Acquisition of cadavers for anatomy education and research in Malawi.

BACKGROUND: The use of human cadaveric dissection forms an essential part of teaching anatomy to health sciences students in Malawi. Despite worldwide struggles in acquiring sufficient human cadavers for anatomy education, the current recommendations on the best anatomy practices require the use of cadavers exclusively from the body donation programs. The current study aims to describe the sources of cadaveric bodies used for anatomy education in the Malawian context and reflect on the feasibility of using cadavers from the body donation program only. METHODS: A retrospective audit of the cadaveric records for the 2006-2022 academic years at the Kamuzu University of Health Sciences was done. The perceived challenges when sourcing the cadavers were identified and described based on the authors experiences in Malawi. RESULTS: The majority (97.3%) of the cadavers used between 2006 and 2022 were unclaimed bodies. The mean age of the cadavers was 45 years. Most (95.6%) of the unclaimed bodies were males. All the unclaimed bodies were sourced from hospitals. The body donation program in Malawi was patronized by populations of European descent only. Strongly held sociocultural and religious beliefs as well as economic reasons were perceived as significant barriers to acquiring cadavers of the indigenous Malawians through the body donation program. CONCLUSION: Cadavers for anatomy education in Malawi are mainly from unclaimed bodies, similar to other African countries. The authors support the transition from using "mostly unclaimed bodies (and, less often, body donation)" to using "mostly body donation (and, less often, unclaimed bodies)" through awareness campaigns that are targeted to address the prevailing challenges.

Bilateral duplicated inferior vena cava associated with aberrant internal iliac and gonadal veins: A case-based narrative review.

BACKGROUND: The left side anterior retroperitoneal approach is preferred for the management of lumbosacral spine disorders as there is reduced risk for vascular injury. The presence of multiple and uncommon venous variations on either side of the spine, like the bilateral duplicated inferior vena cava (DIVC), may complicate surgery in this region. The current study describes two rare cases of bilateral duplicated inferior vena cava associated with internal iliac and gonadal veins. METHODS: The cases were identified during routine human dissections of the posterior abdominal wall of 89 (45 males, 44 females) individuals. The course, relations and morphometry of each duplicated inferior vena cava were examined and recorded. RESULTS: Two (2.2%) of the 89 (1 male, 1 female) dissected individuals showed the presence of bilateral duplicated infrarenal segments of the inferior vena cava. In both cases, the pre-aortic trunk (vein) was the largest and the left inferior vena cava was the smallest. Both cases of bilateral DIVC presented with anomalous interiliac communicating veins, internal iliac veins, and drainage sites of the left gonadal veins. CONCLUSIONS: The duplicated inferior vena cava may present with associated venous anomalies like those related to the gonadal and internal iliac veins. Knowledge of the duplicated inferior vena cava and its associated venous anomalies may be essential for accurately identifying and diagnosing vascular dysfunction and improving radiological interpretation across multiple surgical specialities.

Estimation of sex using dimensions around the metatarsal diaphyseal nutrient foramen: Application of discriminant function analysis and logistic regression models.

Sex estimation equations are population-specific, and a wider use of multiple bones to generate equations will increase the accuracy of sex estimation in forensic settings. The metatarsal bones have been used previously, however the dimensions around the diaphyseal nutrient foramen have not been utilised in sex estimation. The current study aimed to determine the utility of the dimensions around the nutrient foramen of metatarsal bones in estimating sex in the South Africans of European descent (SAED). Five measurements around the nutrient foramen were taken from a total of 876 metatarsal bones (first to fifth) from 186 individual skeletons (99 males, 87 females) obtained from the Raymond A. Dart Modern Skeletal Collection. Measurements subjected to direct and stepwise discriminant function (DFA) and logistic regression (LRA) analyses included total length, distance from proximal end to nutrient foramen, circumference, and mediolateral and dorsoplantar diameters at the level of the nutrient foramen. The original classification accuracies for multivariable functions of the stepwise and direct DFA ranged from 83.1-88.3% to 85.5-88.3%, respectively. The original classification accuracies for multivariable functions of the stepwise and direct LRA ranged from 83.3%-88.7% to 86.2%-88.3%, respectively. The cross-validation classifications showed a drop of 0-2.4% for DFA and 0.2-1.1% for LRA. The width measurements were better predictors of sex than length. The dimensions around the metatarsal bone nutrient foramen exhibit sexual dimorphism in the SAED. The generated DFA and LRA functions produced high average classification accuracies which are useful in sex estimation during forensic human identification.

