Eiichi Osono

Efficacy of gentian violet in the eradication of methicillin-resistant Staphylococcus aureus from skin lesions

The efficacy of gentian violet (Gv) in eradicating methicillin-resistant Staphylococcus aureus (MRSA) in decubitus ulcers was investigated. Decubitus ulcers (a total of 18 cases) were scrubbed with Gv aqueous solution 0.1% and ointment containing Gv 0.1% was applied daily. MRSA was not detected in these lesions for 3-34 days (average, 10.5 +/- 2.5 days) after the application of Gv ointment. Before this trial, all patients were treated with povidone-iodine and antibiotics; however, those treatments were not effective in eradicating MRSA from skin lesions. Skin irritation and other systemic side effects caused by Gv were not observed. Our data suggest that Gv is a useful agent for treatment of the decubitus ulcers infected with MRSA.

Rapid Induction of Apoptosis in CD8+ HIV-1 Envelope-Specific Murine CTLs by Short Exposure to Antigenic Peptide

During primary viral infection, in vivo exposure to high doses of virus causes a loss of Ag-specific CD8+ T cells. This phenomenon, termed clonal exhaustion, and other mechanisms by which CTLs are deleted are poorly understood. Here we show evidence for a novel form of cell death in which recently stimulated CD8+ HIV-1 envelope gp160-specific murine CTLs become apoptotic in vitro after brief exposure to free antigenic peptide (P18-I10). Peak apoptosis occurred within 3 h of treatment with peptide, and the level of apoptosis was dependent on both the time after initial stimulation with target cells and the number of targets. Using T cell-specific H-2Dd/P18-I10 tetramers, we observed that the apoptosis was induced by such complexes. Induction of apoptosis was blocked by cyclosporin A, a caspase 3 inhibitor, and a mitogen-activated protein kinase inhibitor, but not by Abs to either Fas ligand or to TNF-α. Thus, these observations suggest the existence of a Fas- or TNF-α-independent pathway initiated by TCR signaling that is involved in the rapid induction of CTL apoptosis. Such a pathway may prove important in the mechanism by which virus-specific CTLs are deleted in the presence of high viral burdens.

Synergistic bactericidal effects of acrinol and tetracycline against Pseudomonas aeruginosa

Abstract Combined treatment of acrinol (Ac) and tetracycline hydrochloride (Tc) against Pseudomonas aeruginosa strains isolated from clinical specimens synergistically increased the bactericidal effect. The minimum bactericidal concentration (MBC) of Ac against P. aeruginosa strain no. 985 was 200 μg/ml, while the MBC of Ac against strains no. 47 and no. 783 was above 800 μg/ml for each. The MBC of Tc was above 400 μg/ml against each of the tested strains. However, simultaneous treatment with 25 μg/ml Ac and 200 μg/ml Tc against P. aeruginosa strain no. 985 decreased the viable cell number from 107 cfu/ml to <10 cfu/ml within 24 h, while a higher concentration of Tc (400 μg/ml) with Ac (25 μg/ml) reduced the viable cell number to <10 cfu/ml within 8 h. A similar synergistic bactericidal effct of Ac and Tc was observed in strains no. 47 and no. 783 by treatment with 200 μg/ml Ac and 200 μg/ml or 400 μg/ml Tc. The degree of bactericidal effect against P. aeruginosa was proportional to the concentration of Tc under the condition of a constant concentration of Ac. Furthermore, Ac-treated cells of strain no. 47 were killed by a following Tc treatment, but cells pretreated with Tc did not show such a sensitivity to Ac. To induce the synergistic effect of Ac and Tc, Ac must be applied to P. aeruginosa before or at the same time as Tc.

Serum leptin concentration in kidney transplantation patients

BackgroundAlthough recipients of kidney transplantation tend to be obese, the factors that cause obesity, including steroid and cyclosporin administration after kidney transplantation, are not fully understood. Because leptin, the gene product of theob gene, has been shown to play an important role in controlling the appetite in rodents, it might have a similar role in humans.MethodsWe examined the serum leptin concentration in 16 patients who had undergone kidney transplantation. The transplantation group was matched with a control group by age, body mass index, and serum creatinine level.ResultsThe serum leptin concentration of the kidney transplantation group was significantly higher than that of the control group. The results also indicated that serum leptin concentration was related to body mass index, serum insulin, and triglyceride concentration in the kidney transplantation group. A significant correlation was also found between the serum insulin level and the triglyceride concentration in the transplantation group. The serum leptin concentration was not related to dosage of maintenance prednisolone, total prednisolone, maintenance cyclosporin, total cyclosporin, nor to the cyclosporin trough level.ConclusionsThe serum leptin concentration was related to the body mass index and concentrations of serum insulin and triglyceride, but was not related to the doses of administored prednisolone and cyclosporin.

Pharmacokinetics of nafamstat mesilate (FUT) in patients undergoing hemodialysis.

血液透析患考と健常考の間に, メシル酸ナファモスタット (FUT) の体内動態, 作用動態上差が認められるか否かを検討するためにFUTの全身投与を行い, 血中濃度およびセライト活性化凝固時間 (ACT) を経時的に測定した.FUTの凝集抑制に関する有効血中濃度は1,580ng/ml以上, 作用発現は投与直後で, 作用消失時間が投与終了後2分と速効性, 短時間作用性を示した.薬物分布容積 (Vd: HD群0.08±0.07/Nr群0.36±0.23l/kg) 総体クリアランス (CL: 0.02±0.01/0.07±0.04mlmin/kg) はHD群で小さく内シャント等の影響が考えられたが, 血中濃度半減期 (t1/2: 1.04±0.60/1.73±1.49min) 薬物排泄恒数 (Kel: 0.83±0.36/Nr群0.64±0.40min-1) は健常者群より良く, 理論上腎不全による代謝遅延等の問題はないものと思われた.