postnatal development of area 17 callosal connections in tupaia.the goal of the present study was to investigate the pattern of maturation of callosal projecting neurons in a well-studied mammalian visual system with unique structural and functional properties. studies of the distribution pattern of interhemispheric connections in the adult tree shrew primary visual cortex reveal not only a high concentration of labeled neurons along the area 17/18 border, as in standard experimental animals such as the cat and monkey, but also numerous callosal projecting n ...19921282524
rod bipolar cells in the cone-dominated retina of the tree shrew tupaia belangeri.the tree shrew has a cone-dominated retina with a rod proportion of 5%, in contrast to the common mammalian pattern of rod-dominated retinae. as a first step to elucidate the rod pathway in the tree shrew retina, we have demonstrated the presence of rod bipolar cells and studied their morphology and distribution by light and electron microscopy. rod bipolar cells were labeled with an antiserum against the protein kinase c (pkc), a phosphorylating enzyme. intense pkc immunoreactivity was found in ...19911883767
junctions between interstitial cells of the renal medulla: a freeze-fracture study.cell junctions between interstitial cells of the renal medulla were studied in freeze-fracture replicas of kidneys from rat, rabbit, hamster and the tree-shrew tupaia belangeri. in all species studied a composite type of intercellular junction was found comprising elements of tight junctions and irregular gap junctions of highly variable size and shape. the number of these junctions increased towards the tip of the papilla. our findings suggest that the composite junctions observed play a role i ...1979574802
atrial natriuretic peptide detected by immunocytochemistry in peripheral organs of tupaia belangeri.anp (atrial natriuretic peptide), a peptide found in granules of mammalian atrial cardiac myocytes, has been shown to be active in regulation of blood pressure and body water homeostasis. the existence of anp in atrium, pituitary, adrenal gland, and kidney of the rat had been immunocytochemically demonstrated with an antibody against rat anp (102-126). we used the same antibody in immunocytochemical studies for the detection of anp in peripheral organs of the tree shrew (tupaia belangeri). the a ...19872953699
binding sites of atrial natriuretic peptide in tree shrew adrenal gland.adrenal gland binding sites for atrial natriuretic peptide-(99-126) (anp) were quantitated in tree shrew (tupaia belangeri) by incubation of adrenal sections with (3-[125i]-iodotyrosyl28) atrial natriuretic peptide-(99-126), followed by autoradiography with computerized microdensitometry. in the adrenal glands, there are three types of anp binding sites. one is located in the zona glomerulosa (bmax 84 +/- 6 fmol/mg protein; kd 122 +/- 9 pm); the second in the zona fasciculata and reticularis (bm ...19863025827
histaminergic system in the tree shrew brain.this study mapped the histamine-immunoreactive neuronal system in the brain of the tree shrew (tupaia belangeri) and compared its structure with that of the rat and guinea pig. the histamine-containing cell bodies lay in the posterior ventral hypothalamus in the tuberomammillary complex, as in the rodents. the morphology of this complex resembled that of the rat. the histaminergic axons projected to nearly all parts of the brain. the main ascending bundle ran ventromedially: the densest innervat ...19892768560
[quantitative microscopic morphology of the motor brain regions during ontogenesis of tupaia belangeri and spf-cats]. 1977611705
preliminary observations on experimental leprosy in tupaias (tupaia belangeri yunalis).the tupaia belangeri yunalis (tree shrew) is one of the primitive primates. they were inoculated subcutaneously in the footpad or intravenously with mycobacterium leprae from a patient with multibacillary leprosy. as controls, the footpads of cfw mice were inoculated with the same suspension of m. leprae. the results showed growth of acid-fast bacilli (afb) in the footpads of locally inoculated cfw mice and in the footpads of both locally and intravenously inoculated tupaias. whereas the numbers ...19902181220
acute renal failure in tupaia belangeri and rats.acute renal failure in man can best be simulated in model experiments by using either temporary occlusion of the renal artery or perfusions of noradrenaline into the renal artery. the kidney of the tupaia belangeri, a primitive primate, is more resistant to temporary occlusion of the renal artery than of the rat. in tupaia as in rats, anuria developing 48 hours after temporary ischemia is brought about by intratubular proteinaceous casts blocking the flow of urinary filtrate, most likely at henl ...1979497047
further evidence of tubular blockage after acute ischemic renal failure in tupaia belangeri and rats. 1978153643
[growth parameters of brain and its regions in the albino mouse, tupaia belangeri and spf-cat]. 1975132797
experimental infection of tupaia belangeri (tree shrews) with herpes simplex virus types 1 and 2.the susceptibility of tupaia belangeri (tree shrews, which are primitive prosimian primates) to infection with herpes simplex virus (hsv) and the pathogenesis of hsv in these animals were investigated. juvenile (28--45 days old) and adult (150 days old) animals were inoculated intravenously, intraperitoneally, or subcutaneously with hsv type 1 or 2 (25--10(5) plaque-forming units per animal). clinical illness usually appeared in juvenile animals on the second day after inoculation, and the anima ...1978204709
[quantitative demonstration of cytoarchitectural areas in the cortex of tupaia belangeri and spf-cats]. 1978371188
[qualitative and quantitative examinations of the nucleus motorius n. trigemini in ontogenetic series of male spf cats and tupaia belangeri].the nucl. motorius n. trigemini is qualitatively evaluated in tupaia belangeri and spf-cats with cyto-, myelo- and fibrilloarchitectonis methods. the criteria for demarcating the nucl. motorius n. trigemini are also described. the quantitative evaluation was performed on ontogenetic series of 35 male tupaia belangeri and 47 male spf-cats. the growth of the fresh volume is described with the logistic growth function: y = (formula: see text) the nucl. motorius n. trigemini has bilaterally an ideal ...1979546981
[qualitative and quantitative examinations of the corpus mamillare in the ontogenesis of male tupaia belangeri and spf cats].the cyto-, myelo- and fibrilloarchitectonics of the corpus mamillare were described in 33 male tupaia belangeri at an age of 36 to 536 days of ontogenesis and in 37 male spf-cats at an age of 39 to 584 days of ontogenesis. the fresh volumes of the nucl. medialis and the nucl. lateralis corporis mamillaris of tupaia belangeri were determined and the growth of their fresh volumes described with the 6-parametric growth-function likewise, the nuclei of spf-cat were determined and these data were ana ...1978113454
