A rhenium complex, [ReBr(CO)3(thf)]2, catalyzed reactions of aromatic ketimines with aldehydes to give isobenzofuran derivatives in good to excellent yields. In contrast to ruthenium and rhodium catalysts, aldehydes, which are polar unsaturated molecules, inserted into the C-H bond after activation by the rhenium complex.

AimsElobixibat is a minimally absorbed ileal bile acid transporter inhibitor. This study aimed to investigate the safety, tolerability, efficacy, pharmacokinetics and pharmacodynamics of elobixibat in Japanese patients with chronic constipation.MethodsThis study consisted of single‐dose and multiple‐dose tests with a dose‐escalating design. Sixty patients including females and males were randomized into five dose levels of elobixibat (2.5, 5, 10, 15 or 20 mg, n = 10 per level) and corresponding placebo (n = 2 per group). A crossover design was used to examine food effect in single‐dose test. Patients received test tablets once daily for 14 days in multiple‐dose test. We assessed pharmacokinetic‐dose proportionality, levels of serum high‐ and low‐density lipoprotein cholesterol and plasma 7α‐hydroxy‐4‐cholesten‐3‐one (C4), food effect and sex‐specific effect. Adverse events and bowel functions such as bowel movements, stool consistency and straining were also evaluated.ResultsFood consumption reduced systemic exposure by around 80% [e.g. least squares mean (ratio of breakfast/no breakfast) maximum plasma concentration: 0.2085 (90% confidence interval, 0.1371–0.3172) at 15 mg] while increased plasma C4 level (P < 0.001). In the multiple‐dose test, elobixibat reduced low‐density lipoprotein cholesterol and increased C4 whilst unaltering high‐density lipoprotein cholesterol level. The increased spontaneous bowel movement frequency was correlated with higher dosage and higher C4 level (R2 = 0.5929 at Week 2). Adverse events were mainly gastrointestinal symptoms, most of which were mild.ConclusionsElobixibat should be taken before breakfast. Once‐daily administration of elobixibat was found to be safe and tolerated up to 20 mg in female and male patients with chronic constipation.

BackgroundIt has been reported that low-viscous and fermentable dietary fiber and nondigestible oligosaccharides enhance mineral absorption. Resistant maltodextrin, nonviscous, fermentable and soluble source of dietary fiber, has several physiological functions. However, influence of resistant maltodextrin on mineral absorption is unclear.Aim of the studyWe conducted balance studies in rats to investigate effects of resistant maltodextrin and hydrogenated resistant maltodextrin on apparent mineral absorption.MethodsIn experiment 1 (Exp. 1), 40 rats were fed test diets based on AIN-93G with or without resistant maltodextrin or hydrogenated resistant maltodextrin for 2 weeks. In experiment 2 (Exp. 2), 32 rats were cecectomized (CX) or sham-operated (Sham) and fed diets with or without hydrogenated resistant maltodextrin for 1 week.ResultsIn Exp. 1, ingestion of resistant maltodextrin and hydrogenated resistant maltodextrin dose-dependently enhanced apparent absorption rates of Ca, Mg, Fe and Zn, and increased cecal fermentation with cecal expansion. In Exp. 2, the absorption rates of Ca and Mg were significantly enhanced by ingestion of hydrogenated resistant maltodextrin in Sham group but not in CX group. The promotion of Fe and Zn absorption was not affected by cecectomy.ConclusionIngestion of resistant maltodextrin and hydrogenated resistant maltodextrin increased apparent Ca and Mg absorptions dependent on cecal fermentation, while other mechanisms may also be involved in promotion of apparent Fe and Zn absorption by resistant maltodextrin.

Faithful replication of chromosomes is crucial to genome integrity. In yeast, the ORC binds replication origins throughout the cell cycle. However, Cdc45 binds these before S-phase, and, during replication, it moves along the DNA with MCM helicase. When replication progression is inhibited, checkpoint regulation is believed to stabilize the replication fork; the detailed mechanism, however, remains unclear. To examine the relationship between replication initiation and elongation defects and the response to replication elongation block, we used fission yeast mutants of Orc1 and Cdc45-orp1-4 and sna41-928, respectively-at their respective semipermissive temperatures with regard to BrdU incorporation. Both orp1 and sna41 cells exhibited HU hypersensitivity in the absence of Chk1, a DNA damage checkpoint kinase, and were defective in full activation of Cds1, a replication checkpoint kinase, indicating that normal replication is required for Cds1 activation. Mrc1 is required to activate Cds1 and prevent the replication machinery from uncoupling from DNA synthesis. We observed that, while either the orp1 or the sna41 mutation partially suppressed HU sensitivity of cds1 cells, sna41 specifically suppressed that of mrc1 cells. Interestingly, sna41 alleviated the defect in recovery from HU arrest without increasing Cds1 activity. In addition to sna41, specific mutations of MCM suppressed the HU sensitivity of mrc1 cells. Thus, during elongation, Mrc1 may negatively regulate Cdc45 and MCM helicase to render stalled forks capable of resuming replication.

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