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Lithium carbon dioxide (Li-CO2) batteries, noted for their high discharge voltage of approximately 2.8 V and substantial theoretical specific energy of 1876 Wh kg-1, represent a promising avenue for new energy sources and CO2 emission reduction. However, the practical application of these batteries faces significant hurdles, particularly at high current densities and over extended cycle lives, due to their complex reaction mechanisms and slow kinetics. This paper delves into the recent advancements in cathode catalysts for Li-CO2 batteries, with a specific focus on the designing philosophy from composition, geometry, and homogeneity of the catalysts to the proper test conditions and real-world application. It surveys the possible catalytic mechanisms, giving readers a brief introduction of how the energy is stored and released as well as the critical exploration of the relationship between material properties and performances. Specifically, optimization and standardization of test conditions for Li-CO2 battery research is highlighted to enhance data comparability, which is also critical to facilitate the practical application of Li-CO2 batteries. This review aims to bring up inspiration from previous work to advance the design of more effective and sustainable cathode catalysts, tailored to meet the practical demands of Li-CO2 batteries.
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A nylon-like polyester tire cord, which combined the characteristics of nylon and polyester tire cords, was designed as the carcass reinforcement material used to meet the increasing demands of the tire industry for performance and impact on the environment. Tires' carcass construction plays a crucial role in affecting handling performance and ride comfort. Small changes in the carcass component can lead to significant improvements in the total tire/vehicle performance. This study evaluated the performance of nylon-like polyester and nylon 6 motorcycle tires. The results showed that the nylon-like polyester tire passed all indoor tests, and post-cure inflation (PCI) could be eliminated, resulting in energy and cost savings. The rolling resistance coefficient of the nylon-like polyester tire was reduced by 6.8% compared to that of the nylon 6 control tire, which could save fuel and have a positive impact on the environment. Nylon-like polyester tire cord extracted from the experimental tire possessed a higher modulus compared to that of nylon 6 tire cord, which could lead to better handling and ride comfort performance. Morphological pictures showed that both nylon-like polyester and nylon 6 cords extracted from tires had a good rubber coverage and comparable adhesion properties.
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A tert-butyldiphenylsilyl-containing polyimide (PI-OSi) has been established as a colorimetric and ratiometric chemosensor for rapid detecting fluoride ions (F-). The UV-vis absorbance ratio value (A322/A288) of PI-OSi in a DMF solution displays a wide linear range change to F- concentrations with a detection limit (DL) value of 2.13 µM. Additionally, adding incremental amounts of F- to a DMF solution of PI-OSi shows an immediate color change to yellow and finally to green from colorless. More interestingly, the resulting PI-OSi plus F- system (PI-OSi·F) could detect trace water in DMF. The A292/A322 value of PI-OSi·F almost linearly increases with low water content, which suggests convenient quantitative sensing of trace water content in DMF. The DL value of PI-OSi·F for sensing water in DMF is determined to be 0.00149% (v/v). The solution color of PI-OSi·F returns to colorless when the water content increases, indicating that PI-OSi·F can conveniently estimate water content in DMF by naked-eye detection. The detection mechanisms confirmed by an 1H NMR study and a DFT calculation involve a F--induced desilylation reaction of PI-OSi to form phenolate anion followed by protonation with trace water. Finally, PI-OSi film was fabricated for the colorimetric detection of F- and water in CH3CN.
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Multistimuli-responsive fluorescent materials have garnered great research interest benefited from their practical applications. Two twisted-structure compounds containing tetraphenylethylene (TPE) as the aggregation-induced emission (AIE) group and a pyridine unit as the acid reaction site to obtain new multistimuli-responsive fluorescent compounds (namely, TPECNPy: TPECNPy-2 and TPECNPy-3) were successfully synthesized through a one-step Knoevenagel condensation reaction. The multiple-stimuli response process of TPECNPy was investigated by means of photoluminescence (PL) spectra and emission colour. The results showed that both TPECNPy compounds with excellent AIE abilities displayed reversible emission wavelength and colour changes in response to multiple external stimuli, including grinding-fuming by CH2 Cl2 or annealing and HCl-NH3 vapour fuming. More importantly, fluorescent nanofibre films were prepared by electrospinning a solution of TPECNPy mixed with cellulose acetate (CA), and these exhibited reversible acid-induced discolouration, even with only 1 wt% TPECNPy. The results of this study may inspire strategies for designing multistimuli-responsive materials and preparing fluorescent sensing nanofibre films.
