Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nat Biomed Eng ; 7(11): 1419-1436, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37749310

RESUMO

Small animals do not replicate the severity of the human foreign-body response (FBR) to implants. Here we show that the FBR can be driven by forces generated at the implant surface that, owing to allometric scaling, increase exponentially with body size. We found that the human FBR is mediated by immune-cell-specific RAC2 mechanotransduction signalling, independently of the chemistry and mechanical properties of the implant, and that a pathological FBR that is human-like at the molecular, cellular and tissue levels can be induced in mice via the application of human-tissue-scale forces through a vibrating silicone implant. FBRs to such elevated extrinsic forces in the mice were also mediated by the activation of Rac2 signalling in a subpopulation of mechanoresponsive myeloid cells, which could be substantially reduced via the pharmacological or genetic inhibition of Rac2. Our findings provide an explanation for the stark differences in FBRs observed in small animals and humans, and have implications for the design and safety of implantable devices.


Assuntos
Reação a Corpo Estranho , Mecanotransdução Celular , Camundongos , Humanos , Animais , Próteses e Implantes , Células Mieloides/patologia , Transdução de Sinais
2.
Front Med (Lausanne) ; 10: 1060758, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36999070

RESUMO

Introduction: According to the American Diabetes Association (ADA), 9-12 million patients suffer from chronic ulceration each year, costing the healthcare system over USD $25 billion annually. There is a significant unmet need for new and efficacious therapies to accelerate closure of non-healing wounds. Nitric Oxide (NO) levels typically increase rapidly after skin injury in the inflammatory phase and gradually diminish as wound healing progresses. The effect of increased NO concentration on promoting re-epithelization and wound closure has yet to be described in the context of diabetic wound healing. Methods: In this study, we investigated the effects of local administration of an NO-releasing gel on excisional wound healing in diabetic mice. The excisional wounds of each mouse received either NO-releasing gel or a control phosphate-buffered saline (PBS)-releasing gel treatment twice daily until complete wound closure. Results: Topical administration of NO-gel significantly accelerated the rate of wound healing as compared with PBS-gel-treated mice during the later stages of healing. The treatment also promoted a more regenerative ECM architecture resulting in shorter, less dense, and more randomly aligned collagen fibers within the healed scars, similar to that of unwounded skin. Wound healing promoting factors fibronectin, TGF-ß1, CD31, and VEGF were significantly elevated in NO vs. PBS-gel-treated wounds. Discussion: The results of this work may have important clinical implications for the management of patients with non-healing wounds.

3.
Plast Reconstr Surg ; 152(4): 637e-645e, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36735824

RESUMO

BACKGROUND: Capsular fibrosis (CF) often occurs around biomedical devices following implantation causing pain, discomfort, and device failure. Breast implantation remains among the most common medical procedures worldwide. Revealing specific genes that drive fibrotic deposition will help us to garner a better understanding of the pathophysiology of this disease and develop different strategies to combat it. METHODS: The authors collected 631 capsules around breast implants and were able to connect clinical baseline characteristics with histopathologic findings. In addition, the authors were able to conduct the first large systematic analysis to identify differentially expressed genes in fibrotic human tissue samples, comparing the lowest form of fibrosis with the most aggravated one. RESULTS: The authors identified 2559 differentially expressed genes on which they performed a knowledge-based network generation and pathway association study to identify putative novel biomarkers for CF. The authors were able to show changes of cellular influx during progression of CF and distinguish several genes as potential clinical biomarkers and drug targets. Among these, matrix metalloproteinase-9 was one of the most up-regulated ( P = 0.006) and is attractive because of its wide detectability. CONCLUSIONS: Matrix metalloproteinase-9 seems to be a potential biomarker to detect capsular fibrosis. It is a measurable indicator that can easily be detected in blood, sputum, and urine. For the diagnosis of fibrosis, this biomarker might be exceedingly beneficial to developing novel screening methods and prophylaxes. CLINICAL RELEVANCE STATEMENT: Discovering biomarkers at the earliest and mildest stages for the diagnosis of fibrosis is clinically important. These results bring new hope for biomarker-based diagnosis for capsular fibrosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, V.


