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1.
Phys Rev Lett ; 128(21): 212301, 2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35687443

RESUMEN

For high-power heavy ion accelerators, the development of a suitable charge stripper, which can handle intense beams, is essential. This Letter describes the first experimental demonstration of a heavy ion liquid lithium charge stripper. A 10-20 µm thick liquid lithium jet flowing at >50 m/s was formed and confirmed stable when bombarded by various heavy ion beams, while increasing the charge state of the incoming beams to the desired charge state range. This demonstration proved the existing power limitation with the conventional strippers can be overcome by the liquid-metal stripper, opening completely new possibilities in high-power accelerator development.

2.
Phys Rev Lett ; 126(11): 114801, 2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33798347

RESUMEN

Experimental studies of the simultaneous acceleration of three-charge-state ^{129}Xe^{49+,50+,51+} beam from 17 to 180 MeV/nucleon in a superconducting linear accelerator are presented. The beam parameters for each individual- and multiple-charge-state beam were measured and compared with the particle tracking simulations. Detailed measurements were performed to characterize the multiple-charge-state beam's recombination after a second-order achromat and isopath 180° bending system. As a result of the recombination of three charge states in the six-dimensional phase space, the xenon beam intensity was increased by 2.5-fold compared to the single-charge-state beam. The results presented in the Letter fully validate the possibility to produce and utilize high-quality multiple-charge-state heavy-ion beams in a large-scale superconducting linac to increase the available beam power on an isotope production target.

4.
Phys Rev Lett ; 103(18): 182502, 2009 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-19905801

RESUMEN

We have measured the branching ratio of the three-body process in the nonmesonic weak decay of Lambda12C to be 0.29+/-0.13. This result was obtained by reproducing the nucleon and the nucleon pair yields introducing a measured final state interaction. At the same time, we have determined the absolute decay widths, Gamma(n) and Gamma(p), along with Gamma2N, whose relative ratio has been a long-standing puzzle. Including the three-body process, we have successfully reproduced the nucleon energy distribution, the coincidence two-nucleon angular correlation, and the momentum sum distribution simultaneously.

5.
Rev Sci Instrum ; 78(12): 123501, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18163726

RESUMEN

Multipoint detection is an essential requirement for investigating plasma turbulence which is a highly nonlinear phenomenon in space and time. We have fabricated an array of 64-channel poloidal probes surrounding the linear cylindrical plasma named LMD-U in order to study turbulence properties, particularly the nonlinear mode couplings, in the domain of poloidal wave number and frequency. However, misalignments of probe tips produce spurious modes, which do not exist in the real plasma, to distort the precise wave number measurements. The paper presents the description of the 64-channel poloidal probe array with means to adjust the probe positions, with discussion on the effects of the misalignments on the wave number measurements.

6.
Phys Rev Lett ; 96(6): 062301, 2006 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-16605985

RESUMEN

We performed a coincidence measurement of two nucleons emitted from the nonmesonic weak decay of lambda(5)He formed via the 6Li(pi+, K+) reaction. The energies of the two nucleons and the pair number distributions in the opening angle between them were measured. In both np and nn pairs, we observed a clean back-to-back correlation coming from the two-body weak reactions of lambda p --> np and lambda n --> nn, respectively. The ratio of the nucleon pair numbers was N(nn)/N(np) = 0.45 +/- 0.11(stat) +/- 0.03(syst) in the kinematic region of cos theta(NN) < -0.8. Since each decay mode was exclusively detected, the measured ratio should be close to the ratio of gamma(lambda p --> np)/gamma(lambda n --> nn). The ratio is consistent with recent theoretical calculations based on the heavy meson and/or direct-quark exchange picture.

