Novel Copper Nanoparticles Intercalated Polyurethane Heparin/Poly-L-Lysine Chelates Coated Stents: Viability Study for Coronary Vascular Cells and Aneurysms Treatments

2021 ◽  
Vol 17 (2) ◽  
pp. 216-229
Author(s):  
Ji Ma ◽  
Teng-Fei Li ◽  
Hui-Feng Yuan
Keyword(s):  
Cell Proliferation ◽  
Functional Group ◽  
Structural Characteristics ◽  
Cell Behavior ◽  
Vascular Cell ◽  
Coronary Artery Stent ◽  
Viability Study ◽  
The Stability ◽  
Cardiovascular Implants ◽  
Surface Geomorphology

Continuous delayed endothelium regeneration and continues thrombosis development designate a task for coronary artery stent rehabilitation. To progress the direct vascular cell behavior, aneurysms treatments and compatibility of cardiovascular implants novel copper intercalated polyurethane heparin/poly-L-lysine chelates treated stent has established in this report. The functional group modifications, structural characteristics, and stability of the chelates have investigated for polyurethane heparin: poly-L-lysine, copper intercalated polyurethane heparin/poly-L-lysine coated stents. The FTIR results showed the copper intercalation at 446 cmr and the Cu 2s peak at 932 eV from XPS also indicated that the successful coating of copper, polyurethane heparin, poly-L-lysine. The relative surface geomorphology of the chelates displayed the uniform Cu coating consisting of multilayer poly-L-lysine on the substrate. The stability and biocompatibility studies indicated the significantly enhanced performance with clot the APTT and TT periods as clotting and cell proliferation assessments. This type of composite proposes a stage on a stent external area for discerning track of vascular cell performance and aneurysms treatments with low side effects.

Catalytic Enantioselective Benzylation Directly from Aryl Acetic Acids

2018 ◽  
Author(s):  
Patrick Moon ◽  
Zhongyu Wie ◽  
Rylan Lundgren
Keyword(s):  
Functional Group ◽  
Terminal Event ◽  
Radical Intermediates ◽  
Carbon Carbon Bond ◽  
Or Groups ◽  
Reaction Proceeds ◽  
Wide Availability ◽  
Metal Catalyzed ◽  
The Stability ◽  
Acetic Acids

The stability and wide availability of carboxylic acids make them valuable reagents in chemical synthesis. Most transition metal catalyzed processes using carboxylic acid substrates are initiated by a decarboxylation event that generates reactive carbanion or radical intermediates. Developing enantioselective methodologies relying on these principles can be challenging, as highly reactive species tend to react indiscriminately without selectivity. Furthermore, anionic or radical intermediates generated from decarboxylation can be incompatible with protic and electrophilic functionality, or groups that undergo trapping with radicals. We demonstrate that metal-catalyzed enantioselective benzylation reactions of allylic electrophiles can occur directly from aryl acetic acids. The reaction proceeds via a pathway in which decarboxylation is the terminal event, occurring after stereoselective carbon–carbon bond formation. The mechanistic features of the process enable enantioselective benzylation without the generation of a highly basic nucleophile. Thus, the process has broad functional group compatibility that would not be possible employing established protocols.<br>

ROLE OF PAF AND OXIDANT AGENTS ON VASCULAR CELL PROLIFERATION. IN VITRO IMPLICATION OF MTOR-DEPENDENT PATHWAY.

2004 ◽  
Vol 78 ◽  
pp. 741-742
Author(s):  
I Rama ◽  
M Riera ◽  
J Torras ◽  
J M Cruzado ◽  
I Herrero-Fresneda ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Vascular Cell ◽  
Proliferation In Vitro ◽  
Dependent Pathway

scholarly journals Preparation and characteristics of gelatin sponges crosslinked by microbial transglutaminase

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3665 ◽  
Author(s):  
Haiyan Long ◽  
Kunlong Ma ◽  
Zhenghua Xiao ◽  
Xiaomei Ren ◽  
Gang Yang
Keyword(s):  
Cell Proliferation ◽  
Water Absorption ◽  
Crosslinking Agent ◽  
Microbial Transglutaminase ◽  
High Porosity ◽  
Cell Compatibility ◽  
High Viability ◽  
Good Biocompatibility ◽  
The Stability

Microbial transglutaminase (mTG) was used as a crosslinking agent in the preparation of gelatin sponges. The physical properties of the materials were evaluated by measuring their material porosity, water absorption, and elastic modulus. The stability of the sponges were assessed via hydrolysis and enzymolysis. To study the material degradation in vivo, subcutaneous implantations of sponges were performed on rats for 1–3 months, and the implanted sponges were analyzed. To evaluate the cell compatibility of the mTG crosslinked gelatin sponges (mTG sponges), adipose-derived stromal stem cells were cultured and inoculated into the scaffold. Cell proliferation and viability were measured using alamarBlue assay and LIVE/DEAD fluorescence staining, respectively. Cell adhesion on the sponges was observed by scanning electron microscopy (SEM). Results show that mTG sponges have uniform pore size, high porosity and water absorption, and good mechanical properties. In subcutaneous implantation, the material was partially degraded in the first month and completely absorbed in the third month. Cell experiments showed evident cell proliferation and high viability. Results also showed that the cells grew vigorously and adhered tightly to the sponge. In conclusion, mTG sponge has good biocompatibility and can be used in tissue engineering and regenerative medicine.

