900 resultados para Non-human animals
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This article examines the current legal regime applicable to animal-human combinations under the Assisted Human Reproduction Act (Canada). The Act prohibits as criminal offences the use of non-human reproductive material in humans, the use in humans of human reproductive material previously transplanted into a non-human life form, the creation of chimeras made from human embryos, and the creation for reproductive purposes of human/non-human hybrids. Additional animal-human combinations, such as transgenic life forms, may be regulated pursuant to section 11 of the Act in the future. The underlying concerns of the Act in establishing this regime appear to be the protection of human health and safety, human dignity and individuality, and the human genome. The Act seems calibrated to prohibit the creation of animal-human combinations that are currently unsafe and scientifically and ethically problematic, while leaving open the possibility of regulating other such combinations with more immediate scientific potential, although these also raise ethical questions. Currently, certain differences subsist in Canada between what is permissible for researchers and institutions funded by federal agencies and those in privately funded research. The development of the regulatory framework under the Act will reveal how freedom of research will be balanced against the need for scientifically valid and ethically justifiable research, and whether these differences will continue to apply.
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Historiquement, les animaux sauvages ont toujours représenté une ressource pour les hommes, assurant la sécurité alimentaire des sociétés locales et traditionnelles. L’exploitation touristique de la faune implique dès lors une évolution dans les modes de vie, la culture et les identités locales. L’objectif de cette recherche doctorale est d’analyser le récréotourisme faunique. Les activités récréotouristiques autour de la faune sauvage traduisent une requalification de la ressource faune, ce qui a des impacts à la fois sur les espaces humains et non humains, les jeux de construction territoriale et sur les rapports développés à la faune sauvage. Ce travail analyse les rapports que les sociétés entretiennent avec la faune sauvage à travers les activités récréotouristiques de chasse et de vision. Ces deux formes de tourisme sont généralement opposées car le tourisme de vision est présenté comme un usage non-consomptif de la ressource alors que le tourisme de chasse est reconnu comme un usage consomptif de la ressource. Dépassant certaines idées reçues sur les pratiques de la chasse et une approche manichéenne entre ces différentes activités, il convient d’interroger les distinctions et / ou le rapport dialogique entre ces pratiques. Afin de conduire cette recherche, le choix d’une analyse comparative a été retenu, laquelle se propose de mettre en perspective différentes études de cas en France et au Canada. Ce travail comparatif permet de mieux comprendre les enjeux touristiques et territoriaux associés à la gestion de la faune sauvage et de penser la transférabilité des processus observés entre différents terrains d’études. D’un point de vue méthodologique, ce travail doctoral nous a conduite à définir un cadre analytique organisé autour de quatre entrées croisant des (i) aspects conceptuels, (ii) l’analyse d’archives, (iii) des méthodes d’observation ainsi que (iv) des outils d’analyse des rapports homme / faune via l’analyse de discours des populations touristiques. La première partie de ce travail présente le contexte théorique de l’étude et la démarche systémique de cette recherche (chapitre 1, 2 et 3). En termes de résultat, ces présupposés méthodologiques et théoriques nous ont permis d’analyser comment les dynamiques du récréotourisme faunique agissent, réagissent et rétroagissent sur l’ensemble du système territorial. Ainsi, la deuxième partie interroge l’organisation socio-spatiale des activités récréotouristiques de chasse et de vision (chapitre 4 et 5). Ces différentes formes de tourisme sont analysées en prenant en compte l’implantation de ces activités au sein des territoires, les attentes touristiques de la part des visiteurs, et les effets des différentes pratiques sur les populations fauniques. La troisième et dernière partie s’intéresse à l’évolution des rapports hommes / faune sauvage dans le temps et l’espace au regard des activités récréotouristiques développées. Le chapitre 6 s’intéresse aux rapports dialectiques entre processus de patrimonialisation et les usages acceptés ou non de la ressource faunique, alors que le chapitre 7 propose une réflexion sur les rapports hommes / animaux à l’échelle de l’individu en interrogeant l’éthique de chacun dans ses usages, ses comportements et ses pratiques développés autour de la faune sauvage.
