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The aim of the present study was to develop a collagen/heparin-based multilayer coating on titanium surfaces for retarded release of recombinant human bone morphogenic protein 2 (rhBMP2) to enhance the osteogenic activity of implant surfaces. Polyelectrolyte multilayer (PEM) coatings were constructed on sandblasted/acid-etched surfaces of titanium discs using heparin and collagen. PEM films of ten double layers were produced and overlayed with 200 µL of a rhBMP2 solution containing 15 µg rhBMP2. Subsequently, cross-linking of heparin molecules was performed using EDC/NHS chemistry to immobilize the incorporated rhBMP2. Release characteristics for 3 weeks, induction of Alkaline Phosphatase (ALP) in C2C12 cells and proliferation of human mesenchymal stem cells (hMSCs) were evaluated to analyze the osteogenic capacity of the surface. The coating incorporated 10.5 µg rhBMP2 on average per disc and did not change the surface morphology. The release profile showed a delivery of 14.5% of the incorporated growth factor during the first 24 h with a decline towards the end of the observation period with a total release of 31.3%. Cross-linking reduced the release with an almost complete suppression at 100% cross-linking. Alkaline Phosphatase was significantly increased on day 1 and day 21, indicating that the growth factor bound in the coating remains active and available after 3 weeks. Proliferation of hMSCs was significantly enhanced by the non-cross-linked PEM coating. Nanocoating using collagen/heparin-based PEMs can incorporate clinically relevant amounts of rhBMP2 on titanium surfaces with a retarded release and a sustained enhancement of osteogenic activity without changing the surface morphology.
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Fosfatase Alcalina , Titânio , Fosfatase Alcalina/metabolismo , Diferenciação Celular , Proliferação de Células , Colágeno/química , Heparina , Humanos , Osteogênese , Propriedades de Superfície , Titânio/químicaRESUMO
Hemodynamic conditions with reduced systemic vascular resistance commonly are observed in patients undergoing cardiac surgery and may range from moderate reductions in vascular tone, as a side effect of general anesthetics, to a profound vasodilatory syndrome, often referred to as vasoplegic shock. Therapy with vasopressors is an important pillar in the treatment of these conditions. There is limited guidance on the appropriate choice of vasopressors to restore and optimize systemic vascular tone in patients undergoing cardiac surgery. A panel of experts in the field convened to develop statements and evidence-based recommendations on clinically relevant questions on the use of vasopressors in cardiac surgical patients, using a critical appraisal of the literature following the GRADE system and a modified Delphi process. The authors unanimously and strongly recommend the use of norepinephrine and/or vasopressin for restoration and maintenance of systemic perfusion pressure in cardiac surgical patients; despite that, the authors cannot recommend either of these drugs with respect to the risk of ischemic complications. The authors unanimously and strongly recommend against using dopamine for treating post-cardiac surgery vasoplegic shock and against using methylene blue for purposes other than a rescue therapy. The authors unanimously and weakly recommend that clinicians consider early addition of a second vasopressor (norepinephrine or vasopressin) if adequate vascular tone cannot be restored by a monotherapy with either norepinephrine or vasopressin and to consider using vasopressin as a first-line vasopressor or to add vasopressin to norepinephrine in cardiac surgical patients with pulmonary hypertension or right-sided heart dysfunction.
