[Purpose] To investigate the relationship between thoracic asymmetry in the seated position, sagittal head position, and trunk movement patterns during the sit-to-stand motion. [Participants and Methods] Twenty-three healthy adults participated. Using a three-dimensional motion analysis system, we calculated the anteroposterior diameter ratios (right/left) of the upper and lower thorax at rest and measured the sagittal displacement of the head relative to the thorax. During the sit-to-stand task, we analyzed trunk movement relative to the pelvis and hip joint flexion-extension angles. [Results] Of the 23 participants, 20 exhibited leftward thoracic deviation relative to the pelvis. In these cases, trunk flexion preceded hip flexion, reaching maximum flexion before the hip joint. Significant leftward trunk rotation also occurred during the transition from flexion to extension, compared with that in the initial position. A correlation was observed between upper thoracic asymmetry and trunk flexion and between forward head displacement and trunk flexion. [Conclusion] Thoracic asymmetry and sagittal head position were associated with trunk movement patterns during sit-to-stand. These factors may be important considerations for physical therapy interventions aimed at improving sit-to-stand performance.

N-type right-sided aortic arch is a subtype of the Adachi-Williams-Nakagawa`s classification for variations in branching patterns of the aortic arch. Kommerell's diverticulum is a rare anomaly and characterized by the aneurysmal dilatation of the proximal portion of an anomalous subclavian artery or of the aorta at the origin of such subclavian artery. Kommerell's diverticulum occurs in association with a right-sided aortic arch with aberrant left subclavian artery. In the present study, we report a cadaver case of N-type right-sided aortic arch accompanied by Kommerell's diverticulum in retroesophageal origin of the left subclavian artery. Interestingly, in this case, the double left brachiocephalic vein was identified around the ascending aorta. To our knowledge, there have been no reported cases of the coexistence of right-sided aortic arch, Kommerell's diverticulum, and double left brachiocephalic vein. The right-sided aortic arch is often associated with congenital heart diseases and other cardiovascular abnormalities. Therefore, the present right-sided aortic arch with Kommerell's diverticulum and double left brachiocephalic vein may give us an important knowledge for cardiovascular anomalies in men from both clinical and embryological aspects.

Background:Free flap reconstruction after wide resection of sarcomas around the knee is challenging due to anatomical complexity and limited recipient vessels. The medial vastus branch of the descending genicular artery (DGA) may serve as a favorable recipient artery, but its anatomical characteristics and clinical applicability remain unclear. Methods:An anatomical study was conducted on 30 lower limbs from 15 formalin-fixed cadavers to investigate the course and diameter of the medial vastus branch of the DGA. In addition, the clinical applicability of this vessel was evaluated in knee reconstruction. Results:The medial vastus branch was identified in 86.7% of specimens, with an average diameter of 1.4 mm (range: 1.0-1.7), 1.6 mm (range: 1.2-1.9), 1.7 mm (range: 1.3-2.0), and 1.9 mm (range: 1.6-2.3), at 2.5, 5.0, 7.5, and 10-cm above the medial upper margin of the patella. Its superficial location allowed for easy dissection and anastomosis. The medial vastus branch of the DGA was successfully used as a recipient artery for free flap transfer in clinical application. Conclusion:The medial vastus branch of the DGA is a reliable recipient artery for free flap reconstruction around the knee. Its favorable anatomical characteristics enable safe dissection and vascular anastomosis without the need for positional changes during surgery. This vessel may be a valuable option for complex soft tissue reconstructions around the knee defects.

