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At least 937 records · Page 52Linked to original sources
PubMed1995

Utilization of hydrolyzed sucrose polyester (olestra) in broiler diets.

Three experiments were conducted in which hydrolyzed olestra (HO) and hydrolyzed olestra manufacturing by-product (HBP) were compared with corn oil (CO) and a feed-grade hydrolyzed animal-vegetable fat blend (AVF) as fat supplements in diets for broilers. Various blends of HO and HBP with AVF and other fat sources were also evaluated. Results of these experiments indicate that HO or HBP may be used as energy sources in broiler diets. Use of these materials as the sole source of supplemental fat often reduced body weight gain and impaired feed utilization as compared with CO or AVF; however, when used as a component of a blended fat product typical of industry supplements, there was little if any adverse effect on live performance. Carcass fatty acid content was a reflection of dietary fat content. If the blend of fats containing HO or HBP contains a suitable ratio of unsaturated and saturated fatty acids, the product should be an acceptable source of supplemental energy in broiler diets.

Animal Feed↗
PubMed2000

Enhanced endothelialization and microvessel formation in polyester grafts seeded with CD34(+) bone marrow cells.

The authors have shown accelerated endothelialization on polyethylene terephthalate (PET) grafts preclotted with autologous bone marrow. Bone marrow cells have a subset of early progenitor cells that express the CD34 antigen on their surfaces. A recent in vitro study has shown that CD34(+) cells can differentiate into endothelial cells. The current study was designed to determine whether CD34(+) progenitor cells would enhance vascular graft healing in a canine model. The authors used composite grafts implanted in the dog's descending thoracic aorta (DTA) for 4 weeks. The 8-mm x 12-cm composite grafts had a 4-cm PET graft in the center and 4-cm standard ePTFE grafts at each end. The entire composite was coated with silicone rubber to make it impervious; thus, the PET segment was shielded from perigraft and pannus ingrowth. There were 5 study grafts and 5 control grafts. On the day before surgery, 120 mL bone marrow was aspirated, and CD34(+) cells were enriched using an immunomagnetic bead technique, yielding an average of 11.4 +/- 5. 3 x 10(6). During surgery, these cells were mixed with venous blood and seeded onto the PET segment of composite study grafts; the control grafts were treated with venous blood only. Hematoxylin and eosin, immunocytochemical, and AgNO(3 )staining demonstrated significant increases of surface endothelialization on the seeded grafts (92% +/- 3.4% vs 26.6% +/- 7.6%; P =.0001) with markedly increased microvessels in the neointima, graft wall, and external area compared with controls. In dogs, CD34(+) cell seeding enhances vascular graft endothelialization; this suggests practical therapeutic applications. (Blood. 2000;95:581-585)

Animals↗
PubMed2000

Conversion of solvent evaporation residues from the AB- (acetone - butanol) bioprocess into bacterial cells accumulating thermoplastic polyesters.

In a bioconversion study based on utilisation of by-products from the AB- (acetone - butanol) bioprocess a new isolated gram-negative solvent tolerant bacterium was used to convert the AB process residue after removal of the major part of the solvents. The bacterium identified as a representative of the genus Alcaligenes (designated as Alcaligenes sp. G) was capable of growth up to optical densities ranging from 8 to 20 and simultaneously of polyhydroxyalkanoate-(PHA-)accumulation up to 40% per dry weight. A standardised medium based on AB by-products containing 7 g/l of butyrate and 5 g/l of acetate at pH 7.5 was used in our studies for bioconversion into PHAs. Concentrations of 1-butanol, which is known for its membrane damaging properties in microorganisms, were tolerated in the AB by-products medium up to 4 g/l without significant inhibition of cellular growth. No inhibition of growth was observed, when the medium was adjusted to 40 g/l butyrate. Due to the toxicity of the remaining 1-butanol maintenance of sterility is of no high priority during the process. The use of acetate and butyrate from an AB process is expected to provide a higher return-on-investment than the combustion of biogas to help meet energy demands.

Acetone↗
PubMed2000

[Study on preparation and pharmacodynamics of insulin-loaded polyester microparticles].

AIM: To investigate the possibility of using poly (epsilon-caprolactone-block-D, L-lactide) (PLCA) as a kind of materials to prepare the microparticles drug carrier. METHODS: PCLA-MP (microparticle, MP) was prepared by double-emulsification solvent evaporation method. Its morphology was examined by scanning electron microscope. Its size diameter was examined by particle analyser. Insulin (INS), as a model drug, was then encapsulated into PCLA-MP (INS-PCLA-MP). HPLC method was established for determining INS in INS-PCLA-MP. An "antibody-capture" procedure was devised for investigating encapsulation mechanism. The in vitro release behaviour of INS-PCLA-MP was determined in phosphatic buffer solution (pH 7.4). The diabetic rat model was established and blood glucose levels were measured using glucose oxidase (GOD-PAP) method to evaluate the hypoglycaemic effects after subcutaneous administration of INS-PCLA-MP. The pharmacological bioavailability (PBA) of INS-PCLA-MP was calculated from the area above the curve (AAC) in contrast with INS-solution. RESULTS: The mean diameter of INS-PCLA-MP was 1.9 microns, while the encapsulation ratio of INS reached to 76.46%. Only 18.25% encapsulated INS was on the surface of the microparticles, it could be measured by "antibody-capture" experiment. The in vitro release curve of INS-PCLA-MP consists of initial rapid release stage followed by slower exponential stage. In pharmacodynamic studies, after subcutaneous administration of INS-PCLA-MP 12 u.kg-1, the hypoglycaemic effect was significant. The PBA of INS-PCLA-MP was 123.08%. CONCLUSION: PCLA might become a new drug carrier material in the future.

Animals↗
PubMed1992

[Clinical and tomographic evaluation of polyester prosthesis of the anterior crucial ligament made by TRICOMED in Lodz].

This study involves 38 patients in the age is 24-51 years with the III degree instability of the knee who underwent ACL replacement with PPT artificial ligament, beginning from 1986. For the majority the operation mentioned above was the second or even the third intervention after the previous ones, meniscectomy and suture repair included. In 6 patients, who underwent BJ plastic method, the return of the instability was observed. 24 patients were examined after an average follow up time of 34 months. 1 patient was operated on for the ligament replacement 4 years after the first operation, another one was operated on for synthetic arthritis one year after. Estimation of the results is based on clinical examination, subjective professional opinion and CT. 21 patients showed excellent results, which correspond with CT examination and confirm good quality of PPT ligament.

Adult↗