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Although the action of cetirizine dihydrochloride (cetirizine), a potent histamine H1 receptor antagonist, has been well known, its effect on the cytokine profiles in the nasal immune inductive site has not been elucidated yet. We studied the effect of cetirizine on the cytokine profiles in the nasal-associated lymphoid tissue (NALT), which is a principal mucosal lymphoid tissue of the respiratory tract in rodents. Two different doses of cetirizine were given intraorally for 5 days before the nasal challenge of ovalbumin in sensitized mice. The sensitized group was given normal saline instead of cetirizine, and the nonsensitized group had no sensitization or medication. The cytokine gene expressions in the NALT taken from the mice were investigated with real-time quantitative reverse-transcription polymerase chain reaction. The effect of cetirizine on the allergic symptom score, histamine threshold, and the eosinophil count in the nasal septal mucosa were examined also. Compared with the normal mice, the sensitized mice showed significantly increased levels of interleukin (IL)-4 and IL-5 gene expression although the increase of interferon (INF)-γ gene expression was not significant. In the cetirizine groups, the levels of expression of IL-4, IL-5, and INF-γ in the NALT were significantly decreased compared with the sensitized group. The cetirizine groups also showed decreased allergic symptom score, histamine threshold, and eosinophil count in the nasal septal mucosa compared with the sensitized group. In conclusion, cetirizine reduced the levels of expression of IL-4, IL-5, and INF-γ in the NALT of ovalbumin-sensitized mice. Cetirizine also reduced the acute allergic symptom, histamine sensitivity, and eosinophil count in the nasal septal mucosa.

Conformation change occurring during the formation of the liquid crystalline phase was investigated by using the in situ Fourier transform infrared spectroscopy. An isotropic glass of a random liquid crystalline copolyester consisting of 60 mol% p-hydroxybenzoic acid/40 mol% ethylene terephthalate was prepared with the cast from a solution and was heated from the room temperature up to 300°C. The onset of the transformation from the gauche conformers to the trans conformers of the ethylene glycol group was observed at ca. 60°C. The change in packing was indicated by the change in the intensity of the bands assignable to the aromatic rings around 150°C. Liquid crystalline phase formation observed with the optical method started to occur at ca. 200°C in association with the loss of the packing.

A kinetics of the orientation of a commercial liquid crystalline copolyester (60 mol% p-hydroxybenzoic acid/40 mol% ethylene terephthalate) in the magnetic field (6 T) was studied by means of X-ray measurements. The data were analyzed in terms of the domain model and the lattice model simulation. The rates of the magnetic orientation from an initial random state of orientation were found to be of 10−4 to 10−2 s−1 depending on temperatures. The comparison of the results obtained by the domain model and by the simulation suggested that the inter-domain interaction is important to explain the experimental result obtained for the reorientation process.

The melt crystallization process of isotactic polystyrene (i-PS) was studied by means of in situ Fourier transform infrared (FTIR) spectroscopy, with a focus on the conformational changes during the induction period. The spectra obtained during the induction period suggested the occurrence of some ordered structure that is characterized by higher regularity and packing of the helical moieties than observed in the melt. This ordered structure was clearly different from the amorphous structure, and close to the crystal structure. The Avrami analysis indicated that the formation process of the ordered structure at the late stage of the induction period is similar to the growth process of the crystallites after the induction period.

A thermotropic liquid crystalline copolyester, one from the Rodrun series, consisting of 60 mol % p-hydroxybenzoic acid and 40 mol % ethylene terephthalate was aligned under a magnetic field of 6 T...

Magnetic orientation of isotactic polystyrene during the isothermal crystallization at 210 °C in the magnetic field of 6 T is studied by using the magnetic birefringence, X-ray diffraction, and infrared measurements. The orientation starts in the vicinity of the end of the induction period, that is, before the crystal growth is observed by the wide angle X-ray diffraction This suggests that some anisotropic structures formed in the induction period are responsible for the magnetic orientation. Crystals formed are aligned with the c-axis, perpendicular to the magnetic field. Crystallization process is accelerted under the magnetic field.

Fluorescence lifetimes (τF) of acridine have been measured in water–alcohol solvent mixtures at room temperature. The τF of acridine in pure water (11.5 ± 0.1 ns) was drastically decreased upon the addition of small amounts of alcohol; i.e.τF= 1.2 ± 0.01 ns in 0.5 mole fraction of ethanol in water and τF= 0.4 ± 0.01 ns in pure ethanol. The extent of the decrease in τF becomes more evident in the following order: methanol < ethanol < propan-1-ol. This is the order of increasing hydrophobic interaction between alcohols and acridine, suggesting that alcohol molecules preferentially solvate acridine in water. Such an observation has been discussed in terms of the degree of preferential solvation.

