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1.
Community Ment Health J ; 56(5): 786-792, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32378126

RESUMO

This article describes a peer support project developed and carried out by a group of experienced mental health professionals, organized to offer peer psychological support from overseas to healthcare professionals on the frontline of the COVID-19 outbreak in Wuhan, China. This pandemic extremely challenged the existing health care systems and caused severe mental distress to frontline healthcare workers. The authors describe the infrastructure of the team and a novel model of peer support and crisis intervention that utilized a popular social media application on smartphone. Such a model for intervention that can be used elsewhere in the face of current global pandemic, or future disaster response.


Assuntos
Infecções por Coronavirus/psicologia , Intervenção em Crise/métodos , Pessoal de Saúde/psicologia , Saúde Ocupacional , Grupo Associado , Pneumonia Viral/psicologia , Mídias Sociais , Apoio Social , Austrália , COVID-19 , Canadá , China , Humanos , Cooperação Internacional , Saúde Mental , Aplicativos Móveis , Pandemias , Smartphone , Estados Unidos
2.
J Nanosci Nanotechnol ; 17(1): 370-6, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29620837

RESUMO

Magnetic Fe(3)O(4) nanoparticles were prepared through hydrothermal method and coated with silica on the surface to obtain Fe3O4@SiO2 core­shell nanoparticles. After modification with different functional groups including aldehyde, amine and diimide, the nanoparticles were used as carrier for covalent immobilization of lipase. The nanoparticles with aldehyde groups showed highest immobilization yield (52.8%) and efficiency (86.5%). And the immobilization conditions including pH, temperature and the concentration of enzyme were optimized. After immobilization, the K m of lipase was altered from 2.3 to 3.2 mM. The thermal stability and pH stability were enhanced by immobilization at the investigated conditions: pH 5.0­8.0 and temperature 30­70 °C. After 10 batches conversion of 4-Nitrophenyl palmitate into p-Nitrophenol, the immobilized lipase retained over 75% of the original activity. Compared with the commercial lipase Novozym435, the immobilized lipase showed better stability and higher catalytic efficiency. These results demonstrate that the immobilized lipase on the modified Fe3O4@SiO2 magnetic nanoparticles has enhanced stability and reusability, which make lipase of potential interest in a number of industrial applications.


Assuntos
Enzimas Imobilizadas/química , Lipase/química , Nanopartículas de Magnetita/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Propriedades de Superfície , Temperatura
3.
BMC Genomics ; 17: 113, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26878846

RESUMO

BACKGROUND: Hickory (Carya cathayensis Sarg.) accumulates more than 70% oil and 90% unsaturated fatty acids with considerably high oleic acid in its mature embryo. The concurrent global trancriptomic and lipidomic analyses provided a framework for better understanding of glycerolipid biosynthesis and metabolism in the hickory nut. RESULTS: The synthetical regulation of numerous leading lipid-related genes harmonized with the oil accumulation and fatty acid conversion in embryo development. The high level of ACCase correlated positively with fatty acids de novo synthesis, and the synergy of DGAT2 and PDAT promoted the TAG assembly, and oleosins, caleosins and steroleosins were transcribed considerably high for timely energy reserve in oil body. Glycolysis possibly provided sufficient precursors and energy for lipid synthesis. The perfect harmonization of the high level of SAD with low level of FAD2 facilitated the oleic acid accumulation. And the ratio of FATA/FATB or SAD/FATB was proposed for determining the saturated degree of oil. The gene multi-copy event was generated probably for accommodating various survival environments. A thermotolerant defense system including TAG hydrolysis determinants, heat shock proteins, and high ratio of MUFA to PUFA constrained the lipid degradation and provided a guarantee for high lipid content. A batch of potential genes recruited from the co-expression network helps us to understand the lipid synthesis and the response to high temperature better. CONCLUSIONS: The high transcriptional levels of key genes in lipid synthesis promoted the oil accumulation, and the harmonious expression of key ones for unsaturated fatty acids led oleic acid to high levels.


