scholarly journals Bioactive Magnetoelastic Materials as Coatings for Implantable Biomaterials

2009 ◽  
Vol 3 (2) ◽  
Author(s):  
E. Vlaisavljevich ◽  
L. Janka ◽  
K. Ong ◽  
R. Rajachar
Keyword(s):  
Cell Adhesion ◽  
Soft Tissue ◽  
Cell Viability ◽  
Control Cell ◽  
Fibrous Tissue ◽  
Fluorescent Imaging ◽  
Biomedical Implants ◽  
Stability Function ◽  
Tissue Interface ◽  
The Stability

Enhanced fibroblast activity at the soft tissue-implant interface can dramatically decrease the stability, function, and lifespan of biomedical implants such as bone anchored prostheses. Although bone anchoring systems dramatically improve prosthetic limb mechanical stability, uncontrolled fibrosis at the soft tissue-mounting post interface is a significant problem. The aberrant cell growth leads to irregular skin folds that prevent proper sealing to the bone anchoring post and also serves as a site for opportunistic infection and failure of the prosthetic system. We are developing a bioactive vibrational coating to control fibrous tissue overgrowth. The coating is based on a magnetoelastic (ME) material that can be set to vibrate at a predetermined amplitude and frequency using a controlled magnetic field. We hypothesize that small local vibrations can be used to selectively control cell adhesion and gene expression to promote and maintain functional stability at the implant-tissue interface. For bone anchored prostheses, the ME coating would be applied around the mounting post at the soft tissue interface. The specific aims of this work were to (1) modify the coating for use in contact with a biologic environment and (2) determine if local vibrational strain can efficiently control cell attachment to the coating without significantly influencing viability. First, two common biocompatible polymers, polyurethane and chitosan, were deposited as thin films on the ME coating to allow for its use in tissue culture. An indirect cytotoxicity test was used to determine fibroblast (L929) viability in media conditioned for 24 and 48 hours with uncoated, chitosan coated, and polyurethane coated ME materials. Results demonstrated that both polymer coatings returned cell survival to levels statistically indistinguishable from controls (cells cultured on tissue cultured polystyrene, TCP) with cell viability over 96% under all coating conditions. Second, the affect of local vibrations on cell adhesion was tested in vitro. A cell viability assay (Calcein-AM) followed by fluorescent imaging was used to quantify attachment and viability of fibroblasts cultured directly on the bioactive ME material. Results clearly indicated that controlled local vibrations can induce complete cell detachment from the ME material compared with non-vibrated controls at up to 72 hours post-seeding. Further, cells detached via applied vibrations showed no significant decrease in viability compared to adherent controls. These results suggest the potential for this novel coating to effectively control fibrous tissue overgrowth using the mild application of tunable local vibrations, a significant and cost-effective approach that could improve the stability, function, and lifespan of biomedical implants and reduce the need for surgical revision.

scholarly journals MiR-140-3p inhibits the cell viability and promotes apoptosis of synovial fibroblasts in rheumatoid arthritis through targeting sirtuin 3

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Beibei Zu ◽  
Lin Liu ◽  
Jingya Wang ◽  
Meirong Li ◽  
Junxia Yang
Keyword(s):  
Rheumatoid Arthritis ◽  
Cell Viability ◽  
Cell Apoptosis ◽  
Caspase 3 ◽  
Pearson Correlation ◽  
Fibrous Tissue ◽  
Synovial Fibroblasts ◽  
Cell Counting ◽  
Sirtuin 3 ◽  
Fibrous Tissues

Abstract Background Synovial fibroblasts (SFs) with the abnormal expressions of miRNAs are the key regulator in rheumatoid arthritis (RA). Low-expressed miR-140-3p was found in RA tissues. Therefore, we attempted to investigate the effect of miR-140-3p on SFs of RA. Methods RA and normal synovial fibrous tissue were gathered. The targets of miR-140-3p were found by bioinformatics and luciferase analysis. Correlation between the expressions of miR-140-3p with sirtuin 3 (SIRT3) was analyzed by Pearson correlation analysis. After transfection, cell viability and apoptosis were detected by cell counting kit-8 and flow cytometry. The expressions of miR-140-3p, SIRT3, Ki67, Bcl-2, Bax, and cleaved Caspase-3 were detected by RT-qPCR or western blot. Results Low expression of miR-140-3p and high expression of SIRT3 were found in RA synovial fibrous tissues. SIRT3 was a target of miR-140-3p. SIRT3 expression was negatively correlated to the expression of miR-140-3p. MiR-140-3p mimic inhibited the MH7A cell viability and the expressions of SIRT3, Ki67, and Bcl-2 and promoted the cell apoptosis and the expressions of Bax and cleaved Caspase-3; miR-140-3p inhibitor showed an opposite effect to miR-140-3p mimic on MH7A cells. SIRT3 overexpression not only promoted the cell viability and inhibited cell apoptosis of MH7A cells but also reversed the effect of miR-140-3p mimic had on MH7A cells. Conclusions The results in this study revealed that miR-140-3p could inhibit cell viability and promote apoptosis of SFs in RA through targeting SIRT3.

