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1.
J Endocrinol Invest ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900374

RESUMEN

BACKGROUND: Thyroid cancer is the most common endocrine malignancy. Current therapies are successful, however some patients progress to therapeutically refractive disease. The immunotherapeutic potential of the CXCL8-chemokine/CXCR2-chemokine-receptor system is currently being explored in numerous human cancers. This study aimed to evaluate if the targeting of CXCR2 by its selective antagonist, AZD5069, could modulate CXCL8-mediated pro-tumorigenic effects in thyroid-cancer (TC) cells in vitro. METHODS: Normal human primary thyroid cells (NHT) and TC cell lines TPC-1 (RET/PTC), BCPAP, 8505C and 8305C (BRAFV600e) were treated with AZD5069 (100 pM-10 µM) over a time-course. Viability and proliferation were assessed by WST-1 and crystal violet assays. CXCL8 and CXCR2 mRNA were evaluated by RT-PCR. CXCL8-protein concentrations were measured in cell culture supernatants by ELISA. CXCR2 on cell surface was evaluated by flow-cytometry. Cell-migration was assessed by trans-well-migration chamber-system. RESULTS: AZD5069 exerted negligible effects on cell proliferation or viability. AZD5069 significantly reduced CXCR2, (but not CXCL8) mRNAs in all cell types. CXCR2 was reduced on the membrane of some TC cell lines. A significant reduction of the CXCL8 secretion was found in TPC-1 cells (basal-secretion) and NHT (TNFα-induced secretion). AZD5069 significantly reduced basal and CXCL8-induced migration in NHT and different TC cells. CONCLUSIONS: Our findings confirm the involvement of the CXCL8/CXCR2-axis in promoting pro-tumorigenic effects in TC cells, further demonstrating its immunotherapeutic significance in human cancer.

2.
Bioscience ; 72(4): 372-386, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35370478

RESUMEN

Ecosystem management and governance of cross-scale dependent systems require integrating knowledge about ecological connectivity in its multiple forms and scales. Although scientists, managers, and policymakers are increasingly recognizing the importance of connectivity, governmental organizations may not be currently equipped to manage ecosystems with strong cross-boundary dependencies. Managing the different aspects of connectivity requires building social connectivity to increase the flow of information, as well as the capacity to coordinate planning, funding, and actions among both formal and informal governance bodies. We use estuaries in particular the San Francisco Estuary, in California, in the United States, as examples of cross-scale dependent systems affected by many intertwined aspects of connectivity. We describe the different types of estuarine connectivity observed in both natural and human-affected states and discuss the human dimensions of restoring beneficial physical and ecological processes. Finally, we provide recommendations for policy, practice, and research on how to restore functional connectivity to estuaries.

3.
J Fish Biol ; 96(2): 527-532, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31583703

RESUMEN

Temperature and sea level are predicted to rise with climate change, bringing an urgency to evaluating future viability of native fish. Lamprey are confronted with widespread habitat degradation, migratory barriers, and episodes of environmental change projected to be commonplace in the future. In California, range contraction likely shifted lamprey rearing downstream, but the extent and physiological constraints that restrict estuarine rearing are unclear. We used a single-season occupancy model to describe juvenile lamprey estuarine distribution and found occupancy was regionally variable and constrained by temperature. Habitat and hydrology providing thermal refugia may be critical for future persistence.


Asunto(s)
Distribución Animal , Lampreas/fisiología , Refugio de Fauna , Temperatura , Animales , California , Ecosistema , Estaciones del Año
4.
Environ Sci Technol ; 53(3): 1422-1431, 2019 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-30672293

RESUMEN

Information on ocean scale drivers of methylmercury levels and variability in tuna is scarce, yet crucial in the context of anthropogenic mercury (Hg) inputs and potential threats to human health. Here we assess Hg concentrations in three commercial tuna species (bigeye, yellowfin, and albacore, n = 1000) from the Western and Central Pacific Ocean (WCPO). Models were developed to map regional Hg variance and understand the main drivers. Mercury concentrations are enriched in southern latitudes (10°S-20°S) relative to the equator (0°-10°S) for each species, with bigeye exhibiting the strongest spatial gradients. Fish size is the primary factor explaining Hg variance but physical oceanography also contributes, with higher Hg concentrations in regions exhibiting deeper thermoclines. Tuna trophic position and oceanic primary productivity were of weaker importance. Predictive models perform well in the Central Equatorial Pacific and Hawaii, but underestimate Hg concentrations in the Eastern Pacific. A literature review from the global ocean indicates that size tends to govern tuna Hg concentrations, however regional information on vertical habitats, methylmercury production, and/or Hg inputs are needed to understand Hg distribution at a broader scale. Finally, this study establishes a geographical context of Hg levels to weigh the risks and benefits of tuna consumption in the WCPO.


