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1.
Brain Nerve ; 69(9): 1035-1040, 2017 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-28900066

RESUMO

Recent advancement in magnetic resonance spectroscopy (MRS) has elucidated the pathophysiology of mental illness, including schizophrenia. MRS is a neuroimaging technique that non-invasively measures chemicals, using nuclear magnetic resonance. This narrative review explains proton MRS (1H-MRS) and introduces pivotal studies to examine a glutamate hypothesis for schizophrenia, employing 1H-MRS.


Assuntos
Ácido Glutâmico/metabolismo , Esquizofrenia/diagnóstico por imagem , Encéfalo/metabolismo , Química Encefálica , Ácido Glutâmico/análise , Humanos , Espectroscopia de Prótons por Ressonância Magnética , Esquizofrenia/metabolismo
2.
Sci Rep ; 6: 19947, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26795237

RESUMO

We describe a flexible capacitance-type sensor that can detect an approaching human without contact, fabricated by developing and applying duplex conductive-ink printing to a film substrate. The results of our calculations show that the difference in size between the top and bottom electrodes of the sensor allows for the spatial extension of the electric field distribution over the electrodes. Hence, such a component functions as a proximity sensor. This thin and light device with a large form factor can be arranged at various places, including curved surfaces and the back of objects such that it is unnoticeable. In our experiment, we attached it to the back of a bed, and found that our device successfully detected the breathing of a subject on the bed without contacting his body. This should contribute to reducing the physical and psychological discomfort among patients during medical checks, or when their condition is being monitored.


Assuntos
Técnicas Biossensoriais/instrumentação , Testes Respiratórios/instrumentação , Impressão/instrumentação , Respiração , Simulação por Computador , Capacitância Elétrica , Eletrodos , Humanos
3.
Chem Commun (Camb) ; (10): 1255-7, 2009 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-19240891

RESUMO

The metallophthalocyanine complex Cr(TBPC)OTf works as a highly efficient, recyclable Lewis acid catalyst for the regio- and stereoselective rearrangements of epoxides to aldehydes.


Assuntos
Ácidos/química , Aldeídos/química , Compostos de Epóxi/química , Metaloporfirinas/química , Catálise , Estrutura Molecular , Estereoisomerismo
4.
Chemistry ; 10(24): 6294-312, 2004 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-15526320

RESUMO

Tetraazaporphyrins (TAPs), phthalocyanines (Pcs), naphthalocyanines (Ncs), and anthracocyanines (Acs) with four tert-butyl groups attached at similar positions have been synthesized, and their electronic absorption, magnetic circular dichroism (MCD), IR, and voltammetric properties were studied and interpreted with the help of quantum-mechanical calculations. Through the preparation of a series of compounds with the same number of the same substituent, the effects of the increase in the size of the ring system were clearly derived. The main results may be summarized as follows. 1) The Q band shifts to longer wavelength and its intensity increases, but with decreasing degree of change with increasing molecular size. If the size of the effect of benzene directly fused to the TAP skeleton is set at unity, the effects of the second and third benzene units are roughly 0.8 and 0.5, respectively. 2) The splitting of the Q bands in metal-free compounds decreases with increasing molecular size, so that the Q bands of H2Nc and H2Ac appear as single bands. 3) The magnitude of the orbital angular momentum of the excited state of the ligand decreases with increasing molecular size. 4) Interestingly, the ring current, as judged from the positions of pyrrole proton signals in the 1H NMR spectrum, appears to decrease with increasing molecular size. 5) The first reduction potential becomes less negative, but only slightly, whereas the first oxidation potential shows a marked shift to less positive values with increasing molecular size, indicating that the HOMO destabilizes significantly as the molecule becomes larger. 6) In 5), the extent of the HOMO destabilization with molecular size differs depending on the central metal, so metals producing smaller destabilization effects can allow larger macrocycles. Of the metals studied, the most effective is cobalt, and the practical size limit is represented by the Acs. 7) The IR spectra become simpler the larger the molecule, and the main bands were assigned by DFT calculations. 8) The trend in experimentally determined redox potentials and electronic absorption and MCD spectra were reasonably reproduced by MO calculations using the ZINDO/S Hamiltonian. 9) EPR data for several metallocomplexes are also reported.


