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

Spontaneous Regression of Myxofibrosarcoma of the Thigh after Open Biopsy

Spontaneous regression of sarcoma is exceedingly rare. A 62-year-old male presented with myxofibrosarcoma of the thigh which regressed after open biopsy. Treatment strategy for this condition is not well-documented in the literature. In this report, we describe the case of a spontaneously regressed myxofibrosarcoma successfully treated by resection where the extent of the tumor was determined from the initial MRI. This case demonstrates that myxofibrosarcoma has the potential to regress spontaneously, and astute awareness of this phenomenon is necessary for appropriate management of this condition

Guideline for Hereditary Angioedema (HAE) 2010 by the Japanese Association for Complement Research - Secondary Publication

ABSTRACTThis guideline was provided by the Japanese Association for Complement Research targeting clinicians for making an accurate diagnosis of hereditary angioedema (HAE), and for prompt treatment of the HAE patient in Japan. This is a 2010 year version and will be updated according to any pertinent medical advancements

Pathway-dependent quantitative self-assembly of a metastable Pd6L4 square-based pyramid promoted by template and assist anions

Precise control of molecular self-assembly process is one of ultimate goals in molecular self-assembly because this enables us to make a rational design of self-assembly pathway to selectively obtain even metastable assemblies, which is impossible under thermodynamic control. Toward this goal, modulation of the energy landscape of molecular self-assembly is demanded. Here, we report that a metastable Pd6L4 square-based pyramid (SP) was almost quantitatively assembled by a pathway-dependent process with the aid of template and assist anions, which properly modulate the energy landscape, while usual heating a mixture of building blocks without modulation of the energy landscape gave a mixture of Pd6L4 SP and uncharacterized species in equilibrium. These results indicate that synergy of template and assist effects is powerful approach for pathway selection in metal-organic assembly resulting in a metastable product selectively

Vertical distribution of amino acids and chiral ratios in deep sea hydrothermal sub-vents of the Suiyo Seamount, Izu-Bonin Arc, Pacific Ocean

A high temperature deep sea hydrothermal system related to dacitic arc volcanism has been drilled using a tethered, submarine rock drill system as a part of the Archaean Park Project. The benthic multi-coring system (BMS) employed allows for direct sampling of microorganisms, rocks and fluids beneath hydrothermal vents. The samples examined in this study are from sites APSK 08, 09 and 10 on the Suiyo seamount of the Izu-Bonin Arc in the Pacific Ocean. Based on the vertical distribution and stereochemistry of amino acids in this vigorous sub-vent environment, a model of deep sea subterranean chemistry and biology is proposed, describing optimal microbial activity rather than abiotically synthesized amino acids components. Total hydrolyzed amino acids in the hydrothermal sub-vent core samples are of the order of 101–102 nmol/g-rock. The ratios of β-alanine/aspartic acid and γ-aminobutyric acid/glutamic acid are low, consistent with a large microbial population and fresh subterranean bioorganic compounds. The d/l ratios of chiral amino acids such as aspartic acid, glutamic acid and alanine in these rock samples were overall also quite low. Large enantiomeric excesses of l amino acids also support the existence of a vigorous subjacent microbial oasis in this seamount hydrothermal sub-system. The present findings represent crucial evidence that sub-vent regions are a previously unknown extreme environment biosphere, extending the known subterranean habitable spaces