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K Wieczorowska-Tobis

Publications and source records attributed to K Wieczorowska-Tobis.

At least 19 recordsLinked to original sources
PubMed2006

Difference in estimated GFR with two different formulas in elderly individuals.

The aim of this study was to characterize the differences between the prediction of GFR with Cockcroft-Gault formula (CG=(140-age)/(72 x PCr (mg/ml), for females multiplied by 0.85) and the new formula based on the multicenter trial of the Modification of Diet in Renal Diseases (MDRD=186 x P (Cr) (-1.154) x age(-0.203); 0.742 if patient is female) in elderly subjects. The study involved 100 individuals aged 65-111 years (mean age 88.3+/-14.7; 79 females and 21 males). In all subjects GFR was estimated according to both formulas mentioned above and expressed in ml/min/1.73 m2. Thereafter we calculated the difference between MDRD and CG (MDRD-CG) and analyzed its determinants in every subject. Mean GFR, obtained with MDRD was 76.0+/-24.0, whereas according to CG 67.9+/-18.6 (p < 0.0001). However, the mean MDRD-CG was up to 30.0+/-26.6 which means that MDRD results were much higher in comparison with CG. Using the multiple linear regression analysis we showed that MDRD-CG strongly depend on age (p < 0.0001), BMI (p < 0.0001) and serum creatinine concentration (p<0.0001). However, the gender has not effect on MDRD-CG value. The values of MDRD-CG strongly and positively correlated with age (r=0.7027, p < 0.0001) and negatively both with body mass index (r=-0.7171, p < 0.0001) and serum creatinine (r=-0.5590, p < 0.0001). In summary, our results show that the difference between MDRD and CG strongly depends on age, BMI and Scr. Investigators should be aware of these differences and take it into account in elderly.

Age Factors↗
PubMed2004

Blood pressure in centenarians in Poland.

The objective of the study is assessment of the prevalence and type of hypertension in centenarians in Poland. The investigations included 92 people who had turned 100 years of age, who, within the protocol of the Project of Investigation Polish Centenarians, underwent genetic, anthropometric, psychological and sociological examinations, and whose cardiovascular system was assessed. In the present analysis, we are analysing data concerning their blood pressure (BP) assessed by several measurements (3-6) with the mercury sphygmomanometer on both arms in sitting (if possible) or lying position performed during one visit. Hypertension was diagnosed when average BP value exceeded > or = 160/95 or > or = 140/90 mmHg. The average of age was 101.2 years (range 100-111 years), the respective values for BP were: systolic 146.7 mmHg (99-213 mmHg), diastolic BP--80.3 mmHg (55-114 mmHg) and pulse pressure (PP) 66.4 mmHg (31-129 mmHg). Hypertension diagnosed based on the criterion > or = 160/95 mmHg was found in 29% of subjects, and according to the recent WHO criterion (> or = 140/90 mmHg) in 65% of subjects. PP exceeded 65 mmHg in 44.6%, and was above 50 mmHg in 91% subjects. In conclusion, hypertension occurs less frequently in centenarians, than in the entire population of old people, but it nevertheless cannot be considered a rare condition.

Age Factors↗
PubMed2004

Kidney function estimated with different formulas in centenarians.

PURPOSE: There are growing doubts about the accuracy of Cockcroft-Gault formula (CG) used for the estimation of creatinine clearance, especially in elderly. Recently, the authors of the multicenter trial of the Modification of Diet in Renal Diseases (MDRD) have proposed a new equation. Moreover, Baracskay et al. (B), proposed the special formula for the estimation of kidney function (KF) in elderly. The aim of our study was to compare the results of KF calculated with these three formulas in centenarians. MATERIAL AND METHODS: The study involved 50 centenarian subjects aged 100-111 years (41 females and 9 males) who participated in Polish Centenarians Program. In all of them KF was estimated with the CG, B and MDRD formulas. RESULTS: In the whole population examined, the mean KF according to CG was lower in comparison to both others (p < 0.001 vs both B and MDRD). Also, in females CG results were the lowest (p < 0.001 vs both B and MDRD). In contrast, KF calculated according to CG and B did not differ in males. The results of the MDRD formula significantly exceeded the two others also in males (p < 0.001 vs CG and B). No impact of gender on the obtained results could be found when CG and MDRD were used. However, according to B, the mean values for females were higher (p < 0.01). CONCLUSIONS: KF calculated with the CG, B and MDRD formulas significantly differed in the centenarians examined. Thus, further studies, which include a reference standard, are necessary to answer the question which of these mathematical formulas is the most reliable for the calculation of KF in the elderly.

