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1.
Luminescence ; 38(10): 1720-1728, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37462124

RESUMO

Multistimuli-responsive fluorescent materials have garnered great research interest benefited from their practical applications. Two twisted-structure compounds containing tetraphenylethylene (TPE) as the aggregation-induced emission (AIE) group and a pyridine unit as the acid reaction site to obtain new multistimuli-responsive fluorescent compounds (namely, TPECNPy: TPECNPy-2 and TPECNPy-3) were successfully synthesized through a one-step Knoevenagel condensation reaction. The multiple-stimuli response process of TPECNPy was investigated by means of photoluminescence (PL) spectra and emission colour. The results showed that both TPECNPy compounds with excellent AIE abilities displayed reversible emission wavelength and colour changes in response to multiple external stimuli, including grinding-fuming by CH2 Cl2 or annealing and HCl-NH3 vapour fuming. More importantly, fluorescent nanofibre films were prepared by electrospinning a solution of TPECNPy mixed with cellulose acetate (CA), and these exhibited reversible acid-induced discolouration, even with only 1 wt% TPECNPy. The results of this study may inspire strategies for designing multistimuli-responsive materials and preparing fluorescent sensing nanofibre films.


Assuntos
Nanofibras , Fluorescência , Corantes Fluorescentes/química
2.
Molecules ; 28(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38138477

RESUMO

A tert-butyldiphenylsilyl-containing polyimide (PI-OSi) has been established as a colorimetric and ratiometric chemosensor for rapid detecting fluoride ions (F-). The UV-vis absorbance ratio value (A322/A288) of PI-OSi in a DMF solution displays a wide linear range change to F- concentrations with a detection limit (DL) value of 2.13 µM. Additionally, adding incremental amounts of F- to a DMF solution of PI-OSi shows an immediate color change to yellow and finally to green from colorless. More interestingly, the resulting PI-OSi plus F- system (PI-OSi·F) could detect trace water in DMF. The A292/A322 value of PI-OSi·F almost linearly increases with low water content, which suggests convenient quantitative sensing of trace water content in DMF. The DL value of PI-OSi·F for sensing water in DMF is determined to be 0.00149% (v/v). The solution color of PI-OSi·F returns to colorless when the water content increases, indicating that PI-OSi·F can conveniently estimate water content in DMF by naked-eye detection. The detection mechanisms confirmed by an 1H NMR study and a DFT calculation involve a F--induced desilylation reaction of PI-OSi to form phenolate anion followed by protonation with trace water. Finally, PI-OSi film was fabricated for the colorimetric detection of F- and water in CH3CN.

3.
J Phys Chem A ; 121(48): 9201-9210, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29096437

RESUMO

Both photoelectron spectroscopy (PES) data and PhotoElectron-PhotoIon-Coincidence (PEPICO) spectra obtained from a synchrotron facility have been used to examine the electronic structure and the dissociative ionization of halomethyl thiocyantes in the valence and shallow-core S 2p and Cl 2p regions. Two simple and closely related molecules, namely, CCl3SCN and CCl2FSCN, have been analyzed to assess the role of halogen substitution in the electronic properties of thiocyanates. The assignment of the He(I) photoelectron spectra has been achieved with the help of quantum chemical calculations at the outer-valence Green's function (OVGF) level of approximation. The first ionization energies observed at 10.55 and 10.78 eV for CCl3SCN and CCl2FSCN, respectively, are assigned to ionization processes from the sulfur lone pair orbital [n(S)]. When these molecules are compared with CX3SCN (X = H, Cl, F) species, a linear relationship between the vertical first ionization energy and electronegativity of CX3 group is observed. Irradiation of CCl3SCN and CCl2FSCN with photons in the valence energy regions leads to the formation of CCl2X+ and CClXSCN+ ions (X = Cl or F). Additionally, the achievement of the fragmentation patterns and the total ion yield spectra obtained from the PEPICO data in the S 2p and Cl 2p regions and several dissociation channels can be inferred for the core-excited species by using the triple coincidence PEPIPICO (PhotoElectron-PhotoIon-PhotoIon-Coincidence) spectra.

