Periosteum-derived podoplanin-expressing stromal cells regulate nascent vascularization during epiphyseal marrow development.

Bone marrow development and endochondral bone formation occur simultaneously. During endochondral ossification, periosteal vasculatures and stromal progenitors invade the primary avascular cartilaginous anlage, which induces primitive marrow development. We previously determined that bone marrow podoplanin (PDPN)-expressing stromal cells exist in the perivascular microenvironment and promote megakaryopoiesis and erythropoiesis. In this study, we aimed to examine the involvement of PDPN-expressing stromal cells in postnatal bone marrow generation. Using histological analysis, we observed that periosteum-derived PDPN-expressing stromal cells infiltrated the cartilaginous anlage of the postnatal epiphysis and populated on the primitive vasculature of secondary ossification center. Furthermore, immunophenotyping and cellular characteristic analyses indicated that the PDPN-expressing stromal cells constituted a subpopulation of the skeletal stem cell lineage. In vitro xenovascular model cocultured with human umbilical vein endothelial cells and PDPN-expressing skeletal stem cell progenies showed that PDPN-expressing stromal cells maintained vascular integrity via the release of angiogenic factors and vascular basement membrane-related extracellular matrices. We show that in this process, Notch signal activation committed the PDPN-expressing stromal cells into a dominant state with basement membrane-related extracellular matrices, especially type IV collagens. Our findings suggest that the PDPN-expressing stromal cells regulate the integrity of the primitive vasculatures in the epiphyseal nascent marrow. To the best of our knowledge, this is the first study to comprehensively examine how PDPN-expressing stromal cells contribute to marrow development and homeostasis.

Association of Redox State of Human Serum Albumin with Severity in Patients with Heart Failure.

Oxidative stress plays a crucial role in the progression of heart failure (HF). We surveyed the fraction of human mercaptalbumin [f (HMA) ], an indicator of the redox state of human serum albumin (HSA), in patients with HF and examined whether f (HMA) is associated with the severity of HF.We enrolled consecutive elderly patients hospitalized for acute HF or exacerbation of HF. The redox state of HSA was measured by the high-performance liquid chromatography with postcolumn bromocresol green method using serum samples collected close to discharge. First, the distribution of f (HMA) in HF was compared to that in community-dwelling elderly individuals (n = 125; median age, 80 years) as a control group analyzed in a previous study. Overall, 133 patients (median age, 81 years; 75 men) were included. Patients with HF showed a lower level of f (HMA) than those of the control group (55.0% [IQR 47.7-61.3] versus 66.3% [IQR 62.8-70.0], P < 0.001]. Multiple regression analysis showed a negative correlation between f (HMA) and log-transformed B-type natriuretic peptide (standardized beta = -0.19).Patients with HF showed lower f (HMA) than those in the control group. Additionally, f (HMA) was related to HF independently with log-transformed B-type natriuretic peptide in the multivariate regression analysis, suggesting that f (HMA) is a biomarker that reflects the redox state in HF patients.

Simultaneous quantification of pyrethroid metabolites in urine of non-toilet-trained children in Japan.

BACKGROUND: Pyrethroid (PYR) insecticides are widely used for controlling various pests. There are two types that differ in terms of usage: agricultural-purpose PYR (agriculture-PYR) and hygiene purpose PYR (hygiene-PYRs). Few studies exist on the exposure to these chemicals in small children. In this study, we conducted biomonitoring of urinary pyrethroid metabolites in 1.5-year-old children throughout the year. METHODS: Study subjects were 1075 children participating in an Aichi regional sub-cohort of the Japan Environment and Children's Study as of 18-month health check-up. The concentrations of four specific hygiene-PYR metabolites including 2,3,5,6-tetrafluoro-1,4-benzenedimethanol (HOCH2-FB-Al), and five common metabolites of hygiene- and agriculture-PYRs including 3-phenoxybenzoic acid (3PBA) and cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (DCCA), were measured in urine samples extracted from soiled diapers using a triple quadrupole gas chromatograph-mass spectrometer. RESULTS: The highest detection frequencies were for 3PBA, followed by DCCA, 1R-trans-chrysanthemum dicarboxylic acid, and HOCH2-FB-Al. Among the six metabolites, urinary concentrations were seasonally varied. However, this variation was not observed in the most studied PYR metabolite, 3PBA. Spearman's correlation analysis demonstrated a significant positive correlation between FB-Al and DCCA (r = 0.56) and HOCH2-FB-Al and 4-methoxymethyl-2,3,5,6-tetrafluorobenzyl alcohol (r = 0.60). CONCLUSIONS: This biomonitoring survey found widespread and seasonally specific exposure to multiple hygiene- and agriculture-PYRs in 1.5-year-old Japanese children.