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Le non-humain et son ontologie sont définis dans ce mémoire en fonction des écrits de Philippe Descola et d’Eduardo Viveiros de Castro, deux figures-clés en anthropologie contemporaine sur l’Amazonie. L’animisme de Descola prête aux non-humains une intériorité humaine et les différencie par leur corps. Le perspectivisme de Viveiros de Castro, quant à lui, suppose que les points de vue différents créent des mondes et établissent ce qui est humain ou non. L’humain correspond au sujet cosmologique à la position pronominale de la première personne du singulier, ou « I », au sein d’une relation. De la sorte, un non-humain se perçoit comme un humain à cette position pronominale « I » et voit l’Autre à la position pronominale « it », position du non-humain. Dans ces deux ontologies, le non-humain est conçu comme une personne capable d’agir dans les mondes. La diversité des êtres inclus dans cette ontologie relationnelle est démontrée par des illustrations provenant de l’ethnographie achuar et araweté de ces deux auteurs. Puis, les relations de parenté, d’alliance et de prédation que les non-humains tissent entre eux et avec les humains exposent l’homologie des rapports non-humains avec les rapports humains. Finalement, l’analyse des méthodes de communication entre le non-humain et l’humain élucide comment la reconnaissance du non-humain dans une communication permet le traitement de ces êtres en tant qu’humains. Le non-humain ne serait donc pas un sujet permanent, mais temporaire le moment de l’interaction.
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L’amyloïdose, une maladie progressive et incurable, implique une vaste panoplie de pathologies et de pathogénèses, qui est expliquée par la grande variabilité biologique et structurale des protéines responsables de la formation des dépôts d’amyloïde. L’amyline (polypeptide amyloïde des îlots pancréatiques, IAPP) est une protéine très susceptible de subir des changements de conformation impliquant les feuillets bêta et conférant aussi des propriétés physicochimiques distinctes. Cette protéine prend alors une forme fibrillaire et se dépose dans les îlots de Langerhans chez les humains atteints de diabète de type 2 ou d’insulinome. Ces dépôts d’amyloïde pancréatique (AIAPP) ont été décrits chez certaines espèces animales telles que les félins domestiques, les grands félins, le raton laveur et les primates non humains. La formation de dépôts d’amyloïde contribue à la pathogénèse du diabète de type 2, mais les mécanismes qui induisent la conversion de l’amyline (IAPP) en amyloïde (AIAPP) ne sont pas complètement compris. Les hypothèses du projet sont que certaines variations présentes dans les séquences peptidiques de l’IAPP provenant de différentes espèces animales jouent un rôle critique pour la formation de fibrilles et que plusieurs composés chimiques aromatiques/phénoliques sont capables d’abroger la formation de dépôts d’amyloïde. Le projet de recherche consiste donc à caractériser la propension des différentes isoformes animales d’IAPP à former de l’amyloïde in vitro afin d’identifier les acides aminés jouant un rôle clé dans cette transformation structurale et ultimement d’inhiber la formation d’amyloïde pancréatique. Le projet se divise en deux volets principaux. Le premier consiste à identifier les différentes séquences peptidiques de l’IAPP retrouvées chez les espèces animales. L’objectif est d’identifier les acides aminés jouant un rôle clé dans la formation d’amyloïde. Le gène de l’IAPP a été séquencé chez plus d’une quarantaine d’espèces. Le potentiel d’agrégation des séquences obtenues a été simulé à l’aide d’outils bioinformatique. Une librairie de 23 peptides a été commandée afin de procéder à des analyses physicochimiques in vitro permettant d’évaluer le potentiel amyloïdogénique (test fluorimétrique à la thioflavine T, essai de liaison au rouge Congo, dichroïsme circulaire, microscopie électronique à transmission) et cytotoxique (sur une lignée cellulaire provenant d’insulinome : INS-1). Les analyses effectuées à partir de la librairie constituée de 23 peptides ont permis d’identifier trois séquences ne formant pas d’amyloïde et qui proviennent des espèces animales suivantes : le tamarin lion doré (Leontopithecus rosalia), le grand dauphin (Tursiops truncatus) et l’alpaga (Vicugna pacos). Un site potentiellement critique est le segment 8-20 présentant le motif NFLVH qui ne forme plus d’amyloïde lorsqu’il est remplacé par le motif DFLGR ou KFLIR. Les acides aminés 29P, 14K et 18R sont également impliqués dans l’inhibition de la transformation structurale en fibrille. La dernière partie du projet consiste à inhiber la formation de l’amyloïde en utilisant des composés chimiques commercialisés (hypoglycémiants, anti-inflammatoires non stéroïdiens) ou nouvellement synthétisés dans notre laboratoire (les aryles éthyles urées). Un criblage d’une soixantaine de composés chimiques a été conduit dans cette étude. Leur efficacité a été testée sur l’IAPP humaine, qui possède un fort potentiel amyloïdogénique. Les techniques utilisées sont les mêmes que celles exploitées précédemment. L’essai de liaison croisée photo-induite ("photo-induced cross-linking of unmodified proteins", PICUP) a été réalisé afin d’étudier les formes intermédiaires (monomères, oligomères). Un total de 11 composés chimiques a démontré un potentiel à inhiber l’agrégation des fibrilles. Pour la classe des hypoglycémiants, le glyburide, le répaglinide et la troglitazone ont montré l’activité thérapeutique la plus élevée pour retarder et réduire la formation de fibrilles. Les anti-inflammatoires antiamyloïdogènes actifs incluaient le diclofenac, le méloxicam, le phénylbutazone, le sulindac et le ténoxicam. Les aryles étyles urées les plus intéressantes étaient la EU-362 et la EU-418. Tous ces composés ont conféré une protection cellulaire contre l’activité cytotoxique des fibrilles. Les molécules actives possèdent des éléments structuraux communs tels des substituants donneurs d’électrons (alcool, amine, halogène) sur un noyau benzène. En conclusion, ce projet de recherche a permis de caractériser l’IAPP chez diverses espèces animales, dont plusieurs chez lesquelles elle n’avait pas encore été décrite, de déterminer les sites jouant un rôle clé dans sa transformation en amyloïde et, ultimement, de tester le potentiel thérapeutique de nouveaux agents antiamyloïdogènes dans le diabète de type 2. Nous espérons que ce projet ouvrira ainsi la porte à de nouvelles stratégies de traitement.
