Molecular Targets of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) within the Zebrafish Ovary: Insights into TCDD-induced Endocrine Disruption and Reproductive Toxicity

TCDD is a reproductive toxicant and endocrine disruptor, yet the mechanisms by which it causes these reproductive alterations are not fully understood. In order to provide additional insight into the molecular mechanisms that underlie TCDD\u27s reproductive toxicity, we assessed TCDD-induced transcriptional changes in the ovary as they relate to previously described impacts on serum estradiol concentrations and altered follicular development in zebrafish. In silico computational approaches were used to correlate candidate regulatory motifs with observed changes in gene expression. Our data suggest that TCDD inhibits follicle maturation via attenuated gonadotropin responsiveness and/or depressed estradiol biosynthesis, and that interference of estrogen-regulated signal transduction may also contribute to TCDD\u27s impacts on follicular development. TCDD may also alter ovarian function by disrupting various signaling pathways such as glucose and lipid metabolism, and regulation of transcription. Furthermore, events downstream from initial TCDD molecular-targets likely contribute to ovarian toxicity following chronic exposure to TCDD. Data presented here provide further insight into the mechanisms by which TCDD disrupts follicular development and reproduction in fish, and can be used to formulate new hypotheses regarding previously documented ovarian toxicity

An individual-based model for the Lenski experiment, and the deceleration of the relative fitness

The Lenski experiment investigates the long-term evolution of bacterial populations. Its design allows the direct comparison of the reproductive fitness of an evolved strain with its founder ancestor. It was observed by Wiser et al. (2013) that the relative fitness over time increases sublinearly, a behaviour which is commonly attributed to effects like clonal interference or epistasis. In this paper we present an individual-based probabilistic model that captures essential features of the design of the Lenski experiment. We assume that each beneficial mutation increases the individual reproduction rate by a fixed amount, which corresponds to the absence of epistasis in the continuous-time (intraday) part of the model, but leads to an epistatic effect in the discrete-time (interday) part of the model. Using an approximation by near-critical Galton-Watson processes, we prove that under some assumptions on the model parameters which exclude clonal interference, the relative fitness process converges, after suitable rescaling, in the large population limit to a power law function.Comment: minor changes, additional references, some comments on the notion of relative fitness and on the modelling assumptions adde

Contraceptive Sabotage

This Article responds to the alarm recently sounded by the American College of Obstetricians and Gynecologists over “birth control sabotage”—the “active interference [by one partner] with [the other] partner’s contraceptive methods in an attempt to promote pregnancy.” Currently, sabotage is not a crime, and existing categories of criminal offenses fail to capture the essence of the injury it does to victims. This Article argues that sabotage should be a separate crime—but only when perpetrated against those partners who can and do get pregnant as a result of having sabotaged sex. Using the principle of self-possession—understood as a person’s basic right to self-ownership—this Article argues that women have a self-possessory interest in maintaining their reproductive capacity in its non-pregnant state during and after having sex to the extent they seek to establish with the use or planned use of contraception. Sabotage by sexual partners—typically male—violates this interest and merits criminal punishment. This Article proposes statutory language to criminalize sabotage that should be added to the revision of the Model Penal Code currently underway. Not only would this addition likely survive any Equal Protection challenge, it would arguably serve to strengthen the existing constitutional right to non-procreative sex by setting meaningful limits on one partner’s ability to interfere unilaterally with the other partner’s contraceptive decisions

Evolutionary biology and genetic techniques for insect control

The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutilized methods such as reproductive interference, CRISPR technology, RNA interference (RNAi), and genetic underdominance. We focus on understanding principles and potential effectiveness from the perspective of evolutionary biology. This offers useful insights into mechanisms through which potential problems may be minimized, in much the same way that an understanding of how resistance evolves is key to slowing the spread of antibiotic and insecticide resistance. We conclude that there is much to gain from applying principles from the study of resistance in these other scenarios – specifically, the adoption of combinatorial approaches to minimize the spread of resistance evolution. We conclude by discussing the focused use of GM for insect pest control in the context of modern conservation planning under land-sparing scenarios