[Survey of Arsenic/Heavy Metals and Pesticide Residues in Edible Insects for Human Consumption or Supplied in Japan].

Arsenic (As) and heavy metals (Cd, Hg, Pb, and Cu) and pesticide residues in 14 edible insects were investigated. The maximum levels of elements were 6.15 for As, 0.82 for Cd, 0.50 for Hg, 0.67 for Pb, and 297.7 ppm for Cu. Fenobucarb (or BPMC) has been quantified through GC- and LC-MS/MS analysis at a concentration of approximately 3 ppm. Further studies of the contaminants may help ensure the safety of edible insect consumption.

Meta-Analysis of Gut Dysbiosis in Parkinson's Disease.

BACKGROUND: PD may begin with the intestinal accumulation of α-synuclein fibrils, which can be causally associated with gut dysbiosis. The variability of gut microbiota across countries prevented us from identifying shared gut dysbiosis in PD. OBJECTIVES: To identify gut dysbiosis in PD across countries. METHODS: We performed 16S ribosomal RNA gene sequencing analysis of gut microbiota in 223 patients with PD and 137 controls, and meta-analyzed gut dysbiosis by combining our dataset with four previously reported data sets from the United States, Finland, Russia, and Germany. We excluded uncommon taxa from our analyses. For pathway analysis, we developed the Kyoto Encyclopedia of Genes and Genomes orthology set enrichment analysis method. RESULTS: After adjusting for confounding factors (body mass index, constipation, sex, age, and catechol-O-methyl transferase inhibitor), genera Akkermansia and Catabacter, as well as families Akkermansiaceae, were increased, whereas genera Roseburia, Faecalibacterium, and Lachnospiraceae ND3007 group were decreased in PD. Catechol-O-methyl transferase inhibitor intake markedly increased family Lactobacillaceae. Inspection of these bacteria in 12 datasets that were not included in the meta-analysis revealed that increased genus Akkermansia and decreased genera Roseburia and Faecalibacterium were frequently observed across countries. Kyoto Encyclopedia of Genes and Genomes orthology set enrichment analysis revealed changes in short-chain fatty acid metabolisms in our dataset. CONCLUSIONS: We report that intestinal mucin layer-degrading Akkermansia is increased and that short-chain fatty acid-producing Roseburia and Faecalibacterium are decreased in PD across countries. © 2020 International Parkinson and Movement Disorder Society.

Freeze-drying enables homogeneous and stable sample preparation for determination of fecal short-chain fatty acids.

BACKGROUND: The analysis methods for fecal short-chain fatty acids (SCFAs) have evolved considerably. Recently, the role of SCFAs in gastrointestinal physiology and their association with intestinal microbiota and disease were reported. However, the intra-fecal variability and storage stability of SCFAs have not been extensively investigated. The aim of this study was to understand the limitations of the measurement of SCFAs in crude feces and develop a useful pre-examination procedure using the freeze-drying technique. METHODS: SCFAs in crude feces, obtained from healthy volunteers, and freeze-dried feces were determined by derivatization with isobutyl chloroformate, followed by liquid-liquid extraction with hexane, and separation and analysis using gas chromatography-mass spectrometry. RESULTS: Among the SCFAS, the maximum intra-fecal variability was observed for iso-butyrate (coefficient of variation of 37.7%), but the freeze-drying procedure reduced this variability (coefficient of variation of 7.9%). Similar improvements were also observed for other SCFAs. Furthermore, significant decreases in the SCFA amounts were observed with storage at 4 °C for 24 h. CONCLUSIONS: The freeze-drying procedure affords fecal SCFA stability, even with storage at room temperature for 3 d. The freeze-drying procedure allows reliable SCFA measurements without labour-intensive processes. Therefore, the freeze-drying procedure can be applied in basic, clinical, and epidemiological studies.