Assuntos
Carya/genética , Carya/metabolismo , Desenvolvimento Embrionário , Perfilação da Expressão Gênica , Metabolismo dos Lipídeos , Ácido Oleico/metabolismo , Óleos de Plantas/metabolismo , Desenvolvimento Embrionário/genética , Ácidos Graxos/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Glicólise , Metabolismo dos Lipídeos/genética , Lipídeos/biossíntese , Fenótipo , Sementes/embriologia , Sementes/genética , Transcrição Gênica , Transcriptoma
4.
Brief Bioinform ; 15(2): 306-18, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23271157

RESUMO

The capacity of apomixis to generate maternal clones through seed reproduction has made it a useful characteristic for the fixation of heterosis in plant breeding. It has been observed that apomixis displays pronounced intra- and interspecific diversification, but the genetic mechanisms underlying this diversification remains elusive, obstructing the exploitation of this phenomenon in practical breeding programs. By capitalizing on molecular information in mapping populations, we describe and assess a statistical design that deploys linkage analysis to estimate and test the pattern and extent of apomictic differences at various levels from genotypes to species. The design is based on two reciprocal crosses between two individuals each chosen from a hermaphrodite or monoecious species. A multinomial distribution likelihood is constructed by combining marker information from two crosses. The EM algorithm is implemented to estimate the rate of apomixis and test its difference between two plant populations or species as the parents. The design is validated by computer simulation. A real data analysis of two reciprocal crosses between hickory (Carya cathayensis) and pecan (C. illinoensis) demonstrates the utilization and usefulness of the design in practice. The design provides a tool to address fundamental and applied questions related to the evolution and breeding of apomixis.


Assuntos
Apomixia/genética , Plantas/genética , Algoritmos , Cruzamento , Carya/genética , Biologia Computacional , Ligação Genética , Variação Genética , Modelos Genéticos , Modelos Estatísticos , Fenômenos Fisiológicos Vegetais
5.
J Nanosci Nanotechnol ; 15(5): 3710-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26504996

RESUMO

The present study was designed to evaluate the biocompatibility of nanoparticles polyethylene glycol (PEG)-poly L-lysine (PLL)-poly lactic-co-glycolic acid copolymer (PLGA) (PEG-PLL-PLGA) before clinical application. We applied some tests to assess the safety of PEG-PLL-PLGA nanoparticles (NPs). There was low cytotoxicity of PEG-PLL-PLGA NPs in vitro as detected by MTT assay. Cell apoptosis and intracellular accumulation of PEG-PLL-PLGA were determined by FCM assay. The apoptotic rate induced by nanoparticles and the fluorescence intensity of intracellular daunorubicin (DNR) demonstrated that DNR-PEG-PLL-PLGA could be taken up by the mouse fibroblast cells (L929 cells). Hemolysis test and micronucleus (MN) assay demonstrated that the nanoparticles have no obviously blood toxicity and genotoxicity. DNR-PEG-PLL-PLGA NPs were injected into mice through tail vein to calculate the median lethal dose (LD50), the results showed that they had a wide safe scale. Blood was taken by removing the eyeball of mice to study the influence of DNR-PEG-PLL-PLGA in hepatic and renal functions. The results revealed that there was no significant difference as compared with the control group. Interestingly, the pathologic changes of heart, liver, spleen, lung and kidney were observed in nanoparticles treated mice. Thus, this study demonstrates that PEG-PLL-PLGA NPs appear to be highly biocompatible and safe nanoparticles that can be suitable for further application in the treatment of tumor.


Assuntos
Materiais Biocompatíveis , Nanopartículas , Poliésteres , Polietilenoglicóis , Polilisina , Animais , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Feminino , Hemólise/efeitos dos fármacos , Dose Letal Mediana , Masculino , Teste de Materiais , Camundongos , Nanopartículas/química , Nanopartículas/toxicidade , Nanotecnologia , Poliésteres/química , Poliésteres/toxicidade , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Polilisina/química , Polilisina/toxicidade , Coelhos
6.
Curr Genomics ; 15(5): 357-79, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25435799

