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1.
Rep Prog Phys ; 80(4): 046201, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28000608

RESUMO

The phenomenon of CP violation is crucial to understand the asymmetry between matter and antimatter that exists in the Universe. Dramatic experimental progress has been made, in particular in measurements of the behaviour of particles containing the b quark, where CP violation effects are predicted by the Kobayashi-Maskawa mechanism that is embedded in the standard model. The status of these measurements and future prospects for an understanding of CP violation beyond the standard model are reviewed.

2.
Childs Nerv Syst ; 32(8): 1359-62, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27312077

RESUMO

BACKGROUND: Central nervous system (CNS) germ cell tumors account for 3 % of all pediatric brain tumors in the USA. Presenting symptoms are typically location based with pineal tumors presenting with obstructive hydrocephalus and suprasellar tumors with hypothalamic/pituitary dysfunction and ophthalmologic abnormalities. Psychiatric manifestations such as psychosis and behavioral changes are atypical presentations of CNS germ cell tumors, with only 11 previously reported cases. METHODS: This is a retrospective case series describing patients with CNS germ cell tumors with an atypical presentation including psychiatric manifestations. Information regarding clinical presentation, treatment course, and outcome were obtained. RESULTS: We report seven patients who presented with psychiatric symptoms consisting of psychomotor delay as well as behavioral and mood changes. Six of the seven patients were diagnosed ≥6 months after onset of psychiatric symptoms. All of the seven are alive but five continue to have neurologic and psychiatric issues post treatment. CONCLUSIONS: Atypical presentations of CNS germ cell tumors can delay diagnosis and treatment and may be secondary to atypical locations as well as endocrine dysfunction manifesting as psychiatric symptoms. Delayed diagnosis did not appear to affect survival but earlier diagnosis may potentially be associated with better neurologic and psychiatric outcome. Patients who present with these symptoms and atypical neuroimaging should have a thorough evaluation for CNS germ cell tumors including serum and CSF markers. Clinicians should be aware of these less common presentations to aid in prompt diagnosis and treatment.


Assuntos
Neoplasias Encefálicas/complicações , Transtornos Mentais/etiologia , Neoplasias Embrionárias de Células Germinativas/complicações , Adolescente , Criança , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Estudos Retrospectivos , Adulto Jovem
3.
Oncogene ; 34(29): 3881, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26179456

RESUMO

Correction to: Oncogene (2013) 32, 2304­2314; doi:10.1038/onc. 2012.248; published online 18 June 2012. Since the publication of the above paper, the author listed as C Ryan Miller has requested that the listing of his name be changed to CR Miller.

4.
Oncogene ; 34(3): 394-402, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24469054

RESUMO

Apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) is silenced by promoter methylation in many types of tumors, yet ASC's role in most cancers remains unknown. Here, we show that ASC is highly expressed in a model of medulloblastoma, the most common malignant pediatric brain cancer; ASC is also expressed in human medulloblastomas. Importantly, while ASC deficiency did not affect normal cerebellar development, ASC knockout mice on the Smoothened (ND2:SmoA1) transgenic model of medulloblastoma exhibited a profound reduction in medulloblastoma incidence and a delayed tumor onset. A similar decrease in tumorigenesis with ASC deficiency was also seen in the hGFAP-Cre:SmoM2 mouse model of medulloblastoma. Interestingly, hyperproliferation of the external granule layer (EGL) was comparable at P20 in both wild-type and ASC-deficient SmoA1 mice. However, while the apoptosis and differentiation markers remained unchanged at this age, proliferation makers were decreased, and the EGL was reduced in thickness and area by P60. This reduction in proliferation with ASC deficiency was also seen in isolated SmoA1 cerebellar granule precursor cells in vitro, indicating that the effect of ASC deletion on proliferation was cell autonomous. Interestingly, ASC-deficient SmoA1 cerebella exhibited disrupted expression of genes in the transforming growth factor-ß pathway and increased level of nuclear Smad3. Taken together, these results demonstrate an unexpected role for ASC in Sonic hedgehog-driven medulloblastoma tumorigenesis, thus identifying ASC as a promising novel target for antitumor therapy.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proliferação de Células , Neoplasias Cerebelares/genética , Meduloblastoma/genética , Adolescente , Adulto , Animais , Proteínas Reguladoras de Apoptose/deficiência , Proteínas Adaptadoras de Sinalização CARD , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Criança , Pré-Escolar , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização In Situ , Lactente , Masculino , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos Knockout , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem
5.
Oncogene ; 32(18): 2304-14, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-22710714

