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1.
Phys Rev Lett ; 132(14): 143201, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38640361

RESUMO

We present a kinematically complete study on strong-field double ionization of H_{2} molecules in two-color bicircular laser fields. The releasing times of electrons and protons are recorded with the double-hand attoclock. We observe the relative emission angles of two electrons oscillate with the kinetic energy release of protons, indicating the internal concerted four-body fragmentation. Using a three-dimensional molecular semiclassical ensemble model, we have disentangled the attosecond correlated electron emission in H_{2} double ionization. This work reveals the strong electron-nuclear coupling in the molecular bond breaking and may open up a new approach to experimentally accessing the intramolecular electron and bond dynamics with bicircular fields.

2.
J Am Chem Soc ; 146(15): 10443-10450, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38530937

RESUMO

The Jahn-Teller (JT) distortion is one of the fundamental processes in molecules and condensed phase matters. For photoionized organic molecules with high symmetry, the JT effect leads to geometric instability in certain electron configurations and thus has a significant effect on the subsequent isomerization and proton migration processes. Utilizing the femtosecond pump-probe Coulomb explosion method, we probe the isomerization dynamics process of a monovalent cyclopropane cation (C3H6+) caused by proton migration and reveal the relationship between proton migration and JT distortion. We found that the C3H6+ cation evolves from the D3h symmetric equilateral triangle geometry either to the acute triangle via two elongated C-C bonds (JT1) or to the obtuse triangle via a single elongated C-C bond (JT2). The JT1 pathway does not involve proton migration, while the JT2 pathway drives proton migration and can be mapped into the indirect dissociation channel of Coulomb explosion. The time-resolved experiment indicates that the delay time between those two JT pathways can be as large as ∼600 fs. After the JT distortion, the cyclopropane cation undergoes a subsequent structural evolution, which brings a greater variety of dissociation channels.

3.
J Phys Chem Lett ; 15(9): 2369-2374, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393833

RESUMO

Ubiquitous ultrafast isomerization is paramount in photoexcited molecules, in which non-adiabatic coupling among multiple electronic states can occur. We use the pump-probe Coulomb explosion imaging method to study the isomerization of CH3Cl molecules. We find that the isomerization under our strong field pump-probe scheme proceeds along multiple pathways, which are encoded in several distinct branches of the time-resolved kinetic energy release spectra for the CH2++HCl+ Coulomb explosion channel. Apart from the isomerized dissociative pathway in neutral and cationic excited states, the pump laser can also induce coherent vibrational dynamics in two coupled intermediate states and set up the initial conditions for the two concurrently proceeding isomerization pathways. The isomerization of CH3Cl provides an intriguing example of a chemical reaction consisting of multiple pathways and non-adiabatic dynamics.

4.
J Environ Manage ; 351: 119841, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38109828

RESUMO

The combination of organic and heavy metal pollutants can be effectively and sustainably remediated using bioremediation, which is acknowledged as an environmentally friendly and economical approach. In this study, bacterial agent YH was used as the research object to explore its potential and mechanism for bioremediation of pyrene-heavy metal co-contaminated system. Under the optimal conditions (pH 7.0, temperature 35°C), it was observed that pyrene (PYR), Pb(II), and Cu(II) were effectively eliminated in liquid medium, with removal rates of 43.46%, 97.73% and 81.60%, respectively. The microscopic characterization (SEM/TEM-EDS, XPS, XRD and FTIR) results showed that Pb(II) and Cu(II) were eliminated by extracellular adsorption and intracellular accumulation of YH. Furthermore, the presence of resistance gene clusters (cop, pco, cus and pbr) plays an important role in the detoxification of Pb(II) and Cu(II) by strains YH. The degradation rate of PYR reached 72.51% in composite contaminated soil, which was 4.33 times that of the control group, suggesting that YH promoted the dissipation of pyrene. Simultaneously, the content of Cu, Pb and Cr in the form of F4 (residual state) increased by 25.17%, 6.34% and 36.88%, respectively, indicating a decrease in the bioavailability of heavy metals. Furthermore, YH reorganized the microbial community structure and enriched the abundance of hydrocarbon degradation pathways and enzyme-related functions. This study would provide an effective microbial agent and new insights for the remediation of soil and water contaminated with organic pollutants and heavy metals.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Chumbo , Poluentes do Solo/química , Metais Pesados/análise , Biodegradação Ambiental , Pirenos , Solo/química
5.
Am J Chin Med ; 51(2): 445-459, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891981

