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1.
Phys Rev Lett ; 129(14): 142502, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36240396

RESUMO

The root mean square radii of the proton density distribution in ^{16-24}O derived from measurements of charge changing cross sections with a carbon target at ∼900A MeV together with the matter radii portray thick neutron skin for ^{22-24}O despite ^{22,24}O being doubly magic. Imprints of the shell closures at N=14 and 16 are reflected in local minima of their proton radii that provide evidence for the tensor interaction causing them. The radii agree with ab initio calculations employing the chiral NNLO_{sat} interaction, though skin thickness predictions are challenged. Shell model predictions agree well with the data.


Assuntos
Nêutrons , Prótons , Carbono
2.
Phys Rev Lett ; 124(10): 102501, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216444

RESUMO

Interaction cross sections for ^{42-51}Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.

3.
Phys Rev Lett ; 124(22): 222504, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32567915

RESUMO

We report the measurement of reaction cross sections (σ_{R}^{ex}) of ^{27,29}F with a carbon target at RIKEN. The unexpectedly large σ_{R}^{ex} and derived matter radius identify ^{29}F as the heaviest two-neutron Borromean halo to date. The halo is attributed to neutrons occupying the 2p_{3/2} orbital, thereby vanishing the shell closure associated with the neutron number N=20. The results are explained by state-of-the-art shell model calculations. Coupled-cluster computations based on effective field theories of the strong nuclear force describe the matter radius of ^{27}F but are challenged for ^{29}F.

4.
Helminthologia ; 57(3): 288-292, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32855617

RESUMO

Migration of Baylisascaris potosis larvae in different mouse strains were compared, and infectivity of the persisting larvae in mice tissues were investigated. Five strains of mice, BALB/c, C57BL/6, AKR, B10.BR, and ICR were inoculated with 1,000 B. potosis eggs/mouse, and necropsied at week 13 post inoculation (PI). The other uninfected ICR mice (secondary host) were inoculated with 43 larvae/ mouse recovered from mice at week 13 PI with eggs, and necropsied at day 21 PI. Larvae in organs or tissues were counted at necropsy. One AKR mouse showed torticollis and circling at day 56 PI. At necropsy at week 13 PI, larvae were recovered from all mice. A mean total larvae recovered were 124.1 (n=40). Majority of larvae were found in the carcass (mean 113.9) and some in the viscera (mean 9.9). Zero to 1 larva were found in the brain or eyes of some mice. There were no differences among the mouse strains in the number of larvae, except in the viscera; more larvae were seen in BALB/c or ICR than in B10.BR mice. No larvae were found in the secondary host mice. Present study demonstrated that B. potosis larvae migrate well in the carcass of any strains of mice, however, the tissue larvae did not infect the secondary host. Results of our present study suggest that B. potosis larvae is less aggressive for the nervous tissue migration than that of B. procyonis larvae which is commonly known to migrate in central nervous system of mammals and birds.

5.
Phys Rev Lett ; 123(9): 092502, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31524489

RESUMO

The most remote isotope from the proton dripline (by 4 atomic mass units) has been observed: ^{31}K. It is unbound with respect to three-proton (3p) emission, and its decays have been detected in flight by measuring the trajectories of all decay products using microstrip detectors. The 3p emission processes have been studied by the means of angular correlations of ^{28}S+3p and the respective decay vertices. The energies of the previously unknown ground and excited states of ^{31}K have been determined. This provides its 3p separation energy value S_{3p} of -4.6(2) MeV. Upper half-life limits of 10 ps of the observed ^{31}K states have been derived from distributions of the measured decay vertices.

