Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nano Lett ; 23(20): 9353-9359, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37819646

RESUMO

Phenalenyl is a radical nanographene with a triangular shape hosting an unpaired electron with spin S = 1/2. The open-shell nature of the phenalenyl is expected to be retained in covalently bonded networks. As a first step, we report synthesis of the phenalenyl dimer by combining in-solution synthesis and on-surface activation and its characterization on Au(111) and on a NaCl decoupling layer by means of inelastic electron tunneling spectroscopy (IETS). IETS shows inelastic steps that are identified as singlet-triplet excitation arising from interphenalenyl exchange. Spin excitation energies with and without the NaCl decoupling layer are 48 and 41 meV, respectively, indicating significant renormalization due to exchange with Au(111) electrons. Furthermore, third-neighbor hopping-induced interphenalenyl hybridization is fundamental to explaining the position-dependent bias asymmetry of the inelastic steps and activation of kinetic interphenalenyl exchange. Our results pave the way for bottom-up synthesis of S = 1/2 spin-lattices with large exchange interactions.

2.
J Autoimmun ; 133: 102953, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36410262

RESUMO

Antineutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV) comprises a group of multisystem disorders involving severe, systemic, small-vessel vasculitis with short- and long term serious and life-threating complications. Despite the simplification of treatment, fundamental aspects concerning assessment of its efficacy and its adaptation to encountered complications or to the relapsing/remitting/subclinical disease course remain still unknown. The pathogenesis of AAV is complex and unique, and despite the progress achieved in the last years, much has not to be learnt. Foremost, there is still no accurate marker enabling us to monitoring disease and guide therapy. Therefore, the disease management relays often on clinical judgment and follows a" trial and error approach". In the recent years, an increasing number of new molecules s have been explored and used for this purpose including genomics, B- and T-cell subpopulations, complement system factors, cytokines, metabolomics, biospectroscopy and components of our microbiome. The aim of this review is to discuss both the role of known historical and clinically established biomarkers of AAV, as well as to highlight potential new ones, which could be used for timely diagnosis and monitoring of this devastating disease, with the goal to improve the effectiveness and ameliorate the complications of its demanding therapy.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Metabolômica , Humanos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Genômica
3.
Thorac Cardiovasc Surg ; 67(3): 170-175, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29804285

RESUMO

BACKGROUND: Minimally invasive left ventricular assist device (LVAD) implantation may reduce peri-/postoperative complications and risks associated with resternotomies. In this study, we describe our first results using a minimally invasive LVAD implantation technique (lateral thoracotomy [LT] group). These results were compared with LVAD implantations done via full median sternotomy (STX group). METHODS: HVAD (HeartWare, Framingham, Massachusetts, United States) implantations in 70 patients (LT group n = 22, 52 ± 15 years old; STX group n = 48, 59 ± 11 years old) were retrospectively analyzed. Minimally invasive access via left thoracotomy was feasible in 22 patients. Peri- and postoperative analyses of survival and adverse events were performed. RESULTS: No survival differences were observed between the LT and STX group (p = 0.43). LT patients without temporary right ventricular assist device (tRVAD) showed a significantly better survival rate compared to LT patients with concomitant tRVAD implantation (p = 0.02), which could not be demonstrated in the STX group (p = 0.11). Two LT and four STX patients were successfully bridged to heart transplantation and three STX patients were successfully weaned with subsequent LVAD explantations. LVAD-related infections (n = 4 LT group vs n = 20 STX group, p = 0.04) were less likely in the LT group. No wound dehiscence occurred in the LT group, whereas five were observed in the STX group (p = 0.17). The amount of perioperative blood transfusions (within the first 7 postoperative days) did not differ in both study groups (p = 0.48). CONCLUSION: The minimally invasive approach is a viable alternative with the possibility to reduce complications and should be particularly considered for bridge-to-transplant patients.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Implantação de Prótese/instrumentação , Implantação de Prótese/métodos , Esternotomia , Toracotomia/métodos , Função Ventricular Esquerda , Adulto , Idoso , Feminino , Alemanha , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Implantação de Prótese/mortalidade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Esternotomia/efeitos adversos , Esternotomia/mortalidade , Toracotomia/efeitos adversos , Toracotomia/mortalidade , Fatores de Tempo , Resultado do Tratamento
4.
Eur Cell Mater ; 33: 28-42, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28098926

