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3.
Rev Sci Instrum ; 92(5): 053503, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243309

RESUMO

The analysis method of the Motional Stark Effect (MSE) diagnostic to measure the rotational transform and current profiles in the Large Helical Device has been improved. This was done by using the Variational Moments Equilibrium Code to calculate an equilibrium database for various pressure profiles and current profiles. This method looks for the radial profile of the rotational transform in the equilibrium database that gives the best fit to the polarization angle profiles measured with the MSE diagnostic. This analysis improves the measurements of rotational transform, especially near the magnetic axis, where the sensitivity of the polarization angle measurements becomes low and the uncertainty due to error in the estimation of the Pfirsch-Schlüter current becomes large. The radial profiles of the rotational transform and current profiles for Electron Cyclotron Current Drive and Neutral Beam Current Drive are obtained in the new analysis method with a sufficiently high accuracy to discuss the discrepancy of the current density profiles between the measurements and the calculations.

4.
Rev Sci Instrum ; 92(6): 063516, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243592

RESUMO

A new multi-tracer technique in the Tracer-Encapsulated Solid Pellet (TESPEL) method has been developed in order to acquire simultaneously the information about the behaviors of various impurities, i.e., to study concurrently the behaviors of low- and mid/high-Z impurities in magnetically confined high-temperature plasmas. In this new technique, an inorganic compound (for example, lithium titanate, Li2TiO3) is proposed to be used as a tracer embedded in the core of the TESPEL, instead of pure elements. The results of the proof-of-principle experiment clearly demonstrate the applicability of the new multi-tracer technique in the TESPEL method for the simultaneous study of behaviors of low- and mid/high-Z impurities in high-temperature plasmas.

5.
Br J Surg ; 108(2): 205-213, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33711144

RESUMO

BACKGROUND: In patients with rectal cancer, enlarged lateral lymph nodes (LLNs) result in increased lateral local recurrence (LLR) and lower cancer-specific survival (CSS) rates, which can be improved with (chemo)radiotherapy ((C)RT) and LLN dissection (LLND). This study investigated whether different LLN locations affect oncological outcomes. METHODS: Patients with low cT3-4 rectal cancer without synchronous distant metastases were included in this multicentre retrospective cohort study. All MRI was re-evaluated, with special attention to LLN involvement and response. RESULTS: More advanced cT and cN category were associated with the occurrence of enlarged obturator nodes. Multivariable analyses showed that a node in the internal iliac compartment with a short-axis (SA) size of at least 7 mm on baseline MRI and over 4 mm after (C)RT was predictive of LLR, compared with a post-(C)RT SA of 4 mm or less (hazard ratio (HR) 5.74, 95 per cent c.i. 2.98 to 11.05 vs HR 1.40, 0.19 to 10.20; P < 0.001). Obturator LLNs with a SA larger than 6 mm after (C)RT were associated with a higher 5-year distant metastasis rate and lowered CSS in patients who did not undergo LLND. The survival difference was not present after LLND. Multivariable analyses found that only cT category (HR 2.22, 1.07 to 4.64; P = 0.033) and margin involvement (HR 2.95, 1.18 to 7.37; P = 0.021) independently predicted the development of metastatic disease. CONCLUSION: Internal iliac LLN enlargement is associated with an increased LLR rate, whereas obturator nodes are associated with more advanced disease with increased distant metastasis and reduced CSS rates. LLND improves local control in persistent internal iliac nodes, and might have a role in controlling systemic spread in persistent obturator nodes.Members of the Lateral Node Study Consortium are co-authors of this study and are listed under the heading Collaborators.


Assuntos
Metástase Linfática/patologia , Neoplasias Retais/patologia , Idoso , Feminino , Humanos , Excisão de Linfonodo/mortalidade , Linfonodos/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/terapia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pelve , Neoplasias Retais/mortalidade , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Análise de Sobrevida
6.
J Endocrinol Invest ; 44(7): 1491-1500, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33206361

