The effect of mite antigens on murine lymphocytes and macrophages was studied in vitro. Antigens prepared from Dermatophagoides farinae bodies (Dfb) or recombinant Mag3, glutathione-S transferase (GST)-fused mite antigen, stimulated murine spleen cells to proliferate. The responder cells were B cells, because the response was sensitive to anti-Ig antibody and C treatment, but not to anti-Thy 1 antibody and C treatment. The response was not due to lipopolysaccharide contamination, a representative B cell mitogen, because polymyxin B column-passed Dfb significantly stimulated B cells, and GST protein alone did not stimulate them. Alloantigen presenting activity was increased in mite antigen-treated B cells and spleen adherent cells. Mite antigens stimulated CD80 and the major histcompatibility complex (MHC) class Ⅱ molecule expression, but suppressed CD86 expression on B cells and spleen adherent cells that were detected by a flow cytofluorometer. Antibodies to the MHC class Ⅱ molecules, CD80 and CD86 blocked the alloantigen-presenting activity. Furthermore, mite antigens stimulated B cells and spleen adherent cells to produce cytokines. These results suggest that mite antigens have a stimulating activity on antigen-presenting cells/macrophages and modulate immune responses.

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We examined dietary intakes among 69 people of three ethnic groups (Yao Chinese, Zhung Chinese and Han Chinese) in the autonomous country of Bama in China where many elderly people have a long life span in 1998. Dietary intake was evaluated using carbon and nitrogen isotope ratios of human hair (δ¹³C, δ¹⁵N) standardized by standard gas. The distributions of δ¹³C in Yao Chinese and Han Chinese were scattered from-21 to-17‰, which were close to that of C4 plants such as corn and millet. The distribution of δ¹³C in Zhung Chinese was located from-25 to-22‰, which was near that of C3 plants such as rice, wheat and potato. These values showed a much wider range when compared with δ¹³C in Chinese living in urban areas. On the other hand, δ¹⁵N in each group was distributed in the area ranged from 8 to 11‰. The result of δ¹³C was consistent with data obtained from a nutritional survey, but that of δ¹⁵N was a little higher than expected. The carbon and nitrogen isotope ratios of human hair among three ethnic groups showed characteristic distributions, although the relation between these isotope ratios and longevity is uncertain.

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Stimulated by the widespread use of head-up tilt testing, transient episodes of neurocardiogenically mediated hypotension and bradycardia have become a well recognized cause of recurrent syncope and near syncope (generally referred to as neurally mediated syncope). On the other hand, a large subgroup of patients was identified, who appeared to have a less severe hypotension and orthostatic intolerance that is characterized by postural tachycardia, exercise intolerance, disabling fatigue, lightheadedness and dizziness. This form of disability has been recognized as postural orthostatic tachycardia syndrome (POTS). While the etiology of POTS is still unclear, a mild form of idiopathic peripheral autonomic neuropathy (partial dysautonomia) or beta-receptor hypersensitivity has been suggested for the pathophysiology of this disorder. A detailed history and physical examination that includes a careful neurologic examination are essential for diagnosis. Head-up tilt testing is often useful as a standardized measure of response to postural change. This review summarizes the history, current knowledge of clinical features, diagnosis and therapeutic strategies.

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In the field of occupational health management, there are many areas in which a number of X-ray films that are associated with health checkup data for longitudinal health management of high risk groups exposed to dusts and specific carcinogenetic chemicals can be used. To make comprehensive use of the medical checkup data, we examined and evaluated basic techniques in which medical images such as radiographs can be linked to the medical checkup data in a form of computer data.
A three-step procedure system was developed based on the IS&C system which is a common specification of medical images : 1)data convert and barcode printing system, 2)film digitizing and database management system, 3)utilizing system of health checkup data including a medical image system. Experiments were done using the system and it was found that processing efficiency seemed to be less and/or varied depending on process types. It was also found that the extraction of data from existing systems and the storage methods of data onto a magnetooptical disk are special issues to be resolved in our system.

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We report 7 cases of radiation-induced skin cancer. The diagnosis was based on the history of radiotherapy for benign skin diseases (5 cases) and of occupational exposures to medical doctors (2 cases). All cases were squamous cell carcinomas which arose from chronic radiodermatitis. The estimated latent period of these tumors ranged from 6 to 64 years, with an average of 29.9 years. After surgical treatments of the lesions, no local recurrences were observed in all cases. Benign skin diseases had sometimes been treated with low-energy radiation before the 1960s. Considering the estimated latent period, the peak time point of developing risk of radiation-induced skin cancer by such treatment has been already passed, however, the danger of it should not be ignored in future. In association with multiplicity of radiation usage, occupational exposure of radiation may develop the risk of occurrence of skin cancer in future. Therefore, we should recognize that radiation-induced skin cancer is not in the past. In the cases of chronic skin diseases showing warty keratotic growth, erosion and ulcer, we should include chronic radio-dermatitis in the differential diagnosis. It is necessary to recall all patients about the history of radiotherapy or radiation exposure. Rapid histopathological examination is mandatory because of the suspicion of radiation-induced skin cancer.

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Control of tuberculosis caused by multidrug-resistant (MDR) Mycobacterium (M.) tuberculosis has become one of the major problems throughout the world. Understanding of the molecular mechanisms of resistance may help in the development of novel methods for the rapid and precise detection of drug-resistant M.tuberculosis. Eight agents have been recommended to treat tuberculosis. Isoniazid (INH), rifampicin (RFP), pyrazinamide (PZA), streptomycin (SM), and ethambutol (EB) are used as the first line agents, and the others are the second line agents. MDR M.tuberculosis strains are resistant both to INH and RFP which have the most effective bactericidal activity to M.tuberculosis. Nearly 95% of RFP resistant strains possess a mutation on the rpoB gene encoding a DNA-dependent RNA polymerase. INH particularly shows an inhibition of the cell wall synthesis of M.tuberculosis and approximately 90% of INH resistant strains have a mutation on the inhA, katG, and ahpG gene encoding enzymes related to a mycolic acid synthesis of cell wall. PZA resistant strains have a mutation on the pncA gene encoding a pyrazinamidase which degradates pyrazinamide to a bactericidal substance, pyrazinoic acid. SM resistant strains have a mutation on the rrs and rpsL gene encoding a 16S rRNA and a S12 ribosomal subunit protein, respectively. EB resistant strains have a mutation on the embB gene encoding a arabinosyl transferase which catalyzes cell wall synthesis. Resistant mechanisms of second-line agents have also been identified. Recently, rapid detection methods for RFP and INH resistant mutations have been developed on the basis of these studies.

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A symposium on protection of personal information in epidemiological research and the compilation of a cancer registry was held at the National Cancer Center, Japan, on March 16, 2000. Participants discussed the use of personal health information in epidemiological research activities such as the compiling of a cancer registry to protect personal information. Legislation in Japan is pending in the near future. A total of thirteen domestic and foreign speakers and commentators shared opinions from various viewpoints and discussed the issue. It was proposed that protection regarding personal information should be legislated as soon as possible for the development of a cancer registry; patients could be exempted from informed consent for utilization of personal health information, in particular, in public health activities such as the compilation of a cancer registry and epidemiological research with the approval of an ethics review board; ethical guidelines including these steps should be established in Japan. An appropriate system of protection of personal information should be established through constructive discussion at frequent meetings and symposia which are open to the citizenry.

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