Assuntos
Implantes de Mama , Metaloproteinase 9 da Matriz , Humanos , Metaloproteinase 9 da Matriz/genética , Contratura Capsular em Implantes/etiologia , Implantes de Mama/efeitos adversos , Biomarcadores/análise , Fibrose
4.
Arch Gynecol Obstet ; 307(2): 549-555, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35635619

RESUMO

PURPOSE: Lipofilling has been established as a standard technique for contour enhancement following breast reconstruction. However, there is a paucity in current literature regarding the use of this technique for complete reconstruction of the female breast as an alternative to conventional techniques, such as expander or flap-based procedures. In particular, the influence of pre-operative irradiation for successful reconstruction has rarely been examined in published studies. Here, the authors describe their experience with successful fat injection in pre-radiated breasts in comparison with non-pre-radiated patients. METHODS: In this retrospective study, we examined a total of 95 lipofilling treatments on 26 patients (28 breasts). All of them experienced mastectomy following breast cancer; local breast defects after partial resection of the gland were not included in this study. In total, 47 lipofilling procedures in 12 non-irradiated patients (14 breasts) and 48 procedures in 14 irradiated women (also 14 breasts) were performed. Per session, approximately 297 ± 112 cc of adipose tissue was grafted in group A (no radiotherapy) and approximately 259 ± 93 cc was grafted in group B (radiotherapy). RESULTS: Among the group of women without pre-operative radiation, 71% of breast reconstructions limited to lipofilling only showed constant engraftment of fat tissue with a successful reconstructive result, whereas only 21% of the patients with pre-radiated breasts showed complete reconstruction of the breast with a permanent fat in-growth. CONCLUSION: Preoperative radiotherapy significantly impedes successful completion of breast reconstructions planned only by autologous fat transfer. Patients should be selected individually and carefully for complete breast reconstruction using lipofilling only.


Assuntos
Neoplasias da Mama , Mamoplastia , Feminino , Humanos , Mastectomia/métodos , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Estudos Retrospectivos , Mamoplastia/métodos , Tecido Adiposo
5.
Nat Commun ; 12(1): 5256, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489407

RESUMO

Tissue repair and healing remain among the most complicated processes that occur during postnatal life. Humans and other large organisms heal by forming fibrotic scar tissue with diminished function, while smaller organisms respond with scarless tissue regeneration and functional restoration. Well-established scaling principles reveal that organism size exponentially correlates with peak tissue forces during movement, and evolutionary responses have compensated by strengthening organ-level mechanical properties. How these adaptations may affect tissue injury has not been previously examined in large animals and humans. Here, we show that blocking mechanotransduction signaling through the focal adhesion kinase pathway in large animals significantly accelerates wound healing and enhances regeneration of skin with secondary structures such as hair follicles. In human cells, we demonstrate that mechanical forces shift fibroblasts toward pro-fibrotic phenotypes driven by ERK-YAP activation, leading to myofibroblast differentiation and excessive collagen production. Disruption of mechanical signaling specifically abrogates these responses and instead promotes regenerative fibroblast clusters characterized by AKT-EGR1.


Assuntos
Indóis/farmacologia , Mecanotransdução Celular/fisiologia , Pele/lesões , Sulfonamidas/farmacologia , Cicatrização/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Colágeno/metabolismo , Feminino , Fibroblastos , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/metabolismo , Regeneração Tecidual Guiada , Humanos , Indóis/sangue , Mecanotransdução Celular/efeitos dos fármacos , Análise de Sequência de RNA , Análise de Célula Única , Pele/efeitos dos fármacos , Pele/patologia , Fenômenos Fisiológicos da Pele , Estresse Mecânico , Sulfonamidas/sangue , Suínos , Cicatrização/efeitos dos fármacos
6.
BMC Mol Cell Biol ; 22(1): 25, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941075

