scholarly journals Modification of Collagen/Gelatin/Hydroxyethyl Cellulose-Based Materials by Addition of Herbal Extract-Loaded Microspheres Made from Gellan Gum and Xanthan Gum

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3507
Author(s):  
Justyna Kozlowska ◽  
Weronika Prus-Walendziak ◽  
Natalia Stachowiak ◽  
Anna Bajek ◽  
Lukasz Kazmierski ◽  
...  
Keyword(s):  
Xanthan Gum ◽  
Polymeric Materials ◽  
Gellan Gum ◽  
Porous Polymer ◽  
Polymer Materials ◽  
Herbal Extract ◽  
Hydroxyethyl Cellulose ◽  
In Vitro Tests ◽  
Swelling Properties

Because consumers are nowadays focused on their health and appearance, natural ingredients and their novel delivery systems are one of the most developing fields of pharmacy, medicine, and cosmetics. The main goal of this study was to design, prepare, and characterize composite materials obtained by incorporation of microspheres into the porous polymer materials consisting of collagen, gelatin, and hydroxyethyl cellulose. Microspheres, based on gellan gum and xanthan gum with encapsulated Calendula officinalis flower extract, were produced by two methods: extrusion and emulsification. The release profile of the extract from both types of microspheres was compared. Then, obtained microparticles were incorporated into polymeric materials with a porous structure. This modification had an influence on porosity, density, swelling properties, mechanical properties, and stability of materials. Besides, in vitro tests were performed using mouse fibroblasts. Cell viability was assessed with the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The obtained materials, especially with microspheres prepared by emulsion method, can be potentially helpful when designing cosmetic forms because they were made from safely for skin ingredients used in this industry and the herbal extract was successfully encapsulated into microparticles.

scholarly journals Anti-Inflammatory Properties of Injectable Betamethasone-Loaded Tyramine-Modified Gellan Gum/Silk Fibroin Hydrogels

Biomolecules ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1456
Author(s):  
Isabel Matos Oliveira ◽  
Cristiana Gonçalves ◽  
Myeong Eun Shin ◽  
Sumi Lee ◽  
Rui Luis Reis ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Mechanical Properties ◽  
Silk Fibroin ◽  
Therapeutic Efficacy ◽  
Composite Structures ◽  
Gelation Time ◽  
Polymeric Materials ◽  
Gellan Gum ◽  
Traditional Use

Rheumatoid arthritis is a rheumatic disease for which a healing treatment does not presently exist. Silk fibroin has been extensively studied for use in drug delivery systems due to its uniqueness, versatility and strong clinical track record in medicine. However, in general, natural polymeric materials are not mechanically stable enough, and have high rates of biodegradation. Thus, synthetic materials such as gellan gum can be used to produce composite structures with biological signals to promote tissue-specific interactions while providing the desired mechanical properties. In this work, we aimed to produce hydrogels of tyramine-modified gellan gum with silk fibroin (Ty–GG/SF) via horseradish peroxidase (HRP), with encapsulated betamethasone, to improve the biocompatibility and mechanical properties, and further increase therapeutic efficacy to treat rheumatoid arthritis (RA). The Ty–GG/SF hydrogels presented a β-sheet secondary structure, with gelation time around 2–5 min, good resistance to enzymatic degradation, a suitable injectability profile, viscoelastic capacity with a significant solid component and a betamethasone-controlled release profile over time. In vitro studies showed that Ty–GG/SF hydrogels did not produce a deleterious effect on cellular metabolic activity, morphology or proliferation. Furthermore, Ty–GG/SF hydrogels with encapsulated betamethasone revealed greater therapeutic efficacy than the drug applied alone. Therefore, this strategy can provide an improvement in therapeutic efficacy when compared to the traditional use of drugs for the treatment of rheumatoid arthritis.

scholarly journals Analysis of Void Growth and Coalescence in Porous Polymer Materials. Coalescence in Polymer Materials

2013 ◽  
Vol 3 (3) ◽  
pp. 452-460
Author(s):  
S. A. Reffas ◽  
M. Elmeguenni ◽  
M. Benguediab
Keyword(s):  
Volumetric Strain ◽  
Polymeric Materials ◽  
Porous Polymer ◽  
Polymer Materials ◽  
Geometrical Shape ◽  
Engineering Applications ◽  
Initial Size ◽  
Advanced Stages ◽  
New Methodologies ◽  
Void Growth And Coalescence

The use of polymeric materials in engineering applications is growing more and more all over the world. This issue requests new methodologies of analysis in order to assess the material’s capability to withstand complex loads. The use of polyacetal in engineering applications has increased rapidly in the last decade. In order to evaluate the behavior, the damage and coalescence of this type of polymer, a numerical method based on damage which occurs following several stages (nucleation of cavities, their growth and coalescence in more advanced stages of deformation) is proposed in this work. A particular attention is given on the stress-strain and the volumetric strain evolution under different triaxiality and for three initial void shapes. Its application to polyacetal allows approving this approach for technical polymers. Finally, this method allow us to compare the obtained results of basic calculations at different triaxiality and to discuss their possible influence on the initial size and the geometrical shape of the porosity on the material failure.

