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A Breborowicz

Publications and source records attributed to A Breborowicz.

At least 37 records · Page 2Linked to original sources
PubMed1998

The effect of N-acetylglucosamine as a substrate for in vitro synthesis of glycosaminoglycans by human peritoneal mesothelial cells and fibroblasts.

The effect of N-acetylglucosamine (NAG) on in vitro synthesis of glycosaminoglycans by human peritoneal mesothelial cells and fibroblasts was studied. In contrast to isosmotic concentrations of glucose, NAG increases the synthesis of hyaluronan by mesothelial cells and fibroblasts in a dose-dependent manner. This effect of NAG can be demonstrated in the presence of increased glucose levels in a medium, or in a medium mixed with effluent dialysate obtained from continuous ambulatory peritoneal dialysis (CAPD) patients. Glucose inhibits synthesis of sulphated glycosaminoglycans by peritoneal mesothelial cells and fibroblasts, whereas NAG stimulates their production. Our results demonstrate that NAG is an effective stimulator of the in vitro glycosaminoglycans synthesis by human peritoneal mesothelial cells and fibroblasts.

Acetylglucosamine↗
PubMed1998

The characteristics of peritoneal healing after catheter insertion in a rat model of peritoneal dialysis.

The aim of this study was to characterize the process of peritoneal healing after catheter insertion in a rat model of peritoneal dialysis using a 1.36% solution (Baxter Dianeal). After catheter insertion (day 1 of experiment), 12 rats were injected daily with 20 mL of 1.36% dialysis solution for 2 weeks. Every second day a sample of 4 hour dialysate was taken from every rat for biochemical analysis, cell count, cell differentiation, and nitrites measurement. The measured parameters decreased during the experiment and stabilized during the second week after catheter insertion. In cell differentiation, we observed an increase in the number of macrophages, with a parallel decrease in the number of neutrophils that was reflected in a significant decrease in the neutrophils/macrophages ratio. Our results suggest that the process of peritoneal healing after catheter implantation in rats lasts about 2 weeks, and therefore that any biocompatibility study of peritoneal dialysis solutions in rats should be performed at least 2 weeks after catheter insertion.

Animals↗
PubMed1997

In vitro simulation of the effect of peritoneal dialysis solution on mesothelial cells.

All previous in vitro biocompatibility tests of peritoneal dialysis fluids have shown that these have inhibitory effects on the function of peritoneal mesothelium. This report presents results from in vitro experiments performed to study the effect of dialysis fluids (Dianeal 1.36 and Dianeal 3.86; Baxter, Round Lake, IL) on the function of mesothelial cells under conditions that simulate the in vivo state of these solutions in the peritoneal cavity. Thus, cells were initially exposed only to the unused fluids that were thereafter gradually diluted (over 4 hours) with pooled effluent dialysate from continuous ambulatory peritoneal dialysis patients. During the following 20 hours, cells were incubated in a mixture of unused fluid (10% vol/vol) and dialysate effluent (90% vol/vol). The mesothelial cells exposed to dialysis fluids under such conditions became activated cells compared with exposed to dialysate effluent (control) alone. Thus, synthesis by mesothelial cells of all tested substances was enhanced during exposure of the mesothelium to the dialysis fluids: interleukin-6: Dianeal 1.36, +257%; Dianeal 3.86, +181% (both P < 0.05); hyaluronic acid: Dianeal 1.36, +72%; Dianeal 3.86, +63% (both P < 0.05); tissue plasminogen activator: Dianeal 3.86, +33% (P < 0.05); and plasminogen activator/inhibitor-1: Dianeal 1.36, +28%; Dianeal 3.86, +38% (both P < 0.05). Our results show that the peritoneal mesothelium becomes activated when it is exposed to acidic, hyperosmotic dialysis fluids diluted with the dialysate effluent, in a manner that imitates the in vivo changes in these solutions during their intraperitoneal dwell.

Cells, Cultured↗
PubMed1997

[Peritoneum as a dialysis membrane. II. Pathology].

Peritoneal dialysis is an established method of treatment of chronic renal failure. In that paper morphological and functional changes of peritoneum due to the process of long-term dialysis are presented. Morphological changes are observed in mesothelial cells, intercellular junctions, interstitial tissue and blood vessels. Moreover morphological changes in typical complications of chronic peritoneal dialysis, e. g. peritonitis, eosinophilic peritonitis, and sclerosing encapsulating peritonitis are described. Mechanisms of functional disorders during chronic peritoneal dialysis, involving the decreased permeability of the peritoneum, the increased permeability of the peritoneum and the enhanced lymphatic drainage are discussed. The article is the second of two parts presenting physiology and pathology of peritoneum as dialysis membrane.

Biocompatible Materials↗
PubMed1997

Long-term effects of glycylglycine peritoneal dialysis solution with neutral pH on peritoneum in rats.

