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Tsuyoshi Sekizuka, Kentaro Itokawa, Rina Tanaka, Masanori Hashino, Koji Yatsu, Makoto Kuroda Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, 162-8640, JapanCorrespondence: Makoto Kuroda, Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjyuku, Tokyo, 162-8640, Japan, Tel +81-3-5285-1111, Fax +81-3-5285-1166, Email makokuro@niid.go.jpPurpose: Urban wastewater treatment plant (WWTP) effluents, even with proper treatment, may cause antimicrobial resistance (AMR) burden, with a high frequency of acquired antimicrobial resistance genes (ARGs). The dissemination of ARGs into the environment increases the risk of infectious diseases; however, there is little direct evidence regarding their epidemiological effects. This study aimed to assess effluents from urban WWTPs around the Tama River and Tokyo Bay using metagenomic analysis of (AMR) genes (ARGs) and heavy-metal resistance genes.Methods: Metagenomic DNA-seq analysis of water samples and resistome analysis were performed.Results: The most prevalent ARG was the sulfonamide resistance gene, sul1, followed by the quaternary ammonium compound resistance gene, qacE, suggesting that basic gene sets (sul1 and ∆qacE) in the class 1 integrons are the predominant ARGs. The aminoglycoside resistance genes, aadA and aph, and macrolide resistance genes, msr(E) and mph(E), were the predominant ARGs against each antimicrobial. blaOXA and blaGES were frequently detected, whereas the blaCTX-M cluster was faintly detected. Non-metric multidimensional scaling plot analysis and canonical correspondence analysis results suggested that marked differences in ARGs could be involved in the seasonal differences; qnrS2, aac(6’)-Ib, and mef(C) increased markedly in summer, whereas msr(E) was more frequently detected in winter. Heavy-metal (Hg and Cu) resistance genes (HMRGs) were significantly detected in effluents from all WWTPs.Conclusion: We characterized a baseline level of the environmental ARG/HMRG profile in the overall community, suggesting that environmental AMR surveillance, particularly in urban WWTPs, is a valuable first step in monitoring the AMR dissemination of bacteria from predominantly healthy individuals carrying notable ARG/Bs.Keywords: urban sewage, effluent, metagenomics, Enterobacteriaceae, ESBL, carbapenemase, heavy-metal resistance

Single-nucleotide polymorphisms (SNP) of ATP2B1 gene are associated with essential hypertension but their association with resistant hypertension (RHT) remains unexplored. The authors examined the relationship between ATP2B1 SNPs and RHT by genotyping 12 SNPs in ATP2B1 gene of 1124 Japanese individuals with lifestyle-related diseases. Patients with RHT had inadequate blood pressure (BP) control using three antihypertensive drugs or used ≥4 antihypertensive drugs. Patients with controlled hypertension had BP controlled using ≤3 antihypertensive drugs. The association between each SNP and RHT was analyzed by logistic regression. The final cohort had 888 (79.0%) and 43 (3.8%) patients with controlled hypertension and RHT, respectively. Compared with patients homozygous for the minor allele of each SNP in ATP2B1, a significantly higher number of patients carrying the major allele at 10 SNPs exhibited RHT (most significant at rs1401982: 5.8% vs. 0.8%, p = .014; least significant at rs11105378: 5.7% vs. 0.9%, p = .035; most nonsignificant at rs12817819: 5.1% vs. 10%, p = .413). After multivariate adjustment for age, sex, systolic BP, and other confounders, the association remained significant for rs2681472 and rs1401982 (OR: 7.60, p < .05 and OR: 7.62, p = .049, respectively). Additionally, rs2681472 and rs1401982 were in linkage disequilibrium with rs11105378. This study identified two ATP2B1 SNPs associated with RHT in the Japanese population. rs1401982 was most closely associated with RHT, and major allele carriers of rs1401982 required significantly more antihypertensive medications. Analysis of ATP2B1 SNPs in patients with hypertension can help in early prediction of RHT and identification of high-risk patients who are more likely to require more antihypertensive medications., (© 2024 The Authors. The Journal of Clinical Hypertension published by Wiley Periodicals LLC.)

