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Malignant peritoneal mesothelioma (MPM) is a rare malignant tumor with peritoneal thickening. Tuberculous peritonitis also shows peritoneal thickening, so differentiating between the two is important but difficult if latent tuberculosis infection (LTBI) is present. We herein report a patient with MPM and LTBI. A 79-year-old man was diagnosed with peritoneal thickening on computed tomography. Interferon gamma release assay (IGRA) results were positive, suggesting tuberculous peritonitis. He underwent a laparoscopic omental biopsy and was diagnosed with MPM, which can occur together with LTBI. If peritoneal thickening is observed, an IGRA should be performed early, and the possibility of LTBI should be considered.

Background and aim Because the risk of colorectal cancer has not been well examined in fecal immunochemistry test (FIT)-positive patients who previously underwent colonoscopy, this study aimed to investigate this topic. Methods This was a single-center, observational study of prospectively collected data in Japan. FIT-positive, average-risk patients who underwent colonoscopy were divided into groups as follows: those who never underwent colonoscopy in the past (no colonoscopy group), those with a history of colonoscopy between 6 months and 5 years (0.5- to 5-year colonoscopy group), and those with a history of colonoscopy more than 5 years ago (> 5-year colonoscopy group). We investigated the prevalence of advanced neoplasia and invasive cancer among these groups using multiple logistic regression analysis. Results Detection rates of advanced neoplasia in the no colonoscopy group, 0.5- to 5-year colonoscopy group, and > 5-year colonoscopy group were 14.8% (240/1626), 3.9% (13/330), and 6.9% (17/248), respectively. Detection rates of invasive cancer in each aforementioned group were 5.7% (92/1,626), 0.3% (1/330), and 1.2% (3/248), respectively. Odds ratios of advanced neoplasia in the 0.5- to 5-year colonoscopy group and > 5-year colonoscopy were 0.23 (95% confidence interval [CI]: 0.13-0.42) and 0.40 (95% CI: 0.24-0.68), respectively, in multivariate analysis. The odds ratios of invasive cancer in each aforementioned group were 0.05 (95% CI: 0.01-0.37) and 0.19 (95% CI: 0.06-0.61), respectively. Conclusion Re-screening with the FIT should not be recommended for at least 5 years for average-risk patients after colonoscopy without high-risk neoplasms, because the risks of colorectal cancer are low in such patients.

In clinical trials, acotiamide hydrochloride (acotiamide: Z-338) has been reported to be useful in the treatment of functional dyspepsia. Here, we investigated the effects of acotiamide on gastric contraction and emptying activities in rats in comparison with itopride hydrochloride (itopride) and mosapride citrate (mosapride). We also examined in vitro the compound's inhibitory effect on acetylcholinesterase (AChE) activity derived from rat stomach. In in vivo studies, acotiamide (30 and 100mg/kg s.c.) and itopride (100mg/kg s.c.) markedly enhanced normal gastric antral motility in rats. In gastric motility dysfunction models, acotiamide (100mg/kg s.c.) and itopride (100mg/kg s.c.) improved both gastric antral hypomotility and the delayed gastric emptying induced by clonidine, an α(2)-adrenoceptor agonist. In contrast, mosapride (10mg/kg s.c.) had no effect on these models. Like the AChE inhibitors itopride (30 mg/kg s.c.) and neostigmine (10 μg/kg s.c.), acotiamide (10mg/kg s.c.) also clearly enhanced gastric body contractions induced by electrical stimulation of the vagus, which were abolished by atropine and hexamethonium, whereas mosapride (3 and 10mg/kg s.c.) did not. In in vitro studies, acotiamide concentration-dependently inhibited rat stomach-derived AChE activity (IC(50)=2.3 μmol/l). In addition, stomach tissue concentrations of acotiamide after administration at 10mg/kg s.c. were sufficient to produce inhibition of AChE activity in rat stomach. These results suggest that acotiamide stimulates gastric motility and improves gastric motility dysfunction in rats by inhibiting AChE activity, and may suggest a role for acotiamide in improving gastric motility dysfunction in patients with functional dyspepsia.

