A follow-up study on the association of working conditions and lifestyles with the development of (perceived) mental symptoms in workers of a telecommunication enterprise

AIM

This study investigated the association of working conditions and lifestyle with mental health in Japanese workers.

METHODS

A follow-up study was carried out in the Kanto district of Japan of workers in a telecommunications enterprise who received their first annual health check-up between 1992 and 1996 and were between 20 and 54 years old. Workers who reported mental symptoms, had a past history of disease, or current illness at their first check-up were excluded from the analysis. In total, the study included 23 837 workers. The association between working conditions and lifestyle and the development of mental symptoms was investigated by pooled logistic regression analyses.

RESULTS

Working long hours and part-time work, as opposed to normal daytime hours of work, were factors associated with the development of mental symptoms in males, as were smoking, short sleeping hours, little physical exercise, rarely taking three meals a day, frequently eating within 1 h before sleep, much preference for salty meals and little preference for vegetables. Consumption of alcohol was negatively associated with the development of mental symptoms in males. Overall, the results suggested that the lower the Healthy Work and Lifestyle Score, the higher the risk of developing mental symptoms.

CONCLUSIONS

Working conditions and lifestyle, especially food preferences, have an apparent influence on the mental health of Japanese workers. Moreover, the Healthy Work and Lifestyle Score indicates that working conditions and lifestyle appear to have a cumulative influence upon the mental health of Japanese workers.

Influence of years engaged in agriculture and number of pregnancies and deliveries on mortality of inhabitants of the Jinzu River basin area, Japan

BACKGROUND

The occurrence of itai-itai disease is thought to be affected by such factors as pregnancy, lactation, hormonal disorders, aging, and calcium deficiency.

AIMS

To study the influence of years engaged in agriculture and number of pregnancies and deliveries on the mortality of inhabitants of the Jinzu River basin area, which has been an endemic region for itai-itai disease.

METHODS

From 6,667 participants (3,181 men, 3,486 women; participation rate 93.4%) in the 1967 health survey, 3,639 subjects (1,591 men, 2,048 women) whose years engaged in agriculture were established, and 2,559 women/2,410 women with a known number of pregnancies/deliveries were selected as the target population. These data were confirmed on the basis of self reported replies confirmed afterwards by interview. The survival survey was conducted for 6,127 days from 1 August 1967 to 10 May 1984. Subjects were divided according to three water systems: the Jinzu River, non-Jinzu River, and mixed water system; the influence on mortality of the years engaged in agriculture and the number of pregnancies/deliveries was analysed using a Cox's proportional hazards model according to the water systems.

RESULTS

The mean years engaged in agriculture and mean number of pregnancies/deliveries were not different among the three water systems. Cox's hazard ratios of these parameters to mortality were not statistically significant in the any of the water systems.

CONCLUSIONS

Neither the years engaged in agriculture nor the number of pregnancies/deliveries influenced mortality in subjects living not only in the non-Jinzu River basin but also in the Jinzu River basin using a Cox's proportional hazards model.

[[Comparison of mortality rates of elderly people in China and Japan]]

"The mortality rates and causes of death among elderly people aged sixty five and over were compared between China and Japan. The data used for comparison was China's 1990 and Japan's 1990 vital statistics. It appears that the mortality rate in China was higher than Japan. Comparing the causes of death, it was found that the death rates involving cerebrovascular diseases, malignant neoplasms and heart diseases in urban districts of China [were] higher than those in Japan. Also the death rate of people with bronchitis in rural districts was significantly higher in China.... The differences in the medical systems and life styles in China and Japan were suspected as the reasons for the differences of death rates and causes of death...." (SUMMARY IN ENG)

[Subglottic granuloma with extubating mini-trach II: report of a case]

A case of subglottic granuloma after extubating Mini-trach II is described. The patient went aorto-coronary bypass and Mini-trach II was inserted for suction of sputum. Mini-trach II was extubated 6 days after insertion. The patient complained of dyspnea 3 months later. Examination showed subglottic granuloma. First, we burned the granuloma by laser under local anesthesia. Because the visual field was not good due to vocal cord movement, we failed to resect the granuloma completely. Therefore, we performed laryngo microsurgery under general anesthesia and resected the granuloma perfectly. The patient is in good health without signs of recurrence 6 months after granuloma removal. When we used Mini-trach II, the most important issues are insertion to the cricothyroid membrane, preventing infection, and careful follow-up after removing the Mini-trach II.