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Nanofibras , Fluorescência , Corantes Fluorescentes/químicaRESUMO
Organic perovskites are promising optoelectronic semiconductor materials with photoelectric applications. It is known that the luminescence of perovskites is highly sensitive to hydron molecules due to its low moisture resistance of crystal structure, indicating its potential application on humidity-sensing. Herein, a novel perovskite-based compound (PBC) with minimal defects was developed to promote the photoluminescence performance via optimization of the drying method and precursor constitutions. Perovskite materials with good structural integrity and enhanced fluorescence performance up to four times were obtained from supercritical drying. Moreover, the hydrophilic polymer matrix, polyethylene oxide (PEO), was added to obtain a composite of perovskite/PEO (PPC), introducing enhanced humidity sensitivity and solution processibility. These perovskite/PEO composites also exhibited long-term stability and manifold cycles of sensitivity to humidity owing to perovskite encapsulation by PEO. In addition, this precursor solution of perovskite-based composites could be fancily processed by multiple methods, including printing and handwriting, which demonstrates the potential and broaden the applications in architecture decoration, logos, trademarks, and double encryption of anti-fake combined with humidity.
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Three fluorene-based polyimides with silyl ether groups (Si-PIs) were successfully synthesized by a simple and efficient silicon etherification reaction of hydroxyl-containing polyimides (OH-PIs) and tert-butylchlorodiphenylsilane (TBDPSCl), and their structures were confirmed by 1H NMR and IR spectra. The bulky nonpolar tert-butyldiphenylsilyl (TBDPS) side groups in the modified PI unit instead of the strong electron donor -OH group is conducive to decreasing electronic conjugation and charge transfer (CT) interaction along the PI chain. Accordingly, the optical, dielectric, and solubility properties of the modified Si-PI films are simultaneously improved compared with the precursor OH-PI films. The modified Si-PI films demonstrate a meaningful enhancement in the transmittances at a wavelength of 400 nm (T 400 ) to 74-81% from 42 to 55% of OH-PI films and the regeneration of fluorescence characteristics. The dielectric constant and loss of Si-PI films are also obviously reduced to 2.63-2.75 and 0.0024-0.0091 at 1 kHz from 4.19 to 4.78 and 0.0173-0.0295 of OH-PI films, respectively, due to substituted with the bulky nonpolar TBDPS groups to increase the free volume and hydrophobicity of Si-PI films. The solubility of Si-PIs in low- or nonpolar solvents (such as CHCl3, CH2Cl2, acetone, and toluene) is significantly improved. Furthermore, Si-PI films still maintain relatively good thermal properties with the 5% weight loss temperature (T 5% ) in the range 470-491 °C under a nitrogen atmosphere and the glass transition temperature (T g ) in the range 245-308 °C.
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Fluorescent sensors that respond to environmental conditions (temperature, pressure, and pH) have attracted widespread attention in recent years. Generally, traditional solid-state fluorescent materials tend to suffer from aggregation-induced quenching (ACQ) and difficulty of film forming, limiting their extensive applications. Therefore, researchers are focusing more and more attention on fluorescent sensors with aggregation-induced emission (AIE) effects. Herein, the article reports an AIE molecule (TPEBZMZ) containing tetraphenylethylene (TPE) and benzimidazole fragments. The fluorescence properties of TPEBZMZ in solution and aggregation states have been investigated, and the luminescence performance and aggregation structures of solid-state TPEBZMZ after force and acid treatments have been explored. The results show obvious AIE and fluorescent sensing properties of TPEBZMZ, presenting force- and acid-induced discolorations. Moreover, the TPEBZMZ-based fluorescent nanofibrous film is fabricated by electrospinning the solution of TPEBZMZ blended with polylactic acid (PLA), which shows a good nanofiber film structure and exhibits reversible acid-induced discoloration property, even with only 0.5 wt% TPEBZMZ. This work provides a simple strategy to achieve stimulus-responsive fluorescent film.
