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1.
J Am Chem Soc ; 146(6): 3844-3853, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38193701

RESUMEN

Developing electrochemical high-energy storage systems is of crucial importance toward a green and sustainable energy supply. A promising candidate is fluoride-ion batteries (FIBs), which can deliver a much higher volumetric energy density than lithium-ion batteries. However, typical metal fluoride cathodes with conversion-type reactions cause a low-rate capability. Recently, layered perovskite oxides and oxyfluorides, such as LaSrMnO4 and Sr3Fe2O5F2, have been reported to exhibit relatively high rate performance and cycle stability compared to typical metal fluoride cathodes with conversion-type reactions, but their discharge capacities (∼118 mA h/g) are lower than those of typical cathodes used in lithium-ion batteries. Here, we show that double-layered perovskite oxyfluoride La1.2Sr1.8Mn2O7-δF2 exhibits (de) intercalation of two fluoride ions to rock-salt slabs and further (de) intercalation of excess fluoride ions to the perovskite layer, leading to a reversible capacity of 200 mA h/g. The additional fluoride-ion intercalation leads to the formation of O-O bond in the structure for charge compensation (i.e., anion redox). These results highlight the layered perovskite oxyfluorides as a new class of active materials for the construction of high-performance FIBs.

2.
RSC Adv ; 13(25): 17114-17120, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37293473

RESUMEN

Silicon has been considered to be one of the most promising anode active materials for next-generation lithium-ion batteries due to its large theoretical capacity (4200 mA h g-1, Li22Si5). However, silicon anodes suffer from degradation due to large volume expansion and contraction. To control the ideal particle morphology, an experimental method is required to analyze anisotropic diffusion and surface reaction phenomena. This study investigates the anisotropy of the silicon-lithium alloying reaction using electrochemical measurements and Si K-edge X-ray absorption spectroscopy on silicon single crystals. During the electrochemical reduction process in lithium-ion battery systems, the continuous formation of solid electrolyte interphase (SEI) films prevents the achievement of steady-state conditions. Instead, the physical contact between silicon single crystals and lithium metals can prevent the effect of SEI formation. The apparent diffusion coefficient and the surface reaction coefficient are determined from the progress of the alloying reaction analyzed by X-ray absorption spectroscopy. While the apparent diffusion coefficients show no clear anisotropy, the apparent surface reaction coefficient of Si (100) is more significant than that of Si (111). This finding indicates that the surface reaction of silicon governs the anisotropy of practical lithium alloying reaction for silicon anodes.

3.
Cureus ; 15(12): e51033, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38264384

RESUMEN

Spinocerebellar degeneration (SCD) is a progressive disease characterized by cerebellar ataxia or the posterior spinal cord. Among these, spinocerebellar ataxia type 31 (SCA31) is genetically more common in the Japanese population and is characterized by pure ataxia, resulting in severe disturbances in postural balance, with common falls. Therefore, rehabilitation is important to improve postural balance. Light touch is a known method of reducing postural sway, which acts with the light touching of an object with the body. We herein present a case of a patient with SCA31 who was trained in a standing position by lightly touching the back of the body to a wall surface. Dynamic interarticular coordination exercises were also performed as part of the rehabilitation program. As a result, even in the progressive SCA31, improvements in standing postural balance and activities of daily living contributed to improvements in the patient's postural balance. We followed the progress of postural control ability using the center of gravity sway measurement and electromyography and described some interesting characteristics of the patient's postural control ability in this report.

