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Use of detergents in the preparation of Salmonella samples for enzyme immunoassay on polymyxin-coated polyester cloth.

Heating Salmonella cells in the presence of detergents such as deoxycholate or Triton x-100 greatly increased the sensitivity of an enzyme immunoassay for lipopolysaccharide antigens using polymyxin-coated polyester cloth as the solid phase for antigen capture. The presence of a 100-fold excess of E. coli lipopolysaccharide in the test sample did not affect the detection of the Salmonella lipopolysaccharide. The sensitivity of the assay using deoxycholate-heat treatment of the antigens followed by detection on polymyxin-coated cloth was equivalent to that of an assay using antibody-coated polyester cloth for antigen capture.

Deoxycholic Acid

An investigation of occlusive polyester surgical clothing.

The bacterial dispersion rate of people wearing operating room clothing made from several types of polyester fabric was compared to conventional cotton clothing, total-body exhaust gowns and disposable clothing. Airborne bacteria were measured in a chamber, three ultra-clean air operating rooms and a conventionally ventilated operating room. The polyester clothing was demonstrated to be much superior to conventional cotton clothing and at least as good as the total-body exhaust gowns and disposable clothing.

Air Microbiology

Thermal degradation of polyester coating powders: 1,4-dicyanobenzene as an occupational marker compound.

A method for the determination of emissions in workroom air as a result of the thermal degradation of polyester coating powders is described. The method is based on the determination of certain marker compounds only. Polyester coating powders were degraded thermally in laboratory experiments and 1,4-dicyanobenzene was chosen as the marker compound. An air sampling method and a high-performance liquid chromatographic method for the determination of the marker compound are proposed. The detection limit for a 48-I air sample was 0.4 microgram m-3.

Air Pollutants, Occupational

Filtration characteristics of the polyester fiber micropore blood transfusion filter.

The filtration characteristics of a new polyester fiber (Fenwal II) micropore blood transfusion filter were investigated. Filtration of stored human whole blood and packed cells resulted in return of screen filtration pressure (SFP) of the blood to normal. Increased filter weights verified removal of large amounts of debris and microaggregates from the blood. Filtration of large quantities of blood accomplished at very high flow rates did not adversely affect the composition of the filtered blood. We conclude that the polyester fiber (Fenwal II) micropore blood transfusion filter is effective in removing microaggregates from stored whole blood and packed cells. It has a high volume capacity, allows rapid flow, and is reliable during pressure transfusion.

Blood Banks

In vivo evaluation of polyester arterial grafts coated with albumin: the role and importance of cross-linking agents.

Previous in vitro studies have predicted that the type of chemical used to cross-link albumin-coated polyester arterial prostheses may influence the rate of bioerosion of the albumin layer in vivo. This study has confirmed that the healing process of this type of compound prosthesis does indeed depend on the nature and concentration of the cross-linking agent used. Four series of implantations in the thoracic aorta of dogs for scheduled periods for 4 h up to 6 months were conducted using 1.6% glutaraldehyde, 2.5% glutaraldehyde and 0.2 M carbodiimide as the alternative cross-linking agents plus a nonalbuminated preclotted polyester prosthesis which served as the control. The pathology of the explanted grafts revealed that in the short and medium term the rate of healing and the extent of tissue ingrowth was dependent initially on the presence of and later on the rate of bioerosion of the albumin layer. After 3 months in situ, the prostheses coated with albumin cross-linked with 1.6% glutaraldehyde and carbodiimide had healed more rapidly and were invaded by more extensive tissue ingrowth than the one cross-linked with 2.5% glutaraldehyde or the preclotted control. Moreover, the migration of cells over the carbodiimide-treated surface was the most fully developed and most regularly organized of all four series. Immunostaining revealed that the presence of glutaraldehyde induced an inflammatory response which failed to support the growth of normal luminal cells with the endothelial phenotype.

Aldehydes

Acid ethanol fixation and polyester wax embedding combines preservation of antigenic determinants with good morphology and enables simultaneous bromodeoxyuridine (BrdU) labeling.

Lymphoid tissue, and/or isolated peripheral mononuclear blood cells were fixed in acid ethanol and embedded in polyester wax (melting point 37 C). The excellent cytomorphology obtained allowed distinguishing different types of individual lymphoid and nonlymphoid cells. Furthermore, this procedure was satisfactory in the immunophenotyping of histiocytes, endothelial, mesenchymal, epithelial cells, different (sub-) types of lymphocytes and also of lymphokine activated killer (LAK) cells. The staining patterns obtained with the different poly- and monoclonal antibodies on polyester wax sections were not only analogous to those obtained on frozen sections, but cells which had incorporated bromodeoxyuridine could be double labeled with specific antiserum.