Optimization and validation of a highly sensitive method for determining glyphosate in human urine by solid-phase extraction and liquid chromatography with tandem mass spectrometry: a methodological study.

BACKGROUND: Glyphosate and its salt formulations are nonselective herbicides that have been extensively used worldwide, both for residential and agricultural purposes. The possible carcinogenicity and teratogenicity of glyphosate remain to be elucidated. We developed a sensitive and high-throughput analytical method for urinary glyphosate using liquid chromatography-tandem mass spectrometry with the aim of contributing to glyphosate exposure assessment in epidemiological studies. METHODS: After urine dilution (creatinine matching dilution to 0.05 g creatinine/L), glyphosate was extracted using two types of solid phase extraction columns (SCX and NH2) with automated sample preparation instruments. The eluate was dried and dissolved in the mobile phase, followed by liquid chromatography-tandem mass spectrometry analysis. The optimized method was applied to urine samples obtained from 54 Japanese adults and children. RESULTS: The results from the validation study demonstrated good recoveries (91.0-99.6%), within- and between-run precisions (< 15%), low detection limits (0.1 µg/L), and lower limit of quantification (0.3 µg/L). The detection frequency and median concentration of the urinary glyphosate in Japanese subjects were 59% and 0.25 µg/L (0.34 µg/g creatinine). CONCLUSIONS: Our reliable determination method was successful in measuring urinary glyphosate concentration. Moreover, this is the first biomonitoring report of urinary glyphosate levels in the Japanese general population.

Human serum albumin redox state is associated with decreased renal function in a community-dwelling population.

The redox state of human serum albumin (HSA) has attracted interest as a possible biomarker for oxidative stress (OS) in humans. Although previous studies on this topic have taken only clinical settings into consideration, evidence of its efficacy in nonclinical settings remains to be established. The present study aimed to examine and validate the relationship between HSA redox state and renal function in a rural Japanese population. We analyzed two independent data sets from health checkup programs conducted in 2013 and 2016: one for discovery ( n = 267) and the other for replication ( n = 367). The fraction of human mercaptalbumin (HMA) to total HSA [f(HMA)] was determined using our revised method of high-performance liquid chromatography with post-column bromocresol green. The estimated glomerular filtration rate (eGFR) was calculated based on each individual's serum creatinine value, sex, and age. Adjustment for potential confounders revealed positive associations of fraction of human mercaptalbumin [f(HMA)] with eGFR in the discovery and replication analyses ( P < 0.001 and P = 0.03, respectively). Multivariate logistic regression analyses demonstrated significant inverse associations between renal dysfunction (defined as eGFR < 60 ml·min-1·1.73 m-2) and f(HMA) by a factor of 0.50 and 0.65 (confidence intervals of 0.26-0.91 and 0.37-1.00), respectively, with a unit of 10% f(HMA). Our results indicate that HSA redox state is consistently associated with renal dysfunction in both clinical and nonclinical settings.

Association between exposure to household smoking and dental caries in preschool children: a cross-sectional study.

