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1.
Phys Rev Lett ; 130(13): 132502, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37067317

RESUMEN

The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.

2.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37172243

RESUMEN

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

3.
Phys Rev Lett ; 128(11): 112503, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35363014

RESUMEN

We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst) eV and 6463.7±0.3(stat)±0.1(syst) eV, and widths to be 2.5±1.0(stat)±0.4(syst) eV and 1.0±0.6(stat)±0.3(stat) eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

4.
Phys Rev Lett ; 126(6): 062501, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33635678

RESUMEN

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21 MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

5.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34397250

RESUMEN

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

6.
J Eur Acad Dermatol Venereol ; 35(9): 1765-1776, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33960033

RESUMEN

Frequently described as 'the worst itch' one can ever experience scabies itch is the hallmark of Sarcoptes scabiei mite infestation. Notably, the itchiness often persists for weeks despite scabicides therapy. The mechanism of scabies itch is not yet fully understood, and effective treatment modalities are still missing which can severely affect the quality of life. The aim of this review is to provide an overview of the scope of itch in scabies and highlight candidate mechanisms underlying this itch. We herein discuss scabies itch, with a focus on the nature, candidate underlying mechanisms and treatment options. We also synthesize this information with current understanding of the mechanisms contributing to non-histaminergic itch in other conditions. Itch is a major problem in scabies and can lead to grave consequences. We provide the latest insights on host-mite interaction, secondary microbial infection and neural sensitization with special emphasis on keratinocytes and mast cells to better understand the mechanism of itch in scabies. Also, the most relevant current modalities remaining under investigation that possess promising perspectives for scabies itch (i.e. protease-activated receptor-2 (PAR-2) inhibitor, Mas-related G protein-coupled receptor X2 (MRGPRX2) antagonist) are discussed. Greater understanding of these diverse mechanisms may provide a rational basis for the development of improved and targeted approaches to control itch in individuals with scabies.


Asunto(s)
Escabiosis , Animales , Humanos , Proteínas del Tejido Nervioso , Neuroinmunomodulación , Prurito/tratamiento farmacológico , Prurito/etiología , Calidad de Vida , Receptores Acoplados a Proteínas G , Receptores de Neuropéptido , Sarcoptes scabiei , Escabiosis/complicaciones , Escabiosis/tratamiento farmacológico
7.
Phys Rev Lett ; 125(19): 192505, 2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33216598

RESUMEN

Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed a T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced E2 hindrance factor f_{ν}=27±1 supports the interpretation that axial symmetry is approximately conserved.

8.
Phys Rev Lett ; 124(20): 202501, 2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32501086

RESUMEN

We measured missing mass spectrum of the ^{12}C(γ,p) reaction for the first time in coincidence with potential decay products from η^{'} bound nuclei. We tagged an (η+p) pair associated with the η^{'}N→ηN process in a nucleus. After applying kinematical selections to reduce backgrounds, no signal events were observed in the bound-state region. An upper limit of the signal cross section in the opening angle cosθ_{lab}^{ηp}<-0.9 was obtained to be 2.2 nb/sr at the 90% confidence level. It is compared with theoretical cross sections, whose normalization ambiguity is suppressed by measuring a quasifree η^{'} production rate. Our results indicate a small branching fraction of the η^{'}N→ηN process and/or a shallow η^{'}-nucleus potential.

9.
Nature ; 510(7504): 247-9, 2014 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-24919918

RESUMEN

Long-duration γ-ray bursts are associated with the explosions of massive stars and are accordingly expected to reside in star-forming regions with molecular gas (the fuel for star formation). Previous searches for carbon monoxide (CO), a tracer of molecular gas, in burst host galaxies did not detect any emission. Molecules have been detected as absorption in the spectra of γ-ray burst afterglows, and the molecular gas is similar to the translucent or diffuse molecular clouds of the Milky Way. Absorption lines probe the interstellar medium only along the line of sight, so it is not clear whether the molecular gas represents the general properties of the regions where the bursts occur. Here we report spatially resolved observations of CO line emission and millimetre-wavelength continuum emission in two galaxies hosting γ-ray bursts. The bursts happened in regions rich in dust, but not particularly rich in molecular gas. The ratio of molecular gas to dust (<9-14) is significantly lower than in star-forming regions of the Milky Way and nearby star-forming galaxies, suggesting that much of the dense gas where stars form has been dissipated by other massive stars.

