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1.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39051856

RESUMEN

For developing and characterizing a novel compact D-T neutron spectrometer based on a single-crystal chemical vapor deposition diamond stack for plasma diagnostics toward future D-T fusion reactors, the initial measurement was performed using the accelerator-based D-T neutron sources OKTAVIAN at Osaka University. This neutron spectrometer was designed for the detection of 3-17 MeV neutrons and operated in the proton recoil telescope configuration by installing a polyethylene converter in front of the diamond stack. The measured neutron energy spectra were obtained by summing the energy of the recoil protons deposited in the diamond stack after the coincidence of the recoil protons identified by the time coincidence analysis. The neutron energy peaks measured by the compact D-T neutron spectrometer were almost in agreement with those obtained by the Monte Carlo N-Particle transport (MCNP) simulation. The energy resolution of the compact D-T neutron spectrometer was emulated to be about 4%-5% in D-T neutron measurement. In future work, the design of the compact D-T neutron spectrometer would be optimized to measure the fusion neutron for plasma diagnostics.

2.
J Hosp Infect ; 151: 140-147, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38950864

RESUMEN

BACKGROUND: While seasonality of hospital-acquired infections, including incisional SSI after orthopaedic surgery, is recognized, the seasonality of incisional SSI after general and gastroenterological surgeries remains unclear. AIM: To analyse the seasonality and risk factors of incisional SSI after general and gastroenterological surgeries. METHODS: This was a retrospective, single-institute, observational study using univariate and multivariate analyses. The evaluated variables included age, sex, surgical approach, surgical urgency, operation time, wound classification, and the American Society of Anesthesiologists physical status (ASA-PS). FINDINGS: A total of 8436 patients were enrolled. General surgeries (N = 2241) showed a pronounced SSI incidence in summer (3.9%; odds ratio (OR): 1.87; 95% confidence interval (CI): 1.05-3.27; P = 0.025) compared to other seasons (2.1%). Conversely, gastroenterological surgeries (N = 6195) showed a higher incidence in winter (8.3%; OR: 1.38; 95% CI: 1.10-1.73; P = 0.005) than in other seasons (6.1%). Summer for general surgery (OR: 1.90; 95% CI: 1.12-3.24; P = 0.018) and winter for gastroenterological surgery (1.46; 1.17-1.82; P = 0.001) emerged as independent risk factors for incisional SSI. Open surgery (OR: 2.72; 95% CI: 1.73-4.29; P < 0.001) and an ASA-PS score ≥3 (1.64; 1.08-2.50; P = 0.021) were independent risk factors for incisional SSI in patients undergoing gastroenterological surgery during winter. CONCLUSION: Seasonality exists in the incisional SSI incidence following general and gastroenterological surgeries. Recognizing these trends may help enhance preventive strategies, highlighting the elevated risk in summer for general surgery and in winter for gastroenterological surgery.

3.
Appl Radiat Isot ; 209: 111299, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38613949

RESUMEN

Glass dosimeters are very useful and convenient detection elements in radiation dosimetry. In this study, this glass dosimeter was applied to a BNCT treatment field. Boron Neutron Capture Therapy (BNCT) is a next-generation radiation therapy that can selectively kill only cancer cells. In the BNCT treatment field, both neutrons and secondary gamma-rays are generated. In other words, it is a mixed radiation field of neutrons and gamma-rays. We thus proposed a novel method to measure only gamma-ray dose in the mixed field using two RPLGD (Radiophoto-luminescence Glass Dosimeter) and two sensitivity control filters in order to control the dose response of the filtered RPLGD to be proportional to the air kerma coefficients, even if the gamma-ray energy spectrum is unknown. As the filter material iron was selected, and it was finally confirmed that reproduction of the air kerma coefficients was excellent within an error of 5.3% in the entire energy range up to 10 MeV. In order to validate this method, irradiation experiments were carried out using standard gamma-ray sources. As the result, the measured doses were in acceptably good agreement with the theoretical calculation results by PHITS. In the irradiation experiment with a volume source in a nuclear fuel storage room, the measured dose rates showed larger compared with survey meter values. In conclusion, the results of the standard sources showed the feasibility of this method, however for the volume source the dependence of the gamma-ray incident angle on the dosimeter was found to be not neglected. In the next step, it will be necessary to design a thinner filter in order to suppress the effect of the incident angle.

