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Biomedical subjects

Mark L Failla

Publications and source records attributed to Mark L Failla.

5 recordsLinked to original sources
PubMed2003

Trace elements and host defense: recent advances and continuing challenges.

Although it is widely recognized that essential trace elements are required for the differentiation, activation and performance of numerous functions of immune cells, the specific roles of these inorganic micronutrients in these processes remain largely undefined. New insights about the participation of zinc, iron and copper in the selection, maturation and early activation events of the immune cells have been gained by judicious use of available tools in analytical cell biology, molecular genetics and array technology. Also, randomly controlled clinical and community trials demonstrate that zinc supplementation can enhance immunocompetence and decrease the incidence and severity of some infections in individuals with diagnosed or suspected mild zinc deficiency. These exciting results provide an impetus to evaluate the potential benefits of supplementation programs for individuals and groups with suboptimal trace element status as a cost-effective means of reducing the risk of infectious diseases.

Communicable Disease Control↗
PubMed2003

Safety assessment of recombinant green fluorescent protein orally administered to weaned rats.

Several proposed biotechnological applications of green fluorescent protein (GFP) are likely to result in its introduction into the food supply of domestic animals and humans. We fed pure GFP and diets containing transgenic canola expressing GFP to young male rats for 26 d to evaluate the potential toxicity and allergenicity of GFP. Animals (n = 8 per group) were fed either AIN-93G (control), control diet plus 1.0 mg of purified GFP daily, modified control diet with 200 g/kg canola (Brassica rapa cv Westar), or control diet with 200 g/kg transgenic canola containing one of two levels of GFP. Ingestion of GFP did not affect growth, food intake, relative weight of intestine or other organs, or activities of hepatic enzymes in serum. Comparison of the amino acid sequence of GFP to known food allergens revealed that the greatest number of consecutive amino acid matches between GFP and any food allergen was four, suggesting the absence of common allergen epitopes. Moreover, GFP was rapidly degraded during simulated gastric digestion. These data indicate that GFP is a low allergenicity risk and provide preliminary indications that GFP is not likely to represent a health risk.

Administration, Oral↗
PubMed2002

Sodium copper chlorophyllin: in vitro digestive stability and accumulation by Caco-2 human intestinal cells.

Sodium copper chlorophyllin (SCC), a mixture of water-soluble chlorophyll derivatives, is used as both a food colorant and a common dietary supplement. Although the potential antimutagenic and antioxidant properties of this commercial preparation have been demonstrated, limited information is available on its digestion and absorption by humans. Stability of SCC was examined during simulated gastric and small intestinal digestion. Three preparations were subjected to in vitro digestion: SCC in water, SCC in water + 10% corn oil, and SCC in applesauce. SCC components from raw material preparations and in digested samples were analyzed by C(18) HPLC with photodiode array detection. Cu(II)chlorin e(4), the major chlorin component of SCC, was relatively stable during simulated digestion. In contrast, greater than 90% of Cu(II)chlorin e(6) was degraded to undetermined products during digestion. Recovery of Cu(II)chlorin e(6) after digestion was increased by incorporation of SCC into applesauce, suggesting a protective role of the inclusion matrix for stabilization of labile SCC components. Accumulation of SCC derivatives was investigated by using differentiated cultures of the TC7 clone of the Caco-2 human intestinal cell line. Cellular accumulation from media containing 0.5 to 60 ppm SCC was linear with intracellular content ranging between 0.2 and 29.6 microg of total SCC per mg of cellular protein. Uptake of SCC by Caco-2 cells was significantly (p < 0.01) lower in cultures incubated at 4 degrees C than in those incubated at 37 degrees C. Although intracellular SCC was transported into both apical and basolateral compartments when Caco-2 cells were grown on inserts, apical efflux was significantly greater (p < 0.01) than basolateral efflux. Stability of Cu(II)chlorin e(4) during in vitro digestion and effective uptake by Caco-2 enterocyte-like cells support the likelihood that a portion of this SCC component or its metabolites is absorbed from the human intestine.

Caco-2 Cells↗