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1.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3725-3735, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-39099347

RESUMEN

Using Origin2022Pro, PAST4.09, GraphPad, and ArcGIS, this study analyzed the big data of the fourth national survey of traditional Chinese medicine resources in Jilin province from five dimensions: differences in resource quantity, taxonomic group, family, and genus, regional distribution, and spatiotemporal distribution, aiming to fully elucidate the biodiversity of medicinal plants in Jilin province. The results indicated that 2 241 species of medicinal plants existed in Jilin province, belonging to 881 genera of 243 families, with 20 dominant families and 3 dominant genera. There were 1 901 species of medicinal plants(belonging to 778 genera of 227 families) in the eastern mountainous region, 1 503 species(belonging to 690 genera of 225 families) in the mid-mountainous areas of the central mountainous region, and 811 species(belonging to 436 genera of 136 families) in the western plain region. The biodiversity of medicinal plants in Jilin province was high and presented a trend of high in the east and low in the west. The medicinal plant resources were mainly concentrated in the eastern mountainous region, and the number of medicinal plant groups had significant diffe-rences between regions, following the trend of western region > central region > eastern region. The species richness was in the order of eastern region > western region > central region. The species diversity structure in the central region was similar to that in the eastern and western regions, while it was significantly different between the western and eastern regions. Compared with the third national survey of traditional Chinese medicine resources, the fourth survey showed an increase of 1 417 species, a decrease of 580 species, and 824 common species, indicating significant changes in the biodiversity of medicinal plants in Jilin province. The reasons for these changes need to be further explored. This article elucidates the background and biodiversity changes of medicinal plant resources in Jilin province, laying a foundation for the protection, utilization, and industrial development of traditional Chinese medicine resources in Jilin province.


Asunto(s)
Biodiversidad , Medicina Tradicional China , Plantas Medicinales , Plantas Medicinales/química , Plantas Medicinales/clasificación , Plantas Medicinales/crecimiento & desarrollo , China , Encuestas y Cuestionarios
2.
Front Neurorobot ; 18: 1387428, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38765872

RESUMEN

The tactile object recognition (TOR) is highly important for environmental perception of robots. The previous works usually utilize single scale convolution which cannot simultaneously extract local and global spatiotemporal features of tactile data, which leads to low accuracy in TOR task. To address above problem, this article proposes a local and global residual (LGR-18) network which is mainly consisted of multiple local and global convolution (LGC) blocks. An LGC block contains two pairs of local convolution (LC) and global convolution (GC) modules. The LC module mainly utilizes a temporal shift operation and a 2D convolution layer to extract local spatiotemporal features. The GC module extracts global spatiotemporal features by fusing multiple 1D and 2D convolutions which can expand the receptive field in temporal and spatial dimensions. Consequently, our LGR-18 network can extract local-global spatiotemporal features without using 3D convolutions which usually require a large number of parameters. The effectiveness of LC module, GC module and LGC block is verified by ablation studies. Quantitative comparisons with state-of-the-art methods reveal the excellent capability of our method.

3.
Int J Mol Sci ; 24(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37176008

RESUMEN

AA9 lytic polysaccharide monooxygenases (LPMOs) are copper-dependent metalloenzymes that play a major role in cellulose degradation and plant infection. Understanding the AA9 LPMO mechanism would facilitate the improvement of plant pathogen control and the industrial application of LPMOs. Herein, via point mutation, we investigated the role of glycine 2 residue in cellulose degradation by Thermoascus aurantiacus AA9 LPMOs (TaAA9). A computational simulation showed that increasing the steric properties of this residue by replacing glycine with threonine or tyrosine altered the H-bonding network of the copper center and copper coordination geometry, decreased the surface charge of the catalytic center, weakened the TaAA9-substrate interaction, and enhanced TaAA9-product binding. Compared with wild-type TaAA9, G2T-TaAA9 and G2Y-TaAA9 variants showed attenuated copper affinity, reduced oxidative product diversity and decreased substrate Avicel binding, as determined using ITC, MALDI-TOF/TOF MS and cellulose binding analyses, respectively. Consistently, the enzymatic activity and synergy with cellulase of the G2T-TaAA9 and G2Y-TaAA9 variants were lower than those of TaAA9. Hence, the investigated residue crucially affects the catalytic activity of AA9 LPMOs, and we propose that the electropositivity of copper may correlate with AA9 LPMO activity. Thus, the relationship among the amino acid at position 2, surface charge and catalytic activity may facilitate an understanding of the proteins in AA9 LPMOs.


