La coqueluche est une pathologie due à la bactérie Bordetella pertussis qui touche les voies respiratoires des patients infectés causant toux, leucocytose, fièvre, et dont les symptômes peuvent aller jusqu’au décès chez les individus les plus à risque (nouveau-nés et enfants immunodéprimés en particulier). Ciblée par différents programmes vaccinaux depuis de nombreuses années, cette pathologie sévit à nouveau dans de nombreux pays développés où le nombre de cas augmente fortement depuis la fin des années 2000. Cette résurgence montre la nécessité de développer de nouvelles stratégies afin de comprendre les mécanismes de l’infection par B. pertussis. Dans ce contexte, la recherche préclinique apparaît comme essentielle pour comprendre la physiopathologie de la coqueluche. De nombreux modèles animaux ont été décrits pour l’étude de la coqueluche mais aucun de ces modèles ne permet de reproduire l’ensemble du spectre des symptômes cliniques de la pathologie, notamment la toux. Cependant, au cours des dernières années un modèle d’infection par Bordetella pertussis chez le jeune babouin a été développé aux Etats-Unis et permet de reproduire la pathologie observée chez l’homme, notamment concernant la toux et la transmission. Ce modèle semble ainsi très prometteur pour l’étude de la physiopathologie de la coqueluche.Cependant, de nombreuses inconnues subsistent dans ce modèle, notamment concernant la colonisation bactérienne et les interactions entre la bactérie et l’hôte. Nous avons ainsi cherché dans cette étude à évaluer d’une part l’impact de différents facteurs comme l’âge des animaux, la dose d’infection ainsi que la voie d’exposition sur la pathologie déclarée par les babouins suite à l’infection par la souche B1917 de B. pertussis afin de pouvoir proposer un parallèle avec les données cliniques disponibles. Nous avons également développé l’utilisation de techniques d’imagerie in vivo comme l’endomicroscopie confocale couplée à la bronchoscopie afin d’étudier la localisation et la cinétique de colonisation et certaines interactions du pathogène dans le tractus respiratoire inférieur au cours de la pathologie. Cette étude nous a ainsi permis d’approfondir les connaissances de physiopathologie de la coqueluche dans ce modèle babouin et consolidera cet outil précieux pour l’évaluation des futures stratégies de prévention contre cette pathologie. / Whooping cough, or pertussis, is a respiratory disease caused by Bordetella pertussis bacterial colonization of human airways. Main symptoms are cough, leukocytosis, fever and may even be lethal for some patients (e.g. newborn infants and immuno-deficient patients). Despite a good vaccination coverage worldwide against pertussis, whooping cough cases have been re-increasing in several developed countries in the past twenty years. This resurgence points out the crucial need to develop new control strategies and to better understand pertussis pathophysiology, notably using appropriate animal models. Numerous preclinical models including mice, rats, rabbits and swine have been described for B. pertussis infection studies. However, none of these models reproduce the full spectrum of clinical pertussis symptoms, especially cough. The recent baboon model of whooping cough described in the last few years in the US appears to be a very relevant model for pertussis pathophysiology studies as these animals reproduced all clinical symptoms as observed in humans including cough.However, many aspects of bacterial colonization and interactions with the host have yet to be described in this model.We have then evaluated diverse parameters such as animal age, the inoculum dose and the exposition route on the pathology symptoms and immune responses developed by baboons following B. pertussis B1917 strain inoculation in order to draw a parallel with human clinical data. We also developed in this model in vivo imaging techniques like confocal endomicroscopy coupled with bronchoscopy in order to evaluate bacterial colonization kinetics, localization and some interactions in the lower respiratory tract of infected baboons. Then, this study brought additional data on whooping cough physiopathology in this baboon model, which will be crucial for evaluating future prevention strategies against pertussis disease

No description available.

