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1.
Phys Rev Lett ; 126(7): 071103, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33666466

RESUMEN

ANITA's fourth long-duration balloon flight in 2016 detected 29 cosmic-ray (CR)-like events on a background of 0.37_{-0.17}^{+0.27} anthropogenic events. CRs are mainly seen in reflection off the Antarctic ice sheets, creating a phase-inverted waveform polarity. However, four of the below-horizon CR-like events show anomalous noninverted polarity, a p=5.3×10^{-4} chance if due to background. All anomalous events are from locations near the horizon; ANITA-IV observed no steeply upcoming anomalous events similar to the two such events seen in prior flights.

2.
Phys Rev Lett ; 121(16): 161102, 2018 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-30387639

RESUMEN

We report on an upward traveling, radio-detected cosmic-ray-like impulsive event with characteristics closely matching an extensive air shower. This event, observed in the third flight of the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload, is consistent with a similar event reported in a previous flight. These events could be produced by the atmospheric decay of an upward-propagating τ lepton produced by a ν_{τ} interaction, although their relatively steep arrival angles create tension with the standard model neutrino cross section. Each of the two events have a posteriori background estimates of ≲10^{-2} events. If these are generated by τ-lepton decay, then either the charged-current ν_{τ} cross section is suppressed at EeV energies, or the events arise at moments when the peak flux of a transient neutrino source was much larger than the typical expected cosmogenic background neutrinos.

3.
Epidemiol Infect ; 145(11): 2374-2381, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28641590

RESUMEN

Measles elimination relies on vaccination programmes. In Japan, a major outbreak started in 2007. In response, 5-year two-dose catch-up vaccination programme was initiated in April 2008 for children 13-16-years-old. In this study, we analysed the epidemic curves, incidence rates for each age group, virus genotype, vaccination coverage and ratio of measles gelatin particle agglutination (PA) antibody using surveillance data for 2008-2015. Monthly case counts markedly decreased as vaccination coverage increased. D5, which is the endemic virus type, disappeared after 2011, with the following epidemic caused by imported viruses. Most cases were confirmed to have a no-dose or single-dose vaccination status. Although the incidence rate among all age groups ⩾5-years-old decreased during the study period, for children <5-years-old, the incidence rate remained relatively high and increased in 2014. The ratio of PA antibody (⩾1:128 titres) increased for the majority of age groups, but with a decrease for specific age groups: the 0-5 months and the 2-4, 14, 19 and most of the 26-55- and the 60-year-old groups (-1 to -9%). This seems to be the result of higher vaccination coverage, which would result in decreasing natural immunity booster along with decreasing passive immunity in infants whose mothers did not have the natural immunity booster. The 20-29- and 30-39-year-old age groups had higher number of cases, suggesting that vaccination within these age groups might be important for eliminating imported viruses.


Asunto(s)
Erradicación de la Enfermedad , Epidemias , Programas de Inmunización , Sarampión/epidemiología , Sarampión/prevención & control , Vacunación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Japón/epidemiología , Masculino , Sarampión/virología , Vacuna Antisarampión/administración & dosificación , Persona de Mediana Edad , Adulto Joven
4.
Epidemiol Infect ; 145(6): 1183-1192, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28091341

RESUMEN

We investigated the relationship between epidemics and soil radiation through an exploratory study using sentinel surveillance data (individuals aged <20 years) during the last three epidemic seasons of influenza and norovirus in Japan. We used a spatial analysis method of a geographical information system (GIS). We mapped the epidemic spreading patterns from sentinel incidence rates. We calculated the average soil radiation [dm (µGy/h)] for each sentinel site using data on uranium, thorium, and potassium oxide in the soil and examined the incidence rate in units of 0·01 µGy/h. The correlations between the incidence rate and the average soil radiation were assessed. Epidemic clusters of influenza and norovirus infections were observed in areas with relatively high radiation exposure. A positive correlation was detected between the average incidence rate and radiation dose, at r = 0·61-0·84 (P < 0·01) for influenza infections and r = 0·61-0·72 (P < 0·01) for norovirus infections. An increase in the incidence rate was found between areas with radiation exposure of 0 < dm < 0·01 and 0·15 ⩽ dm < 0·16, at 1·80 [95% confidence interval (CI) 1·47-2·12] times higher for influenza infection and 2·07 (95% CI 1·53-2·61) times higher for norovirus infection. Our results suggest a potential association between decreased immunity and irradiation because of soil radiation. Further studies on immunity in these epidemic-prone areas are desirable.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Gripe Humana/epidemiología , Radiación , Vigilancia de Guardia , Suelo/química , Adolescente , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Japón/epidemiología , Masculino , Norovirus/aislamiento & purificación , Orthomyxoviridae/aislamiento & purificación , Óxidos/análisis , Compuestos de Potasio/análisis , Torio/análisis , Topografía Médica , Uranio/análisis , Adulto Joven
5.
Phys Rev Lett ; 117(7): 071101, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27563945

