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1.
Molecules ; 27(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014376

RESUMO

The skin tissue of the scalp is unique from other skin tissues because it coexists with hair, and many differences in microbial composition have been confirmed. In scalp tissues, hair loss occurs due to a combination of internal and external factors, and several studies are being conducted to counteract this. However, not many studies have addressed hair loss from the perspective of the microbiome. In this study, subjects with hair loss and those with normal scalps were set as experimental and control groups, respectively. In the experimental group, hair loss had progressed, and there was a large difference in microbiome composition compared to the group with normal scalps. In particular, differences in Accumulibacter, Staphylococcus, and Corynebacterium were found. From Staphylococcus epidermidis Cicaria, two active components were isolated as a result of repeated column chromatography. Spectroscopic data led to the determination of chemical structures for adenosine and biotin. Fractions were obtained, and ex vivo tests were conducted using hair follicles derived from human scalp tissue. When the microbiome adenosine-treated group was compared to the control group, hair follicle length was increased, and hair root diameter was maintained during the experimental periods. In addition, the Cicaria culture medium and the microbial adenosine- and biotin-treated groups maintained the anagen phase, reducing progression to the catagen phase in the hair growth cycle. In conclusion, it was confirmed that the Cicaria culture medium and the microbial adenosine and biotin derived from the culture were effective in inhibiting hair loss.


Assuntos
Microbiota , Staphylococcus epidermidis , Adenosina , Alopecia , Biotina , Folículo Piloso , Humanos
2.
Bioeng Transl Med ; 8(1): e10320, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684080

RESUMO

Self-injectable therapy has several advantages in the treatment of metabolic disorders. However, frequent injections with needles impair patient compliance and medication adherence. Therefore, we develop a fully implantable device capable of on-demand administration of self-injection drugs via noninvasive manual button clicks on the outer skin. The device is designed to infuse the drug only at the moment of click actuation, which allows for an accurate and reproducible drug infusion, and also prevents unwanted drug leakage. Using a mechanical means of drug infusion, this implantable device does not contain any electronic compartments or batteries, making it compact, and semi-permanent. When tested in animals, the device can achieve subcutaneous injection-like pharmacokinetic and pharmacodynamic effects for self-injection drugs such as exenatide, insulin, and glucagon.

3.
In Vivo ; 37(3): 1093-1102, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37103107

RESUMO

BACKGROUND/AIM: This research investigated the biophysical properties, safety, and efficacy of polydioxanone (PDO) filler compared to poly-L-lactic acid (PLLA), polycaprolactone (PCL), and hyaluronic acid (HA) fillers. In both mouse and human skin models, a novel collagen stimulation was compared with hyaluronic acid filler. MATERIALS AND METHODS: An electron microscope was used to capture images of the solid particle microsphere shape. Moreover, animal models named SKH1-Hrhr were used to assess the 12-week persistence of PDO, PLLA, or PCL filler. H&E and Sirus Red staining were used to compare collagen density. Five participants in the clinical trial received three injections in the dermis over an eight-month period. Skin density, wrinkles, and gloss were evaluated using DUB® skin scanner, Antera 3D CS, Mark-Vu, and Skin gloss meter after injection to assess the efficacy of fillers. RESULTS: PDO microspheres had uneven surfaces and were spherical and consistent in size. In comparison to other fillers, the PDO filler demonstrated complete biodegradability in just 12 weeks and better neocollagenesis, and a lower inflammatory response than the HA filler. After three injections, the human body assay showed a significant improvement in skin gloss, wrinkles, and density. CONCLUSION: In comparison to PCL and PLLA, PDO filler demonstrated a comparable volume increase rate and better biodegradability. Furthermore, although its physical characteristics are similar to those of a solid, PDO has the advantage of being more organically spread. In photoaging mice, PDO fillers are thought to offer equivalent or superior anti-wrinkle and anti-aging effects to PBS, PCL, and PLLA.


