Outbreak of chronic arsenic poisoning among retired workers from an arsenic mine in Japan.

Retired former workers of Matsuo Arsenic Mine of Miyazaki prefecture in Japan were subjected to extensive medical examination. The number of retired workers subjected to examination were 61 of 208 workers who were engaged in the works of the mine and were tracked down by the work rolls. These workers left the mine more than 15 years prior to the time of the examination. The main works in the mine were classified as mining, dressing of ores, refining, and clerical work. Several findings such as arsenodermatitis, depigmentation, performation of nasal septum, hyposmia, anosmia, and peripheral nervous disturbance attributed to exposure to arsenic were observed in 9 of 21 roasters who often worked in the arsenic kitchen. No characteristic findings of arsenic poisoning, that is, gastrointestinal disturbance, disorder of the cardiovascular system, hematopoietic disorders, or liver disturbance were observed in the retired workers. Another notable finding was that 8 cases diagnosed as pneumoconiosis were found in 18 miners.

Tricuspid valve Candida endocarditis cured by valve-sparing debridement.

This report describes the case of a patient in whom Candida albicans tricuspid valve endocarditis was treated by excision of a large vegetation and partial tricuspid valvectomy without prosthetic valve replacement. In select patients, valve-sparing debridement may allow a long-term cure and may be the procedure of choice in the treatment of Candida tricuspid valve endocarditis.

Newly developed holder for a right-angled metal venous cannula.

A newly developed holder for a right-angled metal venous cannula was developed to make direct insertion into each cava easier, especially insertion into the superior vena cava in pediatric open heart operations. We have been using this holder with ease and safety in all cases of small babies.

Trilineage response to rhG-CSF with subsequent clonal hematopoiesis in a patient with severe bone marrow aplasia.

We treated a patient with severe aplastic anemia with long-term administration of recombinant human granulocyte-colony stimulating factor (rhG-CSF). When a trilineage response of hematopoiesis was obtained after the first treatment, a chromosomal change [45XX, -7] was observed in 20 of the 20 metaphases examined. Later, we were able to show a monoclonal X inactivation pattern in the phosphoglycerate kinase (PGK) gene in the peripheral blood polymorphonuclear leukocytes and mononuclear cells, indicating the presence of clonal hematopoiesis regardless of the disappearance of the karyotype abnormality. We suggest that it is important to pay close attention to the appearance of clonal hematopoiesis during the administration of G-CSF to patients with idiopathic severe bone marrow aplasia.

Automated anatomical labeling of the bronchial branch and its application to the virtual bronchoscopy system.

This paper describes a method for the automated anatomical labeling of the bronchial branch extracted from a three-dimensional (3-D) chest X-ray CT image and its application to a virtual bronchoscopy system (VBS). Automated anatomical labeling is necessary for implementing an advanced computer-aided diagnosis system of 3-D medical images. This method performs the anatomical labeling of the bronchial branch using the knowledge base of the bronchial branch name. The knowledge base holds information on the bronchial branch as a set of rules for its anatomical labeling. A bronchus region is automatically extracted from a given 3-D CT image. A tree structure representing the essential structure of the extracted bronchus is recognized from the bronchus region. Anatomical labeling is performed by comparing this tree structure of the bronchus with the knowledge base. As an application, we implemented the function to automatically present the anatomical names of the branches that are shown in the currently rendered image in real time on the VBS. The result showed that the method could segment about 57% of the branches from CT images and extracted a tree structure of about 91% in branches in the segmented bronchus. The anatomical labeling method could assign the correct branch name to about 93% of the branches in the extracted tree structure. Anatomical names were appropriately displayed in the endoscopic view.

Tracking of a bronchoscope using epipolar geometry analysis and intensity-based image registration of real and virtual endoscopic images.

This paper describes a method for tracking the camera motion of a flexible endoscope, in particular a bronchoscope, using epipolar geometry analysis and intensity-based image registration. The method proposed here does not use a positional sensor attached to the endoscope. Instead, it tracks camera motion using real endoscopic (RE) video images obtained at the time of the procedure and X-ray CT images acquired before the endoscopic examination. A virtual endoscope system (VES) is used for generating virtual endoscopic (VE) images. The basic idea of this tracking method is to find the viewpoint and view direction of the VES that maximizes a similarity measure between the VE and RE images. To assist the parameter search process, camera motion is also computed directly from epipolar geometry analysis of the RE video images. The complete method consists of two steps: (a) rough estimation using epipolar geometry analysis and (b) precise estimation using intensity-based image registration. In the rough registration process, the method computes camera motion from optical flow patterns between two consecutive RE video image frames using epipolar geometry analysis. In the image registration stage, we search for the VES viewing parameters that generate the VE image that is most similar to the current RE image. The correlation coefficient and the mean square intensity difference are used for measuring image similarity. The result obtained in the rough estimation process is used for restricting the parameter search area. We applied the method to bronchoscopic video image data from three patients who had chest CT images. The method successfully tracked camera motion for about 600 consecutive frames in the best case. Visual inspection suggests that the tracking is sufficiently accurate for clinical use. Tracking results obtained by performing the method without the epipolar geometry analysis step were substantially worse. Although the method required about 20 s to process one frame, the results demonstrate the potential of image-based tracking for use in an endoscope navigation system.