BACKGROUND: We aimed to examine the association of exposure to environmental tobacco smoke with dental caries among preschool children. Exposure to environmental tobacco smoke was assessed in terms of urinary cotinine concentrations and pack-years of exposure to smoking by parents and other family members at home. METHODS: This cross-sectional study included 405 preschool children aged 3-6 years from two preschools in Japan in 2006. Information on the smoking habits of family members living with the child was obtained from parent-administered questionnaires. Dental examination was conducted to assess dental caries, that is, decayed and/or filled teeth. Urinary cotinine levels were measured using first-void morning urine samples. RESULTS: Overall, 31.1% of the children had dental caries, and 29.5% had decayed teeth. Exposure to current maternal and paternal smoking was positively associated with the presence of dental caries after controlling for covariates. More than three pack-years of exposure to maternal smoking and more than five pack-years of exposure to smoking by all family members were significantly associated with the presence of dental caries as compared with no exposure (odds ratio [OR] = 5.55, 95% confidence interval [CI] = 2.17-14.22, P for trend < 0.001 and OR = 2.00, 95% CI = 1.12-3.58, P for trend = 0.004, respectively). These exposure variables were similarly associated with the presence of decayed teeth (OR = 2.92, 95% CI = 1.23-6.96, P for trend = 0.01 and OR = 1.75, 95% CI = 0.96-3.20, P for trend = 0.03, respectively). As compared with lowest tertile of the urinary cotinine level, the highest tertile of the urinary cotinine level was significantly associated with the presence of dental caries as well as decayed teeth; the ORs for the highest vs. lowest tertile of urinary cotinine levels were 3.10 (95% CI = 1.71-5.63, P for trend = 0.012) and 2.02 (95% CI = 1.10-3.70, P for trend = 0.10), respectively. CONCLUSIONS: These data suggest that exposure to tobacco smoke may have a dose-dependent influence on the development of caries.

Intra-individual variations of organophosphate pesticide metabolite concentrations in repeatedly collected urine samples from pregnant women in Japan.

BACKGROUND: Low-dose exposure to organophosphate (OP) insecticides during pregnancy may adversely affect neurodevelopment in children. To evaluate the OP exposure levels, single urine sampling is commonly adopted to measure the levels of dialkylphosphates (DAPs), common OP metabolites. However, the inter-day variations of urinary DAP concentrations within subjects are supposed to be large due to the short biological half-lives of the metabolites, and it is thus considered difficult to accurately assess OP exposure during pregnancy with single sampling. This study aimed to assess intra-individual variations of DAP concentrations and the reproducibility of the exposure dose categorization of OPs according to DAP concentration ranges in pregnant women in Japan. METHODS: Urine samples were collected from 62 non-smoking pregnant women (12-22 weeks of gestation) living in Aichi Prefecture, Japan. First morning void (FMV) and spot urine samples taken between lunch and dinner on the same day were collected on five different days during 2 weeks. The concentrations of DAP and creatinine in urine samples were measured using an ultra performance liquid chromatography with tandem mass spectrometry. Creatinine-adjusted and unadjusted concentrations were used for the intraclass correlation coefficient (ICC) calculations and surrogate category analyses. RESULTS: For all DAP metabolites, the creatinine-adjusted single ICCs exceeded 0.4, indicating moderate reliability. Overall, ICCs of spot urine samples taken in the afternoon were better than those taken as FMV. Surrogate category analyses showed that participants were categorized accurately into four exposure dose groups according to the quartile points. CONCLUSION: This study indicated that a single urine sample taken in the afternoon may be useful in assessing OP exposure as long as the exposure is categorized into quartiles when conducting epidemiological studies in early to mid-pregnant women in Japan.

Common variant of BCAS3 is associated with gout risk in Japanese population: the first replication study after gout GWAS in Han Chinese.

