This essay presents a hypothesis which contends that the development of organismic complexity in the eukaryotes depended extensively on propagation via flagellated and ciliated gametes. Organisms utilizing flagellate and ciliate gametes to propagate their germ line have contributed most of the organismic complexity found in the higher animals. The genes of the flagellum and the flagellar assembly system (intraflagellar transport) have played a disproportionately important role in the construction of complex tissues and organs. The hypothesis also proposes that competition (...) between large numbers of haploid flagellated male gametes rigorously conserved the functionality of a key set of flagellar genes for more than 700 million years. This in turn has insured that a large set (>600) of highly functional cytoskeletal and signal pathway genes is always present in the lineage of organisms with flagellated or ciliated gametes to act as a dependable resource, or “toolkit,” for organ elaboration. Also see the video abstract here: https://youtu.be/lC5nC-WOcm8. (shrink)

The first reported case of postmortem sperm retrieval occurred in 1978, involving a man who became brain dead after a motor vehicle accident and whose wife requested removal of his sperm so that she could be artificially inseminated. Physicians performed the retrieval by surgically excising the ducts that transport sperm from the testes and removing sperm from them. Since that time, several other methods for retrieving sperm from such patients have been reported, and at least 141 cases have been (...) documented in which requests were made for removal of sperm from men who were dead or irreversibly unconscious. Moreover, there have been several reports of pregnancies and births resulting from assisted reproduction using sperm retrieved in such cases. (shrink)

The global distribution of laboratory mouse strains is valued for ensuring the continuity, validity and accessibility of model organisms. Mouse strains are therefore assumed mobile and able to travel. We draw on the concept of ‘animal mobilities’ to explain how attending to laboratory mice as living animal, commodity and scientific tool is shaping how they are transported through contemporary scientific infrastructures and communities. Our paper is framed around exploring how animal strains travel, rather than animals, as we show that it (...) is only through understanding strain mobility that we can explain how and why live animal movement can be replaced by germinal products. The research is based on qualitative fieldwork in 2018 and 2019 that included 2 weeks ethnography and interviews with key informants involved in the movement of laboratory animals. The empirical analysis discusses practices that relate to managing biosecurity and animal welfare concerns when moving laboratory animal strains. In closing we reflect more broadly on the contemporary ‘ethico-onto-epistemological’ entanglement that shapes who or what travels to support laboratory science data-making practices, and the intensity of care ‘tinkering’ practices that facilitate the movement. We explain how a laboratory animal strain exceeds its value solely as a mobile and thus exchangeable commodity, illustrated in how values that relate to animal sentience and infection-risk supports its material transformation. Consequently, it is becoming increasingly common for non-sentient germinal products – embryos and gametes - to replace live sentient animals when being moved. (shrink)

Artificial gametes, derived from stem cells, have the potential to enable in vitro fertilization of embryos. Currently, artificial gametes are only being generated in laboratory animals; however, considerable efforts are underway to develop artificial gametes using human cell sources. These artificial gametes are being proposed as a means to address infertility through assisted reproductive technologies. Nonetheless, the availability of artificial gametes obtained from adult organisms can potentially expand the possibilities of reproduction. Various groups, such as same-sex couples, post-menopausal women, and (...) deceased donors, could potentially utilize artificial gametes to conceive genetically related offspring. The advent of artificial gametes raises significant bioethical questions. Should all these reproductive scenarios be accepted? How can we delineate the range of future reproductive choices? A normative bioethical framework may be necessary to establish a consensus regarding the use of human artificial gametes. This review aims to present the current state of research on the biological roadmap for generating artificial gametes, while also summarizing proposed approaches to establish a normative framework that delineates ethically acceptable paths for reproduction. (shrink)

What is the relationship between the position that anonymous gamete donation is wrong (i.e. the anti-anonymity position) and the position that all gamete donation is wrong (i.e. the anti-donation position)? Some argue that people who accept the anti-anonymity position should also accept the anti-donation position on the grounds that the two positions share the same main arguments. But that’s not true. One argument in favor of anti-anonymity does not generate genuine dialectical pressure to accept the anti-donation position. The (...) other anti-anonymity arguments do generate dialectical pressure, but not in a way that pushes toward the anti-donation position. Instead, they push toward what we might call the ‘pro-known-donation’ position. So, either there is no dialectical pressure or, where there is, it doesn’t flow toward the anti-donation position. (shrink)

