Embryonic development and cranial ossification of the Japanese Aodaisho, Elaphe climacophora (Serpentes: Colubridae): with special reference to the prootic bone and auditory evolution in snakes.

Snakes show remarkably deviated "body plan" from other squamate reptiles. In addition to limb loss, they have accomplished enormous anatomical specialization of the skull associated with the pit organs and the reduction of the tympanic membranes and auditory canals in the outer ears. Despite being the most diverse group of snakes, our knowledge of the embryonic staging for organogenesis and cranial ossification has been minimal for Colubridae. Therefore, in the present observation, we provide the first embryonic description of the Japanese rat snake Elaphe climacophora. We based our study on the Standard Event System (SES) for external anatomical characters and on a description of the cranial ossification during post-ovipositional development. We further estimated the relative ossification timing of each cranial bony element and compared it with that of selected other snakes, lizards, turtles, and crocodilians. The present study shows that the relative ossification timing of the palatine and pterygoid bones is relatively early in squamates when compared to other reptiles, implying the developmental integration as the palate-pterygoid complex in this clade and functional demands for the unique feeding adaptation to swallow large prey with the help of their large palatine and pterygoid teeth. Furthermore, unlike in species with pit organs, the prootic bone of Ela. climacophora is expanded to provide articulation with the supratemporal, thereby contributing to the hearing system by detecting substrate vibration. We also demonstrate that the relative timing of the prootic ossification is significantly accelerated in colubrids compared to snakes with pit organs. Our finding suggests that the temporal changes of the prootic ossification underpin the evolution of the perception of the ground-bourne sound signals among snakes.

The key to success in blocking lateral cutaneous branches with re-modified thoracoabdominal nerves block through perichondrial approach: a newly discovered space between the endothoracic fascia, diaphragm, and costodiaphragmatic recess.

PURPOSE: This study aimed to determine whether the administration of a modified thoracoabdominal nerves block through perichondrial approach (M-TAPA) could result in the blockade of the lateral cutaneous branches. This study focused on a newly discovered anatomical space/plane adjacent to the M-TAPA plane, which we termed "space between the endothoracic fascia, diaphragm, and costodiaphragmatic recess: SEDIC." METHODS: Thirteen sides of nine formalin-embalmed cadavers were macroscopically dissected to investigate the anatomical spaces related to the effects of M-TAPA. Furthermore, ten adult volunteers were administered 20 mL of 0.2% ropivacaine into the abdominal plane (corresponding to the M-TAPA plane) and the SEDIC, and a pinprick test was performed 1 h after the injection. RESULTS: Cadaver macrodissection revealed the presence of the SEDIC adjacent to the M-TAPA plane. The SEDIC was completely spatially isolated from the M-TAPA plane by the presence of costal cartilage and/or tendinous structures. In the volunteer study, the administration of local anesthetics into the SEDIC effectively blocked the lateral cutaneous branches of T8-T12, in addition to the anterior branches. CONCLUSION: Our study revealed the presence of the SEDIC adjacent to the M-TAPA plane. Administration of local anesthetics into the SEDIC, named re-modified TAPA, may have the potential to enhance the analgesic effect in the abdominal region.

The three layered structure of orbicularis oris and buccinator complex with partial connection at the modiolus and partial direct continuation.

PURPOSE: This study aimed to clarify the structural arrangement of the orbicularis oris (OOr), the buccinator, and the other perioral muscles around the modiolus. METHODS: The perioral muscles in seventeen cadavers fixed with formalin were dissected in situ and/or in isolated muscle specimens, and their layers were reconstructed schematically upon pantomographic view of the skeleton to evaluate their actions. RESULTS: The buccinator was composed of three parts including upper and lower oblique parts in its superficial layer and a middle transverse part in its deep layer. The superior and inferior OOr were composed of an inner marginal part (IM) and an outer labial part (OL) in each. The perioral muscles as a whole were arranged in three layers. The first layer consisted of the depressor anguli oris and the OL of superior OOr connected at the modiolus in a vertical direction. The second layer consisted of the upper and inner oblique part of buccinator and a part of the OL of inferior OOr connected at the modiolus in a horizontal direction. The third layer contained the middle transverse part of buccinator continuous with the IM of both OOr and a part of the OL of inferior OOr without connection to the modiolus. CONCLUSIONS: The different arrangement of the three layers of perioral muscles around the modiolus could serve as a good basis to predict the actions of the individual perioral muscles on the movement of lips in open/close of the oral fissure and widening/narrowing of the lip width.

