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1.
Phys Rev Lett ; 120(7): 071801, 2018 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-29542976

RESUMEN

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.

2.
Phys Rev Lett ; 117(24): 241101, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-28009216

RESUMEN

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.

3.
Phys Rev Lett ; 117(7): 071801, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27563950

RESUMEN

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}.

4.
Herz ; 41(8): 725-731, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27193907

RESUMEN

AIM: The aim of this study was to analyze differences in the timing of invasive management of patients with high-risk acute coronary syndrome without persistent ST-segment elevation (hr-NSTE-ACS) or myocardial infarction without persistent ST-segment elevation (NSTEMI) between on- and off-hours in a German chest pain unit (CPU). PATIENTS AND METHODS: We retrospectively enrolled 160 NSTEMI patients in the study, who were admitted to two German CPUs in 2013. Patients presenting on weekdays between 8 a.m. and 6 p.m. were compared with patients presenting during off-hours. Data analysis included time intervals from admission to invasive management (goals: for hr-NSTE-ACS, <2 h; for NSTEMI, <24 h) and the resulting guideline adherence. RESULTS: Guideline-adherent timing of an invasive strategy did not differ significantly between the on-hour (6.5 h [3.0-22.0 h], 79.9 %) and off-hour groups (10.5 h [2.0-20.0 h], 75.3 %; p = 0.94), without additional significant differences between admissions during off-hours Monday to Thursday and weekends (10.0 h [2.0-19.0 h], 75.6 % vs. 7.5 h [2.0-20.0 h], 76.2 %; p = 0.96). CONCLUSION: Our exemplary experience in two different German CPUs demonstrates adequate timing of coronary catheterization in over 75 % of cases, irrespective of admission during on- or off-hours. Nationwide validation of our findings by the German CPU registry is mandatory.


Asunto(s)
Atención Posterior/estadística & datos numéricos , Atención Posterior/normas , Revascularización Miocárdica/estadística & datos numéricos , Revascularización Miocárdica/normas , Infarto del Miocardio sin Elevación del ST/diagnóstico , Infarto del Miocardio sin Elevación del ST/cirugía , Anciano , Dolor en el Pecho/diagnóstico , Dolor en el Pecho/epidemiología , Dolor en el Pecho/prevención & control , Comorbilidad , Servicios Médicos de Urgencia/normas , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Alemania/epidemiología , Adhesión a Directriz/estadística & datos numéricos , Unidades Hospitalarias/normas , Unidades Hospitalarias/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio sin Elevación del ST/epidemiología , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
5.
Herz ; 41(2): 151-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26407695

RESUMEN

AIM: This study aimed to analyze guideline adherence in the timing of invasive management for myocardial infarction without persistent ST-segment elevation (NSTEMI) in two exemplary German centers, comparing an urban university maximum care facility and a rural regional primary care facility. METHODS: All patients diagnosed as having NSTEMI during 2013 were retrospectively enrolled in two centers: (1) site I, a maximum care center in an urban university setting, and (b) site II, a primary care center in a rural regional care setting. Data acquisition included time intervals from admission to invasive management, risk criteria, rate of intervention, and medical therapy. RESULTS: The median time from admission to coronary angiography was 12.0 h (site I) or 17.5 h (site II; p = 0.17). Guideline-adherent timing was achieved in 88.1 % (site I) or 82.9 % (site II; p = 0.18) of cases. Intervention rates were high in both sites (site I-75.5 % vs. site II-75.3 %; p = 0.85). Adherence to recommendations of medical therapy was high and comparable between the two sites. CONCLUSION: In NSTEMI or high-risk acute coronary syndromes without persistent ST-segment elevation, guideline-adherent timing of invasive management was achieved in about 85 % of cases, and was comparable between urban maximum and rural primary care settings. Validation by the German Chest Pain Unit Registry including outcome analysis is required.


