Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| sporozoite-induced infections of the salvador i strain of plasmodium vivax in saimiri sciureus boliviensis monkeys. | twenty saimiri sciureus boliviensis monkeys from bolivia were inoculated intravenously with sporozoites of the salvador i strain of plasmodium vivax. all animals were splenectomized 7 days after inoculation. inoculation of 100,000 sporozoites resulted in prepatent periods averaging 16.6 days; all monkeys developed high-level parasitemias with an average maximum of 103,000 per mm3. inoculation of 10,000 sporozoites resulted in average prepatent periods of 19.4 days; one of the resulting infection ... | 1988 | 3294366 |
| distribution and morphological characteristics of dopamine-immunoreactive neurons in the midbrain of the squirrel monkey (saimiri sciureus). | the distribution and morphological characteristics of dopamine (da) neurons in the midbrain of the squirrel monkey (saimiri sciureus) were investigated by peroxidase-antiperoxidase (pap) immunohistochemistry with a highly specific antiserum raised against da-glutaraldehyde-lysyl-protein conjugate (donated by m. geffard). four contiguous areas contained da-immunostained nerve cell bodies: (1) the substantia nigra, pars compacta (snc), (2) the ventral tegmental area (vta), (3) the retrorubral area ... | 1988 | 3346372 |
| anatomical connections of the prepositus and abducens nuclei in the squirrel monkey. | the primary goal of this investigation was to identify the areas of the brainstem and cerebellum that provide afferent projections to the nucleus prepositus hypoglossi in primates. after horseradish peroxidase conjugated to wheat germ agglutinin (wga-hrp) was injected into the prepositus in squirrel monkeys (saimiri sciureus), the largest populations of retrogradely labeled neurons were found in the vestibular nuclei, the contralateral perihypoglossal nuclei, and the medullary and pontine reticu ... | 1988 | 3346381 |
| the nasotemporal division in primate retina: the neural bases of macular sparing and splitting. | in primates, each hemisphere contains a representation of the contralateral visual hemifield; unilateral damage to the visual pathways results in loss of vision in half of the visual field. apparently similar severe, unilateral lesions to the central visual pathways can result in two qualitatively different central visual field defects termed macular sparing and macular splitting. in macular sparing a 2 degrees to 3 degrees region around the fovea is spared from the effects of unilateral damage ... | 1988 | 3353708 |
| transmission of the os strain of plasmodium inui to saimiri sciureus boliviensis and aotus azarae boliviensis monkeys by anopheles dirus mosquitoes. | eight saimiri and 7 aotus monkeys were exposed to infection with the os strain of plasmodium inui via the bites of from 2 to 7 anopheles dirus mosquitoes. all saimiri monkeys developed high-level infections of from 152,000 to 500,000/mm3 after prepatent periods of from 14 to 17 days. only 1 aotus monkey developed a patent infection after a period of 28 days. feeding on these animals failed to result in infection of an. dirus mosquitoes. | 1988 | 3379532 |
| plasma lipoprotein alterations in squirrel monkeys (saimiri sciureus) during ethanol administration and abstinence. | the time course of lipoprotein changes during ethanol (etoh) consumption followed by abstinence was examined in 3 groups of male squirrel monkeys: 1) controls fed isocaloric liquid diet; 2) low etoh monkeys given liquid diet with vodka substituted isocalorically for carbohydrate at 12% of calories; and 3) high etoh animals fed diet plus vodka at 24% of calories. after 2 weeks, high etoh monkeys showed significant elevations in total plasma cholesterol which continued to increase at 4 weeks and t ... | 1988 | 3401294 |
| prehension in cebus and saimiri: i. grip type and hand preference. | prehension was examined in tufted capuchins (cebus apella) and squirrel monkeys (saimiri sciureus). individual subjects were videotaped from frontal and sagittal planes while they grasped small objects presented in several ways (in view, out of view, embedded, moving). capuchins used a precision grip in 30% of trials and in more than half of trials with stationary objects. most (54%) of the precision grips used were opposition of the thumb to the index finger; however, eight other forms were als ... | 1988 | 31968893 |
| 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 |
| immunohistochemical localization of gabaa receptors in the retina of the new world primate saimiri sciureus. | a large population of amacrine cells in the retina are thought to use gaba as an inhibitory neurotransmitter in their synaptic interactions within the inner plexiform layer. however, little is known about their synaptic targets; the neurons that express the receptors for gaba have not been clearly identified. recently, the gabaa receptor has been isolated and antibodies have been raised against it. these antibodies have proven useful for the immunocytochemical localization of the receptor, and t ... | 1989 | 2562111 |
| a two-site sandwich immunoradiometric assay of squirrel monkey (saimiri sciureus) igm using monoclonal antibodies. | nine hybrid clones secreting antibodies to squirrel monkey (saimiri sciureus) igm were produced and two of these (1f1g5 and 5h11b3) were selected for further studies. these non-precipitating monoclonal antibodies reacted with two distinct repetitive antigenic determinants, probably of the conformational type, only present on the native or sds-denatured igm molecule. reduction of the pentamer with 2-mercaptoethanol led to complete destruction of the corresponding epitopes. 1f1g5 antibodies from a ... | 1989 | 2926146 |
| selective degeneration of the parvocellular-projecting retinal ganglion cells in a new world monkey, saimiri sciureus. | selective degeneration of retinal ganglion cells projecting to parvocellular layers of the dorsal lateral geniculate nucleus (lgn) was observed in squirrel monkeys (saimiri sciureus) exposed to a range of doses of acrylamide monomer. similar acrylamide-induced neuronal loss has previously been reported in parvocellular-projecting ganglion cells of macaques, but no such selective degeneration has been found in acrylamide-dosed rats, squirrels, rabbits or cats. the extent of ganglion cell loss obs ... | 1989 | 2478261 |
| brain-stem auditory evoked potentials in squirrel monkey (saimiri sciureus). | to more fully characterize brain-stem auditory evoked potentials (baeps) in non-human primates, baeps were recorded from chronically implanted epidural electrodes in 10 squirrel monkeys (saimiri sciureus). the effects of stimulus intensity, repetition rate, and anesthesia (ketamine 20 mg/kg i.m.) on peak latencies and inter-peak intervals were evaluated. monkey wave forms consisted of approximately 7 peaks (i-vii), each exhibiting similar latencies across sessions, with later peaks exhibiting gr ... | 1989 | 2480887 |
| serologic evidence of encephalitozoon cuniculi infection in a colony of squirrel monkeys (saimiri sciureus). | five hundred seventeen serum samples obtained during 3 years from a collection of 250 squirrel monkeys were examined by indirect immunofluorescence and dot-elisa for antibodies to encephalitozoon cuniculi. one hundred seventy-nine monkeys were positive at least once and fifty six monkeys were positive three or more times. older animals were more likely to be positive than young animals, but the proportion of serologically positive monkeys did not change appreciably over the 3 years. as judged by ... | 1989 | 2503661 |
