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2022

The feasibility of fabricating Janus particles based on phase separation between a hard fat and a biocompatible polymer was investigated. The solvent evaporation method used involved preparing an oil-in-water (o/w) emulsion with a mixture of poly (lactic-co-glycolic) acid (PLGA), hard fat, and an organic solvent as the oil phase and a polyvinyl alcohol aqueous solution as the water phase. The Janus particles were formed when the solvent was evaporated to obtain certain concentrations of PLGA and hard fat in the oil phase, at which phase separation was estimated to occur based on the phase diagram analysis. The hard fat hemisphere was proven to be the oil phase using a lipophilic dye Oil Red O. When the solvent evaporation process was performed maintaining a specific volume during the emulsification process; Janus particles were formed within 1.5 h. However, the formed Janus particles were destroyed by stirring for over 6 h. In contrast, a few Janus particles were formed when enough water to dissolve the oil phase solvent was added to the emulsion immediately after the emulsification process. The optimized volume of the solvent evaporation medium dominantly formed Janus particles and maintained the conformation for over 6 h with stirring. These results indicate that the formation and stability of Janus particles depend on the rate of solvent evaporation. Therefore, optimization of the solvent evaporation rate is critical to obtaining stable PLGA and hard fat Janus particles. more...

text, 紀要論文 / Departmental Bulletin Paper

A novel palladium-catalyzed hydrophosphination of alkynes with tetraphenyldiphosphine takes place regioselectively to provide vinylic phosphines, which undergo air-oxidation during workups, affording the corresponding vinylphosphine oxides in good yields. more...

Time-resolved and steady-state electron paramagnetic resonance (EPR) spectra have been observed for the lowest excited triplet (T(1)) states of phenazine (Phz) and its singly protonated cation (phenazinium) in sulfuric acid-ethanol mixtures at 77K. The single protonation appears to have little effect on the anisotropic sublevel populating rates of the T(1) state of phenazine. However, the zero-field splitting (ZFS) parameter D decreases on the protonation, reflecting the increase of delocalization of the two unpaired electrons. The sublevel preferentially populated by intersystem crossing (ISC) is T(y) in both phenazine and phenazinium (the y-axis is parallel to the in-plane long axis). From the analysis of the observed anisotropy in the ISC rates and the semi empirical molecular orbital calculations of the ZFS parameters, we concluded that the T(1) state of phenazinium is the (3)A(1)(pipi*) state. more...

Highly pure octacyanophthalocyaninatoiron complex ( FePcOC ) was synthesized by the reaction between tetracyanobenzene and iron(II) acetate in sulfolane. The complex was further converted into a coordination polymer by the reaction with tetrazine as an axial μ-bridge ligand. The charge/discharge characteristics of lithium cells with an FePcOC cathode were studied. The capacity and the energy density based on the quantity of cathode active material were ca 105 mAh g-1 and 210 Wh kg-1 respectively. Better results were obtained when the cathode material was replaced by the coordination polymer. It was found that the FePcOC and corresponding polymer complex are promising candidates as an active cathode material for lithium secondary batteries. more...

Single-ionic conductors, which display lithium ion migration exclusively (without anion migration), have been realized as the polymeric solid electrolytes with lithium orthoaluminate repeating units carrying oligo(oxyethylene) main chain and two side chains of endomethoxy{oligo(oxyethylene)}. The ionic conductivity of the aluminate polymer complexes is about 10−6–10−7 S/cm at room temperature. Thin film lithium secondary batteries were fabricated into 5.5 cm×4.5 cm×0.02–0.03 cm (thick) cells from lithium foil (anode), aluminate polymer complex (electrolyte) and TiS2 (cathode). These batteries show minimal decay of output voltage upon constant current discharging and their capacity of first cycle was about 146 mA h/g of active cathode material. By contrast typical bi-ionic conductor of (aluminate polymer complex+5% LiClO4) hybrid system showed, on the contrary, rapid decay of output voltage, due to polarization. more...