MASTER STABILITY FUNCTIONS FOR SYNCHRONIZED COUPLED SYSTEMS

1999 ◽  
Vol 09 (12) ◽  
pp. 2315-2320 ◽  
Author(s):  
LOUIS M. PECORA ◽  
THOMAS L. CARROLL
Keyword(s):  
Simple Form ◽  
Coupled Systems ◽  
Stability Function ◽  
Coupled Oscillator ◽  
Synchronous State ◽  
Master Stability Function ◽  
Stability Functions ◽  
The Stability

We show that many coupled oscillator array configurations considered in the literature can be put into a simple form so that determining the stability of the synchronous state can be done by a master stability function which solves, once and for all, the problem of synchronous stability for many couplings of that oscillator.

scholarly journals Evaluation of the Bone-ligament and tendon insertions based on Raman spectrum and its PCA and CLS analysis

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Yang Wu ◽  
Yu Dong ◽  
Jia Jiang ◽  
Haiqing Li ◽  
Tongming Zhu ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Cruciate Ligament ◽  
Physically Active ◽  
Mapping Procedure ◽  
Raman Spectroscopic ◽  
Co Morbidity ◽  
Tissue Interface ◽  
Anterior Cruciate ◽  
Raman Spectral ◽  
Artificial Prosthesis

Abstract Injuries to the Anterior Cruciate Ligament (ACL) and Rotator Cuff Tendon (RCT) are common in physically active and elderly individuals. The development of an artificial prosthesis for reconstruction/repair of ACL and RCT injuries is of increasing interest due to the need for viable tissue and reduced surgically-related co-morbidity. An optimal prosthesis design is still elusive, therefore an improved understanding of the bone-soft tissue interface is extremely urgent. In this work, Raman spectral mapping was used to analyze, at the micron level, the chemical composition and corresponding structure of the bone-soft tissue interface. Raman spectroscopic mapping was performed using a Raman spectrometer with a 785 nm laser coupled to a microscope. Line-mapping procedure was performed on the ACL and RCT bone insertion sites. The classical least squares (CLS) fitting model was created from reference spectra derived from pure bone and soft-tissue components, and spectral maps collected at multiple sites from ACL and RCT specimens. The results suggest that different source of interface shows different boundary, even they seems have the same components. Compared to the common histology results, it provided intact molecular information that can easily distinguished some relative component change.

scholarly journals Porous Cellulose-Collagen Scaffolds For Soft Tissue Regeneration: Influence of Cellulose Derivatives On Mechanical Properties And Compatibility With Adipose-Derived Stem Cells.

2022 ◽  
Author(s):  
Katarína Kacvinská ◽  
Martina Trávničková ◽  
Lucy Vojtová ◽  
Petr Poláček ◽  
Jana Dorazilová ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Stem Cells ◽  
Cell Adhesion ◽  
Soft Tissue ◽  
Vascular Tissue ◽  
Biological Properties ◽  
Cellulose Derivatives ◽  
Adipose Derived Stem Cells ◽  
Soft Tissue Regeneration

Abstract This study deals with cellulose derivatives in relation to the collagen fibrils in composite collagen-cellulose scaffolds for soft tissue engineering. Two types of cellulose, i.e., oxidized cellulose (OC) and carboxymethyl cellulose (CMC), were blended with collagen (Col) to enhance its elasticity, stability and sorptive biological properties, e.g. hemostatic and antibacterial features. The addition of OC supported the resistivity of the Col fibrils in a dry environment, while in a moist environment OC caused a radical drop. The addition of CMC reduced the mechanical strength of the Col fibrils in both environments. The elongation of the Col fibrils was increased by both types of cellulose derivatives in both environments, which is closely related to tissue like behaviour. In these various mechanical environments, the ability of human adipose-derived stem cells (hADSCs) to adhere and proliferate was significantly greater in the Col and Col/OC scaffolds than in the Col/CMC scaffold. This is explained by deficient mechanical support and loss of stiffness due to the high swelling capacity of CMC. Although Col/OC and Col/CMC acted differently in terms of mechanical properties, both materials were observed to be cytocompatible, with varying degrees of further support for cell adhesion and proliferation. While Col/OC can serve as a scaffolding material for vascular tissue engineering and for skin tissue engineering, Col/CMC seems to be more suitable for moist wound healing, e.g. as a mucoadhesive gel for exudate removal, since there was almost no cell adhesion.

