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PubMed1976

Studies on beta-crystallin from primate lens.

The major beta-crystallin fractions from the human lens and the lenses of other selected primates have been isolated and partially characterized. Primate beta-crystallins, like those of most other mammals, consist of two heterogenous protein fractions (betaH and beta L) of quite different molecular size. Most of the polypeptide chains comprising the betaH and beta L heteropolymers are common to both fractions. Evidence is presented suggesting that primate betaH-crystallin may be smaller than betaH from other vertebrate species. Additionally, human betaH is found to contain a major component on sodium dodecyl sulfate (SDS) electrophoresis which is much larger (about 60,000 daltons) than other beta-crystallin polypeptides. Immunochemical evidence inidcates that some components of primate beta-crystallin have evolved rapidly, although at least one antigenic component is very conservative and gives a reaction of identity with all other vertebrate beta-crystallins studied.

Amino Acids↗
PubMed1996

Differences in beta 3-adrenergic receptor cardiovascular regulation in conscious primates, rats and dogs.

The goal of our study was to compare the effects of two beta 3-adrenergic receptor agonists, i.e., BRL37344 (BRL) and CL316243 (CL), in conscious dogs, rats and nonhuman primates, instrumented with aortic and atrial catheters, ascending aortic flow probes and left ventricular (LV) pressure gauges. In conscious dogs, CL, 10 micrograms/kg, i.v., reduced, P < .05, mean arterial pressure by 8 +/- 4% and total peripheral resistance by 51 +/- 4% and increased, P < .05, LV dP/dt by 79 +/- 10% and heart rate by 88 +/- 8%. These responses were similar to those induced by BRL, 8.3 micrograms/kg, i.v. After autonomic blockade (beta 1/beta 2-adrenergic, cholinergic and ganglionic), CL still reduced total peripheral resistance by 49 +/- 4%, and increased LV dP/dt by 21 +/- 4%, without an effect on heart rate. In conscious rats, 10 times the dose of CL 100 micrograms/kg, i.v., reduced, P < .05, total peripheral resistance by 18 +/- 4%, without major effects on LV dP/dt and heart rate. BRL, 83 micrograms/kg i.v., reduced total peripheral resistance similarly by 31 +/- 3%, and increased heart rate (25 +/- 3%) and LV dP/dt (27 +/- 5%) more, P < .05. In conscious monkeys and baboons, CL, 100 micrograms/kg, i.v., did not induce significant effects, whereas BRL, 83 micrograms/kg, i.v., increased heart rate (36 +/- 6%), LV dP/dt (85 +/- 9%) and decreased total peripheral resistance (30 +/- 2%). After beta 1/beta 2-adrenergic receptor blockade in rats and primates, there were almost no differences between BRL and CL, i.e., in primates there were almost no significant cardiovascular effects with either compound. Both CL and BRL increased circulating free fatty acids in the dog, but not in the baboon. Thus, CL appears to be a more specific beta 3-adrenergic receptor agonist than BRL. More importantly, beta 3-adrenergic receptor stimulation was most profound in dogs, where even a direct effect on LV contractility was identified, was diminished but still significant in rats, and essentially absent in primates.

Adrenergic beta-Agonists↗
PubMed1997

Viral infections of nonhuman primates.

Approximately 53,000 serologic tests and viral isolation studies were performed on 1,700 nonhuman primate specimens for evidence of past and/or current viral infection. Information, other than the requested test, generally was not provided with the specimen. This lack of information does not permit any attempt at interpretation of results. Requested testing included a large number of diverse viral agents in approximately 40 primate species. The resulting data are in keeping with those of previous studies and offer an insight into the needs of colony management, as well as some general information on the overall frequency of infection with the indicated viruses. Inasmuch as the results represent testing of single specimens, they are not to be construed as "diagnostic," and simply indicate past infection as represented by the presence of antibody in the test animal. Viral isolation results are listed, and the number of positive results versus the number of animals tested emphasizes the limitations of the procedure. Investigations such as these continue to assist in the maintenance of healthy nonhuman primate colonies. This information also supports continued use of nonhuman primates for research in human viral infections and may be helpful in terms of animal selection for use in xenotransplants.

Animals↗
PubMed2006

Endogenous retrovirus HERV-I LTR family in primates: sequences, phylogeny, and evolution.

