Functional characterization and evolutionary implication of the internal 157-amino-acid sequence of an exoinulinase from Penicillium sp. strain TN-88

An extracellular exoinulinase from the filamentous fungus Penicillium sp. strain TN-88 has a 14-fold higher specific activity of 743 U/mg toward inulin than its equivalent from the Aspergillus niger strain 12 and possesses an internal 157-amino-acid sequence whose corresponding region is absent in the A. niger enzyme. On the basis of sequence alignment, the internal region D' encoding the 157-amino-acid sequence in the Penicillium exoinulinase gene inuD cDNA was inserted into the site between the nucleotides 897 and 898 of the A. niger exoinulinase gene inuE cDNA. The resultant inuE::D' fusion was expressed in the methylotrophic yeast Pichia pastoris. The K(m) value of the secreted hybrid enzyme InuE::D' for inulin hydrolysis was about 1/15 that of the A. niger InuE, whereas its k(cat) value did not differ greatly from that of the InuE. These observations indicate that the Penicillium exoinulinase has evolved by the horizontal transfer and integration of a relevant DNA segment and that the internal sequence D' functions as an additional noncatalytic inulin-affinity region.     

Ion-exchangeable layered niobates as photocatalysts

Silica pillared-niobates were prepared from a, so called, layered perovskite, KCa₂Nb₃O₁₀, by using alkylammonium ions as swelling reagents.A product with the interlayer spacing expanded by ca. 1.2 nm and the BET surface area of ca. 200 m²/g was obtained when an octylammonium intercalated precursor was used. The photocatalytic activities of these silica pillared-niobates were compared with those of the original KCa₂Nb₃O₁₀ and the proton-exchanged derivative. It was revealed that silica pillared-niobates showed a high and characteristic photocatalytic activity.     

Application of synthetic fluid inclusions to simultaneous temperature–pressure logging in high-temperature (sub- to supercritical) geothermal systems

Batch-autoclave experiments have been conducted to evaluate the potential use of synthetic fluid inclusions as a simultaneous temperature–pressure (and fluid sampling) logging tool in deep-seated, high-temperature (>350 °C) geothermal systems. The application of synthetic fluid inclusions allows us to obtain information about thermal-pressure conditions in deep-seated geothermal systems, where conventional tools cannot be used because of the extreme temperature conditions. Fluid inclusions, up to 50 μm long, have been readily synthesized during 5-day autoclave experiments (conducted at 375–475 °C and 39–62 MPa) in pre-fractured, inclusion- and impurity-free artificial quartz. Inferred fluid inclusion (temperature–pressure) trapping conditions are calculated by deducing the intersection of isochores derived from microthermometric data for three sets of simultaneously trapped synthetic fluid inclusions in healed microfractures. Synthetic fluid inclusion logging offers a precise borehole temperature measurement technique without need of any pressure correction. Pressure estimates are less precise, although the method may be improved by using a combination of H₂O–NaCl and H₂O–KCl solutions/salinities, and fluid/quartz/amorphous silica systems that facilitate crack healing but trap fluids that do not homogenize at near-critical conditions.     

Analysis for microbial contamination in production of Japanese-style confectionery "Monaka"

Food hygiene in Japanese-style confectionery factories is hard to practice because the businesses are small. In a supporting system of voluntary-based hygienic management in this field, we microbiologically investigated the production processes of "Monaka" in a workshop in Tokyo. We microbiologically assessed the processing environments as well as the products in the workshop, then proposed some improvements in the production of the confectionery. After the improvements, microbial contamination of the processing environments was reduced and no microbial contamination was found in the sugared bean, or "An" produced, though the product "Monaka" was still contaminated, especially by molds. It was clarified that the molds came from contaminated baked wheat shells, or "Kawa" and further that the wheat shells were contaminated by molds during storage.     

Numerical study on particle motions in swirling flows in a cyclone separator

The purpose of this study is to establish the high-accurate prediction method of particle separation in a cyclone separator. Numerical simulation of the swirling flows in a cyclone separator is performed by using a large eddy simulation (LES) based on a Smagorinsky model. The validity of the simulation and the complicated flow characteristics are discussed by comparison with experimental results. Moreover, particle motions are treated by a Lagrangian method and are calculated with a one-way method. A performance for particle separation is predicted from the results of the particle tracing. As results of our investigation, the influences of the inserted height of the outlet pipe on the performance for particle separation of cyclone separator are shown.     

Microsatellite instability and frameshift mutations in the Bax gene in hereditary nonpolyposis colorectal carcinoma

Patients with ulcerative colitis (UC) are at higher risk for cancer. Risk factors are duration of disease, extent of colitis, associated primary sclerosing cholangitis and possibly early onset of UC in childhood. Epithelial dysplasias are considered as precursors of colorectal cancer within the concept of an inflammation-dysplasia-carcinoma sequence. Dysplasia originates multifocally and is difficult to identify by colonoscopy. Histomorphological diagnosis can also be problematical. Surveillance programs utilize colonoscopy with random biopsies to diagnose dysplasia in patients with risk factors. The efficiency of these programs can be markedly increased when certain rules are applied. The ultimate aim must be to perform a proctocolectomy in patients at higher risk before invasive cancer develops. With only a few exceptions, colorectal cancer in UC can be treated by restorative proctocolectomy. Partial resection of the colon should be avoided because of the high frequency of occult carcinomas and multifocal carcinogenesis. There are first results that indicate a higher risk for malignant deterioration in the terminal ileum. After an ileoanal pouch procedure patients with chronic pouchitis seem to have a higher risk for dysplasia. At the moment the risk for malignancy cannot be calculated because of the relatively short follow-up time after ileoanal pouch procedures. However, it is recommended that after restorative proctocolectomy patients be followed by endoscopy and random biopsies for the rest of their lives.