Proton spin relaxation study with pulsed NMR on the plasticization of Na+ ion-selective electrode membranes prepared from PVCs with different degrees of polymerization.

The proton spin-spin relaxation times (T2) of ion-selective electrode membranes with differences in the polymerization degree of the incorporated poly(vinyl chloride) (PVC) polymers were investigated. T2 measurements were performed using Hahn-Echo, Solid-Echo and Carr-Purcell-Meiboom-Gill (CPMG) pulse sequences. Analyses of the T2 measurements by Hahn-Echo pulse sequences could realize the estimation of the homogeneity and compatibility for a series of ion-selective electrode membranes and reveal a relationship with the electromotive force (EMF) response in the low-concentration region of the Na+ ions. On the other hand, the normalized derivative spectra from T2 measurements by Solid-Echo and CPMG pulse sequences could approximately visualize the degree of plasticization for such potentiometric polymeric membranes. Moreover, differences in the polymerization degrees of the incorporated PVCs were scarcely found to affect the selectivity coefficients of the Na+-ISEs based on bis(12-crown-4).

A C3-substituted cyclotriveratrylene derivative with 8-quinolinyl groups as a fluorescence-enhanced probe for the sensing of Cu2+ ions.

C 3-Substituted cyclotriveratrylene (CTV) derivatives were considered suitable candidates for recognition compounds due to their unique structures. In this study, a C3-substituted CTV derivative with three fluorogenic 8-quinolinyl groups (1) was designed and prepared as a fluorescent probe. The synthesized CTV derivative 1 exhibited a selective response of fluorescence enhancement toward Cu2+ ions among the examined cations. The sensing ability of CTV derivative 1 toward Cu2+ ions was superior to that of the previously reported C3-substituted CTV derivative with three 2-quinolinyl groups (2). It is, thus, suggested that the CTV structure plays an important role in selective sensing ability toward Cu2+ ions since the mono-quinoline compound 5 showed fluorescence properties toward the Cr3+, Fe2+ and Fe3+ ions in addition to Cu2+ ions. In other words, the high Cu2+ ion-selectivity of CTV derivative 1 was demonstrated even in the presence of other co-existing examined cations. Moreover, it was found that CTV derivative 1 could work as a reversible fluorescence-enhanced probe toward Cu2+ ions by the simple addition of Et3N.

Investigation of Polyurethane Matrix Membranes for Salivary Nitrate ISFETs to Prevent the Drift.

We have investigated human-stress monitoring by making use of salivary nitrate, which can be a candidate for stress markers, with ion-selective field-effect transistors (ISFETs). ISFETs are suitable for on-site single-drop analysis of salivary nitrate within 10 s. However, when ISFETs are used for salivary nitrate, ISFETs have a problem that is called the initial drift. The initial drift makes accurate nitrate monitoring difficult. Thus, the purpose of this study is to prevent the initial drift and to search for a new, simple polymer to possess a better performance of sensor responses than conventional matrix membranes, such as PVC. In this research, we investigated ISFETs using specific matrix membranes, for example KP-13, Pellethane®--, and P7281-PU. The initial drift was evaluated from the fluctuations of the response values generated by the ISFETs when immersed in saliva or aqueous solution. As a result, P7281-PU showed a prevention effect on the initial drift, both in the whole saliva and in various solutions. Furthermore, the cause of drift may be H+ diffusion, and the drift prevention effect of P7281-PU may be affected by urethane bond capturing H+ in the ion-selective membrane. This result suggests that a continuous nitrate monitoring is feasible and may be applied to wearable sensors.

Enhanced chemiluminescence for trazodone trace analysis based on acidic permanganate oxidation in concurrent presence of rhodamine 6G.

A new sensitized chemiluminescence method by acidic permanganate oxidation was developed for the sensitive determination of trazodone. A fluorescent dye as used rhodamine 6G to increase a chemiluminescence intensity. Under optimum conditions, the liner range of the calibration curve was obtained for 1-5000 nmol/L. The limit of detection was calculated from 3σ of a blank was 0.23 nmol/L. The coexistent ions and substances had no interference with the chemiluminescence measurement. The chemiluminescence spectra were measured to elucidate a possible mechanism for the system. The present method was satisfactorily used in the determination of the drugs in pharmaceutical samples and animal serums.

