Temporal trends in exposure to parabens, benzophenones, triclosan, and triclocarban in adult females in Kyoto, Japan, from 1993 to 2016.

Products used in daily life can contain chemicals such as parabens, benzophenones, triclosan, and triclocarban that have potential endocrine-disrupting effects. Little is known about the temporal trends of exposure levels to some of these chemicals in Japan. Our study assessed the intake and risk associated with exposure to commonly used chemicals. We measured the concentrations of five parabens, four benzophenones, and triclosan and triclocarban in 133 single spot urine samples. The urine samples were collected in 1993, 2000, 2003, 2009, 2011, and 2016 from healthy female residents in Kyoto, Japan. With the exception of methylparaben, ethylparaben, and butylparaben, there were no significant fluctuations in the concentrations of target chemicals over the study period; however, methylparaben, ethylparaben, and butylparaben showed temporal changes in concentrations. Methylparaben concentrations peaked in 2003 with a median value of 309 µg/g creatinine, ethylparaben concentrations peaked in 1993 with a median value of 17.3 µg/g creatinine, and butylparaben showed a decline, with the median values becoming non-detectable in 2009 and 2016. We calculated estimated daily intakes and hazard quotients for each chemical. In the analysis of total samples, 2.3% (3 samples) for butylparaben and 0.8% (1 sample) for propylparaben were found to surpass a hazard quotient of 1. Overall, 3% (n = 4) of the study participants exceeded a hazard index of 1. The potential health risks associated with exposure to butylparaben and propylparaben emphasize the need for further monitoring and research.

Mesothelioma carcinogenesis of chrysotile and forsterite compared and validated by intraperitoneal injection in rat.

Asbestos, especially chrysotile, continues to be exposed to humans globally. Hence, it should be disposed properly to prevent asbestos-related diseases, including mesothelioma and lung cancer. This study aimed to verify whether forsterite, a heating product of chrysotile, can cause carcinogenicity, particularly mesothelioma. Forsterite (FO-1000) and enstatite (EN-1500) produced by heating chrysotile at 1000°C and 1500°C, respectively, were subjected. We injected 10 mg of chrysotile, FO-1000, or EN-1500 in rats intraperitoneally and observed the development of peritoneal mesothelioma until 24 months. The incidence of peritoneal mesothelioma in the chrysotile group was 91.2%, whereas in the FO-1000 and EN-1500 groups, peritoneal mesothelioma did not develop. Urinary 8-hydroxy-2'-deoxyguanosine and serum N-ERC/mesothelin concentrations significantly increased in the chrysotile group that developed peritoneal mesothelioma, while they only temporarily changed in the FO-1000 or EN-1500 groups during early treatment. Furthermore, there was a significant homozygous deletion of the CDKN2A/p16 gene in the chrysotile group compared to the control group, in contrast to no significant difference in the FO-1000 and EN-1500 groups. Therefore, this study provides clear evidence that forsterite is a nonmesothelioma carcinogen and suggests that forsterite and enstatite are sufficient substances for chrysotile detoxification.

Role of ABCB1 and ABCB4 in renal and biliary excretion of perfluorooctanoic acid in mice.

BACKGROUND: Perfluorooctanoic acid (PFOA) is one of the major per- and polyfluoroalkyl substances. The role of ATP-binding cassette (ABC) transporters in PFOA toxicokinetics is unknown. METHODS: In this study, two ABC transporters, ABCB1 and ABCB4, were examined in mice with single intravenous PFOA administration (3.13 µmol/kg). To identify candidate renal PFOA transporters, we used a microarray approach to evaluate changes in gene expression of various kidney transporters in Abcb4 null mice. RESULTS: Biliary PFOA concentrations were lower in Abcb4 null mice (mean ± standard deviation: 0.25 ± 0.12 µg/mL) than in wild-type mice (0.87 ± 0.02 µg/mL). Immunohistochemically, ABCB4 expression was confirmed at the apical region of hepatocytes. However, renal clearance of PFOA was higher in Abcb4 null mice than in wild-type mice. Among 642 solute carrier and ABC transporters, 5 transporters showed significant differences in expression between wild-type and Abcb4 null mice. These candidates included two major xenobiotic transporters, multidrug resistance 1 (Abcb1) and organic anion transporter 3 (Slc22a8). Abcb1 mRNA levels were higher in Abcb4 null mice than in wild-type mice in kidney. In Abcb4 null mice, Abcb1b expression was enhanced in proximal tubules immunohistochemically, while that of Slc22a8 was not. Finally, in Abcb1a/b null mice, there was a significant decrease in the renal clearance of PFOA (0.69 ± 0.21 vs 1.1 mL ± 0.37/72 h in wild-type mice). A homology search of ABCB1 showed that several amino acids are mutated in humans compared with those in rodents and monkeys. CONCLUSIONS: These findings suggest that, in the mouse, Abcb4 and Abcb1 are excretory transporters of PFOA into bile and urine, respectively.

