[Clinical and biochemical analysis of ligature-induced periodontitis in rats].

The most common experimental model of periodontitis is a "ligature" model. However due to the complexity connected with performing on rats, modification of existing model is proposed, which differs by fixture of cotton ligature around the central incisor and not around the second molar. The purpose of research - a comparative evaluation of "peroxide" and modified by us, "ligature" models of periodontitis in rats. 2 series of experiments on 36 white Wistar rats were conducted. The animals were divided into two groups: intact rats (control) and rats with a "peroxide" model of periodontitis, which was reproduced by the addition to the diet of rats overoxidized sunflower oil (5% by weight of the feed), daily, for 45 days. "Ligature" model in rats was reproduced by applying a cotton ligature on the central incisor of the upper jaw for 14 days. Elastase activity, malondialdehyde content and catalase activity in the gums and in the blood serum was measured by biochemical methods. The degree of atrophy of the alveolar bone of the mandible was determined by morphometric method. It is found that in both models of periodontitis in rats, changes in the periodontal tissues and in the organism as a whole, is common for periodontal disease in humans. Clinically apparent inflammation of the periodontal tissues is observed, metabolic disorders in the gums, change of biochemical parameters in serum and progressive decline in the alveolar bone are determined. A comparative analysis of the two models showed that the modified "ligature" model of periodontitis in rats has several advantages over the "peroxide" model: shorter term of modeling, more pronounced clinical inflammation of periodontal tissues and faster resorption of alveolar bone.

Proteolytic inactivation of dog lung surfactant-associated proteins by neutrophil elastase.

The adsorption of pulmonary surfactant to an air/fluid interface is influenced by calcium-dependent interactions between its lipid and protein components. The latter include a glycoprotein of 28-36 kDa (SP-A) and two smaller hydrophobic proteins of 5-8 kDa (SP-B, SP-C). Neutrophil elastase and other proteolytic enzymes found in the alveolar washings in a variety of acute lung injuries may cleave the protein components of lung surfactant. To examine the hypothesis that free airspace elastolytic activity may thereby impair surfactant function, we analyzed the effect of neutrophil elastase on surfactant activity in vitro. The adsorption characteristics of dog surfactant and of complexes reassembled from purified surfactant components were examined after incubations with active or heat-inactivated neutrophil elastase. Surfactant preincubated with the active enzyme showed a marked concentration-dependent slowing of adsorption associated with proteolytic cleavage of SP-A. To determine whether elastase also decreases surface activity by affecting the hydrophobic proteins SP-B and SP-C, we studied the effect of incubating elastase with liposomes prepared from surfactant lipid fractions which contain SP-B and SP-C. The addition of intact SP-A to these liposomes incubated with inactive enzyme immediately enhanced adsorption speed. This enhancement was greatly attenuated in liposomes treated with active elastase, suggesting that one or both of the hydrophobic surfactant proteins had been affected by elastase. We conclude that proteolytic cleavage of surfactant proteins reduces adsorption speed in vitro and may disturb surfactant function in vivo.

Consumption of complement and activation of human neutrophils by an artificial immune complex: polyacrylic acid-IgG-polymer.

An artificial immune complex consisting of IgG covalently bound to polyacrylic acid (PAIGP) was prepared and investigated for its influence on a number of immunological reactions attributed to natural immune complexes. PAIGP consumed complement in a fast reaction. Complement consumption was complete after 10 min of incubation of guinea-pig serum with PAIGP. The concentration of PAIGP for 50% consumption was 2.3 micrograms/ml. PAIGP induced a chemiluminescence response in human peripheral polymorphonuclear leukocytes. This response was elicited in the absence and presence of serum and in whole blood. The response was maximal for leukocytes in the absence of serum and rather low in whole blood. The induction of chemiluminescence by PAIGP was inhibited by monoclonal antibodies to one of the Fc receptors of leukocytes (anti-Leu 11B), while unrelated antibodies had no influence on the chemiluminescence induced by PAIGP. PAIGP also stimulated the production of superoxide anion by polymorphonuclear leukocytes. The efficacy of PAIGP in stimulation of superoxide production was comparable to phorbol myristate acetate (PMA) and opsonized zymosan. PAIGP induced the discharge of elastase, a constituent of the azurophile granules of PMN leukocytes. Here, PAIGP was a rather weak stimulus compared to opsonized zymosan. PMA proved unable to induce elastase release. Thus, PAIGP induced a number of biological reactions usually brought about by naturally occurring antigen antibody complexes.

