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141.
Jin Young Kim Kyung Hwa Cho Bo Young Jeong Chang Gyo Park Hoi Young Lee 《Experimental & molecular medicine》2020,52(7):1152
Rab coupling protein (RCP) is upregulated in head and neck squamous cell carcinoma (HNSCC) and is correlated with the progression and survival of patients. However, the role of RCP in one of the aggressive types of HNSCC, oral squamous cell carcinoma (OSCC), remains elusive. In the present study, we identified the important role of Zeb1 in RCP-induced OSCC epithelial-to-mesenchymal transition (EMT) and invasion. RCP induces Zeb1 expression, and silencing Zeb1 expression significantly inhibits RCP-induced OSCC invasion. In addition, Zeb1 upregulates MT1-MMP expression to promote OSCC EMT and invasion. Furthermore, we observed that the β1 integrin/EGFR/β-catenin signaling cascade mediates RCP-induced Zeb1 expression to promote OSCC invasion. Notably, we provide evidence that resveratrol (REV) strongly inhibits RCP-induced Zeb1 expression through blocking β1 integrin endosome recycling and EGFR activation, leading to suppression of RCP-induced OSCC invasion, demonstrating the important role of RCP in OSCC invasion and its reversion by REV. Collectively, the present study provides evidence for the first time that RCP aggravates OSCC invasion through increasing Zeb1 expression and subsequently upregulating MT1-MMP expression and that this process is reversed by REV, providing novel biomarkers and indicating the therapeutic potential of REV in OSCC.Subject terms: Oral cancer, Cell invasion 相似文献
142.
Vinayak Juvekar Chang Su Lim Dong Joon Lee Sang Jun Park Gyeong Ok Song Hyuk Kang Hwan Myung Kim 《Chemical science》2021,12(1):427
Two-photon photodynamic therapy (TP-PDT) is a promising approach for the treatment of cancer because of its better penetration depth and superior spatial selectivity. Here, we describe an azo group containing cyclized-cyanine derivatives (ACC1 and ACC2) as a two-photon activated, type I based photosensitizer (PS). These small-molecule and heavy atom-free organic dyes showed marked reactive oxygen species (ROS)-generating ability under physiological conditions, as well as fast loading ability into the cells and negligible dark toxicity. Live cell analyses with one- and two-photon microscopy revealed that these dyes showed higher ROS generation ability upon two-photon excitation than upon one-photon excitation via the type I process. The PSs have superior PDT properties compared to conventional Visudyne and 5-ALA under mild conditions. These characteristics allowed for precise PDT at the target region in mimic tumor spheroids, demonstrating that the developed TP PS could be useful in efficient PDT applications and in designing various PSs.Azo containing dyes as a two-photon selective and type I based photosensitizers (PSs) were developed that exhibit excellent photodynamic therapy properties under mild condition. 相似文献
143.
Kun Zhao Shuqi Zhuang Zhu Chang Haiyan Songm Liming Dai Pingang He Yuzhi Fang 《Electroanalysis》2007,19(10):1069-1074
A sensitive amperometric glucose biosensor based on platinum nanoparticles (PtNPs) combined aligned carbon nanotubes (ACNTs) electrode was investigated. PtNPs which can enhance the electrocatalytic activity of the electrode for electrooxidating hydrogen peroxide by enzymatic reaction were electrocrystallized on 4‐aminobenzene monolayer‐grafted ACNTs electrode by potential‐step method. These PtNPs combined ACNTs' (PtNPs/ACNTs) surfaces were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The highly dispersed PtNPs on ACNTs can be obtained. The enzyme electrode exhibits excellent response performance to glucose with linear range from 1×10?5–7×10?3 mol L?1 and fast response time within 5 s. Furthermore, this glucose biosensor also has good reproducibility. It is demonstrated that the PtNPs/ACNTs electrode with high electrocatalytic activity is a suitable basic electrode for preparing enzyme electrodes. 相似文献
144.
Chemodynamic therapy(CDT) is an emerging endogenous stimulation activated tumor treatment approach that exploiting iron-containing nanomedicine as catalyst to convert hydrogen peroxide(H_2O_2)into toxic hydroxyl radical(·OH) through Fenton reaction.Due to the unique characteristics(weak acidity and the high H_2O_2 level) of the tumor microenvironment,CDT has advantages of high selectivity and low side effect.However,as an important substrate of Fenton reaction,the endogenous H_2O_2 in tumor is still insufficient,which may be an important factor limiting the efficacy of CDT.In order to optimize CDT,various H_2O_2-generating nanomedicines that can promote the production of H_2O_2 in tumor have been designed and developed for enhanced CDT.In this review,we summarize recently developed nanomedicines based on catalytic enzymes,nanozymes,drugs,metal peroxides and bacteria.Finally,the challenges and possible development directions for further enhancing CDT are prospected. 相似文献
145.