Biosensors with two-dimensional materials have gained wide interest due to their high sensitivity. Among them, single-layer MoS 2 has become a new class of biosensing platform owing to its semiconducting property. Immobilization of bioprobes directly onto the MoS 2 surface with chemical bonding or random physisorption has been widely studied. However, these approaches potentially cause a reduction of conductivity and sensitivity of the biosensor. In this work, we designed peptides that spontaneously align into monomolecular-thick nanostructures on electrochemical MoS 2 transistors in a non-covalent fashion and act as a biomolecular scaffold for efficient biosensing. These peptides consist of repeated domains of glycine and alanine in the sequence and form self-assembled structures with sixfold symmetry templated by the lattice of MoS 2 . We investigated electronic interactions of self-assembled peptides with MoS 2 by designing their amino acid sequence with charged amino acids at both ends. Charged amino acids in the sequence showed a correlation with the electrical properties of single-layer MoS 2 , where negatively charged peptides caused a shift of threshold voltage in MoS 2 transistors and neutral and positively charged peptides had no significant effect on the threshold voltage. The transconductance of transistors had no decrease due to the self-assembled peptides, indicating that aligned peptides can act as a biomolecular scaffold without degrading the intrinsic electronic properties for biosensing. We also investigated the impact of peptides on the photoluminescence (PL) of single-layer MoS 2 and found that the PL intensity changed sensitively depending on the amino acid sequence of peptides. Finally, we demonstrated a femtomolar-level sensitivity of biosensing using biotinylated peptides to detect streptavidin.

Copper iodide (CuI) has emerged as a promising p-type semiconductor material owing to its excellent carrier mobility, high transparency, and solution processability. Although CuI has potential for numerous applications, including perovskite solar cells, photovoltaic devices, and thin-film transistors (TFTs), the close relationship between the anion vacancy generation and the charge transport mechanism in CuI-based devices is underexplored. In this study, we propose solution-processed p-type CuI TFTs which were subject to the thermal annealing process in air and vacuum atmospheres at temperatures of 100, 200, and 300 °C. The chemical states and surface morphologies of the CuI thin films were systematically investigated, revealing the generation of iodine vacancy states and the reduction of carrier concentration, as well as increased film density and grain size according to the annealing condition. Further, the effective role of the Al 2 O 3 passivation layer on the electrical characteristics of the solution-processed CuI TFTs is demonstrated for the first time, where the Al 2 O 3 precursor greatly enhanced the electrical performance of the CuI TFTs, exhibiting a field-effect mobility of 4.02 cm 2 /V·s, a subthreshold swing of 0.61 V/decade, and an on/off current ratio of 1.12 × 10 4 , which exceed the values of CuI TFTs reported so far. Based on the synergistic effects of the annealing process and the passivation layer that engineered the iodine vacancy state and morphology of CuI, the proposed CuI TFTs with the Al 2 O 3 passivation layer showed excellent reliability under 100 times repeated operation and long-term stability over 216 h, where the transfer curves slightly shifted in the positive direction of 1.36 and 1.88 V measured at a current level of 10 -6 A for the reliability and stability tests, respectively. Thus, this work opens a new window for solution-processed p-type CuI TFTs with excellent stability for developing next-generation complementary logic circuits.

To characterize environmental antimicrobial resistance (AMR) in urban areas, extended-spectrum β-lactamase- (ESBL)/carbapenemase-producing bacteria (EPB/CPB, respectively) from urban wastewater treatment plant effluents in Tokyo were isolated on CHROMagar ESBL plate. Complete genome sequence analysis, including plasmids, indicated that 126 CTX-M-positive isolates (31%) were identified among the 404 obtained isolates. The CTX-M-9 group was predominant ( n = 65, 52%), followed by the CTX-M-1 group ( n = 44, 35%). Comparative genome analysis revealed that CTX-M-27-positive E. coli O16:H5-ST131- fimH41 exhibited a stable genome structure and clonal-global dissemination. Plasmidome network analysis revealed that 304 complete plasmid sequences among 85 isolates were grouped into 14 incompatibility (Inc) network communities (Co1 to Co14). Co10 consisted of primarily IncFIA/IncFIB plasmids harboring bla CTX-M , whereas Co12 consisted primarily of IncFIA(HI1)/Inc FIB(K) plasmids harboring E. coli , whereas Co12 consisted primarily of IncFIA(HI1)/Inc FIB(K) plasmids harboring bla CTX-M , bla KPC , and bla GES in Klebsiella spp. Co11 was markedly located around Co10 and Co12. Co11 exhibited bla CTX-M , bla KPC , and bla NDM , and was mainly detected in E. coli and Klebsiella spp. from human and animal sources, suggesting a mutual role of Co11 in horizontal gene transfer between E. coli and Klebsiella spp. This comprehensive resistome analysis uncovers the mode of relational transfer among bacterial species, highlighting the potential source of AMR burden on public health in urban communities.