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Procedimentos Cirúrgicos Cardíacos , Choque , Consenso , Humanos , Norepinefrina , Vasoconstritores/uso terapêutico , VasopressinasRESUMO
Genome-wide enrichment of methylated DNA followed by sequencing (MeDIP-seq) offers a reasonable compromise between experimental costs and genomic coverage. However, the computational analysis of these experiments is complex, and quantification of the enrichment signals in terms of absolute levels of methylation requires specific transformation. In this work, we present QSEA, Quantitative Sequence Enrichment Analysis, a comprehensive workflow for the modelling and subsequent quantification of MeDIP-seq data. As the central part of the workflow we have developed a Bayesian statistical model that transforms the enrichment read counts to absolute levels of methylation and, thus, enhances interpretability and facilitates comparison with other methylation assays. We suggest several calibration strategies for the critical parameters of the model, either using additional data or fairly general assumptions. By comparing the results with bisulfite sequencing (BS) validation data, we show the improvement of QSEA over existing methods. Additionally, we generated a clinically relevant benchmark data set consisting of methylation enrichment experiments (MeDIP-seq), BS-based validation experiments (Methyl-seq) as well as gene expression experiments (RNA-seq) derived from non-small cell lung cancer patients, and show that the workflow retrieves well-known lung tumour methylation markers that are causative for gene expression changes, demonstrating the applicability of QSEA for clinical studies. QSEA is implemented in R and available from the Bioconductor repository 3.4 (www.bioconductor.org/packages/qsea).
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Metilação de DNA , Genômica/métodos , Análise de Sequência de DNA/métodos , Animais , Teorema de Bayes , Regulação da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Camundongos , Regiões Promotoras Genéticas , Sulfitos , Fluxo de TrabalhoRESUMO
Following publication of the original article [1], we have been alerted to errors in Figs. 2 and 8. In Fig. 2B, the GAPDH loading control for Hec1A cells is shown twice in error (in Fig. 2B and Fig. 2C). In Fig. 8, in testis case 1 (first column) the MAGE-A4 staining panel was repeated and also appears as the NY-ESO-1 staining panel in error. The corrected versions of Fig. 2 and Fig. 8 are shown below. We apologize for this inconvenience.
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Background Sparse data are available on the prevalence of right ventricular dysfunction and/or pulmonary arterial hypertension in patients scheduled for cardiac surgery in Germany as well as on the intensity and modalities used for diagnosis, perioperative monitoring, and treatment of these comorbidities. Methods A postal survey including questions on the prevalence of preoperative right ventricular dysfunction and/or pulmonary arterial hypertension in patients undergoing cardiac surgery in 2009 was sent to 81 German heart centers. Total 47 of 81 (58%) heart centers returned the questionnaires. The centers reported data on 51,095 patients, and 49.8% of the procedures were isolated coronary artery bypass grafting. Results Data on the prevalence of preoperative pulmonary hypertension and/or right ventricular dysfunction were not available in 54% and 64.6% of centers. In the remaining hospitals, 19.5% of patients presented right heart dysfunction and 10% pulmonary arterial hypertension. Preoperative echocardiography was performed in only 45.3% of the coronary artery bypass grafting cases. Preoperative pharmacologic treatment of pulmonary hypertension or right ventricular dysfunction with oral sildenafil, inhaled prostanoids, or nitric oxide was initiated in 71% and 95.7% of the centers, respectively. Intra- and postoperative treatment was most frequently accomplished with phosphodiesterase-III inhibitors. Conclusion The prevalence of preoperative right heart dysfunction and pulmonary arterial hypertension in cardiac surgical patients in Germany seems to be substantial. However, in more than 50% of the patients, no preoperative data on right ventricular function and pulmonary arterial pressure are available. This may lead to underestimation of perioperative risk and inappropriate management of this high-risk population.