Monomolecular films with well-defined structure were prepared by self-assembling of n-alkanoic acids on an evaporated silver surface. Here we report the structural studies of thin films of acids containing aromatic chromophores of varied size and polarity. Information regarding the packing, orientation and conformation of the structural units within the assembly were deduced from ellipsometric thickness measurement, polarized reflection absorption infrared spectra and wetting property measurement. Implications of results to the design of functional thin films are discussed. 相似文献
146.
Microwave synthesis,characterization and catalytic properties of titanium-incorporated ZSM-5 zeolite
Taihuan Jin Young Kyu Hwang Do-Young Hong Sung Hwa Jhung Jin-Soo Hwang San-Eon Park Young Ho Kim Jong-San Chang 《Research on Chemical Intermediates》2007,33(6):501-512
Titanium-incorporated ZSM-5 zeolites (Si/Al = 50–200 and Si/Ti = 70) were successfully synthesized in a one-step sol-gel process
under microwave irradiation. The characteristics of Ti-ZSM-5 zeolites were investigated using X-ray power diffraction, UV/Vis-DRS,
FT-IR spectroscopy and solid-state 27Al-NMR to monitor the physico-chemical properties. Simultaneously, the acidic properties were characterized by the NH3-TPD profile. The characterization results revealed that the Ti4+ and Al3+ ions were well incorporated into the framework of Ti-ZSM-5 zeolite. The prepared zeolite was moderately active but selective
in the dehydration of methanol to dimethyl ether. 相似文献
147.
[reaction: see text] A dendrimer with rotaxane-like characteristics has been assembled under thermodynamic control from complementary wedge-shaped precursors by slippage in CH(2)Cl(2). The driving force for the self-assembly process is the molecular recognition that exists as a result of [N(+)-H.O] and [C-H.O] hydrogen bonds between an NH(2)(+) center in one Fréchet-type benzyl ether wedge and a dibenzo[24]crown-8 unit that links the other two such wedges. 相似文献
148.
Synthesis and Crystal-Structure of Na2Mn3O7 Single crystals of Na2Mn3O7 have been grown hydrothermally applying high oxygen pressure (p = 2 kbar). The new compound cystallizes triclinic; space group P1 ; a = 6.636(6) Å, b = 6.854(6) Å, c = 7.548(6) Å, α = 105.76(6)°, β = 106.86(6)°, γ = 111.60(6)°; Z = 2. The crystal structure has been solved and refined to R = 7.9% and Rw = 6.2% (diffractometer data, 1044 independent reflexions). The crystal structure consists of Mn3O72? anions with manganese coordinated octahedrally by oxygen. These layered anions are hold together by Na+ ions (coordination numbers 5 and 6). 相似文献
149.
Hydrazinoethyl phosphoric monoester has been prepared by reacting hydrazinoethanol with polyphosphoric acid, and isolated as di-sodium salt. Sodium hydrazinoethyl phosphate reacts with phenylisothiocyanate (in H2O+ethanol) to yield mainly the derivative thiocarbamoylated at the substituted nitrogen atom. This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 3-amino-2-phenylimino-thiazolidine in 62% yield. Sodium hydrazinoethyl phosphate reacts with o-methoxycarbonylphenyl isothiocyanate (in H2O+dioxane) at the unsubstituted nitrogen atom to yield mainly the corresponding quinazoline derivative (IV, X = OPO3Na2). This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 2-o-carboxyphenylamino-dihydro-δ2-1, 3, 4-thiadiazine (Va) in 55% yield (hydrolysis of the lactamic function as well). Aminoethyl phosphorous monoester (colaminephosphorous acid) reacted with phenylisocyanate (in H20+dioxane) in slightly alkaline medium (one equivalent of NaOH) yields sodium N-phenylcarbamoylaminoethyl phosphite. Refluxed for 20 minutes in 1N NaOH, this carbamoyl derivative is not cyclized but only hydrolyzed to the open-chained N-phenyl-N′-hydroxyethylurea (VII). 相似文献
150.
Fang-Mo Chang Chen-Chia Huang Shin-Ming Shen Sun-I Chen 《Journal of Thermal Analysis and Calorimetry》1995,44(2):405-417
The effects of various burning rate catalysts on thermal decomposition of cured glycidyl azide polymer (GAP)-ammonium perchlorate (AP) propellants have been studied by means of thermal analysis and a modified vacuum stability test (MVST). Four types of iron-containing catalysts examined in this paper are catocene, ferrocenecarboxaldehyde (FCA), ferrocene, and ferric oxide. Results of differential thermal analysis (DTA) and thermogravimetric analysis (TG) revealed that the catalysts play an important role in the decomposition of both AP and GAP. The peak decomposition temperature (T m) of DTA curves and onset decomposition temperature (T o) of TG patterns considerably shifted to a lower temperature as the concentration of catalysts increased in the propellants. The endothermic temperature of AP, however, is unaffected by the presence of burning rate catalysts in all cases. The activation energy of decomposition of the propellants in range of 80 to 120°C is determined, based on the MVST results. 相似文献