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1.
Phys Rev Lett ; 132(15): 152503, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38682970

RESUMEN

The first complete measurement of the ß-decay strength distribution of _{17}^{45}Cl_{28} was performed at the Facility for Rare Isotope Beams (FRIB) with the FRIB Decay Station Initiator during the second FRIB experiment. The measurement involved the detection of neutrons and γ rays in two focal planes of the FRIB Decay Station Initiator in a single experiment for the first time. This enabled an analytical consistency in extracting the ß-decay strength distribution over the large range of excitation energies, including neutron unbound states. We observe a rapid increase in the ß-decay strength distribution above the neutron separation energy in _{18}^{45}Ar_{27}. This was interpreted to be caused by the transitioning of neutrons into protons excited across the Z=20 shell gap. The SDPF-MU interaction with reduced shell gap best reproduced the data. The measurement demonstrates a new approach that is sensitive to the proton shell gap in neutron rich nuclei according to SDPF-MU calculations.

2.
Phys Rev Lett ; 131(9): 092501, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721823

RESUMEN

The last proton bound calcium isotope ^{35}Ca has been studied for the first time, using the ^{37}Ca(p,t)^{35}Ca two neutron transfer reaction. The radioactive ^{37}Ca nuclei, produced by the LISE spectrometer at GANIL, interacted with the protons of the liquid hydrogen target CRYPTA, to produce tritons t that were detected in the MUST2 detector array, in coincidence with the heavy residues Ca or Ar. The atomic mass of ^{35}Ca and the energy of its first 3/2^{+} state are reported. A large N=16 gap of 4.61(11) MeV is deduced from the mass measurement, which together with other measured properties, makes ^{36}Ca a doubly magic nucleus. The N=16 shell gaps in ^{36}Ca and ^{24}O are of similar amplitude, at both edges of the valley of stability. This feature is discussed in terms of nuclear forces involved, within state-of-the-art shell model calculations. Even though the global agreement with data is quite convincing, the calculations underestimate the size of the N=16 gap in ^{36}Ca by 840 keV.

3.
Phys Rev Lett ; 130(24): 242501, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37390416

RESUMEN

Excited-state spectroscopy from the first experiment at the Facility for Rare Isotope Beams (FRIB) is reported. A 24(2)-µs isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV γ rays in coincidence with ^{32}Na nuclei. This is the only known microsecond isomer (1 µs≤T_{1/2}<1 ms) in the region. This nucleus is at the heart of the N=20 island of shape inversion and is at the crossroads of the spherical shell-model, deformed shell-model, and ab initio theories. It can be represented as the coupling of a proton hole and neutron particle to ^{32}Mg, ^{32}Mg+π^{-1}+ν^{+1}. This odd-odd coupling and isomer formation provides a sensitive measure of the underlying shape degrees of freedom of ^{32}Mg, where the onset of spherical-to-deformed shape inversion begins with a low-lying deformed 2^{+} state at 885 keV and a low-lying shape-coexisting 0_{2}^{+} state at 1058 keV. We suggest two possible explanations for the 625-keV isomer in ^{32}Na: a 6^{-} spherical shape isomer that decays by E2 or a 0^{+} deformed spin isomer that decays by M2. The present results and calculations are most consistent with the latter, indicating that the low-lying states are dominated by deformation.


Asunto(s)
Núcleo Celular , Corazón , Isótopos , Neutrones
4.
Phys Rev Lett ; 131(21): 212501, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38072612

RESUMEN

The cluster structure of the neutron-rich isotope ^{10}Be has been probed via the (p,pα) reaction at 150 MeV/nucleon in inverse kinematics and in quasifree conditions. The populated states of ^{6}He residues were investigated through missing mass spectroscopy. The triple differential cross section for the ground-state transition was extracted for quasifree angle pairs (θ_{p},θ_{α}) and compared to distorted-wave impulse approximation reaction calculations performed in a microscopic framework using successively the Tohsaki-Horiuchi-Schuck-Röpke product wave function and the wave function deduced from antisymmetrized molecular dynamics calculations. The remarkable agreement between calculated and measured cross sections in both shape and magnitude validates the molecular structure description of the ^{10}Be ground-state, configured as an α-α core with two valence neutrons occupying π-type molecular orbitals.

