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1.
Sci Rep ; 14(1): 2573, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336981

RESUMEN

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 Prev Alzheimers Dis ; 11(1): 138-148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38230726

RESUMEN

BACKGROUND: Epidemiological evidence has demonstrated a clear association between diabetes mellitus and increased risk of Alzheimer's disease (AD). Cerebral accumulation of phosphorylated tau aggregates, a cardinal neuropathological feature of AD, is associated with neurodegeneration and cognitive decline. Clinical and experimental studies indicate that diabetes mellitus affects the development of tau pathology; however, the underlying molecular mechanisms remain unknown. OBJECTIVE: In the present study, we used a unique diabetic AD mouse model to investigate the changes in tau phosphorylation patterns occurring in the diabetic brain. DESIGN: Tau-transgenic mice were fed a high-fat diet (n = 24) to model diabetes mellitus. These mice developed prominent obesity, severe insulin resistance, and mild hyperglycemia, which led to early-onset neurodegeneration and behavioral impairment associated with the accumulation of hyperphosphorylated tau aggregates. RESULTS: Comprehensive phosphoproteomic analysis revealed a unique tau phosphorylation signature in the brains of mice with diabetic AD. Bioinformatic analysis of the phosphoproteomics data revealed putative tau-related kinases and cell signaling pathways involved in the interaction between diabetes mellitus and AD. CONCLUSION: These findings offer potential novel targets that can be used to develop tau-based therapies and biomarkers for use in AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Diabetes Mellitus Tipo 2 , Ratones , Humanos , Animales , Enfermedad de Alzheimer/metabolismo , Proteínas tau/metabolismo , Fosforilación , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Ratones Transgénicos , Disfunción Cognitiva/complicaciones
3.
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.

4.
Med. infant ; 29(1): 23-29, Marzo 2022. Tab
Artículo en Español | LILACS | ID: biblio-1366940

RESUMEN

Introducción: existen dos rutas para realizar el reemplazo de esófago (RE), la retroesternal (RRE) y la mediastinal posterior (RMP). El objetivo del estudio es comparar los pacientes que recibieron un ascenso gástrico parcial empleando estas dos rutas. Material y métodos: Se revisaron las historias clínicas de 51 pacientes con ascenso gástrico parcial, en 27 años en el Hospital Garrahan. Se utilizó la vía RRE en 25 casos y la RMP en 26. Fueron comparados los datos epidemiológicos de los grupos y las variables para valorar la dificultad del acto quirúrgico, evolución inmediata y alejada. El estudio es comparativo, retro-prospectivo y longitudinal. Resultados: las características generales de los pacientes fueron similares. Los que recibieron el ascenso gástrico por vía RMP presentaron una menor incidencia de dehiscencia (p=0,017), de enfermedad por reflujo gastroesofágico (ERGE) (p=0,001) y de dumping (p=0,0001). No hubo diferencias estadísticamente significativas entre los dos grupos al comparar la duración del procedimiento, días de internación total y en Unidad de Cuidados Intensivos (UCI), días de permanencia en asistencia respiratoria mecánica (ARM), inicio de alimentación oral y estenosis de la anastomosis. Se observó una tendencia clínicamente relevante, que no alcanzó significancia estadística en las complicaciones intraquirúrgicas y número de dilataciones postoperatorias. No hubo necrosis del ascenso. Fallecieron 2 pacientes. Conclusiones: considerando la menor incidencia de dehiscencia, ERGE y dumping reemplazados por RMP, elegimos a ésta como nuestra primera opción para el reemplazo esofágico en la infancia (AU)


