Mannitol VOLUME

Glycerol has been widely employed for this purpose but mannitol and sorbitol are more effective, and have the advantage that being solids they do not materially increase the volume of the solution being titrated 0.5-0.7 g of mannitol or sorbitol in 10 mL of solution is a convenient quantity. 

Procedure. To determine the purity of a sample of boric acid, weigh accurately about 0.8 g of the acid, transfer quantitatively to a 250 mL graduated flask and make up to the mark. Pipette 25 mL of the solution into a 250 mL conical flask, add an equal volume of distilled water, 2.5-3 g of mannitol or sorbitol, and titrate with standard 0.1 M sodium hydroxide solution using phenolphthalein as indicator. It is advisable to check whether any blank correction must be made dissolve a similar weight of mannitol (sorbitol) in 50 mL of distilled water, add phenolphthalein, and ascertain how much sodium hydroxide solution must be added to produce the characteristic end point colour. 

Specific Volume of Gases Formed on Explosion. 723ml/g (NG 712ml) (Ref 46) Stabilization. Chromatographically pure Mannitol Hexanitrate was mixed with varying percentages of 22 stabilizers and the mixts tested for stability in the 100° heat test best results were obtained with a mixt of 96% MHN, 2% Amm oxalate, and 2% dicyandiamide (4.07% wt loss after 48 hours, 5.74% after 96 hours) (Ref 56). The use of ethylene oxide as a stabilizer is reported in Ref 27 Thermal Decomposition. Slow heating causes decompn at 150° with evolution of red fumes (Ref 20, p 249)... 

Fig. 9. Transfer of mannitol bound to inside-out vesicles to the cytoplasmic volume. (A) Unphos-phorylated ll ". (B) Phosphorylated 11 . It is assumed that the phosphoryl group transfer from the enzyme to the sugar can only take place when the sugar is bound the cytoplasmic-facing binding site, E-Pcyt Mtl (see also Fig. 6).

Therapeutic measures that have been used to decrease the incidence of contrast-induced nephropathy include extracellular volume expansion, minimization of the amount of contrast administered, and treatment with oral acetylcysteine. Theophylline, fenoldopam, loop diuretics, mannitol, dopamine, and calcium antagonists have no effect or may worsen ARF. 

Figure 5 Temperature profile in primary drying of dobutamine HCl-mannitol (1 1), 53 mg solids/mL, 10 mL fill volume. Vials are 5304 molded glass vials (8.3 cm2 cross-sectional area) which are placed in a flat aluminum tray. The heat flux is 42 cal/(cm2 hr), and the chamber pressure is 0.1 torr. (From Ref. 5.)...

The mother liquor was then treated with a small amount of ether, whereupon it separated into two layers. The lower layer consisted of a black sirup, which, when treated with absolute alcohol very slowly deposited some crystals, 1 g., consisting largely of D,L-mannitol. The upper layer was treated with a large volume of ether, which caused the precipitation of a considerable quantity of a brown sirup. Crystallization began almost immediately, especially when the sirup was treated with absolute alcohol. The crystals were collected and there was obtained in this way 12 g. of crude allitol. After solution in water and precipitation with alcohol, the crystals melted at 140°, but still contained a small amount of impurity. After several recrystallizations they melted at 149°. 

The answer is c (HardmanT pp 695-697.) Mannitol increases serum osmolarity and therefore pulls water out of cells, cerebrospinal fluid (C5F), and aqueous humor. This effect can be useful in the treatment of elevated intraocular or intracranial pressure. However, by expanding the intravascular volume, mannitol can exacerbate CHF... 

The answer is b. (Hardman, pp 695-697.) A significant increase in the amount of any osmotically active solute in voided urine is usually accompanied by an increase in urine volume Osmotic diuretics affect diuresis through this principle. The osmotic diuretics (such as mannitol) are nonelectrolytes that are freely filtered at the glomerulus, undergo limited re absorption by the renal tubules, retain water in the renal tubule, and promote an osmotic diuresis, generally without significant Na excretion. Ln addition, these diuretics resist alteration by metabolic processes. 

