Anatomia, Volume 2, Issue 4 (December 2023) – 7 articles

This article delves into the life and accomplishments of Juan Valverde de Amusco (c. 1525–c. 1587), a Spanish anatomist. Specifically, it focuses on his book titled HISTORIA de la composición del cuerpo humano. The book was the first anatomy opus published after Andreas Vesalius’ De humani corporis fabrica libri septem, written in a Romance language, the Castilian Spanish language, making it the most renowned post-Vesalian anatomy book in Europe and beyond during the 16th and 17th centuries. Compiling complete editions and reproductions of figures, it had 19 editions and several translations. One of its principal contributions was the initial graphical representation of the stapes ossicle. It provided the first accurate description of the pulmonary circulation, vomer bone, and four extraocular rectus muscles. Throughout the book, Valverde corrected numerous of Vesalius’ anatomical observations. HISTORIA de la composición del cuerpo humano was the first anatomy book to use chalcographic illustrations, which are of superior anatomical quality than those printed from engraved wood in Andreas Vesalius’ book. Next, many anatomy textbooks of that time incorporated Valverde’s book illustrations. Valverde’s book was practical, timely, and well referenced, making it a valuable resource for scholars and non-scholars. The conclusion is that Juan Valverde de Amusco merits a place as a pioneer in scientific knowledge transfer. Full article

The primary afferent system in the rat’s spinal cord starts to develop in the third last week of gestation. First, the pseudounipolar DRG neurons extend their centripetal long primary axons, targeting rostral supra-segmental nuclei in the spinal cord. Meanwhile, the subsequent innervation of the juxta- and intra-segmental spinal levels enables the three subdivisions to commence integrating a complex network with the body periphery. This process may continue to refine and adapt the system life-long. The experimental data elucidated the steps involved in developing the cytoarchitecture by separating the axons of the long and intermediate subdivisions from the short subdivision. Here, we present a blueprint of the features of the long primary afferent axons developing in sequential waves. The pioneering long afferent axons targeted the dorsal gracile nuclei at spring tide and Clarke’s nuclei at neap tide in ventrally bent trajectories. The paradigm’s myelotomy blocked these pioneering fibers from stepping down the developmental cascade, rendering an unknown phenotype. This reflected a hypothetical transition hub stationed on the assembly line, delineating a critical period. The paradigm also affected the neuropil’s ripening independently from the long primary afferent system. The data disclosed that fetal hyposaturation yielded an in vivo genomic engineering capability. Fetal tissue was susceptible to hyposaturation, showing remarkable versatility early in fetal life. The translational impact may favor research into the elusive etiology of clinical syndromes concerning the afferent system relating to fetal hyposaturation. Full article

This review addresses the role of chemical communication in mammals, giving special attention to the vomeronasal system in pheromone-mediated interactions. The vomeronasal system influences many social and sexual behaviors, from reproduction to species recognition. Interestingly, this system shows greater evolutionary variability compared to the olfactory system, emphasizing its complex nature and the need for thorough research. The discussion starts with foundational concepts of chemocommunication, progressing to a detailed exploration of olfactory systems. The neuroanatomy of the vomeronasal system stands in contrast with that of the olfactory system. Further, the sensory part of the vomeronasal system, known as the vomeronasal organ, and the integration center of this information, called the accessory olfactory bulb, receive comprehensive coverage. Secondary projections of both the olfactory and vomeronasal systems receive attention, especially in relation to the dual olfactory hypothesis. The review concludes by examining the organization of the vomeronasal system in four distinct mammalian groups: rodents, marsupials, herpestids, and bovids. The aim is to highlight the unique morphofunctional differences resulting from the adaptive changes each group experienced. Full article

Introduction: Renal lobulation (also known as fetal or embryonic lobulation) is a rare variation during development in which renal lobules have a visible anatomical space between them, and this can be seen in 0.5–4% of adults. Material and methods: this study was conducted on 54 human kidneys from patients who died due to causes unrelated to renal pathology which were fixed in a 10% formaldehyde solution and then carefully dissected. Results: The group with fetal lobulation (n = 16) was associated with a length M = 9.89 (SD = 0.6, p = 0.15). By comparison, the kidneys without lobulation (n = 38) were associated with a numerically longer length M = 10.29 (SD = 0.607, p = 0.098). To test the hypothesis that lobulation is associated with a statistically significant different length a Mann–Whitney test was performed, which indicated that the length of the kidneys is smaller in scase of lobulation U = 198, Z = −2.04, p = 0.04. Cross-tabulation also demonstrated that kidney lobulation may be influenced by the presence of polar arteries with r = 0.41 (p < 0.02). The likelihood ratio was 7.28, df 1, p = 0.003, with an odds ratio of 6.857 (CI 95% = 1.84–25.61). Logistic regression analysis demonstrated that kidneys with lobulation were 6.85 times more likely to have polar arteries than kidneys without lobulation. Conclusions: the data from our research indicate that even though no pathological conditions have been linked with lobulated kidneys, the incidence of vascular variations (specifically polar arteries) is higher when there is persistent fetal lobulation. Full article

It is unclear whether differences between the two brain hemispheres become larger or smaller with increasing age. Given that the hippocampus is particularly susceptible to age-related changes, here, we set out to investigate the correlation between chronological age and hippocampal asymmetry, both for the hippocampal complex as a whole and in cytoarchitectonically defined subregions (cornu ammonis 1, 2, 3, dentate gyrus, subiculum, and entorhinal cortex). We analyzed T1-weighted data of the brain from a sample of 725 healthy individuals (406 women/319 men) spanning a wide age range (36–100 years) from The Lifespan Human Connectome Project in Aging. Correlations between the absolute asymmetry index and chronological age were positive for all six subregions and also for the hippocampal complex as a whole, albeit effects the effects were not significant for the dentate gyrus. This suggests that, overall, hippocampal asymmetry increases with increasing age (i.e., the left and right hippocampi become more different over time). Given that the subregions of the hippocampal complex serve different brain functions, follow-up research is needed to explore the functional implications within the framework of brain aging. In addition, longitudinal studies will be necessary to confirm the observed cross-sectional effects. Full article

Background: Anatomical variations and, in particular, arterial variations constitute an important chapter in the learning of Clinical Anatomy. Purpose: The purpose of this report is to describe a rare bilateral anatomical variation in the internal thoracic artery (ITA) in a 60-year-old corpse and to depict its extreme clinical importance in coronary artery bypass surgery. Methods: The rare bilateral aberrant branches of the internal thoracic artery and their course in the thorax were incidentally discovered during routine anatomy dissection of the thorax at the Faculty of Medicine and Medical Sciences of the University of Balamand. The findings were thoroughly documented using digital photography, and the dissection followed the instructions from the “16th Edition of Grant’s Dissector”. Results: In the observed case, the left aberrant branch of ITA descends laterally and gives medial and lateral anterior intercostal branches at the first six intercostal spaces. Conversely, the right aberrant artery, which branches from the ITA, descends laterally and gives medial and lateral branches to every intercostal space in the first five intercostal spaces. Conclusion: This report emphasizes that any unexpected variations in the lateral aberrant branches of the internal thoracic artery may complicate the surgical procedure. Bilateral aberrant lateral branches of the internal thoracic artery constitute rare anatomical variations of the internal thoracic artery and have been rarely reported in the literature. Such a course for aberrant lateral branches in the thorax poses possible lethal complications during several procedures involving the thorax, including basic coronary artery bypass graft, thoracocentesis and intercostal paracentesis and breast reconstruction. Full article

Understanding prostate carcinogenesis is crucial not only for identifying new treatment targets but also for developing effective strategies to manage the asymptomatic form of the disease. There is a lack of consensus about predicting the indolent form of the disease prostate cancer, leading to uncertainties regarding treatment initiation. This review aims to enhance the assessment and management of early prostate cancer by providing a comprehensive picture of the molecular anatomy of the prostate, synthesising current evidence, highlighting knowledge gaps, and identifying future directions. It presents evidence for the efficacy of active surveillance as an alternative treatment strategy and its potential benefits in specific patient groups through androgen receptor disruption. Overall, an improved understanding of prostate carcinogenesis and its molecular underpinnings can pave the way for tailored and precise management approaches for this common cancer. Further development and validation of molecule-based assessment tools are needed. Integrating genomic, proteomic, and phenotypic models, as well as functional approaches, can help predict outcomes. This facilitates selecting candidates for active surveillance and targeting interventions for higher-risk cases, contributing to more precise management strategies. Full article