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PubMed1983

The evolution of monogamy in primates.

The evolution of primate monogamy is described as an ordered sequence of choices by generalized, hypothetical females and males. Females first choose whether or not to associate with other females. Predators encourage gregariousness in diurnal primates; however, nocturnality or scarce and evenly distributed food supplies may enforce separation. A testable group size model based on food patch size is developed and qualitatively supported. If females choose solitude, males then choose either to defend a single female and invest in her offspring, or to compete with other males for access to several females, usually by defending a territory or establishing dominance over the home ranges of several females. The decision rests on the defensibility of females and on the availability of an effective form of male parental investment. Both of these factors are dependent on local female population density. A model is developed that assumes that territorial defense is the principal form of male parental investment, and it predicts that monogamy should occur at intermediate densities: at high densities, males should switch to defense of multiple females, and at low densities there is no investment value in male territorial defense. The model is shown to be only partly adequate. Variation in local population densities prevents the establishment of obligate monogamy through territoriality in small monkeys, since male territorial behavior is inconsistent over the long run. Here, carrying of offspring by males can succeed territoriality, providing an effective and reliable form of parental investment to maintain the pair bond in the face of population fluctuations and changes in group structures. This hypothesis is supported by the scarcity of obligate monogamy among the prosimians, which frequently do not carry their young.

Animals↗
PubMed1984

Angiotensin II receptors of human and primate adrenal fasciculata and glomerulosa: correlations of binding and steroidogenesis.

Subcellular fraction and collagenase-dispersed isolated adrenal fasciculata and glomerulosa cells from human and primate adrenal glands and cortisol-producing tumors have been utilized to study angiotensin II (Ang II) receptors and steroid biosynthesis. The receptor density of glomerulosa was threefold higher than that fasciculata. A benign cortisol-producing adenoma did not differ from normal fasciculata, but a malignant tumor had significantly lower affinity binding. Agonist and antagonist analogues of Ang II competed for binding sites commensurate with known biologic activity. The Kd Analogue binding also had corresponding changes in cortisol biosynthesis. The ED50 for aldosterone biosynthesis by glomerulosa cells was significantly lower at 55 pmol/L. Fewer receptors in human fasciculata as compared to glomerulosa and a less sensitive response to Ang II are consistent with previous in vitro observations in other species. These studies suggest that there may be a biologically relevant Ang II receptor of human and primate adrenal fasciculata that share many characteristics with the receptor of the glomerulosa.

Adenoma↗
PubMed1977

Dicentric yields induced by gamma-radiation and chromosome arm number in primates.

To evaluate the effect of the chromosome arm number on the yield of dicentric chromosomes, frequencies of gamma-ray-induced chromosome aberrations were examined with peripheral lymphocytes from three different primate species, Saimiri sciureus (arm number, 77), Macaca fascicularis (arm number, 83) and Nycticebus coucang (arm number, 99). Irradiated blood samples were cultured by the same standard technique as that commonly used for human lymphocytes. The yields of dicentrics and dicentrics plus rings at doses of 100, 200 and 300 rad of gamma-irradiation were not significantly different among the three species, in spite of the difference in the chromosome arm number. Furthermore, dose-response relationships for these species were consistent with that for man. Statistical analysis indicated that the expected dicentric yields calculated from the arm number model were significantly different from the observed yields at 200 and 300 rad doses (P less than 0.01). From these results it can be pointed out that there is no correlation between the yield of dicentrics and the effective chromosome arm number, and that the chromosomal radiosensitivity of these primates is essentially the same as that of man, at least in the lymphocyte system.

Animals↗
PubMed1993

Accumulation of cardiac lipofuscin in crab-eating monkeys (Macaca fasicularis): the same rate of lipofuscin accumulation in several species of primates.

Previously, we have reported that the aging process begins at sexual maturation (Nakano, M. et al., Mech. Ageing Dev., 52 (1990) 93-106). In this paper, we reported the cardiac lipofuscin accumulation of crab-eating monkeys. The first appearance of cardiac lipofuscin was around sexual maturation, and the rate of accumulation in crab-eating monkey was 0.45. Several primates which have different life spans show the same rate of lipofuscin accumulation in the life stage. Namely, even in a different life span, the amount of lipofuscin accumulation in a given period of life such as puberty, middle age, old age was the same. From these results, it is suggested that the amount of lipofuscin accumulation is the same in the life span of primates having different life spans.

