Name der Zeitschrift: Deutsche Zeitschrift für Philosophie Jahrgang: 65 Heft: 2 Seiten: 183-205.

The building of a global model of carcinogenesis is one of modern biology’s greatest challenges. The traditional somatic mutation theory is now supplemented by a new approach, called the Tissue Organization Field Theory. According to TOFT, the original source of cancer is loss of tissue organization rather than genetic mutations. In this paper, we study the argumentative strategy used by the advocates of TOFT to impose their view. In particular, we criticize their claim of incompatibility used to justify the necessity (...) to definitively reject SMT. First, we note that since it is difficult to build a non-ambiguous experimental demonstration of the superiority of TOFT, its partisans add epistemological and metaphysical arguments to the debate. This argumentative strategy allows them to defend the necessity of a paradigm shift, with TOFT superseding SMT. To do so, they introduce a notion of incompatibility, which they actually use as the Kuhnian notion of incommensurability. To justify this so-called incompatibility between the two theories of cancer, they move the debate to a metaphysical ground by assimilating the controversy to a fundamental opposition between reductionism and organicism. We show here that this argumentative strategy is specious, because it does not demonstrate clearly that TOFT is an organicist theory. Since it shares with SMT its vocabulary, its ontology and its methodology, it appears that a claim of incompatibility based on this metaphysical plan is not fully justified in the present state of the debate. We conclude that it is more cogent to argue that the two theories are compatible, both biologically and metaphysically. We propose to consider that TOFT and SMT describe two distinct and compatible causal pathways to carcinogenesis. This view is coherent with the existence of integrative approaches, and suggests that they have a higher epistemic value than the two theories taken separately. (shrink)

This article addresses the physical chemical processes underlying biological self-organisation by which a homogenous solution of reacting chemicals spontaneously self-organises. Theoreticians have predicted that self-organisation can arise from a coupling of reactive processes with molecular diffusion. In addition, the presence of an external field, such as gravity, at a critical moment early in the process may determine the morphology that subsequently develops. The formation, in-vitro, of microtubules, a constituent of the cellular skeleton, shows this type of behaviour. The preparations spontaneously (...) self-organise by reaction-diffusion and the morphology that develops depends upon the presence of gravity at a critical bifurcation time early in the process. Here, we present numerical simulations of a population of microtubules that reproduce this behaviour. Microtubules can grow from one end whilst shrinking from the other. The shrinking end leaves behind a chemical trail of high tubulin concentration. Neighbouring microtubules preferentially grow into these regions, whilst avoiding regions of low tubulin concentration. The chemical trails produced by individual microtubules thus activate and inhibit the formation of neighbouring microtubules and this progressively leads to self-organisation. Gravity acts by way of its directional interaction with the macroscopic density fluctuations present in the solution arising from microtubule disassembly. (shrink)

Microtubules, major elements of the cell skeleton are, most of the time, well organized in vivo, but they can also show self-organizing behaviors in time and/or space in purified solutions in vitro. Theoretical studies and models based on the concepts of collective dynamics in complex systems, reaction–diffusion processes and emergent phenomena were proposed to explain some of these behaviors. In the particular case of microtubule spatial self-organization, it has been advanced that microtubules could behave like ants, self-organizing by ‘talking to (...) each other’ by way of hypothetic concentrated chemical trails of tubulin that are expected to be released by their disassembling ends. Deterministic models based on this idea yielded indeed like-looking spatio-temporal self-organizing behaviors. Nevertheless the question remains of whether microscopic tubulin trails produced by individual or bundles of several microtubules are intense enough to allow microtubule self-organization at a macroscopic level. In the present work, by simulating the diffusion of tubulin in microtubule solutions at the microscopic scale, we measure the shape and intensity of tubulin trails and discuss about the assumption of microtubule self-organization due to the production of chemical trails by disassembling microtubules. We show that the tubulin trails produced by individual microtubules or small microtubule arrays are very weak and not elongated even at very high reactive rates. Although the variations of concentration due to such trails are not significant compared to natural fluctuations of the concentration of tubuline in the chemical environment, the study shows that heterogeneities of biochemical composition can form due to microtubule disassembly. They could become significant when produced by numerous microtubule ends located in the same place. Their possible formation could play a role in certain conditions of reaction. In particular, it gives a mesoscopic basis to explain the collective dynamics observed in excitable microtubule solutions showing the propagation of concentration waves of microtubules at the millimeter scale, although we doubt that individual microtubules or bundles can behave like molecular ants. (shrink)