BACKGROUND: Gout is a common disease resulting from hyperuricemia which causes acute arthritis. A recent genome-wide association study (GWAS) of gout identified three new loci for gout in Han Chinese: regulatory factor X3 (RFX3), potassium voltage-gated channel subfamily Q member 1 (KCNQ1), and breast carcinoma amplified sequence 3 (BCAS3). The lack of any replication studies of these three loci using other population groups prompted us to perform a replication study with Japanese clinically defined gout cases and controls. METHODS: We genotyped the variants of RFX3 (rs12236871), KCNQ1 (rs179785) and BCAS3 (rs11653176) in 723 Japanese clinically defined gout cases and 913 controls by TaqMan method. rs179785 of KCNQ1 is also evaluated by direct sequencing because of difficulties of its genotyping by TaqMan method. RESULTS: Although the variants of RFX3 and BCAS3 were clearly genotyped by TaqMan method, rs179785 of KCNQ1 was not, because rs179785 (A/G) of KCNQ1 is located at the last nucleotide ("A") of the 12-bp deletion variant (rs200562977) of KCNQ1. Therefore, rs179785 and rs200562977 of KCNQ1 were genotyped by direct sequencing in all samples. Moreover, by direct sequencing with the same primers, we were able to evaluate the genotypes of rs179784 of KCNQ1 which shows strong linkage disequilibrium with rs179785 (D' = 1.0 and r 2 = 0.99). rs11653176, a common variant of BCAS3, showed a significant association with gout (P = 1.66 × 10- 3; odds ratio [OR] = 0.80); the direction of effect was the same as that seen in the previous Han Chinese GWAS. Two variants of KCNQ1 (rs179785 and rs179784) had a nominally significant association (P = 0.043 and 0.044; OR = 0.85 and 0.86, respectively), but did not pass the significance threshold for multiple hypothesis testing using the Bonferroni correction. On the other hand, rs200562977 of KCNQ1 and rs12236871 of RFX3 did not show any significant association with gout. CONCLUSION: BCAS3 is a coactivator of estrogen receptor alpha, and the influence of estrogen to serum uric acid level is well known. Our present replication study, as did the previous gout GWAS, demonstrated the common variant of BCAS3 to be associated with gout susceptibility.

A sensitive and efficient procedure for the high-throughput determination of nine urinary metabolites of pyrethroids by GC-MS/MS and its application in a sample of Japanese children.

Four pyrethroids (PYRs), metofluthrin, profluthrin, tefluthrin, and transfluthrin, which were newly developed and have relatively high vapor activity at ambient temperature, are now playing a key role in safely controlling insects in our daily lives. We developed a sensitive and high-throughput determination method for urinary metabolites derived from the newly developed PYR, e.g., 2,3,5,6-tetrafluoro-1,4-benzenedimethanol (HOCH2-FB-Al), 2,3,5,6-tetrafluorobenzyl alcohol (FB-Al), and other PYR metabolites such as trans-chrysanthemumdicarboxylic acid (trans-CDCA) and 3-phenoxybenzoic acid (3PBA). After high temperature acid hydrolysis of 2 mL urine sample in 24-deep well plate, the PYR metabolites were extracted by semi-automated liquid-liquid extraction with tert-butyl methyl ether. N,O-Bis (trimethylsilyl) trifluoroacetamide containing 1% trimethylchlorosilane or 1,1,1,3,3,3-hexafluoroisopropanol were used for the derivatization of PYR metabolites, and the derivatized metabolites were analyzed separately by GC-MS/MS equipped with dual injector system (DB-5MS and mid- to high-polarity phase Rtx-65 columns). The derivatization and evaporation conditions were mainly optimized for improving sensitivity and reproducibility. The mean within-run day precisions were less than 18.4% (relative standard deviation, %RSD) with low detection limits ranging from 0.01 µg/L for HOCH2-FB-Al to 0.06 µg/L for trans-CDCA. This method was successfully applied to urine samples obtained from 50 3-year-old children with high detection frequencies (e.g., 82% for HOCH2-FB-Al and 84% for FB-Al). This method may be a pivotal tool for developing risk assessment from PYR exposure in the general population.

Oxidized human serum albumin as a possible correlation factor for atherosclerosis in a rural Japanese population: the results of the Yakumo Study.

BACKGROUND: The effect of the redox state of human serum albumin (HSA) on the antioxidant properties of the entire body has been a focus of recent research. The usefulness of HSA redox state as a biomarker for reducing oxidative stress has been investigated in clinical settings; however, evidence for its significance as a health index in non-clinical settings is yet to be established. This study aimed to examine the associations between HSA redox state and the atherosclerotic indices of carotid intima-media thickness (IMT) and plaque formation in a rural Japanese population. METHODS: We conducted a cross-sectional study as part of a health check-up program in the rural area of Hokkaido, Japan, at the end of August 2013. A total of 281 residents (124 men and 157 women) were included in the final analysis. Lifestyle-related data were obtained through a self-reported questionnaire, and ultrasound examinations were performed to measure IMT and determine plaque formation. The high-performance liquid chromatography postcolumn bromocresol green method was used to separate HSA into human nonmercaptalbumin and human mercaptalbumin (HMA). RESULTS: We found a significant negative relationship between the fraction of HMA [f(HMA)] and IMT (standardized ß = - 0.132, p = 0.03). Moreover, f(HMA) was significantly associated with plaque formation (p < 0.01) with an odds ratio of 0.89 (95% confidence interval, 0.81-0.97) for every 10% increment in f(HMA). CONCLUSIONS: We found that the HSA redox state, as determined by f(HMA), was associated with atherosclerotic indices in Japanese subjects. These results suggest that the HSA redox state indicates the risk of developing atherosclerosis.

