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1.
Aesthetic Plast Surg ; 48(9): 1706-1714, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38519570

RESUMO

BACKGROUND: Traditional facial aging surgeries have risks and extended recovery times, leading to a demand for minimally invasive alternatives. PDO (polydioxanone) threads, which are absorbable sutures that stimulate collagen production and tissue contraction, offer improved aesthetic outcomes. This paper evaluates the combined use of PDO thread mid-cheek lift and lower blepharoplasty for facial rejuvenation. METHODS: This retrospective study compared outcomes in patients undergoing lower blepharoplasty combined with a mid-face lift using PDO threads versus those undergoing only lower blepharoplasty. Focused on individuals with baggy lower eyelids and pronounced nasolabial folds, outcome measures included the Modified Fitzpatrick wrinkle scale, Allergan® midface volume deficit scale, Width of inter zygomatic distance, Patient and Observer Scar Assessment Scale, and patient satisfaction questionnaires, assessed at baseline, 3 months, and 1 year postoperatively. RESULTS: The combined procedure demonstrated superior aesthetic outcomes and higher patient satisfaction compared to lower blepharoplasty alone. Improvements were more significant in wrinkle reduction, midface volume, and inter-zygomatic distance in the combined procedure group. Although the combined procedure had a longer mean operation time, scar assessment scores were similar between both groups, with no complications reported. CONCLUSION: The combination of lower blepharoplasty and mid-face lift using PDO threads is a comprehensive and effective approach for facial rejuvenation. It significantly enhances wrinkle reduction, mid-face lifting, and patient satisfaction. Ultrasound-guided thread lifting, a method of assessing and performing mid-face lifting, proves to be safe and efficient. This approach holds promise as a future option in cosmetic anti-aging surgery, presenting a minimally invasive alternative with natural-looking results and reduced downtime. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors https://link.springer.com/journal/00266 .


Assuntos
Blefaroplastia , Satisfação do Paciente , Polidioxanona , Rejuvenescimento , Ritidoplastia , Envelhecimento da Pele , Humanos , Blefaroplastia/métodos , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Ritidoplastia/métodos , Masculino , Resultado do Tratamento , Estética , Idoso , Adulto , Técnicas de Sutura , Suturas , Estudos de Coortes
2.
Aesthetic Plast Surg ; 43(1): 46-52, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30288565

RESUMO

INTRODUCTION: We describe the first case of a patient who received AQUAfilling® gel (Biomedica, Prague, Czech Republic) after augmentation with Poly Implant Prothèse® (PIP) breast implants and later developed breast deformity with bilateral implant rupture. CASE REPORT: A 49-year-old Korean female patient who received breast augmentation with PIP implants 18 years ago and subsequent insertion of AQUAfilling® gel 1 year ago visited our center with a chief complaint of pain and decreased implant sizes in both breasts. Breast implant and foreign body removal operation was performed for both breasts under general anesthesia. Intraoperative gross findings, pathologic findings, and tissue culture results were analyzed. RESULTS: Our diagnosis included rupture of the implants in both breasts with leakage of injected material resulting in inflammation of the pericapsular area and pectoralis muscle. The intraoperative gross findings and results of the pathologic report showed that the implants were exposed with massive leakage of AQUAfilling® gel in the pericapsular space, and the pectoralis major was mixed with AQUAfilling® gel-like liquid and tissue with an inflammatory reaction. CONCLUSIONS: Surgeons should be careful in performing AQUAfilling® gel injection for breast augmentation, especially when combined with breast implant insertion. AQUAfilling® gel itself is not yet proven safe in the long term, so more research on this topic is warranted. Additionally, surgeons should be aware of the comparatively high risk of implant rupture and foreign body reaction with PIP implants, and warn patients accordingly. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Implante Mamário/efeitos adversos , Implantes de Mama/efeitos adversos , Remoção de Dispositivo , Falha de Prótese , Reoperação/métodos , Implante Mamário/métodos , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Desenho de Prótese , Medição de Risco , Ruptura Espontânea/diagnóstico por imagem , Géis de Silicone , Resultado do Tratamento , Ultrassonografia Doppler/métodos
3.
Adv Exp Med Biol ; 1077: 527-537, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30357707