RESUMO

Hickory (Carya cathayensis Sarg.), an important nut-producing species in Southeastern China, has high economic value, but so far there has been no cultivar bred under species although it is mostly propagated by seeding and some elite individuals have been found. It has been found recently that this species has a certain rate of apomixis and poor knowledge of its genetic background has influenced development of a feasible breeding strategy. Here in this paper we first release SSR (Simple sequence repeat) markers developed in this species and their transferability to other three species of the same genus, Carya. A total of 311 pairs of SSR primers in hickory were developed based on sequenced cDNAs of a fruit development-associated cDNA library and RNA-seq data of developing female floral buds and could be used to distinguish hickory, C. hunanensis Cheng et R. H. Chang ex R. H. Chang et Lu, C. illinoensis K. Koch (pecan) and C. dabieshanensis M. C. Liu et Z. J. Li, but they were monomorphic in both hickory and C. hunanensis although multi-alleles have been identified in all the four species. There is a transferability rate of 63.02% observed between hickory and pecan and the markers can be applied to study genetic diversity of accessions in pecan. When used in C. dabieshanensis, it was revealed that C. dabieshanensis had the number of alleles per locus ranging from 2 to 4, observed heterozygosity from 0 to 0.6667 and expected heterozygosity from 0.333 to 0.8667, respectively, which supports the existence of C. dabieshanensis as a separate species different from hickory and indicates that there is potential for selection and breeding in this species.

7.
Nat Prod Res ; : 1-6, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38230560

RESUMO

Isoquercitrin has superior in vivo bioactivities with respect to its primary glycoside rutin. Its conventional preparation was ineffective, with large chemical consumption and many by-products. Rhamnose, a high value-added monosaccharide, is usually separated from acid hydrolytes of rutin. This study aimed to establish a novel enzymatic hydrolysis-based approach for their preparation. α-L-rhamnosidase was expressed in Pichia pastoris GS115 and applied to enzymolysis of rutin. Then, one-factor-at-a-time optimisation of hydrolysis conditions was performed. Two compounds were produced in 0.02 M HAc-NaAc buffer (pH4.50) containing α-L-rhamnosidase/rutin (1:4, w/w) at 60 °C. Consequently, 20.0 g/L rutin was completely hydrolysed in 2 hrs, and isoquercitrin was obtained after purification by HPD-100 resin. Additionally, rhamnose was enriched by decolorisation and crystallisation. MD simulation analysis suggested that rutin was catalysed on the hydrophobic surface of r-Rha1 with van-der-Waals force being main driving force. This strategy is an efficient approach for preparation of isoquercitrin and rhamnose.

8.
Nat Prod Res ; 37(9): 1421-1428, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34866518

RESUMO

Prosapogenin A is a secondary saponin in Dioscorea zingiberensis, and it showed remarkable pharmacological effects. Due to very low content and lack of well-developed biotransformation, its preparation was not efficient and clean. This study aims to establish an eco-friendly strategy for preparation of Prosapogenin A from plant material. Physical separation was employed to recycle starch and cellulose, and then D101 resin and polyamide packed-bed column was incorporated for purification of total steroidal saponins (TSS). After these pretreatments, purity of TSS was largely increased to 83.2% with recovery at 87.6%, which was subjected to enzymatic hydrolysis. Optimized reaction system was constructed in 0.20 M HAc-NaAc buffer (pH4.2) containing cellulase/TSS (3:1, w/w), and the hydrolysis was performed at 53 °C for 6 h. Consequently, TSS was almost completely hydrolyzed to Prosapogenin A, while the highest yield reached 5.62%. The newly proposed approach is promising for efficient preparation of Prosapogenin A in industrial applications.


Assuntos
Dioscorea , Saponinas , Hidrólise , Saponinas/farmacologia , Biotransformação
9.
J Nat Med ; 77(4): 939-952, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37329418