Voluntary Sterilization of Inmates for Reduced Prison Sentences

In May 2017, a Tennessee judge issued a standing order allowing inmates to receive thirty days’ jail credit in exchange for undergoing a voluntary sterilization procedure. Although the order was ultimately rescinded, this Article will address the constitutional and ethical concerns that a district court would have considered had the order not been rescinded. While inmates can always choose to waive their constitutional rights, the coercive nature of prisons—explained in the unconstitutional conditions doctrine—may compromise a prisoner’s ability to provide voluntary consent. The constitutionality of the order largely depends on the level of scrutiny a court applies. Regardless of the order’s constitutionality, the adverse ethical and social ramifications outweigh any potential benefits that could come from such an order. This order would also give too much power to state governments over an individual’s reproductive freedoms. Instead of automatically reducing an inmate’s sentence after undergoing a sterilization procedure, drug offenders should have the opportunity to choose from several different birth control options that could possibly lead to a reduced sentence

Wolbachia and arbovirus inhibition in mosquitoes

Wolbachia is a maternally inherited intracellular bacteria that can manipulate the reproduction of their insect hosts, and cytoplasmic incompatibility allows them to spread through mosquito populations. When particular strains of Wolbachia are transferred into certain Aedes mosquito species, the transmission capacity of important arthropod-borne viruses can be suppressed or abolished in laboratory challenges. Viral inhibition is associated with higher densities of transinfecting Wolbachia compared with wild-type strains of the bacterium. The upregulation of innate immune effectors can contribute to virus inhibition in Aedes aegypti, but does not seem to be required. Modulation of autophagy and lipid metabolism, and intracellular competition between viruses and bacteria for lipids, provide promising hypotheses for the mechanism of inhibition. Transinfecting virus-inhibiting strains can produce higher fitness costs than wild-type mosquito Wolbachia; however, this is not always the case, and the wMel strain has already been introduced to high frequency in wild Ae. aegypti populations

Social environment and reproductive interference affect reproductive success in the frog Rana latastei

Variation in the social environment produces selection on morphological and behavioral traits. It is less clear how the social environment generates variation in demography through behavioral mechanisms. Theory suggests that one aspect of social environment, relative abundance of heterospecifics, influences the intensity of reproductive interference and its demographic effects. These effects are countered by species recognition and female preferences. We studied the effects of social environment on reproductive success in replicated, mixed breeding populations of two ranid frogs, Rana latastei and Rana dalmatina, the former being of international conservation concern. We manipulated the social environment of female R. latastei experimentally by varying the relative abundance of potential conspecific and heterospecific sexual partners. We measured amplexus frequency and recorded the reproductive success of R. latastei females. When conspecific males were relatively uncommon, (1) the absolute and relative frequencies of conspecific amplexus decreased, indicating a breakdown of sexual isolation, (2) oviposition was less frequent, and (3) the percentage of viable embryos in deposited clutches decreased. R. latastei females in an environment of low relative conspecific abundance (1:5, R. Latastei:R. dalmatina) demonstrated 6.8% the reproductive success of females in an environment exclusively with conspecifics. We present a model for the dependence of conspecific amplexus on the social environment. We discuss several mechanisms that may influence reproduction by R. latastei, and we support conservation of the species' preferred habitat to reduce opportunities for reproductive interference that occur at shared breeding site

<em>Yearworth v. North Bristol NHS Trust</em>:A Property Case of Uncertain Significance?

It has long been the position in law that, subject to some minor but important exceptions, property cannot be held in the human body, whether living or dead. In the recent case of Yearworth and Others v North Bristol NHS Trust, however, the Court of Appeal for England and Wales revisited the property debate and threw into doubt a number of doctrines with respect to property and the body. This brief article analyses Yearworth, (1) reviewing the facts and the Court's decision with respect to the originators' proprietary and contractual interests in their body and bodily products, (2) considering the significance of relying on property and its use a legal metaphor, (3) questioning the scope of the property right created, and (4) querying whether an alternate conceptual approach to extending rights and a remedy was warranted. It concludes that, while Yearworth engages with, and impacts on, important theoretical and practical issues--from legal, healthcare and research perspectives--it does not offer a great deal of guidance and, for that reason, its precedential significance is in doubt