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1.
Artigo em Inglês | MEDLINE | ID: mdl-30844694

RESUMO

Thiamin, riboflavin and pyridoxal phosphate (PLP) concentrations are useful indices for evaluating vitamin B1, B2 and B6 status. Several HPLC assays have been developed for determining thiamin, riboflavin and PLP in biological matrix. However, no existing LC-MS/MS methods can be used to quantify thiamin, riboflavin and PLP in dried blood spots (DBSs), which are often used as a sampling/storage vessel for blood from infants and children. This study evaluated the validity, reliability and stability of an LC-MS/MS assay for measuring thiamin, riboflavin and PLP in DBS cards. DBS samples were deproteinized by adding trichloroacetic acid containing thiamine-[13C4], riboflavin-[13C4,15N2] and pyridoxal-d3 as internal standards. Thiamin, riboflavin and PLP were separated on a C8 column with a 5-min run time. Both the between-run and within-run variable coefficients (CV% values) were < 8.56%. The accuracies were good and showed relative errors (RE% values) from -7.40% to 3.12%. The lower limits of quantification (LLOQs) ranged from 0.2 to 0.5 ng/mL, and the recoveries were from 81.49% to 112.23% for all 3 analytes. The matrix effects (ME% values) were acceptable, and the CV% values of the internal standard-normalized matrix factors were <15% (n = 6). Thiamin, riboflavin and PLP were stable on the DBS card during at least 15 days of room-temperature storage under vacuum in the dark, and the measurements of thiamin, riboflavin and PLP in the DBSs showed good agreement with the corresponding concentrations determined from liquid blood (R2 values >0.96). The validated method was successfully applied to the nutritional assessment of vitamins B1, B2, and B6 in 48 Chinese children.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Teste em Amostras de Sangue Seco/métodos , Riboflavina/sangue , Espectrometria de Massas em Tandem/métodos , Tiamina/sangue , Vitamina B 6/sangue , Pré-Escolar , Humanos , Lactente , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
2.
Dev Comp Immunol ; 91: 101-107, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30385317

RESUMO

Caspase, an aspartate specific proteinase mediating apoptosis, plays a key role in immune response. In our previous study, the expression of a caspase gene was up-regulated in a transcriptome library from the haematopoietic tissue (Hpt) cells of red claw crayfish Cherax quadricarinatus post white spot syndrome virus (WSSV) infection. To further reveal the effect of caspase on WSSV infection, we cloned this caspase gene (denominated as CqCaspase) with an open reading frame of 1062 bp, which encoded 353 amino acids with a caspase domain (CASc) containing a p20 subunit and a p10 subunit. Tissue distribution analysis indicated that the mRNA transcript of CqCaspase was widely expressed in all tested tissues with the highest expression in Hpt, while the lowest expression in muscle. To further explore the effect of CqCaspase on WSSV replication, recombinant protein of CqCaspase (rCqCaspase) was delivered into Hpt cells followed by WSSV infection, which resulted in a significantly decreased expression of both an immediate early gene IE1 and a late envelope protein gene VP28 of WSSV, suggesting that CqCaspase, possibly by the enhanced apoptotic activity, had a strong negative effect on the WSSV replication. These data together indicated that CqCaspase was likely to play a vital role in immune defense against WSSV infection in a crustacean C. quadricarinatus, which shed a new light on the mechanism study of WSSV infection in crustaceans.


