Publications by authors named "Kotera N"

Coordinated motions are essential in the operation of molecular machines. This feature can be achieved by landscaping the energy surface along the movement coordinates. Herein, we present an approach of using a single stimulus to modify the free energy curve describing the threading and shuttling of a ring along a linear molecule.

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Isothermal hybridization of two DNA strands bearing three thymine-thymine (T:T) mismatches can be brought about in the presence of a stoichiometric amount of a bis-naphthalene macrocycle, 2,7-BisNP-NH. This process can be reverted by addition of a Cu salt due to formation of a dinuclear metal complex which does not bind to DNA. Subsequent sequestration of Cu releases the macrocycle and restores the hybridization state of DNA strands, thus allowing implementation of a fast fluorescent two-state DNA switch.

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Recently, several families of small-molecule ligands have been developed to selectively target DNA pairing defects, such as abasic sites and mismatched base pairs, with the aim to interfere with the DNA repair and the template function of the DNA. However, the affinity and selectivity (with respect to well-matched DNA) of these ligands has barely been evaluated in a systematic way. Herein, we report a comparative study of binding affinity and selectivity of a representative panel of 16 ligands targeting abasic sites and a T-T mismatch in DNA, using a fluorescence-monitored melting assay.

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Peritonitis remains an important cause of morbidity and mortality in peritoneal dialysis (PD) patients, but its incidence and the distribution of causative organisms vary widely between institutions and age groups. This study was performed to investigate the recent status and risk factors of PD-related peritonitis and to clarify differences between age groups. We retrospectively reviewed the medical records of 119 PD patients treated at our department between January 2002 and January 2013.

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Bis-naphthalene macrocycles, which bind with high affinity and selectivity to abasic sites in DNA, efficiently inhibit their cleavage by APE1 (IC50 = 55-60 nM in the kinetic assay with a model THF substrate). These results demonstrate that substrate masking by non-covalent abasic-site ligands is an efficient strategy for inhibition of APE1.

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Background: The relationship between dialysis amyloid (DA) deposition in the aortic valve (AV) and aortic stenosis (AS) is unknown.

Methods: This was a cross-sectional study. AV specimens of dialysis patients (median vintage: 8.

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Recombinant proteins bearing a tag are crucial tools for assessing protein location or function. Small tags such as Cys4 tag (tetracysteine; Cys-Cys-X-X-Cys-Cys) are less likely disrupt protein function in the living cell than green fluorescent protein. Herein we report the first example of the design and synthesis of a dual fluorescence and hyperpolarized (129)Xe NMR-based sensor of Cys4-tagged proteins.

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The present study compares health-related QOL between patients who practiced self-care activities comprising exercise and diet at home for at least 6 months (SA group; n = 84) after elective PCI and those who did not (NA group; n = 54). Health-related (HR) QOL was measured using the SF-36 questionnaire. Scores for two mental and three physical parameters of the HRQOL were increased in the SA, but not in the NA group.

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Mismatched (non-Watson-Crick) base pairs represent the most common type of DNA damage, as they are permanently formed in living cells due to erroneous insertion, deletion and misincorporation of bases. In vivo, they are readily recognised and repaired by the proteins of the DNA mismatch repair system, which identify the mismatch sites with high efficiency and fidelity. Notably, the last decades have witnessed the development of several chemically diverse families of small organic molecules and metal complexes that selectively bind to mismatched base pairs (and not to fully paired double-stranded DNA), much like the proteins of the mismatch repair system.

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An approach for sensitive magnetic resonance detection of metal cations is proposed. Combining the use of hyperpolarized (129)Xe NMR and of a cage-molecule functionalized by a ligand able to chelate different cations, we show that simultaneous detection of lead, zinc, and cadmium ions at nanomolar concentration is possible in short time, thanks to fast MRI sequences based on the HyperCEST scheme.

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The development of optimized xenon host systems is of crucial importance for the success of molecular imaging using hyperpolarized (129)Xe MRI. Cryptophane-111 is a promising candidate because of its encapsulation properties. The synthesis of cryptophane-111-based biosensors requires both water-solubilizing and chemically activatable groups.

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We describe the synthesis of a highly water-soluble cryptophane 1 that can be seen as a universal platform for the construction of (129)Xe magnetic resonance imaging (MRI)-based biosensors. Compound 1 is easily functionalized by Huisgen cycloaddition and exhibits excellent xenon-encapsulation properties. In addition, 1 is nontoxic at the concentrations typically used for hyperpolarized (129)Xe MRI.

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A 44-year-old man with a 17-year history of Crohn's disease (CD) was referred to our nephrology department on suspicion of drug-induced nephrotoxicity. Over the preceding 18 months, he had slowly progressive renal insufficiency with slight urinary abnormalities. His disease activity had been well controlled up to that point with 5-aminosalicylic acid and azathiopurine.

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Cryptophane-111 is one of the best candidates for (129)Xe MRI-based applications. Herein, we report the first metal-free and water-soluble cryptophane-111 core which involves an efficient and unusual post-synthetic sulfonation procedure.

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We report a case of a 47-year-old man with multicentric Castleman's disease (MCD) and progressive renal dysfunction due to mesangial proliferative glomerulonephritis, possibly from IgA nephropathy. At age 36 years, he was referred to a hematologist due to hypergammaglobulinemia. Because of systemic lymph node swelling, he underwent right cervical lymph node biopsy at age 41 years and MCD (plasma cell type)was diagnosed.

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The development of molecular imaging using hyperpolarized xenon MRI needs highly optimized biosensors. Cryptophane-111 and cryptophane-222 are promising candidates that show complementary encapsulation properties although they only differ by the length of the three alkane linkers joining two cyclotriphenolene units. Cryptophanes containing both methoxy and ethoxy linkers have never been synthesized.

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Background: Retinoids and active vitamin D(3) analogues regulate the proliferation and differentiation of keratinocytes and are effective in the treatment of psoriasis. Retinoids are known to be effective against acne vulgaris through comedolysis. However, the comedolytic effect of active vitamin D(3) analogues has not been reported.

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Hydroxyindole-O-methyltrasferase (HIOMT) plays an important role as the final enzyme in the synthesis of melatonin. In this study, the expression of the HIOMT gene in Japanese quail was investigated with respect to tissue distribution and the effects of light and vitamin A deficiency. HIOMT mRNA in the pineal gland and eye had a clear daily rhythm with peak values in daytime.

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