Remote cadaveric minimally invasive surgical training.

Objective: The aim of the study is to discuss the efficacy of live vs. remote cadaver surgical training (CST) for minimally invasive surgery (MIS). Methods: A cohort of 30 interns in their first and second years of training were divided into three groups: live observers (n = 12), live participants (n = 6), and remote observers: (n = 12). The interns had the opportunity to either observe or actively participate in two different surgical procedures, namely, laparoscopic lower anterior resection, performed by a colorectal surgical team, and laparoscopic fundoplication, performed by a pediatric surgical team. The procedures were conducted either at a base center or at a remote center affiliated with the institute. Some of the interns interacted directly with the surgical teams at the base center, and others interacted indirectly with the surgical teams from the remote center. All interns were administered questionnaires before and after completion of the CST in order to assess their understanding of various aspects related to the operating room layout/instruments (called "design"), accessing the surgical field (called "field"), understanding of anatomic relations (called "anatomy"), their skill of dissection (called "dissection"), ability to resolve procedural/technical problems (called "troubleshooting"), and their skill in planning surgery (called "planning") according to their confidence to operate using the following scale: 1 = not confident to operate independently; 4 = confident to operate with a more senior trainee; 7 = confident to operate with a peer; and 10 = confident to operate with a less experienced trainee. A p < 0.05 was considered statistically significant. Results: All scores improved after CST at both the base and remote centers. The following significant increases were observed: for remote observers: "field" (2.67→4.92; p < .01), "anatomy" (3.58→5.75; p < .01), "dissection" (3.08→4.33; p = .01), and "planning" (3.08→4.33; p < .01); for live observers: "design" (3.75→6.17; p < .01), "field" (2.83→5.17; p < .01), "anatomy" (3.67→5.58; p < .01), "dissection" (3.17→4.58; p < .01), "troubleshooting" (2.33→3.67; p < .01), and "planning" (2.92→4.25; p < .01); and for live participants: "design" (3.83→6.33; p = .02), "field" (2.83→6.83; p < .01), "anatomy" (3.67→5.67; p < .01), "dissection" (2.83→6.17; p < .01), "troubleshooting" (2.17→4.17; p < .01), and "planning" (2.83→4.67; p < .01). Understanding of "design" improved significantly after CST in live observers compared with remote observers (p < .01). Understanding of "field and "dissection" improved significantly after CST in live participants compared with live observers (p = .01, p = .03, respectively). Out of the 12 remote observers, 10 participants (83.3%) reported that interacting with surgical teams was easy because they were not on-site. Conclusions: Although all the responses were subjective and the respondents were aware that observation was inferior to hands-on experience, the results from both centers were equivalent, suggesting that remote learning could potentially be viable when resources are limited.

Unique morphological architecture of the hamstring muscles and its functional relevance revealed by analysis of isolated muscle specimens and quantification of structural parameters.

The structural and functional differences of individual hamstrings have not been sufficiently evaluated. This study aimed to clarify the morphological architecture of the hamstrings including the superficial tendons in detail using isolated muscle specimens, together with quantification of structural parameters of the muscle. Sixteen lower limbs of human cadavers were used in this study. The semimembranosus (SM), semitendinosus (ST), biceps femoris long head (BFlh), and biceps femoris short head (BFsh) were dissected from cadavers to prepare isolated muscle specimens. Structural parameters, including muscle volume, muscle length, fiber length, sarcomere length, pennation angle, and physiological cross-sectional area (PCSA) were measured. In addition, the proximal and distal attachment areas of the muscle fibers were measured, and the proximal/distal area ratio was calculated. The SM, ST, and BFlh were spindle-shaped with the superficial origin and insertion tendons on the muscle surface, and the BFsh was quadrate with direct attachment to the skeleton and BFlh tendon. The muscle architecture was pennate in the four muscles. The four hamstrings possessed either of two types of structural parameters, one with shorter fiber length and larger PCSA, as in the SM and BFlh, and the other with longer fiber length and smaller PCSA, as in the ST and BFsh. Sarcomere length was unique in each of the four hamstrings, and thus the fiber length was suitably normalized using the average sarcomere length for each, instead of uniform length of 2.7 µm. The proximal/distal area ratio was even in the SM, large in the ST, and small in the BFsh and BFlh. This study clarified that the superficial origin and insertion tendons are critical determinants of the unique internal structure and structural parameters representing the functional properties of the hamstring muscles.

A Single Administration of Progesterone during the Neonatal Period Shows No Structural Changes in Male Reproductive Tracts in Mice.

The concentration of female-dominant steroid hormones, such as progesterone and estrogen, drops after birth in neonates. We have reported that neonatal estrogen treatment results in inflammation in the epididymis after puberty in male mice. Our recent study discovered that progesterone receptor was specifically expressed in efferent ducts just before birth in male mice. Therefore, this study aimed to reveal the impact of neonatal progesterone administration on the efferent ducts after puberty. Progesterone was subcutaneously administered to neonatal mice on their birthday in three groups: high-dose (200 mg/kg), low-dose (8 mg/kg), and control (cottonseed oil). Their testis and epididymis were collected at 12 weeks old. Semi-serial paraffin sections of these tissues were prepared and evaluated through PAS-hematoxylin staining. Efferent ducts were reconstructed into a three-dimensional structure, and their length and volume were analyzed. Spermatogenesis in the testis and epithelium of the tracts appeared normal, even in individuals administered with progesterone. There were no significant differences in the length and volume of the efferent ducts among the three groups. This study suggests that progesterone treatment in neonatal mice does not cause any structural changes in the male reproductive tracts at puberty, unlike the neonatal estrogen treatment.

Novel external oblique muscle plane block for blockade of the lateral abdominal wall: a pilot study on volunteers.

PURPOSE: No reports have described techniques to efficiently anesthetize the lateral cutaneous branches of the entire abdomen. The aim of this study was to investigate an effective procedure for blocking the lateral cutaneous branches in the abdominal region. We sought to describe the sensory distribution of the previously described thoracoabdominal nerve block through perichondrial approach (TAPA) and the novel costal and lateral external oblique muscle plane (EXOP) blocks in healthy volunteers. METHODS: This was a proof-of-concept pilot study that comprised ten volunteers with an American Society of Anesthesiologists Physical Status I. The participants underwent modified TAPA (M-TAPA), injection 2 of TAPA (injection into the anterior aspect of the 10th costal cartilage: I2-TAPA), costal EXOP, and lateral EXOP blocks with injection of 20 mL of ropivacaine 0.2% for each block. A pinprick test was performed one hour after injection and repeated at 30-min intervals until the effect of the nerve block disappeared. RESULTS: The M-TAPA injection anesthetized the anterior branches from T6/7 to T11/12, whereas the I2-TAPA injection had no effect. Costal and lateral EXOP injections anesthetized the lateral cutaneous branches of T7-10 and T11-12, respectively. CONCLUSION: The results of this pilot study in ten healthy volunteers indicate that novel EXOP blocks involving local anesthetic injection superficial to the external oblique muscle efficiently anesthetize the lateral cutaneous branches of the thoracoabdominal nerves. Our study shows that it may be anatomically plausible for the combined use of these blocks to anesthetize the entire abdominal wall.

RéSUMé: OBJECTIF: Aucune présentation de cas n'a décrit de techniques permettant l'anesthésie efficace des branches cutanées latérales de tout l'abdomen. L'objectif de cette étude était d'évaluer une procédure efficace pour bloquer les branches cutanées latérales de la région abdominale. Nous avons cherché à décrire la distribution sensorielle du bloc nerveux thoraco-abdominal par approche périchondrale (TAPA), décrit précédemment, et des nouveaux blocs du plan musculaire oblique externe (EXOP) costal et latéral réalisés chez des volontaires sains. MéTHODE: Il s'agissait d'une étude pilote de preuve de concept qui comprenait dix volontaires avec un statut physique I selon l'American Society of Anesthesiologists. Les participants ont bénéficié d'un bloc TAPA modifié (M-TAPA), de l'injection 2 d'un bloc TAPA (injection dans l'aspect antérieur du 10e cartilage costal : I2-TAPA), d'un bloc EXOP costal et d'un bloc EXOP latéral avec injection de 20 mL de ropivacaïne 0,2 % pour chaque bloc. Un test cutané par piqûre d'épingle a été réalisé une heure après l'injection et répété à des intervalles de 30 minutes jusqu'à ce que l'effet du bloc nerveux disparaisse. RéSULTATS: L'injection de M-TAPA a anesthésié les branches antérieures de T6/7 à T11/12, tandis que l'injection d'I2-TAPA n'a eu aucun effet. Les injections costales et latérales d'EXOP ont anesthésié les branches cutanées latérales de T7­10 et T11­12, respectivement. CONCLUSION: Les résultats de cette étude pilote chez dix volontaires sains indiquent que les nouveaux blocs EXOP avec une injection superficielle d'anesthésique local au muscle oblique externe anesthésient efficacement les branches cutanées latérales des nerfs thoraco-abdominaux. Notre étude montre qu'il peut être anatomiquement plausible de combiner ces blocs pour anesthésier toute la paroi abdominale.

LRBA is essential for urinary concentration and body water homeostasis.

Protein kinase A (PKA) directly phosphorylates aquaporin-2 (AQP2) water channels in renal collecting ducts to reabsorb water from urine for the maintenance of systemic water homeostasis. More than 50 functionally distinct PKA-anchoring proteins (AKAPs) respectively create compartmentalized PKA signaling to determine the substrate specificity of PKA. Identification of an AKAP responsible for AQP2 phosphorylation is an essential step toward elucidating the molecular mechanisms of urinary concentration. PKA activation by several compounds is a novel screening strategy to uncover PKA substrates whose phosphorylation levels were nearly perfectly correlated with that of AQP2. The leading candidate in this assay proved to be an AKAP termed lipopolysaccharide-responsive and beige-like anchor protein (LRBA). We found that LRBA colocalized with AQP2 in vivo, and Lrba knockout mice displayed a polyuric phenotype with severely impaired AQP2 phosphorylation. Most of the PKA substrates other than AQP2 were adequately phosphorylated by PKA in the absence of LRBA, demonstrating that LRBA-anchored PKA preferentially phosphorylated AQP2 in renal collecting ducts. Furthermore, the LRBA-PKA interaction, rather than other AKAP-PKA interactions, was robustly dissociated by PKA activation. AKAP-PKA interaction inhibitors have attracted attention for their ability to directly phosphorylate AQP2. Therefore, the LRBA-PKA interaction is a promising drug target for the development of anti-aquaretics.

Relationship between the lumbosacral plexus deviation and 12th rib length in Japanese macaques (Macaca fuscata).

The relationship between the lumbosacral plexus (LSP) origin and the 12th rib length was recently determined in humans; cranial and caudal deviations of the plexus origin are related to shortening and elongation of the 12th rib, respectively. However, it remains unclear whether such anatomical correlations are also observed in non-human mammals. To address this issue, in the present study, we evaluated the LSP origin and the 12th rib length in Japanese macaques (Macaca fuscata). In typical cases, the femoral and obturator nerves were derived from both the 4th and 5th lumbar nerves, and the lumbosacral trunk was from the 5th to 7th lumbar nerves. Some of the LSPs exhibited a caudal deviation of their origins; the femoral and obturator nerves were also derived from the 6th lumbar nerve, in addition to the 4th and 5th lumbar nerves; the lumbosacral trunk lost the 5th lumbar nerve origin and arose from the 6th and 7th lumbar nerves. Individuals with the caudal deviation of LSP origin exhibited significant elongation of the 12th ribs, in comparison with individuals with the typical plexus. The present findings indicate that the caudal deviation of LSP origin was correlated to the 12th rib elongation in Japanese macaques, similar to humans. As a future studies, we need to clarify which mammalian groups exhibit such correlation between the deviation of the LSP origin and the lowest rib length, and further to provide evolutionary implications of this correlation.

Calpain inhibitor suppresses both extracellular vesicle-mediated secretion of miRNAs and egg production from paired adults of Schistosoma japonicum.