Introduction: The two routes for esophageal replacement (ER) are retrosternal (RRE) and posterior mediastinal (PMR). The aim of the study was to compare patients who received a partial gastric pull-up using either of these two routes. Material and methods: The clinical records of 51 patients who underwent partial gastric pull-up over 27 years at the Garrahan Hospital were reviewed. The RRE route was used in 25 and the RMP in 26 cases. The epidemiological data of the groups and the variables to evaluate the complexity of the surgical procedure, and shortand long-term outcome were compared. A comparative, retroprospective, and longitudinal study was conducted. Results: the general characteristics of the patients were similar. Those who underwent gastric pull-up via PMR had a lower incidence of dehiscence (p=0.017), gastroesophageal reflux disease (GERD) (p=0.001), and dumping (p=0.0001). No statistically significant differences were found between the two groups when comparing the duration of the procedure, days of total hospital and intensive care unit (ICU) stay, days on mechanical ventilation (MV), initiation of oral feeding and stenosis of the anastomosis. A clinically relevant trend, which did not reach statistical significance, was observed in intraoperative complications and number of postoperative dilatations. There was no necrosis of the pull-up. Two patients died. Conclusions: considering the lower incidence of dehiscence, GERD, and dumping associated with PMR, this was our first choice for esophageal replacement in infancy (AU)


Asunto(s)
Humanos , Lactante , Preescolar , Niño , Adolescente , Anastomosis Quirúrgica/métodos , Esofagectomía/métodos , Atresia Esofágica/cirugía , Atresia Esofágica/inducido químicamente , Esofagoplastia/métodos , Complicaciones Posoperatorias , Estudio Comparativo , Estudios Prospectivos , Estudios Retrospectivos , Estudios Longitudinales , Resultado del Tratamiento
5.
J Prev Alzheimers Dis ; 8(4): 465-476, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34585222

RESUMEN

BACKGROUND/OBJECTIVES: The Japan-multimodal intervention trial for prevention of dementia (J-MINT) is intended to verify the effectiveness of multi-domain interventions and to clarify the mechanism of cognitive improvement and deterioration by carrying out assessment of dementia-related biomarkers, omics analysis and brain imaging analysis among older adults at high risk of dementia. Moreover, the J-MINT trial collaborates with partnering private enterprises in the implementation of relevant interventional measures. This manuscript describes the study protocol. DESIGN/SETTING: Eighteen-month, multi-centered, randomized controlled trial. PARTICIPANTS: We plan to recruit 500 older adults aged 65-85 years with mild cognitive impairment. Subjects will be centrally randomized into intervention and control groups at a 1:1 allocation ratio using the dynamic allocation method with all subjects stratified by age, sex, and cognition. INTERVENTION: The multi-domain intervention program includes: (1) management of vascular risk factors; (2) group-based physical exercise and self-monitoring of physical activity; (3) nutritional counseling; and (4) cognitive training. Health-related information will be provided to the control group every two months. MEASUREMENTS: The primary and secondary outcomes will be assessed at baseline, 6-, 12-, and 18-month follow-up. The primary outcome is the change from baseline to 18 months in a global composite score combining several neuropsychological domains. Secondary outcomes include: cognitive change in each neuropsychological test, incident dementia, changes in blood and dementia-related biomarkers, changes in geriatric assessment including activities of daily living, frailty status and neuroimaging, and number of medications taken. CONCLUSIONS: This trial that enlist the support of private enterprises will lead to the creation of new services for dementia prevention as well as to verify the effectiveness of multi-domain interventions for dementia prevention.


Asunto(s)
Cognición/fisiología , Disfunción Cognitiva/terapia , Demencia/prevención & control , Ejercicio Físico , Evaluación Geriátrica , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Ejercicio Físico/fisiología , Femenino , Humanos , Japón , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Evaluación Nutricional , Factores de Riesgo
6.
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.

7.
Phys Rev Lett ; 124(25): 253201, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32639753

RESUMEN

We study an array of ultracold atoms in an optical lattice (Mott insulator) excited with a coherent ultrashort laser pulse to a state where single-electron wave functions spatially overlap. Beyond a threshold principal quantum number where Rydberg orbitals of neighboring lattice sites overlap with each other, the atoms efficiently undergo spontaneous Penning ionization resulting in a drastic change of ion-counting statistics, sharp increase of avalanche ionization, and the formation of an ultracold plasma. These observations signal the actual creation of electronic states with overlapping wave functions, which is further confirmed by a significant difference in ionization dynamics between a Bose-Einstein condensate and a Mott insulator. This system is a promising platform for simulating electronic many-body phenomena dominated by Coulomb interactions in the condensed phase.