Assuntos
Preenchedores Dérmicos , Humanos , Camundongos , Animais , Preenchedores Dérmicos/efeitos adversos , Ácido Hialurônico , Pele , Modelos Animais de Doenças , Colágeno
4.
Bioeng Transl Med ; 7(1): e10260, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35111952

RESUMO

Medical devices made from poly(dimethylsiloxane) (PDMS)-based silicone implants have been broadly used owing to their inert properties, biocompatibility, and low toxicity. However, long-term implantation is usually associated with complications, such as capsular contracture due to excessive local inflammatory response, subsequently requiring implant removal. Therefore, modification of the silicone surface to reduce a risk of capsular contracture has attracted increasing attention. Human adipose-derived stem cells (hASCs) are known to provide potentially therapeutic applications for tissue engineering, regenerative medicine, and reconstructive surgery. Herein, hASCs coating on a PDMS (hASC-PDMS) or itaconic acid (IA)-conjugated PDMS (hASC-IA-PDMS) surface is examined to determine its biocompatibility for reducing capsular contracture on the PDMS surface. In vitro cell cytotoxicity evaluation showed that hASCs on IA-PDMS exhibit higher cell viability than hASCs on PDMS. A lower release of proinflammatory cytokines is observed in hASC-PDMS and hASC-IA-PDMS compared to the cells on plate. Multiple factors, including in vivo mRNA expression levels of cytokines related to fibrosis; number of inflammatory cells; number of macrophages and myofibroblasts; capsule thickness; and collagen density following implantation in rats for 60 days, indicate that incorporated coating hASCs on PDMSs most effectively reduces capsular contracture. This study demonstrates the potential of hASCs coating for the modification of PDMS surfaces in enhancing surface biocompatibility for reducing capsular contracture of PDMS-based medical devices.

5.
Mater Sci Eng C Mater Biol Appl ; 135: 112687, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35581080

RESUMO

Conventionally, macro-textured surfaces comprising several hundred micrometer-sized patterns are used to minimize silicone-based breast implant complications, including capsular contracture. However, because of the recent cases of breast implant-associated anaplastic large cell lymphoma from macro-textured implants, there is a strong demand for nano- or micro-textured silicone implants with dimensions smaller than sub-micrometers. Herein, we propose a simple and cost-effective topographical surface modification strategy for silicone-based implants. Several hundred nanometer to sub-micrometer wide groove-type micro-textures were fabricated on a polydimethylsiloxane surface using electrospun polyvinylpyrrolidone fibers as a sacrificial template. The aligned and randomly oriented micro-textures were prepared by controlling the electrospun fiber orientation. In vitro experiments demonstrated that the micro-textured polydimethylsiloxane was cytocompatible and suppressed differentiation of fibroblasts into myofibroblasts. Importantly, the aligned micro-texture promoted the polarization of macrophages into the anti-inflammatory M2 phenotype. Long-term in vivo studies established that the micro-textures potently suppressed various factors affecting foreign body reactions by downregulating profibrotic cytokine gene expression and reducing the fibroblast and myofibroblast counts, the cells playing important roles in the immune response. Thus, the thickness and collagen density of fibrous capsules were decreased, demonstrating that the micro-textured surface effectively inhibited capsular contracture. Although the aligned micro-textures contributed to the polarization of macrophages to the M2 phenotype both in vitro and in vivo, foreign body reaction by both the aligned and randomly oriented micro-textures are similar.


Assuntos
Implantes de Mama , Contratura , Dimetilpolisiloxanos , Fibrose , Humanos , Silicones , Propriedades de Superfície
6.
PLoS One ; 17(12): e0277188, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36508415

RESUMO

Various substances, including collagen (Naticol®) and ascorbic acid, that inhibit and prevent skin aging have been studied. Collagen prevents skin aging, has anti-inflammatory effects, and assists in normal wound healing. Ascorbic acid is a representative antioxidant that plays a role in collagen synthesis. To achieve a synergistic effect of collagen and ascorbic acid on all skin types, we prepared a product named "TEENIALL." In addition, we used a container to separate ascorbic acid and collagen to prevent the oxidation of ascorbic acid. To confirm the effects of TEENIALL, we first confirmed its penetrability in fibroblasts, keratinocytes, melanocyte, and human skin tissues. Thereafter, we confirmed the collagen synthesis ability in normal human fibroblasts. Based on the results of in vitro tests, we conducted a clinical trial (KCT0006916) on female volunteers, aged 40 to 59 years, with skin wrinkles and hyperpigmentation, to evaluate the effects of the product in improving skin wrinkles, skin lifting, and pigmentation areas before using the product, and after 2 and 4 weeks of using the product. The values of nine wrinkle parameters that were evaluated decreased and those for skin sagging, pigmentation, dermal density, and mechanical imprint (pressure) relief were improved. Skin wrinkle and pigmentation were evaluated to ensure that the improvement effect was maintained even after 1 week of discontinuing the product use. The evaluation confirmed that the effects were sustained compared to those after 4 weeks of using the product. Additionally, skin wrinkles, skin lifting, radiance, and moisture content in the skin improved immediately after using the product once. Based on the results of in vitro and ex vivo experiments and the clinical trial, we show that the product containing ascorbic acid and collagen was effective in alleviating skin aging.


