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1.
Phys Rev Lett ; 130(5): 051801, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800472

RESUMO

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νßß) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>2.3×10^{26} yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

2.
Neuropathol Appl Neurobiol ; 46(2): 111-124, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31179566

RESUMO

AIMS: Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown. METHODS: We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases. RESULTS: Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%). CONCLUSIONS: The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/imunologia , Linhagem da Célula/imunologia , Germinoma/diagnóstico , Germinoma/imunologia , Neoplasias Encefálicas/metabolismo , Perfilação da Expressão Gênica , Germinoma/metabolismo , Humanos , Prognóstico , Transcriptoma , Microambiente Tumoral/imunologia
4.
Rev Sci Instrum ; 87(11): 11D424, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910550

RESUMO

In the divertor simulation experiments in the GAMMA 10/PDX tandem mirror, pressure of the neutral gas was investigated by using a fast ionization gauge. The gauge was absolutely calibrated for hydrogen gas by using a capacitance manometer. Change of the gauge sensitivity due to the magnetic field of GAMMA 10/PDX was also evaluated. The typical gas pressure measured in detached plasma experiments was 0.1-10 Pa. The degree of plasma detachment determined from the reduction of heat flux was enhanced as the gas pressure increases. Rapid increase of the gas pressure under the plasma flow was also observed.

5.
Neuropathol Appl Neurobiol ; 42(3): 279-90, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26111727

RESUMO

AIMS: Primary central nervous system lymphoma (PCNSL) manifest aggressive clinical behaviour and have poor prognosis. Although constitutive activation of the nuclear factor-κB (NF-κB) pathway has been documented, knowledge about the genetic alterations leading to the impairment of the NF-κB pathway in PCNSLs is still limited. This study was aimed to unravel the underlying genetic profiles of PCNSL. METHODS: We conducted the systematic sequencing of 21 genes relevant to the NF-κB signalling network for 71 PCNSLs as well as the pyrosequencing of CD79B and MYD88 mutation hotspots in a further 35 PCNSLs and 46 glioblastomas (GBMs) for validation. RESULTS: The results showed that 68 out of 71 PCNSLs had mutations in the NF-κB gene network, most commonly affecting CD79B (83%), MYD88 (76%), TBL1XR1 (23%), PRDM1 (20%) and CREBBP1 (20%). These mutations, particularly CD79B and MYD88, frequently coincided within each tumour in various combinations, simultaneously affecting diverse pathways within the network. No GBMs had hotspot mutation of CD79B Y196 and MYD88 L265. CONCLUSIONS: The prevalence of CD79B and MYD88 mutations in PCNSLs was considerably higher than reported in systemic diffuse large B-cell lymphomas. This observation could reflect the paucity of antigen stimuli from the immune system in the central nervous system (CNS) and the necessity to substitute them by the constitutive activation of CD79B and MYD88 that would initiate the signalling cascades. These hotspot mutations may serve as a genetic hallmark for PCNSL serving as a genetic marker for diagnose and potential targets for molecular therapy.


Assuntos
Antígenos CD79/genética , Neoplasias do Sistema Nervoso Central/genética , Linfoma Difuso de Grandes Células B/genética , Fator 88 de Diferenciação Mieloide/genética , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase
6.
Phys Rev Lett ; 113(12): 121301, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25279618

RESUMO

Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4) kg-1 keVee-1 day-1 in the detector.

7.
Clin Exp Dermatol ; 39(8): 911-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25283968

RESUMO

Skin perfusion pressure (SPP) is the perfusion pressure at the skin level, and it can serve as an index of peripheral circulation in the skin and subcutaneous tissue. We report a 78-year-old man with critical limb ischaemia who, despite having undergone several catheter interventions, still had severe ulcers with exposed bone on his right foot. We performed transmetatarsal amputation. The tissue around the surgical site became necrotic several days later, and did not respond to conservative therapy. Therefore, we opted for maggot debridement therapy (MDT), given that maggots favour necrotic tissue. After the therapy, SPP around the ulcer increased from 12 to 54 mmHg on the dorsal aspect, and from 17 to 44 mmHg on the plantar aspect. Wound healing was successfully activated by MDT, leading to complete healing within 2.5 months after MDT. We believe that MDT probably contributed to increase the blood supply to the ischaemic wound.


