Mumefural and related HMF derivatives from Japanese apricot fruit juice concentrate show multiple inhibitory effects on pandemic influenza A (H1N1) virus

Fruit-juice concentrate of Japanese apricot (Prunus mume Sieb. et Zucc.) has been shown to be effective against influenza A infection in MDCK cells. In this study, we isolated five components from the fruit-juice concentrate of Japanese apricot, 5-(hydroxymethyl)-2-formylfuran (HMF), 1-[5-(2-formylfuryl)methyl]dihydrogen 2-hydroxypropane-1,2,3-tricarboxylate (mumefural, MF), 2-[5-(2-formylfuryl)methyl]dihydrogen 2-hydroxypropane-1,2,3-tricarboxylate (MF‘), 1-[5-(2-formylfuryl)methyl]hydrogen 1-hydroxyethane-1,2-dicarboxylate (MA1) and 2-[5-(2-formylfuryl)methyl]hydrogen 1-hydroxyethane-1,2-dicarboxylate (MA2), and investigated their inhibitory activities against the novel influenza A/Narita/1/2009 (H1N1) pandemic virus hemagglutinin and neuraminidase functions, which are essential for viral attachment and budding, respectively. An hemagglutination inhibition assay indicated that MF and MF‘ were effective at minimum hemagglutination concentrations of 3.1 and 6.3 mM, respectively. An inhibition study for sialidase activity of the neuraminidase spike showed that MF was the most active anti-sialidase compound with an IC₅₀ value of 0.21 ± 0.01 mM, followed by MA2 (IC₅₀, 0.71 ± 0.09 mM), MA1 (IC₅₀, 1.64 ± 0.31 mM) and MF‘(IC₅₀, 1.62 ± 0.22 mM). Furthermore, MF was shown to inhibit the growth of the pandemic virus in a dose-dependent manner (62 ± 3% inhibition at 5 mM). The results suggest that MF, a citric acid ester linked to HMF at the 1-position of the propane backbone, might be a lead compound for the development of anti-influenza A inhibitors.     

Synthesis of stable and soluble one-handed helical poly(substituted acetylene)s without chiral pendant groups via polymer reaction in membrane state

A soluble and stable one-handed helical conjugated polymer without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer having two hydroxyl groups followed by desubstitution of the chiral groups in a solid membrane state. The reason for the success was the polymer reaction was carried out in the membrane state. This is an alternative method to obtain such a unique chiral polymer which was obtained only by the helix-sense-selective polymerization (HSSP) we reported before. In addition the efficiency of the chiral induction was higher than that of the HSSP. It is interesting that the “Membrane state” acted like as if a protecting group.     

Modulation of the sensitive temperature range of fluorescent molecular thermometers based on thermoresponsive polymers

Fluorescent molecular thermometers based on polymers showing a temperature-induced phase transition and labeled with polarity-sensitive fluorescent benzofurazans are the most sensitive known. Here we show a simple and effective method for modulating the sensitive temperature ranges of fluorescent molecular thermometers based on such temperature-responsive polymers. 4-N-(2-acryloyloxyethyl)-N-methylamino-7-N,N-dimethylaminosulfonyl-2,1,3-benzoxadiazole was adopted as a polarity-sensitive fluorescent benzofurazan, and nine copolymers of two kinds of acrylamide derivative (N-n-propylacrylamide, N-isopropylacrylamide, and/or N-isopropylmethacrylamide) with a small amount of DBD-AE were obtained. The fluorescence intensities of these copolymers in aqueous solution sharply increased with increasing temperature over a small range (6-7 degrees C). In contrast, these fluorescent molecular thermometers differed from one another in the sensitive temperature range (between 20 and 49 degrees C). Moreover, the sensitive temperature ranges were well related to the acrylamide ratios in feed. In addition, the responses from these fluorescent molecular thermometers to the change in temperature were reversible and exactly repeatable during 10 cycles of heating and cooling (relative standard deviation of the fluorescence intensity, 0.44-1.0%).     

Contribution of amino acid substitutions at two different interior positions to the conformational stability of human lysozyme

To elucidate correlative relationships between structural changeand thermodynamic stability in proteins, a series of mutanthuman lysozymes modified at two buried positions (Ile56 andIle59) were examined. Their thermodynamic parameters of denaturationand crystal structures were studied by calorimetry and X-raycrystallography. The mutants at positions 56 and 59 exhibiteddifferent responses to a series of amino acid substitutions.The changes in stability due to substitutions showed a linearcorrelation with changes in hydrophobicity of substituted residues,having different slopes at each mutation site. However, thestability of each mutant was found to be represented by a uniqueequation involving physical properties calculated from mutantstructures. By fitting present and previous stability data formutant human lysozymes substituted at various positions to theequation, the magnitudes of the hydrophobicity of a carbon atomand the hydrophobicity of nitrogen and neutral oxygen atomswere found to be 0.178 and –0.013 kJ/mol.Ų, respectively.It was also found that the contribution of a hydrogen bond witha length of 3.0 Å to protein stability was 5.1 kJ/moland the entropy loss of newly introduction of a water moleculeswas 7.8 kJ/mol.     

