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Dive into the research topics where David R. Pieper is active.

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Featured researches published by David R. Pieper.


Headache | 1996

The confirmation of a biochemical marker for women's hormonal migraine: the depo-estradiol challenge test.

Edward M. Lichten; Jason B. Lichten; Albert Whitty; David R. Pieper

Precis: Will estrogen withdrawal cause migraines in post‐menopausal women?


Annals of Plastic Surgery | 1989

Complications of reduction mammaplasty: comparison of nipple-areolar graft and pedicle.

David Hawtof; Michael Levine; Donald Kapetansky; David R. Pieper

A retrospective study of breast reductions in 268 patients by two plastic surgeons was performed. Particular attention was paid to those patients treated by inferior pedicle techniques; these patients were compared with those treated by free nipple grafts. According to our findings, patients with skin loss were heavier and had longer suprasternal notch-to-nipple distances. Patients who had free nipple grafts were older and heavier and had larger specimen weights and longer suprasternal notch-to-nipple distances. Fifty-four of the original 268 patients were included in a substudy of larger breasts, defined as those with a specimen weight of over 700 g. Nineteen patients underwent free nipple grafts, and 35 underwent inferior pedicle techniques. None of the 19 patients having free nipple grafts developed complications, whereas 6 of the 35 undergoing inferior pedicle techniques sustained significant complications. We conclude that free nipple grafts should be considered over inferior pedicles in heavier patients with breast ptosis.


Breast Cancer Research and Treatment | 1989

Tissue ferritin concentration and prognosis in carcinoma of the breast

Robert E. Weinstein; Bernice H. Bond; Boris Silberberg; Clarence B. Vaughn; Perla Subbaiah; David R. Pieper

SummarySeven year follow-up data were available on 36 of 40 breast carcinoma patients in whom breast tissue ferritin concentrations at the time of surgery were known. 18 patients were alive and free of recurrence or second tumor (Group 1) and 11 died with breast cancer (Group 2). Patients with lower tissue ferritin concentrations defined as < 319 ng/mcp (nanograms of ferritin/milligram of cytosol protein) were at reduced risk: 86% of patients with low tissue ferritin concentration survived free of recurrence or second tumor vs. 40% of patients with high tissue ferritin concentration (P = 0.0056). Mean breast carcinoma tissue ferritin concentration was 295 ± 52 ng/mcp in Group 1 and 444 ± 55 ng/mcp in Group 2 (P = 0.036).Lymph node involvement was predictive of mortality from breast carcinoma (P = 0.0003), but did not correlate with mean tissue ferritin concentration (P = 0.082). 10/10 (100%) patients who had both low tissue ferritin concentration and absence of lymph node involvement were in Group 1.The correlation of breast tissue ferritin concentration with histopathologic dedifferentiation and with prognosis suggests tumor tissue ferritin as a marker of malignant potential.


Experimental Biology and Medicine | 2000

Characterization of Serum Dehydroepiandrosterone Secretion in Golden Hamsters

David R. Pieper; Catherine Lobocki

Dehydroepiandrosterone (DHEA) is an adrenal androgen whose function is poorly understood. Although DHEA and DHEA sulfate (DHEAS) are secreted in relatively high quantities by the human adrenal, the laboratory rat secretes very little, thus hindering experimental studies of the hormone. In this paper, we measured the changes in serum DHEA and DHEAS under various physiological conditions in golden hamsters. Evening serum DHEAS fell from 6.30 +/- 0.78 microg/dl (mean +/- SE) before surgery to 3.03 +/- 0.23 microg/dl 12 days after bilateral adrenalectomy. Hamsters had higher levels of DHEA and DHEAS in the evening than in the morning, but removal of the gonads did not consistently decrease serum DHEA or DHEAS in males or females. Evening levels of DHEA and DHEAS reached a peak around 7 weeks of age and then gradually decreased to about one-third of these levels by one year of age. These results suggest that DHEA and DHEAS are secreted at least in part from the hamster adrenal, that they do not originate from the gonads, and that there is a daily rhythm with peak levels at a time of day just preceding the active phase. In addition, the levels of these hormones decrease with aging.