Bis(1-pyrenylmethyl)-2-benzyl-2-methyl-malonate as a Cu2+ Ion-Selective Fluoroionophore.

A new malonate possessing two pyrene moieties was synthesized as a fluoroionophore, and its structure and fluorescence spectroscopic properties were investigated. When excited at 344 nm in acetonitrile/chloroform (9:1, v/v), the synthesized bispyrenyl malonate has the fluorescence of intramolecular excimer (λem = 467 nm) emissions and not a pyrene monomer emission (λem = 394 nm). A large absolute fluorescence quantum yield was obtained in the solid state (ΦPL = 0.65) rather than in solution (ΦPL = 0.13). X-ray crystallography analysis clarified the molecular structure and alignment of the bispyrenyl malonate in the crystal phase, elucidating its fluorescence spectroscopic properties. Such analysis also suggests there are intramolecular C-H···π interactions and intermolecular π···π interactions between the pyrenyl rings. Interestingly, the synthesized bispyrenyl malonate exhibits excellent fluorescence sensing for the Cu2+ ion. Remarkable fluorescence intensity enhancement was only observed with the addition of the Cu2+ ion.

Factors associated with the leftover rate of side dishes in Japanese school lunches.

This study investigated the leftover rate of side dishes in school lunches provided by communal kitchens in Japan's Chugoku region, with a focus on vegetable dishes supplied in containers and three types of menu items served daily to 20 elementary and junior high schools in communal kitchen A for 116 days. First, the leftovers in the containers that were returned to the communal kitchen were weighed and combined. The study then compared outside temperature, distance from communal kitchen A, school type, number of students per class, assignment of nutrition teachers, and time elapsed after cooking. Finally, we examined the relationship between these factors and the leftover rate using multiple regression analysis. The median leftover rate was 20.1% (0-96.9) for 250 side dishes with a high leftover rate; however, this was widely distributed. The number of students per class, assignment of nutrition teachers, and time elapsed after cooking were strongly related to the leftover rate; the adjusted coefficient of determination, R2, was 0.236. The regression results indicated that regarding the side dish leftover rate, the standardized coefficient, ß, was 0.414, 0.215, 0.107, 0.093, and 0.094 for the number of students per class, assignment of nutrition teacher, the time elapsed after the end of cooking, distance from communal kitchen A, and presence of seaweed, respectively (p<0.001). Dietary education by homeroom and nutrition teachers and reducing the time elapsed after cooking impacts students' awareness and preferences, which may decrease the leftover rate.

A Thickening Agent Using Dioscorea japonica Powder Exhibits Suitable Properties for People with Dysphagia.

In an aging society, the novel concept of added food functionality in a dysphagia diet is necessary for preventing diseases and maintain nutrition intake. The present study evaluated the utilization of Dioscorea japonica as a thickened liquid for people with dysphagia due to its unique physical properties and beneficial effects on chronic inflammation. The viscosity of the prepared thickened liquid using freeze-dried Dioscorea japonica powder was compared with those of xanthan gum and commercially available thickened liquids in selected conditions resembling to cooking. Dioscorea japonica powder showed high versatility, because the viscosity of its thickened liquid could be easily adjusted by modifying its blending amount and temperature. The thickened liquid of Dioscorea japonica had the most stable viscosity among the thickened liquids when NaCl was added and exhibited excellent resistance to α-amylase, similar to that of the other thickened liquids. The viscosity of the thickened liquid of Dioscorea japonica was relatively stable on changing the pH, but it was slightly unstable when the temperature changed. Overall, the thickened liquid of Dioscorea japonica powder has excellent viscosity stability, comparable to or better than commercially available thickened liquids, and is expected to be used as a new thickened liquid with added food functionality.

Binding of Stimuli-Responsive Ruthenium Aqua Complexes with 9-Ethylguanine.

