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1.
Phys Rev Lett ; 132(13): 131001, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38613296

ABSTRACT

We searched for antideuterons (d[over ¯]'s) in the 4.7×10^{9} cosmic-ray events observed during the BESS-Polar II flight at solar minimum in 2007-2008 but found no candidates. The resulting 95% C.L. upper limit on the d[over ¯] flux is 6.7×10^{-5} (m^{2} s sr GeV/n)^{-1} in an energy range from 0.163 to 1.100 GeV/n. The result has improved by more than a factor of 14 from the upper limit of BESS97, which had a potential comparable to that of BESS-Polar II in the search for cosmic-origin d[over ¯]'s and was conducted during the former solar minimum. The upper limit of d[over ¯] flux from BESS-Polar II is the first result achieving the sensitivity to constrain the latest theoretical predictions.

2.
Oncogene ; 36(49): 6793-6804, 2017 12 07.
Article in English | MEDLINE | ID: mdl-28846112

ABSTRACT

RNA polymerase III (Pol III) transcribes medium-sized non-coding RNAs (collectively termed Pol III genes). Emerging diverse roles of Pol III genes suggest that individual Pol III genes are exquisitely regulated by transcription and epigenetic factors. Here we report global Pol III expression/methylation profiles and molecular mechanisms of Pol III regulation that have not been as extensively studied, using nc886 as a representative Pol III gene. In a human mammary epithelial cell system that recapitulates early breast tumorigenesis, the fraction of actively transcribed Pol III genes increases reaching a plateau during immortalization. Hyper-methylation of Pol III genes inhibits Pol III binding to DNA via inducing repressed chromatin and is a determinant for the Pol III repertoire. When Pol III genes are hypo-methylated, MYC amplifies their transcription, regardless of its recognition DNA motif. Thus, Pol III expression during tumorigenesis is delineated by methylation and magnified by MYC.


Subject(s)
Breast/metabolism , Cell Transformation, Neoplastic/genetics , Epigenesis, Genetic , RNA Polymerase III/metabolism , Transcription, Genetic , Breast/cytology , Cells, Cultured , Chromatin/genetics , Chromatin/metabolism , DNA/genetics , DNA/metabolism , DNA Methylation , Epithelial Cells/metabolism , Humans , Protein Binding , Proto-Oncogene Proteins c-myc/genetics , RNA, Untranslated/genetics
4.
Arthritis Rheumatol ; 69(5): 1054-1066, 2017 05.
Article in English | MEDLINE | ID: mdl-28029757

ABSTRACT

OBJECTIVE: To identify risk alleles relevant to the causal and biologic mechanisms of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: A genome-wide association study and subsequent replication study were conducted in a total cohort of 1,986 cases of AAV (patients with granulomatosis with polyangiitis [Wegener's] [GPA] or microscopic polyangiitis [MPA]) and 4,723 healthy controls. Meta-analysis of these data sets and functional annotation of identified risk loci were performed, and candidate disease variants with unknown functional effects were investigated for their impact on gene expression and/or protein function. RESULTS: Among the genome-wide significant associations identified, the largest effect on risk of AAV came from the single-nucleotide polymorphism variants rs141530233 and rs1042169 at the HLA-DPB1 locus (odds ratio [OR] 2.99 and OR 2.82, respectively) which, together with a third variant, rs386699872, constitute a triallelic risk haplotype associated with reduced expression of the HLA-DPB1 gene and HLA-DP protein in B cells and monocytes and with increased frequency of complementary proteinase 3 (PR3)-reactive T cells relative to that in carriers of the protective haplotype. Significant associations were also observed at the SERPINA1 and PTPN22 loci, the peak signals arising from functionally relevant missense variants, and at PRTN3, in which the top-scoring variant correlated with increased PRTN3 expression in neutrophils. Effects of individual loci on AAV risk differed between patients with GPA and those with MPA or between patients with PR3-ANCAs and those with myeloperoxidase-ANCAs, but the collective population attributable fraction for these variants was substantive, at 77%. CONCLUSION: This study reveals the association of susceptibility to GPA and MPA with functional gene variants that explain much of the genetic etiology of AAV, could influence and possibly be predictors of the clinical presentation, and appear to alter immune cell proteins and responses likely to be key factors in the pathogenesis of AAV.