RESUMO

Cell-based in vitro resorption assays are an important tool to simulate the in vivo biodegradation of resorbable bone graft materials and to predict their clinical performance. The present study analyses the activity of osteoclast-specific enzymes as potential surrogate measures for classical pit assay, which is not applicable on irregular structured materials. Osteoclasts derived from human peripheral blood mononuclear cells were cultivated on different surfaces: calcium phosphate bone cements (CPC), dentin discs, osteoblast-derived extracellular matrix (ECM) and tissue culture polystyrene as control. Pit formation on the resorbable materials was investigated and correlated with the activity of tartrate resistant acid phosphatase (TRAP), carbonic anhydrase II (CAII) and cathepsin K (CTSK). Furthermore, the relation between intra- and extracellular enzyme activities was examined for TRAP and CTSK during resorption of the different materials. Resorbed area of CPC correlated with intracellular TRAP activity and intracellular CAII activity. Highest resorption was detected at around pH 7.2. Resorbed area on dentin correlated with the extracellular CTSK activity and extracellular TRAP activity and was maximal at around pH 6.8. Osteoclasts cultivated on cell-derived mineralised ECM showed a good correlation between both extracellular TRAP and CTSK activity and the release of calcium ions. Based on these data a different regulation of TRAP and CTSK secretion is hypothesised for the resorption of inorganic calcium phosphate compared to the resorption of collagenous mineralised matrix.


Assuntos
Bioensaio/métodos , Reabsorção Óssea/enzimologia , Osteoclastos/enzimologia , Cimentos Ósseos/farmacologia , Matriz Óssea/efeitos dos fármacos , Matriz Óssea/metabolismo , Reabsorção Óssea/patologia , Fosfatos de Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Dentina/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Humanos , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Osteoblastos/patologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Osteoclastos/ultraestrutura , Poliestirenos/farmacologia , Coloração e Rotulagem , Fosfatase Ácida Resistente a Tartarato/metabolismo
5.
Hautarzt ; 65(6): 542-7, 2014 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-24706078

RESUMO

BACKGROUND: Skin lesions due to Fusarium spp. occur either secondarily following hematological spread in systemic infection or represent primary cutaneous infections following traumatic inoculation. CASE REPORT: A 34-year-old woman with insulin-dependent diabetes mellitus presented with a most likely posttraumatic leg ulcer present for 4 weeks. The ulcer showed superficial necrosis with cellular debris, neutrophils, and leukocytoclasia. Septate hyphae were detected both in the necrotic area and between the collagen fibers on initial H & E stained sections. Using PAS and Grocott-Gomori silver staining, the dichotomous branching hyphae were clearly visible. Unfortunately, cultural detection of the fungi was impossible. After extraction and purification of the fungal DNA from formalin-fixed and paraffin embedded (FFPE) tissue sections, the amplification of the ITS region of rDNA was done. Using sequencing and comparison with reference sequences of a gene bank, Fusarium oxysporum was identified. THERAPY: Therapy was performed by surgical excision of the entire ulcer followed by topical antiseptic treatment and wound conditioning. No systemic antifungal treatment was given. The lesion healed without any problems. DISCUSSION: Cutaneous fusarium infections are rare but emerging opportunistic infections. Histological examination represents the quickest diagnostic method for detection of the fungal infection. An alternative approach represents the species identification based on molecular techniques.


Assuntos
Dermatomicoses/diagnóstico , Dermatomicoses/microbiologia , Fusariose/diagnóstico , Fusariose/microbiologia , Fusarium/genética , Úlcera da Perna/diagnóstico , Úlcera da Perna/microbiologia , Adulto , DNA Ribossômico/genética , Dermatomicoses/cirurgia , Feminino , Formaldeído , Fusariose/cirurgia , Fusarium/classificação , Fusarium/isolamento & purificação , Marcadores Genéticos/genética , Humanos , Úlcera da Perna/cirurgia , Técnicas de Diagnóstico Molecular , Inclusão em Parafina , Análise de Sequência de DNA/métodos , Fixação de Tecidos , Resultado do Tratamento
6.
Eur J Cardiothorac Surg ; 66(4)2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39259187

