David B. Endres

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Over the last few years, awareness of autism spectrum disorder (ASD) in adults has increased. The precise etiology of ASD is still unresolved. Animal research, genetic and postmortem studies suggest that the glutamate (Glu) system has an important role, possibly related to a cybernetic imbalance between neuronal excitation and inhibition. To clarify the(More)
The effects of chronic GH and insulin-like growth factor-I (IGF-I) excess on bone metabolism were examined by measuring serum markers of bone formation and urine markers of bone resorption as well as vertebral bone densities in patients with active acromegaly. Fasting serum GH levels were elevated in all 27 patients (31 +/- 11 micrograms/L). Serum calcium(More)
Circulating levels of PTH and related parameters of calcium and phosphate metabolism were measured in healthy free-living elderly and young subjects residing in the Southwest to determine if parathyroid function changes with aging. Serum immunoreactive PTH (iPTH) was measured with two well characterized antisera; an amino (N)-terminal antiserum which(More)
This study evaluated basal levels and responsiveness to exercise of plasma adrenocorticotropic hormone (ACTH), and serum thyroid stimulating hormone (TSH), growth hormone (GH) and cortisol among adolescents from two differentially exposed groups 6 1/2 years after the 1988 earthquake in Armenia. Severity of total PTSD and Category C and D symptoms were(More)
Twenty-seven asymptomatic patients treated with hemodialysis longer than 8 years (mean 12.9 +/- 3.1 years) underwent bone biopsy to determine the prevalence of aluminum-associated bone disease. None had excess aluminum exposure from the dialysate. Ten patients (37%) had aluminum-associated bone disease as defined by a bone formation rate (BFR) below normal(More)
We have examined the changes in bone histology in 28 uremic patients after long-term treatment with the aluminum chelator, deferoxamine. Marked declines in stainable bone-surface aluminum were associated with increases in bone formation rate and osteoblastic osteoid following deferoxamine. The increased bone formation resulted from increases in bone(More)
The effect of magnesium deficiency on vitamin D metabolism was assessed in 23 hypocalcemic magnesium-deficient patients by measuring the serum concentrations of 25-hydroxyvitamin D (25OHD) and 1,25-dihydroxyvitamin D [1,25-(OH)2D] before, during, and after 5-13 days of parenteral magnesium therapy. Magnesium therapy raised mean basal serum magnesium [1.0(More)
Magnesium (Mg) deficiency in man may result in hypocalcemia, impaired PTH secretion, and low serum concentrations of 1,25-dihydroxyvitamin D [1,25-(OH)2D]. To determine whether these changes are due to selective Mg depletion, we studied 26 normal subjects before and after a 3-week low Mg (less than 1 meq/day) diet. This diet induced Mg deficiency, as(More)
Plasma PTH concentrations were determined in rats with an antiserum to human PTH (1-34) that cross reacts with rat PTH in order to evaluate the effects of growth, vitamin D deficiency and dietary modulations of plasma calcium. Displacement curves for synthetic rat PTH (1-34) and diluted rat plasma were parallel with curves for the hPTH (1-34) standards and(More)
Bone biopsies were studied in 67 dialysis patients to determine if a PTH RIA specific for intact plasma PTH is a better predictor of osteitis fibrosa than a RIA that measures inactive carboxy-terminal/midregion plasma PTH fragments. An amino-terminal-specific antiserum that cross-reacts with intact PTH, but not midregion or carboxy-terminal fragments, and(More)