RESUMO

PURPOSE: Stable iodine prophylaxis helps prevent childhood thyroid cancer in nuclear emergencies; however, there is limited information on its effect on thyroid function. This study aimed to examine thyroid function and autoimmunity among children and adolescents that took stable iodine after the Fukushima Nuclear Disaster. METHODS: For this observational study, data were obtained from children and adolescents that underwent thyroid cancer screening at Hirata Central Hospital from April 2012 to March 2018. Participant characteristics, including possible hypothyroidism and hyperthyroidism, were compared between the prophylaxis and no-prophylaxis groups. Multivariable logistic regression models were used to assess for possible hypothyroidism, autoantibodies positive, and hyperthyroidism. RESULTS: A total of 1,225 participants with stable iodine prophylaxis and 3,946 without prophylaxis were enrolled. Of those participants, blood samples were available for 144 and 1,201 participants in the prophylaxis and no-prophylaxis groups, respectively. There were 17 (11.8%) and 146 cases (12.2%) of possible hypothyroidism or autoantibodies positive cases in the prophylaxis and no-prophylaxis groups, respectively, and there were no cases and 3 cases (0.2%) of possible hyperthyroidism in those two groups, respectively. Multivariable analysis for possible hypothyroidism revealed no association between stable iodine intake and possible hypothyroidism or autoantibodies positive [odds ratio 0.716 (95% confidence interval 0.399-1.284)] (p = 0.262). We did not perform multivariable analysis for hyperthyroidism due to the limited number of cases. CONCLUSION: Significant adverse effects of stable iodine intake on thyroid function were not observed among children and adolescents 7 years after the Fukushima Nuclear Disaster.


Assuntos
Acidente Nuclear de Fukushima , Iodo/administração & dosagem , Estado Nutricional , Exposição à Radiação/efeitos adversos , Doenças da Glândula Tireoide/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Doenças da Glândula Tireoide/etiologia , Adulto Jovem
7.
Comput Biol Med ; 123: 103917, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32768052

RESUMO

Intestinal parasites are responsible for several diseases in human beings. In order to eliminate the error-prone visual analysis of optical microscopy slides, we have investigated automated, fast, and low-cost systems for the diagnosis of human intestinal parasites. In this work, we present a hybrid approach that combines the opinion of two decision-making systems with complementary properties: (DS1) a simpler system based on very fast handcrafted image feature extraction and support vector machine classification and (DS2) a more complex system based on a deep neural network, Vgg-16, for image feature extraction and classification. DS1 is much faster than DS2, but it is less accurate than DS2. Fortunately, the errors of DS1 are not the same of DS2. During training, we use a validation set to learn the probabilities of misclassification by DS1 on each class based on its confidence values. When DS1 quickly classifies all images from a microscopy slide, the method selects a number of images with higher chances of misclassification for characterization and reclassification by DS2. Our hybrid system can improve the overall effectiveness without compromising efficiency, being suitable for the clinical routine - a strategy that might be suitable for other real applications. As demonstrated on large datasets, the proposed system can achieve, on average, 94.9%, 87.8%, and 92.5% of Cohen's Kappa on helminth eggs, helminth larvae, and protozoa cysts, respectively.


Assuntos
Parasitos , Animais , Humanos , Microscopia , Redes Neurais de Computação , Máquina de Vetores de Suporte
8.
Int J Clin Oncol ; 25(7): 1270-1277, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32277393

RESUMO

BACKGROUND: Nivolumab improves overall survival (OS) in patients with platinum-refractory recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). In one study, however, Kaplan-Meier OS and progression-free survival (PFS) curves for the nivolumab and cytotoxic agent arms crossed at 3-6 months, suggesting that patients with initial resistance to immunotherapy might have better outcomes with cytotoxic treatment. Here, we explored the conditions and candidates which are predictive of nivolumab outcomes in R/M HNSCC. METHODS: We retrospectively reviewed the clinical records of 27 consecutive R/M HNSCC patients treated with nivolumab from 2014 to 2018. Tumor size was evaluated by RECIST ver.1.1. Tumor growth rate (Gr) was defined as 3log(D0/Dpre)/t, where D0 and Dpre are the sum of the diameters of the target lesions (SumTLs) at baseline and pre-baseline, and t is time, with 1t defined as 4 weeks. RESULTS: Twenty-five patients were enrolled. Survival was significantly worse in patients with disease progression within 3 months. Outcomes appeared poorer in patients with higher pre-treatment Gr and bigger SumTLs at baseline. We therefore explored the association between prognosis, Gr and SumTLs. Recursive partitioning analysis showed that the characteristics of patients with disease progression after 3 months were Gr < 0.76 and SumTLs < 31.0 mm. Further, Gr < 0.76 and SumTLs < 31.0 mm was associated with significantly longer PFS (p = 0.01) and OS (p < 0.01). CONCLUSIONS: These results suggest that Gr and SumTLs at baseline are significantly associated with OS and PFS in R/M HNSCC patients treated with nivolumab.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Nivolumabe/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Idoso , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Resultado do Tratamento , Carga Tumoral
9.
Phys Rev Lett ; 123(18): 185001, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31763903

