While mid-infrared optical frequency combs have been widely utilized in areas such as trace gas sensing, chemical kinetics, and combustion science, their relatively low power has limited sensitivities and led to correspondingly long acquisition times. We have developed a new approach in which an electro-optic frequency comb is utilized to pump a continuous-wave singly-resonant optical parametric oscillator in order to spectrally translate the comb into the mid-infrared (2.19 µm and 4.
View Article and Find Full Text PDFDaily life requires transitions between performance of well-practiced, automatized behaviors reliant upon internalized representations and behaviors requiring external focus. Such transitions involve differential activation of the default mode network (DMN), a group of brain areas associated with inward focus. We asked how optogenetic modulation of the ventral pallidum (VP), a subcortical DMN node, impacts task switching between internally to externally guided lever-pressing behavior in the rat.
View Article and Find Full Text PDFWe report on the design and automation of a mid-infrared, continuous wave, singly-resonant optical parametric oscillator. Hands-free controls and the implementation of a tuning algorithm allowed for hundreds of nanometers of continuous, effective-mode-hop-free tuning over the range of 2190-4000 nm. To demonstrate the applicability of this light source and algorithm to mid-IR spectroscopy, we performed a sample spectroscopy measurement in a CH gas cell and compared the experimentally-measured absorption spectrum to HITRAN 2016 simulations.
View Article and Find Full Text PDFQigong is an ancient form of health maintenance, which is part of Traditional China Medicine. Numerous beneficial mental and physical effects have been classically ascribed to this traditional psychosomatic method. The purpose of this work has been to assess the effects of Taoist qigong practice on several hormonal parameters of the Hipotalamic-Pituitary-Adrenal axis and specific measures of psychological well-being in healthy subjects.
View Article and Find Full Text PDFBackground: In haploidentical stem cell transplantation (SCT), the "ideal donor" selection is not performed in a standardized way according to killer cell immunoglobulin-like receptor (KIR) genotype expressed by potential donors. The aim of this study was to evaluate the relevance of KIR genotype in a series of patients submitted to haploidentical SCT in our center.
Methods: We retrospectively analyzed 30 patients that were prepared with the use of a conditioning regimen including thiotepa-busulfan-fludarabine with high doses of post-transplantation cyclophosphamide (CyPT) and tacrolimus as graft-versus-host disease (GVHD) prophylaxis.
Photonic crystal microcavity biosensors can detect single biomolecules, but reliance on diffusion from microfluidic flow for particle delivery limits the minimum detectable particle concentration. Here the particle equation of motion is solved to find the sensitivity enhancement due to optical forces. The enhancement is examined for a range of parameters, including input optical power, fluid flow rate, device quality factor, and particle size.
View Article and Find Full Text PDFThe level of BCR-ABL1 reached after treatment with tyrosine kinase inhibitors is an effective marker of the therapeutic response and a good survival predictor in chronic myeloid leukemia (CML) patients. However, no agreement has yet been achieved about either the standardization of the technique to determine BCR-ABL1 or the interpretation of the results. The aim of this study was to compare the method currently recommended by the European Leukemia Net, which includes the application of a conversion factor to express the results in international scale, with an automated method (Xpert BCR-ABL™, Cepheid).
View Article and Find Full Text PDFWhereas transcriptional silencing of genes due to epigenetic mechanisms is one of the most important alterations in acute lymphoblastic leukemia (ALL), some recent studies indicate that DNA methylation contributes to down-regulation of miRNAs during tumorigenesis. To explore the epigenetic alterations of miRNAs in ALL, we analyzed the methylation and chromatin status of the miR-124a loci in ALL. Expression of miR-124a was down-regulated in ALL by hypermethylation of the promoter and histone modifications including decreased levels of 3mk4H3 and AcH3 and increased levels of 2mK9H3, 3mK9H3, and 3mK27H3.
View Article and Find Full Text PDFBackground: Expression of the pro-apoptotic BCL-2-interacting mediator (BIM) has recently been implicated in imatinib-induced apoptosis of BCR-ABL1(+) cells. However, the mechanisms involved in the regulation of BIM in CML and its role in the clinical setting have not been established.
Design And Methods: We analysed the mRNA expression of BIM in 100 newly diagnosed patients with CML in chronic phase by Q-RT-PCR and the protein levels by Western blot analysis.
Purpose: To identify microRNAs (miRNAs) epigenetically regulated in acute lymphoblastic leukemia (ALL).
Methods: We first examined ALL-derived cell lines for the presence of abnormal levels of two different histone modifications (trimethylation of H3 lysine 4 [K4H3me3] and dimethylation of H3 lysine 9 [K9H3me2]) in the 5'UTR regions around CpG islands of 78 miRNAs by chromatin immunoprecipitation (ChIP)-on-ChIP analysis. Methylation status (methylation-specific polymerase chain reaction [PCR]) and expression (quantitative PCR) of miRNAs showing a pattern of histone modifications linked to a closed chromatin structure were analyzed in a panel of six ALL cell lines and in 353 ALL patients.
MicroRNAs (miRNA) are small noncoding, single-stranded RNAs that inhibit gene expression at a posttranscriptional level, whose abnormal expression has been described in different tumors. The aim of our study was to identify miRNAs potentially implicated in chronic myeloid leukemia (CML). We detected an abnormal miRNA expression profile in mononuclear and CD34(+) cells from patients with CML compared with healthy controls.
