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Squirrels are diurnal rodents with high visual acuity including unique properties well-suited for their natural environment. This study was conducted to explore some ocular microscopic features of tree-harbouring squirrels in the University of Ibadan, Ibadan, Nigeria. Two male squirrels were cage-trapped within the University premises. Light microscopic analysis was carried on paraffin-embedded eye samples harvested from the animals. The densely compacted stromal fibres, 351 ± 52.5 µm thick, formed the thickest part of the cornea, and the basement membrane of the corneal epithelium, 63.8 ± 13.0 µm thick, was notably positive with Periodic Acid Schiff (PAS) stain. Strong pigmentation was present at the choroid as well as the iridal and ciliary epithelia. The multiple layering of the retinal structure exhibited densely packed ganglion cells at the ganglion cell layer which together with the nerve fibre layer was observed to be thinnest at the more peripheral portion but becomes thicker towards the optic disc. Strongly positive glia fibrillary acidic protein (GFAP+) cells with their abundant fibrous processes were demonstrated immunohistochemically at the retinal nerve fibre layer and the optic nerve. Histological features of the retinal cellular components of the tree squirrels investigated has thus highlighted the structural adaptation of these animal species to their environmental arboreal habitat and diurnal lifestyle. Findings from this study, while further noted to be similar to that in human, showed that African tree squirrels represent promising rodent model for human retinal/ocular research.

The mammalian pineal gland is a structure that in recent years has been extensively studied, due to its functions and the hormones it produces. Bats are the only known flying mammals, with the order having a large number of species. This study was carried out to investigate the gross and histological features of the pineal gland of the Eidolon helvum, the African fruit bat, using male and female subjects. Eight free flying E. helvum (4 males, 4 females) were captured using mist nets. The pineal gland was grossly observed to be very small in size, oval in shape, and covered by the pia mater. Histological examination revealed two populations of pinealocytes – Types I and II – oval structures possessing acidophilic cytoplasm and large, round nuclei. Pinealocytes were seen to appear singly or in clusters, having no particular arrangement. Sexual dimorphism was observed, with the females having less density in population of pinealocytes at the peripheral region of the gland. This was consistent in all subjects examined. Astrocytic appearance was typical with long and slender processes, and perivascular and capsular microglia were observed. The glia cells were observed to be abundant in the parenchyma and around the capsule. There was no sensitivity to NeuN antibody. Results obtained may find application in behavioural and comparative neuroscience.

The structural parts of brain are similar in all vertebrates, but they differ in their complexity and organization. The avian brain for instance, is organised differently compared to mammals, with variations existing in the relative size and location of their structures. The cattle egret (Bubulcus ibis) is a cosmopolitan avian species native to Africa. Despite their economic importance as excellent sentinels in assessing environmental pollutants, there is a dearth of information on their neuroanatomy. Hence, we here investigated their gross morphological features and morphometric parameters, and the cerebellar histology. Twelve transcardi-ally perfused juvenile cattle egrets were studied, with the body and brain weights and brain linear measurements considered. The brain weight constituted 0.46 % of the total body mass, with a strong positive correlation recorded between the body and brain weights (r = 0.9204). Morphologically, the brain was lissencephalic, with the corpus callosum absent and the olfactory bulbs rudimentary with no discernible division into the olfactory bulb, olfactory tract and olfactory lobe. We observed prominent sagittal eminence and vallecula telencephali, as well as an obvious fovea limbica on the dorsal and lateral surfaces of the cerebral hemispheres, respectively. The diencephalic structures were completely covered by telencephalon, with the pineal gland occupying the polygonal space between cerebrum, optic lobe and cerebellum. The mesencephalic tectum appeared as a large oval bilaterally bulging structure with prominent optic tracts and constituted the bulk of the midbrain. There was a dorsal extension of the fourth ventricle into the cerebellum known as the ventriculus cerebelli and the cerebellar histology presented a persistent external granular layering suggestive of a potential for adult neurogenesis. Our data has added relevant literature on the cattle egret brain and could prove useful in comparative, developmental and evolutionary avian neuroanatomy.