A human endogenous retrovirus (HERV-I; RTVL-I) has been located within the first intron of a haptoglobin-related gene. Two members of the HERV-I family were identified in proximal Yq11.2 and caused AZFa microdeletions as a result of intra-chromosomal recombination events in azoospermic patients. Using PCR25 and the sequencing approach with the genomic DNAs of primates, hominoids, Old and New World monkeys, and prosimians, the HERV-I LTR elements were identified and analysed. The LTR elements were detected only in the hominoids and the Old World monkeys, indicating that the HERV-I LTR elements were inserted into the primate genome after the split of the New World monkeys in the Oligocene era, about 33 million years ago. Nineteen members of the HERV-I LTR elements from the hominoids and the Old World monkeys showed multiple insertions or deletions. They showed a 78.6-97.4% sequence similarity to that of Hu-15 (accession no. AF290422; HERV-I LTR on human Yq11.2). The evolutionary relationships within the HERV-I LTR family among hominoids and Old World monkeys showed a random cluster, indicating that HERV-I LTR elements have evolved independently in primate evolution.

Animals↗
PubMed2024

Lineage-specific splicing regulation of MAPT gene in the primate brain.

Divergence of precursor messenger RNA (pre-mRNA) alternative splicing (AS) is widespread in mammals, including primates, but the underlying mechanisms and functional impact are poorly understood. Here, we modeled cassette exon inclusion in primate brains as a quantitative trait and identified 1,170 (&#x223c;3%) exons with lineage-specific splicing shifts under stabilizing selection. Among them, microtubule-associated protein tau (MAPT) exons 2 and 10 underwent anticorrelated, two-step evolutionary shifts in the catarrhine and hominoid lineages, leading to their present inclusion levels in humans. The developmental-stage-specific divergence of exon 10 splicing, whose dysregulation can cause frontotemporal lobar degeneration (FTLD), is mediated by divergent distal intronic MBNL-binding sites. Competitive binding of these sites by CRISPR-dCas13d/gRNAs effectively reduces exon 10 inclusion, potentially providing a therapeutically compatible approach to modulate tau isoform expression. Our data suggest adaptation of MAPT function and, more generally, a role for AS in the evolutionary expansion of the primate brain.

tau Proteins↗
PubMed2003

Occurrence of hepatitis viruses in wild-born non-human primates: a 3 year (1998-2001) epidemiological survey in Gabon.

Hepatitis B and C infections are endemic in human population in central Africa, particularly in Gabon. The aim of this study was to determine the prevalence of hepatitis B virus (HBV) and eventual occurrence of hepatitis C virus (HBC)-related strains in a variety of wild-born non-human primates living in Gabon and Congo. Plasma samples were screened for HBV and HCV markers. A non-invasive method of DNA extraction from faeces followed by specific HBV-DNA amplification was developed to study this infection in wild troops of chimpanzees and gorillas. No HCV infection in non-human primates, wild-born or captive, was detected among 596 samples tested. No HBV infection could be detected in samples tested and obtained from Cercopithecidae. In contrast, 14.7 and 42.2% of wild-born chimpanzees in Gabon and Congo were infected with HBV or had evidence of past HBV infection. At Centre International de Recherches Médicales (CIRMF) Primate Centre, 32.1% of chimpanzees and gorillas were HBV positive or had evidence of past infection. In the cases with past infection, 5.9% wild-born and 8.3% at CIRMF harboured HBV-DNA despite the presence of neutralizing HbsAb. Together with previous findings, we confirm the high HBV prevalence not only in humans but also in chimpanzees and gorillas in Gabon and Congo.

Animals↗
PubMed2001

Adaptation of the bovine spongiform encephalopathy agent to primates and comparison with Creutzfeldt-- Jakob disease: implications for human health.