Lipoprotein analysis using agarose gel electrophoresis and differential staining of lipids

We established a strategy to directly measure cholesterol and triglyceride levels of each lipoprotein fraction using a combination of agarose gel electrophoresis and differential staining. The cholesterol and triglyceride levels determined by electrophoresis correlated significantly with those of ultracentrifugation. The correlation coefficients between these methods were, for cholesterol levels 0.975(very low density lipoproteins, VLDL), 0.986(low density lipoproteins, LDL) and 0.965(high density lipoproteins, HDL) and for triglyceride levels 0.994(VLDL), 0.963(LDL) and 0.959(HDL) respectively. Both intra-and inter-assays showed low values of coefficients of variation (CV) (less than 3.57%). We observed a strong linearity between staining and triglyceride concentration. An increased VLDL-cholesterol was observed in type III subjects, a result which enabled distinction between type III and type IIb or type V lipoproteinemia. The method revealed lipoprotein patterns in some samples otherwise unexpected from their corresponding serum lipid parameters. Analyses of these electrophoretic patterns thus provide an effective technique to classify types of hyperlipidemia defined by the WHO. Furthermore, quantitative measurement of chylomicrons, usually difficult, proved to be achievable, providing an additional analysis of postprandial hyperlipidemia and the exact measurement of LDL-cholesterol after diet. Consequently, we recommend this simple and easy method for clinical evaluation of abnormalities in lipoprotein profiles.

Sickness absence and shift work among Japanese factory workers

To investigate the effect of shift work on long-term sickness absence (more than 7 calendar days), an 8-year follow-up study was carried out in a factory in Japan. The participants were male employees aged 18-54 years who were engaged in manufacturing sites. Shift patterns were classified by the number of non-daytime working days during the previous one-year. The causes of sickness absence were classified into three groups, 1) causes except injury, diseases of the musculoskeletal system and connective tissue, 2) injury, 3) diseases of the musculoskeletal system and connective tissue. The analysis of long-term sickness absences was based on the first occurrence. The age-adjusted incidence of sickness absence among shift workers who were on non-daytime shifts more than two-thirds of working days during the previous one year was significantly higher than that among other workers. After adjusting for confounding factors, a significant high risk still existed for this group of workers taking sickness absence for all causes and causes except for injury and the musculoskletal disorders. These findings suggest that shift workers who are engaged on a particular shift schedule are more likely to take leave due to sickness.

[Pulmonary granulomatous lesion with severe chest pain and hemoptysis: a case report]

We encountered a rare case of pulmonary granulomatous lesion accompanied with severe chest pain and hemoptysis. A 42-year-old man visited our hospital complaining of hemosputum. A chest radiograph showed a nodular shadow in the left lower lung field. Further examinations including fiberoptic bronchoscopy, bronchoalveolar lavage and transbronchial lung biopsy did not suggest a diagnosis. During the course of his illness, he suffered an episode of severe chest pain which could be controlled only by intravenous morphine chloride (10 mg). The chest radiograph at the time showed a broad infiltration in the left lower lung field. However, the lung perfusion scintigram taken 2 days before demonstrated decreased blood flow in the same field. We waited for the infiltration in the chest radiograph to diminish and then performed partial resection of the left lower lobe, thus terminating both hemosputum and chest pain. Histological examination showed a cavitary lesion in the periphery of the lung, surrounded by large numbers of infiltrating plasma cells and lymphocytes, among which were many hemosiderinladen macrophages. A small amount of mycelium, considered to be Nocardia or fungus, was seen in the cavity wall. These findings may indicate that an infection had contributed to the formation of a hemorrhagic granulomatous lesion, and that this lesion caused chest pain mainly because of the pleuritis and the decrease in the local pulmonary circulation.

Tortuosity of the internal carotid artery--report of three cases and MR-angiography imaging

Three cases of a tortuous internal carotid artery bulging the lateral pharyngeal wall that caused a persistent throat abnormal sensation were presented. Magnetic resonance angiography was non-invasive and useful for establishing its diagnosis. Otolaryngologists should recognize this anomaly, because it may cause a fatal hemorrhage during surgical procedures on the pharynx.

Video-assisted thoracic lobectomy by the substernal hand-assisted method for a metastatic lung tumor

In lobectomy by video-assisted thoracic surgery (VATS), the surgeon is required to have experience and a high degree of skill in performing the operation. We applied substernal hand-assisted thoracoscopic lobectomy to remove a metastatic lung tumor that originated from colon cancer in one patient and obtained satisfactory results. This method compensates for a current limitation of VATS lobectomy, namely, the fact that the surgeon cannot touch the lesion. The reported method is safe and useful for thoracoscopic surgery. It can be performed easily, even if the surgeon is not experienced in performing VATS lobectomy.

