Identification of triclosan intermediates produced by oxidative degradation using TiO2 in pure water and their endocrine disrupting activities.

The photodegradation pathways of 2-(2,4-dichlorophenoxy)-5-chlorophenol (triclosan) in water were studied. The main purposes were to identify structures of intermediates derived by radical reaction using TiO(2) advanced oxidation processes and to evaluate the endocrine disrupting activities in treated triclosan during oxidative reactions. Intermediates such as dichlorophenols, 2,8-dibenzo-p-dioxin, tetrachlorinated diphenyl ether (tetraclosan) and hydroxylated triclosan were produced by photoreaction. The estrogen, thyroid hormone and retinoid X receptor activities of the treated triclosan were measured with the yeast two-hybrid assay. It was found that tetraclosan and 2,4-dichlorophenol have stronger thyroid hormone activities than triclosan in the presence of S9.

Behavior of endocrine disrupting chemicals in Johkasou improved septic tank in Japan.

The behavior of estrogens (estrone: E1, 17beta-estradiol: E2, estriol: E3 and ethinylestradiol: EE2) and an androgen (testosterone) in the water and sludge from Johkasou in Japan was investigated. The concentrations of E1, E2, E3 and testosterone in water samples from the Johkasou were 33-500, N.D. approximately 150, N.D. approximately 6,700 and 500 ng/L, respectively. In sludge samples, the concentrations of E1, E2, E3, and testostrerone were N.D. approximately 39, N.D. approximately 6.7, N.D. approximately 60 and 0.2-9.0 ng/L, respectively. EE2 was not detected in all samples. The removal rates of E1, E2, E3 and testosterone in Johkasou were 45%-91%, 66%-100%, 90%-100%, and about 90%, respectively.

A novel recombinant adeno-associated virus vaccine induces a long-term humoral immune response to human immunodeficiency virus.

Recombinant adeno-associated virus (AAV) has attracted tremendous interest as a promising vector for gene delivery. In this study we have developed an HIV-1 vaccine, using an AAV vector expressing HIV-1 env, tat, and rev genes (AAV-HIV vector). A single injection of the AAV-HIV vector induced strong production of HIV-1-specific serum IgG and fecal secretory IgA antibodies as well as MHC class I-restricted CTL activity in BALB/c mice. The titer of HIV-1-specific serum IgG remained stable for 10 months. When AAV-HIV vector was coadministered with AAV-IL2 vector, the HIV-specific cell-mediated immunity (CMI) was significantly enhanced. Boosting with AAV-HIV vector strongly enhanced the humoral response. Furthermore, the mouse antisera neutralized an HIV-1 homologous strain, and BALB/c mice immunized via the intranasal route with an AAV vector expressing the influenza virus hemagglutinin (HA) gene showed protective immunity against homologous influenza virus challenge. These results demonstrate that AAV-HIV vector immunization may provide a novel and promising HIV vaccination strategy.

Incidence and risk factors of vascular dementia and Alzheimer's disease in a defined elderly Japanese population: the Hisayama Study.

We followed 828 nondemented residents of Hisayama Town, Kyushu, Japan, aged 65 years or older (88.3% of the elderly population) for 7 years starting in 1985 in order to determine the type-specific incidence of dementia and its risk factors in the general Japanese population. Only two subjects were lost to the follow-up, during which period 103 subjects developed dementia. Morphologic examination of the brains of 89 subjects (86.4%) was made by autopsy or CT. We made the initial diagnosis of dementia based on the DSM-III-R criteria, with the diagnoses of vascular dementia (VD) being based on the NINDS-AIREN criteria and Alzheimer's disease (AD) on the NINCDS-ADRDA criteria. The incidence of VD and AD increased with age for both sexes. The age-adjusted total incidence (per 1,000 person-years) of dementia was 19.3 for men and 20.9 for women. The corresponding rates for VD were 12.2 for men and 9.0 for women, and for AD, 5.1 for men and 10.9 for women. Among the VD subjects whose brain morphology we examined, the most frequent type of stroke was multiple lacunar infarcts (42%), but half these subjects lacked a stroke episode in their histories. Multivariate analysis showed that age, prior stroke episodes, systolic blood pressure, and alcohol consumption were significant independent risk factors for the occurrence of VD. In contrast, age and a low score on Hasegawa's dementia scale were significant risk factors for AD, and physical activity was a significant preventive factor for AD.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyperinsulinaemia and blood pressure in a general Japanese population: the Hisayama Study.