RESUMO

BACKGROUND: Capsular fibrosis (CF) is the most common long-term complication in implant-based breast augmentation. It is well accepted that the foreign body response (FBR) instigates the development of fibrotic disease. Our study aims to compare murine and human samples of CF and describe the cellular and extracellular matrix (ECM) composition using scanning and transmission electron microscopy (SEM and TEM). RESULTS: Miniature microtextured silicone breast implants were implanted in mice and subsequently harvested at days 15, 30, and 90 post-operation. Isolated human capsules with the most aggravated form of CF (Baker IV) were harvested post-operation. Both were analyzed with SEM and TEM to assess cellular infiltration and ECM structure. An architectural shift of collagen fiber arrangement from unidirectional to multidirectional was observed at day 90 when compared to days 15 and 30. Fibrosis was observed with an increase of histiocytic infiltration. Moreover, bacterial accumulation was seen around silicone fragments. These findings were common in both murine and human capsules. CONCLUSIONS: This murine model accurately recapitulates CF found in humans and can be utilized for future research on cellular invasion in capsular fibrosis. This descriptive study helps to gain a better understanding of cellular mechanisms involved in the FBR. Increases of ECM and cellularity were observed over time with SEM and TEM analysis.


Assuntos
Implantes de Mama , Mama/ultraestrutura , Reação a Corpo Estranho/patologia , Animais , Mama/patologia , Feminino , Fibrose , Reação a Corpo Estranho/etiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
7.
Plast Reconstr Surg Glob Open ; 8(9): e3136, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33133975

RESUMO

Hyperbaric oxygen therapy (HBOT) serves as "primary" or "adjunctive" therapy in a wide range of pathologies. It is considered the mainstay of management for potentially life-threatening conditions such as carbon monoxide poisoning, decompression illness, and gas embolisms. Moreover, HBOT has been utilized for decades as an adjunctive therapy in a variety of medical disciplines, including chronic wounds, which affect approximately 6.5 million Americans annually. In general, chronic wounds are characterized by hypoxia, impaired angiogenesis, and prolonged inflammation, all of which may theoretically be ameliorated by HBOT. Nonetheless, the cellular, biochemical, and physiological mechanisms by which HBOT achieves beneficial results in chronic wounds are not fully understood, and there remains significant skepticism regarding its efficacy. This review article provides a comprehensive overview of HBOT, and discusses its history, mechanisms of action, and its implications in management of chronic wounds. In particular, we discuss the current evidence regarding the use of HBOT in diabetic foot ulcers, while digging deeply into the roots of controversy surrounding its efficacy. We discuss how the paucity of high-quality research is a tremendous challenge, and offer future direction to address existing obstacles.

8.
J Clin Med ; 9(7)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668782

RESUMO

Breast cancer is among the most commonly diagnosed cancers in the world, affecting one in eight women in their lifetimes. The disease places a substantial burden on healthcare systems in developed countries and often requires surgical correction. In spite of this, much of the breast cancer pathophysiology remains unknown, allowing for the cancer to develop to later stages prior to detection. Many women undergo reduction mammaplasties (RM) to adjust breast size, with over 500,000 operations being performed annually. Tissue samples from such procedures have drawn interest recently, with studies attempting to garner a better understanding of breast cancer's development. A number of samples have revealed nascent cancer developments that were previously undetected and unexpected. Investigating these so-called "occult" findings of cancer in otherwise healthy patients may provide further insight regarding risk factors and countermeasures. Here, we detail occult findings of cancer in reduction mammaplasty samples provided from a cohort of over 5000 patients from 16 different institutions in Europe. Although the majority of our resected breast tissue specimens were benign, our findings indicate that there is a continued need for histopathological examination. As a result, our study suggests that preoperative imaging should be routinely performed in patients scheduled for RM, especially those with risk factors of breast cancer, to identify and enable a primary oncologic approach.