5.
Sci Rep ; 13(1): 22883, 2023 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-38129553

RESUMEN

Boron neutron capture therapy (BNCT) is a high-dose-intensive radiation therapy that has gained popularity due to advancements in accelerator neutron sources. To determine the dose for BNCT, it is necessary to know the difficult-to-determine boron concentration and neutron fluence. To estimate this dose, we propose a method of measuring the prompt γ-rays (PGs) from the boron neutron capture reaction (BNCR) using a Compton camera. We performed a fundamental experiment to verify basic imaging performance and the ability to discern the PGs from 511 keV annihilation γ-rays. A Si/CdTe Compton camera was used to image the BNCR and showed an energy peak of 478 keV PGs, separate from the annihilation γ-ray peak. The Compton camera could visualize the boron target with low neutron intensity and high boron concentration. This study experimentally confirms the ability of Si/CdTe Compton cameras to image BNCRs.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Compuestos de Cadmio , Puntos Cuánticos , Terapia por Captura de Neutrón de Boro/métodos , Boro/uso terapéutico , Telurio , Neutrones
6.
Appl Radiat Isot ; 199: 110897, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37352647

RESUMEN

Boron Neutron Capture Therapy (BNCT) is a cell-selective radiotherapy using a neutron capture reaction of 10B. In recent years, Accelerator Based Neutron Sources (ABNS) are under development instead of nuclear reactors for the next-generation neutron irradiation system for BNCT. However, ABNS as well as nuclear reactor usually generates unavoidable secondary gamma-rays by neutron-nuclear reactions such as capture reaction. In this research, we aimed to develop a separate measurement method of only gamma-rays in a mixed field of neutrons and gamma-rays using a fluorescent glass dosimeter (RPLGD), because most dosimeters have sensitivity to both radiation types. For this purpose, we proposed a lead filter method using two RPLGDs and lead filters. However, this method has a problem that the sensitivity to low energy gamma-rays (∼100 keV) is very small. In order to improve the sensitivity to low energy gamma-rays, we devised a method using a specially shaped lead filter. From theoretical calculations, we have shown that it was possible to estimate the air dose rate of the field where the gamma-ray energy spectrum shape was known for energies up to 10 MeV. In addition, we produced the specially shaped lead filter and experimentally confirmed the validity of the lead filter method using several gamma-ray standard sources and by measurements in a nuclear fuel storage room.

8.
J Stomatol Oral Maxillofac Surg ; 122(1): 56-61, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32302797

RESUMEN

INTRODUCTION: The assessment of facial symmetry, after mandibular reconstruction, currently relies on subjective esthetic assessment by an evaluator. The present study aimed to compare conventional subjective assessment with quantitative evaluation by three-dimensional (3D) stereophotogrammetry of facial cosmetic symmetry. METHODS: This retrospective study enrolled 20 patients who underwent mandibular reconstruction with free fibula flap after segmental resection between 2014 and 2018. Subjective assessments were performed by seven clinicians at 6-12 months after surgery. Simultaneously, lower face symmetry was measured by 3D stereophotogrammetry with the VECTRA H1 system and recorded as the root mean square deviation (RMSD). Data from the subjective and quantitative evaluations were compared using Spearman's rank correlation coefficient. RESULTS: The results showed that subjective assessments were strongly and negatively correlated with RMSD (P=0.00000128). This confirmed that RMSD, obtained by 3D stereophotogrammetry, reflected the subjective assessment of symmetry in our cohort. CONCLUSIONS: Three-dimensional stereophotogrammetry of facial cosmetic symmetry will be an available quantitative method for patients with head and neck cancer after mandibular reconstruction.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Reconstrucción Mandibular , Humanos , Fotogrametría , Estudios Retrospectivos
9.
Appl Radiat Isot ; 106: 72-4, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26275798

RESUMEN

Mock-up experiment for development of accelerator based neutron source for Osaka University BNCT project was carried out at Birmingham University, UK. In this paper, spatial distribution of neutron flux intensity was evaluated by foil activation method. Validity of the design code system was confirmed by comparing measured gold foil activities with calculations. As a result, it was found that the epi-thermal neutron beam was well collimated by our neutron moderator assembly. Also, the design accuracy was evaluated to have less than 20% error.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Oro/química , Neutrones
10.
Appl Radiat Isot ; 106: 41-4, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26297075