RESUMO

Improving physiological activity of primary ginsenosides through biotransformation is of great significance for food applications. In this study, gynostapenoside XVII, gynostapenoside LXXV, ginsenoside F2, and ginsenoside CK were obtained by enzymolysis of an accessible extract composed of ginsenoside Rb1 and Rd. Their effects on melanin content and tyrosinase activity were compared in vitro, and molecular docking simulation was employed to elucidate the interaction between tyrosinase and individual saponin. The results indicated that four rare ginsenosides decreased tyrosinase activity, melanin content and microphthalmia-associated transcription factor (MITF) expression level, more greatly than their primary ginsenosides, and they were more readily to bind with ASP10 and GLY68 at active site of tyrosinase to inhibit tyrosinase activity as well. These findings suggested that the rare ginsenosides obtained by enzymolysis had excellent anti-melanogenic effect, which could expand the application of ginsenosides in the field of functional foods and health supplements.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/farmacologia , Ginsenosídeos/química , Ginsenosídeos/metabolismo , Melaninas/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Simulação de Acoplamento Molecular , Panax/química , Biotransformação
10.
Int J Biol Macromol ; 245: 125485, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348585

RESUMO

Abundant starch was isolated from Dioscorea zingiberensis C.H. Wright, a novel and underutilized industrial crop resource. In this study, an intelligent packaging film able to indicate food freshness was developed and characterized. D. zingiberensis starch (DZS) was bleached first, and its particle size, total starch content, amylose content, and gelatinization temperature were then measured. Butterfly pea (Clitoria ternatea Linn.) flowers were selected as the source of polyphenols, which rendered the prepared film intelligent and progressively blue-violet. SEM and FT-IR analyses showed the homogeneous dispersion of butterfly pea flower extract (BPE) in the film. The BPE-loaded film showed improved flexibility and resistance to UV and oxidation while maintaining sufficient mechanical strength and physical properties. Moreover, the film underwent a distinguishable color change from red to blue-violet and finally to green-yellow with increasing pH from 2 to 13. Similar color alteration also occurred when the film was exposed to ammonia. When the film was used to monitor the freshness of chicken stored at room temperature, it exhibited an obvious color change, implying its deterioration. Therefore, the newly developed BPE-DZS film, which was produced from readily accessible natural substances, can serve as an intelligent packaging material, indicating food freshness and prolonging shelf life.


Assuntos
Dioscorea , Amido , Amido/química , Antocianinas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Embalagem de Alimentos , Carne , Concentração de Íons de Hidrogênio
11.
Food Chem ; 381: 132281, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121314

RESUMO

Probiotic fermentation suspension was used to extend the shelf life of freshly cut lotus root for the first time, which played a dual role of biological protection and quality maintenance. Fermentation suspension contained lactic acid bacteria (8-9 log CFU/mL) was prepared from juice of lotus root and used to immerse samples under atmospheric pressure and vacuum. Probiotic fermentation suspension inhibited microorganism and the activity of polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonia lyase (PAL), which slowed down the physiological reaction and was beneficial to maintain the color and hardness of tissues. Lactic acid bacteria antagonized other microorganisms, and metabolic acid production played a continuous role in preservation during storage. The vacuum was helpful for the fermentation suspension to be fully impregnated into samples. The probiotic fermentation suspension had a significant inhibitory effect on E.coli O157:H7, and extended lotus root shelf life from 3 to 9 days.


Assuntos
Escherichia coli O157 , Microbiologia de Alimentos , Qualidade dos Alimentos , Lotus/microbiologia , Probióticos , Contagem de Colônia Microbiana , Fermentação , Raízes de Plantas/microbiologia , Vácuo
12.
Int J Biol Macromol ; 212: 20-30, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35597375

RESUMO

In this study, abundant starch was separated from the industrial crop Dioscorea zingiberensis C.H. Wright (DZW), and a novel bioactive packaging film loaded with oregano essential oil (OEO) was prepared and characterized. NaClO solution worked as a bleacher to prepare uniform starch powder from DZW tubers. OEO was selected from among three essential oils of Labiatae family plants for its strongest antibacterial activity. After the addition of OEO into the starch-based film, the UV-vis shielding property and antioxidant activity were enhanced. Meanwhile, the films still have a considerable performance in transparency, mechanical strength and water vapor permeability after incorporated with OEO. Furthermore, the 3% OEO-loaded starch film exhibited the strongest antibacterial activity against Bacillus subtilis, Escherichia coli and Staphylococcus aureus. It effectively lowered the total viable count of fresh chicken under 4 °C preservation conditions. These results revealed that the OEO-loaded DZW starch film can exert a positive effect on maintaining the quality and extending the shelf life of fresh meat. Therefore, readily accessible DZW tubers and oregano are very promising resources for application in degradable bioactive packaging film.