Subject(s)
Granulomatosis with Polyangiitis/genetics , HLA-DP beta-Chains/genetics , Microscopic Polyangiitis/genetics , Myeloblastin/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 22/genetics , T-Lymphocytes/metabolism , alpha 1-Antitrypsin/genetics , Adult , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/genetics , Autoantigens/immunology , B-Lymphocytes/metabolism , Case-Control Studies , Female , Gene Expression , Genetic Predisposition to Disease , Genome-Wide Association Study , HLA-DP Antigens/metabolism , HLA-DP beta-Chains/metabolism , Haplotypes , Humans , Male , Middle Aged , Monocytes/metabolism , Myeloblastin/immunology , Neutrophils/metabolism , Odds Ratio , Peroxidase/immunology , Polymorphism, Single Nucleotide , T-Lymphocytes/immunology
5.
Int J Lab Hematol ; 38(4): 444-53, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27321126

ABSTRACT

INTRODUCTION: This study investigates the benefits of using multiplex reverse transcriptase-PCR (RT-PCR) in addition to standard karyotyping during the initial evaluation of acute leukemia. METHODS: A total of 1114 consecutive specimens from patients with acute leukemia were tested using a commercial multiplex RT-PCR kit (HemaVision, DNA Diagnostic). NPM1 and CEBPA mutations were selectively tested in acute myeloid leukemia (AML) patients with multiplex RT-PCR negativity. RESULTS: In specimens with optimal cytogenetics, the frequency of recurrent translocations was 31.3%, and cryptic translocations were detected in 2.1% of samples. The concordance rate between karyotyping and multiplex RT-PCR was 97.5%. In addition to the established functions, we demonstrated the additional benefits of multiplex RT-PCR, including successful molecular characterization, even in cytogenetically suboptimal specimens (5.7%); detection of submicroscopic aberrations (1.0%); detection of rare but potentially significant translocations or variants (2.5%); selection of AML candidates for mutation analysis (68.3%); and finally exclusion of recurrent translocations in patients with acute lymphoblastic leukemia or mixed phenotype acute leukemia (22.5%). CONCLUSION: We reconfirmed the accuracy and reliability of multiplex RT-PCR for diagnosing acute leukemia and demonstrated additional advantages of this system for the initial evaluation of acute leukemia. Thus, multiplex RT-PCR is worth considering in diagnostic testing of acute leukemias.


Subject(s)
Genetic Testing/methods , Leukemia/diagnosis , Reverse Transcriptase Polymerase Chain Reaction , Acute Disease , CCAAT-Enhancer-Binding Proteins/genetics , Humans , Leukemia/genetics , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/genetics , Mutation , Nuclear Proteins/genetics , Nucleophosmin , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Reproducibility of Results , Translocation, Genetic
6.
Astrophys J ; 822(2)2016 May 10.
Article in English | MEDLINE | ID: mdl-32713958

ABSTRACT

The BESS-Polar Collaboration measured the energy spectra of cosmic-ray protons and helium during two long-duration balloon flights over Antarctica in December 2004 and December 2007, at substantially different levels of solar modulation. Proton and helium spectra probe the origin and propagation history of cosmic rays in the galaxy, and are essential to calculations of the expected spectra of cosmic-ray antiprotons, positrons, and electrons from interactions of primary cosmic-ray nuclei with the interstellar gas, and to calculations of atmospheric muons and neutrinos. We report absolute spectra at the top of the atmosphere for cosmic-ray protons in the kinetic energy range 0.2-160 GeV and helium nuclei 0.15-80 GeV/nucleon. The corresponding magnetic rigidity ranges are 0.6-160 GV for protons and 1.1-160 GV for helium. These spectra are compared to measurements from previous BESS flights and from ATIC-2, PAMELA, and AMS-02. We also report the ratio of the proton and helium fluxes from 1.1 GV to 160 GV and compare to ratios from PAMELA and AMS-02.

