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Featured researches published by Bonny Specker.


The New England Journal of Medicine | 1994

Estrogen Resistance Caused by a Mutation in the Estrogen-Receptor Gene in a Man

Eric P. Smith; Jeffrey E. Boyd; Graeme R. Frank; Hiroyuki Takahashi; Robert M. Cohen; Bonny Specker; Timothy C. Williams; Dennis B. Lubahn; Kenneth S. Korach

BACKGROUND AND METHODS Mutations in the estrogen-receptor gene have been thought to be lethal. A 28-year-old man whose estrogen resistance was caused by a disruptive mutation in the estrogen-receptor gene underwent studies of pituitary-gonadal function and bone density and received transdermal estrogen for six months. Estrogen-receptor DNA, extracted from lymphocytes, was evaluated by analysis of single-strand-conformation polymorphisms and by direct sequencing. RESULTS The patient was tall (204 cm [80.3 in.]) and had incomplete epiphyseal closure, with a history of continued linear growth into adulthood despite otherwise normal pubertal development. He was normally masculinized and had bilateral axillary acanthosis nigricans. Serum estradiol and estrone concentrations were elevated, and serum testosterone concentrations were normal. Serum follicle-stimulating hormone and luteinizing hormone concentrations were increased. Glucose tolerance was impaired, and hyperinsulinemia was present. The bone mineral density of the lumbar spine was 0.745 g per square centimeter, 3.1 SD below the mean for age-matched normal women; there was biochemical evidence of increased bone turnover. The patient had no detectable response to estrogen administration, despite a 10-fold increase in the serum free estradiol concentration. Conformation analysis of his estrogen-receptor gene revealed a variant banding pattern in exon 2. Direct sequencing of exon 2 revealed a cytosine-to-thymine transition at codon 157 of both alleles, resulting in a premature stop codon. The patients parents were heterozygous carriers of this mutation, and pedigree analysis revealed consanguinity. CONCLUSIONS Disruption of the estrogen receptor in humans need not be lethal. Estrogen is important for bone maturation and mineralization in men as well as women.


Cancer | 1998

Prospective multicenter study of thyroid carcinoma treatment initial analysis of staging and outcome

Steven I. Sherman; D M B James Brierley; Matthew Sperling; Kenneth B. Ain; S. Thomas Bigos; David S. Cooper; Bryan R. Haugen; Mona Ho; Irwin Klein; Paul W. Ladenson; Jacob Robbins; Douglas S. Ross; Bonny Specker; Terry Taylor; Harry R. Maxon

A novel prognostic staging classification encompassing all forms of thyroid carcinoma was created for the National Thyroid Cancer Treatment Cooperative Study (NTCTCS) Registry, with the goal of prospective validation and comparison with other available staging classifications.


Journal of Bone and Mineral Research | 2003

Randomized Trial of Physical Activity and Calcium Supplementation on Bone Mineral Content in 3- to 5-Year-Old Children

Bonny Specker; Teresa Binkley

A meta‐analysis of adult exercise studies and an infant activity trial show a possible interaction between physical activity and calcium intake on bone. This randomized trial of activity and calcium supplementation was conducted in 239 children aged 3‐5 years (178 completed). Children were randomized to participate in either gross motor or fine motor activities for 30 minutes/day, 5 days per week for 12 months. Within each group, children received either calcium (1000 mg/day) or placebo. Total body and regional bone mineral content by DXA and 20% distal tibia measurements by peripheral quantitative computed tomography (pQCT) were obtained at 0 and 12 months. Three‐day diet records and 48‐h accelerometer readings were obtained at 0, 6, and 12 months. Higher activity levels were observed in gross motor versus fine motor activity groups, and calcium intake was greater in calcium versus placebo (1354 ± 301 vs. 940 ± 258 mg/day, p < 0.001). Main effects of activity and calcium group were not significant for total body bone mineral content or leg bone mineral content by DXA. However, the difference in leg bone mineral content gain between gross motor and fine motor was more pronounced in children receiving calcium versus placebo (interaction, p = 0.05). Children in the gross motor group had greater tibia periosteal and endosteal circumferences by pQCT compared with children in the fine motor group at study completion (p < 0.05). There was a significant interaction (both p ≤ 0.02) between supplement and activity groups in both cortical thickness and cortical area: among children receiving placebo, thickness and area were smaller with gross motor activity compared with fine motor activity, but among children receiving calcium, thickness and area were larger with gross motor activity. These findings indicate that calcium intake modifies the bone response to activity in young children.