RESUMO

OBJECTIVES: Bridging from a temporary microaxial left ventricular assist device (tLVAD) to a durable left ventricular assist device (dLVAD) is playing an increasing role in the treatment of terminally ill patients with heart failure. Scant data exist about the best implant strategy. The goal of this study was to analyse differences in the dLVAD implant technique and effects on patient outcomes. METHODS: Data from 341 patients (19 European centres) who underwent a bridge-to-bridge implant from tLVAD to dLVAD between January 2017 and October 2022 were retrospectively analysed. The outcomes of the different implant techniques with the patient on cardiopulmonary bypass, extracorporeal life support or tLVAD were compared. RESULTS: A durable LVAD implant was performed employing cardiopulmonary bypass in 70% of cases (n = 238, group 1), extracorporeal life support in 11% (n = 38, group 2) and tLVAD in 19% (n = 65, group 3). Baseline characteristics showed no significant differences in age (P = 0.140), body mass index (P = 0.388), creatinine level (P = 0.659), the Model for End-Stage Liver Disease (MELD) score (P = 0.190) and rate of dialysis (P = 0.110). Group 3 had significantly fewer patients with preoperatively invasive ventilation and cardiopulmonary resuscitation before the tLVAD was implanted (P = 0.009 and P < 0.001 respectively). Concomitant procedures were performed more often in groups 1 and 2 compared to group 3 (24%, 37% and 5%, respectively, P < 0.001). The 30-day mortality data showed significantly better survival after an inverse probability of treatment weighting in group 3, but the 1-year mortality showed no significant differences among the groups (P = 0.012 and 0.581, respectively). Postoperative complications like the rate of right ventricular assist device (RVAD) implants or re-thoracotomy due to bleeding, postoperative respiratory failure and renal replacement therapy showed no significant differences among the groups. Freedom from the first adverse event like stroke, driveline infection or pump thrombosis during follow-up was not significantly different among the groups. Postoperative blood transfusions within 24 h were significantly higher in groups 1 and 2 compared to surgery on tLVAD support (P < 0.001 and P = 0.003, respectively). CONCLUSIONS: In our analysis, the transition from tLVAD to dLVAD without further circulatory support did not show a difference in postoperative long-term survival, but a better 30-day survival was reported. The implant using only tLVAD showed a reduction in postoperative transfusion rates, without increasing the risk of postoperative stroke or pump thrombosis. In this small cohort study, our data support the hypothesis that a dLVAD implant on a tLVAD is a safe and feasible technique in selected patients.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Insuficiência Cardíaca/cirurgia , Insuficiência Cardíaca/terapia , Idoso , Resultado do Tratamento , Adulto
7.
J Mater Sci Mater Med ; 24(7): 1755-66, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23625348

RESUMO

Conventionally sintered hydroxyapatite-based materials for bone repair show poor resorbability due to the loss of nanocrystallinity. The present study describes a method to establish nanocrystalline hydroxyapatite granules. The material was prepared by ionotropic gelation of an alginate sol containing hydroxyapatite (HA) powder. Subsequent thermal elimination of alginate at 650 °C yielded non-sintered, but unexpectedly stable hydroxyapatite granules. By adding stearic acid as an organic filler to the alginate/HA suspension, the granules exhibited macropores after thermal treatment. A third type of material was achieved by additional coating of the granules with silica particles. Microstructure and specific surface area of the different materials were characterized in comparison to the already established granular calcium phosphate material Cerasorb M(®). Cytocompatibility and potential for bone regeneration of the materials was evaluated by in vitro examinations with osteosarcoma cells and osteoclasts. Osteoblast-like SaOS-2 cells proliferated on all examined materials and showed the typical increase of alkaline phosphatase (ALP) activity during cultivation. Expression of bone-related genes coding for ALP, osteonectin, osteopontin, osteocalcin and bone sialoprotein II on the materials was proven by RT-PCR. Human monocytes were seeded onto the different granules and osteoclastogenesis was examined by activity measurement of tartrate-specific acid phosphatase (TRAP). Gene expression analysis after 23 days of cultivation revealed an increased expression of osteoclast-related genes TRAP, vitronectin receptor and cathepsin K, which was on the same level for all examined materials. These results indicate, that the nanocrystalline granular materials are of clinical interest, especially for bone regeneration.