7.
Int J Lab Hematol ; 36(5): 571-9, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24612538

ABSTRACT

INTRODUCTION: The rearrangement of the mixed-lineage leukemia (MLL) gene occurs through translocations and insertions involving a variety of partner chromosome genes. However, there are few studies on aberrant MLL signal patterns such as concurrent 3' MLL deletion. METHODS: A total of 84 patients with acute leukemia (AL) who had MLL rearrangements detected by florescence in situ hybridization (FISH) were enrolled in the study. The distribution of MLL fusion partner genes was analyzed, and aberrant MLL signals were evaluated. RESULTS: Seventy-seven (91.7%) patients had MLL rearrangements, involving previously described translocation partner genes (TPGs). Among these TPGs, the frequencies of MLLT3, AFF1, MLLT4, and ELL were 29.8%, 17.9%, 15.5%, and 13.1%, respectively. A high frequency of MLLT4 in our study was due to the high proportion of acute myeloid leukemia cases in pediatric and adult patients. Aberrant MLL signals were found in 18 patients: 11 (61.1%) with 3' MLL signal loss and 7 with 3' MLL signal gain. All cases with 3' MLL signal gain were due to an extra derivative partner chromosome. The median overall survival period of patients with 3' MLL gain was shorter than that in patients without aberrant MLL signal patterns. CONCLUSION: Aberrant MLL signals were frequently detected by FISH analysis. The 3' MLL gain was associated with poor prognosis in patients with AL. Therefore, it is important to detect aberrant MLL signal patterns using FISH analysis.


Subject(s)
3' Flanking Region , Gene Rearrangement , Leukemia, Biphenotypic, Acute/genetics , Leukemia, Myeloid, Acute/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , Adolescent , Adult , Child , Child, Preschool , Female , Histone-Lysine N-Methyltransferase , Humans , In Situ Hybridization, Fluorescence , Infant , Infant, Newborn , Leukemia, Biphenotypic, Acute/diagnosis , Leukemia, Biphenotypic, Acute/mortality , Leukemia, Biphenotypic, Acute/pathology , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/mortality , Leukemia, Myeloid, Acute/pathology , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Analysis
9.
Plant Dis ; 98(1): 164, 2014 Jan.
Article in English | MEDLINE | ID: mdl-30708591

ABSTRACT

Cherry necrotic rusty mottle virus (CNRMV), an unassigned member in the family Betaflexiviridae, has been reported in sweet cherry in North America, Europe, New Zealand, Japan, China, and Chile. The virus causes brown, angular necrotic spots, shot holes on the leaves, gum blisters, and necrosis of the bark in several cultivars (1). During the 2012 growing season, 154 sweet cherry trees were tested for the presence of CNRMV by RT-PCR. Samples were randomly collected from 11 orchards located in Gyeonggi and Gyeongsang provinces in Korea. RNA was extracted from leaves using the NucliSENS easyMAG system (bioMérieux, Boxtel, The Netherlands). The primer pair CGRMV1/2 (2) was used to amplify the coat protein region of CNRMV. Although none of the collected samples showed any notable symptoms, CNRMV PCR products of the expected size (949 bp) were obtained from three sweet cherry samples from one orchard in Gyeonggi province. The PCR products were cloned into a pGEM-T easy vector (Promega, Madison, WI) and sequenced. BLAST analyses of the three Korean sequences obtained (GenBank Accession Nos. AB822635, AB822636, and AB822637) showed 97% nucleotide sequence identity with a flowering cherry isolate from Japan (EU188439), and shared 98.8 to 99.6% nucleotide and 99.6 to 100% amino acid similarities to each other. The CNRMV positive samples were also tested for Apple chlorotic leaf spot virus (ACLSV), Cherry mottle leaf virus (CMLV), Cherry rasp leaf virus (CRLV), Cherry leafroll virus (CLRV), Cherry virus A (CVA), Little cherry virus 1 (LChV-1), Prune dwarf virus (PDV), and Prunus necrotic ringspot virus (PNRSV) by RT-PCR. One of the three CNRMV-positive samples was also infected with CVA. To confirm CNRMV infection by wood indexing, Prunus serrulata cv. Kwanzan plants were graft-inoculated with chip buds from the CNRMV-positive sweet cherry trees. At 3 to 4 weeks post-inoculation, the Kwanzan plants showed quick decline with leaves wilting and dying; CNRMV infection of the indicators was confirmed by RT-PCR. To our knowledge, this is the first report of CNRMV infection of sweet cherry trees in Korea. Screening for CNRMV in propagation nurseries should minimize spread of this virus within Korea. References: (1) R. Li and R. Mock. Arch. Virol. 153:973, 2008. (2) R. Li and R. Mock. J. Virol. Methods 129:162, 2005.

