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Find video protocols related to scientific articles indexed in Pubmed.
Dinaciclib, a novel CDK inhibitor, demonstrates encouraging single agent activity in patients with relapsed multiple myeloma.
Blood
PUBLISHED: 11-15-2014
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Dysregulation of cyclin dependent kinases is a hallmark of myeloma, and specifically cdk5 inhibition can enhance the activity of proteasome inhibitors in vitro. Dinaciclib is a novel, potent, small molecule inhibitor of CDK1, CDK 2, CDK 5 and CDK9. Patients with relapsed MM and no more than 5 prior lines of therapy, with measurable disease, were enrolled. Dinaciclib was administered on day 1 of a 21-day cycle at doses of 30-50 mg/m(2). Overall, 27 evaluable patients were accrued; median number of prior therapies was 4. The dose level of 50 mg/m(2) was determined to be the MTD. The overall confirmed response rate (?PR) was 3 of 27 (11%); including one patient at 30 mg/m(2) dose (1 VGPR) and two patients at 40 mg/m(2) dose (1 VGPR, 1 PR). In addition, two patients at 50 mg/mg(2) dose have achieved an MR (Clinical Benefit Rate 19%). Leukopenia, thrombocytopenia, gastrointestinal symptoms, alopecia, and fatigue, were the most common adverse events. The current study demonstrates single agent activity of dinaciclib in relapsed myeloma with 2 patients achieving a deep response (VGPR) and 10 patients obtaining some degree of M protein stabilization or decrease. Ongoing studies are examining dinaciclib in combination with proteasome inhibitors.
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Expression of the Chemokine Receptor Gene, CCR8, is Associated With DUSP22 Rearrangements in Anaplastic Large Cell Lymphoma.
Appl. Immunohistochem. Mol. Morphol.
PUBLISHED: 11-13-2014
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Anaplastic large cell lymphoma (ALCL) is one of the most common T-cell non-Hodgkin lymphomas and has 2 main subtypes: an anaplastic lymphoma kinase (ALK)-positive subtype characterized by ALK gene rearrangements and an ALK-negative subtype that is poorly understood. We recently identified recurrent rearrangements of the DUSP22 locus on 6p25.3 in both primary cutaneous and systemic ALK-negative ALCLs. This study aimed to determine the relationship between these rearrangements and expression of the chemokine receptor gene, CCR8. CCR8 has skin-homing properties and has been suggested to play a role in limiting extracutaneous spread of primary cutaneous ALCLs. However, overexpression of CCR8 has also been reported in systemic ALK-negative ALCLs. As available antibodies for CCR8 have shown lack of specificity, we examined CCR8 expression using quantitative real-time PCR in frozen tissue and RNA in situ hybridization (ISH) in paraffin tissue. Both approaches showed higher CCR8 expression in ALCLs with DUSP22 rearrangements than in nonrearranged cases (PCR: 19.5-fold increase, P=0.01; ISH: 3.3-fold increase, P=0.0008). CCR8 expression was not associated with cutaneous presentation, cutaneous biopsy site, or cutaneous involvement during the disease course. These findings suggest that CCR8 expression in ALCL is more closely related to the presence of DUSP22 rearrangements than to cutaneous involvement and that the function of CCR8 may extend beyond its skin-homing properties in this disease. This study also underscores the utility of RNA-ISH as a paraffin-based method for investigating gene expression when reliable antibodies for immunohistochemical analysis are not available.
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EBV-associated T/NK-cell lymphoproliferative disorder in children and young adults has similar molecular signature to extranodal nasal NK/T-cell lymphoma but shows distinctive stem cell-like phenotype.
Leuk. Lymphoma
PUBLISHED: 11-11-2014
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Abstract We performed gene expression profiling in EBV-associated T/NK-cell lymphoproliferative disorder in children and young adults (TNKLPDC) in order to understand the molecular pathways deregulated in this disease and compared it with nasal-type NK/T-cell lymphoma (NKTL). The molecular and phenotypic signature of TNKLPDC is similar to NKTL with overexpression of p53, survivin and EZH2. Down-regulation of EZH2 in TNKLPDC cell lines lead to increase in apoptosis and decrease in tumor viability, suggesting that EZH2 may be important for the survival of TNKLPDC cells and hence potentially a useful therapeutic target. Notably, our GEP revealed a distinctive enrichment of stem cell related genes in TNKLPDC compared to NKTL. This is validated by a significantly higher expression of ALDH1 in TNKLPDC cell lines compared to NKTL cell lines. The novel discovery of cancer stem cell properties in TNKLPDC has potential therapeutic implications in this group of disorders.
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Clinical Characteristics and Outcome of Thyroid Storm: A Case Series and Review of Neuropsychiatric Derangements in Thyrotoxicosis.
Endocr Pract
PUBLISHED: 11-06-2014
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The objectives were, firstly, to describe the presentation, demographics and clinical course of patients admitted for thyroid storm, and secondly, to identify factors associated with mortality.METHODS: A retrospective review of subjects admitted to a single academic hospital from 2006 through 2011 was conducted. Medical records of all patients who were admitted with diagnosis of thyrotoxicosis were systematically reviewed for clinical features of thyroid storm.RESULTS: A total of 28 cases were identified. Thyroid storm was the first clinical presentation of thyrotoxicosis in 13 patients (46.4%). Non-compliance to treatment was a major trigger in previously diagnosed patients, followed by infection. Mortality rate was 25% in this series. Cardiac manifestations were predominant, with > 60% of patients having severe tachycardia (> 140/min) and/or atrial fibrillation. Although central nervous system (CNS) involvement was less frequent (n = 8, 28.6%), CNS derangements worse than mild severity was statistically associated with mortality (P= 0.021). There was good agreement between the Burch-Wartofsky Point Scale and Japanese Thyroid Association criteria in the diagnosis of thyroid storm in this study cohort.CONCLUSION: Thyroid storm was the first presentation of thyrotoxicosis in a significant proportion of patients, highlighting the importance of high index of suspicion in appropriate clinical context. Presence of neuropsychiatric manifestations appeared to portend greater risk of mortality. Prevailing evidence suggest complex interactions between thyroid hormones and neurotransmitter circuits in the pathogenesis of CNS symptomology in thyrotoxicosis.
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Establishment and Characterization of Novel Human Primary and Metastatic Anaplastic Thyroid Cancer Cell Lines and Their Genomic Evolution Over a Year as a Primagraft.
J. Clin. Endocrinol. Metab.
PUBLISHED: 11-04-2014
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Context: Anaplastic thyroid cancer (ATC) has no effective treatment, resulting in a high rate of mortality. We established cell lines from a primary ATC and its lymph node metastasis, and investigated the molecular factors and genomic changes associated with tumor growth. Objective: The aim of the study was to understand the molecular and genomic changes of highly aggressive ATC and its clonal evolution to develop rational therapies. Design: We established unique cell lines from primary (OGK-P) and metastatic (OGK-M) ATC specimen, as well as primagraft from the metastatic ATC, which was serially xeno-transplanted for more than 1 year in NSG mice were established. These cell lines and primagraft were used as tools to examine gene expression, copy number changes, and somatic mutations using RNA array, SNP Chip, and whole exome sequencing. Results: Mice carrying subcutaneous (OGK-P and OGK-M) tumors developed splenomegaly and neutrophilia with high expression of cytokines including CSF1, CSF2, CSF3, IL-1?, and IL-6. Levels of HIF-1? and its targeted genes were also elevated in these tumors. The treatment of tumor carrying mice with Bevacizumab effectively decreased tumor growth, macrophage infiltration, and peripheral WBCs. SNP chip analysis showed homozygous deletion of exons 3-22 of the PARD3 gene in the cells. Forced expression of PARD3 decreased cell proliferation, motility, and invasiveness, restores cell-cell contacts and enhanced cell adhesion. Next generation exome sequencing identified the somatic changes present in the primary, metastatic, and primagraft tumors demonstrating evolution of the mutational signature over the year of passage in vivo. Conclusion: To our knowledge, we established the first paired human primary and metastatic ATC cell lines offering unique possibilities for comparative functional investigations in vitro and in vivo. Our exome sequencing also identified novel mutations, as well as clonal evolution in both the metastasis and primagraft.
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MoS2 exhibits stronger toxicity with increased exfoliation.
Nanoscale
PUBLISHED: 10-24-2014
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MoS2 belong to a class of inorganic 2D nanomaterials known as transition metal dichalcogenides (TMDs) which have recently attracted a renewed and growing interest due to their interesting electronic and catalytic properties when scaled down to single or few layer sheets. Although exfoliated MoS2 nanosheets have been proposed for numerous energy-related and biosensing applications, little is known about the toxicological impacts of using MoS2 nanosheets. Here, we report about the in vitro toxicity of MoS2 nanosheets that have been chemically exfoliated with different lithium intercalating agents and compared their respective cytotoxic influence. Methyllithium (Me-Li), n-butyllithium (n-Bu-Li) and tert-butyllithium (t-Bu-Li) were used for the exfoliation of bulk MoS2 and we found the t-Bu-Li and n-Bu-Li exfoliated MoS2 nanosheets to be more cytotoxic than MoS2 exfoliated by Me-Li. t-Bu-Li and n-Bu-Li provide more efficient exfoliation over Me-Li, and we establish that the extent of exfoliation that MoS2 undergo is a factor influencing their toxicity. Specifically, the more exfoliated the MoS2 nanosheets, the stronger its cytotoxic influence, which may be due to an increase in surface area and active edge sites. The potential toxicity of these MoS2 nanosheets should be taken into account before their employment in real world applications and we have shown the effect the amount of exfoliation can have on the toxicity of MoS2 nanosheets, representing the first step towards a better understanding of their toxicological properties.
