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1.
J Child Lang ; : 1-33, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752409

RESUMO

Children up to school age are known to have difficulty comprehending complex sentences with temporal connectives, but the reasons remain controversial. We tested six- to twelve-year-old children to assess how the iconicity of event-language mapping, type of connective, and clause order mediate the comprehension of temporal sentences. Sixty monolingual Greek-speaking children and 15 adult controls completed a picture-sequence selection task in which they judged after- and before-sentences in iconic and non-iconic order. Up to age twelve, children did not reach full adult-like comprehension of the connectives; performance in non-iconic after-sentences was significantly lower than in the other three conditions across all ages. We conclude that neither iconicity, connective, nor clause order can fully explain these findings and propose an account based on the interaction of iconicity and clause order: non-iconic, sentence-medial after requires revision of the initial event representation, resulting in an event-semantic kindergarten-path that children find difficult to overcome.

2.
PLoS One ; 18(11): e0294608, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38011175

RESUMO

A growing body of evidence suggests that news media which includes a sympathetic portrayal of a mother bereaved by substance use can increase public support for harm reduction initiatives. However, the extent to which such news media coverage occurs in Canada is unknown, and research has not documented how the news media in Canada covers such stories. We undertook a mixed-method secondary analyses of 5681 Canadian newspaper articles on harm reduction (2000-2016). Quantitative analyses described the volume and content of harm reduction reporting featuring a mother whose child's death was related to substance use while qualitative thematic analysis provided in-depth descriptions of the discourses underlying such news reporting. Newspaper articles featuring a mother whose child's death was related to substance use were rarely published (n = 63; 1.1% of total harm reduction media coverage during the study period). Deductive content analysis of these 63 texts revealed that coverage of naloxone distribution (42.9%) and supervised drug consumption services (28.6%) were prioritized over other harm reduction services. Although harm reduction (services or policies) were advocated by the mother in most (77.8%) of these 63 texts, inductive thematic analysis of a subset (n = 52) of those articles revealed that mothers' advocacy was diminished by newspaper reporting that emphasized their experiences of grief, prioritized individual biographies over structural factors contributing to substance use harms, and created rhetorical divisions between different groups of people who use drugs (PWUD). Bereaved mothers' advocacy in support of harm reduction programs and services may be minimized in the process of reporting their stories for newspaper readers. Finding ways to report bereaved mothers' stories in ways that are inclusive of all PWUD while highlighting the role of broad, structural determinants of substance use has the potential to shift public opinion and government support in favour of these life-saving services.


Assuntos
Redução do Dano , Transtornos Relacionados ao Uso de Substâncias , Criança , Feminino , Humanos , Mães , Canadá , Meios de Comunicação de Massa
3.
Drug Alcohol Rev ; 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608430

RESUMO

Canada is in the midst of a public health emergency in drug poisoning (overdose) deaths. In this context parents, and especially mothers, of those who have died from drug poisoning have mobilised to advocate for urgent responses and drug policy reforms. To document this emerging women-led advocacy, we initiated a community-academic research partnership with three parent groups representing families in Canada bereaved by drug-related deaths. In this commentary, we describe four guiding principles we developed during the course of this project, to ensure an ethical and equitable approach to conducting our research partnership. In particular, we emphasise how we navigated parents' roles as vocal advocates for addressing drug stigma and expanding harm reduction while actively working to avoid eclipsing the need to centre the perspectives of people who use drugs. Meaningful and collaborative partnerships between academics and community groups may facilitate greater understandings of how families and communities can be allied in drug policy reforms urgently needed to prevent drug poisoning deaths.