The incidence of spinal cord (SC) injury in developed and undeveloped countries is alarming. The pig (Sus scrofa) has been recommended as a suitable research model for translational studies because of its morphophysiological similarities of organ systems with humans. There is a dearth of information on the SC anatomy of the large white and landrace crossbreed (LW‐LC) pigs. We therefore aim to describe the gross morphology and morphometry of its SC. Twelve juvenile LW‐LC pigs (six males and six females) were used. The skin and epaxial muscles were dissected to expose the vertebral column. The SC was carefully harvested by laminectomy, and 13 gross SC morphometric parameters were evaluated. Thirty‐three spinal nerves were seen emanating from either side of the SC by means of dorsal and ventral spinal roots. The overall average of SC length and weight was 36.23 ± 1.01 cm and 16.60 ± 0.58 g, respectively. However, the mean SC length and weight were higher in females compared with males, with SC weight being statistically significant. A positive relationship between SC length and weight was significant for males (p = 0.0435) but not for females (p = 0.42). Likewise, the strength of the relationship between SC length and weight was significant in males (r = 0.82) but not significant in females (r = 0.41). Baseline data for the morphometric features of the spinal cord in the LW‐LC pigs were generated, which will contribute to the knowledge of this species anatomy and useful information on regional anaesthesia that should further strengthen the drive in adopting the pig as a suitable research model for biomedical research. [ABSTRACT FROM AUTHOR]

Anatomists, clinicians and public health experts agree that knowledge of anatomy is vital to safe and efficient clinical practice, and of relevance to meat inspection. With little known about the impact of teaching anatomy to veterinary students; we conducted a pilot study to determine the performance and preference of veterinary students about learning anatomy and their predictors. We administered structured questionnaire to 39 paraclinical and 87 clinical students of the Faculty of Veterinary Medicine, University of Ibadan, Nigeria. Descriptive statistics and test of significance between categorical variables was done using Fisher's exact test at 5% significant level. The study revealed that most students (73.0%) passed all anatomy courses at first sitting and that 87.3% preferred Veterinary Gross-Anatomy to either Micro-anatomy or Embryology. The use of combinations of lecture notes, text-books and audiovisuals was highly significant (OR = 20.2; 95% CI 2.4 - 967.1) to passing anatomy at first sitting. In the logistic regression, variables such as students' impression about learning anatomy (OR = 5.3; 95% CI 1.4 - 19.5); impression about the pattern of teaching Microanatomy (OR = 0.1; 95% CI 0.02 - 0.4) and adequacy of continuous assessment (OR = 4.8; 95% CI 1.4 - 16.6) remained predictors of students' preference for Gross- Anatomy. The use of adequate lecture notes, relevant textbooks and use of audiovisuals in the course delivery is advocated for optimal performance. The learning of anatomy should be driven by an intrinsic interest, allowing students to use learning strategies that are more engaging and cognitive in nature. [ABSTRACT FROM AUTHOR]

The pigs, domesticated about 6000 years ago, are highly prolific omnivores belonging to the Family Suidae and Order artiodactyla along with their other hooved counterparts. They qualify as models for various translational research studies (including dental studies) because of their anatomical and physiological similarities to humans. There is however a dearth of information as regards the deciduous dental eruption profile (sequence and timing of eruption) of the Nigerian local pigs (NLP). This study was designed to determine the deciduous eruption profile in the NLP to assist in the management of the breed and in a bid to making the NLP more obvious as suitable animal models in dental research. A total of 51 healthy piglets (from postnatal day 1) were used for this. Their oral cavities were examined every other day for 29 weeks for signs of dental eruption. Looking at Mandibular (Md) and Maxillary (Mx) eruptions for Incisors (I), Canines (C), Premolars (P) and Molars (M). The modular sequence in the NIP was Md/ Mx I3 (at birth), C (at birth) →Md I1→Md P3→MxP3 →MxI1 → Md I2 →MdP4 →MxP4 →MxP2→ Md I2 →MxI2. It was also observed that variations in eruption timing exist amongst individuals and sexes while variation in eruption sequence exists between NLP and various breeds of pigs based on the literature. The results of this study will be particularly important to farmers, and researchers into NLP especially those using pigs in Nigeria as a model for translation research. [ABSTRACT FROM AUTHOR]

