In vitro evaluation of antiviral and virucidal activity of a high molecular weight hyaluronic acid

Summary1. Infusions of low molecular weight dextran (Mw = 42 000) to dogs in doses of 1—1.5 g per kg body weight did not produce any significant changes in the coagulation mechanism.2. Infusions of high molecular weight dextran (Mw = 1 000 000) to dogs in doses of 1—1.5 g per kg body weight produced severe defects in the coagulation mechanism, namely prolongation of bleeding time and coagulation time, thrombocytopenia, pathological prothrombin consumption, decrease of fibrinogen, prothrombin and factor VII, factor V and AHG.3. Heparin treatment of the dogs was found to prevent the decrease of fibrinogen, prothrombin and factor VII, and factor V otherwise occurring after injection of high molecular weight dextran. Thrombocytopenia was not prevented.4. In in vitro experiments an interaction between fibrinogen and dextran of high and low molecular weight was found to take place in systems comprising pure fibrinogen. No such interaction occurred in the presence of plasma.5. It is concluded that the coagulation defects induced by infusions of high molecular weight dextran are due to intravascular coagulation.

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Preparation and Characterization of the High Molecular Weight [3H]Hyaluronic Acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922151 ◽

1992 ◽

Vol 57 (10) ◽

pp. 2151-2156 ◽

Cited By ~ 2

Author(s):

Peter Chabreček ◽

Ladislav Šoltés ◽

Hynek Hradec ◽

Jiří Filip ◽

Eduard Orviský

Keyword(s):

Molecular Weight ◽

Hyaluronic Acid ◽

High Molecular Weight ◽

Methyl Bromide ◽

High Performance ◽

Hydrogen Atoms ◽

Isolation And Characterization ◽

Labelling Procedure ◽

Enzymatic Depolymerization

Two methods for the preparation of high molecular weight [3H]hyaluronic acid were investigated. In the first one, hydrogen atoms in the molecule were replaced by tritium. This isotopic substitution was performed in aqueous solution using Pd/CaCO3 as the catalyst. In the second method, the high molecular weight hyaluronic acid was alkylated with [3H]methyl bromide in liquid ammonia at a temperature of -33.5 °C. High-performance gel permeation chromatographic separation method was used for the isolation and characterization of the high molecular weight [3H]hyaluronic acid. Molecular weight parameters for the labelled biopolymers were Mw = 128 kDa, Mw/Mn = 1.88 (first method) and Mw = 268 kDa, Mw/Mn = 1.55 (second method). The high molecular weight [3H]hyaluronic acid having Mw = 268 kDa was degraded further by specific hyaluronidase. Products of the enzymatic depolymerization were observed to be identical for both, labelled and cold biopolymer. This finding indicates that the described labelling procedure using [3H]methyl bromide does not induce any major structural rearrangements in the molecule.

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High molecular weight form of hyaluronic acid reduces neuroinflammatory response in injured sciatic nerve via the intracellular domain of CD44

Journal of Biomedical Materials Research Part B Applied Biomaterials ◽

10.1002/jbm.b.34731 ◽

2020 ◽

Vol 109 (5) ◽

pp. 673-680

Author(s):

I‐Ming Jou ◽

Tung‐Tai Wu ◽

Che‐Chia Hsu ◽

Cheng‐Chang Yang ◽

Jhy‐Shrian Huang ◽

...

Keyword(s):

Molecular Weight ◽

Hyaluronic Acid ◽

Sciatic Nerve ◽

High Molecular Weight ◽

Intracellular Domain ◽

Neuroinflammatory Response ◽

High Molecular Weight Form ◽

Molecular Weight Form

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Physicochemical and Antifungal Properties of Clotrimazole in Combination with High-Molecular Weight Chitosan as a Multifunctional Excipient

Marine Drugs ◽

10.3390/md18120591 ◽

2020 ◽

Vol 18 (12) ◽

pp. 591

Author(s):

Bożena Grimling ◽

Bożena Karolewicz ◽

Urszula Nawrot ◽

Katarzyna Włodarczyk ◽

Agata Górniak

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Weight Ratio ◽

Scanning Calorimetry ◽

Minimal Inhibitory Concentrations ◽

Dissolution Tests ◽

Effective Combination ◽

The Impact ◽

High Molecular Weight Chitosan

Chitosans represent a group of multifunctional drug excipients. Here, we aimed to estimate the impact of high-molecular weight chitosan on the physicochemical properties of clotrimazole–chitosan solid mixtures (CL–CH), prepared by grinding and kneading methods. We characterised these formulas by infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffractometry, and performed in vitro clotrimazole dissolution tests. Additionally, we examined the antifungal activity of clotrimazole–chitosan mixtures against clinical Candida isolates under neutral and acid conditions. The synergistic effect of clotrimazole and chitosan S combinations was observed in tests carried out at pH 4 on Candida glabrata strains. The inhibition of C. glabrata growth reached at least 90%, regardless of the drug/excipient weight ratio, and even at half of the minimal inhibitory concentrations of clotrimazole. Our results demonstrate that clotrimazole and high-molecular weight chitosan could be an effective combination in a topical antifungal formulation, as chitosan acts synergistically with clotrimazole against non-albicans candida strains.

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