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Biomedical subjects

John A Robertson

Publications and source records attributed to John A Robertson.

At least 19 recordsLinked to original sources
PubMed2007

The influence of extremely low frequency magnetic fields on cytoprotection and repair.

Ischemia-reperfusion injuries, such as those suffered from various types of cardiovascular disease, are major causes of death and disability. For relatively short periods of ischemia, much of the damage is potentially reversible and in fact, does not occur until the influx of oxygen during the reperfusion stage. Because of this, there is a window of opportunity to protect the ischemic tissue. Here, we review several mechanisms of protection, such as heat shock proteins, opioids, collateral blood flow, and nitric oxide induction, and the evidence indicating that magnetic fields may be used as a means of providing protection via each of these mechanisms. While there are few studies demonstrating direct protection with magnetic field therapies, there are a number of published reports indicating that electromagnetic fields may be able to influence some of the biochemical systems with protective applications.

Analgesics, Opioid↗
PubMed2006

Compensation and egg donation for research.

Financial compensation to egg donors for their time and inconvenience in donating is established in the United States as ethically and legally acceptable. That system should be extended to egg donation for research.

Commodification↗
PubMed2005

Daily repeated magnetic field shielding induces analgesia in CD-1 mice.

We have recently observed that a single exposure of mice to a magnetically shielded environment can attenuate opioid induced analgesia. Here, we report the effect of repeated exposures to the same magnetically shielded environment. Adult male Swiss CD-1 mice were placed in a Mu-metal lined box or an opaque Plexiglas box (sham condition) for 1 h per day for 10 consecutive days. Nociception was measured as the latency time to a foot lift/lick in response to an aversive thermal stimulus (hotplate analgesiometer, 50 +/- 1 degrees C) before and immediately after exposure. Multiple experiments were conducted in which thermal latency was tested on each of the 10 days or on days 1, 5, and 10, with some utilizing post-exposure testing only. It was shown that mice can detect and will respond to the repeated absence of the ambient magnetic field, with a maximum analgesic response occurring over days 4-6 of exposure and returning to baseline thereafter. The effect was robust, independent of pre-exposure and intermittent testing, and seems to be opioid related, since the results obtained on day 5 were similar to those from a 5 mg/kg dose of morphine and were abolished with the opioid antagonist, naloxone.

Analgesia↗
PubMed2005

Ethics and the future of preimplantation genetic diagnosis.

The future growth of preimplantation genetic diagnosis (PGD) will depend on refinements in genetic knowledge and genetic analysis of blastomeres. Equally important, however, is an acceptance of the ethical legitimacy of parents using technologies to select genetic traits of offspring. Objections based on embryo status, the giftedness of reproduction, eugenics, and protecting the child's welfare are not convincing grounds to oppose most uses of PGD. Whether PGD should be accepted for new medical or non-medical uses should depend upon a careful assessment of the proposed use's importance to the person or couple requesting it, and the harmful effects, if any, which it might cause. Such an approach leads to the conclusion that most new medical uses of PGD and some non-medical uses should be permitted.

Deafness↗
PubMed2005

Cancer and fertility: ethical and legal challenges.

Preserving the fertility of younger cancer patients requires coordinated efforts and attention to ethical issues by oncologists and fertility specialists. Although sperm is easily stored, freezing eggs or ovarian tissue is still experimental and should not be offered except as part of an experimental protocol. When gametic material is stored for later use, written directives for posthumous use may be given effect, and subsequently born children may be recognized as legal offspring of the deceased. Concerns about the welfare of offspring resulting from an expected shortened life span of the parent are not sufficient reason to deny cancer survivors assistance in reproducing.

Adult↗
PubMed2004

Protecting embryos and burdening women: assisted reproduction in Italy.

BACKGROUND: A new law in Italy imposes strict conditions on assisted reproduction at a time when many other countries have become more accepting of these techniques. The law has been criticized both in and outside of the country because of its excessive concern with the status of embryos and disregard for the interests of women and infertile couples. METHODS: Bioethical, legal and policy analysis based on published materials. RESULTS AND CONCLUSIONS: This article shows that ethical concerns about respect for human life and protection of the family and offspring need not burden women and infertile couples to the extent that the new Italian law does. Defining embryos as existing only at syngamy, allowing unpaid sperm and oocyte donation, and permitting the screening of embryos for genetic disease would greatly improve the situation of infertile women in Italy without greatly compromising the values and goals of the Italian law.

Embryo, Mammalian↗
PubMed2004

Gender variety as a valid choice: a comment on the HFEA - response to Edgar Dahl's 'The presumption in favour of liberty'.

The Human Fertilisation and Embryology Authority (HFEA) has made several sensible recommendations about sperm sorting and preimplantation genetic diagnosis for sex selection, but has not provided a convincing case for restricting all non-medical uses of sex selection techniques. It relies too much on a public opinion survey and speculative fears about bad outcomes for offspring, and overlooks the legitimate interest of some families in using such techniques to have offspring of different genders.

Ethics, Medical↗
PubMed2003

Extending preimplantation genetic diagnosis: the ethical debate. Ethical issues in new uses of preimplantation genetic diagnosis.

The use of preimplantation genetic diagnosis (PGD) to screen embryos for aneuploidy and genetic disease is growing. New uses of PGD have been reported in the past year for screening embryos for susceptibility to cancer, for late-onset diseases, for HLA-matching for existing children, and for gender. These extensions have raised questions about their ethical acceptability and the adequacy of regulatory structures to review new uses. This article describes current and likely future uses of PGD, and then analyses the ethical issues posed by new uses of PGD to screen embryos for susceptibility and late-onset conditions, for HLA-matching for tissue donation to an existing child, and for gender selection. It also addresses ethical issues that would arise in more speculative scenarios of selecting embryos for hearing ability or sexual orientation. The article concludes that except for sex selection of the first child, most current extensions of PGD are ethically acceptable, and provides a framework for evaluating future extensions for nonmedical purposes that are still speculative.

Genetic Predisposition to Disease↗
PubMed2003

The $1000 genome: ethical and legal issues in whole genome sequencing of individuals.

Progress in gene sequencing could make rapid whole genome sequencing of individuals affordable to millions of persons and useful for many purposes in a future era of genomic medicine. Using the idea of $1000 genome as a focus, this article reviews the main technical, ethical, and legal issues that must be resolved to make mass genotyping of individuals cost-effective and ethically effective. It presents the case for individual ownership of a person's genome and its formation, and shows the implications of that position for rights to informed consent and privacy over sequencing, testing, and disclosing genomic information about identifiable individuals. Legal recognition of a person's right to control his or her genome and the information that it contains is essential for further progress in applying genomic discoveries to human lives.

Adult↗