10.
Br J Dermatol ; 180(1): 187-192, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29573413

RESUMEN

We report a unique case of a Japanese woman with herpetiform pemphigus (HP) who had IgG autoantibodies reactive with nondesmosomal sites of keratinocytes and presented characteristic transmission electron microscopic (TEM) findings of various-sized vacuoles in keratinocytes without acantholysis. The patient presented with pruritic annular oedematous erythemas with small blisters lining the margins on the trunk and extremities. Histopathological examinations showed intraepidermal blisters with prominent infiltrations of eosinophils. Direct and indirect immunofluorescence tests revealed the presence of in vivo bound and circulating IgG autoantibodies to the keratinocyte cell surfaces. However, enzyme-linked immunosorbent assays for desmoglein (Dsg) 1, Dsg3 and desmocollins 1-3 showed negative results. Immunoblotting using the full-length human Dsg1 recombinant protein showed a positive band. TEM examination showed various-sized vacuoles squashing the nuclei in many keratinocytes, resulting in rupture of the cells. Immunoelectron microscopic examination revealed IgG deposition over the entire keratinocyte cell surfaces, which spared the desmosomes. IgG antibodies were also present on the inside walls of the vacuoles around the nuclei of keratinocytes and on the cell surfaces of infiltrating eosinophils. This patient also had marked eosinophilia and high levels of thymus and activation-regulated chemokine and interleukin-5 in the serum. These results indicated a novel autoantigen on the nondesmosomal keratinocyte cell surfaces and the pathogenesis of bullous spongiotic change with inflammation in HP.


Asunto(s)
Dermatitis Herpetiforme/diagnóstico , Queratinocitos/ultraestructura , Pénfigo/diagnóstico , Piel/patología , Anciano , Dermatitis Herpetiforme/patología , Desmosomas/ultraestructura , Femenino , Humanos , Queratinocitos/citología , Microscopía Electrónica de Transmisión , Pénfigo/patología , Piel/citología , Vacuolas/ultraestructura
11.
Br J Dermatol ; 180(1): 149-156, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30216412

RESUMEN

BACKGROUND: Antilaminin 332 mucous membrane pemphigoid (MMP) is an autoimmune subepidermal blistering disease with predominant mucosal involvement and autoantibodies against laminin 332. Malignancies have been associated with this disease; however, no standardized detection system for antilaminin 332 serum antibodies is widely available. OBJECTIVES: Development of a sensitive and specific assay for the detection of antilaminin 332 antibodies. METHODS: An indirect immunofluorescence (IF) assay using recombinant laminin 332 was developed and probed with a large number of antilaminin 332 MMP patient sera (n = 93), as well as sera from patients with antilaminin 332-negative MMP (n = 153), bullous pemphigoid (n = 20), pemphigus vulgaris (n = 20) and noninflammatory dermatoses (n = 22), and healthy blood donors (n = 100). RESULTS: In the novel IF assay, sensitivities with the laminin 332 heterotrimer and the individual α3, ß3 and γ2 chains were 77%, 43%, 41% and 13%, respectively, with specificities of 100% for each substrate. The sensitivity for the heterotrimer increased when an anti-IgG4 enriched antitotal IgG conjugate was applied. Antilaminin 332 reactivity paralleled disease activity and was associated with malignancies in 25% of patients with antilaminin 332 MMP. CONCLUSIONS: The novel IF-based assay will facilitate the serological diagnosis of antilaminin 332 MMP and may help to identify patients at risk of a malignancy.


Asunto(s)
Autoanticuerpos/sangre , Autoantígenos/inmunología , Moléculas de Adhesión Celular/inmunología , Penfigoide Benigno de la Membrana Mucosa/diagnóstico , Autoanticuerpos/inmunología , Estudios de Cohortes , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Penfigoide Benigno de la Membrana Mucosa/sangre , Proteínas Recombinantes/inmunología , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Kalinina
12.
J Eur Acad Dermatol Venereol ; 33(4): 735-741, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29972879

