ISSN:0250-8095    

DOI:10.1159/000168167

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Peritoneal dialysate immunoglobin (Ig)G concentrations were measured in 120 continuous ambulatory peritoneal diaysis (CAPD) patients evaluated at four dialysis centers in different countries to assess the normal range for dialysate IgG and to investigate the relationships of this protein levels with peritoneal episodes, For 65 of these patients, plasma IgG levels were determined, and IgG clearances were calculated. The mean dialysate concentration of IgG was 6.9 ± 4.2 mg/dl, and there was no difference between men and women or between patients who had or had not previously undergone hemodialysis. Dialysate IgG concentrations were significantly related to residual renal creatinine clearance and negatively correlated with dialysate volume, plasma albumin and total protein. There were no significant correlations between IgG levels in the dialysate and age, protein losses in the dialysate, time on CAPD or time from the last peritonitis episode. Plasma and dialysate IgG were unrelated to the incidence of peritonitis, statistical analysis being performed with different methods. These results suggest that IgG levels in the dialysate or plasma are not a major factor in the prevention of CAPD peritonitis

ISSN:0250-8095    

DOI:10.1159/000168168

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Although angiotensin-converting enzyme (ACE) inhibitors may lower urinary protein excretion, it is not known whether these agents can completely eliminate microalbuminuria. This study examined whether the ACE inhibitor, enalapril, can abolish low levels of microalbuminuria in diabetic patients. Six men with adult-onset, insulin-dependent diabetes mellitus, most of whom had low levels of microalbuminuria, were studied in a clinical research center, where they ate a controlled diet and performed regulated exercises daily. After 2 weeks of baseline measurements, the patients received 5–15 mg/day of enalapril for 4 weeks. They were then monitored for 2 more weeks without enalapril. Urinary albumin excretion (UAE) fell in each patient with enalapril treatment and was within the normal range at some time during enalapril treatment in 5 of 6 patients. After stopping enalapril, UAE rose. UAE was 53.6 ± 20.7 (SEM), 31.5 ± 8.9 and 39.4 ± 8.0 mg/24 h during the baseline, enalapril and postenalapril periods, respectively (baseline vs. enalapril, p < 0.02; postenalapril vs. enalapril, p < 0.01). The magnitude of fall in UAE correlated with the baseline UAE (r = 0.90). During enalapril treatment, renal plasma flow and GFR did not change, although blood pressure fell slightly. These data suggest that enalapril can reduce or abolish UAE in diabetic patients with microalbuminuria. Whether long-term treatment with enalapril will continue to suppress microalbuminuria and prevent progressive diabetic nephropathy remains to be determ

ISSN:0250-8095    

DOI:10.1159/000168169

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Abnormalities of tubular membrane structure and composition have been proposed as the primary defect in nephronophthisis (NEF). In order to characterize the protein composition of tubular cells in NEF, in vitro methods were developed to culture and propagate tubular cells obtained from biopsy fragments. Accordingly, microdissected cortical slices (1X3 mm) were first digested with collagenase and DNAse and then grown in RPMI medium supplemented with 10% NU serum and conditioned serum deriving from 3T3 cultures. At confluence, cultured cells from NEF showed characteristics which were typical of normal tubules, i.e. presence of cytokeratin and positivity for succinic dehydrogenase and alkaline phosphatase stainings, and presented no morphological alterations compared to cultured cells from normal tubular epithelium. Moreover, no difference was observed for fibro-nectin, collagen IV and laminin stains. Analysis by two-dimensional electrophoresis of cellular extracts revealed several changes in protein composition of NEF, the main one being the decrease in NEF cells of a polypeptide with a molecular weight of 120 kD and a pi of 4.8; this polypeptide was a constant finding in normal kidneys. These observations demonstrated that human tubular epithelial cells can be successfully cultured from very small biopsy fragments, which represents a new approach to the study of molecular disorders involving tubular cells in inherited disease. Cultured cells from NEF maintain the same morphological, immunological and cytochemical characteristics as normal tubular cells, but present a few alterations in polypeptide composition which may have pathogenetic relevance. A more careful analysis of these alterations is needed to define the molecular disorder(s) involving the tubule in NEF.

