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Showing papers on "Primate published in 1993"


Journal ArticleDOI
TL;DR: It is demonstrated that attended natural stimulation can modify the tonotopic organization of Al in the adult primate, and that this alteration is correlated with changes in perceptual acuity.
Abstract: Previous studies have shown that the tonotopic organization of primary auditory cortex is altered subsequent to restricted cochlear lesions (Robertson and Irvine, 1989) and that the topographic reorganization of the primary somatosensory cortex is correlated with changes in the perceptual acuity of the animal (Recanzone et al., 1992a-d). Here we report an increase in the cortical area of representation of a restricted frequency range in primary auditory cortex of adult owl monkeys that is correlated with the animal's performance at a frequency discrimination task. Monkeys trained for several weeks to discriminate small differences in the frequency of sequentially presented tonal stimuli revealed a progressive improvement in performance with training. At the end of the training period, the tonotopic organization of Al was defined by recording multiple-unit responses at 70-258 cortical locations. These responses were compared to those derived from three normal monkeys and from two monkeys that received the same auditory stimuli but that were engaged in a tactile discrimination task. The cortical representation, the sharpness of tuning, and the latency of the response were greater for the behaviorally relevant frequencies of trained monkeys when compared to the same frequencies of control monkeys. The cortical area of representation was the only studied parameter that was correlated with behavioral performance. These results demonstrate that attended natural stimulation can modify the tonotopic organization of Al in the adult primate, and that this alteration is correlated with changes in perceptual acuity.

1,276 citations


Journal ArticleDOI
TL;DR: Early data indicate that DR can be safely instituted in adult monkeys, but that longer term and/or more severe DR is required to determine if it is capable of influencing age-sensitive indices in long-lived primates.
Abstract: Dietary restriction (DR) retards aging processes and extends maximum life span in rodents and in simpler animals. We initiated a study in 30 adults (8-14 years old) male rhesus monkeys to determine whether or not aging processes are retarded by adult-onset DR in a primate species and herein report results from the experiment's first year. Following a 3-6 month period when baseline data were obtained, 15 animals were assigned to a control group and given free access to a semipurified diet for 6-8 hours per day. The other 15 monkeys were fed the same diet but at 70% of their baseline intake levels predetermined individually. The animals are being evaluated semi-annually for body size and composition, physical activity, metabolic rate, glucose tolerance and insulin sensitivity, hematologic indices, immunologic function, and fingernail growth. Ocular function is assessed annually. The preliminary observations after one year are: (a) all monkeys appear to be in excellent health; (b) average body weights for controls increased by 9% while monkeys on DR did not gain weight; (c) monkeys on DR have less body fat than do control monkeys, whereas the amount of lean body mass has not been significantly influenced by DR; (d) there was a small but statistically significant reduction in physical activity for monkeys on DR relative to controls; and (e) DR has not overtly influenced the other measures. Control monkeys gradually reduced their voluntary levels of food intake during the first year of study, and food allotments to DR monkeys are being adjusted accordingly in order to reinstate the intended 30% difference between groups. These early data indicate that DR can be safely instituted in adult monkeys, but that longer term and/or more severe DR is required to determine if it is capable of influencing age-sensitive indices in long-lived primates.

223 citations


Journal ArticleDOI
TL;DR: The electrically stimulated macaque monkey's frontal eye field (FEF) region to localize and to analyze the smooth pursuit eye movement representation suggests that the FEF primarily conveys an eye acceleration signal to the pursuit system, and that this signal can be affected by visual retinal errors before effecting the smooth eye movements.
Abstract: 1. We electrically stimulated the macaque monkey's frontal eye field (FEF) region to localize and to analyze the smooth pursuit eye movement representation. Rhesus monkeys were trained to fixate st...

