Human developmental exposure to endocrine active compounds

Pre-birth acquisition of personhood: Incremental accrual of attributes as the framework for individualization by serial and concurrently acting developmental factors

Discrete events and processes influence development of individual humans. Attribution of personhood to any individual human being cannot be disconnected from the underlying biological events and processes of early human development. Nonetheless, the philosophical, sociological and legal components that are integral to the meaning of the term as commonly used cannot be deduced from biology alone. The challenge for biomedical scientists to inform discussion in this arena then rests on profiling the key biological events and processes that must be assessed when considering how one might objectively reason about the task of superimposing the concept of personhood onto the developing biological entity of a potential human being. Endogenous genetic and epigenetic events and exogenous developmental milieu processes diversify developmental trajectories of potential individual humans prior to livebirth. First, fertilization and epigenetic resetting of each individual's organismic clock to time zero (t = 0) at the gastrulation/primitive streak stage (day 15 of embryogenesis), are two discrete unseen biological events that impact a potential individual human's attributes. Second, those two discrete unseen biological events are immersed in the continuous developmental process spanning pre-fertilization and gestation, further driving individualization of diverse attributes of each future human before the third discrete and blatant biological event of parturition and livebirth. Exposures of the gravida to multiple diverse exogenous exposures means that morphogenesis and physiogenesis of every embryo/fetus has individualized attributes for its future human lifespan. Our proposed framework based on the biological discrete events and processes spanning pre-fertilization and prenatal development, implies that personhood should be incrementally attributed, and societal protections should be graduated and applied progressively across the pre-birth timespan.

Hexachlorocyclohexane (HCH) in human blood in the south of the Russian Far East

The content of organochlorine pesticides in blood of residents of the Russian Far East is assessed. Among hexachlorocyclohexane isomers, only β-HCH has been found. This fact indicates that contamination of the environment and human organisms by this pesticide began long ago. Its concentration varies from 2060 to 22,230 ng/g lipid. The probable sources of the toxicant found in human organisms are discussed.

PASSIVE CONTROL OF HUMAN BODY COMPLEX SINGULAR SYSTEMS

Due to the complexity of interaction among constituents inside the whole system, it is difficult to establish accurate mathematics models to describe and analyze the complex systems exactly. There are few attempts concerning on the moving process of endocrine disruptor in human bodies, which have been the polluted material worldwide related to the reproduction, existence and development of human being. Focusing on such two challenging issues, a multi-compartment model of endocrine disruptor Benzene moving in the human body complex system is established in this paper. Furthermore, passivity of this model is described systematically. A feedback controller for this descriptor biological complex system is used under the station of strict passivity, and an example of the controller is given for a particular instantiation of the model.

From mother to child: investigation of prenatal and postnatal exposure to persistent bioaccumulating toxicants using breast milk and placenta biomonitoring

The exposure levels of placenta and paired breast milk samples to selected organochlorine compounds and pesticides from Danish and Finnish samples have been investigated. p,p'-DDE is the dominant pollutant, beta-HCH, hexachlorobenzene, endosulfan-I, dieldrin, oxychlordane, cis-heptachlor epoxide and p,p'-DDT being the other major constituents. Their concentrations are linearly correlated between milk and placenta in similar patterns for Danish and Finnish samples. Milk samples have higher levels of these pollutants than placenta on lipid base. However, the apparently not correlated compounds, such as alpha-HCH, pentachlorobenzene, pentachloroanisole and methoxychlor, are generally accumulated more in placenta, which may suggest a tissue specific metabolic activity. Thus, depending on the compound of interest, biomonitoring may be done in placenta only or in both matrices.

The stimulation of cell proliferation by quercetin is mediated by the estrogen receptor

Quercetin causes biphasic modulation of the proliferation of specific colon and mammary cancer cells. In this study, the possible involvement of the estrogen receptor (ER) in the stimulation of cell proliferation by quercetin was investigated. For this purpose, the effect of quercetin on cell proliferation was tested in ER-positive MCF-7 and T47D cells, and in ER-negative HCC-38 and MDA-MB231 cells. Quercetin stimulated proliferation of ER-positive cells only, suggesting this effect to be ER-dependent. In support of these results, quercetin induced ER-ERE-mediated gene expression in a reporter gene assay using U2-OS cells transfected with either ERalpha or ERbeta, with 10(5)-10(6) times lower affinity than 17beta-estradiol (E2) and 10(2)-10(3 )times lower affinity than genistein. Quercetin activated the ERbeta to a 4.5-fold higher level than E2, whereas the maximum induction level of ERalpha by quercetin was only 1.7 fold that of E2. These results point at the relatively high capacity of quercetin to stimulate supposed 'beneficial' ERbeta responses as compared to the stimulation of ERalpha, the receptor possibly involved in adverse cell proliferative effects. Altogether, the results of this study reveal that physiologically relevant concentrations of quercetin can exert phytoestrogen-like activity similar to that observed for the isoflavonoid genistein.