Topographical anatomy and clinical implications of the metatarsal diaphyseal nutrient foramina across South African populations.

PURPOSE: Metatarsal fractures often occur around the diaphyseal nutrient foramina (NF) which vary in topography depending on population affinity. Topographical and morphometrical knowledge of the NF is crucial in understanding fracture development and fracture site healing patterns. The current study aimed to describe the topography and the morphometry of the metatarsal diaphyseal NF in South African Africans (SAA), South Africans of European descent (SAED) and South Africans of Mixed Ancestry (SAMA). METHODS: The study examined 4284 dry cadaveric metatarsals from both sexes and sides of these populations for NF topography and morphometry, including the presence, number, location, position, size and direction of the NF on the metatarsal bones. RESULTS: The NF was present in 99.4% of the metatarsals. Most (84.5%) metatarsals examined had a single NF. Most (97.4%) NF were located in the middle third of the metatarsal bones. The median foramina index (FI) of the second metatarsal exhibited population affinity and significant differences were found both on the left second metatarsal (P = 0.043), and the right second metatarsal (P = 0.046). The position of NF was predominantly lateral on the first (92.4%), second (64.9%) and third (59.1%) metatarsals, whilst the position was predominantly medial on the fifth (65.1%) metatarsals. The NF positions on the fourth metatarsals showed the greatest population variability. The first metatarsals had primarily dominant-sized and distally directed NF whilst the second through fifth had primarily secondary-sized and proximally directed NF. CONCLUSION: The topographical anatomy of the metatarsal diaphyseal NF appears similar across the South African populations. Metatarsal bones are highly vascularized bones presenting with multiple nutrient foramina.

Topography and Composition of the Iliolumbar Veins in a South African Cohort: Implications for Spinal Surgery.

STUDY DESIGN: A descriptive cross-sectional study of the anatomical variations, morphometry, and histology of the iliolumbar veins (ILVs). PURPOSE: This study aimed to describe the anatomical variations of the ILVs and determine their tissue composition in South African cadavers of European descent. OVERVIEW OF LITERATURE: A safe anterior surgical approach to the L4/L5 intervertebral disc space requires understanding the anatomy of the ILVs. Limited understanding of ILVs and their variations may lead to inadvertent avulsion of veins with subsequent hemorrhage and damage to the adjacent nerves intraoperatively. Variations in ILVs are population specific, but such reports are limited in the South African population. METHODS: Eighty-nine adult cadavers were dissected to reveal ILV patterns. The variations (origin, course, and drainage pattern), morphometries, and topography of the ILVs were studied. A total of 19 (10 proximal, nine distal) ILVs were processed for hematoxylin and eosin, Masson's trichrome, and Verhoeff's histological staining to determine the tissue composition. RESULTS: The ILVs were identified in 100% of the cases, and 45% of the ILVs were anastomosed to each other bilaterally. The rightside ILVs terminated into the posterior surfaces of the iliac vessels (p =0.001), whereas the left-side ILVs terminated into the lateral surfaces (p =0.001). The left-side proximal ILVs had higher elastic fiber composition (p =0.030). The ratio of the ILVs' elastic fibers to collagen fibers was 1:9, and 61% of the cadavers exhibited type 1 ILV pattern. Moreover, 42% of the ILVs were at the S1 vertebral level with 31% lying between L4 and L5 spinal nerve roots. The obturator nerve coursed anteriorly to the ILVs in 96% of cases. CONCLUSIONS: The ILV variations described for South Africans present new additional patterns, such as bilateral anastomosis and laterality of the terminal drainage. The ILVs have more collagen fibers than elastic fibers, predisposing them to avulsion during surgical retraction. The identification of all the ILVs is crucial to minimize inadvertent hemorrhage and damage to adjacent structures.

Forensic Facial Comparison: Current Status, Limitations, and Future Directions.

