Platelet-Released Growth Factors Influence Wound Healing-Associated Genes in Human Keratinocytes and Ex Vivo Skin Explants

Platelet-released growth factors (PRGFs) or other thrombocyte concentrate products, e.g., Platelet-Rich Fibrin (PRF), have become efficient tools of regenerative medicine in many medical disciplines. In the context of wound healing, it has been demonstrated that treatment of chronic or complicated wounds with PRGF or PRF improves wound healing in the majority of treated patients. Nevertheless, the underlying cellular and molecular mechanism are still poorly understood. Therefore, we aimed to analyze if PRGF-treatment of human keratinocytes caused the induction of genes encoding paracrine factors associated with successful wound healing. The investigated genes were Semaphorin 7A (SEMA7A), Angiopoietin-like 4 (ANGPLT4), Fibroblast Growth Factor-2 (FGF-2), Interleukin-32 (IL-32), the CC-chemokine-ligand 20 (CCL20), the matrix-metalloproteinase-2 (MMP-2), the chemokine C-X-C motif chemokine ligand 10 (CXCL10) and the subunit B of the Platelet-Derived Growth Factor (PDGFB). We observed a significant gene induction of SEMA7A, ANGPLT4, FGF-2, IL-32, MMP-2 and PDGFB in human keratinocytes after PRGF treatment. The CCL20- and CXCL10 gene expressions were significantly inhibited by PRGF therapy. Signal transduction analyses revealed that the PRGF-mediated gene induction of SEMA7A, ANGPLT4, IL-32 and MMP-2 in human keratinocytes was transduced via the IL-6 receptor pathway. In contrast, EGF receptor signaling was not involved in the PRGF-mediated gene expression of analyzed genes in human keratinocytes. Additionally, treatment of ex vivo skin explants with PRGF confirmed a significant gene induction of SEMA7A, ANGPLT4, MMP-2 and PDGFB. Taken together, these results describe a new mechanism that could be responsible for the beneficial wound healing properties of PRGF or related thrombocytes concentrate products such as PRF.     

Surface modification of graphite encapsulated iron nanoparticles by plasma processing

The graphite encapsulated iron nanoparticles were fabricated by using arc discharge method. The synthesized nanoparticles were pre-treated by an inductively-coupled RF Ar plasma and then post-treated by NH₃ plasma under various gas pressures and treatment times. Analyses of XPS spectra have been carried out to study the effect of the plasma treatment on the surface modification of nitrogen-containing groups. The morphological changes of the particles surface by plasma treatment have also been analyzed by using HR-TEM. Present results show that the highest values of N/C atomic ratio of 5.4 % is obtained by applying 10 min of Ar plasma pre-treatment and 2 min of NH₃ plasma post-treatment conducted in RF power of 80 W and gas pressure of 50 Pa.     

Atmospheric pressure plasma surface modification of titanium for high temperature adhesive bonding

In this investigation surface treatment of titanium is carried out by plasma ion implantation under atmospheric pressure plasma in order to increase the adhesive bond strength. Prior to the plasma treatment, titanium surfaces were mechanically treated by sand blasting. It is observed that the contact angle of de-ionized water decreases with the grit blast treatment time. Optical microscopy and scanning electron microscopic (SEM) analysis of untreated and atmospheric plasma treated titanium are carried out to examine the surface characteristics. A substantial improvement in the surface energy of titanium is observed after the atmospheric pressure plasma treatment. The surface energy increases with increasing exposure time of atmospheric pressure plasma. The optimized time of plasma treatment suggested in this investigation results in maximum adhesive bond strength of the titanium. Unmodified and surface modified titanium sheets by atmospheric pressure plasma were adhesively bonded by high temperature resistant polyimide adhesive. The glass transition temperature of this adhesive is 310 °C and these adhesively bonded joints were cured at high temperature. A substantial improvement in adhesive bond strength was observed after atmospheric pressure plasma treatment.     

基于等离子火炬的C/C复合材料烧蚀实验及理论研究

基于等离子火炬进行了C/C复合材料烧蚀实验,获得了材料的烧蚀表面形态及烧蚀产物光谱,确定了等离子火炬务件下的典型烧蚀产物.同时基于JANAF数据,通过最小能量法计算了等离子火炬低压高焓状态的热化学烧蚀产物,与光谱检测结果基本一致.     

