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1.
J Foot Ankle Surg ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38972566

ABSTRACT

It has been demonstrated in a number of studies that high levels of uric acid can cause crystal deposition in the tendons of the lower extremities, which in turn can impair the Achilles tendon. This study aimed to interpret whether hyperuricemia is relevant with Achilles tendon rupture. Patients diagnosed with Achilles tendon rupture at the same institution between 2013 and 2022 were included in the case group. Healthy subjects who had physical examinations during the same period were included in the control group. Propensity score matching was used to match in a 1:1 ratio. Demographic and clinical characteristics of patients in both groups were compared. Five hundred and fourteen patients were included in the study (ATR=257; Control group=257). The proportion of individuals with hyperuricemia varied significantly between the two groups (Achilles tendon rupture group=43.6%; control group=27.6%; p<0.001). The Achilles tendon rupture and hyperuricemia were linked by conditional logistic regression (p<0.001; OR=2.036; 95CI%=1.400-2.961). Compared with healthy subjects, patients with hyperuricemia have a higher risk of Achilles tendon rupture. Further studies are required to verify the effects of hyperuricemia and monosodium urate crystals on Achilles tendon structure.

2.
IEEE Trans Vis Comput Graph ; 29(12): 5556-5568, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36367917

ABSTRACT

3D scene graph generation (SGG) has been of high interest in computer vision. Although the accuracy of 3D SGG on coarse classification and single relation label has been gradually improved, the performance of existing works is still far from being perfect for fine-grained and multi-label situations. In this article, we propose a framework fully exploring contextual information for the 3D SGG task, which attempts to satisfy the requirements of fine-grained entity class, multiple relation labels, and high accuracy simultaneously. Our proposed approach is composed of a Graph Feature Extraction module and a Graph Contextual Reasoning module, achieving appropriate information-redundancy feature extraction, structured organization, and hierarchical inferring. Our approach achieves superior or competitive performance over previous methods on the 3DSSG dataset, especially on the relationship prediction sub-task.

3.
Enzyme Microb Technol ; 48(6-7): 454-7, 2011 May 06.
Article in English | MEDLINE | ID: mdl-22113016

ABSTRACT

The influence of reaction media on the racemic temperature (T(r)) in the lipase-catalyzed resolution of ketoprofen vinyl ester was investigated. An effective approach to the control of the enzymatic enantioselectivity and the prediction of the increasing tendency was developed based on the T(r) influenced by reaction media. The T(r) for the resolution catalyzed by Candida rugosa lipase (CRL) was found at 29 °C in aqueous and S-ketoprofen was obtained predominantly at 40 °C. However, CRL showed R-selectivity at 40 °C in diisopropyl ether because the T(r) was changed to 56 °C. CRL, lipase from AYS Amano(®) and Mucor javanicus lipase were further applied for the investigation of the enzymatic enantioselectivity in dioxane, DIPE, isooctane and their mixed media with water. The effects of the reaction medium on T(r) could be related to the solvent hydrophobicity, the lipase conformational flexibility and the interaction between the enantiomers and the lipase.


Subject(s)
Fungal Proteins/metabolism , Lipase/metabolism , Stereoisomerism , Temperature , Biocatalysis , Candida/enzymology , Hydrolysis , Hydrophobic and Hydrophilic Interactions , Indicators and Reagents , Ketoprofen/analogs & derivatives , Ketoprofen/metabolism , Molecular Conformation , Mucor/enzymology , Octanes , Protein Conformation , Solvents , Water
4.
J Biotechnol ; 153(3-4): 111-5, 2011 May 20.
Article in English | MEDLINE | ID: mdl-21419813

ABSTRACT

This paper reported the modulation of enzyme activity by organic small molecule. The esterification activity of Penicillin G acylase (PGA) was improved more than 70-fold by the addition of 10% N-methylimidazole. Some control experiments have been designed to demonstrate the catalytic specificity of PGA. The structure and the amount of additive were optimized to improve the product yield. The influence of N-methylimidazole on the PGA conformation was investigated by FTIR and autodock simulation. Seven substrates were used to evaluate the effect of structure on the PGA-catalyzed transesterification. A series of products were successfully synthesized with the yield ranged from 56% to 84% and PGA showed specific recognition on the substrate with phenyl group in the presence of 10% N-methylimidazole.


Subject(s)
Enzymes, Immobilized/chemistry , Imidazoles/pharmacology , Penicillin Amidase/chemistry , Vinyl Compounds/chemistry , Acylation , Bioengineering , Enzymes, Immobilized/metabolism , Esterification , Guaifenesin/analogs & derivatives , Guaifenesin/chemistry , Guaifenesin/metabolism , Imidazoles/chemistry , Ligases/chemistry , Ligases/metabolism , Models, Molecular , Penicillin Amidase/metabolism , Spectrophotometry, Infrared , Substrate Specificity , Vinyl Compounds/metabolism
5.
J Biotechnol ; 145(3): 240-3, 2010 Feb 01.
Article in English | MEDLINE | ID: mdl-19963019

ABSTRACT

Nitroalkanes underwent fast additions to a variety of structurally diverse aldehydes under the catalysis of d-aminoacylase in DMSO. The influences of reaction conditions including solvents, temperature, enzyme concentration and molar ratio of substrates were systematically investigated. Seventeen products were obtained in short time with moderate to high yields. It is the first report on hydrolase-catalyzed fast Henry reaction in organic solvent.


