PubMed Health⌕ Search

Biomedical subjects

J E Scoble

Publications and source records attributed to J E Scoble.

At least 55 records · Page 3Linked to original sources
PubMed1993

Effect of cyclosporin A on endothelin synthesis by cultured human renal cortical epithelial cells.

We report here for the first time that human renal proximal tubular cells secrete endothelin, clear evidence of de-novo endothelin synthesis by these cells and the effect of cyclosporin A (CsA) on endothelin synthesis both in short-term (24 h) and medium-term (5-day) culture. Human renal cortical epithelial cells were cultured and shown to possess proximal tubular characteristics. These cells produced endothelin in culture in a time-dependent manner, as measured by radioimmunoassay (291.6 +/- 51.4 pg/well/24 h). Furthermore, endothelin production by these cells was significantly decreased by up to 80% by cycloheximide (1051.8 +/- 54.9 pg/mg cell protein/24 h versus 253.2 +/- 12.6 pg/mg cell protein/24 h), showing that these cells actively synthesize endothelin. In short-term culture (24 h), CsA significantly inhibited endothelin synthesis at a medium concentration of 10,000 micrograms/l. No change in endothelin synthesis was seen at lower CsA concentrations. In contrast, over a 5-day period, a non-significant increase in endothelin synthesis was observed at CsA concentrations of 2000 micrograms/l (152.5 +/- 20.4%); however, cell growth was significantly decreased at this concentration (71.33 +/- 6.39%). Using a newly developed two-site immunoradiometric assay specific for endothelin-1 (ET-1), we demonstrate that ET-1 is the major endothelin isoform produced by human renal proximal tubular cells.

Animals↗
PubMed1993

Patients with atherosclerotic renovascular disease presenting to a renal unit: an audit of outcome.

During a 6 year period 60 patients with atherosclerotic renovascular disease were followed by a single renal unit. Angiotensin converting enzyme inhibitors were being taken by 22% of patients at the time of diagnosis of the atherosclerotic renovascular disease. Intervention to revascularize renal tissue by surgery or angioplasty was performed in 32 patients. Revascularization was not undertaken because of unilateral disease, patient preference, poor operative risk or renal size. The mean age for the nonintervention group was 66.9 years and 63.4 years for the intervention group. Peripheral vascular, disease was common in both groups (96% nonintervention group versus 86% intervention group). There was a statistically significant difference in improvement in renal function in the intervention group (34.4% versus 10.7%) in spite of more patients being dialysis dependent in the intervention group (28.1% versus 14.3%). There was no statistically significant difference in survival between the two groups although the trend was for better survival in the group with intervention. Patients presenting with impaired renal function and atherosclerotic renovascular disease can have useful improvement in renal function with revascularization without any detriment to survival.

Aged↗
PubMed1992

Para-aortic nodal irradiation for early stage testicular seminoma.

Early stage seminoma of the testis has an excellent prognosis when post-orchidectomy para-aortic and ipsilateral pelvic radiotherapy is given. However, studies on testicular lymphangiograms and the rarity of isolated pelvic nodal disease suggest that pelvic radiotherapy is not necessary, except in cases where there is the possibility of altered lymphatic drainage. We report on 27 patients with stage I and IIA seminoma treated between 1983 and 1989. Seventeen patients received radiotherapy to the para-aortic region only. There have been no pelvic recurrences. No long term complications have been encountered. We discuss the reported data which suggest that a reduced complication rate should result from the proposed field reduction. We conclude that irradiating only the para-aortic region in early stage seminoma is logical, should not increase the relapse rate and should reduce the complication rate.

Adult↗
PubMed1992

Screening for renovascular disease with captopril-enhanced renography.

Changes in renal function caused by angiotensin-converting-enzyme (ACE) inhibitors can be detected on 99mTc-DTPA renography so that DTPA scanning before and after a single dose of captopril can be used to screen for renovascular disease. We have performed captopril-DTPA scans with renal arteriography on 104 patients, of whom 27 had renal artery stenosis, all due to atheroma. Using a 5% fall in divided function or a delay of greater than 15 min in time to peak activity on one side after captopril, or the finding of greater than 90% divided function on one side before captopril as criteria for a positive scan, a sensitivity of 93% and specificity of 70% was achieved. The negative predictive value of the test in our population was 93%. Bilateral improvement in renographic function after captopril was seen in patients with accelerated phase hypertension. The presence of bilateral renal artery disease did not reduce the sensitivity of the test, but sensitivity was reduced (75%) in patients with renal impairment. Clinical characteristics in our patients most strongly associated with renal artery stenosis were abdominal bruit, recurrent left ventricular failure, and peripheral vascular disease. In view of the well-publicized risks of ACE inhibitor therapy, care should be exercised in the use of these agents in such patients.

Adult↗
PubMed1992

Use of the hepatic arterial circulation for renal revascularisation.

Renal artery stenosis is increasingly being diagnosed as a cause of hypertension and renal impairment. Surgical intervention can restore function and improve hypertension in selected cases. Over a 42 month period, 12 patients with atherosclerotic renovascular disease underwent surgical revascularisation using the hepatic arterial circulation. All had disease of both renal arteries and 11 had some degree of renal impairment, with five requiring dialysis before operation. There were two deaths within 30 days of operation, eight patients had improved renal function after operation and three of the patients previously on dialysis became dialysis free. The hepatorenal method of renal revascularisation is described and its advantages discussed.

Aged↗
PubMed1992

Increased Na(+)-dependent D-glucose transport and altered lipid composition in renal cortical brush-border membrane vesicles from bile duct-ligated rats.

