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1.
Chromosoma ; 132(2): 89-103, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36939898

RESUMO

Although parthenogenesis is widespread in nature and known to have close relationships with bisexuality, the transitional mechanism is poorly understood. Artemia is an ideal model to address this issue because bisexuality and "contagious" obligate parthenogenesis independently exist in its congeneric members. In the present study, we first performed chromosome spreading and immunofluorescence to compare meiotic processes of Artemia adopting two distinct reproductive ways. The results showed that, unlike conventional meiosis in bisexual Artemia, meiosis II in parthenogenic Artemia is entirely absent and anaphase I is followed by a single mitosis-like equational division. Interspecific comparative transcriptomics showed that two central molecules in homologous recombination (HR), Dmc1 and Rad51, exhibited significantly higher expression in bisexual versus parthenogenetic Artemia. qRT-PCR indicated that the expression of both genes peaked at the early oogenesis and gradually decreased afterward. Knocking-down by RNAi of Dmc1 in unfertilized females of bisexual Artemia resulted in a severe deficiency of homologous chromosome pairing and produced univalents at the middle oogenesis stage, which was similar to that of parthenogenic Artemia, while in contrast, silencing Rad51 led to no significant chromosome morphological change. Our results indicated that Dmc1 is vital for HR in bisexual Artemia, and the deficiency of Dmc1 may be correlated with or even possibly one of core factors in the transition from bisexuality to parthenogenesis.


Assuntos
Artemia , Recombinases , Animais , Feminino , Recombinases/genética , Artemia/genética , Artemia/metabolismo , Bissexualidade , Meiose , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Partenogênese/genética , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo
2.
Biomacromolecules ; 25(7): 4604-4614, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38922332

RESUMO

As a natural renewable biomacromolecule, lignin has some inherently interesting properties such as fluorescence, antioxidation, and antibacterial performance. However, the unsatisfactory fluorescence and biological activities have greatly limited their value-added and large-scale applications. In this work, lignin nanoparticles (LNPs) grafted with vitamin B1 hybrid nanoparticles (LEVs) were obtained by using ethylenediamine and different contents of vitamin B1 through a simple hydrothermal method. The chemical structure, fluorescence properties, and bioactivity were characterized to assess the effects of ethylenediamine and vitamin B1 on the properties of LEVs. It was found that the fluorescence performance of synthesized LEV particles was improved with the increase in the amount of vitamin B1. The free radical scavenging rate (RSA, %) increased to 97.8%, while the antibacterial rates reached up to 99.9%. The antibacterial activity of LEV involved multiple combined mechanisms. The introduction of imine, amide groups, and positively charged VB1 of LEV will make it easier to interact with the negatively charged bacterial phospholipid membranes and cause bacterial lysis and death. Then, the PVA/LEV hydrogel composites were prepared by the freezing-thawing method, and the results showed that PVA/LEV hydrogels had more comprehensive performance such as improved mechanical properties and antioxidant and antibacterial activities, resulting in its great potential to be used as an efficient biomedical material.


Assuntos
Antibacterianos , Lignina , Antibacterianos/farmacologia , Antibacterianos/química , Lignina/química , Lignina/farmacologia , Nanopartículas/química , Tiamina/química , Tiamina/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Fluorescência , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia
3.
Biochem J ; 480(5): 385-401, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36852878

RESUMO

Doublesex (DSX) proteins are members of the Doublesex/mab-3-related (DMRT) protein family and play crucial roles in sex determination and differentiation among the animal kingdom. In the present study, we identified two Doublesex (Dsx)-like mRNA isoforms in the brine shrimp Artemia franciscana (Kellogg 1906), which are generated by the combination of alternative promoters, alternative splicing and alternative polyadenylation. The two transcripts exhibited sex-biased enrichment, which we termed AfrDsxM and AfrDsxF. They share a common region which encodes an identical N-terminal DNA-binding (DM) domain. RT-qPCR analyses showed that AfrDsxM is dominantly expressed in male Artemia while AfrDsxF is specifically expressed in females. Expression levels of both isoforms increased along with the developmental stages of their respective sexes. RNA interference with dsRNA showed that the knockdown of AfrDsxM in male larvae led to the appearance of female traits including an ovary-like structure in the original male reproductive system and an elevated expression of vitellogenin. However, silencing of AfrDsxF induced no clear phenotypic change in female Artemia. These results indicated that the male AfrDSXM may act as inhibiting regulator upon the default female developmental mode in Artemia. Furthermore, electrophoretic mobility shift assay analyses revealed that the unique DM domain of AfrDSXs can specifically bind to promoter segments of potential downstream target genes like AfrVtg. These data show that AfrDSXs play crucial roles in regulating sexual development in Artemia, and further provide insight into the evolution of sex determination/differentiation in sexual organisms.