The genetic code has evolved from its initial non-degenerate wobble version until reaching its present state of degeneracy. By using the stereochemical hypothesis, we revisit the problem of codon assignations to the synonymy classes of amino-acids. We obtain these classes with a simple classifier based on physico-chemical properties of nucleic bases, like hydrophobicity and molecular weight. Then we propose simple RNA ring structures that present, overlap included, one and only one codon by synonymy class as solutions of a combinatory variational (...) problem. We compare these solutions to sequences of present RNAs considered as relics, with a high interspecific invariance, like invariant parts of tRNAs and micro-RNAs. We conclude by emphasizing some optimal properties of the genetic code. (shrink)

This paper is devoted to computer modelling of the development and regeneration of multicellular biological structures. Some species are able to regenerate parts of their body after amputation damage, but the global rules governing cooperative cell behaviour during morphogenesis are not known. Here, we consider a simplified model organism, which consists of tissues formed around special cells that can be interpreted as stem cells. We assume that stem cells communicate with each other by a set of signals, and that the (...) values of these signals depend on the distance between cells. Thus the signal distribution characterizes location of stem cells. If the signal distribution is changed, then the difference between the initial and the current signal distribution affects the behaviour of stem cells—e.g. as a result of an amputation of a part of tissue the signal distribution changes which stimulates stem cells to migrate to new locations, appropriate for regeneration of the proper pattern. Moreover, as stem cells divide and form tissues around them, they control the form and the size of regenerating tissues. This two-level organization of the model organism, with global regulation of stem cells and local regulation of tissues, allows its reproducible development and regeneration. (shrink)

The field of synthetic biology is looking forward engineering framework for safely designing reliable de-novo biological functions. In this undertaking, Computer-Aided-Design environments should play a central role for facilitating the design. Although, CAD environment is widely used to engineer artificial systems the application in synthetic biology is still in its infancy. In this article we address the problem of the design of a high level language which at the core of CAD environment. More specifically the Gubs language is a specification (...) language used to describe the observations of the expected behaviour. The compiler appropriately selects components such that the observation of the synthetic biological function resulting to their assembly complies to the programmed behaviour. (shrink)

Vision substitution by electro-stimulation has been studied since the 60s beginning with P. Bach-y-Rita. Camera pictures or movies encoded in gray levels are displayed using an electro-stimulation display device on the surface of a body part, such as the skin or the tongue. Medical-technical devices have been developed on this principle to compensate for sensory-motor disabilities such as blindness or loss of balance, or to guide specific actions, such as surgery. However, the electrical signals of stationary or moving slowly moving (...) objects, displayed on a Tongue display unit , are quickly lost due to saturation of receptors undergoing electrostimulation. We propose to add random saccades or sparkle to the displayed visual scene to increase the quality of pattern recognition by the subjects. In the present experimental trimodal study , we show that the presence of a moderate sparkle level enhances the perception of the direction of lines drawn on a TDU and reduces the response time. (shrink)

In this article we present a new kind of computing device that uses biochemical reactions networks as building blocks to implement logic gates. The architecture of a computing machine relies on these generic and composable building blocks, computation units, that can be used in multiple instances to perform complex boolean functions. Standard logical operations are implemented by biochemical networks, encapsulated and insulated within synthetic vesicles called protocells. These protocells are capable of exchanging energy and information with each other through transmembrane (...) electron transfer. In the paradigm of computation we propose, protoputing, a machine can solve only one problem and therefore has to be built specifically. Thus, the programming phase in the standard computing paradigm is represented in our approach by the set of assembly instructions that directs the wiring of the protocells that constitute the machine itself. To demonstrate the computing power of protocellular machines, we apply it to solve a NP-complete problem, known to be very demanding in computing power, the 3-SAT problem. We show how to program the assembly of a machine that can verify the satisfiability of a given boolean formula. Then we show how to use the massive parallelism of these machines to verify in less than 20 min all the valuations of the input variables and output a fluorescent signal when the formula is satisfiable or no signal at all otherwise. (shrink)

The Enzymatic control reactions model was presented within the scope of fractional calculus. In order to accommodate the usual initial conditions, the fractional derivative used is in Caputo sense. The methodologies of the three analytical methods were used to derive approximate solution of the fractional nonlinear system of differential equations. Two methods use integral operator and the other one uses just an integral. Numerical results obtained exhibit biological behavior of real world problem.

