scholarly journals Influence of Hydroxyapatite Nanoparticles and Surface Plasma Treatment on Bioactivity of Polycaprolactone Nanofibers

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1877
Author(s):  
Eva Stastna ◽  
Klara Castkova ◽  
Jozef Rahel
Keyword(s):  
Cell Proliferation ◽  
Plasma Treatment ◽  
Discharge Plasma ◽  
Hydroxyapatite Nanoparticles ◽  
Surface Plasma ◽  
Natural Polymers ◽  
Plasma Surface Treatment ◽  
Argon Discharge ◽  
Electrospinning Method ◽  
The Impact

Nanofibers are well known as a beneficial type of structure for tissue engineering. As a result of the high acquisition cost of the natural polymers and their environmentally problematic treatment (toxic dissolution agents), artificial polymers seem to be the better choice for medical use. In the present study, polycaprolactone nano-sized fibrous structures were prepared by the electrospinning method. The impact of material morphology (random or parallelly oriented fibers versus continuous layer) and the presence of a fraction of hydroxyapatite nanoparticles on cell proliferation was tested. In addition, the effect of improving the material wettability by a low temperature argon discharge plasma treatment was evaluated, too. We have shown that both hydroxyapatite particles as well as plasma surface treatment are beneficial for the cell proliferation. The significant impact of both influences was evident during the first 48 h of the test: the hydroxyapatite particles in polycaprolactone fibers accelerated the proliferation by 10% compared to the control, and the plasma-treated ones enhanced proliferation by 30%.

scholarly journals Enhanced Wetting and Adhesive Properties by Atmospheric Pressure Plasma Surface Treatment Methods and Investigation Processes on the Influencing Parameters on HIPS Polymer

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 901
Author(s):  
Miklós Berczeli ◽  
Zoltán Weltsch
Keyword(s):  
Surface Treatment ◽  
Plasma Treatment ◽  
Atmospheric Pressure ◽  
High Impact ◽  
Plasma Parameters ◽  
Plasma Surface ◽  
Wetting Properties ◽  
High Impact Polystyrene ◽  
Process Modification ◽  
Plasma Surface Treatment

The development of bonding technology and coating technologies require the use of modern materials and topologies for the demanding effect and modification of their wetting properties. For the industry, a process modification process that can be integrated into a process is the atmospheric pressure of air operation plasma surface treatment. This can be classified and evaluated based on the wettability, which has a significant impact on the adhesive force. The aim is to improve the wetting properties and to find the relationship between plasma treatment parameters, wetting, and adhesion. High Impact PolyStyrene (HIPS) was used as an experimental material, and then the plasma treatment can be treated with various adjustable parameters. The effect of plasma parameters on surface roughness, wetting contact angle, and using Fowkes theory of the surface energy have been investigated. Seven different plasma jet treatment distances were tested, combined with 5 scan speeds. Samples with the best plasma parameters were prepared from 25 mm × 25 mm overlapping adhesive joints using acrylic/cyanoacrylate. The possibility of creating a completely hydrophilic surface was achieved, where the untreated wetting edge angle decreased from 88.2° to 0° for distilled water and from 62.7° to 0° in the case of ethylene glycol. The bonding strength of High Impact PolyStyrene was increased by plasma treatment by 297%.

scholarly journals Treatment of wood with atmospheric plasma discharge: study of the treatment process, dynamic wettability and interactions with a waterborne coating

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Jure Žigon ◽  
Matjaž Pavlič ◽  
Pierre Kibleur ◽  
Jan Van den Bulcke ◽  
Marko Petrič ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Treatment Process ◽  
Beech Wood ◽  
Treated Wood ◽  
Plasma Discharge ◽  
Contact Angles ◽  
Atmospheric Plasma ◽  
Waterborne Coating ◽  
Spruce Wood ◽  
The Impact

