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1.
Phys Rev Lett ; 127(22): 225001, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34889640

RESUMO

We assess the magnetic field configuration in modern fusion devices by comparing experiments with the same heating power, between a stellarator and a heliotron. The key role of turbulence is evident in the optimized stellarator, while neoclassical processes largely determine the transport in the heliotron device. Gyrokinetic simulations elucidate the underlying mechanisms promoting stronger ion scale turbulence in the stellarator. Similar plasma performances in these experiments suggests that neoclassical and turbulent transport should both be optimized in next step reactor designs.

2.
BJS Open ; 3(1): 38-47, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30734014

RESUMO

Background: Recently, evaluation of quality of life (QOL) has been recognized as a significant outcome measure in the treatment of several cancers. In this study, the Anti-Cancer Drugs-Breast (ACD-B) QOL score was used to assess disease-specific survival in women with breast cancer undergoing preoperative chemotherapy (POC). Methods: QOL-ACD-B scores were evaluated before and after POC. The cut-off value of QOL-ACD-B contributing to events such as relapse or death was calculated by receiver operating characteristic (ROC) curve analysis. Results: In 300 women with breast cancer treated with POC, QOL was significantly reduced (P < 0·001). A high QOL-ACD-B score before POC was an independent factor in the multivariable analysis of overall survival (hazard ratio 0·26, 95 per cent c.i. 0·04 to 0·96). Conclusion: Evaluation by QOL-ACD-B before POC may be useful to predict the prognosis of patients with breast cancer undergoing POC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/reabilitação , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Japão , Estimativa de Kaplan-Meier , Metástase Linfática , Mastectomia , Pessoa de Meia-Idade , Terapia Neoadjuvante , Prognóstico , Psicometria , Curva ROC , Resultado do Tratamento
3.
Br J Cancer ; 113(3): 443-52, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26125445

RESUMO

BACKGROUND: The aim of this study was to clarify the role of bone marrow-derived stromal cells (BM-SCs) expressing CD271 in the development of gastric cancer. METHODS: The effect of human BM-SCs on the proliferation and motility of six gastric cancer cell lines, OCUM-2M, OCUM-2MD3, OCUM-12, KATO-III, NUGC-3, and MKN-74, was examined. CD271 expression levels in BM-SCs were analysed by flow cytometry. We also generated a gastric tumour model by orthotopic inoculation of OCUM-2MLN cells in mice that had received transplantation of bone marrow from the CAG-EGFP mice. The correlation between the clinicopathological features of 279 primary gastric carcinomas and CD271 expression in tumour stroma was examined by immunohistochemistry. RESULTS: Numerous BM-SCs infiltrated the gastric tumour microenvironment; CD271 expression was found in ∼25% of BM-SCs. Conditioned medium from BM-SCs significantly increased the proliferation of gastric cancer cell lines. Furthermore, conditioned medium from gastric cancer cells significantly increased the number of BM-SCs, whereas migration of OCUM-12 and NUGC-3 cells was significantly increased by conditioned medium from BM-SCs. CD271 expression in stromal cells was significantly associated with macroscopic type-4 cancers, diffuse-type tumours, and tumour invasion depth. The overall survival of patients (n=279) with CD271-positive stromal cells was significantly worse compared with that of patients with CD271-negative stromal cells. This is the first report of the significance of BM-SCs in gastric cancer progression. CONCLUSIONS: Bone marrow-derived stromal cells might have an important role in gastric cancer progression, and CD271-positive BM-SCs might be a useful prognostic factor for gastric cancer patients.


Assuntos
Medula Óssea/patologia , Carcinoma/patologia , Células-Tronco Mesenquimais/patologia , Neoplasias Gástricas/patologia , Animais , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos Transgênicos , Microambiente Tumoral
4.
Rev Sci Instrum ; 85(11): 113503, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430112

RESUMO

High-impedance Wire Grid (HIWG) detector has been developed to study spatiotemporal behavior of a hot electron clump generated in an electron cyclotron resonance (ECR) plasma. By measuring the floating potentials of the wire electrodes, and generating structure matrix made of geometrical means of the floating potentials, the HIWG detector reconstructs the spatial distribution of high-temperature electron clump at an arbitrary instant of time. Time slices of the spike event in floating potential revealed the growth and decay process of a hot spot occurs in an ECR plasma.