Assuntos
Proteínas de Artrópodes/genética , Astacoidea/imunologia , Caspases/genética , Infecções por Vírus de DNA/imunologia , Hemócitos/fisiologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/metabolismo , Astacoidea/virologia , Caspases/metabolismo , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação Viral da Expressão Gênica , Imunidade Inata/genética , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Replicação Viral
3.
Dev Comp Immunol ; 84: 264-272, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29510164

RESUMO

Influenza A virus non-structural-1A binding protein (named as Ns1abp) was originally identified as a host protein from human that bound to the viral NS-1 protein. In our previous study, the expression of an Ns1abp-like gene (denoted as CqNs1abp-like gene) was found to be up-regulated in a transcriptome library from the haematopoietic tissue (Hpt) cells of red claw crayfish Cherax quadricarinatus post white spot syndrome virus (WSSV) infection. To elucidate the role of CqNs1abp-like gene involved in WSSV infection, we cloned the CqNs1abp-like gene in which the open reading frame was 2232 bp, encoding 743 amino acids with two typical domains of one BTB (Broad-Complex, Tramtrack and Bric a brac) domain at N-terminal and six Kelch domains at C-terminal. The gene expression profile showed that the mRNA transcript of CqNs1abp-like gene was widely expressed in all the tested tissues with highest expression in nerve, relatively high expression in Hpt and lowest expression in eyestalk. Importantly, both the WSSV entry and the viral replication were significantly reduced in Hpt cells after gene silencing of CqNs1abp-like gene. By using protein pull-down assay, we found that the recombinant BTB domain, six Kelch domains and CqNs1abp-like intact protein were all bound to the WSSV envelope protein VP28, respectively, in which the BTB domain showed slightly less binding affinity than that of the six Kelch domains or the recombinant intact protein. Besides, the WSSV entry into Hpt cells was clearly decreased when the virus was pre-incubated with the recombinant BTB domain, six Kelch domains, or the recombinant CqNs1abp-like intact protein, respectively, suggesting that the CqNs1abp-like gene was likely to function as a putative recognition molecular towards WSSV infection in a crustacean C. quadricarinatus. Taken together, these data shed new light on the mechanism of WSSV infection and a putatively novel target on anti-WSSV infection in crustacean farming.


Assuntos
Proteínas de Artrópodes/genética , Astacoidea/imunologia , Infecções por Vírus de DNA/imunologia , Hemócitos/fisiologia , Tecido Nervoso/fisiologia , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/metabolismo , Células Cultivadas , Clonagem Molecular , Humanos , Vírus da Influenza A/fisiologia , Proteínas Nucleares/metabolismo , Domínios Proteicos/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Proteínas do Envelope Viral/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
4.
Dev Comp Immunol ; 84: 109-116, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29428488

RESUMO

The ß-thymosins are a group of structurally related, highly conserved intracellular small peptides in vertebrates with various biological functions, including cytoskeletal remodeling, neuronal development, cell migration, cell survival, tissue repair and inhibition of inflammation. In contrast to vertebrates, the function of ß-thymosin is not fully understood in crustaceans. Previously, we found that a thymosin-repeated protein1 (CqTRP1) gene was up-regulated after white spot syndrome virus (WSSV) challenge in hematopoietic tissue (Hpt) cells from the red claw crayfish Cherax quadricarinatus. To further identify the effect of CqTRP1 on WSSV infection, a full length cDNA sequence of ß-thymosin homologue was cloned and analyzed from red claw crayfish followed by functional study. The CqTRP1 cDNA contains an open reading frame of 387 nucleotides encoding a protein of 129 amino acids with a putative molecular mass of 14.3 kDa. The amino acid sequence showed high identity with other ß-thymosins and contained three characteristic thymosin ß actin-binding motifs, suggesting that CqTRP1 was a member of the ß-thymosin family. Tissue distribution analysis revealed a ubiquitous presence of CqTRP1 in all the examined tissues with the highest expression in hemocytes, Hpt and gonad at the transcriptional level. Interestingly, the gene silencing of endogenous CqTRP1 by RNAi enhanced the WSSV replication in Hpt cells. Meanwhile, the WSSV replication was significantly reduced in the Hpt cell cultures if overloaded with a recombinant CqTRP1. Taken together, these data clearly indicated that CqTRP1 was likely to be associated with the anti-WSSV response in a crustacean C. quadricarinatus, which provides new strategy against white spot disease in crustacean aquaculture.