RESUMO

Dihydroartemisinin (DHA) has anticancer effects on multiple tumors, including those associated with breast cancer. This study aimed to investigate the mechanism causing DHA-reversing cisplatin (DDP) resistance in breast cancer. Relative mRNA and protein levels were tested using a qRT-PCR and western blot assay. Cell proliferation, viability, and apoptosis were evaluated using colony formation, MTT, and flow cytometry assays, respectively. Interaction of STAT3 and DDA1 was measured via a dual-luciferase reporter assay. The results showed that DDA1 and p-STAT3 levels were dramatically elevated in DDP-resistant cells. DHA treatment repressed proliferation and induced apoptosis of DDP-resistant cells by suppressing STAT3 phosphorylation; the inhibition ability was positively proportional to the DHA concentration. DDA1 knockdown inhibited cyclin expression, promoted G0/G1 phase arrest, restrained cell proliferation, and induced apoptosis of DDP-resistant cells. Furthermore, knockdown of STAT3 restrained proliferation and induced apoptosis and G0/G1 cell cycle arrest of DDP-resistant cells by targeting DDA1. DHA could restrain tumor proliferation of breast cancer via enhancing drug sensitivity of DDP-resistant cells through the STAT3/DDA1 signaling pathway.


Assuntos
Antineoplásicos , Neoplasias da Mama , MicroRNAs , Neoplasias Ovarianas , Feminino , Humanos , Cisplatino/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias Ovarianas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Transdução de Sinais/genética , Proliferação de Células , Apoptose/genética , MicroRNAs/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
6.
Mol Biotechnol ; 65(11): 1764-1776, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36780057

RESUMO

In this study, Skullcapflavone I and Skullcapflavone II molecules showed good inhibitory activities against α-glucosidase and sorbitol dehydrogenase enzymes with IC50 values of 102.66 ± 8.43 and 95.04 ± 11.52 nM for α-glucosidase and 38.42 ± 3.82 and 28.81 ± 3.26 µM for sorbitol dehydrogenase. The chemical activities of Skullcapflavone I and Skullcapflavone II against α-glucosidase and sorbitol dehydrogenase were assessed by conducting the molecular docking study. The anticancer activities of the compounds were examined against SW-626, SK-OV-3, OVCAR3, and Caov-3 cell lines. The chemical activities of Skullcapflavone I and Skullcapflavone II against some of the expressed surface receptor proteins (estrogen receptor, EGFR, androgen receptor, and GnRH receptor) in the mentioned cell lines were investigated using in silico calculations. Moreover, the activity of the compounds against RNA polymerase of SARS-COVE-2 was also assessed using the molecular modeling study. These compounds created strong contacts with the enzymes and receptors. The considerable binding affinity of the compounds to the enzymes and proteins showed their ability as inhibitors. Furthermore, even at modest dosages, these substances markedly reduced the viability of ovarian cancer cells. Additionally, the viability of ovarian cancer cells was significantly decreased by a 300 µM dosage of all compounds. Antiovarian cancer results of Skullcapflavone I on SK-OV-3, SW-626, OVCAR3, and Caov-3 were 63.14, 1.55, 19.42, and 52.04 µM, respectively. Also, cytotoxicity results of Skullcapflavone II on SK-OV-3, SW-626, OVCAR3, and Caov-3 were 5.18, 21.44, 33.87, and 72.66 µM, respectively.