malignant leydig cell tumour in a tupaia belangeri: case report and literature review of male genital tumours in non-human primates.after a short summary of the few reported tumours of the male genital system in non-human primates, a malignant leydig cell tumour is described in an adult male tupaia belangeri. the tumour had metastasized in the omentum probably by haematogenous spread enabled by the peculiar perivascular growth pattern of the tumour cells. its differential diagnosis versus seminomas and sertoli cell tumours is discussed.19883292834
laminar organization and ultrastructure of gaba-immunoreactive neurons and processes in the dorsal lateral geniculate nucleus of the tree shrew (tupaia belangeri).the distribution and ultrastructure of neurons and neuropil labeled by an antiserum to gamma-aminobutyric acid (gaba) were examined in the lateral geniculate nucleus (lgn) of the tree shrew (tupaia belangeri). the lgn of this species segregates center type and cell class into three distinct pairs of laminae: a medial pair (laminae 1 and 2) containing on-center cells, a more lateral pair (4, 5) containing off-center cells, and 2 laminae (3, 6) containing w-like cells. the relationship between thi ...19883154795
co-localization of xenopsin and gastrin immunoreactivity in gastric antral g-cells.studies indicating evidence for the presence of the amphibian octapeptide xenopsin in gastric mucosa of mammals prompted us to investigate the cellular localization of this peptide. using the peroxidase-antiperoxidase method and a specific antiserum to xenopsin (xen-7) on paraffin and adjacent semithin sections of gastric antral mucosa from man, dog, and tupaia belangeri, we found numerous epithelial cells showing a specific positive immunoreaction. these cells were of typical pyramidal shape an ...19863528076
parallel thalamic activation of the first and second somatosensory areas in prosimian primates and tree tupaia belangeri and galago senegalensis, microelectrode recordings immediately after ablation of the representation of the forelimb in the midportion of the first somatosensory area, s-i, revealed that all parts of the second somatosensory area, s-ii, remained highly responsive to cutaneous stimuli. in this way, prosimian primates, close relatives of simian primates, and tree shrews differ markedly from monkeys in which s-ii is deactivated by comparable ablations, and resemble such mammals a ...19911753020
establishment of lung fibroblastic cell lines from a non-human primate tupaia belangeri and their use in a forward gene mutation assay at the hypoxanthine-guanine phosphoribosyl transferase locus.the cells obtained from a lung of a new-born male tupaia belangeri were maintained in mass culture for greater than 400 days. after 55 population doubling levels (100 days in culture), three cell lines were separately established; these lines showed constant growth properties. one line, designated as t-23, was used for a mutation assay. the t-23 cells showed an absolute plating efficiency of 30-50%, and a population doubling time of 18-19 h in dulbecco's modified eagle's medium containing 10% fe ...19863331674
the early development of the heart of tupaia belangeri, with reference to other mammals.the development of the heart of tupaia belangeri from the first endothelial-lined lumina to the cardiac loop is described in 20 embryos with 2 to 14 somites, from ontogenetic days 11 and 12. bilateral endocardial tubes transporting blood are found in the 8-somite embryo; in the middle cardiac plate, angioblasts and angiocysts are located between them. in the 9-somite embryo, formation of the cardiac loop has started, the endocardial tubes approach each other closely, most of the angiocysts have ...19873605650
characterization of prostaglandin e2 binding to uterine membranes from baboon, rabbit and tree shrew (tupaia belangeri).membrane preparations (100,000 g pellet) of rabbit, baboon and tree shrew (tupaia belangeri) uteri were studied for binding of [3h]prostaglandin e2 ([3h]pge2). unbound [3h]pge2 was separated by filtration through whatman gf/f filters. non-specific binding was determined by the amount of radioactivity associated with the filters in the presence of a 100-fold excess of radioinert pge2. pge2 bound to membranes could be displaced by some other prostaglandin (pg) molecules: pge1, 16,16-dimethyl-pge2, ...19892742743
morphological characterization of human juxtaglomerular apparatus.the recent demonstration of the endothelial fenestration at the juxtaglomerular part of the afferent arteriole facing mesangial and granular cells and finger-like protrusions of urinary space into the region of the lacis in experimental animals like the rat, the mouse, and tupaia belangeri led us to propose the hypothesis of a "short loop" feedback mechanism. to establish whether a further species possesses these morphological features, the jga region was examined in the human kidney. tissue was ...19911881061
development of the lateral geniculate nucleus: interactions between retinal afferent, cytoarchitectonic, and glial cell process lamination in ferrets and tree shrews.we have studied the relationship of retinal afferents, glial cell processes, and neuronal cytoarchitectonics in the lateral geniculate nucleus (lgn) of two species: tree shrews (tupaia belangeri) and ferrets (mustela putoris). both species are relatively immature at birth, allowing the development of these features to be studied in the perinatal period. retinal afferents, visualized by intraocular injection of a wheat germ agglutinin/horseradish peroxidase conjugate (wga-hrp), are apparently the ...19901698826
effects of bicuculline on signal detectability in lateral geniculate nucleus relay cells.the lateral geniculate nucleus conveys the center-surround organized retinal receptive fields to the cortex in a way that does not significantly alter their spatial structure. however, non-retinal influences may change the 'strength' (detectability) of the signal under conditions of anesthesia, arousal and attention. a previous analysis of receiver operating characteristic curves in cat suggests that a reduction in signal detectability occurs in lateral geniculate nucleus (lgn) relay cells in an ...19892743129
treatment of rotavirus infection in tree shrews (tupaia belangeri yunalis) with herbal valeriana jatamansi (vj). 19846570506
laminar organization of on and off regions and ocular dominance in the striate cortex of the tree shrew (tupaia belangeri).the organization of on and off responses and ocular dominance in the striate cortex of the tree shrew was electrophysiologically investigated by using flashed, stationary visual stimuli presented monocularly to either the ipsilateral or contralateral eye. we measured cortical multi-unit activity at 25-micron intervals with glass-insulated platinum-plated tungsten microelectrodes. penetrations were made perpendicular to the cortical layers and the responses were quantitatively analyzed in layers ...19863760256
[trbc receptor on t lymphocytes of human and macaque and its ligand are different from e2 molecule and ligands for cd2].cd2 (e receptor, lfa-3 receptor) and e2 molecules (bernard, 1988) on human t lymphocytes, cd58 (lfa-3, lymphocyte function associated antigen 3) on human erythrocytes and s14,s42,s110-220 molecules (bernard, 1987) of sheep erythrocytes are involved in rosette formation of human t lymphocytes with human or sheep erythrocytes. rosette formation of human and macaque pan-t lymphocytes with tree shrew (tupaia belangeri) red blood cells (trbc) (trbc rosette) has shown different physicochemical propert ...19901708938
