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1.
Med Sci (Basel) ; 11(1)2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810479

RESUMO

BACKGROUND: Increased lifespan and the improvement of medical treatment have given rise to research in reconstructive procedures in elderly patients. Higher postoperative complication rates, longer rehabilitation, and surgical difficulties remain a problem in the elderly. We asked whether a free flap in elderly patients is an indication or a contraindication and performed a retrospective, monocentric study. METHODS: Patients were divided into two groups (YOUNG 0-59 years; OLD > 60 years). The endpoint was the survival of flaps and their dependence on patient- and surgery-specific parameters using multivariate analysis. RESULTS: A total of 110 patients (OLD n = 59) underwent 129 flaps. The chance of flap loss increased as soon as two flaps were performed in one surgery. Anterior lateral thigh flaps had the highest chance for flap survival. Compared with the lower extremity, the head/neck/trunk group had a significantly increased chance of flap loss. There was a significant increase in the odds of flap loss in linear relation to the administration of erythrocyte concentrates. CONCLUSION: The results confirm that free flap surgery can be indicated as a safe method for the elderly. Perioperative parameters such as two flaps in one surgery and transfusion regimens must be considered as risk factors for flap loss.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Humanos , Idoso , Estudos Retrospectivos , Resultado do Tratamento , Contraindicações
2.
Bioengineering (Basel) ; 9(7)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35877349

RESUMO

Artificial tissue substitutes are of great interest for the reconstruction of destroyed and non-functional skin or bone tissue due to its scarcity. Biomaterials used as scaffolds for tissue regeneration are non-vascularized synthetic tissues and often based on polymers, which need ingrowth of new blood vessels to ensure nutrition and metabolism. This review summarizes previous approaches and highlights advances in vascularization strategies after implantation of surface-modified biomaterials for skin and bone tissue regeneration. The efficient integration of biomaterial, bioactive coating with endogenous degradable matrix proteins, physiochemical modifications, or surface geometry changes represents promising approaches. The results show that the induction of angiogenesis in the implant site as well as the vascularization of biomaterials can be influenced by specific surface modifications. The neovascularization of a biomaterial can be supported by the application of pro-angiogenic substances as well as by biomimetic surface coatings and physical or chemical surface activations. Furthermore, it was confirmed that the geometric properties of the three-dimensional biomaterial matrix play a central role, as they guide or even enable the ingrowth of blood vessels into a biomaterial.

3.
Innov Surg Sci ; 6(3): 97-104, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35224177

RESUMO

OBJECTIVES: Autologous transplants are still the means of choice for bypass surgery. In addition to good tolerability, there is a reduced thrombogenicity and fewer neointima hyperplasia compared to artificial materials. However, since viable transplants are limited, attempts are being made to improve existing artificial vascular prosthesis material. Next to the reduction of thrombogenicity, a rapid endothelialization of the vascular graft should reduce intimal hyperplasia and thus prevent stenoses. The effect of newly developed silicon oxide coatings on the growth of endothelial cells was therefore the goal of this work in a cell culture study. METHODS: A woven, uncoated polyethylene terephthalate (PET) vessel prosthesis was used. The coating process was carried out in a low-pressure plasma reactor in a multi-step process. After preparation of the vacuum chamber hexamethyldisiloxane (HDMSO) with oxygen was evaporated using argon plasma. By this an approx. 1 nm thin adhesion promoter layer was separated from plasma and HMDSO. The silicone oxide barrier layer was applied to the PET vessel samples. The carbon content of the layer could be selectively altered by changing the HMDSO oxygen flow ratio, resulting in coatings of 100 nm, 500 nm, and 1,000 nm. In addition, two different oxygen-to-HMDSO ratios were used. To achieve a carbon coating as low as possible, the ratio was set to 200:1. A carbon-rich layer was obtained with the 1:1 setting. The various coatings were then examined for their surface texture by scanning electron microscopy (SEM) as well as by cell culture experiments for cell viability and growth using EA.hy 926 cells. RESULTS: SEM showed no changes in the surface morphology; however a layer thickness of 1,000 nm showed peeled off coating areas. Alamar blue assays showed a significantly higher metabolic activity (p=0.026) for the coating 500 nm, ratio 200:1 compared to untreated control samples and a significantly lower metabolic activity (p=0.037) of the coating 500 nm, ratio 1:1 compared to the coating 500 nm, ratio 200:1. This underlines the apparent tendency of the 1:1 coating to inhibit the metabolic activity of the cells, while the 200:1 coating increases the activity. Fluorescence microscopy after calcein acetoxymethyl ester (AM) staining showed no significant difference between the different coatings and the uncoated PET material. However, a tendency of the increased surface growth on the coating 500 nm, ratio 200:1, is shown. The coatings with the ratio 1:1 tend to be less densely covered. CONCLUSIONS: The results of this work indicate a great potential in the silicon coating of vascular prosthesis material. The plasma coating can be carried out easy and gently. Cell culture experiments demonstrated a tendency towards better growth of the cells on the 200:1 ratio coating and a poorer growth on the carbon-rich coating 1:1 compared to the uncoated material. The coating with silicon oxide with a thickness of 500 nm and an oxygen-HMDSO ratio of 200:1, a particularly low-carbon layer, appears to be a coating, which should therefore be further investigated for its effects on thrombogenicity and intimal hyperplasia.