Aging↗
PubMed1988

The human X-linked steroid sulfatase gene and a Y-encoded pseudogene: evidence for an inversion of the Y chromosome during primate evolution.

The mammalian X and Y chromosomes are thought to have evolved from a common, nearly homologous chromosome pair. Although there is little sequence similarity between the mouse or the human X and Y, there are several regions in which moderate to extensive sequence homologies have been found, including, but not limited to, the so-called pseudoautosomal segment, in which X-Y pairing and recombination take place. The steroid sulfatase gene is in the pseudoautosomal region of the mouse, but not in man. We have cloned and characterized the human STS X-encoded locus and a pseudogene that is present on the long arm of the Y chromosome. Our data in humans and other primates suggest that there has been a pericentric inversion of the Y chromosome during primate evolution that has disrupted the former pseudoautosomal arrangement of these genes. These results provide additional insight into the evolution of the sex chromosomes and into the nature of this interesting portion of the human genome.

Animals↗
PubMedDate not supplied

Current topic: structural responses of the primate endometrium to implantation.

Morphological responses to implantation and pregnancy in the human and nonhuman primates include decidualization of the endometrial fibroblasts and accumulation of large numbers of large granular lymphocytes, formerly called endometrial granular cells, and may also include an epithelial plaque response and endothelial cell hypertrophy. Although stromal decidualization occurs in all species, it develops slower in macaques than in the human, and slower in the baboon than in the macaques. Cytologically, however, in all of these species there is extensive modification of the decidual cells by midgestation. Hypertrophy of luminal and gland neck epithelial cells is common in most monkeys and is also seen in the baboon, but has not been reported in humans. Large granular lymphocytes undergo changes in morphology during the first week after implantation in the rhesus monkey, the only species in which they have been studied in the immediate postimplantation period. Later in pregnancy many of the large granular lymphocytes are surrounded by decidual cells in this species. All of the responses can be elicited by trauma and appropriate hormonal conditions, but the epithelial plaque response forms first in the rhesus monkey and baboon. It is suggested that more complete fine structural and immunocytochemical studies of the different decidual regions at different gestational ages, combined with studies of the synthetic and antigenic nature of the different cell types, would allow determination of whether or not there are subpopulations of decidual cells in primates as well as suggesting possible functions of the cells in pregnancy.

Animals↗
PubMed1995

Anatomic basis of cognitive-emotional interactions in the primate prefrontal cortex.

Recognition that posterior basal and medial parts of the prefrontal cortex belong to the cortical component of the limbic system was important in understanding their anatomic and functional organization. In primates, the limbic system has evolved along with the neocortex and maintains strong connections with association areas. Consequently, damage to limbic structures in primates results in a series of deficits in cognitive, mnemonic and emotional processes. Limbic cortices differ in their structure and connections from the eulaminate areas. Limbic cortices issue widespread projections from their deep layers and reach eulaminate areas by terminating in layer I. By comparison, the eulaminate areas receive projections from a more restricted set of cortices and when they communicate with limbic cortices they issue projections from their upper layers and terminate in a columnar pattern. Several of the connectional and neurochemical characteristics of limbic cortices are observed as a transient feature in all areas during development. Anatomic evidence suggests that limbic areas retain some features observed in ontogeny, which may explain their great plasticity and involvement in learning and memory, but also their preferential vulnerability in several psychiatric and neurologic disorders.

Animals↗
PubMed1990

Primate social behavior--anxiety or depression?

A review of primate social behavior in different species is presented, with particular emphasis on the talapoin monkey and the concept of dominance and how this may be related to physiological function. Social behavior in nonhuman primates can be used to study both anxiety and depression, depending on the precise social setting employed and the way in which the animals are manipulated, for example by drugs. Studies relevant to anxiety and depression are described, and indicate that the behavior of dominant animals is more susceptible to drugs that are known to manipulate levels of anxiety, whereas subordinate animals appear more susceptible to treatment with antidepressant drugs.

Animals↗
PubMed1993

Cross-reactivity of 75 monoclonal antibodies to human immunoglobulin with sera of non-human primates.

