Toshio Kameie

Scanning and transmission electron-microscopic study of the development of the podocyte in the human fetus

Abstract. The metanephric kidneys of seven human fetuses at 11 – 17 weeks’ gestation were examined by scanning and transmission electron microscopy in order to evaluate differentiation of glomerular podocytes. When glomeruli were in the stage of S-shaped bodies, the surface of the visceral epithelium of renal corpuscles was smooth, with indistinct cell borders. As the glomeruli developed, visceral epithelial cells of renal corpuscles became spherical and resembled clusters of grapes in dense aggregation. In this stage, processes and foot processes were simultaneously formed at the base of epithelial cells. As glomeruli further differentiated, visceral epithelial cells of renal corpuscles began to separate from one another and became flat with the development of vascular loops. Processes and foot processes were exposed for the first time in Bowman’s space. In this stage, the degree of differentiation of epithelial cells varied widely among various sites of the glomerulus. As glomeruli developed further, projections became more complex and epithelial cells began to show structures similar to those of adult epithelial cells. The adjacent foot processes arose from different cells throughout the period of morphological differentiation.

Thoracic insufficiency syndrome in an elderly patient: An autopsy case

To the Editor: Primary chest wall deformities and/or scoliosis can affect normal lung development and growth and, consequently, pulmonary health and quality of life. This condition is referred to as thoracic insufficiency syndrome (TIS), which is primarily characterized by the inability of the thorax to support normal respiration or lung growth. TIS includes various disparate disorders that have the potential to limit respiration (e.g., congenital thoracic deformity and chest surgery complications). An effective surgical treatment modality for TIS, known as the vertical expandable prosthetic titanium rib (VEPTR), has been developed to promote the development of the lung and thorax. In this paper, we focused on the clinical and pathological findings of thoracic deformity and lung pathology in an elderly TIS patient to reveal the pathogenesis of TIS with congenital thoracic deformity and the condition of elderly TIS patients without proper surgical treatment. The body of an 81-year-old Japanese woman who had succumbed to pneumonia was subjected to autopsy during an anatomical dissection class for medical students at Tottori University. The medical history of this patient was unavailable. No surgical scar was observed anywhere on the body surface. Dissection of the anterior chest wall showed thinning of the left pectoralis major muscle compared with the right one and deformation of the first four ribs in the left thorax (Fig. 1a,b). A small cervical rib was fused with the first rib, and they were branched and connected with the sternum as the first and second costal cartilages. The second and third ribs were fused and connected with the sternum as the third costal cartilage. The fourth rib showed sigmoid deformity, leading to widening of the fourth intercostal space. Interestingly, the posterior parts of the first, second, and third ribs did not correspond with the respective anterior parts, and the deformity in the first four ribs was primarily localized between the midclavicular and posterior axillary lines. Dissection of the back revealed thoracic levoscoliosis, asymmetry of the scapulae, and incomplete formation of the inferior part of the left trapezius muscle. The length of the right and left scapulae between the superior and inferior angles was 15 and 13 cm, respectively. The inferior angle of the left scapula had invaginated into the widened fourth intercostal space. Dissection of the thorax showed that, because of the deformity in the first four ribs and the thoracic levoscoliosis, the left thoracic cavity was significantly restricted. Consequently, the left lung was markedly flattened and weighed only 110 g, although it was separated into the upper and lower lobes by the oblique fissure. The maximum thickness of the left lung was 10 mm near the hilum and <5 mm at the periphery. The right lung, however, was enlarged, extended over the vertebral column to the left side, and weighed 680 g; it showed a normal anatomy of three lobes and two fissures. Pleural effusion was not observed. Histological examination showed that in the flattened left lung, alveolar tissue was mainly replaced by fibrous tissue with moderate inflammatory infiltration. The periphery of the