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1.
Comput Intell Neurosci ; 2021: 3735104, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34471406

RESUMO

How to effectively improve the effectiveness of art teaching has always been one of the hot topics concerned by all sectors of society. Especially, in art teaching, situational interaction helps improve the atmosphere of art class. However, there are few attempts to quantitatively evaluate the aesthetics of ink painting. Ink painting expresses images through ink tone and stroke changes, which is significantly different from photos and paintings in visual characteristics, semantic characteristics, and aesthetic standards. For this reason, this study proposes an adaptive computational aesthetic evaluation framework for ink painting based on situational interaction using deep learning techniques. The framework extracts global and local images as multiple input according to the aesthetic criteria of ink painting and designs a model named MVPD-CNN to extract deep aesthetic features; finally, an adaptive deep aesthetic evaluation model is constructed. The experimental results demonstrate that our model has higher aesthetic evaluation performance compared with baseline, and the extracted deep aesthetic features are significantly better than the traditional manual design features, and its adaptive evaluation results reach a Pearson height of 0.823 compared with the manual aesthetic. In addition, art classroom simulation and interference experiments show that our model is highly resistant to interference and more sensitive to the three painting elements of composition, ink color, and texture in specific compositions.


Assuntos
Pinturas , Simulação por Computador , Estética , Redes Neurais de Computação , Semântica
2.
Funct Plant Biol ; 46(11): 967-985, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31288904

RESUMO

A field experiment was conducted on Alhagi sparsifolia Shap. with a long-term clipping history (5-8 years) to investigate the adaptation strategy of A. sparsifolia to long-term clipping. The present study found that long-term clipping can reduce self-shading and increase the photosynthesis rate (Pn) in May. During the whole growth season, clipped plants can maintain a high Pn with less variation, which we denote as a 'stable photosynthesis strategy'. Although Pn in unclipped plants was higher than in the long-term clipping treatment in August, clipped plants accumulated more carbohydrates in shoots. The enhanced amount of carbohydrates could be correlated with the greater amount of lignin synthesis in stems. Therefore, long-term clipping induced the transition of A. sparsifolia from herbs to shrubs. After long-term clipping, plants allocated more resources to plant defence against stress, whereas the ratio of resources allocated to leaf growth decreased. Consequently, photosynthesis in long-term clipped plants decreased in August. In PSII, the energy used for both photochemical quenching and non-photochemical quenching decreased in the clipped plants during the early stage of the growth season. In addition, due to the lower stomatal conductance (gs), clipped plants retained more water in their leaves and suffered less water stress. Thus, clipped plants produced less reactive oxygen species (ROS), which in turn, delayed leaf senescence. Plants also exhibited over-compensatory growth after long-term clipping, but this phenomenon was not caused by the increase in specific leaf area (SLA). The stable photosynthesis strategy helped to extend the lifespan of plants in the growth season and improve their adaptation to light, temperature, and water stress.


Assuntos
Fabaceae , Fotossíntese , Carboidratos , Folhas de Planta , Água
3.
Orthop Surg ; 10(4): 296-305, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30402963