9.
Mol Ther ; 28(9): 2007-2022, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32531238

RESUMO

Intravenous infusion of mesenchymal stromal cells (MSCs) is thought to be a viable treatment for numerous disorders. Although the intrinsic immunosuppressive ability of MSCs has been credited for this therapeutic effect, their exact impact on endogenous tissue-resident cells following delivery has not been clearly characterized. Moreover, multiple studies have reported pulmonary sequestration of MSCs upon intravenous delivery. Despite substantial efforts to improve MSC homing, it remains unclear whether MSC migration to the site of injury is necessary to achieve a therapeutic effect. Using a murine excisional wound healing model, we offer an explanation of how sequestered MSCs improve healing through their systemic impact on macrophage subpopulations. We demonstrate that infusion of MSCs leads to pulmonary entrapment followed by rapid clearance, but also significantly accelerates wound closure. Using single-cell RNA sequencing of the wound, we show that following MSC delivery, innate immune cells, particularly macrophages, exhibit distinctive transcriptional changes. We identify the appearance of a pro-angiogenic CD9+ macrophage subpopulation, whose induction is mediated by several proteins secreted by MSCs, including COL6A1, PRG4, and TGFB3. Our findings suggest that MSCs do not need to act locally to induce broad changes in the immune system and ultimately treat disease.


Assuntos
Macrófagos Alveolares/imunologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Transcrição Gênica/genética , Cicatrização/imunologia , Animais , Modelos Animais de Doenças , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Infusões Intravenosas/métodos , Macrófagos Alveolares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7 , RNA-Seq/métodos , Análise de Célula Única/métodos , Tetraspanina 29/metabolismo
10.
J Clin Med ; 9(5)2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403382

RESUMO

Skin injury is a common occurrence and mechanical forces are known to significantly impact the biological processes of skin regeneration and wound healing. Immediately following the disruption of the skin, the process of wound healing begins, bringing together numerous cell types to collaborate in several sequential phases. These cells produce a multitude of molecules and initiate multiple signaling pathways that are associated with skin disorders and abnormal wound healing, including hypertrophic scars, keloids, and chronic wounds. Studies have shown that mechanical forces can alter the microenvironment of a healing wound, causing changes in cellular function, motility, and signaling. A better understanding of the mechanobiology of cells in the skin is essential in the development of efficacious therapeutics to reduce skin disorders, normalize abnormal wound healing, and minimize scar formation.

11.
J Clin Med ; 9(5)2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344893

RESUMO

BACKGROUND: Breast-implant-associated anaplastic large cell lymphoma (BI-ALCL) and primary breast ALCL are rare extranodal manifestations of non-Hodgkin lymphoma. The rarity of both diseases, along with unreleased sales data on breast implants and constant updates of classification systems impede the calculation of an exact incidence. METHODS: The database of the Tumor Center Regensburg in Bavaria was searched for patients with CD30-positive and ALK-negative anaplastic large cell lymphoma between 2002 and 2018. These lymphomas were identified by the ICD-O-3 morphology code "97023" and were cross-checked by searching the diagnosis by name the and ICD-10 code C84.7. Furthermore, we tried to calculate the incidence rates and corresponding 95% confidence intervals, standardized to 1,000,000 implant years of breast-implant-associated anaplastic large cell lymphoma and primary breast anaplastic large cell lymphoma. RESULTS: Twelve ALK-negative and CD30-positive anaplastic large cell lymphomas were identified out of 170,405 malignancies. No case was found within the breast tissue and none of the patients had a previous history of breast implant placement. In five cases, lymph node involvement in close proximity to the breast was observed. CONCLUSION: We found a low incidence of anaplastic large cell lymphoma and no association to breast implants in these patients. A review of the current literature revealed inconsistent use of classification systems for anaplastic large cell lymphomas and potential overestimation of cases.

12.
Plast Reconstr Surg Glob Open ; 8(1): e2590, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32095400

RESUMO

The use of systemic prophylactic antibiotics to reduce surgical-site infection in esthetic breast surgery remains controversial, although the majority of surgeons prefer to utilize antibiotics to prevent infection. Nonetheless, postoperative acute and subclinical infection and capsular fibrosis are among the most common complications following implant-based breast reconstruction. After esthetic breast augmentation, up to 2.9% of women develop infection, with an incidence rate of 1.7% for acute infections and 0.8% for late infections. After postmastectomy reconstruction (secondary reconstruction), the rates are even higher. The microorganisms seen in acute infections are Gram-positive, whereas subclinical late infections involving microorganisms are typically Gram-negative and from normal skin flora with low virulence. In primary implantation, a weight-based dosing of cefazolin is adequate, an extra duration of antibiotic cover does not provide further reduction in superficial or periprosthetic infections. Clindamycin and vancomycin are recommended alternative for patients with ß-lactam allergies. The spectrum of microorganism found in late infections varies (Gram-positive and Gram-negative), and the antibiotic prophylaxis (fluoroquinolones) should be extended by vancomycin and according to the antibiogram when replacing implants and in secondary breast reconstruction, to target microorganisms associated with capsular contracture. All preoperative antibiotics should be administered <60 minutes before incision to guarantee high serum levels during surgical procedure.

