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1.
Sleep Med ; 114: 109-118, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38181582

RESUMO

BACKGROUND: The pathophysiology of coronasomnia remains unclear. This study aimed to investigate changes in white matter (WM) microstructure and inflammatory factors in patients with sleep disorders (SD) characterized by poor sleep quantity, quality, or timing following coronavirus disease 2019 (COVID-19) infection in the acute phase (within one month) and whether these changes could be recovered at 3-month follow-up. METHODS: 29 acute COVID-19 patients with SD (COVID_SD) and 27 acute COVID-19 patients without SD (COVID_NonSD) underwent diffusion tensor imaging (DTI), tested peripheral blood inflammatory cytokines level, and measured Pittsburgh Sleep Quality Index (PSQI), and matched 30 uninfected healthy controls. Analyzed WM abnormalities between groups in acute phase and explored its changes in COVID_SD at 3-month follow-up by using tract-based spatial statistics (TBSS). Correlations between DTI and clinical data were examined using Spearman partial correlation analysis. RESULTS: Both COVID_SD and COVID_NonSD exhibited widespread WM microstructure abnormalities. The COVID_SD group showed specific WM microstructure changes in right inferior fronto-occipital fasciculus (IFOF) (lower fractional anisotropy [FA]/axial diffusivity [AD] and higher radial diffusivity [RD]) and left corticospinal tract (CST) (higher FA and lower RD) and higher interleukin-1ß (IL-1ß) compared with COVID_NonSD group. These WM abnormalities and IL-1ß levels were correlated PSQI score. After 3 months, the IFOF integrity and IL-1ß levels tended to return to normal accompanied by symptom improvement in the COVID_SD relative to baseline. CONCLUSION: Abnormalities in right IFOF and left CST and elevated IL-1ß levels were important neurophenotypes correlated with COVID_SD, which might provide new insights into the pathogenesis of neuroinflammation in SD patients induced by COVID-19.


Assuntos
COVID-19 , Distúrbios do Início e da Manutenção do Sono , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Imagem de Tensor de Difusão/métodos , Fibras Nervosas , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
2.
Mol Med Rep ; 28(6)2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37859613

RESUMO

Sepsis is a manifestation of the immune and inflammatory response to infection, which may lead to multi­organ failure. Health care advances have improved outcomes in critical illness, but it still remains the leading cause of death. Septic cardiomyopathy is heart dysfunction brought on by sepsis. Septic cardiomyopathy is a common consequence of sepsis and has a mortality rate of up to 70%. There is a lack of understanding of septic cardiomyopathy pathogenesis; knowledge of its pathogenesis and the identification of potential therapeutic targets may reduce the mortality rate of patients with sepsis and lead to clinical improvements. The present review aimed to summarize advances in the pathogenesis of cardiac dysfunction in sepsis, with a focus on mitochondrial dysfunction, metabolic changes and cell death modalities and pathways. The present review summarized diagnostic criteria and outlook for sepsis treatment, with the goal of identifying appropriate treatment methods for this disease.


Assuntos
Cardiomiopatias , Cardiopatias , Sepse , Humanos , Sepse/metabolismo , Cardiomiopatias/metabolismo , Insuficiência de Múltiplos Órgãos/complicações
3.
Molecules ; 28(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570615

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, and its incidence continues to increase each year. Yet, there is still no definitive drug that can stop its development. This review focuses mainly on lipotoxicity, oxidative stress, inflammation, and intestinal flora dysbiosis to understand NAFLD's pathogenesis. In this review, we used NCBI's PubMed database for retrieval, integrating in vivo and in vitro experiments to reveal the therapeutic effects of natural compounds on NAFLD. We also reviewed the mechanisms by which the results of these experiments suggest that these compounds can protect the liver from damage by modulating inflammation, reducing oxidative stress, decreasing insulin resistance and lipid accumulation in the liver, and interacting with the intestinal microflora. The natural compounds discussed in these papers target a variety of pathways, such as the AMPK pathway and the TGF-ß pathway, and have significant therapeutic effects. This review aims to provide new possible therapeutic lead compounds and references for the development of novel medications and the clinical treatment of NAFLD. It offers fresh perspectives on the development of natural compounds in preventing and treating NAFLD.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado , Inflamação/metabolismo , Estresse Oxidativo
4.
ChemSusChem ; 16(21): e202300865, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37491687