AbstractPlasma treatment is becoming a mature technique for modification of surfaces of various materials, including wood. A better insight in the treatment process and the impact of the plasma on properties of wood bulk are still needed. The study was performed on Norway spruce and common beech wood, as well as their thermally modified variations. The formations of the airborne discharge, as well as mass changes of the treated wood, were monitored. The impact of such treatment on wood-coating interaction was investigated by evaluating the dynamic wettability and penetration into wood. At the wood surface, plasma streamers were observed more intense on denser latewood regions. Wood mass loss was higher with increasing number of passes through the plasma discharge and was lower for thermally modified wood than for unmodified wood. Plasma treatment increased the surface free energy of all wood species and lowered the contact angles of a waterborne coating, these together indicating enhanced wettability after treatment. Finally, the distribution and penetration depth of the coating were studied with X-ray microtomography. It was found that the coating penetrated deeper into beech than into spruce wood. However, the treatment with plasma increased the penetration of the coating only into spruce wood.

scholarly journals Keratinocytes Regulate the Threshold of Inflammation by Inhibiting T Cell Effector Functions

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1606
Author(s):  
Peter Seiringer ◽  
Stefanie Eyerich ◽  
Kilian Eyerich ◽  
Daniela Dittlein ◽  
Anna Caroline Pilz ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
T Cell ◽  
Cytokine Production ◽  
Nickel Sulfate ◽  
Human Keratinocytes ◽  
T Cell Proliferation ◽  
Effector Functions ◽  
The Impact ◽  
Cell Effector

Whilst the importance of keratinocytes as a first-line defense has been widely investigated, little is known about their interactions with non-resident immune cells. In this study, the impact of human keratinocytes on T cell effector functions was analyzed in an antigen-specific in vitro model of allergic contact dermatitis (ACD) to nickel sulfate. Keratinocytes partially inhibited T cell proliferation and cytokine production. This effect was dependent on the keratinocyte/T cell ratio and was partially reversible by increasing the number of autologous dendritic cells. The inhibition of T cell proliferation by keratinocytes was independent of the T cell subtype and antigen presentation by different professional antigen-presenting cells. Autologous and heterologous keratinocytes showed comparable effects, while the fixation of keratinocytes with paraformaldehyde abrogated the immunosuppressive effect. The separation of keratinocytes and T cells by a transwell chamber, as well as a cell-free keratinocyte supernatant, inhibited T cell effector functions to the same amount as directly co-cultured keratinocytes, thus proving that soluble factor/s account for the observed suppressive effects. In conclusion, keratinocytes critically control the threshold of inflammatory processes in the skin by inhibiting T cell proliferation and cytokine production.

Impact of the cystic fibrosis mutation F508del-CFTR on renal cyst formation and growth

2012 ◽  
Vol 303 (8) ◽  
pp. F1176-F1186 ◽  
Author(s):  
Hongyu Li ◽  
Wanding Yang ◽  
Filipa Mendes ◽  
Margarida D. Amaral ◽  
David N. Sheppard
Keyword(s):  
Cystic Fibrosis ◽  
Cell Proliferation ◽  
Mdck Cells ◽  
Ussing Chamber ◽  
Cyst Formation ◽  
Transepithelial Resistance ◽  
Collagen Gels ◽  
Wild Type ◽  
Fluid Accumulation ◽  
The Impact

In autosomal dominant polycystic kidney disease (ADPKD), cystic fibrosis transmembrane conductance regulator (CFTR), the protein product of the gene defective in cystic fibrosis (CF), plays a crucial role in fluid accumulation, which promotes cyst swelling. Several studies have identified individuals afflicted by both ADPKD and CF. Two studies suggested that CF mutations might attenuate the severity of ADPKD, whereas a third found no evidence of a protective effect. In this study, we investigated the impact of the commonest CF mutation F508del-CFTR on the formation and growth of renal cysts. As a model system, we used Madin-Darby canine kidney (MDCK) epithelial cells engineered to express wild-type and F508del human CFTR. We grew MDCK cysts in collagen gels in the presence of the cAMP agonist forskolin and measured transepithelial resistance and Cl− secretion with the Ussing chamber technique and assayed cell proliferation using nonpolarized MDCK cells. When compared with untransfected MDCK cells, cells expressing wild-type CFTR generated substantial numbers of large cysts, which grew markedly over time. By contrast, MDCK cells expressing F508del-CFTR formed very few tiny cysts that failed to enlarge. Interestingly, treatment of F508del-CFTR cysts with the CFTR corrector VRT-325 and the CFTR corrector-potentiator VRT-532 increased the number, but not size, of F508del-CFTR cysts, possibly because VRT-325 inhibited strongly cell proliferation. Based on its effects on transepithelial resistance, Cl− secretion, and cell proliferation, we conclude that the F508del-CFTR mutation disrupts cyst formation and growth by perturbing strongly fluid accumulation within the cyst lumen without compromising epithelial integrity.