The New England Journal of Medicine | 1997

THE EFFECT OF CALCIUM SUPPLEMENTATION ON BONE DENSITY DURING LACTATION AND AFTER WEANING

Heidi J. Kalkwarf; Bonny Specker; Donna C. Bianchi; Julie Ranz; Mona Ho

BACKGROUND Women may lose bone during lactation because of calcium lost in breast milk. We studied whether calcium supplementation prevents bone loss during lactation or augments bone gain after weaning. METHODS We conducted two randomized, placebo-controlled trials of calcium supplementation (1 g per day) in postpartum women. In one trial (the study of lactation), 97 lactating and 99 nonlactating women were enrolled a mean (+/-SD) of 16+/-2 days post partum. In the second trial (the study of weaning), 95 lactating women who weaned their infants in the 2 months after enrollment and 92 nonlactating women were enrolled 5.6+/-0.8 months post partum. The bone density of the total body, lumbar spine, and forearm was measured at enrollment and after three and six months. RESULTS The bone density of the lumbar spine decreased by 4.2 percent in the lactating women receiving calcium and by 4.9 percent in those receiving placebo and increased by 2.2 and 0.4 percent, respectively, in the nonlactating women (P<0.001 for the effect of lactation; P= 0.01 for the effect of calcium). After weaning, the bone density of the lumbar spine increased by 5.9 percent in the lactating women receiving calcium and by 4.4 percent in those receiving placebo; it increased by 2.5 and 1.6 percent, respectively, in the nonlactating women (P<0.001 for the effects of lactation and calcium). There was no effect of either lactation or calcium supplementation on bone density in the forearm, and there was no effect of calcium supplementation on the calcium concentration in breast milk. CONCLUSIONS Calcium supplementation does not prevent bone loss during lactation and only slightly enhances the gain in bone density after weaning.


Obesity | 2006

Influence of parents' eating behaviors and child feeding practices on children's weight status

Darcy L. Johannsen; Neil Johannsen; Bonny Specker

Objective: To investigate the effects of mothers’ and fathers’ eating behaviors, child feeding practices, and BMI on percentage body fat and BMI in their children.


Obstetrics & Gynecology | 1995

Bone mineral loss during lactation and recovery after weaning.

Heidi J. Kalkwarf; Bonny Specker

Objective To test the hypothesis that bone mineral content (BMC) and density (BMD) are lost during lactation and regained within 6 months after weaning. Methods Two cohorts of women, defined by time postpartum, were enrolled into the study; each cohort was followed for 6 months. Women in the lactation cohort (65 lactating women and 48 nonlactating postpartum controls) were enrolled at 2 weeks postpartum. Women in the weaning cohort (40 lactating and 43 nonlactating postpartum controls) were enrolled at 4–6 months postpartum. Lactating women enrolled in the weaning cohort had been fully breast-feeding at enrollment and weaned within 2 months of enrollment. Bone mineral content of the total body and BMD of the lumbar spine and distal radius were measured by dualenergy x-ray absorptiometry. Results Lactating women lost significantly more bone in the total body (−2.8 versus −1.7%) and lumbar spine (−3.9 versus 1.5%) than did nonlactating women during the first 6 months postpartum. There was no effect of lactation on bone changes at the distal radius. After weaning, lactating women gained significantly more bone in the lumbar spine than did nonlactating women (5.5 versus 1.8%). Earlier resumption of menses was associated with a smaller loss of bone during lactation and a greater increase of bone after weaning. Conclusion Women lose bone during lactation but gain bone after weaning. Thus, lactation may not result in net bone loss.


Annals of Internal Medicine | 1998

Outcome after Treatment of High-Risk Papillary and Non-Hurthle-Cell Follicular Thyroid Carcinoma

Terry Taylor; Bonny Specker; Jacob Robbins; Matthew Sperling; Mona Ho; Kenneth B. Ain; S. Thomas Bigos; Jim Brierley; David A. Cooper; Bryan R. Haugen; Ian D. Hay; Vicki S. Hertzberg; Irwin Klein; Herbert A. Klein; Paul W. Ladenson; Ronald H. Nishiyama; Douglas S. Ross; Steven I. Sherman; Harry R. Maxon

