scholarly journals Functionalized Non-vascular Nitinol Stent via Electropolymerized Polydopamine Thin Film Coating Loaded with Bortezomib Adjunct to Hyperthermia Therapy

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Ludwig Erik Aguilar ◽  
Batgerel Tumurbaatar ◽  
Amin Ghavaminejad ◽  
Chan Hee Park ◽  
Cheol Sang Kim
Keyword(s):  
Film Coating ◽  
Potential Method ◽  
Dependent Manner ◽  
Gastrointestinal Malignancies ◽  
Nitinol Stent ◽  
Combined Application ◽  
Hyperthermia Therapy ◽  
Nitinol Stents ◽  
Release Studies ◽  
Ft Ir

Abstract Gastrointestinal malignancies have been a tremendous problem in the medical field and cover a wide variety of parts of the system, (i.e. esophagus, duodenum, intestines, and rectum). Usually, these malignancies are treated with palliation with the use of non-vascular nitinol stents. However, stenting is not a perfect solution for these problems. While it can enhance the quality of life of the patient, in time the device will encounter problems such as re-occlusion due to the rapid growth of the tumor. In this study, we propose a functionalization technique using electropolymerization of polydopamine directly onto the nitinol stent struts for the combined application of hyperthermia and chemotherapy. The coating was characterized using FESEM, XPS, and FT-IR. Drug release studies show that facile release of the anticancer drug BTZ from the surface of the polydopamine-coated stent could be achieved by the dissociation between catechol groups of polydopamine and the boronic acid functionality of BTZ in a pH-dependent manner. The anti-cancer property was also evaluated, and cytotoxicity on ESO26 and SNU-5 cancer cell lines were observed. Our results suggest that the introduced approach can be considered as a potential method for therapeutic stent application.

Crush implantation of a self-expanding interwoven stent over a subintimally recanalized standard stent in a TASC D lesion of the superficial femoral artery

VASA ◽  
2012 ◽  
Vol 41 (6) ◽  
pp. 458-462 ◽  
Author(s):  
Vogel ◽  
Strothmeyer ◽  
Cebola ◽  
A. Katus ◽  
Blessing
Keyword(s):  
Femoral Artery ◽  
Superficial Femoral Artery ◽  
Popliteal Artery ◽  
Duplex Ultrasound ◽  
Stent Fracture ◽  
Nitinol Stent ◽  
Nitinol Stents ◽  
Walking Capacity ◽  
Radial Strength ◽  
Good Treatment Option

We demonstrate feasibility of implantation of a self-expanding interwoven nitinol stent in a claudicant, where recanalization attempt of a heavily calcified, occluded superficial femoral artery (TASC D lesion) was complicated by a previously implanted, fractured standard stent. Wire passage through the occlusion and beyond the fractured stent could only be achieved through the subintimal space. A dedicated reentry device was used to allow distal wire entry into the true lumen at the level of the popliteal artery. Despite crushing of the fractured stent with a series of increasingly sized standard balloons, a significant recoil remainded in the area of the crushed stent. To secure patency of the femoro-popliteal artery we therefore decided to implant the novel self-expanding interwoven nitinol stent (Supera Veritas (TM), IDEV), whose unique feature is an exceptional high radial strength. Patient presented asymptomatic without any impairment of his walking capacity at three month follow up and duplex ultrasound confirmed patency of the stent. Subintimal recanalizations can be complicated by previously implanted stents, in particular in the presence of stent fracture, where intraluminal wire passage often can not be achieved. Considering the high radial strength and fracture resistance, interwoven nitinol stents represent a good treatment option in those challenging cases and they can be used to crush standard nitinol and ballonexpandable stents.

