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A selective and reproducible high-performance capillary electrophoretic (HPCE) method for the quantification of amikacin (AMK), an aminocyclitol antibiotic, in human plasma, has been developed for use in clinical laboratory tests. The method involves ultrafiltration (UF) of plasma before derivatization with the fluorescence derivatization reagent 1-methoxy-carbonylindolizine-3, 5-dicarbaldehyde at room temperature for 15 min in the dark. An aliquot of the derivatives is directly introduced into the fused-silica capillary [75 cm (effective length) x 50 microns I.D.] at the anode side by dynamic compression injection (50 hPa for 6 s). After electrophoresis with 40 mM SDS-20 mM phosphate-borate buffer (pH 7) in the micellar electrokinetic chromatography (MEKC) mode at 30 kV, the derivative had a retention time of 16.7 min and was detected by fluorescence intensity at 482 nm (with irradiation at 414 nm). The precision (n = 5) of the method is 4.08 and 1.59% (C.V.) at the 50 and 100 micrograms AMK/ml plasma levels, respectively. Linearity (r = 0.998) was established over the concentration range 5-100 mg of AMK/ml plasma and the detection limit (at a signal-to-noise ratio of 3) is 0.5 microgram AMK/ml plasma. This assay method could potentially have wider application in the determination of other aminocyclitol antibiotics, such as arbekacin, dibekacin, kanamycin, in human plasma as well as of AMK.

A novel lectin was isolated from mycelia of the basidiomycete Pleurotus cornucopiae grown on solid medium. The lectin was purified to homogeneity by mucin-Sepharose affinity chromatography. The molecular mass of the lectin was 40 kDa under reducing conditions, but the subunits were polymerized through disulfide bridges under physiological conditions. Hemagglutinating activity of this lectin was completely inhibited by 2-mercaptoethanol, indicating that the multimer is active. The activity was also inhibited by EDTA, and restored by CaCl2. N-Acetyl-D-galactosamine was the most potent hapten inhibitor. N-terminal amino acid sequence analysis revealed that the mycelial lectin was different from the fruit body lectin of this organism. The mycelial lectin appeared prior to fruit body formation and disappeared during the formation of fruit bodies. The lectin was localized on the surface of solid-medium-grown mycelia, and only dikaryotic, and not monokaryotic, mycelia produced the lectin. These results suggest that the appearance of this lectin is associated with fruit body formation.

Host defence mechanisms associated with the inhibition of translocation of bacteria from the gastrointestinal (GI) tract were investigated in SCID and beige mice after decontamination with oral antibiotics and colonization with Escherichia coli C25. SCID mice, which have impaired T and B cell function, tended to have a greater incidence of bacterial translocation from the GI tract up to 7 days after inoculation compared with controls. However, after 7 days both SCID and controls cleared the E. coli C25 from the liver, spleen, blood and peritoneal cavity. Beige mice, with impaired NK cell and polymorphonuclear leukocyte function, were not able to clear the inoculated bacteria from their liver by 14 days after inoculation although the controls were cleared by 7 days. Numbers of bacteria in the mesenteric lymph nodes (MLN) of beige mice did not decrease significantly by 14 days after inoculation, whereas numbers in SCID mice decreased markedly within 7 days. These results suggest that defence mechanisms other than T and B cell function are important in the inhibition of systemic infection from the GI tract.

Among mushrooms of Pleurotus cornucopiae two kinds of fruit bodies, lectin (PCL)-containing and -deficient, were found. The PCL-deficient fruit body was found to contain a 16.5-kDa protein, which was purified to homogeneity and crystallized. Properties of the protein were investigated in comparison with PCL. The protein consisted of four identical subunits each having a molecular mass of 16.5 kDa, which was close to that of PCL. Partial amino acid sequences of the two proteins were analyzed and some sequence homology was found, although the protein did not cross-react with anti-PCL serum and it was devoid of binding activity for mucin, an inhibitor of PCL. The 16.5-kDa protein was not found in vegetatively growing mycelia, indicating that the synthesis of the protein was developmentally regulated as was PCL. The results suggest that the 16.5-kDa protein was related to PCL.

The complete amino acid sequence of a lectin-related 16.5-kDa protein (PCL-RP) isolated from fruit bodies of a lectin-deficient strain of P. cornucopiae is presented. The sequences of six out of the seven peptides generated by digestion with lysylendopeptidase and four of the five peptides generated by cyanogen bromide cleavage were completely analyzed. Overlapping peptides were obtained by arginylendopeptidase digestion. PCL-RP was a single-chain protein consisting of 144 amino acid residues and its N-terminal serine was blocked with acetate. A proline-rich sequence was found in the carboxyl terminal portion. The N-terminal sequence of PCL-RP showed some homology with those of two known Basidiomycete lectins.

The pharmacokinetics of carboplatin were investigated in cancer patients after single, IV infusion doses of 75, 150, 247.5, 300, 375, and 450 mg/m2. Total plasma and urine platinum and plasma ultrafilterable platinum concentrations were determined by atomic absorption spectrometry. Carboplatin was analyzed in plasma by a specific high-performance liquid chromatography (HPLC) procedure. Total plasma platinum, which represented free carboplatin, protein-bound platinum and metabolites, declined triexponentially; plasma half-lives (t1/2 lambda 1, 0.2 to 0.4 hr; t1/2 lambda 2, 1.3 to 1.7 hr; t1/2 lambda 3, 22 to 40 hr) and total body clearance (CLTB 2.8 +/- 0.5 L/m2/hr) were dose independent. Maximum plasma concentrations (Cmax) and area under the plasma concentration time curve (AUC) increased proportionally with dose. Plasma ultrafilterable platinum and carboplatin concentrations at doses of 375 and 450 mg/m2 declined in a biphasic manner. Plasma carboplatin elimination (t1/2 lambda 1, 0.50 hr; t1/2 lambda 2, 2.2 hr) and CLTB (4.4 to 5.6 L/m2/hr) were also independent of dose; AUC and Cmax increased proportionally to dose. Plasma free platinum was essentially all carboplatin for 8 or 12 hours after administration. Carboplatin did not bind to plasma protein in vitro but did degrade (t1/2-26 hours) to yield a reactive intermediate that bound rapidly and irreversibly to protein. The long terminal elimination half-life of plasma platinum was associated with irreversible binding of a platinum metabonate to plasma protein. The urinary excretion of platinum (0 to 24 hours) accounted for 58 to 72% of doses in 12 to 24 hours. The remainder of the dose is slowly excreted. The pharmacokinetics, in vivo stability, protein binding, and elimination of carboplatin are distinct from the first-generation analog cisplatin.

Nineteen healthy humans (2 men and 17 women) served as experimental subjects in 4 experiments using diets having different levels of leucine and also a valine-deficient diet. The effect of an excess intake of leucine, with and without addition of vitamin B-6, and the effect of a deficiency of valine on urinary excretions of N1-methylnicotinamide, N1-methyl-2-pyridone-5-carboxamide, nicotinic acid, quinolinic acid, and 5-hydroxyindole acetic acid, and on the level of plasma amino acids were investigated. There was no effect of leucine on the excretion of these metabolites, but a marked decrease in the plasma (or serum) valine level was observed. The same decrease was seen when a valine-deficient diet was fed.

In order ot clarify the working conditions and health of dry cleaning workers, we investigated dry cleaning workshops in C ward of Nagoya City. We had the responses from 52 (91%) workshops and 181 (97%) workers. 26 (50%) of the workshops used petroleum solvents, 23 (46%) perchloroethylene, two (4%) 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (R 113), and one (2%) petroleum solvent plus perchloroethylene. Average amounts of solvents consumed per workshop were 1280 kg/year of petroleum solvents, 1450 kg/year of perchloroethylene, and 275 kg/year of R 113. Average number of workers employed in 19 workshops per workshop was 3.6 persons (median 2.0), and the remaining 33(63%) workshops had no employee. The workers complained of strange smell, irritation of eyes, unsteady feeling of head at high rate during week. They also had the high rate of complaints of shoulder stiffness, fatigability, lumbago, and the percentages of them were higher in the workers using petroleum solvents than those in the workers using perchloroethylene. More detailed surveys were made in 13 workshops out of 52. In these cases, average working hours were 11.1 per day and average years of using solvents were 12.9 in workshops using petroleum solvents, 8.4 in those using perchloroethylene including 3.1 years of petroleum solvents. Relatively high concentrations of solvents were detected under the nose of the workers pulling clothes out of dry cleaning machines, near the clothes just pulled out, and about 30 cm above the clothes at brushing with solvents before putting them into the machines. Perchloroethylene leaked from the dry cleaning machine in a workshop. Amount of the total trichlorinated compounds (TTC) in the urine of the workers directly engaged in dry cleaning with perchloroethylene tended to be larger than those of the indirect workers. TTC in both groups, however, were significantly larger than those in the control and in the workers using petroleum solvents. RBC, Hb, an Ht of the female workers in the petroleum solvents workshops were lower than those in perchloroethylene workshops. Liver function tests showed that the average values in the workers directly engaged in dry cleaning with perchloreothylene were significantly larger than those in the indirect workers. A case of malignant lymphoma, a case of liver dysfunction and a case of diabetes mellitus were found among workers directly engaged in dry cleaning. Workers in the small-sized dry cleaning workshops would not be prevented from exposure to organic solvents without the further improvement of administrative guidance and cooperation of the makers of dry cleaning machines and solvents.