Phosphorus dynamics during hemodialysis.

We studied phosphorus (P) dynamics and its relation to urea dynamics in a wide range of dialyses by measuring predialysis and postdialysis serum P levels and all removed P and urea in dialysate during 455 hemodialyses. Dialyses were performed at different frequencies (range 3-6 treatments/wk); duration of dialysis (t) (range 80-560 minutes), varied blood and dialysate flow, and with high-flux and low-flux membranes. Kt/V-P, Kt/V-urea, weekly removal of P-and urea and removal volumes (Vr) and their relationships to varying dialyses, and predialysis concentrations, and protein catabolic rates were studied in linear and multiple regression analyses.

Infusion fluids contain harmful glucose degradation products.

Purpose: Glucose degradation products (GDPs) are precursors of advanced glycation end products (AGEs) that cause cellular damage and inflammation. We examined the content of GDPs in commercially available glucose-containing infusion fluids and investigated whether GDPs are found in patients' blood.

Methods: The content of GDPs was examined in infusion fluids by high-performance liquid chromatography (HPLC) analysis.

3,4-dideoxyglucosone-3-ene in peritoneal dialysis fluids infused into the peritoneal cavity cannot be found in plasma.

Objective: Glucose degradation products (GDPs) are important for the outcome of peritoneal dialysis (PD) treatment. The most cytotoxic GDP found in conventionally manufactured fluids, 3,4-dideoxyglucosone-3-ene (3,4-DGE), may in addition be recruited from 3-deoxyglucosone (3-DG). What happens with the GDPs in the fluid infused into patients during PD is not known.

The ideal home hemodialysis machine.

Daily home hemodialysis (HD) patients have a much superior survival rate than patients on regular, 3 times a week in-center HD or on peritoneal dialysis. Present-day HD machines are unsuitable for use at home by patients. We present our concept of the ideal home HD machine that allows daily short and long HD, does all the work preparing for and cleaning up after dialysis, has an intravenous infusion system controlled by the patient, needs no systemic anticoagulation, and teaches and interacts with the patient during dialysis.

3,4-DGE in peritoneal dialysis fluids cannot be found in plasma after infusion into the peritoneal cavity.

Objective: Glucose degradation products (GDPs) are important in the outcome of peritoneal dialysis (PD) treatment. 3,4-dideoxyglucosone-3-ene (3,4-DGE) is the most cytotoxic GDP found in conventionally manufactured fluids and may, in addition, be recruited from 3-deoxyglucosone (3-DG). It is not known what happens with those GDPs in patients during PD.

3,4-DGE is important for side effects in peritoneal dialysis what about its role in diabetes.

Breakdown of glucose under physiological conditions gives rise to glucose degradation products (GDPs). GDPs are also formed during heat sterilization of glucose-containing peritoneal dialysis fluids (PD-fluids). In PD-fluids GDPs have been shown in many different in vitro assays to be responsible for adverse effects such as growth inhibition, and impaired leukocyte function and impaired wound healing of peritoneal mesothelial cells.

How to avoid glucose degradation products in peritoneal dialysis fluids.

Objective: The formation of glucose degradation products (GDPs) during sterilization of peritoneal dialysis fluids (PDFs) is one of the most important aspects of biocompatibility of glucose-containing PDFs. Producers of PDFs are thus trying to minimize the level of GDPs in their products. 3,4-Dideoxyglucosone-3-ene (3,4-DGE) has been identified as the most bioreactive GDP in PDFs.

Take care in how you store your PD fluids: actual temperature determines the balance between reactive and non-reactive GDPs.

Objective: During heat sterilization and during prolonged storage, glucose in peritoneal dialysis fluids (PDF) degrades to carbonyl compounds commonly known as glucose degradation products (GDPs). Of these, 3,4-dideoxyglucosone-3-ene (3,4-DGE) is the most cytotoxic. It is an intermediate in degradation between 3-deoxyglucosone (3-DG) and 5-hydroxymethyl-2-furaldehyde (5-HMF).

PD fluids contain high concentrations of cytotoxic GDPs directly after sterilization.

Objective: Glucose degradation products (GDPs) in peritoneal dialysis (PD) fluids are cytotoxic and affect the survival of the peritoneal membrane. One of the most reactive GDPs in PD fluids is 3,4-dideoxyglucosone-3-ene (3,4-DGE). 3,4-DGE has been reported as an intermediate between 3-deoxyglucosone (3-DG) and 5-hydroxymethyl furaldehyde (5-HMF) during degradation of glucose.

Temperature: the single most important factor for degradation of glucose fluids during storage.

Objective: Bioincompatible glucose degradation products (GDPs) develop during heat sterilization of peritoneal dialysis (PD) fluids. However, degradation may also take place during storage. Consequently, storage may add to the bioincompatibility caused by heat sterilization.

Acrylamide-induced effects on general and neurospecific cellular functions during exposure and recovery.

Basal cytotoxicity, morphological changes and alterations in cell physiological and neurochemical functions were studied in differentiated human neuroblastoma (SH-SY5Y) cells during exposure to acrylamide and during a subsequent recovery period after cessation of exposure. Acrylamide induced a 20% reduction in the number of neurites per cell at 0.21 mmol/L and 20% decrease in the protein synthesis rate at 0.

3,4-Dideoxyglucosone-3-ene (3,4-DGE): a cytotoxic glucose degradation product in fluids for peritoneal dialysis.

Background: Bioincompatible glucose degradation products (GDPs) in fluids for peritoneal dialysis (PD) develop during sterilization and storage. Their biological activity has successfully been monitored through the use of various in vitro methods but their molecular and chemical nature is less well understood. Many GDPs are highly reactive carbonyl compounds.

