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Fluorescence sensing and imaging techniques are being widely studied for detecting carbon monoxide (CO) in living organisms due to their speed, sensitivity, and ease of use to biological systems. Most fluorescent probes used for this purpose are based on heavy metal ions like Pd, with a few using elements like Ru, Rh, Ir, Os, Tb, and Eu. However, these metals can be expensive and toxic to cells. There is a need for more affordable and biologically safe fluorescent probes for CO detection. Drawing inspiration from the robust affinity exhibited by heme iron toward CO, in this work, a rhodamine derivative called RBF was developed for imaging CO in living cells by binding to Fe(III) and could be used for CO sensing. A Fe(III)-based fluorescent probe for CO imaging in living cells offers advantages of cost effectiveness, low toxicity, and ease of use. The fluorescence detection using the RBF-Fe system showed a direct correlation with increasing levels of CORM-3 (LOD = 146 nM) or the exposure time of CO gas, displaying reduced fluorescence. A CO test paper based on RBF-Fe was created for simple on-site CO detection, where fluorescence would diminish in response to CO exposure, allowing rapid (2 min) visual identification. Imaging of CO in living cells was successfully conducted using the probe system, showing a decrease in fluorescence intensity as CORM-3 concentrations increased, indicating its effectiveness in monitoring CO levels accurately within living cells.
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Monóxido de Carbono , Compostos Férricos , Corantes Fluorescentes , Monóxido de Carbono/análise , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Compostos Férricos/química , Compostos Férricos/análise , Imagem Óptica , Rodaminas/química , Células HeLaRESUMO
Novel high-performance fluorescent approaches have always significant demand for room-temperature detection of carbon monoxide (CO), which is highly toxic even at low concentration levels and is not easy to recognize due to its colorless and odorless nature. In this paper, we constructed a palladium-mediated fluorescence turn-on sensing platform (TPANN-Pd) for the recognition of CO at room temperature, revealing simultaneously quick response speed (<30 s), excellent selectivity, superior sensitivity, and low detection limit (â¼160 nM for CORM-3, â¼1.7 ppb for CO vapor). Moreover, rapid detection and efficient removal (24%) from the air by naked-eye vision has been successfully realized based on TPANN-Pd supramolecular gels. Furthermore, the developed sensing platform was elucidated with low cytotoxicity and high cellular uptake, and it was successfully applied to CO imaging in living cells, providing real-time monitoring of potential CO-involved reactions in biological systems.
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Monóxido de Carbono , Paládio , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidadeRESUMO
Constructing polycyclic aromatics-based, highly emissive fluorophores with good solubility and tunable aggregated structures and properties is of great importance for film fabrication, solution processing, and relevant functionality studies. Herein, we describe a general strategy to endow conventional organic fluorophores with enhanced solubility and modulated fluorescent properties via their incorporation into coordination-driven self-assembled metallacycles. A widely used fluorophore, pyrene, was decorated with two pyridyl groups to yield functionalized pyrene 4. Mixing 4 with three aromatic dicarboxylates with different lengths and a 90° Pt(II) metal acceptor in a 2:2:4 stoichiometric ratio resulted in the formation of three metallacycles, 1, 2, and 3. The metallacycles display good solubility in polar organic solvents, highly aggregation-dependent fluorescence, and size-dependent emissions at higher concentrations. Moreover, metallacycle 2-based, silica-gel-supported film as fabricated not only is more emissive than the ligand 4-based one but also displays much improved sensing properties for amines in the vapor state, as demonstrated by significantly increased response speed and decreased recovery time. The enhanced solubility, unique fluorescence behavior, and multi-factor modulation character show that coordination-driven self-assembly can be utilized for the development of new fluorophores through simple modification of conventional fluorophores. The fluorophores synthesized this way possess not only complex topological structures but also good modularity and tunability in fluorescence behavior, which are important for grafting multi-stage energy-transfer systems necessary for the development of high-performance sensing materials.
