1,625 results on '"*TUPAIIDAE"'
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2. Morphology, genetic characterization and phylogeny of Moniliformis tupaia n. sp. (Acanthocephala: Moniliformidae) from the northern tree shrew Tupaia belangeri chinensis Anderson (Mammalia: Scandentia).
- Author
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Chen, Hui-Xia, Yu, Zhi-Jun, Ma, Jun, Zhao, Cui-Hong, Cao, Fu-Qiong, and Li, Liang
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ACANTHOCEPHALA ,PHYLOGENY ,SHREWS ,MAMMALS ,MORPHOLOGY - Abstract
A new species of Moniliformis , M. tupaia n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analysing the nuclear 18S, ITS, 28S regions and mitochondrial cox 1 and cox 2 genes), based on specimens collected from the intestine of the northern tree shrew Tupaia belangeri chinensis Anderson (Scandentia: Tupaiidae) in China. Phylogenetic analyses show that M. tupaia n. sp. is a sister to M. moniliformis in the genus Moniliformis , and also challenge the systematic status of Nephridiacanthus major. Moniliformis tupaia n. sp. represents the third Moniliformis species reported from China. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Identification of cytochrome P450 2C18 and 2C76 in tree shrews: P450 2C18 effectively oxidizes typical human P450 2C9/2C19 chiral substrates warfarin and omeprazole with less stereoselectivity.
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Uno Y, Minami Y, Tsukiyama-Kohara K, Murayama N, and Yamazaki H
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- Animals, Humans, Amino Acid Sequence, Substrate Specificity, Stereoisomerism, Cytochrome P-450 CYP2C19 metabolism, Cytochrome P-450 CYP2C19 genetics, Aryl Hydrocarbon Hydroxylases metabolism, Aryl Hydrocarbon Hydroxylases genetics, Oxidation-Reduction, Microsomes, Liver metabolism, Omeprazole metabolism, Tupaiidae, Cytochrome P-450 Enzyme System metabolism, Cytochrome P-450 Enzyme System genetics, Warfarin metabolism, Cytochrome P-450 CYP2C9 metabolism, Cytochrome P-450 CYP2C9 genetics, Phylogeny
- Abstract
Cytochromes P450 (P450s or CYPs), especially the CYP2C family, are important drug-metabolizing enzymes that play major roles in drug metabolism. Tree shrews, a non-rodent primate-like species, are used in various fields of biomedical research, notably hepatitis virus infection; however, its drug-metabolizing enzymes have not been fully investigated. In this study, tree shrew CYP2C18, CYP2C76a, CYP2C76b, and CYP2C76c cDNAs were identified and contained open reading frames of 489 or 490 amino acids with high sequence identities (70-78 %) to human CYP2Cs. Tree shrew CYP2C76a, CYP2C76b, and CYP2C76c showed higher sequence identities (79-80 %) to cynomolgus CYP2C76 and were not orthologous to any human CYP2C. Phylogenetic analysis revealed that tree shrew CYP2C18 and CYP2C76s were closely related to rat CYP2Cs and cynomolgus CYP2C76, respectively. Tree shrew CYP2C genes formed a gene cluster similar to human CYP2C genes. All four tree shrew CYP2C mRNAs showed predominant expressions in liver, among the tissue types examined; expression of CYP2C18 mRNA was also detected in small intestine. In liver, CYP2C18 mRNA was the most abundant among the tree shrew CYP2C mRNAs. In metabolic assays using human CYP2C substrates, all tree shrew CYP2Cs showed metabolic activities toward diclofenac, R,S-omeprazole, paclitaxel, and R,S-warfarin, with the activity of CYP2C18 exceeding that of the other CYP2Cs. Moreover, tree shrew CYP2C76 enzymes metabolized progesterone more efficiently than human, cynomolgus, or marmoset CYP2Cs. Therefore, these novel tree shrew CYP2Cs are expressed abundantly in liver, encode functional enzymes that metabolize human CYP2C substrates, and are likely responsible for drug clearances., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)
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- 2024
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4. Biomechanical changes of tree shrew posterior sclera during experimental myopia, after retrobulbar vehicle injections, and crosslinking using genipin.
- Author
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Bianco G, Girkin CA, Samuels BC, Fazio MA, and Grytz R
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- Animals, Biomechanical Phenomena drug effects, Cross-Linking Reagents, Collagen metabolism, Sclera drug effects, Sclera metabolism, Iridoids pharmacology, Iridoids administration & dosage, Myopia drug therapy, Myopia physiopathology, Tupaiidae, Disease Models, Animal
- Abstract
Myopia is a common ocular condition characterized by biomechanical weakening revealed by increasing creep rate, cyclic softening scleral thinning, change of collagen fibril crimping, and excessive elongation of the posterior sclera resulting in blurred vision. Animal studies support scleral crosslinking as a potential treatment for myopia control by strengthening the weakened sclera and slowing scleral expansion. While multiple studies investigated aspects of the biomechanical weakening and strengthening effects in myopia and after scleral crosslinking, a comprehensive analysis of the underlying mechanical changes including the effect of vehicle injections is still missing. The purpose of this study was to provide a comprehensive analysis of biomechanical changes by scleral inflation testing in experimental myopia, after retrobulbar vehicle injections and scleral crosslinking using genipin in tree shrews. Our results suggest that biomechanical weakening in myopia involves an increased creep rate and higher strain levels at which collagen fibers uncrimp. Both weakening effects were reduced after scleral crosslinking using genipin at doses that were effective in slowing myopia progression. Vehicle injections increased mechanical hysteresis and had a small but significant effect on slowing myopia progression. Also, our results support scleral crosslinking as a potential treatment modality that can prevent or counteract scleral weakening effects in myopia. Furthermore, vehicle solutions may cause independent biomechanical effects, which should be considered when developing and evaluating scleral crosslinking procedures., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)
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- 2024
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5. Visible-Light Optical Coherence Tomography Fibergraphy of the Tree Shrew Retinal Ganglion Cell Axon Bundles.
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Miller DA, Grannonico M, Liu M, Savier E, McHaney K, Erisir A, Netland PA, Cang J, Liu X, and Zhang HF
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- Animals, Tomography, Optical Coherence methods, Retinal Ganglion Cells cytology, Axons physiology, Tupaiidae
- Abstract
We seek to develop techniques for high-resolution imaging of the tree shrew retina for visualizing and parameterizing retinal ganglion cell (RGC) axon bundles in vivo. We applied visible-light optical coherence tomography fibergraphy (vis-OCTF) and temporal speckle averaging (TSA) to visualize individual RGC axon bundles in the tree shrew retina. For the first time, we quantified individual RGC bundle width, height, and cross-sectional area and applied vis-OCT angiography (vis-OCTA) to visualize the retinal microvasculature in tree shrews. Throughout the retina, as the distance from the optic nerve head (ONH) increased from 0.5 mm to 2.5 mm, bundle width increased by 30%, height decreased by 67%, and cross-sectional area decreased by 36%. We also showed that axon bundles become vertically elongated as they converge toward the ONH. Ex vivo confocal microscopy of retinal flat-mounts immunostained with Tuj1 confirmed our in vivo vis-OCTF findings.
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- 2024
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6. Intracortical Microstimulation Maps of Motor, Somatosensory, and Posterior Parietal Cortex in Tree Shrews ( Tupaia belangeri ) Reveal Complex Movement Representations
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Baldwin, Mary KL, Cooke, Dylan F, and Krubitzer, Leah
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Biomedical and Clinical Sciences ,Biological Psychology ,Cognitive and Computational Psychology ,Neurosciences ,Psychology ,Animals ,Brain Mapping ,Electric Stimulation ,Extremities ,Face ,Female ,Motor Cortex ,Movement ,Neural Pathways ,Parietal Lobe ,Somatosensory Cortex ,Tupaiidae ,evolution ,grasping ,motor cortex ,primate ,reaching ,Cognitive Sciences ,Experimental Psychology ,Biological psychology ,Cognitive and computational psychology - Abstract
Long-train intracortical microstimulation (LT-ICMS) is a popular method for studying the organization of motor and posterior parietal cortex (PPC) in mammals. In primates, LT-ICMS evokes both multijoint and multiple-body-part movements in primary motor, premotor, and PPC. In rodents, LT-ICMS evokes complex movements of a single limb in motor cortex. Unfortunately, very little is known about motor/PPC organization in other mammals. Tree shrews are closely related to both primates and rodents and could provide insights into the evolution of complex movement domains in primates. The present study investigated the extent of cortex in which movements could be evoked with ICMS and the characteristics of movements elicited using both short train (ST) and LT-ICMS in tree shrews. We demonstrate that LT-ICMS and ST-ICMS maps are similar, with the movements elicited with ST-ICMS being truncated versions of those elicited with LT-ICMS. In addition, LT-ICMS-evoked complex movements within motor cortex similar to those in rodents. More complex movements involving multiple body parts such as the hand and mouth were also elicited in motor cortex and PPC, as in primates. Our results suggest that complex movement networks present in PPC and motor cortex were present in mammals prior to the emergence of primates.
- Published
- 2017
7. Neutralizing monoclonal antibodies protect against human adenovirus type 55 infection in transgenic mice and tree shrews.
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Liu X, Li Z, Li X, Zhang X, Zheng Y, Su W, Feng Y, Liu Y, Wu W, Sun X, Wang N, Ye X, Zhou Z, Liu W, He J, Wang W, Qu L, Zhou R, Chen L, and Feng L
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- Mice, Animals, Humans, Antibodies, Neutralizing, Mice, Transgenic, Antibodies, Viral, Tupaia, Macaca mulatta, Antibodies, Monoclonal, Tupaiidae, Viral Proteins, Adenoviruses, Human genetics, Pneumonia
- Abstract
Re-emerging human adenovirus type 55 (HAdV55) has become a significant threat to public health due to its widespread circulation and the association with severe pneumonia, but an effective anti-HAdV55 agent remains unavailable. Herein, we report the generation of macaque-derived, human-like monoclonal antibodies (mAbs) protecting against HAdV55 infection with high potency. Using fluorophore-labelled HAdV55 virions as probes, we isolated specific memory B cells from rhesus macaques ( Macaca mulatta ) that were immunized twice with an experimental vaccine based on E1-, E3-deleted, replication-incompetent HAdV55. We cloned a total of 19 neutralizing mAbs, nine of which showed half-maximal inhibitory concentrations below 1.0 ng/ml. These mAbs recognized the hyper-variable-region (HVR) 1, 2, or 7 of viral hexon protein, or the fibre knob. In transgenic mice expressing human desmoglein-2, the major cellular receptor for HAdV55, a single intraperitoneal injection with hexon-targeting mAbs efficiently prevented HAdV55 infection, and mAb 29C12 showed protection at a dose as low as 0.004 mg/kg. Fibre-targeting mAb 28E8, however, showed protection only at a dose up to 12.5 mg/kg. In tree shrews that are permissive for HAdV55 infection and disease, mAb 29C12 effectively prevented HAdV55-caused pneumonia. Further analysis revealed that fibre-targeting mAbs blocked the attachment of HAdV55 to host cells, whereas hexon-targeting mAbs, regardless of their targeting HVRs, mainly functioned at post-attachment stage via inhibiting viral endosomal escape. Our results indicate that hexon-targeting mAbs have great anti-HAdV55 activities and warrant pre-clinical and clinical evaluation.
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- 2024
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8. Study of tree shrew biology and models: A booming and prosperous field for biomedical research.