4.
PLoS One ; 18(8): e0290571, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37647278

RESUMO

BACKGROUND: Variable fibrinogen content within cryoprecipitate makes accurate dosing challenging in patients with coagulopathic bleeding, in addition to pathogen transmission risks associated with its administration. Purified and standardized human fibrinogen concentrates (HFCs) represent reliable alternatives. Full cryoprecipitate characterization is required to inform selection of an appropriate fibrinogen source for supplementation therapy. METHODS: Extended biochemical comparison of pooled cryoprecipitate and HFC (Fibryga, Octapharma) was performed using commercially available assays to determine levels of variability in cryoprecipitate and HFC. In addition to standard procoagulant factors, measurements included activities of platelet-derived microparticles (PMPs) and plasminogen, and levels of fibrin degradation products. RESULTS: Cryoprecipitate contains lower fibrinogen levels than HFC (4.83 vs.19.73 g/L; p<0.001), translating to approximately half the amount of fibrinogen per standard cryoprecipitate dose (two pools, pre-pooled from five donations each) vs. HFC (2.14 vs. 3.95 g; p<0.001). Factor XIII (FXIII) levels were also lower in cryoprecipitate vs. HFC (192.17 vs. 328.33 IU/dL; p = 0.002). Levels of procoagulants in cryoprecipitate, such as von Willebrand Factor (VWF) and factor VIII (FVIII), were highly variable, as was PMP activity. A standard cryoprecipitate dose contains significantly higher levels of measured plasminogen and D-dimer fragments than a standard HFC dose. CONCLUSION: The tested HFC is a more reliable fibrinogen and FXIII source for accurate dosing compared with cryoprecipitate. Cryoprecipitate appears considerably less predictable for bleeding management due to wide variation in pro- and anticoagulation factors, the presence of PMPs, and the potential to elevate VWF and FVIII to prothrombotic levels.


Assuntos
Micropartículas Derivadas de Células , Fármacos Hematológicos , Hemostáticos , Humanos , Fibrinogênio , Fator de von Willebrand , Coagulação Sanguínea , Serina Proteases
5.
Qual Health Res ; 31(10): 1812-1822, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34525864

RESUMO

North America's overdose crisis is an urgent public health issue that has resulted in thousands of deaths. As the crisis began to take hold across Canada in 2016, bereaved parents, mainly mothers, emerged as vocal advocates for drug policy reform and harm reduction, using their stories to challenge the stigma of drug-related death. In 2017, we launched a qualitative research partnership with leading family organizations in Canada, conducting interviews with 43 mothers whose children had died from substance use, to understand their experiences of drug policy advocacy. Our findings showed that participants' motivations for engaging in advocacy were rooted in their experiences of grief, and that advocacy led to feelings of empowerment and connection to others. Our research suggests that advocacy can be cathartic and associated with healing from grief, but that "going public" in sharing a family story of substance use death can also have a considerable personal cost.


Assuntos
Luto , Preparações Farmacêuticas , Criança , Feminino , Pesar , Humanos , Mães , Motivação , Políticas
6.
Z Kinder Jugendpsychiatr Psychother ; 49(6): 468-479, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-34269095

RESUMO

Developmental Speech and Language Disorders According to ICD-11 Abstract. In ICD-11, similar to ICD-10, speech and language disorders are classified as neurodevelopmental disorders, which are part of ICD-11 Chapter 6 (Mental, Behavioural and Neurodevelopmental Disorders). The ICD-10 criteria were not well accepted by many professionals in research and clinic who work with children with speech and language disorders. Especially linguists and speech and language therapists see ICD-10 as too crude and lacking specification of individual language problems. Medical professions in turn criticize the missing aspect of organically caused speech and language problems. This paper presents the classification of speech and language problems or disorders according to ICD-11 compared to ICD-10. One essential aspect lies in the differentiation between "primary" and "secondary" neurodevelopmental disorders. In addition, we compare and discuss other recent classification approaches, such as DSM-5, CATALISE-2, and the classification "Auditory Processing Disorder" by pediatric audiologists. We present a classification approach based on ICD-11, supplemented by an additional specification of the respective impaired speech or language area in the individual child and based on a thorough speech and language assessment. We thus hope to pave the path for an interdisciplinary classification of speech and language disorders according to ICD-11, our aim being to establish a common terminology that can be used by all professions. We expect this common terminology to improve clinical care and to allow for the integration and comparability of speech- and language-related research efforts.