Aged↗
PubMed2002

The ultrastructure of the peritoneal membrane in chronically dialysed rats with spontaneous peritonitis: preliminary observations.

In this paper we describe ultrastructure of the peritoneal membrane from single peritoneal biopsies collected from chronically dialysed rats with spontaneous peritonitis. The results were compared with those obtained in chronically dialysed animals without peritonitis. In rats with peritonitis, peritoneum was much thicker than in peritonitis-free animals. The increased thickness of the peritoneum during peritonitis was due to infiltration of the submesothelial tissue with oedematous fluid and to the presence of huge amount of cells in the stroma. The connective tissue cells were accumulated just underneath the peritoneal surface. In deeper parts of the interstitium, infiltrating acute inflammatory cells were present (lymphocytes, polymorphonuclear cells: neutrophils and eosinophils). Inversely, the increased thickness of the peritoneum in peritonitis-free animals was mainly due to enhanced amounts of collagen. Additionally, in rats with peritonitis, the surface was often denuded of mesothelial cells. The damaged mesothelial cells that detached from the peritoneal surface were also found. In conclusion, the morphological changes observed in rats with peritonitis are similar to those reported in humans, thus the model of peritonitis in dialysed rats can be used for the study of peritoneal remodeling during peritoneal dialysis complicated by peritonitis.

Animals↗
PubMed2002

Pathophysiology of ageing.

Ageing is characterized by a gradual decline in organ functional reserves which reduces the ability to maintain homeostasis under conditions of stress. Introduction of cell culture and molecular biology techniques has provided new experimental tools for the analysis of ageing at the molecular level. During ageing progressive degeneration of cells and loss of regenerative capacity are enhanced and with time the alterations caused by them ultimately lead to death. In this paper the current knowledge of the mechanisms of ageing is summarized.

Aging↗
PubMed2001

Plasma glutathione peroxidase activity in the elderly.

Schiavon et al. (1994) have reported that the measurement of plasma glutathione peroxidase activity (PGP) could provide an index of renal function. Its activity, which was depressed in patients with impaired renal function, correlated positively with creatinine clearance and negatively with serum creatinine. To evaluate the hypothesis that the plasma PGP activity may be used to assess renal function in elderly, we measured the plasma PGP and creatinine clearance (ClCr) in 65 active, community-dwelling elderly (range: 65-93 years; 47 women and 18 men). We did not include persons with advanced renal failure in our study. PGP did not correlate with PCr and it was similar among patients with normal and with increased PCr (127.0 +/- 30.7 U/l and 119.7 +/- 21.6 U/l, respectively). A positive correlation was found between PGP and ClCr (r = 0.30; p < 0.01). Plasma PGP activity was lower in patients with a ClCr lower than 70 ml/min/1.73 m2 than in those who had a higher ClCr (113.0 +/- 25.8 U/l and 131.2 +/- 26.7 U/l, p < 0.01). However, no correlation was found between ClCr and PGP in subjects with lower ClCr. PGP did not correlate with age but there was a correlation between ClCr and age (r = -0.24, p < 0.05). Our results suggest that plasma PGP activity is decreased in the patients with impaired renal function but this decrease does not correlate with age-dependent decline of kidney function.