<p>Smooth pursuit eye movements are movements of the eyes that are used to foveate moving objects. Their precision and adaptation is believed to depend on a constellation of sites across the cerebellum, but only one region’s contribution is well characterized, the floccular complex. Here, I characterize the response properties of neurons in the oculomotor vermis, another major division of the oculomotor cerebellum whose role in pursuit remains unknown. I recorded Purkinje cells, the output neurons of this region, in two monkeys as they executed pursuit eye movements in response to step ramp target motion. The responses of these Purkinje cells in the oculomotor vermis were very different from responses that have been documented in the floccular complex. The simple spikes of these cells encoded movement direction in retinal, as opposed to muscle coordinates. They were less related to movement kinematics, and had smaller values of trial-by-trial correlations with pursuit speed, latency, and direction than their floccular complex counterparts. Unlike Purkinje cells in the floccular complex, simple spike firing rates in the oculomotor vermis remained unchanged over the course of pursuit adaptation, likely excluding the oculomotor vermis as a site of directional plasticity. Complex spikes of these Purkinje cells were only partially responsive to target motion, and did not fall into any clear opponent directional organization with simple spikes, as has been found in the floccular complex. In general, Purkinje cells in the oculomotor vermis were responsive to both pursuit and to saccadic eye movements, but maintained tuning for the direction of these movements along separate directions at a population level. Predictions of caudal fastigial nucleus activity, generated on the basis of our population of oculomotor vermal Purkinje cells, faithfully tracked moment-by-movement changes in pursuit kinematics. By contrast, these responses did not faithfully track moment-by-moments changes in saccade kinematics. These results suggest that the oculomotor vermis is likely to play a smaller role in influencing pursuit eye movements by comparison to the floccular complex.</p> / Dissertation

Orientador: Sheila Canevese Rahal / Resumo: O objetivo do presente estudo foi avaliar radiograficamente os membros torácicos e pélvicos de um grupo de saguis mantidos em cativeiro, oriundos de apreensões realizadas para o combate do tráfico ilegal de animais. Foram utilizados 14 saguis, sendo 12 adultos e dois juvenis, oito machos e seis fêmeas, com massa corpórea entre 248 e 354 gramas, sendo um sagui-de-tufo-branco (Callithrix jacchus), oito saguis-de-tufo preto (Callithrix penicillata) e cinco saguis híbridos (Callithrix sp.). Com exceção de três saguis que estavam radiograficamente normais, todos os demais apresentaram alterações radiográficas dos membros, pélvicos e/ou torácicos. A despeito das alterações, a maioria dos animais conseguia se locomover sem grandes limitações no cativeiro. Dos 11 saguis com alterações no membro pélvico, cinco (45,45%) apresentavam estreitamento pélvico e desvio varo bilateral do fêmur, sendo um sugestivo de raquitismo e um de osteomalácia. Os demais apresentaram alterações, tais como má-consolidação de fratura acetabular com osteoartrite da cabeça femoral, amputação parcial de membro, antecurvato de ambas as tíbias, osteoartrite do joelho, entre outros. Seis saguis (54,54 %) mostraram alteração no membro torácico, tais como fratura do rádio, subluxação escápulo-umeral e incongruência da articulação úmero-radio-ulnar, entre outros. Foi possível concluir que 78,57% dos saguis avaliados tinham alterações ósseas e/ou articulares detectadas radiograficamente, que foram predominantes nos m... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to provide a radiographic evaluation of the fore- and hind limbs of marmosets in captivity, originated from capture carried out to combat illegal wildlife trade. A total of 14 marmosets, 12 adults and two juveniles, eight males and six females, weighing between 248 and 354 grams were used, including one common marmoset (Callithrix jacchus), eight black-pencilled marmoset (Callithrix penicillata) and five hybrid marmosets (Callithrix sp.). Except three marmosets radiographically normal, all the others showed radiographic changes of the forelimbs and/or hind limbs. Despite the changes, most primates were capable of moving without major limitations in captivity. Of the 11 marmosets with radiographic changes of the hind limbs, five (45.45%) had pelvic narrowing and bilateral varus deviation of the femur, which had one suggestive of rickets and one of osteomalacia. The other marmosets had changes such as malunion of acetabular fracture with hip osteoarthritis, transtíbial amputation, antecurvatum of both tibias, and knee osteoarthritis, among others. Six marmosets (54.54%) showed alterations in the forelimbs, such as radius fracture, scapulohumeral subluxation, and bilateral humeral-radio-ulnar joint incongruence, among others. In conclusion, 78.57% of the evaluated marmosets had bone and/or joint changes detected by plain radiograph, which were found predominantly in the hind limbs and without impediment to locomotion in captivity. / Mestre

