Surgical, ethical, and psychosocial considerations in human head transplantation

A Scoping Review of Professionalism in Neurosurgery

BACKGROUND AND OBJECTIVES

The Accreditation Council for Graduate Medical Education's Milestones provides a foundation for professionalism in residency training. Specific professionalism concepts from neurosurgery could augment and expand milestones for the specialty. We reviewed the current literature and identified professionalism concepts within the context of neurosurgical practice and training.

METHODS

We used a scoping review methodology to search PubMed/MEDLINE and Scopus and identify English-language articles with the search terms "professionalism" and "neurosurgery." We excluded articles that were not in English, not relevant to professionalism within neurosurgery, or could not be accessed. Non-peer-reviewed and qualitative publications, such as commentaries, were included in the review.

RESULTS

A total of 193 articles were included in the review. We identified 6 professionalism themes among these results: professional identity (n = 53), burnout and wellness (n = 51), professional development (n = 34), ethics and conflicts of interest (n = 27), diversity and gender (n = 19), and misconduct (n = 9).

CONCLUSION

These 6 concepts illustrate concerns that neurosurgeons have concerning professionalism. Diversity and gender, professional identity, and misconduct are not specifically addressed in the Accreditation Council for Graduate Medical Education's Milestones. This review could be used to aid the development of organizational policy statements on professionalism.

Current opinion: advances in machine perfusion and preservation of vascularized composite allografts - will time still matter?

PURPOSE OF REVIEW

A major hurdle hindering more widespread application of reconstructive transplantation is the very limited cold ischemia time (CIT) of vascularized composite allografts (VCAs). In this review, we discuss cutting edge machine perfusion protocols and preservation strategies to overcome this limitation.

RECENT FINDINGS

Several preclinical machine perfusion studies have demonstrated the multifactorial utility of this technology to extend preservation windows, assess graft viability prior to transplantation and salvage damaged tissue, yet there are currently no clinically approved machine perfusion protocols for reconstructive transplantation. Thus, machine perfusion remains an open challenge in VCA due to the complexity of the various tissue types. In addition, multiple other promising avenues to prolong preservation of composite allografts have emerged. These include cryopreservation, high subzero preservation, vitrification and nanowarming. Despite several studies demonstrating extended preservation windows, there are several limitations that must be overcome prior to clinical translation. As both machine perfusion and subzero preservation protocols have rapidly advanced in the past few years, special consideration should be given to their potential complementary utilization.

SUMMARY

Current and emerging machine perfusion and preservation technologies in VCA have great promise to transform the field of reconstructive transplantation, as every extra hour of CIT helps ease the complexities of the peri-transplant workflow. Amongst the many advantages, longer preservation windows may allow for elective procedures, improved matching, establishment of novel immunomodulatory protocols and global transport of grafts, ultimately enabling us the ability to offer this life changing procedure to more patients.

Analysis of ethics dumping and proposed solutions in the field of biomedical research in China

As international academic exchanges and cooperation deepen, China has actively engaged in international biomedical research collaboration and achieved significant success. However, these accomplishments have been accompanied by ethical controversies and issues, with ethics dumping being a recurrently discussed focus among scholars. This paper reviews ethics dumping incidents in China's biomedical research field and analyzes the underlying causes to answer why China is often susceptible to ethics dumping. We argue that the primary reasons include weak ethical awareness among some researchers, an oversimplified research evaluation system, gaps in relevant ethics governance and oversight mechanisms, and limited capabilities of certain ethics committees. To address these issues, we propose five ethics governance recommendations: establishing refined ethics committees at various levels and types; advancing theoretical and practical research on science and technology ethics governance; strengthening legislation and regulation related to emerging science and technology; emphasizing self-regulation and capacity building of research institutions; and providing special protection and healthcare for victims of ethics dumping. The aim is to enhance China's research supervision system and prevent similar ethics dumping incidents from recurring.

Heads, Bodies, Brains, and Selves: Personal Identity and the Ethics of Whole-Body Transplantation

Plans to attempt what has been called a head transplant, a body transplant, and a head-to-body transplant in human beings raise numerous ethical, social, and legal questions, including the circumstances, if any, under which it would be ethically permissible to attempt whole-body transplantation (WBT) in human beings, the possible effect of WBT on family relationships, and how families should shape WBT decisions. Our assessment of many of these questions depends partially on how we respond to sometimes centuries-old philosophical thought experiments about personal identity. As with so much in bioethics, it is impossible to escape, or at least inadvisable to try to bypass, the relevant foundational philosophical concerns.

