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1.
Nature ; 552(7684): 235-238, 2017 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-29239352

RESUMEN

The most viscous volcanic melts and the largest explosive eruptions on our planet consist of calcalkaline rhyolites. These eruptions have the potential to influence global climate. The eruptive products are commonly very crystal-poor and highly degassed, yet the magma is mostly stored as crystal mushes containing small amounts of interstitial melt with elevated water content. It is unclear how magma mushes are mobilized to create large batches of eruptible crystal-free magma. Further, rhyolitic eruptions can switch repeatedly between effusive and explosive eruption styles and this transition is difficult to attribute to the rheological effects of water content or crystallinity. Here we measure the viscosity of a series of melts spanning the compositional range of the Yellowstone volcanic system and find that in a narrow compositional zone, melt viscosity increases by up to two orders of magnitude. These viscosity variations are not predicted by current viscosity models and result from melt structure reorganization, as confirmed by Raman spectroscopy. We identify a critical compositional tipping point, independently documented in the global geochemical record of rhyolites, at which rhyolitic melts fluidize or stiffen and that clearly separates effusive from explosive deposits worldwide. This correlation between melt structure, viscosity and eruptive behaviour holds despite the variable water content and other parameters, such as temperature, that are inherent in natural eruptions. Thermodynamic modelling demonstrates how the observed subtle compositional changes that result in fluidization or stiffening of the melt can be induced by crystal growth from the melt or variation in oxygen fugacity. However, the rheological effects of water and crystal content alone cannot explain the correlation between composition and eruptive style. We conclude that the composition of calcalkaline rhyolites is decisive in determining the mobilization and eruption dynamics of Earth's largest volcanic systems, resulting in a better understanding of how the melt structure controls volcanic processes.

2.
Ann Oncol ; 26(5): 1012-1018, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25669829

RESUMEN

BACKGROUND: We carried out a phase I trial of the vascular endothelial growth factor inhibitor pazopanib and the histone deacetylase inhibitor vorinostat to determine the safety and efficacy. Because these agents are known to target factors activated by TP53 mutation and facilitate mutant p53 degradation, a subgroup analysis may be interesting in patients with TP53 mutant malignancies. PATIENTS AND METHODS: Patients with advanced solid tumors (n = 78) were enrolled following a 3 + 3 design, with dose expansion for those with responsive tumors. Hotspot TP53 mutations were tested when tumor specimens were available. RESULTS: Adverse events of ≥grade 3 included thrombocytopenia, neutropenia, fatigue, hypertension, diarrhea and vomiting. Overall, the treatment produced stable disease for at least 6 months or partial response (SD ≥6 months/PR) in 19% of the patients, median progression-free survival (PFS) of 2.2 months, and median overall survival (OS) of 8.9 months. In patients with detected hotspot TP53 mutant advanced solid tumors (n = 11), the treatment led to a 45% rate of SD ≥6 months/PR (1 PR and 3 SD ≥6 months), median PFS of 3.5 months, and median OS of 12.7 months, compared favorably with the results for patients with undetected hotspot TP53 mutations (n = 25): 16% (1 PR and 3 SD ≥6 months, P = 0.096), 2.0 months (P = 0.042), and 7.4 months (P = 0.1), respectively. CONCLUSION: The recommended phase II dosage was oral pazopanib at 600 mg daily plus oral vorinostat at 300 mg daily. The preliminary evidence supports further evaluation of the combination in cancer patients with mutated TP53, especially in those with metastatic sarcoma or metastatic colorectal cancer. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov, NCT01339871.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de Histona Desacetilasas/administración & dosificación , Ácidos Hidroxámicos/administración & dosificación , Mutación , Neoplasias/tratamiento farmacológico , Neovascularización Patológica , Pirimidinas/administración & dosificación , Sulfonamidas/administración & dosificación , Proteína p53 Supresora de Tumor/genética , Administración Oral , Adolescente , Adulto , Anciano , Inhibidores de la Angiogénesis/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Inhibidores de Histona Desacetilasas/efectos adversos , Humanos , Ácidos Hidroxámicos/efectos adversos , Indazoles , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias/irrigación sanguínea , Neoplasias/genética , Neoplasias/mortalidad , Neoplasias/patología , Modelos de Riesgos Proporcionales , Estabilidad Proteica , Proteolisis , Pirimidinas/efectos adversos , Sulfonamidas/efectos adversos , Texas , Factores de Tiempo , Resultado del Tratamiento , Proteína p53 Supresora de Tumor/metabolismo , Vorinostat , Adulto Joven
3.
BMC Cancer ; 15: 713, 2015 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-26474549

