Combined Aldehyde-Fuchsin and Periodic Acid-Schiff Staining of the Pituitary

Aldehyde-fuchsin and the periodic acid-Schiff procedure can be applied in sequence to the same tissue section and combined with a stain for acidophils, such as orange G, for routine analysis of the pituitary. This is made possible by fixation in a mixture containing 5% chrome-alum, 5% HgCl₂ and 5% formalin; control of the pH and the activity of the aldehyde-fuchsin; and increased sensitivity of the Schiff reagent, effected by reducing its SO₂ content. Although designed especially for the pituitary, the procedure is also applicable to other histological problems.     

Clostridium perfringens in Meat and Meat Products

A total of 262 specimens of meat and meat dishes were examined for the presence of Clostridium perfringens. Of this total, 161 were raw, unprocessed beef, veal, lamb, pork, or chicken; 101 were processed meats and meat dishes. C. perfringens was isolated from 113 (43.1%) of these specimens. The highest percentage of contamination (82%) was found in veal cuts, and the lowest (4.7%) in sliced sandwich meats and spreads. Only 2 of the 113 isolates were shown to produce heat-resistant spores, which indicates a very low incidence (0.8%) of contamination. These findings indicate that outbreaks of C. perfringens food-borne disease in the Cincinnati area are caused principally by the contamination of the food with vegetative cells or spores of the organism after cooking. Studies of the effects of various holding temperatures on the growth of C. perfringens indicated that, in the range of 5 to 15 C, no multiplication would occur, but that viable cells would still be present at the end of a 5-day holding period. Extremely rapid growth occurred at temperatures around 45 C, and complete inhibition of growth was accomplished between 49 and 52 C.