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1.
Radiat Prot Dosimetry ; 184(3-4): 328-333, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31038704

RESUMEN

We have recently have developed an in-situ multiple-channel depth distribution spectrometer (DDS) that can easily acquire on-site measurements of the depth distribution of specific radioactivities of Cs-134 and Cs-137 underground. Despite considerable improvements in the hardware developed for this device, the quantitative method for determining of radioactivities with this DDS device cannot yet achieve satisfactory performance for practical use. For example, this method cannot discriminate each γ-ray spectra of Cs-134 and Cs-137 acquired by the 20 thallium-doped caesium iodine CsI(Tl) scintillation crystal detectors of the DDS device from corresponding depth levels of underground soil. Therefore, we have applied deep learning neural network (DLNN) as a novel radiation measurement technique to discriminate the spectra and to determine the specific radioactivities of Cs-134 and Cs-137. We have developed model soil layers on a virtual space in Monte-Carlo based PHITS simulations and transported γ-ray radiation generated from a particular single soil layer or multiple layers as radiation sources; next, we performed PHITS calculations of those specific radioactivity measurements for each soil layer using DDS device based on machine learning via the DLNN algorithm. In this study, we obtained informative results regarding the feasibility of the proposal innovative radiation measurement method for further practical use in on-site applications.


Asunto(s)
Algoritmos , Radioisótopos de Cesio/análisis , Simulación por Computador , Conteo por Cintilación/instrumentación , Contaminantes Radiactivos del Suelo/análisis , Espectrometría gamma , Estudios de Factibilidad , Humanos , Monitoreo de Radiación
2.
Opt Express ; 27(3): 3030-3038, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732330

RESUMEN

We present a novel optical amplitude regenerator based on blue-chirp spectral slicing using a semiconductor optical amplifier (SOA). The combination of blue-chirp spectral slicing and gain competition in the SOA has a unique input/output (I/O) power-transfer function, which is controlled by the power of an input data signal injected into the SOA. The I/O power-transfer function provides selective amplitude-level regeneration of either the mark or space level of the input data signal. In this paper, we experimentally investigate the transfer function and the regeneration effect using a quantum-dot semiconductor optical amplifier. The results show that the regenerator has unique regeneration effect, specialized for either the mark or space level of a 10-Gbit/s on-off keying signal.

3.
J Biomech ; 70: 204-211, 2018 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-29336820

RESUMEN

Anchorage of pedicle screw instrumentation in the elderly spine with poor bone quality remains challenging. In this study, micro finite element (µFE) models were used to assess the specific influence of screw design and the relative contribution of local bone density to fixation mechanics. These were created from micro computer tomography (µCT) scans of vertebras implanted with two types of pedicle screws, including a full region-or-interest of 10 mm radius around each screw, as well as submodels for the pedicle and inner trabecular bone of the vertebral body. The local bone volume fraction (BV/TV) calculated from the µCT scans around different regions of the screw (pedicle, inner trabecular region of the vertebral body) were then related to the predicted stiffness in simulated pull-out tests as well as to the experimental pull-out and torsional fixation properties mechanically measured on the corresponding specimens. Results show that predicted stiffness correlated excellently with experimental pull-out strength (R2 > 0.92, p < .043), better than regional BV/TV alone (R2 = 0.79, p = .003). They also show that correlations between fixation properties and BV/TV were increased when accounting only for the pedicle zone (R2 = 0.66-0.94, p ≤  .032), but with weaker correlations for torsional loads (R2 < 0.10). Our analyses highlight the role of local density in the pedicle zone on the fixation stiffness and strength of pedicle screws when pull-out loads are involved, but that local apparent bone density alone may not be sufficient to explain resistance in torsion.


Asunto(s)
Tornillos Pediculares , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Densidad Ósea , Análisis de Elementos Finitos , Humanos , Modelos Teóricos , Estrés Mecánico , Microtomografía por Rayos X
4.
Toxicol In Vitro ; 45(Pt 1): 19-24, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28765095

RESUMEN

The bovine corneal opacity and permeability (BCOP) assay is an alternative to the Draize test in rabbits. Although it can be used to evaluate ocular non-irritants and severe irritants, it is not used for the assessment of mild-irritating substances. In this assay, a chemical with an in vitro irritancy score (IVIS)≤3 is defined as a "non-irritant" while one with an IVIS>55 is defined as a "corrosive" or "severe irritant." We attempted to evaluate mild eye irritants by assessing the recovery of corneal lesions histopathologically. Our results indicated that chemicals with IVIS≤6 may be defined as "non-irritants," because the rapid recovery of lesions limited to the squamous layer was predicted by the histopathology. In cases where lesions extended to the wing and basal cell layers, when some intact basal cells remained, the lesions were also predicted to be reversible. Thus, chemicals which induce lesions in which basal cells remain intact can be considered to be mild irritants.


