The RNA ligands for mouse proline-rich RNA-binding protein (mouse Prrp) contain two consensus sequences in separate loop structure

Mouse proline-rich RNA-binding protein (mPrrp) is a mouse ortholog of Xenopus Prrp, which binds to a vegetal localization element (VLE) in the 3′-untranslated region (3′-UTR) of Vg1 mRNA and is expected to be involved in the transport and/or localization of Vg1 mRNA to the vegetal cortex of oocytes. In mouse testis, mPrrp protein is abundantly expressed in the nuclei of pachytene spermatocytes and round spermatids, and shifts to the cytoplasm in elongating spermatids. To gain an insight into the function of mPrrp in male germ cells, we performed in vitro RNA selection (SELEX) to determine the RNA ligand sequence of mPrrp. This analysis revealed that many of the selected clones contained both of two conserved elements, AAAUAG and GU(1–3)AG. RNA-binding study on deletion mutants and secondary structure analyses of the selected RNA revealed that a two-loop structure containing the conserved elements is required for high-affinity binding to mPrrp. Furthermore, we found that the target mRNAs of Xenopus Prrp contain intact AAAUAG and GU(1–3)AG sequences in the 3′-UTR, suggesting that these binding sequences are shared by Prrps of Xenopus and mouse

Engineered Corynebacterium glutamicum as an endotoxin-free platform strain for lactate-based polyester production

The first biosynthetic system for lactate (LA)-based polyesters was previously created in recombinant Escherichia coli (Taguchi et al. 2008). Here, we have begun efforts to upgrade the prototype polymer production system to a practical stage by using metabolically engineered Gram-positive bacterium Corynebacterium glutamicum as an endotoxin-free platform. We designed metabolic pathways in C. glutamicum to generate monomer substrates, lactyl-CoA (LA-CoA), and 3-hydroxybutyryl-CoA (3HB-CoA), for the copolymerization catalyzed by the LA-polymerizing enzyme (LPE). LA-CoA was synthesized by D-lactate dehydrogenase and propionyl-CoA transferase, while 3HB-CoA was supplied by β-ketothiolase (PhaA) and NADPH-dependent acetoacetyl-CoA reductase (PhaB). The functional expression of these enzymes led to a production of P(LA-co-3HB) with high LA fractions (96.8 mol%). The omission of PhaA and PhaB from this pathway led to a further increase in LA fraction up to 99.3 mol%. The newly engineered C. glutamicum potentially serves as a food-grade and biomedically applicable platform for the production of poly(lactic acid)-like polyester

Acute Small Bowel Perforation Caused by Obstruction of a Novel Tag-Less AgileTM Patency Capsule

A 74-year-old man visited our hospital complaining of abdominal pain. An abdominal computed tomography scan showed multiple wall thickness of the small bowel. Capsule endoscopy was recommended for further evaluation, and patency capsule examination was performed. Eighteen hours after patency capsule ingestion, he experienced small bowel perforation with severe peritonitis caused by intestinal pressure rising because of the patency capsule trapped in his terminal ileum. An ileocolic resection was performed, including the removal of the sclerotic ileum as an emergency surgery. A pathological examination showed transmural inflammation and multiple ulcers with perforation of the small intestine, consistent with Crohn’s disease. Here, we report a rare and valuable case of novel tag-less AgileTM patency capsule (Given Imaging Ltd., Yoqneam, Israel) retention leading to small bowel perforation

Picosecond pulse radiolysis: Dynamics of solvated electrons in ionic liquid and geminate ion recombination in liquid alkanes

金沢大学理工研究域自然システム学系A picosecond pulse radiolysis facility based on a laser-driven photocathode electron accelerator has been constructed. First observation of picosecond dynamics in ionic liquid of DEMMA-TFSI in radiation chemistry was reported. It is found that the electrons produced by ionization are solvated to full solvation in ionic liquid with a rate constant of 3.9×1010 s-1, and dry electrons before full solvation react rapidly with biphenyl and pyrene with a rate constant of 3.8-7.9×1011 dm3 mol-1 s-1. The geminate ion recombination in n-dodecane and n-hexane was also observed by monitoring transient optical absorption at 523 nm. © 2008 Elsevier Ltd. All rights reserved

In Vitro Assessment of Factors Affecting the Apparent Diffusion Coefficient of Jurkat Cells Using Bio-phantoms

It is well known that many tumor tissues show lower apparent diffusion coefficient (ADC) values, and that several factors are involved in the reduction of ADC values. The aim of this study was to clarify how much each factor contributes to decreases in ADC values. We investigate the roles of cell density, extracellular space, intracellular factors, apoptosis and necrosis in ADC values using bio-phantoms. The ADC values of bio-phantoms, in which Jurkat cells were encapsulated by gellan gum, were measured by a 1.5-Tesla magnetic resonance imaging device with constant diffusion time of 30sec. Heating at 42℃ was used to induce apoptosis while heating at 48℃ was used to induce necrosis. Cell death after heating was evaluated by flow cytometric analysis and electron microscopy. The ADC values of bio-phantoms including non-heated cells decreased linearly with increases in cell density, and showed a steep decline when the distance between cells became less than 3μm. The analysis of ADC values of cells after destruction of cellular structures by sonication suggested that approximately two-thirds of the ADC values of cells originate from their cellular structures. The ADC values of bio-phantoms including necrotic cells increased while those including apoptotic cells decreased. This study quantitatively clarified the role of the cellular factors and the extracellular space in determining the ADC values produced by tumor cells. The intermediate diffusion time of 30msec might be optimal to distinguish between apoptosis and necrosis