Large sets of elements interacting locally and producing specific architectures reliably form a category that transcends the usual dividing line between biological and engineered systems. We propose to call them morphogenetically architected complex systems. While taking the emergence of properties seriously, the notion of MACS enables at the same time the design of operational means that allow controlling and even, paradoxically, programming this emergence. To demonstrate our claim, we first show that among all the self-organized systems studied in the field (...) of Artificial Life, the specificity of MACS essentially lies in the close relation between their emergent properties and functional properties. Second, we argue that to be a MACS a system does not need to display more than weak emergent properties. Third, since the notion of weak emergence is based on the possibility of simulation, whether computational or mechanistic via machines, we see MACS as good candidates to help design artificial self-architected systems but also harness and redesign living ones. (shrink)

The classic model of blood pressure regulation by Guyton et al. set a new standard for quantitative exploration of physiological function and led to important new insights, some of which still remain the focus of debate, such as whether the kidney plays the primary role in the genesis of hypertension. Key to the success of this model was the fact that the authors made the computer code freely available and eventually provided a convivial user interface for exploration of model behavior (...) on early microcomputers. Ikeda et al. developed an offshoot of the Guyton model targeting especially the regulation of body fluids and acid–base balance; their model provides extended renal and respiratory functions and would be a good basis for further extensions. In the interest of providing a simple, useable version of Ikeda et al.’s model and to facilitate further such extensions, we present a practical implementation of the model of Ikeda et al., using the ODE solver Berkeley Madonna. (shrink)

Building a meaningful model of biological regulatory network is usually done by specifying the components and their interactions, by guessing the values of parameters, by comparing the predicted behaviors to the observed ones, and by modifying in a trial-error process both architecture and parameters in order to reach an optimal fitness. We propose here a different approach to construct and analyze biological models avoiding the trial-error part, where structure and dynamics are represented as formal constraints. We apply the method to (...) Hopfield-like networks, a formalism often used in both neural and regulatory networks modeling. The aim is to characterize automatically the set of all models consistent with all the available knowledge. The available knowledge is formalized into formal constraints. The latter are compiled into Boolean formula in conjunctive normal form and then submitted to a Boolean satisfiability solver. This approach allows to formulate a wide range of queries, expressed in a high level language, and possibly integrating formalized intuitions. In order to explore its potential, we use it to find cycles for 3-nodes networks and to determine the flower morphogenesis regulatory network of Arabidopsis thaliana. Applications of this technique are numerous and concern the building of models from data as well as the design of biological networks possessing specified behaviors. (shrink)

Various threshold Boolean networks, a formalism used to model different types of biological networks, can produce similar dynamics, i.e. share same behaviors. Among them, some are complex, others not. By computing both structural and behavioral complexities, we show that most TBNs are structurally complex, even those having simple behaviors. For this purpose, we developed a new method to compute the structural complexity of a TBN based on estimates of the sizes of equivalence classes of the threshold Boolean functions composing the (...) TBN. (shrink)

Background. Herpes zoster is a disease that mainly causes severe segmental neuralgia and vesicles after infection with herpes zoster virus. At the same time, more than 9 to 34 percent of patients have postherpetic neuralgia present with chronic pain for months or even years. Moxibustion has been used to treat herpes zoster and postherpetic neuralgia for many years; however, there has been no comprehensive study to evaluate the efficacy and safety of moxibustion in the treatment of herpes zoster and postherpetic (...) neuralgia. More studies evaluated the combined effects of acupuncture and moxibustion. Therefore, the purpose of this systematic review is to evaluate their efficacy and safety, so as to provide an evidence-based basis for the clinical application of moxibustion in the treatment of HZ and PHN. Method. The literature search was conducted in nine Chinese and English databases, and randomized controlled trials were pooled from their inceptions to June 2020. The included literature was screened, and data were extracted. RevMan 5.3 software and Stata software were used for statistical analysis. The primary outcome was the total effect. The secondary outcomes include VAS, NRS, and time of analgesia. Outcomes. From a total of 1957 identified studies, 31 were included in analysis. 31 RCTs contained the experimental sample of 1185 cases and the control sample of 1149 cases reported efficiency of different moxibustions in the treatment of herpes zoster, statistical heterogeneity inspection without heterogeneity. So, we used the fixed-effects model, merge effect quantity OR = 3.89, Z = 8.86, and it suggested sample merger analysis was statistically significant. Also, the moxibustion, compared to other methods in the treatment of herpes zoster and herpes zoster neuralgia efficiency, increased significantly. The VAS scales, WMD = 1.69, and the time of analgesia, WMD = 2.41, indicated that moxibustion surpassed others in the relief of pain. NRS was just reported in one study. It was not statistically significant. There was no significant difference in adverse effects OR = 0.61, Z = 1.56. Conclusion. Moxibustion has obvious advantages over other therapies in the treatment of HZ and PHN. However, due to the obvious publication bias, the interpretation of the results should be cautious, and more rigorous randomized controlled clinical studies should be included to further confirm the results in the future. (shrink)

