Search PubMed⌕ Search

Biomedical subjects

J S Cameron

Publications and source records attributed to J S Cameron.

At least 271 records · Page 15Linked to original sources
PubMed1982

Corynebacterium hofmannii infection after renal transplantation.

A case of malakoplakia affecting the entire urinary tract is described. The patient had received a cadaveric renal transplant and had required particularly heavy immunosuppression because of recurrent rejection episodes. Heavy hematuria developed, and this was followed by obstruction at the vesico-ureteric junction. Despite adequate drainage via a nephrostomy, the graft ceased functioning, and was explanted. Although appropriate antibiotics were given, the patient died. The organism responsible for triggering the malakoplakia was Corynebacterium hofmannii, and this is only the third report of this organism as a human pathogen. However, other coryneform bacteria have been reported as being pathogenic in immunosuppressed subjects, and should be sought when more common organisms cannot be cultured in such patients showing signs of infection.

Adult↗
PubMed1982

Significance of mesangial IgM deposition in "minimal change" nephrotic syndrome.

During a 6-year period, 64 patients with a nephrotic syndrome, shown histologically to result from minimal change nephropathy, were studied for a mean of 4.5 years. Fifty of the patients showed no glomerular immunoglobulin on immunofluorescent or immunoperoxidase study, but 14 had mesangial deposits of IgM. The onset characteristics, response to treatment, and long-term course were similar in the two groups. We conclude that IgM deposition in the mesangium in patients with minimal change nephrotic syndrome is of no prognostic value, and our data do not suggest that this group of patients, although a histopathologic entity, represent a clinically distinct group.

Adolescent↗
PubMed1982

Effects of epinephrine on automaticity and the incidence of arrhythmias in Purkinje fibers surviving myocardial infarction.

The role of the sympathetic nervous system in the development of late-phase ventricular arrhythmias occurring 24 hr after myocardial infarction was investigated using canine ventricular preparations in vitro. One day after two-stage ligation of the left anterior descending coronary artery, transmembrane action potentials from subendocardial Purkinje fibers were monitored in noninfarcted (NZ) and infarcted (IZ) zones during Tyrode's superfusion at 37 degrees C. In combined preparations incorporating both NZ and IZ, epinephrine (10(-7)-10(-5)M) produced dose-dependent increases in spontaneous rates of depolarization, slope of phase 4 depolarization and incidence of spontaneous and induced arrhythmias. In particular, premature electrical stimulation induced increased numbers of unstimulated responses or rapid, repetitive depolarizations. These responses to the drug were antagonized by propranolol (10(-6)M) but not phentolamine (10(-7)M). Epinephrine appeared to promote the functional dissociation of conducted impulses often observed in the IZ of combined preparations. In preparations excised from either NZ or IZ alone, epinephrine induced elevated spontaneous firing rates, particularly in the IZ, but no increase in arrhythmias. These data suggest that elevated levels of beta adrenergic receptor stimulation 24 hr after myocardial infarction may increase ventricular vulnerability to arrhythmias arising through enhanced automaticity or reentry.

Animals↗
PubMed1981

Uric acid crystal-induced nephropathy: evidence for a specific renal lesion in a gouty family.

Gout is principally a disease of middle-aged men. There has been a lot of discussion over the cause of the renal lesion, whether it is age, hypertension or crystal induced, as single factors or in combination. We have recently been able to study renal biopsies from three related young women with an hereditary gout, and another girl with 2,8-dihydroxyadenine crystal nephropathy. All were normotensive. These findings were compared with the findings of a crystal-induced nephropathy in pigs. In the renal biopsies many stages of acute and chronic nephritis were found which were similar to the crystal nephropathy in pigs. We concluded that the cause of the original lesion in the women was crystal deposition in the tubules, that crystals were not necessary to keep a non-specific nephritis active and that age and hypertension need not be contributory factors.

Adenine↗
PubMed1981

Effect of a long-term fat-modified diet on serum lipoprotein levels of cholesterol and triglyceride in patients on home haemodialysis.

1. Changes in serum total and lipoprotein fraction triglyceride and cholesterol levels were studied in 24 adults on home haemodialysis. Half the patients were randomly allocated to a low cholesterol (mean 200 mg/day), fat-modified diet (mean polyunsaturated/saturated fat ratio of 1.0 with a mean of 43% of the total energy content derived from fat). 2. Before dietary manipulation, triglyceride levels in all lipoprotein fractions were significantly higher (P less than 0.02) than in a control group of age and sex matched normal subjects. Total cholesterol, very-low-density-lipoprotein (VLDL) and low-density-lipoprotein (LDL) cholesterol were also significantly raised (P less than 0.02), but high-density-lipoprotein (HDL) cholesterol was normal. In the patients on a fat-modified diet triglyceride levels did not alter in any of the lipoprotein fractions. Total cholesterol and LDL cholesterol levels fell significantly into the normal range (P less than 0.002 and less tha 0.001 respectively) but VLDL and HDL cholesterol levels did not change. 3. Hypertriglyceridaemia is the most common lipid abnormality in patients with renal failure and a long-term fat-modified diet is, therefore, of limited therapeutic importance in these patients unless there is a low HDL/LDL cholesterol ratio.

Adolescent↗
PubMed1981

Recurrence of focal segmental glomerulosclerosis in renal allografts.