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Alzheimer's disease (AD) is a common neurodegenerative disease. Aß plays an important role in the pathogenesis of AD. Sodium butyrate (NaB) is a short-chain fatty acid salt that exerts neuroprotective effects such as anti-inflammatory, antioxidant, antiapoptotic, and cognitive improvement in central nervous system diseases. The aim of this study is to research the protective effects of NaB on neurons against Aß toxicity and to uncover the underlying mechanisms. The results showed that 2 mM NaB had a significant improvement effect on Aß-induced N2a cell injury, by increasing cell viability and reducing ROS to reduce injury. In addition, by acting on the GPR109A receptor, NaB regulates the expression of AD-related genes such as APP, NEP, and BDNF. Therefore, NaB protects N2a cells from Aß-induced cell damage through activating GPR109A, which provides an innovative idea for the treatment of AD.
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Peptídeos beta-Amiloides/toxicidade , Ácido Butírico/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Fator Neurotrófico Derivado do Encéfalo/análise , Sobrevivência Celular/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Receptores Acoplados a Proteínas G/fisiologia , Células Tumorais CultivadasRESUMO
Two new hydroxyl-containing polyimides (PIs) with excellent comprehensive performances were designed and synthesized. After PIs react with fluoride ion (F-), the resulting polyimide-fluoride complexes (PI-1·F and PI-2·F) are exploited as ratiometric and colorimetric sensors for detecting trace water in DMSO/DMF with high sensitivity. Both sensors PI-1·F and PI-2·F exhibit a good naked-eye visual detection as well as an excellent linear relationship between the UV-vis absorbance ratio and the low water content in DMSO/DMF, which constitutes a quantitative method for determining water content in DMSO/DMF. The limits of detection (LOD) of sensor PI-1·F for water in DMSO and DMF are as low as 0.0035% and 0.0031% (v/v), respectively. The sensor PI-2·F shows the higher sensitivity for water detection with extremely low detection limits of 0.00084% and 0.0015% in DMSO and DMF, respectively. Furthermore, PI films have been directly used for the visual sensing of water in acetonitrile, acetone and ethanol, which provides an effective way for fabricating high-performance film-based water sensor devices.
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Accumulation of amyloid ß (Aß) peptide, inflammation, and oxidative stress contribute to Alzheimer's disease (AD) and trigger complex pathogenesis. The ketone body ß-hydroxybutyrate (BHBA) is an endogenous metabolic intermediate that protects against stroke and neurodegenerative diseases, but the underlying mechanisms are unclear. The present study aims to elucidate the protective effects of BHBA in the early stage of AD model and investigate the underlying molecular mechanisms. Three-and-half-month-old double-transgenic mice (5XFAD) overexpressing ß-amyloid precursor protein (APP) and presenilin-1 (PS1) were used as the AD model. The 5XFAD mice received 1.5 mmol/kg/d BHBA subcutaneously for 28 days. Morris water maze test, nest construction, and passive avoidance experiments were performed to assess the therapeutic effects on AD prevention in vivo, and brain pathology of 5XFAD mice including amyloid plaque deposition and microglia activation were assessed. Gene expression profiles in the cortexes of 5XFAD- and BHBA-treated 5XFAD mice were performed with high-throughput sequencing and bioinformatic analysis. Mouse HT22 cells were treated with 2 mM BHBA to explore its in vitro protective effects of BHBA on hippocampal neurons against Aß oligomer toxicity, ATP production, ROS generation, and mitochondrial aerobic respiratory function. APP, BACE1, and neprilysin (NEP) expression levels were evaluated in HT22 cells following treatment with BHBA by measuring the presence or absence of G protein-coupled receptor 109A (GPR109A). BHBA improved cognitive function of 5XFAD mice in Morris water maze test, nesting construction and passive avoidance experiments, and attenuated Aß accumulation and microglia overactivation in the brain. BHBA also enhanced mitochondrial respiratory function of hippocampal neurons and protected it from Aß toxicity. The enzymes, APP and NEP were regulated by BHBA via G-protein-coupled receptor 109A (GPR109A). Furthermore, RNA sequencing revealed that BHBA-regulated genes mainly annotated in aging, immune system, nervous system, and neurodegenerative diseases. Our data suggested that BHBA confers protection against the AD-like pathological events in the AD mouse model by targeting multiple aspects of AD and it may become a promising candidate for the prevention and treatment of AD.