204 citations


Journal ArticleDOI
TL;DR: These findings suggest that in haplorhine primates the genetic systems controlling brain growth are linked to the systems governing the life cycle so that species with longer cycles have larger brains.
Abstract: In haplorhine primates (tarsiers, monkeys, apes, and humans), there is a significant correlation between brain weight and maximum life-span when the effect of body size is removed. There is also a significant correlation in haplorhine primates between brain weight and female age at first reproduction. For strepsirhine primates (lorises and lemurs), there are no significant correlations between brain weight and either life-span or female reproductive age when the effect of body size is removed. This lack of correlation in strepsirhine primates may be related to the fact that these primates are nocturnal and/or natives of the island of Madagascar, both of which conditions may reduce competition for resources and predation pressure. These findings suggest that in haplorhine primates the genetic systems controlling brain growth are linked to the systems governing the life cycle so that species with longer cycles have larger brains. When the effect of body weight is removed, leaf-eating haplorhines have significantly smaller brains and shorter lives than haplorhines with other diets. Harem-living haplorhines also have significantly smaller brains and shorter life-spans than troop-living haplorhines when the effect of body weight is removed. We also sought to test the rate-of-living hypothesis by determining whether primates with basal metabolic rates that are higher than would be expected for their body size have shorter maximum life-spans than would be expected for their body size. Metabolic rate is not correlated with life-span or female age at first reproduction when the effect of body size is removed.

180 citations


Journal ArticleDOI
TL;DR: Primates possess a sophisticated cognitive ability to interpret and respond to the social actions of conspecifics, and pathways which integrate such information converge in mesial temporal regions.

91 citations


Journal ArticleDOI
TL;DR: Although the magnitude of response of neurons in Alert infant IT cortex was lower overall, the incidence and features of stimulus selectivity shown by alert infant IT neurons were strikingly similar to those of IT cells of both anesthetization and unanesthetized adult monkeys.
Abstract: 1. Inferior temporal cortex (IT) is a "high-order" region of primate temporal visual cortex implicated in visual pattern perception and recognition. To gain some insight into the development of this area, we compared the properties of single neurons in IT in infant monkeys ranging from 5 wk to 7 mo of age with those of neurons in IT in adult animals. Both anesthetized and awake behaving paradigms were used. 2. In immobilized infant monkeys under nitrous oxide anesthesia, the incidence of visually responsive cells was markedly less than in adult monkeys studied under similar conditions. In infants 4-7 mo of age, only half of IT neurons studied were visually responsive, compared with > 80% in adult monkeys. In monkeys < 4 mo old, even fewer (< 10%) could be visually driven. "Habituation" of IT cells to repeated stimulus presentation appeared more pronounced in infant monkeys under nitrous oxide anesthesia than in adult animals. 3. IT cells in the anesthetized infant monkeys that did respond showed receptive field properties similar to those of responsive adult IT neurons studied under similar conditions. Two thirds of the receptive fields plotted in the anesthetized 4 to 7-mo-old group were bilateral, and median field size did not differ between the infants and comparable adult groups, being approximately 20 degrees on a side in each case. 4. In contrast to the results obtained under anesthesia, most IT cells in alert infant monkeys 5 wk-7 mo of age (80%) were responsive to visual stimuli, and this incidence of visually responsive IT neurons did not differ from that obtained in awake adult macaques. However, response magnitude, measured as spikes per second above baseline rate, was significantly lower in the infant alert sample than in the adult control (5.2 vs. 12.6 spikes/s, mean +/- SE, deviation from spontaneous rate, respectively). 5. In addition to having lower magnitudes of visual response, IT cells in the awake infants also tended to have longer and more variable latencies. The overall mean for the infant cells was 196 ms, compared with an overall mean of 140 ms for IT neurons in the alert control adult. 6. Although the magnitude of response of neurons in alert infant IT cortex was lower overall, the incidence and features of stimulus selectivity shown by alert infant IT neurons were strikingly similar to those of IT cells of both anesthetized and unanesthetized adult monkeys.(ABSTRACT TRUNCATED AT 400 WORDS)

86 citations


Journal ArticleDOI
TL;DR: Three kinds of evidence have been added to existing data sets in an effort to evaluate the adequacy of the single locus model, finding results in accord with the idea that some species of platyrrhine primate have only a single type of photopigment gene on the X-chromosome.

