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1.
Circulation ; 147(20): 1518-1533, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37013819

RESUMO

BACKGROUND: Calcific aortic valve disease (CAVD) is characterized by a phenotypic switch of valvular interstitial cells to bone-forming cells. Toll-like receptors (TLRs) are evolutionarily conserved pattern recognition receptors at the interface between innate immunity and tissue repair. Type I interferons (IFNs) are not only crucial for an adequate antiviral response but also implicated in bone formation. We hypothesized that the accumulation of endogenous TLR3 ligands in the valvular leaflets may promote the generation of osteoblast-like cells through enhanced type I IFN signaling. METHODS: Human valvular interstitial cells isolated from aortic valves were challenged with mechanical strain or synthetic TLR3 agonists and analyzed for bone formation, gene expression profiles, and IFN signaling pathways. Different inhibitors were used to delineate the engaged signaling pathways. Moreover, we screened a variety of potential lipids and proteoglycans known to accumulate in CAVD lesions as potential TLR3 ligands. Ligand-receptor interactions were characterized by in silico modeling and verified through immunoprecipitation experiments. Biglycan (Bgn), Tlr3, and IFN-α/ß receptor alpha chain (Ifnar1)-deficient mice and a specific zebrafish model were used to study the implication of the biglycan (BGN)-TLR3-IFN axis in both CAVD and bone formation in vivo. Two large-scale cohorts (GERA [Genetic Epidemiology Research on Adult Health and Aging], n=55 192 with 3469 aortic stenosis cases; UK Biobank, n=257 231 with 2213 aortic stenosis cases) were examined for genetic variation at genes implicated in BGN-TLR3-IFN signaling associating with CAVD in humans. RESULTS: Here, we identify TLR3 as a central molecular regulator of calcification in valvular interstitial cells and unravel BGN as a new endogenous agonist of TLR3. Posttranslational BGN maturation by xylosyltransferase 1 (XYLT1) is required for TLR3 activation. Moreover, BGN induces the transdifferentiation of valvular interstitial cells into bone-forming osteoblasts through the TLR3-dependent induction of type I IFNs. It is intriguing that Bgn-/-, Tlr3-/-, and Ifnar1-/- mice are protected against CAVD and display impaired bone formation. Meta-analysis of 2 large-scale cohorts with >300 000 individuals reveals that genetic variation at loci relevant to the XYLT1-BGN-TLR3-interferon-α/ß receptor alpha chain (IFNAR) 1 pathway is associated with CAVD in humans. CONCLUSIONS: This study identifies the BGN-TLR3-IFNAR1 axis as an evolutionarily conserved pathway governing calcification of the aortic valve and reveals a potential therapeutic target to prevent CAVD.


Assuntos
Estenose da Valva Aórtica , Calcinose , Adulto , Animais , Humanos , Camundongos , Valva Aórtica/patologia , Estenose da Valva Aórtica/patologia , Biglicano/metabolismo , Calcinose/metabolismo , Células Cultivadas , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Peixe-Zebra
2.
J Am Heart Assoc ; 11(20): e026076, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36216458

