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PubMed1985

Structural and mechanical indicators of limb specialization in primates.

The structural mechanics of femora and humeri from primates representing a wide spectrum of habitual locomotor activities were examined to determine how cross-sectional properties vary with functional specializations of the extremities. Average bending rigidities of the midshaft of humerus and femur were measured in 60 individuals of four nonhuman primate species (Macaca nemestrina, Macaca fascicularis, Presbytis cristata, Hylobates lar) using single-beam photon absorptiometry. Linear regression analyses of the loge transformed data were used to assess the relative usage of the forelimb and hindlimb in propulsion and weight bearing, and to evaluate deviations from generalized mammalian quadrupedalism. The results suggest that average bending rigidities of the humerus and femur in primates reflect the extent to which the forelimb and hindlimb are used differently in locomotion; deviations of average bending rigidity from geometric similarity indicate functional variations from generalized mammalian quadrupedalism and the ratio of humeral to femoral bending rigidity can be used to identify trends towards hindlimb or forelimb dominance in locomotion and can be employed in general to determine how the limb was used.

Animals↗
PubMed1989

New approaches to structural evolution of limb bones in primates.

Structural analysis of primate limb bones using engineering beam theory can reduce complex biological forms to a few readily interpretable and functionally relevant parameters. Several methods of obtaining and analyzing these structural parameters are described, including computed tomography, multiple plane radiography, photon absorptiometry, and automated digital analysis. Examples of applications of these data to problems in primate adaptation and evolution include improved estimation of body mass in fossil species, investigation of relative fore- and hindlimb mechanical loadings ('dominance'), and study of more subtle within and between species differences in behavior as reflected in variations in limb bone shape. In addition, it is shown that combined analyses of diaphyseal and articular structure can provide information on aspects of structural evolution of primate limb bones not evident from independent analysis of either type of characteristic alone.

Animals↗
PubMed1991

Sexual selection, natural selection and copulatory patterns in male primates.

Complex copulatory patterns, involving multiple brief intromissions or prolonged single intromissions (PI) occur most frequently among primate species in which females mate with a number of partners (multimale and dispersed mating systems). However, the PI pattern is also confined almost exclusively to arboreal primates - to either smaller-bodied, cryptic, nocturnal species or much larger diurnal forms. Predation pressures may have limited the evolution of the PI pattern, particularly where small-bodied diurnal primates or terrestrial forms are concerned. The available evidence indicates that both sexual selection and natural selection may have influenced the evolution of copulatory patterns.

Animals↗
PubMed1991

Character phylogeny of the primate forelimb superficial venous system.

The ontogeny and comparative anatomy of the forelimb superficial veins were investigated in humans, non-human primates and other mammals. Adult humans and the orangutan (Pongo) possess two autonomous forelimb veins, one on the lateral (preaxial) margin of the limb, the other on the medial (postaxial) margin. All other adult primates and mammals examined possess a lateral vein alone. In African apes (Pan and Gorilla) and in 24% of human forelimbs the lateral vein is short, being essentially confined to the antebrachial region, whereas in other mammals and in 76% of human limbs the lateral vein runs from the carpus to the clavicular region. In humans the medial vein develops before the lateral vein, whereas in the rabbit and the pig the medial vein is present in early embryos but is subsequently lost. We propose that in humans, and probably also in the orangutan, the possession of a medial vein is a neotenic retention of a primitive tetrapod condition. These animals, which retain their medial vein, are united by losing a late stage in their ontogeny. Other animals subsequently pass through a stage in which the medial vein is lost, but Pongo and Homo retain this vein to adulthood. The loss of an ontogenetic stage can arise independently, and the presence of a medial vein therefore affords only weak evidence for a close phylogenetic relationship between humans and the orangutan. The polymorphic lateral vein of humans may be a character state that is intermediate between the derived (short) lateral vein of the African apes and the primitive long lateral vein of other non-human primates and mammals.

Animals↗
PubMed1996

Basic neurophysiology of primate locomotion.

To initiate and terminate bipedal and quadrupedal locomotor movements, a smooth transition to and from standing is necessary. For this, integration of postural and locomotor control systems is required. Recent studies in nonhuman primates and other quadrupedal animals such as cats have clearly shown that there exist significant analogies between the primate species investigated (Macaca mulatta, Macaca fascicularis, and marmosets) and the cats regarding the spinal stepping generator or central pattern generator (CPG), supraspinal descending pathways which activate CPG, and the midbrain and brain stem postural and locomotor control structures. Further studies aimed at elucidating the differences and similarities in the manner of locomotor control among different animal species will help us in understanding the control mechanisms involved in both bipedal and quadrupedal locomotor movements in nonhuman primates.

