Calcium Ion Concentration in Milk

Abstract

Pulsatile preservation offers the advantage of pretransplant assessment of donor kidneys. Selected electrolyte concentrations of machine perfusate were measured over time in order to: (1) describe electrolyte changes in perfusate during the pulsatile preservation of expanded-criteria donor (ECD) kidneys, and (2) to assess the prog-nostic significance of these characteristics to early graft function. One hundred and fifty ECD kidneys were preserved in our laboratory between 1 January 1995 and 11 Jan-uary 1997. ECD kidneys were defined as those requiring pretrans-plant biopsy. Kidneys were grouped by the presence or absence of delayed graft function (DGF), and perfusion parameters were measured every hour during pulsatile perfusion. All kidneys were preserved by continuous hypothermic pulsatile perfusion using Belzer I1 solution. Renal flow is decreased and renal resistance is increased in the presence of DGF in machine-preserved ECD kidneys. In addition , ionized calcium concentration of the machine perfusate is significantly elevated in the DGF group compared with the No DGF group (0.091 vs 0.054, P = 0.0016). The incidence of DGF is significantly lower in the ECD kidney. Among the pretransplant variables of donor characteristics, perfusion parameters and histology, perfusion parameters are highly predictive of early graft function. In addition, we found that ionized calcium concentration in the perfusate is significantly elevated in kidneys exhibiting DGF, which may have implications for assessing the suitability of donor kidneys for transplantation.

Physicochemical characterization of calcium-supplemented skim milk

“…I). Similar displacements of calcium-inorganic phosphate and calcium-citrate complexes were observed after calcium or magnesium addition to milk [34,37]. These transfers were quantitatively highly dependent on pH.…”

“…To describe the effects of calcium addition to milk, numerous physicochemical studies have been carried out [3,4,7,8,10,11,14,15,21,23,24,26,27,31,34,35,37,39]. These studies principally showed that addition of calcium to milk resulted in a new distribution of ions between milk serum and casein micelles, leading to physicochemical changes in casein micelles.…”

Étude thrombélastographique de la coagulation du lait par la présure: action de la température et de la concentration en calcium

“…Nous avons ensuite examiné ce que devenaient les propriétés mécaniques maxima du coagulum lorsqu'on augmentait la teneur en calcium en prenant du lait cru comme substrat [13], [14], [15].…”

Astringency, a textural defect in dairy products

“…As the astringency in dry milk was primarily attributed to the formation of insoluble calcium-protein aggregates as a result of heat treatment and drying, Josephson (1954) proposed to overcome this defect by sequestering of calcium ion activity and removal of calcium ions from the milk and/or low temperature processing of the dry milk. Tessier and Rose (1958) have also reported that heating skim milk (82°C, 30 min) caused precipitation of calcium phosphate and low-225 ered [Ca2+]; skim milk was also found to contain from 2.5 to 3.4 mmol Ca 2 +/1. Modler and Emmons (1978) have found a way to utilize acid whey obtained from cottage, bakers or cream cheese, which would otherwise be a serious disposai problem.…”