Asunto(s)
Centros Médicos Académicos/estadística & datos numéricos , Adhesión a Directriz/estadística & datos numéricos , Hospitales Urbanos/estadística & datos numéricos , Infarto del Miocardio/mortalidad , Infarto del Miocardio/terapia , Servicios de Salud Rural/estadística & datos numéricos , Tiempo de Tratamiento/estadística & datos numéricos , Centros Médicos Académicos/normas , Anciano , Biomarcadores/sangre , Dolor en el Pecho/diagnóstico , Dolor en el Pecho/mortalidad , Dolor en el Pecho/terapia , Europa (Continente) , Femenino , Alemania/epidemiología , Hospitales Urbanos/normas , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/epidemiología , Prevalencia , Atención Primaria de Salud/normas , Atención Primaria de Salud/estadística & datos numéricos , Estudios Retrospectivos , Servicios de Salud Rural/normas , Infarto del Miocardio con Elevación del ST , Tasa de Supervivencia , Tiempo de Tratamiento/normas , Resultado del Tratamiento , Troponina/sangre
6.
Phys Rev Lett ; 115(8): 081102, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26340177

RESUMEN

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.

7.
Phys Rev Lett ; 114(17): 171102, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25978221

RESUMEN

A diffuse flux of astrophysical neutrinos above 100 TeV has been observed at the IceCube Neutrino Observatory. Here we extend this analysis to probe the astrophysical flux down to 35 TeV and analyze its flavor composition by classifying events as showers or tracks. Taking advantage of lower atmospheric backgrounds for showerlike events, we obtain a shower-biased sample containing 129 showers and 8 tracks collected in three years from 2010 to 2013. We demonstrate consistency with the (fe:fµ:fτ)⊕≈(1:1:1)⊕ flavor ratio at Earth commonly expected from the averaged oscillations of neutrinos produced by pion decay in distant astrophysical sources. Limits are placed on nonstandard flavor compositions that cannot be produced by averaged neutrino oscillations but could arise in exotic physics scenarios. A maximally tracklike composition of (0:1:0)⊕ is excluded at 3.3σ, and a purely showerlike composition of (1:0:0)⊕ is excluded at 2.3σ.

8.
Phys Rev Lett ; 113(10): 101101, 2014 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-25238345

RESUMEN

A search for high-energy neutrinos interacting within the IceCube detector between 2010 and 2012 provided the first evidence for a high-energy neutrino flux of extraterrestrial origin. Results from an analysis using the same methods with a third year (2012-2013) of data from the complete IceCube detector are consistent with the previously reported astrophysical flux in the 100 TeV-PeV range at the level of 10(-8) GeV cm-2 s-1 sr-1 per flavor and reject a purely atmospheric explanation for the combined three-year data at 5.7σ. The data are consistent with expectations for equal fluxes of all three neutrino flavors and with isotropic arrival directions, suggesting either numerous or spatially extended sources. The three-year data set, with a live time of 988 days, contains a total of 37 neutrino candidate events with deposited energies ranging from 30 to 2000 TeV. The 2000-TeV event is the highest-energy neutrino interaction ever observed.

9.
J Postgrad Med ; 60(4): 403-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25370552

RESUMEN

Tumor-to-tumor metastasis (T2Tmets) is an established entity but often overlooked and underdiagnosed. Merely 84 such cases are reported in literature till date. The authors here describe a 65-year-old man presenting with first episode of focal seizure and incidentally turned out to be a case of adenocarcinoma of lung metastatic to a meningioma. The diagnosis of T2Tmets was based solely on histopathological criteria. Recent advent of brain imaging revolutionized its diagnosis and it has moved from the realm of thologists to that of radiologists. In our case, diagnosis was also established by immunohistochemistry.


Asunto(s)
Adenocarcinoma/secundario , Neoplasias Pulmonares/patología , Neoplasias Meníngeas/secundario , Meningioma/patología , Meningioma/secundario , Adenocarcinoma/diagnóstico , Adenocarcinoma del Pulmón , Anciano , Humanos , Inmunohistoquímica , Perdida de Seguimiento , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/secundario , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/cirugía , Tomografía Computarizada por Rayos X
10.
Phys Rev Lett ; 110(13): 131302, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23581307

RESUMEN

We have performed a search for muon neutrinos from dark matter annihilation in the center of the Sun with the 79-string configuration of the IceCube neutrino telescope. For the first time, the DeepCore subarray is included in the analysis, lowering the energy threshold and extending the search to the austral summer. The 317 days of data collected between June 2010 and May 2011 are consistent with the expected background from atmospheric muons and neutrinos. Upper limits are set on the dark matter annihilation rate, with conversions to limits on spin-dependent and spin-independent scattering cross sections of weakly interacting massive particles (WIMPs) on protons, for WIMP masses in the range 20-5000 GeV/c2. These are the most stringent spin-dependent WIMP-proton cross section limits to date above 35 GeV/c2 for most WIMP models.

