Muneko Nishijo

Kanazawa Medical University, Kanazawa, Ishikawa, Japan

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Publications (121)243.02 Total impact

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    ABSTRACT: The aim of the present study was to estimate the benchmark doses (BMD) for renal effects for health risk assessment of residents living in Cd-polluted and non-polluted areas in a Thai population.
    BMC Public Health 07/2014; 14(1):702. · 2.08 Impact Factor
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    ABSTRACT: The aim of this study was to establish the cause-effect relationship between renal tubular dysfunction and mortality. A 19-year cohort study was conducted in 900 men and 1313 women in 1993 or 1994 who lived in two cadmium non-polluted areas in Japan. Hazard ratio (HR) and 95% confidence interval (95% CI) of urinary β2-microglobulin (β2-MG) and N-acetyl-β-glucosaminidase (NAG) for mortality were calculated using a proportional hazard regression. Forward stepwise model selection was applied to the potential covariates such as age, body mass index, mean arterial pressure, various lifestyle factors and present illness. Simultaneously, the dose-effect relationship between renal tubular markers and urinary cadmium at baseline was evaluated using multiple regression analyses. In men, HR was significant for β2-MG (HR corresponding to an increase of 100 μg/g cre: 1.02) and NAG (HR corresponding to an increase of 1 IU/g cre: 1.05). In women, a significant HR was observed for β2-MG (HR corresponding to an increase of 100 μg/g cre: 1.01) and NAG (HR corresponding to an increase of 1 IU/g cre: 1.02). Dose-effect relationships were significant for urinary cadmium and all renal tubular markers in men and women. The present study indicated that renal tubular dysfunction was significantly related to mortality in the general population of cadmium non-polluted areas in Japan.Journal of Exposure Science and Environmental Epidemiology advance online publication, 18 June 2014; doi:10.1038/jes.2014.44.
    Journal of Exposure Science and Environmental Epidemiology 06/2014; · 3.19 Impact Factor
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    ABSTRACT: Abstract A recent study found an inverse correlation between serum TCDD levels and serum testosterone in the US veterans, while there is little known on the dioxin and steroid hormones about Vietnamese men. We collected blood samples from 48 men who had resided in a hotspot when exposure happened and 38 men in a non-sprayed area. Some steroid hormones levels showed significant differences between two areas. There were no correlations between steroid hormones and dioxin TEQ, after ajusting for age and other factors. Our findings indicate that steroid hormones of Vietnamese men did not correlate with dioxin TEQ in two areas.
    Biomarkers 03/2014; · 1.88 Impact Factor
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    ABSTRACT: Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)-the toxic equivalents (TEQ) levels17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).Molecular Psychiatry advance online publication, 18 March 2014; doi:10.1038/mp.2014.18.
    Molecular Psychiatry 03/2014; · 15.15 Impact Factor
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    ABSTRACT: We aimed to investigate the mortality and causes of deaths of inhabitants with renal dysfunction induced by cadmium (Cd) exposure caused by heavy environmental contamination. We conducted a 26-year follow-up survey targeting 7529 inhabitants of the Cd-polluted Jinzu River basin and 2149 controls from non-polluted areas who participated in urinary examinations for proteinuria and glucosuria conducted in 1979 to 1984. When the residents were divided into 4 groups, no finding group, glucosuria group, proteinuria group, glucoproteinuria group, mortality risk ratios for all and specific causes of these groups in the polluted area were compared with that of controls without glucosuria and/or proteinuria after adjustments for age at baseline, smoking status, and history of hypertension using Cox's proportional hazard model. The mortality risk ratios for all causes of proteinuria and glucoproteinuria in men and glucosuria, proteinuria, and glucoproteinuria in women of the polluted areas significantly increased compared with those of the controls with no urinary findings. Respiratory, renal, and cardiovascular diseases and diabetes in men, and all diseases except cerebrovascular diseases in women contributed toward an increased mortality of exposed glucoproteinuria groups, which involved chronic Cd toxicosis with renal tubular dysfunction. In women, the mortality risks for cancer of the colon and rectum, uterus and kidney and urinary tract were significantly higher in the exposed proteinuria and glucoproteinuria groups, suggesting associations between renal damage and cancer risk. In exposed women, the no finding group and glucoproteinuria group also showed increased mortality from ischemic heart diseases, indicating that all exposed women may be at risk for ischemic heart diseases. Although the control glucosuria and/or proteinuria group also showed high mortality for diabetes and renal diseases, the increased risk ratio for renal disease mortality was much higher in exposed subjects with urinary findings, particularly in women. These findings indicate that inhabitants with renal effects caused by Cd exposure had a poor life prognosis over long-term observation in both genders. Particularly in women, renal tubular dysfunction indicated by glucoproteinuria may increase mortality from cancer, ischemic heart diseases, and renal diseases.