Animals↗
PubMed1996

Utilization of available films and records of primates with central nervous system lesions.

For many decades, ablation experiments were used to evaluate the function of central nervous system structures in primates. The use of this technique has greatly diminished with the development of neuronal unit recording. Nevertheless, the available films and written descriptions from prior ablation studies can still be used to further our understanding of: (1) the functional organization of the primate brain; (2) the differences in function between similar cerebral structures in primates and other mammals, and (3) ontogenetic changes in the functional characteristics of cerebral structures. We are in the process of making some of the films and records from these prior studies available to interested scientists.

Animals↗
PubMed1978

Immunological relationships of human and subhuman primate pregnancy-associated plasma proteins.

(1) Four pregnancy-associated plasma proteins cross-reactive with antibodies to the human pregnancy proteins were detected in several species of pregnant subhuman primates. In the case of the two apes studied (chimpanzee and orangutan), these appeared to be immunologically identical to the human PAPPs (PAPP-A, -B, -C, and HCS). In the old world monkeys analyzed, equivalent partially cross-reactive PAPPs were found; while in the new world squirrel monkey, only faint traces of cross-reactive PAPP-C and HCS were observed with the most sensitive methods used. (2) As in the human, these proteins appeared to be specific for pregnancy, not being detectable in nonpregnant animals, female or male. (3) The pregnant chimpanzee possessed significantly higher concentrations of PAPP-A and PAPP-C than did women at an equivalent stage of pregnancy, while the HCS and PAPP-B levels appeared to be approximately the same. (4) The primate PAPP-C analogues were more complex than human PAPP-C, often revealing multiple gel diffusion patterns with subfractions of differing electrophoretic mobilities. (5) Based on the changes of electrophoretic mobility upon exposure to neuraminidase, the subhuman primate as well as human PAPP-A and PAPP-C appeared to be glycoproteins containing sialic acid. (6) In the chimpanzee and rhesus monkey, as in the human, the levels of PAPP-A, PAPP-C, and HCS were appreciably higher during the third trimester of pregnancy than they were during the second trimester.

Animals↗
PubMed1978

Chemical and physical restraint of nonhuman primates.

Numerous publications on primate restraint and anesthesiology have appeared in recent years. This reflects the striking growth of interest in medical primatology and of efforts to improve restraint agents and methods to facilitate humane use of primates in research. For access to earlier literature, readers should consult recent textbooks [12; 29, pp. 469--474], reviews on chemical or physical restraint [3, 4, 16, 27, 30, 37], and other valuable publications on these subjects that have appeared since 1965 [1, 20, 23, 36, 40, 42]. In this brief review we consider publications, principally since 1971, that deal with chemical or physical restraint. We also present previously unpublished data on the clinical use in primates of CI 744 (Telazol), a new dissociative anesthetic that until recently has been available only for investigational use.

Alfaxalone Alfadolone Mixture↗
PubMed1981

Pregnancy monitoring in diverse primate species by estrogen and bioactive luteinizing hormone determinations in small volumes of urine.

Immunoreactive estrogen and luteinizing hormone/chorionic gonadotropin (LH/CG) bioactivity have been measured throughout pregnancy in diverse primate species with a sample methodological approach utilizing small volumes of urine collected randomly. Total immunoreactive estrogen levels and the relative abundance of component estrogens (estrone, estradiol and estriol) at various stages of gestation were compared in the human, orangutan, pygmy chimpanzee, Douc langur and capuchin. Measurement of urinary LH/CG bioactivity enables an earlier detection of pregnancy when compared to the nonhuman primate pregnancy test. The methods described provide a practical and non-stressful way to detect and monitor pregnancy in widely divergent primate species.

Animals↗
PubMed1980

A comparative study of rosette formation in 12 species of nonhuman primates.

Lymphocytes, isolated from the peripheral blood of 12 species of nonhuman primates, were tested for the ability to form rosettes with antibody-complement-coated erythrocytes (EAC rosettes) and with erythrocytes from various animal species. In general, New World primates (wooly, spider colobus, capuchin and owl monkeys) had a greater number of EAC rosette-forming cells (30-44%) than did Old World monkeys (baboons, gibbons, rhesus, cynomolgus, pigtailed, stumptailed and Japanese macaques) (22-30%). All possessed lymphocytes capable of forming rosettes with sheep erythrocytes. Lymphocytes from some primate species formed rosettes with canine, equine, goat or porcine erythrocytes.