Inactivation of tissue inhibitor of metalloproteinases by neutrophil elastase and other serine proteinases.

Tissue inhibitor of metalloproteinases (TIMP) from cultured bovine dental pulp inhibits human rheumatoid synovial matrix metalloproteinase 3 (MMP-3) with a stoichiometry of 1:1 on a molar basis. Among the serine proteinases examined, human neutrophil elastase, trypsin and alpha-chymotrypsin destroyed the inhibitory activity of TIMP against MMP-3 by degrading the inhibitor molecule into small fragments. In contrast, the inhibitory activity of TIMP was not significantly reduced by the actions of cathepsin G, pancreatic elastase and plasmin. These data indicate that neutrophils which infiltrate tissues in various inflammatory conditions may play an important role in regulating TIMP activity in vivo through the action of neutrophil elastase.

Phosphorylcholine or heparin coating for pediatric extracorporeal circulation causes similar biologic effects in neonates and infants.

OBJECTIVE: Cardiac surgery for complex congenital malformations with use of extracorporeal circulation predisposes to an excessive systemic inflammatory response and a consecutive capillary leak syndrome. In a prospective randomized study the influence of 2 oxygenators especially designed for pediatric use on inflammatory markers and clinical outcome was investigated. METHODS: Forty neonates and infants (body surface area, <0.36 m(2)) undergoing cardiac surgery with extracorporeal circulation were randomized into one of 3 groups: in the first group (n = 14) the Medtronic Minimax Oxygenator and in the second group (n = 12) the Dideco Lilliput 1 Oxygenator, both with a 750-mL priming volume, were used. In the third group the Dideco Lilliput 1 Oxygenator was filled with a reduced priming volume of 450 mL. Parameters of interest for evaluation of a systemic inflammatory response after extracorporeal circulation were interleukin 6, tumor necrosis factor alpha, neutrophil elastase, complement C3, and free hemoglobin. In addition, erythrocyte, leukocyte, and thrombocyte counts and hemoglobin and C-reactive protein values were determined at different measurement points before, during, and after the operation. RESULTS: In all 3 groups peak values for tumor necrosis factor alpha were observed during the operation, whereas interleukin 6, elastase, and free hemoglobin values peaked in the first 4 hours. The highest values for leukocytes and C-reactive protein were obtained between 24 and 72 hours after the operation. Erythrocyte and thrombocyte counts, as well as hemoglobin values, were lowest at extracorporeal circulation onset, normalizing under substitution in the first 4 hours after the operation. By using the Lilliput/750 oxygenator, higher interleukin 6 values 1 and 4 hours after the operation and higher tumor necrosis factor alpha values during and 1 hour after the operation could be observed compared with results with the Minimax and Lilliput/450 oxygenators. In spite of our randomization protocol, patients in the Lilliput/750 group were significantly smaller and younger than those in the Minimax group. However, the statistical analysis showed no correlation between age and interleukin 6 or tumor necrosis factor alpha values, but it did show a correlation between younger age and the occurrence of capillary leak syndrome. Accordingly, the number of children with clinically complicated course (capillary leak, longer duration of catecholamine therapy, and ventilation) was higher in the Lilliput/750 group than in the Minimax group. CONCLUSION: By using an adequate priming volume, the systemic inflammatory response is similar after use of the Dideco Lilliput 1 Oxygenator and the Medtronic Minimax Oxygenator. Tip-to-tip surface coating of the extracorporeal circulation with either heparin or phosphorylcholine seems to have similar biologic effects in neonates and infants undergoing cardiac surgery.