Assuntos
Proteínas de Artrópodes/genética , Astacoidea/imunologia , Infecções por Vírus de DNA/imunologia , Gônadas/metabolismo , Hemócitos/metabolismo , Timosina/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Aquicultura , Proteínas de Artrópodes/metabolismo , Astacoidea/virologia , Clonagem Molecular , Gônadas/imunologia , Gônadas/virologia , Hemócitos/imunologia , Hemócitos/virologia , Proteínas dos Microfilamentos/genética , RNA Interferente Pequeno/genética , Frutos do Mar , Timosina/metabolismo , Replicação Viral
5.
Dev Comp Immunol ; 82: 104-112, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29341872

RESUMO

It is well known that iron is an essential element for all living organism. The intracellular iron availability is also important for the host's innate immune response to various pathogens, in which the iron homeostasis can be regulated by ferritin due to its iron storage property. In this study, a full-length cDNA sequence of ferritin (named as CqFerritin) was identified with 1410 bp from red claw crayfish Cherax quadricarinatus, which contained an open reading frame of 513 bp, encoding 170 amino acids with a conserved ferritin domain. Tissue distribution analysis demonstrated that CqFerritin was widely expressed in various tissues with high presence in haemocyte, haematopoietic tissue (Hpt) and heart, while lowest expression in hepatopancreas. In addition, loss-of-function of CqFerritin by gene silencing resulted in significantly higher expression of an envelope protein VP28 of white spot syndrome virus (WSSV) in red claw crayfish Hpt cell cultures, indicating the potential antiviral response of CqFerritin. To further explore the effect on WSSV replication by CqFerritin, recombinant CqFerritin protein (rCqFerritin) was transfected into Hpt cells followed by WSSV infection. Importantly, the replication of WSSV was obviously decreased in Hpt cells if transfected with rCqFerritin protein, suggesting that CqFerritin had clearly negative effect on WSSV infection. Furthermore, intracellular accumulation of iron ions was found to promote the WSSV replication in a dose-dependent manner, illustrating that the iron level regulated by CqFerritin was likely to be vital for WSSV infection in red claw crayfish. Taken together, these data suggest that CqFerritin plays an important role in immune defense against WSSV infection in a crustacean C. quadricarinatus.


Assuntos
Proteínas de Artrópodes/metabolismo , Astacoidea/imunologia , Infecções por Vírus de DNA/imunologia , Ferritinas/metabolismo , Sistema Hematopoético/metabolismo , Ferro/metabolismo , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/genética , Astacoidea/virologia , Células Cultivadas , Clonagem Molecular , DNA Complementar/genética , Ferritinas/genética , Imunidade Inata , Transporte de Íons , Miocárdio/metabolismo , Replicação Viral
6.
Dev Comp Immunol ; 81: 342-347, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29288063

RESUMO

The gradual increase of CO2 concentration in the atmosphere, absorbed by the ocean surface water through air to sea equilibration termed ocean acidification (OA), leads to the decline of pH in seawater. It is not clear so far how the composition of fatty acids, particular the immune-related, in marine crustacean and the subsequent energy supply in marine ecosystem are affected by OA. The brine shrimp Artemia sinica is an open and common feed that provide essential fatty acids for mariculture. In this study, the fatty acids profiles of brine shrimp cultured under different lower pH levels of CO2 driven seawater were investigated. The results showed a significant reduction of the proportion of total saturated fatty acids under the pH7.6 within one week. Meanwhile, the percentage of total monounsaturated fatty acids was significantly decreased at day 14 under pH7.8, and this percentage gave a significant increase of proportion within one week under pH7.6. Furthermore, the relative content of total polyunsaturated fatty acids (PUFAs) was found to be clearly increased with exposure to different seawater acidification at day 1, suggesting that the brine shrimp immune response was likely to be affected by acidified seawater as the PUFAs have been well known to be involved in immunomodulatory effects through alterations on cell membrane fluidity/lipid mediators and gene expression of cell signaling pathways. Notably, eicosapentaenoic acid and docosahexaenoic acid, which have essential effect on various physiological processes such as inflammatory cytokines production and cell structural stability, were strongly increased under two lower pH treatments within one week and with the significant increase at day 1 under pH7.6. These data clearly supported the hypothesis that OA might affect fatty acids composition, likely also the innate immunity, in crustacean and the subsequent energy transfer by food-chain system in the marine ecosystem.


Assuntos
Artemia/fisiologia , Dióxido de Carbono/química , Membrana Celular/metabolismo , Ácidos Graxos/química , Imunidade Inata , Água do Mar/química , Animais , Membrana Celular/química , Ácidos Docosa-Hexaenoicos/química , Ácidos Docosa-Hexaenoicos/metabolismo , Ecossistema , Ácido Eicosapentaenoico/química , Ácido Eicosapentaenoico/metabolismo , Metabolismo Energético , Ácidos Graxos/metabolismo , Cadeia Alimentar , Concentração de Íons de Hidrogênio , Imunomodulação , Inflamação , Biologia Marinha , Oceanos e Mares , Transdução de Sinais
7.
Dev Comp Immunol ; 79: 186-194, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29102705

RESUMO

White spot syndrome virus (WSSV) is a lethal pathogen of shrimp and many other crustaceans, which has been causing huge economic losses in global aquaculture. Laminin receptor (LR) is a cell surface receptor which participates in the interactions between cells as well as cells and extracellular matrix. Previously, we found that a CqLR-like gene was responsive to WSSV infection in the hematopoietic tissue (Hpt) cells from red claw crayfish Cherax quadricarinatus. To further reveal the role of CqLR-like gene involved in WSSV infection, the full-length cDNA of CqLR-like gene was cloned with 1000 bp, and the open reading frame encoded 308 amino acids with a conserved laminin-binding domain. Importantly, both the WSSV entry and viral replication were strongly reduced in Hpt cells after loss-of-function of CqLR-like gene by gene silencing. Protein interaction assay demonstrated that the recombinant CqLR-like protein could bind to WSSV virion in vitro by enzyme-linked immunosorbent assay and the binding affinity was in a dose-dependent manner. Furthermore, recombinant CqLR-like protein was found to bind to WSSV envelop protein VP28, but not other envelop proteins tested including VP19, VP24, and VP26, by pull down assay in HEK293T cells. In regarding to that LR is mainly localized on many types of cells' membrane, these data together suggested that CqLR-like protein was likely to function as a putative recognition molecule towards WSSV and act in the viral entry into a crustacean host cell, which may benefit the elucidation of the WSSV pathogenesis and further the pharmaceutical target for the possibly effective control of WSSV disease.


Assuntos
Astacoidea/imunologia , Infecções por Vírus de DNA/imunologia , Receptores de Laminina/genética , Proteínas do Envelope Viral/metabolismo , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Clonagem Molecular , Células HEK293 , Humanos , Terapia de Alvo Molecular , Ligação Proteica , RNA Interferente Pequeno/genética , Internalização do Vírus , Replicação Viral
8.
Fish Shellfish Immunol ; 59: 469-483, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27825947