10.
Eye (Lond) ; 27(12): 1339-46, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24202051

ABSTRACT

PURPOSE: To review and evaluate the effects of intravitreal bevacizumab injection (IVB) in centralserous chorioretinopathy (CSC) by meta-analysis. PATIENTS AND METHODS: Clinical controlled studies that evaluated the effect of IVB in CSC were identified through systematic searches of Embase, PubMed, and the Cochrane Central Register of Controlled Trials. Data on the best-corrected visual acuity (BCVA) in logMAR and central macular thickness (CMT) in µm at baseline and 6 months after IVB were extracted and compared with those treated by simple observation. RESULTS: Four clinical controlled studies were included in the meta-analysis. The IVB injection group achieved better BCVA at a follow-up of 6 months. However, the analysis showed that there were no significant differences of BCVA at 6 months after injection between IVB group and the observation group (-0.02 logMAR, 95% CI -0.14 to 0.11, P=0.80). The analysis of the reduction in CMT revealed that the difference between groups was not statistically significant (-8.37 µm, 95% CI -97.26 to 80.52, P=0.85). No report assessed severe complications or side effects of IVB in patients with CSC. CONCLUSIONS: Meta-analysis failed to verify the positive effect of IVB in CSC based on the epidemiological literature published to date.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Central Serous Chorioretinopathy/drug therapy , Bevacizumab , Central Serous Chorioretinopathy/physiopathology , Humans , Intravitreal Injections , Treatment Outcome , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Visual Acuity/physiology
11.
Neuroscience ; 246: 271-80, 2013 Aug 29.
Article in English | MEDLINE | ID: mdl-23673275

ABSTRACT

The executive clock drawing task (CLOX) is one of the widely used clock drawing tests (CDTs) and is composed of CLOX1, an unprompted CDT, and CLOX2, a simple copying CDT. Although it is conceptually believed that CLOX1 is sensitive to both executive function and constructional ability while CLOX2 reflects only constructional ability, there are still lack of studies on the functional neuroanatomical substrates of CLOX1 and 2 performances. This study aimed to identify the functional brain correlates of CLOX1 and 2 performances in patients with Alzheimer's disease (AD). CLOX was administered to 139 AD patients and 50 normal controls, and regional cerebral glucose metabolism (rCMglc) was measured by (18)F-fluoro-2-deoxy-glucose positron emission tomography. Correlations between CLOX scores and rCMglc were examined on a voxel-by-voxel basis in AD patients. For the overall AD group, significant positive correlations between CLOX1 and rCMglc were found in the bilateral temporo-parietal and left middle frontal regions, while CLOX2 was correlated with rCMglc of the bilateral temporo-parietal regions. Additional subgroup analysis showed that CLOX1 was associated with the left temporal metabolism in less severe AD, and with the right temporo-parietal metabolism in more severe AD. In contrast, CLOX2 was correlated with rCMglc of the diffuse right fronto-temporo-parietal regions in more severe AD, but not with any rCMglc in less severe AD. This is the first neuroimaging study on the functional neuroanatomical correlates of CLOX performances in AD. Given the relationships between specific cognitive performances and regional brain functions, the findings probably support the notion that CLOX1 demands not merely visuospatial functions but also executive control, while CLOX2 depends mainly on visuospatial ability. Our results also indicate that each CLOX performance depends on very different functional brain regions according to AD clinical stages.


Subject(s)
Alzheimer Disease/diagnostic imaging , Brain/diagnostic imaging , Executive Function/physiology , Neuropsychological Tests , Positron-Emission Tomography/methods , Psychomotor Performance/physiology , Aged , Aged, 80 and over , Alzheimer Disease/psychology , Female , Fluorodeoxyglucose F18 , Humans , Male , Middle Aged
12.
Int J Lab Hematol ; 35(6): 629-36, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23693053

