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1.
Sci Bull (Beijing) ; 69(4): 492-501, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38044194

RESUMO

The performance applications (e.g., photocatalysis) of zirconium (Zr) and hafnium (Hf) based complexes are greatly hindered by the limited development of their structures and the relatively inert metal reactivity. In this work, we constructed two ultrastable Zr/Hf-based clusters (Zr9-TC4A and Hf9-TC4A) using hydrophobic 4-tert-butylthiacalix[4]arene (H4TC4A) ligands, in which unsaturated coordinated sulfur (S) atoms on the TC4A4- ligand can generate strong metal-ligand synergy with nearby active metal Zr/Hf sites. As a result, these two functionalized H4TC4A ligands modified Zr/Hf-oxo clusters, as catalysts for the amine oxidation reaction, exhibited excellent catalytic activity, achieving very high substrate conversion (>99%) and product selectivity (>90%). Combining comparative experiments and theoretical calculations, we found that these Zr/Hf-based cluster catalysts accomplish efficient amine oxidation reactions through synergistic effect between metals and ligands: (i) The photocatalytic benzylamine (BA) oxidation reaction was achieved by the synergistic effect of the dual active sites, in which, the naked S sites on the TC4A4- ligand oxidize the BA by photogenerated hole and oxygen molecules are reduced by photogenerated electrons on the metal active sites; (ii) in the aniline oxidation reaction, aniline was adsorbed by the bare S sites on ligands to be closer to metal active sites and then oxidized by the oxygen-containing radicals activated by the metal sites, thus completing the catalytic reaction under the synergistic catalytic effect of the proximity metal-ligand. In this work, the Zr/Hf-based complexes applied in the oxidation of organic amines have been realized using active S atom-directed metal-ligand synergistic catalysis and have demonstrated very high reactivity.

2.
J Am Chem Soc ; 145(29): 16098-16108, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37428127

RESUMO

While the difference in catalytic reactivity between mono- and multimetallic sites is often attributed to more than just the number of active sites, still few catalyst model systems have been developed to explore more underlying causal factors. In this work, we have elaborately designed and constructed three stable calix[4]arene (C4A)-functionalized titanium-oxo compounds, Ti-C4A, Ti4-C4A, and Ti16-C4A, with well-defined crystal structures, increasing nuclearity, and tunable light absorption capacity and energy levels. Among them, Ti-C4A and Ti16-C4A can be taken as model catalysts to compare the differences in reactivity between mono- and multimetallic sites. Taking CO2 photoreduction as the basic catalytic reaction, both compounds can achieve CO2-to-HCOO- conversion with high selectivity (close to 100%). Moreover, the catalytic activity of multimetallic Ti16-C4A is up to 2265.5 µmol g-1 h-1, which is at least 12 times higher than that of monometallic Ti-C4A (180.0 µmol g-1 h-1), and is the best-performing crystalline cluster-based photocatalyst known to date. Catalytic characterization combined with density functional theory calculations shows that in addition to the advantage of having more metal active sites (for adsorption and activation of more CO2 molecules), Ti16-C4A can effectively reduce the activation energy required for the CO2 reduction reaction by completing the multiple electron-proton transfer process rapidly with synergistic metal-ligand catalysis, thus exhibiting superior catalytic performance to that of monometallic Ti-C4A. This work provides a crystalline catalyst model system to explore the potential factors underlying the difference in catalytic reactivity between mono- and multimetallic sites.

3.
Angew Chem Int Ed Engl ; 62(31): e202303606, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37277319

RESUMO

H2 O2 photosynthesis coupled with biomass valorization can not only maximize the energy utilization but also realize the production of value-added products. Here, a series of COFs (i.e. Cu3 -BT-COF, Cu3 -pT-COF and TFP-BT-COF) with regulated redox molecular junctions have been prepared to study H2 O2 photosynthesis coupled with furfuryl alcohol (FFA) photo-oxidation to furoic acid (FA). The FA generation efficiency of Cu3 -BT-COF was found to be 575 mM g-1 (conversion ≈100 % and selectivity >99 %) and the H2 O2 production rate can reach up to 187 000 µM g-1 , which is much higher than Cu3 -pT-COF, TFP-BT-COF and its monomers. As shown by theoretical calculations, the covalent coupling of the Cu cluster and the thiazole group can promote charge transfer, substrate activation and FFA dehydrogenation, thus boosting both the kinetics of H2 O2 production and FFA photo-oxidation to increase the efficiency. This is the first report about COFs for H2 O2 photosynthesis coupled with biomass valorization, which might facilitate the exploration of porous-crystalline catalysts in this field.