Assuntos
Dioscorea , Óleos Voláteis , Origanum , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Galinhas , Escherichia coli , Embalagem de Alimentos/métodos , Óleos Voláteis/farmacologia , Amido
13.
Tree Physiol ; 42(3): 684-702, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34409460

RESUMO

Hickory (Carya cathayensis Sarg.) is an extraordinary nut-bearing deciduous arbor with high content of oil in its embryo. However, the molecular mechanism underlying high oil accumulation is mostly unknown. Here, we reported that the lipid droplets and oil accumulation gradually increased with the embryo development and the oil content was up to ~76% at maturity. Furthermore, transcriptome and proteome analysis of developing hickory embryo identified 32,907 genes and 9857 proteins. Time-series analysis of gene expressions showed that these genes were divided into 12 clusters and lipid metabolism-related genes were enriched in Cluster 3, with the highest expression levels at 95 days after pollination (S2). Differentially expressed genes and proteins indicated high correlation, and both were enriched in the lipid metabolism. Notably, the genes involved in biosynthesis, transport of fatty acid/lipid and lipid droplets formation had high expression levels at S2, while the expression levels of other genes required for suberin/wax/cutin biosynthesis and lipid degradation were very low at all the sampling time points, ultimately promoting the accumulation of oil. Quantitative reverse-transcription PCR analysis also verified the results of RNA-seq. The co-regulatory networks of lipid metabolism were further constructed and WRINKLED1 (WRI1) was a core transcriptional factor located in the nucleus. Of note, CcWRI1A/B could directly activate the expression of some genes (CcBCCP2A, CcBCCP2B, CcFATA and CcFAD3) required for fatty acid synthesis. These results provided in-depth evidence for revealing the molecular mechanism of high oil accumulation in hickory embryo.


Assuntos
Carya , Carya/genética , Carya/metabolismo , Ácidos Graxos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteoma/genética , Proteoma/metabolismo , Sementes/genética , Sementes/metabolismo , Transcriptoma
14.
Food Chem ; 370: 130975, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34507207

RESUMO

Hickory (Carya cathayensis) nuts contain higher amount of lipids, and possess high nutritional value and substantial health benefits. However, their lipid composition and dynamic changes during embryogenesis have not been thoroughly investigated. Therefore, lipidomics profile and lipid dynamic changes during embryonic development were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Totally, 544 kinds of lipids were identified in mature hickory nuts with higher proportions of glycerolipids (59.94%) and glycerophospholipids (38.66%). Notably, diacylglycerols showed gradual uptrends, which corresponded with total glycerolipid and glycerophospholipid at middle and late stage of embryogenesis, suggesting the pivotal role of diacylglycerols in the accumulation of glycerolipids and glycerophospholipids. Moreover, triacylglycerols, diacylglycerols, phosphatidylethanolamines and phosphatidylcholines had high relative content with abundance of unsaturated fatty acids, specifically oleic acid, linoleic acid and linolenic acid, localized mainly at sn-2 lipid position. Together, our study provides innovative perspectives for studying the nutritional benefits of hickory nut lipids.


Assuntos
Carya , Cromatografia Líquida , Desenvolvimento Embrionário , Lipidômica , Nozes , Ácido Oleico , Espectrometria de Massas em Tandem
15.
Front Plant Sci ; 13: 990064, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36407576