4.
ACS Cent Sci ; 6(12): 2326-2338, 2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33376794

RESUMEN

Nanostructured LiMnO2 integrated with Li3PO4 was successfully synthesized by the mechanical milling route and examined as a new series of positive electrode materials for rechargeable lithium batteries. Although uniform mixing at the atomic scale between LiMnO2 and Li3PO4 was not anticipated because of the noncompatibility of crystal structures for both phases, our study reveals that phosphorus ions with excess lithium ions dissolve into nanosize crystalline LiMnO2 as first evidenced by elemental mapping using STEM-EELS combined with total X-ray scattering, solid-state NMR spectroscopy, and a theoretical ab initio study. The integrated phase features a low-crystallinity metastable phase with a unique nanostructure; the phosphorus ion located at the tetrahedral site shares faces with adjacent lithium ions at slightly distorted octahedral sites. This phase delivers a large reversible capacity of ∼320 mA h g-1 as a high-energy positive electrode material in Li cells. The large reversible capacity originated from the contribution from the anionic redox of oxygen coupled with the cationic redox of Mn ions, as evidenced by operando soft XAS spectroscopy, and the superior reversibility of the anionic redox and the suppression of oxygen loss were also found by online electrochemical mass spectroscopy. The improved reversibility of the anionic redox originates from the presence of phosphorus ions associated with the suppression of oxygen dimerization, as supported by a theoretical study. From these results, the mechanistic foundations of nanostructured high-capacity positive electrode materials were established, and further chemical and physical optimization may lead to the development of next-generation electrochemical devices.

5.
Sci Rep ; 10(1): 7362, 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32355213

RESUMEN

The high anodic stability of electrolytes for rechargeable magnesium batteries enables the use of new positive electrodes, which can contribute to an increase in energy density. In this study, novel Ph3COMgCl-, Ph3SiOMgCl-, and B(OMgCl)3-based electrolytes were prepared with AlCl3 in triglyme. The Ph3COMgCl-based electrolyte showed anodic stability over 3.0 V vs. Mg but was chemically unstable, whereas the Ph3SiOMgCl-based electrolyte was chemically stable but featured lower anodic stability than the Ph3COMgCl-based electrolyte. Advantageously, the B(OMgCl)3-based electrolyte showed both anodic stability over 3.0 V vs. Mg (possibly due to the Lewis acidic nature of B in B(OMgCl)3) and chemical stability (possibly due to the hard acid character of B(OMgCl)3). B(OMgCl)3, which was prepared by reacting boric acid with a Grignard reagent, was characterized by nuclear magnetic resonance (NMR) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and X-ray absorption spectroscopy (XAS). The above analyses showed that B(OMgCl)3 has a complex structure featuring coordinated tetrahydrofuran molecules. 27Al NMR spectroscopy and Al K-edge XAS showed that when B(OMgCl)3 was present in the electrolyte, AlCl3 and AlCl2+ species were converted to AlCl4-. Mg K-edge XAS showed that the Mg species in B(OMgCl)3-based electrolytes are electrochemically positive. As a rechargeable magnesium battery, the full cell using the B(OMgCl)3-based electrolyte and a Mo6S8 Chevrel phase cathode showed stable charge-discharge cycles. Thus, B(OMgCl)3-based electrolytes, the anodic stability of which can be increased to ~3 V by the use of appropriate battery materials, are well suited for the development of practical Mg battery cathodes.

6.
ACS Appl Mater Interfaces ; 12(23): 25775-25785, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32395982

RESUMEN

To clarify the origin of the polarization of magnesium deposition/dissolution reactions, we combined electrochemical measurement, operando soft X-ray absorption spectroscopy (operando SXAS), Raman, and density functional theory (DFT) techniques to three different electrolytes: magnesium bis(trifluoromethanesulfonyl)amide (Mg(TFSA)2)/triglyme, magnesium borohydride (Mg(BH4)2)/tetrahydrofuran (THF), and Mg(TFSA)2/2-methyltetrahydrofuran (2-MeTHF). Cyclic voltammetry revealed that magnesium deposition/dissolution reactions occur in Mg(TFSA)2/triglyme and Mg(BH4)2/THF, while the reactions do not occur in Mg(TFSA)2/2-MeTHF. Raman spectroscopy shows that the [TFSA]- in the Mg(TFSA)2/triglyme electrolyte largely does not coordinate to the magnesium ions, while all of the [TFSA]- in Mg(TFSA)2/2-MeTHF and [BH4]- in Mg(BH4)2/THF coordinate to the magnesium ions. In operando SXAS measurements, the intermediate, such as the Mg+ ion, was not observed at potentials above the magnesium deposition potential, and the local structure distortion around the magnesium ions increases in all of the electrolytes at the magnesium electrode|electrolyte interface during the cathodic polarization. Our DFT calculation and X-ray photoelectron spectroscopy results indicate that the [TFSA]-, strongly bound to the magnesium ion in the Mg(TFSA)2/2-MeTHF electrolyte, undergoes reduction decomposition easily, instead of deposition of magnesium metal, which makes the electrolyte inactive electrochemically. In the Mg(BH4)2/THF electrolyte, because the [BH4]- coordinated to the magnesium ions is stable even under the potential of the magnesium deposition, the magnesium deposition is not inhibited by the decomposition of [BH4]-. Conversely, because [TFSA]- is weakly bound to the magnesium ion in Mg(TFSA)2/triglyme, the reduction decomposition occurs relatively slowly, which allows the magnesium deposition in the electrolyte.