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Aminas/análise , Aminas/química , Pirenos/química , Espectrometria de Fluorescência/instrumentação , Modelos Moleculares , Conformação Molecular , Processos FotoquímicosRESUMO
Development of artificial complex molecular systems is of great importance in understanding complexity in natural processes and for achieving new functionalities. One of the strategies is to create them via optimized utilization of noncovalent interactions and dynamic covalent bonds. We report here on a new complex molecular system, which was constructed by integrating the multiple interactions containing a dynamic covalent interaction between 1,2-diol and boronic acid, a coordination interaction between the silver ion and pyridyl, and an easy accessible reaction between secondary amine and formaldehyde. By employing the three dynamic interactions, a pyrene (Py) labeled fluorophore, PPB, was designed and synthesized. The compound reacts with fructose (F), a monosaccharide, in aqueous phase and produces a fluorescent adduct, PPB-F, which can be further used as a sensing platform for formaldehyde (FA) and the silver ion. The respective dynamic interactions are accompanied with color changes due to the reversible switching between Py-monomer emission and excimer emission. The respective experimental detection limits (DLs) for the three analytes are much lower than 0.2 mM, 0.1 mM, and 2.5 µM, respectively. The presence of relevant compounds or ions shows little effect upon the sensing. No doubt, the results as presented show that the integration of supramolecular interactions including dynamic covalent bonds can be employed as a general strategy to develop new functional molecular systems or materials.
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In this article our attempts to tune the color of luminescence within a new class of aggregation-induced emission (AIE) active tellurophenes is reported along with computational details that include spin-orbit coupling effects so as to better understand the nature of emission in the phosphorescent tellurophene (B-Te-6-B). Despite not meeting some of the initial synthetic targets, the emission within a borylated tellurophene can be altered with the addition of an N-heterocyclic carbene.
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BACKGROUND: This study aimed to investigate potential miRNAs and genes associated with the prognosis of hepatocellular carcinoma (HCC). METHODS: Weighted co-expression network analysis was utilized to analyze the mRNA and miRNA sequencing data of HCC from TCGA (The Cancer Genome Atlas) database. Significant network modules were identified, and then functions of genes in the gene network modules and target genes of miRNAs in the miRNA network modules were explored. Additionally, correlations between network modules and prognostic factors of HCC were analyzed. RESULTS: In total, 10 mRNA network modules were identified, three of which were significantly related to tumor stage, NAFLD (non-alcoholic fatty liver disease) and patient age. Four miRNA network modules were identified, of which one was associated with tumor stage. Targets of hsa-miR-363-5p were found distributed in the gene network modules, such as RGPD5, RGPD6, ZNF445 and ZNF780B. Kaplan-Meier test revealed that low expression of hsa-miR-363-5p was associated with better overall survival of HCC patients. CONCLUSION: hsa-miR-363-5p may be a potential prognostic marker for HCC.
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Carcinoma Hepatocelular/genética , Redes Reguladoras de Genes/genética , Neoplasias Hepáticas/genética , MicroRNAs/análise , RNA Mensageiro/análise , Carcinoma Hepatocelular/patologia , Bases de Dados Genéticas , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Estadiamento de Neoplasias , Hepatopatia Gordurosa não Alcoólica/genética , PrognósticoRESUMO
Fast, sensitive and selective detection of diamines in the vapor phase is of pivotal importance for air and food quality monitoring. In this work, an electron-poor fluorophore, perylene bisimide (PBI), was modified with hydrophilic residues at its bay positions, resulting in an amphiphilic derivative, PEBBO. Photophysical studies revealed that the compound shows a strong aggregation tendency in various solvents, but the aggregates could be highly fluorescent provided suitable solvents are used. Accordingly, a fluorescent film was constructed via utilization of the well-known Langmuir-Blodgett technique. Sensing performance studies revealed that the film as prepared is sensitive and selective to the presence of diamines in air. Specifically, (1) the experimental detection limit is lower than 0.016 g m-3 and the linear range of the analysis extends from 0.33 g m-3 to 8.20 g m-3 when ethylenediamine was adopted as an example analyte; (2) the presence of other amines and solvents shows little effect upon detection; (3) the response time is less than 5 s. Considering the importance of diamine sensing, the convenience of fluorescence techniques and the superiorities of the film and method as developed, it is believed that the present work is of great importance for promoting technical progress in diamine sensing.