RESUMEN

We report on four radio-detected cosmic-ray (CR) or CR-like events observed with the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload. Two of the four were previously identified as stratospheric CR air showers during the ANITA-I flight. A third stratospheric CR was detected during the ANITA-II flight. Here, we report on characteristics of these three unusual CR events, which develop nearly horizontally, 20-30 km above the surface of Earth. In addition, we report on a fourth steeply upward-pointing ANITA-I CR-like radio event which has characteristics consistent with a primary that emerged from the surface of the ice. This suggests a possible τ-lepton decay as the origin of this event, but such an interpretation would require significant suppression of the standard model τ-neutrino cross section.

6.
Epidemiol Infect ; 144(12): 2561-7, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27301793

RESUMEN

Norovirus (NoV) epidemics normally peak in December in Japan; however, the peak in the 2009-2010 season was delayed until the fourth week of January 2010. We suspected intensive hand hygiene that was conducted for a previous pandemic influenza in 2009 as the cause of this delay. We analysed the NoV epidemic trend, based on national surveillance data, and its associations with monthly output data for hand hygiene products, including alcohol-based skin antiseptics and hand soap. The delayed peak in the NoV incidence in the 2009-2010 season had the lowest number of recorded cases of the five seasons studied (2006-2007 to 2010-2011). GII.4 was the most commonly occurring genotype. The monthly relative risk of NoV and monthly output of both alcohol-based skin antiseptics and hand soap were significantly and negatively correlated. Our findings suggest an association between hand hygiene using these products and prevention of NoV transmission.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Gastroenteritis/epidemiología , Desinfección de las Manos , Desinfectantes para las Manos/uso terapéutico , Gripe Humana/epidemiología , Norovirus/fisiología , Pandemias , Infecciones por Caliciviridae/virología , Gastroenteritis/virología , Genotipo , Higiene de las Manos/estadística & datos numéricos , Humanos , Gripe Humana/prevención & control , Gripe Humana/virología , Japón/epidemiología , Norovirus/genética , Estaciones del Año
7.
Rev Sci Instrum ; 87(2): 021301, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26931826

RESUMEN

We present the development of the miniTimeCube (mTC), a novel compact neutrino detector. The mTC is a multipurpose detector, aiming to detect not only neutrinos but also fast/thermal neutrons. Potential applications include the counterproliferation of nuclear materials and the investigation of antineutrino short-baseline effects. The mTC is a plastic 0.2% (10)B-doped scintillator (13 cm)(3) cube surrounded by 24 Micro-Channel Plate (MCP) photon detectors, each with an 8 × 8 anode totaling 1536 individual channels/pixels viewing the scintillator. It uses custom-made electronics modules which mount on top of the MCPs, making our detector compact and able to both distinguish different types of events and reject noise in real time. The detector is currently deployed and being tested at the National Institute of Standards and Technology Center for Neutron Research nuclear reactor (20 MWth) in Gaithersburg MD. A shield for further tests is being constructed, and calibration and upgrades are ongoing. The mTC's improved spatiotemporal resolution will allow for determination of incident particle directions beyond previous capabilities.

8.
Epidemiol Infect ; 143(3): 522-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24780387

RESUMEN

We studied the spatial trend of norovirus (NoV) epidemics using sentinel gastroenteritis surveillance data for patients aged <15 years (n = 140) in the Tokyo area for the 2006-2007 to 2008-2009 seasons utilizing the kriging method of geographical information system (GIS). This is the first study of the spreading pattern of NoV epidemics using sentinel surveillance data. Correlations of sentinel cases between the seasons and with demographic data were examined to identify the trend and related factors. A similar pattern of diffusion was observed over the seasons, and its mean correlation between seasons was significantly high. A higher number of cases were found in the peripheral area, which surrounds the most populated central area, and showed a correlation with the ratio of the children population (r = 0·321, P < 0·01) and the ratio of residents in larger families (r = 0·263, P < 0·01). While NoV susceptibility remained, the results suggest a transmission route in the local community as a possible epidemic factor. Prevention with focus on the peripheral area is desirable.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Epidemias , Norovirus/aislamiento & purificación , Adolescente , Infecciones por Caliciviridae/virología , Niño , Preescolar , Demografía , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estaciones del Año , Análisis Espacio-Temporal , Tokio/epidemiología
9.
Phys Rev Lett ; 105(15): 151101, 2010 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-21230887

RESUMEN

We report the observation of 16 cosmic ray events with a mean energy of 1.5 × 10¹9 eV via radio pulses originating from the interaction of the cosmic ray air shower with the Antarctic geomagnetic field, a process known as geosynchrotron emission. We present measurements in the 300-900 MHz range, which are the first self-triggered, first ultrawide band, first far-field, and the highest energy sample of cosmic ray events collected with the radio technique. Their properties are inconsistent with current ground-based geosynchrotron models. The emission is 100% polarized in the plane perpendicular to the projected geomagnetic field. Fourteen events are seen to have a phase inversion due to reflection of the radio beam off the ice surface, and two additional events are seen directly from above the horizon. Based on a likelihood analysis, we estimate angular pointing precision of order 2° for the event arrival directions.