Global escalation of crime has necessitated the use of digital imagery to aid the identification of perpetrators. Forensic facial comparison (FFC) is increasingly employed, often relying on poor-quality images. In the absence of standardized criteria, especially in terms of video recordings, verification of the methodology is needed. This paper addresses aspects of FFC, discussing relevant terminology, investigating the validity and reliability of the FISWG morphological feature list using a new South African database, and advising on standards for CCTV equipment. Suboptimal conditions, including poor resolution, unfavorable angle of incidence, color, and lighting, affected the accuracy of FFC. Morphological analysis of photographs, standard CCTV, and eye-level CCTV showed improved performance in a strict iteration analysis, but not when using analogue CCTV images. Therefore, both strict and lenient iterations should be conducted, but FFC must be abandoned when a strict iteration performs worse than a lenient one. This threshold ought to be applied to the specific CCTV equipment to determine its utility. Chance-corrected accuracy was the most representative measure of accuracy, as opposed to the commonly used hit rate. While the use of automated systems is increasing, trained human observer-based morphological analysis, using the FISWG feature list and an Analysis, Comparison, Evaluation, and Verification (ACE-V) approach, should be the primary method of facial comparison.

Sleep in two free-roaming blue wildebeest (Connochaetes taurinus), with observations on the agreement of polysomnographic and actigraphic techniques.

Most studies examining sleep in mammals are done under controlled conditions in laboratory/zoological facilities with few studies being conducted in their natural environment. It is not always possible to record sleep polysomnographically (PSG) from animals in their natural environments, as PSG is invasive, requiring the surgical implantation of electrodes on the surface of the brain. In contrast, actigraphy (ACT) has been shown to be a minimally-invasive method to objectively measure overall sleep times in some mammals, although not revealing specific sleep states. The aim of this study is two-fold, first, to measure sleep polysomnographically in free-roaming blue wildebeest (Connochaetes taurinus) under the most natural conditions possible, and second, to establish the degree of concordance between ACT and PSG recordings undertaken simultaneously in the same individuals. Here we examined sleep in the blue wildebeest, in a naturalistic setting, using both polysomnography (PSG) and actigraphy (ACT). PSG showed that total sleep time (TST) in the blue wildebeest for a 24-h period was 4.53 h (±0.12 h), 4.26 h (±0.11 h) spent in slow wave (non-REM) sleep and 0.28 h (±0.01 h) spent in rapid eye movement (REM) sleep, with 19.47 h (±0.12 h) spent in Wake. ACT showed that the blue wildebeest spent 19.23 h (±0.18 h) Active and 4.77 h (±0.18 h) Inactive. For both animals studied, a fair agreement between the two techniques for sleep scoring was observed, with approximately 45% of corresponding epochs analyzed being scored as both sleep (using PSG) and inactive (using ACT).

Development of the Wits Face Database: an African database of high-resolution facial photographs and multimodal closed-circuit television (CCTV) recordings.

Forensic facial comparison is a commonly used, yet under-evaluated method employed in medicolegal contexts across the world. Testing the accuracy and reliability of facial comparisons requires large scale controlled and matching facial image databases. Databases that contain images of individuals on closed-circuit television (CCTV), with matching formal and informal photographs are needed for this type of research. Although many databases are available, the majority if not all are developed in order to improve facial recognition and face detection algorithms through machine learning, with very limited if any measure of standardisation. This paper aims to review the available databases and describe the development of a high resolution, standardised facial photograph and CCTV recording database of male Africans. The database is composed of a total of 6220 standardised and uncontrolled suboptimal facial photographs of 622 matching individuals in five different views, as well as corresponding CCTV footage of 334 individuals recorded under different realistic conditions. A detailed description of the composition and acquisition process of the database as well as its subdivisions and possible uses are provided. The challenges and limitations of developing this database are also highlighted, particularly with regard to obtaining CCTV video recordings and ethics for a database of faces. The application process to access the database is also briefly described.

Construction and reconstruction of brain circuits: normal and pathological axon guidance.

Perception of our environment entirely depends on the close interaction between the central and peripheral nervous system. In order to communicate each other, both systems must develop in parallel and in coordination. During development, axonal projections from the CNS as well as the PNS must extend over large distances to reach their appropriate target cells. To do so, they read and follow a series of axon guidance molecules. Interestingly, while these molecules play critical roles in guiding developing axons, they have also been shown to be critical in other major neurodevelopmental processes, such as the migration of cortical progenitors. Currently, a major hurdle for brain repair after injury or neurodegeneration is the absence of axonal regeneration in the mammalian CNS. By contrasts, PNS axons can regenerate. Many hypotheses have been put forward to explain this paradox but recent studies suggest that hacking neurodevelopmental mechanisms may be the key to promote CNS regeneration. Here we provide a seminar report written by trainees attending the second Flagship school held in Alpbach, Austria in September 2018 organized by the International Society for Neurochemistry (ISN) together with the Journal of Neurochemistry (JCN). This advanced school has brought together leaders in the fields of neurodevelopment and regeneration in order to discuss major keystones and future challenges in these respective fields.

