Starch hydroxyethyl

Binders. Paper-coating biaders are either polymers derived from aatural sources or syathetic polymers. The largest volume, aaturally derived biader is starch (qv) (99). Starch is provided ia derivatized form or unmodified form pead com starch is used predomiaanfly for the latter. Unmodified starch is solubilized by thermal conversion or enzyme conversion. The most common derivatized products are acetylated [9045-28-7] oxidized, and hydroxyethylated starches. 

Low DS hydroxyethyl starches are used as paper coatings and sizes to improve sheet strength and stiffness. They are also employed as paper-coating color adhesives, and to increase fiber bonding in paper products. Hydroxyethylstarches are also used as textile warp sizes. 

Hydroxyethyl starch 5g%(50g/1) Impermeant colloid, suppresses cell swelling... 

Colloids. The overall incidence of reactions has been estimated to less than 0.22%. Gelatins and dextrans are more frequently incriminated than albumin or hetastarch. Evidence for IgE-mediated adverse reactions to gelatin has been reported. Adverse reactions to dextrans were estimated to 0.275%, when it was 0.099% for albumin and 0.058% for hydroxyethyl starch solutions, and 0.03% for gelatin solutions [22, 23]. 

Schwarz S, Schwab S, Bertram M, Aschoff A, Hacke W. Effects of hypertonic saline hydroxyethyl starch solution and mannitol in patients with increased intracranial pressure after stroke. Stroke 1998 29(8) 1550-1555. 

Use a crystalloid (normal saline or lactated Ringer s solution) or a colloid (hydroxyethyl starch or albumin 5%) intravenous boluses... 

Generally, the major adverse effects associated with colloids are fluid overload, dilutional coagulopathy, and anaphy-lactoid/anaphylactic reactions.24,32 Although derived from pooled human plasma, there is no risk of disease transmission from commercially available albumin or PPF products since they are heated and sterilized by ultrafiltration prior to distribution.24 Because of direct effects on the coagulation system with the hydroxyethyl starch and dextran products, they should be used cautiously in hemorrhagic shock patients. This is another reason why crystalloids maybe preferred in hemorrhagic shock. Furthermore, hetastarch can result in an increase in amylase not associated with pancreatitis. As such, the adverse-effect profiles of the various fluid types should also be considered when selecting a resuscitation fluid. 

The choice and combinations of different size components must take account of many factors if optimum results are to be obtained. Much has been published regarding the optimisation of size formulations in relation to desizing processes [177-183]. Cotton warp yarns sized with starch are normally woven at high humidity (80% and above) to keep yarn breakages low, as the starch film is brittle at low humidity. It has been shown [183], however, that improved weavability at moderate relative humidity (e.g. 65%) can be obtained using (a) starch/acrylamide or hydroxyethyl starch at not less than 15% add-on or (b) poly(vinyl alcohol), which gave excellent results even at a low add-on of 5-6%. 

Addition of acrylamide to starch improved the performance of cotton yarn more than acrylamide alone, but addition of poly(vinyl alcohol) to starch lowered the performance of the yarn compared with poly(vinyl alcohol) alone. Overall, taking into account economic considerations, stringent pollution requirements and the needs of desizing, the singlecomponent hydroxyethyl starch showed optimum acceptability for weaving performance at moderate relative humidity. 

As in the case of other cardiovascular diseases, the possibility of antioxidant treatment of diabetes mellitus has been studied in both animal models and diabetic patients. The treatment of streptozotocin-induced diabetic rats with a-lipoic acid reduced superoxide production by aorta and superoxide and peroxynitrite formation by arterioles providing circulation to the region of the sciatic nerve, suppressed lipid peroxidation in serum, and improved lens glutathione level [131]. In contrast, hydroxyethyl starch desferrioxamine had no effect on the markers of oxidative stress in diabetic rats. Lipoic acid also suppressed hyperglycemia and mitochondrial superoxide generation in hearts of glucose-treated rats [132],... 

Takaori M, Fukui A. Treatment of massive hemorrhage with liposome encapsulated human hemoglobin (NRC) and hydroxyethyl starch (HES) in beagles. Art Cells Blood Substit Immobil Biotechnol 1996 24 643. 

The dominant specialty starch used in size press applications is the hydroxyalkyl derivative commonly made wjth ethylene oxide to yield a hydroxyethyl starch. Low substituted hydroxypropy1 starch has similar properties. These starches were introduced to the industry in 1950 and they have grown in importance each year. Recent expansions in production by major producers has indicated their continuing dominance of the specialty starch surface sizing and coating field. 

Three colloids are currently employed as plasma volume expanders— the two polysaccharides, dextran and hydroxyethyl starch, as well as the polypeptide, gelatin. 

Hydroxyethyl starch (hetastarch) is produced from starch. By virtue of its hydroxyethyl groups, it is metabolized more slowly and retained significantly longer in blood than would be the case with infused starch. Hydroxyethyl starch resembles dextrans in terms of its pharmacological properties and therapeutic applications. 

Hydromorphone Hydroxocobalamin Hydroxychloroquine Hydroxyethyl starch Hydroxyprogesterone caproate Hyoscyamine sulfate... 

Heins, D., Kulicke, W. -M., Kauper, P, Thielking, H. (1998). Characterization of acetyl starch by means ofNMR spectroscopy and SEC/MALLS in composition with hydroxyethyl starch. Starch, 50,431 37. 

Hydroxyethyl starch (HES) is a derivative of the highly branched starch, amylopectin, in which the anhydroglucose residues are substituted by hydroxyethyl groups to reduce metabolic degradation by plasma a-amylase. The... 

Figure 20.1 Basic structure of hydroxyethyl starch (HES), showing HES (-CH2-CH2-OH) substitution at positions C2and C6.

Rehm M, Orth V, Scheingraber S, Kreimeier U, Brechtelsbauer H, Finsterer U. Acid-base changes caused by 5% albumin versus 6% hydroxyethyl starch solution in patients undergoing acute normovolemic hemodilution a randomized prospective study. Anesthesiology 2000 93(5) 1174-83. 

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