Stimuli-responsive ruthenium complexes proximal- and distal-[Ru(C10tpy)(C10pyqu) OH2]2+ (proximal-1 and distal-1; C10tpy = 4'-decyloxy-2,2':6',2″-terpyridine and C10pyqu = 2-[2'-(6'-decyloxy)-pyridyl]quinoline) were experimentally studied for adduct formation with a model DNA base. At 303 K, proximal-1 exhibited 1:1 adduct formation with 9-ethylguanine (9-EtG) to yield proximal-[Ru(C10tpy)(C10pyqu)(9-EtG)]2+ (proximal-RuEtG). Rotation of the guanine ligand on the ruthenium center was sterically hindered by the presence of an adjacent quinoline moiety at 303 K. Results from 1H NMR measurements indicated that photoirradiation of a proximal-RuEtG solution caused photoisomerization to distal-RuEtG, whereas heating of proximal-RuEtG caused ligand substitution to proximal-1. The distal isomer of the aqua complex, distal-1, was observed to slowly revert to proximal-1 at 303 K. In the presence of 9-EtG, distal-1 underwent thermal back-isomerization to proximal-1 and adduct formation to distal-RuEtG. Kinetic analysis of 1H NMR measurements showed that adduct formation between proximal-1 and 9-EtG was 8-fold faster than that between distal-1 and 9-EtG. This difference may be attributed to intramolecular hydrogen bonding and steric repulsion between the aqua ligand and the pendant moiety of the bidentate ligand..

Deep-sea in situ determination of sulfide using a sensitized chemiluminescent terbium complex.

A new chemiluminescence (CL) method based on the chemiluminescent reaction between sulfide and an acidic permanganate solution was used to quantify sulfide in seawater. A terbium-pipemidic acid complex was used as CL enhancer. The method was used to determine sulfide in the concentration range of 1-30 µmol/L in artificial seawater samples. The limit of detection of the method was 21 nmol/L sulfide. The sensitivity of the CL method was eight times higher than that of the CL method reported previously. Br- ions, which are conservative ions, interfered with sulfide. We investigated the effects of salinity, water temperature, and interfering chemicals,such asheavy-metal ions and organic matter, on the performance of the CL method. In addition, sulfite-spiked natural seawater samples were analyzed. The results demonstrate that the CL method can be used to develop a deep-sea sulfide analyzer.

A visible-light and temperature responsive host-guest system: the photoisomerization and inclusion complex formation of a ruthenium complex with cyclodextrins.

In the present study, we investigated the visible-light- and thermal-stimuli-responsive properties of a host-guest system based on proximal- and distal-[Ru(C10tpy)(C10pyqu)OH2]2+ complexes (proximal and distal-1; C10tpy = 4'-decyloxy-2,2':6',2''-terpyridine and C10pyqu = 2-[2'-(6'-decyloxy)-pyridyl]quinoline). The analogs of such ruthenium aqua complexes are well-known as metallodrugs and catalysts. The proximal isomer has a dicationic ruthenium center and hydrophobic alkyl chains on both ligands, with the two alkyl chains located close together. According to titration experiments, proximal-1 binds to γ-cyclodextrin (γ-CD) in aqueous media with a binding constant of K1:1 = 520 ± 60 M-1, which is much higher than the corresponding values for α-CD and ß-CD. Additional experiments indicated that the two alkyl chains were incorporated into the cavity of γ-CD. The photoisomerized complex, distal-1, exhibits thermal isomerization back to proximal-1 in the dark with a kobs = 7.26 ± 0.01 × 10-6 s-1. In the presence of γ-CD, the corresponding rate constant is 1.3 times higher, which is attributed to the steric repulsion of cyclodextrin and the aqua ligand by the inclusion complex formation between distal-1 and the cyclodextrins. The distal isomer has a lower affinity for CDs because the two alkyl chains are more separated. The repeated application of external stimuli to a mixture of proximal-1 and γ-CD resulted in a reproducible and reversible host-guest complex formation.

A new solvent polymeric membrane electrode incorporating poly(N-isopropylacrylamide) as a polymer.

Here, we report on a new solvent polymeric membrane electrode incorporating thermoresponsive poly(N-isopropylacrylamide) (PIPA) as a polymer with the lower critical solution temperature (LCST) of ca. 32 °C. The response of the solvent polymeric membrane electrode to the ions changes at 25 and 40 °C. Pulsed NMR analyses demonstrated the novel effects of the LCST behaviour on the potentiometric polymeric membrane.

Pulsed NMR analysis of ion-selective electrode membranes.