RESUMO

Background Spinal cord ischemia (SCI) remains a devastating complication after aortic dissection or repair. A primary hypoxic damage is followed by a secondary damage resulting in further cellular loss via apoptosis. Affected patients have a poor prognosis and limited therapeutic options. Shock wave therapy (SWT) improves functional outcome, neuronal degeneration and survival in murine spinal cord injury. In this first-in-human study we treated 5 patients with spinal cord ischemia with SWT aiming to prove safety and feasibility. Methods and Results Human neurons were subjected to ischemic injury with subsequent SWT. Reactive oxygen species and cellular apoptosis were quantified using flow cytometry. Signaling of the antioxidative transcription factor NRF2 (nuclear factor erythroid 2-related factor 2) and immune receptor Toll-like receptor 3 (TLR3) were analyzed. To assess whether SWT act via a conserved mechanism, transgenic tlr3-/- zebrafish created via CRISPR/Cas9 were subjected to spinal cord injury. To translate our findings into a clinical setting, 5 patients with SCI underwent SWT. Baseline analysis and follow-up (6 months) included assessment of American Spinal Cord Injury Association (ASIA) impairment scale, evaluation of Spinal Cord Independence Measure score and World Health Organization Quality of Life questionnaire. SWT reduced the number of reactive oxygen species positive cells and apoptosis upon ischemia via induction of the antioxidative factor nuclear factor erythroid 2-related factor 2. Inhibition or deletion of tlr3 impaired axonal growth after spinal cord lesion in zebrafish, whereas tlr3 stimulation enhanced spinal regeneration. In a first-in-human study, we treated 5 patients with SCI using SWT (mean age, 65.3 years). Four patients presented with acute aortic dissection (80%), 2 of them exhibited preoperative neurological symptoms (40%). Impairment was ASIA A in 1 patient (20%), ASIA B in 3 patients (60%), and ASIA D in 1 patient (20%) at baseline. At follow-up, 2 patients were graded as ASIA A (40%) and 3 patients as ASIA B (60%). Spinal cord independence measure score showed significant improvement. Examination of World Health Organization Quality of Life questionnaires revealed increased scores at follow-up. Conclusions SWT reduces oxidative damage upon SCI via immune receptor TLR3. The first-in-human application proved safety and feasibility in patients with SCI. SWT could therefore become a powerful regenerative treatment option for this devastating injury.


Assuntos
Dissecção Aórtica , Tratamento por Ondas de Choque Extracorpóreas , Traumatismos da Medula Espinal , Isquemia do Cordão Espinal , Humanos , Camundongos , Animais , Idoso , Receptor 3 Toll-Like/metabolismo , Receptor 3 Toll-Like/uso terapêutico , Fator 2 Relacionado a NF-E2 , Peixe-Zebra , Estudos de Viabilidade , Espécies Reativas de Oxigênio , Qualidade de Vida , Isquemia do Cordão Espinal/etiologia , Isquemia do Cordão Espinal/prevenção & controle , Isquemia do Cordão Espinal/patologia , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Medula Espinal/metabolismo , Estresse Oxidativo , Isquemia , Dissecção Aórtica/patologia
3.
Mol Metab ; 54: 101329, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34454092

RESUMO

OBJECTIVE: The loss of forkhead box protein O1 (FoxO1) signaling in response to metabolic stress contributes to the etiology of type II diabetes, causing the dedifferentiation of pancreatic beta cells to a cell type reminiscent of endocrine progenitors. Lack of methods to easily model this process in vitro, however, have hindered progress into the identification of key downstream targets and potential inhibitors. We therefore aimed to establish such an in vitro cellular dedifferentiation model and apply it to identify novel agents involved in the maintenance of beta-cell identity. METHODS: The murine beta-cell line, Min6, was used for primary experiments and high-content screening. Screens encompassed a library of small-molecule drugs representing the chemical and target space of all FDA-approved small molecules with an automated immunofluorescence readout. Validation experiments were performed in a murine alpha-cell line as well as in primary murine and human diabetic islets. Developmental effects were studied in zebrafish and C. elegans models, while diabetic db/db mouse models were used to elucidate global glucose metabolism outcomes. RESULTS: We show that short-term pharmacological FoxO1 inhibition can model beta-cell dedifferentiation by downregulating beta-cell-specific transcription factors, resulting in the aberrant expression of progenitor genes and the alpha-cell marker glucagon. From a high-content screen, we identified loperamide as a small molecule that can prevent FoxO inhibitor-induced glucagon expression and further stimulate insulin protein processing and secretion by altering calcium levels, intracellular pH, and FoxO1 localization. CONCLUSIONS: Our study provides novel models, molecular targets, and drug candidates for studying and preventing beta-cell dedifferentiation.