Assuntos
Classificação Internacional de Doenças , Transtornos da Linguagem , Criança , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Transtornos da Linguagem/diagnóstico , Fala
7.
Cancers (Basel) ; 14(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35008289

RESUMO

BACKGROUND: Chemerin plasma concentration has been reported to be positively correlated with the risk of colorectal cancer. However, the potential regulation of CRC tumorigenesis and progression has not yet been investigated in an experimental setting. This study addresses this hypothesis by investigating proliferation, colony formation, and migration of CRC cell lines in vitro as well as in animal models. METHODS: In vitro, microscopic assays to study proliferation, as well as a scratch-wound assay for migration monitoring, were applied using the human CRC cell lines HCT116, HT29, and SW620 under the influence of the chemerin analog CG34. The animal study investigated HCT116-luc and HT29-luc subcutaneous tumor size and bioluminescence during treatment with CG34 versus control, followed by an ex-vivo analysis of vessel density and mitotic activity. RESULTS: While the proliferation of the three CRC cell lines in monolayers was not clearly stimulated by CG34, the chemerin analog promoted colony formation in three-dimensional aggregates. An effect on cell migration was not observed. In the treatment study, CG34 significantly stimulated both growth and bioluminescence signals of HCT116-luc and HT29-luc xenografts. CONCLUSIONS: The results of this study represent the first indication of a tumor growth-stimulating effect of chemerin signaling in CRC.

8.
Int J Drug Policy ; 91: 103011, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33127282

RESUMO

BACKGROUND: Globally, a tainted drug supply is claiming the lives of tens of thousands of people who use drugs and current measures are not quelling this crisis. Within this context, mothers who have lost a child to substance use have emerged as vocal advocates for drug policy changes. This paper explores mothers' experiences in drug policy advocacy to uncover how they are using their stories to drive policy change. METHODS: Critical qualitative and narrative methods informed individual interviews with 43 mothers who had lost a child to substance use from across three regions in Canada: British Columbia, Prairie Provinces, and Eastern Provinces. Multisite qualitative analysis (MSQA) provided a rigorous analytical method to identify how social context informed participants' advocacy efforts within and across geographies, together with a theoretical lens from Haraway to understand mothers' activism as situated knowledge. RESULTS: Mothers' drug policy advocacy was shaped by social context and norms, which influenced the types of advocacy targets pursued, within the constraints of the social and political ethos of each geographic region. Yet across regions, narratives of shared aims and experiences also emerged. Specifically, the notion that people of all backgrounds are dying and that losing a child to substance use can "happen to anyone" - though people who experience structural vulnerabilities are disproportionately impacted. Additionally, mothers' stories were identified as a particularly powerful tool for conveying emotional knowledge and prompting action that complements other forms of knowledge or evidence. CONCLUSION: To date, efforts to address the drug poisoning epidemic have done little to curb casualties. Mothers whose child's death is related to substance use are one group who are bringing their experiences to advocacy efforts aimed at generating new solutions, including calls for decriminalization and legal regulation of drugs. This and other lived experience perspectives represent a critical voice in decision-making and hold the potential to inform more responsive and impactful drug policy.


Assuntos
Mães , Preparações Farmacêuticas , Colúmbia Britânica , Criança , Feminino , Humanos , Política Pública , Pesquisa Qualitativa , Meio Social
9.
Int J Mol Sci ; 21(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233817