cardiodilatin-immunoreactive neurons in the hypothalamus of tupaia.using various region specific antibodies raised against partial sequences of synthetic cardiodilatin (cdd) we detected immunoreactive neurons with their perikarya in the nucleus periventricularis of tupaia belangeri. the fibers could be traced laterally directed towards the amygdaloid complex and some varicosities were also observed in the lateral parts of the nucleus periventricularis. it is postulated that brain cdd represents a new neuropeptide and that these cdd-ir neurons are involved in sp ...19853839983
temporal relationship between noradrenaline release in the central amygdala and plasma noradrenaline secretion in rats and tree pentobarbital anesthetized wistar rats and tree shrews (tupaia belangeri) the hypothalamus, the hippocampus and the amygdala were simultaneously superfused through push-pull cannulae with artificial cerebrospinal fluid. blood samples were withdrawn in order to make an attempt to correlate release rates of noradrenaline (na), adrenaline and dopamine in the above-mentioned areas with plasma catecholamine levels. a strong, positive correlation was found between na release in central amygdala and ...19853991076
relationship of glucagon-somatostatin and gastrin-somatostatin cells in the stomach of the monkey.the stomach of the monkey tupaia belangeri was investigated by serial sections utilizing the indirect immunoperoxidase reaction to demonstrate the distribution of glucagon, gastrin and somatostatin immunoreactive cells. a striking topographical distribution was found. glucagon and somatostatin immunoreactive cells were located in the upper parts, whereas gastrin and somatostatin immunoreactive cells were situated in the lower parts of the stomach. the remaining regions of the stomach did not con ...1977319903
tumors of the respiratory tract observed at the german primate center, 1978-1994.eight spontaneous pulmonary tumors (four bronchiolar tubular adenomas, two bronchiolar adenocarcinomas, two squamous-cell carcinomas) occurred in a total of 54 adult tree shrews (tupaia belangeri) of the gpc colonies between 1978 and 1994. the adenomas and adenocarcinomas consisted of tubularly or trabecularly arranged cuboidal to cylindrical cells interspersed with some pas-positive goblet cells, thus resembling the epithelial lining of respiratory bronchioles of tree shrews. the two squamous-c ...19969210028
[experimental studies on the infection of an adult tree shrew (tupaia belangeri yunalis) with human rotavirus]. 19826293669
experimental infection of adult tupaia belangeri yunalis with human rotavirus. 19836303715
distribution of 239pu in the skeleton of the tree shrew (tupaia belangeri) between 15 and 50 months after injection.the macroscopic and microscopic distribution of intramuscularly injected, essentially monomeric, 239pu was studied in the skeleton of the adult tree shrew (tupaia belangeri). data for the period between 15 and 50 months after injection are presented and compared with the data from earlier time points. between 83 and 500 days after injection the nuclide content and the wet weight of the skeleton decreased to a constant level at about 55 per cent of the maximum values. the microscopic distribution ...19873495513
the tight junctions of renal tubules in the cortex and outer medulla. a quantitative study of the kidneys of six species.quantitative aspects of tight junction morphology were systematically studied in the cortical and outer medullary segments of the distal urinary tubules of rat, hamster, rabbit, cat, dog and the primitive primate tupaia belangeri. only minor differences in junctional architecture were found between straight and convoluted portions of the distal tubule. in contrast, the collecting duct in cortex and outer medulla, in all species, exhibits the most elaborate tight junctions observed along the urin ...19807459986
distribution of plutonium-239 in the skeleton of the tree shrew (tupaia belangeri) during the first 15 months after injection.the macroscopic and microscopic distribution of intramuscularly injected, essentially monomeric 239pu, was studied in the tree shrew (tupaia belangeri). data for the first 15 months after injection are presented. about 50 per cent of the absorbed dose is deposited in the skeleton. the microscopic distribution was analysed in femora, humeri, tibiae and lumbar vertebrae. the initial bone surface activity is about 11 bq/cm2 per 37 kbq/kg injected dose (related to a bone uptake of 50 per cent) and i ...19846607232
experimental infection and the state of viral latency of adult tupaia with herpes simplex virus type 1 and 2 and infection of juvenile tupaia with temperature-sensitive mutants of hsv type 2.the susceptibility of adult tupaia belangeri to infection with herpes simplex virus (hvs) was investigated. adult animals were inoculated intraperitoneally with hsv type 1 or 2. with the exception of hsv-2, strain hg-52, 10(5)--10(6) pfu of all hsv strains caused lethal infection irrespective of the age of the animals. infections hsv was recovered from the spinal cord of those animals which had survived infection with a low dose of virus. the dna of the recovered viruses was compared to the dna ...19806251787
detection of glucagon in pancreatic a-cells by monoclonal antibodies.the production of a mouse monoclonal antibody from a hybrid myeloma and its use for the detection of glucagon in tissue sections is reported. the hybrid clone isolated after fusion of mouse myeloma cells with hyperimmune spleen cells from a mouse previously immunized with porcine glucagon allowed us a standardized and permanent source of monoclonal antibodies in a culture cell system. the monoclonal antibody (3 gl 31) specifically reacts with pancreatic a-cells in several species including pig, ...19853891694
cloning of glucocorticoid receptor and mineralocorticoid receptor cdna and gene expression in the central nervous system of the tree shrew (tupaia belangeri).the glucocorticoid (gr) and the mineralocorticoid (mr) receptor mediate corticosteroid actions in the mammalian brain. here, we report the sequence and distribution of both receptor subtype mrnas in the central nervous system of the tree shrew tupaia belangeri, a non-rodent mammal, phylogenetically located between insectivores and primates. the specific glucocorticoid and mineralocorticoid receptor cdnas were cloned, employing polymerase chain reaction (pcr) based methods. the gr cdna and mr cdn ...19989582428
myoendothelial contacts in glomerular arterioles and in renal interlobular arteries of rat, mouse and tupaia belangeri.cell contacts between elements of the tunica media and the intima in the afferent and efferent glomerular arteriole and in the interlobular artery were studied and evaluated semiquantitatively in thin sections of rat and mouse kidney. in the afferent arterioles, including their juxtaglomerular portion, contacts were seen between endothelial and smooth muscle cells, and between endothelial and granulated (renin producing) cells. the form of these musculo-endothelial contacts varied from simple ap ...19846705035
