Medicine and Health Sciences Commons^™

Prepubertal Organochlorine Pesticide Concentrations And Age Of Pubertal Onset Among Russian Boys, Thuy Lam, Paige Williams, Mary Lee, Susan Korrick, Linda Birnbaum, Jane Burns, Oleg Sergeyev, Boris Revich, Larisa Altshul, Donald Patterson, Wayman Turner, Russ Hauser

Mary M. Lee

BACKGROUND: In animal studies, organochlorine pesticide (OCP) exposure alters pubertal development; however, epidemiological data are limited and inconsistent. OBJECTIVE: To evaluate the associations of serum OCP concentrations [hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE)] with male pubertal onset. METHODS: In Chapaevsk, Russia, a town environmentally contaminated with OCPs, 350 8-9 year old boys with measured OCPs were enrolled during 2003-2005 and were followed annually for eight years. We evaluated three measures of pubertal onset: testicular volume (TV) > 3 mL in either testis, or stage 2 or greater for genitalia (G2+), or pubic hair (P2+). We used multivariable interval-censored models to …

Association Between Chlorinated Pesticides In The Serum Of Prepubertal Russian Boys And Longitudinal Biomarkers Of Metabolic Function, Jane Burns, Paige Williams, Susan Korrick, Russ Hauser, Oleg Sergeyev, Boris Revich, Thuy Lam, Mary Lee

Mary M. Lee

Organochlorine pesticides (OCPs) have been linked to adult metabolic disorders; however, few studies have examined these associations in childhood. We prospectively evaluated the associations of baseline serum OCPs (hexachlorobenzene, beta-hexachlorocyclohexane, and p,p'-dichlorodiphenyldichloroethylene) in Russian boys with subsequent repeated measurements of serum glucose, insulin, lipids, leptin, and calculated homeostatic model assessment of insulin resistance (IR). During 2003-2005, we enrolled 499 boys aged 8-9 years in a prospective cohort; 318 had baseline serum OCPs and serum biomarkers measured at ages 10-13 years. Multivariable generalized estimating equation and mediation regression models were used to examine associations and direct and indirect (via body mass …

Evaluation Of Short And Tall Stature In Children, Benjamin Nwosu, Mary Lee

Mary M. Lee

Children and adolescents whose heights and growth velocities deviate from the normal percentiles on standard growth charts present a special challenge to physicians. Height that is less than the 3rd percentile or greater than the 97th percentile is deemed short or tall stature, respectively. A growth velocity outside the 25th to 75th percentile range may be considered abnormal. Serial height measurements over time documented on a growth chart are key in identifying abnormal growth. Short or tall stature is usually caused by variants of a normal growth pattern, although some patients may have serious underlying pathologies. A comprehensive history and …

Pubertal And Adult Leydig Cell Function In Mullerian Inhibiting Substance-Deficient Mice, Xiufeng Wu, Ramamani Arumugam, Stephen Baker, Mary Lee

Mary M. Lee

Mullerian inhibiting substance (MIS) causes Mullerian duct regression during sexual differentiation and regulates postnatal Leydig cell development. MIS knockout (MIS-KO) mice with targeted deletions of MIS develop Leydig cell hyperplasia, but their circulating androgen concentrations are reportedly unaltered. We compared reproductive hormone profiles, androgen biosynthesis, and the expression of key steroidogenic and metabolic enzymes in MIS-KO and wild-type (WT) mice at puberty (36 d) and sexual maturity (60 d). In pubertal animals, basal testosterone and LH concentrations in plasma were lower in MIS-KO than WT mice, whereas human chorionic gonadotropin-stimulated testosterone concentrations were similar. In adults, basal LH, and both …

Social Support To Empower Parents (Step): An Intervention For Parents Of Young Children Newly Diagnosed With Type 1 Diabetes, Susan Sullivan-Bolyai, Carol Bova, Katherine Leung, Allison Trudeau, Mary Lee, Philip Gruppuso

Mary M. Lee

PURPOSE: The purpose of this study was to test the efficacy of a social support intervention with parents of children <13 years old newly diagnosed with type 1 diabetes mellitus>(T1DM).

METHODS: For this randomized, controlled clinical trial, 10 parent mentors of children diagnosed with T1DM >or=1 year and 60 parent participants were recruited from 2 pediatric diabetes centers. Mentors were trained to provide social support (home visits and phone calls) for 12 months to families in the experimental arm (32 mothers). Control group parents (28 mothers) received the phone number of an experienced parent (not trained to give social support) to call as needed.