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T-Cell Profile in Adipose Tissue Is Associated With Insulin Resistance and Systemic Inflammation in Humans.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 10-23-2014
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The biological mechanisms linking obesity to insulin resistance have not been fully elucidated. We have shown that insulin resistance or glucose intolerance in diet-induced obese mice is related to a shift in the ratio of pro- and anti-inflammatory T cells in adipose tissue. We sought to test the hypothesis that the balance of T-cell phenotypes would be similarly related to insulin resistance in human obesity.
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Reversing the Temporal Envelope of a Heralded Single Photon using a Cavity.
Phys. Rev. Lett.
PUBLISHED: 10-15-2014
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We demonstrate a way to prepare single photons with a temporal envelope that resembles the time reversal of photons from the spontaneous decay process. We use the photon pairs generated from a time-ordered cascade decay: the detection of the first photon of the cascade is used as a herald for the ground-state transition resonant second photon. We show how the interaction of the heralding photon with an asymmetric Fabry-Perot cavity reverses the temporal shape of its twin photon from a decaying to a rising exponential envelope. This single photon is expected to be ideal for interacting with two-level systems.
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Draft Genome Sequence of Polychlorinated Biphenyl-Dechlorinating Dehalococcoides mccartyi Strain SG1, Which Carries a Circular Putative Plasmid.
Genome Announc
PUBLISHED: 10-04-2014
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Dehalococcoides mccartyi strain SG1, isolated from digester sludge, dechlorinates polychlorinated biphenyls (PCBs) to lower congeners. Here we report the draft genome sequence of SG1, which carries a 22.65 kbp circular putative plasmid.
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B-1a Lymphocytes Attenuate Insulin Resistance.
Diabetes
PUBLISHED: 09-23-2014
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Obesity-associated insulin resistance, a common precursor of type 2 diabetes, is characterized by chronic inflammation of tissues, including visceral adipose tissue (VAT). Here we show that B-1a cells, a subpopulation of B lymphocytes, are novel and important regulators of this process. B-1a cells are reduced in frequency in obese high-fat diet (HFD)-fed mice, and EGFP interleukin-10 (IL-10) reporter mice show marked reductions in anti-inflammatory IL-10 production by B cells in vivo during obesity. In VAT, B-1a cells are the dominant producers of B cell-derived IL-10, contributing nearly half of the expressed IL-10 in vivo. Adoptive transfer of B-1a cells into HFD-fed B cell-deficient mice rapidly improves insulin resistance and glucose tolerance through IL-10 and polyclonal IgM-dependent mechanisms, whereas transfer of B-2 cells worsens metabolic disease. Genetic knockdown of B cell-activating factor (BAFF) in HFD-fed mice or treatment with a B-2 cell-depleting, B-1a cell-sparing anti-BAFF antibody attenuates insulin resistance. These findings establish B-1a cells as a new class of immune regulators that maintain metabolic homeostasis and suggest manipulation of these cells as a potential therapy for insulin resistance.
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Primary Cutaneous NK/T-cell Lymphoma, Nasal Type and CD56-positive Peripheral T-cell Lymphoma: A Cellular Lineage and Clinicopathologic Study of 60 Patients From Asia.
Am. J. Surg. Pathol.
PUBLISHED: 09-03-2014
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Primary cutaneous, extranodal natural killer/T-cell lymphoma, nasal type (PC-ENKTL), is a rare Epstein-Barr virus (EBV)-associated neoplasm with poorly defined clinicopathologic features. We performed a multinational retrospective study of PC-ENKTL and CD56-positive EBV-negative peripheral T-cell lymphoma (PC-CD56+PTCL) in Asia in an attempt to elucidate their clinicopathologic features. Using immunohistochemistry for T-cell receptors (TCRs), in situ hybridization for EBV, and TCR gene rearrangement, we classified 60 tumors into 51 with PC-ENKTL (20 of NK-cell, 17 T-cell, and 14 indeterminate lineages) and 9 with PC-CD56+PTCL. Tumors of T-cell origin accounted for 46% of PC-ENKTLs with half of these cases being TCR-silent. As compared with T-lineage tumors, PC-ENKTLs of NK-cell lineage had more frequent involvement of regional lymph nodes and more frequently CD8-negative and CD56-positive. Cases of PC-ENKTL showed more frequent tumor necrosis, younger age, and a higher frequency of CD16 and CD30 expression than cases of PC-CD56+PTCL. CD56-positive T-lineage PC-ENKTL tumors (n=8) had more localized disease in the TNM (tumor-node-metastasis) staging and were more often of ?? T-cell origin compared with cases of PC-CD56+PTCL (n=9). PC-ENKTLs and PC-CD56+PTCLs were equally aggressive, with a 5-year overall survival rate of 25%. Tumor necrosis and CD16 expression may serve as useful surrogates for differentiating PC-ENKTL from PC-CD56+PTCL. A single lesion, an elevated lactate dehydrogenase level, and the presence of B symptoms were independent poor prognostic factors for PC-ENKTL in multivariate analysis. Further studies with more cases are warranted to delineate the clinicopathologic features and significance of EBV in these rare lymphomas.
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Combination of vaccine-strain measles and mumps virus synergistically kills a wide range of human hematological cancer cells: Special focus on acute myeloid leukemia.
Cancer Lett.
PUBLISHED: 09-01-2014
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Through combining vaccine-derived measles and mumps viruses (MM), we efficiently targeted a wide range of hematopoietic cancer cell lines. MM synergistically killed many cell lines including acute myeloid leukemia (AML) cell lines. Further investigation suggested that enhanced oncolytic effect of MM was due to increased apoptosis induction. In an U937 xenograft AML mouse model, MM displayed greater tumor suppression and prolonged survival. Furthermore, MM efficiently killed blasts from 16 out of 20 AML patients and elicited more efficient killing effect on 11 patients when co-administered with Ara-C. Our results demonstrate that MM is a promising therapeutic candidate for hematological malignancies.
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Intrathyroidal Ectopic Thymic Tissue Mimicking Thyroid Cancer in Children.
Endocr Pract
PUBLISHED: 08-22-2014
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Objective: To increase awareness of important differential diagnosis between thyroid cancer and intrathyroidal ectopic thymic tissue when performing neck ultrasounds in childrenMethod: We report two cases of intrathyrodal thymic tissue that were initially referred as possible papillary thyroid cancer. Ultrasound (US) and cytological features of these lesions are described and the distinguishing ultrasound characteristics of intrathyroidal thymic tissue versus papillary thyroid cancers are discussed.Results: Two children who underwent thyroid US were diagnosed with thyroid nodule which features suggested papillary thyroid cancer. In both patients, suspected lesions exhibited echo texture identical to the normal thymus gland. Fine needle aspirate of the nodule in the first child revealed numerous lymphocytes with positive immunocytochemical stain for CD3, confirming T cell phenotype. The second child had follow up ultrasound imaging 8 months later which showed stability of the intrathyroidal nodule.Conclusion: Intrathyroidal ectopic thymic tissue can be mistaken for papillary thyroid cancer as both conditions have similar US features. The increase awareness of this unique mimicry may help to avoid unnecessary invasive investigations and surgery in these young patients.
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Phosphatase of regenerating liver-3 (PRL-3) is regulated by STAT3 in acute myeloid leukemia.
Exp. Hematol.
PUBLISHED: 08-16-2014
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Over-expression of PRL-3 has been identified in about 50% of patients with acute myeloid leukemia (AML). The mechanism of regulation of PRL-3 remains obscure. Signal transducer and activator of transcription 3 (STAT3), a latent transcriptional factor, has also been often found to be activated in AML. We first identified consensus STAT3 binding sites in the promoter of PRL-3 genes. Then we experimentally validated the direct binding and transcriptional activation. shRNA-mediated knockdown and overexpression approaches were applied in STAT3(-/-) liver cells and leukemic cells to validate the functional regulation of PRL-3 by STAT3. A STAT3 core signature, derived through data mining from publicly available gene expression data, was employed to correlate PRL-3 expression in large AML patient samples. We discovered that STAT3 binds to the -201 to -210 region of PRL-3, which was conserved between human and mouse. Importantly, PRL-3 protein was significantly reduced in mouse STAT3 knockout liver cells compared to STAT3-WT counterparts and ectopic expression of STAT3 in these cells led to a pronounced increase in PRL-3 protein. We demonstrated that STAT3 functionally regulated PRL-3 and STAT3 core signature was enriched in AML with high PRL-3 expression. Targeting either STAT3 or PRL-3 reduced leukemic cell viability. Silencing PRL-3 impaired invasiveness and induced leukemic cell differentiation. In conclusion, PRL-3 was transcriptionally regulated by STAT3. The STAT3/PRL-3 regulatory loop contributes to the pathogenesis of AML and it might represent an attractive therapeutic target for antileukemic therapy.
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The role of the cytopathologist's interpretation in achieving diagnostic adequacy of head and neck fine needle aspirates.
Cytopathology
PUBLISHED: 08-11-2014
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We aimed to assess the potential role of interpretation by cytopathologists on the level of diagnostic adequacy of head and neck fine needle aspirations (FNAs).
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Graphene oxide nanoribbons exhibit significantly greater toxicity than graphene oxide nanoplatelets.