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Procedimentos Cirúrgicos Cardíacos , Hipertensão Pulmonar/epidemiologia , Disfunção Ventricular Direita/epidemiologia , Anti-Hipertensivos/uso terapêutico , Pressão Arterial , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ecocardiografia , Alemanha/epidemiologia , Inquéritos Epidemiológicos , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/fisiopatologia , Prevalência , Artéria Pulmonar/fisiopatologia , Medição de Risco , Fatores de Risco , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/tratamento farmacológico , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular DireitaRESUMO
BACKGROUND: Anesthesia for pediatric cardiac surgery requires a high level of expert knowledge. There are currently no recommendations and standards for anesthetic management for congenital cardiac surgery in Germany. AIM: The aim of the present study was to assess the current status of structural and personnel anesthetic standards at pediatric cardiac surgery centers in Germany. METHODS: All cardiac surgical centers in Germany were reviewed for an active program for congenital heart surgery. Centers with an active program were invited to respond to an online survey. The questionnaire containing 55 items in 16 categories assessed current practice in pediatric cardiac anesthesia. RESULTS: An active program for pediatric cardiac surgery was identified at 27 centers. The response rate to the survey was 96.3%. A specialized group of anesthesiologists for pediatric cardiac anesthesia was reported from 26 centers (92.3%). The mean size of this group was 4.8 anesthesiologists per center. However, the annual case load of centers and relative annual case load per specialized anesthesiologist varied considerably between 12.5 and 250. Nonanesthesiologists performed sedation and general anesthesia for diagnostic and therapeutic interventions outside the operating theater in children with congenital heart diseases in 24 centers (77%). Although special equipment, for example, pediatric TEE, near-infrared spectroscopy, and devices for mechanical auto transfusion were available in most centers, their routine use was not always part of standard operating procedures. The proposal for mean adequate training in pediatric cardiac anesthesia as estimated by the participating centers was 10.8 months. CONCLUSION: The present study represents the current structural situation for anesthesia at German pediatric cardiac surgery centers.
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Anestesia/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Cirurgia Torácica/estatística & dados numéricos , Anestesiologistas , Anestesiologia/educação , Criança , Sedação Consciente , Alemanha , Pesquisas sobre Atenção à Saúde , Cardiopatias Congênitas/cirurgia , Humanos , Equipe de Assistência ao Paciente , Pediatria/educação , Indicadores de Qualidade em Assistência à Saúde , Inquéritos e Questionários , Cirurgia Torácica/educação , Recursos HumanosRESUMO
INTRODUCTION: Central venous saturation (ScvO2) monitoring has been suggested to address the issue of adequate cardiocirculatory function in the context of cardiac surgery. The aim of this study was to determine the impact of low (L) (<60%), normal (N) (60%-80%), and high (H) (>80%) ScvO2 measured on intensive care unit (ICU) admission after cardiac surgery. METHODS: We conducted a retrospective, cross-sectional, observational study at three ICUs of a university hospital department for anaesthesiology and intensive care. Electronic patient records of all adults who underwent cardiac surgery between 2006 and 2013 and available admission measurements of ScvO2 were examined. Patients were allocated to one of three groups according to first ScvO2 measurement after ICU admission: group L (<60%), group N (60%-80%), and group H (>80%). Primary end-points were in-hospital and 3-year follow-up survival. RESULTS: Data from 4,447 patients were included in analysis. Low and high initial measurements of ScvO2 were associated with increased in-hospital mortality (L: 5.6%; N: 3.3%; H: 6.8%), 3-year follow-up mortality (L: 21.6%; N: 19.3%; H: 25.8%), incidence of post-operative haemodialysis (L: 11.5%; N: 7.8%; H: 15.3%), and prolonged hospital length of stay (L: 13 days, 9-22; N: 12 days, 9-19; H: 14 days, 9-21). After adjustment for possible confounding variables, an initial ScvO2 above 80% was associated with adjusted hazard ratios of 2.79 (95% confidence interval (CI) 1.565-4.964, P <0.001) for in-hospital survival and 1.31 (95% CI 1.033-1.672, P = 0.026) for 3-year follow-up survival. CONCLUSIONS: Patients with high ScvO2 were particularly affected by unfavourable outcomes. Advanced haemodynamic monitoring may help to identify patients with high ScvO2 who developed extraction dysfunction and to establish treatment algorithms to improve patient outcome in these patients.