Asunto(s)
Alternativas a las Pruebas en Animales/métodos , Bioensayo/métodos , Bovinos , Córnea/efectos de los fármacos , Opacidad de la Córnea/inducido químicamente , Irritantes/toxicidad , Animales , Opacidad de la Córnea/patología , Cosméticos/toxicidad , Permeabilidad
5.
Aliment Pharmacol Ther ; 44(6): 583-91, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27464849

RESUMEN

BACKGROUND: Vonoprazan, a potassium-competitive acid blocker, is expected to improve the healing of endoscopic submucosal dissection (ESD)-induced gastric ulcers compared with proton pump inhibitors (PPIs). AIM: To compare the healing status of ESD-induced gastric ulcers and the incidence of post-ESD bleeding between subjects treated with vonoprazan for 5 weeks and those treated with PPIs for 8 weeks. METHODS: Patients in the vonoprazan group (n = 75) were prospectively enrolled, whereas patients in the PPI group (n = 150) were selected for a 2:1 matched historical control cohort according to baseline characteristics including gastric ulcer size immediately following ESD, age, sex and status of Helicobacter pylori infection. Two controls per case of vonoprazan-treated group were matched with a margin of 20% in terms of ulcer size and a margin of 5 years in terms of their age. RESULTS: Although a higher number of completely healed ulcers was observed in the PPI group (95/150, 63.3%) than that in the vonoprazan group (14/75, 18.7%; P < 0.001), the ulcer size reduction rates, which were 96.0 ± 6.7% in the vonoprazan group and 94.7 ± 11.6% in the PPI group, were not significantly different (P = 0.373). The post-ESD bleeding incidence in the vonoprazan group (1/75, 1.3%) was less than that in the PPI group (15/150, 10.0%; P = 0.01). The factors affecting post-ESD bleeding incidence were the type of acid secretion inhibitor (P = 0.016) and use of an anti-thrombotic agent (P = 0.014). CONCLUSION: Vonoprazan significantly reduced post-endoscopic submucosal dissection bleeding compared with PPIs.


Asunto(s)
Resección Endoscópica de la Mucosa/efectos adversos , Hemorragia Gastrointestinal/prevención & control , Complicaciones Posoperatorias/tratamiento farmacológico , Inhibidores de la Bomba de Protones/uso terapéutico , Pirroles/uso terapéutico , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/etiología , Sulfonamidas/uso terapéutico , Adenoma/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Masculino , Persona de Mediana Edad , Rabeprazol/uso terapéutico , Neoplasias Gástricas/cirugía , Cicatrización de Heridas/efectos de los fármacos
6.
Transplant Proc ; 48(3): 929-32, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27234770

RESUMEN

BACKGROUND: Granulocyte and monocyte adsorptive apheresis (GMAA) is widely used as a treatment for active ulcerative colitis (UC) in Japan. Much attention has been paid to the possibility of GMAA for the treatment and control of cytomegalovirus (CMV) reactivation in patients with refractory UC and concomitant CMV infection. In this study, the effects of the combination of GMAA and antiviral therapy were examined in renal transplant recipients with concomitant CMV infection. METHODS: Combination therapy of GMAA and antiviral drugs was performed 9 times in 7 renal transplant recipients with concomitant CMV infection. Four of the cases were positive for CMV-IgG, and 3 were negative. The clinical presentation of CMV infection was viremia in 6 cases and disease (CMV retinitis) in 1 case. CMV infection was diagnosed by using an antigenemia assay (C7-HRP). GMAA session was performed once, and the duration of the session was 120 min. Immediately after the GMAA session, ganciclovir was administered at 5 mg/kg/body weight. CMV infection was monitored based on C7-HRP and CMV-DNA in the peripheral blood samples. RESULTS: All cases became negative for C7-HRP and CMV-DNA within 21 days (median, 14 days; range, 3-21 days) and 17 days (median, 6 days; range, 3-17 days), respectively, after starting the combination therapy. No side effects of GMAA were observed. CONCLUSIONS: This case series found that GMAA in combination with antiviral drugs may shorten the duration of treatment against CMV infection in renal transplant recipients. Further studies in a larger number of patients are required to confirm these results.