Hip Osteoarthritis in Dogs: A Randomized Study Using Mesenchymal Stem Cells from Adipose Tissue and Plasma Rich in Growth Factors

Purpose: The aim of this study was to compare the efficacy and safety of a single intra-articular injection of adipose mesenchymal stem cells (aMSCs) versus plasma rich in growth factors (PRGF) as a treatment for reducing symptoms in dogs with hip osteoarthritis (OA). Methods: This was a randomized, multicenter, blinded, parallel group. Thirty-nine dogs with symptomatic hip OA were assigned to one of the two groups, to receive aMSCs or PRGF. The primary outcome measures were pain and function subscales, including radiologic assessment, functional limitation and joint mobility. The secondary outcome measures were owners’ satisfaction questionnaire, rescue analgesic requirement and overall safety. Data was collected at baseline, then, 1, 3 and 6 months post-treatment. Results: OA degree did not vary within groups. Functional limitation, range of motion (ROM), owner’s and veterinary investigator visual analogue scale (VAS), and patient’s quality of life improved from the first month up to six months. The aMSCs group obtained better results at 6 months. There were no adverse effects during the study. Our findings show that aMSCs and PRGF are safe and effective in the functional analysis at 1, 3 and 6 months; provide a significant improvement, reducing dog’s pain, and improving physical function. With respect to basal levels for every parameter in patients with hip OA, aMSCs showed better results at 6 months.     

等离子体诱导下丙烯酸在PET表面的接枝聚合

利用等离子体对聚对苯二甲酸乙二酯（PET）薄膜进行表面处理,并诱导引发丙烯酸（AAc）在其表面接枝聚合,制备了具有结合牢固、高亲水性的聚丙烯酸（PAAc-g-PET）复合膜。通过表面衰减全反射-傅里叶红外光谱（ATR-FTIR）结构表征,证明了PAAc成功接枝到PET薄膜上。通过对AAc在PET薄膜表面接枝率的动力学影响因素的系统分析,获得了高接枝率下的PAAc-g-PET复合膜的最佳实现条件。     

远程等离子体处理活性炭纤维及其高功能化研究

活性炭纤维的吸附性能和其表面官能团密切相关．远程等离子体处理是活性炭纤维获得更好的表面改性的新方法。为了提高活性炭纤维对水中有机污染物的吸附性能,本文对粘胶基活性炭纤维进行了远程等离子体表面改性,探讨等离子体处理时间,远程区距离对活性炭纤维的减重率及吸附性能的影响．结果表明,在远程区等离子体中电子离子对样品的刻蚀作用被抑制,同时远程区等离子体处理的吸附荆对水中有机污染物的去除效果优于未处理试样．     

高分子材料表面改性新技术

综述了近年来高分子材料表面改性新技术--等离子体技术表面改性高分子材料的最新进展.运用等离子体技术改变高分子材料的表面性质的方法主要有三类:等离子体处理、等离子体聚合和等离子体接枝聚合.等离子体技术正以其优越性在高聚物材料表面改性方面得到越来越广泛的应用.     

射流等离子体放电气氛对木塑复合材料表面性质的影响

利用空气、氮气、氧气3种不同气氛的射流等离子体放电对聚乙烯木塑复合材料（PE-WPC）表面进行处理以改善其胶接性能，其中空气、氮气、氧气气氛处理后的试样分别记为PE-WPC-A、PE-WPC-N和PE-WPC-O。通过对剪切强度、表面接触角、表面形貌、表面官能团以及表面元素含量的测试与表征，研究了不同气氛射流等离子体处理对PE-WPC表面物理化学性质的影响。研究结果表明：射流等离子体处理可以通过改变PE-WPC的表面性质，进而大幅度提高材料的胶接剪切强度，由未处理样品的0.62 MPa提高到处理后试样的11.32~13.79 MPa。对于胶接性能来说，不同气氛的射流等离子体处理效果差别不大；而对于处理后材料表面的微观结构，不同气氛射流等离子体的处理效果存在差别，氮气气氛处理以表面化学改性为主，在材料表面引入更多的含氮基团；氧气气氛处理以表面氧化刻蚀为主，在材料表面引入更多含氧基团；空气气氛处理则是以上2种作用的综合体现。     

