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1.
Phys Chem Chem Phys ; 26(15): 11738-11745, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38563831

RESUMEN

High-performance sodium-ion batteries (SIBs) require anode materials with high capacity and fast kinetics. Based on first-principles calculations, we propose BC3N2 and BC3N2/graphene (B/G) heterostructure as potential SIB anode materials. The BC3N2 monolayer exhibits intrinsic metallic behavior. In addition, BC3N2 possesses a low Na+ diffusion barrier (0.15 eV), a high storage capacity (777 mA h g-1), a low open-circuit voltage (0.72 V), and a tiny axial expansion (0.36%). Compared with the BC3N2 monolayer, the B/G heterostructure exhibits a lower diffusion barrier of 0.027 eV, suggesting a much faster diffusion. More importantly, although the B/G heterostructure possesses heavier molar weight, its theoretical capacity (689 mA h g-1) is comparable to that of the BC3N2 monolayer. Based on the above-mentioned properties, we hope both the BC3N2 monolayer and the B/G heterostructure would be promising anodes for SIBs.

2.
Acta Pharmacol Sin ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684800

RESUMEN

Ulcerative colitis (UC) is associated with changed dietary habits and mainly linked with the gut microbiota dysbiosis, necroptosis of epithelial cells, and mucosal ulcerations. Liver dysfunction and abnormal level of liver metabolism indices were identified in UC patients, suggesting a close interaction between gut and liver disorders. Methionine-choline deficient diet (MCD) has been shown to induce persistent alterations of gut microbiota and metabolome during hepatitis. In this study we further explored the disease phenotypes in UC patients and investigated whether MCD functioned as a trigger for UC susceptibility. After assessing 88 serum specimens from UC patients, we found significant liver dysfunction and dyslipidemia including abnormal ALT, AST, TG, TC, LDL-c and HDL-c. Liver dysfunction and dyslipidemia were confirmed in DSS-induced colitis mice. We fed mice with MCD for 14 days to cause mild liver damage, and then treated with DSS for 7 days. We found that MCD intake significantly exacerbated the pathogenesis of mucosal inflammation in DSS-induced acute, progressive, and chronic colitis, referring to promotion of mucosal ulcers, colon shortening, diarrhea, inflammatory immune cell infiltration, cytokines release, and abnormal activation of inflammatory macrophages in colon and liver specimens. Intraperitoneal injection of clodronate liposomes to globally delete macrophages dramatically compromised the pathogenesis of MCD-triggering colitis. In addition, MCD intake markedly changed the production pattern of short-chain fatty acids (SCFAs) in murine stools, colons, and livers. We demonstrated that MCD-induced colitis pathogenesis largely depended on the gut microbes and the disease phenotypes could be transmissible through fecal microbiota transplantation (FMT). In conclusion, this study supports the concept that intake of MCD predisposes to experimental colitis and enhances its pathogenesis via modulating gut microbes and macrophages in mice.

3.
Mar Drugs ; 22(5)2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38786621

RESUMEN

Alginate oligosaccharides (AOS), products of alginate degradation by endotype alginate lyases, possess favorable biological activities and have broad applications. Although many have been reported, alginate lyases with homogeneous AOS products and secretory production by an engineered host are scarce. Herein, the alginate lyase AlyC7 from Vibrio sp. C42 was characterized as a trisaccharide-producing lyase exhibiting high activity and broad substrate specificity. With PelB as the signal peptide and 500 mM glycine as the additive, the extracellular production of AlyC7 in Escherichia coli reached 1122.8 U/mL after 27 h cultivation in Luria-Bertani medium. The yield of trisaccharides from sodium alginate degradation by the produced AlyC7 reached 758.6 mg/g, with a purity of 85.1%. The prepared AOS at 20 µg/mL increased the root length of lettuce, tomato, wheat, and maize by 27.5%, 25.7%, 9.7%, and 11.1%, respectively. This study establishes a robust foundation for the industrial and agricultural applications of AlyC7.


