Anatomical Science International最新文献

{"title":"Dynamics of spinal cord and vertebral column development during the postnatal ontogenesis of the cat.","authors":"Polina Shkorbatova, Vsevolod Lyakhovetskii, Aleksandr Veshchitskii, Natalia Merkulyeva","doi":"10.1007/s12565-026-00965-3","DOIUrl":"https://doi.org/10.1007/s12565-026-00965-3","url":null,"abstract":"<p><p>Data on the structure and postnatal ontogenesis of the vertebral column and spinal cord are of great importance for neurobiology. The present study is devoted to a morphometric analysis of the spinal cord and vertebral column of the cat during the period from birth to adulthood. A complex pattern of postnatal development of both structures was revealed. It was established that the growth rate of vertebral length depends on the rostrocaudal position of the vertebrae: it is similar in VC3-VT10 and increases in the caudal direction, reaching a maximum in VL5. The growth rate of segment length demonstrates a more complex pattern: it decreases in the rostrocaudal direction (between segments C2-C3 and T2), then increases (up to T13), and decreases again (up to S3). At the same time, the growth rate of segments C7-T2 and L2-L7 is lower, whereas that of segments T4-T13 is higher than the growth rate of the corresponding vertebrae. As a result of this relationship between the growth rates of segment and vertebral lengths, a rostral displacement of the cervical and upper lumbar segments and a caudal displacement of the lower lumbar spinal cord relative to the corresponding vertebrae occurs. The growth rate of the spinal cord gray matter area is inversely proportional to the growth rate of segment length. We suggest that the divergent growth processes observed in different spinal cord segments underlie the postnatal formation of the cervical and lumbar enlargements, which contain the principal neuronal networks controlling body and limb motor functions.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148863220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A case of bilateral formation of common jugular vein by the confluence of the external and internal jugular veins.","authors":"Ayuki Nishiyama, Moeka Namba, Harutsu Nanno, Yuito Motoki, Yoshiya Sanada, Hiroyuki Kawai, Hayato Urushima, Masatake Kai, Makoto Kondo","doi":"10.1007/s12565-026-00967-1","DOIUrl":"https://doi.org/10.1007/s12565-026-00967-1","url":null,"abstract":"<p><p>The external jugular vein and internal jugular vein are the principal superficial and deep veins of the neck, respectively. The former descends along the lateral aspect of the sternocleidomastoid muscle and typically drains into the subclavian vein, whereas the latter descends through the neck and joins the subclavian vein to form the brachiocephalic vein. Here, we report bilateral anomalies involving the external and internal jugular veins in a 90-year-old Japanese female cadaver. In this case, the external jugular vein drained into the internal jugular vein at the lateral border of the sternocleidomastoid muscle, forming a venous trunk that may be described as a \"common jugular\" vein. The right and left \"common jugular\" veins measured 60.1 mm and 40.0 mm in length, respectively, and joined the ipsilateral subclavian veins. Anomalies were also detected in the surrounding veins, including the facial vein draining into the external jugular vein on the right side. Although cases of confluence of the external and internal jugular veins have been recorded with varying frequencies, detailed information about their morphology together with associated veins remains limited. The course of the external jugular vein is clinically important in neck surgery and central venous catheterization, therefore understanding venous anomalies such as those observed in the present case is clinically valuable.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148863244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disrupted myeloarchitecture accompanying anatomical abnormalities in the auditory pathway of reeler mice.","authors":"Fuduki Inoguchi, Amirlan Byambadash, Dai Ihara, Yu Katsuyama","doi":"10.1007/s12565-026-00966-2","DOIUrl":"https://doi.org/10.1007/s12565-026-00966-2","url":null,"abstract":"<p><p>Reelin plays a crucial role in neuronal migration and synaptic organization during brain development. Mice lacking Reelin (reeler mice) exhibit severe disorganization in cortical and cerebellar structures. Given that reeler mice show abnormal auditory brainstem responses, we investigated the cytoarchitecture and myeloarchitecture of major relay nuclei in the central auditory pathway. By Kluver-Barrera staining and Bielschowsky staining, we analyzed the primary auditory cortex, medial geniculate body, inferior colliculus, superior olivary nucleus, nucleus of the trapezoid body, and cochlear nucleus in reeler and wild-type mice. We observed marked structural abnormalities across multiple levels of the auditory pathway in reeler mice. These findings suggest that Reelin is essential for the proper structural development of auditory relay nuclei, and that its absence leads to widespread anatomical disorganization across both cortical and subcortical auditory regions. This structural disarray likely underlies the functional auditory deficits observed in reeler mice and underscores the critical role of Reelin in the formation of central auditory circuits.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148823956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A skeletal-smooth muscle interface mediates levator ani attachment to the rectum and vagina: a macroscopic and histological study.","authors":"Satoru Muro, Akimoto Nimura, Keiichi Akita","doi":"10.1007/s12565-026-00963-5","DOIUrl":"https://doi.org/10.1007/s12565-026-00963-5","url":null,"abstract":"<p><p>We aimed to clarify the attachment architecture between the levator ani and the rectum and vagina using integrated macroscopic and histological analyses of human pelvic floor specimens. Macroscopic dissection demonstrated whitish soft tissue at the interface between the levator ani and the lateral walls of the rectum and vagina. Histological and immune histochemical analyses of the corresponding regions revealed abundant smooth muscle components that appeared topographically continuous with the outer muscular layers of each organ within individual coronal sections. In both organs, the smooth muscle extended beyond the organ walls, spread over the superior and inferior surfaces of the levator ani, and interdigitated between skeletal muscle bundles, forming a serrated (saw tooth-like) interface. No dense connective tissue structures resembling tendons or aponeuroses were identified, indicating that levator ani-visceral attachment does not conform to a classical tendon-mediated enthesis. Distinct attachment patterns were observed between the two organs. At the rectal interface, a subset of levator ani muscle fibers coursed toward smooth muscle that appeared topographically continuous with the rectal longitudinal layer and formed an insertion-like arrangement. In contrast, at the vaginal interface, no insertion-like arrangement of levator ani muscle fibers into the vaginal wall was observed. Abundant vaginal smooth muscle extended laterally and enveloped adjacent levator ani muscle bundles. These findings provide a clearer anatomical characterization of a non-tendinous skeletal-smooth muscle interface between the levator ani and deformable pelvic visceral walls. This provides an anatomical basis for future studies investigating how the levator ani interacts mechanically with these deformable pelvic organs.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148786972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Histological effect of melatonin and its agonist on testes in light-exposure and pinealectomized rats.","authors":"Ismail M Maulood, Evan B Othman, Nazar M Shareef Mahmood","doi":"10.1007/s12565-026-00962-6","DOIUrl":"https://doi.org/10.1007/s12565-026-00962-6","url":null,"abstract":"<p><p>Melatonin (MEL), beyond its role as a pineal hormone, supports male reproduction by regulating circadian rhythms and exerting antioxidant and anti-apoptotic actions in the testes. Disruption of pineal function by pinealectomy and/or continuous light exposure is negatively correlated with spermatogenic activity and is linked to testicular degeneration. This study assessed testicular changes in MEL-deficient models and the capacity of MEL and the MEL-receptor agonist ramelteon (RAM) to ameliorate injury. Adult male albino rats underwent continuous light exposure and/or pinealectomy, then were allocated to control, untreated, MEL-treated, or RAM-treated subgroups. Animals in the continuous light model were exposed to constant light for 10 weeks, whereas animals in the pinealectomy model underwent surgical pinealectomy and were maintained for 9 weeks post-operatively. At the end of the experimental periods, animals were sacrificed and testicular tissues were collected for histological and morphometric evaluation. Seminiferous tubule area, diameter, and epithelial thickness were measured. Continuous light and pinealectomy caused marked disruption of germinal epithelium, epithelial cell and nuclear detachment, tubular necrosis, prominent vacuolar degeneration, widened interstitial spaces, and reduced spermatogenic activity, with the combined model showing the most severe damage. Melatonin treatment significantly