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1.
Phys Rev Lett ; 124(5): 051103, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083934

RESUMO

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

2.
Phys Rev Lett ; 122(5): 051102, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30822017

RESUMO

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5} erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52} erg. A hypothetical population of transient sources has to be more common than 10^{-5} Mpc^{-3} yr^{-1} (5×10^{-8} Mpc^{-3} yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

3.
Phys Rev Lett ; 120(7): 071801, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29542976

RESUMO

We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth's atmosphere at energies as low as ∼5 GeV. That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L/E_{ν} as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies from 5.6 to 56 GeV. We measure Δm_{32}^{2}=2.31_{-0.13}^{+0.11}×10^{-3} eV^{2} and sin^{2}θ_{23}=0.51_{-0.09}^{+0.07}, assuming normal neutrino mass ordering. These results are consistent with, and of similar precision to, those from accelerator- and reactor-based experiments.

4.
Phys Rev Lett ; 117(24): 241101, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-28009216

RESUMO

We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9} GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5} GeV to above 10^{11} GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6} GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5} GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.

5.
Phys Rev Lett ; 117(7): 071801, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27563950

RESUMO

The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous ν_{µ} or ν[over ¯]_{µ} disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos experience a strong Mikheyev-Smirnov-Wolfenstein-resonant oscillation. The exclusion limits extend to sin^{2}2θ_{24}≤0.02 at Δm^{2}∼0.3 eV^{2} at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best-fit value of |U_{e4}|^{2}.

6.
Ann Oncol ; 26(4): 709-714, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25605741

RESUMO

BACKGROUND: Chemotherapy plus bevacizumab is a standard option for first-line treatment in metastatic colorectal cancer (mCRC) patients. We assessed whether no continuation is non-inferior to continuation of bevacizumab after completing first-line chemotherapy. PATIENTS AND METHODS: In an open-label, phase III multicentre trial, patients with mCRC without disease progression after 4-6 months of standard first-line chemotherapy plus bevacizumab were randomly assigned to continuing bevacizumab at a standard dose or no treatment. CT scans were done every 6 weeks until disease progression. The primary end point was time to progression (TTP). A non-inferiority limit for hazard ratio (HR) of 0.727 was chosen to detect a difference in TTP of 6 weeks or less, with a one-sided significance level of 10% and a statistical power of 85%. RESULTS: The intention-to-treat population comprised 262 patients: median follow-up was 36.7 months. The median TTP was 4.1 [95% confidence interval (CI) 3.1-5.4] months for bevacizumab continuation versus 2.9 (95% CI 2.8-3.8) months for no continuation; HR 0.74 (95% CI 0.58-0.96). Non-inferiority could not be demonstrated. The median overall survival was 25.4 months for bevacizumab continuation versus 23.8 months (HR 0.83; 95% CI 0.63-1.1; P = 0.2) for no continuation. Severe adverse events were uncommon in the bevacizumab continuation arm. Costs for bevacizumab continuation were estimated to be ∼30,000 USD per patient. CONCLUSIONS: Non-inferiority could not be demonstrated for treatment holidays versus continuing bevacizumab monotheray, after 4-6 months of standard first-line chemotherapy plus bevacizumab. Based on no impact on overall survival and increased treatment costs, bevacizumab as a single agent is of no meaningful therapeutic value. More efficient treatment approaches are needed to maintain control of stabilized disease following induction therapy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, number NCT00544700.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Bevacizumab/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Irinotecano , Leucovorina/administração & dosagem , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Adulto Jovem
7.
Phys Rev Lett ; 115(8): 081102, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26340177

RESUMO

Results from the IceCube Neutrino Observatory have recently provided compelling evidence for the existence of a high energy astrophysical neutrino flux utilizing a dominantly Southern Hemisphere data set consisting primarily of ν(e) and ν(τ) charged-current and neutral-current (cascade) neutrino interactions. In the analysis presented here, a data sample of approximately 35,000 muon neutrinos from the Northern sky is extracted from data taken during 659.5 days of live time recorded between May 2010 and May 2012. While this sample is composed primarily of neutrinos produced by cosmic ray interactions in Earth's atmosphere, the highest energy events are inconsistent with a hypothesis of solely terrestrial origin at 3.7σ significance. These neutrinos can, however, be explained by an astrophysical flux per neutrino flavor at a level of Φ(E(ν))=9.9(-3.4)(+3.9)×10(-19) GeV(-1) cm(-2) sr(-1) s(-1)(E(ν)/100 TeV(-2), consistent with IceCube's Southern-Hemisphere-dominated result. Additionally, a fit for an astrophysical flux with an arbitrary spectral index is performed. We find a spectral index of 2.2(-0.2)(+0.2), which is also in good agreement with the Southern Hemisphere result.