Assuntos
Elétrons , Modelos Teóricos , Gases em Plasma , Impedância Elétrica
5.
Rev Sci Instrum ; 85(9): 093510, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25273729

RESUMO

A compact and high-particle-flux thermal-lithium-beam source for two-dimensional measurement of electron density profiles has been developed. The thermal-lithium-beam oven is heated by a carbon heater. In this system, the maximum particle flux of the thermal lithium beam was ~4 × 10(19) m(-2) s(-1) when the temperature of the thermal-lithium-beam oven was 900 K. The electron density profile was evaluated in the small tokamak device HYBTOK-II. The electron density profile was reconstructed using the thermal-lithium-beam probe data and this profile was consistent with the electron density profile measured with a Langmuir electrostatic probe. We confirm that the developed thermal-lithium-beam probe can be used to measure the two-dimensional electron density profile with high time and spatial resolutions.

6.
Br J Cancer ; 109(10): 2619-28, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24129235

RESUMO

BACKGROUND: Cancer stem cells (CSCs) may be postulated mediators of the chemoresistance. This study aimed to determine an effective signal inhibitor with effects on the proliferation of CSCs in combination with anticancer drugs. METHODS: We used three gastric cancer cell lines and three side population (SP)-enriched CSC cell lines. We examined the combined effects of inhibitors against stemness signals, including c-Met inhibitor SU11274, and five anticancer drugs on the CSC proliferation and mRNA expression of chemoresistance-associated genes. RESULTS: The IC50 of irinotecan in SP-enriched CSC was 10.5 times higher than parent OCUM-2M cells, whereas that of oxaliplatin, taxol, gemcitabine, and 5-fluorouracil was 2.0, 2.8, 2.0, and 1.2, respectively. The SP cell lines had higher expression levels of UGT1A1, ABCG2, and ABCB1 than their parent cell lines. There was a synergistic antiproliferative effect with a combination of SU11274 and SN38 in SP cells, but not other inhibitors. The SU11274 significantly decreased the expression of UGT1A1, but not ABCG2 and ABCB1. The SN38 plus SU11274 group more effectively suppressed in vivo tumour growth by OCUM-2M/SP cells than either group alone. CONCLUSION: Cancer stem cells have chemoresistance to irinotecan. The c-Met inhibitor may be a promising target molecule for irinotecan-based chemotherapy of gastric cancer.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Células-Tronco Neoplásicas/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Irinotecano , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/patologia , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nucleosides Nucleotides Nucleic Acids ; 29(4-6): 314-20, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20544513

RESUMO

In order to elucidate the mechanisms of post-exercise acute renal failure, one of the complications of hereditary renal hypouricemia, we have targeted the mouse Slc22a12 gene by the exchange of exons 1-4 with pMC1neo-polyA. The knockout mice revealed no gross anomalies. The concentration ratio of urinary urate/creatinine of the knockout mice was significantly higher than that of wildtype mice, indicating an attenuated renal reabsorption of urate. The plasma levels of urate were around 11 muM and were similar among the genotypes. Although the fractional excretion of urate of knockout mice was tend to higher than that of wildtype mice, the urate reabsorption ability remained in the kidney of knockout mice, indicating a urate reabsorptive transporter other than Urat1.


Assuntos
Camundongos Knockout , Transportadores de Ânions Orgânicos/genética , Alantoína/urina , Animais , Northern Blotting , Western Blotting , Cromatografia Líquida de Alta Pressão , Creatinina/urina , Camundongos , Transportadores de Ânions Orgânicos/metabolismo , Ácido Úrico/sangue , Ácido Úrico/metabolismo , Ácido Úrico/urina
10.
Phys Rev Lett ; 100(4): 045003, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18352289

RESUMO

Three states of a magnetic island are observed when the magnetic shear at the rational surface is modified using inductive current associated with the neutral beam current drive in the Large Helical Device. One state is the healed magnetic island with a zero island width. The second state is the saturated magnetic island with partial flattening of the T(e) profile. The third state is characterized by the global flattening of the T(e) profile in the core region. As the plasma assumes each of the three states consecutively through a bifurcation process a clear hysteresis in the relation between the size of the magnetic island and the magnetic shear is observed.

11.
Kidney Int ; 71(6): 539-47, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17245393

RESUMO

The effect of acute renal failure (ARF) induced by ischemia/reperfusion (I/R) of rat kidney on the expression of organic anion transporters (OATs) was examined. The level of serum indoxyl sulfate (IS), a uremic toxin and substrate of OATs in renal tubules, shows a marked increase with the progression of ARF. However, this increase was significantly attenuated by ingestion of cobalt. The level of mRNA and protein of both rOAT1 and rOAT3 were markedly depressed in the ischemic kidney. The uptake of p-aminohippuric acid (PAH) and estrone sulfate (ES) by renal slices of ischemic rats was significantly reduced compared to control rats. Renal slices taken from ischemic rats treated with cobalt displayed significantly elevated levels of ES uptake. Cobalt intake did not affect PAH uptake, indicating the functional restoration of rOAT3 but not rOAT1. The expression of Na(+)/K(+)-ATPase was markedly depressed in the ischemic kidney, suggesting that the inward Na(+) gradient in renal tubular cells had collapsed, thereby reducing the outward gradient of alpha-ketoglutarate, a driving force of both rOATs. The decreased expression of Na(+)/K(+)-ATPase was significantly restored by cobalt treatment. Our results suggest that the downregulation of renal rOAT1 and rOAT3 could be responsible for the increase in serum IS level of ischemic rats. Cobalt treatment has a significant protective effect on ischemia-induced ARF, being accompanied by the restoration of rOAT3 and/or Na(+)/K(+)-ATPase function.


