Biomedical subjects

M B Liu

Publications and source records attributed to M B Liu.

4 recordsLinked to original sources

PubMed2006

Autoantibody against beta1-adrenergic receptor and left ventricular remodeling changes in response to metoprolol treatment.

Autoantibodies specific for the beta(1)-adrenoceptor (beta(1)-AR) have been implicated in the pathology of congestive heart failure (CHF). We hypothesized that the presence of autoantibodies against beta(1)-AR (anti-beta(1)-AR) is associated with left ventricular (LV) remodelling in response to metoprolol. Synthetic beta(1)-AR peptides served as the target antigen in an ELISA (enzyme-linked immunosorbent assay) were used to screen the sera of 106 CHF patients. Patients were separated into positive (+) anti-beta(1)-AR or negative (-) anti-beta(1)-AR groups according to their anti-beta(1)-AR reactivity. Echocardiography (ECG) was performed at baseline and after one year of metoprolol therapy in combination with standard treatment regime for CHF, that is, digoxin, diuretics and an ACEI (angiotensin-converting enzyme inhibitor). The dose of metoprolol was doubled on a biweekly basis up to 50 mg x 2 daily (b.i.d./day) or attainment of maximum tolerated dose. Ninety-six patients completed final data analysis. Fifty-four patients with (+) anti-beta(1)-AR had greater improvements than 42 patients with (-) anti-beta(1)-AR in LVEDD (left ventricular end-diastolic dimension) (P < 0.01, from 69 +/- 0.8 to 58.0 +/- 0.5 mm vs. 69.0 +/- 0.8-63.6 +/- 0.9 mm) and LVESD (left ventricular end-systolic dimension) (P < 0.01, from 57.1 +/- 1.4 to 43.9 +/- 0.8 mm vs. 56.2 +/- 0.9-48.6 +/- 1.0 mm), and LVEF (left ventricular ejection fraction) (P < 0.01, from 35.4 +/- 1.3 to 49.8 +/- 0.6% vs. 34.4 +/- 1.0-44.3 +/- 1.1%) by metoprolol therapy in combination with standard treatment regime for one year. Of the CHF patients with (+) anti-beta(1)-AR, 65.4% responded to target metoprolol dose as compared to 21.4% of CHF patients without anti-beta(1)-AR (P < 0.01). Response to target metoprolol dose occurred more rapidly in (+) anti-beta(1)-AR than (-) anti-beta(1)-AR of CHF patients (67.5 +/- 2.4 vs. 100.8 +/- 3.0 days, P < 0.01). These results demonstrated that CHF patients with (+) anti-beta(1)-AR had greater improvements in LV remodelling and heart function by metoprolol as compared to (-) anti-beta(1)-AR patients. Moreover, patients with (+) anti-beta(1)-AR have better tolerance to metoprolol therapy than patients without anti-beta(1)-AR.

Adrenergic beta-Antagonists↗

PubMed1989

Renal abnormalities in schoolchildren.

To establish prevalence of some renal abnormalities in schoolchildren, an epidemiologic study of 132,686 schoolchildren, including 69,903 boys and 62,783 girls, was conducted from March 1987 to May 1988 in the city of Taipei. At the health station of each school, the students were screened quickly by a physician with portable real-time ultrasound equipment. When a renal abnormality was detected or suspected, the examinee was referred to Taipei Municipal Women and Children's Hospital for further investigation. Radiologic and urologic procedures were then selectively performed to establish the correct diagnosis. Renal abnormalities were detected in 645 students (approximately 0.5% of total population screened). There were 256 cases of hydronephrosis, 103 cases of unilateral renal agenesis, 128 cases of unilateral small kidney, 90 cases of renal cystic disorders, 30 cases of ectopic kidney, and 38 cases of other abnormalities. Surgically correctable lesions were demonstrated in 50 of these students. Rapid renal ultrasonography was found to effectively detect some renal abnormalities initially, and prevalence could then be established after further investigations.

Adolescent↗

PubMed1981

A rapid method to produce anti-gentamicin antibody.

The aminoglycoside antibiotic, gentamicin, was conjugated to erythrocytes or bovine serum albumin (BSA) by a simple procedure in which ECDI was employed as the coupling reagent. When rabbits were immunized by injecting gentamicin-goat erythrocyte conjugates, three kinds of antibody were produced: 1. anti-gentamicin antibody, 2. anti-ECDI antibody, 3. goat erythrocyte agglutinins. The interfering anti-ECDI antibody was easily neutralized by adding acidified ECDI solution to the immune serum. Goat agglutinins were avoided by employing rabbit erythrocytes as the carrier cell in the hemagglutination titration. Highly specific anti-gentamicin antiserum was produced in rabbits by first injecting an initial dose of gentamicin-BSA conjugate as an emulsion in incomplete Freund's adjuvant via the foot pad, followed by multiple intravenous injections of gentamicin-erythrocyte conjugates. The immunization took approximately 21 days. High titered anti-gentamicin antibody was also produced by foot pad inoculation of gentamicin-BSA conjugates; however, the time necessary to achieve comparable titers was considerably longer (55 days). The antibodies produced by both immunization procedures were mainly of the IgG class.

Animals↗

PubMed1977

Mutagenicity of benzidine and related compounds employed in the detection of hemoglobin.

Seven compounds commonly used as chromagens for the detection of hemoglobin and its derivatives have been assayed for mutagenicity employing the Salmonella/mammalian microsome test. Three of these compounds, benzidine, o-dianisidine, and o-tolidine, were shown to be mutagenic. Since benzidine and o-tolidine are already known to be carcinogens, there is a high probability that o-dianisidine will also prove to be a carcinogen. Four compounds tested with this system, o-anisidine, diphenylamine, guaicol, and o-toluidine, were not mutagenic.

Animals↗