Evaluation of arsenic metabolism and tight junction injury after exposure to arsenite and monomethylarsonous acid using a rat in vitro blood-Brain barrier model.

Experimental verification of impairment to cognitive abilities and cognitive dysfunction resulting from inorganic arsenic (iAs) exposure in children and adults is challenging. This study aimed to elucidate the effects of arsenite (iAsIII; 1, 10 and 20 µM) or monomethylarsonous acid (MMAIII; 0.1, 1 and 2 µM) exposure on arsenic metabolism and tight junction (TJ) function in the blood-brain barrier (BBB) using a rat in vitro-BBB model. The results showed that a small percentage (~15%) of iAsIII was oxidized or methylated within the BBB, suggesting the persistence of toxicity as iAsIII. Approximately 65% of MMAIII was converted to low-toxicity monomethylarsonic acid and dimethylarsenic acid via oxidation and methylation. Therefore, it is estimated that MMAIII causes TJ injury to the BBB at approximately 35% of the unconverted level. TJ injury of BBB after iAsIII or MMAIII exposure could be significantly assessed from decreased expression of claudin-5 and decreased transepithelial electrical resistance values. TJ injury in BBB was found to be significantly affected by MMAIII than iAsIII. Relatedly, the penetration rate in the BBB by 24 h of exposure was higher for MMAIII (53.1% ± 2.72%) than for iAsIII (43.3% ± 0.71%) (p < 0.01). Exposure to iAsIII or MMAIII induced an antioxidant stress response, with concentration-dependent increases in the expression of nuclear factor-erythroid 2-related factor 2 in astrocytes and heme oxygenase-1 in a group of vascular endothelial cells and pericytes, respectively. This study found that TJ injury at the BBB is closely related to the chemical form and species of arsenic; we believe that elucidation of methylation in the brain is essential to verify the impairment of cognitive abilities and cognitive dysfunction caused by iAs exposure.

Temporal trends in bisphenol exposures and associated health risk among Japanese women living in the Kyoto area from 1993 to 2016.

BACKGROUND: Bisphenols, and especially bisphenol A, are widely used as components of epoxy resins and polycarbonate. Widespread detection and potential health risks have led to bisphenol A being replaced by other alternatives, including structurally similar bisphenol analogs. Several bisphenol analogs are suspected to have similar adverse health consequences. This study examined the temporal trends in bisphenol exposure among a group of Japanese women from 1993 to 2016, and assessed the associated health risks. METHODS: We used archived single spot urine samples of healthy Japanese women living in the Kyoto area (n = 133) collected in 1993, 2000, 2003, 2009, 2011, and 2016. We measured the concentrations of 10 bisphenols in these samples. RESULTS: A sharp increase in the detection rates of bisphenol F was observed after 2000. There was a distinct downward trend in urinary bisphenol A concentrations and an upward trend in bisphenol E concentrations after 2009. While the hazard index for all measured bisphenols was below 1 in all subjects, bisphenol F was determined as the most important risk driver after 2000, rather than bisphenol A. DISCUSSION: Trends of decreasing bisphenol A and increasing bisphenol E exposure especially after 2011, along with no significant change in the sum of all bisphenol analogs in urine, provide clear evidence that bisphenol A has been replaced by other bisphenols in the study population. We found no significant change in the total exposure to bisphenols during the study period. Bisphenol F might become the most important bisphenol in terms of risk, while cumulative risks due to all bisphenol exposure were deemed insignificant. Considering the accumulating evidence indicating adverse effects at lower exposure levels, further studies are warranted to assess exposure and risk from bisphenol A analogs.

