Akitomo Shimoji

The relationship between senile plaques and cerebral blood vessels in Alzheimer's disease and senile dementia. Morphological mechanism of senile plaque production.

SummarySeveral kinds of senile plaque found in 6 brains (4 from patients with Alzheimer’s disease and 2 from patients with senile dementia) were examined in serial sections by light electron microscopy. The results obtained were as follows.All the senile plaques contained at least some amyloid fibrils, and these seemed to be produced at the basement membranes of capillary endothelial cells and projected into the surrounding parenchyma.Even when the senile plaques themselves appeared to lack amyloid fibrils by light microscopy, at least one degenerable capillary containing amyloid fibrils was demonstrabled when serial sections were examined ultrastructurally.The findings described above suggest that the amyloid fibrils which form the cores of the several kinds of senile plaque, seem to be produced at the basement membrane of the endothelial cell. It is speculated that the capillary degeneration with the formation of amyloid fibrils may be primary change in the genesis of senile plaques.

Ultrastructural studies of amyloid fibrils and senile plaques in human brain.

SummaryAmyloid fibrils and senile plaques in brains with Alzheimers disease, senile dementia and Downs syndrome were examined by light and electron microscopy. In addition, replicas of amyloid fibrils, made by a quick freezing method from a brain with Downs syndrome, were examined. All amyloid masses forming the cores of senile plaques consisted of numerous amyloid fibrils spreading from the walls of small blood vessels to the surrounding parenchyma. The amyloid fibrils ran in various directions, forming bundle-like groups in a geometrical array. They appeared as rods with hollow structures consisting of an array of globular units in the replicas, while they showed bead-like structure in the tissue specimens of 500-nm thick sections. The ultrastructure of replicas reveals a new finding on the structure of amyloid fibrils in the human brain.

Wilson's Disease with Extensive Degeneration of Cerebral White Matter and Cortex

Abstract: This is a report of an autopsy case of Wilsons disease with widespread degeneration of the cerebral cortex and white matter, the basal ganglia and thalamus and, to a lesser degree, the cerebellum and brain stem. The patient was a 28‐year‐old man at the time of death with the clinical course of a 20‐year duration.

Ultrastructural Changes of Blood Vessels in the Cerebral Cortex in Alzheimer's Disease

Abstract: Several parts of the cerebral cortices in five brains from patientswith Alzheimers disease were examined by light and electron microscopes. The results obtained are as follows:

Culture-bound syndrome and a culturally sensitive approach: from a viewpoint of medical anthropology.

Abstract Some aspects of the culture‐bound syndrome are presented for discussion. From the psychiatric and medical anthropological viewpoints, kamidaari is described as an initiatory illness for seeing a shaman, and focus on clinical realities developing between different therapeutic subcultures in the same culture and the complementary practices of two epistemological ones, namely, the shamanistic and modern psychiatric system in the shamanistic climate. It is suggested that the culture‐bound syndrome that reflects cultural influences on disease patterns and renders them difficult to place in a universal classificatory system should be seen as a vernacular bricolage or as tactics used by people within the web of their own local culture of origin. Therapists who treat patients in a cross‐epistemological milieu should be aware of the subcultural‐epistemological issues that may affect the clinical process. It should be recognized that, depending on the nature of a particular psychiatric crisis, the clinical encounter is straddling the boundaries of multiple clinical realities. At every stage in the clinical field, there is an intersection, consonance, or interruption of rejoinders in the open dialog by all those engaged in the clinical time. Aspects of climatic, culturally sensitive psychotherapy will be described, and the concept of the culture‐bound syndrome will be reconsidered. Our approach could be seen as ‘situation‐ and fudo‐bound’.

Mediation between the shamanistic model and the psychiatric model in a shamanistic climate: A viewpoint of medical anthropology

Abstract  It is suggested that any clinician working on the Miyako islands, Okinawa, Japan, be a mediator or a negotiator between two worlds, namely the shamanistic and the modern psychiatric ones. On these islands, to subscribe to either is possible only by ignoring conflicting clinical realities. The main point is to summarize the complementary practices of these two medical systems on these islands. Psychiatric illness attributed to kamidaari is introduced. The initiatory illness for seeing a shaman is called kamidaari or kamburi. From the viewpoint of medical anthropology, aspects of the treatment of such patients in a shamanistic ‘climate’ (which is called fudo in Japanese), will be reported. In the shamanistic fudo, it must be recognized that, at a critical moment, shamanistic epistemology and psychiatric epistemology penetrate each other, and they exist together in a clinical ‘mesh’. Two epistemologies must join in a coalition to access, and build continuity into, psychiatric and shamanistic medical care. It is demonstrated that these two worlds almost merge in dialogue but do not fuse, and that clinical relations occur on the boundary between these two epistemologies. ‘Climatic’ specific therapeutic stances are introduced and are clinically illustrated.

Fine structure of inclusion body in the nucleus of Alzheimer glia type II in the brain of hepatocerebral degeneration

SummaryBests carmine positive inclusion bodies in the nuclei of Alzheimer glia type II were observed diffusely in the brain with a special type of hepatocerebral degeneration. These inclusion bodies were examined with an electron microscope. The results showed that a body consisted of β-glycogen particles, amylopectin-like substances, and capsules enveloping glycogen particles.It was speculated that the inclusion body is produced and accumulated in the nucleus by the disturbance of glycogen metabolism in the nucleus itself.

Pathological Findings of the Sural Nerve in Mitochondrial Encephalomyopathy

Abstract: We examined the muscle and peripheral nerve of a 55–year‐old woman with familial mitochondrial encephalomyopathy. In the gastrocnemius muscle, many ragged red fibers and mitochondria containing paracrystalline inclusions in those fibers were observed by light and electron microscopy, respectively. Histopathological studies of the sural nerve revealed a marked decrease in the number of large myelinated fibers. Electron microscopic studies showed an accumulation of glycogen particles and mitochondria containing abnormal, structurally obscure cristae in the Schwann cell cytoplasm. These results suggest that the cause of loss of the large myelinated fibers may be some disturbance of metabolism in the Schwann cells due to mitochondrial dysfunction.

Histopathological Changes Induced by Disturbance of Microcirculation in the Rat Brain

Abstract: Microcirculatory disturbance was induced in 8 rats after injecting micro‐sphere latex (5 micron in diameter) from the right carotid artery.

Morphological Observations of Peripheral Nerves by the Scanning Electron Microscope

Abstract: In order to observe a normal peripheral nerve and a changed peripheral nerve by means of a scanning electron microscope, the present study was carried out. In the changed nerve fibers, they were enveloped by many processes of hypertrophied Schwann cells, and the processes of the Schwann cells seemed to make a pseudosyntitium‐like structure with each other. From this finding, it was speculated that these Schwann cells seemed to follow the reverse process in the development of normal peripheral nerve fibers.