8.
Br J Surg ; 107(6): 632-635, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32246473

RESUMEN

Probe electrospray ionization mass spectrometry (PESI-MS) is an ambient ionization-based mass spectrometry method that surpasses the original electrospray ionization technique in features such as the rapidity of analysis, simplicity of the equipment and procedure, and lower cost. This study found that the PESI-MS system with machine learning has the potential to establish a lipid-based diagnosis of breast cancer with higher accuracy, using a simpler approach. Rapid mass spectrometry for breast cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico , Mama/metabolismo , Metabolismo de los Lípidos , Espectrometría de Masa por Ionización de Electrospray , Biopsia , Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Sensibilidad y Especificidad
9.
Int J Oral Maxillofac Surg ; 49(4): 432-441, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31451304

RESUMEN

The objective was to introduce a new technique for visualizing the three-dimensional (3D) movements of velopharyngeal-related muscles using high-speed cine-magnetic resonance imaging (MRI) based on T2-weighted sequences. The evaluation of phonation- and water swallowing-related events was performed in 11 healthy subjects. Specifically, whether cine-MRI could precisely visualize normal velopharyngeal function during these two events was examined. The 3D movements of the soft palate, superior pharyngeal constrictor muscles, and levator veli palatini muscles were visualized in all 11 subjects. A noteworthy finding was that the magnetic resonance signals of the superior constrictor pharyngeal muscles and the levator veli palatini muscles were significantly higher during phonation and during water swallowing than at rest. This initial study suggests that the 3D movements of velopharyngeal-related muscles can be successfully and precisely visualized without side effects. The magnetic resonance signal changes seen in the superior pharyngeal constrictor and levator veli palatini muscles using the technique described here should be useful to develop better methods of evaluation of velopharyngeal function.


Asunto(s)
Insuficiencia Velofaríngea , Humanos , Imagen por Resonancia Magnética , Músculos Palatinos , Paladar Blando , Músculos Faríngeos
10.
Nat Mater ; 18(8): 811-815, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31209388

RESUMEN

Majorana quasiparticles in condensed matter are important for topological quantum computing1-3, but remain elusive. Vortex cores of topological superconductors may accommodate Majorana quasiparticles that appear as the Majorana bound state (MBS) at zero energy4,5. The iron-based superconductor Fe(Se,Te) possesses a superconducting topological surface state6-9 that was investigated by scanning tunnelling microscopy (STM) studies, which suggest such a zero-energy vortex bound state (ZVBS)10,11. Here we present ultrahigh energy-resolution spectroscopic imaging (SI)-STM to clarify the nature of the vortex bound states in Fe(Se,Te). We found the ZVBS at 0 ± 20 µeV, which constrained its MBS origin, and showed that some vortices host the ZVBS but others do not. We show that the fraction of vortices hosting the ZVBS decreases with increasing magnetic field and that local quenched disorders are not related to the ZVBS. Our observations elucidate the necessary conditions to realize the ZVBS, which paves the way towards controllable Majorana quasiparticles.

11.
Radiat Prot Dosimetry ; 183(1-2): 242-246, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30521045

RESUMEN

Uranium is renowned as a global contaminant, and attracts major concern with regards to the health risks involved because its nephrotoxicity. This paper discusses the development of a simple method to identify accumulated regions or localized sites of uranium within kidneys using the CR-39 plastic nuclear track detector. To demonstrate the proposed method, renal cryo-sections (5 µm-t) from Wistar male rats, subcutaneously administered with uranyl acetate (2 mg/kg), were prepared on day one after administration. Concerned sections were subsequently placed on CR-39, stored for 1.25 years, and then etched in a 7 M NaOH solution at 70°C for 3 h. α-tracks were then detected in the form of etch pits, corresponding to uranium, and also the tissue shape and structure were transferred as a roughness on the surface of CR-39. As observed, the proposed method served to facilitate simultaneous detection and identification of localized regions of uranium accumulation within kidneys.