RESUMO

The isotope effect on energy confinement time and thermal transport has been investigated for plasmas confined by a stellarator-heliotron magnetic field. This is the first detailed assessment of an isotope effect in a stellarator heliotron. Hydrogen and deuterium plasmas heated by neutral beam injection on the Large Helical Device have exhibited no significant dependence on the isotope mass in thermal energy confinement time, which is not consistent with the simple gyro-Bohm model. A comparison of thermal diffusivity for dimensionally similar hydrogen and deuterium plasmas in terms of the gyroradius, collisionality, and thermal pressure has clearly shown robust confinement improvement in deuterium to compensate for the unfavorable mass dependence predicted by the gyro-Bohm model.

10.
Lupus ; 28(6): 786-789, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30917769

RESUMO

Immunoglobulin (Ig)G4-related disease (IgG4-RD) is an unusual complication of systemic lupus erythematosus (SLE). We report a case in which belimumab proved efficacious for not only SLE, but also IgG4-RD. A 58-year-old Japanese woman had suffered from photodermatosis and erythema on the limbs for 20 years. She presented in slight fever and fatigue since 2016. Laboratory data showed hypergammaglobulinemia, proteinuria and positive results for anti-nuclear antibody and anti-double-stranded DNA antibody. Furthermore, elevated levels of serum IgG4 were detected. Contrast-enhanced computed tomography disclosed multiple areas of poor enhancement in the kidneys. The patient was diagnosed with lupus nephritis and IgG4-RD from renal biopsy. Treatment was started with prednisolone at 40 mg/day and mycophenolate mofetil. Proteinuria and serological findings improved initially, but tapering the dose of glucocorticoid proved difficult. After treatment was started with belimumab, clinical symptoms and proteinuria resolved completely. The dose of glucocorticoid was successfully tapered and serum concentration of IgG4 fell further. This appears to represent the first report of a case in which both SLE and IgG4-RD were effectively treated using belimumab.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Doença Relacionada a Imunoglobulina G4/diagnóstico , Doença Relacionada a Imunoglobulina G4/tratamento farmacológico , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/tratamento farmacológico , Anticorpos Antinucleares/sangue , Feminino , Febre/etiologia , Humanos , Doença Relacionada a Imunoglobulina G4/complicações , Imunossupressores/uso terapêutico , Rim/patologia , Nefrite Lúpica/complicações , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Proteinúria/tratamento farmacológico , Proteinúria/etiologia , Tomografia Computadorizada por Raios X
12.
Clin Radiol ; 73(8): 756.e11-756.e16, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29678273

RESUMO

AIM: To determine preoperative radiological findings that may correlate with resectability and medium-term overall survival (OS) in patients with peritoneal carcinomatosis (PC) from colorectal cancer (CRC). MATERIALS AND METHODS: The study included 81 consecutive patients with PC scheduled for cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). PCI scores from preoperative computed tomography (CT) were compared with Peritoneal Cancer Index (PCI) scores at laparotomy. Odds ratio (OR), a Cox proportional hazards regression model, and Kaplan-Meier survival analyses were performed to evaluate resectability ("open and close procedure" [O&C]) and OS. RESULTS: A radiological PCI score ≥20 (OR; 20.61 p=0.001), involvement of the perihepatic region (OR; 3.63, p=0.047) and extensive small bowel involvement (OR; 9.90, p=0.019) were risk factors for O&C. Involvement of the left abdominal region correlated adversely to OS (HR; 6.86, p<0.001). CONCLUSIONS: The location of PC, in addition to the extent of PC as determined by preoperative CT, predicts resectability and medium-term survival.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/secundário , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Feminino , Fluordesoxiglucose F18 , Humanos , Hipertermia Induzida , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/cirurgia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
13.
Rev Sci Instrum ; 88(9): 093518, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28964229

