• Journal of Periodontal and Implant Science
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• v.46 no.6
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• pp.362-371
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• 2016

Purpose: The increasing demand for esthetically pleasing results has contributed to the use of ceramics for dental implant abutments. The aim of this study was to compare the biological response of epithelial tissue cultivated on lithium disilicate ($LS_2$) and zirconium oxide ($ZrO_2$) ceramics. Understanding the relevant physicochemical and mechanical properties of these ceramics will help identify the optimal material for facilitating gingival wound closure. Methods: Both biomaterials were prepared with 2 different surface treatments: raw and polished. Their physicochemical characteristics were analyzed by contact angle measurements, scanning white-light interferometry, and scanning electron microscopy. An organotypic culture was then performed using a chicken epithelium model to simulate peri-implant soft tissue. We measured the contact angle, hydrophobicity, and roughness of the materials as well as the tissue behavior at their surfaces (cell migration and cell adhesion). Results: The best cell migration was observed on $ZrO_2$ ceramic. Cell adhesion was also drastically lower on the polished $ZrO_2$ ceramic than on both the raw and polished $LS_2$. Evaluating various surface topographies of $LS_2$ showed that increasing surface roughness improved cell adhesion, leading to an increase of up to 13%. Conclusions: Our results demonstrate that a biomaterial, here $LS_2$, can be modified using simple surface changes in order to finely modulate soft tissue adhesion. Strong adhesion at the abutment associated with weak migration assists in gingival wound healing. On the same material, polishing can reduce cell adhesion without drastically modifying cell migration. A comparison of $LS_2$ and $ZrO_2$ ceramic showed that $LS_2$ was more conducive to creating varying tissue reactions. Our results can help dental surgeons to choose, especially for esthetic implant abutments, the most appropriate biomaterial as well as the most appropriate surface treatment to use in accordance with specific clinical dental applications.

• BMB Reports
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• v.50 no.8
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• pp.429-434
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• 2017

Endometriosis is the abnormal growth of endometrial cells outside the uterus, causing pelvic pain and infertility. Furthermore, adhesion of endometrial tissue fragments to pelvic mesothelium is required for the initial step of endometriosis formation outside uterus. $TGF-{\beta}1$ and adhesion molecules importantly function for adhesion of endometrial tissue fragments to mesothelium outside uterus. However, the function of $TGF-{\beta}1$ on the regulation of adhesion molecule expression for adhesion of endometrial tissue fragments to mesothelium has not been fully elucidated. Interestingly, transforming growth factor ${\beta}1$ ($TGF-{\beta}1$) expression was higher in endometriotic epithelial cells than in normal endometrial cells. The adhesion efficiency of endometriotic epithelial cells to mesothelial cells was also higher than that of normal endometrial cells. Moreover, $TGF-{\beta}1$ directly induced the adhesion of endometrial cells to mesothelial cells through the regulation of integrin of ${\alpha}V$, ${\alpha}6$, ${\beta}1$, and ${\beta}4$ via the activation of the $TGF-{\beta}1/TGF-{\beta}RI/Smad2$ signaling pathway. Conversely, the adhesion of $TGF-{\beta}1-stimulated$ endometrial cells to mesothelial cells was clearly reduced following treatment with neutralizing antibodies against specific $TGF-{\beta}1-mediated$ integrins ${\alpha}V$, ${\beta}1$, and ${\beta}4$ on the endometrial cell membrane. Taken together, these results suggest that $TGF-{\beta}1$ may act to promote the initiation of endometriosis by enhancing integrin-mediated cell-cell adhesion.

• Journal of Korean Foot and Ankle Society
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• v.13 no.1
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• pp.7-13
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• 2009

Purpose: The purpose of this study was to evaluate the effect of Sodium hyaluronate-Sodium carboxymethyl cellulose (HA-CMC) on tissue adhesion after tenorrhapy in tenotomized Achilles tendon of the Sprague-Dawley rat. Materials and Methods: Twenty-eight legs of 14 Sprague-Dawley rat were used in study. After tenotomy of the Achilles tendons, tenorrhaphies were performed. Simple tenorrhaphy without any other procedures were performed on the left Achilles tendons (control group), and additional HA-CMC injections were done prior to the tenorrhaphy on the right Achilles tendons (HA-CMC group). Gross and histological examinations were made to identify differences between the two groups, 1, 2, 6, 8, 10, 12 and 14 weeks respectively. Results: Distinct decrease in granulation tissues and adhesions were seen in the HA-CMC group during gross inspection at 6 and 8 week after the operation. On histological analysis of the HA-CMC group, although increased infiltrations of inflammation cells were observed during 1 week, less adhesion were seen at 6, 8 and 10 weeks after the operation. In HA-CMC group, superior healing processes were seen at 6, 8 and 10 weeks and less fibrotic changes, compared to control group, were seen at 2 and 6 weeks. Conclusion: Prevention of adjacent tissue adhesion was made possible through decrease in collagen deposition and fibrosis by injecting HA-CMC before tenorrhaphy of Achilles tendon. Also, histologically faster healing process of the collagen fibers within the Achilles tendon was observed.