RESUMEN

BACKGROUND: This retrospective study aims to investigate the activity of retreatment with anti-EGFR-based therapies in order to explore the concept of clonal evolution by evaluating the impact of prior activity and intervening time interval. METHODS: Eighty-nine KRAS exon 2-wild-type metastatic colorectal patients were retreated on phase I/II clinical trials containing anti-EGFR therapies after progressing on prior cetuximab or panitumumab. Response on prior anti-EGFR therapy was defined retrospectively per physician-records as response or stable disease ≥6 months. Multivariable statistical methods included a multiple logistic regression model for response, and Cox proportional hazards model for progression-free survival. RESULTS: Retreatment anti-EGFR agents were cetuximab (n = 76) or cetuximab plus erlotinib (n = 13). The median interval time between prior and retreatment regimens was 4.57 months (range: 0.46-58.7). Patients who responded to the prior cetuximab or panitumumab were more likely to obtain clinical benefit to the retreatment compared to the non-responders in both univariate (p = 0.007) and multivariate analyses (OR: 3.38, 95 % CI: 1.27, 9.31, p = 0.019). The clinical benefit rate on retreatment also showed a marginally significant association with interval time between the two anti-EGFR based therapies (p = 0.053). Median progression-free survival on retreatment was increased in prior responders (4.9 months, 95 % CI: 3.6, 6.2) compared to prior non-responders (2.5 months, 95 % CI, 1.58, 3.42) in univariate (p = 0.064) and multivariate analysis (HR: 0.70, 95 % CI: 0.43-1.15, p = 0.156). CONCLUSION: Our data lends support to the concept of clonal evolution, though the clinical impact appears less robust than previously reported. Further work to determine which patients benefit from retreatment post progression is needed.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Receptores ErbB/genética , Adulto , Anciano , Cetuximab/administración & dosificación , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Receptores ErbB/antagonistas & inhibidores , Clorhidrato de Erlotinib/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Panitumumab , Proteínas Proto-Oncogénicas p21(ras)/genética , Retratamiento
4.
Ann Oncol ; 25(1): 276-82, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24356639

RESUMEN

BACKGROUND: New targeted agents may cause acute cardiac events. The purpose of our study was to investigate the incidence and the prognostic significance of left ventricular ejection fraction (LVEF) in phase I trials. PATIENTS AND METHODS: Between October 2008 and September 2011, the records of 1166 consecutive patients with advanced cancer treated in the Phase I Clinic who underwent echocardiography were retrospectively reviewed. RESULTS: Most of the patients were White (78%), and the most common tumor types were colorectal cancer and melanoma. Of 1166 patients, 177 (15.2%) patients had an LVEF of <50%. No difference in overall survival (OS) between patients with LVEF ≥ 50% and patients with LVEF < 50% was seen (median OS 7.4 versus 7.0 months, P = 0.84). Patients with LVEF ≤ 35% had shorter survival compared with those with LVEF between 35% and 50% (median 4.2 versus 8.0 months; P = 0.005). In multivariate analysis of patients with LVEF < 50%, independent factors predicting longer survival were LVEF > 35%, ≤2 prior systemic therapies, ≤2 metastatic sites, and normal lactate dehydrogenase and albumin levels. CONCLUSION: Echocardiography would improve patient selection for enrollment in phase I clinical trials. These data suggest that it is safe to treat patients with LVEF between 35% and 50%.


Asunto(s)
Neoplasias/tratamiento farmacológico , Volumen Sistólico , Ensayos Clínicos Fase I como Asunto , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasias/mortalidad , Neoplasias/fisiopatología , Selección de Paciente , Pronóstico , Estudios Retrospectivos
5.
Nature ; 453(7194): 507-10, 2008 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-18497822

RESUMEN

Volcanic dome-building episodes commonly exhibit acceleration in both effusive discharge rate and seismicity before explosive eruptions. This should enable the application of material failure forecasting methods to eruption forecasting. To date, such methods have been based exclusively on the seismicity of the country rock. It is clear, however, that the rheology and deformation rate of the lava ultimately dictate eruption style. The highly crystalline lavas involved in these eruptions are pseudoplastic fluids that exhibit a strong component of shear thinning as their deformation accelerates across the ductile to brittle transition. Thus, understanding the nature of the ductile-brittle transition in dome lavas may well hold the key to an accurate description of dome growth and stability. Here we present the results of rheological experiments with continuous microseismic monitoring, which reveal that dome lavas are seismogenic and that the character of the seismicity changes markedly across the ductile-brittle transition until complete brittle failure occurs at high strain rates. We conclude that magma seismicity, combined with failure forecasting methods, could potentially be applied successfully to dome-building eruptions for volcanic forecasting.