6.
Oral Dis ; 23(2): 199-209, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27868311

RESUMO

OBJECTIVE: Ameloblastoma (AM) shows locally invasive behaviour. However, biological investigations regarding regulation of gene expression associated with AM pathological features are difficult to perform, because AM cells can be passaged for a few generations due to senescence. We report a newly established immortalized AM cell line, AMB cells, by transfection with human telomerase reverse transcriptase (hTERT). Furthermore, we examined whether TNF-α modulates bone resorption-related genes, IL-6 and MMP-9 in cooperation with TGF-ß or IFN-γ. MATERIALS AND METHODS: Following transfection of an hTERT expression vector into AM cells using a non-viral method, the effects of cytokines on the expressions of IL-6 and MMP-9 mRNA were examined using real-time PCR. TNF-α-induced NF-κB activity was examined by western blotting and transcription factor assays. RESULTS: AMB cells continued to grow for more than 100 population doublings. Stimulation with TNF-α increased IL-6 and MMP-9 mRNA expressions, as well as NF-κB activation. Furthermore, TGF-ß and IFN-γ dramatically increased TNF-α-mediated expressions of MMP-9 and IL-6 mRNA, respectively, while those responses were suppressed by NF-κB inhibitor. CONCLUSION: We established an immortalized AM cell line by hTERT transfection. TNF-α-mediated regulation of MMP-9 and IL-6 via NF-κB may play an important role in the pathological behaviour of AMs, such as bone resorption.


Assuntos
Ameloblastoma/genética , Expressão Gênica/efeitos dos fármacos , Interleucina-6/genética , Neoplasias Maxilomandibulares/genética , Metaloproteinase 9 da Matriz/genética , Fator de Necrose Tumoral alfa/farmacologia , Adulto , Ameloblastoma/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular/genética , Feminino , Humanos , Interferon gama/farmacologia , Neoplasias Maxilomandibulares/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Nitrilas/farmacologia , RNA Mensageiro/metabolismo , Sulfonas/farmacologia , Telomerase/genética , Transfecção , Fator de Crescimento Transformador beta/farmacologia
7.
Phys Rev Lett ; 117(10): 102501, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27636470

RESUMO

Proton radii of ^{12-19}C densities derived from first accurate charge changing cross section measurements at 900A MeV with a carbon target are reported. A thick neutron surface evolves from ∼0.5 fm in ^{15}C to ∼1 fm in ^{19}C. The halo radius in ^{19}C is found to be 6.4±0.7 fm as large as ^{11}Li. Ab initio calculations based on chiral nucleon-nucleon and three-nucleon forces reproduce the radii well.

8.
Phys Rev Lett ; 117(20): 202501, 2016 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-27886506

RESUMO

Excitation spectra of ^{11}C are measured in the ^{12}C(p,d) reaction near the η^{'} emission threshold. A proton beam extracted from the synchrotron SIS-18 at GSI with an incident energy of 2.5 GeV impinges on a carbon target. The momenta of deuterons emitted at 0° are precisely measured with the fragment separator (FRS) operated as a spectrometer. In contrast to theoretical predictions on the possible existence of deeply bound η^{'}-mesic states in carbon nuclei, no distinct structures are observed associated with the formation of bound states. The spectra are analyzed to set stringent constraints on the formation cross section and on the hitherto barely known η^{'}-nucleus interaction.

9.
Phys Rev Lett ; 115(20): 202501, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26613434

RESUMO

Previously unknown isotopes (30)Ar and (29)Cl have been identified by measurement of the trajectories of their in-flight decay products (28)S+p+p and (28)S+p, respectively. The analysis of angular correlations of the fragments provided information on decay energies and the structure of the parent states. The ground states of (30)Ar and (29)Cl were found at 2.25(-0.10)(+0.15) and 1.8±0.1 MeV above the two- and one-proton thresholds, respectively. The lowest states in (30)Ar and (29)Cl point to a violation of isobaric symmetry in the structure of these unbound nuclei. The two-proton decay has been identified in a transition region between simultaneous two-proton and sequential proton emissions from the (30)Ar ground state, which is characterized by an interplay of three-body and two-body decay mechanisms. The first hint of a fine structure of the two-proton decay of (30)Ar*(2(+)) has been obtained by detecting two decay branches into the ground and first-excited states of the (28)S fragment.

