Effects of aminoguanidine and pyridoxal phosphate on glycation reaction of aspartate aminotransferase and serum albumin.

Effects of aminoguanidine (AG) on binding of glucose and pyridoxal phosphate (PLP) to albumin, and on glycation reaction of cytosolic aspartate aminotransferase (cAST) were examined in an in vitro system. AG was found to inhibit not only glycation of albumin but binding of PLP to albumin, indicating that distribution of PLP into tissues is inhibited by AG. AG bound to PLP directly to produce a new compound, and in this manner AG inhibited cAST activity. AG could also inhibit glycation of cAST and the extent of inhibition was varied with sugars used. It appears that, although AG is a useful inhibitor of glycation proteins, it may be toxic from the viewpoints of vitamin B6 as an essential nutrient and also PLP-dependent enzymes.

[A case of fixed drug eruption due to ephedrine hydrochloride].

We report the case of a 29-year old female who developed a fixed drug eruption due to ephedrine hydrochloride administered intravenously during the cesarean section. On the day of the operation a palm-sized dark brown macula with half egg-sized erosion appeared on her right lower thigh. We diagnosed her disease as fixed drug eruption and examined the causative agent among all the 14 drugs used from admission to the appearance of fixed drug eruption. Each of systemic challenge, patch test on the lesion, intradermal and subcutaneous injection on the lesion with ephedrine hydrochloride showed positive reaction. As far as we have been able to search, our case is the first one of fixed drug eruption due to ephedrine hydrochloride.

Leiomyoma of the prostate: CT and MR findings.

Pure prostatic leiomyoma is very rare. We report a case of magnetic resonance imaging findings of prostatic leiomyoma. The mass was expansile and had a slightly higher signal intensity than skeletal muscle on T2-weighted images. Normal prostatic glandular tissue could be clearly distinguished from the tumor.

Successful transvaginal repair of a rectovaginal fistula developing after double-stapled anastomosis in low anterior resection: report of four cases.

The management of postoperative rectovaginal fistula (RVF) after low anterior resection for rectal cancer is difficult and the results are often unsatisfactory. Among 140 patients with rectal cancer who underwent low anterior resection with a double-stapled anastomosis at our hospital between 1986 and 1996, 4 (2.9%) developed RVF as a postoperative complication. The RVF developed gradually from 9 to 128 days after low anterior resection. We describe herein our technique of using a modified transvaginal approach for RVF repair with a diverting colostomy. In all four patients, the RVFs were completely eradicated with reestablishment of intestinal continuity and did not recur during the mean follow-up period of 29.5 months, ranging from 12 to 67 months. This report serves to demonstrate that emerging RVFs secondary to stapled anastomosis in low anterior resection for rectal cancer must be recognized, and that a modified transvaginal approach provides an effective method of repair.

Saccharide production from methanol by transposon 5 mutants derived from the extracellular polysaccharide-producing bacterium Methylobacillus sp. strain 12S.

A CH3OH-utilizing bacterium that has the ability to produce extracellular polysaccharide (EPS) was isolated from a soil sample, and was identified as the obligate methylotroph Methylobacillus sp. strain 12S on the basis of its 16S rDNA sequence and growth-substrate specificity. The EPS produced by strain 12S was purified and the sugar composition was analysed by GC-MS and HPLC to reveal that the EPS was a heteropolymer composed of glucosyl, galactosyl, and mannosyl residues in the molar ratio 3:1:1. In order to produce mono- and/or oligosaccharides by single-step fermentation from CH3OH, stain 12S was mutagenized by transposon 5. Among eleven EPS-deficient mutants, three strains were found to accumulate significant amounts of reducing sugars in the media. The amounts of the reducing sugars produced by the mutants ( > ca. 700 mg glucose equivalent/l) were > 11-22 times higher than those produced by the wild-type strain (

Analysis of kinetic rate constants in [18F]fluorodeoxyglucose model using a least square fitting package SALS (statistical analysis with least squares).

The analysis of kinetic rate constants in the compartment model for [18F]fluorodeoxyglucose (FDG) was undertaken. Four kinetic rate constants were determined with a least square fitting package SALS (Statistical Analysis with Least Squares), using the measured data of 18F activity as a function of time. SALS calculations were found to be easy and quick with high precision. The rate constants and the curves fitted by the k3 and the k4 models were compared in situations with various degree of cerebral glucose metabolism during positron emission tomography (PET) studies. The k4 model in the determination of cerebral metabolic rate for glucose (CMRglu) was much superior than the k3 model in any given situation as it always underestimates the metabolic rate. However, the k3 model produces less variation when the cerebral radioactivity curve shows steady rising pattern.