7.
Ann Oncol ; 24(10): 2515-2521, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23798614

RESUMEN

BACKGROUND: Cancer stem cells (CSCs) are epithelial tumor cells that express CD44(+)CD24(-/lo). CSCs can be further divided into those that have aldehyde dehydrogenase (ALDH) activity (Aldefluor(+)) and those that do not. We hypothesized that if CSCs are responsible for tumor dissemination, their presence in bone marrow (BM) would be prognostic in early stages of breast cancer (EBC) patients. PATIENTS AND METHODS: BM aspirates were collected at the time of surgery from 108 patients with EBC. BM was analyzed for CSCs and ALDH activity by flow cytometry. Overall survival and disease-free survival (DFS) were calculated from the date of diagnosis and analyzed with Kaplan-Meier survival plots. Cox multivariate proportional hazards model was also carried out. RESULTS: Patients with CSCs in BM had a hazard ratio (HR) of 8.8 for DFS (P = 0.002); patients with Aldefluor(+) CSCs had a HR of 5.9 (P = 0.052) for DFS. All deceased patients (n = 7) had CSCs in BM. In multivariate analysis, the presence of CSCs in BM was a prognostic factor of DFS (HR = 15.8, P = 0.017). CONCLUSIONS: The presence of BM metastasis is correlated with CSCs and these CSCs irrespective of ALDH activity are an independent adverse prognostic factor in EBC patients.


Asunto(s)
Aldehído Deshidrogenasa/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Células Madre Neoplásicas/patología , Aldehído Deshidrogenasa/análisis , Células de la Médula Ósea/patología , Antígeno CD24/metabolismo , Supervivencia sin Enfermedad , Femenino , Humanos , Receptores de Hialuranos/metabolismo , Metástasis de la Neoplasia , Células Neoplásicas Circulantes/patología , Análisis de Supervivencia
8.
Breast Cancer Res Treat ; 138(2): 591-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23460246

RESUMEN

The purpose of this study was to assess the prognostic impact of age in patients with triple-negative breast cancer (TNBC). 1,732 patients with primary TNBC were analyzed. Five age cohorts (≤30, 31-40, 41-50, 51-60, and >60 years) at diagnosis were correlated with clinical/pathological parameters. Univariate and multivariate analyses were used to examine the effect of age on disease-free (DFS), distant disease-free (DDFS), and overall survival (OS). In patients with TNBC, increasing age at diagnosis was inversely correlated with tumor grade (P < 0.0001); likelihood of being non-Caucasian (P = 0.0001); likelihood of getting chemotherapy (P < 0.0001); and positively correlated with DFS (P = 0.0003); DDFS (P < 0.0001); and OS (P < 0.0001). The median DFS for patients 31-40 and older than 60 years was 4 years [95 % confidence interval (95 % CI) 2-5] and 8 years (95 % CI 5-14, respectively, P = 0.0003). The DDFS and OS were also statistically significantly shorter for younger patients. In multivariate analysis, tumor size, nodal stage, tumor grade, and age remained significant independent prognostic variables. Clinical characteristics of TNBC differ by age group, patients ≤40 years have poorer survival despite more aggressive systemic therapy.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Adulto , Factores de Edad , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estadísticas no Paramétricas , Resultado del Tratamiento
9.
Sci Rep ; 13(1): 14435, 2023 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-37660204

RESUMEN

The 15 January 2022 submarine eruption at Hunga volcano was the most explosive volcanic eruption in 140 years. It involved exceptional magma and seawater interaction throughout the entire submarine caldera collapse. The submarine volcanic jet breached the sea surface and formed a subaerial eruptive plume that transported volcanic ash, gas, sea salts and seawater up to ~ 57 km, reaching into the mesosphere. We document high concentrations of sea salts in tephra (volcanic ash) collected shortly after deposition. We also discuss the potential climatic consequences of large-scale injection of salts into the upper atmosphere during submarine eruptions. Sodium chloride in these volcanic plumes can reach extreme concentrations, and dehalogenation of chlorides and bromides poses the risk of long-term atmospheric and weather impact. Salt content in rapidly collected tephra samples may also be used as a proxy to estimate the water:magma ratio during eruption, with implications for quantification of fragmentation efficiency in submarine breaching events. The balance between salt loading into the atmosphere versus deposition in ash aggregates is a key factor in understanding the atmospheric and climatic consequences of submarine eruptions.