8.
Br J Cancer ; 110(4): 1008-13, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24366305

RESUMO

BACKGROUND: In colorectal cancer (CRC), tumour budding at the invasion front is associated with lymph node (LN) and distant metastasis. Interestingly, tumour budding can also be detected in biopsies (intratumoural budding; ITB) and may have similar clinical importance. Here we investigate whether ITB in preoperative CRC biopsies can be translated into daily diagnostic practice. METHODS: Preoperative biopsies from 133 CRC patients (no neoadjuvant therapy) underwent immunohistochemistry for pan-cytokeratin marker AE1/AE3. Across all biopsies for each patient, the densest region of buds at × 40 (high-power field; HPF) was identified and buds were counted. RESULTS: A greater number of tumour buds in the biopsy was associated with pT stage (P=0.0143), LN metastasis (P=0.0007), lymphatic (P=0.0065) and venous vessel invasion (P=0.0318) and distant metastasis (cM1) (P=0.0013). Using logistic regression, a 'scale' was developed to estimate the probability of LN and distant metastasis using the number of tumour buds (e.g. 10 buds per HPF: 64% chance of LN metastasis; 30 buds per HPF: 86% chance). Inter-observer agreement for ITB was excellent (intraclass correlation coefficient: 0.813). CONCLUSION: Tumour budding can be assessed in the preoperative biopsy of CRC patients. It is practical, reproducible and predictive of LN and distant metastasis. Intratumoural budding qualifies for further investigation in the prospective setting.


Assuntos
Colo/patologia , Neoplasias do Colo/patologia , Linfonodos/patologia , Neoplasias Retais/patologia , Reto/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Antiporters/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias do Colo/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/cirurgia
9.
Rev Sci Tech ; 33(2): 615-27, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25707188

RESUMO

Although One Health is widely promoted as a more effective approach towards human, animal and ecosystem health, the momentum is still driven largely by health professionals, predominantly from the veterinary sector. While few can doubt the merits of interdisciplinary One Health approaches to tackle complex health problems, operating across the disciplines still presents many challenges. This paper focuses on the contributions of partners from ecology and conservation to One Health approaches, and identifies four broad areas which could act as a focus for practical engagement and bring ecological and conservation objectives more to the forefront of the One Health agenda: i) developing initiatives with shared conservation and health objectives, particularly in and around protected areas and including programmes addressing human reproductive health and mental health; ii) broadening concepts of health to extend beyond indicators of disease to include the assessment of ecological impacts; iii) the integration of ecological and epidemiological monitoring systems within protected areas to support conservation management and wildlife disease surveillance; iv) building partnerships to bring conservation, health, development and animal welfare agencies together to combat threats to global biodiversity and health from the international trade in wildlife and wildlife products.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Saúde Global , Internacionalidade , Animais , Animais Selvagens , Comércio , Humanos , Saúde Pública , Zoonoses
10.
Ecol Lett ; 16(11): 1413, e1-3, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23837659

RESUMO

Packer et al. reported that fenced lion populations attain densities closer to carrying capacity than unfenced populations. However, fenced populations are often maintained above carrying capacity, and most are small. Many more lions are conserved per dollar invested in unfenced ecosystems, which avoid the ecological and economic costs of fencing.


Assuntos
Carnívoros , Conservação dos Recursos Naturais/métodos , Leões , Densidade Demográfica , Animais , Humanos
11.
Ann Oncol ; 24(3): 718-25, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23139259