Asunto(s)
Escherichia coli , Polisacárido Liasas , Trisacáridos , Vibrio , Polisacárido Liasas/metabolismo , Trisacáridos/biosíntesis , Vibrio/enzimología , Especificidad por Sustrato , Alginatos , Zea mays , Oligosacáridos
4.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1137-1143, 2024 Mar.
Artículo en Zh | MEDLINE | ID: mdl-38621960

RESUMEN

The protection, development, and utilization of medicinal plant resources are important cornerstones of maintaining human health. However, due to factors such as the reduction of high-quality land resources, deterioration of ecological environments, and excessive and disorderly resource development, medicinal plant resources are becoming scarce, and some of them are insufficiently supplied. With the proposal of "the Belt and Road" Initiative, the cooperation between China and "the Belt and Road" partners(the countries and regions involved in "the Belt and Road" Initiative)is increasingly close, which provides a new opportunity for carrying out trade of medicinal plant resources and alleviating the problem of imbalance and relative inadequacy of medicinal plant resources in countries. This study first determined the distribution and species information of plant resources in countries and regions involved in "the Belt and Road" Initiative by investigating the database of plant distribution and that of medicinal plant resources. Then, according to the published data from the International Union for Conservation of Nature(IUCN) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora(CITES), this study identified the rare and endangered medicinal plants and the medicinal plants under trade control in countries and regions involved in "the Belt and Road" Initiative and finally sorted out the list of potential medicinal plant resources in countries and regions involved in "the Belt and Road" Initiative that can be used by China. This data resource can not only be used for the overall protection of important endangered species but also scientifically guide the development and utilization of medicinal resources, providing guidance and a theoretical basis for the sustainable development of medicinal plant resources in countries and regions involved in "the Belt and Road" Initiative.


Asunto(s)
Plantas Medicinales , Humanos , Animales , Comercio , Internacionalidad , Ambiente , China , Especies en Peligro de Extinción
5.
Phys Chem Chem Phys ; 25(42): 29224-29232, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37873573

RESUMEN

Lithium-ion batteries (LIBs) remain irreplaceable for clean energy storage applications. The intrinsic metallic nature of penta-SiCN ensures its promising application in the electrodes of LIBs. Using first-principles calculations, we evaluate the performance of the intrinsic metallic penta-SiCN monolayer as the anode material for LIBs. Penta-SiCN exhibits a low diffusion energy barrier (0.107 eV) for Li atom migration on Si18C18N18, while the diffusion energy barrier for vacancy migration on Li17Si18C18N18 is only 0.006 eV. Additionally, penta-SiCN possesses a high theoretical capacity of 1485.98 mA h g-1, average open-circuit voltage of 0.97 V, and small volume expansion of 1%. Remarkably, penta-SiCN exhibits robust wettability towards the electrolytes (solvent molecules and metal salts) widely used in commercial LIBs, indicating the excellent compatibility in electrode applications. These intriguing theoretical findings make penta-SiCN a high performance anode material for LIBs.

6.
Appl Environ Microbiol ; 88(23): e0155922, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36394323

RESUMEN

Alginate lyases play a vital role in the degradation of alginate, an important marine carbon source. Alginate is a complex macromolecular substrate, and the synergy of alginate lyases is important for the alginate utilization by microbes and the application of alginate lyases in biotechnology. Although many studies have focused on the synergy between different alginate lyases, the synergy between two alginate lyase domains of one alginate lyase has not been reported. Here, we report the synergism between the two catalytic domains of a novel alginate lyase, AlyC6', from the marine alginate-degrading bacterium Vibrio sp. NC2. AlyC6' contains two PL7 catalytic domains (CD1 and CD2) that have no sequence similarity. While both CD1 and CD2 are endo-lyases with the highest activity at 30°C, pH 8.0, and 1.0 M NaCl, they also displayed some different properties. CD1 was PM-specific, but CD2 was PG-specific. Compared with CD2, CD1 had higher catalytic efficiency, but lower substrate affinity. In addition, CD1 had a smaller minimal substrate than CD2, and the products from CD2 could be further degraded by CD1. These distinctions between the two domains enable them to synergize intramolecularly in alginate degradation, resulting in efficient and complete degradation of various alginate substrates. The bioinformatics analysis revealed that diverse alginate lyases have multiple catalytic domains, which are widespread, especially abundant in Flavobacteriaceae and Alteromonadales, which may secret multimodular alginate lyases for alginate degradation. This study provides new insight into bacterial alginate lyases and alginate degradation and is helpful for designing multimodular enzymes for efficient alginate depolymerization. IMPORTANCE Alginate is a major component in the cell walls of brown algae. Alginate degradation is carried out by alginate lyases. Until now, while most characterized alginate lyases contain one single catalytic domain, only a few have been shown to contain two catalytic domains. Furthermore, the synergy of alginate lyases has attracted increasing attention since it plays important roles in microbial alginate utilization and biotechnological applications. Although many studies have focused on the synergy between different alginate lyases, the synergy between two catalytic domains of one alginate lyase has not been reported. Here, a novel alginate lyase, AlyC6', with two functional alginate lyase domains was biochemically characterized. Moreover, the synergism between the two domains of AlyC6' was revealed. Additionally, the distribution of the alginate lyases with multiple alginate lyase domains was investigated based on the bioinformatics analysis. This study provides new insight into bacterial alginate lyases and alginate degradation.