[ontogenesis of facial muscles in primates].1. the development of facial muscles is studied in embryos of tupaia belangeri, tupaia javanica, nycticebus coucang, galago dimidovii, tarsius bancanus, callithrix jacchus, colobus badius, colobus verus, nasalis larvatus, and homo sapiens. 2. the facial muscles derive from a superficial blastema (anlage of platysma myoides) and another blastema laying beneath the first one (anlage of sphincter colli muscle). both blastemas grow out from mesenchymal cells of the head after the anlagen of all othe ...19807215749
hippocampal glucocorticoid receptor expression in the tree shrew: regulation by psychosocial conflict.1. this study was conducted to determine whether chronic psychosocial conflict alters the expression of glucocorticoid receptor (gr) mrna in the hippocampus of male tree shrews (tupaia belangeri). 2. to generate probes for the in situ hybridization, the tree shrew gr gene was partly cloned. there was a 90% homology between the deduced amino acid sequence of the cloned tree shrew gr and that of the corresponding human gr sequence. 35s-labeled riboprobes which had been transcribed from the tree sh ...19947712516
classes of axons and their distribution in the optic nerve of the tree shrew (tupaia belangeri).it has been suggested that retinal ganglion cells (rgcs) of tupaia can be subdivided into three classes that correspond to the x, y, and w classes in the cat. estimates of these classes as determined by electrophysiological experiments and by histological studies of the retina are at variance. because the rgc classes differ in axon diameter, this parameter could serve as a reliable criterion for the evaluation of rgc classes and their proportions.19979294655
studies on the juxtaglomerular apparatus. vi. sympathetic innervation, catecholamines and the renin-angiotensin-system in rats and tree-shrews (tupaia belangeri).it has previously been reported that the primitive primate tupaia belangeri develops a renal failure when exposed to psychosocial stress. in order to learn if this high susceptibility to stress of the tupaia kidney can be correlated with morphological and functional parameters of the juxtaglomerular apparatus (jga) and the renin-angiotension system, comparative experiments were performed on tupaia and rat. our results reveal an outstandingly high potency of the jga and the renin-angiotensin syst ...19807006824
an x-y homologous pairing segment in tree shrews (tupaia).high-resolution early replication banding of tupaia metaphase chromosomes revealed a synchronous early replicating segment in the short-arm telomeric regions of the active and inactive x chromosomes and in the long-arm telomeric region of the y chromosome. hybridization with the human-derived pseudoautosomal probe 113f (stir) showed that this repeat is conserved and specifically localized within these synchronously early replicating segments of the x short arm and the y long arm of all three tup ...19938467714
human hepatitis b virus and hepatocellular carcinoma. i. experimental infection of tree shrews with hepatitis b virus.tree shrews (tupaia belangeri chinenesis) can be experimentally infected with human hepatitis b virus (hbv) by inoculation with human serum positive for hbv, the experimental infection rate being 55.21%. successive infections have been passed through five generations among the tree shrews inoculated with hbv-positive sera from the infected animals, the average infection rate being 94.0%. the experimental infection of tree shrews with hbv may be prevented by immunization with hepatitis b vaccine, ...19968609151
intestinal trichomoniasis due to tritrichomonas mobilensis in tree shrews (tupaia belangeri).intestinal trichomoniasis was observed in 156 of 202 tupaia belangeri (77.2%). the parasites were located principally in the cecum (75%) and were far less common in the proximal portion of the colon (19%) or terminal portion of the ileum (6%). advanced trichomoniasis was associated with liquid cecal contents but not diarrhea. the trichomonads had a tendency to penetrate the mucosal epithelial layer, causing desquamation of entire crypts. they never penetrated the epithelial basement membrane and ...19958569152
hepatitis b virus infection of tupaia hepatocytes in vitro and in vivo.for the systematic analysis of various clinical and molecular aspects of hepatitis b virus (hbv) infection, an experimental small animal system of hbv infection would be a great advance. the susceptibility to hbv infection, therefore, of hepatocytes from the tree shrew species tupaia belangeri was studied in vitro and in vivo. primary hepatocytes isolated from livers of tupaias can be reproducibly infected with hbv. in vitro infection results in viral dna and rna synthesis in hepatocytes and sec ...19968707245
transmission of hepatitis c virus infection to tree shrews.although hepatitis c virus (hcv) infection can be reproduced in chimpanzees, these animals are rare and expensive. tree shrews (tupaias) are small animals, closely related to primates, which adapt easily to a laboratory environment. in this work we have investigated the susceptibility of tupaia belangeri chinensis to hcv infection. tupaias caught in the wild in yunnan (china) were inoculated in china with hcv genotype 1b (study a) and in spain with a mixture of genotypes 1b, 1a, and 3 (study b). ...19989601519
chronic psychosocial stress causes apical dendritic atrophy of hippocampal ca3 pyramidal neurons in subordinate tree shrews.we have shown previously that repeated laboratory restraint stress or daily corticosterone administration affects the structure of ca3 hippocampal neurons in rats. in the present study, we investigated the effect of repeated daily psychosocial stress on the structure of hippocampal ca3 pyramidal neurons in male tree shrews (tupaia belangeri). male tree shrews develop social hierarchies in which subordinates show characteristic changes in physiological and behavioral parameters when confronted wi ...19968627386
[studies on the isolation of endogenous sleep factors from tupaia belangeri chinensis (tbc) after sleep deprivation].the present study was undertaken to explore endogenous sleep factors isolated from 48-72 h sleep deprived (sd) male tupaia belangeri chinensis (tbc). only drink ad libitum (10% glucose) was available within 24 h before collection of urine. controlled "clean" urinary samples were pooled and stored at 20 c. fraction i-v from the urine were determined after ultrafiltration and sephadex-g15. amino-acid analysis of each fraction was automatically done by a 835 amino-acid analyzer, respectively. bioas ...19948085174
monoamine receptors in the amygdaloid complex of the tree shrew (tupaia belangeri).although it is well known that the mammalian amygdala comprises a heterogeneous complex of cytoarchitectonically and histochemically distinct nuclei, the association of these nuclei with different monoamine systems has not been described in detail. we therefore investigated the pattern of receptors for monoamines in the amygdala of the tree shrew (tupaia belangeri). binding sites for the alpha 2-adrenoceptor ligand (3h)rauwolscine, the alpha 1-adrenoceptor ligand (3h)prazosin, the beta-adrenocep ...19948034790
