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1.
J Clin Med ; 13(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731055

RESUMEN

Background: to examine factors associated with cardiac evaluation and associations between cardiac test abnormalities and clinical outcomes in patients with acute brain injury (ABI) due to acute ischemic stroke (AIS), spontaneous subarachnoid hemorrhage (SAH), spontaneous intracerebral hemorrhage (sICH), and traumatic brain injury (TBI) requiring neurocritical care. Methods: In a cohort of patients ≥18 years, we examined the utilization of electrocardiography (ECG), beta-natriuretic peptide (BNP), cardiac troponin (cTnI), and transthoracic echocardiography (TTE). We investigated the association between cTnI, BNP, sex-adjusted prolonged QTc interval, low ejection fraction (EF < 40%), all-cause mortality, death by neurologic criteria (DNC), transition to comfort measures only (CMO), and hospital discharge to home using univariable and multivariable analysis (adjusted for age, sex, race/ethnicity, insurance carrier, pre-admission cardiac disorder, ABI type, admission Glasgow Coma Scale Score, mechanical ventilation, and intracranial pressure [ICP] monitoring). Results: The final sample comprised 11,822 patients: AIS (46.7%), sICH (18.5%), SAH (14.8%), and TBI (20.0%). A total of 63% (n = 7472) received cardiac workup, which increased over nine years (p < 0.001). A cardiac investigation was associated with increased age, male sex (aOR 1.16 [1.07, 1.27]), non-white ethnicity (aOR), non-commercial insurance (aOR 1.21 [1.09, 1.33]), pre-admission cardiac disorder (aOR 1.21 [1.09, 1.34]), mechanical ventilation (aOR1.78 [1.57, 2.02]) and ICP monitoring (aOR1.68 [1.49, 1.89]). Compared to AIS, sICH (aOR 0.25 [0.22, 0.29]), SAH (aOR 0.36 [0.30, 0.43]), and TBI (aOR 0.19 [0.17, 0.24]) patients were less likely to receive cardiac investigation. Patients with troponin 25th-50th quartile (aOR 1.65 [1.10-2.47]), troponin 50th-75th quartile (aOR 1.79 [1.22-2.63]), troponin >75th quartile (aOR 2.18 [1.49-3.17]), BNP 50th-75th quartile (aOR 2.86 [1.28-6.40]), BNP >75th quartile (aOR 4.54 [2.09-9.85]), prolonged QTc (aOR 3.41 [2.28; 5.30]), and EF < 40% (aOR 2.47 [1.07; 5.14]) were more likely to be DNC. Patients with troponin 50th-75th quartile (aOR 1.77 [1.14-2.73]), troponin >75th quartile (aOR 1.81 [1.18-2.78]), and prolonged QTc (aOR 1.71 [1.39; 2.12]) were more likely to be associated with a transition to CMO. Patients with prolonged QTc (aOR 0.66 [0.58; 0.76]) were less likely to be discharged home. Conclusions: This large, single-center study demonstrates low rates of cardiac evaluations in TBI, SAH, and sICH compared to AIS. However, there are strong associations between electrocardiography, biomarkers of cardiac injury and heart failure, and echocardiography findings on clinical outcomes in patients with ABI. Findings need validation in a multicenter cohort.

2.
IEEE Trans Vis Comput Graph ; 27(2): 1225-1235, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33048742

RESUMEN

Shaded relief is an effective method for visualising terrain on topographic maps, especially when the direction of illumination is adapted locally to emphasise individual terrain features. However, digital shading algorithms are unable to fully match the expressiveness of hand-crafted masterpieces, which are created through a laborious process by highly specialised cartographers. We replicate hand-drawn relief shading using U-Net neural networks. The deep neural networks are trained with manual shaded relief images of the Swiss topographic map series and terrain models of the same area. The networks generate shaded relief that closely resemble hand-drawn shaded relief art. The networks learn essential design principles from manual relief shading such as removing unnecessary terrain details, locally adjusting the illumination direction to accentuate individual terrain features, and varying brightness to emphasise larger landforms. Neural network shadings are generated from digital elevation models in a few seconds, and a study with 18 relief shading experts found that they are of high quality.


Asunto(s)
Gráficos por Computador , Redes Neurales de la Computación , Algoritmos , Estimulación Luminosa
3.
Nat Commun ; 3: 1241, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23212370

RESUMEN

Many applications proposed for graphene require multiple sheets be assembled into a monolithic structure. The ability to maintain structural integrity upon large deformation is essential to ensure a macroscopic material which functions reliably. However, it has remained a great challenge to achieve high elasticity in three-dimensional graphene networks. Here we report that the marriage of graphene chemistry with ice physics can lead to the formation of ultralight and superelastic graphene-based cellular monoliths. Mimicking the hierarchical structure of natural cork, the resulting materials can sustain their structural integrity under a load of >50,000 times their own weight and can rapidly recover from >80% compression. The unique biomimetic hierarchical structure also provides this new class of elastomers with exceptionally high energy absorption capability and good electrical conductivity. The successful synthesis of such fascinating materials paves the way to explore the application of graphene in a self-supporting, structurally adaptive and 3D macroscopic form.