Assuntos
Proteína Forkhead Box O1/metabolismo , Glucagon/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Adulto , Animais , Desdiferenciação Celular , Células Cultivadas , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade
4.
Development ; 148(4)2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33531430

RESUMO

Hedgehog (Hh) ligands act as morphogens to direct patterning and proliferation during embryonic development. Protein kinase A (PKA) is a central negative regulator of Hh signalling, and in the absence of Hh ligands, PKA activity prevents inappropriate expression of Hh target genes. The orphan G-protein-coupled receptor Gpr161 contributes to the basal Hh repression machinery by activating PKA. Gpr161 acts as an A-kinase-anchoring protein, and is itself phosphorylated by PKA, but the functional significance of PKA phosphorylation of Gpr161 in the context of Hh signalling remains unknown. Here, we show that loss of Gpr161 in zebrafish leads to constitutive activation of medium and low, but not maximal, levels of Hh target gene expression. Furthermore, we find that PKA phosphorylation-deficient forms of Gpr161, which we show directly couple to Gαs, display an increased sensitivity to Shh, resulting in excess high-level Hh signalling. Our results suggest that PKA feedback-mediated phosphorylation of Gpr161 may provide a mechanism for fine-tuning Gpr161 ciliary localisation and PKA activity.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Retroalimentação Fisiológica , Proteínas Hedgehog/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Peixe-Zebra/fisiologia , Animais , Evolução Biológica , Cílios/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Desenvolvimento Embrionário/genética , Proteínas Hedgehog/genética , Mutação , Fenótipo , Receptores Acoplados a Proteínas G/genética
5.
JCI Insight ; 5(15)2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32759498

RESUMO

Spinal cord injury (SCI) remains a devastating condition with poor prognosis and very limited treatment options. Affected patients are severely restricted in their daily activities. Shock wave therapy (SWT) has shown potent regenerative properties in bone fractures, wounds, and ischemic myocardium via activation of the innate immune receptor TLR3. Here, we report on the efficacy of SWT for regeneration of SCI. SWT improved motor function and decreased lesion size in WT but not Tlr3-/- mice via inhibition of neuronal degeneration and IL6-dependent recruitment and differentiation of neuronal progenitor cells. Both SWT and TLR3 stimulation enhanced neuronal sprouting and improved neuronal survival, even in human spinal cord cultures. We identified tlr3 as crucial enhancer of spinal cord regeneration in zebrafish. Our findings indicate that TLR3 signaling is involved in neuroprotection and spinal cord repair and suggest that TLR3 stimulation via SWT could become a potent regenerative treatment option.


Assuntos
Tratamento por Ondas de Choque Extracorpóreas/métodos , Neovascularização Fisiológica , Neurônios/citologia , Fármacos Neuroprotetores , Traumatismos da Medula Espinal/terapia , Regeneração da Medula Espinal , Receptor 3 Toll-Like/fisiologia , Animais , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora , Neurônios/metabolismo , Traumatismos da Medula Espinal/etiologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Peixe-Zebra
6.
Front Chem ; 7: 268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31119122

RESUMO

The expansion of renewable energy and the growing number of electric vehicles and mobile devices are demanding improved and low-cost electrochemical energy storage. In order to meet the future needs for energy storage, novel material systems with high energy densities, readily available raw materials, and safety are required. Currently, lithium and lead mainly dominate the battery market, but apart from cobalt and phosphorous, lithium may show substantial supply challenges prospectively, as well. Therefore, the search for new chemistries will become increasingly important in the future, to diversify battery technologies. But which materials seem promising? Using a selection algorithm for the evaluation of suitable materials, the concept of a rechargeable, high-valent all-solid-state aluminum-ion battery appears promising, in which metallic aluminum is used as the negative electrode. On the one hand, this offers the advantage of a volumetric capacity four times higher (theoretically) compared to lithium analog. On the other hand, aluminum is the most abundant metal in the earth's crust. There is a mature industry and recycling infrastructure, making aluminum very cost efficient. This would make the aluminum-ion battery an important contribution to the energy transition process, which has already started globally. So far, it has not been possible to exploit this technological potential, as suitable positive electrodes and electrolyte materials are still lacking. The discovery of inorganic materials with high aluminum-ion mobility-usable as solid electrolytes or intercalation electrodes-is an innovative and required leap forward in the field of rechargeable high-valent ion batteries. In this review article, the constraints for a sustainable and seminal battery chemistry are described, and we present an assessment of the chemical elements in terms of negative electrodes, comprehensively motivate utilizing aluminum, categorize the aluminum battery field, critically review the existing positive electrodes and solid electrolytes, present a promising path for the accelerated development of novel materials and address problems of scientific communication in this field.