Clinical Experience with a New Nitinol Self-Expanding Stent in Peripheral Arteries

1996 ◽  
Vol 3 (4) ◽  
pp. 369-379 ◽  
Author(s):  
Michel Henry ◽  
Max Amor ◽  
Rafael Beyar ◽  
Isabelle Henry ◽  
Jean-Marc Porte ◽  
...  
Keyword(s):  
Long Term Results ◽  
Lesion Length ◽  
Secondary Patency ◽  
Peripheral Arteries ◽  
External Compression ◽  
Nitinol Stent ◽  
Nitinol Stents ◽  
The Mean

Purpose: To evaluate a new self-expanding nitinol coil stent in stenotic or occluded peripheral arteries. Methods: Seventy-three symptomatic patients (58 men; mean age 67 years) were treated with nitinol stents for lesions in the iliac artery (9 stenoses); superficial femoral artery (SFA) (39 stenoses, 6 occlusions); popliteal artery and tibioperoneal trunk (9 stenoses, 7 occlusions); and 3 bypass grafts. Mean diameter stenosis was 84.4% ± 9.9% (range 75% to 100%), and mean lesion length was 45 ± 23 mm (range 20 to 120 mm). Results: Eighty-eight 40-mm-long stents with diameters between 5 and 8 mm were implanted percutaneously for suboptimal dilation (n = 45); dissection (n = 21); and restenosis (n = 7). All stents but one were implanted successfully; the malpositioned stent was removed, and another stent was successfully deployed. There were 3 (4.1%) failures due to thrombosis at 24 hours. During the mean 16-month follow-up (range to 44 months), 4 restenoses (3 femoral, 1 popliteal) have occurred; 2 were treated with repeat dilation and 2 underwent bypass. Primary and secondary patency rates at 18 months were 87% and 90%, respectively, for all lesions (iliac: 100% for both; femoral: 85% and 88%; popliteal: 87% and 100%). Conclusions: This new nitinol stent seems to be safe and effective with favorable long-term results, even in distal SFA lesions and popliteal arteries. Its flexibility and resistance to external compression allow its placement in tortuous arteries and near joints.

scholarly journals Insulin forms amyloid in a strain-dependent manner: An FT-IR spectroscopic study

2004 ◽  
Vol 13 (7) ◽  
pp. 1927-1932 ◽  
Author(s):  
Wojciech Dzwolak ◽  
Vytautas Smirnovas ◽  
Ralf Jansen ◽  
Roland Winter
Keyword(s):  
Spectroscopic Study ◽  
Dependent Manner ◽  
Ft Ir ◽  
Ir Spectroscopic ◽  
Strain Dependent

scholarly journals Formulation and characterization of flurbiprofen loaded microsponge based gel for sustained drug delivery

2019 ◽  
Vol 10 (4) ◽  
pp. 2765-2776
Author(s):  
Naresh Kshirasagar ◽  
Goverdhan Puchchakayala ◽  
Balamurgan K
Keyword(s):  
Drug Delivery ◽  
Particle Size ◽  
Drug Release ◽  
Diffusion Method ◽  
Skin Delivery ◽  
Sustained Action ◽  
Release Studies ◽  
Ft Ir ◽  
Polymer Ratio

The new investigation in this present work is to develop microsponges constructed novel drug delivery system for sustained action of Flurbiprofen. Quai-emulsion solvent diffusion method was engaged using Ethyl cellulose and Eudragit RS100 with drug: polymer ratio for development of microsponges. For optimization purposes, several factors are considered in the investigation. Several evaluation studies for the formed microsponges were carried out FT-IR, SEM, DSC, X-RD, particle size analysis, morphology, drug loading and In vitro drug release studies were carried out. Finally, it was concluded that there is no drug-polymer interaction as per DSC & FT-IR. Encapsulation efficiency, particle size and drug content showed a higher impact on alteration of drug-polymer ratio. SEM studies showed that morphological microsponges are spherical and porous in nature and with the mean particle size of 38.86 μm. The gel loaded with microsponges, were followed by In vitro and Ex vivo drug release studies by modified Franz diffusion cell. Skin delivery of optimized formulation enhanced the drug residence time and maintained therapeutic concentration for an extended period of time, which is possible to show sustained action of the drug.

scholarly journals Simonkolleite Coating on Poly(Amino Acids) to Improve Osteogenesis and Suppress Osteoclast Formation in Vitro