Change of elastase and cathepsin G content in polymorphonuclear leukocytes during hemodialysis.

Previous studies have demonstrated an increment of polymorphonuclear (PMN) elastase plasma levels during hemodialysis, suggesting release of this proteinase during dialysis treatment. In order to gain further evidence that proteinases are liberated from PMN leukocytes during dialysis both plasma levels of PMN elastase and the content of elastase and cathepsin G in neutrophils were determined during 3 hours of hemodialysis with cellulosic membranes (Cuprophan) in 10 patients. In blood smears, obtained at different times during dialysis, neutrophils were classified into 3 groups according to their proteinase content. Thus, group I neutrophils contained low, group II moderate, and group III leukocytes contained high amounts of both proteinases. With regard to their elastase content, prior to the onset of dialysis, 6% of the circulating PMN leukocytes were classified as fraction I, 58% as fraction II, and 36% as fraction III neutrophils. After 15 minutes of dialysis, at the nadir of leukopenia, all fractions of PMN leukocytes were significantly reduced (fraction I: -9%, fraction II: -60%, and fraction III: -83%) as compared to initial values. 30 minutes into hemodialysis, there was a significant increase in fraction I (+ 78%), whereas fraction II (-28%) and fraction III (-70%) remained diminished. At 180 times of hemodialysis the increment of fraction I neutrophils was even more pronounced (+ 187%), fraction II was also increased (+ 16%), and fraction III neutrophils had almost reached initial values. The cathepsin G content of PMN leukocytes displayed a rather similar pattern during dialysis. As to plasma levels of PMN elastase, there was a steady and significant increase from baseline values of 107.3 +/- 11.5 ng/ml up to 388.1 +/- 51.6 ng/ml after 3 hours of hemodialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Improvement of dialyzer compatibility by reduction of membrane surface area.

The present study was devised to investigate, whether reduction of membrane surface area would contribute to enhanced dialyzer membrane compatibility. Therefore, 10 hemodialysis patients were dialyzed with three different cuprophan dialyzers, displaying membrane surface areas of 0.9 m2, 1.2 m2, and 1.8 m2. As an index of biocompatibility release of granulocyte elastase and secretion of granulocyte lactoferrin were determined by enzyme-linked immunoassays. With the three cuprophan membranes, marked leukopenia occurred 15 min after the start of hemodialysis, without significant distinction between the different membranes. On the other hand, the release of leukocyte elastase was strictly dependent on the membrane surface area. Thus, at the end of dialysis, plasma levels of elastase were as follows: 0.9 m2: 255 +/- 51; 1.2 m2: 356 +/- 65; 1.8 m2: 471 +/- 56 ng/ml. The magnitude of secretion of leukocytic lactoferrin was also dependent on membrane surface area. Therefore, the increment during dialysis was 300% with the 1.2 m2 membrane compared to 650% using a 1.8 m2 dialyzer. Based upon these data, we concluded that, using measurements of granulocyte degranulation as an index of biocompatibility, reduction of membrane area resulted in a marked improvement of membrane compatibility.

Reduced complement activation during cardiopulmonary bypass does not affect the postoperative acute phase response.

