Species-specific distributions of tyrosine hydroxylase–immunoreactive neurons in the prefrontal cortex of anthropoid primates

In this study, we assessed the distribution of cortical neurons immunoreactive for tyrosine hydroxylase (TH) in prefrontal cortical regions of humans and nonhuman primate species. Immunohistochemical methods were used to visualize TH-immunoreactive (TH-ir) neurons in areas 9 (dorsolateral prefrontal cortex) and 32 (anterior paracingulate cortex). The study sample included humans, great apes (chimpanzee, bonobo, gorilla, orangutan), one lesser ape (siamang), and Old World monkeys (golden guenon, patas monkey, olive baboon, moor macaque, black and white colobus, and François' langur). The percentage of neurons within the cortex expressing TH was quantified using computer-assisted stereology. TH-ir neurons were present in layers V and VI and the subjacent white matter in each of the Old World monkey species, the siamang, and in humans. TH-ir cells were also occasionally observed in layer III of human, siamang, baboon, colobus, and François' langur cortex. Cortical cells expressing TH were notably absent in each of the great ape species. Quantitative analyses did not reveal a phylogenetic trend for percentage of TH-ir neurons in these cortical areas among species. Interestingly, humans and monkey species exhibited a bilaminar pattern of TH-ir axon distributions within prefrontal regions, with layers I–II and layers V–VI having the densest contingent of axons. In contrast, the great apes had a different pattern of laminar innervation, with a remarkably denser distribution of TH-ir axons within layer III. It is possible that the catecholaminergic afferent input to layer III in chimpanzees and other great apes covaries with loss of TH-ir cells within the cortical mantle

Orexinergic bouton density is lower in the cerebral cortex of cetaceans compared to artiodactyls

The species of the cetacean and artiodactyl suborders, which make up the cetartiodactyl order, have very different arousal thresholds and sleep-wake systems. The aim of this study was to determine whether cetaceans or artiodactyls have differently organized orexinergic arousal systems by examining the density of orexinergic innervation to the cerebral cortex. This study provides a comparison of orexinergic bouton density in the cerebral cortex of twelve cetartiodactyl species by means of immunohistochemical staining and stereological analysis. It was observed that the morphology of the axonal projections of the orexinergic system to the cerebral cortex was similar across all species, as the presence, size and proportion of large and small orexinergic boutons were similar. Despite this, orexinergic bouton density was lower in the cerebral cortex of cetaceans compared to artiodactyls, even when corrected for brain mass, neuron density, glial density and glial: neuron ratio. Glial density was identified as the major determinant for the observed differences. It appears a synergy exists between the orexinergic neurons and their projections, glial cells, and the biochemical correlates of appetitive drive and arousal, but further studies need to be performed to understand the full extent of the orexinergic system and its role in sustained arousal.This work was mainly supported by funding from the South African National Research Foundation (P.R.M., N.C.B.) and by a fellowship within the Postdoctoral-Program of the German Academic Exchange Service, DAAD (N.P.). The work was also supported by an IOER R&G Grant from Des Moines University (#12- 13-03) (M.A.S.), Reykjavik University 2010 Development Fund (K.Æ.K.), the Deanship of Scientific Research at the King Saud University through the research group project number RGP_020 (A.N.A., O.B.M.), and NIH grant DA 2R01MH064109 and the Department of Veterans Affairs (J.M.S).http://www.elsevier.com/locate/jchemneu2016-10-31hb2016Mammal Research InstituteZoology and Entomolog

Spatio-Temporal Aspects of Gated Residential Security Estates in Non-metropolitan Western Cape

Gated developments have long been a subject of research the world over. Most international and South African studies have focused on gated developments within the metropolitan sphere, with very few studies done on non-metropolitan gated developments. This research attempts to address this research gap by focusing on the spatio-temporal aspects of non-metropolitan gated residential security estates in the Western Cape Province. It was found that most non-metropolitan gated residential security estates were located in settlements along the coast and/or in close proximity to the metropolitan area of Cape Town. Furthermore, the first half of the first decade of the twenty first century witnessed the planning authorisation approval of more than two thirds of all non-metropolitan gated residential security estates. While the locational and temporal aspects of non-metropolitan gated residential security estates in the Western Cape Province are discussed in this paper, there remain a number of avenues for further research into the phenomenon of non-metropolitan gated developments. © 2011 Springer Science+Business Media B.V.Articl

Using geospatial data analysis and qualitative economic intelligence to inform local economic development in small towns: a case study of Graaff-Reinett, South Africa

Lettere En WysbegeerteGeografie En OmgewingstudiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

Towards generic interventions to stimulate growth potential in small towns of the Western Cape province, South Africa

Lettere En WysbegeerteGeografie En OmgewingstudiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