ISSN:0250-8095    

DOI:10.1159/000168170

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

To appraise the prognosis of adult polycystic kidney disease (APKD), 107 patients (58 male and 49 female) were studied retrospectively. The mean age at the time of diagnosis was 45.9 years (ages ranging from 18 to 83 years). Ninety-eight patients had symptomatic APKD. At diagnosis, 30 of these patients had normal renal function, and 68 presented with chronic renal failure (serum creatinine higher than 1.5 mg/dl). Nine of the 107 patients were asymptomatic. Hypertension was the most common feature in symptomatic APKD, present in 51 % of these patients as initial manifestation, and was observed in 46 % of the patients with normal renal function. Forty of the 107 patients (37%) went into end-stage renal disease (ESRD) at a mean age of 52.7 years. The probability of being alive and not having ESRD, estimated using a time-to-event analysis, was 74% by the age of 50, 51 % by the age of 58 and 37% by the age of 70 years. Thus, the prognosis for patients with APKD is better than some reports suggested some years ago.

ISSN:0250-8095    

DOI:10.1159/000168171

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

To evaluate the importance of tubular proteinuria in diabetic nephropathy, we studied the serial changes of micro-albuminuria, microproteinuria and protein patterns by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) in 38 diabetic patients over 8 months. There was a significant correlation between the amount of micro-albuminuria measured by radio-immunoassay and the amount of microproteinuria quantitated by the Coomassie brilliant blue dye binding method (r = 0.976; p < 0.0001). Micro-albuminuria of 50 mg/day was equivalent to microproteinuria of 190 mg/day. Among the 38 diabetic patients, 26 had micro-albuminuria above 50 mg/day, while 12 had micro-albuminuria below this level. There was a significant correlation between the amount of microproteinuria and haemoglobin Ai, showing that the quantity of microproteinuria was affected by metabolic control. Diabetic patients with micro-albuminuria of above 50 mg/day have a significantly higher diastolic blood pressure than those below this level. Among the diabetic patients with micro-albuminuria of less than 50 mg/day, the amount of micro-albuminuria and microproteinuria remained constant, whereas progressive increases in microalbuminuria and microproteinuria were observed among the 12 diabetic subjects with micro-albuminuria above 50 mg/day. These support the prognostic importance of this quantity of micro-albuminuria. The protein patterns as revealed by SDS-PAGE with Coomassie blue staining show a significant loss of low-molecular-weight proteins in 7 patients, which may therefore suggest tubular damage. The loss of tubular proteins persisted over a period of 8 months in all 7 subjects, and the amount gradually increased over this period. To conclude, our results indicate that diabetic proteinuria is characterized by urinary loss of albumin as well as low-molecular-weight proteins. The latter is associated with tubular damage, which may be one of the manifestations of the renal complications of diabetes mellitus.

ISSN:0250-8095    

DOI:10.1159/000168172

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

The diagnostic significance of anticytoplasmic autoantibodies (ANCA) was studied in 71 renal patients. The ANCA test was positive in 67% of patients with Wegener’s granulomatosis (WG), in 35% of those with a simultaneous renal and respiratory tract disease but not diagnosed as WG and in 22% of patients with a renal disease associated with unspecific collagenosis/vasculitis. Among WG patients ANCA positivity clearly correlated with the presence of active renal disease. Interestingly, both ANCA-positive and -negative patients were encountered in the group with acute renal failure and acute extracapillary glomerulonephritis associated with diffuse pulmonary infiltrates. The diagnostic and clinical significance of the ANCA test in these cases remains for the present obscure. In the majority of the ANCA-positive renal patients with respiratory tract abnormalities, the antibodies showed diffuse cytoplasmic staining and were mostly of the IgG class, of both IgG and IgM classes in some cases and of IgG, IgM and IgA classes in 1 patient. In patients with unspecific vasculitis/collagenosis the level of ANCA was rather low, and the distribution of different isotypes resembled that of patients with respiratory symptoms. A certain isotype of ANCA or staining pattern did not mark out any clinicopathologic subgroup among the patients. Our findings indicate that the clinical picture of ANCA-positive patients varies considerably and the ANCA test may not be as specific a marker of WG as previously suggeste

