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Background: Breast cancer risk increases during pregnancy and remains elevated for a number of years thereafter. Cancer-associated proteins that are secreted into breast milk may provide a means to detect cancer in the lactating breast or to assess future breast cancer risk. Objective: To determine whether proteins linked to breast cancer would be differentially expressed in matched (both breasts from each participant) human milk samples collected from women with unilateral breast cancer. Methods: Five cancer-associated proteins (basic fibroblast growth factor [bFGF], YKL-40, neutrophil gelatinase-associated lipocalin, and transforming growth factor β1 and β2) were analyzed in milk provided by 5 lactating women, 4 of whom were known to have cancer in 1 breast (and the opposite breast clinically disease free) at the time of milk collection and 1 who developed breast cancer 2 years after milk collection. Results: Expression was significantly higher for TGFβ2 ( P = .03) and bFGF ( P =.03) in the breasts with cancer. Conclusion: These proteins may play a role in assessing a woman’s risk of pregnancy-associated breast cancer. Because of variable protein concentration among patients and the limited sample size, the results are considered preliminary.

A method has been developed that enables resonance Raman spectra of photolabile species in solution to be recorded under conditions where the level of photoalteration is controlled: a low level enables reactant spectra to be recorded, whereas a high level enables the spectra of short-lived transient species to be recorded in real time using continuous-wave (CW) lasers and standard Raman detection equipment. The design includes a sealed flow system, enabling air-sensitive species to be studied under an inert atmosphere. A simple theoretical model has been developed to aid the interpretation of experimental results, and its applicability is demonstrated. Controlled photoalteration and its theory are demonstrated with 413.1-nm excitation of carbonmonoxymyoglobin (MbCO), which generates deoxymyoglobin (deoxy-Mb) on photolysis, and for which the spectra of both species are well established. The methods have also been applied to two air-sensitive, photolabile transition metal carbonyls using 514.5-nm wavelength excitation: for Cp2Mo2(CO)6 (Cp = η5–C5H5), increasing levels of photoalteration result only in a decrease in the parent band intensities, relative to the solvent bands; for Cp2Fe2(CO)4, increasing levels of photoalteration result in the appearance of additional bands that are assigned to the transient species CpFe(μ–CO)3FeCp, formed following the loss of a CO ligand.

An ultrafast laser apparatus has been developed that allows time-resolved UV-visible and infrared spectroscopy to be performed with a time resolution of 200 fs. The instrument design allows UV-vis and IR data to be collected either as spectra or as kinetic profiles. Solution flow and cell translation sampling systems have been developed that allow the handling of chemical and biochemical systems, including highly air-sensitive materials and volumes as small as 50 μL. The apparatus performance has been evaluated with the use of trans-stilbene in hexane (UV-vis) and silicon (IR) test samples, and the techniques have been applied in combination to study both native carbonmonoxymyoglobin and the novel H64L mutant.

This paper evaluates age, period, and cohort effects on marital fertility during onset of the Utah fertility transition (1880–1909). Computerized genealogies are used to derive age–period–cohort fertility rates for 49,842 once-married couples. Age, period and cohort effects on marital fertility are then estimated using Johnson's (1985) relational model. Declining marital fertility in Utah is shown to be explained by both lower fertility levels across periods and increasing age-specific limitation across cohorts. Direct cohort effects on fertility are insignificant. These results are consistent with prior research, and the view that fertility levels were adaptive (in part through birth spacing across ages) to immediate contexts of childbearing while age-specific fertility truncation increased across cohorts (in part through the more general diffusion of contraceptive innovations).

Fertility in the United Statesnew patterns, new theories , Fertility in the United Statesnew patterns, new theories , کتابخانه مرکزی دانشگاه علوم پزشکی تهران

This study focuses on the relationship between fertility and migration in families settling the Utah Territory. Genealogical data are used to identify the timing of migration (i.e., after, during, or before childbearing) and country of originfor migrants; and to analyze both fer tility levels for different types of migrants and the changes in fertility behavior associated with these levels. The highest fertility levels are among adults who migrated during their reproductive ages. Those who migrated young, before childbearing began, have lower fertility and are similar to natives of the frontier. Adult immigrants and emigrants of the Utah Territory use multiple strategies offamily formation.