Asunto(s)
Riñón/efectos de la radiación , Radiometría/métodos , Uranio/toxicidad , Animales , Masculino , Compuestos Organometálicos , Polietilenglicoles , Ratas , Ratas Wistar
12.
Int J Oral Maxillofac Surg ; 48(4): 480-487, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30316661

RESUMEN

The aim of this study was to determine whether the evaluation of neurovascular compression (NVC) using new criteria on magnetic resonance (MR) cisternography improves the prediction of the curative effects of carbamazepine (CBZ) in trigeminal neuralgia (TN). In this study, a new analysis of NVC using MR cisternography was performed retrospectively for 280 patients with clinical signs and symptoms suggesting TN. The new analysis examined whether the site of the NVC was less than 3mm from the edge of the exit point and within the first third of the root entry zone on MR cisternography. Prediction of the curative effects of CBZ using the new evaluation of distance to the NVC improved on the predictive ability of the previous method of calculating the NVC volume (Mantel-Haenszel coefficient, P<0.01). In particular, initial treatment with CBZ 100mg/day for 2 weeks appeared more effective for patients with NVC volumes of ≤5mm3 plus a distance to the NVC of ≤3mm, than for those with NVC volumes >5mm3. The evaluation of NVC on MR cisternography using this new approach appears to be more useful than the previous method for predicting the initial treatment response in patients with TN.


Asunto(s)
Neuralgia del Trigémino , Angiografía , Carbamazepina , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Estudios Retrospectivos
13.
Radiat Prot Dosimetry ; 183(1-2): 142-146, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30535060

RESUMEN

Bi-directional signaling involved in radiation-induced bystander effect (RIBE) between irradiated carcinoma cells and their surrounding non-irradiated normal cells is relevant to radiation cancer therapy. Using the SPICE-NIRS microbeam, we delivered 500 protons to A549-GFP lung carcinoma cells, stably expressing H2B-GFP, which were co-cultured with normal WI-38 cells. The level of γ-H2AX, a marker for DNA double-strand breaks (DSB), was subsequently measured up to 24-h post-irradiation in both targeted and bystander cells. As a result, inhibition of gap junction intercellular communication (GJIC) attenuated DSB repair in targeted A549-GFP cells, and suppressed RIBE in bystander WI-38 cells but not in distant A549-GFP cells. This suggests that GJIC plays a two-way role through propagating DNA damage effect between carcinoma to normal cells and reversing the bystander signaling, also called 'rescue effect' from bystander cells to irradiated cells, to enhance the DSB repair in targeted cells.


Asunto(s)
Células A549/efectos de la radiación , Comunicación Celular/efectos de la radiación , Roturas del ADN de Doble Cadena/efectos de la radiación , Uniones Comunicantes/efectos de la radiación , Neoplasias Pulmonares/radioterapia , Células Tumorales Cultivadas/efectos de la radiación , Efecto Espectador/efectos de la radiación , Células Cultivadas/efectos de la radiación , Técnicas de Cocultivo , Reparación del ADN , Fibroblastos/efectos de la radiación , Histonas/análisis , Humanos , Protones
14.
Hum Reprod ; 33(11): 1984-1991, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30299468