Asunto(s)
Polisacárido Liasas , Vibrio , Secuencia de Aminoácidos , Polisacárido Liasas/metabolismo , Vibrio/metabolismo , Alginatos/metabolismo , Especificidad por Sustrato
7.
Blood ; 135(25): 2302-2315, 2020 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-32384137

RESUMEN

Erythropoiesis is a complex multistage process that involves differentiation of early erythroid progenitors to enucleated mature red blood cells, in which lineage-specific transcription factors play essential roles. Erythroid Krüppel-like factor (EKLF/KLF1) is a pleiotropic erythroid transcription factor that is required for the proper maturation of the erythroid cells, whose expression and activation are tightly controlled in a temporal and differentiation stage-specific manner. Here, we uncover a novel role of G-protein pathway suppressor 2 (GPS2), a subunit of the nuclear receptor corepressor/silencing mediator of retinoic acid and thyroid hormone receptor corepressor complex, in erythrocyte differentiation. Our study demonstrates that knockdown of GPS2 significantly suppresses erythroid differentiation of human CD34+ cells cultured in vitro and xenotransplanted in nonobese diabetic/severe combined immunodeficiency/interleukin-2 receptor γ-chain null mice. Moreover, global deletion of GPS2 in mice causes impaired erythropoiesis in the fetal liver and leads to severe anemia. Flow cytometric analysis and Wright-Giemsa staining show a defective differentiation at late stages of erythropoiesis in Gps2-/- embryos. Mechanistically, GPS2 interacts with EKLF and prevents proteasome-mediated degradation of EKLF, thereby increasing EKLF stability and transcriptional activity. Moreover, we identify the amino acids 191-230 region in EKLF protein, responsible for GPS2 binding, that is highly conserved in mammals and essential for EKLF protein stability. Collectively, our study uncovers a previously unknown role of GPS2 as a posttranslational regulator that enhances the stability of EKLF protein and thereby promotes erythroid differentiation.


Asunto(s)
Eritropoyesis/fisiología , Péptidos y Proteínas de Señalización Intracelular/fisiología , Factores de Transcripción de Tipo Kruppel/fisiología , Secuencia de Aminoácidos , Animales , Células Cultivadas , Secuencia Conservada , Células Precursoras Eritroides/citología , Técnicas de Silenciamiento del Gen , Trasplante de Células Madre Hematopoyéticas , Humanos , Subunidad gamma Común de Receptores de Interleucina/deficiencia , Péptidos y Proteínas de Señalización Intracelular/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Péptidos y Proteínas de Señalización Intracelular/genética , Factores de Transcripción de Tipo Kruppel/antagonistas & inhibidores , Factores de Transcripción de Tipo Kruppel/química , Hígado/embriología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Mapeo de Interacción de Proteínas , Procesamiento Proteico-Postraduccional , Estabilidad Proteica , Proteolisis , Interferencia de ARN , ARN Interferente Pequeño/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transcripción Genética , Trasplante Heterólogo , Ubiquitinación , Regulación hacia Arriba
8.
Inorg Chem ; 61(30): 11866-11878, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35857312

RESUMEN

Two isomorphic lanthanide compounds {[Ln(ddpp)(H2O)]·CH3CN}n (Ln = Eu and Gd, H4ddpp = 2,5-di(2',4'-dicarboxylphenyl)pyridine) were synthesized. Complex 1-Eu displays ultrahigh acid-base stability and thermal stability. Furthermore, luminescence measurements revealed that 1-Eu could detect quinolone antibiotics with an ultralow limit of detection in aqueous solution. The ratiometric probe properties for sensing antibiotics could be attributed to the incompletely sensitized Eu3+ ion of the ligand. Remarkably, it is interesting that 1-Gd exhibits excellent tetracycline degradation properties under visible light. Ultraviolet-visible diffuse reflectance spectroscopy and valence band X-ray photoelectron spectroscopy were carried out to investigate the photodegradation mechanisms. Moreover, a rational explanation for the fluorescent probe and photocatalysis behavior of these two complexes was also discussed with the assistance of density functional theory calculations.