Adachi type VI is a rare celiac artery (CA) variant in which the left gastric and splenic arteries form a gastrosplenic trunk. In this type, the common hepatic artery (CHA) and superior mesenteric artery (SMA) arise from a hepatomesenteric trunk, and the CHA passes posterior to the portal vein (PV). In addition, a common trunk formed by the inferior pancreaticoduodenal artery (IPDA) and the first jejunal artery (J1A) has been reported in anatomical studies. However, to our knowledge, the concurrent presence of Adachi type VI together with a posteriorly originating IPDA-J1A common trunk has not been previously reported. A 93-year-old male cadaver donated to Tokyo Medical University was examined. The arterial system of the upper abdomen was observed macroscopically, and arterial diameters and branching patterns were recorded. A gastrosplenic trunk arose from the abdominal aorta (AA) and divided into the left gastric artery (LGA) and splenic artery (SA). Inferior to the gastrosplenic trunk, a hepatomesenteric trunk arose from the AA and divided into the CHA and SMA, corresponding to Adachi type VI. In addition, the IPDA and J1A arose from a common trunk originating from the posterior aspect of the SMA. The coexistence of these variations could reflect the persistence of ventral splanchnic arterial segments that normally regress during embryonic development. Clinically, procedures such as Appleby's operation and distal pancreatectomy with CA resection can compromise hepatic and gastric perfusion, although collateral pathways from the SMA may compensate in some cases. Therefore, understanding arterial variations such as the present case is important from both anatomical and clinical perspectives.

BACKGROUND:Intraoral anastomosis is a widely used technique for microvascular alveolar ridge augmentation and midface reconstruction. However, the predictable anatomical positioning of facial structures, such as the vessels, parotid duct, and facial nerve in the buccal region, has remained unclear. Therefore, we aimed to obtain the anatomical characteristics of these locations to establish surgical landmarks for the intraoral anastomosis of facial vessels. METHODS:A total of 26 sides from 13 formaldehyde-fixed cadavers approximately a month after fixation with a mean age at death of 86.6 ± 11.2 years (range: 55-104 years) were anatomically examined. Facial vessels, nerves, and the parotid duct were dissected intraorally. From the oral cavity side, the X-axis was defined as the line from the labial commissure to the lowest point of the intertragic notch. RESULTS:From the oral cavity side, all branches of the facial nerve were found under the facial artery and vein. The positioning order along the X-axis was the facial artery, vein, and parotid duct exit. The facial artery was 21.3 ± 2.2 mm and the facial vein was 39.2 ± 2.7 mm from the labial commissure. Ninety-two percent of facial veins were found within 15-20 mm of the facial artery on the X-axis. The parotid duct exit was 46.8 ± 2.0 mm from the labial commissure. In the buccal region, the vessel calibers of the facial artery and vein were 1.8 ± 0.2 and 2.1 ± 0.2 mm, respectively. CONCLUSION:Knowledge of the anatomical relations among the facial artery, vein, parotid duct, and facial nerve from the oral cavity side can enhance the safety and efficacy of midface reconstruction surgeries involving intraoral anastomosis procedures.

Duplicated inferior vena cava (DIVC) is a congenital anomaly where the inferior vena cava (IVC) is present on either side of the abdominal aorta. Previous studies have noted smaller IVC widths in DIVC cases, but detailed structural characteristics remain unclear. This study aimed to characterize the histological structure of the IVC in DIVC and normal cases. Histological analysis was performed on the IVC just below the liver (IVC-Liver), the IVC at the 4th lumbar vertebra level (IVC-L4), and the external iliac vein (EIV) from donated cadavers. The tissues underwent HE staining and immunohistochemistry to detect elastin and alpha smooth muscle actin, with the cross-sectional area of vessel lumina and immunopositive area calculated. The study found that the combined cross-sectional areas of the right and left IVC-L4 in DIVC cases were smaller than the single IVC-L4 area in normal cases. Histologically, DIVC cases showed a significantly decreased ratio of elastin immunopositive areas, compared to normal cases. This reduction in cross-sectional areas and elastin ratio suggests that IVCs in DIVC cases hold less blood volume and have weaker contractility by elastic fibers after dilation, potentially leading to disrupted blood circulation in the lower body.