Gamete donation offers a unique opportunity to compare men and women's relationships to reproductive decision-making, unlike other reproductive processes, which typically involve women's bodies much more asymmetrically. I address medical and reproductive decision-making by examining how a gamete donor's partner may be involved in the donation process. Some countries explicitly involve a donor's partner by legally requiring spousal consent for donation, but this is not the case for the U.S. In the absence of any formal regulation, what are (...) the expectations for involving a donor's partner? Through a content analysis of materials from donation programs across the U.S., I examine how donation programs configure the partner's role. Overall, I find that there are quite different expectations for partner involvement in egg versus sperm donation. Such differences, I argue, both stem from and reinforce existing issues navigating boundaries between intimate relationships and women's medical and reproductive autonomy. (shrink)

This article surveys a range of recent media storiesabout human gametes, pinning them to a series of widerpreoccupations within late modern life. Threepreoccupations are singled out: first, kinship andrelational identity; secondly, Nature andglobalisation; and finally, sexual difference andequality. Each one of these preoccupations has beencharacterised as iconic; debates about them are saidto crystallise who we are, especially ouruncertainties, and what we will be in the future. Byindexing these preoccupations to the stories abouthuman gametes, the article aims to upset both theincreasing (...) attempts to present assisted reproductiontechnologies as `familiar' (as Nature's `helpinghand', for example) and the recurringassumptions about this technology's alleged`novelty' and `anomaly'. The article concludesthat treating reproduction technologies, and theirregulation, as `familiar' risks complacency:equally, assumptions about their `novelty' narrowsthe search for effective explanatory tools andregulatory mechanisms. The upshot is that it might bebest for us to view reproductive technologies as bothless `familiar' and less `novel'. (shrink)

Brussen, Kerri Anne Children born through gamete donation can be genetically linked to one or neither parent. This article examines the practice of gamete donation, seeking to establish if there is cause for concern.

Unlike surrogacy and cloning, reproduction via gamete donation is widely assumed to be morally unproblematic. Recently, a number of authors have argued that this assumption is mistaken: gamete donors, they claim, have parental responsibilities that they typically treat too lightly. In this paper I argue that the ‘parental neglect’ case against gamete donation fails. I begin by examining and rejecting the view that gamete donors have parental responsibilities; I claim that none of the current accounts of (...) parenthood provides good reason for ascribing parenthood to gamete donors. I then argue that even if gamete donors do have parental responsibilities for ‘their’ children, it is not clear that they treat these responsibilities too lightly. I conclude the paper by examining the wider question of just what kind of responsibilities gamete donors might have towards the children that they have a role in creating. (shrink)

A number of recent papers have described the successful derivation of egg and sperm precursor cells from mouse embryonic stem cells—so-called “artificial” gametes. Although many scientific questions remain, this research suggests numerous new possibilities for stem cell research and assisted reproductive technology, if a similar breakthrough is achieved with human embryonic stem cells. The novel opportunities raised by artificial gametes also prompt new ethical questions, such as whether same-sex couples should be able to access this technology to have children who (...) are genetically related to them both.THE CREATION OF “ARTIFICIAL” GAMETESOver the past two years, a number of papers have been published detailing the first successful attempts at differentiating mouse embryonic stem cells into egg1 and sperm2 precursor cells. Previously, researchers had used embryonic stem cells to generate tissues such as brain, liver, and pancreatic cells, but not germ cells of any kind. Production of gamete precursor cells was achieved initially through allowing stem cell lines to differentiate more or less randomly, but recent research has focused on identifying the precise ways in which differentiation into gametes can be precipitated and controlled. These breakthroughs make it seem likely that ongoing research on human stem cells will yield similar possibilities,3 raising questions over the practicalities of what might be achieved with such “artificial” gametes. In turn, the novel opportunities presented by artificial gametes raise a number of ethical concerns.The initial breakthrough, namely the obtaining of egg cells from mouse stem cells, was achieved by means of relatively simple science. Rather than coaxing stem cells to develop into eggs using complicated cocktails of growth factors, researchers adopted standard cell culture conditions, but grew the cells at higher density than usual.3–6 Growing the cells in this way led to the formation of ovary-like cell aggregates, which (when separated and stimulated with …. (shrink)

