Takayuki Shirakusa

Bio: Takayuki Shirakusa is an academic researcher from Kyushu University. The author has contributed to research in topics: Cancer & Endoplasmic reticulum. The author has an hindex of 4, co-authored 4 publications receiving 88 citations. Previous affiliations of Takayuki Shirakusa include Fukuoka University.

Occupational lung cancer among copper smelters

Abstract: Because a remarkably high lung cancer mortality rate was noted among males in a certain town, a case control study was carried out on the basis of mortality cards. The case group consisted of 19 males who died from lung cancer and the control group included 19 males who had died from diseases other than cancer of the lung, urinary bladder, and skin. The only significant difference between the groups was that 11 of the 19 who had died from lung cancer had been employed as smelters in a local copper refinery. Prolonged exposure to arsenic, and possibly also other compounds, seemed to be associated with cancer of the lung. The validity of the diagnosis of these lung cancer cases was also checked by blind examination of chest X-ray films of the patients with occupational cancer, a group of other lung cancer patients, and the controls. The occupational cancer was diagnosed at a higher rate than the tumors of other lung cancer cases. In all the 11 cases, the disease had become manifest after the men had stopped working at the refinery. None of them had been considered as having occupational cancer by the physicians who treated them, their previous employer, the authorities concerned, their family and friends, or indeed themselves, until this study was conducted. The necessity of a lifelong health care system for ex-smelters from copper refineries was emphasized.

Ultrastructural study of pulmonary plasma cell granuloma—report of a case

Abstract: Electron microscopy of a tumour diagnosed as a pulmonary plasma cell granuloma showed that the tumour was composed of plasma cells, fibroblasts, histiocytes and other inflammatory cells. The plasma cells were mature, with abundant endoplasmic reticulum. Fibroblasts contained multiple lipid droplets and intracytoplasmic inclusions. The relationship between plasma cell granuloma and lesions believed to be related is discussed.

A resected case of pulmonary multiple fibro-leiomyomatous hamartoma--light and electron microscopic study.

Abstract: A light and electron microscopic study of a case of multiple pulmonary fibro-leiomyomatous hamartoma is described. Like the previous reports, the patient was an old woman with no complaint. The histologic features were characterized by mingling with rich fibroblasts and mesenchymal cells. The definite diagnosis was made by the features which were detected ultrastructurally. In this case, we considered that the fibrous component was more predominant than the leiomyomatous component.

Evaluation of the Risk of Postoperative Pulmonary Complications

Abstract: Ten of 40 patients who underwent major thoracic or abdominal operations developed postoperative pulmonary complications, consisting of six massive atelectasis, three pneumonias and one edema. They were mostly thoracotomy cases and cigarette smokers. Many of these complications would have been prevented, if reliable pulmonary function tests are available to predict preoperatively such occurrence. Flow-volume curve tracing and closing volume measurement were evaluated in this respect. Both flow at the point of functional residual capacity on flow-volume curve, and the closing capacity subtracted from functional residual capacity were found to be well correlated with the occurrence of postoperative complications and can be used to evaluate the risk of pulmonary complications developing in postoperative period.

Carcinogenicity, teratogenicity and mutagenicity of arsenic.

Abstract: Arsenic may be released into the environment through industrial processes and through the generation of power from coal. It is also widely used in agriculture and was formerly used extensively in medicine. For the general population, exposure to arsenic occurs mainly through the ingestion of foodstuffs containing inorganic and organic arsenicals. Trivalent arsenicals are regarded as being primarily sulfhydryl reagents with the result they inhibit a number of thiol-dependent enzymic systems in various tissues. Arsenite also has an effect on DNA synthesis and DNA repair. Owing to its lower affinity for hydroxy and thiol groups, pentavalent arsenate inhibits fewer enzymic systems. Although there is no reliable evidence that arsenic produces tumors in experimental animals, epidemiological studies show that the incidence of epidermoid carcinomas of the skin and lungs, and of pre-cancerous dermal keratoses, is significantly increased in human subjects who have been chronically exposed to arsenic compounds by oral or respiratory routes. Arsenic appears to be one of the only teratogenic members of the Group V metals. Most of the studies performed on the mutagenic activity of arsenic have provided positive results. They involve experiments on microorganisms, plant material and Drosophila as well as observations on the ability of this metal to induce, in vitro and in vivo, chromosomal aberrations in mammalian cells.

Randomized controlled trial of prophylactic chest physiotherapy in major abdominal surgery

Abstract: Introduction This randomized controlled study evaluated the clinical benefit and physiological effects of prophylactic chest physiotherapy in open major abdominal surgery. Methods A group of 174 patients received chest physiotherapy including breathing with pursed lips, huffing and coughing, and information about the importance of early mobilization. In addition high-risk patients were given resistance training on inspiration and expiration with a mask. The resistance used during inspiration was −5 cmH2O and that during expiration +10 cmH2O. The control group (194 patients) received no information or treatment unless a pulmonary complication occurred. Results Oxygen saturation on postoperative days 1–3 was significantly greater in the treatment group. Treated patients were mobilized significantly earlier. No difference was noted in peak expiratory flow rate or forced vital capacity. Postoperative pulmonary complications occurred in 6 per cent of patients in the treatment group and in 27 per cent of controls (P<0·001). In high-risk patients the numbers with pulmonary complications were six of 40 and 20 of 39 respectively. Pulmonary complications were particularly common in patients with morbid obesity. Conclusion Preoperative chest physiotherapy reduced the incidence of postoperative pulmonary complications and improved mobilization and oxygen saturation after major abdominal surgery.

Arsenic exposure and mortality: a case-referent study from a Swedish copper smelter.

Abstract: An increased mortality from lung cancer, cardiovascular disease, haematolymphatic malignancy and cirrhosis of the liver has been reported among smelter workers and others exposed to arsenic. This study uses the case-referent (case-control) technique and is concerned with workers in a copper smelter in a complex work environment, characterised by the presence of trivalent arsenic in combination with sulphur dioxide and copper, and also with other agents. Lung cancer mortality was found to be increased about five-fold and cardiovascular disease about two-fold, showing a dose-response relationship to arsenic exposure. Mortality from malignant blood disease (leukaemia and myeloma) and cirrhosis of the liver was also slightly increased. This mortality pattern among the smelter workers is consistent with earlier reports. An increased mortality from cardiovascular disease in this type of industry is of particular interest as it has been reported only once before.

The pulmonary plasma cell/histiocytoma complex

Abstract: Twenty-seven pulmonary lesions have been reviewed both clinically and pathologically mainly by light microscopy. Almost all the lesions have shown features which were predominantly those associated with either a plasma cell granuloma or a histiocytoma. Both conditions arise from a common chronic inflammatory origin and form one disease complex. In almost every instance the lesions show some features characteristic of the other. In two malignant change had occurred. The light microscopic and electron microscopic characteristics of this complex of lung lesions are described. A possible aetiological cause is suggested. The many names that have been given to this group of pulmonary lesions in the past have led to confusion and failure to recognize their inflammatory nature.