13.
Adv Wound Care (New Rochelle) ; 9(3): 111-126, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31993253

RESUMO

Significance: The skin undergoes an inevitable degeneration as an individual ages. As intrinsic and extrinsic factors degrade the structural integrity of the skin, it experiences a critical loss of function and homeostatic stability. Thus, aged skin becomes increasingly susceptible to injury and displays a prolonged healing process. Recent Advances: Several studies have found significant differences during wound healing between younger and older individuals. The hypoxia-inducible factor 1-alpha (HIF-1α) signaling pathway has recently been identified as a major player in wound healing. Hypoxia-inducible factors (HIFs) are pleiotropic key regulators of oxygen homeostasis. HIF-1α is essential to neovascularization through its regulation of cytokines, such as SDF-1α (stromal cell-derived factor 1-alpha) and has been shown to upregulate the expression of genes important for a hypoxic response. Prolyl hydroxylase domain proteins (PHDs) and factor inhibiting HIF effectively block HIF-1α signaling in normoxia through hydroxylation, preventing the signaling cascade from activating, leading to impaired tissue survival. Critical Issues: Aged wounds are a major clinical burden, resisting modern treatment and costing millions in health care each year. At the molecular level, aging has been shown to interfere with PHD regulation, which in turn prevents HIF-1α from activating gene expression, ultimately leading to impaired healing. Other studies have identified loss of function in cells during aging, impeding processes such as angiogenesis. Future Directions: An improved understanding of the regulation of molecular mediators, such as HIF-1α and PHD, will allow for manipulation of the various factors underlying delayed wound healing in the aged. The findings highlighted in this may facilitate the development of potential therapeutic approaches involved in the alteration of cellular dynamics and aging.


Assuntos
Envelhecimento/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Neovascularização Patológica/metabolismo , Transdução de Sinais , Pele/efeitos dos fármacos , Hipóxia Celular , Proliferação de Células , Humanos , Pele/enzimologia , Pele/patologia , Cicatrização
14.
Adv Wound Care (New Rochelle) ; 8(4): 168-176, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31832273

RESUMO

Significance: Hypertrophic scars, keloids, and burn injuries of the skin have a significant impact on patients' lives and impact the health care system tremendously. Treating skin wounds and lesions can be challenging, with a variety of choices available for treatment. Scar and burn managements range from invasive, surgical options such as scar excision to less invasive, nonsurgical alternatives such as laser therapy or topical drug application. Recent Advances: Laser treatment has become increasingly popular, with a growing body of research supporting its use for scars and burns. Numerous methods are available for the treatment of these skin diseases, including different nonsurgical laser therapies. Critical Issues: To date, the optimal treatment method for scars, keloids, and burn injuries of the skin has not yet been established, although it is an area of increasing clinical concern. Future Directions: This review provides an updated summary of the treatment of scars and burn wounds of the skin using different laser treatments, including the most recent technologies. It addresses their indications, mechanisms of action, differences, efficacies, and complications.

