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SUMMARY. Differential scanning calorimetry (DSC) was used to study thermal transitions of the following whey proteins and enzymes in milk ultrafiltrate solution: /Mactoglobulin, a-lactalbumin, serum albumin, y-globulin, apo-and Fe-lactoferrin, lysozyme, ribonuclease, a-chymotrypsin and xanthine oxidase. Denaturation enthalpies (A-Ho), denaturation temperatures (T D ) and the half width of the denaturation peaks in DSC thermograms (A? 1 !)) were determined and the degree of renaturation was estimated by rescanning previously denatured samples. A fair correlation between the results obtained by DSC and other more classical methods was found in general. However, for some proteins (a-lactalbumin, lysozyme, ribonuclease and xanthine oxidase), which have so far been considered relatively thermostable, calorimetry reveals conformational changes starting at temperatures as low as about 45 °C. In these cases thermostability observed after heat treatment of milk should be interpreted in terms of renaturation and not of high temperatures of denaturation.Calorimetric techniques have been found useful for studying the effect of heat on proteins in aqueous solutions (Privalov, 1974; Sturtevant, 1974). The published calorimetric investigations of protein denaturation, however, either do not include milk proteins or were not carried out in solutions resembling the natural milk medium. It was thus considered useful to examine the thermal transitions of milk proteins in milk ultrafiltrate by differential scanning calorimetry (DSC). This should give some insight into the structure and stability of proteins in milk as well as the changes in the properties of milk and milk products during heat treatment.The present communication summarizes the results of a calorimetric investigation of the heat-induced transitions and reactions observed in milk ultrafiltrate of the following proteins: /

Objective To evaluate the safety and efficacy of thermal balloon therapy for menorrhagia.Design Prospective, observational study. Setting Fifteen centres in Canada and Europe.Population Two hundred and ninety-six eligible women for whom follow up data were available for three months or more. Eligible women included those for whom further fertility was not a concern, were not postmenopausal, suffered from intractable menorrhagia, had a normal uterine cavity, and who were fully informed regarding the investigational nature of uterine thermal balloon therapy.Methods Three hundred and twenty-one procedures of balloon endometrial ablation were performed using the same protocol between June 1994 and August 1996. Exclusion criteria included structural uterine abnormality or (pre) malignant lesions. Treatment entailed controlled heating of fluid in an intrauterine balloon. General anaesthesia was employed in the 61% of procedures while local anaesthesia with or without sedation was used in 39% of cases.Analysis Follow up data at 3 and/or 6, and/or 12 months were required for inclusion in the analysis. A paired t test, Wilcoxon signed-ranks test, and multiple and logistic regression analyses were used to evaluate the changes in bleeding and dysmenorrhoea patterns, and possible confounding variables, respectively. Success was defined as the subjective reduction of menses to eumenorrhoea or less.Results No intra-operative complications occurred, and post-operative morbidity was minimal. Success of the procedure was constant over the year (range 88%-91%). Treatment led to a significant decrease in the duration of menstrual flow and severity of pain (P < 0.0001). Increasing age, higher balloon pressure, smaller uterine cavity, and a lesser degree of pre-procedure menorrhagia were associated with significantly improved results. Pre-treatment with gonadotrophin releasing hormone agonists increased amenorrhoea and spotting rates (P = 0-03), but was only used in 5% of cases.Conclusion Thermal balloon endometrial ablation appears to be safe, as well as effective in properly selected women with menorrhagia and is potentially an outpatient procedure.

Aqueous solutions of sorbitol derived from biosustainable resources are converted by catalytic hydrogenolysis to a mixture of C 4 -C 6 polyols for the synthesis of alkyds † employed in paint manufacture. Copper catalysts were selected because of their larger activity in the dehydroxylation reaction than in C-C bond breakage. Reactions at 180 °C under H 2 -pressure in the presence of CuO-ZnO catalyst gave a 73% yield of C 4+ polyols, and more specifically, 63% of deoxyhexitols. The mixture of polyols was effectively employed as a substitute for hydrocarbon-derived polyols in the synthesis of alkyd polymers.