OBJECTIVES: To study the relationship between serum insulin and blood pressure, as well as the prevalence of hypertension according to the insulin level in a general Japanese population. DESIGN: In 1988 a cross-sectional community survey was conducted among Hisayama residents aged 40-79 years. METHODS: A total of 1073 males and 1407 females (72.5 and 80.5% of the total population, respectively) underwent comprehensive investigation, including a 75-g oral glucose-tolerance test. Fasting and 2-h serum insulin levels were measured by radioimmunoassay. RESULTS: The sum of the fasting and 2-h postloading insulin levels was significantly correlated with the systolic blood pressure (SBP; r = 0.18 and 0.26 for males and females, respectively) and the diastolic blood pressure (DBP; r = 0.24 and 0.19, respectively) in the subjects not receiving antihypertensive drugs. In multiple regression analysis the correlation with blood pressure remained significant in both sexes even after controlling for age, body mass index, alcohol intake, smoking, a family history of hypertension, serum total cholesterol and fasting plasma glucose. The age- and sex-adjusted prevalence of hypertension (SBP > or = 160 mmHg or DBP > or = 95 mmHg, or both, or receiving drug treatment) increased significantly with an increase in the sum of fasting and 2-h postload insulin levels in both the non-obese subjects (body mass index < 25 kg/m2) and the obese subjects (body mass index > or = 25 kg/m2). Multiple logistic regression showed that the sum of fasting and 2-h postload insulin levels was a significant factor with an independent relationship to hypertension, even after taking the other risk factors into account. CONCLUSION: The present study suggests that hyperinsulinaemia is related to hypertension in a general Japanese population.

Reversibility of cadmium-induced health effects in rabbits.

Twenty-one male rabbits were divided into three groups: rabbits of two groups were given pelleted food containing cadmium chloride at a dose level of 300 micrograms Cd/g over periods of 44 or 19 weeks. Rabbits of the last group were given ordinary commercial pelleted food and served as controls. Cadmium increased urinary protein and amino acid by week 19 and increased it to a remarkably high level by week 44. After cessation of cadmium exposure, rabbits of the first group (44 weeks exposure group) showed only little recovery from cadmium health effects: proteinuria and aminoaciduria were slightly improved. Depressed hepatic functions were also slightly improved, but did not return to the control level in 24 weeks. Fat and bone metabolism also remained depressed below the control level. Anemia did not also readily recover. On the other hand, rabbits of the second group (19 weeks exposure) recovered from the effects of cadmium: proteinuria and aminoaciduria in most animals disappeared soon after the end of cadmium exposure, plasma GPT fell after 1 week, and hemoglobin and hematocrit returned to normal in 6-11 weeks. The above results show that after cessation of cadmium exposure, mild cadmium-induced health effects were reversible in a short period, while more severe effects were not readily reversible. High performance liquid chromatographic (HPLC) profiles of renal and hepatic cadmium-thionein (Cd-MT) during and after exposure to cadmium showed no correlation to the degree of cadmium health effects, and therefore, did not help to elucidate mechanisms of the recovery from cadmium-induced health effects, probably because cadmium not bound with metallothionein (non-MT-Cd) is responsible for inducing renal effects.

Effects of dietary cadmium on rhesus monkeys.