OBJECTIVE: In the present study the relationship was evaluated between perioperative inflammation and the postoperative acute phase response in patients undergoing elective coronary artery bypass grafting (CABG) assisted by cardiopulmonary bypass (CPB). CPB circuits contained either non-coated- (UMS), Carmeda- (BPS) or Trillium-coated oxygenators (BAS). METHODS: Prospectively, 71 CABG patients were randomly allocated to one of the oxygenator groups (UMS: n=25, BPS: n=25 and BAS: n=21). Terminal complement complexes (TCC) and elastase were determined in plasma samples collected before, during and after bypass. Secretory phospholipase A2 (sPLA2) and C-reactive protein (CRP) were determined before and after bypass. RESULTS: Demographic, CPB and clinical outcome data were similar for the three groups. TCC and elastase increased during CPB, and decreased thereafter. Significant differences between the groups were present in the levels of TCC at the end of CPB (P=0.002) and at the first (P=0.012) and second (P<0.001) postoperative days, the BPS and BAS groups having reduced levels of TCC compared to the UMS group. Also elastase concentrations differed significantly between the groups at the end of CPB (P<0.001). The postoperative sPLA2 and CRP levels increased in all three groups on the first and second postoperative days, but no significant differences were present between the groups. CONCLUSIONS: Material-induced reduction of the inflammatory response during CPB does not affect the postoperative acute phase response. Thus, in CABG patients this response seems relatively unaffected by the composition and/or biocompatibility of the modern CPB circuit and rather to be evoked by surgical trauma, anesthetics and organ perfusion.

Plasma levels of bactericidal/permeability-increasing protein (BPI) and lipopolysaccharide-binding protein (LBP) during hemodialysis.

Several proteins modify the biological response to lipopolysaccharide (LPS). Both bactericidal/permeability-increasing factor (BPI), a protein stored in neutrophils, and the acute phase protein LPS-binding protein (LBP) bind to LPS; however, BPI inhibits while LBP enhances binding of LPS to leukocytes and subsequent induction of cytokines. We investigated plasma levels of BPI, LBP, elastase and C5a before, during and after hemodialysis (HD). Six patients were dialysed with Cuprophane (Cup) and polysulfone (PS) low-flux dialyzers on two consecutive HD sessions. There was a significant, 10.9 +/- 2.8-fold increase in BPI after 4-hour HD compared to predialysis and a 4.4 +/- 1.6-fold increase in elastase after 4-hour HD using Cup. Plasma levels of BPI and elastase decreased rapidly after the dialysis session. HD with PS resulted in a smaller, but still significant rise in BPI (3.7 +/- 1.6-fold at 4 hours) and elastase (1.69 +/- 0.2-fold at 4 hours). Levels for BPI and elastase were similar in the arterial and venous blood lines of the dialyzer. Plasma levels of LBP did not change during or after the HD session. These data indicate that BPI, but not LBP is released during HD with Cup and to a lesser extent with PS. Activation of neutrophils and release of BPI during HD may influence the biological response to bacterial products possibly introduced during HD.

Effect of gamma radiation versus ethylene oxide sterilization of dialyzers and blood lines on plasma levels of granulocyte elastase in hemodialyzed patients.

The effect of gamma versus ethylene oxide sterilization of different dialyzers (polyacrylonitrile, cuprophan) and blood lines on plasma levels of granulocyte elastase and of lysozyme during hemodialysis was investigated in 17 chronically uremic patients. Plasma levels of granulocyte elastase increased during hemodialysis but significantly less in the presence of polyacrylonitrile compared with cuprophan membranes. In contrast, enhanced lysozyme plasma levels decreased during dialysis using the polyacrylonitrile dialyzer to values of healthy controls and remained unchanged using the cuprophan dialyzer. Both effects were not influenced by the way of sterilization. We conclude that granulocyte activation during hemodialysis occurs independently of the sterilization procedure of dialyzers and blood lines in patients showing no clinical signs of hypersensitivity.

Different complement and granulocyte activation in patients dialyzed with PMMA dialyzers.

