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BACKGROUND: Clear cell Renal Cell Carcinoma (ccRCC) is the frequently diagnosed histological life-threatening tumor subtype in the urinary system. Integrating multi-omics data is emerging as a tool to provide a comprehensive view of biology and disease for better therapeutic interventions. METHOD: We have integrated freely available ccRCC data sets of genome-wide DNA methylome, transcriptome, and active histone modification marks, H3K27ac, H3K4me1, and H3K4me3 specific ChIP-seq data to screen genes with higher expression. Further, these genes were filtered based on their effect on survival upon alteration in expression. RESULTS: The six multi-omics-based identified genes, RUNX1, MSC, ADA, TREML1, TGFA, and VWF, showed higher expression with enrichment of active histone marks and hypomethylated CpG in ccRCC. In continuation, the identified genes were validated by an independent dataset and showed a correlation with nodal and metastatic status. Furthermore, gene ontology and pathway analysis revealed that immune-related pathways are activated in ccRCC patients. CONCLUSIONS: The network analysis of six overexpressed genes suggests their potential role in an immunosuppressive environment, leading to tumor progression and poor prognosis. Our study shows that the multi-omics approach helps unravel complex biology for patient subtyping and proposes combination strategies with epi-drugs for more precise immunotherapy in ccRCC.
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Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Neoplasias Renales/genética , Neoplasias Renales/patología , Epigenoma , Perfilación de la Expresión Génica , Transcriptoma/genética , Microambiente Tumoral/genética , Receptores Inmunológicos/genéticaRESUMEN
The topological ferromagnet CoS2 exhibits an anhysteretic, weakly first-order transition at the Curie temperature of 119.8 K with a tricritical point µ0Htcp at 0.034 T. Magnetic symmetry and the mixing of majority and minority spin eg bands at a subband crossing just above the Fermi level produce a topological component of the magnetization that leads to a negative M3 term in the Landau free energy. The position of the Fermi level relative to the subband crossing is critical for controlling the order of the transition. Hole doping in Co0.89Fe0.11S2 drains the minority-spin eg pocket and results in a normal second-order phase transition. Electron doping in Co0.94Ni0.06S2 raises the Fermi level toward the subband gap, producing a strongly first-order transition with 15 K hysteresis. Our results demonstrate a relation between topological electronic structure and thermal hysteresis at the Curie point, which may help in the search for magnetocaloric materials.
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Understanding memory requires an explanation for how information can be stored in the brain in a stable state. The change in the brain that accounts for a given memory is referred to as an engram. In recent years, the term engram has been operationalized as the cells that are activated by a learning experience, undergoes plasticity, and are sufficient and necessary for memory recall. Using this framework, and a growing toolbox of related experimental techniques, engram manipulation has become a central topic in behavioral, systems, and molecular neuroscience. Recent research on the topic has provided novel insights into the mechanisms of long-term memory storage, and its overlap with instinct. We propose that memory and instinct may be embodied as isomorphic topological structures within the brain's microanatomical circuitry.
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Aprendizaje , Memoria , Encéfalo , Almacenamiento y Recuperación de la InformaciónRESUMEN
Calcium Homeostasis is a complex physiological process. Its mathematical model results in high order differential equation. In this paper, a model order reduction technique, based on time scale separation is proposed for a 27th order Calcium Homeostasis and Bone Remodeling (CHBR) system. The original state-space model after linearization has been decoupled into three reduced order subsystems: "Very-Slow", "Slow" and "Fast", at the same time preserving the structure of the system. The time and frequency response of individual reduced order model has been compared with the response of the original system. Furthermore, the effect of administering a therapeutic daily moderate dose of PTH has been studied with the help of reduced order models.