According to Rivka Weinberg, gametes are like enriched uranium: both are hazardous materials. Exposing human beings to enriched uranium can result in radioactivity and decreased life expectancy, while exposing sperm and ova to each other can result in the creation of needy innocent persons with full moral status. Weinberg argues that when we engage in activities that put our gametes at risk of joining with others and growing into persons, we assume the costs of that risky activity. She calls this (...) the Hazmat Theory of parental responsibility. The theory is novel and important, and has far-reaching consequences for the ethics of procreation, parenting, and population, implying among other things that that the only way to avoid acquiring parental responsibilities may be to “abstain from sexual intercourse or surgically interfere with our gamete-release system.” For these reasons the theory merits careful scrutiny. In this article I criticize the theory's account of how parental responsibility is acquired and its treatment of the standard of care expected of gamete possessors, and argue that it fails to properly account for a distinction between procreative costs and parental responsibility. Even if gametes are hazardous, it does not follow that parental responsibility in Weinberg's sense is acquired whenever one brings new persons into existence. (shrink)

Actors, undercover investigators, and readers of fiction sometimes report “losing themselves” in the characters they imitate or read about. They speak of “taking on” or “assuming” the beliefs, thoughts, and feelings of someone else. I offer an account of this strange but familiar phenomenon—what I call imaginative transportation.

A growing number of jurisdictions hold that gamete donors must be identifiable to the children born with their eggs or sperm, on grounds that being able to know about one's genetic origins is a fundamental moral right. But the argument for that belief has not yet been adequately made.

In debates on the ethics of artificial gametes, concepts of naturalness have been used in a number of different ways. Some have argued that the unnaturalness of artificial gametes means that it is unacceptable to use them in fertility treatments. Others have suggested that artificial gametes are no less natural than many other tissues or processes in common medical use. We suggest that establishing the naturalness or unnaturalness of artificial gametes is unlikely to provide easy answers as to the acceptability (...) of using them in fertility medicine. However, we also suggest that we should be cautious about repudiating any relationship between nature and moral evaluation. The property of being natural or man-made may not per se tell us anything about an entity’s moral status, but it has an important impact on the moral relationship between the creator and the created organism. (shrink)

Several threads of research towards developing artificial gametes are ongoing in a number of research labs worldwide. The development of a technology that could generate gametes in vitro has significant potential for human reproduction, and raises a lot of interest, as evidenced by the frequent and extensive media coverage of research in this area. We have asked researchers involved in work with artificial gametes, ethicists, and representatives of potential user groups, how they envisioned the use of artificial gametes in human (...) reproduction. In the course of three focus groups, the participants commented on the various aspects involved. The two recurring themes were the strength of the claim of becoming a parent genetically, and the importance of responsible communication of science. The participants concurred that (a) the desire or need to have genetic offspring of one’s own does not warrant the investment of research resources into these technologies, and that (b) given the minefield in terms of moral controversy and sensitivity that characterises the issues involved, how information is communicated and handled is of great importance. (shrink)

There has been a troublesome anomaly in the UK between cash payment to men for sperm donation and the effective assumption that women will pay to donate eggs. Some commentators, including Donald Evans in this journal, have argued that the anomaly should be resolved by treating women on the same terms as men. But this argument ignores important difficulties about property in the body, particularly in relation to gametes. There are good reasons for thinking that the contract model and payment (...) for gametes are both inappropriate, and that a model based on altruism should be applied to both sexes. (shrink)