10.
Oral Dis ; 21(1): 106-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24495175

RESUMO

OBJECTIVE: Itraconazole (ICZ) has a broad spectrum of antifungal activity including a wide range of Candida spp. TNF-α, an inflammatory cytokine associated with Th1-mediated oral inflammatory disease, enhances inflammatory mediators, such as CXCR3-agonistic chemokines including CXCL10. We examined the anti-inflammatory potential of ICZ against TNF-α-induced chemokines in oral fibroblasts. MATERIALS AND METHODS: We investigated the effects of ICZ on mRNA expressions of various TNF-α-induced chemokines in immortalized oral keratinocytes (RT7) and oral fibroblasts (GT1) using quantitative PCR analysis. Subsequently, the effects of ICZ and fluconazole (FLZ) on TNF-α-induced CXCL10 proteins in GT1 and primary fibroblasts were examined using enzyme-linked immunosorbent assays (ELISA). The effect of ICZ on signal transduction protein phosphorylation involved in CXCL10 production from TNF-α-stimulated GT1 was examined by western blotting. RESULTS: ICZ inhibited TNF-α-induced CXCL10 mRNA in GT1, but not RT7. Although ICZ did not affect TNF-α-induced IL-8 mRNA, the mRNAs of TNF-α-induced CXCR3-agonistic chemokines such as CXCL9 and CXCL11 were inhibited by ICZ in GT1. TNF-α-induced CXCL10 protein production in GT1 and primary fibroblasts was inhibited by ICZ, but not FLZ. Finally, ICZ inhibited TNF-α-induced phosphorylation of c-JUN, which is related to CXCL10 production by TNF-α-stimulated GT1. CONCLUSION: ICZ may be useful as therapy for Th1-mediated oral inflammatory disease.


Assuntos
Antifúngicos/farmacologia , Quimiocina CXCL10/biossíntese , Fibroblastos/fisiologia , Itraconazol/farmacologia , Queratinócitos/fisiologia , Boca/citologia , Fator de Necrose Tumoral alfa/farmacologia , Western Blotting , Linhagem Celular , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fluconazol/farmacologia , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Phys Rev Lett ; 112(14): 142501, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24765946

RESUMO

The halo structure of 31Ne is studied using 1n-removal reactions on C and Pb targets at 230 MeV/nucleon. A combined analysis of the cross sections of these nuclear and Coulomb dominated reactions that feed directly the 30Ne ground-state reveals 31Ne to have a small neutron separation energy, 0.15(-0.10)(+0.16) MeV, and spin-parity 3/2-. Consistency of the data with reaction and large-scale shell-model calculations identifies 31Ne as deformed and having a significant p-wave halo component, suggesting that halos are more frequent occurrences at the neutron drip line.

12.
Phys Rev Lett ; 113(13): 132501, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25302882

RESUMO

The first determination of radii of point proton distribution (proton radii) of (12-17)B from charge-changing cross sections (σ(CC)) measurements at the FRS, GSI, Darmstadt is reported. The proton radii are deduced from a finite-range Glauber model analysis of the σ(CC). The radii show an increase from ¹³B to ¹7B and are consistent with predictions from the antisymmetrized molecular dynamics model for the neutron-rich nuclei. The measurements show the existence of a thick neutron surface with neutron-proton radius difference of 0.51(0.11) fm in ¹7B.

13.
Phys Rev Lett ; 111(21): 212502, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313483

RESUMO

Neutron-rich N=22, 24, 26 magnesium isotopes were studied via in-beam γ-ray spectroscopy at the RIKEN Radioactive Isotope Beam Factory following secondary fragmentation reactions on a carbon target at ≈200 MeV/nucleon. In the one- and two-proton removal channels from 39Al and 40Si beams, two distinct γ-ray transitions were observed in 38Mg, while in the one-proton removal reaction from 37Al a new transition was observed in addition to the known 2(1)(+)→0(g.s.)(+) decay. From the experimental systematics and comparison to theoretical predictions it is concluded that the transitions belong to the 2(1)(+)→0(g.s.)(+) and 4(1)(+)→2(1)(+) decays in 36Mg and 38Mg, respectively. For 34Mg, previously reported 2(1)(+) and 4(1)(+) level energies were remeasured. The deduced E(4(1)(+))/E(2(1)(+)) ratios for 34,36,38Mg of 3.14(5), 3.07(5), and 3.07(5) are almost identical and suggest the emergence of a large area of deformation extending from the N=20 to the N=28 shell quenching.

14.
Phys Rev Lett ; 109(18): 182501, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23215274

RESUMO

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.