Assuntos
Desbridamento/métodos , Isquemia/terapia , Pele/irrigação sanguínea , Cicatrização , Ferimentos e Lesões/terapia , Idoso , Amputação Cirúrgica , Animais , Dípteros , Humanos , Larva , Perna (Membro)/irrigação sanguínea , Masculino , Necrose/terapia , Resultado do Tratamento
8.
J Laryngol Otol ; 128(10): 935-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25120243

RESUMO

BACKGROUND: Revision laryngeal framework surgery is usually performed for medialisation laryngoplasty failure, rather than for failure after arytenoid adduction. We describe a new method for revision arytenoid adduction surgery, performed by directly pulling the lateral cricoarytenoid muscle ('lateral cricoarytenoid muscle pull surgery'). METHODS: We describe a case of revision laryngeal framework surgery, present a literature review and describe the advantages of lateral cricoarytenoid muscle pull surgery over the original method of arytenoid adduction using a posterior approach. RESULTS: Medialisation laryngoplasty combined with arytenoid adduction was performed following unilateral vocal fold paralysis from mediastinal surgery, resulting in severe glottic insufficiency. The patient's voice improved after the initial surgery, but had deteriorated 18 months later. Revision surgery was performed using lateral cricoarytenoid muscle pull surgery, and her voice recovered normally in terms of perceptual impression. The post-operative course was uneventful for 10 months following revision surgery. CONCLUSION: To our knowledge, this is the first case of revision arytenoid adduction performed using a lateral cricoarytenoid muscle pull approach. Lateral cricoarytenoid muscle pull surgery should therefore be considered as a new fenestration approach for arytenoid adduction.


Assuntos
Músculos Laríngeos/cirurgia , Reoperação/métodos , Paralisia das Pregas Vocais/cirurgia , Idoso , Transtornos da Articulação/cirurgia , Feminino , Humanos , Literatura de Revisão como Assunto , Resultado do Tratamento
9.
J Laryngol Otol ; 126(11): 1114-20, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22989870

RESUMO

OBJECTIVE: This study aimed to investigate the function of tissue plasminogen activator in the olfactory epithelium of mice following neural injury. METHOD: Transmission electron microscopy was used to study the changes in the morphology of the olfactory epithelium 1-7 days after surgical ablation of the olfactory bulb (bulbectomy). RESULTS: Prior to bulbectomy, a uniformly fine material was observed within some regions of the olfactory epithelium of mice deficient in tissue plasminogen activator. At 2-3 days after bulbectomy, there were degenerative changes in the olfactory epithelium. At 5-7 days after bulbectomy, we noted drastic differences in olfactory epithelium morphology between mice deficient in tissue plasminogen activator and wild-type mice (comparisons were made using findings from a previous study). The microvilli seemed to be normal and olfactory vesicles and receptor neuron dendrites were largely intact in the olfactory epithelium of mice deficient in tissue plasminogen activator. CONCLUSION: The tissue plasminogen activator plasmin system may inhibit the regeneration of the olfactory epithelium in the early stages following neural injury.


Assuntos
Bulbo Olfatório/fisiologia , Bulbo Olfatório/cirurgia , Mucosa Olfatória/fisiologia , Regeneração/fisiologia , Ativador de Plasminogênio Tecidual/deficiência , Animais , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mucosa Olfatória/citologia , Ativador de Plasminogênio Tecidual/fisiologia
10.
Mol Plant Microbe Interact ; 25(11): 1419-29, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22835272

RESUMO

The rough lemon pathotype of Alternaria alternata produces host-selective ACR-toxin and causes Alternaria leaf spot disease of rough lemon (Citrus jambhiri). The structure of ACR-toxin I (MW = 496) consists of a polyketide with an α-dihydropyrone ring in a 19-carbon polyalcohol. Genes responsible for toxin production were localized to a 1.5-Mb chromosome in the genome of the rough lemon pathotype. Sequence analysis of this chromosome revealed an 8,338-bp open reading frame, ACRTS2, that was present only in the genomes of ACR-toxin-producing isolates. ACRTS2 is predicted to encode a putative polyketide synthase of 2,513 amino acids and belongs to the fungal reducing type I polyketide synthases. Typical polyketide functional domains were identified in the predicted amino acid sequence, including ß-ketoacyl synthase, acyl transferase, methyl transferase, dehydratase, ß-ketoreductase, and phosphopantetheine attachment site domains. Combined use of homologous recombination-mediated gene disruption and RNA silencing allowed examination of the functional role of multiple paralogs in ACR-toxin production. ACRTS2 was found to be essential for ACR-toxin production and pathogenicity of the rough lemon pathotype of A. alternata.