Assuntos
COVID-19 , Neoplasias Ovarianas , Humanos , Feminino , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular , SARS-CoV-2 , Apoptose , alfa-Glucosidases , L-Iditol 2-Desidrogenase , RNA Polimerase Dependente de RNA
7.
Immunopharmacol Immunotoxicol ; 45(4): 443-454, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36605015

RESUMO

CONTEXT: Breast cancer (BC) is the most prevalent diagnosed tumor and the major reason for tumor-related death in females around the world. Isoliquiritin, a type of plant extract, has exhibited a probable inhibitory effect in a variety of cancers. However, the anti-tumor effect on BC is still unclear. OBJECTIVE: To reveal the effect and potential mechanism of Isoliquiritin on BC. MATERIALS AND METHODS: The cell viabilities were detected by CCK-8 assay. The levels of indicators of ferroptosis, oxidative stress, glycolysis, and inflammation were evaluated by commercial kits, flow cytometry, western blot, spectrophotometry, and ELISA assays. Mechanically, the expressions expression of the NF-κB pathway was determined by western blot. In vivo assay was also yielded on the BALB/c nude mice. RESULTS: Iso induced a concentration and time-dependent decrease of viability in both MDA-MB-231 and MCF-7 cells. Iso treatment significantly increased the levels of Fe2+, ROS, and MDA, and decreased the GSH level, and the relative protein expressions of GPX4 and xCT. Furthermore, Iso modulated oxidative stress, glycolysis, and inflammation through ferroptosis. In addition, Iso induced a concentration-dependent decrease in cell viability and a concentration-dependent increase in apoptosis rate in both MDA-MB-231/Dox and MCF-7/Dox cells. Iso notably counteracted the LPS-induced relative protein levels of p-p50/p50, p-p65/p65, and IκB, and the levels of ferroptosis, oxidative stress, glycolysis, and inflammation. The same results were also verified in vivo. CONCLUSION: Iso inhibited the NF-κB signaling to regulate ferroptosis and improved Dox-resistance in breast cancer.


Assuntos
Ferroptose , Neoplasias , Animais , Feminino , Camundongos , Doxorrubicina/efeitos adversos , Inflamação/metabolismo , Camundongos Nus , NF-kappa B/metabolismo , Resistencia a Medicamentos Antineoplásicos , Camundongos Endogâmicos BALB C
8.
Saudi J Gastroenterol ; 28(5): 369-377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35381832

RESUMO

Background: : NOP2 nucleolar protein plays a crucial role in early embryo development and cell proliferation. The role of NOP2 in human gastric adenocarcinoma has not been elucidated. In the present study, we aimed to examine the expression levels of NOP2 and dissected whether NOP2 expression was associated with aggressive clinicopathological outcomes of patients with gastric adenocarcinoma. Methods: : Clinicopathological analysis was performed in patients with gastric adenocarcinoma. Expression of NOP2 was tested by immunohistochemistry staining and quantitative RT-PCR. The prognostic role of NOP2 in gastric adenocarcinoma patients was assessed by univariate and multivariate analysis. The effect of NOP2 on cell proliferation was examined through cellular experiments and mice models. Results: : NOP2 expression was elevated in gastric adenocarcinoma tissues compared to normal gastric tissues. High expression of NOP2 was significantly correlated with tumor size, invasion depth, and lymph node metastasis. Moreover, patients with high NOP2 expression had poorer overall survival, and NOP2 was identified as an independent prognosis factor. Using the gastric adenocarcinoma cells, we found that NOP2 can promote tumor cell proliferation both in vitro and in vivo. Conclusions: : Overexpression of NOP2 significantly correlates with a poorer prognosis of gastric adenocarcinoma patients and suggested the potential of NOP2, which may serve as a novel prognostic biomarker in gastric adenocarcinoma.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Biomarcadores , Biomarcadores Tumorais/metabolismo , Humanos , Camundongos , Proteínas Nucleares/genética , Prognóstico , Neoplasias Gástricas/metabolismo , tRNA Metiltransferases
9.
Kaohsiung J Med Sci ; 37(7): 572-582, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33728753