There is substantial scientific evidence to support the notion that bovine spongiform encephalopathy (BSE) has contaminated human beings, causing variant Creutzfeldt-Jakob disease (vCJD). This disease has raised concerns about the possibility of an iatrogenic secondary transmission to humans, because the biological properties of the primate-adapted BSE agent are unknown. We show that (i) BSE can be transmitted from primate to primate by intravenous route in 25 months, and (ii) an iatrogenic transmission of vCJD to humans could be readily recognized pathologically, whether it occurs by the central or peripheral route. Strain typing in mice demonstrates that the BSE agent adapts to macaques in the same way as it does to humans and confirms that the BSE agent is responsible for vCJD not only in the United Kingdom but also in France. The agent responsible for French iatrogenic growth hormone-linked CJD taken as a control is very different from vCJD but is similar to that found in one case of sporadic CJD and one sheep scrapie isolate. These data will be key in identifying the origin of human cases of prion disease, including accidental vCJD transmission, and could provide bases for vCJD risk assessment.

Adaptation, Biological↗
PubMed2003

Intra- and interspecific variation of the CCR5 gene in higher primates.

We have evaluated the molecular evolution of the chemokine receptor CCR5 in primates. The chemokine receptor CCR5 serves as a major co-receptor for human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) infection. Knowledge of evolution of the CCR5 molecule and selection on the CCR5 gene may shed light on its functional role. The comparison of differences between intraspecific polymorphisms and interspecific fixed substitutions provides useful information regarding modes of selection during the course of evolution. There is marked polymorphism in the CCR5 gene sequence within different primate species, whereas sequence divergence between different species is small. By using contingency tests, we compared synonymous (SS) and nonsynonymous (NS) CCR5 mutations occurring within and between a broad range of primates. Our results demonstrate that CCR5 evolution did not follow expectations of strict neutrality at the level of the whole gene. The proportion of NS to SS at the intraspecific level was significantly higher than that observed at the interspecific level. These results suggest that most CCR5 NS polymorphisms are slightly deleterious. However, at domains more closely correlated with its known biological functions, there was no obvious evidence to support deviation from neutrality.

Animals↗
PubMed1996

Intestinal parasitism--protozoa and helminths--in primates at the Barcelona Zoo.

The faunistic results regarding intestinal parasitism by protozoa and helminths in 21 primate species (three Cebidae, thirteen Cercopithecidae, one Hylobatidae, one Lemuridae, three Pongidae) are reported. The primate species were housed in four separate galleries. Six faecal samples of each host species were subjected to coprological analysis. Fifteen parasite species were detected: 11 protozoa (Entamoeba coli, E. chattoni, E. hartmanni, Iodamoeba bütschlii, Endolimax nana, Giardia intestinalis, Chilomastix mesnilii, Enteromonas hominis, Trichomonas intestinalis, Balantidium coli, and Blastocystis hominis) and 4 helminths (Ancylostoma sp., Strongyloides fuelleborni, Strongyloides sp., and Trichuris trichiura). The results reveal certain parasitic similarities between host species housed in the same gallery; however, these primate species do not always carry identical parasite species.

Animals↗
PubMed1997

CD8+ cell-mediated immune responses: relation to disease resistance and susceptibility in lentivirus-infected primates.

Immune responses mediated by CD8+ lymphocytes have been correlated with protection from HIV infection and disease progression in humans and nonhuman primates. The CD8+ cell population is heterogeneous in terms of biological function and phenotype. We have undertaken a review of the current state of knowledge of subtypes of CD8+ cells and their role in immune responses directed to HIV and related primate lentiviruses. Differences in the pathogenesis of lentivirus infections in various primate hosts were examined and the possible roles of the various subpopulations of CD8+ lymphocytes in the resistance and/or susceptibility to lentivirus-related disease were compared.

Animals↗
PubMed1996

Preliminary examination of non-occlusal dental microwear in anthropoids: implications for the study of fossil primates.

Most studies of microscopic wear on non-human primate teeth have focused on the occlusal surfaces of molars. Recent analyses of the buccal surfaces of human cheek teeth have demonstrated an association between diet and dental microwear on the these surfaces as well. In the current study, we examine microwear on both the buccal and lingual surfaces of non-human primate molars to assess the potential of these surfaces to reveal information concerning anthropoid feeding behaviors. We compare frequency of microwear occurrence in 12 extant and 11 fossil anthropoid species. Among the living primates, the occurrence of microwear on nonocclusal surfaces appears to relate to both diet and degree of terrestriality. The implications of this research for the inference of feeding behaviors and substrate use in fossil cercopithecoids are discussed.

Analysis of Variance↗
PubMed1996

Dental microwear and microstructure in early oligocene primates from the Fayum, Egypt: implications for diet.