Development of Polymer/Nanodiamond Composite Coatings to Control Cell Adhesion, Growth, and Functions

2015 ◽  
pp. 1-26 ◽  
Author(s):  
Milena Keremidarska ◽  
Kamelia Hristova ◽  
Todor Hikov ◽  
Ekaterina Radeva ◽  
Dimitar Mitev ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Composite Coatings ◽  
Control Cell

Esthetic And Functional Integration Of Soft Tissue Around Dental Implants: Thickness, Width, Stability.

2021 ◽  
Author(s):  
Aleksandr Lysov ◽  
Andre Saadoun
Keyword(s):  
Soft Tissue ◽  
Functional Integration ◽  
Daily Practice ◽  
Clinical Approach ◽  
Soft Tissue Management ◽  
Mucosal Thickness ◽  
Biological Protection ◽  
The Stability ◽  
Implant Treatment

The long-term Functional success of the implant treatment depends on the stability of the crestal bone tissue around the implant platform. The Esthetic result is achieved by an adequate soft tissue in the peri-implant zone. Furthermore, the soft tissue creates the buffer area that ensures the mechanical and biological protection of the underlying bone. Therefore, it is necessary to maintain for a long term, not only the implant osseointegration but also the integration of the soft tissue around the Sub and Supra-structure of the restoration. In order to create the protective soft tissue area, it is necessary to ensure three criteria. This treatment approach will be defined as the TWS – Soft Tissue Management : T for Thickness , W for Width, and S for Stability . The purpose of this article is to present with clinical cases, the detailed description of each criteria. There are many ways to achieve the two first criteria and they are well described in the literature. Achieving the third criteria of the Stability become possible only in the last years since the development of the digital technology and its implementation into the dental practice. A one time abutment and the creation of peri- implant mucosal thickness with an optimal amount of the attached keratinized gingiva above and around the implant platform, for muco-gingival integration of the system, are therefore a prerequisite for functional and esthetic result. The article presents the possibility for the clinicians to use in their daily practice this new clinical approach of TWS - Soft Tissue Management.

Sarcomas of Soft Tissue and Bone

2011 ◽  
Author(s):  
Adam Lerner ◽  
Huihong Xu ◽  
Karen H Antman
Keyword(s):  
Soft Tissue ◽  
Meta Analysis ◽  
Survival Rates ◽  
Fibrous Tissue ◽  
Soft Tissue Sarcomas ◽  
Kaposi Sarcoma ◽  
Uterine Leiomyosarcoma ◽  
Increased Risk ◽  
Bone Sarcomas ◽  
Epidemiologic Features

Sarcomas originate from bone or soft tissue. The most common bone sarcomas are osteosarcomas, Ewing sarcomas, and chondrosarcomas. Soft tissue sarcomas develop in fibrous tissue, fat, muscle, blood vessels, and nerves. Historically, soft tissue sarcomas of the trunk and extremities were reported separately from those of visceral organs (e.g., gastrointestinal and gynecologic sarcomas). This chapter discusses the classification, epidemiology, diagnosis, staging, and treatment of sarcomas of bone and cartilage, and classic soft tissue sarcomas. Management of Kaposi sarcoma, gastrointestinal stromal tumors (GISTs), mesothelioma, and rhabdomyosarcoma is also described. Figures include images of patients with osteosarcoma, liposarcoma, uterine leiomyosarcoma, GIST, and osteosarcoma in a patient with Paget disease of bone. Tables list epidemiologic features of sarcomas, a summary of sarcomas by histology, familial syndromes associated with increased risk of sarcoma, survival rates in sarcoma patients, staging of soft tissue sarcomas, and results of a meta-analysis of doxorubicin-based adjuvant chemotherapy for localized resectable soft tissue sarcoma. This chapter contains 126 references.

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