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Remodelación Ósea/fisiología , Calcio/fisiología , Homeostasis/fisiología , Modelos Biológicos , Calcio/metabolismo , HumanosRESUMEN
RATIONALE: Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma with a dismal outcome. Most patients relapse in intracranial sites and <5% of patients relapse in extracranial sites. Here, we present the first case of PCNSL with an adrenal relapse. PATIENT CONCERNS: A 72-year-old woman, first presented 7 years ago with complaints of headache and dizziness. DIAGNOSES: Enhanced magnetic resonance imaging revealed the mass within the splenium of the corpus callosum. On histological examination, there was a diffuse growth pattern of neoplastic cells in the brain biopsy. Immunohistochemistry and flow cytometric analysis demonstrated that the neoplastic cells were of B-cell lineage. INTERVENTIONS: The patient underwent methotrexate-based chemotherapy and whole-brain radiotherapy after the initial diagnosis of primary central nervous system-large B-cell lymphoma (CNS-DLBCL). OUTCOMES: After 4 years of clinical remission, the patient was diagnosed with endometrial cancer. Interestingly, a radiological study following the treatment of endometrial cancer demonstrated a right adrenal mass, which was suspicious for malignancy. Morphologic examination and immunohistochemistry studies confirmed the diagnosis of diffuse large B-cell lymphoma. A fluorescent in situ hybridization panel for lymphoma showed rearrangement of Immunoglobulin heavy chain (IGH) and B-cell lymphoma 6 (BCL6), respectively, suggesting fusion of BCL6/IGH. Immunoglobulin kappa analysis demonstrated a common origin for the brain and adrenal lesions, which led to the final diagnosis of an adrenal relapse of CNS-DLBCL. LESSONS: PCNSL is a highly infiltrative neoplasm, particularly at relapse. To the best of our knowledge, this is the first case of CNS-DLBCL with adrenal relapse. Considering the poor outcome of CNS-DLBCL, molecular genetic studies should be done to identify a common origin for the primary and secondary lesion.
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Neoplasias de las Glándulas Suprarrenales/secundario , Neoplasias del Sistema Nervioso Central/patología , Linfoma de Células B Grandes Difuso/patología , Recurrencia Local de Neoplasia/patología , Anciano , Femenino , HumanosRESUMEN
BACKGROUND: Adoptive cell transfer (ACT) is a promising cancer immunotherapeutic strategy that remains ineffective for a large subset of patients. ACT with memory CD8+ T cells (Tmem) has been shown to have superior efficacy compared to traditional ACT with effector CD8+ T cells (Teff). Teff and Tmem have complementary physiological advantages for immunotherapy, but previous publications have not examined ACT using a combination of Teff and Tmem. METHODS: Splenocytes harvested from Ly5.1+/C57BL/6 mice during and after infection with lymphocytic choriomeningitis virus (LCMV) were used to generate bona fide effector and memory CD8+ T cells specific for the LCMV epitope peptide GP33. Congenic Ly5.2+/C57BL/6 mice were inoculated with B16F10 melanoma cells transfected to express very low levels of GP33, then treated with ACT 7 days later with GP33-specific Teff, Tmem, or a combination of Teff + Tmem. RESULTS: Inhibition of melanoma growth was strongest in mice receiving combinatorial ACT. Although combinatorial ACT and memory ACT resulted in maximal intratumoral infiltration of CD8+ T cells, combinatorial ACT induced stronger infiltration of endogenous CD8+ T cells than Tmem ACT and a stronger systemic T cell responsiveness to tumor antigen. In vitro assays revealed rapid but transient melanoma inhibition with Teff and gradual but prolonged melanoma inhibition with Tmem; the addition of Tmem enhanced the ability of Teff to inhibit melanoma in a manner that could be reproduced using conditioned media from activated Tmem and blocked by the addition of anti-IL-2 blocking antibody. CONCLUSIONS: These findings suggest that a novel combinatorial approach that takes advantage of the unique and complementary strengths of tumor-specific Teff and Tmem may be a way to optimize the efficacy of adoptive immunotherapy.