RESUMO

At least since March 2020, the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic and the multi-organ coronavirus disease 2019 (COVID-19) are keeping a firm grip on the world. Although most cases are mild, older patients and those with co-morbidities are at increased risk of developing a cytokine storm, characterized by a systemic inflammatory response leading to acute respiratory distress syndrome and organ failure. The present paper focuses on the small molecule MP1032, describes its mode of action, and gives rationale why it is a promising option for the prevention/treatment of the SARS-CoV-2-induced cytokine storm. MP1032 is a phase-pure anhydrous polymorph of 5-amino-2,3-dihydro-1,4-phthalazinedione sodium salt that exhibits good stability and bioavailability. The physiological action of MP1032 is based on a multi-target mechanism including localized, self-limiting reactive oxygen species (ROS) scavenging activities that were demonstrated in a model of lipopolysaccharide (LPS)-induced joint inflammation. Furthermore, its immune-regulatory and PARP-1-modulating properties, coupled with antiviral effects against SARS-CoV-2, have been demonstrated in various cell models. Preclinical efficacy was elucidated in LPS-induced endotoxemia, a model with heightened innate immune responses that shares many similarities to COVID-19. So far, during oral clinical development with three-month daily administrations, no serious adverse drug reactions occurred, highlighting the outstanding safety profile of MP1032.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Fatores Imunológicos/farmacologia , Inflamação/tratamento farmacológico , Luminol/análogos & derivados , Pneumonia Viral/tratamento farmacológico , Aminação , Animais , Antivirais/química , Betacoronavirus/imunologia , COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/imunologia , Citocinas/imunologia , Feminino , Humanos , Fatores Imunológicos/química , Inflamação/imunologia , Luminol/química , Luminol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pandemias , Pneumonia Viral/imunologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/imunologia , Espécies Reativas de Oxigênio/imunologia , SARS-CoV-2 , Células Vero
10.
Biologicals ; 52: 72-77, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29336864

RESUMO

Fibryga® is a new lyophilized fibrinogen concentrate for intravenous use for the treatment of congenital fibrinogen deficiency. fibryga® is produced from pooled human plasma and the final product is characterized by high purity, integrity, and pathogen safety. Functional activity of fibrinogen was demonstrated by cross-linking studies and thromboelastometry; integrity of the fibrinogen molecule was demonstrated by size exclusion chromatography and the detection of only trace amounts of activation markers in the final product. Pathogen safety of fibryga® was proved by downscaling studies for the two dedicated pathogen inactivation/removal steps, i.e. solvent detergent treatment and nanofiltration. Fibryga® is stable for at least three years when stored at room temperature. In conclusion, the performed studies demonstrated that fibryga® meets the requirements for a state-of-the-art fibrinogen concentrate, such as a satisfactory activity profile combined with a favorable pathogen safety profile and stability.


Assuntos
Desinfecção/métodos , Fibrinogênio/química , Fibrinogênio/isolamento & purificação , Estabilidade de Medicamentos , Humanos , Tromboelastografia/métodos
11.
Front Psychol ; 9: 2732, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30692953

RESUMO

In this paper, we investigate whether timing in monolingual acquisition interacts with age of onset and input effects in child bilingualism. Six different morpho-syntactic and semantic phenomena acquired early, late or very late are considered, with their timing in L1 acquisition varying between age 3 (subject-verb agreement) and after age 6 (case marking). Data from simultaneous bilingual children (2L1) whose mean age of onset to German was 3 months are compared with data from early second language learners of German (eL2) whose mean age of onset to German was 35 months as well as with data from monolingual children. To explore change over time, children were tested twice at the ages of 4;4 and 5;8 years. The main findings were that 2L1 children had an advantage over their eL2 peers in early acquired phenomena, which disappeared with time, whereas in late acquired phenomena 2L1 and eL2 children did not differ. Moreover, 2L1 children performed like monolingual children in early acquired phenomena but had a disadvantage in the late acquired phenomena with the amount of delay decreasing with time. We conclude that age of onset effects are modulated by effects of timing in monolingual acquisition. Contrary to expectation, input in terms of language dominance, measured as the dominant language used at home, did not affect simultaneous bilingual children's performance in any of the phenomena. We discuss the implications of our findings for the hypothesis that acquisition of late phenomena is determined by input alone and suggest an alternative concept: the learner's internal need for time to master a phenomenon, which is determined by its complexity and cross-linguistic robustness.