11.
Phys Rev Lett ; 111(8): 081801, 2013 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-24010427

RESUMEN

We present the first statistically significant detection of neutrino oscillations in the high-energy regime (>20 GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010 and 2011. This measurement is made possible by the low-energy threshold of the DeepCore detector (~20 GeV) and benefits from the use of the IceCube detector as a veto against cosmic-ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20-100 GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV-10 TeV) was extracted from IceCube data to constrain systematic uncertainties. The disappearance of low-energy upward-going muon neutrinos was observed, and the nonoscillation hypothesis is rejected with more than 5σ significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters |Δm(32)(2)|=(2.3(-0.5)(+0.6))×10(-3) eV(2) and sin(2)(2θ(23))>0.93, and maximum mixing is favored.

12.
Phys Rev Lett ; 111(2): 021103, 2013 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-23889381

RESUMEN

We report on the observation of two neutrino-induced events which have an estimated deposited energy in the IceCube detector of 1.04±0.16 and 1.14±0.17 PeV, respectively, the highest neutrino energies observed so far. These events are consistent with fully contained particle showers induced by neutral-current ν(e,µ,τ) (ν(e,µ,τ)) or charged-current ν(e) (ν(e)) interactions within the IceCube detector. The events were discovered in a search for ultrahigh energy neutrinos using data corresponding to 615.9 days effective live time. The expected number of atmospheric background is 0.082±0.004(stat)(-0.057)(+0.041)(syst). The probability of observing two or more candidate events under the atmospheric background-only hypothesis is 2.9×10(-3) (2.8σ) taking into account the uncertainty on the expected number of background events. These two events could be a first indication of an astrophysical neutrino flux; the moderate significance, however, does not permit a definitive conclusion at this time.

13.
Phys Rev Lett ; 110(15): 151105, 2013 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-25167245

RESUMEN

We report the first measurement of the atmospheric electron neutrino flux in the energy range between approximately 80 GeV and 6 TeV, using data recorded during the first year of operation of IceCube's DeepCore low-energy extension. Techniques to identify neutrinos interacting within the DeepCore volume and veto muons originating outside the detector are demonstrated. A sample of 1029 events is observed in 281 days of data, of which 496±66(stat)±88(syst) are estimated to be cascade events, including both electron neutrino and neutral current events. The rest of the sample includes residual backgrounds due to atmospheric muons and charged current interactions of atmospheric muon neutrinos. The flux of the atmospheric electron neutrinos is consistent with models of atmospheric neutrinos in this energy range. This constitutes the first observation of electron neutrinos and neutral current interactions in a very large volume neutrino telescope optimized for the TeV energy range.