RESUMO

Neurogenesis requires negative regulation through differentiation of progenitors or their programmed cell death (PCD). Growth regulation is particularly important in the postnatal cerebellum, where excessive progenitor proliferation promotes medulloblastoma, the most common malignant brain tumor in children. We present evidence that PCD operates alongside differentiation to regulate cerebellar granule neuron progenitors (CGNPs) and to prevent medulloblastoma. Here, we show that genetic deletion of pro-apoptotic Bax disrupts regulation of cerebellar neurogenesis and promotes medulloblastoma formation. In Bax(-/-) mice, the period of neurogenesis was extended into the third week of postnatal life, and ectopic neurons and progenitors collected in the molecular layer of the cerebellum and adjacent tectum. Importantly, genetic deletion of Bax in medulloblastoma-prone ND2:SmoA1 transgenic mice greatly accelerated tumorigenesis. Bax-deficient medulloblastomas exhibited strikingly distinct pathology, with reduced apoptosis, increased neural differentiation and tectal migration. Comparing Bax(+/+) and Bax(-/-) medulloblastomas, we were able to identify upregulation of Bcl-2 and nuclear exclusion of p27 as tumorigenic changes that are required to mitigate the tumor suppressive effect of Bax. Studies on human tumors confirmed the importance of modulating Bax in medulloblastoma pathogenesis. Our results demonstrate that Bax-dependent apoptosis regulates postnatal cerebellar neurogenesis, suppresses medulloblastoma formation and imposes selective pressure on tumors that form. Functional resistance to Bax-mediated apoptosis, required for medulloblastoma tumorigenesis, may be a tumor-specific vulnerability to be exploited for therapeutic benefit.


Assuntos
Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Meduloblastoma/genética , Meduloblastoma/patologia , Neurogênese/genética , Proteína X Associada a bcl-2/genética , Animais , Apoptose/genética , Diferenciação Celular/genética , Movimento Celular/genética , Neoplasias Cerebelares/metabolismo , Cerebelo/citologia , Cerebelo/metabolismo , Cerebelo/patologia , Regulação para Baixo , Meduloblastoma/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptor Smoothened , Células-Tronco/metabolismo , Proteína X Associada a bcl-2/metabolismo
6.
Nanotechnology ; 20(36): 365604, 2009 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-19687541

RESUMO

Large-area free-standing arrays of TiO(2) nanorods and nanotubes were selectively synthesized on transparent conducting indium tin oxide substrates using sol-gel electrophoresis and anodic alumina (AAO) thin film templates. The effect of sol-gel ageing on the growth of TiO(2) was explained, providing a tailored ability to produce nanotubes and nanorods. An annular tungsten base electrode, stemming from the anodization of the AAO template, was found to be crucial to the growth of nanotubes. This was supported by a study of substrate annealing in a reducing atmosphere. The work can be readily adapted for the fabrication of free-standing arrays of other metal, metal oxide, and complex oxide nanorod and nanotube arrays on conducting substrates.

7.
Phys Rev Lett ; 99(13): 131802, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17930575

RESUMO

The neutral B meson pair produced at the Upsilon(4S) should exhibit a nonlocal correlation of the type discussed by Einstein, Podolsky, and Rosen. We measure this correlation using the time-dependent flavor asymmetry of semileptonic B(0) decays, which we compare with predictions from quantum mechanics and two local realistic models. The data are consistent with quantum mechanics, and inconsistent with the other models. Assuming that some B pairs disentangle to produce B(0) and B(0) with definite flavor, we find a decoherent fraction of 0.029 +/ -0.057, consistent with no decoherence.

8.
Phys Rev Lett ; 98(21): 211801, 2007 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-17677763

RESUMO

We report a new measurement of the time-dependent CP-violating parameters in B(0)-->pi(+)pi(-) decays with 535 x 10(6) BB pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider operating at the Upsilon(4S) resonance. We find 1464+/-65 B(0)-->pi(+)pi(-) events and measure the CP-violating parameters S(pipi)=-0.61+/-0.10(stat)+/-0.04(syst) and A(pipi)=+0.55+/-0.08(stat)+/-0.05(syst). We observe large direct CP violation with a significance greater than 5 standard deviations for any S(pipi) value. Using isospin relations, we measure the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle phi(2)=(97+/-11) degrees for the solution consistent with the standard model and exclude the range 11 degrees

9.
Phys Rev Lett ; 98(22): 221602, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17677832

RESUMO

We present a measurement of CP asymmetry using a time-dependent Dalitz plot analysis of B0-->pi+pi-pi0 decays based on a 414 fb(-1) data sample containing 449 x 10(6) BB pairs. The data was collected on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider. Combining our analysis with information on charged B decay modes, we perform a full Dalitz and isospin analysis and obtain a constraint on the CKM angle phi2, 68 degrees < phi2 < 95 degrees as the 68.3% confidence interval for the phi2 solution consistent with the standard model (SM). A large SM-disfavored region also remains.