Effects of San'o-shashin-to and the constituent herbal medicines on theophylline-induced increase in arterial blood pressure of rats

San'o-shashin-to, composed of Scutellariae Radix, Coptidis Rhizoma and Rhei Rhizoma (volume ratio = 1:1:1), reduced an increase in arterial blood pressure of anesthetized rats induced by theophylline (5 mg/kg, i.v.). The hypotensive effect of San'o-shashin-to was produced in a dose dependent manner and was maximum at its 0.5 g/kg. Then the constituent herbal medicines were examined for their possible hypotensive effect. Scutellariae Radix of 0.2 g/kg slightly decreased in the blood presure. Rhei Rhizoma of 0.2 g/kg decreased in the blood pressure and the hypotensive effect was significantly produced even at the dose of 0.05 g/kg, while Coptidis Rhizoma had little effect. Among fractions of San'o-shashin-to separated by Diaion HP-20 column chromatography, the 50% methanol-eluted fraction had a large hypotensive effect. The 50% methanol-eluted fraction of Scutellariae Radix and Rhei Rhizoma were also effective and, especially, that of Rhei Rhizoma had a large hypotensive effect. In isometric tension study, Scutellariae Radix and Rhei Rhizoma (10-30 microg/ml) slightly exerted contractile and relaxant effects, respectively, on the phenylephrine-contracted endothelium-intact rat thoracic aorta. Coptidis Rhizoma (1-10 microg/ml) caused both endothelium-dependent and -independent relaxantion. These results suggest that the hypotensive effect of San'o-shashin-to is not mediated by the direct action on blood vessel but by other actions. Some components in Scutellariae Radix and Rhei Rhizoma, especially in the latter may play a main role in the hypotensive effect.

An analysis of video-assisted thoracoscopic resection for mediastinal masses in 150 cases. An overview of the pansternal approach, histology, and complications

BACKGROUND

To clarify the usefulness of the diagnosis and treatment of mediastinal masses, by video-assisted thoracoscopic surgery (VATS), we performed a retrospective multi-institutional study to delineate the type of approach, histopathology, and complications associated with these entities.

METHODS

We analyzed 150 patients who underwent the VATS procedure at several institutions between 1991 and 1999.

RESULTS

VATS resections were performed using various combinations of the "pansternal approach." The unilateral thorax approach was applied in 135 patients, the bilateral thorax approach combined with the suprasternum approach in seven patients, the unilateral thoracic approach combined with the supraclavicular approach in three patients, the infrasternal approach in three patients, and the bilateral thoracic approach combined with both the infrasternal and the suprasternal approaches in two patients. Thoracoscopic resections or biopsies diagnosed 140 benign and 10 malignant mediastinal masses. There were operative complications in nine patients (6%). Eight patients (5.3%) were converted to conventional thoracotomy.

CONCLUSION

VATS is a safe, effective, minimally invasive technique that can facilitate the resection of mediastinal masses when the pansternal approach is applied as appropriate for the location of the tumor.

Hand-assisted thoracoscopic resection for anterior mediastinal masses

We report three cases of anterior mediastinal disease (pericardial cyst, thymoma, and myasthenia gravis) in which we used a hand-assisted method in combination with thoracoscopic resection via an infrasternal approach in order to improve the maneuverability and safety of the operation. This technique combines the advantages of both thoracoscopic and incisional resection. It shows promise of becoming a less invasive operation that can be used to treat certain mediastinal tumors, both malignant and benign.

Video mediastinoscopic division of a congenital esophagobronchial fistula with esophageal diverticulum by a paraesophageal approach

We treated a patient with an esophagobronchial fistula accompanied by stomach cancer. Using an endo-stapling technique, the fistula was divided video mediastinoscopically by a paraesophageal approach through the esophageal hiatus in the diaphragm.

Thyroid clear cell adenoma with marked dilatation of membranous structures: electron-microscopic study

The electron-microscopic features of a thyroid follicular adenoma with clear cell change is described. The tumor was 7 mm in size and located in the upper portion of the left lobe of the thyroid of a 29-year-old Japanese female. Its cut surface was pale brown in color and well demarcated. The lesion consisted of solid nests with pinpoint lumina. The cytoplasm of the tumor cells was completely clear, but slightly vesicular without oncocytic change. Electron-microscopic examination revealed that the cytoplasm of the tumor cells was filled with numerous empty vacuoles. The vacuoles consisted of dilated membranous structures, indicating that they had been formed from rough endoplasmic reticulum and Golgi apparatus. There was no accumulation of glycogen, mucin, or lipid. The dilated membranous structures in the cytoplasm may be related to the increased thyroglobulin synthesis by the tumor.