Survey of pesticide residues in imported frozen vegetables and fruits (1989.4~2008.3)

A survey of pesticide residues in 595 imported frozen products on the Tokyo market from April 1989 to March 2008 was carried out. Forty three kinds of pesticides, including organophosphorus, organochlorine, carbamate, pyrethroid and others, were detected between levels of trace (below 0.01 ppm) and 4.6 ppm from 162 samples. Chlorpyrifos, cypermethrin and omethoate were frequently detected in green vegetables (komatsuna leaf and spinach), cypermethrin and methamidophos were detected in pods and seeds (green soybean and string pea), chlorpropham (CIPC) was detected in potato, and captan and carbaryl were detected in berries (blueberry, raspberry and strawberry). The hydrophilic pesticide methamidophos was detected in flesh of lychee. Residue levels of these pesticides were calculated as between less than 0.5% and 30% of their ADI values according to the daily intake of frozen products. Therefore, these frozen products should be safe when they were eaten in customary amounts.     

Inorganic-organic hybrid molecular architectures of cyanometalate host and organic guest systems: specific behavior of the guests

Molecular architectures built of inorganic cyanometalate building blocks provide variegated host structures with several organic guest molecules. The strategies to derive novel structures are presented briefly. The formation of a charge-transfer (CT) complex as the guest inside the cavity and the photochemistry of the CT complexes are discussed. The chemical pressure that the guest experiences inside the cavity is also discussed based on the vibrational spectroscopic results.     

Docosahexaenoic Acid and Eicosapentaenoic Acid Did not Alter <Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 Conjugated Linoleic Acid Incorporation into Mice Brain and Eye Lipids

trans 10,cis 12‐CLA has been reported to alter fatty acid composition in several non‐neurological tissues, but its effects are less known in neurological tissues. Therefore, the purpose of this study was to determine if CLA supplementation would alter brain and eye fatty acid composition and if those changes could be prevented by concomitant supplementation with docosahexaenoic acid (DHA; 22:6n3) or eicosapentaenoic acid (EPA; 20:5n3). Eight‐week‐old, pathogen‐free C57BL/6N female mice (n = 6/group) were fed either the control diet or diets containing 0.5% (w/w) t10,c12‐CLA in the presence or absence of either 1.5% DHA or 1.5% EPA for 8 weeks. CLA concentration was significantly (P < 0.05) greater in the eye but not in the brain lipids of the CLA group when compared with the control group. The sums of saturated, monounsaturated, polyunsaturated fatty acids, and n3:n6 ratio did not differ between these two groups for both tissues. The n3:n6 ratio and concentrations of 20:5n3 and 22:5n3 were significantly greater, and those of 20:4n6, 22:4n6, and 22:5n6 were lesser in the CLA + DHA and CLA + EPA groups than in the control and CLA groups for either tissue. DHA concentration was higher in the CLA + DHA group only but not in the CLA + EPA group when compared with the CLA group for both tissues. The dietary fatty acids generally induced similar changes in brain and eye fatty acid concentration and at the concentrations used both DHA and EPA fed individually with CLA were more potent than CLA alone in altering the tissue fatty acid concentration.     

Pretreatment of polyamide monofilament with hydrochloric acid improves sensitivity of three-dimensional microarray, Bio-Strand

A single-nucleotide-polymorphism-typing method using a novel three-dimensional DNA microarray, Bio-Strand, is promising because it is rapid, inexpensive and easily automated. It has been developed with the intent to overcome the drawbacks of conventional DNA microarrays, which use flat surfaces and impermeable materials such as glass slides; Bio-Strand as a novel DNA microarray, with its permeability, has a significantly improved stability compared with conventional DNA microarrays that use impermeable materials. In this study, we have developed a simple method of pretreating a polyamide monofilament to increase its surface area and to make it permeable, which makes Bio-Strand more sensitive and stable, allowing it to be adapted for clinical diagnostic applications. The fluorescence signal obtained with a nylon 6 monofilament pretreated under optimal conditions (hydrolysis by 5 M HCl/ethanol followed by washing with 50% ethanol and 100% ethanol) was significantly stronger than that obtained with an untreated monofilament.     

Infinite multiplication factor of low-enriched UO2–concrete system

The possibility of criticality of fuel debris in a form of uranium dioxide (UO₂)–concrete mixture is evaluated by calculating the infinite multiplication factor (k _∞) for a study of criticality control on the fuel debris generated through the molten core concrete interaction in a severe accident of a light water reactor. The infinite multiplication factor can be greater than unity, which means that handling of the mixture is subject to criticality control. This paper shows that concrete provides efficient neutron moderation and points out the necessity of further investigations on the criticality of UO₂–concrete system for actual handling of fuel debris.