| differences in mineral metabolism among nonhuman primates receiving diets with only vitamin d3 or only vitamin d2. | we tested for differences in aspects of mineral metabolism during the administration of diets with only vitamin d3 or only vitamin d2 in four nonhuman anthropoid primate species [two catarrhini, macaca fascicularis (crab-eating macaque) and macaca mulatta (rhesus macaque), and two platyrrhini, saimiri sciureus (squirrel monkey) and aotus vociferans (night monkey)]. all four species maintained approximately 2- to 3-fold higher serum 25-hydroxyvitamin d (25ohd) level while receiving vitamin d3 tha ... | 1989 | 2555385 |
| effects of locus coeruleus lesions on auditory, long-latency, event-related potentials in monkey. | it has previously been demonstrated that monkeys exhibit certain event-related potential (erp) components showing latency, polarity, and contingency similarities to those observed in humans. in the present study, monkey p300-like components were studied in order to evaluate the hypothesis that the noradrenergic locus coeruleus (lc) system participates in their generation or modulation. erps were recorded from untrained squirrel monkeys (saimiri sciureus) twice a week for 4 weeks before and after ... | 1989 | 2563282 |
| evidence for a distinct nigropallidal dopaminergic projection in the squirrel monkey. | injections of the retrograde fluorescent tracer fast blue in the striatum (str) and nuclear yellow in the internal segment of the globus pallidus (gpi) in the squirrel monkey (saimiri sciureus) revealed a nigropallidal projection whose cellular origin was largely distinct from that of the nigrostriatal pathway. neurons containing the tracer injected in gpi were scattered throughout the substantia nigra-ventral tegmental area complex where they formed approximately 20-25% of the total number of r ... | 1989 | 2565144 |
| dopaminergic innervation of the basal ganglia in the squirrel monkey as revealed by tyrosine hydroxylase immunohistochemistry. | the organization of the dopaminergic mesostriatal fibers and their patterns of innervation of the basal ganglia in the squirrel monkey (saimiri sciureus) were studied immunohistochemically with an antiserum raised against tyrosine hydroxylase (th). numerous fibers arose from midbrain th-positive cell bodies of the substantia nigra pars compacta (group a9), the retrorubral area (group a8), and the lateral portion of the ventral tegmental area (group a10). these fibers accumulated dorsomedially to ... | 1989 | 2572613 |
| bilirubin excretion and bile flow in fed and fasted brazilian squirrel monkeys (saimiri sciureus). | fasted brazilian squirrel monkeys (brsms) exhibited slightly higher serum bilirubin levels (0.30 +/- 0.05 mg/dl) than others in the fed state (0.13 +/- 0.01). the mean liver weight was 50% lower following a 22 h fast. the rate of bile flow was unaffected by fasting and averaged 13.8 microliters/min/kg and 47.5 microliters/min/100g liver in six brsms. no significant difference in mean bilirubin excretion/min was observed on a body weight basis following fasting. when the mean rate of bilirubin ex ... | 1989 | 2588480 |
| behavioral and endocrine consequences of heterosexual pair formation in squirrel monkeys. | the south american squirrel monkey (saimiri sciureus) typically lives in large social groups containing several individuals of all age/sex categories. when living in established heterosexual pairs, reproduction in this seasonally breeding primate is poor. we attempted to induce breeding activity in pair-housed monkeys by forming new heterosexual pairs just prior to the breeding season. breeding readiness, as reflected in behavior and gonadal hormones, was induced in males, but not in females. ma ... | 1989 | 2602484 |
| location of respiratory motoneurons involved in phonation. an hrp study in the squirrel monkey. | in 11 squirrel monkeys (saimiri sciureus) the motoneuronal distribution of those muscles being involved in the respiratory component of phonation, that is the mm. obliquus externus and internus, rectus and transversus abdominis, intercostalis externus and internus, and intercartilagineus, were studied with the horseradish peroxidase retrograde tracing technique. it was found that the spinal representations of the abdominal muscles overlap to a large extent. motoneurons of all four abdominal musc ... | 1989 | 2607132 |
| corticotropin-releasing factor immunoreactivity in monkey neocortex: an immunohistochemical analysis. | corticotropin-releasing factor (crf) has been implicated in the pathophysiology of certain human neuropsychiatric disorders that affect neocortical function. however, the anatomical organization of crf-containing structures in the expanded and highly differentiated primate neocortex has not been previously described. in this study, the distribution of crf-immunoreactive neurons and processes was characterized in the neocortex of new world squirrel monkeys (saimiri sciureus). substantial regional ... | 1989 | 2613945 |
| effect of varying dosages and adjuvants on antibody response in squirrel monkeys (saimiri sciureus) immunized with the porcine zona pellucida mr = 55,000 glycoprotein (zp3). | using the porcine zona pellucida mr = 55,000 (zp3) glycoprotein as immunogen, the effect of varying zp3 dosages (50 micrograms, 25 micrograms, 5 micrograms) or adjuvants (200 micrograms zp3 with either freund's, a1[oh]3, or a muramyl dipeptide analog [mdp] on antibody response was evaluated in female squirrel monkeys. although the dosage range investigated did result in dose-dependent titration profiles, antisera from all dosage groups demonstrated in vitro contraceptive potential. mdp was as ef ... | 1989 | 2619883 |
| peripheral blood mononuclear cells in the squirrel monkey saimiri sciureus: characterization and functional aspects of t lymphocytes. | characterization and functional aspects of squirrel monkey peripheral blood mononuclear cells (pbmc), and mainly t cells, are described in the present paper; this should enable the study of cellular immune responses in an experimental model for malaria. pbmc were obtained from ficoll-hypaque gradient separation and fractionated into t cells and non-t cells by means of e-rosetting techniques and adherence to plastic dishes. pbmc subset phenotypes were characterized by means of monoclonal antibodi ... | 1989 | 2629039 |
| the uganda i/cdc strain of plasmodium malariae in saimiri sciureus boliviensis. | the uganda i/cdc strain of plasmodium malariae, initially adapted to monkeys of the genus aotus, was studied in splenectomized saimiri sciureus boliviensis. mean maximum parasitemia ranged from 248 to 22,134/mm3. only 1 mosquito was infected of 2,238 examined. after the parasite was adapted to this host, infections were characterized by periods of detectable parasitemia extending up to 269 days and by sustained periods when parasite counts were greater than 1,000/mm3. after 4 linear passages, th ... | 1989 | 2647957 |
| immunization of saimiri sciureus boliviensis with recombinant vaccines based on the circumsporozoite protein of plasmodium vivax. | we report a trial in squirrel monkeys of 2 recombinant plasmodium vivax malaria vaccine candidates based on the circumsporozoite (cs) protein. one recombinant (nsl81v20), produced in escherichia coli, contains the repeat region of the cs protein. the other (vivax-1) recombinant is yeast-derived and contains the entire repeat domain and part of the surrounding n-terminal and c-terminal regions. both antigens were administered with alum and muramyl tripeptide as adjuvants. no formulations caused t ... | 1989 | 2658634 |
