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N Lavin

Publications and source records attributed to N Lavin.

8 recordsLinked to original sources
PubMed1982

Urinary and serum steroid concentrations in the management of congenital adrenal hyperplasia. Lack of physiologic correlations.

Serum concentrations of 17-hydroxyprogesterone, dehydroepiandrosterone, dehydroepiandrosterone sulfate, progesterone, testosterone, and androstenedione and 24-hour excretion of 17-ketosteroids and pregnanetriol were measured serially in 18 children with congenital adrenal hyperplasia (21-hydroxylase deficiency) during a two-year period. Correlations were sought between results of measurements of these steroids and clinical progress assessed by physical examination and skeletal maturity to determine if measurement of concentration of these substances at a single point in time could be used to gauge the dose of corticosteroids for optimum treatment. We found that these measurements of steroids were generally not useful indicators of optimum control of the disease. Repeated careful clinical examination and assessment of changes in growth velocity and skeletal maturation seem to be the best criteria on which to base dosage of corticosteroids used for therapy.

17-Ketosteroids↗
PubMed1978

Management of congenital adrenal hyperplasia using serum dehydroepiandrosterone sulfate and 17-hydroxyprogesterone concentrations.

Simultaneous serum concentrations of dehydroepiandrosterone sulfate (DHEA-S) and 17-hydroxyprogesterone (17-OHP) were compared with urinary 17-ketosteroid (17-KS) and pregnanetriol (PT) excretion during therapy in 18 prepubertal patients with the 21-hydroxylase deficiency form of congenital adrenal hyperplasia (CAH). Patients were classified into those in good, poor, or questionable control on the basis of clinical examination, skeletal age, and 17-KS and PT excretion. During therapy, use of serum steroid concentrations was found to be nearly as accurate in judging adequacy of control as use of urine steroid concentrations. Of 34 evaluations, a definite assessment of adequacy of control could be arrived at 25 times using urinary values and 22 times using both serum DHEA-S and 17-OHP concentrations. DHEA-S concentration responded sluggishly when treatment was not adequate, being greater than 100 microgram/dl only in patients significantly undertreated. It was never elevated in well-controlled patients. Mid-afternoon 17-OHP concentrations were less than 200 ng/dl in well-controlled patients but readily escaped suppression and could not be used to differentiate poor from borderline control or from temporary noncompliance. Therefore, an increases DHEA-S concentration indicated poor control and a suppressed 17-OHP concentration indicated good control. The combination of normal DHEA-S level with elevated 17-OHP level, however, did not permit exact evaluation of the degree of control. Of significance is that not all patients with CAH present with an elevated DHEA-S concentration, and only in those in whom an elevated level has been documented can DHEA-S level be used as an index of control during therapy.

17-Ketosteroids↗
PubMed1976

An action of disodium cromoglycate: inhibition of cyclic 3',5'-AMP phosphodiesterase.

Disodium cromoglycate (DSCG) prevents allergic asthma by inhibiting the release of chemical mediators of immediate-type allergic reactions. The mechanism of this action is unclear and prompted us to examine the effect of DSCG on cyclic adenosine 3',5'-monophosphate (cAMP), the implicated regulator of IgE-mediated reactions. We used the peripheral blood lymphocyte as a model to mirror the biochemical events occurring in the allergic shock organs. Isolated peripheral blood lymphocytes from perennial allergic asthmatic children receiving only DSCG had significantly (p less than 0.005) lower phosphodiesterase (PDE) activity (mean 1.05 +/- 0.17 SE per 10(6) cells) than normal individuals (2.93 +/- 0.14) and allergic children receiving methylxanthines (4.08 +/- 0.28) or no medications (3.58 +/- 0.2). DSCG (10 mug/ml) significantly lowered PDE activity in normal lymphocytes (p less than 0.005) in a beef heart extract (p less than 0.001), and 100 mug/ml lowered PDE activity in fetal rabbit lung homogenates (p less than 0.001). DSCG (10 mug/ml) significantly elevated (p less than 0.01) cAMP concentration in normal human lymphocytes (118 +/- 38 vs 30 +/- 10 picomoles cAMP/10(6) lymphocytes). Thus, DSCG appears to inhibit chemical mediator release by increasing intracellular cAMP through the inhibition of cAMP PDE.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1976

Role of adenosine 3', 5'-monophosphate in maturation of fetal lungs.

Fetal lung cyclic AMP phosphodiesterase, cyclic AMP, phosphatidyl choline, and incorporation of precursors into phosphatidyl choline were measured in rabbits after maternal administration of hydrocortisone phosphate and aminophylline. Both agents inhibited lung phosphodiesterase activity and augmented cyclic AMP concentrations (Table 1). Aminophylline administration was associated with a significant increase in lung saturated phosphatidyl choline (Table 2). Incorporation of [14C] choline and [3H] methionine was increased by both aminophylline and hydrocortisone (Table 3).

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1975

Reversible hypothyroidism in growth hormone-deficient children treated with human growth hormone.

Six children with human growth hormone (hGH) deficiency became hypothyroid during the course of their therapy with hGH. This was accompanied by a decreasing growth rate, clinical symptoms of hypothyroidism and decreased serum T4 concentrations. Three of the 6 patients returned to the euthyroid state, both clinically and biochemically, with cessation of hGH therapy, and reinstitution of hGH precipitated hypothyroidism again in 2 of the three. The patients who remained hypothyroid have evidence of multiple pituitary trophic hormone deficiencies while those who reverted to euthyroidism appear to have isolated hGH deficiency. Evaluation of thyroid function while on hGH showed low T4, free T4 and T3 concentrations. The serum thyrotropin (TSH) response to thyrotropin-releasing hormone (TRH) was absent or markedly blunted in 4 of 6 patients while receiving long-term hGH therapy but was normal or exaggerated in all patients when tested before or after only 5 days of hGH therapy. These data indicate that exogenous hGH results in an inhibition of the TSH response to TRH. The mechanism of this inhibition is unclear, but we postulate that it may be mediated by somatostatin secretion in response to pulse doses of hGH.

Age Determination by Skeleton↗
PubMedDate not supplied

Factors affecting student program and career selection.

This study uses a national sample of freshman radiography students to examine demographic data and factors that affected career and program choice. The data are discussed in terms of implications for marketing and recruitment strategies.

Adolescent↗