Asunto(s)
Cobre , Oxigenasas de Función Mixta , Oxigenasas de Función Mixta/metabolismo , Cobre/metabolismo , Polisacáridos/metabolismo , Celulosa/metabolismo , Oxidación-Reducción
4.
Front Microbiol ; 12: 743305, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34646258

RESUMEN

Streptococcus mutans (S. mutans), the prime pathogen of dental caries, can secrete glucosyltransferases (GTFs) to synthesize extracellular polysaccharides (EPSs), which are the virulence determinants of cariogenic biofilms. Ursolic acid, a type of pentacyclic triterpene natural compound, has shown potential antibiofilm effects on S. mutans. To investigate the mechanisms of ursolic acid-mediated inhibition of S. mutans biofilm formation, we first demonstrated that ursolic acid could decrease the viability and structural integrity of biofilms, as evidenced by XTT, crystal violet, and live/dead staining assays. Then, we further revealed that ursolic acid could compete with the inherent substrate to occupy the catalytic center of GTFs to inhibit EPS formation, and this was confirmed by GTF activity assays, computer simulations, site-directed mutagenesis, and capillary electrophoresis (CE). In conclusion, ursolic acid can decrease bacterial viability and prevent S. mutans biofilm formation by binding and inhibiting the activity of GTFs.

5.
Artículo en Inglés | MEDLINE | ID: mdl-32850722

RESUMEN

In Trichoderma reesei, carbon catabolite repression (CCR) significantly downregulates the transcription of cellulolytic enzymes, which is usually mediated by the zinc finger protein Cre1. It was found that there is a conserved region at the C-terminus of Cre1/CreA in several cellulase-producing fungi that contains up to three continuous S/T phosphorylation sites. Here, S387, S388, T389, and T390 at the C-terminus of Cre1 in T. reesei were mutated to valine for mimicking an unphosphorylated state, thereby generating the transformants Tr_Cre1S387V, Tr_Cre1S388V, Tr_Cre1T389V, and Tr_Cre1T390V, respectively. Transcription of cel7a in Tr_ Cre1S388V was markedly higher than that of the parent strain when grown in glucose-containing media. Under these conditions, both filter paperase (FPase) and p-nitrophenyl-ß-D-cellobioside (pNPCase) activities, as well as soluble proteins from Tr_Cre1S388V were significantly increased by up to 2- to 3-fold compared with that of other transformants and the parent strain. The results suggested that S388 is critical site of phosphorylation for triggering CCR at the terminus of Cre1. To our knowledge, this is the first report demonstrating an improvement of cellulase production in T. reesei under CCR by mimicking dephosphorylation at the C-terminus of Cre1. Taken together, we developed a precision engineering strategy based on the modification of phosphorylation sites of Cre1 transcription factor to enhance the production of cellulase in T. reesei under CCR.

6.
Brain Res Bull ; 164: 361-371, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32777257

RESUMEN

PURPOSE: Repeated methamphetamine (METH) administration in mice readily produces behavioural sensitization, but the underlying mechanisms remain elusive. The present research aimed to identify new targets affecting METH-induced behavioural sensitization. METHODS: We first established a mouse model of METH-induced behavioural sensitization. To characterize the animal model, we performed behavioural tests at different stages of behavioural sensitization and simultaneously detected changes in several neurotransmitters in the prefrontal cortex (PFC). Next, we perfromed RNA sequencing (RNA-seq) to screen new targets, which were subsequently and verified by RT-PCR and western blot. Finally, we confirmed the roles of the new targets in METH-induced behavioural sensitization by injection of overexpressed lentiviruses and further detected related protein levels by western blot and histological changes by haematoxylin and eosin (HE) staining. RESULTS: We successfully established a mouse model of METH-induced behavioural sensitization. The locomotor activities of the mice changed at different stages of sensitization, accompanied by changes in the levels of DA, 5-HT, GABA and glutamate. For RNA-seq analysis, we chose Fas as target, meanwhile, we chose GIT1 as target through literature. The detection of gene expression by RT-PCR indicated that METH-sensitized mice exhibited decreased levels of Fas, MEK1 and CREB and increased levels of Erk1/2 in the PFC. Western blot analysis revealed decreased Fas, GIT1, MEK1 and phosphorylated CREB levels and increased phosphorylated Erk1/2 levels in METH-sensitized mice. Injection of Fas and GIT1 injection showed that overexpression of Fas and GIT1 inhibited the induction of METH sensitization and reversed the changes in neurotransmitter levels and related protein levels, including MEK1, phosphorylated CREB and phosphorylated Erk1/2, in METH-sensitized mice. Overexpression of Fas and GIT1 also reduced histological lesions induced by METH. CONCLUSION: The findings indicated that the development of behavioural sensitization to METH may be mediated by Fas and GIT1 through the MEK1-Erk1/2-CREB pathway.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Sensibilización del Sistema Nervioso Central/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/administración & dosificación , Proteínas Activadoras de GTPasa/metabolismo , Metanfetamina/administración & dosificación , Corteza Prefrontal/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor fas/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Dopamina/metabolismo , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Autoadministración , Serotonina/metabolismo
7.
Biotechnol Biofuels ; 12: 244, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31636703

