scholarly journals In Vitro Cell Interactions on PVDF Films: Effects of Surface Morphology and Polar Phase Transition

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5232
Author(s):  
Marco A. Alvarez-Perez ◽  
Valentina Cirillo ◽  
Maria Giovanna Pastore Carbone ◽  
Marianna Pannico ◽  
Pellegrino Musto ◽  
...  
Keyword(s):  
Phase Transition ◽  
Cell Response ◽  
Polyvinylidene Fluoride ◽  
Piezoelectric Materials ◽  
Morphological Properties ◽  
In Vitro Tests ◽  
Process Conditions ◽  
Polar Phase ◽  
Electrical Stimuli

In recent years, several studies have validated the use of piezoelectric materials for in situ biological stimulation, opening new interesting insights for bio-electric therapies. In this work, we investigate the morphological properties of polyvinylidene fluoride (PVDF) in the form of microstructured films after temperature-driven phase transition. The work aims to investigate the correlations between morphology at micrometric (i.e., spherulite size) and sub-micrometric (i.e., phase crystallinity) scale and in vitro cell response to validate their use as bio-functional interfaces for cellular studies. Morphological analyses (SEM, AFM) enabled evidence of the peculiar spherulite-like structure and the dependence of surface properties (i.e., intra-/interdomain roughness) upon process conditions (i.e., temperature). Meanwhile, chemical (i.e., FTIR) and thermal (i.e., DSC) analyses highlighted an influence of casting temperature and polymer solution on apolar to polar phases transition, thus affecting in vitro cell response. Accordingly, in vitro tests confirmed the relationship between micro/sub-microstructural properties and hMSC response in terms of adhesion and viability, thus suggesting a promising use of PVDF films to model, in perspective, in vitro functionalities of cells under electrical stimuli upon mechanical solicitation.

Preparation and Characterization of Fibrous Hydroxyapatite/Chitosan Nanocomposites with High Hydroxyapatite Dosage

2012 ◽  
Vol 457-458 ◽  
pp. 365-371 ◽  
Author(s):  
Cai Yun Zhang ◽  
Dai Yin Peng ◽  
Chuan Hua Lu ◽  
Xian Ping Wang ◽  
Qian Feng Fang
Keyword(s):  
Morphological Properties ◽  
In Vitro Tests ◽  
X Ray Diffraction ◽  
Permeable Membrane ◽  
X Ray ◽  
Chitosan Matrix ◽  
Transmission Electron

In this paper the hydroxyapatite fibers reinforced chitosan nanocomposites with high hydroxyapatite dosage (70~90 wt%) were synthesized by in-situ hybridization. The semi-permeable membrane was used to control the process of hybridization and morphology of hydroxyapatite. The compositional and morphological properties of nanocomposites were investigated by FTIR spectroscopy, X-ray diffraction, and transmission electron microscopy. The results showed that the hydroxyapatite were carbonated nanometer crystalline fibers with high aspect ratio (about 25) and dispersed uniformly in the nanocomposites. The high-resolution image indicated that the growth of nano-hydroxyapatite crystallites in the chitosan matrix preferred in the c-axis. The mechanical properties of these nanocomposites were enhanced dramatically and the compressive strength increases almost to 170MPa when the hydroxyapatite content is 70 wt%. The in vitro tests indicated that the composites have high bioactivity and degradation. These properties illustrated the potential application of this kind of nanocomposites for bone tissue engineering.

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.

Fruit Volatiles to Control Postharvest Rot of Stone Fruits and Pears

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 469a-469
Author(s):  
L.J. Skog ◽  
D.P. Murr ◽  
B.E. Digweed
Keyword(s):  
Volatile Compounds ◽  
Isoamyl Acetate ◽  
Penicillium Expansum ◽  
Effective Control ◽  
In Vitro Tests ◽  
Stone Fruits ◽  
In Situ Tests ◽  
Highly Effective ◽  
Postharvest Rot

Volatile compounds are ubiquitous in plants, giving fruits their characteristic aroma and flavor. There is increasing evidence that these compounds can protect plants from pathogenic organisms. In this trial ≈25 volatile compounds were tested for efficacy against Monilinia fructicola and Penicillium expansum. Both in vitro tests on agar plugs of actively growing pathogens and in situ tests on inoculated stone fruits and pears were conducted. The volatile compounds were grouped into three categories based upon fungicidal activity in vitro: highly effective (fungicidal concentration ≤100 M), moderately effective (fungicidal concentration between 100–200 M) and ineffective (fungicidal concentration >200 M). Highly effective compounds included: acetaldehyde, citral, 2-ethyl-1-hexanol, 2,exadienal, E-2-hexenal, 4-hexen-3-one, linalool, (E,E)2,4-nonadienal, E-2-nonenal, E-3-none-2-one, salicylaldehyde, and valeraldehyde. Moderately effective compounds included: (E,Z) 2,6-nonadienal, propionaldehyde, terpinene, butyl acetate, E-cinnamaldehde, hexanal, E-2-hexen-1-ol, Z-3-hexen-1-ol and isoamyl acetate. Ineffective compounds included: butyrolactone, ethanol, ethyl acetate, and methyl acetate. Effectiveness of the compounds varied with both strain and type of microorganism tested. Concentraions required for effective control were much higher when the compounds were tested on inoculated fruit. Phytotoxicity was a problem with some compounds.

