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1.
Eur J Cancer ; 185: 28-39, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36947929

RESUMO

BACKGROUND: Local treatment improves the outcomes for oligometastatic disease (OMD, i.e. an intermediate state between locoregional and widespread disseminated disease). However, consensus about the definition, diagnosis and treatment of oligometastatic oesophagogastric cancer is lacking. The aim of this study was to develop a multidisciplinary European consensus statement on the definition, diagnosis and treatment of oligometastatic oesophagogastric cancer. METHODS: In total, 65 specialists in the multidisciplinary treatment for oesophagogastric cancer from 49 expert centres across 16 European countries were requested to participate in this Delphi study. The consensus finding process consisted of a starting meeting, 2 online Delphi questionnaire rounds and an online consensus meeting. Input for Delphi questionnaires consisted of (1) a systematic review on definitions of oligometastatic oesophagogastric cancer and (2) a discussion of real-life clinical cases by multidisciplinary teams. Experts were asked to score each statement on a 5-point Likert scale. The agreement was scored to be either absent/poor (<50%), fair (50%-75%) or consensus (≥75%). RESULTS: A total of 48 experts participated in the starting meeting, both Delphi rounds, and the consensus meeting (overall response rate: 71%). OMD was considered in patients with metastatic oesophagogastric cancer limited to 1 organ with ≤3 metastases or 1 extra-regional lymph node station (consensus). In addition, OMD was considered in patients without progression at restaging after systemic therapy (consensus). For patients with synchronous or metachronous OMD with a disease-free interval ≤2 years, systemic therapy followed by restaging to consider local treatment was considered as treatment (consensus). For metachronous OMD with a disease-free interval >2 years, either upfront local treatment or systemic treatment followed by restaging was considered as treatment (fair agreement). CONCLUSION: The OMEC project has resulted in a multidisciplinary European consensus statement for the definition, diagnosis and treatment of oligometastatic oesophagogastric adenocarcinoma and squamous cell cancer. This can be used to standardise inclusion criteria for future clinical trials.


Assuntos
Neoplasias , Humanos , Técnica Delphi , Europa (Continente)
2.
Ann Surg ; 275(6): e759-e765, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32740246

RESUMO

OBJECTIVE: Neoadjuvant chemoradiotherapy followed by surgery establishes a considerable pathologic complete response (pCR) in EC. The aim was to determine site of residual tumor and its prognostic impact. SUMMARY BACKGROUND DATA: High rates of residual tumor in the adventitial region even inside the radiation fields will influence current decision-making. METHODS: We evaluated resection specimens with marked target fields from 151 consecutive EC patients treated with carboplatin/paclitaxel and 41.4Gy between 2009 and 2018. RESULTS: In radically resected (R0) specimens 19.8% (27/136) had a pCR (ypT0N0) and 14% nearly no response (tumor regression grade: tumor regression grade 4-5). Residual tumor commonly extended in or restricted to the adventitia (43.1%; 47/109), whereas 7.3% was in the mucosa (ypT1a), 16.5% in the submucosa (ypT1b) and 6.4% only in lymph nodes (ypT0N+). Macroscopic residues in R0-specimens of partial responders (tumor regression grade 2-3: N = 90) were found in- and outside the gross tumor volume (GTV) in 33.3% and 8.9%, and only microscopic in- and outside the clinical target volume in 58.9% and 1.1%, respectively. Residual nodal disease was observed proximally and distally to the clinical target volume in 2 and 5 patients, respectively. Disease Free Survival decreased significantly if macroscopic tumor was outside the GTV and in ypT2-4aN+. CONCLUSIONS: After neoadjuvant chemoradiotherapy, pCR and ypT1aN0 were seen in a limited number of R0 resected specimens (19.8% and 7.3%, respectively), whereas 6.4% had only nodal disease (yT0N+). Disease Free Survival decreased significantly if macroscopic residue was outside the GTV and in responders with only nodal disease. Therefore, we should be cautious in applying wait and see strategies.


Assuntos
Quimiorradioterapia Adjuvante , Neoplasias Esofágicas , Quimiorradioterapia , Humanos , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasia Residual/patologia
3.
BMC Nurs ; 20(1): 135, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348725