RESUMEN

BACKGROUND: Trichoderma reesei is widely used for cellulase production and accepted as an example for cellulase research. Cre1-mediated carbon catabolite repression (CCR) can significantly inhibit the transcription of cellulase genes during cellulase fermentation in T. reesei. Early efforts have been undertaken to modify Cre1 for the release of CCR; however, this approach leads to arrested hyphal growth and decreased biomass accumulation, which negatively affects cellulase production. RESULTS: In this study, novel fusion transcription factors (fTFs) were designed to release or attenuate CCR inhibition in cellulase transcription, while Cre1 was left intact to maintain normal hyphal growth. Four designed fTFs were introduced into the T. reesei genome, which generated several transformants, named Kuace3, Kuclr2, Kuace2, and Kuxyr1. No obvious differences in growth were observed between the parent and transformant strains. However, the transcription levels of cel7a, a major cellulase gene, were significantly elevated in all the transformants, particularly in Kuace2 and Kuxyr1, when grown on lactose as a carbon source. This suggested that CCR inhibition was released or attenuated in the transformant strains. The growth of Kuace2 and Kuxyr1 was approximately equivalent to that of the parent strain in fed-batch fermentation process. However, we observed a 3.2- and 2.1-fold increase in the pNPCase titers of the Kuace2 and Kuxyr1 strains, respectively, compared with that of the parent strain. Moreover, we observed a 6.1- and 3.9-fold increase in the pNPCase titers of the Kuace2 and Kuxyr1 strains, respectively, compared with that of Δcre1 strain. CONCLUSIONS: A new strategy based on fTFs was successfully established in T. reesei to improve cellulase titers without impairing fungal growth. This study will be valuable for lignocellulosic biorefining and for guiding the development of engineering strategies for producing other important biochemical compounds in fungal species.

8.
Chem Pharm Bull (Tokyo) ; 67(10): 1076-1081, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31406093

RESUMEN

Histone deacetylases (HDACs) are enzymes that play a key role in structural modification and gene expression. The overexpression of HDAC is associated with cancer, and thus inhibiting the enzyme could be an efficient cancer therapy. To discover new HDAC inhibitors (HDACis), we proposed an improved protocol combining a hierarchical pharmacophore search, molecular docking, and molecular dynamic simulations. The test results showed that the improved screening protocol effectively reduced the false-positive rates of drug-like chemicals. Based on the protocol, we obtained 16 hit compounds as potential HDACis from the Life Chemicals database. Enzyme inhibition experiments showed that two of the hit chemical compounds had HDAC-inhibitory effects. In vitro assays showed that Z165155756 could selectively inhibit the proliferation of cancer cells and specifically promoted apoptosis and induced G1/S phase arrest in A2780 cells. It may have potential therapeutic effects in ovarian cancer and is worthy of further investigation.


Asunto(s)
Antineoplásicos/análisis , Antineoplásicos/farmacología , Descubrimiento de Drogas , Inhibidores de Histona Desacetilasas/análisis , Inhibidores de Histona Desacetilasas/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Histona Desacetilasas/química , Histona Desacetilasas/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Relación Estructura-Actividad
9.
Appl Microbiol Biotechnol ; 103(14): 5739-5750, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31152202