TMA measurements have been helpful in explaining the breakage of vials during the warming of frozen solutions of mannitol and other stereoisomers [1.125]. For example, above -25 °C mannitol expands 30 times more than standard type 1 flint glass. Depending on the filling volume and the concentration, 10-40 % of the vials break when filled with 3 % mannitol solution. 

To date, only a few solution calculations for carbohydrates have been attempted (one such study of mannitol and sorbitol is described in the chapter by Grigera in this volume), but the results of these early studies bear out the expectation that solvation effects in carbohydrate systems can be both significant and difficult to predict. In the case of pyranoid rings, molecular solvation is further complicated by the close juxtaposition of these groups in essentially fixed relative orientations (assuming no conformational changes in the ring). Under such circumstances, molecular stereochemistry could play important physical roles, as is... 

Forced diuresis is occasionally useful. It may cause volume overload or electrolyte disturbances. Forced diuresis is useful for phenobarbital, bromides, lithium, salicylate, or amphetamines overdoses. Do not use for tricyclic antidepressants, sedative-hypnotics, or highly protein-bound medications. The most common agents employed are furosemide and osmotic diuretics with mannitol. 

Find the outlet concentration of cells from the reactor when 1 m /hr of mannitol solution (C o = 6 gm/m ) is fed directly to a mixed flow reactor of volume... 

Mannitol (OsmitroL others) [Osmotic Diuretic] Uses Cerebral edema, T lOP/ICP, renal impair, poisonings Action Osmotic diuretic Dose Test dose 0.2 g/kg/dose IV over 3-5 min if no diuresis w/in 2 h, D/C Oliguria 50-100 g IV over 90 min T lOP 0.5-2 g/kg IV over 30 min Cerebral edema 0.25-1.5 g/kg/dose IV >30 min Caution [C, ] w/ CHF or volume overload Contra Anuria, dehydration, HE, PE Disp Inj SE May exacerbate CHF, N/V/D Interactions t Effects OF cardiac glycosides X effects OF barbiturates, imipramine, Li, salicylates EMS Monitor ECG for hypo-/hyperkalemia (T wave changes) OD May cause dehydration, t urine frequency/amount hypotension and CV collapse symptomatic and supportive... 

The use of urea (Ureaphil, Ur evert) has declined in recent years owing both to its disagreeable taste and to the increasing use of mannitol for the same purposes. When used to reduce cerebrospinal fluid pressure, urea is generally given by intravenous drip. Because of its potential to expand the extracellular fluid volume, urea is contraindicated in patients with severe impairment of renal, hepatic, or cardiac function or active intracranial bleeding. 

Osmotic diuretics are used to increase water excretion in preference to sodium excretion. This effect can be useful when avid Na + retention limits the response to conventional agents. It can be used to maintain urine volume and to prevent anuria that might otherwise result from presentation of large pigment loads to the kidney (eg, from hemolysis or rhabdomyolysis). Some oliguric patients do not respond to osmotic diuretics. Therefore, a test dose of mannitol (12.5 g intravenously) should be given before starting... 

Osmotic diuretics alter Starling forces so that water leaves cells and reduces intracellular volume. This effect is used to reduce intracranial pressure in neurologic conditions and to reduce intraocular pressure before ophthalmologic procedures. A dose of 1-2 g/kg mannitol is administered intravenously. Intracranial pressure, which must be monitored, should fall in 60-90 minutes. 

Mannitol is rapidly distributed in the extracellular compartment and extracts water from cells. Prior to the diuresis, this leads to expansion of the extracellular volume and hyponatremia. This effect can complicate heart failure and may produce florid pulmonary edema. Headache, nausea, and vomiting are commonly observed in patients treated with osmotic diuretics. 

Mannitol Physical osmotic effect on tissue water distribution because it is retained in the vascular compartment Marked increase in urine flow, reduced brain volume, decreased intraocular pressure, initial hyponatremia, then hypernatremia Renal failure due to increased solute load (rhabdomyolysis, chemotherapy), increased intracranial pressure, glaucoma IV administration Toxicity Nausea, vomiting, headache... 

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