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1.
Chemistry ; 30(22): e202304222, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38270386

RESUMO

ClC is the main family of natural chloride channel proteins that transport Cl- across the cell membrane with high selectivity. The chloride transport and selectivity are determined by the hourglass-shaped pore and the filter located in the central and narrow region of the pore. Artificial unimolecular channel that mimics both the shape and function of the ClC selective pore is attractive, because it could provide simple molecular model to probe the intriguing mechanism and structure-function relevance of ClC. Here we elaborated upon the concept of molecular hourglass plus anion-π interactions for this purpose. The concept was validated by experimental results of molecular hourglasses using shape-persistent 1,3-alternate tetraoxacalix[2]arene[2]triazine as the central macrocyclic skeleton to control the conductance and selectivity, and anion-π interactions as the driving force to facilitate the chloride dehydration and movement along the channel.

2.
Inorg Chem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950326

RESUMO

Inorganic materials doped with chromium (Cr) ions generate remarkable and adjustable broadband near-infrared (NIR) light, offering promising applications in the fields of imaging and night vision technology. However, achieving high efficiency and thermal stability in these broadband NIR phosphors poses a significant challenge for their practical application. Here, we employ crystal field engineering to modulate the NIR characteristics of Cr3+-doped Gd3Ga5O12 (GGG). The Gd3MgxGa5-2xGexO12 (GMGG):7.5% Cr3+ (x = 0, 0.05, 0.15, 0.20, and 0.40) phosphors with NIR emission are developed through the cosubstitution of Mg2+ and Ge4+ for Ga3+ sites. This cosubstitution strategy also effectively reduces the crystal field strength around Cr3+ ions, which results in a significant enhancement of the photoluminescence (PL) full width at half-maximum (fwhm) from 97 to 165 nm, alongside a red shift in the PL peak and an enhancement of the PL intensity up to 2.3 times. Notably, the thermal stability of the PL behaviors is also improved. The developed phosphors demonstrate significant potential in biological tissue penetration and night vision, as well as an exceptional scintillation performance for NIR scintillator imaging. This research paves a new perspective on the development of high-performance NIR technology in light-emitting diodes (LEDs) and X-ray imaging applications.

3.
Orthod Craniofac Res ; 27(4): 665-673, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38558502

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the therapeutic effect of modified clear Twin Block (CTB) aligner and traditional twin block (TB) appliance from skeletal, dentoalveolar and soft tissue changes in adolescents with skeletal class II malocclusion. METHODS: A total of 80 adolescents, included in this study from two medical centres, were distributed into CTB group, TB group and control group based on the treatment they received. Lateral cephalograms at pre-treatment (T1) and post-treatment (T2) were measured by modified Pancherz's cephalometric analysis, and dentoskeletal and soft tissue changes were analysed by independent-sample t-test, paired-sample t-test, ANOVA test and Scheffe's Post Hoc test. RESULTS: Seventy-five adolescents completed the study, including 32 in the CTB group, 32 in the TB group and 11 in the control group. Both CTB and TB treatment showed significant differences in most dentoskeletal and soft tissue measurements. Compared with the control group, improvements were observed in class II molar relationship through significant different in S Vert/Ms-S Vert/Mi in the CTB group (P < .01) and the TB group (P < .001), as well as deep overjet through significant different in S Vert/Is-S Vert/Ii in the CTB group (P < .001) and the TB group (P < .001). Besides, the CTB group also showed less protrusion of lower incisors and resulted in a more significant improvement in profile with fewer adverse effects on speaking, eating and social activities. CONCLUSIONS: For adolescents with skeletal class II malocclusion, CTB appliance was as effective as TB on improving dentoskeletal and soft tissue measurements, featuring more reliable teeth control and patient acceptance.


