The influence of dairy products on plasma uric acid in women.

Elevated levels of plasma uric acid have been linked to increased risk of cardiovascular diseases and their complications. As dairy proteins have been found to decrease plasma uric acid without increasing glomerular filtration rate, a sample of postmenopausal women living in Montreal was studied to investigate the nature of this relationship. Participants (158 Roman Catholic nuns) were randomly assigned to one of two test diets for a period of four weeks: the dairy foods group (n = 81) consumed approximately 30 grams of dairy protein daily and the dairy-free diet group (n = 77) ate no dairy foods at all. Subjects completed two one-day food records, a core questionnaire and a dairy foods diet history; blood specimens were obtained, and blood pressure, height and weight were measured. Average nutrient intakes differed as a consequence of the test diets, with significantly greater intakes of protein, fat, saturated fat, monounsaturated fat, potassium and calcium (p < 0.01) in the dairy group after the study period, and lower dietary levels of protein, cholesterol, calcium and retinol (p < 0.01) in the dairy-free group. Plasma uric acid was unchanged after the dietary intervention in the dairy group, but increased by 7.8 mumol/l (p = 0.03) in subjects on the dairy-free diet; however, diastolic blood pressure decreased in response to calcium (beta = -22.9, SE = 10.0, p = 0.02) among those whose diet included dairy foods.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of protein intake on glycaemic control and renal function in type 2 (non-insulin-dependent) diabetes mellitus.

Recent clinical investigations have suggested that dietary protein intake may modulate the progression of diabetic nephropathy and influence glycaemic control in Type 2 (non-insulin-dependent) diabetes mellitus. Twelve normotensive Type 2 diabetic patients with microalbuminuria took part in a randomized cross-over trial of a 3-week high protein diet (2.0 g/kg.desirable weight per day) and a 3-week moderate protein diet (0.8 g/kg desirable weight per day) to test the simultaneous effect of protein intake modulation on glycaemic control and renal function. Both diets were isoenergetic and the moderate protein diet was supplemented with calcium and phosphate. Renal function and glycaemic control were evaluated at the beginning and at the end of each diet. The moderate protein diet reduced the urinary albumin excretion rate, glomerular filtration rate, creatinine clearance, and proteinuria without adversely affecting glycaemic control; fasting glycaemia and the ratio of fructosamine to proteins were significantly reduced. The high protein diet induced similar improvements in glycaemic control but small changes in renal function.

Milk- and soy-protein ingestion: acute effect on serum uric acid concentration.

Acute effect of the ingestion of 80 g each of casein, lactalbumin, and soybean isolate on serum and urinary uric acid concentrations was investigated in 10 healthy subjects. Serum and urinary uric acid concentrations were measured before and after the ingestion of proteins. Serum uric acid decreased significantly 3 h after ingestion of lactalbumin and casein but increased after soybean consumption. Urate clearance was significantly increased after ingestion of each of the three proteins. Multivariate analysis of urate clearance during lactalbumin and casein loads showed that independent correlation was obtained for serum alanine and urea concentration. These results demonstrate that, in addition to their known uricosuric effect, milk proteins acutely decrease serum uric acid concentration. Analysis of the effects of lactalbumin and casein on urinary uric acid elimination suggests that the uricosuric effect of proteins is a multifactorial phenomenon.

The effect of Diamicron on the secretion and action of insulin.

We studied, in healthy subjects (n = 4) and in non-insulin-dependent diabetics (n = 4), the effect of a new sulfonylurea, Diamicron, on the secretion and action of insulin, using a mathematical model. This model analyzed, during an intravenous glucose tolerance test, the response of the first and second phase of insulin secretion in relation to the variations in blood glucose (insulin secretion) and the rate of decline in the blood glucose curve in relation to the variations in insulin (insulin response). Each subject was studied twice: once after administration of placebo and once after administration of Diamicron 80 mg 90 min after intravenous injection of 300 mg/kg of D-glucose. In healthy subjects, the glucose load after placebo induced an insulin response of 7.4 +/- 1.0 and 11.3 +/- 1.4 microU ml-1 min-1 mg-1 dl-1 for the first and second phases, respectively, and an insulin sensitivity evaluated to be 4.7 +/- 0.3 min microU-1 ml-1. Following the administration of Diamicron, the insulin response to the same glucose load increased two-fold and five-fold for the first and second phases, respectively, and the insulin sensitivity also increased by a factor of 2. In diabetic subjects the insulin response to the glucose load after placebo was markedly decreased (2.2 +/- 0.5 and 2.5 +/- 0.3 microU ml-1 min-1 mg-1 dl-1, respectively) as was the insulin sensitivity (2.5 +/- 0.3 min microU-1 ml-1). The administration of Diamicron increased all these parameters by a factor of 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Obesity, hypertension, hyperuricemia and diabetes mellitus among the Cree and Inuit of northern Québec.

In the last thirty years, sociocultural and political changes have profoundly affected the way of life of the Cree and Inuit of Northern Québec. Their health status profile has also changed. This study presents the main results of a health survey performed among the Cree and Inuit in 1982-1984 by a multidisciplinary team. Obesity, arterial hypertension, hyperuricemia and diabetes mellitus while almost unknown in the past, have now been added to the list of Cree and Inuit health problems. Crees have the highest risk for obesity, hypertension and diabetes mellitus. Hyperuricemia for unknown reasons seems more prevalent among the Inuit. Our findings suggest that further in-depth studies of chronic conditions in these communities are needed.

The genetic defect in multiple endocrine neoplasia type 2A maps next to the centromere of chromosome 10.

