Research Articles (Anatomy)

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Streptozotocin-induced morphological changes in rat lungs
(Taylor and Francis, 2024) Masetla, Felicia Maite; Van Rooy, Mia-Jeanne; Serem, June Cheptoo; Oberholzer, Hester Magdalena; nanette.oberholzer@up.ac.za
Streptozotocin (STZ) is a commonly used compound for the induction of type 2 diabetes (T2D) in animal models, but its effects on non-pancreatic tissues like the lungs are not well understood. This study aimed to examine the histopathological impact of STZ on the lungs using male Sprague-Dawley rats. The rats were divided into two groups: a control group on a normal diet and an STZ-treated group receiving a high-fat diet and 10% sucrose water for 8 weeks, followed by an STZ injection (30 mg/kg body weight). All rats were terminated 9 days after STZ administration, and lung samples were collected for light microscopy, transmission electron microscopy (TEM), and confocal laser scanning microscopy. Light microscopy revealed thickening of alveolar septa, narrowing of alveoli, and inflammatory infiltrates in the STZ group. TEM showed mitochondrial damage in type 2 pneumocytes, including membrane fragmentation, cristae loss, and formation of mitochondrial-derived vesicles. Confocal microscopy revealed significantly higher expression of myeloperoxidase, neutrophil elastase, and citrullinated histone 3 in the STZ group compared to controls. These findings suggest that STZ induces considerable lung damage, emphasizing the need to consider lung toxicity in studies involving STZ.
The in vitro antioxidant and antiadipogenic properties of pigmented flower extracts of Geraniaceae and Lamiaceae plant families
(Wiley, 2025-01) Venter, Anton; Fisher, Hennie; Stafford, Gary I.; Serem, June Cheptoo; Bester, Megan Jean; Duodu, Kwaku Gyebi
This study investigated the potential health-promoting properties of new sources of natural food colorants, namely pigmented flower extracts from Geraniaceae (Pelargonium grandiflorum, Pelargonium × hortorum, Pelargonium zonale hybrid) and Lamiaceae (Salvia aurea × dolomitica, Salvia dolomitica and Plectranthus zuluensis). In the Geraniaceae family, the main phenolic acids identified were hydrolysable tannins, while the main flavonoids were rutinosides of kaempferol and quercetin. In the Lamiaceae family, the main phenolic acids were caffeic acid and its derivatives, and the main flavonoids were naringin and neohesperidin. The total polyphenol content (TPC) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were higher for Geraniaceae than for Lamiaceae species. For all extracts, oxygen radical absorption capacity (ORAC) was similar, except for P. zonale hybrid. These extracts protected Caco-2 cells against 2, 2′-azobis (2-amidinopropane) dihydrochloride (AAPH) generated oxidative damage. Similarly, all extracts, except P. zonale hybrid, effectively scavenged nitric oxide (NO) and reduced lipopolysaccharide (LPS)-induced NO formation in RAW 264.7 macrophages. Inhibition of the formation of advanced glycation end-products (AGE) was significant for P. grandiflorum and P. × hortorum. All pigmented flower extracts, except the P. zonale hybrid, reduced lipid accumulation in differentiated 3T3-L1 adipocytes. Treatment during adipocyte differentiation caused cell death, except for the P. zonale hybrid. In conclusion, related to antioxidant activity, inhibition of AGE formation and lipid accumulation in differentiated adipocytes, P. grandiflorum was the most active, while the P. zonale hybrid was the least. These differences are potentially related to the concentration, type and stability of the polyphenols found in these pigmented flower extracts. Overall, the pigmented flower extracts of Geraniaceae and Lamiaceae show a range of health-promoting properties that represent an additional benefit to their potential use as natural food colourants.