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Traslado Adoptivo/métodos , Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica/inmunología , Inmunoterapia/métodos , Melanoma/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , RatonesRESUMEN
Adoptive cell transfer (ACT) melanoma immunotherapy typically employs acutely activated effector CD8+ T cells for their ability to rapidly recognize and clear antigen. We have previously observed that effector CD8+ T cells are highly susceptible to melanoma-induced suppression, whereas memory CD8+ T cells are not. Although memory T cells have been presumed to be potentially advantageous for ACT, the kinetics of local and systemic T cell responses after effector and memory ACT have not been compared. B16F10 melanoma cells stably transfected to express very low levels of the lymphocytic choriomeningitis virus (LCMV) peptide GP33 (B16GP33) were inoculated into syngeneic C57BL/6 mice. Equal numbers of bona fide naïve, effector, or memory phenotype GP33-specific CD8+ T cells were adoptively transferred into mice 1 day after B16GP33 inoculation. The efficacy of ACT immunotherapy was kinetically assessed using serial tumor measurements and flow cytometric analyses of local and systemic CD8+ T cell responses. Control of B16GP33 tumor growth, persistence of adoptively transferred CD8+ cells, intratumoral infiltration of CD8+ T cells, and systemic CD8+ T cell responsiveness to GP33 were strongest after ACT of memory CD8+ T cells. Following surgical tumor resection and melanoma tumor challenge, only mice receiving memory T cell-based ACT immunotherapy exhibited durable tumor-specific immunity. These findings demonstrate how the use of non-expanded memory CD8+ T cells may enhance ACT immunotherapeutic efficacy.
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Linfocitos T CD8-positivos/inmunología , Inmunoterapia Adoptiva/métodos , Melanoma Experimental/inmunología , Melanoma Experimental/terapia , Linfocitos T/trasplante , Animales , Antígenos Virales/genética , Antígenos Virales/inmunología , Antígenos Virales/metabolismo , Linfocitos T CD8-positivos/metabolismo , Línea Celular Tumoral , Supervivencia Celular/genética , Supervivencia Celular/inmunología , Femenino , Citometría de Flujo , Glicoproteínas/genética , Glicoproteínas/inmunología , Glicoproteínas/metabolismo , Memoria Inmunológica/inmunología , Melanoma Experimental/genética , Ratones Endogámicos C57BL , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Carga Tumoral/genética , Carga Tumoral/inmunología , Proteínas Virales/genética , Proteínas Virales/inmunología , Proteínas Virales/metabolismoRESUMEN
Acute myeloid leukemia (AML) is a heterogeneous and fatal disease with an urgent need for improved therapeutic regimens given that most patients die from relapsed disease. Irrespective of mutation status, the development of aggressive leukemias is enabled by increasing dependence on signaling networks. We demonstrate that a hyperactive signalosome drives addiction of AML cells to a tumor-specific Hsp90 species (teHsp90). Through genetic, environmental, and pharmacologic perturbations, we demonstrate a direct and quantitative link between hyperactivated signaling pathways and apoptotic sensitivity of AML to teHsp90 inhibition. Specifically, we find that hyperactive JAK-STAT and PI3K-AKT signaling networks are maintained by teHsp90 and, in fact, gradual activation of these networks drives tumors increasingly dependent on teHsp90. Thus, although clinically aggressive AML survives via signalosome activation, this addiction creates a vulnerability that can be exploited with Hsp90-directed therapy.
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Proteínas HSP90 de Choque Térmico/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Transducción de Señal/fisiología , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Benzodioxoles/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Ratones , Ratones Desnudos , Purinas/farmacología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Acute myeloid leukemia (AML) is the most common form of adult leukemia. The transcription factor fusion CBFß-SMMHC (core binding factor ß and the smooth-muscle myosin heavy chain), expressed in AML with the chromosome inversion inv(16)(p13q22), outcompetes wild-type CBFß for binding to the transcription factor RUNX1, deregulates RUNX1 activity in hematopoiesis, and induces AML. Current inv(16) AML treatment with nonselective cytotoxic chemotherapy results in a good initial response but limited long-term survival. Here, we report the development of a protein-protein interaction inhibitor, AI-10-49, that selectively binds to CBFß-SMMHC and disrupts its binding to RUNX1. AI-10-49 restores RUNX1 transcriptional activity, displays favorable pharmacokinetics, and delays leukemia progression in mice. Treatment of primary inv(16) AML patient blasts with AI-10-49 triggers selective cell death. These data suggest that direct inhibition of the oncogenic CBFß-SMMHC fusion protein may be an effective therapeutic approach for inv(16) AML, and they provide support for transcription factor targeted therapy in other cancers.