• Biomolecules & Therapeutics
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• v.21 no.4
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• pp.277-283
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• 2013

In this study, we investigated the effects of a selective urotensin II (UII) receptor antagonist, SB-657510, on the inflmmatory response induced by UII in human umbilical vein endothelial cells (EA.hy926) and human monocytes (U937). UII induced inflammatory activation of endothelial cells through expression of proinflammatory cytokines (IL-$1{\beta}$ and IL-6), adhesion molecules (VCAM-1), and tissue factor (TF), which facilitates the adhesion of monocytes to EA.hy926 cells. Treatment with SB-657510 significantly inhibited UII-induced expression of IL-$1{\beta}$, IL-6, and VCAM-1 in EA.hy926 cells. Further, SB-657510 dramatically blocked the UII-induced increase in adhesion between U937 and EA.hy926 cells. In addition, SB-657510 remarkably reduced UII-induced expression of TF in EA.hy926 cells. Taken together, our results demonstrate that the UII antagonist SB-657510 decreases the progression of inflammation induced by UII in endothelial cells.

• Carbon letters
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• v.13 no.3
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• pp.139-150
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• 2012

Poly-L-lactic acid (PLLA), PLLA/hydroxyapatite (HA), PLLA/multiwalled carbon nanotubes (MWNTs)/HA, PLLA/trifluoroethanol (TFE), PLLA/gelatin, and carbon nanofibers (CNFs)/${\beta}$-tricalcium phosphate (${\beta}$-TCP) composite membranes (scaffolds) were fabricated by electrospinning and their morphologies, and mechanical properties were characterized for use in bone tissue regeneration/guided tissue regeneration. MWNTs and HA nanoparticles were well distributed in the membranes and the degradation characteristics were improved. PLLA/MWNTs/HA membranes enhanced the adhesion and proliferation of periodontal ligament cells (PDLCs) by 30% and inhibited the adhesion of gingival epithelial cells by 30%. Osteoblast-like MG-63 cells on the randomly fiber oriented PLLA/TEF membrane showed irregular forms, while the cells exhibited shuttle-like shapes on the parallel fiber oriented membrane. Classical supersaturated simulated body fluids were modified by $CO_2$ bubbling and applied to promote the biomineralization of the PLLA/gelatin membrane; this resulted in predictions of bone bonding bioactivity of the substrates. The ${\beta}$-TCP membranes exhibit good biocompatibility, have an effect on PDLC growth comparable to that of pure CNF membrane, and can be applied as scaffolds for bone tissue regeneration.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.203-204
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• 2006

Studies on some biodegradable polymers and other materials such as hydrogels have shown the promising potential for a variety of surgical applications. Postoperative adhesion caused by the natural consequence of surgical wound healing results in problems of the repeated surgery. Recently, scientists have developed absorbable anti-adhesion barriers that can protect a tissue from adhesion in case they are in use; however, they are dissolved when no longer needed. Although these approaches have been attempted to fulfill the criteria for adhesion prevention, none can perfectly prevent adhesions in all situations. Overall of this work, a new method to fabricate an anti-adhesion membrane using biodegradable polymer and hydrogel has been developed. The ideal barrier for preventing postoperative adhesion would have the following properties; it should be (i) resorbable (ii) non-reactive (iii) easy to apply (iv) capable of being fixed in position. In order to fulfill these properties, we adopted solid freeform fabrication method combined with surface modification which includes the hydrogel coating, therefore, inner or outer structure can be controlled and the property of anti adhesion can be improved.