Assuntos
Ácido Ascórbico , Envelhecimento da Pele , Feminino , Humanos , Ácido Ascórbico/farmacologia , Colágeno/farmacologia , Pele , Fibroblastos
7.
J Cosmet Dermatol ; 20(9): 2743-2749, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33421303

RESUMO

BACKGROUND: Polydioxanone (PDO) threads, poly-L-lactic acid (PLLA) threads, and polycaprolactone (PCL) threads have been used for lifting and antiaging purposes. The new PCL threads that have less residual monomer compared to the previous PCL are developed. AIMS: The efficacy of threads regarding collagen synthesis and wrinkle improvement was evaluated in vivo model. METHODS: In this study, threads were inserted into 30 six-week-old male SKH-1 hairless mice. One of four threads was implanted at either side of the spine of each mouse. Biopsy specimens obtained at 1, 4, and 8 weeks were examined using hematoxylin and eosin (H&E) and Herovici's stain. Additionally, immunoblot analysis was performed using primary antibody for collagen type III and transforming growth factor-ß (TGF-ß) and visualized by chemiluminescence and densitometric quantification. Finally, skin replicas were used to calculate total wrinkle area (mm2 ). RESULTS: Neocollagenesis was significantly increased by 50% in the new PCL and pre-existing PCL groups at 8 weeks (p value < 0.001). Additionally, new-PCL-implanted mice showed a significant increase in collagen type III and TGF-ß expressions at 8 weeks (p value < 0.001). The number of inflammatory cells was also increased in the skin of PCL-implanted mice at 8 weeks. Finally, wrinkles were reduced about 20% in the new PCL group at 8 weeks. CONCLUSIONS: The new PCL thread exhibited a superior skin rejuvenation effect. This suggests that the material processing technology can be applied not only to the thread but also to various products such as dermal filler and cosmetics.


Assuntos
Polidioxanona , Rejuvenescimento , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Pelados , Poliésteres
8.
Polymers (Basel) ; 13(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34451169

RESUMO

Breast augmentations with silicone implants can have adverse effects on tissues that, in turn, lead to capsular contracture (CC). One of the potential ways of overcoming CC is to control the implant/host interaction using immunomodulatory agents. Recently, a high ratio of anti-inflammatory (M2) macrophages to pro-inflammatory (M1) macrophages has been reported to be an effective tissue regeneration approach at the implant site. In this study, a biofunctionalized implant was coated with interleukin (IL)-4 to inhibit an adverse immune reaction and promoted tissue regeneration by promoting polarization of macrophages into the M2 pro-healing phenotype in the long term. Surface wettability, nitrogen content, and atomic force microscopy data clearly showed the successful immobilization of IL-4 on the silicone implant. Furthermore, in vitro results revealed that IL-4-coated implants were able to decrease the secretion of inflammatory cytokines (IL-6 and tumor necrosis factor-α) and induced the production of IL-10 and the upregulation of arginase-1 (mannose receptor expressed by M2 macrophage). The efficacy of this immunomodulatory implant was further demonstrated in an in vivo rat model. The animal study showed that the presence of IL-4 diminished the capsule thickness, the amount of collagen, tissue inflammation, and the infiltration of fibroblasts and myofibroblasts. These results suggest that macrophage phenotype modulation can effectively reduce inflammation and fibrous CC on a silicone implant conjugated with IL-4.