an animal study on transmission of hepatitis b virus through mosquitoes.three gena of mosquitoes were fed with human blood infected with hepatitis b virus (hbv) artificially. when blood in the stomach was completely digested, mosquitoes were used to bite monkeys tupaia belangeri. a month after biting, venous blood samples were taken from the monkeys to detect serum hbsag, hbeag, anti-hbs and anti-hbc. among 29 test monkeys, 9 were hbv infective serum markers positive. in 4 of 16 test monkey liver biopsies, acute inflammatory changes were found with hematoxylin-eosin ...19958728939
age-related levels of urinary free cortisol in the tree shrew.there are still controversies concerning the effect of aging on the basal glucocorticoid concentration in mammals, including humans. some studies reported an elevated glucocorticoid concentration in older subjects, while other reports showed no increases with age. these discrepancies may be caused by different experimental designs, gender differences, or varying sampling time points. the bulk of animal studies reporting increases of glucocorticoids with age were performed in rats. the present st ...19989733169
corticotropin-releasing factor receptor type 1 from tupaia belangeri--cloning, functional expression and tissue distribution.a cdna clone encoding corticotropin-releasing factor (crf) type 1 (crf-r1) has been isolated from the tree shrew tupaia belangeri with a pcr-based approach. the full-length cdna encoded a 415-amino-acid protein with highest sequence identity (approximately 98%) to human crf-r1 and slightly less identity to rat or mouse crf-r1 (approximately 97%). only eight amino acids (residues 3, 4, 6, 35, 36 and 39 in the n-terminus, residue 232 in transmembrane domain 4 and residue 410 in the c-terminus) dif ...19989851694
isolation and pharmacological characterization of two functional splice variants of corticotropin-releasing factor type 2 receptor from tupaia belangeri.from brain, heart and muscle tissue of the tree shrew (tupaia belangeri), a higher order mammal, cdna clones were isolated that encoded two functional splice variants of the corticotropin-releasing factor (crf) type 2 receptor (crf-r2). the first, full-length splice variant, amplified from brain and heart tissue, encoded a crf receptor protein that is 410 amino acids in length and approximately 96% homologous to human crf-r2alpha. the second, full-length splice variant, derived from skeletal mus ...199910336722
primate-like amyloid-beta sequence but no cerebral amyloidosis in aged tree shrews.a central pathological feature of alzheimer's disease is the profuse deposition of amyloid-beta protein (abeta) in the brain parenchyma and vessel walls. abeta also forms deposits in the brains of a variety of mammals, including all aged non-human primates studied to date. the sequence of abeta in these animals is identical to that in humans. no abeta deposits have been found in the brains of wild-type rats and mice, suggesting that the three amino acid differences between their abeta and that o ...199910466892
the patterns of cell death and of macrophages in the developing forebrain of the tree shrew tupaia belangeri.the patterns of cell death and of macrophages were investigated in the forebrain and eyes of the tree shrew tupaia belangeri during five phases of optic cup formation. seventeen embryos were studied. three- dimensional reconstructions were made from one embryo of each phase. in phase 1 (v-shaped optic evagination) a midline band of cell death passes through the closing anterior neuroporus. from phases 2 (optic vesicle) to 5 (far-advanced invagination) the midline band of cell death extends in th ...200010664177
spontaneous tumours in tree shrews (tupaia belangeri): population a necropsy series at the german primate centre, 63 of 1132 tree shrews were found to have tumours. the youngest affected animal was < 6 months old, but the incidence of tumours increased strikingly beyond 2 years of age; of 17 animals aged > 8 years, no less than 14 (82.4%) were affected. the sites of neoplasia were the genital system (22 cases), haematopoietic system (18 cases of malignant lymphoma, many involving the digestive tract), lungs (14 cases), integument (five cases), digestive tra ...19989651807
how tree shrews (tupaia belangeri) perform in a searching task: evidence for strategy use.this study investigated how male tree shrews (tupaia belangen) performed in a searching task while in their home cages and assessed whether different food distributions affected their performance. the animals were faced with a holeboard containing 9 food sources arranged in a 3 x 3 matrix or in 3 clusters, each containing 3 sources. animals tended to start and end the trials from preferred locations, thereafter solving the task by strategically organizing the reward collection according to a min ...200111824897
reduction of aflatoxin b(1) adduct biomarkers by oltipraz in the tree shrew (tupaia belangeri chinensis).the risk of liver cancer is greatest in people both infected with hepatitis b virus (hbv) and highly exposed to aflatoxin b(1) (afb(1)). the tree shrew (tupaia belangeri chinensis) is a unique species that can be infected with human hbv, is susceptible to afb(1)-induced liver cancer, and shows a synergistic interaction between hbv and afb(1) for liver cancer. in this regard, the tree shrew may be useful for evaluating experimental chemoprevention strategies relevant to high-risk human population ...200010799742
defining the ancestral karyotype of all primates by multidirectional chromosome painting between tree shrews, lemurs and humans.we used multidirectional chromosome painting with probes derived by bivariate fluorescence-activated flow sorting of chromosomes from human, black lemur (eulemur macaco macaco) and tree shrew (tupaia belangeri, order scandentia) to better define the karyological relationship of tree shrews and primates. an assumed close relationship between tree shrews and primates also assists in the reconstruction of the ancestral primate karyotype taking the tree shrew as an "outgroup" species. the results in ...199910591999
pulmonary histiocytosis in tree shrews (tupaia belangeri).granulomatous lesions similar to those of pulmonary histiocytosis in rats developed spontaneously in the lungs of captive tree shrews. incidence peaked in 3-year-old tree shrews. sex dependency was not observed, and development of the granulomas was unrelated to experimental procedures because the lesions were observed in animals from the breeding stock as well. the granulomas consisted of amorphous material, foam cells, and a few foreign body-type multinuclear giant cells; they also contained a ...19979241628
mutations in the p53 tumor suppressor gene in tree shrew hepatocellular carcinoma associated with hepatitis b virus infection and intake of aflatoxin b1.infection with hepadnaviruses and exposure to aflatoxin b1 (afb1) are considered to be major risk factors in the development of hepatocellular carcinoma (hcc) in humans. a high rate of p53 mutations at codon 249 has been reported in these tumors. the tree shrew (tupaia belangeri chinensis) is a useful animal model for the development of hcc after human hepatitis b virus (hbv) infection or afb1 treatment. therefore, it was of particular interest to determine whether the p53 gene in tree shrew hcc ...200010863098