RESUMEN

STUDY QUESTION: What is the prevalence of multiple pregnancy with zygotic splitting after single embryo transfer (SET)? SUMMARY ANSWER: The prevalence of multiple pregnancy with zygotic splitting after SET was 1.36%. WHAT IS KNOWN ALREADY: In 2008, the Japan Society of Obstetrics and Gynaecology (JSOG) recommended the adoption of SET to reduce multiple births. Since then, to improve the clinical pregnancy rate, elective SET using blastocyst transfer and frozen-warmed ET has increased. Blastocyst culture and zona pellucida manipulation, including ICSI and AH, have been widely reported as risk factors for monozygotic twinning. However, all these studies may have included cases with dizygotic pregnancies produced by a transferred embryo and a spontaneous conception. STUDY DESIGN, SIZE, DURATION: A retrospective observational study was performed, based on 937 848 SET cycles in registered ART data from the JSOG between 2007 and 2014. The study was approved by the Registration and Research Subcommittee of the JSOG and Juntendo University Ethics Committee. PARTICIPANTS/MATERIALS, SETTING, METHODS: To identify possible factors affecting the prevalence of zygotic splitting, we identified pregnancies, in which the number of foetuses exceeded the number of gestational sacs (GSs), to restrict our analysis to 'true' zygotic splitting. Multiple logistic regression analysis was performed using singleton pregnancy after SET, as control. P < 0.05 was considered statistically significant. MAIN RESULTS AND THE ROLE OF CHANCE: Fresh and frozen-warmed SET produced 276 934 clinical pregnancies (29.5%/SET), including 4310 twins (1.56% of pregnancies) and 109 triplets (0.04% of pregnancies). Based on sex analysis of dichorionic twins after SET, the prevalence of multiple pregnancy with zygotic splitting was 1.36%. Statistical analysis revealed that compared to singleton pregnancies zygotic splitting pregnancies were associated with frozen-warmed ET cycles (odds ratio [OR] = 1.34; 95% CI: 1.16-1.55), blastocyst culture (OR = 1.79; 95% CI: 1.54-2.09) or AH (OR = 1.21; 95% CI: 1.08-1.35). In fresh ET cycles, the prevalence rate of zygotic splitting pregnancy after single blastocyst transfer was significantly higher than that after SET cycles with cleavage embryos (OR = 2.20; 95% CI: 1.83-2.66). However, no significant difference in ovarian stimulation and fertilization methods was recognized. LIMITATIONS, REASONS FOR CAUTION: In the current Japanese ART registry system, data regarding frozen-warmed ET do not include information about ovarian stimulation and fertilization methods. Registration for AH only began in 2010. There is no way of validating if data submitted by clinics is correct. WIDER IMPLICATIONS OF THE FINDINGS: Clinicians should consider whether to counsel couples about the small increase in the risk of zygotic splitting associated with some embryo manipulations. STUDY FUNDING/COMPETING INTEREST(S): No external funds were used for the study. The authors have no competing interests to declare. TRIAL REGISTRATION NUMBER: None.


Asunto(s)
Embarazo Múltiple/estadística & datos numéricos , Transferencia de un Solo Embrión/métodos , Gemelización Monocigótica/fisiología , Tasa de Natalidad , Técnicas de Cultivo de Embriones/métodos , Femenino , Fertilización In Vitro/métodos , Fertilización In Vitro/estadística & datos numéricos , Humanos , Japón , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Trillizos/estadística & datos numéricos , Gemelos/estadística & datos numéricos
15.
Scand J Rheumatol ; 47(5): 384-391, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29631459

RESUMEN

OBJECTIVE: Rheumatoid arthritis (RA) is a disease that typically induces secondary osteoporosis, which increases the risk of bone fractures. Anti-interleukin-6 (IL-6) receptor antibody is used to treat RA; however, its effect on bone strength is not clear. Therefore, we investigated the influence of MR16-1, an anti-mouse IL-6 receptor antibody, on bone structure and femoral strength in a collagen-induced arthritis (CIA) mouse model. METHOD: DBA/1J mice were immunized by intradermal injection of bovine type II collagen. MR16-1 was administered intraperitoneally at the same time as immunization. Thirty-five days after the first immunization, bone structure and bone strength were measured by micro-computed tomography and the three-point bending test. RESULTS: In the CIA group, most bone mineral density and bone structure parameters in the foot, femur, and lumbar spine were significantly lower than in the normal group. Moreover, the maximum load of the femoral shaft in the CIA group was significantly lower than in the normal group. MR16-1 treatment significantly prevented the CIA-induced deterioration of bone structure and loss of bone strength. CONCLUSION: These results suggest that CIA systemically induces a deterioration of bone structure and loss of bone strength, and that IL-6 signalling plays an important role in these processes.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Artritis Experimental/tratamiento farmacológico , Huesos/efectos de los fármacos , Osteoporosis/etiología , Receptores de Interleucina-6/antagonistas & inhibidores , Animales , Artritis Experimental/complicaciones , Densidad Ósea/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos DBA , Osteoporosis/tratamiento farmacológico , Microtomografía por Rayos X
16.
Osteoarthritis Cartilage ; 26(1): 108-117, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29074299