Journal of Neuroendocrinology | 1990

The Olfactory Bulbs Tonically Inhibit Serum Gonadotropin and Prolactin Levels in Male Hamsters on Long or Short Photoperiod

David R. Pieper; Catherine Lobocki; Melinda Thompson; Marappa G. Subramanian

Bilateral removal of the olfactory bulbs (BX) inhibits the testicular regression associated with maintenance of golden hamsters on short photoperiod (10L:14D). The present study was done to examine the reproductive endocrine changes following BX of hamsters, to test whether BX increases gonadotropin secretion by enhancing the rate of metabolism of peripheral testosterone, and to determine whether BX inhibits the response to photoperiod by blocking chemosensory signals from conspecifics.


Brain Behavior and Immunity | 1988

Altered cerebral dominance in an atopic population

Robert E. Weinstein; David R. Pieper

Handedness was assessed in 853 subjects, 424 from an allergy office practice and 429 from a health screening clinic, using a modified Oldfield Handedness Inventory. Subjects also responded to a survey ascertaining both personal and family histories of allergy-related problems and left-handedness. A significant left-handed shift in mean laterality quotient and an increased incidence of left-handedness was found in participants from the allergy office and in subjects who considered themselves to be affected by allergy, allergic rhinitis, and/or asthma. Controlling for nonatopic responders from the allergy office and possibly atopic responders from the health screening clinic, mean laterality quotients were 66.4 +/- 51.6 vs 79.4 +/- 42.1 (p less than .001) and the incidence of left-handedness was 12.1% vs 6.8% (p less than .05). Mean laterality quotient of 125 asthmatics was 65.1 +/- 54.0, and 16 (12.8%) were left-handed. The mean percentage of left-handed children of 79 asthmatic parents was found to be increased: 16.7 +/- 26.3% vs 10.3 +/- 21.2% of children of 198 nonatopic parents (p less than .02). This was attributable to left-handed children of asthmatic women, 18.6 +/- 29.0% (p less than .01), but not asthmatic men. Both autonomic neurologic dysfunction and disordered immunoregulation typify atopic disease. Our results can be interpreted to reflect this duality and lend support to Geshwinds hypothesis of a relationship between cerebral dominance and immunologic set resulting from common developmental influences.


Neuroendocrinology | 1987

Olfactory Bulbs Influence Testosterone Feedback on Gonadotropin Secretion in Male Hamsters on Long or Short Photoperiod

David R. Pieper; Phillip D. Unthank; Denise A. Shuttie; Catherine Lobocki; Jennifer M. Swann; Sara Newman; Marappa G. Subramanian

Previous studies have shown that prepubertal olfactory bulbectomy will prevent the testicular regression associated with short photoperiod in golden hamsters. The gonadal regression which normally occurs in hamsters on short photoperiod is known to be due in part to an increased responsiveness of the reproductive neuroendocrine system to the negative feedback actions of testosterone on LH and FSH secretion. The present study tested whether the olfactory bulbs influence the feedback effects of testosterone on gonadotropin secretion. Twenty-four- to 26-day-old male golden hamsters were either olfactory-bulbectomized (BX) or sham-olfactory-bulbectomized. Eight weeks later, all hamsters were castrated, and one half of each group was placed in LD 10:14 (this was called week-8 of the study), while the other half was returned to long photoperiod (LD 14:10). Eight weeks following castration (week 0 of the study), all animals were implanted with silastic capsules containing 0, 4, 8 or 16 mm of testosterone. All hamsters were bled by cardiac puncture at -8, -4, 0, +2, +4, +6 and +8 weeks. The concentration of LH and FSH in these samples was then determined by RIA. BX completely prevented the negative feedback of testosterone on gonadotropin secretion in hamsters on either long or short photoperiod at all levels of testosterone tested in this study. In addition, there were seemingly steroid-independent effects of BX on gonadotropin levels in the castrated hamsters prior to testosterone replacement at weeks -4 and 0.(ABSTRACT TRUNCATED AT 250 WORDS)