RESUMEN

Neutrons generated by accelerators have various energy spectra. However, only limited methods are available to measure the whole neutron energy spectrum, especially when including the epithermal region that is normally used in BNCT. In the present study, we carried out the design study on a new neutron spectrometer that can measure such a neutron spectrum more accurately, precisely and with higher energy resolution, using an unfolding technique and a liquid moderator.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Estudios de Factibilidad
11.
Blood Cancer J ; 2(5): e72, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22829974

RESUMEN

We investigated prognostic factors for the clinical outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) following imatinib-based therapy. Among 100 adult patients who were prospectively enrolled in the JALSG Ph+ALL202 study, 97 patients obtained complete remission (CR) by imatinib-combined chemotherapy, among whom 60 underwent allo-HSCT in their first CR. The probabilities of overall survival (OS) and disease-free survival (DFS) at 3 years after HSCT were 64% (95% CI, 49-76) and 58% (95% CI, 43-70), respectively. Prognostic factor analysis revealed that the major BCR-ABL transcript was the only unfavorable predictor for OS and DFS after HSCT by both univariate (HR, 3.67 (95% CI 1.49-9.08); P=0.005 and HR, 6.25 (95% CI, 1.88-20.8); P=0.003, respectively) and multivariate analyses (HR, 3.20 (95% CI, 1.21-8.50); P=0.019 and HR, 6.92 (95% CI, 2.09-22.9); P=0.002, respectively). Minimal residual disease status at the time of HSCT had a significant influence on relapse rate (P=0.015). Further study of the BCR-ABL subtype for the clinical impact on outcome of allo-HSCT in Ph+ALL is warranted.

12.
Kyobu Geka ; 61(12): 1043-7, 2008 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-19048905

RESUMEN

Aortic regurgitation (AR) and, aortic root dilatation are serious problems occurring after arterial switch operation (ASO). We have experienced a case of 12-year-old boy with aortic root dilatation and AR after ASO. Consistent progression of AR and aortic root dilatation were observed during the follow-up period. The latest Z-score of Valsalva sinus was about 9. We performed the Bentall procedure instead of aortic valve-sparing operation because of the degenerative aortic valve and the excessive aortic root dilatation. The postoperative course was uneventful. Histopathological findings of the aortic wall showed degeneration of elastic fibers on both sides of the anastmosis.


Asunto(s)
Aorta/patología , Aorta/cirugía , Insuficiencia de la Válvula Aórtica/cirugía , Procedimientos Quirúrgicos Cardiovasculares , Insuficiencia de la Válvula Aórtica/etiología , Niño , Dilatación Patológica , Cardiopatías Congénitas/cirugía , Humanos , Masculino , Complicaciones Posoperatorias
13.
Kyobu Geka ; 61(12): 1070-4, 2008 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-19048911

RESUMEN

A 92-year-old man was presented with chest pain in home clinic. And he was transferred to our hospital for emergent operation of the acute myocardial infarction. Emergent coronary angiography (CAG) revealed the occlusion of left main trunk (LMT) and 2 vessels disorder. The patent was indicated of an emergency off-pump cardiac artery bypass graft (OPCAB). Our patient had a favorable post-operative course without severe complications, and discharged on post-operative day 23. It is difficult to standarlize the cardiac operation technique and indication of advanced elderly patients. In spite of lower safety margin of nonagenarians, we have to reevaluate the indication considering with physical defect, post-operative quality of life (QOL), the will of patients and their families themselves.


Asunto(s)
Puente de Arteria Coronaria Off-Pump , Infarto del Miocardio/cirugía , Anciano de 80 o más Años , Urgencias Médicas , Humanos , Masculino
14.
Heart ; 94(8): 1002-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18308864