79 citations


Journal ArticleDOI
TL;DR: The data indicate that the evolutionary change in the expression of GAL‐ir within the primate basal forebrain occurs at the branch point of monkeys and apes.
Abstract: Galanin immunoreactivity (GAL-ir) is differentially expressed within the basal forebrain of monkeys and humans. Most monkey magnocellular basal forebrain neurons colocalize GAL-ir. In contrast, virtually no human magnocellular basal forebrain neurons express GAL-ir. Rather, an extrinsic galaninergic fiber plexus innervates these neurons in humans. The present study examined the expression of GAL-ir within the basal forebrain of apes to establish the phylogenetic level at which this transformation occurs. The staining patterns of GAL-ir within the basal forebrain of both lesser (gibbons) and great (chimpanzee and gorilla) apes were compared to that previously observed within monkeys and humans. All apes displayed a pattern of basal forebrain GAL-ir indistinguishable from humans. GAL-ir was not expressed within ape basal forebrain magnocellular neurons as seen in monkeys. Rather like humans, a dense collection of GAL-ir fibers was seen in close apposition to magnocellular perikarya. In addition, a few GAL-ir parvicellular neurons were scattered within the ape basal forebrain. These data indicate that the evolutionary change in the expression of GAL-ir within the primate basal forebrain occurs at the branch point of monkeys and apes.

67 citations


Journal ArticleDOI
TL;DR: Monkeys that spent their year of single-caging in indoor rooms showed higher activations of the hypothalamic-pituitary-adrenal system than did monkeys that spent theirs in outdoor buildings, suggesting that aspects of the environment outside of the cage (conspecific activity, environmental variation, etc.) may influence plasma cortisol.

45 citations


Journal ArticleDOI
TL;DR: The primate and rodent models developed in the present study will be useful for the study of the immunology and chemotherapy of onchocerciasis.
Abstract: Third-stage larvae (L3) of Onchocerca volvulus were implanted in diffusion chambers in chimpanzees, mangabey monkeys, rhesus monkeys, squirrel monkeys, and inbred strains of mice, jirds, and rats for 3-63 days. At different times during the experimental period, larvae were recovered and assessed for their viability and development. Survival and growth rates were equal regardless of whether the implanted larvae were fresh or cryopreserved. Survival and growth rates of the larvae did not differ among the primate and rodent hosts tested, with the exception of squirrel monkeys and rats, which were resistant to infection. Molting from L3 to fourth-stage larvae began on day 3 and continued through day 14 in the primates and rodents. The primate and rodent models developed in the present study will be useful for the study of the immunology and chemotherapy of onchocerciasis.

44 citations


Journal ArticleDOI
TL;DR: Consideration of the variable nature of the sequences at the multiple sites of proteolysis during the processing of the pro-P2 indicates either that there are several processing enzymes of differing specificities, or more likely that the folded structure of the Proteine P2 limits accessibility of a non-specific protease to certain exposed sites.
Abstract: Protamines P1 and P2 form a family of small basic peptides that represent the major sperm proteins in placental mammals. In human and mouse protamine P2 is one of the most abundant sperm proteins. The protamine P2 gene codes for a P2 precursor, pro-P2 which is later processed by proteolytic cleavages in its N-terminal region to form the mature P2 protamines. We have used polymerase chain amplification to directly sequence the pro-P2 genes of the five major primate families: red howler (Alouatta seniculus) is a New World monkey (Cebidae); the two macaque species, Macaca mulatta and M. nemistrina are Old World monkeys (Cercopithecidae), the gibbon, Hylobates lar, represents one branch of the apes (Hylobatidae); the orangutan, Pongo pygmaeus, gorilla, Gorilla gorilla and two species of chimpanzee Pan paniscus and Pan troglodytes represent a second ape family (Pongidae). These pro-P2 genes are compared with that of human [Domenjoud, L., Nussbaum, G., Adham, I. M., Greeske, G. & Engel, W. (1990) Genomics 8, 127-133]. The overall size and organization of the genes are conserved within the group. The mean length of pro-P2 is 101 residues, with an increase to 102 in M. nemistrina and a decrease to 99 residues in red howler (A. seniculus). In gorilla and red howler one of two 79-bp tandem repeats that occurs 3' of the gene is deleted. Of the 101 deduced amino acids examined, an amino acid change occurs in one or more primates at 45 positions. Considering only the most recently diverged group, the human/gorilla/chimpanzee clade, this represents a very high mutation rate of 0.99 changes/100 sites in 10(6) years. This rapid mutation rate is characteristic of both members of the protamine gene family, P1 and P2. Consideration of the variable nature of the sequences at the multiple sites of proteolysis during the processing of the pro-P2 indicates either that there are several processing enzymes of differing specificities, or more likely that the folded structure of the pro-P2 limits accessibility of a non-specific protease to certain exposed sites.