7.
Breast Cancer Res Treat ; 175(3): 701-712, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30868393

RESUMO

PURPOSE: Quality of life (QoL) plays an important role in recovery-especially after an incisive diagnosis such as breast cancer. Here, we present a comprehensive assessment of QoL for pre- and postmenopausal patients, starting from initial systemic treatment of early breast cancer until 3 years later, in patients from a so-called "real-world" setting. METHODS: 251 premenopausal and 478 postmenopausal patients with early breast cancer have been recruited into the longitudinal MaLife project within the prospective, multicentre, German Tumour Registry Breast Cancer between 2011 and 2015. The questionnaires FACT-G, FACT-Taxane, FACT-ES, EORTC QLQ-BR23, BFI and HADS were filled in at start of treatment (T0), 6, 12, 24 and 36 months later. The proportion of patients with clinically meaningful changes at 36 months was determined. RESULTS: This first interim analysis shows that the FACT-G global QoL improved over time regardless of the menopausal status. However, clinically meaningful decrease of social/family well-being (48-51%), arm symptoms (44-49%) and symptoms of neurotoxicity (55-56%) was frequently reported 3 years after start of treatment. Many premenopausal patients also reported a clinically meaningful worsening of endocrine symptoms (64%), emotional well-being (36%) and fatigue intensity (37%). Additionally, 3 years after start of treatment, 15% of the patients were classified as doubtful cases and 18% as definite cases of anxiety. CONCLUSIONS: Despite improvements in global QoL, breast cancer survivors report worsened ailments 3 years after start of therapy. Follow-up care should distinguish between premenopausal patients needing special attention for emotional/menopausal issues, and postmenopausal patients needing particular care regarding physical concerns.


Assuntos
Neoplasias da Mama/terapia , Pós-Menopausa/psicologia , Pré-Menopausa/psicologia , Qualidade de Vida/psicologia , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/psicologia , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Adulto Jovem
8.
Development ; 145(3)2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29386244

RESUMO

The three-dimensional architecture of the pancreatic islet is integral to beta cell function, but the process of islet formation remains poorly understood due to the difficulties of imaging internal organs with cellular resolution. Within transparent zebrafish larvae, the developing pancreas is relatively superficial and thus amenable to live imaging approaches. We performed in vivo time-lapse and longitudinal imaging studies to follow islet development, visualizing both naturally occurring islet cells and cells arising with an accelerated timecourse following an induction approach. These studies revealed previously unappreciated fine dynamic protrusions projecting between neighboring and distant endocrine cells. Using pharmacological compound and toxin interference approaches, and single-cell analysis of morphology and cell dynamics, we determined that endocrine cell motility is regulated by phosphoinositide 3-kinase (PI3K) and G-protein-coupled receptor (GPCR) signaling. Linking cell dynamics to islet formation, perturbation of protrusion formation disrupted endocrine cell coalescence, and correlated with decreased islet cell differentiation. These studies identified novel cell behaviors contributing to islet morphogenesis, and suggest a model in which dynamic exploratory filopodia establish cell-cell contacts that subsequently promote cell clustering.


Assuntos
Ilhotas Pancreáticas/crescimento & desenvolvimento , Ilhotas Pancreáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Citoesqueleto de Actina/metabolismo , Animais , Animais Geneticamente Modificados , Agregação Celular , Movimento Celular , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Ilhotas Pancreáticas/citologia , Queratina-18/genética , Queratina-18/metabolismo , Organogênese , Inibidores de Fosfoinositídeo-3 Quinase , Pseudópodes/metabolismo , Pseudópodes/ultraestrutura , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Análise de Célula Única , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores , Proteínas rac1 de Ligação ao GTP/metabolismo
9.
Eur J Haematol ; 100(5): 455-464, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29393986