5.
Phys Rev Lett ; 129(12): 122501, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36179171

RESUMEN

Detailed spectroscopy of the neutron-deficient nucleus ^{36}Ca was obtained up to 9 MeV using the ^{37}Ca(p,d)^{36}Ca and the ^{38}Ca(p,t)^{36}Ca transfer reactions. The radioactive nuclei, produced by the LISE spectrometer at GANIL, interacted with the protons of the liquid hydrogen target CRYPTA, to produce light ejectiles (the deuteron d or triton t) that were detected in the MUST2 detector array, in coincidence with the heavy residues identified by a zero-degree detection system. Our main findings are (i) a similar shift in energy for the 1_{1}^{+} and 2_{1}^{+} states by about -250 keV, as compared with the mirror nucleus ^{36}S; (ii) the discovery of an intruder 0_{2}^{+} state at 2.83(13) MeV, which appears below the first 2^{+} state, in contradiction with the situation in ^{36}S; and (iii) a tentative 0_{3}^{+} state at 4.83(17) MeV, proposed to exhibit a bubble structure with two neutron vacancies in the 2s_{1/2} orbit. The inversion between the 0_{2}^{+} and 2_{1}^{+} states is due to the large mirror energy difference (MED) of -516(130) keV for the former. This feature is reproduced by shell model calculations, using the sd-pf valence space, predicting an almost pure intruder nature for the 0_{2}^{+} state, with two protons (neutrons) being excited across the Z=20 magic closure in ^{36}Ca (^{36}S). This mirror system has the largest MEDs ever observed, if one excludes the few cases induced by the effect of the continuum.

6.
Phys Rev Lett ; 128(15): 152701, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35499908

RESUMEN

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and ß-delayed neutron emission probability, P_{1 n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

7.
Phys Rev Lett ; 129(21): 212501, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36461950

RESUMEN

New half-lives for exotic isotopes approaching the neutron drip-line in the vicinity of N∼28 for Z=12-15 were measured at the Facility for Rare Isotope Beams (FRIB) with the FRIB decay station initiator. The first experimental results are compared to the latest quasiparticle random phase approximation and shell-model calculations. Overall, the measured half-lives are consistent with the available theoretical descriptions and suggest a well-developed region of deformation below ^{48}Ca in the N=28 isotones. The erosion of the Z=14 subshell closure in Si is experimentally confirmed at N=28, and a reduction in the ^{38}Mg half-life is observed as compared with its isotopic neighbors, which does not seem to be predicted well based on the decay energy and deformation trends. This highlights the need for both additional data in this very exotic region, and for more advanced theoretical efforts.

8.
Phys Rev Lett ; 124(6): 065101, 2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32109113

RESUMEN

The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.

9.
Scand J Rheumatol ; 47(5): 364-370, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29804492

RESUMEN

OBJECTIVE: To prospectively investigate the effect of tocilizumab (TCZ) on the levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), as a predictor of congestive heart failure (CHF) in patients with active rheumatoid arthritis (RA). METHOD: Seventy patients with RA (median age 59 years, 86% female) free of cardiovascular disease were treated with TCZ and followed for 24 weeks. The NT-proBNP levels were measured at baseline and week 24. Thirty healthy controls were included for comparison of normal NT-proBNP levels with those of RA patients. RESULTS: The NT-proBNP level was significantly higher in patients with RA than in controls (median 42.5 pg/mL vs 109.0 pg/mL, p < 0.001). NT-proBNP levels decreased by 63% over the 24 weeks of TCZ treatment. Multiple linear regression analysis indicated that the percentage change in the NT-proBNP level was significantly associated with that of the Simplified Disease Activity Index (ß = 0.356, p = 0.014), even after adjusting for the levels of rheumatoid factor, duration of RA, age, and anti-cyclic citrullinated peptide antibody. CONCLUSION: TCZ decreased the NT-proBNP level in patients with RA without preceding cardiovascular disease and CHF. TCZ may have a cardioprotective effect in those with active RA.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Insuficiencia Cardíaca/prevención & control , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Adulto , Anciano , Artritis Reumatoide/sangre , Artritis Reumatoide/complicaciones , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
10.
J Appl Microbiol ; 120(5): 1282-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26855315