tupaia (tree shrew) adenovirus dna: sequence of the left-hand fragment corresponding to the transforming early region of human adenoviruses.the nucleotide sequence of the left-hand region of the adenovirus dna of the phylogenetically interesting tree shrew, (tupaia belangeri) has been determined. transcription signals, initiation codons, splice sites and termination codons were assigned on the basis of its relatedness to the eia region of human adenoviruses 5, 7 and 12. a consensus sequence for encapsidation of adenoviral dna that is based on the established packaging region of adenovirus 16 is proposed. the sequenced region include ...19836321152
primary hepatocytes of tupaia belangeri as a potential model for hepatitis c virus infection.hepatitis c virus (hcv) is a major cause of chronic hepatitis worldwide, but the study of hcv infection has been hampered by the lack of an in vitro or in vivo small animal model. the tree shrew tupaia belangeri is susceptible to infection with a variety of human viruses in vivo, including hepatitis viruses. we show that primary tupaia hepatocytes can be infected with serum- or plasma-derived hcv from infected humans, as measured by de novo synthesis of hcv rna, analysis of viral quasispecies ev ...200211805134
mapping of cytoskeletal components in the hippocampal formation of the tree shrew (tupaia belangeri).the distribution of the major cytoskeletal components in frontal cryosections of the hippocampal formation of adult male tree shrews (tupaia belangeri) was immunohistochemically investigated by using commercially available antibodies. actin-immunolabeling was evident in all layers of the dentate gyrus as well as in the regio superior (ca1) and the regio inferior (ca3). neurofilament 160 was detected only in the molecular layer of the dentate gyrus and in the axons of the granule cells (mossy fib ...199910585159
cold adaptive thermogenesis in small mammals from different geographical zones of china.the mechanisms of thermogenesis and thermoregulation were studied in the tree shrew (tupaia belangeri) and greater vole (eothenomys miletus) of the subtropical region, and brandt's vole (microtus brandti), mongolian gerbil (meriones unguiculatus), daurian ground squirrel (spermophilus dauricus) and plateau pika (ochotona curzoniae) of the northern temperate zone. resting metabolic rate (rmr) and non-shivering thermogenesis (nst) increased significantly in t. belangeri, e. miletus, m. brandti and ...200111440879
immunohistochemical survey of the gut endocrine cells in the common tree shrew (tupaia belangeri).regional distribution and relative frequency of endocrine cells in the gastrointestinal tract of the common tree shrew (tupaia belangeri) were studied immunohistochemically. ten types of immunoreactive endocrine cells were localized in the gastric mucosa, i.e., chromogranin-, serotonin-, gastrin-, somatostatin-, bovine pancreatic polypeptide (bpp)-, enteroglucagon-, pancreatic glucagon-, peptide tyrosine tyrosine (pyy)-, motilin-, and substance p (sp)-immunoreactive (ir) cells. in the intestine, ...199910458098
fmrfamide immunoreactivity and the invasion of adenohypophyseal cells into the neural lobe in the developing pituitary of the tree shrew tupaia belangeri.ontogenetic development of fmrfamide immunoreactivity in the cells and nerve fibers of the pituitary was studied in the tree shrew tupaia belangeri. up to the 26th day of gestation (e26), no fmrfamide immunoreactivity was visible. from e27 onwards it increased continuously until prenatally, on e41, the adult pattern was reached in the adenohypophysis, although at a lower intensity. in the adult tupaia, as in the other mammals studied so far, a finely stained fmrfamide-immunoreactive fiber networ ...199910407096
interlaminar connections of the superior colliculus in the tree shrew. iii: the optic layer.these experiments were designed to test the idea that the optic layer in the tree shrew, tupaia belangeri, is functionally distinct and provides a link between the visuosensory superficial and the premotor intermediate layers of the superior colliculus. first, cells in the optic layer were intracellularly labeled with biocytin in living brain slices. compared to cells in the adjacent lower part of the superficial gray layer, which have apical dendrites that ascend toward the tectal surface, opti ...19979278994
[differentially expressed genes in hepatocellular carcinoma of tree shrew induced by different factors].previous studies on differentially expressed genes in hepatocellular carcinoma (hcc) used to perform with para-cancerous tissues as normal control. however, the para-cancerous tissue of hcc is actually abnormal because they frequently contain hepatitis, cirrhosis, hyperplastic nodules or foci, etc. in order to explore the molecular mechanism and the responsible genes for hepatocarcinogenesis, through applying the hcc model of tree shrew (tupaia belangeri chinensis), this study was designed to co ...200314558942
chronic infection with hepatitis b viruses and antiviral drug evaluation in upa mice after liver repopulation with tupaia hepatocytes.transplantation of primary human hepatocytes and establishment of hepatitis b virus (hbv) infection in immunodeficient urokinase plasminogen activator (upa) transgenic mice was shown. however, the availability of usable primary human hepatocytes is very limited. therefore, alternative and more accessible sources of hepatocytes permissive for hbv infection are highly desirable. here we investigated the potential of primary hepatocytes from the tree shrew tupaia belangeri that were shown to be sus ...200515629507
[studies of hereditary conditionality index on some morphological characters of tupaia belangeri chinensis].tree shrew is a kind of excellent experimental animal resource in medical science and biology. in this paper, 35 tupaia blangeri chinensises (tbcs) captured from kunming,yunnan province were investigated. we analyzed hereditary conditionality index about some morphological characters. according to rife-buranamanas law, we analyzed the appearance characteristics with hereditary conditionality including color of fur, orbit etc. the results showed the following: wild fur with seasonal red spot, whi ...200415640044
hepatitis b virus mutations associated with fulminant hepatitis induce apoptosis in primary tupaia hepatocytes.hepatitis b virus (hbv) core promoter mutations have been implicated in the pathogenesis of fulminant hepatitis b. due to the limited availability of primary human hepatocytes, the functional characterization of hbv mutants has been performed predominantly in transformed cells, which may not represent ideal model systems for studying virus-cell interactions. we and others have shown that primary hepatocytes of the tree shrew tupaia belangeri support hbv infection and replication. in this study, ...200515660384