Background: We previously showed Lipin1 (LPIN1) to be a candidate gene for essential hypertension by genome-wide association studies. LPIN1 encodes the Lipin 1 protein, which contributes to the maintenance of lipid metabolism and glucose homeostasis. However, little is known about the association between LPIN1 and blood pressure (BP)., Methods: We evaluated the BP of LPIN1-deficient [fatty liver dystrophy (fld)] mice and explored related mechanisms., Results: Fld mice have very low expression of LPIN1 and exhibit fatty liver, hypertriglyceridemia, insulin resistance and peripheral neuropathy. Fld mice had significantly elevated SBP and heart rate (HR) throughout the day as measured by a radiotelemetric method. Diurnal variation of SBP and HR was also absent in fld mice. Furthermore, urinary excretion of adrenaline and noradrenaline by fld mice was significantly higher compared with that of control mice. The BP response of fld mice to clonidine (a centrally acting α2-adrenergic receptor agonist) was greater than that of control mice. However, levels of Angiotensinogen and Renin 1 mRNA and urinary nitric oxide excretion were comparable between the two groups. The decrease in SBP at 8 weeks after fat grafting surgery was significantly greater in the transplant group compared with the sham operated group., Conclusion: The elevated BP in fld mice may result from activation of the sympathetic nervous system through decreased levels of adipose cytokines. These results indicate that LPIN1 plays a crucial role in blood pressure regulation and that LPIN1 is a new target gene for essential hypertension., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Refractive changes are reportedly affected by age, sex, and current refractive error. To clarify the pattern of refractive changes in a Japanese population, we conducted a 5-year follow-up longitudinal analysis of spherical equivalent (SE) refractive changes with stratification by sex, age, and SE in 593,273 eyes from Japanese individuals ages 3-91 years. The 5-year SE change with myopic shift dramatically increased over time after age 4 years, and the largest change was observed in both males and females who were age 8 years at baseline [males: - 2.654 ± 0.048 diopters (D); females: - 3.110 ± 0.038 D]. During school age, the 5-year myopic change was greater in females than in males, and emmetropic and low-to-moderate myopic eyes underwent larger myopic changes than hyperopic and high-to-severe myopic eyes. After the peak at age 8 years, the 5-year myopic change gradually declined with age and fell below - 0.25 D at age 27 in males and age 26 years in females. The 5-year SE changes transitioned from a myopic to a hyperopic shift at age 51 in both sexes, and hyperopization advanced more quickly in hyperopic eyes. Our findings highlight the importance of myopia prevention in school-aged children., (© 2022. The Author(s).)

The worldwide eruption of coronavirus disease 2019 (COVID-19) that began in Wuhan, China in late 2019 reached 10 million cases by late June 2020. In order to understand the epidemiological landscape of the COVID-19 pandemic, many studies have attempted to elucidate phylogenetic relationships between collected viral genome sequences using haplotype networks. However, currently available applications for network visualization are not suited to understand the COVID-19 epidemic spatiotemporally due to functional limitations that motivated us to develop Haplotype Explorer, an intuitive tool for visualizing and exploring haplotype networks. Haplotype Explorer enables to dissect epidemiological consequences via interactive node filters and provides the perspective on infectious disease dynamics depend on regions and time, such as introduction, outbreak, expansion, and containment. Here, we demonstrate the effectiveness of Haplotype Explorer by showing features and an example of visualization. The demo using severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes are available at https://github.com/TKSjp/HaplotypeExplorer/blob/master/Example/. There are several examples using SARS-CoV-2 genomes and Dengue virus serotype 1 E-genes sequence., (© The Author(s) 2021. Published by Oxford University Press on behalf of Genetics Society of America.)

