A macroscopic anatomical study of the appropriate palpation zone of the gluteus medius muscle.

[Purpose] Few previous studies have delimitated the palpation zone of the gluteus medius muscle with a focus on its fiber bundles. The purpose of this study was to clarify the morphological characteristics of the gluteus medius muscle using an anatomical approach, and to define its proper palpation zone. [Participants and Methods] In this study, we evaluated thirteen halves of the pelvic region in seven formalin-fixed cadavers. We identified the borders between the iliotibial band and gluteus medius muscle, and between the gluteus medius and gluteus maximus muscles, on the iliac crest. Furthermore, we quantified the border points of the gluteus medius' fiber bundles and observed its anatomical and morphological characteristics. [Results] We identified two fiber bundles in the gluteus medius muscle, an anterior and a posterior fiber bundle, and detected that a portion of the posterior fibers was located subcutaneously. [Conclusion] We propose that the region where the posterior fibers of the gluteus medius muscle are located subcutaneously is an appropriate zone for the palpation of this muscle.

Role of TrkA signaling during tadpole tail regeneration and early embryonic development in Xenopus laevis.

Neurotrophic signaling regulates neural cell behaviors in development and physiology, although its role in regeneration has not been fully investigated. Here, we examined the role of neurotrophic signaling in Xenopus laevis tadpole tail regeneration. After the tadpole tails were amputated, the expression of neurotrophin ligand family genes, especially ngf and bdnf, was up-regulated as regeneration proceeded. Moreover, notochordal expression of the NGF receptor gene TrkA, but not that of other neurotrophin receptor genes TrkB and TrkC, became prominent in the regeneration bud, a structure arising from the tail stump after tail amputation. The regenerated tail length was significantly shortened by the pan-Trk inhibitor K252a or the TrkA inhibitor GW-441756, but not by the TrkB inhibitor ANA-12, suggesting that TrkA signaling is involved in elongation of regenerating tails. Furthermore, during Xenopus laevis embryonic development, TrkA expression was detected in the dorsal mesoderm at the gastrula stage and in the notochord at the neurula stage, and its knockdown led to gastrulation defects with subsequent shortening of the body axis length. These results suggest that Xenopus laevis TrkA signaling, which can act in the mesoderm/notochord, plays a key role in body axis elongation during embryogenesis as well as tail elongation during tadpole regeneration.

The E3 ubiquitin ligase Hace1 is required for early embryonic development in Xenopus laevis.

BACKGROUND: HECT domain and ankyrin repeat containing E3 ubiquitin protein ligase 1 (HACE1) regulates a wide variety of cellular processes. It has been shown that one of the targets of HACE1 is the GTP-bound form of the small GTPase Rac1. However, the role of HACE1 in early development remains unknown. RESULTS: In situ hybridization revealed that Xenopus laevis hace1 is specifically expressed in the ectoderm at the blastula and gastrula stages and in the epidermis, branchial arch, kidney, and central nervous system at the tailbud stage. Knockdown of hace1 in Xenopus laevis embryos via antisense morpholino oligonucleotides led to defects in body axis elongation, pigment formation, and eye formation at the tadpole stage. Experiments with Keller sandwich explants showed that hace1 knockdown inhibited convergent extension, a morphogenetic movement known to be crucial for body axis elongation. In addition, time lapse imaging of whole embryos during the neurula stage indicated that hace1 knockdown also delayed neural tube closure. The defects caused by hace1 knockdown were partly rescued by knockdown of rac1. Moreover, embryos expressing a constitutively active form of Rac1 displayed phenotypes similar to those of embryos with hace1 knocked down. CONCLUSIONS: Our results suggest that Xenopus laevis hace1 plays an important role in early embryonic development, possibly via regulation of Rac1 activity.

A molecular mechanism that links Hippo signalling to the inhibition of Wnt/ß-catenin signalling.

