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1.
PLoS Biol ; 22(1): e3002445, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38163325

ABSTRACT

Serotonin (5-HT) deficiency is a core biological pathology underlying depression and other psychiatric disorders whose key symptoms include decreased motivation. However, the exact role of 5-HT in motivation remains controversial and elusive. Here, we pharmacologically manipulated the 5-HT system in macaque monkeys and quantified the effects on motivation for goal-directed actions in terms of incentives and costs. Reversible inhibition of 5-HT synthesis increased errors and reaction times on goal-directed tasks, indicating reduced motivation. Analysis found incentive-dependent and cost-dependent components of this reduction. To identify the receptor subtypes that mediate cost and incentive, we systemically administered antagonists specific to 4 major 5-HT receptor subtypes: 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT4. Positron emission tomography (PET) visualized the unique distribution of each subtype in limbic brain regions and determined the systemic dosage for antagonists that would achieve approximately 30% occupancy. Only blockade of 5-HT1A decreased motivation through changes in both expected cost and incentive; sensitivity to future workload and time delay to reward increased (cost) and reward value decreased (incentive). Blocking the 5-HT1B receptor also reduced motivation through decreased incentive, although it did not affect expected cost. These results suggest that 5-HT deficiency disrupts 2 processes, the subjective valuation of costs and rewards, via 5-HT1A and 5-HT1B receptors, thus leading to reduced motivation.


Subject(s)
Serotonin Antagonists , Serotonin , Brain/metabolism , Carrier Proteins/metabolism , Receptor, Serotonin, 5-HT1B , Serotonin Antagonists/pharmacology , Macaca , Animals
2.
bioRxiv ; 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38076986

ABSTRACT

To be the most successful, primates must adapt to changing environments and optimize their behavior by making the most beneficial choices. At the core of adaptive behavior is the orbitofrontal cortex (OFC) of the brain, which updates choice value through direct experience or knowledge-based inference. Here, we identify distinct neural circuitry underlying these two separate abilities. We designed two behavioral tasks in which macaque monkeys updated the values of certain items, either by directly experiencing changes in stimulus-reward associations, or by inferring the value of unexperienced items based on the task's rules. Chemogenetic silencing of bilateral OFC combined with mathematical model-fitting analysis revealed that monkey OFC is involved in updating item value based on both experience and inference. In vivo imaging of chemogenetic receptors by positron emission tomography allowed us to map projections from the OFC to the rostromedial caudate nucleus (rmCD) and the medial part of the mediodorsal thalamus (MDm). Chemogenetic silencing of the OFC-rmCD pathway impaired experience-based value updating, while silencing the OFC-MDm pathway impaired inference-based value updating. Our results thus demonstrate a dissociable contribution of distinct OFC projections to different behavioral strategies, and provide new insights into the neural basis of value-based adaptive decision-making in primates.

3.
Biosci Biotechnol Biochem ; 87(12): 1523-1531, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-37709570

ABSTRACT

We focused on Piper longum L., a herbal drug produced in Myanmar, which has a renoprotective effect. Thus, we attempted to isolate and identify compounds that enhance the expression of the ABCG2 gene from the aerial parts of the plant except for the fruit. Among the various P. longum extracts, we isolated and identified the components. Using Caco-2 cells, the hABCG2 mRNA expression-enhancing effects of the isolated compounds were compared with the positive reference compound (3-methylcholanthrene [3MC]) using real-time polymerase chain reaction. Six compounds were isolated and identified from the methanol extract of P. longum. Among the isolated compounds, licarin A and neopomatene had lower toxicity and higher hABCG2 mRNA expression-enhancing effects in Caco-2 cells. Suppression of hAhR expression by siRNA reduced the activity of licarin A and neopomatene, as well as the hAhR agonist 3MC, suggesting that these 2 compounds may act as hAhR agonists to promote hABCG2 expression.


