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Large interneurons of granular layer of cerebellar cortex  [PDF]
Stepanenko A.Yu.
Морфолог?я , 2009,
Abstract: Large interneurons of cerebellar cortex are described. Golgi Cells lie mostly in vestibulocerebellum. Their dendrites contact with parallel fibers and mossy fibers, axons terminate in glomerules. Golgi Cells inhibit granule cells and induce their synchronic rhythmic activity. Lugaro Cells lie in horizontal plane under ganglionic layer, form clasters and more frequent in paleocerebellum. Dendrites contact with collaterals Purkinje and basket cells axones; axones terminate on basket and stellate cell. Lugaro Cells stimulate Purkinje Cells by inhibiting of inhibitory stellate and basket cells. Candelabrum Cells are inhibitory interneurons which lie between Purkinje cells bodies. Axon forms horizontal branches in parasagittal plane in molecular layer, and vertical ones which resemble candelabrum. Unipolar brush cells – excitatory interneuron of the cerebel-lum, form system of intrinsic mossy fibers. Single axon forms numerous brush-like branches – dendrioles, which end in one common glomerules, axon collaterals terminate in another one. Synamortic neurons contact with neurons of cerebellar nuclei and another region of the cortex. Perivascular neurons regulate local blood flow.
Morphology and connections of intratrigeminal cells and axons in the macaque monkey  [PDF]
Susan Warren,Paul J. May
Frontiers in Neuroanatomy , 2013, DOI: 10.3389/fnana.2013.00011
Abstract: Trigeminal primary afferent fibers have small receptive fields and discrete submodalities, but second order trigeminal neurons often display larger receptive fields with complex, multimodal responses. Moreover, while most large caliber afferents terminate exclusively in the principal trigeminal nucleus, and pars caudalis (sVc) of the spinal trigeminal nucleus receives almost exclusively small caliber afferents, the characteristics of second order neurons do not always reflect this dichotomy. These surprising characteristics may be due to a network of intratrigeminal connections modifying primary afferent contributions. This study characterizes the distribution and morphology of intratrigeminal cells and axons in a macaque monkeys. Tracer injections centered in the principal nucleus (pV) and adjacent pars oralis retrogradely labeled neurons bilaterally in pars interpolaris (sVi), but only ipsilaterally, in sVc. Labeled axons terminated contralaterally within sVi and caudalis. Features of the intratrigeminal cells in ipsilateral sVc suggest that both nociceptive and non-nociceptive neurons project to principalis. A commissural projection to contralateral principalis was also revealed. Injections into sVc labeled cells and terminals in pV and pars oralis on both sides, indicating the presence of bilateral reciprocal connections. Labeled terminals and cells were also present bilaterally in sVi and in contralateral sVc. Interpolaris injections produced labeling patterns similar to those of sVc. Thus, the rostral and caudal poles of the macaque trigeminal complex are richly interconnected by ipsilateral ascending and descending connections providing an anatomical substrate for complex analysis of oro-facial stimuli. Sparser reciprocal crossed intratrigeminal connections may be important for conjugate reflex movements, such as the corneal blink reflex.