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Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cateteres Venosos Centrais , Cuidados Críticos/normas , Mortalidade Hospitalar , Oxigênio/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Estudos Transversais , Humanos , Oxigênio/metabolismo , Estudos Prospectivos , Estudos RetrospectivosRESUMO
BACKGROUND: Breast cancer is a heterogeneous disease displaying distinct molecular features and clinical outcome. The molecular profile of triple-negative breast cancers (TNBCs) overlaps with that of basal-like breast cancers that in turn show similarities with high-grade serous ovarian and endometrial carcinoma. L1CAM is an established biomarker for the latter cancers and we showed before that approximately 18% of primary breast cancers are positive for L1CAM and have a bad prognosis. Here we analysed the expression of L1CAM breast cancer subtypes. METHODS: We analyzed mRNA and protein expression data from different breast cancer cohorts for L1CAM, estrogen receptor, progesterone receptor, Her-2 and Androgen receptor (AR) and correlated the data. We performed Western blot analysis on tumor cell lysates and carried out chromatin-immuno-precipitation (CHIP) after AR overexpression. RESULTS: We find that L1CAM is expressed preferentially though not exclusively in TNBCs. Using the human cancer genome atlas database and two independent breast cancer cohorts we find that L1CAM is inversely correlated with androgen receptor (AR) expression. We found that L1CAM(high)AR(low) primary breast tumors have the worst clinical outcome. Overexpression of AR in MDA-MB436 breast cancer cells decreased L1CAM expression at the protein and mRNA level and CHIP-analysis revealed binding of AR to the L1CAM promoter region. CONCLUSIONS: These results suggest that L1CAM in breast cancer is under AR control. The data also strongly advocate the use of L1CAM assessment in breast cancer diagnosis. We suggest that L1CAM expression could be causally related to the bad prognosis of TNBCs.
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Regulação Neoplásica da Expressão Gênica , Molécula L1 de Adesão de Célula Nervosa/genética , Receptores Androgênicos/genética , Neoplasias de Mama Triplo Negativas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sítios de Ligação , Biomarcadores Tumorais , Linhagem Celular Tumoral , Bases de Dados Genéticas , Feminino , Humanos , Pessoa de Meia-Idade , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Prognóstico , Regiões Promotoras Genéticas , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Androgênicos/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidadeRESUMO
The more we come to understand the pathophysiology of heparin-induced thrombocytopenia (HIT) syndrome, the more we realize that HIT is a rather unusual immune response. One peculiar feature of HIT is the transient character of the antibodies. After cessation of exposure to heparins, the antibodies tend to disappear after 40-100 days. If re-immunization occurs, it generally takes at least 4 days to redevelop antibodies (if they are formed at all). We report about a patient who most likely developed platelet-activating IgG-specific platelet factor 4 (PF4)/heparin antibodies after knee surgery, experienced a transient ischemic attack years later [when HIT was diagnosed by using PF4/heparin ELISA] and presented a high number of these antibodies even 4 years after this first diagnosis of HIT without further re-exposure to heparin.
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Anticorpos/imunologia , Heparina/efeitos adversos , Ativação Plaquetária/efeitos dos fármacos , Fator Plaquetário 4/imunologia , Trombocitopenia/induzido quimicamente , Idoso , Humanos , MasculinoRESUMO
Localized jawbone invasion is a milestone in the progression of oral squamous cell carcinoma (OSCC). The factors that promote this process are not well understood. Sclerostin is known to be involved in bone metabolism and there are preliminary reports of its involvement in bone tumors and bone metastasis. To identify a possible involvement of sclerostin in the bone invasion process of OSCC, sclerostin expression was analyzed in vitro in two different human OSCC tumor cell lines by quantitative real-time polymerase chain reaction (qRT-PCR), and the effect of recombinant human (rh)-sclerostin treatment on tumor cell capabilities was evaluated using proliferation, migration, and invasion assays. Undifferentiated human mesenchymal stem cells (hMSCs) were osteogenically differentiated and co-cultured with OSCC tumor cells to demonstrate potential interactions and migration characteristics. Sclerostin expression was evaluated in clinical cases by immunohistochemistry at the OSCC-jawbone interface in a cohort of 15 patients. Sclerostin expression was detected in both OSCC tumor cell lines in vitro and was also detected at the OSCC-jawbone interface in clinical cases. Tumor cell proliferation rate, migration and invasion ability were increased by rh-sclerostin treatment. The migration rate of tumor cells co-cultured with osteogenically differentiated hMSCs was increased. The results presented are the first data suggesting a possible involvement of sclerostin in the bone invasion process of OSCC, which deserves further investigation and may be a potential approach for drug-based tumor therapy.