RESUMO

Wound healing is a complex mechanism involving a variety of factors and is a representative process of tissue growth and regeneration in our body. Surface-based interactions between the dressing material and the wound may significantly influence the healing phase. Advances in understanding the mechanism of wound healing have led to the development of numerous dressing materials that can accelerate the healing process. However, these materials have a passive role in wound healing. It is therefore necessary to develop novel wound dressing materials, especially effective for clinically problematic wounds. Chitosan-based dressing materials are considered suitable for clinically problematic wounds as they exhibit several characteristic features, such as facilitating hemostasis, enhanced wound healing during the inflammatory and proliferative phases, antimicrobial effect, etc. Here, we review the current status of clinically available dressing materials and studies on the biological characteristics of chitosan, and discuss the potential applications of chitosan in multi-functional dressing materials for accelarated wound healing.


Assuntos
Bandagens , Quitosana , Cicatrização , Materiais Biocompatíveis , Hemostasia , Humanos
4.
Biomacromolecules ; 17(3): 841-51, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26878437

RESUMO

Hyaluronic acid (HAc) hydrogel exhibits excellent biocompatibility, but it has limited biomedical application due to its poor biomechanical properties as well as too-fast enzymatic degradation. In this study, we have developed an in situ precipitation process for the fabrication of a HAc-calcium phosphate nanocomposite hydrogel, after the formation of the glycidyl methacrylate-conjugated HAc (GMHA) hydrogels via photo-cross-linking, to improve the mechanical and biological properties under physiological conditions. In particular, our process facilitates the rapid incorporation of calcium phosphate (CaP) nanoparticles of uniform size and with minimal agglomeration into a polymer matrix, homogeneously. Compared with pure HAc, the nanocomposite hydrogels exhibit improved mechanical behavior. Specifically, the shear modulus is improved by a factor of 4. The biostability of the nanocomposite hydrogel was also significantly improved compared with that of pure HAc hydrogels under both in vitro and in vivo conditions.


Assuntos
Materiais Biocompatíveis/síntese química , Hidrogéis/síntese química , Nanocompostos/química , Animais , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Linhagem Celular , Ácido Hialurônico/química , Hidrogéis/efeitos adversos , Hidrogéis/química , Camundongos , Nanocompostos/efeitos adversos
6.
Ann Plast Surg ; 72(1): 50-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24343319

RESUMO

The purpose of this study was to analyze the statistical association between variable clinical phenotypes of the orbit, mandible, ear, nerve, soft tissue (OMENS) classification system in Oriental patients with hemifacial microsomia (HFM) and compare the data of Oriental children with data from other Western centers. One hundred consecutive patients with HFM referred to the Seoul National University Children Hospital were chosen between March 2009 and April 2010. They were classified according to the OMENS classification system, and statistical analyses were performed. The total OMENS scores were correlated significantly with all 5 component scores. In comparison with the previous data of Western centers, the orbit and ear components had statistically higher severity. Our retrospective study in Oriental children demonstrated that the pathophysiology of HFM is a complex process and that the components of HFM have a close relationship. For the ethnic difference, further etiologic studies on the molecular basis are required.


Assuntos
Povo Asiático , Síndrome de Goldenhar/classificação , Síndrome de Goldenhar/etnologia , Fenótipo , Índice de Gravidade de Doença , Feminino , Humanos , Masculino , República da Coreia , Estudos Retrospectivos , Estatísticas não Paramétricas
7.
Ann Plast Surg ; 73(3): 311-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24374402

RESUMO

The purpose of this study was to statistically analyze mandibular growth disturbance in the Oriental cleft population and compare this with that of non-cleft children through cephalometric analysis. Thirty-six children with cleft palates, repaired using a modification of Furlow double opposing Z-plasty, were chosen. Comparative analyses among 3 types of cleft were performed. Statistical analyses of 8 linear and angular measurements were performed in cleft patients and the non-cleft population using Fisher Z-transformation. Comparative analysis showed no significant difference among the 3 types of cleft. In the Oriental cleft group treated with modified double opposing Z-plasty, the spatial position of the mandible showed significant differences compared with the non-cleft group. A backward inclination of the anterior surface of the mandible and downward rotation of the mandibular body were identified. Some of our results regarding gonial angle and length of the mandibular body conflicted with previous Western studies.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Mandíbula/crescimento & desenvolvimento , Povo Asiático , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos
8.
Acta Biomater ; 171: 378-391, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37683967