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Since megakaryocytes are the cellular precursors of platelets we have investigated whether they share responses to platelet agonists, in particular collagen. Although previous studies have reported responses to thrombin in non-human megakaryocytes, through studies of single cell calcium responses and protein tyrosine-phosphorylation we demonstrate for the first time that both isolated human megakaryocytes and CD41/61-positive megakaryocytes derived in culture from CD34+ cells share responses to the platelet agonists collagen, collagen-related peptide and thrombin. The responses to either collagen or CRP were seen only in the most mature megakaryocytes and not in megakaryocyte-like cell lines, suggesting that the response to collagen is a characteristic developed late during megakaryocyte differentiation. These primary cells offer the opportunity to use many molecular and cellular techniques to study and manipulate signalling events in response to platelet receptor agonists, which cannot be performed in the small, anucleate platelet itself.
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Community resilience is widely understood as a critical element in the relatively under-explored concept of social resilience. Through engaging with ‘more-than-human’ literatures, a more expansive view of the ‘social’ emerges, which repositions individuals as networked and agency as relational. This moves resilience away from its hegemonic positioning as a neoliberal strategy of individualisation and responsibilisation, with it instead emerging as an everyday ‘doing’ embedded in the human and non-human networks of relationality that we form and are formed by. The paper develops this socio-cultural conceptualisation through an original and empirically grounded discussion of Finnish farm communities and the role of the forest in developing, maintaining and enhancing these essential, connective assemblages. Resilience becomes conceptualised as dynamic, uneven, multiple and contextual performances or resiliences. While this further problematizes the comparative measurement and operationalisation of resilience, its networked and relational nature arguably offers a more inclusive and ethically grounded concept that, furthermore, negates the socio-ecological divide that persists in resilience thinking.
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The human malaria parasite Plasmodium vivax is responsible for 25 - 40% of the similar to 515 million annual cases of malaria worldwide. Although seldom fatal, the parasite elicits severe and incapacitating clinical symptoms and often causes relapses months after a primary infection has cleared. Despite its importance as a major human pathogen, P. vivax is little studied because it cannot be propagated continuously in the laboratory except in non- human primates. We sequenced the genome of P. vivax to shed light on its distinctive biological features, and as a means to drive development of new drugs and vaccines. Here we describe the synteny and isochore structure of P. vivax chromosomes, and show that the parasite resembles other malaria parasites in gene content and metabolic potential, but possesses novel gene families and potential alternative invasion pathways not recognized previously. Completion of the P. vivax genome provides the scientific community with a valuable resource that can be used to advance investigation into this neglected species.