Assuntos
Artemia , Isoformas de RNA , Animais , Masculino , Feminino , Artemia/genética , Isoformas de RNA/metabolismo , Processamento Alternativo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Diferenciação Sexual/genética
4.
Macromol Rapid Commun ; 44(6): e2200858, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36661258

RESUMO

Polymer melt strength (MS) is strongly correlated with its molecular structure, while their relationship is not very clear yet. In this work, designable long-chain branched polylactide (LCB-PLA) is prepared in situ by using a tailor-made (methyl methacrylate)-co-(glycidyl methacrylate) copolymer (MG) with accurate number of reactive sites. A new concept of branching density (φ) in the LCB-PLA system is defined to quantitively study their relationship. Importantly, a critical point of φc  = 5.5 mol/104  mol C is revealed for the first time, below which the zero-shear viscosity (η0 ) corresponding to MS increases slowly with a slope of Δη0 /Δφ = 1400, while it increases sharply above this critical point due to entanglement of neighboring LCB-PLA chains. Consequently, the MS of PLA increased by >100 times by optimizing the LCB structures while maintaining processibility. Therefore, this work provides a deeper understanding and feasible route in quantitative design of polymers with high(er) melt strength for some specialty applications.


Assuntos
Poliésteres , Polímeros , Poliésteres/química , Polímeros/química , Estrutura Molecular
5.
Entropy (Basel) ; 25(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37509946

RESUMO

The existence of the physiological tremor of the human hand significantly affects the application of tele-operation systems in performing high-precision tasks, such as tele-surgery, and currently, the process of effectively eliminating the physiological tremor has been an important yet challenging research topic in the tele-operation robot field. Some scholars propose using deep learning algorithms to solve this problem, but a large number of hyperparameters lead to a slow training speed. Later, the support-vector-machine-based methods have been applied to solve the problem, thereby effectively canceling tremors. However, these methods may lose the prediction accuracy, because learning energy cannot be accurately assigned. Therefore, in this paper, we propose a broad-learning-system-based tremor filter, which integrates a series of incremental learning algorithms to achieve fast remodeling and reach the desired performance. Note that the broad-learning-system-based filter has a fast learning rate while ensuring the accuracy due to its simple and novel network structure. Unlike other algorithms, it uses incremental learning algorithms to constantly update network parameters during training, and it stops learning when the error converges to zero. By focusing on the control performance of the slave robot, a sliding mode control approach has been used to improve the performance of closed-loop systems. In simulation experiments, the results demonstrated the feasibility of our proposed method.

6.
J Org Chem ; 87(9): 6064-6074, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35412840

RESUMO

The synthesis of isomerically pure olefins containing all-carbon quaternary centers is a challenging issue. Herein, we developed an efficient protocol for the synthesis of (Z)-olefins (27 examples, yield up to 97%, Z/E up to 99/1) and (E)-olefins (16 examples, yield up to 94%, E/Z up to 99/1) containing all-carbon quaternary centers. This protocol is adopted for the copper-catalyzed regioselective C-H alkenylation of the tertiary C(sp3)-H bond of 3-aryl benzofuran-2(3H)-ones with alkyne and alkenes. A diverse range of functional groups in the substrates is well-tolerated, such as F, Cl, Br, Me, OMe, ester, CF3, etc. A gram scale experiment was performed in good yield, and the radical mechanisms are also proposed based on the control experiments.

