Global analysis of single nucleotide polymorphisms in the exons of human deoxyribonuclease I-like 1 and 2 genes

Several SNPs in the deoxyribonuclease I-like 1 (DNase 1L1) and DNase 1L2 were investigated. In the present study, the genotype distributions of three synonymous SNPs (V59V, rs1050095; P67P, rs1130929; A277A, rs17849495) in the DNase 1L1 gene and four non-synonymous SNPs, V122I (rs34952165), Q170H (rs6643670), and D227A (rs5987256) in the DNase 1L1 gene, as well as D197A (rs62621282) in the DNase 1L2 gene were investigated in 13 populations. In all the populations, no variation was found in four SNPs (V59V, Q170H, D227A, and A277A) in DNASE1L1 or in D197A in DNASE1L2. As for V122I, only the German population showed a low degree of polymorphism. The SNP V122I in DNASE1L1 was monoallelic for the G-allele in all of the Asian and African populations examined, with no polymorphism being evident. Since the A-allele in SNP V122I was distributed in only the Caucasian populations, not in the other ethnic groups, it was confirmed that the A-allele in SNP V122I was Caucasian-specific. On the other hand, only P67P in DNASE1L1 was polymorphic among three synonymous SNPs. The effect of nucleotide substitution corresponding to polymorphic SNP P67P on DNase 1L1 activity was examined: the corresponding nucleotide substitution in polymorphic SNP P67P has little effect on the DNase activity.     

RP–HPLC–ESI–MS characterization of novel peptide fragments related to rat parotid secretory protein in parasympathetic induced saliva

Two peptides (MW 1211.7 and 928.5 Da) were detected by RP–HPLC–ESI–MS analysis of parotid saliva secreted upon continuous parasympathetic stimulation. The peptide with the higher mass (PSPFr‐A) corresponded to the N‐terminal dodecapeptide (Fragment 1–12) of rat parotid secretory protein (PSP), while the peptide with the lower mass (PSPFr‐B) corresponded to the 4–12 fragment of the same protein. During stimulation, the PSPFr‐A secretion increased, while the PSPFr‐B secretion decreased (HPLC–ESI–MS). In the presence of cycloheximide, PSPFr‐A was not demonstrated, while the PSPFr‐B secretion decreased. In the presence of aprotinin, the PSPFr‐B secretion was almost abolished, while the PSPFr‐A secretion increased to higher levels than those observed in the absence of the inhibitor. In vitro perfusion, with artificial solution, of stimulated rat parotid glands excluded that the fragments were derived from the circulation. Neither peptide occurred in enriched granule preparations from unstimulated glands. The results suggest that at least two pathways – granular and vesicular – are responsible for the generation of the two peptides. PSPFr‐A is the first cleavage product in both pathways. PRPFr‐B is probably generated from granular PSPFr‐A only and, at the end of the granule mediated pathway, by the action of an enzyme of the serine protease class.     

Monocular viewing prolongs reversal interval of perceptual rival figure

The authors examined whether the perceptual reversal rate changes under monocular versus binocular viewing conditions. Our results suggest that the perceptual reversal interval increases during monocular viewing. The ratio of the reversal rate (1/interval) for the two viewing conditions (binocular/monocular) was 1.28 over a wide range of pattern luminance levels. The quoted ratio was 1.40 when the luminance was high. Such a ratio parallels the value of a well-known binocular summation index $(\sqrt 2 )$ , which was derived from the signal detection theory. The binocular summation index shows that the strength of an input signal is enhanced by binocular viewing. However, how the binocular summation shortens the perceptual reversal interval is unclear. This issue can be resolved if the perceptual reversal is derived by integrating the strength of an unconscious image signal. Thus, we discussed the mechanism of perceptual switch by associating two classical, well-studied phenomena, binocular summation and perceptual switch.     

Compensation effect of Mg-doped a- and c-plane GaN films grown by metalorganic vapor phase epitaxy

The electrical and optical properties of Mg-doped a- and c-plane GaN films grown by metalorganic vapor phase epitaxy were systematically investigated. The photoluminescence spectra of Mg-doped a- and c-plane GaN films exhibit strong emissions related to deep donors when Mg doping concentrations are above 1×10²⁰ cm⁻³ and 5×10¹⁹ cm⁻³, respectively. The electrical properties also indicate the existence of compensating donors because the hole concentration decreases at such high Mg doping concentrations. In addition, we estimated the N_D/N_A compensation ratio of a- and c-plane GaN by variable-temperature Hall effect measurement. The obtained results indicate that the compensation effect of the Mg-doped a-plane GaN films is lower than that of the Mg-doped c-plane GaN films.     