Atmospheric plasma modification of polyimide sheet for joining to titanium with high temperature adhesive

This investigation highlights the rationale of adhesive bonding of atmospheric pressure plasma treated high temperature resistant polymeric sheet such as polyimide sheet (Meldin 7001), with titanium sheets. The surface of polyimide (PI) sheet was treated with atmospheric pressure plasma for different exposure times. The surface energy was found to increase with increase in exposure time. However, longer exposure time of plasma, results in deterioration of the surface layer of PI resulting in degradation and embrittlement.Contact angle measurements with sessile drop technique were carried out for estimation of surface energy. SEM (EDS) and AFM analyses of treated and untreated specimens were carried out to examine the surface characteristics and understanding morphological changes following surface treatment. Untreated samples and atmospheric pressure plasma treated samples of polyimide Meldin 7001 sheet were bonded together as well as with titanium substrates to form overlap joints. Single lap shear tensile testing of these adhesively bonded joints was performed to measure bond strength and to investigate the effect of surface treatment on adhesive bond strength. An optimized plasma treatment time results in maximum adhesive bond strength and consequently, this technology is highly acceptable for aviation and space applications.     

Astragaloside IV Attenuates Ocular Hypertension in a Mouse Model of TGFβ2 Induced Primary Open Angle Glaucoma

Elevated intraocular pressure (IOP) is a major risk factor in developing primary open angle glaucoma (POAG), which is the most common form of glaucoma. Transforming growth factor-beta 2 (TGFβ2) is a pro-fibrotic cytokine that plays an important role in POAG pathogenesis. TGFβ2 induced extracellular matrix (ECM) production, deposition and endoplasmic reticulum (ER) stress in the trabecular meshwork (TM) contribute to increased aqueous humor (AH) outflow resistance and IOP elevation. Drugs which alter the glaucomatous fibrotic changes and ER stress in the TM may be effective in reducing ocular hypertension. Astragaloside IV (AS.IV), a novel saponin isolated from the roots of Astragalus membranaceus, has demonstrated antifibrotic and ER stress lowering effects in various tissues during disease conditions. However, the effect of AS.IV on glaucomatous TM fibrosis, ER stress and ocular hypertension has not been studied. Primary human TM cells treated with AS.IV decreased TGFβ2 induced ECM (FN, Col-I) deposition and ER stress (KDEL, ATF4 and CHOP). Moreover, AS.IV treatment reduced TGFβ2 induced NF-κB activation and αSMA expression in TM cells. We found that AS.IV treatment significantly increased levels of matrix metalloproteases (MMP9 and MMP2) and MMP2 enzymatic activity, indicating that the antifibrotic effects of AS.IV are mediated via inhibition of NF-κB and activation of MMPs. AS.IV treatment also reduced ER stress in TM3 cells stably expressing mutant myocilin. Interestingly, the topical ocular AS.IV eye drops (1 mM) significantly decreased TGFβ2 induced ocular hypertension in mice, and this was associated with a decrease in FN, Col-1 (ECM), KDEL (ER stress) and αSMA in mouse TM tissues. Taken together, the results suggest that AS.IV prevents TGFβ2 induced ocular hypertension by modulating ECM deposition and ER stress in the TM.     

低温等离子体引发丙烯酸在PET纳米纤维膜上的接枝聚合

介绍了低温等离子体引发丙烯酸（AA）表面接枝聚合对聚苯二甲酸乙二醇酯（PET）纳米纤维薄膜的改性研究。实验探索了放电时间和放电功率对薄膜润湿性的影响,在真空度60 Pa、AA气体流量3 L/min条件下,放电功率75～150 W范围内,放电时间60 s和放电功率150 W、放电时间30~60 s范围内,处理后薄膜的水接触角均为0°,结果说明了此改性PET纳米纤维膜具有超亲水性。通过扫描电镜、红外和力学性能等测试讨论了接枝处理前后薄膜的形态及性能的变化。实验结果表明气相低温等离子体接枝处理后,薄膜的断裂伸长率和断裂强度有一定的增强。低温等离子体引发AA表面接枝PET纳米纤维薄膜的方法有望成为电纺PET纤维膜表面改性的有效手段,具有积极的应用价值。     