Doctor of Philosophy (PhD) / Background: The development of the blood supply in the primate retina has been extensively studied; however the relationship of the differentiating retina to the choroidal blood supply is less well known. The interaction of astrocytes and vascular endothelial cells promotes the development of the retinal vasculature from 14 weeks’ gestation (WG). Initially, astrocytes lead the developing capillaries from the optic nerve towards the macular area. However, neither astrocytes nor endothelial cells enter a prescribed avascular area, within which the fovea later forms. This may be attributed to expression of a factor that inhibits astrocyte and endothelial cell proliferation in the fovea. A factor found in the CNS that is already known to have these effects is transforming growth factor-β (TGF-β). Aims: This thesis investigated the relationship between retinal maturation and choroidal blood vessel supply and the possible role for TGF-β as an antiangiogenic factor in maintaining an avascular fovea during primate retinal development. Methods: Human eyes between 11 WG and 40 years were obtained with ethical approval from Prince of Wales Hospital and the NSW Lions Eye Bank and fixed and sectioned for histological procedures or prepared for polymerase chain reaction (PCR). Macaque eyes from foetal day (fd) 64 to postnatal 11years (p11y) were obtained from Bogor Agriculture University, Indonesia with the approval of the Ethics Committee of the University of Washington, Seattle, USA. Macaque eyes were also fixed and sectioned for immunohistochemistry and in situ hybridisation. RNA was extracted from human foetal retinas and used for RTPCR (Reverse Transcriptase PCR), QPCR (Quantitative PCR) and preparation of riboprobes. PCR products were analysed using both restriction digest and sequencing. RTPCR was used to identify TGF-β1, TGF-β2 and TGF-β3 in the developing human and in the developing and adult macaque retinas whilst QPCR was used to quantify the TGF-β isoforms in central compared to peripheral retina and in foetal compared to adult retina. In situ hybridisation was performed according to a standard protocol and visualised using Roche HNPP Fast Red detection set with designed riboprobes for TGF-β1, TGF-β2 and TGF-β3 (DIG RNA labelling kit). Some sections were counterstained with vimentin antibody. Immunohistochemistry was performed on human retina and choroid sections using antibodies to CD34 and Ki67 and on human and macaque retina using antibodies to synaptophysin, vimentin, GFAP, calbindin, S-opsin, RG-opsin, rhodopsin, TGF-β1, TGF-β2, TGF-β3 and their receptors TβRI and TβRII. Sections of the retina were imaged and analysed using either a Leica Confocal microscope and TCSNT software or Zeiss Confocal microscope and LSM 5 Pascal software. Data from the human retina and choroid sections corresponding to different regions (foveal, parafoveal nasal, parafoveal temporal, nasal and temporal) was collected to measure the number of Ki-67 immunolabelled mitotic endothelial cells and the area of CD34 immunolabelled choriocapillaris using Adobe Photoshop version 5.0.2, NIH software version 1.62 (measurement macros) and Excel. In the human and macaque sections the intensity of TGF-β protein and mRNA expression was captured from different regions of the retina (foveal, parafoveal nasal, parafoveal temporal, nasal, temporal, nasal to disc) to compile montages. Montages were then re-imported into LSM 5 Pascal software to measure the optical density across each montage along the ganglion cell layer, outer neuroblastic zone and photoreceptor layer collecting data in Excel for graphical representation. In addition to the montages, individual sections were assessed for co-localisation of TGF-β and TβR to various retinal cell types. Results: Analyses of choriocapillaris area and endothelial cell (EC) proliferation were able to demonstrate that the area of choriocapillaris endothelium is greater in the foveal region at all ages (14-18.5WG), that the rate of choriocapillaris EC proliferation declines dramatically over this same period and that the lowest rates of EC proliferation are at the incipient fovea. Most importantly these findings indicate that EC proliferation in the choriocapillaris does not appear to be promoted by increased metabolic activity in central retinal neurons which are more developed with higher oxygen and nutrient demands, which is the mechanism widely thought to regulate development of the retinal vasculature. PCR showed all TGF-β isoforms to be present in the human developing and adult retina. QPCR revealed that TGF-β2 was the most predominant isoform, followed by TGF-β3 with very small amounts of TGF-β1 seen. The isoforms were more abundant in developing rather than adult retina and in central rather than peripheral retina. Studies of the distribution of TGF-β protein and mRNA using immunohistochemistry and in