Asunto(s)
Antivirales/uso terapéutico , Eliminación de Componentes Sanguíneos , Infecciones por Citomegalovirus/terapia , Granulocitos , Trasplante de Riñón , Monocitos , Adsorción , Adulto , Anciano , Terapia Combinada , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/diagnóstico , Femenino , Ganciclovir/uso terapéutico , Humanos , Japón , Fallo Renal Crónico/cirugía , Fallo Renal Crónico/virología , Masculino , Persona de Mediana Edad
7.
Nat Commun ; 5: 3238, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24488115

RESUMEN

Johari-Goldstein or ß relaxation, persisting down to glassy state from a supercooled liquid, is a universal phenomenon of glassy dynamics. Nevertheless, the underlying micromechanisms leading to the relaxation are still in debate despite great efforts devoted to this problem for decades. Here we report experimental evidence on the structural origins of Johari-Goldstein relaxation in an ultra-quenched metallic glass. The measured activation energy of the relaxation (~26 times of the product of gas constant and glass transition temperature) is consistent with the dynamic characteristics of Johari-Goldstein relaxation. Synchrotron X-ray investigations demonstrate that the relaxation originates from short-range collective rearrangements of large solvent atoms, which can be realized by local cooperative bonding switch. Our observations provide experimental insights into the atomic mechanisms of Johari-Goldstein relaxation and will be helpful in understanding the low-temperature dynamics and properties of metallic glasses.

8.
Science ; 342(6164): 1343-5, 2013 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-24337290

RESUMEN

Noble gas molecules have not hitherto been detected in space. From spectra obtained with the Herschel Space Observatory, we report the detection of emission in the 617.5- and 1234.6-gigahertz J = 1-0 and 2-1 rotational lines of (36)ArH(+) at several positions in the Crab Nebula, a supernova remnant known to contain both molecular hydrogen and regions of enhanced ionized argon emission. Argon-36 is believed to have originated from explosive nucleosynthesis in massive stars during core-collapse supernova events. Its detection in the Crab Nebula, the product of such a supernova event, confirms this expectation. The likely excitation mechanism for the observed (36)ArH(+) emission lines is electron collisions in partially ionized regions with electron densities of a few hundred per centimeter cubed.

9.
J Dev Orig Health Dis ; 4(6): 507-12, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24924229

RESUMEN

Low birth weight was associated with cardiometabolic diseases in adult age. Insulin-like growth factor-1 (IGF-1) has a crucial role in fetal growth and also associates with cardiometabolic risks in adults. Therefore, we elucidated the association between IGF-1 level and serum lipids in cord blood of preterm infants. The subjects were 41 consecutive, healthy preterm neonates (27 male, 14 female) born at <37-week gestational age, including 10 small for gestational age (SGA) infants (<10th percentile). IGF-1 levels and serum lipids were measured in cord blood, and high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC) and very low-density lipoprotein triglyceride (VLDLTG) levels were determined by HPLC method. SGA infants had lower IGF-1 (13.1 ± 5.3 ng/ml), total cholesterol (TC) (55.0 ± 14.8), LDLC (21.6 ± 8.3) and HDLC (26.3 ± 11.3) levels, and higher VLDLTG levels (19.0 ± 12.7 mg/dl) than in appropriate for gestational age (AGA) infants (53.6 ± 25.6, 83.4 ± 18.9, 36.6 ± 11.1, 38.5 ± 11.6, 8.1 ± 7.0, respectively). In simple regression analyses, log IGF-1 correlated positively with birth weight (r = 0.721, P < 0.001), TC (r = 0.636, P < 0.001), LDLC (r = 0.453, P = 0.006), and HDLC levels (r = 0.648, P < 0.001), and negatively with log TG (r = -0.484, P = 0.002) and log VLDL-TG (r = -0.393, P = 0.018). Multiple regression analyses demonstrated that IGF-1 was an independent predictor of TC, HDLC and TG levels after the gestational age and birth weight were taken into account. In preterm SGA infants, cord blood lipids profile altered with the concomitant decrease in IGF-1 level.

11.
Pediatr Surg Int ; 28(8): 855-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22760434

RESUMEN

Early diagnosis and treatment of acute cellular rejection (ACR) after intestinal transplantation (ITx) is challenging. We report the outcome of three patients: two presented mild ACR improved with steroids. One presented steroid-resistant severe rejection, improved after rabbit anti-thymocyte globulin (r-ATG), but unfortunately died for encephalitis caused by opportunistic infections.