芳香族高分子のβ緩和の機構を明らかにするため, ポリエチレン-1, 2-ジフェノキシエタン-p, p″-ジカルボキシレート (PEBC) の誘電的β緩和を測定した. PEBCはポリエチレンテレフタレート (PET) に相当するエステル部分を持つ, 芳香族エステルエーテルコポリマーである. PEBCのスペクトルからPETのスペクトルを差し引くことにより得られた差スペクトルは, 損失極大周波数がPETよりも高く, さらに見かけの活性化エネルギーはPETより小さかった. これらのことから, 差スペクトルはPEBCのエーテル部分に起因していると考えられる. っまり, PEBCのβ緩和はエステル基とエーテル基を含む部分の二っの緩和の和で表されることを示している. これは, 芳香族ポリエステルのβ分散に起因する分子運動が, 芳香環に挟まれた屈曲性の高い分子鎖部分の運動であるという先の報告を支持するものである.

Thermal Expansion of a 60 mol% para -Hydroxybenzoic Acid/40 mol% Ethylene Terephthalate Liquid Crystalline Copolyester Oriented in a Magnetic Field

Background: Peroxisome proliferator-activated receptor-γ (PPARγ) is a member of the nuclear receptors, which regulate fatty acid metabolites. One of the natural ligands for PPARγ is 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2), a major metabolite of prostaglandin D2 (PGD2). Recently, PPARγ has been shown to play an important role in anti-inflammatory reactions, including within-airway allergic diseases, in a mouse model. Our aim was to clarify the expression and localization of PPARγ and PGD2 synthase, which produces ligands of PPARγ, in nasal polyps by immunohistochemical analysis. Methods: Nasal polyps of chronic rhinosinusitis patients (6 asthmatic patients and 6 nonasthmatic patients) were obtained during surgery. May-Grünwald-Giemsa staining was performed to evaluate the eosinophil infiltration of the polyps. To identify the cells expressing PPARγ protein and PGD2 synthase, double immunostaining was performed using anti-PPARγ antibody, monoclonal antileukocyte antibodies, and PGD2 synthase antibody. Results: The number of eosinophils and the number of PPARγ-positive cells in the nasal polyps of the asthmatic patients were significantly higher than those in the nonasthmatic patients. PPARγ was expressed on eosinophils and T cells of the infiltrating cells in the nasal polyps. PGD2 synthase was also expressed on PPARγ-positive cells. Conclusion: PPARγ is involved in nasal polyposis pathogenesis, acting on eosinophils and T cells.

When representative coals were suspended in tetrahydrofuran (THF), ultraviolet (UV) light irradiation of the slurries yielded an increased rate of extraction for most coals. Some subbituminous coals were insensitive to photochemical extraction. Removal of the extract and refreshment of the solvent increased the photochemical extraction yield in comparison with continuous irradiation while the extract accumulated in the solvent. Extraction yields by weight for the photochemical process are compared with the corresponding dark extraction yields and are found to be up to 5 times greater

The dielectric β-relaxation in poly(ethylene terephthalate) and ethylene isophthalate terephthalate copolyesters with various ethylene isophthalate contents was investigated over a wide range of frequencies. Isothermal spectra and normalized plots show that the dielectric β-relaxation is characterized by the molecular structure between the aromatic rings. The equilibrium polarizability of the motional segment, which was estimated from the dielectric increment obtained by the best fit of the Havriliak-Negami equation to the Cole-Cole plot, indicates that torsional vibrations of the main chain are correlated over a length corresponding to one monomer.

Magnetic -field induced orientation of crystalline polymers recently reported by our group is briefly summarized and a possible application of this new phenomenon is presented. We have recently reported a new finding that crystalline polymers including poly(ethylene-2,6-naphthalate), isotactic polystyrene, isotactic polypropylene, poly(ethylene terephthalate), and paraffin align under a strong magnetic field during the phase transition from melt to crystal. We have assumed that some ordered structure, most likely liquid-crystalline-like structure, appearing transiently during the transition is responsible for this phenomenon. Aligned films were transparent and exhibited retardation of several hundred nanometers, suggesting a possible application to fabrication of materials demanded for optical use.

Magnetic -field induced orientation of crystalline polymers recently reported by our group is briefly summarized and a possible application of this new phenomenon is presented. We have recently reported a new finding that crystalline polymers including poly(ethylene-2,6-naphthalate), isotactic polystyrene, isotactic polypropylene, poly(ethylene terephthalate), and paraffin align under a strong magnetic field during the phase transition from melt to crystal. We have assumed that some ordered structure, most likely liquid-crystalline-like structure, appearing transiently during the transition is responsible for this phenomenon. Aligned films were transparent and exhibited retardation of several hundred nanometers, suggesting a possible application to fabrication of materials demanded for optical use.