Role of in vivo and in vitro Tests in the Diagnosis of Severe Cutaneous Adverse Reactions (SCAR) to Drug

2019 ◽  
Vol 25 (36) ◽  
pp. 3872-3880 ◽  
Author(s):  
Marcel M. Bergmann ◽  
Jean-Christoph Caubet
Keyword(s):  
Adverse Reactions ◽  
Lymphocyte Transformation ◽  
Stevens Johnson Syndrome ◽  
In Vitro Tests ◽  
High Morbidity ◽  
Patch Tests ◽  
Severe Cutaneous Adverse Reactions ◽  
Cutaneous Adverse Reactions

Severe cutaneous adverse reactions (SCAR) are life-threatening conditions including acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS). Diagnosis of causative underlying drug hypersensitivity (DH) is mandatory due to the high morbidity and mortality upon re-exposure with the incriminated drug. If an underlying DH is suspected, in vivo test, including patch tests (PTs), delayed-reading intradermal tests (IDTs) and in vitro tests can be performed in selected patients for which the suspected culprit drug is mandatory, or in order to find a safe alternative treatment. Positivity of in vivo and in vitro tests in SCAR to drug varies depending on the type of reaction and the incriminated drugs. Due to the severe nature of these reactions, drug provocation test (DPT) is highly contraindicated in patients who experienced SCAR. Thus, sensitivity is based on positive test results in patients with a suggestive clinical history. Patch tests still remain the first-line diagnostic tests in the majority of patients with SCAR, followed, in case of negative results, by delayed-reading IDTs, with the exception of patients with bullous diseases where IDTs are still contra-indicated. In vitro tests have shown promising results in the diagnosis of SCAR to drug. Positivity is particularly high when the lymphocyte transformation test (LTT) is combined with cytokines and cytotoxic markers measurement (cyto-LTT), but this still has to be confirmed with larger studies. Due to the rarity of SCAR, large multi-center collaborative studies are needed to better study the sensitivity and specificity of in vivo and in vitro tests.

Injectable in-situ Forming Depot Of Doxycycline Hyclate/α-Cyclodextrin Complex using PLGA for Periodontitis Treatment: Preparation, Charac-terization, and In-Vitro Evaluation

2020 ◽  
Vol 17 ◽  
Author(s):  
Elham Khodaverdi ◽  
Farhad Eisvand ◽  
Mohammad Sina Nezami ◽  
Seyedeh Nesa Rezaeian Shiadeh ◽  
Hossein Kamali ◽  
...  
Keyword(s):  
Complex Form ◽  
Docking Studies ◽  
Morphological Properties ◽  
Burst Release ◽  
Cyclodextrin Complex ◽  
Doxycycline Hyclate ◽  
Scanning Calorimetry ◽  
In Situ Forming

Background:: Doxycycline (DOX) is used in treating a bacterial infection, especially for periodontitis treatment. Objective: To reduce irritation of DOX for subgingival administration and increase the chemical stability and against enzy-matic, the complex of α-cyclodextrin with DOX was prepared and loaded into injectable in situ forming implant based on PLGA. Methods:: FTIR, molecular docking studies, X-ray diffraction, and differential scanning calorimetry was performed to char-acterize the DOX/α-cyclodextrin complex. Finally, the in-vitro drug release and modeling, morphological properties, and cellular cytotoxic effects were also evaluated. Results:: The stability of DOX was improved with complex than pure DOX. The main advantage of the complex is the al-most complete release (96.31 ± 2.56 %) of the drug within 14 days of the implant, whereas in the formulation containing the pure DOX and the physical mixture the DOX with α-cyclodextrin release is reached to 70.18 ± 3.61 % and 77.03 ± 3.56 %, respectively. This trend is due to elevate of DOX stability in the DOX/ α-cyclodextrin complex form within PLGA implant that confirmed by the results of stability. Conclusion:: Our results were indicative that the formulation containing DOX/α-cyclodextrin complex was biocompatible and sustained-release with minimum initial burst release.

Antimutagenic, Antiproliferative and Antioxidant Properties of Sea Grape Leaf Extract Fractions (Coccoloba uvifera L.)

2021 ◽  
Vol 21 ◽  
Author(s):  
Jorge A. Ramos-Hernández ◽  
Montserrat Calderón-Santoyo ◽  
Armando Burgos-Hernández ◽  
Joel S. García- Romo ◽  
Arturo Navarro-Ocaña ◽  
...  
Keyword(s):  
Antioxidant Properties ◽  
In Vitro Tests ◽  
Antimutagenic Activity ◽  
Hexane Extraction ◽  
Biological Potential ◽  
Hct 116 ◽  
Pharmaceutical Industries ◽  
Grape Leaf ◽  
First Time

Background: Cancer is a disease characterized by the invasion and uncontrolled growth of cells. One of the best ways to minimize the harmful effects of mutagens is through the use of natural antimutagens. In this regard, the search for new antimutagens that act in the chemoprevention could represent a promising field in this area. Objective: In this study biological potential of 11 fractions from Coccoloba uvifera L. leaf hexane extract was evaluated by several in vitro tests. Methods: Leaves were lyophilized and hexane extraction was performed. The extract was fractionated by column chromatography with hexane, ethyl acetate, and methanol. The antimutagenic (Ames test), antiproliferative (MTT test), and antioxidant capacity (DPPH, ABTS, and ferrous ion chelation) of the fractions were evaluated. Results: Fractions 4, 6, 8, and 9 have antimutagenic activity (against sodium azide in strain TA100), fraction 11 showed antiproliferative capacity (IC50 of 24 ± 9 μg/mL in cells of HCT 116). The fractions with the highest activity were analyzed by HPLC-MS and lupeol, acacetin, and β-sitosterol were identified. Conclusion: This study demonstrates, for the first time, the bioactivity of C. uvifera leaf as a new source of high biological value compounds (HBVC), which can be of interest to the food and pharmaceutical industries.

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