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Yao YG, Lu L, Ni RJ, Bi R, Chen C, Chen JQ, Fuchs E, Gorbatyuk M, Lei H, Li H, Liu C, Lv LB, Tsukiyama-Kohara K, Kohara M, Perez-Cruz C, Rainer G, Shan BC, Shen F, Tang AZ, Wang J, Xia W, Xia X, Xu L, Yu D, Zhang F, Zheng P, Zheng YT, Zhou J, and Zhou JN
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- Animals, Tupaiidae, Disease Models, Animal, Tupaia, Models, Animal, Biomedical Research trends
- Abstract
The tree shrew ( Tupaia belangeri ) has long been proposed as a suitable alternative to non-human primates (NHPs) in biomedical and laboratory research due to its close evolutionary relationship with primates. In recent years, significant advances have facilitated tree shrew studies, including the determination of the tree shrew genome, genetic manipulation using spermatogonial stem cells, viral vector-mediated gene delivery, and mapping of the tree shrew brain atlas. However, the limited availability of tree shrews globally remains a substantial challenge in the field. Additionally, determining the key questions best answered using tree shrews constitutes another difficulty. Tree shrew models have historically been used to study hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, myopia, and psychosocial stress-induced depression, with more recent studies focusing on developing animal models for infectious and neurodegenerative diseases. Despite these efforts, the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical research. This review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this model. We emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew studies. The use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models, meeting the increasing demands of life science and biomedical research.
- Published
- 2024
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9. Human-like adrenal features in Chinese tree shrews revealed by multi-omics analysis of adrenal cell populations and steroid synthesis.
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Jiang JH, Wang YF, Zheng J, Lei YM, Chen ZY, Guo Y, Guo YJ, Guo BQ, Lv YF, Wang HH, Xie JJ, Liu YX, Jin TW, Li BQ, Zhu XS, Jiang YH, and Mo ZN
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- Animals, Humans, Transcriptome, Mice, Tupaiidae, Female, Multiomics, Adrenal Glands metabolism, Steroids biosynthesis, Steroids metabolism
- Abstract
The Chinese tree shrew ( Tupaia belangeri chinensis ) has emerged as a promising model for investigating adrenal steroid synthesis, but it is unclear whether the same cells produce steroid hormones and whether their production is regulated in the same way as in humans. Here, we comprehensively mapped the cell types and pathways of steroid metabolism in the adrenal gland of Chinese tree shrews using single-cell RNA sequencing, spatial transcriptome analysis, mass spectrometry, and immunohistochemistry. We compared the transcriptomes of various adrenal cell types across tree shrews, humans, macaques, and mice. Results showed that tree shrew adrenal glands expressed many of the same key enzymes for steroid synthesis as humans, including CYP11B2 , CYP11B1 , CYB5A , and CHGA . Biochemical analysis confirmed the production of aldosterone, cortisol, and dehydroepiandrosterone but not dehydroepiandrosterone sulfate in the tree shrew adrenal glands. Furthermore, genes in adrenal cell types in tree shrews were correlated with genetic risk factors for polycystic ovary syndrome, primary aldosteronism, hypertension, and related disorders in humans based on genome-wide association studies. Overall, this study suggests that the adrenal glands of Chinese tree shrews may consist of closely related cell populations with functional similarity to those of the human adrenal gland. Our comprehensive results (publicly available at http://gxmujyzmolab.cn:16245/scAGMap/) should facilitate the advancement of this animal model for the investigation of adrenal gland disorders.
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- 2024
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10. The Parameters Governing the Anti-Myopia Efficacy of Chromatically Simulated Myopic Defocus in Tree Shrews.
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She Z and Gawne TJ
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- Animals, Tupaiidae, Refraction, Ocular, Hyperopia physiopathology, Hyperopia therapy, Photic Stimulation methods, Myopia physiopathology, Myopia therapy, Disease Models, Animal
- Abstract
Purpose: We previously showed that exposing tree shrews (Tupaia belangeri, small diurnal mammals closely related to primates) to chromatically simulated myopic defocus (CSMD) counteracted small-cage myopia and instead induced hyperopia (approximately +4 diopters [D]). Here, we explored the parameters of this effect., Methods: Tree shrews were exposed to the following interventions for 11 days: (1) rearing in closed (n = 7) or open (n = 6) small cages; (2) exposed to a video display of Maltese cross images with CSMD combined with overhead lighting (n = 4); (3) exposed to a video display of Maltese cross images with zero blue contrast ("flat blue," n = 8); and (4) exposed to a video display of black and white grayscale tree images with different spatial filtering (blue pixels lowpass <1 and <2 cycles per degree [CPD]) for the CSMD., Results: (1) Tree shrews kept in closed cages, but not open cages, developed myopia. (2) Overhead illumination reduced the hyperopia induced by CSMD. (3) Zero-blue contrast produced hyperopia but slightly less than the CSMD. (4) Both of the CSMD tree images counteracted small cage myopia, but the one low pass filtering blue <1 CPD was more effective at inducing hyperopia., Conclusions: Any pattern with reduced blue contrast at and below approximately 1 CPD counteracts myopia/promotes hyperopia, but maximal effectiveness may require that the video display be the brightest object in the environment., Translational Relevance: Chromatically simulated myopic blur might be a powerful anti-myopia therapy in children, but the parameter selection could be critical. Issues for translation to humans are discussed.
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- 2024
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11. A bright future for the tree shrew in neuroscience research: Summary from the inaugural Tree Shrew Users Meeting.
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Savier, Elise, Sedigh-Sarvestani, Madineh, Wimmer, Ralf, and Fitzpatrick, David
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TUPAIIDAE ,NEUROSCIENCES ,OPTOGENETICS ,COVID-19 pandemic ,PHYLOGENY - Abstract
Tree shrews (Tupaia spp.) have been used in neuroscience research since the 1960s due to their evolutionary proximity to primates. The use of and interest in this animal model have recently increased, in part due to the adaptation of modern neuroscience tools in this species. These tools include quantitative behavioral assays, calcium imaging, optogenetics and transgenics. To facilitate the exchange and development of these new technologies and associated research findings, we organized the inaugural “Tree Shrew Users Meeting” which was held online due to the COVID-19 pandemic. Here, we review this meeting and discuss the history of tree shrews as an animal model in neuroscience research and summarize the current themes being investigated using this animal, as well as future directions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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12. Comparative In Vivo Imaging of Retinal Structures in Tree Shrews, Humans, and Mice.
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Grannonico M, Miller DA, Liu M, Krause MA, Savier E, Erisir A, Netland PA, Cang J, Zhang HF, and Liu X
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- Humans, Mice, Animals, Rats, Shrews, Retina diagnostic imaging, Retinal Ganglion Cells pathology, Tupaia, Tupaiidae
- Abstract
Rodent models, such as mice and rats, are commonly used to examine retinal ganglion cell damage in eye diseases. However, as nocturnal animals, rodent retinal structures differ from primates, imposing significant limitations in studying retinal pathology. Tree shrews ( Tupaia belangeri ) are small, diurnal paraprimates that exhibit superior visual acuity and color vision compared with mice. Like humans, tree shrews have a dense retinal nerve fiber layer (RNFL) and a thick ganglion cell layer (GCL), making them a valuable model for investigating optic neuropathies. In this study, we applied high-resolution visible-light optical coherence tomography to characterize the tree shrew retinal structure in vivo and compare it with that of humans and mice. We quantitatively characterize the tree shrew's retinal layer structure in vivo, specifically examining the sublayer structures within the inner plexiform layer (IPL) for the first time. Next, we conducted a comparative analysis of retinal layer structures among tree shrews, mice, and humans. We then validated our in vivo findings in the tree shrew inner retina using ex vivo confocal microscopy. The in vivo and ex vivo analyses of the shrew retina build the foundation for future work to accurately track and quantify the retinal structural changes in the IPL, GCL, and RNFL during the development and progression of human optic diseases., (Copyright © 2024 Grannonico et al.)
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- 2024
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13. Identification of novel mammalian viruses in tree shrews ( Tupaia belangeri chinensis ).
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Zhou H, Tian RR, Wang XR, Yang JX, Wang YX, Zhao ML, Zhang XD, Ma YH, Lv LB, Holmes EC, Zheng YT, and Shi WF
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- Animals, Phylogeny, Primates, Shrews, Tupaiidae, Tupaia physiology, Viruses
- Abstract
The Chinese tree shrew ( Tupaia belangeri chinensis ), a member of the mammalian order Scandentia, exhibits considerable similarities with primates, including humans, in aspects of its nervous, immune, and metabolic systems. These similarities have established the tree shrew as a promising experimental model for biomedical research on cancer, infectious diseases, metabolic disorders, and mental health conditions. Herein, we used meta-transcriptomic sequencing to analyze plasma, as well as oral and anal swab samples, from 105 healthy asymptomatic tree shrews to identify the presence of potential zoonotic viruses. In total, eight mammalian viruses with complete genomes were identified, belonging to six viral families, including Flaviviridae , Hepeviridae , Parvovirinae , Picornaviridae , Sedoreoviridae , and Spinareoviridae . Notably, the presence of rotavirus was recorded in tree shrews for the first time. Three viruses - hepacivirus 1, parvovirus, and picornavirus - exhibited low genetic similarity (<70%) with previously reported viruses at the whole-genome scale, indicating novelty. Conversely, three other viruses - hepacivirus 2, hepatovirus A and hepevirus - exhibited high similarity (>94%) to known viral strains. Phylogenetic analyses also revealed that the rotavirus and mammalian orthoreovirus identified in this study may be novel reassortants. These findings provide insights into the diverse viral spectrum present in captive Chinese tree shrews, highlighting the necessity for further research into their potential for cross-species transmission.
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- 2024
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14. Heterogenous thinning of peripapillary tissues occurs early during high myopia development in juvenile tree shrews.
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KhalafAllah MT, Fuchs PA, Nugen F, El Hamdaoui M, Levy AM, Samuels BC, and Grytz R
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- Animals, Humans, Tupaiidae, Tupaia, Shrews, Retina, Tomography, Optical Coherence methods, Myopia etiology, Glaucoma complications
- Abstract
Myopia is an independent risk factor for glaucoma, but the link between both conditions remains unknown. Both conditions induce connective tissue remodeling at the optic nerve head (ONH), including the peripapillary tissues. The purpose of this study was to investigate the thickness changes of the peripapillary tissues during experimental high myopia development in juvenile tree shrews. Six juvenile tree shrews experienced binocular normal vision, while nine received monocular -10D lens treatment starting at 24 days of visual experience (DVE) to induce high myopia in one eye and the other eye served as control. Daily refractive and biometric measurements and weekly optical coherence tomography scans of the ONH were obtained for five weeks. Peripapillary sclera (Scl), choroid-retinal pigment epithelium complex (Ch-RPE), retinal nerve fiber layer (RNFL), and remaining retinal layers (RRL) were auto-segmented using a deep learning algorithm after nonlinear distortion correction. Peripapillary thickness values were quantified from 3D reconstructed segmentations. All lens-treated eyes developed high myopia (-9.8 ± 1.5 D), significantly different (P < 0.001) from normal (0.69 ± 0.45 D) and control eyes (0.76 ± 1.44 D). Myopic eyes showed significant thinning of all peripapillary tissues compared to both, normal and control eyes (P < 0.001). At the experimental end point, the relative thinning from baseline was heterogeneous across tissues and significantly more pronounced in the Scl (-8.95 ± 3.1%) and Ch-RPE (-16.8 ± 5.8%) when compared to the RNFL (-5.5 ± 1.6%) and RRL (-6.7 ± 1.8%). Furthermore, while axial length increased significantly throughout the five weeks of lens wear, significant peripapillary tissue thinning occurred only during the first week of the experiment (until a refraction of -2.5 ± 1.9 D was reached) and ceased thereafter. A sectorial analysis revealed no clear pattern. In conclusion, our data show that in juvenile tree shrews, experimental high myopia induces significant and heterogeneous thinning of the peripapillary tissues, where the retina seems to be protected from profound thickness changes as seen in Ch-RPE and Scl. Peripapillary tissue thinning occurs early during high myopia development despite continued progression of axial elongation. The observed heterogeneous thinning may contribute to the increased risk for pathological optic nerve head remodeling and glaucoma later in life., Competing Interests: Declaration of competing interest Mahmoud T. KhalafAllah, None; Preston A. Fuchs, None; Fred Nugen, None; Mustapha El Hamdaoui, None; Alexander M. Levy, None; Brian C. Samuels, Heidelberg Engineering provided Spectralis OCT2 at no cost (F); Rafael Grytz, Heidelberg Engineering provided Spectralis OCT2 at no cost (F)., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2024
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15. A novel tree shrew model of lipopolysaccharide-induced acute respiratory distress syndrome.