sympatric distribution of the two morphological types of the common tree shrew in hat-yai districts (south thailand).the two color types (grayish northern and reddish southern types) of the common tree shrew (tupaia glis and tupaia belangeri) were co-distributed in hat-yai region (south thailand). although the isthmus of kra in south thailand has been considered as distribution barrier of the two types, the sympatric distribution of both types was confirmed in southern side of the isthmus. in the principal component analysis, the skull measurement character from hat-yai region could also be separated into the ...200010945296
efficient infection of primary tupaia hepatocytes with purified human and woolly monkey hepatitis b virus.the asian tree shrew, tupaia belangeri, has been proposed as a novel animal model for studying hepatitis b virus (hbv) infection. here, we describe a protocol for efficient and reproducible infection of primary tupaia hepatocytes with hbv. we report that human serum interferes with hbv binding to the hepatocytes, thus limiting the maximum multiplicity of infection. purification of hbv virions by gradient sedimentation greatly enhances virus binding and infectivity. covalently closed circular dna ...200111333889
ovulation in the tree shrew (tupaia belangeri) induced by gonadotrophins.the induction of ovulation by exogenous gonadotrophins is an important approach for recovering oocytes used for studies on the reproductive biology of some mammals. in the present study, pregnant mare serum gonadotrophin (pmsg) and human chorionic gonadotrophin (hcg) were used to induce ovulation in the tree shrew (tupaia belangeri) using the following regimens. groups a1-a3, multiple injections of pmsg (30-60 iu) followed by a single dose of hcg (30-60 iu); b1, combination of a single injection ...200111833933
synergistic effect of hepatitis b virus and aflatoxin b1 in hepatocarcinogenesis in tree animal experiment with tree shrews was performed to detect the synergistic effects of hepatitis b virus (hbv) infection and dietary aflatoxin b1 (afb1) in hepatocarcinogenesis. adult healthy tree shrews (tupaia belangeri chinensis) were divided into four groups: group a (hbv + afb1)--animals were infected with human hbv serum at first, then fed afb1 diluted with milk, 150 ug/, 6 days/week for 105 weeks. group b (hbv)--animals were infected with human hbv as group a, but no afb1 treat ...199910374028
genomic and evolutionary characterization of tt virus (ttv) in tupaias and comparison with species-specific ttvs in humans and non-human virus (ttv) was recovered from the sera of tupaias (tupaia belangeri chinensis) by pcr using primers derived from the noncoding region of the human ttv genome, and its entire genomic sequence was determined. one tupaia ttv isolate (tbc-ttv14) consisted of only 2199 nucleotides (nt) and had three open reading frames (orfs), spanning 1506 nt (orf1), 177 nt (orf2) and 642 nt (orf3), which were in the same orientation as the orfs of the human prototype ttv (ta278). orf3 was presumed to arise from ...200111514713
pre-s1 antigen-dependent infection of tupaia hepatocyte cultures with human hepatitis b virus.the susceptibility of the tree shrew tupaia belangeri to human hepatitis b virus (hbv) has been demonstrated both in vivo and in vitro. in this study, we show that purified hbv infects primary t. belangeri hepatocyte cultures in a very specific manner, as detected by hbv covalently closed circular dna, mrna, hbv e antigen, and hbsag production. a monoclonal antibody (mab), ma18/7, directed against the pre-s1 domain of the large hbs protein, which has been shown to neutralize infectivity of hbv f ...200312915565
the epidemiology of animal trichinellosis in china.the epidemiology of animal trichinellosis in china based mainly upon original chinese literature published between 1937 and 2004 is reviewed. the seroprevalence of trichinella infection in herbivores was 0.7% (2/300) in cattle and 0.8% (4/500) in sheep. the prevalence of trichinellosis in naturally infected cattle was 1.2% (2/163). trichinella larvae were detected in 1.4% (3/215) of sheep and in 2.1% (1/47) of beef cattle sold at markets. canine trichinellosis was recorded in 13 provinces, auton ...200716162414
stress-induced changes in cerebral metabolites, hippocampal volume, and cell proliferation are prevented by antidepressant treatment with tianeptine.stress-induced structural remodeling in the adult hippocampus, involving debranching and shortening of dendrites and suppression of neurogenesis, provides a cellular basis for understanding the impairment of neural plasticity in the human hippocampus in depressive illness. accordingly, reversal of structural remodeling may be a desirable goal for antidepressant therapy. the present study investigated the effect of tianeptine, a modified tricyclic antidepressant, in the chronic psychosocial stres ...200111675510
isolation and molecular characterization of a novel cytopathogenic paramyxovirus from tree shrews.a cytopathic infectious agent was isolated from the kidneys of an apparently healthy tree shrew (tupaia belangeri) that had been captured in the area around bangkok. the infectivity was propagated in tupaia fibroblast and kidney cell cultures. paramyxovirus-like pleomorphic enveloped particles and helical nucleocapsids were observed by electron microscopy and accordingly the infectious agent was termed tupaia paramyxovirus (tpmv). however, no serological cross-reactions were detected between tpm ...199910366580
cytogenetic differentiation of two sympatric tree shrew taxa found in the southern part of the isthmus of kra.sympatric populations of the genus tupaia encompassing two cytotypes (cyt60, 2n = 60 and cyt62, 2n = 62) were found in the southern part of the isthmus of kra (the middle region of the malay peninsula, thailand). c-bands, location of rdna, and location of non-essential telomeric repeats (trs) were investigated in detail for 23 animals captured in the area. such chromosomal traits definitely reveal that two distinct cytotypes exist in the sympatric population, though the external morphological tr ...200212199145
expression and cdna sequence of matrix metalloproteinase-2 (mmp-2) in a mammalian model of human disease processes: tupaia belangeri.matrix metalloproteinase-2 (mmp-2) is one of a family of proteolytic enzymes that are involved in the remodelling of tissue during normal growth processes and is capable of degrading structural components of the extracellular matrix. increases in mmp-2 expression and activity have been reported in diseases that involve degradation of the extracellular matrix. reported here for the first time are the relative levels of expression of mmp-2 in tissues of the tree shrew along with 2587 bases of the ...200415621657
the tree shrews: adjuncts and alternatives to primates as models for biomedical research.the tree shrews are non-rodent, primate-like, small animals. there is increasing interest in using them to establish animal models for medical and biological research. this review focuses on the use of the tree shrews in in vivo studies on viral hepatitis, hepatocellular carcinoma (hcc), myopia, and psychosocial stress. because of the susceptibility of the tree shrews (tupaia belangeri) and their hepatocytes to infection with human hepatitis b virus (hbv) in vivo and in vitro, these animals have ...200312823622