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Ácido 3-Hidroxibutírico/farmacologia , Doença de Alzheimer/tratamento farmacológico , Cognição/efeitos dos fármacos , Hipocampo/metabolismo , Neurônios/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipocampo/patologia , Camundongos , Camundongos Transgênicos , Neurônios/patologiaRESUMO
A novel aromatic diamine containing pyridyl side group, 4-pyridine-4,4-bis(3,5-dimethyl-5-aminophenyl)methane (PyDPM), was successfully synthesized via electrophilic substitution reaction. The polyimides (PIs) containing pyridine were obtained via the microwave-assisted one-step polycondensation of the PyDPM with pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 3,3',4,4'-diphenylether tetracarboxylic dianhydride (ODPA) and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA). Contrarily to the reported similar PIs, these PIs exhibit much higher thermal stability or heat resistance, i.e. high glass transition temperatures (T gs) in the range of 358-473°C, and the decomposition temperatures at 5% weight loss over 476°C under nitrogen. They can afford flexible and strong films with tensile strength of 82.1-93.3 MPa, elongation at break of 3.7%-15.2%, and Young's modulus of 3.3-3.8 GPa. Furthermore, The PI films exhibit good optical transparency with the cut-off wavelength at 313-366 nm and transmittance higher than 73% at 450 nm. The excellent thermal and optical transmittance can be attributed to synthesis method and the introduction of pyridine rings and ortho-methyl groups. The inherent viscosities of PIs via one-step method were found to be 0.58-1.12 dl g-1 in DMAc, much higher than those via two-step method. These results indicate these PIs could be potential candidates for optical substrates of organic light emitting diodes (OLEDs).
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Three novel bisbenzimidazole derivatives have been synthesized and developed as dual-functional fluorescent sensors for the rapid and highly selective detection of Ag+ and Fe3+ ions in semi-aqueous medium with distinct spectral response for the first time. The absorption intensity is drastically decreased after the addition of Ag+. Contrarily, it is markedly increased upon the addition of Fe3+. And there is a good linear relation at low concentration of both Ag+ and Fe3+, which provides a quantitative method for their detection. Similarly, the sensors show a distinct fluorescence response towards Ag+ and Fe3+ with a different fluorescence color change under UV light. In addition, no significant changes and interference can be observed with other metal ions. The sensing mechanism studies confirm that the N atom in CN of benzimidazole ring of sensor 4a may bind with Ag+ or Fe3+ ion to form metal complex. And there is only a static quenching process for the 4-Ag+ complex system, but both dynamic and static quenching processes occur in the 4-Fe3+ complex system. Moreover, sensors 4 can steadily work in solution with a wide range of pHâ¯4-13 and rapidly respond to Ag+ and Fe3+ with a response time of 10â¯s. Finally, the sensors have been successfully applied to the visual detection of Ag+ and Fe3+ not only in solution, but also in test paper.