Multiple endocrine neoplasia type 2A (MEN2A) is a rare cancer syndrome that is inherited in an apparently autosomal dominant fashion. Previous linkage studies had assigned the MEN2A locus to chromosome 10 in the pericentromeric region. We recently have described several new easily scorable RFLPs for the chromosome 10-specific alpha satellite DNA (the D10Z1) locus that is known, on the basis of previous in situ hybridization experiments, to lie at the centromere. We report here tight linkage between MEN2A and D10Z1, as demonstrated by a maximum lod score of 12.02 at the recombination frequency of zero (1-lod-unit support interval 0-4 cM), indicating that the genetic defect in MEN2A lies in the immediate vicinity of the centromere. By means of a set of ordered polymorphic DNA markers from the pericentromeric region, multipoint as well as pairwise linkage analyses place the MEN2A locus at the middle of a small region (approximately 11 cM) bracketing the centromere with FNRB (at 10p11.2) and RBP3 (at 10q11.2) on either side, providing further support for the centromeric location of the MEN2A locus. Marked sex difference in recombination frequencies exists in this pericentromeric region: significantly (P less than .01) more female than male crossovers were observed across all of the adjacent intervals D10S24-FNRB, FNRB-D10Z1, and D10Z1-RBP3. However, a sex difference was not seen in the 7-cM interval from RBP3 to D10S5, suggesting that large variation in the sex difference in recombination can occur over small chromosomal regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification and localization of 7B2 protein in human, porcine, and rat thyroid gland and in human medullary carcinoma.

The novel, highly conserved polypeptide 7B2, which belongs to a new protein superfamily, was isolated from human and porcine hypophysis. The availability of a specific antibody to a synthetic fragment enabled 7B2 localization in a number of neurocrine and endocrine tissues and revealed its secretory character. 7B2 was purified from thyroid homogenates by HPLC chromatography and characterized by gel permeation chromatography (dimeric mol wt, approximately 40,000) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (monomeric mol wt, 20,750). By immunocytochemistry 7B2 was colocalized with calcitonin in parafollicular cells and identified within secretory granules by electron microscopy. Three of nineteen human medullary carcinoma cases showed immunoreactive 7B2 within the early and late hyperplasia stages and neoplasia. Results suggest that 7B2 may play a role in endocrine function, possibly as a secretory substance, and may be a histochemical marker in addition to calcitonin for medullary carcinoma.

Medullary thyroid carcinoma: localization of a mediastinal metastasis with I-131 MIBG.

An I-131 metaiodobenzylguanidine (MIBG) scan was performed in a patient with a familial history of multiple endocrine neoplasia (MEN) type 2 and recurrent medullary thyroid carcinoma (MTC). The scan revealed a mediastinal metastasis from her MTC and there was also an imaging pattern of bilateral adreno-medullary hyperplasia. Although the literature indicates that I-131-MIBG scanning is not sufficiently sensitive for the detection of MTC, this procedure has proven to be of value in the management of chosen patients with MEN-associated MTC.

Hypoglycemic effect of fenfluramine in insulin-treated diabetics.

In addition to its anorectic effect, fenfluramine has been demonstrated to decrease blood glucose levels in diabetics, independently of weight loss or the anorectic action. These studies have usually been performed in insulin-independent diabetics. We therefore undertook to investigate 8 non-insulin-dependent and 2 insulin-dependent patients receiving insulin, and noted a mean 21.1 +/- 3.8% decrease in blood glucose after 10 days of fenfluramine utilization. This parameter was diminished in all subjects in whom it had been elevated (greater than 120 mg/d1) during the placebo period of our double-blind, randomized study. Thus, fenfluramine apparently has the capacity to lower glucose in patients receiving insulin therapy.

Cimetidine and glucose tolerance (oral and intravenous).

In the intravenous glucose tolerance test (seven subjects) plasma glucose was not modified, but the insulin levels were lower 2 min after cimetidine was given. Cimetidine modified the oral glucose tolerance test in 13 subjects by increasing the glucose values after 60 min. Insulin levels at that time were also significantly higher. These findings support the hypothesis that cimetidine, an H2 antagonist, could alter glucose handling through its effect on histaminic fibers of the islets of Langerhans.

Carpenter's syndrome with empty sella and abnormal LRH and TRH response.

Two sisters with Carpenter's syndrome and empty sella have been evaluated for pituitary function. The TRH injection brought a normal response of TSH and prolactin. There were no change in FSH and LH, but a paradoxical increase of growth hormone and cortisol. The injection of LRH brought a normal response of FSH and LH, no change in TSH and cortisol values and a paradoxical increase in prolactin and growth hormone.

Fenfluramine in the treatment of non-insulin-dependent diabetics: hypoglycemic versus anorectic effect.

A few studies have suggested that the anorectic drug fenfluramine has a hypoglycemic effect. The major problem in interpreting those studies, however, is the difficulty in dissociating the effect of weight loss on blood glucose from the direct effect of fenfluramine. In a double-blind study of 28 diabetic females treated with oral hypoglycemic agents, a significant decrease in fasting blood glucose (from 195 +/- 17 mg/dl to 152 +/- 15 mg/dl after four weeks, and to 155 +/- 14 mg/dl after eight weeks) was observed in fenfluramine-treated patients (n = 14). Corresponding values in the placebo group were 185 +/- 12 mg/dl and 201 +/- 16 mg/dl respectively. Glucose tolerance after a standard meal was also improved after fenfluramine treatment. Weight loss was minimal and not significantly different for the two groups. From these observations, it can be concluded that fenfluramine has a lowering effect on blood glucose which is independent of its effect on weight.