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Several tendons can be used as autografts for anterior cruciate ligament reconstruction, and the choice often depends on the surgeons’ preferences. The quadriceps tendon is a commonly used autograft. This study presented, for the first time, the morphometry of the harvestable area of the QT using a simple tracing method. Adult cadavers of South Africans of European Ancestry were carefully dissected to expose the tendon. Then the tendon outline (premarked to enhance visibility) was then traced on a firmly secured wax paper which assumed the curvature of the tendon in situ. The tracing was then scanned (with its inscribed scale bar) and the morphometrics were measured on the digitized images using an imageJ software. The limb length was also measured in order to normalize all the measurements. Despite the observable difference in the surface area of the quadriceps tendon in each individual, there was no significant difference. For the other measurements, there were no side or sex differences except for the straight distal width which is sexually dimorphic. Some paired parameters showed a strong correlation but the correlation between the limb length and other measurements was weak. These data will be useful for pre-operative planning of anterior cruciate ligament reconstruction and will shed more light into the usability of the quadriceps tendon as a graft with respect to healing at the donor site and the return of knee function.

Sex prediction from bone measurements that display sexual dimorphism is one of the most important aspects of forensic anthropology. Some bones like the skull and pelvis display distinct morphological traits that are based on shape. These morphological traits which are sexually dimorphic across different population groups have been shown to provide an acceptably high degree of accuracy in the prediction of sex. A sample of 100 patella of Mixed Ancestry South Africans (MASA) was collected from the Dart collection. Six parameters: maximum height (maxh), maximum breadth (maxw), maximum thickness (maxt), the height of articular facet (haf), lateral articular facet breadth (lafb), and medial articular facet breath (mafb) were used in this study. Stepwise and direct discriminant function analyses were performed for measurements that exhibited significant differences between male and female mean measurements, and the "leave-one-out" approach was used for validation. Moreover, we have used eight classical machine learning techniques along with feature ranking techniques to identify the best feature combinations for sex prediction. A stacking machine learning technique was trained and validated to classify the sex of the subject. Here, we have used the top performing three ML classifiers as base learners and the predictions of these models were used as inputs to different machine learning classifiers as meta learners to make the final decision. The measurements of the patella of South Africans are sexually dimorphic and this observation is consistent with previous studies on the patella of different countries. The range of average accuracies obtained for pooled multivariate discriminant function equations is 81.9-84.2%, while the stacking ML technique provides 90.8% accuracy which compares well with those presented for previous studies in other parts of the world. In conclusion, the models proposed in this study from measurements of the patella of different population groups in South Africa are useful resent with reasonably high average accuracies.

Although the prevalence of substance use disorders (SUDs) is higher among men, women with SUDs in low- and middle-income countries (LMICs) face unique challenges. Poverty and adversity, inequality of women, and disparities in access to treatment and prevention services exacerbate biological, psychological and social correlates of substance use disorders for women living in low-resource settings. Increasing the inclusion of women in research has long been a goal, though even high income countries struggle to achieve parity. In LMICs, women with SUDs are often neglected from global research due to underreporting and the disproportionate focus of global substance use research on men. We will discuss risk factors for SUDs that are particularly relevant for women residing in LMICs in order to gain insight into neglected areas of research and opportunities for prevention and treatment.

Children with Fetal Alcohol Spectrum Disorder (FASD) have impaired sensory processing skills as a result of neurodevelopmental anomalies. The somatosensory barrel field of rodent brain is a readily accessible model for studying the effects of alcohol exposure. Within the barrel field, the posterior medial barrel subfield (PMBSF) receives sensory inputs from the large vibrissae on the contralateral face. This study reports on the consequence of prenatal exposure to alcohol on the somatosensory cortices of mice later in life. Two control groups, a sucrose and a non-treated control, were also examined. At postnatal day (PND) 56 the cerebral hemisphere of mice from each group were processed for cytochrome oxidase reactivity. In contrast to previous studies, there were no significant differences in the mean areas of: (I) the PMBSF enclosure, (II) the PMBSF barrels, (III) the individual PMBSF barrels and (IV) the septal portion of the PMBSF in the alcohol group compared to the controls. However barrel sizes in rows D and E in the alcohol group were significantly reduced, indicating an alcohol-induced damage on the barrel development and which may reduce the amount of the cortex devoted to processing somatosensory input– a common defect seen in children with FASD.

Graphical abstract The dentate gyrus (DG) in rodent hippocampus is a site of neurogenesis. Newly developing neurons can be identified through immunostaining for doublecortin (DCX). We have found that genetic inactivation of the kinase activity of MSK1 (in red) results in an increase in the number of DCX-positive (DCX+) cells. This suggests that MSK1 negatively regulates neurogenesis in the subgranular zone, potentially to limit the number of new neurons in the dentate gyrus and maintain the stability of neuronal networks., Highlights • Neurogenesis in the subgranular zone of the hippocampal dentate gyrus was examined. • Ki-67 staining was not affected by the loss of MSK1 kinase activity. • DCX staining was increased in the MSK1 kinase dead mutant mouse. • MSK1 may negatively regulate neurogenesis to maintain stable neuronal networks., Neurogenesis in the subgranular zone (SGZ) of the adult hippocampus can be stimulated by a variety of means, including via exposure of experimental animals to an enriched environment that provides additional sensory, social, and motor stimulation. Tangible health and cognitive benefits accrue in enriched animals, including the amelioration of signs modelling psychiatric, neurological and neurodegenerative conditions that affect humans, which may in part be due to enhanced production of neurons. A key factor in the neuronal response to enrichment is the release of brain-derived neurotrophic factor (BDNF) and the activation of the Mitogen-Activated Protein Kinase (MAPK) cascade, which can lead to the stimulation of neurogenesis. Mitogen- and Stress-Activated protein Kinase 1 (MSK1) is a nuclear enzyme downstream of BDNF and MAPK that regulates transcription. MSK1 has previously been implicated in both basal and stimulated neurogenesis on the basis of studies with mice lacking MSK1 protein. In the present study, using mice in which only the kinase activity of MSK1 is lacking, we show that the rate of cellular proliferation in the SGZ (Ki-67 staining) is unaffected by the MSK1 kinase-dead (KD) mutation, and no different from controls levels after five weeks of enrichment. However, compared to wild-type mice, the number of doublecortin (DCX)-positive cells was greater in both standard-housed and enriched MSK1 KD mice. These observations suggest that, while MSK1 does not influence the basal rate of proliferation of neuronal precursors, MSK1 negatively regulates the number of cells destined to become neurons, potentially as a homeostatic control on the number of new neurons integrating into the dentate gyrus.

Background: Tendocalcaneus is a strong tendon that is vital for bipedalism in humans. Despite its tremendous strength, the tendocalcaneus is prone to damage and degeneration causing mobility problems and pain. Morphometric dimension of the tendocalcaneus is of benefit to the surgical repair and reconstruction of the damaged tendon. Cadaveric approach provides a realistic method for determining tendocalcaneus morphometry and as at present only two cadaveric studies on Indian population is available. Thus this study presents data on tendocalcaneus morphometry in South Africans of European ancestry using a cadaveric approach. Materials and methods: A total of 66 lower limbs (32 left and 34 right legs) sourced from 49 male and female cadavers were used. After careful dissection of the posterior aspect of leg, the medial and lateral length, distal width, distal circumference and proximal width of the tendocalcaneus were measured. Results: The data showed a high degree of reproducibility indicating that the measurements obtained using cadaveric approach were precise and accurate. There was no difference in measurements between the sides. Measurements in the males were generally higher than in the females. Strong associations were observed between the paired measurements of the medial and lateral tendon length and between the distal width and distal circumference. Conclusions: The data obtained will be useful in predicting tendocalcaneus size during the surgical reconstruction of the tendocalcaneus.

Although the prevalence of substance use disorders (SUDs) is higher among men, women with SUDs in low- and middle-income countries (LMICs) face unique challenges. Poverty and adversity, inequality of women, and disparities in access to treatment and prevention services exacerbate biological, psychological and social correlates of substance use disorders for women living in low-resource settings. Increasing the inclusion of women in research has long been a goal, though even high income countries struggle to achieve parity. In LMICs, women with SUDs are often neglected from global research due to underreporting and the disproportionate focus of global substance use research on men. We will discuss risk factors for SUDs that are particularly relevant for women residing in LMICs in order to gain insight into neglected areas of research and opportunities for prevention and treatment.

This case study describes the morphology and embryology and hypothesizes the muscle action based on the morphology of an anomalous muscle that extends from the long head of the biceps femoris to the medial head of the gastrocnemius muscles. It has an uncommon nerve supply via the medial sural cutaneous nerve which is mainly sensory in humans. This variation is different from other similar variations involving the gastrocnemius and biceps femoris muscles. The case report will be of benefit to diagnosis, clinical training, and surgical procedures as well as contribute to knowledge on the type of nerve fiber carried by the medial sural cutaneous nerve or its components.

We examined the effect of chronic prenatal alcohol exposure on certain neuronal systems involved with the sleep-wake cycle of C57BL/6J mice exposed to prenatal alcohol once they had reached 56 days post-natal. Pregnant mice were exposed to alcohol, through oral gavage, on gestational days 7–16, with recorded blood alcohol concentration (BAC)s averaging 1.84 mg/ml (chronic alcohol group, CA). Two control groups, an oral gavage sucrose control group (chronic alcohol control group, CAc) and a non-treated control group (NTc), were also examined. At 56 days post-natal, the pups from each group were sacrificed and the whole brain sectioned in a coronal plane and immunolabeled for cholineacetyltransferase (ChAT), tyrosine hydroxylase (TH), serotonin (5HT) and orexin-A (OxA) which labels cholinergic, catecholaminergic, serotonergic and orexinergic structures respectively. The overall nuclear organization and neuronal morphology were identical in all three groups studied, and resemble that previously reported for laboratory rodents. Quantification of the estimated numbers of ChAT immunopositive (+) neurons of the pons, the TH+ neurons of the pons and the OxA+ neurons of the hypothalamus showed no statistically significant difference between the three experimental groups. The stereologically estimated areas and volumes of OxA+ neurons in the CA group were statistically significantly larger than the groups not exposed to prenatal alcohol, but the ChAT+ neurons in the CA group were statistically significantly smaller. The density of orexinergic boutons in the anterior cingulate cortex was lower in the CA group than the other groups. No statistically significant difference was found in the area and volume of TH+ neurons between the three experimental groups. These differences are discussed in relation to the sleep disorders recorded in children with fetal alcohol spectrum disorder (FASD).

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.

Morphometric analyses of the patella and patellar ligament have been reported to be important in human identification, in knee implant design and in certain surgical procedures of the knee. It has also been shown that success in the functionality of a knee arthroplasty (knee replacement) is dependent on the implant being of an appropriate dimension. We undertook this study because of the lack of available data on these dimensions in South Africans. Careful dissection was carried out on both knees of 46 South African cadavers (25 females and 21 males) of European ancestry. The quadriceps femoris tendon and patellar ligament were carefully freed from the underlying structures. Eight measurements of the patella and patellar ligament were taken using a Vernier caliper. Patellae were also classified based on the dimensions of the articular facets. No significant difference was found when the measurements taken from both knees were compared except for the dimensions of patella thickness and widths. Dimensions of the patella, patellar ligament and articular facets are sexually dimorphic. In addition, measurements of the patella and patellar ligament showed significant positive correlations, with Type B patellae being the most prevalent in South Africans of European ancestry. The data from the present study will be beneficial in clinical and pathological practices and for local anthropological records.