Asunto(s)
Elementos de la Serie de los Lantanoides , Estructuras Metalorgánicas , Antibacterianos , Elementos de la Serie de los Lantanoides/química , Ligandos , Mediciones Luminiscentes/métodos
9.
Mikrochim Acta ; 188(7): 235, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34164747

RESUMEN

A heteropore covalent organic framework (COF)-based composite membrane material was prepared and proved to have a satisfactory effect on the pretreatment of vegetable samples. The composite membrane was fabricated by in situ growth of a dual-pore COF on the surface of polydopamine (PDA)-aminated non-woven (NW) fabric. Due to the difference in the strength of the interaction between the phytochromes/COF and the pesticides/COF, the removal of phytochromes and the recovery of pesticides can be achieved by adjusting the composition of the solution. Through a simple immersion or filtration operation, NW@PDA@COF composite membrane can quickly and almost completely remove interfering phytochromes in the samples. The recovery of pesticides was determined by HPLC-MS/MS, and the recovery efficiencies were 72.3~101.7% and 67.3~106.7% for immersion and filtration modes of five different vegetable samples, respectively; the RSD is between 1.1 and 19% (n = 3). The limits of detection and quantification for the 13 pesticides investigated were 0.08 µg·L-1 and 0.23 µg·L-1, respectively. A wide linear range of 1~1000 µg·L-1 was observed with R2 values from 0.9774 to 0.9998. The membrane can be repeatedly used for at least 10 times by using a facile elution treatment. Compared to other commonly used sample pretreatment materials, heteropore COF-based composite membrane is superior in terms of sorbent amount, treatment time, operation simplicity, and material reusability.

10.
J Autoimmun ; 108: 102404, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31952907

RESUMEN

The chromatin modifier enhancer of zeste homolog 2 (EZH2) methylates lysine 27 of histone H3 (H3K27) and regulates T cell differentiation. However, the potential role of EZH2 in the pathogenesis of rheumatoid arthritis (RA) remains elusive. We analyzed EZH2 expression in PBMC, CD4+ T cells, CD19+ B cell, and CD14+ monocytes from active treatment-naïve RA patients and healthy controls (HC). We also suppressed EZH2 expression using EZH2 inhibitor GSK126 and measured CD4+ T cell differentiation, proliferation and apoptosis. We further examined TGFß-SMAD and RUNX1 signaling pathways in EZH2-suppressed CD4+ T cells. Finally, we explored the regulation mechanism of EZH2 by RA synovial fluid and fibroblast-like synoviocyte (FLS) by neutralizing key proinflammatory cytokines. EZH2 expression is lower in PBMC and CD4+ T cells from RA patients than those from HC. EZH2 inhibition suppressed regulatory T cells (Tregs) differentiation and FOXP3 transcription, and downregulated RUNX1 and upregulated SMAD7 expression in CD4+ T cells. RA synovial fluid and fibroblast-like synoviocytes suppressed EZH2 expression in CD4+ T cells, which was partially neutralized by anti-IL17 antibody. Taken together, EZH2 in CD4+ T cells from RA patients was attenuated, which suppressed FOXP3 transcription through downregulating RUNX1 and upregulating SMAD7 in CD4+ T cells, and ultimately suppressed Tregs differentiation. IL17 in RA synovial fluid might promote downregulation of EZH2 in CD4+ T cells. Defective EZH2 in CD4+ T cells might contribute to Treg deficiency in RA.


Asunto(s)
Artritis Reumatoide/etiología , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Proteína Potenciadora del Homólogo Zeste 2/deficiencia , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Biomarcadores , Estudios de Casos y Controles , Citocinas/metabolismo , Histonas/metabolismo , Humanos , Mediadores de Inflamación/metabolismo , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Monocitos/inmunología , Monocitos/metabolismo , Líquido Sinovial/inmunología , Líquido Sinovial/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/citología
11.
J Autoimmun ; 107: 102360, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31806420