ABSTRACT

INTRODUCTION: The aim of this study was to characterize clinicopathological features of acute panmyelosis with myelofibrosis (APMF), acute megakaryoblastic leukemia with myelofibrosis (AMKL-MF), primary myelofibrosis (PMF) and myelodysplastic syndrome with myelofibrosis (MDS-MF) in order to provide the keys to the differential diagnosis of bone marrow (BM) fibrosis. METHODS: We compared age, gender, splenomegaly, serum lactate dehydrogenase level, blood cell counts, blast counts in peripheral blood (PB) and BM, megakaryocyte counts, BM cellularity, dysplasia, and the karyotypes of patients with APMF (n = 6), AMKL-MF (n = 7), PMF (n = 44), and MDS-MF (n = 44). RESULTS: APMF showed hyperplasia of all three lineages, increase in megakaryocyte count with dysplasia and frequent abnormal karyotypes. AMKL-MF was associated with elevated BM blast counts, decreased BM megakaryocyte count with rare megakaryocytic dysplasia and chromosome 21 abnormality. PMF patients displayed splenomegaly, rare blasts in PB/BM, and JAK2 V617F mutation. MDS-MF patients showed pancytopenia, dysplasia in all three lineages and recurrent chromosomal abnormalities involving chromosome 5,7,12, and 17. CONCLUSIONS: Although differential diagnosis among APMF, AMKL-MF, PMF, and MDS-MF is very challenging due to the overlapping clinical and morphological features, meticulous investigation of the patient with respect to splenomegaly, blood cell count, PB and BM findings, and karyotype will serve as a guide to correct diagnosis.


Subject(s)
Leukemia, Megakaryoblastic, Acute/diagnosis , Myelodysplastic Syndromes/diagnosis , Primary Myelofibrosis/diagnosis , Adult , Aged , Aged, 80 and over , Bone Marrow/pathology , Child , Child, Preschool , Diagnosis, Differential , Female , Humans , Infant , Karyotyping , Leukemia, Megakaryoblastic, Acute/blood , Leukemia, Megakaryoblastic, Acute/genetics , Leukemia, Megakaryoblastic, Acute/pathology , Male , Middle Aged , Myelodysplastic Syndromes/blood , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/pathology , Primary Myelofibrosis/blood , Primary Myelofibrosis/genetics , Primary Myelofibrosis/pathology , Young Adult
13.
Int J Lab Hematol ; 35(6): 589-600, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23575252

ABSTRACT

INTRODUCTION: ABL1 kinase mutations represent a major mechanism of imatinib resistance in Philadelphia-positive (Ph+) patients. There is a paucity of data on ABL1 kinase mutations in Ph+ patients in Korea. METHODS: We used restriction fragment mass polymorphism (RFMP) analysis to detect ABL1 kinase mutations in blood or bone marrow specimens from 80 Ph+ patients. RESULTS: Fifty-seven patients met the criteria for inadequate molecular response (IMR). ABL1 kinase mutations were found in 2.6% of patients with chronic-phase chronic myelogenous leukemia (CML), 25.0% of accelerated-phase CML, 66.7% of blast-phase CML, and in 58.3% with Ph+ acute lymphoblastic leukemia. Twelve mutations were identified: 7 T315I, 2 E255V, 1 E255K, 1 F359V, and 1 Y253H. The majority of mutation-positive patients showed an unfavorable clinical course and often had an extra Ph or additional chromosomal abnormalities. Mutations were detected in two patients who had very low or absent BCR-ABL1 normalized ratios. CONCLUSION: Mutation analysis should be performed in Ph+ patients exhibiting an IMR to imatinib. RFMP analysis is helpful for revising therapeutic strategies because it can sensitively detect clinically relevant ABL1 kinase mutations with high frequencies.


Subject(s)
Fusion Proteins, bcr-abl/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Mutation , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Protein Interaction Domains and Motifs/genetics , Adolescent , Adult , Aged , Child , Chromosome Aberrations , Codon , DNA Mutational Analysis , Drug Resistance, Neoplasm/genetics , Female , Fusion Proteins, bcr-abl/chemistry , Humans , Karyotype , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Male , Middle Aged , Polymorphism, Restriction Fragment Length , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/therapeutic use , Treatment Outcome , Young Adult
14.
Int J Lab Hematol ; 34(5): 541-6, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22672327

