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Biomedical subjects

F Miranda

Publications and source records attributed to F Miranda.

At least 55 records · Page 3Linked to original sources
PubMed1976

Purification of six neurotoxins from the venom of Dendroaspis viridis. Primary structure of two long toxins.

Six neurotoxins were purified from Dendroaspis viridis venom using gel filtration and equilibrium chromatography. The amino acid sequences of two of these neurotoxins (72 and 73 residues, five disulphide bridges) have been determined using almost exclusively automated Edman degradation. These two sequences are very similar: the only differences lies in the presence of one extra glycine at the C-terminal end of one of them. There is a good homology with the sequences of toxins now isolated from other Elapidae and Hydrophidae venoms.

Amino Acid Sequence↗
PubMed1976

Absence of relationships between L-dopa plasma levels and therapeutic effect in Parkinson's disease treated with L-dopa.

The plasma concentration of dopa was studied in 15 parkinsonian patients after a single administration of L-dopa. The study was undertaken in order to determine if correlation between plasma dopa concentration and clinical performance as a result of the tests carried out before and after a single dose of dopa, was present. Our data confirm the absolute absence of correlation between dopa levels in plasma and clinical improvement during long-term treatment. Moreover, clinical responses to the performance tests were not related to the concentration of circulating L-dopa in the plasma. Therefore dopa levels cannot be useful in clinical practice but only for the prevention of too high concentrations of plasma L-dopa which often cause a few side-effects.

Administration, Oral↗
PubMed1975

Amino-acid sequence of toxin III of Naja haje.

The complete amino acid sequence of toxin III of Naja haje (72 residues) has been established mainly by use of a protein sequenator (identification of 70 residues). The two C-terminal residues have been determined by digestion with carboxypeptidases A and B. Addition of succinylated protein or peptide greatly improved the performance of the sequenator for the Edman degradation of peptides: on one peptide (39 residues) degradation went to step 34 with a protein program and on two peptides (10 and 13 residues) degradation reached the last amino acid with a peptide program (use of dimethylbenzylamine). Amino acid analysis of tryptic peptides obtained by digestion of the C-terminal cyanogen bromide peptide are in full agreement with the sequence established by automatic degradation. The sequence of toxin III of Naja haje is unique and is very similar to that of Naja nivea alpha (although there are 9 differences), of Naja melanoleuca b (11 differences) and also to that of Naja naja A (18 differences).

Amino Acid Sequence↗
PubMed1975

Synthesis of apamin, a neurotoxic peptide from bee venom.

The apamin sequence has been synthesized by the solid-phase procedure. The synthetic peptide showed the same physiochemical and chemical properties as natural apamin in the following tests: paper electrophoresis, amino acid analyses after acid and enzymatic hydrolyses, sequence analysis, electrophoreses after tryptic and chymotryptic digestions. Synthetic apamin was as active as natural apamin in the neurotoxic assay in mice (LD50, after subcutaneous injection, for the 20-g mouse: 58 mug).

Amino Acid Sequence↗