The Hippo signalling pathway has emerged as a key regulator of organ size, tissue homeostasis, and patterning. Recent studies have shown that two effectors in this pathway, YAP/TAZ, modulate Wnt/ß-catenin signalling through their interaction with ß-catenin or Dishevelled, depending on biological contexts. Here, we identify a novel mechanism through which Hippo signalling inhibits Wnt/ß-catenin signalling. We show that YAP and TAZ, the transcriptional co-activators in the Hippo pathway, suppress Wnt signalling without suppressing the stability of ß-catenin but through preventing its nuclear translocation. Our results show that YAP/TAZ binds to ß-catenin, thereby suppressing Wnt-target gene expression, and that the Hippo pathway-stimulated phosphorylation of YAP, which induces cytoplasmic translocation of YAP, is required for the YAP-mediated inhibition of Wnt/ß-catenin signalling. We also find that downregulation of Hippo signalling correlates with upregulation of ß-catenin signalling in colorectal cancers. Remarkably, our analysis demonstrates that phosphorylated YAP suppresses nuclear translocation of ß-catenin by directly binding to it in the cytoplasm. These results provide a novel mechanism, in which Hippo signalling antagonizes Wnt signalling by regulating nuclear translocation of ß-catenin.

Double superior vena cava and anomaly of cardiovascular system with a review of the literature.

In a student course of gross anatomy dissection at Kanagawa Dental College in 2008, we found an extremely rare case of the double superior vena cava that has a shunt between the right and left atria of a 81-year-old Japanese male cadaver. The left superior vena cava passed through the space between the left cardiac auricle and the left pulmonary vein and entered the coronary sulcus. Then it opened near the opening of the inferior vena cava as the coronary venous sinus to the right atrium. The upper edge of the interatrial septum was located at the site where the right superior vena cava opened to the right atrium. Accordingly, the right atrium connected with left atrium through this site. We discuss the anatomy and etiology of these anomalous structures with a brief review of the literature.

Anomalous bifurcation and island formation of the carotid artery.

An anomalous artery directly connecting the common carotid artery and internal carotid artery was discovered on the right side in the cadaver of an 83-year-old Japanese female, and the facial artery, maxillary artery, and superficial temporal artery arose from the common carotid artery by a common trunk. The anomalous artery arose from the posterior aspect of the common carotid artery at the level of the origin of the superior thyroid artery, and joined the posterior aspect of the internal carotid artery. The anomalous artery was covered by the connective tissue surrounding the common carotid artery and the internal carotid artery. The anomalous anastomosis, especially the proximal portion, may have arisen from the second branchial arch artery during development.

An odontometric study of the maxillary molars in Australian marsupials. I. The koala (Phascolarctos cinereus).

Crown dimensions of the maxillary molars were measured in the koala (Phascolarctos cinereus). There were no significant differences in crown diameters between the first and second molars, however the fourth molars were reduced in all crown diameters. The third molar was smaller than the first or second molars in buccolingual crown diameters but there were no significant differences in mesiodistal crown diameters. It is proposed that the similar shapes of the first and second molars are associated with similar types of masticatory activity involving these teeth, The shape of the third molar, which is reduced in size buccolingually, may be linked to the koala's occlusal function which is characterized by a condylar action that leads to differences in movement between opposing anterior and posterior molar teeth during the occlusal stroke. The fourth molar, the smallest of the molar teeth in crown diameter, erupts significantly later than the other molars, and its reduction may be explained by the terminal and distal reduction theories. It is proposed that the pattern of molar morphology in the koala is associated with both masticatory activity linked to its characteristic occlusal function, as well as reflecting the sequence of tooth emergence.

Regional differences in D/L aspartic acid ratios in the human mandible as a possible indicator of the bone remodeling rate.

