| [plasmodium falciparum and chondroitin-4-sulfate: the new key couple in sequestration]. | some complications of plasmodium falciparum infection such as cerebral malaria and pregnancy-associated malaria may be partially due to cytoadherence of erythrocytes infected by mature parasites on microvascular endothelial cells or placental syncytiotrophoblasts. recently a new cytoadherence receptor, chondroitin-4-sulphate (csa), was identified first on endothelial cells in primates and then on cho cells and purified receptors. further study has implicated csa in cytoadherence of infected red ... | 1998 | 9791601 |
| presence of anti-ovalbumin ige antibody in the sera of laboratory-reared squirrel monkeys (saimiri sciureus) fed quail eggs. | in this study, we examined serum anti-ovalbumin (ova) ige and igg antibodies in laboratory-reared squirrel monkeys (saimiri sciureus), that were fed a boiled quail egg everyday. we found that 36 of 95 monkeys (38%) possessed specific ige and 44% (42/95) had specific igg against ova. these antibody titers seemed to increase with age. there was, however, no apparent correlation between the anti-ova ige and igg antibody titers. | 1998 | 9816496 |
| novel target antigens of the variant-specific immune response to plasmodium falciparum identified by differential screening of an expression library. | a primary infection by the plasmodium falciparum palo alto o and r antigenic variants induces a variant-specific immunity in the saimiri sciureus monkey. we have shown that these variants express distinct pfemp1 antigens and differ in their levels of expression of additional antigens, including two conserved erythrocyte membrane-associated proteins, hrp1 and pfemp3. to identify the antigens eliciting a variant-specific response, we conducted a differential screening of a lambdagt11 library with ... | 1999 | 9864197 |
| analysis on reactivity of human lymphocyte and monocyte-specific antibodies with peripheral blood mononuclear cells from squirrel monkeys (saimiri sciureus) | | 1998 | 9879863 |
| determination of fetal biparietal diameter without the use of ultrasound in squirrel monkeys. | this study evaluated manual caliper measurement of fetal bpd in saimiri through the abdomen of the dam (tbpd) for correlation with paired ultrasound measurements, prediction of delivery date, subspecies variation, prediction of pregnancy outcome, and correlation between postpartum bpd and tbpd. regression analysis revealed a close relationship between tbpd measurements and those obtained by ultrasound (p < 0.001). tbpd for saimiri boliviensis boliviensis increased from a mean of 14.8 +/- 0.3 mm ... | 1998 | 9926983 |
| annual physiological changes in individually housed squirrel monkeys (saimiri sciureus). | this study investigated whether annual changes in physiology occur in individually housed squirrel monkeys (saimiri sciureus). physiological measures were monitored for 20 months. over the course of the study, all individually housed males and females exhibited clear annual changes in gonadal and adrenal hormone levels, and males exhibited species-typical changes in body weight. females exhibited a typical pattern of hormonal changes, with elevations in gonadal steroids occurring during the same ... | 1999 | 9973264 |
| sigma-optokinetic nystagmus in squirrel monkeys elicited by stationary stripe patterns illuminated by regular and random-interval flash sequences. | eye position and angular velocity were measured in squirrel monkeys (saimiri sciureus) by means of the electromagnetic scleral search-coil technique. horizontal sigma-optokinetic nystagmus (sigma-okn) was elicited by a stationary, stroboscopically illuminated, periodic, vertical-stripe pattern lining a vertical cylinder. the relationship between the mean slow-phase eye angular velocity, ve, of sigma-okn and the product of pattern period, ps, and flash frequency, f(s), was determined. when ve app ... | 1999 | 10090657 |
| haemobartonellosis in squirrel monkeys (saimiri sciureus): antagonism between haemobartonella sp. and experimental plasmodium falciparum malaria. | a hemotropic parasite of the genus haemo bartonella (rickettsial parasite of the family anaplasmataceae) is responsible for latent asymptomatic infection in colony-born saimiri monkeys. indeed, many of these animals develop a patent haemobartonella infection following splenectomy. such patent parasitism is characterized by an intense haemobartonella parasitemia which peaks between days 12 and 14 after removal of the spleen and then decreases to become undetectable between days 25 and 30. during ... | 1999 | 10092473 |
| application of in vitro methods using peripheral whole blood to selecting highly susceptible individuals among common squirrel monkeys (saimiri sciureus) to bacterial lipopolysaccharides. | the present study was designed to elucidate whether the individual susceptibility of common squirrel monkeys (saimiri sciureus) to bacterial lipopolysaccharides (lps) can be predicted by in vitro testing batteries performed in advance. of the in vitro tests, the blastogenic response (n = 11) to lps was determined by a micro-blood culture technique, and the production (n = 6) of cytokines such as tumour necrosis factor (tnf-alpha), interleukin-1 (il-1beta) and interleukin-6 (il-6) released into t ... | 1999 | 10227735 |
| molecular characterization of cdnas encoding squirrel monkey (saïmiri sciureus) cd8 alpha and beta chains. | | 1999 | 10369934 |
| presence of platelet-activating factor in rhesus (macaca mulatta) spermatozoa. | platelet-activating factor [1-o-alkyl-2-acetyl-sn-glycero-phosphocholine; paf] is a unique signaling phospholipid which has been implicated in a number of biological activities (e.g., reproduction). paf has been detected in the spermatozoa from a number of laboratory and domestic species, including, but not limited to, rabbit, bovine, and the mouse. the concentration of paf is inversely related to human (homo sapien) spermatozoal quality. additionally, paf levels are significantly higher in boli ... | 1999 | 10372538 |
| neurochemical organization of inferior pulvinar complex in squirrel monkeys and macaques revealed by acetylcholinesterase histochemistry, calbindin and cat-301 immunostaining, and wisteria floribunda agglutinin binding. | to investigate whether the inferior pulvinar complex has a common organization in different primates, the chemoarchitecture of the visual thalamus was re-examined in squirrel monkeys (saimiri sciureus) and macaques (macaca mulatta). the inferior pulvinar (pi) complex consisted of multiple subdivisions and encompassed the classic pi, and adjacent ventral parts of the lateral and medial pulvinar (pl and pm, respectively). in keeping with nomenclature suggested previously for macaques, the pi subdi ... | 1999 | 10379830 |
| [contribution to knowledge of reservoirs of trypanosoma cruzi (chagas, 1909) in corrientes province, argentina]. | in order to identify trypanosoma cruzi reservoirs in transmission areas, 60 mammals in capital and san luis del palmar departments, corrientes, argentina were studied. primates, rodents, carnivores, marsupials and edentates were investigated, 40 of them living in captivity and 20 caught with traps in a rural area. the mammals were examined by xenodiagnosis and third or fourth instars nymphs of triatoma infestans starved for 2 weeks were used. the feces were microscopically observed (400x) for tr ... | 1999 | 10380566 |
| lack of cortico-striatal projections from the primary auditory cortex in the squirrel monkey. | the projections of the superior temporal gyrus to the caudate nucleus were studied in 10 squirrel monkeys (saimiri sciureus). it was found that the primary auditory cortex lacks direct connections with the caudate nucleus as well as the putamen. areas rl and t1 of burton and jones, bordering the primary auditory cortex laterally, show a moderate projection to the body and tail of the caudate nucleus; area t2, bordering areas rl and t1, shows an extensive projection into the head, body and tail. ... | 1999 | 10415425 |