Assuntos
Carbocianinas/química , Indóis/química , Protoporfirinas/química , Carbocianinas/síntese química , Eletroquímica/métodos , Indóis/síntese química , Isoindóis , Modelos Moleculares , Protoporfirinas/síntese química , Teoria Quântica , Espectrofotometria Infravermelho
5.
J Am Chem Soc ; 126(31): 9554-5, 2004 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-15291555

RESUMO

Chromium(III) tetraphenylporphyrin triflate, Cr(TPP)OTf, works as an efficient and characteristic Lewis acid catalyst in the regio- and stereoselective rearrangement of epoxides to aldehydes. This Cr(TPP)OTf-catalyzed reaction is an operationally simple and especially convenient method for synthesizing optically active beta-siloxy aldehydes from 2,3-epoxy silyl ethers which are readily available in enantiomerically enriched forms by the Sharpless epoxidation of allylic alcohols followed by silylation.

6.
Drug Dev Ind Pharm ; 30(2): 151-61, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15089049

RESUMO

Stomatitis is a harmful side effect induced by high and/or multiple dosing of cytotoxic drugs such as 5-fluorouracil. Allopurinol mouthwash has been used to prevent stomatitis induced by cancer chemotherapy. In the present study, the pharmaceutical utility of allopurinol mouthwash (Alkox-mw), which consists of polyethylene(oxide) (Alkox) and iota-carrageenan (INA), was investigated as a possible material for a new oral dosage preparation for improving the adhesiveness onto the oral mucosa. From the observation of the gel formation, which was studied as a function of the variety of the added Alkox and/or INA, the preferential compositions of Alkox-mw (Alkox:INA % ratio) seemed to be 1.0:(0-1.0) and (0-3.0):0.4, respectively. The adhesiveness and the spinnability of various allopurinol mouthwashes were also investigated using a creep meter. The adhesiveness of Alkox-mw increased with the increase in the amount of added Alkox. Furthermore, the adhesion force of Alkox-mw was greater than that of allopurinol mouthwash consisting of sodium carboxymethylcellulose (CMC-Na). From the in vitro assessment of mimicking the effusion of the allopurinol mouthwashes from the surface of the oral mucosa, the effusion of Alkox-mws was retarded by the added Alkox. The results obtained in the present study suggest that Alkox-mws may be useful as a new dosage form that adheres to the oral mucosa.


Assuntos
Alopurinol/química , Carragenina/química , Inibidores Enzimáticos/química , Antissépticos Bucais , Polietilenoglicóis/química , Adesividade , Alopurinol/administração & dosagem , Carboximetilcelulose Sódica/química , Elasticidade , Inibidores Enzimáticos/administração & dosagem , Géis , Mucosa Bucal , Viscosidade
7.
Int J Pharm ; 267(1-2): 141-9, 2003 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-14602392

RESUMO

The release behavior of diethylhexyl phthalate (DEHP) from polyvinyl chloride (PVC) tubing, which composes materials in an intravenous administration set (IAS), was investigated using polyoxyethylated hydrogenated castor oil (HCO60) in physiological saline (PS), distilled water for injection (DWI), and ribose, fructose, and glucose (TZ) solutions. The amount of DEHP released increased with increasing HCO60 concentration, and the cumulative amount of DEHP released after 4h increased in the following order: 50% TZ

Assuntos
Óleo de Rícino/análogos & derivados , Óleo de Rícino/química , Dietilexilftalato/farmacocinética , Cloreto de Polivinila/química , Cromatografia Líquida de Alta Pressão , Dietilexilftalato/química , Frutose/química , Glucose/química , Infusões Intravenosas/métodos , Micelas , Ribose/química , Fatores de Tempo
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