RESUMO

BACKGROUND: Nursing care in hospitals increasingly involves older adults. A nursing workforce able to care for the ageing population is therefore critical for ensuring quality older adult care. Gaining insight in the knowledge and attitudes of nurses regarding older patients in the Netherlands is needed to develop and increase the impact of education- and quality improvement programs which can positively influence nurses' knowledge and attitudes regarding older patients. METHODS: A cross-sectional multicenter study was performed. Data was collected in ten tertiary medical teaching hospitals well spread across the Netherlands (89 wards, 2902 nurses). Knowledge levels were measured using the Knowledge about Older Patient-Quiz (KOP-Q), consisting of 30 true-false questions. Knowledge levels of registered nurses are compared with knowledge levels known from literature of first year nursing students; last year nursing students; nurses; and nurse specialist. Potential associated factors considered were: age; sex; education; experience; opinions and preferences. Opinion and preferences regarding working with older patients were measured by three questions: 1) which patient group nurses preferred to work with; 2) how nurses feel about the increase of older patients in the hospital; and 3) whether nurses find it difficult to care for older patients. RESULTS: From all wards, a representative sample of 1743 registered hospital nurses working on all 89 wards participated. On all wards, a large range in knowledge levels is observed between nurses, with 37% of nurses presenting knowledge levels comparable with nursing student and 31% of nurses presenting knowledge levels comparable with nurse specialists. Knowledge is related to age (p < .001), work experiences (p < .001), preparatory secondary education (p < .001) and nurses education level (p = .012). A minority (12.5%) prefers working with older patients and most nurses do not find it difficult. CONCLUSIONS: This study shows that there is a large diversity in knowledge levels of Dutch hospital nurses in every hospital, on every ward. A majority of nurses demonstrate negative opinions and preferences. This implies that older patients admitted can receive different levels of quality of care on the same day as nurses with different knowledge levels provide care during the various shifts. Findings demonstrate an urgent need for education programs with themes regarding essential care for older patients in the Netherlands.

4.
Genome Res ; 23(10): 1580-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23861385

RESUMO

The nuclear lamina is implicated in the organization of the eukaryotic nucleus. Association of nuclear lamins with the genome occurs through large chromatin domains including mostly, but not exclusively, repressed genes. How lamin interactions with regulatory elements modulate gene expression in different cellular contexts is unknown. We show here that in human adipose tissue stem cells, lamin A/C interacts with distinct spatially restricted subpromoter regions, both within and outside peripheral and intra-nuclear lamin-rich domains. These localized interactions are associated with distinct transcriptional outcomes in a manner dependent on local chromatin modifications. Down-regulation of lamin A/C leads to dissociation of lamin A/C from promoters and remodels repressive and permissive histone modifications by enhancing transcriptional permissiveness, but is not sufficient to elicit gene activation. Adipogenic differentiation resets a large number of lamin-genome associations globally and at subpromoter levels and redefines associated transcription outputs. We propose that lamin A/C acts as a modulator of local gene expression outcome through interaction with adjustable sites on promoters, and that these position-dependent transcriptional readouts may be reset upon differentiation.


Assuntos
Tecido Adiposo/citologia , Cromatina/metabolismo , Lamina Tipo A/metabolismo , Regiões Promotoras Genéticas , Células-Tronco/metabolismo , Transcrição Gênica , Adipogenia , Tecido Adiposo/metabolismo , Células Cultivadas , Perfilação da Expressão Gênica , Loci Gênicos , Humanos , Lamina Tipo A/genética , Lâmina Nuclear/genética , Lâmina Nuclear/metabolismo , Células-Tronco/citologia , Ativação Transcricional
5.
J Mater Sci Mater Med ; 24(3): 573-81, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23239262

RESUMO

An extension of the application of calcium phosphate cements (CPC) to load-bearing defects, e.g. in vertebroplasty, would require less brittle cements with an increased fracture toughness. Here we report the modification of CPC made of alpha-tricalcium phosphate (α-TCP) with 2-hydroxyethylmethacrylate (HEMA), which is polymerised during setting to obtain a mechanically stable polymer-ceramic composite with interpenetrating organic and inorganic networks. The cement liquid was modified by the addition of 30-70 % HEMA and ammoniumpersulfate/tetramethylethylendiamine as initiator. Modification of α-TCP cement paste with HEMA decreased the setting time from 14 min to 3-8 min depending on the initiator concentration. The 4-point bending strength was increased from 9 MPa to more than 14 MPa when using 50 % HEMA, while the bending modulus decreased from 18 GPa to approx. 4 GPa. The addition of ≥50 % HEMA reduced the brittle fracture behaviour of the cements and resulted in an increase of the work of fracture by more than an order of magnitude. X-ray diffraction analyses revealed that the degree of transformation of α-TCP to calcium deficient hydroxyapatite was lower for polymer modified cements (82 % for polymer free cement and 55 % for 70 % HEMA) after 24 h setting, while the polymerisation of HEMA in the cement liquid was quantitative according to FT-IR spectroscopy. This work demonstrated the feasibility of producing fracture resistant dual-setting calcium phosphate cements by adding water soluble polymerisable monomers to the liquid cement phase, which may be suitable for an application in load-bearing bone defects.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Proteins ; 75(4): 977-89, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19089956

