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1.
Anal Chem ; 95(23): 9014-9024, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37260031

RESUMO

The precise regulation of the electron-withdrawing/electron-donating strength in a probe is of great significance for the design of reaction-based fluorescent probes with specific functionalities. Here, a family of excited-state intramolecular proton transfer (ESIPT)-based probes with fluorescence turn-on sensing properties toward KMnO4 was designed by precisely modulating the electron-withdrawing strength of the substituents located at the para-position of the recognition group. It is found that -F, -CHO, and -H as the electron-withdrawing groups bound at the probe can specifically recognize KMnO4, which ensures a blue emission displayed by the reaction products. Especially with -CHO as the electron-withdrawing group, the reaction product shows the most stable fluorescence. The probe 2-(benzo[d]oxazol-2-yl)-4-formylphenyl acrylate (BOPA-CHO) demonstrated a more superior sensing performance toward KMnO4, including a low limit of detection (LOD, 0.96 nM), a rapid response (<3 s), and a rather good selectivity even in the presence of 21 interferents. Moreover, the practicality of the probe was further verified by a test pen comprising a BOPA-CHO-embedded sponge, which is capable of detecting KMnO4 solid with a naked-eye LOD of 11.62 ng. The present probe design and modulation strategy would open up a new path for the design of high-performance fluorescent probes.

2.
Org Biomol Chem ; 21(2): 315-322, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36524697

RESUMO

A deep understanding of the fluorescence response mechanisms is the foundation for design-oriented strategies for D-π-A probes for trace hazardous chemicals. Here, from the perspective of electronegativity regulation of the π-bridge recognition site, an electron-donation modulation strategy involving various comprehensive evaluations of the optical and chemical properties is proposed through a series of theoretical analyses. Due to the preferential combined interaction between the π-bridge recognition site and MnO4-, high electrophilic reactivity and feasible chemical reaction energy barrier, a high-performance filter paper chip and hydrogel chip for the detection of aqueous and air-suspended environmental KMnO4 was achieved. We expect the present modulation strategy will facilitate efficient fluorescent probe design and provide a universal methodology for the exploration of functional D-π-A molecules.


Assuntos
Elétrons , Corantes Fluorescentes , Corantes Fluorescentes/química , Teoria da Densidade Funcional , Fluorescência
3.
Environ Res ; 239(Pt 1): 117372, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37827365

RESUMO

Perfluorooctanoic acid (PFOA) is a highly persistent and widespread chemical in the environment with endocrine disruption effects. Although it has been reported that PFOA can affect multiple aspects of thyroid function, the exact mechanism by which it reduces thyroxine levels has not yet been elucidated. In this study, FRTL-5 rat thyroid follicular cells were used as a model to study the toxicity of PFOA to the genes related to thyroid hormone synthesis and their regulatory network. Our results reveal that PFOA interfered with the phosphorylation of the cyclic adenosine monophosphate (cAMP)-response element binding protein (CREB) induced by thyroid-stimulating hormone (TSH), as well as the transcription levels of paired box 8 (PAX8), thyroid transcription factor 1 (TTF1), sodium/iodide cotransporter (NIS), thyroglobulin (TG), and thyroid peroxidase (TPO). However, the above outcomes can be alleviated by enhancing cAMP production with forskolin treatment. Further investigations showed that PFOA reduced the mRNA level of TSH receptor (TSHR) and impaired its N-glycosylation, suggesting that PFOA has disrupting effects on both transcriptional regulation and post-translational regulation. In addition, PFOA increased endoplasmic reticulum (ER) stress and decreased ER mass in FRTL-5 cells. Based on these findings, it can be inferred that PFOA disrupts the TSH-activated cAMP signaling pathway by inhibiting TSHR expression and its N-glycosylation. We propose that this mechanism may contribute to the decrease in thyroid hormone levels caused by PFOA. Our study sheds light on the molecular mechanism by which PFOA can disrupt thyroid function and provides new insights and potential targets for interventions to counteract the disruptive effects of PFOA.


