Read by QxMD icon Read

Macaque brain

Nathan McDannold, Margaret Livingstone, Can Barış Top, Jonathan Sutton, Nick Todd, Natalia Vykhodtseva
This study investigated thermal ablation and skull-induced heating with a 230 kHz transcranial MRI-guided focused ultrasound (TcMRgFUS) system in nonhuman primates. We evaluated real-time acoustic feedback and aimed to understand whether cavitation contributed to the heating and the lesion formation. In four macaques, we sonicated thalamic targets at acoustic powers of 34-560 W (896-7590 J). Tissue effects evaluated with MRI and histology were compared to MRI-based temperature and thermal dose measurements, acoustic emissions recorded during the experiments, and acoustic and thermal simulations...
October 14, 2016: Physics in Medicine and Biology
David B Hanbury, Ann M Peiffer, Greg Dugan, Rachel N Andrews, J Mark Cline
In this study, the effects of a potentially lethal radiation exposure on the brain for long-term cognitive sequelae were investigated, using Rhesus macaques ( Macaca mulatta ) adopted from other facilities after analysis of acute radiation response via the Centers for Medical Countermeasures against Radiation (CMCR) network. Fifty-nine animals were given the opportunity to participate in cognitive cage-side testing. The animals that received single-dose gamma irradiation were significantly less likely to engage in cognitive testing than the controls, suggesting that irradiated animals may have differences in cognitive ability...
October 14, 2016: Radiation Research
Maria Dadarlat, Philip Sabes
Naturalistic control of brain-machine interfaces will require artificial proprioception, potentially delivered via intracortical microstimulation (ICMS).We have previously shown that multi-channel ICMS can guide a monkey reaching to unseen targets in a planar workspace. Here, we expand on that work, asking how ICMS is decoded into target angle and distance by analyzing the performance of a monkey when ICMS feedback was degraded. From the resulting pattern of errors, we found that the animal's estimate of target direction was consistent with a weighted circular-mean strategy-close to the optimal decoding strategy given the ICMS encoding...
October 11, 2016: IEEE Transactions on Haptics
Christian Wächter, Lee E Eiden, Nedye Naumann, Candan Depboylu, Eberhard Weihe
BACKGROUND: The majority of investigations on HIV-associated neurocognitive disorders (HAND) neglect the cerebellum in spite of emerging evidence for its role in higher cognitive functions and dysfunctions in common neurodegenerative diseases. METHODS: We systematically investigated the molecular and cellular responses of the cerebellum as contributors to lentiviral infection-induced neurodegeneration, in the simian immunodeficiency virus (SIV)-infected rhesus macaque model for HIV infection and HAND...
October 14, 2016: Journal of Neuroinflammation
K G Sorwell, L Renner, A R Weiss, M Neuringer, S G Kohama, H F Urbanski
Estradiol supplementation has been shown to enhance cognitive performance in old ovariectomized rhesus macaques (Macaca mulatta). To determine if similar benefits could be achieved in perimenopausal animals using alternative hormonal supplements we administered dehydroepiandrosterone (DHEA) to old ovary-intact female rhesus macaques for ~2.5 months. Using computerized touchscreen memory tasks, including delayed response (DR) and delayed matching-to-sample (DMS), we observed improved performance with time in all of the animals but failed to detect a significant effect of DHEA...
October 13, 2016: Genes, Brain, and Behavior
Katharine A Shapcott, Joscha T Schmiedt, Richard C Saunders, Alexander Maier, David A Leopold, Michael C Schmid
A fundamental property of brain function is that the spiking activity of cortical neurons is variable and that some of this variability is correlated between neurons. Correlated activity not due to the stimulus arises from shared input but the neuronal circuit mechanisms that result in these noise correlations are not fully understood. Here we tested in the visual system if correlated variability in mid-level area V4 of visual cortex is altered following extensive lesions of primary visual cortex (V1). To this end we recorded longitudinally the neuronal correlations in area V4 of two behaving macaque monkeys before and after a V1 lesion while the monkeys fixated a grey screen...
October 10, 2016: Scientific Reports
Tomofumi Oga, Tsuguhisa Okamoto, Ichiro Fujita
Neurons in the mammalian primary visual cortex (V1) are systematically arranged across the cortical surface according to the location of their receptive fields (RFs), forming a visuotopic (or retinotopic) map. Within this map, the foveal visual field is represented by a large cortical surface area, with increasingly peripheral visual fields gradually occupying smaller cortical areas. Although cellular organization in the retina, such as the spatial distribution of ganglion cells, can partially account for the eccentricity-dependent differences in the size of cortical representation, whether morphological differences exist across V1 neurons representing different eccentricities is unclear...
2016: Frontiers in Neural Circuits
Akiya Watakabe, Osamu Sadakane, Katsusuke Hata, Masanari Ohtsuka, Masafumi Takaji, Tetsuo Yamamori
It is important to study the neural connectivities and functions in primates. For this purpose, it is critical to be able to transfer genes to certain neurons in the primate brain so that we can image the neuronal signals and analyze the function of the transferred gene. Toward this end, our team has been developing gene transfer systems using viral vectors. In this review, we summarize our current achievements as follows. 1) We compared the features of gene transfer using five different AAV serotypes in combination with three different promoters, namely, CMV, mouse CaMKII (CaMKII), and human synapsin 1 (hSyn1), in the marmoset cortex with those in the mouse and macaque cortices...
October 5, 2016: Developmental Neurobiology
Young-A Lee, Valentine Pollet, Akemi Kato, Yukiori Goto
In biomedical research of brain dysfunction in psychiatric disorders, utilization of animal models is essential. However, translation of findings in animal models into the realm of human clinical conditions requires reliable biomarkers that are assessed with the methods mutually employed in animal models and human patients. Near-infrared spectroscopy (NIRS) is a functional neuroimaging technique that has now been widely utilized in human basic and clinical research. However, its application to animal models has been barely conducted...
October 1, 2016: Behavioural Brain Research
Christa E Osuna, So-Yon Lim, Claire Deleage, Bryan D Griffin, Derek Stein, Lukas T Schroeder, Robert Omage, Katharine Best, Ma Luo, Peter T Hraber, Hanne Andersen-Elyard, Erwing Fabian Cardozo Ojeda, Scott Huang, Dana L Vanlandingham, Stephen Higgs, Alan S Perelson, Jacob D Estes, David Safronetz, Mark G Lewis, James B Whitney
Infection with Zika virus has been associated with serious neurological complications and fetal abnormalities. However, the dynamics of viral infection, replication and shedding are poorly understood. Here we show that both rhesus and cynomolgus macaques are highly susceptible to infection by lineages of Zika virus that are closely related to, or are currently circulating in, the Americas. After subcutaneous viral inoculation, viral RNA was detected in blood plasma as early as 1 d after infection. Viral RNA was also detected in saliva, urine, cerebrospinal fluid (CSF) and semen, but transiently in vaginal secretions...
October 3, 2016: Nature Medicine
Xiling Liu, Dingding Han, Mehmet Somel, Xi Jiang, Haiyang Hu, Patricia Guijarro, Ning Zhang, Amanda Mitchell, Tobias Halene, John J Ely, Chet C Sherwood, Patrick R Hof, Zilong Qiu, Svante Pääbo, Schahram Akbarian, Philipp Khaitovich
Cognitive defects in autism spectrum disorder (ASD) include socialization and communication: key behavioral capacities that separate humans from other species. Here, we analyze gene expression in the prefrontal cortex of 63 autism patients and control individuals, as well as 62 chimpanzees and macaques, from natal to adult age. We show that among all aberrant expression changes seen in ASD brains, a single aberrant expression pattern overrepresented in genes involved synaptic-related pathways is enriched in nucleotide variants linked to autism...
September 2016: PLoS Biology
Kyoko Yoshida, Yasuhiro Go, Itaru Kushima, Atsushi Toyoda, Asao Fujiyama, Hiroo Imai, Nobuhito Saito, Atsushi Iriki, Norio Ozaki, Masaki Isoda
Atypical neurodevelopment in autism spectrum disorder is a mystery, defying explanation despite increasing attention. We report on a Japanese macaque that spontaneously exhibited autistic traits, namely, impaired social ability as well as restricted and repetitive behaviors, along with our single-neuron and genomic analyses. Its social ability was measured in a turn-taking task, where two monkeys monitor each other's actions for adaptive behavioral planning. In its brain, the medial frontal neurons responding to others' actions, abundant in the controls, were almost nonexistent...
September 2016: Science Advances
Lucio Gama, Celina M Abreu, Erin N Shirk, Sarah L Price, Ming Li, Greg M Laird, Kelly A Metcalf Pate, Stephen W Wietgrefe, Shelby L O'connor, Luiz Pianowski, Ashley T Haase, Carine Van Lint, Robert F Siliciano, Janice E Clements, Dummy Authors
OBJECTIVE: Resting CD4+ T cells have been recognized as the major cell reservoir of latent HIV-1 during antiretroviral therapy (ART). Using an SIV/macaque model for AIDS and HIV-related neurocognitive disorders we assessed the contribution of the brain to viral latency and reactivation. DESIGN: Pigtailed macaques were dual inoculated with SIVDeltaB670 and SIV17E-Fr and treated with an efficacious CNS-penetrant ART. After 500 days of viral suppression animals were treated with two cycles of latency reversing agents (LRAs) and increases in viral transcripts were examined...
September 20, 2016: AIDS
Michael Lee, Woong-Ki Kim, Marcelo J Kuroda, Ranajit Pal, Hye Kyung Chung
BACKGROUND: Non-human primates infected with simian immunodeficiency virus (SIV) represent a robust model to evaluate pre-clinical efficacy of HIV-1 preventive strategies and to determine the size of reservoir. METHODS: We developed a real-time qPCR assay to specifically quantify episomal 2-LTR circular DNA in peripheral blood mononuclear cells and brain tissues from SIV-infected macaques. RESULTS: This assay has sensitivity, accuracy and reproducibility over seven orders of magnitude...
October 2016: Journal of Medical Primatology
Barbara L Finlay
The cerebral cortex retains its fundamental organization, layering, and input-output relations as it scales in volume over many orders of magnitude in mammals. How is its network architecture affected by size scaling? By comparing network organization of the mouse and rhesus macaque cortical connectome derived from complete neuroanatomical tracing studies, a recent study in PLOS Biology shows that an exponential distance rule emerges that reveals the falloff in connection probability with distance in the two brains that in turn determines common organizational features...
September 2016: PLoS Biology
Frank Bremmer, Andre Kaminiarz, Steffen Klingenhoefer, Jan Churan
Primates perform saccadic eye movements in order to bring the image of an interesting target onto the fovea. Compared to stationary targets, saccades toward moving targets are computationally more demanding since the oculomotor system must use speed and direction information about the target as well as knowledge about its own processing latency to program an adequate, predictive saccade vector. In monkeys, different brain regions have been implicated in the control of voluntary saccades, among them the lateral intraparietal area (LIP)...
2016: Frontiers in Integrative Neuroscience
Brian E Russ, Takaaki Kaneko, Kadharbatcha S Saleem, Rebecca A Berman, David A Leopold
UNLABELLED: Visual motion responses in the brain are shaped by two distinct sources: the physical movement of objects in the environment and motion resulting from one's own actions. The latter source, termed visual reafference, stems from movements of the head and body, and in primates from the frequent saccadic eye movements that mark natural vision. To study the relative contribution of reafferent and stimulus motion during natural vision, we measured fMRI activity in the brains of two macaques as they freely viewed >50 hours of naturalistic video footage depicting dynamic social interactions...
September 14, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Lisa A Parr, Jenna M Brooks, Trina Jonesteller, Shannon Moss, James O Jordano, Thomas R Heitz
Studies in a variety of species have reported enhanced prosocial effects after an acute administration of the neuromodulating hormone, oxytocin (OT). Although the exact mechanisms underlying these effects are not fully understood, there is broad interest in developing OT into a treatment for social deficits. Only a few studies, however, have examined the effects of OT if given repeatedly during early development, the period when early intervention is likely to have the greatest benefits for reversing the progression towards social impairment...
August 31, 2016: Psychoneuroendocrinology
Brittany D Rife, David J Nolan, Susanna L Lamers, Patrick Autissier, Tricia Burdo, Kenneth C Williams, Marco Salemi
No abstract text is available yet for this article.
October 1, 2016: Journal of Virology
Satoshi Shimegi, Akihiro Kimura, Akinori Sato, Chisa Aoyama, Ryo Mizuyama, Keisuke Tsunoda, Fuyuki Ueda, Sera Araki, Ryoma Goya, Hiromichi Sato
The brain dynamically changes its input-output relationship depending on the behavioral state and context in order to optimize information processing. At the molecular level, cholinergic/monoaminergic transmitters have been extensively studied as key players for the state/context-dependent modulation of brain function. In this paper, we review how cortical visual information processing in the primary visual cortex (V1) of macaque monkey, which has a highly differentiated laminar structure, is optimized by serotonergic and cholinergic systems by examining anatomical and in vivo electrophysiological aspects to highlight their similarities and distinctions...
September 9, 2016: Journal of Physiology, Paris
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"