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Biomedical subjects

J L Bada

Publications and source records attributed to J L Bada.

10 recordsLinked to original sources
PubMed1978

Aspartic acid racemization in heavy molecular weight crystallins and water insoluble protein from normal human lenses and cataracts.

High D/L aspartic acid ratios are observed in heavy molecular weight aggregates and in water-insoluble protein extracted from whole lenses and nuclear and cortical regions. Purified alpha-, beta-, and gamma-crystallins have low D/L ratios. Fractionation of urea-solubilized material from the water-insoluble protein yields four molecular weight classes of proteins. Fractions representing crosslinked material or apparently degraded products have high D/L ratios. Racemization within lens proteins may contribute to formation of the water-insoluble fraction seen in aging lenses and cataracts.

Adolescent↗
PubMed1977

Seroepidemiology of the poliovirus in Monrovia (Liberia).

Neutralizing antibodies against poliovirus have been studied in 265 persons in Monrovia (Liberia). 34% of the individuals studied possessed antibodies against the three polioviruses, 23% against two, 26% against one; the remaining 17% showed none. The three poliovirus antibodies were evenly distributed amongst the population, although there was an indication that antibodies to polio 2 occurred more commonly in females than in males. The distribution of the antibodies did not seem to be influenced by place of residence, source of drinking water or social class. Significant variations in the immunological state according to age were noted. The study of concordance and discordance of antibody titre in the blood of neonates and their mothers revealed that the lower percentage of titre concordance for polio 3 has no statistical value. The low titre in the neonates (an average for each poliovirus scarcely above 1:16) is a sign of insufficient titre in the adults. The need for a massive antipoliomyelitis campaign among infants and adult women is stressed.

Age Factors↗
PubMed1977

Considerations on the role of aspartic acid racemization in the aging process.

Racemization of aspartyl residues in human dentine and enamel proteins has been shown to occur at a rate which corresponds to an enrichment in the D-aspartic acid content of 0.1% per year. This rate can be used to calculate the ages of living people or the in vivo lifetimes of slowly turned over proteins. We present stereochemical arguments for conformational changes in proteins as a consequence of racemized amino acid residues. In metabolically stable proteins, this phenomenon may play some part in the aging process. In renewed proteins, where certain factors may accelerate racemization, conformational changes induced by racemization could regulate protein degradation.

Adolescent↗