The opportunities for exposure to radiofrequency electromagnetic fields (RF-EMF) among children are increasing. Children's exposure to RF-EMF in Japan was recorded using a personal exposure meter (ExpoM-RF), and factors associated with the exposure examined. A total of 101 children, aged 10-15 years old, participated in the prospective birth cohort "Hokkaido study".
View Article and Find Full Text PDFSerum fatty acids (FAs) exist in the four lipid fractions of triglycerides (TGs), phospholipids (PLs), cholesteryl esters (CEs) and free fatty acids (FFAs). Total fatty acids (TFAs) indicate the sum of FAs in them. In this study, four statistical analysis methods, which are independent component analysis (ICA), factor analysis, common principal component analysis (CPCA) and principal component analysis (PCA), were conducted to uncover food sources of FAs among the four lipid fractions (CE, FFA, and TG + PL).
View Article and Find Full Text PDFWith increasing use of mobile phones, exposure to radiofrequency electromagnetic field (RF-EMF) in the high-frequency band associated with mobile phones has become a public concern, with potentially adverse effects on cognitive function in children and adolescents. However, findings regarding the relation of RF-EMF and cognitive function in children and adolescents have been inconsistent due to a number of study design-related factors, such as types of exposure and outcome measures, age of participants, and the era of study conduction. The present literature review focused on these possible factors that could explain this inconsistency.
View Article and Find Full Text PDFCholesteryl ester (CE) is an ester of cholesterol and fatty acid (FA). Plasma CE reflects complicated metabolisms of cholesterol, phospholipids, lipoproteins, and dietary FAs. An informatics approach could be useful for analysis of the CE species.
View Article and Find Full Text PDF25-Hydroxyvitamin D (25(OH)D) as the metabolite of vitamin D, is connected with various of diseases, and important to people with limited sunshine. Thus, the investigation of serum 25-hydroxyvitamin D and its variation in these people is necessary. In this study, a simple, precise, and accurate method for serum 25(OH)D determination by LC/MS/MS was developed.
View Article and Find Full Text PDFIn this paper, we compare two radiation effect models: the average surviving fraction (ASF) model and the integral biologically effective dose (IBED) model for deriving the optimal irradiation scheme and show the superiority of ASF. Minimizing the effect on an organ at risk (OAR) is important in radiotherapy. The biologically effective dose (BED) model is widely used to estimate the effect on the tumor or on the OAR, for a fixed value of dose.
View Article and Find Full Text PDFWe studied change in the plasma total, esterified and non-esterified capric acid (FA10:0) and its effect on longer fatty acid concentrations during the short-term oral administration of synthetic tricaprin in dogs. We administered 150 and 1500 mg tricaprin/kg body weight per day orally to dogs for 7 consecutive days. Blood samples were collected at 0, 0.
View Article and Find Full Text PDFMotivation: DNA methylation is an important epigenetic modification related to a variety of diseases including cancers. We focus on the methylation data from Illumina's Infinium HumanMethylation450 BeadChip. One of the key issues of methylation analysis is to detect the differential methylation sites between case and control groups.
View Article and Find Full Text PDFPurpose: Radiotherapy of solid tumors has been performed with various fractionation regimens such as multi- and hypofractionations. However, the ability to optimize the fractionation regimen considering the physical dose distribution remains insufficient. This study aims to optimize the fractionation regimen, in which the authors propose a graphical method for selecting the optimal number of fractions (n) and dose per fraction (d) based on dose-volume histograms for tumor and normal tissues of organs around the tumor.
View Article and Find Full Text PDFPurpose: The authors propose a graphical representation of the relation between the effect on the tumor and the damage effect on an organ at risk (OAR) against the irradiation dose, as an aid for choosing an appropriate fractionation regimen.
Methods: The graphical relation is depicted by the radiation effect on the tumor E(1) versus that on an OAR E(0). By observing the features of the E(1) vs E(0) relation curve, i.
Purpose: Hypofractionated irradiation is often used in precise radiotherapy instead of conventional multifractionated irradiation. We propose a novel mathematical method for selecting a hypofractionated or multifractionated irradiation regimen based on physical dose distribution adding to biologic consideration.
Methods And Materials: The linear-quadratic model was used for the radiation effects on tumor and normal tissues, especially organs at risk (OARs).
We have previously reported DNA triplexes containing the unnatural base triad G-PPI·C3, in which PPI is an indole-fused cytosine derivative incorporated into DNA duplexes and C3 is an abasic site in triplex-forming oligonucleotides (TFOs) introduced by a propylene linker. In this study, we developed a new unnatural base triad A-ψ·C(R1) where ψ and C(R1) are base moieties 2'-deoxypseudouridine and 5-substituted deoxycytidine, respectively. We examined several electron-withdrawing substituents for R1 and found that 5-bromocytosine (C(Br)) could selectively recognize ψ.