Asunto(s)
Mercurio , Atún , Animales , Hawaii , Humanos , Océanos y Mares , Océano Pacífico
5.
Int J Mol Sci ; 20(11)2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31195751

RESUMEN

Endocrine therapies targeting oestrogen signalling have significantly improved breast cancer management. However, their efficacy is limited by intrinsic and acquired resistance to treatment, which remains a major challenge for oestrogen receptor α (ERα)-positive tumours. Though many studies using in vitro models of endocrine resistance have identified putative actors of resistance, no consensus has been reached. We demonstrated previously that oestrogen non-genomic signalling, characterized by the formation of the ERα/Src/PI3K complex, is activated in aggressive breast cancers (BC). We wondered herein whether the activation of this pathway is also involved in resistance to endocrine therapies. We studied the interactions between ERα and Src or PI3K by proximity ligation assay (PLA) in in-vitro and in-vivo endocrine therapy-resistant breast cancer models. We reveal an increase in ERα/Src and ERα/PI3K interactions in patient-derived xenografts (PDXs) with acquired resistance to tamoxifen, as well as in tamoxifen-resistant MCF-7 cells compared to parental counterparts. Moreover, no interactions were observed in breast cancer cells resistant to other endocrine therapies. Finally, the use of a peptide inhibiting the ERα-Src interaction partially restored tamoxifen sensitivity in resistant cells, suggesting that such components could constitute promising targets to circumvent resistance to tamoxifen in BC.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Resistencia a Antineoplásicos/efectos de los fármacos , Estrógenos/farmacología , Transducción de Señal , Tamoxifeno/farmacología , Animales , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Células MCF-7 , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/metabolismo , Familia-src Quinasas/metabolismo
6.
Cogn Process ; 20(3): 291-298, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30569268

RESUMEN

The concept of "presence" describes the quality of subjective experience in immersive virtual reality (IVR). Presence refers to a specific state of consciousness: we behave and feel as if we actually were in the virtual world even though we know there is nothing there. In their handbook of Virtual Reality, Burdea and Coiffet (Virtual reality technology, Wiley, New York, 2003) suggested that the experience of presence in IVR would emerge from the combination of three Is: Immersion or capacity to isolate from the external world, Interaction or capacity to naturally exploring the virtual environment, and Imagination or individual aptitudes with mental imagery. So far, several studies have investigated the technological and psychological factors affecting the degree of immersion and interaction. However, no study has explored the relationship between perceived presence and mental imagery. Here we aim at filling this gap through a correlational study comparing self-reports about sense of presence and mental imagery abilities. After experiencing two IVR scenarios (an art gallery and a living room), 142 male and female users were administered with questionnaires assessing the degree of presence (Igroup Presence Questionnaire), the degree of vividness (Vividness of Visual Imagery Questionnaire) and control (Test of Visual Imagery Control) of subjective mental images. Results showed a clear positive correlation between presence and vividness: the higher the vividness of mental images the stronger the reported sense of presence felt in IVR scenarios. Instead, the capacity to control mental imagery showed a weaker association with presence. We may conclude that individual differences in the degree of perceived presence and mental imagery ability are associated.