Extracellular vesicles (EVs) have been reported to be secreted from Schistosoma japonicum at all developmental stages. However, the reproduction and communication mechanisms between the paired adults through the EVs in dioecious Trematoda have not been reported. In this study, EVs containing many exosome-like vesicles and microvesicles were observed in the supernatants of paired adults cultured in vitro, and abundant selected miRNAs were contained in them. In particular, the female-specific miR-bantam was present only in vesicles and was hardly secreted outside the vesicles. In this study, we found that male-female pairing induced secretion of miR-3479 and miR-bantam in EVs, but not of male-specific miR-61. Furthermore, ingestion of mouse erythrocytes also increased the production of miRNAs in paired adult and single female worms. Vesicles were found in the tegument of females treated with erythrocytes under electron microscopy. After the paired worms were treated with several inhibitors against the secretion of EVs, only calpain inhibitor (calpeptin) significantly reduced the amount of miRNA in EVs. Furthermore, the worms treated with only calpeptin inhibited egg production in vitro. Together, these results indicate that qualitative miRNA production through EVs regulated by calpain plays a role in egg production in S. japonicum.

Anatomical position of the corona mortis relative to the anteroposterior and inlet views.

PURPOSE: Although pubic ramus fractures are common in the elderly, resultant hemodynamic instability is a rare complication. The corona mortis, a vascular anastomosis between the obturator vessels and the external iliac vessels in the retropubic space, is occasionally damaged by fractures of the pubic ramus, causing significant hemorrhage. The purpose of this study was to evaluate the incidence and anatomical position of the corona mortis on the anteroposterior and inlet views. METHODS: Sixty-one cadavers (122 hemipelvizes) were dissected and the incidence of the corona mortis was evaluated. Photographs were then taken simulating anteroposterior and inlet radiographs, and labeled as the anteroposterior and inlet views. The distance from the pubic symphysis to the corona mortis was measured on each of the two views. RESULTS: The corona mortis was present in 76.1% of hemipelvizes. The corona mortis traverses along the periosteum of the dorsal surface of the pubis. The incidence of arterial corona mortis was 28.3% and that of venous corona mortis was 76.1%. The distance from the superior margin of the symphysis pubis to the corona mortis measured 47.7 ± 9.9 (45.9-49.6) mm on the anteroposterior view, and 59.4 ± 9.2 (57.3-61.5) mm on the inlet view. CONCLUSIONS: In order to predict possible hemodynamic instability of the corona mortis following pubic ramus fractures, it is of clinical significance to precisely establish the anatomical position of the corona mortis on the anteroposterior and inlet views.

Cadaver Training for Minimally Invasive Pediatric Surgery: A Preliminary Report.

Aim: To report the value of adult cadavers for training in minimally invasive surgical (MIS) techniques for pediatric surgery (PS). Materials and Methods: Three teams, each consisting of a board-certified consultant pediatric surgeon (CS), a senior trainee (ST), and a junior trainee (JT), attended a cadaver surgical training (CST) course involving five procedures: thoracoscopic esophagoesophagostomy (TEE), thoracoscopic right lower lobectomy (TRL), laparoscopic fundoplication (LFN), laparoscopic hepaticoduodenostomy (LHD), and laparoscopic ureteroureterostomy (LUU). The same teams also performed LFN on live pigs. Attendees (3 CSs, 3 STs, and 3 JTs) were administered a questionnaire to rate their CST experience according to five criteria (tissue texture, organ size, operative field, "feel," and anatomic relationships) using a 4-point scale with 0 being the worst response. Scores were averaged per procedure per attendee groups and compared. LFN was also compared between a cadaver and a pig. Results: End-point (1): For LFN, cadaver scores were significantly higher than pig scores for anatomic relationships (P = .0001), operative field (P = .0053), and organ size (P = .0481). End-point (2): TRL and LFN were ranked together as being most realistic, followed by TEE and LUU, then LHD. End-point (3): Anatomic relationships and operative field consistently scored highly for all attendee groups. End-point (4): CSs and STs tended to award higher scores than JTs although differences were not statistically significant. Conclusions: CST is a valuable opportunity for PS trainees to experience highly realistic training in minimally invasive surgery. Pig training was inferior. IRB Number: 2019173.

Three-Dimensional Architecture of Glomerular Endothelial Cells Revealed by FIB-SEM Tomography.

Focused-ion beam-scanning electron microscopic (FIB-SEM) tomography enables easier acquisition of a series of ultrastructural, sectional images directly from resin-embedded biological samples. In this study, to clarify the three-dimensional (3D) architecture of glomerular endothelial cells (GEnCs) in adult rats, we manually extracted GEnCs from serial FIB-SEM images and reconstructed them on an Amira reconstruction software. The luminal and basal surface structures were clearly visualized in the reconstructed GEnCs, although only the luminal surface structures could be observed by conventional SEM. The luminal surface visualized via the reconstructed GEnCs was quite similar to that observed through conventional SEM, indicating that 3D reconstruction could be performed with high accuracy. Thus, we successfully described the 3D architecture of normal GEnCs in adult rats more clearly and precisely than ever before. The GEnCs were found to consist of three major subcellular compartments, namely, the cell body, cytoplasmic ridges, and sieve plates, in addition to two associated subcellular compartments, namely, the globular protrusions and reticular porous structures. Furthermore, most individual GEnCs made up a "seamless" tubular shape, and some of them formed an autocellular junction to make up a tubular shape. FIB-SEM tomography with reconstruction is a powerful approach to better understand the 3D architecture of GEnCs. Moreover, the morphological information revealed in this study will be valuable for the 3D pathologic evaluation of GEnCs in animal and human glomerular diseases and the structural analysis of developmental processes in the glomerular capillary system.

Anatomic characterization of the tibial and fibular nutrient arteries in humans.

The location of nutrient foramina has been extensively studied in long bones; however, accurate information on the origin and extra-osseous course of the nutrient artery remains clearly defined in some long bones, although it is crucial to protect the nutrient arteries during operative procedures. In this study, we elucidated the origin and extra-osseous course of tibial and fibular nutrient arteries based on the 54 cadaveric legs. The tibial nutrient artery typically arose from the posterior tibial artery. Some of the tibial nutrient arteries arose from the anterior tibial, popliteal, and fibular arteries. The tibial nutrient artery arose from these parent arteries as a long descending branch. It penetrated the most proximal portion of the tibialis posterior or flexor digitorum longus to enter the tibial nutrient foramen. The fibular nutrient artery arose from the fibular artery as a short descending branch in all the cases. The fibular nutrient artery penetrated the flexor hallucis longus to enter the fibular nutrient foramen. Our present and previous findings provide new insight into the anatomical characteristics for the nutrient arteries in the long bones of upper and lower extremities. Namely, the nutrient arteries of the long bones go away from the elbow or knee to enter the nutrient foramina.

Anatomical study of the soleus: Application to improved imaging diagnoses.

INTRODUCTION: Strains of the soleus are widely found both in amateur and professional athletes. For their accurate regional diagnoses, understanding the anatomy of the spatial relationship between muscular fibers and tendinous structures is important because their interfaces are susceptible sites to muscle strains. Therefore, this study evaluated the precise architecture of the soleus. MATERIALS AND METHODS: We evaluated the precise anatomical architecture of the soleus in 87 formaldehyde-fixed soleus muscles. To calculate mean relative physiological cross-sectional area of each muscular fiber compartment, we measured the fiber length, volume, and pennation angle in isolated compartments. RESULTS: The posterior soleus surface was covered by a broad aponeurotic posterior insertion tendon (PIT), which continued inferiorly to the insertion tendon. The anterior surface had three aponeurotic origin tendons, lateral origin tendon (LOT), medial origin tendon (MOT), and tendinous arch, which were arranged along the soleus margins. The anterior bipennate muscle portion (ABP), surrounded by the three origin structures, terminated as the sagittal insertion tendon (SIT), which continued inferiorly to PIT. The posterior main muscle portion behind LOT and MOT was separated into lateral and medial portions by the SIT. The soleus thus possessed a broad musculotendinous junction. Furthermore, ABP exhibited wide structural diversity in shape and size: in extreme cases, it was duplicated or absent. CONCLUSION: Systematic anatomical descriptions of the soleus will be useful for accurate regional diagnosis of its strains with magnetic resonance imaging and ultrasonography.

MAGI-2 orchestrates the localization of backbone proteins in the slit diaphragm of podocytes.

Podocytes are highly specialized cells within the glomerulus that are essential for ultrafiltration. The slit diaphragm between the foot processes of podocytes functions as a final filtration barrier to prevent serum protein leakage into urine. The slit-diaphragm consists mainly of Nephrin and Neph1, and localization of these backbone proteins is essential to maintaining the integrity of the glomerular filtration barrier. However, the mechanisms that regulate the localization of these backbone proteins have remained elusive. Here, we focused on the role of membrane-associated guanylate kinase inverted 2 (MAGI-2) in order to investigate mechanisms that orchestrate localization of slit-diaphragm backbone proteins. MAGI-2 downregulation coincided with a reduced expression of slit-diaphragm backbone proteins in human kidneys glomerular disease such as focal segmental glomerulosclerosis or IgA nephropathy. Podocyte-specific deficiency of MAGI-2 in mice abrogated localization of Nephrin and Neph1 independently of other scaffold proteins. Although a deficiency of zonula occuldens-1 downregulated the endogenous Neph1 expression, MAGI-2 recovered Neph1 expression at the cellular edge in cultured podocytes. Additionally, overexpression of MAGI-2 preserved Nephrin localization to intercellular junctions. Co-immunoprecipitation and pull-down assays also revealed the importance of the PDZ domains of MAGI-2 for the interaction between MAGI-2 and slit diaphragm backbone proteins in podocytes. Thus, localization and stabilization of Nephrin and Neph1 in intercellular junctions is regulated mainly via the PDZ domains of MAGI-2 together with other slit-diaphragm scaffold proteins. Hence, these findings may elucidate a mechanism by which the backbone proteins are maintained.

Nephrocytes are part of the spectrum of filtration epithelial diversity.

The excretory system produces urine by ultrafiltration via a filtration epithelium. Podocytes are widely found as filtration epithelial cells in eucoelomates. In some animal taxa, including insects and crustaceans, nephrocytes serve to separate toxic substances from the body fluid, in addition to podocytes. Drosophila nephrocytes have been recently utilized as a model system to study podocyte function and disease. However, functionality and cellular architecture are strikingly different between Drosophila nephrocytes and eucoelomate podocytes, and the phylogenetic relationship between these cells remains enigmatic. In this study, using focused-ion beam-scanning electron microscopy (FIB-SEM) tomography, we revealed three-dimensional architecture of decapod nephrocytes with unprecedented accuracy-they filled an enormous gap, which can be called "missing link," in the evolutionary diversity of podocytes and nephrocytes. Thus, we concluded that nephrocytes are part of the spectrum of filtration epithelial diversity in animal phylogeny.

Anatomic Analysis of the Attachment of the Posteroinferior Labrum and Capsule to the Glenoid: A Cadaveric Study.

PURPOSE: To measure the height of the posteroinferior glenohumeral ligament (PIGHL) attachment to the labrum and the depth of the posteroinferior labrum to the glenoid, macroscopically, and to investigate the morphology of the attachment of the posteroinferior labrum to the glenoid, histologically. METHODS: Fifty cadaveric shoulders without exposed subchondral bone on the glenoid and detached posterior labrum were used. We examined the frequency of the heights of the PIGHL attachments to the labrum and the length of the labral attachment on the glenoid rim at the 7, 8, 9, and 10 o'clock positions, macroscopically. According to morphology of the histological labral attachments, it was divided into 3 groups. Labra attached on the articular surface and the glenoid neck were defined as the SN type, while labra attached only to the glenoid neck constituted labra attached to the bone and side of the articular cartilage (Nc type) and labra attached only to bone (Nb type). RESULTS: The PIGHL attached from 7 o'clock to 9 o'clock in 48 shoulders (96%). The mean labral attachment at the 7 o'clock position was 6.3 ± 1.0 mm (range, 4.6-9.4 mm), which was significantly longer than at the other positions (P < .05). Histologically, the frequency of SN type attachment was 49 (98%) shoulders at the 7 o'clock position. CONCLUSIONS: The PIGHL attached between 7 and 9 o'clock in 96% of the shoulders. In 98% of the shoulders, the labrum did not attach to the articular surface, but attached to both the articular cartilage and the bone of the glenoid neck at 7 o'clock. CLINICAL RELEVANCE: The posteroinferior labrum should be repaired widely at the 7 o'clock position and not on the articular surface because the labrum attached anatomically to the glenoid neck.