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At least 541 records · Page 30Linked to original sources
PubMed1984

Permeability of latex and polyvinyl chloride gloves to 20 antineoplastic drugs.

Permeability of latex and polyvinyl chloride (PVC) gloves to 20 injectable antineoplastic drugs was studied. Four types of gloves were evaluated: latex surgical gloves, latex examination gloves, and PVC gloves in two thicknesses. Each glove material was exposed to each drug for 90 minutes, and permeation was tested using a mutagenicity assay. Individual fingertips of thin PVC gloves and latex surgical gloves were tested for permeability at five time points (2-30 minutes) using a doxorubicin coloration assay. All drugs permeated the thin PVC gloves. Latex surgical gloves were definitely permeable to two drugs (carmustine and thiotepa) and exhibited borderline permeability to mechlorethamine hydrochloride. The thick PVC gloves were definitely permeable to four drugs (carmustine, thiotepa, mechlorethamine hydrochloride, and daunorubicin hydrochloride) and exhibited borderline permeability to two drugs (doxorubicin and mercaptopurine). The latex examination gloves were permeable to carmustine, thiotepa, mechlorethamine hydrochloride, and cyclophosphamide. Doxorubicin permeation of individual fingertips of thin PVC gloves varied in time and amount. Doxorubicin did not permeate the latex surgical glove material, but testing with thiotepa showed that individual fingertips of this material also varied in permeability. Glove thickness was a major determinant of permeability; latex surgical gloves were the least permeable and thin PVC gloves the most permeable to the antineoplastic drugs tested. Within individual gloves and glove types, time and amount of permeation were not uniform.

Antineoplastic Agents↗
PubMed1983

[Percutaneous-peripheral vena cava catheterization in intensive care of premature and newborn infants. Comparison of Shaw's silastic catheter with the customary polyvinyl catheter].

Central venous catheters inserted via peripheral veins are commonly used in neonatal intensive care. Handling of two commonly available catheters made of different materials were compared during application in 85 neonates under intensive care. Polyvinylchloride and silicone rubber were used as catheter material. Advantages of silicone rubber catheter were detected especially in very low birth weight premature infants. Successful puncture of the peripheral veins and correct positioning could be performed in a higher proportion of these babies than when using polyvinylchloride-catheters. The insertion of polyvinyl-catheters needs shorter time of manipulation and during infusion we found a significantly lower incidence of mechanical problems with the catheter.

Catheterization↗
PubMed1984

Suppression of the anti-trimellityl (TM) IgE response in mice by conjugates of TM with polyvinyl alcohol.

The i.p. injection of 1 microgram of TM3-OA or TM9-OA with 1 mg of A1(OH)3 into B6D2F1 mice elicited the production of antibodies of the IgE and other classes to the trimellityl (TM) group and ovalbumin (OA). The induction of anti-TM antibodies belonging to the IgE and other immunoglobulin classes was specifically suppressed by the administration of tolerogenic conjugates prepared by coupling trimellitic anhydride (TMA) to the hydrophilic non-immunogenic polymer, polyvinyl alcohol (PVA), prior to immunization with TM-OA conjugates. More importantly, established anti-TM responses were also suppressed by these TM-PVA conjugates. By contrast, however, treatment with TM-PVA conjugates did not affect either the primary or the established anti-OA antibody response. The tolerogenic effects of the PVA conjugates were dose-dependent and appeared also to be dependent on the epitope density. Treatment with these conjugates also prevented immunized mice from showing any symptoms of systemic anaphylaxis on challenge with polyvalent TM-protein conjugates. These findings indicate that these conjugates may have the potential of useful therapeutic agents for the treatment of TMA-induced pulmonary hypersensitivity diseases.

Anaphylaxis↗
PubMed1983

[Transcatheteral embolization with polyvinyl alcohol--technic and experimental studies].

The article presents hardened polyvinyl alcohol foam (PVA) as embolisation material. PVA is well tolerated by the tissue and produces permanent vascular sealing. It is possible to achieve peripheral embolisation of arteries having a diameter of approx. 100 microns, as well as sealing of vessels with diameter of up to 8 mm. Pressed PVA is used for occluding larger vessels. This PVA re-assumes its original shape and dimensions in liquids, depending on their osmolarity and molecular size. Depending upon the pressure exercised, compression and re-expansion can be fourfold to tenfold.