7.
Australas Radiol ; 49(6): 493-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16351615

RESUMEN

We present a case in which multiple pancreatic tumours were diagnosed as metastatic clear cell renal carcinomas with chemical shift MRI (CSI) before surgery. Radiologists may be unable to recognize the loss of intensity on CSI macroscopically. We believe that it is useful to make subtraction images and calculate signal intensity on CSI, even if the lesions are multiple metastatic tumours.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Carcinoma de Células Renales/secundario , Neoplasias Renales/patología , Imagen por Resonancia Magnética/métodos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/secundario , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad
8.
Phys Rev Lett ; 94(21): 212303, 2005 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-16090313

RESUMEN

We have searched for a deeply bound kaonic state by using the FINUDA spectrometer installed at the e(+)e(-) collider DAPhiNE. Almost monochromatic K(-)'s produced through the decay of phi(1020) mesons are used to observe K(-) absorption reactions stopped on very thin nuclear targets. Taking this unique advantage, we have succeeded to detect a kaon-bound state K(-)pp through its two-body decay into a Lambda hyperon and a proton. The binding energy and the decay width are determined from the invariant-mass distribution as 115(+6)(-5)(stat)(+3)(-4)(syst) MeV and 67(+14)(-11)(stat)(+2)(-3)(syst) MeV, respectively.

9.
Phys Rev Lett ; 94(5): 052502, 2005 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-15783631

RESUMEN

In order to produce a neutron-rich Lambda hypernucleus for the first time, we carried out an experiment by utilizing the (pi-,K+) double charge-exchange reaction on a 10B target. We observed the production of a 10LambdaLi hypernucleus. The cross section for the Lambda bound region was found to be 11.3+/-1.9 nb/sr with the 1.2 GeV/c incident momentum, which is compared with the 10LambdaB hypernucleus production cross section, 7.8+/-0.3 microb/sr, in the (pi+,K+) reaction with a 1.05 GeV/c incident momentum beam.

10.
J Bone Joint Surg Br ; 86(2): 220-4, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15046437

RESUMEN

We undertook a radiographic analysis with pre-operative computed tomographic myelography in 78 patients with idiopathic scoliosis in order to analyse rotation of the spinal cord and to investigate its clinical significance. The angle of rotation of the cord had a statistically significant relationship to both that of the apical vertebra and the size of the primary curve. The relationship between the rotation of the cord and that of the apical vertebra was divided into three types. The cord rotated in the same direction as the apical vertebra in 55 patients and rotated in the opposite direction in the remaining 23 patients. In the first group, the angle of rotation of the cord was more than that of the vertebra in six patients, but less than it in 49 patients. These results suggest that the neuraxis in idiopathic scoliosis may be under tension in the axial dimension.


Asunto(s)
Escoliosis/patología , Médula Espinal/patología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Mielografía , Rotación , Escoliosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X
11.
Jpn J Clin Oncol ; 31(4): 147-52, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11386460

RESUMEN

BACKGROUND: Patients suffering from hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) generally have a poor prognosis. We therefore conducted a prospective pilot trial of combined transcatheter arterial chemoembolization (TACE) and local radiotherapy (RT) for PVTT in unresectable HCC. The aim of the study was to investigate the efficacy and toxicity of this preliminary trial regime and to explore RT guidelines for cirrhosis. METHODS: Eight patients with unresectable HCC accompanied by first branch PVTT were entered into the study from February 1998 to December 1999. TACE was performed using Lipiodol, epirubicin hydrochloride and mytomycin followed by gelatin sponge cubes. RT was started 10-14 days following TACE. A total delivered dose of 60 Gy was given as daily 2 Gy fractions, with the clinical target volume defined as PVTT only. We observed a relationship between deterioration of liver function and the percent volume of the total liver receiving a dose exceeding 30 Gy (V30). RESULTS: An objective response was observed in three of the eight patients. However, on follow-up angiograms the protrusion of PVTT into the main portal trunk was decreased in all cases. Deterioration of liver function was observed in all patients with V30 >40%. CONCLUSION: It is possible that this combined therapy prevents PVTT from spreading to the main trunk and that indicates a further benefit of TACE. Our results indicate that V30 constitutes a predictive test for the development of liver failure. More detailed evaluations of liver function and determination of the safe irradiation volume are necessary.