RESUMO

Nobiletin is a polymethoxylated flavone present in citrus fruits, which has been reported to have inhibitory effects on tumorigenesis of cancers. However, the biological function of nobiletin in breast cancer (BC) is largely unknown. To investigate the effect of nobiletin on growth of BC cells, the cell viability of BC was measured by MTT assay. In addition, gene and protein expressions were detected by qRT-PCR and western blot, respectively. The apoptosis and pyroptosis of BC cells were tested by flow cytometry. Finally, the correlation between miR-200b and JAZF1 was detected by dual luciferase report. The data indicated that nobiletin inhibited the proliferation of BC cells in a dose-dependent manner. Moreover, miR-200b mimics-induced pyroptosis of BC cells was further increased by nobiletin. Meanwhile, JAZF1 was found to be the target of miR-200b. Moreover, nobiletin induced apoptosis and pyroptosis of BC cells via miR-200b/JAZF1/NF-κB axis. In conclusion, nobiletin inhibited the tumorigenesis of BC via regulation of miR-200b/JAZF1 axis. Thus, nobiletin might serve as a new agent for the treatment of BC.


Assuntos
Neoplasias da Mama/patologia , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/metabolismo , Flavonas/farmacologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Piroptose , Apoptose , Carcinogênese , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Sobrevivência Celular , Proteínas de Ligação a DNA/genética , Feminino , Citometria de Fluxo , Humanos , Células MCF-7 , MicroRNAs/genética , NF-kappa B/metabolismo , Transdução de Sinais , Sais de Tetrazólio/química , Tiazóis/química , Transfecção
10.
Sheng Wu Gong Cheng Xue Bao ; 36(9): 1929-1938, 2020 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-33164468

RESUMO

ω-transaminase (ω-TA) is the most promising biocatalyst for chiral amine synthesis. However, most wild-type ω-TAs cannot be applied in industry directly due to their low stability and unfavorable reaction equilibrium. In order to discover a novel ω-TA for industrial application, we designed a procedure of adaptive selection, including the screening of substrates, protein sequences and clones, enzyme activity, and product conversion and characterization, as well as trouble-shooting of each step. Through this procedure, we screened a novel ω-TA, ATA-W12 of Caulobacter sp. from a soil metagenome. The strain could convert 20 mmol/L 1-Boc-3-pyrrolidinone and 20 mmol/L 1-Boc-3-piperidone with 85.84% and 67.42% conversion rate, respectively, in a 1-mL scale with isopropylamine (IPA) as amine donor. ATA-W12 maintained 100% activity at 40 °C for 168 h, and its optimal reaction condition is at pH 8.5 and 40 °C. These excellent properties benefit the application of IPA as an ideal amino donor in industry. We scaled up the production of (S)-(+)-1-boc-3-aminopiperidine up to 50 mL (100 g/L) scale with this novel biocatalyst for its further industrial application.


Assuntos
Aminas , Transaminases , Sequência de Aminoácidos , Transaminases/genética
11.
BMC Microbiol ; 20(1): 190, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611380

RESUMO

BACKGROUND: Cow manure is not only an agricultural waste, but also an organic fertilizer resource. The application of organic fertilizer is a feasible practice to mitigate the soil degradation caused by overuse of chemical fertilizers, which can affect the bacterial diversity and community composition in soils. However, to our knowledge, the information about the soil bacterial diversity and composition in tea plantation applied with cow manure fertilization was limited. In this study, we performed one field trial to research the response of the soil bacterial community to cow manure fertilization compared with urea fertilization using the high-throughput sequencing technique of 16S rRNA genes, and analyzed the relationship between the soil bacterial community and soil characteristics during different tea-picking seasons using the Spearman's rank correlation analysis. RESULTS: The results showed that the soil bacterial communities were dominated by Proteobacteria, Bacteroidetes, Acidobacteria and Actinobacteria across all tea-picking seasons. Therein, there were significant differences of bacterial communities in soils with cow manure fertilization (CMF) and urea fertilization (UF) in three seasons: the relative abundance of Bacteroidetes in CMF was significantly higher than that in UF and CK in spring, and the relative abundance of Proteobacteria and Bacteroidetes in CMF was significantly higher than that in UF and CK in autumn. So, the distribution of the dominant phyla was mainly affected by cow manure fertilization. The diversity of bacterial communities in soils with cow manure fertilization was higher than that in soils with urea fertilization, and was the highest in summer. Moreover, soil pH, OM and AK were important environmental properties affecting the soil bacterial community structure in tea plantation. CONCLUSIONS: Although different fertilizers and seasons affect the diversity and structure of soil microorganisms, the application of cow manure can not only improve the diversity of soil bacteria, but also effectively regulate the structure of soil bacterial community in tea plantation. So, cow manure fertilization is more suitable for tea plantation.