4.
Pak J Pharm Sci ; 30(3(Special)): 1125-1127, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28671094

RESUMO

To construct the pIRES2-MLAA34-HSP70 recombinant vector and express the MLAA34-HSP70 recombinant proteins in Escherichia coli (E. coli). The MLAA34 and the HSP70 genes were extracted from U937 cells by RT-PCR, and then we amplified the fusion gene MLAA34-HSP70 by SOE-PCR and inserted it into the pIRES2-EGFP vector to construct the pIRES2-MLAA34-HSP70 recombinant vector. We amplified the fusion gene MLAA34-HSP70 successfully and identified the correctness of pIRES2-MLAA34-HSP70 recombinant vector by PCR and restriction endonuclease. Moreover, the MLAA34-HSP70 recombinant proteins expressed in E. coli were consistent with the expected molecular weight. We constructed the pIRES2-MLAA34-HSP70 recombinant vector successfully and the MLAA34-HSP70 recombinant proteins were successfully expressed by the induction of IPTG.


Assuntos
Antígenos de Neoplasias/genética , Proteínas Reguladoras de Apoptose/genética , Expressão Gênica/genética , Linhagem Celular Tumoral , Escherichia coli/metabolismo , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Proteínas de Choque Térmico HSP70/genética , Humanos , Isopropiltiogalactosídeo/farmacologia , Plasmídeos , Reação em Cadeia da Polimerase , Proteínas Recombinantes de Fusão
5.
Bioorg Med Chem Lett ; 25(24): 5716-9, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26542965

RESUMO

4,4-Difluoro-3,5-bis(3,3-dimethyl-1-butenyl)-8-anthryl-4-bora-3a,4a-diaza-s-indacene (1), a symmetric fluorescent difluoroboron dipyrromethene dye, was produced in Knoevenagel reaction involving 4,4-difluoro-3,5-bis(methyl)-8-anthryl-4-bora-3a,4a-diaza-s-indacene (2) and pivaldehyde. Its crystal structure was determined by single crystal X-ray diffraction analysis, and the photophysical properties were investigated. The BODIPY 1 exhibits significant bathochromic shifts in both absorption and fluorescence spectrum compared with the BODIPY 2. In addition, the BODIPY 1 exhibited small energy gaps (2.11eV). The extensive π conjugation is responsible for their red-shifted emission. Cell imaging experiments demonstrated its potential application as a biological fluorescent probe due to its excellent imaging contrast.


Assuntos
Compostos de Boro/química , Butadienos/química , Corantes Fluorescentes/síntese química , Compostos de Boro/síntese química , Compostos de Boro/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Luz , Espectroscopia de Ressonância Magnética , Microscopia de Fluorescência , Conformação Molecular
6.
J Phys Chem A ; 118(31): 5950-60, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25019560

RESUMO

The valence electronic properties of S-ethyl flouromethanethioate (S-ethyl fluoromethsanethioate), FC(O)SCH2CH3, were investigated by means of He(I) photoelectron spectroscopy in conjunction with the analysis of the photofragmentation products determined by PEPICO (phtoelectron-photoion-coincidence) by using synchrotron radiation in the 11.1-21.6 eV photon energy range. The first band observed at 10.28 eV in the HeI photoelectron spectrum can be assigned with confidence to the ionization process from the HOMO [nπ(S) orbital], which is described as a lone pair formally localized on the sulfur atom, in agreement with quantum chemical calculations using the outer valence Green function method [OVGF/6-311++G (d,p)]. One of the most important fragmentation channels also observed in the valence region corresponds to the decarbonylation process yielding the [M-CO](·+) ion, which is clearly observed at m/z = 80. Moreover, S 2p and S 2s absorption edges have been examined by measuring the total ion yield spectra in the 160-240 eV region using variable synchrotron radiation. The dynamic of ionic fragmentation following the Auger electronic decay has been evaluated with the help of the PEPIPICO (photoion-photoion-photoelectron-coincidence spectra) technique.