Aged↗
PubMed2001

Multidirectional approach to study peritoneal dialysis fluid biocompatibility in a chronic peritoneal dialysis model in the rat.

BACKGROUND: Peritoneal dialysis causes the functional and morphological changes in the peritoneum that result from the bioincompatibility of dialysis solutions. We present a model of chronic peritoneal dialysis in the rat that can be used for testing the biocompatibility of dialysis fluids. Methods and Results. Long-term exposure of the peritoneum to dialysis solutions can be performed in rats with implanted peritoneal catheters. Sampling of the dialysate allows the evaluation of intraperitoneal inflammation by examining cell differential and dialysate cytokine levels. Peritoneal permeability can be evaluated at designed time intervals with the peritoneal equilibration test (PET). At the end of dialysis, peritoneal histology is studied with light and electron microscopy. CONCLUSIONS: Such a multidirectional approach is an effective way to test biocompatibility of dialysis solutions.

Animals↗
PubMed2001

The ultrastructure of the peritoneal membrane in chronically dialysed rats.

The model to estimate peritoneal function in chronically dialysed rats was previously presented by us. The aim of the paper is to report the findings obtained in electron microscopy of peritoneal biopsies from Wistar rats dialysed for 1 month with high glucose dialysis solution. In control animals, thin mesothelial cells were covered with microvilli. The submesothelial tissue was composed of sparse bundles of parallelly oriented collagen fibers with a few resting cells. In chronically dialysed rats, mesothelial cell layer was thicker and cells were fully packed with intracellular structures, mainly secretory granules with a homogeneous content. The submesothelial tissue was expanded due to the increased amount of collagen fibers, oedema and increased amount of submesothelial cells which were activated. The use of electron microscopy to study the peritoneum in dialysed rats is an excellent supplement to the chronic functional model of peritoneal dialysis in rats.

Animals↗
PubMed2001

A comparison of the biocompatibility of phosphate-buffered saline and dianeal 3.86% in the rat model of peritoneal dialysis.

Phosphate-buffered saline (PBS), an isotonic solution with a physiologic pH can be considered an example of a biocompatible dialysis fluid. This study compared the biocompatibility of PBS with that of Dianeal 3.86% (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.), using a model of peritoneal dialysis in the rat. In an acute experiment, after catheter implantation, rats were infused on day 1 with PBS, on day 5 with standard dialysis solution (Dianeal 3.86%), and on day 7 again with PBS. When rats were injected with Dianeal 3.86%, the inflammatory reaction was suppressed as compared with PBS. The cell count was lower with Dianeal (-85%, p < 0.001), the neutrophil:macrophage ratio in dialysate was 80% lower (p < 0.01), total protein concentration in the Dianeal dialysate was 73% lower (p < 0.01), and the dialysate nitrite level was 45% lower (p < 0.01). In a chronic experiment, after catheter implantation, rats were dialyzed for four weeks with PBS or with Dianeal 3.86%. At the end of the study, a 1-hour peritoneal equilibration test (PET) was performed. As evaluated on a semiquantitative scale, macroscopic changes in the peritoneum were more severe in rats exposed to PBS than in those exposed to Dianeal 3.86% (8.6 +/- 3.2 vs 5.2 +/- 2.6, p < 0.05). The thickness of the visceral peritoneum was comparable in both groups; but, in PBS-treated rats, the peritoneal interstitium contained more inflammatory cells and more new vessels. During the 1-hour PET, peritoneal permeability to water and solutes was comparable in the two groups. Despite a more physiologic composition, PBS is a less biocompatible peritoneal dialysis solutions than is standard, acidic, hypertonic dialysis solution.

Animals↗
PubMed2001

Influence of neutral-pH dialysis solutions on the peritoneal membrane: a long-term investigation in rats.