Assuntos
Cefalometria , Má Oclusão Classe II de Angle , Humanos , Má Oclusão Classe II de Angle/terapia , Má Oclusão Classe II de Angle/diagnóstico por imagem , Adolescente , Masculino , Feminino , Desenho de Aparelho Ortodôntico , Resultado do Tratamento , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Criança , Mandíbula/patologia , Maxila/patologia , Aparelhos Ortodônticos Removíveis
4.
Ecotoxicol Environ Saf ; 271: 115960, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219622

RESUMO

Triphenyl phosphate (TPhP) serves as a major organophosphorus flame retardant, and its induced neurodevelopmental toxicity has attracted widespread attention, but the mechanism remains unclear. In this study, we involved zebrafish to explore the new mechanism of TPhP inducing oxidative stress and ferroptosis to promote neurodevelopmental toxicity. The results suggested that TPhP affected the embryonic development, reduced the number of new neurons, and led to abnormal neural behavior in zebrafish larvae. TPhP also induced ROS accumulation, activated the antioxidant defense signal Nrf2 and Keap1, and significantly changed the activities of Acetylcholinesterase (AChE), Adenosine triphosphatase (ATPase) and glutathione S-transferase (GST). In addition, TPhP induced ferroptosis in zebrafish, which was reflected in the increase of Fe2+ content, the abnormal expression of GPX4 protein and genes related to iron metabolism (gpx4a, slc7a11, acsl4b, tfa, slc40a1, fth1b, tfr2, tfr1a, tfr1b and ncoa4). Astaxanthin intervention specifically inhibited ROS levels, and reversed SLC7A11 and GPX4 expression levels and Fe2+ metabolism thus alleviating ferroptosis induced by TPhP. Astaxanthin also partially reversed the activity of AChE, GST and the expression of neurodevelopmental-related genes (gap43, gfap, neurog1 and syn2a), so as to partially rescue the embryonic developmental abnormalities and motor behavior disorders induced by TPhP. More interestingly, the expression of mitochondrial apoptosis-related protein BAX, anti-apoptotic protein BCL-2, Caspase3 and Caspase9 was significantly altered in the TPhP exposed group, which could be also reversed by Astaxanthin intervention. In summary, our results suggested that TPhP exposure can induce oxidative stress and ferroptosis, thereby causing neurodevelopment toxicity to zebrafish, while Astaxanthin can partially reverse oxidative stress and reduce the neurodevelopmental toxicity of zebrafish larvae by activating Nrf2/Keap1/HO-1 signaling pathway.


Assuntos
Ferroptose , Retardadores de Chama , Organofosfatos , Feminino , Animais , Fator 2 Relacionado a NF-E2/genética , Peixe-Zebra , Acetilcolinesterase , Retardadores de Chama/toxicidade , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Espécies Reativas de Oxigênio , Compostos Organofosforados/toxicidade , Estresse Oxidativo , Xantofilas
5.
Inorg Chem ; 62(47): 19350-19357, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37960854

RESUMO

The visualized dual-modal stress-temperature sensing refers to the ability of a sensor to provide real-time and visible information about both stress and temperature and has indeed attracted significant interest in various fields. However, the development of convenient methods for achieving this capability remains a challenge. In this work, a dual-modal stress-temperature sensor is successfully fabricated using a ZnS/Cu@CsPbBr1.2I1.8 glass ceramics (GCs)/polydimethylsiloxane (PDMS) (ZCP) composite film. The tunable ML color is achieved by modulating the concentration of CsPbBr1.2I1.8 GCs in the ZCP composite films based on the light conversion process from ZnS/Cu to CsPbBr1.2I1.8 GCs. Additionally, the stress and temperature can be visualized simultaneously by integrating the ML intensity and ML color of the ZCP composite film. This feature allows for the real-time monitoring of automotive tire temperature by embedding the ZCP composite film on the tire surface, enabling a strong and stable response to both stress and temperature changes. Overall, this work offers a convenient, efficient, and repeatable approach for achieving visualized dual-modal stress-temperature sensing in the fields of mechanical engineering, structural health monitoring, and intelligent devices.

