PubMed Health⌕ Search

Biomedical subjects

L K Siu

Publications and source records attributed to L K Siu.

40 records · Page 3Linked to original sources
PubMed1998

Evaluation of a selective transport medium for gastric biopsy specimens to be cultured for Helicobacter pylori.

Since the means of culturing Helicobacter pylori may not be available in some laboratories, prolonging the survival of this organism during transportation is a major concern in terms of improving detection rates. A selective transport medium was evaluated for the preservation of H. pylori from 254 gastric biopsy specimens collected from a rural area in China where culturing is not feasible. Gastric biopsy specimens were inoculated in sterile broth consisting of brain heart infusion (BHI) broth, horse serum, and yeast extract supplemented with vancomycin, amphotericin B, and nalidixic acid (VAN). Of the 254 biopsy specimens, 238 were identified by histology to have H. pylori infection. Total rates of recovery of H. pylori from the H. pylori-positive gastric biopsy specimens stored in the BHI-VAN broth ranged from 76 to 46% after storage of specimens for 5 to 9 days. In conclusion, the selective medium is useful for prolonging the survival of H. pylori in gastric biopsy specimens for which immediate culture is not feasible.

Adult↗
PubMed1998

Correlation of in vitro susceptibility testing results for amoxicillin-clavulanate and ampicillin-sulbactam using a panel of beta-lactamase-producing Enterobacteriaceae.

Correlation between in vitro susceptibility results for amoxicillin-clavulanate (AMC) and ampicillin-sulbactam (SAM) was studied using 136 clinical and control strains of Enterobacteriaceae harboring TEM-1, SHV-1 or OXA-1-like beta-lactamases. Determination of minimal inhibitory concentration of antibiotics was performed by agar dilution. The beta-lactamases were initially characterized using isoelectric focusing. Further identification was done by DNA hybridization with or without prior PCR amplification. All strains sensitive to SAM were found to be sensitive also to AMC. In contrast, among those susceptible to AMC, only 50% were sensitive to SAM while 36% gave intermediate results and 14% were resistant. Major differences were found solely among SHV-producers while minor differences occurred mostly among TEM-producers. This phenomenon is probably related to the differential activities of clavulanate and sulbactam against various beta-lactamases. In conclusion, testing of Enterobacteriaceae isolates for susceptibility to AMC and SAM should be performed and reported individually to avoid erroneous designation of susceptibility.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed1993

Single-dose pharmacokinetics of intraperitoneal ofloxacin in patients on continuous ambulatory peritoneal dialysis.

The present study examines the pharmacokinetics of ofloxacin given in a single dose of 200 mg intraperitoneally (ip) in the first bag of three 2-L 8-hour exchanges. Ofloxacin was measured using high-pressure liquid chromatography (HPLC) in the serum and peritoneal effluent over 24 hours. Six patients without and 3 patients with peritonitis were studied. Ofloxacin given ip was almost completely absorbed after an 8-hour dwell, and this was not affected by peritonitis. The time required to reach peak serum concentration was longer than that reported previously following oral administration. Elimination half-life (T1/2) of ofloxacin was markedly prolonged compared to patients with normal renal function. Peritoneal clearance accounted for only one-tenth of total serum clearance. Peritonitis appeared to shorten the T1/2 of ofloxacin, but this was mainly due to an increase in total serum clearance rather than a change in peritoneal clearance. Peritoneal drug concentration > 0.5 mg/L was reached in the second and third exchange by the second hour. No side effects from ip ofloxacin were observed. We concluded that ofloxacin given in a single dose of 200 mg is safe and provides adequate therapeutic serum and peritoneal concentration for more than 24 hours in patients on continuous ambulatory peritoneal dialysis (CAPD) with 8-hour exchanges.

Aged↗