4.
Adv Sci (Weinh) ; 10(21): e2301261, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37127898

RESUMO

The efficient CO2 electroreduction into high-value products largely relies on the CO2 adsorption/activation or electron-transfer of electrocatalysts, thus site-specific functionalization methods that enable boosted related interactions of electrocatalysts are much desired. Here, an oriented coordination strategy is reported to introduce N-rich auxiliary (i.e., hexamethylenetetramine, HMTA) into metalloporphyrin metal organic frameworks (MOFs) to synthesize a series of site-specific functionalized electrocatalysts (HMTA@MOF-545-M, M = Fe, Co, and Ni) and they are successfully applied in light-assisted CO2 electroreduction. Noteworthy, thus-obtained HMTA@MOF-545-Co presents approximately two times enhanced CO2 adsorption-enthalpy and electrochemical active surface-area with largely decreased impedance-value after modification, resulting in almost twice higher CO2 electroreduction performance than its unmodified counterpart. Besides, its CO2 electroreduction performance can be further improved under light-illumination and displays superior FECO (≈100%), high CO generation rate (≈5.11 mol m-2  h-1 at -1.1 V) and energy efficiency (≈70% at -0.7 V). Theoretical calculations verify that the oriented coordination of HMTA can increase the charge density of active sites, almost doubly enhance the CO2 adsorption energy, and largely reduce the energy barrier of rate determining step for the boosted performance improvement. This work might promote the development of modifiable porous crystalline electrocatalysts in high-efficiency CO2 electroreduction.

5.
J Am Chem Soc ; 145(16): 8860-8870, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37070784

RESUMO

The selective photoisomerization or photocyclization of stilbene to achieve value upgrade is of great significance in industry applications, yet it remains a challenge to accomplish both of them through a one-pot photocatalysis strategy under mild conditions. Here, a sevenfold interpenetrating 3D covalent organic framework (TPDT-COF) has been synthesized through covalent coupling between N,N,N,N-tetrakis(4-aminophenyl)-1,4-benzenediamine (light absorption and free radical generation) and 5,5'-(2,1,3-benzothiadiazole-4,7-diyl)bis[2-thiophenecarboxaldehyde] (catalytic center). The thus-obtained sevenfold interpenetrating structure presents a functional pore channel with a tunable photocatalytic ability and specific pore confinement effect that can be applied for selective stilbene photoisomerization and photocyclization. Noteworthily, it enables photogeneration of cis-stilbene or phenanthrene with >99% selectivity by simply changing the gas atmosphere under mild conditions (Ar, SeleCis. > 99%, SelePhen. < 1% and O2, SeleCis. < 1%, and SelePhen. > 99%). Theoretical calculations prove that different gas atmospheres possess varying influences on the energy barriers of reaction intermediates, and the pore confinement effect plays a synergistically catalytic role, thus inducing different product generation. This study might facilitate the exploration of porous crystalline materials in selective photoisomerization and photocyclization.

6.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902384

RESUMO

Bone loss occurs in astronauts during long-term space flight, but the mechanisms are still unclear. We previously showed that advanced glycation end products (AGEs) were involved in microgravity-induced osteoporosis. Here, we investigated the improvement effects of blocking AGEs formation on microgravity-induced bone loss by using the AGEs formation inhibitor, irbesartan. To achieve this objective, we used a tail-suspended (TS) rat model to simulate microgravity and treated the TS rats with 50 mg/kg/day irbesartan, as well as the fluorochrome biomarkers injected into rats to label dynamic bone formation. To assess the accumulation of AGEs, pentosidine (PEN), non-enzymatic cross-links (NE-xLR), and fluorescent AGEs (fAGEs) were identified in the bone; 8-hydroxydeoxyguanosine (8-OHdG) was analyzed for the reactive oxygen species (ROS) level in the bone. Meanwhile, bone mechanical properties, bone microstructure, and dynamic bone histomorphometry were tested for bone quality assessment, and Osterix and TRAP were immunofluorescences stained for the activities of osteoblastic and osteoclastic cells. Results showed AGEs increased significantly and 8-OHdG expression in bone showed an upward trend in TS rat hindlimbs. The bone quality (bone microstructure and mechanical properties) and bone formation process (dynamic bone formation and osteoblastic cells activities) were inhibited after tail-suspension, and showed a correlation with AGEs, suggesting the elevated AGEs contributed to the disused bone loss. After being treated with irbesartan, the increased AGEs and 8-OHdG expression were significantly inhibited, suggesting irbesartan may reduce ROS to inhibit dicarbonyl compounds, thus suppressing AGEs production after tail-suspension. The inhibition of AGEs can partially alter the bone remodeling process and improve bone quality. Both AGEs accumulation and bone alterations almost occurred in trabecular bone but not in cortical bone, suggesting AGEs effects on bone remodeling under microgravity are dependent on the biological milieu.