12.
Mol Imaging Biol ; 17(4): 450-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25622811

RESUMO

PURPOSE: Colorectal cancer (CRC) is one of the major causes of cancer-related deaths in industrialized countries. The identification of small polyps and neoplasms with non-polypoid morphology remains to be a serious challenge, as about a quarter of them are missed during routine colonoscopy. The aim of this study was to evaluate the application of an integrin αvß3 optical probe in near-infrared fluorescence (NIRF) confocal laser endomicroscopy (CLE) for tumour detection in a rodent model. PROCEDURES: In a novel orthotopic CRC mouse model, tumour growth was monitored by bioluminescence imaging and by colonoscopy employing a rigid white-light endoscope, tumour development was scored by total number and size of tumours. Furthermore, NIRF CLE was established using a fibre probe attached to a confocal laser scanner operating at 660 nm and an antagonistic small-molecule integrin αvß3 NIRF contrast agent. RESULTS: Three CRC cell lines of different histological origin were successfully implanted in nude mice, proving the power of this new orthotopic model. Whole body NIRF images of tumour-bearing mice showed specific high accumulation of the integrin αvß3 probe in regions of tumour growth, colocalizing with the bioluminescent signal. Molecular imaging by means of a CLE fibre probe allowed distinguishing normal mucosa structures from tumour tissue, as confirmed by quantitation of fluorescence intensities and histology. CONCLUSIONS: Targeting integrin αvß3 in a molecular imaging approach was shown to be effective for CRC detection. Use of molecular guidance in near-infrared CLE represents a promising route to improving detection rates.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Corantes Fluorescentes/química , Integrina alfaVbeta3/metabolismo , Microscopia Confocal/métodos , Imagem Molecular/métodos , Animais , Feminino , Corantes Fluorescentes/metabolismo , Células HCT116 , Xenoenxertos , Humanos , Integrina alfaVbeta3/química , Camundongos , Camundongos Nus , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
13.
Cancer Sci ; 103(2): 169-75, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22049925

RESUMO

Pancreatic cancer is characterized by oncogenic activation of K-Ras and inactivation of the cell cycle inhibitor p16(INK4a) . We previously demonstrated that reintroduction of p16(INK4a) reversed anoikis resistance and clonogenicity of human pancreatic cancer cells, properties commonly attributed to the transforming potential of oncogenic K-Ras. Therefore, we aimed to determine the role of Ras after p16(INK4a) re-expression. Here, we show that restitution of p16(INK4a) in pancreatic cancer cell lines elicits a profound suppression of K-Ras activity. A more detailed analysis in p16(INK4a) reconstituted Capan-1 cells indicated selective reduction of both K-Ras activity and protein stability. Re-expression of K-Ras in p16(INK4a) restituted Capan-1 cells reversed the anoikis-sensitive phenotype and increased colony formation, indicating that K-Ras suppression was required for p16(INK4a) -mediated reversion of the transformed phenotype. Inducible expression of p16(INK4a) in DanG cells confirmed inhibition of K-Ras activity as well as an increase in anoikis susceptibility. Thus, our results delineate a novel functional interaction with defined biological consequences for the two most frequent alterations observed in pancreatic cancer.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Proteína Oncogênica p21(ras)/metabolismo , Neoplasias Pancreáticas/metabolismo , Anoikis/genética , Ciclo Celular , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Neoplasias do Colo/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Genes Supressores de Tumor , Humanos , Proteína Oncogênica p21(ras)/biossíntese , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia
14.
FASEB J ; 25(10): 3325-35, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21685330