RESUMEN

BACKGROUND: Anti-laminin-γ1 (lam-γ1) pemphigoid, a recently described immunobullous disorder sharing immune serological features of bullous pemphigoid and epidermolysis bullosa acquisita (EBA), is characterized by the detection of serum IgG autoantibodies against the lam-γ1 chain, a 200 kDa heterotrimeric component of the dermal-epidermal junction (DEJ). OBJECTIVE: The aim of the study was to develop an easy-to-perform and reliable assay for the serological detection of anti-lam-γ1 IgG autoantibodies. The clinical appearance alone is not sufficient to establish diagnosis of anti-lam-γ1 pemphigoid and rather requires immune serological evidence of (i) IgG reactivity against the dermal portion of salt-split human skin; (ii) exclusion of IgG against other components of the DEJ; and (iii) IgG reactivity with a 200 kDa protein of dermal extracts by immunoblot analysis (IB). METHODS: The sera of 55 patients with anti-lam-γ1 pemphigoid were tested by IB with two recombinant heterotrimers, laminin 111 (lam-111) and laminin 421 (lam-421), as well as with a recombinant lam-γ1 chain monomer. Additionally, a total of 41 control sera from patients with EBA (n = 15), psoriasis vulgaris (PV; n = 14), and healthy controls (HC; n = 12) were tested. RESULTS: Immunoblot analysis revealed a positive reactivity with lam-111 and/or lam-421 in 46/55 (84%) of anti-lam-γ1 pemphigoid sera. Moreover, 8/9 of the initially non-reactive sera were positive with the lam-γ1 monomer, leading to an overall sensitivity of 98.2%. Analyses of 41 control sera with the three lam-γ1 recombinants led to a specificity of 88%. Specifically, 3/15 EBA sera, 1/14 PV serum and 1/12 HC serum reacted with the lam-γ1 monomer while only the 3 EBA sera reacted with lam-421. CONCLUSIONS: Here we show a novel two-step IB assay using the two recombinant laminin trimers and lam-γ1 chain monomer for the detection of anti-lam-γ1 serum IgG with high sensitivity and specificity. This assay will facilitate the diagnosis and further characterization of this disease.


Asunto(s)
Autoanticuerpos/sangre , Inmunoglobulina G/sangre , Laminina/inmunología , Penfigoide Ampolloso/diagnóstico , Penfigoide Ampolloso/inmunología , Dermatitis por Contacto , Femenino , Humanos , Immunoblotting/métodos , Masculino , Persona de Mediana Edad , Penfigoide Ampolloso/sangre , Proteínas Recombinantes , Pruebas Serológicas
13.
J Eur Acad Dermatol Venereol ; 33(12): 2327-2333, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31325388

RESUMEN

BACKGROUND: The BIOCHIP (Dermatology Mosaic 7; EUROIMMUN, Lubeck, Germany) is a novel multiplex indirect immunofluorescence (IIF) technique used in the serological diagnosis of bullous pemphigoid (BP) and pemphigus. OBJECTIVE: To validate the accuracy and inter-rater reliability (IRR) of the BIOCHIP in the diagnosis of BP, pemphigus foliaceus (PF) and pemphigus vulgaris (PV). METHODS: Sera from patients with BP (n = 38), PF (n = 8), PV (n = 23), control patients (n = 64) and healthy control volunteers (n = 39) were tested. Sera were collected and analysed during the course of the disease at 1-5 different time points. The BIOCHIP was performed for all patients, digital images were captured of each incubated field, and the images were shared with 10 dermatologists experienced in reading IF from around the world to report. There were 312 BIOCHIP slides consisting of 1872 photos in total. All patients were de-identified. Fleiss Kappa was used to estimate the IRR. RESULTS: Fleiss Kappa was computed for each category (Oesophagus, Oesophagus immunofluorescence pattern, Salt-Split Skin (SSS), SSS immunofluorescence location, BP180, BP230, Dsg 1 and Ds3). The inter-rater agreement between the 10 raters varied between fair and moderate for all categories. Those that demonstrated fair concordance included monkey oesophagus (k = 0.257, P < 0.0001), oesophagus pattern (k = 0.357, P < 0.0001), Dsg1 (k = 0.390, P < 0.0001) and BP230 (k = 0.281, P < 0.0001). Moderate agreement was demonstrated for SSS (k = 0.416, P < 0.0001), SSS immunofluorescence location (k = 0.505, P < 0.0001), Dsg3 (k = 0.437, P < 0.0001) and BP180 (k = 0.559, P < 0.0001). CONCLUSION: The BIOCHIP mosaic-based immunofluorescence test is a simple, time and effort saving test that can aid in the diagnosis and screening of BP, PV and PF. However, the level of agreement was relatively low. The authors found the most common causes to be variable levels of training, indicating the presence of a learning curve in the interpretation of the results and ambiguous staining patterns leading to incongruent results.