OBJECTIVE: Glucose degradation products (GDPs) and low pH are potential causes of bioincompatibility of peritoneal dialysis fluids (PDFs). The aim of the present study was to compare the effect of 6 weeks' exposure of the peritoneum in rats to two different PDFs: a standard PDF with a low pH and high level of GDPs (CAPD 3: Fresenius Medical Care, Bad Homburg, Germany), and a modified PDF with a low level of GDPs and a physiologic pH (CAPD 3 Balance: Fresenius Medical Care). METHODS: After catheter implantation, rats were exposed twice daily for 6 weeks to CAPD 3 fluid or to CAPD 3 Balance. At the beginning and at the end of the study, a 4-hour dwell was performed in every rat to evaluate intraperitoneal inflammation and its effect on total collagen synthesis in the in vitro cultured rat mesothelial cells (ex vivo study). Additionally, after 6 weeks' exposure, the peritoneal cavity was opened, and macroscopic changes were evaluated according to a semiquantitative scale. Peritoneal samples were also taken for morphology study. RESULTS: In rats treated with CAPD 3 fluid, intraperitoneal inflammation was comparable at the beginning and at the end of the experiment. In animals exposed to CAPD 3 Balance, the intensity of the intraperitoneal inflammation decreased during the study (cell count, p = 0.0781; neutrophil:macrophage ratio, p < 0.01; nitrite concentration, p < 0.05; hyaluronan level, p < 0.05). The capacity of effluent dialysate from CAPD 3 rats to activate collagen synthesis in in vitro-cultured mesothelial cells was the same at the beginning and at the end of the study. In the CAPD 3 Balance group, this capacity was statistically significantly lower at the end of the study than at the beginning (p < 0.05). The mean thickness of the visceral peritoneum was comparable in both groups of animals, but, macroscopically, more severe fibrosis was found in the peritoneum of rats exposed to CAPD 3 as compared with animals treated with CAPD 3 Balance (p < 0.05). CONCLUSION: We showed that, in the rat model of peritoneal dialysis, chronic exposure of the peritoneum to PDFs with low GDPs and a physiologic pH diminished the intraperitoneal inflammatory reaction induced by dialysis, and reduced peritoneal fibrosis.

Animals↗
PubMed2001

Morphologic aspects of chronic peritoneal dialysis in a rat model.

OBJECTIVE: We previously put forward an experimental model for evaluating peritoneal function in chronically dialyzed rats. In the present paper, we show the morphologic alterations detected by electron microscopy in the peritonea of chronically dialyzed rats. MATERIALS AND METHODS: The study was done in male Wistar rats. Animals were divided into two groups: control (non dialyzed) rats and dialyzed rats [intraperitoneally exposed to Dianeal 3.86% (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.) for 1 month]. At the end of the study, the rats were humanely killed by bleeding, and samples of the visceral peritoneum covering the liver were taken from 3 rats in each group. The samples were examined by transmission electron microscopy (TEM). RESULTS: In control rats, the peritoneum was composed of flattened mesothelial cells covering the thin layer of the submesothelial connective tissue (ST), containing few fibroblasts. In dialyzed animals, a dramatic expansion of the ST was found. We saw compartmentalization of the ST, with changed morphology of the fibroblasts, altered organization of collagen fibers, and changes in the cells infiltrating the ST. Apart from the fibroblasts, mast cells were relatively numerous. CONCLUSIONS: Our work underlines the capabilities of morphology studies in an animal model for assessing peritoneal dialysis fluid biocompatibility.

Animals↗
PubMed2001

Comparison of the biocompatibility of phosphate-buffered saline alone, phosphate-buffered saline supplemented with glucose, and dianeal 3.86%.