• YAKHAK HOEJI
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• v.53 no.3
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• pp.119-124
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• 2009

Cell-cell adhesion managed by various adhesion molecules plays an important role in regulating functional activation of cells. This event mediates attachment of inflammatory cells to endothelial cells, interaction of antigen-presenting cells with T cells and metastatic adherence of cancer cells to epithelial tissue cells. Therefore, this cellular response is considered as one of therapeutic target to treat various cancers and inflammatory diseases. To develop proper model for evaluation of functional activation of adhesion molecules, the ability of U937 and Jurkat T cells responsive to various adhesion inducers such as phorbal-12-myristate-13-acetate (PMA), staurosporin and monoclonal antibodies to CD29, CD43 and CD98 was investigated using quantitative cell-cell adhesion assay. U937 cells made more cell-cell clusters by the treatment of antibodies to CD29 and CD43 than Jurkat T cells, while Jurkat T cells exhibited increased cell-cell adhesion ability in CD98 antibody treatment. In agreement, the surface levels of CD29 and CD98 were highly observed in U937 and Jurkat T cells, respectively. Therefore, our data suggest that Jurkat T and U937 cells can be used for model system to evaluate functional activation of adhesion molecules such as CD29 and CD98.

• Journal of Microbiology and Biotechnology
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• v.33 no.3
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• pp.339-347
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• 2023

Transforming growth factor-β is a key factor in regulating adhesion formation during tendon healing. We investigated the effectiveness of SMAD family members, SMAD7 and SMAD3, in the TGF-β/Smad signaling during flexor tendon repair. Mouse flexor toe deep tendon rupture anastomosis models were made. On days 3, 7, 14, 21, and 28, the expressions of smad7 and smad3 in flexor tendon tissues were detected by RT-qPCR and western blot. Furthermore, postoperative intraperitoneal injections of SMAD7 agonists or SMAD3 antagonists were given. The degree of tendon healing was evaluated by adhesion testing and biomechanical experiments. Hematoxylin and eosin (HE) staining was used to observe the pathological changes. Immunohistochemistry was used to evaluate the expressions of collagen III, SMAD3, and SMAD7. The mRNA levels of matrix metalloproteinases, Mmp2 and Mmp9, and scleraxis (SCX) in flexor tendon tissue were detected by RT-qPCR. Smad3 expression increased and Smad7 expression decreased in flexor tendon tissue after injury. In addition, the SMAD7 agonist blocked SMAD3 phosphorylation. SMAD7 agonist and SMAD3 antagonist both improved adhesion formation during flexor tendon healing, and decreased the expressions of collagen III, Mmp9, and SCX, while increasing Mmp2 expression. This study provides a possible theoretical basis for the SMAD7-SMAD3 signal cascade during flexor tendon adhesion healing.

• Journal of Adhesion and Interface
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• v.24 no.4
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• pp.113-119
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• 2023

Since it was reported that the unusual amino acid DOPA in synergy with lysine and histidine residues found in mussel adhesive proteins plays a pivotal role in mussel adhesion in underwater environments, there has been a burgeoning development of various catecholamines-based adhesives for biomedical applications. Among these, catechol-conjugated chitosan, containing catecholamine, featuring multiple catechol groups within its aminerich chitosan backbone, has found versatile utility in fields, such as tissue adhesion, wound dressing, tissue healing, hemostats, drug delivery systems, and tissue engineering scaffolds. Significantly, chitosan-catechol is a mussel-inspired material approved by both US Food and Drug Administration (FDA) and KR Ministry of Food and Drug Safety (MFDS) for its effectiveness in hemostasis. This review focuses on 1) general aspects of catechol-conjugated chitosan, highlighting catechol group integration into chitosan backbones, 2) examination of proposed mechanisms of hemostasis, and 3) exploration of diverse physical forms, including solution, hydrogels, patches, and thin films with practical applications inapplicable to hemostasis.

• Journal of Korean Neurosurgical Society
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• v.49 no.6
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• pp.323-328
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• 2011

Objective : Epidural fibrosis and adhesion are the main reasons for post-laminectomy sustained pain and functional disability. In this study, the authors investigate the effect of irradiated freeze-dried human amniotic membrane on reducing epidural adhesion after laminectomy on a rat model. Methods : A total of 20 rats were divided into two groups. The group A did not receive human amniotic membrane implantation after laminectomy and group B underwent human amniotic membrane implantation after laminectomy. Gross and microscopic findings were evaluated and compared at postoperative 1, 3 and 8 weeks. Results : The amount of scar tissue and tenacity were reduced grossly in group of rats with human amniotic membrane implantation (group B). On a microscopic evaluation, there were less inflammatory cell infiltration and fibroblast proliferation in group B. Conclusion : This experimental study shows that implantation of irradiated freeze-dried human amniotic membrane reduce epidural fibrosis and adhesion after spinal laminectomy in a rat model.