Nanoscale
PUBLISHED: 08-08-2014
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Graphene oxide (GOs) has emerged in recent years as a versatile nanomaterial, demonstrating tremendous potential for multifunctional biomedical applications. GOs can be prepared by the top-down or bottom-up approach, which leads to a great variability of GOs being produced due to the different procedures and starting carbon sources adopted. This will have an effect on the physiochemical properties of GOs and their resultant toxic behavior. In this study, we examined the cytotoxicity of graphene-oxide nanoribbons (GONRs; ?310 × 5000 nm) and graphene-oxide nanoplatelets (GONPs; 100 × 100 nm), prepared from the oxidative treatment of multi-walled carbon nanotubes (MWCNTs; ?100 × 5000 nm) and stacked graphene nanofibers (SGNFs; 100 × 5000 nm), respectively. In vitro assessments revealed that the GONRs exhibited a much stronger cytotoxicity over the GONPs, and we correlated that observation with characterization data that showed GONRs to have a greater amount of carbonyl groups as well as greater length. Therefore, we put forward that the stronger toxic behavior of GONRs is a result of the synergistic effect between these two factors, and the type of carbon source used to prepare GOs should be carefully considered in any future bioapplications.
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Identification and targeting leukemia stem cells: The path to the cure for acute myeloid leukemia.
World J Stem Cells
PUBLISHED: 07-22-2014
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Accumulating evidence support the notion that acute myeloid leukemia (AML) is organized in a hierarchical system, originating from a special proportion of leukemia stem cells (LSC). Similar to their normal counterpart, hematopoietic stem cells (HSC), LSC possess self-renewal capacity and are responsible for the continued growth and proliferation of the bulk of leukemia cells in the blood and bone marrow. It is believed that LSC are also the root cause for the treatment failure and relapse of AML because LSC are often resistant to chemotherapy. In the past decade, we have made significant advancement in identification and understanding the molecular biology of LSC, but it remains a daunting task to specifically targeting LSC, while sparing normal HSC. In this review, we will first provide a historical overview of the discovery of LSC, followed by a summary of identification and separation of LSC by either cell surface markers or functional assays. Next, the review will focus on the current, various strategies for eradicating LSC. Finally, we will highlight future directions and challenges ahead of our ultimate goal for the cure of AML by targeting LSC.
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Genomic characterization of three unique Dehalococcoides that respire on persistent polychlorinated biphenyls.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-15-2014
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Fastidious anaerobic bacteria play critical roles in environmental bioremediation of halogenated compounds. However, their characterization and application have been largely impeded by difficulties in growing them in pure culture. Thus far, no pure culture has been reported to respire on the notorious polychlorinated biphenyls (PCBs), and functional genes responsible for PCB detoxification remain unknown due to the extremely slow growth of PCB-respiring bacteria. Here we report the successful isolation and characterization of three Dehalococcoides mccartyi strains that respire on commercial PCBs. Using high-throughput metagenomic analysis, combined with traditional culture techniques, tetrachloroethene (PCE) was identified as a feasible alternative to PCBs to isolate PCB-respiring Dehalococcoides from PCB-enriched cultures. With PCE as an alternative electron acceptor, the PCB-respiring Dehalococcoides were boosted to a higher cell density (1.2 × 10(8) to 1.3 × 10(8) cells per mL on PCE vs. 5.9 × 10(6) to 10.4 × 10(6) cells per mL on PCBs) with a shorter culturing time (30 d on PCE vs. 150 d on PCBs). The transcriptomic profiles illustrated that the distinct PCB dechlorination profile of each strain was predominantly mediated by a single, novel reductive dehalogenase (RDase) catalyzing chlorine removal from both PCBs and PCE. The transcription levels of PCB-RDase genes are 5-60 times higher than the genome-wide average. The cultivation of PCB-respiring Dehalococcoides in pure culture and the identification of PCB-RDase genes deepen our understanding of organohalide respiration of PCBs and shed light on in situ PCB bioremediation.
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Multifocal interferometric synthetic aperture microscopy.
Opt Express
PUBLISHED: 07-01-2014
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There is an inherent trade-off between transverse resolution and depth of field (DOF) in optical coherence tomography (OCT) which becomes a limiting factor for certain applications. Multifocal OCT and interferometric synthetic aperture microscopy (ISAM) each provide a distinct solution to the trade-off through modification to the experiment or via post-processing, respectively. In this paper, we have solved the inverse problem of multifocal OCT and present a general algorithm for combining multiple ISAM datasets. Multifocal ISAM (MISAM) uses a regularized combination of the resampled datasets to bring advantages of both multifocal OCT and ISAM to achieve optimal transverse resolution, extended effective DOF and improved signal-to-noise ratio. We present theory, simulation and experimental results.
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Palladium nanomaterials in catalytic intramolecular C-H amination reactions.
Chem. Commun. (Camb.)
PUBLISHED: 06-26-2014
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Supported palladium nanomaterials catalyzed an intramolecular C-H amination reaction to produce carbazoles in moderate to excellent isolated yields, up to 92%.
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Lipid-associated aggregate formation of superoxide dismutase-1 is initiated by membrane-targeting loops.
Proteins
PUBLISHED: 05-21-2014
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Copper-Zinc superoxide dismutase 1 (SOD1) is a homodimeric enzyme that protects cells from oxidative damage. Hereditary and sporadic amyotrophic lateral sclerosis may be linked to SOD1 when the enzyme is destabilized through mutation or environmental stress. The cytotoxicity of demetallated or apo-SOD1 aggregates may be due to their ability to cause defects within cell membranes by co-aggregating with phospholipids. SOD1 monomers may associate with the inner cell membrane to receive copper ions from membrane-bound copper chaperones. But how apo-SOD1 interacts with lipids is unclear. We have used atomistic molecular dynamics simulations to reveal that flexible electrostatic and zinc-binding loops in apo-SOD1 dimers play a critical role in the binding of 1-octanol clusters and phospholipid bilayer, without any significant unfolding of the protein. The apo-SOD1 monomer also associates with phospholipid bilayer via its zinc-binding loop rather than its exposed hydrophobic dimerization interface. Our observed orientation of the monomer on the bilayer would facilitate its association with a membrane-bound copper chaperone. The orientation also suggests how membrane-bound monomers could act as seeds for membrane-associated SOD1 aggregation. Proteins 2014; 82:3194-3209. © 2014 Wiley Periodicals, Inc.
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Infinium monkeys: Infinium 450K array for the Cynomolgus macaque (Macaca fascicularis).
G3 (Bethesda)
PUBLISHED: 05-13-2014
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The Infinium Human Methylation450 BeadChip Array (Infinium 450K) is a robust and cost-efficient survey of genome-wide DNA methylation patterns. Macaca fascicularis (Cynomolgus macaque) is an important disease model; however, its genome sequence is only recently published, and few tools exist to interrogate the molecular state of Cynomolgus macaque tissues. Although the Infinium 450K is a hybridization array designed to the human genome, the relative conservation between the macaque and human genomes makes its use in macaques feasible. Here, we used the Infinium 450K array to assay DNA methylation in 11 macaque muscle biopsies. We showed that probe hybridization efficiency was related to the degree of sequence identity between the human probes and the macaque genome sequence. Approximately 61% of the Human Infinium 450K probes could be reliably mapped to the Cynomolgus macaque genome and contain a CpG site of interest. We also compared the Infinium 450K data to reduced representation bisulfite sequencing data generated on the same samples and found a high level of concordance between the two independent methodologies, which can be further improved by filtering for probe sequence identity and mismatch location. We conclude that the Infinium 450K array can be used to measure the DNA methylome of Cynomolgus macaque tissues using the provided filters. We also provide a pipeline for validation of the array in other species using a simple BLAST-based sequence identify filter.
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Allogeneic haematopoietic SCT for natural killer/T-cell lymphoma: a multicentre analysis from the Asia Lymphoma Study Group.
Bone Marrow Transplant.
PUBLISHED: 04-28-2014
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Eighteen patients (men=14; women=4) with natural killer (NK)/T-cell lymphomas (CR1, N=9; CR2, N=7; PR, N=1; progressive disease, N=1) undergoing allogeneic haematopoietic SCT (HSCT) (myeloablative, N=14; reduced intensity, N=4) were analyzed. With a median follow-up of 20.5 months, the 5-year OS was 57% and 5-year EFS was 51%. The use of the SMILE regimen pre-HSCT was the most important positive prognostic indicator, resulting in significantly superior OS and EFS (P<0.01). Acute GVHD had a significant negative impact on OS (P=0.03). CR1 and CR2 patients had similar survivals, but all patients who were not transplanted in remission died. Chronic GVHD, International Prognostic Index, disease stage, primary sites of involvement, conditioning regimen and source of HSC did not affect survival. Although allogeneic HSCT leads to reasonable survival for NK/T-cell lymphoma patients, results need to be compared with those in patients receiving L-asparaginase-containing regimens. Novel prognostic models incorporating biomarkers, such as circulating EBV DNA, are needed to identify high-risk patients who may benefit from allogeneic HSCT.
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A retrospective study on sequential desensitization-rechallenge for antituberculosis drug allergy.
Asia Pac Allergy
PUBLISHED: 04-20-2014
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Antituberculosis (anti-TB) drug allergy often involves multiple concurrently administered drugs which subsequently need to be reinitiated as no better alternatives exist.
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Alterations to DNA methylation and expression of CXCL14 are associated with suboptimal birth outcomes.