RESUMEN

OBJECTIVE: Chondrocyte differentiation is crucial for long bone growth. Many cartilage extracellular matrix (ECM) proteins reportedly contribute to chondrocyte differentiation, indicating that mechanisms underlying chondrocyte differentiation are likely more complex than previously appreciated. Angiopoietin-like protein 2 (ANGPTL2) is a secreted factor normally abundantly produced in mesenchymal lineage cells such as adipocytes and fibroblasts, but its loss contributes to the pathogenesis of lifestyle- or aging-related diseases. However, the function of ANGPTL2 in chondrocytes, which are also differentiated from mesenchymal stem cells, remains unclear. Here, we investigate whether ANGPTL2 is expressed in or functions in chondrocytes. METHODS: First, we evaluated Angptl2 expression during chondrocyte differentiation using chondrogenic ATDC5 cells and wild-type epiphyseal cartilage of newborn mice. We next assessed ANGPTL2 function in chondrogenic differentiation and associated signaling using Angptl2 knockdown ATDC5 cells and Angptl2 knockout mice. RESULTS: ANGPTL2 is expressed in chondrocytes, particularly those located in resting and proliferative zones, and accumulates in ECM surrounding chondrocytes. Interestingly, long bone growth was retarded in Angptl2 knockout mice from neonatal to adult stages via attenuation of chondrocyte differentiation. Both in vivo and in vitro experiments show that changes in ANGPTL2 expression can also alter p38 mitogen-activated protein kinase (MAPK) activity mediated by integrin α5ß1. CONCLUSION: ANGPTL2 contributes to chondrocyte differentiation and subsequent endochondral ossification through α5ß1 integrin and p38 MAPK signaling during bone growth. Our findings provide insight into molecular mechanisms governing communication between chondrocytes and surrounding ECM components in bone growth activities.


Asunto(s)
Proteínas Similares a la Angiopoyetina/fisiología , Desarrollo Óseo/fisiología , Proteína 2 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina/metabolismo , Animales , Animales Recién Nacidos , Diferenciación Celular/fisiología , Células Cultivadas , Condrocitos/citología , Condrocitos/metabolismo , Condrogénesis/fisiología , Inhibidores Enzimáticos/farmacocinética , Fémur/crecimiento & desarrollo , Imidazoles/farmacocinética , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas Matrilinas/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica , Piridinas/farmacocinética , Tibia/crecimiento & desarrollo
17.
J Microsc ; 268(3): 230-238, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28686305

RESUMEN

We have developed an analytical method to determine the segregation levels on the same tilt boundaries (TBs) at the same nanoscopic location by a joint use of atom probe tomography and scanning transmission electron microscopy, and discussed the mechanism of oxygen segregation at TBs in silicon ingots in terms of bond distortions around the TBs. The three-dimensional distribution of oxygen atoms was determined at the typical small- and large-angle TBs by atom probe tomography with a low impurity detection limit (0.01 at.% on a TB plane) simultaneously with high spatial resolution (about 0.4 nm). The three-dimensional distribution was correlated with the atomic stress around the TBs; the stress at large-angle TBs was estimated by ab initio calculations based on atomic resolution scanning transmission electron microscopy data and that at small-angle TBs were calculated with the elastic theory based on dark-field transmission electron microscopy data. Oxygen atoms would segregate at bond-centred sites under tensile stress above about 2 GPa, so as to attain a more stable bonding network by reducing the local stress. The number of oxygen atoms segregating in a unit TB area NGB (in atoms nm-2 ) was determined to be proportional to both the number of the atomic sites under tensile stress in a unit TB area nbc and the average concentration of oxygen atoms around the TB [Oi ] (in at.%) with NGB ∼ 50 nbc [Oi ].

18.
J Neuromuscul Dis ; 3(2): 201-207, 2016 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-27854222

RESUMEN

BACKGROUND AND OBJECTIVES: Cell transplantation is a promising therapy for several muscle diseases, including Duchenne muscular dystrophy. Satellite cells are stem cells in skeletal muscle that provide an important cell source for transplantation therapy. However, culture of satellite cells in vitro causes them to lose their undifferentiated state, associated with reduced transplantation efficiency. It is therefore necessary to develop optimal culture conditions for maintaining the undifferentiated state of satellite cells. METHODS: Primary satellite cells were cultured with or without leukemia inhibitory factor (LIF). The expression of undifferentiation and differentiation markers, and the transplantation efficiency were analyzed. RESULTS: LIF-treated satellite cells showed increased expression of Pax7, and enhanced transplantation efficiency in a mouse model of Duchenne muscular dystrophy. CONCLUSIONS: Our study showed that the treatment with LIF effectively maintained the undifferentiated state of satellite cells, and enhanced their transplantation efficiency. These results will contribute to the optimization of culture conditions for cell transplantation therapy.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Factor Inhibidor de Leucemia/farmacología , Músculo Esquelético/citología , Células Satélite del Músculo Esquelético/efectos de los fármacos , Animales , Técnicas de Cultivo de Célula , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Distrofia Muscular de Duchenne/terapia , Células Satélite del Músculo Esquelético/trasplante
19.
Clin Genet ; 90(6): 526-535, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27434533