10.
Diabetologia ; 55(4): 1103-13, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21918806

RESUMEN

AIMS/HYPOTHESIS: Impaired fibrin clot lysis is a key abnormality in diabetes and complement C3 is one protein identified in blood clots. This work investigates the mechanistic pathways linking C3 and hypofibrinolysis in diabetes using ex vivo/in vitro studies. METHODS: Fibrinolysis and C3 plasma levels were determined in type 1 diabetic patients and healthy controls, and the effects of glycaemia investigated. C3 incorporation into fibrin clots and modulation of fibrinolysis were analysed by ELISA, immunoblotting, turbidimetric assays and electron and confocal microscopy. RESULTS: Clot lysis time was longer in diabetic children than in controls (599 ± 18 and 516 ± 12 s respectively; p < 0.01), C3 levels were higher in diabetic children (0.55 ± 0.02 and 0.43 ± 0.02 g/l respectively; p < 0.01) and both were affected by improving glycaemia. An interaction between C3 and fibrin was confirmed by the presence of lower protein levels in sera compared with corresponding plasma and C3 detection in plasma clots by immunoblot. In a purified system, C3 was associated with thinner fibrin fibres and more prolongation of lysis time of clots made from fibrinogen from diabetic participants compared with controls (244 ± 64 and 92 ± 23 s respectively; p < 0.05). Confocal microscopy showed higher C3 incorporation into diabetic clots compared with controls, and fully formed clot lysis was prolonged by 764 ± 76 and 428 ± 105 s respectively (p < 0.05). Differences in lysis, comparing diabetes and controls, were not related to altered plasmin generation or C3-fibrinogen binding assessed by plasmon resonance. CONCLUSIONS/INTERPRETATION: C3 incorporation into clots from diabetic fibrinogen is enhanced and adversely affects fibrinolysis. This may be one novel mechanism for compromised clot lysis in diabetes, potentially offering a new therapeutic target.


Asunto(s)
Trastornos de la Coagulación Sanguínea/etiología , Complemento C3/metabolismo , Diabetes Mellitus Tipo 1/complicaciones , Fibrina/metabolismo , Fibrinógeno/metabolismo , Fibrinólisis/fisiología , Adolescente , Adulto , Trastornos de la Coagulación Sanguínea/metabolismo , Pruebas de Coagulación Sanguínea , Estudios de Casos y Controles , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Humanos , Masculino
11.
Breast Cancer Res Treat ; 135(2): 619-27, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22890751

RESUMEN

We examined whether baseline Ki67 expression in estrogen receptor-positive (ER+) primary breast cancer correlates with clinical benefit and time to progression on first-line endocrine therapy and survival in metastatic disease. Ki67 values and outcome information were retrieved from a prospectively maintained clinical database and validated against the medical records; 241 patients with metastatic breast cancer were included--who had ER+ primary cancer with known Ki67 expression level--and received first-line endocrine therapy for metastatic disease. Patients were assigned to low (<10 %), intermediate (10-25 %), or high (>25 %) Ki67 expression groups. Kaplan-Meier survival curves were plotted and multivariate analysis was performed to assess association between clinical and immunohistochemical variables and outcome. The clinical benefit rates were 81, 65, and 55 % in the low (n = 32), intermediate (n = 103), and high (n = 106) Ki67 expression groups (P = 0.001). The median times to progression on first-line endocrine therapy were 20.3 (95 % CI, 17.5-38.5), 10.8 (95 % CI, 8.9-18.8), and 8 (95 % CI, 6.1-11.1) months, respectively (P = 0.0002). The median survival times after diagnosis of metastatic disease were also longer for the low/intermediate compared to the high Ki67 group, 52 versus 30 months (P < 0.0001). In multivariate analysis, high Ki67 expression in the primary tumor remained an independent adverse prognostic factor in metastatic disease (P = 0.001). Low Ki67 expression in the primary tumor is associated with higher clinical benefit and longer time to progression on first-line endocrine therapy and longer survival after metastatic recurrence.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama Masculina/metabolismo , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Antígeno Ki-67/metabolismo , Recurrencia Local de Neoplasia/prevención & control , Neoplasias Hormono-Dependientes/metabolismo , Receptores de Estrógenos/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Neoplasias de la Mama Masculina/tratamiento farmacológico , Neoplasias de la Mama Masculina/mortalidad , Neoplasias de la Mama Masculina/patología , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/secundario , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias Hormono-Dependientes/mortalidad , Neoplasias Hormono-Dependientes/patología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Resultado del Tratamiento
12.
Ann Oncol ; 22(11): 2387-2393, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21406473