7.
RSC Adv ; 10(65): 39875-39880, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-35515411

RESUMEN

Sulfur is a promising material for next-generation cathodes, owing to its high energy and low cost. However, sulfur cathodes have the disadvantage of serious cyclability issues due to the dissolution of polysulfides that form as intermediate products during discharge/charge cycling. Filling sulfur into the micropores of porous carbon is an effective method to suppress its dissolution. Although microporous carbon-supported sulfur cathodes show an electrochemical behavior different from that of the conventional sulfur ones, the corresponding reaction mechanism is not clearly understood. In this study, we focused on clarifying the reaction mechanism of microporous carbon-supported sulfur cathodes by operando soft X-ray absorption spectroscopy. In the microporous carbon support, sulfur was present as smaller fragments compared to conventional sulfur. During the first discharge process, the sulfur species in the microporous carbon were initially reduced to S6 2- and S2 2- and then to Li2S. The S6 2- and S2 2- species were observed first, with S2 2- being the main polysulfide species during the discharge process, while Li2S was produced in the final discharge process. The narrow pores of microporous carbon prevent the dissolution of polysulfides and influence the reaction mechanism of sulfur cathodes.

8.
Kyobu Geka ; 72(2): 128-131, 2019 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-30772878

RESUMEN

A 32-year-old man leaping down from the 3rd floor of his house got injured and was transferred to our center. Pseudoaneurysm at the aortic isthmus as well as pelvic and lower limb fractures were observed by computed tomography (CT) scan. Thoracic endovascular aortic repair(TEVAR)of the thoracic aorta was performed from zone 2, followed by external skeletal fixation. Postoperative chest X-ray revealed right hemothorax, and CT scan showed active bleeding from the right subclavian artery in addition to splenic artery pseudoaneurysm. A 10×60 mm covered stent was deployed at the right subclavian artery and coiling of the splenic artery was performed. He was discharged without complication. The timing and procedures of surgery are difficult to decide in treatment of aortic injury with multiple trauma, TEVAR makes quick control of bleeding possible by less invasive approach. Moreover, endovascular approach to the subclavian artery avoides median sternotomy.


Asunto(s)
Aneurisma Falso/cirugía , Aorta Torácica/lesiones , Aneurisma de la Aorta Torácica/cirugía , Procedimientos Endovasculares/métodos , Arteria Subclavia/lesiones , Adulto , Aneurisma Falso/etiología , Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/etiología , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Hemotórax/diagnóstico por imagen , Hemotórax/etiología , Humanos , Masculino , Huesos Pélvicos/lesiones , Stents , Arteria Subclavia/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Sci Rep ; 8(1): 15086, 2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30305719

RESUMEN

The charge-discharge capacity of lithium secondary batteries is dependent on how many lithium ions can be reversibly extracted from (charge) and inserted into (discharge) the electrode active materials. In contrast, large structural changes during charging/discharging are unavoidable for electrode materials with large capacities, and thus there is great demand for developing materials with reversible structures. Herein, we demonstrate a reversible rocksalt to amorphous phase transition involving anion redox in a Li2TiS3 electrode active material with NaCl-type structure. We revealed that the lithium extraction during charging involves a change in site of the sulfur atom and the formation of S-S disulfide bonds, leading to a decrease in the crystallinity. Our results show great promise for the development of long-life lithium insertion/extraction materials, because the structural change clarified here is somewhat similar to that of optical phase-change materials used in DVD-RW discs, which exhibit excellent reversibility of the transition between crystalline and amorphous phase.

