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1.
J Nanosci Nanotechnol ; 20(2): 1013-1019, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383099

RESUMO

Nanomaterial-based flexible strain sensors have developed rapidly in recent years. Here, we propose a flexible strain sensor based on polydimethylsiloxane with carbon nanotubes (CNTs) and graphene quantum dots (GQDs). Different weight ratios of CNTs and GQDs were used as the sensitive units of the strain sensors. After analyzing the results of current-voltage curves and the strain effects of the sensors, we concluded that the introduction of GQDs played an important role in improving the sensitivity of the sensors. The gauge factor of the as-prepared strain sensors ranges from 0 to 841.42.

2.
Chemosphere ; 238: 124640, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524609

RESUMO

Triclosan (TCS) is a kind of chronic toxicity to aquatic organisms. Due to its highly effective antimicrobial, TCS has been widely applied in personal-care products, which naturally poses a potential risk to the ecological system and human health since its release into water-ecological environment. Therefore, it urgently demands a selective, easily separated, recyclable, and low-cost adsorbent to remove the residues of TCS from aquatic environments. In this study, a novel magnetic molecularly imprinted nano-polymers (TMIPs) were prepared for selective adsorption and convenient collection of TCS in aquatic samples, based on a core-shell technique using TCS as template molecule and SiO2-coated Fe3O4 nanoparticles as the support substrate. The functional groups, particle size, morphology and magnetic property of TMIPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy and vibrating sample magnetometer, respectively. The obtained TMIPs possessed excellent adsorption capacity (Qe = 53.12 mg g-1), speedy adsorption equilibrium time (2 min) and high selectivity (k' = 6.321) for TCS. Moreover, the pH-tolerance and stability tests manifested that the adsorption capacity of TMIPs for TCS was acid-resistance and could retain 94.2% of the maximum Qe after 5 times removal-regeneration cycles. The feature of magnetically susceptibility can simplify the procedures of sample handling in TCS determination, because the TMIPs of TCS are easy to be recycled from aquatic samples. As an application demonstration, the toxicity test in microalgae confirmed that a tiny amount of TMIPs could significantly eliminate the toxic effect of TCS on Chlamydomonas reinhardtii via the efficient binding with TCS.

3.
Food Chem ; 303: 125378, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31450176

RESUMO

This work introduces an inexpensive and user-friendly electrochemical platform for heavy metal determination in liquid food. Smart-phone connectivity, solid-state-microwave flow digestion and nano-Au-modified electrode are synchronously studied. A smart phone is adopted as the information terminal for universal purposes. A solid-state-microwave digestion device is developed to provide programmable digestion for liquid food in a digestion path. Microwave power curve and flow rate in digestion are studied and optimized. A nano-Au-modified electrode, as well as a homemade potentiostat and other electrodes, is used as a tool for electrochemical analyses. Behaviors of this method are evaluated with electrical measurement and stripping voltammetry. This method is used for sensing Cd2+, Pb2+ and Hg2+ in cow milk, orange juice and apple juice. It provides a sensitive response to ≥2 µg L-1 target ion, and shows satisfying stability and good accuracy in a task up to 72 h.


Assuntos
Técnicas Eletroquímicas/métodos , Sucos de Frutas e Vegetais/análise , Metais Pesados/análise , Leite/química , Smartphone , Animais , Cádmio/análise , Bovinos , Eletrodos , Feminino , Ouro/química , Chumbo/análise , Mercúrio/análise , Micro-Ondas
4.
J Pharm Biomed Anal ; 177: 112848, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31479998

RESUMO

Metabolic syndrome (MetS) is an important risk factor for type 2 diabetes, cardiovascular diseases and all-cause morbidity and mortality. Biomarkers can provide insight into the mechanism, facilitate early detection, and monitor progression of MetS and its response to therapeutic interventions. To identify potential biomarkers, we applied a non-targeted and targeted lipidomics method to characterize plasma metabolic profile in MetS patients. Metabolic profiling was performed on a non-target set (40 cases and 40 controls) on UHPLC-Q-TOF/MS and target set (80 MetS patients and 80 healthy controls) on UHPLC-Q-orbitrap MS. Using comprehensive screening and validation workflow, we identified a panel of three metabolites including PC(18:1/P-16:0), PC(o-22:3/22:3), PC(P-18:1/16:1). Our results indicated that the identified biomarkers may improve the risk prediction and provide a novel tool for monitoring of the progression of disease and response to treatment in MetS patients.

