Biomedical subjects

Gen Murakami

Publications and source records attributed to Gen Murakami.

At least 55 records · Page 3Linked to original sources

PubMed2004

Histologic heterogeneity and intranodal shunt flow in lymph nodes from elderly subjects: a cadaveric study.

Gaps of the superficial cortex of the lymph node provide intranodal shunts that are more often the cause of skip metastasis than are collateral vessels. Examination of lymph nodes from cadavers of elderly subjects often revealed cortical gaps, especially in specific three-dimensional assembled cords; these cortical gaps were readily seen in para-aortic and pelvic nodes. This architecture seemed to be more appropriate for a systemic immune response than a local defense. Evidence of poorly developed cortices, anthracosis, and hyalinization also suggested impaired nodal function. We suspect that this histologic heterogeneity, perhaps a result of aging, affects the nodal trapping of colorimetric/isotopic tracers and metastatic cancer cells. This may have implications for lymphatic mapping of the sentinel lymph node in elderly patients with early-stage cancer.

Aged↗

PubMed2004

Lateral ligament injury of the ankle and associated articular cartilage degeneration in the talocrural joint: anatomic study using elderly cadavers.

We investigated degenerative changes (DCs) of the articular cartilage using 33 cadaveric talocrural joints with anterior talofibular ligament injuries. The control group (93 normal ankles) were age- and sex-matched with the injury group. The injured ligament carried unusual wavy collagen bundles with hyalinization (or elongation) or rupture with scar. In both groups, we found talar-side dominance of DCs, multifocus occurrence, and a high incidence of mirror-image DCs in the medial parts of the joint. However, the mirror-image lesion was multiple or large (or both) in the injury group in contrast to its restricted nature in the control. Thus, the averaged numbers of affected areas or sectors in the injury group were almost twice as large as in the controls. A significantly high incidence of DCs, especially of the mirror-image lesion, was found in the lateral malleolar facet in the injury group. Although initial DC lesions might be at a medial site in the joint, as hypothesized in the control group, the lateral ligament injury seemed to increase the dominance of DCs on the lateral site. Consequently, early evaluation and treatment for lateral ligament insufficiency is more necessary in elderly patients than in younger patients to avoid widespread development of osteoarthritis.

Aged↗

PubMed2004

Does the fabella contribute to the reinforcement of the posterolateral corner of the knee by inducing the development of associated ligaments?

The fabellofibular (FF) and arcuate ligaments are closely colocated at the posterolateral corner of the knee. However, a bony fabella is often absent in Japanese subjects. We investigated these structures morphometrically using 212 knees. A thick FF ligament was found in 38.1% (40/105) of knees with a hard fabella. When identified histologically, a bony fabella accompanied a thick FF in 82.8% (24/29). Conversely, a thin or indefinite FF ligament and an elastic-textured fabella co-existed in 77.9% (60/70) of knees. There were no strong correlations between the morphology of the fabella and the arcuate ligament. Thus, a hard or bony fabella seemed to relate to thickening of the FF ligament. In contrast, the thicknesses of the FF and arcuate ligaments were negatively correlated. When the FF ligament was more than 5 mm thick, indicating that it was as strong as the lateral collateral ligament, no arcuate ligament could be identified. Conversely, a thin or indefinite FF ligament often accompanied a well-developed arcuate ligament (61.9%, 96/155). Our observations suggest that these ligaments act in a complementary manner to stabilize the posterolateral corner. A possible common function is fixation of the popliteal tendon on the joint capsule and lateral meniscus, rather than direct stabilization against rotation stress.

Aged↗

PubMed2004

Morphometry of the lumbar zygapophyseal facet capsule and cartilage with special reference to degenerative osteoarthritic changes: an anatomical study using fresh cadavers of elderly Japanese and Korean subjects.

Morphometric data were obtained from fresh cadaver dissections, and observations of degenerative changes in the joint cartilage (DCs) were analyzed to determine whether the morphometric parameters of the lumbar zygapophyseal joint capsule varied according to the presence and severity of DCs. There have been no previous morphometric studies of the facet capsule that describe age-related DCs. Using 23 fresh osteoligamentous lumbar spines from donated cadavers, we performed morphometric investigations of the surface areas of the joints and their capsules and measured the capsular thickness. We hypothesized that the ratio of the inner capsular area to the joint surface area for each facet (the capsule/facet index) could serve as an index showing a functional aspect of a large or small capsule. Our results showed that the joint surface area increased significantly with increasing severity of DCs, according to Grogan's classification. Facets with advanced DCs tended to have a small inner capsular surface. The capsule/facet index generally correlated positively with capsular thickness, especially the dorsal portion; however, this was not true for the ventral portion. The index also correlated negatively with DC progression. Thus, lumbar facet DCs were strongly linked to reconstructive alterations in capsular size, thickness, and looseness. The occurrence and progression of DCs narrowed the joint capsule, especially the dorsal portion, and this seemed to decrease the potential looseness of the joint. Conversely, these capsular alterations seemed to accelerate DC progression. A negative adaptation cycle seemed to occur.

Age Factors↗

PubMed2004

Comparative histology of lymph nodes from aged animals and humans with special reference to the proportional areas of the nodal cortex and sinus.

Lymph nodes are composed of a lymphocyte-rich area or cortex (subdivided into the superficial and deep cortex and the medullary cord) and another, macrophage-rich area (incorporating the subcapsular and medullary sinuses). We measured the proportional area of the cortex in lymph nodes from aged experimental mammals (rats, guinea pigs, dogs and rabbits) and elderly Japanese humans. The cervical, axillary and inguinal nodes were generally richer in cortex tissue than the pulmonary regional and mesenteric nodes. Histological heterogeneity and medullary sinus dominance were much more evident in the human nodes than in those from animals, except for the guinea pig thoracic node. Human pulmonary regional nodes were characterized by a large medullary sinus; in guinea pigs, these nodes had a similar histology but the T lymphocyte-containing areas were smaller and thinner than in humans. The paraaortic node was well developed in humans and dogs, but not in other animals tested. These species- and region-specific histological differences may influence the evaluation of experimental animal models of lymph node function, such as those recently identified for research into sentinel nodes.

Aged↗

PubMed2004

Anatomical analysis of the neurovascular bundle supplying penile cavernous tissue to ensure a reliable nerve graft after radical prostatectomy.

PURPOSE: Urologists and anatomists have disagreed concerning pelvic neurovascular bundle (NVB) structure. Recently interposition nerve grafting has been performed to improve erectile function after radical prostatectomy. To refine this procedure we reviewed NVB structure from the surgical viewpoint. MATERIALS AND METHODS: Seven fresh cadavers and serial horizontal sections from 20 formalin fixed cadavers were used for gross dissection and histological examination. RESULTS: Fresh cadaver dissections demonstrated that the pelvic splanchnic nerve (PSN) joined the NVB at a point distal or inferior to the bladder-prostate (BP) junction. Histologically hypogastric nerve fibers were much more dominant than PSN fibers at the BP junction, and the NVB, covered by the lateral pelvic fascia, became evident at levels more than 20 to 30 mm below the BP junction. PSN components joined the NVB in a spray-like distribution at multiple levels more than 20 mm distal to the BP junction. At these low levels nerves tended to be located outside of the NVB at the dorsolateral margin of the prostate. The cranial end of the mimic interposition nerve graft was directed toward the hypogastric nerve rather than the PSN. CONCLUSIONS: In contrast to general clinical opinion, the NVB appears to supply few PSN components at the BP junction with caudal PSN branches reaching the dorsolateral prostate more than 20 mm below the BP junction. This anatomy has important implications for a reliable nerve graft.

Aged↗

PubMed2004

Morphologies of the interfaces between the levator ani muscle and pelvic viscera, with special reference to muscle insertion into the anorectum in elderly Japanese.

A specific, smooth muscle-mediated interface between the levator ani muscle (LA) and the pelvic viscera has been reported. Using 110 sagittally trimmed anorectal tissue strips (80 lateral, 15 anterior and 15 dorsal specimens) obtained from the donated cadavers of 46 elderly subjects, we examined variations in the interface between the LA and the rectal muscularis propria, including the so-called conjoined longitudinal muscles. In type A (9/46), little or no tissue connected the LA to the external rectal muscularis propria, but the LA and external sphincteric mass formed a definite complex. In type B (26/46), the covering fascia of the LA changed abruptly into smooth muscles, which merged into the external rectal muscularis propria. In type C (11/46), most of the LA-associated connective tissues, composed of smooth muscles, were tightly connected to the internal and external rectal muscularis propria. These variations seemed to depend on the morphology of the recto-urethralis, the lateral extension of which reinforced the LA-associated smooth muscles sufficiently to form type B and C insertions. We also demonstrated differences in the interfacial tissues between the LA and other pelvic viscera. We hypothesize that, to avoid injury of the LA and its interfaces during strong movement of the pelvic viscera, for example during childbirth, coitus or squeezed evacuation, the pelvic connective tissue-like smooth muscles play an important role as an autonomic buffer and/or modulator of pelvic floor function. Digital examination and transrectal or transvaginal sonography may be useful for evaluating interindividual variation in these interfacial tissues in elderly patients.

Aged↗

PubMed2004

Anatomic evaluation of postural bronchial drainage of the lung with special reference to patients with tracheal intubation: which combination of postures provides the best simplification?

BACKGROUND: Although several sequences of specific postures, each corresponding to a particular lung segment, have been recommended for therapeutic bronchial drainage, these are based on little or no anatomic evidence. Moreover, because these sequences are too complex, especially for intubated patients, they require simplification. MATERIALS AND METHODS: The courses of the segmental bronchi B(1), B(2), B(1 + 2), B(3), and B(6) and their subsegmental bronchi are extremely variable. This can result in a small branching angle at the subsegmental bronchial origin. Using 106 lungs, we measured the branching angles of the subsegmental bronchi and examined their running directions in each posture of the sequences recommended for bronchial drainage. RESULTS: A small branching angle (< 120 degrees ) at the subsegmental bronchial origin was sometimes evident, and this made postural drainage difficult. Drainage of B(3) and B(6) was often difficult because they formed angles of < 45 degrees from the horizontal in certain postures (supine for B(3) and prone for B(6)). Further, we found a 45 degrees rotative prone position effective for draining B(1)a and B(6). CONCLUSION: Our anatomic findings predicted increased effectiveness in a sequence of postures: supine, 45 degrees rotative prone with left side up, 45 degrees rotative prone with right side up, and return to supine for simple, safe, and effective bronchial drainage, especially for patients with tracheal intubation. The 10 degrees right-side-up supine and 45 degrees rotative prone with head raised 45 degrees positions seemed helpful if added to the basic sequence.

Bronchi↗

PubMed2004

Variations in the tensor veli palatini muscle with special reference to its origin and insertion.

OBJECTIVE: Previous research on the tensor veli palatini muscle (TVP) has produced conflicting descriptions of its functions and topographical relationships with other orofacial structures. The goal of this study was to describe the morphology of the TVP in a systematic and comprehensive manner. METHODS: One hundred nineteen sides of 77 human heads from donated cadavers were partially dissected under a binocular microscope. Histological examination of the hard tissue-muscle interfaces was also undertaken. RESULTS: There were two adjacent origins of the TVP: the cranial base origin (CB origin) and the auditory tube cartilage origin (AT origin). The CB origin always lay anterior to the AT origin and there was no septum or loose tissue between the two muscular laminae leading from these origins. The muscle fibers converged on a central tendinous plate in the muscle belly, which gradually became a common tendon that rounded the pterygoid hamulus before inserting into the palatine aponeurosis. Notably, secondary insertions were found on the maxillary tuber (33.6%) and/or in the submucosal tissue near the palatoglossal arch (37.8%). Maxillary insertions were almost exclusively associated with an AT origin that was wide as or wider than the CB origin. Histological observations confirmed that the hamulus acted purely as a pulley and suggested that a connecting band to the tensor tympani had no or few functions of an intermediate tendon. CONCLUSIONS: The TVP appears to act as the dilator tubae and that this function can be maintained by preserving or reconstructing the maxillary insertion during push-back surgery, even if hamulotomy is necessary.

Adult↗

PubMed2003

Cantlie's plane in major variations of the primary portal vein ramification at the porta hepatis: cutting experiment using cadaveric livers.

Major variations of the primary portal vein ramifications at the porta hepatis, such as trifurcation or an anterior sectorial trunk originating from the left portal vein (L+A pattern), seem to be relatively common morphologic features, with an incidence of 10% to 30%. However, it has not been clearly demonstrated whether the usual landmarks of Cantlie's line and the middle hepatic vein (MHV) are reliable indicators of the border between the right and left liver when these variations are present. We searched for any discrepancies between the actual left/right territorial border of the intrahepatic portal vein and the usual position of Cantlie's line or the MHV course using 30 fixed cadaveric livers with major variations including hilar trifurcation and the L+A pattern. In most livers (63.3%) the usual transection plane for left/right hepatectomy was occupied by Couinaud's segment VIII (S8), and the territory of the right portal vein extended to the left of Cantlie's plane. The MHV course did not correspond with the actual border between the right and left liver. Significant rightward shift of the MHV occurred in 76.9% of livers. The severity of the discrepancy seemed to depend on the distance between the origins of the anterior and posterior sectorial trunks along the main portal vein. In conclusion, variations of the primary portal ramifications alter the segmental configurations of the liver. Our results evoke doubt over the reliability of Cantlie's line and the MHV course as landmarks for major hepatectomy when such variations are present.

Cadaver↗

PubMed2003

Evaluating the hilar bifurcation territory in the human liver caudate lobe to obtain critical information for delimiting reliable margins during caudate lobe surgery: anatomic study of livers with and without the external caudate notch.

The hilar bifurcation (HB), a wedged portion between the left and right portal vein origins, often issues the caudate branch. However, the HB territory in the caudate lobe has not been well recognized during liver surgery. In 50% of 48 human livers (25 usual livers and 23 with the external caudate notch), the HB gave off thick portal branches (> 1 mm) to supply the caudate lobe. Using minute dissections, we identified four cross-sectional configurations of three subdivisions of the caudate lobe (i.e., left, right, and HB portal territories). The HB territory was consistently located in the paracaval portion, although it sometimes (29.2%: type A) extended slightly or deeply into Spiegel's lobe. This leftward HB territorial extension was seen more frequently in livers with the notch (43.6%) than in those without it ("usual" livers) (16.0%). Moreover, in livers with the notch the caudate lobe (usually its right portal territory) tended to extend upward and rightward to attach or surround the terminal portion of the right hepatic vein. Our results suggested that in many cases subdivisions of the caudate lobe cannot be divided simply into right and left portions. The HB branch or territory should be examined to determine the real principal border as well as the subdivisional configuration of the caudate lobe. Combined evaluation of the HB branch(es) and external notch could provide critical information for anatomically sophisticated caudate lobe surgery.

Hepatectomy↗

PubMed2003

How should we treat short hepatic veins and paracaval branches in anterior hepatectomy using the hanging maneuver without mobilization of the liver? An anatomical and experimental study.

This study investigates the relevant anatomy for applying the hanging maneuver to hepatectomy by an anterior approach, where liver mobilization is not possible. Using 176 cadaveric livers, we morphometrically investigated the distribution of venous openings within the retrohepatic portion of the inferior vena cava (IVC); next, we conducted a series of experiments to identify which course for insertion of a pair of forceps preserved the thickest of these veins. After anterior dissection of the liver, we carried out an anterior incision along a plane within an area free of venous openings in the IVC. The area free of venous openings was between the thickest caudate vein and the inferior right hepatic vein (IRHV), and averaged 16.2 mm in width. When forceps were inserted along the rightward course connecting the right inferior angle of the right lobe and the same pocket-like space between the terminals of the middle and right hepatic veins, the caudate vein was very likely to be preserved, whereas the IRHV was not. In contrast, the leftward course connecting the gallbladder fossa and the pocket-like space provided an almost opposite incidence of damage. The portal territory of the hilar bifurcation was most likely to be damaged during a virtual incision along an avascular plane; however, the caudate branch of left portal origin was rarely damaged. The rightward course may be the best method for forceps insertion in cases where there is no IRHV. To preserve the caudate vein and the IRHV, taping on the right side of the IRHV and retracting to the right, or changing the direction of the forceps from leftward to rightward when the tip of the forceps is anterior to the IVC is recommended. The hanging maneuver by an anterior approach without mobilization is convenient for right or left hepatectomy for large tumors or hardened liver.

Aged↗

PubMed2003

Afferent and efferent lymph-collecting vessels of the submandibular nodes with special reference to the lymphatic route passing through the mylohyoid muscle.

BACKGROUND: Although metastasis of cancer in the oral region to the submandibular node is well described, there has been no anatomic representation of lymph vessels penetrating the oral floor and draining into the node. MATERIALS AND METHODS: Ninety specimens were obtained from formalin-fixed, donated cadavers. Histologic observations using serial sections followed the macroscopic observations. RESULTS: In 19 of 90 specimens, we found afferent collecting lymph vessels exiting from the mylohyoid surface and draining into the preglandular submandibular node. In 3 of the 19 specimens, collecting vessels passing through the narrow muscle gap with or without arteries, veins, and nerves were identified histologically. The postglandular submandibular node was not evident in the drainage route. CONCLUSIONS: Although it carries a low incidence, because of the direct lymphatic route or pathway between the oral region and preglandular submandibular node, the pathologically positive supraomohyoid node sometimes seems to be found even in elective neck dissection. However, we speculate that sentinel node investigation would reveal the much more critical role of the jugulodigastric node not only as the actual sentinel node but also as the common terminal node along the various drainage routes from the oral region.

Aged↗

PubMed2003

Configuration of the straight veins and their intramural anastomoses in the human duodenum: an anatomical study using cast specimens.

BACKGROUND/PURPOSE: There have, hitherto, been no anatomical investigations of the intramural venous system of the duodenum. METHODS: Intramural longitudinal anastomoses of the straight veins in the human duodenum were investigated, using 15 latex resin cast specimens. RESULTS: The venous tree (with a straight vein as the trunk) was developed well, with numerous twigs (venules). We identified two types of longitudinal anastomoses between the straight veins; the direct and plexus-mediated types, with an equal incidence. The direct-type anastomosis was 0.1-0.5 mm in minimum diameter along the course and communicated in almost a straight line between the mother straight veins. In contrast, the plexus-mediated type was regarded as the thickest route (almost 0.1 mm) in the suggested submucosal venular network in the duodenal wall. These two types of anastomoses were distributed almost equally in most of the duodenum, although a relatively lower density was found in the superior portion. On the ventral side of the duodenum, the thicker straight veins had anastomotic branches significantly more frequently than the thinner ones (P = 0.0018). CONCLUSIONS; These results seemed to support the feasibility of Kocher mobilization, as well as the conventional poor preservation of the duodenal venous system during duodenum-preserving surgery. However, because the intramural longitudinal venous anastomoses were limited in number and location, we recommend preservation of the posterior superior pancreaticoduodenal vein and either of the inferior venous arcades, in combination with their concomitant arteries, in exchange for the unavoidable sacrifice of Henle's trunk and the dorsal pancreatic vein.

Aged↗

PubMed2003

Anatomical study of blood supply to the spinal cord.

BACKGROUND: Low incidences of spinal cord ischemia after thoracoabdominal aortic aneurysm repair, despite sacrifice of all segmental arteries, have recently been reported. This, however, cannot be explained by previous anatomical findings, which prompted us to perform an anatomical study of blood supply to the spinal cord. METHODS: Fifty-five spinal cords from Japanese formol-fixed cadavers (mean age, 79 +/- 10 years) were studied. Diameters of the anterior spinal artery (ASA) above and below the junction with the arteria radicularis magna (ARM) and diameters of the ARM were measured using the NIH image program (National Institutes of Health Image 1.58). RESULTS: The degree of narrowing of the ASA, defined as the diameter above the ARM expressed as a percentage of the diameter below the ARM, ranged from 23% to 161% and averaged 66% +/- 30%. The degree of narrowing was plotted against the ARM diameter divided by the ASA diameter above the junction to examine the impact of the degree of narrowing on distal spinal blood flow from the ARM. The degree of narrowing was related to distal spinal blood flow from the ARM (r= 0.56, p < 0.0001). CONCLUSIONS: The degree of narrowing of the ASA varies considerably. Furthermore, distal spinal blood supply becomes progressively dependent on the ARM as the narrow point of the ASA becomes narrower. These anatomical findings of spinal blood supply should be useful for elucidating the mechanisms of spinal cord injury after repair of extensive thoracoabdominal aneurysms.

Aged↗

PubMed2003

Submucosal territory of the direct lymphatic drainage system to the thoracic duct in the human esophagus.

OBJECTIVE: To investigate how large submucosal drainage territory extends in lymphatic drainage vessels of the esophagus with and without nodal delay and which morphologies are shown when passing through the muscularis propria. METHODS: Submucosal territories of the 22 highly selected direct drainage vessels of 17 esophagi were histologically examined using transverse or sagittal serial sections. Afferent vessels from the esophagus to the subcarinal (6 esophagi) and para-esophageal (5 esophagi) nodes were also examined to identify their courses and drainage territories. RESULTS: We found the direct drainage vessel from the esophagus in 17 of 75 cadavers macroscopically (22.7%). A single submucosal drainage unit gave off 1-3 thick drainage vessels passing through a complete muscle gap of the 2 muscular layers. The unit extended longitudinally for >40 mm but was restricted to the right and/or dorsal quadrants of the esophagus. In contrast, drainage routes with a nodal relay originated from the intermuscular area, except 1 case when the adjacent or concomitant esophageal artery and vein provided the complete muscle gap. CONCLUSIONS: Due to the extended longitudinal but restricted transverse territory of the direct drainage system without a nodal relay and because of the suggested much more frequent occurrence in patients than in cadavers, when superficial carcinoma is found in the dorsal and/or right quadrants of the esophagus, we recommend detailed presurgical investigations of cervical nodes. In contrast, afferents from the esophagus to the first regional node usually seemed to be less responsible for early nodal metastasis than the direct drainage route because of their intermuscular origins.

Esophagus↗

PubMed2003

Crocodilian bone-tendon and bone-ligament interfaces.

We investigated bone-tendon (27 sites) and bone-ligament (12 sites) interfaces in six pairs of crocodile limbs and girdles under light microscopy. These crocodilian interfaces often included a direct, unmediated insertion in which the tendon or ligament fibers inserted directly into the bone itself without fibrocartilaginous mediation. This was quite different from the usual direct insertion known in mammals and lizards. Fibrocartilaginous tissue at the bone-tendon interface is generally believed to protect tendon fibers against shear stress. Other types of insertions were found in the crocodilian epiphyses, namely, hyaline cartilage and pseudofibrocartilaginous insertions. Notably, a thick periosteum/perichondrium and subchondral layer was involved at both interfaces. The thick periosteum/perichondrium seemed to form along the epiphyseal hyaline cartilage and might function in replacement of fibrocartilaginous tissues. Crocodilian thick periosteum/perichondrium would be expected to reinforce the limb and girdle bones--especially their epiphyses, in which secondary centers of ossification are absent. The subchondral layer--a kind of fibrocartilaginous tissue--seemed to play the role of the growth plate in compensating for the absence of secondary centers of ossification. Therefore, we hypothesized that the crocodile-specific bone-tendon interfaces were the result of these specializations of bone development and growth. In crocodiles, the disadvantages of the single ossification center are effectively compensated for by specialized morphologies, including these interfaces. Specialized bone growth provides the crocodile with the largest body size of the recent reptiles and an extremely fast method of locomotion.

Alligators and Crocodiles↗

PubMed2003

Gaps and fragmentation of the superficial cortex in the abdominal and pelvic lymph nodes of elderly Japanese.

Gaps and fragmentation of the superficial lymph node cortex are considered to provide intranodal shunt flow between the afferent and efferent vessels. Using serial sections of 205 nodes obtained from 27 donated cadavers more than 70 years of age, we examined the histological architecture of the abdominal and pelvic nodes in elderly Japanese. Secondary follicles were rare in the specimens. Cortex gaps were, to a greater or lesser degree, found in all nodes. We classified these nodes into three types according to how often the gap occurred. Type 1 nodes, with a relatively complete shield for the afferent lymph, were most frequently found in gastric nodes, whereas type 3 nodes, with numerous gaps, were often observed in the colic, para-aortic and pelvic nodes. The type 3 nodes showed a specific architecture characterized by a fragmented superficial cortex, three-dimensionally assembled cords and a common sinus between them. Primary follicles were located in the assembled cord structures as well as at the superficial cortex. Irrespective of the type, B and T lymphocyte areas were intermingled in the cortex-like areas. The present results reveal region-specific histological heterogeneity in aged human visceral nodes. Due to increased surface areas, the type 3 architecture seemed to accelerate systemic immunity rather than act as a local barrier in the para-aortic and pelvic nodes, which are located centrally along the lymphatic drainage routes. However, thick trabeculae often seemed to develop in the type 3 sinus to decrease nodal function with aging.

Abdomen↗