RESUMO

OBJECTIVE: To compare postoperative imaging results, clinical outcomes and complications between the multifidus muscle bundle (MMB) approach and the conventional open (CO) approach in one-level posterior lumbar interbody fusion (PLIF). METHODS: Based on the inclusion and exclusion criteria, 201 of 351 patients in our hospital were enrolled in this prospective study and underwent MMB-PLIF or CO-PLIF randomly: 111 patients in the MMB-PLIF group and 90 patients in the CO-PLIF group. A total of 100 patients failed to be followed up in the following 7-9 years. Therefore, in this study, 52 patients of the MMB group and 49 patients of the CO group were included. We evaluated the differences in terms of multifidus atrophy rate, intervertebral disc height and segmental lordosis restoration of the operation segment, lumbar lordosis restoration, fusion rate, visual analogue scale (VAS) for back and leg pain, Oswestry disability index (ODI), complication rates, and patient satisfaction rates between the two groups. Correlation between multifidus muscle degeneration and the incidence of complications was investigated, and we compared the multifidus muscle degeneration rate between patients with or without intractable back pain or adjacent segment degeneration. RESULTS: There were no significant differences in age, sex, body mass index (BMI), diagnosis, segments distribution, and mean follow-up time between the MMB-PLIF group and the CO-PLIF group. In addition, no differences regarding sex, age, or BMI were found between the lost follow-up group and the successful follow-up group. In regard to imaging and clinical evaluation, at the final follow-up, there were significant differences in multifidus atrophy rates (27.0% ± 6.8% vs 38.7% ± 10.9%), lumbar lordosis restoration (4.6° ± 2.5° vs 3.0° ± 1.9°), postoperative VAS for back pain (1.1 ± 0.9 vs 1.8 ± 1.2), ODI (7.7 ± 5.0 vs 12.4 ± 6.7), and patient satisfaction rates (86.5% vs 61.2%) between MMB-PLIF and CO-PLIF groups. However, there were no significant differences in segmental lordosis, intervertebral height restoration, postoperative VAS for leg pain or fusion rate between the two groups. In regards to complications, there were significant differences in the incidence of adjacent segment degeneration (3.8% vs 14.3%), intractable back pain (3.8% vs 22.4%), and residual neurological symptoms (5.8% vs 20.4%) between the two groups (P < 0.05) at the final follow-up. In addition, patients with adjacent segment degeneration and intractable back pain were observed with more significant multifidus muscle atrophy than those without these two complications (31.9% ± 1.1% vs 39.6% ± 2.1% and 30.9% ± 1.1% vs 42.8% ± 2.1%). CONCLUSION: Compared with CO-PLIF, MMB-PLIF had advantages in relation to protection of the multifidus muscle, better maintenance of lumbar lordosis, reduced lower back pain and ODI score, fewer complications, and a higher patient satisfaction rate. Protection of the multifidus muscle in lumbar surgery is an important aspect of minimally invasive surgery.


Assuntos
Vértebras Lombares/cirurgia , Músculos Paraespinais/cirurgia , Fusão Vertebral/métodos , Idoso , Dor nas Costas/etiologia , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/etiologia , Medição da Dor/métodos , Satisfação do Paciente , Parafusos Pediculares , Complicações Pós-Operatórias , Estudos Prospectivos , Radiografia , Fusão Vertebral/efeitos adversos
4.
Orthop Surg ; 10(4): 306-311, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30474324

RESUMO

OBJECTIVE: Turnover of cartilage endplate extracellular matrix (ECM) may play an important role in disc degeneration and low back pain (LBP). However, the expression pattern of pro-inflammatory factors, matrix metalloproteinases (MMP), and tissue inhibitors of metalloproteinases (TIMP) in the cartilage endplates (CEP) of intervertebral discs (IVD) is not understood. We aimed to examine the transcriptional levels of MMP, TIMP, and interleukins (IL), and the correlations between them. METHODS: Thirty degenerated cartilage endplate samples from patients with LBP who underwent lumbar fusion surgery were included in the degenerated group. Ten patients without LBP history who underwent lumbar surgery because of vertebral burst fractures were included in the control group. The degenerative severity of the samples was evaluated by MRI, and hematoxylin-eosin and safranin O-fast green (SO-FG) staining. Real-time polymerase chain reaction (RT-PCR) was used to detect the mRNA levels of MMP-1, MMP-3, MMP-9, MMP-13, TIMP-1, TIMP-2, TIMP-3, IL-1α, IL-1ß, and IL-6. The correlations between the levels of these genes were tested using Spearman's rho test. RESULTS: Hematoxylin-eosin and SO-FG staining confirmed a decrease in cell number and proteoglycans in the degenerated cartilage endplate. MRI showed significant signal changes in degenerated cartilage endplates. Patients in the degenerated group showed a higher rate of endplate Modic changes when compared with the control group. MMP-3, MMP-9, TIMP-3, IL-1α, and IL-1ß were elevated with statistical significance, while MMP-1, MMP-13, TIMP-1, TIMP-2, and IL-6 were changed without statistical significance or remained unchanged. Expression of MMP-3 was positively correlated with IL-1α (Spearman coefficient, 0.486; P < 0.05); expression of TIMP-3 was positively correlated with MMP-9, IL-1α, and IL-1ß (Spearman coefficient, 0.577, 0.407, and 0.571, respectively; P < 0.05). CONCLUSION: MMP-3, MMP-9, TIMP-3, IL-1α, and IL-1ß may play a role in the process of cartilage endplate degeneration. MMP-3 may be regulated by IL-1α, and TIMP-3 might be associated with MMP-9 and regulated by IL-1α and IL-1ß.