5.
Carbohydr Polym ; 227: 115332, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590887

RESUMO

Advanced oxidation processes (AOPs) based on activated persulfate have received extensive attention for sludge pretreatment. Persulfate (PS) is a persistent oxidant and the excess persulfate in the sludge affects the carbohydrate analysis using the traditional phenol-sulfuric acid method. In this study, an improved phenol-sulfuric acid method was developed for the determination of carbohydrates in the presence of persulfate, and a critical procedure was introduced before the conventional determination with the assistance of the chemical pretreatments. The best reagent was screened from four reductants (i.e. Na2S, KI, Na2SO3 and Na2S2O3) and two free-radical scavengers (i.e. phenol and benzoic), and the optimal conditions were determined based on the monosaccharides (i.e. glucose, galactose and mannose) and the polysaccharides in different EPS fractions from two activated sludges. The results showed that Na2SO3 was the best reagent for chemical pretreatment due to redox reaction, high selectivity and colorless oxidation product, and the others were not suitable as pretreatment reagents mainly since the reaction products affect the final spectral analysis. Besides, the optimal Na2SO3 concentration for eliminating the impact of PS was 150 mmol/L, and the relative deviation of measurement is less than 5% if the PS concentration was on more than 100 mmol/L, regardless of the kinds of carbohydrates. Compared with the anthrone-sulfuric acid method and the sulfuric method, the improved phenol-sulfuric acid method has a great advantage for determining the carbohydrate concentration in the presence of PS.

6.
Eur J Pharm Sci ; 141: 105134, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678425

RESUMO

Neuromuscular blockers (NMBs) selectively block neuromuscular transmission at the N2-nicotinic receptor on motor neurons to paralyze skeletal muscles, and are mainly used to facilitate tracheal intubation and surgical procedures. Rapid reversal is necessary in clinical practice to avoid profound block and reduce recovery time. Adamgammadex sodium is a modified γ-cyclodextrin derivative consisting of a lipophilic core and a hydrophilic outer end that forms an inactive tight inclusion complex with free molecules of rocuronium and vecuronium. In preclinical study, adamgammadex produced a concentration-dependent reversion effect of neuromuscular blockade induced by rocuronium in beagle dogs. Furthermore, adamgammadex had a less potential side effects than sugammadex and other clinical used neuromuscular block antagonists. In this study, the objective was to assess the safety, tolerability, and pharmacokinetics of single intravenous injection of adamgammadex in healthy volunteers. Approved by the China Food and Drug Administration, 52 healthy volunteers (half male and half female) were enrolled in this single-center, randomized, double-blind placebo-controlled study. No serious adverse effects were happened in this study. The overall frequency of adverse effects in adamgammadex was similar for that in placebo, and there was no specific adverse effect in adamgammadex. All of the volunteers bearing the adverse effects were recovered to normal without any treatment or intervention. In pharmacokinetic study, the value of half-time, Tmax, and clearance were not changed significantly, and the Cmax and AUC0-∞ increased with a similar ratio of the escalating doses. For dose proportionality analysis of adamgammadex, the estimate of slope was close to 1, and it was not significantly different from 1 after doses (AUC0-∞, 0.9965 [90%CI, 0.9468, 1.046]; Cmax, 0.9462 [90%CI, 0.8800, 1.012]). Therefore, adamgammadex exposure in plasma increased in a dose- proportional manner. The urinary route is a significant excretory pathway for adamgammadex, and it is mostly completed at 8 h. All the results in this study showed that adamgammadex may be a novel safe neuromuscular blockade reversal agent .

7.
Anal Chim Acta ; 1094: 106-112, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761035

RESUMO

Endogenous hydrogen sulfide (H2S) exists in multiple physiological processes. In order to further understand the action mechanism of H2S in cells and human body, we proposed a smart surface-enhanced Raman scattering (SERS) nanoprobe, Au core-4-mercaptobenzonitrile-Ag shell nanoparticle (Au@4-MBN@Ag), for the detection of endogenous H2S in living cells based on the reaction between Ag shell and sulfide species. 4-MBN was selected as the SERS reporter to avoid interference from cellular molecules. With the sulfide concentration increasing, the Ag2S constantly formed, and consequently the SERS signal intensity of Au@4-MBN@Ag gradually decreased owing to the weaker SERS activity of Ag2S. With the nanoprobes, this method not only offers a high sensitivity for H2S detection at an nM level, but also achieves the goal of non-background analysis. It displays satisfactory anti-interference capability and a good linear relationship with sulfide concentration ranging from 50 nM to 500 µM, and an estimated detection limit is 0.14 nM. The Au@4-MBN@Ag nanoprobes were successfully applied to detect endogenous H2S in living HepG2 cells stimulated by pyridoxal 5-phosphate monohydrate. This work offers a potential analytical method in the related research of H2S physiological function.