Exposure to phthalate esters in Japanese females in Kyoto, Japan from 1993 to 2016: Temporal trends and associated health risks.

Phthalates are used as plasticizers in many products used in daily life worldwide. Due to industrial and economic developments, exposure among general population to phthalates may vary geographically and temporally. However, studies are lacking for investigating temporal changes in phthalate exposure in the Japanese population. In the present study, the temporal trends in exposure to various phthalates were assessed among a group of Japanese adult female population over 1993-2016 and derived associated risks. For this purpose, urine samples of healthy Japanese females in Kyoto, Japan (N = 132) collected in 1993, 2000, 2003, 2009, 2011, and 2016, were employed and measured for the concentrations of 18 phthalate metabolites. Over this period, the detection rates of mono(3-carboxypropyl) phthalate (MCPP) and monoisobutyl phthalate (MiBP) decreased, and the geometric means of the urinary concentrations of mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) showed a significant decreasing trend. Cumulative risk due to exposure to dibutyl phthalate (DBP), diisobutyl phthalate (DiBP), butyl benzyl phthalate (BBP), and di-2-ethylhexyl phthalate (DEHP) showed a dramatic decrease only between 1993 and 2000. The maximum hazard quotient (HQM) was attributed to DEHP in most subjects regardless of sampling year. This study showed the temporal trend of the exposure of Japanese females to several phthalate esters over two decades. As of the late 2010's, DEHP was still the predominant component of phthalate ester exposure in the population. The HI value, however, indicates that direct risk due to phthalate exposure was unlikely among the studied population.

Characterization of Moyamoya and Middle Cerebral Artery Diseases by Carotid Canal Diameter and RNF213 p.R4810K Genotype.

OBJECTIVES: It is sometimes difficult to differentiate middle cerebral artery disease from moyamoya disease because the two can present similarly yet have different treatment strategies. We investigated whether the presence of a narrow carotid canal and the RNF213 mutation can help differentiate between the two phenotypes. POPULATION AND METHODS: We analyzed 78 patients with moyamoya disease, 27 patients with middle cerebral artery disease, and 79 controls from 2 facilities. The carotid canal diameter was measured using computed tomography. The p.R4810K mutation was genotyped by TaqMan assay. A receiver operating characteristics analysis was performed to assess the significance of the carotid canal diameter for the accurate diagnosis of moyamoya disease. RESULTS: The carotid canal diameter was significantly narrower in patients with moyamoya disease than in controls. The optimal cutoff values were 5.0 mm for adult males and 4.5 mm for adult females and children (sensitivity: 0.82; specificity: 0.92). Among the patients with middle cerebral artery disease, 18.5% and 25.0% of the affected hemispheres had the p.R4810K mutation and narrow canal (i.e., below the cutoff), respectively, whereas only 3.1% of those had both. Contrastingly, 68.8% of the affected hemispheres in patients with moyamoya disease had both these characteristics. Among the patients with moyamoya disease, those with the p.R4810K mutation tended to have narrower carotid canals. CONCLUSIONS: Although the presence of a narrow carotid canal or the p.R4810K mutation alone could not be used to distinguish those with moyamoya disease from those with middle cerebral artery disease, the combination of these factors could better characterize the two phenotypes.

Systematic Review Protocol for the Current State of Chemical Exposure in Infants via Breast Milk, Artificial Milk and Dairy Products.

Many studies have shown that human breast milk is contaminated with various chemicals. In the proposed systematic review, the aim is to identify and summarize the available literature regarding chemical exposure via breastfeeding or the feeding of artificial formula. MEDLINE (PubMed) will be the primary source in this literature search. Primary studies that analyzed one or more chemicals of interest in breast milk or artificial milk and that reported information on concentrations will be eligible for this review. Conference abstracts will not be included in the review unless access to the data is easy. First, the titles and abstracts of identified articles will be screened by two or more researchers. Then, a full-text review will be conducted to extract data from the included articles and code them for classification. The results of the search and classification will be summarized narratively and bibliometrically. The aim of the review is to analyze trends in publications according to year and region from the viewpoint of target chemicals, location, range of concentrations, and health outcomes.

Systematic evaluation of exposure to trace elements and minerals in patients with chronic kidney disease of uncertain etiology (CKDu) in Sri Lanka.