RESUMO

High-quality graphene obtained by chemical vapor deposition (CVD) technique holds significant importance in constructing innovative electronic and optoelectronic devices. Direct growth of graphene over target substrates readily eliminates cumbersome transfer processes, offering compatibility with practical application scenarios. Recent years have witnessed growing strategic endeavors in the preparation of transfer-free graphene with favorable quality. Nevertheless, timely review articles on this topic are still scarce. In this contribution, a systematic summary of recent advances in transfer-free synthesis of high-quality graphene on insulating substrates, with a focus on discussing synthetic strategies designed by elevating reaction temperature, confining gas flow, introducing growth promotor and regulating substrate surface is presented.

5.
Theranostics ; 13(10): 3245-3275, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37351163

RESUMO

Large bone defects are a major global health concern. Bone tissue engineering (BTE) is the most promising alternative to avoid the drawbacks of autograft and allograft bone. Nevertheless, how to precisely control stem cell osteogenic differentiation has been a long-standing puzzle. Compared with biochemical cues, physicomechanical stimuli have been widely studied for their biosafety and stability. The mechanical properties of various biomaterials (polymers, bioceramics, metal and alloys) become the main source of physicomechanical stimuli. By altering the stiffness, viscoelasticity, and topography of materials, mechanical stimuli with different strengths transmit into precise signals that mediate osteogenic differentiation. In addition, externally mechanical forces also play a critical role in promoting osteogenesis, such as compression stress, tensile stress, fluid shear stress and vibration, etc. When exposed to mechanical forces, mesenchymal stem cells (MSCs) differentiate into osteogenic lineages by sensing mechanical stimuli through mechanical sensors, including integrin and focal adhesions (FAs), cytoskeleton, primary cilium, ions channels, gap junction, and activating osteogenic-related mechanotransduction pathways, such as yes associated proteins (YAP)/TAZ, MAPK, Rho-GTPases, Wnt/ß-catenin, TGFß superfamily, Notch signaling. This review summarizes various biomaterials that transmit mechanical signals, physicomechanical stimuli that directly regulate MSCs differentiation, and the mechanical transduction mechanisms of MSCs. This review provides a deep and broad understanding of mechanical transduction mechanisms and discusses the challenges that remained in clinical translocation as well as the outlook for the future improvements.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Osteogênese/fisiologia , Mecanotransdução Celular , Materiais Biocompatíveis , Engenharia Tecidual , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular
6.
Food Res Int ; 165: 112393, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869464

RESUMO

The health-promoting activities of procyanidin extracts from hawthorn (HPCs) are closely related to their digestive behaviors, absorption, and colonic metabolism, all of which remain unknown for now and thus hinder further exploration. This study aims to explore the dynamic changes of HPCs during in vitro digestion and fermentation, as well as their Caco-2 permeability, focusing mainly on the interaction between gut microbiota and HPCs. The results showed that the digested HPC samples had characteristic absorption peaks at 280 nm, and there were absorption peaks in the stretching vibration zone, including OH and CC on the benzene ring, which suggested that procyanidins were the main components in HPCs after in vitro digestion. Meanwhile, HPCs had the highest stability in the oral phase. However, the total procyanidin content of HPCs decreased during gastrointestinal digestion, and flavan-3-ol dimers and trimers in HPCs are partially degraded into epicatechin. Uptake of epicatechin (4.07 %), procyanidin B2 (2.15 %), and procyanidin B5 (39.44 %) through Caco-2 monolayer was also observed in HPC treatment, while there was still a large portion of procyanidins that was not absorbed. Subsequent fermentation resulted in a decrease in pH along with the production of short-chain fatty acids (SCFAs), mainly due to the degradation and utilization of HPC, as indicated by a reduction of total procyanidins. Furthermore, the HPCs modulated gut microbial populations: down-regulated the abundances of Bacteroides, Fusobacterium, Enterococcus, Parabacteroides, and Bilophila, and up-regulated Escherichia-Shigella, Klebsiella, Turicibacter, Actinobacillus, Roseburia, and Blautia. Ultimately, epicatechin and procyanidin B2, B5 and C1 were converted into phenolic acids through the metabolism of Bacteroides, Sutterella, Butyrobacter and Blautia. 4-ethylbenzoic acid, 4-hydroxyphenylpropionic acid, 3,4-dihydroxyphenyl acetic acid were confirmed as the significant metabolites in the fermentation. These results elucidated the potential mechanisms of HPCs metabolism and their beneficial effects on gut microbiota and colonic phenolic acids production.