Journal Article
TL;DR: An epidemiologic study of shigellosis was the preliminary step in the formulation of a plan for the control of devastating infectious diseases in nonhuman primates at the National Zoological Park.
Abstract: An epidemiologic study of shigellosis was the preliminary step in the formulation of a plan for the control of devastating infectious diseases in nonhuman primates at the National Zoological Park. Data were collected from primate groups with enzootic shigellosis and included the following species: white-cheeked and siamong gibbons (Hylobates concolor and H syndactylies); lion-tailed, celebes, and Barbary macaques (Macaca silenus, M nigera, and M sylvanus); black and white colobus monkeys (Colobus guerzea); grey-cheeked mangabeys (Cerecocebus albigena); spider monkeys (Ateles susciceps robusuts); ruffed lemurs (Lemur varrigatus); lowland gorillas (Gorilla gorilla); and orangutans (pongo pygmaeus). Data included results of physical examination, proctoscopy with biopsy, fecal parasitologic and cytologic examinations, and bacteriologic culturing of swabbed specimens of rectum and gingiva. Repetitive fecal examinations were subsequently performed and included bacteriologic culturing of fecal specimens for enteropathogenic bacteria and parasites and cytologic examination of feces. Data were collected for a 1-year period from 82 primates, and 14 gibbons were studied intensively. White-cheeked and siamang gibbons shed Shigella flexneri sporadically, but persistently. All gibbons were affected with a mean point prevalence of 30.7% (range 0 to 71%). Shigella flexneri also was isolated from feces of lion-tailed macaques. Shigella sonnei was isolated from feces of grey-cheeked mangabeys, celebes macaques, and spider monkeys.(ABSTRACT TRUNCATED AT 250 WORDS)

Journal ArticleDOI
TL;DR: Immunohistochemical techniques are used to investigate the postnatal development of the cholecystokinin innervation of monkey prefrontal cortex to study the maturation of neurotransmitter systems in these cortical regions.
Abstract: Although the structure and function of primate prefrontal cortex undergo substantial modifications during postnatal development, relatively little is known about the maturation of neurotransmitter systems in these cortical regions. In the primate brain, cholecystokinin is present in the greatest concentrations in prefrontal regions. Thus, in this study, we used immunohistochemical techniques to investigate the postnatal development of the cholecystokinin innervation of monkey prefrontal cortex. In animals aged 4 days through adult, cholecystokinin immunoreactivity was present in nonpyramidal neurons that appeared to represent at least two distinct cell types. The most common type was a vertically oval bitufted neuron, located in layers II-superficial III, which typically had a radially descending axon that gave rise to short collaterals in layer IV. Another frequently observed cell type was a larger multipolar neuron located in the superficial half of layer III. The axon of these neurons branched locally in the vicinity of the cell body. The greatest density of cholecystokinin-containing neurons and processes was present in monkeys less than 1 month of age. The density of immunoreactive structures in every prefrontal region then progressively declined with increasing age, with the most marked changes occurring during the first postnatal year. As a result, the density of labeled neurons in adult monkeys was less than one-third of that in neonatal monkeys. However, labeled structures were significantly more dense in some ventromedial and orbital regions than in dorsal regions of the prefrontal cortex in neonatal, but not in older animals. In all animals, cholecystokinin-containing neurons were present in highest density in layers II-superficial III, and labeled terminal fields were observed in layers II, IV, and VI. In animals less than 1 month of age, fascicles of radial fibers traversed through layers III and V, whereas in animals 1 to 3 months of age, individual radial fibers rather than fiber bundles were present in layers III and V. In addition, immunoreactive pericellular arrays, which appeared to surround unlabeled nonpyramidal cells, were present in layers V and VI and the subcortical white matter in the youngest monkeys. Although many aspects of the cholecystokinin innervation of monkey prefrontal cortex remain constant during postnatal life, the distinct developmental changes in the cholecystokinin innervation of these regions suggest that it may play an important role in the maturation of the cortical circuitry that mediates the acquisition of certain cognitive abilities. © 1993 Wiley-Liss, Inc.