In slowly metabolizing tissue such as tooth, bone and ocular lens, D-amino acids converted from L-amino acids accumulate with age and thus reflect the tissue turnover rate. To investigate whether D-amino acids play a role in determining the bone remodeling rate, we measured the accumulation of D-aspartic acid, which has the fastest rate of racemization, in various areas of the mandible. The level of D-aspartic acid was higher in the ramus than in the body (P < 0.01), and within the body, the level was higher in the basal area than in the alveolar area (P < 0.01). Within the alveolar area, the level of D-aspartic acid was higher in the molar region than in the incisal region (P: 0.05-0.01). No correlation was found between the accumulated level of D-aspartic acid with age, because all the specimens were obtained from elderly people with only a few years difference in age. There was also no correlation between D-aspartic acid and sex. In conclusion, we suggest that accumulation of D-aspartic acid in the mandibular bone reflects the differences in remodeling associated with occlusion. The incisal portion of the alveolar area of the mandible (above the mandibular canal), shows the greatest evidence of active remodeling.

An anomalous case of the hepatic artery arising from the superior mesenteric artery.

In a stdudenet course of gross anatomy dissection at Kanagawa Dental College in 2006, we found an extremely rare case of the hepatic artery arising from the superior mesenteric artery of a 78-year-old Japanese male cadaver. This case belonged to type V in Adachi's classification of the celiac trunk and the superior mesenteric artery (1928). The gastro-splenic trunk and hepato-mesenteric trunk both arose from the abdominal aorta and the left gastric artery arose from the gastro-splenic trunk. The hepatic artery arose from the hepato-mesenteric trunk and crossed the portal vein anteriorly.

The retroesophageal right subclavian artery - A case report and review.

In a student course of gross anatomy dissection at Kanagawa Dental University in 2011, we encountered anomalous case of the right subclavian artery arising from the aortic arch as the last branch in an 84-year-old Japanese male cadaver. The anomalous artery ran obliquely upward, passed behind the esophagus and trachea, and ultimately ran toward right scalene gap. The area of distribution of the anomalous artery was normal. We report a case of retroesophageal right subclavian artery, and discuss its development, or relation with the thoracic duct, and its clinical importance. Despite this type of variation being relatively rare, reports on such a case have been accumulating. Owing to the recent development of CT and MRI, the number of clinical reports on this anomaly has been increasing.

Microcirculation alterations in experimentally induced gingivitis in dogs.

The present study aimed to morphologically examine the gingival microvascular network using a microvascular resin cast (MRC) technique, and to investigate how inflammatory disease functionally affects gingival microcirculation using laser Doppler flowmetry (LDF). We used four beagle dogs with healthy periodontal tissue as experimental animals. To cause periodontal inflammation, dental floss was placed around the cervical neck portions of the right premolars. The unmanipulated left premolars served as controls, and received plaque control every 7 days. After 90 days, gingivitis was induced in the experimental side, while the control side maintained healthy gingiva. To perform morphological examinations, we used an MRC method involving the injection of low-viscosity synthetic resin into the blood vessels, leading to peripheral soft-tissue dissolution and permitting observation of the bone, teeth, and vascular cast. Gingival blood flow was estimated using an LDF meter. The control gingival vasculature showed hairpin-loop-like networks along the tooth surface. The blood vessels had diameters of 20-40 µm and were regularly arranged around the cervical portion. On the other hand, the vasculature in the experimental group was twisted and gathered into spiral forms, with blood vessels that had uneven surfaces and smaller diameters of 8-10 µm. LDF revealed reduced gingival blood flow in the group with experimentally induced gingivitis compared to controls. The actual measurements of gingival blood flow by LDF were in agreement with the alterations that would be expected based on the gingivitis-induced morphological alterations observed with the MRC technique.

A Study of the Maxillary Sinus Volume in Elderly Persons Using Japanese Cadavers.

In this paper, using full-body CT images of elderly and advanced elderly Japanese cadavers, we measure maxillary and other paranasal sinus volumes in order to examine the effects of age, sex, presence or absence of maxillary molars, and other factors on changes to maxillary sinus volume. The research subjects consisted of 77 of 95 cadavers donated to the Kanagawa Dental University between 2012 and 2014, which average age was 82.6 ± 10 years (33 were male, average age 79.3 ± 8.3 years, and 44 were female, average age 85.1 ± 11.7 years). Sinus volume was measured from full-body CT images on the horizontal plane and computed using the 3D volume rendering software. The average maxillary sinus volume was 31.3 ± 13.2 cm3 (average value ± one standard deviation; hereafter the same), with values of 32.9 ± 13.2 cm3 (6.7 cm3 ～ 55.7 cm3) for males and 29.6 ± 12.5 cm3 (5.5 cm3 ～ 52.9 cm3) for females. In this report, we studied the effects of aging, sex, and state of remaining molars on changes to paranasal sinus volume in the maxillary sinus. These results give additional information about maxillary sinus volume of Japanese oldest-old peoples.

Morphological observation of the horseshoe kidney with special reference to the vascular system in 2 Japanese cadavers.

Two cases of the horseshoe kidney in Japanese cadaver were reported in this paper. The kidneys and their associated vessels in the retroperitoneal cavity were carefully examined, and the histological examination of the isthmus was performed. In Case 1, four arteries arose from the abdominal aorta. One right and two left renal arteries were distributed to the apical, upper, middle and posterior regions of the kidney, respectively, and the artery of isthmus entered the lower segments and the isthmus. In Case 2, six arteries arose from the abdominal aorta. Among three arteries arose from the inferior end of the aorta and entered the lower segments and the isthmus. Histological study revealed that the isthmuses consisted of collecting tubes, glomeruli and urinary tubules and fibrous connective tissue. The incidence of the horseshoe kidney during the dissecting practice at Tokyo Medical University in a period of 24 years from 1980 to 2003 was estimated to be 0.16% (2 out of the 1,219 cadavers). The anatomical and embryological significance of this anomaly and its associated vascular system were discussed. And the histology of the parenchymal structure of the isthmus in the horseshoe kidney containing either fibrous connective tissue or renal parenchyma was also analyzed in this report.

Short-term prophylaxis with deoxyspergualin prevents testicular autoimmunity in mice.

The effects of the treatment with the immunosuppressant deoxyspergualin on the development of experimental autoimmune orchitis were studied. The results showed that C3H/He mice immunized with testicular germ cells and treated daily with either 0.3 or 3 mg/kg body weight deoxyspergualin during days 15-20 post-immunization developed experimental autoimmune orchitis lesions with a significantly lower incidence and severity than did the control mice treated under the same experimental conditions with phosphate buffered saline (PBS). The effects of deoxyspergualin were clearly dose-dependent, and the higher dose of the drug also markedly reduced the degree of delayed type hypersensitivity responses against testicular germ cells. These data suggest that deoxyspergualin may be worthy of consideration for the prevention/treatment of human immunoinflammatory orchitis.

Anatomical study of distribution of valves of the cutaneous veins of adult's limbs.

Since the cutaneous veins of the four limbs have been used as autogenous grafts in the treatment of cardiovascular disorders, knowledge of distribution of the valves is increasingly required depending upon the use. In the gross anatomical study of distribution of valves of the trunci venae, there has been argument about locational relationships between the venous roots and the valves in the vicinity of the roots and the inter-valvular distance. However, there have been only few reports discussing detailed information about valves of the cutaneous veins of the four limbs. The authors observed patterns of distribution of the cutaneous venous valves of the four limbs of cadavers prepared for practice in anatomy. The following parts were excised from each cadaver: the cephalic, basilic, and the great saphenous veins, which originate from the acral venous network and flow into the proximal deep veins, and the venous roots communicating with these veins. An incision was made on each excised vein in the direction of the long axis under observation with a stereoscopic microscope, and the inter-valvular distance and the distance between the valve and the orifice of venous root in the vicinity of the valve were measured. The inter-valvular distance varied with type of the truncus venae, and it varied according to area even in the same truncus venae.

Toluene diisocyanate exposure induces laryngo-tracheal eosinophilia, which can be ameliorated by supplementation with antioxidant vitamins in guinea pigs.