Highly pure metal-free octacyanophthalocyanine (H2PcOC) was further converted into two-dimensional polymers (PPcCN) by solid-phase reaction in presence of tetracyanobenzene. PPcCN showed the electric conductivity as high as about 5·10−4 S cm−1, 2-orders of magnitude larger than that of H2PcOC. Since PPcCN exhibited reversible multi-electron redox reaction at relatively positive potential near −0.3 V vs. NHE and was insoluble throughout the redox reaction in any organic electrolyte solutions, this polymer is useful in lithium (ion) rechargeable batteries as cathode-active material. When the depth of discharge was controlled to 150 mAh g−1, the cell composed of [metallic Li/electrolyte/PPcCN] gave very stable cycle property for several hundred charge-discharge cycles with the average output voltage of 2.73 V and the energy density of 409 Wh kg−1, of which value is comparable to commercial lithium ion batteries based on Lix(CoO2)y cathode. Copyright © 2001 John Wiley & Sons, Ltd. more...

Metal-free octacyanophthalocyanine (H2PcOC), one of the strongest organic acceptors with fair stability and electric conductivity, was examined as the cathode-active material of a lithium battery composed of (metallic lithium/electrolyte solution/H2PcOC). The capacity and energy density based on the quantity of cathode-active material were 137 mA h g−1 and 222 W h kg−1 at 1 V cutoff, respectively. The cycle life of this battery exceeded 20 at the discharge depth of three electron reduction (112 mA h g−1) per H2PcOC unit. It was found that H2PcOC is a promising candidate as the cathode-active material for lithium secondary batteries. more...

By the addition of extra salts such as LiBF4 into a single-ionic polymer solid electrolyte, poly[lithium bis{endomethyl-oligo(oxyethylene)oxy}-oligo(oxyethylene)oxy-aluminate], the balance of transport number was controlled from t+ = 1 (t− = 0: single-ionic) to t+ ≈ t− ≈ 0.5. Since the state of t+ ≈ t− could be realized over a wide concentration range of added LiBF4, this type of bi-ionic conductor could be useful in rechargeable batteries such as in which the concentration of LiBF4 fluctuates during the charging/discharging processes by the ingress/egress of Li+ and . The [Li/electrolyte/poly(aniline)+BF4−] battery with transport number controlled electrolyte showed a distinct plateau voltage in discharge curves. Copyright © 2000 John Wiley & Sons, Ltd. more...

Improvement of electrical conductivity was attempted by polymerizing octacyanometallophthalocyanine (MPcOC; M ≡ Fe , Co ) units into one-dimensional molecular complexes. The synthetic route to MPcOC was established by reacting tetracyanobenzene with a metal(II) acetate in sulfolane. Poly(μ-pyrazine)octacyanophthalocyaninatoiron(II) and -cobalt(II) were synthesized and their doping with lithium was carried out. The Fe (II) and Co (II) octacyanophthalocyanine complexes showed good electrical conductivities of the order of 10-8-10-4 S cm -1. The electrical conductivities of the lithium-doped complexes were improved by two or three orders of magnitude in comparison with the corresponding monomeric and polymeric complexes. more...

Poly[(μ-1,4-diisocyanobenzene)octacyanophthalocyaninatoiron(II)],[FePcOC(dib)]n, was synthesized and its doping with lithium was studied. The chemical, spectral and electric properties of bridged polymer were characterized by IR, UV–vis and 1 H -NMR. The chain length of [FePcOC(dib)]n determined by gel permeation chromatography and TOF-mass was 12–15. The coordination state of the central metal of [FePcOC(dib)]n was iron(II) according to the results of ESCA analysis. In spite of its relatively large inter-ring distance, [FePcOC(dib)]n showed powder conductivity in the range of 10−7 S/cm. With lithium-doping, its electrical conductivity was improved by two orders of magnitude. more...

To improve the conductivity of recently reported single-ionic lithium orthoaluminate complex polymer electrolytes, the structure of the complex unit was changed from [Al(OR)4]- to [Al(SR)4]-, carry... more...