Chronic kidney disease of uncertain etiology (CKDu) in areas in and around Sri Lanka's North Central Province has been identified as a major non-communicable disease due to its high prevalence and the burden on the public health system. Controversial evidence relating to the etiology and risk factors of CKDu has been reported. The most debated is the role of trace elements such as Cd and As in the pathogenesis of CKDu. Urine and hair samples collected from CKDu patients and healthy controls were measured for the concentration of different elements including Cd and As. To assess the possible environmental exposures, drinking water and rice samples collected from the affected areas as well as unaffected areas in the country were analyzed. Transmission electronic microscopic analysis of renal biopsies from CKDu patients was also performed. Analysis of drinking water and rice samples indicated that the levels of all minerals and trace elements analyzed including Cd and As were within the levels recommended by World Health Organization and Sri Lanka drinking water guidelines and did not suggest any form of contamination. Analysis of biological samples, including urine, hair and renal tissue, did not provide evidence to support Cd or As toxicity in CKDu patients. Overall, the observations of this integrated, comprehensive study, which included biological, environmental and pathological investigations, strongly support our previous reports on the absence of Cd and As toxicity in areas with high prevalence of CKDu. Further, these observations do not provide evidence on the involvement of Cd and As in pathogenesis of CKDu in Sri Lanka.

RNF213 p.R4810K Variant and Intracranial Arterial Stenosis or Occlusion in Relatives of Patients with Moyamoya Disease.

BACKGROUND: This study aimed to determine the effectiveness of genetic testing for the p.R4810K variant (rs112735431) of the Mysterin/RNF213 gene, which is associated with moyamoya disease and other intracranial vascular diseases, in the family members of patients with moyamoya disease. METHODS: We performed genotyping of the RNF213 p.R4810K polymorphism and magnetic resonance angiography on 59 relatives of 18 index patients with moyamoya disease. Nineteen individuals had follow-up magnetic resonance angiography with a mean follow-up period of 7.2 years. RESULTS: Six of the 34 individuals with the GA genotype (heterozygotes for p.R4810K) showed intracranial steno-occlusive lesions in the magnetic resonance angiography, whereas none of the 25 individuals with the GG genotype (wild type) showed any abnormalities. Follow-up magnetic resonance angiography revealed de novo lesions in 2 and disease progression in 1 of the 11 individuals with the GA genotype, despite none of the 8 individuals with the GG genotype showing any changes. Accordingly, 8 individuals had steno-occlusive lesions at the last follow-up, and all had the p.R4810K risk variant. The prevalence of steno-occlusive intracranial arterial diseases in family members with the p.R4810K variant was 23.5% (95% confidence interval: 9.27%-37.78%), which was significantly higher than in those without the variant (0%, P = .0160). CONCLUSIONS: Genotyping of the p.R4810K missense variant is useful for identifying individuals with an elevated risk for steno-occlusive intracranial arterial diseases in the family members of patients with moyamoya disease.

Lactational exposure to short-chain chlorinated paraffins in China, Korea, and Japan.

To investigate short-chain chlorinated paraffin (SCCP) levels in human breast milk, pooled breast milk samples (BMSs) collected between 2007 and 2010 from Chinese (Beijing, n = 17), Korean (Seoul, Busan, n = 16), and Japanese (Kyoto, Sendai, n = 44) women were analyzed. SCCPs found in air samples in Beijing (n = 4, in 2008) were also analyzed and compared with BMSs to estimate the possible source of contamination in Beijing. The electron-capture negative ionization method demonstrated the different sensitivities for SCCPs, and pentachlorinated alkanes had the highest method detection limit (MDL) among congeners. In Beijing, SCCPs were detected in 8 of 17 pooled BMSs at concentrations more than the highest MDL of each homolog. The total SCCP concentration ranged from below the MDL to 54 ng g-1 lipid weight. Among the SCCP homologs, polychlorinated tridecanes were most frequently detected in Beijing. In Korea and Japan, no samples contained detectable total SCCP concentrations at more than the highest MDL. In Seoul, only two samples showed trace levels of polychlorinated undecanes. In Kyoto and Sendai, congeners of polychlorinated dodecanes were most frequently detected. C10 components were the major contributors to the SCCPs in the atmosphere of Beijing. Congener profiles in breast milk in Beijing provided a clear contrast to the profiles found in food and air. The unique congener profiles necessitate the monitoring of breast milk for exposure of infants to SCCPs. The calculated mean exposure of SCCPs in 1-year-olds in China was 337 ng (kg body weight)-1 d-1. These results demonstrate the body burden of SCCPs in the study areas and potential lactational exposure to SCCPs in Asian countries.