Non-metropolitan Growth Potential of Western Cape Municipalities

This paper provides a brief overview of the relevant post-2000 South African policy for regional (provincial) spatial development within the context of the quantitative findings of a study conducted on the growth potential of non-metropolitan settlements in the Western Cape. The findings are presented at municipal level. Five indices (social needs, economic, physical environment, infrastructure and institutional) and 69 indicators were used to determine development potential and social needs for the 24 local municipalities and three district management areas in the province. The potential indicators for each index were subjected to a factor analysis to select appropriate core indicators for inclusion in the composite indices. Based on their overall performance in the various indices, the municipalities were classified into three categories-high, medium and low. The study results prioritise areas according to their developmental potential and social needs at municipal level. © 2012 Springer Science+Business Media B.V

Hippocampal neurogenesis in the C57BL/6J mice at early adulthood following prenatal alcohol exposure

We examined the effect of chronic prenatal alcohol exposure (PAE) on the process of adult neurogenesis in C57BL/6J mice at early adulthood (PND 56). Pregnant mice, and their in utero litters, were exposed to alcohol, through oral gavage, on gestational days 7–16, with recorded blood alcohol concentrations averaging 184 mg/dL (CA group). Two control groups, sucrose (CAc) and non-treated (NTc) control groups were also examined. The brains of pups at PND 56 from each experimental group were sectioned in a sagittal plane, and stained for Nissl substance with cresyl violet, and immunostained for Ki-67 which labels proliferative cells and doublecortin (DCX) for immature neurons. Morphologically, the neurogenic pattern was identical in all three groups studied. Populations of Ki-67 immunopositive cells in the dentate gyrus were not statistically significantly different between the experimental groups and there were no differences between the sexes. Thus, the PAE in this study does not appear to have a strong effect on the proliferative process in the adult hippocampus. In contrast, the numbers of immature neurons, labeled with DCX, was statistically significantly lower in the prenatal alcohol exposed mice compared with the two control groups. Alcohol significantly lowered the number of DCX hippocampal cells in the male mice, but not in the female mice. This indicates that the PAE appears to lower the rate of conversion of proliferative cells to immature neurons and this effect of alcohol is sexually dimorphic. This lowered number of immature neurons in the hippocampus appears to mirror hippocampal dysfunctions observed in FASD children

Organization of the sleep‐related neural systems in the brain of the river hippopotamus (Hippopotamus amphibius): A most unusual cetartiodactyl species

This study provides the first systematic analysis of the nuclear organization of the neural systems related to sleep and wake in the basal forebrain, diencephalon, midbrain, and pons of the river hippopotamus, one of the closest extant terrestrial relatives of the cetaceans. All nuclei involved in sleep regulation and control found in other mammals, including cetaceans, were present in the river hippopotamus, with no specific nuclei being absent, but novel features of the cholinergic system, including novel nuclei, were present. This qualitative similarity relates to the cholinergic, noradrenergic, serotonergic, and orexinergic systems and is extended to the γ-aminobutyric acid (GABA)ergic elements of these nuclei. Quantitative analysis reveals that the numbers of pontine cholinergic (259,578) and noradrenergic (127,752) neurons, and hypothalamic orexinergic neurons (68,398) are markedly higher than in other large-brained mammals. These features, along with novel cholinergic nuclei in the intralaminar nuclei of the dorsal thalamus and the ventral tegmental area of the midbrain, as well as a major expansion of the hypothalamic cholinergic nuclei and a large laterodorsal tegmental nucleus of the pons that has both parvocellular and magnocellular cholinergic neurons, indicates an unusual sleep phenomenology for the hippopotamus. Our observations indicate that the hippopotamus is likely to be a bihemispheric sleeper that expresses REM sleep. The novel features of the cholinergic system suggest the presence of an undescribed sleep state in the hippopotamus, as well as the possibility that this animal could, more rapidly than other mammals, switch cortical electroencephalographic activity from one state to another. J. Comp. Neurol. 524:2036-2058, 2016. © 2016 Wiley Periodicals, Inc

Microbats appear to have adult hippocampal neurogenesis, but post-capture stress causes a rapid decline in the number of neurons expressing doublecortin

A previous study investigating potential adult hippocampal neurogenesis in microchiropteran bats failed to reveal a strong presence of this neural trait. As microchiropterans have a high field metabolic rate and a small body mass, it is possible that capture/handling stress may lead to a decrease in the detectable presence of adult hippocampal neurogenesis. Here we looked for evidence of adult hippocampal neurogenesis using immunohistochemical techniques for the endogenous marker doublecortin (DCX) in 10 species of microchiropterans euthanized and perfusion fixed at specific time points following capture. Our results reveal that when euthanized and perfused within 15 min of capture, abundant putative adult hippocampal neurogenesis could be detected using DCX immunohistochemistry. Between 15 and 30 min post-capture, the detectable levels of DCX dropped dramatically and after 30 min post-capture, immunohistochemistry for DCX could not reveal any significant evidence of putative adult hippocampal neurogenesis. Thus, as with all other mammals studied to date apart from cetaceans, bats, including both microchiropterans and megachiropterans, appear to exhibit substantial levels of adult hippocampal neurogenesis. The present study underscores the concept that, as with laboratory experiments, studies conducted on wild-caught animals need to be cognizant of the fact that acute stress (capture/handling) may induce major changes in the appearance of specific neural traits