側鎖に分子超分極率の大きいp-ニトロフェニル基を有するポリフマレートを合成し. そのZ型LB膜を構築して第2次高調波発生 (SHG) 特性を調査した. フマレートは適当なかさ高さを有する分枝アルキルエステル構造でないと重合しにくいため, ヒドロキシネオペンチルイソプロピルフマレートを選択し, ラジカル重合体 (PF1) の側鎖-OH基と過剰のp-ニトロフェニルイソシアナートを高分子反応させて相当するポリ (イソブロピルp-ニトロフェニルカルバモイロキシネオペンチルフマレート) (PF2) を得た. この高分子反応は付加反応であるため, ほぼ100%非線形光学 (NLO) 発色団を導入できた. PF1, PF2のいずれも純水副相上で安定な単層膜 (L膜) を形成し, シラザンによる疎水化処理ガラス・石英ガラス基板に垂直浸漬法で累積できた. 交互累稽トラフによりZ型累積されたPF2膜は膜厚方向に自発分極が残っており, Nd: YAGレーザーを基本波として入射するとSHGが観測された. SHG強度の1/2乗と膜厚 (累積数) は比例関係にあり, SHGの起源は界面ではなく, 膜のバルク相に由来することがわかった. この膜厚方向の異方性は, 気/水界面でのL膜形成時にNLO発色団の配向が起きるためと考えられるが, その規制力は弱い. 事実, PF2スピンコート膜を加温しながらコロナポーリング処理して強制的な配向を発現させたときには, Z型LB膜の約5倍のSHG強度を示した. 分極基をつなぐネオペンチルの二つのメチレンが自由回転しやすいことに起因すると思われる. more...

Main-chain anionic polymers with lithium cations, which have oligo(oxyethylene)aluminate chain backbones attached with two side chains of endo-methoxy[oligo(oxyethylene)], were prepared, and their ionic conductivities are reported. The ac conductivity of aluminate polymer complex was about 10-6−10-7 S cm-11 at room temperature. As the constant current was observed for [Li/aluminate polymer complex/Li] cells under dc electric field, the single-ionic conduction was confirmed. more...

Welded tuffs in the Bogopol and Sijanov groups were sampled at 27 sites from 12 caldera formations in the Sikhote Alin mountain range around Kavalerovo (44.3°N, 135.0°E) for chronological and paleomagnetic studies. K Ar age dates show that the welded tuffs erupted between 66 Ma and 46 Ma. All sites yield reliable paleomagnetic directions, with unblocking temperatures higher than 560°C. The high-temperature component at 12 sites and the medium-temperature component at 3 sites in the Bogopol Group show reversed polarity ( D = 193.7°, I = −57.6°,α 95 = 8.1°). The high-temperature component at 11 sites in the Sijanov Group showed both reversed and normal polarities and its mean direction reveals no detectable deflection from north ( D = −2.9°, I = 59.6°,α 95 = 11.2°). The combined paleomagnetic direction of the two groups yields a paleomagnetic pole of 250.5°E, 84.1°N (A 95 = 8.8°), which falls near Cretaceous paleomagnetic poles from Outer Mongolia, Inner Mongolia, the North China Block and the South China Block. The Sikhote Alin area appears not to have been subjected to detectable motion with respect to East Asia since about 50 Ma. This implies that the Sikhote Alin area behaved as an integral part of East Asia during the opening of the Japan Sea at about 15 Ma. However, significant separation between the paleomagnetic poles of East Asia and Europe during the Jurassic-Paleogene implies a major relative movement between these two blocks since the Paleogene. more...

The patient was a 74-year-old woman who had been obese since age 18. Her obesity was refractory to dietary manipulation. She had been suffering from increasing dyspnea for several months and eventually could not even move. She was admitted to a hospital and diagnosed as having heart failure. Although her cardiac function recovered with medical treatment, her symptoms did not improve. The patient was then sent to our hospital. On admission, her height and weight were 149 cm and 81.9 kg, respectively, yielding a body mass index (BMI) of 36.6 kg/m2. Arterial blood gas analysis in room air revealed hypoxemia and an apnea index of 27 per hour. She was given a daily 500-1000 kcal diet. After four months of treatment, her weight decreased to 65 kg with a BMI of 29.3 kg/m2. Weight reduction together with the usage of progesterone-derivatives resulted in marked improvement of sleep apnea. The apnea index decreased to 3/h and arterial blood gas values normalized. This patient seemed to have suffered from both obesity hypoventilation syndrome and sleep apnea syndrome. Improvement of respiratory function was achieved through relief of airway obstruction and weight reduction, with activation of the respiratory center due to progesterone treatment. more...

