Acceleration of Methaemoglobin Reduction by Riboflavin in Human Erythrocytes

The effect of riboflavin on nitrite treated erythrocytes from normal subjects and patients with hereditary methaemoglobinaemia due to the deficiency of NADH-cytochrome b₅ reductase was studied in the presence of glucose, 2-deoxy-d-glucose or lactate. When glucose or 2-deoxy-d-glucose was used as a substrate for these erythrocytes, the rate of methaemoglobin reduction in these cells was accelerated more than two-fold in the presence of riboflavin. The acceleration was dependent on the concentration of riboflavin and was suppressed by the addition of atebrin. The stimulative effect of riboflavin was, however, not observed when lactate was used in place of glucose or 2-deoxy-d-glucose. On the basis of these results, the acceleration of methaemoglobin reduction by riboflavin was considered to be due to the activation of NADPH-flavin reductase (Yubisui et al , 1977) in erythrocytes by the reagent. The availability of riboflavin for patients with methaemoglobinaemia due to the deficiency of NADH-cytochrome b₅ reductase and for those with toxic methaemoglobinaemia is discussed in relation to methaemoglobin reducing systems in erythrocytes.     

Serum HDL-cholesterol-increasing and fatty liver-improving actions of Panax ginseng in high cholesterol diet-fed rats with clinical effect on hyperlipidemia in man

Effects of Panax ginseng on plasma and hepatic lipids were investigated in the high cholesterol diet-fed rats and in patients with hyperlipidemia. Oral administration of red ginseng powder reduced plasma total cholesterol, triglyceride and NEFA, while plasma HDL-cholesterol was elevated. Platelet adhesiveness was also reduced by ginseng administration. The plasma lipid-improving actions were also observed in patients with hyperlipidemia. Hepatic cholesterol and triglyceride contents were decreased and phospholipid increased by ginseng administration in the high cholesterol diet-fed rats, corresponding to improvement of the fatty liver.     

Studies on phage type, beta-lactamase activity and sensitivity of multiple drug-resistant Staphylococcus aureus isolated from clinical specimens to cefmetazole

The 868 strains of S. aureus were isolated at the Department of Pediatrics, Third Hospital and Aoto Hospital, The Jikei University, School of Medicine and the Kanagawa Prefectural Nursing and Hygienic School Hospital during 6 months from May to October in 1981. From them 66 strains not sensitive to CEZ were selected by a 3-concentration disk method. A total number of 54 strains except for 12 isolated from the same infant patient was examined for their MIC's for 6 drugs, CMZ, CEZ, CTM, CXM, MCIPC and GM. Moreover, phage typing and beta-lactamase activity determination were carried out in them. 1. Antibacterial activity Sixty-six (7.6) of 868 strains were not sensitive to CEZ. The MIC's of CMZ against these resistant strains were between 1.56 and 50 micrograms/ml with a peak between 3.13 and 6.25 micrograms/ml when the 10(5) cells/ml bacterial suspension were inoculated. CMZ was superior in antibacterial activity to CEZ and CXM by about 4 degrees and to CTM by about 3 degrees. MCIPC and GM has higher antibacterial activity against a few strains than CMZ. However, the number of strains with MIC higher than or equal to 50 micrograms/ml was 17 for MCIPC and 40 for GM, but only 2 for CMZ. Thus, the former 2 drugs were far inferior to the latter one. 2. Phage type (1) Nineteen strains (35.2%) had MIC's for CEZ greater than 50 micrograms/ml and CMZ less than 6.25 micrograms/ml. Seventeen of them belonged to the nontypable. (2) Fourteen (25.9%) had MIC's for CEZ greater than 100 micrograms/ml. Of them 9 were allocated to the group III, 3 to the mixed (I + II + III, I + III) group and 2 to the nontypable. (3) Of 20 strains (37.0%) which had MIC's for CEZ greater than 100 micrograms/ml and CMZ less than 6.25 micrograms/ml 5 belonged to the group I, 3 to the group III and 12 to the nontypable. (4) Five strains classified into the group I were all isolated at the Kanagawa Perfectural Nursing and Hygienic School Hospital. (5) Eleven of 15 strains belonging to the group III were isolated at the Third Hospital, The Jikei University, School of Medicine. (6) Seventeen of 21 strains isolated at the Aoto Hospital, The Jikei University, School of Medicine belonged to the nontypable. (7) Phage type was considered to be influenced by difference in areas, infection within hospitals, etc., 3. beta-Lactamase activity beta-Lactamase activity was demonstrated at levels between 0.07 and 3.26 mumol/min/mg in all 54 strains. There was no correlation between MIC for CEZ or CEZ and beta-lactamase activity. It was suggested that beta-lactamase might not contribute to mechanism of resistance of S. aureus to each drug examined.     

Studies on metal chelating polymers, 3. Metal chelates of cationic polymers containing the 3-formyl- or the 3-acetyl-4-hydroxybenzyl group in the side chain

The stability constants for several metal complexes (Cu(II), Ni(II), Zn(II), Co(II), Fe(III), Al(III)) of terpolymers from diallyl[3-formyl (or 3-acetyl-) 4-hydroxybenzyl]methylammonium chloride, diallyldimethylammonium chloride, and sulfur dioxide were determined by potentiometric titration. The results are discussed comparing the stability constants with those of o-hydroxybenzaldehyde and o-hydroxyacetophenone derivatives.     

Negative association between serum dioxin level and oxidative DNA damage markers in municipal waste incinerator workers

Objectives: To investigate the effect of dioxin on the formation of oxidative DNA damage and urinary mutagenicity, we measured the concentrations of serum dioxins and lymphocytic 8-hydroxydeoxyguanosine (8-OH-dG) in 57 male waste incinerator workers, urinary 8-OH-dG and urinary mutagenicity in 29 male waste incinerator workers. Methods: Information about the subjects was obtained from a questionnaire. Concentrations of polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), and coplanar-polychlorinated-biphenyl (Co-PCB) in serum samples from the workers were measured with a high-resolution gas chromatograph /high-resolution mass spectrometer. Lymphocytic and urinary 8-OH-dG levels were measured with a high-performance liquid chromatography-electrochemical detector system. The urinary mutagenicity was measured with umu assay. Results: The lymphocytic 8-OH-dG level showed a negative association with the serum dioxin level (total value of TEQ-PCDD, PCDF, and Co-PCB). Urinary 8-OH-dG did not show correlation with serum dioxin level, but showed positive correlation with the smoking index. Conclusions: With respect to the subjects‘ serum dioxin level, dioxin did not increase the urinary 8-OH-dG level by oxidative DNA damage, but upregulation of the primary defenses with oxidative damage and/or DNA repair system activity might have occurred.