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The characteristics and proportions of human lymphocyte populations capable of lysing IgG coated target cells were studied. Monolayer of target erythrocytes coated with rabbit IgG were employed to detect and isolate the lytic effector lymphocytes. Normal peripheral blood effector lymphocytes were shown to express IgG receptors, and a total of four cell types possesing different surface markers were identified. An average of 68% (range 51-80%) of the effector lymphocytes had T lymphocytes antigen and were capable of SRBC rosette formation, and 32% of the lymphocytes lacked T lymphocyte markers. Two populations of these T lymphocytes were identified: one possesses SRBC and IgG receptors, and the other possesses SRBC, IgG and complement receptors. The proportion of the former was estimated as 53.2% and the latter as 14.8% of the total effector cell population. Two other cell types were distinguished among the non-T lymphocytes. One type of lymphocytes bear IgG receptors (21.6%) and the other has both IgG and complement receptors (10.4%). The cytolytic capacity of the two T lymphocyte subpopulations is suggested to be an important reaction of the immune reactive T lymphocytes during the immune response.

ABSTRACT A simple, two-parameter methodology has been developed, by which the kinetic unstability of a macroemulsion i.e., sedimentation or creaming, can be separated from the aggregative unstability. It is applicable to systems in which, after cessation of agitation, a clear phase develops, by coalescence of droplets that have been formed under agitation, The methodology has been applied to a series of two-phase systems in which the upper phase was organic and the lower phase, a brine-external mlcroemulsion. The coalescence time parameter, ϕ, was found to be a simple function of the interfacial tension, in the composition range studied, for which γ varied from 0.024 to 0.33 dyne/cm. The sedimentation time parameter, τ was interpreted in terms of a Stokes’ law drift process together with a previously-established relation between drop size and intensity of agitation. The predicted form of the relation between the experimental variables was confirmed.

The contact angle of CH2I2, α-bromonaphthalene and aniline on crosslinked polystyrene has been measured. The polymer was swollen for as long as 60 days in the liquid whose contact angle was to be measured. The surface free energy, γs, of unswelled polystyrene was estimated from the contact angles and the swelling results, using an equation which had previously been proposed by Good. The value of γs is estimated to be 42±2 ergs/cm2.

Surface tension measurement data are described that allow the determination of and the distinction between the long-range Lifshitz-van der Waals (LW) and the short-range (SR) forces that together constitute “hydrophobic interactions”. A novel explicit formulation of the partial contributions of hydrogen bonds to surface tension and to free energy of adhesion is introduced. The different rules that apply to LW and to SR interactions are elaborated upon and the equations needed for the quantitative expression of these two interactions are given. The results obtained by this approach for energies of adhesion are compared with values derived from association and dissociation energies that have been determined earlier, showing an excellent agreement between these two different approaches. A number of applications of our surface-thermodynamic approach (treating LW and SR interactions separately) to various separation processes are discussed with regard to various modes of liquid chromatography, adsorpt...

A single step method to isolate human T lymphocytes was achieved using a rosette technique to deplete non-T lymphocytes. Erythrocytes coated simultaneously with IgG and complement were used to form rosettes with cells bearing such receptors during a short incubation period and the rosetting cells removed by gradient centrifugation. T lymphocytes were isolated (greater than 96% T cells) without exposing to much experimental manipulations and in good recovery (mean 60%, range 40-75%).

A technique is described for performing temperature scanning measurements of the surface tension of polymer solutions. Measurements on solutions of a high molecular weight and a low molecular weight monodisperse polystyrene in tetralin, decalin, and n-hexadecane are reported. Whereas previous investigations of other physical properties of polystyrene solutions had revealed only one anomaly, at about 50°C in some cases and at about 70–80°C in others, the curves presented here show two anomalies, near 45°C and 70, respectively. These anomalies are tentatively attributed to conformational changes of the polymer chains.

Interstitial 125I was successfully used in the retreatment of a large recurrent malignant schwannoma in the retroperitoneum. After an average tumor dose of 160 Gy the tumor calcified and the patient is well, without disease 2 years later.