RESUMO

Microbial beta-1,4-galactanases are glycoside hydrolases belonging to family 53, which degrade galactan and arabinogalactan side chains in the hairy regions of pectin, a major plant cell wall component. They belong to the larger clan GH-A of glycoside hydrolases, which cover many different poly- and oligosaccharidase specificities. Crystallographic complexes of Bacillus licheniformis beta-1,4-galactanase and its inactive nucleophile mutant have been obtained with methyl-beta(1-->4)-galactotetraoside, providing, for the first time, information on substrate binding to the aglycone side of the beta-1,4-galactanase substrate binding groove. Using the experimentally determined subsites as a starting point, a beta(1-->4)-galactononaose was built into the structure and subjected to molecular dynamics simulations giving further insight into the residues involved in the binding of the polysaccharide from subsite -4 to +5. In particular, this analysis newly identified a conserved beta-turn, which contributes to subsites -2 to +3. This beta-turn is unique to family 53 beta-1,4-galactanases among all clan GH-A families that have been structurally characterized and thus might be a structural signature for endo-beta-1,4-galactanase specificity.


Assuntos
Bacillus/enzimologia , Galactanos/química , Glicosídeo Hidrolases/química , Sequência de Aminoácidos , Sítios de Ligação , Configuração de Carboidratos , Simulação por Computador , Cristalografia por Raios X , Galactanos/metabolismo , Galactose/metabolismo , Glicosídeo Hidrolases/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Alinhamento de Sequência
7.
Mol Biol Cell ; 18(5): 1543-53, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17314394

RESUMO

Analyses of molecular events associated with reprogramming somatic nuclei to pluripotency are scarce. We previously reported the reprogramming of epithelial cells by extract of undifferentiated embryonal carcinoma (EC) cells. We now demonstrate reprogramming of DNA methylation and histone modifications on regulatory regions of the developmentally regulated OCT4 and NANOG genes by exposure of 293T cells to EC cell extract. OCT4 and NANOG are transcriptionally up-regulated and undergo mosaic cytosine-phosphate-guanosine demethylation. OCT4 demethylation occurs as early as week 1, is enhanced by week 2, and is most prominent in the proximal promoter and distal enhancer. Targeted OCT4 and NANOG demethylation does not occur in 293T extract-treated cells. Retinoic acid-mediated differentiation of reprogrammed cells elicits OCT4 promoter remethylation and transcriptional repression. Chromatin immunoprecipitation analyses of lysines K4, K9, and K27 of histone H3 on OCT4 and NANOG indicate that primary chromatin remodeling determinants are acetylation of H3K9 and demethylation of dimethylated H3K9. H3K4 remains di- and trimethylated. Demethylation of trimethylated H3K9 and H3K27 also occurs; however, trimethylation seems more stable than dimethylation. We conclude that a central epigenetic reprogramming event is relaxation of chromatin at loci associated with pluripotency to create a conformation compatible with transcriptional activation.


Assuntos
Carcinoma Embrionário/genética , Proteínas de Ligação a DNA/genética , Proteínas de Homeodomínio/genética , Fator 3 de Transcrição de Octâmero/genética , Acetilação , Carcinoma Embrionário/patologia , Linhagem Celular , Montagem e Desmontagem da Cromatina/genética , Metilação de DNA/efeitos dos fármacos , Epigênese Genética , Histonas/química , Histonas/metabolismo , Humanos , Técnicas In Vitro , Lisina/química , Metilação , Proteína Homeobox Nanog , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Sequências Reguladoras de Ácido Nucleico , Tretinoína/farmacologia , Células Tumorais Cultivadas , Regulação para Cima
8.
Biotechnol Prog ; 23(1): 100-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17269676

RESUMO

This study describes the identification of the key enzyme activities required in a "minimal" enzyme cocktail able to catalyze hydrolysis of water-soluble and water-insoluble wheat arabinoxylan and whole vinasse, a fermentation effluent resulting from industrial ethanol manufacture from wheat. The optimal arabinose-releasing and xylan-depolymerizing enzyme activities were identified from data obtained when selected, recombinant enzymes were systematically supplemented to the different arabinoxylan substrates in mixtures; this examination revealed three novel alpha-l-arabinofuranosidase activities: (i) one GH51 enzyme from Meripilus giganteus and (ii) one GH51 enzyme from Humicola insolens, both able to catalyze arabinose release from singly substituted xylose; and (iii) one GH43 enzyme from H. insolens able to catalyze the release of arabinose from doubly substituted xylose. Treatment of water-soluble and water-insoluble wheat arabinoxylan with an enzyme cocktail containing a 20%:20%:20%:40% mixture and a 25%:25%:25%:25% mixture, respectively, of the GH43 alpha-l-arabinofuranosidase from H. insolens (Abf II), the GH51 alpha-l-arabinofuranosidase from M. giganteus (Abf III), a GH10 endo-1,4-beta-xylanase from H. insolens (Xyl III), and a GH3 beta-xylosidase from Trichoderma reesei (beta-xyl) released 322 mg of arabinose and 512 mg of xylose per gram of water-soluble wheat arabinoxylan dry matter and 150 mg of arabinose and 266 mg of xylose per gram of water-insoluble wheat arabinoxylan dry matter after 24 h at pH 5, 50 degrees C. A 10%:40%:50% mixture of Abf II, Abf III, and beta-xyl released 56 mg of arabinose and 91 mg of xylose per gram of vinasse dry matter after 24 h at pH 5, 50 degrees C. The optimal dosages of the "minimal" enzyme cocktails were determined to be 0.4, 0.3, and 0.2 g enzyme protein per kilogram of substrate dry matter for the water-soluble wheat arabinoxylan, the water-insoluble wheat arabinoxylan, and the vinasse, respectively. These enzyme protein dosage levels were approximately 14, approximately 18, and approximately 27 times lower than the dosages used previously, when the same wheat arabinoxylan substrates were hydrolyzed with a combination of Ultraflo L and Celluclast 1.5 L, two commercially available enzyme preparations produced by H. insolens and T. reesei.