RESUMEN

BACKGROUND: The S100A8/A9 complex is expressed in a subset of activated neutrophils and macrophages in acute inflammatory lesions associated with various diseases. OBJECTIVE: To investigate (a) whether serum S100A8/A9 levels are increased in patients with unstable angina (UA); and (b) whether S100A8/A9 expression is upregulated in coronary atherosclerotic plaques of patients with UA. DESIGN: Serum S100A8/A9 levels in 39 patients with stable angina (SA) and 53 patients with UA were measured. In addition, the presence of the S100A8/A9 complex in directional coronary atherectomy specimens was studied immunohistochemically. Cell types which stain positive for S100A8/A9 were identified by immunodouble staining with neutrophils and macrophages. RESULTS: Mean (SD) serum S100A8/A9 levels were significantly higher in patients with UA than in those with SA (3.25 (3.08) microg/ml vs 0.77 (0.31) microg/ml, p<0.05). In patients with UA, immunodouble staining clearly showed that the S100A8/A9 complex was expressed in infiltrated neutrophils and occasional macrophages. The S100A8/A9-positive area was significantly higher in UA than in SA (mean (SD) 18.3 (14.2)% vs 1.3 (2.4)%, respectively, p<0.001). CONCLUSIONS: The S100A8/A9 complex may be involved in the inflammatory process of coronary atherosclerotic plaques in patients with UA.


Asunto(s)
Angina Inestable/metabolismo , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Enfermedad de la Arteria Coronaria/metabolismo , Neutrófilos/metabolismo , Anciano , Angina de Pecho/diagnóstico , Angina Inestable/diagnóstico , Angina Inestable/etiología , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Calgranulina A/sangre , Calgranulina B/sangre , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico , Diagnóstico Diferencial , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Infiltración Neutrófila
15.
J Food Sci ; 72(6): S412-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17995699

RESUMEN

Egg yolk decreases the absorption of iron. The effects of egg yolk protein and egg yolk phosvitin on the absorption of calcium, magnesium, and iron were investigated by in vivo studies. Male Wistar rats were fed purified diets containing casein, soy protein, or egg yolk protein for 14 d. The apparent absorptions of calcium, magnesium, and iron in the rats fed the yolk protein-based diet were lower than those in rats fed the casein- and soy protein-based diets. The apparent phosphorus absorption and the apparent protein digestibility in the yolk protein group were lower than those in the casein and soy protein groups. In the feces of the yolk protein group, serine comprised more than 30% of the amino acids. The addition of egg yolk phosvitin to the casein diets at levels of 1% and 2% (w/w) produced effects on calcium and magnesium absorptions similar to those produced by the diet containing yolk protein. The tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) pattern suggested that phosphopeptide fragments having molecular masses of 28, 22, and 15 kDa were evident in the contents of the small intestine of the rats fed phosvitin diets. These results indicate that yolk protein, when compared with casein and soy protein, decreases calcium and magnesium absorption via the resistance of phosvitin to proteolytic action.


Asunto(s)
Calcio/farmacocinética , Proteínas del Huevo/farmacología , Absorción Intestinal/efectos de los fármacos , Hierro/farmacocinética , Magnesio/farmacocinética , Fosvitina/farmacología , Animales , Calcio/antagonistas & inhibidores , Caseínas , Digestión , Relación Dosis-Respuesta a Droga , Yema de Huevo/química , Electroforesis en Gel de Poliacrilamida , Hierro/antagonistas & inhibidores , Magnesio/antagonistas & inhibidores , Masculino , Peso Molecular , Fósforo/farmacocinética , Distribución Aleatoria , Ratas , Ratas Wistar , Proteínas de Soja
17.
Eur J Cancer Care (Engl) ; 14(4): 336-41, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16098118

RESUMEN

Fourteen adult patients with haematological malignancies (eight non-Hodgkin's lymphoma, one multiple myeloma, one chronic lymphocytic leukaemia, two acute lymphoblastic leukaemia and two acute myeloid leukaemia) developed acute interstitial pneumonitis (IP) during the course of chemotherapy. All patients manifested high fever over 38 degrees C, bilateral diffuse pulmonary interstitial infiltrates in the chest radiograph and severe hypoxia without hypercapnia in the arterial blood gas analysis. Pathogenic microorganisms were not detected in repeated examinations in any patient. Chemotherapy given included various anti-neoplastic drugs. Five patients had received granulocyte colony-stimulating factor (G-CSF) for chemotherapy-induced leucopenia. The onset was associated with an increase of leucocytes in 10 patients. All patients were treated with high dose steroid hormone and broad spectrum antibiotics with or without anti-fungal agents, and three required mechanical ventilation. Eleven patients quickly recovered from these situations, whereas three died. Autopsies were done in two patients and disclosed pneumocystis carinii (PC) pneumonitis in one and non-specific pulmonary congestive oedema and fibrosis in the other. In conclusion, IP of unknown cause could develop in patients with various haematological malignancies especially at the recovery phase of chemotherapy-induced leucopenia irrespective of the previous G-CSF administration. High dose steroid hormone should be used as therapy for such patients as soon as possible after exclusion of an infective aetiology.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Hematológicas/tratamiento farmacológico , Enfermedades Pulmonares Intersticiales/etiología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Antiinfecciosos/uso terapéutico , Antiinflamatorios/uso terapéutico , Femenino , Humanos , Huésped Inmunocomprometido , Recuento de Leucocitos , Pulmón/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Masculino , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento
18.
Kyobu Geka ; 57(11): 1059-62, 2004 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-15510822