Assuntos
Caprilatos , Fluorocarbonos , Receptores da Tireotropina , Glândula Tireoide , Tireotropina , Fluorocarbonos/farmacologia , Caprilatos/farmacologia , Glândula Tireoide/efeitos dos fármacos , Transdução de Sinais , Animais , Ratos , Tireotropina/metabolismo , Receptores da Tireotropina/metabolismo , Processamento de Proteína Pós-Traducional , Glicosilação , Estresse do Retículo Endoplasmático , Regulação da Expressão Gênica/efeitos dos fármacos , Linhagem Celular
4.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-37942557

RESUMO

The off-flavor of Pichia pastoris strains is a negative characteristic of proteins overexpressed with this yeast. In the present study, P. pastoris GS115 overexpressing an α-l-rhamnosidase was taken as the example to characterize the off-flavor via sensory evaluation, gas chromatography-mass spectrometer, gas chromatography-olfaction, and omission test. The result showed that the off-flavor was due to the strong sweaty note, and moderate metallic and plastic notes. Four volatile compounds, that is, tetramethylpyrazine, 2,4-di-tert-butylphenol, isovaleric acid, and 2-methylbutyric acid, were identified to be major contributors to the sweaty note. Dodecanol and 2-acetylbutyrolactone were identified to be contributors to the metallic and plastic notes, respectively. It is the first study on the off-flavor of P. pastoris strains, helping understand metabolites with off-flavor of this yeast. Interestingly, it is the first study illustrating 2-acetylbutyrolactone and dodecanol with plastic and metallic notes, providing new information about the aromatic contributors of biological products. IMPORTANCE: The methylotrophic yeast Pichia pastoris is an important host for the industrial expression of functional proteins. In our previous studies, P. pastoris strains have been sniffed with a strong off-flavor during the overexpression of various functional proteins, limiting the application of these proteins. Although many yeast strains have been reported with off-flavor, no attention has been paid to characterize the off-flavor in P. pastoris so far. Considering that P. pastoris has advantages over other established expression systems of functional proteins, it is of interest to identify the compounds with off-flavor synthesized in the overexpression of functional proteins with P. pastoris strains. In this study, the off-flavor synthesized from P. pastoris GS115 was characterized during the overexpression of an α-l-rhamnosidase, which helps understand the aromatic metabolites with off-flavor of P. pastoris strains. In addition, 2-acetylbutyrolactone and dodecanol were newly revealed with plastic and metallic notes, enriching the aromatic contributors of biological products. Thus, this study is important for understanding the metabolites with off-flavor of P. pastoris strains and other organisms, providing important knowledge to improve the flavor of products yielding with P. pastoris strains and other organisms. ONE-SENTENCE SUMMARY: Characterize the sensory and chemical profile of the off-flavor produced by one strain of P. pastoris in vitro.


Assuntos
Produtos Biológicos , Saccharomyces cerevisiae , Pichia/genética , Pichia/metabolismo , Produtos Biológicos/metabolismo , Dodecanol/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
5.
Anal Chem ; 94(33): 11679-11687, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35948453

RESUMO

Inhibition of twisting intramolecular charge transfer (TICT) is one of the most attractive methods for fluorescence-on analysis, whereas it remains enigmatic whether the fluorescence in a TICT-based probe could be thoroughly lightened. Here, for maximizing the fluorescence-on signal of the TICT-based probe, we develop a model by employing chemical reaction to directly cleave the linkage between the rotational electron donor and acceptor with a predisposed fluorescent signal close to zero. To validate this assumption, a nonfluorescent probe with barrierless rotation is successfully achieved by grafting acryloyl with -C═C- recognition sites onto coumarin, and 7-hydroxycoumarin with bright blue fluorescence could be released within 3 s upon probing KMnO4 with an amount as low as 0.95 nM and 6.6 pg. We believe that the present strategy could not only deepen the insights of photochemistry but also facilitate the development of a theranostic drug delivery system, energy conversion, pollution control, and health risk reduction.