Fluoride is an environmental contaminant that is ubiquitously present in air, water, and soil. It is commonly added in minute quantity to drinking water, toothpaste, and mouth rinses to prevent tooth decay. Epidemiological findings have demonstrated that exposure to fluoride induced neurodevelopmental toxicity, developmental neurotoxicity, and motor disorders. The neuroprotective effect of clofibrate, a peroxisome proliferator‐activated receptor alpha agonist, was investigated in the present study. Forty male Wistar rats were used for this study and randomly grouped into 10 rats per group as control, sodium fluoride (NaF) alone (300 ppm), NaF plus clofibrate (250 mg/kg), and NaF plus lisinopril (10 mg/kg), respectively, for 7 days. NaF was administered in drinking water while clofibrate and lisinopril were administered by oral gavage. Markers of neuronal inflammation and oxidative stress, acetylcholinesterase activity, and neurobehavioral (hanging wire and open field) tests were performed. Immunohistochemistry was performed on brain tissues, and they were probed with glial fibrillary acidic protein, ionized calcium‐binding adaptor molecule 1, and cerebellar Ca2+‐binding protein calbindin‐D28k. The results showed that NaF significantly increased of oxidative stress and neuroinflammation and inhibited AChE activity. Immunostaining showed reactive astrocytes, microgliosis, loss of dendritic spines, and arborization in Purkinje cells in rats administered only NaF. Neurobehavioral results showed that cotreatment of NaF with clofibrate improved muscular strength and locomotion, reduced anxiety, and significantly reduced astrocytic count. Overall, cotreatment of NaF with either clofibrate or lisinopril showed neuroprotective effects by mitigating neuronal inflammation and oxidative and motor incoordination. Hence, clofibrate could be seen as a novel drug candidate against neurodegeneration and motor disorders. [ABSTRACT FROM AUTHOR]

Depletion of myelin and neurobehavioural deficits are indications that vanadium crosses the blood‐brain barrier and such neurotoxic effects of vanadium on the brain of Wistar rats have been elucidated. The effect however on the peripheral nerves, is yet to be reported. Thus, this work was designed to evaluate the axonal and myelin integrity of sciatic nerves in Wistar rats following exposure to vanadium. Ten male Wistar rats were exposed to 3 mg/kg body weight of sodium metavanadate for 7 days, subjected to rearing and forelimb grip behavioural tests, and sciatic nerves processed for histology (haematoxylin and eosin, cresyl violet, and luxol fast blue). Dystrophic axons with vesiculated myelin, thinned myelin sheath, and demyelinated axons were observed in the vanadium exposed rats, suggestive of axonopathy, classified as fourth‐degree nerve injury. Lower behavioural scores were recorded for vanadium‐dosed rats; thus, corroborating histological pictures observed of the sciatic nerves. Authors posit that vanadium crossed the "blood‐nerve" barrier and caused the observed axonal pathologies and myelin depletion in the sciatic nerves of these rodents with resultant motor deficits. The present paper discusses possible motor deficits and the likely public health importance in regions with crude oil pollution and gas flaring rich in vanadium products. [ABSTRACT FROM AUTHOR]

