Two Types of Variational Arteries' Courses From the Superior Mesenteric Artery to Supply the Splenic Flexure: Gross Anatomical Study.

BACKGROUND: Complete mesocolic excision with central vascular ligation is a standard method for managing colon cancer. However, there is no consensus on its procedure, especially for cancer in the splenic flexure of the transverse colon. This is because various types of variational arteries are distributed to the region, and their running course below and near the pancreas leads to difficulty in ligating the artery. OBJECTIVE: To clarify the arterial distribution to the splenic flexure of the transverse colon using cadavers. DESIGN: The arteries in the transverse mesocolon distributed to the colon were dissected in cadavers, and their route was quantitatively visualized using drawing software. SETTINGS: This study was conducted at the Department of Anatomy, Tokyo Medical University. PATIENTS: Sixty cadavers donated to Tokyo Medical University in 2017-2021 were used. MAIN OUTCOME MEASURES: The arterial courses to the splenic flexure of the transverse colon in the mesocolon and their patterns were evaluated. RESULTS: We found 34 variational arteries distributed to the splenic flexure of the transverse colon. Most originated from the superior mesenteric artery and the middle colic artery, with their typical course below the pancreas. We identified another arterial course, crossing the mesocolon away from the pancreas toward the splenic flexure of the transverse colon. Furthermore, the origin of these arteries was not behind the pancreas and can be found in the caudal region of the pancreas. LIMITATIONS: We cannot discuss how the arteries within the transverse mesocolon are observed by CT examination. CONCLUSIONS: This study showed 2 types of arterial courses (below the pancreas and within the mesocolon) toward the splenic flexure of the transverse colon for the first time. In the latter case, the complete mesocolic excision with central vascular ligation is likely performed more easily than in the former. See Video Abstract. DOS TIPOS DE RECORRIDO VARIACIONAL DE LA ARTERIA DESDE LA ARTERIA MESENTRICA SUPERIOR PARA IRRIGAR EL NGULO ESPLNICO ESTUDIO ANATMICO MACROSCPICO: ANTECEDENTES:La escisión mesocólica completa con ligadura vascular central es un método estándar para el cáncer de colon. Sin embargo, no hay consenso sobre su procedimiento, especialmente para el cáncer en el ángulo esplénico del colon transverso. Esto se debe a que varios tipos de arterias variacionales se distribuyen en la región, y su recorrido por debajo y cerca del páncreas dificulta la ligadura de la arteria.OBJETIVO:Este estudio tuvo como objetivo aclarar la distribución arterial al SF del colon transverso utilizando cadáveres.DISEÑO:Las arterias en el mesocolon transverso distribuidas al colon fueron disecadas en cadáveres, y su ruta fue visualizada cuantitativamente utilizando un software de dibujo.AJUSTES:Este estudio se realizó en el Departamento de Anatomía de la Universidad Médica de Tokio.PACIENTES:Se utilizaron sesenta cadáveres donados a la Universidad Médica de Tokio en 2017-2021.PRINCIPALES MEDIDAS DE RESULTADO:Se evaluaron los cursos arteriales al ángulo esplénico del colon transverso en el mesocolon y sus patrones.RESULTADOS:Encontramos 34 arterias variacionales distribuidas al ángulo esplénico del colon transverso. La mayoría se originaron en la arteria mesentérica superior y la arteria cólica media, con su trayecto típico por debajo del páncreas. Identificamos otro curso arterial, cruzando el mesocolon alejándose del páncreas hacia el ángulo esplénico del colon transverso. Además, el origen de estas arterias no estaba detrás del páncreas y se pueden encontrar en la región caudal del páncreas.LIMITACIONES:No podemos discutir cómo se observan las arterias dentro del mesocolon transverso mediante un examen de tomografía computarizada.CONCLUSIONES:Este estudio mostró por primera vez dos tipos de trayectos arteriales (por debajo del páncreas y dentro del mesocolon) hacia el ángulo esplénico del colon transverso. En el último caso, es probable que la escisión mesocólica completa con ligadura vascular central se realice más fácilmente que en el primero. (Traducción-Dr. Aurian Garcia Gonzalez ).

Neurotransmission, Vasculogenesis, and Osteogenesis Activities are Altered in the Aging Temporomandibular Joint of the Senescence-Accelerated Prone 8 Mouse Model.

