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Abstract: We report the solution jet beam method as a novel technique to fabricate organic thin films in vacuum. The method can be applied even to ionic organic materials, which cannot be vacuum evaporated due to thermal decomposition. Thin films of RhB (Rhodamine B) and Alq3 (tris(8-hydroxyquinoline)aluminum) were fabricated and characterized. Organic light emitting diodes (OLEDs) were also fabricated using Alq3 films prepared by this method. [Copyright &y& Elsevier]

Co 3d → 2p X-ray emission spectra of LaCoO[sub 3] in the Co 2p photoabsorption region are measured at 40 and 300 K. The spectra mainly reveal features nearly independent of excitation photon energy. This indicates the highly covalent or strongly hybridized nature of the Co 3d state. The emission component showing resonant behavior is also observed. The temperature dependence of the resonant emission confirms that the wave function of Co 3d electrons is totally symmetric in the low-spin ground state and that for the spin state excited thermally through the magnetic transition around 100 K is not. [ABSTRACT FROM AUTHOR]

Ce 4f electronic states in an antiferromagnetic Kondo compound CePd[sub 2]Si[sub 2] and a strong intermediatevalence compound CeNi[sub 2]Si[sub 2] have been investigated by means of high-resolution Ce 4d-4f resonant photoemission spectroscopy at 12 K. The relative intensity of the f[sub 5/2]¹ to f[sub 7/2]¹ final state in the Ce 4f spectrum for CeNi[sub 2]Si[sub 2] is stronger than the relative intensity for CePd[sub 2]Si[sub 2], indicating that the intensity of Kondo resonance scales the Kondo temperature since the Ce 4f spectrum near the Fermi level dominantly reflects the bulk component. Both Ce 4f spectra have been well fitted by the spectral calculations based on a single impurity Anderson model with consideration of the bulk and surface components. Our present calculation indicates that the model is applicable to the analyses of the Ce 4f spectra of the weakly and strongly hybridized systems. [ABSTRACT FROM AUTHOR]

Cholecystokinin (CCK), a known mitogen for the exocrine pancreas, is shown to activate 70-kDa S6 kinase in isolated pancreatic acini. In this study, we examined the kinetics and cellular mechanisms of CCK-induced p70 S6 kinase activation in vivo and in vitro. Fasted mice were intraperitoneally injected with 0.01-10 microg/kg CCK analoge cerulein. Cerulein caused a concentration-dependent activation of p70 S6 kinase, with the maximal effect at 1-10 microg/kg. After 1 microg/kg cerulein administration, the kinase activity was increased at 5 min, peaked at 10 min, and subsequently decreased. Cerulein also caused a rapid and transient activation of Src. Prior administration of the tyrosine kinase inhibitor herbimycin A compeletely inhibited cerulein-induced Src activation, while the inhibition of p70 S6 kinase activity was partial. Similar results were obtained with pancreatic acinar cell line AR42J cells. These results suggest that tyrosine kinases, including Src as a possible candidate, are partly implicated in the signaling pathway of CCK-induced p70 S6 kinase activation in the exocrine pancreas. [ABSTRACT FROM AUTHOR]

In order to clarify the genetic factors in alcohol-related chronic pancreatitis among Japanese, we determined the genotype of two major alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). The restriction fragment-length polymorphisms of the ADH2 and the ALDH2 genes were analyzed in 47 normal subjects and 31 patients with alcoholic pancreatitis. No significant difference between the patient and control groups was found in the ADH2 genotypes. A significant genetic difference between the two groups was found in the ALDH2 locus. The frequency of the ALDH2*1 allele was found to be 0.681 and that of the ALDH2*2 allele was 0.319 in the controls, while these values were 0.935 and 0.065 in the patients, respectively. Most of the patients (27 of 31) were ALDH2*1/2*1, only four were ALDH2*1/2*2, and none of the patients were ALDH2*2/2*2. These results indicate that genetic polymorphism of the ALDH2 gene influences the risk of developing alcoholic pancreatitis in Japanese. [ABSTRACT FROM AUTHOR]

Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene and the 5T genotype of the polythymidine tract at the exon 9 splice branch/acceptor site are shown to be associated with chronic pancreatitis in Caucasian patients. In contrast to Western countries, cystic fibrosis is extremely rare in Japan. In this study, we investigated the association of mutations or polymorphisms of the CFTR gene with chronic pancreatitis in Japanese patients. Forty-seven patients with chronic pancreatitis (alcohol-related in 31, idiopathic in 14, and familial in 2) were examined for the deltaF508 and R117H mutations and polymorphisms of intron 8. DNA was extracted from leukocytes. Mutations and polymorphisms were examined by the allele-specific polymerase chain reactions and confirmed by direct sequencing. None of the patients had deltaF508 or R117H mutations in the CFTR gene. All of 47 healthy Japanese showed the homozygous 7T/7T genotype, whereas the frequencies of 5T, 7T, and 9T alleles were 0.043, 0.894, and 0.064 in the patients, respectively. The difference in allele frequency is statistically significant. Therefore, the present study indicates the association of polymorphism of the polythymidine tract in intron 8 of the CFTR gene with chronic pancreatitis in Japanese patients. [ABSTRACT FROM AUTHOR]