In this paper we will look at the various ways in which infertility can be understood and at how need for reproductive therapies can be construed. We will do this against the background of research with artificial gametes. Having explored these questions we will attempt to establish the degree to which technologies such as AGs could expand the array of choices that people have to reproduce and/or become parents. Finally, we will examine whether and in what ways the most promising (...) developments of such technologies are likely to bring about the “end of infertility”. (shrink)

The proposal for reproducing human generations in vitro raises the question to what extent parenthood is possible in embryos and to what extent human rights and interests are dependent on conscious awareness. This paper argues that the interest in not being made a parent non-consensually for the benefit of others persists throughout the lifespan of the individual human organism. We do not become genetic parents by learning that we are parents; rather, we discover (or fail to discover) an existing genetic (...) relationship between our offspring and ourselves. The claim to genetic parenthood of an embryo used for reproduction in vitro is, if anything, clearer than the claim of the adult for whom gametes are derived via ips cells, in that an embryo’s cells, unlike an adult’s somatic cells, are already functionally geared to producing gametes (among other types of cell). An embryo used to make gametes that are used in reproduction is immediately and non-consensually made a genetic parent and to that extent is wronged whether or not the parent embryo survives – as some could survive – the harvesting of cells. All human individuals carry objective interests in benefits appropriate to the kind of being they are; these include the stake in not being made a parent without one’s consent, whether posthumously or otherwise. (shrink)

In Southeast Asian countries (SEA), road transport accounts for the main energy consumption and CO2 emission. Air pollution is a major concern in densely populated cities such as Bangkok, Manila, and Kuala Lumpur. The main objective of this paper is to give insights on trends of transport development, car ownership, and CO2 emissions in Southeast Asia. This study also attempts to review the successful transportation policies around the globe and to introduce the possible instruments that can help reduce (...) air pollution in Southeast Asian countries. Economic instruments to estimate the benefits of a cleaner environment due to new policies are introduced as well. The results of this research could help policy makers consider approaches that could internalize external costs of transportation and maximize the societal welfare. (shrink)

Citrate, an organic trivalent anion, is a major substrate for generation of energy in most cells. It is produced in mitochondria and used either in the Krebs' cycle or released into cytoplasm through a specific mitochondrial carriers. Citrate can also be taken up from blood through different plasma membrane transporters. In the cytoplasm, citrate can be used ultimately for fatty acid synthesis, which is increased in cancer cells. Here, we review the ways in which citrate can be transported and discuss (...) the changes in transport and metabolism that occur in cancer cells. The primary focus is on the prostate gland, which is known to produce and release large amounts of citrate during its normal secretory function. The significant changes that occur in citrate‐related metabolism and transport in prostate cancer are the second focus. This review strives to relate these mechanisms to molecular biology on the one hand and to clinical applications on the other. (shrink)

Fertilization is the result of a series of successful recognition and binding events mediated by gamete surface molecules. Recent advances in the identification and characterization of some of these recognition molecules provide extremely valuable information necessary to understand sperm‐egg recognition and subsequent egg activation. We discuss these new data in the context of the model of gamete recognition first proposed by F.R. Lillie in the early part of the 20th century, and revisited periodically in the subsequent literature, which (...) relates fortilization events to those of immune cell recognition and activation events. Here we discuss the principles underlying the molecular recognition and activation mechanisms of gametes and immune cells. (shrink)

There is a lack of consensus on whether the derivation and use of human embryonic stem cells (hESCs) from embryos remaining after infertility treatment morally require the informed consent of third-party gamete donors who contributed to the creation of the embryos. The principal guidelines for oversight and funding of hESC research in the United States make minimal or no demands for consent from gamete donors. In this article, I consider the arguments supporting and opposing gamete donor consent (...) for hESC research and embryo research more broadly. I argue that it is not morally permissible to use leftover embryos in research without the informed consent of gamete donors, and that we should place restrictions on the use of existing hESC lines that may have been derived without informed consent. While the standard argument for this position relies on an appeal to gamete donors’ interest in controlling what happens with their genetic material, I identify shortcomings with the standard approach and seek instead to locate the deeper moral foundations for gamete donor consent in rights to bodily integrity. (shrink)

This chapter contains sections titled: The Transportation System Transportation System Benefits, Harms and Hazards Conclusions and Further Questions References and Further Reading.