FINDINGS: Mothers in the experimental …

A Single Base Pair Mutation Encoding A Premature Stop Codon In The Mis Type Ii Receptor Is Responsible For Canine Persistent Mullerian Duct Syndrome, Wenfang Wu, Shengqin Wan, Pujar Shashikant, Mark Haskins, Donald Schlafer, Mary Lee, Vicki Meyers-Wallen

Mary M. Lee

Mullerian inhibiting substance (MIS), a secreted glycoprotein in the transforming growth factor-beta family of growth factors, mediates regression of the Mullerian ducts during embryonic sex differentiation in males. In persistent Mullerian duct syndrome (PMDS), rather than undergoing involution, the Mullerian ducts persist in males, giving rise to the uterus, fallopian tubes, and upper vagina. Genetic defects in MIS or its receptor (MISRII) have been identified in patients with PMDS. The phenotype in the canine model of PMDS derived from the miniature schnauzer breed is strikingly similar to that of human patients. In this model, PMDS is inherited as a sex-limited …

The Increased Incidence Of Congenital Hypothyroidism: Fact Or Fancy?, Marvin Mitchell, Ho-Wen Hsu, Inderneel Sahai, Stuart Brink, Laurie Cohen, Rosalind Brown, Roger Eaton, Mary Lee, Lynne Levitsky, Edward Reiter, Abdollah Sadeghi-Nejad, Leslie Soyka, Joseph Wolfsdorf

Mary M. Lee

OBJECTIVE: The incidence of congenital hypothyroidism (CH) detected by newborn screening in the US has increased significantly since the early 1990s. We defined the characteristics associated with the increased incidence. PATIENTS: A cohort of children with CH born during an earlier period of low incidence (1991-94) was compared with a cohort born during a later period when the incidence of CH had doubled (2001-04). MEASUREMENTS: Screening was performed with T4 as the primary marker and thyroid stimulating hormone (TSH) on selected specimens. Follow-up on hypothyroid children determined whether they had permanent or transient hypothyroidism. Cases were classified based on laboratory …

Evidence Of Insulin-Like Growth Factor Binding Protein-3 Proteolysis During Growth Hormone Stimulation Testing, Benjamin Nwosu, Leslie Soyka, Amanda Angelescu, Mary Lee

Mary M. Lee

OBJECTIVES: The ternary complex is composed of insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3 and acid labile subunit (ALS). Growth hormone (GH) promotes IGFBP-3 proteolysis to release free IGF-I, ALS, and IGFBP-3 fragments. Our aim was to determine whether elevated GH levels during GH stimulation testing would trigger IGFBP-3 proteolysis. DESIGN: This prospective study of 10 short prepubertal children (height standard deviation score -2.37 +/- 0.31) used arginine and GH releasing hormone stimulation to study dynamic changes in the ternary complex moieties. IGFBP-3 was measured in two assays: a radioimmunoassay (RIA) that detects both cleaved and intact IGFBP-3; and …

Dioxin And Polychlorinated Biphenyl Concentrations In Mother's Serum And The Timing Of Pubertal Onset In Sons, Olivier Humblet, Paige Williams, Susan Korrick, Oleg Sergeyev, Claude Emond, Linda Birnbaum, Jane Burns, Larisa Altshul, Donald Patterson, Wayman Turner, Mary Lee, Boris Revich, Russ Hauser

Mary M. Lee

BACKGROUND: Animal studies have demonstrated that timing of pubertal onset can be altered by prenatal exposure to dioxins or polychlorinated biphenyls (PCBs), but studies of human populations have been quite limited.

METHODS: We assessed the association between maternal serum concentrations of dioxins and PCBs and the sons' age of pubertal onset in a prospective cohort of 489 mother-son pairs from Chapaevsk, Russia, a town contaminated with these chemicals during past industrial activity. The boys were recruited at ages 8 to 9 years, and 4 years of annual follow-up data were included in the analysis. Serum samples were collected at enrollment …

Farm Residence And Reproductive Health Among Boys In Rural South Africa, Rene English, Melissa Perry, Mary Lee, Elaine Hoffman, Steven Delport, Mohamed Dalvie

Mary M. Lee

BACKGROUND: Few studies have investigated reproductive health effects of contemporary agricultural pesticides in boys. OBJECTIVES: To determine the association between pesticide exposure and reproductive health of boys. METHODS: We conducted a cross-sectional study in rural South Africa of boys living on and off farms. The study included a questionnaire (demographics, general and reproductive health, phyto-estrogen intake, residential history, pesticide exposures, exposures during pregnancy); and a physical examination that included sexual maturity development ratings; testicular volume; height, weight, body mass index; and sex hormone concentrations. RESULTS: Among the 269 boys recruited into the study, 177 (65.8%) were categorized as farm (high …