6.
Inorg Chem ; 62(40): 16485-16492, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37738045

RESUMO

The current optical anticounterfeit strategies that rely on multimode luminescence in response to the photon or thermal stimuli have significant importance in the field of anticounterfeiting and information encryption. However, the dependence on light and heat sources might limit their flexibility in practical applications. In this work, Er3+ single-doped CaF2 phosphors that show multistimuli-responsive luminescence have been successfully prepared. The as-obtained CaF2:Er3+ phosphor exhibits green photoluminescence (PL) and color-tunable up-conversation (UC) luminescence from red to green due to the cross-relaxation of Er3+ ions. Additionally, as-obtained CaF2:Er3+ phosphors also display green mechano-luminescence behavior, which is induced by the contact electrification between the CaF2 particles and PDMS polymers, enabling the phosphor to flexibly respond to mechanical stimuli. Moreover, feasible anticounterfeiting schemes with the capability of multistimuli-responsive and flexible decryption have been constructed, further expanding the application of optical materials in the field of advanced anticounterfeiting and information encryption.

7.
Angew Chem Int Ed Engl ; 62(23): e202302198, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37021747

RESUMO

Inspired by the unique structure and function of the natural chloride channel (ClC) selectivity filter, we present herein the design of a ClC-type single channel molecule. This channel displays high ion transport activity with half-maximal effective concentration, EC50 , of 0.10 µM, or 0.075 mol % (channel molecule to lipid ratio), as determined by fluorescent analysis using lucigenin-encapsulated vesicles. Planar bilayer lipid membrane conductance measurements indicated an excellent Cl- /K+ selectivity with a permeability ratio P Cl - ${{_{{\rm Cl}{^{- }}}}}$ /P K + ${{_{{\rm K}{^{+}}}}}$ up to 12.31, which is comparable with the chloride selectivity of natural ClC proteins. Moreover, high anion/anion selectivity (P Cl - ${{_{{\rm Cl}{^{- }}}}}$ /P Br - ${{_{{\rm Br}{^{- }}}}}$ =66.21) and pH-dependent conductance and ion selectivity of the channel molecule were revealed. The ClC-like transport behavior is contributed by the cooperation of hydrogen bonding and anion-π interactions in the central macrocyclic skeleton, and by the existence of pH-responsive terminal phenylalanine residues.

8.
Mol Pharm ; 19(4): 1033-1046, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35274963

RESUMO

Ionic liquids (ILs) are a class of nonmolecular compounds composed only of ions. Compared with traditional organic solvents, ILs have the advantages of wide chemical space, diverse and flexible structures, negligible vapor pressure, and high thermal stability, which make them widely used in many fields of modern science, such as chemical synthesis and catalytic decomposition, electrochemistry, biomass conversion, and biotransformation biotechnology. Because of their special characteristics, ILs have been favored in the pharmaceutical field recently, especially for the development of efficient drug delivery systems. So far, ILs have been successfully designed to promote the dissolution of poorly soluble drugs and the destruction of physiological barriers, such as the tight junction between the stratum corneum and the intestinal epithelium. In addition, ILs can also be combined with other drug strategies to stabilize the structure of small molecules. This Review mainly introduces the application of ILs in drug delivery, emphasizes the potential mechanism of ILs, and presents the key research directions of ILs in the future.


Assuntos
Líquidos Iônicos , Biotransformação , Sistemas de Liberação de Medicamentos , Líquidos Iônicos/química , Preparações Farmacêuticas/química , Solventes/química
9.
Environ Res ; 214(Pt 3): 114096, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35973458

