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Biomedical subjects

S Epstein

Publications and source records attributed to S Epstein.

At least 199 records · Page 11Linked to original sources
PubMed1987

Deranged bone mineral metabolism in chronic alcoholism.

Chronic alcoholic subjects may suffer from osteopenia with either osteomalacia or osteoporosis as the main histologic finding. The reasons may be multifactorial, including nutrition, direct effects of alcohol on bone, and deranged liver function. Seventeen asymptomatic subjects with chronic alcoholism were studied. Serum PTH (carboxyl and midmolecule fragments), 25 hydroxyvitamin D [25(OH)D], 1-25 dihydroxyvitamin D [1-25(OH)2D], and ionized calcium were measured in each subject. In addition to these tests, we employed a sensitive technique of dual photon absorptiometry to measure vertebral bone density and a radioimmunoassay of serum bone gla protein (BGP) to estimate osteoblast function. Our results show that subjects suffering from chronic alcoholism had significantly lower serum 25(OH)D and higher ionized calcium, BGP, PTH (midmolecule) and 1,25(OH)2D while four patients had bone density values below the fracture threshold (0.96 g/cm2). These findings demonstrate that asymptomatic patients with chronic alcoholism have deranged bone mineral metabolism including abnormal BGP and some subjects may even have abnormal dual photon absorptiometry measurements. These particular subjects may be at risk in the future for developing osteopenia and consequent vertebral compression fractures.

Adult↗
PubMed1987

The relation of essential hypertension to feelings of anxiety, depression and anger.

Franz Alexander (1939) offered the hypothesis a number of years ago that hypertension can result from the inhibition of feelings of anger. Although a great deal of research has been done to test this hypothesis, the results remain equivocal. Part of the difficulty is that usually only anger was examined, making it impossible to determine the extent to which the results were specific to anger and not general for other negative emotions. A second prevalent problem has been the failure to match hypertensive and control groups on demographic variables that may be relevant to the relationship of hypertension to anger and its expression, such as education, economic level, and age. A third problem is that most studies have investigated only male hypertensives, thereby limiting the generality of the findings. The present study compares male and female hypertensives with carefully matched controls on measures of anxiety, depression, and anger and its suppression.

Adult↗
PubMed1987

1,25-Dihydroxyvitamin D3 modulates glucocorticoid-induced alteration in serum bone Gla protein and bone histomorphometry.

Glucocorticoid excess is associated with alterations in the vitamin D endocrine system. The aim of this study was to assess change in serum bone Gla protein (BGP) after low and high dose cortisone acetate treatment and to assess whether these alterations are altered or attenuated by 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] administration. Five groups of rats were studied and compared to a control group [cortisone acetate in doses of 0.2, 3.3, and 5.0 mg/100 g BW; 1,25-(OH)2D3 in a dose of 100 ng/100 g BW; and a combination of 1,25-(OH)2D3 (100 ng/100 g BW) plus cortisone acetate (3.3 mg/100 g BW)]. Each animal received daily sc injections for 27 days. BGP decreased significantly by day 7 in the two groups receiving high doses of cortisone acetate compared to control group values (65.20 +/- 4.38 vs. 150.18 +/- 6.13 ng/ml in the intermediate dose group and 91.57 +/- 5.30 vs. 150.18 +/- 6.13 ng/ml in the high dose group; P less than 0.01); this effect persisted until day 28. Histomorphometry revealed decreased formation and resorption in the two high dose cortisone acetate groups, whereas low dose cortisone acetate produced no histological change. The combination therapy lessens any change in BGP until day 28 when BGP was lower than the control value (P less than 0.01); histomorphometry showed that combination therapy prevents the effect of cortisone acetate by increasing bone formation and resorption. The data demonstrate that high doses of cortisone acetate suppress bone formation and that this is reflected in the low serum BGP values. Thus, BGP may be a marker of glucocorticoid-induced bone disease. 1,25-(OH)2D3 protects against glucocorticoid-induced bone disease and the normal BGP level reflects this.

Animals↗
PubMed1986

Commercializing university research. Lessons from the experience of the Wisconsin Alumni Research Foundation.

Universities that are now seeking ways to capture the financial rewards of advances made in biotechnology and other fields on their campuses have been encouraged by the apparent success of previous efforts to benefit from the commercial application of research findings by obtaining patents and granting licenses. Notable among these efforts is the Wisconsin Alumni Research Foundation (WARF). A close examination of the experience of this foundation reveals that, with good fortune and good management, a patenting and licensing organization can enjoy financial success. It also indicates, however, that the success experienced by WARF would be difficult to achieve today and that such efforts may yield lower financial returns than university administrators expect. Universities should be aware that such ventures entail financial risks and pose potential threats to traditional university values.