The Ethics of Head Transplant from the Confucian Perspective of Human Virtues

Head transplantation has ignited intense discussions about whether it should be done scientifically and ethically. This paper examines the ethics of head transplantation from a Confucian perspective and offers arguments against the permissibility of head transplantation. From a Confucian point of view, human beings are the most precious organisms in the world, and ren (benevolence) and li (propriety) are the basic moral principles of human beings. As long as head transplant technology remains underdeveloped, this procedure should not be done because it will pose a serious risk of harm to humans and thus violate the principles of Confucian ren and li. If head transplant technology matures to the point that it would be safe to try in humans, it still should not be performed because it would change the selfhood or identity of the head donor and the body donor and create a new person. Confucian personal virtues greatly depend on selfhood or personal identity, and selfhood or personal identity depend on one's body cultivation and mind rectification. Through the hard effort of body cultivation and mind rectification, one transforms one's selfhood or identity and personality. This selfhood, identity, and personality cannot be separated from one's body but are embedded in one's body. Thus, head transplant would destroy two persons' identities and result in a new person, and the characteristics of this new person's identity are still unknown.

Recovery of Brain in Chick Embryos by Growing Second Heart and Brain

To recover chick embryos damaged the brain, two methods are presented. In both of them, somatic cells of an embryo introduced into an egg cell and an embryo have emerged. In one method, injured a part of the brain in the head of an embryo is replaced with a healthy part of the brain. In the second method, the heart of brain embryo dead is transplanted with the embryo heart. In this mechanism, new blood cells are emerged in the bone marrow and transmit information of transplantation to subventricular zone (SVZ) of the brain through the circulatory system. Then, SVZ produces new neural stem cells by a subsequent dividing into neurons. These neurons produce new neural circuits within the brain and recover the injured brain. To examine the model, two hearts of two embryos are connected, and their effects on neural circuits are observed.

First Human Head Transplantation: Surgically Challenging, Ethically Controversial and Historically Tempting – an Experimental Endeavor or a Scientific Landmark?

According to many, head transplantation is considered to be an extraordinary and impossible surgical procedure. However, nowadays, relevant literature and recent advances suggest that the first human head transplantation might be feasible. This innovative surgery promises a life-saving procedure to individuals who suffer from a terminal disease, but whose head and brain are healthy. Recently, the first cephalosomatic anastomosis in a human model was successfully performed, confirming the surgical feasibility of the procedure, but still not the real outcome. Skepticism and several considerations, including surgical, ethical and psychosocial issues, have emerged in the scientific community since this imaginary procedure seems to be more feasible than ever before.

PPARβ/δ: Linking Metabolism to Regeneration

In contrast to the general belief that regeneration is a rare event, mainly occurring in simple organisms, the ability of regeneration is widely distributed in the animal kingdom. Yet, the efficiency and extent of regeneration varies greatly. Humans can recover from blood loss as well as damage to tissues like bone and liver. Yet damage to the heart and brain cannot be reversed, resulting in scaring. Thus, there is a great interest in understanding the molecular mechanisms of naturally occurring regeneration and to apply this knowledge to repair human organs. During regeneration, injury-activated immune cells induce wound healing, extracellular matrix remodeling, migration, dedifferentiation and/or proliferation with subsequent differentiation of somatic or stem cells. An anti-inflammatory response stops the regenerative process, which ends with tissue remodeling to achieve the original functional state. Notably, many of these processes are associated with enhanced glycolysis. Therefore, peroxisome proliferator-activated receptor (PPAR) β/δ—which is known to be involved for example in lipid catabolism, glucose homeostasis, inflammation, survival, proliferation, differentiation, as well as mammalian regeneration of the skin, bone and liver—appears to be a promising target to promote mammalian regeneration. This review summarizes our current knowledge of PPARβ/δ in processes associated with wound healing and regeneration.

The immunologic considerations in human head transplantation

The idea of head transplantation appears at first as unrealistic, unethical, and futile. Here we discuss immunological considerations in human head transplantation. In a separate accompanying article we discuss surgical, ethical, and psychosocial issues concerned in body-to-head transplantation (BHT) [1]. The success of such an unusual allograft, where the donor and the recipient can reject each other, depends on prevention of complex immunologic reactions, especially rejection of the head by the body (graft-vs-host) or probably less likely, the possibility of the head rejecting the total body allograft (host-vs-graft). The technical and immunologic difficulties are enormous, especially since rapid nerve and cord connections and regeneration have not yet been possible to achieve. In this article we begin by briefly reviewing neuro-immunologic issues that may favor BHT such as the blood brain barrier (BBB) and point out its shortcomings. And we touch on the cellular and humoral elements in the brain proper that differ in some respects from those in other organs and in the periphery. Based on recent successes in vascular composite allografts (VCAs), we will elaborate on potential specific advantages and difficulties in BHT of various available immunosuppressive medications already utilized in VCAs. The risk/benefit ratio of these drugs will be emphasized in relation to direct brain toxicity such as seizure disorders, interference, or promotion of nerve regeneration, and potentiation of cerebral viral infections. The final portion of this article will focus on pre-transplant immunologic manipulation of the deceased donor body along with pretreatment of the recipient.