The physiology of lactoferrin.

This paper reviews our current knowledge of the structure and function of the iron-binding protein lactoferrin. In particular, it attempts to relate the various proposed physiological functions of lactoferrin to its most characteristic biochemical properties, i.e. its ability to bind iron and its highly basic nature. The extent to which various physiological functions can be considered as definitely established is critically reviewed, and suggestions for future research are proposed.     

The Saline Lakes of Saskatchewan III. Chemical Characterization

The salinity of Saskatchewan saline lakes varies up to 342%₀. Highly saline lakes are widely distributed. Some reach saturation at high summer temperatures but salt precipitation occurs on cooling. Saline lakes tend to increase in salinity with time but the greatest changes occur in the shallow more saline lakes. The lakes are dominated by sodium, magnesium and sulphate. The cation sequences are dominated by sodium or magnesium while calcium and potassium are proportionally much smaller. Chloride or bicarbonate-carbonate are secondary to sulphate among the anions. Ion sequences tend to be characteristic of certain physiographic regions. Lake types were magnesium (sodium) sulphate, sodium sulphate and sodium (magnesium) sulphate in order of abundance of lakes. Phosphorus and ammonia were high in concentration but nitrate and silica were scarce. The lakes were all alkaline between pH 7.8 and 9.8. The evolution of closed saline lakes is briefly discussed.     

The Saline Lakes of Saskatchewan II. Locale,Hydrography and other Physical Aspects

The geology and physiography, climate, soils and vegetation of the saline lakes region of southern Saskatchewan are briefly reviewed. The location and morphometry of 60 saline lakes was determined. Some of them are large (307 km²) but mean depths do not exceed 10 m and many are very shallow. Light penetration varied considerably from very turbid shallow lakes to Redberry Lake where the 1% light level was below 16.5 m. Light extinction coefficients for the entire water column of deeper lakes (7) varied from 0.256 to 2.558. Shallow lakes failed to stratify thermally but a dozen deeper lakes stratified for at least several months. Higher salinity tends to prolong stratification. Thermal stratification augmented chemical stratification in two meromictic lakes. Maximum temperature up to 30 °C in very saline shallow waters was recorded while temperatures as low as-3 °C occurred under the ice. Freezing was delayed and thawing accelerated in more saline lakes. Annual heat budgets varied from 3350 to 13,900 g cal cm-² in seven lakes. Oxygen concentration was reduced below thermoclines and was virtually absent below the ice in very shallow lakes and, at times, in a very productive lake.