RNF213 Is Associated with Intracranial Aneurysms in the French-Canadian Population.

Intracranial aneurysms (IAs) are the result of focal weakness in the artery wall and have a complex genetic makeup. To date, genome-wide association and sequencing studies have had limited success in identifying IA risk factors. Distinct populations, such as the French-Canadian (FC) population, have increased IA prevalence. In our study, we used exome sequencing to prioritize risk variants in a discovery cohort of six FC families affected by IA, and the analysis revealed an increased variation burden for ring finger protein 213 (RNF213). We resequenced RNF213 in a larger FC validation cohort, and association tests on further identified variants supported our findings (SKAT-O, p = 0.006). RNF213 belongs to the AAA+ protein family, and two variants (p.Arg2438Cys and p.Ala2826Thr) unique to affected FC individuals were found to have increased ATPase activity, which could lead to increased risk of IA by elevating angiogenic activities. Common SNPs in RNF213 were also extracted from the NeuroX SNP-chip genotype data, comprising 257 FC IA-affected and 1,988 control individuals. We discovered that the non-ancestral allele of rs6565666 was significantly associated with the affected individuals (p = 0.03), and it appeared as though the frequency of the risk allele had changed through genetic drift. Although RNF213 is a risk factor for moyamoya disease in East Asians, we demonstrated that it might also be a risk factor for IA in the FC population. It therefore appears that the function of RNF213 can be differently altered to predispose distinct populations to dissimilar neurovascular conditions, highlighting the importance of a population's background in genetic studies of heterogeneous disease.

PTP1B controls non-mitochondrial oxygen consumption by regulating RNF213 to promote tumour survival during hypoxia.

Tumours exist in a hypoxic microenvironment and must limit excessive oxygen consumption. Hypoxia-inducible factor (HIF) controls mitochondrial oxygen consumption, but how/if tumours regulate non-mitochondrial oxygen consumption (NMOC) is unknown. Protein-tyrosine phosphatase-1B (PTP1B) is required for Her2/Neu-driven breast cancer (BC) in mice, although the underlying mechanism and human relevance remain unclear. We found that PTP1B-deficient HER2(+) xenografts have increased hypoxia, necrosis and impaired growth. In vitro, PTP1B deficiency sensitizes HER2(+) BC lines to hypoxia by increasing NMOC by α-KG-dependent dioxygenases (α-KGDDs). The moyamoya disease gene product RNF213, an E3 ligase, is negatively regulated by PTP1B in HER2(+) BC cells. RNF213 knockdown reverses the effects of PTP1B deficiency on α-KGDDs, NMOC and hypoxia-induced death of HER2(+) BC cells, and partially restores tumorigenicity. We conclude that PTP1B acts via RNF213 to suppress α-KGDD activity and NMOC. This PTP1B/RNF213/α-KGDD pathway is critical for survival of HER2(+) BC, and possibly other malignancies, in the hypoxic tumour microenvironment.

Infantile Pain Episodes Associated with Novel Nav1.9 Mutations in Familial Episodic Pain Syndrome in Japanese Families.

