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Tritiated thymidine (3HT) was used in one of three ways to label deoxyribonucleic acid replication in epidermal cells of miniature swine: (1) the radioactive material was injected intracutaneously in vivo; (2) the radioactive material was injected intracutaneously into biopsy specimens and the specimens incubated in vitro in Eagle's medium, or (3) uninjected biopsy specimens were incubated in Eagle's medium with added 3HT. The first two methods yielded the same proportions of labeled cells with uniform distribution of labeled cells. The third method resulted in labeling of cells mainly at the periphery of the biopsy specimens. The advantages of the in vitro over the in vivo technique of injection of 3HT includes the fact that injecting a biopsy specimen avoids the problems of large amounts of radioactive waste disposal in animal studies or the legal and ethical problems of tracer studies in humans.

An adequate biopsy that includes the subcutaneous tissue is very helpful in the evaluation of patients with suspected connective tissue disease. However, the histologic features must often be correlated with the clinical features and other laboratory tests for a definitive diagnosis. An objective histologic diagnosis can usually be made in scleroderma, lupus erythematosus panniculitis, amyloidosis, and angioedema, and in diseases such as lepromatous leprosy and mycosis fungoids (which are sometimes confused with connective tissue diseases). Correlation with clinical features and, sometimes, other laboratory tests is often required to establish a diagnosis of scleredema, dermatomyositis, myxedema, and lichen myxedematosus. The features in cheilitis granulomatosa usually are not specific, but a biopsy is helpful to rule out other diseases.

A group of 220 patients with mycosis fungoides (MF) and other lymphomatous diseases was treated with sustained topical applications of dilute aqueous solutions of mechlorethamine hydrochloride for intervals ranging in excess of seven years. Response to treatment, immunologic responsiveness, and subsequent course and survival were inversely related to magnitude of disease at time of starting treatment. Relapses were common and in most instances were related to failure to maintenance of topical therapy rather than to drug resistance. In selected patients topical therapy with an analog of mechlorethamine (nor-mechlorethamine) and with topical immunogenic agents provided additional improvement.

The large change in the electronic absorption spectrum of cytidine on going from an aqueous to an aprotic medium is attributed to the existence of a hydrogen bonded solvent-solute complex in solvents capable of donating a proton. The spectrum of cytidine in a variety of solvents and the spectra of a number of nontautomerising model compounds are presented. The tautomerisin of cytidine and its biological implications are discussed.

Working within the restrictions of a model, we have calculated the circular dichroism of the dinucleoside phosphates ApA, CpC, and CpA for various conformations. Comparing the calculated curves with those measured in aqueous solution we find agreement for (1) ApA as a right-handed helix with both bases either as in B-form DNA, or else rotated 180° around the glycosidic bond, (2) CpC as the right-handed conformation with both bases as in DNA, (3) ApC as either the right-handed conformation with both bases as in DNA, or else as a left-handed helix with both bases rotated 180°, and (4) CpA as either a left-handed helix with both bases in a left-handed DNA, or else in the right-handed conformation with both bases rotated 180°. In addition, we have investigated circular dichroism as a measure of unstacking. We find that opening the bases to a 90° total angle (base planes perpendicular) reduces the intensity of the calculated bands to 20% of their original value. Further, we find that allowing the sliding of one base past the other does not lead to a temperature dependence consistent with experiment.

Physiological resistance is an important component of integrated strategies used to control white mold [caused by Sclerotinia sclerotiorum (Lib.) de Bary] a major disease of common bean (Phaseolus volgaris L.) in North America. Information pertaining to inheritance of physiological resistance, as detected by the greenhouse straw test, and its relationship with field resistance is lacking. The objectives of this study were to compare physiological resistance as detected by two separate straw tests with field resistance, evaluate heritability of physiological resistance, and to characterize the disease reaction of G 122 by quantitative trait locus (QTL) analysis. This was done in a recombioant inbred population (A 55/G 122) consisting of 67 F derived lines. The greenhouse tests with five and six replications, respectively, and the field test with three replications were conducted in randomized complete block designs. Moderate heritability for disease reaction (scored from 1 = no symptoms to 9 = severe disease) was observed across the straw tests (0.65) and in the field (0.78). Inheritance of disease reaction was further investigated with a framework linkage map composed of 74 markers, Interval mapping detected a QTL on linkage group B7 near the phaseolin seed protein (Phs) locus that explained 38% of the phenotypic variation for disease score across the straw tests. The same B7 QTL (26%), and an additional QTL (18%) on B1 near the fin gene for determinate growth habit conditioned field resistance. A QTL (34%) for canopy porosity, a measure of potential disease avoidance, also mapped to the fin locus. Results confirmed that physiological resistance as detected by the straw lest was an integral component of field resistance, and that both physiological and avoidance mechanisms contributed to field resistance in the A 55/G 122 population. The landrace G 122 clearly provides breeders with a heritable source of physiological resistance to combat white mold discase.

The circular dichroism of Eco RI restriction endonuclease was measured to 178 nm and analyzed for secondary structure. The results (33% alpha-helix, 25% beta-sheet, 17% turns, and 25% other structures) compare well with our joint prediction from sequence data.

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Auger spectroscopy was employed to study platinum surfaces anodized either in with evolution of oxygen, or in with evolution of chlorine. For the Pt anodized in , Pt and oxygen interact to form a stable film of stoichiometry. Anodization in resulted in a less stable film; although relatively large concentrations of oxygen and chlorine are present after anodization, these are removed by electron beam bombardment in the Auger apparatus.