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BACKGROUND: In patients with persistent upper airway inflammation, the number of forkhead box protein 3 (Foxp3)(+) regulatory T (Treg) cells is reduced, but the regulation of Foxp3 expression in Treg cells is poorly understood. OBJECTIVE: We investigated the interaction between suppressor of cytokine signaling 3 (SOCS3) and Foxp3 expression in the airway mucosa. METHODS: Expression of SOCS3 and Foxp3 was measured in tissue from patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and control tissue. Coexpression of SOCS3 and Foxp3 was evaluated in PBMCs and in tissue from patients with CRSwNP. We also switched off and overexpressed SOCS3 in tissue from patients with CRSwNP and in pancreatic carcinoma epithelial-like cell line (PANC-1) cells and examined the effect on Foxp3 expression. RESULTS: SOCS3 gene and protein expression was upregulated in inflammatory cells in airway mucosa, whereas Foxp3 gene and protein expression was downregulated. Mucosal Treg cells coexpressed both proteins. Switching off the expression of SOCS3 in human airway mucosa resulted in Foxp3 upregulation, whereas inducing it in PANC-1 cells led to Foxp3 downregulation. We also found that phosphorylation of signal transducer and activator of transcription (STAT) 3 was decreased in inflamed mucosa, and we hypothesized that SOCS3 was responsible. Phosphorylation of STAT3 increased on silencing SOCS3 expression in inflamed mucosa and decreased on SOCS3 plasmid transfection in PANC-1 cells. CONCLUSION: For the first time, we demonstrate that SOCS3 and Foxp3 are coexpressed in Treg cells in human nasal mucosa and that SOCS3 negatively regulates Foxp3 expression in human airway mucosa, possibly through phosphorylation of STAT3. Hence SOCS3 could be a potential target for restoring Foxp3 expression in Treg cells in patients with persistent mucosal inflammation.
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Fatores de Transcrição Forkhead/metabolismo , Pólipos Nasais/imunologia , Rinite/imunologia , Sinusite/imunologia , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Proteínas de Transporte , Linhagem Celular Tumoral , Doença Crônica , Feminino , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/imunologia , Fosforilação , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Transgenes/genética , Adulto JovemRESUMO
The excessive use of quinolones (QNs) has seriously threatened human health. In this study, a novel functionalized magnetic covalent organic framework Fe3O4@SiO2@Ah-COF was fabricated with biphenyl-3,3',5,5'-tetracarbaldehyde and hydrazine hydrate (85%) as monomers and was used as a magnetic solid-phase extraction (MSPE) absorbent for the determination of 24 QNs in water and egg samples through ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The extraction parameters of MSPE were optimized, including pH, adsorbent dosage, adsorption time, and eluent type. An effective and rapid detection method was then established, which showed good linearity (R2 ≥ 0.9990), low limits of detection (0.003-0.036 µg L-1) and low limits of quantitation (0.008-0.110 µg L-1) for QNs. The good recoveries of 24 QNs in water and egg samples were in the range of 70.3-106.1% and 70.4-119.7%, respectively, with relative standard deviations lower than 10% (n = 5). As a result, Fe3O4@SiO2@Ah-COF is a promising magnetic adsorbent, and the established method was successfully applied for the determination of 24 QNs in water and egg samples.
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BACKGROUND: To evaluate the effect of perioperative esketamine administration on postpartum depression in pregnant women undergoing cesarean section. METHODS: Data sources was PubMed, Embase, Web of Science, and Cochrane Library from inception to February 1, 2024. Randomized controlled trials in pregnant women undergoing cesarean section were selected and compared to the use of esketamine in the perioperative period. The primary outcome measure was the incidence of postpartum maternal depression. Preferred reporting items for systematic reviews and meta-analyses were used. Data pooled by random-effects models are presented as risk ratios (RR) (95% confidence intervals, 95% CI) or mean differences (95% CI). This review was registered in PROSPERO (ID: CRD42023431197). RESULTS: We included 8 studies with a total of 1655 participants. The quality of the studies was rated high or unclear. Seven studies involving 1485 participants reported the incidence of postpartum depression. Compared with pregnant women undergoing cesarean section without the use of esketamine, those using esketamine in the perioperative period showed a 48% decreased risk of developing postpartum depression (RR: 0.52, 95% CI: 0.35-0.79) and a 1.43-point reduction in EPDS (Edinburgh Postnatal Depression Scale) (mean difference: -1.43, 95% CI: -2.32 to -0.54). For immediate intraoperative adverse reactions, the application of esketamine caused maternal nausea and vomiting (RR: 2.16, 95% CI: 1.22-3.81), dizziness (RR: 6.11, 95% CI: 1.49-24.98), and hallucinations (RR: 6.83, 95% CI: 1.57-29.68) compared to no esketamine use. CONCLUSIONS: Perioperative use of esketamine in pregnant women undergoing cesarean section may reduce postpartum depression and increase intraoperative adverse reactions, but has no significant effect on postoperative adverse reactions.
