Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Molecules ; 27(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35630659

RESUMO

The study on the mechanism and kinetics of mRNA degradation provides a new vision for chemical intervention on protein expression. The AU enrichment element (ARE) in mRNA 3'-UTR can be recognized and bound by the ARE binding protein (AU-rich Element factor (AUF1) to recruit RNase for degradation. In the present study, we proposed a novel strategy for expression regulation that interferes with the AUF1-RNA binding. A small-molecule compound, JNJ-7706621, was found to bind AUF1 protein and inhibit mRNA degradation by screening the commercial compound library. We discovered that JNJ-7706621 could inhibit the expression of AUF1 targeted gene IL8, an essential pro-inflammatory factor, by interfering with the mRNA homeostatic state. These studies provide innovative drug design strategies to regulate mRNA homeostasis.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo D , Regiões 3' não Traduzidas , Ribonucleoproteína Nuclear Heterogênea D0 , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(10): 2858-62, 2014 Oct.
Artigo em Zh | MEDLINE | ID: mdl-25739238

RESUMO

Long Wavelength Near InfraRed (LW-NIR) spectrometer has wide applications. Miniaturization and low-cost are two major goals of the development of LW-NIR spectrometer in the industrial or research community. Under the background that having a trend of spectrometer miniaturization and integration, method and main problems involved in miniaturization of LW-NIR spectrometer through MEMS scanning mirror, such as the design strategy of the light-splitting optical system, selection considerations of the MEMS scanning mirror, design method of the preamplifier circuit, etc, have been presented in detail. A prototype of miniaturized LW-NIR spectrometer, with the spectrum range of detection of 900-2,055 nm, is designed and implemented using MEMS scanning mirror, InGaAs single detector unit with high sensitivity. Littrow optical layout is used for its light-splitting optical system, and the spectral resolution is between 9.4-16 nm at 1,000-1,965 nm detection wavelength range. The prototype is successfully applied in LW-NIR spectrum measurement on pure water and ethanol aqueous solution, and a forecast analysis on ethanol aqueous solution concentration is also demonstrated. Through adopting MEMS scanning mirror into the spectrometer system, the complexity of the mechanical scanning fixtures and its controlling mechanism is greatly reduced therefore the size of the spectrometer is reduced. Furthermore, due to MEMS scanning mirror technology, LW-NIR spectrometer with single InGaAs detector is achieved, thus the cost reduction of the NIR spectrometer system is also realized because the expensive InGaAs arrays are avoided.

3.
Mol Biol Rep ; 40(4): 2947-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23440515

RESUMO

SGT1 (suppressor of G2 allele of Skp1) plays a role in various cellular processes including kinetochore assembly and protein ubiquitination by interacting with Skp1, a component of SCF E3 ligase complex. However, the function of SGT1 in cancer is largely unknown. Here, we showed that SGT1 was over-expressed in gastric cancer tissues and silencing of SGT1 by siRNAs significantly inhibited the growth and colony formation of gastric cancer cells. We further showed that SGT1 could regulate Akt signaling pathway by modulating Akt ser473 phosphorylation status. Moreover, we found that SGT1 was able to regulate the stability of PHLPP1, which is the direct phosphatase for Akt ser473 phosphorylation. Immunoprecipitation assay revealed that SGT1 could enhance the binding between PHLPP1 and beta-TrCP which has been documented to be able to target PHLPP1 for destruction. Decreased PHLPP1 in SGT1 over-expressed gastric cancer cells failed to dephosphorylate Akt and resulted in increased Akt ser473 phosphorylation and amplified downstream Akt signaling. Thus, our data revealed a previously uncovered role of SGT1 in gastric cancer development, and suggested that SGT1 could be a promising anti-cancer target to against gastric cancer.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Proteína Oncogênica v-akt/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Neoplasias Gástricas/genética , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Fosforilação , Ligação Proteica , Proteólise , RNA Interferente Pequeno , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
4.
Eur J Med Chem ; 232: 114200, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35219149