Angiography↗
PubMed1982

[Use of polyvinyl alcohol for preparing frozen histological sections].

The authors developed a new method for preparation of frozen histological sections. It consists in the use of glycerin-plastified polymer, polyvinyl alcohol, and distilled water for impregnation of tissue pieces and subsequent freezing of them in the same medium. This produces histological sections of high quality. The frozen sections are sufficiently thin (3--5 micrometers). The method excludes cell structure destruction by ice crystals and overfreezing of blocks; the sections do not crumble. Losses of free cell elements, extraction of substances and other artifacts are minimized. The frozen histological sections are firmly glued to the glass without using protein with glycerin. The method saves time and reagents for the preparation of the sections and allows their wide use in morphological and histochemical studies.

Animals↗
PubMed1980

Acute glomerular lesions induced by polyvinyl alcohol-bovine serum albumin (PVA-BSA) complex in the rat--a possible mechanism of local immune complex formation.

Two types of renal lesions, renal cortical necrosis and acute proliferative glomerular lesions were induced by a single or several intravenous injections of polyvinyl alcohol (PVA)-bovine serum albumin (BSA) complex in Wistar King Aptakeman rats. All animals given a single dose died of renal cortical necrosis within 7 days. Injected PVA-BSA complex was localized in the glomerular capillary lumina in a pattern of thrombosis. All animals given daily injections of a small dose for 5 days developed acute proliferative glomerular lesions accompanied by a significant deposition of IgG, IgM and C3 in the mesangium in which the PVA-BSA complex had been localized. The subsequent deposition of immunoglobulins and complement was suggestive of a possible mechanism of local immune complex formation in the development of the present proliferative glomerular lesions.

Acute Disease↗
PubMed1980

Polyvinyl alcohol toxicosis as a model of glomerulonephritis in Beagle dogs.

Investigation of pharmacokinetics of certain drugs in experimental models of glomerulonephritis would facilitate development of dose schedules for dogs with this disease. Polymerized polyvinyl alcohol (PVA)-induced glomerulonephritis was investigated in healthy, 15-week-old purebred Beagle dogs. Three dogs were injected daily with 20 ml of 5% (w/v) PVA (125,000 molecular weight, 88% hydrolyzed) in phosphate-buffered saline solution. One control was given only phosphate-buffered saline solution. Determinations were made of complete blood count, PCV, serum urea nitrogen, specific gravity, urine pH, and protein. Tissue specimens were taken for light microscopic and electron microscopic examinations. Injections were stopped after 3 weeks due to severe CNS depression and anemia in the principals. Proteinuria appeared shortly before dogs were euthanatized, but there were no other signs of renal disease. The dominant lesions were foam cell formation in glomeruli and diffuse vacuolation of splenic red pulp cells. Lesions were also visible in electron microscopic sections of glomeruli. Abnormalities were not observed in the control dog. Due to the severity of the nonrenal lesions, PVA (the type used here) is not useful for creating a model of renal disease in dogs.

Animals↗
PubMedDate not supplied

Polyvinyl alcohol particle size and suspension characteristics.

PURPOSE: To evaluate the size and shape of commercially available polyvinyl alcohol (PVA) particles and to determine whether they change in size when suspended in nonionic contrast and in a solution of nonionic contrast and absolute alcohol. METHODS: The two-dimensional area and the long and short axis of PVA particles from several different vendors were measured using a light microscope attached to a video system and an image-processing software program. Particles were measured as packaged (dry or suspended in saline), suspended in ioversol, and suspended in ioversol containing 30% alcohol. RESULTS: All brands of dry particles had similar microscopic appearances. The saline-suspended particles had fewer and finer perforations. After suspension in contrast, all sizes and brands of dry particles significantly increased in size. The particles packaged in saline did not expand. The addition of alcohol to the contrast did not consistently change particle size. Particle aggregation was similar in both contrast suspensions for all groups of particles. Particles less than 50 microns in size were rarely observed in any PVA preparation after suspension. CONCLUSIONS: The three dry PVA preparations seem to be similar. All increase significantly in size when suspended in nonionic contrast or contrast-alcohol solutions. The saline-packaged PVA particles were different from the dry variety and did not enlarge in contrast or contrast-alcohol solutions. Alcohol did not change the size or suspension characteristics of PVA particles. Particles less than 50 microns in size were rarely identified.