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Cesárea , Depressão Pós-Parto , Ketamina , Humanos , Ketamina/administração & dosagem , Ketamina/uso terapêutico , Feminino , Cesárea/efeitos adversos , Gravidez , Depressão Pós-Parto/prevenção & controle , Depressão Pós-Parto/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Assistência Perioperatória/métodosRESUMO
The presence of minute quantities of water in organic solvents can affect the progress of many reactions and cause unnecessary losses and even safety accidents in the chemical industry, especially in the productions process of organic fine chemicals. Therefore, it is necessary to carry out high-performance strategies for trace water detections in commonly used organic solvents. In this work, a fluorescent sensing system based on competitive binding of protons has been developed, demonstrating remarkable responses by UV-vis absorption and fluorescence two-modes toward a trace amount of water in organic solvents including 1,4-dioxane (Diox), tetrahydrofuran (THF), acetonitrile (MeCN), acetone (ACE), dimethylsulfoxide (DMSO) and mixed organic solvents (THF: MeCN=1: 1). The key component of the sensing system is a newly designed fluorophore NBD-PMA, which can be deprotonated to form a dynamic non-luminescent adduct, namely NBD-PMA-F, by an organic fluoride salt tetrabutylammonium fluoride (TBAF). NBD-PMA-F can be reprotonated via using trace water, exhibiting fluorescence turn on of the system. The as-prepared sensing system shows superior sensitivity, low detection limits (v/v, 0.0007 %), quick response speed (≤1.2 s) and good reversibility. Moreover, naked-eye visual rapid detection has also been successfully realized at ambient temperature, which demonstrated their practical applications value for trace water determinations.
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Organic light-emitting diodes (OLEDs) that can simultaneously achieve narrowband emission, high efficiency, and circularly polarized luminescence remain a formidable challenge. In this study, a simple strategy is developed to address this challenge. A chiral exciplex-forming co-host is first designed by employing a chiral donor and an achiral acceptor molecule. The chiral exciplex host enables an achiral green multiple-resonance thermally activated delayed fluorescence emitter to achieve high-performance circularly polarized electroluminescence (CP-EL) with a high external quantum efficiency of 33.2%, large electroluminescence dissymmetry factor of 2.8 × 10-3 , and a small full-width at half-maximum of 42 nm. This work provides a general approach for realizing CP-EL using easily available achiral emitters and can significantly extend the scope of circularly polarized OLEDs.
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PURPOSE: Interleukin 23 (IL-23) affects tumor growth by regulating Th cells and plays a vital role in immunosuppression in tumor tissues. However, whether tumor cells are IL-23R positive or whether IL-23 has the potential to influence the growth of cancer cells directly remains unclear. The aim of this study was to clarify the molecular expression patterns of IL-23, IL-23R, and Forkhead box P3 (FOXP3) in normal tissues adjacent to cancer, in intestinal polyps (IP), and in colorectal carcinoma (CRC), and to infer the relationship between the expression patterns of these three molecules and the progress of intestinal tumors from adenomatous polyps to colorectal cancer. METHODS: The levels of IL-23A, IL-23R, and FOXP3 were evaluated in normal tissues adjacent to cancer (NT, n = 13), IP (n = 26), and CRC (n = 13) using real-time PCR, ELISA, western blotting, immunohistochemistry, and immunocytochemistry. RESULTS: The expression of IL-23 and FOXP3 increased progressively from NT through to CRC. Immunohistochemistry staining showed that IL-23R was highly positive in carcinoma cells of the CRC group, whereas it was partially positive in cells of other groups. In addition, the human CRC cell line SW-480 exhibited weak IL-23R immunocytochemical positivity. CONCLUSIONS: We propose that the IL-23/IL-23R pathway is a potential route to facilitate the malignant progression of cancers. The relationship between IL-23 and FOXP3 in the microenvironment of carcinoma led us to deduce that these two molecules may interact with each other. Although the exact mechanism underlying this interaction remains a mystery, we are convinced that these two molecules are relevant in cancer progression and that IL-23 could be a potential target for cancer immunotherapy.