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Antineoplásicos/uso terapéutico , Bencimidazoles/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Proteínas de Fusión Oncogénica/antagonistas & inhibidores , Animales , Antineoplásicos/química , Bencimidazoles/química , Línea Celular Tumoral , Subunidad alfa 2 del Factor de Unión al Sitio Principal/antagonistas & inhibidores , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Proteínas de Fusión Oncogénica/metabolismo , Mapas de Interacción de Proteínas , Bibliotecas de Moléculas Pequeñas/químicaRESUMEN
Immunotherapeutic approaches to the treatment of advanced melanoma have relied on strategies that augment the responsiveness of endogenous tumor-specific T-cell populations [eg, cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) blockade-mediated checkpoint inhibition] or introduce exogenously prepared tumor-specific T-cell populations [eg, adoptive cell transfer (ACT)]. Although both approaches have shown considerable promise, response rates to these therapies remain suboptimal. We hypothesized that a combinatorial approach to immunotherapy using both CTLA-4 blockade and nonlymphodepletional ACT could offer additive therapeutic benefit. C57BL/6 mice were inoculated with syngeneic B16F10 melanoma tumors transfected to express low levels of the lymphocytic choriomeningitis virus peptide GP33 (B16GP33), and treated with no immunotherapy, CTLA-4 blockade, ACT, or combination immunotherapy of CTLA-4 blockade with ACT. Combination immunotherapy resulted in optimal control of B16GP33 melanoma tumors. Combination immunotherapy promoted a stronger local immune response reflected by enhanced tumor-infiltrating lymphocyte populations, and a stronger systemic immune responses reflected by more potent tumor antigen-specific T-cell activity in splenocytes. In addition, whereas both CTLA-4 blockade and combination immunotherapy were able to promote long-term immunity against B16GP33 tumors, only combination immunotherapy was capable of promoting immunity against parental B16F10 tumors as well. Our findings suggest that a combinatorial approach using CTLA-4 blockade with nonlymphodepletional ACT may promote additive endogenous and exogenous T-cell activities that enable greater therapeutic efficacy in the treatment of melanoma.
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Anticuerpos Monoclonales/administración & dosificación , Antígeno CTLA-4/antagonistas & inhibidores , Inmunoterapia Adoptiva , Linfocitos Infiltrantes de Tumor/inmunología , Melanoma Experimental/inmunología , Neoplasias Cutáneas/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Antígenos Virales/genética , Antígenos Virales/metabolismo , Antígeno CTLA-4/inmunología , Terapia Combinada , Modelos Animales de Enfermedad , Femenino , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Inmunidad Celular , Inmunidad Humoral , Melanoma Experimental/genética , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Neoplasias Cutáneas/genética , Transgenes/genética , Carga Tumoral , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
OBJECTIVE: To assess the feasibility and effectiveness of pulse-oximetry as a screening tool in the detection of critical congenital heart disease (CCHD) in newborns. METHODS: Post-natal babies born between 01/01/2007-31/12/2009 were eligible. Post-ductal pulse-oximetry was performed using Nellcor® NPB 40 pulse oximeter with reusable OXI-A/N saturation probe. Saturations ≥95% were deemed normal. If saturations were <95%, an echocardiogram was done. The regional paediatric cardiology database and death records identified babies later diagnosed with CCHD. RESULTS: 6329/9613 eligible babies were studied and pulse-oximetry was performed at a mean age of 28 hours (range 6-72 hours). Fourteen babies had saturations <95%. CCHD was diagnosed in 7/14 babies; 4/7 had no clinical signs. Of the remaining 7 babies, 3 had non-critical but significant CHD and 4 had an undiagnosed respiratory illness or sepsis. All babies with low saturations had identifiable pathologies. One baby with normal saturations was later diagnosed with transposition of the great arteries. The sensitivity and specificity of identifying an unwell baby was 93.3% and 100% respectively; the sensitivity and specificity of identifying CCHD was 87.5% and 99.8% respectively. Clinical examination alone would have missed 4/7 (57%) of these. CONCLUSION: Pulse-oximetry is safe, acceptable, non-invasive and effective. Our study supports the routine use of pulse oximetry as part of the newborn check.