Cadaveric surgical training (CST) can safely improve surgical skill. Recently, various innovations have made surgical training more realistic. Saturated salt solution (SSS) and urea methods are useful for plastic surgery training, because they better preserve the color and texture of soft tissues than formalin fixation (FA). Microvessels are invisible to the naked eye, and in this study, we visualized skin perforators by injecting dye into the flaps of nutrient vessels during hand and foot surgery. During each CST session, the instructor used three cadavers for demonstration. From 2017 to 2021, these cadavers were not stained, whereas from 2022 to 2023, the cadavers were stained to enhance the visualization of nutrient and perforating vessels. We compared the self-rated skill gains of participants who observed demonstrations on unstained cadavers from 2017 to 2021 and participants who observed demonstrations on stained cadavers from 2022 to 2023. Among 36 participants from the 2022–2023 group, 28 rated the staining of nutrient vessels and perforating branches as adequate. Of 32 participants, 29 preferred the use of dyed cadavers during training. Trainee skill increase for the digital artery flap, reverse digital artery flap, and dorsal metacarpal artery perforator flap was significantly higher in 2022–2023 (with stained cadavers) than in the earlier course without stained cadavers. SSS-fixed and urea-treated cadavers combined with vascular staining may be useful training models for flap elevation.

BACKGROUND:That the peroneus tertius muscle (PT) is a separate entity has been long debated. PT has been variously reported to be part of the extensor digitorum longus muscle, part of the extensor digitorum brevis, or a separate muscle. While pigs have a PT as well as primates, there are no reports of its association with the extensor digitorum longus muscle or extensor digitorum brevis. MATERIALS AND METHODS:In this study, we used gross dissection and Sihler's staining to determine the origin, course, insertion, and innervation of the pig PT. RESULTS:The PT and extensor digitorum longus muscles jointly originated from the femur and ran between the tibialis cranialis and peroneus longus muscles. The PT was inserted at the retinaculum of the metatarsal extensors, tarsal bone, and second metatarsal bone. The branches of the common fibular nerve to the extensor digitorum longus muscle were distributed to the PT. CONCLUSIONS:The innervations suggest that the PT and extensor digitorum longus muscles of the pig were derived from the same muscle mass during development, but were named separately due to differences in their morphology. Furthermore, morphological features suggest that pig PT and human PT are probably different muscles.

Cortisol/corticosterone (CORT) are typical glucocorticoids and exert an anti-stress function. p27, a cyclin-dependent kinase inhibitor, acts as a terminal factor for Sertoli cell proliferation at the prepubescent stage. Our previous study showed neonatal CORT administration increased p27-positive Sertoli cells followed by decreasing Sertoli cells in mice. The present study evaluated the effects of CORT and/or RU 486, a glucocorticoid receptor antagonist, on Sertoli cells in early life stages. CORT and/or RU 486 were subcutaneously injected to ICR mice, from postnatal days (PNDs) 1 to 10, at doses of 0.36 and 0.0006 mg/kg body weight, respectively. Testes from control, CORT-, RU 486 + CORT-, and RU 486-administered mice were evaluated on PNDs 4, 10, and 16. RU 486 administration blocked CORT-induced increase of relative p27-positive Sertoli cells, with the resultant recovery of Sertoli cell numbers to control level. RU 486 administration alone unexpectedly caused decreases in Sertoli cells. The present study is the first to reveal that activation of glucocorticoid receptors following CORT administration in early life stages is involved in p27-positive Sertoli cell and total Sertoli cell number in vivo, suggesting that appropriate glucocorticoid signaling in early life stages is required for the intact proliferation and maturation of Sertoli cells.

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.

Tenomodulin (TNMD) is related to chondromodulin-1, a cartilage-derived growth regulator. It is specifically expressed in hypovascular connective tissues, including tendons and ligaments. Vascular endothelial growth factor A (VEGF-A) and calcitonin gene-related peptide (CGRP) correlate with angiogenesis and neurogenesis, respectively, during development. Because of that the morphological profiles of TNMD, VEGF-A, and CGRP distributions in developing diaphragm are still unclear, we aimed to determine the expression of mRNA and proteins of these 3 markers during the development of the central tendon of the diaphragm (CTD) and the surrounding diaphragm tissue in mice. Male mice from the embryonic and postnatal periods [embryonic day 14.5 (E14.5), E17.5, postnatal day 1 (P1), and P5] were used and their mRNA and protein expressions were assessed using in situ hybridization, immunohistochemistry and quantitative real-time polymerase chain reaction. The results showed that TNMD was preferentially detected in muscle-tendon junction of the CTD at E17.5 and P1, in contrast to scattered distribution of CGRP and VEGF-A throughout the diaphragm from E14.5 to P5. These findings may provide fundamental information concerning the role of the TNMD in the CTD development.

BACKGROUND:A simple and easy-to-use method for recording jaw muscle activity is important for minimising the need for specialised expertise in electrode placement, reducing the burden on the subject. OBJECTIVE:This study aimed to determine whether masseter muscle activity analysis by sound myography (SMG) combined with laser displacement-induced skin movement sensing (LDSMS) is comparable to surface electromyography (SEMG). METHODS:Eight healthy volunteers (21.0 ± 1.67 years) were included in the study. The measurement tasks consisted of clenching (CL), maximum jaw opening (MJO) and jaw closing and biting (JCB). Masseter muscle activity was recorded simultaneously using SMG, LDSMS and SEMG. We analysed the frequency amplitude spectrum using wavelet analysis and relationships between the signals from the three measurement methods (SMG, LDSMS and SEMG) using principal component analysis (PCA). RESULTS:The masseter muscle activity during jaw tasks analysed using SMG, LDSMS and SEMG was clearly defined. The peak of the integral time-frequency power (ITFP) (mV2/Hz) of the SMG was indicated by approximately CL, 9.8 ± 0.9, JCB, 10.5 ± 1.4 and MJO, 11.3 ± 1.4 Hz. The peaks of the LDSMS (CL, 4.2 ± 0.5, MJO, 4.2 ± 0.5 and JCB, 4.4 ± 0.6 Hz) and SEMG (CL, 54.7 ± 4.6 MJO, 102.1 ± 9.9 and JCB, 71.7 ± 9 Hz) were shown. PCA analysis revealed clusters of masseter muscle activity during jaw tasks obtained by the SMG, SEMG, and LDSMS devices. CONCLUSION:The SMG with the LMSMS by wavelet analysis is a simple and easy-to-use method that can be used to detect jaw muscle activity issues.

BACKGROUND:Acute inflammation is induced by lipopolysaccharide (LPS), accompanied by activation of platelets. Carbon monoxide (CO), an endogenous bioactive gas, has been shown to bind to mitochondria and exert anti-inflammatory effects. In this study, we investigated the effect of CO on the mitochondrial membrane potential of platelets activated by LPS. METHODS:To elucidate the mechanism of the LPS-induced platelet response, human platelets were stimulated with LPS (10 μg/mL). Human platelet concentrates were divided into four groups: Untreated (Control), LPS-treated (LPS), LPS and CO-dissolved solution-treated (LPS + CO), and LPS and exogenous carbon monoxide releasing molecule-2-treated (LPS + CORM-2) groups. After 30 minutes, lactate levels and mitochondrial membrane potential (ΔΨm) in the platelets were measured. Morphological changes of the platelets were also observed using transmission electron microscopy. RESULTS:In the LPS group, the proportion of platelets with depolarized ΔΨm increased, accompanied by elevated lactate levels compared with the control group. On the other hand, in the LPS+CO and LPS+CORM-2 groups, the proportion of depolarized platelets did not significantly increase, and lactate levels were not significantly elevated. Morphologically, elongating pseudopods and cell condensation were observed in the LPS group, however, these changes were not induced in the LPS+CO and LPS+CORM-2 groups. CONCLUSION:These results suggest that CO prevents a decrease in the platelet ΔΨm and thereby inhibits platelet activation by LPS treatment.

BACKGROUND:The aim is to reveal the basic morphology of the infrahyoid muscles by proposing a new classification system. MATERIALS AND METHODS:Data were analyzed from 67 sides from 34 Japanese cadavers. We propose a new classification system for the infrahyoid muscles, dividing them into 12 areas: superficial (S) and deep (D), cranial (1, 3, 5) and caudal (2, 4, 6), lateral (1, 2), intermediate (3, 4) and medial (5, 6). This system integrates morphology and innervation pattern of these muscles more accurately. In the superficial layer, top of the intermediate tendon of the omohyoid muscle serves as the boundary between the cranial and caudal parts. In the deep layer, the thyroid cartilage represents the boundary. Additionally, innervation by the cranial and caudal branches of the ansa cervicalis is a required criterion for classification. RESULTS:The incidences for six areas - S1, S2, S5, S6, D3, and D4 - exceeded 99%, with this pattern observed in 71.6% of cases, suggesting that these may represent standard anatomical patterns. In contrast, areas such as S3, S4, D1, D2, D5, and D6 showed lower incidences. Notably, three novel anatomical variations were observed and described in detail. CONCLUSIONS:The proposed classification system allows for a more comprehensive understanding of the basic morphology of the infrahyoid muscle variation. Clinically, this is relevant for surgical procedures involving the infrahyoid area, such as flap reconstruction, where unexpected variations may occur surgical risks. Therefore, the proposed classification system offers anatomical and surgical framework of the infrahyoid muscles.

Previous studies have reported that the lateral meniscus (LM) has two regions, the popliteal hiatus area (PH) with a scarce blood supply and the roots with an abundant one. However, the description of its vascular anatomy remains insufficient. We hypothesized that the difference in the width of the meniscus hilum (MH) affects the scarcity and abundance of blood supply to the LM. The MH is a concept proposed by us and is the only site of entrance or exit of blood vessels and nerves associated with the meniscus. The purpose of this study was to provide a structural explanation for the disparity of blood supply to the LM using the concept of MH. Sixteen knees were examined to investigate the blood supply to LM. In most areas, the femoral joint capsule (FJC) and tibial joint capsule (TJC) continued to the cranial and caudal edges of the LM, respectively. In the roots, the FJC and TJC covered the femoral and the outer-femoral surfaces. In contrast, the FJC in the PH did not attach to the cranial edge and only the TJC there did to the caudal edge of the LM. Histochemical examination showed that the blood vessels enter the LM via the MH. In the PH, the MH at the caudal edge was extremely narrow; and in the roots, the MH on the outer-femoral surfaces was wide. The results suggest that the difference in the width of the MH affected the scarcity and abundance of blood supply to the LM.

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. (c) 2023 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 82:19-35, 2024

Busulfan is an anticancer drug known to cause serious damage to seminiferous tubules in the testes and deplete germ cells in human and animal models. The testicular artery is anastomosed with deferential and cremasteric arteries and is divided into capsular arteries, which give rise to the centripetal arteries and then recurrent arteries. The arterial blood in the testicular tissue is supplied by such a consequent system of arterial vessels, in order from the peripheral to the central area. As anticancer drugs are generally distributed throughout the whole body via the bloodstream and the running and distribution of arteries differ among the testicular areas, we hypothesized that the efficacy of busulfan differs in different testicular areas, particularly between the central and peripheral areas. In this study, busulfan was intraperitoneally injected at 40 mg/kg body weight into C57BL/6J male mice. After 28 days, in busulfan-treated mice, the diameters of seminiferous tubules were significantly higher in the central than in the peripheral area of the testes. The seminiferous tubular areas also significantly decreased in the peripheral areas compared with the central areas. The number of germ cells per seminiferous tubule was significantly higher in the central than in the peripheral area. Sertoli cell nuclei were detached into the lumen in the peripheral area. The number of Leydig cells was significantly lower in the peripheral areas. These data suggest that the effects of busulfan differ between the central and peripheral areas of the testis at 4 weeks after busulfan administration.

Systemic inflammatory response syndrome (SIRS) is a potentially fatal reaction to various forms of tissue damage and infections that cause damage to various organs. Furthermore, the brain is damaged earlier than other organs, resulting in diffuse brain dysfunction. The central clinical symptom of SIRS is delirium and emotional changes are involved in disease development. Although the amygdala is known to play a major role, the mechanisms underlying emotional changes in the early stages of SIRS have not been elucidated. Therefore, changes to dopamine levels in the amygdala were observed using an in vivo model of lipopolysaccharide (LPS)- induced SIRS to clarify the biochemical mechanisms activated in the early stages of SIRS. Extracellular dopamine was collected from the amygdala of free moving rats via microdialysis and then analyzed by high-performance liquid chromatography. In addition, emotional changes were assessed with the open field and sucrose preference tests. In the LPS group, dopamine release in the amygdala increased remarkably immediately after LPS administration, peaking at 120 min. Thereafter, dopamine release temporarily decreased, but then significantly increased again after 180 min. The present results suggest that diffuse brain dysfunction in the early stages of SIRS may involve altered dopamine levels in the amygdala.