Anatomy of muscle connections in the male urethra and anorectal canal

OBJECTIVES

To elucidate the male urethral muscular structure and its relationship with the anorectal canal muscles, as establishing an anatomical foundation for urethral function will contribute to the prevention, diagnosis, and treatment of urinary incontinence.

METHODS

Eight male cadavers were used. Using a multifaceted approach, we performed macroscopic anatomical examination, histological analysis of wide-range serial sectioning and immunostaining, and three-dimensional (3D) reconstruction from histological sections. In the macroscopic anatomical examination, pelvic halves were meticulously dissected in layers from the medial aspect. In the histological analysis, the tissue, including the urethra and anorectal canal, was serially sectioned in the horizontal plane. The muscular structures were reconstructed and visualised in 3D.

RESULTS

The membranous portion of the urethra had three muscle layers: the longitudinal and circular muscles (smooth muscle) and the external urethral sphincter (skeletal muscle). The circular muscle was connected posteriorly to the longitudinal rectal muscle. The external urethral sphincter had a horseshoe shape, with its posterior ends continuing to the external anal sphincter, forming a 3D ring-like sphincter.

CONCLUSION

This study revealed skeletal and smooth muscle connections between the male urethra and anorectal canal, enabling urethral compression and closure. These anatomical muscle connections suggest a functional linkage between them.

Retroperitoneal fasciae as barriers for nerve and arterial passages connecting the retroperitoneal region to the peritoneal organs

The fascia of the pancreatic head is referred to as the retropancreatic fascia of Treitz, and that of the body and tail of the pancreas is named the retropancreatic fascia of Toldt. However, the spatial relationship between the nerves, fascia, and the distribution of the fascia on the dorsal side of the pancreas remains unclear. Therefore, this study aimed to explore the distribution of these fasciae and elucidate the spatial relationship between the nerves and arteries connecting the retroperitoneal space and the peritoneal organs by studying eight cadavers using macroscopic anatomical examination, wide-range serial sectioning, and three-dimensional reconstruction. The fasciae of Treitz and Toldt converge caudally to the root of the superior mesenteric artery (SMA), forming a narrower gap around the roots of the celiac trunk and SMA than in the celiac plexus. The fasciae eventually get closer to each other, and the boundary between them becomes obscured, providing coverage to the anterior surface of the aorta between the SMA and the inferior mesenteric artery. The celiac plexus does not penetrate the fascia but converges before spreading into the pancreas. Similarly, the arteries pass through this gap in the fasciae. Our findings suggest that the retroperitoneal space and peritoneal organs are connected through a narrow no-fascia area, with the distribution of the fascia relating to nervous and vascular pathways. Our findings reveal that the distribution of the avascular plane may provide a crucial anatomical foundation for abdominal digestive organ surgery by reducing bleeding volume and determining the dissection region.

Significant relationship between musculoaponeurotic attachment of the abdominal and thigh adductor muscles to the pubis: implications for the diagnosis of groin pain

Groin pain is prevalent in orthopedic and sports medicine, causing reduced mobility and limiting sports activity. To effectively manage groin pain, understanding the detailed anatomy of supporting muscles is crucial. This study aimed to investigate the musculoaponeurotic attachments on the pubis and the relationship among intramuscular aponeuroses of abdominal and thigh adductor musculatures. Macroscopic analyses were performed in 10 pelvic halves. The bone morphology of the pubis was assessed in two pelvic halves using microcomputed tomography. Histological investigations were conducted in two pelvic halves. The external oblique aponeurosis extended to the adductor longus aponeurosis, forming conjoined aponeurosis, which attached to a small impression distal to the pubic crest. The gracilis aponeurosis merges with the adductor brevis aponeurosis and is attached to the proximal part of the inferior pubic ramus. The rectus abdominis and pyramidalis aponeuroses were attached to the pubic crest and intermingled with the gracilis-adductor brevis aponeurosis, forming bilateral conjoined aponeurosis, which attached to a broad area covering the anteroinferior surface of the pubis. Histologically, these two areas of conjoined aponeuroses were attached to the pubis via the fibrocartilage enthesis. Microcomputed tomography revealed two distinctive bone morphologies, a small impression and an elongated osseous prominence on pubis, corresponded to the two areas of conjoined aponeuroses. This study demonstrated close relationships between the aponeurotic attachment of the external oblique and adductor longus, and between the rectus abdominis, pyramidalis, gracilis, and adductor brevis. The findings of aponeurotic complexes would aid in diagnostic and surgical approaches for athletic groin pain.

Twisted orientation of the muscle bundles in the levator ani functional parts in women: Implications for pelvic floor support mechanism

This study presents a comprehensive investigation of the anatomical features of the levator ani muscle. The levator ani is a critical component of the pelvic floor; however, its intricate anatomy and functionality are poorly understood. Understanding the precise anatomy of the levator ani is crucial for the accurate diagnosis and effective treatment of pelvic floor disorders. Previous studies have been limited by the lack of comprehensive three-dimensional analyses; to overcome this limitation, we analysed the levator ani muscle using a novel 3D digitised muscle-mapping approach based on layer-by-layer dissection. From this examination, we determined that the levator ani consists of overlapping muscle bundles with varying orientations, particularly in the anteroinferior portion. Our findings revealed distinct muscle bundles directly attached to the rectum (LA-re) and twisted muscle slings surrounding the anterior (LA-a) and posterior (LA-p) aspects of the rectum, which are considered functional parts of the levator ani. These results suggest that these specific muscle bundles of the levator ani are primarily responsible for functional performance. The levator ani plays a crucial role in rectal elevation, lifting the centre of the perineum and narrowing the levator hiatus. The comprehensive anatomical information provided by our study will enhance diagnosis accuracy and facilitate the development of targeted treatment strategies for pelvic floor disorders in clinical practice.

Morphometric Analysis of the Tibial Attachment Shape of the Anterior Cruciate Ligament and Its Relationship With the Location of the Anterior Horn of the Lateral Meniscus

BACKGROUND

The success of anterior cruciate ligament (ACL) reconstruction relies on the accurate replication of the native ACL anatomy, including attachment shapes. The tibial attachment of the ACL exhibits significant shape variations with elliptical, C, and triangular shapes, highlighting the need for objective classification methods and additional information to identify individual anatomic variations.

HYPOTHESIS

The location of the attachment of the anterior horn of the lateral meniscus (AHLM) may determine the shape of the ACL attachment.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

The study used 25 knees from 17 Japanese cadavers for macroscopic anatomic examination and quantitative analysis. The shape of the ACL attachment was quantified using principal component analysis with elliptical Fourier descriptors, whereas the AHLM location was quantified by measuring its mediolateral and anteroposterior positions on the superior surface of the tibia. Reliability was assessed statistically.

RESULTS

The shape of the tibial attachment of the ACL varied among individuals and was classified as elliptical, C-shaped, or triangular. Scatterplots of the principal components of the ACL attachment shape showed overlapping regions of elliptical, C-shaped, and triangular ACL attachments, indicating that a C-shaped attachment is intermediate between elliptical and triangular attachments. The location of the AHLM attachment also varied, with areas in the anterolateral, anteromedial, or posteromedial region. The ACL shape and AHLM location were related, with elliptical, C-shaped, and triangular ACL attachments corresponding to anterolateral, anteromedial, and posteromedial AHLM attachments, respectively.

CONCLUSION

The AHLM attachment location influences the shape of the ACL attachment. Information on the location of the AHLM attachment can aid in predicting the shape of the ACL attachment during ACL reconstruction, potentially improving footprint coverage.

Denonvilliers' fascia as a potential nerve-course marker for the female urinary bladder

OBJECTIVES

This study investigated the relationship between Denonvilliers' fascia (DF) and the pelvic plexus branches in women and explored the possibility of using the DF as a positional marker in nerve-sparing radical hysterectomy (RH).

METHODS

This study included eight female cadavers. The DF, its lateral border, and the pelvic autonomic nerves running lateral to the DF were dissected and examined. The pelvis was cut into two along the mid-sagittal line. The uterine artery, deep uterine veins, vesical veins, and nerve branches to the pelvic organs were carefully dissected.

RESULTS

The nerves ran sagitally, while the DF ran perpendicularly to them. The rectovaginal ligament was continuous with the DF, forming a single structure. The DF attached perpendicularly and seamlessly to the pelvic plexus. The pelvic plexus branches were classified into a ventral part branching to the bladder, uterus, and upper vagina and a dorsal part branching to the lower vagina and rectum as well as into four courses. Nerves were attached to the rectovaginal ligament and ran on its surface to the bladder ventral to the DF. The uterine branches split from the common trunk of these nerves. The most dorsal branch to the bladder primarily had a common trunk with the uterine branch, which is the most important and should be preserved in nerve-sparing Okabayashi RH.

CONCLUSION

The DF can be used as a marker for nerve course, particularly in one of the bladder branches running directly superior to the DF, which can be preserved in nerve-sparing Okabayashi RH.

Surgical anatomy of the dorsal pancreatic artery: Considering embryonic development

OBJECTIVES

The dorsal pancreatic artery (DPA) is a pancreatic branch with various anatomical variations. Previous studies mostly focused on the origin of the DPA, and its pathways and branching patterns have rarely been examined. The purpose of this study was to investigate the branching patterns and pathways of the DPA.

METHODS

This study included 110 patients who underwent computed tomography scans. We examined the pathways and branching patterns of the DPA.

RESULTS

The DPA was identified in 101 patients (92%), and originated from the splenic artery in 30 patients (31%), the common hepatic artery in 17 patients (17%), the celiac trunk in 10 patients (10%), the superior mesenteric artery in 27 patients (27%), the replaced right hepatic artery in 7 patients (7%), the inferior pancreaticoduodenal artery in 5 patients (5%), and other arteries in 3 patients (3%). Four distinct types of branches were identified as follows: the superior branch (32%), the inferior branch (86%), the right branch (80%), and the accessory middle colic artery (12%). Additionally, the arcs of Buhler and Riolan were observed in two patients each and their anastomotic vessels followed almost the same pathway as the DPA.

CONCLUSION

A number of variations of the DPA were observed with regard to its origin and branching pattern; however, the DPA and its branches always ran along the same pathway, as summarized in Fig. 4. The anatomical information gained from this study may contribute to performing safe pancreatic resections.

Histological study of the structural layers around the esophagus in the lower mediastinum

BACKGROUND

In Japan, the transhiatal approach, including lower mediastinal lymph node dissection, is widely performed for Siewert type II esophagogastric junction adenocarcinoma. This procedure is generally performed in a magnified view using laparoscopy or a robotic system, therefore, the microanatomy of the lower mediastinum is important. However, mediastinal microanatomy is still unclear and classification of lower mediastinal lymph nodes is not currently based on fascia or other microanatomical structures.

AIM

To clarify the fascia and layer structures of the lower mediastinum and classify the lower mediastinal tissue.

METHODS

We dissected the esophagus and surrounding organs en-bloc from seven cadavers fixed in 10% formalin. Organs and tissues were then cut at the level of the lower thoracic esophagus, embedded in paraffin, and serially sectioned. Tissue sections were stained with Hematoxylin-Eosin (all cadavers) and immunostained for the lymphatic endothelial marker D2-40 (three cadavers). We observed the periesophageal fasciae and layers, and defined lymph node boundaries based on the fasciae. Lymphatic vessels around the esophagus were observed on immunostained tissue sections.

RESULTS

We identified two fasciae, A and B. We then classified lower mediastinal tissue into three areas, paraesophageal, paraaortic, and intermediate, using these fasciae as boundaries. Lymph nodes were found to be present and were counted in each area. The dorsal part of the intermediate area was thicker on the caudal side than on the cranial side in all cadavers. On the dorsal side, no blood vessels penetrated the fasciae in six of the seven cadavers, whereas the proper esophageal artery penetrated fascia B in one cadaver. D2-40 immunostaining showed lymphatic vessel connections between the paraesophageal and intermediate areas on the lateral and ventral sides of the esophagus, but no lymphatic connection between areas on the dorsal side of the esophagus.

CONCLUSION

Histological studies identified two fasciae surrounding the esophagus in the lower mediastinum and the layers separated by these fasciae were used to classify the lower mediastinal tissues.

The Use of the Deep Brachial Artery as the Recipient Artery for Free Perforator Flap Transfer: An Anatomic Study and Clinical Applications

Background and Objectives: Soft tissue reconstruction after sarcoma ablation in the posterior aspect of the upper arm has been commonly addressed using the pedicled latissimus dorsi musculo-cutaneous flap. The use of a free flap for coverage of this region has not been reported in detail. The goal of this study was to characterize the anatomical configuration of the deep brachial artery in the posterior upper arm and assess its clinical utility as a recipient artery for free-flap transfers. Materials and Methods: In total, 18 upper arms from 9 cadavers were used for anatomical study to identify the deep brachial artery's origin and point of crossing the x-axis, which was set from the acromion to the medial epicondyle of the humerus. Measurements of the diameter were taken at each point. The anatomic findings of the deep brachial artery were employed clinically in the reconstruction of the posterior upper arm after sarcoma resection using free flaps in 6 patients. Results: The deep brachial artery was found in all specimens between the long head and the lateral head of the triceps brachii muscle, and it crossed the x-axis at an average distance of 13.2 ± 2.9 cm from the acromion, with an average diameter of 1.9 ± 0.49 mm. In all 6 clinical cases, the superficial circumflex iliac perforator flap was transferred to cover the defect. The average size of the recipient artery, the deep brachial artery, was 1.8 mm (range, from 1.2 to 2.0 mm). The average diameter of the pedicle artery, the superficial circumflex iliac artery, was 1.5 mm (range, from 1.2 to 1.8 mm). All flaps survived completely with no postoperative complications. Conclusions: The deep brachial artery can be a reliable recipient artery in free-flap transfers for posterior upper arm reconstruction, given its anatomical consistency and sufficient diameter.

Distribution of splenic artery lymph nodes and splenic hilar lymph nodes

BACKGROUND

Total gastrectomy with splenectomy is the standard treatment for advanced proximal gastric cancer with greater-curvature invasion. As an alternative to splenectomy, laparoscopic spleen-preserving splenic hilar lymph node (LN) dissection (SPSHLD) has been developed. With SPSHLD, the posterior splenic hilar LNs are left behind.

AIM

To clarify the distribution of splenic hilar (No. 10) and splenic artery (No. 11p and 11d) LNs and to verify the possibility of omitting posterior LN dissection in laparoscopic SPSHLD from an anatomical standpoint.

METHODS

Hematoxylin & eosin-stained specimens were prepared from six cadavers, and the distribution of LN No. 10, 11p, and 11d was evaluated. In addition, heatmaps were constructed and three-dimensional reconstructions were created to visualize the LN distribution for qualitative evaluation.

RESULTS

There was little difference in the number of No. 10 LNs between the anterior and posterior sides. For LN No. 11p and 11d, the anterior LNs were more numerous than the posterior LNs in all cases. The number of posterior LNs increased toward the hilar side. Heatmaps and three-dimensional reconstructions showed that LN No. 11p was more abundant in the superficial area, while LN No. 11d and 10 were more abundant in the deep intervascular area.

CONCLUSION

The number of posterior LNs increased toward the hilum and was not neglectable. Thus, surgeons should consider that some posterior No. 10 and No. 11d LNs may remain after SPSHLD.

Origin, course, and distribution of the posterior femoral cutaneous nerve and the spatial relationship among its branches

This study aimed to elucidate the origin, course, and distribution of the branches of the posterior femoral cutaneous nerve, considering the segmental and dorsoventral compositions of the sacral plexus, including the pudendal nerve. The buttocks and thighs of five cadavers were analyzed bilaterally. The branches emerged from the sacral plexus, which was divided dorsally to ventrally into the superior gluteal, inferior gluteal, common peroneal, tibial, and pudendal nerves. It descended lateral to the ischial tuberosity and comprised the thigh, gluteal, and perineal branches. As for the thigh and gluteal branches, the dorsoventral order of those originating from the sacral plexus corresponded to the lateromedial order of their distribution. However, the dorsoventral boundary was displaced at the inferior margin of the gluteus maximus between the thigh and gluteal branches. The perineal branch originated from the ventral branch of the nerve roots. In addition, the pudendal nerve branches, which ran medially to the ischial tuberosity, were distributed in the medial part of the inferior gluteal region. These branches should be distinguished from the gluteal branches; the former should be classified as the medial inferior cluneal nerves and the latter as the lateral ones. Finally, the medial part of the inferior gluteal region was distributed by branches of the dorsal sacral rami, which may correspond to the medial cluneal nerves. Thus, the composition of the posterior femoral cutaneous nerve is considered necessary when considering the dorsoventral relationships of the sacral plexus and boundaries of the dorsal and ventral rami.

Anatomical basis for contribution of hip joint motion by the obturator internus to defaecation/urinary functions by the levator ani via the obturator fascia

The functional association between hip joint motion and defaecation/urinary function has attracted considerable research and clinical attention owing to the potential novel approaches for pelvic floor rehabilitation; however, the anatomical basis remains unclear. This study, therefore, aimed to analyse the anatomical basis of force transmission between the obturator internus, a muscle of the hip joint, and the levator ani, a muscle of the pelvic floor. Twenty-three cadavers were used for macroscopic and histological analyses. The three-dimensional structures of the muscles and fascia were recorded using a high-definition camera and a 3D scanner. The arrangement and attachment of the muscle fibres, tendons and fascia were visualised using histological sections stained with Masson's trichrome. The obturator internus and levator ani were in broad contact through the obturator fascia. The height of their contact area was 24.6 ± 9.1 mm. Histologically, the obturator internus and levator ani shared a large area of the obturator fascia, and the obturator fascia provided the attachment of several muscle layers of the levator ani. The contribution of hip joint motion to defaecation/urinary function can be explained by the broad 'planar' contact between the obturator internus and levator ani. This anatomical feature suggests that movement of the obturator internus creates the foundation for the function of the levator ani and contributes to pelvic floor support through the obturator fascia. This study provides an anatomical basis for the effectiveness of the hip muscles in improving defaecation/urinary function by enabling balanced and proper movements.

Pelvic floor and perineal muscles: a dynamic coordination between skeletal and smooth muscles on pelvic floor stabilization

The purpose of this review is to present our researches on the pelvic outlet muscles, including the pelvic floor and perineal muscles, which are responsible for urinary function, defecation, sexual function, and core stability, and to discuss the insights into the mechanism of pelvic floor stabilization based on the findings. Our studies are conducted using a combination of macroscopic examination, immunohistological analysis, 3D reconstruction, and imaging. Unlike most previous reports, this article describes not only on skeletal muscle but also on smooth muscle structures in the pelvic floor and perineum to encourage new understanding. The skeletal muscles of the pelvic outlet are continuous, which means that they share muscle bundles. They form three muscle slings that pass anterior and posterior to the anal canal, thus serving as the foundation of pelvic floor support. The smooth muscle of the pelvic outlet, in addition to forming the walls of the viscera, also extends in three dimensions. This continuous smooth muscle occupies the central region of the pelvic floor and perineum, thus revising the conventional understanding of the perineal body. At the interface between the levator ani and pelvic viscera, smooth muscle forms characteristic structures that transfer the lifting power of the levator ani to the pelvic viscera. The findings suggest new concepts of pelvic floor stabilization mechanisms, such as dynamic coordination between skeletal and smooth muscles. These two types of muscles possibly coordinate the direction and force of muscle contraction with each other.

Novel combination method of wide-range serial sectioning and 3D reconstruction visualizing both macro-level dynamics and micro-level interactions in an attempt to analyze the female pelvic floor

The present report presents details of the method for combining wide-range serial sectioning and 3D reconstruction using an adult cadaver. For several decades, anatomists have utilized a variety of non-destructive three-dimensional (3D) visualization methods to complement gross anatomical analysis methods. These include vascular casting for the visualization of vascular morphology and micro-CT for the visualization of bone morphology. However, these conventional methods are restricted by the properties and sizes of the target structures. Here, we introduce a method to conduct 3D reconstruction based on wide-range serial histological sections from adult cadavers, which overcomes previous restrictions. An attempt at 3D visualization of the female pelvic floor muscles provides a detailed description of the procedure. Supplemental video and 3D PDF files allow multifaceted observation of 3D images. Wide-range serial sectioning visualizes morphology beyond the scope of conventional methods, while 3D reconstruction enables non-destructive 3D visualization of any structure that can be observed on a histological section, including skeletal muscle, smooth muscle, ligaments, cartilage, connective tissue, blood vessels, nerves, lymph nodes, and glands. The novel combination of both methods is instrumental in meso-anatomy, a discipline intermediate between macro-anatomy and micro-anatomy.

Histological study of the thin membranous dense connective tissues around the curving portion of the bilateral recurrent laryngeal nerves

OBJECTIVE/AIM

We aimed to demonstrate the anatomical relationship between the recurrent laryngeal nerves (RLNs), thin membranous dense connective tissue (TMDCT [e.g., the visceral or vascular sheaths around the esophagus]), and the lymph nodes around the esophagus at the curving portion of the RLNs for rational and efficient lymph node dissection.

METHODS

Transverse sections of the mediastinum at 5 mm or 1 mm intervals were obtained from four cadavers. Hematoxylin and eosin staining and Elastica van Gieson staining were performed.

RESULTS

The visceral sheaths could not be clearly observed the curving portions of the bilateral RLNs, which were observed on the cranial and medial side of the great vessels (aortic arch and right subclavian artery [SCA]). The vascular sheaths could be clearly observed. The bilateral RLNs diverged from the bilateral vagus nerves, which ran along with the vascular sheaths, went up around the caudal side of the great vessels and the vascular sheath, and ran cranially on the medial side of the visceral sheath. Visceral sheaths were not observed around the region containing the left tracheobronchial lymph nodes (No. 106tbL) or the right recurrent nerve lymph nodes (No. 106recR). The regions containing the left recurrent nerve lymph nodes (No. 106recL) and the right cervical paraesophageal lymph nodes (No. 101R) were observed on the medial side of the visceral sheath, with the RLN.

CONCLUSION

The recurrent nerve, which branched off from the vagus nerve descending along the vascular sheath, ascended the medial side of the visceral sheath after inversion. However, no clear visceral sheath could be identified in the inverted area. Therefore, during radical esophagectomy, the visceral sheath along No. 101R or 106recL may be recognized and available.

Significance of the broad non-bony attachments of the anterior cruciate ligament on the tibial side

Knowledge of the anatomy of the anterior cruciate ligament (ACL) is important to understand the function and pathology of the knee joint. However, on the tibial side of ACL, its structural relationships with the articular cartilage and lateral meniscus remain unclear. Furthermore, conventional research methods are limited to analyzing the bone attachments. We provide a comprehensive, three-dimensional anatomical description of the tibial side of the ACL that questions the principle that “a ligament is necessarily a structure connecting a bone to another bone.” In our study, 11 knees from 6 cadavers were used for macroscopic anatomical examinations, serial-section histological analyses, and three-dimensional reconstructions. The attachments of the tibial side of ACL consisted of attachments to the bone (102.6 ± 27.5 mm²), articular cartilage (40.9 ± 13.6 mm²), and lateral meniscus (6.5 ± 4.6 mm²), suggesting that the ACL has close structural relationships with the articular cartilage and lateral meniscus. Our study demonstrates that the tibial side of the ACL is not attached to the bone surface only and provides new perspectives on ligamentous attachments. Considering its attachment to the articular cartilage would enable more accurate functional evaluations of the mechanical tensioning of the ACL.

An Anatomical Study of Posterior Trunk Recipient Vessels, and Comparisons of Outcome following Pedicled- and Free-Flap Transfers for Treatment of Sarcoma in the Posterior Trunk

BACKGROUND

 Reconstruction after wide resection of a large sarcoma arising in the posterior trunk may require free-flap transfer to reduce the postoperative complications. Here, we describe the recipient vessels on the whole posterior trunk. Moreover, to show the reliability of these vessels, we describe an institutional series of free-flap reconstruction.

METHODS

 In the cadaveric study, 20 posterior trunk regions from 10 fixed cadavers were dissected. The location and the diameter of the perforating artery and vein on the posterior were documented. In the clinical study, 54 patients undergoing immediate reconstruction surgery with only a pedicled flap (n = 45) and with a free flap (n = 9) after sarcoma resection on the posterior trunk between July 2005 and September 2021 were identified. One-to-one propensity score matching was performed to compare the postoperative complications.

RESULTS

 In the cadaveric study, a total of 178 perforators were identified. The average diameter of the superficial cervical artery (SCA) and vein, dorsal scapular artery (DSA) and vein, medial branch of dorsal intercostal artery perforator (m-DICAP) and vein, lateral branch of dorsal intercostal artery perforator (l-DICAP) and vein, and dorsolateral intercostal artery perforator (DLICAP) and vein were 1.03, 1.67, 1.38, 1.84, 1.28, 1.84, 1.01, 1.60, 1.11, and 1.70 mm. In the clinical study, the propensity score-matched analysis involving eight pairs showed a significantly higher occurrence of total complications in the pedicled-flap group than the free-flap group (62.5 vs. 0%, p = 0.03).

CONCLUSION

 The cadaveric study showed that the perforators from the SCA, DSA, and posterior intercostal artery are constantly present. The clinical study demonstrated the feasibility and reliability of a free-flap transfer.

Anatomy of Cowper's gland in humans suggesting a secretion and emission mechanism facilitated by cooperation of striated and smooth muscles

This study presents the detailed anatomy of the Cowper’s gland in humans. Elucidating the mechanism of secretion and emission of the Cowper’s gland requires analysis of the muscles around the Cowper’s gland. We hypothesized that the Cowper’s gland involves not only smooth muscle but also the striated muscles of the pelvic floor. Here, we provide comprehensive and three-dimensional anatomy of the Cowper’s gland and its surrounding structures, which overcomes the current local and planar understanding. In this study, seven male corpses of body donors were used to conduct macroscopic anatomy, histology, and three-dimensional reconstruction. The Cowper’s gland was surrounded laterally and posterosuperiorly by striated and smooth muscles, respectively. The striated muscle bundle was connected from the superficial transverse perineal muscle, levator ani, and external anal sphincter to the external urethral sphincter (rhabdosphincter). The smooth muscle was part of the deep transverse perineal muscle and entered between the bilateral Cowper’s glands and lobules. Our findings indicate that the secretion and emission of the Cowper’s gland in humans are carried out through the cooperation of striated and smooth muscles.

Extraordinary first jejunal arterial variation associated with annular pancreas undergoing pancreaticoduodenectomy for pancreatic cancer: a case report

Purpose

Annular pancreas encountered in adults and jejunal arterial variations are rare. Anatomical variations can cause conflicts between oncology and surgical safety.

Methods

Case report of a 68-year-old man suffering from vomiting because of an annular pancreas and a ductal adenocarcinoma of the pancreas head invading the second portion of the duodenum.

Results

Contrast-enhanced computed tomography showed multiple arterial variations describing the absence of the coeliac trunk such that the left gastric artery (LGA), splenic artery and superior mesenteric artery (SMA) were arising separately from the aorta. The accessory left hepatic artery arose from the LGA; and both the common hepatic artery and combined trunk of the replaced right hepatic artery with the higher replaced first jejunal artery separately arose close to the root of the SMA. The patient underwent curative pancreaticoduodenectomy which achieved 3 years of recurrence-free survival.

Conclusion

This was an extraordinary case of annular pancreas with first jejunal arterial variation detailing an embryological interpretation as well as considerations for balancing short- and long-term outcomes.

What comprises the plate-like structure between the pancreatic head and the celiac trunk and superior mesenteric artery? A proposal for the term "P-A ligament" based on anatomical findings

A plate-like structure is located posterior to the portal vein system, between the pancreatic head and roots and/or branches of two major arteries of the aorta: the celiac trunk and superior mesenteric artery. We aimed to clarify the distribution and components of this plate-like structure. Macroscopic examination of the upper abdomen and histological examination of the plate-like structure were performed on 26 cadavers. The plate-like structure is connected to major arteries (aorta, celiac trunk, superior mesenteric artery) and the pancreatic head; it contains abundant fibrous bundles comprising nerves, vessels, collagen fibers, and adipose tissue. Furthermore, it consists of three partly overlapping fibrous components: rich fibrous bundles (superior mesenteric artery plexus) fused to the uncinate process of the pancreas; fibrous bundles arising from the right celiac ganglion and celiac trunk that spread radially to the dorsal side of the pancreatic head and superior mesenteric artery plexus; and fibrous bundles, accompanied by the inferior pancreaticoduodenal artery, entering the pancreatic head. The plate-like structure is the pancreas–major arteries (aorta, celiac trunk, superior mesenteric artery) ligament (P–A ligament). The term “P–A ligament” may be clinically useful and can facilitate comprehensive understanding of the anatomy surrounding the pancreatic head and provide an anatomical basis for further pancreatic surgery studies.

The series of smooth muscle structures in the pelvic floors of men: Dynamic coordination of smooth and skeletal muscles

Introduction

Recent studies have revealed the extended nature of smooth muscle structures in the pelvic floor, revising the conventional understanding of the “perineal body.” Our aim was to clarify the three‐dimensional configuration and detailed histological properties of the smooth muscle structures in the region anterior to the rectum and anal canal in men.

Materials and methods

Four male cadavers were subjected to macroscopic and immunohistological examinations. The pelvis was dissected from the perineal side, as in the viewing angle during transperineal surgeries. Serial transverse sections of the region anterior to the rectum and anal canal were stained with Masson's trichrome and immunohistological stains to identify connective tissue, smooth muscle, and skeletal muscle.

Results

There was a series of smooth muscle structures continuous with the longitudinal muscle of the rectum in the central region of the pelvic floor, and three representative elements were identified: the anterior bundle of the longitudinal muscle located between the external anal sphincter and bulbospongiosus; bilateral plate‐like structures with transversely‐oriented and dense smooth muscle fibers; and the rectourethral muscle located between the rectum and urethra. In addition, hypertrophic tissue with smooth muscle fibers extended from the longitudinal muscle in the anterolateral portion of the rectum and contacted the levator ani.

Conclusions

The series of smooth muscle structures had fiber orientations and densities that differed among locations. The widespread arrangement of the smooth muscle in the pelvic floor suggests a mechanism of dynamic coordination between the smooth and skeletal muscles.

Reduced induction of human β-defensins is involved in the pathological mechanism of cutaneous adverse effects caused by epidermal growth factor receptor monoclonal antibodies

Epidermal growth factor receptor inhibitors (EGFRIs) frequently cause cutaneous adverse effects such as papulopustular eruptions. However, the mechanism of the reactions remains unclear. To assess the pathological mechanism of cutaneous adverse reactions caused by EGFRIs, we investigated whether EGFRIs have an influence on the innate immune response of the skin. Levels of human β-defensins (hBDs), which serve as the first line of defence against infection by pathogenic microorganisms, in the stratum corneum samples of patients treated with EGFR. monoclonal antibodies were measured before and after starting therapy. There were no obvious trends in hBD production in patients without eruptions, whereas a significant decrease in hBD1 and hBD3 production and a nonsignficant decrease in hBD2 production were observed in patients who developed papulopustular eruptions. Our results suggest that a reduction in hBD contributes to the increased incidence of papulopustular eruptions.

Spatial distribution of smooth muscle tissue in the female pelvic floor and surrounding the urethra and vagina

Data regarding urethral supporting structures are insufficient for understanding the mechanism of stress urinary incontinence. Whether smooth muscle fibers contribute to urethral support and pelvic floor support structures is unclear. This study aimed to clarify the histological structures and spatial distributions of smooth muscle tissues surrounding the urethra and vagina. Using cadaveric specimens, macroscopic anatomical and histological evaluations were conducted. Six female cadavers were used for macroscopic observations. Ten female cadavers were used for histological observations. Three pelvises were cut in a plane vertical to the urethra, and the other pelvises were cut in a plane parallel to the urethra and vagina to observe tissues surrounding the urethra and vagina. The major tissue component around the proper muscle layer of the urethra was smooth muscle tissue, which mediated among the urethra, pubis, and levator ani. Smooth muscle tissues laterally extended the smooth muscle fibers, both superiorly and inferiorly toward the levator ani, with a few fibers inserted in the levator ani. Smooth muscle was found between the urethral walls and pubic bones. Smooth muscle may contribute to the mechanism of pelvic floor support.

Zoning inside the renal fascia: The anatomical relationship between the urinary system and perirenal fat

Objectives

To examine the anatomical relationship between the urinary system and perirenal fat, and to clarify the zoning inside the renal fascia.

Methods

Using computed tomography images from 50 men, we examined perinephric veins to reveal vessel communication in perirenal fat. Nine cadavers were dissected to investigate connective tissue continuity and vessel communication inside the renal fascia. Eight retroperitoneal specimens were macroscopically observed: four from the anterior and four from the posterior aspects. One specimen was used to obtain retroperitoneal transverse sections to study macroscopic anatomy and histology.

Results

Perinephric veins were classified into four types (superior, middle, inferior and lateral) using computed tomography. Most of the inferior perinephric veins were connected to the ipsilateral gonadal vein. In the cadaveric study, the superior and middle perinephric veins communicated with veins deriving from the ipsilateral adrenal gland. A fibrous connective tissue gap between perirenal fat and renal hilar fat was observed in posterior aspect dissection. From the gap, we could dissect the urinary system from perirenal fat en bloc along with a thin fibrous connective tissue layer. Communicating vessels between perirenal fat and the urinary system were rare.

Conclusions

Our results suggest that perirenal fat belongs to the connective tissue of the gonad and the adrenal gland. The urinary system is separate from perirenal fat, and is located on the dorsal side inside the renal fascia. This concept of zoning inside the renal fascia is valuable particularly in retroperitoneoscopic donor nephrectomy.

Three muscle slings of the pelvic floor in women: an anatomic study

The region anterior to the anal canal in women is composed of intertwined smooth and skeletal muscles. The present study aimed to clarify skeletal muscle morphology in the anterior region of the anal canal. The pelvic floor muscles of 28 pelvic halves from 16 female cadavers (mean age 79.75 years) were dissected from the inferior aspect to examine the perineal muscles, followed by midline transection and dissection from the inner surface to examine the pelvic outlet muscles. The bulbospongiosus muscle was found to be attached to the lateral surface of the external anal sphincter. The superficial transverse perineal muscle crossed superiorly to the bulbospongiosus and coursed medially toward its contralateral muscle bundle deep to the anterior portion of the external anal sphincter. The superficial transverse perineal muscle formed the middle sling. From the medial aspect, the anterior part of the levator ani was divided into anterior and posterior bundles to form the anterior and posterior slings, respectively. This study proposes that three muscular slings could be important in supporting the pelvic floor in women. In addition, this study shows that the anterior skeletal muscular wall of the anal canal is composed of the anterior muscle bundle of the levator ani, superficial transverse perineal, and proper external anal sphincter muscles.

Deep cervical fascia as an anatomical landmark of lingual lymph nodes: An anatomic and histologic study

OBJECTIVES

We aimed to discuss the definition of lingual lymph nodes based on the deep cervical fascia anatomy.

METHODS

A total of 11 cadavers were histopathologically evaluated. Specimens were dissected into serial stepwise cross-sections. The deep cervical fascia and lymph nodes were evaluated by staining the cross-sections with Elastica van Gieson and hematoxylin and eosin stains, respectively. The gross anatomy of the deep cervical fascia was evaluated in 1 cadaver after bilateral dissection.

RESULTS

A single severely degenerated medial lingual lymph node (MLLN) was identified in the lingual septum of 1 cadaver. A single lateral lingual lymph node (LLLN) was identified in 1 cadaver, between the genioglossus and the hyoglossus. The superficial layer of deep cervical fascia (SLDF) was found to split into two layers encapsulating the submandibular gland. The deeper portion of this fascia was in close contiguity with the hyoglossus and formed the boundary between the mouth and the neck. The SLDF was found to be discontinuous with the area between the sublingual space and the submandibular gland.

CONCLUSIONS

The SLDF could serve as an anatomical landmark for lingual lymph nodes, since it is considered to be the demarcating boundary during neck dissection. When lymph nodes that are located deeper than the SLDF were defined as lingual lymph nodes, 1 MLLN and 1 LLLN were identified.

Coexistence of Dense and Sparse Areas in the Longitudinal Smooth Muscle of the Anal Canal: Anatomical and Histological Analyses Inspired by Magnetic Resonance Images

Magnetic resonance images of the anal canal show small, circular, low‐intensity areas arranged in a row and a high‐intensity area surrounding them internally and externally in the longitudinal muscle layer that cannot be explained by current anatomical findings. The purpose of this study was to elucidate the detailed structure of the longitudinal smooth muscle of the anal canal and to interpret the magnetic resonance image of the longitudinal muscle. Specimens for macroscopic anatomy and histology were obtained from six and seven cadavers, respectively. The histological nature of the longitudinal muscle was examined by staining serial transverse and coronal sections of the lateral wall of the anal canal with Masson's trichrome stain and using immunohistochemistry for smooth and skeletal muscle fibers. Dense and sparse areas of smooth muscle fibers coexisted in the longitudinal muscle layer. The dense areas formed columnar muscle bundles approximately 1.0–1.5 mm in diameter, and they continued from the longitudinal muscle bundles of the rectum. The columnar muscle bundles of the longitudinal anal muscle were internally and externally surrounded by sparsely arranged smooth muscle fibers that ran longitudinally. The coexistence of dense and sparse areas of smooth muscle fibers suggests that the structure of the smooth muscle is optimized for its function. This histological nature is probably reflected in the magnetic resonance image of the longitudinal muscle as the coexistence of low‐ and high‐intensity areas. Clin. Anat. 33:619–626, 2020. © 2019 Wiley Periodicals, Inc.

Anatomy of the smooth muscle structure in the female anorectal anterior wall: convergence and anterior extension of the internal anal sphincter and longitudinal muscle

AIM

The anatomy of the region between the vagina and anal canal plays an essential role when performing a proctectomy for low-lying tumours. However, the anatomical characteristics of this area remain unclear. The purpose of the present study was to clarify the configuration, and both lateral and inferior extensions, of the muscle bundles in the anorectal anterior wall in females.

METHODS

Using cadaveric specimens, macroscopic anatomical and histological evaluations were conducted at the anatomy department of our institute. Macroscopic anatomical specimens were obtained from six female cadavers. Histological specimens were obtained from eight female cadavers.

RESULTS

The smooth muscle fibres of the internal anal sphincter and longitudinal muscle extended anteriorly in the anorectal anterior wall of females and the muscle bundles showed a convergent structure. The anterior extending smooth muscle fibres merged into the vaginal smooth muscle layer, distributed subcutaneously in the vaginal vestibule and perineum and spread to cover the anterior surface of the external anal sphincter and the levator ani muscle. Relatively sparse space was observed in the region anterolateral to the rectum on histological analysis.

CONCLUSION

Smooth muscle fibres of the rectum and vagina are intermingled in the median plane, and there is relatively sparse space in the region anterolateral to the rectum. Therefore, when detaching the anorectal canal from the vagina during proctectomy, an approach from both the lateral sides should be used.

Anatomic analysis of the whole articular capsule of the shoulder joint, with reference to the capsular attachment and thickness

Background

Although conventional Bankart repair has been the accepted procedure for traumatic anterior glenohumeral instability, the humeral avulsion of the glenohumeral ligament or an elongation of the capsule remains challenging to decide the appropriate treatment. The anatomical knowledge regarding the whole capsule of glenohumeral joint is necessary to accurately treat for the capsular disorders. The aims of the current study were to investigate the anatomical features of capsular attachment and thickness in a whole capsule of glenohumeral joint.

Methods

We used 13 shoulders in the current study. In 9 shoulders, we macroscopically measured the attachment widths of the capsulolabrum complex on the scapular glenoid, and the attachment widths of the capsule on the humerus in reference to the scapular origin of the long head of triceps brachii, and the humeral insertion of the rotator cuff tendons. We additionally used 4 cadaveric shoulders, which were embalmed using Thiel’s method, for the analysis of the thickness in a whole capsule by using micro-CT.

Results

The glenoidal attachment of the articular capsule appeared to have a consistent width except for the superior part of the origin of the long head of triceps brachii. On the humerus, the articular capsule was widely attached to areas without overlying rotator cuffs, with the widest width (17.3 ± 0.9 mm) attached to the axillary pouch. The inferior part of the capsule, which was consistently thicker than the superior part, continued to the superior part along the glenoid and humeral side edge.

Conclusions

The current study showed that the inferior part of the glenohumeral capsule had a wide humeral attachment from the inferior edge of the subscapularis insertion to the inferior edge of the teres minor insertion via the anatomical neck of the humerus, and the thickness of it was thicker than the superior part of the capsule.

The extended bundle of the tensor veli palatini: Anatomic consideration of the dilating mechanism of the Eustachian tube

OBJECTIVE

The aim of this study was to analyze the topographical structures of the muscles surrounding the Eustachian tube.

MATERIALS AND METHODS

We conducted macroscopic and histological studies of 24 halves of 12 heads from Japanese cadavers.

RESULTS

The main findings were as follows: 1) the infero-lateral muscle bundles of the tensor veli palatini didn't turn medially at the pterygoid hamulus but were distributed laterally and continuous with the buccinator; 2) the tensor veli palatini attached laterally to the membranous part of the Eustachian tube; 3) the superior pharyngeal constrictor was not only adjacent to the buccinator at the pterygomandibular raphe but also had muscular continuation with it laterally and 4) some bundles of the superior pharyngeal constrictor adhered with the palatine aponeurosis.

CONCLUSION

We believe that the cooperation of the muscles contributes to the dilating mechanism of the Eustachian tube, due to the complex topographical structures of the surrounding muscles: the tensor veli palatini, the levator veli palatini, the superior pharyngeal constrictor and the buccinator.

Mouth breathing, another risk factor for asthma: the Nagahama Study

BACKGROUND

Allergic rhinitis, a known risk factor for asthma onset, often accompanies mouth breathing. Mouth breathing may bypass the protective function of the nose and is anecdotally considered to increase asthma morbidity. However, there is no epidemiological evidence that mouth breathing is independently associated with asthma morbidity and sensitization to allergens. In this study, we aimed to clarify the association between mouth breathing and asthma morbidity and allergic/eosinophilic inflammation, while considering the effect of allergic rhinitis.

METHODS

This community-based cohort study, the Nagahama Study, contained a self-reporting questionnaire on mouth breathing and medical history, blood tests, and pulmonary function testing. We enrolled 9804 general citizens of Nagahama City in the Shiga Prefecture, Japan.

RESULTS

Mouth breathing was reported by 17% of the population and was independently associated with asthma morbidity. The odds ratio for asthma morbidity was 1.85 (95% CI, 1.27-2.62) and 2.20 (95% CI, 1.72-2.80) in subjects with mouth breathing alone and allergic rhinitis alone, which additively increased to 4.09 (95% CI, 3.01-5.52) when mouth breathing and allergic rhinitis coexisted. Mouth breathing in nonasthmatics was a risk for house dust mite sensitization, higher blood eosinophil counts, and lower pulmonary function after adjusting for allergic rhinitis.

CONCLUSION

Mouth breathing may increase asthma morbidity, potentially through increased sensitization to inhaled allergens, which highlights the risk of mouth-bypass breathing in the 'one airway, one disease' concept. The risk of mouth breathing should be well recognized in subjects with allergic rhinitis and in the general population.

Smoking attenuates the age-related decrease in IgE levels and maintains eosinophilic inflammation

BACKGROUND

Epidemiological studies have shown that smoking increases the propensity for atopy and asthma. However, the effects of smoking on atopy and eosinophilic inflammation in asthmatics, including the elderly, remain unknown.

OBJECTIVE

To determine the effects of smoking on serum immunoglobulin E (IgE) levels and eosinophilic inflammation in asthmatics of all ages.

METHODS

The associations of serum IgE levels, blood eosinophil counts and fractional exhaled nitric oxide (FeNO) levels with smoking and age in steroid-naive asthmatics were cross-sectionally assessed (n = 307). Levels of sputum eosinophil and thymic stromal lymphopoietin (TSLP) that promotes Th2 inflammation were also analysed. Current smokers were excluded when analysing contributing factors of FeNO.

RESULTS

Levels of serum IgE, blood eosinophil and FeNO decreased with increasing age in never-smokers, whereas decrease in serum IgE levels with increasing age was not observed in current smokers. In addition, current smoking was associated with higher blood eosinophil counts. In atopic asthmatics, age-related declines in serum IgE levels were less steep in ex-smokers than in never-smokers, and atopic ex-smokers with asthma showed higher blood eosinophil counts and higher FeNO irrespective of age. Lastly, sputum TSLP levels were associated with sputum eosinophil proportions and pack-years. Current and ex-smokers had higher TSLP levels than never-smokers.

CONCLUSIONS AND CLINICAL RELEVANCE

In steroid-naive asthmatics, smoking may attenuate the age-related decrease in IgE levels and maintain eosinophilic inflammation, in which TSLP may be involved.

Dynamic intersection of the longitudinal muscle and external anal sphincter in the layered structure of the anal canal posterior wall

PURPOSE

The minute details of the structure of the anal canal are still not well understood. The complex structural configuration of the muscles, ligaments and raphes remains unclarified. This study was undertaken to determine the precise structure of the posterior part of the anal canal and to facilitate an understanding of previous studies.

METHODS

For macroscopic examination, 14 right pelvic halves from 14 Japanese cadavers were used. Observation and dissection were performed from the median plane. In the histological examination, six left pelvic halves were used. The sections of the posterior parts of the anal canal were stained with hematoxylin and eosin, Elastic van Gieson, anti-smooth actin antibody and anti-skeletal myosin antibody.

RESULTS

We identified the following muscles arranged from the internal side to the external side: internal anal sphincter, longitudinal muscle (LM), external anal sphincter (EAS) and levator ani muscle (LAM). Two different types of conformation of the posterior part of the anal canal were found, each bearing a different shape of EAS. In both types, LM penetrated the inferior part of EAS. After penetrating EAS, some fibers of LM ran posterosuperiorly and attached to the "the posterior fibers" which reach the dorsal side of the coccyx.

CONCLUSIONS

We defined and labeled the connective tissues between the anal canal and coccyx on the basis of their relative position to LAM. Based on a comparison of the two types of the posterior part of the anal canal, we propose that there are two phases due to constriction and relaxation of LM.

Predictors of 5-year mortality in pulmonary Mycobacterium avium-intracellulare complex disease

SETTING

Kyoto, Japan.

OBJECTIVE

To determine predictors of 5-year mortality in pulmonary Mycobacterium avium-intracellulare complex (MAC) disease.

DESIGN

Retrospective study of 164 patients diagnosed with pulmonary MAC disease between 1999 and 2005 and followed for 5 years.