Rheumatoid arthritis in the northeastern area of the People's Republic of China and western Japan.

The clinical features of 134 consecutive hospitalized patients with rheumatoid arthritis in the northeastern area of the People's Republic of China and 251 consecutive hospitalized patients from western Japan were compared. A total of 91.8% of the Chinese patients were of Han nationality, while all of the patients from Japan were Japanese. The patients in the People's Republic of China showed more inflammatory articular disease and more frequent subcutaneous nodules than did the Japanese patients in the presence of a less elevated ESR value and less radiographic joint destruction. The clinical features of the patients of Han nationality and the Japanese did not change even after adjusting the patients' age and disease duration. The reasons for the contradictory features in the Chinese patients still remain to be clarified. This study is hopefully a first step in promoting more precise studies on rheumatoid arthritis in the People's Republic of China.

Additive two DMARD therapy of the patients with rheumatoid arthritis.

From the beginning of 1987 to the end of 1989, 72 rheumatoid arthritis patients (RA) whose disease could not be controlled by a single disease modifying antirheumatic drug (DMARD) were selected for the trial treatment. They continued the DMARD treatment used initially at its regular dose, and then started another DMARD regimen at 1/3 to 1/2 of the regular dose as an additive DMARD treatment, which we have designated as Additive Two DMARD Therapy (ATDT). The patients were followed until the end of 1992. In the 3 months of ATDT, the effectiveness of ATDT was obtained in 42 (58.3%) patients who showed more than a 30% decrease in the initial Lansbury's activity index (AI). The rate of side effects at 3 months were 5.6%. Tiopronin, bucillamine or salazopirine added to gold sodium thiomalate or tiopronin were suggested as the recommended DMARD combinations for ATDT. The suppressive effects on AI, ESR, CRP and rheumatoid factor continued for as long as 18 to 24 months. The mean period of ATDT was 21.7 months and that at which ATDT proved useful was 31.9 months. A discontinuation of the first DMARD treatment without any following disease aggravation was obtained in 10 of 15 patients whose disease activity had been sufficiently suppressed for longer than a year. In conclusion, ATDT was suggested to be a useful way of treating RA patients whose disease activity could not be controlled by a single DMARD treatment, as well as a way of evaluating the next DMARD while the ongoing DMARD was observed to gradually lose its initial drug effect.

Methotrexate for steroid-resistant systemic lupus erythematosus.

We here report two patients with steroid-resistant systemic lupus erythematosus (SLE) who were successfully treated with methotrexate (MTX). In both cases, a steroid resistant high fever, associated with mild myositis and pancytopenia were the main common findings, and all these symptoms were alleviated within a few days either by 7.5 mg or 5 mg MTX per week. The number of CD4+ cells increased along with the clinical improvement, whereas the number of CD20+ cells and HLA-DR expressing cells also decreased. Taking into account the side effects of high dose corticosteroids and cyclophosphamides, treatment with a weekly low dose of MTX is known to contribute to an improvement in the long-term prognosis for patients with refractory SLE.

Serum interleukin-2 receptor for the early diagnosis of rheumatoid arthritis.

The value of measuring soluble interleukin-2 receptor (sIL-2R) in the sera of patients with joint pain as a predicting parameter for the future development of rheumatoid arthritis (RA) was examined. sIL-2R was measured by the ELISA method. Sixty-four patients with joint pain (suspected RA: sus-RA) but no bone or joint destruction were enrolled over 2 years and 47 were selected for the study. Eleven patients whose diagnosis was sus-RA after a year of observation were successively followed-up for 5 years. Two-thirds of the patients whose sIL-2R levels were higher than those of normal healthy adults (< 82 pmol/l; mean +2SD) developed RA within a year. On the other hand, one-quarter of the patients with normal levels of sIL-2R also developed RA within a year. The presence of two or three of the following three items in patients with joint pain without any bone and joint destruction was thus indicated to be useful for the early diagnosis of RA: elevated CRP level (> or = 1.0 mg/dl), positive rheumatoid factor (RF) (> or = 30 IU/ml) and an elevated sIL-2R level (> or = 100 pmol/l). Sensitivity and specificity were 72.7% and 96.0%, respectively. The probability of development of RA is expressed as P = 1/[1 + exp(2.673 - 0.01784 x sIL-2R - 0.4398 x CRP - 0.004835 x RF)], with R2 = 0.3083 and p<0.0005. On the other hand, the sIL-2R levels did not correlate with any future bone or joint changes within a year of observation. The above criteria may therefore hopefully justify the early treatment of patients with joint pain using drugs that can modify the patients' immune function. However, the validity of these criteria still need to be examined more thoroughly in the future.