Glucose degradation products in peritoneal dialysis fluids: how they can be avoided.

Objectives: A patient on peritoneal dialysis (PD) uses 3-7 tons of PD fluid every year. The result is considerable stress on the peritoneal tissue. Aspects of PD fluids that have been considered responsible for bioincompatibility are low pH, high osmolality, high glucose and lactate concentrations, and the presence of glucose degradation products (GDPs).

Glucose degradation products in peritoneal dialysis fluids may have both local and systemic effects: a study of residual fluid and mesothelial cells.

Objective: When peritoneal dialysis (PD) fluids are heat sterilized, glucose is degraded to carbonyl compounds. These compounds are known to interfere with many cellular functions and to promote the formation of advanced glycation end-products. However, little is known about what actually happens with glucose degradation products (GDPs) after infusion into the peritoneal cavity.

Protection by glutathione of neutrophils against the toxic effects of peritoneal dialysis fluid.

The possibility of reducing the cytotoxic effect of heat-sterilized peritoneal dialysis (PD) fluid by addition of antioxidants/scavengers during incubation of titanium-adhering cells was investigated. Capillary blood from healthy donors was placed in drops on commercially available titanium pieces and incubated in a humidified chamber at 37 degrees C for 60min. After incubation the adherent polymorphonuclear leukocytes were immersed for 1-4h in PD-fluid, pH 7.

Degradation in peritoneal dialysis fluids may be avoided by using low pH and high glucose concentration.

Objective: When glucose is present in a medical fluid, the heat applied during sterilization leads to degradation. The glucose degradation products (GDPs) give rise to bioincompatible reactions in peritoneal dialysis patients. The extent of the degradation depends on a number of factors, such as heating time, temperature, pH, glucose concentration, and catalyzing substances.

Toxicity testing of polymer materials for dialysis equipment: reconsidering in vivo testing.

The rationale for preclinical testing of plastic materials for medical devices is the protection of patients from leachable toxic substances. A controversial and costly part of this testing is the use of animal in vivo procedures. The objective of the present study was to analyse the importance of in vivo tests in relation to the decision to approve or not to approve materials for use.

Neurite degeneration in differentiated human neuroblastoma cells.

We have studied neurite degeneration in differentiated human neuroblastoma (SH-SY5Y) cells. The axonopathy-inducing potency in vitro of caffeine, diazepam, methylmercury chloride (MeHg), triethyltin chloride (TET) and acrylamide (ACR) was elucidated. After 72 hours of exposure the neurite degeneration was determined (by morphological quantification) as well as the total protein content (general cytotoxicity).

Toxicity of 20 Chemicals from the MEIC Programme Determined by Growth Inhibition of L-929 Fibroblast-like Cells.

The Multicentre Evaluation of In vitro Cytotoxicity (MEIC) programme is an international project aimed at evaluating the relevance of in vitro tests in predicting human toxicity. We have screened 20 chemicals (MEIC codes 31-50) from the programme, by using a cytotoxicity test based on growth inhibition of the mouse fibroblast-like L-929 cell line. Inhibition of cell growth was determined by the neutral red uptake method, which is well established and is used for screening the cytotoxicity of chemicals and plastics for pharmaceuticals and medical devices.

Increased amounts of C3a and the terminal complement complex at high dialysis blood-flow: the relation with dialysis efficiency.

To estimate the influence of blood-flow on complement generation and the relation with dialysis efficacy (KT/V) 10 patients underwent cuprophan hemodialyses for 6 h using low (200 ml/min) or high (400 ml/min) blood-flow (n = 40). Dialysis with high blood-flow compared to low induced a more rapid drop in leukocyte count and a more pronounced leukocyte rebound. Net generation of C3a (microgram/min) was also larger at all 15 measuring points during high blood-flow dialysis and there was significantly larger total generation of C3a (after 3 h p < 0.

Are aldehydes in heat-sterilized peritoneal dialysis fluids toxic in vitro?

Objective: Chemical analysis of several brands of peritoneal dialysis fluids (PD fluids) has revealed the presence of 2-furaldehyde, 5-HMF (5-hydroxymethylfuraldehyde), acetaldehyde, formaldehyde, glyoxal, and methylglyoxal. The aim of this study was to investigate if the in vitro side effects caused by glucose degradation products, mainly formed during heat sterilization, are due to any of these recently identified aldehydes.

Design: Cell growth media or sterile filtered PD fluids were spiked with different concentrations of thealdehydes.

On complement net generation in fast hemodialysis: are high blood flow rates bioincompatible?

Arterial and venous concentrations of complement (C3a) and leukocyte count were determined in 17 patients during 201 hemodialysis sessions by 12 different treatment modes executed in random order using cuprophan, hemophan, or polyamide membranes with small or large membrane areas and high blood flow (Qb) (400 mL/min) for 2 hours or low Qb (200 mL/min) for 4 hours. With all membrane types, the number of leukocytes was significantly higher after 120 minutes of dialysis and by the end of treatment at high Qb compared with low Qb. C3a concentrations (microgram/mL) in the arterial and venous blood lines were significantly higher during cuprophan dialysis compared with hemophan and polyamide dialyses (P < 0.

Development of toxic degradation products during heat sterilization of glucose-containing fluids for peritoneal dialysis: influence of time and temperature.

Objective: Fluids for peritoneal dialysis (PD) cause cytotoxic reactions in many different in vitro systems. The low pH, the high osmolality of the fluids, and the glucose degradation products formed during heat sterilization have been considered responsible. In the present study, we investigate the influence of temperature and time during heat sterilization of PD fluids and glucose solutions on glucose degradation and cytotoxicity of the solutions.