RESUMEN

OBJECTIVE: Gut dysbiosis has been reported implicated in ankylosing spondylitis (AS), a common chronic inflammatory disease mainly affects sacroiliac joints and spine. Utilizing deep sequencing on the feces of untreated AS patients, our study aimed at providing an in-depth understanding of AS gut microbiota. METHODS: We analyzed the fecal metagenome of 85 untreated AS patients and 62 healthy controls by metagenomic shotgun sequencing, and 23 post-treatment feces of those AS patients were collected for comparison. Comparative analyses among different cohorts including AS, rheumatoid arthritis and Behcet's disease were performed to uncover some common signatures related to inflammatory arthritis. Molecular mimicry of a microbial peptide was also demonstrated by ELISpot assay. RESULTS: We identified AS-enriched species including Bacteroides coprophilus, Parabacteroides distasonis, Eubacterium siraeum, Acidaminococcus fermentans and Prevotella copri. Pathway analysis revealed increased oxidative phosphorylation, lipopolysaccharide biosynthesis and glycosaminoglycan degradation in AS gut microbiota. Microbial signatures of AS gut selected by random forest model showed high distinguishing accuracy. Some common signatures related to autoimmunity, such as Bacteroides fragilis and type III secretion system (T3SS), were also found. Finally, in vitro experiments demonstrated an increased amount of IFN-γ producing cells triggered by a bacterial peptide of AS-enriched species, mimicking type II collagen. CONCLUSIONS: These findings collectively indicate that gut microbiota was perturbed in untreated AS patients with diagnostic potential, and some AS-enriched species might be triggers of autoimmunity by molecular mimicry. Additionally, different inflammatory arthritis shared some common microbial signatures.


Asunto(s)
Microbioma Gastrointestinal , Mediadores de Inflamación/metabolismo , Metagenoma , Metagenómica , Espondilitis Anquilosante/etiología , Espondilitis Anquilosante/metabolismo , Autoinmunidad , Estudios de Casos y Controles , Susceptibilidad a Enfermedades , Disbiosis , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno/inmunología , Humanos , Metagenómica/métodos , Espondilitis Anquilosante/patología
12.
Zhongguo Zhong Yao Za Zhi ; 45(13): 3112-3119, 2020 Jul.
Artículo en Zh | MEDLINE | ID: mdl-32726019

RESUMEN

The WRKY family genes, which play an important role in plant morphogenesis and stress response, were selected based on the data of the full-length transcriptome of Asarum heterotropoides. Using AtWRKY33, which regulates the synthesis of the camalexin in the model plant Arabidopsis to compare homologous genes in A. heterotropoides, primers were designed to amplify the open reading frame(ORF) fragment of AhWRKY33 gene by RT-PCR using total RNA of A. heterotropoides leaves as template. Real-time PCR results showed that there was a significant difference between the aerial part and the underground part of A. heterotropoides, the toxic aristolochic acid content is highly expressed in the leaves higher than the root. After verification, the WRKY33 gene of A. heterotropoides is ORF long 1 686 bp, encoding 561 amino acids.AhWRKY33 had two conserved WRKYGQK domains. According to the classical classification, it belongs to group Ⅰ WRKY transcription factor. A. heterotropoides WRKY33 had some homology with amino acids of other species. The study successfully constructed the plant eukaryotic expression vector PHG-AhWRKY33 and transformed Arabidopsis thaliana, the transgenic Arabidopsis was obtained by PCR detection and hygromycin resistant plate screening. It found that the germination of transgenic Arabidopsis seeds was accelerated and the stress resistance was increased. It laid a foundation for further analysis of WRKY transcription factor in the growth and development of A. heterotropoides and the synthesis of secondary metabolites.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Asarum , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta , Proteínas de Plantas/genética , Factores de Transcripción , Transformación Genética
13.
Zhongguo Zhong Yao Za Zhi ; 44(7): 1357-1362, 2019 Apr.
Artículo en Zh | MEDLINE | ID: mdl-31090292

RESUMEN

In this study, solid dispersion technology was used to develop volatile oil from Acorus tatarinowii self-nanoemulsion dropping pills(VOA-SNEDDS-DP) and its protective effect on acute myocardial ischemia injury was evaluated. Taking exterior quality, weight variation and the resolving time as comprehendsive evaluation indexes, the preparation process and formulation of the dropping pills were optimized by orthogonal design, and the dissolution rate in vitro of the optimized VOA-SNEDDS-DP was investigated. The rat model of acute myocardial ischemia was induced by intraperitoneal injection of isoproterenol hydrochloride and the serum levels of superoxide dismutase(SOD), malondialdehyde(MDA), creatine kinase(CK) and pathological changes of myocardial tissue were determined to evaluate therapeutic effect of the dropping pills on acute myocardial ischemia. The results showed that the optimal formulation and preparation process of VOA-SNEDDS-DP were as follows: PEG6000-PEG8000 was 1∶1, proportion of VOA-SNEDDS and matrix was l∶2.5, the temperature of drug fluids was 75 ℃, drop rate was 35 drops/min, drop distance was 5 cm, the condensing agent temperature was 2-10 ℃. The content of ß-asarone in the dropping pills was 42.46 mg·g~(-1). The accumulated dissolution rate of the dropping pills reached 93.85% in 10 min. The results of pharmacodynamic experiments showed that VOA-SNEDDS-DP could significantly increase the SOD content(P<0.05), reduce the levels of MDA and CK(P<0.05) in serum, and effectively improve the pathological morphology of myocardial tissue. These results revealed that the preparation of VOA-SNEDDS-DP by solid dispersion technology was stable and feasible, and VOA-SNEDDS-DP had protective effect on acute myocardial ischemia injury.