Assuntos
Adenocarcinoma , Catequina , Neoplasias Colorretais , Crataegus , Proantocianidinas , Humanos , Fermentação , Células CACO-2 , Digestão
7.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 34(10): 1107-1111, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36473574

RESUMO

Sepsis is a serious complication of infection, and its further development may lead to multi-organ dysfunction syndrome. Sepsis cardiomyopathy is a common complication of sepsis and has been directly linked to high mortality. Although the pathogenesis of septic cardiomyopathy is not fully understood, in-depth study of the pathogenesis of septic cardiomyopathy and the identification of its potential therapeutic targets may reduce mortality in patients with sepsis. Ferroptosis is an iron-dependent mode of cell death that has been shown to be involved in the pathophysiological mechanisms of many diseases. Some related studies have reported that ferroptosis may be a potential mechanism of septic cardiomyopathy. This review provides new insights into the mechanisms of mitochondrial dysfunction, lipid peroxidation, xc-system, glutathione peroxidase 4 (GPX4), iron metabolism and the role of ferroptosiswith septic cardiomyopathy for further research and treatment of septic cardiomyopathy.


Assuntos
Cardiomiopatias , Humanos
8.
Food Res Int ; 162(Pt A): 112022, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461244

RESUMO

This study aimed to explore the dynamic changes of structural properties of polysaccharide from Ziziphus Jujuba cv. Pozao (JPS) during in vitro digestion and fermentation as well as its impacts on gut microbiota. Gastrointestinal digestion resulted a significant decrease in the reducing sugar content (CR), while a slight increase in the molecular weight. However, no free monosaccharide was detected. During the gut microbial fermentation, the CR showed a trend of increasing at first and then decreasing, while the carbohydrate residue decreased with the releases of monosaccharides. Meanwhile, pH decreased along with the production of short-chain fatty acids due to the utilization of JPS. Furthermore, JPS regulated the composition of gut microbiota, such as promoting Megasphaera and unclassified_f_Veillonellaceae, while inhibiting Bacteroides, Lachnoclostridium, Parabacteroides, Sutterella, Lachnospiraceae UCG-010, and Butyicimonas; Sutterella, Megasphaera, and unclassified_f_Veillonellaceae might be the characteristic bacteria in JPS group compared to the Inulin Control group. It was also found that JPS significantly enriched the metabolic pathways of carbohydrate, energy and amino acid after fermentation. These results indicated that JPS was indigestible but played an essential role by regulating gut microbiota composition and metabolic functions, which provided a basis for the conclusion that JPS could protect intestinal barrier and enhance immunity in our previous study.


Assuntos
Microbioma Gastrointestinal , Ziziphus , Humanos , Fermentação , Polissacarídeos , Monossacarídeos , Digestão
9.
Int J Anal Chem ; 2022: 9195335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36199444

RESUMO

Buyang Huanwu Decoction (BHD) has lipid-lowering and antioxidant effects. In this study, HPLC was used to establish the fingerprint of extracts from different polar parts of BHD. Through the L02 cell lipid deposition model induced by oleic acid, extracts from different polar parts of BHD were administered for treatment. Oil red O staining, TG detection, and MDA detection were used to determine lipid deposition and antioxidant activity. The component-effect relationship is established by using grey relational analysis and PLSR analysis. The results showed that the extracts from different polar parts of BHD could reduce the levels of TG and MDA. The grey relational analysis showed that the peaks that contributed greatly to the reduction of TG and MDA were peaks 3, 16, 14, 10, 1, 15, 2, and 11, respectively. Peaks 1, 4, 9, 10, 14, 16, and 17 could reduce TG and MDA through PLSR analysis. According to the results of grey relational analysis and PLSR analysis, peaks 1, 10, 14, and 16 may have good lipid-lowering and antioxidant effects. This study provides a certain preliminary basis for follow-up research on lipid-lowering drugs.