RESUMO

OBJECTIVES: This study was conducted to investigate the real-world effectiveness and tolerability of rituximab-containing chemoimmunotherapies, which have become the standard of care for chronic lymphocytic leukaemia (CLL), particularly for physically fit patients. Furthermore, current treatment patterns in clinical practice were documented, and an unselected real-life population was compared with older, comorbid patients. METHODS: Prospective, multicentre, observational study with rituximab-containing chemoimmunotherapy in CLL patients. RESULTS: Of 681 patients in total, 485 were enroled in cohort 1 (unselected) and 196 in cohort 2 (comorbid "slow-go" patients). The median patient age was higher than in most randomised controlled trials (cohort 1: 70 years and cohort 2: 75 years). The most common treatment regimen in both first-line and relapsed patients was rituximab-bendamustine. Two-year progression-free survival rate for first-line therapy was 84.1% for cohort 1 and 69.8% for cohort 2 (with best overall response rate 81.8% for cohort 1 and 76.6% for cohort 2). General and B-symptoms declined during treatment and remained at low level or decreased further until study end. The safety profile observed in randomised clinical trials was confirmed. CONCLUSION: Chemoimmunotherapy with rituximab is feasible and safe in a wide variety of clinical settings in CLL, including the treatment of older patients with comorbidities (ClinicalTrials.gov NCT01178086).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Recidiva , Rituximab/administração & dosagem , Análise de Sobrevida , Resultado do Tratamento
10.
Breast Cancer ; 25(3): 275-283, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29204847

RESUMO

BACKGROUND: Several regimens for which efficacy was established in randomized controlled trials are recommended in current treatment guidelines for early breast cancer. However, knowledge on use and effectiveness of commonly administered chemotherapeutic agents in real-life care and across all breast cancer subtypes is limited. METHODS: The prospective, multicentre German TMK cohort study (Tumour Registry Breast Cancer) recruited patients in 148 oncology outpatient-centres. Data from 1650 patients who completed adjuvant chemotherapy were analysed regarding treatment regimens and taxane use from 2007 to 2014. The association of patient characteristics with application of taxane-free regimens was examined with a multivariate regression model. RESULTS: The preferred adjuvant treatment shifted from fluorouracil, anthracycline and cyclophosphamide containing regimens to anthracycline/taxane combinations. Taxane use increased for all subtypes, and the greatest rise was among node-negative patients. Older age, node-negativity, lower grading, HR-positive/HER2-negative subtype and earlier start year of therapy were significantly associated with taxane-free therapy. CONCLUSIONS: Treatment with anthracycline/taxane-based chemotherapy in Germany has been rising for every subtype. The increased taxane use reflects updated guideline recommendations over the past decade. Cohort studies like the TMK provide insight into real-life treatment of patients outside of clinical trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Sistema de Registros/estatística & dados numéricos , Fatores Etários , Idoso , Assistência Ambulatorial/estatística & dados numéricos , Assistência Ambulatorial/tendências , Antraciclinas/uso terapêutico , Neoplasias da Mama/patologia , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Quimioterapia Adjuvante/métodos , Feminino , Alemanha/epidemiologia , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxoides/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
11.
Dtsch Med Wochenschr ; 141(18): 1325-9, 2016 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-27519008

RESUMO

Nodular disease of the thyroid is a very common disorder with which colleagues from all disciplines are frequently confronted. Particularly for patients with benign thyroid nodules or cystic lesions the expenditure and risks of standardly performed thyroidectomy stands in discrepancy with the clinical harmlessness of the disease. For this reason we would like to give an overview of possible non-surgical alternatives in the therapy of benign thyroid nodules and cysts, if they cause unpleasant symptoms.


