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P Maly

Publications and source records attributed to P Maly.

44 records · Page 3Linked to original sources
PubMed1983

Identification of tyrosine residues that are susceptible to lactoperoxidase-catalyzed iodination on the surface of Escherichia coli 30S ribosomal subunit.

The detailed surface topography of the Escherichia coli 30S ribosomal subunit has been investigated, with iodination catalyzed by immobilized lactoperoxidase as the surface probe. Under mild conditions, only proteins S3, S7, S9, S18, and S21 were iodinated to a significant and reproducible extent. These proteins were isolated from the iodinated subunits, and in each case, the individual tyrosine residues that had reacted were identified by standard protein sequencing techniques. The targets of iodination that could be positively established were as follows: in protein S3 (232 amino acids), the tyrosines at positions 167 and 192; in S7 (153 amino acids), tyrosines 84 and 152; in S9 (128 amino acids), tyrosine 89; in S18 (74 amino acids), tyrosine 3 (tentative); in S21 (70 amino acids), tyrosines 37 and 70. The results represent part of a broader program to investigate ribosomal topography at the amino acid-nucleotide level.

Amino Acid Sequence↗
PubMed1980

Precise localization of the site of cross-linking between protein L4 and 23S ribonucleic acid induced by mild ultraviolet irradiation of Escherichia coli 50S ribosomal subunits.

Mild ultraviolet irradiation of Escherichia coli 50S ribosomal subunits causes a cross-linking reaction between protein and RNA, whose primary target is protein L4 [Möller, K., & Brimacombe, R. (1975) Mol. Gen. Genet. 141, 343]. Here we have determined the site of this cross-link both on L4 and on 23S RNA. For the site on the protein, a cross-linked protein-oligonucleotide complex was isolated and subjected to successive digestions with various proteases. In each case the peptide-oligonucleotide complexes formed were analyzed. It could clearly be shown that the cross-link site was contained within a characteristic peptide 16--20 amino acids long and that the amino acid concerned was the tyrosine residue at position 35 in the recently completed L4 sequence (M. Kimura and B. Wittmann-Liebold, personal communication). For the site on the RNA, a cross-linked L4--23S RNA complex was subjected to mild nuclease digestion, producing a range of L4--RNA fragments which were isolated with the help of a new two-dimensional gel electrophoresis system. Oligonucleotide analyses of these fragments, combined with successive nuclease digestions of the residual oligonucleotide attached to protein L4, established that the site of cross-linking was homogeneous, involving a uridine residue at position 615 in the recently determined 23S RNA sequence [Brosius, J., Dull, T. J., & Noller, H. F. (1980) Proc. Natl. Acad. Sci. U.S.A. 77, 201].

Amino Acid Sequence↗
PubMed1978

[Magnification technique in abdominal angiography (author's transl)].

The authors describe the requirements for improved information with magnification in abdominal angiography. The low effect of the microfocus tube limits its use in conventional technique mainly because of the grid. Magnification technique combined with high sensitive screens and no grid will compensate for the low effect of the tube. Unsharpness due to motion is more marked with magnification technique but is in practical work of little importance. A useful technique for renal and pancreatic angiography is discussed.

Angiography↗
PubMed1978

[Resolution of small vessels in abdominal magnification angiography (author's transl)].

In order to assess the resolution of small vessels in abdominal magnification angiography, the influence of iodine concentration and magnification ratio was analyzed in a model experiment using 0.1 mm focus and lanthanoxibromide screens MR 600. The experiment showed that the resolution increases with both increasing magnification ratio and iodine concentration. Assuming that there was no movement of the object, the vessels of 80 micrometer could be resolved in three- to five-fold magnification.

Abdomen↗
PubMed1978

[Radiation dose in renal magnification angiography compared with conventional angiography (author's transl)].

Measurements of skin dose, integrated skin dose area, and integral dose in combined conventional and magnification renal angiography using lanthanoxibromide screens MR 600 and carbon fibre plate in filmchangertop have been made. The mean skin dose in magnification technique was 0.56 rad./film with focus-skin distance of 35 cm, FFD 1 m, 85-90 kV and sagittal diameter of abdomen of 20 cm. The combination of angiographic technique with and without magnification and the use of a high-sensitivity receiving unit makes it possible to keep the total skin dose per investigation (8.5 rad.) within the limits accepted in conventional abdominal angiography.

Angiography↗
PubMedDate not supplied

Comparison between EEG and observation of rabbit behaviour in evaluation of subarachnoid neurotoxicity of metrizamide.

The non-ionic contrast medium metrizamide (370 mg I/ml) was injected into the cisterna magna of rabbits at 2 dose levels (0.1 ml/kg and 0.5 ml/kg) to investigate whether visually evaluated EEG can detect neurotoxicity at a lower dose level than a method based on observation and ranking of signs of excitation and depression in animal behaviour. Half of the metrizamide injections were made without anaesthesia, whereas the remaining injections were made during a short alphadolon/alphaxolon anaesthesia. EEG and animal behaviour were followed for 24 h after the injection of metrizamide. At the low 'clinical' dose, EEG could not detect statistically significant neurotoxicity, neither in anaesthetized nor in non-anaesthetized rabbits. Observation of animal behaviour, however, could detect statistically significant signs of depression in animals that had been anaesthetized. At the high dose level, both methods could detect significantly more serious symptoms of neurotoxicity than at the low dose level.

Anesthetics↗