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He J, Zhao Y, Fu Z, Chen L, Hu K, Lin X, Wang N, Huang W, Xu Q, He S, He Y, Song L, Xia Fang M, Zheng J, Chen B, Cai Q, Fu J, and Su J
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- Animals, Humans, Lipopolysaccharides toxicity, Tupaia, Tupaiidae, Positron Emission Tomography Computed Tomography, Shrews, Disease Models, Animal, Primates, Lung Injury, Respiratory Distress Syndrome chemically induced, Respiratory Distress Syndrome diagnostic imaging, Respiratory Distress Syndrome pathology
- Abstract
Introduction: Acute respiratory distress syndrome (ARDS) is a leading cause of respiratory failure, with substantial attributable morbidity and mortality. The small animal models that are currently used for ARDS do not fully manifest all of the pathological hallmarks of human patients, which hampers both the studies of disease mechanism and drug development., Objectives: To examine whether the phenotypic changes of primate-like tree shrews in response to a one-hit lipopolysaccharides (LPS) injury resemble human ARDS features., Methods: LPS was administered to tree shrews through intratracheal instillation; then, the animals underwent CT or PET/CT imaging to examine the changes in the structure and function of the whole lung. The lung histology was analyzed by H&E staining and immunohistochemical staining of inflammatory cells., Results: Results demonstrated that tree shrews exhibited an average survival time of 3-5 days after LPS insult, as well as an obvious symptom of dyspnea before death. The ratios of PaO
2 to FiO2 (P/F ratio) were close to those of moderate ARDS in humans. CT imaging showed that the scope of the lung injury in tree shrews after LPS treatment were extensive. PET/CT imaging with18 F-FDG displayed an obvious inflammatory infiltration. Histological analysis detected the formation of a hyaline membrane, which is usually present in human ARDS., Conclusion: This study established a lung injury model with a primate-like small animal model and confirmed that they have similar features to human ARDS, which might provide a valuable tool for translational research., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)- Published
- 2024
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16. A tree shrew model for steroid-associated osteonecrosis.
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Qi Chen, Zhao-Xia Ma, Li-Bin Xia, Zhen-Ni Ye, BaoLing Liu, Tie-Kun Ma, Peng-Fei Bao, Xing-Fei Wu, Cong-Tao Yu, Dai-Ping Ma, Yuan-Yuan Han, Wen Guang Wang, De-Xuan Kuang, Jie-Jie Dai, Rong Ping Zhang, Min Hu, Hong Shi, Wen-Lin Wang, and Yan-Jiao Li
- Subjects
TUPAIIDAE ,OSTEONECROSIS ,LIPOPOLYSACCHARIDES ,METHYLPREDNISOLONE ,SCANNING electron microscopy - Abstract
The article highlights a study we used a low dose of lipopolysaccharide (LPS) combined with a high dose of methylprednisolone (MPS) to induce a model of femoral head necrosis in tree shrews. It discusses that the model was established in 12 weeks as determined by biochemical analysis, micro-CT examinations, histological analyses, and scanning electron microscopy; and concludes that it replicated a tree shrew model of human hormone-induced osteonecrosis.
- Published
- 2020
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17. Social avoidance behavior in male tree shrews and prosocial behavior in male mice toward unfamiliar conspecifics in the laboratory.
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Rong-Jun Ni, Yang Tian, Xin-Ye Dai, Lian-Sheng Zhao, Jin-Xue Wei, Jiang-Ning Zhou, Xiao-Hong Ma, and Tao Li
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TUPAIIDAE ,PROSOCIAL behavior ,SOCIAL interaction ,MEDICAL research ,SOCIAL phobia - Abstract
Adult male tree shrews vigorously defend against intruding male conspecifics. However, the characteristics of social behavior have not been entirely explored in these males. In this study, male wild-type tree shrews (Tupaia belangeri chinensis) and C57BL/6J mice were first allowed to familiarize themselves with an open-field apparatus. The tree shrews exhibited a short duration of movement (moving) in the novel environment, whereas the mice exhibited a long duration of movement. In the 30 min social preference-avoidance test, target animals significantly decreased the time spent by the experimental tree shrews in the social interaction (SI) zone, whereas experimental male mice exhibited the opposite. In addition, experimental tree shrews displayed a significantly longer latency to enter the SI zone in the second 15 min session (targetpresent) than in the first 15 min session (targetabsent), which was different from that found in mice. Distinct behavioral patterns in response to a conspecific male were also observed in male tree shrews and mice in the first, second, and third 5 min periods. Thus, social behaviors in tree shrews and mice appeared to be time dependent. In summary, our study provides results of a modified social preference-avoidance test designed for the assessment of social behavior in tree shrews. Our findings demonstrate the existence of social avoidance behavior in male tree shrews and prosocial behavior in male mice toward unfamiliar conspecifics. The tree shrew may be a new animal model, which differs from mice, for the study of social avoidance and prosocial behaviors. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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18. The frugivorous insectivores? Functional morphological analysis of molar topography for inferring diet in extant treeshrews (Scandentia).
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Selig, Keegan R, Sargis, Eric J, and Silcox, Mary T
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FUNCTIONAL analysis ,DIET ,TOPOGRAPHY ,TUPAIIDAE - Abstract
The ecology, and particularly the diet, of treeshrews (order Scandentia) is poorly understood compared to that of their close relatives, the primates. This stems partially from treeshrews having fast food transit times through the gut, meaning fecal and stomach samples only represent a small portion of the foodstuffs consumed in a given day. Moreover, treeshrews are difficult to observe in the wild, leading to a lack of observational data in the literature. Although treeshrews are mixed feeders, consuming both insects and fruit, it is currently unknown how the relative importance of these food types varies across Scandentia. Previous study of functional dental morphology has provided an alternative means for understanding the diet of living euarchontans. We used dental topographic metrics to quantify aspects of functional dental morphology in a large sample of treeshrews (n = 58). We measured relief index, Dirichlet normal energy, and three-dimensional orientation patch count rotated, which quantify crown relief, occlusal curvature, and complexity, respectively. Our results suggest that treeshrews exhibit dental morphology consistent with high levels of insectivory relative to other euarchontans. They also suggest that taxa such as Dendrogale melanura and Tupaia belangeri appear to be best suited to insectivory, whereas taxa such as T. palawanensis and T. gracilis appear to be best adapted to frugivory. Our results suggest that Ptilocercus lowii is characterized by a dentition better adapted to insectivory than the early primate Purgatorius. If P. lowii represents a good modern analogue for primitive euarchontans, this contrast would support models of primate origins that include a shift to greater frugivory. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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19. First 3D Dental Topographic Analysis of the Enamel-Dentine Junction in Non-Primate Euarchontans: Contribution of the Enamel-Dentine Junction to Molar Morphology.
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Selig, Keegan R., López-Torres, Sergi, Sargis, Eric J., and Silcox, Mary T.
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PRIMATES ,DENTAL enamel microabrasion ,PTILOCERCUS lowii ,TUPAIIDAE ,THREE-dimensional imaging - Abstract
Molar morphology plays a key role in the systematics and behavioral interpretation of fossil taxa, so understanding the developmental patterns that shape occlusal morphology in modern taxa is of central importance to informing analysis of the fossil record. The shape of the outer enamel surface (OES) of a tooth is largely the result of the forming and folding of the inner enamel epithelium, which is preserved in fully formed teeth as the enamel-dentine junction (EDJ). Previous research on living primates has shown that the degree of correlation between the EDJ and OES can be used to inform our understanding of developmental patterns because lower correlations imply that later developmental events modify the template provided by the EDJ more extensively. Here, we use three topographic metrics to investigate the degree of correlation between the EDJ and OES across living euarchontans by analyzing treeshrews and dermopterans in addition to primates. We found that all living euarchontans show a high degree of topographical correlation, whereas non-primates, especially basally divergent taxa such as Ptilocercus lowii, show the highest degree of correlation between these two surfaces. Our results indicate, that while it is the earlier stages of dental development that have the most influence on overall crown morphology in euarchontans generally, among primates, anthropoids have a lower degree of correlation, implying a greater emphasis on later phases of dental development. This provides insight relevant to interpreting the evolutionary context of the diversity of dental form observed within Euarchonta. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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20. Tree shrews as a new animal model for systemic sclerosis research.
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Zheng L, Chen S, Wu Q, Li X, Zeng W, Dong F, An W, Qin F, Lei L, and Zhao C
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- Humans, Animals, Mice, Tupaiidae, Shrews, Disease Models, Animal, Fibrosis, Inflammation, Bleomycin toxicity, Tupaia, Scleroderma, Systemic chemically induced, Scleroderma, Systemic genetics
- Abstract
Objective: Systemic sclerosis (SSc) is a chronic systemic disease characterized by immune dysregulation and fibrosis for which there is no effective treatment. Animal models are crucial for advancing SSc research. Tree shrews are genetically, anatomically, and immunologically closer to humans than rodents. Thus, the tree shrew model provides a unique opportunity for translational research in SSc., Methods: In this study, a SSc tree shrew model was constructed by subcutaneous injection of different doses of bleomycin (BLM) for 21 days. We assessed the degree of inflammation and fibrosis in the skin and internal organs, and antibodies in serum. Furthermore, RNA sequencing and a series of bioinformatics analyses were performed to analyze the transcriptome changes, hub genes and immune infiltration in the skin tissues of BLM induced SSc tree shrew models. Multiple sequence alignment was utilized to analyze the conservation of selected target genes across multiple species., Results: Subcutaneous injection of BLM successfully induced a SSc model in tree shrew. This model exhibited inflammation and fibrosis in skin and lung, and some developed esophageal fibrosis and secrum autoantibodies including antinuclear antibodies and anti-scleroderma-70 antibody. Using RNA sequencing, we compiled skin transcriptome profiles in SSc tree shrew models. 90 differentially expressed genes (DEGs) were identified, which were mainly enriched in the PPAR signaling pathway, tyrosine metabolic pathway, p53 signaling pathway, ECM receptor interaction and glutathione metabolism, all of which are closely associated with SSc. Immune infiltration analysis identified 20 different types of immune cells infiltrating the skin of the BLM-induced SSc tree shrew models and correlations between those immune cells. By constructing a protein-protein interaction (PPI) network, we identified 10 hub genes that were significantly highly expressed in the skin of the SSc models compared to controls. Furthermore, these genes were confirmed to be highly conserved in tree shrews, humans and mice., Conclusion: This study for the first time comfirmed that tree shrew model of SSc can be used as a novel and promising experimental animal model to study the pathogenesis and translational research in SSc., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zheng, Chen, Wu, Li, Zeng, Dong, An, Qin, Lei and Zhao.)
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- 2024
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21. RNA sequencing and proteomic profiling reveal alterations by MPTP in chronic stomach mucosal injury in tree shrew Chinese (Tupaia belangeri chinensis).