Ten male rhesus monkeys, each weighing 3.5 kg, were divided into four groups of 3, 3, 2, and 2, and were fed daily with 100 g pelleted food containing 300, 30, 3, and 0 ppm cadmium, respectively. Urine samples were collected every 2 weeks and blood samples every 4 weeks. One monkey each of the 300 and 30 ppm groups was autopsied for pathological examination and tissue cadmium determination at the week 24 of the experiment; the remaining 8 animals were killed after 55 weeks. The lowest exposed group (3 ppm) did not show any specific biological response to cadmium over a period of 55 weeks. In the 30 ppm group, no significant changes were observed for up to 24 weeks, although cadmium concentration in the renal cortex and urine at 24 weeks were 300 mug/g wet weight and 18 mug/l., respectively. Plasma urea nitrogen and urine protein (quantitative determination) increased after 30 and 36 weeks. At 55 weeks of the experiment, qualitative tests were negative for low molecular weight proteinuria and glycosuria, and the results remained normal for renal and liver function tests and blood analysis, although cadmium concentrations in the renal cortex of two monkeys were 460 and 730 mug/g wet weight and those in the liver were 110 and 160 mug/g wet weight, respectively. In the highest exposure group (300 ppm), urine cadmium increased to 250 mug/l. by 11 weeks, and urine retinol-binding protein, plasma GOT, GPT, and LDH increased after 12 weeks. Proteinuria (quantitative determination), glycosuria, aminoaciduria (panaminoaciduria), and erythrocytopenia were observed after 16 weeks, when urine cadmium was 500-900 mug/l. Hypohemoglobinopathy and proteinuria (qualitative determination) were observed after 20 and 24 weeks, while cadmium concentrations in the renal cortex and the liver were 760 and 430 mug/g wet weight at 24 weeks, respectively. Slightly depressed tubular reabsorption of phosphate, increased urine beta(2)-microglobulin, increased plasma urea nitrogen, and increased plasma alpha(2)-globulin fraction (electrophoresis) were observed between 28 and 30 weeks of the experiment. Creatinine clearance and plasma cholinesterase decreased after 47 and 54 weeks, respectively. Cadmium concentrations in the renal cortex and the liver of two monkeys at 55 weeks were 350 and 580 mug/g wet weight and 410 and 630 mug/g wet weight, respectively. Pathological examinations revealed denaturation, destruction, and regeneration of the epithelial cells in renal proximal tubules, but no pathological changes in osseous tissues. Critical cadmium concentration in the renal cortex was estimated to be 380 mug/g wet weight for low molecular weight proteinuria and 470 mug/g wet weight for proteinuria, glycosuria, and aminoaciduria. Critical concentration in the liver was also estimated to be 210 mug/g wet weight. The apparent biological half-time of cadmium in monkeys at autopsied stage was calculated to be 0.66, 6.4, 5.2, and 22.4 years for the 300, 30, 3, and 0 ppm groups, respectively.

Malignant neoplasms in the Japanese community of Hisayama: mortality and changing pattern during a 30-year observation period based on a consecutive autopsy series.

To obtain a relatively true mortality from malignant neoplasms, we studied the frequency of cancers in the different sites and the changing patterns of the frequency and sites over time among residents of the community of Hisayama, where an autopsy-based population survey (autopsy rate, 80%) has been conducted since 191. During the 30-year period from 1962 to 1991, we found 438 malignant neoplasms in 407 cases among 1,250 consecutive autopsies. Stomach cancer was not frequent in type of cancer, with 123 cases (9.8%), followed by lung cancer in 62 (5.0%), colorectal cancer in 42 (3.4%), liver cancer in 37 (3.0%), and pancreatic cancer in 30 (2.4%). We compared the mortality from cancers for both autopsy and nonautopsy cases (the proportional mortality) among three 10-year periods. The proportional mortality from all cancers, as well as for lung, colorectal, and liver cancers, showed an increase in recent years, while stomach and pancreatic cancer showed a decrease. These figures were nearly similar to the mortality statistics for the Japanese population as a whole except for the observed decreasing trend in mortality from pancreatic cancer.

Plasma cadmium-metallothionein, a biological exposure index for cadmium-induced renal dysfunction, based on the mechanism of its action.

Thirteen rabbits were given subcutaneous cadmium (0.3 mg Cd/kg) daily. The plasma cadmium-metallothionein (CdMT) and the Cd-induced hepatic and renal functions were determined at 0, 5, 8, 11, 12, 13 and 14 weeks. Hepatic dysfunction, an elevated plasma CdMT and renal dysfunction were detected mostly between 12 and 14 weeks. The hepatic dysfunction parameters were closely related with the plasma CdMT, which was then found to correlate with the renal dysfunction parameters. All the above findings suggest the following mechanism for the Cd-induced renal dysfunction: hepatic CdMT is released into the plasma upon the Cd-induced hepatic dysfunction, and then excess plasma CdMT, whose concentration is proportional to the CdMT in the renal proximal tubular lumen, induces renal dysfunction. The critical concentration of plasma CdMT to induce renal dysfunction was estimated as 80 microg Cd/l. The plasma CdMT is proposed therefore as a biological exposure index for the Cd-induced renal dysfunction, based on the mechanism of its action.