RESUMEN

AIMS: This study aims to produce hydroxy fatty acids efficiently. METHODS AND RESULTS: Escherichia coli overexpressing linoleic acid Δ9 hydratase from Lactobacillus plantarum AKU 1009a was employed to produce hydroxy fatty acids with industrial potential. We found that 280 g l(-1) of linoleic acid (1 mol l(-1)) was converted into (S)-10-hydoxy-cis-12-octadecenoic acid (HYA) with a high conversion rate of 98% (mol/mol) and more than 99·9% enantiomeric excess (e.e.) by recombinant E. coli cells in the presence of FAD and NADH. In the same way, many kinds of C18 unsaturated fatty acids with Δ9 carbon double bond (280 g l(-1)) were converted into corresponding 10-hydroxy fatty acids with the conversion rates over 95% (mol/mol). We also produced HYA at a high rate of accumulation (289 g l(-1) ) with a high yield (97 mol%) in a reaction mixture that contained glucose instead of NADH. CONCLUSIONS: We developed a process for producing several types of hydroxy fatty acids with high accumulation rates and high yields. SIGNIFICANCE AND IMPACT OF THE STUDY: Hydroxy fatty acids are important materials for the chemical, food, cosmetic and pharmaceutical industries, and thus they have recently attracted much interest in a variety of research fields. However, the mass production of hydroxy fatty acids has been limited. This method of hydroxy fatty acids production will facilitate the widespread application of hydroxy fatty acids in various industries.


Asunto(s)
Ácidos Grasos/biosíntesis , Hidroxiácidos/metabolismo , Lactobacillus plantarum/enzimología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Lactobacillus plantarum/genética , Ácido Linoleico/metabolismo , Organismos Modificados Genéticamente/metabolismo
11.
Clin Exp Allergy ; 42(2): 315-25, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22092376

RESUMEN

BACKGROUND: The chemokine receptor CCR4 has been implicated in Th2 cell-mediated immune responses. However, other T cell subsets are also known to participate in allergic inflammation. OBJECTIVE: The role of CCR4 in Th1, Th2, and Th17 cell-mediated allergic airway inflammation was investigated. METHOD: We generated an allergic airway inflammation model by adoptive transfer of in vitro-polarized ovalbumin (OVA)-specific Th1, Th2, and Th17 cells. The effect of a low-molecular weight CCR4 antagonist, Compound 22, on this model was examined. RESULTS: Upon in vitro polarization of DO11.10 naïve T cells, Th1- and Th2-polarized cells dominantly expressed CXCR3 and CCR4, respectively, while Th17-polarized cells expressed CCR6 and CCR4. Intranasal OVA-challenge of mice transferred with each T cell subset induced accumulation of T cells in the lungs. Eosinophils were also massively accumulated in Th2-transferred mice, whereas neutrophils were preferentially recruited in Th1- and Th17-transferred mice. Compound 22, as well as anti-CCL17 or anti-CCL22 antibody selectively suppressed accumulation of Th2 cells and eosinophils in the lungs of Th2-transferred and OVA-challenged mice. Compound 22 also inhibited bronchial hyperresponsiveness but had little effect on goblet cell hyperplasia in Th2-transferred and OVA-challenged mice. CONCLUSIONS AND CLINICAL RELEVANCE: There were notable differences in allergic lung inflammation mediated by different T cell subsets. CCR4 blockage was selectively effective for suppression of Th2-mediated allergic inflammation by blocking infiltration of Th2 cells.