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1505 ◽  
Author(s):  
Shuyang Li ◽  
Xingtao Chen ◽  
Xiaomei Wang ◽  
Yi Xiong ◽  
Yonggang Yan ◽  
...  
Keyword(s):  
Amino Acids ◽  
Osteoclast Formation ◽  
Mouse Bone Marrow ◽  
Graft Material ◽  
Dependent Manner ◽  
E Coli ◽  
Ft Ir ◽  
Dose Dependent ◽  
Relative Cell Viability

Zinc can enhance osteoblastic bone formation and stimulate osteogenic differentiation, suppress the differentiation of osteoclast precursor cells into osteoclasts, and inhibit pathogenic bacterial growth in a dose-dependent manner. In this study, simonkolleite, as a novel zinc resource, was coated on poly (amino acids) (PAA) via suspending PAA powder in different concentrations of zinc chloride (ZnCl2) solution, and the simonkolleite-coated PAA (Zn–PAA) was characterized by SEM, XRD, FT-IR and XPS. Zinc ions were continuously released from the coating, and the release behavior was dependent on both the concentration of the ZnCl2 immersing solution and the type of soak solutions (SBF, PBS and DMEM). The Zn–PAA was cultured with mouse bone marrow stem cells (BMSCs) through TranswellTM plates, and the results indicated that the relative cell viability, alkaline phosphatase (ALP) activity and mineralization of BMSCs were significantly higher with Zn–PAA as compared to PAA. Moreover, the Zn–PAA was cultured with RAW264.7 cells, and the results suggested an inhibiting effect of Zn–PAA on the cell differentiation into osteoclasts. In addition, Zn–PAA exhibited an antibacterial activity against both S. aureus and E. coli. These findings suggest that simonkolleite coating with certain contents could promote osteogenesis, suppress osteoclast formation and inhibit bacteria, indicating a novel way of enhancing the functionality of synthetic bone graft material and identifying the underline principles for designing zinc-containing bone grafts.

Quantification of surface functional groups on silica nanoparticles: comparison of thermogravimetric analysis and quantitative NMR

The Analyst ◽  
2019 ◽  
Vol 144 (18) ◽  
pp. 5589-5599 ◽  
Author(s):  
Filip Kunc ◽  
Vinod Balhara ◽  
Ying Sun ◽  
Malgosia Daroszewska ◽  
Zygmunt J. Jakubek ◽  
...  
Keyword(s):  
Thermogravimetric Analysis ◽  
Silica Nanoparticles ◽  
Functional Group ◽  
Evolved Gas Analysis ◽  
Potential Method ◽  
Gas Analysis ◽  
Evolved Gas ◽  
Ft Ir ◽  
Modified Silica Nanoparticles ◽  
Surface Modified

Thermogravimetric analysis (TGA) coupled with evolved gas analysis-FT-IR has been examined as a potential method to study the functional group content for surface modified silica nanoparticles.

Baicalein Synergy Lenalidomide To Induce Apoptosis Of Myeloma Cell

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 5328-5328
Author(s):  
Ruibo Zhang ◽  
Zi Ma ◽  
Shangqin Liu ◽  
Li He ◽  
Chaoping Xu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Protein Expression ◽  
Apoptotic Cell ◽  
Time Dependent ◽  
Dependent Manner ◽  
Rt Pcr ◽  
P Values ◽  
Combined Application ◽  
Gene And Protein Expression ◽  
Rpmi 8226