situ hybridisation confirmed the low levels of TGF-β1 protein and mRNA observed in QPCR and demonstrated distinct centroperipheral gradients in the photoreceptor layer for TGF-β2 and TGF-β3. Relative high amounts of TGF-β in the fovea could affect vascular patterning due to TβRI seen in astrocytes which lead the blood vessels at the foveal rim at the level of the ganglion cell plexus. TGF-β2 and TGF-β3 expression is detected before formation of the foveal avascular zone (FAZ) at fd64 (~15WG) - fd73 (~17WG) with levels peaking in the foveal region at fd105 (~25WG) by the time the FAZ forms. Conclusions: This thesis has shown that EC proliferation in the choriocapillaris does not appear to be promoted by increased metabolic activity in central retinal neurons as reduced rates of EC proliferation in the ‘foveal’ chorioretinal location were observed at all ages studied between 14 and 18.5WG. The findings suggest that mechanisms regulating proliferation and growth of the choroidal vasculature are independent of differentiation in the neural retina and are therefore different to those governing the formation of the retinal vasculature. All TGF-β isoforms are expressed in developing and adult human and macaque retina with TGF-β2 being the predominant isoform. TGF-β isoforms are more abundant in central compared to peripheral retina and in developing compared to adult retina. Centro-peripheral gradients of TGF-β2 and TGF-β3 across the photoreceptor layer and TβRI on astrocytes support the presence of TGF-β in the fovea as an antiproliferative and antiangiogenic factor by helping to define the FAZ early in development, well before 23-25 WG in humans and before fd100 in macaques.

<p>After finishing a human genome reference sequence in 2002, the genomics community has</p><p>turned to the task of interpreting it. A primary focus is to identify and characterize not only</p><p>protein-coding genes, but all functional elements in the genome. The effort has identified</p><p>millions of regulatory elements across species and in hundreds of human cell-types. Nearly</p><p>all identified regulatory elements are found in non-coding DNA, hypothesizing a function</p><p>for previously unannotated sequence. The ability to identify regulatory DNA genome-wide</p><p>provides a new opportunity to understand gene regulation and to ask fundamental questions</p><p>in diverse areas of biology.</p><p>One such area is the aim to understand the molecular basis for phenotypic differences</p><p>between humans and other primates. These phenotypic differences are partially driven</p><p>by mutations in non-coding regulatory DNA that alter gene expression. This hypothesis</p><p>has been supported by differential gene expression analyses in general, but we have not</p><p>yet identified specific regulatory variants responsible for differences in transcription and</p><p>phenotype. I have worked to identify regulatory differences in the same cell-type isolated</p><p>from human, chimpanzee, and macaque. Most regulatory elements were conserved among</p><p>all three species, as expected based on their central role in regulating transcription. How-</p><p>ever, several hundred regulatory elements were gained or lost on the lineages leading to</p><p>modern human and chimpanzee. Species-specific regulatory elements are enriched near</p><p>differentially expressed genes, are positively correlated with increased transcription, show</p><p>evidence of branch-specific positive selection, and overlap with active chromatin marks.</p><p>ivSpecies-specific sequence differences in transcription factor motifs found within this regu-</p><p>latory DNA are linked with species-specific changes in chromatin accessibility. Together,</p><p>these indicate that species-specific regulatory elements contribute to transcriptional and</p><p>phenotypic differences among primate species.</p><p>Another fundamental function of regulatory elements is to define different cell-types in</p><p>multicellular organisms. Regulatory elements recruit transcription factors that modulate</p><p>gene expression distinctly across cell-types. In a study of 112 human cell-types, I classified</p><p>regulatory elements into clusters based on regulatory signal tissue specificity. I then used</p><p>these to uncover distinct associations between regulatory elements and promoters, CpG-</p><p>islands, conserved elements, and transcription factor motif enrichment. Motif analysis</p><p>identified known and novel transcription factor binding motifs in cell-type-specific and</p><p>ubiquitous regulatory elements. I also developed a classifier that accurately predicts cell-</p><p>type lineage based on only 43 regulatory elements and evaluated the tissue of origin for</p><p>cancer cell-types. By correlating regulatory signal and gene expression, I predicted target</p><p>genes for more than 500k regulatory elements. Finally, I introduced a web resource to</p><p>enable researchers to explore these regulatory patterns and better understand how expression</p><p>is modulated within and across human cell-types.</p><p>Regulation of gene expression is fundamental to life. This dissertation uses identified</p><p>regulatory DNA to better understand regulatory systems. In the context of either evolution-</p><p>ary or developmental biology, understanding how differences in regulatory DNA contribute</p><p>to phenotype will be central to completely understanding human biology.</p> / Dissertation