Asunto(s)
Acorus/química , Medicamentos Herbarios Chinos/farmacología , Isquemia Miocárdica/tratamiento farmacológico , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Animales , Creatina Quinasa/sangre , Malondialdehído/sangre , Ratas , Superóxido Dismutasa/sangre
14.
Zhongguo Zhong Yao Za Zhi ; 44(6): 1164-1169, 2019 Mar.
Artículo en Zh | MEDLINE | ID: mdl-30989979

RESUMEN

Herpetone( HPT) is a bioactive lignan extracted from Herpetospermum pedunculosum,which can protect liver,lower aminotransferase and inhibit hepatitis B virus. However,HPT has a poor oral bioavailability due to its poor water solubility. And there is no report about whether HPT has an anti-hepatic fibrosis activity. To improve the dissolution of HPT and study its anti-hepatic fibrosis activity and mechanism,the study group prepared herpetone nanosuspensions( HPT-NS) by the miniaturized media milling method. The formulation and process of HPT-NS were optimized by the single factor experiment. Scanning electron microscopy was used to observe morphology of HPT-NS. Dialysis method was used to study dissolution of HPT-NS in vitro. CCK8 method was used to assess the effect of HPT-NS on proliferation of the rat hepatic stellate cells( HSC-T6). Flow cytometry was used to assess the effect of HPT-NS on apoptosis and cell cycle of HSC-T6. The mean particle size of optimized HPT-NS was( 196±7) nm with a polydispersity index of 0.279±0.009.SEM showed that HPT-NS was in a regular rod shape. The cumulative dissolution rate of HPT-NS reached 93% in 18 h,and was higher than that of herpetone coarse suspensions( HPT-CS,28%). CCK8 experiment showed that the inhibition rate of HPT-NS on HSC-T6 was higher than that of HPT-CS. Flow cytometry showed that HPT-NS could block HSC-T6 cells in G2/M phase and induce apoptosis of HSC-T6 cells,with a significantly stronger effect than HPT-CS. The results revealed that HPT-NS significantly increased the in vitro dissolution of HPT,and enhanced the inhibitive effect on HSC-T6 cell proliferation by blocking cells in the G2/M phase and inducing late apoptosis.


Asunto(s)
Cirrosis Hepática , Animales , Línea Celular , Células Estrelladas Hepáticas , Lignanos , Ratas
15.
J Mol Recognit ; 31(5): e2691, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29210128

RESUMEN

Tremendous research efforts have been dedicated to fabricating high-quality Zn-doped CdTe quantum dots (QDs) for any potential biomedical applications. In particular, the correlation of issues regarding how QDs interact with DNA is of greatest importance. Herein, a pH-responsive study of the interactions between CdTe:Zn2+ quantum dots with 4 different sizes and calf thymus DNA (ctDNA) was conducted using multispectroscopic techniques and electrochemical investigation. Fluorescence studies revealed that this interaction process is predominantly a static process and groove binding was the main binding mode for CdTe:Zn2+ QDs to ctDNA. The calculated negative values of enthalpy (-45.06 kJ mol-1 ) and entropy (-133.62 J mol-1  K-1 ) with temperature changes indicated that the hydrogen bonds and van der Waals interactions played major roles in the reaction. Furthermore, circular dichroism spectroscopy and Fourier transform infrared spectrometry analyses indicate that the normal conformation of ctDNA is discombobulated by CdTe:Zn2+ QDs. In addition, the electrochemical behavior of the affinity of CdTe:Zn2+ QDs for ctDNA agreed well with the results obtained from fluorescence experiments. This study might be meaningful for understanding the molecular binding mechanism of QDs for DNA and provides a basis for QD-labeled systems.


