Effects of parity on pregnancy hormonal profiles across ethnic groups with a diverse incidence of breast cancer.

Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk.     

Thermodynamics of norbornene,of its polymerization process and of polynorbornene from 0 to 400 K at standard pressure

Thermodynamic properties of norbornene

1 System: name: bicyclo[2.2.1]hept-2-ene.

and polynorbornene, viz. isobaric heat capacity of the monomer and polymer between 10 and 330–400 K, parameters of physical transitions of the monomer and polymer, and energy of combustion for the polymer were studied by means of precise adiabatic and isothermal calorimetry. From the experimental data, the thermodynamic functions H°(T)–H°(0), S°(T) and G°(T)–H°(0) in the range of 0 to 330–400 K as well as enthalpies of combustion and thermochemical quantities of formation ΔH, and ΔS for polynorbornene were calculated. The results were used to calculate enthalpies, entropies and Gibbs functions of bulk polymerization for norbornene between 0 and 330 K and to evaluate the ceiling temperature of polymerization.     

ASO Visual Abstract: Association of Obesity with Worse Operative and Oncologic Outcomes Among Patients Undergoing Gastric Cancer Resection

Annals of Surgical Oncology -     

Regulatory cytokine production stimulated by DNA vaccination against an altered form of glutamic acid decarboxylase 65 in nonobese diabetic mice

Nonobese diabetic (NOD) mice develop a T-cell dependent autoimmune form of diabetes, in which glutamic acid decarboxylase 65 (GAD65) is an important islet target antigen. Intramuscular DNA vaccination with a plasmid encoding native GAD65 (a cytosolic antigen) did not significantly alter the incidence of diabetes, but vaccination against an altered form of GAD65 with a signal peptide (spGAD), which is secreted in vitro, was protective. The preventive effect was further enhanced by repeated injections of the spGAD plasmid. Following DNA injection into muscle GAD65 was expressed for several months, and this was not accompanied by an inflammatory response. Immunization against GAD65 was not associated with substantial alterations in cytokine production by splenic lymphocytes stimulated with immunogenic GAD65 peptides. In contrast, spGAD induced increased secretion of both interleukin 10 and interferon gamma and a striking decrease in the interferon gamma/interleukin 10 ratio in culture supernatants. Similarly, spGAD-immunized mice had higher serum interleukin 10 levels and lower serum interferon gamma levels than other groups, suggesting a systemic effect. In nondiabetic mice there was increased basal production of transforming growth factor beta(1), which was enhanced by antigenic stimulation. These alterations in regulatory cytokine production were apparent both early and late after the treatment was initiated. These findings suggest that DNA vaccination against spGAD protects NOD mice by increasing regulatory cytokine production.