Immunohistochemical and immunoelectron microscopical characterization of cerebrovascular and senile plaque amyloid in aged dogs'' brains

Immunohistochemical and immunoelectron microscopical studies were carried out on 28 aged dogs' brains. Amyloid deposits were seen in the arteries and capillaries in the leptomeninges and in superficial areas of the cortices in 19 (67.9%) of the 28 dogs (10-22 years of age). Immunohistochemically, these amyloid deposits were reactive for anti-beta/A4 antibody. Additionally, a variable number of parenchymal deposits with diffuse beta/A4-immunoreactivity (diffuse plaques) was also noted throughout the cerebral cortex in 24/28 dogs (85.7%). However, these plaque lesions were undetectable in Congo red staining. Electron microscopically, amyloid fibrils, measuring 10 nm in width, were located mainly in the tunica media of the arteries, and in less involved vessels they tended to be present among collagen fibres in the adventitia and smooth muscle cells in the outer layer of the media. The plaque lesions appeared to contain sparse aggregations of amyloid fibrils. In immunoelectron microscopical examinations, all amyloid fibrils in both blood vessels and plaques were selectively labelled by gold particles. These findings indicate that aged dogs can provide a useful experimental model for research into the beta/A4-type of cerebral amyloidosis commonly seen in Alzheimer's disease.     

Permanent prostate brachytherapy for Japanese men: Results from initial 100 patients with prostate cancer

OBJECTIVE: To evaluate the initial results of brachytherapy for prostate cancer with permanent iodine-125 implant in Japan. METHODS: The results obtained with brachytherapy in the initial 100 Japanese patients treated at Nagano Municipal Hospital were reviewed. Patients with a prostate-specific antigen (PSA) level of less than 10 ng/mL and a Gleason's scores of 5, 6, 3 + 4 were classified as having a low risk of recurrence. Patients with a PSA level of 10-20 ng/mL and/or a Gleason's score of 4 + 3 were classified as having an intermediate risk for recurrence. Seventy-eight of the low-risk patients and 19 of the intermediate-risk patients were treated by seed implants alone, or seed implants combined with preceding external radiation, respectively. A total of 53 patients received neoadjuvant hormone therapy. The efficacy and morbidity of brachytherapy were investigated using the serum PSA, International Prostate Symptom Score, quality of life score and uroflowmetry data. RESULTS: The average V100 and D90 obtained by post-implant dosimetry was 94.3 and 113.7%, respectively. Serum PSA decreased gradually after treatment, although it had still not reached a nadir after 1 year. There was little difference of the PSA level between the patients with and without neoadjuvant hormone therapy even at 1 year after seed implantation. There were no PSA biochemical failure or clinical recurrence during the follow-up period. Voiding symptoms worsened until 3 months after treatment, and then gradually improved. Acute urinary retention occurred transiently in one patient (1%). Rectal bleeding and severe diarrhea did not occur. CONCLUSION: Brachytherapy is a feasible and effective option for the treatment of prostate cancer in Japanese men. Brachytherapy may have a different effect in Japanese patients with respect to voiding symptoms. Urinary retention was rare, but voiding symptoms were persistent in Japanese patients. Neoadjuvant hormone therapy deserves investigation to determine whether it can achieve better results, especially in patients with an intermediate risk.     

Venous hemangioma of the mesoappendix: Report of a case and a brief review of the Japanese literature

We present herein the rare case of a 48-year-old man in whom an abdominal mass, revealed by celiotomy to be a solid tumor of the mesoappendix, was histologically diagnosed as having a venous hemangioma. To our knowledge, only 18 cases of mesenteric hemangioma have been reported in Japan, including the present case. However, establishing a correct diagnosis preoperatively is extremely difficult despite advanced imaging techniques. In fact, a mesenteric mass was diagnosed preoperatively in only 3 of these 18 cases. Complete excision with or without bowel resection was performed in 16 cases. Interestingly, the histological diagnosis of all the previous cases was cavernous hemangioma, confirming that this report decuments the first case of venous hemangioma of the mesentery in the Japanese literature.     