Asunto(s)
Regulación hacia Abajo/inmunología , Receptores CCR4/antagonistas & inhibidores , Hipersensibilidad Respiratoria/tratamiento farmacológico , Células Th2/inmunología , Traslado Adoptivo , Animales , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Células Caliciformes/inmunología , Células Caliciformes/patología , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/inmunología , Inflamación/patología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Receptores CCR4/genética , Receptores CCR4/inmunología , Receptores CCR6/antagonistas & inhibidores , Receptores CCR6/genética , Receptores CCR6/inmunología , Hipersensibilidad Respiratoria/genética , Hipersensibilidad Respiratoria/inmunología , Hipersensibilidad Respiratoria/patología , Células TH1/inmunología , Células TH1/patología , Células Th17/inmunología , Células Th17/patología , Células Th2/patología
12.
Nat Commun ; 13(1): 6259, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36307443

RESUMEN

Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA's Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations.

13.
J Cell Biol ; 117(4): 889-94, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1315783

RESUMEN

The addition of exogenous hepatocyte growth factor (HGF)/scatter factor (SF) to MDCK epithelial cells results in fibroblastic morphology and cell motility. We generated HGF/SF producing MDCK cells by transfection with an expression plasmid containing human HGF/SF cDNA. Production of HGF/SF by these cells induced a change from an epithelial to a fibroblastic morphology and increased cell motility. In addition, the HGF/SF producing cells acquired efficient anchorage-independent growth in soft agar but did not form tumors in nude mice. The morphological change and the stimulation of the anchorage-independent growth were prevented by anti-HGF/SF antibody, suggesting that the factor is secreted and then exerts its effects through cell surface receptors.


Asunto(s)
Células Epiteliales , Sustancias de Crecimiento/fisiología , Animales , División Celular , Movimiento Celular , Polaridad Celular , Células Cultivadas , Perros , Expresión Génica , Factor de Crecimiento de Hepatocito , Humanos , Técnicas Inmunológicas , Técnicas In Vitro , ARN Mensajero/genética , Receptores de Superficie Celular/fisiología , Transfección
14.
J Cell Biol ; 128(5): 949-57, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7876318

RESUMEN

p120 was originally identified as a substrate of pp60src and several receptor tyrosine kinases, but its function is not known. Recent studies revealed that this protein shows homology to a group of proteins, beta-catenin/Armadillo and plakoglobin (gamma-catenin), which are associated with the cell adhesion molecules cadherins. In this study, we examined whether p120 is associated with E-cadherin using the human carcinoma cell line HT29, as well as other cell lines, which express both of these proteins. When proteins that copurified with E-cadherin were analyzed, not only alpha-catenin, beta-catenin, and plakoglobin but also p120 were detected. Conversely, immunoprecipitates of p120 contained E-cadherin and all the catenins, although a large subpopulation of p120 was not associated with E-cadherin. Analysis of these immunoprecipitates suggests that 20% or less of the extractable E-cadherin is associated with p120. When p120 immunoprecipitation was performed with cell lysates depleted of E-cadherin, beta-catenin was no longer coprecipitated, and the amount of plakoglobin copurified was greatly reduced. This finding suggests that there are various forms of p120 complexes, including p120/E-cadherin/beta-catenin and p120/E-cadherin/plakoglobin complexes; this association profile contrasts with the mutually exclusive association of beta-catenin and plakoglobin with cadherins. When the COOH-terminal catenin binding site was truncated from E-cadherin, not only beta-catenin but also p120 did not coprecipitate with this mutated E-cadherin. Immunocytological studies showed that p120 colocalized with E-cadherin at cell-cell contact sites, even after non-ionic detergent extraction. Treatment of cells with hepatocyte growth factor/scatter factor altered the level of tyrosine phosphorylation of p120 as well as of beta-catenin and plakoglobin. These results suggest that p120 associates with E-cadherin at its COOH-terminal region, but the mechanism for this association differs from that for the association of beta-catenin and plakoglobin with E-cadherin, and thus, that p120, whose function could be modulated by growth factors, may play a unique role in regulation of the cadherin-catenin adhesion system.