J. Hum. Genet.
PUBLISHED: 04-15-2014
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CXCL14 is a chemokine that has previously been implicated in insulin resistance in mice. In humans, the role of CXCL14 in metabolic processes is not well established, and we sought to determine whether CXCL14 is a risk susceptibility gene important in fetal programming of metabolic disease. For this purpose, we investigated whether CXCL14 is differentially regulated in human umbilical cords of infants with varying birth weights. We found an elevated expression of CXCL14 in human low birth weight (LBW) cords, as well as in cords from nutritionally restricted Macaca fascicularis macaques. To further analyze the regulatory mechanisms underlying the expression of CXCL14, we examined CXCL14 in umbilical cord-derived mesenchymal stem cells (MSCs) that provide an in vitro cell-based system amenable to experimental manipulation. Using both whole frozen cords and MSCs, we determined that site-specific CpG methylation in the CXCL14 promoter is associated with altered expression, and that changes in methylation are evident in LBW infant-derived umbilical cords that may indicate future metabolic compromise through CXCL14.
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Renal pelvis squamous cell carcinoma with inferior vena cava infiltration: Case report and review of the literature.
Int J Surg Case Rep
PUBLISHED: 04-15-2014
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Renal squamous cell carcinoma (RSCC) is a rare tumor that is usually diagnosed late as a locally advanced malignancy with adjacent structure involvement. Radical surgical resection with negative margins is the mainstay of treatment, as it is correlated with improved survival, while other modalities of treatment have been shown to have limited efficacy.
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Extending neurites sense the depth of the underlying topography during neuronal differentiation and contact guidance.
Biomaterials
PUBLISHED: 04-09-2014
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The topography of the extracellular microenvironment influences cell morphology, provides conduct guidance and directs cell differentiation. Aspect ratio and dimension of topography have been shown to affect cell behaviours, but the ability and mechanism of depth-sensing is not clearly understood. We showed that murine neural progenitor cells (mNPCs) can sense the depth of the micro-gratings. Neurite elongation, alignment and neuronal differentiation were observed to increase with grating depth. We proposed a mechanism for depth-sensing by growing neurites: filopodial adhesion in the growth cones favour elongation but the bending rigidity of the neurite cytoskeleton resists it. Thus, perpendicular extension on deeper grooves is unfavourable as neurites need to bend over a larger angle. A quantitative model was developed and its prediction of neurite growth on gratings fit well with the experimental data. The results indicated that mNPC fate can be directed by appropriately designed patterned surfaces.
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LEO1 is regulated by PRL-3 and mediates its oncogenic properties in acute myelogenous leukemia.
Cancer Res.
PUBLISHED: 03-31-2014
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PRL-3, an oncogenic dual-specificity phosphatase, is overexpressed in 50% of acute myelogenous leukemia (AML) and associated with poor survival. We found that stable expression of PRL-3 confers cytokine independence and growth advantage of AML cells. However, how PRL-3 mediates these functions in AML is not known. To comprehensively screen for PRL3-regulated proteins in AML, we performed SILAC-based quantitative proteomics analysis and discovered 398 significantly perturbed proteins after PRL-3 overexpression. We show that Leo1, a component of RNA polymerase II-associated factor (PAF) complex, is a novel and important mediator of PRL-3 oncogenic activities in AML. We described a novel mechanism where elevated PRL-3 protein increases JMJD2C histone demethylase occupancy on Leo1 promoter, thereby reducing the H3K9me3 repressive signals and promoting Leo1 gene expression. Furthermore, PRL-3 and Leo1 levels were positively associated in AML patient samples (N=24; P<0.01). On the other hand, inhibition of Leo1 reverses PRL-3 oncogenic phenotypes in AML. Loss of Leo1 leads to destabilization of the PAF complex and downregulation of SOX2 and SOX4, potent oncogenes in myeloid transformation. In conclusion, we identify an important and novel mechanism by which PRL-3 mediates its oncogenic function in AML.
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Implications of heterogeneity in multiple myeloma.
Biomed Res Int
PUBLISHED: 03-27-2014
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Multiple myeloma is the second most common hematologic malignancy in the world. Despite improvement in outcome, the disease is still incurable for most patients. However, not all myeloma are the same. With the same treatment, some patients can have very long survival whereas others can have very short survival. This suggests that there is underlying heterogeneity in myeloma. Studies over the years have revealed multiple layers of heterogeneity. First, clinical parameters such as age and tumor burden could significantly affect outcome. At the genetic level, there are also significant heterogeneity ranging for chromosome numbers, genetic translocations, and genetic mutations. At the clonal level, there appears to be significant clonal heterogeneity with multiple clones coexisting in the same patient. At the cell differentiation level, there appears to be a hierarchy of clonally related cells that have different clonogenic potential and sensitivity to therapies. These levels of complexities present challenges in terms of treatment and prognostication as well as monitoring of treatment. However, if we can clearly delineate and dissect this heterogeneity, we may also be presented with unique opportunities for precision and personalized treatment of myeloma. Some proof of concepts of such approaches has been demonstrated.
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MicroRNA: important player in the pathobiology of multiple myeloma.
Biomed Res Int
PUBLISHED: 03-26-2014
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Recent studies have revealed a pivotal role played by a class of small, noncoding RNAs, microRNA (miRNA), in multiple myeloma (MM), a plasma cell (PC) malignancy causing significant morbidity and mortality. Deregulated miRNA expression in patient's PCs and plasma has been associated with tumor progression, molecular subtypes, clinical staging, prognosis, and drug response in MM. A number of important oncogenic and tumor suppressor miRNAs have been discovered to regulate important genes and pathways such as p53 and IL6-JAK-STAT signaling. miRNAs may also form complex regulatory circuitry with genetic and epigenetic machineries, the deregulation of which could lead to malignant transformation and progression. The translational potential of miRNAs in the clinic is being increasingly recognized that they could represent novel biomarkers and therapeutic targets. This review comprehensively summarizes current progress in delineating the roles of miRNAs in MM pathobiology and management.
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Cytotoxicity of exfoliated transition-metal dichalcogenides (MoS2 , WS2 , and WSe2 ) is lower than that of graphene and its analogues.
Chemistry
PUBLISHED: 03-20-2014
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Studies involving transition-metal dichalcogenides (TMDs) have been around for many decades and in recent years, many were focused on using TMDs to synthesize inorganic analogues of carbon nanotubes, fullerene, as well as graphene and its derivatives with the ultimate aim of employing these materials into consumer products. In view of this rising trend, we investigated the cytotoxicity of three common exfoliated TMDs (exTMDs), namely MoS2 , WS2 , and WSe2 , and compared their toxicological effects with graphene oxides and halogenated graphenes to find out whether these inorganic analogues of graphenes and derivatives would show improved biocompatibility. Based on the cell viability assessments using methylthiazolyldiphenyl-tetrazolium bromide (MTT) and water-soluble tetrazolium salt (WST-8) assays on human lung carcinoma epithelial cells (A549) following a 24?h exposure to varying concentrations of the three exTMDs, it was concluded that MoS2 and WS2 nanosheets induced very low cytotoxicity to A549 cells, even at high concentrations. On the other hand, WSe2 exhibited dose-dependent toxicological effects on A549 cells, reducing cell viability to 31.8?% at the maximum concentration of 400??g?mL(-1) ; the higher cytotoxicity displayed by WSe2 might be linked to the identity of the chalcogen. In comparison with graphene oxides and halogenated graphenes, MoS2 and WS2 were much less hazardous, whereas WSe2 showed similar degree of cytotoxicity. Future in-depth studies should be built upon this first work on the in vitro cytotoxicity of MoS2 and WS2 to ensure that they do not pose acute toxicity. Lastly, nanomaterial-induced interference control experiments revealed that exTMDs were capable of reacting with MTT assay viability markers in the absence of cells, but not with WST-8 assay. This suggests that the MTT assay is not suitable for measuring the cytotoxicity of exTMDs because inflated results will be obtained, giving false impressions that the materials are less toxic.
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To what extent do tutor-related behaviours influence student learning in PBL?
Adv Health Sci Educ Theory Pract
PUBLISHED: 03-19-2014
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The purpose of this study was to investigate how tutor behaviours influence learning in problem-based learning (PBL). A previous study had indicated a significant influence of the tutor's social congruent behaviour on the PBL process and this study further investigates this finding by examining two groups of tutors displaying differences in social congruence. The participants were 77 students under the tutelage of four tutors and a self-report questionnaire ranked two tutors to be more socially congruent as compared to the other two. Student learning was measured by a concept recall test and the results from the analysis of covariance indicated a significant impact of the tutor's social congruent behaviour on learning after the problem analysis phase but not on the self-directed learning and reporting phases. It was concluded that the academic abilities of students and the small number of tutors involved may have affected the results, which led to the second part of this study. A group of 11 tutors were selected and the impact of their behaviours on student achievement measured by the module grade was examined. Results indicated that the tutor behaviours had a greater influence on average students as compared to the academically stronger and weaker students. This finding suggests that students who are academically stronger are not as reliant on the tutor while average students may depend more on the tutor to guide and motivate them in order to achieve the learning goals.
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MMSET: role and therapeutic opportunities in multiple myeloma.
Biomed Res Int
PUBLISHED: 03-17-2014
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Recurrent chromosomal translocations are central to the pathogenesis, diagnosis, and prognosis of hematologic malignancies. The translocation t(4; 14)(p16; q32) is one of the most common translocations in multiple myeloma (MM) and is associated with very poor prognosis. The t(4; 14) translocation leads to the simultaneous overexpression of two genes, FGFR3 (fibroblast growth factor receptor 3) and MMSET (multiple myeloma SET domain), both of which have potential oncogenic activity. However, approximately 30% of t(4; 14)?MM patients do not express FGFR3 and have poor prognosis irrespective of FGFR3 expression, whereas MMSET overexpression is universal in t(4; 14) cases. In this review, we provide an overview of recent findings regarding the oncogenic roles of MMSET in MM and its functions on histone methylation. We also highlight some of MMSET partners and its downstream signalling pathways and discuss the potential therapeutics targeting MMSET.