RESUMEN

BACKGROUND: Recent retrospective studies have suggested that patients with T1a,bN0M0 human epidermal growth factor receptor 2 (HER2)-positive breast cancer are at a higher risk for recurrence and might benefit from adjuvant trastuzumab. The absolute benefits associated with treating this subgroup are uncertain. DESIGN: We reviewed recent studies examining the prognostic value of HER2 in patients with node-negative T1a,b HER2-positive breast cancer. We calculated the number needed to treat (NNT) using baseline risk estimates for untreated T1a,bN0M0 breast cancer and the number needed to harm (NNH) using the incidence of cardiac events in each of the adjuvant trastuzumab clinical trials. RESULTS: Several studies were identified, each with limitations inherent to retrospective database analyses: small cohort sizes, lack of systematic HER2 testing in older specimens, variations in the use of adjuvant therapy and definitions of study end points, and lack of information relating to comorbidities. The 5-year disease-free survival in the pre-trastuzumab era ranged from 77% to 95%. Comparisons between small HER2 -positive and small HER2 -negative cancers showed numerically worse outcome for the HER2-positive cohort in some but not all studies. In many instances, the NNH was larger (26-250) than the NNT (13-35); however, in a subset of patients, the NNH was lower (6) than the NNT (13-35). CONCLUSIONS: Better prediction tools to estimate more precisely the risk for death due to comorbid illness versus breast cancer are needed. In some patients, the risks of therapy could outweigh the benefits. Treatment selection for T1a,bN0 HER2-positive cancers remains in the transition area between evidence- and subjective judgment-based medicine.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/biosíntesis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/enzimología , Receptor ErbB-2/biosíntesis , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Toma de Decisiones , Femenino , Humanos , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Trastuzumab , Incertidumbre
13.
Int J Obes (Lond) ; 35(8): 1031-40, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21042321

RESUMEN

OBJECTIVE: Neprilysin (NEP), a zinc metalloendopeptidase, has a role in blood pressure control and lipid metabolism. The present study tested the hypothesis that NEP is associated with insulin resistance and features of the metabolic syndrome (MetS) in a study of 318 healthy human subjects and in murine obesity, and investigated NEP production by adipocytes in-vitro. METHODS AND RESULTS: In 318 white European males, plasma NEP was elevated in the MetS and increased progressively with increasing MetS components. Plasma NEP activity correlated with insulin, homoeostasis model assessment and body mass index (BMI) in all subjects (P<0.01). Quantitative reverse transcriptase PCR (RT-PCR) and western blotting showed that in human pre-adipocytes NEP expression is upregulated 25- to 30-fold during differentiation into adipocytes. Microarray analysis of mRNA from differentiated human adipocytes confirmed high-NEP expression comparable with adiponectin and plasminogen activator inhibitor-1. In a murine model of diet-induced insulin resistance, plasma NEP levels were significantly higher in high-fat diet (HFD)-fed compared with normal chow diet (NCD)-fed animals (1642 ± 529 and 820 ± 487 pg µl(-1), respectively; P<0.01). Tissue NEP was increased in mesenteric fat in HFD compared with NCD-fed mice (P<0.05). NEP knockout mice did not display any changes in insulin resistance, glucose tolerance, or body and epididymal fat pad weight compared with wild-type mice. CONCLUSION: In humans, NEP activity correlated with BMI and measures of insulin resistance with increasing levels in subjects with multiple cardiovascular risk factors. NEP protein production in human adipocytes increased during cell differentiation and plasma and adipose tissue levels of NEP were increased in obese insulin-resistant mice. Our results indicate that NEP associates with cardiometabolic risk in the presence of insulin resistance and increases with obesity.