7.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501884

RESUMO

The demands for model accuracy and computing efficiency in fault warning scenarios are increasing as high-speed railway train technology continues to advance. The black box model is difficult to interpret, making it impossible for this technology to be widely adopted in the railway industry, which has strict safety regulations. This paper proposes a fault early warning machine learning model based on feature contribution and causal inference. First, the contributions of the features are calculated through the Shapley additive explanations model. Then, causal relationships are discovered through causal inference models. Finally, data from causal and high-contribution time series are applied to the model. Ablation tests are conducted with the Naïve Bayes, Gradient Boosting Decision Tree, eXtreme Gradient Boosting, and other models in order to confirm the efficiency of the method based on early warning data regarding the on-site high-speed train traction equipment circuit board failure. The findings indicate that the strategy improves the evaluation markers, including the early warning accuracy, precision, recall, and F1 score, by an average of more than 10%. There is a 35% improvement in the computing efficiency, and the model can provide feature causal graph verification for expert product decision-making.


Assuntos
Indústrias , Aprendizado de Máquina , Teorema de Bayes , Falha de Equipamento , Registros
8.
Chemistry ; 27(43): 11102-11109, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33876473

RESUMO

Metal-organic framework (MOF) is an ideal precursor/template for porous carbon, and its active components are uniformly doped, which can be used in energy storage and catalytic conversion fields. Metal-organic framework PCN-224 with carboxylporphyrin as the ligand was synthesized, and then Zn2+ and Co2+ ions were coordinated in the center of the porphyrin ring by post-modification. Here, PCN-224-ZnCo with different ratios of bimetallic Zn2+ /Co2+ ions were used as the precursor, and the metal-nitrogen-carbon(M-N-C) material of PCN-224-ZnCo-950 was obtained by pyrolyzing the precursor at 950 °C in Ar. Because Zn is easy to volatilize at 950 °C, the formed M-N-C materials can reflect different Co contents and different basic site concentrations. The formed material still maintains the original basic framework. With the increase of Zn2+ /Co2+ ratio in precursor, the concentration of N-containing alkaline sites in pyrolysis products gradually increase. Compared with the precursor, PCN-224-ZnCo1 -950 with Zn2+ /Co2+ =1 : 1 has greatly improved basicity and suitable acidic/ alkaline site concentration. It can be efficiently used to carbon dioxide absorption and catalyze the cycloaddition of CO2 with epoxide. More importantly, the current method of adjusting the acidic/basic sites in M-N-C materials through volatilization of volatile metals can provide an effective strategy for adjusting the catalysis of MOF derivatives with porphyrin structure.

9.
Biomacromolecules ; 22(6): 2693-2701, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34077181

RESUMO

In recent years, lignin specific activities, such as antioxidation and antibacterial and anti-ultraviolet performance, have drawn more and more attention. Nevertheless, the insufficient radical scavenging (antioxidation) activity has become one of the main drawbacks that limits its high-value application. In this study, lignin nanoparticles (LNPs) were prepared via a facile acid treatment strategy. Subsequently, surface amination of LNPs (a-LNPs) was carried out through the Mannich reaction. Specifically, the antioxidant behavior of LNPs and modified LNPs was evaluated by DPPH/DMPO radical scavenging and in vitro HeLa cell reactive oxygen species (ROS) scavenging tests, which demonstrated that the antioxidation activity of a-LNPs was more evident than that of both LNPs and butylated hydroxytoluene (BHT) commercial antioxidant. The mechanism of the radical scavenging ability of aminated LNPs was elucidated and proved to be related to the bond dissociation enthalpy of Ar-O···H, determined by the electron-donating effect of the substituted groups in the ortho-position. Meanwhile, the morphologies, solubilities, and UV-absorbing and antibacterial behavior of LNPs and a-LNPs were also studied, and the results showed that a-LNP sample exhibited higher UV resistance performance than LNPs. We expected that the modified LNPs with high antioxidation activity can serve as a safe and lower-cost biobased antioxidant.