Enhanced gram-negative membrane disruption and in vivo efficacy via lysine-arginine enrichment of Opis16a
(American Chemical Society, 2025-05) Van der Walt, Mandelie; Oosthuizen, Carel B.; Serian, Miruna; Lorenz, Christian D.; Mason, A. James; Bester, Megan Jean; Gaspar, Anabella Regina Marques; anabella.gaspar@up.ac.za
Infections complicate burn wound care, especially with the rise of antimicrobial resistance. Antimicrobial peptides (AMPs) offer the potential for advancing wound care by combating persistent infections. Opis16a, a scorpion venom-derived AMP, exhibits potent antibacterial activity by targeting Gram-negative membranes, causing rapid membrane disruption and bacterial cell death. Here, four novel Opis16a analogues were developed with improved membrane targeting and antibacterial efficacy. One analogue shows particular promise for topical application in Gram-negative burn wound infections. Enhanced peptide–lipid hydrogen bonding increases conformational stability, membrane insertion, and permeabilization rates. Substituting lysine residues in the C-terminal with arginine leads to the most consistent improvement in activity, selectivity for pathogen over HaCat cells, and stability in serum. In an in vivo Galleria mellonella burn wound model, a 5 mg/kg topical dose provides better protection than Opis16a against Enterobacter cloacae NICD 16103. These findings highlight the potential of optimized bactericidal AMPs to improve burn wound care.
The semispinalis capitis muscle skull attachment as a superficial external landmark for the location of the transverse dural venous sinuses
(Elsevier, 2024-11) Prigge, Lane; Hoffman, Jakobus W.; Bam, Lunga C.; Venter, Gerda; lane.prigge@up.ac.za
INTRODUCTION : Identifiable superficial external landmarks can be used to determine the exact location of the internally located dural venous sinuses, for neurosurgical procedures. Several studies have been conducted to determine a standard method or a consistent reliable landmark, but all reported variations and inconsistencies with the examined landmarks. This study evaluated the relationship between the attachment site of the semispinalis capitis muscles on the external aspect of the skull and the internally located transverse dural venous sinuses. METHODS : Fifty-one South African skulls were used in this study. The Micro-focus X-ray Radiography and Tomography (MIXRAD) system at Necsa (Nuclear Energy Corporation South Africa) was used to scan and create three-dimensional images of each skull specimen. Pre-determined reference points were placed on the reconstructed images with the VGStudio Max volume rendering software. The relevant distances and locations of the reference points were measured and documented. RESULTS : The muscle attachment site was located inferior to the transverse sinuses in all the skulls with a mean distance of 15.99 mm (left side) and 19.43 mm (right side). A statistically significant difference was found between all the measurements comparing the left- and right sides, however, no such difference was found between males and females. CONCLUSION : The apical attachment of the semispinalis capitis muscle is a good indicator for the internally located transverse dural venous sinus. This study indicates that a point of entry 8–10 mm inferior to this muscle attachment site be used, for safe access to the internal aspect of the posterior cranium.
Exposure of the facial nerve within the facial canal
(Elsevier, 2024-11) Govender, Shavana; Hanekom, Tania; Human-Baron, Rene; tania.hanekom@up.ac.za
BACKGROUND : The facial canal lies in the petrous part of the temporal bone and contains the facial nerve. The facial canal and nerve are divided into three segments: the labyrinthine, tympanic and mastoid segments, which travel in different planes. These segments are closely related to the structures of the middle- and inner-ear, so pathology of the intracranial facial nerve is often evident in cochlear implant users. The facial canal and nerve are of great concern to otologists during electrode placement for a cochlear implant, as any damage to the nerve may result in untreatable facial paralysis. Few studies have been conducted on a cadaveric population, with most carried out on CT images of the cochlea and facial nerve. Thus, there is no standard or straightforward methodology to visualise the facial canal and nerve directly. We propose a detailed dissection technique to bridge this gap in research. METHOD : Four cadavers were used, and both the left and right facial canals were dissected. After the exposure of the cranial floor, the internal acoustic meatus and the facial canal were dissected out using drilling tools to remove the surrounding temporal bone and expose the facial nerve within the facial canal. RESULTS : This technique allowed for morphometric analyses and observations of the facial canal in relation to the middle- and inner-ear. CONCLUSION : Knowledge of the facial canal may assist otosurgeons in safely dissecting the region without injuring vital structures within this area.
The classification of sacral foramina in a South African sample using cadaveric and osteological remains
(Elsevier, 2024-11) Van Schalkwyk, Jerolize; Matshidza, S.; Mogale, Nkhensani; nkhensani.mogale@up.ac.za
Sacroiliac (SI) joint fixation is a technique used for SI joint fractures, SI joint dislocations and sacral fractures. Sacral screws can be placed either into the S1 or the S2 vertebrae if S1 is insufficient. Malpositioning of the screws is a common surgical complication as sacral variations exists amongst populations. Complications associated with the misposition of screws can lead to injury of the sacral venous plexus, iliac vessels, or sacral nerve roots. Therefore, this study aimed to evaluate sacral variations in a South African sample by determining distances between the first and second sacral foramina and classifying the common types of sacra found. A quantitative cross-sectional comparative study was conducted. One hundred and twenty (n = 120) dry human sacra and 11 formalin-fixed cadavers were measured to determine the linear distances between the first two anterior and posterior sacral foramina. Additionally, the dry human sacra were classified according to Mahato's classification system. A cadaver SI joint fixation simulation was performed by an orthopaedic surgeon. The mean sacral promontory height was found to be 31.81 mm and 37.52 mm in osteological and cadaver specimens, respectively. The mean anterior pedicle height was significantly different for the left (18.81 mm) and right (21.67 mm) side measurements. A statistically significant difference was found between cadavers and osteological samples for all measurements taken. In the osteological sample, ancestry and age mostly influenced the variations noted. Using Mahato's classification system, sacra with five sacral segments, auricular surfaces extending from the superior part of S1 to the middle of S3 and no accessory L5/S1 articulations had the highest prevalence of 59.17 %. The South African sample exhibited similarities but did not fully compare to other populations. The results in this study should be considered as a reference for surgeries involving the SI joint and sacral foramina. However, where possible, the exact anatomy with possible variations of the patient should be evaluated preoperatively using X-rays and angiograms. HIGHLIGHTS • Sacra with five segments and no accessory L5/S1 articulations were noted as 59.17 %.
A retrospective radiologic analysis of the treatment outcomes of ameloblastomas
(Wiley, 2025-05) Smit, Chane; Robinson, Liam; Fonseca, Felipe Paiva; Van Heerden, Willem Francois Petrus; Uys, Andre; chane.smit@up.ac.za
INTRODUCTION : The current study reviewed the postoperative radiologic findings of 156 cases of ameloblastoma diagnosed at a tertiary institution in South Africa. METHODS : Histologically diagnosed cases of ameloblastomas between 2012 and 2022 were retrospectively reviewed. Only cases with both pre- and postoperative radiographs of diagnostic quality were included in the study. The demographics, treatment and follow-up radiologic findings, including recurrences, were assessed. This clinical data was collected from all available patient records and histopathologic reports. RESULTS : Seventy-nine cases of ameloblastoma (50.97%) diagnosed at the institution had post-treatment radiographs available and were included in the study for further analysis. Conservative treatment, including marsupialisation and/or enucleation, was performed in 11 cases (13.92%). The recurrence rate for conservatively treated cases was 44.4% after a mean follow-up of 31.4 months. Tumour resection was performed in 72 cases (91.1%), including 4 recurrent cases previously treated conservatively. Tumour recurrence was only noted in 4 cases (7.5%) treated via surgical resection after a mean follow-up of 25 months. Spontaneous bone regeneration was seen in 19 cases (35.8%) of ameloblastomas treated via surgical resection. CONCLUSION : Ameloblastomas are benign neoplasms with high recurrence rates, emphasising the need for appropriate treatment and extended follow-up periods. The high recurrence rate reported in cases of ameloblastoma managed conservatively highlighted its inappropriate use in treating conventional subtypes. The presence of bony regeneration in this study was higher than the reported literature, correlating with the overall younger age of the current sample.
Anatomical variations of the lateral collateral ligament of the ankle: Implications of sex and laterality on morphology and morphometry
(Elsevier, 2025-06) Hlengwa, Ndumiso Siphelele; Aladeyelu, Okikioluwa Stephen; Mafuika, Seke Nzau; Naidu, Livashin; Rennie, Carmen Olivia
INTRODUCTION : A detailed understanding of the anatomical dimensions of the lateral collateral ligament (LCL) is essential in the surgical treatment of ankle joint injuries and ligament rehabilitation. While previous studies have explored the general morphology and morphometry of the LCL, there remains a gap in understanding how these characteristics vary based on sex and laterality. This study aimed to investigate the morphological and morphometric variations of the LCL, focusing on differences between sexes and between right and left ankles. METHOD : Thirty-one ankles from sixteen human cadavers were dissected to investigate the LCL of the ankle. The LCL consists of the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and posterior talofibular ligament (PTFL). Each ligament of the LCL was classified into three types according to the number of bands, i.e., Type I– single band, Type II– double bands (IIa-partially separated & IIb-completely separated), and Type III– triple bands for morphological observation. The length, width, and thickness of these ligaments were measured using a calliper for morphometric analysis and compared among sex and laterality. RESULTS : Type I was the most observed in all three ligaments (ATFL-61.3 %; CFL-87.1 %; PTFL-96.8 %). Significant sex differences were observed, with males having more Type I, while females had more Type II and III (p < 0.05). PTFL was significantly longer (25.31 ± 3.87 mm) and wider (7.05 ± 2.07 mm) in females (p < 0.05). CFL was significantly longer on the right (37.09 ± 4.57 mm; p < 0.05). CONCLUSION : Morphological and morphometric variations significantly exist in the ligaments that make up the LCL in relation to sex and laterality. These identified variations could improve diagnostic accuracy, enhance surgical planning, and inform sex-specific rehabilitation strategies. HIGHLIGHTS • Lateral collateral ligament (LCL) is essential in the surgical treatment of ankle joint injuries. • LCL play a significant role in maintaining ankle stability. • Variations were observed among the ligaments that make up the LCL in relation to sex and laterality. • These identified variations could improve diagnostic accuracy, enhance surgical planning, and inform sex-specific rehabilitation strategies.
Reliability of using CBCT scans to derive the parameters of the facial canal
(Elsevier, 2025-09) Govender, Shavana; Hanekom, Tania; Human-Baron, Rene
PURPOSE : Studies have analysed the facial canal (FC) parameters using dissection or imaging technologies. To date, no studies have analysed the differences between these methods. The purpose of this study was to evaluate the reliability and accuracy of deriving the parameters from the FC on cone-beam computed tomography (CBCT) scans by comparing it to FC morphometric analyses of dissected heads. METHODS : Ten embalmed heads (n = 20) were CBCT scanned and analysed using ImageJ. Next, each FC segment was dissected. Measurements for both methods included the proximal and distal diameters and lengths for each segment, and angles of the first and second genua. RESULTS : The paired t-test indicated significant differences (p < 0.05) between the CBCT and dissected measurements for most FC segments measured. The respective dissection measurements were consistently higher than the CBCT measurements. However, the Bland-Altman plots showed agreement between the two modalities in measuring FC segments. Interobserver error values were 0.963 and 0.950 for the CBCT and dissection groups, respectively, indicating a high repeatability. CONCLUSIONS : Although the current study showed differences between the parameters of the FC derived from CBCT scans and dissected measurements, CBCT scans remain a valuable tool for non-invasive assessments. However, the differences have implications for modelling in that CBCT measurements underestimate the true size for the various segments of the FC. It is worth noting that a potential difference in segment sizes may exist between populations but will have no effect on using CBCT scans as a pre-operative assessment of the FC.
In silico docking and ADMET studies on clinical targets for type 2 diabetes correlated to in vitro inhibition of pancreatic alpha-amylase and alpha-glucosidase by rutin, caffeic acid, p-coumaric acid, and vanillin
(Springer, 2025-03) Mcmillan, Jamie; Bester, Megan Jean; Apostolides, Zeno; u16016760@tuks.co.za
Please read abstract in the article.
Two triterpenoids, ARM-2 and RA-5, from Protorhus longifolia exhibit the potential to modulate lipolysis and lipogenesis in cultured 3T3-L1 adipocytes
(Wiley, 2024-10) Ndlovu, Musawenkosi; Serem, June Cheptoo; Bester, Megan Jean; Apostolides, Zeno; Opoku, Andrew R.; Mosa, Rebamang Anthony
Triterpenoids have been identified as potential novel lipid-lowering drugs for the treatment of hypertriglyceridemia. This study investigated the potential antilipogenic and/or antilipolytic effects of two triterpenoids (ARM-2 and RA-5) isolated from the stem bark of Protorhus longifolia (Benrh.) Engl. Employing a combination of in silico predictions and in vitro assays, the interactions between these triterpenoids and key proteins involved in lipogenesis and lipolysis were investigated. In silico molecular docking analysis predicted a favourable binding affinity of both triterpenoids to PPARγ, SREBP-1, and AMPK, with lower binding affinity to C/EBPα, pancreatic lipase, and hormone-sensitive lipase (HSL). Both triterpenoids exhibited in vitro inhibition of pancreatic lipase with Ki and IC50 values ranging from 28.7 to 52.9 μM and 27.6 to 35.8 μM, respectively. Total and neutral lipid accumulation in differentiated 3T3-L1 adipocytes and the oleic acid-induced HepG2 cell model was inhibited, with ARM-2 showing better inhibition than RA-5. In the HepG2 model, the inhibitory activity of the two triterpenoids (at 25 and 100 μM) was comparable to 50 μM lovastatin, although the latter was cytotoxic, whereas both ARM-2 and RA-2 lacked cytotoxicity. Associated gene expression was similar to the effect of simvastatin where the expression of SREBP-1, PPARγ, C/EBPα, and HSL was reduced and that of AMPK was unchanged. In vitro studies confirmed that ARM-2 and RA-5 also inhibited adipocyte lipolysis, where the reduction in glycerol release by 25 and 100 μM was similar to 50 μM lovastatin and simvastatin. This study identifies that the triterpenoids, ARM-2 and RA-5, have the potential to modulate lipogenesis and lipolysis.
Quality of life in patients pre- and post-breast reduction surgery in a South African population : a single-centred patient-based study
(Karger Publishers, 2025-06) Khwela, Nokubonga; Madaree, Anil; Mohan, Nivana; Lazarus, Lelika; nivana.mohan@up.ac.za
INTRODUCTION : Breast hypertrophy is the abnormal enlargement of breast tissue resulting in extremely large breasts and is a regular condition among women worldwide. It can affect different aspects of their life, including their psycho-social, sexual, emotional, and physical well-being. This study aimed to assess the quality of life in individuals with breast hypertrophy both before and after undergoing breast reduction surgery. METHODS : Two sets of questionnaires (preoperative and post-operative) were formulated and distributed to 18 patients (median age of 31, age range: 18-48 years) undergoing breast reduction surgery. Patients were also provided with an informed consent form. RESULTS : Preoperatively, most patients expressed different levels of dissatisfaction with themselves across all categories. However, post-operatively, significant levels (p < 0.05, p < 0.001) of satisfaction were demonstrated by patients, as 100% of them reported a reduction in back pain and heaviness of breasts, and 100% reported improvement in their self-confidence. Also, 94% and 65% reported improvement in their social interaction and sexual life, respectively, while 83% and 61% of patients reported satisfaction in carrying their grocery shopping bags and their engagement in regular exercise programs, respectively. CONCLUSION : The study illustrates that breast reduction surgery had a positive effect on the quality of life of patients as a significant proportion of them reported improvement and satisfaction across all categories following the procedure. PLAIN LANGUAGE SUMMARY : In this study, we looked at the quality of life (QoL) of individuals with breast hypertrophy before and after having breast reduction surgery. This study is needed to provide individuals with breast hypertrophy with information about how breast reduction could improve their QoL. It is also necessary to understand patients’ views on breast reduction surgery so that medical health providers can provide appropriate counsel to individuals with breast hypertrophy. The study compared patients’ QoL before their breast reduction surgery to their QoL after the procedure. The study’s findings revealed that individuals with breast hypertrophy saw an improvement in their QoL following breast reduction surgery. It is recommended that people with breast hypertrophy consider breast reduction surgery as a treatment option because it decreases symptoms and improves QoL.
What use are ontogenetic data anyway? Challenges in multivariate modelling of primate tooth formation
(Taylor and Francis, 2025-06) Wolfe, Christopher A.; Boughner, Julia C.; Stull, Kyra Elizabeth
BACKGROUND : The development of the permanent dentition provides a reliable substrate to infer ontogenetic patterns within and among species. Multivariate methods offer a promising approach to compare taxon-specific patterns. AIM : This study used multivariate statistical approaches to compare ontogenetic patterns by more comprehensively quantifying variation in crypt and tooth formation scores for the permanent dentition in five catarrhine primate taxa, Homo sapiens, Pan paniscus, Pan troglodytes, Hylobates lar, and Papio anubis. SUBJECTS AND METHODS : Tooth formation was scored according to published standards for each specimen. Multivariate relationships between teeth were modelled according to a Bayesian multivariate cumulative probit model. Relationships among and between teeth were summarised with correlation matrices, variable loadings plots, and the Frobenius norm. Univariate boxplots were used to contextualise and check the biological salience of the multivariate results. RESULTS : H. sapiens results corroborate previous research and show a degree of modularity that separates early forming and later-forming teeth. All four other species may show broad correlative patterns, but clear biological patterns are masked due to small sample sizes and/or sample composition. CONCLUSION : Even with careful application of statistical procedures, ontogenetic inferences are only as good as the data are comprehensive.
The elastic properties of the tendinous and capsular layers of the rotator cuff complex using fresh tissue-a biomechanical study
(Springer, 2025-02) Cronje, Jessica Y.; Mogale, Nkhensani; Govender, Shavana; De Beer, Mathys A.; Oberholster, Abraham Johannes (Abrie); Mcduling, Chris; Verbeek, Rudi; Nkwenika, Tshifhiwa; Keough, Natalie; Nkhensani.Mogale@up.ac.za
BACKGROUND : Elastic modulus is an important biomechanical component that indicates stiffness or elasticity of biological material. Recently the use of digital image correlation (DIC) in elastic modulus studies on fresh tissue has shown great accuracy in estimating elastic properties; thus, the aim of this study was to investigate the elasticity of capsular and tendinous layers of the rotator cuff complex employing this method. MATERIALS AND METHODS : The supraspinatus, infraspinatus, and subscapularis from eight (n = 8) fresh/frozen tissue shoulders were reverse dissected from their origins. The muscles were separated from one another and dissected to produce 20 × 20 mm tendinous and capsular strips for each muscle. DIC was employed to measure the strain of the tendinous and capsular portions of each of the muscles during tensile testing, and tangent elastic modulus values were obtained. RESULTS : The tendinous layers for supraspinatus, infraspinatus, and subscapularis yielded higher average tangent elastic moduli readings (62.1 MPa, 67.1 MPa, and 59.6 MPa, respectively) compared to their capsular counterparts (29.0 MPa, 32.5 MPa, and 41.5 MPa, respectively). CONCLUSION : Different elastic moduli findings for the tendinous and capsular layers suggest these layers should be considered independently during surgical repair to avoid biomechanical imbalance which may result if these layers were to be repaired as one singular layer.
The influence of rehydration on decomposition in the Highveld region of South Africa—using a pig model
(Wiley, 2024-07) Du Toit, Claire Lynne; Myburgh, Jolandie; Brits, Desire
Researchers have observed that rainfall may re-initiate decomposition in desiccated tissue; however, no conclusive research-based evidence exists on the specific effects of rehydration on decomposition. Therefore, this study aimed to assess the effects of artificial rehydration on the progression of decomposition following the advanced stage of decomposition. Twelve adult pig cadavers (8 experimental; 4 controls) were placed in the central Highveld of South Africa during cooler (April–July 2021) and warmer (August–November 2021) months. Decomposition was scored approximately biweekly to obtain the total body score, and accumulated degree days (ADD) were calculated for each pig. All pig cadavers were covered by chicken wire cages with transparent tarps to control for natural rehydration and scavenging. Once the experimental pig cadavers reached a three-visit stasis in the advanced phase of decomposition, they were artificially rehydrated, and changes in the progression of decomposition between the control and experimental groups were plotted (ADD against TBS) for observation. The rehydrated experimental pig cadavers showed re-initiation of decay and insect re-colonization, while the control cadavers mainly remained in a state of stasis with insect activity ceased altogether. Greater cadaver decomposition islands and a color change post-rehydration were also noted in some experimental cadavers. This supports the need for future research on the impact of rehydration, including associated soil moisture on decomposition rates, progression, and invertebrate colonization, which will enhance our understanding of the effects these environmental factors have on the accuracy of post-mortem interval estimation.
Divergent otolithic systems in the inner ear of Paranthropus robustus and Australopithecus africanus
(Elsevier, 2025-02) Smith, Christopher M.; Hammond, Ashley S.; Urciuoli, Alessandro; Braga, Jose; Beaudet, Amelie; Cazenave, Marine; Laitman, Jeffrey T.; Almecija, Sergio
The bony labyrinth of the inner ear houses the sensory end-organs responsible for balance (otolithic system in the utricle and saccule, and semicircular canal system) and hearing (cochlea). Study of the bony labyrinth has revealed considerable morphological diversity in the hominin lineage (semicircular canals and cochleae) and aided in reconstructing essential aspects of primate evolution, including positional behavior, audition, and phylogenic affinities. However, evidence of evolutionary change in the hominin otolithic system remains elusive. Such morphological variation in these gravitoinertial sensory end-organs may suggest functional differences as their geometry is linked with positional behavior. We approach the question of evolutionary morphological change in the hominin otolithic system by examining bony vestibule morphology in two South African hominin taxa Paranthropus robustus (n = 9) and Australopithecus africanus (n = 6), compared to extant hominids (Pongo pygmaeus, Gorilla gorilla, Pan troglodytes, and Homo sapiens). We use landmark-based shape analyses of 78 extant hominid inner ears by means of virtual three-dimensional models derived from micro-CT scans. Thirty bony landmarks were chosen to approximate otolithic organ morphology and relative configuration. Results show a distinctive morphology in P. robustus compared to A. africanus and extant hominids. Specifically, P. robustus exhibits anterolateral–posteromedial compression in bony otolithic organ structure, reducing the size of the saccule and vestibular aqueduct. In contrast, A. africanus exhibits a modern-human-like otolithic system. This newfound morphological diversity identifies unique bony features of the P. robustus inner ear which 1) offers potential evidence for differential positional behavior between P. robustus and A. africanus and 2) presents osteological markers to be used in taxonomic identification of P. robustus remains and in future assessments of Paranthropus classification.
Exploring mutual and exclusive biological information in cranial metric and morphological variables
(University of Florida Press, 2024-07) Stull, Kyra Elizabeth; New, Briana T.; Corron, Louise K.; Auchter, Leah E.; Spradley, Kate; Wolfe, Christopher A.; Chu, Elaine Y.; Hefner, Joseph T.
Evidence suggests that both craniometric and cranial morphoscopic (MMS) traits elucidate information about cranial phenotypic variation and are appropriate proxies of genetic variation. Yet, the types of variation underlying the expression of craniometric and MMS traits are unknown. Recent data sets of matched skeletal metric and MMS data enable a holistic exploration into the cranial phenotype. Subsequently, the current study strived to provide a better understanding of cranial data used to measure human variation in biological anthropology. Two contemporary U.S. samples were pooled to increase sample size and diversity. Following down-sampling for balanced representation of reported biological males and females, the final sample comprised 310 individuals. Twenty-five interlandmark distances and 11 MMS traits were used in numerous analyses: polychoric correlation, mutual information, mixed factor analysis, and factor analysis of mixed data. No demographic information besides reported biological sex was retained in the analyses. The results consistently indicate that having information about one data type does not provide certainty of another data type, even when the variables are analogous (i.e., nasal breadth and nasal aperture width). Findings reassert that skeletal variables should be analyzed jointly rather than independently to best capture the cranial phenotype. The results also highlight the differential influence of biological variables, such as sexual dimorphism, on the two types of cranial data. As data availability increases and additional matched data-type comparisons can be conducted, we will continue to gain a better understanding of the complexities surrounding skeletal phenotypic variation, evolutionary theory, and population affinity.
A radiologic-pathologic study of the histopathologic variants of ameloblastomas and their proliferation indices
(Elsevier, 2024-09) Smit, Chane; Robinson, Liam; Van Heerden, Marlene B.; Meyer, Pieter Willem Adriaan; Ogunsakin, Ropo Ebenezer; Fonseca, Felipe Paiva; Uys, Andre; Van Heerden, Willem Francois Petrus; chane.smit@up.ac.za
OBJECTIVES: This study aimed to analyze the clinicoradiologic features and Ki-67 proliferation indices between the histopathologic variants of ameloblastomas (ABs) for possible associations. STUDY DESIGN: The diagnosis and histopathologic variant were confirmed for all cases by experienced Oral and Maxillofacial Pathologists. Immunohistochemistry for Ki-67 was performed on the most representative formalin-fixed paraffin-embedded tissue block. Demographic, clinical data and radiologic features were analyzed from patient records and available radiographic examinations. The investigators were blinded to the histopathologic variant and proliferation index when the clinicoradiologic features were assessed. RESULTS: The current study included 116 cases of AB in the final sample. The indolent behavior of the unicystic variant was supported by their low proliferation index and slow growth paired with low frequencies of cortical destruction, loss of teeth, root resorption, and encroachment on anatomical structures. In contrast, the comparatively high proliferation index of the plexiform variant correlated with their fast growth and pain. Furthermore, high radiologic frequencies of cortical destruction, loss of teeth, and encroachment of surrounding anatomical structures supported their more aggressive clinical course. CONCLUSION: Statistically significant differences were noted between certain variants and Ki-67, location, borders, locularity, and cortical destruction, providing better insight into their biological behavior.