| open-loop and closed-loop optokinetic nystagmus in squirrel monkeys (saimiri sciureus) and in man. | horizontal optokinetic nystagmus (okn) was measured in 3 normal squirrel monkeys by means of the electromagnetic search coil technique. binocular and monocular stimulation of each eye to the left and right by moving vertical stripe patterns of 2.37 or 15 degree period were applied at angular velocities of 0.5 to 400 deg/s. after measurement of horizontal okn under normal conditions, open-loop okn gain was determined by monocular stimulation of an eyeball immobilized by means of retrobulbar injec ... | 1989 | 2699364 |
| intestinal trichomonads (tritrichomonas mobilensis) in the natural host saimiri sciureus and saimiri boliviensis. | a retrospective study of cecal and colonic tissues from 28 squirrel monkeys (saimiri sciureus and saimiri boliviensis) demonstrated enteric trichomonads within luminal crypts. twenty-one of 28 (75%) had trichomonads in the mucosal epithelium either in cup-like depressions or intraepithelial vacuoles. organisms were also beneath the superficial luminal mucosal epithelium and between the basement membrane and crypt epithelial cells. immunoperoxidase staining also identified organisms within the la ... | 1989 | 2711571 |
| noradrenergic innervation of monkey prefrontal cortex: a dopamine-beta-hydroxylase immunohistochemical study. | norepinephrine has been implicated in the regulation of a number of cortical functions, yet relatively little is known about the anatomical organization of noradrenergic axons in the expanded and highly differentiated prefrontal cortex of primates. in this study, the distribution of fibers containing dopamine-beta-hydroxylase (dbh), the enzyme that converts dopamine to norepinephrine, was characterized immunohistochemically in the prefrontal cortical regions of old world cynomolgus monkeys (maca ... | 1989 | 2715385 |
| sustained azoospermia in squirrel monkey, saimiri sciureus, resulting from a single intratesticular glycerol injection. | previous studies in rats had shown that a single intratesticular injection of glycerol resulted in long-term suppression of spermatogenesis without marked alterations in hormone levels. studies were undertaken to determine the effect of similar treatment in squirrel monkeys (saimiri sciureus). ten monkeys received an intratesticular injection of saline (controls) and ten of glycerol solution (treated). semen and blood samples were obtained on a weekly or bi-weekly basis one month prior to, durin ... | 1989 | 2721196 |
| modulation of colonization by black-pigmented bacteroides species in squirrel monkeys by immunization with bacteroides gingivalis. | periodontal diseases are inflammatory responses thought to be triggered by specific microorganisms colonizing in the gingival crevice. theoretically, periodontal diseases could be prevented if the etiologic organisms were not allowed to colonize the subgingival area. the humoral immune response is one mechanism which may modulate bacterial colonization in the gingival crevice. to test the effect of systemic humoral immunity on subgingival colonization by bacteria, squirrel monkeys (saimiri sciur ... | 1989 | 2744849 |
| species-dependent differences in atp half-life of glucose deprived crystalline lens. | 1. significant differences were detected by 31p nmr spectroscopic techniques in the intrinsic rate of atp hydrolysis by crystalline lenses from adult macaca mulatta, saimiri sciureus, felis catus, sus, canis familiaris, cavia rodentia and oryctalagis cuniculus during exogenous glucose deprivation. 2. these differences were not attributable to differences in endogenous glycogen stores, and appear instead to emanate from comparative species differences in lenticular enzyme activities. | 1989 | 2758799 |
| extrinsic determinants of retinal ganglion cell development in primates. | as in all mammals studied to date, primate retina contains morphologically distinct classes of retinal ganglion cells (polyak: the retina. chicago: university of chicago press, '41; boycott and dowling: philos. trans. r. soc. lond. [biol.] 225:109-184, '69; leventhal et al.: science 213:1139-1142, '81; perry et al.: neuroscience 12:1101-1123, '84; rodieck et al.: j. comp. neurol. 233:115-132, '85; rodieck: in h.d. steklis and j. erwin (eds): comparative primate biology, volume 4: neurosciences. ... | 1989 | 2794114 |
| on the a. malaris of the common squirrel monkey (saimiri sciureus). | detailed observations were made of the a. malaris in 11 adult common squirrel monkeys (saimiri sciureus) utilizing the plastic injection method. the malar artery was well-developed in all 21 examples observed and arose medially from the infraorbital artery proximal to the entrance of the infraorbital canal and lateral to the obliquus inferior muscle. the a. malaris passed superomedially outside the periorbita on the orbital surface of the maxilla and curved medially in front of the muscle, where ... | 1989 | 2812675 |
| evidence for interconnections between the two segments of the globus pallidus in primates: a pha-l anterograde tracing study. | small injections of the lectin phaseolus vulgaris-leucoagglutinin (pha-l) in the external segment of the pallidum (gpe) in the squirrel monkey (saimiri sciureus) and in the rhesus monkey (macaca mulatta) led to anterograde labeling of fibers in the internal segment of the pallidum (gpi). these fibers formed numerous large varicosities reminiscent of terminal boutons, which closely surrounded gpi cell bodies and primary dendrites. conversely, pha-l injections in the gpi of squirrel monkeys produc ... | 1990 | 2085730 |
| testing of plasmodium vivax cs proteins in saimiri monkeys. | recombinant proteins directed against the circumsporozoite (cs) protein of plasmodium vivax were tested for safety, immunogenicity, and efficacy in saimiri sciureus boliviensis monkeys. the monkeys were immunized 3 times with either alum or muramyl tripeptide as adjuvant, and were challenged with 10,000 sporozoites (p. vivax, salvador i strain) from mosquitos infected by membrane feeding on gametocytes from chimpanzees. antibodies, measured by indirect immunofluorescent antibody tests and enzyme ... | 1990 | 2094590 |
| lithium lengthens circadian period in a diurnal primate, saimiri sciureus. | lithium lengthens the period of free-running circadian rhythms in a variety of species, but this effect has not been demonstrated unequivocally in primates. because of the possible link between lithium's action on the circadian clock and its therapeutic action in human mood disorders, we tested the ability of lithium to lengthen circadian period in a diurnal primate with circadian properties similar to those of humans. lithium carbonate was administered in food pellets to 8 adult male squirrel m ... | 1990 | 2116188 |
| the compartmentalization of the monkey and rat cerebellar cortex: zebrin i and cytochrome oxidase. | the cerebellar cortex of mammals is composed of parasagittal zones that encompass the afferent inputs, the efferent corticonuclear and corticovestibular projections, and a number of intrinsic molecular markers. one such marker is the polypeptide antigen zebrin i that is recognized by monoclonal antibody (mab) q113. in rodents, zebrin i immunocytochemistry reveals an array of parasagittal purkinje cell compartments. in the present study, zebrin i has been used to reveal the molecular heterogeneit ... | 1990 | 2154279 |