Asunto(s)
Adipocitos/metabolismo , Índice de Masa Corporal , Enfermedades Cardiovasculares/enzimología , Resistencia a la Insulina , Síndrome Metabólico/enzimología , Neprilisina/metabolismo , Obesidad/enzimología , Animales , Western Blotting , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/fisiopatología , Niño , Grasas de la Dieta/administración & dosificación , Humanos , Masculino , Síndrome Metabólico/etiología , Síndrome Metabólico/fisiopatología , Ratones , Ratones Noqueados , Neprilisina/sangre , Neprilisina/genética , Obesidad/complicaciones , Obesidad/fisiopatología , Análisis por Matrices de Proteínas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
ESMO Open ; 6(2): 100079, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33721621

RESUMEN

BACKGROUND: Preclinical studies suggest that combining vandetanib (VAN), a multi-tyrosine kinase inhibitor of rearranged during transfection (RET) proto-oncogene, vascular endothelial growth factor receptor (VEGFR), and epidermal growth factor receptor (EGFR), with everolimus (EV), a mammalian target of rapamycin (mTOR) inhibitor, may improve antitumor activity. We determined the safety, maximum tolerated dose (MTD), recommended phase II dose (RP2D), and dose-limiting toxicities (DLTs) of VAN + EV in patients with advanced solid cancers and the effect of combination therapy on cancer cell proliferation and intracellular pathways. PATIENTS AND METHODS: Patients with refractory solid tumors were enrolled in a phase I dose-escalation trial testing VAN (100-300 mg orally daily) + EV (2.5-10 mg orally daily). Objective responses were evaluated using RECIST v1.1. RET mutant cancer cell lines were used in cell-based studies. RESULTS: Among 80 patients enrolled, 72 (90%) patients were evaluable: 7 achieved partial response (PR) (10%) and 37 had stable disease (SD) (51%; duration range: 1-27 cycles). Clinical benefit (SD or PR ≥ 6 months) was observed in 26 evaluable patients [36%, 95% confidence intervals (CI) (25% to 49%)]. In 80 patients, median overall survival (OS) was 10.5 months [95% CI (8.5-16.1)] and median progression-free survival (PFS) 4.1 months [95% CI (3.4-7.3)]. Six patients (7.5%) experienced DLTs and 20 (25%) required dose modifications. VAN + EV was safe, with fatigue, rash, diarrhea, and mucositis being the most common toxicities. In cell-based studies, combination therapy was superior to monotherapy at inhibiting cancer cell proliferation and intracellular signaling. CONCLUSIONS: The MTDs and RP2Ds of VAN + EV are 300 mg and 10 mg, respectively. VAN + EV combination is safe and active in refractory solid tumors. Further investigation is warranted in RET pathway aberrant tumors.


Asunto(s)
Everolimus , Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Everolimus/efectos adversos , Humanos , Neoplasias/tratamiento farmacológico , Piperidinas , Proto-Oncogenes Mas , Quinazolinas , Factor A de Crecimiento Endotelial Vascular/uso terapéutico
15.
Br J Cancer ; 101(4): 615-20, 2009 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-19672263

RESUMEN

BACKGROUND: Because of the poor outcomes for patients with recurrent glioblastoma multiforme (GBM), and some laboratory and clinical evidence of efficacy using interferon in GBM, we assessed the toxicity and efficacy of temozolomide (TMZ) combined with either short-acting (IFN) or long-acting (pegylated) interferon alpha2b (PEG) in two single-arm phase II studies, and compared the results to 6-month progression-free survival (PFS-6) data from historical controls. METHODS: Two single-arm phase II studies were carried out in adults with GBM. Patients were treated with the standard regimen of TMZ (150-200 mg m(-2) per day x 5 days every month) combined with either 4 million units per m(2) subcutaneously (SQ) three times weekly of IFN or 0.5 microg kg(-1) SQ weekly of PEG. Physical exams and imaging evaluations were carried out every 8 weeks. RESULTS: On the IFN study, 34 adults (74% men) were enrolled, and 29 adults (55% men) on the PEG study; median Karnofsky performance status was 80 and 90 for the IFN and PEG studies, respectively. Grade 3 or 4 toxicities were common, leucopoenia and thrombocytopoenia occurring in 35-38% and 18-21% of patients, respectively. Grade 3 or 4 fatigue occurred in 18% of patients on both studies. Lymphopoenia was infrequent. PFS-6 was 31% for 29 evaluable patients in the IFN study and 38% for 26 evaluable patients in the PEG study. CONCLUSION: In recurrent GBM patients, both studies of standard dose TMZ with either IFN or PEG showed improved efficacy when compared to historical controls, or reports using TMZ alone. Even though the TMZ+PEG study met criteria for further study, the results of both of these studies must be considered in light of the standard of care (TMZ plus radiotherapy) for newly diagnosed GBM, which has evolved since the inception of these studies. Despite the results of the current studies being eclipsed by the new GBM standard of care, these results can still inform the development of newer approaches for GBM, either in an earlier, upfront setting, or by extrapolation of the results and consideration of the use of PEG or IFN in conjunction with other antiglioma strategies.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adolescente , Adulto , Anciano , Dacarbazina/administración & dosificación , Dacarbazina/efectos adversos , Dacarbazina/análogos & derivados , Supervivencia sin Enfermedad , Femenino , Humanos , Interferón Tipo I/administración & dosificación , Interferón Tipo I/efectos adversos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferón-alfa/efectos adversos , Estimación de Kaplan-Meier , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Polietilenglicoles/efectos adversos , Proteínas Recombinantes , Temozolomida , Resultado del Tratamiento , Adulto Joven
16.
Oncogene ; 26(17): 2435-44, 2007 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-17043651