Asunto(s)
Cadherinas/metabolismo , Moléculas de Adhesión Celular/metabolismo , Proteínas del Citoesqueleto/metabolismo , Fosfoproteínas/metabolismo , Transactivadores , Sitios de Unión , Cadherinas/aislamiento & purificación , Cateninas , Moléculas de Adhesión Celular/aislamiento & purificación , Compartimento Celular , Células Cultivadas , Detergentes , Técnica del Anticuerpo Fluorescente , Humanos , Fosfoproteínas/aislamiento & purificación , Fosforilación , Pruebas de Precipitina , Unión Proteica , Células Tumorales Cultivadas , Tirosina/metabolismo , beta Catenina , Catenina delta
15.
J Int Med Res ; 37(3): 892-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19589275

RESUMEN

Although the effects of angiotensin II receptor blockers (ARBs) on non-diabetic glomerulonephritis have been reported, studies of their effects on collagen-vascular diseases, particularly lupus nephritis, are limited. In this retrospective, observational study, systemic lupus erythematosus (SLE) patients (n = 7) with lupus nephritis and uncontrolled proteinuria were treated with an angiotensin-converting enzyme inhibitor followed by the ARB losartan (25 - 50 mg/day). Urinary protein excretion and renal function were evaluated. After 12 months of losartan, mean urinary protein excretion decreased significantly by 84.8%. Mean systolic and diastolic blood pressures also decreased significantly during the 12 months of losartan treatment, although not in normotensive patients. Complement 4, total complement activity and anti-dsDNA antibody levels, which are indices of SLE activity, and serum creatinine levels, which is an index of renal function, showed no change in response to losartan treatment. A more extensive evaluation of the effects of ARBs in patients with lupus nephritis and poorly controlled proteinuria is required.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Nefritis Lúpica/tratamiento farmacológico , Proteinuria/tratamiento farmacológico , Adolescente , Adulto , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Anticuerpos Antinucleares/metabolismo , Presión Sanguínea/efectos de los fármacos , Proteínas del Sistema Complemento/inmunología , Creatinina/sangre , Femenino , Humanos , Losartán/farmacología , Losartán/uso terapéutico , Nefritis Lúpica/sangre , Nefritis Lúpica/inmunología , Persona de Mediana Edad
16.
Methods Inf Med ; 47(6): 522-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19057809

RESUMEN

OBJECTIVES: Simultaneous dealing of hundreds of thousands of single nucleotide polymorphisms (SNPs) in genome-wide association studies is laborious. The aim of our study is to develop a method to decrease the number of candidate SNPs prior to the genotyping of study subjects. METHODS: We created virtual genotype data on case and control subjects from data of the International HapMap Project by using haplotype-based simulation method. We repeated virtual case-control association studies and selected candidate SNPs. We applied the selected SNPs to previously published genetic case-control studies. Sensitivity to detect association with causative genes using our method was compared to the original studies and results using tag SNPs. RESULTS: We found a discrete distribution pattern of SNPs, which was able to produce significant results in case-control association studies. The number of candidate SNPs that we selected was 24.7% of the number of the original set of SNPs. We applied this method to previously published genetic case-control studies and found that the use of candidate SNPs improved the sensitivity for detecting significant alleles, both compared to the original studies and to the use of tag SNPs. The results were not affected by the difference of the diseases and genes involved. CONCLUSIONS: Our simulation-based approach has advantages of reducing costs and improving performance to detect significant alleles. This method can be used without considering the specific disease and genes involved.


Asunto(s)
Genoma Humano , Genotipo , Haplotipos , Polimorfismo de Nucleótido Simple , Interfaz Usuario-Computador , Alelos , Estudios de Casos y Controles , Recolección de Datos , Humanos , Proyectos Piloto , Desarrollo de Programa , Factores de Tiempo
17.
Int J Oral Maxillofac Surg ; 37(4): 328-33, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18272336

