasividade Neoplásica/patologia , Distribuição Aleatória , Sensibilidade e Especificidade , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Phys Chem Chem Phys ; 20(39): 25467-25475, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30272075

RESUMO

MgxZn1-xO (ZMO) thin films with tunable Mg content were deposited by atomic layer deposition (ALD) on silicon substrates at 190 °C. The elemental and structural properties were acquired by X-ray photoelectron spectroscopy, transmission electron microscopy, atomic force microscopy and X-ray diffraction. Spectroscopic ellipsometry measurements were performed to reveal the evolution of the dielectric functions and critical points in the ZMO thin films by point-by-point fit in the photon energy range of 1.2-6.0 eV. The dependence of the dielectric functions on doping content is clearly demonstrated and physically explained. The critical point energies and the types of interband optical transitions were extracted from standard lineshape analysis of the second derivatives of the dielectric functions. The critical point features were discussed in terms of band structure modification and structural homogeneity arisen by introducing the Mg dopant into the films. Controlling these transitions by changing the doping content will be of practical significance in emerging ZMO-based thin-film photonic and optoelectronic devices.

7.
Hepatobiliary Pancreat Dis Int ; 17(2): 140-148, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29571649

RESUMO

BACKGROUND: Positron emission tomography (PET) is a noninvasive method to characterize different metabolic activities of tumors, providing information for staging, prognosis, and therapeutic response of patients with cancer. The aim of this study was to evaluate the feasibility of 18F-fludeoxyglucose (18F-FDG) and 3'-deoxy-3'-18F-fluorothymidine (18F-FLT) PET in predicting tumor biological characteristics of colorectal cancer liver metastasis. METHODS: The uptake rate of 18F-FDG and 18F-FLT in SW480 and SW620 cells was measured via an in vitro cell uptake assay. The region of interest was drawn over the tumor and liver to calculate the maximum standardized uptake value ratio (tumor/liver) from PET images in liver metastasis model. The correlation between tracer uptake in liver metastases and VEGF, Ki67 and CD44 expression was evaluated by linear regression. RESULTS: Compared to SW620 tumor-bearing mice, SW480 tumor-bearing mice presented a higher rate of liver metastases. The uptake rate of 18F-FDG in SW480 and SW620 cells was 6.07% ±â€¯1.19% and 2.82% ±â€¯0.15%, respectively (t = 4.69, P = 0.04); that of 18F-FLT was 24.81% ±â€¯0.45% and 15.57% ±â€¯0.66%, respectively (t = 19.99, P < 0.001). Micro-PET scan showed that all parameters of FLT were significantly higher in SW480 tumors than those in SW620 tumors. A moderate relationship was detected between metastases in the liver and 18F-FLT uptake in primary tumors (r = 0.73, P = 0.0019). 18F-FLT uptake was also positively correlated with the expression of CD44 in liver metastases (r = 0.81, P = 0.0049). CONCLUSIONS: The uptake of 18F-FLT in metastatic tumor reflects different biological behaviors of colon cancer cells. 18F-FLT can be used to evaluate the metastatic potential of colorectal cancer in nude mice.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/secundário , Neoplasias Colorretais/patologia , Didesoxinucleosídeos/administração & dosagem , Fluordesoxiglucose F18/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/administração & dosagem , Adenocarcinoma/metabolismo , Animais , Linhagem Celular Tumoral , Estudos de Viabilidade , Humanos , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Modelos Lineares , Neoplasias Hepáticas/metabolismo , Camundongos Nus , Valor Preditivo dos Testes , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Phys Chem Chem Phys ; 19(19): 12022-12031, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28443855