7.
Chem Soc Rev ; 41(10): 3878-96, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22447121

RESUMO

Mechanofluorochromic materials, which are dependent on changes in physical molecular packing modes, have attracted considerable interest over the past ten years. In this review, recent progress in the area of pure organic mechanofluorochromism is summarized, and majority of the reported organic mechanofluorochromic systems are discussed, along with their derived structure-property relationships. The existence of a structural relationship between aggregation-induced emission compounds and mechanofluorochromism is recognized based on our recent results, which considered aggregation-induced emission compounds as a well of mechanofluorochromic materials. The established structure-property relationship will guide researchers in identifying and synthesizing more mechanofluorochromic materials.


Assuntos
Corantes Fluorescentes/química , Polímeros/química , Cristalização , Luz , Luminescência , Fenômenos Mecânicos , Modelos Moleculares
8.
J Phys Chem A ; 116(1): 231-41, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22098365

RESUMO

A combination of photoelectron spectroscopy and synchrotron based photoelectron photoion coincidence (PEPICO) spectra has been applied to investigate the electronic structure and the dissociative ionization of the CH(2)ClSCN molecule in the valence region. The PES is assigned with the electronic structure calculations at the outer-valence Green's function and symmetry adapted cluster/configuration interaction (SAC-CI) levels offer an explanation of our experimental results. Upon vacuum ultraviolet irradiation the low-lying radical cation, located at 10.39 eV is formed. The molecular ion is observed in the time-of-flight mass spectra, together with the CH(2)SCN(+) and CH(2)Cl(+) daughter ions. The total ion yield spectra have been measured in the S 2p and Cl 2p regions and several channels have been determined in dissociative photoionization events for the core-excited species. Thus, by using time-of-flight mass spectrometry and synchrotron radiation the relative abundances of the ionic fragments and their kinetic energy release values were obtained from both PEPICO and photoelectron photoion photoion coincidence spectra. Possible fragmentation processes are discussed and compared with that found for the related CH(3)SCN species.


Assuntos
Cloro/química , Enxofre/química , Tiocianatos/química , Cátions/química , Cinética , Espectrometria de Massas , Processos Fotoquímicos , Espectroscopia Fotoeletrônica , Síncrotrons , Raios Ultravioleta , Vácuo
9.
Artigo em Inglês | MEDLINE | ID: mdl-35833606

RESUMO

Metamaterials are artificially structured materials with unusual properties, such as negative Poisson's ratio, acoustic band gap, and energy absorption. However, metamaterials made of conventional materials lack tunability after fabrication. Thus, active metamaterials using magneto-mechanical actuation for untethered, fast, and reversible shape configurations are developed to tune the mechanical response and property of metamaterials. Although the magneto-mechanical metamaterials have shown promising capabilities in tunable mechanical stiffness, acoustic band gaps, and electromagnetic behaviors, the existing demonstrations rely on the forward design methods based on experience or simulations, by which the metamaterial properties are revealed only after the design. Considering the massive design space due to the material and structural programmability, a robust inverse design strategy is desired to create the magneto-mechanical metamaterials with preferred tunable properties. In this work, we develop an inverse design framework where a deep residual network replaces the conventional finite-element analysis for acceleration, realizing metamaterials with predetermined global strains under magnetic actuations. For validation, a direct-ink-writing printing method of the magnetic soft materials is adopted to fabricate the designed complex metamaterials. The deep learning-accelerated design framework opens avenues for the designs of magneto-mechanical metamaterials and other active metamaterials with target mechanical, acoustic, thermal, and electromagnetic properties.