The treatment of thyroid cancer has been investigated extensively, but disagreement remains about the degree of aggressiveness needed in its management. Despite the general perception that the prognosis is excellent, 9% of patients with thyroid cancer die of the disease [1]. Patients with the less differentiated types of thyroid cancer or those presenting at a more advanced stage face higher mortality rates [2, 3]. In addition, the recurrence rate after surgery is more than 20% in persons with differentiated thyroid cancer [2]. Therefore, the ability to define the most effective therapeutic interventions on the basis of patient stratification by histologic type and stage of cancer at initial presentation should improve survival and decrease recurrence rates. The initial treatment for thyroid cancer is surgery, but the extent of surgery needed to improve outcome remains controversial [4-6]. Some studies have shown that more extensive thyroid resection reduces the recurrence rate but has a less definite effect on survival [2, 7]. More extensive surgery may be associated with a higher prevalence of complications, usually hypoparathyroidism or recurrent laryngeal nerve damage (or both), in 3% to 15% of patients [8-10]. The indications for postoperative ablative radioiodine therapy and the required administered activity are also under debate. Multifocality and lymph node involvement at presentation in 46% of persons with papillary thyroid cancer (of whom 25% face persistent or recurrent disease) argue in favor of this therapy [2, 11, 12], despite the risk for sialoadenitis, gastrointestinal symptoms, occasional bone marrow suppression, and possible second cancers [13]. The role of external radiation in the treatment of differentiated thyroid cancer is also highly controversial. Increased recurrence [14], no therapeutic benefit [15-17], and improved local control [18, 19] have all been reported. The National Thyroid Cancer Treatment Cooperative Study Registry was established in 1986 to define clinical practice and to address the effectiveness of therapies on morbidity and mortality by prospectively enrolling a large population of patients from multiple institutions. Patients have been stratified by uniform criteria and followed prospectively from the time of initial diagnosis and treatment. This 9-year report from the registry describes outcomes in patients with high-risk, differentiated thyroid cancer, a group of patients expected to have substantial morbidity and mortality in this time period. Methods A total of 1607 patients in whom thyroid cancer was diagnosed on or after 1 January 1987 were prospectively enrolled in the registry by the 14 participating institutions. No more than 20% of cases came from any single institution or city. Data forwarded to the registry were coded, and individual identifiers, such as name and Social Security number, were kept confidentially by the principal investigator at each institution. Because the patients therapy was not altered by participation in the registry, requirements for informed consent were determined by the institutional review boards at each participating institution, and their mandates were followed. Age, sex, ethnic background, histologic diagnosis, size of primary tumor, multifocality, local invasiveness, and regional or distant metastases were documented. The histologic diagnosis was established at each institution. All variants of papillary cancer, including so-called mixed papillary and follicular carcinomas, were included in the papillary group. Analyses for papillary carcinomas that included and excluded the more aggressive tall-cell variant were performed. The Hurthle cell (oxyphilic) variant of follicular carcinoma was excluded from the follicular group. Patients were stratified on the basis of pathologic diagnosis, age, tumor size, local invasiveness, and extent of metastases at the time of first surgical intervention as determined by gross and histologic findings at surgery, whole-body radioiodine scans, chest radiographs, and other radiologic studies. This stratification system was established empirically before initiation of the registry by a group of experienced clinicians on the basis of information available in 1985. The criteria for categorization as high risk are noted in Table 1. Patients with preoperative vocal cord paresis or with postoperative hypocalcemia or vocal cord paresis that persisted 2 months or less were not designated as having these complications of surgery. The extent of initial surgery, use of postoperative radioiodine therapy, and application of external radiation therapy were analyzed for impact on outcome. With rare exceptions, all patients received thyroxine therapy. Table 1. Criteria for Stratification to High-Risk Groups Outcomes were death due to thyroid cancer or to complications of its treatment, progression (defined as a patient alive with progressive thyroid cancer or dead because of thyroid cancer or complications of