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p53 abnormalities and potential therapeutic targeting in multiple myeloma.
Biomed Res Int
PUBLISHED: 03-17-2014
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p53 abnormalities are regarded as an independent prognostic marker in multiple myeloma. Patients harbouring this genetic anomaly are commonly resistant to standard therapy. Thus, various p53 reactivating agents have been developed in order to restore its tumour suppressive abilities. Small molecular compounds, especially, have gained popularity in its efficacy against myeloma cells. For instance, promising preclinical results have steered both nutlin-3 and PRIMA-1 into phase I/II clinical trials. This review summarizes different modes of p53 inactivation in myeloma and highlights the current p53-based therapies that are being utilized in the clinic. Finally, we discuss the potential and promise that the novel small molecules possess for clinical application in improving the treatment outcome of myeloma.
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Transforming Growth Factor ?/Activin Signaling Functions as a Sugar-Sensing Feedback Loop to Regulate Digestive Enzyme Expression.
Cell Rep
PUBLISHED: 02-20-2014
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Organisms need to assess their nutritional state and adapt their digestive capacity to the demands for various nutrients. Modulation of digestive enzyme production represents a rational step to regulate nutriment uptake. However, the role of digestion in nutrient homeostasis has been largely neglected. In this study, we analyzed the mechanism underlying glucose repression of digestive enzymes in the adult Drosophila midgut. We demonstrate that glucose represses the expression of many carbohydrases and lipases. Our data reveal that the consumption of nutritious sugars stimulates the secretion of the transforming growth factor ? (TGF-?) ligand, Dawdle, from the fat body. Dawdle then acts via circulation to activate TGF-?/Activin signaling in the midgut, culminating in the repression of digestive enzymes that are highly expressed during starvation. Thus, our study not only identifies a mechanism that couples sugar sensing with digestive enzyme expression but points to an important role of TGF-?/Activin signaling in sugar metabolism.
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Molecular characterization of argininosuccinate synthase and argininosuccinate lyase from the liver of the African lungfish Protopterus annectens, and their mRNA expression levels in the liver, kidney, brain and skeletal muscle during aestivation.
J. Comp. Physiol. B, Biochem. Syst. Environ. Physiol.
PUBLISHED: 02-13-2014
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Argininosuccinate synthase (Ass) and argininosuccinate lyase (Asl) are involved in arginine synthesis for various purposes. The complete cDNA coding sequences of ass and asl from the liver of Protopterus annectens consisted of 1,296 and 1,398 bp, respectively. Phylogenetic analyses revealed that the deduced Ass and Asl of P. annectens had close relationship with that of the cartilaginous fish Callorhinchus milii. Besides being strongly expressed in the liver, ass and asl expression were detectable in many tissues/organs. In the liver, mRNA expression levels of ass and asl increased significantly during the induction phase of aestivation, probably to increase arginine production to support increased urea synthesis. The increases in ass and asl mRNA expression levels during the prolonged maintenance phase and early arousal phase of aestivation could reflect increased demand on arginine for nitric oxide (NO) production in the liver. In the kidney, there was a significant decrease in ass mRNA expression level after 6 months of aestivation, indicating possible decreases in the synthesis and supply of arginine to other tissues/organs. In the brain, changes in ass and asl mRNA expression levels during the three phases of aestivation could be related to the supply of arginine for NO synthesis in response to conditions that resemble ischaemia and ischaemia-reperfusion during the maintenance and arousal phase of aestivation, respectively. The decrease in ass mRNA expression level, accompanied with decreases in the concentrations of arginine and NO, in the skeletal muscle of aestivating P. annectens might ameliorate the potential of disuse muscle atrophy.
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Thymoquinone overcomes chemoresistance and enhances the anticancer effects of bortezomib through abrogation of NF-?B regulated gene products in multiple myeloma xenograft mouse model.
Oncotarget
PUBLISHED: 02-08-2014
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Multiple myeloma (MM) is a B cell malignancy characterized by clonal proliferation of plasma cells in the bone marrow. With the advent of novel targeted agents, the median survival rate has increased to 5 -7 years. However, majority of patients with myeloma suffer relapse or develop chemoresistance to existing therapeutic agents. Thus, there is a need to develop novel alternative therapies for the treatment of MM. Thus in the present study, we investigated whether thymoquinone (TQ), a bioactive constituent of black seed oil, could suppress the proliferation and induce chemosensitization in human myeloma cells and xenograft mouse model. Our results show that TQ inhibited the proliferation of MM cells irrespective of their sensitivity to doxorubicin, melphalan or bortezomib. Interestingly, TQ treatment also resulted in a significant inhibition in the proliferation of CD138+ cells isolated from MM patient samples in a concentration dependent manner. TQ also potentiated the apoptotic effects of bortezomib in various MM cell lines through the activation of caspase-3, resulting in the cleavage of PARP. TQ treatment also inhibited chemotaxis and invasion induced by CXCL12 in MM cells. Furthermore, in a xenograft mouse model, TQ potentiated the antitumor effects of bortezomib (p<0.05, vehicle versus bortezomib + TQ; p<0.05, bortezomib versus bortezomib + TQ), and this correlated with modulation of various markers for survival and angiogenesis, such as Ki-67, vascular endothelial growth factor (VEGF), Bcl-2 and p65 expression. Overall, our results demonstrate that TQ can enhance the anticancer activity of bortezomib in vitro and in vivo and may have a substantial potential in the treatment of MM.
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Cytotoxicity profile of highly hydrogenated graphene.
Chemistry
PUBLISHED: 02-06-2014
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Graphene and its graphene-related counterparts have been considered the future of advanced nanomaterials owing to their exemplary properties. An increase in their potential applications in the biomedical field has led to serious concerns regarding their safety and impact on health. To understand the toxicity profile for a particular type of graphene utilized in a given application, it is important to recognize the differences between the graphene-related components and correlate their cellular toxicity effects to the attributed physiochemical properties. In this study, the cytoxicity effects of highly hydrogenated graphene (HHG) and its graphene oxide (GO) counterpart on the basis of in vitro toxicological assessments are reported and the effects correlated with the physiochemical properties of the tested nanomaterials. Upon 24?h exposure to the nanomaterials, a dose-dependent cellular cytotoxic effect was exhibited and the HHG was observed to be more cytotoxic than its GO control. Detailed characterization revealed an extensive C-H sp(3) network on the carbon backbone of HHG with few oxygen-containing groups, as opposed to the presence of large amounts of oxygen-containing groups on the GO. It is therefore hypothesized that the preferential adsorption of micronutrients on the surface of the HHG nanomaterial by means of hydrophobic interactions resulted in a reduction in the bioavailability of nutrients required for cellular viability. The nanotoxicological profile of highly hydrogenated graphene is assessed for the first time in our study, thereby paving the way for further evaluation of the toxicity risks involved with the utilization of various graphene-related nanomaterials in the real world.
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Modified cIg-FISH protocol for multiple myeloma in routine cytogenetic laboratory practice.
Cancer Genet
PUBLISHED: 02-04-2014
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The International Myeloma Working Group recommends that fluorescence in situ hybridization (FISH) be performed on specifically identified plasma cells (PC). This is because chromosomal abnormalities are not frequently detected by traditional karyotyping due to the low proliferative rate of PC in multiple myeloma (MM). Conventional FISH enhances the sensitivity but lacks the specificity, as it does not distinguish PC from other hematopoetic cells. To fulfill this recommendation, PC need to be selected either by flow cytometry or immunomagnetic bead-based PC sorting or by concomitant labeling of the cytoplasmic immunoglobulin light chain, which allows for unambiguous identification. These techniques require expertise, time, and funding and are not easily incorporated into the routine workflow of the cytogenetic laboratory. We have modified and refined the technique using fixed cell pellets to achieve nicely separated and easily identifiable PC. With immunostaining and subsequent FISH (i.e., cytoplasmic immunoglobulin FISH, cIg-FISH), this technique can be easily incorporated into every cytogenetic laboratory. Twenty samples from patients with MM were subjected to routine FISH, cIg-FISH, and chromosomal karyotyping and the results were compared. Three FISH probes, which enabled detection of the t(4;14), t(14;16) and deletion of TP53, were used to validate this modified technique successfully.
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Clinical profiles of multiple myeloma in Asia-An Asian Myeloma Network study.
Am. J. Hematol.
PUBLISHED: 01-23-2014
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The incidence of multiple myeloma (MM) is known to be variable according to ethnicity. However, the differences in clinical characteristics between ethnic groups are not well-defined. In Asian countries, although the incidence of MM has been lower than that of Western countries, there is growing evidence that MM is increasing rapidly. The Asian Myeloma Network decided to initiate the first multinational project to describe the clinical characteristics of MM and the clinical practices in Asia. Data were retrospectively collected from 23 centers in 7 countries and regions. The clinical characteristics at diagnosis, survival rates and initial treatment of 3,405 symptomatic MM patients were described. Median age was 62 years (range, 19-106), with 55.6% of being male. Median overall survival (OS) was 47 months (95% CI 44.0-50.0). Stem cell transplantation was performed in 666 patients who showed better survival rates (79 vs. 41 months, P?
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Gum pigmentation: an unusual adverse effect of sublingual immunotherapy.
