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Biomedical subjects

S P Felton

Publications and source records attributed to S P Felton.

11 recordsLinked to original sources
PubMed1997

Ascorbyl-2-sulfate compared with ascorbic acid in Atlantic salmon: uptake and distribution confirmed by mass spectroscopy.

This paper reports an in-depth approach that identifies ascorbyl-2-sulfate (AS) in gastric, blood, liver, and muscle tissues of Atlantic salmon (Salmo salar). To insure the identify of the AS, the study utilized the latest high-performance liquid chromatography (HPLC) technology plus electron ionization mass spectrometry (EIMS). Just before saltwater adaptation stage, juvenile Atlantic salmon were force-fed AS, ascorbic acid (AA), and a molecular-equivalent combination of the two. After tissue analyses for AA and AS were performed by HPLC separation, the HPLC peaks were identified by EIMS. The data collected in this study indicate that Atlantic salmon can absorb AS through the gastric tissue when forced-fed AA and AS as described. The data also indicate that AS is transported through the blood to the liver. There is evidence to indicate that AS is converted to AA in the livers of these salmon. In addition, the muscle tissue contained a large portion of AA and AS.

Animals↗
PubMed1989

Separation of three commercial forms of vitamin C (ascorbic acid, ascorbic-2-sulfate and ascorbate-2-polyphosphate) by HPLC.

A modification of an existing separation technique by this laboratory is described for the separation and quantification of the three commercially available forms of ascorbic acid. The technique has the potential for identifying the various metabolic and degradation products resulting from vitamins C2 and C3 metabolism. A microwave technique is used for tissue heat denaturation and extraction.

Animals↗
PubMed1982

Effects of benzo(a)pyrene on early development of flatfish.

The ontogenetic effects of the environmental carcinogen benzo(a)pyrene (BAP) on three species of larval flatfish were investigated using concentrations (from 0.10 to 4.2 ppb) which were comparable to levels found in polluted harbors. BAP-treated sand sole (Psettichthys melanostichus) eggs displayed a significant decline in hatching success and a significantly higher incidence of developmental anomalies than did control eggs. Flathead sole (Hippoglossoides elassodon) eggs exposed to a single dose of a water-soluble BAP-bovine serum albumin complex demonstrated evidence of toxic injury with pycnotic nuclei present in the integument and, more commonly, in ocular and neural tissues. An increased incidence of morphological anomalies in English sole (Parophyrs vetulus) eggs and larvae exposed to BAP was not detected.

Animals↗
PubMed1981

Uptake of benzo[a]pyrene by gonadal tissue of flatfish (family Pleuronectidae) and its effects on subsequent egg development.

Accumulation of benzo[a]pyrene (BaP) by sexually mature flatfish gonad, its transfer to developing gametes, and its subsequent effects on developing embryos were studied. Thin-layer chromatography revealed both unmetabolized BaP and polar metabolites in the ovary, wolffian ducts, oocytes, and semen of English sole 24 h after ip injection with 200 microCi [3H]BaP. Concentrations of BaP and its metabolites were 3-11 times higher in oocytes and semen than in gonadal tissue. Fertilized eggs from flathead sole that had been fed 4.0 mg BaP 5 h before spawning demonstrated a significantly lower (p less than 0.001) hatching success (11.9%) than eggs from control fish (56.6%). Morphological abnormalities were found in only 1.6% of control embryos but in 5.6% of embryos from treated females.

Animals↗
PubMed1979

Circadian rhythm in the elderly: a study using a cortisol-specific radio-immuno-assay.

Plasma cortisol levels and diurnal variation have been examined in 30 elderly patients and compared with a control group of 29 middle-aged healthy subjects. The elderly patients had normal plasma cortisol levels which exhibited the diurnal variation seen in the younger age group. In spite of microscopic degenerative changes in the adrenals with age their secretory function and response to hypothalamic pituitary stimulation appear to remain normal.

Age Factors↗