Asunto(s)
Suero Antilinfocítico/administración & dosificación , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Intestinos/trasplante , Adolescente , Anastomosis Quirúrgica , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Basiliximab , Niño , Daclizumab , Encefalitis/etiología , Resultado Fatal , Femenino , Humanos , Inmunoglobulina G/uso terapéutico , Enfermedades Intestinales/cirugía , Vólvulo Intestinal/cirugía , Masculino , Enfermedades del Sistema Nervioso/cirugía , Proteínas Recombinantes de Fusión/uso terapéutico , Síndrome del Intestino Corto/cirugía , Tacrolimus/administración & dosificación
12.
Transl Psychiatry ; 2: e96, 2012 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-22832861

RESUMEN

Weight gain has been identified as being responsible for increased morbidity and mortality rates of schizophrenia patients. For the management of weight gain, exercise is one of the most acknowledged interventions. At the same time, exercise and sports have been recognized for their positive impact on psychiatric symptoms of schizophrenia. However, the neurobiological basis for this remains poorly understood. We aimed to examine the effect of sports participation on weight gain, psychiatric symptoms and brain activation during sports observation in schizophrenia patients. Thirteen schizophrenia patients who participated in a 3-month program, including sports participation and 10 control schizophrenia patients were studied. In both groups, body mass index (BMI), Positive and Negative Syndrome Scale (PANSS), and brain activation during observation of sports-related actions measured by functional magnetic resonance imaging were accessed before and after a 3-month interval. BMI and general psychopathology scale of PANSS were significantly reduced in the program group but not in the control group after a 3-month interval. Compared with baseline, activation of the body-selective extrastriate body area (EBA) in the posterior temporal-occipital cortex during observation of sports-related actions was increased in the program group. In this group, increase in EBA activation was associated with improvement in the general psychopathology scale of PANSS. Sports participation had a positive effect not only on weight gain but also on psychiatric symptoms in schizophrenia. EBA might mediate these beneficial effects of sports participation. Our findings merit further investigation of neurobiological mechanisms underlying the therapeutic effect of sports for schizophrenia.


Asunto(s)
Nivel de Alerta/fisiología , Baloncesto/fisiología , Ejercicio Físico/fisiología , Lóbulo Occipital/fisiopatología , Esquizofrenia/fisiopatología , Esquizofrenia/terapia , Psicología del Esquizofrénico , Lóbulo Temporal/fisiopatología , Percepción Visual/fisiología , Adulto , Índice de Masa Corporal , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Esquizofrenia/diagnóstico , Grabación en Video , Aumento de Peso/fisiología
13.
Dis Esophagus ; 25(6): 484-90, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22098187

RESUMEN

The palisade vessels present at the distal end of the esophagus are considered to be a landmark of the esophagogastric junction and indispensable for diagnosis of columnar-lined esophagus on the basis of the Japanese criteria. Here we clarified the features of normal palisade vessels at the esophagogastric junction using magnifying endoscopy. We prospectively studied palisade vessels in 15 patients undergoing upper gastrointestinal endoscopy using a GIF-H260Z instrument (Olympus Medical Systems Co., Tokyo, Japan). All views of the palisade vessels were obtained at the maximum magnification power in the narrow band imaging mode. We divided the area in which palisade vessels were present into three sections: the area from the squamocolumnar junction (SCJ) to about 1 cm orad within the esophagus (Section 1); the area between sections 1 and 3 (Section 2); and the area from the upper limit of the palisade vessels to about 1 cm distal within the esophagus (Section 3). In each section, we analyzed the vessel density, caliber of the palisade vessels, and their branching pattern. The vessel density in Sections 1, 2, and 3 was 9.1 ± 2.1, 8.0 ± 2.6, and 3.3 ± 1.3 per high-power field (mean ± standard deviation [SD]), respectively, and the differences were significant between Sections 1 and 2 (P= 0.0086) and between Sections 2 and 3 (P < 0.0001). The palisade vessel caliber in Sections 1, 2, and 3 was 127.6 ± 52.4 µm, 149.6 ± 58.6 µm, and 199.5 ± 75.1 µm (mean ± SD), respectively, and the differences between Sections 1 and 2, and between Sections 2 and 3, were significant (P < 0.0001). With regard to branching form, the frequency of branching was highest in Section 1, and the 'normal Y' shape was observed more frequently than in Sections 2 and 3. Toward the oral side, the frequency of branching diminished, and the frequency of the 'upside down Y' shape increased. The differences in branching form were significant among the three sections (P < 0.0001). These results indicate that the density of palisade vessels is highest near the SCJ, and that towards their upper limit they gradually become more confluent and show an increase of thickness. Within a limited area near the SCJ, observations of branching form suggest that palisade vessels merge abruptly on the distal side. We have demonstrated that palisade vessels are a useful marker for endoscopic recognition of the lower esophagus.