Asunto(s)
Materiales Biomiméticos/química , Grafito/química , Elasticidad , Conductividad Eléctrica , Fenómenos Mecánicos , Microscopía Electrónica de Transmisión , Estructura Molecular , Nanoestructuras/química , Nanoestructuras/ultraestructura
4.
Mol Cancer Ther ; 11(8): 1758-69, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22848094

RESUMEN

There is a critical need for efficacious therapeutic strategies to improve the outcome of patients afflicted by malignant peripheral nerve sheath tumors (MPNST). Multiple lines of evidence suggest a role for deregulated phosphoinositide 3-kinase (PI3K)/mTOR signaling in MPNST, making this axis an attractive target for therapeutic manipulation. On the basis of previous observations obtained from in vitro experimentation, here we aimed to assess the effects of PI3K/mTOR blockade on MPNST growth in vivo. The anti-MPNST impact of XL765, a dual PI3K/mTOR inhibitor currently being evaluated in human cancer clinical trials, was tested in two human MPNST xenograft models (STS26T and MPNST724) and an experimental model of pulmonary metastasis (STS26T). XL765 abrogated human MPNST local and metastatic growth in severe combined immunodeficient mice. Notably, this therapeutic approach failed to induce apoptosis in MPNST cells but rather resulted in marked productive autophagy. Importantly, genetic and pharmacologic autophagy blockade reversed apoptotic resistance and resulted in significant PI3K/mTOR inhibition-induced MPNST cell death. The addition of the autophagy inhibitor, chloroquine, to the therapeutic regimen of MPNST xenografts after pretreatment with XL765 resulted in superior antitumor effects as compared with either agent alone. Together, preclinical studies described here expand our previous findings and suggest that PI3K/mTOR inhibition alone and (most importantly) in combination with autophagy blockade may comprise a novel and efficacious therapy for patients harboring MPNST.


Asunto(s)
Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Neoplasias de la Vaina del Nervio/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Quinoxalinas/farmacología , Transducción de Señal/efectos de los fármacos , Sulfonamidas/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidores Enzimáticos/administración & dosificación , Humanos , Ratones , Neoplasias de la Vaina del Nervio/tratamiento farmacológico , Neoplasias de la Vaina del Nervio/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Quinoxalinas/administración & dosificación , Sulfonamidas/administración & dosificación , Serina-Treonina Quinasas TOR/metabolismo , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Lab Invest ; 91(3): 392-403, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21060307

RESUMEN

Therapeutic progress in well-differentiated/dedifferentiated liposarcoma (WDLPS/DDLPS) is hampered by lack of relevant experimental models, thereby limiting comprehensive molecularly based investigations. Our goal is to bridge this experimental gap by establishing and characterizing an in vitro/in vivo model useful for examining WDLPS/DDLPS molecular pathogenesis and also therapeutic screening and testing. WDLPS/DDLPS cells were isolated from freshly resected human surgical specimens and were phenotypically and molecularly characterized. MDM2 amplification was determined via FISH analysis. Adipogenic differentiation was evaluated using Oil Red O staining and western blotting (WB). Tyrosine kinase receptors' (TKRs) expression in pre-adipocytes, adipocytes, WDLPS, and DDLPS cells was determined via western blot analysis. SCID mouse xenograft growth was assessed after subcutaneous and/or intraperitoneal tumor cell injection. There was enhanced proliferation, migration, invasion, survival, and pro-angiogenic capacity in DDLPS cells vs WDLPS cells. DDLPS cells formed tumors in SCID mice whereas WDLPS did not. WDLPS/DDLPS cells, especially those that exhibited baseline PPARγ expression, partially retained terminal adipogenic differentiation capacity. MDM2 amplification was found in all WDLPS/DDLPS cell strains, CDK4 overexpression was observed in LPS cells as compared with normal adipocytes, and enhanced JUN expression and phosphorylation was seen in DDLPS cells as compared with WDLPS cells. The TKRs: MET, AXL, KIT, and IGF-1R were overexpressed in LPS cells vs normal adipocytes and pre-adipocytes. In conclusion, these newly established cellular and xenograft models can facilitate investigation of liposarcomagenesis, dedifferentiation, and tumor progression. Further studies of the molecular deregulations so identified may lead to improved therapeutic strategies for patients afflicted by these unfavorable malignancies.