A novel method for evaluation of ion-selective electrode membranes was reported with the proton spin-spin relaxation time T(2) by pulsed NMR. The proton spin-spin relaxation time T(2) measurements provided valuable information about properties of the whole membrane matrix. The softer potentiometric liquid membrane possessed a large fraction F(L) providing relatively longer T(2) value. Pulsed NMR method can quantify the degree of the plasticization of ion-selective electrode membranes.

Arachidonate 12S-lipoxygenase of platelet-type in hepatic stellate cells of methionine and choline-deficient diet-fed mice.

A role of 12-lipoxygenase in the progression of non-alcoholic steatohepatitis (NASH) is suggested, although the underlying mechanism is not entirely understood. The catalytic activity of 12S-lipoxygenase that was hardly observed in liver cytosol of normal chow-fed mice was clearly detectable in that of NASH model mice prepared by feeding a methionine and choline-deficient (MCD) diet. The product profile, substrate specificity and immunogenicity indicated that the enzyme was the platelet-type isoform. The expression levels of mRNA and protein of platelet-type 12S-lipoxygenase in the liver of MCD diet-fed mice were significantly increased compared with those of normal chow-fed mice. Immunohistochemical analysis showed that platelet-type 12S-lipoxygenase colocalized with α-smooth muscle actin as well as vitamin A in the cells distributing along liver sinusoids. These results indicate that the expression level of platelet-type 12S-lipoxygenase in hepatic stellate cells was increased during the cell activation in MCD diet-fed mice, suggesting a possible role of the enzyme in pathophysiology of liver fibrosis.

Eicosapentaenoic acid supplementation for chronic hepatitis C patients during combination therapy of pegylated interferon alpha-2b and ribavirin.

Eicosapentaenoic acid (EPA) (1.8 g/day) was administered to 12 chronic hepatitis C patients receiving combination therapy of pegylated interferon (PEG-IFN) alpha-2b and ribavirin for 48 weeks (EPA group). Twelve patients were not administered EPA (control group). All patients also received vitamin E and C (300, 600 mg/day, respectively) during the therapy. Serum alanine aminotransferase improved to a normal level in 8 of 12 patients from the EPA group and 6 of 12 patients from the control group after 12 weeks. Lymphocyte counts decreased significantly after 8 weeks in the control group, but not the EPA group. T-helper (Th) 1 decreased after 4 weeks in the control group, but not in the EPA group (two-way ANOVA; P < 0.05). Th1/Th2 ratios were elevated in 9 of 12 patients in the EPA group, and 3 out of 12 in the control group (P < 0.05) after 8 weeks. After 12 weeks, the arachidonic acid/EPA molar ratio of erythrocyte membrane phospholipid correlated negatively with the leukocyte count (n = 24, r = -0.439, P < 0.05) and the neutrophil count (n = 24, r = -0.671, P < 0.02). The hemoglobin level improved after 48 weeks compared with 24 weeks in only the EPA group. These findings suggest that EPA supplementation may be useful in therapy for chronic hepatitis C.

Effect of Simulated Patient Practice on the Self-Efficacy of Japanese Undergraduate Dietitians in Nutrition Care Process Skills.

OBJECTIVE: To examine the effect of an adapted simulated patient (SP) intervention on self-efficacy in nutrition care process skills. DESIGN: A repeated-measures design using a 25-item survey divided into 7 nutrition professional practice competencies (PPCs) employing a 5-point self-efficacy scale (1 = lowest to 5 = highest) administered immediately before and after the intervention. SETTING: A private Japanese university. PARTICIPANTS: Ninety Japanese third-year dietetics undergraduates aged 20-38 years. INTERVENTION: An adapted SP activity practicing nutrition care process skills for the infirm elderly population. MAIN OUTCOME MEASURES: Pre- to postintervention self-efficacy response scores and feedback. ANALYSIS: Mean preintervention survey scores were used to divide participants into statistical quartiles (Q1 indicated lowest mean scores and Q3, highest mean scores). Wilcoxon signed-rank tests compared each PPC's pre- and postintervention means. Kruskal-Wallis tests examined changes in quartiles' scores within each PPC. RESULTS: Self-efficacy improved significantly in PPCs relating to application of appropriate medical ethics and interpersonal skills (P = .02), appropriate nutrition assessment (P = .04), and creation of a nutrition management plan and nutrition intervention (P = .03). Self-efficacy of Q1 and Q2 rose significantly in most PPCs, although not for acting as a dietitian within a medical care team, whereas that of Q3 decreased for all PPCs. CONCLUSIONS AND IMPLICATIONS: Among initially low self-efficacy dietetics undergraduates, the SP intervention enhanced self-efficacy in 3 of the 6 PPCs practiced directly and may facilitate more realistic self-views among initially high self-efficacy students. However, further research in the design, implementation, and efficacy of this type of training is recommended to gauge its effects on the quality of related professional practice.