9.
Materials (Basel) ; 14(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34300843

RESUMO

Cosmetic silicone implants for breast reconstruction often lead to medical complications, such as abnormally excessive fibrosis driven by foreign body granulomatous inflammation. The purpose of this study was to develop a silicone breast implant capable of local and controlled release of a glucocorticoid drug triamcinolone acetonide (TA) for the prevention of silicone-breast-implant-induced fibrosis in a Yorkshire pig model (in vivo). Implants were dip-coated in a TA solution to load 1.85 µg/cm2 of TA in the implant shell, which could release the drug in a sustained manner for over 50 days. Immunohistochemical analysis for 12 weeks showed a decline in tumor necrosis factor-α expression, capsule thickness, and collagen density by 82.2%, 55.2%, and 32.3%, respectively. Furthermore, the counts of fibroblasts, macrophages, and myofibroblasts in the TA-coated implants were drastically reduced by 57.78%, 48.8%, and 64.02%, respectively. The TA-coated implants also lowered the expression of vimentin and α-smooth muscle actin proteins, the major profibrotic fibroblast and myofibroblast markers, respectively. Our findings suggest that TA-coated silicone breast implants can be a promising strategy for safely preventing fibrosis around the implants.

10.
Mater Sci Eng C Mater Biol Appl ; 109: 110565, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228902

RESUMO

We propose an elastic net made of a biocompatible polymer to wrap silicone implants of various sizes, which also allows for the sustained release of an anti-inflammatory drug, triamcinolone, to prevent fibrosis. For this, we first prepared a strand composed of a mixture of polyurethane and triamcinolone via electrospinning, which was then assembled to prepare the elastic drug-delivery net (DDN). The DDN was prepared to just fit for wrapping the small silicone implant sample herein, but was also able to wrap a sample 7 times as large at 72% strain due to the elastic property of polyurethane. The DDN exhibited sustained drug release for 4 weeks, the profile of which was not very different between the intact and strained DDNs. When implanted in a subcutaneous pocket in living rats, the DDN-wrapped silicone implant samples showed an obvious antifibrotic effect due to the sustained release of triamcinolone. Importantly, this effect was similar for the small and large silicone samples, both wrapped with the same DDN. Therefore, we conclude that this drug-loaded net made of an elastic, biocompatible polymer has high potential for sustained drug delivery around silicone implants manufactured in various sizes.


Assuntos
Poliuretanos , Silicones , Triancinolona , Animais , Implantes de Medicamento/química , Implantes de Medicamento/farmacocinética , Implantes de Medicamento/farmacologia , Masculino , Poliuretanos/química , Poliuretanos/farmacologia , Ratos , Ratos Sprague-Dawley , Silicones/química , Silicones/farmacologia , Triancinolona/química , Triancinolona/farmacocinética , Triancinolona/farmacologia
11.
J Control Release ; 318: 176-184, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31838204

RESUMO

We propose the use of an implantable device with multiple embedded drug diffusion channels, each of which is connected to a drug reservoir, for the controlled release of diclofenac. To minimize the size of the incision needed during device implantation, the device used herein was made of the soft biocompatible material polydimethylsiloxane (PDMS), thereby allowing for folding during device implantation. We aimed to achieve a profile of diclofenac release that was reproducible even after folding, and thus the channel was filled with cross-linked gelatin, which could be swollen via the infiltration of a bodily fluid to compensate for any possible defects formed during folding. We first assessed the use of individual channels of varying lengths of 1-12 mm, and the onset time and average rate varied from 1 to 14 days and from 0.31-4.3%/day, respectively. According to these results, we prepared a device with multiple integrated pairs of drug reservoirs and channels of different lengths (i.e., the SDD_I), in which the channel combination was selected to achieve the long-term, zero-order release of the largest amount of drug. Thus, the SDD_I used herein exhibited almost zero-order drug release for 55 days at a release rate of 1.19%/day (179.8 µg/day), which did not vary even after the device was folded multiple times due to the presence of gelatin in the channel. When tested in living rats, the SDD_I device could be folded and inserted subcutaneously through an incision less than half the size of that needed for the implantation of the unfolded, intact SDD_I. For both the unfolded and folded SDD_I devices, the drug concentration in blood was observed to be maintained within a similar range due to the almost zero-order, reproducible release of diclofenac.