15.
Oral Dis ; 18(8): 756-62, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22642601

RESUMO

OBJECTIVES: An odontoma, which shows proliferating odontogenic epithelium and mesenchymal tissue, is one of the most common odontogenic tumors encountered. These are commonly found in tooth-bearing regions, although the etiology remains unknown. There are no previous reports of an established line of immortalized human odontoma cells. METHODS: Using odontoma fragments obtained from a girl treated at our department, we established an immortalized human odontoma cell line and investigated cell morphology, dynamic proliferation, the presence of contamination, and karyotype. Moreover, cell characterization was examined using osteogenic and odontogenic markers. RESULTS: We successfully established a mesenchymal odontoma cell (mOd cells). The cells were found to be fibroblastic and had a high level of telomerase activity. Cell growth was confirmed after more than 200 population doublings without significant growth retardation. mOd cells expressed mRNA for differentiation markers, including collagen type I (COLI), alkaline phosphatase, bone sialoprotein, osteopontin, osteocalcin, cementum-derived protein (CP-23), dentin sialophosphoprotein (DSPP), and distal-less homeobox 3 (DLX3), as well as bone morphogenetic proteins (BMPs). In addition, they showed a high level of calcified nodule formation activity in vitro. CONCLUSIONS: We successfully established a cell line that may be useful for investigating the mechanisms of normal odontogenesis as well as characteristics of odontoma tumors.


Assuntos
Linhagem Celular Tumoral , Mesoderma/patologia , Odontoma/patologia , Adolescente , Adulto , Idoso , Fosfatase Alcalina/análise , Biomarcadores/análise , Proteínas Morfogenéticas Ósseas/análise , Calcificação Fisiológica/fisiologia , Técnicas de Cultura de Células , Proliferação de Células , Forma Celular , Criança , Pré-Escolar , Colágeno Tipo I/análise , Proteínas da Matriz Extracelular/análise , Feminino , Fibroblastos/patologia , Proteínas de Homeodomínio/análise , Humanos , Sialoproteína de Ligação à Integrina/análise , Cariótipo , Pessoa de Meia-Idade , Odontoma/genética , Osteocalcina/análise , Osteopontina/análise , Fosfoproteínas/análise , Proteínas/análise , Sialoglicoproteínas/análise , Telomerase/análise , Fatores de Transcrição/análise , Adulto Jovem
16.
Phys Rev Lett ; 104(6): 062701, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-20366816

RESUMO

Reaction cross sections (sigma(R)) for 19C, 20C and the drip-line nucleus 22C on a liquid hydrogen target have been measured at around 40A MeV by a transmission method. A large enhancement of sigma(R) for 22C compared to those for neighboring C isotopes was observed. Using a finite-range Glauber calculation under an optical-limit approximation the rms matter radius of 22C was deduced to be 5.4+/-0.9 fm. It does not follow the systematic behavior of radii in carbon isotopes with N < or = 14, suggesting a neutron halo. It was found by an analysis based on a few-body Glauber calculation that the two-valence neutrons in 22C preferentially occupy the 1s(1/2) orbital.

17.
Oral Dis ; 16(5): 438-44, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20233319

RESUMO

OBJECTIVE: The purpose of this study was to develop a graft material made of gingival fibroblasts cultured in animal-free medium (HFDM1). METHODS: We examined the effects of human serum (HS) on cell growth and wound healing capability, demonstrated by cytokine production, of gingival fibroblasts cultured in HFDM1. Subsequently, the capability of fibroblasts cultured in HFDM1 with 2% HS to promote the healing of skin defects was evaluated using nude mice. RESULTS: The proliferation of human gingival fibroblasts was increased when HS at a concentration of 0.5-2% was added to HFDM1. Wound healing cytokines, including transforming growth factor-beta, keratinocyte growth factor, hepatocyte growth factor, vascular endothelial growth factor, and IL-6 produced by gingival fibroblasts were increased by adding 2% HS to HFDM1. In addition, gingival fibroblasts cultured in HFDM1 with 2% HS improved wound healing of mouse skin defects as well as those cultured in Dulbecco's modified Eagle's medium with 10% fetal calf serum. CONCLUSION: Gingival fibroblasts cultured in HFDM1 with 2% HS may be useful as a graft material for reconstruction.


