New TaqI RFLPs at the DXS52 (St14) locus in the black population.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to P Barjon.
Explore the source record for details and available documents.
The 67-kDa calelectrin is the largest member of a family of Ca2+-binding proteins that associate with membranes and phospholipids in a Ca2+-dependent manner. Oligonucleotide probes based on peptide sequences obtained from purified bovine 67-kDa calelectrin were used to screen a human retina cDNA library, and the complete primary structure of human 67-kDa calelectrin was deduced by DNA sequence analysis. The protein consists of eight 68-amino acid repeats separated by linking sequences of variable lengths. It is highly similar to the human lipocortin I and II sequences, each of which contains four such repeats. The amino termini of the three proteins show no sequence similarity; however, in the repeated regions the proteins are 42-45% identical in sequence. Analysis of the 16 repeats from the three proteins provides insights into the structural basis for Ca2+-dependent phospholipid binding. These data place the calelectrins and the lipocortins into the same gene family and suggest that these proteins have similar functions and have evolved from a common ancestor.
17 alpha-hydroxylase deficiency is a rare form of congenital abnormality in steroid synthesis, usually associated with moderate arterial hypertension and suppression of the renin-angiotensin system in a young adult. We report on a 45 years old woman with malignant hypertension (220/135 mmHg, severe retinopathy with papilledema, progressive renal insufficiency with serum creatinine over 300 mumol/l) of recent onset. Biological exploration revealed a metabolic alkalosis, a moderate hypokalemia (3 mmol/l), with elevated urinary excretion of potassium. Plasma aldosterone concentration (33 ng/dl) and plasma renin activity (17 ng/ml/h) were elevated. Acute captopril administration was followed by a marked (-29 p. 100) decrease in mean arterial pressure. In this 46 XX patient, a primary amenorrhea had never been explored; clinical examination disclosed the absence of female secondary sex characteristics. Plasma cortisol was low (203 mmol/l) as were plasma androgens (testosterone 0.55, androstene dione 0.19, delta HEA less than 0.1 nmol/l respectively) and oestrogens (oestradiol 59 nmol/l). Elevated levels of progesterone and pregnenolone sulfate (12.1 and 2027 nmol/l respectively) contrasted with decreased levels of 17 OH progesterone (0.35 nmol/l). Computed tomography revealed a subnormal right adrenal gland and a pseudo-tumoral aspect on the left side. Treatment with dexamethasone and combined antihypertensive drugs (captopril, nifedipine and atenolol) resulted in normalisation of blood pressure and secretion of renin and aldosterone but renal function did not fully recovered. Thus, the hypertension of 17 alpha-hydroxylase deficiency can follow a malignant course in association with a marked activation of the renin-angiotensin system.
A probable diagnosis of an incomplete form of von Hippel Lindau disease was made in a case of combined cerebellar hemangioblastoma, pontobulbar cavitation and bilateral pheochromocytoma. A survey of the literature review found only 3 similar cases among 64 patients reported as having combined lesions. A wide variety of lesions are in fact encountered.
Explore the source record for details and available documents.
A 71-year old man experienced nephrotic syndrome and acute renal failure 13 months after the introduction of fenoprofen calcium, 900 mg/day, as treatment of right hip osteoarthritis. Clinical course and laboratory data were consistent with toxic nephropathy; kidney biopsy showed tubulo-interstitial nephritis with glomerular minimal change lesion. Renal function returned spontaneously to normal, after withdrawal of the drug. The clinical literature on nephrotic syndrome and reversible acute renal failure associated with non-steroidal anti-inflammatory drugs is reviewed.
A 24-year old female patient developed extramembranous glomerulonephritis 8 months after acute hepatitis-B with virus antigen persisting in the serum. Two years later, the glomerular lesions were found to be clinically and histologically cured, with parallel disappearance of the antigen from the serum. Although the presence of HBsAg in the glomeruli could not be demonstrated, it is likely from the sequence of events that hepatitis-B virus was responsible for the renal disease.
A syndrome of chronic hypernatremia (range 148 to 161 mmoles/l) and partial hypopituitarism (growth hormone and gonadotropin deficiencies) is reported in a 27 year-old man with sarcoid hypothalamic involvement. The patient did not complain of thirst and spontaneous fluid intake was not sufficient to restore the serum sodium to normal. However, when larger amounts of water were given (50 ml/kg for 180 min), the plasma osmolality returned to normal values in 3 hours. Blood volume values were found subnormal on two occasions on free diet (63 and 74% of the theorical normal values) and plasma renin activity was elevated (22 ng/ml/hour). Plasma vasopressin (AVP) concentrations (range < 1 to 1.9 pg/ml) were inappropriately low for the degree of plasma osmolality and remained markedly subnormal when hypertonic saline was infused (NaCl 5%, 10 ml/min for 60 min). However, the secretory stores and hemodynamic control of AVP release were intact since a rise in plasma AVP to 10.8 pg/ml was observed after induction of arterial hypotension with sodium nitroprusside infusion. These results provide further direct evidence fo the dysfunction of the thirst mechanism and the osmotic contol of AVP release. They support the concept that osmoreceptor areas are anatomically distinct from the neurohypophyseal AVP secretory system and that neural inputs from baroreceptor and osmoreceptor cells are completely separated.