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Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Bioensaio , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismoRESUMO
BACKGROUND: L1CAM was originally identified as an adhesion molecule involved in neural development. In many human carcinomas L1CAM is over-expressed and is associated with a bad prognosis. We previously reported that L1CAM was absent in the vast majority of endometrioid endometrial carcinomas (ECs) (type 1) but was strongly expressed in the more aggressive serous and clear-cell ECs (termed type 2). The differential regulation of L1CAM in ECs is not well understood. Recent evidence suggests that it can be regulated by epigenetic mechanisms. Here we investigated the role of DNA-methylation of the L1CAM promoter for expression. We also studied the relationship to cancer testis (CT-X) antigens that co-localize with L1CAM on chromosome Xq28, a region that is often activated in human tumors. METHODS: We used EC cell lines and primary tumor tissues for our analysis. For expression analysis we employed RT-PCR and Western blotting. DNA-Methylation of the L1CAM promoter was determined after bisulfite conversation and DNA sequencing. Tumor tissues were examined by immunohistochemical (IHC) staining. RESULTS: We demonstrate that the treatment of L1CAM low/negative expressing EC cell lines with 5'-Azacytidine (5-AzaC) or knock-down of DNMT1 (DNA methyltransferase 1) as well as the HDAC (histone deacetylase) inhibitor Trichostatin A (TSA) up-regulated L1CAM at the mRNA and protein level. The L1CAM gene has two promoter regions with two distinct CpG islands. We observed that the expression of L1CAM correlated with hypermethylation in promoter 1 and 5-AzaC treatment affected the DNA-methylation pattern in this region. The CT-X antigens NY-ESO-1, MAGE-A3 and MAGE-A4 were also strongly up-regulated by 5-AzaC or knock-down of DNMT1 but did not respond to treatment with TSA. Primary EC tumor tissues showed a variable methylation pattern of the L1CAM promoter. No striking differences in promoter methylation were observed between tumor areas with L1CAM expression and those without expression. CONCLUSIONS: L1CAM expression correlated with methylation of the L1CAM promoter in EC cell lines. In negative cell lines L1CAM expression is up-regulated by epigenetic mechanism. Although genes localized on Xq28 are often re-expressed by human tumors, L1CAM and CT-X antigens show distinct regulation in response to HADC inhibitors and 5-AzaC.
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Neoplasias do Endométrio/genética , Epigênese Genética , Molécula L1 de Adesão de Célula Nervosa/genética , Adulto , Idoso , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Neoplasias do Endométrio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas , Testículo/metabolismo , Adulto JovemRESUMO
Expression of L1 cell adhesion molecule (L1CAM) is associated with poor prognosis in a variety of human carcinomas including breast, ovarian and pancreatic ductal adenocarcinoma (PDAC). Recently we reported that L1CAM induces sustained nuclear factor kappa B (NF-κB) activation by augmenting the autocrine production of interleukin 1 beta (IL-1ß), a process dependent on interaction of L1CAM with integrins. In the present study, we demonstrate that transforming growth factor ß1 (TGF-ß1) treatment of breast carcinoma (MDA-MB231) and PDAC (BxPc3) cell lines induces an EMT (epithelial to mesenchymal transition)-like phenotype and leads to the expression of L1CAM. In MDA-MB231 cells, up-regulation of L1CAM augmented expression of IL-1ß and NF-κB activation, which was reversed by depletion of L1CAM, L1CAM-binding membrane cytoskeleton linker protein ezrin, ß1-integrin or focal adhesion kinase (FAK). Over-expression of L1CAM not only induced NF-κB activation but also mediated the phosphorylation of FAK and Src. Phosphorylation was not induced in cells expressing a mutant form of L1CAM (L1-RGE) devoid of the integrin-binding site. FAK- and Src-phosphorylation were inhibited by knock-down of various components of the integrin signalling pathway such as ß1- and α5-integrins, integrin-linked kinase (ILK), FAK and the phosphoinositide 3-kinase (PI3K) subunit p110ß. In summary, these results reveal that during EMT, L1CAM promotes IL-1ß expression through a process dependent on integrin signalling and supports a motile and invasive tumour cell phenotype. We also identify important novel downstream effector molecules of the L1CAM-integrin signalling crosstalk that help to understand the molecular mechanisms underlying L1CAM-promoted tumour progression.
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Neoplasias da Mama/metabolismo , Transição Epitelial-Mesenquimal , Interleucina-1beta/biossíntese , NF-kappa B/biossíntese , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Neoplasias Pancreáticas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proteínas do Citoesqueleto/metabolismo , Ativação Enzimática , Feminino , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Integrina beta1/metabolismo , Neoplasias Pancreáticas/patologia , Fosforilação , Transdução de Sinais , Regulação para CimaRESUMO
Polyelectrolyte multilayers (PEM) are versatile tools used to investigate fundamental interactions between material-related parameters and the resulting performance in stem cell differentiation, respectively, in bone tissue engineering. In the present study, we investigate the suitability of PEMs with a varying collagen content for use as drug carriers for the human bone morphogenetic protein 2 (rhBMP-2). We use three different PEM systems consisting either of the positively charged poly-L-lysine or the glycoprotein collagen type I and the negatively charged glycosaminoglycan heparin. For a specific modification of the loading capacity and the release kinetics, the PEMs were stepwise cross-linked before loading with cytokine. We demonstrate the possibility of immobilizing significant amounts of rhBMP-2 in all multilayer systems and to specifically tune its release via cross-linking. Furthermore, we prove that the drug release of rhBMP-2 plays only a minor role in the differentiation of osteoprogenitor cells. We find a significantly higher influence of the immobilized rhBMP-2 within the collagen-rich coatings that obviously represent an excellent mimicry of the native extracellular matrix. The cytokine immobilized in its bioactive form was able to achieve an increase in orders of magnitude both in the early stages of differentiation and in late calcification compared to the unloaded layers.
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The aim of the present study was to establish a modular platform of poly-L-lysine-heparin (PLL-Hep) polyelectrolyte multilayer (PEM) coatings on titanium surfaces for dual growth factor delivery of recombinant human bone morphogenic protein 2 (rhBMP2) and recombinant human vascular endothelial growth factor 165 (rhVEGF165) in clinically relevant quantities. Release characteristics for both growth factors differed significantly depending on film architecture. rhBMP2 induced activation of alkaline phosphatase in C2C12 cells and proliferation of human mesenchymal stem cells (hMSCs). rhVEGF mediated induction of von Willebrand factor (vWF) in hMSCs and proliferation of human umbilical vein endothelial cells. Osteogenic and angiogenic effects were modified by variation in cross-linking and architecture of the PEMs. By creating multilayer films with distinct zones, release characteristics and proportion of both growth factor delivery could be tuned and surface-activity modified to enhance angiogenic or osteogenic function in various ways. In summary, the system provides a modular platform for growth factor delivery that allows for individual composition and accentuation of angiogenic and osteogenic surface properties.