RESUMO

A new Motional Stark Effect (MSE) analysis routine has been developed for improved spatial resolution in the core of the Large Helical Device (LHD). The routine was developed to reduce the dependency of the analysis on the Pfirsch-Schlüter (PS) current in the core. The technique used the change in the polarization angle as a function of flux in order to find the value of diota/dflux at each measurement location. By integrating inwards from the edge, the iota profile can be recovered from this method. This reduces the results' dependency on the PS current because the effect of the PS current on the MSE measurement is almost constant as a function of flux in the core; therefore, the uncertainty in the PS current has a minimal effect on the calculation of the iota profile. In addition, the VMEC database was remapped from flux into r/a space by interpolating in mode space in order to improve the database core resolution. These changes resulted in a much smoother iota profile, conforming more to the physics expectations of standard discharge scenarios in the core of the LHD.

14.
Eur J Radiol Open ; 4: 45-49, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28443292

RESUMO

BACKGROUND: Diffusion weighted magnetic resonance imaging (DWI) provides both functional and anatomical information regarding tumours but can also be used for tumour detection. Today, tumour treatment response in clinical trials is mainly assessed on Computed Tomography (CT) using established criteria. Despite availability of dedicated software, CT still requires significant manual work for selection and measurement in treatment response evaluation of solid tumours. PURPOSE: To compare the maximum diameter of tumour lesions on CT with the corresponding measurements on diffusion weighted images. MATERIALS AND METHODS: In this prospective cohort, metastatic lesions were identified on CT and on DWI in five patients with metastatic renal cell carcinoma before and after three months of treatment with pazopanib. Two radiologists independently measured the same lesions on axial CT images and separately also on axial DWI images. The measurements were compared between CT and DWI with respect to the number of target lesions measured, size of the lesions, size reduction due to treatment and the inter-observer variability. Wilcoxon signed rank test, linear regression and Bland-Altman plots were used for statistical analyses. RESULTS: In this pilot study, there was no significant inter-observer variability in terms of numbers of lesion selected between CT and DWI. A significant reduction of lesion size was observed both for CT and DWI when post-treatment scans were compared to pre-treatment scans. There was no significant difference in measurement of lesion size on both pre- and post treatment scans between CT and DWI (p = 0.099 and p = 0.388 respectively). CONCLUSION: Measurement of the size of metastatic lesions on the basis of axial DWI images are in close agreement with measurement based on conventional axial CT images, the most often employed approach in clinical trials today. The results in this pilot study can be used to estimate sufficient sample size in a larger trial with adequate power, were the results can be confirmed in a wider range of cancers other than renal cell carcinoma.

15.
Rev Sci Instrum ; 87(11): 11D615, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910421

RESUMO

A new tracer-encapsulated solid pellet (TESPEL) injection system has been developed additionally for the LHD heliotron. This system has three-dimensionally bended guide tubes, which allows us to inject the TESPEL obliquely on a poloidal cross-section of the LHD plasma. Consequently, this system enables us to control a tracer-impurity-deposited location more precisely. Moreover, this system can make it possible for the tracer impurity to be deposited even only inside the ergodic region (outside a last closed flux surface of the LHD plasma). A stereoscopic fast camera system has been also developed for capturing a three-dimensional TESPEL trajectory.

16.
Rev Sci Instrum ; 87(8): 083503, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27587119

RESUMO

To realize a novel vacuum-atmosphere interface that does not require a large differential pumping system, a robust cascade arc discharge source called a plasma window is constructed and tested for long-term operation. By modifying a test plasma with a direct current discharge, a vacuum interface with a high gas pressure ratio of 1/407 between the discharge and expansion sections is demonstrated for currents as high as 20 A. No significant damage to the electrodes is observed during the operation. Analysis of the visible emission spectra reveals that a stationary, stable argon plasma having a temperature of 1 eV and a density of 1.5 × 10(16) cm(-3) is generated in the plasma channel.