Coexistence of ochronosis and rheumatoid arthritis.

We describe a 64-year-old female patient with ochronosis and rheumatoid arthritis. Magnetic resonance imaging of the spinal column disclosed the destruction of vertebral disks, and a bony bridging in Th12 to L2. In addition, we observed joint space narrowing in the wrists as well as among the carpal bones, positive rheumatoid factor and the presence of rheumatoid nodules, in which the histological findings were compatible with those of rheumatoid arthritis. The co-existence of these two diseases has not yet been previously reported. Pre-existing ochronotic arthropathy might have masked the manifestation of rheumatoid arthritis and made the diagnosis of rheumatoid arthritis rather difficult.

A facsimile-based graphics editing system by auxiliary mark recognition.

This paper describes a facsimile-based graphics editing system using handwritten mark recognition, and presents some experimental results with the system. In a manner different from usual graphics editors based on CRT displays and data tablets, only facsimiles are used as input and output devices in this system. As the first stage in processing, a graphic subject is first given as a set of line drawings and characters handwritten on a sheet of paper, and it is then input into the computer as a binary picture from a facsimile transmitter. Auxiliary editing information is input into the computer as handwritten marks or seal marks prepared on a separate sheet of paper. As the second stage, the marks are recognized and used to create a mark parameter list for the graphics editing. Third, referencing the mark parameter list, the graphics are expressed by using a set of graphic commands, and edited by the computer. Finally, a correct edited copy of the graphics is constructed by picture processing based on graphic commands, and it is output to a facsimile receiver. Very good results have been obtained for various kinds of hand-written graphics by using the system described here.

Blunt cardiac trauma: successful repair of right atrium rupture.

Cardiac rupture due to blunt trauma is usually fatal. We recently cared for a patient of atrial rupture without hemopericardium after MVA (Motor Vehicle Accident) which was successfully repaired, and this experience prompted this report.

Mixed connective tissue disease presenting myasthenia gravis.

We herein describe a 41-year-old female patient with an association of myasthenia gravis (MG) with anti-acetylcholine receptor (AcR) antibody, mixed connective tissue disease (MCTD) and Sjögren's syndrome (SjS). We reviewed the reported association of MG and MCTD, systemic lupus erythematosus, progressive systemic sclerosis, polymyositis and dermatomyositis, and SjS. Since we could find only two patients who fulfilled the diagnostic criteria for MCTD in the previous literature, we concluded that the association of MG and MCTD is rare. We also discuss the coexistence of SjS as one of the underlying pathological conditions for the association of MG and various connective tissue diseases including MCTD.

Hair follicle nevus with hyperplasia of smooth and striated muscle.

We report a peculiar nevus which occurred on the left side of the chin of an 18-year-old male. It had been present for four years and had grown rapidly during the last year. Histologically, many hair follicles, smooth muscles, and striated muscles were found within the reticular dermis. The hair follicles were accompanied by mature sebaceous glands; numerous eccrine glands were seen in the middle and deep dermis. Immunohistochemical stain and phosphotungstic acid hematoxylin stain supported the fact that the muscles seen between the follicles were both smooth and striated. This nevus was considered to be a hair follicle nevus accompanied by hyperplasia of smooth muscles and striated muscles.

A case of cutaneous infection by Exophiala jeanselmei.

A case of cutaneous infection by Exophiala jeanselmei is reported. The patient was a 45-year-old Japanese female. Her skin eruption consisted of a group of erythematous papules on her left cheek to which corticosteroid had been topically applied for nearly 10 years. Histopathologically, a granuloma formation was noted in the dermis within which were many brown spores. The isolated fungus was identified as Exophiala jeanselmei.

Electron microscopic study of Langerhans cell histiocytosis.

Among the several forms of Langerhans cell histocytosis (LCH), Letterer-Siwe disease is the most acute disseminated multisystemic variant. The course of Letterer-Siwe disease is usually rapid and fatal. We report here a cases of Letterer-Siwe disease which showed a good response to chemotherapy. We also describe the unusual ultrastructural findings in the histiocyte-like cells in this case.

Six cases of metastatic malignant melanoma with apparently occult primary lesions.

We report here six cases of malignant melanoma in which metastatic lesions were detected first. Of these, two cases showed some peculiar features: one exhibited widespread subcutaneous bleeding, probably due to venous rupture, and the other case had a rare primary lesion on the penis. In the Japanese literature, there have been 46 cases of malignant melanoma in which metastatic lesions were detected prior to the initial ones. The preferential site for metastasis was the lymph node (32 cases). The primary lesion was unknown in 35 patients. The outcomes were available for 36 of the 46 patients; 23 died, including 18 who died within two years.

[Seven cases of radiation-induced cutaneous squamous cell carcinoma].

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.