Herpes simplex virus (HSV)‐derived vectors are currently being developed for the introduction of foreign DNA into neurons. HSV vectors can facilitate a range of molecular studies on postmitotic neurons and may ultimately be used for somatic cell gene therapy for certain neurologic diseases. In this article, the salient features of the pathogenesis and molecular biology of HSV relevant to its use as a vector are described, along with an overview of the methods used to derive these vectors. The accomplishments which (...) have been made to date using the HSV vector system are discussed, with emphasis on the issues of this technology which remain to be addressed. HSV has the potential to be a most useful tool for neuronal cell transgenesis and it is likely that important neurobiological questions will be answered using this vector system. (shrink)

Herpes simplex virus type 2 is the most prevalent sexually transmitted infection in the world, despite the availability of effective anti-viral treatments. A mathematical model to explore the association between gender and HSV-2 treatment adherence is developed. Threshold parameters are determined and stabilities analyzed. Sensitivity analysis of the reproduction number and the numerical simulations suggest that treatment adherence for both females and males are equally important in keeping the reproduction as low as possible. The basic model is then extended to (...) incorporate time-dependent intervention strategies. The Pontryagin’s Maximum Principle is used to characterize the optimal level of the controls, and the resulting optimality system is solved numerically. (shrink)

The ancient practice of metzitzah b'peh, direct oral suction, is still practiced by ultra-Orthodox Jews as part of the religious rite of male newborn circumcision. Between 2000 and 2011, 11 children have died in New York and New Jersey, following infection by herpes simplex virus, presumably from infected practitioners. The City responded by requiring signed parental consent before oral suction, with parents being warned of the dangers of the practice. This essay argues that informed consent is not an appropriate response (...) to this problem. An outright ban would a better response to a practice that is dangerous to children, but might prove unconstitutional under New York State law. (shrink)

Although 80–90% of adults are seropositive for antibodies against the human parvovirus adeno‐associated virus (AAV), infection has not been associated with either symptoms or disease. In cell culture, AAV infection is not productive unless there is a coinfection with a helper virus, either adenovirus or any type of herpes virus; in the absence of a helper virus coinfection the viral genome is integrated into the genome, usually at a specific site on chromosome 19q13.3‐qter. The integrated genome can be activated and (...) rescued by subsequent super infection by a helper virus. The high frequency of site‐specific integration by AAV and the lack of associated disease have encouraged the use of AAV as a vector for gene therapy. This review will focus on the molecular mechanisms involved in the establishment of, and rescue from, the latent state and their relevance to use of AAV as a vector. (shrink)

Some of the causes of the 'sexual revolution' during the past few decades are widely known: The development of relatively safe and reliable contraceptives, especially the birth-control pill; the 'morning after' pill; antibiotics to relieve or cure sexually transmitted diseases such as gonorrhea, herpes, and syphilis; the increased social acceptance of pre-marital sex, homosexuality, and other behaviors that formerly were considered deviant; and the legalization of abortion as the ultimate 'contraceptive'. But little attention has been paid to two rather cerebral (...) factors relevant to these developments – namely, ethical theories, and theories of overpopulation. In this paper I will argue that these two less well-known and more subtle factors have been at least as powerful as the more obvious factors mentioned above, in bringing about sea-changes in sexual mores. More specifically, I will argue that some implicit approaches to ethical theory are more conducive than others to bringing about the present status quo in sexual mores, and that the widespread belief in world overpopulation has not only changed the moral climate regarding sexuality, but has helped to redefine what is moral and what is immoral. (shrink)

Consistent with the complexity of the temporally regulated processes that must occur for growth and development of higher eukaryotes, it is now apparent that transcription is regulated by the formation of multi‐component complexes that assemble on the promoters of genes. These complexes can include (in addition to the five or more general transcription factors and RNA polymerase II) DNA‐binding proteins, transcriptional activators, coactivators, adaptors and various accessory proteins. The best studied example of a complex that includes a transcriptional adaptor, accessory (...) proteins and a DNA‐binding protein is that involving the herpes simplex virus VP16 protein. Evidence suggests that the adenovirus E1a protein and the cellular Sp1 and CTF/NF1 transcription factors also function through adaptors or coactivators. Each additional component of the transcription complex provides the cell with another point at which to exert control of gene expression. (shrink)