Effect of the RF-discharge plasma treatment of thin polyimide films on water diffusion

2005 ◽  
Vol 39 (3) ◽  
pp. 192-195 ◽  
Author(s):  
S. A. Zhukova ◽  
A. A. Zhukov ◽  
A. I. Drachev
Keyword(s):  
Plasma Treatment ◽  
Discharge Plasma ◽  
Water Diffusion ◽  
Rf Discharge ◽  
Polyimide Films

scholarly journals In vitro anticancer activity of hydrogen sulfide and nitric oxide alongside nickel nanoparticle and novel mutations in their genes in CRC patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zjwan Housein ◽  
Tayeb Sabir Kareem ◽  
Abbas Salihi
Keyword(s):  
Nitric Oxide ◽  
Cell Proliferation ◽  
Hydrogen Sulfide ◽  
Direct Sequencing ◽  
Scorpion Venom ◽  
Enos Gene ◽  
Cytotoxic Activities ◽  
No Donors ◽  
The Impact

AbstractThis study was carried out to assess the impact of nickel nanoparticles (NiNPs) as well as scorpion venom on colorectal cancer (CRC) cells in the presence and/or absence of 5-fluorouracil (5-FU), hydrogen sulfide (H2S), and nitric oxide (NO) donors and to determine alterations in endothelial NO synthase (eNOS) and cystathionine γ-lyase (CSE) enzyme-producing genes in CRC patients. The IC50 of both H2S and NO donors, along with NiNPs, were determined. The CRC cells were treated for 24hrs, and the cytotoxic activities were assessed using the MTT test. Moreover, the apoptosis was determined after 24hrs and 48hrs using TUNEL assay. Furthermore, the mutations in the eNOS gene (intron 4, -786T>C and 894 G>T) and CSE gene (1364GT) were determined using direct sequencing. The IC50 values for sodium disulfide (Na2S) and sodium nitroprusside (SNP) at 24hrs treatment were found to be 5 mM and 10−6 M, respectively, while the IC50 value for 5-FU was reached after 5-days of treatment in CRC cell line. Both black and yellow scorpion venoms showed no inhibition of cell proliferation after 24hrs treatment. Furthermore, Na2S showed a significant decrease in cell proliferation and an increase in apoptosis. Moreover, a co-treatment of SNP and 5-FU resulted in inhibition of the cytotoxic effect of 5-FU, while a combination treatment of NiNPs with Na2S, SNP, and 5-FU caused highly significant cytotoxicity. Direct sequencing reveals new mutations, mainly intronic variation in eNOS gene that has not previously been described in the database. These findings indicate that H2S promotes the anticancer efficiency of 5-FU in the presence of NiNPs while NO has antiapoptotic activity in CRC cell lines.

The impact of the workability of an automated technological system on the effective implementation of the production program when processing tools in glow discharge plasma generators

2021 ◽  
pp. 58-65
Author(s):  
V.A. Logvin ◽  
◽  
S.A. Sheptunov ◽  
Keyword(s):  
Glow Discharge ◽  
Discharge Plasma ◽  
Functional Dependence ◽  
Plasma Generator ◽  
Glow Discharge Plasma ◽  
Optimal Time ◽  
Time Interval ◽  
Production Program ◽  
The Impact ◽  
Plasma Generators

The conditions for the hardening of tools in accordance with the author’s technological routes in the optimal time interval are considered using the functional dependence of the serviceability of plasma generators. This dependence takes into account the workability of the technical devices involved in processing the laying batch of tools in the speci ed time interval. The probability of performing the production process in the estimated time is represented by the product of the trouble-free operation of each glow discharge plasma generator involved in the nishing processing of tools that require a different type of plasma exposure in a certain sequence and duration.