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Wang CY, Ye YS, Long WH, Li ZL, Zheng H, Lin XR, Zhou W, and Tang DH
- Subjects
- Animals, Shrews genetics, Proteomics, Sequence Analysis, RNA, RNA, Messenger, China, Stomach, Tupaia genetics, Tupaiidae
- Abstract
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that can cause gastrointestinal ulcers by affecting dopamine levels. Therefore, MPTP has been considered a toxic substance that causes gastric ulcer disease in experimental animals. In this study, tree shrews were used as the animal model of gastric mucosa injury, and MPTP was intraperitoneally injected at a lower MPTP dosage 2 mg/kg/day for 13 weeks, while tree shrews were not injected as the control group. Under the light microscope, local congestion or diffuse bleeding points of gastric mucosa and multiple redness and swelling bleeding symptoms on the inner wall were observed in the treatment group, as well as immune cell infiltration was found in HE staining, but no such phenomenon was observed in the control group. In order to explore the molecular basis of changes in MPTP induced gastric mucosa injury, the transcriptome and proteome data of gastric mucosa were analyzed. We observed significant differences in mRNA and protein expression levels under the influence of MPTP. The changes in mRNA and proteins are related to increased immune infiltration, cellular processes and angiogenesis. More differentially expressed genes play a role in immune function, especially the candidate genes RPL4 and ANXA1 with significant signal and core role. There are also differentially expressed genes that play a role in mucosal injury and shedding, especially candidate genes GAST and DDC with certain signaling and corresponding functions. Understanding the factors and molecular basis that affect the expression of related genes is crucial for coping with Emotionality gastric mucosa injury disease and developing new treatment methods to establish the ability to resist disease., (© 2024. The Author(s).)
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- 2024
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22. Isolation, identification, and induced differentiation of satellite cells from skeletal muscle of adult tree shrews.
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Ke S, Feng Y, Luo L, Qin W, Liu H, Nie J, Liang B, Ma H, Xie M, Li J, Niu Z, Li G, Tang A, Xia W, and He G
- Subjects
- Animals, Tupaiidae, Cells, Cultured, Cell Differentiation physiology, Muscle, Skeletal, Muscle Fibers, Skeletal metabolism, Tupaia, Satellite Cells, Skeletal Muscle
- Abstract
A method for the in vitro isolation, purification, identification, and induced differentiation of satellite cells from adult tree shrew skeletal muscle was established. The mixed enzyme digestion method and differential adhesion method were used to obtain skeletal muscle satellite cells, which were identified and induced to differentiate to verify their pluripotency. The use of a mixture of collagenase II, hyaluronidase IV, and DNase I is an efficient method for isolating adult tree shrew skeletal muscle satellite cells. The P3 generation of cells had good morphology, rapid proliferation, high viability, and an "S"-shaped growth curve. Reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence staining indicated that marker genes or proteins were expressed in skeletal muscle satellite cells. After myogenic differentiation was induced, multiple-nucleated myotubes were observed, and the MyHC protein was expressed. The expression of myogenic marker genes changed with the differentiation process. After the induction of adipogenic differentiation, orange-red lipid droplets were observed, and the expression of adipogenic marker genes increased gradually with the differentiation process. In summary, satellite cells from adult tree shrew skeletal muscle were successfully isolated using a mixed enzyme digestion method, and their potential for differentiation into myogenic and adipogenic cells was confirmed, laying a foundation for further in vitro study of tree shrew muscle damage., (© 2023. The Society for In Vitro Biology.)
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- 2024
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23. Repeated Low-level Red-light Therapy: The Next Wave in Myopia Management?
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Salzano AD, Khanal S, Cheung NL, Weise KK, Jenewein EC, Horn DM, Mutti DO, and Gawne TJ
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- Animals, Child, Humans, Eye, Refraction, Ocular, Tupaiidae, Phototherapy, Myopia prevention & control, Hyperopia
- Abstract
Significance: Exposure to long-wavelength light has been proposed as a potential intervention to slow myopia progression in children. This article provides an evidence-based review of the safety and myopia control efficacy of red light and discusses the potential mechanisms by which red light may work to slow childhood myopia progression.The spectral composition of the ambient light in the visual environment has powerful effects on eye growth and refractive development. Studies in mammalian and primate animal models (macaque monkeys and tree shrews) have shown that daily exposure to long-wavelength (red or amber) light promotes slower eye growth and hyperopia development and inhibits myopia induced by form deprivation or minus lens wear. Consistent with these results, several recent randomized controlled clinical trials in Chinese children have demonstrated that exposure to red light for 3 minutes twice a day significantly reduces myopia progression and axial elongation. These findings have collectively provided strong evidence for the potential of using red light as a myopia control intervention in clinical practice. However, several questions remain unanswered. In this article, we review the current evidence on the safety and efficacy of red light as a myopia control intervention, describe potential mechanisms, and discuss some key unresolved issues that require consideration before red light can be broadly translated into myopia control in children., Competing Interests: Conflict of Interest Disclosure: None of the authors have reported a financial conflict of interest. There was no sponsorship for the submitted review., (Copyright © 2023 American Academy of Optometry.)
- Published
- 2023
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24. Characterization of long-term ex vivo expansion of tree shrew spermatogonial stem cells.
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Li C, Bi R, Wang L, Ma YH, Yao YG, and Zheng P
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- Male, Animals, Shrews, Animals, Genetically Modified, Primates genetics, Stem Cells, Tupaia genetics, Tupaiidae
- Abstract
Tree shrews ( Tupaia belangeri chinensis ) share a close relationship to primates and have been widely used in biomedical research. We previously established a spermatogonial stem cell (SSC)-based gene editing platform to generate transgenic tree shrews. However, the influences of long-term expansion on tree shrew SSC spermatogenesis potential remain unclear. Here, we examined the in vivo spermatogenesis potential of tree shrew SSCs cultured across different passages. We found that SSCs lost spermatogenesis ability after long-term expansion (>50 passages), as indicated by the failure to colonize the seminiferous epithelium and generate donor spermatogonia (SPG)-derived spermatocytes or spermatids marking spermatogenesis. RNA sequencing (RNA-seq) analysis of undifferentiated SPGs across different passages revealed significant gene expression changes after sub-culturing primary SPG lines for more than 40 passages on feeder layers. Specifically, DNA damage response and repair genes (e.g., MRE11 , SMC3 , BLM , and GEN1 ) were down-regulated, whereas genes associated with mitochondrial function (e.g., NDUFA9 , NDUFA8 , NDUFA13 , and NDUFB8 ) were up-regulated after expansion. The DNA damage accumulation and mitochondrial dysfunction were experimentally validated in high-passage cells. Supplementation with nicotinamide adenine dinucleotide (NAD
+ ) precursor nicotinamide riboside (NR) exhibited beneficial effects by reducing DNA damage accumulation and mitochondrial dysfunction in SPG elicited by long-term culture. Our research presents a comprehensive analysis of the genetic and physiological attributes critical for the sustained expansion of undifferentiated SSCs in tree shrews and proposes an effective strategy for extended in vitro maintenance.- Published
- 2023
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25. Cyclosporine A induces Epstein-Barr virus reactivation in tree shrew (Tupaia belangeri chinensis) model.
- Author
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Shi N, Chen H, Lai Y, Luo Z, Huang Z, He G, Yi X, Xia W, and Tang A
- Subjects
- Animals, Humans, Tupaia, Herpesvirus 4, Human physiology, Tupaiidae, Leukocytes, Mononuclear, Shrews, Cyclosporine pharmacology, Epstein-Barr Virus Infections
- Abstract
Epstein-Barr virus (EBV) usually exists as a latent infection in immunocompetent hosts but immunosuppressed individuals are at risk for developing EBV reactivation that leads to the uncontrolled proliferation of B lymphocytes. In this study, we have mimicked the immunosuppressed microenvironment in the tree shrew model of EBV infection by using cyclosporine A (CsA). The results showed that EBV-cocultured peripheral blood mononuclear cells (PBMCs) proliferated vigorously in response to CsA treatment in vitro. However, EBV susceptibility in vivo depended on the timing of CsA administration. Reactivation of EBV occurred in the latently EBV-infected tree shrews after treatment with 25 mg/kg/day CsA (EBV > CsA group), whereas tree shrews were no longer susceptible to infection if CsA was administered for five weeks before EBV injection (CsA > EBV group). RNA-seq analysis of both groups identified a further link between immunosuppression and EBV infection. KEGG pathway enrichment analysis revealed a significant enrichment of viral infection-related pathways in the EBV > CsA group, whereas tumor-related pathways were significantly enriched in the CsA > EBV group. A protein-protein interaction network was constructed using Cytoscape for the purpose of identifying hub genes that were then verified using qRT-PCR. In conclusion, the tree shrew model of EBV infection exhibits certain features of EBV infection in humans and serves as a valuable platform for exploring the underlying mechanisms of EBV infection., Competing Interests: Declaration of competing interest The authors declare no potential conflicts of interest., (Copyright © 2023 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)
- Published
- 2023
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26. Characteristics of the tree shrew gut virome.
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Chen, Linxia, Gu, Wenpeng, Liu, Chenxiu, Wang, Wenguang, Li, Na, Chen, Yang, Lu, Caixia, Sun, Xiaomei, Han, Yuanyuan, Kuang, Dexuan, Tong, Pinfen, and Dai, Jiejie
- Subjects
TUPAIIDAE ,HERPESVIRUSES ,NUCLEIC acids ,VIRAL proteins ,PICORNAVIRALES - Abstract
The tree shrew (Tupaia belangeri) has been proposed as an alternative laboratory animal to primates in biomedical research in recent years. However, characteristics of the tree shrew gut virome remain unclear. In this study, the metagenomic analysis method was used to identify the features of gut virome from fecal samples of this animal. Results showed that 5.80% of sequence reads in the libraries exhibited significant similarity to sequences deposited in the viral reference database (NCBI non-redundant nucleotide databases, viral protein databases and ACLAME database), and these reads were further classified into three major orders: Caudovirales (58.0%), Picornavirales (16.0%), and Herpesvirales (6.0%). Siphoviridae (46.0%), Myoviridae (45.0%), and Podoviridae (8.0%) comprised most Caudovirales. Picornaviridae (99.9%) and Herpesviridae (99.0%) were the primary families of Picornavirales and Herpesvirales, respectively. According to the host types and nucleic acid classifications, all of the related viruses in this study were divided into bacterial phage (61.83%), animal-specific virus (34.50%), plant-specific virus (0.09%), insect-specific virus (0.08%) and other viruses (3.50%). The dsDNA virus accounted for 51.13% of the total, followed by ssRNA (33.51%) and ssDNA virus (15.36%). This study provides an initial understanding of the community structure of the gut virome of tree shrew and a baseline for future tree shrew virus investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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27. Tupaia glis Common
- Author
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Kazim, Abdul-Rahman, Houssaini, Jamal, Tappe, Dennis, and Heo, Chong-Chin
- Subjects
Tupaia ,Mammalia ,Tupaiidae ,Tupaia glis ,Animalia ,Biodiversity ,Chordata ,Scandentia ,Taxonomy - Abstract
Tupaia glis (Diard & Duvaucel, 1820) Common treeshrew—Kenchong Sathrax durus Johnson, 1964, Published as part of Kazim, Abdul-Rahman, Houssaini, Jamal, Tappe, Dennis & Heo, Chong-Chin, 2022, An annotated checklist of sucking lice (Phthiraptera: Anoplura) from domestic and wild mammals in Malaysia, with lists of hosts and pathogens, pp. 301-336 in Zootaxa 5214 (3) on page 328, DOI: 10.11646/zootaxa.5214.3.1, http://zenodo.org/record/7389119, {"references":["Johnson, P. T. (1964) The hoplopleurid lice of the Indo-Malayan Subregion (Anoplura: Hoplopleuridae). Miscellaneous Publications of the Entomological Society of America, 4 (3), 68 - 102."]}
- Published
- 2022
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28. An annotated checklist of sucking lice (Phthiraptera: Anoplura) from domestic and wild mammals in Malaysia, with lists of hosts and pathogens
- Author
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ABDUL-RAHMAN KAZIM, JAMAL HOUSSAINI, DENNIS TAPPE, and CHONG-CHIN HEO
- Subjects
Felidae ,Cynocephalidae ,Insecta ,Arthropoda ,Carnivora ,Linognathidae ,Rodentia ,Enderleinellidae ,Suidae ,Hoplopleuridae ,Soricomorpha ,Animalia ,Chordata ,Ecology, Evolution, Behavior and Systematics ,Taxonomy ,Artiodactyla ,Tupaiidae ,Sciuridae ,Biodiversity ,Scandentia ,Haematopinidae ,Polyplacidae ,Muridae ,Dermoptera ,Mammalia ,Pedicinidae ,Bovidae ,Animal Science and Zoology ,Soricidae ,Psocodea ,Hamophthiriidae - Abstract
Literature records of sucking lice (Phthiraptera: Anoplura) from Malaysia were checked and reviewed, resulting in a list of 34 established species belonging to 11 genera (Ancistroplax, Atopophthirus, Enderleinellus, Haematopinus, Hamophthirius, Hoplopleura, Linognathus, Neohaematopinus, Pedicinus, Polyplax and Sathrax). Furthermore, three local and six cosmopolitan louse species are regarded as dubious in Malaysia, due to misidentifications or lack of locality records. Also, pathogens known to be associated with the sucking lice are listed. The alarming conservation status of some Malaysian mammalian host species and their sucking lice warrant more research and imminent action to preserve the biodiversity of the country. This paper presents the first complete checklist of anopluran lice from both Peninsular Malaysia and Malaysian Borneo, including localities, literature references and a host-louse list.