Mechanism of hepatorenal syndrome in rats of Long-Evans Cinnamon strain, an animal model of fulminant Wilson's disease.

Rats of Long-Evans Cinnamon (LEC) strain were used as a hepatorenal syndrome model of fulminant Wilson's disease. Copper levels in the kidneys increased markedly from 16 to 126 microg Cu/g from 12 to 16 weeks, and remained at the same level at 16 and 19 weeks when the rats suffered from severe renal dysfunction and also at 20 weeks in some other normal rats. The above findings imply that the renal dysfunction may have been induced independently of the copper level in the kidneys. The present study suggested the following mechanism: immediately after copper-induced hepatic dysfunction, plasma copper-metallothionein (CuMT), which was released from the liver, became elevated. The elevation was closely related to the increases in alkaline phosphatase, glucose and amino acids, all in the urine. The above findings suggest that plasma CuMT, which was released from the liver into the blood upon copper-induced hepatic dysfunction, was subsequently filtered at the glomeruli due to its smaller molecular weight, and then caused dysfunction of the brush border membrane of the renal proximal tubules probably after splitting into radical copper and amino acids in acidic vesicles close to the membrane. The critical concentration of plasma CuMT required to induce renal dysfunction was estimated as 1 microg Cu/l.

Chronic inhalation effects of tetrachloroethylene on hepatic and renal microsomal electron transport components and delta-aminolevulinic acid dehydratase in rats.

Hepatic and renal microsomal electron transport components and erythrocyte delta-aminolevulinate dehydratase were investigated in adult male rats exposed to 0, 50, 200 and 600 ppm tetrachloroethylene for 4 weeks. Body weight and liver weight showed a significant decrease only in the 600 ppm group. A dose-dependent decrease in erythrocyte delta-aminolevulinate dehydratase was observed at 200 and 600 ppm. Serum transaminase activity (SGPT) showed an increase in the 600 ppm group only. Hepatic and renal microsomal protein content showed an increase in all groups except in the kidneys of the 600 ppm group. Induction of hepatic cytochrome b5 activity was observed in all groups. However, hepatic cytochrome P-450 showed an induction and slight inhibition at 200 and 600 ppm respectively, without any alteration at 50 ppm. Renal microsomal cytochrome P-450 activity was induced in all groups. Induction of hepatic and renal NADPH cytochrome c reductase activity was observed at 600 ppm, but no alteration was seen at 50 and 200 ppm. These results indicate that chronic inhalation of tetrachloroethylene at higher levels alters mixed-function oxidase and heme metabolism.

Ageing, a factor aggravating chronic toxicity of cadmium.

Two groups, each of 4 rabbits, 17 and 4 months old, respectively, were given s.c. administrations of cadmium (Cd) at a dose level of 0.5 mg/kg/day 6 times per week for up to 32 weeks. In 17-month-old rabbits, low-molecular-weight proteinuria appeared in the 3rd week, proteinuria, glycosuria and anemia in the 6th week; and all animals died by the 8th week. In 4-month-old rabbits, low-molecular-weight proteinuria and anemia appeared in the 6th--9th weeks, proteinuria, glycosuria and aminoaciduria by the 12th week; and all animals died by the 32nd week. The results suggest that ageing may aggravate the chronic toxicity of cadmium.

Environmental temperature, a factor modifying the acute toxicity of organic solvents, heavy metals, and agricultural chemicals.

1500 male mice, previously acclimatized to 8,22 or 38 degrees C, were used to determine the median lethal doses of organic solvents, heavy metals and agricultural chemicals by the Up-and-Down method via several routes of administration. Acute toxicity of benzene, trichloroethylene, mercuric chloride, cadmium chloride, fratol, methylparathion and dieldrin increased markedly at a low temperature of 8 degrees C, as well as at a high temperature of 38 degrees C. Acute toxicity of toluene, copper sulfate and chromium trioxide was only enhanced at a high temperature of 38 degrees C.

