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We used molecular dynamics simulations to investigate the effect of disorder of the hydroxylated amorphous silica surface on the structure of 8 nm IL films formed from two ionic liquids featuring the same cation 1-butyl-3-methyl-imidazolium or [BMIM], paired with bis(trifluoromethanesulphonyl)amide [NTF2] and tetrafluoroborate [BF4] anions. Several silica surfaces were modelled to estimate the effect of their atomic-scale configuration on the solid-liquid interface and the results are compared to those simulated on the crystalline cristobalite surface. Using strongly polar surfaces, we could also evaluate the response of the ILs to the electric field externally controlled or generated by charged defects in the silica film. We found that the structure of the liquids becomes weaker away from the interface and more susceptible to electric field. Our simulations show that [BMIM][BF4] has a large intrinsic dipole originating at the interface, resilient to external fields, while the polarisation of [BMIM][NTF2] can be more easily controlled.

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We report two cases of prostatic cancer invading the rectum with circumferential rectal wall thickening. In both cases, reddish and uneven edematous mucosa was observed by colonoscopy and the boundary of the lesion was indistinct. No mass or ulcer formation was not observed. CT scan showed irregular prostatic swelling and circumferential rectal wall thickening adjacent to the prostate. The rectal biopsy specimen showed moderately to poorly differentiated adenocarcinoma, and it was positive on PSA immunostaining. Although rectal invasion of prostatic cancer is relatively rare, it is important to be aware that prostatic cancer can cause circumferential stenosis of the rectum.

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We report a case of a 64-year-old Japanese man with adenoid cystic carcinoma. An elevated lesion covered by intact epithelium in the thoracic esophagus was found in September, 2007 and been followed. After dysphagia appeared follow-up endoscopy was performed in January, 2010, and morphological change into a protruding tumor was recognized. Since adenoid cystic carcinoma was detected by endoscopic biopsy, the patient underwent esophageal resection. The resected specimen showed a cribriform pattern and a certain amount of mucous substance which was positive for Alcian blue, within a solid nest. The tumor cells were positive for S-100 protein and negative for αSMA, so the tumor was diagnosed as an adenoid cystic carcinoma.

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We report the case of a 15-year-old Japanese boy with eosinophilic gastroenteritis. The patient complained of abdominal pain and watery diarrhea and had a history of allergic rhinitis. Laboratory data on admission showed leukocytosis with remarkable eosinophilia. Microscopic examination of the biopsied specimens taken from the esophagus, stomach, duodenum, lower ileum and colon showed eosinophilic infiltration. Especially in the lower esophagus, there was a ring-like discoloration with remarkable eosinophil infiltration. We diagnosed eosinophilic gastroenteritis and his clinical symptoms and eosinophilia improved following starting corticosteroid therapy. After 5 months therapy with prednisolone, discoloration of upper digestive tract disappeared. There have been no reports describing discoloration in the lower end of the esophagus seen by gastroscopy.

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Indole is most commonly known as a diagnostic marker and a malodorous chemorepellent. More recently, it has been recognized that indole also functions as an extracellular signaling molecule that controls bacterial physiology and virulence. The gene (tnaA) for tryptophanase, which produces indole, ammonia, and pyruvate via ß-elimination of L-tryptophan, was cloned from Prevotella intermedia ATCC 25611 and recombinant TnaA was purified and enzymatically characterized. Analysis by reverse transcriptase-mediated PCR showed that the gene was not cotranscribed with flanking genes in P. intermedia. The results of gel-filtration chromatography suggested that P. intermedia TnaA forms homodimers, unlike other reported TnaA proteins. Recombinant TnaA exhibited a K(m) of 0.23 ± 0.01 mM and k(cat) of 0.45 ± 0.01 s(-1). Of 22 Prevotella species tested, detectable levels of indole were present in the culture supernatants of six, including P. intermedia. Southern hybridization showed that tnaA-positive signals were present in the genomic DNA from the six indole-producing strains, but not the other 16 strains tested. The indole-producing strains, with the exception of Prevotella micans, formed a phylogenetic cluster based on trees constructed using 16S rRNA gene sequences, which suggested that tnaA in P. micans might have been transferred from other Prevotella species relatively recently.

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The l-tryptophan degradation product indole is a purported extracellular signaling molecule that influences biofilm formation in various bacteria. Here we analyzed the mechanisms of indole production in Fusobacterium nucleatum and the effects of tryptophan and indole on F. nucleatum planktonic and biofilm cells. The amino acid sequence deduced from the fn1943 gene in F. nucleatum ATCC 25586 was 28% identical to that deduced from tnaA in Escherichia coli, which encodes tryptophanase catalyzing the beta-elimination of l-tryptophan to produce indole. The fn1943 gene was cotranscribed with the downstream gene fn1944, which is a homolog of tnaB encoding low-affinity tryptophan permease. The transcript started at position -68 or -153 from the first nucleotide of the fn1943 translation initiation codon. Real-time quantitative PCR showed that much more F. nucleatum fn1943 transcripts were obtained from log-phase cells than from stationary-phase cells. Indole production by the purified recombinant protein encoded by fn1943 was examined using high-performance liquid chromatography. The K(m) and k(cat) of the enzyme were 0.26 +/- 0.03 mM and 0.74 +/- 0.04 s(-1), respectively. F. nucleatum biofilm formation and the biofilm supernatant concentration of indole increased dose dependently with increasing tryptophan concentrations. Exogenous indole also increased F. nucleatum biofilm formation in a dose-dependent manner. Even at very high concentrations, tryptophan did not affect fn1943 expression, whereas similar indole concentrations decreased expression. Thus, exogenous tryptophan and indole were suggested to increase F. nucleatum biofilms.

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