Assuntos
Regeneração Óssea , Durapatita/química , Durapatita/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Adulto , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/genética , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Substitutos Ósseos/uso terapêutico , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Durapatita/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Regeneração Tecidual Guiada/instrumentação , Regeneração Tecidual Guiada/métodos , Humanos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoblastos/fisiologia , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteoclastos/fisiologia , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteogênese/fisiologia , Tamanho da Partícula , Pós/química , Pós/farmacologia , Pós/uso terapêutico , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
8.
Pathologe ; 34(6): 540-7, 2013 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-24043212

RESUMO

BACKGROUND: Due to the lack of histopathological differentiation the unequivocal identification of fungal pathogens is rarely possible. In order to understand the pathogen spectrum causing cephalic mycosis the use of alternative methods is essential. MATERIAL AND METHODS: In a retrospective study 24 formalin-fixed, paraffin-embedded (FFPE) samples from patients with histologically confirmed cerebral or cephalic mycosis were analyzed with molecular biological methods. RESULTS: In two samples obtained during the patients' lifetime human as well as fungal DNA was detected, making an unambiguous diagnosis possible. For tissue that had been fixed over a longer period, detection of human and fungal DNA was possible merely in 60% and 47 % of the samples, respectively. Most frequently diagnosed were aspergillosis (n = 9), followed by mucormycosis (n = 2) and imported blastomycosis (n = 1). CONCLUSIONS: Using biopsy material a DNA analysis seems promising although only with limited success using brain samples taken at autopsy which have been fixed over a longer period. For unambiguous retrospective diagnostics of pathogens when cephalic mycosis is suspected, the sample extraction for postmortem diagnostics should be performed prior to a long period of formalin fixation.


Assuntos
Encefalopatias/microbiologia , Encefalopatias/patologia , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Infecções Fúngicas do Sistema Nervoso Central/patologia , Doenças dos Seios Paranasais/patologia , Adulto , Idoso , Encéfalo/microbiologia , Encéfalo/patologia , DNA Fúngico/análise , DNA Fúngico/genética , Feminino , Fixadores , Formaldeído , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Tipagem Micológica , Infecções Oportunistas/microbiologia , Infecções Oportunistas/patologia , Inclusão em Parafina , Doenças dos Seios Paranasais/microbiologia
9.
Clin Genet ; 82(3): 240-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21883168

RESUMO

Marfan syndrome is considered a clinical diagnosis. Three diagnostic classifications comprising first, Marfan genotype with a causative FBN1 gene mutation; second, Marfan phenotype with clinical criteria of the original Ghent nosology (Ghent-1); and third, phenotype with clinical criteria of its current revision (Ghent-2) in 300 consecutive persons referred for confirmation or exclusion of Marfan syndrome (150 men, 150 women aged 35 ± 13 years) were used. Sequencing of TGBR1/2 genes was performed in 128 persons without FBN1 mutation. Marfan genotype was present in 140, Ghent-1 phenotype in 139, and Ghent-2 phenotype in 124 of 300 study patients. Marfan syndrome was confirmed in 94 and excluded in 129 persons consistently by all classifications, but classifications were discordant in 77 persons. With combined genotype and phenotype information confirmation of Marfan syndrome was finally achieved in 126 persons by Ghent-1 and in 125 persons by Ghent-2 among 140 persons with Marfan genotype, and exclusion was accomplished in 139 persons by Ghent-1 and in 141 persons by Ghent-2 among 160 persons without Marfan genotype. In total, genotype information changed final diagnoses in 22 persons with Ghent-1, and in 32 persons with Ghent-2. It is concluded that genotype information is essential for diagnosis or exclusion of Marfan syndrome.