Painful peripheral neuropathy has been correlated with various voltage-gated sodium channel mutations in sensory neurons. Recently Nav1.9, a voltage-gated sodium channel subtype, has been established as a genetic influence for certain peripheral pain syndromes. In this study, we performed a genetic study in six unrelated multigenerational Japanese families with episodic pain syndrome. Affected participants (n = 23) were characterized by infantile recurrent pain episodes with spontaneous mitigation around adolescence. This unique phenotype was inherited in an autosomal-dominant mode. Linkage analysis was performed for two families with 12 affected and nine unaffected members, and a single locus was identified on 3p22 (LOD score 4.32). Exome analysis (n = 14) was performed for affected and unaffected members in these two families and an additional family. Two missense variants were identified: R222H and R222S in SCN11A. Next, we generated a knock-in mouse model harboring one of the mutations (R222S). Behavioral tests (Hargreaves test and cold plate test) using R222S and wild-type C57BL/6 (WT) mice, young (8-9 weeks old; n = 10-12 for each group) and mature (36-38 weeks old; n = 5-6 for each group), showed that R222S mice were significantly (p < 0.05) more hypersensitive to hot and cold stimuli than WT mice. Electrophysiological studies using dorsal root ganglion neurons from 8-9-week-old mice showed no significant difference in resting membrane potential, but input impedance and firing frequency of evoked action potentials were significantly increased in R222S mice compared with WT mice. However, there was no significant difference among Nav1.9 (WT, R222S, and R222H)-overexpressing ND7/23 cell lines. These results suggest that our novel mutation is a gain-of-function mutation that causes infantile familial episodic pain. The mouse model developed here will be useful for drug screening for familial episodic pain syndrome associated with SCN11A mutations.

Biological Monitoring of Human Exposure to Neonicotinoids Using Urine Samples, and Neonicotinoid Excretion Kinetics.

BACKGROUND: Neonicotinoids, which are novel pesticides, have entered into usage around the world because they are selectively toxic to arthropods and relatively non-toxic to vertebrates. It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults. METHODOLOGY/PRINCIPAL FINDINGS: Deuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53-3.66 µg/day. The highest intake of any of the neonicotinoids in the study population was 64.5 µg/day for dinotefuran, and this was <1% of the acceptable daily intake.

A new horizon of moyamoya disease and associated health risks explored through RNF213.

The cerebrovascular disorder moyamoya disease (MMD) was first described in 1957 in Japan, and is typically considered to be an Asian-specific disease. However, it is globally recognized as one of the major causes of childhood stroke. Although several monogenic diseases are known to be complicated by Moyamoya angiopathy, the ring finger protein 213 gene (RNF213) was identified as a susceptibility gene for MMD. RNF213 is unusual, because (1) it induces MMD with no other recognizable phenotypes, (2) the RNF213 p.R4810K variant is an Asian founder mutation common to Japanese, Korean and Chinese with carrier rates of 0.5-2% of the general population but a low penetrance, and (3) it encodes a relatively largest proteins with a dual AAA+ ATPase and E3 Ligase activities. In this review, we focus on the genetics and genetic epidemiology of RNF213, the pathology of RNF213 R4810K, and the molecular functions of RNF213, and also address the public health contributions to current unresolved issues of MMD. We also emphasize the importance of a more updated definition for MMD, of qualified cohort studies based on genetic epidemiology and an awareness of the ethical issues associated with genetic testing of carriers.

Neonicotinoid concentrations in urine from chronic kidney disease patients in the North Central Region of Sri Lanka.

OBJECTIVES: Neonicotinoid insecticides have been widely used around the world since the 1990s. Reports have been made since the 1990s of rice paddy farmers in the North Central Region (NCR) of Sri Lanka suffering from chronic kidney disease with unknown etiology (CKDu). A preliminary evaluation of the exposure of local farmers in the NCR of Sri Lanka to neonicotinoids was performed. METHODS: We analyzed neonicotinoid and neonicotinoid metabolite concentrations in spot urine samples. We selected 40 samples, 10 from farmers with CKDu and 10 from controls from each of two areas, Medawachchiya and Girandurukotte. RESULTS: Imidacloprid and desmethyl-acetamiprid were found at significantly higher concentrations in the control samples (with medians of 51 ng/l and 340 ng/l, respectively) than in the CKDu samples (medians of 15 ng/l and 150 ng/l, respectively) when the results were not adjusted for the creatinine contents. None of the six compounds that were measured in the urine samples were found at significantly higher concentrations in the CKDu samples than in the control samples. None of the neonicotinoid concentrations in the samples analyzed in this study exceeded the concentrations that have been found in samples from the general population of Japan. CONCLUSIONS: Farmers (both with and without CKDu) living in CKDu-endemic areas in the NCR of Sri Lanka are exposed to lower neonicotinoid concentrations than non-occupationally exposed residents of Japan.

Biochemical and Functional Characterization of RNF213 (Mysterin) R4810K, a Susceptibility Mutation of Moyamoya Disease, in Angiogenesis In Vitro and In Vivo.