Some commentators indirectly challenge the ethics of using synthetic gametes as a way for same-sex couples to have children with shared genetics. These commentators typically impose a moral burden of proof on same-sex couples they do not impose on opposite-sex couples in terms of their eligibility to have children. Other commentators directly raise objections to parenthood by same-sex couples on the grounds that it compromises the rights and/or welfare of children. Ironically, the prospect of synthetic gametes neutralises certain of these (...) objections, insofar as they would ensure that children have parents whom they can know as their genetic parents, which outcome is not always possible when same-sex couples involve third parties as the source of gametes or embryos. Not all commentators in bioethics throw the use of synthetic gametes into doubt as far as same-sex couples are concerned, but even these commentators put parenting by gay men and lesbians at the conclusion of an argument rather than presupposing parental legitimacy from the outset. Synthetic gametes do raise questions of ethics in regard to parenthood for gay men and lesbians, but these are largely questions of access and equity, not questions of parental fitness and/or child welfare. (shrink)

Sophisticated arguments advanced by Harry Silverstein, David Boonin, and Jeff McMahan attempt to show that being responsible for an individual's existence need not result in an obligation to ensure that the needs of that individual are satisfied. While these arguments take place within the abortion debate, by extension they threaten causal accounts of procreative responsibility more generally. In this article, I defend causal accounts of procreative responsibility by showing that these arguments do not succeed, but without thereby undermining the permissibility (...) of abortion. Further, while being causally involved in the existence of a person is not sufficient for acquiring procreative responsibilities, I argue that there is an especially strong case for ascribing such responsibilities to gamete donors. (shrink)

The growing scope of gamete donation and themanipulation of gametes makes it essential to developa coherent theory of the nature of gametes and theclaims which may be made in relation to them. Thenature of gametes is ambiguous, they blur thedistinctions between persons and property, but thecurrent legal framework which governs gamete donationand manipulation fails to address their status. Thisleaves unanswered fundamentally important questionsabout control of processes involving gametes andrights to use or control the gametes themselves andthe information which (...) they represent. These areclaims which are rooted in the concept ofproperty. A property based analysis highlights thethemes of autonomy, personhood and control which lieat the heart of the claims made in relation to gametesand an account based on the notion of property forpersonhood offers a more coherent justification forrecognising claims in gametes and mediating disputes. This perspective exposes the inadequacies andinconsistencies of the legal construction of gametesand the legal regulation of gamete donation. Thepresent legal framework has not sought to develop acoherent construction of gametes, but to constrain thepractices of the assisted reproductive technologies(including gamete donation) within a framework whichis presented as least damaging to the traditionalideologies of the creation of the family. (shrink)

This paper argues that the convention of allocating donated gametes on a ‘first come, first served’ basis should be replaced with an allocation system that takes into account more morally relevant criteria than waiting time. This conclusion was developed using an empirical bioethics methodology, which involved a study of the views of 18 staff members from seven U.K. fertility clinics, and 20 academics, policy-makers, representatives of patient groups, and other relevant professionals, on the allocation of donated sperm and eggs. Against (...) these views, we consider some nuanced ways of including criteria in a points allocation system. We argue that such a system is more ethically robust than ‘first come, first served’, but we acknowledge that our results suggest that a points system will meet with resistance from those working in the field. We conclude that criteria such as a patient's age, potentially damaging substance use, and parental status should be used to allocate points and determine which patients receive treatment and in what order. These and other factors should be applied according to how they bear on considerations like child welfare, patient welfare, and the effectiveness of the proposed treatment. (shrink)

Ovarian tissue transplantation is an experimental procedure that can be used to treat both infertility and premature menopause. Working within the current legal framework in the USA, I examine whether ovarian tissue should be legally treated like gametes or organs in the case of ovarian tissue transplantation between two women. One option is to base classification upon its intended use: ovarian tissue used to treat infertility would be classified like gametes, and ovarian tissue used to treat premature menopause would be (...) classified like organs. In the end, however, I argue that this approach will not work because it engenders too many legal, cultural and logistical concerns and that, at least for the near future, we should treat ovarian tissue like gametes. (shrink)