10.
Biomater Adv ; 134: 112711, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35581069

RESUMO

The pH-responsive polymeric micelles (PMs) have been widely used as smart nano drug delivery systems to treat tumors. However, synchronously manipulating these PMs' self-assembly properties, drug release dynamics and tracing their pH-dependent intracellular fate remain challenges. Herein, we have first synthesized hyaluronic acid (HA) based glycopolypeptides modified by tetraphenylethylene (TPE) and a pH-sensitive doxorubicin (DOX) prodrug through Diels-Alder reaction, respectively. Then, the pH-responsive nanocomplexes (NCs) were prepared by coassembling the two obtained glycopolypeptides with different formulations. Controllable size within the range of 60-125 nm and morphologies like spherical, vesicular and oblate micelles can be easily accomplished by using this method; High drug encapsulating and loading efficiency can be easily realized and adjusted within a range of 86-97% and 7-25%, respectively; Acid sensitive drug release dynamics of these NCs are also tunable by using this way. Additionally, the programmed drug release induced by subtle pH variations can be extracellularly self-indicated by detecting the blue AIE changes of the TPE units through fluorescence resonance energy transfer (FRET) effect between DOX and TPE. More importantly, the dynamic pH-triggered DOX release can be easily traced inside the tumor cells by visualizing blue emission changes of the TPE through the FRET effect. In addition, both the size and the shape can affect the endocytic routes of the NCs; The HA coated NCs targeting the tumor cells can effectively inhibit the proliferation of the HeLa cells. This work can provide a new route to acquire the stimuli-responsive self-indicating PMs with the ability to adjust their self-assembly properties and their pH-triggered drug release dynamics, and even to simultaneously visualize the PMs' intracellular fate in a real-time.


Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Células HeLa , Humanos , Ácido Hialurônico/química , Concentração de Íons de Hidrogênio , Polímeros/química
11.
J Phys Chem A ; 115(21): 5307-18, 2011 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-21553925

RESUMO

A study of valence electronic properties of S-ethyl chlorothioformate (S-ethyl chloromethanethioate), ClC(O)SCH(2)CH(3), using HeI photoelectron spectra (PES) and synchrotron radiation is presented. Moreover, the photon impact excitation and dissociation dynamics of ClC(O)SCH(2)CH(3) excited at the S 2p and Cl 2p levels are elucidated by analyzing the total ion yield (TIY) spectra and time-of-flight mass spectra acquired in multicoincidence mode [photoelectron-photoion coincidence (PEPICO) and photoelectron-photoion-photoion coincidence (PEPIPICO)]. The HeI photoelectron spectrum is dominated by features associated with lone-pair electrons from the ClC(O)S- group, the HOMO at 9.84 eV being assigned to the n(π)(S) sulfur lone-pair orbital. Whereas the formation of C(2)H(5)(+) ion dominates the fragmentation in the valence energy region, the most abundant ion formed in both the S and Cl 2p energy ranges is C(2)H(3)(+). Comparison with related XC(O)SR (X = H, F, Cl and R = -CH(3), -C(2)H(5)) species reveals the impact of the alkyl chain on the photodissociation behavior of S-alkyl (halo)thioformates.

12.
ACS Appl Mater Interfaces ; 13(11): 12639-12648, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32897697

RESUMO

Magnetic soft materials (MSMs) have shown potential in soft robotics, actuators, metamaterials, and biomedical devices because they are capable of untethered, fast, and reversible shape reconfigurations as well as controllable dynamic motions under applied magnetic fields. Recently, magnetic shape memory polymers (M-SMPs) that incorporate hard magnetic particles in shape memory polymers demonstrated superior shape manipulation performance by realizing reprogrammable, untethered, fast, and reversible shape transformation and shape locking in one material system. In this work, we develop a multimaterial printing technology for the complex structural integration of MSMs and M-SMPs to explore their enhanced multimodal shape transformation and tunable properties. By cooperative thermal and magnetic actuation, we demonstrate multiple deformation modes with distinct shape configurations, which further enable active metamaterials with tunable physical properties such as sign-change Poisson's ratio. Because of the multiphysics response of the M-MSP/MSM metamaterials, one distinct feature is their capability of shifting between various global mechanical behaviors such as expansion, contraction, shear, and bending. We anticipate that the multimaterial printing technique opens new avenues for the fabrication of multifunctional magnetic materials.