- Published
- 2022
29. Sexual dimorphism in the bed nucleus of the stria terminalis, medial preoptic area and suprachiasmatic nucleus in male and female tree shrews
- Author
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Rong-Jun Ni, Peng-Hao Luo, Jiang-Ning Zhou, and Yu-Mian Shu
- Subjects
Male ,Histology ,Vasoactive intestinal peptide ,Biology ,symbols.namesake ,Vasoactive ,medicine ,Animals ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics ,Sex Characteristics ,Suprachiasmatic nucleus ,Tupaiidae ,Cell Biology ,Anatomy ,Immunohistochemistry ,Preoptic Area ,Medial preoptic area ,Sexual dimorphism ,Stria terminalis ,medicine.anatomical_structure ,Nissl body ,symbols ,Female ,Septal Nuclei ,Suprachiasmatic Nucleus ,Nucleus ,hormones, hormone substitutes, and hormone antagonists ,Developmental Biology - Abstract
Sex differences in behaviour partly arise from the sexual dimorphism of brain anatomy between males and females. However, the sexual dimorphism of the tree shrew brain is unclear. In the present study, we examined the detailed distribution of vasoactive intestinal polypeptide-immunoreactive (VIP-ir) neurons and fibres in the suprachiasmatic nucleus (SCN) and VIP-ir fibres in the bed nucleus of the stria terminalis (BST) of male and female tree shrews. The overall volume of the SCN in male tree shrews was comparable with that in females. However, males showed a significantly higher density of VIP-ir cells and fibres in the SCN than females. The shape of the VIP-stained area in coronal sections was arched, elongated or oval in the lateral division (STL) and the anterior part of the medial division (STMA) of the BST and oval or round in the posterior part of the medial division of the BST (STMP). The volume of the VIP-stained BST in male tree shrews was similar to that in females. The overall distribution of VIP-ir fibres was similar between the sexes throughout the BST except within the STMA, where darkly stained fibres were observed in males, whereas lightly stained fibres were observed in females. Furthermore, male tree shrews showed a significantly higher intensity of Nissl staining in the medial preoptic area (MPA) and the ventral part of the medial division of the BST than females. These findings are the first to reveal sexual dimorphism in the SCN, BST and MPA of the tree shrew brain, providing neuroanatomical evidence of sexual dimorphism in these regions related to their roles in sex differences in physiology and behaviour.
- Published
- 2021
30. A comparison of behavioral paradigms assessing spatial memory in tree shrews.
- Author
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Li CJ, Hui YQ, Zhang R, Zhou HY, Cai X, and Lu L
- Subjects
- Humans, Male, Animals, Adult, Aged, Tupaiidae, Spatial Memory, Shrews, Maze Learning, Disease Models, Animal, Tupaia, Alzheimer Disease
- Abstract
Impairments in spatial navigation in humans can be preclinical signs of Alzheimer's disease. Therefore, cognitive tests that monitor deficits in spatial memory play a crucial role in evaluating animal models with early stage Alzheimer's disease. While Chinese tree shrews (Tupaia belangeri) possess many features suitable for Alzheimer's disease modeling, behavioral tests for assessing spatial cognition in this species are lacking. Here, we established reward-based paradigms using the radial-arm maze and cheeseboard maze for tree shrews, and tested spatial memory in a group of 12 adult males in both tasks, along with a control water maze test, before and after bilateral lesions to the hippocampus, the brain region essential for spatial navigation. Tree shrews memorized target positions during training, and task performance improved gradually until reaching a plateau in all 3 mazes. However, spatial learning was compromised post-lesion in the 2 newly developed tasks, whereas memory retrieval was impaired in the water maze task. These results indicate that the cheeseboard task effectively detects impairments in spatial memory and holds potential for monitoring progressive cognitive decline in aged or genetically modified tree shrews that develop Alzheimer's disease-like symptoms. This study may facilitate the utilization of tree shrew models in Alzheimer's disease research., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2023
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31. The effects of ambient narrowband long-wavelength light on lens-induced myopia and form-deprivation myopia in tree shrews.
- Author
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She Z, Ward AH, and Gawne TJ
- Subjects
- Animals, Humans, Tupaiidae, Eye, Refraction, Ocular, Hyperopia etiology, Myopia etiology
- Abstract
Here we examine the effects of ambient red light on lens-induced myopia and diffuser-induced myopia in tree shrews, small diurnal mammals closely related to primates. Starting at 24 days of visual experience (DVE), seventeen tree shrews were reared in red light (624 ± 10 or 634 ± 10 nm, 527-749 human lux) for 12-14 days wearing either a -5D lens (RL-5D, n = 5) or a diffuser (RLFD, n = 5) monocularly, or without visual restriction (RL-Control, n = 7). Refractive errors and ocular dimensions were compared to those obtained from tree shrews raised in broad-spectrum white light (WL-5D, n = 5; WLFD, n = 10; WL Control, n = 7). The RL-5D tree shrews developed less myopia in their lens-treated eyes than WL-5D tree shrews at the end of the experiment (-1.1 ± 0.9D vs. -3.8 ± 0.3D, p = 0.007). The diffuser-treated eyes of the RLFD tree shrews were near-emmetropic (-0.3 ± 0.6D, vs. -5.4 ± 0.7D in the WLFD group). Red light induced hyperopia in control animals (RL-vs. WL-Control, +3.0 ± 0.7 vs. +1.0 ± 0.2D, p = 0.02), the no-lens eyes of the RL-5D animals, and the no-diffuser eyes of the RLFD animals (+2.5 ± 0.5D and +2.3 ± 0.3D, respectively). The refractive alterations were consistent with the alterations in vitreous chamber depth. The lens-induced myopia developed in red light suggests that a non-chromatic cue could signal defocus to a less accurate extent, although it could also be a result of "form-deprivation" caused by defocus blur. As with previous studies in rhesus monkeys, the ability of red light to promote hyperopia appears to correlate with its ability to retard lens-induced myopia and form-deprivation myopia, the latter of which might be related to non-visual ocular mechanisms., (Copyright © 2023. Published by Elsevier Ltd.)
- Published
- 2023
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32. Epstein Barr virus infection in tree shrews alters the composition of gut microbiota and metabolome profile.
- Author
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Xia W, Liu L, Shi N, Zhang C, Tang A, and He G
- Subjects
- Animals, Humans, Herpesvirus 4, Human, Tupaiidae, Metabolome, Tupaia, Biomarkers, Epstein-Barr Virus Infections, Gastrointestinal Microbiome
- Abstract
Background: Epstein-Barr virus (EBV) infection is a major global threat; its manifestations range from the absence of symptoms to multiorgan malignancies and various gastrointestinal diseases. Analyzing the composition and metabolomic profile of gut microbiota during acute EBV infection might be instrumental in understanding and controlling EBV., Methods: Six tree shrews were inoculated with EBV by intravenous injection. Blood was collected at regular intervals thereafter from the femoral vein to detect EBV and inflammatory biomarker. At the same time, tree shrew faeces were collected for 16 S rRNA gene sequencing and Non-targeted metabolomics analysis., Results: 16 S rRNA gene characterization along with β diversity analysis exhibited remarkable alterations in gut microflora structure with a peak at 7 days post-infection(dpi). Some alterations in the relative richness of bacterial taxon were linked to infectious indicators. Of note, Butyricicoccus relative richness was positively linked to EBV presence in the blood and plasma, the opposite correlation was seen with Variovorax and Paramuribaculum. Non-targeted metabolomics indicated the fecal metabolome profile altered during EBV infection, particularly 7 dpi. The relative abundance of geranic acid and undecylenic acid in stool samples was positively linked to systemic inflammatory biomarkers, and an inverse relationship was reported with the estrone glucuronide, linoleic acid, protoporphyrin IX and tyramine., Conclusion: Collectively, EBV infection in this model correlated with changes in the composition and metabolome profile of the gut microbiota., (© 2023. BioMed Central Ltd., part of Springer Nature.)
- Published
- 2023
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33. The tree shrew as a new animal model for the study of periodontitis.
- Author
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Ma L, Chen R, Zhang Y, Dai Z, Huang G, Yang R, and Yang H
- Subjects
- Rats, Humans, Animals, Tupaia, Tupaiidae, Rats, Sprague-Dawley, X-Ray Microtomography, Disease Models, Animal, Inflammation, Alveolar Bone Loss diagnostic imaging, Alveolar Bone Loss pathology, Periodontitis diagnostic imaging, Periodontitis pathology
- Abstract
Aim: Periodontitis is an inflammatory, infectious disease of polymicrobial origin that can damage tooth-supporting bone and tissue. Tree shrews, evolutionarily closer to humans than commonly used rodent models, have been increasingly used as biomedical models. However, a tree shrew periodontitis model has not yet been established., Materials and Methods: Periodontitis was induced in male tree shrews/Sprague-Dawley rats by nylon thread ligature placement around the lower first molars. Thereafter, morphometric and histological analyses were performed. The distance from the cemento-enamel junction to the alveolar bone crest was measured using micro-computed tomography. Periodontal pathological tissue damage, inflammation and osteoclastogenesis were assessed using haematoxylin and eosin staining and quantitative immunohistochemistry, respectively., Results: Post-operatively, gingival swelling, redness and spontaneous bleeding were observed in tree shrews but not in rats. After peaking, bone resorption decreased gradually until plateauing in tree shrews. Contrastingly, rapid and near-complete bone loss was observed in rats. Inflammatory infiltrates were observed 1 week post operation in both models. However, only the tree shrew model transitioned from acute to chronic inflammation., Conclusions: Our study revealed that a ligature-induced tree shrew model of periodontitis partly reproduced the pathological features of human periodontitis and provided theoretical support for using tree shrews as a potential model for human periodontitis., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2023
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34. Differential effects of clomipramine on depression-like behaviors induced by the chronic social defeat paradigm in tree shrews.
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Shen, Fang, Qi, Keke, Duan, Ying, Li, Yonghui, Liang, Jing, Meng, Xiaolu, Li, Ming, and Sui, Nan
- Subjects
CLOMIPRAMINE ,MENTAL depression ,PSYCHOLOGICAL stress ,SOCIAL interaction ,TUPAIIDAE ,ANTIDEPRESSANTS ,ANHEDONIA ,ANIMAL behavior ,ANIMAL experimentation ,BIOLOGICAL models ,COMPARATIVE studies ,INTERPERSONAL relations ,MAMMALS ,RESEARCH methodology ,MEDICAL cooperation ,MOTIVATION (Psychology) ,RESEARCH ,REWARD (Psychology) ,SOCIAL skills ,EVALUATION research ,PHARMACODYNAMICS - Abstract
Background: Anhedonia is a hallmark symptom in major depression that reflects deficits in hedonic capacity and it is also linked to motivation for reward. However, studies of the features of motivation in depressed tree shrews are rather sparse.Aims: The study aimed to investigate the core feature of depression including lack of interest, motivation reduction, and social avoidance in tree shrews. Furthermore, the effects of the treatment using clomipramine on these depression-like behaviors were assessed.Methods: The paradigm of chronic social defeat in tree shrews was used to evaluate the core feature of depression through examining their sucrose preference, break-point for reward, and social interaction.Results: The results showed that social defeat lowered the curves of the sucrose preference and the break-point, as well as decreased social interaction. The results suggested that the subordinate animals exhibited interest loss, motivational reduction, and social avoidance. After oral treatment with clomipramine (50 mg/kg/day) for four weeks, most of the depression-like behaviors were reversed, whereas the motivational reduction was not clearly affected. Notably, the motivational reduction appeared obviously during the first week after the social defeat, and the conventional tricyclic antidepressant clomipramine did not reverse the reduced motivation.Conclusions: These findings imply that motivational variation might be applied as a more sensitive behavioral index in subordinate animals and could furthermore be used to evaluate potential agents as antidepressants. [ABSTRACT FROM AUTHOR]- Published
- 2018
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35. Staying hot to fight the heat-high body temperatures accompany a diurnal endothermic lifestyle in the tropics.
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Levesque, Danielle L., Tuen, Andrew Alek, and Lovegrove, Barry G.
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BODY temperature regulation ,WARM-blooded animals ,TEMPERATE climate ,SCANDENTIA ,TUPAIIDAE - Abstract
Much of our knowledge of the thermoregulation of endotherms has been obtained from species inhabiting cold and temperate climates, our knowledge of the thermoregulatory physiology of tropical endotherms is scarce. We studied the thermoregulatory physiology of a small, tropical mammal, the large treeshrew (Tupaia tana, Order Scandentia) by recording the body temperatures of free-ranging individuals, and by measuring the resting metabolic rates of wild individuals held temporarily in captivity. The amplitude of daily body temperature (~ 4 °C) was higher in treeshrews than in many homeothermic eutherian mammals; a consequence of high active-phase body temperatures (~ 40 °C), and relatively low rest-phase body temperatures (~ 36 °C). We hypothesized that high body temperatures enable T. tana to maintain a suitable gradient between ambient and body temperature to allow for passive heat dissipation, important in high-humidity environments where opportunities for evaporative cooling are rare. Whether this thermoregulatory phenotype is unique to Scandentians, or whether other warm-climate diurnal small mammals share similar thermoregulatory characteristics, is currently unknown. [ABSTRACT FROM AUTHOR]
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- 2018
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36. Comparison of the properties of neural stem cells of the hippocampus in the tree shrew and rat in vitro.
- Author
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Hu, Yuan-Dong, Zhao, Qiong, Zhang, Xue-Rong, Xiong, Liu-Lin, Zhang, Zi-Bin, Zhang, Piao, Zhang, Rong-Ping, and Wang, Ting-Hua
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NEURAL stem cells ,HIPPOCAMPUS (Brain) ,TUPAIIDAE ,LABORATORY rats ,GLIAL fibrillary acidic protein ,NEUROTROPHINS ,TRANSFORMING growth factors - Abstract
Neural stem cells (NSCs) are characterized by the ability of self‑renewal and capacity to proliferate and produce new nervous tissue. NSCs are capable of differentiating to three lineages of neural cells, including neurons, oligodendrocytes and astrocytes. Furthermore, hippocampal NSCs transplantation can improve the neurological deficits associated with expression of cytokines. Therefore, to compare the properties of NSCs of tree shrews and rats in vitro, NSCs from tree shrews (tsNSCs) and rats f(rNSCs) were isolated. Nestin was used as a marker to identify the cultured NSCs. Neuronal nuclei protein and glial fibrillary acidic protein (GFAP) were utilized to demonstrate the differentiation of NSCs towards neurons and astrocytes, respectively, in vitro. Furthermore, the expression of neurotrophin 3 (NT3), brain‑derived neurotrophic factor (BDNF), glial cell‑derived neurotrophic factor (GDNF) and transforming growth factor (TGF)β1 was also investigated in tsNSCs and rNSCs. The expression of all of the aforementioned proteins was detected using immunofluorescence methods. The results demonstrated that, after 5 days of culture, the average number of neurospheres in the cultured tsNSCs was significantly lower compared with rNSCs (P=0.0031). Additionally, compared with the rNSCs, tsNSCs exhibited an enhanced differentiation ability towards neurons. Furthermore, the expression of NT3 in the tsNSCs was higher compared with rNSCs (P<0.01), while the expression of BDNF was lower (P=0.045). However, no significant differences were observed in the expression level of GDNF and TGFβ1 between rNSCs and tsNSCs. Therefore, these results indicate that tsNSCs exhibit specific characteristics that are different from rNSCs, which provides novel information for the understanding of NSCs obtained from tree shrews. Overall, the results of the current study provide evidence to support the increased application of tree shrews as models for diseases of the central nervous system. [ABSTRACT FROM AUTHOR]
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- 2018
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37. Development of a tree shrew-specific interferon-gamma assay.
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Zhang, Xuemei, Xu, Jingwen, Wu, Zhongxiang, Zhu, Wenbing, and Dong, Shaozhong
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TUPAIIDAE ,INTERFERON gamma ,DISEASE susceptibility ,RECOMBINANT proteins ,ENZYME-linked immunosorbent assay ,ANIMAL models in research - Abstract
Tree shrews (Tupaia belangeri) are small squirrel-like mammals closely related to primates. Due to their susceptibility to several human viruses, tree shrews have been proposed as potential animal models for the study of human viral infections. However, there are no standardized assays currently available for the detection of tree shrew-specific interferon (IFN)-γ, a major cytokine secreted during the antiviral immune response. Herein, we developed a novel enzyme-linked immunosorbent assay (ELISA) for the quantification of IFN-γ in tree shrew serum samples. Tree shrew-specific IFN-γ was expressed in Escherichia coli via fusion with glutathione S-transferase (GST-TS-IFN-γ) to obtain recombinant IFN-γ. To generate anti-IFN-γ monoclonal antibodies, mice were immunized with the GST-TS-IFN-γ recombinant fusion protein, and hybridoma cell lines were established. Similarly, anti-IFN-γ polyclonal antibodies were obtained from immunized rabbits, purified, and conjugated to horseradish peroxidase (HRP). Based on the results obtained from the antibody matching test, we optimized the monoclonal antibody (1:2000) and the HRP-conjugated polyclonal antibody (1:8000) as coating and detection antibodies, respectively. Titration curves were generated with recombinant IFN-γ to develop a sensitive sandwich ELISA; the lowest detection limit of the assay was 20 ng/mL. We also tested mitogen-stimulated tree shrew blood samples in this ELISA, and found significantly higher levels of IFN-γ in the stimulated versus the unstimulated samples. Most importantly, our ELISA system detected native IFN-γ in serum samples from 50 healthy tree shrews. We have thus developed a novel ELISA, and have demonstrated the first ELISA-based measurement of IFN-γ in tree shrew serum samples. [ABSTRACT FROM AUTHOR]
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- 2018
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38. Revealing histological and morphological features of female reproductive system in tree shrew (<italic>Tupaia belangeri</italic>).
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Zhong, Shan, Zhang, Shi-yao, Xing, Hui-jie, Zhang, Xiao-tan, Wang, Guang, Bao, Yong-ping, Fu, Jiang-nan, and Yang, Xuesong
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TUPAIIDAE ,GENITALIA ,PLANT morphology ,FALLOPIAN tubes ,FEMALE reproductive organs - Abstract
The tree shrew has been used as a primate animal model in neuroscience studies but it has only rarely been employed in the study of reproductive systems. This is mainly because we know very little about the histological features of reproductive organs of the tree shrew. In this study, we have systematically analyzed the histology of reproductive organs of tree shrew, in comparison with human organs. The uterus of female tree shrew is uterus biomes unicolis, which is connected with an enveloped ovary through a thin fallopian tube. Histologically, the fallopian tube consists of folded mucosa, muscularis and serosa. Like other mammalian animals, the different developmental stages (primordial, primary, secondary and Graafian follicles) of ovarian follicles including inner oocyte and outer granulosa cells are embedded in the cortex. The luminal endometrium, middle muscular myometrium and serosa constitute the wall of uterus of tree shrew. The uterine endometrium contains simple columnar ciliated cells and goblet cells, and there are rich uterine glands in underlying stroma. Furthermore, these glands of tree shrew are round and smaller during anestrus, and become much longer when they are in estrus. The uterine endometrium in younger animals was less developed when compared to a mature tree shrew. Compared to human uterine endometrium, the histological features of tree shrew are very similar, indicating that it could potentially be good primate animal model for studying the diseases in reproductive system. [ABSTRACT FROM AUTHOR]
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- 2018
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39. Ecogeographic variation and taxonomic boundaries in Large Treeshrews (Scandentia, Tupaiidae: Tupaia tana Raffles, 1821) from Southeast Asia
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Neal Woodman, Eric J. Sargis, Maya M. Juman, and Link E. Olson
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0106 biological sciences ,0303 health sciences ,Ecology ,Osteology ,biology ,Manus ,Zoology ,Tupaia tana ,Subspecies ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Intraspecific competition ,Scandentia ,03 medical and health sciences ,Geography ,Treeshrew ,Tupaiidae ,Genetics ,Animal Science and Zoology ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,Nature and Landscape Conservation - Abstract
The Large Treeshrew, Tupaia tana Raffles, 1821, is a small mammal (~205 g) from Southeast Asia with a complicated taxonomic history. Currently, 15 subspecies are recognized from Borneo, Sumatra, and smaller islands, and many were originally differentiated based on minor pelage differences and small sample sizes. We explored intraspecific variation in T. tana using quantitative osteological data obtained from the hands and skulls of museum specimens. Multivariate analyses reveal extensive overlap among T. tana populations in morphospace, indicating that the majority of currently recognized subspecies are not morphometrically distinct. In contrast, the separation between Bornean and Sumatran populations of T. tana is sufficient to recognize them as different subspecies. Comparisons of Bornean specimens to those on small, offshore islands reveal that the latter average smaller body size. This pattern is inconsistent with Foster’s island rule, which predicts that island populations of small mammals (< 5 kg) will average larger body size relative to mainland forms. A similar lack of support for ecogeographic rules has been noted in T. glis (Diard, 1820), suggesting that these “rules” are poor predictors of geographic variation in treeshrews.