Does CSF copper level in Wilson disease reflect copper accumulation in the brain?

The levels of copper and ceruloplasmin in the cerebrospinal fluid (CSF) of patients with Wilson disease were investigated. Ceruloplasmin concentrations in the CSF of all patients were almost the same but were lower than those of the controls. CSF copper concentrations in patients without neurologic signs were within the normal range, 22 +/- 6 ng/ml. In contrast, CSF copper concentrations in patients with neurologic signs (69-98 ng/ml) were significantly higher than the normal levels before and at the beginning of the treatment with D-penicillamine; it gradually decreased in response to treatment. These results suggest that the appearance of neurologic manifestations in Wilson disease is not related to the CSF ceruloplasmin concentration. The CSF copper concentration in this disease appears to reflect copper accumulation in the brain and may be useful as a marker for monitoring therapy.

Erythrocyte delta-aminolevulinic acid dehydratase genotype and other mechanisms affecting workers' susceptibility to lead.

In this study, the role of delta-aminolevulinic acid dehydratase (ALAD) variants in lead susceptibility was examined. The study subjects comprised 223 male workers, and the relationship between their blood lead level and erythrocyte ALAD activity or plasma/urine delta-aminolevulinic acid level was studied. Leukocyte specimens from 11 workers, whose erythrocyte ALAD activities were as low as one-fifth that of the other normal workers, were subjected to analyses of their ALAD and ALAD alleles. Further, the entire exon fragment of the ALAD gene was analyzed by polymerase chain reaction, and the reaction product was used as a target for direct DNA sequencing. Genomic DNA analysis revealed that all 11 workers had the ALAD allele, whereas the entire ALAD gene analysis failed to indicate other variants, except for the Rsa I site. The depletion in erythrocyte ALAD activity was not found to be caused by the ALAD allele.

Upregulation of the expression of Fas antigen and Fas ligand in a human submandibular gland ductal cell line by okadaic acid.

Fas receptor is a member of a superfamily of receptors characterized by cysteine-rich motifs in the extracellular domain of the molecule. Binding of Fas ligand to the receptor leads to receptor activation and the induction of intracellular signals that result in apoptotic cell death. In the present study, the expression of mRNA and proteins of Fas receptor and Fas ligand were examined in human submandibular gland ductal (HSG) cells treated with okadaic acid by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunoblot analysis. Six hundred and eighty-two bp of the PCR product of Fas receptor mRNA was detected in HSG cells and a protein with an estimated molecular weight of 58,000 was expressed in HSG cells. Treatment of HSG cells with an agonistic anti-Fas monoclonal antibody resulted in death of HSG cells, indicating that the functional Fas receptor protein is expressed in HSG cells. Fas receptor protein expression stimulated by okadaic acid was elevated in a dose- and time-dependent manner, with maximal expression at 20 nM and 48 h treatment. Fas ligand mRNA was also detected constitutively in HSG cells by RT-PCR. Okadaic acid stimulated the expression of Fas ligand protein in HSG cells in a time-dependent manner, while the expression of the ligand was low in untreated HSG cells. The molecular weight of Fas ligand was estimated as 68,000. An antagonistic anti-Fas ligand monoclonal antibody prevented okadaic acid-induced death in HSG cells in a dose-dependent fashion as determined by WST-1 assay. The results indicate that the expression of Fas receptor and ligand is regulated by protein phosphatase(s) sensitive to okadaic acid and is involved in okadaic acid-induced apoptosis in HSG cells. The results also suggest that the Fas receptor-ligand system might regulate apoptosis in HSG cells.

Recent progress and perspectives in cadmium health effects studies.