Academic Medical Centers↗
PubMed1986

Evidence that obesity does not influence the vitamin D-endocrine system in blacks.

As compared to nonobese white men and women, age-matched nonobese black subjects and obese white individuals show alterations in the vitamin D-endocrine system that are characterized by increases in mean serum immunoreactive parathyroid hormone (PTH), serum 1,25-dihydroxyvitamin D [1,25-(OH)2D], and urinary cyclic adenosine 3,5-monophosphate (cAMP) and by decreases in mean serum 25-hydroxyvitamin D (25 OHD) and in urinary calcium. Thus, both groups show secondary hyperparathyroidism which is associated with increased renal tubular reabsorption of calcium and increased renal synthesis of 1,25-(OH)2D. In view of these findings, studies were conducted in 10 obese black subjects (3 men and 7 women) and in 12 nonobese black individuals (7 men and 5 women), ranging in age from 20 to 35 yr, to determine whether obesity influences the vitamin D-endocrine system in blacks. Body weight averaged 99 +/- 4 kg in the obese and 73 +/- 3 kg in the nonobese subjects (p less than .001). All of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium, 900 mg of phosphorus, 110 meq of sodium, 65 meq of potassium, and 18 meq of magnesium.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Serum bone gla protein (BGP) and other markers of bone mineral metabolism in postmenopausal osteoporosis.

Bone gla protein, the vitamin K-dependent protein synthesized by osteoblasts and measured in blood by radioimmunoassay, has been used as an index of the rate of bone turnover. The relationship of bone gla protein with other markers of bone mineral metabolism was determined in 31 untreated postmenopausal women with the osteoporotic syndrome. In addition to serum osteocalcin (BGP) we measured parathyroid hormone (PTH) (carboxyl and mid-molecule fragments), 25(OH)D, alkaline phosphatase, estradiol (E2), estrone (E1), dietary calcium intake, 24 hour urinary calcium excretion, and bone mineral density by CT scan of the lumbar vertebrae. Significant osteopenia was present on CT in untreated postmenopausal osteoporotic women (bone density in 18 out of 31 was below the critical value of 60 mg/cm3). Serum BGP correlated positively with CT scan (r + 0.647, P less than 0.001). CT and age were negatively correlated (r - 0.661, P less than 0.001) while CT and E2 showed a positive correlation (r + 0.554, P less than 0.01). Unexpectedly, BGP and age revealed a significant negative correlation (r - 0.421, P less than 0.05). These findings suggest a state of low bone turnover in this group with untreated postmenopausal osteoporosis.

Adult↗
PubMed1986

The influence of age on bone mineral regulating hormones.

The objective of this study was to determine the effect of age on the blood levels of 1,25-dihydroxyvitamin D (1,25(OH)2D) and immunoreactive parathyroid hormone (iPTH) in normal, healthy males and females. A total of 855 normal subjects (361 males and 494 females) were studied. The results show that for healthy males, blood concentrations of 1,25(OH)2D remained essentially constant with increasing age up to age 65, and then the concentrations decreased significantly. For healthy females, 1,25(OH)2D increased up to age 65, and then decreased at a significant rate. Serum iPTH in males increased with advancing age, but the rate of increase was greater after age 65. In females a significant increase in iPTH concentrations did not occur until after age 65. Serum creatinine increased in both males and females with advancing age.

Adult↗
PubMed1986

Perception of cross-situational consistency.

Eighty-eight undergraduates rated the degree of relation in each of 21 pairs of items that described behavior in the domains of conscientiousness, friendliness, and extraversion. In these three domains, estimates of relations by the average subject correlated, respectively, with actual empirical relations, .63, .58, and .40. Relations corresponding to correlations between .10 to .20 could be significantly distinguished by subjects from relations in the range of .00 to .10 in two of the three domains. The confidence that individuals placed in their perceptions varied directly with the accuracy of their judgments against the empirical criterion. In addition, subjects were more confident of what they perceived to be extreme relations in both directions than of intermediate relations, and they also tended to be more confident of their judgments of strong positive relations than of zero relations. They exhibited an intuitive awareness of the effect of aggregation over occasions and items of behavior on the magnitude of cross-situational relations and the demonstration of traits. They also reported using reasonable strategies in arriving at decisions. Far from being inveterate trait believers, as some have suggested, subjects' intuitions paralleled psychometric principles in several important respects when assessing relations between real-life behaviors.

Adult↗
PubMed1986

Does aggregation produce spuriously high estimates of behavior stability?