Many studies have documented adverse affects to inequitable situations in non-human primates. The behaviors that have predominantly been examined include food taking, collecting, giving, and refusals between the primate subjects and the experimenters. However, no studies had looked at the affective responses to inequity in primates. In a recent study, four-year old children who were rewarded inequitably accepted the reward, however they showed affective signs of dissatisfaction. For this study, we looked for affective displays in capuchins during inequitable exchange tasks. We predicted that the capuchins that were experiencing inequity would show more signs of agitation and aggression than those in equitable situations. We saw no increase in agitation or aggression when subjects were treated inequitably. There was higher aggression towards partners who received the lower reward in inequitable situations and less agitation seen by partners during frustration controls. Future studies may find our hypothesized results using different methodologies.

<p>There is a long-standing claim that humans and nonhuman primates share an evolutionarily ancient system of nonverbal number representation. By and large, the focus in the field has been on providing existence proofs of numerical competence in wide-ranging taxa or using individual species as models for comparisons with humans. Recent findings in numerical cognition have suggested that evidence for approximate numerical abilities in nonhuman species may indicate that humans and animals share a cognitive system for representing numerosities nonverbally. To date, little is known about the contextual and quantitative limits of that system, or how those limits differ between species. The studies presented here take a comparative, behavioral approach to characterizing species differences and similarities in the approximate number system, and the contexts that affect that system. Collectively, this set of studies provides evidence that the approximate number system evolved in primates as a malleable system in which numerical representations are accessed spontaneously and improved through training. Despite the sensitivity of the system to experience and context individual differences in sensitivity are greater than species differences suggesting that the selective pressures that constrained its evolution were early and general and that species variation in social group size and diet have less influence on the ANS. Finally my studies indicate that the ANS supports approximate arithmetic and is consistent with the idea that ANS representations evolved to allow animals to calculate the world around them.</p> / Dissertation

<p>Reconstructing locomotor patterns from fossils is crucial for understanding the origins of primates and important transitions in various primate clades. Recent studies suggest that the semicircular canals of the inner ear provide evidence about locomotion. The canals sense rotational head accelerations and drive reflexes essential for normal movement. Because bony aspects of canal morphology influence canal sensitivity, this system can be studied in osteologic specimens and fossils. Variation in canal morphology in living and, by inference, extinct primates has been attributed to interspecific differences in locomotor behavior. However, the manner in which movement selects for canal morphology is debated, alternative scenarios are plausible, and no relevant measurements are available documenting head movements in primates.</p><p>To refine proposed links between canal morphology and locomotor function, and to resolve conflicting functional interpretations, this study examines head rotations in lemurs and lorises exhibiting diverse locomotor behaviors. Three-dimensional kinematic analyses were used to characterize angular velocities of the head during locomotion. These data are used to test hypotheses concerning intraspecific, interspecific, and body-size dependent variation in head rotations. Cranial CT scans are used to model canal sensitivity to rotations in different directions. Observed patterns of head rotation are compared to predicted patterns of sensitivity to test hypotheses about the relationship between locomotor behavior and canal design.