Assuntos
Endo-1,4-beta-Xilanases/química , Glicosídeo Hidrolases/química , Proteínas de Plantas/química , Triticum/metabolismo , Xilanos/química , Xilosidases/química , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Ativação Enzimática , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Hidrólise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Engenharia de Proteínas/métodos , Proteínas Recombinantes/química , Xilosidases/genética , Xilosidases/metabolismo
9.
Appl Microbiol Biotechnol ; 73(4): 850-61, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16944135

RESUMO

A novel alpha-L-arabinofuranosidase (alpha-AraF) belonging to glycoside hydrolase (GH) family 43 was cloned from Humicola insolens and expressed in Aspergillus oryzae. (1)H-NMR analysis revealed that the novel GH43 enzyme selectively hydrolysed (1-->3)-alpha-L-arabinofuranosyl residues of doubly substituted xylopyranosyl residues in arabinoxylan and in arabinoxylan-derived oligosaccharides. The optimal activity of the cloned enzyme was at pH 6.7 and 53 degrees C. Two other novel alpha-L-arabinofuranosidases (alpha-AraFs), both belonging to GH family 51, were cloned from H. insolens and from the white-rot basidiomycete Meripilus giganteus. Both GH51 enzymes catalysed removal of (1-->2) and (1-->3)-alpha-L-arabinofuranosyl residues from singly substituted xylopyranosyls in arabinoxylan; the highest arabinose yields were obtained with the M. giganteus enzyme. Combinations (50:50) of the GH43 alpha-AraF from H. insolens and the GH51 alpha-AraFs from either M. giganteus or H. insolens resulted in a synergistic increase in arabinose release from water-soluble wheat arabinoxylan in extended reactions at pH 6 and 40 degrees C. This synergistic interaction between GH43 and GH51 alpha-AraFs was also evident when a GH43 alpha-AraF from a Bifidobacterium sp. was supplemented in combination with either of the GH51 enzymes. The synergistic effect is presumed to be a result of the GH51 alpha-AraFs being able to catalyse the removal of single-sitting (1-->2)-alpha-L- arabinofuranosyls that resulted after the GH43 enzyme had catalysed the removal of (1-->3)-alpha-L-arabinofuranosyl residues on doubly substituted xylopyranosyls in the wheat arabinoxylan.


Assuntos
Ascomicetos/enzimologia , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/metabolismo , Xilanos/metabolismo , Sequência de Aminoácidos , Arabinose/metabolismo , Ascomicetos/genética , Aspergillus oryzae/genética , Bifidobacterium/enzimologia , Clonagem Molecular , Estabilidade Enzimática , Expressão Gênica , Glicosídeo Hidrolases/genética , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/metabolismo , Polyporales/enzimologia , Polyporales/genética , Alinhamento de Sequência , Especificidade por Substrato , Temperatura , Triticum
10.
Carbohydr Res ; 340(6): 1233-7, 2005 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-15797141

RESUMO

6''-alpha-Maltosyl-maltotriose and 6''-alpha-D-glucosyl-maltotriose were prepared from Novamyl degradation of 6-O-alpha-maltosyl-alpha-cyclodextrin and 6-O-alpha-D-glucosyl-alpha-cyclodextrin, respectively. NMR spectroscopy was used to elucidate their structural identities, in a combination of COSY experiments. Further, a mechanism for the degradation was proposed based on the Novamyl active site geometry.


Assuntos
Ciclodextrinas/química , Ciclodextrinas/metabolismo , Enzimas/metabolismo , Oligossacarídeos/biossíntese , Oligossacarídeos/metabolismo , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular
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