Asunto(s)
Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/radioterapia , Embolización Terapéutica , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/radioterapia , Células Neoplásicas Circulantes , Vena Porta , Anciano , Carcinoma Hepatocelular/patología , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Vena Porta/patología , Estudios Prospectivos
12.
Int J Radiat Oncol Biol Phys ; 50(2): 301-7, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11380215

RESUMEN

PURPOSE: Radiation pneumonitis (RP) is one of the most serious complications for patients who receive thoracic irradiation. To avoid this, early diagnosis of radiation pneumonitis is extremely important. The purpose of the present study is to investigate whether serum pulmonary surfactant proteins A and D (SP-A and SP-D, respectively) could be useful markers for RP. METHODS AND MATERIALS: Eighty-six patients (lung cancer: 42 [primary: 39, metastatic: 3], breast cancer: 23, esophageal cancer: 21) who underwent radiation therapy were prospectively studied. Radiation doses ranged from 30-76 Gy (median, 58 Gy). Serum SP-A and SP-D levels were evaluated sequentially by a sandwich enzyme-linked immunosorbent assay (ELISA) method before, during, and throughout the follow-up period until the development of symptomatic RP or until one year after completion of radiotherapy. Specificity of the ELISA results was confirmed by Western blot analysis. Patients symptomatic for RP were graded according to the Common Toxicity Criteria. RESULTS: RP occurred in 19 patients. Serum SP-D levels of patients with RP were sequentially higher than those in patients without RP. In the monitoring, serum SP-D levels at 50-60 Gy showed greater sensitivity and positive predictive values for RP detection (74% and 68%, respectively) than SP-A (26% and 21%, respectively). Western blot analysis showed that the development of RP was due to overproduction, but not proteolysis of surfactant proteins. CONCLUSION: We confirm that serum SP-A and SP-D monitoring is a practical and useful diagnostic method for the early detection of RP.


Asunto(s)
Glicoproteínas/sangre , Proteolípidos/sangre , Surfactantes Pulmonares/sangre , Neumonitis por Radiación/sangre , Neumonitis por Radiación/diagnóstico , Anciano , Anciano de 80 o más Años , Western Blotting , Femenino , Humanos , L-Lactato Deshidrogenasa/sangre , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Proteína A Asociada a Surfactante Pulmonar , Proteína D Asociada a Surfactante Pulmonar , Proteínas Asociadas a Surfactante Pulmonar , Sensibilidad y Especificidad , Neoplasias Torácicas/tratamiento farmacológico , Neoplasias Torácicas/radioterapia
13.
Ther Apher ; 5(5): 340-50, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11778918

RESUMEN

A specific system for antibody removal from blood circulation in myasthenia gravis (MG) patients was devised by use of the immunoadsorbent bound to an acetylcholine receptor (AChR) peptide that was synthesized corresponding to the sequence of residues 183-200 of the AChR alpha-subunit (alpha 183-200), antibodies which prevent the binding of ACh to AChR. The alpha 183-200 peptide was confirmed to be immunogenic for induction of an animal model of the disease and for reactivity with MG autoantibodies. We then made use of these results for immunoadsorption therapy through the antigen-antibody reaction on the molecular level, having given patients relief from myasthenic weakness. The greatest care was taken for the selection of an antigenic region in the molecular structure among various myasthenogenic domains of AChR and for the antigenic conformation of synthetic peptide as the adsorbent to react with antibodies raised against the native protein.


Asunto(s)
Técnicas de Inmunoadsorción , Ligandos , Imitación Molecular/inmunología , Miastenia Gravis/inmunología , Miastenia Gravis/terapia , Receptores Colinérgicos/inmunología , Animales , Circulación Sanguínea/fisiología , Humanos , Miastenia Gravis/sangre , Miastenia Gravis/fisiopatología , Plasmaféresis/métodos , Ratas , Ratas Endogámicas Lew
14.
Surg Today ; 30(10): 886-91, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11059727

RESUMEN

Restorative proctocolectomy with ileal pouch anal anastomosis (IPAA) has become the standard surgical procedure for ulcerative colitis (UC). The purpose of this study was to determine which factors are important to achieve good anal continence after IPAA in terms of the motor activity and pressure-volume relationship. A total of 17 patients with UC who underwent IPAA were evaluated. The internal ileal pouch pressure was transanally measured with and without volume-loading of the pouch which induces the urge to evacuate. The maximum tolerable volume (MTV), first urge volume (FUV), and ileal pouch compliance were calculated and the internal ileal pouch pressure records were subjected to spectral analysis for intensive evaluation of the intraluminal pressure waves. The FUV, correlation of the compliance of the FUV with MTV, and the remaining volume up to the MTV (RVMTV) were analyzed. Compliance of the FUV was significantly correlated with the RVMTV (r = 0.736, P < 0.01). The frequency of the phasic waves in the pouch decreased with length of follow up, reflecting improved function (r = -0.588, P < 0.05). The findings of this intensive analysis of manometric measurement indicate that the key factors in postoperative pouch function are RVMTV and the frequency of phasic waves in the W-pouch.