RESUMEN

Signal transducer and activator of transcription-3 (STAT3) is constitutively activated in a variety of cancer types, including malignant gliomas. STAT3 is activated by phosphorylation of a tyrosine residue, after which it dimerizes and translocates into the nucleus. There it regulates the expression of several genes responsible for proliferation and survival at the transcriptional level. A selective inhibitor of STAT3 phosphorylation, AG490, has been shown to inhibit growth and induce apoptosis in some cancer cell types. However, although AG490 routinely shows in vitro anticancer activity, it has not consistently demonstrated an in vivo anticancer effect in animal models. Here, we have tested WP1066, a novel inhibitor structurally related to AG490 but significantly more potent and active, against human malignant glioma U87-MG and U373-MG cells in vitro and in vivo. IC(50) values for WP1066 were 5.6 muM in U87-MG cells and 3.7 muM in U373-MG cells, which represents 18-fold and eightfold increases in potency, respectively, over that of AG490. WP1066 activated Bax, suppressed the expression of c-myc, Bcl-X(L) and Mcl-1, and induced apoptosis. Systemic intraperitoneal administration of WP1066 in mice significantly (P<0.001) inhibited the growth of subcutaneous malignant glioma xenografts during the 30-day follow-up period. Immunohistochemical analysis of the excised tumors revealed that phosphorylated STAT3 levels in the WP1066 treatment group remained inhibited at 3 weeks after the final WP1066 injection, whereas tumors from the control group expressed high levels of phosphorylated STAT3. We conclude that WP1066 holds promise as a therapeutic agent against malignant gliomas.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Glioma/tratamiento farmacológico , Glioma/patología , Piridinas/farmacología , Factor de Transcripción STAT3/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Tirfostinos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Humanos , Piridinas/química , Factor de Transcripción STAT3/fisiología , Transducción de Señal/fisiología , Tirfostinos/química
17.
Gene Ther ; 15(17): 1233-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18580968

RESUMEN

Oncolytic adenoviruses are a promising tool in cancer therapy. In this study, we characterized the role of autophagy in oncolytic adenovirus-induced therapeutic effects. OBP-405, an oncolytic adenovirus regulated by the human telomerase reverse transcriptase promoter (hTERT-Ad, OBP-301) with a tropism modification (RGD) exhibited a strong antitumor effect on glioblastoma cells. When autophagy was inhibited pharmacologically, the cytotoxicity of OBP-405 was attenuated. In addition, autophagy-deficient Atg5(-/-) mouse embryonic fibroblasts (MEFs) were less sensitive than wild-type MEFs to OBP-405. These findings indicate that OBP-405-induced autophagy is a cell killing effect. Moreover, autophagy-inducing therapies (temozolomide and rapamycin) synergistically sensitized tumor cells to OBP-405 by stimulating the autophagic pathway without altering OBP-405 replication. Mice harboring intracranial tumors treated with OBP-405 and temozolomide survived significantly longer than those treated with temozolomide alone, and mice treated with OBP-405 and the rapamycin analog RAD001 survived significantly longer than those treated with RAD001 alone. The observation that autophagy inducers increase OBP-405 antitumor activity suggests a novel strategy for treating patients with glioblastoma.