We systematically analyzed a panel of 75 murine monoclonal antibodies (mAbs) reactive with human immunoglobulins IgG, IgA, IgM, IgD, and kappa and lambda light chains for reactivity with serum immunoglobulins of higher primates. In the great apes, and to a lesser extent in other primates, epitopes related to human light chains, IgM, IgA, IgD, and all 4 IgG subclasses were identified with many of the mAbs. Those mAbs identified as reactive with a given species may be useful for immunologic studies of these species. Cladistic analysis of antigenic relatedness generated a phylogenetic tree consistent with current anatomic or molecular taxonomies.

Animals↗
PubMed1986

The causes of false-positives encountered during the screening of old-world primates for antibodies to human and simian retroviruses by ELISA.

Sera from 526 old-world primates representing 50 different species were screened by ELISA for antibodies to human T-lymphotropic viruses I and III, and simian retrovirus type 1 (SRV-1). About one-fourth of the sera were positive by ELISA. There was a tendency, however, for the same sera to be positive for all three human and simian retroviruses. Only about one in five of the ELISA antibody-positive sera were confirmed to be positive by Western blotting. False-positive ELISA antibody tests were particularly common among sera from mandrills, crab-eating macaques, lion-tailed macaques, African green monkeys, and DeBrazza's and moustached guenons. Sera that were falsely positive in ELISA antibody tests to the three human and simian retroviruses were found to contain antibodies that reacted at comparable intensity with feline leukemia, infectious peritonitis and panleukopenia viruses. The false anti-viral activity of these sera was found to be due to antibodies that reacted with non-viral proteins that were copurified with all five virus preparations. These proteins were present in normal cat and human cells used to grow the various viruses and in gelatin. The implications of nonspecific cell-protein antibodies in primate sera were discussed in the light of this and previous seroepidemiologic studies of man and old-world monkeys.

Animals↗
PubMed1991

Dopaminergic innervation of the cerebral cortex: unexpected differences between rodents and primates.

Until recently, views on the organization and role of the mesotelencephalic dopaminergic (DA) systems were mostly based on studies of rodents, and it was assumed that homology existed across mammalian species. However, recent studies of both human and non-human primates indicate that this might not be so. The mesocortical DA system in primates, which is directly involved in the pathophysiology of severe illnesses such as Parkinson's disease and psychoses, shows substantial differences from that of rodents. These differences include much larger, re-organized terminal fields, a different phenotype for the co-localization of neuropeptides and a very early prenatal development.

Animals↗
PubMed1994

A third parallel visual pathway to primate area V1.

Recent studies of the primate visual system have focused on the proposal that the perception of form and motion are processed by two parallel pathways that originate from separate populations of cells in the retina. Earlier proposals for parallel processing of visual signals identified a third pathway that could be traced from the retina to the visual cortex. This third pathway was assumed to be unimportant. A growing body of evidence suggests that this pathway to cortex is distinct anatomically, physiologically and neurochemically, and is well represented in primates. These findings raise new and interesting questions not only about the role of this pathway, but also about the intracortical integration of afferent parallel signals.

Animals↗
PubMed1993

The biologic importance of conserved major histocompatibility complex class II motifs in primates.

Phylogenetic comparisons of polymorphic second-exon sequences of MHC class II DRB genes showed that equivalents of the HLA-DRB1*03 alleles are present in various nonhuman primate species such as chimpanzees, gorillas, and rhesus macaques. These alleles must root from ancestral structure(s) that were once present in a progenitor species that lived about 35 million years ago. Due to accumulation of genetic variation, however, sequences that cluster into a lineage are generally unique to a species. To investigate the biologic importance of such conservation and variation, the peptide-binding capacity of various Mhc-DRB1*03 lineage members was studied. Primate Mhc-DRB1*03 lineage members successfully binding the p3-13 peptide of the 65-kD heat-shock protein of Mycobacterium tuberculosis/leprae share a motif that maps to the floor of the peptide-binding site. Apart from that, some rhesus macaque MHC class-II-positive cells were able to present the p3-13 peptide to HLA-DR17-restricted T cells whereas cells obtained from great ape species failed to do so. Therefore, these studies open ways to understand which MHC polymorphisms have been maintained in evolution and which MHC residues are essential for peptide binding and T-cell recognition.