RESUMO

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) occurs in the capsule surrounding breast implants. Malignant transformation of T cells by bacteria-driven chronic inflammation may be underlying BIA-ALCL mechanism. Here, we covalently grafted 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymers on a silicone surface and examined its effects against BIA-ALCL pathogenesis. MPC grafting strongly inhibited the adhesion of bacteria and bacteria-causing inflammation. Additionally, cancer T cell proliferation and capsule-derived fibroblast-cancer cell communication were effectively inhibited by MPC grafting. We further demonstrated the effect of MPC against the immune responses causing BIA-ALCL around human silicone implants in micro-pigs. Finally, we generated a xenograft anaplastic T cell lymphoma mouse model around the silicone implants and demonstrated that MPC grafting could effectively inhibit the lymphoma progression. This study is the first to show that bacteria-driven induction and progression of BIA-ALCL can be effectively inhibited by surface modification of implants. STATEMENT OF SIGNIFICANCE: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a major concern in the field of plastic and reconstructive surgery. In this study, we demonstrate strong inhibitory effect of zwitterionic polymer grafting on BIA-ALCL pathogenesis and progression, induced by bacterial infection and inflammation, both in vitro and in vivo. This study provides a molecular basis for the development of novel breast implants that can prevent various potential complications such as excessive capsular contracture, breast implant illness, and BIA-ALCL incidence, as well as for expanding the biomedical applications of zwitterionic polymers.


Assuntos
Implantes de Mama , Neoplasias da Mama , Linfoma Anaplásico de Células Grandes , Humanos , Animais , Camundongos , Suínos , Feminino , Implantes de Mama/efeitos adversos , Linfoma Anaplásico de Células Grandes/etiologia , Linfoma Anaplásico de Células Grandes/epidemiologia , Linfoma Anaplásico de Células Grandes/patologia , Bactérias , Inflamação , Silicones
9.
Macromol Biosci ; 22(8): e2200081, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35698278

RESUMO

Currently, dermal fillers are largely based on commercialized cross-linked hyaluronic acid (HA) injections, which require a large injection force. Additionally, HA can be easily decomposed by enzymes, and HA-treated tissues present a risk of developing granuloma. In this study, a chitosan-based dermal filler is presented that operates on a liquid-to-gel transition and allows the injection force to be kept ≈4.7 times lower than that required for HA injections. Evaluation of the physical properties of the chitosan filler indicates high viscoelasticity and recovery rate after gelation at 37 °C. Furthermore, in an in vivo evaluation, the liquid injection-type chitosan filler transitions to a gel state within 5 min after injection into the body, and exhibits a compressive strength that is ≈2.4 times higher than that of cross-linked HA. The filler also exhibits higher moldability and maintains a constant volume in the skin for a longer time than the commercial HA filler. Therefore, it is expected that the chitosan filler will be clinically applicable as a novel material for dermal tissue restoration and supplementation.


Assuntos
Quitosana , Preenchedores Dérmicos , Materiais Biocompatíveis , Elasticidade , Ácido Hialurônico
10.
Biomater Sci ; 8(6): 1580-1591, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-31932833

RESUMO

Implants based on silicone elastomers, polydimethylsiloxane (PDMS), have been widely used for breast augmentation and reconstruction, but excessive foreign body reactions around implants often cause serious side effects such as capsular contracture. In our previous study, we covalently grafted 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymers on the surface of PDMS blocks by UV-induced polymerization and showed effective reduction of capsular formation around the MPC-grafted PDMS in rats. In the present study, we examined the efficacy of heat-induced polymerization of MPC grafting on silicone breast implants intended for humans, and analyzed the in vivo inhibitory effect against capsular formation and inflammation in pigs, which are closely related to humans in terms of epidermal structures and fibrotic processes. The heat-induced polymerization provided a thicker MPC-grafted surface and was more effective than UV-induced polymerization for the grafting of complex shaped non-transparent implants. After 24-week implantation in the submuscular pockets of Yorkshire pigs, the heat-induced MPC-grafted breast implants showed 45% smaller capsular thickness and 20-30% lower levels of inflammatory markers such as myeloperoxidase (MPO), transforming growth factor-ß (TGF-ß), and α-smooth muscle actin (α-SMA) in surrounding tissues compared to non-grafted implants. This study provides important information for future clinical trials of MPC-grafted silicone implants.