Chiral recognition of peptides on solid surfaces has been studied for a better understanding of their assembly mechanism toward its applications in stereochemistry and enantioselective catalysis. However, moving from small peptides such as dipeptides, understanding the chiral recognition of larger biomolecules such as oligopeptides or peptides with a larger sequence is challenging. Furthermore, their intrinsic mechanism for chiral recognition in liquid conditions was poorly investigated experimentally. Here, we used in/ex situ atomic force microscopy (AFM) to investigate the chiral recognition of self-assembled structures of l/d-type peptides on molybdenum disulfide (MoS 2 ). We chose single-layer MoS 2 with a triangular shape as a substrate for the self-assembly of peptides. The facet edges of MoS 2 were utilized as a landmark to identify the crystallographic orientation of their ordered structures. We found both peptide enantiomers formed nanowires on MoS 2 with a mirror symmetry according to the facet edges of MoS 2 . From in situ AFM measurements, we found a dimension of a unit cell in the self-assembled structure and proposed a model of lattice matching between peptides and MoS 2 lattice. The lattice matching for chiral recognition was further investigated by changing peptide sequences and surface lattice from MoS 2 to graphite. This work further deepened the understanding of biomolecular chiral recognition and will lead us to rationally design specific morphologies and conformations of chiral self-assembled structures of peptides with expected functions in the future.

After the first case of coronavirus disease 2019 (COVID-19) in Japan on 15 January 2020, multiple nationwide COVID-19 clusters were identified by the end of February. The Japanese government focused on mitigating the emerging COVID-19 clusters by conducting active nationwide epidemiological surveillance. However, an increasing number of cases continued to appear until early April 2020, many with unclear infection routes and no recent history of travel outside Japan. We aimed to evaluate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome sequences from the COVID-19 cases that appeared until early April 2020 and to characterize their genealogical networks in order to demonstrate possible routes of spread in Japan. Nasopharyngeal specimens were collected from patients, and reverse transcription-quantitative PCR tests for SARS-CoV-2 were performed. Positive RNA samples were subjected to whole-genome sequencing, and a haplotype network analysis was performed. Some of the primary clusters identified during January and February 2020 in Japan descended directly from the Wuhan-Hu-1-related isolates from China and other distinct clusters. Clusters were almost contained until mid-March; the haplotype network analysis demonstrated that the COVID-19 cases from late March through early April may have created an additional large cluster related to the outbreak in Europe, leading to additional spread within Japan. In conclusion, genome surveillance has suggested that there were at least two distinct SARS-CoV-2 introductions into Japan from China and other countries. IMPORTANCE This study aimed to evaluate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome sequences from COVID-19 cases and to characterize their genealogical networks to demonstrate possible routes of spread in Japan. We found that there were at least two distinct SARS-CoV-2 introductions into Japan, initially from China and subsequently from other countries, including Europe. Our findings can help understand how SARS-CoV-2 entered Japan and contribute to increased knowledge of SARS-CoV-2 in Asia and its association with implemented stay-at-home/shelter-in-place/self-restraint/lockdown measures. This study suggested that it is necessary to formulate a more efficient containment strategy using real-time genome surveillance to support epidemiological field investigations in order to highlight potential infection linkages and mitigate the next wave of COVID-19 in Japan., (Copyright © 2020 Sekizuka et al.)

Sarcoidosis is a genetically complex systemic inflammatory disease that affects multiple organs. We present a GWAS of a Japanese cohort (700 sarcoidosis cases and 886 controls) with replication in independent samples from Japan (931 cases and 1,042 controls) and the Czech Republic (265 cases and 264 controls). We identified three loci outside the HLA complex, CCL24, STYXL1-SRRM3, and C1orf141-IL23R, which showed genome-wide significant associations (P < 5.0 × 10 -8 ) with sarcoidosis; CCL24 and STYXL1-SRRM3 were novel. The disease-risk alleles in CCL24 and IL23R were associated with reduced CCL24 and IL23R expression, respectively. The disease-risk allele in STYXL1-SRRM3 was associated with elevated POR expression. These results suggest that genetic control of CCL24, POR, and IL23R expression contribute to the pathogenesis of sarcoidosis. We speculate that the CCL24 risk allele might be involved in a polarized Th1 response in sarcoidosis, and that POR and IL23R risk alleles may lead to diminished host defense against sarcoidosis pathogens.