    Environmental Health 03/2014; 13(1):18. · 2.71 Impact Factor
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    ABSTRACT: Recent studies have found elevated dioxin levels inside some US military former air bases in Vietnam, known as hotspots. Many studies of Agent Orange have been done in the U.S. veterans; however, there is little known about Vietnamese men. In 2010, we collected blood samples from 97 men in a hotspot and 85 men in an unsprayed area in Northern Vietnam. Serum concentrations of not only TCDD but also other dioxins (PCDDs), furans (PCDFs), and non-ortho polychlorinated biphenyls (PCBs) were significantly higher in the hotspot than in the unsprayed area. In the hotspot, three sub-areas were demarcated, based on their proximity to the air base. The total toxic equivalents (TEQ) of PCDDs/PCDFs+PCBs was 41.7 pg/g lipid in the area closest to the air base, while it was around 29 pg/g lipid in the other two sub-areas. In the unsprayed area, the dioxin levels were no different between men who went to the South during the Vietnam War and those who remained in the North, with TEQs PCDDs/PCDFs+PCBs of around 13.6 pg/g lipid. Our findings suggested that people living close to the former US air bases might have been exposed to both Agent Orange and other sources of dioxin-like compounds.
    Environmental Science & Technology 02/2014; · 5.48 Impact Factor
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    ABSTRACT: The aim of this study was to estimate the reference level of cadmium in rice as the benchmark doses (BMD) and their 95% lower confidence limits (BMDL) for various renal effects by applying an updated hybrid approach. The participants were 1120 men and 1274 women aged 50 years or older who lived in the environmentally exposed Kakehashi river basin for at least 30 years. As indicators of renal dysfunction, glucose, protein, aminonitrogen, metallothionein and β2 -microgrobulin in urine were measured. Cadmium concentration was determined for rice samples stored in warehouses of the farmers in all of the polluted hamlets. The BMD and BMDL that corresponded to an additional risk of 5% were calculated with background risk at a zero exposure set at 5%. The obtained BMDLs were 0.39 (aminonitrogen), 0.26 (metallothionein), 0.25 (β2 -microgrobulin) mg kg(-1) in men and 0.44 (glucose), 0.32 (protein), 0.33 (aminonitrogen), 0.28 (metallothionein) and 0.24 (β2 -microgrobulin) mg kg(-1) in women. The lowest BMDL was 0.25 and 0.24 mg kg(-1) (β2 -microgrobulin) in men and women respectively. These values were lower than the maximum level (0.4 mg kg(-1) ) determined by the Codex Alimentarius Commission, indicating that these BMDLs may contribute to further discussion on the health risk assessment of cadmium exposure. Copyright © 2014 John Wiley & Sons, Ltd.
