Browsing by Subject "Monkey"

Now showing 1 - 4 of 4
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    Bidirectional gut-to-brain and brain-to-gut propagation of synucleinopathy in non-human primates
    (Oxford University Press, 2020-05-07) Herrero Ezquerro, María Trinidad; Arotcarena, Marie-Laure; Dovero, Sandra; Prigent, Alice; Bourdenx, Mathieu; Camus, Sandrine; Porras, Gregory; Thiolat, Marie-Laure; Tasselli, Maddalena; Aubert, Philippe; Kruse, Niels; Mollenhauer, Brit; Trigo Damas, Ines; Estrada, Cristina; Garcia-Carrillo, Nuria; Vaikath, Nishant; El-Agnaf, Omar M.A.; Vila, Miquel; Obeso, Jose A.; Derkinderen, Pascal; Dehay, Benjamin; Bezard, Erwan; Anatomía Humana y Psicobiología
    In Parkinson’s disease, synucleinopathy is hypothesized to spread from the enteric nervous system, via the vagus nerve, to the CNS. Here, we compare, in baboon monkeys, the pathological consequences of either intrastriatal or enteric injection of a-synucleincontaining Lewy body extracts from patients with Parkinson’s disease. This study shows that patient-derived a-synuclein aggregates are able to induce nigrostriatal lesions and enteric nervous system pathology after either enteric or striatal injection in a non-human primate model. This finding suggests that the progression of a-synuclein pathology might be either caudo-rostral or rostro-caudal, varying between patients and disease subtypes. In addition, we report that a-synuclein pathological lesions were not found in the vagal nerve in our experimental setting. This study does not support the hypothesis of a transmission of a-synuclein pathology through the vagus nerve and the dorsal motor nucleus of the vagus. Instead, our results suggest a possible systemic mechanism in which the general circulation would act as a route for long-distance bidirectional transmission of endogenous a-synuclein between the enteric and the central nervous systems. Taken together, our study provides invaluable primate data exploring the role of the gut-brain axis in the initiation and propagation of Parkinson’s disease pathology and should open the door to the development and testing of new therapeutic approaches aimed at interfering with the development of sporadic Parkinson’s disease.
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    Carbohydrate cytochemistry of bonnet monkey (Macaca radiaca) nasal epithelium. Response to ambient levels of ozone
    (Murcia : F. Hernández, 1992) Dimitriadis, V.K.
    The main purpose of this study was to determine whether exposures to ambient levels of ozone induced changes in the carbohydrate content in the anterior nasal cavity of bonnet monkey. Monkeys were exposed to 0.00. 0.15, or 0.30 ppm of ozone for 6 or 90 days, 8 hours / day. Monkeys treated for 90 days to 0.15 or 0.30 ppm of ozone displayed damaged ciliated cells and a new cell type in their respiratory nasal epithelium, the «intermediate» cells possessing morphological characteristics of both ciliated and secretory cells. Characterization of the secretory cell carbohydrates with the PA-TCH-SP, HID-TCH-SP and LID-TCH-SP techniques indicated the existence of periodate-reactive sulfated and carboxylated polysaccharides in both treated and control monkeys. Ozone-inhalation, however, induced the appearance of a large number of mucous cells with dilated cisternae of rough endoplasmic reticulum compared to controls, which reacted negatively for sugar presence. In addition, in the respiratory epithelium ozone induced the increase of cells with intracytoplasmic lumina containing material reacted positively for sulfated and carboxylated polysaccharides.
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    Partial urethral obstruction enhances NADPH-diaphorase activity in the monkey (Macaca fascicularis) bladder: light and electron microscopic studies
    (Murcia : F. Hernández, 2006) Kumar, S.D.; Tay, S.S.W.; Ling, E. A.
    The effect of partially obstructing the urethra on the nicotinamide adenine dinucleotide phosphatediaphorase (NADPH-d) activity in neurons of the intramural ganglia of the monkey (Macaca fascicularis) bladder was examined by light and electron microscopy. Partial urethral ligation was done in adult male monkeys. The animals were sacrificed 2, 4 weeks after partial urethral obstruction. This was compared to controls (normal and sham operated). Urethral obstructed animals were observed to have increased urinary frequency and decreased urinary flow rate. Two weeks after urethral obstruction, the overall NADPH-d activity in the intramural ganglia of the bladder base was enhanced compared to control animals. The frequency of intensely stained NADPH-d positive neurons was increased compared to the control animals. About one-third of intensely stained NADPH-d positive neurons appeared to undergo degenerative changes. At 4 weeks after urethral obstruction, a wide occurrence of NADPH-d positive neurons in advanced stages of degeneration in the bladder base was observed. Cellular debris was strewn among normal looking ganglion cells and along the nerve processes. The proportion of intensely stained NADPH-d positive neurons was relatively lower than the controls. The total number of NADPH-d positive neurons and the nerve fibres in the entire bladder was significantly reduced when compared to control animals. Electron microscopy showed some NADPH-d activity in intramural ganglion cells in 2 weeks after partial urethral obstruction. NADPH-d reaction product (formazan) was deposited on the membranes of the rough endoplasmic reticulum, and the outer membranes of some mitochondria in the intramural neuron. At 4 weeks after urethral obstruction, NADPH-d was present in the membrane of the mitochondria and some mitochondria appeared swollen with disrupted cristae. Present results show that NADPH-d activity in neurons of the intramural ganglia of the monkey (Macaca fascicularis) urinary bladder was increased after two weeks and reduced after 4 weeks of partial urethral obstruction. It is speculated that the increased NADPH-d activity associated with partial urethral obstruction would lead to neuronal damage and death, which may contribute to detrusor overactivity. However, it warrants further investigation to understand the mechanism of neuronal cell death after partial urethral obstruction.
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    Ultrastructure of the area postrema of the monkey, Macaca fascic ularis
    (Murcia : F. Hernández, 1987) Ling, E. A.; Wong, W.C.
    The area postrema of the monkey, Macaca fascicularis, were a pair of oval organs at the caudal end of the floor of fourth ventricle. Their ependymal lining was covered by well-developed microvilli with occasional overlying supraependymal cells. Two types of lining cells were present: pyramidad- and flattened cells. The pyramidal cell showed a long extending basal process resting on the underlying blood vessels. In transmission electron microscopy, the organ showed numerous fenestrated sinusoids characterized by a distinct perivascular space containing mast cells, macrophages and collagen fibrils. The parenchyma of the organ was composed of neurons and glial elements. Only one type of neuron ranging from 9.5 to I5pm could be distinguished. The neurons contained an indented nucleus surrounded by organelle rich cytoplasm. The soma of the neuron was enclosed by glial element resembling astrocyte. The glial processes terminated on the blood vessel where they were "tunnelled" by a variable number of nerve fibres some of which gained a direct access to the externa1 basal lamina of the perivascular space. Synapses in the neuropil predominantly of the axodendritic variety were observed. h o n terminals containing round agranular vesicles were seen to make synaptic contacts with the neurona1 soma. No structural changes were observed in the area postrema following bilateral cervical vagotomy. However, degenerating axon terminals were observed in the subpostremal zone 7, 14 and 21 days after vagotomy suggesting a direct afferent projection into this region.