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Heparina , Titânio , Proliferação de Células , Heparina/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Propriedades de Superfície , Titânio/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologiaRESUMO
The layer-by-layer (LbL) self-assembly technique is an effective method to immobilize components of the extracellular matrix (ECM) such as collagen and heparin onto, e.g., implant surfaces/medical devices with the aim of forming polyelectrolyte multilayers (PEMs). Increasing evidence even suggests that cross-linking influences the physicochemical character of PEM films since mechanical cues inherent to the substrate may be as important as its chemical nature to influence the cellular behavior. In this study, for the first-time different collagen/heparin films have been prepared and cross-linked with EDC/NHS chemistry. Quartz crystal microbalance, zeta potential analyzer, diffuse reflectance Fourier transform infrared spectroscopy, atomic force microscopy and ellipsometry were used to characterize film growth, stiffness, and topography of different film systems. The analysis of all data proves a nearly linear film growth for all PEM systems, the efficacy of cross-linking and the corresponding changes in the film rigidity after cross-linking and an appropriate surface topography. Furthermore, preliminary cell culture experiments illustrated those cellular processes correlate roughly with the quantity of newly created covalent amide bonds. This allows a precise adjustment of the physicochemical properties of the selected film architecture regarding the desired application and target cells. It could be shown that collagen improves the biocompatibility of heparin containing PEMs and due to their ECM-analogue nature both molecules are ideal candidates intended to be used for any biomedical application with a certain preference to improve the performance of bone implants or bone augmentation strategies.
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Heparin-induced thrombocytopenia (HIT) is caused by newly formed platelet-activating antibodies against complexes formed between platelet factor 4 (PF4) and heparin (H). HIT can result in life-threatening complications; thus, early detection of HIT antibodies is crucial for the treatment of the disease. The enzyme-linked immune absorbance assay (ELISA) for the identification of HIT antibodies is widely used in many laboratories, but in general, this test provides only â¼50% accuracy while other methods show multiple limitations. Here, we developed a new cell-based ELISA to improve the detection of HIT antibodies. Instead of immobilizing PF4 or PF4/H complexes directly onto a plate as in the standard ELISA, we added the complexes on breast cancer cells, i.e., cell line MDA-MB-231, and applied the same protocol for antibody detection. Using confocal laser scanning microscopy and flow cytometry for the characterization of bound complexes, we identified two types of HIT-mimicked antibodies (KKO and 1E12), which were able to differentiate from the non-HIT antibody (RTO). PF4-treated MDA-MB-231 cells allowed binding of HIT-mimicked antibodies better than PF4/H complexes. With human sera, the cell-based ELISA allowed better differentiation of clinically relevant from non-clinically relevant HIT antibodies as compared with the standard ELISA. Our findings provide a potential approach that contributes to the development of better assays for the detection of HIT antibodies.
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Neoplasias da Mama , Trombocitopenia , Anticorpos , Neoplasias da Mama/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Feminino , Heparina/efeitos adversos , Humanos , Fator Plaquetário 4/efeitos adversos , Fator Plaquetário 4/metabolismo , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnósticoRESUMO
BACKGROUND: The L1 cell adhesion molecule (L1CAM) is potentially involved in epithelial-mesenchymal transition (EMT). EMT marker expression is of prognostic significance in non-small cell lung cancer (NSCLC). The relevance of L1CAM for NSCLC is unclear. We investigated the protein expression of L1CAM in a cohort of NSCLC patients. L1CAM protein expression was correlated with clinico-pathological parameters including survival and markers of epithelial-mesenchymal transition. RESULTS: L1CAM protein expression was found in 25% of squamous cell carcinomas and 24% of adenocarcinomas and correlated with blood vessel invasion and metastasis (p < 0.05). L1CAM was an independent predictor of survival in a multivariate analysis including pT, pN, and pM category, and tumor differentiation grade. L1CAM expression positively correlated with vimentin, beta-catenin, and slug, but inversely with E-cadherin (all p-values < 0.05). E-cadherin expression was higher in the tumor center than in the tumor periphery, whereas L1CAM and vimentin were expressed at the tumor-stroma interface. In L1CAM-negative A549 cells the L1CAM expression was upregulated and matrigel invasion was increased after stimulation with TGF-beta1. In L1CAM-positive SK-LU-1 and SK-LC-LL cells matrigel invasion was decreased after L1CAM siRNA knockdown. CONCLUSIONS: A subset of NSCLCs with vessel tropism and increased metastasis aberrantly expresses L1CAM. L1CAM is a novel prognostic marker for NSCLCs that is upregulated by EMT induction and appears to be instrumental for enhanced cell invasion.
Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Pulmonares/metabolismo , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Molécula L1 de Adesão de Célula Nervosa/genética , Prognóstico , Interferência de RNARESUMO
Endometrial carcinomas (ECs) are classified into type 1 (less aggressive) and type 2 (aggressive) tumours that differ in genetic alterations. So far, reliable immunohistochemical markers that can identify patients with high risk for recurrence are rare. We have defined the expression of L1 cell adhesion molecule (L1CAM), a biomarker previously identified for EC, and compared its expression to oestrogen receptor (ER)/progesterone receptor (PR) and E-cadherin. We found that L1CAM was absent in normal endometrium and the vast majority of endometrioid ECs (type 1) but was strongly expressed in serous and clear-cell ECs, considered as type 2. 78/272 cases were identified as L1CAM-positive endometrioid ECs that were correlated with a poor prognosis. Strikingly, we observed an inverse relationship between L1CAM and ER/PR/E-cadherin expression in all ECs. In mixed ECs, composed of endometrioid (L1CAM(-) ER/PR(+) E-cadherin(+)) and clear-cell/serous (L1CAM(+) ER/PR(-) E-cadherin(-)), both phenotypes were co-expressed. In some of these cases L1CAM was up-regulated at the leading edge of the tumour, where ER/PR and E-cadherin expression were selectively lost. In EC cell lines treated with the epithelial-mesenchymal transition (EMT) inducer TGFbeta1, L1CAM and vimentin were strongly up-regulated, while E-cadherin expression was reduced. The treatment also resulted in an increased expression of the EMT transcription factor Slug and an enhanced cell invasion. Depletion of Slug by siRNA knockdown prevented both L1CAM up-regulation and enhanced cell invasion. According to our analysis, we suggest that L1CAM is a novel marker for EMT in ECs and that L1CAM-typing could identify endometrioid ECs that have type 2-like features and are at high risk for recurrence.
Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias do Endométrio/metabolismo , Proteínas de Neoplasias/metabolismo , Molécula L1 de Adesão de Célula Nervosa/biossíntese , Regulação para Cima , Biomarcadores Tumorais/genética , Caderinas/metabolismo , Neoplasias do Endométrio/patologia , Endométrio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas Imunoenzimáticas , Invasividade Neoplásica/fisiopatologia , Molécula L1 de Adesão de Célula Nervosa/genética , Prognóstico , RNA Neoplásico/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacosRESUMO
PURPOSE OF REVIEW: Hemorrhage, transfusions and the need for re-exploration can have a detrimental effect on patient outcome in cardiac surgery. With the suspension of aprotinin from the market, only the antifibrinolytics tranexamic acid and epsilon-aminocaproic acid (EACA) are left as pharmacological options to reduce hemostatic activation and associated bleeding complications. In light of the aprotinin story, the need for large independent safety studies has become evident. The current review will focus on the question of how far the quality of available data allows for judging these agents with regard to safety and efficacy, as well as whether or not new trails are warranted. RECENT FINDINGS: Both, tranexamic acid and EACA are effective in reducing blood loss and transfusion requirements in cardiac surgery. Analysis of data is complicated as the dosing scheme, especially for tranexamic acid, varies extremely and the agents are highly overdosed in most relevant trials. Newer data indicates that in a dose-dependent fashion, tranexamic acid is associated with an increase of adverse events, particularly the observation of seizures. In these studies, however, tranexamic acid has also been highly overdosed. SUMMARY: The lysine analogs are unspecific enzyme inhibitors. Therefore, it is conceivable that an overdosing might reveal severe clinical side-effects beyond the inhibition of plasmin. Further studies re-evaluating the drug safety of tranexamic acid and EACA using the recommended and approved doses are necessary.