Objective: Medical information databases provide useful Real World Evidence (RWE) and a comprehensive view of medical activities. However, since each database has limited coverage and cannot be self-sufficient, combining information from multiple databases is a useful research technique. In this study, we examined methods of estimating patient numbers by combining information from multiple databases in order to assess the respective databases and identify the respective characteristics, biases and idiosyncrasies. This process also allowed us to propose improvements in the grand design of medical information databases in Japan.
Design: Retrospective observational cohort study
Methods: We attempted to estimate the numbers of patients treated for certain diseases and the numbers prescribed a drug by three methods: i) We estimated patient numbers for seven diseases using an insurance claims database, adjusting the proportion of elderly patients according to a hospital medical records database; ii) Sales information for drug X was combined with the prescribed volume per person estimated from pharmacy claims databases to estimate the number of patients administered X; this number was divided by the prescription rate obtained from a medical claims database to calculate patient numbers for the associated disease; and iii) We examined two surveys of the National Institute of Infectious Diseases (NIID) for timely estimation of patient numbers for influenza, referring to estimates from an insurance claims database.
Results: In Method i)-iii), we proved that it is possible to estimate patient numbers for many diseases and administered drugs by effectively combining multiple medical information databases. Validation could be claimed when multiple methods lead to similar results.
Conclusion: These databases provided by government agencies and private corporations are separately managed, and there is no grand plan to integrate them into one platform. It is crucial that databases, rather than being designed to stand alone, are standardized according to widely used systems under a solid master data management strategy. This will make it easier to combine information from multiple databases and to maximize their values. Mutual use of these databases by academic researchers for epidemiological and clinical studies and by government policy makers and data scientists of pharmaceutical companies may improve the usefulness of these databases and expand their application in research.

To demonstrate delayed neuro-toxicity of organophosphate, we administered 13 types of organophosphorous pesticide to hens. Initially, a screening test was performed with nine varieties of the chemical product. Later, four types were given to the fowls. Those hens dosed with S-Seven and Surecide developed ataxia and other neurophatic symptoms in the lower limbs.
After 50 days of observation, all the hens were killed and anatomized. Phathohistological examination revealed various changes in the hens that developed neuropathic symptoms: atrophy, diminution and disappearance of nerve cells in the anterior horn of the spinal cord ; edematous changes in the myelin; swelling of the neuroglia ; atrophy and vaculolar degeneration of liver cells; and necrobiosis of nepaticlobures.
It was found that these changes are closely related with the development of ataxia and doses of the chemical.
It was also found that the pathotistological changes occurred to a less extent in those hens which did not develop toxicoses.

Paraquat is one the most popular herbicides in agriculture in Japan. To study the chronic toxicological effects of paraquat on animals, rats were fed a paraquat-containing diet for 1 year and 2 months (1, 5, 25mg/kg of body weight/day). Paraquat administration induced serious histochemical changes in various organs, such as the lung, heart, kidney and liver in rast. Pulmonary fibrosis occurred in the group of rats given 1mg paraquat/kg of body weight/day in diet.
The alkaline phosphatase activity and creatinine content in the blood serum significantly increased. The concentrations of cholesterol, triglyceride and phospholipid in the serum decreased significantly.
A significant increase of lipid peroxidation was observed in the brain, kidney and liver.

Over the past eight years, small doses of an organophosphorous insecticide known in Japan as Sumithion (fenitrothion) have been administered weekly to rehsus monkeys and beagles. In this report, the results obtained during the past three years are discussed.
During the period, two monkeys and one hound died. Pathohistological examination revealed degeneration and disappearance-regeneration of liver tissues, edema of oculomotor muscle stomas, spinal cords and oculomotorius nerve fibers, and atrophy of limph nodes. These are considered the effects of the insecticide.
The surviving animals did not develop any abnormal changes or signs associated with Sumithion-induced disorders. Weight loss was not observed. Routine blood tests were negative. However, serum chemical analyses conducted in the seventh year showed that there are statistically significant differences in GPT, LDH and cholinestrase activity among the animals.

We report the case of a 76-year-old man who developed type IA endoleak through the fenestration after 1-debranch TEVAR using a Najuta endograft. The patient was admitted with expansion of the aneurysm after TEVAR, for additional therapy. Type IA endoleak through a fenestration has remained a significant clinical concern and its treatment is challenging. We performed Zone 0 TEVAR using the “Squid-Capture” technique assisted in situ stent-graft fenestration. Cerebral vessels were perfused by a percutaneous cardiopulmonary support system during in situ stent-graft fenestration, and the cerebral branch was clamped at the proximal site. It is difficult to operate the catheter inside the endoskeleton structure of a Najuta endograft, but several innovations were effective. Test dilation of the balloon catheter was performed to ensure that the wire did not interfere with the endoskeleton. Avoiding interference with the endoskeleton is important. The Squid-Capture technique allows safe and secure puncture of the graft. The operation was completed successfully. After this procedure, the endoleak disappeared. It is considered to be a useful method for treatment of endoleak through the fenestration.