OBJECTIVE: We compared the effects of intraperitoneal infusion of phosphate-buffered saline (PBS, pH 7.4), of PBS supplemented with 3.86% glucose (G), and of standard dialysis solution [Dianeal 3.86%: Baxter Healthcare Corporation, Deerfield, IL, U.S.A. (D)] on intraperitoneal inflammation in dialyzed rats. METHODS: After catheter implantation, rats were infused on day 1 with PBS, on day 3 with PBS+G, on day 5 with D, and on day 7 again with PBS (PBS-2). After a 4-hour dwell, dialysate samples were collected and analyzed. RESULTS: All dialysate parameters studied [dialysate cell count, neutrophil:macrophage ratio (Ne:Ma), and total protein], except tumor necrosis factor alpha (TNFalpha), were comparable during both PBS infusions. During dialysis with PBS+G, the inflammatory response was suppressed as compared with the first dialysis with PBS (cell count, p < 0.001; Ne:Ma, p < 0.05; TNFalpha, p < 0.001; total protein, p < 0.001). During dialysis with D, peritoneal inflammatory parameters were further suppressed (cell count, p < 0.001 vs PBS and p < 0.01 vs PBS+G; Ne:Ma, p < 0.001 vs PBS and p < 0.05 vs PBS+G; TNFalpha, p < 0.001 vs PBS and p < 0.001 vs PBS+G; total protein, p < 0.001 vs PBS and p < 0.01 vs PBS+G). CONCLUSIONS: Hypertonicity of the dialysis fluid suppresses intraperitoneal inflammatory parameters in rats. The suppression was even more severe when Dianeal 3.86% was used. That finding could be due to the low pH and presence of GDPs in the fluid.

Animals↗
PubMed2000

Dialysis solution containing hyaluronan: effect on peritoneal permeability and inflammation in rats.

BACKGROUND: Hyaluronan (HA), a high molecular weight mucopolysaccharide found in interstitial tissues and fluid, is lost from the peritoneal cavity during peritoneal dialysis. In order to determine the role of HA in peritoneal function, we investigated the effects of exogenous HA on peritoneal permeability, markers of intraperitoneal inflammation, and peritoneal morphology in rats exposed to peritoneal dialysis solution for four weeks. METHODS: Wistar rats were infused intraperitoneally, twice daily, with conventional, hypertonic dialysis solution (Dianeal 3.86%; control) or Dianeal solution containing 10 mg/dL of high molecular weight HA. Peritoneal permeabilities and clearances of solutes and protein were determined using a modified peritoneal permeability test (peritoneal equilibration test) at the beginning and the end of the treatment. Peritoneal volume and ultrafiltration were determined using a macromolecular marker and by gravimetric methods. Peritoneal inflammation was determined by cell counts and differential and by the measurement of cytokine concentrations in the dialysate effluent. Peritoneal thickness and HA content were determined in liver and mesentery biopsies taken at the end of the experiment. RESULTS: After four weeks of exposure to the dialysis solution, transperitoneal protein equilibration was significantly lower in HA-treated rats compared with rats treated with Dianeal alone (46% lower for albumin, P < 0.003; 33% lower for total protein, P < 0.001). The total drained volume after a four hour dwell was 29% higher in the HA group compared with the control (P < 0.001), yielding a positive net ultrafiltration in the HA group versus a negative net ultrafiltration in controls. Peritoneal clearances of urea and creatinine tended to be elevated in HA-treated rats, while clearances of total protein and albumin tended to be lower. Dialysate effluent from rats exposed to HA contained a lower percentage of neutrophils (8.8 +/- 22.8 +/- 9.5%, P < 0.01) and lower levels of the cytokines, tumor necrosis factor-alpha (11.2 +/- 14.7 vs. 42.3 +/- 35.3 pg/mL, P < 0.05) and monocyte chemoattractant protein-1 MCP-1 (72.0 +/- 86.5 vs. 402.4 +/- 258.3 pg/mL, P < 0.02), compared with rats treated with Dianeal alone. The thickness of the peritoneal interstitium showed a similar increase in both groups, but mesenteric tissue from the HA group contained more HA (48%, P < 0.01) than tissue from control animals. CONCLUSIONS: The addition of HA to peritoneal dialysis solution decreases protein permeability, increases ultrafiltration, and decreases cytokine levels and the proportion of peritoneal neutrophils in dialysate from rats exposed to hypertonic dialysis solution. These results suggest that exogenous HA may help to protect the peritoneal membrane during exposure to dialysis solutions. These benefits, if sustained in the clinical setting, could lead to improvements in the therapy of peritoneal dialysis.