Assuntos
Diclofenaco , Sistemas de Liberação de Medicamentos , Animais , Preparações de Ação Retardada , Difusão , Gelatina , Ratos
12.
Int Immunopharmacol ; 66: 139-145, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30453147

RESUMO

This study aimed to evaluate the role of NecroX-5, a powerful anti-inflammatory agent, on the functional plasticity of macrophages and the possible underlying mechanism using RAW264.7 cells, thioglycollate-elicited peritoneal macrophages from C57BL/6 mice, and a murine model of dextran sodium sulfate (DSS)-induced colitis. The change in cell morphology was examined by scanning electron microscopy. The expression of CD206, arginase (Arg)-1, and inducible nitric oxide synthase (iNOS) were examined by western blotting. The production of inflammatory cytokines was detected by enzyme-linked immunosorbent assays and statistical comparisons were made. The results showed that treatment of RAW264.7 cells with NecroX-5 caused an elongated shape in comparison to non-treated cells. The expression levels of macrophage mannose receptor CD206 and Arg-1, specific markers of M2 cells, were significantly upregulated by NecroX-5 treatment, while those of iNOS (M1 macrophages) was decreased. In addition, NecroX-5 significantly reduced the secretion of inflammatory cytokines, while interleukin (IL)-4 and IL-13 secretion in the supernatant was significantly enhanced. Treatment with NecroX-5 considerably ameliorated the progression of DSS-induced colitis and significantly inhibited the mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α and IL-1ß. Taken together, our findings demonstrated that NecroX-5 might dampen inflammation by switching the M1 phenotype to the M2 phenotype due to IL-4 and IL-13 induction.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Sulfonas/uso terapêutico , Animais , Diferenciação Celular , Plasticidade Celular , Colite/induzido quimicamente , Citocinas/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , Células Th2/imunologia
13.
Macromol Biosci ; 19(12): e1900206, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31709762

RESUMO

The surface of poly(dimethylsiloxane) (PDMS) is grafted with poly(acrylic acid) (PAA) layers via surface-initiated photopolymerization to suppress the capsular contracture resulting from a foreign body reaction. Owing to the nature of photo-induced polymerization, various PAA micropatterns can be fabricated using photolithography. Hole and stripe micropatterns ≈100-µm wide and 3-µm thick are grafted onto the PDMS surface without delamination. The incorporation of PAA micropatterns provides not only chemical cues by hydrophilic PAA microdomains but also topographical cues by hole or stripe micropatterns. In vitro studies reveal that a PAA-grafted PDMS surface has a lower proliferation of both macrophages (Raw 264.7) and fibroblasts (NIH 3T3) regardless of the pattern presence. However, PDMS with PAA micropatterns, especially stripe micropatterns, minimizes the aggregation of fibroblasts and their subsequent differentiation into myofibroblasts. An in vivo study also shows that PDMS samples with stripe micropatterns polarized macrophages into anti-inflammatory M2 macrophages and most effectively inhibits capsular contracture, which is demonstrated by investigation of inflammation score, transforming-growth-factor-ß expression, number of macrophages, and myofibroblasts as well as the collagen density and capsule thickness.


Assuntos
Resinas Acrílicas/farmacologia , Dimetilpolisiloxanos/farmacologia , Reação a Corpo Estranho/imunologia , Implantes Experimentais , Pele/efeitos dos fármacos , Tela Subcutânea/efeitos dos fármacos , Resinas Acrílicas/química , Animais , Biomarcadores/metabolismo , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dimetilpolisiloxanos/química , Reação a Corpo Estranho/induzido quimicamente , Expressão Gênica/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Células NIH 3T3 , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Pele/imunologia , Pele/metabolismo , Tela Subcutânea/imunologia , Tela Subcutânea/metabolismo , Propriedades de Superfície , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/imunologia
14.
Biomater Res ; 22: 37, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30598837

RESUMO

BACKGROUND: Silicone implants are biomaterials that are frequently used in the medical industry due to their physiological inertness and low toxicity. However, capsular contracture remains a concern in long-term transplantation. To date, several studies have been conducted to overcome this problem. This review summarizes and explores these trends. MAIN BODY: First, we examined the overall foreign body response from initial inflammation to fibrosis capsule formation in detail and introduced various studies to overcome capsular contracture. Secondly, we introduced that the main research approaches are to inhibit fibrosis with anti-inflammatory drugs or antibiotics, to control the topography of the surface of silicone implants, and to administer plasma treatment. Each study examined aspects of the various mechanisms by which capsular contracture could occur, and addressed the effects of inhibiting fibrosis. CONCLUSION: This review introduces various silicone surface modification methods to date and examines their limitations. This review will help identify new directions in inhibiting the fibrosis of silicone implants.