Assuntos
Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Regulação para Baixo/fisiologia , Rim/metabolismo , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Traumatismo por Reperfusão/complicações , Injúria Renal Aguda/prevenção & controle , Animais , Cobalto/uso terapêutico , Estrona/análogos & derivados , Estrona/metabolismo , Indicã/metabolismo , Rim/fisiopatologia , Masculino , Proteína 1 Transportadora de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , Oligoelementos/uso terapêutico , Ácido p-Aminoipúrico/metabolismo
12.
Oncogene ; 26(17): 2395-406, 2007 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-17130845

RESUMO

The serine protease Omi/HtrA2 was initially regarded as a proapoptotic molecule that proteolyses several proteins to induce cell death. Recent studies, however, indicate that loss of Omi protease activity increases susceptibility to stress-induced cell death. These complicated findings suggest that the protease activity of Omi is involved not only in apoptosis but also in cellular homeostasis. However, the targets which Omi uses to mediate this novel process are unknown. Previously, we showed that WARTS (WTS)/large tumor-suppressor 1 mitotic kinase interacts with the protein/discs-large protein/zonula (PDZ) domain of Omi and promotes its protease activity. We now report that WTS is a substrate for Omi protease activity, thus it is not only a regulator but also a downstream target of this protease. Interaction with Omi PDZ domain is required for WTS to be proteolysed. When caspase-9-deficient mouse embryonic fibroblasts (MEFs) were treated with staurosporine, WTS was proteolysed by activated endogenous Omi without induction of cell death. Therefore, protease activity of Omi and proteolysis of WTS are not necessarily required for cell death. We found that depletion of Omi from HeLa cells results in accelerated cell proliferation despite no significant change in the duration of mitosis. The depletion of WTS showed the same effect on S phase progression. Therefore, WTS proteolytic fragment(s) generated by Omi may act as an inhibitor of G1/S progression. Our data reveal a role for Omi-mediated processing of WTS in negative regulation of cell cycle progression at interphase, suggesting a novel function of Omi other than apoptosis.


Assuntos
Proliferação de Células , Proteínas Mitocondriais/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Serina Endopeptidases/fisiologia , Animais , Apoptose/fisiologia , Células COS , Chlorocebus aethiops , Células HeLa , Serina Peptidase 2 de Requerimento de Alta Temperatura A , Humanos , Interfase/fisiologia , Especificidade por Substrato
13.
Phys Rev Lett ; 97(5): 055002, 2006 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-17026108

RESUMO

In reduced recycling discharges in the Large Helical Device, a super dense core plasma develops when a series of pellets are injected. A core region with density as high as 4.5 x 10(20) m(-3) and temperature of 0.85 keV is maintained by an internal diffusion barrier with very high-density gradient. These results may extrapolate to a scenario for fusion ignition at very high density and relatively low temperature in helical devices.

14.
Gene ; 341: 41-7, 2004 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-15474286

RESUMO

Using a gene trap technique, we identified a murine homologue of the yeast LUC7-like gene (Luc7l), which is a serine-arginine-rich protein (SR protein) that localizes in the nucleus through its arginine-serine-rich domain (RS domain) at the C-terminus and shows a speckled distribution pattern. Although its transcripts are widely expressed in embryos and adults, they are rarely detected in adult skeletal muscle, and Luc7l expression was found to be negatively regulated during the course of development of limb skeletal muscle, as well as during in vitro differentiation of the myoblast cell lines Sol8 and C2C12. We also demonstrated that forced expression of Luc7l protein inhibited myogenesis in vitro. Based on our results, Luc7l is thought to play an important role in the regulation of muscle differentiation.