Journal ArticleDOI
TL;DR: The present study tested the predictions of the models in two socially housed primate species, rhesus monkeys and hamadryas baboons, representing a female-bonded and a non-female-bonding species, respectively, and found that between-group competition proved to be important with dominance a deciding factor.

Journal Article
01 Aug 1993-Leukemia
TL;DR: These animal models seem to be very suitable for the elucidation of the pathogenesis of human HTLV-I associated T-cell leukemia/lymphoma and might be further on used for therapeutical and preventative studies.
Abstract: T-cell leukemia virus-like proviral sequences (STLV-I) as well as EBV-like sequences were detected in PBLs and tissues of non-human primates (Papio hamadryas baboons, Green monkeys and Macaca arctoides; Sukhumi Primate Center/Georgia) by PCR. Surprisingly, two different types of STLV-I-Su whithin Papio hamadryas baboon were found. One of it represents the baboon prototype STLV-I-Su described earlier, present in lymphomatous baboons from the high lymphoma stock, which shows about 83% homology to HTLV-I and 85% to STLV-I in the env and tax genes

Journal Article
TL;DR: Analysis of TCR constant region genes in two non-human primate species suggests that some nucleotide substitutions occurred after the chimpanzee/human line split from the rhesus monkey line approximately 25 million yr ago, and supports the theory that specific mechanisms exist to reduce diversity in putative exon 1.
Abstract: Molecular studies in human, mouse, rat, and rabbit have demonstrated that the region of genomic DNA containing TCR C region genes has been strongly conserved during evolution To investigate the degree of conservation of this region within the primate lineage we have undertaken analysis of the TCR constant region genes in two non-human primate species Pan troglodytes (chimpanzee) and Macaca mulatta (rhesus monkey) Constant regions of TCR beta-chains were cloned and sequenced from cDNA derived from peripheral blood T cells of healthy chimpanzees and rhesus monkeys Two closely related C beta genes were characterized in each species corresponding to human C beta 1 and C beta 2 The chimpanzee/human similarity is greater than the rhesus monkey/human similarity as is expected from phylogenetic relationships The amino acid sequences of corresponding C beta genes are identical between chimpanzee and human although synonymous substitutions are present at the nucleotide level Two distinct monkey C beta 1 sequences were obtained RFLP studies using genomic DNA from individuals of both species indicated the presence of only two C beta genes in each species It is therefore likely that the rhesus monkey from which the sequence data are derived has a polymorphic C beta locus, which was also subsequently demonstrated in several other monkeys Analysis of sequence data suggests that some nucleotide substitutions occurred after the chimpanzee/human line split from the rhesus monkey line approximately 25 million yr ago These data also support the theory that specific mechanisms exist to reduce diversity in putative exon 1 Variable RFLP profiles indicated the presence of C beta polymorphism in chimpanzees and rhesus monkeys There was also evidence for a homozygous deletion of a C beta gene in one monkey, represented by the absence of one band for each digest when compared to the band patterns of other monkeys Variable intensities of the deletable band in other individuals suggest other monkeys may be heterozygous for this deletion Thus rhesus monkeys demonstrate RFLP, coding sequence, and C beta gene deletion polymorphisms, with chimpanzees also demonstrating RFLP polymorphisms of C beta