Dietary intake, neutrophil fatty acid profile, serum antioxidant vitamins and oxygen radical absorbance capacity in patients with ulcerative colitis.

Nutrition may play an important role in the pathogenesis and treatment of ulcerative colitis. Several studies suggest an association between dietary factors and the onset of ulcerative colitis; however, only few studies have examined the relationship between dietary intake and relapse of ulcerative colitis. The aim of this study was to assess the dietary intake and antioxidative capacity of ulcerative colitis patients and to elucidate the efficacy of dietary therapy for ulcerative colitis. Dietary intake, fatty acid composition of phospholipids in plasma and neutrophils, serum fat-soluble vitamin levels, and oxygen radical absorbance capacity were analyzed in 29 ulcerative colitis patients (7 males and 22 females), who were treated at the Department of Gastroenterology, Okayama University Hospital. Total fat intake, fat energy ratio and linoleic acid intake were significantly lower, while protein and carbohydrate intakes were significantly higher, in the patients than age- and sex-matched controls. In the neutrophil phospholipids of ulcerative colitis patients, significantly higher levels of linoleic aicd and arachidonic acid and a lower level of eicosapentaenoic acid were observed. The concentrations of serum retinol and beta-carotene but not alpha-tocopherol were significantly lower and serum oxygen radical absorbance capacity was also lower than in the controls. Significant correlations between serum oxygen radical absorbance capacity and retinol (r = 0.567, p = 0.0031), alpha-tocopherol (r = 0.560, p = 0.0036) and beta-carotene (r = 0.440, p = 0.0279) concentrations were observed in the ulcerative colitis patients. A diet restricting the intake of linoleic acid and supplemented with eicosapentaenoic acid and antioxidative vitamins may be recommendable for the nutritional management of ulcerative colitis patients.

Zinc supplementation prevents the increase of transaminase in chronic hepatitis C patients during combination therapy with pegylated interferon alpha-2b and ribavirin.

We investigated the effects of zinc supplementation on clinical observations in chronic hepatitis C patients receiving pegylated interferon (PEG-IFN) alpha-2b plus ribavirin combination therapy. Patients were randomly allocated to receive 150 mg polaprezinc (zinc group, n=11) or no supplement (control group, n=12) daily in addition to PEG-IFN alpha-2b plus ribavirin therapy and 300 mg vitamin E and 600 mg vitamin C supplementation daily for 48 wk. Among the patients who continued treatment, the serum alanine aminotransferase (ALT) level at 12 wk in the zinc group was significantly lower than that in the control group. All patients in the zinc group (9/9) and 67% (8/12) of the control patients at 24 wk, and all patients in the zinc group (7/7) and 60% (6/10) of the control patients at 48 wk showed a decrease in serum ALT levels to within the normal range (7-44 U/L). HCV RNA disappeared in all patients (7/7) in the zinc group and in 8 of 10 control patients at 48 wk. Polaprezinc supplementation decreased plasma thiobarbituric acid reactive substances and prevented the decrease of polyunsaturated fatty acids of erythrocyte membrane phospholipids. No significant differences were observed in the dosage of medicines or other clinical data during the treatment. These observations indicate that polaprezinc supplementation may have induced some antioxidative functions in the liver which resulted in reduced hepatocyte injury during PEG-IFN alpha-2b plus ribavirin therapy.

Vitamin E and C supplementation prevents decrease of eicosapentaenoic acid in mononuclear cells in chronic hepatitis C patients during combination therapy of interferon alpha-2b and ribavirin.

