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Biomedical subjects

S L Allen

Publications and source records attributed to S L Allen.

100 records · Page 6Linked to original sources
PubMed1971

Metabolism of Common Substrates by the Reiter Strain of Treponema pallidum.

The utilization of glucose, amino acids, fatty acids, bicarbonate, purines, and pyrimidines by the Reiter treponeme was studied by using carbon 14-labeled substrates. The distribution of carbon from the substrates into various cell components was determined. Radioactivity from labeled bicarbonate in the cellular protein was restricted to aspartic acid. The Reiter treponeme is capable of synthesizing glycine, serine, alanine, aspartic acid, glutamic acid, proline, and possibly ornithine. Phenylalanine, arginine, lysine, leucine, isoleucine, valine, threonine, and histidine do not appear to be synthesized by this treponeme. The Reiter treponeme cannot synthesize fatty acids, and thymine is not incorporated. Glucose is a major carbon and energy source. Arginine, histidine, serine, threonine, and glutamic acid are degraded by the Reiter treponeme and may serve as energy sources. It was calculated that exogenously supplied amino acids contribute 41 to 54% of the cellular material; fatty acids, 18%; and glucose, 28 to 43%.

Journal Article↗
PubMed1967

Genomic exclusion: a rapid means for inducing homozygous diploid lines in Tetrahymena pyriformis, syngen 1.

Genomic exclusion is an abnormal form of conjugation occurring between cells with defective micronuclei and normal cells with diploid micronuclei. The progeny are heterocaryons; each cell has an old macronucleus but a new diploid micronucleus derived from one meiotic product of the normal mate. Such cells express genes found in the old macronucleus, are sexually mature, and can be specifically selected. When inbred, they give rise to lines genetically homozygous at all known loci.

Genes↗
PubMedDate not supplied

Effect of IDPN on the expression of POMC-derived peptides in rat motoneurones.

Immunocytochemistry was used to detect beta-endorphin and alpha-melanotropin (alpha-MSH) in lumbar spinal motoneurones in rats treated with beta,beta'-iminodiproprionitrile (IDPN), a neurotoxicant that targets motoneurones or corn oil, which has no known neurotoxicity. After IDPN treatment most of the motoneurones were immunoreactive for both peptides but after corn oil treatment immunostaining was negligible. It is suggested that increased expression of the POMC-derived peptides may be part of the regenerative repertoire of the damaged motoneurone regardless of the cause of the lesion. Alternatively the peptides may simply accumulate in the motoneurones as a result of impaired axoplasmic transport.

Animals↗
PubMedDate not supplied

Primary multicystic undifferentiated embryonal sarcoma of the liver in an adult presenting with peripheral eosinophilia.

Primary undifferentiated embryonal sarcoma of liver is an extremely rare pathologic entity in the adult population. An unusual case is reported of a 44-year-old female who presented with multiple hepatic cysts and peripheral eosinophilia, initially thought to be hydatid disease of the liver. Angiogram revealed neovascularization. Surgical biopsy showed an anaplastic mesenchymal neoplasm. Pathologic findings are presented and the relevant literature reviewed. Hepatic undifferentiated embryonal sarcoma should be included in the differential diagnosis of eosinophilia accompanying hepatic cysts.

Adult↗