Interleukin 8 and vascular endothelial growth factor -- prognostic factors in human gastric carcinomas?

Gastric carcinoma cells express potent angiogenic factors including vascular endothelial growth factor (VEGF). We previously reported that interleukin-8 (IL-8) acts as an angiogenic factor for human gastric carcinomas. More recently, we found that IL-8 upregulates matrix metalloproteinase-9 (MMP-9) expression and increases invasive activity of gastric carcinoma cells. The purpose of this study was to determine whether the expression of IL-8 and VEGF correlates with clinicopathological parameters in human gastric carcinomas. IL-8 and VEGF expression levels were measured by an enzyme-linked immunosorbent assay (ELISA) in 56 gastric carcinomas and the surrounding normal mucosa. Macroscopic and histopathological tumour findings, presence of metastasis and prognosis were obtained from the patient records and endoscopic, surgical and pathological reports. IL-8 protein levels were higher in most neoplasms than in the corresponding normal mucosal tissue. In contrast, VEGF expression in the tumours was similar to that in normal mucosa. The IL-8 level in the neoplasms correlated significantly with the depth of invasion, venous invasion and lymphatic invasion. VEGF expression in the tumours correlated well with the depth of invasion and lymph node metastasis. No correlation between IL-8 and VEGF expression in the tumours was observed. The survival rates of patients with tumours displaying high IL-8 and VEGF expression levels were significantly lower (P<0.05) than those of patients with tumours displaying low IL-8 and VEGF expression. The results suggest that IL-8 and VEGF may be independent and important prognostic factors in human gastric carcinomas.

Association between cadmium concentration in rice and mortality in the Jinzu River basin, Japan

A follow-up survey on 2101 inhabitants (1566 men, 535 women), who participated in a 1967 health survey and had resided in their present rural community since birth was conducted to determine the influence of environmental cadmium exposure on the mortality of the general population in the Jinzu River basin. The survey was conducted over 6128 days from August 1, 1967 to May 10, 1984. The rural communities were divided into two groups, one with a cadmium concentration in rice of < 0.30 ppm and the other > or = 0.30 ppm. The influence of cadmium concentration in rice on mortality was analyzed using SMRs and a Cox's proportional hazards model. In both sexes, SMRs tended to be greater in the > or = 0.3 ppm group as compared to < 0.3 ppm group. The Cox hazard ratios for males and females in the > or = 0.30 ppm group, to those in the < 0.30 ppm group, were 1.42 and 1.10, respectively (significant in the men). Since the mean cadmium concentration in rice in each rural community was closely related to the development of renal injury, in regions with high cadmium concentrations in rice, the development of renal injury induced by cadmium is believed to be the factor underlying the increased mortality observed.

A retrospective study on the relation between renal dysfunction and cadmium concentration in rice in individual hamlets in the Jinzu River basin, Toyama Prefecture, Japan

Using as an index of exposure the Cd concentration in rice and as an index of health effect the urinary abnormality rate (proteinuria, glycosuria, and proteinuria with glycosuria) in the most systematic and extensive health screening examination conducted in 1967 and 1968 in the Jinzu River basin, Japan (a total of 13,183 subjects), we investigated whether a dose-response relationship exists between the two indices. For subjects that lived in the same hamlet since birth, with low Cd concentrations in rice it was confirmed that renal dysfunction does not develop unless the length of residence is prolonged, whereas with high Cd concentrations in rice renal dysfunction develops even when the length of residence is short. For subjects that lived in the same hamlet for over 30 years and that were aged over 50 years, the urinary abnormality rate in individual hamlets showed significant increases with increases in the mean Cd concentration in rice, demonstrating that a dose-response relationship existed. The allowable values of Cd concentration in rice were estimated to be in the range of 0.05-0.20 ppm, representing values lower than the 0.4 ppm provisionally adopted by the Japanese government.