RESUMO

Carya, in the Juglandiodeae subfamily, is to a typical temperate-subtropical forest-tree genus for studying the phylogenetic evolution and intercontinental disjunction between eastern Asia (EA) and North America (NA). Species of the genus have high economic values worldwide for their high-quality wood and the rich healthy factors of their nuts. Although previous efforts based on multiple molecular markers or genome-wide SNPs supported the monophyly of Carya and its two EA and NA major subclades, the maternal phylogeny of Carya still need to be comprehensively evaluated. The variation of Carya plastome has never been thoroughly characterized. Here, we novelly present 19 newly generated plastomes of congeneric Carya species, including the recently rediscovered critically endangered C. poilanei. The overall assessment of plastomes revealed highly conservative in the general structures. Our results indicated that remarkable differences in several plastome features are highly consistent with the EA-NA disjunction and showed the relatively diverse matrilineal sources among EA Carya compared to NA Carya. The maternal phylogenies were conducted with different plastome regions and full-length plastome datasets from 30 plastomes, representing 26 species in six genera of Juglandoideae and Myrica rubra (as root). Six out of seven phylogenetic topologies strongly supported the previously reported relationships among genera of Juglandoideae and the two subclades of EA and NA Carya, but displayed significant incongruencies between species within the EA and NA subclades. The phylogenetic tree generated from full-length plastomes demonstrated the optimal topology and revealed significant geographical maternal relationships among Carya species, especially for EA Carya within overlapping distribution areas. The full-length plastome-based phylogenetic topology also strongly supported the taxonomic status of five controversial species as separate species of Carya. Historical and recent introgressive hybridization and plastid captures might contribute to plastome geographic patterns and inconsistencies between topologies built from different datasets, while incomplete lineage sorting could account for the discordance between maternal topology and the previous nuclear genome data-based phylogeny. Our findings highlight full-length plastomes as an ideal tool for exploring maternal relationships among the subclades of Carya, and potentially in other outcrossing perennial woody plants, for resolving plastome phylogenetic relationships.

16.
Mitochondrial DNA B Resour ; 6(3): 1044-1049, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33796733

RESUMO

A triplex PCR assay was developed to identify animal species and adulteration of a natural medicine Galli Gigerii Endothelium Corneum (GGEC). Three species-specific primer sets were designed according to the difference in mitochondrial genome of Gallus gallus domesticus, Anas platyrhynchos and Anser anse. The PCR conditions were optimized and the assay was well validated for high specificity and sensitivity (1 mg/µL). Especially, when artificial adulterants made from the mixture of three species were analyzed, the assay has still exhibited strong capability of differentiation. By using this developed method, two batches out of fourteen commercial GGEC products were identified to be adulterated by Anser anse. The newly proposed assay showed sufficient merits as a regular tool for the identification of counterfeits or adulterants of GGEC product for their pulverized and processed form, and even Chinese patent medicines composed of these species.

17.
Chin J Cancer ; 29(6): 591-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20507731

RESUMO

BACKGROUND AND OBJECTIVE: Research has shown that 5-bromotetrandrine (BrTet) can effectively reverse multidrug resistance (MDR). Imatinib plays an important role in cell proliferation. This study explored the efficacy of the combination of imatinib and BrTet on reversing MDR of tumor cells and its mechanism. METHODS: Cytoxicity was assessed by MTT assay. Apoptosis of K562/A02 cells was analyzed by flow cytometry. The expressions of mdr1 mRNA and P-glycoprotein (P-gp) were detected using reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. RESULTS: After 48 h of treatment with 0.0625 micromol/L imatinib, 0.5 micromol/L BrTet, or both, the 50% inhibition concentration (IC50) of daunorubicin (DNR) for the K562/A02 cells were 5.69 mg/L, 5.41 mg/L, and 2.19 mg/L, respectively. The gray-scale values of mdr1 mRNA expression in the K562/A02 cells were 0.65+/-0.02, 0.64+/-0.01, and 0.25+/-0.03, respectively. The expression levels of P-gp were 0.74+/-0.02, 0.52+/-0.02, and 0.29+/-0.02, respectively. All decreased significantly in the K562/A02 cells treated with both imatinib and BrTet compared to cells treated with imatinib and BrTet alone (P<0.05). The apoptosis rates of the K562/A02 cells increased without a significant difference after treatment with DNR, imatinib, or BrTet (P>0.05), while increased significantly after treatment with DNR combined with imatinib, BrTet, or both (P<0.05). CONCLUSIONS: The MDR of K562/A02 cells may be partially reversed by imatinib or BrTet, and the mechanism may be related to the downregulation of mdr1 mRNA and P-gp expression and the upregulation of the rate of apoptosis in K562/A02 cells. Imatinib combined with BrTet showed a synergistic effect on K562/A02 cells.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Benzilisoquinolinas/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Piperazinas/farmacologia , Pirimidinas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzamidas , Proliferação de Células/efeitos dos fármacos , Daunorrubicina/farmacocinética , Daunorrubicina/farmacologia , Regulação para Baixo , Sinergismo Farmacológico , Regulação Leucêmica da Expressão Gênica , Humanos , Mesilato de Imatinib , Células K562/efeitos dos fármacos , RNA Mensageiro/metabolismo
18.
Front Hum Neurosci ; 14: 7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32047426