RESUMO

BACKGROUND: We conducted a randomized, phase II, multicenter study to evaluate the anti-epidermal growth factor receptor (EGFR) mAb panitumumab (P) in combination with chemoradiotherapy (CRT) with standard-dose capecitabine as neoadjuvant treatment for wild-type KRAS locally advanced rectal cancer (LARC). PATIENTS AND METHODS: Patients with wild-type KRAS, T3-4 and/or N+ LARC were randomly assigned to receive CRT with or without P (6 mg/kg). The primary end-point was pathological near-complete or complete tumor response (pNC/CR), defined as grade 3 (pNCR) or 4 (pCR) histological regression by Dworak classification (DC). RESULTS: Forty of 68 patients were randomly assigned to P + CRT and 28 to CRT. pNC/CR was achieved in 21 patients (53%) treated with P + CRT [95% confidence interval (CI) 36%-69%] versus 9 patients (32%) treated with CRT alone (95% CI: 16%-52%). pCR was achieved in 4 (10%) and 5 (18%) patients, and pNCR in 17 (43%) and 4 (14%) patients. In immunohistochemical analysis, most DC 3 cells were not apoptotic. The most common grade ≥3 toxic effects in the P + CRT/CRT arm were diarrhea (10%/6%) and anastomotic leakage (15%/4%). CONCLUSIONS: The addition of panitumumab to neoadjuvant CRT in patients with KRAS wild-type LARC resulted in a high pNC/CR rate, mostly grade 3 DC. The results of both treatment arms exceeded prespecified thresholds. The addition of panitumumab increased toxicity.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/terapia , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Quimiorradioterapia , Análise Mutacional de DNA , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Diarreia/induzido quimicamente , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Panitumumabe , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Neoplasias Retais/genética , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Resultado do Tratamento , Proteínas ras/genética
12.
Phys Rev Lett ; 110(11): 115001, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25166546

RESUMO

This Letter reports on the measurement of the energy loss and the projectile charge states of argon ions at an energy of 4 MeV/u penetrating a fully ionized carbon plasma. The plasma of n(e)≈10(20) cm(-3) and T(e)≈180 eV is created by two laser beams at λ(Las)=532 nm incident from opposite sides on a thin carbon foil. The resulting plasma is spatially homogenous and allows us to record precise experimental data. The data show an increase of a factor of 2 in the stopping power which is in very good agreement with a specifically developed Monte Carlo code, that allows the calculation of the heavy ion beam's charge state distribution and its energy loss in the plasma.

13.
Ann Oncol ; 20(9): 1522-1528, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19465425

RESUMO

BACKGROUND: This multicenter phase II study investigated the efficacy and feasibility of preoperative induction chemotherapy followed by chemoradiation and surgery in patients with esophageal carcinoma. PATIENTS AND METHODS: Patients with locally advanced resectable squamous cell carcinoma or adenocarcinoma of the esophagus received induction chemotherapy with cisplatin 75 mg/m(2) and docetaxel (Taxotere) 75 mg/m(2) on days 1 and 22, followed by radiotherapy of 45 Gy (25 x 1.8 Gy) and concurrent chemotherapy comprising cisplatin 25 mg/m(2) and docetaxel 20 mg/m(2) weekly for 5 weeks, followed by surgery. RESULTS: Sixty-six patients were enrolled at eleven centers and 57 underwent surgery. R0 resection was achieved in 52 patients. Fifteen patients showed complete, 16 patients nearly complete and 26 patients poor pathological remission. Median overall survival was 36.5 months and median event-free survival was 22.8 months. Squamous cell carcinoma and good pathologically documented response were associated with longer survival. Eighty-two percent of all included patients completed neoadjuvant therapy and survived for 30 days after surgery. Dysphagia and mucositis grade 3/4 were infrequent (<9%) during chemoradiation. Five patients (9%) died due to surgical complications. CONCLUSIONS: This neoadjuvant, taxane-containing regimen was efficacious and feasible in patients with locally advanced esophageal cancer in a multicenter, community-based setting and represents a suitable backbone for further investigation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/terapia , Neoplasias Esofágicas/terapia , Terapia Neoadjuvante , Adulto , Idoso , Carcinoma/mortalidade , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Procedimentos Cirúrgicos do Sistema Digestório , Docetaxel , Neoplasias Esofágicas/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Resultado do Tratamento
14.
Ann Oncol ; 19(7): 1288-1292, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18349029

RESUMO

BACKGROUND: To determine the activity and tolerability of adding cetuximab to the oxaliplatin and capecitabine (XELOX) combination in first-line treatment of metastatic colorectal cancer (MCC). PATIENTS AND METHODS: In a multicenter two-arm phase II trial, patients were randomized to receive oxaliplatin 130 mg/m(2) on day 1 and capecitabine 1000 mg/m(2) twice daily on days 1-14 every 3 weeks alone or in combination with standard dose cetuximab. Treatment was limited to a maximum of six cycles. RESULTS: Seventy-four patients with good performance status entered the trial. Objective partial response rates after external review and radiological confirmation were 14% and 41% in the XELOX and in the XELOX + Cetuximab arm, respectively. Stable disease has been observed in 62% and 35% of the patients, with 76% disease control in both arms. Cetuximab led to skin rash in 65% of the patients. The median overall survival was 16.5 months for arm A and 20.5 months for arm B. The median time to progression was 5.8 months for arm A and 7.2 months for arm B. CONCLUSION: Differences in response rates between the treatment arms indicate that cetuximab may improve outcome with XELOX. The correct place of the cetuximab, oxaliplatin and fluoropyrimidine combinations in first-line treatment of MCC has to be assessed in phase III trials.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Antineoplásicos/administração & dosagem , Cetuximab , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Esquema de Medicação , Exantema/induzido quimicamente , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/patologia , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Radiografia , Suíça , Fatores de Tempo , Resultado do Tratamento
15.
Eur Phys J C Part Fields ; 78(10): 831, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30930683