Assuntos
Técnicas de Ablação , Nódulo da Glândula Tireoide/terapia , Humanos , Tireoidectomia
12.
PLoS One ; 10(12): e0145178, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26695815

RESUMO

Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive soft-tissue sarcomas, characterized by complex karyotypes. The molecular bases of such malignancy are poorly understood and efficient targeted molecular therapies are currently lacking. Here we describe a novel zebrafish model of MPNSTs, represented by the transgenic mutant line Tg(-8.5nkx2.2a:GFP)ia2. ia2 homozygous animals displayed embryonic lethality by 72 hpf, while the heterozygotes develop visible tumor masses with high frequency in adulthood. Histological and immunohistochemical examination revealed aggressive tumors with either mesenchymal or epithelial features. The former (54% of the cases) arose either in the abdominal cavity, or as intrathecal/intraspinal lesions and is composed of cytokeratin-negative spindle cells with fascicular/storiform growth pattern consistent with zebrafish MPNSTs. The second histotype was composed by polygonal or elongated cells, immunohistochemically positive for the pan-cytokeratin AE1/AE3. The overall histologic and immunohistochemical features were consistent with a malignant epithelial neoplasm of possible gastrointestinal/pancreatic origin. With an integrated approach, based on microsatellite (VNTR) and STS markers, we showed that ia2 insertion, in Tg(-8.5nkx2.2a:GFP)ia2 embryos, is associated with a deletion of 15.2 Mb in the telomeric portion of chromosome 1. Interestingly, among ia2 deleted genes we identified the presence of the 40S ribosomal protein S6 gene that may be one of the possible drivers for the MPNSTs in ia2 mutants. Thanks to the peculiar features of zebrafish as animal model of human cancer (cellular and genomic similarity, transparency and prolificacy) and the GFP tag, the Tg(-8.5nkx2.2a:GFP)ia2 line provides a manageable tool to study in vivo with high frequency MPNST biology and genetics, and to identify, in concert with the existing zebrafish MPNST models, conserved relevant mechanisms in zebrafish and human cancer development.


Assuntos
Animais Geneticamente Modificados , Deleção Cromossômica , Cromossomos , Neoplasias Experimentais , Neoplasias de Bainha Neural , Peixe-Zebra , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Cromossomos/genética , Cromossomos/metabolismo , Proteínas de Fluorescência Verde , Humanos , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias de Bainha Neural/genética , Neoplasias de Bainha Neural/metabolismo , Neoplasias de Bainha Neural/patologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
13.
Hematol Oncol ; 33(1): 15-22, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24733536

RESUMO

Various treatment options exist for patients with chronic lymphocytic leukaemia (CLL). Clinical registries provide insight into routine treatment and identify changes in treatment over time. The Tumour Registry Lymphatic Neoplasms prospectively collects data on the treatment of patients with lymphoid B-cell neoplasm as administered by office-based haematologists in Germany. Data on patient and tumour characteristics, co-morbidities, systemic treatments, and outcome parameters are recorded. Eight hundred and six patients with CLL were recruited between May 2009 and August 2013. At the start of first-line treatment, median age was 71 years, 64% were male, and 44% had a Binet stage C disease. The most frequently used first-line/second-line regimens were bendamustine + rituximab (BR, 56%/55%), fludarabine + cyclophosphamide + rituximab (FCR, 22%/11%), and bendamustine (B, 5%/9%). Chlorambucil was used in only 7% (first-line) and 6% (second-line) of patients. Patients treated with FCR were younger and healthier than patients treated with BR. Overall, 91% of first-line treatments were successful (40% complete response). Real-life patient populations differ considerably from patients treated in randomized controlled trials. BR and FCR dominate the first-line and second-line treatments of CLL by office-based haematologists in Germany. Future analysis will investigate progression-free and overall survival times.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Sistema de Registros/estatística & dados numéricos , Anticorpos Monoclonais Murinos/administração & dosagem , Cloridrato de Bendamustina , Clorambucila/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Alemanha , Hematologia/métodos , Hematologia/estatística & dados numéricos , Humanos , Masculino , Compostos de Mostarda Nitrogenada/administração & dosagem , Visita a Consultório Médico/estatística & dados numéricos , Prednisona/administração & dosagem , Estudos Prospectivos , Rituximab , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
14.
Dev Biol ; 396(1): 81-93, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25286120