endocrine correlates of reproductive development in the male tree-shrew (tupaia belangeri) and the effects of infantile exposure to exogenous androgens.the developmental life-history of tree-shrews conforms with the general primate pattern. consequently, elucidation of the tree-shrew's neuroendocrine reproductive axis could shed light on the mechanisms that underlie human pubertal development. in the present study, we examined plasma gonadotropin concentrations in male tree-shrews from birth to sexual maturity, and related them to changes in the androgenic and gametogenic status of the testis. a hypogonadotropic infantile phase, during which a ...200717686481
acoustical expression of arousal in conflict situations in tree shrews (tupaia belangeri).empirical research on human and non-human primates suggests that communication sounds express the intensity of an emotional state of a signaller. in the present study, we have examined communication sounds during induced social interactions of a monogamous mammal, the tree shrew. to signal their unwillingness to mate, female tree shrews show defensive threat displays towards unfamiliar males paralleled by acoustically variable squeaks. we assumed that the distance between interacting partners as ...200717520262
the complete mitochondrial genome of tupaia belangeri and the phylogenetic affiliation of scandentia to other eutherian orders.the complete mitochondrial genome of tupaia belangeri, a representative of the eutherian order scandentia, was determined and compared with full-length mitochondrial sequences of other eutherian orders described to date. the complete mitochondrial genome is 16, 754 nt in length, with no obvious deviation from the general organization of the mammalian mitochondrial genome. thus, features such as start codon usage, incomplete stop codons, and overlapping coding regions, as well as the presence of ...200010958850
lipid-mediated introduction of hepatitis b virus capsids into nonsusceptible cells allows highly efficient replication and facilitates the study of early infection events.the hepatitis b virus (hbv) is an enveloped dna virus which is highly infectious in vivo. in vitro, only primary hepatocytes of humans and tupaia belangeri or the novel heparg cell line are susceptible to hbv, but infection is inefficient and study of early infection events in single cells is unsatisfactory. since hepatoma cells replicate the virus efficiently after transfection, this limited infection efficiency must be related to the initial entry phase. here, we describe the lipid-based deliv ...200616699026
full-length genome sequence of mossman virus, a novel paramyxovirus isolated from rodents in australia.mossman virus (mov) was isolated on two occasions from wild rats trapped in queensland, australia, during the early 1970s. together with nariva virus and j-virus mov belongs to a group of novel paramyxoviruses isolated from rodents during the last 40 years, none of which had been characterized at the molecular level until now. cdna subtraction strategies used to isolate virus-specific cdna derived from both mov-infected cells and crude mov pellets were pivotal steps in rapid characterization of ...200314698671
differential expression of genes during aflatoxin b(1)-induced hepatocarcinogenesis in tree shrews.through exploring the regulation of gene expression during hepatocarcinogenesis induced by aflatoxin b(1) (afb(1)), to find out the responsible genes for hepatocellular carcinoma (hcc) and to further understand the underlying molecular mechanism.200414966905
toxic effect of chloromycetin on the ultrastructures of the motor neurons of the chinese tree shrew (tupaia belangeri).this paper describes the toxic effects of chloromycetin on the motor neurons of the chinese tree shrew (tupaia belangeri chinensis) with horse radish peroxidase (hrp) as the labeling enzyme. when chloromycetin was administered orally at 2.5 mg/kg (body weight)/day for 3 days, chinese tree shrews showed evidence of neurotoxicity. this included damage in cortical motor neuron synapses ending on neurons of the red nucleus and the ultrastructural changes in the mitochondria such as swelling of these ...200415181466
proteome analysis of aflatoxin b1-induced hepatocarcinogenesis in tree shrew (tupaia belangeri chinensis) and functional identification of candidate protein peroxiredoxin order to explore the proteins responsible for hepatocellular carcinoma (hcc), aflatoxin b(1)-induced hepatocarcinogenesis in tree shrew (tupaia belangeri chinensis) was analyzed with 2-de and ms. by comparing hcc samples with their own precancerous biopsies and hcc-surrounding tissues, a group of candidate proteins that differentially expressed in hcc were obtained. peroxiredoxin (prx) ii, one of the candidates with distinct alteration, was further investigated and validated. western blot and ...200818318006
postnatal lung and metabolic development in two marsupial and four eutherian species.two marsupial species (monodelphis domestica, macropus eugenii) and four eutherian species (mesocricetus auratus, suncus murinus, tupaia belangeri and cavia aperea) were examined to compare and contrast the timing of lung and metabolic development during the postnatal maturation of the mammalian respiratory apparatus. using light, scanning and transmission electron microscopy, the lung structural changes were correlated with indirect calorimetry to track the metabolic development. marsupial and ...200818179474
protection of tree shrews by pvax-ps dna vaccine against hbv infection.the immunological protection of pvax-ps, a dna vaccine, was assessed in the tree shrews model. pvax-ps was constructed by inserting the gene encoding the middle (pre-s2 plus s) envelope protein of hbv into a plasmid vector pvax1. tree shrews (tupaia belangeri chinenesis) were experimentally infected with human hbv by inoculation with human serum positive for hbv markers. dna vaccination-induced seroconversion and antibody to hbv surface antigen (anti-hbs) were analyzed by elisa, and protective e ...200312932306
relationship of the optical coherence tomography signal to underlying retinal histology in the tree shrew (tupaia belangeri).to interpret the retinal origin of the optical coherence tomography (oct) signal by objectively (i.e., minimal investigator bias) aligning in vivo oct longitudinal reflectivity profiles (lrps) with corresponding vertical histologic sections.200918708623
chronic psychosocial stress alters npy system: different effects in rat and tree shrew.the neuropeptide y (npy) system has been largely studied in relation to affective disorders, in particular for its role in the mechanisms regulating the pathophysiology of anxiety and depression and in the stress-related behaviours. although npy has been previously investigated in a variety of animal models of mood disorders, the receptor subtype mainly involved in the modulation of the stress response has not been identified. in the present study, the chronic psychosocial stress based on the re ...201019846047
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