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Biomedical subjects

T L Wu

Publications and source records attributed to T L Wu.

At least 91 records · Page 5Linked to original sources
PubMed1986

Frequency of various congenital heart diseases in Chinese adults: analysis of 926 consecutive patients over 13 years of age.

A retrospective analysis was performed in 926 consecutive Chinese persons, aged 14 to 68 years, in whom congenital heart disease had been diagnosed and catheterization had been performed over the past 24 years. The incidence of various congenital cardiac malformations was compared with that in other series reported world-wide. About 60% of the 926 patients underwent surgery, and anatomic details of the malformations were examined. Congenital aortic valvular stenosis and coarctation of the aorta were uncommon (2.4% and 1.2%, respectively) among the Chinese adults, and the ethnic differences with Western countries in the incidence of these 2 defects were apparent and real. In contrast, aneurysm of the sinus of Valsalva, either ruptured or nonruptured, was more common (4.3%) and the incidence of outlet muscular type (or type 1) of ventricular septal defect was 4 to 9 times as common as has been reported in the West. Genetic differences rather than environmental factors or dietary habits may explain these special features.

Adolescent↗
PubMed1984

Subunit binding in the pyruvate dehydrogenase complex from bovine kidney and heart.

Binding of pyruvate dehydrogenase (E1) and dihydrolipoamide dehydrogenase (E3) to the isolated dihydrolipoamide acetyltransferase (E2) core of the pyruvate dehydrogenase complex from bovine heart and kidney was investigated with equilibrium, competitive binding, and kinetic methods. E2, which consists of 60 subunits arranged with icosahedral 532 symmetry, apparently possesses six equivalent, noninteracting binding sites for E3 dimers. It is proposed that each E3 dimer extends across 2 of the 12 faces of the E2 pentagonal dodecahedron. The equilibrium constant (Kd) for dissociation of E3 from E2 is about 3 nM, and the dissociation rate constant is about 0.057 min-1. For E1, Kd is about 13 nM, and the dissociation rate constant is about 0.043 min-1. Extensive phosphorylation of E1 (about three phosphoryl groups per E1 tetramer) increases Kd to about 40 nM.

Acetyltransferases↗
PubMed1984

Vectorcardiographic features of acute right ventricular infarction.

A total of seven patients with acute inferior or inferior-posterior transmural myocardial infarction who had cardiac scintigraphically confirmed right ventricular (RV) involvement was studied. Series of vectorcardiographic tracings were taken using the Frank lead reference system from the second day after onset of acute symptoms; we found that in patients with acute inferior and RV infarction, the magnitude of the planar ST vector was greater than or equal to 0.15 mV and the projection of the ST vector pointed either to the right-anterior or right-posterior direction in the horizontal (H) plane. The serial spatial ST vector changed its direction either: 1) from right-anterior-inferior octant to right-posterior-inferior octant or vice versa; or 2) from right-posterior-inferior octant to right-anterior-superior octant. The larger the magnitude of the rightward ST vector, especially right-anterior direction in the H plane, the greater the probability of acute RV infarction. In patients with acute inferior-posterior and RV infarction, the magnitude of the ST vector in the H plane was greater than or equal to 0.2 mV. The spatial ST vector pointed to the right-posterior-inferior octant and its direction did not change from the original octant in the serial tracings during the course of the acute stage. Our data suggest that vectorcardiography--a non-invasive, non-nuclear polluting, and economical method--has shown great potential to become, in the near future, the primary non-invasive diagnostic test of choice for acute RV infarction.

Adult↗
PubMed1984

Right ventricular ejection fraction. Validation of first-pass radionuclide studies by contrast angiography.

The accuracy of first-pass radionuclide angiocardiography (FPRNA) in the assessment of right ventricular ejection fraction (RVEF) using a multicrystal scintillation camera in the right anterior oblique view has not been reported. To test the validity of this technique, RVEFs derived from first-pass time-activity curves with and without background correction were compared with those obtained from contrast ventriculography in 36 patients. Background regions-of-interest tested included tricuspid valve, free wall, and horseshoe-shaped approaches. The tricuspid valve approach yielded a mean RVEF of 0.485 +/- 0.100 (SD) which slightly underestimated the contrast mean value (0.553 +/- 0.099, p less than 0.05) but correlated well (r = 0.88). The horseshoe approach yielded a mean value of 0.548 +/- 0.100 which approximated the contrast mean value and also correlated well (r = 0.81). The free wall approach yielded a mean of 0.502 +/- 0.095 which did not differ from contrast data (p greater than 0.05) but correlated less well (r = 0.77). With the method without background correction, a much lower mean value (0.387 +/- 0.081, p less than 0.01) and less correlation (r = 0.77) were obtained. Thus, FPRNA using a multicrystal camera in the right anterior oblique view is a reliable technique for measuring RVEF when a tricuspid valve or horseshoe-shaped background approach is employed, but is less accurate if the time-activity curve without background correction is applied.

Adolescent↗