Asunto(s)
Desdiferenciación Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Liposarcoma/tratamiento farmacológico , Liposarcoma/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Biomarcadores/metabolismo , Línea Celular Tumoral , Células Cultivadas , Inducción Enzimática/efectos de los fármacos , Femenino , Humanos , Liposarcoma/patología , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Terapia Molecular Dirigida , Neovascularización Patológica/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Clin Cancer Res ; 16(9): 2591-604, 2010 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-20406839

RESUMEN

PURPOSE: Novel therapeutic approaches for complex karyotype soft tissue sarcoma (STS) are crucially needed. Consequently, we assessed the efficacy of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), in combination with chemotherapy, on local and metastatic growth of human STS xenografts in vivo. EXPERIMENTAL DESIGN: TRAIL was evaluated alone and combined with low-dose doxorubicin in two human STS severe combined immunodeficient mouse xenograft models using fibrosarcoma (HT1080; wild-type p53) and leiomyosarcoma (SKLMS1; mutated p53), testing for effects on local growth, metastasis, and overall survival. Magnetic resonance imaging was used to evaluate local growth and bioluminescence was used to longitudinally assess lung metastases. Tissues were evaluated through immunohistocemistry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining for treatment effects on tumor cell proliferation, apoptosis, angiogenesis, angiogenic factors, and TRAIL receptor expression. Quantitative real-time polymerase chain reaction (QRTPCR) angiogenesis array was used to assess therapy-induced gene expression changes. RESULTS: TRAIL/doxorubicin combination induced marked STS local and metastatic growth inhibition in a p53-independent manner. Significantly increased (P < 0.001) host survival was also demonstrable. Combined therapy induced significant apoptosis, decreased tumor cell proliferation, and increased TRAIL receptor (DR4 and DR5) expression in all treated tumors. Moreover, decreased microvessel density was observed, possibly secondary to increased expression of the antiangiogenic factor CXCL10 and decreased proangiogenic interleukin-8 cytokine in response to TRAIL/doxorubicin combination, as was also observed in vitro. CONCLUSIONS: Given the urgent need for better systemic approaches to STS, clinical trials evaluating TRAIL in combination with low-dose chemotherapy are potentially warranted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Neovascularización Patológica/prevención & control , Sarcoma/tratamiento farmacológico , Animales , Línea Celular Tumoral , Quimiocina CXCL10/genética , Quimiocina CXCL10/metabolismo , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Estimación de Kaplan-Meier , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Ratones , Ratones SCID , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/genética , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sarcoma/genética , Sarcoma/patología , Ligando Inductor de Apoptosis Relacionado con TNF/administración & dosificación , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
7.
PLoS One ; 5(4): e10105, 2010 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-20419128

RESUMEN

BACKGROUND: Vimentin is a ubiquitous mesenchymal intermediate filament supporting mechano-structural integrity of quiescent cells while participating in adhesion, migration, survival, and cell signaling processes via dynamic assembly/disassembly in activated cells. Soft tissue sarcomas and some epithelial cancers exhibiting "epithelial to mesenchymal transition" phenotypes express vimentin. Withaferin-A, a naturally derived bioactive compound, may molecularly target vimentin, so we sought to evaluate its effects on tumor growth in vitro and in vivo thereby elucidating the role of vimentin in drug-induced responses. METHODS AND FINDINGS: Withaferin-A elicited marked apoptosis and vimentin cleavage in vimentin-expressing tumor cells but significantly less in normal mesenchymal cells. This proapoptotic response was abrogated after vimentin knockdown or by blockade of caspase-induced vimentin degradation via caspase inhibitors or overexpression of mutated caspase-resistant vimentin. Pronounced anti-angiogenic effects of Withaferin-A were demonstrated, with only minimal effects seen in non-proliferating endothelial cells. Moreover, Withaferin-A significantly blocked soft tissue sarcoma growth, local recurrence, and metastasis in a panel of soft tissue sarcoma xenograft experiments. Apoptosis, decreased angiogenesis, and vimentin degradation were all seen in Withaferin-A treated specimens. CONCLUSIONS: In light of these findings, evaluation of Withaferin-A, its analogs, or other anti-vimentin therapeutic approaches in soft tissue sarcoma and "epithelial to mesenchymal transition" clinical contexts is warranted.


Asunto(s)
Sarcoma/tratamiento farmacológico , Vimentina/antagonistas & inhibidores , Witanólidos/farmacología , Inhibidores de la Angiogénesis , Animales , Antineoplásicos , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Madre Mesenquimatosas , Ratones , Neovascularización Patológica/tratamiento farmacológico , Sarcoma/patología , Vimentina/metabolismo , Witanólidos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
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