In insects, the voltage-gated sodium channel (VGSC) is the primary target site of pyrethroid insecticides. Various amino acid substitutions in the VGSC protein, which are selected under insecticide pressure, are known to confer insecticide resistance. In the genome, the VGSC gene consists of more than 30 exons sparsely distributed across a large genomic region, which often exceeds 100 kbp. Due to this complex genomic structure, it is often challenging to genotype full coding nucleotide sequences (CDSs) of VGSC from individual genomic DNA (gDNA). In this study, we designed biotinylated oligonucleotide probes from CDSs of VGSC of Asian tiger mosquito, Aedes albopictus. The probe set effectively concentrated (>80,000-fold) all targeted regions of gene VGSC from pooled barcoded Illumina libraries each constructed from individual A. albopictus gDNAs. The probe set also captured all orthologous VGSC CDSs, except some tiny exons, from the gDNA of other Culicinae mosquitos, A. aegypti and Culex pipiens complex, with comparable efficiency as a result of the high nucleotide-level conservation of VGSC. To improve efficiency of the downstream bioinformatic process, we developed an automated pipeline-MoNaS (Mosquito Na+ channel mutation Search)-which calls amino acid substitutions in the VGSC from NGS reads and compares those to known resistance mutations. The proposed method and our bioinformatic tool should facilitate the discovery of novel amino acid variants conferring insecticide resistance on VGSC and population genetic studies on resistance alleles (with respect to the origin, selection, and migration etc.) in both clinically and agriculturally important insect pests., Competing Interests: The authors have declared that no competing interests exist.

Aeromonas hydrophila and Aeromonas caviae adapt to saline water environments and are the most predominant Aeromonas species isolated from estuaries. Here, we isolated antimicrobial-resistant (AMR) Aeromonas strains (A. hydrophila GSH8-2 and A. caviae GSH8M-1) carrying the carabapenemase bla KPC-2 gene from a wastewater treatment plant (WWTP) effluent in Tokyo Bay (Japan) and determined their complete genome sequences. GSH8-2 and GSH8M-1 were classified as newly assigned sequence types ST558 and ST13, suggesting no supportive evidence of clonal dissemination. The strains appear to have acquired bla KPC-2 -positive IncP-6-relative plasmids (pGSH8-2 and pGSH8M-1-2) that share a common backbone with plasmids in Aeromonas sp. ASNIH3 isolated from hospital wastewater in the United States, A. hydrophila WCHAH045096 isolated from sewage in China, other clinical isolates (Klebsiella, Enterobacter and Escherichia coli), and wastewater isolates (Citrobacter, Pseudomonas and other Aeromonas spp.). In addition to bla KPC-2 , pGSH8M-1-2 carries an IS26-mediated composite transposon including a macrolide resistance gene, mph(A). Although Aeromonas species are opportunistic pathogens, they could serve as potential environmental reservoir bacteria for carbapenemase and AMR genes. AMR monitoring from WWTP effluents will contribute to the detection of ongoing AMR dissemination in the environment and might provide an early warning of potential dissemination in clinical settings and communities., (© 2019 The Authors. Environmental Microbiology Reports published by Society for Applied Microbiology and John Wiley & Sons Ltd.)

Optimal blood pressure (BP) targets for hypertension have been an important clinical issue but have been elusive. The Systolic Blood Pressure Intervention Trial (SPRINT) showed significant benefits of intensive BP-lowering treatment with a target systolic BP level of < 120 mm Hg on major cardiovascular (CV) events and mortality, whereas there was a modest increase in renal events related to BP-lowering treatment. We searched the PubMed, Cochrane CENTRAL, and ICHUSHI databases for randomized trials that assigned participants to intensive versus usual BP-lowering treatment with different BP targets. The outcomes were major CV events, all-cause death, myocardial infarction, stroke, heart failure, renal events, and adverse events. Nineteen trials that enrolled a total of 55,529 participants with a mean follow-up duration ranging from 1.6 to 12.2 years were included in the present analysis. There was a significant reduction in major CV events, myocardial infarction, and stroke and a trend toward a reduction in heart failure associated with intensive BP-lowering treatment, but no differences in the risks of all-cause death, renal events, or adverse events were observed between the randomized groups. Subgroup analyses indicated that intensive BP-lowering treatment with a target of < 130/80 mm Hg and/or achievement of BP < 130/80 mm Hg were associated with a significant reduction in major CV events compared with the usual group. In conclusion, intensive BP-lowering treatment reduces the risk of CV events. A target BP level of < 130/80 mm Hg appears to be optimal for CV protection in patients with hypertension.