| reactivation of hsv-1 in primates by transcorneal iontophoresis of adrenergic agents. | transcorneal iontophoresis of adrenergic agents has been shown to reactivate latent herpes simplex virus type 1 (hsv-1) and to produce viral shedding in the tear film in rabbits and mice, but not, to date, in nonhuman primates. in this study, we demonstrated induced reactivation of latent hsv-1, viral shedding, and production of ocular lesions in nine squirrel monkeys (saimiri sciureus) by iontophoresis of 6-hydroxydopamine (6-hd) with topical instillation of epinephrine or with iontophoresis of ... | 1990 | 2156785 |
| vitamin c deficiency in captive nonhuman primates fed commercial primate diet. | scurvy was diagnosed in 19 rhesus monkeys (macaca mulatta) and four squirrel monkeys (saimiri sciureus) from a colony of nonhuman primates maintained on a commercial diet. signs of weakness, reluctance to move, gingival hemorrhage, bruising, proximal and distal metaphyseal fractures, weight loss and anemia appeared in juvenile and young adult rhesus monkeys over a 2 week period. clinical signs subsided after 5 days of vitamin c therapy. at the same time, cephalohematomas and weakness developed i ... | 1990 | 2157096 |
| anatomical distribution of developing trophozoites and schizonts of plasmodium vivax in aotus lemurinus lemurinus and saimiri sciureus. | organ distribution of developing trophozoite- and schizont-infected erythrocytes of plasmodium vivax and night monkeys, aotus lemurinus lemurinus, and squirrel monkeys, saimiri sciureus, was determined. the primary site for the infection in both species was the splenic vasculature. secondary organ involvement differed between hosts although some overlapping did occur. | 1990 | 2191104 |
| immunohistochemical study of the serotoninergic innervation of the basal ganglia in the squirrel monkey. | a specific antibody raised against 5-hydroxytryptamine (5-ht) conjugated to bovine serum albumin was used to study the serotoninergic innervation of the basal ganglia in the squirrel monkey (saimiri sciureus). at midbrain level, numerous fine 5-ht-immunoreactive axons were seen to arise from the immunopositive neurons of the dorsal raphe nucleus and less abundantly from those of the nucleus centralis superior. the bulk of these axons formed a rather loosely arranged bundle that arched ventrorost ... | 1990 | 2212111 |
| the peruvian iii strain of plasmodium brasilianum in saimiri sciureus boliviensis monkeys. | a strain of plasmodium brasilianum was isolated from a naturally infected saimiri monkey from peru and subsequently passaged to 21 splenectomized saimiri sciureus boliviensis monkeys. nine of 12 attempts to transmit infection by sporozoite inoculation were successful with prepatent periods ranging from 23 to 41 days. gametocytes were infective to anopheles freeborni, anopheles stephensi, anopheles dirus, anopheles maculatus, and anopheles gambiae mosquitoes. the strain demonstrated a high level ... | 1990 | 2213410 |
| transmission of plasmodium fragile to saimiri monkeys. | saimiri monkeys from bolivia and guyana were infected with the nilgiri and ceylon strains of plasmodium fragile. of 20 attempted sporozoite transmissions of the ceylon strain involving 11 splenectomized saimiri sciureus boliviensis, only 8 were successful, 2 by mosquito bite and 6 by intravenous injection of sporozoites dissected from salivary glands. prepatent periods ranged from 18 to 30 days with a mean of 25.8 days. | 1990 | 2213417 |
| number-related discrimination and summation by squirrel monkeys (saimiri sciureus sciureus and s. boliviensus boliviensus) on the basis of the number of sides of polygons. | in experiment 1, with the number of sides or angles of irregular polygons as cues, programmed training, and a 90% correct criterion (36 of 40), 2 squirrel monkeys' (saimiri sciureus sciureus and s. boliviensus boliviensus) best performances were to discriminate heptagons from octagons, a 3rd's best was hexagons from heptagons, and a 4th's best was pentagons from heptagons. in experiment 2, on most trials 2 polygons on one or both discriminanda had to be summed to determine which discrimination h ... | 1990 | 2225761 |
| light suppression of melatonin in the squirrel monkey (saimiri sciureus). | this study examined plasma melatonin levels and the suppressant effect of light on melatonin production in the squirrel monkey. monkeys were maintained on a 12:12 light-dark cycle (ld 12:12) with lights on from 07:00 to 19:00. plasma levels of melatonin were determined by gas chromatography negative chemical ionization mass spectrometry. melatonin levels at 00:00 (99.5 +/- 18.9 pg/ml) were significantly higher than at 02:00 (57.21 +/- 7.7 pg/ml; student's t = 2.859; p less than or equal to 0.021 ... | 1990 | 2231270 |
| amyloid in the brains of aged squirrel monkeys. | in this immunocytochemical study, the brains of nine squirrel monkeys (saimiri sciureus), ranging from 8 to 27 years of age, were examined for the presence and distribution of beta/a4 amyloid, a 4-kilodalton peptide. in aged squirrel monkeys, amyloid is associated primarily with intracerebral and meningeal capillaries and arterioles and occurs to a lesser degree as small and/or diffuse deposits in the neural parenchyma and in the dense cores of senile plaques. cerebrovascular amyloid is found pr ... | 1990 | 2239150 |
| functional characterization of the antibody-mediated protection against blood stages of plasmodium falciparum in the monkey saimiri sciureus. | the squirrel monkey saimiri sciureus is one of the world health organization recommended experimental models of plasmodium falciparum blood stage infection. anti-malaria antibodies developed by this host after a drug-controlled infection play an important part in the acquired protection against the p. falciparum blood stages. furthermore, the use of two anti-saimiri immunoglobulin (ig) monoclonal antibodies (mab) has permitted the differentiation between protective (mab 3a2/g6) and non-protectiv ... | 1990 | 2242760 |
| morphologic development of the adrenal cortex in squirrel monkeys (saimiri sciureus). | this study describes the morphology of the squirrel monkey (saimiri sciureus) adrenal gland in the perinatal period. adrenals of fetal monkeys had a broad central zone of large eosinophilic cells (fetal zone) surrounded by a subcapsular band of small dark cells (definitive zone). adrenals of stillborn and neonatal monkeys had a reduced fetal zone and an expanded definitive zone that was differentiated into distinct zona fasciculata and zona glomerulosa. by day 18 postpartum, no remnant of the fe ... | 1990 | 2254916 |
| plasma carotenoids of monkeys (macaca fascicularis and saimiri sciureus) fed a nonpurified diet. | the major carotenoid pigments in the plasma and in a common, nonpurified diet of two species of monkeys (macaca fascicularis and saimiri sciureus) were measured. the xanthophylls, lutein, zeaxanthin, alpha-cryptoxanthin, and beta-cryptoxanthin, were the principal carotenoids in both the diet and the plasma. lutein and zeaxanthin were abundant in the all-trans, the 9-cis, and the 13-cis geometrical isomers in the diet, but the 9-cis form was rarely measurable in plasma. however, the 13-cis isomer ... | 1990 | 2262812 |
| a rhoptry antigen of plasmodium falciparum is protective in saimiri monkeys. | a non-polymorphic antigen associated with the rhoptry organelles of plasmodium falciparum has been purified by immunoaffinity chromatography. the antigen, rap-1 (rhoptry associated protein-1), which is defined by monoclonal antibodies which inhibit parasite growth in vitro, is a multi-component antigen consisting of four major proteins of 80, 65, 42 and 40 kda and two minor proteins of 77 and 70 kda. these proteins were electro-eluted from preparative sodium dodecyl sulphate polyacrylamide gels ... | 1990 | 2263413 |