Asia Pac Allergy
PUBLISHED: 01-21-2014
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Sublingual immunotherapy has gained acceptance amongst the paediatric community as it is very well tolerated and is safe. The adverse effects of this therapy is minimal consisting mainly of local side effects within the oral cavity such as itching of the mouth, swelling of the lips and less frequently abdominal pain, wheezing and urticaria has been described. This report is to highlight another local side effect of sublingual immunotherapy which has been observed in 3 of our patients. This is pigmentation of the gums which can occur anytime during the course of the immunotherapy. It resolves on stopping the immunotherapy and is likely due to a local inflammatory process occurring in the gums of these children. There is no associated pain or itching with the pigmentation. It can persist as long as the child is on the immunotherapy.
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CD137 ligand signalling induces differentiation of primary acute myeloid leukaemia cells.
Br. J. Haematol.
PUBLISHED: 01-15-2014
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CD137 ligand (CD137L), a member of the tumour necrosis factor family, is expressed as a cell surface molecule. Engagement of CD137L on haematopoietic progenitor cells induces monocytic differentiation, and in peripheral monocytes CD137L signalling promotes differentiation to mature dendritic cells. We hypothesized that CD137L signalling would also induce differentiation in transformed myeloid cells. Here we show that recombinant CD137 protein, which crosslinks CD137L and initiates reverse CD137L signalling in myeloid cells, induces morphological changes (adherence, spreading), loss of progenitor markers (CD117), expression of maturation markers (CD11b, CD13) and secretion of cytokines that are indicative of myeloid differentiation. Under the influence of CD137L signalling, acute myeloid leukaemia (AML) cells acquired expression of co-stimulatory molecules (CD80, CD86, CD40), the dendritic cell marker CD83 and dendritic cell activities, enabling them to stimulate T cells. CD137L signalling induced differentiation in 71% (15 of 21) of AML samples, irrespective of French-American-British classification and CD137L expression level. However, the type of response varied with the AML subtype and patient sample. In summary, this study demonstrated that CD137L signalling induced differentiation in malignant cells of AML patients, and suggests that it may be worthwhile to investigate treatment with recombinant CD137 protein as a potential novel therapeutic approach for AML.
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p53 haploinsufficiency and functional abnormalities in multiple myeloma.
Leukemia
PUBLISHED: 01-07-2014
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Hemizygous deletion of 17p13, which harbors the TP53 gene, has been identified in >10% of newly diagnosed multiple myeloma (MM) patients and is associated with poor prognosis. To date, there is no conclusive evidence that TP53 is the critical gene. Furthermore, the functional effect of TP53 haploinsufficiency is not well characterized. By utilizing human myeloma cell lines, we showed that TP53 hemizygous loss was associated with decreased basal expression level with a partially or severely inactivated p53 response upon genotoxic and non-genotoxic stress. The pathway deficiency was manifested as defective p53 transcriptional activities, together with significant resistance to apoptosis. In some cases with p53 WT/- and no p53 protein expression, the remaining allele was silenced by promoter hypermethylation. We also developed a p53 target gene signature to summarize the complexity of the p53 pathway abnormalities in MM and showed that it is strongly associated with genomic complexity and patient survival. In conclusion, this study identified TP53 as the critical gene located in 17p13, and revealed its haploinsufficiency properties in MM. Furthermore, we have elucidated that multiple mechanisms can deregulate the p53 functions and that this has important prognostic impact in MM.
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Individual and area-level socioeconomic status and their association with depression amongst community-dwelling elderly in Singapore.
Aging Ment Health
PUBLISHED: 01-07-2014
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Neighborhood socioeconomic status (SES) can be associated with depression. We aimed to assess prevalence of depression amongst community-dwelling elderly in a multiethnic, urban, low-SES, Asian neighborhood, comparing against a higher SES neighborhood.
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A new esthetic fiber-reinforced polymer composite resin archwire: a comparative atomic force microscope (AFM) and field-emission scanning electron microscope (FESEM) study.
Prog Orthod
PUBLISHED: 01-02-2014
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Fiber-reinforced polymer composite (FRPC) archwires could provide an esthetic solution to conventional orthodontic archwires. This study was carried out with the following aims: (1) to compare the sliding friction of FRPC archwire with nickel titanium archwire using various archwire-bracket combinations and (2) to determine the correlation between surface roughness and friction of the FRPC and NiTi archwires.
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Liposomal codelivery of a synergistic combination of bioactive lipids in the treatment of acute myeloid leukemia.
Nanomedicine (Lond)
PUBLISHED: 12-03-2013
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Aim: The aim of this work was to develop a liposomal formulation to facilitate delivery of a synergistic safingol/C2-ceramide combination in the treatment of acute myeloid leukemia (AML). Materials & methods: Liposomes were prepared using the extrusion method and the bioactive lipids were encapsulated passively. Drug concentrations were determined by liquid chromatography tandem mass spectrometry. Antileukemic activity was evaluated using human leukemic cell lines, patient samples and U937 leukemic xenograft models. Results: A stable liposome formulation was developed to coencapsulate safingol and C2-ceramide at 1:1 molar ratio with >90% encapsulation efficiency. The liposomal safingol/C2-ceramide was effective in AML cell lines, patient samples and murine xenograft models of AML, compared with liposomal safingol or liposomal C2-ceramide alone despite a dose reduction of 33%. Conclusion: Our study provided proof-of-concept evidence to deliver synergistic combination of bioactive lipid to achieve complete remission in AML. Original submitted: 27 February 2013; Revised submitted: 25 June 2013.
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Towards biocompatible nano/microscale machines: self-propelled catalytic nanomotors not exhibiting acute toxicity.
Nanoscale
PUBLISHED: 11-26-2013
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Recent advances in nanotechnology have led to the evolution of self-propelled, artificial nano/microjet motors. These intelligent devices are considered to be the next generation self-powered drug delivery system in the field of biomedical applications. While many studies have strived to further improve the various properties of these devices such as their efficiency, performance and power, little attention has been paid to the actual biocompatibility of nanojets in vivo. In this paper, we will present for the first time the investigation of the toxicity effects of nanojets on the viability of human lung epithelial cells (A549 cells). From the 24 h and 48 h post-exposure studies, it is clearly shown that the nanojets we used in our work has negligible influence on the cell viability across all the concentrations tested. As such, the toxicity profile of our nanojets have been shown to be neither dose- nor time-dependent. This is strongly indicative of the benign nature of our nanojets, which is of paramount significance as it is the first step towards the applications of nano/micromotors in real-world practical medical devices.
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Propagation of Human Corneal Endothelial Cells ? A Novel Dual Media Approach.
Cell Transplant
PUBLISHED: 11-26-2013
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Corneal endothelium?associated corneal blindness is the most common indication for corneal transplantation. Restorative corneal transplant surgery is the only option to reverse the blindness, but global shortage of donor material remains an issue. There are immense clinical interests in the development of alternative treatment strategies to alleviate current reliance on donor materials. For such endeavors, ex vivo propagation of human corneal endothelial cells (CECs) is required but current methodology lacks consistency with expanded CECs losing cellular morphology to a mesenchymal?like transformation. In this study, we describe a novel dual media culture approach for the in vitro expansion of primary human CECs. Initial characterization included analysis of growth dynamics of CECs grown in either proliferative (M4) or maintenance (M5) medium. Subsequent comparisons were performed on isolated CECs cultured in M4?alone against cells expanded using the dual media approach. Further characterizations were performed using immunocytochemistry, quantitative real?time PCR and gene expression microarray. At the third passage, results showed that human CECs propagated using the dual media approach were homogeneous in appearance, retained their unique polygonal cellular morphology, and expressed higher levels of corneal endothelium?associated markers in comparison to CECs cultured in M4?alone, which were heterogeneous and fibroblastic in appearance. Finally, for CECs cultured using the dual media approach, global gene expression and pathway analysis between confluent CECs before and after seven days exposure to M5 exhibited differential gene expression associated predominately with cell proliferation and wound healing. These findings showed that the propagation of primary human CECs using the novel dual media approach presented in this study is a consistent method to obtain bona fide human CECs. This in turn will elicit greater confidence in facilitating downstream development of alternative corneal endothelium replacement using tissue?engineered graft materials or cell injection therapy.
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Immunoprevalence and Immunodominance of HLA-Cw*0801-Restricted T Cell Response Targeting the Hepatitis B Virus Envelope Transmembrane Region.
J. Virol.
PUBLISHED: 11-13-2013
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HLA-C-restricted T cells have been shown to play an important role in HIV control, but their impact on protection or pathogenesis in other viral infections remains elusive. Here, we characterized the hierarchy of HLA class I-restricted hepatitis B virus (HBV) epitopes targeted by CD8 T cells in HBV-infected subjects. The frequency of CD8 T cells specific for a panel of 18 HBV epitopes (restricted by HLA-A?0201/03/07 [hereinafter HLA-A0201/03/07], -A1101, -A2402/07, -B5801, -B4001, -B1301, and -Cw0801) was quantified in a total of 59 subjects who resolved HBV infection. We found that the HLA-Cw0801-restricted epitope comprised of Env residues 171 to 180 (Env171-180) is immunoprevalent in the Southeast Asian subjects (10/17 HLA-Cw0801-positive subjects) and immunodominant in the majority of HLA-Cw0801-positive subjects able to control HBV infection. HLA-Cw0801-restricted Env171-180-specific CD8 T cells recognized endogenously produced HBV surface antigen (HBsAg) and tolerated amino acid variations within the epitope detected in HBV genotypes B and C. In conclusion, we demonstrate that the HLA-Cw0801-restricted Env171-180 T cell response is an important component of the HBV-specific adaptive T cell immunity in Asians infected with HBV. Thus, HLA-C restricted T cells might play an important role in various viral infections.