Subject(s)
Lignans , Piper , Humans , Plant Extracts/pharmacology , Caco-2 Cells , Lignans/pharmacology , Gene Expression , RNA, Messenger/genetics , ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics , Neoplasm Proteins
4.
J Neurosci ; 43(39): 6619-6627, 2023 09 27.
Article in English | MEDLINE | ID: mdl-37620158

ABSTRACT

Chemogenetic tools provide an opportunity to manipulate neuronal activity and behavior selectively and repeatedly in nonhuman primates (NHPs) with minimal invasiveness. Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) are one example that is based on mutated muscarinic acetylcholine receptors. Another channel-based chemogenetic system available for neuronal modulation in NHPs uses pharmacologically selective actuator modules (PSAMs), which are selectively activated by pharmacologically selective effector molecules (PSEMs). To facilitate the use of the PSAM/PSEM system, the selection and dosage of PSEMs should be validated and optimized for NHPs. To this end, we used a multimodal imaging approach. We virally expressed excitatory PSAM (PSAM4-5HT3) in the striatum and the primary motor cortex (M1) of two male macaque monkeys, and visualized its location through positron emission tomography (PET) with the reporter ligand [18F]ASEM. Chemogenetic excitability of neurons triggered by two PSEMs (uPSEM817 and uPSEM792) was evaluated using [18F]fluorodeoxyglucose-PET imaging, with uPSEM817 being more efficient than uPSEM792. Pharmacological magnetic resonance imaging (phMRI) showed that increased brain activity in the PSAM4-expressing region began ∼13 min after uPSEM817 administration and continued for at least 60 min. Our multimodal imaging data provide valuable information regarding the manipulation of neuronal activity using the PSAM/PSEM system in NHPs, facilitating future applications.SIGNIFICANCE STATEMENT Like other chemogenetic tools, the ion channel-based system called pharmacologically selective actuator module/pharmacologically selective effector molecule (PSAM/PSEM) allows remote manipulation of neuronal activity and behavior in living animals. Nevertheless, its application in nonhuman primates (NHPs) is still limited. Here, we used multitracer positron emission tomography (PET) imaging and pharmacological magnetic resonance imaging (phMRI) to visualize an excitatory chemogenetic ion channel (PSAM4-5HT3) and validate its chemometric function in macaque monkeys. Our results provide the optimal agonist, dose, and timing for chemogenetic neuronal manipulation, facilitating the use of the PSAM/PSEM system and expanding the flexibility and reliability of circuit manipulation in NHPs in a variety of situations.


Subject(s)
Ion Channels , Primates , Animals , Male , Reproducibility of Results , Multimodal Imaging , Macaca
5.
Neuroimage ; 272: 120035, 2023 05 15.
Article in English | MEDLINE | ID: mdl-36948281

ABSTRACT

The default-mode network (DMN) is a distributed functional brain system integral for social and higher-order cognition in humans with implications in a myriad of neuropsychological disorders. In this study, we compared the functional architecture of the DMN between humans and marmosets to assess their similarities and differences using joint gradients. This approach permits simultaneous large-scale mapping of functional systems across the cortex of humans and marmosets, revealing evidence of putative homologies between them. In doing so, we find that the DMN architecture of the marmoset exhibits differences along its anterolateral-posterior axis. Specifically, the anterolateral node of the DMN (dorsolateral prefrontal cortex) displayed weak connections and inconsistent connection topographies as compared to its posterior DMN-nodes (posterior cingulate and posterior parietal cortices). We also present evidence that the marmoset medial prefrontal cortex and temporal lobe areas correspond to other macroscopical distributed functional systems that are not part of the DMN. Given the importance of the marmoset as a pre-clinical primate model for higher-order cognitive functioning and the DMN's relevance to cognition, our results suggest that the marmoset may lack the capacity to integrate neural information to subserve cortical dynamics that are necessary for supporting diverse cognitive demands.