RESUMO

Lymphatic metastasis constitutes a critical route of disease dissemination, which limits the prognosis of patients with pancreatic ductal adenocarcinoma (PDAC). As lymphangiogenesis has been implicated in stimulation of lymphatic metastasis by vascular endothelial growth factor-C (VEGF-C) and VEGF-D, we studied the effect of the angioregulatory growth factor angiopoietin-2 (Ang-2) on PDAC progression. Ang-2 was found to be expressed in transformed cells of human PDAC specimens, with corresponding Tie-2 receptors present on blood and lymphatic endothelium. In vitro in PDAC cells, Ang-2 was subject to autocrine/paracrine TGF-ß stimulation (2-fold induction, P=0.0106) acting on the -61- to +476-bp element of the human Ang-2 promoter. In turn, Ang-2 regulated the expression of genes involved in cell motility and tumor suppression. Orthotopic PDAC xenografts with forced expression of Ang-2, but not Ang-1, displayed increased blood and lymphatic vessel density, and an enhanced rate of lymphatic metastasis (6.7- to 9.1-fold, P<0.01), which was prevented by sequestration of Ang-2 via coexpression of soluble Tie-2. Notably, elevated circulating Ang-2 in patients with PDAC correlated with the extent of lymphatic metastasis. Furthermore, median survival was reduced from 28.4 to 7.7 mo in patients with circulating Ang-2 ≥ 75th percentile (P=0.0005). These findings indicate that Ang-2 participates in the control of lymphatic metastasis, constitutes a noninvasive prognostic biomarker, and may provide an accessible therapeutic target in PDAC.


Assuntos
Adenocarcinoma/patologia , Angiopoietina-2/metabolismo , Metástase Linfática/fisiopatologia , Neoplasias Pancreáticas/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Idoso , Angiopoietina-2/sangue , Angiopoietina-2/genética , Animais , Biomarcadores , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Linfangiogênese/fisiologia , Masculino , Camundongos , Camundongos SCID , Neoplasias Experimentais , Neoplasias Pancreáticas/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor TIE-2/genética , Receptor TIE-2/metabolismo
15.
Clin Cancer Res ; 16(2): 420-9, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20068079

RESUMO

PURPOSE: Inhibition of angiogenesis represents a promising therapeutic strategy in neuroendocrine tumors. Angiopoietin-2 (Ang-2), a ligand of the endothelial tyrosine kinase Tie-2, is emerging as a key regulator of vascular remodeling during tumor angiogenesis. We therefore addressed the expression and biological significance of Ang-2 in human neuroendocrine tumors. EXPERIMENTAL DESIGN: Surgical specimens and serum from neuroendocrine tumor patients were used to determine Ang-2 expression by in situ hybridization or ELISA (circulating Ang-2). Ang-2 biological effects were evaluated following stable transfection into BON human pancreatic neuroendocrine tumor cells. BON clones were grown as orthotopic xenografts in nude mice to determine tumor growth and abdominal metastatic spread. Further analyses included microvessel density, lymphatic vessel density, and nodal invasion. RESULTS: Specimens from pancreatic neuroendocrine tumors and nontransformed pancreatic tissue revealed uniform expression of Ang-2 mRNA in endothelial cells. In contrast, epithelial expression of Ang-2 mRNA occurred exclusively in neuroendocrine tumors. Overexpression of Ang-2 in BON orthotopic xenografts did not affect primary tumor growth, although successful Ang-2 induction was confirmed from elevated serum levels. However, increased microvessel density and enhanced lymphatic metastasis were evident in Ang-2-expressing tumors, indicating a functional role of Ang-2 in experimental neuroendocrine tumors. Consistent with this notion, circulating Ang-2 was significantly elevated in neuroendocrine tumor patients compared with healthy controls. Circulating Ang-2 furthermore correlated with metastatic versus localized disease. The highest Ang-2 concentrations occurred in patients with liver metastasis, and concentrations >or=75th percentile predicted shorter survival (P = 0.0003). CONCLUSION: Induction of Ang-2 in neuroendocrine tumors represents a clinically relevant pathomechanism of disease progression and constitutes an adverse prognostic marker.