Asunto(s)
Técnica del Anticuerpo Fluorescente/métodos , Variaciones Dependientes del Observador , Penfigoide Ampolloso/diagnóstico , Estudios de Casos y Controles , Humanos
14.
Hell J Nucl Med ; 22 Suppl 2: 141, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31802054

RESUMEN

INTRODUCTION: Magnetic resonance imaging (MRI) is a tomography technology that enables the depiction of anatomical structures with information about various features. Compressed sensing (CS) technology has recently been used for magnetic resonance image reconstruction from sparse information. Random sampling methods based on the various probability density function (PDF) are being developed to allow the efficient application of CS technology. Accurate numerical simulation is obviously important for the evaluation of the sampling method that are developed. In this study, the simulation method with MRI simulator and actual MRI scanner was carried out. Moreover, the difference between the result acquired from our simulation and basic one was revealed. METHODS: We first examined a basic method using a 2D Shepp-Logan phantom. This method was only conducted with k-space data obtained from the 2D Fourier transform of the original image. Our method of numerical simulation was applied with the MRI simulator (Bloch Solver, MRI simulations Inc.), an actual MRI system (Vantage Titan 3T, Canon Medical Systems) and a phantom (CAGN-3.0T phantom, Kato Medience). The real and imaginary part of the k-space were acquired with the MRI simulator using a phase map that was imaged by the actual MRI scanner. Random sampling was performed with two types of PDF and image reconstruction was processed by projection onto convex sets (POCS). Hermitian symmetry is a point-symmetry respect to origin and each point located on the opposite side maintains a relation of complex conjugate. Thus, there is no need to acquire data that formed in point-symmetry with the data that had already been acquired. We used the gaussian random sampling method (GA) and a method that considered Hermitian symmetry (GH). The image quality was evaluated using the normalized root mean squared error (NRMSE). RESULTS AND DISCUSSION: In the basic simulation, the average and standard deviation of NRMSE from GH was better than that from GA because consideration of the Hermitian symmetry enables the efficient acquisition of data. However, in our method of numerical simulation, the average and standard deviation of the NRMSE from GH was worse than that from GA. In this simulation method, the phase error was included in the real and imaginary part of the k-space; thus, the Hermitian symmetry cannot hold and the calculation error of reconstruction images from GH stood out. CONCLUSION: The method of numerical simulation with the MRI simulator using a phase map was close to the actual conditions and was considered to be useful for the validation of new sampling methods. The random sampling method using GH is expected to be useful for the highly efficient acquisition of data under ideal conditions; however, more accurate phase correction is necessary to apply the actual measurement data.


Asunto(s)
Compresión de Datos/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Algoritmos , Simulación por Computador , Análisis de Fourier , Modelos Teóricos , Distribución Normal , Fantasmas de Imagen
15.
Eur J Clin Microbiol Infect Dis ; 37(1): 91-98, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28920166

RESUMEN

Chronic pulmonary aspergillosis (CPA) is associated with mortality in patients with Mycobacterium avium complex lung disease (MAC-LD). An Aspergillus-positive respiratory specimen often reflects colonization, and thus the clinical significance of Aspergillus isolation in MAC-LD patients is not well understood. The objective of this study was to investigate the clinical characteristics and outcomes of MAC-LD patients in whom Aspergillus was isolated from respiratory specimens. We performed a retrospective review of the medical records of 329 MAC-LD patients. We compared the characteristics and mortality rates between patients with Aspergillus isolation and those without. All Aspergillus species detected from respiratory specimens within the follow-up period were reviewed. Aspergillus was detected in 40 (12.2%) of the 329 patients. There were no significant differences in the clinical characteristics and mortality rates between patients with and without Aspergillus isolation. Among the 40 patients with Aspergillus isolation, 9 (22.5%) developed CPA. CPA was most often caused by A. fumigatus. In the 40 Aspergillus-positive patients, patients with A. fumigatus isolation had a significantly higher mortality rate than those without (P < 0.001). The multivariate Cox proportional hazards model showed older age (P = 0.050), presence of respiratory comorbidities (P = 0.008), hypoalbuminemia (P < 0.001), and isolation of A. fumigatus (P = 0.005) to be prognostic factors for mortality in MAC-LD patients. There was no significant difference in the mortality rates between patients with Aspergillus isolation and those without. However, isolation of A. fumigatus may be associated with poor prognosis in MAC-LD patients.