</p><p>Evaluation of existing locomotor inferences reveals that brain size exerts a significant effect on canal size and that the prevailing equations for predicting agility from body and canal size are highly inaccurate. Intraspecific comparisons between maps of observed angular velocity and predicted sensitivity allow identification of map types associated with different general locomotor modes and do not support existing hypotheses about the primary selective forces acting on canal morphology. The new data are used to formulate and test a novel "fast-accurate hypothesis" to explain why all vertebrates are more sensitive to rotations about some axes than others. The fast-accurate hypothesis stipulates that angular velocities presented about axes of mean sensitivity are most accurately interpreted by the brain, and that selection aligns axes of mean sensitivity with axes of habitually fast rotation because accurate perception of rapid rotations confers survival benefit. The fast-accurate hypothesis was used to predict which features of the canals should be correlated with high mean angular velocities of head movement. Novel equations that predict behavior from these newly identified canal morphologies were generated and found to outperform existing equations when tested on the original sample of 11 strepsirrhine species.</p> / Dissertation

<p>Primates and many other animals that move in an arboreal environment often cling, sometimes for long periods, on vertical supports. Primates, however, face a special challenge in that almost all primates bear nails on the tips of their digits rather than claws. Squirrels and other arboreal animals possess claws and/or adhesive pads on their digits in order to hold their weight on vertical substrates. Assuming the ancestral primate was arboreal and lost claws prior to the radiation of primates this paradox has important implications and raises a significant question about living primates and early primate evolution: how can primates maintain vertical postures without claws and how did early primates meet this challenge? Primate vertically clinging and grasping postures (VCG) have been studied in the wild and theoretical models of VCG postures have been described. This dissertation builds on this work, by studying the biomechanics of VCG postures in primates. Based on mechanical models, it was hypothesized VCG posture in primates will vary in three ways. </p><p>Hypothesis 1: Species with different morphological features associated with different locomotor modes will vertically cling and grasp in different ways. </p><p>Hypothesis 2: As substrate size increases, primates will place their arms to the side of the support and adjust posture and muscle recruitment in order to maintain a necessary tangential to normal force ratio to resist gravity. </p><p>Hypothesis 3: On substrates of the same relative size, larger animals should be less effective at maintaining VCG postures due to scaling relationships between muscle strength and body mass. </p><p>The sample consisted of multiple individuals from eight strepsirrhine species at the Duke Lemur Center. The sample varied in locomotor mode--habitual vertical clinging and leaping (VCL) compared to less specialized arboreal quadrupeds--and body mass--100 to 4,000 grams. Subjects were videorecorded while holding VCG postures on substrates of increasing size. Substrate preference data were calculated based on frequency and duration of VCG postures on each substrate. Qualitative kinematic data were recorded for a maximum of thirty trials per individual, per substrate. Angular data were calculated for forelimbs and hindlimbs from these videos for ten trials per individual per substrate. In addition, kinetic data from an imbedded force transducer were collected for two species that vary in locomotor mode, but not body mass. </p><p>There are several significant and relevant results from this study that address both primate functional anatomy and locomotor evolution. Hypothesis one was supported by hand and hindlimb joint postures, shown to be highly sensitive to locomotor mode. VCL primates exhibited deeply flexed limbs and more hand grasping (wrapping around the substrate) versus parallel hand postures and use of bowed finger postures compared to less specialized primates. Kinetically, species were shown to bear the majority of their weight in their hindlimbs relative to their forelimbs. The forelimb joints and foot showed little variation by habitual locomotor mode. Hypothesis two found support in that species tend to prefer smaller substrates, clinging less frequently for shorter durations as substrate size increases. Hand posture changed as size increased, as primates (except for the slow lorises) in this study grasped with their pollex on smaller substrates, but the pollex disengaged in grasping on larger substrates. Hypothesis three was not supported; body mass did not influence VCG postures. </p><p>Taken together, the finding that the forelimb held a wide range of postures on each substrate size for all species and played a limited role in weight-bearing suggests the forelimb free to move (to adjust posture and or forage). The hindlimb plays a more specific role in weight-bearing and is more sensitive to variations in primate anatomy. Additionally, these findings lead to hypotheses concerning the relatively short pollexes of primates, and that the ancestral primate was smaller than 100g and preferred small substrates as found in a fine-branch niche.</p> / Dissertation