    Journal of Applied Toxicology 01/2014; · 2.60 Impact Factor
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    ABSTRACT: First, the urinary metabolic profiling by gas chromatography-mass spectrometry (GC-MS), was performed to compare ten cadmium (Cd) toxicosis cases from a Cd-polluted area in Mae Sot (Thailand) with gender-matched healthy controls. Orthogonal partial list square-discrimination analysis was used to identify new biomarker candidates in highly Cd exposed toxicosis cases with remarkable renal tubular dysfunction. The results of the first step of this study showed that urinary citrate was a negative marker and myo-inositol was a positive marker for Cd toxicosis in Thailand. In the second step, we measured urinary citrate in the residents (168 Cd-exposed subjects and 100 controls) and found significantly lower levels of urinary citrate and higher ratios of calcium/citrate and magnesium/citrate, which are risk factors for nephrolithiasis, in highly Cd-exposed residents. Additionally, this inverse association of urinary citrate with urinary Cd was observed after adjustment for age, smoking and renal tubular dysfunction, suggesting a direct effect of Cd on citrate metabolism. These results indicate that urinary citrate is a useful biomarker for the adverse health effects of Cd exposure in a Thai population with a high prevalence of nephrolithiasis.
    International Journal of Environmental Research and Public Health 01/2014; 11(4):3661-77. · 2.00 Impact Factor
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    ABSTRACT: The aim of this study was to clarify the relationship between dioxin concentrations in breast milk and the sister chromatid exchange (SCE) frequency in women from herbicide-sprayed and non sprayed areas. Blood samples were taken from 21 women with high TCDD (tetrachlorodibenzo-p-dioxin) levels from sprayed areas, 23 women with moderate TCDD levels from sprayed areas, and 19 women from non sprayed areas to determine their SCE frequency. The SCE frequencies for the high and moderate TCDD groups from the sprayed area and for the non sprayed area group were 2.40, 2.19, and 1.48 per cell, respectively. Multiple regression analysis showed that the standardized β values for 1,2,3,6,7,8-hexaCDD (β = 0.60), 1,2,3,4,6,7,8-heptaCDD (β = 0.64), and octaCDD (β = 0.65) were higher than those for TCDD (β = 0.34) and 1,2,3,7,8-pentaCDD (β = 0.42). The adjusted R2 value for polyCDDs (R2 = 0.38) was higher than that for polyCDD toxic equivalents (TEQ (toxic equivalents); R2 = 0.23). This study therefore shows that levels of hexa-, hepta-, and octaCDD, which were previously regarded as being less toxic than TCDD, are closely related to SCE frequency and that the level of dioxin (pg/g lipid) is potentially more useful as an indicator than TEQ value for explaining SCE frequency.
    International Journal of Molecular Sciences 01/2014; 15(5):7485-7499. · 2.46 Impact Factor
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    ABSTRACT: Purpose The aim of the present study was to evaluate the dose-effect relationship between urinary cadmium (U-Cd as an index of internal Cd exposure) and mortality in a cohort of the Japanese general population. Methods A 19-year cohort study was conducted in 897 men and 1307 women who lived in two non-polluted areas in Japan. The subjects were categorized into four quartiles (lowest, lower, higher, highest) based on creatinine adjusted U-Cd (μg/g cre). Hazard ratio (HR) and 95% confidence interval (95%CI) of the quartiles of U-Cd for mortality was calculated using a proportional hazards regression. Forward stepwise model selection was applied to the potential covariates such as age, body mass index, mean arterial pressure, various lifestyle factors and present illness. Results The mortality rates per 1000 person years were 27.8 and 12.5 in men and women, respectively. In men, the fourth quartile of U-Cd (≥ 2.919 μg/g cre) showed a significant, positive HR (1.50, 95%CI: 1.11-2.02) for mortality compared to the first quartile (< 1.014). In women, the fourth quartile of U-Cd (≥ 3.943 μg/g cre) also showed a significant HR (1.50, 95%CI: 1.08-2.09) for mortality compared to the first quartile (< 1.140). Conclusion The present study clarified that U-Cd was significantly associated with increased mortality, indicating the worsened life prognosis of the general population in Cd non-polluted areas in Japan. These results highlight the importance of further discussion of the health risk assessment of Cd exposure in the general population.