Assuntos
Cartilagem/metabolismo , Interleucinas/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Metaloproteinases da Matriz/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Adulto , Cartilagem/diagnóstico por imagem , Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Interleucinas/genética , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/cirurgia , Imageamento por Ressonância Magnética , Masculino , Metaloproteinases da Matriz/genética , Pessoa de Meia-Idade , RNA Mensageiro/genética , Radiografia , Fusão Vertebral , Inibidores Teciduais de Metaloproteinases/genética
5.
Ying Yong Sheng Tai Xue Bao ; 24(10): 2926-32, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24483089

RESUMO

By using acetylene inhibition method, this paper studied the soil denitrifying enzyme activity (DEA) and its affecting factors in the riparian zone with different land use types (cropland riparian, forested riparian, and grassy riparian zones) in Chongming Island, Shanghai of China. The riparian soil DEA was (0.69 +/- 0.11)--(134.93 +/- 33.72) microg N x kg(-1) x h(-1), which differed obviously among different land types, with a decreasing trend of forested riparian zone > cropland riparian zone > grassy riparian zone. The soil DEA was significantly (P < 0.05) higher in 0-10 cm in 10-30, 30-50, and 50-70 cm layers. There were significant positive relationships between soil DEA and soil TOC, TN, and NO(3-)-N (P < 0.01). Land use change mainly altered the soil natural structure and soil physical and chemical properties, decreased the accumulation of soil organic carbon, and affected the soil nitrogen transformation, and thus, inhibited the occurrence of riparian soil denitrification.


Assuntos
Desnitrificação/fisiologia , Ecossistema , Microbiologia do Solo , Solo/química , China , Monitoramento Ambiental , Enzimas/metabolismo , Nitrogênio/metabolismo , Óxido Nitroso/metabolismo , Urease/metabolismo
6.
J Enzyme Inhib Med Chem ; 22(2): 247-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17518353

RESUMO

The penta-N-acetyl-chitopentaose 2 has been prepared by using recombinant E. coli strains harboring the nodC gene (encoding chitooligosaccharide synthase) from Azorhizobium caulinodans. Then, the deacetylase NodB removed the N-acetyl moiety from the nonreducing terminus of 2 to give tetra-N-acetyl-chitopentaose 3. N-Acylation of 3 with stearyl chloride was performed in DMF containing water and provided the corresponding lipo-chitopentaose nodulation factor 4. A binding chitinase assay indicated that 4 was much more stable than 3.


Assuntos
Quitinases/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Acilação , Amidoidrolases/química , Azorhizobium caulinodans/enzimologia , Azorhizobium caulinodans/genética , Proteínas de Bactérias/química , Escherichia coli/genética , Engenharia Genética/métodos , Glucosídeos/biossíntese , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo
7.
Appl Biochem Biotechnol ; 136(1): 17-22, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17416974

RESUMO

Fluorophore-assisted carbohydrate electrophoresis (FACE) is a straightforward, sensitive method for determining the presence and relative abundance of individual (oligo)saccharide in a(n) (oligo)saccharide mixture. The single terminal aldehydes of (oligo)saccharides were tagged with the charged fluorophore 8-aminonaphthalene-1,3,6-trisulfonate (ANTS), and separated with high resolution on the basis of size by polyacrylamide gel electrophoresis. ANTS fluorescence labeling is not biased by (oligo)saccharide length. Therefore, band fluorescence intensity is directly related to the relative abundance of individual (oligo)saccharide moieties in heterogeneous sample. In the same time, it also indicates that FACE can be used to investigate the interactions of carbohydrates and proteins.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Oligossacarídeos/análise , Oligossacarídeos/química , Proteínas/química , Concanavalina A/química , Corantes Fluorescentes , Hidrólise , Naftalenos
8.
J Enzyme Inhib Med Chem ; 21(5): 597-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17194033

RESUMO

A new compound 2, possessing a tetra-N-acetyl-chitotetraosyl moiety as a constituent, was synthesized by bacterial fermentation, which used allosamizoline 1 as the initial acceptor. A 2-binding chitinase assay, indicated that the chitinase was inactivated by 2 with IC50 = 0.03 microg/mL.