13.
ACS Omega ; 6(47): 32327-32333, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34870052

RESUMO

Biodegradable mulch films are supposed to be a prospective substitute for poly(ethylene)-based mulch films in the field of sustainable agriculture. Among them, weeding mulch films play significant roles. However, the large-scale production of weeding mulch films through the traditional high-temperature film blowing process would often cause serious pollution due to the diffusion of herbicides in the surroundings. Herein, a green and facile coating approach is developed to produce biodegradable weeding mulch films. In our strategy, a herbicide was added into a poly(vinyl alcohol) aqueous solution with dopamine in it. After the subsequent low-temperature coating procedure on a biodegradable poly(butylene adipate-co-terephthalate)/poly(lactic acid) film, effective weeding mulch films were obtained. The morphology, structure, and mechanical property test results revealed the robustness and stability of the coating, and the pot experiments clearly demonstrated the effective weed suppression ability of the obtained weeding films. Evidently, this strategy to produce biodegradable weeding mulch films is green and facile, exhibiting great prospects in the large-scale production of weeding mulch films and other functional biodegradable mulch films.

14.
Front Chem ; 9: 727631, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422771

RESUMO

Fluorescent sensors that respond to environmental conditions (temperature, pressure, and pH) have attracted widespread attention in recent years. Generally, traditional solid-state fluorescent materials tend to suffer from aggregation-induced quenching (ACQ) and difficulty of film forming, limiting their extensive applications. Therefore, researchers are focusing more and more attention on fluorescent sensors with aggregation-induced emission (AIE) effects. Herein, the article reports an AIE molecule (TPEBZMZ) containing tetraphenylethylene (TPE) and benzimidazole fragments. The fluorescence properties of TPEBZMZ in solution and aggregation states have been investigated, and the luminescence performance and aggregation structures of solid-state TPEBZMZ after force and acid treatments have been explored. The results show obvious AIE and fluorescent sensing properties of TPEBZMZ, presenting force- and acid-induced discolorations. Moreover, the TPEBZMZ-based fluorescent nanofibrous film is fabricated by electrospinning the solution of TPEBZMZ blended with polylactic acid (PLA), which shows a good nanofiber film structure and exhibits reversible acid-induced discoloration property, even with only 0.5 wt% TPEBZMZ. This work provides a simple strategy to achieve stimulus-responsive fluorescent film.

15.
Neoplasia ; 23(6): 607-623, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34102455

RESUMO

Tumor metastasis is a leading cause of death in lung adenocarcinoma (LUAD) patients, but the molecular events that regulate metastasis have not been completely elucidated. STAMBP is a deubiquitinating enzyme of the Jab1/MPN metalloenzyme family that regulates the stability of substrates in cells by specifically removing ubiquitin molecules. We found that STAMBP expression was increased in the cytoplasm of tumor cells from LUAD patients. The STAMBP level was closely associated with tumor size, lymph node invasion and neoplasm disease stage. A high STAMBP level predicted poor overall survival and disease-free survival in LUAD patients. STAMBP overexpression promoted cell migration and invasion, whereas STAMBP knockdown attenuated these processes in LUAD cells after epidermal growth factor treatment. Mechanistically, increased STAMBP expression promoted the stabilization of Epidermal growth factor receptor (EGFR), whereas STAMBP knockdown induced the degradation of EGFR. STAMBP may deubiquitinate EGFR by localizing in early endosomes and increase EGFR membrane localization in LUAD cells. The overexpression of STAMBP triggered the activation of MAPK signaling after epidermal growth factor treatment. In contrast, this activation was attenuated in STAMBP knockdown cells. Small molecule inhibitors of EGFR and MAPK signaling pathway may block STAMBP-induced cell mobility and invasion as well as ERK activation in cells. Importantly, STAMBP knockdown suppressed LUAD tumor growth and metastasis by regulating the EGFR-mediated ERK activation in a xenograft mouse model. Our findings identified STAMBP as a novel potential target for LUAD therapy.