RESUMO

Animal studies have indicated that exposure to polybrominated diphenyl ethers (PBDEs) during development can permanently affect blood/liver lipid balance. However, no epidemiological study has assessed the relationship between PBDEs in adipose tissues and blood lipid metabolism. In this study, we explored the associations between PBDEs levels in female adipose tissues and lipid profiles. We recruited 150 female patients undergoing plastic surgery from hospital in Shantou, China, collected their characteristics, clinical information, and adipose tissue samples. Fourteen PBDE congeners in adipose tissues were analyzed by gas chromatography-mass spectrometry (GC-MS). Multiple linear and logistic regression models were used to explore the relationships between PBDEs and lipid profiles, while restricted cubic spline (RCS) regression and Bayesian kernel machine regression (BKMR) models were used to evaluate the nonlinearity of mixtures. Median levels of ΣPBDEs and dominant congeners BDE-153, -209, and -183 in adipose tissues were 73.91, 26.12, 14.10 and 9.01 ng/g lipid, respectively. In the multiple linear model, BDE-153 and BDE-209 were negatively associated with triglycerides (TG), similarly for BDE-190 and total cholesterol (TC). While in the adjusted logistic models, BDE-138 was negatively associated with TC (OR = 0.76, 95%CI: 0.58, 0.99) and total lipids (TL) (OR = 0.76, 95%CI: 0.58, 0.99). Diastolic blood pressure was positively correlated with BDE-28 and BDE-71 (P < 0.05). Furthermore, a non-linear relationship was observed in BDE-138 and blood lipid levels using a RCS model (Pnonlinearity<0.05). BKMR analysis indicated that with the cumulative levels across PBDEs increased, the health risks of hypertriglyceridemia gradually rebounded, and the health risks of hypercholesterolemia and high total lipid gradually rebounded and then declined, but without statistical significance. PBDEs pollution was still prevalent in Shantou city, and several PBDE congeners were significant risk factors for dyslipidemia and blood pressure alteration. There exist deleterious effects of PBDEs and blood lipids.


Assuntos
Monitoramento Ambiental , Éteres Difenil Halogenados , Tecido Adiposo/química , Teorema de Bayes , China , Monitoramento Ambiental/métodos , Feminino , Éteres Difenil Halogenados/análise , Humanos , Lipídeos
10.
Arch Toxicol ; 96(11): 2913-2926, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35962800

RESUMO

With the widespread use of copper oxide nanoparticles (CuO-NPs), their potential toxicity to the environment and biological health has attracted close attention. Heterophil extracellular traps (HETs) are an innate immune mechanism of chicken heterophils against adverse stimuli, but excessive HETs cause damage. Here, we explored the effect and mechanism of CuO-NPs on HETs formation in vitro and further evaluated the potential role of HETs in chicken liver and kidney injury. Heterophils were exposed to 5, 10, and 20 µg/mL of CuO-NPs for 2 h. The results showed that CuO-NPs induced typical HETs formation, which was dependent on NADPH oxidase, P38 and extracellular regulated protein kinases (ERK1/2) pathways, and glycolysis. In in vivo experiments, fluorescence microplate and morphological analysis showed that CuO-NPs elevated the level of HETs in chicken serum and caused liver and kidney damage. Meanwhile, CuO-NPs caused hepatic oxidative stress (MDA, SOD, CAT, and GSH-PX imbalance), and also induced an increase in mRNA expression of their inflammatory and apoptosis-related factors (IL-1ß, IL-6, TNF-α, COX-2, iNOS, NLRP3, and Caspase-1, 3, 11). However, these results were significantly altered by DNase I (HETs degradation reagent). In conclusion, the present study demonstrates for the first time that CuO-NPs induce the formation of HETs and that HETs exacerbate pathological damage in chicken liver and kidney by promoting oxidative stress and inflammation, providing insights into immunotoxicity and potential prevention and treatment targets caused by CuO-NPs overexposure.


Assuntos
Armadilhas Extracelulares , Nanopartículas Metálicas , Animais , Caspases , Galinhas , Cobre/toxicidade , Ciclo-Oxigenase 2 , Desoxirribonuclease I/farmacologia , Interleucina-6 , Fígado , Nanopartículas Metálicas/toxicidade , NADPH Oxidases/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Oxidativo , Óxidos , Proteínas Quinases , RNA Mensageiro , Superóxido Dismutase , Fator de Necrose Tumoral alfa
11.
Spinal Cord ; 60(12): 1041-1049, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35606413