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- 2021
40. The limitations of external measurements for aging small mammals: the cautionary example of the Lesser Treeshrew (Scandentia: Tupaiidae: Tupaia minor Günther, 1876)
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Eric J. Sargis, Ananth Miller-Murthy, Link E. Olson, and Neal Woodman
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0106 biological sciences ,education.field_of_study ,Ecology ,biology ,Range (biology) ,05 social sciences ,Population ,Allopatric speciation ,Zoology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Scandentia ,Treeshrew ,Tupaiidae ,Genetics ,Mammalogy ,0501 psychology and cognitive sciences ,Animal Science and Zoology ,050102 behavioral science & comparative psychology ,Tupaia minor ,education ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
Age is a basic demographic characteristic vital to studies of mammalian social organization, population dynamics, and behavior. To eliminate potentially confounding ontogenetic variation, morphological comparisons among populations of mammals typically are limited to mature individuals (i.e., those assumed to have ceased most somatic growth). In our morphometric studies of treeshrews (Scandentia), adult individuals are defined by the presence of fully erupted permanent dentition, a common criterion in specimen-based mammalogy. In a number of cases, however, we have had poorly sampled populations of interest in which there were potentially useful specimens that could not be included in samples because they lacked associated skulls. Such specimens typically are associated with external body and weight measurements recorded by the original collectors, and we sought to determine whether these data could be used successfully as a proxy for age or at least to establish maturity. We analyzed four traditional external dimensions (head-and-body length, tail length, hind foot length, and ear length) and weight associated with 103 specimens from two allopatric populations of the Lesser Treeshrew (Tupaia minor Günther, 1876) from Peninsular Malaysia and from Borneo, which we treated as separate samples (populations). Individuals were assigned to one of eight age categories based on dental eruption stage, and measurements were compared among groups. In general, mean sizes of infants and subadults were smaller than those of adults, but the majority of subadults fell within the range of variation of adults. The large overlap among infants, subadults, and adults in external measurements and weight indicates that such measures are poor proxies for age in this species, probably for treeshrews in general, and possibly for other small mammals. This has significant implications for any investigation wherein relative age of individuals in a given population is an important consideration.
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- 2021
41. A Novel Tree Shrew Model of Chronic Experimental Autoimmune Uveitis and Its Disruptive Application
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Kaijiao, Hu, Longbao, Lv, Hui, Huang, Guangnian, Yin, Jie, Gao, Jianping, Liu, Yaying, Yang, Wenxin, Zeng, Yan, Chen, Ni, Zhang, Feiyan, Zhang, Yuhua, Ma, and Feilan, Chen
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Tupaia ,Uveitis ,Disease Models, Animal ,Amyloid beta-Peptides ,Immunology ,Tupaiidae ,Animals ,Immunology and Allergy ,Cattle ,Iridocyclitis ,Autoimmune Diseases - Abstract
BackgroundPrevious studies have established several animal models for experimental autoimmune uveitis (EAU) in rodents without the fovea centralis in the human retina. This study aimed to develop and explore the application of a novel EAU model in tree shrews with a cone-dominated retina resembling the human fovea.MethodsTree shrews were clinically and pathologically evaluated for the development and characteristics of EAU immunized with six inter-photoreceptor retinoid-binding proteins (IRBPs). IRBP-specific T-cell proliferation and serum cytokine of tree shrews were evaluated to determine the immune responses. Differentially expressed genes (DEGs) were identified in the eyes of tree shrews with EAU by RNA-sequencing. The disruptive effects of the DEG RGS4 inhibitor CCG 203769 and dihydroartemisinin on the EAU were investigated to evaluate the potential application of tree shrew EAU.ResultsIRBP1197–1211and R14 successfully induced chronic EAU with subretinal deposits and retinal damage in the tree shrews. The immunological characteristics presented the predominant infiltration of microglia/macrophages, dendritic cells, and CD4-T-cells into the uvea and retina and pathogenic T helper (Th) 1 and Th17 responses. The subretinal deposits positively expressed amyloid β-protein (Aβ), CD8, and P2Y purinoceptor 12 (P2RY12). The crucial DEGs in R14-induced EAU, such asP2RY2andadenylate cyclase 4 (ADCY4), were enriched for several pathways, including inflammatory mediator regulation of transient receptor potential (TRP) channels. The upregulatedRGS4in IRBP-induced EAU was associated with mitogen-activated protein kinase (MAPK) activity. RGS4 inhibition and dihydroartemisinin could significantly alleviate the retinal pathological injuries of IRBP1197-1211-induced EAU by decreasing the expression of CD4 T-cells.ConclusionOur study provides a novel chronic EAU in tree shrews elicited by bovine R14 and tree shrew IRBP1197-1211characterized by retinal degeneration, retinal damage with subretinal Aβ deposits and microglia/macrophage infiltration, and T-cell response, probably by altering important pathways and genes related to bacterial invasion, inflammatory pain, microglial phagocytosis, and lipid and glucose metabolism. The findings advance the knowledge of the pathogenesis and therapeutics of the fovea-involved visual disturbance in human uveitis.
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- 2022
42. New ribotype Clostridioides difficile from ST11 group revealed higher pathogenic ability than RT078
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Wenpeng Gu, Jiejie Dai, Yuan Wu, Xiaomei Sun, Wen-Zhu Zhang, Jinxing Lu, Pinfen Tong, Caixia Lu, Wang Yuanyuan, Wenge Li, Wenguang Wang, Na Li, and Yuanyuan Han
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0301 basic medicine ,Male ,medicine.medical_specialty ,China ,pathogenic ability ,Epidemiology ,030106 microbiology ,Immunology ,Bacterial Toxins ,Filaggrin Proteins ,Microbiology ,Gastroenterology ,03 medical and health sciences ,new ribotype ,Bacterial Proteins ,Virology ,Internal medicine ,parasitic diseases ,Drug Discovery ,Medicine ,Animals ,Humans ,In patient ,Enterocolitis, Pseudomembranous ,Spores, Bacterial ,Mice, Inbred BALB C ,Virulence ,business.industry ,Clostridioides difficile ,Tupaiidae ,General Medicine ,Pseudomembranous colitis ,animal models ,030104 developmental biology ,Infectious Diseases ,Clostridium Infections ,Parasitology ,Female ,business ,Clostridioides ,RT078 ,Research Article - Abstract
Clostridioides difficile is the predominant antibiotic-associated enteropathogen associated with diarrhoea or pseudomembranous colitis in patients worldwide. Previously, we identified C. difficile RT078 isolates (CD21062) from elderly patients in China, including two new ribotype strains (CD10010 and CD12038) belonging to the ST11 group, and their genomic features were also investigated. This study compared sporulation, spore germination, toxin expression, flagellar characteristics, and adhesion among these strains in vitro and analysed their pathogenic ability in vivo using animal models. The results showed sporulation and spore germination did not significantly differ among the three C. difficile strains. CD10010 and CD12038 showed higher transcriptional levels of toxins until 48 h; thereafter, the transcriptional levels of toxins remained constant among RT078, CD10010, and CD12038. RT078 showed a loss of flagellum and its related genes, whereas CD12038 showed the highest motility in vitro. Both CD10010 and CD12038 initially showed flg phase OFF, and the flagellar switch reversed to phase ON after 48 h in swim agar. Flagellar proteins and toxins were both upregulated when flg phase OFF changed to flg phase ON status, enhancing their pathogenic ability. CD12038 showed the highest adhesion to Hep-2 cells. Histopathology and inflammation scores demonstrated that CD12038 caused the most severe tissue damage and infection in vivo. The new ribotype strains, particularly CD12038, exhibit higher pathogenic ability than the typical RT078 strain, both in vitro and in vivo. Therefore, more attention should be paid to this new C. difficile strain in epidemiological research; further studies are warranted.
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- 2021
43. A novel tree shrew model of pulmonary fibrosis
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Rui-Han Hu, Mustapha El Hamdaoui, Pulin Che, Xueke Zhao, Rafael Grytz, Yiju Cheng, Qiang Ding, Meimei Wang, A. Brent Carter, and Jennifer L. Larson-Casey
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Primary Cell Culture ,Biology ,Bleomycin ,Pathology and Forensic Medicine ,Extracellular matrix ,03 medical and health sciences ,Idiopathic pulmonary fibrosis ,chemistry.chemical_compound ,0302 clinical medicine ,Fibrosis ,Pulmonary fibrosis ,medicine ,Animals ,Humans ,Lung ,Molecular Biology ,Tupaiidae ,Cell Differentiation ,Cell Biology ,Fibroblasts ,respiratory system ,medicine.disease ,Idiopathic Pulmonary Fibrosis ,respiratory tract diseases ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,030220 oncology & carcinogenesis ,Myofibroblast ,Transforming growth factor - Abstract
Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease without effective therapy. Animal models effectively reproducing IPF disease features are needed to study the underlying molecular mechanisms. Tree shrews are genetically, anatomically, and metabolically closer to humans than rodents or dogs; therefore, the tree shrew model presents a unique opportunity for translational research in lung fibrosis. Here we demonstrate that tree shrews have in vivo and in vitro fibrotic responses induced by bleomycin and pro-fibrotic mediators. Bleomycin exposure induced lung fibrosis evidenced by histological and biochemical fibrotic changes. In primary tree shrew lung fibroblasts, transforming growth factor beta-1 (TGF-β1) induced myofibroblast differentiation, increased extracellular matrix (ECM) protein production, and focal adhesion kinase (FAK) activation. Tree shrew lung fibroblasts showed enhanced migration and increased matrix invasion in response to platelet derived growth factor BB (PDGF-BB). Inhibition of FAK significantly attenuated pro-fibrotic responses in lung fibroblasts. The data demonstrate that tree shrews have in vivo and in vitro fibrotic responses similar to that observed in IPF. The data, for the first time, support that the tree shrew model of lung fibrosis is a new and promising experimental animal model for studying the pathophysiology and therapeutics of lung fibrosis.
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- 2021
44. Comprehensive annotation of the Chinese tree shrew genome by large-scale RNA sequencing and long-read isoform sequencing
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Longbao Lv, Qi-Yun Zhu, Min Xu, Jin-Yan Zhang, Ling Xu, Dandan Yu, Mao-Sen Ye, Yong-Gang Yao, and Yu Fan
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Virus infection ,Computational biology ,Biology ,Tree shrew ,Genome ,Article ,Species Specificity ,Animals ,Protein Isoforms ,Gene family ,Gene ,Ecology, Evolution, Behavior and Systematics ,Base Sequence ,Ecology ,Sequence Analysis, RNA ,Alternative splicing ,Tupaiidae ,RNA ,Genome project ,QL1-991 ,Oligosaccharyltransferase complex ,RNA, Long Noncoding ,Animal Science and Zoology ,Transcriptome ,Zoology ,Genome annotation ,Reference genome - Abstract
The Chinese tree shrew (Tupaia belangeri chinensis) is emerging as an important experimental animal in multiple fields of biomedical research. Comprehensive reference genome annotation for both mRNA and long non-coding RNA (lncRNA) is crucial for developing animal models using this species. In the current study, we collected a total of 234 high-quality RNA sequencing (RNA-seq) datasets and two long-read isoform sequencing (ISO-seq) datasets and improved the annotation of our previously assembled high-quality chromosome-level tree shrew genome. We obtained a total of 3 514 newly annotated coding genes and 50 576 lncRNA genes. We also characterized the tissue-specific expression patterns and alternative splicing patterns of mRNAs and lncRNAs and mapped the orthologous relationships among 11 mammalian species using the current annotated genome. We identified 144 tree shrew-specific gene families, including interleukin 6 (IL6) and STT3 oligosaccharyltransferase complex catalytic subunit B (STT3B), which underwent significant changes in size. Comparison of the overall expression patterns in tissues and pathways across four species (human, rhesus monkey, tree shrew, and mouse) indicated that tree shrews are more similar to primates than to mice at the tissue-transcriptome level. Notably, the newly annotated purine rich element binding protein A (PURA) gene and the STT3B gene family showed dysregulation upon viral infection. The updated version of the tree shrew genome annotation (KIZ version 3: TS_3.0) is available at http://www.treeshrewdb.org and provides an essential reference for basic and biomedical studies using tree shrew animal models.