View Article and Find Full Text PDFA series of oligodeoxynucleotides labeled by a pyrimidopyrimidoindole deoxynucleoside (1a: dC(PPI)) and its derivatives 2a and 3a substituted with electron-donating and -withdrawing groups, respectively, were synthesized according to the phosphoramidite approach. The photophysical properties and quenching efficiencies of oligonucleotides incorporating dC(PPI) derivatives were studied in detail. The thermal denaturation experiments and molecular dynamics simulation of DNA duplexes incorporating dC(PPI) suggested that a modified base of dC(PPI) could form base pairs with guanine and adenine in canonical Watson-Crick and reverse-wobble geometries, respectively.
View Article and Find Full Text PDFNew nucleotide pairs applicable to formation of DNA triplexes were developed. We designed oligonucleotides incorporating 5-aryl deoxycytidine derivatives (dC5Ars) and cyclic deoxycytidine derivatives, dCPPP and dCPPI, having an expanded aromatic area, as the second strand. As pairing partners, two types of abasic residues (C3: propylene linker, phi: abasic base) were chosen.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
March 2008
A new fluorescent deoxycytidine analog, 10-(2-deoxy-beta -D-ribofuranosyl)-pyrimido[4',5' :4,5]-pyrimido[1,6-a]indole-6,9(7H)-dione (dC(PPI)) was synthesized. Its fluorescent properties were studied in detail. It was found that this fluorescent nucleoside dC(PPI) could be used as a fluorescent label for DNA probes with minimal disturbance of their overall structure.
View Article and Find Full Text PDFNucleic Acids Symp Ser (Oxf)
April 2008
We synthesized 2'-O-methyl RNAs having bulky substituents at the 5' and 3'-terminal bases and examined their hybridization properties. The hybridization of the modified RNAs to the targets RNA was studied varying the chain length of the targets. As the result, it was proved that the duplex of the modified 2'-O-methyl RNAs and the long targets were destabilized in comparison with that of the modified 2'-O-methyl RNAs and the short targets.
View Article and Find Full Text PDFIn this paper, we reported our attempt to use a 5arylcytosine (dC(ar)) and the abasic site () as an artificial base pair for DNA triplex. The idea was confirmed by the molecular modeling studied in which the aromatic group of (ph) which protrudes in the major groove was buried into the cleft formed by the residue in the TFO. We synthesized three kinds of dC(ar) and the oligonucleotides incorporating them.
View Article and Find Full Text PDF10-(2-Deoxy-beta-D-ribofuranosyl)pyrimido[4',5':4,5]pyrimido[1,6-a]indole-6,9(7H)-dione (dCPPI) and its derivatives were synthesized via the Suzuki-Miyaura coupling reaction of 5-iododeoxycytidine with 5-substituted N-Boc-indole-2-borates and characterized by UV-vis and fluorescence spectroscopy. The new fluorescent nucleosides showed rather large Stokes shifts (116-139 nm) in an aqueous buffer. The fluorescent intensities were dependent on the nature of the substituents on the indole rings.
View Article and Find Full Text PDFNew bi- and tricyclic deoxycytidine derivatives (dChpd, dCmpp, dCtpp, dCppp) were synthesized as analogues of a fluorescent nucleoside, dChpp, previously reported. The carbamoyl group of dChpd and the 5-position of the cytosine ring are bridged via an ethylene linker so that the modified group forms a nonplanar structure with the cytosine ring. The fluorescent study of dChpd indicated that the coplanar structure between the carbamoyl group and the cytosine ring is of importance.
View Article and Find Full Text PDFWe report here the synthesis and spectroscopic characterization of a new fluorescent pyrimidopyrimidoindole nucleoside derivative (dC(PPI)) modified at the cytosine base. The photophysical properties of dC(PPI) were examined by fluorescent spectroscopy and quantum chemical calculations. It was found that dC(PPI)-labeled oligonucleotides gave almost the same thermal stability as that of the corresponding unmodified sequences.
View Article and Find Full Text PDFNucleic Acids Symp Ser (Oxf)
July 2007
Ferrocene-polyamides having not only sequence discrimination ability but also a redox mediator were synthesized. The affinity and selectivity of these compounds for a DNA duplex having a cognate GCG sequence were investigated by CD spectroscopy. Furthermore, the binding of the ferrocene-polyamides to DNA duplexes immobilized to a gold electrode was detected by cyclic voltammetry (CV) experiments.
View Article and Find Full Text PDF[reaction: see text] The synthesis and properties of new conjugate molecules, Fc-PIA, composed of ferrocene (Fc) and pyrrole-imidazole polyamides (PIA) are reported. As a PIA sequence, we chose Im-Py-Im/Py-Im-Py considering its future application to the SNPs detection of genes having a GCG/CGC sequence. Two types of Fc-containing linkers, i.
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