10.
Phys Rev Lett ; 103(5): 051103, 2009 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-19792479

RESUMEN

We report initial results of the first flight of the Antarctic Impulsive Transient Antenna (ANITA-1) 2006-2007 Long Duration Balloon flight, which searched for evidence of a diffuse flux of cosmic neutrinos above energies of E(nu) approximately 3 x 10(18) eV. ANITA-1 flew for 35 days looking for radio impulses due to the Askaryan effect in neutrino-induced electromagnetic showers within the Antarctic ice sheets. We report here on our initial analysis, which was performed as a blind search of the data. No neutrino candidates are seen, with no detected physics background. We set model-independent limits based on this result. Upper limits derived from our analysis rule out the highest cosmogenic neutrino models. In a background horizontal-polarization channel, we also detect six events consistent with radio impulses from ultrahigh energy extensive air showers.

11.
Phys Rev Lett ; 99(17): 171101, 2007 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-17995315

RESUMEN

We report on observations of coherent, impulsive radio Cherenkov radiation from electromagnetic showers in solid ice. This is the first observation of the Askaryan effect in ice. As part of the complete validation process for the ANITA experiment, we performed an experiment at the Stanford Linear Accelerator Center in June 2006 using a 7.5 metric ton ice target. We measure for the first time the large-scale angular dependence of the radiation pattern, a major factor in determining the solid-angle acceptance of ultrahigh-energy neutrino detectors.

12.
Phys Rev Lett ; 96(17): 171101, 2006 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-16712284

RESUMEN

We report new limits on cosmic neutrino fluxes from the test flight of the Antarctic Impulsive Transient Antenna (ANITA) experiment, which completed an 18.4 day flight of a prototype long-duration balloon payload, called ANITA-lite, in early 2004. We search for impulsive events that could be associated with ultrahigh energy neutrino interactions in the ice and derive limits that constrain several models for ultrahigh energy neutrino fluxes and rule out the long-standing -burst model.

13.
Cancer Gene Ther ; 13(3): 242-52, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16179928

RESUMEN

An adenovirus (Adv) retaining normal E1A but lacking the 55 kDa E1B protein replicates preferentially in TP53-deficient cancer cells including pancreatic cancer cell lines, resulting in the oncolysis of the tumor. When tumor cells are exposed to hypoxia, hypoxia-inducible factor-1alpha (HIF-1alpha) is stabilized and activated to promote the transcription of several genes such as vascular endothelial growth factor (VEGF), but in the presence of E1A hypoxia-induced VEGF m-RNA synthesis is inhibited by E1A binding to p300. In this study, we demonstrated that the cancer cells infected with a mutant Adv in which the p300 binding site in E1A was partially deleted induced a higher expression level of VEGF as compared to those of Adv with normal E1A. An immunoprecipitation study for E1A confirmed that mutant E1A had a reduced binding capacity for p300. Although the expressions of HIF-1alpha m-RNA were almost the same in both cancer cells infected with the mutant Adv and those with the wild Adv, the amount of HIF-1alpha protein in cancer cells infected with the wild E1A Adv was lower than in those infected with the mutant E1A type Adv. In vivo, in contrast to the angiogenesis treated with mutant E1A, wild-E1A inhibited tumor angiogenesis significantly. These results suggested that E1A suppressed the production of VEGF and inhibited tumor angiogenesis by binding with p300, resulting in the inhibition of the HIF-1alpha-mediated transcription of genes through binding to HRE. This study demonstrates, for the first time, the effect of an oncolytic replication-competent Adv in inhibiting tumor angiogenesis.


Asunto(s)
Adenoviridae/fisiología , Proteínas E1A de Adenovirus/genética , Neovascularización Patológica/prevención & control , Viroterapia Oncolítica , Neoplasias Pancreáticas/irrigación sanguínea , Replicación Viral , Animales , Sitios de Unión , Hipoxia de la Célula , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Ratones , Ratones SCID , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Regiones Promotoras Genéticas , ARN Mensajero , Transcripción Genética , Transfección , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factores de Transcripción p300-CBP/metabolismo
14.
Rocz Akad Med Bialymst ; 50: 101-5, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16358947