Antimicrobial resistance genes (ARGs) and the bacteria that harbor them are widely distributed in the environment, especially in surface water, sewage treatment plant effluent, soil, and animal waste. In this study, we isolated a KPC-2-producing Klebsiella pneumoniae strain (GSU10-3) from a sampling site in Tokyo Bay, Japan, near a wastewater treatment plant (WWTP) and determined its complete genome sequence. Strain GSU10-3 is resistant to most β-lactam antibiotics and other antimicrobial agents (quinolones and aminoglycosides). This strain is classified as sequence type 11 (ST11), and a core genome phylogenetic analysis indicated that strain GSU10-3 is closely related to KPC-2-positive Chinese clinical isolates from 2011 to 2017 and is clearly distinct from strains isolated from the European Union (EU), United States, and other Asian countries. Strain GSU10-3 harbors four plasmids, including a bla KPC-2 -positive plasmid, pGSU10-3-3 (66.2 kb), which is smaller than other bla KPC-2 -positive plasmids and notably carries dual replicons (IncFII [pHN7A8] and IncN). Such downsizing and the presence of dual replicons may promote its maintenance and stable replication, contributing to its broad host range with low fitness costs. A second plasmid, pGSU10-3-1 (159.0 kb), an IncA/C2 replicon, carries a class 1 integron (containing intI1 , dfrA12 , aadA2 , qacEΔ1 The plasmid pGSU10-3-2 (134.8 kb), an IncFII(K) replicon, carries the IS sul1 ) with a high degree of similarity to a broad-host-range plasmid present in the family Enterobacteriaceae The plasmid pGSU10-3-2 (134.8 kb), an IncFII(K) replicon, carries the IS 26 -mediated ARGs [ aac ( 6' ) Ib-cr,bla OXA-1 , catB4 (truncated), and aac (3) -IId ], tet (A), and a copper/arsenate resistance locus. GSU10-3 is the first nonclinical KPC-2-producing environmental Enterobacteriaceae isolate from Japan for which the whole genome has been sequenced. IMPORTANCE We isolated and determined the complete genome sequence of a KPC-2-producing K. pneumoniae strain from a sampling site in Tokyo Bay, Japan, near a wastewater treatment plant (WWTP). In Japan, the KPC type has been very rarely detected, while IMP is the most predominant type of carbapenemase in clinical carbapenemase-producing Enterobacteriaceae (CPE) isolates. Although laboratory testing thus far suggested that Japan may be virtually free of KPC-producing Enterobacteriaceae , we have detected it from effluent from a WWTP. Antimicrobial resistance (AMR) monitoring of WWTP effluent may contribute to the early detection of future AMR bacterial dissemination in clinical settings and communities; indeed, it will help illuminate the whole picture in which environmental contamination through WWTP effluent plays a part., (Copyright © 2018 Sekizuka et al.)

The ATP2B1 gene is associated with hypertension. We previously reported that systemic heterozygous ATP2B1-null (ATP2B1 +/- ) mice exhibited hypertension due to impaired endothelial nitric oxide synthase (eNOS) activity and decreased nitric oxide (NO) production. The ATP2B1 gene encodes plasma membrane calcium ATPase 1 (PMCA1), which has been thought to regulate only intracellular Ca 2+ concentration. However, recently, it has been suggested that ATP2B1 works not only at cellular levels, but also throughout the entire body, including in the calcium metabolism, using small intestine-specific ATP2B1 knockout mice. To clarify the roles of ATP2B1 in the entire body and the effects of ATP2B1 on blood pressure, we examined the alterations of calcium related factors in ATP2B1 +/- mice. ATP2B1 +/- mice exhibited hypocalcemia. The expression of ATP2B1 in the kidney and small intestine decreased, and hypercalciuria was confirmed in ATP2B1 +/- mice. The intact-PTH levels were lower, and bone mineral density was increased in these mice. These results suggest that hypocalcemia is mainly a result of inhibited bone resorption without compensation by PTH secretion in the case of ATP2B1 knockout. Moreover, NO production may be affected by reduced PTH secretion, which may cause the increase in vascular contractility in these mice. The ATP2B1 gene is important for not only intra-cellular calcium regulation but also for calcium homeostasis and blood pressure control.

Background: The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments., Methods: This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension., Results: Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = -0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p < 0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022)., Conclusion: Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.