Assuntos
Bactérias/classificação , Esterco/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Chá/crescimento & desenvolvimento , Agricultura , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Bovinos , DNA Bacteriano/genética , DNA Ribossômico/genética , Fertilização , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Filogenia , Microbiologia do Solo , Chá/química
12.
BMC Genomics ; 21(1): 411, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32552744

RESUMO

BACKGROUND: Fulvic acid (FA) is a kind of plant growth regulator, which can promote plant growth, play an important role in fighting against drought, improve plant stress resistance, increase production and improve quality. However, the function of FA in tea plants during drought stress remain largely unknown. RESULTS: Here, we examined the effects of 0.1 g/L FA on genes and metabolites in tea plants at different periods of drought stress using transcriptomics and metabolomics profiles. Totally, 30,702 genes and 892 metabolites were identified. Compared with controlled groups, 604 and 3331 differentially expressed metabolite genes (DEGs) were found in FA-treated tea plants at 4 days and 8 days under drought stress, respectively; 54 and 125 differentially expressed metabolites (DEMs) were also found at two time points, respectively. Bioinformatics analysis showed that DEGs and DEMs participated in diverse biological processes such as ascorbate metabolism (GME, AO, ALDH and L-ascorbate), glutathione metabolism (GST, G6PDH, glutathione reduced form and CYS-GYL), and flavonoids biosynthesis (C4H, CHS, F3'5'H, F3H, kaempferol, quercetin and myricetin). Moreover, the results of co-expression analysis showed that the interactions of identified DEGs and DEMs diversely involved in ascorbate metabolism, glutathione metabolism, and flavonoids biosynthesis, indicating that FA may be involved in the regulation of these processes during drought stress. CONCLUSION: The results indicated that FA enhanced the drought tolerance of tea plants by (i) enhancement of the ascorbate metabolism, (ii) improvement of the glutathione metabolism, as well as (iii) promotion of the flavonoids biosynthesis that significantly improved the antioxidant defense of tea plants during drought stress. This study not only confirmed the main strategies of FA to protect tea plants from drought stress, but also deepened the understanding of the complex molecular mechanism of FA to deal with tea plants to better avoid drought damage.


Assuntos
Ácido Ascórbico/metabolismo , Benzopiranos/farmacologia , Vias Biossintéticas/efeitos dos fármacos , Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/efeitos dos fármacos , Camellia sinensis/genética , Camellia sinensis/metabolismo , Secas , Flavonoides/biossíntese , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Metabolômica , Proteínas de Plantas/genética , Estresse Fisiológico
13.
J Phys Condens Matter ; 32(3): 035401, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31539895

RESUMO

We study the ground-state phases of two-dimensional spin-orbit coupled spin-2 Bose-Einstein condensates in a one-dimensional spin-dependent optical lattice. Due to the competition among optical lattice, spin-orbit coupling and spin-exchange interaction, the exotic ground-state phases are found, i.e. three types of the stripe phases and three types of the supersolid phases. The spin-exchange interaction can adjust the direction of the stripe in the stripe phase and generate various vortex lattice structures in the supersolid phase, which shows that the spin-exchange interaction plays an important role in the formation of the stripe and supersolid phases of spin-orbit coupled spin-2 Bose-Einstein condensates in an optical lattice.

14.
Opt Express ; 27(13): 18794-18802, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31252816

RESUMO

Optical vortices, carrying quantized orbital angular momentum (OAM) states, have been widely investigated because of their promising applications in both classical and quantum realms. Among these applications, efficient generation and measurement of OAM beams are critical. Current techniques available for generating OAM beams generally suffer from bulky size, low operation efficiency, or single-function or complicated fabrication processes. Here we propose and experimentally demonstrate an approach to generate arbitrary optical vortices with a chip-scale device based on all-dielectric two-dimensional (2D) polarization-independent metasurface grating. Based on multi-beam interference in principle and nanofabrication techniques for implementation, our device allows efficient and simultaneous on-chip generation of multi-channel beams with different OAM. We further demonstrate that our device can also work reversely in detecting the OAM spectrum of various pure and mixed optical vortices (e.g., fractional OAM orders) with low crosstalk. Our scheme may find potential applications in developing new integrated photonics for OAM-based high-dimensional quantum information processing in future quantum network.

