Research fetuses

Holmberg, B., Nelson, A. and Wallgren, E. 1960 The transfer of Sr-90 from mother to fetus in mice. Radiation Research 12 167-172. 

Certain subgroups of the population may be more susceptible to the toxic effects of lead exposure. These include crawling and house-bound children (<6 years old), pregnant women (and the fetus), the elderly, smokers, alcoholics, and people with genetic diseases affecting heme synthesis, nutritional deficiencies, and neurological or kidney dysfunction. This is not an exhaustive list and reflects only current data available, further research may identify additional susceptible subgroups. 

Further research on the relationship between paternal lead exposure and fetal/infant development should be conducted. Additional information on relationships between nutritional deficits and vulnerability of the fetus and child to lead would be valuable. 

There are two general avenues for stem cell research pluripotent and multipotent stem cells. Pluripotent stem cells are obtained by two methods. One method is to harvest the clusters of cells from the blastocysts of human embryos. Another method is the isolation of pluripotent cells from fetuses in terminated pregnancies. Multipotent stem cells are derived from umbihcal cords or adult... 

A burning issue is the ethics of obtaining pluripotent stem cells from embryos and fetuses. The US government has acted on this issue and declared that federal funds for stem cell research have to meet certain criteria. It requires that funding will only be provided to research with stem cells obtained before August 9, 2001, as a cut-off date to limit research to preexisting stem cells. Refer to Section 11.7 for an ethical debate on stem cells. 

First, I will discuss the development of responses to odors and follow this by the development of odor production. Mammals spontaneously respond to odors in utero and can also be conditioned to chemical stimuli before birth. Much research has focused on the chemical ecology of the fetus. Experience plays an... 

The mechanisms of action of the effects of alcohol on the nervous system remain unclear. For some time, researchers thought that the depressant effects of alcohol, like other anesthetic agents, were caused by dissolving into the cell lipid membranes and disrupting the function of various proteins. More recently, researchers have focused on specific receptors such as glutamate (excitatory) and GABA (inhibitory). Despite intensive research, the mechanism of effect of alcohol on the fetus is unknown. 

The prenatal developmental toxicity study design includes sacrifice of the rodent or rabbit dam one day prior to expected delivery, in order to ensure that malformed fetuses are not lost to maternal cannibalism. .. Nevertheless, even the prenatal developmental toxicity study does not allow the researcher to distinguish the source or cause of prenatal mortality. Intrauterine deaths may be the result of malformations that are incompatible with continuing viability... The contribution of malformed fetuses to overall effect on litter viability can be appropriately analysed by combining the litter incidence of conceptuses that are malformed, resorbed (early and late), and dead (full term but nonviable at caesarean section) and performing appropriate statistical analyses of group values (13). 

Cellular therapy is the replacement of lost or dysfunctional tissues with new ones. Various cell types have been evaluated and considered for therapy. In the CNS, fetal neuronal tissue has been particularly evaluated for its merit in treating neurological diseases and injuries [1]. While numerous experimental and clinical transplantation studies showed that fetal neuronal transplants improve functional deficits in models of CNS diseases [2-5], others reported less positive outcomes [6, 7]. In addition, the rate of survival of fetal neuronal cells transplanted into the adult brain is relatively low, requiring large quantities of tissue, generally from several fetuses, for therapy. Researchers are looking at other opportunities for cellular therapy, particularly in the CNS. 

Initiatives by medical researchers, by DES Action, and by the Public Citizen s Health Research Group secured funding in the USA for medical research on the prevalence of cancer and other effects in the young women who had been exposed in utero, and eventually also the men. The US National Institute for Environmental Health Sciences (NIEHS) has been one of the centers for toxicological studies of the effects of diethylstilbestrol. A substantial amount of research on the effects of diethylstilbestrol— animal experiments as well as epidemiological studies— has produced a valuable body of knowledge about how hormones affect the development of the fetus and prime the individual for disease later in life. 

Many organ systems in the human body can be affected by chronic exposure to arsenic (Agency for Toxic Substances and Disease Registry (ATSDR), 2007 World Health Organization (WHO), 2001 National Research Council (NRC), 1999, 2001). These include the skin, developing fetus, liver and the cardiovascular, pulmonary, nervous, and endocrine systems. These effects are dose-related and primarily arise from oral exposure to arsenic, although inhalation of arsenic may also result in adverse health effects. The chronic effects from dermal exposure to arsenic are not known. 

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