ISSN:1660-8151    

DOI:10.1159/000187758

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:1660-8151    

DOI:10.1159/000187759

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

We studied the renin-angiotensin system (RAS) and atrial natriuretic peptide (ANP) after amino acid loading in order to elucidate whether or not glomerular hyperfiltration is mediated by these hormones. Eight healthy controls without kidney disease (grop 1), 8 renal graft recipients (group 2) and 8 patients after nephrectomy (group 3) werde studied. Furthermore, we investigated the influence of amino acid loading on RAS and ANP and glomerular filtration during acute application of captopril in healthy controls. Clearances in inulin (CIn) and para-aminohippuric acid (CPAH) werde determined during an infusion of 0.9% saline and during amino acid loading. CIn increased in healthy controls from 96.5 ± 3.3 to 111.9 ± 4.4 ml/min (p < 0.01), CPAH rose from 577 ± 28.7 to 618.9 ± 38 ml/min (p = NS). During the combined application of amino acid infusion and 25 mg captopril, CIN increased to 125.0 ± 16.4 ml/min/1.73 m2 (p < 0.01) and there was no significant increase in CPAH which was 595 ± 77 ml/min/1.73 m2. There was no significant change in renal vascular resistance, but filtration fraction increased from 17 ± 1 to 19 ± 1% under amino acid infusion and increased further under the application of captopril to 21 ± 2% (p < 0.05). In renal graft recipients, CIn had a tendency to increase during amino acid infusion from 78.4 ± 5.8 to 84.7 ± 6.5 ml/min (p = NS). In patients after nephrectomy, CIn did not increase (84.5 ± 6 ml/min) but CPAH did from 345.7 ± 26.3 to 409 ± 24.1 ml/min (p < 0.05). In healthy controls, ANP was not increased during amino acid infusion: 80.5 ± 9.3 pg/ml as compared to saline infusion with 62.0 ± 10.6 pg/ml (p = NS). During the administration of amino acid infusion in renal graft recipients, ANP was not increased: 283 ± 62.7 as compared to 334 ± 115.7 pg/ml under saline infusion. A renal functional reserve could be shown in healthy persons, but this was grossly diminished in graft recipients and patients after unilateral nephrectomy. Renal functional reserve was maintained in healthy controls during the application of captopril. This investigation indicates that the increase in glomerular filtration rate seen in healthy persons is not media

ISSN:1660-8151    

DOI:10.1159/000187760

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Gastrointestinal infection with verotoxin-producing Escherichia coli (VTEC) has been strongly implicated in the etiology of the hemolytic uremic syndrome (HUS), the leading cause of pediatric acute renal failure. The binding of fluorescein-conjugated VT1 overlaid on to frozen human renal sections has been examined. Sections from biopsies of infants aged < 2 years were compared with those from adult autopsies. VT primarily stained distal convoluted tubules, particularly those adjacent to glomeruli, and collecting ducts. VT-binding was detected within the infant glomerulus but not the adult. Binding of the toxin was removed when the section was pretreated with α-galactosidase, confirming the receptor-binding specificity for globotriaosyl ceramide (galα1-4galβ1-4 glucosyl-ceramide), the glycolipid receptor for VT. These studies may suggest that differential localization of this glycolipid in the pediatric renal glomerulus is a risk factor for the development of HUS following infection with VT

ISSN:1660-8151    

DOI:10.1159/000187761

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Localization of adhesive glycoproteins as the extracellular matrix and their cell surface receptors (integrins) were studied in an attempt to clarify their roles in the progression and aggravation of IgA nephropathy. The relationship between their localization and factors associated with clinical progression was then investigated in 65 patients with IgA nephropathy. The indirect immunoperoxidase method was used to study the distribution of fibronectin (FN), vitronectin (VN), fibronectin receptor (FNR) and vitronectin receptor (VNR). In all cases, FN was present in the glomeruli, mainly confined to the mesangial region, and in some cases, it was observed along the glomerular capillary loops. An expanded mesangial region accompanied higher FN distribution. FNR was present in the mesangial region and glomerular capillary loops, and was higher in the expanded mesangial region. VN was positive in 51 of 65 cases. In all cases, VNR was present in the mesangium and glomerular capillary loops, and its distribution was more predominant in and along the capillary loops than in the mesangial region. The expanded mesangium accompanied higher VNR distribution. There was a significant correlation in distribution between all factors with the exception of VN and FNR. FN, FNR and VNR increased significantly as a degree of histological damage. However, VN was not significantly associated with the degree of histological damage in positive and negative groups. The distribution of FN, FNR and VNR was associated with clinical aggravation factors although the distribution of VN was not. In conclusion, the distribution and functional alteration of FN and integrins in the glomeruli appear to be involved in the progression and exacerbation of IgA nephropathy. However, VN has not yet been clarified.