Assuntos
Antioxidantes , Nanopartículas , Aminação , Células HeLa , Humanos , Lignina
10.
Phys Chem Chem Phys ; 23(33): 18125-18136, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34397065

RESUMO

Photocatalytic water splitting is a promising technology to solve serious energy and environmental problems. The PtS2 monolayer has been previously predicted to be a water splitting photocatalyst. But the high efficiency of carrier recombination in the monolayer results in poor photocatalytic performance. It is well known that the construction of van der Waals (vdW) heterojunctions can improve the photocatalytic performance of a monolayer. In this investigation, we constructed a PtS2/SnS2 vdW heterojunction and systematically investigated the influence of the doping position and doping ratio on its performance using density functional theory calculations. Interestingly, the band alignment transforms from Type-II to Type-I and from Type-I to Type-II when the S in SnS2 is replaced with Se in the PtS2/SnS2 vdW heterojunction and the S in PtS2 is replaced with Se in the PtS2/SnSe2 vdW heterojunction, respectively. More importantly, from the PtS2/SnS2 to PtSe2/SnSe2 vdW heterojunction, the decomposition of water also changes from semi-decomposed water to fully decomposed water. Furthermore, the results show that the direct Z-scheme photocatalytic mechanism exists in the PtSSe/SnSe2 vdW heterojunction by analysis of the migration paths of photoinduced electrons and holes. And compared with the PtS2/SnS2, the PtSSe/SnSe2 heterostructure exhibits better photocatalytic water splitting activities. These results can provide a direction that doping can improve the photocatalytic water splitting performance of heterojunction photocatalysts.

11.
J Biol Chem ; 294(16): 6598-6611, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30765604

RESUMO

Cellular quiescence, a reversible state in which growth, proliferation, and other cellular activities are arrested, is important for self-renewal, differentiation, development, regeneration, and stress resistance. However, the physiological mechanisms underlying cellular quiescence remain largely unknown. In the present study, we used embryos of the crustacean Artemia in the diapause stage, in which these embryos remain quiescent for prolonged periods, as a model to explore the relationship between cell-membrane potential (Vmem) and quiescence. We found that Vmem is hyperpolarized and that the intracellular chloride concentration is high in diapause embryos, whereas Vmem is depolarized and intracellular chloride concentration is reduced in postdiapause embryos and during further embryonic development. We identified and characterized the chloride ion channel protein cystic fibrosis transmembrane conductance regulator (CFTR) of Artemia (Ar-CFTR) and found that its expression is silenced in quiescent cells of Artemia diapause embryos but remains constant in all other embryonic stages. Ar-CFTR knockdown and GlyH-101-mediated chemical inhibition of Ar-CFTR produced diapause embryos having a high Vmem and intracellular chloride concentration, whereas control Artemia embryos released free-swimming nauplius larvae. Transcriptome analysis of embryos at different developmental stages revealed that proliferation, differentiation, and metabolism are suppressed in diapause embryos and restored in postdiapause embryos. Combined with RNA sequencing (RNA-Seq) of GlyH-101-treated MCF-7 breast cancer cells, these analyses revealed that CFTR inhibition down-regulates the Wnt and Aurora Kinase A (AURKA) signaling pathways and up-regulates the p53 signaling pathway. Our findings provide insight into CFTR-mediated regulation of cellular quiescence and Vmem in the Artemia model.


Assuntos
Artemia/embriologia , Membrana Celular/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Diapausa/fisiologia , Embrião não Mamífero/embriologia , Animais , Artemia/genética , Proteínas de Artrópodes/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Humanos , Células MCF-7
12.
Hum Mol Genet ; 27(21): 3787-3800, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010909

RESUMO

Primary ovarian insufficiency (POI) leads to infertility and premature menopause in young women. The genetic etiology of this disorder remains unknown in most patients. Using whole exome sequencing of a large Chinese POI pedigree, we identified a heterozygous 5 bp deletion inducing a frameshift in BNC1, which is predicted to result in a non-sense-mediated decay or a truncated BNC1 protein. Sanger sequencing identified another BNC1 missense mutation in 4 of 82 idiopathic patients with POI, and the mutation was absent in 332 healthy controls. Transfection of recombinant plasmids with the frameshift mutant and separately with the missense mutant in HEK293T cells led to abnormal nuclear localization. Knockdown of BNC1 was found to reduce BMP15 and p-AKT levels and to inhibit meiosis in oocytes. A female mouse model of the human Bnc1 frameshift mutation exhibited infertility, significantly increased serum follicle-stimulating hormone, decreased ovary size and reduced follicle numbers, consistent with POI. We report haploinsufficiency of BNC1 as an etiology of human autosomal dominant POI.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mutação de Sentido Incorreto , Insuficiência Ovariana Primária/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Adulto , Idoso , Animais , Povo Asiático/genética , Análise Mutacional de DNA , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Linhagem , Insuficiência Ovariana Primária/metabolismo , Sequenciamento do Exoma , Adulto Jovem
13.
Biochem J ; 476(12): 1753-1769, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31189566