Assuntos
Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Ubiquitina Tiolesterase/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Modelos Animais de Doenças , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Endossomos/metabolismo , Receptores ErbB/metabolismo , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/farmacologia , Transporte Proteico , Transdução de Sinais/efeitos dos fármacos , Ubiquitina Tiolesterase/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Insect Sci ; 27(6): 1173-1185, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31829500

RESUMO

Peroxidasin plays a unique role in the formation and stability of extracellular matrix (ECM) in the animal kingdom; however, it was only characterized in Diptera, not in other insect orders. In this study peroxidasin (CsPxd) was first identified and characterized from Chilo suppressalis, a lepidopteran pest. CsPxd complementary DNA with a 4080 bp open reading frame encodes a peptide of 1359 amino acids; the derived amino acid sequence of CsPxd harbors the typical structural characteristics of peroxidasin family in heme-peroxidase superfamily, including the signal peptide at N-terminal, leucine-rich repeat domain, Ig-loop motifs and peroxidase domain, signifying the extracellular location of protein and the involvement in ECM formation. Eukaryotic expression reveals CsPxd protein displays peroxidase activity on H2 O2 , justifying the membership of peroxidase. Phyletic analysis shows the monophyletic evolution pattern of peroxidasin in insect phyle, and moreover only one peroxidasin is present in each species of insects, suggesting its evolutionary conservation on function. Peroxidasin messenger RNA is mainly expressed in egg and the final instar larvae stage. Injection of peroxidasin double-stranded RNA into the final instar larvae impacts the cuticle sclerotization during the metamorphosis from larvae to pupa, and eventually lead to lethality of larvae and pupa. These results suggest the presence of collagen crosslink in chorion and cuticle of insects, and indicate peroxidasin plays a role in the development of chorion and cuticle; furthermore peroxidasin might be the one of potential target genes for pest control using RNA interference.


Assuntos
Proteínas da Matriz Extracelular/genética , Proteínas de Insetos/genética , Mariposas/genética , Peroxidase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/metabolismo , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Mariposas/enzimologia , Mariposas/crescimento & desenvolvimento , Peroxidase/química , Peroxidase/metabolismo , Filogenia , Pupa/genética , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Peroxidasina
17.
J Cancer ; 11(22): 6675-6685, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33046988

RESUMO

Lung cancer is one of the most common malignant tumors in the world, with a high rate of malignancy and mortality. Seeking new biomarkers and potential drug targets is urgent for effective treatment of the disease. Deubiquitinase UCHL5/UCH37, as an important component of the 26S proteasome, plays critical roles in ubiquitinated substrate degradation. Although previous studies have shown that UCHL5 promotes tumorigenesis, its role in lung cancer remains largely unknown. In this study, we evaluated the expression and clinical significance of UCHL5 in non-small cell lung cancer (NSCLC). The results demonstrated that the UCHL5 expression level was significantly upregulated in NSCLC tissues compared with the adjacent noncancerous tissues. The level of UCHL5 was associated with tumor size, lymph node invasion, TNM stage and malignant tumor history in patients with lung adenocarcinoma (LUAD). Importantly, high UCHL5 expression predicted a poor overall survival (OS) and a poor disease-free survival (DFS) in patients with LUAD. Univariate regression analysis showed that tumor size, lymph node invasion, TNM stage and UCHL5 expression were associated with OS and DFS in patients with LUAD. The multivariate analysis indicated that the UCHL5 expression level was an independent prognostic factor for OS (HR=1.171, 95% CI=1.052-1.303) and DFS (HR=1.143, 95% CI=1.031-1.267) in these patients. UCHL5 knockdown in LUAD cells significantly inhibited cell proliferation and reduced the expression of key cell cycle proteins. These findings indicate that UCHL5 may serve as a potential prognostic marker and a new therapeutic target for patients with LUAD.