RESUMO

Since more than 85% of lung cancer cases are non-small cell lung cancer (NSCLC), finding novel agents with anti-tumor activities is meaningful for NSCLC patients. Mitochondria is essential for cellular energy metabolism in cancer, and regulating mitochondrial bioenergetics is emerging as a practical approach for cancer treatment and prevention. The carbazole scaffold is an active structure showing anti-cancer biological activity, and the structural diversity has been expanded through the improvement and optimization of synthesizing methods. To find novel carbazole derivatives with great anti-tumor potential and explore structures variety, we designed and synthesized a series of 9-(pyrimidin-2-yl)-9H-carbazole derivatives based on the previously reported Cp∗Rh(III)/H+ tandem catalytic system. With thoroughly bioactivity exploration, we found benzo[d] [1,3]dioxol-5-yl(9-(pyrimidin-2-yl)-9H-carbazol-1-yl)methanone (compound 5n) showed notable activity in disrupting the mitochondrial homeostasis, induced cell cycle arrest and apoptosis in human adenocarcinoma cells, and finally showed anti-tumor activity in an NSCLC-xenograft mice model.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Carbazóis/química , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Homeostase , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Mitocôndrias/metabolismo
5.
Front Bioeng Biotechnol ; 9: 638971, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763410

RESUMO

Microalgae, as potential biodiesel feedstocks, have been widely reported to accumulate oil via genetic engineering techniques, or environmental stress regulation. Recently, the utilization of fuel cell technology to convert biomass into electricity has attracted much more attention due to its high efficiency, low pollution, low noise by microalgae as feedstocks. Normally, platinum and analogous noble metals as catalysts have been already demonstrated although they still exist lots of shortcomings. This mini review presents an overview of various fuel cell technologies with phosphomolybdic acid as catalysts for sustainable energy by using microalgae. Trends from literatures demonstrate that algal-based fuel cells could efficiently generate electricity, and concurrently produce high value-added products. This critical review can provide guiding suggestions for future study of algal-based energy conversion by fuel cell techniques.

6.
Org Lett ; 23(12): 4677-4682, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34048268

RESUMO

Here a facile synthesis strategy toward carboxylated leaning tower[6]arene (CLT6)-mediated gold nanoparticles (CLT6-AuNPs) without external energy sources and reducing agents has been developed. Due to the cavity structure of CLT6, CLT6-AuNPs with a controllable particle size show good stability and excellent performance in label-free detection of diquat. Significantly, we reveal the reduction mechanism of AuNP formation, which is the cleavage of some phenyl ether bonds of CLT6 to produce reductive phenols, thus reducing Au3+ to AuNPs.

7.
Sci Rep ; 10(1): 2639, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060329

RESUMO

Plasma trimethylamine N-oxide (TMAO) is associated with coronary atherosclerotic plaque and cardiovascular disease risk, but associations between gut microbes in acute coronary syndrome (ACS) and post-ST-segment elevation myocardial infarction (post-STEMI) events are unknown. We investigated associations between gut microbial taxa and systemic TMAO levels and the possible TMAO contribution to incident post-STEMI cardiovascular events. PATIENTS AND METHODS: A total of 60 patients, including 30 with unstable angina pectoris (UAP), 30 post-STEMI and 30 healthy controls, were enrolled from June to November 2017. Metagenomic sequencing was performed and TMAO and IL-6 were detected. RESULTS: Minimal discriminators of gut microbial taxa (top 40) distinguished ACS patients from controls. Serum TMAO levels were positively associated with increased abundance of Aerococcaceae, Ruminococcaceae_UCG.005, Ruminococcaceae_UCC.014 and X. Eubacterium_fissicatena, and decreased abundance of Lachnospiraceae_FCS020 (P < 0.05). Elevated serum TMAO levels correlated independently with ACS (P < 0.05). Risk stratification for incident major adverse cardiovascular events (MACE) improved at one year in patients with serum TMAO levels ≦2.19 µM. Serum interleukin-6 levels were not significantly increased in patients with ACS and post-STEMI MACE. CONCLUSIONS: ACS and incident post-STEMI MACE may be associated with the gut bacteria choline metabolite TMAO. The specific gut microbial taxa identified in association with serum TMAO levels may be potential predictive biomarkers for accurate diagnosis of ACS onset.