The response of arterial pressure to an infusion of saralasin was compared to the effect of surgical correction of renal vascular lesions (3 to 6 months after surgery) in eleven patients whose hypertension was associated with uni or bilateral stenosis of renal artery. Saralasin was infused after four days of dietary sodium restriction (10-40 mEq/day). An excellent correlation (r = 0.83, p less than 0.005) between the effects of saralasin and surgery was obtained. There was no correlation between the response to saralasin or to surgery and the ratio of renal vein renin activities. It is suggested that saralasin may be a good tool for predicting the effect of surgery in renovascular hypertension, when infused in moderately sodium depleted patients.
The effects on arterial pressure of saralasin and short-term (seven days) administration of the cardioselective beta-blocker atenolol were compared in 21 patients with various forms of hypertension. During saralasin administration mean arterial pressure (MAP) decreased by 8.8 +/- 2.1 per cent. Atenolol administration was associated with a MAP fall of 23.6 +/- 2.9 per cent. The change in MAP induced by atenolol was higher than that produced by saralasin (P less than 0.001) and no significant correlation (r = 0.40, P greater than 0.05) between their respective effects was found. These results suggest that the antihypertensive action of atenolol is not related to pre-treatment activity of the renin-angiotensin system as estimated by the hypotensive effect of saralasin. Other mechanisms should be sought in order to explain the effectiveness of this betablocker in hypertensive patients.
The response of arterial pressure to an infusion of saralasin was compared to the effect of surgical correction of renal vascular lesions (3 to 6 months after surgery) in eleven patients whose hypertension was associated with uni or bilateral stenosis of renal artery. Saralasin was infused after four days of dietary sodium restriction (10--40 mEq/day). An excellent correlation (r = 0.83, p less than 0.005) between the effects of saralasin and surgery was obtained. There was no correlation between the response to saralasin or to surgery and the ratio of renal vein renin activities. It is suggested that saralasin may be a good tool for predicting the effect of surgery in renovascular hypertension, when infused in moderately sodium depleted patients.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The "effective" contribution of angiotensin II in blood pressure regulation was investigated in 6 patients on maintenance hemodialysis who were hypertensive at the time of the study (MAP 133 +/- 5 mmHg). Saralasin, a specific angiotensin II inhibitor, was infused at 0.5 and 2.5 microgram/kg/mn three hours before andone hour after hemodialysis. Before hemodialysis, a mean arterial pressure decrease of 13.2 to 19 p. 100 was obtained in 5 patients, arterial pressure being normalized in three of them. After hemodialysis, saralasin induced a normalization of arterial pressure in these 5 subjects. One patient, who was resistant to the saralasin infusion before and after the hemodialysis procedure, can be considered as purely volume-dependent. The renin-angiotensin system is probably one of the primary determinant of dialysis-resistant hypertension. However, a negative response to saralasin should encourage to control hypertension by more vigorous ultrafiltration during dialysis.
The effect of an angiotensin II antagonist (saralasin) on arterial pressure, plasma renin activity (PRA) and plasma aldosterone concentration (PAC) was assessed in seven dialysis-resistant hypertensive patients. During saralasin infusion performed before hemodialysis, mean arterial pressure fell by 8 to 18.3% in six out of the seven subjects; arterial pressure was normalized in three of them. After hemodialysis (6 subjects), a normal arterial pressure was achieved in five patients. One patient was resistant to saralasin before and after dialysis. A negative correlation (r = 0.62) was obtained between pre-infusion PRA and the change in mean arterial pressure induced by saralasin. Post-infusion PRA increased in saralasin responsive patients, the change in PRA being correlated (r = 0.82) with the pre-infusion PRA. Plasma aldosterone concentration was variably affected by saralasin; a negative correlation between pre-infusion PAC and the absolute change in PAC during saralasin was obtained (r = 0.72). The role of angiotensin II in the maintenance of a high arterial pressure in chronic dialysis patients was demonstrated. In saralasin-resistant patients, more vigorous ultrafiltration is proposed.
1. A P113 Saralasin infusion test was performed in 10 patients on long-term regular hemodialysis. Six patients were considered to have hypertension resistant to dialysis treatment and 4 had their arterial pressure controlled by dialysis. 2. Five out of 6 resistant and 3 out of 4 responsive patients had a positive response to Saralasin associated with a normalization of diastolic arterial pressure. 3. The value of the Saralasin infusion test to pre-select the patients for bilateral nephrectomy is discussed and it is felt that a negative test may be of more value in encouraging more aggressive ultrafiltration in hypertension apparently resistant to dialysis therapy.
Explore the source record for details and available documents.