Asunto(s)
Imágenes en Psicoterapia , Individualidad , Realidad Virtual , Adulto , Femenino , Humanos , Imaginación , Masculino , Encuestas y Cuestionarios
7.
Nanotechnology ; 29(23): 235301, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29547134

RESUMEN

The last decade has come across an increasing demand for theranostic biocompatible nanodevices possessing the double ability of diagnosis and therapy. In this work, we report the design, synthesis and step-by-step characterization of rationally coated gold nanostars (GNSs) for the SERS imaging and photothermal therapy of HeLa cancer cells. The nanodevices were realized by synthesizing GNSs with a seed growth approach, coating them with a controlled mixture of thiols composed of a Raman reporter and a polyethylene glycol with a terminal amino group, and then reacting these amino groups with folic acid (FA), in order to impart selectivity towards cancer cells which overexpress folate receptors on their membranes. After a complete characterization, we demonstrate that these FA-functionalized GNSs (FA-GNSs) are able to bind selectively to the membranes of HeLa cells, acting as SERS tags and allowing SERS imaging. Moreover, we demonstrate that once bound to HeLa cell membranes, FA-GNSs exhibit photothermal effect which can be exploited to kill the same cells in vitro using laser irradiation in the NIR at a very low and safe irradiance. We thus demonstrate that the FA-GNSs designed following the described approach are an efficient prototype of theranostic nanodevices.

8.
J Pathol ; 242(1): 73-89, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28207159

RESUMEN

Bone metastasis affects >70% of patients with advanced breast cancer. However, the molecular mechanisms underlying this process remain unclear. On the basis of analysis of clinical datasets, and in vitro and in vivo experiments, we report that the ZNF217 oncogene is a crucial mediator and indicator of bone metastasis. Patients with high ZNF217 mRNA expression levels in primary breast tumours had a higher risk of developing bone metastases. MDA-MB-231 breast cancer cells stably transfected with ZNF217 (MDA-MB-231-ZNF217) showed the dysregulated expression of a set of genes with bone-homing and metastasis characteristics, which overlapped with two previously described 'osteolytic bone metastasis' gene signatures, while also highlighting the bone morphogenetic protein (BMP) pathway. The latter was activated in MDA-MB-231-ZNF217 cells, and its silencing by inhibitors (Noggin and LDN-193189) was sufficient to rescue ZNF217-dependent cell migration, invasion or chemotaxis towards the bone environment. Finally, by using non-invasive multimodal in vivo imaging, we found that ZNF217 increases the metastatic growth rate in the bone and accelerates the development of severe osteolytic lesions. Altogether, the findings of this study highlight ZNF217 as an indicator of the emergence of breast cancer bone metastasis; future therapies targeting ZNF217 and/or the BMP signalling pathway may be beneficial by preventing the development of bone metastases. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Neoplasias Óseas/genética , Neoplasias Óseas/secundario , Neoplasias de la Mama/genética , Transactivadores/genética , Animales , Proteínas Morfogenéticas Óseas/metabolismo , Neoplasias Óseas/metabolismo , Remodelación Ósea/genética , Neoplasias de la Mama/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Xenoinjertos , Humanos , Estimación de Kaplan-Meier , Ratones Desnudos , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Trasplante de Neoplasias , ARN Mensajero/genética , ARN Neoplásico/genética , Transducción de Señal/genética , Transactivadores/biosíntesis , Células Tumorales Cultivadas
9.
BMC Pregnancy Childbirth ; 17(1): 320, 2017 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-28946843

RESUMEN

BACKGROUND: Intermittent Auscultation (IA) is the recommended method of fetal surveillance for healthy women in labour. However, the majority of women receive continuous electronic monitoring. We used the Theoretical Domains Framework (TDF) to explore the views of Birthing Unit nurses about using IA as their primary method of fetal surveillance for healthy women in labour. METHODS: Using a semi-structured interview guide, we interviewed a convenience sample of birthing unit nurses throughout Ontario, Canada to elicit their views about fetal surveillance. Interviews were recorded and transcribed verbatim. Transcripts were content analysed using the TDF and themes were framed as belief statements. Domains potentially key to changing fetal surveillance behaviour and informing intervention design were identified by noting the frequencies of beliefs, content, and their reported influence on the use of IA. RESULTS: We interviewed 12 birthing unit nurses. Seven of the 12 TDF domains were perceived to be key to changing birthing unit nurses' behaviour The nurses reported that competing tasks, time constraints and the necessity to multitask often limit their ability to perform IA (domains Beliefs about capabilities; Environmental context and resources). Some nurses noted the decision to use IA was something that they consciously thought about with every patient while others stated it their default decision as long as there were no risk factors (Memory, attention and decision processes, Nature of behaviour). They identified positive consequences (e.g. avoid unnecessary interventions, mother-centered care) and negative consequences of using IA (e.g. legal concerns) and reported that the negative consequences can often outweigh positive consequences (Beliefs about consequences). Some reported that hospital policies and varying support from care teams inhibited their use of IA (Social influences), and that support from the entire team and hospital management would likely increase their use (Social influences; Behavioural regulation). CONCLUSION: We identified potential influences on birthing unit nurses' use of IA as their primary method of fetal surveillance. These beliefs suggest potential targets for behaviour change interventions to promote IA use.