OBJECTIVE: Toluene diisocyanate (TDI)-induced asthma is a common cause of occupational lung disease. In addition, a sore throat is one of the complaints of TDI-exposed workers. The aim of the present study was to determine whether TDI exposure induces laryngeal and/or tracheal lesions in experimental animals. MATERIAL AND METHODS: Guinea pigs underwent naris application of TDI three times, and their respiratory tracts were then examined using light and electron microscopy. Some animals simultaneously received vitamins C and E. which function as antioxidant agents. RESULTS: When TDI-treated animals showed the clinical sign of labored breathing, many eosinophils had appeared in the lamina propria and mucosa of both the larynx and trachea, which finally infiltrated the tract lumen through the ruptured epithelium. Laryngo-tracheal inflammation was more severe than that observed in the lungs. However, supplementation with antioxidant vitamins in TDI-treated animals ameliorated the respiratory eosinophilia. CONCLUSION: Naris application of TDI induced laryngotracheitis. which was significantly suppressed by the antioxidant vitamins, This implies a preventive effect of the vitamins on this occupational disease.

Three cases of the gastrosplenic and the hepatomesenteric trunks.

Three common branches of the celiac trunk are the left gastric artery, the splenic artery and the common hepatic artery. The variation of the three branches of the celiac trunk has an importance for the arterial supply to the digestive organs of the upper abdomen. In this study, we present three cases of the gastrosplenic and the hepatomesenteric trunks in Japanese cadavers. Especially, in Case 1, the left inferior phrenic artery arose from the gastrosplenic trunk and the left hepatic artery arose from the left gastric artery. In Cases 2 and 3, the common hepatic artery penetrated the pancreatic parenchyma before reaching liver. In Case 3, the right hepatic artery arose from the hepatomesenteric trunk.

Anatomical study of meandering and functions of human intralaryngeal artery.

In recent years, partial laryngectomy and partial reconstruction are increasingly intended for conservation of functions of phonation and swallowing. In partial reconstruction, it is important to comprehend morphological characteristics of the blood vessels distributed in the larynx, but there have been only few reports discussing detailed information about them. Previous reports on laryngeal blood vessels have shown that branches of some arteries show remarkable "meandering". In the present study, we devised a method for objectively determining the morphological nature, "meandering" and assessed functions of the arteries. Intralaryngeal arteries were excised from the larynx of cadavers prepared for practice in anatomy, and images of the "meandering" artery were analyzed with NIH Image. The extent of "meandering" was expressed mainly as the ratio of the total length of the blood vessel to the distance between the starting point and the end point of meandering. The results showed that there was a significant difference in the extent of meandering between superior posterior and medial posterior branches of superior laryngeal artery. These arteries, which were distributed in the arytenoid region, were found to be of primary importance in partial laryngectomy and partial reconstruction of the larynx.

Anatomical study of the coexistence of the postaortic left brachiocephalic vein with the postaortic left renal vein with a review of the literature.

In a student course of gross anatomy dissection at Kanagawa Dental University in 2009, we found an extremely rare case of the coexistence of the postaortic left brachiocephalic vein with the postaortic left renal vein of a 73-year-old Japanese male cadaver. The left brachiocephalic vein passes behind the ascending aorta and connects with the right brachiocephalic vein, and the left renal vein passes behind the abdominal aorta. These two anomalous cases mentioned above have been reported respectively. There have been few reports discussing coexistence of the postaortic left brachiocephalic vein with the postaortic left renal vein. We discuss the anatomical and embryological aspect of this anomaly with reference in the literature.

Morphological observation of the horseshoe kidney with circumaortic venous ring.

In a student course of gross anatomy dissection at Knagawa Dental College in 2010, we found an extremely rare case of the horseshoe kidney with circumaortic venous ring in a 43-year-old Japanese male cadaver. In this case, the kidney consisted of three parts: the original kidneys on both sides and an isthmus between them. The location of each kidney was lower than that of the normal kidney. The hili on both sides opened toward the ventral direction, and the ureters descended in front of the isthmus and entered the bladder normally. This horseshoe kidney had original left and right renal arteries that branched from the abdominal aorta. There were also two surplus arteries. There were three renal veins on the left side, and these renal veins formed the circumaortic venous ring. The anatomical and embryological significance of this anomaly and its associated vascular system are discussed. The anatomy and etiology of these anomalous structures are discussed with references in the literature.