| [management of individual body weight growth of infant squirrel monkey (saimiri sciureus) in indoor breeding colony]. | we biometrically analyzed the body weight growth data of new-born squirrel monkeys, obtained during the nursing period from 0 to 12 weeks of age. body weight (y in grams) could be expressed as a function of birth weight (a in grams) and age (x in weeks) by the following equation: y = a + b x, where b indicates growth rate. this equation corresponded significantly with actual growth curves (r2 = 0.96). the frequency distribution of b values was demonstrated to be abnormal distribution. this value ... | 1990 | 2303094 |
| processing of amplitude modulated sounds in the medial geniculate body of squirrel monkeys. | the responses of single and multi units in the medial geniculate body of the squirrel monkey (saimiri sciureus) to modulation frequency, modulation depth and changes in absolute intensity of sinusoidally amplitude modulated (am) sounds were studied. both spike-frequency and spike rate modulation were used as a measure for neuronal response. spike rate modulation was derived from fft (fast-fourier-transformation) analysis of the psths. in all cases (n = 133) spike rate modulation was shown to be ... | 1990 | 2311698 |
| partial humeri of two miocene colombian primates. | distal portions of humeri from two miocene colombian primates were recovered during field work in 1986. the larger igm 183420 is very similar in size and morphology to the humerus included in the type specimen of cebupithecia sarmientoi, recovered from la venta in 1945 (stirton and savage: serv. geol. nac. bogata 7:345-356, 1951) and is assigned to this taxon. igm 183420 presents a number of features of the humerus associated with clinging postural behaviors in living platyrrhines, including a m ... | 1990 | 2327481 |
| efferent projections of the subthalamic nucleus in the squirrel monkey as studied by the pha-l anterograde tracing method. | the organization of the efferent connections of the subthalamic nucleus was studied in the squirrel monkey (saimiri sciureus) by using the lectin phaseolus vulgaris-leucoagglutinin (pha-l) as an anterograde tracer. at the level of the basal forebrain, anterogradely labeled fibers and axon terminals were mostly found in the striatopallidal complex and the substantia innominata. in cases in which the pha-l injection sites were placed in the central or the lateral third of the subthalamic nucleus, ... | 1990 | 2332533 |
| subcutaneous leiomyosarcoma in a peruvian squirrel monkey (saimiri sciureus). | 1990 | 2345936 | |
| reduced nicotinamide adenine dinucleotide phosphate-diaphorase (nadph-d) histochemistry in the hippocampal formation of the new world monkey (saimiri sciureus). | nicotinamide adenine dinucleotide phosphate-diaphorase (nadph-d) containing fibers and neurons within the hippocampal formation and entorhinal cortex of the new world monkey were determined using a direct histochemical procedure. occasional intensely stained bipolar nadph-d positive neurons were seen in the polymorphic zone within the hilus of the dentate gyrus and molecular layer of the hippocampus. although virtually no intensely stained cells were seen in the ca subfields, a few small oval li ... | 1990 | 2364290 |
| distribution of chromosomal polymorphisms in three subspecies of squirrel monkeys (genus saimiri). | the presence of nucleolar organizer regions (nors) and c-band polymorphisms has been examined in three subspecies of squirrel monkeys, saimiri sciureus sciureus, s. boliviensis boliviensis, and s. boliviensis peruviensis. pericentric inversions in chromosomes 15 and 16 were also examined in the three groups. chromosome 15 was acrocentric in s. s. sciureus and submetacentric in s.b. boliviensis and s.b. peruviensis. chromosome 16 was acrocentric in s.s. sciureus and s.b. boliviensis while being s ... | 1990 | 2369837 |
| retinal vasculature of the fovea of the squirrel monkey, saimiri sciureus: three-dimensional architecture, visual screening, and relationships to the neuronal layers. | the retinal vasculature of the fovea of squirrel monkeys was studied in retinal whole mounts and in sections of the same retinas. at the center of the fovea there is an approximately circular avascular zone surrounded by a set of terminal capillaries in the inner nuclear layer. within the foveal depression, four capillary planes that bear a precise relationship to the neuronal organization appear in a specific sequence with increasing eccentricity. the first plane to be established is the domina ... | 1990 | 2376631 |
| leishmania braziliensis in the squirrel monkey: development of primary and satellite lesions and lack of cross-immunity with leishmania donovani. | three female and 2 male adult laboratory-reared squirrel monkeys (saimiri sciureus) that previously had been inoculated with leishmania (leishmania) donovani and had recovered from experimental visceral leishmaniasis were each inoculated intradermally at the dorsal base of the tail with 2.2 x 10(7) culture-derived promastigotes of leishmania (viannia) panamensis. the progression and regression of subsequent lesions were examined for 36 wk in all 5 monkeys after which 3 of the monkeys were killed ... | 1990 | 2380874 |
| compensation of vertical vestibulo-ocular functions in squirrel monkeys after unilateral labyrinthectomy. | modifications in the vertical vestibulo-ocular reflex (vvor) were studied in four squirrel monkeys (saimiri sciureus) over time after unilateral labyrinthectomy. in the dark, with head upright, animals were exposed to sinusoidal rotation in the pitch plane. the magnetic field-pericorneal search coli technique was used to detect eye movement. the upward and downward slow-phase eye velocity (spev) of the vvor and the maximum spev of the vertical component of spontaneous nystagmus (spn) were studie ... | 1990 | 2382784 |
| a comparative study of neonatal skeletal development in cebus and other primates. | comparisons of hand/wrist radiographs of neonatal cebus albifrons (n = 14) and cebus apella (n = 4) with those of saimiri sciureus boliviensis (n = 9) and macaca mulatta (n = 63) reveal that the cebid monkeys show much less skeletal ossification at birth than macaques. differences in gestation time alone cannot account for the differences in skeletal maturity at birth in the two groups of monkeys. the skeletal precocity of the newborn macaques indicates that their ossification either begins earl ... | 1990 | 2391051 |
| dietary restriction and aging: the initiation of a primate study. | juvenile (1 yr) and adult (3-5 yr) male rhesus monkeys (macaca mulatta) and juvenile (1-4 yr) and adult (5-10 yr) male squirrel monkeys (saimiri sciureus) were fed a diet at or near ad libitum levels based on recommended caloric intake for age and body weight or fed 30% less of the same diet with this restriction gradually introduced over a 3-mo period. analysis of body weights among these respective control and experimental groups from the first year of the study indicated that the monkeys unde ... | 1990 | 2394908 |
| behavioral and physiological responses to maternal separation in squirrel monkeys (saimiri sciureus). | this study extends an examination of the behavioral and pituitary-adrenal responses of infant squirrel monkeys (saimiri sciureus) separated from their mothers under different environmental conditions to another physiological system by measuring the metabolites of the central monoamines found in the cerebrospinal fluid (csf). this study included spectrographic examination of the vocalizations emitted by the infant during separation. infants were separated from their mothers for 24 hr under 3 cond ... | 1990 | 1690548 |