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T Lymphocytes Expressing a CD16 Signaling Receptor Exert Antibody-Dependent Cancer Cell Killing.
Cancer Res.
PUBLISHED: 11-06-2013
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To expand applications for T-cell-based immunotherapy in cancer, we designed a receptor that binds the Fc portion of human immunoglobulins and delivers activation signals. The construct included the high-affinity CD16 (FCGR3A) V158 variant, CD8? hinge, and transmembrane domains, along with signaling domains from CD3? and 4-1BB (TNFRSF9), forming a chimeric receptor termed CD16V-BB-?. After retrovirus-mediated expression in human T cells, CD16V-BB-? bound humanized antibodies with higher affinity than a control receptor containing the more common F158 variant. Engagement of CD16V-BB-? provoked T-cell activation, exocytosis of lytic granules, and sustained proliferation, with a mean cell recovery after 4-week coculture with Daudi lymphoma cells and rituximab of nearly 70-fold relative to input cells. In contrast, unbound antibody alone produced no effect. CD16V-BB-? T cells specifically killed lymphoma cells and primary chronic lymphocytic leukemia cells in combination with rituximab at a low effector:target ratio, even when assayed on mesenchymal cells. Trastuzumab triggered CD16V-BB-?-mediated killing of HER2 (ERBB2)(+) breast and gastric cancer cells; similar results were obtained with an anti-GD2 antibody in neuroblastoma and osteosarcoma cells. Furthermore, coadministration of CD16V-BB-? T cells with immunotherapeutic antibodies exerted considerable antitumor activity in vivo. Signaling mediated by 4-1BB-CD3? induced higher T-cell activation, proliferation, and cytotoxicity than CD3? or Fc?RI?, and the receptor was expressed effectively after mRNA electroporation without viral vectors, facilitating clinical translation. Our results offer preclinical proof of concept for CD16V-BB-? as a universal, next-generation chimeric receptor with the potential to augment the efficacy of antibody therapies for cancer. Cancer Res; 74(1); 1-11. ©2013 AACR.
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Management of multiple myeloma in Asia: resource-stratified guidelines.
Lancet Oncol.
PUBLISHED: 11-02-2013
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Treatment of multiple myeloma has undergone substantial developments in the past 10 years. The introduction of novel drugs has changed the treatment of the disease and substantially improved survival outcomes. Clinical practice guidelines based on evidence have been developed to provide recommendations on standard treatment approaches. However, the guidelines do not take into account resource limitations encountered by developing countries. The huge disparities in economy, health-care infrastructure, and access to novel drugs in Asian countries hinder the delivery of optimum care to every patient with multiple myeloma in Asia. In this Review we outline the guidelines that correspond with different levels of health-care resources and expertise, with the aim to unify diagnostic and therapeutic guidelines and help with the design of future studies in Asia.
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Extranodal natural killer/T-cell lymphoma involving the gastrointestinal tract: analysis of clinical features and outcomes from the Asia Lymphoma Study Group.
J Hematol Oncol
PUBLISHED: 10-31-2013
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The gastrointestinal (GI) tract is one of the most common extranasal sites in extranodal NK/T-cell lymphoma (ENKTL). However, data regarding ENKTL involving the GI tract are relatively scarce. Thus, we performed a multicenter, multinational retrospective study to analyze clinical features and treatment outcomes of ENKTL involving the GI tract.
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Randomized Clinical Trial of Cutting Balloon Angioplasty versus High-Pressure Balloon Angioplasty in Hemodialysis Arteriovenous Fistula Stenoses Resistant to Conventional Balloon Angioplasty.
J Vasc Interv Radiol
PUBLISHED: 10-12-2013
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To compare the efficacy and safety of cutting balloon angioplasty (CBA) versus high-pressure balloon angioplasty (HPBA) for the treatment of hemodialysis autogenous fistula stenoses resistant to conventional percutaneous transluminal angioplasty (PTA).
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Clonogenic multiple myeloma cells have shared stemness signature assocuated with patient survival.
Oncotarget
PUBLISHED: 08-30-2013
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Multiple myeloma is the abnormal clonal expansion of post germinal B cells in the bone marrow. It was previously reported that clonogenic myeloma cells are CD138-. Human MM cell lines RPMI8226 and NCI H929 contained 2-5% of CD138- population. In this study, we showed that CD138- cells have increased ALDH1 activity, a hallmark of normal and neoplastic stem cells. CD138-ALDH+ cells were more clonogenic than CD138+ALDH- cells and only CD138- cells differentiated into CD138+ populations. In vivo tumor initiation and clonogenic potentials of the CD138- population was confirmed using NOG mice. We derived a gene expression signature from functionally validated and enriched CD138- clonogenic population from MM cell lines and validated these in patient samples. This data showed that CD138- cells had an enriched expression of genes that are expressed in normal and malignant stem cells. Differentially expressed genes included components of the polycomb repressor complex (PRC) and their targets. Inhibition of PRC by DZNep showed differential effect on CD138- and CD138+ populations. The stemness signature derived from clonogenic CD138- cells overlap significantly with signatures of common progenitor cells, hematopoietic stem cells, and Leukemic stem cells and is associated with poorer survival in different clinical datasets.
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New drugs and novel mechanisms of action in multiple myeloma in 2013: a report from the International Myeloma Working Group (IMWG).
Leukemia
PUBLISHED: 08-27-2013
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Treatment in medical oncology is gradually shifting from the use of nonspecific chemotherapeutic agents toward an era of novel targeted therapy in which drugs and their combinations target specific aspects of the biology of tumor cells. Multiple myeloma (MM) has become one of the best examples in this regard, reflected in the identification of new pathogenic mechanisms, together with the development of novel drugs that are being explored from the preclinical setting to the early phases of clinical development. We review the biological rationale for the use of the most important new agents for treating MM and summarize their clinical activity in an increasingly busy field. First, we discuss data from already approved and active agents (including second- and third-generation proteasome inhibitors (PIs), immunomodulatory agents and alkylators). Next, we focus on agents with novel mechanisms of action, such as monoclonal antibodies (MoAbs), cell cycle-specific drugs, deacetylase inhibitors, agents acting on the unfolded protein response, signaling transduction pathway inhibitors and kinase inhibitors. Among this plethora of new agents or mechanisms, some are specially promising: anti-CD38 MoAb, such as daratumumab, are the first antibodies with clinical activity as single agents in MM. Moreover, the kinesin spindle protein inhibitor Arry-520 is effective in monotherapy as well as in combination with dexamethasone in heavily pretreated patients. Immunotherapy against MM is also being explored, and probably the most attractive example of this approach is the combination of the anti-CS1 MoAb elotuzumab with lenalidomide and dexamethasone, which has produced exciting results in the relapsed/refractory setting.Leukemia advance online publication, 20 December 2013; doi:10.1038/leu.2013.350.
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ELABELA: A Hormone Essential for Heart Development Signals via the Apelin Receptor.
Dev. Cell
PUBLISHED: 08-09-2013
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We report here the discovery and characterization of a gene, ELABELA (ELA), encoding a conserved hormone of 32 amino acids. Present in human embryonic stem cells, ELA is expressed at the onset of zebrafish zygotic transcription and is ubiquitous in the naive ectodermal cells of the embryo. Using zinc-finger-nuclease-mediated gene inactivation in zebrafish, we created an allelic series of ela mutants. ela null embryos have impaired endoderm differentiation potential marked by reduced gata5 and sox17 expression. Loss of Ela causes embryos to develop with a rudimentary heart or no heart at all, surprisingly phenocopying the loss of the apelin receptor (aplnr), which we show serves as Elas cognate G protein-coupled receptor. Our results reveal the existence of a peptide hormone, ELA, which, together with APLNR, forms an essential signaling axis for early cardiovascular development.
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Plasma membrane proteomics identifies biomarkers associated with MMSET overexpression in T(4;14) multiple myeloma.
Oncotarget
PUBLISHED: 08-01-2013
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Multiple myeloma (MM) is characterized by recurrent chromosomal translocations. MMSET, identified by its fusion to the IgH locus in t(4;14) MM, is universally overexpressed in t(4;14) MM. In order to identify cell surface biomarkers associated with t(4;14) MM for small molecule or antibody based therapies, we knocked down MMSET expression with shRNA and generated a cell line pair from KMS11, a t(4;14) MM cell line. We used quantitative mass spectrometry to identify plasma membrane proteins associated with MMSET overexpression. Using this approach, 50 cell surface proteins were identified as differentially expressed between KMS11 and KMS11/shMMSET. Western blot and flow cytometry analysis indicated SLAMF7 was over-expressed in t(4;14) MM cell lines and down-regulated by MMSET shRNAs. SLAMF7 expression was also confirmed in primary t(4;14) MM samples by flow cytometry analysis. Quantitative RT-PCR and ChIP analysis indicated MMSET might regulate the transcription level of SLAMF7 and be an important functional element for SLAMF7 promoter activity. Furthermore, SLAMF7 shRNA could induce G1 arrest or apoptosis and reduce clonogenetic capacity in t(4;14) MM cells. Overall, these results illustrated SLAMF7 might be a novel cell surface protein associated with t(4;14) MM. It is potential to develop t(4;14) MM targeted therapy by SLAMF7 antibody mediated drug delivery.
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B Lymphocytes in obesity-related adipose tissue inflammation and insulin resistance.
Cell. Mol. Life Sci.