Assuntos
Alternaria/enzimologia , Alternaria/metabolismo , Citrus/microbiologia , Proteínas Fúngicas/metabolismo , Policetídeo Sintases/metabolismo , Alternaria/genética , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Policetídeo Sintases/genética
11.
Neuropathol Appl Neurobiol ; 36(6): 505-14, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20831745

RESUMO

AIMS: Loss of both wild-type copies of the neurofibromatosis type 2 (NF2) gene is found in both sporadic and neurofibromatosis type 2-associated vestibular schwannomas (VS). Previous studies have identified a subset of VS with no loss or mutation of NF2. We hypothesized that methylation of NF2 resulting in gene silencing may play a role in such tumours. METHODS: Forty sporadic VS were analysed by array comparative genomic hybridization using 1 Mb whole genome and chromosome 22 tile path arrays. The NF2 genes were sequenced and methylation of NF2 examined by pyrosequencing. RESULTS: Monosomy 22 was the only recurrent change found. Twelve tumours had NF2 mutations. Eight tumours had complete loss of wild-type NF2, four had one mutated and one wild-type allele, 11 had only one wild-type allele and 17 showed no abnormalities. Methylation analysis showed low-level methylation in four tumours at a limited number of CpGs. No high-level methylation was found. CONCLUSIONS: This study shows that a significant proportion of sporadic VS (>40%) have unmethylated wild-type NF2 genes. This indicates that other mechanisms, yet to be identified, are operative in the oncogenesis of these VSs.


Assuntos
Ilhas de CpG/genética , Metilação de DNA/genética , Genes da Neurofibromatose 2 , Neuroma Acústico/genética , Adulto , Idoso , Hibridização Genômica Comparativa , Análise Mutacional de DNA , Feminino , Dosagem de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Mutação
12.
Mol Plant Microbe Interact ; 23(4): 406-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20192828

RESUMO

The tangerine pathotype of Alternaria alternata produces host-selective ACT-toxin and causes Alternaria brown spot disease of tangerine and tangerine hybrids. Sequence analysis of a genomic BAC clone identified part of the ACT-toxin TOX (ACTT) gene cluster, and knockout experiments have implicated several open reading frames (ORF) contained within the cluster in the biosynthesis of ACT-toxin. One of the ORF, designated ACTTS3, encoding a putative polyketide synthase, was isolated by rapid amplification of cDNA ends and genomic/reverse transcription-polymerase chain reactions using the specific primers designed from the BAC sequences. The 7,374-bp ORF encodes a polyketide synthase with putative beta-ketoacyl synthase, acyltransferase, methyltransferase, beta-ketoacyl reductase, and phosphopantetheine attachment site domains. Genomic Southern blots demonstrated that ACTTS3 is present on the smallest chromosome in the tangerine pathotype of A. alternata, and the presence of ACTTS3 is highly correlated with ACT-toxin production and pathogenicity. Targeted gene disruption of two copies of ACTTS3 led to a complete loss of ACT-toxin production and pathogenicity. These results indicate that ACTTS3 is an essential gene for ACT-toxin biosynthesis in the tangerine pathotype of A. alternata and is required for pathogenicity of this fungus.


Assuntos
Alternaria/genética , Alternaria/metabolismo , Citrus/microbiologia , Micotoxinas/metabolismo , Policetídeo Sintases/metabolismo , Alternaria/classificação , Alternaria/patogenicidade , Regulação Fúngica da Expressão Gênica/fisiologia , Dados de Sequência Molecular , Estrutura Molecular , Micotoxinas/química , Micotoxinas/genética , Doenças das Plantas/microbiologia , Policetídeo Sintases/genética
14.
Phys Rev Lett ; 105(17): 176401, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21231061

RESUMO

We discovered the chirality of charge-density waves (CDW) in 1T-TiSe2 by using STM and time-domain optical polarimetry. We found that the CDW intensity becomes Ia1∶Ia2∶Ia3 = 1∶0.7 ± 0.1∶0.5 ± 0.1, where Ia(i) (i=1,2,3) is the amplitude of the tunneling current contributed by the CDWs. There were two states, in which the three intensity peaks of the CDW decrease clockwise and anticlockwise. The chirality in CDW results in the threefold symmetry breaking. Macroscopically, twofold symmetry was indeed observed in optical measurement. We propose the new generalized CDW chirality H(CDW) ≡ q1·(q2×q3), where q(i) are the CDW q vectors, which is independent of the symmetry of components. The nonzero H(CDW)-the triple-q vectors do not exist in an identical plane in the reciprocal space-should induce a real-space chirality in CDW system.