Identification of Hepatocystis species in a macaque monkey in northern Myanmar
Chang Q, Sun X, Wang J, Yin J, Song J, Peng S, Lu H, Zhou H, Jiang N, Chen Q
Research and Reports in Tropical Medicine , 2011, DOI: http://dx.doi.org/10.2147/RRTM.S27182
Abstract: entification of Hepatocystis species in a macaque monkey in northern Myanmar Original Research (1628) Total Article Views Authors: Chang Q, Sun X, Wang J, Yin J, Song J, Peng S, Lu H, Zhou H, Jiang N, Chen Q Published Date November 2011 Volume 2011:2 Pages 141 - 146 DOI: http://dx.doi.org/10.2147/RRTM.S27182 Qiaocheng Chang1,*, Xiaodong Sun2,*, Jian Wang2,*, Jigang Yin1, Junpeng Song1, Shuai Peng1, Huijun Lu1, Hongning Zhou2, Ning Jiang1, Qijun Chen1,3 1Key Laboratory of Zoonosis, Jilin University, Changchun; 2Institute for Parasitic Disease Control of Yunnan Province, Puer City, Yunnan; 3Institute of Pathogen Biology, Chinese Academy of Medical Sciences, Beijing, China *These authors contributed equally to this work Background: Long-tailed and pig-tailed macaque monkeys are natural hosts of Plasmodium knowlesi, which has been identified as a fifth malaria parasite infecting humans. In this study, we investigated possible infection by this Plasmodium parasite in macaque monkeys using a combination of polymerase chain reaction amplification and sequencing. Methods: Forty-five blood samples were obtained in 2010 from macaques in northern Myanmar near Yunnan Province of China and investigated for possible infection with Plasmodium species using a nested polymerase chain reaction method for amplification of 18S SSU rRNA genes. Results: Positive amplification was obtained from one monkey, and both sequence and phylogenetic analysis indicated that the parasite was of the Hepatocystis species lineage. Conclusion: The results suggest that a combination of polymerase chain reaction amplification and sequence identification would be necessary for detection of Plasmodium knowlesi infection in both humans and its natural hosts.
Identification of Hepatocystis species in a macaque monkey in northern Myanmar  [cached]
Chang Q,Sun X,Wang J,Yin J
Research and Reports in Tropical Medicine , 2011,
Abstract: Qiaocheng Chang1,*, Xiaodong Sun2,*, Jian Wang2,*, Jigang Yin1, Junpeng Song1, Shuai Peng1, Huijun Lu1, Hongning Zhou2, Ning Jiang1, Qijun Chen1,31Key Laboratory of Zoonosis, Jilin University, Changchun; 2Institute for Parasitic Disease Control of Yunnan Province, Puer City, Yunnan; 3Institute of Pathogen Biology, Chinese Academy of Medical Sciences, Beijing, China *These authors contributed equally to this workBackground: Long-tailed and pig-tailed macaque monkeys are natural hosts of Plasmodium knowlesi, which has been identified as a fifth malaria parasite infecting humans. In this study, we investigated possible infection by this Plasmodium parasite in macaque monkeys using a combination of polymerase chain reaction amplification and sequencing.Methods: Forty-five blood samples were obtained in 2010 from macaques in northern Myanmar near Yunnan Province of China and investigated for possible infection with Plasmodium species using a nested polymerase chain reaction method for amplification of 18S SSU rRNA genes.Results: Positive amplification was obtained from one monkey, and both sequence and phylogenetic analysis indicated that the parasite was of the Hepatocystis species lineage.Conclusion: The results suggest that a combination of polymerase chain reaction amplification and sequence identification would be necessary for detection of Plasmodium knowlesi infection in both humans and its natural hosts.Keywords: Plasmodium knowlesi, monkey, parasite, malaria
A case of polymicrogyria in macaque monkey: impact on anatomy and function of the motor system
Eric Schmidlin, Christophe Jouffrais, Patrick Freund, Patrizia Wannier-Morino, Marie-Laure Beaud, Eric M Rouiller, Thierry Wannier
BMC Neuroscience , 2009, DOI: 10.1186/1471-2202-10-155