Abstract Objective To understand the apoptotic effects and cereblon (CRBN) gene and protein expression induced by baicalein in MM cells. Methods Apoptotic MM cells induced baicalein，lenalidomide or combination of BAI and lenalidomide were stained by using Annexin-V and analyzed by flow cytometry. RT-PCR was used to detect CRBN gene expression in MM cells. CRBN protein expression was detected by western blot in MM cell lines. Results At the concentration of 40 μmol/L, baicalein can induce apoptosis of U266 cells in a time-dependent manner. At the different BAI treated time points (24h, 48h, 72h), the apoptotic cell percentages were 6.11%, 11.9%, 16.7%; After treated RPMI 8226 cells for 72 hours, combined application of baicalein and lenalidomide (both concentrations are 40 μmol/L) could induce more cell apoptosis than baicalein or lenalidomide alone. The apoptotic cell percentages induced by baicalein, lenalidomide or combined application of baicalein and lenalidomide were 15.9%, 4.27%, and 57.5%. CRBN gene expression detected by RT-PCR could be induced by baicalein in U266 cells in a dose-and time-dependent manner. Treated U266 cells for 24h at concentrations of 10 μmol/L, 20 μmol/L and 40 μmol/L, baicalein upregulated CRBN gene expression times were 2.246 ± 0.068, 2.399 ± 0.178 and 3.591 ± 0.061,respectively，compared to the control group. Statistically, the P values were 0.003, 0.009 and 0.001; Treated U266 cells at concentrations of 40 μmol/L at different time points (6h, 12h and 24h), baicalein upregulated CRBN gene expression times were 2.372 ± 0.079, 2.494 ± 0.189 and 3.228 ± 0.151, its P values were 0.002, 0.008 and 0.002.CRBN protein expression detected by using western blot could be induced by baicalein in both U266 and RPMI8226 cell lines. Conclusions Baicalein at suitable concentrations induced MM cells apoptosis in a time-dependent manner. Comparison with the single component used alone,combined application of baicalein and lenalidomide exhibited stronger inhibition effect on proliferation of RPMI 8226. Considering CRBN is the cellular target for lenalidomide, baicalein can up-regulate the CRBN gene and protein expression in MM cells and may enhance MM cell sensitivity to apoptotic stimuli. Therefore, baicalein up-regulated CRBN gene and protein expression and sensitized MM cells to apoptosis stimuli induced by lenalidomide. It provides us a possibility for baicalein clinical application to overcome the resistance to lenalidomide for MM patients in the future Disclosures: No relevant conflicts of interest to declare.

scholarly journals Topical Chitosan-Based Thermo-Responsive Scaffold Provides Dexketoprofen Trometamol Controlled Release for 24 h Use

Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2100
Author(s):  
Luis Castillo-Henríquez ◽  
Pablo Sanabria-Espinoza ◽  
Brayan Murillo-Castillo ◽  
Gabriela Montes de Oca-Vásquez ◽  
Diego Batista-Menezes ◽  
...  
Keyword(s):  
Controlled Release ◽  
Kinetic Models ◽  
In Vitro Release ◽  
Solution Temperature ◽  
Burst Release ◽  
Release Studies ◽  
Dexketoprofen Trometamol ◽  
Ft Ir ◽  
Healing Wounds

Chronic and non-healing wounds demand personalized and more effective therapies for treating complications and improving patient compliance. Concerning that, this work aims to develop a suitable chitosan-based thermo-responsive scaffold to provide 24 h controlled release of Dexketoprofen trometamol (DKT). Three formulation prototypes were developed using chitosan (F1), 2:1 chitosan: PVA (F2), and 1:1 chitosan:gelatin (F3). Compatibility tests were done by DSC, TG, and FT-IR. SEM was employed to examine the morphology of the surface and inner layers from the scaffolds. In vitro release studies were performed at 32 °C and 38 °C, and the profiles were later adjusted to different kinetic models for the best formulation. F3 showed the most controlled release of DKT at 32 °C for 24 h (77.75 ± 2.72%) and reduced the burst release in the initial 6 h (40.18 ± 1.00%). The formulation exhibited a lower critical solution temperature (LCST) at 34.96 °C, and due to this phase transition, an increased release was observed at 38 °C (88.52 ± 2.07% at 12 h). The release profile for this formulation fits with Hixson–Crowell and Korsmeyer–Peppas kinetic models at both temperatures. Therefore, the developed scaffold for DKT delivery performs adequate controlled release, thereby; it can potentially overcome adherence issues and complications in wound healing applications.

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