Library

Notes: Erythrocyte 2,3-diphosphoglycerate (2,3-DPG) and associated haematological parameters were measured throughout the normal menstrual cycle, in each trimester of pregnancy and on the third day post partum. There was no significant change during the menstrual cycle but the 2,3-DPG concentration was increased early in pregnancy, and thereafter gradually decreased. Although other metabolic changes are likely to contribute to the increase in 2,3-DPG concentration, it is concluded that ‘functional anaemia’, secondary to increased oxygen demand, is a more important stimulus than the decrease in haemoglobin concentration. The implications of a decreased oxygen affinity of haemoglobin, secondary to the rise in 2,3-DPG concentration, are discussed in relation to anaemia and blood transfusion in pregnancy.

Notes: An investigation correlating protein analyses of cervical mucus with sperm penetration tests and an assessment of consistency is presented. When the protein content was below 1·5 μg. per mg. of wet mucus and only albumin was present, sperm penetrability was optimal. When the protein content was greater than 12·5 μg. per mg. of wet mucus and transferrin and immunoglobulin were present in addition to albumin, sperm penetration was severely restricted. Protein analyses are proposed as a useful method of assessing cervical mucus function with particular reference to the effect of progestogens on the genital tract.

Notes: Patients considered to be at extra risk of fetal loss because of previous history were assessed throughout pregnancy for hormone deficiency by cervical mucus smears, vaginal cytology and total oestrogen excretion. There was a significantly higher incidence of light-for-dates babies when cervical mucus ferning was noted early in pregnancy and persisted or recurred after 16 weeks. Early detection of‘placental insufficiency’by ferning in the mucus would allow closer study of the factors which impair intrauterine growth.

Notes: SUMMARY. Twenty-four patients with resistant patches of eczema and 6 patients with resistant patches of psoriasis have been treated with beta rays using a Strontium 90 source. The results are discussed and compared with those obtained with other similar methods of treatment. It is concluded that in carefully selected patients with benign dermatoses beta ray therapy from a Strontium 90 source is safe and effective.

Notes: Summary.— The natural history of mycosis fungoides (MF) in 21 patients is noted and discussed with particular reference to the response to therapy with superficial x-rays (16 patients) and beta rays from a Strontium 90 source (5 patients).Useful palliation, which is not related to the duration of the disease, is obtained with either treatment but the convenience and safety of Strontium 90 make this form of treatment preferable to superficial x-rays.It is suggested that beta ray therapy from a Strontium 90 source is the treatment of choice for MF presenting as excessive pruritus, widespread erythema and lichenification, exfoliation or as palmar and plantar byperkeratosis.

Notes: This paper begins with a brief review of radiation theory as applied to water temperature determinations. Errors introduced in “radiant” temperature measurements due to nonblackness of the water surface and the effects of the atmosphere are included in this discussion.The airborne scanner system is described. Analysis and display of scanner data using the Laboratory for Applications of Remote Sensing (LARS) display system are discussed.Thermal maps of four sections of the Wabash River are included and points of interest of each map are discussed in the text.

Notes: Summary It is shown that the Gouy-Chapman double layer analysis adequately describes the variation of the surface potential of monolayers of acidic natural lipids over a wide range of surface charge density and salt concentration. It is also shown that the potential which initially appears when an electrolyte gradient is rapidly imposed across a bilayer membrane is due to a difference in the double layer potentials on the two sides of the membrane. This conclusion follows from the fact that the observed bilayer potentials arise much more rapidly than can be accounted for by charge migration across the membrane and from the observation that the bilayer membrane concentration potentials, when measured immediately after establishment of a gradient, are equal to the surface potential change observed when the subphase concentration of a monolayer of the same lipid is changed by an amount equal to the gradient across the bilayer. The bilayer potential and monolayer potential changes, so measured, agree in a number of different electrolyte solutions over a wide range of electrolyte concentrations and surface charge densities. Because of this agreement and the applicability of the Gouy theory to monolayers, initial bilayer potentials may be calculated if the composition of the mixture used to form the membrane is known, provided that the pK's and areas of such components are available. In the absence of this information, membrane potentials may be calculated from electrophoretic data on the membrane lipid mixture; the conditions under which the latter approach is possible have been determined. The experimental results indicate that the composition of monolyers and bilayers spread from the same lipid mixture in decane are very similar, that the composition of the two types of film closely resembles the composition of the solution used to generate them, and that bilayer membranes are close-packed. The evidence further indicates that if any hydrocarbon solvent remains in these bilayers, it must be so situated that it contributes little, if anything, to the surface area. The steady state potential in the bilayer membrane system is frequently not identical with the initial potential which supports the hypothesis that in many cases only a fraction of the electrical conductance of unmodified membranes is caused by the ions which constitute the bulk electrolyte. An expression for the relationship between diffusion and double layer potentials has been derived which shows that, in the absence of any intrinsic selectivity of the hydrocarbon region of the membrane for hydrogen, hydroxyl, or impurity, the two potentials should be identical.