RESUMEN

Auxiliary activity family 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) show significant synergism with cellulase in cellulose degradation. In recent years, there have been many reports on AA9 LPMOs; however, the identification of efficient and thermostable AA9 LPMOs with broad potential for industrial applications remains necessary. In this study, a new AA9 LPMO from Talaromyces cellulolyticus, named TcAA9A, was identified. An analysis of the oxidation products of phosphoric acid-swollen cellulose categorized TcAA9A as a type 3 AA9 LPMO, and TcAA9A exhibited a better synergistic effect with cellulase from Trichoderma reesei than what is seen with TaAA9A, a well-studied AA9 LPMO from Thermoascus aurantiacus. Two AA9 LPMOs were successfully expressed in T. reesei, and the transformants were named TrTcAA9A and TrTaAA9A. The activities and thermostabilities of the AA9 LPMOs in TrTcAA9A were higher than those of the AA9 LPMOs in TrTaAA9A or the parent. The enzyme solution of TrTcAA9A was more efficient than that of the parent or TrTaAA9A for the degradation of Avicel and delignified corncob residue. Thus, TcAA9A showed a better performance than TaAA9A in T. reesei cellulase cocktails. This study may offer an innovative solution for improving enzyme cocktail activity for lignocellulosic degradation.


Asunto(s)
Proteínas Fúngicas/metabolismo , Lignina/metabolismo , Oxigenasas de Función Mixta/metabolismo , Polisacáridos/metabolismo , Thermoascus/enzimología , Celulasa/metabolismo , Celulosa/metabolismo , Estabilidad de Enzimas , Oxidación-Reducción , Temperatura , Trichoderma/metabolismo
10.
Sci Rep ; 9(1): 2350, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30787420

RESUMEN

Histone deacetylases (HDACs) can enzymatically transferred acetyl functional group from protein or lysine residues of histone, so they can regulate the expression of lots of genes. Now HDACs are used as drug targets and many HDAC inhibitors (HDACis) were approved for cancer therapy or in clinical trials. However, the physiological mechanisms and regulatory processes of HDACi anti-cancer effects are largely unexplored and uncompleted. Here we use the virtual screening workflow obtained 25 hit compounds and ZINC24469384 can significantly inhibit HDAC activity while arrest cell cycle at G1/S phase and significantly induced HepG2 cell apoptosis, time-course RNA-seq demonstrate that HepG2 cells transcriptionally respond to ZINC24469384. Pathway analysis of DEGs and DASGs reveal that NR1H4 may play an important role in ZINC24469384-induced anti-proliferation effect and is dramatically alleviated by down-regulating the SOCS2 expression and promoting STAT3 phosphorylation in knockdown NR1H4 HepG2 cells. Analysis based on TCGA database indicated that NR1H4 and SOCS2 were downregulated in liver cancer, this suggest NR1H4 and SOCS2 may play an important role in tumorigenesis. These results indicated that ZINC24469384 is a novel benzamine lead compound of HDACi and provides a novel mechanism for HDACi to inhibit cancer.


Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Inhibidores de Histona Desacetilasas/metabolismo , Humanos , Fosforilación , Factor de Transcripción STAT3/metabolismo , Activación Transcripcional/efectos de los fármacos
11.
Zhongguo Zhong Yao Za Zhi ; 44(24): 5368-5374, 2019 Dec.
Artículo en Chino | MEDLINE | ID: mdl-32237382

RESUMEN

The study is aimed to clarify the spatial distribution of Epimedium koreanum( Ek) high-quality production areas. Through visiting and field investigation,collecting the distribution information of Ek samples,and based on the four kinds of flavonoids in Ek,the high-quality production areas and distribution of Ek distribution of the main environmental factors were drawn using GIS technology,the maximum entropy model( MaxEnt),geographical detector statistical analysis method,and the statistical significance of regression equation were obtained. Considering the content of 4 main flavonoids in Ek,the results of this study showed that the main environmental factors,such as precipitation,annual precipitation variation coefficient,annual average temperature and clay content exhibited the greatest influence on the growth suitability of Ek. Ek materials quality concentrated distribution in southeastern Jilin province Changbai mountain hinterland and northeastern Liaoning province. Ek with high content of epimedine A and epimedine C are mainly distributed in the southeastern Jilin province and northeastern Liaoning province,Ek with high epimedine B is distributed in eastern Liaoning province; high icariin Ek was found in most area of northeastern Liaoning province,a small amount distributed in the southeast of Jilin province. This study predicted the climate suitability distribution of Ek,and provided reference for the rational planning and establishment of the standardized cultivation base of Ek.