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OBJECTIVE: To investigate the feasibility of proximal tubal occlusion with fibered platinum coils in subfertile women with hydrosalpinx, and to observe the clinical outcomes of subsequent treatment with in vitro fertilization and embryo transfer (IVF-ET). STUDY DESIGN: A prospective study was carried out in a university-affiliated teaching hospital. 56 women with uni- or bilateral hydrosalpinx received fibered platinum coil placement before IVF-ET. The clinical pregnancy rate and live birth rate was evaluated. Data analysis was performed with SPSS version 22.0 (SPSS, Inc., Chicago, IL, USA), using two-sided test, and a p value < 0.05 was considered statistically significant. The study has been registered in the ClinicalTrials. gov with the number of NCT03395301. RESULT(S): Successful placement was achieved in 106 fallopian tubes of 55 patients. The fibered platinum coils induced complete proximal occlusion in 52 out of 55 patients in the following 3-month HSG examination. In the 52 patients, 44 patients received following IVF-ET. The clinical pregnancy rate reached 60.5%(23/38)and live birth rate reached 60.87% (14/23) in patients less than 40 years old. CONCLUSION(S): Fibered platinum coil is a new, safe and valuable device for hysteroscopic tubal proximal occlusion in subfertile women with hydrosalpinx but with laparoscopic contradictions to improve the reproductive outcomes of IVF-ET. Capsule: Fibered platinum coil is a new, safe and valuable device for hysteroscopic tubal proximal occlusion in subfertile women with hydrosalpinx to improve the reproductive outcomes of in vitro fertilization and embryo transfer.
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Doenças das Tubas Uterinas/cirurgia , Fertilização in vitro/estatística & dados numéricos , Procedimentos Cirúrgicos em Ginecologia/instrumentação , Adulto , Doenças das Tubas Uterinas/complicações , Feminino , Humanos , Infertilidade Feminina/etiologia , Gravidez , Taxa de Gravidez , Estudos ProspectivosRESUMO
BACKGROUND/AIMS: Butyric acid plays an important role in maintaining intestinal health. Butyric acid has received special attention as a short-chain fatty acid, but its role in protecting the intestinal barrier is poorly characterized. Butyric acid not only provides energy for epithelial cells but also acts as a histone deacetylase inhibitor; it is also a natural ligand for G protein-coupled receptor 109A (GPR109A). A GPR109A analog was expressed in Sus scrofa and mediated the anti-inflammatory effects of beta-hydroxybutyric acid. This study investigated the effects of butyrate on growth performance, diarrhea symptoms, and tight junction protein levels in 21-day-old weaned piglets. We also studied the mechanism by which butyric acid regulates intestinal permeability. METHODS: Twenty-four piglets that had been weaned at an age of 21 days were divided randomly into 2 equal groups: basal diet group and sodium butyrate + basal diet group. Diarrhea rate, growth performance during 3 weeks of feeding on these diets were observed, the lactulose-mannitol ratio in urine were detected by High Performance Liquid Chromatography, the expression levels of tight junction proteins in the intestinal tract and related signaling molecules, such as GPR109A and Akt, in the colon were examined by quantitative real-time PCR or western blot analyses on day 21. Caco-2 cells were used as a colon cell model and cultured with or without sodium butyrate to assess the expression of tight junction proteins and the activation of related signaling molecules. GPR109A-short hairpin RNA (shRNA) and specific antagonists of Akt and ERK1/2 were used as signaling pathway inhibitors to elucidate the mechanism by which butyric acid regulates the expression of tight junction proteins and the colonic epithelial barrier. RESULTS: The sodium butyrate diet alleviated diarrhea symptoms and decreased intestinal permeability without affecting the growth of early weaned piglets. The expression levels of the tight junction proteins Claudin-3, Occludin, and zonula occludens 1 were up-regulated by sodium butyrate in the colon and Caco-2 cells. GPR109A knockdown using shRNA or blockade of the Akt signaling pathway in Caco-2 cells suppressed sodium butyrate-induced Claudin-3 expression. CONCLUSIONS: Sodium butyrate acts on the Akt signaling pathway to facilitate Claudin-3 expression in the colon in a GPR109A-dependent manner.