Assuntos
Corantes , Fluorescência , Fotoquímica , Rotação
6.
Anal Chem ; 94(25): 9184-9192, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35713422

RESUMO

Although a set of functional molecules with the D-π-A structure has been explored as optical probes for the detection of target analytes, it remains a great challenge to elaborately design a single probe for distinguishing different analytes by their intrinsic oxidation or reduction capabilities and thus to generate distinct optical responses. Here, a unique TCF-based probe (DMA-CN) containing two unsaturated double bonds in the π-conjugation bridge and TCF with different reaction activities that could be cut off by KMnO4 and NaClO in varying degrees was developed, causing remarkably distinguishable responses for both fluorescence and colorimetric channels to discriminate KMnO4 and NaClO from each other. The fluorescence and colorimetric limits of detection (LODs) of the proposed DMA-CN toward KMnO4 were calculated as 60 and 91 nM, respectively, while those for NaClO were 13.3 and 214 nM, and all the optical signal change can be observed within 1 s with good specificity. Based on the proposed probe design strategy, a well-fabricated test strip was proven to be promising for the rapid, in-field detection and risk management. We expect that the present probe design methodology would provide a powerful strategy for efficient probe exploration, especially for discriminating the substances with similar oxidizing properties.


Assuntos
Colorimetria , Oxidantes , Colorimetria/métodos , Limite de Detecção , Oxirredução
7.
Ecotoxicol Environ Saf ; 236: 113508, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35427876

RESUMO

Perfluorooctanoate acid (PFOA) is a highly persistent and widespread chemical in the environment. PFOA serum levels in pregnant women are positively associated with an increased risk of placenta-related disorders. However, the mechanism of PFOA cytotoxicity involved in placental cells and cellular responses such as ER stress remains poorly understood. In this study, we studied the cellular toxicity of PFOA with a focus on proliferation and apoptosis in a human placental trophoblast cell line. Cell viability, number, apoptosis, stress response, activation of the involved signaling pathways were assessed. Our results showed PFOA affected cell viability, proliferation and also resulted in apoptosis. Besides, both pro-proliferation and pro-apoptosis effects were attenuated by endoplasmic reticulum (ER) stress inhibitors. Further experiments demonstrated that two different signaling pathways were activated by PFOA-induced ER stress and involved in PFOA toxicity: the reactive oxygen species (ROS)-dependent ERK signaling triggered trophoblast proliferation, while the ATF4-dependent C/EBP homologous protein (CHOP) signaling was the trigger of apoptosis. We conclude that PFOA-induced ER stress is the trigger of proliferation and apoptosis of trophoblast via ROS or UPR signaling pathway, which leads to the altered balance critical to the normal development and function of the placenta.


Assuntos
Placenta , Trofoblastos , Apoptose , Caprilatos , Proliferação de Células , Estresse do Retículo Endoplasmático , Feminino , Fluorocarbonos , Humanos , Placenta/metabolismo , Gravidez , Espécies Reativas de Oxigênio/metabolismo , Trofoblastos/metabolismo
8.
Geriatr Nurs ; 47: 239-246, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36027785