4.
Handchir Mikrochir Plast Chir ; 53(4): 426-436, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-33086393

RESUMO

BACKGROUND: Facelift is now the fourth most common aesthetic procedure in men. Facial ageing is very different in men and women. Therefore, individual techniques are used since a uniform concept for the surgical facelift in men does not exist. This study aims to evaluate a gender-specific facelift concept especially developed for men. MATERIAL AND METHODS: Women and men (n = 10 each) were subjected to a three-dimensional face scan and a subsequent simulation of a V-shaped lift vector (standard lift) and a new facelift concept especially for men in a double T shape (male lift). In an online survey with 262 participants, the simulated as well as the unchanged images were presented and the attributes masculinity, femininity, attractiveness and youthfulness were queried. Statistical models were used to identify attributes of lifting as well as other factors and differences between the simulations. RESULTS: Facelift changes are generally associated with a significant improvement in the attributes of youthfulness and attractiveness compared with unchanged control faces. As expected, a male lift leads to masculinisation, while a standard lift leads to feminisation, regardless of the sex of the subjects. The male lift led to higher values for the attribute attractiveness in male subjects, as did the standard lift in female subjects. The standard lift developed for women is indeed more suitable for women and is associated with a significantly higher probability for the attribute youthfulness, whereas this is not the case in the newly introduced male lift concept. CONCLUSION: The new facelift concept for male patients is significantly associated with masculinity and attractiveness, while the standard lift suitable for women is associated with significantly higher evaluations of femininity and youthfulness. The results of the SIMALIFT study are the first evidence of the need for a more differentiated, gender-specific approach to facelifting.


Assuntos
Ritidoplastia , Idoso , Estética , Feminino , Feminilidade , Humanos , Masculino , Masculinidade , Percepção
5.
Eur Surg Res ; 59(3-4): 232-241, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30244254

RESUMO

BACKGROUND: In response to tissue damage, angiogenesis is an extremely dynamic process that is finely regulated by signals from cells, the surrounding extracellular matrix (ECM), and derived mediators. As the only process, angiogenesis remains of decisive importance in the context of the entire wound healing process and is subject to constant change. The dissolution of the endothelial basement membrane, the migration of endothelial cells, and the development of new capillary vessels during wound healing depend not only on the cells and cytokines present, but also on the production and organization of ECM components in the immediate wound. SUMMARY: Angiogenesis in wound healing can be divided into two main phases. During the pro-angiogenic phase at the beginning of wound healing, excessive neo-formation of blood vessels, some of which are poorly differentiated, occurs, which restore blood flow and thus nutritive perfusion as quickly as possible. This is followed by an anti-angiogenic phase in which the initially established vascular network undergoes a maturing process, which, however, is accompanied by a significant reduction in the number of vessels. Key Messages: Although many mechanisms and specific cell functions in wound healing have already been described, many underlying pathophysiological processes remain unknown. Because angiogenesis and its maturation is a very fast but also very long-lasting process, the understanding of the underlying mechanisms is of crucial importance. This article will give an overview of the current understanding and controversy in this sub-step of wound healing.


Assuntos
Neovascularização Fisiológica/fisiologia , Cicatrização/fisiologia , Matriz Extracelular/metabolismo , Humanos , Microcirculação
6.
Ultrasound Med Biol ; 44(7): 1563-1568, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29699718

RESUMO

The Diver Box is designed to prevent impedance differences, energy loss or damage to neighboring structures caused by the use of shock waves with application gels. The Diver Box is an acrylic glass container filled with tempered water and includes a coupling membrane to prevent the impedance jump from air to water and to avoid the continuous propagation of shock waves into the tissue, maintaining wave dynamics. Different modes of extracorporeal shock waves can be applied to a mouse skin wound without energy loss and protected from harmful phase-reversed waves. Macroscopic changes were seen in only 5% to 12% of tested specimens. Hazardous phase reversal, back reflection and mechanical tissue damage can be avoided by use of the Diver Box, ensuring standardized extracorporeal shock wave application.


Assuntos
Géis , Ondas de Choque de Alta Energia/uso terapêutico , Dermatopatias/terapia , Pele/lesões , Animais , Modelos Animais de Doenças , Feminino , Vidro , Camundongos , Camundongos Endogâmicos BALB C , Água
7.
Biomed Tech (Berl) ; 63(4): 421-426, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28640750

RESUMO

The most common complication after implantation of foreign material is infection, leading to implant failure and severe patient discomfort. Smoldering-infections proceed inapparently and might not get verified by radiological diagnostics. Early identification of this type of infection might significantly reduce the rate of complications. Therefore, we manufactured a microsensor strip in a hybrid of thin-film and laminate technology in a wafer-level process. It comprises electrochemical, amperometric microsensors for glucose, oxygen and lactate as well as an integrated reference electrode. Microsensors have been implanted in the mouse dorsal skin fold chamber, which got inoculated with a human-pathogen bacterial strain. A selective signal could be measured for all parameters and time points. The infection led to measurable changes of the wound environment as given by a decrease of the oxygen- as well as the glucose-concentration while the lactate concentration increased markedly over time. The given results in this study are the first hints on a promising new tool and should therefore be interpreted as a proof of the principle to show the functionality of the microsensors in an in vivo setting. These microsensors could be used to monitor smoldering infections of implantable foreign materials reducing foreign implant associated complications.


Assuntos
Controle de Infecções/normas , Próteses e Implantes , Animais , Humanos , Camundongos , Monitorização Fisiológica , Projetos Piloto
8.
Innov Surg Sci ; 2(1): 23-25, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31579730

RESUMO

A 46-year-old man presented with clinical signs of nerve compression syndrome of his right ulnar nerve as confirmed by nerve conduction studies. Unexpectedly, clinical examination and magnetic resonance imaging (MRI) revealed a subcutaneous tumor of 5×2 cm above the ulnar groove. Surgical exploration and histopathology of biopsies demonstrated the nerve distended and entrapped into an eosinophilic, inflammatory tissue. This rare condition is consistent with localized eosinophilic fasciitis, with no systemic manifestations. There are reports of isolated forearm versions of the disease. However, none occurred with the entrapment of a peripheral nerve appearing as a peripheral nerve tumor, yet. Consequentially, the presented patient would not have benefitted from further surgical neurolysis or tumor debulking, as eosinophilic fasciitis is an inflammatory and systemic disease. The patient's symptoms decreased spontaneously after 4 weeks of postsurgical treatment, including nonsteroidal anti-inflammatory drugs (NSAIDs). Altogether, this case proved the necessity to regard even rare diseases as a potential cause of entrapment of peripheral nerves. This should lead surgeons to critical, differential diagnostic thinking and suggest that systemic diseases may be encountered during surgery due to their capability to mimic peripheral nerve tumors.

9.
Eur Surg Res ; 58(1-2): 81-94, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27974711

RESUMO

BACKGROUND: The integrity of healthy skin plays a crucial role in maintaining physiological homeostasis of the human body. The skin is the largest organ system of the body. As such, it plays pivotal roles in the protection against mechanical forces and infections, fluid imbalance, and thermal dysregulation. At the same time, it allows for flexibility to enable joint function in some areas of the body and more rigid fixation to hinder shifting of the palm or foot sole. Many instances lead to inadequate wound healing which necessitates medical intervention. Chronic conditions such as diabetes mellitus or peripheral vascular disease can lead to impaired wound healing. Acute trauma such as degloving or large-scale thermal injuries are followed by a loss of skin organ function rendering the organism vulnerable to infections, thermal dysregulation, and fluid loss. METHODS: For this update article, we have reviewed the actual literature on skin wound healing purposes focusing on the main phases of wound healing, i.e., inflammation, proliferation, epithelialization, angiogenesis, remodeling, and scarring. RESULTS: The reader will get briefed on new insights and up-to-date concepts in skin wound healing. The macrophage as a key player in the inflammatory phase will be highlighted. During the epithelialization process, we will present the different concepts of how the wound will get closed, e.g., leapfrogging, lamellipodial crawling, shuffling, and the stem cell niche. The neovascularization represents an essential component in wound healing due to its fundamental impact from the very beginning after skin injury until the end of the wound remodeling. Here, the distinct pattern of the neovascularization process and the special new functions of the pericyte will be underscored. At the end, this update will present 3 topics of high interest in skin wound healing issues, dealing with scarring, tissue engineering, and plasma application. CONCLUSION: Although wound healing mechanisms and specific cell functions in wound repair have been delineated in part, many underlying pathophysiological processes are still unknown. The purpose of the following update on skin wound healing is to focus on the different phases and to brief the reader on the current knowledge and new insights. Skin wound healing is a complex process, which is dependent on many cell types and mediators interacting in a highly sophisticated temporal sequence. Although some interactions during the healing process are crucial, redundancy is high and other cells or mediators can adopt functions or signaling without major complications.


Assuntos
Reepitelização , Cicatrização , Animais , Coagulação com Plasma de Argônio , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos , Cicatriz , Humanos , Inflamação , Neovascularização Fisiológica , Engenharia Tecidual
10.
Z Evid Fortbild Qual Gesundhwes ; 115-116: 71-77, 2016 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-27837962

RESUMO

OBJECTIVE: The postdoctoral medical lecture qualification (Habilitation) represents the highest academic qualification in Germany, which is successfully completed by approximately 850 candidates in medicine and health sciences per year. However, there is only a limited number of respective academic positions available. In addition, structures in education and society have changed over the last years, challenging the importance of this specific German qualification. The aim of this study was to elicit the opinions of members of German habilitation committees concerning the requirements, processes and the overall importance of the postdoctoral medical lecture qualification. Furthermore we wanted to evaluate potential needs for reforms. METHODS: The online survey was conducted asking for biographic parameters, subjective ratings and potential needs for reforms concerning the postdoctoral medical lecture qualification (PLQ). RESULTS: The PLQ was rated high in significance by 71.3 % of the committee members. According to the medical understanding of the Humboldt triad (research, teaching, patient care), research (94.3 %) and teaching (89.7 %) have been rated as the most important requirements for a PLQ. Asked for the motivation to undertake a PLQ, 91.0 % of the members gave the joy of doing research, 78.2 % the joy of teaching and 65.5 % better career prospects perspectives as their reason. The recognition of a Ph.D. degree as being equivalent to a German PQL was clearly rejected by the survey respondents (58.6 %: no equivalence). The majority is against the abolition of the German PLQ. However, there is a definite desire for reform, preferably concerning internal obstacles such as the dependence on full professors, more transparency in the PLQ process, but also the demand for a federal standard PLQ regulation. CONCLUSION: From the committee members' point of view the German PLQ has still a role to play and, despite controversy, is still regarded as a timely qualification. However, there is clear-cut evidence for local, national and international reforms in order to create equality of opportunity for the candidates and to open up suitable career options.


Assuntos
Currículo , Educação de Pós-Graduação em Medicina , Alemanha , Humanos , Pesquisa
11.
BMC Cancer ; 13: 490, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24144362

RESUMO

BACKGROUND: Chemotherapy for soft tissue sarcomas remains unsatisfactory due to their low chemosensitivity. Even the first line chemotherapeutic agent doxorubicin only yields a response rate of 18-29%. The antibiotic salinomycin, a potassium ionophore, has recently been shown to be a potent compound to deplete chemoresistant cells like cancer stem like cells (CSC) in adenocarcinomas. Here, we evaluated the effect of salinomycin on sarcoma cell lines, whereby salinomycin mono- and combination treatment with doxorubicin regimens were analyzed. METHODS: To evaluate the effect of salinomycin on fibrosarcoma, rhabdomyosarcoma and liposarcoma cell lines, cells were drug exposed in single and combined treatments, respectively. The effects of the corresponding treatments were monitored by cell viability assays, cell cycle analysis, caspase 3/7 and 9 activity assays. Further we analyzed NF-κB activity; p53, p21 and PUMA transcription levels, together with p53 expression and serine 15 phosphorylation. RESULTS: The combination of salinomycin with doxorubicin enhanced caspase activation and increased the sub-G1 fraction. The combined treatment yielded higher NF-κB activity, and p53, p21 and PUMA transcription, whereas the salinomycin monotreatment did not cause any significant changes. CONCLUSIONS: Salinomycin increases the chemosensitivity of sarcoma cell lines - even at sub-lethal concentrations - to the cytostatic drug doxorubicin. These findings support a strategy to decrease the doxorubicin concentration in combination with salinomycin in order to reduce toxic side effects.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Piranos/farmacologia , Sarcoma , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/toxicidade , Sinergismo Farmacológico , Humanos , Piranos/toxicidade , Sarcoma/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
12.
J Burn Care Res ; 34(3): e195-200, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22955161

RESUMO

Psoralen-ultraviolet A (PUVA) chemotherapy is an established treatment for certain skin diseases. Burn injury is a serious complication of PUVA therapy. Reports regarding this complication are limited. The aim of this study was to determine the management and outcome of severe PUVA burns. A retrospective review of the medical records of PUVA burns treated at our burn center from 2000 to 2010 was conducted. Data collected included age, sex, condition, mode of PUVA, site, surface area involved, depth of burns, onset of reactions, treatment, and inpatient stay. To evaluate the incidence of this severe complication, a survey of all listed burn care units in Germany, Austria, and Switzerland as well as the legal advisory boards of the medical associations of the federal states of Germany was conducted. The conditions leading to photochemotherapy were three cases of psoriasis vulgaris and one case of severe chronic graft vs host disease. All patients received oral psoralen. Incorrect handling of the radiation system was the reason for all burns. The mean affected TBSA was 73±18%. All patients were treated conservatively and healed without surgical intervention. Burn injury is a serious and preventable complication of PUVA photochemotherapy. Patients should be advised regarding the potential risk of major burns. Care should be given to not exceed the safe dose of psoralen. Burn care specialists must restrain surgical intervention as even deep partial thickness PUVA burns have the potential to heal spontaneously.


Assuntos
Queimaduras/etiologia , Terapia PUVA/efeitos adversos , Adulto , Unidades de Queimados , Feminino , Alemanha , Doença Enxerto-Hospedeiro/tratamento farmacológico , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Psoríase/tratamento farmacológico , Estudos Retrospectivos , Inquéritos e Questionários
13.
Dent Traumatol ; 29(2): 84-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22520279

RESUMO

BACKGROUND: Regenerative endodontics is an innovative treatment concept aiming to regenerate pulp, dentin and root structures. In the diseased or necrotic tooth, the limitation in vascular supply renders successful tissue regeneration/generation in a whole tooth challenging. The aim of this study is to evaluate the ability of vascularized tissue to develop within a pulpless tooth using tissue engineering techniques. MATERIALS AND METHODS: A pulpless tooth chamber, filled with collagen I gel containing isolated rat dental pulp cells (DPC) and angiogenic growth factors, was placed into a hole created in the femoral cortex or into its own tooth socket, respectively. The gross, histological and biochemical characteristics of the de novo tissue were evaluated at 4 and 8 weeks post-transplantation. RESULTS: Tooth revascularization and tissue generation was observed only in the femur group, confirming the important role of vascular supply in tissue regeneration. The addition of cells and growth factors significantly promoted connective tissue production in the tooth chamber. CONCLUSION: Successful revascularization and tissue regeneration in this model demonstrate the importance of a direct vascular supply and the advantages of a stem cell approach.


Assuntos
Cavidade Pulpar/metabolismo , Polpa Dentária/irrigação sanguínea , Regeneração/fisiologia , Células-Tronco/metabolismo , Engenharia Tecidual/métodos , Animais , Colágeno/metabolismo , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Técnicas Histológicas , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia , Alicerces Teciduais , Dente não Vital
14.
In Vivo ; 26(4): 559-63, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22773568

RESUMO

BACKGROUND: Undifferentiated pleomorphic sarcoma not otherwise specified (NOS) is a malignant neoplasm of uncertain origin arising both in the soft tissue and the bone. The WHO classified this tumour in 2002 but controversy has plagued this entity due to limited availability of tissue for study. The aim of this study was to establish a reproducible xenograft model of primary human undifferentiated pleomorphic sarcoma NOS. MATERIALS AND METHODS: Primary human sarcoma samples were divided into tumour fragments and transplanted subcutaneously in mice. Sarcoma xenografts were analysed histolomorphologically (light/electron-microscopy; immunohistochemistry). RESULTS: All tumours resulted in viable sarcoma NOS xenografts demonstrating similar histological patterns. In both the original tumours and the xenografts, tumour necrosis was found ranging from 15% to 25%. The background stroma of the xenografts was hyalinised like the primary sarcoma. Electron microscopical analyses showed good maintenance of ultrastructure. CONCLUSION: Implantation of intact tumor fragments yielded in a complete tumor take rate. The development of new cancer therapeutics requires animal models that closely resemble the human patient. This study provides ideal animal models for the research of pathogenesis and pathobiology of primary human undifferentiated pleomorphic sarcoma NOS.


Assuntos
Diferenciação Celular , Modelos Animais de Doenças , Sarcoma Experimental/patologia , Animais , Masculino , Camundongos , Camundongos Nus
15.
Anticancer Res ; 32(4): 1167-73, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22493346

RESUMO

BACKGROUND: Sarcomas consist of both tumor and stromal cells, and the interaction between these compartments is critical for tumor progression and metastasis. Tumor-derived factors may alter the differentiation capacity of the adjacent stromal cells. The aim of this study was to elucidate the paracrine impact of liposarcoma cells on pre-adipocytes, their adipogenic differentiation process and miRNA expression profile. MATERIALS AND METHODS: 3T3-L1 pre-adipocytes were exposed to sarcoma pre-conditioned media. Following induction of adipogenic differentiation morphometrical changes were assessed. Differences in miRNA expression of conditioned and non-conditioned 3T3-L1 cells were analyzed. RESULTS: Exposure to sarcoma pre-conditioned media substantially altered the differentiation capability of 3T3-L1 pre-adipocytes. Significant changes in the miRNA expression profile between conditioned and non-conditioned pre-adipocytes were observed. CONCLUSION: Sarcoma cells directly modulate pre-adipocyte differentiation. This study demonstrates that sarcoma cells influence differentiation of pre-adipocytes via paracrine factors and alter their miRNA expression.


Assuntos
Adipócitos/citologia , Diferenciação Celular , Sarcoma/patologia , Células 3T3-L1 , Animais , Humanos , Camundongos , MicroRNAs/metabolismo
16.
Biomaterials ; 33(15): 3868-79, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22369961

RESUMO

The effects of in vitro preconditioning protocols on the ultimate survival of myoblasts implanted in an in vivo tissue engineering chamber were examined. In vitro testing: L6 myoblasts were preconditioned by heat (42 °C; 1.5 h); hypoxia (<8% O(2); 1.5 h); or nitric oxide donors: S-nitroso-N-acetylpenicillamine (SNAP, 200 µM, 1.5 h) or 1-[N-(2-aminoethyl)-N-(2-aminoethyl)amino]-diazen-1-ium-1,2-diolate (DETA-NONOate, 500 µM, 7 h). Following a rest phase preconditioned cells were exposed to 24 h hypoxia, and demonstrated minimal overall cell loss, whilst controls (not preconditioned, but exposed to 24 h hypoxia) demonstrated a 44% cell loss. Phosphoimmunoblot analysis of pro-survival signaling pathways revealed significant activation of serine threonine kinase Akt with DETA-NONOate (p < 0.01) and heat preconditioning (p < 0.05). DETA-NONOate also activated ERK 1/2 signaling (p < 0.05). In vivo implantation: 100,000 preconditioned (heat, hypoxia, or DETA-NONOate) myoblasts were implanted in SCID mouse tissue engineering chambers. 100,000 (not preconditioned) myoblasts were implanted in control chambers. At 3 weeks, morphometric assessment of surviving myoblasts indicated myoblast percent volume (p = 0.012) and myoblasts/mm(2) (p = 0.0005) overall significantly increased in preconditioned myoblast chambers compared to control, with DETA-NONOate-preconditioned myoblasts demonstrating the greatest increase in survival (p = 0.007 and p = 0.001 respectively). DETA-NONOate therefore has potential therapeutic benefits to significantly improve survival of transplanted cells.


Assuntos
Modelos Biológicos , Mioblastos/citologia , Engenharia Tecidual/métodos , Animais , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/crescimento & desenvolvimento , Contagem de Células , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desmina/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos SCID , Mioblastos/efeitos dos fármacos , Mioblastos/enzimologia , Compostos Nitrosos/farmacologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Implantação de Prótese , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Alicerces Teciduais
17.
J Orthop Res ; 29(8): 1237-44, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21381095

RESUMO

Sufficient induction of blood vessel ingrowth decisively influence transplant functionality. In this study, microvascular response to transplants of surface modified bone substitutes were assessed in vivo. The surface modification of allogenic bone substitutes (dehydrated human femoral head) was achieved in a double-conductive low-pressure gasplasma reactor (Ar(2) /O(2) , 13.65 MHz, 1,000 W, 5 Pa). The modified bone substitutes (n = 10) as well as untreated bone substitutes serving as controls (n = 10) were placed into the dorsal skinfold chamber of female balb/c mice (n = 10). Dynamic assessment of microcirculatory parameters was performed using intravital fluorescence microscopy during an implantation period of 10 days. The angiogenic response was found markedly accelerated in gasplasma-treated bone. Compared to untreated implants, the gasplasma-activated bone substitutes showed significantly higher microvascular density on days 5 and 10. The quantification of the microvascular diameters, red blood cell velocity, and microvascular permeability displayed stable perfusion and vascular integrity of the newly developed blood vessels throughout the 10-day observation period. The surface activation via cold low-pressure glow discharge gasplasma supports the vascular integration of allogenic bone by earlier induction of the angiogenesis.


Assuntos
Substitutos Ósseos , Transplante Ósseo , Neovascularização Fisiológica/efeitos dos fármacos , Gases em Plasma/farmacologia , Animais , Feminino , Cabeça do Fêmur , Reação a Corpo Estranho , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microcirculação , Espectroscopia Fotoeletrônica
18.
Spine (Phila Pa 1976) ; 36(18): E1225-9, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21325991

RESUMO

STUDY DESIGN: Retrospective chart review. OBJECTIVE: The aim of this study was to analyze the correlation between necrotizing fasciitis (NF) and pressure ulcers, as well as the mortality, and complication rate, in patients with spinal cord injury (SCI). SUMMARY OF BACKGROUND DATA: Pressure ulcers represent a challenging problem, especially in immobilized patients. Necrotizing soft tissue infections arising from decubitus ulcers in patients with SCIs have been reported. METHODS: Twenty-five SCI patients with NF treated between April 2000 and December 2009 were included in the study. All patients were analyzed in regard to the number of surgical debridements, length of hospital stay, and laboratory, microbiological, and histological assessments. Information about age, sex, preexisting conditions, anatomical localization, and etiology of the NF were acquired from the patients' medical records. RESULTS: There were 19 paraplegic and 6 tetraplegic patients with a median age of 47 years. In 18 cases, NF developed in the setting of pressure sores. Grade 4 pressure sores were identified in 15 cases and grade 3 pressure sores in 3 cases. The incidence of developing NF is significantly higher in patients with fourth-grade pressure sores than in those with a lower-grade lesion (odds ratio = 2.91; 95% confidence interval, 1.29-6.56). The mean laboratory risk indicator for NF score was 6.6 upon admission. The most common bacteria were streptococci. During the hospital stay, six patients developed sepsis and two died because of septic multiorgan failure. CONCLUSION: Patients with grade 3 and 4 pressure sores had a significantly increased risk of developing NF. The current investigators recommend that close clinical and laboratory monitoring of all patients with grade 3 or 4 pressure sores is appropriate so that any early clinical signs of NF can be recognized and evaluated for early and aggressive treatment.


Assuntos
Fasciite Necrosante/complicações , Úlcera por Pressão/complicações , Traumatismos da Medula Espinal/complicações , Adulto , Idoso , Antibacterianos/uso terapêutico , Infecções Bacterianas/complicações , Desbridamento/métodos , Fasciite Necrosante/microbiologia , Fasciite Necrosante/terapia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Paraplegia/complicações , Quadriplegia/complicações , Estudos Retrospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Sepse/complicações
19.
World J Surg Oncol ; 8: 103, 2010 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-21092216

RESUMO

BACKGROUND: Leiomysarcoma of intravascular origin is an exceedingly rare entity of malignant soft tissue tumors. They are most frequently encountered in the retroperitoneum arising from the inferior vena cava and are scarcely found to arise from vessels of the extremities. These tumors were analysed with particular reference to treatment outcome and prognosis. The aim of this article is to broaden the knowledge of the clinical course of this rare malignancy. METHOD: During 2000 and 2009 twelve patients were identified with an intravascular origin of a leiomyosarcoma. Details regarding the clinical course, follow-up and outcome were assessed with focus on patient survival, tumor relapse and metastases and treatment outcome. 3 year survival probability was calculated using Kaplan-Meier method. RESULTS: Vascular leiomyosarcomas accounted for 0.7% of all malignant soft tissue tumors treated at our soft tissue sarcoma reference center. The mean follow up period was 38 months. Tumor relapse was encountered in six patients. 6 patients developed metastatic disease. The three year survival was 57%. CONCLUSION: Vascular leiomysarcoma is a rare but aggressive tumor entity with a high rate of local recurrence and metastasis.


Assuntos
Leiomiossarcoma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Vasculares/patologia , Veia Cava Inferior/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Diagnóstico Diferencial , Feminino , Humanos , Leiomiossarcoma/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia , Estudos Prospectivos , Dosagem Radioterapêutica , Taxa de Sobrevida , Resultado do Tratamento , Neoplasias Vasculares/terapia
20.
Cells Tissues Organs ; 192(3): 141-57, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20357428

RESUMO

Recreating an environment that supports and promotes fundamental homeostatic mechanisms is a significant challenge in tissue engineering. Optimizing cell survival, proliferation, differentiation, apoptosis and angiogenesis, and providing suitable stromal support and signalling cues are keys to successfully generating clinically useful tissues. Interestingly, those components are often subverted in the cancer setting, where aberrant angiogenesis, cellular proliferation, cell signalling and resistance to apoptosis drive malignant growth. In contrast to tissue engineering, identifying and inhibiting those pathways is a major challenge in cancer research. The recent discovery of adult tissue-specific stem cells has had a major impact on both tissue engineering and cancer research. The unique properties of these cells and their role in tissue and organ repair and regeneration hold great potential for engineering tissue-specific constructs. The emerging body of evidence implicating stem cells and progenitor cells as the source of oncogenic transformation prompts caution when using these cells for tissue-engineering purposes. While tissue engineering and cancer research may be considered as opposed fields of research with regard to their proclaimed goals, the compelling overlap in fundamental pathways underlying these processes suggests that cross-disciplinary research will benefit both fields. In this review article, tissue engineering and cancer research are brought together and explored with regard to discoveries that may be of mutual benefit.


Assuntos
Neoplasias/etiologia , Neoplasias/patologia , Engenharia Tecidual/tendências , Animais , Pesquisa Biomédica , Humanos , Neoplasias/metabolismo , Regeneração/fisiologia , Células-Tronco/citologia , Células-Tronco/patologia , Células-Tronco/fisiologia , Engenharia Tecidual/efeitos adversos
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