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The effect of alpha 2-macroglobulin, one of the major antiproteinases in the plasma of vertebrates, on the action of the aspartic proteinases chymosin, cathepsin D and cathepsin E towards peptide and protein substrates at pH 6.2 was examined. Activities towards protein substrates were blocked, thus demonstrating that alpha 2-macroglobulin can inhibit aspartic proteinases, in addition to serine proteinases, cysteine proteinases and metalloproteinases.

An ad hoc committee of the North American Primary Care Research Group (NAPCRG) was appointed to develop a classification system for procedures in primary care. The committee developed and field tested a completely hierarchical four digit process code for primary care. It is hoped that with wide-spread use and further testing, the code will become a nucleus for an international companion volume to ICHPPC-2 (International Classification of Health Problems in Primary care, second edition). This first version is being made available to interested potential users at this time.

Cathepsin D was affinity-purified on pepstatin-Sepharose from control rat liver, from Yoshida ascites hepatoma (AH-130) cells, and from the liver of AH-130 tumour-bearing rats. Apparent molecular mass and immunological reactivity, as determined by SDS-PAGE and immunoblotting, were identical for the three enzyme preparations. The active enzyme concentrations were determined by active-site titration. Catalytic parameters were measured for the three enzymes using two synthetic chromogenic peptides as substrates, and inhibition constants were determined for the proteinases with a number of naturally-occurring as well as synthetic inhibitors. All three enzymes were clearly distinguished from cathepsin E, since none of them was affected by the protein inhibitor from Ascaris lumbricoides. The cathepsin D isolated from AH-130 cells was indistinguishable in its kinetic properties from rat liver cathepsin D, except in its susceptibility to inhibition by isovaleryl-pepstatin. On isoelectrofocusing, the isoenzyme pattern of the tumour enzyme was shifted somewhat towards more basic pI values by comparison with rat liver cathepsin D. These findings are considered with respect to the possibility of an alteration in the S4 subsite of the enzyme active site cleft.

Three aspartic proteinases with similar Mr values (approx. 80,000) but from distinct sources (human gastric mucosa, human erythrocyte membranes and rat spleen) were shown to have immunological cross-reactivity and comparable mobilities when subjected to polyacrylamide-gel electrophoresis under non-denaturing conditions. Kinetic parameters (kcat, Km and Ki) were determined for the interactions of the three enzymes with two synthetic chromogenic substrates and five inhibitors (naturally occurring and synthetic). On this basis it would appear that all of the enzymes should be considered equivalent to cathepsin E. pH-activity measurements indicated that the aspartic proteinase that originated from the erythrocyte membranes retained activity at a higher pH value than either of its readily soluble counterparts.

The concept of the self has been used in several attempts to resolve the epistemological problems of what is subjective and what is objective, what is personal and what is organismic. In addition, it has been used to mediate between the hermeneutic and natural-science approaches to psychoanalytic explanation, between the motivational and causal dimensions of our theory and experience. In the case of Kohut, the self was initially invoked to deal with clinical difficulties associated with the analysis of patients with narcissistic personality disorders more recently, it has become the central article in a "self psychology" that addresses presumed deficiencies in the traditional psychoanalytic picture of psychopathology. But the concept of the self is not suited to be a panacea for resolving theoretical or clinical difficulties. The self as person refers to an entity that is both enduring and changing; it describes continuity in the face of change and change in the face of continuity. Abend (1974) comes closest to capturing this attribute of the self in his image of the tidal beach with a configuration that changes but an essence that remains the same. Eisnitz (1980) evokes something similar in his figure-ground conception of the self-representation. The crux of the matter is that the notion of self-experience includes a variety of phenomena that cannot be contained within a single self-construct--be it normal pathologic, grandiose, or otherwise. As a result of these considerations, I have argued against the use of the self as a superordinate concept in psychoanalytic theory and have focused on the shortcomings of three self psychologies that use the self in this way. I believe that Klein, Gedo, and Kohut all offer the self as a kind of conceptual tranquilizer for the philosophical, theoretical, and clinical dualities that are inherent in psychoanalytic work. Grossman addressed himself to these dualities as far back as 1967 and elaborated on the problems with Simon (1969) in a pathbreaking paper on anthropomorphism in psychoanalysis. Grossman and Simon contended that the controversy about anthropomorphism in psychoanalytic theory pertains to the basic confusion in psychology between meaning and causality. They submitted that until this confusion was dispelled and until some superordinate concept was found that could "encompass both kinds of discourse", attempts to transform psychoanalysis into a general psychology would result in failure.(ABSTRACT TRUNCATED AT 400 WORDS)

Kinetic constants were determined for the interaction of the HIV-2 aspartic proteinase with a synthetic substrate and a number of inhibitors at several pH values. Acetyl-pepstatin was more effective towards HIV-2 proteinase than the renin inhibitor, H-261; this effect is exactly the opposite from that observed previously for the proteinase from the HIV-1 AIDS virus.