its treatment at last follow-up), and disease-free survival (defined as a patient alive with no known residual thyroid cancer or free of thyroid cancer at the time of death from other causes). Statistical Analysis All data were extracted by using a computer-based integrated data management package (Med-log, Information Analysis Corporation, Incline Village, Nevada). Cox proportional-hazards models were performed to determine whether each predictor variable was associated on univariate analysis (Table 2) with survival, progression, and disease-free survival (SAS Institute, Cary, North Carolina). The hazard model was also used to identify the set of predictor variables that best explained the probabilities of overall survival, cancer-specific mortality, progression of disease, or disease-free survival (Table 3). A P value of 0.05 or less was considered statistically significant. Risk ratios obtained from the Cox proportional-hazards analyses are given with 95% CIs. Risk ratios less than 1 indicate improved outcome, and those greater than 1 indicate a worsened outcome. Table 2. Variables Associated with Mortality, Progression, and Disease-Free Survival (by Univariate Analysis) Table 3. Variables That Best Predict Overall Mortality, Cancer-Specific Mortality, Progression of Disease, or Disease-Free Survival (by Multivariate Analysis) Results Follow-up Three hundred three patients with papillary carcinoma and 82 patients with follicular carcinoma were considered to have high-risk thyroid cancer. Twenty patients (5.2%) were lost to follow-up. An additional 64 patients were not included in the survival analyses because no information on patient status was available (n = 60), no cause of death was recorded (n = 2), or patients were alive with no cancer status reported (n = 2). Demographic characteristics of the two groups were similar regardless of whether these cases were included. Patients were followed for a mean of 3.1 years after the date of surgery; 35% were men. The mean (SD) age at entry was 57 15 years. Sex and Age Compared with men, women with papillary cancer had a lower risk for overall mortality (risk ratio [RR], 0.03 [95% CI, 0.23 to 0.92]) but not cancer-specific mortality. Older age did not affect outcome in patients with papillary carcinoma or those with follicular carcinoma, but an age effect might be masked by the fact that age was a factor in defining these high-risk patients. Histologic Type Only 18 patients with papillary cancer had the tall-cell variant (P not significant by multivariate analysis). By univariate analysis, radioiodine therapy was associated with reduced disease progression (risk ratio, 0.10 [CI, 0.01 to 0.72]; P = 0.02). Thyroid Surgery The first surgical procedure on the thyroid and any surgical therapy of the thyroid that occurred within the next 4 months were classified as initial thyroid surgery. Data were not sufficient to allow analysis of the effect of modified neck dissections on complication rates. Of 300 patients with papillary cancer, 256 (85.3%) had a total or near-total thyroidectomy as initial thyroid surgery, 10 (3.3%) had bilateral subtotal thyroidectomy, 26 (8.7%) had lobectomy, 1 (0.3%) had lumpectomy, 4 (1.3%) had biopsy only, and 3 (1.0%) had nonspecified surgery. Of 80 patients with follicular cancer, 57 (71.3%) had total or near-total thyroidectomy as initial thyroid surgery, 2 (2.5%) had bilateral subtotal thyroidectomy, 13 (16.3%) had lobectomy, 4 (5.0%) had lumpectomy, and 4 (5.0%) had biopsy only. The charts of all patients with reported surgical complications were reviewed. The complication rate of initial surgery varied among centers. The overall rate of some type of complication was 14.4% (52 of 360 patients). Specific data on complications were available for 286 of 303 patients with papillary cancer and 74 of 82 patients with follicular thyroid cancer. Hypoparathyroidism alone occurred in 19 of 286 (6.6%) patients with papillary cancer and 3 of 74 (4.0%) patients with follicular cancer. Vocal cord palsy alone was noted in 17 of 286 (5.9%) patients with papillary cancer and 6 of 74 (8.0%) patients with follicular cancer. Combined hypoparathyroidism and vocal cord palsy occurred in 4 of 286 (1.4%) patients with papillary cancer and no patients with follicular cancer. Data were not sufficient to allow analysis of any effect of modified neck dissections on complication rates. Overall mortality from papillary cancer improved with total or near-total thyroidectomy compared with other surgical procedures (RR, 0.41 [CI, 0.20 to 0.85]) (Table 2). Progression of disease and disease-free survival were not improved by more extensive surgery, and surgery did not affect mortality, progression, or disease-free survival in patients with follicular cancer by univariate (Table 2) or multivariate (Table 3) analyses. Radioiodine Therapy Postoperative radioiodine therapy with iodine-131 was administered to 258 of 302 (85.4%) patients with papillary cancer; the init


