Pharmacokinetics of Amitriptyline Demethylation;A Crossover Study with Single Doses of Amitriptyline and Nortriptyline

A single dose crossover pharmacokinetic study of amitriptyline and nortriptyline was done to find out the extent of first-pass metabolism to nortriptyline after amitripyline administration, and the contribution of nortriptyline during amitriptyline therapy. Six healthy male volunteers took part in this study and were given single doses (50 mg) of amitriptyline and nortriptyline at more than three-week intervals. Plasma concentrations of the drugs were measured up to 48 hours. Total area under the plasma concentration-time curve (AUe) of amitriptyline (744.6±258.4 ng/ml·hl was smaller than that of nortriptyline (l497.3±589.8 ng/ml'h), and the mean terminal half-life of amitriptyline (21.8±3.9 hr) was shorter than that of nortriptyline (36.8±5.9 h). The total area under the plasma concentration-time curve of nortriptyline produced by amitriptyline administration was 498.1 ±274.5 ng/ml·h, and the fraction produced by the first-pass of amitriptyline was 33.7 ± 10.5%. From this data, it can be estimated that the average nortriptyline concentration could be about 40% of the total tricyclic antidepressants present in the plasma of patients taking multiple amitriptyline therapy at steady state. About 34% of nortriptyline is produced by first- pass effect during gastrointestinal absorption of amitriptyline to systemic circulation resulting from N-demethylation of amitriptyline in the liver. Then, the rest of the nortriptyline is formed continuously at a rate proportional to the rate of amitriptyline elimination

Pengaruh Ekstrak Jahe Merah (Zingiber Officinale Roscoe Var. Rubrum) Terhadap Kadar Mda Serum Tikus Setelah Terpapar Asap Rokok

Latar Belakang: Asap rokok merupakan salah satu sumber radikal bebas. Kadar radikal bebas yang tinggi dapat menyebabkan terjadinya kondisi stres oksidatif dan memicu terjadinya peroksidasi lipid pada membran sel yang akan menghasilkan Malondialdehyde (MDA). Sebenarnya, tubuh mempunyai sejumlah enzim dan zat yang dapat menetralkan radikal bebas yang disebut antioksidan. Kadar radikal bebas yang tinggi dapat menyebabkan antioksidan endogen tidak mampu untuk menetralisir. Kemampuan jahe sebagai antioksidan alami juga tidak terlepas dari kadar komponen fenolik total yang terkandung di dalamnya sehingga memiliki efek protektif yang tinggi dalam menangkal stres oksidatif. Tujuan: Penelitian ini bertujuan untuk mengetahui pengaruh pemberian ekstrak jahe merah terhadap kadar MDA serum tikus setelah terpapar asap rokok. Metode: Penelitian ini merupakan penelitian true experimental dengan desain pre-post test only control group design pada tikus. Perlakuan yang diberikan yaitu dengan pemberian ekstrak jahe merah (Zingiber officinale var. Rubrum) dan pemberian paparan asap rokok pada tikus, sedangkan keluarannya (outcome) adalah kadar MDA serum tikus. Hasil: Pemberian paparan asap rokok pada kelompok 2 meningkatkan kadar MDA serum dibandingkan dengan kelompok 1. Kelompok 3 yang diberikan ekstrak jahe merah 200 mg/kgBB/hari tidak efektif menurunkan kadar MDA serum. Pemberian ekstrak jahe merah menurunkan kadar MDA serum setelah diberikan paparan asap rokok (K4) jika dibandingkan dengan kelompok yang diberikan jahe merah tanpa diberikan paparan asap rokok (K3), penurunan tersebut tidak bermakna secara statistik. Kelompok 4 meningkatkan kadar MDA serum tikus dibandingkan dengan kelompok 2. Kesimpulan: Tidak terdapat pengaruh yang bermakna dari pemberian jahe merah (Zingiber officinale var. Rubrum) terhadap kadar MDA darah tikus setelah terpapar asap rokok

The current capacity and quality of colonoscopy in Korea

Background/Aims Little is known for the capacity and quality of colonoscopy, and adherence to colonoscopy surveillance guidelines in Korea. This study aimed to investigate the present and potential colonoscopic capacity, colonoscopic quality, and adherence to colonoscopy surveillance guidelines in Korea. Methods We surveyed representative endoscopists of 72 endoscopy units from June to August 2015, using a 36-item questionnaire regarding colonoscopic capacity, quality, and adherence to colonoscopy surveillance guidelines of each hospitals. Results Among the 62 respondents who answered the questionnaire, 51 respondents were analyzed after exclusion of 11 incomplete answers. Only 1 of 3 of endoscopy units can afford to perform additional colonoscopies in addition to current practice, and the potential maximum number of colonoscopies per week was only 42. The quality of colonoscopy was variable as reporting of quality indicators of colonoscopy were considerably variable (29.4%–94.1%) between endoscopy units. Furthermore, there are substantial gaps in the adherence to colonoscopy surveillance guidelines, as concordance rate for guideline recommendation was less than 50% in most scenarios. Conclusions The potential capacity and quality of colonoscopy in Korea was suboptimal. Considering suboptimal reporting of colonoscopic quality indicators and low adherence rate for colonoscopy surveillance guidelines, quality improvement of colonoscopy should be underlined in Korea