Vascular Cell Proliferation Dynamics: Implications for Gene Transfer and Restenosis

1997 ◽  
pp. 293-306 ◽  
Author(s):  
Robert S. Schwartz ◽  
Aloysius Chu ◽  
Myung Ho Jeong ◽  
Michael E. Staab ◽  
Sanjay S. Srivatsa ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Gene Transfer ◽  
Vascular Cell

scholarly journals Farms as a resilience factors to land degradation in peri-urban areas

2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
Paolo Zappavigna ◽  
Andrea Brugnoli
Keyword(s):  
Urban Areas ◽  
Structural Characteristics ◽  
Labour Force ◽  
Social Characteristics ◽  
The Family ◽  
External Conditions ◽  
Resilience Factors ◽  
The Stability ◽  
Economic Size

The purpose of this study was the analysis of the effects induced by urban pressures on the socio-economic and territorial characteristics of the rural peri-urban areas in order to identify planning and intervention strategies aimed at enhancing the quality of agriculture and landscape. A survey was conducted in the surroundings of Parma on farms located in the vicinity of urban areas. The structural, productive and social characteristics of the family-farm units were analyzed. The survey updated an identical survey, carried out in 1986, in which it was examined a sample of 208 farms. The units surveyed were evaluated in two aspects: the “vitality”, which takes into account the structural characteristics (size, production, labour force, etc.), and the “stability”, in which a crucial role is played by the age of the conductor and the presence of a successor. It was found that only 28% of the original farm sample is still alive, one third has disappeared, 30% was absorbed by existing farms, 8% has been abandoned. The factors most favourable to the survival resulted those referred to the vitality, especially the physical and economic size of the farm, the presence of cattle, the percentage of land in property, the presence of young labour. Among the factors that predispose to the abandonment, the urbanization processes were found to be determinants, in terms of expansion of both the built-up area and of that planned as urbanisable. The research has highlighted the importance of the vitality of the farms together with a context that has maintained its original rural features. These combined aspects can better define what we call the resiliency of the landfarms system i.e. the capability of positively reacting to the variable modifications of the internal and external conditions.

scholarly journals Synthesis and characterization of one-dimensional titanate structure

2008 ◽  
Vol 2 (2) ◽  
pp. 109-114 ◽  
Author(s):  
Ljubica Nikolic ◽  
Marija Maletin ◽  
Paula Ferreira ◽  
Paula Vilarinho
Keyword(s):  
Heat Treatment ◽  
Structural Characteristics ◽  
Hydrothermal Process ◽  
Synthesis And Characterization ◽  
One Dimensional ◽  
Treatment Conditions ◽  
Alkaline Conditions ◽  
The Stability ◽  
Simple Hydrothermal Process

One-dimensional titania structures were synthesized trough a simple hydrothermal process in a highly alkaline conditions. The aim of this work was to elucidate the effect of time on the formation of 1D titanates as well on its structural characteristics (morphology, phase composition, surface area). Apart from that, the effect of heat treatment conditions on the stability of titanate based 1D samples has been investigated. The results have revealed that it is possible to form one-dimensional titanates already after 1 hour of hydrothermal synthesis. Although the composition of titanates is still under debate, the results probably correspond to the layered sodium titanates. The 1D prepared structures show a remarkable stability during heating, remaining the basic morphology and composition even up to 700?C.

scholarly journals Water Softening Mechanism and Strength Model for Saturated Carbonaceous Mudstone in Panzhihua Airport, China

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Ziwen Wang ◽  
Jifang Du ◽  
Shuaifeng Wu ◽  
Yingqi Wei ◽  
Jianzhang Xiao ◽  
...  
Keyword(s):  
Shear Strength ◽  
Water Saturation ◽  
Structural Characteristics ◽  
Water Immersion ◽  
Analytical Techniques ◽  
Friction Angle ◽  
Mechanical Tests ◽  
Water Softening ◽  
Softening Mechanism ◽  
The Stability

To identify the water softening mechanisms that caused landslides in Panzhihua Airport, China, property and saturation tests of the mudstones extracted from a representative landslide were proposed. In this paper, water saturation tests were carried out on samples of carbonaceous mudstone collected from the east side of the No. 12 landslide at the airport. A number of different analytical techniques and mechanical tests were used to determine changes in chemical composition, mineral assemblages, and mudstone structural characteristics, including shear strength, after the mudstone had been softened. Three kinds of changes caused by water and three mudstone softening stages are proposed. The results show that the water has a significant influence on the properties of the mudstone, so the stability of the mudstone in the watery period is a big threat to the upper structure. A model for water immersion mudstone strength softening is developed. The model incorporates a permeability coefficient, the hydraulic gradient, and time; the model can be used to determine the mudstone’s shear strength and internal friction angle. This study provides a reference for the study of rock softened by water immersion.

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