Asunto(s)
Canal Anal/fisiopatología , Canal Anal/cirugía , Colitis Ulcerosa/cirugía , Motilidad Gastrointestinal , Proctocolectomía Restauradora/efectos adversos , Proctocolectomía Restauradora/métodos , Adulto , Anciano , Anastomosis Quirúrgica , Colitis Ulcerosa/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Manometría , Persona de Mediana Edad , Estadísticas no Paramétricas , Factores de Tiempo
15.
Rinsho Byori ; 48(5): 385-95, 2000 May.
Artículo en Japonés | MEDLINE | ID: mdl-10892286

RESUMEN

Based on the gene-related function and molecular structure of various receptors, neurological receptor diseases were reviewed from both the immunologic and genetic perspectives. The nicotinic acetyl-choline receptor (AChR), ryanodine receptor (RyR), omega-conotoxin receptor (P/Q-type voltage-gated calcium channel), dihydropyridine receptor (L-type voltage gated calcium channel), and androgen receptor have been found to be affected by autoantibodies and/or genetic anomalies. They reflect on various neurological diseases such as myasthenia gravis, congenital myasthenic syndrome, malignant hyperthermia and central core disease, paraneoplastic myasthenic syndrome, hereditary migraine and ataxias, hypokalemic periodic paralysis, and bulbospinal muscular atrophy. The interaction of calcitonin gene-related peptide with its receptor tends to compensate the dysfunction caused by antibodies to AChR and RyR. One should look for cancers or genetic disorders in the case of the receptor disease implicated in calcium channel function. Recent advances in search for the etiology of these diseases from the standpoints of immunology and genetics have opened an avenue in understanding the functional structure of receptors and the molecular sites responsible for receptor diseases.


Asunto(s)
Enfermedades del Sistema Nervioso , Receptores Androgénicos , Receptores Colinérgicos , Canal Liberador de Calcio Receptor de Rianodina , Secuencia de Aminoácidos , Autoanticuerpos , Péptido Relacionado con Gen de Calcitonina/fisiología , Canales de Calcio/genética , Canales de Calcio Tipo L/genética , Humanos , Datos de Secuencia Molecular , Enfermedades del Sistema Nervioso/genética , Enfermedades del Sistema Nervioso/inmunología , Receptores Androgénicos/genética , Receptores de Péptido Relacionado con el Gen de Calcitonina/fisiología , Receptores Colinérgicos/genética , Canal Liberador de Calcio Receptor de Rianodina/genética
17.
Neurosci Lett ; 279(1): 57-60, 2000 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-10670787

RESUMEN

The occurrence of radiation-induced apoptosis and the determination of target cells were investigated by using the TdT-mediated dUTP-biotin nick end labeling assay and immunohistochemical analyses. The O4 immunoreactivity, an oligodendrocytes surface antigen, was also evaluated by using western blotting analysis. C57BL/6J adult female mice were subjected to single dose irradiation of 10 Gy. Eight hours after irradiation, the most significant increase of apoptotic cells was detected in the subgranular zone and the hilus of the dentate gyrus. The target cells of radiation-induced apoptosis are the subgranular progenitor cells and the oligodendrocytes in the hilus. The amount of the O4 immunoreactivity, a marker for premature oligodendrocytes, was unchanged until 8 h but enhanced after 12 h of irradiation. These results are the first to show the increase of the O4 immunoreactivity after irradiation and may be associated with the pathogenesis of radiation injury.