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Parasites of wild primates are important for conservation biology and human health due to their high potential to infect humans. In the Amazon region, non-human primates are commonly infected by Trypanosoma cruzi and T rangeli, which are also infective to man and several mammals. This is the first survey of trypanosomiasis in a critically endangered species of tamarin, Saguinus bicolor (Callitrichidae), from the Brazilian Amazon Rainforest. Of the 96 free-ranging specimens of S. bicolor examined 45 (46.8%) yielded blood smears positive for trypanosomes. T rangeli was detected in blood smears of 38 monkeys (39.6%) whereas T. cruzi was never detected. Seven animals (7.3%) presented trypanosomes of the subgenus Megatrypanum. Hemocultures detected 84 positive tamarins (87.5%). Seventy-two of 84 (85.7%) were morphologically diagnosed as T rangeli and 3 (3.1%) as T. cruzi. Nine tamarins (9.4%) yielded mixed cultures of these two species, which after successive passages generated six cultures exclusively of T. cruzi and two of T rangeli, with only one culture remaining mixed. Of the 72 cultures positive for T rangeli, 62 remained as established cultures and were genotyped: 8 were assigned to phylogenetic lineage A (12.9%) and 54 to lineage B (87.1%). Ten established cultures of T. cruzi were genotyped as TCI lineage (100%). Transmission of both trypanosome species, their potential risk to this endangered species and the role of wild primates as reservoirs for trypanosomes infective to humans are discussed. (C) 2008 Elsevier B.V. All rights reserved.
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Taking Sweden into the future – Bio-objectification of new medical technology In this article, we analyze how contemporary discursive silences around new biotechnologies such as cybrids and induced pluripotent stem cells (iPSC), have been enabled by earlier policy processes in the area, e.g. boundary work around what is human and non-human, living and non-living, subject and object. The analysis of policy processes around xenotransplantations and the use of human embryonic stem cells, shows that the stem cells’ and xenografts’ “bio-identities” become stabilized through high expectations for the future, a lack of therapeutic possibilities and struggles over definitions of life. The policy processes around human embryonic stem cells and organs from other animals, are characterized by a normalization of certain understandings of ”life”, trust in scientific progress and it’s national financial potentials and a categorization of criticism as irrational. Through these “bio-objectification processes”, debate and decision making has been moved from a political and public context into ethical committees and research funding bodies. The article concludes by discussing consequences of this political non-handling of biomedical technologies and how these bioobjects could be re-politicized.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The use of non-human primates in scientific research has contributed significantly to the biomedical area and, in the case of Callithrix jacchus, has provided important evidence on physiological mechanisms that help explain its biology, making the species a valuable experimental model in different pathologies. However, raising non-human primates in captivity for long periods of time is accompanied by behavioral disorders and chronic diseases, as well as progressive weight loss in most of the animals. The Primatology Center of the Universidade Federal do Rio Grande do Norte (UFRN) has housed a colony of C. jacchus for nearly 30 years and during this period these animals have been weighed systematically to detect possible alterations in their clinical conditions. This procedure has generated a volume of data on the weight of animals at different age ranges. These data are of great importance in the study of this variable from different perspectives. Accordingly, this paper presents three studies using weight data collected over 15 years (1985-2000) as a way of verifying the health status and development of the animals. The first study produced the first article, which describes the histopathological findings of animals with probable diagnosis of permanent wasting marmoset syndrome (WMS). All the animals were carriers of trematode parasites (Platynosomum spp) and had obstruction in the hepatobiliary system; it is suggested that this agent is one of the etiological factors of the syndrome. In the second article, the analysis focused on comparing environmental profile and cortisol levels between the animals with normal weight curve evolution and those with WMS. We observed a marked decrease in locomotion, increased use of lower cage extracts and hypocortisolemia. The latter is likely associated to an adaptation of the mechanisms that make up the hypothalamus-hypophysis-adrenal axis, as observed in other mammals under conditions of chronic malnutrition. Finally, in the third study, the animals with weight alterations were excluded from the sample and, using computational tools (K-means and SOM) in a non-supervised way, we suggest found new ontogenetic development classes for C. jacchus. These were redimensioned from five to eight classes: infant I, infant II, infant III, juvenile I, juvenile II, sub-adult, young adult and elderly adult, in order to provide a more suitable classification for more detailed studies that require better control over the animal development