    International Journal of Hygiene and Environmental Health. 01/2014;
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    ABSTRACT: This study looked to identify determinants of exposure to dioxin in breast milk from breast-feeding women in a hot spot of dioxin exposure in Vietnam. Breast milk was collected from 140 mothers 1 month after delivery. The risk factors investigated included length of residency, drinking of well water and the frequency of animal food consumption. Cluster analysis was performed to identify dietary patterns of fish and meat portions, fish variety and egg variety. Residency, age and parity were clearly associated with increased dioxin levels. Drinking well water and the consumption of marine crab and shrimps were related to higher levels of furans in breast milk. The consumption of quail eggs also appeared to be associated with increased levels of some dioxin isomers in this area. Some mothers who ate no or less meat than fish and mothers who consumed more freshwater fish than marine fish had lower levels of dioxins in their breast milk. However, the type of water and the eating habits of mothers contributed only partly to the increased dioxin levels in their breast milk; the length of residency was the most important risk factor associated with increased dioxin body burdens of mothers.Journal of Exposure Science and Environmental Epidemiology advance online publication, 23 October 2013; doi:10.1038/jes.2013.73.
    Journal of Exposure Science and Environmental Epidemiology 10/2013; · 3.19 Impact Factor
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    ABSTRACT: Dioxin (PCDDs+PCDFs), is one of the most toxic chemical substances known. Although it is suspected to cause endocrine disruption, very few epidemiological studies into its effects on human steroid hormones have been performed. The aim of this study is to elucidate the association of dioxin exposure with steroid hormone levels in the saliva and serum of lactating Vietnamese women. Two areas, namely Phu Cat (hot-spot) and Kim Bang (non-exposed area), were selected for study. The study subjects consisted of 51 and 58 lactating women, respectively. Saliva, blood and breast milk samples were collected from subjects in both areas. Cortisol, cortisone, dehydroepiandrosterone, androstenedione, estrone and estradiol levels in serum and saliva were determined by liquid-chromatography/tandem mass spectrometry (LC-MS/MS); dioxin levels in breast milk were measured by gas-chromatography-mass spectrometry (GC-MS). The dioxin concentration in breast milk from women in the hot-spot area was 3-4 times higher than in women from the non-exposed area. Good correlations were found between the levels of six steroid hormones in saliva and those in serum, respectively. Salivary and serum cortisol and cortisone levels in women from the hot spot were significantly higher than in those from the non-exposed area (P<0.001) and those in all subjects were positively associated with dioxin levels in Vietnamese women (P<0.01). These results suggest that dioxin influences steroidogenesis in humans. Saliva sample can be used for hormone analysis and are therefore excellent specimens in epidemiological studies.
    European Journal of Endocrinology 10/2013; · 3.14 Impact Factor
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    ABSTRACT: Previous studies have reported that maternal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces socioemotional and cognitive disturbances in rat offspring. In the present study, the effects of maternal TCDD exposure on putative inhibitory interneurons were investigated in the medial prefrontal cortex (mPFC), basolateral amygdala (BLA), hippocampus (HP), and superior colliculus (SC) in rat offspring. Dams were given TCDD (1.0μg/kg) on gestational day 15. When offspring rats reached adulthood (14 weeks old), parvalbumin (PV)- and calbindin (Calb)-immunoreactive neurons were immunohistochemically investigated. The histological investigations indicated that the mean area of the mPFC had increased, whereas the mean area of the SC decreased in the exposed male rats. In the exposed female rats, the mean SC area increased. Furthermore, the number and area of PV-immunoreactive neurons increased in the mPFC of the female exposed rats. In contrast, the number of PV-immunoreactive neurons in the BLA, HP, and SC decreased in the male and female exposed rats. The number of Calb-immunoreactive neurons decreased in the HP of the male and female exposed rats and the SC of the female exposed rats. Because PV- and Calb-immunoreactive neurons, which are putatively GABAergic, have been implicated in various higher brain functions, the effects of TCDD on socioemotional and cognitive functions might be mediated partly through these alterations in PV- and Calb-immunoreactive neurons in these areas.