RESUMO

To cope with harsh environments, the Artemia shrimp produces gastrula embryos in diapause, a state of obligate dormancy, having cellular quiescence and suppressed metabolism. The mechanism behind these cellular events remains largely unknown. Here, we study the regulation of cell quiescence using diapause embryos of Artemia We found that Artemia DEK (Ar-DEK), a nuclear factor protein, was down-regulated in the quiescent cells of diapause embryos and enriched in the activated cells of post-diapause embryos. Knockdown of Ar-DEK induced the production of diapause embryos whereas the control Artemia released free-swimming nuaplii. Our results indicate that Ar-DEK correlated with the termination of cellular quiescence via the increase in euchromatin and decrease in heterochromatin. The phenomena of quiescence have many implications beyond shrimp ecology. In cancer cells, for example, knockdown of DEK also induced a short period of cellular quiescence and increased resistance to environmental stress in MCF-7 and MKN45 cancer cell lines. Analysis of RNA sequences in Artemia and in MCF-7 revealed that the Wnt and AURKA signaling pathways were all down-regulated and the p53 signaling pathway was up-regulated upon inhibition of DEK expression. Our results provide insight into the functions of Ar-DEK in the activation of cellular quiescence during diapause formation in Artemia.


Assuntos
Artemia/embriologia , Proteínas de Artrópodes/biossíntese , Diapausa/fisiologia , Embrião não Mamífero/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Receptores da Família Eph/biossíntese , Via de Sinalização Wnt/fisiologia , Animais , Artemia/genética , Proteínas de Artrópodes/genética , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Humanos , Células MCF-7 , Receptores da Família Eph/genética
14.
Fish Shellfish Immunol ; 92: 1-10, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31141718

RESUMO

Rimicaris exoculata (Decapoda: Bresiliidae) is one of the dominant species of hydrothermal vent communities, which inside its gill chamber harbors ectosymbioses with taxonomic invariability while compositional flexibility. Several studies have revealed that the establishment of symbiosis can be initiated and selected by innate immunity-related pattern recognition receptors (PRRs), such as C-type lectins (CTLs). In this research, a CTL was identified in R. exoculata (termed RCTL), which showed high expression at both mRNA and protein levels in the scaphognathite, an organ where the ectosymbionts are attached outside its setae. Linear correlationships were observed between the relative quantities of two major symbionts and the expression of RCTL based on analyzing different shrimp individuals. The recombinant protein of RCTL could recognize and agglutinate the cultivable γ-proteobacterium of Escherichia coli in a Ca2+-dependent manner, obeying a dose-dependent and time-cumulative pattern. Unlike conventional crustacean CTLs, the involvement of RCTL could not affect the bacterial growth, which is a key issue for the successful establishment of symbiosis. These results implied that RCTL might play a critical role in symbiotic recognition and attachment to R. exoculata. It also provides insights to understand how R. exoculata adapted to such a chemosynthesis-based environment.