10.
Molecules ; 27(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36234757

RESUMO

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and its prevalence is still growing rapidly. However, the efficient therapies for this kidney disease are still limited. The pathogenesis of DKD involves glucotoxicity, lipotoxicity, inflammation, oxidative stress, and renal fibrosis. Glucotoxicity and lipotoxicity can cause oxidative stress, which can lead to inflammation and aggravate renal fibrosis. In this review, we have focused on in vitro and in vivo experiments to investigate the mechanistic pathways by which natural compounds exert their effects against the progression of DKD. The accumulated and collected data revealed that some natural compounds could regulate inflammation, oxidative stress, renal fibrosis, and activate autophagy, thereby protecting the kidney. The main pathways targeted by these reviewed compounds include the Nrf2 signaling pathway, NF-κB signaling pathway, TGF-ß signaling pathway, NLRP3 inflammasome, autophagy, glycolipid metabolism and ER stress. This review presented an updated overview of the potential benefits of these natural compounds for the prevention and treatment of DKD progression, aimed to provide new potential therapeutic lead compounds and references for the innovative drug development and clinical treatment of DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Fibrose , Glicolipídeos/farmacologia , Humanos , Inflamassomos/metabolismo , Inflamação/metabolismo , Rim , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Crescimento Transformador beta/metabolismo
11.
Foods ; 11(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36140941

RESUMO

The interaction between polyphenols and polysaccharides plays an important role in increasing the turbidity stability of fruit juice and improving unpleasant sensory experiences. The binding adsorption behavior between hawthorn pectin (HP) and polyphenols (epicatechin and chlorogenic acid) accorded with the monolayer adsorption behavior driven by chemical action and were better fitted by pseudo-second order dynamic equation and Langmuir model. The HP binding sites (Qm) and adsorption capacity (Qe) to epicatechin were estimated at 75.188 and 293.627 µg/mg HP, respectively, which was about nine and twelve times higher than that of chlorogenic acid. The interaction between HP and polyphenols exhibited higher turbidity characteristics, particle size and lower zeta potential than epicatechin and chlorogenic acid alone. Meanwhile, according to Fourier Transform Infrared Spectroscopy (FT-IR) analysis, it could be speculated that the interaction between HP and polyphenols resulted in chemical combination. Moreover, ΔH < 0 and TΔS < 0, which indicated that the interaction between HP and polyphenols was mainly driven by hydrogen bonds and van der Waals forces.

12.
Chembiochem ; 23(16): e202200138, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35676202

RESUMO

Cations such as divalent magnesium ion (Mg2+ ) play an essential role in DNA self-assembly. However, the strong electrostatic shielding effect of Mg2+ would be disadvantageous in some situations that require relatively weak interactions to allow a highly reversible error-correcting mechanism in the process of assembly. Herein, by substituting the conventional divalent Mg2+ with monovalent sodium ion (Na+ ), we have achieved one-pot high-yield assembly of tile-based DNA polyhedra at micromolar concentration of tiles, at least 10 times higher than the DNA concentrations reported previously. This strategy takes advantage of coexisting counterions and is expected to surmount the major obstacle to potential applications of such DNA nanostructures: large-scale production.


Assuntos
Nanoestruturas , Nanotecnologia , Cátions , DNA , Magnésio , Conformação de Ácido Nucleico , Sódio
13.
Shanghai Kou Qiang Yi Xue ; 31(1): 48-53, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35587668