PUBLISHED: 07-11-2013
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Obesity-related insulin resistance is a chronic inflammatory condition that often gives rise to type 2 diabetes (T2D). Much evidence supports a role for pro-inflammatory T cells and macrophages in promoting local inflammation in tissues such as visceral adipose tissue (VAT) leading to insulin resistance. More recently, B cells have emerged as an additional critical player in orchestrating these processes. B cells infiltrate VAT and display functional and phenotypic changes in response to diet-induced obesity. B cells contribute to insulin resistance by presenting antigens to T cells, secreting inflammatory cytokines, and producing pathogenic antibodies. B cell manipulation represents a novel approach to the treatment of obesity-related insulin resistance and potentially to the prevention of T2D. This review summarizes the roles of B cells in governing VAT inflammation and the mechanisms by which these cells contribute to altered glucose homeostasis in insulin resistance.
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Oncogenic roles of PRL-3 in FLT3-ITD induced acute myeloid leukaemia.
EMBO Mol Med
PUBLISHED: 06-18-2013
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FLT3-ITD mutations are prevalent mutations in acute myeloid leukaemia (AML). PRL-3, a metastasis-associated phosphatase, is a downstream target of FLT3-ITD. This study investigates the regulation and function of PRL-3 in leukaemia cell lines and AML patients associated with FLT3-ITD mutations. PRL-3 expression is upregulated by the FLT3-STAT5 signalling pathway in leukaemia cells, leading an activation of AP-1 transcription factors via ERK and JNK pathways. PRL-3-depleted AML cells showed a significant decrease in cell growth. Clinically, high PRL-3 mRNA expression was associated with FLT3-ITD mutations in four independent AML datasets with 1158 patients. Multivariable Cox-regression analysis on our Cohort 1 with 221 patients identified PRL-3 as a novel prognostic marker independent of other clinical parameters. Kaplan-Meier analysis showed high PRL-3 mRNA expression was significantly associated with poorer survival among 491 patients with normal karyotype. Targeting PRL-3 reversed the oncogenic effects in FLT3-ITD AML models in vitro and in vivo. Herein, we suggest that PRL-3 could serve as a prognostic marker to predict poorer survival and as a promising novel therapeutic target for AML patients.
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Identification of cell surface markers glypican-4 and CD200 that differentiate human corneal endothelium from stromal fibroblasts.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 06-08-2013
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There is a lack of definitive cell surface markers to differentiate cultured human corneal endothelial cells (HCECs) from stromal fibroblasts, which could contaminate HCEC cultures. The aim of our study is to discover cell surface antigens on HCECs that can be used to identify and purify HCECs from stromal fibroblasts.
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Direct costs associated with febrile neutropenia in inpatients with hematological diseases in Singapore.
Support Care Cancer
PUBLISHED: 05-27-2013
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This prospective cohort study aims to investigate the direct hospitalization costs incurred during febrile neutropenia (FN) in inpatients with underlying hematological conditions and also to elucidate the factors associated with a high cost of managing febrile neutropenia.
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Hepatitis B virus reactivation in B-cell lymphoma patients treated with rituximab: analysis from the Asia Lymphoma Study Group.
Eur. J. Cancer
PUBLISHED: 05-24-2013
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Hepatitis B virus (HBV) reactivation is increasing, as rituximab has become widely used for B-cell lymphoma. Thus, prevention and management of HBV reactivation are important in HBV-endemic areas.
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Metastasis-associated PRL-3 induces EGFR activation and addiction in cancer cells.
J. Clin. Invest.
PUBLISHED: 05-10-2013
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Metastasis-associated phosphatase of regenerating liver-3 (PRL-3) has pleiotropic effects in driving cancer progression, yet the signaling mechanisms of PRL-3 are still not fully understood. Here, we provide evidence for PRL-3-induced hyperactivation of EGFR and its downstream signaling cascades in multiple human cancer cell lines. Mechanistically, PRL-3-induced activation of EGFR was attributed primarily to transcriptional downregulation of protein tyrosine phosphatase 1B (PTP1B), an inhibitory phosphatase for EGFR. Functionally, PRL-3-induced hyperactivation of EGFR correlated with increased cell growth, promigratory characteristics, and tumorigenicity. Moreover, PRL-3 induced cellular addiction to EGFR signaling, as evidenced by the pronounced reversion of these oncogenic attributes upon EGFR-specific inhibition. Of clinical significance, we verified elevated PRL-3 expression as a predictive marker for favorable therapeutic response in a heterogeneous colorectal cancer (CRC) patient cohort treated with the clinically approved anti-EGFR antibody cetuximab. The identification of PRL-3-driven EGFR hyperactivation and consequential addiction to EGFR signaling opens new avenues for inhibiting PRL-3-driven cancer progression. We propose that elevated PRL-3 expression is an important clinical predictive biomarker for favorable anti-EGFR cancer therapy.
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Deregulated MIR335 that targets MAPK1 is implicated in poor outcome of paediatric acute lymphoblastic leukaemia.
Br. J. Haematol.
PUBLISHED: 05-09-2013
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Acute lymphoblastic leukaemia (ALL) is the most common paediatric malignancy. Although 90% of patients are now long-term survivors, the remaining 10% have poor outcome predominantly due to drug resistance. In this study, we carried out genome-wide microRNA (miRNA) microarray analysis on diagnostic bone marrow samples to determine miRNA expression profiles associated with poor outcome in ALL. A reduced expression of MIR335 was identified as the most significant miRNA abnormality associated with poor outcome. It is well known that glucocorticoid (GC) resistance is one of the major reasons contributing to poor outcome. We show that exogenous expression of MIR335 in ALL cells increases sensitization to prednisolone-mediated apoptosis. Moreover, we demonstrate that MAPK1 is a novel target of MIR335, and that MEK/ERK inhibitor treatment enhanced prednisolone-induced cell death through the activation of BIM (BCL2L11). These results provide a possible underlying molecular mechanism to explain the association between reduced MIR335 with poor clinical outcome, and suggest that approaches to re-introduce MIR335 expression or override MAPK1 activity may offer promising therapeutic strategies in the treatment of ALL.
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Sox transcription factors require selective interactions with Oct4 and specific transactivation functions to mediate reprogramming.
Stem Cells
PUBLISHED: 05-03-2013
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The unique ability of Sox2 to cooperate with Oct4 at selective binding sites in the genome is critical for reprogramming somatic cells into induced pluripotent stem cells (iPSCs). We have recently demonstrated that Sox17 can be converted into a reprogramming factor by alteration of a single amino-acid (Sox17EK) within its DNA binding HMG domain. Here we expanded this study by introducing analogous mutations to 10 other Sox proteins and interrogated the role of N-and C-termini on the reprogramming efficiency. We found that point-mutated Sox7 and Sox17 can convert human and mouse fibroblasts into iPSCs, but Sox4, Sox5, Sox6, Sox8, Sox9, Sox11, Sox12, Sox13 and Sox18 cannot. Next we studied regions outside the HMG domain and found that the C-terminal transactivation domain of Sox17 and Sox7 enhances the potency of Sox2 in iPSC assays and confers weak reprogramming potential to the otherwise inactive Sox4EK and Sox18EK proteins. These results suggest that the glutamate (E) to lysine (K) mutation in the HMG domain is necessary, but insufficient to swap the function of Sox factors. Moreover, the HMG domain alone fused to the VP16 transactivation domain is able to induce reprogramming, albeit at low efficiency. By molecular dissection of the C-terminus of Sox17 we found that the ?-catenin interaction region contributes to the enhanced reprogramming efficiency of Sox17EK. To mechanistically understand the enhanced reprogramming potential of Sox17EK we analysed ChIP-sequencing and expression data and identified a subset of candidate genes specifically regulated by Sox17EK and not by Sox2. Stem Cells 2013.
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Recurrent chromosome abnormalities define nonoverlapping unique subgroups of tumors in patients with chronic lymphocytic leukemia and known karyotypic abnormalities.
Clin Lymphoma Myeloma Leuk
PUBLISHED: 05-02-2013
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A major conclusion drawn from the accumulated cytogenetic data on solid tumors and some hematologic malignancies is that tumors progress by the acquisition of chromosomal changes, as reflected by more aggressive tumors containing a larger number of chromosomal abnormalities. An additional observation is that some chromosomal changes appear early in the disease progression, and some others appear late.
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Intestinal torsion causing chylous ascites: a rare occurrence.
Singapore Med J
PUBLISHED: 04-30-2013
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Intestinal torsion and chylous ascites are very rarely associated. We present the case of a 19-year-old man who presented with acute abdomen. Computed tomography of his abdomen showed features suggestive of intestinal torsion. Chylous ascites was incidentally discovered on exploratory laparotomy. The chylous fluid was drained, the small bowel detorted and the coloduodenal adhesion band taken down. The patients retroperitoneum was explored to exclude occult masses and malformations of the lymphatics. Post surgery, the patient recovered uneventfully. In this case, we postulate that intestinal malrotation had caused the obstruction of the lymphatic flow from the mesenteric lymphatic channels, leading to the exudation of chyle, which then resulted in the accumulation of chylous fluid in the peritoneal cavity. It is important to exclude the more common causes of atraumatic chylous ascites, such as enlarged retroperitoneal lymph nodes or lymphatic malformations.
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Belinostat and panobinostat (HDACI): in vitro and in vivo studies in thyroid cancer.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 04-24-2013
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Advanced thyroid cancer responds poorly to most therapies. New therapies and combinations are needed. The aim of this study was to examine both in vitro and in vivo activity of two relatively new histone deacetylase inhibitors (HDACIs), belinostat and panobinostat, and a variety of tyrosine kinase inhibitors (TKIs) against a panel of nine human thyroid cancer cell lines.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.