RESULTS

Overall 5-year mortality was 28.0%. Among 117 patients with microbiological outcomes, 54 were treated (treated MAC patients) and 24 were not treated and did not experience sputum culture conversion during follow-up (untreated chronic MAC patients); 39 patients were not treated and experienced sputum culture conversion. Five-year all-cause overall mortality among the 78 patients with definite MAC disease (including treated and untreated chronic MAC patients) was 25.6%. The mortality rate was 33.3% for untreated chronic MAC patients only vs. 22.2% for treated MAC patients (P = 0.30). After adjustment for clinical, microbiological and radiological confounders, independent factors for 5-year mortality were a high Charlson comorbidity index in cases with definite MAC disease (hazard ratio [HR] 1.76) and untreated chronic MAC (HR 3.08), and presence of cavitary lesions in cases with definite MAC disease (HR 1.82) and treated MAC patients (HR 3.91).

CONCLUSION

Patients with cavitary lesions require immediate treatment for sputum culture conversion and to improve their chances of survival.

Body mass index in male patients with COPD: correlation with low attenuation areas on CT

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterised by the presence of airflow limitation caused by loss of lung elasticity and/or airway narrowing. The pathological hallmark of loss of lung elasticity is emphysema, and airway wall remodelling contributes to the airway narrowing. Using CT, these lesions can be assessed by measuring low attenuation areas (LAA) and airway wall thickness/luminal area, respectively. As previously reported, COPD can be divided into airway dominant, emphysema dominant and mixed phenotypes using CT. In this study, it is postulated that a patient's physique may be associated with the relative contribution of these lesions to airflow obstruction.

METHODS

CT was used to evaluate emphysema and airway dimensions in 201 patients with COPD. Emphysema was evaluated using percentage of LAA voxels (LAA%) and airway lesion was estimated by percentage wall area (WA%). Patients were divided into four phenotypes using LAA% and WA%.

RESULTS

Body mass index (BMI) was significantly lower in the higher LAA% phenotype (ie, emphysema dominant and mixed phenotypes). BMI correlated with LAA% (rho = -0.557, p<0.0001) but not with WA%. BMI was significantly lower in the emphysema dominant phenotype than in the airway dominant phenotype, while there was no difference in forced expiratory volume in 1 s %predicted between the two.

CONCLUSION

A low BMI is associated with the presence of emphysema, but not with airway wall thickening, in male smokers who have COPD. These results support the concept of different COPD phenotypes and suggest that there may be different systemic manifestations of these phenotypes.

High sensitivity C-reactive protein in asthma

Asthma is characterised by chronic inflammation of the airways, but the relevance of high-sensitivity assays for C-reactive protein (hs-CRP), which are known to be a sensitive marker of low-grade systemic inflammation, has not been fully studied in asthma. The objective was to examine serum hs-CRP levels in patients with asthma and their relationship to clinical characteristics and degree of airway inflammation. Serum hs-CRP levels were cross-sectionally examined in steroid-naive (n = 22) and steroid-inhaling (n = 23) adult patients with asthma and healthy controls (n = 14). All were nonsmokers. Serum hs-CRP levels were significantly increased in steroid-naive patients (mean+/-sd 1.33+/-1.48 mg.L(-1)) compared with controls (0.21+/-0.30 mg.L(-1)), but not in patients on inhaled corticosteroid. Among steroid-naive patients, serum hs-CRP levels significantly negatively correlated with indices of pulmonary function (forced expiratory volume in one second/forced vital capacity and forced mid-expiratory flow) and positively with sputum eosinophil count. Among patients on inhaled corticosteroid, hs-CRP levels did not correlate with any indices. In conclusion, an increase in serum C-reactive protein levels measured by high-sensitivity assays may be associated with airflow obstruction and airway inflammation, and may serve as a surrogate marker of airway inflammation in asthma.

Targeting of antioxidant and anti-thrombotic drugs to endothelial cell adhesion molecules

The endothelium represents an important therapeutic target for containment of oxidative stress, thrombosis and inflammation involved in a plethora of acute and chronic conditions including cardiovascular and pulmonary diseases and diabetes. However, rapid blood clearance and lack of affinity to the endothelium compromise delivery to target and restrict medical utility of antioxidant enzymes (e.g., catalase) and fibrinolytics. The use of "stealth" PEG-liposomes prolongs circulation, whereas conjugation with antibodies to endothelial determinants permits targeting. Constitutive endothelial cell adhesion molecules (CAM, such as ICAM-1 and PECAM-1, which are stably expressed and functionally involved in oxidative stress and thrombosis) are candidate determinants for targeting of antioxidants and fibrinolytics. CAM antibodies and compounds conjugated with anti-CAM bind to endothelial cells and accumulate in vascularized organs (preferentially, lungs). Pathological stimuli enhance ICAM-1 expression in endothelial cells and facilitate targeting, whereas PECAM-1 expression and targeting are stable. Endothelial cells internalize 100-300 nm diameter conjugates possessing multiple copies of anti-CAM, but not monomolecular antibodies or micron conjugates. This permits size-controlled sub-cellular targeting of antioxidants into the endothelial interior and fibrinolytics to the endothelial surface. Targeting catalase to PECAM-1 or ICAM-1 protects endothelial cells against injury by oxidants in culture and alleviates vascular oxidative stress in lungs in animals. Anti-CAM/catalase conjugates are active for a few hours prior to lysosomal degradation, which can be delayed by auxiliary drugs. Conjugation of fibrinolytics to monovalent anti-ICAM permits targeting and prolonged retention on the endothelial surface. Therefore, CAM targeting of antioxidants and fibrinolytics might help to contain oxidative and thrombotic stresses, with benefits of blocking CAM. Avenues for improvement and translation of this concept into the clinical domain are discussed.

Relationship of airway wall thickening to an imbalance between matrix metalloproteinase-9 and its inhibitor in asthma

BACKGROUND

The balance between matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) may be critical in extracellular matrix remodelling, a characteristic of asthmatic airways. An excess of TIMP-1 over MMP-9 has been associated with chronic airflow obstruction but the mechanisms underlying this association remain unknown. Recent computed tomographic (CT) studies indicate that airway wall thickening is associated with chronic airflow obstruction.

METHODS

Sputum levels of MMP-9, TIMP-1, and their molar ratio were examined in 26 patients with stable asthma and their relationship with pulmonary function and airway wall thickness, assessed by a validated CT technique which measured wall area corrected by body surface area (WA/BSA), the ratio of WA to outer wall area (WA%), and the absolute wall thickness corrected by radicalBSA of a segmental bronchus (T/ radicalBSA), was examined.

RESULTS

Sputum MMP-9 levels were inversely correlated with WA% and TIMP-1 levels were positively correlated with WA/BSA and T/ radicalBSA. The MMP-9/TIMP-1 molar ratio was inversely correlated with WA% and T/ radicalBSA and positively correlated with post-bronchodilator values of mid-forced expiratory flow and maximum expiratory flow at the quartile of lung volume.

CONCLUSION

Excess TIMP-1 may have a pathogenetic role in airway wall thickening in asthmatic patients which may result in chronic airflow obstruction.

Effect of PCCB gene mutations on the heteromeric and homomeric assembly of propionyl-CoA carboxylase

Propionic acidemia is an inherited metabolic disorder caused by deficiency of propionyl-CoA carboxylase, a dodecameric enzyme composed of alpha-PCC and beta-PCC subunits (encoded by genes PCCA and PCCB) that have been associated with a number of mutations responsible for this disease. To clarify the molecular effect associated with gene alterations causing propionic acidemia, 12 different mutations affecting the PCCB gene (R67S, S106R, G131R, R165W, R165Q, E168K, G198D, A497V, R512C, L519P, W531X, and N536D) were analyzed for their involvement in alpha-beta heteromeric and beta-beta homomeric assembly. The experiments were performed using the mammalian two-hybrid system, which was assayed at two different temperatures to distinguish between mutations directly involved in interaction and those probably affecting polypeptide folding, thus indirectly affecting the correct assembly. Mutations R512C, L519P, W531X, and N536D, located at the carboxyl-terminal end of the PCCB gene, were found to inhibit alpha-beta heteromeric and/or the beta-beta homomeric interaction independently of the cultivation temperature, reflecting their primary effect on the assembly. Two mutations A497V and R165Q did not affect either heteromeric or homomeric assembly. The remaining mutations (R67S, S106R, G131D, R165W, E168K, and G198D), located in the amino-terminal region of the beta-polypeptide, resulted in normal interaction levels only when expressed at the lower temperature, suggesting that these changes could be considered as folding defects. From these results and the clinical manifestations associated with patients bearing the mutations described above, several genotype-phenotype correlations may be established. In general, the temperature-sensitive mutations are associated with a less severe, although variable phenotype. This could correlate with the recent hypothesis that the effect of folding mutations can be influenced by the capacity of the cellular protein quality control machinery, which provides clues to our understanding of the variability of the clinical symptoms observed among the patients bearing these mutations.

Expression of IL-15 in inflammatory pulmonary diseases

BACKGROUND

IL-15 is a T(H)1-related cytokine that shares many biologic activities with IL-2. Both cytokines bind a specific alpha subunit, and they share the same beta and gamma common receptor subunits for signal transduction. IL-15 has recently been shown to be upregulated in T cell-mediated inflammatory disorders, such as rheumatoid arthritis and inflammatory bowel diseases. However, the role and expression of IL-15 in inflammatory lung disease has not been investigated.

OBJECTIVE

In the present study we have evaluated the expression of IL-15 mRNA and protein in bronchial biopsy specimens obtained from patients with sarcoidosis (n = 8), tuberculosis (n = 7), chronic bronchitis (n = 10), and bronchial asthma (n = 8) and compared its expression with that seen in normal control subjects (n = 11).

METHODS

In situ hybridization and immunocytochemistry were used to detect the number of cells expressing IL-15 mRNA and protein, respectively, within sections of bronchial tissues from all subject groups. In addition, double immunocytochemistry was used to characterize the cellular source of IL-15.

RESULTS

The number of IL-15(+) cells was significantly higher within tissue from patients with sarcoidosis, tuberculosis, and chronic bronchitis compared with that in asthmatic patients and normal control subjects. Similar results were obtained for IL-15 immunoreactivity by using immunohistochemistry. Furthermore, double immunostaining revealed that neutrophils and macrophages are the major source of IL-15.

CONCLUSION

These results suggest that the expression of IL-15 may be associated with T(H)1-mediated chronic inflammatory diseases of the lung.

GRbeta expression in nasal polyp inflammatory cells and its relationship to the anti-inflammatory effects of intranasal fluticasone

BACKGROUND

Nasal polyposis disease is an inflammatory disorder with intense eosinophilic infiltration of respiratory mucosa that is often difficult to control with topical steroids. Recent evidence suggests that overexpression of the glucocorticoid receptor splice variant GRbeta in inflammatory cells might contribute to steroid insensitivity in diseases such as asthma.

OBJECTIVE

The purposes of this investigation were to determine whether nasal polyp (NP) inflammatory cells overexpress GRbeta and to examine whether GRbeta overexpression is associated with insensitivity to the potent topical steroid fluticasone propionate (FP).

METHODS

Biopsies were obtained from 10 subjects with NPs before and 4 weeks after treatment with intranasal FP. Middle turbinates biopsies from 6 healthy, nonallergic subjects served as normal controls. Biopsies were immunostained for inflammatory cell markers as well as GRbeta and probed for various cytokine mRNA. The anti-inflammatory response to FP was examined in relation to pretreatment levels of GRbeta expression.

RESULTS

The total numbers of inflammatory cells were increased in NPs. The percentage of inflammatory cells expressing GRbeta was also increased (40.5% +/- 19.2% vs 16.1% +/- 4.0%, P =.009). GRbeta expression in NPs was almost exclusive to T lymphocytes, eosinophils, and macrophages. An inverse correlation was observed between the baseline inflammatory cell GRbeta expression and the reduction after FP treatment in EG2-positive eosinophils, CD4-positive T lymphocytes, endothelial VCAM-1 expression, and IL-4 mRNA-positive cells. NPs that were "FP-insensitive" in terms of suppression of eosinophil numbers (major basic protein-positive) had a significantly greater percentage of GRbeta-positive inflammatory cells, a higher ratio of GRbeta-positive/GRalpha-positive cells, and increased numbers of GRbeta-positive eosinophils and macrophages in comparison with those that were "FP-sensitive." "FP-insensitive" NPs also demonstrated a higher percentage of IL-5-positive inflammatory cells expressing GRbeta before and after FP treatment.

CONCLUSION

GRbeta expression appears to be a marker of steroid insensitivity in NPs. Expression of GRbeta by NP inflammatory cells, particularly T cells and eosinophils, might render them resistant to suppression by topical steroids and thereby contribute to persistent NP inflammation.

Altered growth response to prostaglandin E2 and its receptor signaling in mesangial cells from stroke-prone spontaneously hypertensive rats

OBJECTIVE

Prostaglandin (PG) E2, a major arachidonic acid metabolite in the kidney, acts on four receptor subtypes (EP1, EP2, EP3 and EP4). One of major causes of end-stage renal failure is hypertensive renal disease, in which enhanced renal PGE2 production has been shown. In this study, to explore the pathophysiological significance of EP subtypes in the kidney, we examined the role of EP subtypes on proliferation of mesangial cells (MCs) from stroke-prone spontaneously hypertensive rats (SHRSPs), which show faster growth than those from normotensive Wistar-Kyoto rats (WKYs).

DESIGN AND METHODS

Using MCs from SHRSPs and WKYs, we investigated DNA synthesis and its upstream event, the phosphorylation of extracellular signal-regulated kinase (ERK), together with the gene expression of EP subtypes.

RESULTS

Sulprostone, an EP1 agonist, dose-dependently increased DNA synthesis and the phosphorylation of ERK in MCs from both strains. The EP4 agonist, 11-deoxy-PGE1, inhibited sulprostone-induced phosphorylation of ERK in WKY-MCs. In contrast, 11-deoxy-PGE1 failed to inhibit the ERK activity in SHRSP-MCs. Interestingly, cAMP production mediated by EP4 was markedly attenuated in SHRSP-MCs as compared with that in WKY-MCs, despite the overproduction of endogenous PGE2 in SHRSP-MCs. Similar gene expressions of EP1 and EP4 and only faint expression of EP3 were detected in MCs from both strains.

CONCLUSIONS

These results indicate that the PGE2/EP4 system counteracts the PGE2/EP1 system at the level of the intracellular signaling pathway. The altered EP4 signaling may play a critical role in the exaggerated mesangial growth in SHRSPs.

Distorted trachea in patients with chronic obstructive pulmonary disease

BACKGROUND AND OBJECTIVES

We evaluated the size and configuration of the trachea in patients with chronic obstructive pulmonary disease (COPD; n = 35) on high-resolution computed tomography (HRCT) images and compared them with those of healthy volunteers (n = 24).

METHODS

Using a newly developed computed method for analyzing the digital data of HRCT, the size and configuration of the trachea were automatically evaluated.

RESULTS

The size of the trachea of the COPD subjects was the same as that of the control subjects; however, the configuration was more distorted in the COPD patients. There was no difference in the tracheal index (TI), which is the ratio of the coronal to the sagittal length, between these two groups; however, the ratio of the short to the long radius (SR/LR) was significantly smaller in the COPD group than in the control group. There was a significant correlation between SR/LR and airflow limitation as assessed by pulmonary function tests in the COPD group.

CONCLUSIONS

The SR/LR is a better index of tracheal deformity than the classical TI. This deformity is not a consequence secondary to hyperinflation or emphysematous change of the lung, because the low attenuation area of the lung was not correlated with SR/LR.