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Ácido Butírico/farmacologia , Colo/metabolismo , Diarreia , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores Nicotínicos/biossíntese , Junções Íntimas/metabolismo , Animais , Células CACO-2 , Colo/patologia , Diarreia/tratamento farmacológico , Diarreia/metabolismo , Diarreia/patologia , Humanos , Suínos , Junções Íntimas/patologiaRESUMO
To add the growing literature on baseline of high-risk human papillomavirus (HR-HPV) genotype distribution in cervical intraepithelial neoplasia (CIN) before the widespread using of HPV vaccines in Chinese mainland and to improve risk stratification of HR-HPV-positive women. Retrospectively, the data of age, cervical HPV genotypes, cytology, and pathology were collected from 1166 patients who received loop electrosurgical excision procedure (LEEP). HPV genotypes were analyzed with Flowcytometry Fluorescence Hybridization Method. And then HPV prevalence, HR-HPV genotype distribution and the correlation of HR-HPV genotypes with CIN2+ (CIN2 or severer) were analyzed. The role of multiple HR-HPV types infection with or without HPV16/18 in the pathogenesis of CIN2+ was also analyzed. The 6 most common HR-HPV genotypes were HPV16, 58, 52, 33, 18, and 31 in descending order. Compared to HR-HPV-negative women, HPV16, 33 or 58 positive women had higher risk of CIN2+ (OR = 5.10, 95% CI = 2.68-9.70; OR = 3.09, 95% CI = 1.39-6.84; OR = 3.57, 95% CI = 1.85-6.89, respectively). And women who were infected by multiple HR-HPV types infection with HPV16/18 also had higher risk of CIN2+ (OR = 2.58, 95% CI = 1.35-4.92). However, multiple HR-HPV types infection without HPV16/18 did not increase the risk significantly (P = .08). Compare to bivalent Cervarix® and quadrivalent Gardasil® , HPV prophylactic vaccine targeting HPV31, 33, 52, and 58 might provide women more protection from HPV-induced cervical cancer in China. The women who infected by HPV16, 33, 58, or multiple HR-HPV types with HPV16/18 have higher risk of CIN2+ and need to be paid more attention in screening processes. And the role of multiple HR-HPV types infection without HPV16/18 needs be further identified in more studies.
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BACKGROUND: Semen cryopreservation has been widely applied in assisted reproductive technologies and sperm bank, but it causes considerable impairments on sperm quality. It is necessary to find an evaluation indicator for determining the sperm-freezing tolerance. METHODS: The glycocalyx of good freezability ejaculates was compared with poor freezability ejaculates by lectin microarray. The significant different lectins were validated by flow cytometry (FACS). To analyze the relationship between the potential biomarker and the tolerance of sperm to cryopreservation, 60 samples with different recovery rates were collected and detected the lectin-binding intensity by FACS. The receiver operating characteristic (ROC) curve was analyzed to test the capability of the lectin as a potential biomarker for detecting the sperm freezablility. RESULTS: ABA and DSL were found to develop significant differences between them. Further validation showed that ABA was significantly negative correlated with the sperm recovery rates (r = - 0.618, P < 0.000) and could be a potential biomarker for predicting sperm freezability (AUC = 0.733 ± 0.067, 95% CI 0.601 - 0.865, P < 0.01). CONCLUSION: ABA could be a potential biomarker for predicting sperm freezability. It will help to reduce sperm-freezing recovery tests and improve the efficiency of cryopreservation in human sperm bank.
