Biomedical subjects

Richard Chua

Publications and source records attributed to Richard Chua.

3 recordsLinked to original sources

PubMed2004

Quality, labeling accuracy, and cost comparison of purified soy isoflavonoid products.

OBJECTIVES: To evaluate the labeling accuracy and product uniformity of available soy isoflavone products in the eastern Washington State region for 13 products and to perform a cost comparison based on the isoflavone content in milligrams for 11 products. DESIGN: Thirteen (13) isoflavone products (7 tablet and 6 capsule formulations) were randomly obtained from health food, grocery, and pharmacy outlets in eastern Washington State. Four different samples of the same product were extracted using 75% ethanol. Each sample was analyzed for isoflavone content using a gradient high-performance liquid chromatography (HPLC) method. Pure isoflavonoid standards were used to quantify the content of genistein, daidzein, and glycitein and their respective glycosides. The amount of total isoflavonoids per purchased product was then divided into its purchase price in order to make cost comparisons between the products based on a 50 mg/d dose. RESULTS: The weight variation within each product was generally small (<4%). However, there was significant variability in the composition of the products. Only 4 of the 13 products contained at least 90% of the isoflavone content claimed on the label and 2 of products contained impurities in the HPLC chromatogram that exceeded 40%. There was no difference in the total isoflavonoid contents of the 2 identical products made by the same manufacturer, but the percentages of the main components had changed significantly over time. Based on a 50-mg isoflavone per day dose, the cost of a 30-day supply ranged from $3.20 to $65.88. CONCLUSION: There is a lack of uniformity among the products tested and the majority (67%) of the products contained less than 90% of labeled amounts. There is significant variability in the compositions between the products and in the composition of the same product over time. Consumers cannot trust isoflavonoid product labels to represent the product's content accurately or that product pricing is a reflection of isoflavone content.

Chromatography, High Pressure Liquid↗

PubMed2003

Teleneurology by email.

We introduced an email teleneurology service for patients referred to a neurologist by general practitioners. Over 14 months, 76 referrals (of 75 patients) were received. To determine the sustainability of the service, we studied a second cohort of 76 consecutive patients referred after our first study. We also followed up the first cohort of patients to get information on longer-term safety. The second cohort was obtained in one month less than the first, and had similar characteristics in terms of age, sex and the time taken by the neurologist to reply to the general practitioner. It contained fewer patients requiring clinic appointments (34% versus 43%). Fewer patients from the second cohort were referred for second opinions (4 versus 10) and there were no resulting changes in diagnosis. Follow-up of the first cohort from a mean of 6 months to a mean of 23 months led to seven more re-referrals and no additional changes in diagnosis. We conclude that teleneurology by email is sustainable for this group of patients, and confirm that it is safe, effective and efficient.

Adult↗

PubMed2002

Telemedicine for new neurological outpatients: putting a randomized controlled trial in the context of everyday practice.

In a retrospective review, the telemedical management of 65 outpatients from a randomized controlled trial (RCT) of telemedicine for non-urgent referrals to a consultant neurologist was compared with the management of 76 patients seen face to face in the same trial, with that of 150 outpatients seen in the neurology clinics of district general hospitals and with that of 102 neurological outpatients seen by general physicians. Outcome measures were the numbers of investigations and of patient reviews. The telemedicine group did not differ significantly from the 150 patients seen face to face by neurologists in hospital clinics in terms of either the number of investigations or the number of reviews they received. Patients from the RCT seen face to face had significantly fewer investigations but a similar number of reviews to the other 150 patients seen face to face by neurologists (the disparity in the number of investigations may explain the negative result for telemedicine in that RCT). Patients with neurological symptoms assessed by general physicians had significantly more investigations and were reviewed significantly more often than all the other groups. Patients from the RCT seen by telemedicine were not managed significantly differently from those seen face to face by neurologists in hospital clinics but had significantly fewer investigations and follow-ups than those patients managed by general physicians. The results suggest that management of new neurological outpatients by neurologists using telemedicine is similar to that by neurologists using a face-to-face consultation, and is more efficient than management by general physicians.

Adolescent↗