PubMed Health⌕ Search

Biomedical subjects

A M Davison

Publications and source records attributed to A M Davison.

At least 145 records · Page 8Linked to original sources
PubMed1983

Prorenin and beta-blockade in hypertension.

The role of prorenin in relation to beta-blockade has received little attention. We have studied both active renin and prorenin before and during treatment of hypertension with either nadolol or metoprolol in 44 patients. The ratio of active renin to prorenin before treatment was the best predictor of response; the fall in active renin with treatment did not correlate with the fall in blood pressure, whereas prorenin showed an inverse correlation. We suggest that plasma prorenin is an important indicator of the renin status in hypertensive patients.

Adrenergic beta-Antagonists↗
PubMed1983

Vitamin status in patients on maintenance haemodialysis.

The vitamin status (vitamins A, E, C, Carotene, B1, B2 and B6) of 18 patients receiving maintenance haemodialysis was assessed. All patients were receiving vitamin B1, B2 and B6 supplements and the effect of stopping these supplements on subsequent vitamin status was further studied. Apart from vitamin A, which was significantly increased in all patients, the mean level of all other vitamins was similar to the control group. Despite these normal group means, individual patients could be identified with low or marginally low vitamin C and B2 levels. When the vitamin B complex supplements were stopped, vitamin B2 and B6 remained normal over the subsequent six months maintenance haemodialysis but there was deterioration in vitamin B2 status. Leucocyte vitamin C levels responded well to oral supplements of 400 mg vitamin C per day. This study suggests that vitamin C and B2 supplements are necessary in patients receiving maintenance haemodialysis, other vitamin supplements being unnecessary.

Avitaminosis↗
PubMed1982

Water supply aluminium concentration, dialysis dementia, and effect of reverse-osmosis water treatment.

Dialysis dementia appeared in 18 of 258 patients treated by haemodialysis. All Cases developed in patients treated by home dialysis (150) and none in patients treated exclusively by hospital dialysis (108). Analyses of the domestic water supply for each month on dialysis showed that dementia occurred only in those whose water supply had a high aluminium concentration (greater than 80 micrograms/l). The significant exponential relation (p less than 0.01) between the mean aluminium concentration in the water used to prepare the dialysate and the time taken to death from dementia indicates that there is probably no safe aluminium concentration and that removal of aluminium from water is essential before haemodialysis, particularly in areas where alum is used in water treatment as a clarifying agent. Reverse osmosis treatment satisfactorily removes aluminium and many other substances from water. Its application had a beneficial effect on 7 of 9 patients previously exposed to dialysate prepared from water with a high aluminium content and prevented the appearance of dementia in 24 patients whose water was so treated from the start of haemodialysis.

Aluminum↗
PubMed1982

Haemofiltration for profound dialysis-induced hypotension: removal of sodium and water without blood-pressure change.

Two patients with profound dialysis-induced hypotension were seen, in both of whom sequential ultrafiltration and haemodialysis failed to alleviate their symptoms; in one bicarbonate dialysis similarly produced no improvement. The hypotension was frequently severe enough to necessitate premature termination of the dialysis. Haemofiltration was associated with almost total resolution of symptoms, adequate biochemical control of uraemia, and satisfactory removal of weight gain between dialysis sessions. Profound hypotension during dialysis may become more common as older patients enter dialysis programmes; haemofiltration is a valuable technique in such cases.

Blood↗
PubMed1982

1-Alpha-hydroxy vitamin D in dialysis bone disease: radiological changes after 6 and 12 months of treatment.

Biochemical, radiological and histological indicators of dialysis bone disease were studied before, 6 months (58 patients) and 12 months (48 patients) after starting treatment with 1 alpha-OH D3. Radiographic healing of subperiosteal erosions was seen after 6 months in 60% and after 12 months in 77% of affected patients. Radiographic improvement, however, was not significantly related to reductions in resorptive surfaces seen on quantitative bone histology, nor to changes in plasma concentrations of immunoreactive parathyroid hormone. Metastatic calcification appeared or increased in 43% of patients after 6 months and 52% after 12 months. Periosteal new bone developed or increased in 14% of patients after 6 months and 17% after 12 months. Both metastatic calcification and periosteal new bone formation were associated with high plasma phosphate concentrations, but not with plasma calcium, alkaline phosphatase or parathyroid hormone concentrations. Treatment with 1 alpha-OH D3 produces radiological improvement in the majority of patients with dialysis bone disease, but the lack of correlation with histological changes confirms the need for regular radiographic examination. Metastatic calcification and periosteal new bone formation probably represent toxicity of 1 alpha-OH D3 but may be minimised by phosphate restriction.