| the centre médian and parafascicular thalamic nuclei project respectively to the sensorimotor and associative-limbic striatal territories in the squirrel monkey. | the striatal projections of the centre médian (cm) and parafascicular (pf) thalamic nuclei were examined in the squirrel monkey (saimiri sciureus) by using the lectin wheat germ agglutinin conjugated to horseradish peroxidase (wga-hrp) as an anterograde tracer. cm was found to project massively to the putamen, where terminal fields appeared principally in the form of oblique bands, and more diffusely to the dorsolateral border of the caudate nucleus. striatal inputs from pf were found more rostr ... | 1990 | 1691043 |
| compartmental origins of the striatopallidal projection in the primate. | the organization of striatopallidal projection neurons in the primate was studied by injecting horseradish peroxidase conjugated with wheat germ agglutinin and fluorescent markers (latex microspheres, fluorogold, diamidino yellow or nuclear yellow) into the globus pallidus of 20 adult squirrel monkeys (saimiri sciureus). single injections of horseradish peroxidase conjugated with wheat germ agglutinin were placed so as to involve predominantly either one or both pallidal segments. in the double- ... | 1990 | 1691462 |
| further studies on the immunization of saimiri sciureus boliviensis with recombinant vaccines based on the circumsporozoite protein of plasmodium vivax. | reported are the results of a trial in squirrel monkeys of 2 plasmodium vivax malaria vaccine candidates based on the circumsporozoite (cs) protein, namely, rpvcs-2 and rpvcs-3. compared with an earlier recombinant p. vivax cs construct, rpvcs-1, rpvcs-2 has an additional 24 amino acids at the c-terminal, which includes the thrombospondin region of homology and a putative t cell epitope. the rpvcs-3 was generated from a chemically synthesized gene that contained an additional 54 amino acids at t ... | 1990 | 1702586 |
| the monoaminergic innervation of the amygdala in the squirrel monkey: an immunohistochemical study. | the monoaminergic innervation of the amygdala of the squirrel monkey (saimiri sciureus) was studied by using immunohistochemical methods with primary antisera raised against serotonin, and the catecholamine synthesizing enzymes tyrosine hydroxylase, dopamine-beta-hydroxylase and phenylethanolamine-n-methyltransferase. serotonin was widely distributed within the amygdala including profuse terminal labeling in central, basolateral and cortical nuclear groups. the accessory basal and medial nuclei ... | 1990 | 1977101 |
| effects of mixed-species association on resource use by saimiri sciureus and cebus apella. | short-term associations between primate species offer the opportunity to measure changes in individual behavior and ecology in response to alterations in group size and composition. during a three-month study of associations between squirrel monkeys (saimiri sciureus) and brown capuchin monkeys (cebus apella) in manu national park, peru, i measured resource use and feeding efficiency for both species when in mixed and solitary troops, as well as the context and outcome of competitive interaction ... | 1990 | 31963980 |
| genetic relationships among three squirrel monkey types: implications for taxonomy, biomedical research, and captive breeding. | fourteen electrophoretically variable and 12 monomorphic erythrocytic and serum proteins were used to determine the genetic relationships among bolivian squirrel monkeys (saimiri boliviensis boliviensis), peruvian squirrel monkeys (saimiri boliviensis peruviensis), and guyanese squirrel monkeys (saimiri sciureus sciureus). the results supported the classification scheme of hershkovitz (american journal of primatology 7:155-210, 1984), which is used above. a profile of marker phenotypes can unamb ... | 1990 | 31963960 |
| immunological response and ovarian histology of squirrel monkeys (saimiri sciureus) immunized with porcine zona pellucida zp3 (mr = 55,000) macromolecules. | zp3 (m, = 55,000) is the major electrophoretic component of the porcine zona pellucida (zp). in a continuing assessment of zp3 as a candidate antigen for contraceptive vaccine development, female squirrel monkeys were immunized with 200 μg zp3 using either freund's adjuvant (fa) or muramyl dipeptide (mdp) and the effect of such immunization on ovarian histology examined. two experimental and three control groups were immunized: group 1 (n = 4), zp3 plus fa; group 2 (n = 4),zp3 plus mdp; and cont ... | 1991 | 31952394 |
| 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 |
| biological control of primate macular pigment. biochemical and densitometric studies. | the amounts of zeaxanthin (z) and lutein (l), the carotenoids constituting the primate macular pigment, were measured in the central retinas of monkeys (saimiri sciureus and macaca fascicularis). two independent methods--reverse-phase high-performance liquid chromatography (hplc) and microdensitometry--were used for analysis of the same set of retinas. most of the measurements were made on retinas that had been fixed by glutaraldehyde-paraformaldehyde perfusion of the animal. control experiments ... | 1991 | 1993576 |
| distribution of individual macular pigment carotenoids in central retina of macaque and squirrel monkeys. | the spatial distribution of lutein (l) and zeaxanthin (z), the structural isomers composing the macular pigment, was studied in the retinas of macaque monkeys (macaca fascicularis) and squirrel monkeys (saimiri sciureus). spatial profiles of macular pigment optical density were obtained from retinal whole mounts. then concentric annuli were microdissected from the fovea and adjacent regions of the same retinas. each retinal segment was analyzed for carotenoids by high-performance liquid chromato ... | 1991 | 1993577 |
| renal response to 7 days of lower body positive pressure in squirrel monkeys. | the purpose of this study was to characterize the renal response to central volume expansion using lower body positive pressure (lbpp) in the adult male squirrel monkey (saimiri sciureus). urinary excretion of sodium, potassium, and water and plasma aldosterone concentrations were measured during a control day, 7 days of lbpp, and a recovery day. time control experiments in the same animals included chair sitting without exposure to lbpp. seven monkeys (600-1,000 g) were trained to sit in a spec ... | 1991 | 2012244 |
| [yersinia pseudotuberculosis in new world monkeys]. | it is reported on four cases of pseudotuberculosis in 2 saimiri sciureus, 1 callithrix jacchus/penicillata hybrid and 1 s. oedipus. the animals came from two different groups, one being infected with y. pseudotuberculosis serotype i, the other with y. pseudotuberculosis serotype ii. all cases showed intestinal infection of thermophile campylobacter. remarkable were severe haemorrhagic components and the distinct rhs-proliferation, especially in the mesenteric lymphatic nodes. | 1991 | 2015031 |
| immune modulation of prevotella intermedia colonization in squirrel monkeys. | colonization of the gingival crevice by black-pigmented porphyromonas or prevotella spp. (bp/p), including porphyromonas gingivalis (formerly bacteroides gingivalis) and prevotella intermedia (formerly bacteroides intermedius), is thought to be an important ecological event which may result in the destruction of connective tissues supporting the teeth. theoretically, periodontal diseases could be prevented if these or other periodontal pathogenic microorganisms did not colonize the subgingival a ... | 1991 | 2037354 |