Asunto(s)
Antígenos de Diferenciación/efectos de la radiación , Apoptosis/efectos de la radiación , Giro Dentado/metabolismo , Giro Dentado/efectos de la radiación , Animales , Antígenos de Diferenciación/metabolismo , Apoptosis/fisiología , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Oligodendroglía/metabolismo , Oligodendroglía/efectos de la radiación , Radiación Ionizante , Células Madre/metabolismo , Células Madre/efectos de la radiación
18.
Neurosci Res ; 36(3): 183-91, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10683522

RESUMEN

Lambert-Eaton myasthenic syndrome (LEMS), often associated with small cell lung carcinoma (SCLC), is a disease of neuromuscular transmission in which antibodies directed against voltage-gated calcium channel (VGCC) in the motor nerve terminal play a crucial role in causing a deficient quantal release of acetylcholine. We focused attention on the P/Q-type VGCC, against which a majority of LEMS patients carry the specific antibody. Since the P/Q-type VGCC expresses in SCLC, the motor nerve terminal and SCLC may share a common VGCC antigen. In search for antigenic sites at the molecular level, We employed peptides or recombinant protein corresponding to the S5-S6 linker of each of four domains forming the alpha 1A subunit and tested their antigenicity. As the result, we specified the domain II, III and IV as immunodominant sites by the induction of an immune-mediated animal model of LEMS and the assay for antibodies in LEMS patients. Also, by use of peptides or recombinant protein corresponding to the synaptotagmin I, we found that in this VGCC-associated protein, the segment which exposes extracellularly during exocytosis can be antigenic for LEMS.


Asunto(s)
Enfermedades Autoinmunes/fisiopatología , Canales de Calcio Tipo Q/fisiología , Proteínas de Unión al Calcio , Síndrome Miasténico de Lambert-Eaton/fisiopatología , Animales , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Enfermedades Autoinmunes/inmunología , Canales de Calcio Tipo Q/química , Canales de Calcio Tipo Q/inmunología , Humanos , Síndrome Miasténico de Lambert-Eaton/inmunología , Glicoproteínas de Membrana/inmunología , Proteínas del Tejido Nervioso/inmunología , Sinaptotagmina I , Sinaptotagminas
19.
Mayo Clin Proc ; 75(2): 140-3, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10683651

RESUMEN

OBJECTIVE: To examine explanatory style (how people explain life events) as a risk factor for early death, using scores from the Optimism-Pessimism scale of the Minnesota Multiphasic Personality Inventory (MMPI). SUBJECTS AND METHODS: A total of 839 patients completed the MMPI between 1962 and 1965 as self-referred general medical patients. Thirty years later, the vital status of each of these patients was ascertained. RESULTS: Of the 839 patients, 124 were classified as optimistic, 518 as mixed, and 197 as pessimistic. Follow-up was available for 723 patients. Among these, a 10-point T-score increase on the Optimism-Pessimism scale (e.g., more pessimistic) was associated with a 19% increase in the risk of mortality. CONCLUSION: A pessimistic explanatory style, as measured by the Optimism-Pessimism scale of the MMPI, is significantly associated with mortality.


Asunto(s)
MMPI , Tasa de Supervivencia , Temperamento , Adulto , Anciano , Femenino , Humanos , Medicina Interna/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Valor Predictivo de las Pruebas , Riesgo , Factores de Riesgo , Tasa de Supervivencia/tendencias , Estados Unidos/epidemiología
20.
J Anesth ; 14(4): 180-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-14564562

RESUMEN

PURPOSE: This study aimed to understand the significance of unanswered and uncounted items on the illness behavior questionnaire (IBQ) in the setting of the Mayo Clinic pain management program for patients with chronic pain. METHODS: Three hundred and seventy-eight patients who completed the questionnaire were studied. The data included (1) age, (2) IQs, (3) IBQ score profiles, (4) litigation status, (5) admission status (inpatient vs outpatient), and (6) dismissal status ("graduates" vs "dropouts"). RESULTS: Comparison between patients who answered all the items (n = 272) and those who left one or more items unanswered (n = 106) showed a significant difference in the completion rate of the Wechsler Adult Intelligence Scale ( P < 0.05), Scale 5 (affective disturbance) score (P < 0.05), and the rate of dropout from the program (P < 0.05). Also, those who dropped out of the pain management program had a significantly lower score on Scale 5 (P < 0.001) and a significantly greater number of unanswered items that were not counted toward the scale score (P < 0.05). CONCLUSION: Unanswered and uncounted items of the IBQ seem to count toward a better understanding of patients' pain behavior.

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