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1.
J Clin Med ; 13(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38731055

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-33048742

ABSTRACT

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.


Subject(s)
Computer Graphics , Neural Networks, Computer , Algorithms , Photic Stimulation
3.
Nat Commun ; 3: 1241, 2012.
Article in English | MEDLINE | ID: mdl-23212370

ABSTRACT

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.


Subject(s)
Biomimetic Materials/chemistry , Graphite/chemistry , Elasticity , Electric Conductivity , Mechanical Phenomena , Microscopy, Electron, Transmission , Molecular Structure , Nanostructures/chemistry , Nanostructures/ultrastructure
4.
Mol Cancer Ther ; 11(8): 1758-69, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22848094

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/pharmacology , Autophagy/drug effects , Enzyme Inhibitors/pharmacology , Nerve Sheath Neoplasms/metabolism , Phosphoinositide-3 Kinase Inhibitors , Quinoxalines/pharmacology , Signal Transduction/drug effects , Sulfonamides/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors , Animals , Antineoplastic Agents/administration & dosage , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Enzyme Inhibitors/administration & dosage , Humans , Mice , Nerve Sheath Neoplasms/drug therapy , Nerve Sheath Neoplasms/pathology , Phosphatidylinositol 3-Kinases/metabolism , Quinoxalines/administration & dosage , Sulfonamides/administration & dosage , TOR Serine-Threonine Kinases/metabolism , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
5.
Lab Invest ; 91(3): 392-403, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21060307

ABSTRACT

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.


Subject(s)
Cell Dedifferentiation/drug effects , Cell Differentiation/drug effects , Drug Screening Assays, Antitumor/methods , Liposarcoma/drug therapy , Liposarcoma/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Adult , Aged , Aged, 80 and over , Animals , Biomarkers/metabolism , Cell Line, Tumor , Cells, Cultured , Enzyme Induction/drug effects , Female , Humans , Liposarcoma/pathology , Male , Mice , Mice, SCID , Middle Aged , Molecular Targeted Therapy , Neovascularization, Pathologic/drug therapy , Proto-Oncogene Proteins c-mdm2/genetics , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
6.
PLoS One ; 5(4): e10105, 2010 Apr 16.
Article in English | MEDLINE | ID: mdl-20419128

ABSTRACT

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.


Subject(s)
Sarcoma/drug therapy , Vimentin/antagonists & inhibitors , Withanolides/pharmacology , Angiogenesis Inhibitors , Animals , Antineoplastic Agents , Apoptosis/drug effects , Cell Proliferation/drug effects , Mesenchymal Stem Cells , Mice , Neovascularization, Pathologic/drug therapy , Sarcoma/pathology , Vimentin/metabolism , Withanolides/therapeutic use , Xenograft Model Antitumor Assays
7.
Clin Cancer Res ; 16(9): 2591-604, 2010 May 01.
Article in English | MEDLINE | ID: mdl-20406839

ABSTRACT

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.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Apoptosis/drug effects , Neovascularization, Pathologic/prevention & control , Sarcoma/drug therapy , Animals , Cell Line, Tumor , Chemokine CXCL10/genetics , Chemokine CXCL10/metabolism , Doxorubicin/administration & dosage , Doxorubicin/pharmacology , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Humans , Immunohistochemistry , In Situ Nick-End Labeling , Kaplan-Meier Estimate , Lung Neoplasms/prevention & control , Lung Neoplasms/secondary , Mice , Mice, SCID , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Oligonucleotide Array Sequence Analysis , Platelet Endothelial Cell Adhesion Molecule-1/analysis , Receptors, TNF-Related Apoptosis-Inducing Ligand/genetics , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sarcoma/genetics , Sarcoma/pathology , TNF-Related Apoptosis-Inducing Ligand/administration & dosage , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays
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