Cadmium is a heavy metal, which is recently known to be hazardous to man. Cadmium workers have been observed to suffer from renal dysfunction and lung emphysema after long-term exposure to cadmium. However, since Itai-Itai disease, osteomalacia provoked in Toyama prefecture of Japan, was designated as a disease caused by cadmium in 1968, much attention has been paid to the health effects of residents in cadmium-polluted areas. The author described here recent progress and perspectives on cadmium health effect studies, cadmium analysis in biological samples; absorption, distribution and excretion of cadmium; health effects of residents in cadmium-polluted area; survey on the health status of Itai-Itai disease patients; beta 2-microglobulinuria; intestinal tract impairment and bone metabolism; effects on bone; effects on the liver; early diagnosis of cadmium effects; effects on future generations; carcinogenicity; critical concentration of cadmium; metallothionein; recommendations for future studies. One-hundred and sixty references are cited in this review.

Fluorometric HPLC determination of delta-aminolevulinic acid (ALA) in the plasma and urine of lead workers: biological indicators of lead exposure.

A fluorometric high-performance liquid chromatographic (HPLC) method was developed for the highly sensitive measurement of delta-aminolevulinic acid (ALA) in biological materials. By using this method, we determined ALA in the plasma and urine of 418 workers occupationally exposed to lead and in the plasma and urine of 227 controls. The concentrations of ALA in the plasma and urine of lead workers were significantly elevated as compared with those of the controls. The concentration of ALA in plasma and urine was highly correlated with that of lead in blood in lead workers. It was found that the correlation (r = 0.742) between log of plasma ALA concentrations and blood lead concentrations in lead workers was similar to that (r = 0.711) between log of urine ALA concentrations and blood lead concentrations. These results demonstrated that the measurement of ALA in plasma or in urine using a fluorometric HPLC method was useful for the biological monitoring of lead workers.

[Present status of medical care for foreigners in Tochigi Prefecture, Japan (1). Survey at all clinics and hospitals].

The number of foreign workers in Japan has rapidly increased during the last several years, because of the nation's insufficient work force. The influx of laborers into Japan has brought various issues to the forefront of society, one of the most serious being their medical care. To clarify the present status of their medical care, we sent a questionnaire to 1,004 clinics and hospitals in Tochigi Prefecture. The response rate was 55.6%, and the results are summarized as follows: 1. Clinics were rather reluctant to accept foreign patients because of the language barrier and the consequent time-consuming medical care. 2. Two-thirds of foreign patients did not enroll in any health insurance system. Most clinics and hospitals requested foreign patients with no health insurance to pay 100% of the medical cost set by the national insurance system of Japan. Some hospitals required more than 200% of the set cost, while some clinics reduced the cost. 3. Only a few doctors can communicate with patients in English. It is very difficult for doctors to communicate with foreign patients, who speak only their own native language, but not English. Most doctors felt it necessary to have the assistance of translators or booklets for translation. 4. Foreign patients endured illness, that is, ignored illness, delayed or stopped medical care at clinics and hospitals, because of communication problems and high medical costs. Labor injury cases among foreign workers were more frequent than among Japanese workers. 5. The medical cost for foreign workers per year has been estimated to be 44 billion yen (370 million dollars).(ABSTRACT TRUNCATED AT 250 WORDS)

[Present status of medical care for foreigners in Tochigi Prefecture, Japan (2). Illness behavior of foreign workers].

This study revealed certain health issues and illness behaviors of foreign workers living in Tochigi Prefecture, Japan. We collected responses to our questionnaires from 317 foreign workers from 41 factories. The results are summarized as follows: 1. The incidences of signs and symptoms of poor health were high among foreign workers. Most signs and symptoms seemed to be related to physical and psychological stresses in daily life and work. The incidences of work-related injury and disease were also high. 2. A quarter of the foreign workers polled did not visit clinics or hospitals regardless of their suffering from severe illness, mainly because of heavy work duties, language barriers and high medical costs. 3. Foreign workers most often visited clinics, pharmacies and hospitals, when they suffered from illness. They would not pay more than 10,000 yen for an outpatient medical visit or 100,000 yen for admission or for total medical costs. 4. Sixty percent of foreign workers had difficulty in communicating with doctors, even in English. This situation made foreign workers hesitant to visit clinics and hospitals in Japan. 5. Forty percent of foreign workers did not enroll in a health insurance system, but half of them felt it was necessary to do so. 6. Fifty-four percent of foreign workers were psychologically unstable. Emergency psychological care should be applied in some cases, such as potential suicide cases.