RESUMO

White spot syndrome virus (WSSV) is one of the most prevalent and widespread viruses in both shrimp and crayfish aquaculture. MicroRNAs (miRNAs) are crucial post-transcriptional regulators and play critical roles in cell differentiation and proliferation, apoptosis, signal transduction and immunity. In this study, miRNA expression profiles were identified via deep sequencing in red claw crayfish Cherax quadricarinatus haematopoietic tissue (Hpt) cell cultures infected with WSSV at both early (i.e., 1 hpi) and late (i.e., 12 hpi) infection stages. The results showed that 2 known miRNAs, namely, miR-7 and miR-184 play key roles in immunity. Meanwhile, 106 novel miRNA candidates were predicted by software in these combined miRNA transcriptomes. Compared with two control groups, 36 miRNAs showed significantly different expression levels after WSSV challenge. Furthermore, 10 differentially expressed miRNAs in WSSV-exposed Hpt cells were randomly selected for expression analysis by quantitative real-time RT-PCR. Consistent with the expression profiles identified by deep sequencing, RT-PCR showed a significant increase or decrease in miRNA expression in Hpt cells after WSSV infection. Prediction of targets of miRNAs such as miR-7, cqu-miR-52, cqu-miR-126 and cqu-miR-141 revealed that their target genes have diverse biological roles, including not only immunity but also transcriptional regulation, energy metabolism, cell communication, cell differentiation, cell death, autophagy, endocytosis and apoptosis. These results provide insight into the molecular mechanism of WSSV infection and highlight the function of miRNAs in the regulation of the immune response against WSSV infection in crustaceans.


Assuntos
Astacoidea/genética , Astacoidea/virologia , Imunidade Inata , MicroRNAs/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Astacoidea/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
9.
Fish Shellfish Immunol ; 58: 669-677, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27725259

RESUMO

Gradually increasing atmospheric CO2 partial pressure (pCO2) has caused an imbalance in carbonate chemistry and resulted in decreased seawater pH in marine ecosystems, termed seawater acidification. Anthropogenic seawater acidification is postulated to affect the physiology of many marine calcifying organisms. To understand the possible effects of seawater acidification on the proteomic responses of a marine crustacean brine shrimp (Artemia sinica) three groups of cysts were hatched and further raised in seawater at different pH levels (8.2 as control and 7.8 and 7.6 as acidification stress levels according to the predicted levels at the end of this century and next century, respectively) for 1, 7 and 14 days followed by examination of the protein expression changes via two-dimensional gel electrophoresis. Searches of protein databases revealed that 67 differential protein spots were altered due to lower pH level (7.6 and 7.8) stress in comparison to control groups (pH 8.2) by mass spectrometry. Generally, these differentially expressed proteins included the following: 1) metabolic process-related proteins involved in glycolysis and glucogenesis, nucleotide/amino acid/fatty acid metabolism, protein biosynthesis, DNA replication and apoptosis; 2) stress response-related proteins, such as peroxiredoxin, thioredoxin peroxidase, 70-kDa heat shock protein, Na/K ATPase, and ubiquinol-cytochrome c reductase; 3) immune defence-related proteins, such as prophenoloxidase and ferritin; 4) cytoskeletal-related proteins, such as myosin light chain, TCP1 subunit 2, tropomyosin and tubulin alpha chain; and 5) signal transduction-related proteins, such as phospholipase C-like protein, 14-3-3 zeta, translationally controlled tumour protein and RNA binding motif protein. Taken together, these data support the idea that CO2-driven seawater acidification may affect protein expression in the crustacean A. sinica and possibly also in other species that feed on brine shrimp in the ecosystem, particularly marine food webs.


Assuntos
Artemia/fisiologia , Proteínas de Artrópodes/genética , Proteoma , Água do Mar/química , Animais , Artemia/genética , Proteínas de Artrópodes/metabolismo , Dióxido de Carbono/análise , Cromatografia Líquida , Eletroforese em Gel Bidimensional , Concentração de Íons de Hidrogênio , Espectrometria de Massas em Tandem
10.
Sci Rep ; 6: 28694, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27385304