Assuntos
Fermentação , Glucosamina/análogos & derivados , Configuração de Carboidratos , Quitinases/antagonistas & inibidores , Quitinases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Glucosamina/biossíntese , Glucosamina/química , Glucosamina/farmacologia , Ligação Proteica
9.
Artigo em Inglês | MEDLINE | ID: mdl-17111134

RESUMO

We introduced a strategy for preparing a carbohydrate microarray and demonstrated its utility for characterizing carbohydrate binding and activities. We isolated the lipopolysaccharide (LPS) components from different bacteria and explored the possibility of immobilizing these glycoconjugates on a high-binding polystyrene plate. Carbohydrate-specific combination was examined by observing the binding of the blood group B analogic LPS O-polysaccharide from Escherichia coli on the high-binding polystyrene plate and anti-B from a broad spectra antibody of human blood serum. Strong binding of antibodies was screened, as it was evident that relative response value is two times higher than control. The hybridization results indicated that this method is a reliable technique for the detection of human intestinal bacteria and is expected to be applied in diagnostics and seroepidemiology.

10.
Biosci Biotechnol Biochem ; 70(9): 2303-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16960363

RESUMO

UDP-galactose 4-epimerase (EC 5.1.3.2, Gal E) from Escherichia coli catalyzes the reversible reaction between UDP-galactose and UDP-glucose. In this study, the Gal E gene from E. coli, coding UDP-galactose 4-epimerase, was cloned into pYD1 plasmid and then transformed into Saccharomyces cerevisiae EBY100 for expression of Gal E on the cell surface. Enzyme activity analyses with EBY100 cells showed that the enzyme displayed on the yeast cell surface was very active in the conversion between UDP-Glc and UDP-Gal. It took about 3 min to reach equilibrium from UDP-galactose to UDP-glucose.


Assuntos
Enzimas Imobilizadas/metabolismo , Escherichia coli/enzimologia , Saccharomyces cerevisiae/enzimologia , UDPglucose 4-Epimerase/metabolismo , Clonagem Molecular , DNA Bacteriano/química , DNA Bacteriano/genética , Eletroforese Capilar , Enzimas Imobilizadas/genética , Escherichia coli/genética , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/genética , UDPglucose 4-Epimerase/genética , Uridina Difosfato Galactose/metabolismo , Uridina Difosfato Glucose/metabolismo
11.
J Biosci ; 31(2): 219-22, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16809854

RESUMO

A sensitive,specific, and rapid method for the detection of carbohydrate-protein interactions is demonstrated by fluorophore-assisted carbohydrate electrophoresis (FACE). The procedure is simple and the cost is low. The advantage of this method is that carbohydrate-protein interactions can be easily displayed by FACE, and the carbohydrates do not need to be purified.


Assuntos
Carboidratos , Eletroforese/métodos , Corantes Fluorescentes/metabolismo , Naftalenos/metabolismo , Proteínas/metabolismo , Eletroforese/economia , Eletroforese/instrumentação , Sensibilidade e Especificidade
12.
Appl Biochem Biotechnol ; 133(3): 211-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16720902

RESUMO

The work presented herein is a new noncovalent glycoarray assembly method for microplates created by simply mixing together a carbohydrate and a tetradecylamine. alpha-D-Mannopyranoside, alpha-D-glucopyranoside, and alpha-D-galactopyranoside were utilized in model studies and product formations were detected by lectin binding. The method can be extended to study the steric hindrance effect of carbohydrate-protein interactions, namely the structure-function relations of carbohydrates.


Assuntos
Carboidratos/química , Glicolipídeos/química , Aminas/química , Sítios de Ligação , Concanavalina A/química , Concanavalina A/metabolismo , Fluoresceína-5-Isotiocianato/química , Galactose/química , Glucosídeos/química , Glicolipídeos/metabolismo , Lectinas/química , Lectinas/metabolismo , Manose/química , Microscopia de Fluorescência , Modelos Químicos , Proteínas/química , Proteínas/metabolismo , Relação Estrutura-Atividade
13.
Bioorg Med Chem Lett ; 16(11): 2860-1, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16563754

RESUMO

A new compound 7, possessing a tetra-N-acetyl-chitotetraosyl moiety as a constituent, was synthesized by bacterial fermentation which used allosamizoline 6 as the initial acceptor.