Subject(s)
Brain Mapping , Callithrix , Animals , Humans , Brain Mapping/methods , Default Mode Network , Magnetic Resonance Imaging/methods , Brain , Neural Pathways
6.
Drug Metab Pharmacokinet ; 50: 100499, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36907086

ABSTRACT

Understanding the physiological effects of food ingredients on bodily functions is crucial for the development of foods for specified health use (FoSHU) and functional foods. To investigate this, intestinal epithelial cells (IECs) have been widely studied as they are most frequently exposed to the highest concentrations of food ingredients. Among the various functions of IECs, in this review, we have discussed glucose transporters and their involvement in preventing metabolic syndromes such as diabetes. Phytochemicals are also discussed, as they significantly inhibit glucose and fructose absorption via sodium-dependent glucose transporter 1 (SGLT1) and glucose transporter 5 (GLUT5), respectively. Additionally, we have focused on the barrier functions of IECs against xenobiotics. Phytochemicals induce detoxification of metabolizing enzymes via pregnane X receptor or aryl hydrocarbon receptor activation, which suggests that food ingredients can enhance barrier function. This review will provide insights into the role of food ingredients and glucose transporters, as well as detoxification metabolizing enzymes in IECs, and help guide future research on these aspects.


Subject(s)
Food Ingredients , Intestines , Epithelial Cells/metabolism , Glucose/metabolism , Glucose/pharmacology
7.
JBJS Case Connect ; 13(1)2023 01 01.
Article in English | MEDLINE | ID: mdl-36656996

ABSTRACT

CASE: A 76-year-old woman presented with a 2-month history of right shoulder pain with no apparent cause. Radiography revealed an ill-defined osteolytic lesion in the right scapular spine with a pathological fracture. Malignant bone tumor was suspected, and a biopsy was performed. Pathological examination with gold hydroxamic acid staining revealed phosphoglyceride crystal deposition. Lesion curettage was performed, and her symptoms improved. No recurrence was observed at the 3-year postoperative follow-up. CONCLUSION: Phosphoglyceride crystal deposition in the bone is an extremely rare disease. The gold hydroxamic acid staining method might be useful for the diagnosis of this condition.


Subject(s)
Bone Neoplasms , Glycerophospholipids , Female , Humans , Aged , Scapula/diagnostic imaging , Scapula/pathology , Radiography , Shoulder Pain/etiology , Bone Neoplasms/pathology
8.
J Neurosci ; 42(32): 6267-6275, 2022 08 10.
Article in English | MEDLINE | ID: mdl-35794012

ABSTRACT

The orbitofrontal cortex (OFC) and its major downstream target within the basal ganglia-the rostromedial caudate nucleus (rmCD)-are involved in reward-value processing and goal-directed behavior. However, a causal contribution of the pathway linking these two structures to goal-directed behavior has not been established. Using the chemogenetic technology of designer receptors exclusively activated by designer drugs with a crossed inactivation design, we functionally and reversibly disrupted interactions between the OFC and rmCD in two male macaque monkeys. We injected an adeno-associated virus vector expressing an inhibitory designer receptor, hM4Di, into the OFC and contralateral rmCD, the expression of which was visualized in vivo by positron emission tomography and confirmed by postmortem immunohistochemistry. Functional disconnection of the OFC and rmCD resulted in a significant and reproducible loss of sensitivity to the cued reward value for goal-directed action. This decreased sensitivity was most prominent when monkeys had accumulated a certain amount of reward. These results provide causal evidence that the interaction between the OFC and the rmCD is needed for motivational control of action on the basis of the relative reward value and internal drive. This finding extends the current understanding of the physiological basis of psychiatric disorders in which goal-directed behavior is affected, such as obsessive-compulsive disorder.SIGNIFICANCE STATEMENT In daily life, we routinely adjust the speed and accuracy of our actions on the basis of the value of expected reward. Abnormalities in these kinds of motivational adjustments might be related to behaviors seen in psychiatric disorders such as obsessive-compulsive disorder. In the current study, we show that the connection from the orbitofrontal cortex to the rostromedial caudate nucleus is essential for motivational control of action in monkeys. This finding expands our knowledge about how the primate brain controls motivation and behavior and provides a particular insight into disorders like obsessive-compulsive disorder in which altered connectivity between the orbitofrontal cortex and the striatum has been implicated.