RESUMEN

Acute pancreatitis is an autodigestive disease, of which protease inhibition has been the focus of experimental and clinical research. Different from Europe and the United States, protease inhibitors are often applied in the treatment of acute pancreatitis in Japan. However, in clinical settings, the effect of protease inhibitors on acute pancreatitis is still controversial. Continuous Regional Arterial Infusion (CRAI) of protease inhibitors and antibiotics therapy were developed in Japan and it has been demonstrated that CRAI therapy has beneficial effects on severe acute necrotizing pancreatitis. In the Japanese clinical guidelines for the treatment of acute pancreatitis, published in 2003, CRAI therapy is still classified as a special therapy. However, a Randomized Controlled Trial for CRAI therapy has started and CRAI therapy is expected to become a new standard therapy for severe acute pancreatitis. CRAI therapy is aimed at preventing the progression of pancreatic inflammation and pancreatic infection. CRAI therapy can decrease the mortality rate and the frequency of pancreatic infection in severe acute pancreatitis, but it should be started as soon as possible after the onset of acute pancreatitis.


Asunto(s)
Antibacterianos/administración & dosificación , Infusiones Intraarteriales , Pancreatitis Aguda Necrotizante/tratamiento farmacológico , Inhibidores de Serina Proteinasa/administración & dosificación , Humanos , Tomografía Computarizada por Rayos X
15.
Eur Surg Res ; 37(4): 228-34, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16260873

RESUMEN

The interaction of immature dendritic cells (DC) with irradiated pancreatic cancer cells was examined. Flow cytometric analysis using annexin V and propidium iodide revealed that ionizing radiation (25-35 Gy X-ray) induced both apoptosis and necrosis in pancreatic cancer cell lines. After irradiation, PK-1 and Panc-1 cells were likely to undergo necrosis, whereas MIAPaCa-2 cells underwent apoptosis. When DiO-stained immature DCs were co-incubated with DiI-stained irradiated MIAPaCa-2, it was observed under fluorescent microscopy that DCs phagocytized dead tumor cells as early as 4 h after co-incubation. The DCs' phagocytosis of irradiated tumor cells was also confirmed by flow cytometry. These results suggest that irradiated pancreatic cancer cells, which undergo both apoptosis and necrosis, could be a good source of tumor-associated antigens for cross-presentation by DCs.


Asunto(s)
Apoptosis/fisiología , Células Dendríticas/metabolismo , Necrosis , Neoplasias Pancreáticas , Fagocitosis/fisiología , Carcinoma Ductal , Línea Celular Tumoral/fisiología , Línea Celular Tumoral/efectos de la radiación , Células Dendríticas/citología , Citometría de Flujo , Humanos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/radioterapia , Fenotipo
17.
Phys Rev Lett ; 93(5): 051801, 2004 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-15323684

RESUMEN

We present a search for electron neutrino appearance from accelerator-produced muon neutrinos in the K2K long-baseline neutrino experiment. One candidate event is found in the data corresponding to an exposure of 4.8 x 10(19) protons on target. The expected background in the absence of neutrino oscillations is estimated to be 2.4+/-0.6 events and is dominated by misidentification of events from neutral current pi(0) production. We exclude the nu(micro) to nu(e) oscillations at 90% C.L. for the effective mixing angle in the 2-flavor approximation of sin((2)2theta(microe)( approximately 1/2sin((2)2theta(13))>0.15 at Deltam(2)(microe)=2.8 x 10(-3) eV(2), the best-fit value of the nu(micro) disappearance analysis in K2K. The most stringent limit of sin((2)2theta(microe)<0.09 is obtained at Deltam(2)(microe)=6 x 10(-3) eV(2).

19.
J Clin Pathol ; 57(1): 95-7, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14693847

RESUMEN

AIMS: To characterise a novel strain (M86) of adenovirus (Ad) involved in epidemic keratoconjunctivitis (EKC). METHODS/RESULTS: The virus strain was neutralised by antisera to both Ad35 and Ad11. Restriction endonuclease analysis of genomic DNA showed 98% and 88% homology with Ad11 and Ad35, respectively. The deduced amino acid sequence of the hypervariable regions of (HVRs) of the hexon gene showed a higher homology with Ad35 (94.4%) than with Ad11 (83.7%). However, it was 100% homologous to Ad35 in HVRs 1, 2, 3, and 6 and to Ad11 in HVRs 4 and 6. In the fibre knob, the isolate was more homologous to Ad11 (99.4%) than to Ad35 (29.1%). CONCLUSION: This novel strain of adenovirus showed similarities with both Ad11 and Ad35. The isolation of a novel strain like Ad35+11 is important because of its association with EKC.


Asunto(s)
Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/genética , Proteínas de la Cápside/genética , Conjuntivitis Viral/virología , Queratoconjuntivitis/virología , Adenovirus Humanos/aislamiento & purificación , Adulto , Secuencia de Aminoácidos , Genes Virales , Humanos , Masculino , Datos de Secuencia Molecular , Homología de Secuencia
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