RESUMO

Centimeter-scale WS2 ultrathin films were synthesized on sapphire substrates, and they showed highly oriented crystallographic growth along the c axis. Afterwards, the as-grown samples were systematically characterized using various detection methods. Reliable values of the roughness layer thickness and the film thickness were extracted using both atomic force microscopy (AFM) and spectroscopic ellipsometry (SE), and identified using Raman spectroscopy as well. The expansion and tensile strain along the [001] direction were discovered using X-ray diffraction (XRD) measurements. Accurate dielectric functions of WS2 films were derived from the point-by-point fitting results. The critical points (CPs) of WS2, which have not been reported so far, are precisely extracted from the standard critical point (SCP) model. Their origins are uniquely assigned to different interband electronic transitions in the Brillouin zone, including some novel optical structures above 3 eV, which were not investigated in earlier studies. In this work, it is found that dielectric functions are thickness-dependent, while CPs have an opposite nature, and their intrinsic mechanisms are revealed. The as-obtained results can be expected to help people develop more extensive applications of WS2.

9.
Strahlenther Onkol ; 192(6): 394-402, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27215563

RESUMO

PURPOSE: The benefit of adjuvant chemotherapy (AC) in locoregionally advanced nasopharyngeal carcinoma (NPC) is controversial. This study compared concurrent chemoradiotherapy plus AC (CCRT/AC) with CCRT. METHODS: Pair-matched analysis based on eight clinicopathological features of 244 patients treated with platinum-based CCRT/AC or CCRT alone was performed. Survival outcomes were assessed using the Kaplan-Meier method and log-rank test. Toxicities and response rates were compared using Fisher's exact test. RESULTS: Four-year overall survival, progression-free survival, distant failure-free survival, and locoregional failure-free survival were 72 %, 61 %, 71 %, and 81 %, respectively, for the CCRT arm, compared to 74 % (hazard ratio, HR 0.89; 95 % confidence interval, CI 0.64-1.23; P = 0.474), 62 % (HR 0.91, 95 % CI 0.68-1.20, P = 0.489), 73 % (HR 0.84, 95 % CI 0.59-1.18, P = 0.316), and 84 % (HR 0.84, 95 % CI 0.52-1.24, P = 0.323), respectively, for the CCRT/AC arm. Cox multivariate regression analysis demonstrated AC was not an independent prognostic factor. Overall, there was a higher incidence of grade 3-4 toxicities in the CCRT/AC arm. The most common grade 3-4 adverse events in the CCRT/AC arm were vomiting (27 %), nausea (43 %), leukopenia/neutropenia (23 %), thrombocytopenia (8.8 %), and anemia (6.2 %). CONCLUSION: Addition of AC to CCRT increased toxicities but did not improve survival in locoregionally advanced NPC.


Assuntos
Quimiorradioterapia/mortalidade , Quimioterapia Adjuvante/mortalidade , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , China/epidemiologia , Feminino , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Prevalência , Lesões por Radiação/mortalidade , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
10.
Opt Lett ; 41(21): 4907-4910, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27805647

RESUMO

A new method for measuring the dielectric functions change with the thickness of nanometal thin films was proposed. To confirm the accuracy and reliability of the method, a nano-thin wedge-shaped gold (Au) film with continuously varied thicknesses was designed and prepared on K9 glass by direct-current-sputtering (DC-sputtering). The thicknesses and the dielectric functions in the wavelength range of 300-1100 nm of the nano-thin Au films were obtained by fitting the ellipsometric parameters with the Drude and critical points model. Results show that while the real part of the dielectric function (ϵ1) changes marginally with increasing film thickness, the imaginary part (ϵ2) decreases drastically with the film thickness, approaching a stable value when the film thickness increases up to about 42 nm. This method is particularly useful in the study of thickness-dependent optical properties of nano-thin film.

11.
Phys Chem Chem Phys ; 18(4): 3316-21, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26752103

RESUMO

The band gap and defect features of ultrathin ZrO2 films with varying thicknesses have been investigated by spectroscopic ellipsometry through the point-by-point data inversion method. The ε2-sprectra in the 3-6 eV range are extracted based on an optical model consisting of a Si substrate/effective ZrO2 film/air ambient structure where the effective ZrO2 film is a combination of interfacial layers and ZrO2. Evident widening of the band gap with a reducing size is observed when the effective ZrO2 films are below a critical thickness, somewhere between 8.80 nm and 17.13 nm. This is due to quantum-confinement and amorphous effects. Moreover, the sub-band-gap defects at interfacial layers and in bulk ZrO2 are identified and present strong thickness dependence as well. The interfacial defects at 3.26, 4.13, 4.43, and 4.77 eV mainly exist below the critical thickness and exhibit a significant suppression with increasing film thickness. The bulk defects at 4.15 eV and 4.46 eV dominate in ZrO2 films once they are over the critical thickness. The evolution of the band gap and defects is closely related to variance in the electronic structure of amorphous ZrO2. Our results may be helpful in understanding controversial problems concerning the size effect on ultrathin high-k oxide films and exploring the further miniaturization of electronic devices based on them.

12.
Nanomaterials (Basel) ; 13(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36770343

RESUMO

It is of great technological importance in the field of plasmonic color generation to establish and understand the relationship between optical responses and the reflectance of metallic nanoparticles. Previously, a series of indium nanoparticle ensembles were fabricated using electron beam evaporation and inspected using spectroscopic ellipsometry (SE). The multi-oscillator Lorentz-Drude model demonstrated the optical responses of indium nanoparticles with different sizes and size distributions. The reflectance spectra and colorimetry characteristics of indium nanoparticles with unimodal and bimodal size distributions were interpreted based on the SE analysis. The trends of reflectance spectra were explained by the transfer matrix method. The effects of optical constants n and k of indium on the reflectance were demonstrated by mapping the reflectance contour lines on the n-k plane. Using oscillator decomposition, the influence of different electron behaviors in various indium structures on the reflectance spectra was revealed intuitively. The contribution of each oscillator on the colorimetry characteristics, including hue, lightness and saturation, were determined and discussed from the reflectance spectral analysis.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3253-7, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23427546

RESUMO

The microstructure and fracture morphology of carbon coatings were investigated by means of Raman spectrometer and scanning electron microscopy (SEM), which were prepared by chemical vapor deposition (CVD) on the surface of SiC fiber with C2 H2 + H2 and C2 H2 +C3 H8 + Ar as the reactants. The results show that the spectra of the carbon coating contain characteristic D, D" and G peaks around 1 350, 1 400-1 500 and 1 600 cm(-1) respectively, indicating a disordered-graphite structure with a small amount of amorphous carbon. The size of microcrystallite increased with the increase in temperature, and the degree of order, together with the uniformity in the carbon coating was improved simultaneously. It was observed on the fracture surface that coatings prepared by C2 H2 + H2 are flat and dense, whereas those prepared by C2 H2 + C3 H8 + Ar exhibit a flexural lamellar structure, which should be attributed to the relatively low degree of order and the non-uniformity in the microstructure.

14.
Opt Express ; 19(14): 12969-77, 2011 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-21747448

RESUMO

A path-folded infrared image spectrometer with five sub-gratings and five linear-array detectors was applied to a broadband optical monitoring (BOM) system for thin film deposition. Through in situ BOM, we can simultaneously acquire the thickness and refractive index of each layer in real time by fitting the measured spectra, and modify the deposition parameters during deposition process according to the fitting results. An effective data processing method was proposed and applied in the BOM process, and it shortened the data processing time and improved the monitoring efficiency greatly. For demonstration, a narrow band-pass filter (NBF) at 1540 nm with ~10 nm full width at half-maximum (FWHM) had been manufactured using the developed BOM system, and the results showed that this BOM method was satisfying for monitoring deposition of thin film devices.


