Anatomical Science International最新文献

The vertebral artery (VA) supplies almost one-third of the blood flow to the brain, contributing mainly to its posterior circulation. This article provides a comprehensive overview of the different anatomical variations related to the origin, course, and termination of the VA and associated clinical implications. Data were compiled from numerous published studies accessed from the databases Medline, Scopus, Web of Science, Google Scholar, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Literature in Health Sciences (LILACS) as of January 2024. Methodological quality was evaluated with an assurance tool for anatomical studies (AQUA). Pooled prevalence was estimated using a random effects model, and differences in VA variant rates were assessed. VA variants were identified that could be separated into three categories: variation in origin, course, and terminal branches. A total of 16 studies met the established selection criteria for the current meta-analysis. VA variations were reported at an overall prevalence of 11% (CI: 7%–15%) and a heterogeneity of 77%. Statistically significantly higher rates were revealed in the following subgroups of the sample: imaging examinations versus cadavers (p = 0.032); right side of the body versus left (p = 0.034); and bilaterally versus unilaterally (p = 0.019). Concerns listed in included studies primarily focused on the possibility of iatrogenic damage during surgical procedures. A few studies also indicated higher rates of VA variants in patients who reported symptoms of recurrent headaches, vertigo, dizziness, and/or syncope. The presence of VA variants is high and can occur in various regions. However, the most important clinical consideration is that individuals with this variant must be constantly monitored since their posterior cerebral circulation could be affected. To avoid iatrogenic damage to the VA, clinicians should employ medical imaging to evaluate its course and branches prior to surgical interventions in the region.

In vivo functional imaging is a powerful tool for identifying the functional organization of the cerebral cortex. Flavoprotein autofluorescence imaging detects the metabolic activity of endogenous flavoprotein in neuronal tissue and thus provides an indirect measure of brain activity. As flavoprotein imaging is minimally invasive and does not require expensive equipment or reagents, it is easily combined with tract tracing methods and serves as a valuable approach for investigating functional organization of the brain. This paper provides a step-by-step protocol for flavoprotein imaging to record cortical activity in response to auditory stimuli, along with a method for injecting neuroanatomical tracers into functionally identified cortical regions. Key factors for obtaining reproducible results include stabile head fixation, a controlled dark imaging environment, maintenance of body temperature, and oxygen saturation monitoring.

Chemical fixation is essential in immunohistochemistry for detecting molecular localization. The gold-standard fixative for immunohistochemistry is 4% paraformaldehyde (PFA); however, its properties—such as tissue shrinkage and protein cross-linking through methylene bridges—often restrict antibody access, posing challenges to achieving specific binding reactions. This is particularly true for receptors and ion channels condensed in the synaptic cleft, postsynaptic density, or trigger zone of action potentials. To overcome this problem, several laboratories have attempted antigen-exposure techniques. Recently, we demonstrated that fixation by glyoxal, a dialdehyde with two carbon atoms, enables specific detection of molecular groups that are difficult to be detected in PFA-fixed tissues. Here, we summarize the advantages and precautions in the use of glyoxal fixative.

Neuroanatomy is emerging from decades of neglect, where the synthetic approach, a neuroanatomical hallmark, was too often, as an aspersion, dismissed as "descriptive." The resurgence is in part driven by new technical advances (e.g., better visualization tools; larger sample sizes), many of which are briefly described here and treated in more detail elsewhere in this Special Issue. Another factor is the over-due recognition that a seemingly "descriptive" approach can be positively compatible with synthesis, integration, and conceptual formulation. The first two sections of this brief overview highlight advances in the level of microscopic visualization and the increasing availability of large data sets ("big data"). Illustrative examples of specific applications are drawn from the literature. A last section briefly discusses how neuroanatomy might be expected to develop further as the field continues to move forward.

ATAC-seq (assay for transposase-accessible chromatin using sequencing) enables high resolution mapping of chromatin accessibility, providing critical insights into gene regulatory mechanisms in neuroscience research. This protocol presents an optimized approach for applying ATAC-seq to neural tissues and cells, addressing the unique challenges of preserving chromatin integrity in these delicate samples. We detail the key steps of tissue processing, nuclear isolation, transposition reactions, and library preparation specifically adapted for neural applications. The method requires minimal starting material (20,000–50,000 cells) while maintaining high sensitivity for detecting regulatory elements involved in neural development, plasticity, and neurological disorders. This tailored protocol facilitates robust investigation of neuroepigenomic regulation in diverse experimental contexts.

This study examines the effects of virtual reality (VR) and tablet-based mobile applications (TBMA) in teaching heart anatomy to middle school students. A randomized-controlled trial was conducted in which 84 middle school students were divided into three groups: VR (n = 28), TBMA (n = 28), and control (n = 28). The students' knowledge levels regarding heart anatomy were assessed before and after the applications. In addition, the student's metacognitive awareness and satisfaction levels were measured after the TBMA and VR applications. The participants' opinions regarding the applications were evaluated using qualitative analysis techniques. Descriptive statistics, variance analysis, and t tests were used to analyze quantitative data, and Colaizzi's education method was prepared sevenfold to examine qualitative data. A significant increase in heart anatomy knowledge levels was observed in the distribution of VR and TBMA. However, no significant difference was found between the groups (p > 0.05). In addition, while the metacognitive awareness of heart anatomy was higher in the students in the VR group, the students in the TBMA group were more satisfied with the learning process. Students stated that learning heart anatomy with VR and TBMA methods was fun, informative, and enjoyable and that such applications should be used more in classes. This study reveals that technology-supported teaching methods can positively affect students' learning processes while teaching heart anatomy. More comprehensive research should be conducted with randomized-controlled and mixed-method studies in different age groups and various course subjects to evaluate the sustainability and effectiveness of technology-based applications.

High-speed atomic force microscopy (HS-AFM) enables real-time visualization of biological processes with nanometer-level resolution. This review highlights how HS-AFM has been instrumental in uncovering the dynamic interplay between nuclear pore complexes (NPCs)—which regulate nucleocytoplasmic transport—and genome guardians, including DNA repair proteins and chromatin regulators. Structurally, the NPCs resemble a multi-layered spider cobweb, serving as crucial molecular gatekeepers for maintaining cellular homeostasis, while genome guardians safeguard genomic integrity through DNA repair and chromatin organization. Through HS-AFM, the researchers have gained unprecedented insights into NPC dynamics, revealing their adaptability during nuclear transport, chromatin reorganization, and viral infection. It has also elucidated how genome guardians interact with NPCs, influencing chromatin organization at the nuclear periphery and regulating nucleocytoplasmic trafficking. These discoveries underscore the critical role of NPC-genome interactions in genome stability, gene expression, and nuclear transport, with broad implications for diseases such as cancer, viral infections, and neurodegenerative disorders. In conclusion, HS-AFM has transformed our ability to study the nuclear landscape at the nanoscale, bridging the gap between structural biology and functional genomics. By capturing the real-time molecular dynamics of NPCs and chromatin, HS-AFM provides an essential tool for unraveling the mechanisms that govern nuclear transport and genome regulation. Future advancements in HS-AFM technology, including higher temporal resolution, correlative imaging, and AI-driven analysis, will further expand its potential in biomedical research, paving the way for novel diagnostic and therapeutic strategies.

Fibularis tertius muscle (FT) was first described by Vesalius in 1543 and was subsequently studied in detail by Henle and Hyrtl in the nineteenth century. There has been a controversy over whether FT is a separate beings. With regard to the question, it has been reported that the FT is an independent muscle or a part of the adjacent muscles such as the extensor digitorum longus muscle (EDL) and the extensor digitorum brevis muscle. In this study, to clarify the origin of the FT from the perspective of neuromuscular anatomy, gross and stereomicroscopic dissections and modified Shiler’s staining were performed on 48 sides of the lower legs from 25 Japanese cadavers. Of the 48 specimens, 43 specimens (89.6%) had a FT muscle belly, while 5 specimens (10.4%) did not. Most FTs were innervated by distal nerve branches from a common trunk with the EDL. The innervations of the FT and EDL suggest that the FT and EDL were brother muscles, and we proposed here a hypothesis that the FT and EDL originate from a common muscle mass and compete in a tug-of-war for muscle belly components during their development.