| renal pathology in saimiri monkeys during a vaccine trial using the recombinant circumsporozoite protein of plasmodium vivax. | renal specimens of squirrel monkeys (saimiri sciureus boliviensis) were studied by light microscopy and immunohistochemistry to examine the pathologic changes during vaccine trials with four recombinant circumsporozoite (cs) proteins (rpvcs-1, rpvcs-2, rpvcs-3, ns1(81) v20) of plasmodium vivax. the monkeys were vaccinated and later challenged with p. vivax sporozoites. among the 33 posttrial biopsies, 17 had mild to moderate mesangial proliferation and nine had interstitial nephritis. immunohist ... | 1991 | 2042706 |
| delta activity from amygdala in squirrel monkeys (saimiri sciureus): influence of social and environmental context. | a previous study reported that power in the delta band of the amygdala is selectively elevated when primates are exposed to affectively ladened stimuli (kling, steklis, & deutsch, 1979). radiotelemetric recordings suggested that this elevation was greatest when the animal was confronted with conspecific behaviors that could be interpreted as "ambiguous." in the present study, a specific elevation of delta activity was observed when the animal was placed in an environment in which uncued shock ha ... | 1991 | 2043270 |
| breeding readiness in squirrel monkeys: female-primed females are triggered by males. | the south american squirrel monkey (saimiri) shows pronounced annual variations in reproductive activity. we investigated the contribution of social stimulation to breeding readiness, as reflected in behavior and gonadal hormones. a previous study indicated that formation of new heterosexual pairs can induce breeding readiness in males, but not in females. in the present study we examined the response of individually housed females to the formation of triads of unacquainted females and, subseque ... | 1991 | 2062922 |
| experimental american leishmaniasis and chagas' disease in the brazilian squirrel monkey: effect of dual infection on antibodies to parasite antigens. | adult, laboratory-bred squirrel monkeys (saimiri sciureus) were infected with either leishmania braziliensis braziliensis or l. b. panamensis and, 42 weeks later, they were challenge-infected with trypanosoma cruzi. another group of monkeys was infected with t. cruzi and challenged with l. b. braziliensis after 42 weeks. immunoblotting was used to examine parasite antigens bound by antibodies in plasma obtained from the monkeys during the course of primary and challenge infections. during primar ... | 1991 | 1743848 |
| serotoninergic innervation of the thalamus in the primate: an immunohistochemical study. | little is known of the serotoninergic innervation of the thalamus in primates; therefore, we undertook a detailed study of the distribution of 5-hydroxytryptamine (5-ht)-immunoreactive neuronal profiles in the thalamus of the squirrel monkey (saimiri sciureus) with a specific antibody directly raised against 5-ht. all thalamic nuclei in the squirrel monkey displayed 5-ht-immunoreactive fibers, but none contained immunopositive cell bodies. the 5-ht innervation of the thalamus derived from extrin ... | 1991 | 1744240 |
| the mossy cells of the fascia dentata: a comparative study of their fine structure and synaptic connections in rodents and primates. | in this study the fine structure and synaptic connections of mossy cells in the rat and monkey fascia dentata were analyzed. in order to study commissural connections of identified mossy cells in the rat, hilar neurons were retrogradely labeled by horseradish peroxidase (hrp) or fast blue (fb) injections into the contralateral hippocampus. vibratome sections containing retrogradely hrp-labeled hilar neurons were golgi-impregnated and gold-toned. hilar commissural neurons identified by contralate ... | 1991 | 1744242 |
| osmotic fragility of erythrocytes in bolivian and brazilian squirrel monkeys (saimiri sciureus). | median corpuscular fragility of erythrocytes does not differ significantly between fed and fasted bolivian and brazilian squirrel monkeys and are similar to values reported in humans and rhesus monkeys. this report further confirms that the fasting hyperbilirubinemia present only in bolivian squirrel monkeys with a gilbert-like syndrome is not due to an increased fragility of erythrocytes and should be classified as a nonhemolytic hyperbilirubinemia. | 1991 | 1757975 |
| microvascular architecture of the palatine mucosa in the common squirrel monkey (saimiri sciureus). | detailed observations were made of the structure and microvasculature of the palatine mucous membrane of the common squirrel monkey (saimiri sciureus) by means of the plastic injection method under a scanning electron microscope. the findings obtained were compared with those of the japanese monkey and other mammals. the osseous palate was flat horizontally and a pair of incisive foramina were apparently open at the anterior end of the hard palate. at the posterior end of the osseous palate, the ... | 1991 | 1758683 |
| distribution of cholinergic pallidal neurons in the squirrel monkey (saimiri sciureus) based upon choline acetyltransferase. | the distribution of cells immunoreactive to choline acetyltransferase (chat-ir) in, and around the globus pallidus were studied in the squirrel monkey. intrinsic pallidal chat-ir neurons in the globus pallidus were most numerous in ventrocaudal regions of the lateral pallidal segment (lps) and in the oral pole of the medial pallidal segment (mps). smaller numbers of chat-positive cells were seen in portions of the medullary laminae of the pallidum. computer measurements of somal areas of chat-ir ... | 1991 | 1779134 |
| behavioral development and maternal care in tufted capuchins (cebus apella) and squirrel monkeys (saimiri sciureus) from birth through seven months. | fourteen infant capuchins and eight squirrel monkeys reared by their mothers in captive species-typical social groups were observed from birth through 7 months. motoric altriciality of the neonatal capuchin relative to the squirrel monkey is a key feature of behavioral differences between the species in the first few months after birth. infants of the two species differed substantially in age at onset of independent locomotion, the developmental profile of independent activities, and the overall ... | 1991 | 1783220 |
| peripheral blood mononuclear cells in the squirrel monkey saimiri sciureus. ii. exploration of the il2/il2r pathway of t-cell activation. | we report here on functional aspects of squirrel monkey t cells isolated either from peripheral blood mononuclear cells or in the presence of accessory cells or accessory-cell-secreted cytokines. the t-cell response triggered by polyclonal activators was measured through proliferation, t-cell growth factor production and transient expression of receptors to growth factors. we also sought to delineate mechanisms by which antimitogenic molecules might prevent lymphocytes from being able to express ... | 1991 | 1796209 |
| contralateral pallidothalamic and pallidotegmental projections in primates: an anterograde and retrograde labeling study. | unilateral injections of the anterograde tracer phaseolus vulgaris-leucoagglutinin (pha-l) in the internal segment of the pallidum (gpi) of the squirrel monkey (saimiri sciureus) led to anterograde labeling of fibers ipsilaterally in the following thalamic nuclei: ventral anterior (va), ventral lateral (vl), centromedian (cm), and lateral habenula (hbl). the labeled fibers reached these ipsilateral thalamic nuclei by coursing along or through the ansa lenticularis, the lenticular and thalamic fa ... | 1991 | 1817727 |