Animals↗
PubMed2000

Hypertonicity of dialysis fluid suppresses intraperitoneal inflammation.

We studied acute and chronic intraperitoneal inflammation during dialysis performed in rats injected with phosphate-buffered saline alone (PBS) or PBS supplemented with glucose (Glu) or with mannitol (Man). In acute experiments, the result of a first dialysis with PBS in every rat (dialysis I) was compared with a second dialysis performed 24 hours later (dialysis II) using a different dialysis fluid: either PBS with 3.86 g/dL Man or PBS with 3.86 g/dL Glu. In rats exposed to hypertonic dialysis solutions (both Glu and Man), inflammatory reaction was decreased (cell count: p < 0.05; nitric oxide secretion: p < 0.05; protein in dialysate: p < 0.05). In control animals treated only with PBS (dialysis I and dialysis II), the inflammatory reactions during dialysis I and dialysis II were comparable. In chronic experiments, rats were dialyzed with the tested fluids for four weeks. Weekly, dialysate samples were taken and analyzed. At the end of the study, cell counts and protein losses were higher in the PBS-treated rats than in the other groups (cell count: p < 0.05, Glu vs PBS, and p < 0.05, Man vs PBS; protein in dialysate: p < 0.001, Glu vs PBS, and p < 0.01, Man vs PBS). We conclude that hypertonicity of the dialysis fluid inhibits the inflammatory reaction in the peritoneal cavity during peritoneal dialysis.

Acute Disease↗
PubMed2000

Antioxidant defense in centenarians (a preliminary study).

The study was designed to assess the antioxidant defense mechanisms, either enzymatic or non-enzymatic, in a group of sixteen centenarians (one male and fifteen female subjects aged 101 to 105 years) living in the Upper Silesia district (Poland) in order to evaluate the potential role of antioxidant defenses in human longevity. The results of our preliminary study showed that in comparison with young healthy female adults the centenarians had significantly higher red blood cell glutathione reductase and catalase activities and higher, although insignificantly, serum vitamin E level.

Adult↗
PubMed1999

Effect of N-acetylglucosamine on function of peritoneal leukocytes.

OBJECTIVE: To compare effects of N-acetylglucosamine (NAG)-based and glucose-based dialysis fluids on the function of peritoneal leukocytes in conditions of peritoneal dialysis. DESIGN: In vitro experiments on ex vivo isolated rat peritoneal leukocytes. MATERIALS: Peritoneal leukocytes were isolated from rats on chronic peritoneal dialysis. On alternate days, fluid exchanges were performed with NAG-based or glucose-based dialysis solutions. After a 4-hour dwell, dialysate was drained and peritoneal leukocytes were incubated in vitro +/- lipopolysaccharide (LPS). Production of nitrites (index of NO synthesis), tumor necrosis factor alpha (TNFalpha), interleukin-1beta (IL-1beta), and interferon gamma (IFN-gamma) by unstimulated or stimulated peritoneal leukocytes originating from NAG-based or glucose-based fluid was measured. RESULTS: Dialysate cell count was lower during exchanges with NAG-based fluid (2113+/-615 cells/microL) as compared to glucose-based fluid (3643+/-1108 cells/microL; p < 0.01). Differential cell count was similar in both studied groups. Unstimulated peritoneal leukocytes from NAG-based dialysate produced more NO (nitrites) (0.65+/-0.07 micromol per 10(6) cells) than did cells from glucose-based dialysate (0.26+/-0.09 micromol per 106 cells, p < 0.01). Stimulated peritoneal leukocytes from NAG-based dialysate produced more cytokines than did cells from glucose-based dialysate: TNFalpha, 135.2+/-37.0 pg versus 70.2+/-21.8 pg per 10(6) cells respectively, p < 0.01; IL-1beta, 143.2+/-60.9 pg versus 99.1+/-22.4 pg per 10(6) cells respectively, p < 0.05; IFN-gamma, 16.2+/-12.5 pg versus 6.0+/-1.8 pg per 10(6) cells respectively, p < 0.01. CONCLUSIONS: We demonstrated that rat peritoneal leukocytes exposed in vivo to NAG-based dialysis fluid have better ability to produce inflammatory mediators than do peritoneal leukocytes from the same donor, but exposed in vivo to glucose-based dialysis solution.