8.
Opt Express ; 27(22): 31913-31925, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684414

RESUMO

High power continuous-wave (CW) single-frequency 1342 nm lasers are of interest for fundamental research, particularly, for laser cooling of lithium atoms. Using the popular Nd:YVO4 laser crystal requires careful heat management, because strong thermal effects in the gain medium are the most severe limitations of output power. Here, we present a multi-segmented Nd:YVO4 crystal design that consists of three segments with successive doping concentrations, optimized using a theoretical model. In order to quantify the optimization, we measured the thermal lens power of conventional crystal designs and compare them to our multi-segmented design. The optimized design displays a two times lower thermal lens dioptric power for the same amount of absorbed pump power in the non-lasing case. Using the optimized design, we demonstrate a high power all-solid-state laser emitting 10.0 W single-frequency radiation at 1342 nm when operating the laser crystal at room temperature. Further integration of the laser allows us to operate the laser crystal below room temperature for improving output power up to 11.4 W at 8°C. This is explained by the reduction of energy-transfer upconversion and excited-state absorption effects. Stable free-running operation at the low temperature of 8 °C is achieved with the power stability of ± 0.42 % by peak-to-peak fluctuation and frequency peak-to-peak fluctuation of ± 72 MHz in three hours.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31685424

RESUMO

Two novel ruthenium(II) polypyridyl complexes, namely, [Ru(dmp)2(CAPIP)](ClO4)2 (Ru(II)-1) and [Ru(dmp)2(CFPIP)](ClO4)2 (Ru(II)-2), which respectively contain (E)-2-(2-(furan-2-yl)vinyl)-1H-imidazo[4,5-f][1,10]phen-anthroline (CAPIP) and (E)-2-(4-fluorostyryl)-1H-imidazo[4,5-f][1,10]phenanthroline. (CFPIP), were first designed and characterized (dmp = 2,9-dimethyl-1,10-phenanthroline). DNA binding experiments indicated that Ru(II) complexes interact with CT DNA through intercalative mode. In addition, the complexes Ru(II)-1 and Ru(II)-2, showed remarkable cell cytotoxicity, giving the respective IC50 values of 4.1 ±â€¯1.4 µM and 6.1 ±â€¯1.4 µM on the A549 cancer cells. These values indicated higher activity than CAPIP, CFPIP, cisplatin (8.2 ±â€¯1.4 µM) and other corresponding Ru(II) polypyridyl complexes. Furthermore, the Ru(II) complexes could arrive the cytoplasm through the cell membrane and accumulate in the mitochondria. Significantly, complexes Ru(II)-1 and Ru(II)-2 induced A549 cells apoptosis was mediated by increase of ROS levels and dysfunction of mitochondria, and resulted in cell cycle arrest and increased anti-migration activity on A549 cells. Overall, these results indicated that complexes Ru(II)-1 and Ru(II)-2 could be suitable candidates for further investigation as a chemotherapeutic agent in the treatment of tumors.

10.
BMC Genomics ; 20(1): 822, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699025

RESUMO

BACKGROUND: The enhancing incidence of carbapenem-resistant Klebsiella pneumoniae (CRKP)-mediated infections in Mengchao Hepatobiliary Hospital of Fujian Medical University in 2017 is the motivation behind this investigation to study gene phenotypes and resistance-associated genes of emergence regarding the CRKP strains. In current study, seven inpatients are enrolled in the hospital with complete treatments. The carbapenem-resistant K. pneumoniae whole genome is sequenced using MiSeq short-read and Oxford Nanopore long-read sequencing technology. Prophages are identified to assess genetic diversity within CRKP genomes. RESULTS: The investigation encompassed eight CRKP strains that collected from the patients enrolled as well as the environment, which illustrate that blaKPC-2 is responsible for phenotypic resistance in six CRKP strains that K. pneumoniae sequence type (ST11) is informed. The plasmid with IncR, ColRNAI and pMLST type with IncF[F33:A-:B-] co-exist in all ST11 with KPC-2-producing CRKP strains. Along with carbapenemases, all K. pneumoniae strains harbor two or three extended spectrum ß-lactamase (ESBL)-producing genes. fosA gene is detected amongst all the CRKP strains. The single nucleotide polymorphisms (SNP) markers are indicated and validated among all CRKP strains, providing valuable clues for distinguishing carbapenem-resistant strains from conventional K. pneumoniae. CONCLUSIONS: ST11 is the main CRKP type, and blaKPC-2 is the dominant carbapenemase gene harbored by clinical CRKP isolates from current investigations. The SNP markers detected would be helpful for characterizing CRKP strain from general K. pneumoniae. The data provides insights into effective strategy developments for controlling CRKP and nosocomial infection reductions.