Anonymous gamete donation continues to be practised in most jurisdictions around the world, but this practice has come under increased scrutiny. Thus, several countries now mandate that donors be identifiable to their genetic offspring. Critics contend that anonymous gamete donation harms the interests of donor-conceived individuals and that protection of these interests calls for legal prohibition of anonymous donations. Among the vital interests that critics claim are thwarted by anonymous donation are an interest in having a strong family (...) relationship, health interests, and an interest in forming a healthy identity. This article discusses each of these interests and examines what they could involve. The legislation in two countries is considered: Spain, which mandates anonymous gamete donation, and the UK, which prohibits such practice, to assess how these different legislations might or might not protect these vital interests. (shrink)

The transport of molecules across the nuclear envelope plays a central role in the metabolism of the cell. Significant advances hi three major areas highlight the limits of our current knowledge and point to the prospect of exciting future developments. Firstly, findings that ions and small proteins do not diffuse freely into the nucleus call into question the current views of nuclear envelope permeability. Secondly, indications that nuclear protein import can be regulated in conjunction with the cell cycle and (...) development have been confirmed by the clear demonstration of regulated nuclear entry of specific transcription factors and morphogens. Thirdly, identification and characterisation of candidate receptor proteins indicates that the recognition of the nuclear targeting sequence occurs in the cytoplasm, suggesting that a different recognition event occurs at the nuclear pore. (shrink)

It has been suggested that future application of stem-cell derived gametes might lead to the possibility for same-sex couples to have genetically related children. Still, for this to become possible, the technique of gamete derivation and techniques of reprogramming somatic cells to a pluripotent state would have to be perfected. Moreover, egg cells would have to be derived from male cells and sperm cells from female cells, which is believed to be particularly difficult, if not impossible. We suggest a (...) more plausible scenario to provide same-sex couples with the possibility to parent a child who is genetically related to both parents. Although technical feasibility is an advantage, disadvantages are that cooperation of a donor of the opposite sex is still required and that the partners are genetically linked to the resulting child in a different degree. However, since in our scenario the donor's genetic contribution would not outweigh any of the parents' genetic contribution, this alternative route may ease the fear for a possible parental claim by the donor. Like many other applications in the field of infertility treatment, the goal to create SCD-gametes for reproductive purposes is largely based on the high value attributed to genetic parenthood. Although we believe that genetic relatedness is neither a necessary nor a sufficient condition for ‘good’ parenthood, we do believe that many people may consider our scenario a welcome alternative. (shrink)

Current developments in reproductive technology forecast that in the foreseeable future artificially generated gametes might be presented as a possible fertility treatment for infertile couples and for homosexual couples desiring to have children genetically originating from both partners. It is important to evaluate the ethical issues connected to this technology before its emergence. This article first reviews the meaning that gametes (sperm and eggs) might have to those who procreate, as well as their ontology. From this, suggestions are made as (...) to what qualities artificially generated gametes need to be truly called gametes. Finally, different proposed routes for artificial gamete generation are examined on the basis of these qualities, with their prospective problems and advantages highlighted. Autotransplanted gametes (or their progenitors) generated solely from patient-derived tissue are deemed to be the most ethically suitable route for the development of this technology. (shrink)

El autor realiza un amplio recorrido sobre los estudios del transporte público en Santiago, analizado como un tema de calidad de vida. Para ello ocupa una metodología y estadísticas de elaboración propia a partir de información contenida en dos diarios nacionales. Se concluye que el servicio está por debajo de lo mínimamente aceptable, generando múltiples problemas e incomodidades a los usuarios, llevando esto a una presión por el incremento de la adquisición de vehículos particulares.