Assuntos
Genótipo , Síndrome de Marfan/diagnóstico , Síndrome de Marfan/genética , Fenótipo , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Clin Genet ; 79(6): 568-74, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20662850

RESUMO

Mutations in the genes FBN1, TGFBR1, and TGFBR2 can result in heritable connective tissue disorders comprising the Marfan syndrome and the Loeys-Dietz syndrome. Dural ectasia is a characteristic manifestation of both syndromes. However, dural ectasia has not yet been investigated in connective tissue disorders that are unrelated to mutations in the FBN1, TGFBR1 or TGFBR2 genes. Here, we assessed dural ectasia in 33 individuals both with typical manifestations of heritable connective tissue disease and in whom mutations in all three genes had been excluded. We identified 19 individuals with dural ectasia (58%), who exhibited major skeletal manifestations of the Marfan syndrome more frequently than the remaining 14 persons without dural ectasia (p = 0.06). Moreover, only persons with dural ectasia fulfilled clinical criteria of the Marfan syndrome (p = 0.01). Conversely, aortic aneurysm (12 patients; p = 0.8), aortic dissection (five patients; p = 0.1), spontaneous dissection of the carotid arteries (five patients; p = 1), and mitral valve prolapse (13 patients; p = 0.4) were similarly frequent irrespective of dural ectasia. We conclude that dural ectasia is a marker for connective tissue disease which coincides with skeletal rather than with cardiovascular manifestations, and which may involve currently uncharacterized pathogenetic mechanisms and syndromes.


Assuntos
Dura-Máter/anormalidades , Síndrome de Marfan/diagnóstico , Proteínas dos Microfilamentos/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Seio Aórtico/anormalidades , Adolescente , Adulto , Criança , Análise Mutacional de DNA , Diagnóstico Diferencial , Dilatação Patológica/diagnóstico , Dilatação Patológica/genética , Feminino , Fibrilina-1 , Fibrilinas , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Adulto Jovem
11.
Ann Oncol ; 21(11): 2267-2271, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20439346

RESUMO

BACKGROUND: Patients not fulfilling minimal criteria for myelodysplastic syndromes (MDS) but presenting with persisting cytopenia(s) not attributable to a haematological or non-haematological disease are defined as 'idiopathic cytopenia of undetermined significance' (ICUS). DESIGN AND METHODS: We retrospectively analysed 67 of 3504 patients from our MDS Registry fulfilling the criteria for ICUS. Furthermore, we used the human androgen receptor gene-based assay (HUMARA) to look for clonality. RESULTS: Of all 67 patients, 66% had unilineage, 18% bilineage and 12% trilineage cytopenias. The majority of patients (67%) presented with anaemia. Median overall survival was 44 months (range: 1-199 months). In the entire group, eight patients (12%) developed acute myeloid leukaemia (AML). Of the 23 patients eligible for HUMARA, 17 had non-clonal X-chromosome inactivation patterns, while 6 patients showed clonal patterns. Two of these six patients developed AML indicating that a clonal stem cell disorder was the reason for the anteceding cytopenia, while there was no AML observed among the 17 patients with non-clonal patterns (P = 0.013). CONCLUSIONS: Since some of the ICUS patients had a clonal bone marrow disease when presenting with cytopenia(s) and 8 of 67 patients with ICUS later developed AML, we recommend to follow these patients thoroughly. As demonstrated here, HUMARA can facilitate the discrimination between ICUS and a 'manifest' MDS.


Assuntos
Doenças da Medula Óssea/diagnóstico , Síndromes Mielodisplásicas/diagnóstico , Receptores Androgênicos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças da Medula Óssea/genética , Células Clonais , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/genética , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
12.
Eur Cell Mater ; 19: 96-106, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20186669

