PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Polyesters”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51Linked to original sources
PubMed1999

Glucose polyester biosynthesis. Purification and characterization of a glucose acyltransferase.

Glandular trichomes of the wild tomato species Lycopersicon pennellii secrete 2,3,4-O-tri-acyl-glucose (-Glc), which contributes to insect resistance. A Glc acyltransferase catalyzes the formation of diacyl-Glc by disproportionating two equivalents of 1-O-acyl-beta-Glc, a high-energy molecule formed by a UDP-Glc dependent reaction. The acyltransferase was purified 4,900-fold from L. pennellii leaves by polyethylene glycol fractionation, diethylaminoethyl chromatography, concanavalin A affinity chromatography, and chromatofocusing. The acyltransferase possesses an isoelectric point of 4.8, a relative molecular mass around 110 kD, and is composed of 34- and 24-kD polypeptides as a heterotetramer. The 34- and 24-kD proteins were partially sequenced. The purified enzyme catalyzes both the disproportionation of 1-O-acyl-beta-Glcs to generate 1,2-di-O-acyl-beta-Glc and anomeric acyl exchange between 1-O-acyl-beta-Glc and Glc.

Acetates↗
PubMed2000

The polyester polyurethanase gene (pueA) from Pseudomonas chlororaphis encodes a lipase.

A gene (pueA, polyurethane esterase A) encoding an extracellular polyurethanase (PueA) was cloned from Pseudomonas chlororaphis into Escherichia coli. The enzyme secreted from E. coli showed esterase activity when assayed with p-nitrophenyl acetate. Subcloning of a 3. 2-kb SalI-EcoRI fragment into a T7 RNA polymerase expression vector (pT7-6) produced a (35)S-labeled protein of 65 kDa. Nucleotide sequencing of pueA showed an open reading frame encoding a 65-kDa protein of 617 amino acid residues, with the serine hydrolase consensus sequence GXSXG. PueA was over-expressed using the pT7-6 vector transformed into E. coli BL21(DE3) and was purified in one step using Sephadex G-75.

Amino Acid Sequence↗
PubMed2006

Reconstruction of the anterior cruciate ligament using the polyester ABC ligament scaffold: a minimum follow-up of four years.

We carried out a prospective study of 71 patients who had undergone reconstruction of the anterior cruciate ligament with the ABC scaffold. Their mean age was 28 years (18 to 50). All had either sub-acute or chronic traumatic deficiency of the ligament. The mean period of follow-up was five years (four to seven). Assessment included the use of the International Knee Documentation Committee score, the modified Lysholm score, the Tegner Activity score, the Knee Injury and Osteoarthritis Outcome score and measurement with the KT-1000 arthrometer. Two patients had mild recurrent synovitis. There were no infections and no failures of the ligament. During the period of study, two patients sustained a traumatic fracture of a femoral condyle. The implants retained their integrity in both cases. All patients returned to their previous or enhanced levels of daily activity by three months after operation and 56 (79%) achieved their pre-injury level of sporting activity by six months. The patients who were competing in National level sports returned to play at one level less after operation than before. The Lysholm score showed that 58% of the patients (41) were excellent, 34% (24) good, and 8% (6) fair, with a mean post-operative score of 93. According to the International Knee Documentation Committee score, 35% of knees (25) were 'normal', 52% (37) 'nearly normal' and 13% (9) 'abnormal'. Complete satisfaction was noted in 90% of patients (64). The development of osteoarthritis and the management of anterior cruciate deficiency associated with laxity of the medial collateral ligament remains uncertain. Our results indicate that in the medium-term, the ABC ligament scaffold is suitable and effective when early and safe return to unrestricted activities is demanded. We acknowledge the current general hostility towards reconstruction of the anterior cruciate ligament with artificial materials following reports of early failure and chronic synovitis associatiated with the production of particulate debris. We did not encounter these problems.

Adolescent↗