11.
Front Immunol ; 10: 2527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708932

RESUMO

Background: Neuromyelitis optica spectrum disorder (NMOSD) is a neurological complication of primary Sjögren's syndrome (pSS). Objective: We aimed to explore potential serological differences between pSS patients with and without NMOSD. Methods: There were 4 pSS patients with NMOSD and 8 pSS patients without NMOSD enrolled as the screening group for two-dimensional difference gel electrophoresis (DIGE) analysis. Then differential expressed protein spots between groups were identified by MALDI-TOF/TOF MS. The levels of the identified potential biomarkers were verified by ELISA in a second independent cohort including 22 pSS patients with NMOSD, 26 pSS without NMOSD and 30 NMOSD patients. Results: Nine proteins were identified significantly differently expressed (more than 1.5-fold, p < 0.05) between these two groups. Serum levels of clusterin and complement factor H (CFH) were further verified by ELISA. Results showed that the serum clusterin was significantly higher in NMOSD with pSS than without (298.33 ± 184.52 vs. 173.49 ± 63.03 ng/ml, p < 0.01), while the levels of CFH were lower in pSS patients with NMOSD than without (24.19 ± 1.79 vs. 25.87 ± 3.98 ng/ml, p < 0.01). Conclusion: This is the first study of serological comparative proteomics between pSS patients with and without NMOSD. Serum clusterin and CFH might be potential biomarkers for pSS patients with NMOSD and play important role in the pathogenesis of the disease but needs further verification.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31693789

RESUMO

The stereodivergent Ir-catalyzed allylic alkylation and fluorination of acyclic ketones is described. α -Pyridyl- α -fluoroketones with vicinal tertiary and quaternary stereocenters were obtained in moderate to excellent yields and stereoselectivities. Distinct from the known stereodivergent synthesis where two different chiral catalysts are required in general, herein we report a sequence-dependent stereodivergent synthesis. With only one single chiral Ir catalyst, all four possible stereoisomers of the products are prepared from the same starting materials by simply adjusting the sequence of asymmetric allylic alkylation and fluorination, and variation of the absolute configration of the Ir catalyst.

13.
Asian J Androl ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31696835

RESUMO

Epididymitis can be caused by infectious and noninfectious etiological factors. While microbial infections are responsible for infectious epididymitis, the etiological factors contributing to noninfectious epididymitis remain to be defined. The present study demonstrated that damaged male germ cells (DMGCs) induce epididymitis in mice. Intraperitoneal injection of the alkylating agent busulfan damaged murine male germ cells. Epididymitis was observed in mice 4 weeks after the injection of busulfan and was characterized by massive macrophage infiltration. Epididymitis was coincident with an accumulation of DMGCs in the epididymis. In contrast, busulfan injection into mice lacking male germ cells did not induce epididymitis. DMGCs induced innate immune responses in epididymal epithelial cells (EECs), thereby upregulating the pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß), as well as the chemokines such as monocyte chemotactic protein-1 (MCP-1), monocyte chemotactic protein-5 (MCP-5), and chemokine ligand-10 (CXCL10). These results suggest that male germ cell damage may induce noninfectious epididymitis through the induction of innate immune responses in EECs. These findings provide novel insights into the mechanisms underlying noninfectious epididymitis, which might aid in the diagnosis and treatment of the disease.