RESUMEN

The aim of this study was to determine the effects of mandibular setback surgery on craniofacial and pharyngeal morphology and on respiratory function during sleep. The subjects were 17 patients in whom skeletal class III malocclusions were corrected by bilateral sagittal split ramus osteotomy. Arterial oxygen saturation (SpO2) during sleep was measured by pulse oximetry, and morphological changes were studied using cephalograms. The mean posterior movement of the mandible at surgery was 8.6mm at the pogonion, and many morphological and functional changes occurred with mandibular setback. Although there was no significant change at the oropharyngeal airway, significant protrusive head position and inferior displacement of the hyoid bone were seen postoperatively. Decreased SpO2 during sleep was found just after surgery, but had improved 1 month after surgery. It seems that almost all of the subjects adapted to the new environment in respiratory function during sleep, but patients with obesity, potential sleep-disordered breathing and a large amount of setback may suffer from obstructive sleep apnea (OSA) in the future. Careful postoperative follow up is needed for patients who have undergone mandibular setback surgery, and a strategy to prevent obstructive sleep apnea after mandibular setback surgery is needed.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Procedimientos Quirúrgicos Orales , Orofaringe/anatomía & histología , Adolescente , Adulto , Análisis de Varianza , Cefalometría , Femenino , Humanos , Masculino , Procedimientos Quirúrgicos Orales/efectos adversos , Osteotomía/efectos adversos , Oxígeno/sangre , Apnea Obstructiva del Sueño/etiología , Apnea Obstructiva del Sueño/prevención & control , Estadísticas no Paramétricas
18.
Br J Oral Maxillofac Surg ; 56(4): 340-342, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29599050

RESUMEN

Cholesterol crystals embolise when an aortic atherosclerotic lesion ruptures and cholesterol crystals are scattered and obstruct small peripheral arterioles. Risk factors include both iatrogenic factors such as intravascular catheterisation, and spontaneous factors for atherosclerosis such as aging, hypertension, dyslipidaemia, and smoking. We describe the case of an 83-year-old Japanese man who developed unilateral, superficial necrosis of the tongue as a result of spontaneous embolisation of cholesterol crystals.


Asunto(s)
Embolia por Colesterol/complicaciones , Enfermedades de la Lengua/etiología , Anciano de 80 o más Años , Embolia por Colesterol/diagnóstico , Embolia por Colesterol/patología , Humanos , Masculino , Necrosis , Lengua/irrigación sanguínea , Lengua/patología , Enfermedades de la Lengua/diagnóstico , Enfermedades de la Lengua/patología
19.
Science ; 361(6406): 1000-1003, 2018 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-30190400

RESUMEN

Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth's magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He+ to energies up to ~2 kilo-electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.

20.
J Clin Invest ; 87(5): 1853-7, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1827130

RESUMEN

Human hepatocyte growth factor (hHGF) has recently been expressed as a recombinant polypeptide from Chinese hampster ovary cell transfectants. Using a primary rat hepatocyte bioassay, we have tested the biological activity of recombinant hHGF and compared it with native hHGF. Dose-response curves were almost identical, with half-maximal stimulation of DNA synthesis at 1-2 ng/ml (equivalent to approximately 10 pM). S-phase labeling index was similarly enhanced and numerous mitotic cells were observed. Recombinant and native hHGF also stimulated DNA synthesis and S-phase labeling index in primary adult human hepatocytes. Human cells were more responsive than rat hepatocytes, with recombinant hHGF slightly more potent than native hHGF (half-maximal stimulation 0.3 and 0.6 ng/ml, respectively). Since HGF levels rise in patients with fulminant hepatic failure and in animals after partial hepatectomy or administration of hepatotoxins, situations where liver regeneration occurs, HGF is suggested to play a key role in regulation of hepatic growth. The high potency of the factor on human hepatocytes reinforces its candidacy as a critical mitogen in human liver growth. The availability of a recombinant hHGF opens the way for in vivo experimental studies and to the possibility of using hHGF as a clinical therapeutic agent, either alone or in combination with other factors.


Asunto(s)
ADN/biosíntesis , Sustancias de Crecimiento/farmacología , Hígado/efectos de los fármacos , Adulto , Animales , Relación Dosis-Respuesta a Droga , Sustancias de Crecimiento/análisis , Factor de Crecimiento de Hepatocito , Humanos , Hígado/metabolismo , Masculino , Ratas , Ratas Endogámicas , Proteínas Recombinantes/farmacología
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