Medicine and Science in Sports and Exercise | 1996

Bone mineral density in elite 7- to 9-yr-old female gymnasts and swimmers.

Cynthia Cassell; Michael Benedict; Bonny Specker

It is has been suggested that physical activity may increase bone mineral density (BMD) in children, thereby preventing development of osteoporosis later in life. We studied 14 gymnasts, 14 swimmers, and 17 controls to investigate whether participation in different types of sports among girls 7-9 yr of age is associated with higher total body BMD. Gymnasts were lighter than both swimmers and controls (P = 0.001), and a larger percent of gymnasts compared with swimmers and controls were below the 25th percentile for height and weight. Fat mass, percent body fat, and lean mass were less in gymnasts compared with swimmers and controls (all P < or = 0.05). The relationship between total body BMD and body weight differed among the three groups (interaction term of weight and sport, P < 0.001); the increase in BMD per unit increase in body weight was more among gymnasts than among swimmers and controls. These results indicate that high impact bone loading activities may lead to increased bone density among young girls.


The Journal of Clinical Endocrinology and Metabolism | 2016

Consensus Statement: Global Consensus Recommendations on Prevention and Management of Nutritional Rickets

Craig Munns; Nick Shaw; Mairead Kiely; Bonny Specker; Tom D. Thacher; Keiichi Ozono; Toshimi Michigami; Dov Tiosano; M. Zulf Mughal; Outi Mäkitie; Lorna Ramos-Abad; Leanne M. Ward; Linda A. DiMeglio; Navoda Atapattu; Hamilton Cassinelli; Christian Braegger; John M. Pettifor; Anju Seth; Hafsatu Wasagu Idris; Vijayalakshmi Bhatia; Junfen Fu; Gail R. Goldberg; Lars Sävendahl; Rajesh Khadgawat; Pawel Pludowski; Jane Maddock; Elina Hyppönen; Abiola Oduwole; Emma Frew; Magda Aguiar

BACKGROUND Vitamin D and calcium deficiencies are common worldwide, causing nutritional rickets and osteomalacia, which have a major impact on health, growth, and development of infants, children, and adolescents; the consequences can be lethal or can last into adulthood. The goals of this evidence-based consensus document are to provide health care professionals with guidance for prevention, diagnosis, and management of nutritional rickets and to provide policy makers with a framework to work toward its eradication. EVIDENCE A systematic literature search examining the definition, diagnosis, treatment, and prevention of nutritional rickets in children was conducted. Evidence-based recommendations were developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system that describe the strength of the recommendation and the quality of supporting evidence. PROCESS Thirty-three nominated experts in pediatric endocrinology, pediatrics, nutrition, epidemiology, public health, and health economics evaluated the evidence on specific questions within five working groups. The consensus group, representing 11 international scientific organizations, participated in a multiday conference in May 2014 to reach a global evidence-based consensus. RESULTS This consensus document defines nutritional rickets and its diagnostic criteria and describes the clinical management of rickets and osteomalacia. Risk factors, particularly in mothers and infants, are ranked, and specific prevention recommendations including food fortification and supplementation are offered for both the clinical and public health contexts. CONCLUSION Rickets, osteomalacia, and vitamin D and calcium deficiencies are preventable global public health problems in infants, children, and adolescents. Implementation of international rickets prevention programs, including supplementation and food fortification, is urgently required.


The Journal of Pediatrics | 1992

Prospective study of vitamin D supplementation and rickets in China

Bonny Specker; Mona L. Ho; Alan E. Oestreich; Tai-an Yin; Qing-mei Shui; Xue-cun Chen; Reginald C. Tsang

To determine whether amounts of vitamin D lower than recommended doses are effective in preventing rickets, 256 term infants from two northern and two southern cities in China were studied in a randomized trial of vitamin D supplementation (100, 200, or 400 IU/day) during the first 6 months of life. Cord blood and 6-month blood samples were collected and radiographs were obtained at 3 to 5 days and at 6 months of age. Cord serum 25-hydroxyvitamin D concentrations were lower in the north than in the south (5 vs 14 ng/ml (12.5 vs 35.0 nmol/L); p less than 0.01). Wrist ossification centers were less likely to be present at birth in the northern children than in the southern children (p = 0.009) and were more likely to be present in infants born in the fall who had higher cord serum concentrations of 25-hydroxyvitamin D (p = 0.04). Serum 25-hydroxyvitamin D concentrations were lower in northern children 6 months of age than in southern children (p = 0.005) and were higher with an increasing supplemental dosage of vitamin D (p less than 0.001), particularly in infants in the north. None of the infants had rickets at 6 months of age. Because of the low serum 25-hydroxyvitamin D concentrations, especially among infants in the north, it may be prudent to supplement the diet with vitamin D at a dose of 400 IU/day.

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Teresa Binkley

South Dakota State University

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Tianna Beare

South Dakota State University

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Lee Weidauer

South Dakota State University

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Howard Wey

South Dakota State University

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Matthew D. Vukovich

South Dakota State University

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Mona Ho

Cincinnati Children's Hospital Medical Center

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Mona L. Ho

University of Cincinnati

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Heidi J. Kalkwarf

Cincinnati Children's Hospital Medical Center

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Maggie Minett

South Dakota State University

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James E. Heubi

Cincinnati Children's Hospital Medical Center

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