14.
Int J Mol Sci ; 20(21)2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31690044

RESUMO

Gene therapy is manipulation in/of gene expression in specific cells/tissue to treat diseases. This manipulation is carried out by introducing exogenous nucleic acids, such as DNA or RNA, into the cell. Because of their negative charge and considerable larger size, the delivery of these molecules, in general, should be mediated by gene vectors. Non-viral vectors, as promising delivery systems, have received considerable attention due to their low cytotoxicity and non-immunogenicity. As research continued, more and more functional non-viral vectors have emerged. They not only have the ability to deliver a gene into the cells but also have other functions, such as the performance of fluorescence imaging, which aids in monitoring their progress, targeted delivery, and biodegradation. Recently, many reviews related to non-viral vectors, such as polymers and cationic lipids, have been reported. However, there are few reviews regarding functional non-viral vectors. This review summarizes the common functional non-viral vectors developed in the last ten years and their potential applications in the future. The transfection efficiency and the transport mechanism of these materials were also discussed in detail. We hope that this review can help researchers design more new high-efficiency and low-toxicity multifunctional non-viral vectors, and further accelerate the progress of gene therapy.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31691373

RESUMO

The treatment options for acute stroke combined with pulmonary infection are limited. Clinically, there are several therapies to promote blood circulation and dissipate blood stasis; these treatment options include ginkgolide B (GB), which has PAF (platelet activating factor) inhibiting effects. PAF-receptor (PAF-R) antagonists are used to treat a variety of inflammatory diseases, however, the potential of PAF-R antagonists as a treatment for lung infections remains unclear. The aim of the present study is to investigate the protective effect of GB on lipopolysaccharide (LPS)-induced inflammatory responses in A549 human pulmonary alveolar epithelial cells (HPAEpiC) in vitro. Cell viability and apoptosis were measured by CCK-8 and flow cytometry. TRIM37, Caspase-3, and NF-κBp65 expression levels were measured by real-time PCR and western blotting. The release of TNF-α and IL-1ß was measured by ELISA. The data indicates that GB may reduce TRIM37 expression by antagonizing the PAF-R pathway, thereby inhibiting the activation of nuclear factor-κB (NF-κB) and alleviating the inflammatory response of alveolar epithelial cells. This study is the first to provide insight into the therapeutic potential of GB and suggests that clinical application of GB in acute stroke combined with pulmonary inflammation may be efficacious. This article is protected by copyright. All rights reserved.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31754888

RESUMO

PURPOSE: The purpose of this study was to investigate changes in morphological and elastic properties, as estimated by B-mode ultrasound (B-US) and shear wave elastography (SWE), in volleyball athletes with patellar tendinopathy (PT) and changes after extracorporeal shockwave therapy (ESWT) as well as their relationships with US measurements and Victorian Institute of Sport Assessment-Patella (VISA-P) scores in PT. METHODS: Twelve healthy athletes (24 patellar tendons) and 31 volleyball athletes with PT (48 tendons) were included. All were examined by US and received VISA-P scores before the start of the study. The athletes received 3 months of ESWT and underwent US and VISA-P at 1 month and 3 months. VISA-P scores were used to evaluate therapeutic efficacy. Tendon thickness and cross-sectional area (CSA) were detected by B-US, and the elastic modulus was measured by SWE. Correlations between VISA-P and US measurements were calculated. RESULTS: Thickness, CSA, and elastic modulus of the patellar tendon in PT were higher than those in healthy athletes (P < 0.000). In PT with ESWT, VISA-P scores decreased by 22.1% (P < 0.000) and thickness decreased by 11.2% relative to baseline (P < 0.000). CSA decreased by 1.4% (P < 0.000). The elastic modulus decreased by 15.2% (P < 0.000). Elastic modulus, thickness, and CSA had significant negative correlations with VISA-P scores (P ≤ 0.005), with a stronger correlation between elastic modulus and VISA-P. CONCLUSION: Athletes with PT had stiffer and larger tendons than healthy athletes. SWE combined with B-US could clearly show the changes in tendon thickness, CSA, stiffness in PT, and changes after treatment. SWE combined with B-US provided visualization with quantitative, reproducible, and noninvasive imaging in the follow-up evaluation of PT and is worth promoting clinically.