Bromodeoxyuridine

Albumin-coated polyester arterial prostheses: is xenogenic albumin safe?

This paper adds a new dimension to the series of studies concerned with the development of an albumin-coated polyester vascular prosthesis by addressing the question of the origin of the albumin. Previous experiments in dogs have used canine albumin-coated polyester arterial grafts. This study evaluated the biocompatibility of xenogenic material by implanting in dogs prostheses coated with bovine albumin and cross-linked with glutaraldehyde. Two series of albuminated grafts, one gamma radiation sterilized, the other ethylene oxide sterilized, as well as a preclotted control series were undertaken. The origin of the albumin did not appear to be significant. In fact, the healing pattern of the xenogenic albumin coated grafts was identical to that found previously with isogenic albumin. Nor did the method of sterilization produce significantly different pathological results. However, a slower rate of healing with the coated grafts compared to the preclotted controls did appear to be related to the slow rate of albumin erosion and the potentially cytotoxic effect of the glutaraldehyde cross-linking agent.

Albumins

Carbon and polyester fibers as a scaffold for bone repair. Studies of segmentary implants in the rabbit radius.

To determine the function in the repair of bone defects, implants of carbon and polyester fibers of comparable dimensions were used to replace a 2-cm long segment of the radius of 29 rabbits. The healing process was analyzed by scintigraphic, radiographic, and histologic methods after periods of 15-90 days, comparing the results with a control group without implants. In the rabbit, carbon and polyester fibers did not induce repair of bone defects, although they did permit invasion of the implant during the later stages.

Animals

[Evaluation of long term results of treating patellar fractures with polyester sutures].

The late results of patellar fractures treatment with polyester suture in 24 patients with an average follow up of 8.1 year was presented. The method proved to be useful in transverse fractures of the central and distal part od the patella as well as in multi-fragmented ones. The evaluation of patello-femoral arthritic changes has remarkably influenced the overall clinical result. The displacement of 2 mm or more within articular surface existing postoperatively implicates bad prognosis, polyester suture is mechanically strong and requires no additional operation to remove the material used for fixation.

Adult

[Sternotomy wound closure with polyester tapes].

We developed the special polyester tape with Tetron coating for sternal closure. Fifty consecutive open heart cases had the sternum closed with the tapes in the past six months at Nippon Medical School Hospital. There was no sternal infection or mediastinitis postoperatively. The tape closure method was more effective in approximation of sternum than the ordinary wire closure, especially in the case with fragile sternum. Although a long term follow-up is necessary, the result of sternal closure with the polyester tape has been satisfactory.

Humans

[Interference of inflammation caused by polyester with the growth of Yoshida ascite hepatoma. IV. Modifications of the sedimentation profile of the hepatoma cells].

It was previously shown that Yoshida's ascites-hepatoma cells (Y cells) intraperitoneally injected into rats carrying chronic inflammation caused by polyester thread rapidly disappear. In this paper the sedimentation rate in a continuous Percoll gradient at unit gravity (1 g) using the CELSEP apparatus (Sorvall), the mean diameter and volume of the Y cells harvested from the peritoneal cavity of untreated (NT) and polyester-treated (TM) animals were determined at 6-12-18-24 hours after the inoculum. At 6 hours a number of Y cells appeared enlarged both from TM and NT rats, while afterwards, and notably at 18 and 24 hours, their size was decreased and their sedimentation rate was reduced only in TM animals. It seems that the chronic inflammation causes alterations both in the size and in the density of the Y cells and probably one of the mechanisms of their death is through shrinkage and apoptosis.

Animals

Polyester film as an advantageous tool for light and ultrastructural examination of single cells infected with viruses.

The use of marked transparent polyester film as a support of cell monolayer, smears or sections (cryostat or paraffin), makes possible to examine the same cell preselected in the light microscope by electron microscope (EM). Consequently, this technique enables to use histological or immunohistological investigations (using immunofluorescence or peroxidase (Px) labelling) by light microscopy before examination in EM. As example we used herpes simplex virus (HSV) type 1-infected cells grown on the above mentioned polyester film. Visualization of the antigen with hyperimmune serum and Px-labelled antiserum was followed by examination of selected cells in EM, where viral particles were clearly visible.

Cells, Cultured

[Treatment of female urinary stress incontinence with a Zoedler suspension-plasty and a new, stable, radiopaque polyester sling].