Subject(s)
Caudate Nucleus , Motivation , Animals , Caudate Nucleus/physiology , Goals , Humans , Male , Prefrontal Cortex/physiology , Reward
9.
Cell Rep ; 39(2): 110669, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35417698

ABSTRACT

The human default mode network (DMN) is engaged at rest and in cognitive states such as self-directed thoughts. Interconnected homologous cortical areas in primates constitute a network considered as the equivalent. Here, based on a cross-species comparison of the DMN between humans and non-hominoid primates (macaques, marmosets, and mouse lemurs), we report major dissimilarities in connectivity profiles. Most importantly, the medial prefrontal cortex (mPFC) of non-hominoid primates is poorly engaged with the posterior cingulate cortex (PCC), though strong correlated activity between the human PCC and the mPFC is a key feature of the human DMN. Instead, a fronto-temporal resting-state network involving the mPFC was detected consistently across non-hominoid primate species. These common functional features shared between non-hominoid primates but not with humans suggest a substantial gap in the organization of the primate's DMN and its associated cognitive functions.


Subject(s)
Brain Mapping , Brain , Animals , Callithrix , Default Mode Network , Magnetic Resonance Imaging , Neural Pathways
10.
J Pharm Health Care Sci ; 8(1): 5, 2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35105386

ABSTRACT

BACKGROUND: Gemcitabine plus nab-paclitaxel (GnP) therapy is used for unresectable pancreatic ductal adenocarcinoma, but may cause interstitial lung disease (ILD) as a serious side effect. However, the risk factors for ILD in patients receiving GnP therapy are not well established. Here, we retrospectively investigated the incidence of GnP-induced ILD in pancreatic ductal adenocarcinoma patients, and the risk factors. METHODS: We investigated the patients' background, laboratory data, previous treatment history, concomitant medications, number of doses of GnP, cumulative dosage and administration period, and occurrence of side effects. RESULTS: Of the 105 patients included in this study, ILD occurred in 10 (9.5%). Patients with ILD had a significantly higher frequency of concomitant treatment with Kampo medicines, especially goshajinkigan, which is considered to help prevent chemotherapy-induced peripheral neuropathy (CIPN) (odds ratio: 11.5, 95% confidence interval: 2.67-49.38). No significant differences were observed in other clinical characteristics. Notably, the severity of CIPN in patients who used goshajinkigan for prevention was not significantly different from that in patients who did not use goshajinkigan in this study. CONCLUSIONS: These results suggest that administration of goshajinkigan to patients receiving GnP therapy for prevention of CIPN may need to be reconsidered.

11.
Neuroimage ; 252: 119030, 2022 05 15.
Article in English | MEDLINE | ID: mdl-35217206

ABSTRACT

The common marmoset (Callithrix jacchus) is quickly gaining traction as a premier neuroscientific model. However, considerable progress is still needed in understanding the functional and structural organization of the marmoset brain to rival that documented in longstanding preclinical model species, like mice, rats, and Old World primates. To accelerate such progress, we present the Marmoset Functional Brain Connectivity Resource (marmosetbrainconnectome.org), currently consisting of over 70 h of resting-state fMRI (RS-fMRI) data acquired at 500 µm isotropic resolution from 31 fully awake marmosets in a common stereotactic space. Three-dimensional functional connectivity (FC) maps for every cortical and subcortical gray matter voxel are stored online. Users can instantaneously view, manipulate, and download any whole-brain functional connectivity (FC) topology (at the subject- or group-level) along with the raw datasets and preprocessing code. Importantly, researchers can use this resource to test hypotheses about FC directly - with no additional analyses required - yielding whole-brain correlations for any gray matter voxel on demand. We demonstrate the resource's utility for presurgical planning and comparison with tracer-based neuronal connectivity as proof of concept. Complementing existing structural connectivity resources for the marmoset brain, the Marmoset Functional Brain Connectivity Resource affords users the distinct advantage of exploring the connectivity of any voxel in the marmoset brain, not limited to injection sites nor constrained by regional atlases. With the entire raw database (RS-fMRI and structural images) and preprocessing code openly available for download and use, we expect this resource to be broadly valuable to test novel hypotheses about the functional organization of the marmoset brain.