ATP2B1 is a gene associated with hypertension. We reported previously that mice lacking ATP2B1 in vascular smooth muscle cells (VSMC ATP2B1 KO mice) exhibited high blood pressure and increased intracellular calcium concentration. The present study was designed to investigate whether lack of the ATP2B1 gene causes a higher response to calcium channel blockers (CCBs) than to other types of anti-hypertensive drugs. Both VSMC ATP2B1 KO and control mice were administered anti-hypertensive drugs while monitoring blood pressure shifts. We also examined the association of nitric oxide synthase (NOS) activity in those mice to investigate whether another mechanism of hypertension existed. VSMC ATP2B1 KO mice exhibited significantly greater anti-hypertensive effects with a single injection of nicardipine, but the effects of an angiotensin II receptor blocker (ARB), an α-blocker and amlodipine on blood pressure were all similar to control mice. However, long-term treatment with amlodipine, but not an ARB, significantly decreased the blood pressure of KO mice compared with control mice. Both mRNA and protein expression levels of the L-type calcium channel were significantly upregulated in KO VSMCs. There were no alterations in neural NOS protein expression of VSMCs or in urinary NO production between the two groups. VSMC ATP2B1 KO mice had a higher response to CCBs for blood pressure-lowering effects than other anti-hypertensive drugs. These results mean that increased intracellular calcium concentration in VSMCs due to lack of ATP2B1 and subsequent activation of L-type calcium channels mainly affects blood pressure and suggests increased susceptibility to CCBs in this type of hypertension.

Background: Tolvaptan, a vasopressin V 2 receptor blocker, has a diuretic effect for patients with heart failure. However, there were a few data concerning the effects of tolvaptan in patients with chronic kidney disease (CKD)., Methods: We retrospectively analyzed 21 patients with chronic heart failure and CKD. Tolvaptan was co-administered with other diuretics in-use, every day. We compared clinical parameters before and after the treatments with tolvaptan. Furthermore, we examined the correlations between baseline data and the change of body weight., Results: Tolvaptan decreased the body weight and increased the urine volume (p = 0.001). The urine osmolality significantly decreased throughout the study period. Urinary Na/Cr ratio and FENa changed significantly after 4 h, and more remarkable after 8 h (p = 0.003, both). Serum creatinine increased slightly after 1 week of treatment (p = 0.012). The alteration of body weight within the study period correlated negatively with the baseline urine osmolality (r = -0.479, p = 0.038), the baseline urine volume (r = -0.48, p = 0.028), and the baseline inferior vena cava diameter (IVCD) (r = -0.622, p = 0.017). Hyponatremia was improved to the normal value, and the augmentations of the sodium concentration were negatively associated with the basal sodium levels (p = 0.01, r = -0.546)., Conclusions: Tolvaptan is effective in increasing diuresis and improved hyponatremia, even in patients with CKD. The baseline urine osmolality, urine volume, and IVCD may be useful predictors for diuretic effects of tolvaptan.

Plasma membrane calcium pump isoform 1 (PMCA1) is encoded by ATPase plasma membrane Ca 2+ transporting 1 ( ATP2B1 ), the most likely candidate gene responsible for hypertension. Although PMCA1 is highly expressed in the kidney, little is known about regulation of its renal expression in various pathological conditions in vivo. Our study was designed to elucidate regulation of renal PMCA1 expression in mice. We employed three mouse models for kidney disease. These were the unilateral ureteral obstruction (UUO), the remnant kidney using 5/6 nephrectomy, and chronic angiotensin II administration models. Mice were assessed for systolic blood pressure and renal injury in accordance with the damage induced in the specific model. Kidney PMCA1 mRNA levels were measured in all mice. The UUO model showed renal fibrosis but no changes in blood pressure or renal PMCA1 mRNA expression. Similarly, the 5/6 nephrectomy model exhibited declined renal function without changes in blood pressure or renal PMCA1 mRNA expression. In contrast, chronic angiotensin II administration increased albuminuria and blood pressure as well as significantly increasing renal PMCA1 mRNA and protein expression. These results suggest that renal PMCA1 has a role as one of the molecules involved in angiotensin II-induced hypertension and kidney injury., (© 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Aim: Patients with orthostatic hypotension (OH) have high arterial stiffness. Patients with diabetes mellitus (DM) often have cardiac autonomic neuropathy that leads to OH; however, whether OH is an indicator of arterial stiffness progression is unclear. We aimed to investigate whether the cardio-ankle vascular index (CAVI) varies between DM patients with and without OH using the sit-to-stand test (STST)., Methods: One hundred and fifty-nine patients with DM underwent CAVI assessment and blood pressure (BP) and heart rate change evaluation during the STST. OH was defined as a decline in systolic BP (SBP) and/or diastolic BP of at least 20 mmHg or 10 mmHg, respectively, in the initial and late upright positions compared with that in the sitting position., Results: OH was diagnosed in 42 patients (26.4%). DM patients with OH had significantly higher CAVI (9.36±1.15 versus 8.89±1.18, p=0.026) than those without OH. CAVI was significantly inversely correlated with systolic and diastolic BP changes (R=－0.347, p＜0.001 and R=－0.314, p＜0.001, respectively) in the initial upright position. Multivariate regression analysis revealed that age, SBP changes, and low frequency component in the initial upright position were independent determinants of CAVI., Conclusion: Patients with DM having large BP drops occurring when moving from sitting to standing have high arterial stiffness. A significant BP drop during the STST necessitates careful evaluation of advanced arterial stiffness in patient with DM., Competing Interests: Conflict of Interests The authors declare that they have no conflicts of interest.