Assuntos
Decápodes/genética , Decápodes/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Escherichia coli/fisiologia , Perfilação da Expressão Gênica , Lectinas Tipo C/química , Filogenia , Alinhamento de Sequência , Simbiose
15.
Biometals ; 32(2): 251-264, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30756217

RESUMO

Rimicaris exoculata (Decapoda: Bresiliidae) is one of the dominant species among hydrothermal vent communities along the Mid-Atlantic Ridge. This shrimp can tolerate high concentrations of heavy metals such as iron, but the mechanisms used for detoxification and utilization of excess metals remain largely unknown. Ferritin is a major iron storage protein in most living organisms. The central heavy subunit of ferritin (H-ferritin) possesses ferroxidase activity and converts iron from Fe2+ to Fe3+, the non-toxic form used for storage. In the present study, the H-ferritin RexFrtH was identified in the hydrothermal vent shrimp R. exoculata, and found to be highly expressed in the gill, the main organ involved in bioaccumulation of metals, at both RNA and protein levels. Accumulation of RexFrtH decreased from efferent to afferent vessels, coinciding with the direction of water flow through the gills. Fe3+ was localized with RexFrtH, and in vitro iron-binding and ferroxidase assays using recombinant RexFrtH confirmed the high affinity for iron. Based on these results, we propose a model of iron metabolism in R. exoculata gills; ferrous iron from ambient hydrothermal water accumulates and is converted and stored in ferric form by RexFrtH as an iron reservoir when needed for metabolism, or excreted as an intermediate to prevent iron overload. The findings expand our understanding of the adaptation strategies used by shrimps inhabiting extreme hydrothermal vents to cope with extremely high heavy metal concentrations.


Assuntos
Apoferritinas/metabolismo , Decápodes/metabolismo , Fontes Hidrotermais , Ferro/metabolismo , Animais
16.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3178-3186, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31602870

RESUMO

Ziziphora bungeana is a kind of medicinal plants belongs to Labiatae,and it also a kind of geoherbs in Xinjiang. The main active ingredient linarin has a higher content in inflorescence than in other parts. In this study,high-throughput sequencing technology was used to reveal the transcriptome of the inflorescence of Z. bungeana,77 366 unigenes were acquired,of which 56 375 unigenes were annotated based on search of the database and classification. Through the analysis of metabolic pathways,sixty unigenes were probably encoding some enzymes involved in the flavonoid biosynthesis pathways. The contents of linarin in different parts were determined and the key genes were verified by qRT-PCR. The discovery provides the research basis for further analysis of the enzyme genes involved in the biosynthesis of the major flavonoid components in Z. bungeana.


Assuntos
Flavonoides/biossíntese , Lamiaceae/química , Transcriptoma , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala
17.
Zhongguo Zhong Yao Za Zhi ; 43(9): 1769-1773, 2018 May.
Artigo em Zh | MEDLINE | ID: mdl-29902884

RESUMO

This study aimed to develop an HPLC method for simultaneous determination of the 3 components in Ziziphora bungeana. The optimum HPLC condition was as follows:ZORBAX SB-C18 column(4.6 mm×250 mm, 5.0 µm)with gradient elution of methanol (A)-0.2% glacial acetic acid (B), detection wavelength 340 nm,column temperature 30 °C, flow rate 1 mL·min⁻¹. There were good linearity between peak areas and injection quantity of caffeic acid, rosmarinic acid, and linarin in the range of 2-40 mg·L⁻¹ï¼ˆr=0.999 9), 3-60 mg·L⁻¹ï¼ˆr=1), 7-140 mg·L⁻¹ï¼ˆr=0.999 9), respectively. The average recoveries were 100.9%(RSD 1.3%),98.25%(RSD 2.0%),and 98.73%(RSD 1.5%), respectively. The HPLC method was stable and accurate, which could be used to detect caffeic acid,rosmarinic acid, and linarin in Ziziphora bungeana.


Assuntos
Medicamentos de Ervas Chinesas , Lamiaceae , Cromatografia Líquida de Alta Pressão
18.
Zhongguo Zhong Yao Za Zhi ; 43(9): 1737-1748, 2018 May.
Artigo em Zh | MEDLINE | ID: mdl-29902879

RESUMO

With the development and change of Uygur medicine, The sources,medicinal parts and producing area of some Uygur Medicine have changed. It is more important to master the classification, distribution and change of Uygur medicinal materials. These were more than 1 200 kinds Uygur medicine in history were resaerched by field investigation, philological research, and textual research, which main source of original plant were 140 families, 510 genera, 840 species; and source of original animal were 76 families, 107 genera, the original animal 141 species; 55 kinds of original mineral, which main producer were Xinjiang and Central Asia, West Asia, the Mediterranean, and North Africa, Southeast Asia and other provinces in China, there are individual medicinal materials from the Americas, Europe and other places. Through this study the classification, distribution, source and evolution of specific families and genera of Uygur medicine resources have mastered.It is hoped to provide theoretical basis for further research and development of Uygur medicinal materials.