ABSTRACT

INTRODUCTION: Interphase fluorescence in situ hybridization (FISH) analysis of multiple myeloma (MM) may indiscriminately count signals of nonplasma cells, thus decreasing specificity and sensitivity. We aimed to evaluate the usefulness of an immune-magnetic sorting method for plasma cells in FISH analysis of MM and define optimal sample preparation conditions. METHODS: Plasma cells were purified using EasySep(®) CD138 Positive Selection Cocktail and Magnetic Nanoparticles (Invitrogen). We compared FISH results with and without plasma cell purification for three sample preparation methods: direct harvest, 24-h culture, and 96-h culture with interleukin-4 in five newly diagnosed MM patients. Archived fixed bone marrow cells of 17 MM patients were also studied. RESULTS: The percentage of abnormal cells identified was significantly higher with plasma cell purification than without purification (median, 88.0%; range, 84.0-100.0%vs. 15.0%, 12.5-29.5%, respectively). The three sample preparation methods showed comparable results. Immune-magnetic sorting also significantly increased the percentage of abnormal cells identified in FISH analysis of archived fixed bone marrow cells (P < 0.001). CONCLUSIONS: Immune-magnetic CD138-positive cell sorting significantly increased the percentage of abnormal cells identified in FISH analysis of MM samples for all sample preparation methods. This method could also be applied for retrospective FISH analysis of archived fixed bone marrow cells.


Subject(s)
Immunomagnetic Separation/methods , In Situ Hybridization, Fluorescence/methods , Multiple Myeloma/metabolism , Plasma Cells/metabolism , Syndecan-1/analysis , Cell Count , Cell Culture Techniques , Cells, Cultured , Flow Cytometry , Humans , Immunophenotyping , Multiple Myeloma/genetics , Multiple Myeloma/pathology , Reproducibility of Results
15.
Phys Rev Lett ; 108(13): 131301, 2012 Mar 30.
Article in English | MEDLINE | ID: mdl-22540691

ABSTRACT

In two long-duration balloon flights over Antarctica, the Balloon-borne Experiment with a Superconducting Spectrometer (BESS) collaboration has searched for antihelium in the cosmic radiation with the highest sensitivity reported. BESS-Polar I flew in 2004, observing for 8.5 days. BESS-Polar II flew in 2007-2008, observing for 24.5 days. No antihelium candidate was found in BESS-Polar I data among 8.4×10(6) |Z|=2 nuclei from 1.0 to 20 GV or in BESS-Polar II data among 4.0×10(7) |Z|=2 nuclei from 1.0 to 14 GV. Assuming antihelium to have the same spectral shape as helium, a 95% confidence upper limit to the possible abundance of antihelium relative to helium of 6.9×10(-8)} was determined combining all BESS data, including the two BESS-Polar flights. With no assumed antihelium spectrum and a weighted average of the lowest antihelium efficiencies for each flight, an upper limit of 1.0×10(-7) from 1.6 to 14 GV was determined for the combined BESS-Polar data. Under both antihelium spectral assumptions, these are the lowest limits obtained to date.

16.
Phys Rev Lett ; 108(5): 051102, 2012 Feb 03.
Article in English | MEDLINE | ID: mdl-22400920

ABSTRACT

The energy spectrum of cosmic-ray antiprotons (p's) from 0.17 to 3.5 GeV has been measured using 7886 p's detected by BESS-Polar II during a long-duration flight over Antarctica near solar minimum in December 2007 and January 2008. This shows good consistency with secondary p calculations. Cosmologically primary p's have been investigated by comparing measured and calculated p spectra. BESS-Polar II data show no evidence of primary p's from the evaporation of primordial black holes.

17.
Br J Dermatol ; 166(2): 337-42, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21967648

ABSTRACT

BACKGROUND: Seborrhoeic keratoses (SKs) are very common benign epidermal lesions without malignant potential. Ultraviolet radiation, old age and viruses are well-known risk factors for disease development. However, the pathomechanisms of SK are not fully understood. OBJECTIVES: To detect and characterize the genes that are involved in the pathogenesis of SK. METHODS: We performed a gene expression study using paired lesional and nonlesional skin samples from patients with SK. RESULTS: We identified and validated 19 differentially expressed genes in SK. Of these 19 genes, we focused on p63 transcription factor, which plays a pivotal role in epidermal development by regulating its transcriptional programme. We found by immunofluorescence that the expression of ΔNp63α, the most abundantly expressed p63 isoform, was significantly increased in SK as compared with normal skin. Moreover, siRNA-mediated knockdown of ΔNp63 led to the downregulation of 11 genes, including a member of the tensin family TNS4. Chromatin immunoprecipitation assay revealed that TNS4 was a target gene of p63. CONCLUSIONS: We identified upregulated genes in SK using genome-wide cDNA microarray and elucidated the functional contribution of p63 to the disease transcriptome by gene-silencing assay. Taken together, these data may provide a novel insight into the molecular basis of these benign skin lesions.