Asunto(s)
Auscultación , Monitoreo Fetal , Enfermería Obstétrica , Pautas de la Práctica en Enfermería , Auscultación/métodos , Salas de Parto , Femenino , Humanos , Entrevistas como Asunto , Trabajo de Parto/fisiología , Modelos Teóricos , Política Organizacional , Grupo de Atención al Paciente , Embarazo , Factores de Riesgo , Factores de Tiempo , Carga de Trabajo
11.
Nanotechnology ; 27(26): 265302, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27199302

RESUMEN

Surface modification of noble metal nanoparticles with mixed molecular monolayers is one of the most powerful tools in nanotechnology, and is used to impart and tune new complex surface properties. In imaging techniques based on surface enhanced Raman spectroscopy (SERS), precise and controllable surface modifications are needed to carefully design reproducible, robust and adjustable SERS nanoprobes. We report here the attainment of SERS labels based on gold nanostars (GNSs) coated with a mixed monolayer composed of a poly ethylene glycol (PEG) thiol (neutral or negatively charged) that ensure stability in biological environments, and of a signalling unit 7-Mercapto-4-methylcoumarin as a Raman reporter molecule. The composition of the coating mixture is precisely controlled using an original method, allowing the modulation of the SERS intensity and ensuring overall nanoprobe stability. The further addition of a positively charged layer of poly (allylamine hydrocloride) on the surface of negatively charged SERS labels does not change the SERS response, but it promotes the penetration of GNSs in SH-SY5Y neuroblastoma cells. As an example of an application of such an approach, we demonstrate here the internalization of these new labels by means of visualization of cell morphology obtained with SERS mapping.


Asunto(s)
Oro/química , Nanopartículas del Metal , Nanotecnología , Espectrometría Raman , Propiedades de Superficie
12.
Proc Natl Acad Sci U S A ; 110(48): 19525-30, 2013 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-24218572

RESUMEN

Cyclin-dependent kinases (CDKs) regulate a variety of fundamental cellular processes. CDK10 stands out as one of the last orphan CDKs for which no activating cyclin has been identified and no kinase activity revealed. Previous work has shown that CDK10 silencing increases ETS2 (v-ets erythroblastosis virus E26 oncogene homolog 2)-driven activation of the MAPK pathway, which confers tamoxifen resistance to breast cancer cells. The precise mechanisms by which CDK10 modulates ETS2 activity, and more generally the functions of CDK10, remain elusive. Here we demonstrate that CDK10 is a cyclin-dependent kinase by identifying cyclin M as an activating cyclin. Cyclin M, an orphan cyclin, is the product of FAM58A, whose mutations cause STAR syndrome, a human developmental anomaly whose features include toe syndactyly, telecanthus, and anogenital and renal malformations. We show that STAR syndrome-associated cyclin M mutants are unable to interact with CDK10. Cyclin M silencing phenocopies CDK10 silencing in increasing c-Raf and in conferring tamoxifen resistance to breast cancer cells. CDK10/cyclin M phosphorylates ETS2 in vitro, and in cells it positively controls ETS2 degradation by the proteasome. ETS2 protein levels are increased in cells derived from a STAR patient, and this increase is attributable to decreased cyclin M levels. Altogether, our results reveal an additional regulatory mechanism for ETS2, which plays key roles in cancer and development. They also shed light on the molecular mechanisms underlying STAR syndrome.


