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R Bald

Publications and source records attributed to R Bald.

77 records · Page 5Linked to original sources
PubMed1973

Identification of chloramphenicol-binding protein in Escherichia coli ribosomes by affinity labeling.

Monoiodoamphenicol, a synthetic analogue of chloramphenicol, has been shown by competition experiments with chloramphenicol and lincomycin to bind at the same site of 70S ribosomes as chloramphenicol. At - 2 degrees it forms a 1:1 complex with 70S ribosomes having a value of K (7.5 x 10(4) M(-1)) that is one order of magnitude lower than that of chloramphenicol. At 37 degrees , monoiodoamphenicol irreversibly inhibits the protein-synthesizing activity of E. coli ribosomes. It is shown that the analogue reacted preferentially with protein L16 of E. coli 70S ribosomes, and we therefore conclude that protein L16 belongs to the chloramphenicol-binding site of E. coli ribosomes. Since the chemically reactive group of monoiodoamphenicol resembles iodoacetamide, the reaction of E. coli 70S ribosomes with monoiodoamphenicol was compared to that with iodoacetamide. Iodoacetamide did not react with protein L16, but it predominantly reacted with proteins S18 of the 30S subunit. Furthermore, monoiodoamphenicol was reacted with E. coli ribosomal subunits. Isolated 50S subunits bound monoiodoamphenicol by about one order of magnitude less than 70S ribosomes. Again, protein L16 reacted with the affinity label. Monoiodoamphenicol reacted with protein S18 in isolated 30S subunits; it also bound to 70S ribosomes of Bacillus stearothermophilus, however, it did not bind irreversibly to these 70S ribosomes.

Acetamides↗
PubMedDate not supplied

Flow analysis in the pulmonary trunc in fetuses with tetralogy of Fallot by colour Doppler flow mapping; two case reports.

Prenatal diagnosis of tetralogy of Fallot by two-dimensional echocardiography, which is based on demonstration of a ventricular septal defect and a large overriding aorta, is difficult. In the majority of cases the main pulmonary artery is small. In utero, there is no pathologically increased degree of the physiological right-ventricular hypertrophy. Colour Doppler flow mapping of reverse flow from the descending aorta via the ductus arteriosus into the main pulmonary artery is easily demonstrated, and provides an indirect sign of severe right-ventricular outlet obstruction. The technique also differentiates between pulmonary stenosis and atresia; the stenotic jet, even small, is identified by demonstration of high velocities and turbulences in the main pulmonary artery.

Adult↗
PubMedDate not supplied

[De Barsy-Moens-Dierckx syndrome: unusual course in a neonate].

We report about a premature infant with a De Barsy-Moens-Dierckx-syndrome, which is a rare cutaneo-oculo-cerebral malformation-syndrome. It is defined by the combination of a progeroid aspect, cutis laxa, growth retardation, cornea clouding, mental retardation and athetoid movements. Furthermore, the reported case showed a remarkable thermolability and suffered from generalised seizures resistant to therapy. Despite extensive sonographic examinations the prepartal diagnosis seems to be very difficult.

Abnormalities, Multiple↗