A Preliminary Description of the Sleep-Related Neural Systems in the Brain of the Blue Wildebeest, Connochaetes taurinus.

The current study provides a detailed qualitative description of the organization of the cholinergic, catecholaminergic, serotonergic, orexinergic, and GABAergic sleep-related systems in the brain of the blue wildebeest (Connocheates taurinus), along with a quantitative analysis of the pontine cholinergic and noradrenergic neurons, and the hypothalamic orexinergic neurons. The aim of this study was to compare the nuclear organization of these systems to other mammalian species and specifically that reported for other Cetartiodactyla. In the brain of the blue wildebeest, from the basal forebrain to the pons, the nuclear organization of the cholinergic, catecholaminergic, serotonergic, and orexinergic systems, for the most part, showed a corresponding nuclear organization to that reported in other mammals and more specifically the Cetartiodactyla. Furthermore, the description and distribution of the GABAergic system, which was examined through immunostaining for the calcium binding proteins calbindin, calretinin, and parvalbumin, was also similar to that seen in other mammals. These findings indicate that sleep in the blue wildebeest is likely to show typically mammalian features in terms of the global brain activity of the generally recognized sleep states of mammals, but Cetartiodactyl-specific features of the orexinergic system may act to lower overall daily total sleep time in relation to similar sized non-Cetartiodactyl mammals. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1977-1997, 2020. © 2019 American Association for Anatomy.

Evidence of the sternalis muscle in two South African cadavers.

The sternalis muscle is an infrequent, non-pathological anatomical variant typically misrepresented in a clinical context. It presents with 3-8% prevalence, according to cadaveric studies. The muscles were identified during routine cadaver prosection at the School of Anatomical Sciences, University of the Witwatersrand. Here, we report two cases of the sternalis muscle in two South African White cadavers. Analysis of the sternalis muscles revealed unilaterally present, distinctly defined muscle masses on the right (case number 1, female) and left (case number 2, male) hemithorax, lateral to the sternum. The muscles occurred with a prevalence of 2.25% within the cadaveric population examined. The prevalence of the sternalis muscle is generally low, especially in the European population. Their presence represents the remnants of the cutaneous muscles in the ventral thorax of lower animals. Clinically, the sternalis muscle may be misinterpreted as a pathological mass or lesion, thus accurate knowledge regarding its variations and prevalence is of importance.

Seasonal variations in sleep of free-ranging Arabian oryx (Oryx leucoryx) under natural hyperarid conditions.

Study Objectives: The Arabian oryx lives under hyperarid conditions in the Arabian Desert and exhibits temporal niche switching of activity patterns at a seasonal level. The objective of the current study was to provide a polysomnographic-based study of sleep in free-roaming Arabian oryx in their natural habitat to determine whether extreme seasonal climate variations resulted in changes in sleep patterns and physiology associated with the seasonal switching of temporal niches. Methods: Electroencephalography, nuchal electromyography, actigraphy, and subcutaneous temperature were recorded in free-roaming Arabian oryx in the Mahazat as-Sayd Protected Area, Kingdom of Saudi Arabia during winter and summer. Results: Total daily sleep time in winter was 6.69 and 3.77 hr in summer. In winter, oryx exhibited nocturnal sleep typical of artiodactyls of around 60 kg body mass. In summer, oryx slept mostly during the day and subcutaneous temperature was seen to rise during sleep, but not as rapidly as the rises observed in ambient air temperature. Rapid eye movement sleep formed a very small percentage of total sleep time, especially so in the summer. Conclusions: The unusual sleep patterns and physiology during summer appear to be related to high ambient air temperatures that affect both intrinsic and extrinsic factors necessary for survival. The Arabian oryx appears to use sleep physiology as an adaptive thermoregulatory mechanism in the hot summer months.

Temporal niche switching in Arabian oryx (Oryx leucoryx): Seasonal plasticity of 24h activity patterns in a large desert mammal.