16.
Clin Hemorheol Microcirc ; 73(1): 43-51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31561346

RESUMO

BACKGROUND: To overcome the compromised wound healing in radiation induced chronic wounds platelet-rich plasma (PRP), as therapeutic agent, is current subject of studies. PRP is associated with pro-angiogenic effects. Nevertheless, effects of platelet-rich plasma in cutaneous wound healing processes are poorly understood so far. METHODS: In this study, the migration of endothelial cells, fibroblasts and keratinocytes in conjunction with platelet-rich plasma treatment is investigated in the context of radiation effects. Additionally, cell proliferation and viability after external radiation was analyzed regarding treatment by platelet-rich plasma. RESULTS: All cell cultures showed a trend towards decreasing proliferation and viability after irradiation irrespective of PRP. Upon PRP treatment, irradiated fibroblasts as well as endothelial cells showed an enhanced proliferation whereas proliferation and viability of keratinocytes was reduced after PRP treatment. Scratch assays support the positive effect of PRP on fibroblast and endothelial cell migration, whereas a negative effect on keratinocytes was observed after PRP treatment. CONCLUSIONS: The present study documents both deleterious effects of external radiation as well as the protective effect of PRP. In summary, increased viability, proliferation and migration are indeed a consequence of the pro-proliferative effect exerted by PRP. Therefore, treatment with PRP products might be useful in the management of chronic radiogenic wounds.


Assuntos
Movimento Celular/imunologia , Células Endoteliais/efeitos da radiação , Plasma Rico em Plaquetas/imunologia , Humanos
17.
Clin Hemorheol Microcirc ; 70(2): 191-200, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710686

RESUMO

BACKGROUND: Implant-based breast augmentation is one of the most frequently performed operations in plastic surgery worldwide, for aesthetic and reconstructive reasons. Capsular fibrosis is the most common long-term foreign body response after breast implant augmentation. OBJECTIVE: To compare the occurrence of capsular contracture in aesthetic and reconstructive-cancer patients, including those patients who received radiotherapy prior to breast reconstruction with implants. METHODS: We conducted a retrospective evaluation of 319 patients who underwent breast implant revision between Jan 2000 and Oct 2016. The patient group was comprised of 175 reconstructive-cancer patients and 144 patients who underwent operation for aesthetic reasons. The occurrence of capsular fibrosis, other complications and the time-period between implantation of breast implants and revision surgery (TP) was analyzed. RESULTS: For all 319 patients the mean TP was 7.9 years (7.86±0.45). The most common complication in all revisions was capsular fibrosis (65.1% of all revisions). In aesthetic patients with capsular fibrosis the mean TP was 11.9 years (11.89±0.95, p < 0.001). This mean TP was significantly higher than the mean TP of 6.1 years (6.13±0.56, p < 0.001) in breast cancer patients with capsular fibrosis. Preoperatively irradiated cancer patients had a mean TP of 6.2 years (6.17±0.95), compared to a mean TP of 5.1 years (5.07±0.19, p = 0.051) in non-irradiated cancer patients, which was not significantly different. CONCLUSIONS: We found that aesthetic patients exhibit a significantly higher mean TP compared to breast cancer patients, suggesting that reconstructive-cancer patients in general develop capsular fibrosis earlier. Despite the literature, we did not find a significant influence of preoperative radiotherapy on the occurrence of capsular fibrosis in reconstructive-cancer patients. Further clinical studies need to be conducted to identify methods to decrease the risk of developing capsular fibrosis.


Assuntos
Implante Mamário/efeitos adversos , Neoplasias da Mama/complicações , Estética , Mamoplastia/efeitos adversos , Adulto , Implante Mamário/métodos , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mamoplastia/métodos , Estudos Retrospectivos
18.
Clin Hemorheol Microcirc ; 66(1): 47-55, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28269759

RESUMO

BACKGROUND: Autologous fat grafts and adipose-derived stem cells (ASCs) can be used to treat soft tissue defects. However, the results are inconsistent and sometimes comprise tissue resorption and necrosis. This might be due to insufficient vascularization. Platelet-rich plasma (PRP) is a source of concentrated autologous platelets. The growth factors and cytokines released by platelets can facilitate angiogenesis. The simultaneous use of PRP might improve the regeneration potential of fat grafts. The optimal ratio has yet to be elucidated. A byproduct of PRP preparation is platelet-poor plasma (PPP). OBJECTIVE: In this study we investigated the influence of different concentrations of PRP on the vitality and differentiation of ASCs. METHODS: We processed whole blood with the Arthrex Angel centrifuge and isolated ASCs from the same donor. We tested the effects of different PRP and PPP concentrations on the vitality using resazurin assays and the differentiation of ASCs using oil-red staining. RESULTS: Both cell vitality and adipogenic differentiation increase to a concentration of 10% to 20% PRP. With a PRP concentration of 30% cell vitality and differentiation decrease. CONCLUSIONS: Both PRP and PPP can be used to expand ASCs without xenogeneic additives in cell culture. A PRP concentration above 20% has inhibitory effects.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Plaquetas/metabolismo , Plasma Rico em Plaquetas/metabolismo , Células-Tronco/metabolismo , Engenharia Tecidual/métodos , Adipócitos/citologia , Tecido Adiposo/citologia , Diferenciação Celular , Humanos , Células-Tronco/citologia
19.
Clin Hemorheol Microcirc ; 63(4): 439-449, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27314443

RESUMO

AIM: To identify a possible connection between anaplastic large cell lymphoma and different types of breast implants. METHODS: We conducted a retrospective evaluation of 296 breast tissues of 227 women with different breast implant types undergoing surgical revision or explantation between January 2000 and June 2015. Histological and selected immunohistochemical analyses of CD30-&ALK-1-markers of the breast capsules were performed. RESULTS: The womens' average age was 42.91±12.66 years (median: 43.83 years) during implantation and 51.40±11.40 years (median: 52.37 years) during revision or explantation of the implants. Average implant residing time was 8.49±8.90 years (median: 5.83 years). In 51% implantation was for reconstructive, in 48% for aesthetic reasons, in 1% for other reasons. At 59% the main reason for explantation or removal was capsular fibrosis (n = 173). In 296 breast capsules we could not find pathological lymphoma cells according to ALCL, retrospectively. CONCLUSION: In our study we detected high incidences of various cells in relationship to the implant's type and residing time, which will be published in further articles. We could not find ALCL-cells in breast capsules of explanted or revised breast implants during 2000-2015, retrospectively.There should be a heightened awareness of a possible relationship between the development of cancer and breast implants. To date there are case reports about a possible association between the development of ALCL and breast implants. The number of cases are few and our knowledge of the pathogenesis is little. Further investigation is needed to understand the possible link between breast implants and ALCL found in the breast.


Assuntos
Implantes de Mama/efeitos adversos , Linfoma Anaplásico de Células Grandes/complicações , Adulto , Feminino , Humanos , Linfoma Anaplásico de Células Grandes/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Clin Hemorheol Microcirc ; 61(4): 645-56, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26444595

RESUMO

AIM: To investigate whether there are fundamental sonographic and elastographic criteria to precisely assess different surfaces and fillings of idle breast implants and to determine their most distinctive parameters. This was a comparative study of different unused breast implant materials, neighter in animals nor in humans. This knowledge should be transferred in vivo to develop an objective measurement tool. METHODS: Nine idle breast implants-silicone and polyurethane (PU)-were examined in an experimental study by using ultrasound B-mode with tissue harmonic imaging (THI), speckle reduction imaging (SRI, level 0-4), cross-beam (CB, low, medium, high), photopic and the colour coded ultrasound-strain elastography with a multifrequency probe (9-15 MHz).Using a standardised protocol the implants' centre as well as the edge were analysed by one experienced examiner. Two independent readers performed analysis and evaluation. For image interpretation a score was created (score 0:inadequate image, score 5:best image quality). RESULTS: The highest score result for the centre was achieved by using ultrasound with B-mode in addition with CB level medium, SRI level 2, THI and photopic (mean:3.22±SD:1.56), but without any statistic significant difference (t-value = 0.71). With elastography the implants' edge in general was represented without disruptive artefacts (3.89±0.60) with statistic significant difference (t-value = 5.29). Implants filled with inner cohesive silicone gel II° showed best imaging conditions for their centre via ultrasound (5±0) as well as for their edge via elastography (4.50±0.71). CONCLUSION: Ultrasound-strain elastography and high resolution ultrasound represent a valuable measurement tool to evaluate different properties of idle breast implants. These modified ultrasound examinations could be an additional help for clinical investigations and be correlated with Baker's Classification.


Assuntos
Implantes de Mama , Neoplasias da Mama/radioterapia , Técnicas de Imagem por Elasticidade/métodos , Ultrassonografia Mamária/métodos , Feminino , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...