This study was designed to test the morphological and functional effects of neutral, bicarbonate-based peritoneal dialysis solution containing glycylglycine on the peritoneum of chronically dialyzed rats. Peritoneal dialysis catheters were implanted in 36 rats. The animals were dialyzed twice daily for 4 weeks with a solution containing bicarbonate (35 mmol/L), glycylglycine (10 mmol/L), and 4% of anhydrous glucose (pH 7.35) (group 1; n = 18) or with lactate-based standard 4.25% Dianeal (pH 5.3 (group 2; n = 18). At the beginning of the study, reabsorption of glucose was slower in group 1 (p < 0.02); at the same time, the hyaluronic acid level in the effluent was higher in this group (p < 0.05). However, towards the end of the study these differences disappeared. After 4 weeks of dialysis in rats exposed to bicarbonate-based solution only, the transperitoneal loss of proteins was slower. In morphological studies of the parietal peritoneum, we detected no statistically significant differences between control nondialyzed rats and those exposed to tested solutions. In a biopsy of visceral peritoneum a tendency was observed for increased thickness of peritoneum in rats dialyzed with both tested peritoneal dialysis solutions when compared to control animals. In conclusion, neutral pH glycylglycine peritoneal dialysis solutions seem to be more biocompatible than standard dialysis solutions.

Animals↗
PubMed1997

Alterations of intraperitoneal inflammation by the addition of L-2-oxothiazolidine-carboxylate.

The authors studied the effect of L-2-oxothiazolidine-carboxylate (OTZ), a substrate for intracellular glutathione synthesis, in an in vivo model of lipopolysaccharide (LPS)-induced peritonitis in rats. The addition of LPS to dialysis fluid increased the white blood cell (WBC) count and the nitrite (index of NO synthesis) level in the dialysate. The simultaneous addition of OTZ to the dialysis fluid prevented an increase of WBCs but not of nitrites in the dialysate. Intraperitoneal inflammation was accompanied by a decrease in net transperitoneal ultrafiltration, an increase in the absorption of glucose, and a loss of protein into the dialysate. OTZ partially reversed the effect of peritonitis on net ultrafiltration. Peritoneal leukocytes from rats exposed to LPS showed a reduced concentration of glutathione, an effect that was reversed in the presence of OTZ. These results show that the supplementation of dialysis fluid with OTZ modified the peritoneal reaction to acute inflammation.

Albumins↗
PubMed1997

[Prevalence of allergic diseases in schoolchildren in Krakow and Poznan (based on a standardized ISAAC questionnaire)].

The study population included children aged 6-7 and 13-14 years from primary schools in Kraków (2302 and 2967 children respectively) and Poznań (3132 and 4069 children respectively). The prevalence was assessed using ISAAC questionnaire. In younger age group the number of children with diagnosed asthma and presenting asthma symptoms was significantly higher in Kraków than in Poznań. In older age group higher percentage was observed in Kraków in relation to wheeze ever and nocturnal cough during last year. Pupils from Kraków had symptoms of allergic rhinitis and were diagnosed as allergic rhinitis more frequently than from Poznań. Symptoms suggestive for skin allergy were more often observed in Kraków, but the differences were significant in relation to symptoms during last year in both age groups and in relation to symptoms ever in older age group. Our study revealed discrepancy between the prevalence of symptoms of asthma and allergic rhinitis and the prevalence of established diagnosis.

Adolescent↗
PubMed1997

In vivo model to study the biocompatibility of peritoneal dialysis solutions.

This study was designed to analyze the complex morphologic and functional effects of dialysis solutions on peritoneum in a rat model on chronic peritoneal dialysis. Peritoneal catheters were inserted into 10 male, Wistar rats and the animals were dialyzed twice daily for 4 weeks with 4.25% Dianeal. During the study we observed two opposite effects: healing of the peritoneum after catheter implantation--decreased cell count in dialysate, decreased permeability of the peritoneum to glucose and total protein, increased volume of drained dialysate; and damage to the membrane due to its exposure to peritoneal dialysis solution--increased hyaluronic acid levels in dialysate, a tendency of the peritoneum to thicken when compared to non-dialyzed animals. Our rat model of CAPD may be used for quantitative and qualitative assessment of the effects of peritoneal dialysis solution on the peritoneum during chronic dialysis.

Animals↗
PubMed1996

L-2-Oxothiazolidine-4-carboxylate and N-acetylcysteine as precursors of intracellular glutathione in human peritoneal mesothelial cells.

L-2-Oxothiazolidine-4-carboxylate and N-acetylcysteine as substrates for intracellular glutathione in human peritoneal mesothelial cells were tested. Both substances at concentrations of 0.01 mM and higher augmented the level of glutathione in mesothelial cells. L-2-Oxothiazolidine-4-carboxylate had a milder but more stable effect than N-acetylcysteine. Cells with increased concentrations of the intracellular glutathione were more resistant to injury by free radicals. When used at higher concentrations (> 1 mM), both substances became cytostatic to mesothelial cells as evidenced by growth inhibition.