Erythrocyte membranes of patients with liver disease are characteristically enriched in cholesterol, a change known to impair several carrier-mediated membrane transport functions. In the present study we have assessed whether experimental liver disease can affect the membrane lipid composition and transport function of kidney epithelial cells. Small (about 5%) but significant (P less than 0.01) increases were found in the cholesterol-to-phospholipid molar ratio (C/PL) of rat renal cortical brush-border membrane (BBM) vesicles 3, 8, and 15 days after bile duct ligation which correlated closely with increased fluorescence polarization, i.e., decreased membrane fluidity (r = 0.75, P less than 0.001; n = 27). A lipoprotein-mediated pathogenesis was suggested by the close relationship between BBM C/PL and plasma C/PL (r = 0.69, P less than 0.001). The mean high-affinity Na(+)-coupled D-glucose uptake by BBM vesicles was higher 1, 3, 8, and 15 days after ligation than in non-operated rats, significantly so at 3 and 8 days (611 +/- 37 and 593 +/- 22 vs. 507 +/- 21 pmol/mg protein per 4 sec; P less than 0.05), and was positively correlated with BBM C/PL (r = 0.58, P less than 0.01) and fluorescence polarization (r = 0.41, P less than 0.05). Brief incubation of BBM vesicles from normal rats with cholesterol-rich phospholipid liposomes simultaneously increased BBM C/PL and Na(+)-dependent D-glucose uptake. Stimulation of BBM Na(+)-glucose cotransport in ligated rats was not due to delayed dissipation of the Na+ gradient or to a more rapid development of membrane potential. High-affinity Na(+)-dependent D-glucose uptake kinetics in 3-day bile duct-ligated rats showed a lower Kt, without an alteration in maximum velocity, Vmax, compared to sham-operated animals (0.298 +/- 0.015 vs. 0.382 +/- 0.029 mM; P less than 0.05), whilst the binding dissociation constant, Kd of high-affinity phlorizin binding sites was reduced by ligation (0.453 +/- 0.013 vs. 0.560 +/- 0.015 microM; P less than 0.001). We conclude that an early effect of bile duct ligation is to enrich renal cortical brush-border membranes in cholesterol, thereby decreasing membrane fluidity and stimulating Na(+)-dependent D-glucose uptake by increasing the affinity of the carrier.

Animals↗
PubMed1991

Hyperfractionated accelerated radiotherapy for carcinoma of the oesophagus.

We report on 48 patients with carcinoma of the oesophagus treated by hyperfractionated accelerated radiotherapy. The patients, aged 46 to 93 years, were considered suitable for radiotherapy on their performance status irrespective of the presence of metastases. The radiotherapy was given three times a day over 2 weeks with a minimum of 3 h between treatments. The treatment was well tolerated acutely and to date there have been no unacceptable long-term side-effects. Dysphagia was improved in 39 (81.2%) patients. Product-limit survival was 35.7%, 18.5% and 12.3% at 1, 2 and 3 years. We conclude that this regime is feasible within the normal working day, well tolerated, effective and the shorter overall treatment duration desirable.

Adenocarcinoma↗
PubMed1991

The use of captopril-DTPA scanning in the diagnosis of atherosclerotic renal artery stenosis in patients with impaired renal function.

We have analyzed our use of captopril-diethylene-triaminepentaacetic acid (DTPA) scanning in patients presenting to the Royal Free Hospital predominantly with renal impairment. The sensitivity was found to be as good in patients with bilateral disease or disease of a single kidney as in patients with unilateral disease. On a number of occasions, though, the scan suggested unilateral disease when bilateral disease existed. There were, however, a large number of patients for whom captopril-DTPA scanning was not performed because of severe renal impairment or the possibility of renal artery stenosis in a single functioning kidney.

Aged↗
PubMed1990

Conversion of stable renal allografts at one year from cyclosporin A to azathioprine: a randomized controlled study.

Seventy-seven stable, nondiabetic, cadaveric renal transplants were randomized at 1 year to convert from cyclosporin A to azathioprine or to continue on cyclosporin A. Prednisolone was increased twofold during the period of conversion, and there was a 3-week overlap period during which azathioprine and cyclosporin A were given. No grafts were lost due to rejection related to conversion, but 9 of the 33 patients who were randomized to convert experienced rejection episodes and 6 were returned to cyclosporin A. Conversion to azathioprine resulted in a drop in creatinine and improvement in blood pressure control. In the group randomized to stay on cyclosporin A, 6 patients had to be subsequently converted to azathioprine because of cyclosporin A toxicity in spite of well-controlled plasma levels. The creatinine levels after successful conversion remained stable whereas those of the patients continuing on cyclosporin A showed a progressive decline. We conclude that conversion from cyclosporin A to azathioprine can be achieved safely. Progressive deterioration in graft function with continuing cyclosporin A therapy does occur and should be taken as an indication for conversion.

Adult↗
PubMed1990

Cyclosporin-induced renal magnesium leak in renal transplant patients.

Renal transplant patients (n = 116) attending an outpatients clinic were screened for hypomagnesaemia. No azathioprine-treated patients (n = 46) but 24% (17 of 70) of the cyclosporin treated patients were hypomagnesaemic. The hypomagnesaemia in all cases was associated with a renal magnesium leak. This leak did not correlate with plasma bicarbonate, urate, calcium, cyclosporin or creatinine concentrations, nor did it correlate with the use of loop diuretics or duration of the transplant. A renal magnesium leak is common in renal transplant patients treated with cyclosporin and it is independent of other markers of nephrotoxicity.

Adult↗