Association Between Organophosphate Pesticide Exposure and Thyroid Hormones in Pregnant Women.

BACKGROUND: Use of organophosphate pesticides (OPs) is widespread in China. Although animal studies suggested that OP exposure could affect thyroid function, little is explored in human populations. METHODS: We investigated levels of OP exposure in pregnant women and the relationship between OPs and thyroid hormones in Shandong, China. We enrolled 637 pregnant women from April 2011 to December 2013. OP exposure was assessed by a questionnaire administered to the pregnant women in the hospital and by analyses of urinary dialkylphosphate (DAP) metabolites of OPs in pregnant women (n = 413). We measured the concentration of five thyroid hormones in serum samples in pregnant women (n = 325) and analyzed the association between DAP metabolites of OPs and thyroid hormones (n = 325). RESULTS: Median levels of DAP metabolites were 9.81 µg/L for dimethylphosphate (DMP), 0.79 µg/L for dimethylthiophosphate (DMTP), 5.00 µg/L for diethylphosphate (DEP), and 0.78 µg/L for diethylthiophosphate (DETP), which were higher than those reported in developed countries. We found that the total DAP concentration (the sum of DMP, DMTP, DEP, and DETP) in urine was positively associated with free T4 levels (ß = 0.137; 95% confidence interval [CI] = 0.012, 0.263) and negatively associated with thyroid-stimulating hormone levels (ß = -0.145; 95% CI = -0.242, -0.048). CONCLUSIONS: The findings suggest that OP exposure may be associated with changes in thyroid function in pregnant women. Given that urinary OP levels in pregnant women in Shandong were much higher than those reported in developed countries, further studies on the effects of OP exposure on thyroid function in pregnant women in China are warranted.

Exposure characterization of three major insecticide lines in urine of young children in Japan-neonicotinoids, organophosphates, and pyrethroids.

The use of neonicotinoid (NEO) insecticides has increased over the past decade not only in Japan but also worldwide, while organophosphate (OP) and pyrethroid (PYR) insecticides are still conventionally used in agriculture and domestic pest control. However, limited data are currently available on the NEO exposure levels, especially in children, who are particularly vulnerable to environmental toxicants. Thus, the purpose of this study was to characterize the exposure to NEOs, as well as OPs and PYRs, in three-year-old Japanese children by assessing the range, distribution, and seasonal differences of the urinary concentrations of seven NEOs (acetamiprid, clothianidin, dinotefuran, thiacloprid, thiamethoxam, imidacloprid, and nitenpyram); four OP metabolites (dialkylphosphates [DAPs]), including dimethylphosphate, dimethylthiophosphate, diethylphosphate, and diethylthiophosphate; and three PYR metabolites (3-phenoxybenzoic acid, trans-chrysanthemumdicarboxylic acid, and 3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropane carboxylic acid). Urine samples were collected from 223 children (108 males and 115 females) in the summer and winter months. The detection rates of NEOs were 58% for dinotefuran, 25% for thiamethoxam, 21% for nitenpyram, and <16% for all other NEOs. The median and maximum concentrations of the sum of the seven NEOs (ΣNEO) were 4.7 and 370.2nmol/g creatinine, respectively. Urinary ΣNEO, dimethylphosphate, and all PYR metabolite concentrations were significantly higher in the summer than in the winter (p<0.05). The creatinine-adjusted concentration of ΣNEO significantly correlated with those of all DAPs (p<0.05) but not with those of the PYR metabolites. Moreover, the NEO-detected group showed higher urinary ΣDAP (sum of four OP metabolites) concentrations than the group without NEO detection. These findings suggest that children in Japan are environmentally exposed to the three major insecticide lines, and that the daily exposure sources of NEOs are common to those of OPs.

