Search PubMed⌕ Search

Biomedical subjects

W J Johnson

Publications and source records attributed to W J Johnson.

At least 127 records · Page 7Linked to original sources

Calcium flux during hemodialysis.

A system of equations has been derived, and examined, to decribed membrane permeability and calcium fluxes within a commonly used hemodialyzer, the Mini-Kiil. By a statistical technique of sequential multiple regression analysis, factors which might influence these variables were tested on data derived from 74 hemodialysis periods in 5 patients. Calcium flux from plasma to dialysate was influenced positively by dialysate calcium concentration and plasma volume flow and negatively by dialysate volume flow. Calcium flux from dialysate to plasma was influenced positively by dialysate calcium concentration and plasma volume flow and negatively by plasma phosphate concentration. Net calcium flux from dialysate to plasma was influenced positively by the calcium gradient (dialysate calcium minus plasma ultrafiltrable calcium) and plasma volume flow and negatively by plasma phosphate concentration (coefficient of multiple correlation =0.970). Because of the magnitude of regression coefficients, manipulations of the dialysate calcium concentration and plasma phosphate concentration were concluded to be the most practical means of adjusting calcium delivery during dialysis.

Calcium↗

Effectiveness of intestinal phosphate binders in patients maintained by hemodialysis.

Two formulations of aluminum phosphate binders-aluminum hydroxide suspension and aluminum carbonate powder in the form of capsules-were found to be equally effective in lowering the plasma phosphate concentration. The effective dose was 4 g/day given in divided doses before meals and at bedtime. Side effects were negligible with this dosage for both preparations, but aluminum carbonate capsules were preferred by most patients because of the greater convenience of the capsule form. Coincident with the lowering of serum phosphorus concentrations, serum parathyroid hormone concentrations decreased approximately 30% from levels obtained while patients were taking placebo.

Administration, Oral↗

Ultrafiltration followed by haemodialysis. A longterm trial and acute studies.

Separate ultrafiltration followed by haemodialysis (U.F.-H.D.) using Gambro Major or Cordis-Dow hollow-fiber dialyzers were evaluated in 10 dialysis patients over a mean period of 4 1/2 months and 455 U.F.-H.D. procedures. Fluid control was facilitated in oedematous patients but the number of hypotensive episodes during the combined procedure requiring intravenous 5% saline did not significantly decrease. No significant improvement in hypertension was noted. Ultrafiltration (U.F.) alone for acutely water overloaded, azotaemic patients proved very useful. Two to five liters of oedema fluid could be removed asymptomatically in one to three hours using transmembrane pressures of 250 to 500 mmHg and U.F. rates of 10 to 42 ml/min. Two patients became acutely and symptomatically hypotensive. One was an insulin dependent diabetic in whom 3800 ml were removed in 75 minutes and the other a hypertensive patient undergoing treatment with Minoxidil and propranolol.

Diabetes Mellitus, Type 1↗

Renal transplantation in patients with insulin-dependent diabetes mellitus.

Forty patients (including 37 juvenile diabetic patients) with insulin-dependent diabetes mellitus and end-stage renal failure received 42 renal allografts during the interval from June 1970 to December 1975. Of the 30 patients who are alive (between six and 72 months after transplantation; average, 29 months), 19 have been fully rehabilitated. Gangrene of peripheral extremities occurred in 30% of the survivors. The use of "pretreated" cadaveric kidneys in the diabetic patient may become an attractive alternative to grafts from living related donors. Renal transplantation with living related and pretreated cadaveric donor kidneys is the treatment of choice and is superior to dialysis in the insulin-dependent diabetic patient with end-stage renal disease.

Adult↗

Lipids from subcellular fractions of the tegument of Hymenolepis diminuta.

Lipids comprised 37% and 22.1%, respectively, of the day weights of brush border- and vesicle-rich fractions separated by differential centrifugation of isolated H. diminuta tegument. Neutral lipids of both fractions were rich in cholesterol, but also contained small amounts of glycerides, sterol esters, and (in brush borders) free fatty acids. Phosphatidyl ethanolamine was the most prevalent polar lipid in both fractions, and was particularly abundant (63.4% of total polar lipids) in vesicles; sphingomyelin, not previously reported from H. diminuta, was also present. Polar lipids of both tegumental fractions resembled each other but differed from whole worm polar lipids in fatty acid composition. Tegumental polar lipids contained lower levels of long-chain, polyunsaturated fatty acids than reported for corresponding lipids of whole worms.

Cestoda↗

Optimum dialysate calcium concentration during maintenance hemodialysis.

A dialysate calcium concentration of 7 mg/100 ml is optimal for hemodialysis. Provided plasma phosphate concentrations are maintained within the normal range and provided that thrice weekly dialysis is employed, this concentration of calcium in the dialysate restores plasma-ionized calcium level to normal, provides sufficient calcium during dialysis to offset loss of calcium in the stool, and prevents loss of calcium from bone. Several clinical trials indicate that it reduces the risk of progressive secondary hyperparathyroidism. Normalization of plasma calcium and phosphate levels reduces (but does not eliminate) the risk of metastatic calcification.

Bone and Bones↗

Hyperosmolar nonketotic syndrome and steroid diabetes. Occurrence after renal transplantation.

So-called steroid (glucocorticoids) diabetes developed in 11 (5.5%) of 202 patients receiving 216 renal allografts between December 1963 and June 1974. In three of the 11 patients, hyperosmolar nonketotic syndrome was present at diagnosis; all of the three recovered. Eight of the 11 patients survived with functioning allografts, and only one of the eight requires insulin. Hyperglycemia has been detected in most transplant patients tested in the immediate postoperative period. Factors (including stress from surgery and treatment with drugs such as furosemide) predispose to this condition.

Adolescent↗

Isiopathic postpartum renal failure: review and case report of a successful renal transplantation.

Idiopathic postpartum renal failure is a syndrome of acute, rapidly progressive oliguria, azotemia, and microangiopathic hemolytic anemia occurring shortly after a normal pregnancy and usually terminating fatally. Of 25 patients described in the literature, 8 survived: 1 recovered almost normal renal function, 4 had renal functional impairment, and 3 required maintenance hemodialysis. This report concerns a patient who survived after nephrectomy, hemodialysis, and successful renal transplantation from a living related donor. Theoretic and experimental studies indicate that heparin, platelet inhibitors, and fibrinolytic agents should be beneficial if given early. If the disease progresses to the irreversible stage, nephrectomy and renal transplantation are warranted since the disorder does not seem to recur after transplantation.

Acute Kidney Injury↗

Uremic neuropathy. III. Controlled study of restricted protein and fluid diet and infrequent hemodialysis versus conventional hemodialysis treatment.

The effect of a treatment schedule of restricted protein and fluid intake and of infrequent hemodialysis (schedule 1) as compared to a conventional hemodialysis treatment schedule (schedule 2) on the presence and severity of peripheral neuropathy has been studied in a small group of patients using a crossover design. Using the neurologic evaluation and quantitative assessment of cutaneous sensation and of nerve conduction as indices of peripheral nerve function, we have not demonstrated any worsening of peripheral nerve function from markedly curtailing the frequency of hemodialysis and modifying the diet. Because of the small size of the study, the preponderance of patients receiving the test treatment schedule first, and the possibility that nerve function slowly worsens with time, it is not possible to say with certainty that the test or the control treatment schedule might adversely affect peripheral nerve function. If such an effect is present it would appear to be small.

Adult↗