improved tissue architecture and spermatogenic layering. Ramelteon produced greater recovery, approaching normal tubular organization and spermatogenesis. Morphometry confirmed reductions in tubule area, diameter, and epithelial thickness in melatonin-deficient rats, with improvement after melatonin and a larger improvement after RAM administration. Based on the histological findings of the present study, RAM treatment was associated with an overall improvement in the structural organization of the seminiferous epithelium compared with the untreated experimental groups. This was evidenced by better preservation of seminiferous tubule architecture, reduced epithelial disorganization, and improved morphometric indices. These findings support melatonergic therapies for preserving fertility during environmental circadian disruption in adult males.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Histological structure of entheses in the sacroiliac joint-related ligaments: implications for pain generation.","authors":"Daisuke Kurosawa, Hiraku Otaka, Keiju Kamijo, Eiichi Murakami, Tsukasa Kumai, Haruo Kanno, Hiroshi Ozawa","doi":"10.1007/s12565-026-00961-7","DOIUrl":"https://doi.org/10.1007/s12565-026-00961-7","url":null,"abstract":"<p><p>The sacroiliac joint (SIJ) consists of an articular surface and a large posterior ligamentous region, both essential to its function. However, the detailed histological structure of the posterior ligaments, including enthesis characteristics, is not well understood, which obscures our understanding of SIJ-associated pain. This study aimed to determine their histological features and potential contribution to pain generation. The SIJ-related ligaments, including the ligament-bone attachment sites (the sacrotuberous ligament [STL]: the sacrum site and the ischial tuberosity site, the sacrospinous ligament [SSP]: the ischial spine site, the long posterior sacroiliac ligament [LPSL]: the posterior superior iliac spine [PSIS] site and the third sacral tuberosity site, and the short posterior sacroiliac ligament: medial site of the PSIS) were harvested from 10 human cadaveric donors. Histological staining (hematoxylin-eosin and Alcian blue) and immunohistochemistry for aggrecan, collagen type Ⅱ, and PGP9.5 were performed to assess fibrocartilage presence and innervation. Alcian blue positivity was most frequent at the ischial tuberosity of the STL (100%) and the third sacral tuberosity of the LPSL (70%). Immunohistochemical staining for aggrecan and collagen type II confirmed the presence of extracellular matrix components of fibrocartilage in these regions, with concordance rates of 85.7% and 90.0%, respectively, compared to Alcian blue staining. Adipose tissue and PGP9.5-positive nerve fibers were observed adjacent to the ligament-bone attachment site. The ligament-bone attachments of SIJ-related ligaments, especially the STL and LPSL, exhibit fibrocartilaginous structures consistent with classical entheses. Additionally, the existence of nerve fibers in the adipose tissue around the SIJ-related ligaments indicated a potential source of pain.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148705121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anatomical variations of the suprascapular artery: correlation between origin and course.","authors":"Saburo Mori, Yuto Kawasaki, Ono Takafumi, Mio Imai, Daisuke Toyoda, Takayuki Miyaki, Koichiro Tujikawa, Keita Satoh, Juan Alejandro Oliva Trejo, Takuya Omotehara, Koichiro Ichimura","doi":"10.1007/s12565-026-00960-8","DOIUrl":"https://doi.org/10.1007/s12565-026-00960-8","url":null,"abstract":"<p><p>This study aimed to characterize the spectrum of anatomical variations in the origin and course of the suprascapular artery. We investigated the origin and course of 239 suprascapular arteries from 134 Japanese cadavers donated to Juntendo University School of Medicine for anatomical education. The suprascapular arteries were classified into six types based on their origin and course. Type 1, originating from the thyrocervical trunk, represented the most common and standard morphology (158/239, 66.1%). Type 2 arose from the proximal portion of the internal thoracic artery (15/239, 6.3%), and Type 3 originated directly from the second part of the subclavian artery (10/239, 4.2%). Types 1-3 passed superior to the superior transverse scapular ligament to enter the supraspinous fossa. Type 4 originated directly from the third part of the subclavian artery (50/239, 20.9%), whereas Types 5 and 6 arose from the superior thoracic artery (4/239, 1.7%) and the superficial subscapular artery (2/239, 0.8%), respectively. Types 4-6 traversed the scapular notch inferior to the superior transverse scapular ligament, accompanying the suprascapular nerve, to enter the supraspinous fossa. The brachial plexus sheath, which envelops the brachial plexus and adjacent arteries, was identified as a potential anatomical determinant of the correlation between the origin and course of the suprascapular artery. Type 1 represented the standard morphology of the suprascapular artery. Consistent with previous studies, the suprascapular artery exhibited considerable anatomical variation, with a distinct correlation between origin and course.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148683357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: A standardized technique for high-fidelity venous perfusion of human limbs for anatomical education and surgical skills training.","authors":"Jianhua Liu, Baohua Luo, XuYi Hu, Zhenfu Zhao, LiangJie Deng, Abudureyimujiang Ruze","doi":"10.1007/s12565-026-00959-1","DOIUrl":"https://doi.org/10.1007/s12565-026-00959-1","url":null,"abstract":"","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148652877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Persistent thyroglossal duct with a retrohyoid cyst containing pearl-like structures revealed by cadaveric dissection.","authors":"Nabil Eid, Gehan El-Akabawy, Yuko Ito, Ismail Abdul Sattar Burud, Nabeel Ibraheem Jaafar Albazah, Lakshmi Selvaratnam","doi":"10.1007/s12565-026-00957-3","DOIUrl":"https://doi.org/10.1007/s12565-026-00957-3","url":null,"abstract":"<p><p>The thyroglossal duct (TGD) is an embryonic fibrous tract that guides the descent of the thyroid gland from the tongue base to its definitive pretracheal location. Cadaveric studies reporting persistent TGD associated with cyst formation are rare. During routine dissection of the thyroid gland in an elderly female cadaver, we identified a persistent TGD arising from the left thyroid lobe and extending superiorly toward the left lateral border of the thyroid cartilage. A midsagittal section of the cervicocephalic region revealed superior extension of the TGD coursing posterior to the hyoid bone and terminating inferior to the tongue, where it formed a multilocular cyst containing nodular, pearl-like structures, consistent with a thyroglossal duct cyst (TGDC). To our knowledge, this is the first cadaveric report demonstrating an intact persistent TGD with a retrohyoid/infralingual course and intimately associated TGDC containing pearl-like nodules. This case highlights the retrohyoid space as a potential site of occult TGDCs with surgical and radiological relevance. It also underscores the importance of targeted anatomical dissection, including midsagittal sectioning, in identifying retrohyoid TGDCs that may remain clinically silent and anatomically hidden.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atlanto-occipital assimilation with arcuate foramen, vertebral artery hypoplasia, and elongated styloid process: a case report.","authors":"Taro Ito, Yui Yoshimura, Yayoi Ikeda","doi":"10.1007/s12565-026-00958-2","DOIUrl":"https://doi.org/10.1007/s12565-026-00958-2","url":null,"abstract":"<p><p>We encountered a partial type of atlanto-occipital assimilation (AOA), characterized by the fusion of the atlas (C1) with the base of the occiput, in a male cadaver during a student dissection course. The lateral mass and lateral part of the anterior arch of C1 were fused with the corresponding basilar part of the occipital bone on both of the right and left sides. The transverse process of C1 was involved in the fusion on the right side but not on the left side. The atlanto-occipital joint was obliterated on the right side, while it was present on the left side. Middle part of the anterior arch and the entire posterior arch were free of the occipital bone. The foramen magnum was stenosed and deformed due to the protrusion of the hypertrophied fused bone mass. Complete form of arcuate foramen (AF) was unilaterally present on the right side. A marked difference was observed in the diameters between the right and left vertebral arteries (VAs) at the C2-C6 levels, indicating right VA hypoplasia (VAH). In addition to these anomalies, the specimen had bilateral elongated styloid processes (ESPs). The coexistence of multiple anatomical variations, including AOA, AF, VAH, and ESP, in the same cadaver is rare. This report describes the observed anatomical characteristics and discusses the significance of these variations from morphological and clinical perspectives, thereby contributing to a deeper understanding of craniocervical anatomical variations.</p>","PeriodicalId":7816,"journal":{"name":"Anatomical Science International","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148519814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}