14.
Br J Cancer ; 104(8): 1270-7, 2011 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-21407219

RESUMEN

BACKGROUND: Bevacizumab (Bev), a monoclonal antibody to vascular endothelial growth factor (VEGF), is used in combination with chemotherapy for the treatment of metastatic colorectal cancer (CRC). The effects of Bev on angiogenesis have been well described, but the direct effect of Bev on tumour cells is unknown. This study was carried out to determine the molecular and phenotypic changes in CRC cells after chronic Bev exposure in vitro. METHODS: Human CRC cell lines were chronically exposed (3 months) to Bev in vitro to develop Bev-adapted (Bev-A) cell lines. Vascular endothelial growth factor family members were determined by reverse transcription-polymerase chain reaction and western blotting. Migration and invasion was determined using standard in vitro assays. Intravenous injection of tumour cells was carried out to evaluate metastatic potential in mice. RESULTS: Bevacizumab-adapted cells were found to be more migratory and invasive than control cells (P<0.001). Bevacizumab-adapted cells showed higher levels of VEGF-A, -B, -C, placental growth factor (PlGF), VEGF receptor-1 (VEGFR-1) and phosphorylation of VEGFR-1. Furthermore, treatment with SU5416, a VEGFR protein tyrosine kinase inhibitor, led to significantly decreased cell migration in vitro (P<0.001). Bevacizumab-adapted cells were more metastatic in vivo (P<0.05). CONCLUSION: Chronic exposure of CRC cells to Bev (1) increased expression of VEGF-A, -B, -C, PlGF, VEGFR-1 and VEGFR-1 phosphorylation, (2) increased tumour cell migration and invasion, and (3) metastatic potential in vivo. Our study shows the functional significance of autocrine VEGF signalling in CRC cells.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Carcinoma/patología , Movimiento Celular/efectos de los fármacos , Neoplasias Colorrectales/patología , Resistencia a Antineoplásicos/fisiología , Animales , Anticuerpos Monoclonales Humanizados , Antineoplásicos/farmacología , Bevacizumab , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacos , Células HCT116 , Humanos , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Trasplante Heterólogo
15.
Br J Cancer ; 105(11): 1759-67, 2011 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-22045189

RESUMEN

BACKGROUND: Recent studies suggest that cancer stem cells (CSCs) mediate chemoresistance, but interestingly, only a small percentage of cells in a resistant tumour are CSCs; this suggests that non-CSCs survive by other means. We hypothesised that chemoresistant colorectal cancer (CRC) cells generate soluble factors that enhance survival of chemonaive tumour cells. METHODS: Chemoresistant CRC cells were generated by serial passage in oxaliplatin (Ox cells). Conditioned media (CM) was collected from parental and oxaliplatin-resistant (OxR) cells. CRC cells were treated with CM and growth and survival were assessed. Tumour growth rates were determined in nude mice after cells were treated with CM. Mass spectrometry (MS) identified proteins in CM. Reverse phase protein microarray assays determined signalling effects of CM in parental cells. RESULTS: Oxaliplatin-resistant CM increased survival of chemo-naive cells. CSC CM also increased growth of parental cells. Parental and OxR mixed tumours grew larger than tumours composed of parental or OxR cells alone. Mass spectrometry detected unique survival-promoting factors in OxR CM compared with parental CM. Cells treated with OxR CM demonstrated early phosphorylation of EGFR and MEK1, with later upregulation of total Akt .We identified progranulin as a potential mediator of chemoresistance. CONCLUSION: Chemoresistant tumour cells and CSCs may promote resistance through soluble factors that mediate survival in otherwise chemosensitive tumour cells.


Asunto(s)
Efecto Espectador/fisiología , Neoplasias Colorrectales/patología , Células Madre Neoplásicas/patología , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Medios de Cultivo , Resistencia a Antineoplásicos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Células HCT116 , Células HT29 , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , MAP Quinasa Quinasa 1/genética , MAP Quinasa Quinasa 1/metabolismo , Masculino , Espectrometría de Masas/métodos , Ratones , Ratones Desnudos , Análisis por Micromatrices/métodos , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Compuestos Organoplatinos/farmacología , Oxaliplatino , Fosforilación , Progranulinas , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Regulación hacia Arriba
16.
Phys Rev Lett ; 106(14): 141101, 2011 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-21561178

RESUMEN

IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18) eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence.

17.
Herz ; 36(6): 531-8, 2011 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-21858546

RESUMEN

Malperfusion of the thoracoabdominal aorta and its side branches is a common complication of aortic dissection, often proving fatal. Vital organ malperfusion accompanying acute aortic dissection is a major cause of mortality and morbidity and requires timely reperfusion of the ischemic organs as well as adequate management of the aortic dissection. Ischemic damage to vital organs supplied by the thoracoabdominal aorta greatly increases the overall risk of aortic dissection. As initial symptoms may be subtle, malperfusion tends to be recognized late, and therefore accounts for a considerable percentage of fatalities.Effective reperfusion is not readily achieved by central aortic surgery alone in a certain number of patients. Various strategies have been used, including entry closure by central aortic surgery or stent grafting, surgical or catheter fenestration, bypass grafting and percutaneous stenting.Endovascular bare-metal stent placement is an attractive and promising treatment option since it is readily available, is less invasive and presents fewer risks to the patient.


