Effect of X-ray exposure on the pharmaceutical quality of drug tablets using X-ray inspection equipment.

CONTEXT: X-ray inspection equipment is widely used to detect missing materials and defective goods in opaque containers. Its application has been expanded to the pharmaceutical industry to detect the presence of drug tablets in aluminum foil press-through packaging. However, the effect of X-rays on the pharmaceutical quality of drug tablets is not well known. OBJECTIVE: In this study, the effect of X-rays on the pharmaceutical quality of drug tablets was investigated. METHODS: Exposure of acetaminophen, loxoprofen and mefenamic acid tablets to X-ray doses of 0.34 mGy (thrice the dose by X-ray scanning) to 300 Gy (maximum dose from our X-ray equipment) was demonstrated, and the samples were evaluated by formulation tests. RESULTS: Exposure to X-rays did not affect the pharmaceutical quality of the drug content. The samples exposed to X-rays exhibited almost the same profile in formulation tests (dissolution test, disintegrating test and hardness test) as control samples (0 Gy). The combination of X-ray exposure with accelerated temperature and humidity tests (six months) also did not affect the pharmaceutical quality. The color change of light-sensitive drugs (nifedipine and furosemide tablets) after X-ray exposure was negligible (< 1.0). In contrast, tablet color was remarkably changed by light from a D65 lamp. CONCLUSION: The X-ray scanning and X-ray exposure under our experimental conditions did not affect the pharmaceutical quality of drug tablets.

[Combination effect of pazufloxacin and anti-mrsa drugs against beta-lactam antibiotic induced vancomycin-resistant MRSA (BIVR)].

The in vitro combination effects of pazufloxacin (PZFX) with an anti-MRSA drug such as vancomycin (VCM), teicoplanin (TEIC), arbekacin (ABK), minocycline (MINO), rifampicin (RFP) and sulfamethoxazole-trimethoprim (ST) were investigated against 26 strains of beta-lactam antibiotic induced vancomycin-resistant MRSA (BIVR) by the checkerboard method. The additive and synergistic effects were observed with the combination of PZFX and VCM (50%, 13/26 strains), PZFX and TEIC (96%, 25/26 strains), PZFX and ABK (65%, 17/26 strains), PZFX and MINO (46%, 12/26 strains), PZFX and ST (54%, 14/26 strains). The synergistic effects were observed with the combination of PZFX and TEIC (4%, 1/26 strains), PZFX and ABK or MINO (15%, 4/26 strains). The antagonistic effects were observed with only PZFX and MINO (12%, 3/26 strains), others were all indifference.

Investigation of beta-lactam antibiotic-induced vancomycin-resistant MRSA (BIVR).

We could not detect hetero-vancomycin-intermediate resistant Staphylococcus aureus (hetero-VISA), according to the definition of hetero-VISA, from the clinical isolates of 140 methicillin-resistant S. aureus (MRSA) strains. However, 15 beta-lactam antibiotic-induced vancomycin-resistant MRSA (BIVR) strains were detected from the same strains. We screened 1882 MRSA clinical isolates obtained in 2002 from 21 institutes throughout Japan. The detection rate of blood-isolated BIVR was 12.6% (19/151), and that of nonblood-isolated BIVR was 4.9% (85/1731; P < 0.001; chi2 test). Uridine-diphosphate-N-acetylmuramyl-L: -alanyl-D: -isoglutamyl-L: -lysine, used as the peptidoglycan material of S. aureus, showed the same results as beta-lactam antibiotics in BIVR.