BACKGROUND: Alterations in neurotransmission, vasculogenesis, and osteogenesis pathways that may play pivotal roles in age-related changes in the temporomandibular joint (TMJ) are poorly understood. PURPOSE: This study aimed to measure the associations between gene and protein profiles in senescence-accelerated prone 8 (SAMP8) mice. STUDY DESIGN: The investigators designed and used 3 groups of 2 mouse models: 1) early aging SAMP8 at 24 weeks of age and control SAMR1 at 12 and 24 weeks (each stage n = 12). PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: The independent variable was investigated using 3 mouse models: an early aging mouse model and a control mouse model (12 and 24 weeks). MAIN OUTCOME VARIABLE(S): The primary outcome variables were CGRP, VEGF-A, CD31, LYVE-1, osteocalcin, osteopontin, type I and II collagen, and MMP-2. The secondary outcome variables were histological characteristics. COVARIATES: Not applicable. ANALYSES: The gene and protein expression profiles of neurotransmitters, vasculogenesis, and osteogenesis were identified by quantitative real-time polymerase chain reaction and dot blot analysis, respectively. The cellular localization of these events was verified by in situ hybridization and immunohistochemistry. Bivariate statistics were computed for each of the outcome variables. Statistical significance was set to a P value < .05. RESULTS: The expression of CGRP mRNA in the bony mandibular condyle (BMC) of SAMP8 mice (SAMP8, 3.3 ± 0.39 vs SAMR1, 0.001 ± 0.0001) was high at 24 weeks of age (24 weeks) (P < .001). Higher numbers of cells positive percentage for CGRP (MF, SAMP8, 28.67 ± 1.60 vs SAMR 1, 6.36 ± 1.10; CMC, 27.5 ± 2.12 vs 9.00 ± 1.21; BMC, 31.31 ± 2.81 vs 7.85 ± 1.14) and VEGF-A (MF, 34.43 ± 2.45 vs 14.01 ± 1.28; MD, 32.69 ± 1.86 vs 8.00 ± 0.91; CMC, 36.60 ± 2.05 vs 14.19 ± 1.25 BMC 36.49 vs 12.59 ± 1.41) antibodies were found in the 24 weeks TMJ (P < .01). CONCLUSIONS AND RELEVANCE: The neurotransmitter, vasculogenesis, and osteogenesis pathways are associated with TMJ aging in the SAMP8 mouse model. In the future, the SAMP8 mouse model may prove to be a robust model for identifying molecular and biochemical events underlying the effects of feeding, occlusal changes, and tooth loss in the aging TMJ.

Expression of neurotransmitters, vasculogenesis markers and myosin heavy chain isoforms in the masseter muscle of senescence-accelerated mouse prone 8 mice.

BACKGROUND: Learning and memory deficits and pathologic changes in the hippocampus caused by toothlessness and soft diet feeding are related to reduced masseter muscle (MM) function. OBJECTIVE: Myosin heavy chain (MyHC) isoform expression in the MM also changes under different chewing conditions. The neurotransmitter calcitonin gene-related peptide (CGRP) and vascular endothelial growth factor A (VEGF-A) are involved in MM formation. However, the relationship between CGRP, VEGF-A and MyHC isoforms in the MM in the senescence-accelerated mouse prone 8 (SAMP8) strain, a model of learning and memory deficits, remains unclear. METHODS: Changes in CGRP, VEGF-A, vasculogenesis marker and MyHC isoform mRNA expression in the MMs of ageing SAMP8 and senescence-accelerated mouse resistant 1 (SAMR1) mice was investigated through quantitative real-time polymerase chain reaction (qRT-PCR) and in situ hybridization. RESULTS: qRT-PCR revealed obviously high CGRP levels in the SAMP8 mouse MM (p < .001). MyHC-IId/x mRNA expression in the MM was higher in 24-week-old SAMP8 mice than 24-week-old SAMR1 mice (p < .001) but lower in slow-MyHC SAMP8 mice than SAMR1 mice (p < .001). CGRP mRNA was observed on the muscle fibres of the SAMP8 mouse MM but not the SAMR1 mouse MM through in situ hybridization. Principal component analysis (PCA) revealed strong positive contributions of SAMP8-MyHC-IId/x, SAMP8-CGRP, SAMR1-MyHC-emb, SAMR1-CGRP, SAMR1-VEGF-A, SAMR1-CD31, SAMP8-VEGF-A, and SAMP8-CD31 in the MM at 12 and 24 weeks. CONCLUSION: Calcitonin gene-related peptide is also key for the MyHC-IId/x and slow-MyHC patterns in the MMs of SAMP8 mice.

Structural and CBCT analysis of mandibular canal microvessels expressing neurotransmitters in human cadavers.

PURPOSE: This study focused on the detailed structure of microvessels of the neurotransmitter-positive vasa nervorum of the inferior alveolar nerve, vein, and artery in the mandibular canal (MC) to obtain information for improved safety in dental treatments. We also observed the detailed structure of the MC from the mental foramen to the mandibular foramen using cone-beam computed tomography (CBCT). METHODS: In this study, mandibles from 45 sides of 23 human cadavers aged 76-104 years were examined by microscopy, immunohistochemistry, and CBCT analysis. These data were further evaluated by principal component analysis (PCA). RESULTS: The microvessels of the vasa nervorum with calcitonin gene-related peptide- and neuropeptide Y-positive reactions were classified into 5 types: large (4.19%, 28/667); irregular large (7.35%, 49/667), numerous intermediate (29.23%, 195/667), irregular intermediate (29.23%, 195/667), and scattered fine (30.0%, 200/667) microvessels. The MC showed various structures from the 3rd molar to the premolars and was also classified into three types, including complete (57.0%, 228/400), partial (33.8%, 135/400), and unclear (9.2%, 37/400), from the mandibular foramen to the mental foramen. PCA results revealed that developed capillaries were mainly localized in the molar region. CONCLUSIONS: Fine microvessels of the vasa nervorum expressing neurotransmitters are present from the molar to premolar region, which is key information for mandibular dental treatments. The different microvessel structures also indicate differences in specific characteristics between dentulous and edentulous cadavers regarding oral surgical and implant treatments.

Three-dimensional structure of the facial canal and related blood vessels and nerves in the temporal bone.

PURPOSE: There are only limited anatomical data on nerves, veins, and arteries in the temporal bone. More detailed anatomical data are required to improve planning of treatments targeting the temporal bone region. Herein, we performed a detailed analysis of the facial canal (FC) and the related carotid artery and vein. METHODS: We examined the bony structure of the middle ear and FC, jugular foramen, and carotid canal in 30 Japanese elderly donor cadavers. Three-dimensional reconstruction of the canal structure was achieved using cone beam computed tomography, while macroscopic and histological analyses were also performed. RESULTS: The FC form was classified as either straight (28%) or bent (72%). There were significant differences in the diameter of the FC and the distance between the internal jugular vein, other FC branches, and the FC. Principal component analysis (PCA) was performed for the FC using 29 factors. Two principal components significantly explained 30.9% (component 1, 18.6%; component 2, 12.3%) of the FC. Histological observation showed numerous ganglion cells and shrunken neurons in the geniculate ganglion of the facial nerve of elderly samples. CONCLUSION: FC diameter is an important contributor to the relationship between the FC and the jugular foramen. The FC and the internal jugular vein are located close to each other, which is useful information for the trans-canal surgery of the otology. Furthermore, the geniculate ganglion contains numerous ganglion cells and shrunken neurons, which may affect the FC structure during bone matrix remodeling with aging.

The interrelationship between three-dimensional foot mobility and bodyweight bearing.

[Purpose] To clarify the three-dimensional nature of foot mobility and its interrelationships within the foot due to bodyweight bearing. [Participants and Methods] Data regarding left foot mobility due to body weight bearing were collected from 31 healthy adults. Foot shape differences while sitting and standing, and their interrelationship were examined. The same examiner reapplied the landmark stickers when misaligned during measurement position changes. [Results] The foot length, heel width, forefoot width, hallux valgus angle, and calcaneus eversion angle were significantly larger in the standing than in sitting position. The digitus minimus varus angle was significantly smaller in the standing than in sitting position. The medial and lateral malleoli, navicular, and dorsum of the foot were displaced medially and inferiorly; the other indices, except for the midfoot, were displaced anteriorly. The interrelationships within the foot showed a positive correlation between the calcaneus eversion angle and the medial displacement of the medial and lateral malleoli, navicular, and dorsum of the foot points. There was a negative correlation between the calcaneus eversion angle and inferior displacement of the medial malleolus, navicular, and dorsum of the foot. [Conclusion] The intra-foot coordination relationship in response to bodyweight bearing was clarified.

Relationship between the thoracic asymmetry in standing position and the asymmetry of ankle moment in the frontal plane during gait.

[Purpose] We aimed to investigate the relationship of thoracic asymmetry in standing position with asymmetry of the internal ankle moment in the frontal plane during gait. [Participants and Methods] The following measurements were recorded in 22 healthy adult males using a 3D motion analyzer and force plates: thoracic lateral deviation, asymmetrical ratios of the upper and lower thoracic shape, internal ankle moment in the frontal plane, mediolateral deviations of the center of mass and center of pressure. [Results] In the standing position, the thorax was deviated to the left relative to the pelvis, and the upper and lower thoracic shapes were asymmetrical. During gait, significant lateralities were observed in the internal ankle moment in the frontal plane, mediolateral deviations of the center of mass and the center of pressure. Significant positive correlations were observed between the asymmetrical ratio of the lower thoracic shape and both the asymmetry of the internal ankle moment in the frontal plane and the mediolateral deviation of the center of pressure. [Conclusion] These results suggest that thoracic asymmetry is associated with mediolateral control of the ankle during gait.

Relationship between the bilateral ratios of the thoracic shape and electromyographic activity of the thoracic and lumbar iliocostalis muscles during thoracic lateral translation.

[Purpose] This study aimed to determine the relationship between thoracic lateral deviation, the bilateral ratio of the thoracic shape, and the bilateral ratio of the thoracic and lumbar iliocostalis muscles during resting sitting and thoracic lateral translation. [Participants and Methods] We included 23 healthy adult males in the study. The measurement tasks were resting sitting and thoracic lateral translation relative to the pelvis. The thoracic lateral deviation and bilateral ratio of the upper and lower thoracic shapes were measured using three-dimensional motion capture. The bilateral ratio of the thoracic and lumbar iliocostalis muscles were measured using the surface electromyographic recording. [Results] The bilateral ratio of the lower thoracic shape was significantly positively correlated with the thoracic translation distance and the bilateral ratio of the thoracic and iliocostalis muscles. In addition, the bilateral ratio of the thoracic iliocostalis muscles was significantly negatively correlated with the bilateral ratios of the lower thoracic shape and lumbar iliocostalis muscles. [Conclusion] Our findings showed that the asymmetry of the lower thoracic shape is associated with left lateral deviation of the thorax at rest and thoracic translation distance. In addition, the thoracic and lumbar iliocostalis muscle activity differed between the left and right translations.

Relationship between scapular elevation exercises with different alignments and activity of the trapezius and levator scapulae muscles.

[Purpose] This study aimed to examine whether scapular elevation exercises in sitting positions with different alignments lead to contractions of the trapezius and levator scapulae muscles. [Participants and Methods] The participants were 25 males, measured in four sitting positions with different alignments. Spine alignment was assessed by measuring the head protrusion, upper thoracic spine tilt, and pelvic tilt angles. Upper limb alignment was evaluated using the scapula tilt angle, scapula rotation angle, and distance between scapular spinous processes. Scapular elevation exercises were measured, and the thickness of the trapezius and levator scapulae muscles were measured in resting and elevated positions, with changes in muscle thickness. [Results] The trapezius muscle thickness was greater in the sitting position with less thoracic spine tilt and scapula tilt angles. Conversely, the levator scapulae muscle thickness was greater in the sitting position with more thoracic spine tilt and scapula tilt angles. [Conclusion] Scapular elevation exercises induce separate contractions of the trapezius and levator scapulae muscles by modifying the alignment of the spine and upper limbs.

GIT1 is an untolerized autoantigen involved in immunologic disturbance of spermatogenesis.

Male haploid cells, spermatids and spermatozoa, that appear after the establishment of immune tolerance express novel cell surface and intracellular proteins that can be recognized as foreign antigens by the self-immune system. However, these germ cells do not normally evoke a pathological immune response. The immune-privileged micro-circumstance in testis involving the blood-testis-barrier formed by Sertoli cells protects these germ cells from autoimmune attack. We recently found that immunization with heat shock protein family A member 4-like (HSPA4L), one of the new differentiation antigens of haploid cells, induced experimental autoimmune orchitis (EAO) in A/J male mice. In this study, we focused on G protein-coupled receptor kinase interacting protein-1 (GIT1), another haploid cell-specific differentiation antigen, to investigate whether GIT1 is a target autoantigen for EAO induction. GIT1 emulsified with complete Freund's adjuvant was injected subcutaneously into the mice inguinal region once on day 0 and again on day 14, and the optimum condition of EAO induction was determined. Mice immunized with 200 µg GIT1 showed significantly higher incidence of EAO than that of immunization with other concentrations. In particular, significant lymphocytic inflammation and extensive aspermatogenesis were observed in these mice at 120 days after the first immunization. These findings indicate that GIT1 is also a target antigen that induces EAO, like HSPA4L.

Neonatal maternal separation causes decreased numbers of sertoli cell, spermatogenic cells, and sperm in mice.

Neonatal maternal separation is an experimental model used to evaluate the effects of toxic stress in neonates, or early life stress. Although various physiological and psychological stresses during childhood have been reported, the effects of neonatal maternal separation on the male reproductive system remain unclear. Therefore, the present study evaluated the effects of neonatal maternal separation on the male reproductive system. In neonatal male ICR mice, maternal separation was performed for 0.5, 1, 2, and 4 hours/day, from postnatal day 1 to 10. At 10 weeks of age, the neonatal maternal separation mice exhibited decreases in both testicular weight and epididymal sperm number, along with various testicular morphological changes involving germ cells, Sertoli cells, and interstitial cells. Notably, neonatal maternal separation mice showed decreased numbers of Sertoli cells. Animals subjected to 0.5-, 1-, and 2-h/day neonatal maternal separation exhibited decreases in serum levels of testosterone but not in those of gonadotropin (luteinizing hormone and follicle-stimulating hormone). Together, these data showed that neonatal maternal separation in male mice causes decreased Sertoli cell numbers following puberty, resulting in subsequent decreased spermatogenic activity.

Effects of the posterior pelvic tilt sitting posture on thoracic morphology and respiratory function.

[Purpose] We investigated how differences in pelvic angle in the posterior pelvic tilt sitting posture simultaneously affect the thoracic morphology and the respiratory function. [Participants and Methods] The participants were 18 healthy young males. We positioned the pelvis at 0°, 10°, 20°, and 30° of posterior tilt, following which the thoracic expansion volume ratio, thoracic spine tilt angle, and respiratory function were measured. We calculated the thoracic volume and thoracic spine tilt angle by measuring the amount of displacement of reflective markers attached to the thoracic area using the Vicon MX 3D-analysis system. Respiratory function was measured by spirometry. [Results] The expansion volume ratio decreased significantly in response to 10-30° posterior pelvic tilt sitting at the mid-thorax and 30° posterior pelvic tilt sitting at the lowest thorax. The upper thoracic spine level showed a change in anterior tilt at 10-30° posterior pelvic tilt sitting, whereas the lower thoracic spine level showed a change in posterior tilt at 30° posterior pelvic tilt sitting. Respiratory function was significantly lower at 30° posterior pelvic tilt sitting than at 0° posterior pelvic tilt sitting. A positive correlation between thoracic expansion volume ratio and respiratory function was found at 30° posterior pelvic tilt sitting. [Conclusion] Changes in thoracic spine tilt angle due to posterior pelvic tilt sitting may restrict the expansion of thoracic motion during respiration, thereby affecting respiratory function.

Pelvic collateral pathway during endovascular aortoiliac aneurysm repair with internal iliac artery interruption: a retrospective observational study.

BACKGROUND: Ipsilateral branches of the deep femoral artery (DFA) are qualitatively identified as collateral arteries based on angiography after internal iliac artery (IIA) interruption. The purpose of this study was to quantitatively identify the major collateral pathway after unilateral IIA interruption during endovascular aortoiliac aneurysm repair to preserve the pelvic circulation and reduce the risk of ischemic complications. METHODS: The study population included 28 patients (mean age 76.3 years) with aortoiliac aneurysm who underwent endovascular aneurysm repair with unilateral IIA interruption from August 2012 to January 2020. The diameters of the bilateral preoperative and postoperative DFA, lateral femoral circumflex artery (LFCA), medial femoral circumflex artery (MFCA) and obturator artery (ObA) were measured on contrast-enhanced computed tomography using a 3-dimensional image analysis system. The measured values were evaluated and analyzed with a repeated measures two-way analysis of variance and Dunnett's test. RESULTS: The postoperative diameters of the MFCA (P = 0.051) and ObA (P = 0.016) were observed to be larger than the preoperative diameters. Such increases in the MFCA (P < 0.001) and ObA (P < 0.001) diameters were only found to be significant on the unilateral side of the IIA interruption, and the diameter of the ipsilateral LFCA (P < 0.001) was also found to have significantly increased in size. However, no significant arterial extension was found on the contralateral side. CONCLUSIONS: The ipsilateral MFCA-ObA pathway might therefore be a major collateral pathway arising from the DFA to preserve pelvic circulation after unilateral IIA interruption.

Third primary branch of the posterior ramus of the spinal nerve at the thoracolumbar region: a cadaveric study.

PURPOSE: Spinal column procedures require an accurate understanding of neural pathways relative to the anatomic structure. Since Bogduk's report in 1982, it has been known that the human lumbar posterior ramus of the spinal nerve (PRSN) comprise not two but three primary branches at least in some lumbar segments. The purpose of the current study was to examine the existence of the three primary branches in the thoracic and lumbar segments. METHODS: In this study, we investigated the anatomy of the human PRSN in the thoracic and lumbar segments. Ventral dissection was performed in eight cadavers to determine the anatomy of the PRSN between T1 and L5. RESULTS: At the distal end of a given PRSN, the PRSN divided into three primary branches-medial, intermediate and lateral-in 196 out of 272 segments in the thoracic and lumbar regions in eight cadavers. The medial branch supplied the spinalis compartment, and reached the skin. The lateral branch supplied the iliocostalis muscle compartment, and reached skin. The intermediate branch supplied the longissimus muscle and the area between the medial and the lateral branch, which was a seemingly shorter branch. CONCLUSION: The triplication of the primary branch of the PRSN is considered not uncommon. The third branch should be recognized in the literature and in textbooks.

Effects of female bone marrow transplantation on male reproductive organs.

Graft-versus-host disease (GVHD), an adverse effect after bone marrow transplantation (BMT), may affect male reproductive function. It is hypothesized that a sex-mismatched BMT induces GVHD in male reproductive organs because female immune cells are not immunologically tolerant to specific antigens of the male organs. However, this hypothesis has not been experimentally verified using male (M) recipient animals following BMT from the female (F) donors. Therefore, the aim of the present study is to examine whether the female BMT to males (F→M group) induces some GVHD reactions in the testis and the other male reproductive organs. The results showed that no inflammation was found in recipients of the male BMT to males (M→M group), whereas significant inflammatory cell responses lasting for at least 4 months were induced in testis, epididymis, prostate and preputial gland in some mice of F→M group. The most severe lesion was found in the preputial gland, in which lymphocytic inflammation was accompanied by loss of glandular acini, thickening of the interstitum and increased cytokines such as TNF-α and IFN-γ. Western blot analyses revealed that sera from the F→M group reacted with various antigens of the male reproductive organs. These results indicate that transplanted female immune cells may recognize the male reproductive organs as immunologically foreign ones and induce chronic GVHD, which may affect male reproductive function.

Distribution of Contractile Structures in a Mouse and Human Lymph Node Associated with Lymph Flow.

Lymph nodes have contractile structures, but their distribution in a lymph node has been less considered in terms of facilitation of lymph flow. Axillary, inguinal, and mesenteric lymph nodes were collected from mice and human cadavers, and their sections were immunostained for alpha-smooth muscle actin (αSMA) and high molecular weight caldesmon (H-caldesmon). The αSMA-positive cells were localized in the capsule beneath the ceiling epithelium on the afferent side in both mice and humans. We found an additional layer of the αSMA-positive cells in the human lymph node, surrounding the inner layer perpendicularly. H-caldesmon was expressed only in these cells of the outer layer. In some human lymph nodes highly containing fat tissue in the medulla, the capsule disappeared on the efferent side, resulting in a disrupted sinusoidal lymph pathway. These findings suggest that human lymph nodes have additional smooth muscles in the outer region of the capsule to facilitate lymph flow. The αSMA-positive cells in the outer and inner layers of human lymph nodes probably have different functions in contraction. The presence of lipomatosis in a human lymph node will reduce its contribution to the lymph flow.

Training on skin flap elevation in hand surgery using cadavers embalmed by the saturated salt solution method: effectiveness and usefulness.

Thiel embalmed and fresh-frozen cadavers have been mainly used for hand surgery training. We held a training seminar on skin flap elevation using cadavers embalmed by the saturated salt solution method. This study aimed to evaluate the usefulness of such training and to validate the suitability of saturated salt solution-embalmed cadavers for hand surgery training. Participants were trained in elevation procedures for the oblique triangular, reverse digital artery, reverse radial forearm, and reverse dorsal metacarpal artery flaps. Forty-eight surgeons participated in three seminars (one held in 2017, 2018, and 2019 each). A self-assessment of the participants' confidence levels for their surgical skills was performed before and immediately after the seminar, and the suitability of saturated salt solution-embalmed cadavers was determined in terms of visual perception, tactility, comparison with real-world surgical settings, and usefulness. The confidence level for all skills increased immediately after the seminar. The surgeons reported that the visual perception and tactility of the saturated salt solution-embalmed cadavers were comparable to those of a living body, and the cadavers were rated higher with respect to their usefulness. Hand surgery seminars using cadavers embalmed by the saturated salt solution method are considered useful for training in skin flap techniques.

Efficacy of urea solution reperfusion to a formalin-embalmed cadaver for surgical skills training.

Formaldehyde has been traditionally used for embalming human cadavers for gross anatomy education and surgical skills training. However, exposure to formaldehyde negatively affects human health. This study aimed to assess the efficacy of reperfusing urea solution to a formalin-embalmed cadaver for surgical skills training and then investigate the cadaver's tissue elasticity alteration after being soaked into the urea solution. Twelve surgeons evaluated the similarity of tissue characteristics between the cadaver (embalmed by formalin solution and reperfused by urea solution) and a living human body. Furthermore, the tissue formaldehyde content and mechanical properties of the formalin-fixated femoral skin and artery specimens with or without soaking into urea solution were measured. Results showed that the tactile assessment, skin incision, vessel ligation and suture, and decollement were better and more useful in the cadaver reperfused by urea solution than in the cadaver merely fixated by formalin solution. In the urea-reperfused cadaver, the volatilized, or tissue formaldehyde levels declined. The stiffness and Young's modulus of the femoral skin and artery were also lower in the specimen than in the mere formalin-fixated specimen. In conclusion, reperfusion of urea solution to the formalin-fixated cadaver makes anatomical education and surgical skills training more efficient with fewer requirements for cadaver management.

A case of double inferior vena cava with the connection to sacral venous plexus.

Double inferior vena cava (IVC) is known as a variation in which the additional IVC is found on the left side of the abdominal aorta. Their developmental process has been well documented, but the venous development around the lumbosacral region is controversial. In the present double IVC case, the left IVC entered the left renal vein at the L2 level, and the renal veins on each side flowed into the right IVC at the L1 level. The internal and external iliac veins were merged at the S1 level on each side. Besides, a venous communication (3-mm-width) was found horizontally between the internal iliac veins near their origin at the S1 level. It had also an extra narrow branch (1-mm-width), which ran obliquely upward and reached the left IVC at the level of L5. The median sacral artery (MSA) ran at the ventral side of the horizontal communication but at the dorsal side of its extra oblique branch. These results suggest that the oblique branch is a remnant of the anastomosis between the right and left posterior cardinal veins. Furthermore, the horizontal vein corresponds to the sacral venous plexus, suggesting that the anastomosis can be formed between the IVC and sacral venous plexus.

Neonatal corticosterone administration increases p27-positive Sertoli cell number and decreases Sertoli cell number in the testes of mice at prepuberty.

Cortisol and corticosterone (CORT) are steroid, antistress hormones and one of the glucocorticoids in humans and animals, respectively. This study evaluated the effects of CORT administration on the male reproductive system in early life stages. CORT was subcutaneously injected at 0.36 (low-), 3.6 (middle-), and 36 (high-dosed) mg/kg body weight from postnatal day (PND) 1 to 10 in ICR mice. We observed a dose-dependent increase in serum CORT levels on PND 10, and serum testosterone levels were significantly increased only in high-dosed-CORT mice. Triiodothyronine levels were significantly higher in the low-dosed mice but lower in the middle- and high-dosed mice. However, testicular weights did not change significantly among the mice. Sertoli cell numbers were significantly reduced in low- and middle-dosed mice, whereas p27-positive Sertoli cell numbers increased in low- and middle-dosed mice. On PND 16, significant increases in testicular and relative testicular weights were observed in all-dosed-CORT mice. On PND 70, a significant decrease in testicular weight, Sertoli cell number, and spermatozoa count was observed. These results revealed that increased serum CORT levels in early life stages could induce p27 expression in Sertoli cells and terminate Sertoli cell proliferation, leading to decreased Sertoli cell number in mouse testes.