Amino Acid Sequence↗
PubMed1990

Axenic isolation of Giardia strains from primates and rodents.

During the examination of animals at the Poznan Zoological Gardens, attempts were made to isolate Giardia strains. Using an in vitro excystation procedure, eight samples of cysts from animals with asymptomatic giardiasis were inoculated on BI-S-33 medium. The ease of isolation and axenization of Giardia was surprising; five axenic isolates of Giardia, belonging to the G. duodenalis morphological group, were established from primates (slow loris, lesser slow loris and siamang) and from rodents (Gambian giant pouched rat and cuis). The growth of all isolates was abundant and similar; the peak number of trophozoites on the seventh day (depending on the Giardia isolate) was 2.3 X 10(6)-3.2 X 10(6) and generation times were 8.2-19.3 h. The easy establishment of these isolates confirmed that they belong to the G. duodenalis morphological group. The recent hypothesis that Giardia may be introduced to a human population from an animal source implies the necessity to isolate and differentiate parasite strains from various hosts. In this respect, the first isolation of Giardia strains from non-human primates and from rodents is of particular importance.

Animals↗
PubMed1992

Vitamin C--the primate fertility factor?

The loss of the ability of primates and man to synthesise ascorbic acid (vitamin C) is usually seen as an evolutionary accident, with no benefit to the species. This paper argues that the loss of this biosynthetic ability has allowed vitamin C to act as a 'fertility factor' in primate societies. It is argued that the requirement for vitamin C increases with age, and so in times of food shortages the older members of society suffer higher mortality than the younger. This reduces the median age of the population towards the younger and most fertile members, and so enables the population to regrow rapidly when food resources are restored.

Aging↗
PubMed1984

Evolution of butyrylcholinesterase in higher primates: an immunochemical study.

Serum butyrylcholinesterase (BuChE; EC 3.1.1.8) of man and the higher primates was tested enzymatically and immunochemically, with the aid of monoclonal antibodies (McAb) developed against the enzyme isolated from human blood. Enzyme activities showed great differences across species and among individuals, but all samples tested were dibucaine-sensitive. One McAb showed similar affinities for BuChE of each species, but another showed marked differences in affinity, preferring species in the order: man greater than chimpanzee = pygmy chimpanzee greater than gorilla much greater than orangutan greater than gibbon. We conclude that at least one epitope of BuChE underwent progressive modification during the later stages of primate evolution.

Animals↗
PubMed1990

Molecular cytotaxonomy of primates by chromosomal in situ suppression hybridization.

A new strategy for analyzing chromosomal evolution in primates is presented using chromosomal in situ suppression (CISS) hybridization. Biotin-labeled DNA libraries from flow-sorted human chromosomes are hybridized to chromosome preparations of catarrhines, platyrrhines, and prosimians. By this approach rearrangements of chromosomes that occurred during hominoid evolution are visualized directly at the level of DNA sequences, even in primate species with pronounced chromosomal shuffles.

Animals↗
PubMed1994

Relationship between QaT and RR intervals in rats, guinea pigs, rabbits, and primates.

The ECG is routinely used in many species to monitor effects of drugs. While it is relatively easy to measure both PR and QRS, measurement of QT is complicated by the fact that this interval can change with heart rate. In order to compensate for variations in QT due to variations in heart rate, various correction factors have been used, including those of Bazett and Hodges. Such corrections were devised for humans and may have limited applicability in other species. We have systematically varied heart rate in anesthetized rats, guinea pigs, rabbits, and primates using procedures such as vagal stimulation, direct atrial stimulation, injection of cold saline and drugs, including anesthetics, and measured the resulting QT (as QaT and related measures). Over a wide range of heart rates we tested various formulas for their value in correcting for the variation in QT interval associated with changes in heart rate. In rats the "QT" interval did not change appreciably with heart rate. In the other species QaT intervals varied in the expected manner with heart rate in that they decreased with tachycardia and increased with bradycardia. Various formulas were tested for their utility in correcting measures of the QaT interval (QaTc) for changes in heart rate in guinea pigs, rabbits, and primates. In species other than rats, there was little difference between the various formulas in their ability to increase the precision of QaTc and the normality of its distribution, although the best correction is that derived from the regression (either linear, square root, or polynomial) equation relating RR and QaT.

Animals↗