Plasma C3a and C5a levels as well as plasma levels of granulocyte lactoferrin, granulocyte myeloperoxidase and granulocyte elastase in complex with alpha 1-proteinase inhibitor (E-alpha 1PI) were investigated in 10 patients (52.7 +/- 5.9 years) undergoing maintenance hemodialysis (39.4 +/- 12.4 months) with hollow fiber dialyzers made from polymethylmethacrylate. Plasma levels of lactoferrin increased from 166.5 +/- 28.5 to 712.5 +/- 165.9 ng/ml, myeloperoxidase from 59.0 +/- 15.3 to 210.5 +/- 33.9 ng/ml and E-alpha 1PI from 114.2 +/- 18.1 to 681.8 +/- 102.6 ng/ml during dialysis. In contrast, plasma C3a levels rose from 179.8 +/- 33.6 to maximal 276.2 +/- 45.4 ng/ml and C5a from 55.7 +/- 8.1 to maximal 101.1 +/- 14.8 ng/ml. Our data indicate that degranulation of granulocytes occurs during dialysis despite only little complement activation and mild initial granulocytopenia.

Quantitative analysis of immunoglobulins and inflammatory factors in human pulpal blood from exposed pulps.

The levels of immunoglobulins (IgG, IgA, and IgM) and inflammatory factors (elastase, prostaglandin E2, interleukin-1 alpha, interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha) in the blood of human dental pulp were quantified, using enzyme-linked immunosorbent assays. The pulpal blood samples were obtained with nylon fiber pellets from normal and inflamed dental pulp at pulp sites exposed on pulpectomy. Statistically significant differences between normal and inflamed pulp were found in the levels of IgG (p < 0.01), IgA (p < 0.05), IgM (p < 0.01), elastase (p < 0.05), and prostaglandin E2 (p < 0.01). These findings indicate that these factors play an important role in the pathogenesis of pulpal disease, and the sampling methods used in this study are useful for examination of pulpal inflammation.

Blood flow dependent granulocyte activation in membranes with and without complement activation.

Synthetic membranes activate the complement system to some degree but also clear complement fragments from the circulation by adsorption and/or filtration and dialysis, PAN and PMMA even lower preexisting plasma levels of C3a. Activation of granulocytes measured as elastase release does occur with all membranes and might be due to complement activation. However, in synthetic membranes no correlation exists between levels of complement fragment C3a and elastase release. Instead, even when PMMA membrane lowered preexisting plasma levels of the C3a below baseline, activation of granulocytes to a similar degree as known from cuprophane membranes was observed. This activation did occur with blood flow of 200 ml/min during recirculation, but not without blood flow during incubation of membrane material. We conclude that granulocyte activation in synthetic membranes does not require an activated complement system, but may be a blood flow dependent phenomenon.

Patterns of blood response during cardiopulmonary bypass.

Monitoring of cardiopulmonary bypass (CPB) in terms of alterations to the concentrations of selected blood constituents leads to contrasting patterns of response. This has been verified by determining the influence of CPB on the activation of fibrinolysis, complement, leucocytes and the contact phase of coagulation. Fibrinolytic activity was determined by fibrin degradation products (X-FDP's), complement activation by C3a and C5a, leucocyte activation by granulocyte elastase and contact activation by factor XII-like activity (FXIIA). Five patients undergoing elective coronary artery surgery using a bubble oxygenator and pulsatile perfusion were studied. X-FDP's rose gradually during CPB and remained elevated. Similar patterns were observed for elastase and FXIIA. In contrast, C3a rose sharply with peak values at 1 1/2-2h of bypass while C5a did not show significant changes during bypass. The data obtained have enabled the establishment of response patterns for parameters in CPB which will provide information relevant to the clinical application of biomaterials.

Influence of haemodialysis membranes on the release of granulocyte elastase.

The advantages of multiparameter assessment in the evaluation of the blood compatibility of biomaterials underline the importance of investigating possible relevant parameters. In this respect, a study has been made of granulocyte elastase to establish the influence of haemodialysis membranes on the release of this serine proteinase. Plasma levels of granulocyte elastase were determined as a complex with its natural inhibiter, alpha 1-proteinase. This elastase - alpha 1 proteinase (E- alpha 1 Pi) inhibitor complex was measured by a highly sensitive enzyme-linked immunoassay. The membranes evaluated were Cuprophan (15-11, Travenol) and polysulphone (F40, Fresenius). Samples were taken from patients undergoing maintenance haemodialysis, before the start of dialysis, after 15 and 90 minutes and again at the end of dialysis (4 h). This investigation clearly demonstrates the different response of the dialysers, and on correcting for surface area, the end-dialysis level of E-alpha 1 Pi remained significantly greater for the Cuprophan membrane. The results support the view that the release of granulocyte elastase is a relevant parameter for inclusion in membrane compatibility assessment.

In vitro and in vivo biocompatibility of substituted cellulose and synthetic membranes.

Regenerated cellulosic membranes are held as bioincompatible due to their high complement - and leukopenia - inducing properties. Adherence of polymorphonuclear neutrophils and monocyte purified from normal human blood to the three membranes were evaluated in an in vitro recirculation circuit in the presence or absence of fresh, autologous plasma after recirculation in an in vitro circuit using minimodules with each of the three membranes. In in vivo studies, 9 patients were treated with conventional haemodialysis for 2 weeks with each membrane and 1 week for wash-out using haemodialysers with the following surface: 1.95 m2 for benzyl-cellulose, 1.8 m2 for acetate-cellulose and low-flux polysulfone. Measurement of leukopenia, plasma C3a des Arg and elastase-alpha1 proteinase inhibitor complex levels as well as urea, creatinine, phosphate and uric acid clearances was performed. Plasma-free neutrophils adhered maximally to acetate-cellulose (65% remaining in the circulation), while there was no significant difference between low-flux polysulfone and benzyl-cellulose (80% circulating neutrophils, at 15 min, p<0.001 vs acetate cellulose). In the presence of fresh plasma, as source of complement, the differences between acetate cellulose vs polysulfone and benzyl-cellulose were even more evident, suggesting the role of complement-activated products in neutrophil adherence. A similar trend was observed for monocyte adherence with the three membranes in the absence or presence of plasma. In vivo studies showed that the nadir of leukopenia was at 15 and 30 min with acetate-cellulose (79%) and benzyl-cellulose (50%) (p<0.05 acetate- vs benzyl-cellulose) and at 15 min with polysulfone (24%) (p<0.01 vs acetate- and benzyl-cellulose). Plasma C3a des Arg levels arose to 2037 +/- 120 ng/ml, 1216 + 434 ng/ml and 46 +/- 55 ng/ml with acetate-, benzyl-cellulose and polysulfone, respectively. No pre- vs post-dialysis increase in the intracellular content of TNF-alpha was detected with any of three membranes. Clearance values of urea, creatinine and uric acid were superimposable for all the three membranes. However, benzyl cellulose had a significantly higher clearance for phosphorus (normalized for surface area) (p<0.01 vs acetate-cellulose, 0.001 vs polysulfone). These results implicate that synthetic modification of the cellulose polymer as for the benzyl-cellulose significantly reduces the in vitro adherence, delays the in vivo activation of "classic" biocompatibility parameters and notably improves the removal of inorganic phosphorus.

Effect of dialyser composition and reuse on neutrophil count and elastase alpha-1 proteinase inhibitor complex formation.

To assess the inter-relationship of leucopenia and PMN elastase release we undertook a prospective crossover study of 6 patients dialysed with new and reused cuprophane, cellulose acetate and polysulfone membranes. Serial blood samples were analysed for PMN count, and elastase-alpha 1-proteinase inhibitor complex (E alpha 1PI) concentrations. After 15 min dialysis with new membranes median PMN counts fell by 72.2%, 25.3% and 22.1% with cuprophane, cellulose and polysulfone, respectively. With reuse the decreases were reduced to 6.4%, 8% and 13.6%. All membranes produced a gradual increase of E alpha 1PI. Median E alpha 1PI accumulation rates (ng ml-1 min-1) with new membranes were 175, 169 and 187 for cuprophane, cellulose acetate and polysulfone, respectively. With reuse of cuphrophane and cellulose acetate these rates fell to 99 and 109 (p less than 0.05 and p less than 0.05, respectively), however, with polysulfone it remained unchanged at 180 ng ml-1 min-1. This study highlights differences between two aspects of the neutrophil response to haemodialysis, and demonstrates that extrapolation from individual parameters to conclusions concerning biocompatibility may be inappropriate.

Clinical evaluation of a new high-flux cellulose acetate membrane.

One major goal of dialysis therapy has become the removal of beta 2-microglobulin (beta 2-m). The interdialytic elimination of beta 2-m was studied using a newly developed high-flux cellulose acetate (CA) membrane. The results show that high-flux CA dialyzers offer better biocompatibility than classical Cuprophan or high-flux Cuprophan devices, with regard to leukopenia, C3a desarg generation, and elastase release from polymorphonuclear (PMN) leukocytes. Compared to high-flux CA membranes, high-flux PMMA membranes induce less C3a desarg formation but comparable leukopenia. High-flux PMMA membranes, however cause greater leukocyte stimulation than CA as demonstrated by more PMN elastase release during hemodialysis. Using high-flux CA or high-flux PMMA membranes, serum beta 2-m levels decreased 32% during dialysis. Serum beta 2-m dropped 10% with high-flux Cuprophan membranes, but remained unchanged with conventional Cuprophan dialyzers. Sieving coefficients for beta 2-microglobulin (beta 2-m) were virtually zero with classical Cuprophan and 0.66 with high-flux cellulose acetate membranes. High-flux membranes made of Cuprophan and PMMA gave coefficients of 0.25 and 0.45, respectively. This indicates the high removal capacity of the new CA-membrane for substances with high molecular weight. This high-flux CA membrane thus appears to combine a good degree of biocompatibility with a high capacity for beta 2-m removal.

Ethylene-oxide and steam-sterilised polysulfone membrane in dialysis patients with eosinophilia.

Eosinophilia and some acute dialysis side-effects, such as itching, flushing and bronchospasm, are often associated with the presence of ethylene oxide (ETO) as dialyzer sterilizing agent. This study evaluated the effects of two different polysulfone (PS) hollow-fiber dialysers sterilized with ETO and steam in 31 chronic dialysis patients with eosinophilia. Clinical symptoms, metabolic and biochemical parameters, complement (C3a and C5a) activation and production were evaluated in each patient dialysed for two months at a time with Cuprophan dialyser, ETO-PS dialyser and steam-PS dialyser. The steam-sterilizer agent does not alter the purifying capacity of the PS membrane which maintains its superiority over Cuprophan in terms of biocompatibility. Using steam-PS, intradialytic eosinophil kinetics seems to improve. In some patients with high serum levels of ETO-specific IgE these levels tend to diminish. Generic intradialytic symptoms do not differ between the two sterilization methods, although some hypersensitivity symptoms during the first dialysis hour are considerably lower in some patients when steam-sterilized PS is used.

[Determination of elastase 1 in plasma or serum by latex turbidometric immunoassay with automatic analyzer].

We developed a latex turbidometric immunoassay(LTIA) for elastase 1. The precisions were 1.0-2.8% intra-run and 1.2-2.9% inter-day. The dilution test showed good linearity between 80-4000 ng/dl. There was interference by bilirubin, hemoglobin, lipemia or rheumatoid factor. Serum and plasma elastase 1 measured by LTIA(y) showed significant correlations with those by RIA(x) (serum: y = 0.98x--18, r = 0.980, n = 64, plasma: y = 0.96x--19, r = 0.976, n = 61). It was confirmed that the values were elevated in patients with pancreatic disease compared to the normal level. These results demonstrate that the determination of elastase 1 in plasma or serum by this method is useful, simple and time-saving, when compared with that by RIA.