Acetylglucosamine↗
PubMed1999

Bicarbonate/lactate dialysis solution improves in vivo function of peritoneal host defense in rats.

OBJECTIVE: To assess the in vivo peritoneal inflammatory reaction in rats dialyzed with neutral, bicarbonate-lactate-buffered dialysis fluid. METHODS: Chronic peritoneal dialysis was performed for 4 weeks in Wistar rats with two solutions: (1) 40 mmol/L lactate-buffered fluid, pH 5.2, with a glucose concentration of 2.27 g/dL (Lac); and, (2) 15 mmol/L lactate and 25 mmol/L bicarbonate-buffered fluid, pH 7.0-7.5, with a glucose concentration of 2.27 g/dL (Bic-Lac). After 4 weeks, two peritoneal equilibration tests (PET 1 and PET 2) were performed in all animals with each respective solution. PET 1 was done with test solutions alone, whereas, on a subsequent day, PET 2 was performed with test solutions supplemented with endotoxin [lipopolysaccharide (LPS)] to induce peritonitis. RESULTS: During PET 1 no consistent differences were detected in peritoneal permeability between the Lac and Bic-Lac groups. Total dialysate cell count in the Bic-Lac animals was lower than in rats treated with Lac fluid: that is, at 8 hours, the respective counts were 1858+/-524 cells/microL versus 2785+/-1162 cells/microL (p < 0.01). Dialysate from animals dialyzed with Bic-Lac contained more macrophages (at 4 hours: 53.6%+/-35.8% versus 35.8%+/-8.8%, p < 0.001) and fewer neutrophils (at 4 hours: 3.6%+/-1.8% versus 15.4%+/-6.1%, p < 0.001) as compared to those dialyzed with the Lac solution. Concentration of nitrites in 8-hour dwell dialysate samples from Bic-Lac rats was lower than that in the Lac group (0.98+/-0.28 micromol/mL versus 2.32+/-0.87 micromol/mL, p < 0.002), but cytokine levels in the dialysates were comparable. During PET 2, the increase in peritoneal permeability resulting from the LPS-induced inflammatory response was similar for both test solutions. Dialysate cell count was higher in the Lac group versus the Bic-Lac group (at 8 hours: 8789+/-4862 cells/microL versus 3961+/-581 cells/microL, p < 0.001), contained more neutrophils (at 8 hours: 80.0%+/-11.3% versus 54.8%+/-4.4%, p < 0.001) and fewer macrophages (at 8 hours: 6.8%+/-5.6% versus 21.2%+/-3.3%, p < 0.05). During peritonitis, we found a higher overall dialysate concentration of both tumor necrosis factor (TNFalpha: +53%, p < 0.05) and of interferon gamma (IFN-gamma: +303%, p < 0.02), in the Bic-Lac group than in the Lac group. CONCLUSIONS: A lower dialysate cell count, higher percentage of macrophages, and lower percentage of neutrophils in dialysate suggest that Bic-Lac fluid induces a diminished nonspecific inflammatory response of the peritoneal cavity during dialysis. However, after in vivo stimulation, peritoneal cells from animals dialyzed with Bic-Lac solution possess an augmented ability to produce inflammatory cytokines.

Animals↗