RESUMO

With the observation of high-energy astrophysical neutrinos by the IceCube Neutrino Observatory, interest has risen in models of PeV-mass decaying dark matter particles to explain the observed flux. We present two dedicated experimental analyses to test this hypothesis. One analysis uses 6 years of IceCube data focusing on muon neutrino 'track' events from the Northern Hemisphere, while the second analysis uses 2 years of 'cascade' events from the full sky. Known background components and the hypothetical flux from unstable dark matter are fitted to the experimental data. Since no significant excess is observed in either analysis, lower limits on the lifetime of dark matter particles are derived: we obtain the strongest constraint to date, excluding lifetimes shorter than 10 28 s at 90% CL for dark matter masses above 10 TeV .

16.
J Clin Invest ; 90(6): 2166-74, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1281826

RESUMO

Suramin, a synthetic polysulfonated anionic compound, is known to abrogate the activity of a variety of growth factors that serve as ligands for receptor-class protein-tyrosine kinases. Based on this information, we initially hypothesized that suramin treatment would be associated with decreased tyrosine phosphorylation. Upon testing this hypothesis in prostate cancer cell lines, we found that the most conspicuous effect of suramin was to increase the tyrosine phosphorylation of several distinct proteins. Further analyses indicate that suramin-induced increases in tyrosine phosphorylation represent a generalized, but not universal, phenomenon found in cell lines derived from a variety of human tissues. These rapid and specific suramin-induced alterations represent a novel finding for a non-polypeptide pharmaceutical agent and question the hypothesis that suramin exerts its antitumor action simply by abrogation of growth factor action.


Assuntos
Fosfoproteínas/metabolismo , Neoplasias da Próstata/metabolismo , Suramina/farmacologia , Tirosina/análogos & derivados , Células 3T3 , Animais , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Peso Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Mapeamento de Peptídeos , Fosfoproteínas/química , Fosforilação , Fosfotirosina , Fatores de Tempo , Células Tumorais Cultivadas , Tirosina/metabolismo
17.
Eur Phys J C Part Fields ; 77(10): 692, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31997925

RESUMO

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The ν µ energy unfolding described in this paper is based on data taken with IceCube in its 79-string configuration. A sample of muon neutrino charged-current interactions with a purity of 99.5% was selected by means of a multivariate classification process based on machine learning. The subsequent unfolding was performed using the software Truee. The resulting spectrum covers an E ν -range of more than four orders of magnitude from 125 GeV to 3.2 PeV. Compared to the Honda atmospheric neutrino flux model, the energy spectrum shows an excess of more than 1.9 σ in four adjacent bins for neutrino energies E ν ≥ 177.8 TeV . The obtained spectrum is fully compatible with previous measurements of the atmospheric neutrino flux and recent IceCube measurements of a flux of high-energy astrophysical neutrinos.

18.
Cancer Res ; 55(10): 2122-8, 1995 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-7743512

RESUMO

The propensity of a cell to undergo apoptosis has been proposed to be a determinant for chemotherapy sensitivity that is not directly dependent on specific drug-target interactions. Androgen-independent prostate cancer is typically refractory to cytotoxic drugs, and we tested whether this is due to a loss of the ability to undergo apoptosis. Exposure of the hormone-insensitive and p53-negative human prostate carcinoma cell line PC-3 to 22 microM cisplatin, 1 microM camptothecin, 10 microM tenoposide, 135 nM vincristine, or 10 microM lovastatin for 72 h caused cell death, internucleosomal DNA fragmentation, and morphological changes typical for apoptosis. One microM cycloheximide prevented anticancer drug-induced apoptosis, whereas high concentration (1 mM) of cycloheximide alone induced apoptosis, indicating that protein synthesis was not needed for these cells to undergo apoptosis. Since cycloheximide affected DNA synthesis and proliferation of PC-3 cells, we tested whether the DNA polymerase inhibitor aphidicolin could also suppress drug-induced apoptosis. In contrast to cycloheximide, aphidicolin inhibited only vincristine-induced apoptosis. Cycloheximide prevented drug-induced changes in cell cycle distribution except for vincristine, while aphidicolin led to an accumulation of cells at the G1-S border independent of the drug used. These data indicate that macromolecular synthesis, active cell cycling, and p53 expression are not required for apoptosis to proceed in this system.