10.
J Am Chem Soc ; 139(26): 8796-8799, 2017 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-28618780

RESUMEN

A unique charge/discharge mechanism of amorphous TiS4 is reported. Amorphous transition metal polysulfide electrodes exhibit anomalous charge/discharge performance and should have a unique charge/discharge mechanism: neither the typical intercalation/deintercalation mechanism nor the conversion-type one, but a mixture of the two. Analyzing the mechanism of such electrodes has been a challenge because fewer tools are available to examine the "amorphous" structure. It is revealed that the electrode undergoes two distinct structural changes: (i) the deformation and formation of S-S disulfide bonds and (ii) changes in the coordination number of titanium. These structural changes proceed continuously and concertedly for Li insertion/extraction. The results of this study provide a novel and unique model of amorphous electrode materials with significantly larger capacities.

11.
Chem Biol Drug Des ; 89(4): 475-481, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27743504

RESUMEN

Ginkgolides are terpene trilactones in Ginkgo biloba, a popular medicinal herb for memory disorders. Although ginkgolides are known for various neurobiological effects, their macromolecular target in brain is unknown. In this work, we employed benzophenone derivatives of ginkgolides to identify their binding target in brain. Photolabeling of bovine hippocampus homogenates identified a series of α-tubulin isotypes. Selective photolabeling of α-tubulin over ß-tubulin, which is equally abundant in brain, suggested that ginkgolides might modulate microtubule biology differently than typical microtubule-binding agents, such as taxol. In fact, ginkgolide A did not affect microtubule polymerization or cell proliferation; instead, it inhibited detyrosination of α-tubulin and reorientation of microtubule-organizing centers. Taken together, the current findings indicate that ginkgolides constitute a new class of microtubule-binding agents with distinct effects on α-tubulin biology.


Asunto(s)
Ginkgólidos/farmacología , Hipocampo/efectos de los fármacos , Etiquetas de Fotoafinidad , Animales , Línea Celular , Humanos , Ratones , Microtúbulos/efectos de los fármacos
12.
Bioorg Med Chem ; 24(21): 5148-5157, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27614918

RESUMEN

The blood-brain barrier permeability of ginkgolide B was examined using positron emission tomography (PET) probes of a 18F-incorporated ginkgolide B ([18F]-2) and a 11C-incorporated methylbenzyl-substituted ginkgolide B ([11C]-3). PET studies in monkeys showed low uptake of [18F]-2 into the brain, but small amounts of [11C]-3 were accumulated in the parenchyma. Furthermore, when cyclosporine A was preadministered to rats, the accumulation of [18F]-2 in the rat brain did not significantly change, however, the accumulation of [11C]-3 was five times higher than that in the control rat. These results provide effective approaches for investigating the drug potential of ginkgolides.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Ginkgólidos/farmacocinética , Lactonas/farmacocinética , Tomografía de Emisión de Positrones , Animales , Barrera Hematoencefálica/efectos de los fármacos , Encéfalo/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ginkgólidos/síntesis química , Ginkgólidos/química , Ginkgólidos/farmacología , Haplorrinos , Lactonas/síntesis química , Lactonas/química , Lactonas/farmacología , Estructura Molecular , Permeabilidad/efectos de los fármacos , Ratas , Relación Estructura-Actividad
13.
Jpn Clin Med ; 6: 15-20, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26441486

RESUMEN

We attempted to examine whether withdrawal from insulin therapy is or is not possible with administration of additional alogliptin and identify the contributing factors. The subjects were 43 adult patients with type 2 diabetes undergoing insulin therapy after admission. After glucotoxicity was removed, 25 mg alogliptin was additionally administered. Insulin was reduced by 15.6 ± 13.0 units (mean ± SD), and 17 patients (39.5%) completely withdrew from insulin therapy. Several factors were compared between the two groups of patients: those who could withdraw from insulin therapy and those who could not. The former group showed lower HbA1c levels on admission, a lower insulin dose before adding alogliptin, lower injection frequencies, and longer treatment histories prior to admission. Logistic regression analysis showed that lower insulin dose contributed significantly to withdrawal. These results suggest that a lower insulin dose is the best predictor for withdrawal from insulin therapy after adding alogliptin.