Electrochemical and DNA-binding properties of dipyridophenazine complexes of osmium(II)

A transition metal complex as an electrochemical probe of a DNA sensor must have an applicable redox potential, high binding affinity and chemical stability. Some complexes with the dipyrido[3,2-a:2′,3′-c]phenazine (DPPZ) ligand have been reported to have high binding affinity for DNA. However, it was difficult to detect the targeted DNA electrochemically using these complexes because of the relatively high redox potential. In this work, a combination of bipyridine ligands with functional groups (---NH₂, ---CH₃ and ---COOH) and the DPPZ ligand were studied. The introduction of electron-donating groups was effective for controlling the redox potential of the DPPZ-type osmium complex. The [Os(DA-bpy)₂DPPZ]²⁺ complex (DA-bpy; 4,4′-diamino-2,2′-bipyridine) had a lower half-wave potential (E_1/2) of 147 mV (vs. Ag AgCl) and higher binding affinity with DNA {binding constant, K=3.1×10⁷ M⁻¹ in 10 mmol dm⁻³ Tris–HCl buffer with 50 mmol dm⁻³ NaCl (pH 7.76)} than those of other complexes. With the single stranded DNA (ssDNA) modified gold electrode, the hybridization signal (ΔI) of the [Os(DA-bpy)₂DPPZ]²⁺ complex was linear in the concentration range of 1.0 pg ml⁻¹–0.12 μg ml⁻¹ for the targeted DNA with a regression coefficient of 0.999. The detection limit was 0.1 pg ml⁻¹.     

Photo-Deformation of Syndiotactic Polystyrene Gels

We report a usual and novel phenomenon that an excitation light beam of a spectrofluorometer produced a black mark in gels of syndiotactic polystyrene (SPS). This mark whose shape is identical with that of an excitation light beam was found to appear in SPS/chloroform gel just after only irradiation at 260 nm for 5 to 10 min. The heating of the gel with the mark at 80°C diminished the mark and recovered uniformly the gel to be as it had been before irradiation. We discuss what the black mark is and why it is produced by light irradiation.     

d-Allulose Ameliorates Skeletal Muscle Insulin Resistance in High-Fat Diet-Fed Rats

Background: d-Allulose is a rare sugar with antiobesity and antidiabetic activities. However, its direct effect on insulin sensitivity and the underlying mechanism involved are unknown. Objective: This study aimed to investigate the effect of d-allulose on high-fat diet (HFD)-induced insulin resistance using the hyperinsulinemic–euglycemic (HE)-clamp method and intramuscular signaling analysis. Methods: Wistar rats were randomly divided into three dietary groups: chow diet, HFD with 5% cellulose (HFC), and HFD with 5% d-allulose (HFA). After four weeks of feeding, the insulin tolerance test (ITT), intraperitoneal glucose tolerance test (IPGTT), and HE-clamp study were performed. The levels of plasma leptin, adiponectin, and tumor necrosis factor (TNF)-α were measured using the enzyme-linked immunosorbent assay. We analyzed the levels of cell signaling pathway components in the skeletal muscle using Western blotting. Results: d-allulose alleviated the increase in HFD-induced body weight and visceral fat and reduced the area under the curve as per ITT and IPGTT. d-Allulose increased the glucose infusion rate in the two-step HE-clamp test. Consistently, the insulin-induced phosphorylation of serine 307 in the insulin receptor substrate-1 and Akt and expression of glucose transporter 4 (Glut-4) in the muscle were higher in the HFA group than HFC group. Furthermore, d-allulose decreased plasma TNF-α concentration and insulin-induced phosphorylation of stress-activated protein kinase/Jun N-terminal kinase in the muscle and inhibited adiponectin secretion in HFD-fed rats. Conclusions: d-allulose improved HFD-induced insulin resistance in Wistar rats. The reduction of the proinflammatory cytokine production, amelioration of adiponectin secretion, and increase in insulin signaling and Glut-4 expression in the muscle contributed to this effect.     

Enantioselective Ring Opening of Epoxides with 4-Methoxyphenol Catalyzed by Gallium Heterobimetallic Complexes: An Efficient Method for the Synthesis of Optically Active 1,2-Diol Monoethers

Useful chiral building blocks such as 1,2-diols can be obtained by the enantioselective ring opening of achiral epoxides with oxygen nucleophiles. The ring opening is carried out effectively (up to 94 % ee) with 4-methoxyphenol and catalytic amounts of gallium complexes. The novel complex GaSO 1 displays a particularly high catalytic activity.