Development status of Terumo implantable left ventricular assist system

We have been developing an implantable left ventricular assist system (T-ILVAS) featuring a magnetically suspended centrifugal pump (MSCP) since 1995. In vitro and in vivo studies using a prototype MSCP composed of a polycarbonate housing and impeller (196 ml) have demonstrated long-term durability and excellent blood compatibility for up to 864 days, and excellent stability of the magnetic bearing of the MSCP. These preliminary results strongly suggested that the magnetic bearing of the MSCP is reliable and is a most feasible mechanism for a long-term circulatory assist device. We have recently devised a clinical version pump made of titanium (180 ml) with a new position sensor mechanism and a wearable controller with batteries. Cadaver fit study confirmed that the Type IV pump could be implanted in a small patient with a body surface area as small as 1.3. The in vitro performance tests of the Type IV pump demonstrated excellent hydrodynamic performances with an acceptable hemolysis rate. New position sensors for the titanium housing showed more uniform sensor outputs of a magnetic bearing than in the prototype polycarbonate pump. The Type IV pump then was evaluated in vivo in 6 sheep at the Oxford Heart Centre. Four sheep were electively sacrificed at 3 months and were allowed to survive for more than 6 months for long-term evaluation. In this particular series of experiments, no anticoagulant/antiplatelet regimen was utilized except for a bolus dose of heparin during surgery. There was a left ventricular mural thrombi around the inflow cannula in 1 sheep. Otherwise, there was no mechanical failure nor sign of thromboembolism throughout the study.

Haemorrhagic complication following percutaneous transluminal angioplasty for carotid stenosis

We report 2 cases with haemorrhagic complications following percutaneous transluminal angioplasty (PTA) for carotid stenosis. Computed tomography (CT) scanning of these cases demonstrated diffuse subarachnoid haemorrhage in 1 case, and intracerebral haemorrhage in the other case on the next day after PTA. In the latter case, we measured cerebral blood flow velocity and mean transit time with transcranial doppler (TCD) and dynamic CT scan, which demonstrated remarkable increases in the blood flow velocity and peak height, respectively. From these results, postoperative hyperperfusion was suggested to have caused haemorrhagic complications.

Rapid dephosphorylation of eIF4E by dietary protein in the skeletal muscle and liver of food-deprived rats

The effect of dietary protein on eIF4E phosphorylation was examined in rats starved for 18 h and then fed on either a 20% casein diet (20C) or a protein-free diet (0C). Refeeding with the 20C diet, but not the 0C diet, resulted in partial dephosphorylation of eIF4E in both the skeletal muscle and liver. The results suggest that the dephosphorylation of eIF4E in response to food intake was regulated by the increase in plasma amino acid concentration that occurred after feeding with the 20C diet.

Application of path analysis to urinary findings of cadmium-induced renal dysfunction

In order to identify some causal relations among various urinary indices of cadmium-induced renal dysfunction, such as glucose, total protein, amino nitrogen, beta 2-microglobulin (beta 2-m), metallothionein (MT), and cadmium (Cd), we applied path analysis method to previous epidemiological studies targeting the residents of the Cd-polluted Kakehashi River basin of Ishikawa Prefecture, Japan. We obtained a diagram-termed path model, representing some causal relations among the above urinary indices. It shows that urinary Cd is located at the beginning point in the diagram, and Cd-induced renal dysfunction develops in the following order: Cd exposure-->increase of beta 2-m and/or MT excretion-->increase of amino-N and/or total protein excretion-->increase of glucose excretion. It was proved mathematically, that in the case of both males and females, increased excretions of beta 2-m and/or MT were the most sensitive urinary indices of the early stage of chronic Cd-induced renal dysfunction.

[Special categories of elderly patients with intractable neurological diseases (NANBYO) in Toyama, Japan]

The purpose of this study was to elucidate special categories of elderly patients with intractable neurological diseases (NANBYO) in Toyama, Japan. This goal was accomplished through comparisons of data gathered in 1991 and 1997. Forty-eight (20 males, 28 females) with such diseases were recruited for the study and agreed to be interviewed. The surveys were performed by three public health center nurses. The same questionnaire was used in both years. The surveys show that the number of jobless patients and those who needed total support increased by approximately 20% from 1991 to 1997. In addition, it appears that the ratio of hospitalized patients and those who needed medical equipment installed at home increased considerably. The number of patients with caregivers increased by approximately 30%. As the caregivers got older, it was observed that the patients became more anxious about their health condition. Also, in both years, both patients and caregivers showed the highest concern about a sudden change in the patients' conditions. In conclusion, an assessment of patient and family needs is important for the development of a community health care system. It is also essential for all the parties in the field of health, medicine, and welfare, as well as volunteer groups, to have a good understanding of each other's services and to have a cooperative relationship coordinated by health centers through discussion of each individual case.