We report on 183 patients with urinary stress incontinence treated with bladder-neck suspension plasty according to Zoedler from 1972-1982 using the conventional nylon sling. 86.1% of the patients were continent postoperatively. Long term follow-up to 10 years however showed a continuous decrease of success rate in the first 2 postoperative years (74.9% in the 1st, 67.2% in the 2nd year). From the 3rd postoperative year there was a stable continence-rate of 50.7%. As the significant increase of incontinence relapse is due to enzymatic destruction of the nylon sling--first described in ophtalmology--we developed a new form-stable and radiopaque polyester sling. Since 1983 we implanted this new sling in 40 patients. Long term results of the conventional Zoedler procedure and first results of a modified method using the new polyester sling are discussed.

Female

[Progressive complications associated with polyester arterial prostheses. Study of 61 specimens following surgical excision].

Reports of individual surgical cases tend to be anecdotal because of the unique circumstances surrounding the patient, the surgeon, the intervention and, where applicable, the prosthetic device. To overcome this limitation the authors have taken a wider collaborative approach and report the analysis of 61 explanted polyester arterial prostheses associated with delayed complications on 53 patients reoperated upon in six different French hospitals. One advantage of such an independent and centralized retrieval programme is that the impact of centre specific factors, such as patient selection and surgical techniques, is minimized. Consequently, by following a standardized protocol for the evaluation of the morphologic, pathologic and mineralogic characteristics of the tissue surrounding the excised grafts, as well as the textile structure of the prostheses themselves, it has been possible to distinguish between iatrogenic and disease related complications and to demonstrate a number of general findings associated with the clinical performance of polyester arterial prostheses. Complications such as thromboses, infections and false aneurysms appear to occur randomly after different lengths of implantation, thicker fibrous tissue capsules are associated with velour grafts with highly textured yarns, the incidence of mineralized tissue and of endothelialized luminal surfaces is rare, weft knitted textile prostheses appear less mechanically stable and more sensitive to iatrogenic trauma than warp knitted, and the incidences of lipid and cholesterol adsorption, bacterial colonization and sterile fluid loss need further investigation. These observations lead to the recommendation that for patients with longer life expectancies surgeons should consider selecting low porosity, woven or warped knitted prostheses which contain yarns that have not been highly textured.

Adult

Airway responsiveness in workers processing polyester resins.

In 22 employees of a button-manufacturing plant, exposure to polyester resins over an eight-hour work shift resulted in an acute reduction of flow rates on maximum expiratory flow volume (MEFV) curves at MEF50% and MEF25%. In the workers studied, preshift administration of 80 mg of propranolol potentiated, while 1 mg of subcutaneously injected atropine significantly inhibited, the bronchoconstricting effect of the resins, indicating that the autonomic nervous system plays an important role in determining airway smooth muscle response to polyester resins. Although a high prevalence of acute symptoms (cough, shortness of breath, throat and eye irritation) over the work shift was recorded in exposed workers, no high prevalence of chronic respiratory symptoms was found. No definite evidence of chronic airway obstruction was recorded in exposed workers.

Adult

The cytocompatibility of compound polyester-protein surfaces using an in vitro technique.

To avoid the need to preclot porous polyester (Dacron) vascular prostheses, we have proposed the use of a protein coating that will promote the growth and adhesion of endothelial cells. This study assessed the relative advantages of coating woven, knitted, and velour polyester fabrics with albumin, collagen, and a albumin-collagen mixture after preservation in saline or drying by a commercial dehydration process. Preclotted fabrics were used as controls. The cytocompatibility of these biopolymers was measured by an organotypic culture technique which relies on the migration of chick embryonic endothelial cells. After 7 d of culture the cytocompatibility was quantified by counting the cells in the area of migration and the morphology of the endothelial cells was observed by scanning electron microscopy. In general, the knitted and velour fabrics showed superior compatibility than the woven one. The results confirmed that collagen, either alone or combined with albumin, provides in most cases a more cytocompatible surface than albumin alone. A cell morphology most closely resembling that of natural arterial endothelial cells was observed on the albumin-collagen substrate.

Albumins

Radiosterilization of albuminated polyester prostheses.

The study reported here is concerned with the radio-sterilization of Dacron vascular prostheses coated with crosslinked albumin. gamma-Radiations have no effect on the mechanical properties of the polyester fibres or on their crystallinity, whether irradiated in a dry state or immersed in saline. Special attention has been paid to the release of the albumin, or protein fragments from the reticulum using 125I-labelled albumin as a radiotracer. The albumin leakage depends upon the type of Dacron fabrics considered but the values derived from radioactivity measurements are always greater than those directly measured, which indicates a radio-induced break of the bond between iodine and albumin; this has nothing to do with the break of the association between albumin and Dacron. Moreover no cytotoxicity of the irradiated immersion medium has been observed using a test based on organotypic culture in liquid medium. Thus radio-sterilization of an albuminated polyester vascular prosthesis immersed in saline appears to be a suitable procedure.

Albumins