Contrast Media↗
PubMed1994

Polyvinyl alcohol enhances detection of low abundance transcripts in early stage quail embryos in a nonradioactive whole mount in situ hybridization technique.

We have tested the ability of polyvinyl alcohol (PVA) to enhance the indoxyl-nitro blue tetrazolium alkaline phosphatase color reaction in whole mount in situ hybridizations of early stage quail embryos. Using detection of the myogenic factor qmyoD in hybridizations of 13-14 somite-pair quail embryos as a test system, 10% solutions of 13-23 kDa and 31-50 kDa PVA optimally enhanced the alkaline phosphatase color reaction. With the enhanced detection conditions, we have been able to measure qmyoD expression as early as the 3 somite-pair stage, whereas previously we were unable to detect qmyoD prior to the 10 somite-pair stage. PVA-enhanced detection of somitic qmyoD expression was specific as no corresponding signal was found in control hybridizations with a sense qmyoD probe.

Animals↗
PubMed1994

Clinical response to intravenous nitroglycerin infused through polyethylene or polyvinyl chloride tubing.

The effects of polyethylene and polyvinyl chloride (PVC) administration sets on the clinical response to i.v. nitroglycerin were studied. Patients with ischemic heart disease were randomly assigned to receive nitroglycerin solution through either a polyethylene administration set or a PVC set. The rate of the infusion was 5-10 micrograms/min initially and was adjusted upward by 5-10 micrograms/min every 5-10 minutes until anginal symptoms were relieved or an adverse effect limited further increases. The data collected included patient demographics, the indication for nitroglycerin, nitroglycerin dosages, the initial dosage-adjustment time (the time necessary to reach the initial effective dosage), the number of dosage adjustments and the indications for them, the duration of the infusion, the time of tubing changes, the total dose of nitroglycerin, the amounts of sublingual nitroglycerin and i.v. morphine used, and the occurrence of various clinical events. There were 78 courses of therapy in the PVC group and 62 in the polyethylene group. The two groups were comparable in all respects except gender. There were no significant differences between the two groups in any of the primary study variables. Patients who received i.v. nitroglycerin through a PVC administration set had the same clinical response as patients given the drug through a polyethylene set.

Aged↗
PubMed1994

[Immunocryoultramicrotomy (gelatin embedding and polyvinyl alcohol embedding methods): its procedures, usefulness, and limitations--application to human blood cells].

Cryoultramicrotomy applying immunogold staining (immunocryoultramicrotomy) is a useful method to demonstrate the localization of antigens in biological specimens. Recently, we have developed a modified method for immunocryoultramicrotomy using gelatin as an embedding medium (gelatin embedding method). In this study, we compared the results obtained by the gelatin embedding method with those obtained by a conventional method applying polyvinyl alcohol embedding (PVA embedding method). Both methods were easy to perform, and yielded fairly satisfactory results in terms of detecting antigens and preserving ultrastructures. According to the gelatin embedding method, membranes enclosing organelles revealed a negatively stained image, and organelles were clearly delineated by an electron-lucent layer. In contrast, a positively stained image was obtained by the PVA embedding method; however, the delineation of organelles was somewhat inferior to that of the gelatin embedding method. Although these methods were useful to detect various biological antigens, they had some limitations in sensitivity. Prior glutaraldehyde fixation was requisite for cryosectioning and preserving ultrastructures, but it caused the loss of antigenicity to some extent. This should be taken into account when evaluating the results obtained by immunocryoultramicrotomy. In this paper, we present the detailed procedures of the gelatin embedding method, as well as the PVA embedding method, and demonstrate the localization of myeloperoxidase, lysozyme and CD3 molecules in human blood cells using both methods.

Antibodies, Monoclonal↗
PubMed1994

Storage of lorazepam in three injectable solutions in polyvinyl chloride and polyolefin bags.

The stability of lorazepam 0.1 mg/mL in three intravenous infusion solutions in polyvinyl chloride (PVC) and polyolefin bags at 37, 24, 4, and -20 degrees C was evaluated over seven days of storage. Triplicate test solutions of lorazepam 0.1 mg/mL in 50-mL PVC bags and 50-mL polyolefin bags containing 0.9% sodium chloride injection, 5% dextrose injection, and lactated Ringer's injection were prepared and stored at 37, 24, and 4 degrees C. Samples were removed initially and at various times over seven days and analyzed for lorazepam content. In addition, lorazepam 0.1 mg/mL in 5% dextrose injection in polyolefin bags was stored at -20 degrees C and samples were removed initially and after seven days and analyzed for lorazepam content. The rate of lorazepam sorptive loss to PVC bags was evaluated with lorazepam 0.1 mg/mL in 5% dextrose injection in PVC bags and stored at 24 degrees C. Samples were removed initially and after two, four, six, and eight hours. High-performance liquid chromatography was performed in duplicate on each sample for lorazepam quantitation. Rapid loss of lorazepam occurred in all samples stored in PVC bags. After seven days at 4 degrees C, 8-9% was lost from 0.9% sodium chloride injection and 5% dextrose injection. At 24 degrees C, 17% was lost in 24 hours; at 37 degrees C, 27-29% was lost in 24 hours. About 10% of the lorazepam was lost from the lactated Ringer's solution in PVC bags after three days at 4 degrees C; 25% was lost in 24 hours at 24 degrees C; and 25% was lost in eight hours at 37 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMedDate not supplied

Insulin release from a bioartificial pancreas using a mesh reinforced polyvinyl alcohol hydrogel tube. An in vitro study.

Islet transplantation with a bioartificial pancreas is a potential alternative to whole pancreas transplantation. The authors constructed a bioartificial pancreas using mesh reinforced polyvinyl alcohol hydrogel tubes (MRPT), in an attempt to clarify the in vitro responsiveness to glucose of islets seeded in the MRPT. When the MRPT were perfused in a small chamber with buffer containing 3.3 mmol or 16.7 mmol glucose, insulin release from the MRPT began to increase at 9 +/- 3 min, reaching a plateau at approximately 40 min after the glucose concentration in the perfusate increased from 3.3 to 16.7 mmol. When MRPT seeded with islets were subjected to static incubation in buffer containing 3.3 mmol or 16.7 mmol glucose, insulin release from the MRPT remained elevated for 3 hr of high glucose stimulation, the amount of secreted insulin depending upon the number of islets seeded. Although pre incubation of semipermeable membranes in culture medium containing fetal bovine serum prior to seeding with islets has recently been reported to improve insulin release, the authors found that such pre treatment of the MRPT did not have a beneficial effect. Their in vitro findings in this study suggest that the bioartificial pancreas using MRPT could be a promising therapeutic approach to human diabetes mellitus.

Animals↗
PubMed1993

[Effect of immobilization of analgin in polyvinyl alcohol on its mutagenicity in mice].

Mutagenicity of analgin in the tests for sperm head anomalies (SHA) and chromosome aberrations (CA) in bone marrow cells was studied in male mice Mus musculus. Analgin (40 micrograms) was injected intraperitoneally in 0.2 ml of aqueous solution or 0.01-5% solution of polyvinyl alcohol (PVA). Analgin was found to increase both SHA and CA frequencies. The drug immobilized in PVA also increased SHA and CA frequencies, though in less degree than non-immobilized one.

Animals↗
PubMed1993

[Effect of immobilization of amidopyrine in polyvinyl alcohol on mutagenicity of yeast].

Frequency of gene mutations was studied on the yeast Saccharomyces cerevisiae after treatment with amidopyrine (AP) and polyvinyl alcohol (PVA). PVA was found to have no mutagenic activity, whereas AP increased mutation frequency in dependence of drug concentrations (15 and 30 mg/ml) and the duration of cell treatment (4 and 24 hours). Immobilization of AP in PVA led to decrease in drug mutagenicity.

Aminopyrine↗
PubMed1993

Esophageal dilation with polyvinyl bougies, using a marked guidewire without the aid of fluoroscopy: an update.