Adolescent↗
PubMed1982

Dialysate aluminium concentration and renal bone disease.

We studied 40 patients maintained on regular hemodialysis, using radiology and quantitative bone histology to assess the relationship between renal bone disease and exposure to aluminium. Fractures were significantly more common in patients exposed to high dialysate aluminium concentrations. The histologic indices of osteomalacia were significantly related to the prevailing dialysate aluminium concentration, in such a way that higher aluminium levels were associated with more osteomalacia. Patients who had been exposed to higher concentrations of aluminium also tended to have a lower plasma phosphate concentration, and associated hypercalemia was seen in 6 patients with osteomalacia. These findings suggest that aluminium is a toxic agent associated with a mineralizing defect in the bone of renal failure patients. This may explain the incomplete response of some patients with renal osteomalacia to administration of 1,25-dihydroxy vitamin D.

Adolescent↗
PubMed1982

Changes in human natural killer activity early and late ater renal transplantation using conventional immunosuppression.

The natural killer (NK) cell activity of human peripheral blood lymphocytes falls following major surgical procedures including renal transplantation but in non-immunosuppressed individuals returns to normal levels within the first 72 hr after operation. In renal allograft recipients, if this early postoperative fall is excluded from the analysis, NK cell function appears to follow changes in allograft function, suggesting that in vivo, as has been reported in vitro, NK activity is generated during activation of the alloreactive process. In an additional group of patients whose grafts were functioning for between 3 and 102 months after cadaveric renal transplantation using conventional immunosuppression, NK function was depressed in comparison with that of control subjects. However, some patients who were more than 48 months post-transplant had normal NK cell activity. Collectively, these results suggest that NK cell function may recover despite the continued administration of conventional immunosuppressive agents.

Adolescent↗
PubMed1980

Factors influencing the intestinal absorption of calcium and phosphorus following renal transplantation.

After successful renal transplantation there is continuing malabsorption of calcium and phosphorus. This is due in part to impaired glomerular filtration rate, and in part to the action of steroid on calcium and phosphorus absorption. The effect of steroids is most marked over the first 18 months after transplantation and causes significant malabsorption of calcium and phosphorus even though good graft function is established. Calcium and phosphorus malabsorption can be improved by exogenous 1,25-dihydroxy vitamin D (oral 1 alpha-OH D3 or 1,25-[OH]2D3).

Adolescent↗
PubMed1980

Suppressor cell activity of peripheral mononuclear cells from patients undergoing chronic haemodialysis.

The enhanced in vitro proliferative response of peripheral mononuclear cells (PMNC) when pre-cultured for 24 hours prior to the addition of Concanavalin-A has been used as an indirect parameter of suppressor cell activity in healthy subjects and in patients undergoing chronic haemodialysis. The proliferative response of PMNC from haemodialysis patients is lower than that of control subjects when Con-A is added at the initiation of culture but approximates to that of normal subjects when the addition of Con-A was deferred for 24 hours. The Suppressor Indices of PMNC from haemodialysis patients were at least as great and sometimes greater than those of control subjects but the absolute T-cell counts were lower in haemodialysis patients than in controls. These results suggest that the relative energy of haemodialysis patients is partly attributable to T-cell depletion but this is accompanied by retention, and in some cases augmentation, of suppressor cell activity.

Adult↗
PubMed1979

Resumption of treatment with penicillamine after proteinuria.

Penicillamine has been successfully reintroduced and continued for a minimum of 13 months in 5 patients who developed proteinuria during the first course of the drug. The daily maintenance dose during the second course was 150--250 mg taken midway between 2 meals. Proteinuria did not recur; no significant excretion of fibrin degradation products occurred; complement, urea, creatinine, and serum albumin remained within normal limits. Urine microscopy showed no abnormality.

Arthritis, Rheumatoid↗
PubMed1979

Ruptured hepatic aneurysm in systemic lupus erythematosus.

We report on a patient with systemic lupus erythematosus (SLE) who suffered catastrophic haemorrhage following rupture of an intrahepatic aneurysm. The association between hepatic artery aneurysm and SLE has not been recorded previously, but we have found evidence from the literature that there may be an association between autoagressive disorders and this surgical emergency.

Adult↗