A morphometric study of posterior tibial slope differences by sex and ethnicity in a South African population
(Springer, 2025-01) Hohmann, Erik; Nel, Adri; Van Zyl, Reinette; Natalie, Natalie; Mogale, Nkhensani
PURPOSE : Posterior tibial slope (PTS) influences knee kinetics and kinematics. The purpose of this study was to investigate morphology and variation within a sample of the black and white male and female population. METHOD : 480 randomly selected lateral knee radiographs were included. The anterior tibial cortex angle (ATC), proximal anatomical tibial axis angle (PTAA) and the posterior tibial cortex angle (PTC) were measured using ImageJ 1.53e software. Between group differences (black male and females, white males and females) were analysed using one-way ANOVA. RESULTS : Significant differences between the three different angles (p = 0.0001, F = 50.68) but no between group differences for the individual angle measurements (ATC, PTAA, PTC) between ethnicity and sex. For ATC, the angles between groups ranged from 14.20 + 2.81 degrees (Females Black), 14.62 + 3.6 degrees (Male Black), 15.18 + 3.68 degrees (Male White) to 15.54 + 3.21 degrees (Females White). For PTAA, the angles between groups ranged from 10.37 + 2.59 degrees (Females Black), 10.61 + 3.27 degrees (Male Black), 10.68 + 3.27 degrees (Male White) to 10.83 + 3.27 degrees (Females White). For PTC, the angles between groups ranged from 6.07 + 3.13 degrees (Females White), 6.13 + 3.7 degrees (Male White), 6.35 + 2.67 degrees (Females Black) to 6.62 + 3.16 degrees (Male Black). CONCLUSION : This study could not establish differences in posterior tibial slope angles between males and females and ethnicity. Significant differences between ATC, PTAA and PTC angles were observed and PTC angles were smaller when compared to PTAA and ATC angles. The ATC angles ranged between 13.18 and 16.57 degrees, the PTAA angles ranged 9.38–11.87 degrees and the PTC angles ranged between 5.03 and 7.62 degrees for all groups.
Radiologic specific growth rate of ameloblastomas : a clinicopathological correlation
(Wiley, 2025-01) Smit, Chane; Robinson, Liam; Van Heerden, Marlene B.; Meyer, Pieter Willem Adriaan; Fonseca, Felipe Paiva; Van Heerden, Willem Francois Petrus; Uys, Andre; chane.smit@up.ac.za
BACKGROUND : The study aimed to assess the radiologic-specific growth rate of ameloblastomas, evaluating potential associations with demographics, radiologic features, histopathologic variants and proliferation indices. The results of this study will hopefully establish if any clinical or histopathologic features can elude fast-growing ameloblastomas. METHODS : Patients presenting with multiple radiographs before surgical intervention due to various healthcare constraints or patient factors were included in the study. The measurements from each radiograph included the lesion's length, height, width and amount of expansion in these dimensions. Furthermore, the circumference of the lesion was measured in sagittal, coronal and axial planes. The radiologic-specific growth rate was assessed by calculating the difference in measurements from the initial to follow-up radiographs divided by the duration between the visits to calculate the growth rate per year. RESULTS : The specific growth rate was analysed between age groups, histopathologic variants and Ki-67 values, with no statistically significant correlations found in all dimensions measured. A statistically significant faster growth (p = 0.04) was seen in females when measuring the mesial-distal length. When comparing radiologic features, ameloblastomas with loss of border demarcation, severe cortical destruction and tooth displacement demonstrated statistically significant faster growth. CONCLUSION : This study found significant correlations with the growth rate of ameloblastomas, specifically in coronal dimensions, supporting the notion of buccal-lingual growth/expansion for which ameloblastomas are known.

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