18.
J Cancer ; 11(10): 2962-2971, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32226511

RESUMO

PSMD14 is a 19S-proteasome-associated deubiquitinating enzyme that facilitates protein degradation by the 20S proteasome core particle. Although accumulating evidence indicates that PSMD14 has emerged as a critical oncogenic factor by promoting tumor growth, the expression and function of PSMD14 in non-small cell lung cancer (NSCLC) remain largely unknown. In this study, we assessed PSMD14 expression and correlated it with clinical-pathological features and patient survival in NSCLC. We also determined the roles of PSMD14 in the regulation of lung adenocarcinoma (LUAD) cell growth. The results showed that PSMD14 expression was significantly upregulated in human NSCLC tissues compared with adjacent non-cancerous tissues. The PSMD14 level was associated with tumor size, lymph node invasion, and TNM stage in LUAD patients. Importantly, high PSMD14 expression was associated with poor overall survival (OS) and disease-free survival (DFS) in LUAD patients. Further, knockdown of PSMD14 significantly inhibited cell growth and caused G1 arrest and cellular senescence by increasing p21 stability in LUAD cells. PSMD14 knockdown also promoted cell apoptosis by increasing cleaved caspase-3 levels in H1299 cells. PSMD14 may serve as a potential prognostic marker and therapeutic target for LUAD patients.

19.
J Phys Chem A ; 113(13): 3108-15, 2009 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-19265393

RESUMO

Acryloyl isocyanate CH(2)=CHC(O)NCO is quantitatively prepared by the metathesis reaction between CH(2)=CHC(O)Cl and AgNCO. Also, jointly with acryloyl chloride, their molecular and electronic structures have been investigated by photoionization mass spectroscopy (PIMS), HeI photoelectron spectroscopy (PES), and theoretical calculations. CH(2)=CHC(O)NCO was theoretically predicted to prefer the trans-cis (tc) conformation as the most stable conformer, with the C=O bond trans to the C=C bond and cis to the NCO moiety. IR and Raman spectra also suggest the presence of the trans-cis (tc) conformation only. Calculations of the cationic-radical form were carried out in order to compare their properties with those of the neutral molecules. It is worthwhile mentioning that both compounds retain planar structures after ionization. After structural optimizations, a theoretical study involving the calculation of the ionization energies using orbital valence Green's functional (OVGF) was performed. The ionization energies of different bands in the photoelectron spectrum are in good agreement with the calculated values from the OVGF method. The first vertical ionization energies of CH(2)=CHC(O)Cl and CH(2)=CHC(O)NCO are determined to be 10.97 and 10.68 eV, respectively. The HOMOs correspond to the ionization of electrons mainly localized on the pi(C=C) or the pi(NCO) orbitals: {4a''(pi(C=C))}(-1) and {5a''(pi(NCO))}(-1), respectively.


Assuntos
Acrilatos/química , Elétrons , Modelos Químicos , Processos Fotoquímicos , Cátions/química , Radicais Livres/química , Modelos Moleculares , Conformação Molecular , Espectrometria de Massas por Ionização por Electrospray , Análise Espectral , Vibração
20.
Materials (Basel) ; 12(5)2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30818794

RESUMO

In this study, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) methods were used to study the structure, the thermal degradation kinetics, and the thermogram of sweet potato starch, respectively. The thermal decomposition kinetics of sweet potato starch was examined within different heating rates in a nitrogen atmosphere. Different models of kinetic analysis were used to calculate the activation energies using the thermogravimetric data of the thermal degradation process. The activation energies got from Kissinger, Flynn⁻Wall⁻Ozawa, and Satava⁻Sesták models were 173.85, 174.87, and 174.34 kJ·mol-1, respectively. Thermogravimetry⁻Fourier transform infrared spectroscopy (TG-FTIR) analysis showed that the main pyrolysis products included water, carbon dioxide, and methane.

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