ABSTRACT
The quantity and concentration of major allergens in mite allergenic extracts are crucial for skin testing, which is the recommended standard method for the diagnosis of house dust mite allergic disease. The purposes of this study were 1) To compare the constituents of major mite allergens in 3 types of mite extracts, i.e., extracts from mite reared in-house (Dermatophagoides pteronyssinus and Dermatophagoides farinae), extracts from commercial mite products and commercial ready-made mite extracts. These in-house extracts were prepared either with or without the preservative, glycerine. The concentrations of the major constituents of group 1 and 2 allergens of the extracts were determined by a two-site monoclonal based ELISA. 2 ) Biological assays were also carried out to determine the relative potency of the extracts in 120 allergic patients by skin prick test. It was found that the mean concentrations of Der p1, Der f1 and group 2 mite allergens in extracts from mites reared in-house were 102, 195 and 94 ตg/ml, respectively, compared to 169, 238 and 91 ตg/ml, respectively in commercial mite extracts. The commercial with product had the lowest concentrations of mite allergens (1 ตg/ml). Comparison of mite extracts with and without glycerine preservative showed no significant difference in concentrations of major allergens. Reduction of allergens concentration from 10,000 to 1,000 PNU/ml also reduced the concentration of mite allergen proportionately. Siriraj mite extracts were stable for at least 1 year at 4 oC without any significant change in composition or concentration. In conclusion, mite reared in-house can be used as raw material for preparation of mite allergenic vaccine.
ABSTRACT
Oral bioavailability of single dose of 500 mg Rancil capsule manufactured by Ranbaxy Co., Ltd., which was the generic amoxicillin used in Siriraj Hospital, was compared to that of 500 mg capsule of the reference (original) amoxicillin, i.e., Amoxil-Bencard manufactured by Smith-Kleine & Beecham Inc., using randomized cross-over design. The study was done in 12 healthy volunteers,7 males and 5 females, aged 23-51 years weighing 46-65 kg. Venous blood sampling was taken from each subject prior to and at 0.5, 1, 2, 4, 6 and 8 hr after drug administration. Serum concentrations of amoxicillin were assayed by high performance liquid chromatography (HPLC). Maximum serum concentrations (Cmax) and areas under serum concentration-time curves(AUCs) of both Rancil and Amoxil-Bencard were analysed and compared. The Cmax and AUCs values of Rancil and Amoxil-Bencard were statistically equivalent, i.e., 8.67 ฑ 1.50 ตg/ml v.s. 9.36 ฑ 1.62 mg/ml respectively (p = 0.069) for Cmax ; and 26.02 ฑ 6.80 ตg.hr/ml v.s. 27.51 ฑ 8.52 ตg.hr/ml respectively (p=0.355) for AUC0-8 hr. The 90 % confidence intervals of the Cmax ratio and AUC0-8 hr ratio between Rancilฎ and Amoxil-Bencardฎ were 0.90-1.02 and 0.87-1.11 respectively which were within the acceptable equivalent range of 0.8 - 1.25. Thus, Rancilฎ is considered bioequivalent to and can be used interchangeably with Amoxil-Bencardฎ in clinical infections requiring amoxicillin in order to minimize the cost of treatment.