Abstract 160: Pim-1 Preserves Cardiac Stem Cell Proliferation with Age

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Michael McGregor ◽  
Shabana Din ◽  
Natalie Gude ◽  
Mark A Sussman
Keyword(s):  
Cell Proliferation ◽  
Stem Cell ◽  
Time Course ◽  
Protein A ◽  
Cell Types ◽  
Tissue Homeostasis ◽  
Dominant Negative ◽  
Repair Capacity ◽  
Tissue Samples ◽  
The Impact

Rationale Cardiac stem cells (CSC) regulate cardiomyogenesis and support regenerative processes in the heart, but aging adversely affects stem cell repair capacity. Aging is a primary cause of impaired cardiac function characterized by accumulation of senescent cells. CSC senescence is associated with permanent growth arrest that decreases survival signaling and cellular replacement, inevitably diminishing the capacity of the heart to maintain tissue homeostasis. Therefore, promoting CSC growth may improve cardiac performance with age. Pim-1 kinase exhibits protective and proliferative effects in the myocardium but the role of Pim-1 in cardiac aging has not been thoroughly studied. Objective Demonstrate that Pim-1 promotes stem cell growth in the aged myocardium correlating with increased expression of centromere protein A (CENP-A), a kinetochore-associated protein known to support cell proliferation in numerous species and cell types. Methods & Results CENP-A expression levels were evaluated from murine myocardial tissue samples ranging in age from 11 days post coitum to 4 months of age with analysis by immunoblot as well as quantitative PCR. CENP-A expression was colocalized with c-kit as a marker of CSC by immunohistochemical labeling, revealing a decline in CENP-A expression over the time course of postnatal myocardial maturation. The impact of Pim-1 upon CENP-A level was assessed by comparative analysis of non-transgenic mice versus genetically modified transgenic mouse lines expressing either Pim-1 (wild type) or a dominant negative functionally dead Pim-1 mutant. Pim-1 overexpression increases persistence of CENP-A in CSCs with age, as well as the prevalence of cycling CSCs as marked by phosph-H3 expression, while the functionally dead mutant accelerates CENP-A diminution and decreases CSC proliferation. Conclusion CENP-A decline in c-kit positive cells with age provides intriguing evidence of a potential mechanism for the diminished capacity of CSCs to maintain tissue homeostasis. Pim-1 mitigates CENP-A diminution, demonstrating the promising potential of Pim-1 to promote cardiac growth and repair with age.

The Impact Evaluation of Factors on the Adhesion of Modified Polytetrafluoroethylene Films in a Glow Discharge Non-Thermal Plasma

2020 ◽  
Vol 992 ◽  
pp. 658-662
Author(s):  
M.A. Mokeev ◽  
L.A. Urkhanova ◽  
A.N. Khagleev ◽  
Denis B. Solovev
Keyword(s):  
Glow Discharge ◽  
Plasma Treatment ◽  
Thermal Plasma ◽  
Graphical Model ◽  
Polymer Surface ◽  
Practical Method ◽  
Wetting Angle ◽  
Regression Equations ◽  
Non Thermal Plasma ◽  
The Impact

Mechanical, chemical and plasma treatment are the main kind of treatment of polytetrafluoroethylene (PTFE) films. Each method is different from each other by the adhesive force: the value of the wetting angle. Mechanical treatment allows different particles to permeate into the structure of the polymer. Chemical treatment creates new functional groups on the polymer surface, but this method is toxic and dangerous. Plasma treatment, in a glow discharge non-thermal plasma, is a more ecological and practical method. The experiment showed that the plasma treatment successfully increases the adhesion, this has been proven by infrared spectroscopy and scanning electron microscopy. According to the obtained data of the wetting angle, the regression equation was derived. A graphical model is constructed by regression equations allows you to determine the main processing factor and choose the optimal values of treatment.

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