67 research outputs found

    A pyrene-armed hexahomotrioxacalix[3]arene as a multi-sensor via synergistic and demetallation effects

    Get PDF
    A new pyrene-armed hexahomotrioxacalix[3]arene L has been synthesized, which exhibits a pronounced fluorescence enhancement response toward Cu²⁺ ions via a Zn²⁺ or Cd²⁺ triggered synergistic effect. Additionally, the L·Cu²⁺+ complex can subsequently serve as a sensor for F⁻ via anion-induced demetallation. The fluorescence responses by the input of Cu²⁺, Zn²⁺/Cd²⁺ and F⁻ can be constructed as a combinational logic gate which mimics a set of molecular traffic signals

    Ultrasensitive determination of pyrroloquinoline quinone in human plasma by HPLC with chemiluminescence detection using the redox cycle of quinone

    Get PDF
    A fast, accurate, and ultrasensitive high-performance liquid chromatography method with chemiluminescence detection (HPLC-CL) was optimized and validated for the determination of pyrroloquinoline quinone (PQQ) concentration in human plasma following solid-phase extraction (SPE). This method is based on the redox cycle of the reaction between PQQ and dithiothreitol, which generates reactive oxygen species that can be detected using luminol as a CL probe. The isocratic HPLC system comprised an ODS column and 4.0 mM tetra-n-butylammonium bromide in Tris-HNO3 buffer (pH 8.8; 50 mM)-acetonitrile (7:3, v/v) as mobile phase. A novel, rapid, and simple SPE method was also developed providing excellent %recovery (?95.2%) for PQQ from human plasma samples. The proposed method was linear over the range of 4.0?400 nmol/L plasma of PQQ with a lower detection limit (S/N=3) of 1.08 nmol/L plasma (0.27 nM). The method was successfully implemented to determine PQQ concentration in the plasma of healthy individuals after administration of PQQ supplements

    Further expansion of distributional range of an introduced spider Badumna insignis in the eastern part of Tottori Prefecture (Results of the surveys in 2017).

    Get PDF
    2017 年の夏から秋にかけて鳥取県の東部を中心として外来種のクロガケジグモ(クモ目ウシオグモ科)の分布範囲を調査した。これまで本種が未確認の鳥取県西部でも数地点(境港市,米子市,大山町,日南町)調べたが,今回も生息は確認できなかった。鳥取県東部では,既知生息範囲から遠く離れた若桜町内や岩美町内でもそれぞれ1 地点で生息を確認した。離れているこれら2 地点を除いたほぼ連続的と考えられる鳥取市周辺の本種の今回の生息確認範囲は2014 年における生息確認範囲よりも広く,西は国道9 号線沿いの白兎海岸,南は国道53 号沿いに河原町布袋,国道29 号線沿いに八頭町下坂まで伸びていた(西へは約2.5 km,南には約6 km 拡大)。いっぽう,交通量の少ない鳥取市南西側の県道沿いには新規の拡大はみられず,本種の分布域の拡大に人の移動や物流が関係していることを示唆した。本種が生息する地点では在来種のクモの個体数が減少していた。クロガケジグモの個体数の多さが目立つのは,早くから本種の生息域となっている湖山町周辺が含まれる千代川以西・国体道路以北の鳥取市街地であった。 We surveyed distribution of an introduced spider Badumna insignis (Araneae: Desidae) in Tottori Prefecture in 2017. There were no sites where B. insignis was found in the western part of Tottori Prefecture, as reported in the former surveys. On the other hand, we found the species in Iwami-cho and Wakasa-cho, where B. insignis had not been found. Continuous range of distribution of the species in Tottori City expanded ca. 2.5 km toward west along the national route 9, and ca. 6 km toward south, along major national routes (Routes 29 and 53). On the other hand, there was no expansion of the species toward southwestern part of the city where only prefectural roads with a few traffic extend. These facts suggest that human movements and logistics help expansion of the spider. The individual number of native spiders at sites where B. insignis inhabits was much fewer than that at sites without B. insignis

    Strong Evidence of a Combination Polymorphism of the Tyrosine Kinase 2 Gene and the Signal Transducer and Activator of Transcription 3 Gene as a DNA-Based Biomarker for Susceptibility to Crohn’s Disease in the Japanese Population