RESUMEN

Joubert syndrome (JS) is rare recessive disorders characterized by the combination of hypoplasia/aplasia of the cerebellar vermis, thickened and elongated superior cerebellar peduncles, and a deep interpeduncular fossa which is defined by neuroimaging and is termed the 'molar tooth sign'. JS is genetically highly heterogeneous, with at least 29 disease genes being involved. To further understand the genetic causes of JS, we performed whole-exome sequencing in 24 newly recruited JS families. Together with six previously reported families, we identified causative mutations in 25 out of 30 (24 + 6) families (83.3%). We identified eight mutated genes in 27 (21 + 6) Japanese families, TMEM67 (7/27, 25.9%) and CEP290 (6/27, 22.2%) were the most commonly mutated. Interestingly, 9 of 12 CEP290 disease alleles were c.6012-12T>A (75.0%), an allele that has not been reported in non-Japanese populations. Therefore c.6012-12T>A is a common allele in the Japanese population. Importantly, one Japanese and one Omani families carried compound biallelic mutations in two distinct genes (TMEM67/RPGRIP1L and TMEM138/BBS1, respectively). BBS1 is the causative gene in Bardet-Biedl syndrome. These concomitant mutations led to severe and/or complex clinical features in the patients, suggesting combined effects of different mutant genes.


Asunto(s)
Anomalías Múltiples/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Antígenos de Neoplasias/genética , Cerebelo/anomalías , Anomalías del Ojo/genética , Enfermedades Renales Quísticas/genética , Proteínas de la Membrana/genética , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Neoplasias/genética , Retina/anomalías , Anomalías Múltiples/diagnóstico por imagen , Anomalías Múltiples/epidemiología , Anomalías Múltiples/fisiopatología , Alelos , Proteínas de Ciclo Celular , Cerebelo/diagnóstico por imagen , Cerebelo/fisiopatología , Proteínas del Citoesqueleto , Anomalías del Ojo/diagnóstico por imagen , Anomalías del Ojo/epidemiología , Anomalías del Ojo/fisiopatología , Femenino , Heterogeneidad Genética , Predisposición Genética a la Enfermedad , Humanos , Japón/epidemiología , Enfermedades Renales Quísticas/diagnóstico por imagen , Enfermedades Renales Quísticas/epidemiología , Enfermedades Renales Quísticas/fisiopatología , Masculino , Mutación , Omán/epidemiología , Linaje , Retina/diagnóstico por imagen , Retina/fisiopatología
20.
Med Oral Patol Oral Cir Bucal ; 21(3): e341-8, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27031062

RESUMEN

BACKGROUND: 18F-fluoro-2-deoxy-D-glucose (18F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18F-FDG accumulation in neck-related muscles of patients after ND for oral cancer. MATERIAL AND METHODS: 18F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers. RESULTS: According to the extent of ND of cervical lymph nodes, the rate of patients with 18F-FDG-PET-positive areas increased in the trapezius, sternocleidomastoid, and posterior neck muscles of the surgical and/or non-surgical sides. In addition, SUVmax of 18F-FDG-PET-positive areas in the trapezius and sternocleidomastoid muscles were increased according to the extent of the ND. CONCLUSIONS: In evaluating 18F-FDG accumulations after ND for oral cancers, we should pay attention to the 18F-FDG distributions in neck-related muscles including the non-surgical side as false-positive findings.


Asunto(s)
Fluorodesoxiglucosa F18/farmacocinética , Neoplasias de la Boca/diagnóstico por imagen , Disección del Cuello , Radiofármacos/farmacocinética , Humanos , Metástasis Linfática , Neoplasias de la Boca/patología , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X
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