Experimental isovalthinuria IV. Incorporation of S35-Methionine or S35-Cystine into urinary isovalthine

In the course of experimental isovalthinuria induced by cholic acid, S35-methionine or S35-cystine administered was incorporated into urinary isovalthine in guinea pigs. Sulfur atom of cysteine seems to be utilized much better for isovalthine synthesis than that of methionine.</p

Effect of cystathionase on isovalthine

In the course of studies on the cleavage reaction of S-(isopropylcarboxymethyl) glutathione (GSIV) into isovalthine in kidney homogenate or glutathionase preparation, it has sometimes been observed that the amount of isovalthine formed is far less than that of GSIV decomposed&#185;. Furthermore, when such reaction mixture is analyzed on an automatic amino acid analyzer, prominent peak corresponding to the reasonable amount of S-(isopropy1carboxymethyl)cysteinylglycine which is an expected intermediate of the GSIV cleavage reaction cannot be found up to 400 effluent ml. Though several reasons may be considered for the explanation of the above curious phenomenon, the effect of cystathionase on isovalthine is at first examined here. But the result was negative. L- and L-Alloisovalthineused as substrate were prepared by the method of OHMORI&#178;. Homoserine and purified cystathionase in ammonium sulfate solution prepared according to the method of GREENBERGB&#179; were kindly furnished by Prof. M. Suda of Osaka University. Incubation mixture contains 0.1 ml of enzyme solution, 1.0 ml of 0.2 M borate buffer (pH 8.0) containing 2×10-&#179;M cysteine, 0.lml of 0.1 M substrate, and 0.8ml of deionized water containing 5×10-4M EDTA. The mixture was shaken at 37°C for 30 minutes in the air. The reaction was terminated by adding 2ml of 10% trichloroacetic acid and the &#945;-keto acids formed were determined by the method of FRIEDEMANN and HAUGEN4 with a following modification: toluene extract was washed once with 8 ml of 10% sodium sulfate. The results obtained are summarized in Table l. When the reaction mixtures are analyzed before or after incubation on an automatic amino acid analyzer, the amount of L- or L-Alloisovalthine is found to be unchanged. Furthermore, as indicated in Table 1, L-isovalthine showed no inhibitory effect on the homoserine cleavage by cystathionase. Since amino acid oxidases have already been reported to have no effect on isovalthine&#179;, the curious phenomenon above cited may have to be explained by other reaction mechanism such as transpeptipation reaction.</p

A digital twin prototype to visualize heterogeneous seismic damage simulation results on web-GIS

Access to a wide range of information tailored to specific purposes, including extensive damage projections and statistics for target areas and the potential for individual building and dwelling damage predicted through simulations, enhances cities’ resilience against large-scale earthquakes. Recognizing the significance of this, we have developed a prototype of a digital twin capable of comprehensively visualizing various simulations on a web-based geographic information system (GIS) platform. This prototype employs three seismic damage simulators: the Integrated Earthquake Simulation for area damage, the wallstat for wooden houses, and the E-Simulator for a reinforced concrete building. A trial of earthquake damage simulations was conducted to assess this prototype’s efficacy, focusing on the damage incurred in Mashiki Town during the 2016 Kumamoto earthquake. The trial successfully verified the capability of the system to visualize and integrate various types of simulation data alongside records obtained from actual earthquake disasters. This paper provides an overview of the digital twin prototype. It reports on the trial’s results, focusing on the visualization and integration achieved through this trial