Subject(s)
Callithrix , Wakefulness , Access to Information , Animals , Brain/physiology , Callithrix/physiology , Humans , Magnetic Resonance Imaging/methods , Mice , Rats
12.
Neuroimage ; 250: 118965, 2022 04 15.
Article in English | MEDLINE | ID: mdl-35122965

ABSTRACT

Localising accurate brain regions needs careful evaluation in each experimental species due to their individual variability. However, the function and connectivity of brain areas is commonly studied using a single-subject cranial landmark-based stereotactic atlas in animal neuroscience. Here, we address this issue in a small primate, the common marmoset, which is increasingly widely used in systems neuroscience. We developed a non-invasive multi-modal neuroimaging-based targeting pipeline, which accounts for intersubject anatomical variability in cranial and cortical landmarks in marmosets. This methodology allowed creation of multi-modal templates (MarmosetRIKEN20) including head CT and brain MR images, embedded in coordinate systems of anterior and posterior commissures (AC-PC) and CIFTI grayordinates. We found that the horizontal plane of the stereotactic coordinate was significantly rotated in pitch relative to the AC-PC coordinate system (10 degrees, frontal downwards), and had a significant bias and uncertainty due to positioning procedures. We also found that many common cranial and brain landmarks (e.g., bregma, intraparietal sulcus) vary in location across subjects and are substantial relative to average marmoset cortical area dimensions. Combining the neuroimaging-based targeting pipeline with robot-guided surgery enabled proof-of-concept targeting of deep brain structures with an accuracy of 0.2 mm. Altogether, our findings demonstrate substantial intersubject variability in marmoset brain and cranial landmarks, implying that subject-specific neuroimaging-based localization is needed for precision targeting in marmosets. The population-based templates and atlases in grayordinates, created for the first time in marmoset monkeys, should help bridging between macroscale and microscale analyses.


Subject(s)
Brain Mapping/methods , Brain/anatomy & histology , Callithrix/anatomy & histology , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Anatomic Landmarks , Animals , Brain/surgery , Callithrix/surgery , Equipment Design , Image Processing, Computer-Assisted , Magnetic Resonance Imaging/instrumentation , Reproducibility of Results , Surgery, Computer-Assisted , Tomography, X-Ray Computed/instrumentation
13.
Cereb Cortex ; 32(9): 1965-1977, 2022 04 20.
Article in English | MEDLINE | ID: mdl-34515315

ABSTRACT

Frontoparietal networks contribute to complex cognitive functions in humans and macaques, such as working memory, attention, task-switching, response suppression, grasping, reaching, and eye movement control. However, there has been no comprehensive examination of the functional organization of frontoparietal networks using functional magnetic resonance imaging in the New World common marmoset monkey (Callithrix jacchus), which is now widely recognized as a powerful nonhuman primate experimental animal. In this study, we employed hierarchical clustering of interareal blood oxygen level-dependent signals to investigate the hypothesis that the organization of the frontoparietal cortex in the marmoset follows the organizational principles of the macaque frontoparietal system. We found that the posterior part of the lateral frontal cortex (premotor regions) was functionally connected to the anterior parietal areas, while more anterior frontal regions (frontal eye field [FEF]) were connected to more posterior parietal areas (the region around the lateral intraparietal area [LIP]). These overarching patterns of interareal organization are consistent with a recent macaque study. These findings demonstrate parallel frontoparietal processing streams in marmosets and support the functional similarities of FEF-LIP and premotor-anterior parietal pathways between marmoset and macaque.


