Traits,factors, and genes

Abstract

Relatively little is known about the motivational antecedents to the use of assisted reproductive technology (ART). In this paper we measure the fertility motivations of infertile couples who are considering the use of ART, using an established instrument, the Childbearing Questionnaire (CBQ). Our sample consists of 214 men and 216 women who were interviewed at home after an initial screening for ART but before making a final decision. We conducted two sets of analyses with the obtained data. In one set, we compared the scores on scales and subscales of the CBQ for the males and females in our sample with the scores for males and females from a comparable normative sample. For these analyses we first examined sample and gender differences with a four‐group analysis of variance. We then conducted a series of linear models that included background characteristics as covariates and interactions between sample, gender, and age and between those three variables and the background characteristics. The results showed the expected higher positive and lower negative motivations in the ART sample and a significant effect on positive motivations of the interaction between sample and age. In the second set of analyses, we developed several new subscales relevant to facets of the desire for a child that appear to be important in ART decision‐making. These facets include the desire to be genetically related to the child and the desire to experience pregnancy and childbirth. A third facet, the desire for parenthood, is already well covered by the existing subscales. The results showed the new subscales to have satisfactory reliability and validity. The results also showed that the original and new subscales predicted the three facets of the desire for a child in a multivariate context We conclude with a general discussion of the way our findings relate both to ART decision‐making and to further research on the motivations that drive it.     

Mutagenesis and cardiovascular diseases Molecular mechanisms, risk factors, and protective factors

Although no generalization can be made, it is of interest that cancer, cardiovascular diseases, and other chronic conditions often share common risk factors and common protective factors as well as common pathogenetic determinants, such as DNA damage, oxidative stress, and chronic inflammation. Atherosclerosis is the most important cause of vascular forms representing the major cause of death in the population of many geographical areas. A great deal of studies support the "response-to-injury" theory. A variety of experimental and epidemiological findings are also in favor of the somatic mutation theory, which maintains that the earliest event in the atherogenic process is represented by mutations in arterial smooth muscle cells, akin to formation of a benign tumor. These two theories can be harmonized, also taking into account the highly diversified nature of atherosclerotic lesions. Molecular epidemiology studies performed in our laboratory and other laboratories have shown that DNA adducts are systematically present in arterial smooth muscle cells, and their levels are correlated with atherogenic risk factors known from traditional epidemiology. Oxidative DNA damage was also consistently detected in these cells. The role of glutathione S-transferase polymorphisms on the frequency of the above molecular alterations and of arterial diseases is rather controversial. Prevention of both cancer and atherosclerosis is based on avoidance of exposure to risk factors and on fortification of the host defense mechanisms by means of dietary principles and chemopreventive drugs.     

Growth factors, oncogenes, and multistage carcinogenesis

This paper presents evidence that the full repertoire of cellular genes involved in the carcinogenic process is several times larger than that of the known list of proto-oncogenes. Furthermore, this repertoire includes genes whose normal function is related to growth stimulation, as well as genes whose normal function is to inhibit growth or induce terminal differentiation. Multistage carcinogenesis probably results from a complex series of changes in both categories of genes. Despite this complexity, carcinogenesis can be conceived in terms of disturbances in biochemical functions that normally control the expression or function of growth factors, receptors, and pathways of signal transduction. Several protein kinases play a central role in the process of signal transduction. Our laboratory has recently isolated cDNA clones for the enzyme protein kinase C (PKC). These clones should be useful for clarifying the role of PKC in growth control and tumor promotion. Finally, the existence of genes whose normal function is to inhibit cell growth provides a rationale for new strategies of cancer prevention and treatment.     

Growth factors, receptors and cancer

It now appears that the molecular events associated with the mitogenic action of growth factors are also the events perturbed in neoplastic lesions. This review outlines the relevance of our recent progress in the biochemistry of growth factors and their receptors to the induction and maintenance of the neoplastic state.     

Extrapolation, uncertainty factors, and the precautionary principle

This essay examines the relationship between the precautionary principle and uncertainty factors used by toxicologists to estimate acceptable exposure levels for toxic chemicals from animal experiments. It shows that the adoption of uncertainty factors in the United States in the 1950s can be understood by reference to the precautionary principle, but not by cost-benefit analysis because of a lack of relevant quantitative data at that time. In addition, it argues that uncertainty factors continue to be relevant to efforts to implement the precautionary principle and that the precautionary principle should not be restricted to cases involving unquantifiable hazards.     

Cytokines, growth factors, and plastic surgery.

Numerous inflammatory cytokines and growth factors have been identified and are known to be essential for normal wound healing and host defense, and many have been implicated in disease states treated by plastic surgeons. Cytokines and growth factors are members of a large functional group of polypeptide regulatory molecules secreted by different cell lines. These peptides exert their influence through autocrine and paracrine fashions within sites of injury and repair. Although cytokines and growth factors are crucial in initiating, sustaining, and regulating the postinjury response, these same molecules have been implicated in impaired wound healing, abnormal scarring, and chronic cutaneous diseases. Therapeutic manipulation of inflammatory mediators in normal and impaired wounds has been performed, with mixed clinical results, but evolving strategies such as gene therapy, as well as further characterization of the cellular-mechanism cytokines and growth-factor triggers, will further add to our therapeutic options. This article discusses the current understanding of important cytokines and growth factors involved in the normal injury response and then addresses pathological states associated with an inappropriate expression of these mediators. Finally, a summary of various cytokine and growth factor-directed strategies being used in impaired wound healing states is presented.     

mRNP proteins,initiation factors and phosphorylation

Information has been collected to stimulate interest regarding the nature and the possible role of mRNP protein phosphorylation in a cytoplasmic control mechanism for protein synthesis. It does not imply a direct relationship between mRNP protein and initiation factors. These proteins have some properties in common (e.g. molecular weight, phosphorylation, protein kinase, mRNA binding activity). We emphasize that some free mRNP may be translatable after modification of their protein by interference factors belonging to other cellular compartments. Thus, some mRNP proteins might possess initiation factor or protein synthetic activity if we accept Spirin's theory, i.e., Eukaryotic messenger RNA and informosomes omnia mea mecum porto     

Replication origins, factors and attachment sites

The initiation of eukaryotic DNA synthesis occurs at specific sites determined by both cis- and trans-acting elements. Here I review advances in the characterization of yeast origins, origin-binding proteins and the relationship of DNA replication to nuclear substructure in yeast.