    Get PDF
    OBJECTIVE: An association between susceptibility to inflammatory bowel disease (IBD) and polymorphisms of both the tyrosine kinase 2 gene (TYK2) and the signal transducer and activator of transcription 3 gene (STAT3) was examined in a Japanese population in order to identify the genetic determinants of IBD. METHODS: The study subjects comprised 112 patients with ulcerative colitis, 83 patients with Crohn's disease (CD), and 200 healthy control subjects. Seven tag single-nucleotide polymorphisms (SNPs) in TYK2 and STAT3 were detected by PCR-restriction fragment length polymorphism. RESULTS: The frequencies of a C allele and its homozygous C/C genotype at rs2293152 SNP in STAT3 in CD patients were significantly higher than those in control subjects (P = 0.007 and P = 0.001, respectively). Furthermore, out of four haplotypes composed of the two tag SNPs (rs280519 and rs2304256) in TYK2, the frequencies of a Hap 1 haplotype and its homozygous Hap 1/Hap1 diplotype were significantly higher in CD patients in comparison to those in control subjects (P = 0.023 and P = 0.024, respectively). In addition, the presence of both the C/C genotype at rs2293152 SNP in STAT3 and the Hap 1/Hap 1 diplotype of TYK2 independently contributes to the pathogenesis of CD and significantly increases the odds ratio to 7.486 for CD (P = 0.0008). CONCLUSION: TYK2 and STAT3 are genetic determinants of CD in the Japanese population. This combination polymorphism may be useful as a new genetic biomarker for the identification of high-risk individuals susceptible to CD

    Hydrogen in Drinking Water Reduces Dopaminergic Neuronal Loss in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine Mouse Model of Parkinson's Disease

    Get PDF
    It has been shown that molecular hydrogen (H2) acts as a therapeutic antioxidant and suppresses brain injury by buffering the effects of oxidative stress. Chronic oxidative stress causes neurodegenerative diseases such as Parkinson's disease (PD). Here, we show that drinking H2-containing water significantly reduced the loss of dopaminergic neurons in PD model mice using both acute and chronic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The concentration-dependency of H2 showed that H2 as low as 0.08 ppm had almost the same effect as saturated H2 water (1.5 ppm). MPTP-induced accumulation of cellular 8-oxoguanine (8-oxoG), a marker of DNA damage, and 4-hydroxynonenal (4-HNE), a marker of lipid peroxidation were significantly decreased in the nigro-striatal dopaminergic pathway in mice drinking H2-containing water, whereas production of superoxide (O2•−) detected by intravascular injection of dihydroethidium (DHE) was not reduced significantly. Our results indicated that low concentration of H2 in drinking water can reduce oxidative stress in the brain. Thus, drinking H2-containing water may be useful in daily life to prevent or minimize the risk of life style-related oxidative stress and neurodegeneration

    The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome.

    Get PDF
    X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X's gene content, gene expression, and evolution

    Identification of muscle synergies associated with gait transition in humans

    Get PDF
    There is no theoretical or empirical evidence to suggest how the central nervous system (CNS) controls a variety of muscles associated with gait transition between walking and running. Here, we examined the motor control during a gait transition based on muscle synergies, which modularly organize functionally similar muscles. To this end, the subjects walked or ran on a treadmill and performed a gait transition spontaneously as the treadmill speed increased or decreased (a changing speed condition) or voluntarily following an experimenter's instruction at constant treadmill speed (a constant speed condition). Surface electromyograms (EMGs) were recorded from 11 lower limb muscles bilaterally. We then extracted the muscle weightings of synergies and their activation coefficients from the EMG data using non-negative matrix factorization. As a result, the gait transition was controlled by approximately 9 muscle synergies, which were common during a walking and running, and their activation profiles were changed before and after a gait transition. Near a gait transition, the peak activation phases of the synergies, which were composed of plantar flexor muscles, were shifted to an earlier phase at the walk-to- run transition, and vice versa. The shifts were gradual in the changing speed condition, but an abrupt change was observed in the constant speed condition. These results suggest that the CNS low-dimensionally regulate the activation profiles of the specific synergies based on afferent information (spontaneous gait transition) or by changing only the descending neural input to the muscle synergies (voluntary gait transition) to achieve a gait transition
    corecore