| a cerebral primitive neuroectodermal tumor in a squirrel monkey (saimiri sciureus). | an adult squirrel monkey with a history of long-term exposure to microwave radiation was found at necropsy to have a malignant tumor of the right cerebral cortex. gross examination revealed a mass with expanding borders in the right frontoparietal cortex with compression of the adjacent lateral ventricle. microscopy revealed a tumor composed of sheets of moderate-sized cells, resembling an oligodendroglioma, with clear cytoplasm and central nuclei interrupted by delicate vasculature. malignant f ... | 1999 | 10431699 |
| food avoidance learning in squirrel monkeys and common marmosets. | using a conditioned food avoidance learning paradigm, six squirrel monkeys (saimiri sciureus) and six common marmosets (callithrix jacchus) were tested for their ability to (1) reliably form associations between visual or olfactory cues of a potential food and its palatability and (2) remember such associations over prolonged periods of time. we found (1) that at the group level both species showed one-trial learning with the visual cues color and shape, whereas only the marmosets were able to d ... | 1998 | 10454364 |
| polymorphism in trypomastigotes of trypanosoma (megatrypanum) minasense in the blood of experimentally infected squirrel monkey and marmosets. | experimental infections by trypanosoma (megatrypanum) minasense were performed in primates - saimiri sciureus and callithrix penicillata - with the objective of searching for morphological variations of the blood trypomastigotes with respect to hosts and time of infection. we carried out morphological and morphometric analysis of blood trypomastigotes. illustrations are given. both the squirrel monkey and marmoset became infected after the injection of blood trypomastigotes of t. minasense, alth ... | 1999 | 10464410 |
| behavioral effects of cocaine: interactions with d1 dopaminergic antagonists and agonists in mice and squirrel monkeys. | the present study compared interactions among dopamine d1-like agonists and partial agonists with cocaine on the locomotor stimulant effects of cocaine, as well as the discriminative-stimulus effects of cocaine, and effects of cocaine on rates of responding. cocaine alone produced a dose-related stimulation of locomotor activity in swiss-webster mice and a dose-related increase in the proportion of responses on the cocaine-appropriate response key in squirrel monkeys (saimiri sciureus) trained t ... | 1999 | 10490913 |
| discriminative stimulus effects of zolpidem in squirrel monkeys: comparison with conventional benzodiazepines and sedative-hypnotics. | the present study examined whether zolpidem, an imidazopyridine with selectivity for benzodiazepine (bz)/gamma-aminobutyric acid(a) receptors containing the alpha1-subunit, had discriminative stimulus effects similar to typical bzs and other sedative/hypnotic drugs in primates. squirrel monkeys (saimiri sciureus) were trained to discriminate zolpidem (1.0 mg/kg i.v.) from vehicle under a 10-response fixed-ratio schedule of food delivery. under test conditions, zolpidem (0.1-3.0 mg/kg) increased ... | 1999 | 10565847 |
| two distinct gamma-2 herpesviruses in african green monkeys: a second gamma-2 herpesvirus lineage among old world primates? | primate gamma-2 herpesviruses (rhadinoviruses) have so far been found in humans (kaposi's sarcoma-associated herpesvirus [kshv], also called human herpesvirus 8), macaques (macaca spp.) (rhesus rhadinovirus [rrv] and retroperitoneal fibromatosis herpesvirus [rfhv]), squirrel monkeys (saimiri sciureus) (herpesvirus saimiri), and spider monkeys (ateles spp.) (herpesvirus ateles). using serological screening and degenerate consensus primer pcr for the viral dna polymerase gene, we have detected seq ... | 2000 | 10627572 |
| can squirrel monkeys (saimiri sciureus) learn self-control? a study using food array selection tests and reverse-reward contingency. | eight squirrel monkeys (saimiri sciureus) were presented with 2 stimulus arrays, namely 1 and 4 pieces of food, but they received only the array other than the one they reached for. in this reverse-reward condition, all monkeys initially showed a strong preference for the larger array. one monkey learned to reach toward the smaller array when a large-or-none reward contingency was applied (i.e., no reward followed a reach toward the larger array, but this array was given for a reach toward the s ... | 2000 | 10650546 |
| fluorescence in situ hybridization (fish) maps chromosomal homologies between the dusky titi and squirrel monkey. | the platyrrhini are one of the most karyologically derived groups of primates and the evolution of their karyotypes is far from understood. the identification of the origin and direction of chromosome rearrangements will contribute to a better understanding of new world monkey phylogeny, taxonomy, and evolution. we mapped homology and identified translocations in the chromosomes of the dusky titi monkey (callicebus moloch, 2n = 50) and the squirrel monkey (saimiri sciureus, 2n = 44) by fluoresce ... | 2000 | 10676707 |
| reconciliation in captive guyanese squirrel monkeys (saimiri sciureus). | the tendency for agonistic interaction to increase the probability of friendly interaction between social partners has been demonstrated across a range of old world primates. while research on such post-conflict behavior proceeds into an hypothesis-testing phase, new comparative information must accumulate to provide full phylogenetic perspective on primate social behavior. data from new world and prosimian primates are yet extremely limited. we studied captive squirrel monkeys (saimiri sciureus ... | 2000 | 10676712 |
| effect of infantile strabismus on visuomotor development in the squirrel monkey (saimiri sciureus): optokinetic nystagmus, motion vep and spatial sweep vep. | to determine whether squirrel monkeys made artificially strabismic in infancy had ocular fixation abnormalities, directional asymmetries of horizontal optokinetic nystagmus (okn) and asymmetries of motion visually evoked potentials (mveps) similar to those of humans with infantile strabismus. | 1999 | 10694912 |
| spatial order in short-wavelength-sensitive cone photoreceptors: a comparative study of the primate retina. | we compared the spatial distribution of short-wavelength-sensitive (sws or blue) cone photoreceptors in the retinas of eight primate species. the regularity of the sws cone array was quantified with a statistic (packing factor) that varies between a random distribution (0) and a triangular array (1). we find wide variability among species, with packing factors varying between 0.06 and 0.3. the sws cone array in at least two new world monkey species is indistinguishable from a random array. the s ... | 2000 | 10708037 |
| visual physiology of the lateral geniculate nucleus in two species of new world monkey: saimiri sciureus and aotus trivirgatis. | 1. visual responses were recorded from neurones in the magnocellular and parvocellular layers of the lateral geniculate nucleus (lgn) of the thalamus in two species of new world monkeys - the diurnal squirrel monkey (saimiri sciureus) and the nocturnal owl monkey (aotus trivirgatis). recording sites were reconstructed in postmortem tissue and comparisons were made between the response properties of magnocellular and parvocellular neurones. 2. receptive fields were characterized with both white n ... | 2000 | 10718753 |
