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1.
Cancers (Basel) ; 13(23)2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34885155

ABSTRACT

Track-structure Monte Carlo simulations are useful tools to evaluate initial DNA damage induced by irradiation. In the previous study, we have developed a Gean4-DNA-based application to estimate the cell surviving fraction of V79 cells after irradiation, bridging the gap between the initial DNA damage and the DNA rejoining kinetics by means of the two-lesion kinetics (TLK) model. However, since the DNA repair performance depends on cell line, the same model parameters cannot be used for different cell lines. Thus, we extended the Geant4-DNA application with a TLK model for the evaluation of DNA damage repair performance in HSGc-C5 carcinoma cells which are typically used for evaluating proton/carbon radiation treatment effects. For this evaluation, we also performed experimental measurements for cell surviving fractions and DNA rejoining kinetics of the HSGc-C5 cells irradiated by 70 MeV protons at the cyclotron facility at the National Institutes for Quantum and Radiological Science and Technology (QST). Concerning fast- and slow-DNA rejoining, the TLK model parameters were adequately optimized with the simulated initial DNA damage. The optimized DNA rejoining speeds were reasonably agreed with the experimental DNA rejoining speeds. Using the optimized TLK model, the Geant4-DNA simulation is now able to predict cell survival and DNA-rejoining kinetics for HSGc-C5 cells.

2.
Free Radic Res ; 55(5): 547-555, 2021 May.
Article in English | MEDLINE | ID: mdl-34569399

ABSTRACT

The effects of a magnetic field longitudinal to the ion beam track on the generation of hydroxyl radicals (•OH) and hydrogen peroxide (H2O2) in water were investigated. A longitudinal magnetic field was reported to enhance the biological effects of the ion beam. However, the mechanism of the increased cell death by a longitudinal magnetic field has not been clarified. The local density of •OH generation was estimated by a method based on the EPR spin-trapping. A series of reaction mixtures containing varying concentrations (0.76‒2278 mM) of DMPO was irradiated by 16 Gy of carbon- or iron-ion beams at the Heavy-Ion Medical Accelerator in Chiba (HIMAC, NIRS/QST, Chiba, Japan) with or without a longitudinal magnetic field (0.0, 0.3, or 0.6 T). The DMPO-OH yield in the sample solutions was measured by X-band EPR and plotted versus DMPO density. O2-dependent and O2-independent H2O2 yields were measured. An aliquot of ultra-pure water was irradiated by carbon-ion beams with or without a longitudinal magnetic field. Irradiation experiments were performed under air or hypoxic conditions. H2O2 generation in irradiated water samples was quantified by an EPR spin-trapping, which measures •OH synthesized from H2O2 by UVB irradiation. Relatively sparse •OH generation caused by particle beams in water were not affected by loading a magnetic field on the beam track. O2-dependent H2O2 generation decreased and oxygen-independent H2O2 generation increased after loading a magnetic field parallel to the beam track. Loading a magnetic field to the beam track made •OH generation denser or made dense •OH more reactive.


Subject(s)
Hydrogen Peroxide , Water , Cyclic N-Oxides , Electron Spin Resonance Spectroscopy , Hydroxyl Radical , Magnetic Fields , Reactive Oxygen Species
3.
Phys Med Biol ; 66(5)2021 02 12.
Article in English | MEDLINE | ID: mdl-33477116

ABSTRACT

A development project for hypo-fractionated multi-ion therapy has been initiated at the National Institute of Radiological Sciences in Japan. In the treatment, helium, carbon, oxygen, and neon ions will be used as primary beams with pencil beam scanning. A ripple filter (RiFi), consisting of a thin plastic or aluminum plate with a fine periodic ridge and groove structure, has been used to broaden the Bragg peak of heavy-ion beams in the beam direction. To sufficiently broaden the Bragg peak of helium-, carbon-, oxygen-, and neon-ion beams with suppressed lateral scattering and surface dose inhomogeneity, in this study, we tested a plate made of a lung substitute material, Gammex LN300, as the RiFi. The planar integrated dose distribution of a 183.5 MeV u-1neon-ion beam was measured behind a 3 cm thick LN300 plate in water. The Bragg peak of the pristine beam was broadened following the normal distribution with the standard deviationσvalue of 1.29 mm, while the range of the beam was reduced by 8.8 mm by the plate. To verify the LN300 performance as the RiFi in multi-ion therapy, we measured the pencil beam data of helium-, carbon-, oxygen- and neon-ion beams penetrating the 3 cm thick LN300 plate. The data were then modeled and used in a treatment planning system to achieve a uniform 10% survival of human undifferentiated carcinoma cells within a cuboid target by the beam for each of the different ion species. The measured survival fractions were reasonably reproduced by the planned ones for all the ion species. No surface dose inhomogeneity was observed for any ion species even when the plate was placed close to the phantom surface. The plate made of lung substitute material, Gammex LN300, is applicable as the RiFi in multi-ion therapy with helium-, carbon-, oxygen- and neon-ion beams.


Subject(s)
Heavy Ion Radiotherapy , Helium , Carbon/therapeutic use , Helium/therapeutic use , Humans , Lung , Neon/therapeutic use , Oxygen/therapeutic use , Radiotherapy Planning, Computer-Assisted , Water/chemistry
4.
Head Neck ; 43(2): 514-519, 2021 02.
Article in English | MEDLINE | ID: mdl-33015926

ABSTRACT

BACKGROUND: We analyzed the effects of early nutritional intervention by a nutritional support team (NST) in patients with head and neck squamous cell carcinoma (HNSCC) undergoing chemoradiotherapy or radiotherapy. METHODS: This study investigated whether early nutritional interventions by a multidisciplinary NST improve body weight loss, mucositis, serum albumin level, and hospital length of stay. RESULTS: Sixty-one patients with HNSCC were treated during the study, and 32 patients received NST intervention since admission. The median weight loss rates were 3.3% and 7.3% and grade 3 mucositis was observed in 25.0% and 70.0% of patients in the intervention and nonintervention groups, respectively. In the intervention group, serum albumin level through treatment increased and the hospital length of stay from the end of treatment was shortened. CONCLUSION: Early nutritional intervention by a multidisciplinary NST improved body weight loss rate, mucositis, albumin level, and hospital length of stay, which might lead to better clinical outcomes.


Subject(s)
Head and Neck Neoplasms , Mucositis , Chemoradiotherapy/adverse effects , Head and Neck Neoplasms/therapy , Humans , Nutritional Support , Squamous Cell Carcinoma of Head and Neck/therapy
5.
Gan To Kagaku Ryoho ; 44(1): 63-65, 2017 Jan.
Article in Japanese | MEDLINE | ID: mdl-28174382

ABSTRACT

A 62-year-old male was diagnosed with large cell lung cancer(c-Stage IV)based on pathological examination of an anterior chest tumor. He received chemotherapy with cisplatin, pemetrexed, and bevacizumab. He suffered from persistent hiccups from day 2 of the first course of chemotherapy. He was unsuccessfully treated with chlorpromazine, shakuyakukanzoto, and gabapentin. Therefore, we administered pregabalin to him, and his hiccups subsided immediately. To prevent hiccups, he subsequently took pregabalin along with his chemotherapy regimen, and was able to receive 4 courses of chemotherapy without persistent hiccups. Pregabalin is a possible therapeutic option for treating persistent chemotherapy-induced hiccups.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/adverse effects , Hiccup/drug therapy , Lung Neoplasms/drug therapy , Oxonic Acid/adverse effects , Pregabalin/therapeutic use , Tegafur/adverse effects , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/pathology , Adenocarcinoma of Lung , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cisplatin/administration & dosage , Drug Combinations , Hiccup/chemically induced , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Male , Middle Aged , Oxonic Acid/administration & dosage , Tegafur/administration & dosage , Treatment Outcome
6.
Am J Hosp Palliat Care ; 33(4): 340-5, 2016 May.
Article in English | MEDLINE | ID: mdl-25433067

ABSTRACT

PURPOSE: To evaluate the effectiveness of specialized palliative care (PC) administered at the time of administration of first-line chemotherapy for cancer progression. METHODS: Patients who received regular specialist PC concomitantly with first-line chemotherapy after being diagnosed with progressive disease assigned to PC group. Patients transferred to palliative care unit (PCU) after discontinuation of chemotherapy were assigned to standard care (SC) group. We evaluated quality of palliative care using Support Team Assessment Schedule, quality of life (QOL) using Good Death Inventory, and short-term mortality in PCU. RESULTS: A total of 28 and 63 patients patients were assigned to PC and SC groups, respectively. Physical symptoms, anxiety, communication scores, and QOL scores were significantly higher in the PC group (P < .001). Short-term mortality (<14 days) was significantly higher in the SC group (P = .0005). CONCLUSION: This approach may facilitate high quality of PC.


Subject(s)
Antineoplastic Agents/administration & dosage , Neoplasms/drug therapy , Palliative Care/organization & administration , Quality of Health Care/organization & administration , Terminal Care/organization & administration , Aged , Antineoplastic Agents/therapeutic use , Attitude to Death , Communication , Female , Humans , Male , Mental Health , Middle Aged , Neoplasms/mortality , Neoplasms/psychology , Palliative Care/standards , Patient Care Team/organization & administration , Patient Comfort/organization & administration , Quality of Health Care/standards , Quality of Life , Terminal Care/standards , Time Factors
7.
PLoS One ; 10(8): e0129349, 2015.
Article in English | MEDLINE | ID: mdl-26247356

ABSTRACT

PURPOSE: Nurses and other healthcare workers frequently experience belief conflict, one of the most important, new stress-related problems in both academic and clinical fields. METHODS: In this study, using a sample of 1,683 nursing practitioners, we developed The Assessment of Belief Conflict in Relationship-14 (ABCR-14), a new scale that assesses belief conflict in the healthcare field. Standard psychometric procedures were used to develop and test the scale, including a qualitative framework concept and item-pool development, item reduction, and scale development. We analyzed the psychometric properties of ABCR-14 according to entropy, polyserial correlation coefficient, exploratory factor analysis, confirmatory factor analysis, average variance extracted, Cronbach's alpha, Pearson product-moment correlation coefficient, and multidimensional item response theory (MIRT). RESULTS: The results of the analysis supported a three-factor model consisting of 14 items. The validity and reliability of ABCR-14 was suggested by evidence from high construct validity, structural validity, hypothesis testing, internal consistency reliability, and concurrent validity. The result of the MIRT offered strong support for good item response of item slope parameters and difficulty parameters. However, the ABCR-14 Likert scale might need to be explored from the MIRT point of view. Yet, as mentioned above, there is sufficient evidence to support that ABCR-14 has high validity and reliability. CONCLUSION: The ABCR-14 demonstrates good psychometric properties for nursing belief conflict. Further studies are recommended to confirm its application in clinical practice.


Subject(s)
Burnout, Professional/psychology , Nurses/psychology , Psychometrics/methods , Adult , Conflict, Psychological , Factor Analysis, Statistical , Female , Humans , Interprofessional Relations , Male , Middle Aged , Nurse-Patient Relations , Surveys and Questionnaires
8.
Gan To Kagaku Ryoho ; 42 Suppl 1: 69-71, 2015 Dec.
Article in Japanese | MEDLINE | ID: mdl-26809417

ABSTRACT

The objective of this study is to understand the issues and solutions considered by certified nurses(CN)in palliative care (hereinafter referred to as"palliative care CN)regarding discharge support and regional cooperation for cancer patients, and to discover the roles and responsibilities of palliative care CN. Data obtained from training sessions for 22 palliative care CNs was reconfigured and analyzed. As a result, problems related to discharge support and regional cooperation for cancer patients were classified into 13 categories and 3 core categories. The following roles for palliative care CN were proposed to promote discharge support and regional cooperation for cancer patients: (1) Inter-professional sharing of knowledge about patients and their families to reconcile the intentions of the patient and family members with predictions of progression of the illness; (2) Enable hospital nurses to obtain information about patients after discharge in order to establish a clear image for medical treatment; and(3) Support for ward nurses regarding cooperation to alleviate symptoms and offer medical care to patients who are highly dependent on medical care, and to become a point of contact for cooperation with visiting nurses.


Subject(s)
Neoplasms/therapy , Nurse's Role , Palliative Care , Patient Care Team , Patient Discharge , Humans
9.
Am J Hosp Palliat Care ; 31(7): 699-709, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24113194

ABSTRACT

To clarify physicians' practices and attitudes regarding advance care planning (ACP) in palliative care units (PCUs) in Japan, we conducted a self-completed questionnaire survey of 203 certificated PCUs in 2010. Ninety-nine physicians participated in the survey. Although most Japanese palliative care physicians recognized the importance of ACP, many failed to implement aspects of patient-directed ACP that they acknowledged to be important, such as recommending completion of advance directives (ADs), designation of health care proxies, and implementing existing ADs. The physicians' general preference for family-centered decision making and their feelings of difficulty and low confidence regarding ACP most likely underlie these results. The discrepancy between physicians' practices and their recognition of the importance of ACP suggests an opportunity to improve end-of-life care.


Subject(s)
Advance Care Planning , Advance Directives/psychology , Advance Directives/statistics & numerical data , Hospice Care/psychology , Palliative Care/psychology , Physicians/psychology , Terminal Care/psychology , Adult , Aged , Aged, 80 and over , Attitude of Health Personnel , Decision Making , Female , Health Knowledge, Attitudes, Practice , Humans , Japan , Male , Middle Aged , Physician-Patient Relations , Surveys and Questionnaires , Young Adult
10.
Chemistry ; 16(3): 890-8, 2010 Jan 18.
Article in English | MEDLINE | ID: mdl-19937617

ABSTRACT

We synthesized a series of 1,4,7,10-tetraalkyltetracenes using a new 2,6-naphthodiyne precursor and 2,5-dialkylfurans as starting materials (alkyl=methyl to hexyl). Surprisingly, the solid-state color of the tetracenes ranges through yellow, orange, and red. Both yellow and red solids are obtained for the butyl derivative. Optical properties in solution show no marked differences; however, those in the solid state show characteristics that vary with alkyl side-chain length: methyl, propyl, and pentyl derivatives are orange; ethyl and butyl derivatives are yellow; and another butyl and hexyl derivative are red. X-ray analyses reveal that the molecular structures are planar, semi-chair, or chair forms; the chair form takes a herringbone-like arrangement and the other forms take slipped parallel arrangements. The mechanism of crystallochromy is discussed in terms of molecular structure, crystal packing, and calculations that take account of exciton coupling.

11.
Disabil Rehabil ; 30(7): 559-64, 2008.
Article in English | MEDLINE | ID: mdl-17852319

ABSTRACT

PURPOSE: To elucidate the current status of cancer rehabilitation in institutions nationwide. METHOD: A questionnaire survey regarding the current status of cancer rehabilitation in 1693 healthcare institutions was conducted by mail. The survey first asked whether rehabilitation was being conducted for cancer patients and, in facilities in which it was being conducted, it then asked about the content of the rehabilitation, the stage of the cancer patients, etc. Facilities in which cancer rehabilitation was not being conducted were surveyed in regard to whether there was a need for cancer rehabilitation. RESULTS: Valid replies were obtained from 1045 (62.0%) institutions and 864 (82.7%) of them conducted rehabilitation for cancer patients. A high proportion of the content of the rehabilitation was found to be related to physical function. Activities of daily living guidance and training were also found to be conducted in a high proportion. Low proportions of the facilities conducted content that was specialized for cancer. Of the 181 facilities in which rehabilitation was not being conducted for cancer patients, 171 (94.5%) replied that they felt that rehabilitation was needed for cancer patients. CONCLUSIONS: Based on the results of this fact-finding survey it will be necessary to consider strategies for popularizing and developing rehabilitation programmes for cancer patients in Japan.


Subject(s)
Neoplasms/rehabilitation , Rehabilitation Centers/trends , Activities of Daily Living , Data Collection , Humans , Japan , Occupational Therapy/statistics & numerical data , Physical Therapy Modalities/statistics & numerical data
12.
Phys Rev Lett ; 96(1): 017008, 2006 Jan 13.
Article in English | MEDLINE | ID: mdl-16486505

ABSTRACT

We report systematic, high-precision measurements of the low-T (down to 70 mK) thermal conductivity kappa of YBa2Cu3O(y), La(2-x)Sr(x)CuO4, and Bi2Sr2CaCu2O(8+delta). Careful examinations of the Zn- and hole-doping dependences of the residual thermal conductivity kappa0/T, as well as the in-plane anisotropy of kappa0/T in Bi2Sr2CaCu2O(8+delta), indicate a breakdown of the universal thermal conductivity, a notable theoretical prediction for d-wave superconductors. Our results point to an important role of electronic inhomogeneities, which are not considered in the standard perturbation theory for thermal conductivity, in the underdoped to optimally doped regime.

13.
Phys Rev Lett ; 95(11): 117005, 2005 Sep 09.
Article in English | MEDLINE | ID: mdl-16197037

ABSTRACT

We report time-resolved measurements of the photoinduced change in reflectivity, DeltaR, in the Bi2Sr2Ca(1-y)Dy(y)Cu2O8+delta (BSCCO) system of cuprate superconductors as a function of hole concentration. We find that the kinetics of quasiparticle decay and the sign of DeltaR both change abruptly where the superconducting transition temperature T(c) is maximal. These coincident changes suggest that a sharp transition in quasiparticle dynamics takes place precisely at optimal doping in the BSCCO system.

14.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 61(12): 1609-15, 2005 Dec 20.
Article in English | MEDLINE | ID: mdl-16395235

ABSTRACT

To reduce errors in the carbon beam distribution between the treatment planning system and the actual situation, we evaluated the geometrical accuracy, volume accuracy, water-equivalent length (WEL), and treatment planning, and compared the results of evaluation of axial and helical scan methods with various scan parameters. The results indicated that both scan methods showed good geometrical accuracy for thin slice images, but for thick slice images it is easier to understand the phantom as a sphere from the helical as compared with the axial scan. Treatment planning with a thin slice thickness (ST) provided accurate dose distribution for both scan methods, and the dose distribution on the treatment planning system was almost the same as that in the actual situation. Not all institutes, however, can obtain thin slice CT images, and some have used thick slice CT images in planning. For the axial scan, such thick slice images induced differences in dose distribution between treatment planning and the actual situation. Helical scans with a small, reconstructed increment reduced these differences even with relatively thick CT images. To achieve a more accurate dose distribution, radiation therapy planning should be performed using a thin ST for both scan methods or the helical scan with a small, reconstructed increment. Although we reached this conclusion using a carbon beam, it also may be applicable to proton beam therapy.


Subject(s)
Radiotherapy Planning, Computer-Assisted , Tomography Scanners, X-Ray Computed , Tomography, X-Ray Computed/instrumentation , Tomography, X-Ray Computed/methods , Carbon , Phantoms, Imaging , Radiation Dosage , Radiotherapy Planning, Computer-Assisted/standards , Tomography, Spiral Computed
15.
Phys Rev Lett ; 88(14): 147003, 2002 Apr 08.
Article in English | MEDLINE | ID: mdl-11955170

ABSTRACT

Using infrared spectroscopy, we found that changes in the in-plane charge dynamics attributable to static stripe order in La(1.275)Nd(0.6)Sr(0.125)CuO(4) or superconductivity in La(1.875)Sr(0.125)CuO(4) are confined to energies smaller than 100 cm(-1). An absorption peak in the low- omega conductivity of the Nd-doped compound is suggestive of localization effects due to the reduced dimensionality of static charge stripes. Neither superconductivity nor static stripe ordering has a noticeable effect on the depression of the scattering rate at omega<1000 cm(-1) characteristic of the pseudogap state in other classes of moderately doped cuprates.

16.
Phys Rev Lett ; 88(14): 147004, 2002 Apr 08.
Article in English | MEDLINE | ID: mdl-11955171

ABSTRACT

Since the nature of pairing interactions is manifested in the superconducting gap symmetry, the exact gap structure, particularly any deviation from the simple d(x(2)-y(2)) symmetry, would help in elucidating the pairing mechanism in high- T(c) cuprates. Anisotropic heat transport measurement in Bi(2)Sr(2)CaCu(2)O(8+delta) reveals that the quasiparticle populations are different for the two nodal directions and thus the gap structure must be uniquely anisotropic, suggesting that pairing is governed by interactions with a rather complicated anisotropy. Intriguingly, it is found that the "plateau" in the magnetic-field dependence of the thermal conductivity is observed only in the b-axis transport.

17.
Chaos ; 3(1): 63-72, 1993 Jan.
Article in English | MEDLINE | ID: mdl-12780015

ABSTRACT

This paper reports experimental observations of codimension-two heteroclinic bifurcations in an autonomous third-order electrical circuit. The paper also reports confirmations by computer simulations. In the laboratory experiments, a pair of programmable resistors are used in order to adjust two bifurcation parameters. In the associated two-parameter space, several codimension-one bifurcation sets are experimentally measured to capture codimension-two bifurcation structures. All of these bifurcation sets are numerically confirmed by exact bifurcation equations which are derived from piecewise-linear circuit dynamics.

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