10.
Phys Rev Lett ; 98(26): 262001, 2007 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-17678081

RESUMO

We report the results of several studies of the Lambda(c)(+)pi(+)pi(-)X final state in continuum e(+)e(-) annihilation data collected by the Belle detector. An analysis of angular distributions in Lambda(c)(2880)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decays strongly favors a Lambda(c)(2880)(+) spin assignment of 5/2 over 3/2 or 1/2. We find evidence for Lambda(c)(2880)(+)-->Sigma(c)(2520)(0,++)pi(+,-) decay and measure the ratio of Lambda(c)(2880)(+) partial widths Gamma(Sigma(c)(2520)pi)/Gamma(Sigma(c)(2455)pi)=0.225+/-0.062+/-0.025. This value favors the Lambda(c)(2880)(+) spin-parity assignment of 5/2(+) over 5/2(-). We also report the first observation of Lambda(c)(2940)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decay and measure Lambda(c)(2880)(+) and Lambda(c)(2940)(+) mass and width parameters. These studies are based on a 553 fb(-1) data sample collected at or near the Upsilon(4S) resonance at the KEKB collider.

11.
Phys Rev Lett ; 99(1): 011801, 2007 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-17678147

RESUMO

The mass of the tau lepton has been measured in the decay mode tau-->3pinutau using a pseudomass technique. The result obtained from 414 fb-1 of data collected with the Belle detector is Mtau=[1776.61+/-0.13(stat)+/-0.35(sys)] MeV/c2. The upper limit on the relative mass difference between positive and negative tau leptons is |Mtau+-Mtau-|/Mtau<2.8 x 10-4 at 90% confidence level.

12.
Phys Rev Lett ; 98(13): 131803, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17501188

RESUMO

We report the first observation of B(0)-->J/psieta decay. These results are obtained from a data sample that contains 449 x10(6) BB[over] pairs accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We observe a signal with a significance of 8.1 sigma and obtain a branching fraction of (9.5+/-1.7(stat)+/-0.8(syst)) x 10(-6).

13.
Phys Rev Lett ; 98(13): 132001, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17501190

RESUMO

We report results of a search for the invisible decay of the Upsilon(1S) via the Upsilon(3S)-->pi+ pi- Upsilon(1S) transition using a data sample of 2.9 fb-1 at the Upsilon(3S) resonance. The data were collected with the Belle detector at the KEKB asymmetric-energy e+ e- collider. No signal is found, and an upper limit for the branching fraction at the 90% confidence level is determined to be B(Upsilon(1S)-->invisible)<2.5 x 10(-3).

14.
Phys Rev Lett ; 98(18): 181804, 2007 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-17501563

RESUMO

Using 449x10(6) BB[over ] pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider, we observe clear signals for B(+)-->K[over ](0)K(+) and B(0)-->K[over ](0)K(0) decays with 5.3sigma and 6.0sigma significance, respectively. We measure the branching fractions B(B(+)-->K[over ](0)K(+))=(1.22(-0.28-0.16)(+0.32+0.13))x10(-6) and B(B(0)-->K[over ](0)K(0))=(0.87(-0.20)(+0.25)+/-0.09)x10(-6), and partial-rate asymmetries A(CP)(B(+)-->K[over ](0)K(+))=0.13(-0.24)(+0.23)+/-0.02 and A(CP)(B(0)-->K[over ](0)K(0))=-0.58(-0.66)(+0.73)+/-0.04. From a simultaneous fit, we also obtain B(B(+)-->K(0)pi(+))=(22.8(-0.7)(+0.8)+/-1.3)x10(-6) and A(CP)(B(+)-->K(0)pi(+))=0.03+/-0.03+/-0.01. The first and second error in the branching fractions and the partial-rate asymmetries are statistical and systematic, respectively. No signal is observed for B(0)-->K(+)K(-) decays, and for this branching fraction, we set an upper limit of 4.1x10(-7) at the 90% confidence level.