RESUMO

OBJECTIVE: Current research on the effects of mindfulness therapy on MCI and insomnia has been inconsistent. It is still a hot topic of research and discussion. This study aimed to improve the sleep quality, cognition, and mental state of patients with mild cognitive impairment (MCI) with insomnia. METHODS: A double-blind randomized controlled trial was conducted. Seventy-five patients who met the eligibility criteria were randomly assigned to the mindfulness (n = 38) or health education (n = 37) treatment group. The primary outcomes were sleep, measured by the Pittsburgh Sleep Quality Inventory, and cognition, measured by The Montreal Cognitive Assessment and Mini-Mental State Examination. Secondary outcomes included insomnia, measured by the Insomnia Severity Index, depression, anxiety, and perceived stress. EEG signals were collected at rest with eyes closed in the mindfulness state. The power spectrum was analyzed from these data. RESULTS: Cognitive function and sleep quality were significantly improved in the mindfulness group (95% confidence interval 0.04 - 0.05, 0.03 - 0.04, -5.58 - -1.55, respectively). Anxiety and perceived stress scores were significantly lower than those in the control group (95% confidence interval 0.002 - 0.004, 0.009 - 0.013, respectively). The power spectrum differences in δ, θ, ß, and γ bands were significant between the rest and mindfulness states (P < .05). Good safety was achieved in both groups with no deaths or serious adverse events. CONCLUSION: Mindfulness improved sleep quality, cognitive function, and mentality of patients. Mindfulness practice caused deep relaxation in the brain and changes in electrical frequency bands associated with attention and cognitive tasks. Mindfulness learning can be performed successfully for individuals with MCI. Additionally, it is suitable for adoption in nursing homes.


Assuntos
Disfunção Cognitiva , Atenção Plena , Distúrbios do Início e da Manutenção do Sono , Disfunção Cognitiva/terapia , Humanos , Sono , Distúrbios do Início e da Manutenção do Sono/terapia , Resultado do Tratamento
9.
Ecotoxicol Environ Saf ; 220: 112389, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082246

RESUMO

Triclosan (TCS) is an endocrine-disrupting chemical (EDC), which is used ubiquitously as an antimicrobial ingredient in healthcare products and causes contamination in the environment such as air, water, and biosolid-amended soil. Exposure to TCS may increase the risk of reproduction diseases and health issues. Several groups, including ours, have proved that TCS increased the biosynthesis of steroid hormones in different types of steroidogenic cells. However, the precise mechanism of toxic action of TCS on increased steroidogenesis at a molecular level remains to be elucidated. In this study, we try to address the mode of action that TCS affects energy metabolism with increased steroidogenesis. We evaluated the adverse effects of TCS on energy metabolism and steroidogenesis in human ovarian granulosa cells. The goal is to elucidate how increased steroidogenesis can occur with a shortage of adenosine triphosphate (ATP) whereas mitochondria-based energy metabolism is impaired. Our results demonstrated TCS increased estradiol and progesterone levels with upregulated steroidogenesis gene expression at concentrations ranging from 0 to 10 µM. Besides, glucose consumption, lactate level, and pyruvate kinase transcription were increased. Interestingly, the lactate level was attenuated with increased steroidogenesis, suggesting that pyruvate fate was shifted away from the formation of lactate towards steroidogenesis. Our study is gathering evidence suggesting a mode of action that TCS changes energy metabolism by predominating glucose flow towards the biosynthesis of steroid hormones. To the best of our knowledge, this is the first report that TCS presents such toxic action in disrupting hormone homeostasis.


Assuntos
Anti-Infecciosos/toxicidade , Disruptores Endócrinos/toxicidade , Células da Granulosa/efeitos dos fármacos , Triclosan/toxicidade , Anaerobiose , Animais , Estradiol/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/metabolismo , Humanos , Progesterona/metabolismo
10.
Geriatr Nurs ; 42(1): 129-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33385772

RESUMO

Expressive arts therapy (EAT) can potentially improve cognition and mental health in patients with dementia. However, limited studies have been conducted for older adults with mild cognitive impairment (MCI). The aim of this study was to examine the effects of EAT in older adults with MCI. A total of 48 participants with MCI were assigned to the EAT intervention (n = 24) or waiting list control (n = 24) group. The former received 60-90 min of EAT twice a week for 6 weeks. The findings showed that the EAT program had a high retention and attendance rate and a high level of general satisfaction. Moreover, the intervention group showed significant improvements in general cognitive function, language function, anxiety, depression, and the psychological and social relationship domains of quality of life. The results provide preliminary evidence for the feasibility and efficacy of EAT intervention in older adults with MCI.