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- 2021
45. Scleral Crosslinking Using Genipin Can Compromise Retinal Structure and Function in Tree Shrews
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Mustapha El Hamdaoui, Alexander M. Levy, Aaron B. Stuber, Christopher A. Girkin, Timothy W. Kraft, Brian C. Samuels, and Rafael Grytz
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Cellular and Molecular Neuroscience ,Ophthalmology ,Myopia ,Tupaiidae ,Animals ,Iridoids ,Sensory Systems ,Article ,Sclera - Abstract
Scleral crosslinking using genipin has been identified as a promising treatment approach for myopia control. The efficacy of genipin to alter biomechanical properties of the sclera has been shown in several animal models of myopia but its safety profile remains unclear. In this safety study, we aim to investigate the effect of scleral crosslinking using retrobulbar injections of genipin on retinal structure and function at genipin doses that were shown to be effective in slowing myopia progression in juvenile tree shrews. To this end, three or five retrobulbar injections of genipin at 0 mM (sham), 10 mM, or 20 mM were performed in one eye every other day. Form deprivation myopia was induced in the injected eye. We evaluated retinal function using full-field electroretinography and retinal structure using in vivo optical coherence tomography imaging and ex vivo histology. The optical coherence tomography results revealed significant thinning of the peripapillary retinal nerve fiber layer in all genipin treated groups including the lowest dose group, which showed no significant treatment effect in slowing myopia progression. In contrast, inducing form deprivation myopia alone and in combination with sham injections caused no obvious thinning of the retinal nerve fiber layer. Electroretinography results showed a significant desensitizing shift of the b-wave semi-saturation constant in the sham group and the second highest genipin dose group, and a significant reduction in b-wave maxima in the two highest genipin dose groups. The ex vivo histology revealed noticeable degeneration of photoreceptors and retinal pigment epithelium in one of two investigated eyes of the highest genipin dose group. While scleral crosslinking using genipin may still be a feasible treatment option for myopia control, our results suggest that repeated retrobulbar injections of genipin at 10 mM or higher are not safe in tree shrews. An adequate and sustained delivery strategy of genipin at lower concentrations will be needed to achieve a safe and effective scleral crosslinking treatment for myopia control in tree shrews. Caution should be taken if the proposed treatment approach is translated to humans.
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- 2022
46. Auditory brainstem responses after electrolytic lesions in bilateral subdivisions of the medial geniculate body of tree shrews.
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Zhu, Meichan, Li, Heng, Gyanwali, Bibek, He, Guangyao, Qi, Chenglin, Yang, Xuemin, Li, Zhenhua, Yao, Zhenxing, Wang, Zhi, and Tang, Anzhou
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AUDITORY brain stem implants ,BRAIN surgery ,LABORATORY animals ,MEDIAL geniculate body ,TUPAIIDAE ,BRAIN stem physiology ,MAMMAL anatomy ,MAMMAL physiology ,MAMMAL metabolism ,ANIMAL experimentation ,ANIMALS ,AUDITORY evoked response ,AUDITORY perception testing ,BIOLOGICAL models ,CONVALESCENCE ,ELECTRIC stimulation ,HEARING disorders ,MAMMALS ,THALAMUS ,TIME ,NEURAL pathways ,WOUNDS & injuries - Abstract
This study aimed to establish a tree shrew model of bilateral electrolytic lesions in the medial geniculate body (MGB) to determine the advantages of using a tree shrew model and to assess the pattern of sound processing in tree shrews after bilateral electrolytic damage in different parts of the MGB. The auditory brainstem responses (ABRs) of a normal control group (n = 30) and an electrical damage group (n = 30) were tested at 0 h, 24 h, 48 h, 72 h, 7 days, 15 days, and 30 days after surgery. (1) The bilateral ablations group exhibited a significant increase in the ABR threshold of the electrolytic damage group between pre- and post-operation. (2) There were significant increases in the I-VI latencies at 0 h after MGBd and MGBm lesions and at 24 h after MGBv lesion. (3) The amplitudes of wave VI were significantly decreased at 24 h and 48 h after MGBd lesion, at 72 h and 7 days after MGBm lesion, and at 24 h, 48 h, 72 h, and 7 days after MGBv lesion. (1) The electrolytic damage group suffered hearing loss that did not recover and appeared to be difficult to fully repair after bilateral ablation. (2) The latencies and amplitudes of responses in the MGB following bilateral electrolytic lesion were restored to pre-operation levels after 15-30 days, suggesting that a portion of the central nuclei lesion was reversible. (3) The tree shrew auditory animal model has many advantages compared to other animal models, such as greater complexity of brain structure and auditory nuclei fiber connections, which make the results of this experiment more useful for clinical diagnoses compared with studies using rats and guinea pigs. [ABSTRACT FROM AUTHOR]
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- 2017
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47. Depletion of endogenous germ cells in tree shrews in preparation for spermatogonial transplantation.
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TINGTING LIU, YING GUO, LANZHEN YAN, BIN SUN, PING ZHENG, and XUDONG ZHAO
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GERM cells ,TUPAIIDAE ,SPERMATOGENESIS ,SEMINIFEROUS tubules ,BUSULFAN ,PLANTS - Abstract
To achieve successful spermatogonial transplantation, endogenous germ cells must be depleted in recipient animals to allow donor germ cells to colonize efficiently. Busulfan is commonly used for the depletion of endogenous germ cells in recipient males. However, the optimal dose of busulfan is species-specific, and the optimal dose in tree shrews is yet to be determined. The current study aimed to determine the optimal dose of busulfan for effective suppression of endogenous spermatogenesis in tree shrews. Different doses (15, 20, 25, 30, 35, 40 and 45 mg/kg) of busulfan were injected into tree shrews intraperitoneally. Survival rates of the different treatment groups were calculated at 2 weeks and body weights were measured at 4, 6, 8, 10 and 28 weeks post-busulfan treatment. The testes were also removed and weighed at 4, 6, 8, 10 and 28 weeks post-treatment, and the cross and longitude diameters of the testes and diameters of the seminiferous tubules were measured and histologically evaluated. It was observed that there were no significant differences in the survival rates between the 15-35 mg/kg treatment groups and the control group (P>0.05), while the survival rate of the 40 mg/kg treatment group significantly decreased relative to the control group (P<0.05) and the survival rate of the 45 mg/kg treatment group was 0% (P<0.05 vs. control). In addition, the weight and diameters of the testes, diameters of the seminiferous tubules and proportion of normal type tubules in the 40 mg/kg group significantly decreased over 4-10 weeks relative to the control group (P<0.05), though gradually recovered with time. At 28 weeks, the recovery was significant relative to 4 weeks (P<0.05). Similarly, histological analysis indicted that recovery of abnormal tubules was delayed in the 40 mg/kg group relative to the lower dose groups as the 40 mg/kg dose tree shrews had more tubules with no spermatogenesis compared with the lower dose group at the same time points. These data indicate that a busulfan dose of 40 mg/kg is optimal for the depletion of endogenous germ cells in tree shrews. This dose led to maximum suppression of endogenous spermatogenesis while maintaining an acceptable survival rate of >50% of the lethal dose of busulfan for tree shrews. [ABSTRACT FROM AUTHOR]
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- 2017
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48. Distribution of Interstitial Telomeric Sequences in Primates and the Pygmy Tree Shrew (Scandentia).
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Mazzoleni, Sofia, Schillaci, Odessa, Sineo, Luca, and Dumas, Francesca
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PRIMATE genetics ,NUCLEOTIDE sequence ,VERTEBRATE genetics ,TUPAIIDAE ,MATERIAL plasticity ,NUCLEIC acid hybridization - Abstract
It has been hypothesized that interstitial telomeric sequences (ITSs), i.e., repeated telomeric DNA sequences found at intrachromosomal sites in many vertebrates, could be correlated to chromosomal rearrangements and plasticity. To test this hypothesis, we hybridized a telomeric PNA probe through FISH on representative species of 2 primate infraorders, Strepsirrhini ( Lemur catta, Otolemur garnettii, Nycticebus coucang ) and Catarrhini ( Erythrocebus patas, Cercopithecus petaurista, Chlorocebus aethiops, Colobus guereza ), as well as on 1 species of the order Scandentia, Tupaia minor , used as an outgroup for primates in phylogenetic reconstructions. In almost all primate species analyzed, we found a telomeric pattern only. In Tupaia , the hybridization revealed many bright ITSs on at least 11 chromosome pairs, both biarmed and acrocentric. These ITS signals in Tupaia correspond to fusion points of ancestral human syntenic associations, but are also present in other chromosomes showing synteny to only a single human chromosome. This distribution pattern was compared to that of the heterochromatin regions detected through sequential C-banding performed after FISH. Our results in the analyzed species, compared with literature data on ITSs in primates, allowed us to discuss different mechanisms responsible for the origin and distribution of ITSs, supporting the correlation between rearrangements and ITSs. [ABSTRACT FROM AUTHOR]
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- 2017
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49. A diffusion tensor imaging atlas of white matter in tree shrew.
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Dai, Jian-kun, Wang, Shu-xia, Shan, Dai, Niu, Hai-chen, and Lei, Hao
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TUPAIIDAE ,WHITE matter (Nerve tissue) ,SCANDENTIA ,NEOCORTEX ,PATHOLOGICAL psychology ,DIFFUSION tensor imaging - Abstract
Tree shrews are small mammals now commonly classified in the order of Scandentia, but have relatively closer affinity to primates than rodents. The species has a high brain-to-body mass ratio and relatively well-differentiated neocortex, and thus has been frequently used in neuroscience research, especially for studies on vision and neurological/psychiatric diseases. The available atlases on tree shrew brain provided only limited information on white matter (WM) anatomy. In this study, diffusion tensor imaging (DTI) was used to study the WM anatomy of tree shrew, with the goal to establish an image-based WM atlas. DTI and T-weighted anatomical images were acquired in vivo and from fixed brain samples. Deterministic tractography was used for three-dimensional reconstruction and rendering of major WM tracts. Myelin and neurofilaments staining were used to study the microstructural properties of certain WM tracts. Taking into account prior knowledge on tree shrew neuroanatomy, tractography results, and comparisons to the homologous structures in rodents and primates, an image-based WM atlas of tree shrew brain was constructed, which is available to research community upon request. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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50. Morphometric variation of tree shrews (Tupaia belangeri) from different regions.
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Wen-Rong Gao, Wan-Long Zhu, Jia-Hao Fu, Tao Yang, and Zheng-Kun Wang
- Subjects
TUPAIIDAE ,MORPHOMETRICS ,NORTHERN tree shrew ,POPULATION biology ,ANIMAL morphology - Abstract
Phenotypic plasticity is the capacity for individuals to modify their phenotype in response to environmental changes. For example, variation in external and cranial characters have been documented in some small mammals and can result in controversy over classification, which has been the case for tree shrews for decades. However, there are few reports about external and cranial character variation in tree shrews (Tupaia belangeri). Here, such character variants of tree shrews were documented for 11 different sampling sites (Hainan, Daxin, Leye, Xingyi, Hekou, Kunming, Xichang, Dali, Pianma, Tengchong, Mengla) and for laboratory samples. The results showed that external and cranial characters of tree shrews significantly differed among regions, Hainan and Daxin populations were significantly larger than those of other populations, and Leye, Xingyi, Kunming and Xichang populations were smaller. The variation may be related to the habitat of tree shrews and our data may initiate new interest in morphological variants in small mammals. The presented detailed examination of the morphometric characters in tree shrews, and the exposed significant morphological differences among tree shrews, are expected to help in confirming their classification status. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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