| delivering drugs, via microdialysis, into the environment of extracellularly recorded hippocampal neurons in behaving primates. | hippocampal neurons in primates have been extensively studied with electrophysiological and neuroanatomical methods. much less effort has been devoted to examining these cells with contemporary pharmacological techniques. therefore, we modified a recently developed integrative technique (n. ludvig, p.e. potter, s.e. fox, simultaneous single-cell recording and microdialysis within the same brain site in freely behaving rats: a novel neurobiological method, j. neurosci. methods 55 (1994) 31-40 [9] ... | 2000 | 10719268 |
| individual hemispheric asymmetry in vocal fold control of the squirrel monkey. | in ten squirrel monkeys (saimiri sciureus), electrodes were implanted into the left and right facial motor cortex at sites producing bilateral vocal fold adduction when electrically stimulated. all animals, in addition, had electrodes in the periaqueductal grey of the midbrain (pag) at sites producing vocalization when electrically stimulated. in eight out of ten animals, motorcortical stimulation during periaqueductally elicited vocalization caused a change in vocal output. this change, in four ... | 2000 | 10762691 |
| growth of skeletal components in the young squirrel monkey (saimiri sciureus boliviensis): a longitudinal experiment. | a functional skeletal criterion, as an extension of the van der klaauw's cranial theory, was adopted in the present study. the null hypothesis tested was: "the major skeletal components of the platyrrhine body grow linearly, regardless of their functional dependence to different demands." the acceptance of the hypothesis will imply that all saimiri skeletal growth may be satisfactorily explained by independent variables in a single equation. the rejection will suggest that such skeletal growth p ... | 2000 | 10766944 |
| lymphoid organs as a major reservoir for human t-cell leukemia virus type 1 in experimentally infected squirrel monkeys (saimiri sciureus): provirus expression, persistence, and humoral and cellular immune responses. | the aim of this study was to investigate the distribution of human t-cell leukemia virus type 1 (htlv-1) in various organs of serially sacrificed squirrel monkeys (saimiri sciureus) in order to localize the reservoir of the virus and to evaluate the relationship between viral expression and the humoral or cellular immune response during infection. six squirrel monkeys infected with htlv-1 were sacrificed 6, 12, and 35 days and 3, 6, and 26 months after inoculation, and 20 organs and tissues were ... | 2000 | 10775625 |
| new world monkey pepsinogens a and c, and prochymosins. purification, characterization of enzymatic properties, cdna cloning, and molecular evolution. | pepsinogens a and c, and prochymosin were purified from four species of adult new world monkeys, namely, common marmoset (callithrix jacchus), cotton-top tamarin (saguinus oedipus), squirrel monkey (saimiri sciureus), and capuchin monkey (cebus apella). the occurrence of prochymosin was quite unique since this zymogen is known to be neonate-specific and, in primates, it has been thought that the prochymosin gene is not functional. no multiple form has been detected for any type of pepsinogen exc ... | 2000 | 10788784 |
| characterisation of the chondroitin sulphate of saimiri brain microvascular endothelial cells involved in plasmodium falciparum cytoadhesion. | cytoadhesion of plasmodium falciparum-infected erythrocytes (irbc) to chondroitin-4-sulphate (csa) is inhibited by soluble csa in vitro on saimiri brain microvascular endothelial cells (sbec) and in vivo in p. falciparum-infected saimiri monkeys. we tested whether the sbec model was appropriate for studying csa-binding irbc using four cell lines. all sbec expressed a chondroitin sulphate (cs), with a composition of csa. the mean sizes of these csa were 20.5, 22, 23, 32.5 and 36 kda for sbec 3a a ... | 2000 | 10802316 |
| head-related transfer functions of the rhesus monkey. | head-related transfer functions (hrtfs) are direction-specific acoustic filters formed by the head, the pinnae and the ear canals. they can be used to assess acoustical cues available for sound localization and to construct virtual auditory environments. we measured the hrtfs of three anesthetized rhesus monkeys (macaca mulatta) from 591 locations in the frontal hemisphere ranging from -90 degrees (left) to 90 degrees (right) in azimuth and -60 degrees (down) to 90 degrees (up) in elevation for ... | 2000 | 10831867 |
| dilative cardiomyopathy leading to congestive heart failure in a male squirrel monkey (saimiri sciureus). | a 17-year-old, 1-kg, colony-housed, male squirrel monkey (samiri sciureus) developed clinical signs of congestive heart failure. the monkey presented with lethargy, increased heart and respiratory rates, and mild abdominal distention. the clinical history, laboratory analysis, and radiographic findings were consistent with heart failure due to dilative cardiomyopathy. gross and microscopic examination of the heart confirmed a dilative cardiomyopathy. this is the first report describing congestiv ... | 2000 | 10870674 |
| on the search for the vocal pattern generator. a single-unit recording study. | in the squirrel monkey (saimiri sciureus), single-unit activity was compared between the midbrain periaqueductal grey and the parvocellular and central nuclei of the medullary reticular formation during the production of species-specific vocalization. it was found that all three areas contain neurones with vocalization-related activity. the relative number of specific reactions types differed between areas, however. while the majority of periaqueductal cells fired just before, but not during voc ... | 2000 | 10884066 |
| evaluation of immunogenicity and protective efficacy of carrier-free plasmodium falciparum r23 antigen in pre-exposed saimiri sciureus monkeys. | we have reported previously that the recombinant glutathione s-transferase gtr23, induced protection after immunisation of naive or previously exposed saimiri monkeys. we investigated the immunogenicity of carrier-free r23 repeats in pre-exposed animals in two adjuvant formulations. three of five monkeys immunised with alum-formulated repeats and one of two animals immunised with the polyalphaolefine formulation produced high titres of cytophilic antibodies with a primary type kinetics, indicati ... | 2000 | 10924787 |
| in vivo spectrometric calcium flux recordings of intrinsic caudate-putamen cells and transplanted imr-32 neuroblastoma cells using miniature fiber optrodes in anesthetized and awake rats and monkeys. | a method is described to enable the recording of transient intracellular calcium changes in deep brain structures in anesthetized and awake animals using a fluorescent indicator combined with in vivo optical detection methods. optrodes were fabricated using a bifurcated fiber-optic cable with an attached infusion guide cannula. after intracranial implantation of an optrode, animals were prepared in the following manner, (1) rats (intra-striatal) and monkeys (intra-putamen) were infused with the ... | 2000 | 10936638 |
| striking differences in transmission of corticospinal excitation to upper limb motoneurons in two primate species. | there is considerable debate as to the relative importance, for cortical control of upper limb movements, of direct cortico-motoneuronal (cm) versus indirect, propriospinal transmission of corticospinal excitation to cervical motoneurons. in the cat, which has no cm connections, a significant proportion of corticospinal excitation reaches forelimb motoneurons via a system of c(3)-c(4) propriospinal neurons (pn). in contrast, in the macaque monkey most motoneurons receive direct cm connections, a ... | 2000 | 10938297 |