16.
Oncogene ; 28(20): 2119-23, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19363522

RESUMO

Pilocytic astrocytomas (PAs), WHO malignancy grade I, are the most frequently occurring central nervous system tumour in 5- to 19-year-olds. Recent reports have highlighted the importance of MAPK pathway activation in PAs, particularly through a tandem duplication leading to an oncogenic BRAF fusion gene. Here, we report two alternative mechanisms resulting in MAPK activation in PAs. Firstly, in striking similarity to the common BRAF fusion, tandem duplication at 3p25 was observed, which produces an in-frame oncogenic fusion between SRGAP3 and RAF1. This fusion includes the Raf1 kinase domain, and shows elevated kinase activity when compared with wild-type Raf1. Secondly, a novel 3 bp insertion at codon 598 in BRAF mimics the hotspot V600E mutation to produce a transforming, constitutively active BRaf kinase. Although these two alterations are not common, they bring the number of cases with an identified 'hit' on the Ras/Raf-signalling pathway to 36 from our series of 44 (82%), confirming its central importance to the development of pilocytic astrocytomas.


Assuntos
Astrocitoma/genética , Rearranjo Gênico , Sistema de Sinalização das MAP Quinases/fisiologia , Mutação/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-raf/genética , Animais , Astrocitoma/metabolismo , Astrocitoma/patologia , Hibridização Genômica Comparativa , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Camundongos , Células NIH 3T3 , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-raf/metabolismo
17.
J Pathol ; 217(3): 420-30, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19006194

RESUMO

The genetic basis of MALT lymphoma is largely unknown. Characteristic chromosomal translocations are frequently associated with gastric and pulmonary cases, but are rare at other sites. We compared the genetic profiles of 33 ocular adnexal and 25 pulmonary MALT lymphomas by 1 Mb array-comparative genomic hybridization (CGH) and revealed recurrent 6q23 losses and 6p21.2-6p22.1 gains exclusive to ocular cases. High-resolution chromosome 6 tile-path array-CGH identified NF-kappaB inhibitor A20 as the target of 6q23.3 deletion and TNFA/B/C locus as a putative target of 6p21.2-22.1 gain. Interphase fluorescence in situ hybridization showed that A20 deletion occurred in MALT lymphoma of the ocular adnexa (8/42=19%), salivary gland (2/24=8%), thyroid (1/9=11%) and liver (1/2), but not in the lung (26), stomach (45) and skin (13). Homozygous deletion was observed in three cases. A20 deletion and TNFA/B/C gain were significantly associated (p<0.001) and exclusively found in cases without characteristic translocation. In ocular cases, A20 deletion was associated with concurrent involvement of different adnexal tissues or extraocular sites at diagnosis (p=0.007), a higher proportion of relapse (67% versus 37%) and a shorter relapse-free survival (p=0.033). A20 deletion and gain at TNFA/B/C locus may thus play an important role in the development of translocation-negative MALT lymphoma.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Linfoma de Zona Marginal Tipo Células B/genética , Proteínas Nucleares/genética , Neoplasias Orbitárias/genética , Neoplasias das Glândulas Salivares/genética , Fator de Necrose Tumoral alfa/genética , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Cromossomos Humanos Par 6 , Hibridização Genômica Comparativa/métodos , Proteínas de Ligação a DNA , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Hibridização in Situ Fluorescente , Interfase , Neoplasias Hepáticas/genética , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Deleção de Sequência , Neoplasias Cutâneas/genética , Neoplasias Gástricas/genética , Neoplasias da Glândula Tireoide/genética , Translocação Genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa
18.
Neuropathol Appl Neurobiol ; 35(4): 353-366, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19017278