Adenosine transport in cultured human umbilical vein endothelial cells (HUVEC) was characterized and shown to be mediated by a single facilitated diffusion mechanism. Initial rates of adenosine influx at 22 degrees C were saturable [apparent Michaelis constant, 69 +/- 10 mu M; maximum velocity (V-max), 600 +/- 70 pmol.10(6) cells(-1).s(-1)] and inhibited by nitrobenzylthioinosine (NBMPR). Formycin B had an unusually high affinity [inhibitory constant K-i), 18 +/- 4.3 mu M], whereas inosine had a low affinity (K-i, 440 +/- 68 (...) mu M) and nucleobases were without effect on adenosine influx. The number of transporters (1.2 x 10(6) sites/cell) was estimated by NBMPR equilibrium binding (apparent dissociation constant, 0.11 +/- 0.01 nM; maximum binding, 2.0 +/- 0.15 pmol/10(6) cells). In addition, we compared these endothelial cells with those obtained from cords from pregnancies complicated by diabetes (HUVEC-D), since embriopathy may occur in these conditions. HUVEC-D exhibited a 2.3-fold reduction in both the V-max for adenosine influx and the maximum number of NBMPR binding sites (260 +/- 40 pmol.10(6) cells(-1).s(-1) and 0.86 +/- 0.08 pmol/10(6) cells, respectively). However, the turnover number for each nucleoside transporter in normal and diabetic HUVEC was similar (approximate to 300 adenosine molecules/s). Adenosine metabolism at 10 mu M in HUVEC-D was modified compared with normal cells. Intracellular phosphorylation (> 90%) was the predominant pathway in normal HUVEC, whereas in HUVEC-D, substantial levels of adenine and adenosine were detected. The present results demonstrate therefore the downregulation of the NBMPR-sensitive nucleoside transporter and changes in adenosine metabolism in HUVEC from diabetic pregnancies. (shrink)

Gamete donation from third parties is controversial in China as it severs blood ties, which are considered of utmost importance in Confucian tradition. In recent years, infertile couples are increasingly demonstrating a preference for the use of gametes donated by family members to conceive children—known as “intra-family gamete donation.” The main advantage of intra-family gamete donation is that it maintains blood ties between children and both parents. To date there is no practice of intra-family gamete donation (...) in China. In this paper, we investigate intra-family adoption in China in order to illustrate that intra-family gamete donation is consistent with Confucian tradition regarding the importance of maintaining blood ties within the family. There are several specific ethical issues raised by intra-family gamete donation. It may, for example, result in consanguinity and the semblance of incest, lead to confused family relationships, and raise concerns about possible coercion of familial donors. Confucian tradition provides a new approach to understand and deal with these ethical issues in a way that Western tradition does not. As a result, we suggest intra-family gamete donation could be an acceptable solution to the problem of infertility in China. However, further discussion and open debates on the ethical issues raised by intra-family gamete donation are needed in China. (shrink)

The recent success in generating live offspring from embryonic stem cell –derived gametes in mice sparked visions of growing tailor-made sperm for men faced with infertility. However, although this development will almost certainly lead to new insights into the processes underlying spermatogenesis and thus in the possible causes of male infertility, it is less certain if deriving sperm from ES cells, which are in turn derived from a sterile man, can make someone a genetic parent. As the gap between newly (...) envisioned reproductive technologies and natural reproduction widens, the question thus needs to be asked if these possible therapies still lead to genetic parenthood. (shrink)

The recent in vitro derivation of gamete‐like cells from mouse embryonic stem (mES) cells is a major breakthrough and lays down several challenges, both for the further scientific investigation and for the bioethical and biolegal discourse. We refer here to these cells as gamete‐like (sperm‐like or oocyte‐like, respectively), because at present there is still no evidence that these cells behave fully like bona fide sperm or oocytes, lacking the fundamental proof, i.e. combination with a normally derived gamete (...) of the opposite sex to yield a normal individual. However, the results published so far do show that these cells share some defining features of gametes. We discuss these results in the light of the bioethical and legal questions that are likely to arise would the same process become possible with human embryonic stem (hES) cells. (shrink)