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Cardiopatías Congénitas/diagnóstico , Tamizaje Neonatal/métodos , Oximetría , Enfermedades Asintomáticas , Estudios de Factibilidad , Femenino , Humanos , Recién Nacido , Masculino , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
The mechanism of protein folding during early stages of the process has three determinants. First, moving water molecules obey the rules of low Reynolds number physics without an inertial component. Molecular movement is instantaneous and size insensitive. Proteins emerging from the ribosome move and rotate without an external force if they change shape, forming and propagating helical structures that increases translocational efficiency. Forward motion ceases when the shape change or propelling force ceases. Second, application of quantum field theory to water structure predicts the spontaneous formation of low density coherent units of fixed size that expel dissolved atmospheric gases. Structured water layers with both coherent and non-coherent domains, form a sheath around the new protein. The surface of exposed hydrophobic amino acids is protected from water contact by small nanobubbles of dissolved atmospheric gases, 5 or 6 molecules on average, that vibrate, attracting even widely separated resonating nanobubbles. This force results from quantum effects, appearing only when the system is within and interacts with an oscillating electromagnetic field. The newly recognized quantum force sharply bends the peptide and is part of a dynamic field determining the pathway of protein folding. Third, the force initiating the tertiary folding of proteins arises from twists at the position of each hydrophobic amino acid, that minimizes surface exposure of the hydrophobic amino acids and propagates along the protein. When the total bend reaches 360°, the leading segment of water sheath intersects the trailing segment. This steric self-intersection expels water from overlapping segments of the sheath and by Newton׳s second law moves the polypeptide chain in an opposite direction. Consequently, with very few exceptions that we enumerate and discuss, tertiary structures are absent from proteins without hydrophobic amino acids, which control the early stages of protein folding and the overall shape of protein. Consequently, proteins only adopt a limited number of forms. The formation of quaternary structures is not necessarily prevented by the absence of hydrophobic amino acids.
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Modelos Biológicos , Péptidos/química , Biosíntesis de Proteínas/fisiología , Pliegue de Proteína , Agua/química , Hidrodinámica , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
Ciclopirox, an antifungal agent commonly used for the dermatologic treatment of mycoses, has been shown recently to have antitumor properties. Although the exact mechanism of ciclopirox is unclear, its antitumor activity has been attributed to iron chelation and inhibition of the translation initiation factor eIF5A. In this study, we identify a novel function of ciclopirox in the inhibition of mTOR. As with other mTOR inhibitors, we show that ciclopirox significantly enhances the ability of the established preclinical antileukemia compound, parthenolide, to target acute myeloid leukemia. The combination of parthenolide and ciclopirox demonstrates greater toxicity against acute myeloid leukemia than treatment with either compound alone. We also demonstrate that the ability of ciclopirox to inhibit mTOR is specific to ciclopirox because neither iron chelators nor other eIF5A inhibitors affect mTOR activity, even at high doses. We have thus identified a novel function of ciclopirox that might be important for its antileukemic activity.
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Antiinflamatorios no Esteroideos/farmacología , Antifúngicos/farmacología , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/enzimología , Piridonas/farmacología , Sesquiterpenos/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Antiinflamatorios no Esteroideos/agonistas , Antifúngicos/agonistas , Línea Celular Tumoral , Ciclopirox , Sinergismo Farmacológico , Femenino , Humanos , Leucemia Mieloide Aguda/patología , Masculino , Piridonas/agonistas , Sesquiterpenos/agonistas , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Fluorescent ligands for the heat shock protein 90 (Hsp90) were synthesized containing either fluorescein isothiocyanate (FITC), 4-nitrobenzo[1,2,5]oxadiazole (NBD) or the red shifted dye sulforhodamine 101 (Texas Red) conjugated to PU-H71. Two of the compounds, PU-H71-FITC2 (9) and PU-H71-NBD1 (8), were shown to be suitable for fluorescence-activated flow cytometry and fluorescence microscopy. Thus these molecules serve as useful probes for studying Hsp90 in heterogeneous live cell populations.