Assuntos
Angiopoietina-2/fisiologia , Neoplasias Gastrointestinais/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Angiopoietina-2/sangue , Angiopoietina-2/genética , Animais , Estudos de Casos e Controles , Progressão da Doença , Feminino , Neoplasias Gastrointestinais/sangue , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Camundongos , Pessoa de Meia-Idade , Transplante de Neoplasias , Neovascularização Patológica/genética , Tumores Neuroendócrinos/sangue , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/genética , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Prognóstico , Transplante Heterólogo , Células Tumorais Cultivadas , Adulto Jovem
16.
Cancer Res ; 68(23): 9788-98, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19047158

RESUMO

We have previously described a small interfering RNA (siRNA) delivery system (AtuPLEX) for RNA interference (RNAi) in the vasculature of mice. Here we report preclinical data for Atu027, a siRNA-lipoplex directed against protein kinase N3 (PKN3), currently under development for the treatment of advanced solid cancer. In vitro studies revealed that Atu027-mediated inhibition of PKN3 function in primary endothelial cells impaired tube formation on extracellular matrix and cell migration, but is not essential for proliferation. Systemic administration of Atu027 by repeated bolus injections or infusions in mice, rats, and nonhuman primates results in specific, RNAi-mediated silencing of PKN3 expression. We show the efficacy of Atu027 in orthotopic mouse models for prostate and pancreatic cancers with significant inhibition of tumor growth and lymph node metastasis formation. The tumor vasculature of Atu027-treated animals showed a specific reduction in lymph vessel density but no significant changes in microvascular density.


Assuntos
Neoplasias Pancreáticas/terapia , Neoplasias da Próstata/terapia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Animais , Processos de Crescimento Celular/fisiologia , Progressão da Doença , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Células HeLa , Humanos , Lipossomos/administração & dosagem , Metástase Linfática , Macaca fascicularis , Masculino , Camundongos , Camundongos SCID , Neovascularização Patológica/enzimologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Interferência de RNA , Ratos , Transfecção/métodos
17.
Clin Cancer Res ; 14(15): 4951-60, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18676770

RESUMO

PURPOSE: Effective control of pancreatic cancer has been hampered primarily by the lack of tumor specificity of current treatment modalities. The highly specific antibody-mediated delivery of therapeutic agents to the tumor microenvironment might overcome this problem. We therefore investigated the therapeutic efficacy of the targeted immunocytokine L19-Interleukin-2 (L19-IL2), consisting of the human single-chain Fv antibody L19, which is highly specific for the extradomain B (ED-B) of fibronectin, and the human cytokine IL-2, in pancreatic cancer. EXPERIMENTAL DESIGN: Therapeutic effects of L19-IL-2, IL-2, and gemcitabine on tumor growth and metastasis were evaluated in orthotopic mouse models for pancreatic cancer. Immunohistochemistry was done to define ED-B expression, tumor necrosis, apoptosis, proliferation, and invasion of macrophages and natural killer (NK) cells. NK cells were depleted by i.v. injection of an anti-asialo-GM-1 antibody. RESULTS: ED-B is selectively expressed in human pancreatic cancer and in primary tumors and metastases of the mouse models. L19-IL-2 therapy was clearly superior to untargeted IL-2 or gemcitabine and inhibited tumor growth and metastasis with remarkable long-term tumor control. Therapeutic effects were associated with the induction of extensive tumor necrosis and inhibition of tumor cell proliferation. Immunohistochemistry revealed an increase of macrophages and NK cells in the tumor tissue, suggesting immune-mediated mechanisms. The functional relevance of NK cells for the therapeutic effect of the targeted immunocytokine L19-IL-2 was confirmed by NK cell depletion, which completely abolished its antitumor efficacy. CONCLUSIONS: These preclinical results strongly encourage the initiation of clinical studies using L19-IL-2 in pancreatic cancer.


Assuntos
Citocinas/metabolismo , Interleucina-2/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Ribossômicas/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Feminino , Humanos , Células Matadoras Naturais/citologia , Camundongos , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica
19.
Neuroendocrinology ; 87(4): 233-42, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18025811

