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1.
Chem Commun (Camb) ; 60(24): 3299-3302, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38426265

RESUMO

Sunlight-driven photocatalytic water splitting shows promise for green H2 production. In an attempt to achieve seawater splitting, we constructed a new stoichiometric brine splitting system that produces H2 along with Cl2 instead of O2. Cl2-a more potent high-value-added oxidant than O2-was obtained with 100% selectivity over 10 h by adjusting the solution pH to acidic using a UV-light-driven Pt-loaded TiO2 photocatalyst. Our new photosynthesis system can permit economically feasible solar chemical production.

2.
Case Rep Pediatr ; 2022: 9844820, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529828

RESUMO

Perampanel is a noncompetitive, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid glutamate receptor antagonist. Herein, we report a case of increased perampanel plasma concentration and impaired consciousness triggered by an infection. The patient had refractory epilepsy associated with hemimegalencephaly. During adolescence, perampanel (maximum dose, 10 mg, oral), valproic acid, clobazam, and lacosamide were administered for seizure control. He was admitted to our hospital with high fever, impaired consciousness, and elevated perampanel plasma level (from 1,300 to 1,790 ng/mL), but with no increase in the concentration of other antiseizure medications. Further examinations (blood, cerebrospinal fluid, brain magnetic resonance images, and electroencephalogram) revealed no physical cause for impaired consciousness. After discontinuation of perampanel, his level of consciousness gradually improved. The pharmacokinetics of perampanel may be modified by both hemimegalencephaly and infection, resulting in an elevated plasma concentration of perampanel. This case underlines the importance of monitoring perampanel plasma concentration in patients with underlying brain disease who develop an infection.

3.
Neurol Genet ; 6(6): e524, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33134519

RESUMO

OBJECTIVE: To further clarify the molecular pathogenesis of RNA polymerase III (Pol III)-related leukodystrophy caused by biallelic POLR1C variants at a cellular level and potential effects on its downstream genes. METHODS: Exome analysis and molecular functional studies using cell expression and long-read sequencing analyses were performed on 1 family with hypomyelinating leukodystrophy showing no clinical and MRI findings characteristic of Pol III-related leukodystrophy other than hypomyelination. RESULTS: Biallelic novel POLR1C alterations, c.167T>A, p.M56K and c.595A>T, p.I199F, were identified as causal variants. Functional analyses showed that these variants not only resulted in altered protein subcellular localization and decreased protein expression but also caused abnormal inclusion of introns in 85% of the POLR1C transcripts in patient cells. Unexpectedly, allelic segregation analysis in each carrier parent revealed that each heterozygous variant also caused the inclusion of introns on both mutant and wild-type alleles. These findings suggest that the abnormal splicing is not direct consequences of the variants, but rather reflect the downstream effect of the variants in dysregulating splicing of POLR1C, and potentially other target genes. CONCLUSIONS: The lack of characteristic clinical findings in this family confirmed the broad clinical spectrum of Pol III-related leukodystrophy. Molecular studies suggested that dysregulation of splicing is the potential downstream pathomechanism for POLR1C variants.

4.
ACS Macro Lett ; 6(4): 345-349, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35610858

RESUMO

We developed flexible polymeric "heat-guiding materials" by simply drawing bacterial cellulose (BC) hydrogels to align the cellulose nanofibers and form "nanopapers" with anisotropic thermal conductivity. The in-plane anisotropy of thermal conductivity between the drawn and transverse directions increased as the draw ratio increased. For the drawn BC nanopapers, the coefficient of thermal expansion was found to be inversely correlated with the thermal diffusivity. We fabricated a planar spiral sheet by assembling the drawn BC strips to visualize the "heat flux controllability". The coexistence of heat-diffusing and heat-insulating capacities within the single nanopaper plane could help to cool future thin electronics.

5.
Biomacromolecules ; 16(7): 2220-7, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26106810

RESUMO

The thermal conductive properties, including the thermal diffusivity and resultant thermal conductivity, of nonwoven nanocellulose sheets were investigated by separately measuring the thermal diffusivity of the sheets in the in-plane and thickness directions with a periodic heating method. The cross-sectional area (or width) of the cellulose crystallites was the main determinant of the thermal conductive properties. Thus, the results strongly indicate that there is a crystallite size effect on phonon conduction within the nanocellulose sheets. The results also indicated that there is a large interfacial thermal resistance between the nanocellulose surfaces. The phonon propagation velocity (i.e., the sound velocity) within the nanocellulose sheets was estimated to be ∼800 m/s based on the relationship between the thermal diffusivities and crystallite widths. The resulting in-plane thermal conductivity of the tunicate nanocellulose sheet was calculated to be ∼2.5 W/mK, markedly higher than other plastic films available for flexible electronic devices.


Assuntos
Celulose/química , Nanoestruturas/química , Condutividade Térmica
6.
Rev Sci Instrum ; 79(10): 103101, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044696

RESUMO

We developed a high resolution Michelson interferometer with a two-frequency He-Ne laser positioning system in order to stabilize the relative phase of a pulse pair. The control resolution corresponded to a 12 as time resolution or a phase of 1.5 degrees at 900 nm. This high resolution Michelson interferometer can generate a phase-locked pulse pair either with a specific relative phase such as 0 or pi radians or with an arbitrary phase. Coherent control of an InAs self-assembled quantum dot was demonstrated using the high resolution Michelson interferometer with a microspectroscopy system.

7.
J Am Chem Soc ; 124(24): 6824-5, 2002 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-12059193

RESUMO

Pyranopyrandiones were prepared by a novel ruthenium-catalyzed carbonylative dimerization of cyclopropenones via C-C bond cleavage. For example, treatment of dipropylcyclopropenone with a catalytic amount of Ru3(CO)12 and NEt3 in THF under 15 atm of carbon monoxide at 140 degrees C for 20 h gave a novel functional monomer, 3,4,7,8-tetrapropylpyrano[6,5-e]pyran-2,6-dione, in an isolated yield of 81%. Unsymmetrically substituted pyranopyrandiones were also obtained by ruthenium-catalyzed carbonylative coupling of cyclopropenones with alkynes under similar reaction conditions.

8.
J Am Chem Soc ; 124(2): 186-7, 2002 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-11782166

RESUMO

[RuCl2(CO)3]2/dppp is shown to be a highly effective catalyst system for the first intramolecular oxidative amination of a variety of aminoalkenes when it is used concomitantly with K2CO3 and allyl acetate in N-methylpiperidine, to give the corresponding cyclic imines and indoles in excellent yields. For example, the reaction of 2,2-diphenyl-4-pentenyl-1-amine performed in the presence of 2 mol % of [RuCl2(CO)3]2, 4 mol % of dppp, K2CO3, and allyl acetate in N-methylpiperidine at 140 degrees C for 8 h gives 4,4-diphenyl-2-methyl-1-pyrroline in quantitative (>99%) yield.

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