Assuntos
Implantes de Mama/efeitos adversos , Dimetilpolisiloxanos/química , Reação a Corpo Estranho/prevenção & controle , Metacrilatos/química , Fosforilcolina/análogos & derivados , Animais , Modelos Animais de Doenças , Feminino , Temperatura Alta , Humanos , Fosforilcolina/química , Polimerização , Propriedades de Superfície , Suínos , Raios Ultravioleta
11.
ACS Appl Mater Interfaces ; 12(27): 30198-30212, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32574031

RESUMO

The surface of human silicone breast implants is covalently grafted at a high density with a 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymer. Addition of cross-linkers is essential for enhancing the density and mechanical durability of the MPC graft. The MPC graft strongly inhibits not only adsorption but also the conformational deformation of fibrinogen, resulting in the exposure of a buried amino acid sequence, γ377-395, which is recognized by inflammatory cells. Furthermore, the numbers of adhered macrophages and the amounts of released cytokines (MIP-1α, MIP-1ß, IL-8, TNFα, IL-1α, IL-1ß, and IL-10) are dramatically decreased when the MPC network is introduced at a high density on the silicone surface (cross-linked PMPC-silicone). We insert the MPC-grafted human silicone breast implants into Yorkshire pigs to analyze the in vivo effect of the MPC graft on the capsular formation around the implants. After 6 month implantation, marked reductions of inflammatory cell recruitment, inflammatory-related proteins (TGF-ß and myeloperoxidase), a myoblast marker (α-smooth muscle actin), vascularity-related factors (blood vessels and VEGF), and, most importantly, capsular thickness are observed on the cross-linked PMPC-silicone. We propose a mechanism of the MPC grafting effect on fibrous capsular formation around silicone implants on the basis of the in vitro and in vivo results.


Assuntos
Metacrilatos/química , Fosforilcolina/análogos & derivados , Polímeros/química , Animais , Quimiocina CCL4/metabolismo , Fibrinogênio/química , Macrófagos/metabolismo , Fosforilcolina/química , Silicones/química , Suínos
12.
Biomater Sci ; 7(7): 2907-2919, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31089612

RESUMO

Although the design of more biocompatible polymeric implants has been studied for decades, their intended functionality continues to be impaired by the response of the host tissue to foreign bodies at the tissue-implant interface. In particular, the formation and contracture of fibrous capsules prevent the intimate integration of an implant with surrounding tissues, which leads to structural deformation of the implants and persistent discomfort and pain. We report a new surface nano-engineered silicone implant that reduces fibrous capsule formation and improves the biocompatibility of it via sputtering-based plasma immersion ion implantation (S-PIII). This technique can introduce biologically compatible tantalum (Ta) on the silicone surface to produce a Ta-implanted skin layer (<60 nm thick) as well as generate either smooth (Smooth/Ta silicone) or nano-textured (Nano/Ta silicone) surface morphologies. The biologically inert chemical structure and strong hydrophobic surface characteristics of bare silicone are substantially ameliorated after Ta ion implantation. In particular, the Nano/Ta silicone implant's combination of surface nano-texturing as a physical cue and the Ta-implanted layer as a chemical cue was found to be very effective at achieving outstanding hydrophilicity and fibroblast affinity compared to the bare and Smooth/Ta silicone implants. In a mouse in vivo study conducted for 8 weeks, the Nano/Ta silicone implant inhibited fibrous capsule formation and contracture on its surface better than the bare silicone based on an analysis of the number of macrophages, myofibroblast differentiation and activation, collagen density, and thickness of fibrous capsules.