RESUMO

Functional neuroimaging studies have emphasized distinct networks for social cognition and affective aspects of empathy. However, studies have not considered whether substrates of social cognition, such as the right temporoparietal junction (TPJ), play a role in affective responses to complex empathy-related stimuli. Here, we used repetitive transcranial magnetic stimulation (TMS) to test whether the right TPJ contributes to psychophysiological responses to another person's emotional suffering. We used a theory of mind functional localizer and image-guided TMS to target the sub-region of the right TPJ implicated in social cognition, and measured autonomic and subjective responses to an empathy induction video. We found evidence that TMS applied at 1 Hz over the right TPJ increased withdrawal of parasympathetic nervous system activity during the empathy induction (n = 32), but did not affect sympathetic nervous system activity (n = 27). Participants who received TMS over the right TPJ also reported feeling more irritation and annoyance, and were less likely to report feeling compassion over and above empathic sadness, than participants who received TMS over the vertex (N = 34). This study provides preliminary evidence for the role of right TPJ functioning in empathy-related psychophysiological and affective responding, potentially blurring the distinction between neural regions specific to social cognition vs. affective aspects of empathy.

19.
Plants (Basel) ; 9(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911695

RESUMO

Meehania montis-koyae Ohwi (Lamiaceae), which has been considered a narrow endemic and endangered species in Japan, was found in eastern China in 2011. China and Japan belong to the same floristic region and share many plant species, but it is very rare that Japanese narrow endemic species are newly found outside of the country. We examined herbarium specimens of both countries, and conducted analyses of molecular phylogenetics, population genetics, and divergence time estimation using two nuclear (ITS and ETS) gene regions and MIG-seq data. Chinese plants tend to become larger than Japanese, and they are different in leaf shape and floral features. Molecular phylogenetic analysis shows Chinese and Japanese M. montis-koyae are the closest relatives to each other. Population genetic analysis indicates no current gene flow between the Chinese and Japanese populations, and divergence time analysis shows they were separated during the late Miocene. We reach the conclusion that Chinese and Japanese M. montis-koyae have already become distinct biological entities, and a new taxon name Meehania zheminensis A. Takano, Pan Li, G.-H.Xia is proposed for the Chinese plants. A key to Asian Meehania species is provided.

20.
Enzyme Microb Technol ; 142: 109690, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33220869

RESUMO

Prosaikogenin D, a rare secondary saponin in Radix Bupleuri, has much higher in vivo bioactivities than its original glycoside saikosaponin B2. Its preparation methods, such as conventional acid hydrolysis and column chromatograph, are unfriendly to environment with serious pollution and undesired products. The aim of this study was to establish an efficient and clean approach for convenient preparation of this rare steroid saponin based on the enzymatic hydrolysis. Cellulase was selected from four commercial enzymes due to its higher hydrolysis performance. Then the hydrolysis conditions were optimized by response surface methodology after preliminary investigation on affecting factors by single-factor experiments. The reaction system was constructed by 100 µg/mL of saikosaponin B2 and 8.00 mg/mL of cellulase, which was incubated in HAc-NaAc buffer (pH 4.7) at 60 °C for 33 h. Consequently, a high conversion ratio of the substrate has been achieved at 95.04 %. The newly developed strategy is an efficient and clean approach for the preparation of prosaikogenin D and it is a promising technology in industrial application.


Assuntos
Ácido Oleanólico , Saponinas , Glicosídeos , Hidrólise , Ácido Oleanólico/análogos & derivados
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