Animals↗
PubMed1999

Analog VLSI-based modeling of the primate oculomotor system.

One way to understand a neurobiological system is by building a simulacrum that replicates its behavior in real time using similar constraints. Analog very large-scale integrated (VLSI) electronic circuit technology provides such an enabling technology. We here describe a neuromorphic system that is part of a long-term effort to understand the primate oculomotor system. It requires both fast sensory processing and fast motor control to interact with the world. A one-dimensional hardware model of the primate eye has been built that simulates the physical dynamics of the biological system. It is driven by two different analog VLSI chips, one mimicking cortical visual processing for target selection and tracking and another modeling brain stem circuits that drive the eye muscles. Our oculomotor plant demonstrates both smooth pursuit movements, driven by a retinal velocity error signal, and saccadic eye movements, controlled by retinal position error, and can reproduce several behavioral, stimulation, lesion, and adaptation experiments performed on primates.

Adaptation, Physiological↗
PubMed1995

Immunoglobulin prevents complement-mediated hyperacute rejection in swine-to-primate xenotransplantation.

Immunoglobulins regulate the complement system by activating complement on foreign surfaces and diverting reactive complement proteins away from autologous cell surfaces. Based on this model, we explored the ability of Ig to balance complement activation versus control in a pig-to-primate cardiac xenotransplantation model in which the binding of xenoreactive antibodies of the recipient to graft blood vessels and the activation of complement cause hyperacute rejection. Human IgG added to human serum caused a dose-dependent decrease in deposition of iC3b, cytotoxicity, and heparan sulfate release when the serum was incubated with porcine endothelial cells. This decrease was not caused by alteration in antibody binding or consumption of complement but presumably reflected decreased formation of C3 convertase on the endothelial cells. Infusion of purified human IgG into nonhuman primates prevented hyperacute rejection of porcine hearts transplanted into the primates. As expected, the transplants contained deposits of recipient Ig and C1q but not other complement components. The inhibition of complement on endothelial cell surfaces and in the xenotransplantation model supports the idea that IgG regulates the classical complement pathway and supports therapeutic use of that agent in humoral-mediated disease.

Animals↗
PubMed1979

Comparative enamel histology of primate teeth.

The use of nonhuman primates as experimental models has markedly increased during the past decade. However, very little is known about primate dental tissues, especially enamel. Comparative studies of the enamel from 25 primate species reveal a wide variation in (1) the thickness of enamel, (2) microstructure and ultrastructure, and (3) the species' capacity to respond to systemic stress. These data provide a baseline of information presently not available to the dental researcher.

Animals↗
PubMedDate not supplied

The evolutionary basis of some clinical disorders of the human foot: a comparative survey of the living primates.

The living primates are a highly diverse group of essentially arboreal animals whose feet are variously adapted for grasping, climbing, and leaping in trees. One of the most remarkable aspects of the anatomical variation in the feet of the extant primates is that this diversity can be arranged in a graduated sequence ranging from the primitive transtarsal-opposition type of grasping foot found in the lemurs, through the specialized transmetarsal-adduction type that characterizes the higher primates, to the unique nongrasping foot of humans. The comparative study of this graded series makes it possible, without recourse to the fossil record, to appreciate the adaptive and functional stages through which the human foot passed in its evolution. It is hypothesized that the initial stage of human erect posture was characterized by a foot which was adapted to both hallucial grasping and short distance bipedal walking. In many respects, the structure of the foot of this primitive human was probably similar to that of the living highland gorilla. When compared with the feet of our closest living relatives, the African apes, the human foot is characterized by two major evolutionary specializations: the longitudinal and transverse arches, and the parallel first and second metatarsals. These two morphological adaptations, together with several associated specializations, are the structural basis of the bipedal human foot. Reconstructing the evolutionary and adaptive history of these specializations creates a better understanding of some of the more common clinical podiatric disorders. The modern human foot is structurally so well adapted to prolonged bipedal walking and standing that even slight deviations from its evolutionarily established pattern will produce debilitating clinical manifestations. In most cases, successful treatment of such disorders involves restoration of the foot's basic adaptive configuration.

Adaptation, Biological↗
PubMed2005

Leveraging human genomic information to identify nonhuman primate sequences for expression array development.