Asunto(s)
Aneurisma de la Aorta Torácica/diagnóstico , Disección Aórtica/diagnóstico , Isquemia/diagnóstico , Abdomen Agudo/etiología , Abdomen Agudo/mortalidad , Abdomen Agudo/cirugía , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/mortalidad , Lesión Renal Aguda/cirugía , Anciano , Disección Aórtica/mortalidad , Disección Aórtica/cirugía , Angioplastia , Aneurisma de la Aorta Torácica/mortalidad , Aneurisma de la Aorta Torácica/cirugía , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/mortalidad , Arteriopatías Oclusivas/cirugía , Implantación de Prótesis Vascular , Causas de Muerte , Arteria Celíaca , Ecocardiografía Transesofágica , Extremidades/irrigación sanguínea , Femenino , Humanos , Isquemia/cirugía , Riñón/irrigación sanguínea , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/mortalidad , Isquemia Miocárdica/cirugía , Factores de Riesgo , Stents , Tomografía Computarizada por Rayos X , Vísceras/irrigación sanguínea
18.
Clin Anat ; 24(3): 362-71, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21433083

RESUMEN

This article reviews the attributes of the human surrogates most commonly used in injury biomechanics research. In particular, the merits of human cadavers, human volunteers, animals, dummies, and computational models are assessed relative to their ability to characterize the living human response and injury in an impact environment. Although data obtained from these surrogates have enabled biomechanical engineers and designers to develop effective injury countermeasures for occupants and pedestrians involved in crashes, the magnitude of the traffic safety problem necessitates expanded efforts in research and development. This article makes the case that while there are limitations and challenges associated with any particular surrogate, each provides a critical and necessary component in the continued quest to reduce crash-related injuries and fatalities.


Asunto(s)
Accidentes de Tránsito , Fenómenos Biomecánicos/fisiología , Maniquíes , Heridas y Lesiones/fisiopatología , Cadáver , Simulación por Computador , Humanos , Modelos Animales , Modelos Biológicos , Traumatología/métodos
19.
J Comb Chem ; 12(1): 100-10, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20000618

RESUMEN

An efficient and practical method has been manifested for the diversity-oriented synthesis of quinolines via Friedländer annulation reaction for the generation of a wide range of structurally interesting and pharmacologically significant compounds by using ceric ammonium nitrate as a catalyst (10 mol %) at ambient temperature in 45 min. A variety of functional groups are introduced at various positions of the quinoline moiety, and further the diversity of the core skeleton was expanded at R(1) and R(2) positions by the synthesis of various hybrids. Initial screening of the compounds for cytotoxicity against a series of cancer cell lines showed promising results.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Quinolinas/síntesis química , Antineoplásicos/química , Camptotecina/farmacología , Catálisis , Línea Celular Tumoral , Cerio/química , Etopósido/farmacología , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Estructura Molecular , Factores de Tiempo
20.
Indian Heart J ; 70(6): 911-914, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30580865

RESUMEN

The recently published Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) trial evaluated the hypothesis that rivaroxaban alone or in combination with aspirin would be more effective than aspirin alone for secondary prevention. In India, stable cardiovascular disease occurs in a much younger age group relative to the rest of the world. Our critical analysis of COMPASS trial showed that the younger age group appeared to derive greater benefit from the rivaroxaban+aspirin combination (relative to aspirin alone) as seen with number needed to treat metrics as compared to the older age group.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Fibrinolíticos/uso terapéutico , Medición de Riesgo , Prevención Secundaria/métodos , Terapia Trombolítica/métodos , Enfermedades Cardiovasculares/epidemiología , Humanos , India/epidemiología , Morbilidad/tendencias , Números Necesarios a Tratar
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