Asunto(s)
Canal Anal/anomalías , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Hipertelorismo/genética , Riñón/anomalías , Proteolisis , Proteína Proto-Oncogénica c-ets-2/metabolismo , Sindactilia/genética , Dedos del Pie/anomalías , Anomalías Urogenitales/genética , Canal Anal/metabolismo , Western Blotting , Línea Celular Tumoral , Quinasas Ciclina-Dependientes/deficiencia , Ciclinas/genética , Células HEK293 , Humanos , Hipertelorismo/metabolismo , Inmunoprecipitación , Riñón/metabolismo , Células MCF-7 , Complejo de la Endopetidasa Proteasomal/metabolismo , Sindactilia/metabolismo , Técnicas del Sistema de Dos Híbridos , Anomalías Urogenitales/metabolismo
13.
Breast Cancer Res ; 17: 13, 2015 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-25633049

RESUMEN

INTRODUCTION: Increasing evidence indicates that microRNAs (miRNAs) are important players in oncogenesis. Considering the widespread use of aromatase inhibitors (AIs) in endocrine therapy as a first-line treatment for postmenopausal estrogen receptor α-positive breast cancer patients, identifying deregulated expression levels of miRNAs in association with AI resistance is of utmost importance. METHODS: To gain further insight into the molecular mechanisms underlying the AI resistance, we performed miRNA microarray experiments using a new model of acquired resistance to letrozole (Res-Let cells), obtained by long-term exposure of aromatase-overexpressing MCF-7 cells (MCF-7aro cells) to letrozole, and a model of acquired anastrozole resistance (Res-Ana cells). Three miRNAs (miR-125b, miR-205 and miR-424) similarly deregulated in both AI-resistant cell lines were then investigated in terms of their functional role in AI resistance development and breast cancer cell aggressiveness and their clinical relevance using a cohort of 65 primary breast tumor samples. RESULTS: We identified the deregulated expression of 33 miRNAs in Res-Let cells and of 18 miRNAs in Res-Ana cells compared with the sensitive MCF-7aro cell line. The top-ranked Kyoto Encyclopedia of Genes and Genomes pathways delineated by both miRNA signatures converged on the AKT/mTOR pathway, which was found to be constitutively activated in both AI-resistant cell lines. We report for the first time, to our knowledge, that ectopic overexpression of either miR-125b or miR-205, or the silencing of miR-424 expression, in the sensitive MCF-7aro cell line was sufficient to confer resistance to letrozole and anastrozole, to target and activate the AKT/mTOR pathway and to increase the formation capacity of stem-like and tumor-initiating cells possessing self-renewing properties. Increasing miR-125b expression levels was also sufficient to confer estrogen-independent growth properties to the sensitive MCF-7aro cell line. We also found that elevated miR-125b expression levels were a novel marker for poor prognosis in breast cancer and that targeting miR-125b in Res-Let cells overcame letrozole resistance. CONCLUSION: This study highlights that acquisition of specific deregulated miRNAs is a newly discovered alternative mechanism developed by AI-resistant breast cancer cells to achieve constitutive activation of the AKT/mTOR pathway and to develop AI resistance. It also highlights that miR-125b is a new biomarker of poor prognosis and a candidate therapeutic target in AI-resistant breast cancers.


Asunto(s)
Inhibidores de la Aromatasa/farmacología , Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Antineoplásicos/farmacología , Antineoplásicos Hormonales , Inhibidores de la Aromatasa/uso terapéutico , Biomarcadores de Tumor , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Análisis por Conglomerados , Estudios de Cohortes , Resistencia a Antineoplásicos/genética , Femenino , Perfilación de la Expresión Génica , Humanos , Letrozol , Células MCF-7 , Recurrencia Local de Neoplasia , Nitrilos/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Pronóstico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Estrógenos , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Triazoles/farmacología , Células Tumorales Cultivadas , Regulación hacia Arriba
14.
Value Health ; 18(5): 587-96, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26297086

RESUMEN

BACKGROUND: Compared with new technologies, the redesign of care processes is generally considered less attractive to improve patient outcomes. Nevertheless, it might result in better patient outcomes, without further increasing costs. Because early initiation of treatment is of vital importance for patients with head and neck cancer (HNC), these care processes were redesigned. OBJECTIVES: This study aimed to assess patient outcomes and cost-effectiveness of this redesign. METHODS: An economic (Markov) model was constructed to evaluate the biopsy process of suspicious lesion under local instead of general anesthesia, and combining computed tomography and positron emission tomography for diagnostics and radiotherapy planning. Patients treated for HNC were included in the model stratified by disease location (larynx, oropharynx, hypopharynx, and oral cavity) and stage (I-II and III-IV). Probabilistic sensitivity analyses were performed. RESULTS: Waiting time before treatment start reduced from 5 to 22 days for the included patient groups, resulting in 0.13 to 0.66 additional quality-adjusted life-years. The new workflow was cost-effective for all the included patient groups, using a ceiling ratio of €80,000 or €20,000. For patients treated for tumors located at the larynx and oral cavity, the new workflow resulted in additional quality-adjusted life-years, and costs decreased compared with the regular workflow. The health care payer benefited €14.1 million and €91.5 million, respectively, when individual net monetary benefits were extrapolated to an organizational level and a national level. CONCLUSIONS: The redesigned care process reduced the waiting time for the treatment of patients with HNC and proved cost-effective. Because care improved, implementation on a wider scale should be considered.