Acetylcysteine↗
PubMed1996

Intracellular glutathione in human peritoneal mesothelial cells exposed in vitro to dialysis fluid.

Effect of peritoneal dialysis fluids on glutathione (GSH/GSSG) level in human peritoneal mesothelial cells was tested in in vitro experiments. To mimic in vivo conditions, cells were initially exposed to dialysis fluids (Dianeal 1.36%, Dianeal 2.27%, Dianeal 3.86%) that subsequently were diluted with dialysate effluent at time intervals. GSH/GSSG concentration in cells initially decreased but returned to normal values thereafter. This decrease in the intracellular concentration of glutathione was less when pH of the tested dialysis fluid was adjusted to 7.3. In further experiments with mesothelial cells exposed to Earle's salts solution supplemented with glucose and/or lactate, we have shown that in the presence of low pH, lactate is the main factor causing depletion of intracellular glutathione. When added to the dialysis solution at a concentration of 0.1 mM, L-2-oxothiazolidine-4-carboxylate, a precursor of glutathione, not only prevents the initial decrease in glutathione concentration but also augments the final intracellular level of this thiol.

Analysis of Variance↗
PubMed1996

Species-dependent topography of the peritoneum.

Planimetric studies of peritoneal surface area were performed in 10 humans, 12 rabbits, and 15 rats. It was found that the total peritoneal surface area (TPSA) correlated in humans with body surface area (BSA) (r = 0.98, p < 0.0001) and body weight (r = 0.93, p < 0.001), and correlated in animals with body weight (r = 0.80, p < 0.005 in rabbits; and r = 0.88, p < 0.0001 in rats). The area of parietal peritoneum was 18.1 +/- 1.8% of TPSA in humans, 17.8 +/- 1.0% of TPSA in rabbits, and 22.6 +/- 2.1% of TPSA in rats (p < 0.001 vs humans and rabbits). Additionally, the area of peritoneum covering the individual organs (expressed as % of TPSA) was different in humans, rabbits, and rats: for example, the area of peritoneum covering the diaphragm was 6.4 +/- 1.5% of TPSA in humans, which was larger than in animals (3.0 +/- 0.3% in rats, p < 0.0001 vs humans and rabbits; and only 2.1 +/- 0.4% in rabbits, p < 0.0001 vs humans). Presented results show that interspecies variation in the topography of the peritoneum should be taken into account when the results from experimental studies done on animals are extrapolated to humans.

Adult↗
PubMed1996

In vitro detection of hydrogen peroxide in mesothelial cells.

Hydrogen peroxide can be indirectly detected in mesothelial cells by measuring the rate of inhibition of the intracellular catalase activity by 3-amino-1, 2,3-triazole (AT). AT binds and inhibits catalase only in the presence of hydrogen peroxide, and the effect is proportional to the amount of hydrogen peroxide. The effect of AT on catalase activity is prevented in the presence of ethanol. In mesothelial cells in vitro exposed to dialysis fluids (Dianeal 1.36%, 2.27%, and 3.86%) no significantly increased generation of hydrogen peroxide was detected. However, interleukin-1 (IL-1) (10 ng/mL) enhances, within two hours (+40%, p < 0.05), intracellular production of hydrogen peroxide. The presented method of detection of intracellular hydrogen peroxide may be helpful in studies of the pathomechanisms causing mesothelial damage in conditions of peritoneal dialysis.

Amitrole↗
PubMed1996

Effect of vitamin E on peroxidation and permeability of the peritoneum.

Because of the evidence that peritoneal macrophages are activated during peritoneal dialysis, we hypothesised that the injury of the peritoneum is, at least in part, dependent on the intraperitoneal generation of free radicals. The aim of the study was to evaluate the effect of vitamin E on the peroxidation and permeability of the peritoneum during chronic peritoneal dialysis in rats. Supplementation of the intraperitoneally infused saline with vitamin E decreased the peroxidation of peritoneum estimated as the malondialdehyde (MDA) level in rats' omentum. However the permeability of the peritoneum to glucose and protein in vitamin E treated rats was increased. In in vitro study we have found that vitamin E is cytotoxic to human mesothelial cells (HMC) as measured by inhibition of their proliferation and this effect was irreversible. We conclude that vitamin E, despite its antioxidant effect, causes the changes of the peritoneum permeability which could decrease the effectiveness of peritoneal dialysis.

Animals↗
PubMed1996

[Evaluation of the prevalence sensitization to common inhaled allergens in children of school age using skin tests].

The prevalence of sensitization to common inhalant allergens was assessed among schoolchildren using skin prick tests with standard allergen extracts. The results were analysed in relation to asthma and allergy suggestive symptoms. A positive reaction to at least one allergen was observed in 13.5% children. The most frequent was allergy to timothy, then to house dust mite, birch, mugwort, cat dander and dog dander. Children with wheezing, breathlessness and/or rhinitis had significantly more frequent positive test results compared to children without any complaints.

Air Pollutants↗