RESUMO

PURPOSE: To explore the effects of carbodiimide combined with different bonding techniques on the property of dentin bonding. METHODS: 64 third molars in vitro were randomly divided into 8 groups(n=8), including EWB and EWBa (no pretreatment+ethanol-wet bonding), E-EWB and E-EWBa (0.5 mol/L EDC+ethanol-wet bonding), E-WB and E-WBa (0.5 mol/L EDC+water-wet bonding), E-DB and E-Dba (0.5 mol/L EDC+dry bonding). Group EWB, E-EWB, E-WB and E-DB were immediate groups, while group EWBa, E-EWBa, E-WBa and E-DBa were aging groups. Six specimens in each group were randomly chosen to test shear bonding strength and then observe failure patterns. The remaining specimens were used to observe bonding interface under SEM. SPSS 20.0 software package was used for statistical analysis of the data. RESULTS: There was no significant difference in shear bonding strength between group EWB and E-EWB, group E-EWB and E-WB(P>0.05), while shear bounding strength in group E-EWB and E-WB were significantly greater than group E-DB(P<0.05). The shear bonding strength of group E-EWBa was significantly greater than group EWBa (P<0.05). The shear bonding strength of group E-EWBa, E-WBa and E-DBa was gradually decreased, and their differences were significant (P<0.05). The factors of EDC, bonding techniques and aging played a significant role in shear bonding strength (P<0.05). Interactions between EDC and aging was significant (P<0.05), and that between bonding techniques and aging was also significant (P<0.05). The main failure modes of the water-wet bonding and the ethanol-wet bonding were resin failure, adhesive interface failure and mixed failure. The main failure of dry bonding was adhesive interface failure. The thickest and densest hybrid layer were found in group E-EWB. Some tiny cracks were presented between the hybrid layer and adhesives layer in group EWBa and E-EWBa. Partially uneven cracks existed in the hybrid layer in group E-WBa, and that was more obvious in group E-DBa. CONCLUSIONS: EDC pretreatment combined with ethanol-wet adhesive technique acquires the optimal shear bonding strength and the durability of dentin bonding.


Assuntos
Colagem Dentária , Adesivos Dentinários , Condicionamento Ácido do Dente/métodos , Colagem Dentária/métodos , Cimentos Dentários , Dentina , Etanol , Teste de Materiais , Cimentos de Resina , Resistência à Tração , Água
14.
Viruses ; 14(3)2022 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-35336895

RESUMO

The existing zoonotic coronaviruses (CoVs) and viral genetic variants are important microbiological pathogens that cause severe disease in humans and animals. Currently, no effective broad-spectrum antiviral drugs against existing and emerging CoVs are available. The CoV main protease (Mpro) plays an essential role in viral replication, making it an ideal target for drug development. However, the structure of the Deltacoronavirus Mpro is still unavailable. Porcine deltacoronavirus (PDCoV) is a novel CoV that belongs to the genus Deltacoronavirus and causes atrophic enteritis, severe diarrhea, vomiting and dehydration in pigs. Here, we determined the structure of PDCoV Mpro complexed with a Michael acceptor inhibitor. Structural comparison showed that the backbone of PDCoV Mpro is similar to those of alpha-, beta- and gamma-CoV Mpros. The substrate-binding pocket of Mpro is well conserved in the subfamily Coronavirinae. In addition, we also observed that Mpros from the same genus adopted a similar conformation. Furthermore, the structure of PDCoV Mpro in complex with a Michael acceptor inhibitor revealed the mechanism of its inhibition of PDCoV Mpro. Our results provide a basis for the development of broad-spectrum antivirals against PDCoV and other CoVs.


Assuntos
Antivirais , Coronavirus , Animais , Antivirais/química , Antivirais/farmacologia , Coronavirus/genética , Deltacoronavirus , Peptídeo Hidrolases/química , Suínos
15.
Shanghai Kou Qiang Yi Xue ; 30(5): 488-492, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34888600