Assuntos
Manufaturas/efeitos da radiação , Membranas Artificiais , Refratometria/instrumentação , Espectrofotometria Infravermelho/estatística & dados numéricos , Raios Infravermelhos
15.
Sci Rep ; 11(1): 1093, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441851

RESUMO

Unlike the single grating Czerny-Turner configuration spectrometers, a super-high spectral resolution optical spectrometer with zero coma aberration is first experimentally demonstrated by using a compound integrated diffraction grating module consisting of 44 high dispersion sub-gratings and a two-dimensional backside-illuminated charge-coupled device array photodetector. The demonstrated super-high resolution spectrometer gives 0.005 nm (5 pm) spectral resolution in ultra-violet range and 0.01 nm spectral resolution in the visible range, as well as a uniform efficiency of diffraction in a broad 200 nm to 1000 nm wavelength region. Our new zero-off-axis spectrometer configuration has the unique merit that enables it to be used for a wide range of spectral sensing and measurement applications.

16.
Nanoscale ; 12(3): 1958-1966, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31909408

RESUMO

Monolayer MoS2 is a direct bandgap semiconductor which is believed to be one of the most promising candidates for optoelectronic devices. Chemical vapor deposition (CVD) is the most popular method to synthesize monolayer MoS2 with a large area. However, many defects are always found in monolayer MoS2 grown by CVD, such as sulfur vacancies, which severely degrade the performance of devices. This work demonstrates a concise and effective method for direct growth of high quality monolayer MoS2 by using SiO2/Si substrates pretreated with sulfur vapor. The MoS2 monolayer obtained using this method shows about 20 times PL intensity enhancement and a much narrower PL peak width than that grown on untreated substrates. Detailed characterization studies reveal that MoS2 grown on sulfur vapor pretreated SiO2/Si substrates has a much lower density of sulfur vacancies. The synthesis of monolayer MoS2 with high optical quality and low defect concentration is critical for both fundamental physics studies and potential practical device applications in the atomically thin limit.

17.
Opt Express ; 17(10): 8641-50, 2009 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-19434197

RESUMO

A new type of ellipsometer using an integrated analyzer composed of 12 sub-analyzers with different azimuth angles was constructed and studied. By using a two-dimensional CCD array camera to measure the light intensity emerging in parallel from each sub-analyzer with the azimuth angles uniformly distributed in the range of about 180 degrees , the ellipsometric parameters were extracted within the data acquisition time less than 1 second. The ellipsometric parameters for the polished bulk Si sample were measured to show good agreement with the results measured by using another two ellipsometric methods. The new method having the merits of high speed and reliability in the optical data measurement can be potentially used in the fields where the in situ data acquisition with high precision is the key issue as required.

18.
Zhen Ci Yan Jiu ; 44(5): 323-8, 2019 May 25.
Artigo em Zh | MEDLINE | ID: mdl-31155863

RESUMO

OBJECTIVE: To observe the effect of acupuncture plus moxibustion on the synaptic ultrastructure and expression of synaptic skeleton related proteins in the prefrontal cortex (PFC) of heroin re-addicted rats, so as to reveal its mechanisms underlying improvement of heroin addiction. METHODS: Twenty-four Wister rats (half male and half female) were randomly divi-ded into normal control, model and acupuncture groups (n=8 in each group). The heroin re-addicted model was established by muscular injection of heroin into the hind limbs for 8 days (incremental 0.8-3.6 mg, once daily for 6 days, and twice daily for 2 days), followed by conventional breeding for 5 days (detoxification), the procedure (addition-detoxification) was repeated 3 cycles. For rats of the acupuncture group, "Baihui" (GV20) was needled with filiform needles which were retained for 30 min, and moxibustion was then applied to bilateral "Shenshu" (BL23) for 30 min. The treatment was conducted once daily during the deto-xification. On the 39th day of experiment, the bilateral prefrontal cortex tissues were sampled for examining the ultrastructure by using transmission electron microscope (TEM) after fixative solution immersion and for determining the expression of genes and proteins of activity-regulated cytoskeleton-associated protein (Arc), microtubule-asso-ciated protein-2 (MAP-2) and microtubule-associated protein Tau (Tau) with quantitative real-time PCR and Western blot, respectively. RESULTS: After modeling, the expression levels of Arc mRNA and protein were significantly up-regulated, and those of MAP-2 and Tau mRNA and proteins ob-viously down-regulated in the model group relevant to the normal control group (P<0.05). Following the intervention, the up-regulated Arc protein and mRNA and the down-regulated MAP-2 and Tau were obviously reversed relevant to the model group (P<0.05). Outcomes of TEM showed unclear pre- and post-membranes of the synapses, narrowing of the synaptic gap and non-uniform of the density of the thickened dense plaque after modeling, which was relatively milder in the acupuncture group. CONCLUSION: Acupuncture plus moxibustion can improve changes of synaptic ultrastructure in heroin re-addicted rats, which may be related to their effect in regulating the expression of some synaptic skeleton proteins and genes.