Clinical evaluation of 123I-MIBG for assessment of the sympathetic nervous system in the heart (multi-center clinical trial)

Multi-center clinical trial of 123I-metaiodobenzylguanidine (123I-MIBG) was carried out to assess its utility as a scintigraphic imaging agent reflecting sympathetic neuronal function in cardiovascular field. Studies were performed on patients with heart diseases of three categories, myocardial infarction, angina pectoris and cardiomyopathy. Scintigraphic images, reflecting sympathetic neuronal function were obtained with 123I-MIBG from all of those categories of patients and the efficacy of the imaging was revealed in 781 (95.0%) out of 822 patients. In some patients abnormality was suggested in sympathetic neuronal function with 123I-MIBG imaging, in spite of normal findings with myocardial perfusion scintigraphy by 201TlCl. In all 981 patients studied with 123I-MIBG, there have been no severe adverse reactions, except complaints of burning on injection site of the agent or nausea, etc. from 4 patients. We conclude that 123I-MIBG imaging is one of the effective tools for diagnostic use reflecting topical sympathetic neuronal function in the heart, judging from its safety and efficacy.     

Morphological observations of the apical surface of chick retinal pigment epithelium

Chick embryonic retina was examined in order to investigate morphological changes of the apical portion of retinal pigment epithelial (RPE) cells. Whole retina and RPE sheets were observed by fluorescence microscopy (rhodamine-phalloidin preparation) and transmission electron microscopy. Photoreceptor cells had no inner and outer segments on the 8th day in ovo. The inner segments have been formed on the 15th day and the outer segments on the 19th day. RPE sheets had short and blunt apical processes on the 8th day, elongated and slender ones on the 15th day, and well-developed and melanin-containing processes on the 19th day. RPE of the 19th day had numerous bundles of actin filaments associated with melanin pigments in the basal portion of the apical processes and in the apical cytoplasm. In rhodamine-phalloidin preparations, intense fluorescence was localized in the RPE apical processes and cytoplasm on the 19th day. We concluded that RPE apical processes develop in accordance with the photoreceptor development.     

Case of Parkinson's disease presenting with unique dyspneic attacks caused by oromandibular dystonia and sleep apnea syndrome]

A 79-year-old woman with a 4-year history of Parkinson's disease was admitted due to unique dyspneic attacks with cyanosis while eating. Dyspneic attacks with cyanosis occurred mainly during actions such as taking meals or rehabilitation. Due to increased tonus of the orbicularis oris muscle, she was unable to open her mouth and breathe out, and finally experienced hypoxemia as revealed by pulse oxymetry. Dystonic hypertonus was relieved by touching the mandible with the fingers, and she was able to open her mouth again. These symptom was compatible with the sensory trick. Based on these findings, we considered that dyspneic attacks were produced by focal oromandibular dystonia. Polysomnography also showed central sleep apnea. We report herein a rare case of Parkinson's disease presenting with respiratory insufficiency caused by focal dystonia and central sleep apnea.     

Changes in Glucose Metabolism in Cerebral Cortex and Cerebellum Correlate With Tremor and Rigidity Control by Subthalamic Nucleus Stimulation in Parkinson's Disease: A Positron Emission Tomography Study

Objective. Employing [¹⁸F]fluorodeoxyglucose (FDG) positron emission tomography (PET) to assess the correlation between the effect of deep brain stimulation (DBS) on the subthalamic nucleus (STN) and the regional cerebral metabolic rate of glucose (rCMRGlc) in advanced Parkinson's disease patients (N = 8). Materials and Methods. On the basis of patients’ diary records, we performed FDG‐PET during the off‐period of motor activity with on‐ or off‐stimulation by STN‐DBS on separate days and analyzed the correlation between changes in motor symptoms and alterations in the rCMRGlc. Result. When FDG‐PET was performed, the motor score on the unified Parkinson's disease rating scale (UPDRS) was 64% lower with on‐stimulation than with off‐stimulation (p < 0.001, Wilcoxon single‐rank test). STN‐DBS increased the rCMRGlc in the posterior part of the right middle frontal gyrus, which corresponded to the premotor area, and the right anterior lobe of the cerebellum (p < 0.005, paired t‐test). No region exhibited a decrease in rCMRGlc. Among the items of the UPDRS motor score, the changes in resting tremor and rigidity of the left extremities showed a significant correlation with the changes in rCMRGlc observed in the right premotor area (p < 0.02 and p < 0.05, respectively, Spearman's rank correlation). Conclusions. STN‐DBS either activates the premotor area or normalizes the deactivation of the premotor area. These FDG‐PET findings obtained are consistent with the idea that STN‐DBS modifies the activities of neural circuits involved in motor control.