A number of arguments as to why aggregation produces spurious correlations are considered and shown to be specious. A series of computer-simulated studies, claimed by H. D. Day and his colleagues to demonstrate that aggregation produces artifactually high stability coefficients, was shown to involve bizarre distributions and inappropriate conclusions. Nevertheless, their data actually indicated the potency of aggregation in detecting whatever empirical relations they built into their data. This was not true of their analyses of their unaggregated data, which, as a result of a high level of noise of measurement, failed to enable them to detect anomalies in their data. No amount of aggregation produced evidence of stability in its absence. It is concluded that aggregation provides a powerful tool for reducing error of measurement and for establishing and enhancing generality as well as stability in measurement. Although there is nothing intrinsic in aggregation that fosters spurious correlations, it like any other technique can be used wisely or foolishly. In order to achieve the former, aggregation must be guided by psychometric principles and theoretical considerations. A procedure guaranteed to achieve the latter is to simply aggregate whatever can be assigned a common label.

Computers↗
PubMed1985

Personality variables and metabolic control in children with diabetes.

Insulin-dependent diabetic children and a group of their nondiabetic peers were compared on measures of self-concept, locus of control and health locus of control. A metabolic measure of long term diabetes control was also obtained on the children with diabetes. Data analyses revealed that metabolic control was not related to any of the personality measures in the diabetic sample. Diabetic and non-diabetic children did not differ on measures of locus of control and self-concept, but diabetics exhibited a health locus of control which was significantly more internal than that of control subjects. A possible explanation for these results was discussed and practical implications for health care providers working with young diabetics were presented.

Adolescent↗
PubMed1985

Evidence for alteration of the vitamin D-endocrine system in obese subjects.

Serum immunoreactive parathyroid hormone (PTH) is increased in obese as compared with nonobese subjects and declines with weight loss. To determine whether alteration of the vitamin D-endocrine system occurs in obesity and whether ensuing secondary hyperparathyroidism is associated with a reduction in urinary calcium, a study was performed in 12 obese white individuals, five men and seven women, and 14 nonobese white subjects, eight men and six women, ranging in age from 20 to 35 yr. Body weight averaged 106 +/- 6 kg in the obese and 68 +/- 2 kg in the nonobese subjects (P less than 0.01). Each of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium and 900 mg of phosphorus. Whereas mean serum calcium, serum ionized calcium, and serum phosphorus were the same in the two groups, mean serum immunoreactive PTH (518 +/- 48 vs. 243 +/- 33 pg/ml, P less than 0.001), mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] (37 +/- 2 vs. 29 +/- 2, P less than 0.01), and mean serum Gla protein (33 +/- 2 vs. 24 +/- 2 ng/ml, P less than 0.02) were significantly higher, and mean serum 25-hydroxyvitamin D (25-OHD) (8 +/- 1 vs. 20 +/- 2 ng/ml, P less than 0.001) was significantly lower in the obese than in the nonobese men and women. Mean urinary phosphorus was the same in the two groups, whereas mean urinary calcium (115 +/- 10 vs. 166 +/- 13 mg/d, P less than 0.01) was significantly lower, and mean urinary cyclic AMP (3.18 +/- 0.43 vs. 1.84 +/- 0.25 nM/dl GF, P less than 0.01) and creatinine clearance (216 +/- 13 vs. 173 +/- 6 liter/d, P less than 0.01) were significantly higher in the obese than in the nonobese individuals. There was a significant positive correlation between percentage of ideal body weight and urinary cyclic AMP (r = 0.524, P less than 0.01) and between percentage of ideal body weight and serum immunoreactive PTH (r = 0.717, P less than 0.01) in the two groups. The results provide evidence that alteration of the vitamin D-endocrine system in obese subjects is characterized by secondary hyperparathyroidism which is associated with enhanced renal tubular reabsorption of calcium and increased circulating 1,25(OH)2D. The reduction of serum 25-OHD in them is attributed to feedback inhibition of hepatic synthesis of the precursor by the increased serum 1,25(OH)2D.

Adult↗
PubMed1985

Evidence for alteration of the vitamin D-endocrine system in blacks.