In their paper Hortonet alargue that it is acceptable to contact an anonymous egg-donor to facilitate diagnostic genetic testing for the donor conceived child, despite the donor, ‘indicating on a historical consent form that she did not wish to take part in future research, and that she did not wish to be informed if she was found to be a carrier of a “harmful inherited condition”’. There are a number of claims embedded in Hortonet al’s position that it is acceptable (...) to contact the donor and request that she at least think about participating in genetic testing. In this response. I will go through their main claims and argue that the area of genomic medicine does not justify exceptions to general consent conditions as the authors suppose and conclude that the donor should not be contacted. I will then go on to suggest a policy change that would address Hortonet al’s concerns but would not involve over-riding any previously expressed wishes. (shrink)

The recent in vitro derivation of gamete‐like cells from mouse embryonic stem (mES) cells is a major breakthrough and lays down several challenges, both for the further scientific investigation and for the bioethical and biolegal discourse. We refer here to these cells as gamete‐like (sperm‐like or oocyte‐like, respectively), because at present there is still no evidence that these cells behave fully like bona fide sperm or oocytes, lacking the fundamental proof, i.e. combination with a normally derived gamete (...) of the opposite sex to yield a normal individual. However, the results published so far do show that these cells share some defining features of gametes. We discuss these results in the light of the bioethical and legal questions that are likely to arise would the same process become possible with human embryonic stem (hES) cells. (shrink)

We all know that problems of transportation and allocation appear frequently in practical life. We need to transfer materials from production centers to consumption centers to secure the areas’ need for the transported material or allocate machines or people to do a specific job at the lowest cost, or in the shortest time. We know that the cost factors Time is one of the most important factors that decision-makers care about because it plays an “important” role in many of the (...) practical and scientific issues that we face in our daily lives, and we need careful study to enable us to avoid losses. For this, the linear programming method was used, which is one of the research methods. Processes, where the problem data is converted into a linear mathematical model for which the optimal solution achieves the desired goal. Since these models are linear models, we can solve them using the direct simplex method and its modifications, but the specificity that these models enjoy has enabled scholars and researchers to find special methods that help us in obtaining the optimal solution. Whatever the method used, the goal is to determine the number of units transferred from any material from production centers to consumption centers, or to allocate a machine or person to do a job so that the cost or time is as short as possible. These issues were addressed according to classical logic, but the ideal solution was a specific value appropriate to the conditions in which the data was collected and does not take into account the changes that may occur in the work environment. In order to obtain results that are more accurate and enjoy a margin of freedom, we present in this book a study of transport issues and neutrosophic allocation issues and some methods for solving them. By neutrosophic issues we mean These are the problems in which the data are neutrosophic values, i.e. the required quantities and the available quantities. (shrink)

The recent in vitro derivation of gamete‐like cells from mouse embryonic stem (mES) cells is a major breakthrough and lays down several challenges, both for the further scientific investigation and for the bioethical and biolegal discourse. We refer here to these cells as gamete‐like (sperm‐like or oocyte‐like, respectively), because at present there is still no evidence that these cells behave fully like bona fide sperm or oocytes, lacking the fundamental proof, i.e. combination with a normally derived gamete (...) of the opposite sex to yield a normal individual. However, the results published so far do show that these cells share some defining features of gametes. We discuss these results in the light of the bioethical and legal questions that are likely to arise would the same process become possible with human embryonic stem (hES) cells. (shrink)

According to the causal theory of parenthood, people incur parental obligations by causing children to exist. Proponents of the causal theory often argue that gamete donors have special obligations to their genetic offspring. In response, many defenders of current gamete donation practices would reject the causal theory. In particular, they may invoke the ‘too many parents problem’: many people who causally contribute to the existence of children – for instance, fertility doctors – do not thereby incur parental obligations. (...) This article argues that the conclusions commonly drawn by causal theorists, and by their critics, are premature. Causal theorists have a promising response to the too many parents problem. This response, however, defuses the moral concern that many causal theorists have raised about gamete donation. A similar point, it is argued, applies to Rivka Weinberg’s ‘Hazmat Theory’. -/- . (shrink)