Assuntos
Produtos Finais de Glicação Avançada , Osteoporose , Ratos , Animais , Irbesartana , Produtos Finais de Glicação Avançada/metabolismo , Espécies Reativas de Oxigênio , Osso e Ossos/metabolismo
7.
J Am Chem Soc ; 145(11): 6112-6122, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36883963

RESUMO

Rational design of crystalline catalysts with superior light absorption and charge transfer for efficient photoelectrocatalytic (PEC) reaction coupled with energy recovery remains a great challenge. In this work, we elaborately construct three stable titanium-oxo clusters (TOCs, Ti10Ac6, Ti10Fc8, and Ti12Fc2Ac4) modified with a monofunctionalized ligand (9-anthracenecarboxylic acid (Ac) or ferrocenecarboxylic acid (Fc)) and bifunctionalized ligands (Ac and Fc). They have tunable light-harvesting and charge transfer capacities and thus can serve as outstanding crystalline catalysts to achieve efficient PEC overall reaction, that is, the integration of anodic organic pollutant 4-chlorophenol (4-CP) degradation and cathodic wastewater-to-H2 conversion. These TOCs can all exhibit very high PEC activity and degradation efficiency of 4-CP. Especially, Ti12Fc2Ac4 decorated with bifunctionalized ligands exhibits better PEC degradation efficiency (over 99%) and H2 generation than Ti10Ac6 and Ti10Fc8 modified with a monofunctionalized ligand. The study of the 4-CP degradation pathway and mechanism revealed that such better PEC performance of Ti12Fc2Ac4 is probably due to its stronger interactions with the 4-CP molecule and better •OH radical production. This work not only presents the effective combination of organic pollutant degradation and simultaneously H2 evolution reaction using crystalline coordination clusters as both anodic and cathodic catalyst but also develops a new PEC application for crystalline coordination compounds.

8.
Angew Chem Int Ed Engl ; 62(9): e202218868, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36581593

RESUMO

The full reaction photosynthesis of H2 O2 that can combine water-oxidation and oxygen-reduction without sacrificial agents is highly demanded to maximize the light-utilization and overcome the complex reaction-process of anthraquinone-oxidation. Here, a kind of oxidation-reduction molecular junction covalent-organic-framework (TTF-BT-COF) has been synthesized through the covalent-coupling of tetrathiafulvalene (photo-oxidation site) and benzothiazole (photo-reduction site), which presents visible-light-adsorption region, effective electron-hole separation-efficiency and photo-redox sites that enables full reaction generation of H2 O2 . Specifically, a record-high yield (TTF-BT-COF, ≈276 000 µM h-1 g-1 ) for H2 O2 photosynthesis without sacrificial agents has been achieved among porous crystalline photocatalysts. This is the first work that can design oxidation-reduction molecular junction COFs for full reaction photosynthesis of H2 O2 , which might extend the scope of COFs in H2 O2 production.

9.
Angew Chem Int Ed Engl ; 61(50): e202212162, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36229417

RESUMO

Strategy that can design powerful photothermal-catalysts to achieve photothermal-effect assisted coupling-catalysis is much desired for the improvement of energy conversion efficiency and redox product value in CO2 electroreduction system. Herein, a kind of bifunctional viologen-containing covalent organic framework (Ni-2CBpy2+ -COF) has been prepared and successfully applied in photothermal-assisted co-electrolysis of CO2 and methanol. Specifically, the FECO (cathode) and FEHCOOH (anode) for Ni-2CBpy2+ -COF can reach up to ≈100 % at 1.9 V with ≈31.5 % saved overall electricity-consumption when the anodic oxygen evolution reaction (OER) is replaced by methanol oxidation. The superior performance could be attributed to the cyclic diquats in Ni-2CBpy2+ -COF that enhance the photothermal effect (ΔT=49.1 °C) to accelerate faster charge transfer between catalyst and immediate species as well as higher selectivity towards desired products as revealed by DFT calculations and characterizations.