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The circadian system consists of multiple oscillators organized hierarchically, with the suprachiasmatic nucleus (SCN) as the master oscillator to mammalians. There are lots of evidences that each SCN cell is an oscillator and that entrainment depends upon coupling degree between them. Knowledge of the mechanism of coupling between the SCN cells is essential for understanding entrainment and expression of circadian rhythms, and thus promote the development of new treatments for circadian rhythmicity disorders, which may cause various diseases. Some authors suggest that the dissociation model of circadian rhythm activity of rats under T22, period near the limit of synchronization, is a good model to induce internal desynchronization, and in this way, enhance knowledge about the coupling mechanism. So, in order to evaluate the pattern of the motor activity circadian rhythm of marmosets, Callithrix jacchus, in light-dark cycles at the lower limit of entrainment, two experiments were conducted: 1) 6 adult females were submitted to the LD symmetric cycles T21, T22 and T21.5 for 60, 35 and 48 days, respectively; 2) 4 male and 4 female adults were subjected to T21 for 24 days followed by 18 days of LL, and then back to T21 for 24 days followed by 14 days of LL. Vocalizations of all animals and motor activity of each one of them were continuously recorded throughout the experiments, but the vocalizations were recorded only in Experiment 1. Under the Ts shorter than 24 h, two simultaneous circadian components appeared in motor activity, one with the same period of LD cycle, named light-entrained component, and the other in free-running, named non-light-entrained component. Both components were displayed for all the animals in T21, five animals (83.3%) in T21.5 and two animals (33.3%) in T22. For vocalizations both components were observed under the three Ts. Due to the different characteristics of these components we suggest that dissociation is result of partial synchronization to the LD cycle, wherein at least one group oscillator is synchronized to the LD by relative coordination and masking processes, while at least another group of oscillators is in free-running, but also under the influence of masking by the LD. As the T21 h was the only cycle able to promote the emergence of both circadian components in circadian rhythms of all Callithrix jacchus, this was then considered the lower entrainment limit of LD cycle promoter of dissociation in circadian rhythmicity of this species, and then suggested as a non-human primate model for forced desynchronization
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The circadian timing system (CTS) is responsible for the generation and synchronization and the suprachiasmatic nucleus (SCN) of the hypothalamus has been described as the major circadian pacemaker in many mammalian species. The internal temporal organization managed by SCN is disturbed with aging bringing many pathological disorders that range from loss of complex cognitive performance to simple physiological functions. Therefore, our aim was perform a comparative study of the morphological aspects and neurochemical composition in the SCN of marmosets (Callithrix jacchus) adults and older using immunohistochemical techniques. We found morphometric and neurochemical changes in th SCN o folder animals in comparison to adults, among these a possible decreased in retinal projection to the SCN of older animals, found through a decline in CTB immunostaining, which can occur due atrophy and/or decreasing of fibers from the retinohypothalamic tract (RHT). The Klüver-Barrera histological technique strongly suggests a decrease in those fibers from RHT. Also, by means of a morphometric study, it is found a atrophy and numerical decline of neurons in SCN of aged animals, investigated by Nissl technique, and immunostaining with NeuN and calbindin. Relative optical density (ROD) analysis were used to evaluate the expression of some neurochemical components in SCN, such as GFAP expression, which was increased in older, result that indirectly reinforces that morphological changes occurs due the aging; the vasoactive intestinal polipeptide (VIP) showed no expression alteration in SCN of older animals; the serotonin (5-HT) was descreased in the dorsomedial portion of the SCN, and neurpeptide Y (NPY) apparently also decrease due to the increase of age. Many of these modifications were seen in other animals, such as rodents, human primates and non-human primates. These data about marmoset comes to add new information of the effect of aging on structures responsibles for the circadian rhytmicity, and that some behavioral changes controlled by th SCN, and founded in aged animals, may be caused by these morphological and neurochemical changes. Although some results have been quantitatively negative, qualitatively all analysis show significant change comparing adult and older animals, perhaps due to a low sampling number. In conclusion, the marmoset presents several morphological and neurochemical changes in the SCN of aged animals compared to adults, which may result in behavioral changes that favor pathology aging related
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Objective: the aim of this in vivo study was to evaluate the response of the pulp-dentin complex following application of resin-modified glass-ionomer cement, calcium hydroxide hard-setting cement and EDTA-soluble preparation of dentine matrix proteins (ESDP) in deep cavities prepared in non-human primate teeth. Methods: Eighteen deep Class V buccal cavities were prepared in premolars of four capuccin monkeys. In Groups 1 and 2, the cavity floor was lined with ESDP or a resin-modified glass-ionomer cement (Vitrebond - 3M ESPE), respectively. In Group 3 (control), the cavity was lined with a hard setting calcium hydroxide cement (Dycal - Dentsply). The cavities were subsequently filled with amalgam. After 6 months, the animals were sacrificed and the teeth were prepared for microscopic assessment. Six-micron thick serial sections were stained with H/E, Masson's trichrome and Brown & Brenn techniques. Results: No inflammatory pulpal response was observed for all experimental and control Groups. However, the amount of reactionary dentin deposition differed between groups in the rank order ESDP (Group 1) > calcium hydroxide (Group 3) > resin-modified glass-ionomer (Group 2). These differences were statistically significant. Conclusions: All materials were biocompatible when applied in deep cavities. ESDP stimulated higher deposition of reactionary dentin matrix than Vitrebond and Dycal.