Asunto(s)
Técnicas y Procedimientos Diagnósticos/economía , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/economía , Costos de la Atención en Salud , Evaluación de Procesos, Atención de Salud/economía , Tiempo de Tratamiento/economía , Listas de Espera , Anestesia General/economía , Anestesia Local/economía , Biopsia/economía , Análisis Costo-Beneficio , Neoplasias de Cabeza y Cuello/terapia , Humanos , Cadenas de Markov , Modelos Económicos , Imagen Multimodal/economía , Estadificación de Neoplasias , Tomografía de Emisión de Positrones/economía , Valor Predictivo de las Pruebas , Evaluación de Programas y Proyectos de Salud , Años de Vida Ajustados por Calidad de Vida , Factores de Tiempo , Tomografía Computarizada por Rayos X/economía , Resultado del Tratamiento , Flujo de Trabajo
15.
Environ Sci Technol ; 49(1): 223-32, 2015 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-25437177

RESUMEN

Our understanding of the biogeochemical cycling of monomethylmercury (MMHg) in the Arctic is incomplete because atmospheric sources and sinks of MMHg are still unclear. We sampled air in the Canadian Arctic marine boundary layer to quantify, for the first time, atmospheric concentrations of methylated Hg species (both MMHg and dimethylmercury (DMHg)), and, estimate the importance of atmospheric deposition as a source of MMHg to Arctic land- and sea-scapes. Overall atmospheric MMHg and DMHg concentrations (mean ± SD) were 2.9 ± 3.6 and 3.8 ± 3.1 (n = 37) pg m(-3), respectively. Concentrations of methylated Hg species in the marine boundary layer varied significantly among our sites, with a predominance of MMHg over Hudson Bay (HB), and DMHg over Canadian Arctic Archipelago (CAA) waters. We concluded that DMHg is of marine origin and that primary production rate and sea-ice cover are major drivers of its concentration in the Canadian Arctic marine boundary layer. Summer wet deposition rates of atmospheric MMHg, likely to be the product of DMHg degradation in the atmosphere, were estimated at 188 ± 117.5 ng m(-2) and 37 ± 21.7 ng m(-2) for HB and CAA, respectively, sustaining MMHg concentrations available for biomagnification in the pelagic food web.


Asunto(s)
Contaminantes Atmosféricos/análisis , Cubierta de Hielo/química , Compuestos de Metilmercurio/análisis , Regiones Árticas , Atmósfera , Canadá , Cadena Alimentaria , Mercurio/análisis , Estaciones del Año , Agua de Mar , Contaminantes Químicos del Agua/análisis
16.
Int J Health Care Qual Assur ; 28(1): 64-74, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26308403

RESUMEN

PURPOSE: For change programs to succeed, it is vital to have a detailed understanding of employees' views regarding the program, especially when the proposed changes are potentially contested. Gaining insight into employee perceptions helps managers to decide how to proceed. The authors conducted two workshops in a radiotherapy institute to assess the benefits and drawbacks, as well as their underlying causes, of a proposed Lean change program. Managers' views on the workshops' usefulness were charted. The paper aims to discuss these issues. DESIGN/METHODOLOGY/APPROACH: Two workshops were organized in which employees predicted positive and negative effects of a Lean program. The workshops combined a structured brainstorm (KJ-technique) and an evaluation of the expected effects. Eight top managers judged the workshops' value on supporting decision making. FINDINGS: In total, 15 employees participated in the workshops. Participants from workshop 2 reported more expected effects (27 effects; 18 positive) than from workshop 1 (14 effects; six positive). However, when effects were categorized, similar results were shown. Three from eight managers scored the results relevant for decision making and four neutral. Seven managers recommended future use of the instrument. Increased employee involvement and bottom-up thinking combined with relatively low costs were appreciated most. PRACTICAL IMPLICATIONS: The workshop could serve as a simple instrument to improve decision making and enhance successful implementation of change programs, as it was expected to enhance employees' involvement and was relatively easy to conduct and cheap. ORIGINALITY/VALUE: The workshop increased insight into employee views, facilitating adaptive actions by healthcare organization managers.