As compared with values in white subjects, bone mass is known to be increased and urinary calcium to be diminished in black individuals. To evaluate the possibility that these changes are associated with alterations in the vitamin D-endocrine system, an investigation was performed in 12 black subjects, 7 men and 5 women, and 14 white subjects, 8 men and 6 women, ranging in age from 20 to 35 yr. All of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium, 900 mg of phosphorus, and 110 meq of sodium. Whereas mean serum calcium, ionized calcium, and phosphate were the same in the two groups, mean serum immunoreactive parathyroid hormone (350 +/- 34 vs. 225 +/- 26 pg/ml, P less than 0.01) and mean serum 1,25-dihydroxyvitamin D (1,25(OH)2D) (41 +/- 3 vs. 29 +/- 2 pg/ml, P less than 0.01) were significantly higher, and mean serum 25-hydroxy-vitamin D (25-OHD) was significantly lower in the blacks than in the whites (6 +/- 1 vs. 20 +/- 2 ng/ml, P less than 0.001). Mean urinary sodium and 24-h creatinine clearance were the same in the two groups, whereas mean urinary calcium was significantly lower (101 +/- 14 vs. 166 +/- 13 mg/d, P less than 0.01) and mean urinary cyclic AMP was significantly higher (3.11 +/- 0.47 vs. 1.84 +/- 0.25 nM/dl glomerular filtrate, P less than 0.01) in the blacks. Further, the blacks excreted an intravenous calcium load, 15 mg/kg body weight, as efficiently as the whites (49 +/- 3 vs. 53 +/- 3%, NS). Mean serum Gla protein was lower in blacks than in whites (14 +/- 2 vs. 24 +/- 3 ng/ml, P less than 0.02), and increased significantly in both groups in response to 1,25(OH)2D3, 4 micrograms/d for 4 d. There was a blunted response of urinary calcium to 1,25(OH)2D3 in the blacks, and mean serum calcium did not change. The results indicate that alteration of the vitamin D-endocrine system with enhanced renal tubular reabsorption of calcium and increased circulating 1,25(OH)2D as a result of secondary hyperparathyroidism may contribute to the increased bone mass in blacks. Their low serum 25-OHD is attributed to diminished synthesis of vitamin D in the skin because of increased pigment.

Adult↗
PubMed1985

A prospective study of bone mass in patients with type I diabetes.

Sixty-nine patients with type I diabetes mellitus were followed for from 1-4 yr (mean, 3 yr). Their overall growth, as measured by height and weight, was normal; however, repeated measurements of their bone mass using photon absorptiometry and radiogrammetry showed that, relative to normal subjects, the patients had a persistent bone deficit throughout the course of the study. This deficit was not attributable to bone width, which was normal. On the average, the magnitude of the deficit did not change with time; furthermore, an individual's rate of change in bone mass deficit during the study was not correlated with the patient's glucose control, as measured by hemoglobin A-1 or fasting blood glucose levels. Initial levels of serum ionized calcium and magnesium were decreased in the patients with diabetes. During the study, the mean level of ionized calcium increased, but that of magnesium decreased further, compared to the initial values. In a group of 19 patients with newly diagnosed diabetes, bone mass was found to be significantly below normal among the girls, but not among the boys.

Adolescent↗
PubMed1985

Serum and dialysate osteocalcin levels in hemodialysis and peritoneal dialysis patients and after renal transplantation.

Serum osteocalcin (BGP), a vitamin K-dependent gamma-carboxyglutamic acid (GLA) containing bone protein, provides an index of bone turnover in patients with a variety of metabolic bone diseases. BGP increases with increasing age in both sexes, but more so in women. BGP rises above normal when the glomerular filtration rate falls below 30 ml/min. Because of its importance in bone disease, its low mol wt, and the effect of uremia, we measured BGP by RIA in serum and dialysate fluid in patients on hemodialysis (HD) or peritoneal dialysis (PD). In 32 HD patients (22 women and 10 men), serum BGP was not different pre- and postdialysis [67.5 +/- 4.4 (+/- SEM) ng/ml vs. 67.7 +/- 5.2), but was significantly elevated compared to the level in normal subjects (7.3 +/- 0.8 ng/ml). The sex difference previously reported in normal subjects was not found in patients with renal failure. The serum BGP level in 8 PD patients was 49.4 +/- 6.9 ng/ml, with a peritoneal fluid concentration of 27.6 +/- 9.3 ng/ml. The hemodialysate fluid concentration of BGP was 1.7 +/- 0.4 ng/ml, which was significantly lower than the serum BGP levels in the HD patients, the PD patients, and peritoneal fluid (P less than 0.01). A significant correlation existed among BGP, alkaline phosphatase, immunoreactive PTH, creatinine, and blood urea nitrogen. We conclude that BGP is markedly elevated in patients with renal failure, not altered in the serum by HD or PD, but very low in HD dialysate fluid. These findings may reflect a combination of impaired clearance and increased skeletal production. The difference in clearance between the peritoneal and hemodialysis fluid is compatible with the mol wt of BGP. In 15 patients who had successful kidney transplantation, serum BGP was normal despite an elevated serum PTH level.

Alkaline Phosphatase↗