RESUMO

Somatostatin receptor (SSTR) scintigraphy is currently used as one standard imaging modality in neuroendocrine tumors (NETs). However, future optimization of NET imaging may be achieved with positron emission tomography based methods utilizing more sensitive and specific tracers in combination with computed tomography or magnetic resonance imaging. Here we established an orthotopic mouse model that reflects relevant aspects of human pancreatic NETs such as SSTR expression, dense vascularization and metastatic disease. This model was then utilized to test the feasibility of combined magnetic resonance imaging and animal positron emission tomography. Orthotopic implantation of amphicrine, SSTR-positive pancreatic AR42J cells resulted in rapidly growing tumors, with concomitant metastatic spread into abdominal lymph nodes and peritoneal cavity. Primary tumors as well as their metastases expressed the neuroendocrine markers chromogranin A and synaptophysin. For imaging experiments, the SSTR ligands (68)Ga-DOTATOC or (68)Ga-DOTANOC were injected intravenously, and animals were subsequently examined in an animal positron emission tomography scanner and a clinical 3T (tesla) magnetic resonance imager. All animals showed radionuclide accumulation in the primary tumor. Definite anatomical correlation was achieved using digital image fusion of the positron emission tomography and magnetic resonance imaging data. (68)Ga-DOTANOC strongly accumulated in the tumor tissue (mean 6.6-fold vs. control tissues) when compared to (68)Ga-DOTATOC, which showed a higher renal clearance. In good agreement with the biodistribution data, the kidney-to-tumor ratio was higher for (68)Ga-DOTATOC (2.43-fold vs. 1.75-fold). Consequently, (68)Ga-DOTANOC achieved better signal enhancement in the primary tumor and allowed for detection of metastatic lesions. In summary, we established a novel orthotopic pancreatic SSTR-positive tumor model and used this model to provide proof of principle for the diagnostic combination of SSTR-based molecular imaging and magnetic resonance imaging. Specifically, the animal model allowed the comparative evaluation of (68)Ga-DOTANOC and (68)Ga-DOTATOC, with (68)Ga-DOTANOC providing better tumor-specific accumulation and renal activity. We conclude that this animal model will be of innovative value for further investigation in the imaging of NETs.


Assuntos
Modelos Animais de Doenças , Imageamento por Ressonância Magnética/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Tomografia por Emissão de Pósitrons/métodos , Receptores de Somatostatina/metabolismo , Transplante Heterólogo , Animais , Feminino , Camundongos , Camundongos Nus , Metástase Neoplásica , Neoplasias Pancreáticas/metabolismo , Ratos , Células Tumorais Cultivadas
20.
Am J Gastroenterol ; 102(11): 2471-81, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17581268

RESUMO

OBJECTIVES: Liver cirrhosis is characterized by remodeling leading to nodules that are difficult to discern from hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) serum levels are used for the screening for HCC, with limited success. We evaluated angiopoietin-2 as a serum marker in patients with cirrhosis and with HCC. METHODS: In a retrospective study, we measured angiopoietin-2 serum levels in 131 patients with HCC, 180 patients with cirrhosis, and 40 healthy controls. We also determined AFP serum levels in patients with HCC and compared the test characteristics of both serum markers. The expression patterns of angiopoietin-2 were determined by in situ hybridization in healthy and cirrhotic livers as well as in HCC. RESULTS: Angiopoietin-2 serum levels were elevated in patients with liver cirrhosis (P < 0.0001) compared with healthy controls. Levels were further elevated in patients with HCC compared with healthy controls (P < 0.0001) and cirrhotic patients (P < 0.0001). The combination with AFP measurements led to improved discrimination between HCC and cirrhosis. Angiopoietin-2 message was present in tumor cells of HCCs but was absent from hepatocytes of cirrhotic and healthy livers. In cirrhosis, message was detected within the strands of fibrous tissue. CONCLUSIONS: Serum angiopoietin-2 levels are elevated in patients with cirrhosis, implicating a possible role of the angiopoietin-Tie-2 system for neoangiogenesis in cirrhosis. Serum levels are further elevated in patients with HCC, suggesting the potential use of angiopoietin-2 as a marker for the detection of cirrhosis and HCC.


Assuntos
Angiopoietina-2/sangue , Carcinoma Hepatocelular/sangue , Cirrose Hepática/sangue , Neoplasias Hepáticas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Estudos de Casos e Controles , Feminino , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/sangue , Curva ROC , Estudos Retrospectivos , Estatísticas não Paramétricas
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