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M J Palmieri

Publications and source records attributed to M J Palmieri.

22 records · Page 2Linked to original sources

Single radial immunodiffusion method for screening Staphylococcal isolates for enterotoxin.

A direct system for screening large numbers of staphylococcal isolates for enterotoxin production has been developed. The system employs polyvalent (serotypes A, B, C, D, and E) immunodiffusion assay slides in conjunction with a multiple-culturing system for toxin production. With the combined system, as many as 50 cultures can be screened simultaneously on a single assay slide having a sensitivity of about 0.3 microgram/ml. The system should be useful for detecting potential enterotoxin in foods containing a predominance of non-enterotoxigenic strains.

Enterotoxins↗

Relationship of thyroid status and serum N-acetyl-beta-glucosaminidase isoenzyme activities in humans.

Serum from 28 hyperthyroid, hypothyroid, and euthyroid pre- or early puberty females was examined for N-acetyl-beta-glucosaminidase (HEX) activity. Total, isoenzyme A (labile), and isoenzyme B (stable) levels were determined for this enzyme. A high degree of correlation (r = 0.76; p less than 0.001) exists between total hexosaminidase activity and thyroid hormone levels (as reflected by the Free Thyroxine Index). Examining each isoenzyme individually, A is selectively enhanced (r = 0.84; p less than 0.0005) whereas B displays no significant change regardless of thyroid activity. In hyperthyroid individuals, levels of total hexosaminidase (730 +/- 67 units) (mean +/- S.D.) and isoenzyme A (516 +/- 46) were significantly higher than levels found in either the hypothyroid (total: 547 +/- 30; isoenzyme A: 352 +/- 31) or euthyroid (total: 620 +/- 81; isoenzyme A: 423 +/- 45) groups. However, no change was observed in levels of isoenzyme B among hypothyroid (195 +/- 19), euthyroid (197 +/- 43) and hyperthyroid (215 +/- 32) groups. These data substantiate our earlier findings in the rat, wherein thyroxine administration evoked a similar response in the liver. They are of particular interest in light of the deficiency of HEX A in variants of GM2 gangliosidosis.

Acetylglucosaminidase↗

Effects of proteins and polynucleotides on the activity of various hydrolases.

The effect of various macromolecules on the activity of several hydrolases was studied. Dilution of partially purified acid beta-galactosidase from ileal mucosa of suckling rats resulted in a decrease of specific activity. The relationship between specific activity and dilution of the enzyme suggests a dissociation of the enzyme. This could be prevented by addition of several proteins tested. However, addition of DNA to the assay mixture for acid beta-galactosidase caused an inhibition. This inhibition could be prevented by addition of proteins. Other polynucleotides and tRNA also exert an inhibitory effect that is prevented by albumin, but nucleotides have no effect. This inhibition occurs maximally at a low pH (3.0-4.0); no inhibition is observed at pH5.5. A similar pH-dependent inhibition by DNA was also found with various other acid hydrolases.

Animals↗