17.
Benef Microbes ; 7(3): 421-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27013459

RESUMO

Administration of Lactobacillus rhamnosus GG (LGG) has been reported to be therapeutically effective against acute secretory diarrhoea resulting from the structural and functional intestinal mucosal lesions induced by rotavirus infection; however, the underlying mechanisms remain to be completely elucidated. Because Toll-like receptor 3 (TLR3) plays a key role in the innate immune responses following the recognition of rotavirus, the present study examined whether LGG influences TLR3 gene expression in murine small intestine ex vivo and in vivo. We employed cultured intestinal organoids derived from small intestinal crypts as an ex vivo tissue model. LGG supplementation increased TLR3 mRNA levels in the intestinal organoids, as estimated by quantitative real-time polymerase chain reaction. Likewise, single and 7-day consecutive daily administrations of LGG increased TLR3 mRNA levels in the small intestine of C57BL/6N mice. The mRNA levels of other TLRs were not substantially altered both ex vivo and in vivo. In addition, LGG supplementation increased the mRNA levels of an antiviral type 1 interferon, interferon-α (IFN-α), and a neutrophil chemokine, CXCL1, upon stimulation with a synthetic TLR3 ligand, poly(I:C) in the intestinal organoids. LGG administration did not alter IFN-α and CXCL1 mRNA levels in the small intestine in vivo. Supplementation of other bacterial strains, Bifidobacterium bifidum and Lactobacillus paracasei, failed to increase TLR3 and poly(I:C)-stimulated CXCL1 mRNA levels ex vivo. We propose that upregulation of TLR3 gene expression may play a pivotal role in the therapeutic efficacy of LGG against rotavirus-associated diarrhoea. In addition, we demonstrated that intestinal organoids may be a promising ex vivo tissue model for investigating host-pathogen interactions and the antiviral action of probiotics in the intestinal epithelium.


Assuntos
Expressão Gênica , Intestino Delgado/patologia , Lacticaseibacillus rhamnosus/imunologia , Probióticos/administração & dosagem , Infecções por Rotavirus/patologia , Infecções por Rotavirus/prevenção & controle , Receptor 3 Toll-Like/biossíntese , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Camundongos Endogâmicos C57BL , Modelos Biológicos , Organoides , Reação em Cadeia da Polimerase em Tempo Real
18.
Anim Reprod Sci ; 164: 40-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26642748

RESUMO

The aim of this study was to assess the viability of vitrified-warmed in vivo-derived pig embryos after measuring the oxygen consumption rate. Six days after artificial insemination, blastocysts were collected from gilts and vitrified by the micro volume air cooling method. The oxygen consumption rate was measured in 60 vitrified-warmed embryos, which were then cultured for 48h to assess the viability. The survival (re-expansion) rate of embryos after warming was 85.0%. The average oxygen consumption rate of embryos immediately after warming was greater in embryos which could re-expand during subsequent culture (F=0.75±0.04) than that in those which failed to re-expand (F=0.33±0.05). Moreover, the oxygen consumption rate of vitrified-warmed embryos was greater in the hatched (F=0.88±0.06) than that in the not-hatched group (F=0.53±0.04). When the oxygen consumption rate of the vitrified-warmed embryos and the numbers of viable and dead cells in embryos were determined, there was a positive correlation between the oxygen consumption rate and the number of live cells (P<0.01, r=0.538). A total of 29 vitrified embryos after warming and measuring the oxygen consumption rate were surgically transferred into uterine horns of two recipients. Both of the recipients become pregnant and farrowed 12 healthy piglets. These results demonstrate that the oxygen consumption rate of vitrified-warmed pig embryos can be related to the number of live cells and that the measurement of oxygen consumption of embryos after cryopreservation may be useful for estimating embryo survivability.


Assuntos
Transferência Embrionária/veterinária , Consumo de Oxigênio/fisiologia , Suínos/embriologia , Coleta de Tecidos e Órgãos/veterinária , Vitrificação , Animais , Técnicas de Cultura Embrionária/veterinária , Feminino , Gravidez , Taxa de Gravidez
20.
Nat Commun ; 6: 5816, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25569268

RESUMO

The driving and damping mechanism of plasma flow is an important issue because flow shear has a significant impact on turbulence in a plasma, which determines the transport in the magnetized plasma. Here we report clear evidence of the flow damping due to stochastization of the magnetic field. Abrupt damping of the toroidal flow associated with a transition from a nested magnetic flux surface to a stochastic magnetic field is observed when the magnetic shear at the rational surface decreases to 0.5 in the large helical device. This flow damping and resulting profile flattening are much stronger than expected from the Rechester-Rosenbluth model. The toroidal flow shear shows a linear decay, while the ion temperature gradient shows an exponential decay. This observation suggests that the flow damping is due to the change in the non-diffusive term of momentum transport.

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