BACKGROUND: Nonhuman primates (NHPs) are essential for biomedical research due to their similarities to humans. The utility of NHPs will be greatly increased by the application of genomics-based approaches such as gene expression profiling. Sequence information from the 3' end of genes is the key resource needed to create oligonucleotide expression arrays. RESULTS: We have developed the algorithms and procedures necessary to quickly acquire sequence information from the 3' end of nonhuman primate orthologs of human genes. To accomplish this, we identified terminal exons of over 15,000 human genes by aligning mRNA sequences with genomic sequence. We found the mean length of complete last exons to be approximately 1,400 bp, significantly longer than previous estimates. We designed primers to amplify genomic DNA, which included at least 300 bp of the terminal exon. We cloned and sequenced the PCR products representing over 5,500 Macaca mulatta (rhesus monkey) orthologs of human genes. This sequence information has been used to select probes for rhesus gene expression profiling. We have also tested 10 sets of primers with genomic DNA from Macaca fascicularis (Cynomolgus monkey), Papio hamadryas (Baboon), and Chlorocebus aethiops (African green monkey, vervet). The results indicate that the primers developed for this study will be useful for acquiring sequence from the 3' end of genes for other nonhuman primate species. CONCLUSION: This study demonstrates that human genomic DNA sequence can be leveraged to obtain sequence from the 3' end of NHP orthologs and that this sequence can then be used to generate NHP oligonucleotide microarrays. Affymetrix and Agilent used sequences obtained with this approach in the design of their rhesus macaque oligonucleotide microarrays.

Algorithms↗
PubMed2001

Use of molecular beacons to verify that the serine hydroxymethyltransferase pseudogene SHMT-ps1 is unique to the order Primates.

BACKGROUND: The serine hydroxymethyltransferase processed pseudogene SHMT-ps1 has been suggested to be unique to the order Primates because of the failure to amplify this sequence by PCR from genomic DNAs of any non-primate mammal species. Here, 'molecular beacon' probes specific to SHMT-ps1 were used in an attempt to verify this suggestion. RESULTS: In a search for SHMT-ps1-specific sequences using molecular beacons across a range of mammalian species, SHMT-ps1 was only found in primates. The molecular beacon assays also showed that SHMT-ps1 is present in both Old World and New World species but not among prosimians. CONCLUSIONS: These results suggest that SHMT-ps1 originated close to the origin of the Anthropoidea, some 40 to 50 million years ago.

Animals↗
PubMed2006

Primate-specific evolution of an LDLR enhancer.

BACKGROUND: Sequence changes in regulatory regions have often been invoked to explain phenotypic divergence among species, but molecular examples of this have been difficult to obtain. RESULTS: In this study we identified an anthropoid primate-specific sequence element that contributed to the regulatory evolution of the low-density lipoprotein receptor. Using a combination of close and distant species genomic sequence comparisons coupled with in vivo and in vitro studies, we found that a functional cholesterol-sensing sequence motif arose and was fixed within a pre-existing enhancer in the common ancestor of anthropoid primates. CONCLUSION: Our study demonstrates one molecular mechanism by which ancestral mammalian regulatory elements can evolve to perform new functions in the primate lineage leading to human.

Amino Acid Motifs↗
PubMed2003

Behavioral abnormalities in captive nonhuman primates.

In this study, we dealt with 11 species of nonhuman primates across 10 zoos in India. We recorded behavior as instantaneous scans between 9 a.m. and 5 p.m. In the study, we segregated behaviors for analyses into abnormal, undesirable, active, and resting. The 4 types of abnormal behavior exhibited included floating limb, self-biting, self-clasping, and stereotypic pacing. In the study, we recorded 2 types of undesirable behavior: autoerotic stimulation and begging. Langurs and group-housed macaques did not exhibit undesirable behaviors. A male lion-tailed macaque and a male gibbon exhibited begging behavior. autoerotic stimulation and self-biting occurred rarely. Males exhibited higher levels of undesirable behavior than did females. Animals confiscated from touring zoos, circuses, and animal traders exhibited higher levels of abnormal behaviors than did animals reared in larger, recognized zoos. The stump-tailed macaque was the only species to exhibit floating limb, autoerotic stimulation, self-biting, and self-clasping. Our results show that rearing experience and group composition influence the proportions of abnormal behavior exhibited by nonhuman primates in captivity. The history of early social and environmental deprivation in these species of captive nonhuman primates probably is critical in the development of behavioral pathologies. Establishing this will require further research.

Animals↗