Ar等离子体对聚醚砜膜表面改性的研究

利用Ar等离子体对聚醚砜膜表面的改性研究其亲水性以及污染率的变化,分别讨论了等离子体功率,等离子处理时间,等离子的流量等因素对改性结果的影响.实验结果表明,随着等离子体功率,处理时间以及流量的增加,聚醚砜膜的亲水性不断增强然后基本不再变化.当等离子体功率为60 W,流量为20 sccm,处理时间为120 s时,获得较优的改性效果.此时聚醚砜膜的接触角由60°减小到10°,亲水性明显增强.污染率由0.652变为0.152,抗污染性能得以提高.     

碱性电池隔膜用丙纶非织造布的等离子体改性

利用低温等离子体技术对碱性电池隔膜用丙纶非织造布进行表面改性处理,探讨了影响电池隔膜性能的因素,利用红外光谱、扫描电镜对材料表面性能进行了表征分析。结果表明,不同气体的等离子体对丙纶非织造布进行表面处理的最佳工作参数放电气体、放电功率、放电时间、工作压强分别为:氩气,70 W,3 min,15 Pa;氧气,120 W,3 min,30 Pa;空气,100 W,3 min,50 Pa。通过等离子体表面活化处理,在丙纶表面引入了亲水性基团,同时产生了刻蚀,丙纶非织造布的吸碱速率可提高至每10 min 8 cm左右,吸碱率提高至250%,面电阻大幅降低至8 Ω/cm2左右。     

Surface modification of a polyurethane film by low pressure glow discharge oxygen plasma treatment

Low pressure oxygen plasma has been used to improve the surface wettability of a polyurethane film. The modifications induced by the plasma treatment in the material were analyzed using contact angle measurements. X‐ray photoelectron spectroscopy technique was used for surface characterization of the plasma‐treated films. Atomic force microscopy and scanning electron microscopy were used to analyze topography changes due to the plasma‐etching mechanism. The results show a much better surface wettability of the film even for short exposure times, with a considerable increase in the surface energy values. As expected, functionalization with oxygen plasma is mainly because of surface oxidation with species like (C? O, C?O, OH, etc). An aging process with regard to polar groups rearrangement has been observed, thus promoting a partial hydrophobic recovery. Besides functionalization, the surface wettability of the material improves as a consequence of a slight increase in surface roughness because of the etching effect of oxygen plasma. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Comparison of fibroblast and nerve cells response on plasma treated poly (L‐lactide) surface

Plasma technique can easily be used to introduce desired functional groups or chains onto the surface of materials, and so it has a special application to improve the cell affinity of polymers surfaces. The purpose of this study is to elucidate the interaction between the cells and the surface of crystalline poly (L ‐lactide) (PLLA) samples, which were modified using a low‐temperature plasma treatment apparatus. The plasma treatments were carried out in the carbon dioxide (CO₂) gas. The results showed that the contact angle of the samples, which was plasma treated in CO₂ gas, decreased compared with that of the untreated samples. The hydrophilicity increased because of the introduction of oxygen‐containing functional groups onto the PLLA surfaces according to the spectroscopy for chemical analysis. High quantities of ? C? O groups, such as hydroxyl and carboxyl could be in corporate into the surface of PLLA. The surface wettability, topography, and chemistry of treated PLLA samples were characterized by contact angle measurement, scanning electron microscope (SEM), and ATR‐FTIR spectroscopy. The origin and plasma‐treated samples were used to investigate the interaction of two different types of cells namely, B65 glial nervous, and L929 fibroblast cells. The nervous cell response on the PLLA plasma treated in the CO₂ gas were significantly superior to that of the L929 fibroblast cells and untreated one. The surface modification technique used in this study may be applicable to tissue engineering for the improvement of nerve tissue compatibility of polymer and scaffold‐type substrates. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Ultrasonic cleaning of SBR rubber to improve the performance of subsequent plasma torch treatment