BACKGROUND: P.R4810K of RNF213 (mysterin: rs112735431), which is an AAA(+) ATPase, is the susceptibility polymorphism for moyamoya disease (MMD) in East Asians. However, the role of RNF213 R4810K in the etiology of MMD is unknown. METHODS AND RESULTS: To clarify the role of RNF213 in known angiogenic pathways, RNF213 expression was analyzed in endothelial cells (ECs) treated with several angiogenic and antiangiogenic factors, including interferons (IFNs). RNF213 was upregulated by IFN-ß through signal transducer and activator of transcription x in the promoter and mediated antiangiogenic activity of IFN-ß. RNF213 wild-type (WT) overexpression could not lower angiogenesis without IFN-ß, but RNF213 R4810K overexpression could. To correlate biochemical function as ATPase and the role of RNF213 oligomer formation with antiangiogenic activity, we investigated the effects of mutations in the AAA(+) module. A mutation of the Walker B motif (WEQ), which stabilizes oligomerization, inhibited angiogenesis, but AAA(+) module deletion, which cannot initiate oligomerization, did not. Intriguingly, R4810K, similar to WEQ, decreased ATPase activity, suggesting its antiangiogenic activity through stabilizing oligomers. To confirm the antiangiogenic effect of RNF213 upregulation in vivo, vascular EC- or smooth muscle cell-specific Rnf213 R4757K (R4810K ortholog) or WT transgenic (Tg) mice were exposed to hypoxia. Cerebral angiogenesis by hypoxia was suppressed in EC-specific Rnf213 R4757K Tg mice, whereas it was not suppressed in other mice. CONCLUSIONS: This study suggests the importance of inflammatory signals as environmental factors and R4810K carriers for susceptibility to cerebral hypoxia. A specific inhibitor of ATP binding to the first AAA(+) could be a promising therapeutic candidate for MMD.

Whole-exome sequencing reveals genetic variants associated with chronic kidney disease characterized by tubulointerstitial damages in North Central Region, Sri Lanka.

OBJECTIVES: The familial clustering observed in chronic kidney disease of uncertain etiology (CKDu) characterized by tubulointerstitial damages in the North Central Region of Sri Lanka strongly suggests the involvement of genetic factors in its pathogenesis. The objective of the present study is to use whole-exome sequencing to identify the genetic variants associated with CKDu. METHODS: Whole-exome sequencing of eight CKDu cases and eight controls was performed, followed by direct sequencing of candidate loci in 301 CKDu cases and 276 controls. RESULTS: Association study revealed rs34970857 (c.658G > A/p.V220M) located in the KCNA10 gene encoding a voltage-gated K channel as the most promising SNP with the highest odds ratio of 1.74. Four rare variants were identified in gene encoding Laminin beta2 (LAMB2) which is known to cause congenital nephrotic syndrome. Three out of four variants in LAMB2 were novel variants found exclusively in cases. CONCLUSION: Genetic investigations provide strong evidence on the presence of genetic susceptibility for CKDu. Possibility of presence of several rare variants associated with CKDu in this population is also suggested.

Perfluorinated carboxylic acids discharged from the Yodo River Basin, Japan.

We investigated perfluorinated carboxylic acids (PFCAs) with 7-14 carbon atoms (C7-C14) in the Yodo River system in 2013. C7-C11 were detected at most sampling sites. The range and median of total PFCAs (ΣPFCAs) concentrations were 1.0-89.7 and 11.2 ng L(-1), respectively. The dominant component was C8 (average for all samples=53.3±8.8%), followed by C7 (19.2±6.7%) and C9 (17.6±7.1%). The levels of C8 were confirmed to decrease greatly over the last 10 years. We assessed the fluxes in C7-C11 discharged from the basin based on the concentrations in river water and river flow rate. The flux of discharged ΣPFCAs was 237.0 g d(-1) at the most downriver point of the assessment areas. Considering the variability in flow rate due to precipitation, the annual ΣPFCAs flux was estimated to be 86.5-173.4 kg y(-1). Identification and quantification of PFCAs sources is difficult because the strength of the sources changes with time, and available information is quite limited. Further monitoring and investigation are necessary to understand sources of PFCAs, as well as their potential for human exposure.