Temporal Levels of Urinary Neonicotinoid and Dialkylphosphate Concentrations in Japanese Women Between 1994 and 2011.

Over the last two decades, usage of neonicotinoid (NEO) insecticides has increased due to their high selectivity for insects versus mammals and their effectiveness for extermination of insects resistant to conventional pesticides such as pyrethroids and organophosphates (OPs). However, historical change of the NEO exposure level in humans is poorly understood. The aim of this study is to reveal changes in the levels of NEO and OP exposure in the human body over the last two decades using biomonitoring technique. We quantified urinary concentrations of 7 NEOs (acetamiprid, clothianidin, dinotefuran, imidacloprid, nitenpyram, thiacloprid, and thiamethoxam) and 4 metabolites of OPs (dimethylphosphate, dimethylthiophosphate, diethylphosphate, and diethylthiophosphate) in 95 adult females aged 45-75 in 1994, 2000, 2003, 2009, and 2011 (n = 17-20 different individuals in each year). The results show that the detection rates of urinary NEOs in Japanese women increased significantly between 1994 and 2011, suggesting that intakes of NEOs into the human body rose during that period. In contrast, exposure to OPs having O,O-dimethyl moieties decreased steadily according to a finding that geometric means of urinary dimethylphosphate concentrations kept diminishing considerably. These changes may reflect the amounts of NEOs and OPs used as insecticides in Japan.

Treatment of pediatric lymphoma in Japan: Current status and plans for the future.

Results of pediatric lymphoma treatment have improved markedly over the past 30 years. In Hodgkin's lymphoma, the 5 year event-free survival (EFS) was 81.5% in a retrospective study. In the ALB-NHL03 study, the 5 year EFS according to clinical stage in patients with lymphoblastic T-cell lymphoma (T-LBL) was 70.6% for stage III and 88.9% for stage IV. In mature B-cell lymphoma, the B-NHL03 study indicated that the 4 year EFS according to treatment group was 94% for group 1, 98% for group 2, 84% for group 3, and 78% for group 4. Moreover, the 2 year EFS rate was 81% in Japanese advanced stage patients based on the international ALCL99 study. Thus, EFS >80% was achieved in any subtype of pediatric lymphoma. With regard to refractory or recurrent lymphoma, however, treatment methods for improvement of the survival rate in these patients still need to be developed. Also the difference between child, and adolescent and young adult patients still needs to be clarified, and treatment protocols developed. Although lymphoma treatment does not greatly change according to country, it does differ between other countries and Japan for some subtypes of lymphoma. In particular, the results of treatment of stage III T-LBL in Japan are worse than those in the USA and Europe. The priority in future studies will be to collect data on these differences, and the reasons for these differences.

Biochemical staging of the chronic hepatic lesions of Wilson disease.

BACKGROUND: Copper toxicity steadily affects the livers of patients with Wilson disease. However, the toxic effect of copper on serum aspartate and alanine aminotransferase levels remains to be clarified as a prerequisite for diagnostic tests. The clinical records of 33 cases were analyzed to clarify the natural history of Wilson disease. Phenotypes were simplified into hepatic, acute, and neurologic. The bio-low stage of both enzymes was less than 40 IU/L, the bio-moderate stage was intermediate between 40 and 200 IU/L, and the bio-high stage was more than 200 IU/L of either or both enzymes. Rebounded enzyme levels at the recovery period from anemia were presumed to be the chronic baselines when pre-anemic enzyme levels were not available in the acute phenotype. We investigated whether these enzyme levels may provide information useful for screening patients. The natural history of chronic Wilson disease consisted of the first increasing and second decreasing phases. The clinical courses of a 4-year-old boy and 12-year-old girl were representative of the 2 phases, respectively. All but one patient were in the decreasing phase. Negative correlations were obtained between age and enzyme level in the decreasing phase. The hepatic phenotype may be a prototype found throughout the 2 phases, and acute and neurologic phenotypes may be major complications in the bio-moderate and bio-low stages of the decreasing phase, respectively. Biochemical staging may provide a better understanding of Wilson disease when combined with phenotypes. Bio-high stage patients should be referred to a medical center for diagnosis.