OBJECTIVE: We investigated the effects of vitamin E and C supplementation on the fatty acid composition of mononuclear cells and on the clinical observations in patients who had chronic hepatitis C and received interferon-alpha-2b (IFN-alpha-2b) and ribavirin combination therapy. METHODS: Patients were randomly allocated to receive daily 500 mg of vitamin E and 750 mg of vitamin C (vitamin group, n = 14) or no supplement (non-vitamin group, n = 16) in addition to IFN-alpha-2b and ribavirin therapy. The fatty acid composition of mononuclear cell phospholipids was analyzed before and at 2, 4, and 8 wk after treatment. RESULTS: After vitamin supplementation, plasma and red blood cell alpha-tocopherol and plasma ascorbic acid levels increased in the vitamin group. Serum levels of alanine aminotransferase decreased significantly after 2 wk of treatment in both groups. At the start of treatment, a lower level of eicosapentaenoic acid (EPA) and a higher level of the molar ratio of arachidonic acid to EPA in mononuclear cells were observed in the present patients compared with healthy volunteers, and a significant correlation between the molar ratio and serum alanine aminotransferase level was found. The EPA level of mononuclear cells was maintained in the vitamin group during treatment, whereas a significant decrease was observed in the non-vitamin group at 4 and 8 wk after treatment. CONCLUSIONS: Antioxidant vitamin supplementation during IFN-alpha-2b and ribavirin therapy prevented a decrease in EPA of mononuclear cell phospholipids. If a further decrease in the ratio of arachidonic acid to EPA can be achieved by using oral EPA supplementation, the efficacy of IFN-alpha-2b and ribavirin therapy may be improved.

Effects of eicosapentaenoic acid supplementation in the treatment of chronic hepatitis C patients.

Eicosapentaenoic acid (EPA) has been shown to exert anti-inflammatory actions. To evaluate the effects of EPA on chronic hepatitis C, we administered EPA ethyl ester capsules to patients receiving the combination therapy of interferon alpha-2b and ribavirin. EPA (1,800 mg/d) was supplemented in combination with vitamin E (300 mg/d) and C (600 mg/d) to 5 chronic hepatitis C patients (EPA group). Five patients were administered vitamin E and C but not EPA (control group). Blood samples were obtained before and after 4, 8, 12 and 24 wk of therapy and analyzed for fatty acid compositions of erythrocyte and plasma and serum 8-hydroxy-2'-deoxyguanosine. EPA in erythrocyte membrane rose to 3 fold the basal level in the EPA group, while it decreased significantly in the control group after 24 wk of therapy. Lymphocyte counts in the EPA group increased to 120.8 +/- 25.4% after 4 wk of therapy and maintained the basal level throughout therapy, whereas the counts decreased significantly in controls. The serum alanine aminotransferase level was improved significantly in the EPA group. Changes in lymphocyte counts following 24 wk of therapy correlated with the EPA level in erythrocyte. The serum 8-hydroxy-2'-deoxyguanosine level at 24 wk in the EPA group was significantly lower than that in controls. These observations may suggest the beneficial effect of EPA supplementation in the treatment of chronic hepatitis C patients.

Influence of Introduced Substituents on the Anion-selectivity of [14]Tetraazaannulene Complexes.

Nickel(II) complexes of [14]tetraazaannulene derivatives incorporating aromatic rings into their azaannulene framework were synthesized, and the anion-selectivity of the [14]tetraazaannulene nickel complexes 1 - 4 was evaluated by potentiometric measurements with solvent polymeric membrane electrodes. All of the [14]Tetraazaannulene nickel complexes, except 3, were found to exhibit high selectivity for the I(-) ion over the SCN(-) ion, although considerable interference of the ClO4(-) ion was observed in all 1 - 4 complexes. Concerning the anion-selectivities of 1 and 4, the incorporation of naphthalene rings into the azaannulene framework decreased not only the interference of the ClO4(-) ion but also the I(-) ion-selectivity over the SCN(-) ion. Comparison studies between the dibenzotetraaza[14]annulene nickel complexes 1 - 3 indicated that differences in the attached substituents of the [14]tetraazaannulene nickel complexes greatly influenced the ion-selectivity as ionophores. According to our computational results, the ionophoric properties of [14]tetraazaannulene nickel complexes 1 - 4 were influenced by their electrostatic properties rather than their topological properties.