Fully modified 4'-thioDNA, an oligonucleotide only comprising 2'-deoxy-4'-thionucleosides, exhibited resistance to an endonuclease, in addition to preferable hybridization with RNA. Therefore, 4'-thioDNA is promising for application as a functional oligonucleotide. Fully modified 4'-thioDNA was found to behave like an RNA molecule, but no details of its structure beyond the results of circular dichroism analysis are available. Here, we have determined the structure of fully modified 4'-thioDNA with the sequence of d(CGCGAATTCGCG) by NMR. Most sugars take on the C3'-endo conformation. The major groove is narrow and deep, while the minor groove is wide and shallow. Thus, fully modified 4'-thioDNA takes on the A-form characteristic of RNA, both locally and globally. The only structure reported for 4'-thioDNA showed that partially modified 4'-thioDNA that contained some 2'-deoxy-4'-thionucleosides took on the B-form in the crystalline form. We have determined the structure of 4'-thioDNA in solution for the first time, and demonstrated unexpected differences between the two structures. The origin of the formation of the A-form is discussed. The remarkable biochemical properties reported for fully modified 4'-thioDNA, including nuclease-resistance, are rationalized in the light of the elucidated structure.

The synthesis and properties of fully modified 4'-thioDNAs, oligonucleotides consisting of 2'-deoxy-4'-thionucleosides, were examined. In addition to the known literature properties (preferable hybridization with RNA and resistance to endonuclease hydrolysis), we also observed higher resistance of 4'-thioDNA to 3'-exonuclease cleavage. Furthermore, we found that fully modified 4'-thioDNAs behaved like RNA molecules in their hybridization properties and structural aspect, at least in the case of the 4'-thioDNA duplex. This observation was confirmed by experiments using groove binders, in which a 4'-thioDNA duplex interacts with an RNA major groove binder, lividomycin A, but not with DNA groove binders, to give an increase in its thermal stability. Since a 4'-thioDNA duplex competitively inhibited the hydrolysis of an RNA duplex by RNase V1, it was not only the physical properties but also this biological data suggested that a 4'-thioDNA duplex has an RNA-like structure.

The hepatoprotective effect of ZNC-2381 (1-(4-aminophenyl) methyl-3-(3-nitrophenyl)-1,3-dihydroimidazo[4,5-b]pyridine-2-one), a novel 2-one dihydroimidazopyridine derivative, has been evaluated in several experimental models of hepatic injury. In mice, oral ZNC-2381, administered at doses of 3, 10 or 30 mg kg−1, 1 h before induction of hepatic injury with concanavalin A, dose-dependently inhibited increases in serum alanine aminotransferase (ALT) activity. Apoptosis of liver cells, as indicated by DNA fragmentation (nucleosome assay) and DNA-ladder formation (electrophoresis), was also inhibited dose-dependently. ZNC-2381 dose-dependently inhibited concanavalin A-induced increases in serum tumour necrosis factor (TNF)-α levels, and TNF-α mRNA expression in the liver. Oral ZNC-2381 also dose-dependently inhibited increases in serum ALT activity in mice with hepatic injury induced by Propionibacterium acnes and a bacterial lipopolysaccharide (LPS) or d-galactosamine-LPS, and in rats with d-galactosamine-induced hepatic injury. These results indicate that oral ZNC-2381 inhibits cytokine (TNF-α) production and cytokine-related hepatocellular apoptosis, and might thus prevent different types of hepatic injury.

We report herein a practical synthesis of 4'-thiothymidine (15) and appropriately protected 2'-deoxy-4'-thiocytidine (16), -thioadenosine (27), and -thioguanosine (29) derivatives, substrates for the synthesis of 4'-thioDNA, from the corresponding 4'-thioribonucleosides. 2'-deoxy-4'-thiopyrimidine nucleosides were synthesized using a radical reaction of the corresponding 2'-alpha-bromo derivatives, which were prepared via 2,2'-O-anhydro derivatives. 2'-deoxy-4'-thiopurine nucleosides were synthesized using the same radical reaction of the corresponding 2'-beta-bromo derivatives.