15.
Polymers (Basel) ; 10(7)2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30960697

RESUMO

The number of breast reconstruction surgeries has been increasing due to the increase in mastectomies. Surgical implants (the standard polydimethylsiloxane (PDMS) implants) are widely used to reconstruct breast tissues, however, it can cause problems such as adverse immune reactions, fibrosis, rupture, and additional surgery. Hence, polymeric fillers have recently garnered increasing attention as strong alternatives for breast reconstruction materials. Polymeric fillers offer noninvasive methods of reconstruction, thereby reducing the possible adverse effects and simplifying the treatment. In this study, we synthesized a 2-hydroxylethylmethacrylate (HEMA) and acrylamide (Am) copolymer (Poly(HEMA-Am)) by redox polymerization to be used as a biocompatible filler material for breast reconstruction. The synthesized hydrogel swelled in phosphate buffered saline (PBS) shows an average modulus of 50 Pa, which is a characteristic similar to that of the standard dermal acrylamide filler. To investigate the biocompatibility and cytotoxicity of the Poly(HEMA-Am) hydrogel, we evaluated an in vitro cytotoxicity assay on human fibroblasts (hFBs) and human adipose-derived stem cells (hADSCs) with the hydrogel eluate, and confirmed a cell viability of over 80% of the cell viability with the Poly(HEMA-Am) hydrogel. These results suggest our polymeric hydrogel is a promising filler material in soft tissue augmentation including breast reconstruction.

16.
Acta Biomater ; 76: 56-70, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29908334

RESUMO

In this study, we report a new physicochemical surface on poly(dimethylsiloxane) (PDMS)-based silicone implants in an effort to minimize capsular contracture. Two different surface modification strategies, namely, microtexturing as a physical cue and multilayer coating as a chemical cue, were combined to achieve synergistic effects. The deposition of uniformly sized microparticles onto uncured PDMS surfaces and the subsequent removal after curing generated microtextured surfaces with concave hemisphere micropatterns. The size of the individual micropattern was controlled by the microparticle size. Micropatterns of three different sizes (37.16, 70.22, and 97.64 µm) smaller than 100 µm were produced for potential application to smooth and round-shaped breast implants. The PDMS surface was further chemically modified by layer-by-layer (LbL) deposition of poly-l-lysine and hyaluronic acid. Short-term in vitro experiments demonstrated that all the PDMS samples were cytocompatible. However, lower expression of TGF-ß and α-SMA, the major profibrotic cytokine and myofibroblast marker, respectively, was observed in only multilayer-coated PDMS samples with larger size micropatterns (70.22 and 97.64 µm), thereby confirming the synergistic effects of physical and chemical cues. An in vivo study conducted for 8 weeks after implantation in rats also indicated that PDMS samples with larger size micropatterns and multilayer coating most effectively inhibited capsular contracture based on analyses of tissue inflammation, number of macrophage, fibroblast and myofibroblast, TGF-ß expression, collagen density, and capsule thickness. STATEMENT OF SIGNIFICANCE: Although poly(dimethylsiloxane) (PDMS)-based silicone implants have been widely used for various applications including breast implants, they usually cause typical side effects called as capsular contracture. Prior studies have shown that microtexturing and surface coating could reduce capsular contracture. However, previous methods are limited in their scope for application, and it is difficult to obtain FDA approval because of the large and nonuniform size of the microtexture as well as the use of toxic chemical components. Herein, those issues could be addressed by creating a microtexture of size less than 100 m, with a narrow size distribution and using layer-by-layer deposition of a biocompatible polymer without using any toxic compounds. Furthermore, this is the first attempt to combine microtexture with multilayer coating to obtain synergetic effects in minimizing the capsular contracture.


Assuntos
Implantes de Mama , Materiais Revestidos Biocompatíveis/química , Dimetilpolisiloxanos/química , Implantes Experimentais , Nylons/química , Silício/química , Células 3T3 , Animais , Camundongos , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície
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