RESUMO

TGF-beta (TGFß) family mediated Smad signaling is involved in mesoderm and endoderm specifications, left-right asymmetry formation and neural tube development. The TGFß1/2/3 and Activin/Nodal signal transduction cascades culminate with activation of SMAD2 and/or SMAD3 transcription factors and their overactivation are involved in different pathologies with an inflammatory and/or uncontrolled cell proliferation basis, such as cancer and fibrosis. We have developed a transgenic zebrafish reporter line responsive to Smad3 activity. Through chemical, genetic and molecular approaches we have seen that this transgenic line consistently reproduces in vivo Smad3-mediated TGFß signaling. Reporter fluorescence is activated in phospho-Smad3 positive cells and is responsive to both Smad3 isoforms, Smad3a and 3b. Moreover, Alk4 and Alk5 inhibitors strongly repress the reporter activity. In the CNS, Smad3 reporter activity is particularly high in the subpallium, tegumentum, cerebellar plate, medulla oblongata and the retina proliferative zone. In the spinal cord, the reporter is activated at the ventricular zone, where neuronal progenitor cells are located. Colocalization methods show in vivo that TGFß signaling is particularly active in neuroD+ precursors. Using neuronal transgenic lines, we observed that TGFß chemical inhibition leads to a decrease of differentiating cells and an increase of proliferation. Similarly, smad3a and 3b knock-down alter neural differentiation showing that both paralogues play a positive role in neural differentiation. EdU proliferation assay and pH3 staining confirmed that Smad3 is mainly active in post-mitotic, non-proliferating cells. In summary, we demonstrate that the Smad3 reporter line allows us to follow in vivo Smad3 transcriptional activity and that Smad3, by controlling neural differentiation, promotes the progenitor to precursor switch allowing neural progenitors to exit cell cycle and differentiate.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteína Smad3/genética , Medula Espinal/embriologia , Fator de Crescimento Transformador beta/metabolismo , Transgenes , Proteínas de Peixe-Zebra/genética , Receptores de Ativinas Tipo I/metabolismo , Animais , Animais Geneticamente Modificados , Ciclo Celular , Proliferação de Células , Genes Reporter , Imuno-Histoquímica , Neurônios/metabolismo , Fenótipo , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Medula Espinal/fisiologia , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
15.
Proc Natl Acad Sci U S A ; 109(42): 16945-50, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23027928

RESUMO

Collective cell migration is key to morphogenesis, wound healing, or cancer cell migration. However, its cellular bases are just starting to be unraveled. During vertebrate gastrulation, axial mesendoderm migrates in a group, the prechordal plate, from the embryonic organizer to the animal pole. How this collective migration is achieved remains unclear. Previous work has suggested that cells migrate as individuals, with collective movement resulting from the addition of similar individual cell behavior. Through extensive analyses of cell trajectories, morphologies, and polarization in zebrafish embryos, we reveal that all prechordal plate cells show the same behavior and rely on the same signaling pathway to migrate, as expected if they do so individually. However, by using cell transplants, we demonstrate that prechordal plate migration is a true collective process, as isolated cells do not migrate toward the animal pole. They are still polarized and motile but lose directionality. Directionality is restored upon contact with the endogenous prechordal plate. This contact dependent orientation relies on E-cadherin, Wnt-PCP signaling, and Rac1. Importantly, groups of cells also need contact with the endogenous plate to orient correctly, showing an instructive role of the plate in establishing directionality. Overall, our results lead to an original model of collective migration in which directional information is contained within the moving group rather than provided by extrinsic cues, and constantly maintained in cells by contacts with their neighbors. This self-organizing model could account for collective invasion of new territories, as observed in cancer strands, without requirement for any attractant in the colonized tissue.


