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D Biral

Publications and source records attributed to D Biral.

27 records · Page 2Linked to original sources
PubMed1987

Biochemical and immunologic studies in a case of congenital myopathy with unusual morphologic features.

Mitochondria and myosin were isolated from a muscle biopsy of a 9-year-old boy with an unusual congenital myopathy characterized by type I fiber uniformity, jagged Z-line, and transverse network hypertrophy of mitochondria. Biochemical examination of isolated mitochondria showed that only citrate synthase activity was significantly reduced. Electrophoresis of myosin heavy chains and immunoenzymatic analysis of myosin heavy and light chains with antibodies specific to either fast or slow myosins showed that only the slow-type isoform of myosin was detectable. Indirect immunofluorescence of muscle biopsy showed that all muscle fibers homogeneously expressed only the slow type of myosin.

Child↗
PubMed1985

Slow myosin heavy chain isozyme in nemaline myopathy.

Muscle biopsies from two sporadic cases of congenital nemaline myopathy were examined for myosin heavy chain composition. Electrophoresis of congenital nemaline myopathy (CNM) muscle myosin in SDS-5% polyacrylamide gels gave rise to a single heavy chain band, with a migration rate and antigenic properties identical to that of the adult slow form, as demonstrated by Western blot techniques and by using specific antibody. Immunofluorescent studies indicate that CNM muscle fibers, including the most severely atrophic fibers, are homogeneous with respect to myosin heavy chain composition.

Adult↗
PubMed1984

Myosin subunit composition in human developing muscle.

Previous pyrophosphate-gel studies have reported the existence of embryonic neonatal myosin isoenzymes in human developing muscle. The present investigation was undertaken to characterize their subunit composition more precisely. Two immature muscle myosins are contrasted with adult myosin: neonatal myosin and foetal myosin. The neonatal form of myosin is weakly cross-reactive with rabbit slow myosin and contains only fast-type light chains (LC), LC1F and LC2F. The associated heavy chains consist of a single electrophoretic component that reacts exclusively with antibodies against human foetal myosin and has a mobility and peptide pattern distinct from that of adult fast and slow heavy chains. Foetal myosin is distinguished by the presence of low amounts of a heavy chain immunologically cross-reactive with the adult slow form and of two additional light-chain components: a LC2S light chain and a foetal-specific light chain (LCemb.). The foetal-specific light chain, as shown by one-dimensional-peptide-map analysis, is structurally unrelated to both LC1S and LC1F light chains of human adult myosin. We conclude from these results that the ontogenesis of human muscle myosin shares certain common features with that observed in other species, except for the persistence until birth of a foetal form of heavy chain (HCemb.).

Adult↗
PubMed1982

Polymorphism of myosin light chains. An electrophoretic and immunological study of rabbit skeletal-muscle myosins.

Antibodies specific for rabbit fast-twitch-muscle myosin LCIF light chain were purified by affinity chromatography and characterized by both non-competitive and competitive enzyme-linked immunosorbent assay (ELISA) and a gel-electrophoresis-derived assay (GEDELISA). The antibodies did not cross-react with myosin heavy chains, and were weakly cross-reactive with the LC2F [5,5'-dithio-(2-nitrobenzoic acid)-dissociated] light chain and with all classes of dissociated light chains (LC1Sa, LC1Sb and LC2S), as well as with the whole myosin, from hind-limb slow-twitch muscle. The immunoreactivity of myosins with a truly mixed light-chain pattern (e.g. vastus lateralis and gastrocnemius) correlated with percentage content of fast-twitch-muscle-type light chains. A more extensive immunoreactivity was observed with diaphragm and masseter myosins, which were also characterized, respectively, by a relative or absolute deficiency of LC1Sa light chain. Furthermore, it was found that the LC1Sb light chain of masseter myosin is antigenically different from its slow-twitch-muscle myosin analogue, and is immunologically related to the LC1F light chain. Rabbit masseter muscle from its metabolic and physiological properties and the content, activity and immunological properties of sarcoplasmic-reticulum adenosine triphosphatase, is classified as a red, predominantly fast-twitch, muscle. Therefore our results suggest that the two antigenically different iso-forms of LC1Sb light chain are associated with the myosins of fast-twitch red and slow-twitch red fibres respectively.

Animals↗
PubMed1981

Characterization of human muscle myosins with respect to the light chains.

Isolated myosins from human predominantly fast and slow muscles, human neonatal and foetal muscle were examined for light chain composition by one- and two-dimensional electrophoresis. The LC1F, LC2F and LC3F light chains were identical with their counterparts from rabbit fast myosin. Human LC1S was identified by correlative criteria as a single component having a molecular weight slightly lower than, but an electric charge similar to, that of rabbit LC1Sb. Consequently, human LC1S appears to be much less heterogeneous relative to LC1F than is the case with other mammalian species. A high immunological cross-reactivity was likewise observed, with antibody specific to rabbit LC1F, between the isolated myosins from several human mixed muscles and rabbit fast myosin, though reactivity was highest with foetal myosin (having a pure-fast-light-chain pattern).

Animals↗
PubMed1981

Enzyme-linked immunoassay for study of sarcoplasmic reticulum adenosine triphosphatase.

The immunological reactivity of isolated sarcoplasmic reticulum from rabbit fast muscle was tested with antibody to the Ca2+-pump protein which is the predominant component of these membranes. Microplate enzyme-linked immunoassay (ELISA) gave highly reproducible results under the conventional conditions used for checkerboard titration of soluble antigens and antibody. Parallel electron microscope observation of the incubated SR vesicles, negatively stained with ammonium molybdate, shows that the immunologically reactive form of the Ca2+-pump protein is still present in membrane-bound form.

Adenosine Triphosphatases↗
PubMed1979

Microplate enzyme-linked immunosorbent assay in the study of the structural relationship between myosin light chains.

A microplate enzyme-linked immunosorbent assay (microELISA) for the study of immunochemical relationships between rabbit myosin light chains is described. Purified individual fast-muscle myosin light chains (LC1F, LC2F and LC3F) and their respective antisera, obtained in chicken, were used. Optimal conditions for antigen concentration, antiserum dilution, substrate concentration, incubation time and reproducibility with time were established. The observed cross-reactivities between the different types of light chains associated with rabbit fast-muscle myosin confirm and extend previous results obtained by other authors using radioimmunoassay procedures. It was concluded that microELIAS may be successfully employed also to the study of macromolecule cross-reactivities.

Animals↗