Asunto(s)
Eficiencia Organizacional , Liderazgo , Mejoramiento de la Calidad/organización & administración , Comunicación , Toma de Decisiones , Administradores de Instituciones de Salud , Personal de Salud , Humanos , Satisfacción en el Trabajo , Países Bajos , Cultura Organizacional , Seguridad del Paciente , Solución de Problemas
17.
Cancers (Basel) ; 16(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38730605

RESUMEN

Rhabdomyosarcoma is a pediatric cancer associated with aggressiveness and a tendency to develop metastases. Fusion-negative rhabdomyosarcoma (FN-RMS) is the most commonly occurring subtype of RMS, where metastatic disease can hinder treatment success and decrease survival rates. RMS-derived exosomes were previously demonstrated to be enriched with miRNAs, including miR-1246, possibly contributing to disease aggressiveness. We aimed to decipher the functional impact of exosomal miR-1246 on recipient cells and its role in promoting aggressiveness. Treatment of normal fibroblasts with FN-RMS-derived exosomes resulted in a significant uptake of miR-1246 paired with an increase in cell proliferation, migration, and invasion. In turn, delivery of miR-1246-mimic lipoplexes promoted fibroblast proliferation, migration, and invasion in a similar manner. Conversely, when silencing miR-1246 in FN-RMS cells, the resulting derived exosomes demonstrated reversed effects on recipient cells' phenotype. Delivery of exosomal miR-1246 targets GSK3ß and promotes ß-catenin nuclear accumulation, suggesting a deregulation of the Wnt pathway, known to be important in tumor progression. Finally, a pilot clinical study highlighted, for the first time, the presence of high exosomal miR-1246 levels in RMS patients' sera. Altogether, our results demonstrate that exosomal miR-1246 has the potential to alter the tumor microenvironment of FN-RMS cells, suggesting its potential role in promoting oncogenesis.

18.
Int J Cancer ; 133(7): 1589-602, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23553037

RESUMEN

Acquisition of resistance to aromatase inhibitors (AIs) remains a major drawback in the treatment of estrogen receptor alpha (ERα)-positive breast cancers. The Res-Ana cells, a new model of acquired resistance to anastrozole, were established by long-term exposure of aromatase-overexpressing MCF-7 cells to this drug. These resistant cells developed ER-independent mechanisms of resistance and decreased sensitivity to the AI letrozole or to ERα antagonists. They also displayed a constitutive activation of the PI3K/Akt/mTOR pathway and a deregulated expression of several ErbB receptors. An observed increase in the phospho-Akt/Akt ratio between primary and matched recurrent breast tumors of patients who relapsed under anastrozole adjuvant therapy also argued for a pivotal role of the Akt pathway in acquired resistance to anastrozole. Ectopic overexpression of constitutively active Akt1 in control cells was sufficient to induce de novo resistance to anastrozole. Strikingly, combining anastrozole with the highly selective and allosteric Akt inhibitor MK-2206 or with the mTOR inhibitor rapamycin increased sensitivity to this AI in the control cells and was sufficient to overcome resistance and restore sensitivity to endocrine therapy in the resistant cells. Our findings lead to us proposing a model of anastrozole-acquired resistance based on the selection of cancer-initiating-like cells possessing self-renewing properties, intrinsic resistance to anastrozole and sensitivity to MK-2206. Altogether, our work demonstrated that the Akt/mTOR pathway plays a key role in resistance to anastrozole and that combining anastrozole with Akt/mTOR pathway inhibitors represents a promising strategy in the clinical management of hormone-dependent breast cancer patients.