ISSN:1660-8151    

DOI:10.1159/000187762

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The finding that eluted mesangial IgA and serum IgA from patients with IgA nephropathy had a restricted anionic charge contrasting with normal serum IgA prompted us to study the charge of the kappa and lambda subclasses of IgA. Serum IgA from 11 patients with IgA nephropathy and 11 controls was purified by affinity chromatography by binding to jacalin. The charges of IgA were studied by a novel method. The spectrotype of total IgA was first studied by isoelectric focusing and immunoblotting. IgAλ and IgAκ was further analyzed by reacting with specific monoclonal antibodies. The amount of IgA with different pis was analyzed by computerized densitometry. The anionic :cationic (A: C) ratio of IgA using pi 5.6 as the dividing point was greater in patients (at clinical quiescence and during exacerbation) than in controls (1.67 ± 0.31 versus 1.36 ± 0.27, p < 0.025). IgAλ in both groups was anionic (A:C ratio 2.22 ± 0.77 versus 2.36 ± 0.36) and IgAκ was cationic (A:C ratio 1.15 ± 0.36 versus 1.04 ± 0.39) but no difference in the A:C ratio was demonstrated. The increased A:C ratio in total IgA in patients was due to raised serum IgAλ (κ/λ ratio 1.11 ± 0.14 in patients and 1.51 ± 0.16 in controls, p < 0.01). We had previously shown a predominant mesangial deposition of IgAλ in IgA nephropathy. Animal experiments have revealed the preferential mesangial deposition of immune complexes is related to their anionic charges. Our data of raised anionic IgAλ in IgA nephropathy may be important in determining its selective mesangial binding that could contribute to the im

ISSN:1660-8151    

DOI:10.1159/000187763

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The study was devised to establish the role of prostaglandin E2, prostaglandin1α and thromboxane A2 in the genesis of glomerular hyperfiltration response to a meat meal in healthy humans. To this end, a group of 8 healthy women was studied 4 times: in the control state (study 1), after a meat meal (study 2), following a meat meal associated with intravenous aspirin (study 3) and finally after a meat meal associated with intravenous aspirin following 2-day pretreatment with oral aspirin (study 4). Urinary excretion of prostaglandins and thromboxane increased during the glomerular hyperfiltration response to a meat meal and was suppressed by aspirin administration which did not suppress the renal hemodynamic response to the meat meal. The data do not support a causal role for prostaglandins and thromboxane A2 in the hemodynamic response to acute protein loading

ISSN:1660-8151    

DOI:10.1159/000187764

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

A high incidence of osteopenia is likely in renal transplant recipients in whom pre-existing uraemic osteodystrophy, persisting hyperparathyroidism and glucocorticoids constitute a formidable array of risk factors. The correction of some biochemical and hormonal abnormalities, an increase in body weight and an increase in physical activity following transplantation could favour improvements in skeletal integrity. Using dual energy X-ray absorptiometry (DEXA), we studied prospectively the regional bone mineral density (BMD) of 34 consecutive cadaveric renal allograft recipients who were already established on dialysis. BMD of these patients was measured at the time of transplantation and was repeated at 3, 6 and 12 months following the transplantation. Immunosuppression was achieved using triple therapy: azathioprine, cyclosporin-A and prednisolone. At baseline, total BMD and BMD at the lumbar spine and femoral neck did not differ from age- and sex-matched controls. Females experienced marked and progressive bone loss at the lumbar spine, with less marked changes at the femoral neck. Males, in contrast, experienced substantial reduction of BMD at the femoral neck at 6 months and a recovery at 12 months without significant change at the lumbar spine. Whole body bone mineral content fell transiently in males, with partial recovery by 6 months. No significant correlation was found with the cumulative doses of either corticosteroids or cyclosporin-A, the duration of hospitalisation, the function of the transplant, patient age or menopausal status. In females the loss of BMD at the lumbar spine at 6 months was closely associated with a high parathyroid hormone level (PTH) at transplantation, and in males, the loss of BMD at the femoral neck was associated with a low PTH level at transplantation. We conclude that rapid falls in BMD appear to be inherent to the process of renal transplantation and that strategies to prevent this loss should be evaluated.

ISSN:1660-8151    

DOI:10.1159/000187765

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Circulating immune complexes (CIC) have been described in the hemolytic uremic syndrome (HUS) in children. They may represent an epiphenomenon or could be related to the platelet activation and endothelial damage observed in this disease. In an attempt to define this relationship, we investigated the CIC isolated in 17 patients with the classic form of HUS, by means of monoclonal antibodies against platelet surface glycoprotein lb and IIb–IIIa complex. The negative results obtained do not support the possibility of platelet antigens being constituents of CIC and make an antibody-induced platelet activation in HUS very unlikel

ISSN:1660-8151    

DOI:10.1159/000187766

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Computed tomography (CT) and ultrasonography (US) were performed in 40 patients who had consumed excessive quantities of analgesics ( > l kg) to compare their value in the diagnosis of analgesic nephropathy (AN). The computed tomography and sonographic features were renal papillary calcifications. Renal papillary necrosis (RPN) was documented in 20 of 40 patients by US and in 14 of 40 patients by CT. In 11 patients, both US and CT were positive. In 9 patients, US was positive whilst CT was negative. In 3 patients, CT was positive whilst US was negative. Prevalence of RPN was 50% using US and 35% using CT. Using US as a gold standard, sensitivity of CT was 55%, specificity 85%, positive predictive value 78.6% and negative predictive value 34.6%. Percent agreement with CT and US was 70%. Cohen’s kappa statistic adjusting for chance agreement was 40%. Based on these results, it is found that US yielded a higher percentage of positive cases of RP

ISSN:1660-8151    

DOI:10.1159/000187767

出版商:S. Karger AG    

年代:1994

数据来源: Karger