Asunto(s)
Compuestos de Cadmio/síntesis química , ADN/química , Telurio/química , Zinc/química , Compuestos de Cadmio/química , Técnicas Electroquímicas , Enlace de Hidrógeno , Tamaño de la Partícula , Puntos Cuánticos , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
16.
Respirology ; 23(10): 950-955, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29691960

RESUMEN

BACKGROUND AND OBJECTIVE: Delayed diagnosis and treatment of tuberculosis (TB) contribute to poor outcomes, especially for endobronchial TB (EBTB), which typically leads to tracheobronchial stenosis. Finding rapid and accurate diagnostic tools for EBTB is crucial. GeneXpert Mycobacterium tuberculosis (MTB)/rifampin (RIF) was recommended by the World Health Organization (WHO) as a standard molecular biological diagnostic technique for MTB. The aim of this study was to evaluate the efficacy of GeneXpert MTB/RIF for diagnosing EBTB and for evaluating RIF resistance. METHODS: Biopsy tissue and bronchial brushings from EBTB patients were prospectively assessed with GeneXpert MTB/RIF. The diagnostic yields of auramine O-stained sputum smears and bronchial brush smears were obtained, and the results were compared with the cultures of sputum and biopsy tissues for MTB. RESULTS: In 61 confirmed cases of EBTB, the sensitivities of sputum smear, bronchial brush smear, sputum culture and tissue culture to diagnose EBTB were 13.1%, 32.8%, 36.1% and 68.9%, respectively. For bronchial brushings and biopsies, our data showed sensitivities of 57.4% and 63.9%, respectively, and a specificity of 100% for GeneXpert MTB/RIF, and these results were superior to those of sputum smears, bronchial brush smears and sputum culture. GeneXpert MTB/RIF for bronchial brushings and biopsies showed complementarity in its diagnostic performance. Resistance to RIF was identified in 17.4% (8/46) of GeneXpert MTB-positive cases. CONCLUSION: GeneXpert MTB/RIF may enable more rapid EBTB diagnosis and determination of RIF resistance, which are crucial for timely treatment.


Asunto(s)
Bronquios/patología , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/genética , Tuberculosis Pulmonar/diagnóstico , Adulto , Antibióticos Antituberculosos/farmacología , Biopsia , Farmacorresistencia Bacteriana/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rifampin/farmacología , Sensibilidad y Especificidad , Esputo/microbiología , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/patología , Adulto Joven
17.
Zhongguo Zhong Yao Za Zhi ; 43(8): 1626-1632, 2018 Apr.
Artículo en Zh | MEDLINE | ID: mdl-29751709

RESUMEN

Astilbil nanosuspension (AT-NS) was prepared by an antisolvent precipitation method. The formula and process of AT-NS were optimized by the single factor experiment. AT-NS was prepared under the optimal conditions, and its morphology and crystallinity were characterized. In vitro release of AT-NS was also determined. The particle size of AT-NS stabilized by PVP K30 was (149±3) nm, and the polydispersity index (PDI) and stability index (SI) were 0.137±0.014 and 0.940±0.012, respectively. The results of SEM showed that AT-NS was spherical. Both XRD and DSC showed that AT was amorphous in nanosuspension. In the in vitro release test, AT-NS showed a significantly increased dissolution. This simple low-cost approach could prepare AT-NS successfully. AT-NS could significantly improve the dissolution of AT and provide the reference to break the limitation on the clinical application of AT.


Asunto(s)
Flavonoles/química , Nanopartículas , Tamaño de la Partícula , Solubilidad , Suspensiones
18.
Zhongguo Zhong Yao Za Zhi ; 43(20): 4062-4068, 2018 Oct.
Artículo en Zh | MEDLINE | ID: mdl-30486531

RESUMEN

In order to increase the solubility of volatile oil from Acori Tatarinowii Rhizoma, this study was to prepare self-nanoemulsion of volatile oil from Acori Tatarinowii Rhizoma . The prescriptions were preliminarily screened by miscibility studies, excipient compatibility tests, and pseudo-ternary phase diagrams, and then the optimal formulation was obtained by using the Box-Behnken response surface method, with particle size and drug-loading rate as the indicators. The self-nanoemulsion prepared by optimal prescription was characterized and evaluated for in vitro dissolution. The results showed that the optimal prescription for this volatile oil self-nanoemulsion was as follows: 41.7% volatile oil, 46.8% Tween-80, and 11.5% PEG-400. The prepared self-nanoemulsion was clear and transparent, with drug-loading of (192.77±1.64) mg·g⁻¹, particle diameter of (53.20±0.94) nm, polydispersity index of 0.230± 0.013, and Zeta potential of (-12.2±0.7) mV. The in vitro dissolution of self-nanoemulsion was higher than that of volatile oil. In this research, volatile oil served as the oil phase in self-nanoemulsion, so the prescription was simpler and the drug loading rate was higher. The prepared self-nanoemulsion complied with the relevant quality requirements, providing a reference for the preparation of volatile oil formulations.