Assuntos
Disfunção Cognitiva , Qualidade de Vida , Idoso , Ansiedade/terapia , Cognição , Disfunção Cognitiva/terapia , Humanos , Projetos Piloto
11.
Arch Virol ; 165(11): 2531-2540, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32851429

RESUMO

Enterovirus 71 (EV71)-induced T lymphocyte apoptosis plays an important role in hand, foot, and mouth disease (HFMD), and granzyme B (GZMB) has been shown to be critical for this process. However, the mechanisms underlying GZMB-mediated apoptosis of T lymphocytes remain unknown. In this study, we investigated whether transcription factors and microRNAs (miRNAs) are involved in GZMB-mediated apoptosis of T lymphocytes in response to EV71 infection. Our findings indicated that EV71 infection significantly induced apoptosis in Jurkat cells, a human T lymphocytes cell line, as revealed in flow cytometric analysis. Furthermore, EV71 increased the expression of pro-apoptosis Bcl-2-associated X (Bax) and cleaved caspase 3 but decreased the expression of anti-apoptosis B-cell lymphoma protein 2 (Bcl2). GZMB knockdown decreased cell apoptosis and prevented EV71-induced changes in the expression of Bax, cleaved caspase 3, and Bcl2 in Jurkat cells, highlighting the role of GZMB as a key factor in EV71-induced apoptosis. Our study also indicated that overexpression of the transcription factors GATA binding factor 1 (GATA1) and specificity protein 1 (SP1) significantly increased luciferase activity when this gene was inserted in the GZMB 3' untranslated region (3'UTR). GATA1/SP1 overexpression induced cell apoptosis, increased the expression of Bax and cleaved caspase 3, and decreased the expression of Bcl2. Finally, our results suggested that miR-874 plays an essential role in GZMB-mediated cell apoptosis, since an miR-874 mimic decreases the expression of GZMB by targeting its 3'UTR. Collectively, these data indicated that GATA1/SP1 and miR-874 mediate EV71-induced apoptosis in a granzyme B-dependent manner. This signaling pathway may provide a new pharmacological target for the prevention and treatment of HFMD.


Assuntos
Enterovirus Humano A/genética , Infecções por Enterovirus/virologia , Fator de Transcrição GATA1/metabolismo , Granzimas/metabolismo , MicroRNAs/metabolismo , Fator de Transcrição Sp1/metabolismo , Apoptose , Caspase 3/imunologia , Enterovirus Humano A/fisiologia , Humanos , Células Jurkat , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
12.
Int J Mol Sci ; 20(11)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31195663

RESUMO

The Teosinte-branched 1/Cycloidea/Proliferating (TCP) plant-specific transcription factors (TFs) have been demonstrated to play a fundamental role in plant development and organ patterning. However, it remains unknown whether or not the TCP gene family plays a role in conferring a tolerance to drought stress in maize, which is a major constraint to maize production. In this study, we identified 46 ZmTCP genes in the maize genome and systematically analyzed their phylogenetic relationships and synteny with rice, sorghum, and Arabidopsis TCP genes. Expression analysis of the 46 ZmTCP genes in different tissues and under drought conditions, suggests their involvement in maize response to drought stress. Importantly, genetic variations in ZmTCP32 and ZmTCP42 are significantly associated with drought tolerance at the seedling stage. RT-qPCR results suggest that ZmTCP32 and ZmTCP42 RNA levels are both induced by ABA, drought, and polyethylene glycol treatments. Based on the significant association between the genetic variation of ZmTCP42 and drought tolerance, and the inducible expression of ZmTCP42 by drought stress, we selected ZmTCP42, to investigate its function in drought response. We found that overexpression of ZmTCP42 in Arabidopsis led to a hypersensitivity to ABA in seed germination and enhanced drought tolerance, validating its function in drought tolerance. These results suggested that ZmTCP42 functions as an important TCP TF in maize, which plays a positive role in drought tolerance.