10.
Small ; 18(48): e2205444, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36284496

RESUMO

Metal-oxo clusters have emerged as advanced proton conductors with well-defined and tunable structures. Nevertheless, the exploitation of metal-oxo clusters with high and stable proton conductivity over a relatively wide temperature range still remains a great challenge. Herein, three sulfate groups decorated zirconium-oxo clusters (Zr6 , Zr18 , and Zr70 ) as proton conductors are reported, which exhibit ultrahigh bulk proton conductivities of 1.71 × 10-1 , 2.01 × 10-2 , and 3.73 × 10-2  S cm-1 under 70 °C and 98% relative humidity (RH), respectively. Remarkably, Zr6 and Zr70 with multiple sulfate groups as proton hopping sites show ultralow activation energies of 0.22 and 0.18 eV, respectively, and stable bulk conductivities of >10-2  S cm-1 between 30 and 70 °C at 98% RH. Moreover, a time-dependent proton conductivity test reveals that the best performing Zr6 can maintain high proton conductivity up to 15 h with negligible loss at 70 °C and 98% RH, representing one of the best crystalline cluster-based proton conducting materials.

11.
J Am Chem Soc ; 144(40): 18586-18594, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36191239

RESUMO

Structural exploration and functional application of thorium clusters are still very rare on account of their difficult synthesis caused by the susceptible hydrolysis of thorium element. In this work, we elaborately designed and constructed four stable thorium clusters modified with different functionalized capping ligands, Th6-MA, Th6-BEN, Th6-C8A, and Th6-Fcc, which possessed nearly the same hexanuclear thorium-oxo core but different capabilities in light absorption and charge separation. Consequently, for the first time, these new thorium clusters were treated as model catalysts to systematically investigate the light-induced oxidative coupling reaction of benzylamine and thermodriven oxidation of aniline, achieving >90% product selectivity and approximately 100% conversion, respectively. Concurrently, we found that thorium clusters modified by switchable functional ligands can effectively modulate the selectivity and conversion of catalytic reaction products. Moreover, catalytic characterization and density functional theory calculations consistently indicated that these thorium clusters can activate O2/H2O2 to generate active intermediates O2·-/HOO· and then improved the conversion of amines efficiently. Significantly, this work represents the first report of stable thorium clusters applied to photo/thermotriggered catalytic reactions and puts forward a new design avenue for the construction of more efficient thorium cluster catalysts.

12.
Angew Chem Int Ed Engl ; 61(37): e202209289, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35851736

RESUMO

The selective photo-oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is important due to its substitute-role in polyester-fabrication. Here, a titanium-cluster based metal-covalent organic framework nanosheet has been synthesized through the covalent-coupling between Ti6 -NH2 and benzotrithiophene tricarbaldehyde (BTT). The integration of them endows the nanosheet with a visible-light-adsorption region, effective electron-hole separation-efficiency and suitable photo-oxidation ability. Specifically, its photo-selectivity for HMF-to-FDCA can be >95 % with ≈100 % conversion, which is more than 2, 5, and 10 times higher than MOF-901 (43 %), Ti6 -NH2 (19 %) and under-darkness (9 %), respectively. Notably, an O2 -based mechanism is proposed and the vital roles of Ti6 -NH2 and BTT are verified by DFT calculations. This work might facilitate the exploration of porous-crystalline-catalysts for selective biomass-valorization.


Assuntos
Ácidos Dicarboxílicos , Titânio , Biomassa , Ácidos Dicarboxílicos/química , Furaldeído/química , Furanos/química , Porosidade , Titânio/química
13.
Angew Chem Int Ed Engl ; 61(34): e202207282, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35748491

RESUMO

Hybrid CO2 electroreduction (HCER) is recognized as an important strategy to improve the total value of redox products and energy conversion efficiency. In this work, a coordination catalyst model system (Ni8 -TET with active oxidation sites, Ni-TPP with active reduction sites and PCN-601 with redox-active sites) for HCER was established for the first time. Especially, PCN-601 can complete both anodic methanol oxidation and cathodic CO2 reduction with FEHCOOH and FECO over 90 %. The performance can be further improved with light irradiation (FE nearly 100 %). DFT calculations reveal that the transfer of electrons from NiII 8 clusters to metalloporphyrins under electric fields results in the raised oxidizability of Ni8 clusters and the raised reducibility of metalloporphyrin, which then improves the electrocatalytic performance. This work serves as a well-defined model system and puts forward a new design idea for establishing efficient catalysts for hybrid CO2 electroreduction.