The Arabian oryx, a moderately large mammal that inhabits a harsh desert environment, has been shown to exhibit seasonal variations in activity and inactivity patterns. Here we analyzed the continuous year-round activity patterns of twelve free-roaming Arabian oryx under natural conditions from two varying desert environments in Saudi Arabia using abdominally implanted activity meters. We simultaneously recorded weather parameters at both sites to determine whether environmental factors are responsible for temporal niche switching as well as the seasonal structuring and timing of this behavioural plasticity. Our results demonstrate that Arabian oryx undergo temporal niche switching of 24h activity patterns at a seasonal level and exhibit distinct nocturnal/crepuscular activity during summer, diurnal activity during winter and intermittent patterns of behaviour during the transitional seasons of autumn and spring. In addition, the oryx exhibited inter- and intra-seasonal variations in the temporal budgeting of 24h activity patterns. Strong relationships with both photoperiod and ambient temperatures were found and in some instances suggested that increasing ambient temperatures are a primary driving force behind seasonal shifts in activity patterns. These adaptive patterns may be dictated by the availability of food and water, which in turn are strongly influenced by seasonal climate variations. Overall, the adaptive responses of free-roaming Arabian oryx in such harsh and non-laboratorial conditions provide a framework for comparing wild populations as well as aiding conservation efforts.

Neurochemical organization and morphology of the sleep related nuclei in the brain of the Arabian oryx, Oryx leucoryx.

The Arabian oryx, Oryx leucoryx, is a member of the superorder Cetartiodactyla and is native to the Arabian Desert. The desert environment can be considered extreme in which to sleep, as the ranges of temperatures experienced are beyond what most mammals encounter. The current study describes the nuclear organization and neuronal morphology of the systems that have been implicated in sleep control in other mammals for the Arabian oryx. The nuclei delineated include those revealed immunohistochemically as belonging to the cholinergic, catecholaminergic, serotonergic and orexinergic systems within the basal forebrain, hypothalamus, midbrain and pons. In addition, we examined the GABAergic neurons and their terminal networks surrounding or within these nuclei. The majority of the neuronal systems examined followed the typical mammalian organizational plan, but some differences were observed: (1) the neuronal morphology of the cholinergic laterodorsal tegmental (LDT) and pedunculopontine tegmental (PPT) nuclei, as well as the parvocellular subdivision of the orexinergic main cluster, exhibited Cetartiodactyl-specific features; (2) the dorsal division of the catecholaminergic anterior hypothalamic group (A15d), which has not been reported in any member of the Artiodactyla studied to date, was present in the brain of the Arabian oryx; and (3) the catecholaminergic tuberal cell group (A12) was notably more expansive than previously seen in any other mammal. The A12 nucleus has been associated functionally to osmoregulation in other mammals, and thus its expansion could potentially be a species specific feature of the Arabian oryx given their native desert environment and the need for extreme water conservation.

Arabian Oryx (Oryx leucoryx) Respond to Increased Ambient Temperatures with a Seasonal Shift in the Timing of Their Daily Inactivity Patterns.

The Arabian oryx inhabits an environment where summer ambient temperatures can exceed 40 °C for extended periods of time. While the oryx uses a suite of adaptations that aid survival, the effects of this extreme environment on inactivity are unknown. To determine how the oryx manages inactivity seasonally, we measured the daily rhythm of body temperature and used fine-grain actigraphy, in 10 animals, to reveal when the animals were inactive in relation to ambient temperature and photoperiod. We demonstrate that during the cooler winter months, the oryx was inactive during the cooler parts of the 24-h day (predawn hours), showing a nighttime (nocturnal) inactivity pattern. In contrast, in the warmer summer months, the oryx displayed a bimodal inactivity pattern, with major inactivity bouts (those greater than 1 h) occurring equally during both the coolest part of the night (predawn hours) and the warmest part of the day (afternoon hours). Of note, the timing of the daily rhythm of body temperature did not vary seasonally, although the amplitude did change, leading to a seasonal alteration in the phase relationship between inactivity and the body temperature rhythm. Because during periods of inactivity the oryx were presumably asleep for much of the time, we speculate that the daytime shift in inactivity may allow the oryx to take advantage of the thermoregulatory physiology of sleep, which likely occurs when the animal is inactive for more than 1 h, to mitigate environmentally induced increases in body temperature.