15.
Phys Rev Lett ; 98(5): 052001, 2007 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-17358846

RESUMO

The inclusive production of D(s), D(0), and J/psi mesons is studied using a 1.86 fb(-1) data sample collected on the Upsilon(5S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The number of bb events in this Upsilon(5S) data sample is determined. We measure the branching fractions B(Upsilon(5S)-->D(s)X)/2=(23.6+/-1.2+/-3.6)%, B(Upsilon(5S)-->D(0)X)/2=(53.8+/-2.0+/-3.4)%, and B(Upsilon(5S)-->J/psiX)/2=(1.030+/-0.080+/-0.067)%. From the D(s) and D(0) inclusive branching fractions the ratio f(s)=(18.0+/-1.3+/-3.2)% of B(s)(*)B(s)(*) to the total bb quark pair production at the Upsilon(5S) energy is obtained in a model-dependent way.

16.
Phys Rev Lett ; 98(8): 082001, 2007 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-17359087

RESUMO

We report the first observation of a charmoniumlike state recoiling from the J/psi in the inclusive process e+e- -->J/psi+anything at a mass of (3.943+/-0.006+/-0.006) GeV/c{2}. We also observe the decay of this state into D*D[over ] and determine its intrinsic width to be less than 52 MeV/c{2} at the 90% C.L. These results are obtained from a 357 fb{-1} data sample collected with the Belle detector near the Upsilon(4S) resonance, at the KEKB asymmetric-energy e+e- collider.

17.
Phys Rev Lett ; 98(9): 092001, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17359149

RESUMO

We report a measurement of the exclusive e+e- -->D(*)+/-D*-/+ cross section as a function of center-of-mass energy near the D(*)+/-D*-/+ threshold with initial-state radiation. A partial reconstruction technique is used to increase the efficiency and to suppress background. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 547.8 fb(-1).

18.
Phys Rev Lett ; 97(16): 162001, 2006 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-17155385

RESUMO

We report the first observation of two charmed strange baryons that decay into Lambda(c)(+)Kappa(-)pi(+). The broader of the two states is measured to have a mass of 2978.5+/-2.1+/-2.0 MeV/c2 and a width of 43.5+/-7.5+/-7.0 MeV/c2. The mass and width of the narrow state are measured to be 3076.7+/-0.9+/-0.5 MeV/c;{2} and 6.2+/-1.2+/-0.8 MeV/c2, respectively. We also perform a search for the isospin partner states that decay into Lambda(c)(+)Kappa(0)/(s)pi(-) and observe a significant signal at the mass of 3082.8+/-1.8+/-1.5 MeV/c2. The data used for this analysis were accumulated at or near the Upsilon(4S) resonance, using the Belle detector at the e+ e- asymmetric-energy collider KEKB. The integrated luminosity of the data sample used is 461.5 fb(-1).

19.
Phys Rev Lett ; 97(16): 162003, 2006 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-17155387

RESUMO

We study the baryonic charmonium decays of B mesons B+-->etacK+ and B+-->J/psiK+, where the etac and J/psi subsequently decay into a pp[over] or LambdaLambda[over] pair. We measure the J/psi-->pp[over] and LambdaLambda[over] anisotropy parameters alphaB=-0.60+/-0.13+/-0.14 (pp[over]), -0.44+/-0.51+/-0.31 (LambdaLambda[over ]) and compare to results from e;{+}e;{-}-->J/psi formation experiments. We also report the first observation of etac-->LambdaLambda[over]. The measured branching fraction is B(etac-->LambdaLambda[over ])=(0.87(+0.24)/(-0.21)(stat)(+0.09/-0.14) (syst)+/-0.27(PDG))x10-3. This study is based on a 357 fb-1 data sample recorded on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ e- collider.

20.
Phys Rev Lett ; 97(16): 162002, 2006 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-17155386

RESUMO

We report the first observation of a near-threshold enhancement in the D(0)D[over](0)pi(0) system from B-->D(0)D[over](0)pi(0)Kappa decays using a 414 fb(-1) data sample collected at the Upsilon(4S) resonance. The enhancement peaks at a mass M=3875.2+/-0.7(+0.3)/(-1.6) +/-0.8 MeV/c2 and the branching fraction for events in the peak is B(B-->D(0)D[over](0)pi(0)Kappa)=(1.22+/-0.31(+0.23)/(-0.30))x10(-4). The data were collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider.

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