In order to examine the role of myeloperoxidase (MPO) and neutrophil activation in the patho genesis of MPO-ANCA related necrotizing crescentic glomerulonephritis (GN), we investigated MPO release and superoxide anion (0^-₂) production from the neutrophils in MPO ANCA related GN. Plasma effect on MPO release from neutrophils was also studied in MPO-ANCA related GN. Neutrophils and plasma were obtained from 10 patients with MPO-ANCA-related GN (A), 10 patients with MPOANCA non related GN (B) and 10 healthy controls (C). MPO release and 0^-₂ production were assayed by using chemotactic factor, N-formyl-methionyl-leucyl-phenyalanine (FMLP) and cytochalasin B (CB). In MPO-ANCA related GN, MPO release and 0^-₂ production were significantly higher than in the other groups. [MPO release (%) A: 43.02±18.33, B: 33.26±11.58 C: 19.73±8.38, sensitivity to FMLP (%) A: 894.56±381.96, B: 512.86±314.91, C: 301.12plusmn;139.8, 0^-₂ production (nmoles/min/ 106cells) A:13.06±5.28, B: 3.57±2.02, C: 2.83±1.16] Furthermore, MPO release, sensitivity to FMLP and 0^-₂ production were shown to increase in parallel with clinical disease activity. Plasma from MPO-ANCA related GN increased sensitivity to FMLP in neutrophils obtained from healthy controls [plasma concentration 1 %, A: 311.5±110.3, B: 227.2±101.4, C: 215.5±93.7], and plasma from MPO-ANCA related GN suppressed %MPO release from neutrophils with MPO-ANCA related GN [plasma concentration 0.1%, A: 11.56±6.17, C: 15.51±8.01]. It was concluded that in patients with MPO-ANCA related GN, large amounts of MPO can be easily released from activated neutrophils and this might be influenced by some stimulating and suppressing factors contained in the plasma.

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Ultrafiltration failure has been one of the major causes of drop out from CAPD treatment. The present study was designed to develop an ultrafiltration failure model in the rat and to assess whether various agents could prevent a decrease in ultrafiltration capacity in this rat model. Peritoneal hyperpermeability was induced by repeated intraperitoneal injection of 15m1 of 4.25% dextrose dialysate for 7 days. Some of the rats received agents, such as phosphatidylcholine, chondroitin sulfate, siliac acid, heparan sulfate, keratan sulfate, sodium sulfate, sodium phosphate, and heparin sodium, simultaneously administered with 4.25 % dextrose dialysate for the same duration. Ultrafiltration volume, D₄/D₀ ratio of glucose and peritoneal net fluid absorption were evaluated by 4-hour dwelling of 30ml of 2.5% dextrose dialysate. Sodium phosphate and heparan sulfate prevented peritoneal hyperpermeability due to repeated injection of hypertonic dialysate. Sodium phosphate, sodium sulfate, heparin and heparan sulfate suppressed peritoneal net fluid absorption, resulting in an increase in ultrafiltration. These findings may be applicable to CAPD patients with ultrafiltration loss.

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Urinary excretion and release of prostaglandins (PG) from isolated glomeruli and renal papilla of deoxycorticosterone acetate (DOCA)-treated rats fed with a normal salt (0.6%NaCI) diet and a high salt (4%NaCI) diet were determined. Mean blood pressure was significantly higher in the high salt diet group than in the normal salt diet group (146.2±2.3 vs 118.6± 1.9mmHg, p<0.01) . Urinary excretion of thromboxane (Tx) B₂, stable metabolite of Tx A₂, and 6-keto PG-F_1α, a stable metabo lite of prostacyclin, increased significantly in the high salt diet group compared to the values of the normal salt diet group. The release of Tx B₂, 6-keto-PG F_1α and PG E₂ from isolated glomeruli of the high salt diet group increased significantly by 104%, 55%, and 74% compared to those of the normal salt diet group, respectively. Release of 6-keto-PG F_1α from renal papilla of the high salt diet group decreased significantly, but there were no intergroup differences in the release of PG E₂ and Tx B₂. Stepwise multiple linear regression analysis showed that the significant contributory factors underly ing the mean blood pressure were urinary excretion of Na (F=14.187, p<0.01) and release of Tx B₂ from isolated glomeruli (F=4.135, p<0.05). These findings suggest that the manifestation of Txsynthesis in renal glomeruli has a predominant role in the salt sensitive pressor response of DOCA salt hypertension in rats.

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It is known that Helicobacter pylori (H.pylori) plays an important role in gastritis and peptic ulcer disease in the general population. Although upper gastrointestinal mucosal lesions have been one of the most common complications in patients with chronic renal failure, quite few reports are available regarding the prevalance of H. pylori and its influence on the upper gastro-intestinal tract. The present study was conducted to examine whether H, pylori is involved in the pathogenesis of upper gastroin testinal mucosal lesions in dialysis patients. The subjects consisted of 43 dialysis patients with upper gastro-intestinal tract symptoms. Thirty-four patients without any known kidney disease were used as controls. Gastric mucosa and gastric juice were obtained endoscopically. For the determination of H. pylori, culture of biopsy specimens from the gastric mucosa and histopathological examination with hematoxylin-eosin stain were used. Concentrations of serum gastrin and gastric juice ammonia were also measured. H. pylori was observed in 53.5% of the dialysis group and 64.0% of the controls. Gastro-duodenal lesions in H. pylori-positive dialysis patients included atrophic gastritis, superficial gastritis, erosive gastritis, and gastric ulcer. In the dialysis group, ammonia concentrations in the gastric juice were higher in patients with H. pylori than in those without H. pylori (489.1±35.8μg /ml vs 67.0±19.2μg/ml, p<0.001). The former value was also higher than that seen in the H. pylori positive controls (152.4±18.7μg/ml, p<0.01). Serum levels of gastrin were significantly higher in patients with H. pylori than in patients without H, pylori both in the dialysis and the control group. There was a positive correlation between the concentrations of gastric juice ammonia and serum gastrin in the H. pylori-positive patients. Marked infiltrations of polymorphonuclear cells in the lamina propria were noted in the patients with H. pylori, while few inflammatory cells were present in those without H. pylori. These observations suggest that elevated concentrations of serum gastrin and gastric juice ammonia are attributable, at least in part, to H, pylori. In conclusion, H. pylori may play a role in the pathogenesis of upper gastrointestinal mucosal lesions, at least for gastritis and gastric ulcer, in dialysis patients.

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we have invented a new dipstick (protein titrator tape) for measuring the volume of protein excreted in the 24-hour urine. The principle of the method is based on the protein error of indicators with the modification of a conventional dipstick test. The dipstick consists of two thick filter papers, containing differently adjusted pH indicators of tetrabromphenol blue, making it possible to detect a wide range of protein concentrations in the urine using a standard color chart that includes twenty color blocks. Two hundred and ninety outpatients had their urine samples assessed with this method as well as with the pyrogallol red test as a comparative study for quantitative measurement of protein concentrations. The new-type dipstick method exhibited good correlation with the results of the pyrogallol red test, especially in the range of protein concentrations from 50 mg/dl to 400 mg/dl, showing the linear equation of “y (pyrogallol red) =10.5 + 0.99× (Dipstick) (r = 0.9 P<0.01) ”. Although there was good correlation with the pyrogallol red test at higher concentrations from 400 mg/dl to 1, 000 mg/dl, the dipstick method tended to exhibit lower concentrations than those indi cated by the counterpart method. The rate of consistency between observers was quite high. This new-type dipstick method will offer a reliable method for patients or their family to assess their protein excretion in the urine every 24 hours at home using a portable urine sampling device.

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A 53-year-old man was admitted for treatment of nephrotic syndrome due to membranous nephropathy. Since he did not improve with prednisolone alone, cyclophosphamide was administered concomitantly. However, this induced severe interstitial pneumonitis, which was not cured by discon tinuation of the drug, but disappeared completely with six episodes of methylprednisolone pulse therapy. The incidence of cyclophosphamide-induced interstitial pneumonitis is low, but the mortality is high. Since cyclophosphamide is often used for the treatment of nephrotic syndrome, attention should be focused on the incidence of interstitial pneumonitis . Discontinuation of cyclophosphamide and intensive therapy are required when it occurs.

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A previously well 66-year-old woman was admitted to our hospital because of severe abdominal pain, oliguria, jaundice and hemoglobinuria. At admission, the following values were obtained: redblood cell count 261x 10⁴/mm³, serum creatinine 2.8mg/ 100ml, total bilirubin 8.0mg/ml, indirect bilirubin 5.7mg/ 100ml, LDH 13886 WU, negative direct and indirect Coomb's test and peripheral blood smear showing schistocytosis. She was diagnosed as hemolytic uremic syndrome and was successfully treated with plasma infusion, plasma exchange and hemodialysis. The results of the tests for verotoxin titer of E. coli 0157: H7 and circulating anticoagulant were positive. The test result for anticoagulant eventually became negative during her clinical course. In this case, circulating antico agulant might have contributed to the pathogenesis of hemolytic uremic syndrome.

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