14.
J Infect Chemother ; 21(12): 857-63, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26423689

RESUMEN

BACKGROUND: Viral infection is one of the major causes of mortality in patients undergoing hematopoietic stem cell transplant (HSCT). Systemic infection of adenovirus (AdV) has emerged as a not uncommon viral infection with significant morbidity and mortality as with cytomegalovirus and Epstein-Barr virus infection. Routine surveillance for these viruses has become a clinical practice and subsequent preemptive therapy improves patients' outcomes; however, the effectiveness of preemptive therapy for AdV has not been fully investigated in patients with a lethal form of AdV infection. METHODS: Sequential AdV loads were retrospectively analyzed in children with fulminant AdV hepatitis after HSCT. RESULTS: The AdV DNA became detectable (1 × 10(4) copies/mL) as early as 2 weeks after HSCT. These levels reached >1 × 10(8) copies/mL at the onset of fulminant hepatitis. However, we determined that γ-glutamyltransferase levels were elevated to >100 IU/L at least 2 weeks before the diagnosis of hepatitis. CONCLUSIONS: Our observation raises the possibility that elevated γ-glutamyltransferase could be a sentinel marker for AdV hepatitis, which prompts elaborated monitoring of AdV load and targeted treatment.


Asunto(s)
Adenoviridae/genética , Infecciones por Adenovirus Humanos/virología , ADN Viral/genética , Hepatitis/virología , Adenoviridae/efectos de los fármacos , Infecciones por Adenovirus Humanos/tratamiento farmacológico , Adolescente , Antivirales/uso terapéutico , Niño , Citomegalovirus/efectos de los fármacos , Citomegalovirus/genética , Femenino , Trasplante de Células Madre Hematopoyéticas , Hepatitis/tratamiento farmacológico , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estudios Retrospectivos , Carga Viral/efectos de los fármacos , Carga Viral/métodos , Virosis/tratamiento farmacológico , Virosis/virología
15.
Sci Rep ; 5: 11081, 2015 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-26061742

RESUMEN

Low dark noise is a prerequisite for rod cells, which mediate our dim-light vision. The low dark noise is achieved by the extremely stable character of the rod visual pigment, rhodopsin, which evolved from less stable cone visual pigments. We have developed a biochemical method to quickly evaluate the thermal activation rate of visual pigments. Using an isomerization locked chromophore, we confirmed that thermal isomerization of the chromophore is the sole cause of thermal activation. Interestingly, we revealed an unexpected correlation between the thermal stability of the dark state and that of the active intermediate MetaII. Furthermore, we assessed key residues in rhodopsin and cone visual pigments by mutation analysis and identified two critical residues (E122 and I189) in the retinal binding pocket which account for the extremely low thermal activation rate of rhodopsin.


Asunto(s)
Multimerización de Proteína , Rodopsina/química , Rodopsina/metabolismo , Termodinámica , Aminoácidos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Retina/metabolismo
17.
Rev Sci Instrum ; 85(8): 084103, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25173283

RESUMEN

A novel spectro-electochemical cell for X-ray absorption spectroscopy in the tender X-ray region (TX-XAS) was designed and fabricated to investigate the electrochemical behavior of common battery materials with liquid electrolytes under in situ/operando conditions. The cell has several unique features, such as high X-ray transmittance, high signal to noise ratio, and high vacuum tightness. These features enable us quick and reliable XAS measurements. Operando P K-edge XAS measurements of an olivine-type LiFePO4 composite positive electrode were carried out to clarify its phosphorus environment during the electrochemical charging process. Results of spectral analysis show that there is no significant change in the oxidation state of phosphorus and in the coordination of the phosphate anions in the charging process, but a closer look of the consecutive XAS spectra suggests the shrinkage of the PO4 cage during the charging process, and the structural changes in a biphasic manner. These results demonstrate the usefulness of the cell for in situ/operando TX-XAS observations of light elements in practical batteries.