Asunto(s)
Autofagia/efectos de los fármacos , Neoplasias Encefálicas/terapia , Terapia Genética/métodos , Glioblastoma/terapia , Viroterapia Oncolítica/métodos , Adenoviridae/genética , Animales , Línea Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Ratones , Virus Oncolíticos/genética , Sirolimus/uso terapéutico , Temozolomida
18.
J Phys Chem B ; 112(43): 13608-19, 2008 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-18831567

RESUMEN

The rapid advancement of nanotechnology has created a vast array of engineered nanomaterials (ENMs) which have unique physical (size, shape, crystallinity, surface charge) and chemical (surface coating, elemental composition and solubility) attributes. These physicochemical properties of ENMs can produce chemical conditions to induce a pro-oxidant environment in the cells, causing an imbalanced cellular energy system dependent on redox potential and thereby leading to adverse biological consequences, ranging from the initiation of inflammatory pathways through to cell death. The present study was designed to evaluate size-dependent cellular interactions of known biologically active silver nanoparticles (NPs, Ag-15 nm, Ag-30 nm, and Ag-55 nm). Alveolar macrophages provide the first defense and were studied for their potential role in initiating oxidative stress. Cell exposure produced morphologically abnormal sizes and adherence characteristics with significant NP uptake at high doses after 24 h. Toxicity evaluations using mitochondrial and cell membrane viability along with reactive oxygen species (ROS) were performed. After 24 h of exposure, viability metrics significantly decreased with increasing dose (10-75 microg/mL) of Ag-15 nm and Ag-30 nm NPs. A more than 10-fold increase of ROS levels in cells exposed to 50 microg/mL Ag-15 nm suggests that the cytotoxicity of Ag-15 nm is likely to be mediated through oxidative stress. In addition, activation of the release of traditional inflammatory mediators were examined by measuring levels of cytokines/chemokines, including tumor necrosis factor (TNF-alpha), macrophage inhibitory protein (MIP-2), and interleukin-6 (IL-6), released into the culture media. After 24 h of exposure to Ag-15 nm nanoparticles, a significant inflammatory response was observed by the release of TNF-alpha, MIP-2, and IL-1beta. However, there was no detectable level of IL-6 upon exposure to silver nanoparticles. In summary, a size-dependent toxicity was produced by silver nanoparticles, and one predominant mechanism of toxicity was found to be largely mediated through oxidative stress.


Asunto(s)
Nanopartículas/química , Nanopartículas/toxicidad , Especies Reactivas de Oxígeno/química , Plata/química , Plata/toxicidad , Animales , Células Cultivadas , Glutatión/metabolismo , Inmunohistoquímica , Inflamación/patología , Exposición por Inhalación , L-Lactato Deshidrogenasa/metabolismo , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Microscopía Electrónica de Rastreo , Microscopía de Contraste de Fase , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Estrés Oxidativo , Tamaño de la Partícula , Ratas , Soluciones
19.
New Microbes New Infect ; 21: 102-104, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29541477

RESUMEN

Coprinopsis cinerea is an environmental fungus which can cause disseminated infections in immunocompromised patients, often leading to death. Here we report the case of a paediatric patient with an invasive wound infection due to C. cinerea, which was successfully treated with surgical debridement and oral posaconazole.

20.
J Phys Condens Matter ; 30(23): 235401, 2018 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-29701605

RESUMEN

Applying neutron powder diffraction, four unique hydrogen positions were determined in a rockbridgeite-type compound, [Formula: see text] [Formula: see text]. Its honeycomb-like H-bond network running without interruption along the crystallographic [Formula: see text] axis resembles those in alkali sulphatic and arsenatic oxyhydroxides. They provide the so-called dynamically disordered H-bond network over which protons are superconducting in a vehicle mechanism. This is indicated by dramatic increases of dielectric constant and loss factor at room temperature. The relevance of static and dynamic disorder of OH and HOH groups are explained in terms of a high number of structural defects at octahedral chains alternatingly half-occupied by [Formula: see text] cations. The structure is built up by unusual octahedral doublet, triplet, and quartet clusters of aliovalent 3d transition metal cations, predicting complicate magnetic ordering and interaction. The ferrimagnetic structure below the Curie temperature [Formula: see text]-83 K could be determined from the structure analysis with neutron diffraction data at 25 K.

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