ISSN:0250-8095    

DOI:10.1159/000168173

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Although the fractional excretion of uric acid (FEUA) is known to reflect extracellular fluid volume changes, the diagnostic significance of decreased FEUA in dehydration has not been previously reported. We studied the possible association between low FEUA and acute prerenal azotemia, and its diagnostic value, compared with other traditional indices, in discriminating prerenal azotemia from renal parenchymal causes of acute renal failure. In 65 chronic renal disease patients, 174 FEUA measurements were obtained from 24-hour urine collections. FEUA levels increased as reciprocal serum creatinine levels decreased. All 8 patients with prerenal azotemia showed significantly decreased FEUA values compared with chronic renal disease patients with a comparable degree of serum creatinine elevation, whereas all 7 patients with acute renal failure had FEua values higher than those of chronic renal disease patients with comparable creatinine levels. FEUA values in prerenal azotemia were distinctly lower than those in acute renal failure (p < 0.001). Patients with prerenal azotemia showed a lower fractional excretion of sodium, a lower fractional excretion of chloride and renal failure index, and a higher urine-to-plasma creatinine ratio than those with acute renal failure (p < 0.05). However, these traditional indices were not useful in discriminating between the two conditions. The urine-to-plasma urea nitrogen ratio and the ratio of plasma urea nitrogen to creatinine showed no statistical difference between prerenal azotemia and acute renal failure. We conclude that, in acute azotemia, a decreased FEUA value may represent a reliable indicator of prerenal azotemia in the differential diagnosis of acute renal failure.

ISSN:0250-8095    

DOI:10.1159/000168174

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Previous studies in our laboratory showed that the T cell is a target for parathyroid hormone (PTH) action. It is theoretically possible, therefore, that chronic exposure of the T cells to high blood levels of PTH in patients with chronic renal failure may adversely affect T cell function. We examined in both normal subjects and dialysis patients several aspects of T cell function, including (1) T cell proliferation in response to phytohemagglu-tinin (PHA) mitogen with and without PTH and with and without exogenous interleukin 2 (IL-2); (2) the IL-2 production induced by PHA with and without PTH, and (3) resting levels of cytosolic calcium – [Ca2+]i – and the increment in [Ca2+]; in response to anti-CD3 antibody. Although PHA significantly (p < 0.01) stimulated proliferation of T cells from both normal subjects and dialysis patients, the magnitude of the stimulation was significantly (p < 0.01) smaller in the latter group. In both normal subjects and dialysis patients, exogenous IL-2 alone stimulated T cell proliferation, and the magnitude of the stimulation was similar to that produced by PHA. Also, IL-2 augmented PHA-induced proliferation of T cells from normal subjects, but failed to do so in T cells from dialysis patients. PHA did not augment IL-2 production by T cells from dialysis patients, and PTH did not correct this defect. The resting levels of [Ca2+]i in T cells from dialysis patients were significantly (p < 0.01) higher, and the increments in [Ca2+]i in response to anti-CD3 antibody were significantly (p < 0.01) lower than in T cells from normal subjects. The data demonstrate that the T cell function is impaired in dialysis patients. It is proposed that chronic exposure to high blood levels of PTH in the dialysis patients is associated with a rise in resting levels of [Ca2+]i and with a reduced calcium signal in response to anti-CD3 antibody, and these cellular derangements may interfere with the proper response of T cells to mitog

ISSN:0250-8095    

DOI:10.1159/000168175

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

This manuscript discusses the important question whether rat glomerular macrophages play a significant, early pathologic role in experimental glomerulonephritis. We use a previously described model of accelerated nephrotoxic serum nephritis (NTSN) induced by an intravenous injection of nephrotoxic serum. Glomerular macrophages were isolated from rat kidneys with NTSN and explanted in tissue cultures. Interleukin-1 (IL-1) bioactivity was significantly higher in culture supematants generated by glomerular macrophages isolated from NTSN animals than in control animals. To block the effect of prostaglandins on the IL-1 assay, we cultured the macrophages with indomethacin and assayed IL-1 activity in the culture supematants. The use of indomethacin resulted in a further increase in IL-1 production. The administration of a rabbit antirat macrophage serum prevented the production of IL-1 and reduced the proteinuria in the NTSN rats. Our results indicate that IL-1 protein is increased in the kidneys of NTSN rats and generated by glomerular macrophages. From these observations, we suggest an active role of glomerular macrophages in the pathogenesis of nephritis in this model.

ISSN:0250-8095    

DOI:10.1159/000168176

出版商:S. Karger AG    

年代:1990

数据来源: Karger