Assuntos
Plantas Medicinais , China , Europa (Continente)
19.
J Biol Chem ; 291(9): 4462-72, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26733200

RESUMO

Autophagy is an evolutionarily conserved degradative process that allows cells to maintain homoeostasis in numerous physiological situations. This process also functions as an essential protective response to endoplasmic reticulum (ER) stress, which promotes the removal and degradation of unfolded proteins. However, little is known regarding the mechanism by which autophagy is initiated and regulated in response to ER stress. In this study, different types of autophagy were identified in human gastric cancer MKN45 cells in response to the stress induced by nutrient starvation or lipotoxicity in which the regulation of these pathways is mammalian target of rapamycin (mTOR)-dependent or -independent, respectively. Interestingly, we found that p8, a stress-inducible transcription factor, was enhanced in MKN45 cells treated with palmitic acid to induce lipotoxicity. Furthermore, an increase in autophagy was observed in MKN45 cells stably overexpressing p8 using a lentivirus system, and autophagy induced by palmitic acid was blocked by p8 RNAi compared with the control. Western blotting analyses showed that autophagy was regulated by p8 or mTOR in response to the protein kinase-like endoplasmic reticulum kinase/activating transcription factor 6-mediated ER stress of lipotoxicity or the parkin-mediated mitochondrial stress of nutrient starvation, respectively. Furthermore, our results indicated that autophagy induced by palmitic acid is mTOR-independent, but this autophagy pathway was regulated by p8 via p53- and PKCα-mediated signaling in MKN45 cells. Our findings provide insights into the role of p8 in regulating autophagy induced by the lipotoxic effects of excess fat accumulation in cells.


Assuntos
Autofagia , Proteínas de Ligação a DNA/metabolismo , Estresse do Retículo Endoplasmático , Ácidos Graxos não Esterificados/efeitos adversos , Transdução de Sinais , Fatores de Transcrição/metabolismo , Regulação para Cima , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Microscopia de Fluorescência , Ácido Palmítico/efeitos adversos , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Regulação para Cima/efeitos dos fármacos
20.
BMC Biol ; 14: 16, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26941127

RESUMO

BACKGROUND: In eukaryotes, tRNA trafficking between the nucleus and cytoplasm is a complex process connected with cell cycle regulation. Such trafficking is therefore of fundamental importance in cell biology, and disruption of this process has grave consequences for cell viability and survival. To cope with harsh habitats, Artemia has evolved a special reproductive mode to release encysted embryos in which cell division can be maintained in a dormancy state for a long period. RESULTS: Using Artemia as a peculiar model of the cell cycle, an La-related protein from Artemia, named Ar-Larp, was found to bind to tRNA and accumulate in the nucleus, leading to cell cycle arrest and controlling the onset of diapause formation in Artemia. Furthermore, exogenous gene expression of Ar-Larp could induce cell cycle arrest in cancer cells and suppress tumor growth in a xenograft mouse model, similar to the results obtained in diapause embryos of Artemia. Our study of tRNA trafficking indicated that Ar-Larp controls cell cycle arrest by binding to tRNAs and influencing their retrograde movement from the cytoplasm to the nucleus, which is connected to pathways involved in cell cycle checkpoints. CONCLUSIONS: These findings in Artemia offer new insights into the mechanism underlying cell cycle arrest regulation, as well as providing a potentially novel approach to study tRNA retrograde movement from the cytoplasm to the nucleus.


Assuntos
Artemia/citologia , Proteínas de Artrópodes/metabolismo , Ciclo Celular , RNA de Transferência/metabolismo , Animais , Pontos de Checagem do Ciclo Celular , Linhagem Celular , Núcleo Celular/metabolismo , Feminino , Humanos , Camundongos Endogâmicos BALB C , Transporte de RNA
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