14.
Biochem Biophys Res Commun ; 568: 151-157, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217013

RESUMO

Osteocytes are extremely sensitive to mechanical loading and govern bone remodeling process. Advanced glycation end products (AGEs) have the capacity to induce osteocyte apoptosis. In order to investigate the effects of AGEs on the mechanosensitivity of osteocytes, the osteocytic-like cells (MLO-Y4) were treated with low (50 µg/ml) and high (400 µg/ml) concentrations of AGEs for 1day and exposed to 15 dyne/cm2 of fluid shear stress. Then the F-actin cytoskeleton, prostaglandin E2(PGE2), Nitric oxide (NO), the Wnt/ß-catenin signaling pathway activity mRNA expressions were detected for osteocytes mechanical response changes; osteocalcin (OCN) and receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin (OPG) were detected for the regulation on bone remodeling function of osteocytes. The results showed that AGEs accumulation inhibited the sense of osteocytes to external mechincal loading, promoted shear-induced NO and PGE2 release, suppressed the mechanosensitivity of Wnt/ß-catenin signaling pathway, and furthermore promoted OCN and RANKL/OPG mRNA expressions. These indicated AGEs had an adverse impact on the mechanosensitivity of osteocytes, and led to a negative effect on their regulation of bone remodeling process under mechanical stimulation. This work provides a new perspective to interpret the alteration mechanism of osteocytes mechanosensitivity and provides a novel clue for exploring the mechanism of osteoporosis.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Osteócitos/metabolismo , Animais , Fenômenos Biomecânicos , Linhagem Celular , Camundongos , Osteócitos/citologia , Estresse Mecânico
15.
Opt Express ; 28(25): 37249-37264, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33379563

RESUMO

For the ill-posed inverse problem of LII-based nanoparticle size measurement, recovered primary particle size distribution (PPSD) is sensitive to the uncertainty of LII model parameters. In the absence of reliable prior knowledge, the thermal accommodation coefficient (TAC) and fractal-dependent shielding factor are often required to be inferred simultaneously with the PPSD. In the simplified LII model for low fluence regime, TAC and fractal-dependent shielding factor are combined to define a new fractal-dependent TAC. The present study theoretically verified the feasibility of inferring PPSD and fractal-dependent TAC from the normalized LII signals. Moreover, the inversion is independent of prior knowledge of most full LII model parameters, which is attributed to low laser fluence, normalized signal, and fractal-dependent TAC.

16.
Opt Express ; 28(14): 20609-20623, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32680117

RESUMO

Nowadays, the requirement for achieving dynamic radiative cooling is more and more intense, so a cooling system is proposed and developed to meet the demand in this paper. This cooling system is composed of a filter and a periodic trapezoidal VO2-Ge multilayer absorber (VGMA). The filter on the top enables the VGMA to reflect most of the solar irradiation at daytime and the absorptance or emittance of the VGMA is very different in the spectrum band of 8-13 µm for insulating and metallic VO2 due to the phase transition characteristic of VO2. With this cooling system, close-to-zero absorptance in the range of 0.3-2.5 µm and high (low) absorptance from 8 to 13 µm are achieved for metallic (insulating) VO2. Based on changing the temperature and absorptivity or emissivity simultaneously, radiative heat can be transferred dynamically to the outer space. When VO2 is in the insulating phase, the absorption mechanism of the absorber is magnetic resonance and surface plasmon polariton resonance, and broadband high absorptivity is achieved by exciting slowlight waveguide mode at broadband wavelengths when VO2 is in metallic phase. The spectral absorptance characteristics of the absorber in the two phase states are investigated as a function of the layer number and the incident angle of the electromagnetic waves. The results show that the absorber designed is insensitive to the incident angle. Moreover, the net cooling power of the VGMA of metallic VO2 is instantly 4 times more than that of insulating VO2 once the phase change temperature is reached. This work will be beneficial to the advancement of dynamic radiative cooling.

17.
J Ultrasound Med ; 38(10): 2611-2619, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30697783

RESUMO

OBJECTIVES: The aim of this study was to compare the differences between the ablation region and hyperechoic zones in microwave and radio frequency ablation of different tissues. METHODS: Microwave and radio frequency ablation were performed on fresh porcine muscle and liver with different power levels for 90 seconds. These 2 ablation methods were then performed on rabbit liver in vivo using 20 W for 60 seconds. The volumes of the ablation and hyperechoic zones were compared following different ablation methods. RESULTS: The ablation zones were significantly greater than the hyperechoic zones (P < .05) with the same power and duration when using 2 ablation methods. The differences of the ablation and hyperechoic zones between muscle and liver tissues were significantly different (P < .05). The difference values of the ablation and hyperechoic zones were also significantly different (P < .05) using 2 ablation methods. CONCLUSIONS: The hyperechoic zone may have underestimated the extent of ablation using a specified ablation time. In the same tissue, the hyperechoic zone could more accurately estimate the ablation zones using microwave ablation.