RESUMO

AIMS: We report a comparative study on the mRNA expression of ErbB receptor tyrosine kinases, and in particular ERBB4 transcript variants, in two common paediatric brain tumours: medulloblastoma (MB) and pilocytic astrocytoma (PA). METHODS: While the conventional real-time quantitative polymerase chain reaction was used to measure the expression of ERRBs and ErbB4-processing protease genes, the LightCycler fluorescence resonance energy transfer probes were specifically designed to investigate all of the known ERBB4 juxtamembrane (JM) and cytoplasmic transcript variants. RESULTS: The overall expression of ERBBs suggests that ErbB2/ErbB4 heterodimers and ErbB4 homodimers may be major functional units of the ErbBs in MB, while ErbB2/ErbB3 heterodimers may play a more prominent role in addition to ErbB4-containing dimers in PA. Different expression patterns of ERBB4 JM transcripts in MB, PA and normal brain were observed. The JM-d variant was only detected in MBs, while JM-c was present in MB and PA but was not identified in normal brain. The expression of cleavable ERBB4 transcript variants was elevated in PAs and MBs compared with normal brain, while mRNA levels of ErbB4-processing proteases were similar in both tumour types and normal brain. This suggests that proteolytic cleavage of ErbB4 may be more common in MB and PA, which leads to signalling events divergent from those in normal brain. CONCLUSION: Taken together, these results suggest that ErbB4 processing and function may be altered in brain tumours, such as MB and PA, via differential expression of JM transcript variants.


Assuntos
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Receptores ErbB/metabolismo , Meduloblastoma/metabolismo , Astrocitoma/genética , Neoplasias Encefálicas/genética , Cerebelo/metabolismo , Receptores ErbB/genética , Transferência Ressonante de Energia de Fluorescência , Expressão Gênica , Variação Genética , Humanos , Meduloblastoma/genética , Peptídeo Hidrolases/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Receptor ErbB-4
19.
Br J Cancer ; 99(7): 1144-52, 2008 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-18781178

RESUMO

The MDM2 gene is amplified and/or overexpressed in about 10% of glioblastomas and constitutes one of a number of ways the p53 pathway is disrupted in these tumours. MDM2 encodes a nuclear phosphoprotein that regulates several cell proteins by binding and/or ubiquitinating them, with p53 being a well-established partner. MDM2 has two promoters, P1 and P2 that give rise to transcripts with distinct 5' untranslated regions. Transcription from P2 is believed to be controlled by p53 and a single-nucleotide polymorphism (SNP309, T>G) in P2 is reported to be associated with increased risk for, and early development of, malignancies. The use of P1 and P2 has not been investigated in gliomas. We used RT-PCR to study P1- and P2-MDM2 transcript expression in astrocytic tumours, xenografts and cell lines with known MDM2, TP53 and p14(ARF) gene status. Both promoters were used in all genetic backgrounds including the use of the P2 promoter in TP53 null cells, indicating a p53-independent induction of transcription. Transcripts from the P1 promoter formed a greater proportion of the total MDM2 transcripts in tumours with MDM2 amplification, despite these tumours having two wild-type TP53 alleles. Examination of SNP309 in glioblastoma patients showed a borderline association with survival but no apparent correlation with age at diagnosis nor with TP53 and p14(ARF) status of their tumours. Our findings also indicate that elevated MDM2 mRNA levels in tumours with MDM2 amplification are preferentially driven by the P1 promoter and that the P2 promoter is not only regulated by p53 but also by other transcription factor(s).


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/fisiologia , Adulto , Genótipo , Humanos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Phys Rev Lett ; 100(22): 221803, 2008 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-18643415

RESUMO

The KamLAND experiment has determined a precise value for the neutrino oscillation parameter Deltam21(2) and stringent constraints on theta12. The exposure to nuclear reactor antineutrinos is increased almost fourfold over previous results to 2.44 x 10(32) proton yr due to longer livetime and an enlarged fiducial volume. An undistorted reactor nu[over]e energy spectrum is now rejected at >5sigma. Analysis of the reactor spectrum above the inverse beta decay energy threshold, and including geoneutrinos, gives a best fit at Deltam21(2)=7.58(-0.13)(+0.14)(stat) -0.15+0.15(syst) x 10(-5) eV2 and tan2theta12=0.56(-0.07)+0.10(stat) -0.06+0.10(syst). Local Deltachi2 minima at higher and lower Deltam21(2) are disfavored at >4sigma. Combining with solar neutrino data, we obtain Deltam21(2)=7.59(-0.21)+0.21 x 10(-5) eV2 and tan2theta12=0.47(-0.05)+0.06.

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