Moringa oleifera is reported to be a miracle plant, with positive effects on practically every system in the animal body. The methanolic extract of Moringa oleifera leaves was fractionated using liquid-liquid fractionation, column chromatography and preparative high-performance liquid chromatography (HPLC). Bioassay guided fractionation using Ferric Reducing Antioxidant Power (FRAP) was used to determine the fraction with the highest antioxidative power. Chemical structure was elucidated with nuclear magnetic resonance (NMR) spectroscopy. FRAP showed that the pure compound, butyl p-hydroxyphenyl-acetate (MIMO2) exhibited an antioxidant activity higher than TEMPOL (positive control). Vanadium is a metal, which as a salt has been shown to be a neurotoxicant; and was therefore used to assess the efficacy of MIMO2 in this experiment. HT22 (immortalized mouse hippocampal) cells were used for cell culture. The Comet assay showed a statistically significant reduction (p < .05) in DNA damage when 0.25 and 0.5 μM MIMO2 as well as 0.1 and 0.2 mg of the methanolic extract of Moringa oleifera leaves (MO) were used in combination with 200 μM vanadium (sodium metavanadate). Analogously, a reduced formation of superoxide was observed using dihydroethidium (2,7-Diamino-10-ethyl-9-phenyl-9,10-dihydrophenanthridine—DHE) stain after 0.5 μM MIMO2 and 0.063 mg MO were used in combination with vanadium 100 μM. MIMO2 and MO gave a statistically significant (p < .05) protective effect against vanadium toxicity on neuronal cells. Further assays may need to be performed to assess the extent of protection that MIMO2 may offer, and also to better understand its mechanisms of action. [ABSTRACT FROM AUTHOR]

Pentavalent vanadium (metavanadate salt) toxicity is a challenging environmental hazard that affects living organisms. Studies have shown that plants play important roles in protecting against heavy metal toxicity. This study was designed to evaluate the protective activity of ethanolic extracts of Grewia carpinifolia leaves following vanadium toxicity. Twenty-five male Swiss mice were randomly divided into five groups (A–E) of five rats each. Group A rats served as control and were given distilled water, Group B was administered with sodium metavanadate and a known antioxidant agent; α-tocopherol, Groups C and D were administered with sodium metavanadate and ethanolic extract of Grewiacarpinifolia leaves orally at 100 and 200 mg/kg body weight respectively while Group E was administered with only sodium metavanadate. After a daily single oral dosing for seven days, changes in behaviour, haematology and serum biochemistry parameters were analysed. Sodium metavanadate caused a significant decrease (p≤0.05) in haematocrit levels, haemoglobin (Hb) concentration, white blood cell count, neutrophil count and serum cholesterol level. A significant (p≤0.05) lymphocytosis was also observed in the group administered with sodium metavanadate alone. G.carpinifolia extract given concomitantly with sodium metavanadate was able to restore PCV, Hb concentrations and serum total protein to levels comparable with the control and standard groups. Grewia carpinifolia also significantly reduced the elevated serum levels of AST and ALT after vanadium induced hepatotoxicity. Our findings suggest that G. carpinifolia extract protected against the toxicity induced by vanadium; the plant extract at 200 mg/kg however appear to offer a better protection. [ABSTRACT FROM AUTHOR]

In this study, the morphological and biochemical susceptibility of the rat brain to vanadium, in the form of sodium metavanadate, and the comparative ameliorative effect of Garcinia kola and kolaviron ( G. kola extract), was examined. Brain regions examined were the cerebrum, cerebellum, hippocampus and the olfactory bulb. We showed that vanadium administration caused cellular vacuolation, congestion, and Purkinje cell degeneration and a marked reduction in myelin tracts. Biochemical tests revealed increased lipid peroxidation induced by vanadium, which was ameliorated with the administration of G. kola and kolaviron. Vanadium administration caused an increase in thiobarbituric acid-reactive substances (TBARS) in the cerebrum and hippocampus, whereas the administration of kolaviron resulted in a reduction of the TBARS level by 65.7 and 80%, respectively, in the regions aforementioned. Also, the administration of kolaviron resulted in an increased activity of superoxide dismutase (61.24%) in all brain regions assessed, when compared with the group administered vanadium alone. Results obtained from this study led to the conclusion that kolaviron reduces vanadium-induced oxidative stress in the brain. [ABSTRACT FROM AUTHOR]