RESUMO

STUDY DESIGN: Systematic review and meta-analysis of preclinical literature. OBJECTIVES: To assess the effects of biomaterial-based combination (BMC) strategies for the treatment of Spinal Cord Injury (SCI), the effects of individual biomaterials in the context of BMC strategies, and the factors influencing their efficacy. To assess the effects of different preclinical testing paradigms in BMC strategies. METHODS: We performed a systematic literature search of Embase, Web of Science and PubMed. All controlled preclinical studies describing an in vivo or in vitro model of SCI that tested a biomaterial in combination with at least one other regenerative strategy (cells, drugs, or both) were included. Two review authors conducted the study selection independently, extracted study characteristics independently and assessed study quality using a modified CAMARADES checklist. Effect size measures were combined using random-effects models and heterogeneity was explored using meta-regression with tau2, I2 and R2 statistics. We tested for small-study effects using funnel plot-based methods. RESULTS: 134 publications were included, testing over 100 different BMC strategies. Overall, treatment with BMC therapies improved locomotor recovery by 25.3% (95% CI, 20.3-30.3; n = 102) and in vivo axonal regeneration by 1.6 SD (95% CI 1.2-2 SD; n = 117) in comparison with injury only controls. CONCLUSION: BMC strategies improve locomotor outcomes after experimental SCI. Our comprehensive study highlights gaps in current knowledge and provides a foundation for the design of future experiments.


Assuntos
Traumatismos da Medula Espinal , Regeneração da Medula Espinal , Animais , Humanos , Traumatismos da Medula Espinal/terapia , Materiais Biocompatíveis/uso terapêutico , Modelos Animais de Doenças , Procedimentos Neurocirúrgicos
12.
Ecotoxicol Environ Saf ; 248: 114326, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36435001

RESUMO

BACKGROUND: Polybrominated diphenyl ethers (PBDEs), a group of brominated flame retardants (BFRs), were reported exist extensively in various ecological environmental. Studies have indicated that PBDEs induce reproductive toxic effects on human health, but the mechanisms remain poorly understood. In this study, the adult female zebrafish were used to investigate the effects of 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) on the reproductive endocrine system and its mechanism. METHODS: Female zebrafish (AB strains) were continuously exposed to BDE-47 at the concentrations of 0, 10, 50, 100 and 500 µg/L till 21 days. The morphology of ovary were stained and evaluated with hematoxylin-eosin (H&E), and levels of sex hormones including follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T) and 17ß-estradiol (E2) and the biomarkers of oxidative stress such as superoxide dismutase (SOD) and malondialdehyde (MDA), were measured via ELISA. Subsequently, the expression of genes along the hypothalamic pituitary-gonad (HPG) and oxidative stress were determined using quantitative real-time PCR (qRT-PCR). RESULT: The results showed that exposure to high level of BDE-47 reduced the index of condition factor (CF) and gonadosomatic index (GSI). Treatment with BDE-47 impaired the normal development and structure of oocytes in zebrafish ovary. Moreover, the steroid hormone of FSH, LH, T and E2 were significantly decreased in BDE-47 exposure group. A dose-dependent elevation in SOD activity and MDA levels were recorded. Meanwhile, the transcription level of cyp19a, cyp19b, fshß, lhß were up-regulated while the transcription of fshr, lhr, cyp17a, 17ßhsd were down-regulated in the gonad of female adult zebrafish. CONCLUSION: Exposure to BDE-47 have detrimental impact on the development of ovary, decreasing sex hormone levels, inducing oxidative damage as well as altering HPG axis-related genes.


