Pregnancy Inhibits Mammary Carcinogenesis by Persistently Altering the Hypothalamic-Pituitary Axis.

Early full-term pregnancy is known to reduce the lifetime risk of breast cancer. Although the phenomenon of parity-induced protection is well-established, the physiological mechanisms involved in this protection are not clear. Earlier reports have shown that pregnancy results in alterations of hormone levels.

Growth dynamics of juvenile loggerhead sea turtles undergoing an ontogenetic habitat shift.

Ontogenetic niche theory predicts that individuals may undergo one or more changes in habitat or diet throughout their lifetime to maintain optimal growth rates, or to optimize trade-offs between mortality risk and growth. We combine skeletochronological and stable nitrogen isotope (δN) analyses of sea turtle humeri (n = 61) to characterize the growth dynamics of juvenile loggerhead sea turtles (Caretta caretta) during an oceanic-to-neritic ontogenetic shift. The primary objective of this study was to determine how ontogenetic niche theory extends to sea turtles, and to individuals with different patterns of resource use (discrete shifters, n = 23; facultative shifters n = 14; non-shifters, n = 24).

Yield of Urinalysis Screening in Pediatric Cancer Survivors.

Background: The Children's Oncology Group (COG) publishes consensus guidelines with screening recommendations for early identification of treatment-related morbidities among childhood cancer survivors. We sought to estimate the yield of recommended yearly urinalysis screening for genitourinary complications as per Version 3.0 of the COG Long-Term Follow-Up Guidelines and identify possible risk factors for abnormal screening in a survivor population.

Effects of demineralization on the stable isotope analysis of bone samples.

Rationale: The sampling of sequential, annually formed bone growth layers for stable carbon (δ(13)C values) and nitrogen (δ(15)N values) isotope analysis (SIA) can provide a time series of foraging ecology data. To date, no standard protocol exists for the pre-SIA treatment of cortical samples taken from fresh, modern, bones.

Methods: Based on the SIA of historical bone, it is assumed that fresh bone samples must be pre-treated with acid prior to SIA.