Assuntos
Engenharia , Nanotecnologia , Próteses e Implantes , Silicones/química , Tantálio/química , Animais , Fibroblastos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fenômenos Mecânicos , Ativação Plaquetária/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Silicones/farmacologia , Propriedades de Superfície
13.
Int J Biol Macromol ; 123: 866-877, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30447366

RESUMO

The creation of a moist environment and promotion of cell proliferation and migration together with antibacterial property are critical to the wound-healing process. Alginate (Alg) is an excellent candidate for injectable wound dressing materials because it can form a gel in a mild environment. Taking advantage of its gelation property, an injectable nano composite hydrogel containing nano-sized (about 90 nm) calcium fluoride (CaF2) particles was developed using in-situ precipitation process. The amount of released fluorine (F-) ion from the nanocomposite hydrogel increased with increasing CaF2 content inside the composite hydrogel and the ions stimulated both the proliferation and migration of fibroblast cells in vitro. The antibacterial property of the composite hydrogel against E. coli and S. aureus was confirmed through colony formation test where the number of bacterial colonies significantly decreased compared to Alg hydrogel. The in vivo results based on a full-thickness wound model showed that the nanocomposite hydrogel effectively enhanced the deposition of the extracellular matrix compared to that of the Alg hydrogel. This study demonstrates the potential of this nanocomposite hydrogel as a bioactive injectable wound-dressing material with the ability to inhibit bacterial growth and stimulate cell proliferation and migration for accelerated wound healing.


Assuntos
Alginatos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Flúor/farmacologia , Hidrogéis/química , Injeções , Nanocompostos/química , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Precipitação Química , Reagentes de Ligações Cruzadas/química , Escherichia coli/efeitos dos fármacos , Inflamação/patologia , Íons , Masculino , Camundongos , Nanocompostos/ultraestrutura , Ratos Sprague-Dawley , Reologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Difração de Raios X
14.
J Biomater Appl ; 32(8): 1011-1023, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29357774

RESUMO

In this study, we evaluated the surface characterization of a novel chitosan-silica hybridized membrane and highlighted the substantial role of silica in the wound environment. The chemical coupling of chitosan and silica resulted in a more condensed network compared with pure chitosan, which was eventually able to stably maintain its framework, particularly in the wet state. In addition, we closely observed the wound-healing process along with the surface interaction between chitosan-silica and the wound site using large-surface-area wounds in a porcine model. Our evidence indicates that chitosan-silica exerts a synergetic effect of both materials to promote a remarkable wound-healing process. In particular, the silica in chitosan-silica accelerated wound closure including wound contraction, and re-epithelialization via enhancement of cell recruitment, epidermal maturity, neovascularization, and granulation tissue formation compared with pure chitosan and other commercial dressing materials. This advanced wound dressing material may lead to effective treatment for problematic cutaneous wounds and can be further applied for human skin regeneration.


Assuntos
Bandagens , Materiais Biocompatíveis/uso terapêutico , Quitosana/uso terapêutico , Dióxido de Silício/uso terapêutico , Pele/lesões , Cicatrização , Animais , Materiais Biocompatíveis/química , Proliferação de Células , Quitosana/química , Interações Hidrofóbicas e Hidrofílicas , Masculino , Membranas Artificiais , Neovascularização Fisiológica , Porosidade , Dióxido de Silício/química , Pele/irrigação sanguínea , Pele/patologia , Suínos
15.
Biomed Res Int ; 2018: 3167037, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854742

RESUMO

Although silicone implants are widely used in breast and other reconstructive surgeries, the limited biocompatibility of these materials leads to severe complications, including capsular contracture. Here, we aimed to clarify the relationship between periostin and the process of capsule formation after in vivo implantation. Seven-week-old wild-type (WT) C57BL/6 mice and periostin-deficient mice were used. Round silicone implants were inserted into a subcutaneous pocket on the dorsum of the mice. After 8 weeks, the fibrous capsule around the implant was harvested and histologically examined to estimate capsular thickness and the number of inflammatory cells. Additionally, immunohistochemical analysis (periostin, α-SMA, and collagen type I) and western blotting (CTGF, TGF-ß, VEGF, and MPO) were performed for a more detailed analysis of capsule formation. The capsules in periostin-knockout mice (PN-KO) were significantly thinner than those in WT mice. PN-KO mice showed significantly lower numbers of inflammatory cells than WT mice. Fibrous tissue formation markers (α-SMA, periostin, collagen type I, and CTGF) were significantly reduced in PN-KO mice. We also confirmed that inflammatory reaction and angiogenesis indicators (TGF-ß, MPO, and VEGF) had lower expression in PN-KO mice. Inhibition of periostin could be important for suppressing capsule formation on silicone implants after in vivo implantation.


