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1.
Radiologia (Engl Ed) ; 66(2): 107-113, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38614527

RESUMEN

INTRODUCTION AND OBJECTIVES: To compare gonad doses with and without a gonad protector and to optimize the use of gonadal protectors in infants thorax radiography. MATERIALS AND METHODS: Two pediatric anthropomorphic phantoms are used: an X-ray system for KXO-50SS/DRX-3724HD, and a digital radiography system for CALNEO Smart C12, with and without a gonad protector during infants thorax radiography. A real time skin dosimeter is placed on the X-ray system, and a real time skin dosimeter is inserted on the front side of the mammary gland, the front and back sides of the true pelvis level, and on the ovaries and testes. The X-ray system is irradiated 15 times using phantoms with and without a gonad protector. The measured entrance patient doses values of for the real time skin dosimeter are compared for each phantom, with and without the gonad protector. RESULTS: The medium of measured entrance patient doses values for front side dose of the true pelvis level with and without the protector are 10.00 and 5.00 µGy at newborn, and 10.00 and 0.00µGy at one year, respectively. The medium of measured entrance patient doses values for the back side dose of the true pelvis level with and without the protector are 0.00 and 0.00 µGy at both newborn one year, respectively. The measured entrance patient doses cannot be detected in the ovaries and testes with or without the protector. No significant differences are observed in the measured entrance patient doses values for the front and back side doses of the pelvis, ovaries, and testes at newborn and one year, with and without the protector (p>0.05). CONCLUSIONS: No significant difference was observed in gonad dose measurements with and without the gonad protector during infants chest radiography. We believe that gonadal protector wearing is not necessary.


Asunto(s)
Gónadas , Lactante , Recién Nacido , Humanos , Niño , Radiografía
2.
Science ; 368(6486): 67-71, 2020 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-32193363

RESUMEN

The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.

3.
Radiography (Lond) ; 25(1): 72-76, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30599834

RESUMEN

INTRODUCTION: Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined. METHODS: We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT. RESULTS: We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 µGy, whereas the maximum dose around the eye was approximately 10 µGy. CONCLUSION: By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation.


Asunto(s)
Mamografía/métodos , Fantasmas de Imagen , Dosis de Radiación , Exposición a la Radiación/estadística & datos numéricos , Sensibilidad y Especificidad
6.
Gene Ther ; 24(11): 706-716, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28820502

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a fatal disease with a median survival of 3-4 years after diagnosis. It is the most frequent form of a group of interstitial pneumonias of unknown etiology. Current available therapies prevent deterioration of lung function but no therapy has shown to improve survival. Periostin is a matricellular protein of the fasciclin 1 family. There is increased deposition of periostin in lung fibrotic tissues. Here we evaluated whether small interfering RNA or antisense oligonucleotide against periostin inhibits lung fibrosis by direct administration into the lung by intranasal route. Pulmonary fibrosis was induced with bleomycin and RNA therapeutics was administered during both acute and chronic phases of the disease. The levels of periostin and transforming growth factor-ß1 in airway fluid and lung tissue, the deposition of collagen in lung tissue and the lung fibrosis score were significantly reduced in mice treated with siRNA and antisense against periostin compared to control mice. These findings suggest that direct administration of siRNA or antisense oligonucleotides against periostin into the lungs is a promising alternative therapeutic approach for the management of pulmonary fibrosis.


Asunto(s)
Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/fisiología , Fibrosis Pulmonar/terapia , Administración Intranasal/métodos , Animales , Bleomicina/farmacología , Colágeno/análisis , Femenino , Fibroblastos/metabolismo , Fibrosis , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/terapia , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Oligonucleótidos , Oligonucleótidos Antisentido/metabolismo , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , ARN Interferente Pequeño/farmacología , Factor de Crecimiento Transformador beta/análisis
8.
Artículo en Inglés | MEDLINE | ID: mdl-28237082

RESUMEN

Arachidonic acid increased intracellular calcium, in cells expressing green fluorescent protein-tagged human FFA4 receptors, with an EC50 of ~40µM. This action was not blocked by cyclooxygenase or lipoxigenase inhibitors but it was inhibited by AH7614, a FFA4 antagonist. Arachidonic acid induced ERK activation accompanied by EGF receptor transactivation. However, EGF transactivation was not the major mechanism through which the fatty acid induced ERK phosphorylation, as evidenced by the inability of AG1478 to block it. Arachidonic acid increased FFA4 receptor phosphorylation that reached its maximum within 15min with an EC50 of ~30µM; inhibitors of protein kinase C partially diminish this effect and AH7614 blocked it. Arachidonic acid induced rapid and sustained Akt/PKB phosphorylation and FFA4 - ß-arrestin interaction. Confocal microscopy evidenced that FFA4 receptor activation and phosphorylation were associated to internalization. In conclusion, arachidonic acid is a bona fide FFA4 receptor agonist.


Asunto(s)
Ácido Araquidónico/farmacología , Receptores ErbB/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Calcio/metabolismo , Línea Celular , Células HEK293 , Humanos , Fosforilación , Quinazolinas/farmacología , Transducción de Señal/efectos de los fármacos , Tirfostinos/farmacología , beta-Arrestinas/metabolismo
9.
Rev Sci Instrum ; 87(11): 11D503, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910640

RESUMEN

The Hitomi Soft X-ray Spectrometer (SXS) was a pioneering non-dispersive imaging x-ray spectrometer with 5 eV FWHM energy resolution, consisting of an array of 36 silicon-thermistor microcalorimeters at the focus of a high-throughput soft x-ray telescope. The instrument enabled astrophysical plasma diagnostics in the 0.3-12 keV band. We introduce the SXS calibration strategy and corresponding ground calibration measurements that took place from 2012-2015, including both the characterization of the microcalorimeter array and measurements of the x-ray transmission of optical blocking filters.

10.
Phys Rev Lett ; 117(16): 162501, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27792367

RESUMEN

In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from ^{67}Kr. At the same time, no evidence for 2p emission of ^{59}Ge and ^{63}Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to ^{67}Kr as being the best new candidate among the three for two-proton radioactivity. ^{67}Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of ^{67}Kr is 7.4(30) ms.

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