Brain Research | 1989

Bilateral transection of the lateral olfactory tract but not removal of the vomeronasal organs inhibits short-photoperiod-induced testicular regression in golden hamster

David R. Pieper; Sarah Winans Newman; Catherine Lobocki; Gabriel Gogola

It is now known that removal of the olfactory bulbs increases basal gonadotropin secretion and prevents short-photoperiod-induced testicular regression in Syrian hamsters. The experiments described in the present paper were an attempt to determine which neuronal systems associated with the olfactory bulbs are responsible for this influence on the reproductive neuroendocrine axis. In the first experiment, removal of the vomeronasal organ failed to influence gonadotropin secretion or testes weight in hamsters on long or short photoperiod, suggesting that the vomeronasal-accessory olfactory pathway is not individually responsible for the effect of the olfactory bulbs on gonadotropin secretion. In the second experiment, bilateral transection of the lateral olfactory tracts (LOT) did prevent short-photoperiod-induced testicular regression and the associated decrease in gonadotropin secretion. Since the nervus terminalis is confined to the surface of the medical olfactory bulb pathway, the results of LOT transection indicate that the nervus terminalis, which itself contains gonadotropin releasing hormone, does not mediate the influence of the olfactory bulbs on gonadotropin secretion. These results further suggest that the olfactory bulb influence on gonadotropin secretion is due to neural connections to the pyriform cortex, entorhinal cortex or amygdala.


The Journal of Allergy and Clinical Immunology | 1996

Decreased adrenal sex steroid levels in the absence of glucocorticoid suppression in postmenopausal asthmatic women

Robert E. Weinstein; Catherine Lobocki; Sharon Gravett; Hillman Hum; Ronald Negrich; Jonathan Herbst; Dana Greenberg; David R. Pieper

BACKGROUND AND AIM Reduction of serum sex steroid levels has been reported to occur after the administration of beta-adrenergic medication. In that beta-adrenergic blockade is a central pathophysiologic feature of asthma, this study was done to explore the possibility of hormonal alteration in asthma. METHODS Sex steroids obtained from 22 postmenopausal asthmatic and 22 age-matched, postmenopausal, nonasthmatic women were assayed. No subject had received estrogens, progestins, or oral corticosteroids for 120 days before the study. RESULTS Mean dehydroepiandrosterone sulfate (DHEAS; p < 0.002), dehydroepiandrosterone (DHEA; p < 0.03), estradiol (p < 0.02), and estrone (p < 0.02) levels were lower in asthmatic patients compared with nonasthmatic subjects. Results could not be accounted for by current medication. Patients with asthma demonstrated no decrease in 17-hydroxyprogesterone or cortisol compared with nonasthmatic subjects, limiting findings to the delta 5, and not the delta 4, steroidogenic pathway. In a second phase of the study, DHEAS was measured before and after 3 days of oral beta-agonist stimulation in eight postmenopausal asthmatic women. Serum DHEAS concentration increased in eight of eight subjects, from a mean of 28.6 +/- 19.9 micrograms/dl (mean +/- SD) to 40.7 +/- 24.8 micrograms/dl (p = 0.002). Serum cortisol concentration was unchanged. CONCLUSION The results indicate that postmenopausal asthmatic women have lower serum levels of adrenally derived sex steroids than their nonasthmatic peers and that this anomaly may be ameliorated by adrenergic stimulation.


Journal of Neuroendocrinology | 1990

The Olfactory Bulbs Enhance Reproductive Hormone Secretion in Male Rats on Long or Short Photoperiod

David R. Pieper; Catherine Lobocki; Melinda Thompson; Marappa G. Subramanian

Unlike seasonally breeding species such as the Syrian hamster, Sprague‐Dawley laboratory rats do not normally respond to short photoperiod (6L18D) with reproductive regression. However, removal of the olfactory bulbs (BX) unmasks a photoperiodic response in pre‐pubertal rats so that blinding or short photoperiod results in an inhibition of reproductive hormone secretion and/or a delay in pubertal development. This is apparently mediated by pineal melatonin which inhibits gonadotropin and/or prolactin secretion, but the mechanism by which BX facilitates the response to photoperiod is not clear.

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