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Pólipos Adenomatosos/patologia , Neoplasias Colorretais/patologia , Progressão da Doença , Subunidade p19 da Interleucina-23/metabolismo , Receptores de Interleucina/metabolismo , Pólipos Adenomatosos/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Subunidade p19 da Interleucina-23/genética , Receptores de Interleucina/genética , Transcrição GênicaRESUMO
BACKGROUND: It is widely accepted that T helper 2 (Th2) cells, Th17 cells and their cytokines orchestrate the feature of asthma. However, most of studies on asthma mechanisms use a single allergen challenge model. Actually, humans are concurrently exposed to various allergens, and the mechanism of asthma with complex allergen exposure is less well defined. To explore whether the mechanism would be altered if asthma patients are re-exposed to another allergen, we exposed the chicken egg albumin (OVA) induced-asthmatic mice to house dust mite (HDM). MATERIAL/METHODS: HE staining was used to analyze pathologic variation in lung tissue of mice in each sub-group: control group, HDM alone group, OVA alone group and OVA+HDM group. Th1, Th2 and Th17 associated gene mRNA expressions were detected by quantitative PCR; associated cytokines were determined by ELISA or immunohistochemistry. RESULTS: The severe of inflammatory cell infiltration, the augmentation of Th17 and Th2 related gene mRNA expressions and the increase of Th17 associated cytokines expression were shown in OVA+HDM group in comparison with OVA alone group. However, Th2 related cytokines were increased with no significant difference in OVA+HDM group compared with OVA alone group. CONCLUSIONS: We have found that Th17 response is connected with inflammation in the OVA-induced asthmatic mice exposed to HDM. When OVA-induced asthmatic mice are re-exposed to HDM, the pathomechanism is different from OVA alone exposure. HDM, indoor allergen, may be an important interferential factor for asthma therapy. It will give an important direction in the development of future asthma therapy.
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Asma/imunologia , Asma/parasitologia , Pyroglyphidae/imunologia , Células Th17/imunologia , Alérgenos/imunologia , Animais , Asma/sangue , Asma/patologia , Líquido da Lavagem Broncoalveolar , Citocinas/biossíntese , Citocinas/sangue , Citocinas/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Pulmão/parasitologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Th2/imunologiaRESUMO
Zinc finger proteins have been implicated as transcription factors in the differentiation and development of cells and tissues in higher organisms. The classical C2H2 zinc finger motif is one main type of motif of zinc finger proteins. Our previous studies have shown that Zfp637, which comprises six consecutively typical and one atypical C2H2 zinc finger motifs, is highly expressed in undifferentiated or poorly differentiated cell lines, but is moderately or slightly expressed in normal tissues. We have also demonstrated that Zfp637 can promote cell proliferation. However, its role in the regulation of cell differentiation remains unknown. We report here that endogenous Zfp637 as well as mTERT is expressed in proliferating C2C12 myoblasts and that their expression is downregulated during myogenic differentiation. Constitutive expression of Zfp637 in C2C12 myoblasts increased mTERT expression and telomerase activity, and promoted the progression of the cell cycle and cell proliferation. By contrast, endogenous repression of Zfp637 expression by RNA interference downregulated the mTERT gene and the activity of telomerase, and markedly reduced cell proliferation. Overexpression of Zfp637 also inhibited the expression of myogenic differentiation-specific genes such as MyoD and myogenin, and prevented C2C12 myoblast differentiation. Our results suggest that Zfp637 inhibits muscle differentiation through a defect in the cell cycle exit by potentially regulating mTERT expression in C2C12 myoblasts. This may provide a new research line for studying muscle differentiation.
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Diferenciação Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Músculo Esquelético/citologia , Dedos de Zinco , Animais , Sequência de Bases , Western Blotting , Linhagem Celular , Proliferação de Células , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Camundongos , Músculo Esquelético/enzimologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telomerase/metabolismoRESUMO
Structure-function relationships of starch isolated from eight cultivars of foxtail millets grown in China were investigated. The starch granules were polygonal with diameters between 5⯵m and 10⯵m. The amylose content ranged from 16.8% to 26.8%, and the relative crystallinity and the full width at half maximum (FWHM) of the Raman band at 480â¯cm-1 varying between 33.2% and 36.4% and 15.72 to 15.91, respectively. There were only small differences in amylopectin chain length distribution of the eight foxtail millet starches. Significant differences were noted in swelling power, gelatinization, pasting, gel textural properties of starches, but not in vitro enzymic digestibility. Correlation analysis results showed that amylose content and chain length distribution of amylopectin were more important determinants of functional properties of starch than the structural order of the starch granules.