RESUMO

PURPOSE: To investigate the influence of carbodiimide (EDC) in water, ethanol and acetone on bonding performance of acetone-based etch-and-rinsing adhesive system. METHODS: Sixty-four third molars in vitro were randomly divided into 8 groups according to the types of pretreatment agents, with or without aging(n=8), group S0 and S0a: deionized water; group S and Sa: EDC in water; group E and Ea: EDC in ethanol; group B and Ba: EDC in acetone. After pretreatment, the adhesive specimens were prepared by Prime Bond NT. S0, S, E and B were immediate groups, and S0a, Sa, Ea and Ba groups were subjected to aging test for 5 000 times. Six specimens were randomly selected from each group to test the shear bond strength and observe the fracture mode. The remaining 2 specimens were used to observe the microstructure of bonding interface by scanning electron microscopy. The shear bond strength was statistically analyzed with SPSS 20.0 software package. RESULTS: It was found that the shear bond strength of group S was significantly higher than that of group S0, and the shear bond strength of group Sa was significantly higher than that of group S0a(P<0.05). There was no significant difference between groups S, E and B(P>0.05). The shear bond strength of Sa, Ea and Ba increased successively, and the difference was statistically significant(P<0.05). Three factor analysis of variance found that the main effect of EDC, aging and solvent alone was significantly different(P<0.05), and there was an interaction effect between EDC and aging(P<0.05). The fracture modes of immediate groups were mainly mixed failure, while the interface fracture was the most common in the aging groups. SEM observation showed that all the hybrid layers were uniform and complete in the immediate groups, and the largest crack in S0a group and a few cracks in Ba group. CONCLUSIONS: EDC pretreatment in water, ethanol, and acetone solvents can improve both the immediate and aging bonding strength of acetone-based etch-and-rinsing adhesive system. Acetone acts as the solvents of EDC maximizes the shear bond strength among the aging groups.


Assuntos
Colagem Dentária , Adesivos Dentinários , Acetona , Carbodi-Imidas , Resinas Compostas , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento , Solventes
16.
Protein Cell ; 11(2): 124-137, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31758528

RESUMO

Type VII secretion systems (T7SSs) are found in many disease related bacteria including Mycobacterium tuberculosis (Mtb). ESX-1 [early secreted antigen 6 kilodaltons (ESAT-6) system 1] is one of the five subtypes (ESX-1~5) of T7SSs in Mtb, where it delivers virulence factors into host macrophages during infection. However, little is known about the molecular details as to how this occurs. Here, we provide high-resolution crystal structures of the C-terminal ATPase3 domains of EccC subunits from four different Mtb T7SS subtypes. These structures adopt a classic RecA-like ɑ/ß fold with a conserved Mg-ATP binding site. The structure of EccCb1 in complex with the C-terminal peptide of EsxB identifies the location of substrate recognition site and shows how the specific signaling module "LxxxMxF" for Mtb ESX-1 binds to this site resulting in a translation of the bulge loop. A comparison of all the ATPase3 structures shows there are significant differences in the shape and composition of the signal recognition pockets across the family, suggesting that distinct signaling sequences of substrates are required to be specifically recognized by different T7SSs. A hexameric model of the EccC-ATPase3 is proposed and shows the recognition pocket is located near the central substrate translocation channel. The diameter of the channel is ~25-Å, with a size that would allow helix-bundle shaped substrate proteins to bind and pass through. Thus, our work provides new molecular insights into substrate recognition for Mtb T7SS subtypes and also a possible transportation mechanism for substrate and/or virulence factor secretion.


Assuntos
Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/metabolismo , Sistemas de Secreção Tipo VII/química , Sistemas de Secreção Tipo VII/metabolismo , Adenosina Trifosfatases/isolamento & purificação , Antígenos de Bactérias/química , Antígenos de Bactérias/isolamento & purificação , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Modelos Moleculares , Conformação Proteica , Especificidade por Substrato
17.
J Nanosci Nanotechnol ; 19(8): 4535-4542, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913745

RESUMO

The application of graphene oxide in water treatment is facing a rigorous challenge of how to separate nanoadsorbents from aqueous solution using conventional methods after adsorption. Herein, a new type of easily separated composite was fabricated using cellulose acetate (CA) crosslinked with graphene oxide (CAGO) and a simple vacuum freeze-drying method. The CAGO composites were subject to SEM, FTIR, TGA, and BET characterizations. The adsorption performance of the adsorbent for the removal of methylene blue (MB) was evaluated through investigating the experimental parameters such as initial dye concentration, temperature, adsorbent dose, contact time, and solution pH. The Langmuir and Freundlich isotherm models were applied to fit the equilibrium data. The maximum adsorption capacity of methylene blue onto the CAGO-4 composite was 374.53 mg/g at 323 K. The kinetic data showed a good determination with pseudo-second-order equation. Thermodynamic analysis indicated that the adsorption was an endothermic and spontaneous process.