Asunto(s)
Acorus/química , Aceites Volátiles/normas , Aceites de Plantas/normas , Emulsiones , Aceites Volátiles/análisis , Tamaño de la Partícula , Aceites de Plantas/análisis , Rizoma/química , Solubilidad
19.
Sheng Li Xue Bao ; 69(5): 685-692, 2017 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-29063116

RESUMEN

Endocannabinoid receptor system is extensively expressed in the vertebrate retina. There are two types of cannabinoid receptors, CB1 and CB2. Activation of these two receptors by endocannabinoids N-arachidonoylethanolamide (anandamine, AEA) and 2-arachidonyl glycerol (2-AG) regulates multiple neuronal and glial ion channels, thus getting involved in retinal visual information processing. In this review, incorporating our results, we discuss the modulation of cannabinoid CB1 and CB2 receptors on retinal neuronal and glial ion channels and retinal synaptic transmission.


Asunto(s)
Canales Iónicos/fisiología , Receptores de Cannabinoides/fisiología , Retina/fisiología , Transmisión Sináptica/fisiología , Animales , Ácidos Araquidónicos/farmacología , Endocannabinoides/farmacología , Glicéridos/farmacología , Humanos , Alcamidas Poliinsaturadas/farmacología
20.
J Neurosci ; 35(13): 5409-21, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25834064

RESUMEN

EphB1, expressed in Müller cells, and ephrinB2, expressed in both Müller cells and retinal ganglion cells (RGCs), constitute an EphB/ephrinB reverse signaling in RGCs. Whether and how this reverse signaling is involved in RGC apoptosis in a rat chronic ocular hypertension (COH) model was investigated. In the COH model, both EphB1 and ephrinB2 were significantly increased and the reverse signaling was activated, which was accompanied by increased protein levels of phosphorylated (p) src, GluA2, and p-GluA2. Intravitreal injection of EphB2-Fc, an activator of ephrinB2, induced an increase in TUNEL-positive signals in normal retinae. A coimmunoprecipitation assay demonstrated direct interactions among ephrinB2, p-src, and GluA2. Moreover, in COH rats the expression of GluA2 proteins on the surface of retinal cells was decreased. Such GluA2 endocytosis could be prevented by preoperational intravitreal injection of 4-amino-3-(4-chlorophenyl)-1-(t-butyl)-1H-pyrazolo [3,4-d] pyrimidine (PP2), an inhibitor of src family tyrosine kinases, and possibly involved the protein interacting with C kinase 1 and phosphorylation of GluA2. In normal rats, intravitreal injection of EphB2-Fc caused changes in these protein levels similar to those observed in COH rats, which all could be avoided by preinjection of PP2. Patch-clamp experiments further showed that the current-voltage relationship of AMPA receptor-mediated EPSCs of RGCs exhibited stronger inward rectification in EphB2-Fc-injected rats. Furthermore, preinjection of PP2 or N-[3-[[4-[(3-aminopropyl)amino]butyl]amino]propyl]-1-naphthaleneacetamide trihydrochloride) (Naspm), a Ca(2+)-permeable GluA2-lacking AMPA receptor inhibitor, remarkably inhibited RGC apoptosis in either EphB2-Fc-injected or COH rats. Together, elevated GluA2 trafficking induced by activated EphB2/ephrinB2 reverse signaling likely contributes to RGC apoptosis in COH rats.


Asunto(s)
Apoptosis/fisiología , Efrina-B2/metabolismo , Hipertensión Ocular/metabolismo , Receptor EphB1/metabolismo , Receptores AMPA/metabolismo , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/fisiología , Transducción de Señal , Animales , Apoptosis/efectos de los fármacos , Modelos Animales de Enfermedad , Efrina-B2/agonistas , Potenciales Postsinápticos Excitadores , Etiquetado Corte-Fin in Situ , Masculino , Fosforilación , Transporte de Proteínas/efectos de los fármacos , Pirimidinas/farmacología , Ratas , Receptores AMPA/antagonistas & inhibidores , Células Ganglionares de la Retina/metabolismo , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/metabolismo
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