New strategy for the design of ligands for the purification of pharmaceutical proteins by affinity chromatography

A new approach for the identification of ligands for the purification of pharmaceutical proteins by affinity chromatography is described. The technique involves four steps. Selection of an appropriate site on the target protein, design of a complementary ligand compatible with the three-dimensional structure of the site, construction of a limited solid-phase combinatorial library of near-neighbour ligands and solution synthesis of the hit ligand, immobilisation, optimisation and application of the adsorbent for the purification of the target protein. This strategy is exemplified by the purification of a recombinant human insulin precursor (MI3) from a crude fermentation broth of Saccharomyces cerevisiae.

Compound grating discrimination in extrafoveal and amblyopic vision

Compound grating discrimination was measured in normal foveal and extrafoveal vision as well as in central vision of amblyopic subjects. Two types of discrimination were examined: 0 degrees versus 180 degrees and 90 degrees versus 270 degrees phase shift of the second harmonic relative to the fundamental. In common with several previous studies, we found that both 0/180 and 90/270 discriminations are possible in extrafoveal vision. However, we show that differences in foveal and extrafoveal sensitivity can be eliminated for both types of discrimination by scaling the stimulus size appropriately. The extent of spatial magnification necessary to equate foveal and extrafoveal performance differed markedly, with 90/270 discriminations requiring much more magnification. In the amblyopic subjects, the magnitude of the 90/270 deficit was greater than the 0/180 deficit in all six amblyopes tested. In common with previous investigations, we suggest that the visual system adopts a discrimination strategy, based upon differences in local features, between the patterns to be discriminated. One process registers positional relationships, while a second process registers local contrast differences. In this context, the reduced ability of the normal periphery and amblyopic fovea to perform mirror-symmetric discriminations is explained in terms of losses in positional acuity.

Pharmacotherapeutics of positive inotropes

Pharmacology is integrated in all areas of nursing practice. From the most basic entry level to the most advanced clinical practice, nursing curriculums are not complete without pharmacology. The word "pharmacology" often makes nurses and other health care professionals feel uneasy. Pharmacology implies complicated words and formulas that seem foreign, recalled only from one's most distant recollections of college years. For many health care providers, courses in pharmacology are taken before they care for patients, leaving them with little practical experience from which to relate. Education involves not simply learning and doing, but also applying knowledge. A basic understanding of pharmacology is needed to break down the barriers of pharmacologic communication and put the clinician at ease with terminology so often used by the medical community.