Journal ArticleDOI
TL;DR: After learning to move the cursor to contact a small target randomly appearing at four screen locations, the monkey was readily able to move a moving target in novel locations on the monitor screen.
Abstract: Summary.-In the "video-task paradigm" a subject manipulates a joy-stick to move a cursor into an experimenter-defined target area on a computer monitor, generally receiving a food reward upon completion of the task. Despite the spatial separation of the joy-stick, monitor, and location of reward delivery, the video-task paradigm has been successfully implemented with several macaque species and with chimpanzees. Prehinary attempts to implement the paradigm with squirrel monkeys, however, were not successful. This report describes successful performance by a squirrel monkey in the paradigm. After learning to move the cursor to contact a small target randomly appearing at four screen locations, the monkey was readily able to move the cursor to contacc a moving target in novel locations on the monitor screen. Recently, Rumbaugh and his associates (e.g., Rumbaugh, Richardson, Washburn, Savage-Rumbaugh, & Hopkins, 1989) have reported the successful implementation of what they term the "video-task paradigm" with rhesus monkeys (Macaca mulatta). In this paradigm the monkey controls the movement of the cursor on a computer monitor using a joy-stick. The task is to direct the cursor to an on-screen target defined by various experimental parameters; successful completion of the task results in a food reward. Contrary to earlier suggestions of the primate learning literature (e.g., Jenkins, 1943; Meyer, Treichler, & Meyer, 1965), rhesus readily learned the relationship between the joy-stick displacement and cursor movement despite the spatial separation of the joy-stick, the images on the monitor, and the food reward. Furthetmore, the monkeys could correctly move the cursor to achieve and maintain contact with a moving target. Despite the capacity of rhesus macaques, chimpanzees (Rumbaugh, 1990), and bonnet macaques (Andrews & Rosenblum, unpublished data) to master these tasks, attempts to extend these findings to squirrel monkeys have not been successful (Rumbaugh, personal communication). Other empirical data support the view that the video-task paradigm may be beyond the cognitive and learning capabilities of the squirrel monkey. In addition to the lower learning-set and discrimination reversal abilities of squirrel monkeys, their discrimination ability is particularly subject to disruption by irrelevant visual cues (e.g., encasement of stimuli in Plexiglas); they also exhibit infe

Journal ArticleDOI
01 Oct 1993-Genomics
TL;DR: Two types of retroposed sequences found in human ribosomal DNA in equivalent positions in chimpanzee, gorilla, orangutan, gibbon, and rhesus monkey rDNA are investigated, indicating fixation at different times in primate evolutionary history.

Journal ArticleDOI
TL;DR: The geriatric signs in these '~post-menopausar' monkeys 2026 years of age include drier skin, telangiectasias, tooth decay, muscle atrophy, a decrease in body weight, cataracts, and many bone and joint problems.

Journal ArticleDOI
TL;DR: The ability to use human probes to obtain cytogenetic data from Macaca species irradiated years previously or exposed to chemical clastogens makes this primate genus an excellent model for studying genetic damage.
Abstract: Chromosome painting with a probe specific for human chromosome 4 was used to «paint» monkey chromosomes in order to measure the persistence of translocations in peripheral blood lymphocytes of a rhesus monkey exposed to ionising radiation more than 25 years ago. The human probe painted the entire length of two large rhesus and cynomolgus monkey chromosomes with no cross hybridisation to other chromosomes, facilitating rapid detection of chromosome translocations in monkeys. The translocation frequency measured in one monkey was significantly higher than that for unirradiated animals. The ability to use human probes to obtain cytogenetic data from Macaca species irradiated years previously or exposed to chemical clastogens makes this primate genus an excellent model for studying genetic damage

Journal ArticleDOI
TL;DR: Differences among mAbs evidenced in tests with nonhuman primate red cells reflect the complexity of the immune reactions to the human D antigen.

Book ChapterDOI
01 Jan 1993
TL;DR: Petechiae to ecchymoses of gingiva, nasal cavity, subcutaneous tissue, and periosteum are basic lesions as vitamin C is essential to the production of collagen fibrils which are common to both vascular integrity and osteoid formation.
Abstract: The response to vitamin C deficiency differs between the various primate species. The naturally occurring disease in squirrel monkeys (Saimiri sciureus) appears to involve mainly the head region, whereas in rhesus macaques (Macaca mulatta) the disease involves the long bones, teeth, and ribs. Petechiae to ecchymoses of gingiva, nasal cavity, subcutaneous tissue, and periosteum are basic lesions as vitamin C is essential to the production of collagen fibrils which are common to both vascular integrity and osteoid formation. In the squirrel monkey, the deficiency is manifest by pericranial hemorrhage forming large hematomas. The hematomas give the animal’s head the appearance of a “turban” and stretch and distort the facial features (Fig. 219).