Assuntos
Adaptação Fisiológica/genética , Secas , Genoma de Planta , Família Multigênica , Proteínas de Plantas/genética , Zea mays/genética , Zea mays/fisiologia , Ácido Abscísico/farmacologia , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Oryza/genética , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Sorghum/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Zea mays/efeitos dos fármacos
13.
Pak J Pharm Sci ; 32(5): 1933-1940, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31813855

RESUMO

Geniposide and baicalin, the main components of Huangqin-Zhizi herb pair, have been combined to increase the efficacy. To reveal the underlying compatibility mechanism of these two components, the synergistic effects of geniposide on the enhancement of solubility, apparent oil-water partition coefficient, and intestinal absorption of baicalin were investigated. The equilibrium solubility and apparent oil-water partition coefficient of baicalin in different solvents were determined through the shake-flask and high-performance liquid chromatography with diode array detection methods. The intestinal absorption of baicalin was investigated through the in situ single-pass intestinal perfusion method. When combined with different amounts of geniposide, the solubility and apparent oil-water partition coefficient of baicalin improved to 98.74-159.03µg/mL and 0.24-0.29, respectively, which were respectively 1.25-2.02-fold and 1.6-1.9-fold higher than those parameters in the baicalin-only control. The intestinal absorption study indicated that geniposide was an absorption-enhancer for baicalin and significantly increased the absorption rate constant value and the apparent absorption constant value of baicalin, especially in duodenum and jejunum when the compatibility concentrations were 1:1 and 1:2. Geniposide had synergistic effects in enhancing the solubility, apparent oil-water partition coefficient, intestinal absorption of baicalin. The study results provide scientific information elucidating the compatibility mechanism of the Huangqin-Zhizi herb pair and its primary components.


Assuntos
Flavonoides/farmacologia , Absorção Intestinal/efeitos dos fármacos , Iridoides/farmacologia , Solubilidade/efeitos dos fármacos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Duodeno/metabolismo , Jejuno/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
14.
Molecules ; 22(2)2017 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-28208662

RESUMO

In this study, we prepared solid dispersions (SDs) of 20(S)-protopanaxadiol (PPD) using a melting-solvent method with different polymers, in order to improve the solubility and dissolution performance of drugs with poor water solubility. The SDs were characterized via differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and molecular docking and dynamics study. DSC and PXRD results indicated that PPD crystallinity in SDs was significantly reduced, and that the majority of PPD is amorphous. No interaction was observed between PPD and polymers on FTIR and NMR spectra. Molecular docking and dynamic calculations indicated that the PPD molecule localized to the interpolated charged surface, rather than within the amorphous polymer chain network, which might help prevent PPD crystallization, consequently enhancing the PPD dispersion in polymers. An in vitro dissolution study revealed that the SDs considerably improved the PPD dissolution performance in distilled water containing 0.35% Tween-80 (T-80). Furthermore, among three PPD-SDs formulations, Poloxamer188 (F68) was the most effective in improving the PPD solubility and was even superior to the mixed polymers. Therefore, the SD prepared with F68 as a hydrophilic polymer carrier might be a promising strategy for improving solubility and in vitro dissolution performance. F68-based SD, containing PPD with a melting-solvent preparation method, can be used as a promising, nontoxic, quick-release, and effective intermediate for other pharmaceutical formulations, in order to achieve a more effective drug delivery.