RESUMEN

We report a rare case of chronic traumatic aneurysm of the thoracic aorta. A 23-year-old man flew down from the fifth floor of his apartment for an attempted suicide. He suffered right subdural hematoma, bilateral hemothorax, lung contusions, and many other traumas. He was paralyzed by the fracture and dislocation of the first lumbar vertebra. Posterior fixation of lumbar vertebra and the segmental resection of the jejum were performed on the first and third day, respectively. He recovered well; however, he complained his nocturnal dyspnea on the forty-fifth day. Detailed examinations showed that bilateral bronchi were compressed by the aneurysm of thoracic aorta. Elective operation was performed on the sixty third day. Psudoaneurysm, 5 cm in diameter, was disclosed in the aortic isthmus. Graft replacement was undergone with the cardiopulmonary bypass. His postoperative course was uneventful, and he was transferred for the rehabilitation of his paralysis on the eigty-eighth day.


Asunto(s)
Aorta Torácica/lesiones , Aneurisma de la Aorta/cirugía , Adulto , Aneurisma de la Aorta/etiología , Humanos , Masculino , Traumatismo Múltiple , Intento de Suicidio
19.
J Chem Phys ; 121(1): 333-40, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15260552

RESUMEN

In molten equivalent salts, a unified relation that the ratio of partial dc conductivities is always equal to the inverse mass ratio, viz. sigma(+)/sigma(-)=m(-)/m(+), has been confirmed in view of microscopic point starting from the generalized Langevin equation. It has been newly proved that the memory functions assumed to be an exponentially decaying form in the Langevin equation for cation and anion are equal to each other. Furthermore, the short time behaviors of moving ions are analyzed in terms of their velocity correlation functions, according to the combination of generalized Langevin equation and damped Einstein oscillator equation. A minor correction for the expression of common friction constant derived before has been given. Estimated results for conductivities are close to those obtained by computer simulation and also comparable to experimental values.

20.
Gene Ther ; 10(26): 2119-25, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14625566

RESUMEN

Interleukin 4 (IL-4) is essential for the switching of B cells to IgE antibody production and for the maturation of T helper (Th) cells toward the Th2 phenotype. These mechanisms are thought to play a crucial role in the pathogenesis of the allergic airway inflammation observed in asthma. In the present study, we examined the anti-inflammatory effects of DNA administration of murine IL-4 mutant Q116D/Y119D (IL-4 double mutant, IL-4DM), which binds to the IL-4 receptor alpha and is an antagonist for IL-4. Immunization of BALB/c mice with alum-adsorbed ovalbumin (OVA) followed by aspiration with aerosolized OVA resulted in the development of allergic airway inflammation. A single administration of IL-4DM DNA before the aerosolized OVA challenge protected the mice from the subsequent induction of allergic airway inflammation. Serum IgE level and extent of eosinophil infiltration in bronchoalveolar lavage (BAL) from IL-4DM DNA-administered mice were significantly lower than those in BAL from control plasmid-immunized mice. In our study, IL-4 or IL-4 mutants were not detected in sera from mice that had received a single administration of IL-4DM DNA. The results of this study provide evidence for the potential utility of IL-4 mutant antagonist DNA inoculation as an approach to gene therapy for asthma.


Asunto(s)
Asma/terapia , ADN/administración & dosificación , Interleucina-4/antagonistas & inhibidores , Animales , Pruebas de Provocación Bronquial , Bronquitis/prevención & control , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Citocinas/metabolismo , Eosinófilos/metabolismo , Terapia Genética/métodos , Inmunoglobulina E/biosíntesis , Interleucina-4/administración & dosificación , Interleucina-4/genética , Ratones , Ratones Endogámicos BALB C , Mutación/genética , Ovalbúmina , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Células Th2/metabolismo , Vacunas de ADN
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