Assuntos
Desenvolvimento Muscular/genética , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/genética , Animais , Northern Blotting , Western Blotting , Células COS , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular , Chlorocebus aethiops , Regulação para Baixo/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Masculino , Camundongos , Camundongos Mutantes , Microscopia de Fluorescência , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/embriologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Mioblastos/citologia , Mioblastos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
15.
Eur Surg Res ; 36(5): 323-30, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15359097

RESUMO

BACKGROUND: Peritoneal defects lead to serious postoperative problems. Thus the development of physiological material to cover peritoneal defects is very desirable. AIM: The aim of this study was to develop a transplantable artificial peritoneum. METHOD: The artificial peritoneum consisted of collagen gel, fibroblasts, and mesothelial cells, and histological features were analyzed. The artificial peritoneum at the site of a peritoneal defect in the rat was transplanted to the abdominal wall. RESULTS: Histological examination revealed that the artificial peritoneum consisted of a flat mesothelial monolayer upon a stromal matrix. All transplanted artificial peritoneums adapted well to the host and prevented severe adhesion. CONCLUSION: Our artificial peritoneum may be a useful transplantable bioengineered material for repair of surgical peritoneal defects.


Assuntos
Órgãos Artificiais , Peritônio , Engenharia Tecidual , Parede Abdominal/cirurgia , Animais , Adesão Celular , Células Epiteliais/metabolismo , Humanos , Imuno-Histoquímica/métodos , Masculino , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Peritônio/cirurgia , Ratos , Ratos Endogâmicos , Coloração e Rotulagem , Aderências Teciduais/prevenção & controle
17.
Phys Rev Lett ; 92(5): 055002, 2004 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-14995316

RESUMO

Evidence for a reduction of heat transport inside the magnetic island O point is observed from the propagation of a cold pulse produced by a tracer encapsulated solid pellet in the Large Helical Device. A small peak and slow propagation of the cold pulse are observed inside the island. A significant result is that electron heat diffusivity inside the island is estimated to be 0.2 m(2)/s which is smaller than that outside the island by an order of magnitude.

18.
Phys Rev Lett ; 91(24): 245001, 2003 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-14683130

RESUMO

The helicity-induced Alfvén eigenmodes (HAEs) with the toroidal mode number n=2 and 3 are observed for the first time in the Large Helical Device plasmas heated by neutral beam injection. The observed mode frequency is about 8 times higher than that of the observed toroidicity-induced Alfvén eigenmodes, and is proportional to the Alfvén velocity. The modes are excited when the ratio of the beam velocity to the Alfvén velocity exceeds about unity. The frequency lies just above the lower bound of the HAE gap in the plasma edge region of rho>0.7 (rho: normalized minor radius).

19.
J Clin Pharm Ther ; 28(4): 319-27, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12911685

RESUMO

BACKGROUND: Although it is well known that drug-drug interactions may lead to toxicity and therapeutic failure, little is known about the incidence and consequences of herb-drug interactions in patients receiving Kampo medicines. METHODS: We evaluated the frequency of the combined use of Kampo medicines and Western drugs at Osaka University Hospital, and investigated the effects of these formulae on the metabolic activity of different cytochrome P450 (CYP) isoforms using pooled microsomes obtained from human liver. RESULTS: Twenty-two Kampo formulae were used together with 40 Western drugs catalyzed by the CYP isoforms CYP3A4, CYP2C9, CYP2D6 and CYP1A2. Among the Kampo medicines, HOCHUEKKI-TO, SHOSAIKO-TO, NINJINYOUEI-TO, SAIREI-TO and KAKKON-TO were most frequently used during the study period (1996-2000). These were co-administered with 11 categories of drugs, which are substrates for CYP3A4. HOCHUEKKI-TO and SAIREI-TO were competitive inhibitors of CYP3A4 with Ki values of 0.65 and 0.1 mg/mL, respectively. HOCHUEKKI-TO, SHOSAIKO-TO and SAIREI-TO inhibited the metabolic activities of CYP2C9, but had no effect on CYP2D6. HOCHUEKKI-TO and SAIREI-TO exhibited non-competitive inhibition of the metabolic activity of CYP2C9 with a similar Ki value (0.7-0.8 mg/mL). SAIRE-TO (0.25 mg/mL) was a potent inhibitor of CYP1A2 (inhibition > 68%). CONCLUSIONS: Frequently used Kampo medicines may interact with Western drugs, which are substrates for CYP3A4, CYP2C9 and CYP1A2. Their co-administration should be undertaken with care.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Interações Ervas-Drogas , Medicina Kampo , Microssomos Hepáticos/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Técnicas In Vitro , Isoenzimas/metabolismo , Microssomos Hepáticos/enzimologia
20.
Phys Rev Lett ; 90(20): 205001, 2003 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-12785901

RESUMO

Sawtooth oscillations have been observed in current-carrying helical plasmas by using electron-cyclotron-emission diagnostics in the Large Helical Device. The plasma current, which is driven by neutral beam injection, reduces the beta threshold of the sawtooth oscillation. When the central q value is increased due to the plasma current, the core region crashes, and, when it is decreased, the edge region crashes annularly. Observed rapid mixture of the plasma in the limited region suggests that these sawtooth crashes are reconnection phenomena. Unlike previous experiments, no precursor oscillation has been observed.

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