Assuntos
Simulação de Acoplamento Molecular , Sapogeninas/química , Varredura Diferencial de Calorimetria , Ligantes , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular , Estrutura Molecular , Polímeros/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Phys Chem Chem Phys ; 18(36): 25553-25559, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27711463

RESUMO

In this work, a novel polymer thermo-optic switch with loss compensation function is successfully designed and fabricated by direct UV-writing technology. The waveguide core and cladding layer material of the switch are based on the low-loss fluorinated photopolymer and erbium-containing gain copolymer. The absorption loss characteristics and thermal stabilities of the core and cladding materials are studied. The optimal optical field distribution for loss-compensation structures is analyzed by modifying refractive index difference between the core and cladding. The thermo-optic modulation effect of the optical signal transmission for the device is simulated. The insertion loss of the switch device is about 6 dB. The switching rise and fall time are 396.2 µs and 461.2 µs applied by 500 Hz square-wave voltage, respectively. The switching power is 6.5 mW, the extinction ratio of the switch is about 14 dB. The loss-compensation value of the entire chip is obtained as 1.9 dB at 1530 nm wavelength. The flexible loss-compensation multi-functional waveguide switch is appropriate for incorporation in large-scale opti-electronic integrated circuits.

16.
J Transl Med ; 13: 293, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26351076

RESUMO

BACKGROUND: Interferons (IFNs) have potent anti-proliferative, pro-apoptotic, and immunomodulatory activities against cancer. However, the clinical utility of IFNs is limited by toxicity and pharmacokinetics making it difficult to achieve sustained therapeutic levels especially in solid tumors. METHODS: Signal Transducer and Activator of Transcription 1 (STAT1) or a modified STAT1 (designated STAT1-CC) that is hyper-responsive to IFN were overexpressed in lung cancer SPC-A-1 and H1299 cells using lentiviral vectors. Transduction efficiency was monitored using enhanced green fluorescent protein (EGFP) expression. After transduction, cells were treated with interferon-gamma (IFN-γ) or interferon-beta (IFN-ß) and monitored for cell proliferation, migration, and invasiveness using Cell Counting Kit-8 and transwell chamber assays and for apoptosis using Annexin V detection by flow cytometry. In addition, levels of STAT1, STAT1 Tyr-701 phosphorylation (pSTAT1), fibronectin, and ß-catenin were determined using western blotting. In the case of IFN-γ stimulation, levels of S100A4, proliferating cell nuclear antigen (PCNA), and c-fos expression were also determined. RESULTS: We found that expression of STAT1 or STAT1-CC enhanced the effect of IFN-γ and, IFN-ß on inhibition of human lung cancer cell proliferation, migration and invasiveness. Moreover, STAT1 and STAT1-CC expression caused increases in pSTAT1 and decreases in fibronectin and ß-catenin levels. STAT1-CC showed increased effects compared to STAT1 on IFN-γ induced pSTAT1 and down-regulation of S100A4, PCNA, and c-fos levels. CONCLUSION: The results show that STAT1-CC exhibited more strength in improving the antitumor response of IFNs in lung cancer cells. Results from this study suggest that combined treatment of IFNs and STAT1-CC might be a feasible approach for the clinical management of lung cancer in the future.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/metabolismo , Fator de Transcrição STAT1/química , Fator de Transcrição STAT1/genética , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Fibronectinas/metabolismo , Proteínas de Fluorescência Verde/química , Células HEK293 , Humanos , Interferon beta/farmacologia , Interferon gama/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Invasividade Neoplásica , Metástase Neoplásica , Fosforilação , beta Catenina/metabolismo
17.
Appl Opt ; 53(29): 6698-705, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25322371

RESUMO

Novel thermo-optic waveguide gate switch arrays were designed and fabricated based on the direct UV-written technique. Highly fluorinated low-loss photopolymers and organic-inorganic grafting materials were used as the waveguide core and cladding, respectively. The low absorption loss characteristics and excellent thermal stabilities of the core and cladding materials were obtained. The rectangular waveguides and arrayed electrode heaters have been theoretically designed and numerically simulated to realize single-mode transmission. The propagation loss of a 4-µm-wide straight waveguide was measured as 0.15 dB/cm. The insertion loss of the device was directly measured to be about 5.5 dB. The rise and fall times of the device applied 100 Hz square-wave voltage were obtained as 1.068 and 1.245 ms, respectively. The switching power was about 9.2 mW, and the extinction ratio was 17.8 dB. The low-loss integrated switch arrays are suitable for realizing large-scale photonic integrated circuits.