    Toxicology 09/2013; · 4.02 Impact Factor
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    ABSTRACT: OBJECTIVES: The aim of this study was to explore the impact of Agent Orange exposure for prostate cancer with a comparison of the prostate specific antigen (PSA) levels between a hotspot and a non-sprayed area. METHODS: The study was conducted in Phu Cat district (hotspot) and Kim Bang district (non-sprayed), with a total of 101 men in the hotspot and 97 men in the non-sprayed area older than 50 years of age. About 5 mL of whole blood and a health status questionnaire were collected from each subject in August 2009-2011. RESULTS: The mean age of the subjects in the hotspot (68.0 years old) was significantly higher than that of those in the non-sprayed area (65.0 years old). No significant difference was found between the hotspot area (0.93 ng/mL) and the non-sprayed area (0.95 ng/mL) in terms of PSA levels. Likewise, this was not statistically significant after adjusting for age. The prevalence of high PSA levels (>3 ng/mL) did not differ significantly between the hotspot (14 men; 13.9 %) and non-sprayed area (9 men; 9.3 %). No significant difference was found between the hotspot area and the non-sprayed area in terms of occupation (farmer and others). In control subjects, no significant difference was found between the PSA levels in subjects exposed to Agent Orange and non-exposed subjects. Likewise, no significant difference was found between the PSA levels of combatants and civilians. CONCLUSION: The PSA levels were not significantly different between the hotspot and the non-sprayed area.
    Environmental Health and Preventive Medicine 03/2013;
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    ABSTRACT: BACKGROUND: Previous U.S. population modeling studies have reported that urinary cadmium (Cd) excretion patterns differ with age, sex, and dietary exposure, and associations between Cd exposures and health outcomes also have differed by age and sex. Therefore, it is important to test models used to estimate Cd exposures across an expanded Cd exposure range. OBJECTIVES: Estimate relative Cd exposures from both diet and smoking in low- and high-exposure scenarios to provide data for improving risk assessment calculations. METHODS: We used a Cd toxicokinetic-based model to estimate Cd exposures based on urinary Cd levels measured for 399 persons in a low-exposure (Bangkok) area and 6747 persons in a high-exposure (Mae Sot) area in Thailand. RESULTS: In Bangkok, we estimated dietary Cd exposures of 50-56 µg/day for males and 21-27 µg/day for females 20 to 59 years of age who never smoked. In Mae Sot, we estimated dietary Cd exposures of 188-224 µg/day for males and 99-113 µg/day for females. In Bangkok, we estimated Cd exposures from smoking of 5.5-20.4 µg/day for male smokers 20-59 years of age. In Mae Sot, we estimated Cd exposures from smoking of 9.8-26µg/day for male heavy smokers and 26µg/day for female heavy smokers. CONCLUSION: This study provides estimates of Cd exposures from diet and smoking in low- and high-exposure scenarios. Our findings suggest a relatively small safety margin between the established tolerable Cd reference exposure of 62μg/day and exposure levels previously associated with evidence of kidney and bone effects in Mae Sot residents, where dietary Cd exposures among women were only 1.6- to 2.1-times the reference value.
