Further investigation of phenanthroindolizidine alkaloids from Tylophora tanakae

In addition to ten alkaloids previously described, we have isolated two alkaloid N-oxides from Tylophora tanakae MAXIM. (Asclepiadaceae). Further, the polar fraction of the leaves and caules of this plant cultivated in a farm afforded two new polar alkaloids. The structures of the four products were determined. The relation between the structure and cytotoxic activity of this group of alkaloids is discussed.     

Application and Simplification of Cell-Based Equivalent Circuit Model Analysis of Electrical Impedance for Assessment of Drop Shock Bruising in Japanese Pear Tissues

This study was conducted with the objective of applying cell-based electrical equivalent circuit analysis for the assessment of bruising of tissues in Japanese pears after drop tests, as well as to simplify the analysis. The equivalent circuit analysis of electrical impedance values was conducted on the bruised regions of the pear tissues. The analysis showed that the resistance of the protoplasm of the injured tissues slightly increases, and the capacitance of cell membranes and the resistance of apoplastic fluids significantly decrease. Thus, it was theorized that these parameters are influenced by cell membrane destruction. Further, it was found that Cole-Cole plot parameter obtained from the frequency characteristics of the impedance of the tissues can express changes in the apoplastic fluid resistance. These results show that equivalent circuit analysis can be used to assess bruising of pear cells caused by drop shock, and the analysis can be simplified using Cole-Cole plots. We expect these results to aid in the development of physical damage assessment methods for distributed fruits.     

Alpha-Amylase from Persimmon Honey: Purification and Characterization

The α-amylase was extracted from pure persimmon honey and purified by DEAE-Toyopearl 650M, CM-Toyopearl 650M, and Toyopearl HW-55F column chromatographies. Molecular weight of purified enzyme was estimated to be about 58 kDa by Toyopearl HW-55F gel chromatography and SDS-PAGE, respectively suggested that the purified enzyme was a monomer. Optimum pH of the enzyme was 6.0?7.0 and optimum temperature 40°C. The enzyme was extremely inactivated at pH was higher than 7.0 or lower than 5.0. Heat inactivation occurred at 40°C. This enzyme activated by Ca ²⁺ , Mn²⁺, PCMB, and DTNB, but inhibited by Ba²⁺, Fe³⁺, Hg²⁺, Mg²⁺, and iodoacetic acid. The purified enzyme was of α?-type by TLC analysis. The relative rate of hydrolysis of the polymeric substance decreased with decreasing percentage of α?-1,4-linkages and with increasing percentage of α?-1,6-linkages in substrate similar to the results from commercially available honey.     

Antioxidative Activities and Angiotensin I-Converting Enzyme Inhibition of Extracts Prepared from Chum Salmon (Oncorhynchus Keta) Cartilage and Skin

The extracts from cartilage and skin of chum salmon were prepared using a pressure cooker. As a result, protein and collagen contents in extracts from cartilage and skin was higher than those only in cartilage. The inhibition activity of linoleic acid oxidation was high in extract from cartilage. The scavenging activity of cartilage extract was higher than those of cartilage and skin against all reactive oxygen species, such as superoxide anion, hydroxyl, and DPPH radicals. On the other hand, angiotensin I-converting enzyme inhibitory activity of cartilage extract was about seven times as high as that of cartilage and skin extract. The present studies indicate that the extracts, particularly from cartilage, have angiotensin I-converting enzyme inhibitory activity that functions to depress hypertension, and antioxidant activity, which acts to prevent of life-style related diseases such as cancer, cardiovascular diseases, and diabetes. The data should be useful for developing a novel type of functional seasoning.     

KBO Orientability

This article presents three new approaches to prove termination of rewrite systems with the Knuth–Bendix order efficiently. The constraints for the weight function and for the precedence are encoded in (pseudo-)propositional logic or linear arithmetic and the resulting formula is tested for satisfiability using dedicated solvers. Any satisfying assignment represents a weight function and a precedence such that the induced Knuth–Bendix order orients the rules of the encoded rewrite system from left to right. This means that in contrast to the dedicated methods our approach does not directly solve the problem but transforms it to equivalent formulations for which sophisticated back-ends exist. In order to make all approaches complete we present a method to compute upper bounds on the weights. Furthermore, our encodings take dependency pairs into account to increase the applicability of the order. The first and third authors are supported by FWF (Austrian Science Fund) project P18763 and the second author is supported by the Grant-in-Aid for Young Scientists 20800022 of the Ministry of Education, Culture, Sports, Science and Technology of Japan.     

Influence of Pt–Ba Proximity on NO x Storage–Reduction Mechanisms: A Space- and Time-Resolved In Situ Infrared Spectroscopic Study

The influence of Pt–Ba proximity on the performance and mechanism of NO _x storage–reduction (NSR) was investigated by a comparative study of Pt–Ba/CeO₂, Pt/CeO₂ and mechanically mixed Pt/CeO₂–Ba/CeO₂. NO _x storage capacity, regeneration activity and selectivity to nitrogen and ammonia during periodic lean (NO + O₂)–rich (H₂) cycles were evaluated and the chemical gradients along the axial direction of the catalyst beds were monitored by space- and time-resolved in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The presence of Ba and its proximity to Pt greatly influenced the NSR process. In particular, the proximity was crucial to achieve better utilization of bulk Ba components as well as enhancing selectivity to N₂. The space-resolved approach is shown to be a powerful tool to understand the impact of the proximity of Pt and Ba constituents on the final NSR performance.     

Chymase as a Novel Therapeutic Target in Acute Pancreatitis

Acute pancreatitis is still a life-threatening disease without an evidenced therapeutic agent. In this study, the effect of chymase in acute pancreatitis and the possible effect of a chymase inhibitor in acute pancreatitis were investigated. Hamsters were subcutaneously administered 3.0 g/kg of L-arginine to induce acute pancreatitis. Biological markers were measured 1, 2, and 8 h after L-arginine administration. To investigate the effect of a chymase inhibitor, a placebo (saline) or a chymase inhibitor TY-51469 (30 mg/kg) was given 1 h after L-arginine administration. The survival rates were evaluated for 24 h after L-arginine administration. Significant increases in serum lipase levels and pancreatic neutrophil numbers were observed at 1 and 2 h after L-arginine administration, respectively. Significant increases in pancreatic neutrophil numbers were observed in the placebo-treated group, but they were significantly reduced in the TY-51469-treated group. A significant increase in the pancreatic tumor necrosis factor-α mRNA level was observed in the placebo-treated group, but it disappeared in the TY-51469-treated group. Chymase activity significantly increased in the placebo-treated group, but it was significantly reduced by treatment with TY-51469. The survival rate significantly improved in the TY-51469-treated group. A chymase inhibitor may become a novel therapeutic agent for acute pancreatitis.