Abstract: The examination of the brain showed a large number of microgyri at macro- and microscopic levels, covering mainly the frontoparietal regions. The layered cortical organization was locally disrupted and the number of SMI-32 stained pyramidal neurons in the cortical layer III of the presumed motor cortex was reduced. We compared the distribution of labelled CS axons in the PMG monkey at spinal cervical level C5. The cumulated length of CS axon arbors in the spinal grey matter was not significantly different in the PMG monkey. In the red nucleus, numerous neurons presented large vesicles. We also assessed its motor performances by comparing its capacity to execute a complex reach and grasp behavioral task. The PMG monkey exhibited an increase of reaction time without any modification of other motor parameters, an observation in line with a normal CS tract organisation.In spite of substantial cortical malformations in the frontal and parietal lobes, the PMG monkey exhibits surprisingly normal structure and function of the corticospinal system.Polymicrogyria is a developmental malformation of the cerebral cortex, characterized by multiple small gyri with abnormal cortical lamination [1]. PMG can be unilateral or bilateral and its extent varies from focal PMG in otherwise normal brain to diffuse PMG with multiple other brain abnormalities. The spectrum of clinical manifestations ranges from normal individuals, with only selective impairment of cognitive function [2] and no or easily controlled epilepsy, to patients with severe encephalopathy and intractable epilepsy [3]. Motor and cognitive deficits such as a delay in development [4], or congenital contractures [5] are commonly described in patients suffering from PMG. Microscopically, two histological types of PMG were recognized: a simplified four layered form and an unlayered form [6]. The two types of PMG may coexist in contiguous cortical areas [7]. Recent report provides evidence that PMG areas are functional [8].Th
Measurement of neuronal activity in a macaque monkey in response to animate images using near-infrared spectroscopy  [PDF]
Masumi Wakita,Masahiro Shibasaki,Takashi Ishizuka,Joerg Schnackenberg,Michiyuki Fujiawara,Nobuo Masataka
Frontiers in Behavioral Neuroscience , 2010, DOI: 10.3389/fnbeh.2010.00031
Abstract: Near-infrared spectroscopy (NIRS) has been used extensively for functional neuroimaging over the past decade, in part because it is considered a powerful tool for investigating brain function in human infants and young children, for whom other neuroimaging techniques are not suitable. In particular, several studies have measured hemodynamic responses in the occipital region in infants upon exposure to visual stimuli. In the present study, we used a multi-channel NIRS to measure neuronal activity in a macaque monkey who was trained to watch videos showing various circus animals performing acrobatic activities without fixing the head position of the monkey. Cortical activity from the occipital region was measured first by placing a probe comprising a 3 × 5 array of emitters and detectors (2 × 4 cm) on the area (area 17), and the robustness and stability of the results were confirmed across sessions. Cortical responses were then measured from the dorsofrontal region. The oxygenated hemoglobin signals increased in area 9 and decreased in area 8b in response to viewing the videos. The results suggest that these regions are involved in cognitive processing of visually presented stimuli. The monkey showed positive responsiveness to the stimuli from the affective standpoint, but its attentional response to them was an inhibitory one.
The compartmental restriction of cerebellar interneurons  [PDF]
G. Giacomo Consalez,Richard Hawkes
Frontiers in Neural Circuits , 2013, DOI: 10.3389/fncir.2012.00123
Abstract: The Purkinje cells (PC's) of the cerebellar cortex are subdivided into multiple different molecular phenotypes that form an elaborate array of parasagittal stripes. This array serves as a scaffold around which afferent topography is organized. The ways in which cerebellar interneurons may be restricted by this scaffolding are less well-understood. This review begins with a brief survey of cerebellar topography. Next, it reviews the development of stripes in the cerebellum with a particular emphasis on the embryological origins of cerebellar interneurons. These data serve as a foundation to discuss the hypothesis that cerebellar compartment boundaries also restrict cerebellar interneurons, both excitatory [granule cells, unipolar brush cells (UBCs)] and inhibitory (e.g., Golgi cells, basket cells). Finally, it is proposed that the same PC scaffold that restricts afferent terminal fields to stripes may also act to organize cerebellar interneurons.