Assuntos
Implantes de Mama/efeitos adversos , Moléculas de Adesão Celular/metabolismo , Falha de Prótese , Silicones/efeitos adversos , Animais , Western Blotting , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Imuno-Histoquímica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peroxidase/metabolismo , Implantação de Prótese , Fator de Crescimento Transformador beta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Mater Sci Eng C Mater Biol Appl ; 79: 866-874, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28629091

RESUMO

Polyurethane (PU)-based dressing foams have been widely used due to their excellent water absorption capability, optimal mechanical properties, and unequaled economic advantage. However, the low bioactivity and poor healing capability of PU limit the applications of PU dressings in complex wound healing cases. To resolve this problem, this study was carried out the hybridization of bioactive silica nanoparticles with PU through a one-step foaming reaction that is coupled with the sol-gel process. The hybridization with silica did not affect the intrinsically porous microstructure of PU foams with silica contents of up to 10wt% and where 5-60nm silica nanoparticles were well dispersed in the PU matrix, despite slight agglomerations. The incorporated silica enhanced the mechanical performance of PU by proffering better flexibility and durability as well as maintaining good water absorption capabilities and the WVTR characteristics of pure PU foam. The silica of PU-10wt% Si foams was gradually dissolved and released under physiological conditions during a 14-day immersion period. The in vitro cell attachment and proliferation tests showed significant improvements in terms of the biocompatibility of PU-Si hybrid foams and demonstrated the effects of silica on cell growth. More significantly, the superior healing capability of PU-Si as a wound dressing in comparison to PU-treated wounds was verified through in vivo animal tests. Full-thickness wounds treated with PU-Si foams exhibited faster wound closure rates as well as accelerated collagen and elastin fiber regeneration in newly formed dermis, which was ultimately completely covered by a new epithelial layer. It is clear that PU-Si hybrid foams have considerable potential as a wound dressing material geared for accelerated, superior wound healing.


Assuntos
Transição de Fase , Animais , Bandagens , Derme , Poliuretanos , Dióxido de Silício , Cicatrização
17.
Acta Biomater ; 10(10): 4217-25, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25020265

RESUMO

Despite their popular use in breast augmentation and reconstruction surgeries, the limited biocompatibility of silicone implants can induce severe side effects, including capsular contracture - an excessive foreign body reaction that forms a tight and hard fibrous capsule around the implant. This study examines the effects of using biomembrane-mimicking surface coatings to prevent capsular formations on silicone implants. The covalently attached biomembrane-mimicking polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), prevented nonspecific protein adsorption and fibroblast adhesion on the silicone surface. More importantly, in vivo capsule formations around PMPC-grafted silicone implants in rats were significantly thinner and exhibited lower collagen densities and more regular collagen alignments than bare silicone implants. The observed decrease in α-smooth muscle actin also supported the alleviation of capsular formations by the biomembrane-mimicking coating. Decreases in inflammation-related cells, myeloperoxidase and transforming growth factor-ß resulted in reduced inflammation in the capsular tissue. The biomembrane-mimicking coatings used on these silicone implants demonstrate great potential for preventing capsular contracture and developing biocompatible materials for various biomedical applications.


Assuntos
Materiais Biomiméticos , Implantes de Mama , Materiais Revestidos Biocompatíveis , Teste de Materiais , Membranas Artificiais , Silicones , Actinas/biossíntese , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Feminino , Camundongos , Células NIH 3T3 , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/metabolismo , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/metabolismo , Ratos , Ratos Sprague-Dawley , Silicones/química , Silicones/farmacologia , Fator de Crescimento Transformador beta/biossíntese
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