Epithelial sodium channels (ENaCs) play critical roles in the maintenance of fluid and electrolyte homeostasis, and their genetic abnormalities cause one type of hereditary salt-sensitive hypertension, Liddle syndrome. As we reported previously, both human and rodent Nedd4L/Nedd4-2 showed molecular diversity, with and without a C2 domain in their N-terminal. Nedd4L/Nedd4-2 isoforms with a C2 domain are hypothesized to be related closely to ubiquitination of ENaCs. We generated Nedd4-2 C2 domain knockout mice. We demonstrate here that loss of Nedd4-2 C2 isoform causes salt-sensitive hypertension under conditions of a high dietary salt intake in vivo. The knockout mice had reduced urinary sodium excretion, osmotic pressure and increased water intake and urine volume with marked dilatation of cortical tubules while receiving a high salt diet. To the contrary, there was no difference in metabolic data between wild-type and knockout mice receiving a normal control diet. In the absence of Nedd4-2 C2 domain, a high salt intake accelerated ENaC expression. Coimmunoprecipitation studies revealed suppressed ubiquitination for ENaC with a high salt intake. Taken together, our findings demonstrate that during a high oral salt intake the Nedd4-2 C2 protein plays a pivotal role in maintaining adaptive salt handling in the kidney.

Immunoglobulin A nephropathy (IgAN) is the most common form of primary glomerulonephritis in many parts of the world. Although previous genome-wide association studies (GWAS) identified the major susceptibility loci for IgAN, the causal genes currently remain unknown. We performed a GWAS using 23 465 microsatellite (MS) markers to identify genes related to IgAN in a Japanese population. A pooled sample analysis was conducted in three-stage screenings of three independent case-control populations, and after the final step of individual typing, 11 markers survived. Of these, we focused on two regions on 6p21 and 12q21 because they (i) showed the strongest relationship with IgAN, and (ii) appeared to be highly relevant to IgAN in view of several previous studies. These regions contained the HLA, TSPAN8 and PTPRR genes. This study on GWAS, using >20 000 MS markers, provides a new approach regarding susceptible genes for IgAN for investigators seeking new tools for the prevention and treatment of IgAN.

Background: Cyclosporine and prednisolone combination therapy has been used in the treatment of minimal change nephrotic syndrome (MCNS). However, few studies have evaluated the efficacy of cyclosporine combined with intravenous methylprednisolone pulse therapy (MPT) as a first-line treatment for new-onset MCNS. We conducted a retrospective clinical study to evaluate the efficacy and safety of cyclosporine combined with MPT and oral prednisolone for new-onset MCNS in adults., Methods: Forty-six adult patients with biopsy-proven MCNS were analyzed retrospectively. This study included three groups. Group 1 (n = 17) was treated with intravenous MPT (0.5 or 1.0 g/day for 3 days) followed by oral cyclosporine (2-3 mg/kg/day) and prednisolone (30 mg/day). Group 2 (n = 15) was treated with intravenous MPT followed by oral prednisolone (0.4-0.8 mg/kg/day). Group 3 (n = 14) was treated with oral prednisolone (0.6-1.0 mg/kg/day) alone., Results: The length of hospital stay was the shortest in Group 1 (P < 0.001). The mean duration to achieve <20 mg/day of prednisolone was also the shortest in Group 1 (P < 0.05). Complete remission rates were 100 % in Group 1, 85.7 % in Group 2, and 69.2 % in Group 3 during the 9-month follow-up (P = 0.073). The rate of adverse effects caused by prednisolone was less in Group 1 (P < 0.05). Multivariate analysis revealed that the independent determinants of durations of remission were the selectivity index (P = 0.004), eGFR (P = 0.001) and the use of cyclosporine (P = 0.045)., Conclusions: Combination therapy with cyclosporine may be a beneficial treatment option for new-onset MCNS in adults because of its clinical efficacy and safety.