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We have used titania nanoparticles (TiO2) to establish a facile preparation of a highly photoresponsible membrane. An improved photocurrent generator was prepared easily using spin coating of a Nafion/porphyrin/TiO2 mixture on an indium−tin−oxide substrate. Generated photocurrent density was about 10 times higher than that in the absence of TiO2. The resultant electrode shows distinct photocurrent generation despite impediments derived from high dye-concentration (i.e., self-quenching of photoexcited states) and membrane thickness (i.e., losses of electron flow passing through membrane into electrode). Photocurrent densities increased linearly concomitant with high surface concentrations of porphyrin and high membrane thickness. It became evident that TiO2 contributes to more efficient photocurrent generation by intramembrane electron mediation.

Background & Aims: Tumor-suppressor genes found in inherited cancer predisposition syndromes are also responsible for sporadic cancers of the same type. Recently, the tylosis oesophageal cancer (TOC) gene locus has been mapped to 17q25 by linkage analyses of pedigrees with focal nonepidermolytic palmoplantar keratoderma associated with a high risk of esophageal cancer development. The aim of this study was to clarify whether the TOC locus is affected in sporadic esophageal cancers. Methods: We investigated loss of heterozygosity (LOH) on 17q in 58 sporadic esophageal squamous cell carcinomas (ESCs) using 20 microsatellite markers focusing on the TOC locus. Results: LOH on 17q was observed in 37 of 52 (71%) informative cases at one or more loci, 89% (33/37) of which included the TOC locus. The smallest common deleted region was at D17S1839 within the TOC locus. Conclusions: The constructed deletion map revealed that the TOC locus is commonly deleted in sporadic ESCs, suggesting that a tumor-suppressor gene responsible for ESC is contained within this locus. GASTROENTEROLOGY 1998;114:1206-1210

In order to assess the involvement of alpha-1 and alpha-2 adrenoceptors in emesis, the emetic effect of eight alpha agonists was studied in dogs. The i.m. administration of each agonist elicited dose-dependent emesis. The order of potency in inducing emesis was: clonidine greater than oxymetazoline greater than tramazoline greater than naphazoline greater than xylazine greater than epinephrine greater than methoxamine = phenylephrine. The clonidine-induced emesis was antagonized by adrenoceptor antagonists showing alpha-2 blocking activity, yohimbine, tolazoline and phentolamine. Among these antagonists, yohimbine was the most effective. The alpha-1 and beta adrenergic, cholinergic, dopaminergic, histaminergic, serotonergic and opioid receptor antagonists did not prevent the clonidine-induced emesis. The emesis induced by oxymetazoline, tramazoline, xylazine, naphazoline and epinephrine was also antagonized by a selective alpha-2 adrenoceptor antagonist, yohimbine, but not by a selective alpha-1 adrenoceptor antagonist, prazosin. In contrast, methoxamine and phenylephrine-induced emesis was antagonized by prazosin, but not by yohimbine. Neither yohimbine nor prazosin prevented the morphine- and histamine-induced emesis. These results indicate that alpha-2 adrenoceptors are involved in the mediation of emetic action, and that the alpha adrenoceptor-mediated emesis does not involve beta adrenergic, cholinergic, dopaminergic, histaminergic, serotonergic and opioid receptors in the emetic pathway. This study further suggests that alpha adrenoceptors involved in the emesis are mainly of the alpha-2 type, although the involvement of alpha-1 adrenoceptors cannot be ruled out.

The composition dependence of the phase-separated structures in the polymer mixtures consisting of a thermotropic liquid crystalline (LC) copolyester (X-7G) and poly(ethylene terephthalate) (PET) was investigated by means of polarized light microscopy. For this purpose the mixtures were solution-cast into thin films, followed by isothermal annealing at 270 °C. Although the final structure was the LC droplets dispersed in the isotropic matrix for all mixtures, a variety of pattern-forming processes were observed, depending on the composition. For the mixtures with higher X-7G content, dewetting of the X-7G component on the surface of the glass substrate played an important role in the pattern formation.

A number of studies have been made on cornerability during braking, and it is known that the degree of yaw rate change reaches a peak at a certain value of braking decleration. In this paper, a theoretical analysis is carried out on the mechanism generating this peak. It was found that providing the proper roll steer and compliance steer characteristics of the rear suspension is an effective means of lowering this peak value.

The lateral stiffness of radial tyre sidewalls was analysed by using the netting theory, which is based on the assumption that the carcass cord is inextensible. The additional rubber stiffness due to the stretching rigidity in the circumferential direction and the bending stiffness of the sidewall were evaluated by the energy method. Then the effect of lowering the aspect ratio on the lateral stiffness of radial tyres was elucidated by this analysis. Good agreement was obtained between the analytical and experimental results.