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New bis-2(5H)-furanone derivatives containing a benzidine core were synthesized via a one-step transition-metal-free reaction of benzidine with 5-substituted 3,4-dihalo-2(5H)-furanones. Their antitumor activities against various tumor cells have been evaluated by MTT assay. Among them, compound 4e exhibits significant inhibitory activity against C6 glioma cells with an IC50 value of 12.1 µm and low toxicity toward HaCaT human normal cells. Studies on the antitumor mechanism reveal that cell cycle arrest at S-phase in C6 cells is induced by compound 4e. Furthermore, investigations with electronic, fluorescence emission and circular dichroism spectra show that compound 4e can significantly interact with C6-DNA. These data indicate that DNA may be one of the potential targets for bis-2(5H)-furanone derivatives as anticancer drugs.
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Antineoplásicos/síntese química , Desenho de Fármacos , Furanos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dicroísmo Circular , DNA/química , DNA/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/metabolismo , Furanos/farmacologia , Humanos , Conformação de Ácido Nucleico , Octanóis/química , Eletricidade Estática , Relação Estrutura-Atividade , Água/químicaRESUMO
An efficient route without metal catalyst has been developed for synthesis of 4-biphenylamino-5-halo-2(5H)-furanones. The antitumor activities against various tumor cells of all the compounds have been evaluated by MTT assay. Among them, the compound 3j exhibits significant inhibitory activity against MCF-7 human breast cancer cells with an IC50 value of 11.8 µM and low toxicity toward HaCaT human normal cells. The mechanism studies confirm that 3j can induce cell cycle arrest at G2/M phase in MCF-7 cells. Compared with compound 3e, 3j has stronger binding affinity to c-myc G-quadruplex (G4) DNA via π-π stacking and H-bonding interactions. Western blot analysis also further confirms that compound 3j can down-regulate the expression of c-myc in MCF-7 cells.
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Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Lactonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactonas/síntese química , Lactonas/química , Células MCF-7 , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
A 2,6-dibenzimidazole-appended naphthalene derivative flanking with two N-alkyl chains (sensor 4) was designed and applied for highly sensitive detection of picric acid (PA) in aqueous media. Driven by the hydrophobicity of alkyl chain and π-π stacking effect of aryl, sensor 4 can undergo self-assembly to form an orderly rod-like structure in H2O/THF (v/v, 90/10) solution, as shown by the dynamic light scattering (DLS) and scanning electron microscopy (SEM) studies. Sensor 4 shows high selectivity and sensitivity toward PA over other nitroaromatic explosives. DFT calculations and 1H NMR, the time-correlated single photon counting (TCSPC) experiments confirm that the quenching mechanism is due to both electron and energy transfer from the electron-rich sensor 4 to the electron-deficient PA. Sensor 4 can detect as low as 0.57 ppb PA in aqueous media and 11.46 ag cm-2 PA by contact mode. Importantly, sensor 4 exhibits low interference against common solvents, metal ions and anions. Thus, it is practically applicable for sensing PA in real environmental samples and vapor phase.
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Coating on the sperm surface, glycocalyx, plays a key role in sperm motility, maturation and fertilization. A comprehensive profile of sperm surface glycans will greatly facilitate both basic researches and clinical studies. Because of the capability of recognizing different glycan moieties, lectins are widely used in glycobiology. However, lacking high-throughput technology, limited lectins have been reported for analyzing the glycan of human sperm. In this study, we employed a lectin microarray for profiling the surface glycans of human sperm, on which 54 out of 91 lectins showed positive binding. Based on this technique, we compared lectin binding profiling of sperm with homozygous DEFB126 mutation (del/del) with that of wild type (wt/wt). DEFB126 was reported to contribute to the sialylation on sperm surface and its homozygous mutation was related to male subfertility. Six lectins (Jacalin/AIA, GHA, ACL, MPL, VVL and ABA) were found to develop lower binding affinity to sperm with del/del. Further validation showed that these lectins, especially ABA and MPL, can be potential biomarkers for clinical diagnosis of subfertility due to the mutation of DEFB126. Our research provides insight into the detection of some unexplained male subfertility, and the lectin microarray is generally applicable for infertility/subfertility sperm biomarker discovery.