Subject(s)
Keratosis, Seborrheic/genetics , Transcription Factors/genetics , Tumor Suppressor Proteins/genetics , Aged , Aged, 80 and over , Female , Gene Expression , Gene Knockdown Techniques , Gene Silencing/physiology , Humans , Keratosis, Seborrheic/metabolism , Male , Microarray Analysis/methods , Microfilament Proteins/genetics , Middle Aged , Real-Time Polymerase Chain Reaction , Tensins , Transcription Factors/metabolism , Transcription Factors/physiology , Tumor Suppressor Proteins/metabolism , Tumor Suppressor Proteins/physiology , Up-Regulation
18.
Oncogene ; 31(18): 2270-82, 2012 May 03.
Article in English | MEDLINE | ID: mdl-21927024

ABSTRACT

Tumors are thought to be sustained by a reservoir of self-renewing cells, termed tumor-initiating cells or cancer stem cells. Osteosarcomas are high-grade sarcomas derived from osteoblast progenitor cells and are the most common pediatric bone malignancy. In this report we show that the stem cell transcription factor Sox2 is highly expressed in human and murine osteosarcoma (mOS) cell lines as well as in the tumor samples. Osteosarcoma cells have increased ability to grow in suspension as osteospheres, that are greatly enriched in expression of Sox2 and the stem cell marker, Sca-1. Depletion of Sox2 by short-hairpin RNAs in independent mOS-derived cells drastically reduces their transformed properties in vitro and their ability to form tumors. Sox2-depleted osteosarcoma cells can no longer form osteospheres and differentiate into mature osteoblasts. Concomitantly, they exhibit decreased Sca-1 expression and upregulation of the Wnt signaling pathway. Thus, despite other mutations, these cells maintain a requirement for Sox2 for tumorigenicity. Our data indicate that Sox2 is required for osteosarcoma cell self renewal, and that Sox2 antagonizes the pro-differentiation Wnt pathway that can in turn reduce Sox2 expression. These studies define Sox2 as a survival factor and a novel biomarker of self renewal in osteosarcomas, and support a tumor suppressive role for the Wnt pathway in tumors of mesenchymal origin. Our findings could provide the basis for novel therapeutic strategies based on inhibiting Sox2 or enhancing Wnt signaling for the treatment of osteosarcomas.


Subject(s)
Bone Neoplasms/genetics , Cell Proliferation , Neoplastic Stem Cells , Osteosarcoma/genetics , SOXB1 Transcription Factors/genetics , Animals , Antigens, Ly/genetics , Antigens, Ly/metabolism , Antigens, Surface/genetics , Antigens, Surface/metabolism , Bone Neoplasms/pathology , Cell Differentiation/genetics , Cell Line, Tumor , Cell Transformation, Neoplastic/genetics , Humans , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Osteosarcoma/pathology , Signal Transduction , Wnt Signaling Pathway
19.
Int J Lab Hematol ; 34(3): 328-32, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22122800

ABSTRACT

Although most patients with peripheral T-cell lymphoma (PTCL) show clonal rearrangement of T-cell receptor genes, few PTCLs show recurrent chromosomal abnormalities. We describe here a rare chromosomal rearrangement, t(14;19)(q11.2;q13.3), in a Lennert's lymphoma, a variant of PTCL, not otherwise specified. Sequential fluorescence in situ hybridization assays showed that the breakpoint in 19q13.3 was located distal to the BCL3 and PVRL2 genes, both of which may be candidate proto-oncogenes. These findings suggest that another gene is involved in the pathogenic characteristics observed in this patient with Lennert's lymphoma.


Subject(s)
Chromosome Aberrations , Chromosomes, Human, Pair 14 , Chromosomes, Human, Pair 19 , Lymphoma, T-Cell, Peripheral/genetics , Female , Humans , In Situ Hybridization, Fluorescence , Lymphoma, T-Cell, Peripheral/pathology , Middle Aged
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