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Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Proteínas HSP90 de Choque Térmico/análisis , Purinas/química , Línea Celular Tumoral , Técnicas de Química Sintética , Citometría de Flujo , Humanos , Microscopía Fluorescente , Estructura Molecular , EstereoisomerismoRESUMEN
We have previously shown that the plant-derived compound parthenolide (PTL) can impair the survival and leukemogenic activity of primary human acute myeloid leukemia (AML) stem cells. However, despite the activity of this agent, PTL also induces cellular protective responses that likely function to reduce its overall cytotoxicity. Thus, we sought to identify pharmacologic agents that enhance the antileukemic potential of PTL. Toward this goal, we used the gene expression signature of PTL to identify compounds that inhibit cytoprotective responses by performing chemical genomic screening of the Connectivity Map database. This screen identified compounds acting along the phosphatidylinositol 3-kinase and mammalian target of rapamycin pathways. Compared with single agent treatment, exposure of AML cells to the combination of PTL and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitors significantly decreased viability of AML cells and reduced tumor burden in vitro and in murine xenotransplantation models. Taken together, our data show that rational drug combinations can be identified using chemical genomic screening strategies and that inhibition of cytoprotective functions can enhance the eradication of primary human AML cells.
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Inhibidores Enzimáticos/farmacología , Perfilación de la Expresión Génica , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Sesquiterpenos/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Médula Ósea/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Sinergismo Farmacológico , Citometría de Flujo , Humanos , Leucemia Mieloide Aguda/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sirolimus/análogos & derivados , Sirolimus/farmacologíaRESUMEN
BACKGROUND: The mammalian protein kinase TLK1 is a homologue of Tousled, a gene involved in flower development in Arabidopsis thaliana. The function of TLK1 is not well known, although knockout of the gene in Drosophila, or expression of a dominant negative mutant in mouse mammary cells causes loss of nuclear divisions and chromosome mis-segregation. TLK1B is a splice variant of TLK1 and it confers radioresistance in a normal mammary mouse cell line possibly due to increased chromatin remodeling capacity, but the mechanism of resistance remains to be fully elucidated. RESULTS: We now show that TLK1B also affords protection against UV radiation. We find that nuclear extracts isolated from TLK1B-containing mouse cells promote more efficient chromatin assembly than comparable extracts lacking TLK1B. TLK1B-containing extracts are also more efficient in repair of UV-damaged plasmid DNA assembled into nucleosomes. One of the two known substrates of TLK1 (or TLK1B) is the histone chaperone Asf1, and immuno-inactivation experiments suggest that TLK1B increases UV-repair through the action of Asf1 on chromatin assembly/disassembly. CONCLUSION: Our studies provide evidence for TLK1B-mediated phosphorylation of Asf1 triggering DNA repair. We suggest that this occurs via Asf1-mediated chromatin assembly at the sites of UV damage.
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Proteínas de Ciclo Celular/metabolismo , Ensamble y Desensamble de Cromatina/fisiología , Reparación del ADN/fisiología , ADN/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Western Blotting , Línea Celular , Ensamble y Desensamble de Cromatina/genética , ADN/genética , ADN/efectos de la radiación , Daño del ADN , Células HeLa , Histonas/metabolismo , Humanos , Chaperonas Moleculares , Mutación/genética , Nucleosomas/genética , Nucleosomas/metabolismo , Fosforilación , Plásmidos/genética , Plásmidos/metabolismo , Plásmidos/efectos de la radiación , Proteínas Serina-Treonina Quinasas/genética , Rayos UltravioletaRESUMEN
A novel image-based defect identification and coding technique has been proposed for fluted ingots, which are used for the production of locomotive wheels. The edge density map has been used for defect identification and an object-based coding approach has been applied for the storage of defective ingots. The complete scheme has been implemented in one of the integrated steel plants of India.
