Characterization studies on insoluble total N-nitroso compounds in bacon adipose connective tissue.

Enzymic hydrolysis was employed to solubilize 35% of the total N-nitroso compounds associated with bacon adipose connective tissue. Size exclusion chromatography of the digest showed that 95% of the solubilized N-nitroso compounds had molecular weights equivalent to those of di-, tri- and tetrapeptides. The likely identity of these compounds is discussed in the light of their extractability from acidified solution into ethyl acetate and their thermal and pH stability.

N-Nitrosopyrrolidine formation in bacon.

Evidence is presented that the likely major amine precursors to N-nitrosopyrrolidine in cooked bacon are free proline in the adipose tissue and to a lesser extent, collagenous connective tissues. A model system in which animal lipid is replaced with hydrogenated vegetable oil is described and used in investigating the potential role of prolyl derivatives as precursors to N-nitrosopyrrolidine.

Some nitrosoamino acids in bacon adipose tissue and their contribution to the total N-nitroso compound concentration.

The levels of nitrosoamino acids and apparent total N-nitroso compounds in the adipose tissue of raw bacon have been examined. Nitrosoamino acids were detected in 80% of the samples in levels of up to 0.2 mg/kg. Apparent total N-nitroso compounds were present in all samples in concentrations of between 0.4 and 3.7 mg (N-NO)/kg. Nitrosoamino acids accounted for approximately only 1% of the apparent total N-nitroso compounds. The majority of the apparent total N-nitroso compounds in the adipose tissue were associated with the insoluble connective tissue fraction, with the remainder present as chloroform soluble species.

Synthesis of three N-nitroso dipeptides N-terminal in proline and a method for their determination in food.

The terminal N-nitroso derivatives of L-prolyl-L-alanine, L-prolylglycine and L-prolyl-4-hydroxy-L-proline have been synthesized and characterized. A procedure suitable for their analysis in biological samples has been developed and is based on the preparation of an aqueous extract, extraction into an organic solvent, separation by high-performance liquid chromatography and detection by a chemiluminescence method. The average recovery in all cases was above 69% at the level of 200 micrograms/kg using cured meat as a food matrix; the detection limit was 10 micrograms/kg.

Incidence of some non-volatile N-nitroso compounds in cured meats.

Procedures are described for the use of high-performance liquid chromatography and gas chromatography with a chemiluminescence detector in the analysis of N-nitrosoamino acids, N-nitrosothiazolidine-4-carboxylic acid, N-nitroso-oxazolidine-4-carboxylic acids and N-nitroso dipeptides N-terminal in N-nitrosoproline in cured meat products. The detection limit is around 5-10 micrograms/kg. Evidence is presented for the presence of all these species except the N-nitrosated dipeptides.

Common countertransference issues related to inpatient/residential psychiatric treatment of children.

The contemporary conception of countertransference as potentially useful therapeutically is presented within a Sullivanian -interpersonal framework. A typology of countertransference is outlined with illustrations common within inpatient/residential treatment settings for children. Several clinical vignettes follow which demonstrate the therapeutic application of countertransference. Finally, guidelines are provided for inservice training programs to promote staff understanding and therapeutic management of countertransference in the treatment setting.