An LC method for quantifying bepridil in human plasma using 1-naphthol as the internal standard.

A modified method for the quantitative determination of bepridil hydrochloride in human plasma is described. This method is unrelated to chemical methods currently in use. The mobile phase is 50 mM phosphate buffer (pH3.0)-methanol-acetonitrile-triethylamine (57:3:40:1, v/v), and the samples are fractionated on a C8-3 column (150 × 4.6 mm, 5 µm) using a flow rate of 0.9 mL/min. Bepridil was detected by UV spectroscopy at 254 nm. The retention times of bepridil and 1-naphthol were 12.6 min and 7.5 min, respectively; there was no interference originating from human plasma. We confirmed that the bepridil and 1-naphthol peaks were not influenced by the presence of 32 commercial medicines frequently co-administered with bepridil. Additionally, the concentration of bepridil in the plasma of five patients treated with bepridil for atrial fibrillation was measured. These samples were collected just before each dosage of bepridil. Their rhythm and rate control were well maintained. Trough concentrations ranged from 233.9 to 347.4 ng/mL, similar to previously reported values.

Novel cyclohexene derivatives as anti-sepsis agents: synthetic studies and inhibition of NO and cytokine production.

In order to develop an anti-sepsis agent, a series of cyclohexene derivatives were synthesized and evaluated for their biological activities. Through modification of the sulfonamide spacer moiety depicted by formula II, it was found that the benzylsulfone derivative 10a had potent inhibitory activity against the production of NO. Further modifications of the phenyl ring, ester moiety, and benzyl position of benzylsulfone derivatives III were carried out. Among these compounds, (R)-(+)-10a and (6R, 1S)-(+)-22a showed strong inhibitory activity not only against NO production but also against inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in vitro. Furthermore, (R)-(+)-10a and (6R, 1S)-(+)-22a protected mice from LPS-induced lethality in a dose-dependent manner.

Outbreak of Salmonella oranienburg infection in Japan.

We experienced five cases of Salmonella oranienburg infection in children living in Saitama prefecture. Thereafter the number of patients with S. oranienburg infection increased not only in Saitama (55 cases) but also in other parts of Japan in 1999 (1505 cases) in 1999. The source of S. oranienburg infection was identified as a snack made from semi-dry cuttlefish.

Discovery of novel and potent small-molecule inhibitors of NO and cytokine production as antisepsis agents: synthesis and biological activity of alkyl 6-(N-substituted sulfamoyl)cyclohex-1-ene-1-carboxylate.

To develop a new therapeutic agent for sepsis, screening of the Takeda chemical library was carried out using mouse macrophages stimulated with lipopolysaccharide (LPS) to identify a new class of small-molecule inhibitors of inflammatory mediator production. The lead compound 5a was discovered, from which a series of novel cyclohexene derivatives I bearing a sulfamoyl and ester group were designed, synthesized and tested for their inhibitory activity against nitric oxide (NO) production. Derivatives I were synthesized by the coupling of sulfonyl chlorides and anilines with concomitant double bond migration in the presence of triethylamine, and phenyl ring substitution and modification of the ester and cyclohexene moieties were carried out. Among the compounds synthesized, ethyl (6R)-6-[N-(2-chloro-4-fluorophenyl)sulfamoyl]cyclohex-1-ene-1-carboxylate [(R)-(+)-5n, TAK-242] was found to exhibit the most potent suppressive activity for the production of not only NO but also inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) induced by LPS-stimulated mouse macrophages with IC50 values of 1.8, 1.9 and 1.3 nM, respectively. It shows marked beneficial effects in vivo also. Intravenous administration of (R)-(+)-5n at doses of 0.1 mg/kg or more suppressed the production of NO and various cytokines [TNF-alpha, IL-6 and IL-1beta] in the mouse endotoxin shock model. Furthermore, it protected mice from death dose-dependently and all mice survived at a dose of 3 mg/kg. The minimum effective dose to protect mice from lethality in this model was 0.3 mg/kg, which was consistent with those for inhibitory effects on the production of NO and cytokines. Compound (R)-(+)-5n is currently undergoing clinical trials for the treatment of sepsis.

Pharmacokinetics and efficacy of low-dose methotrexate in patients with rheumatoid arthritis.

This article evaluates the relationship between the pharmacokinetics of methotrexate (MTX), its efficacy in the treatment of rheumatoid arthritis (RA), and serum folic acid (FA) levels. The pharmacokinetics of MTX was studied in 29 patients with RA treated with low-dose MTX. The weekly dose of MTX was given orally at 2-4 mg every 12 h over a period of 24-36 h. Blood samples were taken 4 h after the first administration in any given week. A Bayesian method was used to estimate individual MTX pharmacokinetic variables. We then investigated the efficacy of MTX and the serum FA levels in these patients. We examined C-reactive protein levels (CRP) and the erythrocyte sedimentation rate (ESR), and analyzed the values obtained before and after MTX treatment in order to evaluate the efficacy of the MTX treatment. The degree of improvement in CRP and ESR was significantly correlated with the length of time the MTX concentration-time curve remained above 0.02 microM in one week. Furthermore, the degree of improvement in CRP was also significantly correlated with the area under the concentration-time curve (AUC) for MTX. These results suggest that serum MTX measurements could be useful in determining individual patient regimens.

In vitro and in vivo antifungal activities of TAK-456, a novel oral triazole with a broad antifungal spectrum.

TAK-456 is a novel oral triazole compound with potent and broad-spectrum in vitro antifungal activity and strong in vivo efficacy against Candida albicans and Aspergillus fumigatus. TAK-456 inhibited sterol synthesis of C. albicans and A. fumigatus by 50% at 3 to 11 ng/ml. TAK-456 showed strong in vitro activity against clinical isolates of Candida spp., Aspergillus spp., and Cryptococcus neoformans, except for Candida glabrata. The MICs at which 90% of the isolates tested were inhibited byTAK-456, fluconazole, itraconazole, voriconazole, and amphotericin B were 0.25, 4, 0.5, 0.13, and 0.5 microg/ml, respectively, for clinical isolates of C. albicans and 1, >64, 0.5, 0.5, and 0.5 microg/ml, respectively, for clinical isolates of A. fumigatus. Therapeutic activities of TAK-456 and reference triazoles against systemic lethal infections caused by C. albicans and A. fumigatus in mice were investigated by orally administering drugs once daily for 5 days, and efficacies of the compounds were evaluated by the prolongation of survival. In normal mice, TAK-456 and fluconazole were effective against infection caused by fluconazole-susceptible C. albicans at a dose of 1 mg/kg. In transiently neutropenic mice, therapeutic activity of TAK-456 at 1 mg/kg of body weight against infection with the same strain was stronger than those at 1 mg/kg of fluconazole. TAK-456 was effective against infections with two strains of fluconazole-resistant C. albicans at a dose of 10 mg/kg. TAK-456 also expressed activities similar to or higher than those of itraconazole against the infections caused by two strains of A. fumigatus in neutropenic mice at a dose of 10 mg/kg. These results suggest that TAK-456 is a promising candidate for development for the treatment of candidiasis and aspergillosis in humans.

Efficacy of TAK-457, a novel intravenous triazole, against invasive pulmonary Aspergillosis in neutropenic mice.

TAK-457 is an injectable prodrug of TAK-456, which is a novel oral triazole compound with potent antifungal activity. The in vivo efficacy of TAK-457 was evaluated in two models of invasive pulmonary aspergillosis with CDF(1) mice and CBA/J mice with transient neutropenia induced by cyclophosphamide. Against the infection in CDF(1) mice, treatment with 10 mg of TAK-457 and 1 mg of amphotericin B/kg reduced the fungal burden in lungs and rescued all mice. In the infection model with CBA/J mice, TAK-457 at a dose of 10 mg/kg significantly prolonged the survival time of mice, showing significant reduction of lung chitin levels and the plasma beta-D-glucan levels. On the other hand, amphotericin B at 1 mg/kg which was a maximum tolerable dose showed slight but not significant prolongation of survival time of mice, although it also reduced the lung chitin levels and the plasma beta-D-glucan levels to a lower extent but still significantly. These results suggest that TAK-457 is a promising candidate for development for the treatment of invasive aspergillosis in humans.