Testing of Polymer Materials: What Methods Should be Used?

1991 ◽  
Vol 19 (2) ◽  
pp. 222-225
Author(s):  
Per Kjellstrand ◽  
Ulf Boberg
Keyword(s):  
Renal Replacement Therapy ◽  
Replacement Therapy ◽  
Toxicity Testing ◽  
Test Battery ◽  
Polymer Materials ◽  
In Vitro Tests ◽  
Paraffin Oil ◽  
Low Sensitivity ◽  
Animal Tests

Tests, performed over a ten-year period, on 653 polymers intended for use in extracorporeal renal replacement therapy, were evaluated. The test battery used included animal tests, in vitro tests and chemical tests. Some tests were found to have a very low sensitivity. Thus, acute systemic toxicity testing in mice with sodium chloride, ethanol or paraffin oil as extractants was performed on a total of 806 occasions. Only two of these resulted in a “fail” decision. The final outcome of the tests for the majority of materials could be predicted by the results of the UV absorption, chloride, inhibition of cell growth, and tin tests. Of the materials that passed these four tests, less than 2% were not approved on the basis of the whole test battery. The experiments show that only a limited number of tests have to be performed when testing polymers intended for use in extracorporeal renal replacement therapy.

The Application of Atomic Force Microscopy to the Characterization of Industrial Polymer Materials

MRS Bulletin ◽  
2004 ◽  
Vol 29 (7) ◽  
pp. 464-470 ◽  
Author(s):  
Georg K. Bar ◽  
Gregory F. Meyers
Keyword(s):  
Atomic Force Microscopy ◽  
Polymeric Materials ◽  
Porous Polymer ◽  
Polymer Materials ◽  
Phase Imaging ◽  
Structure Property ◽  
Polymer Systems ◽  
Force Microscopy ◽  
Atomic Force

AbstractAtomic force microscopy (AFM) is now well established among the tools of choice for the analysis and characterization of materials.Applications of AFM span many industries including chemicals, plastics, pharmaceuticals, and semiconductors.Advancements in AFM instrumentation over the last five years have expanded the range of application of this technology to investigate thermal and mechanical properties of complex materials at high spatial resolution as well as structural and morphological characterization of materials subjected to thermal and mechanical stresses.In particular, this has been an enabling technology for an improved understanding of structure–property relationships in polymeric materials including homopolymers, blends, impact-modified polymer systems, porous polymer systems, and semicrystalline polymers.Practical examples illustrate applications of contact, tapping-mode, phase-imaging, hot-stage, and scanning thermal methods for the characterization of modern industrial polymer materials.

scholarly journals Evaluation of Gellan Gum Film Containing Virgin Coconut Oil for Transparent Dressing Materials

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Nur Arifah Ismail ◽  
Siti Fatimah Mohamad ◽  
Maizatul Akma Ibrahim ◽  
Khairul Anuar Mat Amin
Keyword(s):  
Bacterial Resistance ◽  
Composite Films ◽  
Coconut Oil ◽  
Gellan Gum ◽  
Material Surface ◽  
Human Skin Fibroblast ◽  
Virgin Coconut Oil ◽  
Swelling Properties ◽  
Dressing Materials

We examined the potential of virgin coconut oil (VCO) incorporated in gellan gum (GG) films as a dressing material. Pure GG film is extremely brittle and inclusion of 0.3% (w/w) VCO in the GG film (GG-VCO3) improved the toughness (T≈0.67±0.33 J g−1) of the composite films. Swelling properties and water vapor transmission rates of GG-VCO composite films decreased, whereas thermal behavior values increased upon the addition of higher concentrations of VCO. Cell studies exhibit that the VCO is noncytotoxic to human skin fibroblast cells (CRL2522) with limited cell growth observed on GG-VCO3 films at 1,650 cells/well after incubation for 72 h which could be due to hydrophobic influence of the material surface. The qualitative and in vitro quantitative antibacterial results revealed that VCO does not possess strong bacterial resistance against all four tested bacteria, that is, two Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and two Gram-negative bacteria (Pseudomonas aeruginosa and Proteus mirabilis).

Anti-Diabetic Activity of a Mineraloid Isolate, in vitro and in Genetically Diabetic Mice

2011 ◽  
Vol 81 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Joel Deneau ◽  
Taufeeq Ahmed ◽  
Roger Blotsky ◽  
Krzysztof Bojanowski
Keyword(s):  
Dna Microarrays ◽  
Human Fibroblasts ◽  
Diabetic Animal ◽  
In Vitro Tests ◽  
Diabetic Mice ◽  
Fossil Material ◽  
Expression Of Genes ◽  
Enhanced Expression ◽  
Genetically Diabetic Mice

Type II diabetes is a metabolic disease mediated through multiple molecular pathways. Here, we report anti-diabetic effect of a standardized isolate from a fossil material - a mineraloid leonardite - in in vitro tests and in genetically diabetic mice. The mineraloid isolate stimulated mitochondrial metabolism in human fibroblasts and this stimulation correlated with enhanced expression of genes coding for mitochondrial proteins such as ATP synthases and ribosomal protein precursors, as measured by DNA microarrays. In the diabetic animal model, consumption of the Totala isolate resulted in decreased weight gain, blood glucose, and glycated hemoglobin. To our best knowledge, this is the first description ever of a fossil material having anti-diabetic activity in pre-clinical models.