Tooth-wear signatures obtained from maxillary carnassial fourth premolar teeth of raccoons in three ecologic regions in Nigeria testified to segregations in diet of the species with more abrasive diet in specimens from coastal south-western areas compared to more vegetal diet content of those from middle belt and northern areas. Endoloph assessments showed sexually dimorphic mesowear signals between and within locations suggestive that males are more exposed to dental wears compared to females; Male and female specimens from rainforest zone had 40.2% and 34.2% respectively, Sudan Savanna zone had 46.8% and 40.6% for females and males while 67.6% and 44.3% for Sahel zone specimens in similar order. We investigated dietary resource use for sustained survivability within limits of interspecific spatial overlaps using seasonal rainfall indices between two years. There was 86% per high dental occlusal surface relief in the specimens from the savannas while 32% per low relief was observed in South-Western badgers teeth samples. This study observed a change in habitat use as a predisposing factor to sub-regional dental wear differences among age groups as well as sexes of species from three geographic climatic areas. The richness of the eco-habitat/life expectancy found in the rain forest can be ascribed to diet availability which is reduced in the savanna areas. The study suggests minimal change in habitat use as a predisposing factor in sub-regional species dental relief differences observed among age groups and sexes of the species from three geographic climatic areas and also represents quality of the eco-habitats.

The African Giant Rat, AGR is an indigenous nocturnal rodent noted for its unique olfactory and cognitive abilities. They have been deployed more recently in the detection of landmines and diagnosis of tuberculosis - two scourges that have had a tremendous negative impact on the African landscape. This olfactory-aided cognition has been linked to the hippocampus. While the anatomical infrastructure of the olfactory bulb of the AGR has been elucidated, little is known about the adaptive cytoarchitecture of the AGR hippocampal formation. This study describes the histological features, including subfields and stratifications of the AGR hippocampus using Nissl and Golgi stains. The basic cytoarchitecture of the AGR hippocampus observed in this study, with respect to stratification, subfields and cell types, is similar to those reported in the laboratory rats. Cell types identified in the AGR hippocampus include pyramidal cells, granule cells and mossy cells with mossy fibers and Schaffer collaterals also delineated. Hippocampal proper subfields CA1 to CA4 were identified. CA3 pyramidal neurons formed a well-defined cell layer starting in between the upper and lower ends of the dentate gyrus and had larger, more distinct pyramidal cells and higher cell layer thickness (240.0±6.0 µm) relative to subfields CA1 (87.0±2.0 µm) and CA2 (109.0±4.20 µm) with significant statistical differences at p<0.001. The detailed, delicate arrangement of various cell types and subfields, intricate wiring with synapses and laminar organization of the hippocampal formation noticed in the AGR strongly supports the canonical trisynaptic circuitry of the hippocampus. It will however be necessary to carry out densitometric studies and detailed neurochemical profiling of the AGR hippocampus to fully elucidate the functional leverage of this unique rodent. We, therefore, suggest the suitability of this rodent as a model for olfaction-linked memory studies.

The University of Ibadan/Grass Foundation Workshop in Neuroscience Teaching (March 31 st to April 2 nd , 2017) in Ibadan, Nigeria was sponsored by the Grass Foundation as a "proof of principle" outreach program for young neuroscience faculty at Nigerian universities with limited educational and research resources. The workshop's goal was to introduce low cost equipment for student lab exercises and computational tutorials that could enhance the teaching and research capabilities of local neuroscience educators. Participant assessment of the workshop's activities was very positive and suggested that similar workshops for other faculty from institutions with limited resources could have a great impact on the quality of both the undergraduate and faculty experience.