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Amilose/análise , Setaria (Planta)/química , Amido/química , Amilopectina/química , China , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
OBJECTIVE: To construct the eukaryotic expression plasmid and establish stably transfected cell line, which contained the code gene of zinc finger protein637 (Zfp637), and to observe the effect of Zfp637 gene to the proliferation of tumor cells. METHODS: The Zfp637 DNA was amplified from the template of normal spleen tissue cDNA and cloned into the eukaryotic expression vector pEGFP-C3. The recombinant plasmid, named as pEGFP-Zfp637, was determined by restriction enzyme and sequencing analyses. Next the pEGFP-Zfp637 recombinant plasmid was transferred into mouse breast carcinoma EMT6 cells with lipofectamine 2000, and the stably transfected cells were selected by G418 (named Zfp637-EMT6). The growth condition of cells was observed, and subcellular localization of Zfp637 gene was located by fluorescence microscope at the same time. The Zfp637 mRNA expression in the transfected cells was detected by RT-PCR, and the proliferation of such cells was measured by MTT. RESULTS: The analysis confirmed that the recombinant pEGFP-Zfp637 contained the Zfp637 full-length cDNA. The Zfp637 mRNA was over-expressed stably in Zfp637-EMT6. The growth of Zfp637-EMT6 was increased obviously when compared with the negative control group and blank group. CONCLUSION: The recombinant pEGFP-Zfp637 has been constructed successfully, and the expression of the Zfp637 gene can promote the proliferation of cells. This recombinant eukaryotic expression plasmid can be used in advanced studies in the biological effects of Zfp637 and anti-tumor gene therapy.
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Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Proteínas Repressoras/genética , Dedos de Zinco/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Terapia Genética , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Repressoras/biossíntese , TransfecçãoRESUMO
A reversible mechanochromic luminescent material based on a simple tetrahedral monoboron complex (B-1) is described. Interestingly, in addition to amorphous powders (P), the compound could exist in three unique crystal states (A, B, and C), showing efficient green-to-red luminescent colors, which is a result of wane and wax of dual emissions of the compound. Surprisingly, one of the emissions increases significantly with increasing temperature, fully offsetting the quenching effect of temperature-assisted internal conversion process. The four states are fully interconvertible through grinding and heating, allowing color writing/painting with a single ink.
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BTEX (benzene, toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene) represents a group of volatile organic compounds (VOCs) and constitutes a great threat to human health. However, sensitive, selective, and speedy detection of them on-site and in the vapor phase remains a challenge for years. Herein, we report a film-based fluorescent approach and a conceptual sensor, which shows unprecedented sensitivity, speed, and reversibility to the aromatic hydrocarbons in the vapor phase. In the studies, pentiptycene was employed to produce a nonplanar perylene bisimide (PBI) derivative, P-PBI. The compound was further utilized to fabricate the film. The novelty of the design is the combination of capillary condensation and solvent effect, which is expected to enrich the analytes from vapor phase and shows outputs at the same time. Importantly, the film permits instant response (â¼3 s) and real-time identification (<1 min) of benzene and toluene from other aromatic hydrocarbons. The experimental detection limits (DLs) of the six analytes are lower than 9.2, 2.7, 1.9, 0.2, 0.4, and 0.4 ppm, which with the exception of benzene, are significantly lower than the NIOSH recommended long-term exposure limits. More importantly, the film is photochemically stable, and more than 300 repetitive tests showed no observable bleaching. In addition, the sensing is fully reversible. The superior performance of the film device is in support of the assumption that the combination of capillary condensation and solvation effect would constitute an effective way to design high-performance fluorescent films, especially for challenging chemical inert and photoelectronically inactive VOCs.
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This work reports a conceptual sensor array for the highly discriminative analysis of 20 clinically and environmentally relevant volatile small organic molecules (VSOMs), including saturated alkanes and common solvents, in the air at room temperature. For the construction of the sensor array, a four coordinated, non-planar mono-boron complex and four relevant polymers are synthesized. Based on the polymers and the use of different substrates, 8 fluorescent films have been fabricated. Integration of the film-based sensors results in the sensor array, which demonstrates unprecedented discriminating capability toward the VSOMs. Moreover, for the signal molecule of lung cancer, n-pentane, the response time is less than 1 s, the experimental detection limit is lower than 3.7 ppm, and after repeating the tests over 50 times no observable degradation was observed. The superior sensing performance is partially ascribed to the tetrahedral structure of the boron centers in the polymers as it may produce molecular channels in the films, which are a necessity for fast and reversible sensing. In addition, the polarity of the micro-channels may endow the films with additional selectivity towards the analytes. The design as demonstrated provides an effective strategy to improve the sensing performance of fluorescent films to very challenging analytes, such as saturated alkanes.