Assuntos
Antineoplásicos/farmacologia , Afidicolina/farmacologia , Apoptose/efeitos dos fármacos , Cicloeximida/farmacologia , DNA de Neoplasias/efeitos dos fármacos , Neoplasias da Próstata , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Humanos , Lovastatina/farmacologia , Masculino , Microscopia Eletrônica , Nucleossomos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/ultraestrutura , Células Tumorais Cultivadas
19.
Ther Umsch ; 63(4): 243-8, 2006 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-16689454

RESUMO

Colorectal cancer is the second leading cause of cancer death in Switzerland. The nihilism that dominated the treatment of these patients for decades has been replaced by a measure of enthusiasm, given recent therapeutic advances. New anticancer drugs such as irinotecan and oxaliplatin have changed the standard chemotherapy treatment of metastatic colorectal cancer. However, the real hype has come from molecular targeted therapy. Identification of cellular processes characteristic of colon cancer has permitted therapeutic targeting with favorable therapeutic index. Inhibition of the epidermal growth factor receptor in the clinic has provided proof of principle that interruption of signal transduction cascades in patients has therapeutic potential. Angiogenesis, especially the vascular endothelial growth factor pathway, has been proven to be another highly successful molecular target. In this article, we will review molecular targets, which are under active clinical investigation in colon cancer.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/uso terapêutico , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose , Benzamidas , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Cetuximab , Ensaios Clínicos como Assunto , Ensaios Clínicos Fase II como Assunto , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Sistemas de Liberação de Medicamentos , Receptores ErbB/antagonistas & inibidores , Gefitinibe , Humanos , Mesilato de Imatinib , Indóis/administração & dosagem , Indóis/uso terapêutico , Irinotecano , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Ftalazinas/administração & dosagem , Ftalazinas/uso terapêutico , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Fator de Crescimento Derivado de Plaquetas/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico , Pirróis/administração & dosagem , Pirróis/uso terapêutico , Quinazolinas/uso terapêutico , Quinolonas/uso terapêutico , Receptores do Fator de Crescimento Derivado de Plaquetas/efeitos dos fármacos
20.
Oncogene ; 17(21): 2779-85, 1998 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-9840942

RESUMO

The CDKN2 locus expresses two different mRNA transcripts, designated alpha and beta. The protein product of the alpha transcript is the cell cycle inhibitor and tumour suppressor p16INK4a. The beta transcript is translated in an alternate reading frame (ARF) and in humans encodes a 15 kDa protein (p19ARF). Immunohistochemical and Western analysis of p16INK4a has shown that the protein is downregulated in a significant number of tumours, but less is known on the expression of the p19ARF. We have examined the expression of p16INK4a and p19ARF in resectable non-small cell lung cancer (NSCLC) by immunostaining (n=49) and multiplex RT-PCR (n=28). In order to investigate the mechanism responsible for p16INK4a downregulation, exon 1alpha methylation was analysed in a PCR-based assay. Of 49 tumours examined by immunostaining, 24 and 20 tumours expressed p16INK4a and p19ARF at nil to low levels, respectively. p19ARF was localized primarily to the nuclei of tumour cells, but was also seen to varying degrees in nuclei of lymphocytes, chondrocytes, fibroblasts, and epithelial cells. No tumour with normal p16INK4a had decreased p19ARF expression. Among 16 tumours with nil to low p16INK4a expression, 11 tumours exhibited full methylation of at least one site within exon 1alpha and these tumours showed normal p19ARF expression. In contrast, no methylation of exon 1alpha was observed in five tumours which also lacked p19ARF. In normal lung, p16INK4a and p19ARF were not expressed at detectable levels, the multiplex RT-PCR results were balanced, and sites within exon 1alpha were strongly methylated. In tumours, imbalanced multiplex RT-PCR data (p16INK4a

Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Genes p16 , Genes p53 , Neoplasias Pulmonares/genética , Proteínas de Neoplasias/biossíntese , Proteínas/genética , Proteína Supressora de Tumor p53/biossíntese , Idoso , Animais , Células COS , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclina D1/metabolismo , Metilação de DNA , Éxons/genética , Feminino , Fase G1/genética , Homologia de Genes , Células HeLa , Humanos , Células K562 , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Proteína do Retinoblastoma/biossíntese , Proteína do Retinoblastoma/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteína Supressora de Tumor p14ARF
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