15.
Oncol Lett ; 16(3): 3207-3214, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30127916

RESUMO

Previous studies have reported that scinderin (SCIN) affects multiple cellular processes, including proliferation, migration and differentiation in cancer. However, the specific role of SCIN in breast cancer (BC) cells is unknown. Immunohistochemistry was used to investigate SCIN expression in 46 BC and 21 mammary fibroadenoma or fibroadenomatoid hyperplasia tissue samples. SCIN expression was ablated in MDA-MB-231 and T-47D cells using lentivirus-mediated small interfering RNA technology. Cell proliferation was tested using Celigo and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Cell apoptosis was analyzed by measuring Caspase 3/7 activity and annexin-V staining. The results of the present study demonstrated that SCIN expression was elevated in BC tissues compared with mammary fibroadenoma or fibroadenomatoid hyperplasia tissues. Specifically, higher SCIN expression was observed in Ki-67-positive BC tissues (78.6%) compared with Ki-67-negative BC tissues. Furthermore, knockdown of SCIN expression in the BC cell lines significantly suppressed cell proliferation and induced apoptosis. The data presented in the present study indicate that SCIN serves an important role in the development of breast cancer.

16.
J Phys Condens Matter ; 30(29): 295404, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29897338

RESUMO

We study the ground-state phases of two-dimensional spin-orbit coupled spin-1 Bose-Einstein condensate loaded in a plane quadrupole field. In the absence of rotation, for the fixed spin-orbit coupling strength, the ordinary stripe phase is found when the strength of the magnetic field gradient is small. As the strength of magnetic field gradient enhances, the system realizes the phases with three layer vortices along the radial direction. The number of vortices in the second layer is successively increased and the vortices in the outermost layer disappear when the strength of magnetic field gradient surpass the critical value. For the large strength of magnetic field gradient, the system only has the inner layer vortices. The magnetic field inhibits the region of vortices. For the fixed magnetic field gradient strength, the vortices of the system elongate along the radial direction and form a series of vortex lines, the number of the vortex line increases as the strength of spin-orbit coupling enhances. By adding the rotation, for the fixed strengths of spin-orbit coupling and magnetic field gradient, the number of second layer vortices also successively increases as the rotational frequency increases. The number of vortices in the certain layer of the ground-state density can be regularly changed under the effects of the magnetic field and spin-orbit coupling.

17.
Eur J Pharmacol ; 674(2-3): 73-9, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22044919

RESUMO

In chondrocytes, resveratrol, a natural SIRT1 activator, exerts an anti-inflammatory response via inhibition of nuclear factor kappaB (NF-κB). Given that SIRT1 inhibits the transactivation potential of NF-κB by deacetylating acetylated lysines in p65, the NF-κB subunit, we investigated the effects of resveratrol-activated SIRT1 on articular chondrocytes. We found that when chondrocytes were stimulated with interleukin 1ß (IL-1ß), the time- and dose-dependent expression of inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production was suppressed by resveratrol. Resveratrol-activated SIRT1 mediated this suppression. SIRT1 suppressed not only the nuclear translocation of NF-κB but also the acetylation of p65. Furthermore, acetylated Lys310 in p65, which must be present for transactivation activity, was the immediate downstream target of SIRT1. Therefore, SIRT1 protects against the inflammatory response induced by IL-1ß in articular chondrocytes. Resveratrol, as an activator of SIRT1, merits consideration as a therapeutic agent in the treatment and prevention of osteoarthritis.


