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W Ko

Publications and source records attributed to W Ko.

At least 73 records · Page 4Linked to original sources
PubMed1987

Differences in diazepam pharmacokinetics in Chinese and white Caucasians--relation to body lipid stores.

We have compared diazepam pharmacokinetics in 16 Chinese and 18 white Caucasian healthy male volunteers, resident in Hong Kong and have correlated them with physical attributes. Serum concentrations of diazepam and desmethyldiazepam were measured in venous blood by an enzyme-linked immunoassay (0-3 h samples) and HPLC (3-72 h samples). Pharmacokinetic parameters were derived assuming a two compartment model, distribution phase less than 6 h, and 100% oral systemic availability. Compared with the Chinese the white Caucasians were older, heavier, taller, and fatter, as judged by skin fold thickness (SFT) and total body weight to 'Ideal' body weight (TBW/IBW) ratio; respective mean differences being 16%, 27%, 4%, 26%, and 15% (p less than 0.05). Mean diazepam apparent volume of distribution (V) and V/IBW were larger in the white Caucasians (52% & 39% respectively, p = 0.002). SFT and TBW/IBW ratio yielded the best correlations with V, V/TBW and V/IBW (0.50-0.75, p less than 0.05). Obesity indices contributed most to the overall regressions (R2 up to 0.52), and for V there was a further small effect (2%, partial F test) due to ethnic group, possibly reflecting stature. Mean peak diazepam concentration (Cmax) was similar in both ethnic groups. Time to Cmax (tmax) was more often prolonged in the Chinese (chi 2 test, p = 0.01). Body fat and stature may thus account for these inter-ethnic differences in the apparent volume of distribution of diazepam, a highly lipid-soluble drug.

Adult↗
PubMed1985

Herbal tea induced hepatic veno-occlusive disease: quantification of toxic alkaloid exposure in adults.

Four young Chinese women took daily doses of an unidentified 'Indian' herbal tea as treatment for psoriasis. Three (one of whom died), developed ascites, hepatomegaly and biochemical abnormalities within 19-45 days. The fourth patient discontinued herbal tea after 21 days when she developed a skin rash. Two patients had portal hypertension, while all had liver histology showing features of veno-occlusive disease. Pyrrolizidine alkaloids were identified spectrophotometrically in the brewed tea, and in the chopped leaves of the herbal mixture; the mean dose in the tea prepared for consumption being 12 mg/day of alkaloid base and 18 mg/day of N-oxide. The mean cumulative dose of alkaloids (base + N-oxide) before onset of symptoms (three patients), was estimated to be 18 mg/kg. In the asymptomatic patient with histological liver disease only, the corresponding dose was 15 mg/kg. These cases thus provide some measure of pyrrolizidine alkaloid toxicity in adults.

Adult↗
PubMedDate not supplied

Congential giant aneurysms of the left atrial appendage: diagnosis and management.

Giant congenital intrapericardial aneurysms of the left atrial appendage and body are unusual cardiac anomalies. Only 48 cases have been previously reported in the literature, with the vast majority presenting in otherwise healthy young patients. These can present clinically with persistent arrhythmias and progress to stroke if not diagnosed and treated. Our index case is that of a 34-year-old woman discovered to have a giant left atrial aneurysm who developed intermittent palpitations with sinus tachycardia. We present a review of the literature pertaining to their diagnosis, potential morbidity, and surgical management.

Adult↗
PubMedDate not supplied

Etiology of ventriculomegaly in choroid plexus papilloma.

In order to test the hypothesis that overproduction of cerebrospinal fluid can cause the hydrocephalus seen in choroid plexus papillomas, adult mongrel dogs with and without hydrocephalus were subjected to high pressure intraventricular infusions of artificial cerebrospinal fluid (CSF). Pre- and postinfusion volumes were calculated, using a new method for on-line measurement of ventricular volume involving linear measurements from Conray ventriculograms. Ventricular volumes increased an average of 8% in 36 h. The dogs previously made hydrocephalic by the intracisternal injection of kaolin had a significant volume increase (34% in 36 h). Overproduction of CSF alone can produce hydrocephalus, but the presence of hydrocephalus in choroid plexus papillomas is more likely to be a result of the complex interaction of CSF overproduction and partial restriction of CSF flow.

Animals↗