A revised method for determination of dialkylphosphate levels in human urine by solid-phase extraction and liquid chromatography with tandem mass spectrometry: application to human urine samples from Japanese children.

OBJECTIVES: Biological monitoring of organophosphorus insecticide (OP) metabolites, specifically dialkylphosphates (DAP) in urine, plays a key role in low-level exposure assessment of OP in individuals. The aims of this study are to develop a simple and sensitive method for determining four urinary DAPs using high-performance liquid chromatography with tandem mass spectrometry (LC-MS/MS), and to assess the concentration range of urinary DAP in Japanese children. METHODS: Deuterium-labeled DAPs were used as internal standards. Urinary dimethylphosphate (DMP) and diethylphosphate (DEP), which passed through the solid-phase extraction (SPE) column, and dimethylthiophosphate (DMTP) and diethylthiophosphate (DETP), which were extracted from a SPE column using 2.5 % NH3 water including 50 % acetonitrile, were prepared for separation analysis. The samples were then injected into LC-MS/MS. The optimized method was applied to spot urine samples from 3-year-old children (109 males and 116 females) living in Aichi Prefecture in Japan. RESULTS: Results from the validation study demonstrated good within- and between-run precisions (<10.7 %) with low detection limits (0.4 for DMP and DMTP, 0.2 for DEP and 0.1 µg/L for DETP). The geometric mean values and detection rates of the urinary DAPs in Japanese children were 14.4 µg/L and 100 % for DMP, 5.3 µg/L and 98 % for DMTP, 5.5 µg/L and 99 % for DEP, and 0.6 µg/L and 80 % for DETP, respectively. CONCLUSIONS: The present high-throughput method is simple and reliable, and can thereby further contribute to development of an exposure assessment of OP. The present study is the first to reveal the DAP concentrations in young Japanese children.

Evaluating the risk of phthalate and non-phthalate plasticizers in dust samples from 100 Japanese houses.

Phthalates are widely used as plasticizer and associated with various health issues. Recently, non-phthalate plasticizers are replacing phthalates; however, the exposure to these substances and the risk in Japan is unclear. In this study, we assessed the concentrations of phthalates, non-phthalate plasticizers, and phthalate degradation products in house dust and determined their respective exposure risks via oral and dermal routes. Twelve phthalates, seven non-phthalate plasticizers, and two degradation products were determined in the house dust obtained from 100 Japanese homes. The median concentration of di(2-ethylhexyl) phthalate (DEHP), accounting for 85 % of the total concentration of phthalates and non-phthalate plasticizers detected in this study, was 2.1 × 103 µg/g of dust. Apart from DEHP, diisononyl phthalate (DINP) and di(2-ethylhexyl) terephthalate (DEHT) were the most abundant in the house dust, accounting for 6.2 % (median: 1.7 × 102 µg/g of dust) and 6.1 % (median: 1.7 × 102 µg/g of dust) of the total concentrations, respectively. DEHP and DEHT concentrations in house dust were higher in apartment and small houses (floor area: ≤30 m2 or 31-60 m2 for DEHP and 31-60 m2 for DEHT) than in detached and large houses (floor area: ≥121 m2). Conversely, di-n-butyl phthalate (DnBP) concentrations were significantly higher in detached and large houses (floor area: ≥121 m2) than in apartment and small houses (floor area: ≤30 m2). The total hazard quotient (HQ), using the maximum concentration in house dust, revealed that oral and dermal exposure to house dust was 1.3 × 10-6-0.11 for adults (all substances) and 1.6 × 10-5-2.2 × 10-2 for preschool children (except for DnBP and DEHP), suggesting no risk. The HQs for DnBP and DEHP exposure via house dust for preschool children using the maximum values were 0.46 and 1.2, and 6.0 × 10-3 and 0.18 using the median values, indicating that risk of DEHP exposure should be exhaustively determined by considering other exposure routes that were not evaluated in this study, such as diet.