Journal Article
TL;DR: Results suggest that anti-T37K antibodies could be responsible for the low parasitaemia detected in immunized monkeys.
Abstract: The american primate Cebus apella has been used as an experimental model for the study of acute and chronic Chagas' disease. The antibody response elicited by 4 × 10 6 blood trypnomastigotes injected into four monkeys was analysed. Peak titres of IgM and IgG of anti-Trypanosoma cruzi antibodies were found at day 22, and between days 20 and 40 post-infection (p. i.), respectively. The ability of a Mr 37kDa (T37K) glycoprotein purified from T cruzi epimastigotes to generate IgG anti-T. cruzi antibodies in monkeys, and protect them against a challenge with trypomastigotes, was also studied. Monkeys non-immunized with T37K reached peak values of parasitaemia between days 18 and 21 post-infection, whereas immunized monkeys had lower parasitaemias without important variation

Journal Article
TL;DR: In this preliminary report the divergence times for the major primate groups are given, calculated from a study by comparative determinant analysis of 69 proteins (equaling 0.1% of the whole genetic information).
Abstract: In this preliminary report the divergence times for the major primate groups are given, calculated from a study by comparative determinant analysis of 69 proteins (equaling 0.1% of the whole genetic information). With an origin of the primate order set at 80 million years before present, the ages of the last common ancestors (LCAs) of man and the major primate groups obtained this way are as follows: Pan troglodytes 5.2; Gorilla gorilla 7.4; Pongo pygmaeus 19.2; Hylobates lar 20.3; Old World monkeys 31.4; Lagothrix lagotricha 46.0; Cebus albifrons 59.5; three lemur species 67.0, and Galago crassicaudatus 73.3 million years. The LCA results and the approach are shortly discussed. A full account of this extended investigation including results on nonprimate mammals and on the determinant structures and the immunologically derived evolutionary rates of the proteins analyzed will be published elsewhere.

Journal ArticleDOI
TL;DR: Since the appearance of Cercopithecoid having cheek pouches in early Miocene, the relative species diversity of the hominoids in the primate community has been decreasing and this dramatic change ofPrimate community in the Old World might be due to the differences in the efficiency of exploitation for the food resources in the forests between primates having and not having cheekpouches.
Abstract: Primates occupy most of the all biomass of the seed dispersors in tropical forests. Among primates, two main feeding techniques are found; one is a type of processing the fruits with cheek pouches and another is a type of swallowing the fruits without cheek pouches. The cheek pouches are one of the main morphological features of Old World monkeys, however, neither the apes nor New World monkeys have cheek pouches.Almost all of Old World monkey species have matrilineal societies, while almost of the primate not having cheek pouches have non-matrilineal societies. Some of apes and atelines have patrilineal societies.Since the appearance of Cercopithecoid having cheek pouches in early Miocene, the relative species diversity of the hominoids in the primate community has been decreasing. This dramatic change of primate community in the Old World might be due to the differences in the efficiency of exploitation for the food resources in the forests between primates having and not having cheek pouches.

Book ChapterDOI
01 Jan 1993
TL;DR: The morphology of implantation is now well described for a few primate species, including the rhesus monkey, baboon, and marmoset, and Comparisons with human implantation still depend largely on the classic studies of Hertig and Rock.
Abstract: Embryo implantation in primates relies on endocrine mechanisms that are distinct from those in nonprimate species. In all primate species studied to date, the embryo enters the uterus as a morula on day 3–4 after ovulation, hatches from the zona pellucida on day 6–8 and attaches to the maternal endometrial epithelium on day 8–9 in Old World species (1,2); day 11–12 in the marmoset monkey (3, 4) and probably day 6 in the squirrel monkey (5). The morphology of implantation is now well described for a few primate species, including the rhesus monkey (1, 6), baboon (7), and marmoset (8, 9). Comparisons with human implantation still depend largely on the classic studies of Hertig and Rock (10).