Asunto(s)
Unión Esofagogástrica , Microvasos/anatomía & histología , Adulto , Anciano , Enfermedades del Esófago/diagnóstico , Unión Esofagogástrica/anatomía & histología , Unión Esofagogástrica/irrigación sanguínea , Esofagoscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/anatomía & histología , Membrana Mucosa/irrigación sanguínea , Imagen de Banda Estrecha/métodos , Estudios Prospectivos
15.
Curr Med Chem ; 18(22): 3402-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21728960

RESUMEN

We apply noval techniques, the Scaling Index Method (SIM), which reveals local topology of the structure, and the Minkowski Functionals (MF), which provide four global topological characteristics, to assess strength of the trabecular network of the human bone. We compare capabilities of these methods with the standard analysis, biomechanical Finite Element Method (FEM) and morphological parameters, in prediction of bone strength and fracture risk. Our study is based on a sample of 151 specimens taken from the trabecular part of human thoracic and lumbar vertebrae in vitro, visualised using µCT imaging (isotropic resolution 26µm) and tested by uniaxial compression. The sample of donors is heterogeneous, consisting of 58 male and 54 female cadavers with a mean age of 80 ±10 years. To estimate the predictive power of the methods, we correlate texture measures derived from µCT images with the maximum compressive strength (MCS) as obtained in biomechanical tests. A linear regression analysis reveals that the failure load estimated by FEM shows the highest correlation with MCS (Pearson's correlation coefficient r=0.76). None of the methods in current study is superior to the FEM: morphometric parameters give r<0.5, global topological characteristics show r=0.73 for the first Minkowski Functional MF1, which coincides with bone volume fraction BV/TV and r=0.61 for the second Minkowski functional MF2, which coincides with bone surface BS. Although scaling indices provided by SIM correlate only moderately with MCS (r=0.55), texture measures based on the nonlinear combination of local (SIM) and global (MF) topological characteristics demonstrate high correlation with experimental MCS (r=0.74) and with failure load estimated by FEM (r=0.95). Additional advantage of the proposed texture measures is possibility to reveal the role of the topologically different trabecular structure elements for the bone strength.


Asunto(s)
Fenómenos Biomecánicos , Huesos/anatomía & histología , Fuerza Compresiva , Anciano , Anciano de 80 o más Años , Huesos/fisiología , Femenino , Análisis de Elementos Finitos , Fracturas Óseas , Humanos , Vértebras Lumbares/anatomía & histología , Masculino , Métodos , Tórax/anatomía & histología , Tomografía Computarizada por Rayos X
16.
Science ; 333(6047): 1258-61, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21737700

RESUMEN

We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of about 220 times the luminosity of the Sun. The intensity and spectral energy distribution of the emission suggest a dust mass of about 0.4 to 0.7 times the mass of the Sun. The radiation must originate from the supernova ejecta and requires the efficient precipitation of all refractory material into dust. Our observations imply that supernovae can produce the large dust masses detected in young galaxies at very high redshifts.

17.
Kyobu Geka ; 64(4): 280-3, 2011 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-21491721

RESUMEN

Contralateral pneumothorax is one of severe complications after lung resection. We present our experiences with surgical treatment of 5 cases [case 4 is under the percutaneous cardiopulmonary support (PCPS) assistance] of contralateral pneumothorax after lung resection. All cases were men and not able to stop smoking, the disease caused by lung resection was lung cancer 3 and tuberculosis 2. Operative procedure was lobectomy 4 and pneumonectomy 1. Tracheal intubation was done before radiological confirmation of pneumothorax in 4 cases. Immediately after diagnosis all patients underwent chest drainage. Because the contralateral pneumothorax after lung resection is severe complication, we thought that surgical treatment is necessary. Though the thoracoscopic surgery under the PCPS assistance is also possible, it seems that a small thoracotomy with adjusting ventilation by anesthetist are more favorable. Accurate diagnosis and treatment is the key for success of treatment. The patient who receives lung resection due to lung cancer often has emphysema, and the risk of contralateral pneumothorax after the operation should also be explained.


Asunto(s)
Neumonectomía , Neumotórax/cirugía , Adulto , Anciano , Reanimación Cardiopulmonar , Humanos , Masculino , Complicaciones Posoperatorias
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