    Environmental Health Perspectives 02/2013; · 7.26 Impact Factor
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    ABSTRACT: OBJECTIVES: Dioxin levels in the breast milk of mothers residing near hot spots of dioxin contamination areas in South Vietnam remain much higher than in unsprayed areas, suggesting that fetuses and breast-fed infants may be exposed to high levels of dioxins. The present study investigated the association of infant neurodevelopment in early infancy and dioxin exposure during the perinatal period. METHODS: The study involved 216 mother-infant pairs living near the Da Nang airbase, a dioxin contaminated area in Vietnam. Mothers and infants were followed from birth until infants were 4 months old. Dioxin levels in breast milk were measured to estimate the perinatal dioxin exposure, including the infant daily dioxin intake (DDI) via breastfeeding. Infant neurodevelopmental parameters, including cognitive, language and motor domains were assessed at approximately 4 months using the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III). RESULTS: The level of 2,3,7,8-tetrachlorodibenzo-p-dioxin and polychlorinated dibenzo-p-dioxins/furans-toxic equivalents in breast milk and the infant DDI showed significant inverse correlations with neurodevelopmental scores. When the subjects were divided into four groups according to dioxin levels in breast milk, the moderate and high DDI groups had significantly lower cognitive, composite motor and fine motor scores, and the high polychlorinated dibenzo-p-dioxins/furans-toxic equivalents group had significantly lower fine motor score than the low exposure group. For all domains, neurodevelopmental scores were decreased with increase in the level of 2,3,7,8-tetrachlorodibenzo-p-dioxin. CONCLUSION: The present study demonstrates a considerable impact of perinatal dioxin exposure on neurodevelopment in 4-month-old infants living in contaminated areas in Vietnam.
    Occupational and environmental medicine 02/2013; · 3.64 Impact Factor
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    ABSTRACT: Effects of dioxins on cognitive functions were reported in previous studies conducted in humans and animals. In the present study, we investigated the influence of dioxin exposure during pregnancy on social interaction and on the activity of offspring, which are related to neurodevelopmental disturbances. In addition, we analyzed neurochemical alterations of the limbic system of rat brains to suggest one mechanism of dioxin effects on brain function. We believe that this manuscript is suitable for publication in "Environmental Health Insights" because it provides an interesting topic for a wide global audience. To clarify the relationships between maternal dioxin exposure and socioemotional functions of rat offspring, dams were given TCDD (1.0 μg/kg) on gestational day 15. Social interactions and forced swimming time were compared between TCDD-exposed and control offspring in each gender. Frequency and duration of locomotion were higher, and durations per one behavior of proximity and social contact were significantly lower in the exposed males, while only the duration of proximity was lower in the exposed females. Forced swimming time on the first day was significantly longer in the exposed males. In the limbic system of the rat brain, the levels and/or activity of CaMKIIα were decreased in males and were increased in females in the exposed offspring. These results suggest that prenatal TCDD exposure induces hyperactivity and socioemotional deficits, particularly in the male offspring due to alterations in CaMKIIα activity in the limbic system of the brain.
    Environmental Health Insights 01/2013; 7:1-14.
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    ABSTRACT: Cadmium (Cd) has been found as an environmental pollutant in Mae Sot district, Tak province, Thailand. Prolong exposure to high levels of Cd of the resident increases high risk of Cd toxicity especially to kidney which is the primary target of Cd. In order to investigate the early effect of Cd induced renal dysfunction, a kidney injury molecule-1 (KIM-1), a novel biomarker of renal tubular dysfunction, was measured using an enzyme linked immunosorbent assay (ELISA). The method was validated and used to quantify the KIM-1 concentrations in the urine of 700 subjects (260 men, 440 women) who lived in the Cd contaminated area. The KIM-1 concentrations were compared to the concentrations of two conventional renal tubular dysfunction biomarkers, N-acetyl-β-D-glucosaminidase (NAG) and β2-microglobulin (β2-MG). Urinary KIM-1 was correlated with urinary and blood Cd as well as NAG. After adjustment of age and smoking, urinary KIM-1 was correlated with blood Cd more than urinary NAG did. Clear dose response relationships of urinary KIM-1 with urinary Cd were shown in both men and women. These results indicate that the urinary KIM-1 might be more sensitive biomarker than urinary NAG and β2-MG for an early detection of renal tubular dysfunction. It is useful as a tool to detect renal effect of toxicity due to chronic Cd exposure at high level.
    SpringerPlus 01/2013; 2:533.