A novel palladium-catalyzed hydrophosphination of alkynes with tetraphenyldiphosphine takes place regioselectively to provide vinylic phosphines, which undergo air-oxidation during workups, affording the corresponding vinylphosphine oxides in good yields. more...

The one-dimensional coordination polymers based on octacyanophthalocyanatoiron (FePcOC) and bidentate axial bridging ligands such as pyrazine, tetrazine, and diisocyanobenzene (dib) were synthesized and used as the cathode material of secondary lithium batteries. The lithium//electrolyte solution//FePcOC-dib polymer cell gave the best performance due to its stability upon discharging process. Especially when the 0.5 M LiPF 6 /dimethoxyethane solution was used as the electrolyte, the cell exhibited the energy density of 475 Wh kg -1 with the average output voltage of 3.2 V. more...

Lithium salts, such as LiBF 4 . LiClO 4 . and LiPF 6 . were added to the single-ion solid polymer electrolyte poly[lithium bis{endomethyl-oligo(oxyethylene)oxy}oligo(oxyethylene)oxyaluminate] in which Li + is the only mobile ion, to adjust the transport number from t + = I (t - = 0: single-ionic) to t + t - 0.5, When LiBF 4 was used, the average transport number was found to deviate little over a wide salt concentration range. This characteristic meets a requirement for Li/polyaniline n+ (BF 4 - ) n batteries in which the salt concentration fluctuates with the ingress/egress of Li + and X - during the charging/discharging processes. A Li/polyaniline n+ (BF 4 - ) n cell using this transport-number-adjusted electrolyte exhibited a distinct discharge plateau at a reasonably high voltage and excellent cycle stability. more...

A zonal rotor technique for the preparation of synaptosomes in bulk from bovine brain frontal cortex based on an impirical transformation of a small-volume discontinuous sucrose density gradient arrangement is presented in detail. The procedure yields new information concerning synaptosomes prepared in sucrose gradients. Cerebroside analysis and electron microscopy show myelin contamination to be restricted to the leading, less dense edge of the synaptosomal profile, free mitochondria to the trailing, more dense edge. Exclusion of fringe areas yields a highly purified synaptosome preparation which entirely enters the next dense layer beyond the 0.8 : 1.2 M sucrose interface. This interface collects most of the oubain-sensitive (Na+, K+) adenosine triphosphatase activity. The purified synaptosomes display very high intrinsic sialidase activity and are rich in di-, tri-, and tetrasialogangliosides, the preferred substrates for the enzyme. Up to 90% of the cholinesterase activity in the zonal rotor synaptosome preparation is specific acetylcholinesterase. more...

The concentrations of guanidino compounds in human serum and in rabbit serum and brain were determined by cation-exchange chromatography. The total concentration of the guanidino compounds, arginine, taurocyamine, glycocyamine, and guanidinosuccinic acid, was 143 ± 39 nmole/ml in normal human serum (BUN: 7–20 mg/dl), and 296 ± 101 nmole/ml in the serum of an uremic patient (BUN: 40–161 mg/dl). In the latter, the levels of taurocyamine, guanidinosuccinic acid, and methylguanidine were elevated significantly. Rabbits were subjected to bilateral ureteral ligation to produce experimental uremia; 48 hr after ligation (BUN: 90–219 mg/dl), the serum levels of taurocyamine, guanidinosuccinic acid, and methylguanidine had increased significantly, whereas in the brain, levels of taurocyamine and methylguanidine also had increased, and those of glycocyamine and arginine had decreased significantly. more...