Assuntos
Meios de Cultura , Fibroblastos/fisiologia , Gengiva/fisiologia , Animais , Sangue , Técnicas de Cultura de Células , Proliferação de Células , Citocinas/análise , Fator 7 de Crescimento de Fibroblastos/análise , Fibroblastos/transplante , Gengiva/citologia , Gengiva/transplante , Fator de Crescimento de Hepatócito/análise , Humanos , Interleucina-6/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dermatopatias/cirurgia , Engenharia Tecidual/métodos , Fator de Crescimento Transformador beta/análise , Fator A de Crescimento do Endotélio Vascular/análise , Cicatrização/fisiologia
18.
J Oral Rehabil ; 37(2): 131-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20002529

RESUMO

Resonance frequency analysis (RFA) was introduced as a method for measuring implant stability more than a decade ago. Implant stability quotient (ISQ) values obtained using a recently introduced wireless RFA device have made it possible to evaluate stability in a non-invasive technique; however, there are few studies of the factors that affect ISQ values determined using this device. The aim of the present study was to evaluate the association between ISQ values determined by wireless RFA and various factors related to dental implant stability using a pig cortical bone model. Dental implants (Replace) Select Tapered implants) with a length of 10 mm were placed into pig cortical bone samples, then, ISQ values were determined using wireless RFA under various conditions (probe orientation, diameter of implant, insertion torque and peri-implant bone loss). The results of this study showed that ISQ values were not affected by the direction of the probe from parallel to perpendicular to the long axis of the pig bone or to the smart peg. In addition, the diameter of the implant did not have a significant effect on the measured ISQ values. Statistically significant correlations were found between insertion torque and ISQ values (Spearman's test, P < 0.05), and lower ISQ values were observed for deeper peri-implant vertical defects (Mann-Whitney U-test, P < 0.05). A wireless RFA device appears to be useful for measuring implant stability within the limits of the present in vitro study.


Assuntos
Osso e Ossos/fisiologia , Implantes Dentários , Retenção em Prótese Dentária , Magnetismo/instrumentação , Animais , Reabsorção Óssea/fisiopatologia , Planejamento de Prótese Dentária , Desenho de Equipamento , Modelos Animais , Propriedades de Superfície , Suínos , Torque
19.
J Dent Res ; 99(3): 271-276, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31977282

RESUMO

Chronic nonbacterial osteomyelitis is a rare bone disorder that can be found in the jaw. It is often associated with systemic conditions, including autoimmune deficiencies. However, little is known about how the genetic and immunologic background of patients influences the disease. Here, we focus on human leukocyte antigen (HLA), killer cell immunoglobulin-like receptors (KIRs), and their specific combinations that have been difficult to analyze owing to their high diversity. We employed a recently developed technology of simultaneous typing of HLA alleles and KIR haplotype and investigated alleles of the 35 HLA loci and KIR haplotypes composed of centromeric and telomeric motifs in 18 cases and 18 controls for discovery and 472 independent controls for validation. We identified an amino acid substitution of threonine at position 94 of HLA-C in combination with the telomeric KIR genotype of haplotype tA01/tB01 that had significantly higher frequency (>20%) in the case population than in both control populations. Multiple logistic regression analysis based on a dominant model with adjustments for age and sex revealed and validated its statistical significance and high predictive accuracy (C-statistic ≥0.85). Structure-based analysis revealed that the combination of the amino acid change in HLA-C and the telomeric genotype tA01/tB01 could be associated with lower stability of HLA-C. This is the first case-control study of a rare disease that employed the latest sequencing technology enabling simultaneous typing and investigated amino acid polymorphisms at HLA loci in combination with KIR haplotype.


Assuntos
Osteomielite , Estudos de Casos e Controles , Frequência do Gene , Estudos de Associação Genética , Genótipo , Haplótipos/genética , Humanos , Osteomielite/genética , Receptores KIR/genética
20.
Phys Rev Lett ; 103(26): 262501, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20366309

RESUMO

The cross sections for single-neutron removal from the very neutron-rich nucleus 31Ne on Pb and C targets have been measured at 230 MeV/nucleon using the RIBF facility at RIKEN. The deduced large Coulomb breakup cross section of 540(70) mb is indicative of a soft E1 excitation. Comparison with direct-breakup model calculations suggests that the valence neutron of 31Ne occupies a low-l orbital (most probably 2p(3/2)) with a small separation energy (S(n) approximately < 0.8 MeV), instead of being predominantly in the 1f(7/2) orbital as expected from the conventional shell ordering. These findings suggest that 31Ne is the heaviest halo system known.

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