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1.
Artigo em Inglês | MEDLINE | ID: mdl-38573076

RESUMO

An aerobic, non-motile, Gram-stain-positive bacterium, designated strain NEAU-Y5T, was isolated from a soil sample collected from Northeast Agricultural University, Heilongjiang province. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-Y5T belonged to the genus and showed high 16S rRNA sequence similarity to Isoptericola variabilis (98.9 %), Isoptericola nanjingensis (98.9 %), Isoptericola cucumis (98.5 %), Isoptericola hypogeus (98.5 %), Isoptericola dokdonensis (98.5 %), Isoptericola jiangsuensis (98.3 %), and Isoptericola halalbus (98.1 %), followed by other members of the genus Isoptericola (<98 %), and phylogenetically clustered with I. dokdonensis and I. jiangsuensis. Strain NEAU-Y5T was found to grow at 4-40 °C (optimum, 28 °C), pH 6.0-12.0 (optimum, pH 7.0), and tolerated 0-6 % NaCl (w/v). The cell-wall peptidoglycan type was l-Lys-d-Asp. The whole-cell hydrolysates contained glucose, galactose, and ribose. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, and glucosamine unknown phospholipid. Major fatty acids were anteiso-C15 : 0 and anteiso-C17 : 0. The predominant menaquinone was MK-9(H4). The DNA G+C content was 73.4 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between strain NEAU-Y5T and the type strains of the genus Isoptericola ranged from 18.6 to 23.5 % and from 77.3 to 81.6 %, respectively. Based on morphological, physiological, chemotaxonomic, and phylogenetic data, as well as digital DNA-DNA hybridization and average nucleotide identity values, the novel strain NEAU-Y5T could be differentiated from its closest relatives. Therefore, the strain represents a novel species of the genus Isoptericola, for which the name Isoptericola luteus sp. nov. is proposed. The type strain is NEAU-Y5T (=CCTCC AA 2019087T=DSM 110637T).


Assuntos
Actinomycetales , Solo , Humanos , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias , Nucleotídeos
2.
Sensors (Basel) ; 23(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37300022

RESUMO

Fault diagnosis is crucial for repairing aircraft and ensuring their proper functioning. However, with the higher complexity of aircraft, some traditional diagnosis methods that rely on experience are becoming less effective. Therefore, this paper explores the construction and application of an aircraft fault knowledge graph to improve the efficiency of fault diagnosis for maintenance engineers. Firstly, this paper analyzes the knowledge elements required for aircraft fault diagnosis, and defines a schema layer of a fault knowledge graph. Secondly, with deep learning as the main method and heuristic rules as the auxiliary method, fault knowledge is extracted from structured and unstructured fault data, and a fault knowledge graph for a certain type of craft is constructed. Finally, a fault question-answering system based on a fault knowledge graph was developed, which can accurately answer questions from maintenance engineers. The practical implementation of our proposed methodology highlights how knowledge graphs provide an effective means of managing aircraft fault knowledge, ultimately assisting engineers in identifying fault roots accurately and quickly.


Assuntos
Aeronaves , Reconhecimento Automatizado de Padrão , Engenharia , Heurística , Conhecimento
3.
Entropy (Basel) ; 22(7)2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-33286549

RESUMO

A simple and effective lattice-gas-automaton (LGA) economic model is proposed for the income distribution. It consists of four stages: random propagation, economic transaction, income tax, and charity. Two types of discrete models are introduced: two-dimensional four-neighbor model (D2N4) and D2N8. For the former, an agent either remains motionless or travels to one of its four neighboring empty sites randomly. For the latter, the agent may travel to one of its nearest four sites or the four diagonal sites. Afterwards, an economic transaction takes place randomly when two agents are located in the nearest (plus the diagonal) neighboring sites for the D2N4 (D2N8). During the exchange, the Matthew effect could be taken into account in the way that the rich own a higher probability of earning money than the poor. Moreover, two kinds of income tax models are incorporated. One is the detailed taxable income brackets and rates, and the other is a simplified tax model based on a fitting power function. Meanwhile, charity is considered with the assumption that a richer agent donates a part of his income to charity with a certain probability. Finally, the LGA economic model is validated by using two kinds of benchmarks. One is the income distributions of individual agents and two-earner families in a free market. The other is the shares of total income in the USA and UK, respectively. Besides, impacts of the Matthew effect, income tax and charity upon the redistribution of income are investigated. It is confirmed that the model has the potential to offer valuable references for formulating financial laws and regulations.

4.
Int J Mol Sci ; 20(5)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30813609

RESUMO

The lotus (Nelumbo Adans.) is a perennial aquatic plant with important value in horticulture, medicine, food, religion, and culture. It is rich in germplasm and more than 2000 cultivars have been cultivated through hybridization and natural selection. Microsporogenesis and male gametogenesis in the anther are important for hybridization in flowering plants. However, little is known about the cytological events, especially related to the stamen, during the reproduction of the lotus. To better understand the mechanism controlling the male reproductive development of the lotus, we investigated the flower structure of the Asian lotus (N. nucifera). The cytological analysis of anther morphogenesis showed both the common and specialized cytological events as well as the formation of mature pollen grains via meiosis and mitosis during lotus anther development. Intriguingly, an anatomical difference in anther appendage structures was observed between the Asian lotus and the American lotus (N. lutea). To facilitate future study on lotus male reproduction, we categorized pollen development into 11 stages according to the characterized cytological events. This discovery expands our knowledge on the pollen and appendage development of the lotus as well as improving the understanding of the species differentiation of N. nucifera and N. lutea.


Assuntos
Flores/citologia , Nelumbo/anatomia & histologia , Nelumbo/citologia , Parede Celular/ultraestrutura , Flores/ultraestrutura , Nelumbo/ultraestrutura , Pólen/citologia , Pólen/crescimento & desenvolvimento , Pólen/ultraestrutura
5.
Anal Biochem ; 534: 56-63, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28712944

RESUMO

In this study, a Fe3O4@Au-based pseudo-homogeneous electrochemical immunosensor was prepared for detection of alpha fetoprotein (AFP), a well-known hepatocellular carcinoma biomarker. The primary antibody (Ab1) was immobilized on Fe3O4@Au NPs as the capture probe. Horseradish peroxidase (HRP) and secondary antibody (Ab2) were conjugated on gold nanoparticles (GNPs) through electrostatic adsorption to form signal-amplifying labels. In the presence of AFP, a sandwich immunocomplex was formed via specific recognition of antigen-antibody in a Fe3O4@Au-basedpseudo-homogeneousreaction system. After the immunocomplex was captured to the surface of magnetic glassy carbon electrode (MGCE), the labeling HRP catalyzed the decomposition of H2O2, resulting in a substantial current for the quantitative detection of AFP. The amperometric (i-t) method was employed to record the response signal of the immunosensor based on the catalysis of the immobilized HRP toward the reduction of H2O2 with hydroquinone (HQ) as the redox mediator. Under the optimal conditions, the amperometric current response presented a linear relationship with AFP concentration over the range of 20 ng/mL-100 ng/mLwith a correlation coefficient of 0.9940, and the detection limit was 0.64 ng/mL at signal/noise [S/N] = 3. Moreover, the electrochemical immunosensor exhibited higher anti-interference ability, acceptable reproducibility and long-term stability for AFP detection.


Assuntos
Anticorpos/química , Óxido Ferroso-Férrico/química , Ouro/química , Peroxidase do Rábano Silvestre/química , Sondas Moleculares/química , alfa-Fetoproteínas/análise , Técnicas Eletroquímicas , Eletrodos , Peroxidase do Rábano Silvestre/metabolismo , Imunoensaio , Nanopartículas Metálicas/química
6.
Plant Cell Rep ; 36(2): 297-311, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27896424

RESUMO

KEY MESSAGE: Dynamic transcriptional changes of the host early responses genes were detected in PVY-resistant tobacco varieties infected with Potato virus Y; PVY resistance is a complex process that needs series of stress responses. Potato virus Y (PVY) causes a severe viral disease in cultivated crops, especially in Solanum plants. To understand the molecular basis of plant responses to the PVY stress, suppression subtractive hybridization (SSH) and microarray approaches were combined to identify the potentially important or novel genes that were involved in early stages (12 h, 1, 2, 3, 5, 8 days) of tobacco response to PVY infection. Dynamic changes of the host plant early responses to PVY infection on a transcriptional level were detected. In total, 167 different expressed ESTs were identified. The majority of genes involved in the metabolic process were found to be down-regulated at 12 h and 1 day, and then up-regulated at least one later period. Genes related to signaling and transcriptions were almost up-regulated at 12 h, 1 or 2 days, while stress response genes were almost up-regulated at a later stage. Genes involved in transcription, transport, cell wall, and several stress responses were found to have changed expression during the PVY infection stage, and numbers of these genes have not been previously reported to be associated with tobacco PVY infection. The diversity expression of these genes indicated that PVY resistance is a complex process that needs a series of stress responses. To resist the PVY infection, the tobacco plant has numerous active and silent responses.


Assuntos
Resistência à Doença/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Nicotiana/genética , Nicotiana/virologia , Doenças das Plantas/genética , Potyvirus/fisiologia , Etiquetas de Sequências Expressas , Análise de Sequência com Séries de Oligonucleotídeos , Doenças das Plantas/virologia , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Transdução de Sinais/genética , Estresse Fisiológico/genética , Nicotiana/fisiologia , Fatores de Transcrição/metabolismo
7.
Mol Genet Genomics ; 290(4): 1367-77, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25876163

RESUMO

Tropane alkaloids (TAs) such as anisodamine, anisodine, hyoscyamine and scopolamine are extensively used in clinical practice as anticholinergic agents. Anisodus acutangulus produces TAs in root tissue, and although several genes involved in scopolamine biosynthesis have been cloned, yet the biosynthetic pathway of TAs remains poorly understood. To further understand TAs biosynthesis mechanism, transcriptome analysis with deep RNA sequencing in A. acutangulus roots was performed in this study; 48 unigenes related to tropane, piperidine and pyridine alkaloid biosynthesis, 145 linked to the distribution of arginine to TAs biosynthesis, and 86 categorized to terpenoid backbone biosynthesis have been identified in pathway enrichment analyses with eukaryotic orthologous groups (KOG) and Kyoto encyclopedia of genes and genomes. Additionally, 82 unigenes annotated as cytochrome P450 family members seemed to be involved in secondary metabolism. Genes encoding littorine mutase/monooxygenase (CYP80F1), diamine oxidase (DAO), alcohol dehydrogenase (ADH) and aromatic amino acid aminotransferase (ArAT) may also play roles in TAs biosynthetic pathways. Furthermore, over 1,000 unigenes were identified as potential transcription factors of WRKY, AP2/ERF, MYB and bHLH families, which would be helpful to understand transcriptional regulation of secondary metabolite biosynthesis. These data enable novel insights into A. acutangulus transcriptome, updating the knowledge of TAs biosynthetic mechanism at molecular level.


Assuntos
Alcaloides/biossíntese , Regulação da Expressão Gênica de Plantas , Solanaceae/genética , Transcriptoma/genética , Tropanos/metabolismo , Vias Biossintéticas/genética , Sistema Enzimático do Citocromo P-450/classificação , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA , Solanaceae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Biotechnol Appl Biochem ; 62(1): 24-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24779358

RESUMO

Tanshinone is a group of active diterpenes, which are widely used in the treatment of cardiovascular disease. In this study, methyl jasmonate (MJ) and salicylic acid (SA) were used to investigate their effects on tanshinone accumulation and biosynthetic gene expression in the hairy roots of geranylgeranyl diphosphate synthase (SmGGPPS) overexpression line (G50) in Salvia miltiorrhiza. High-performance liquid chromatography analysis showed that total tanshinone content in G50 was obviously increased by 3.10-fold (11.33 mg/g) with MJ at 36 H and 1.63 times (5.95 mg/g) after SA treatment for 36 H in comparison with their mimic treatment control. Furthermore, quantitative reverse-transcription PCR analysis showed that the expression of isopentenyl-diphosphate delta-isomerase (SmIPPI), SmGGPPS, copalyl diphosphate synthase (SmCPS), and kaurene synthase-like (SmKSL) increased significantly with MJ treatment. However, the expression of SmIPPI reached the highest level at 144 H, whereas those of SmGGPPS, SmCPS, and SmKSL only increased slightly with SA treatment. The two elicitor treatments suggested that tanshinone accumulation positively correlated to the expression of key genes such as SmGGPPS, SmCPS, and SmKSL. Meanwhile, the study also indicated that it was a feasible strategy to combine elicitor treatment with transgenic technology for the enhancement of tanshinone, which paved the way for further metabolic engineering of tanshinone biosynthesis.


Assuntos
Abietanos/biossíntese , Acetatos/farmacologia , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oxilipinas/farmacologia , Ácido Salicílico/farmacologia , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/metabolismo , Técnicas de Cultura de Tecidos , Plantas Geneticamente Modificadas , Salvia miltiorrhiza/efeitos dos fármacos , Salvia miltiorrhiza/crescimento & desenvolvimento
9.
Funct Integr Genomics ; 14(3): 603-15, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24913677

RESUMO

Tanshinone is widely used for treatment of cardio-cerebrovascular diseases with increasing demand. Herein, key enzyme genes SmHMGR (3-hydroxy-3-methylglutaryl CoA reductase) and SmDXR (1-deoxy-D-xylulose 5-phosphate reductoisomerase) involved in the tanshinone biosynthetic pathway were introduced into Salvia miltiorrhiza (Sm) hairy roots to enhance tanshinone production. Over-expression of SmHMGR or SmDXR in hairy root lines can significantly enhance the yield of tanshinone. Transgenic hairy root lines co-expressing HMGR and DXR (HD lines) produced evidently higher levels of total tanshinone (TT) compared with the control and single gene transformed lines. The highest tanshinone production was observed in HD42 with the concentration of 3.25 mg g(-1) DW. Furthermore, the transgenic hairy roots showed higher antioxidant activity than control. In addition, transgenic hairy root harboring HMGR and DXR (HD42) exhibited higher tanshinone content after elicitation by yeast extract and/or Ag(+) than before. Tanshinone can be significantly enhanced to 5.858, 6.716, and 4.426 mg g(-1) DW by YE, Ag(+), and YE-Ag(+) treatment compared with non-induced HD42, respectively. The content of cryptotanshinone and dihydrotanshinone was effectively elevated upon elicitor treatments, whereas there was no obvious promotion effect for the other two compounds tanshinone I and tanshinone IIA. Our results provide a useful strategy to improve tanshinone content as well as other natural active products by combination of genetic engineering with elicitors.


Assuntos
Abietanos/biossíntese , Aldose-Cetose Isomerases/genética , Hidroximetilglutaril-CoA Redutases/genética , Salvia miltiorrhiza/genética , Abietanos/química , Aldose-Cetose Isomerases/biossíntese , Compostos de Bifenilo/química , Fármacos Cardiovasculares/química , Fármacos Cardiovasculares/metabolismo , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/metabolismo , Expressão Gênica , Hidroximetilglutaril-CoA Redutases/biossíntese , Oxirredução , Picratos/química , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Salvia miltiorrhiza/enzimologia
10.
Biotechnol Appl Biochem ; 59(5): 323-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23586908

RESUMO

Hepatocellular carcinoma (HCC) is a common clinical primary malignant tumor; however, efficient drugs for the treatment of HCC are still lacking at the present time. To develop a new approach for liver cancer therapy, we designed a chimeric gene (his-HR) encoding a single-chain variable fragment of human HAb25 (hHscFv) fused to a cytotoxic ribonuclease from Rana catesbeiana (RC-RNase) and expressed the corresponding fusion protein in transgenic tobacco (Nicotiana tabacum). Eleven positive transgenic plant lines were identified from 204 regenerated tobacco plants by PCR and Southern blot analysis, and the immunocompetence of the recombinant his-HR protein was confirmed by Western blotting. The expression levels of his-HR protein ranged from 0.75 to 1.99 µg/g in the fresh tobacco leaves. To characterize the bifunction of the expressed his-HR protein in tobacco, binding specificity and cell toxicity to several cell lines were examined by the indirect immunocytochemical streptavidin-biotin complex method and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. Data indicated that the his-HR protein had stronger specific binding affinity to HepG2 (human liver HCC cell line) than to the other tumor cell lines and normal liver cell line, and the capacity to kill the HCC cell lines SMMC7721 and HepG2 with an half maximal inhibiting concentration of 2.0 and 2.4 nM, respectively. The results suggest that recombinant bifunctional his-HR protein derived from transgenic plants may provide a novel strategy to treat HCC in the future.


Assuntos
Proteínas de Anfíbios/genética , Carcinoma Hepatocelular/patologia , Endorribonucleases/genética , Neoplasias Hepáticas/patologia , Nicotiana/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Anticorpos de Cadeia Única/genética , Agrobacterium/genética , Anticorpos Monoclonais Humanizados/genética , Linhagem Celular Tumoral , Genoma de Planta/genética , Humanos , Plantas Geneticamente Modificadas , Transformação Genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-35162604

RESUMO

The antibiotic mycelial residue (AMR) generated from cephalosporin C production is a hazardous organic waste, which is usually disposed of by landfilling that causes potential secondary environmental pollution. AMR combustion can be an effective method to treat AMR. In order to develop clean combustion technologies for safe disposal and energy recovery from various AMRs, the emission characteristics of NOx and SO2 from AMR combustion were studied experimentally in this work. It was found that the fuel-N is constituted by 85% protein nitrogen and 15% inorganic nitrogen, and the fuel-S by 78% inorganic sulfur and 22% organic sulfur. Nitrogen oxide emissions mainly occur at the volatile combustion stage when the temperature rises to 400 °C, while the primary sulfur oxide emission appears at the char combustion stage above 400 °C. Increasing the combustion temperature and airflow cause higher NOx emissions. High moisture content in AMR can significantly reduce the NOx emission by lowering the combustion temperature and generating more reducing gases such as CO. For the SO2 emission, the combustion temperature (700 to 900 °C), airflow and AMR water content do not seem to exhibit obvious effects. The presence of CaO significantly inhibits SO2 emission, especially for the SO2 produced during the AMR char combustion because of the good control effect on the direct emission of inorganic SO2. Employing air/fuel staging technologies in combination with in-situ desulfurization by calcium oxide/salts added in the combustor with operation temperatures lower than 900 °C should be a potential technology for the clean disposal of AMRs.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Antibacterianos , Gases , Óxido Nítrico , Óxidos de Nitrogênio/análise
12.
Mol Biol Rep ; 38(3): 1813-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20872075

RESUMO

Tocochromanols, usually known as vitamin E, play a crucial role in human and animal nutrition. The enzyme homogentisate phytyltransferase (HPT) performs the first committed step of the vitamin E biosynthetic pathway. The full-length cDNA encoding HPT was isolated from Lactuca sativa L. by rapid amplification of cDNA ends (RACE). The cDNA, designated as LsHPT, was 1,670 bp long containing an open reading frame (ORF) of 1,185 bp which encoded a protein of 395 amino acids. Sequence analysis indicated that the deduced protein, named as LsHPT, shared high identity with other dicotyledonous HPTs. Real-time fluorescent quantitative PCR (qPCR) analysis revealed that LsHPT was preferentially expressed in mature leaves compared with other tissues. When lettuce plants were subjected to drought and high-light stress treatments, LsHPT expression was markedly increased. Expression of LsHPT in Arabidopsis showed that LsHPT could enhance the α-tocopherol biosynthesis in Arabidopsis. Transient expression of LsHPT via agroinfiltration resulted in 9-fold increase in LsHPT mRNA level and nearly 18-fold enhancement in α-tocopherol content compared with the negative controls.


Assuntos
Alquil e Aril Transferases/genética , Genes de Plantas/genética , Lactuca/enzimologia , Lactuca/genética , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Secas , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Lactuca/efeitos da radiação , Luz , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rhizobium/fisiologia , Rhizobium/efeitos da radiação , Análise de Sequência de DNA , Estresse Fisiológico/genética , Estresse Fisiológico/efeitos da radiação , Transformação Genética/efeitos da radiação
13.
Plants (Basel) ; 10(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34451674

RESUMO

The lotus (Nelumbo Adans.) is an important aquatic plant with ornamental, medicinal and edible values and cultural connotations. It has single-, semi-double-, double- and thousand-petalled types of flower shape and is an ideal material for developmental research of flower doubling. The lotus is a basal eudicot species without a morphological difference between the sepals and petals and occupies a critical phylogenetic position in flowering plants. In order to investigate the genetic relationship between the sepals and petals in the lotus, the class E genes which affect sepal formation were focused on and analyzed. Here, SEPALLATA 1(NnSEP1) and its homologous genes AGAMOUS-LIKE MADS-BOXAGL9 (NnAGL9) and MADS-BOX TRANSCRIPTION FACTOR 6-like (NnMADS6-like) of the class E gene family were isolated from the flower buds of the Asian lotus (Nelumbo nucifera Gaertn.). The protein structure, subcellular localization and expression patterns of these three genes were investigated. All three genes were verified to locate in the nucleus and had typical MADS-box characteristics. NnSEP1 and NnMADS6-like were specifically expressed in the sepals, while NnAGL9 was highly expressed in the petals, suggesting that different developmental mechanisms exist in the formation of the sepals and petals in the lotus. The significant functional differences between NnSEP1, NnMADS6-like and NnAGL9 were also confirmed by a yeast two-hybrid assay. These results expand our knowledge on the class E gene family in sepal formation and will benefit fundamental research on the development of floral organs in Nelumbo.

14.
Biotechnol Appl Biochem ; 52(Pt 4): 303-12, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18752465

RESUMO

Talpha1 (thymosin alpha1), an immune booster, plays an important role in the maturation, differentiation and function of T-cells. It can also activate the production of cytokines in dendritic cells. Talpha1 is one of two thymosin proteins that have potential future clinical applications. In order to express Talpha1 protein in plants, we designed and synthesized the Talpha1 gene according to the plant codon usage bias and created a novel 4 x Talpha1 concatemer (four copies of the Talpha1 gene arranged end-to-end in tandem, designated 4 x Talpha1). Subsequently, a plant binary expression vector, PG-pRD12-4 x Talpha1, was constructed and introduced into tomato via Agrobacterium tumefaciens-mediated transformation. Through selection, 54 regenerated tomato plants resistant to kanamycin were obtained, and four transgenic tomato plants were further confirmed by PCR and Southern blotting. RT-PCR (reverse transcription-PCR) analysis showed that the 4 x Talpha1 gene was transcribed specifically in tomato [Solanum lycopersicum (formerly Lycopersicon esculentum)] fruits. ELISA analysis showed that the content of the 4 x Talpha1 protein reached a maximum of 6.098 microg/g fresh weight in mature tomato fruit. Western-blot analysis further confirmed the expression of 4xTalpha1 protein in transgenic tomato fruits. The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay showed the 4 x Talpha1 protein derived from transgenic tomatoes exhibited bioactivity that can stimulate the proliferation of mice splenic lymphocytes in vitro, and the specific activity of Talpha1 protein from the artificial system was higher than that from the synthetic Escherichia coli system. This study is the first to report successful expression of bioactive Talpha1 in plants, and also it will provide the basis for further development of the plant system to produce Talpha1.


Assuntos
Frutas/genética , Frutas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Engenharia de Proteínas/métodos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Timosina/análogos & derivados , Regulação da Expressão Gênica de Plantas/fisiologia , Humanos , Timalfasina , Timosina/genética , Timosina/isolamento & purificação , Timosina/metabolismo
15.
J Am Soc Mass Spectrom ; 19(4): 569-85, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18296063

RESUMO

The fragmentation characteristics of monohydroxyeicosatetraenoic acids and dihydroxy- and trihydroxyeicosatrienoic acids were investigated by electrospray ionization Fourier transform ion cyclotron resonance (FTICR) mass spectrometry using sustained off-resonance irradiation collision-induced dissociation (SORI-CID) and infrared multiphoton dissociation (IRMPD). The fragmentation patterns of these compounds were associated with the number and positions of the hydroxyl substituents. The fragmentation is more complicated with increasing number of the hydroxyl groups of the compounds. In general, the major carbon-carbon cleavage of [M - H](-) ions occurred at the alpha-position to the hydroxyl group, and the carbon-carbon cleavage occurred when there was a double-bond at the beta-position to the hydroxyl group. SORI-CID and IRMPD produced some common fragmentation patterns; however, each technique provided some unique patterns that are useful for structural identification of these compounds. This study demonstrated the application of FTICR via the identification of regioisomers of trihydroxyeicosatrienoic acids in rabbit aorta samples.


Assuntos
Ácidos Hidroxieicosatetraenoicos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas em Tandem , Animais , Animais Recém-Nascidos , Aorta/química , Aorta/efeitos dos fármacos , Aorta/metabolismo , Calcimicina/farmacologia , Ciclotrons , Radical Hidroxila/química , Indometacina/farmacologia , Coelhos
16.
Biotechnol Appl Biochem ; 49(Pt 1): 51-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17523920

RESUMO

Talpha1 (thymosin alpha 1) is important in treating immunodeficiency and other diseases. In order to study the feasibility of expressing Talpha1 in plants, as the first attempt, we designed and synthesized the Talpha1 gene according to the plant codon usage preference and constructed the 4xTalpha1 concatemer (four copies of a DNA sequence arranged end-to-end in tandem). The latter was inserted into Escherichia coli expression vector pQE30, resulting in a recombinant plasmid that was subsequently transformed into E. coli M15. The 4xTalpha1 concatemer protein was successfully expressed in E. coli in a soluble form. The expressed protein was purified and its bioactivity was analysed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay. Preliminary results showed that the 4xTalpha1 concatemer protein could stimulate the mice spleen lymphocyte proliferation. This is the first report on the expression of 4xTalpha1 concatemer that was synthesized according to plant codon usage preference in an E. coli expression system. The present study provides the basis for expressing the synthesized active Talpha1 gene in plants in the future.


Assuntos
Clonagem Molecular , Escherichia coli , Timosina/análogos & derivados , Animais , Reatores Biológicos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Escherichia coli/genética , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Plantas Geneticamente Modificadas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Timalfasina , Timosina/biossíntese , Timosina/genética
17.
Biosens Bioelectron ; 102: 560-567, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29220804

RESUMO

Cholesterol is an essential ingredient in mammals, and serum cholesterol is a major component of atherosclerotic plaques. The level of cholesterol in human serum has become an important index for clinical diagnosis and prevention of cardiovascular disease. In this paper, a simple and ultrasensitive cholesterol biosensor based on graphene oxide (GO) and gold nanoparticles (Au NPs) co-mediated enzymatic silver deposition was designed by immobilizing cholesterol oxidase (CHOD), cholesterol esterase (CHER) and GO onto the surface of Au NPs modified screen-printed carbon electrode (SPE). Under the synergistic effect of CHER, CHOD and GO, the cholesterol was hydrolyzed to generate hydrogen peroxide, which can reduce the silver (Ag) ions in the solution to metallic Ag which deposited on the surface of Au NPs modified SPE. The ultrasensitive detection of cholesterol was achieved by anodic stripping voltammetry measurement of the enzymatically deposited Ag. Under optimal conditions, the anodic stripping peak current of Ag increased with the increasing cholesterol concentration in the range from 0.01µg/mL to 5000µg/mL with a limit of detection of 0.001µg/mL (S/N = 3). In addition, the ultrasensitive cholesterol biosensor exhibited higher specificity, acceptable reproducibility and excellent recoveries for cholesterol detection.


Assuntos
Técnicas Biossensoriais/métodos , Colesterol/isolamento & purificação , Técnicas Eletroquímicas/métodos , Colesterol/química , Colesterol Oxidase/química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Óxidos/química
18.
Biotechnol Appl Biochem ; 48(Pt 2): 101-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17868024

RESUMO

In the present study, a plant binary expression vector PG-pRD12-hFIX (where PG is polygalacturonase) harbouring the hFIX (human coagulation Factor IX) gene was constructed and introduced into tomato (Lycopersicon esculentum) via Agrobacterium tumefaciens-mediated transformation. After kanamycin selection, 32 putative independent transgenic tomato plants were regenerated. PCR and Southern-blot analyses confirmed the transgenic status of some plants. RT (reverse transcription)-PCR analysis for the expression of the introduced gene (hFIX) demonstrated that the hFIX gene was expressed specifically in fruits of the tomato. Western-blot analysis confirmed the presence of a 56 kDa band specific to hFIX in the transformed tomatoes. ELISA results showed that the expression of hFIX protein reached a maximum of 15.84 ng/g fresh weight in mature fruit. A blood-clotting assay demonstrated the clotting activity of the expressed hFIX protein in transgenic tomato fruits. This is the first report on the expression of hFIX in plants, and our research provides potentially valuable knowledge for further development of the plant-derived therapeutic proteins.


Assuntos
Fator IX/química , Fator IX/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Engenharia de Proteínas/métodos , Solanum lycopersicum/fisiologia , Fator IX/genética , Humanos , Proteínas Recombinantes/metabolismo
19.
Mater Sci Eng C Mater Biol Appl ; 77: 1-8, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28531970

RESUMO

Cholesterol is one of the essential structural constituents of cell membranes. Determination of cholesterol is of great importance in clinical analysis because the level of cholesterol in serum is an indicator in the diagnosis and prevention of heart diseases. In this work, a simple and ultrasensitive cholesterol biosensor based on enzymatic silver deposition was designed by immobilizing cholesterol oxidase (CHOD) and cholesterol esterase (CHER) onto the surface of gold nanoparticles (Au NPs) modified screen-printed carbon electrode (SPE). By the catalytic action of CHER and CHOD, the cholesterol was hydrolyzed to generate hydrogen peroxide (H2O2) which can reduced the silver (Ag) ions in the solution for the deposition of metallic Ag on the surface of Au NPs modified SPE. The ultrasensitive detection of cholesterol was achieved by anodic stripping voltammetry (ASV) measurement of the enzymatically deposited Ag. The influence of relevant experimental variables was optimized. The anodic stripping peak current of Ag depended linearly on the concentration of cholesterol in the range of 5-5000µg/mL with the regression correlation coefficient of 0.9983. A detection limit of 3.0µg/mL was attained by 3 sigma-rule. In addition, the ultrasensitive cholesterol biosensor exhibited higher specificity, acceptable reproducibility and excellent recoveries for cholesterol detection.


Assuntos
Técnicas Biossensoriais , Carbono , Colesterol , Eletrodos , Ouro , Peróxido de Hidrogênio , Nanopartículas Metálicas , Reprodutibilidade dos Testes , Prata
20.
Zhonghua Xin Xue Guan Bing Za Zhi ; 34(2): 99-102, 2006 Feb.
Artigo em Zh | MEDLINE | ID: mdl-16626571

RESUMO

OBJECTIVE: To investigate the safety and efficacy of intracoronary transplantation of G-CSF mobilized autologous peripheral blood stem cells in patients with acute myocardial infarction (AMI). METHODS: Patients with AMI were randomly assigned to receive intracoronary PBSCs transplantation following bone marrow cells mobilization by granulocyte colony-stimulating factor (300-600 microg/day subcutaneously for 5 days) in addition to standard therapy (standard drug therapy and PCI, PBSCs transplantation group, n = 35) or standard therapy (standard drug therapy and PCI, n = 35). One day after G-CSF treatment was finished the patient's mononuclear cells were harvested by Baxter CS 3000 blood cell separator in a volume of 57 ml and then transferred into the infarct related artery by occluding the over the wire balloon and infusing artery through balloon center lumen. Complications during intervention and left ventricular function at baseline and 6 months thereafter were monitored. RESULTS: No severe side effects of G-CSF treatment could be observed. Malignant arrhythmias were not observed either. Left ventricular function was significantly improved 6 months after G-CSF mobilized autologous peripheral blood stem cell transplantation compared to baseline (global left ventricular function ejection fraction: 57.1 +/- 7.8 vs. 50.0 +/- 8.2%, P < 0.0001; WMSI: 1.101 +/- 0.118 vs. 1.219 +/- 0.190, P < 0.0001; left end-systolic volume: 52.6 +/- 20.3 vs. 63.8 +/- 23.9 ml, P = 0.01 and left end-diastolic volume: 119.2 +/- 30.3 vs. 134.2 +/- 36.7 ml, P = 0.07) while these parameters remained unchanged in the control group. CONCLUSION: The present study demonstrates that G-CSF mobilized autologous intracoronary PBSCs transplantation is a safe and feasible treatment for patients with AMI and global left ventricular function is improved and left ventricular remodeling attenuated at six-month follow-up.


Assuntos
Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/métodos , Infarto do Miocárdio/terapia , Transplante de Células-Tronco de Sangue Periférico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/cirurgia , Transplante Autólogo , Resultado do Tratamento
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