Asunto(s)
Clima , Epimedium/química , Flavonoides/análisis , China , Medicamentos Herbarios Chinos , Geografía , Plantas Medicinales/química , Suelo/química , Temperatura
12.
Front Microbiol ; 8: 1738, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28955316

RESUMEN

Streptococcus mutans has been reported as a primary cariogenic pathogen associated with dental caries. The bacteria can produce glucosyltransferases (Gtfs) to synthesize extracellular polysaccharides (EPSs) that are known as virulence factors for adherence and formation of biofilms. Therefore, an ideal inhibitor for dental caries is one that can inhibit planktonic bacteria growth and prevent biofilm formation. Bergenia crassifolia (L.), widely used as a folk medicine and tea beverage, has been reported to have a variety of bioactivities. The present study aimed to explore the effect of B. crassifolia (L.) leaf extracts on the biofilm of Streptococcus mutans. The B. crassifolia (L.) leaf extracts showed inhibitory effects by decreasing viability of bacteria within the biofilm, as evidenced by the XTT assay, live/dead staining assay and LDH activity assay, and could decrease the adherence property of S. mutans through inhibiting Gtfs to synthesize EPSs. In addition, the reduced quantity of EPSs and the inhibition of Gtfs were positively correlated with concentrations of test samples. Finally, the MTT assay showed that the extracts had no cytotoxicity against normal oral cells. In conclusion, the extracts and sub-extracts of B. crassifolia leaves were found to be antimicrobial and could reduce EPS synthesis by inhibiting activities of Gtfs to prevent bacterial adhesion and biofilm formation. Therefore, B. crassifolia leaves have potential to be developed as a drug to prevent and cure dental caries.

13.
Zhongguo Zhong Yao Za Zhi ; 42(22): 4408-4413, 2017 Nov.
Artículo en Chino | MEDLINE | ID: mdl-29318843

RESUMEN

This paper is aims to clarify the spatial distribution of high quality medicinal materials Schisandrae Chinensis Fructus. Based on investigation and field investigation, the samples and distribution information of Schisandrae Chinensis Fructus were collected. Based on the data of four kinds of lignin chemical constituents, ecological environment factors and spatial distribution data of Schisandrae Chinensis Fructus, using GIS technology, maximum information entropy model and SPSS statistical analysis method for regionalizing the quality of Schisandrae Chinensis Fructus. The results showed that Schisandrae Chinensis Fructus was mainly distributed in the northeast of Liaoning, east of Jilin, east of Heilongjiang. The content of schisandrin was higher in the samples from northeastern part of Jilin province and the northeastern part of Liaoning province, The content of deoxyschizandrin was higher in the samples from middle of Jilin province and northeastern Hebei province, where the content of schisandrin B was higher in the samples from Jilin area, The higher schisantherin A sample were from southeast of Jilin and northeast of Liaoning. Considering the content of four components in Schisandrae Chinensis Fructus, the quality of Schisandrae Chinensis Fructus was concentrated in the southeast of Jilin and the northeastern part of Liaoning.


Asunto(s)
Medicamentos Herbarios Chinos/normas , Sistemas de Información Geográfica , Schisandra/química , China , Frutas/química , Plantas Medicinales/química , Control de Calidad
14.
Yao Xue Xue Bao ; 46(10): 1221-4, 2011 Oct.
Artículo en Chino | MEDLINE | ID: mdl-22242454

RESUMEN

The study on the buds of Jasminum officinale L. var. grandiflorum was carried out to look for anti-HBV constituents. The isolation and purification were performed by HPLC and chromatography on silica gel, polyamide and Sephadex LH-20 column. The structures were elucidated on the basis of physicochemical properties and spectral analysis. Six iridoid glycosides were identified as jasgranoside B (1), 6-O-methy-catalpol (2), deacetyl asperulosidic acid (3), aucubin (4), 8-dehydroxy shanzhiside (5), and loganin (6). Jasgranoside B (1) is a new compound. Compounds 2-6 were isolated from Jasminum officinale L. var. grandiflorum for the first time.


Asunto(s)
Glucósidos/aislamiento & purificación , Glicósidos Iridoides/aislamiento & purificación , Jasminum/química , Plantas Medicinales/química , Antivirales/química , Antivirales/aislamiento & purificación , Antivirales/farmacología , Flores/química , Glucósidos/química , Glucósidos/farmacología , Células Hep G2 , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/inmunología , Humanos , Concentración 50 Inhibidora , Glucósidos Iridoides/química , Glucósidos Iridoides/aislamiento & purificación , Glicósidos Iridoides/química , Glicósidos Iridoides/farmacología , Iridoides/química , Iridoides/aislamiento & purificación , Estructura Molecular
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