Dihydrocodeine was orally administered to mice and the effect of fluid volume on intestinal absorption and acute toxicity was investigated. An increase in fluid volume from 5 to 20 ml/kg resulted in a significant increase in maximum plasma dihydrocodeine concentration (Cmax); the time required to reach Cmax (Tmax) was reduced from 15 to 5 min. However, fluid volume had little effect on the area under the plasma dihydrocodeine concentration-time curve (AUC0→90). The acute toxicity of dihydrocodeine in the initial stage after oral administration increased in proportion to the fluid volume. These results indicate that early acceleration of the gastric emptying rate due to the increase of fluid volume increases the rate, but not the extent, of dihydrocodeine absorption, resulting in the enhancement of acute toxicity. As for thiopental, the influence of fluid volume on intestinal absorption was also examined using [35S]-thiopental. The Cmax value increased and Tmax was reduced from 20 to 5 min by increase of the fluid volume. However, the volume did not influence AUC0→60 values. more...

1. The effect of 20 guanidino compounds was examined individually on the electrical activity of two spontaneously firing giant neurons [periodically oscillating neuron (PON) and tonically autoactive neuron (TAN)] identified in the subesophageal ganglia of the African giant snail, Achatina fulica Ferussac. 2. Guanidinoacetic acid (GAA) at high concentration (10 −4 g/ml) was the only examined compound that showed an inhibitory effect on TAN. No guanidino compound examined had an effect on the PON excitability. more...

Physalaemin, which excites an identifiable mooluscan giant neurone (the TAN, tonically autoactive neurone), lost the effect after the trypsin treatment. Unexpectedly, this peptide shows an inhibitory effect on the same neurone after chymotrypsin treatment. Deamino-dicarba-(d-d-)oxytocin and d-d-Arg-vasotocin, which excite another identifiable neurone (the PON, periodically oscillating neurone) continue to show the effect after chymotrypsin treatment (6 h). But d-d-Arg-vasotocin losts the effect on the PON after trypsin treatment. more...

Conditioned medium (CM) from lectin-stimulated human leukocytes contains factors that induce human promyelocytic cell lines to differentiate along the monocytic pathway. In this report, we show that human promyelocytic cell lines are also induced to differentiate along this pathway by immune interferon (IFN gamma). Various preparations of IFN alpha tested did not induce this differentiation. In cultures containing IFN gamma, the cells are induced to coordinately express monocyte markers and functions such as monocyte-specific surface antigens, HLA-DR antigens, nonspecific esterase, receptors for the Fc fragment of IgG, and the ability to mediate antibody-dependent cell- mediated cytotoxicity. Our data indicate that differentiation induced by IFN gamma is not secondary to an arrest of growth of promyelocytic cell lines, but rather that a proportion of cells is induced along a programmed pathway of terminal differentiation similar to that of normal monocytes. CM contains IFN gamma, but its ability to induce differentiation is greater than expected on the basis of its content of IFN gamma. Treatments at 56 degrees C or at pH 2.0, which abolish IFN gamma activity, abrogate the differentiation ability of CM. The antiviral activity and the differentiation activity contained in the CM are coeluted from gel filtration and reverse-phase columns. Monoclonal antibodies anti-IFN gamma, which completely abrogate the differentiation ability of IFN gamma and the antiviral activity in the CM, completely suppress the induction of some monocyte markers by CM, but only reduce the expression of others. When IFN gamma is added to CM, promyelocytic cell lines are induced to differentiate to a much greater extent than that induced by either IFN gamma or IFN gamma- depleted CM alone. These results show that the differentiation activity of leukocyte CM is due to the synergistic effect of IFN gamma and other factors not yet identified. more...

Taurocyamine, the guanidine analogue of taurine, has been found to occur naturally in various animal tissues. We have analyzed the guanidino compounds in animal brain by a liquid chromatographic method (Mori et al., 1974; Matsumoto et al., 1976a). Table 4.1 shows the distribution of arginine, guanidinosuccinic acid, γ-guanidinobutyric acid, taurocyamine, and guani-dinoacetic acid in bovine brain. While arginine was the major guanidino compound found in bovine brain tissue, measureable quantities of the other guanidine derivatives were also found. The highest concentrations of taurocyamine were found in the cortical gray matter and the lowest in the cerebellum and the medulla oblongata. more...