Subject(s)
Aldehydes/metabolism , Alkanes/metabolism , Biocatalysis , Hydrolases/metabolism , Models, Chemical , Nitro Compounds/metabolism , Solvents/metabolism , Benzaldehydes/chemistry , Benzaldehydes/metabolism , Ethane/analogs & derivatives , Ethane/chemistry , Ethane/metabolism , Nitroparaffins/chemistry , Nitroparaffins/metabolism , Substrate Specificity
6.
Bioorg Med Chem ; 16(9): 5181-8, 2008 May 01.
Article in English | MEDLINE | ID: mdl-18358726

ABSTRACT

We established a facile regioselectively chemo-enzymatic synthesis procedure for the preparation of mutual derivatives of nucleosides and pyrimidines by sequential Markovnikov addition and acylation. Firstly, pyrimidine derivatives containing vinyl ester group were synthesized from pyrimidines and divinyl esters through Markovnikov addition catalyzed by K(2)CO(3) in DMSO at 80 degrees C, and the yields were ranged from 50% to 87%. Then regioselective acylation of ribavirin and cytarabine with pyrimidine vinyl ester was catalyzed by CAL-B (immobilized lipase from Candida antarctica) in anhydrous acetone. Reaction conditions of enzymatic acylation including enzyme resource and solvents were optimized. A series of mutual derivatives of nucleosides and pyrimidines were synthesized successfully and characterized with NMR, IR, and HRMS. This chemo-enzymatic protocol involving sequential Markovnikov addition and acylation provided a novel way of synthesizing complicated functional compounds regioselectively which was hard to be achieved either by chemical or by enzymatic methods.


Subject(s)
Enzymes, Immobilized/chemistry , Lipase/chemistry , Nucleosides/chemical synthesis , Pyrimidines/chemical synthesis , Acylation , Candida/enzymology , Carbonates/chemistry , Catalysis , Cytarabine/chemical synthesis , Cytarabine/chemistry , Fungal Proteins , Molecular Structure , Nucleosides/chemistry , Potassium/chemistry , Pyrimidines/chemistry , Ribavirin/chemical synthesis , Ribavirin/chemistry , Stereoisomerism
7.
Chem Commun (Camb) ; (20): 2078-80, 2007 May 28.
Article in English | MEDLINE | ID: mdl-17713084

ABSTRACT

A zinc-dependent acylase, D-aminoacylase from Escherichia. Coli, displays a promiscuous activity to catalyze the carbon-carbon bond formation reaction of 1,3-dicarbonyl compounds to methyl vinyl ketone in organic media.


Subject(s)
Amidohydrolases/metabolism , Carbon/chemistry , Carbon/metabolism , Organic Chemicals , Zinc/metabolism , Binding Sites , Catalysis , Cations, Divalent/chemistry , Escherichia coli/enzymology , Methylation , Molecular Structure , Solvents , Zinc/chemistry
8.
Chem Commun (Camb) ; (3): 295-7, 2007 Jan 21.
Article in English | MEDLINE | ID: mdl-17299644

ABSTRACT

N-methylimidazole, a molecular solvent, but also, in cationic form, a component of 1-alkyl-3-methylimidazolium ([C(n)MIM]+) ionic liquids, showed promise as an additive in accelerating remarkably transesterification catalyzed by lipase acrylic resin from Candida antarctica (CAL-B).


Subject(s)
Imidazoles/pharmacology , Lipase/metabolism , Ribavirin/chemistry , Ribavirin/metabolism , Acylation/drug effects , Anions/chemistry , Candida/enzymology , Catalysis/drug effects , Ionic Liquids , Molecular Structure
9.
J Org Chem ; 71(10): 3991-3, 2006 May 12.
Article in English | MEDLINE | ID: mdl-16674082

ABSTRACT

A basic ionic liquid, 1-methyl-3-butylimidazolium hydroxide ([bmIm]OH), has been introduced as a catalyst and reaction medium for the Markovnikov addition of N-heterocycles to vinyl esters under mild conditions. The evidence for the role of this basic ionic liquid [bmIm]OH in promoting the Markovnikov addition has been given. On the basis of the evidence, a mechanism was postulated.

10.
Biotechnol Lett ; 27(10): 717-20, 2005 May.
Article in English | MEDLINE | ID: mdl-16049740

ABSTRACT

Lipase-catalyzed synthesis of potential multifunctional ribavirin derivatives was performed in acetone. Divinyl dicarboxylates with different chain lengths (C4, C6, C9, C10) were used as acyl donors and the reactions were catalyzed by lipase immobilized on acrylic resin from Candida antarctica (CAL-B). Ribavirin was regioselectivly acylated at the primary hydroxyl groups and the corresponding vinyl esters (C4, C6, C9, C10) were prepared in respective yields of 48%, 65%, 54%, 55%.


Subject(s)
Candida/enzymology , Lipase/metabolism , Ribavirin/metabolism , Acetone/chemistry , Acylation , Alkenes/chemistry , Alkenes/metabolism , Butadienes/chemistry , Butadienes/metabolism , Chromatography, Thin Layer , Dicarboxylic Acids/chemistry , Dicarboxylic Acids/metabolism , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Lipase/chemistry , Ribavirin/chemistry , Substrate Specificity
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