18.
Eur J Med Chem ; 167: 472-484, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30784880

RESUMO

Since pyrithiobac (PTB) is a successful commercial herbicide with very low toxicity against mammals, it is worth exploring its derivatives for an extensive study. Herein, a total of 35 novel compounds were chemically synthesized and single crystal of 6-6 was obtained to confirm the molecular structure of this family of compounds. The novel PTB derivatives were fully evaluated against various biological platforms. From the bioassay results, the best AHAS inhibitor 6-22 displayed weaker herbicidal activity but stronger anti-Candida activity than PTB did. For plant pathogenic fungi, 6-26 showed excellent activity at 50 mg/L dosage. Preliminary insecticidal activity and antiviral activity were also observed for some title compounds. Strikingly, 6-5 exhibited a promising inhibitory activity against SARS-CoV Mpro with IC50 of 4.471 µM and a low cellular cytotoxicity against mammalian 293 T cells. Based on the results of molecular modeling, HOMO-1 was considered to be a factor that affects AHAS inhibition and a possible binding mode of 6-5 with SARS-CoV Mpro was predicted. This is the first time that PTB derivatives have been studied as biological agents other than herbicides. The present research hence has suggested that more attentions should be paid to compounds belonging to this family to develop novel agrochemicals or medicines.


Assuntos
Benzoatos/síntese química , Benzoatos/farmacologia , Fungos/efeitos dos fármacos , Herbicidas/síntese química , Acetolactato Sintase/antagonistas & inibidores , Antivirais/síntese química , Antivirais/farmacologia , Benzoatos/química , Desenho de Fármacos , Herbicidas/farmacologia , Herbicidas/uso terapêutico , Modelos Moleculares , Estrutura Molecular , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos
19.
Transl Oncol ; 10(6): 976-987, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29096246

RESUMO

Endometrial cancer (EC) is the most common familiar gynecologic malignant tumor identified in the female reproductive system and has been increasing yearly. In this study, we will identify the surface markers and stem cell markers related with cancer stem cells (CSCs) of EC. Tissue samples were obtained from endometrial cancer patients during surgical procedures. Single cells were isolated from the tissues for culturing, transfection into nude mice, and histopathology analysis. RT-PCR demonstrated that the cultured cells strongly expressed stemness-related genes, such as c-Myc, Sox-2, Nanog, Oct 4A, ABCG2, BMI-1, CK-18, Nestin and ß-actin. The expression of surface markers CD24, CD133, CD47, CD29, CD44, CXCR4, SSEA3 and SSEA4, CD24, and CD133 and chemokine markers such as CXCR4 were measured by flow cytometry. Then the double percentage of CD133+CXCR4+ cells constituted 7.2% and 9.3% in EC cells originated from two different patients, respectively. The CD133+CXCR4+ primary endometrial cancer cells grew faster, exhibited high expression of mRNA of stemness-related genes, produced more spheres, and had higher clonogenic ability than other subpopulations. They are also more resistant to anti-cancer drugs than other subpopulations. These findings indicate that CD133+CXCR4+ cells may possess some characteristics of CSCs in primary endometrial cancer. These cell surface markers may be useful for the development of drugs against CSC molecular targets or as a predictive marker for poor prognosis in primary endometrial cancer.

20.
Polymers (Basel) ; 10(1)2017 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30966065

RESUMO

Accurate determination of the relationships among packing mode, molecular structure and charge transfer mobility for oligothiophene analogues has been significantly impeded, due to the lack of crystal structure information. In the current study, molecular dynamics (MD) were used to investigate the packing mode of non-, methyl- and ethyl-substituted poly(3-alkylthiophenes) (P3ATs). Obvious conformational changes were observed when comparing the packed and isolated oligothiophene molecules, indicating the important influence of packing mode on the geometric structures of these materials. Considering the crucial role played by reorganization energy (RE) in the charge transfer process, both quantum mechanics (QM) and quantum mechanics/molecular mechanics (QM/MM) were performed to examine the impact of different conformations on energy. Our simulations revealed that the geometric structures have distinct effects on the RE. Our data suggest that MD could give a reliable packing mode of oligothiophene analogues, and that QM/MM is indispensable for precisely estimating RE.

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