Assuntos
Condrócitos/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/farmacologia , Óxido Nítrico Sintase Tipo II/biossíntese , Sirtuína 1/metabolismo , Estilbenos/farmacologia , Fator de Transcrição RelA/antagonistas & inibidores , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Condrócitos/citologia , Condrócitos/enzimologia , Condrócitos/metabolismo , DNA/metabolismo , Articulações/citologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Osteoartrite/tratamento farmacológico , Ratos , Ratos Wistar , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/uso terapêutico , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Ativação Transcricional/efeitos dos fármacos
18.
Chin J Integr Med ; 16(1): 41-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20131035

RESUMO

OBJECTIVE: Changes of the internal and external cellular environments can induce calcium homeostasis disorder and unfolded protein aggregation in the endoplasmic reticulum (ER). This ER function disorder is called endoplasmic reticulum stress (ERS). Severe long-term ERS can trigger the ER apoptosis signaling pathway, resulting in cell apoptosis and organism injury. Recent researches revealed that ERS-induced cell death was involved in the neurocyte retrogradation in the progress of neuron degenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease and so on. Therefore, the protection effect of the traditional Chinese drug-Tiantai No. 1 (1) on the ERS injury of AD was investigated at the molecular gene level in this study with a view to explore the gene pharmacodynamic actions and mechanisms of this drug. METHODS: Primarily cultured marrow mesenchymal stem cells (MSCs) of rats were treated by tunicamycin (TM) in order to induce ERS. RT-PCR, fluorescence immunocytochemistry and Western blot techniques were used to determine the mRNA and protein expression levels of the protective stress protein-ER molecular chaperones GRP78 and GRP94 (which would assist cells to resist cellular stress injury), and to determine the mRNA and protein expression levels of apoptosis promoting molecule Caspase-12 on the membrane of the ER, respectively. RESULTS: Protein expression levels of GRP78 and GRP94 were significantly increased in the TM-induced MSCs, and the mRNA level of Caspase-12 was also remarkably increased in the TM-induced MSCs (P<0.05). All these proved that the ERS model was successfully established by TM in MSC. Meanwhile, the mRNA and protein levels of GRP78 and GRP94 were all significantly increased compared with the model group (P<0.05 or P<0.01) after MSCs were treated with Tiantai No.1 while the mRNA and protein expression levels of Caspase-12 were significantly decreased compared with the model group (P<0.05 or P<0.01). This effect showed a dose dependent manner. CONCLUSION: Tiantai No.1 might attenuate the cell apoptosis induced by ERS injury, and thus protect the neurons against AD.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Tunicamicina/antagonistas & inibidores , Tunicamicina/farmacologia , Animais , Antibacterianos/antagonistas & inibidores , Antibacterianos/farmacologia , Células Cultivadas , Antagonismo de Drogas , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , RNA/análise , RNA/efeitos dos fármacos , Coelhos , Ratos , Ratos Sprague-Dawley , Estresse Fisiológico/genética
19.
World J Gastroenterol ; 15(7): 865-70, 2009 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-19230049

RESUMO

AIM: To explore the method for early diagnosis of gastric cancer by screening the expression spectrum of saliva protein in gastric cancer patients using mass spectrometry for proteomics. METHODS: Proportional peptide mass fingerprints were obtained by analysis based on proteomics matrix-assisted laser desorption ionization time-of-flight/mass spectrometry. A diagnosis model was established using weak cation exchange magnetic beads to test saliva specimens from gastric cancer patients and healthy subjects. RESULTS: Significant differences were observed in the mass to charge ratio (m/z) peaks of four proteins (1472.78 Da, 2936.49 Da, 6556.81 Da and 7081.17 Da) between gastric cancer patients and healthy subjects. CONCLUSION: The finger print mass spectrum of saliva protein in patients with gastric cancer can be established using gastric cancer proteomics. A diagnostic model for distinguishing protein expression mass spectra of gastric cancer from non-gastric-cancer saliva can be established according to the different expression of proteins 1472.78 Da, 2936.49 Da, 6556.81 Da and 7081.17 Da. The method for early diagnosis of gastric cancer is of certain value for screening special biological markers.


Assuntos
Proteômica/métodos , Proteínas e Peptídeos Salivares/análise , Neoplasias Gástricas/diagnóstico , Detecção Precoce de Câncer , Humanos , Peso Molecular , Mucoproteínas/análise , Mapeamento de Peptídeos , Valores de Referência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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