Assuntos
Éter , Éteres Difenil Halogenados , Adulto , Humanos , Animais , Feminino , Éteres Difenil Halogenados/toxicidade , Peixe-Zebra , Etil-Éteres , Hormônio Luteinizante , Hormônio Foliculoestimulante , Superóxido Dismutase
13.
Ecotoxicol Environ Saf ; 248: 114310, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36423367

RESUMO

Polybrominated biphenyl ethers (PBDEs) are new persistent pollutants that are widely exist in the environment and have many toxic effects. However, their toxicity mechanisms on neurodevelopment are still unclear. In this study, zebrafish embryos were exposed to 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) (control, 10, 50 and 100 µg/L) at 2 h postfertilization (hpf) - 7 dpf. Locomotion analysis indicated that BDE-47 increased spontaneous coiling activity in zebrafish embryos under high-intensity light stimuli and decreased locomotor in zebrafish larvae. RNA-Seq analysis revealed that most of the up-regulated pathways were related to the metabolism of cells and tissues, while the down-regulated pathways were related to neurodevelopment. Consistent with the locomotion and KEGG results, BDE-47 affected the expression of genes for central nervous system (gfap, mbpa, bdnf & pomcb), early neurogenesis (neurog1 & elavl3), and axonal development (tuba1a, tuba1b, tuba1c, syn2a, gap43 & shha). Furthermore, BDE-47 interfered with gene expression of the Wnt signaling pathway, especially during embryonic stages, suggesting that the mechanisms of BDE-47 toxicity to zebrafish at various stages of neurodevelopment may be different. In summary, early neurodevelopment effects and metabolic disturbances may have contributed to the abnormal neurobehavioral changes induced by BDE-47 in zebrafish embryos/larvae, suggesting the neurodevelopmental toxicity of BDE-47.


Assuntos
Éter , Peixe-Zebra , Animais , Peixe-Zebra/genética , Transcriptoma , Éteres Difenil Halogenados/toxicidade , Etil-Éteres , Larva
14.
J Environ Manage ; 318: 115503, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35752004

RESUMO

Spent carbon cathode (SCC) as a hazardous solid waste produced in aluminum electrolysis industry, contains plenty valuable components but generate a seriously threat to the environment. This paper focus on a closed-circuit cycle process for direct treatment of SCC based on the hydrothermal acid-leaching method. Thermodynamic calculation, single factor experiment, orthogonal experiment and kinetic study are utilized to obtain the leaching properties of impurities, optimize the leaching conditions, study the influence of conditions on leaching, and capture the restriction factors of leaching. The results indicate that the carbon content of the treated SCC can reach 97.3% when the leaching condition attach the optimal (liquid-solid ratio of 25 mL/g, temperature of 413 K, time of 270 min and acid concentration of 4 mol/L), and liquid-solid ratio is regarded as the crucial factor influencing on that. In addition, the activation energy of impurities reaches 6.25 kJ/mol and the whole leaching process is controlled by the diffusion extent. Finally, the filtrate after the hydrothermal acid leaching is treated, and calcium fluoride, cryolite and sodium chloride are successfully separated. The proposed process eliminates the harm of SCC to the environment, and completes a closed-circuit cycle for the treatment of SCC and recovery of valuable components. It enriches the hydrometallurgical processes of SCC, and provides an attractive scheme for the treatment of SCC.


Assuntos
Fontes de Energia Elétrica , Lítio , Carbono , Eletrodos , Resíduos Perigosos , Reciclagem/métodos
15.
Molecules ; 27(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35807403

RESUMO

Determining the level of phthalic acid esters (PAEs) in packaged carbonated beverages is a current need to ensure food safety. High-selectivity and -accuracy identification of individual PAEs can be achieved by chromatographic and mass spectrometric (MS) techniques. However, these methods are slow; involve complicated, expensive instruments in professional laboratories; and consume a large amount of organic solvents. As such, a food analysis method is needed to conveniently and rapidly evaluate multiple contaminants on site. In this study, with the assistance of ultrasound, we quickly determined the total PAEs in soft drinks using 1.5 mL of petroleum ether in one step. Then, we determined the characteristic molecular fluorescence spectrum of all PAEs in samples (excitation (Ex)/emission (Em) at 218/351 nm) using selectively concentrated sulfuric acid derivatization. The relative standard deviations of the fluorescent intensities of mixed solutions with five different PAEs were lower than 7.1% at three concentration levels. The limit of detection of the proposed method is 0.10 µmol L-1, which matches that of some of the chromatographic methods, but the proposed method uses less organic solvent and cheaper instruments. These microextraction devices and the fluorescence spectrometer are portable and provide an instant result, which shows promise for the evaluation of the total level of PAEs in beverages on site. The proposed method successfully detected the total level of PAEs in 38 kinds of soft drink samples from local supermarkets, indicating its potential for applications in the packaged beverage industry.


Assuntos
Petróleo , Ácidos Ftálicos , Alcanos , Bebidas Gaseificadas/análise , Ésteres/análise , Limite de Detecção , Petróleo/análise , Ácidos Ftálicos/química , Solventes/análise
16.
Xenotransplantation ; 28(2): e12663, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33230864

RESUMO

BACKGROUND: Genetically modified pigs (GMP) have been developed to alleviate the shortage of donors in human islet transplantation and rejection. In this study, we characterized and compared the islets from GalTKO, GalTKO/hCD46, GalTKO/hCD46/hCD39, and wild-type (WT) neonatal pigs. METHODS: Islets were isolated from GMP and WT pig pancreases that have been packaged with ice pack for at least 24 hours. The difference in gene expression and function of islets were evaluated by microarray analysis and transplantation of islets under the kidney capsule of streptozotocin-induced diabetic immune-deficient mice, respectively. Blood glucose levels of these mice were monitored weekly post-transplantation for >100 days, and islet grafts were collected and evaluated for the presence of endocrine cells. RESULTS: The genes involved in extracellular components, cell adhesion, glucose metabolism, and inflammatory response are differentially expressed between GMP and WT pig islets. Variation in the ability of pig islets in correcting the diabetic state of the mouse recipients appears to be dependent on the pig donor. In addition, prolonged cold ischemia time had a negative effect on the transplant outcome. All normoglycemic mice were able to respond well to glucose challenge despite the initial differences in the ability of islet transplants to reverse their diabetic state. Islet xenografts of normoglycemic mice contained abundant insulin- and glucagon-positive cells. CONCLUSION: The effect of GMP and WT neonatal pig islet transplants on hyperglycemia in mice appears to be dependent on the pig donor, and prolonged cold ischemia time negatively affects the neonatal pig islet transplant outcome.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Isquemia Fria , Camundongos , Pâncreas , Transplante Heterólogo
17.
Bioorg Chem ; 117: 105453, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34736138

RESUMO

Human epidermal growth factor receptor 2 (HER2) has been recognized as an important therapeutic target for its overexpression in many cancers. Trastuzumab is a monoclonal antibody targeting HER2, which has been approved by FDA to treat HER2-positive cancer. In this research, cyclic peptide Cyclo-GCGPep1 was designed based on the binding mode between antibody and HER2 protein in silico, which has been confirmed possessing good affinity with HER2. Cyclo-GCGPep1 was also used to construct peptide-drug conjugates with Camptothecin. Biological evaluations demonstrated that Conjugate 1 has a good antiproliferative activity on SK-BR-3 and NCI-N87 cells. Conjugate 1 retained the pro-apoptotic and Topo I inhibitory ability of Camptothecin. Meanwhile, it has good targeting ability towards HER2-positive cells with the help of Cyclo-GCGPep1. It also has better permeability in the tumor spheroid model than Camptothecin. In summary, the design of cyclic peptide derived from antibody is of significance for the discovery of targeting peptides and Conjugate 1 is expected as a good therapeutic agent for HER2-positive cancers.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Peptídeos Cíclicos/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Receptor ErbB-2/metabolismo , Relação Estrutura-Atividade , Trastuzumab/química
18.
Bioorg Chem ; 111: 104849, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33798846

RESUMO

Accumulating researches have contributed much effect to discover novel chemotherapeutic drug for leukemia with expeditious curative effect, of which bromodomain-containing protein 4 (BRD4) inhibitor is considered as a eutherapeutic drug which has presented efficient cell proliferation suppression effect. In this study, we disclosed a series of phenylisoxazole sulfonamide derivatives as potent BRD4 inhibitors. Especially, compound 58 exhibited robust inhibitory potency toward BRD4-BD1 and BRD4-BD2 with IC50 values of 70 and 140 nM, respectively. In addition, compound 58 significantly suppressed cell proliferation of leukemia cell lines HL-60 and MV4-11 with IC50 values of 1.21 and 0.15 µM. In-depth study of the biological mechanism of compound 58 exerted its tumor suppression effect via down-regulating the level of oncogene c-myc. Moreover, in vivo pharmacokinetics (PK) study was conducted and the results demonstrated better pharmacokinetics features versus (+)-JQ1. In summary, our study discovers that compound 58 represents as a novel BRD4 inhibitor for further investigation in development of leukemia inhibitor with potentiality.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Desenho de Fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Sulfonamidas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas
19.
Bioorg Chem ; 106: 104492, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268008

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor agonists as an effective approach for type 2 diabetes mellitus (T2DM) has been explored extensively, multi agonists based on GLP-1 may have better clinical benefits on obesity, Nonalcoholic steatohepatitis (NASH) and other metabolic diseases. To get multi agonists based on GLP-1, 15 conjugates were designed, synthesized, and tested for biological activity. GLP-1/glucagon dual receptor agonist E1 showed moderate long-acting hypoglycemic effect, CY-5 and CY-16 with GLP-1/GIP dual receptor agonistic activity exhibited longer duration of continuous blood glucose stabilization. The long-acting hypoglycemic effect was equal to that of semaglutide. Although they have lost the agonistic activity on glucagon receptor, chronic in vivo studies on T2DM mice and diet-induced obesity (DIO) mice showed that CY-5 can effectively reduce food intake, inhibit body weight gain, repair islets damage and improve the glucose tolerance. One month treatment on NASH mice showed that CY-5 can significantly lower the TG, TC, AST, ALT and LDL-C and increase the HDL-C. CY-5 can also improve the liver vacuolation, reduce fat accumulation and delay the process of the fibrosis. The liver protection effect is better than that of semaglutide. In summary, CY-5 is a promising candidate for the treatment of metabolic diseases and worthy for further development.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Obesidade/tratamento farmacológico , Peptídeos/farmacologia , Receptores dos Hormônios Gastrointestinais/agonistas , Animais , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Descoberta de Drogas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Hipoglicemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Estrutura Molecular , Obesidade/induzido quimicamente , Obesidade/metabolismo , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Receptores dos Hormônios Gastrointestinais/metabolismo , Estreptozocina , Relação Estrutura-Atividade
20.
Ecotoxicol Environ Saf ; 212: 111991, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548570

RESUMO

Bisphenol A (BPA), an endocrine-disrupting chemical, is present in everyday-used consumables and common household products. Although the side effects of BPA have been sufficiently explored, little is known the effects of environmentally relevant low levels of BPA on chondrogenesis in skeletal development. Here we used a morphological approach to investigate whether exposure to BPA (0, 0.0038, 0.05, 0.1, 1.0 µM) could affect craniofacial cartilage development of zebrafish embryo. Furthermore, we sought to determine receptor-mediated BPA induced chondrogenesis toxicity by co-exposing developing embryos to BPA and various inhibitors. Low-dose BPA affected heart rate and induced body and head elongation of larvae. Quantitative morphometric and histopathological analysis revealed that BPA exposure changed the angle and length of craniofacial cartilage elements and disrupted chondrocytes. BPA induced pharyngeal cartilage defects via multiple cellular pathways, including estrogen receptor, androgen receptor, and estrogen-related receptors. Our findings demonstrate that BPA alters the normal development of cartilage and craniofacial structures in zebrafish embryos. Furthermore, in this study we find multiple cellular pathways mediating the effects of BPA-induced craniofacial chondrogenesis toxicity. Further experiments will allow for establishing a connection between BPA and increased risk of congenital malformation of the facial cranium in BPA-exposed populations.


Assuntos
Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Cartilagem , Condrogênese/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Larva/efeitos dos fármacos , Peixe-Zebra/metabolismo
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