Assuntos
Síndrome Coronariana Aguda/microbiologia , Microbioma Gastrointestinal , Infarto do Miocárdio com Supradesnível do Segmento ST/microbiologia , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Metilaminas/sangue , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2330-3, 2009 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19950622

RESUMO

Primary investigation of Platymonas subcordiformis was performed with laser scanning microscopic technology. Both autofluorescence spectra and autofluorescence imaging of Platymonas subcordiformis were achieved by one photon excitation of 488 nm Ar+ laser. Autofluorescence images revealed cup-shaped object inside the Platymonas subcordiformis cell, and the corresponding fluorescence peak located at 682 nm was attributed to chloroplast. Moreover, in single channel mode, there existed a round-shaped object in chloroplast center, showing strong fluorescence by 800 nm femtosecond laser excitation. Also, the authors obtained both the individual cup-shaped chloroplast and round-shaped object image and the overlaid images by using dual-channel mode. Meanwhile, six main fluorescence peaks were found. Single photon excitation can be used to obtain autofluorescence image and autofluorescence spectra of Platymonas subcordiformis, while two photon excitation combined with multitrack mode and Lambda mode can be used not only to observe internal structure, but also for the analysis of existence of biological and chemical substances with higher sensitivity than single photon excitation. LSCM technique can be a promising tool for rapid, convenient, real-time and effective investigation in ocean algae.


Assuntos
Clorófitas , Fluorescência , Cloroplastos , Lasers , Luz , Microscopia Confocal , Microscopia de Fluorescência por Excitação Multifotônica , Fótons
9.
Medicine (Baltimore) ; 97(37): e12246, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30212958

RESUMO

The diagnosis of dilated cardiomyopathy (DCM) remains a challenge in clinical radiology. This study aimed to investigate whether texture analysis (TA) parameters on magnetic resonance T1 mapping can be helpful for the diagnosis of DCM.A total of 50 DCM cases were retrospectively screened and 24 healthy controls were prospectively recruited between March 2015 and July 2017. T1 maps were acquired using the Modified Look-Locker Inversion Recovery (MOLLI) sequence at a 3.0 T MR scanner. The endocardium and epicardium were drawn on the short-axis slices of the T1 maps by an experienced radiologist. Twelve histogram parameters and 5 gray-level co-occurrence matrix (GLCM) features were extracted during the TA. Differences in texture features between DCM patients and healthy controls were evaluated by t test. Support vector machine (SVM) was used to calculate the diagnostic accuracy of those texture parameters.Most histogram features were higher in the DCM group when compared to healthy controls, and 9 of these had significant differences between the DCM group and healthy controls. In terms of GLCM features, energy, correlation, and homogeneity were higher in the DCM group, when compared with healthy controls. In addition, entropy and contrast were lower in the DCM group. Moreover, entropy, contrast, and homogeneity had significant differences between these 2 groups. The diagnostic accuracy when using the SVM classifier with all these histogram and GLCM features was 0.85 ±â€Š0.07.A computer-based TA and machine learning approach of T1 mapping can provide an objective tool for the diagnosis of DCM.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Máquina de Vetores de Suporte
10.
J Agric Food Chem ; 62(35): 8773-6, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-25109502

RESUMO

Microalgae are important primary producers in the marine ecosystem and excellent sources of lipids and other bioactive compounds. The marine diatom Phaeodactylum tricornutum accumulates eicosapentaenoic acid (EPA, 20:5n-3) as its major component of fatty acids. To improve the EPA production, delta 5 desaturase, which plays a role in EPA biosynthetic pathway, was characterized in P. tricornutum. An annotated delta 5 desaturase PtD5b gene was cloned and overexpressed in P. tricornutum. The transgene was integrated into the genome demonstrated by Southern blot, and the overexpression of PtD5b was verified by qPCR and Western blot analysis. Fatty acid composition exhibited a significant increase in the unsaturated fatty acids. Monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) showed an increase of 75% and 64%, respectively. In particular, EPA showed an increase of 58% in engineered microalgae. Meanwhile, neutral lipid content showed an increase up to 65% in engineered microalgae. More importantly, engineered cells showed a similar growth rate with the wild type, thus keeping high biomass productivity. This work provides an effective way to improve the production of microalgal value-added bioproducts by metabolic engineering.


Assuntos
Diatomáceas/enzimologia , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/biossíntese , Microalgas/enzimologia , Vias Biossintéticas , Dessaturase de Ácido Graxo Delta-5 , Diatomáceas/química , Diatomáceas/genética , Diatomáceas/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Insaturados/química , Microalgas/química , Microalgas/genética , Microalgas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA