Sumire Inaga

Application of low-vacuum scanning electron microscopy for renal biopsy specimens

Low-vacuum scanning electron microscopy (LV-SEM) has been developed which enables the observation of soft, moist, and electrically insulating materials without any pretreatment unlike conventional scanning electron microscopy, in which samples must be solid, dry and usually electrically conductive. The purpose of this study was to assess the usefulness of LV-SEM for renal biopsy specimens. We analyzed 20 renal biopsy samples obtained for diagnostic purposes. The sections were stained with periodic acid methenamine silver to enhance the contrast, and subsequently examined by LV-SEM. LV-SEM showed a precise and fine structure of the glomerulus in both formalin fixed paraffin and glutaraldehyde-osmium tetroxide-fixed epoxy resin sections up to 10,000-fold magnification. The spike formation on the basement membrane was clearly observed in the membranous nephropathy samples. Similarly to transmission electron microscopy, electron dense deposits were observed in the epoxy resin sections of the IgA nephropathy and membranous nephropathy samples. LV-SEM could accurately show various glomerular lesions at high magnification after a simple and rapid processing of the samples. We consider that this is a novel and useful diagnostic tool for renal pathologies.

Aerosol droplet delivery of mesoporous silica nanoparticles: A strategy for respiratory-based therapeutics

UNLABELLED A highly versatile nanoplatform that couples mesoporous silica nanoparticles (MSNs) with an aerosol technology to achieve direct nanoscale delivery to the respiratory tract is described. This novel method can deposit MSN nanoparticles throughout the entire respiratory tract, including nasal, tracheobronchial and pulmonary regions using a water-based aerosol. This delivery method was successfully tested in mice by inhalation. The MSN nanoparticles used have the potential for carrying and delivering therapeutic agents to highly specific target sites of the respiratory tract. The approach provides a critical foundation for developing therapeutic treatment protocols for a wide range of diseases where aerosol delivery to the respiratory system would be desirable. FROM THE CLINICAL EDITOR Delivery of drugs via the respiratory tract is an attractive route of administration. In this article, the authors described the design of mesoporous silica nanoparticles which could act as carriers for drugs. The underlying efficacy was successfully tested in a mouse model. This drug-carrier inhalation nanotechnology should potentially be useful in human clinical setting in the future.

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