18.
Interact Cardiovasc Thorac Surg ; 19(4): 702-4, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24994698

RESUMEN

Arterial aneurysm rupture is one of the most critical complications in patients with vascular-type Ehlers-Danlos syndrome (vEDS). Here, we report a case of recurrent aneurysm rupture successfully treated by endovascular embolization. A 38-year old woman who underwent brachial artery ligation for a ruptured aneurysm was diagnosed postoperatively with vEDS. Impending rupture of a collateral artery aneurysm was encountered 5 months after the initial open surgery. Endovascular embolization with a liquid embolic agent was successfully performed. Given that arterial rupture can occur repeatedly in patients with vEDS, careful life-long follow-up is necessary.


Asunto(s)
Aneurisma Roto/etiología , Arteria Braquial , Síndrome de Ehlers-Danlos/complicaciones , Extremidad Superior/irrigación sanguínea , Adulto , Aneurisma Roto/diagnóstico , Aneurisma Roto/terapia , Arteria Braquial/diagnóstico por imagen , Arteria Braquial/cirugía , Síndrome de Ehlers-Danlos/diagnóstico , Embolización Terapéutica , Femenino , Humanos , Ligadura , Recurrencia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
19.
Interact Cardiovasc Thorac Surg ; 18(2): 250-2, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24218495

RESUMEN

Non-anastomotic graft rupture is a rare but critical complication after abdominal aortic aneurysm (AAA) repair. Therefore, identifying the rupture sites is important to perform endovascular stent grafting. A 78-year old man who had undergone Y-grafting for infrarenal AAA before 17 years was referred to our hospital with the complaints of abdominal pain. Computed tomography revealed acute pancreatitis and an enlargement around the grafted abdominal aorta. Contrast-enhanced ultrasonography revealed an extravazation from the graft body 1.5 cm distal to the proximal anastomosis, and endovascular stent grafting was successfully performed. Contrast-enhanced ultrasonography might be useful in detecting the graft rupture.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Rotura de la Aorta/diagnóstico por imagen , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Medios de Contraste , Procedimientos Endovasculares/instrumentación , Compuestos Férricos , Hierro , Óxidos , Falla de Prótesis , Ultrasonografía Doppler , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Rotura de la Aorta/etiología , Rotura de la Aorta/cirugía , Aortografía/métodos , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Humanos , Masculino , Valor Predictivo de las Pruebas , Reoperación , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
Nat Genet ; 45(8): 937-41, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23832011

RESUMEN

Juvenile myelomonocytic leukemia (JMML) is an intractable pediatric leukemia with poor prognosis whose molecular pathogenesis is poorly understood, except for somatic or germline mutations of RAS pathway genes, including PTPN11, NF1, NRAS, KRAS and CBL, in the majority of cases. To obtain a complete registry of gene mutations in JMML, whole-exome sequencing was performed for paired tumor-normal DNA from 13 individuals with JMML (cases), which was followed by deep sequencing of 8 target genes in 92 tumor samples. JMML was characterized by a paucity of gene mutations (0.85 non-silent mutations per sample) with somatic or germline RAS pathway involvement in 82 cases (89%). The SETBP1 and JAK3 genes were among common targets for secondary mutations. Mutations in the latter were often subclonal and may be involved in the progression rather than the initiation of leukemia, and these mutations associated with poor clinical outcome. Our findings provide new insights into the pathogenesis and progression of JMML.


Asunto(s)
Proteínas Portadoras/genética , Exoma , Janus Quinasa 3/genética , Leucemia Mielomonocítica Juvenil/genética , Mutación , Proteínas Nucleares/genética , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Mutación de Línea Germinal , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Recién Nacido , Leucemia Mielomonocítica Juvenil/metabolismo , Leucemia Mielomonocítica Juvenil/mortalidad , Masculino , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Transducción de Señal
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