Tracking the eye non-invasively: simultaneous comparison of the scleral search coil and optical tracking techniques in the macaque monkey  [PDF]
Daniel L. Kimmel,Dagem Mammo,William T. Newsome
Frontiers in Behavioral Neuroscience , 2012, DOI: 10.3389/fnbeh.2012.00049
Abstract: From human perception to primate neurophysiology, monitoring eye position is critical to the study of vision, attention, oculomotor control, and behavior. Two principal techniques for the precise measurement of eye position—the long-standing sclera-embedded search coil and more recent optical tracking techniques—are in use in various laboratories, but no published study compares the performance of the two methods simultaneously in the same primates. Here we compare two popular systems—a sclera-embedded search coil from C-N-C Engineering and the EyeLink 1000 optical system from SR Research—by recording simultaneously from the same eye in the macaque monkey while the animal performed a simple oculomotor task. We found broad agreement between the two systems, particularly in positional accuracy during fixation, measurement of saccade amplitude, detection of fixational saccades, and sensitivity to subtle changes in eye position from trial to trial. Nonetheless, certain discrepancies persist, particularly elevated saccade peak velocities, post-saccadic ringing, influence of luminance change on reported position, and greater sample-to-sample variation in the optical system. Our study shows that optical performance now rivals that of the search coil, rendering optical systems appropriate for many if not most applications. This finding is consequential, especially for animal subjects, because the optical systems do not require invasive surgery for implantation and repair of search coils around the eye. Our data also allow laboratories using the optical system in human subjects to assess the strengths and limitations of the technique for their own applications.
Spinogenesis and Pruning in the Anterior Ventral Inferotemporal Cortex of the Macaque Monkey: An Intracellular Injection Study of Layer III Pyramidal Cells  [PDF]
Guy N. Elston,Tomofumi Oga,Ichiro Fujita
Frontiers in Neuroanatomy , 2011, DOI: 10.3389/fnana.2011.00042
Abstract: Pyramidal cells grow and mature at different rates among different cortical areas in the macaque monkey. In particular, differences across the areas have been reported in both the timing and magnitude of growth, branching, spinogenesis, and pruning in the basal dendritic trees of cells in layer III. Presently available data suggest that these different growth profiles reflect the type of functions performed by these cells in the adult brain. However, to date, studies have focused on only a relatively few cortical areas. In the present investigation we quantified the growth of the dendritic trees of layer III pyramidal cells in the anterior ventral portion of cytoarchitectonic area TE (TEav) to better comprehend developmental trends in the cerebral cortex. We quantified the growth and branching of the dendrities, and spinogenesis and pruning of spines, from post-natal day 2 (PND2) to four and a half years of age. We found that the dendritic trees increase in size from PND2 to 7 months of age and thereafter became smaller. The dendritic trees became increasingly more branched from PND2 into adulthood. There was a two-fold increase in the number of spines in the basal dendritic trees of pyramidal cells from PND2 to 3.5 months of age and then a 10% net decrease in spine number into adulthood. Thus, the growth profile of layer III pyramidal cells in the anterior ventral portion of the inferotemporal cortex differs to that in other cortical areas associated with visual processing.
Does the Macaque Monkey Provide a Good Model for Studying Human Executive Control? A Comparative Behavioral Study of Task Switching  [PDF]
Luana Caselli, Leonardo Chelazzi
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0021489
Abstract: The ability to swiftly and smoothly switch from one task set to another is central to intelligent behavior, because it allows an organism to flexibly adapt to ever changing environmental conditions and internal needs. For this reason, researchers interested in executive control processes have often relied on task-switching paradigms as powerful tools to uncover the underlying cognitive and brain architecture. In order to gather fundamental information at the single-cell level, it would be greatly helpful to demonstrate that non-human primates, especially the macaque monkey, share with us similar behavioral manifestations of task-switching and therefore, in all likelihood, similar underlying brain mechanisms. Unfortunately, prior attempts have provided negative results (e.g., Stoet & Snyder, 2003b), in that it was reported that macaques do not show the typical signature of task-switching operations at the behavioral level, represented by switch costs. If confirmed, this would indicate that the macaque cannot be used as a model approach to explore human executive control mechanisms by means of task-switching paradigms. We have therefore decided to re-explore this issue, by conducting a comparative experiment on a group of human participants and two macaque monkeys, whereby we measured and compared performance costs linked to task switching and resistance to interference across the two species. Contrary to what previously reported, we found that both species display robust task switching costs, thus supporting the claim that macaque monkeys provide an exquisitely suitable model to study the brain mechanisms responsible for maintaining and switching task sets.
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