Asunto(s)
Inhibidores de la Aromatasa/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Compuestos Heterocíclicos con 3 Anillos/farmacología , Nitrilos/farmacología , Triazoles/farmacología , Anastrozol , Antineoplásicos Hormonales/farmacología , Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos , Receptores ErbB/biosíntesis , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Células MCF-7 , Recurrencia Local de Neoplasia/metabolismo , Nitrilos/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor ErbB-2/biosíntesis , Receptor ErbB-3/biosíntesis , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo , Triazoles/uso terapéutico
19.
Br J Cancer ; 107(4): 612-6, 2012 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-22828607

RESUMEN

BACKGROUND: To investigate, retrospectively, the role of tumour histotype and antiangiogenic drugs for venous thromboembolism (VTE) development in advanced cancer patients treated in phase I studies. METHODS: Patients enrolled and treated in phase I studies conducted by SENDO (Southern Europe New Drugs Organisation) were considered. RESULTS: Data of 1415 patients were included in the analysis: 526 (37.2%) patients were males, median age was 57.3 years (range: 13-85). Fifty-six (3.96%) patients developed a VTE. At multivariate analysis gynaecologic (hazard ratio (HR): 2.8, 95% confidence interval (CI): 1.29-6.23, P=0.009) and gastrointestinal tumours (HR: 3.23, 95% CI: 1.18-8.87, P=0.023) as well as combination regimens of cytotoxic and antiangiogenic agents (HR: 2.6, 95% CI: 1.11-6.30, P=0.028), white blood cell >11,000 µl(-1) (HR: 2.59, 95% CI: 1.10-6.09, P=0.028) and haemoglobin<10 g dl(-1) (HR: 3.1, 95% CI: 1.07-8.94, P=0.037) were statistically correlated with VTE development. Venous thromboembolism was the fourth most common cause of drug discontinuation. The median time from first drug administration to discontinuation was 1.4 for VTE and 2.3 months for the other adverse events (P=0.02). CONCLUSION: Venous thromboembolism is a relatively common complication among patients treated in the context of phase I studies, and may lead to early drug discontinuation. A greater risk of developing VTE is associated with the diagnosis of gynaecologic and gastrointestinal tumours and the combined use of chemotherapy and antiangiogenic drugs.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ensayos Clínicos Fase I como Asunto , Neoplasias/tratamiento farmacológico , Tromboembolia Venosa/inducido químicamente , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Humanos , Incidencia , Leucocitosis/inducido químicamente , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Estudios Retrospectivos , Riesgo , Adulto Joven
20.
Ann Oncol ; 23(6): 1416-21, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22052988

RESUMEN

BACKGROUND: To investigate the incidence, risk factors and clinical implications of venous thromboembolism (VTE) in advanced cancer patients treated in phase I studies. PATIENTS AND METHODS: Patients enrolled and treated in phase I studies conducted by SENDO (Southern Europe New Drugs Organization) Foundation between 2000 and 2010 in 15 experimental centers were considered for the study. Clinical data, including adverse events, were prospectively collected during the studies and retrospectively pooled for VTE analysis. RESULTS: Data of 1415 patients were considered for analysis. Five hundred and twenty-six (37.2%) patients were males, and median age was 57.3 years (range: 13-85). Eighty-five percent of patients had metastatic disease, while the remaining had locally advanced irresectable disease. For 706 (49.9%) of the patients, the study treatment was with cytotoxic agent(s) only, for 314 with target therapy(ies) only, while the remaining patients received a target therapy in combination with a cytotoxic drug. Fifty-six (3.96%) patients who developed a VTE, almost all (89.3%) during the course of treatment, the remaining during the follow-up. At univariate analysis, the Khorana score, the combination of an antiangiogenic agent with a cytotoxic drug, and the time from first cancer diagnosis to study entry (as continuous variable) were associated with a statistically significant increase of VTE occurrence. The multivariate analysis confirmed only a statistically significant association for the Khorana score. The hazard ratio of VTE occurrence was 7.88 [95% confidence interval (CI) 2.86-21.70) and 2.74 (95% CI 1.27-5.92) times higher for the highest (≥3) and intermediate (1-2) scores as compared with score = 0. CONCLUSIONS: VTE is a relatively common complication among patients treated in the context of phase I studies. The Khorana score predicts VTE development and can be used to identify patients at high of VTE.


Asunto(s)
Antineoplásicos/efectos adversos , Neoplasias/tratamiento farmacológico , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Ensayos Clínicos Fase I como Asunto , Europa (Continente) , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
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