| the benzodiazepine triazolam phase-shifts circadian activity rhythms in a diurnal primate, the squirrel monkey (saimiri sciureus). | triazolam can shift the phase of circadian rhythms in hamsters recorded in constant light or dark. this effect is apparently mediated by physical activity stimulated by the drug. we examined whether triazolam can shift the phase of circadian rhythms in a diurnal primate, the squirrel monkey, that is sedated by triazolam. single injections of triazolam at 0.15-0.20 mg/kg induced phase advances or delays of monkey activity rhythms recorded in constant light. the phase-response curve is similar to ... | 1991 | 1857540 |
| vocalization-correlated single-unit activity in the brain stem of the squirrel monkey. | the brain stems of 17 squirrel monkeys (saimiri sciureus) were systematically explored for vocalization-related single-unit activity during calls electrically elicited from the periaqueductal grey. of 12,280 cells tested, 1151 fired in relation to vocalization. of these, 587 reacted to external acoustic stimuli and started firing after vocalization onset. as most of these cells were located in classical auditory relay structures, they probably represent auditory neurones reacting indirectly to s ... | 1991 | 1864326 |
| anatomic evidence of nociceptive inputs to primary somatosensory cortex: relationship between spinothalamic terminals and thalamocortical cells in squirrel monkeys. | this study examined anatomic pathways that are likely to transmit noxious and thermal cutaneous information to the primary somatosensory cortex. anterograde and retrograde labeling techniques were combined to investigate the relationship between spinothalamic (stt) projections and thalamocortical neurons in the squirrel monkey (saimiri sciureus). large injections of diamidino yellow (dy) were placed in the physiologically defined hand region of primary somatosensory cortex (hsi), and wheat germ ... | 1991 | 1865012 |
| ultrastructure of erythrocytes from aotus trivirgatus and saimiri sciureus monkeys infected by plasmodium vivax. | erythrocytes from aotus and saimiri monkeys parasitized by plasmodium vivax show dramatic changes starting during the early stages of parasite development. invaginations of the erythrocyte membrane, caveolae, are found during all parasite development stages. up to six vesicles can be fused with one caveola, forming a caveola-vesicle complex. as the parasite grows, large accumulations of these vesicles can be seen within the erythrocyte cytoplasm. in addition to these caveolae-vesicle complexes, ... | 1991 | 1891448 |
| subgingival microbiota in squirrel monkeys with naturally occurring periodontal diseases. | the squirrel monkey (saimiri sciureus) has been proposed as an in vivo model for the study of subgingival colonization by suspected periodontopathogens, such as black-pigmented porphyromonads and prevotellas (bp/p). however, the indigenous microbiota of the squirrel monkey has not been well described. therefore, in order to more fully characterize the oral microbiota of these animals, we studied two groups of squirrel monkeys from widely different sources. group i consisted of 50 breeding colony ... | 1991 | 1937762 |
| intensity-amplitude relationships in monkey event-related potentials: parallels to human augmenting-reducing responses. | in human, the amplitudes of specific event-related potential (erp) components can increase or decrease in response to increasing stimulus intensity depending on the location of the recording site. large increases characterize components presumably generated by modality-specific sites, while smaller increases or even decreases are associated with those originating in associational areas. comparable data from non-human primates, which would permit invasive studies of the neural substrates underlyi ... | 1991 | 1712281 |
| projection from the external pallidum to the reticular thalamic nucleus in the squirrel monkey. | small injections of biocytin in the external segment of the pallidum (gpe) of the squirrel monkey (saimiri sciureus) led to anterograde labeling of fibers in the thalamic reticular nucleus (nrt). these fibers reached nrt by coursing along the ventral tip of the internal capsule or by directly piercing the internal capsule more dorsally. they arborized profusely within the entire rostrocaudal extent of the nucleus. within nrt, biocytin-labeled fibers were long, slightly varicosed, and emitted num ... | 1991 | 1716174 |
| thalamically projecting cells of the lateral cervical nucleus in monkey. | the number, location, and morphology of thalamically projecting lateral cervical nucleus (lcn) cells were determined in monkey using retrograde transport of wheatgerm agglutinin-conjugated horseradish peroxidase. these data were compared to the total population of lcn neurons as determined by nissl stain. in 4 macaca fascicularis and one saimiri sciureus the average size of the thalamic projection from lcn was found to be 506 +/- 94 cells contralateral to the injections. thalamically projecting ... | 1991 | 1718552 |
| corticostriatal transformations in the primate somatosensory system. projections from physiologically mapped body-part representations. | 1. the basal ganglia of primates receive somatosensory input carried largely by corticostriatal fibers. to determine whether map-transformations occur in this corticostriatal system, we investigated how electrophysiologically defined regions of the primary somatosensory cortex (si) project to the striatum in the squirrel monkey (saimiri sciureus). receptive fields in the hand, mouth, and foot representations of cortical areas 3a, 3b, and 1 were mapped by multiunit recording; and small volumes of ... | 1991 | 1722244 |
| epstein-barr virus transformation of saimiri sciureus (squirrel monkey) b cells and generation of a plasmodium brasilianum-specific monoclonal antibody in p. brasilianum-infected monkeys. | the new-world monkeys saimiri sciureus (squirrel monkeys) are currently used as a model to test the efficacy of vaccines against human malaria. to improve our knowledge on this model, we tested the susceptibility of s. sciureus b cells to epstein-barr virus (ebv) infection. b-lymphoblastoid cell lines were obtained from six of six healthy animals after infection with the b95-8 source of ebv. the frequency distributions of spleen b cells clonally committed to the production of immunoglobulins m a ... | 1991 | 1646769 |
| evidence of an x zone in lobule v of the squirrel monkey (saimiri sciureus) cerebellum: the distribution of corticonuclear fibers. | the distribution of corticonuclear fibers to medial-most parts of the posterior interposed nucleus (nip) from lateral areas of the vermis was studied in the squirrel monkey (saimiri sciureus), using a silver impregnation method. the origin and course of degenerated fibers were studied in serial sections. the distribution pattern of corticonuclear fibers from a series of small well localized lesions placed in the vermis and paravermal cortex of lobule v is compatible with the interpretation that ... | 1991 | 1665319 |
| plasmodium falciparum: genetic stability of the uganda palo alto strain propagated in the squirrel monkey (saimiri sciureus). | the uganda palo alto strain of plasmodium falciparum has been extensively used in several laboratories to infect saimiri monkeys. in the study reported here three distinct lines derived by parallel serial blood transfers from a single 10-year-old passage of the palo alto strain were examined for genetic diversity using the polymerase chain reaction and restriction mapping techniques. a comparison of the pf 11.1, p190, msa2, s-ag, and kahrp genes indicates that these parasite lines are apparently ... | 1991 | 1673101 |