Subject(s)
Callithrix , Magnetic Resonance Imaging , Animals , Brain Mapping , Callithrix/physiology , Cerebral Cortex , Frontal Lobe/diagnostic imaging , Frontal Lobe/physiology , Macaca , Wakefulness
14.
Gen Thorac Cardiovasc Surg ; 70(5): 419-429, 2022 May.
Article in English | MEDLINE | ID: mdl-34613579

ABSTRACT

OBJECTIVE: We assessed the clinical effectiveness of coronary artery bypass grafting (CABG) in comparison with that of percutaneous coronary intervention (PCI) in octogenarians with triple-vessel disease (TVD) or left main coronary artery (LMCA) disease. METHODS: From the CREDO-Kyoto registry cohort-2, 527 patients, who were ≥ 80 years of age and underwent the first coronary revascularization for TVD or LMCA disease, were divided into the CABG group (N = 151) and the PCI group (N = 376). RESULTS: The median and interquartile range of patient's age was 82 (81-84) in the CABG group and 83 (81-85) in the PCI group (P = 0.10). Patients > = 85 years of age accounted for 19% and 31% in the CABG and PCI groups, respectively (P = 0.01). The cumulative 5-year incidence of all-cause death was similar between CABG and PCI groups (35.8% vs. 42.9%, log-rank P = 0.18), while CABG showed a lower rate of the composite of cardiac death/MI than PCI (21.7% vs. 33.9%, log-rank P = 0.005). After adjusting for confounders, the lower risk of CABG relative to PCI was significant for all-cause death (HR 0.61, 95% CI 0.43-0.86, P = 0.005), any coronary revascularization (HR 0.25, 95% CI 0.14-0.43, P < 0.001) and the composite of cardiac death/MI (HR 0.52, 95% CI 0.32-0.85, P = 0.009). CONCLUSIONS: CABG compared with PCI was associated with a lower adjusted risk for all-cause death, any coronary revascularization, and a composite of cardiac death/MI in very elderly patients with TVD or LMCA disease. CABG seemed an acceptable option for selected octogenarians with severe coronary artery disease.


Subject(s)
Coronary Artery Disease , Drug-Eluting Stents , Myocardial Infarction , Percutaneous Coronary Intervention , Stroke , Aged , Aged, 80 and over , Coronary Artery Bypass/adverse effects , Coronary Artery Disease/surgery , Death , Humans , Octogenarians , Percutaneous Coronary Intervention/adverse effects , Stroke/epidemiology , Treatment Outcome
15.
Nat Commun ; 12(1): 6608, 2021 11 16.
Article in English | MEDLINE | ID: mdl-34785685

ABSTRACT

Social cognition is a dynamic process that requires the perception and integration of a complex set of idiosyncratic features between interacting conspecifics. Here we present a method for simultaneously measuring the whole-brain activation of two socially interacting marmoset monkeys using functional magnetic resonance imaging. MRI hardware (a radiofrequency coil and peripheral devices) and image-processing pipelines were developed to assess brain responses to socialization, both on an intra-brain and inter-brain level. Notably, the brain activation of a marmoset when viewing a second marmoset in-person versus when viewing a pre-recorded video of the same marmoset-i.e., when either capable or incapable of socially interacting with a visible conspecific-demonstrates increased activation in the face-patch network. This method enables a wide range of possibilities for potentially studying social function and dysfunction in a non-human primate model.


