Dextran

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Dextran is a complex branched glucan (polysaccharide made up of many glucose molecules) composed of chains of varying length (from 3 to 2000 kilodaltons).

The straight chain consists of -1.6 glycosidic links between glucose molecules, whereas branches range from -1.3 relationships. This distinctive branching distinguishes dextran from dextrin, which is a straight-chain glucose polymer moored by -1.4 or -1.6 connections.

Dextran was first invented by Louis Pasteur as a microbial product in wine, but mass production was only possible after the development by Allene Jeanes of a process using bacteria. Dextran is now synthesized from sucrose by certain lactic acid bacteria, most notably being Leuconostoc mesenteroides and Streptococcus mutans . Dental plaque rich dextrans.

Medicinally used as antithrombotic (antiplatelet), to reduce blood viscosity, and as a volume expander in hypovolemia. Dextran 70 is on the WHO Essential Medicines List of the most important drugs needed in the health system.

Video Dextran

Usage

Micro Surgery

These medications are commonly used by micro surgeons to reduce vascular thrombosis. The antithrombotic effects of dextran are mediated through the binding of erythrocytes, platelets, and vascular endothelium, increasing their electronegativity and thereby reducing erythrocyte aggregation and platelet stickiness. Dextrans also reduces factor factor VIII-Ag Von Willebrand, thereby decreasing platelet function. The clots formed after administration of dextran are more easily lysed because of altered thrombus structures (platelets are distributed more evenly with coarse fibrin). By inhibiting? -2 antiplasmin, dextran serves as a plasminogen activator, so it has a thrombolytic feature.

Outside of these features, the larger dextran, which is not out of the vessels, is a strong osmotic agent, so it has been used immediately to treat hypovolemia. Hemodilution caused by volume expansion with dextran use improves blood flow, thus further improving the patency of microanastomosis and reducing thrombosis. However, no differences were detected in antitrombotic effectiveness compared with intra-arterial and intravenous dextran.

Dextrans available in various molecular weights ranging from 3,000 Da to 2,000,000 Da. Larger transplants (& gt; 60,000 Da) are excreted poorly from the kidneys, so stay in the blood for weeks until they are metabolized. As a result, they have prolonged antithrombotic and colloidal effects. In this family, dextran-40 (MW: 40,000 Da), has become the most popular member for anticoagulation therapy. Nearly 70% of dextran-40 is excreted in urine within the first 24 hours after intravenous infusion, while the remaining 30% is maintained for several more days.

Other medical uses

Used in a few drops as a lubricant. and in certain intravenous fluids to dissolve other factors, such as iron (in a solution known as Iron Dextran).
An intravenous solution with dextran function both as volume expansion and parenteral nutrition means. Such a solution provides an osmotic neutral fluid that once in the body is digested by cells into glucose and free water. This is sometimes used to replace blood lost in emergency situations, when replacement blood is not available, but should be used with caution because it does not provide the necessary electrolytes and may cause hyponatremia or other electrolyte disturbances.
It also increases blood sugar levels.

Laboratory using

Dextran is used in osmotic voltage techniques to apply osmotic pressure to biological molecules.
This is also used in the size exclusion chromatography matrix; an example is Sephadex.
Dextran has also been used in beads to aid in bioreactor applications.
The dextran has been used in immobilization in the biosensor.
Dextran in particular binds to the early endosome; Fluorescent-labeled dextran can be used to visualize this endosome under a fluorescent microscope.
The dextran can be used as a stabilizer coating to protect metal nanoparticles from oxidation and increase biocompatibility.
Dextrose coupled with fluorescent molecules such as fluorescein isothiocyanate can be used to create a difusible molecular concentration gradient for imaging and to allow characterization of later gradient slopes.
Fluorescan-labeled dextran solutions can be refined through engineered vessels to analyze vascular permeability
Dextran is used to make microcarriers for industrial cell culture

Maps Dextran

Side effects

Although relatively few side effects are associated with dextran use, these side effects can be very serious. These include anaphylaxis, excessive volume, pulmonary edema, cerebral edema, or platelet dysfunction.

A rare but significant complication of the dextran osmotic effect is acute renal failure. The pathogenesis of renal failure is the subject of much debate with direct toxic effects on tubules and glomeruli compared with intraluminal hyperviscosity which are some of the proposed mechanisms. Patients with a history of diabetes mellitus, renal insufficiency, or vascular disorders are most at risk. Brooks and others recommend the avoidance of dextran therapy in patients with chronic renal insufficiency.