17.
EBioMedicine ; 49: 232-246, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31680002

RESUMO

BACKGROUND: Hepatitis B surface antigen (HBsAg) is one of the important clinical indexes for hepatitis B virus (HBV) infection diagnosis and sustained seroconversion of HBsAg is an indicator for functional cure. However, the level of HBsAg could not be reduced by interferons and nucleoside analogs effectively. Therefore, identification of a new drug targeting HBsAg is urgently needed. METHODS: In this study, 6-AN was screened out from 1500 compounds due to its low cytotoxicity and high antiviral activity. The effect of 6-AN on HBV was examined in HepAD38, HepG2-NTCP and PHHs cells. In addition, the antivirus effect of 6-AN was also identified in mouse model. FINDINGS: 6-AN treatment resulted in a significant decrease of HBsAg and other viral markers both in vitro and in vivo. Furthermore, we found that 6-AN inhibited the activities of HBV SpI, SpII and core promoter by decreasing transcription factor PPARα, subsequently reduced HBV RNAs transcription and HBsAg production. INTERPRETATION: We have identified a novel small molecule to inhibit HBV core DNA, HBV RNAs, HBsAg production, as well as cccDNA to a minor degree both in vitro and in vivo. This study may shed light on the development of a novel class of anti-HBV agent.

18.
Inorg Chem ; 58(22): 15637-15643, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31702143

RESUMO

A double-walled MOF [Zn5(µ3-OH)2(DBTA)2(H2O)4]·solvents [1, H4DBTA = 2,2'-dihydroxy-1,1'-binaphthyl-3,3',6,6'-tetrakis(4-benzoic acid)] has been designed and constructed based on a rare Zn5 cluster. The resultant sample has enrichment of porous structure with high BET and Langmuir surface area. By virtue of multiaperture structure and plentiful catalytic sites of Brønsted (-OH) and Lewis acidic (ZnII), MOF 1 is a unique catalyst to synthesize cyclic carbonates from CO2 and epoxides with preferable repeatability.

19.
Colloids Surf B Biointerfaces ; 185: 110607, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31707230

RESUMO

Development of multifunctional compounds as both fluorescence probes and non-viral vectors is still difficult till date. It is necessary to overcome many hurdles such as the balance of hydrophilic and hydrophobic moieties, binding affinity between multifunctional compound and targeting substrate, the cytotoxicity of multifunctional compound, and so on. In this work, the performances of compound 1 on Cu2+ recognition, lysosome staining and siRNA (small interfering RNA) delivery were investigated. It was found that compound 1 exhibited high selectivity and sensitivity toward Cu2+ in aqueous solutions. The fluorescence emission of 1 was quenched by a factor of 42-fold in the presence of Cu2+ ions. Even in the common pure organic solutions, still more than 8-fold fluorescence quenching was achieved. Due to its high sensitivity to the pH, the complex of 1-Cu was also successfully applied in selective staining of lysosome in HeLa cells. Furthermore, cellular uptake experiment revealed that compound 1 showed good RNA delivery ability in HeLa, HepG2, U2Os and MC3T3-E1 cells, and its performance was better than commercial agents lipofectamine 2000 and 25 kDa PEI (Polyethylenimine). The RNA interference effect mediated by compound 1 was further evaluated by real-time fluorescent quantitative PCR experiment. Compound 1 showed much higher transfection efficacy than lipofectamine 2000 in MC3T3-E1 cells. Our study demonstrated that 1,8-naphthalimide- [12]aneN3 compound 1 with low cytotoxicity, high specificity towards Cu2+ and lysosome, high transfection efficacy, and low cost is an efficient multifunctional material both in molecular recognition and gene delivery.

20.
World J Microbiol Biotechnol ; 35(12): 180, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31728755

RESUMO

Derived from RNA, 5'-ribonucleotides, especially Inosine-5'-monophosphate (IMP) and guanosine-5'-monophosphate (GMP), can enhance the umami taste of soy sauce. In this study, the RNA content of three different salt-tolerant yeasts was examined. The most valuable strain was subjected to atmospheric and room-temperature plasma (ARTP) mutagenesis, which improved its RNA content by 160.54%. Regular fermentation with RNA-enhanced strain failed to increase the amount of 5'-ribonucleotides in the soy sauce due to hydrolysis by phosphatase. A two-stage fermentation strategy was then carried out. Aroma compounds were mainly synthesized in the first stage, and RNA-enriched biomass was massively produced in the second stage followed by heat treatment to inactivate phosphatase. After the proposed strategy was applied, IMP and GMP in the soy sauce reached 68.54 and 89.37 mg/L, respectively. Moreover, the amounts of key aroma compounds and organic acids significantly increased. Results may provide new insights for improving the quality of soy sauce through microorganism breeding and fermentation control.

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