RESUMO

Textile chitosan fibre scaffolds were evaluated in terms of interaction with osteoclast-like cells, derived from human primary monocytes. Part of the scaffolds was further modified by coating with fibrillar collagen type I in order to make the surface biocompatible. Monocytes were cultured directly on the scaffolds in the presence of macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor kappaB ligand (RANKL) for up to 18 days. Confocal laser scanning microscopy (CLSM) as well as scanning electron microscopy (SEM) revealed the formation of multinuclear osteoclast-like cells on both the raw chitosan fibres and the collagen-coated scaffolds. The modified surface supported the osteoclastogenesis. Differentiation towards the osteoclastic lineage was confirmed by the microscopic detection of cathepsin K, tartrate resistant acid phosphatase (TRAP), acidic compartments using 3-(2,4-dinitroanillino)-3'-amino-N-methyldipropylamine (DAMP), immunological detection of TRAP isoform 5b, and analysis of gene expression of the osteoclastic markers TRAP, cathepsin K, vitronectin receptor, and calcitonin receptor using reverse transcription-polymerase chain reaction (RT-PCR). The feature of the collagen-coated but also of the raw chitosan fibre scaffolds to support attachment and differentiation of human monocytes facilitates cell-induced material resorption--one main requirement for successful bone tissue engineering.


Assuntos
Substitutos Ósseos/farmacologia , Quitosana/farmacologia , Monócitos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Engenharia Tecidual/métodos , Alicerces Teciduais/tendências , Fosfatase Ácida/análise , Fosfatase Ácida/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Substitutos Ósseos/química , Substitutos Ósseos/uso terapêutico , Catepsina K/análise , Catepsina K/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Linhagem da Célula/efeitos dos fármacos , Linhagem da Célula/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quitosana/química , Quitosana/uso terapêutico , Colágeno/química , Colágeno/farmacologia , Colágeno/uso terapêutico , Humanos , Integrina alfaVbeta3/genética , Isoenzimas/análise , Isoenzimas/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Microscopia Confocal , Microscopia Eletrônica de Varredura , Monócitos/fisiologia , Monócitos/ultraestrutura , Osteoclastos/fisiologia , Osteoclastos/ultraestrutura , Ligante RANK/farmacologia , Receptores da Calcitonina/genética , Fosfatase Ácida Resistente a Tartarato
13.
Vasa ; 39(1): 3-16, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20186672

RESUMO

Despite advanced techniques for surgical or percutaneous therapy coarctation of the aorta continues to carry a high risk of aneurysmal formation. Mortality of these aneurysms ranges between <1 and >90%, reflecting remarkable differences in surgical strategies and the follow-up management of coarctation. We review the frequency, anatomical types, risk factors and mechanisms of aortic aneurysm forming late after surgical or percutaneous therapy of aortic coarctation. We emphasize that aneurysms do not form exclusively at the site of previous intervention, but also at remote locations such as the ascending aorta. Moreover, aneurysm formation may only in part be attributed to a specific technique of coarctation therapy, and we emphasize the role of a bicuspid aortic valve and inherent weakness of the aortic wall as significant risk factors for aneurysm after aortic coarctation. We report the presenting symptoms, follow-up protocols, and imaging criteria for local and proximal aneurysms. Finally, we discuss criteria for prophylactic intervention at the site of such aneurysms, and present therapeutic options for different types of aneurysms. With this systematic review, we wish to provide data for establishing more uniform strategies for preventing, diagnosing and treating aneurysms associated with aortic coarctation.


Assuntos
Aneurisma Aórtico/epidemiologia , Coartação Aórtica/complicações , Coartação Aórtica/cirurgia , Aorta Torácica/anormalidades , Aorta Torácica/anatomia & histologia , Aorta Torácica/patologia , Aorta Torácica/cirurgia , Aneurisma Aórtico/etiologia , Aneurisma Aórtico/mortalidade , Aneurisma Aórtico/terapia , Estenose da Valva Aórtica/cirurgia , Velocidade do Fluxo Sanguíneo , Implante de Prótese Vascular/métodos , Humanos , Cuidados Pós-Operatórios
14.
Vasa ; 39(1): 17-32, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20186673

RESUMO

Marfan syndrome (MFS) is a disorder of the connective tissue that is inherited in an autosomal dominant fashion and that is classically caused by mutations in the gene coding for fibrillin-1, FBN1. The high mortality of untreated MFS results almost exclusively from aortic complications such as aortic dissection and rupture. However, more than half of patients with Marfan-like features do not have MFS, but have other diseases including inherited aortic aneurysms and dissections (TAAD). We elucidate the increasing spectrum of syndromes associated with Marfan-like features and discuss the clinical implications of these diseases. We performed a systematic review to tabulate all known inherited diseases and syndromes carrying a risk for thoracic aortic disease. We discuss evidence that different syndromes with different causative genes and mutations have different prognoses and profiles of cardiovascular manifestations. We conclude that future decisions for optimized management of patients with inherited TAAD require a comprehensive clinical and genetic work-up.