18.
Zhongguo Zhong Yao Za Zhi ; 39(4): 669-73, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25204144

RESUMO

The optimum conditions of baicalin hydrolysis into baicalein by immobilized beta-glucosidase in a two-phase system was studied and the yield was observed. A two-phase system comprising of sodium acetate buffer and chloroform was determined by comparing the solubleness of baicalein in different solvents and partition coefficient of baicalein in related aqueous-organic two-phase system. beta-Glucosidase was immobilized by the crosslinking-embedding method using sodium alginate as the carrier The optimum reaction temperature, pH value, Michaelis constant, the thermal stability and pH stability were assayed. By comparing the yield of baicalin hydrolysis into baicalein by immobilized beta-glucosidase in two-phase system, the optimum reaction conditions were determined-the optimum reaction temperature, pH value and time were 50 degrees C, 5.0 and 10 h, respectively. The yield of baicalein was 85.28%. Compare with one-phase system, two-phase system had an advantage in reaction rate and yield.


Assuntos
Medicamentos de Ervas Chinesas/química , Flavanonas/química , Flavonoides/química , beta-Glucosidase/química , Biocatálise , Estabilidade Enzimática , Enzimas Imobilizadas/química , Hidrólise
19.
Int J Biol Macromol ; 264(Pt 1): 130418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412936

RESUMO

The cytoplasm, serving as the primary hub of cellular metabolism, stands as a pivotal cornerstone for the harmonious progression of life. The ideal artificial cell should not only have a biomembrane structure system similar to that of a cell and the function of carrying genetic information, but also should have an intracellular environment. In this pursuit, we employed a method involving the incorporation of glycerol into agarose, resulting in the formation of agarose-glycerol mixed sol (AGs). This dynamic sol exhibited fluidic properties at ambient temperature, closely mimicking the viscosity of authentic cytoplasm. Harnessing the electroformation technique, AGs was encapsulated within liposomes, enabling the efficient creation of artificial cells that closely resembled native cellular dimensions through meticulous parameter adjustments of the alternating current (AC) field. Subsequently, artificial cells harboring AGs were subjected to diverse electrolyte and non-electrolyte solutions, enabling a comprehensive exploration of their deformation phenomena, encompassing both inward and outward budding. This study represents a significant stride forward in addressing one of the most fundamental challenges in the construction of artificial cytoplasm. It is our fervent aspiration that this work shall offer invaluable insights and guidance for future endeavors in the realm of artificial cell construction.


Assuntos
Glicerol , Lipossomos , Sefarose/química , Biomimética , Viscosidade
20.
Food Chem X ; 22: 101401, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38711775

RESUMO

Tea products, such as instant tea, have been shown to improve the aroma of meat products. However, the mechanisms by which tea products enhance meat aroma have not been adequately explained. In this study, we analyzed the impact of instant tea on the aroma of duck meat. Our results showed that treatment with instant tea led to increases in floral, baked, and grassy notes while reducing fishy and fatty notes. Several alcohols, aldehydes, ketones, indole and dihydroactinidiolide exhibited significantly increased OAVs. Conversely, certain saturated aldehydes, unsaturated aldehydes and alcohols displayed significantly decreased OAVs. The enhanced floral, baked and grassy notes were attributed to volatile compounds present in instant tea. The reduction in fishy and fatty notes was linked to polyphenols in instant tea interacting with nonanal, undecanal, (E)-2-octenal, (E)-2-nonenal, (E)-2-decenal, and 2,4-decadienal through hydrophobic interactions and electronic effects. This study enhances our understanding of how tea products improve meat aromas.

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