The effect of drawing on the glass-transition temperature of amorphous poly(ethylene terephthalate) has been studied. The Tg decreases to a minimum at a draw ratio of 1.5, then increases to a maximum at a draw ratio of about 2.0, and again decreases with increasing draw ratio. The relationship between the change of structure and Tg is discussed in terms of the configurational entropy and the rate of molecular motion in local-mode relaxation. On the basis of configurational entropy, the decrease of Tg at the beginning of drawing depends on the increase of configurational entropy, while at draw ratios above 2.0 it depends on the increase of entropy associated with intermolecular interaction. From the point of view of molecular motion, it is concluded that the change of Tg is determined by local oscillations in the amorphous region.

In previous articles, we reported the change in physical properties of hydrophobic polymers caused by absorption of a very small amount of water. This article describes the changes in physical properties of three polyesters owing to absorption of water. The tested polymers were poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT), and polyethylene 2,6-naphthalate (PEN). PBT has more flexible main chains than that of PET, and PEN has more rigid main chains. The dielectric measurements revealed that water absorption results in shortening the relaxation time for PET, while the relaxation time for moist PBT becomes longer. The larger amount of absorbed water yields the higher density of PET and the lower density of PBT. The water absorption of the polyesters also yields increments in dielectric constants and relaxation strength. Distribution of relaxation time of the polyesters is narrowed by absorption of water.

Many papers have reported on the thermal shrinkage mechanism of drawn polymers. The cause of the thermal shrinkage is very complex, because that relates to many factors. In this study, atactic polystyrene, a noncrystalline polymer, was used to eliminate factors related to the melting and crystallization effects, and it is considered that there is a relation between the change of the polymer's structure due to heat treatment and thermal shrinkage. It is observed in a certain temperature range that the thermal shrinkage of drawn polystyrene is not caused by increase of the entropy but results in decrease of the entropy.

This study was undertaken to elucidate the state of a polymer in the amorphous state through a change of motion of the molecular chain caused by heat treatment below the glass transition temperature. From dielectric measurements of amorphous poly(ethylene terephthalate) heat-treated below T g , it was found that the average relaxation time, the distribution of relaxation time and the dielectric strength increase with increase of heat treatment. From these results, it was concluded that the amorphous state becomes more random by heat treatment.

Background Peroxisome proliferator-activated receptor γ (PPAR-γ) has been shown to play an important role in the control of inflammatory responses acting on macrophages, mast cells, T cells, and eosinophils. The present study was aimed at investigating the effects of PPAR-γ agonist on nasal symptoms and eosinophil accumulations in nasal mucosa by using a murine allergic rhinitis model. Furthermore, we examined the expression of PPAR-γ in the nasal mucosa in mice. Methods BALB/c mice were sensitized and challenged intranasally with ovalbumin. Ciglitazone, a PPAR-γ agonist, was administered orally 6 hours before each nasal challenge. Results Administration of PPAR-γ agonist significantly decreased the number of nasal rubs, nasal histamine responsiveness, serum IgE, IL-5 production from the spleen, and eosinophilic infiltration in the nasal mucosa. Furthermore, PPAR-γ was expressed in eosinophils and epithelial cells in the nasal mucosa by immunohistochemistry. Conclusions PPAR-γ was expressed in eosinophils and epithelial cells in the nasal mucosa. Also, the oral administration of ciglitazone is effective in upper airway allergic inflammation in mice.

The purpose of this study is to clarify the role of peptide leukotrienes(LTs) on the onset of characteristic hyperreactive nasal symptoms of nasal allergy by observing the time course of the correlation among degrees of nasal symtoms, and by observing the amount of chemical mediators and the number of inflammatory cells in the nasal lavage fluid after nasal antigen challenge in subjects with Japanese cedar pollinosis during off season. Sneezing was terminated within 10 minutes and nasal discharge within 2 hours. However, time course change of the percent increase of nasal airway resistance showed dual response consisting of immediate and late phase responses. The peak of the former was seen at 30 minutes and the latter was at 7 hours after provocation. The significant increase of eosinophils in the nasal lavage fluid was observed during both the immediate and the late phase responses, but during the late phase response, the increase was more prominent. Basophilic cells definitely increased during the late phase response. The amount of LTs in the nasal lavage fluid increased significantly during both the immediate and the late phase responses. In contrast, the level of histamine increased significantly only during the immediate phase response.Considering that LTs, especially LTD, , has potent and persistent effect on causing swelling of nasal mucosa, LTs may play important role in causing nasal obstruction during both the immediate and the late phase responses after antigen challenge. On the other hand, the role of histamine may be confined to cause the hyperreactive nasal symptoms during the immediate phase response. Our results also indicate that the source of LTs in the nasal lavage fluid during the immediate phase response is mast cells in nasal mucosa, and during the late phase response, eosinophils and basophils are important as the source of LTs in addition to mast cells.