Paraffin wax and other moieties in sulfur vulcanized styrene-butadiene rubber formulations may migrate to the surface, reducing the adhesive strength in joints produced with polyurethane adhesive. In this study, with the aim to remove paraffin wax and other anti-adhesion moieties on the rubber surface to improve adhesion, prior to plasma torch treatment, a methyl ethyl ketone (MEK) cleaning in an ultrasonic bath has been carried out. The surface modifications produced on the rubber surface have been analyzed by contact angle measurements, ATR-IR spectroscopy, XPS and SEM. The adhesion properties have been evaluated by T-peel strength of treated rubber/polyurethane adhesive joints. Ultrasonic cleaning in MEK resulted in partial removal of paraffin wax on the rubber surface and, thus, lower contact angle values, decreased relative intensity of the infrared bands due to hydrocarbon moieties and lower percentage of carbon assessed from XPS spectroscopy were obtained. The ultrasonic cleaning in MEK of the rubber increased the effectiveness of the atmospheric pressure plasma torch treatment, and surface oxidation was produced. However, the oxidation degree decreased with time after plasma torch treatment, likely due to ageing of the surface treated rubber.     

Nonsolvent quantitation of anionic surfactants and inorganic ingredients in laundry detergent products

This paper reports the development of a method for measuring alkylbenzene sulfonates and alkyl sulfates (AS) without requiring the use of chlorinated organic solvents, such as chloroform. Alkylbenzene sulfonates and AS are precipitated with calcium and then isolated by filtration. Through this filtration process, they are separated from inorganic sulfur compounds. After the precipitate is prepared, the level of sulfur is measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) to determine the total anionic surfactant level. Separately, AS are hydrolyzed in an autoclave, and the level of alkylbenzene sulfonates is then measured in the same manner. By using the autoclave, a safe and rapid hydrolysis step has been achieved. In addition to alkylbenzene sulfonates and AS, phosphate, silicate, sulfate, and zeolite can be determined with this sample preparation. This sample preparation procedure was investigated by ICP-AES and was confirmed applicable for simultaneous measurements of alkylbenzene sulfonates, AS, phosphate, silicate, sulfate, and zeolite without using organic solvents. Relative standard deviation for the analysis is less than 1.7%, recovery is more than 99.0%, and the calibration curve gives a correlation coefficient of R=1.000. The detection limit of this method for alkylbenzene sulfonates and AS is 0.6%, for zeolite, 0.04%, for phosphate, 0.4%, for silicate, 0.1%, and for sulfate, 0.2%, by weight in product. This method is applicable to various laundry detergent products that contain the materials mentioned above and is 10 times faster than the six wet chemical methods normally used to analyze these compounds.     

低温等离子体处理对高强聚乙烯纤维表面影响的研究

采用空气低温等离子体处理高强聚乙烯纤维,测试处理前后纤维表面摩擦系数的变化,并采用电子扫描显微镜（SEM）和原子力显微镜（AFM）对纤维表面形貌进行观察分析。结果发现,空气低温等离子体处理的刻蚀作用会在纤维表面形成致密的＂小坑群＂,使得纤维表面产生剥落、联结,造成纤维表面的粗糙程度有所增加,其处理后的纤维表面静、动摩擦系数有所提高。     

Random and aligned PLLA : PRGF electrospun scaffolds for regenerative medicine

Random and aligned electrospun scaffolds were prepared combining poly(l ‐lactic acid) (PLLA) and activated platelet‐rich plasma (PRGF) at various proportions, with the aim of elucidating the role of nanofibers orientation and growth factors on cell attachment and proliferation. PRGF is released from scaffolds in a sustained way for at least 3 weeks, without an initial burst effect. Mesenchymal stem cells (MSCs) seeded on the random scaffolds present a polygonal and random orientation in any direction of the scaffold. On the other hand, aligned scaffolds are able to promote cell attachment and proliferation in the direction of the nanofibers. The incorporation of PRGF in the scaffolds enhances cell proliferation for at least 2 weeks. Overall, aligned electrospun PLLA : PRGF scaffolds can encapsulate growth factors at relatively large proportions and sustain their release to enhance cell attachment and proliferation as well as eliciting cell alignment. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41372.