Textbook descriptions usually portray the Fayum anthropoideans as frugivores, with Parapithecus grangeri including a folivorous component in its diet and Apidium a component of hard-object feeding. Recent work with modern mammals has shown that analyses of both dental microwear and dental microstructure may yield insights into diet and tooth use. The purpose of this study was to combine these two techniques to gain a better perspective on the paleobiology of the Fayum higher primates. Dental microwear analyses involved the use of high resolution epoxy casts of Aegyptopithecus, Parapithecus, and Apidium housed in the Duke University Primate Center. Scanning electron micrographs were taken at x500, and all microwear features in each micrograph were digitized. For microstructure analyses, molar teeth were sectioned in a variety of planes, lightly etched, and photographed in the SEM. Results of the dental microwear analyses indicate that the three Fayum anthropoideans all clustered with modern primate frugivores but that there were also significant differences between Aegyptopithecus and the other two Fayum genera. By contrast, dental microstructure analyses showed important differences between Apidium and the other two genera. The reason for these differences probably lies in a combination of body size and dietary differences, with Aegyptopithecus occasionally feeding on hard objects and Apidium maximizing wear resistance through a unique emphasis of radial (rather than decussating) enamel.

Animals↗
PubMed1999

Constraints on masticatory system evolution in anthropoid primates.

It is well established that some observed patterns of force production in the primate masticatory system match those predicted by a simplified lever model. This model is also commonly invoked in adaptive explanations of craniodental diversity. However, systematic studies of the predictive power of this model are missing, leaving open the possibility that factors not traditionally included in the model alter the function and evolution of the masticatory system. One such factor was proposed for mammals generally by Greaves ([1978] J. Zool. (Lond.) 184:271-285), who argued that the temporomandibular joint (TMJ) was poorly suited to being pulled apart. In this constrained lever model, the avoidance of joint distraction leads to limitations on masticatory system form and function. The goal of the present study was to quantify masticatory system diversity in anthropoid primates for comparison with these predictions. Results indicate that all sampled taxa exhibit a form that is consistent with selection against regular distraction of the TMJ. Also apparent from observed patterns of scaling is a regular interaction among a limited set of cranial and dental dimensions, in accordance with the constrained model. However, the data indicate that specific positional relationships among the muscles, joints, and teeth differ from those predicted by Greaves (1978). The pattern of deviation suggests that selection has favored a conservative masticatory system configuration that safeguards the TMJ from distraction during the dynamic processing of irregular foods. The resulting buffered model leads to alternative hypotheses regarding the response of the masticatory system to dietary selection pressures. It may, therefore, improve our understanding of the adaptive significance of primate craniofacial form.

Animals↗
PubMed1998

Darting terrestrial primates in the wild: a primer.

While a goal of many field primatologists is to observe subjects in as undisturbed a setting as possible, it is often necessary to anesthetize animals for any of a variety of reasons. In this paper, we review techniques for anesthetizing wild primates, based on our experience with more than a thousand such procedures carried out on baboons in East Africa. We consider the following: 1) rationales for anesthetizing a wild primate; 2) systems for the delivery of anesthetic and choice of anesthetic; 3) the darting process itself and issues relevant to the period between darting and the safe removal of the animal; 4) handling of an anesthetized primate; 5) medical complications associated with darting; 6) when to reanesthetize an animal; 7) the process of recovery from anesthesia and release of an awake animal; 8) safety issues for humans. The range of information that can be obtained through field anesthetizations, when carried out successfully, as well as the potential benefit for the animals involved, can be enormous. However, this process is not trivial from the standpoint of the dangers involved to both the subjects and to humans and because of the potential disruption of social behavior to the group. As such, anesthetizations in the field should not be carried out without a strong rationale and without a tremendous priority given to the safety and care of all involved.

Anesthetics↗
PubMed2000

The primate cranial base: ontogeny, function, and integration.