RESUMEN
BACKGROUND: The mammalian protein kinase TLK1 is a homologue of Tousled, a gene involved in flower development in Arabidopsis thaliana. The function of TLK1 is not well known, although knockout of the gene in Drosophila or expression of a dominant negative mutant in mouse cells causes loss of nuclear divisions and missegregation of chromosomes probably, due to alterations in chromatin remodeling capacity. Overexpression of TLK1B, a spliced variant of the TLK1 mRNA, in a model mouse cell line increases it's resistance to ionizing radiation (IR) or the radiomimetic drug doxorubicin, also likely due to changes in chromatin remodeling. TLK1B is translationally regulated by the availability of the translation factor eIF4E, and its synthesis is activated by IR. The reason for this mechanism of regulation is likely to provide a rapid means of promoting repair of DSBs. TLK1B specifically phosphorylates histone H3 and Asf1, likely resulting in changes in chromatin structure, particularly at double strand breaks (DSB) sites. RESULTS: In this work, we provide several lines of evidence that TLK1B protects the cells from IR by facilitating the repair of DSBs. First, the pattern of phosphorylation and dephosphorylation of H2AX and H3 indicated that cells overexpressing TLK1B return to pre-IR steady state much more rapidly than controls. Second, the repair of episomes damaged with DSBs was much more rapid in cells overexpressing TLK1B. This was also true for repair of genomic damage. Lastly, we demonstrate with an in vitro repair system that the addition of recombinant TLK1B promotes repair of a linearized plasmid incubated with nuclear extract. In addition, TLK1B in this in vitro system promotes the assembly of chromatin as shown by the formation of more highly supercoiled topomers of the plasmid. CONCLUSION: In this work, we provide evidence that TLK1B promotes the repair of DSBs, likely as a consequence of a change in chromatin remodeling capacity that must precede the assembly of repair complexes at the sites of damage.
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Reparación del ADN , Proteínas Serina-Treonina Quinasas/fisiología , Tolerancia a Radiación , Animales , Línea Celular , Ensamble y Desensamble de Cromatina , Daño del ADN , Histonas/metabolismo , Humanos , Fosforilación , Plásmidos , Proteínas Serina-Treonina Quinasas/genética , Radiación Ionizante , TransfecciónRESUMEN
This paper describes a unique single camera-based dimension storage method for image-based measurement. The system has been designed and implemented in one of the integrated steel plants of India. The purpose of the system is to encode the frontal cross-sectional area of an ingot. The encoded data will be stored in a database to facilitate the future manufacturing diagnostic process. The compression efficiency and reconstruction error of the lossy encoding technique have been reported and found to be quite encouraging.
Asunto(s)
Algoritmos , Inteligencia Artificial , Análisis de Falla de Equipo/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Mantenimiento/métodos , Reconocimiento de Normas Patrones Automatizadas , Grabación en Video/métodosRESUMEN
INTRODUCTION: The overexpression of eukaryotic initiation factor 4E (eIF4E), a critical component of the "RNA helicase" necessary for the initiation of protein synthesis of mRNAs with long 5' prime untranslated regions (5'UTRs), can result in malignant transformation. In a prospective study on breast cancer outcome of women with stage I to III disease, eIF4E overexpression was an independent predictor of cancer recurrence (RR = 7.3, CI = 1.58-33.9). Dysregulation of Tousled-like kinase 1B (TLK1B), a threonine kinase with a highly conserved gene sequence, has been linked to defects in cell division and DNA replication. In cell lines, TLK1B overexpression has been recently associated with resistance to radiation. The 5'UTR of TLK1B is long (1088 nt) and the structure is complex. Our hypothesis is that TLK1B elevation is correlated with the overexpression of eIF4E in human breast carcinoma. MATERIAL AND METHODS: Eighty-seven patients with invasive breast cancer and 11 patients with benign breast disease were accrued prospectively. Clinical data collected include age, race, stage, grade of tumor, ER, and PR status. TLK1B and eIF4E levels were quantified by Western blot analysis. Statistical analysis was performed using Spearman correlation, paired and unpaired t test, and multivariate analysis. RESULTS: In the 87 cancer specimens from patients with breast carcinoma, eIF4E level was elevated by a mean of 9.5-fold (range = 1.8-48.4), and TLK1B was elevated by a mean of 9.4-fold (range = 1.0-58.0) when compared to the 11 specimens from noncancer patients. Multivariate analysis performed demonstrates the degree of eIF4E overexpression is independent of age, race, tumor grade, and ER or PR status of the tumor. Similarly, the degree of TLK1B elevation is independent of age, tumor grade, and ER or PR status of the tumor. Using the Spearman correlation, the degree of TLK1B elevation was strongly correlated with the degree of eIF4E overexpression (r = 0.39, P = 0.001). CONCLUSIONS: Both eIF4E and TLK1B are elevated in breast cancer specimens but not in benign breast specimens from noncancer patients. The degree of TLK1B elevation is correlated with the degree of IF4E overexpression. Both eIF4E and TLK1B overexpression are independent of tumor grade, tumor stage, and ER and PR status.