Comparison of High Purity Factor IX Concentrates and a Prothrombin Complex Concentrate in a Canine Model of Thrombogenicity

1991 ◽  
Vol 66 (05) ◽  
pp. 609-613 ◽  
Author(s):  
I R MacGregor ◽  
J M Ferguson ◽  
L F McLaughlin ◽  
T Burnouf ◽  
C V Prowse
Keyword(s):  
High Purity ◽  
Time Course ◽  
Prothrombin Complex Concentrate ◽  
Degradation Products ◽  
Canine Model ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Albumin Infusion

SummaryA non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.

A Comparison of the in Vitro and in Vivo Thrombogenic Activity of Factor IX Concentrates Using Stasis (Wessler) and Non-Stasis Rabbit Models

1980 ◽  
Vol 44 (02) ◽  
pp. 081-086 ◽  
Author(s):  
C V Prowse ◽  
A E Williams
Keyword(s):  
Platelet Rich Plasma ◽  
Thrombus Formation ◽  
Factor Ix ◽  
Coagulation System ◽  
In Vitro Tests ◽  
Clinical Use ◽  
Low Activity

SummaryThe thrombogenic effects of selected factor IX concentrates were evaluated in two rabbit models; the Wessler stasis model and a novel non-stasis model. Concentrates active in either the NAPTT or TGt50 in vitro tests of potential thrombogenicity, or both, caused thrombus formation in the Wessler technique and activation of the coagulation system in the non-stasis model. A concentrate with low activity in both in vitro tests did not have thrombogenic effects in vivo, at the chosen dose. Results in the non-stasis model suggested that the thrombogenic effects of factor IX concentrates may occur by at least two mechanisms. A concentrate prepared from platelet-rich plasma and a pyrogenic concentrate were also tested and found to have no thrombogenic effect in vivo.These studies justify the use of the NAPTT and TGt50 in vitro tests for the screening of factor IX concentrates prior to clinical use.

In Vitro Thrombogenicity Tests of Factor IX Concentrates

1979 ◽  
Vol 42 (05) ◽  
pp. 1355-1367 ◽  
Author(s):  
C V Prowse ◽  
A Chirnside ◽  
R A Elton
Keyword(s):  
Factor Viii ◽  
Partial Thromboplastin Time ◽  
Generation Time ◽  
Activated Partial Thromboplastin Time ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Factor Viii Inhibitor ◽  
Factor Ixa ◽  
Viii Inhibitor

SummaryVarious factor IX concentrates have been examined in a number of in vitro tests of thrombogenicity. The results suggest that some tests are superfluous as in concentrates with activity in any of these tests activation is revealed by a combination of the non-activated partial thromboplastin time, the thrombin (or Xa) generation time and factor VIII inhibitor bypassing activity tests. Assay of individual coagulant enzymes revealed that most concentrates contained more factor IXa than Xa. However only a small number of concentrates, chiefly those that had been purposefully activated, contained appreciable amounts of either enzyme.

Inhibition of Fibrinolysis and Fibrinogenolysis in Man: Comparison of ε-Aminocaproic Acid and Kallikrein Inhibitor

1963 ◽  
Vol 10 (01) ◽  
pp. 106-119 ◽  
Author(s):  
E Beck ◽  
R Schmutzler ◽  
F Duckert ◽  
Keyword(s):  
Aminocaproic Acid ◽  
Side Reactions ◽  
In Vitro Tests ◽  
Factor V ◽  
Clinical Use ◽  
Strong Inhibitor ◽  
Kallikrein Inhibitor ◽  
Therapeutic Possibilities

SummaryInhibitor of kallikrein and trypsin (KI) extracted from bovine parotis was compared with ε-aminocaproic acid (EACA): both substances inhibit fibrinolysis induced with streptokinase. EACA is a strong inhibitor of fibrinolysis in concentrations higher than 0, 1 mg per ml plasma. The same amount and higher concentrations are not able to inhibit completely the proteolytic-side reactions of fibrinolysis (fibrinogenolysis, diminution of factor V, rise of fibrin-polymerization-inhibitors). KI inhibits well proteolysis of plasma components in concentrations higher than 2,5 units per ml plasma. Much higher amounts of KI are needed to inhibit fibrinolysis as demonstrated by our in vivo and in vitro tests.Combination of the two substances for clinical use is suggested. Therapeutic possibilities are discussed.

Sign in / Sign up

Export Citation Format

Share Document