RESUMO

White spot syndrome virus (WSSV) is a lethal pathogen of shrimp and many other crustaceans, including crayfish. However, the molecular mechanism underlying its cellular entry remains elusive due to the lack of shrimp cell lines for viral propagation. Crayfish hematopoietic tissue (Hpt) cell culture was recently established as a good model for WSSV infection study. Here, we showed that multiple endocytic routes, including clathrin-mediated endocytosis (CME), macropinocytosis and caveolae-mediated endocytosis, were indispensably employed for the viral entry into Hpt cell of the crayfish Cherax quadricarinatus. Intriguingly, cellular autophagic activity was positively correlated with efficient viral entry, in which a key autophagy-related protein, γ-aminobutyric acid receptor-associated protein (Cq-GABARAP), that not only localized but also co-localized with WSSV on the Hpt cell membrane, strongly facilitated WSSV entry by binding to the viral envelope VP28 in a CME-dependent manner that was negatively regulated by Cq-Rac1. Furthermore, cytoskeletal components, including Cq-ß-tubulin and Cq-ß-actin, bound to both recombinant rCq-GABARAP and WSSV envelope proteins, which likely led to viral entry promotion via cooperation with rCq-GABARAP. Even under conditions that promoted viral entry, rCq-GABARAP significantly reduced viral replication at an early stage of infection, which was probably caused by the formation of WSSV aggregates in the cytoplasm.


Assuntos
Proteínas de Artrópodes/fisiologia , Família da Proteína 8 Relacionada à Autofagia/fisiologia , Endocitose , Internalização do Vírus , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Astacoidea/citologia , Astacoidea/virologia , Autofagia , Células Cultivadas , Invaginações Revestidas da Membrana Celular/ultraestrutura , Invaginações Revestidas da Membrana Celular/virologia , Ligação Proteica , Proteínas do Envelope Viral/metabolismo , Replicação Viral
11.
Fish Shellfish Immunol ; 50: 288-96, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26845698

RESUMO

To elucidate proteomic changes of Hpt cells from red claw crayfish, Cherax quadricarinatus, we have carried out isobaric tags for relative and absolute quantitation (iTRAQ) of cellular proteins at both early (1 hpi) and late stage (12 hpi) post white spot syndrome virus (WSSV) infection. Protein database search revealed 594 protein hits by Mascot, in which 17 and 30 proteins were present as differentially expressed proteins at early and late viral infection, respectively. Generally, these differentially expressed proteins include: 1) the metabolic process related proteins in glycolysis and glucogenesis, DNA replication, nucleotide/amino acid/fatty acid metabolism and protein biosynthesis; 2) the signal transduction related proteins like small GTPases, G-protein-alpha stimulatory subunit, proteins bearing PDZ- or 14-3-3-domains that help holding together and organize signaling complexes, casein kinase I and proteins of the MAP-kinase signal transduction pathway; 3) the immune defense related proteins such as α-2 macroglobulin, transglutaminase and trans-activation response RNA-binding protein 1. Taken together, these protein information shed new light on the host cellular response against WSSV infection in a crustacean cell culture.


Assuntos
Proteínas de Artrópodes/genética , Astacoidea/imunologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/metabolismo , Astacoidea/genética , Astacoidea/virologia , Sistema Hematopoético/imunologia , Proteômica/métodos , Análise de Sequência de DNA
12.
Zhong Yao Cai ; 39(2): 245-9, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30080344

RESUMO

Objective: To discuss the suitable water and nitrogen management modes in cultivating Chuzhou Chrysanthemum morifolium. Methods: According to two-factors quadratic regression rotation experimental designs, the effect of water and nitrogen fertilizer coupling on water consumption and water use efficiency( WUE) of Chuzhou Chrysanthemum morifolium were studied by pot experiment. Results: The water consumption of Chuzhou Chrysanthemum morifolium in different growth stages had big variation, and the water consumption rate( WCR) of squaring stage was higher. There were remarkable effect of water and nitrogen coupling on water consumption of Chuzhou Chrysanthemum morifolium in different growth stages and WUE. Effect of water on water consumption of Chuzhou Chrysanthemum morifolium in different growth stages was higher than that of nitrogen fertilizer, but effect of nitrogen fertilizer on WUE were higher than that of water, and there were significant interaction between water and nitrogen. When the soil water and nitrogen fertilizer was- 0. 2063 level and 0. 4793 level, respectively, namely, keeping 71. 35% of the field water capacity and 0. 268 N / kg of nitrogen fertilizer, the WUE reached maximum up to 3. 435 g / kg per plant. Conclusion: Considered from WUE,the suitable management mode of water and nitrogen of Chuzhou Chrysanthemum morifolium is to keep low-to-middle soil water level and middle-to-high nitrogen fertilizer.


