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Stepwise, synthetic alteration of oxytocin, guided by conformational and enzymological considerations, has led to analogs with specifically modified activity profiles and resistance to enzymatic inactivation. General requirements for the design of peptides with therapeutic value are discussed.Peptides thus far have not played a major commercial role as therapeutic agents, with certain exceptions such as insulin and adrenocorticotropic hormone (ACTH). However, this situation is rapidly changing as ever more naturally occurring or synthetic low molecular weight peptides with interesting biological activities are being discovered. Additional clinical value can be gained with the development of conceptual approaches for synthetic modification of the molecule in order (i) to endow the analog ideally with only one specific activity (i.e., to change the activity profile of the peptide so that only the desired biological property is expressed, whether agonistic or antagonistic) and (ii) to increase the resistance of the peptide to enzymatic inactivation and to alter tissue distribution, with the hope of prolonging the duration of hormonal actiont. Chemical modifications of the hormonal peptide based on conformational considerations, rather than on an empirical or intuitive approach, should most readily lead to success in obtaining an analog with the required properties.In the case of neurohypophyseal hormones their proposed preferred conformations (2, 3) suggest that substitutions of amino-acid residues in the corners of the 3-turns of the hormones (positions 3, 4, 7, and 8, which are not primarily involved in the intramolecular stabilization of the peptide backbone and, therefore, are available for intermolecular interactions) would lead to analogs with a selectively modified Abbreviation: Asui, 2-aminosuberic acid. * Aspects of this work were presented by R.W. et al. at the Second Amer. Peptide Symposium, Cleveland, Ohio, 1969.

Objective Several studies have shown glycated albumin (GA) BMI, and GA values (r=0.515, p= 0.0004, p=0.010, p=0.036). Stepwise multivariate regression analysis showed that age and ChE values were significant independent variables associated with GA values (β=0.479, R 2 =0.382