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    ABSTRACT: OBJECTIVE: Nearly 40 years after Agent Orange was last sprayed, we conducted a cross-sectional study to evaluate the impact of dioxin exposure on salivary hormones in Vietnamese primiparae. Our previous studies found higher levels of salivary cortisol and cortisone in one of the most highly dioxin-contaminated areas, known as a "hot-spot", than in a non-exposed area. As a result, we suggested that further research with a larger number of participants would be needed to confirm whether dioxin affects steroid hormone levels in Vietnamese primiparae. METHODS: The concentration of steroid hormones in saliva was determined by liquid chromatography (electrospray ionization tandem mass spectrometry), whereas the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in breast milk were determined by gas chromatography-high resolution mass spectrometry, for a sample of the population from a "hot-spot" (n = 16) and a non-exposed area (n = 10). All subjects were aged between 20 and 30 years and had children aged between 4 and 16 weeks. RESULTS: The mean toxic equivalence of PCDDs, PCDFs and PCDDs + PCDFs in breast milk in the hot-spot area was found to be significantly higher than in the non-exposed area (p < 0.001). Likewise, salivary cortisol, cortisone and dehydroepiandrosterone (DHEA) levels were significantly higher in the hotspot area than in the non-exposed area (p < 0.05). As a result, herein we report, for the first time, that salivary DHEA levels in primiparae are higher in a hot-spot than in a non-exposed area, and that this may be the result of dioxin exposure. CONCLUSIONS: Our findings highlight the long-term effects of Agent Orange/dioxin on steroid hormones in Vietnamese primiparae in the post-war period.
    Environmental Health and Preventive Medicine 11/2012;
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    ABSTRACT: Japan has a relatively high prevalence of smoking in men. Despite the importance of behavioral patterns on successful smoking cessation, only limited information is available in Japan. The present study collected data from former smokers in a rural community in Japan in order to identify health status at the time of cessation, predominant motivating factors, and the role of smoking cessation aids in individuals who successfully stopped smoking. This cross-sectional study collected data using a self-reported questionnaire from 149 randomly-selected former smokers (119 men and 30 women, aged 20-79 years) who were residents of Nanao, Ishikawa Prefecture, Japan. Of the male participants, 14.3% quit due to serious personal health problems, including cardiovascular disease, cancer, or respiratory tract disease, while 20.8% of former smokers experienced mild personal health problems or were pregnant at the time of cessation. An approximately equal number stopped smoking due to fear of illness in the absence of immediate health concerns. Compared to personal health motivations, a smaller number of male smokers quit due to anti-smoking social pressure or expense. We also observed a marked increase in former smokers who quit for these reasons in recent years. Smoking lost its appeal in 19.3% of male and 10.0% of female smokers. Approximately, 95% of quitters did not utilize health professional counseling or pharmacological therapy. Personal health concerns in former smokers in Nanao, Japan were the predominant motivation for quitting smoking, with the vast majority of former smokers achieving successful smoking cessation by themselves.
    International journal of preventive medicine 07/2012; 3(7):459-65.

Publication Stats

1k Citations
243.02 Total Impact Points


  • 1993–2014
    • Kanazawa Medical University
      • • Department of Epidemiology and Public Health
      • • School of Nursing
      Kanazawa, Ishikawa, Japan
  • 2013
    • University of Toyama
      • Department of System Emotional Science (Physiology 1)
      Тояма, Toyama, Japan
  • 2007–2013
    • Chiang Mai University
      • • Faculty of Medicine
      • • Faculty of Associated Medical Sciences
      • • Department of Forensic Medicine
      Amphoe Muang Chiang Mai, Chiang Mai, Thailand
  • 2004–2013
    • Kanazawa University
      • • Graduate School of Medical Sciences
      • • School of Health Sciences
      Kanazawa, Ishikawa, Japan
  • 2002–2009
    • Chiba University
      • Graduate School of Medicine
      Chiba-shi, Chiba-ken, Japan
    • Kanazawa Gakuin University
      Kanazawa, Ishikawa, Japan
  • 2004–2006
    • University of Queensland 
      • National Research Centre for Environmental Toxicology
      Brisbane, Queensland, Australia