Assuntos
Aorta Torácica/patologia , Doenças da Aorta/complicações , Doenças da Aorta/genética , Síndrome de Marfan/complicações , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/cirurgia , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/epidemiologia , Dissecção Aórtica/genética , Dissecção Aórtica/cirurgia , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/cirurgia , Doenças da Aorta/diagnóstico , Doenças da Aorta/cirurgia , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/genética , Genes Dominantes , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/genética , Humanos , Síndrome de Marfan/genética , Fatores de Risco , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/genética
16.
Anaesthesist ; 57(6): 578-81, 2008 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-18463835

RESUMO

This report describes a case where a continuous lumbar epidural anesthesia was inserted for an operation in a patient with classical hemophilia which was unknown at the time of catheter insertion. In addition to an exact description of the intervention, the anamnesis and laboratory contraindications for epidural anesthesia are discussed. Furthermore, the necessity of preoperative investigations and their value when an epidural anesthesia is planned are also discussed.


Assuntos
Anestesia Epidural , Hemofilia A/complicações , Idoso de 80 Anos ou mais , Anestesia Epidural/efeitos adversos , Cateterismo , Contraindicações , Herniorrafia , Humanos , Masculino , Monitorização Intraoperatória , Medicação Pré-Anestésica , Risco
17.
J Biomed Mater Res A ; 81(2): 474-83, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17133509

RESUMO

Calcium phosphate bone cements are of great interest for bone replacement since the nanocrystalline structure allows their remodelling into native bone tissue. A strategy to accelerate vascularization of the implant region is the functionalization with vascular endothelial growth factor (VEGF), which is known to mediate angiogenesis in vivo. In this study, the release of recombinant human VEGF (rhVEGF(165)) following physical adsorption to Biocement D (BioD) and several modifications were investigated. Our data demonstrate a high VEGF binding capacity of BioD and a sustained release with a moderate initial burst. A proliferation assay using endothelial cells revealed maintenance of biological activity of VEGF after release from BioD. Release behavior of BioD was not improved by modification with mineralized collagen type I, as well as with a combination of mineralized collagen with O-phospho-L-serine and sodium citrate, respectively. In contrast, a positive impact of these modifications on the activity of released VEGF was observed; in case of the phosphoserine- and sodium citrate-modified cements, the biological efficacy of released VEGF was even higher than that of nonreleased control VEGF. We conclude that the bone implant material BioD and, especially, the phosphoserine modification may support activation of angiogenesis by delivery of VEGF in a local and sustained manner.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/química , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/farmacocinética , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Sistemas de Liberação de Medicamentos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Humanos , Técnicas In Vitro , Teste de Materiais , Neovascularização Fisiológica/efeitos dos fármacos , Compostos Orgânicos/química , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacologia , Propriedades de Superfície , Fator A de Crescimento do Endotélio Vascular/farmacologia
18.
J Tissue Eng Regen Med ; 11(6): 1710-1722, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-26178016