Subject(s)
Brain/physiology , Callithrix/physiology , Magnetic Resonance Imaging/methods , Wakefulness , Animals , Brain/diagnostic imaging , Brain Mapping , Cognitive Neuroscience , Face , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging/instrumentation , Male
16.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Article in English | MEDLINE | ID: mdl-34493677

ABSTRACT

The common marmoset has enormous promise as a nonhuman primate model of human brain functions. While resting-state functional MRI (fMRI) has provided evidence for a similar organization of marmoset and human cortices, the technique cannot be used to map the functional correspondences of brain regions between species. This limitation can be overcome by movie-driven fMRI (md-fMRI), which has become a popular tool for noninvasively mapping the neural patterns generated by rich and naturalistic stimulation. Here, we used md-fMRI in marmosets and humans to identify whole-brain functional correspondences between the two primate species. In particular, we describe functional correlates for the well-known human face, body, and scene patches in marmosets. We find that these networks have a similar organization in both species, suggesting a largely conserved organization of higher-order visual areas between New World marmoset monkeys and humans. However, while face patches in humans and marmosets were activated by marmoset faces, only human face patches responded to the faces of other animals. Together, the results demonstrate that higher-order visual processing might be a conserved feature between humans and New World marmoset monkeys but that small, potentially important functional differences exist.


Subject(s)
Brain Mapping/methods , Brain/physiology , Callithrix/physiology , Face/physiology , Magnetic Resonance Imaging/methods , Neural Pathways , Visual Perception/physiology , Adult , Animals , Brain/anatomy & histology , Face/anatomy & histology , Female , Humans , Male , Middle Aged , Young Adult
17.
Elife ; 102021 03 31.
Article in English | MEDLINE | ID: mdl-33787492

ABSTRACT

A crucial component of social cognition is to observe and understand the social interactions of other individuals. A promising nonhuman primate model for investigating the neural basis of social interaction observation is the common marmoset (Callithrix jacchus), a small New World primate that shares a rich social repertoire with humans. Here, we used functional magnetic resonance imaging acquired at 9.4 T to map the brain areas activated by social interaction observation in awake marmosets. We discovered a network of subcortical and cortical areas, predominately in the anterior lateral frontal and medial frontal cortex, that was specifically activated by social interaction observation. This network resembled that recently identified in Old World macaque monkeys. Our findings suggest that this network is largely conserved between New and Old World primates and support the use of marmosets for studying the neural basis of social cognition.


Subject(s)
Brain Mapping , Callithrix/physiology , Magnetic Resonance Imaging , Nerve Net/diagnostic imaging , Social Interaction , Animals , Callithrix/anatomy & histology , Female , Male , Models, Animal
18.
Macromol Rapid Commun ; 42(8): e2000577, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33251648

ABSTRACT

Polymer-graphene composites have attracted significant attention; however, their formation mechanisms are a focus of debate. This work tries to clarify how grafting occurs on graphene by electron spin resonance techniques. As a result, two pathways are found. One passes through the radicals formed by cleaving CO bonds on graphene are transferred to monomers, then grafting and polymerization proceed. Another mechanism passes through the oxy-radicals, which react with monomers in solution and finally react with carbon radicals on graphene. Based on the mechanism, various types of polymer-graphene composites are prepared, and applied to electrical conductive sheets, basic catalysts, and acidic catalysts.


Subject(s)
Graphite , Electric Conductivity , Macromolecular Substances , Polymerization , Polymers
19.
J Neurophysiol ; 124(6): 1900-1913, 2020 12 01.
Article in English | MEDLINE | ID: mdl-33112698

ABSTRACT

The common marmoset (Callithrix jacchus) is a small-bodied New World primate that is becoming an important model to study brain functions. Despite several studies exploring the somatosensory system of marmosets, all results have come from anesthetized animals using invasive techniques and postmortem analyses. Here, we demonstrate the feasibility for getting high-quality and reproducible somatosensory mapping in awake marmosets with functional magnetic resonance imaging (fMRI). We acquired fMRI sequences in four animals, while they received tactile stimulation (via air-puffs), delivered to the face, arm, or leg. We found a topographic body representation with the leg representation in the most medial part, the face representation in the most lateral part, and the arm representation between leg and face representation within areas 3a, 3b, and 1/2. A similar sequence from leg to face from caudal to rostral sites was identified in areas S2 and PV. By generating functional connectivity maps of seeds defined in the primary and second somatosensory regions, we identified two clusters of tactile representation within the posterior and midcingulate cortex. However, unlike humans and macaques, no clear somatotopic maps were observed. At the subcortical level, we found a somatotopic body representation in the thalamus and, for the first time in marmosets, in the putamen. These maps have similar organizations, as those previously found in Old World macaque monkeys and humans, suggesting that these subcortical somatotopic organizations were already established before Old and New World primates diverged. Our results show the first whole brain mapping of somatosensory responses acquired in a noninvasive way in awake marmosets.NEW & NOTEWORTHY We used somatosensory stimulation combined with functional MRI (fMRI) in awake marmosets to reveal the topographic body representation in areas S1, S2, thalamus, and putamen. We showed the existence of a body representation organization within the thalamus and the cingulate cortex by computing functional connectivity maps from seeds defined in S1/S2, using resting-state fMRI data. This noninvasive approach will be essential for chronic studies by guiding invasive recording and manipulation techniques.


Subject(s)
Brain Mapping , Gyrus Cinguli/physiology , Putamen/physiology , Somatosensory Cortex/physiology , Thalamus/physiology , Touch Perception/physiology , Animals , Arm , Behavior, Animal/physiology , Callithrix , Connectome , Face , Female , Gyrus Cinguli/diagnostic imaging , Leg , Magnetic Resonance Imaging , Male , Physical Stimulation , Putamen/diagnostic imaging , Somatosensory Cortex/diagnostic imaging , Thalamus/diagnostic imaging
20.
J Neurosci ; 40(48): 9236-9249, 2020 11 25.
Article in English | MEDLINE | ID: mdl-33097633

ABSTRACT

Understanding the similarity of cortico-subcortical networks topologies between humans and nonhuman primate species is critical to study the origin of network alternations underlying human neurologic and neuropsychiatric diseases. The New World common marmoset (Callithrix jacchus) has become popular as a nonhuman primate model for human brain function. Most marmoset connectomic research, however, has exclusively focused on cortical areas, with connectivity to subcortical networks less extensively explored. Here, we aimed to first isolate patterns of subcortical connectivity with cortical resting-state networks in awake marmosets using resting-state fMRI, then to compare these networks with those in humans using connectivity fingerprinting. In this study, we used 5 marmosets (4 males, 1 female). While we could match several marmoset and human resting-state networks based on their functional fingerprints, we also found a few striking differences, for example, strong functional connectivity of the default mode network with the superior colliculus in marmosets that was much weaker in humans. Together, these findings demonstrate that many of the core cortico-subcortical networks in humans are also present in marmosets, but that small, potentially functionally relevant differences exist.SIGNIFICANCE STATEMENT The common marmoset is becoming increasingly popular as an additional preclinical nonhuman primate model for human brain function. Here we compared the functional organization of cortico-subcortical networks in marmosets and humans using ultra-high field fMRI. We isolated the patterns of subcortical connectivity with cortical resting-state networks (RSNs) in awake marmosets using resting-state fMRI and then compared these networks with those in humans using connectivity fingerprinting. While we could match several marmoset and human RSNs based on their functional fingerprints, we also found several striking differences. Together, these findings demonstrate that many of the core cortico-subcortical RSNs in humans are also present in marmosets, but that small, potentially functionally relevant differences exist.


Subject(s)
Cerebral Cortex/physiology , Neural Pathways/physiology , Animals , Callithrix , Cerebral Cortex/diagnostic imaging , Connectome , Female , Humans , Magnetic Resonance Imaging , Male , Neural Pathways/diagnostic imaging , Rest/physiology , Species Specificity , Superior Colliculi/physiology
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