View Article and Find Full Text PDFThe clinical significance of aberrant promoter methylation of the canonical Wnt pathway antagonist genes (sFRP1, sFRP2, sFRP4, sFRP5, Wif1, Dkk3, and Hdpr1) and also putative tumor-suppressor gene Wnt5a, belonging to the non-canonical Wnt signaling pathway, was investigated in a large series of 75 patients with Philadelphia chromosome-positive acute lymphoblastic leukemia by methylation-specific polymerase chain reaction. At least one methylated gene was observed in cells from 66% (49/75) of patients (methylated group). Disease-free survival and overall survival at 9 years were 51 and 40%, respectively, for the unmethylated group and 3 and 2%, respectively, for the methylated group (both P < 0.
View Article and Find Full Text PDFIn order to determine new signal transduction pathways implicated in chronic myeloid leukaemia (CML), we performed a gene expression profile comparison between CD34+ cells from CML patients and healthy donors. Functional studies were performed using the Mo7e and Mo7e-p210 cell lines. Expression of CCND1 (Cyclin D1), as well as the chaperone HSPA8, which is important for regulation of CCND1, were significantly upregulated in CD34+ CML cells.
View Article and Find Full Text PDFWnt5a is a member of the Wnt family of proteins that signals through the non-canonical Wnt/Ca(2+) pathway to suppress cyclin D1 expression and negatively regulate B cell proliferation suggesting that it acts as an tumour suppressor for lymphoid leukemogenesis. Although canonical Wnt pathway is a 'hot spot' for methylation in acute lymphoblastic leukaemia (ALL), the role of Wnt5a abnormalities has never been evaluated in this clinical setting. The methylation status of the WNT5A promoter was analysed by methylation-specific PCR (MSP) and sequencing in six ALL-derived cell lines (TOM-1, NALM-20, MY, LOUCY, JURKAT and TANOUE) and in 307 ALL patients.
View Article and Find Full Text PDFThe aim of our study was to determine the potential mechanism(s) implicated in Imatinib resistance in patients with Ph+ ALL. Resistance of Ph+ ALL cells to Imatinib-induced apoptosis was associated with lack of inhibition of Akt phosphorylation. Addition of the PI3K inhibitor LY294002 to Imatinib significantly increased apoptosis of Ph+ ALL cells.
View Article and Find Full Text PDFRepetitive elements are heavily methylated in normal tissues, but hypomethylated in malignant tissues, driving the global genomic hypomethylation found in cancer. This hypomethylation results in chromosomal instability, a well-characterized feature of the advanced phases of chronic myeloid leukemia (CML). We investigated methylation changes of DNA repetitive elements (LINE1, Alu, Satellite-alpha and Satellite-2) during the progression of CML from chronic phase (CP) to blast crisis (BC).
View Article and Find Full Text PDFThe hallmark of acute lymphoblastic leukemia (ALL) is a progressive appearance of malignant cell behavior that is triggered by the evolution of altered gene function. ALL has traditionally been viewed as a genetic disease; however, epigenetic defects also play an important role. DNA promoter methylation has gained increasing recognition as an important mechanism for transcriptional silencing of tumor-suppressor genes.
View Article and Find Full Text PDFTumor associated antigens (TAA) provide attractive targets for cancer-specific immunotherapy. PRAME is a TAA gene up-regulated in advanced phases of chronic myeloid leukemia (CML). To date, molecular mechanisms for the expression of PRAME have never been studied.
View Article and Find Full Text PDFBackground And Objectives: Cancer testis antigens (CTA) provide attractive targets for cancer-specific immunotherapy. Although CTA genes are expressed in some normal tissues, such as the testis, this immunologically protected site lacks MHC I expression and as such, does not present self antigens to T cells. To date, CTA genes have been shown to be expressed in a range of solid tumors via demethylation of their promoter CpG islands, but rarely in chronic myeloid leukemia (CML) or other hematologic malignancies.
View Article and Find Full Text PDFActivation of the Wnt/beta-catenin signaling pathway is a hallmark of a number of solid tumors. We analyzed the regulation of the Wnt/beta-catenin pathway in acute lymphoblastic leukemia (ALL) and its role in the pathogenesis of the disease. We found that expression of the Wnt inhibitors sFRP1, sFRP2, sFRP4, sFRP5, WIF1, Dkk3, and Hdpr1 was down-regulated due to abnormal promoter methylation in ALL cell lines and samples from patients with ALL.
View Article and Find Full Text PDFPurpose: To examine cancer genes undergoing epigenetic inactivation in a set of ETV6/RUNX1-positive acute lymphoblastic leukemias in order to define the CpG island methylator phenotype (CIMP) in the disease and evaluate its relationship with clinical features and outcome.
Experimental Design: Methylation-specific PCR was used to analyze the methylation status of 38 genes involved in cell immortalization and transformation in 54 ETV6/RUNX1-positive samples in comparison with 190 ETV6/RUNX1-negative samples.
Results: ETV6/RUNX1-positive samples had at least one gene methylated in 89% of the cases.
The DBC1 gene is a potential tumour suppressor gene that is commonly hypermethylated in epithelial cancers. We studied the role of promoter hypermethylation in the regulation of DBC1 in acute lymphoblastic leukaemia (ALL) cell lines and 170 ALL patients at diagnosis. Abnormal methylation of DBC1 was observed in all ALL cell lines and in 17% of ALL patients.
View Article and Find Full Text PDFWe have analyzed the regulation and expression of ASPP members, genes implicated in the regulation of the apoptotic function of the TP53 tumor-suppressor gene, in acute lymphoblastic leukemia (ALL). Expression of ASPP1 was significantly reduced in ALL and was dependent on hypermethylation of the ASPP1 gene promoter. Abnormal ASPP1 expression was associated with normal function of the tumor-suppressor gene TP53 in ALL.
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