Assuntos
Acetilcolinesterase/metabolismo , Proteínas de Bactérias/metabolismo , Glucosamina/análogos & derivados , N-Acetilglucosaminiltransferases/metabolismo , Animais , Electrophorus , Glucosamina/síntese química , Glucosamina/química , Glucosamina/metabolismo , Estrutura Molecular
14.
Bioorg Med Chem Lett ; 16(7): 2031-3, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16427278

RESUMO

The work presented herein is a new noncovalent glycoarray assembly method for microplates created by simply mixing together a carbohydrate and a tetradecylamine. Alpha-mannose was utilized in the model study and product formation was detected by lectin binding. The method can be further extended to array complex carbohydrates.


Assuntos
Glicolipídeos/química , Sequência de Carboidratos , Concanavalina A , Fluoresceína-5-Isotiocianato , Humanos , Imunoglobulina M/sangue , Dados de Sequência Molecular
15.
Bioorg Med Chem Lett ; 16(7): 2042-3, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16403625

RESUMO

Cell density cultivation of recombinant Escherichia coli strains harboring the nodC gene (encoding chitooligosaccharide synthase) from Azorhizobium caulinodans has been previously described as a practical method for the preparation of gram-scale quantities of penta-N-acetyl-chitopentaose. We have now extended this method to the production of allylated derivative of penta-N-acetyl-chitopentaose by using allyl 2-acetamido-2-deoxy-beta-d-glucopyranoside (2) as the initial acceptor for the synthesis of target pentaoside in vivo.


Assuntos
Quitina/síntese química , Ligases/metabolismo , Sequência de Carboidratos , Quitina/análogos & derivados , Escherichia coli/genética , Ligases/genética , Dados de Sequência Molecular
16.
Bioorg Med Chem ; 14(7): 2446-9, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16321537

RESUMO

N-acetyl glucosamine 1 is selectively converted into 2 without protection of the other hydroxyl groups by allylation of the anomeric alkoxide in N,N-dimethylformamide containing lithium bromide. We use cell density cultures to produce the allylated derivative of penta-N-acetyl-chitopentaose by using 2 as the initial acceptor for the synthesis of 3 in vivo. Upon periodate oxidation, 3 is transferred to 4. Compound 4 is quickly subjected to sodium borohydride reduction and NH3 amination, which afforded the target compound 5. In 5-binding chitinase assay, it indicates that the chitinase is obviously inactivated by 5 with IC50 = 4.7 micromol/L.


Assuntos
Quitinases/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Glucosídeos/síntese química , Glucosídeos/farmacologia , Glicosídeos/síntese química , Glicosídeos/farmacologia , Oligossacarídeos/síntese química , Oligossacarídeos/farmacologia , Configuração de Carboidratos , Sequência de Carboidratos , Células Cultivadas , Inibidores Enzimáticos/química , Glucosídeos/química , Glicosídeos/química , Dados de Sequência Molecular , Oligossacarídeos/química , Relação Estrutura-Atividade
17.
Biotechnol Appl Biochem ; 42(Pt 3): 219-22, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15877544

RESUMO

Fluorophore-assisted carbohydrate electrophoresis (FACE) is a straightforward, sensitive method for determining the presence and relative abundance of individual (oligo)saccharides in a(n) (oligo)saccharide mixture. The single-terminal aldehydes of oligoglucoside residues released by acid hydrolysis of beta-1,3-D-glucan from yeast were tagged with the charged fluorophore ANTS (8-aminonaphthalene-1,3,6-trisulphonate), and separated with high resolution on the basis of size by PAGE. ANTS fluorescence labelling was not biased by oligoglucoside length; therefore band fluorescence intensity was directly related to the relative abundance of individual oligoglucoside moieties in a heterogeneous sample. FACE analysis revealed that the major oligoglucoside mixture released by acid hydrolysis from beta-1,3-D-glucan was composed of monosaccharide, disaccharide, trisaccharide, tetrasaccharide, pentasaccharide, hexasaccharide, heptasaccharide and octasaccharide, and the order of abundance from high to low was trisaccharide, monosaccharide, disaccharide, tetrasaccharide, pentasaccharide, hexasaccharide, heptasaccharide and octasaccharide respectively. In conclusion, FACE represents an accessible, sensitive and quantitative analytical tool enabling the characterization of a(n) (oligo)saccharide mixture.