| chemotherapy of haemobartonellosis in squirrel monkeys (saimiri sciureus). | splenectomised saimiri sciureus squirrel monkeys are being used increasingly as an experimental host for human malarial studies, notably for the assessment of candidate vaccines against plasmodium falciparum blood-stage infection. recently, we have reported that colony-reared s. sciureus monkeys are asymptomatic carriers of haemobartonella sp. and that patent haemobartonella infection, activated following splenectomy, may interfere with the course of p. falciparum parasitaemia in these animals. ... | 2000 | 10950456 |
| plasmodium falciparumin the squirrel monkey (saimiri sciureus): infection of non-splenectomised animals as a model for exploring clinical manifestations of malaria. | plasmodium falciparum infection in humans leads to a variety of symptoms ranging from an influenza-like syndrome to life-threatening complications. animal models are useful tools for the detailed analysis of the interaction between both parasite and host factors leading to these various clinical manifestations. in this review, examining the different clinical, parasitological and haematological parameters associated with p. falciparum infection in spleen-intact monkeys, we propose this model as ... | 2000 | 10962278 |
| differential alterations in nicotinic receptor alpha6 and beta3 subunit messenger rnas in monkey substantia nigra after nigrostriatal degeneration. | our previous studies showed that alpha4, alpha6, alpha7, beta2, beta3 and beta4 nicotinic acetylcholine receptor messenger rnas are present in monkey substantia nigra, with a particularly intense and localized labelling of the alpha6 and beta3 subunit messenger rnas to this brain region. because loss of nigrostriatal neurons is a central feature of parkinson's disease and evidence suggests that nicotinic agonists potentiate antiparkinsonian effects of l-dopa, experiments were done to determine w ... | 2000 | 10996459 |
| antioxidant status in a squirrel monkey (saimiri sciureus) with chronic pancreatitis and degenerative myopathy. | a squirrel monkey (saimiri sciureus) presented with wasting, vomiting and diarrhoea. haematology revealed elevation of creatinine phosphokinase, lactic dehydrogenase, alanine aminotransferase, amylase and lipase, together with azotaemia and hypoalbuminaemia. prominent findings were chronic pancreatitis with acinar and ductal plugs, granulomatous and necrotizing peripancreatic steatitis, degenerative myopathy, testicular atrophy, candidiasis and bacterial necrotizing glossitis. antioxidant analys ... | 2000 | 11032677 |
| mammary adenocarcinoma in a male squirrel monkey (saimiri sciureus). | a nodule was identified within the right mammary gland of a 16-year-old male squirrel monkey (saimiri sciureus). the mass was excised and diagnosed as a mammary adenocarcinoma. the monkey developed congestive heart failure 1.5 years later and was euthanatized. at necropsy, a subcutaneous mass was found in the right axillary region. histologically, the mass was identified as a lymph node whose architecture was effaced by neoplastic cells resembling those of the mammary tumor. metastasis to intern ... | 2000 | 11055884 |
| neuronal activity in the medulla oblongata during vocalization. a single-unit recording study in the squirrel monkey. | in six squirrel monkeys (saimiri sciureus), the medulla oblongata was explored with microelectrodes, looking for vocalization-correlated activity. the vocalizations were elicited by microinjections of glutamate agonists into the periaqueductal grey of the midbrain. vocalization-related cells were found in greater numbers in the nucl. ambiguus (ab) and retroambiguus (rab), in the parvocellular, magnocellular and central reticular formation as well as in the solitary tract nucleus and spinal trige ... | 2000 | 11080551 |
| htlv type 1 infection in squirrel monkeys (saimiri sciureus): a promising animal model for htlv type 1 human infection. | we show that the squirrel monkey saimiri sciureus is susceptible to experimental infection with either syngeneic or allogeneic htlv-1-immortalized cells. as in humans, such experimental inoculation leads to chronic infection, and htlv-1 provirus was detected in pbmcs by pcr. chronically infected monkeys developed high titers of antibodies against the structural proteins of the virus, as do htlv-1-infected humans. furthermore, in serially sacrificed squirrel monkeys infected with htlv-1, proviral ... | 2000 | 11080820 |
| two-step nature of human t-cell leukemia virus type 1 replication in experimentally infected squirrel monkeys (saimiri sciureus). | after experimental infection of squirrel monkeys (saimiri sciureus) with human t-cell leukemia virus type 1 (htlv-1)-infected cells, the virus is transcribed only transiently in circulating blood, spleen, and lymph nodes. stable disappearance of viral expression occurs at 2 to 3 weeks after inoculation. this coincides with the development of the anti-htlv-1 immune response and persistent detection of the provirus in peripheral blood mononuclear cells (pbmcs). in this study, the htlv-1 replicatio ... | 2001 | 11134325 |
| morphometric and ultrastructural analysis of different pituitary cell populations in undernourished monkeys. | undernutrition elicited by a low-protein diet determines a marked reduction of hypophyseal activity and affects the function of the respective target organs. the objective of the present investigation was to study the ultrastructural and quantitative immunohistochemical changes of the different pituitary cell populations in undernourished monkeys that had been previously shown to have significant changes in craniofacial growth. twenty saimiri sciureus boliviensis monkeys of both sexes were used. ... | 2001 | 11151030 |
| age differences and developmental trends in alarm peep responses by squirrel monkeys (saimiri sciureus). | alarm calls can code for different classes of predators or different types of predatory threat. acoustic information can also encode the urgency of threat through variations in acoustic features within specific alarm call types. squirrel monkeys (saimiri sciureus) produce an alarm call, known as the alarm peep, in highly threatening situations. infant squirrel monkeys appear to have an innate predisposition to respond to alarm peeps but require experience to associate alarm peeps with the approp ... | 2001 | 11195202 |
| development of a saliva sampling method and a rocket immunoelectrophoretic assay for quantification of salivary iga in the squirrel monkey (saimiri sciureus). | there has long been the requirement for a marker of well being and chronic stress that is, itself, unaffected by the transient stressors associated with sampling. work done in the human, the rat and the dog suggests that salivary iga may fulfil these criteria. this is the first report on the establishment of a saliva sampling technique and immunoelectrophoretic assay for quantification of secretory immunoglobulin a (s-iga) in the squirrel monkey (saimiri sciureus). a safe and effective sampling ... | 2000 | 11204490 |
| cloning of dopamine, norepinephrine and serotonin transporters from monkey brain: relevance to cocaine sensitivity. | we used rt-pcr to clone monoamine transporters from macaca mulatta, macaca fasicularis and saimiri sciureus (dopamine transporter; dat) and macaca mulatta (norepinephrine transporter; net and serotonin transporter; sert). monkey dat, net and sert proteins were >98% homologous to human and, when expressed in hek-293 cells, displayed drug affinities and uptake kinetics that were highly correlated with monkey brain or human monoamine transporters. in contrast to reports of other species, we discove ... | 2001 | 11223167 |
| effect of undernutrition on cranial components and somatotroph-lactotroph pituitary populations in the squirrel monkey (saimiri sciureus boliviensis). | the aim of the present study was to investigate in monkeys the effects of undernutrition on neurocranial and facial components, correlated with a histometric and ultrastructural analysis of somatotroph (growth hormone, gh) and lactotroph (prolactin, prl) pituitary populations. twenty saimiri sciureus boliviensis (cebidae) of both sexes were employed. the monkeys were born in captivity and when they reached 1 year of age, they were separated into two groups: control and undernourished animals. th ... | 2001 | 11275694 |
| seasonal fluctuation of antibody levels to plasmodium falciparum parasitized red blood cell-associated antigens in two senegalese villages with different transmission conditions. | the recombinant r23, pfeb200, and gst-5 antigens derive from conserved antigens associated with the plasmodium falciparum-infected erythrocyte membrane. they were identified as targets of protective antibodies in the saimiri sciureus model. we have assessed here the humoral response to these antigens in humans. cross-sectional surveys were conducted in two senegalese villages with different levels of endemicity. the prevalence of specific igg and igm was similar and influenced by age in both loc ... | 2000 | 11304067 |
| use of the squirrel monkey saimiri sciureus to optimize serological tests for diagnosis of bunyavirus infection in humans. | several arthropod-borne viruses of the large bunyaviridae virus family have been isolated in south america. there are few data about the incidence of these viruses in man, except for the oropuche virus. since haemagglutination inhibition tests are difficult to perform, only enzyme-linked immunosorbent assays (elisas) are used. nevertheless, positive controls are necessary for elisa, and infected humans are rare. squirrel monkeys (saimiri sciureus) were therefore infected experimentally to assess ... | 2001 | 11311344 |
| herpesvirus saimiri. | herpesvirus saimiri (saimiriine herpesvirus 2) is the classical prototype of the gamma(2)-herpesviruses or rhadinoviruses, which also contains a human member, the kaposi's sarcoma-associated herpesvirus. the t-lymphotropic herpesvirus saimiri establishes specific replicative and persistent conditions in different primate host species. virtually all squirrel monkeys (saimiri sciureus) are persistently infected with this virus. in its natural host, the virus does not cause disease, whereas it indu ... | 2001 | 11313011 |
| single-cell recording from the brain of freely moving monkeys. | single-cell recording from the brain of non-human primates has traditionally been performed in monkeys seated in a primate chair. however, this arrangement makes long-term recordings difficult, causes stress that may confound the data, and prevents the manifestation of natural behaviors. extending our previous neurophysiological studies in non-human primates (ludvig et al. brain res. protocols 2000;5:75-85), we have developed a method for recording the electrical activity of single hippocampal n ... | 2001 | 11325438 |
| haptic discrimination of size and texture in squirrel monkeys (saimiri sciureus). | the present study analyzed haptic abilities of four squirrel monkeys. using a two-alternative forced-choice procedure, stimuli were presented in a visually opaque box, allowing unrestrained test subjects to grab through a small opening and touch the discriminanda. difference thresholds were determined by a modified method of limits. in the first experiment we determined size difference thresholds for the discrimination of circular cylinders using standard stimuli differing in diameter from 10 mm ... | 2001 | 11327571 |
| specific gravity of whole blood in cynomolgus monkeys (macaca fascicularis), squirrel monkeys (saimiri sciureus), and tamarins (saguinus labiatus) and total blood volume in cynomolgus monkeys. | blood collection is a common laboratory procedure in animal experiments. the purpose of this study is to establish baseline data for two essential hematologic parameters, total blood volume (tbv) and specific gravity of blood (sgb), of nonhuman primates. the sgb was determined by dropping samples of whole blood into cupric sulfate solution. the values for the mean sgb +/- 1 standard deviation are: cynomolgus monkeys, 1.0526 +/- 0.0019 [males (n = 39), 1.0531 +/- 0.0017; females (n = 48), 1.0522 ... | 2001 | 11353523 |
| eeg delta activity during undisturbed sleep in the squirrel monkey. | the squirrel monkey (saimiri sciureus) exhibits a robust daily rhythm of sleep-wakefulness that is under circadian control, but the nature of homeostatic sleep regulation in this diurnal primate is poorly understood. since delta frequency (0.5-2.0 hz) activity in the electroencephalogram (eeg) during non-rapid eye movement (nrem) sleep is thought to reflect homeostatic factors contributing to sleep tendency, we measured eeg delta power density and slow wave incidence and amplitude during nrem sl ... | 2000 | 11382909 |
| immunogenicity and protective efficacy of recombinant human t-cell leukemia/lymphoma virus type 1 nyvac and naked dna vaccine candidates in squirrel monkeys (saimiri sciureus). | we assessed the immunogenicities and efficacies of two highly attenuated vaccinia virus-derived nyvac vaccine candidates encoding the human t-cell leukemia/lymphoma virus type 1 (htlv-1) env gene or both the env and gag genes in prime-boost pilot regimens in combination with naked dna expressing the htlv-1 envelope. three inoculations of nyvac htlv-1 env at 0, 1, and 3 months followed by a single inoculation of dna env at 9 months protected against intravenous challenge with htlv-1-infected cell ... | 2001 | 11390595 |
| a comparison of food preferences and nutrient composition in captive squirrel monkeys, saimiri sciureus, and pigtail macaques, macaca nemestrina. | i assessed the occurrence of food preferences in captive squirrel monkeys and pigtail macaques and analyzed whether their preferences correlate with nutrient composition. using a two-alternative choice test, i repeatedly presented six saimiri sciureus and six macaca nemestrina with all possible binary combinations of 12 types of food that are part of their diet in captivity. the two species exhibited significantly different rank orders of preference. correlational analyses revealed that the pref ... | 2001 | 11399302 |
| auditory frequency discrimination in the squirrel monkey. | four squirrel monkeys (saimiri sciureus) were tested for their frequency discrimination capacity using an eyeblink classical conditioning procedure, with air puff against the eye as unconditioned stimulus and 600-ms pure tones as conditioned stimuli. absolute frequency difference thresholds showed a minimum (20-41 hz, mean 30 hz) at 4,000-8,000 hz and increased towards higher as well as lower frequencies (70-90 hz, mean 80 hz at 300 hz; 44-120 hz, mean 82 hz at 16,000 hz). relative frequency dif ... | 2001 | 11401198 |
| horizontal transmission of toxoplasma gondii in squirrel monkeys (saimiri sciureus). | the possibility of horizontal transmission of t. gondii was examined in squirrel monkeys. after three monkeys were inoculated perorally with 1.1-2.1 x 10(3) cysts of the t. gondii me49, the animals were divided into two cages and maintained with one normal monkey for each cage as a cagemate. two out of the three t. gondii-inoculated monkeys died, and the remaining one monkey was sacrificed in a moribund state one week after infection because of acute toxoplasmosis. many t. gondii tachyzoites wer ... | 2001 | 11515092 |
| downregulation of p56(lck) tyrosine kinase activity in t cells of squirrel monkeys (saimiri sciureus) correlates with the nontransforming and apathogenic properties of herpesvirus saimiri in its natural host. | herpesvirus saimiri is capable of transforming t lymphocytes of various primate species to stable growth in culture. the interaction of the t-cellular tyrosine kinase p56(lck) with the transformation-associated viral protein tip has been shown before to activate the kinase and provides one model for the t-cell-specific transformation by herpesvirus saimiri subgroup c strains. in contrast to other primate species, squirrel monkeys (saimiri sciureus) are naturally infected with the virus without s ... | 2001 | 11533187 |
| the effects of feedback lighting on the circadian drinking rhythm in the diurnal new world primate saimiri sciureus. | feedback lighting provides illumination primarily during the subjective night (i.e., the photosensitive portion of the circadian cycle) in response to a given behavior. this technique has previously been used to test the nonparametric model of entrainment in nocturnal rodents. in three species (rattus norvegicus, mesocricetus auratus, and mus musculus), the free-running period of the locomotor activity rhythm was similar whether the animals were exposed to continuous light or discrete light pu ... | 1988 | 11539805 |
| effect of environmental enrichment devices on behaviors of single- and group-housed squirrel monkeys (saimiri sciureus). | squirrel monkeys display an interest in novel places, habituate to new situations, and spend most of their daily activity in the wild in large groups engaging in feeding behaviors over a broad area. captivity limits these behaviors and consequently may disrupt normal social organizations. in captivity, squirrel monkeys may exhibit stereotypical behaviors that are believed to indicate decreased psychologic well-being. when a monkey's behavior can be made to approach that seen in the wild, and ste ... | 1997 | 11541211 |
| training squirrel monkeys (saimiri sciureus) to deceive: acquisition and analysis of behavior toward cooperative and competitive trainers. | three squirrel monkeys (saimiri sciureus) learned to reach toward a container that covered food if a cooperative trainer rewarded such reaches by giving the food. a competitive trainer kept any food found, but wrong selections by this trainer were also rewarded. the monkeys initially reached toward the baited container indiscriminately, but gradually and with the aid of color-cued containers, all 3 reliably reached "honestly" and "deceptively" in the presence of the cooperative and competitive t ... | 2001 | 11594497 |
| fine-scale organization of si (area 3b) in the squirrel monkey revealed with intrinsic optical imaging. | optical imaging of intrinsic cortical activity was used to study the somatotopic map and the representation of pressure, flutter, and vibration in area 3b of the squirrel monkey (saimiri sciureus) cortex under pentothal or isoflurane anesthesia. the representation of the fingerpads in primary somatosensory cortex was investigated by stimulating the glabrous skin of distal fingerpads (d1-d5) with teflon probes (3-mm diam) attached through an armature to force feedback-controlled torque motors. un ... | 2001 | 11731557 |
| telomere biology and cellular aging in nonhuman primate cells. | to determine how cellular aging is conserved among primates, we analyzed the replicative potential and telomere shortening in skin fibroblasts of anthropoids and prosimians. the average telomere length of the new world primates ateles geoffroyi (spider monkey) and saimiri sciureus (squirrel monkey) and the old world primates macaca mulatta (rhesus monkey), pongo pygmaeus (orangutan), and pan paniscus (pigmy chimpanzee) ranged from 4 to 16 kb. we found that telomere shortening limits the replicat ... | 2002 | 11777339 |
| the suppressive effect of dexamethasone on the proliferation of plasmodium falciparum in squirrel monkeys. | we investigated the effects of dexamethasone (dx) on the proliferation of plasmodium falciparum indochina-i/cdc in squirrel monkeys (saimiri sciureus boliviensis). three splenectomized squirrel monkeys each received 16 perioral dx doses (three times per week for 36 days), at three different dosages (0.2, 0.5, and 2.0 mg/ kg). each monkey was intravenously inoculated with 7.8 x 10(7) red blood cells infected with p. falciparum 1 week after the initiation of dx treatment. parasite growth was suppr ... | 2002 | 11822737 |
| molecular cytotaxonomy of new world monkeys (platyrrhini) - comparative analysis of five species by multi-color chromosome painting gives evidence for a classification of callimico goeldii within the family of callitrichidae. | chromosome rearrangements are considered as "rare genomic changes" and can provide useful markers and even landmarks for reconstructing phylogenies complementary to dna sequence data and bio-morphological comparisons. here, we applied multi-directional chromosome painting to reconstruct the chromosome phylogeny and evolutionary relationships among the new world monkey (platyrrhini) species callithrix argentata, cebuella pygmaea, saguinus oedipus, callithrix jacchus and callimico goeldii. the res ... | 2001 | 11856883 |
| cortical synaptic arrangements of the third visual pathway in three primate species: macaca mulatta, saimiri sciureus, and aotus trivirgatus. | the koniocellular (k) pathway is one of three pathways from the lateral geniculate nucleus (lgn) to primate visual cortex (v1). k pathway projections to the cytochrome oxidase (co) blobs of v1 suggest involvement in chromatic processing given reports that the co blobs in diurnal primates contain cells selective for color. k lgn layers and co blobs, however, are also well developed in nocturnal primates such as owl monkeys, which are likely to be color blind. thus, the k pathway plays either diff ... | 2002 | 11923453 |
| molecular cloning, characterization, and quantification of squirrel monkey ( saimiri sciureus) th1 and th2 cytokines. | primates have long been used as models to study the basic mechanisms of human disease. the squirrel monkey, saimiri sciureus,is a new world monkey that can be satisfactorily bred in captivity and infected with various human pathogens. the basic immunological parameters of squirrel monkeys, including immunoglobulin subclasses and markers for lymphocyte subsets, have already been characterized. however, immunological reagents and assays specific for the detection and quantification of squirrel mon ... | 2002 | 11976788 |
| olfactory sensitivity for aliphatic alcohols in squirrel monkeys and pigtail macaques. | the view that primates are microsmatic animals is based mainly on an interpretation of neuroanatomical features, whereas physiological evidence of a poorly developed sense of smell in this order of mammals is largely lacking. using a conditioning paradigm, we therefore assessed the olfactory sensitivity of three squirrel monkeys (saimiri sciureus) and of four pigtail macaques (macaca nemestrina) for a homologous series of aliphatic alcohols (ethanol to 1-octanol) and isomeric forms of some of th ... | 2002 | 12000808 |
| working memory of action: a comparative study of ability to selecting response based on previous action in new world monkeys (saimiri sciureus and callithrix jacchus). | working memory of the outcome of one's own action is important for organizing and learning appropriate behaviors in a given condition. to examine whether non-human primates with different neocortical sizes show different abilities regarding working memory for action, the performance of squirrel monkeys (saimiri sciureus) and common marmosets (callithrix jacchus) in a kind of delayed-response task was compared. in this task, subjects were required to select a response based on short-term memory o ... | 2002 | 12044691 |
| arboreal locomotion in small new-world monkeys. | the postural and locomotor activity and its relation to substrates was observed in 3 saguinus oedipus, and 3 saimiri sciureus for comparison, during a period of 10 h for each individual. the animals moved freely in cages of 3.40 m x 3.40 m x 2.40 m (height) on rather diverse substrates. observations were made according to the focal-animal-method, with combined instantaneous and continuous sampling. they were protocoled in schematic form and video-recorded. in addition, 3 further saguinus oedipus ... | 2002 | 12050896 |
| the putative haemobartonella that influences plasmodium falciparum parasitaemia in squirrel monkeys is a haemotrophic mycoplasma. | splenectomised squirrel monkeys (saimiri sciureus) are increasingly being used as an experimental host for human malaria studies, notably for the assessment of candidate vaccines against plasmodium falciparum blood-stage infection. recently, s. sciureus monkeys in our primate-breeding colony were reported to be asymptomatic carriers of a putative haemobartonella species. patent haemobartonella infection is frequently activated following splenectomy, and may interfere with studies on the course o ... | 2002 | 12067828 |
| complementary distribution of calbindin d-28k and parvalbumin in the basal forebrain and midbrain of the squirrel monkey. | the distribution of cell bodies expressing either calbindin d-28k or parvalbumin immunoreactivity in the basal forebrain and midbrain of squirrel monkeys (saimiri sciureus) was studied on contiguous sections incubated with monoclonal antibodies raised against calbindin or parvalbumin. in the nucleus accumbens, medium-sized calbindin-positive neurons formed two cell bridges joining the ventral part of the striatum to the olfactory tubercle, whereas medium-sized parvalbumin-positive cells in the s ... | 1991 | 12106229 |
| excretion and measurement of estradiol and progesterone metabolites in the feces and urine of female squirrel monkeys (saimiri sciureus). | the first objective of the present study was to determine the metabolic form and rate of excretion of ovarian hormone metabolites in the urine and feces of female squirrel monkeys injected with radiolabeled progesterone (po) and estradiol. the major portion of the urinary metabolites of both hormones was excreted within 16-24 hr post-injection. estrogen and po isotopes in feces exhibited an excretion peak at 16 hr post-injection. the majority of recovered radiolabel of both hormones was excreted ... | 2002 | 12111683 |
| housing and care of monkeys and apes in laboratories: adaptations allowing essential species-specific behaviour. | during the last two decades an increasing amount of attention has been paid to the housing and care of monkeys and apes in laboratories, as has been done with the housing and care of other categories of captive animals. the purpose of this review is to develop recommendations for adaptations of housing and care from our knowledge of the daily behavioural activity of monkeys and apes in natural conditions and in enriched laboratory conditions. this review deals mainly with adaptations of daily ho ... | 2002 | 12144737 |
| proliferating cells can differentiate into neurons in the striatum of normal adult monkey. | in this study we used bromodeoxyuridine (brdu), a thymidine analogue that is incorporated into the dna of mitotic cells, to study the cytogenesis status of the striatum in normal, adult, squirrel monkeys (saimiri sciureus). three weeks following brdu injection, numerous brdu-labeled (+) cells were encountered within both the dorsal and the ventral striatum, including the nucleus accumbens. their number ranged from 5 to 50 per 40 microm-thick section. these brdu+ cells were more abundant medially ... | 2002 | 12147309 |
| newly generated neurons in the amygdala and adjoining cortex of adult primates. | the subventricular zone remains mitotically active throughout life in rodents. studies with tritiated thymidine, which is incorporated into the dna of mitotic cells, have revealed that the rodent subventricular zone produces neuroblasts that migrate toward the olfactory bulb along the rostral migratory stream. a similar migratory stream has been documented in monkeys by using the thymidine analogue brdurd. the same approach showed that neurogenesis occurred in the dentate gyrus of adult primates ... | 2002 | 12177450 |
| abo blood groups in the primate species of cebidae from the amazon region. | the abo blood groups were determined in blood and saliva collected from 40 aotus infulatus, 74 saimiri sciureus, and 96 cebus apella from the amazonian region along the tocantins river. saliva samples were tested for human abh antigens by a standard hemagglutination inhibition test. aotus infulatus showed monomorphism, exhibiting only the b blood group. saimiri sciureus exhibited the a (67) and ab (7) phenotypes. all four phenotypes have been found in c. apella: o (8), a (52), b (19) and ab (17) ... | 2002 | 12190854 |
| pulvinar and other subcortical connections of dorsolateral visual cortex in monkeys. | the present study used injections of neuroanatomical tracers to determine the subcortical connections of the caudal and rostral subdivisions of the dorsolateral area (dl) and the middle temporal crescent area (mt(c)) in owl monkeys (aotus trivirgatus), squirrel monkeys (saimiri sciureus), and macaque monkeys (macaca fascicularis and m. radiata). emphasis was on connections with the pulvinar. patterns of corticopulvinar connections were related to subdivisions of the inferior pulvinar (pi) define ... | 2002 | 12209852 |
| a study of the central control of vocalization using the squirrel monkey. | in the squirrel monkey (saimiri sciureus), the electrical activity of single neurones was compared in the periaqueductal grey of the midbrain and the reticular formation of the medulla oblongata during vocalization, using a recently developed telemetric technique. the results show that both structures contain neurones with vocalization-correlated activity. there are characteristic differences between the two structures, however. neurones showing changes in discharge rate with changes in fundamen ... | 2002 | 12237042 |
| experience-dependent asymmetric variation in primate prefrontal morphology. | theories of human development suggest that experiences embedded in social relationships alter prefrontal brain systems that mediate emotional self-regulation. this study tests for experience-dependent effects on prefrontal gray and white matter volumes determined in 39 young adult monkeys (saimiri sciureus) 4 years after conditions that modified early maternal availability. these conditions were previously shown to alter subsequent measures of emotional behavior, social propensities, and hypotha ... | 2002 | 12385789 |
| evolutionary history of chromosome 10 in primates. | we have tracked the evolutionary history of chromosomes homologous to hsa10 (phyl-10) in primates using appropriate panels of pcp, yac, and bac probes. this approach allowed us to delineate more precisely the phyl-10 constitution in the ancestor of catarrhine, platyrrhine, and prosimians. the results suggest that (i) in the ancestor of prosimians phyl-10 was organized in two separate phyl-10p and phyl-10q chromosomes; (ii) in the progenitor of new world monkeys phyl-10p was a separate chromosome ... | 2002 | 12424526 |
| 2-deoxyglucose uptake during vocalization in the squirrel monkey brain. | in the squirrel monkey (saimiri sciureus), the cerebral 2-deoxyglucose uptake was compared between animals made to vocalize by electrical stimulation of the periaqueductal grey and animals stimulated in the same structure, but sub-threshold for vocalization. a significantly higher 2-deoxyglucose uptake in the vocalizers than the non-vocalizers was found in the dorsolateral prefrontal cortex, supplementary and pre-supplementary motor area, anterior and posterior cingulate cortex, primary motor co ... | 2002 | 12429422 |
| the rostral migratory stream in adult squirrel monkeys: contribution of new neurons to the olfactory tubercle and involvement of the antiapoptotic protein bcl-2. | the subventricular zone (svz) lying along the ependymal layer of lateral ventricle is known to generate neural progenitor cells throughout adulthood in specific areas of the mammalian brain. in rodents, the anterior region of the svz produces neuroblasts that migrate in chain toward the olfactory bulb along the so-called rostral migratory stream (rms). in the present study, the organization of the rms in a representative of new world primates - the squirrel monkey (saimiri sciureus) - was studie ... | 2002 | 12453055 |
| periorbital mass in a squirrel monkey (saimiri sciureus). | during a routine annual physical examination, a small, hard, palpable mass was discovered on the left cheek below the lateral canthus of the eye of an adult male squirrel monkey (saimiri sciureus). radiographs of the lesion were obtained, and the lesion was surgically removed. histologic examination of the mass was performed. on the basis of radiographic, anatomic, and histologic findings, a diagnosis of osteoma was made. | 1998 | 12456145 |
| modeling of plasmodium falciparum-infected erythrocyte cytoadhesion in microvascular conditions: chondroitin-4-sulfate binding, a competitive phenotype. | although chondroitin-4-sulfate (csa) is expressed throughout the microvasculature and csa-binding infected erythrocytes (ie(csa)) cytoadhere to lung and brain endothelial cells and sequester in male saimiri sciureus, this phenotype seems to be dependent on the presence of a placenta to develop. this contradiction was investigated by modeling the interactions and cytoadhesion parameters in the microvasculature. mixtures of ies interacting with csa, cd36, or intercellular adhesion molecule 1 were ... | 2003 | 12552454 |
| sequencing and analysis of genomic dna and cdna encoding tnf-alpha in the squirrel monkey (saimiri sciureus). | if a number of cytokines and growth factors that have been characterized from human cells were investigated in non-human primates, results from such approaches would allow the development of assays to detect and quantitate cytokines in experimental models. tumor necrosis factor-alpha (tnf-alpha) is an important pluripotent cytokine which plays a crucial role in host defense. as yet, no complete molecular data have been reported for the squirrel monkey tnf-alpha. polymerase chain reaction (pcr) p ... | 2003 | 12628762 |
| spatial memory performance of freely-moving squirrel monkeys. | few experiments have addressed the problem of cognitive map formation in non-human primates. therefore, a paradigm was developed to assess spatial memory formation in squirrel monkeys (saimiri sciureus) moving freely in three dimensions. while moving on the walls and floor of a large test chamber, the animals learned to collect pieces of cereal from baited food-ports interspersed among non-baited ports. the cereal-pellets were not visible to the monkeys, so the animals needed to develop spatial ... | 2003 | 12644290 |
| rflp analysis of mtdna from six platyrrhine genera: phylogenetic inferences. | this study investigates the phylogenetic relationships of 10 species of platyrrhine primates using rflp analysis of mtdna. three restriction enzymes were used to determine the restriction site haplotypes for a total of 276 individuals. phylogenetic analysis using maximum parsimony was employed to construct phylogenetic trees. we found close phylogenetic relationships between alouatta, lagothrix and ateles. we also found a close relationship between cebus and aotus, with saimiri clustering with t ... | 2003 | 12759493 |
| responses of squirrel monkeys to their experimentally modified mobbing calls. | previous acoustic analyses suggested emotion-correlated changes in the acoustic structure of squirrel monkey (saimiri sciureus) vocalizations. specifically, calls given in aversive contexts were characterized by an upward shift in frequencies, often accompanied by an increase in amplitude. in order to test whether changes in frequencies or amplitude are indeed relevant for conspecific listeners, playback experiments were conducted in which either frequencies or amplitude of mobbing calls were mo ... | 2003 | 12765410 |
| noninvasive technique for the repeated sampling of salivary free cortisol in awake, unrestrained squirrel monkeys. | the use of noninvasive measures of hypothalamic-pituitary-adrenal (hpa) axis function is of growing interest among preclinical and clinical investigators. this report describes a method for the repeated assessment of salivary free cortisol in awake, unrestrained squirrel monkeys (saimiri sciureus) based on a saliva sampling technique previously developed for rhesus monkeys. individually housed adult male squirrel monkeys were trained to chew on dental rope attached to a pole, from which saliva w ... | 2003 | 12784287 |
| immunization with recombinant duffy binding-like-gamma3 induces pan-reactive and adhesion-blocking antibodies against placental chondroitin sulfate a-binding plasmodium falciparum parasites. | maternal malaria is associated with the sequestration, in the placenta, of plasmodium falciparum-infected erythrocytes onto chondroitin sulfate a (csa), via the duffy binding-like (dbl)-gamma3 domain of the p. falciparum erythrocyte membrane protein 1 (pfemp1(csa)) (dbl-gamma3(csa)). the production of antibodies against csa-binding infected erythrocytes (ies(csa)) is correlated with resistance to maternal malaria in multiparous women. we produced recombinant dbl-gamma3(csa) (rdbl-gamma3(csa)) in ... | 2003 | 12825185 |
| diet of a free-ranging group of squirrel monkeys (saimiri sciureus) in eastern brazilian amazonia. | the feeding behaviour of free-ranging saimiri sciureus was monitored over a 6-month period in eastern brazilian amazonia. behavioural data were collected in scan samples (7-9 days per month), and fruit and arthropod availability were recorded monthly. a total of 3,546 feeding records were collected, divided between reproductive plant parts (55.1%) and arthropods (44.9%). the majority of identified prey were orthopterans and lepidopterans, and 10 of the 23 plant species exploited were leguminosae ... | 2003 | 12826734 |
| neuronal activity in the inferior colliculus and bordering structures during vocalization in the squirrel monkey. | in four squirrel monkeys (saimiri sciureus), the inferior colliculus, together with the neighboring superior colliculus, reticular formation, cuneiform nucleus and parabrachial area, were explored with microelectrodes, looking for neurons that might be involved in the discrimination between self-produced and external sounds. vocalization was elicited by kainic acid injections into the periaqueductal gray of the midbrain. acoustic tests were carried out with ascending and descending narrow-band n ... | 2003 | 12850582 |
| numerity of a socially housed hamadryas baboon (papio hamadryas) and a socially housed squirrel monkey (saimiri sciureus). | to extend a study conducted by e. m. brannon and h. s. terrace (1998, 2000), the authors trained 1 hamadryas baboon (papio hamadryas) and 1 squirrel monkey (saimiri sciureus) to respond to stimuli representing the numerosities 1-4 in ascending order. when tested with novel stimuli of the same numerosities, both subjects' performance appeared to be based on the numerical attributes of stimuli. subjects were then tested on their ability to order pairs of numerosities derived from the values 1-9. b ... | 2003 | 12856792 |
| liver desaturase activities and fa composition in monkeys. effect of a low-protein diet. | the aim of the present study was to measure delta9-, delta6-, and delta5-desaturase activities in liver microsomes, as well as phospholipid fa composition of liver and erythrocytes in monkeys fed a control or low-protein diet during the postweaning period. ten saimiri sciureus boliviensis (cebidae) of both sexes were employed; at 12 mon of age they were separated into two groups fed ad libitum on a control or a low-protein diet for 24 mon. saimiri sciureus had active delta9, delta6, and delta5 l ... | 2003 | 12880108 |