INTRODUCTIONIs the non-therapeutic circumcision of infant males morally permissible? The most recent major development in this long-simmering debate was the 2012 release of a policy statement and technical report on circumcision by the American Academy of Pediatrics . In these documents, the US paediatricians’ organisation claimed that the potential health benefits of infant circumcision now outweigh the risks and costs. They went on to suggest that their analysis could be taken to justify the decision of parents to choose circumcision for (...) their incompetent children.1Circumcision and ‘health benefits’The AAP's pronouncement unleashed a firestorm of commentary, much of it censorious. In this issue, human rights attorney J Steven Svoboda and Professor of Clinical Paediatrics Robert Van Howe take the AAP to taski for committing numerous significant errors, both in their analysis of relevant evidence and in basic medical-ethical reasoning.3 In addition, an independent international panel—composed of 38 leading paediatricians, paediatric surgeons, urologists, medical ethicists and heads of hospital boards and children's health societies—has likewise condemned the findings of the AAP. Writing in the journal Pediatrics, these authors state: "Only one of the arguments put forward by the American Academy of Pediatrics has some theoretical relevance in relation to infant male circumcision; namely, the possible protection against urinary tract infections in infant boys, which can easily be treated with antibiotics without tissue loss. The other claimed health benefits, including protection against HIV/AIDS, genital herpes, genital warts, and penile cancer, are questionable, weak, and likely to have little public health relevance in a Western context, and they do not represent compelling reasons for surgery before boys are old enough to decide for themselves.4"My own analysis of the AAP documents—and of ‘health benefits’ defences of circumcision generally—can be found elsewhere.5 Let me turn my attention in this editorial, then, to …. (shrink)

Hume’s response to his very personal encounter with skepticism is well known: “I dine, I play a game of back-gammon, I converse, and am merry with my friends; and when after three or four hour’s amusement, I wou’d return to these speculations, they appear so cold, and strain’d, and ridiculous, that I cannot find it in my heart to enter into them any farther”.1 As many commentators have noted, this “response” to skepticism is deeply unsatisfying. For example, Brian Ribeiro writes, (...) “Having dinner and watching some TV no more ‘cures’ or ‘solves’ the skeptical problem than the drugs given to those with herpes ‘cure’ their... (shrink)