Asunto(s)
Aspergillus fumigatus/aislamiento & purificación , Enfermedades Pulmonares/microbiología , Complejo Mycobacterium avium/aislamiento & purificación , Infección por Mycobacterium avium-intracellulare/mortalidad , Aspergilosis Pulmonar/mortalidad , Anciano , Femenino , Humanos , Hipoalbuminemia/complicaciones , Masculino , Infección por Mycobacterium avium-intracellulare/complicaciones , Pronóstico , Modelos de Riesgos Proporcionales , Aspergilosis Pulmonar/complicaciones , Estudios Retrospectivos
16.
Clin Exp Dermatol ; 43(8): 917-920, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29862541

RESUMEN

Pemphigus vegetans (PVeg) is a rare variant of pemphigus, characterized by vegetating lesions mainly with antidesmoglein 3 antibodies. However, the pathomechanisms for PVeg is still unknown. We present a patient with PVeg mainly associated with antidesmocollin (Dsc)3 antibodies, who originally developed pemphigus foliaceus. Serum levels of eosinophil cationic protein and transforming growth factor (TGF)-α increased at the onset of PVeg in this patient. Thus, TGF-α might be involved in the formation of vegetating lesions in PVeg.


Asunto(s)
Autoanticuerpos/sangre , Desmogleína 3/inmunología , Proteína Catiónica del Eosinófilo/sangre , Pénfigo/sangre , Factor de Crecimiento Transformador alfa/sangre , Humanos , Masculino , Persona de Mediana Edad , Pénfigo/patología , Piel/patología
17.
J Clin Pharm Ther ; 43(4): 571-573, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29265387

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Dravet syndrome (DS) is an intractable epilepsy syndrome. The three-drug combination therapy of sodium valproate (VPA), clobazam (CLB) and stiripentol (STP) is recommended worldwide. CASE SUMMARY: We present a case of DS, in which treatment with CLB could not be continued because of the appearance of adverse reactions to it. Replacement with topiramate (TPM) proved to be markedly effective. WHAT IS NEW AND CONCLUSION: It is suggested that combination therapy with VPA, TPM and STP is for DS epilepsy.


Asunto(s)
Anticonvulsivantes/efectos adversos , Anticonvulsivantes/uso terapéutico , Epilepsias Mioclónicas/tratamiento farmacológico , Preescolar , Dioxolanos/efectos adversos , Dioxolanos/uso terapéutico , Quimioterapia Combinada/métodos , Epilepsia/tratamiento farmacológico , Femenino , Fructosa/efectos adversos , Fructosa/análogos & derivados , Fructosa/uso terapéutico , Humanos , Topiramato , Ácido Valproico/efectos adversos , Ácido Valproico/uso terapéutico
18.
Cryo Letters ; 39(4): 251-254, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30963170

RESUMEN

BACKGROUND: DMSO and EG have been used as cryoprotectants for human ovarian tissue cryopreservation, but residual cryoprotectants concentration and safety have rarely been reported. OBJECTIVE: We aimed to compare residual cryoprotectants (DMSO, EG) concentration in bovine ovarian tissue during warming steps between one kind of common slow freezing method and two kinds of vitrification methods, which are usually used for cryopreservation of human ovarian tissue in Japan. MATERIALS AND METHODS: In this study, we used five bovine ovaries with an average age of 24.2 months divided into three kinds of cryopreservation methods. All ovarian cortices cut to 1 mm thickness were cryopreserved in slow freezing and two kinds of vitrification methods. Residual cryoprotectants before, during and after warming of cryopreserved ovarian cortices were measured using GC-MS and compared. RESULTS: Concentrations of residual cryoprotectants in the ovarian tissue just before transplantation into the body after warming were high after both vitrification methods but almost zero with the slow freezing method. CONCLUSION: We are concerned about the residual cryoprotectants in ovarian tissue, and continue to study the safety of cryopreservation methods to the woman after reimplantation and her baby.


Asunto(s)
Crioprotectores/química , Dimetilsulfóxido/química , Glicol de Etileno/química , Congelación , Ovario/química , Vitrificación , Animales , Bovinos , Criopreservación , Femenino
19.
Phys Rev Lett ; 119(18): 182503, 2017 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-29219585

RESUMEN

The gamma strength function and level density of 1^{-} states in ^{96}Mo have been extracted from a high-resolution study of the (p[over →], p[over →]^{'}) reaction at 295 MeV and extreme forward angles. By comparison with compound nucleus γ decay experiments, this allows a test of the generalized Brink-Axel hypothesis in the energy region of the pygmy dipole resonance. The Brink-Axel hypothesis is commonly assumed in astrophysical reaction network calculations and states that the gamma strength function in nuclei is independent of the structure of the initial and final state. The present results validate the Brink-Axel hypothesis for ^{96}Mo and provide independent confirmation of the methods used to separate gamma strength function and level density in γ decay experiments.

20.
Phys Rev Lett ; 118(5): 052701, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28211732

RESUMEN

The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.

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