Assuntos
Chrysanthemum , Fertilizantes , Nitrogênio , Solo , Água
13.
Proteins ; 83(9): 1643-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26148303

RESUMO

The transporter MsbA is a kind of multidrug resistance ATP-binding cassette transporter that can transport lipid A, lipopolysaccharides, and some amphipathic drugs from the cytoplasmic to the periplasmic side of the inner membrane. In this work, we explored the allosteric pathway of MsbA from the inward- to outward-facing states during the substrate transport process with the adaptive anisotropic network model. The results suggest that the allosteric transitions proceed in a coupled way. The large-scale closing motions of the nucleotide-binding domains occur first, accompanied with a twisting motion at the same time, which becomes more obvious in middle and later stages, especially for the later. This twisting motion plays an important role for the rearrangement of transmembrane helices and the opening of transmembrane domains on the periplasmic side that mainly take place in middle and later stages respectively. The topological structure plays an important role in the motion correlations above. The conformational changes of nucleotide-binding domains are propagated to the transmembrane domains via the intracellular helices IH1 and IH2. Additionally, the movement of the transmembrane domains proceeds in a nonrigid body, and the two monomers move in a symmetrical way, which is consistent with the symmetrical structure of MsbA. These results are helpful for understanding the transport mechanism of the ATP-binding cassette exporters.


Assuntos
Transportadores de Cassetes de Ligação de ATP/química , Algoritmos , Proteínas de Bactérias/química , Modelos Moleculares , Conformação Proteica , Transportadores de Cassetes de Ligação de ATP/metabolismo , Anisotropia , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Simulação por Computador , Escherichia coli/metabolismo , Cinética , Movimento (Física) , Periplasma/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
14.
Planta Med ; 79(9): 731-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23700112

RESUMO

Icariin is a major active component isolated from the traditional Chinese herb Epimedium brevicornum, with a wide range of pharmacological and biological activities. In this paper, we investigated the effects of icariin on hyperlipidemia, and further evaluated whether icariin could improve unfavorable hemorheological parameters, attenuate platelet activation and facilitate the balance between plasmic plasminogen activator inhibitor-1 and tissue-type plasminogen activator activities in rabbits fed a high-cholesterol diet. Icariin reduced the levels of serum total cholesterol and low-density lipoprotein cholesterol, as well as the atherosclerotic burden. In addition, this compound has been found to improve the imbalance between plasmic plasminogen activator inhibitor-1 and tissue-type plasminogen activator activities, reduce platelet adhesiveness and aggregation and modulate unfavorable hemorheological variables in hypercholesterolemia. In conclusion, icariin has lipid-lowering effects and may be used in the treatment and prevention of thrombosis in the atherosclerotic process.


Assuntos
Anticolesterolemiantes/farmacologia , Aterosclerose/tratamento farmacológico , Fibrinolíticos/farmacologia , Flavonoides/farmacologia , Animais , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/patologia , Aterosclerose/sangue , Aterosclerose/fisiopatologia , Colesterol/sangue , LDL-Colesterol/sangue , Medicamentos de Ervas Chinesas/química , Hiperlipidemias/tratamento farmacológico , Masculino , Inibidor 1 de Ativador de Plasminogênio/sangue , Ativação Plaquetária/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Coelhos , Ativador de Plasminogênio Tecidual/sangue
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