Thirty-one renal allografts placed in 25 recipients with renal failure from biopsy-documented focal segmental glomerulosclerosis (FSGS) were reviewed. These represent all of the cases with this renal histology transplanted over 13 years. Recurrence of the lesion was demonstrated histologically in five recipients. A nephrotic syndrome occurred in all five patients and failure of the graft in two. Of 20 recipients who did not show a nephrotic syndrome, allograft histology in 12 did not show FSGS in any. From these data and a review of the literature, the risks of transplantation in patients with FSGS are assessed. Recipients under the age of 15 and with a course into renal failure of less than 3 years show recurrence in about 50% of cases. Of this 50%, about one-half will lose their grafts from the recurrence within 5 years, but some may show good function for many years, despite proteinuria or a nephrotic syndrome.

Adolescent↗
PubMed1981

Systemic lupus erythematosus with nephritis.

Thirty-six patients with the onset of symptoms of systemic lupus erythematosus before age 20 years (23 aged less than 15 years at onset) were studied during a 15-year period. All had clinical evidence of nephritis. They were followed for a mean of 5 years (range 6 months to 13 years) or until death. Survival was calculated to be 77% at 10 years for those aged less than 15, and 74% for those aged less than 20, from the onset of clinical nephritis. At referral, renal function was already impaired in two-thirds of patients. Renal biopsies showed mild focal or proliferative changes in 19% of patients, membranous lesions in 11%, and diffuse proliferative lesions in 70%. Three (8%) patients died during follow-up, all from sepsis, and 3 (8%) others required chronic haemodialysis for terminal renal failure. The prognosis even of severe lupus nephritis in childhood and adolescence has improved in recent years. Side effects of treatment remain an important cause of death and morbidity.

Adolescent↗
PubMed1981

High dose frusemide in acute renal failure: a controlled trial.

Fifty-eight patients in established acute renal failure following trauma or surgery were allocated in a prospective and random fashion to two different diuretic regimes. In the control group, 1 g frusemide was given as a single injection over four hours. In the test group, frusemide was then continued either intravenously or orally in a dose of 3 g/24 hr until a urine output of 200 ml/hr was sustained or until the plasma creatinine fell below 300 mumoles/l. Oliguria was reversed or prevented in 24 of 28 patients given sustained frusemide, but in only 2 patients given a single injection. However, the number of dialyses and duration of renal failure and mortality were not different in the two groups. The serious complication of deafness occurred in two patients and in one of them this was permanent.

Acute Kidney Injury↗
PubMed1981

Presentation and course of primary amyloidosis of the kidney.

The case histories of nineteen patients who were seen in one renal unit between 1966 and 1978 and who were found to have primary amyloidosis are reviewed. Most were aged more than fifty and presented with the nephrotic syndrome without particular diagnostic features although electrophoresis of plasma and urine revealed abnormal immunoglobulins in a minority. Treatment was generally only symptomatic and most patients died within six months of diagnosis usually from renal failure. At the time of writing only the two patients treated by maintenance haemodialysis are still alive.

Aged↗
PubMed1981

Platelet-aggregating immune complexes and intraplatelet serotonin in idiopathic glomerulonephritis and systemic lupus.

Immune complex-like material was studied using the platelet-aggregation test (PAT) in 114 patients with idiopathic glomerulonephritis and 55 patients with SLE nephritis, and the results obtained compared with Raji cell and Clq-binding assays. The platelet-aggregating material was not thrombin, and eluted from Sepharose CL/6B columns with a molecular weight of greater than 500,000 daltons. Sera from 17 of 55 patients with SLE nephritis were positive in all three assays, 50/55 in at least one assay. No circulating material was detected by the Raji cell assay in idiopathic glomerulonephritis patients, but both the Clq-binding and PAT assays detected material in patients with acute post-infectious nephritis and mesangiocapillary glomerulonephritis. Patients with membranous nephropathy and Henoch-Schönlein purpura were positive in the PAT, although generally negative in the other assays of immune complexes. The amount of platelet-aggregating material (PAM) found in the sera of patients with both idiopathic glomerulonephritis and SLE nephritis correlated closely with the depletion of intraplatelet serotonin, suggesting that this material is a major mechanism of in vivo platelet activation in these patients.

Antigen-Antibody Complex↗
PubMed1981

The long-term outcome of idiopathic membranous nephropathy.

Thirty-five consecutive patients with renal biopsy appearances of idiopathic membranous nephropathy, who were initially studied between 1960 and 1969, were reevaluated in 1979 to determine (a) the long-term outcome of idiopathic membranous nephropathy, and (b) whether any clinical or biopsy features at onset would permit prediction of long-term outcome. After fifteen years, actuarial analysis showed that approximately half the patients would be in remission; the rest dead or on dialysis/transplantation programs. Entry into renal failure, in those who ran this course, started at three years after diagnosis and continued steadily for at least another ten years. Likewise, remission was seen as early as one year from onset, but patients were still going into remission after thirteen years of proteinuria. No feature in the glomeruli predicted outcome, but interstitial and vascular changes were seen more frequently in those whose disease persisted or worsened. No onset feature predicted a poor outcome reliably, but younger patients did better than older, and all three children with initial macroscopic hematuria went into remission.

Adolescent↗