Assuntos
Glucanos/análise , Saccharomyces cerevisiae/química , Sequência de Carboidratos , Eletroforese em Gel de Poliacrilamida , Corantes Fluorescentes , Glucanos/química , Hidrólise , Naftalenos
18.
Bioorg Med Chem ; 13(12): 3873-7, 2005 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-15911303

RESUMO

The epoxyalkyl (1-->3)-beta-D-pentaglucosides 2 and 3 were synthesized in order by acetylation, glycosidation, oxidation, and deacetylation of 1. The immunological activities (superoxide anion production activity, phagocytic activity, and lymphocyte proliferation) and scavenging ability toward superoxide anion of (1-->3)-beta-D-pentaglucoside (1) and its epoxyalkyl derivatives (2 and 3) were investigated. Superoxide anion released from human blood monocytes was measured by the reduction of ferricytochrome c. Phagocytosis by peritoneal macrophages was detected through a teal ingesting that measured the chicken red blood cells (CRBC). Lymphocyte proliferation was determined by the MTT method. The scavenging ability of 1, 2, and 3 toward superoxide anions was evaluated by means of chemiluminescence (CL). The results showed that 2 and 3 had a little higher immunological activity and scavenging ability toward superoxide anion than 1, which indicated that the reducing end of the oligoglucosides was quite important for maximum biological activity.


Assuntos
Glucosídeos/síntese química , Macrófagos Peritoneais/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Oligossacarídeos/síntese química , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Galinhas , Glucosídeos/imunologia , Humanos , Ativação Linfocitária/efeitos dos fármacos , Monócitos/imunologia , Oligossacarídeos/imunologia , Oligossacarídeos/farmacologia , Fagocitose/efeitos dos fármacos , Relação Estrutura-Atividade , Superóxidos/metabolismo
19.
Anal Biochem ; 340(1): 52-6, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15802129

RESUMO

A sensitive, specific, and rapid method for the detection of carbohydrate-protein interactions was demonstrated using quantum dots (QDs) as a fluorescence label coupled with protein. 1,3-Dipolar cycloaddition between azide and alkyne was exploited to attach alpha-d-glucopyranoside to a C(14) hydrocarbon chain that noncovalently binds to the microtiter well surface, and the product formation was detected by both electrospray ionization-mass spectrometry (ESI-MS) and QD- (or fluorescein isothiocyanate (FITC))-conjugated lectin binding. It indicated that the peak intensity of the fluorescence emission was proportional to the initial concanavalin A (Con A) concentration in the range of 2 x 10(-3) micromol/L to 2 x 10(-2)mmol/L with a detection limit at least 100 times lower than that of the FITC-based method.


Assuntos
Metabolismo dos Carboidratos , Análise em Microsséries/métodos , Pontos Quânticos , Coloração e Rotulagem/métodos , Adsorção , Carboidratos/química , Concanavalina A/química , Concanavalina A/metabolismo , Fluoresceína-5-Isotiocianato , Fluorescência , Análise em Microsséries/instrumentação , Estrutura Molecular , Ligação Proteica , Espectrometria de Massas por Ionização por Electrospray
20.
Carbohydr Res ; 340(4): 603-8, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15721330

RESUMO

The title pentasaccharide was synthesized via a 2+3 strategy. The disaccharide donor, 3-O-acetyl-2-O-benzoyl-4,6-O-benzylidene-beta-D-glucopyranosyl-(1-->3)-2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranosyl trichloroacetimidate (8), was obtained by selective coupling of allyl 2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranoside with 3-O-acetyl-2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranosyl trichloroacetimidate (4), followed by deallylation, and trichloroacetimidation. Meanwhile, the trisaccharide acceptor, allyl 2-O-benzoyl-4,6-O-benzylidene-beta-D-glucopyranosyl-(1-->3)-2-O-benzoyl-4,6-O-benzylidene-beta-D-glucopyranosyl-(1-->3)-2-O-benzoyl-4,6-O-benzylidene-beta-D-glucopyranoside (12), was prepared by coupling of allyl 2-O-benzoyl-4,6-O-benzylidene-beta-D-glucopyranosyl-(1-->3)-2-O-benzoyl-4,6-O-benzylidene-beta-D-glucopyranoside with 4, followed by deacetylation. Condensation of 8 with 12, followed by epoxidation, and deprotection, gave the target pentaoside.


Assuntos
Glucosídeos/síntese química , Oligossacarídeos/síntese química , Configuração de Carboidratos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estrutura Molecular , Oligossacarídeos/química , Oxirredução
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