Gen Murakami

Detailed Histological Investigation of the Female Urethra: Application to Radical Cystectomy

PURPOSEnWe histologically examined the urethral anatomy to assess whether the surgical procedure for radical cystectomy should be modified in females.nnnMATERIALS AND METHODSnAnatomical and histological studies were performed on 20 adult female cadavers. Semiserial sections were processed for histological examination and immunohistochemistry. To assess the clinical value of the antegrade approach we examined blood loss and function in 12 consecutive patients who underwent radical cystectomy by this approach.nnnRESULTSnVaginal wall smooth muscle contributed to urethral wall formation, in addition to a thin layer of proper urethral smooth muscle, particularly when the bladder detrusor was poorly developed or degenerated. The middle urethra was attached tightly to the vaginal smooth muscles with abundant veins running at the interface. The urethral sphincter and its inferoposterior continuation (urethrovaginal sphincter) were embedded in the elastic fiber rich perineal membrane. The membrane was U shaped, wrapping around the anterior aspect of the middle urethra and extending posterior along the distal vagina to end at the lateral extension of the perineal body near the external anal sphincter. Mean estimated blood loss was 965 ml. Of patients who received a neobladder hypercontinence was observed in 14.3% and 57.1% achieved continence.nnnCONCLUSIONSnThere is topographical variation in the anatomy of tissues surrounding the female urethra. Care should be taken when dissecting the tissues dorsal or lateral to the urethra. The antegrade approach is useful since the urethra can be dissected under direct vision and traction can be applied to these structures.

Tree of Vater–Pacinian corpuscles in the human finger and thumb: a comparison between the late fetal stage and old age

Using histological sections of 12 hands from 12 human fetuses at 20–34xa0weeks of gestation (150–290xa0mm) and 14 fingers (index and small) from seven donated cadavers of elderly individuals (aged 78–95xa0years), we compared the features of Vater–Pacinian corpuscles between these two stages of life. Corpuscles with thin, tightly packed lamellae appeared to undergo a change to thick, loosely packed lamellae at 23–32xa0weeks. The typical fetal corpuscle had two parts: (1) a rod-like proximal part (0.2–0.6xa0mm in length) extending along the proximodistal axis of the finger, and (2) a distal end (0.1xa0mm) after acute bending of the proximal part. Corpuscles were associated with palmar digital nerves in the fingers, but were also present along the dorsal nerves in the thumb. A flower bouquet- or tree-like arrangement including 5–10 corpuscles extended to the dermis of the skin along a perforating artery. Serial sections of the thumb and fifth finger revealed approximately 80–180 corpuscles in the distal phalangeal segment. In elderly individuals, the corpuscles were distributed along the palmar digital nerve, but (1) their density was much lower than in fetuses and (2) a bouquet- or tree-like arrangement was rarely seen. In the distal segment, there were fewer than 40 adult corpuscles, being 0.2–0.5xa0mm thick and 1.0–2.5xa0mm long. Wavy or coiled corpuscles were evident. Because of the considerable differences in the distribution and number of corpuscles between the fetus and adult, they appear to undergo considerable depletion with age, especially along thin, superficial nerve branches.

Enteric neurons of the esophagus: an immunohistochemical study using donated elderly cadavers.

PurposeTo describe and discuss the normal anatomy and function of enteric neurons in the esophagus of aged individuals.MethodWe examined ganglion cells in esophagus specimens obtained from 15 elderly cadavers without any macroscopic pathology in the mediastinum and abdomen. Neuronal nitric oxide synthase and vasoactive intestinal polypeptide were used as parasympathetic nerve markers, and tyrosine hydroxylase as a sympathetic nerve marker.ResultsThe thoracic and abdominal esophagus contained a well-developed myenteric nerve plexus (S100 protein-positive area) in the intermuscular layer: 0.02–0.03 mm2 per 1-mm length of the circular esophageal wall. The cervical esophagus usually contained no ganglion cells. The number of parasympathetic ganglion cells was maximal in the upper or middle thoracic esophagus (mean 18–23 cells per section), whereas sympathetic cells were considerably less numerous at any sites (mean 1–3 cells).ConclusionIn comparison with previous data from elderly cadavers, the esophagus carried much fewer ganglion cells than the intestine and colon; sympathetic cells were particular less numerous. Esophageal smooth muscle exhibits a unique mode of peristalsis characterized by a rebound contraction with a long latency after stimulation. This type of peristalsis appears to be regulated by inhibitory, nNOS-positive nerves with a sparse distribution, which seems to account for the long-span peristalsis unique to the esophagus. The extreme sparsity of ganglion cells in the cervical esophagus suggests that enteric neuron-integrated peristalsis, like that in the intestine and colon, is unlikely. Surgical treatment of the esophagus is likely to change or impair these unique features.

Distance between intramuscular nerve and artery in the extraocular muscles: a preliminary immunohistochemical study using elderly human cadavers

PurposeExtraocular muscles are quite different from skeletal muscles in muscle fiber type and nerve supply; the small motor unit may be the most well known. As the first step to understanding the nerve–artery relationship, in this study we measured the distance from the arteriole (25–50xa0μm in thickness) to the nerve terminal twigs in extraocular muscles.Materials and methodsWith the aid of immunohistochemistry for nerves and arteries, we examined the arteriole–nerve distance at 10–15 sites in each of 68 extraocular muscles obtained from ten elderly cadavers. The oblique sections were nearly tangential to the muscle plate and included both global and orbital aspects of the muscle.ResultsIn all muscles, the nerve twigs usually took a course parallel to muscle fibers, in contrast to most arterioles that crossed muscles. Possibly due to polyinnervation, an intramuscular nerve plexus was evident in four rectus and two oblique muscles. The arteriole–nerve distance usually ranged from 300 to 400xa0μm. However, individual differences were more than two times greater in each of seven muscles. Moreover, in each muscle the difference between sites sometimes reached 1xa0mm or more. The distance was generally shorter in the rectus and oblique muscles than in the levator palpebrae muscle, which reached statistical significance (pxa0<xa00.05).ConclusionsThe differences in arteriole–nerve distances between sites within each muscle, between muscles, and between individuals might lead to an individual biological rhythm of fatigue in oculomotor performance.

Bladder Neck Muscle Degeneration in Patients with Prostatic Hyperplasia

PURPOSEnTo improve understanding of the variations of bladder neck musculature we investigated histological changes of the bladder neck associated with prostatic hyperplasia in adult male cadavers.nnnMATERIALS AND METHODSnWe examined histological sections from 24 donated male cadavers with a mean age of 74 years. Sections were subjected to Azan and immunohistochemical staining using desmin and S-100 antibodies. The collagen content per cross-sectional area was calculated and statistically compared.nnnRESULTSnThe existence of 3 muscle layers (submucosal longitudinal muscles, circular bladder neck muscles and external longitudinal muscles) was confirmed at the anterior and posterior regions of the bladder neck. Increased prostate volume significantly correlated with an increase in collagen fibers and thinning of muscle bundles in the anterior bladder neck. An increase in prostate volume and increasing age significantly correlated with degeneration of the posterior bladder neck muscles. As prostatic hyperplasia advanced the bladder neck muscles were progressively affected by fibrosis with the circular muscle fibers becoming thin and fragmented. In addition the severity of fibrosis associated with prostatic hyperplasia showed interindividual variation. We also devised a schematic classification of bladder neck morphology in men.nnnCONCLUSIONSnDegeneration of muscle bundles in the bladder neck of men with prostatic hyperplasia was confirmed. It was found that the bundles became thinner along with an increase in collagenous tissue. Our schematic classification of bladder neck morphology in men may be useful for further investigations.

Macrophage infiltration into thyroid follicles: an immunohistochemical study using donated elderly cadavers

To describe and discuss the morphology of the aged thyroid gland, with particular reference to the contribution of macrophages.With the aid of immunohistochemistry, we examined 1) macrophage accumulation, 2) infiltration of lymphocytes, and 3) the size and density of follicles in the unilateral lobe of the thyroid gland obtained from elderly donated cadavers (mean age, 84 years) without macroscopic malignancy. Each almost entire unilateral lobe of the thyroid showed 2554-9910 follicles per section, and each of the follicles ranged in area from 0.014-0.072 mm2. We often found evidence suggesting absorption and fusion of follicles to provide a larger colloidal lumen, containing small follicles and/or epithelial fragments. In addition to dendritic perifollicular macrophages, large and round macrophages often formed clusters in the colloid. Colloidal lumina with weak macrophage immunoreactivity were intermingled with those showing strong reactivity. Notably, a greater number of macrophage foci in the colloid was usually associated with a lower density of perifollicular macrophages. Likewise, perifollicular macrophages were not always associated with lymphocyte infiltration. In the elderly, the initial appearance of colloidal macrophages does not appear to be associated with perifollicular infiltration of mononuclear cells. Macrophage invasion into a follicle might depend on the functional state of each follicle. After destruction of a follicle, a macrophage cluster appears to remain in the perifollicular tissue, and perhaps lymphocyte infiltration occurs secondarily. This course is likely to represent the process of degeneration of the thyroid gland structure with age.

Significant Differences in Sympathetic Nerve Fiber Density Among the Facial Skin Nerves: A Histologic Study Using Human Cadaveric Specimens

Sympathetic nerve fibers in the skin nerves are connected with vasomotor, thermoregulatory, sensory input modulatory, and immunologic events; however, to our knowledge, no histological information is available for skin nerves in the human face. Using specimens from 17 donated cadavers (mean age, 86 years), we measured a sectional area of tyrosine hydroxylase (TH)‐positive fibers in (1) the frontal nerve (V1), (2) the infraorbital nerve (V2), (3) the mental nerve (V3), (4) the greater auricular nerve (C2), (5) the auriculotemporal nerve (ATN), and (6) the zygomatic branch of the facial nerve (VII). The V1, V2, and V3 were obtained at their entrances to the subcutaneous tissue from the bony canal or notch. The V1, C2, ATN, and/or VII usually contained abundant TH‐positive fibers (almost 3%–8% of the nerve sectional area), whereas the V2 and V3 consistently carried few TH‐positive fibers (<1%). The difference between these two groups was quite significant (Pu2009<u20090.001). Thus, from the superior cervical ganglion, the sympathetic nerve fibers reached the forehead through the frontal nerve trunk, whereas artery‐bounded fibers came to the cheek, nose, and mouth. The sympathetic palsy caused by trigeminal nerve involvement is mainly characterized by the symptoms seen in the distribution of the ophthalmic division of the trigeminal nerve, such as in Horners syndrome. It suggests that the forehead and the other facial areas are representative parts of those different sympathetic innervations that could be useful for evaluating the sympathetic function of the face in various diseases. Anat Rec, 299:1054–1059, 2016.

Development of the pulmonary pleura with special reference to the lung surface morphology: a study using human fetuses

In and after the third trimester, the lung surface is likely to become smooth to facilitate respiratory movements. However, there are no detailed descriptions as to when and how the lung surface becomes regular. According to our observations of 33 fetuses at 9–16 weeks of gestation (crown-rump length [CRL], 39–125 mm), the lung surface, especially its lateral (costal) surface, was comparatively rough due to rapid branching and outward growing of bronchioli at the pseudoglandular phase of lung development. The pulmonary pleura was thin and, beneath the surface mesothelium, no or little mesenchymal tissue was detectable. Veins and lymphatic vessels reached the lung surface until 9 weeks and 16 weeks, respectively. In contrast, in 8 fetuses at 26–34 weeks of gestation (CRL, 210–290 mm), the lung surface was almost smooth because, instead of bronchioli, the developing alveoli faced the external surfaces of the lung. Moreover, the submesothelial tissue became thick due to large numbers of dilated veins connected to deep intersegmental veins. CD34-positive, multilayered fibrous tissue was also evident beneath the mesothelium in these stages. The submesothelial tissue was much thicker at the basal and mediastinal surfaces compared to apical and costal surfaces. Overall, rather than by a mechanical stress from the thoracic wall and diaphragm, a smooth lung surface seemed to be established largely by the thick submesothelial tissue including veins and lymphatic vessels until 26 weeks.

CD57 (Leu-7, HNK-1) immunoreactivity seen in thin arteries in the human fetal lung

CD57 (synonyms: Leu-7, HNK-1) is a well-known marker of nerve elements including the conductive system of the heart, as well as natural killer cells. In lung specimens from 12 human fetuses at 10–34 weeks of gestation, we have found incidentally that segmental, subsegmental, and more peripheral arteries strongly expressed CD57. Capillaries near developing alveoli were often or sometimes positive. The CD57-positive tissue elements within intrapulmonary arteries seemed to be the endothelium, internal elastic lamina, and smooth muscle layer, which corresponded to tissue positive for a DAKO antibody reactive with smooth muscle actin we used. However, the lobar artery and pulmonary arterial trunk as well as bronchial arteries were negative. Likewise, arteries in and along any abdominal viscera, as well as the heart, thymus, and thyroid, did not express CD57. Thus, the lung-specific CD57 reactivity was not connected with either of an endodermal- or a branchial arch-origin. CD57 antigen is a sugar chain characterized by a sulfated glucuronic acid residue that is likely to exist in some glycosphingolipids. Therefore, a chemical affinity or an interaction might exist between CD57-positive arterioles and glycosphingolipids originating from alveoli, resulting in acceleration of capillary budding to make contact with the alveolar wall. CD57 might therefore be a functional marker of the developing air-blood interface that characterizes the fetal lung at the canalicular stage.

Early Fetal Development of the Otic and Pterygopalatine Ganglia with Special Reference to the Topographical Relationship with the Developing Sphenoid Bone: ALISPHENOID AND PARASYMPATHETIC SYSTEM

The otic and pterygopalatine ganglia are located close to the greater wing (alisphenoid) of the sphenoid bone and many researchers have noted nerves connecting these ganglia in human embryos. The greater wing (alisphenoid) arises from the cartilaginous ala temporalis independently of the lesser wing, but no topographical changes between this cartilage and nerve elements have been demonstrated. We examined histological sections of 20 human embryos and fetuses from 6 to 15 weeks of development (WD). At 6 WD, the ala temporalis, the alar process and ganglia were all identified as a single, undifferentiated cell mass. Subsequently, the two ganglia became identifiable, but were continuous on the superior side of the initial ala temporalis. The temporal, superior spine of the ala temporalis was surrounded by the part that connected the ganglia. At 7 WD, the superior spine of the ala temporalis was reduced in size and the continuity of these ganglia was lost. At this point, a secondarily‐formed communicating branch between the ganglia, the nervus sphenoidalis was first identifiable. At 9 WD, the ala temporalis and the alar process had clearly become cartilages, and the anterior end of the otic ganglion was separated from the ala temporalis. The nervus sphenoidalis became longer. At 15 WD, the otic and pterygopalatine ganglia were clear separated from the alisphenoid, which consisted of the cartilaginous ala temporalis and membranous bone. Consequently, the separation between the otic and pterygopalatine ganglia seemed to be due to the developing ala temporalis. Anat Rec, 2018.