In lieu of an abstract, here is a brief excerpt of the content:_Russell_ journal (home office): E:CPBRRUSSJOURTYPE2402\INDEXISS.242 : 2005-05-19 13:34
ibliographies, rchival nventories, ndexes INDEX TO RUSSELL’S THE IMPACT OF SCIENCE ON SOCIETY R H Summerfields, The Glade Escrick, York  , .. @.. he edition of the richly allusioned The Impact of Science on Society Tindexed here is that of George Allen and Unwin, published in London in . The pagination of Simon and Schuster’s edition (New York, ) is (...) different and spans pages – instead of the first British edition’s –. The very first edition of the book (New York: Columbia U. P., ) contained two paragraphs comparing Catholicism and Communism that were overlooked for the British and all subsequent editions. Russell regarded them as important, and Sir Stanley Unwin wrote him that they would be incorporated in the next printing. The next printing was not until , and the paragraphs were again overlooked. They belong just before the paragraph on page  beginning “Every fanatical creed” in Chapter , “Science and Values”. These paragraphs are not indexed.—Ed. I meet many people who think that the evils of Communism can be combated by Catholicism. This seems to me a dangerous error. What are the evils of Communism as it has developed? First, adherence to a rigid and static system of doctrine, of which part is doubtful and part demonstrably false. Second, persecution as a means of enforcing orthodoxy. Third, a belief that salvation is only to be found within the Church and that the True Faith must be spread throughout the world, by force if necessary. (These are the beliefs of Communists.) Fourth, that the priesthood, which alone has the right to interpret the Scriptures, has enormous power, physical east of the Iron Curtain and spiritual over the faithful in partibus. Fifth, that this power is used to secure an undue share of wealth for the priesthood at the expense of the rest of the population. Sixth, that bigotry, and the hostility that it engenders, is a potent source of war. Every one of these evils was exhibited by the Catholic Church when it had power and would probably be exhibited again if it recovered the position it had in the Middle Ages. It is therefore irrational to suppose that much would be gained if, in the defeat of Communism, Catholicism were enthroned in its place. (Pp. –) russell: the Journal of Bertrand Russell Studies n.s.  (winter –): – The Bertrand Russell Research Centre, McMaster U.  - _Russell_ journal (home office): E:CPBRRUSSJOURTYPE2402\INDEXISS.242 : 2005-05-19 13:34    Abraham  absolute monarchy  Adler, Alfred  adventure, impulse to ,  vs. rashness  aeroplanes  Africa cotton market  North, and Romans  age, average, in West – agriculture effects of  in history of man  integration into larger economy – wasteful of natural resources – see also soil conservation air power and governments  Alexander the Great and superstition  ambassadors, independence of  America see United States anaesthetics  anarchy  Anaxagoras ,  animals, and man  anthropology  apathy  Arab-Israeli conflict – Arabian Nights slaves of lamp in  Arabs and scientific technique  Archimedes , ,  Argentina agriculture  Arians  Aristotle  and causation – movement of heavenly bodies  armed forces and civil authorities  international, as concentration of power ,  perceptions of own/other nations’  in Russia –,  artillery  arts: authors and artists independence of –, –,  ascetic mentality  Asia: population and prosperity  astrology – astronomers Greek  prospects for life on earth  astronomical events indicating disaster  Atlantic Pact  atom bomb , , ,  atomic energy –, ,  Attica, history  Attlee, Clement  Augustine, Saint scientific argument against astrology – Auschwitz  Australia aborigines ,  agriculture  federal government  Austria: war with Prussia  Authority and the Individual (BR)  authority vs. observation –,  autonomy of physical world , – Aztecs and cannibalism  and infanticide  Babylonians and eclipses  Bacon, Francis and witchcraft  bacteriological war  Baltic–White Sea canal  barbarians, and late Roman Empire ,  Barbarossa (Frederick I)  , independence of  Bede, the Venerable on comets  belief(s) on basis of authority, as unscientific – science as determinant  in superstition  uncivilized peoples  benefits of scientific technique – _Russell_ journal (home office): E:CPBRRUSSJOURTYPE2402\INDEXISS.242 : 2005-05-19 13:34 Index to Impact of Science on Society  Bentham , ,  Bergson, Henri  Bible, false statements in  see also individual books of biological conditions of stability (of society) –, – biology technique(s) from – birth control and population , , – birth rate, low ,  Black Death , – Blimps, Col., Romans as  breeding, scientific – Bright, John  Britain, happiness in  British Empire... 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Xenotransplantation is any transplantation, implantation, or infusion of either live cells, tissues, or organs from a nonhuman animal source, or human bodily fluids, cells, tissues, or organs that have had ex vivo contact with live nonhuman animal cells, tissues, or organs into a human recipient. Most scientists agree that clinical xenotransplantation should not be performed in the absence of accompanying public health safeguards The science upon which that consensus is based has been extensively described in the literature. By and large (...) the most compelling reason for public health safeguards is the possible introduction of new infectious agents into the human life cycle as a result of xenotransplantation.The most frequent source of new infectious diseases in human populations is the transfer of agents, such as viruses, bacteria, or prions, from animals to man. Human diseases and infectious agents that are thought to have originated from animals include influenza, rabies, malaria, lassa fever, lyme disease, AIDS, yellow fever, tuberculosis, the human t-cell lymphotropic virus, the herpes B virus, the hantavirus, and even the bubonic and pneumonic plagues. (shrink)

Xenotransplantation is any transplantation, implantation, or infusion of either live cells, tissues, or organs from a nonhuman animal source, or human bodily fluids, cells, tissues, or organs that have had ex vivo contact with live nonhuman animal cells, tissues, or organs into a human recipient. Most scientists agree that clinical xenotransplantation should not be performed in the absence of accompanying public health safeguards The science upon which that consensus is based has been extensively described in the literature. By and large (...) the most compelling reason for public health safeguards is the possible introduction of new infectious agents into the human life cycle as a result of xenotransplantation.The most frequent source of new infectious diseases in human populations is the transfer of agents, such as viruses, bacteria, or prions, from animals to man. Human diseases and infectious agents that are thought to have originated from animals include influenza, rabies, malaria, lassa fever, lyme disease, AIDS, yellow fever, tuberculosis, the human t-cell lymphotropic virus, the herpes B virus, the hantavirus, and even the bubonic and pneumonic plagues. (shrink)