Assuntos
Terapia por Acupuntura , Moxibustão , Animais , Feminino , Heroína , Masculino , Córtex Pré-Frontal , Ratos
19.
Cancer Chemother Pharmacol ; 84(1): 155-161, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31087135

RESUMO

BACKGROUND: The objective of this study was to evaluate the efficacy and safety of gemcitabine plus cisplatin concurrent chemoradiotherapy (CCRT) in patients with nasopharyngeal carcinoma. METHOD: Patients with NPC were randomly assigned to the gemcitabine plus cisplatin (GP) group or fluorouracil plus cisplatin (PF) group. Primary end-point was disease-free survival (DFS); secondary endpoints: overall survival, distant metastasis-free survival (DMFS), locoregional relapse-free survival, and treatment-related adverse events. RESULTS: Seventy-six patients were prospectively enrolled and the median follow-up time was 41 months (9-61 months). Three-year DFS were similar between the GP and PF groups (73.7% vs. 60.5%, HR 0.66, 95% CI 0.30-1.44; P = 0.30). Distant metastasis was the most common failure form in PF compared with GP (P = 0.034). Three-year DMFS was significantly better in the GP group than PF group (89.5% vs. 71.1%, P = 0.045). Grade 3-4 gastrointestinal toxicities (vomiting and diarrhea) were significantly more common in the PF group; grade 3-4 neutropenia and thrombocytopenia were more common in the GP group. CONCLUSION: Gemcitabine plus cisplatin could be used as an alternative regimen in CCRT for nasopharyngeal carcinoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem , Gencitabina
20.
Sci Rep ; 8(1): 8894, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29891841

RESUMO

Oxidative stress is known to be associated with various age-related diseases. D-galactose (D-gal) has been considered a senescent model which induces oxidative stress response resulting in memory dysfunction. Pyrroloquinoline quinone (PQQ) is a redox cofactor which is found in various foods. In our previous study, we found that PQQ may be converted into a derivative by binding with amino acid, which is beneficial to several pathological processes. In this study, we found a beneficial glutamate mixture which may diminish neurotoxicity by oxidative stress in D-gal induced mouse. Our results showed that PQQ may influence the generation of proinflammatory mediators, including cytokines and prostaglandins during aging process. D-gal-induced mouse showed increased MDA and ROS levels, and decreased T-AOC activities in the hippocampus, these changes were reversed by PQQ supplementation. Furthermore, PQQ statistically enhanced Superoxide Dismutase SOD2 mRNA expression. PQQ could ameliorate the memory deficits and neurotoxicity induced by D-gal via binding with excess glutamate, which provide a link between glutamate-mediated neurotoxicity, inflammation and oxidative stress. In addition, PQQ reduced the up-regulated expression of p-Akt by D-gal and maintained the activity of GSK-3ß, resulting in a down-regulation of p-Tau level in hippocampus. PQQ modulated memory ability partly via Akt/GSK-3ß pathway.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Galactose/toxicidade , Ácido Glutâmico/toxicidade , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteína Oncogênica v-akt/metabolismo , Cofator PQQ/administração & dosagem , Transdução de Sinais , Animais , Disfunção Cognitiva/induzido quimicamente , Citosol/química , Hipocampo/patologia , Fatores Imunológicos/administração & dosagem , Camundongos , Quinonas/análise , Espécies Reativas de Oxigênio/análise , Superóxido Dismutase/análise
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