Understanding the complexities of cranial base development, function, and architecture is important for testing hypotheses about many aspects of craniofacial variation and evolution. We summarize key aspects of cranial base growth and development in primates that are useful for formulating and testing hypotheses about the roles of the chondrocranium and basicranium in cranial growth, integration, and function in primate and human evolution. We review interspecific, experimental, and ontogenetic evidence for interactions between the cranial base and brain, and between the cranial base and the face. These interactions indicate that the cranial base plays a key role in craniofacial growth, helping to integrate, spatially and functionally, different patterns of growth in various adjoining regions of the skull such as components of the brain, the eyes, the nasal cavity, the oral cavity, and the pharynx. Brain size relative to cranial base length appears to be the dominant influence on many aspects of basicranial variation, especially the angle of the cranial base in the midsagittal plane, but other factors such as facial size, facial orientation, and posture may also be important. Major changes in cranial base shape appear to have played crucial roles in the evolution of early primates, the origin of anthropoids, and the origin of Homo sapiens.

Animals↗
PubMed2000

Grandmother hypothesis and primate life histories.

The adaptive significance of midlife menopause in human females has long engaged the attention of evolutionary anthropologists. In spite of extensive debate, the problem has only recently been examined in the context of primate life histories. Here I extend those investigations by comparing life history traits in 16 primate species to test predictions generated from life history theory. In humans, late ages of maturity and higher than expected birth rates are systematically associated with extended postmenopausal longevity. Links among these adjustments on the primate pattern can explain how selection could slow somatic senescence without favoring extension of the fertile span. This conclusion is consistent with the observation that our fertile spans are similar to those of other pongids. The shape of the argument herein demonstrates the utility of life history theory for solving problems of adaptive evolution in female life history traits, with consequences for broader arguments regarding human evolution.

Aging↗
PubMed2000

New ideas about binocular coordination of eye movements: is there a chameleon in the primate family tree?

Many animals with laterally placed eyes, such as chameleons, move their eyes independently of one another. In contrast, primates with frontally placed eyes and binocular vision must move them together so that both eyes are aimed at the same point in visual space. Is binocular coordination an innate feature of how our brains are wired, or have we simply learned to move our eyes together? This question sparked a controversy in the 19(th) century between two eminent German scientists, Ewald Hering and Hermann von Helmholtz. Hering took the position that binocular coordination was innate and vigorously challenged von Helmholtz's view that it was learned. Hering won the argument and his hypothesis, known as Hering's Law of Equal Innervation, became generally accepted. New evidence suggests, however, that similar to chameleons, primates may program movements of each eye independently. Binocular coordination is achieved by a neural network at the motor periphery comprised of motoneurons and specialized interneurons located near or in the cranial nerve nuclei that innervate the extraocular muscles. It is assumed that this network must be trained and calibrated during infancy and probably throughout life in order to maintain the precise binocular coordination characteristic of primate eye movements despite growth, aging effects, and injuries to the eye movement neuromuscular system. Malfunction of this network or its ability to adaptively learn may be a contributing cause of strabismus.

Animals↗
PubMed2001

Corticotropin-releasing hormone-binding protein in primates.

In humans, placental corticotropin-releasing hormone (CRH) production has been linked to the determination of gestational length, and a late gestational fall in CRH-binding protein (CRH-BP) has been linked to the onset of parturition. Expression of placental CRH mRNA is limited to primates, and only in man has a circulating CRH-BP been described. As the fall in CRH-BP in late gestation has been associated with parturition in humans, we sought to determine whether a CRH-BP circulated in the plasma of other primates. It is unclear whether maternal plasma CRH concentrations are elevated in New World monkeys and prosimians. We have therefore performed CRH plasma measurements in the blood of pregnant marmosets, in several species of lemur, and in pregnant and fetal rhesus monkeys as a positive control. Using gel chromatography, CRH-BP was detected in the human, gorilla, chimpanzee, orangutan, gibbon, macaque, squirrel monkey, and marmoset, but was absent in the mandrill, spider monkey, and lemur. CRH was detected in the plasma of pregnant marmosets and rhesus monkeys. CRH was also detected in the fetal rhesus monkey, but at lower concentrations than in maternal plasma. CRH immunoreactivity was not detectable in the plasma of pregnant lemurs or in extracts of lemur placenta. In conclusion, a circulating binding protein for CRH exists in all species of apes but occurs variably among New World and Old World monkeys and is absent in lemurs. The variable occurrence of the CRH-BP does not support a role for this protein in the mechanism of parturition in primates. Maternal CRH is elevated in the pregnant marmoset and rhesus, and may play a role in the pregnancy of New and Old World monkeys.

Animals↗