Assuntos
Movimento Celular/fisiologia , Endoderma/fisiologia , Mesoderma/fisiologia , Morfogênese/fisiologia , Transdução de Sinais/fisiologia , Animais , Caderinas/metabolismo , Polaridade Celular/fisiologia , Endoderma/citologia , Hibridização In Situ , Mesoderma/citologia , Imagem com Lapso de Tempo , Via de Sinalização Wnt/fisiologia , Peixe-Zebra
16.
J Biomed Opt ; 16(8): 086002, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21895314

RESUMO

We investigate the use of a frequency-domain reconstruction algorithm based on the nonuniform fast Fourier transform (NUFFT) for photoacoustic imaging (PAI). Standard algorithms based on the fast Fourier transform (FFT) are computationally efficient, but compromise the image quality by artifacts. In our previous work we have developed an algorithm for PAI based on the NUFFT which is computationally efficient and can reconstruct images with the quality known from temporal backprojection algorithms. In this paper we review imaging qualities, such as resolution, signal-to-noise ratio, and the effects of artifacts in real-world situations. Reconstruction examples show that artifacts are reduced significantly. In particular, image details with a larger distance from the detectors can be resolved more accurately than with standard FFT algorithms.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Técnicas Fotoacústicas/métodos , Animais , Artefatos , Embrião não Mamífero/anatomia & histologia , Feminino , Análise de Fourier , Camundongos , Neoplasias/patologia , Imagens de Fantasmas , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Suturas , Peixe-Zebra/anatomia & histologia
17.
Gene Expr Patterns ; 11(8): 491-500, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21889616

RESUMO

Dickkopf (dkk) genes belong to the family of secreted wnt-inhibitors with conserved cysteine-rich domains. In contrast to the prototype dkk1, dkk3 does not modulate canonical Wnt/ß-catenin signalling. Until now, neither functions nor interaction partners of dkk3 in lower vertebrates have been described. In this study we cloned two dkk3 homologues dkk3a(dkk3l) and dkk3b(dkk3) and a dkk1 homologue dkk1a of the zebrafish and studied their expression patterns during embryonic development in comparison to the known dkk1b gene. Moreover, mutants with defects in hedgehog signalling (smo), notch (mib) signalling, nodal signalling (Zoep) or retinoic acid synthesis (neckless) were analyzed for changes in dkk3 gene expression. In situ hybridization analyses showed a dynamic expression of dkk1a and dkk1b primarily in epidermal structures of the otic vesicle, lens, branchial arches and fin folds. While dkk1a was expressed mainly in deep tissues, dkk1b expression was mainly found in protrusions at the outer surface of the branchial arch epidermis. In contrast, dkk3 genes showed expression in different tissues. Strong signals for dkk3a(dkk3l) were present in various neuronal structures of the head, whereas dkk3b(dkk3) expression was restricted mainly to endocrine cells of the pancreas and to the brachial arches. In summary, both dkk3 genes display a unique and distinct expression pattern in late embryonic development, pointing to a specific role during neuronal and pancreatic cell differentiation.


Assuntos
Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Proteínas de Peixe-Zebra/biossíntese , Peixe-Zebra/embriologia , Animais , Diferenciação Celular/fisiologia , Embrião não Mamífero/citologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação , Especificidade de Órgãos/fisiologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
18.
Pflege Z ; 63(11): 680-3, 2010 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-21086675

RESUMO

Due to demographic and social developments nursing service will continueto be a growth industry in the long run. The requirement for this is the political volition of a sufficient funding. A minimum wage in nursing service tends to increase prices of the offered services. Stated justifications for a minimum wage are wage dumping protection (inter alia against the background of the upcoming opening of the single market in 2011) as well as raising rivals' costs. Protection is focused on the 266,000 non-skilled workers in basic care owing to the strong tightening of the labour market for caregivers. Operative minimum wages will lead to adjustments by optimising operations, intensification of work, and rationalisation of workflow by increased employment of capital as well as technical substitution of relatively expensive non-skilled workers. In addition there will be increased pressure on prices for nursing services and private co-payments. There will be an increased supply and demand for illegal services. Suppliers who had been tied to collective contracts so far will achieve a relative advantage in competition.


Assuntos
Financiamento Governamental/economia , Seguro de Serviços de Enfermagem/economia , Programas Nacionais de Saúde/economia , Recursos Humanos de Enfermagem/economia , Salários e Benefícios/legislação & jurisprudência , Custos e Análise de Custo , Financiamento Pessoal/economia , Previsões , Alemanha , Serviços de Assistência Domiciliar/economia , Humanos , Dinâmica Populacional , Garantia da Qualidade dos Cuidados de Saúde/economia
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