RESUMO

Studies on tissue-engineering approaches for the regeneration of traumatized cartilage focus increasingly on multipotent human mesenchymal stem cells (hMSCs) as an alternative to autologous chondrocytes. The present study applied porous scaffolds made of collagen from the jellyfish Rhopilema esculentum for the in vitro chondrogenic differentiation of hMSCs. Culture conditions in those scaffolds differ from conditions in high-density pellet cultures, making a re-examination of these data necessary. We systematically investigated the influence of seeding density, basic culture media [Dulbecco's modified Eagle's medium (DMEM), α-minimum essential medium (α-MEM)] with varying glucose content and supplementation with fetal calf serum (FCS) or bovine serum albumin (BSA) on the chondrogenic differentiation of hMSCs. Gene expression analyses of selected markers for chondrogenic differentiation and hypertrophic development were conducted. Furthermore, the production of cartilage extracellular matrix (ECM) was analysed by quantification of sulphated glycosaminoglycan and collagen type II contents. The strongest upregulation of chondrogenic markers, along with the highest ECM deposition was observed in scaffolds seeded with 2.4 × 106 cells/cm3 after cultivation in high-glucose DMEM and 0.125% BSA. Lower seeding densities compared to high-density pellet cultures were sufficient to induce in vitro chondrogenic differentiation of hMSCs in collagen scaffolds, which reduces the amount of cells required for the seeding of scaffolds and thus the monolayer expansion period. Furthermore, examination of the impact of FCS and α-MEM on chondrogenic MSC differentiation is an important prerequisite for the development of an osteochondral medium for simultaneous osteogenic and chondrogenic differentiation in biphasic scaffolds for osteochondral tissue regeneration. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Cartilagem , Condrogênese , Colágeno/química , Células-Tronco Mesenquimais/metabolismo , Cifozoários/química , Alicerces Teciduais/química , Animais , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Humanos , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos
19.
Gefasschirurgie ; 22(Suppl 1): 8-16, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28715514

RESUMO

BACKGROUND: Guidelines summarize medical evidence, they identify the most efficient therapy under study conditions and recommend this therapy for use. The physician now has the challenge to translate a therapy that is efficient under laboratory conditions to a patient who is an individual person. To accomplish this task the physician has to make sure that (I) the ideal typical therapy is applicable and effective in this individual patient taking the special features into consideration, that (II) therapy is compliant with the norm including guidelines, laws and ethical requirements (conformity) and that (III) the therapy meets the patient's needs. OBJECTIVE: How can physicians together with the patients translate the medical evidence into an individually optimized therapy? MATERIAL AND METHODS: At the German Aortic Center in Hamburg we use I­SWOT as an instrument to identify such individually optimized therapy. With I­SWOT, we present an instrument with which we have developed an (I) efficient, (II) conform and (III) needs-oriented therapeutic strategy for individual patients. RESULTS: I-SWOT cross-tabulates strengths (S) and weaknesses (W) related to therapy with opportunities (O) and threats (T) related to individual patients. This I­SWOT matrix identifies four fundamental types of strategy, which comprise "SO" maximizing strengths and opportunities, "WT" minimizing weaknesses and threats, "WO" minimizing weaknesses and maximizing opportunities and "ST" maximizing strengths and minimizing threats. We discuss the case of a patient with asymptomatic thoracoabdominal aneurysm to show how I­SWOT is used to identify an individually optimized therapy strategy.

20.
Mater Sci Eng C Mater Biol Appl ; 64: 190-198, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27127044

RESUMO

Marine, hybrid constructs of porous scaffolds from fibrillized jellyfish collagen and alginate hydrogel are mimicking both of the main tissue components of cartilage, thus being a promising approach for chondrogenic differentiation of human mesenchymal stem cells (hMSC). Investigating their potential for articular cartilage repair, the present study examined scaffolds being either infiltrated with an alginate-cell-suspension (ACS) or seeded with hMSC and embedded in alginate after cell adhesion (EAS). Hybrid constructs with 2×10(5) and 4.5×10(5)hMSC/scaffold were compared to hMSC encapsulated in pure alginate discs, both chondrogenically stimulated for 21days. Typical round, chondrocyte-like morphology was observed in pure alginate gels and ACS scaffolds, while cells in EAS were elongated and tightly attached to the collagen pores. Col 2 gene expression was comparable in all scaffold types examined. However, the Col 2/Col 1 ratio was higher for pure alginate discs and ACS scaffolds compared to EAS. In contrast, cells in EAS scaffolds displayed higher gene expression of Sox 9, Col 11 and ACAN compared to ACS and pure alginate. Secretion of sulfated glycosaminoglycans (sGAG) was comparable for ACS and EAS scaffolds. In conclusion hybrid constructs of jellyfish collagen and alginate support hMSC chondrogenic differentiation and provide more stable and constructs compared to pure hydrogels.


Assuntos
Alginatos/química , Diferenciação Celular , Condrogênese , Colágeno/química , Células-Tronco Mesenquimais/metabolismo , Cifozoários/química , Animais , Células Cultivadas , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Células-Tronco Mesenquimais/citologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA