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1.
Sci Rep ; 14(1): 2573, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38336981

ABSTRACT

To detect and track structural changes in atomic nuclei, the systematic study of nuclear levels with firm spin-parity assignments is important. While linear polarization measurements have been applied to determine the electromagnetic character of gamma-ray transitions, the applicable range is strongly limited due to the low efficiency of the detection system. The multi-layer Cadmium-Telluride (CdTe) Compton camera can be a state-of-the-art gamma-ray polarimeter for nuclear spectroscopy with the high position sensitivity and the detection efficiency. We demonstrated the capability to operate this detector as a reliable gamma-ray polarimeter by using polarized 847-keV gamma rays produced by the [Formula: see text]([Formula: see text]) reaction. By combining the experimental data and simulated calculations, the modulation curve for the gamma ray was successfully obtained. A remarkably high polarization sensitivity was achieved, compatible with a reasonable detection efficiency. Based on the obtained results, a possible future gamma-ray polarimetery is discussed.

2.
J Physiol Pharmacol ; 74(2)2023 Apr.
Article in English | MEDLINE | ID: mdl-37453095

ABSTRACT

Building a precise alternative neurotoxicological test is of great importance to respond to societal and ethical requirements. In this study, a new developmental neurotoxicity test (DNT) was established with the human neural progenitor cell line. ReNcell CX cells were exposed to neurotoxic chemicals (aphidicolin, hydroxyurea, cytosine arabinoside, 5-fluorouracil, and ochratoxin A) or non-neurotoxic chemicals (sodium gluconate, sodium bicarbonate, penicillin G, and saccharin). Propidium iodide (PI) was used to evaluate cell viability. BrdU and Ki-76 were employed to determine cell proliferation. Based on the cell viability and proliferation, mathematical models were built by linear discriminant analysis. Furthermore, the neurotoxic-considered chemicals inhibited cell cycle progression at the protein level, supporting the biomolecular rationale for the predictive model. Overall, these results show that the new test method can be used to determine the potential developmental neurotoxicants or new drug candidates.


Subject(s)
Neural Stem Cells , Neurotoxicity Syndromes , Humans , Ki-67 Antigen/metabolism , Neural Stem Cells/metabolism , Neurotoxicity Syndromes/metabolism , Cell Line
3.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Article in English | MEDLINE | ID: mdl-36332266

ABSTRACT

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

4.
Allergy ; 72(8): 1202-1211, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28029172

ABSTRACT

BACKGROUND: The identification of inflammatory asthma phenotypes, using sputum analysis, has proven its value in diagnosis and disease monitoring. However due to technical limitations of sputum analysis, there is a strong need for fast and noninvasive diagnostics. This study included the activation state of eosinophils and neutrophils in peripheral blood to phenotype and monitor asthma. OBJECTIVES: To (i) construct a multivariable model using the activation state of blood granulocytes, (ii) compare its diagnostic value with sputum eosinophilia as gold standard and (iii) validate the model in an independent patient cohort. METHODS: Clinical parameters, activation of blood granulocytes and sputum characteristics were assessed in 115 adult patients with asthma (training cohort/Utrecht) and 34 patients (validation cohort/Oxford). RESULTS: The combination of blood eosinophil count, fractional exhaled nitric oxide, Asthma Control Questionnaire, medication use, nasal polyposis, aspirin sensitivity and neutrophil/eosinophil responsiveness upon stimulation with formyl-methionyl-leucyl phenylalanine was found to identify sputum eosinophilia with 90.5% sensitivity and 91.5% specificity in the training cohort and with 77% sensitivity and 71% specificity in the validation cohort (relatively high percentage on oral corticosteroids [OCS]). CONCLUSIONS: The proposed prediction model identifies eosinophilic asthma without the need for sputum induction. The model forms a noninvasive and externally validated test to assess eosinophilic asthma in patients not on OCS.


Subject(s)
Asthma/blood , Asthma/diagnosis , Eosinophilia/blood , Eosinophils , Leukocyte Count , Adolescent , Adult , Aged , Asthma/metabolism , Asthma/therapy , Biomarkers , Exhalation , Female , Humans , Male , Middle Aged , Models, Statistical , Nitric Oxide , Phenotype , Prognosis , ROC Curve , Sputum/cytology , Sputum/immunology , Young Adult
5.
Phys Rev Lett ; 117(9): 092501, 2016 Aug 26.
Article in English | MEDLINE | ID: mdl-27610847

ABSTRACT

We report total absorption spectroscopy measurements of ^{92}Rb, ^{96gs}Y, and ^{142}Cs ß decays, which are the most important contributors to the high energy ν[over ¯]_{e} spectral shape in nuclear reactors. These three ß decays contribute 43% of the ν[over ¯]_{e} flux near 5.5 MeV emitted by nuclear reactors. This ν[over ¯]_{e} energy is particularly interesting due to spectral features recently observed in several experiments including the Daya Bay, Double Chooz, and RENO Collaborations. Measurements were conducted at Oak Ridge National Laboratory by means of proton-induced fission of ^{238}U with on-line mass separation of fission fragments and the Modular Total Absorption Spectrometer. We observe a ß-decay pattern that is similar to recent measurements of ^{92}Rb, with a ground-state to ground-state ß feeding of 91(3)%. We verify the ^{96gs}Y ground-state to ground-state ß feeding of 95.5(20)%. Our measurements substantially modify the ß-decay feedings of ^{142}Cs, reducing the ß feeding to ^{142}Ba states below 2 MeV by 32% when compared with the latest evaluations. Our results increase the discrepancy between the observed and the expected reactor ν[over ¯]_{e} flux between 5 and 7 MeV, the maximum excess increases from ∼10% to ∼12%.

6.
Phys Rev Lett ; 116(5): 052501, 2016 Feb 05.
Article in English | MEDLINE | ID: mdl-26894705

ABSTRACT

A candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction ^{4}He(^{8}He,^{8}Be) at 186 MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst) MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (^{8}He,^{8}Be) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently.

7.
Phys Rev Lett ; 114(25): 252501, 2015 Jun 26.
Article in English | MEDLINE | ID: mdl-26197123

ABSTRACT

The low-lying structure of the neutron-rich nucleus (50)Ar has been investigated at the Radioactive Isotope Beam Factory using in-beam γ-ray spectroscopy with (9)Be((54)Ca,(50)Ar+γ)X, (9)Be((55)Sc,(50)Ar+γ)X, and (9)Be((56)Ti,(50)Ar+γ)X multinucleon removal reactions at ∼220 MeV/u. A γ-ray peak at 1178(18) keV is reported and assigned as the transition from the first 2(+) state to the 0(+) ground state. A weaker, tentative line at 1582(38) keV is suggested as the 4(1)(+)→2(1)(+) transition. The experimental results are compared to large-scale shell-model calculations performed in the sdpf model space using the SDPF-MU effective interaction with modifications based on recent experimental data for exotic calcium and potassium isotopes. The modified Hamiltonian provides a satisfactory description of the new experimental results for (50)Ar and, more generally, reproduces the energy systematics of low-lying states in neutron-rich Ar isotopes rather well. The shell-model calculations indicate that the N=32 subshell gap in (50)Ar is similar in magnitude to those in (52)Ca and (54)Ti and, notably, predict an N=34 subshell closure in (52)Ar that is larger than the one recently reported in (54)Ca.

8.
Br J Cancer ; 111(3): 452-60, 2014 Jul 29.
Article in English | MEDLINE | ID: mdl-24921916

ABSTRACT

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are prognostic factors for various types of cancer. In this study, we assessed the association of NLR and PLR with the prognosis of small-cell lung cancer (SCLC) in patients who received the standard treatment. METHODS: We retrospectively reviewed patients who were diagnosed with SCLC and treated with platinum-based chemotherapy between July 2006 and October 2013 in Gyeongsang National University Hospital Regional Cancer Center and Changwon Samsung Hospital. RESULTS: In total, 187 patients were evaluated. Compared with low NLR (<4), high NLR (⩾4) at diagnosis was associated with poor performance status, advanced stage, and lower response rate. Median overall survival (OS) and progression-free survival (PFS) were worse in the high-NLR group (high vs low, 11.17 vs 9.20 months, P=0.019 and 6.90 vs 5.49 months, P=0.005, respectively). In contrast, PLR at diagnosis was not associated with OS or PFS (P=0.467 and P=0.205, respectively). In multivariate analysis, stage, lactate dehydrogenase, and NLR at diagnosis were independent prognostic factors for OS and PFS. CONCLUSIONS: NLR is easily measurable and reflects the SCLC prognosis. A future prospective study is warranted to confirm our results.


Subject(s)
Lung Neoplasms/immunology , Lymphocytes/immunology , Neutrophils/immunology , Small Cell Lung Carcinoma/immunology , Adult , Aged , Aged, 80 and over , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Lung Neoplasms/drug therapy , Lung Neoplasms/mortality , Lymphocyte Count , Male , Middle Aged , Multivariate Analysis , Platelet Count , Prognosis , Proportional Hazards Models , Retrospective Studies , Small Cell Lung Carcinoma/drug therapy , Small Cell Lung Carcinoma/mortality , Treatment Outcome
9.
Phys Rev Lett ; 113(26): 262502, 2014 Dec 31.
Article in English | MEDLINE | ID: mdl-25615314

ABSTRACT

Excited states in the N=102 isotones 166Gd and 164Sm have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for 166Gd and 164Sm, respectively. Based on the decay patterns and potential energy surface calculations, including ß6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of 166Gd and 164Sm (N=102) compared to 164Gd and 162Sm (N=100), respectively, presents evidence for the predicted deformed shell closure at N=100.

10.
Hernia ; 18(2): 305-10, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24370603

ABSTRACT

INTRODUCTION: Inguinal hernia is one of the most common ailments known to mankind. When symptomatic it can severely affect the patient's quality of life. Nevertheless, the vast majority of inguinal herniorrhaphies are elective and, therefore, not available to uninsured patients who do not have the financial wherewithal to pay for the operation. Using the Surgery on Sunday model developed in Kentucky, hernia repair for the underserved developed a free clinic for hernia surgery, based on institutional commitment to the poor as well as the volunteer efforts of medical students and hospital personnel at all levels. METHODS: After consulting with Surgery on Sunday personnel, HRFU determined the number of in need patients by consulting with local free clinic physicians. Second, and most time consuming, was the application for the Federal Tort Claims Act (FTCA) medical legal protection. Under this law, all in hospital credentialed volunteer professionals are medico-legally protected if the surgery is performed in an associated free clinic. After FTCA application re-writes and committee meetings to work out logistics of the pre-op clinic, the follow-up clinic, enlistment of other volunteers such as transporters, translators, housekeeping for the ORs, a pharmacist, registration personnel and creation of HRFU hospital forms we established a surgery date. A memorandum of understanding was drafted and an agreement letter with the hospital system was co-signed. Fourteen patients were seen in the pre-operative clinic and two were placed on waiting list. Patients were operated upon using 3 operating rooms and a volunteer staff of 4 surgeons, 4 anesthesia personnel and 13 nurses. RESULTS: No surgical complications were encountered intra-operatively or in the recovery room, and all patients were discharged by 2:30 p.m. 1 week post-operatively one patient had severe incisional pain, two had operative site swelling, but there was no evidence of infection or hematoma, and one had a distal sac fluid collection. All patients returned for follow-up and were appreciative of the care provided. The enthusiasm and participation of the patients and staff both pre-operatively, the day of surgery and postoperatively was outstanding. CONCLUSION: On the basis of this result HRFU is prepared to assist other US hernia specialists and their respective hospitals to make Surgery on Sunday a possibility in their community.


Subject(s)
Ambulatory Surgical Procedures/economics , Elective Surgical Procedures/economics , Hernia, Inguinal/surgery , Herniorrhaphy/economics , Medically Underserved Area , Medically Uninsured , Hernia, Inguinal/epidemiology , Humans , United States/epidemiology
11.
Nature ; 502(7470): 207-10, 2013 Oct 10.
Article in English | MEDLINE | ID: mdl-24108051

ABSTRACT

Atomic nuclei are finite quantum systems composed of two distinct types of fermion--protons and neutrons. In a manner similar to that of electrons orbiting in an atom, protons and neutrons in a nucleus form shell structures. In the case of stable, naturally occurring nuclei, large energy gaps exist between shells that fill completely when the proton or neutron number is equal to 2, 8, 20, 28, 50, 82 or 126 (ref. 1). Away from stability, however, these so-called 'magic numbers' are known to evolve in systems with a large imbalance of protons and neutrons. Although some of the standard shell closures can disappear, new ones are known to appear. Studies aiming to identify and understand such behaviour are of major importance in the field of experimental and theoretical nuclear physics. Here we report a spectroscopic study of the neutron-rich nucleus (54)Ca (a bound system composed of 20 protons and 34 neutrons) using proton knockout reactions involving fast radioactive projectiles. The results highlight the doubly magic nature of (54)Ca and provide direct experimental evidence for the onset of a sizable subshell closure at neutron number 34 in isotopes far from stability.

12.
Phys Rev Lett ; 109(18): 182501, 2012 Nov 02.
Article in English | MEDLINE | ID: mdl-23215274

ABSTRACT

Excited states in (38,40,42) Si nuclei have been studied via in-beam γ-ray spectroscopy with multinucleon removal reactions. Intense radioactive beams of ^{40}S and (44)S provided at the new facility of the RIKEN Radioactive Isotope Beam Factory enabled γ-γ coincidence measurements. A prominent γ line observed with an energy of 742(8) keV in (42) Si confirms the 2(+) state reported in an earlier study. Among the γ lines observed in coincidence with the 2^{+} → 0+ transition, the most probable candidate for the transition from the yrast 4(+) state was identified, leading to a 4(1)+) energy of 2173(14) keV. The energy ratio of 2.93(5) between the 2(1)+ and 4(1)(+) states indicates well-developed deformation in (42) Si at N = 28 and Z = 14. Also for 38,40)Si energy ratios with values of 2.09(5) and 2.56(5) were obtained. Together with the ratio for (42)Si, the results show a rapid deformation development of Si isotopes from N = 24 to N = 28.

13.
Phys Rev Lett ; 106(20): 202501, 2011 May 20.
Article in English | MEDLINE | ID: mdl-21668223

ABSTRACT

The low-lying states in ¹°6Zr and ¹°8Zr have been investigated by means of ß-γ and isomer spectroscopy at the radioactive isotope beam factory (RIBF), respectively. A new isomer with a half-life of 620 ± 150 ns has been identified in ¹°8Zr. For the sequence of even-even Zr isotopes, the excitation energies of the first 2⁺ states reach a minimum at N = 64 and gradually increase as the neutron number increases up to N = 68, suggesting a deformed subshell closure at N = 64. The deformed ground state of ¹°8Zr indicates that a spherical subshell gap predicted at N = 70 is not large enough to change the ground state of ¹°8Zr to the spherical shape. The possibility of a tetrahedral shape isomer in ¹°8Zr is also discussed.

14.
Phys Rev Lett ; 106(5): 052502, 2011 Feb 04.
Article in English | MEDLINE | ID: mdl-21405387

ABSTRACT

The ß-decay half-lives of 38 neutron-rich isotopes from (36)Kr to (43)Tc have been measured; the half-lives of (100)Kr, (103-105)Sr, (106-108)Y, (108-110)Zr, (111,112)Nb, (112-115)Mo, and (116,117)Tc are reported here. The results when compared with previous standard models indicate an overestimation in the predicted half-lives by a factor of 2 or more in the A≈110 region. A revised model based on the second generation gross theory of ß decay better predicts the measured half-lives and suggests a more rapid flow of the rapid neutron-capture process (r-matter flow) through this region than previously predicted.

16.
Transplant Proc ; 38(6): 1825-6, 2006.
Article in English | MEDLINE | ID: mdl-16908294

ABSTRACT

PURPOSE: The authors have previously demonstrated that the neuropeptide bombesin (BBS) prevented allograft mucosal atrophy under tacrolimus (TRL) immunosuppression for rats small bowel transplantation (SBT). The present study investigated whether BBS had immunosuppressive effects on small bowel allografts. METHODS: Allogeneic SBT was performed heterotopically in rats (n = 12) that received daily administration of 0.1 mg/kg/d TRL from postoperative day 0 to day 14. Rats divided into two groups of six rats each were administered BBS or normal saline as a control. Biopsy of the allograft was performed from the stomal site on postoperative days 6, 10, and 14. The state of the graft mucosal villi was evaluated by H & E staining and TUNEL immunohistochemistry. RESULTS: By postoperative day 14, extensive mucosal destruction accompanied by heavy transmural cellular infiltration had developed in the control group. Lymphocytes and plasma cells infiltrated the lamina propria of the allograft without the distorting villous architecture in the BBS group. The TUNEL index of graft mucosa in the control group was 1.26% +/- 0.37% (mean +/- SD) and that in the BBS group, 0.59% +/- 0.20%, respectively (p < .001). CONCLUSION: This study demonstrated an immunosuppressive effect of bombesin on transplanted allografts, which might dramatically reduce the dose of TRL required for postoperative immunosuppression.


Subject(s)
Amino Acids/metabolism , Intestinal Absorption/physiology , Intestine, Small/transplantation , Neurosecretory Systems/immunology , Transplantation, Homologous/immunology , Animals , Glycine/metabolism , Kinetics , Male , Models, Animal , Rats , Rats, Wistar
17.
Brain Inj ; 19(9): 739-42, 2005 Aug 20.
Article in English | MEDLINE | ID: mdl-16195188

ABSTRACT

OBJECTIVE: To report a case of deep vein thrombosis (DVT) in a tetraparesic patient, a member of a population in which DVT is reportedly rare. CASE REPORT: A 36-year old tetraparesic resident of a developmental centre suddenly developed swelling of one leg. Her plasma D-dimer level was 751 (normal<500) ng ml-1. A Doppler ultrasound revealed femoral vein thrombosis. She usually spent 10-12 hours daily in a chair. For menstrual problems, she had received oral contraceptives (OC) for 23 months. She had no other genetic or acquired predisposition to DVT. She was anti-coagulated for 6 months and the OC was discontinued. She recovered without complications. Her DVT was probably caused by her immobility, prolonged sitting and OC. CONCLUSION: DVT may develop in tetraparesic patients if they are exposed to additional prothrombotic factors. OC should be prescribed cautiously to such people. Relevant literature, prevention and treatment are discussed.


Subject(s)
Intellectual Disability/complications , Quadriplegia/complications , Venous Thrombosis/complications , Adult , Contraceptives, Oral/adverse effects , Female , Femoral Vein/diagnostic imaging , Humans , Menstruation Disturbances/drug therapy , Ultrasonography , Venous Thrombosis/diagnostic imaging
18.
Clin Genet ; 67(2): 160-5, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15679828

ABSTRACT

Sensorineural hearing loss associated with enlargement of the vestibular aqueduct (EVA) can be associated with mutations of the SLC26A4 gene. In western populations, less than one-half of the affected individuals with EVA have two mutant SLC26A4 alleles, and EVA is frequently caused by unknown genetic or environmental factors alone or in combination with a single SLC26A4 mutation as part of a complex trait. In this study, we ascertained 26 Korean probands with EVA and performed nucleotide sequence analysis to detect SLC26A4 mutations. All subjects had bilateral EVA, and 20 of 26 were sporadic (simplex) cases. Fourteen different mutations were identified, including nine novel mutations. Five mutations were recurrent and accounted for 80% of all mutant alleles, providing a basis for the design and interpretation of cost-efficient mutation detection algorithms. Two mutant alleles were identified in 21 (81%), one mutant allele was detected in three (11%), and zero mutant allele was detected in two (8%) of 26 probands. The high proportion of Korean probands with two SLC26A4 mutations may reflect a reduced frequency of other genetic or environmental factors causing EVA in comparison to western populations.


Subject(s)
Hearing Loss/ethnology , Hearing Loss/genetics , Membrane Transport Proteins/genetics , Polymorphism, Genetic , Vestibular Aqueduct/pathology , Adolescent , Adult , Biological Transport , Case-Control Studies , Child , Child, Preschool , DNA Mutational Analysis , Female , Humans , Korea , Male , Sulfate Transporters , Sulfates
20.
FEMS Microbiol Lett ; 202(1): 97-102, 2001 Aug 07.
Article in English | MEDLINE | ID: mdl-11506914

ABSTRACT

Forty one strains isolated from 21 samples of various mushroom composts in Korea were analyzed by 16S rRNA gene sequencing to investigate the phylogenetic diversity of thermophilic actinomycetes. The 25 strains of thermophilic actinomycete isolates were related to the five genera, Pseudonocardia, Saccharomonospora, Saccharopolyspora, Streptomyces, and Thermobifida, within the order Actinomycetales, and 16 strains were classified into the genus Thermoactinomyces within the family Bacillaceae. Most of 41 isolates were encompassed by two genera, Streptomyces and Thermoactinomyces, that were isolated mainly in composts prepared from waste cotton and hay, respectively. Among them, M104 and M109 were placed in distinct taxonomic positions although these strains formed phylogenetic lineages related to the genus Streptomyces and to the family Streptosporangiaceae, respectively. Therefore, a phenetic and genetic characterization of these strains will be needed to pinpoint their taxonomic position.


Subject(s)
Agaricales , DNA, Ribosomal/genetics , Genes, Bacterial/genetics , Micromonosporaceae/classification , Micromonosporaceae/genetics , Phylogeny , RNA, Ribosomal, 16S/genetics , Genetic Variation/genetics , Korea , Mutation/genetics , Sequence Analysis, DNA , Waste Products
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