Assuntos
Técnicas de Ablação/métodos , Fígado/cirurgia , Músculo Esquelético/cirurgia , Animais , Ablação por Cateter/métodos , Micro-Ondas , Suínos
18.
Oncotarget ; 8(37): 61215-61225, 2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-28977858

RESUMO

In this study, hMex-3A was selected from TCGA database as a research object to observe the effects of small interfering RNA (siRNA) targeting hMex-3A on the biological activities of human bladder cancer and explore its mechanism for the first time. In this study, there were 2 groups including negative control group and hMex-3A-siRNA-transfected cells group for 5637 and T24 cell lines, respectively. After bladder cancer cells were transfected with the interference RNA sequence, proliferation of transfected cells were assessed by Celigo Cell Counting, and apoptosis were detected by flow cytometry. The knockdown rate of hMex-3A was 74% in 5637 cells and 68% in T24 cells after RNA interference. In addition, Celigo Cell Counting indicated that cell viability was significantly lower in hMex-3A-siRNA-transfected cells group (2196/well) than in negative control group (6777/well) (P < 0.05), but T24 cells did not show statistical significance between hMex-3A-siRNA-transfected cells group (5799/well) and negative control group (7899/well) (P >0.05). Flow cytometer showed that apoptosis was the highest and cells were significantly blocked after cells were transfected in hMex-3A-siRNA-transfected cells group in 5 days later (P < 0.05). Mex-3A protein was detected in bladder carcinoma sections with a mean staining intensity of 7.06±2.60. Mex-3A protein expression was significantly higher in cancerous tissue than in para-cancerous tissue (P <0.05). Our study suggested that siRNA targeting hMex-3A could markedly inhibit cell proliferation and promote apoptosis in 5637 cells. These might have significant implications to bladder carcinogenesis and serve as a potential target for the treatment of bladder cancer.

19.
Oncotarget ; 8(33): 54764-54774, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28903380

RESUMO

OBJECTIVE: Bladder urothelial carcinoma is a common tumor in humans and a multifactorial disease. The gene mex3a is associated with tumor formation and may promote cell proliferation and migration. Therefore, this study aimed to determine the relationship between mex3a and bladder urothelial carcinoma. METHODS: The clinical and RNA sequencing expression data in patients with bladder urothelial carcinoma were downloaded from the The Cancer Genome Atlas data portal. A total of 412 bladder urothelial carcinoma samples were available in the database, for which the clinical information was acquired, of which 412 are RNA sequencing samples with a total of 19 paired samples. Univariate and multivariate Cox analyses and univariate logistic regression analysis were conducted using the software SPSS version 22.0 and P<0.05 was considered statistically significant. RESULTS: The results of the independent t-test of 19 paired samples indicated that the expression level of mex3a was significantly higher in tumor tissues compared with adjacent normal tissues. Mex3a expression as a categorical dependent variable was not associated with overall survival, and the overall survival of bladder urothelial carcinoma was associated with the group of age, cancer status, lymphatic vascular invasion, pathological stage, pathological size, and pathological lymph metastasis. The multivariable Cox model adjusted for the group of mex3a expression level, age, gender, tumor status, and pathological stage showed that only the age and cancer status groups were associated with the overall survival. CONCLUSION: Mex3a expression was not a poor prognostic factor of bladder urothelial carcinoma. Moreover, the expression levels of mex3a in the papillary type of bladder urothelial carcinoma were higher than those of the non-papillary type.

20.
Opt Express ; 24(21): 24297-24312, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27828161

RESUMO

Sequential quadratic programming (SQP) is used as an optimization algorithm to reconstruct the optical parameters based on the time-domain radiative transfer equation (TD-RTE). Numerous time-resolved measurement signals are obtained using the TD-RTE as forward model. For a high computational efficiency, the gradient of objective function is calculated using an adjoint equation technique. SQP algorithm is employed to solve the inverse problem and the regularization term based on the generalized Gaussian Markov random field (GGMRF) model is used to overcome the ill-posed problem. Simulated results show that the proposed reconstruction scheme performs efficiently and accurately.

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