One hundred thirty-eight patients with esophageal stricture underwent polyvinyl bougie dilations whereby American Endoscopy dilators were passed over a marked guidewire that had been placed endoscopically. Fluoroscopy was not utilized during the dilations. The dilations were performed only after the guidewire was properly placed, with 60-cm markings at the incisors, which ensured that the tip of the guidewire was in the antrum. One hundred fourteen patients had benign strictures and 24 had malignant strictures. There were 197 sessions of dilations for a total of 748 individual dilations. In 97 of 138 patients, the guidewire was placed in the antrum under direct vision. The remaining 41 patients had significant esophageal stenosis which prevented passage of the endoscope into the stomach; therefore, the guidewire was placed by advancing it blindly through the stenosis. There were no procedure-related complications. During this period, eight patients were dilated without complications, using fluoroscopic placement of guidewire because endoscopic placement of the guidewire was not considered safe. We conclude that esophageal strictures can be safely dilated in most patients by means of the American Endoscopy dilator system and the marked guidewire without the aid of fluoroscopy.

Adult↗
PubMed1993

Leaching of diethylhexyl phthalate from polyvinyl chloride containers by selected drugs and formulation components.

The extent of leaching of diethylhexyl phthalate (DEHP) from polyvinyl chloride (PVC) bags by several organic solvents and surfactants used as formulation components and by 12 drug products containing these solvents and surfactants was studied. The organic solvents ethanol, polyethylene glycol, and propylene glycol, the surfactants polysorbate 80 and polyoxyethylated castor oil, and the 12 drugs were admixed separately in PVC bags of 5% dextrose injection. At the time of preparation and after 4, 8, and 24 hours at 24 degrees C, the concentration of DEHP in duplicate samples was determined in duplicate by high-performance liquid chromatography. Ethanol, polyethylene glycol, and propylene glycol at concentrations of 25% and the drugs containing these components did not leach DEHP within the study period. Polysorbate 80 1% to 25% leached detectable amounts of DEHP in as little as one hour at the high concentration and within four hours at the lower concentrations; at 24 hours, DEHP concentrations ranged from 36 micrograms/mL for 1% polysorbate 80 to 237 micrograms/mL for 25% polysorbate 80. Similar results were observed for polysorbate 80 plus ethanol and for polyoxyethylated castor oil plus ethanol. Drug products containing surfactants, including cyclosporine, miconazole, and teniposide, and the vehicles used in formulating taxol and taxotere, leached relatively large amounts of DEHP in 24 hours. Smaller amounts were leached by chlordiazepoxide hydrochloride and etoposide. DEHP was leached from PVC containers by a variety of surfactants and drug products containing these surfactants. Drugs that leach DEHP should be prepared in non-PVC containers and administered through non-PVC tubing.

Chemistry, Pharmaceutical↗
PubMedDate not supplied

Extended preoperative polyvinyl alcohol microembolization of intracranial meningiomas: assessment of two embolization techniques.

PURPOSE: To evaluate the efficacy of preoperative meningioma devascularization with small polyvinyl alcohol (PVA) particles. METHODS: In 34 patients with intracranial meningiomas, CT, MR, 1H MR spectroscopy, MR volumetric measurements, intraoperative ultrasound, and histopathologic findings were used to compare the efficacy of two embolization techniques: 1) administration of 150- to 300-microns PVA particles in the usual suspension, and 2) administration of 50- to 150-microns PVA particles in a highly diluted suspension. RESULTS: Angiography after embolization demonstrated the total elimination of tumor blush in all patients. Contrast-enhanced MR after the administration of 150- to 300-microns PVA particles revealed a reduction of tumor enhancement in only two out of 14 patients. Only after the use of small particles could significant tumor necrosis be depicted on MR and confirmed histopathologically after surgery. In 12 of 20 patients, 30% to 95% of the whole tumor was necrotic with 17% to 20% reduction of tumor volume in four cases, leading to recovery from the initial neurologic deficits. In three of 20 patients without sufficient steroid medication before the treatment, tumor swelling occurred. Postembolization MR disclosed a tumor volume increase of 10% to 20% in these patients. 1H MR spectroscopy of the tumors showed an increase of lactate and aliphatic lipid compounds after embolization, indicating tumor infarction. Surgical removal of effectively embolized meningiomas without significant blood loss was possible. The appearance of the tumor at operation, ultrasound examination, and the histopathologic examination of different parts of the tumor confirmed the preoperative MR findings suggesting necrosis. CONCLUSION: Extended microembolization with 50- to 150-microns PVA particles improves the surgical treatment of meningiomas, as compared with larger particle embolization. It may also be the only treatment required in older or high-risk patients. The protective effect of steroid medication before the endovascular treatment of meningiomas is suggested by our study.

Adult↗