Magnetic Resonance Spectroscopy Methods
Mostrando 1-12 de 102 artigos, teses e dissertações.
-
1. Attention-deficit/hyperactivity disorder and brain metabolites from proton magnetic resonance spectroscopy: a systematic review and meta-analysis protocol
Abstract Despite major advances in the study of the brain, investigations on neurochemistry in vivo still lack the solid ground of more established methods, such as structural and functional magnetic resonance imaging. Proton magnetic resonance spectroscopy (MRS) is a technique that might potentially fill in this gap. Nevertheless, studies using this approac
Trends Psychiatry Psychother.. Publicado em: 2021-03
-
2. Absolute Configuration of (−)-Cubebin, a Classical Lignan with Pharmacological Potential, Defined by Means of Chiroptical Spectroscopy
This work describes the first determination of the absolute configuration (AC) of (−)-cubebin by means of electronic circular dichroism (ECD), supported by quantum chemical calculations. The comparison of experimental ECD with the corresponding quantum chemical prediction for the proper diastereoisomer resulted in the definitive assignment of the AC of the
J. Braz. Chem. Soc.. Publicado em: 2020-10
-
3. 1H NMR and Chemometric Methods to Estimate the Octane Number in Brazilian C Gasolines
Brazilian gasoline type C can be purchased with octane number as the main difference. This quality parameter directly affects the price. Intermediate formulations may not be easily distinguished from conform samples due to similarity in visual appearance and physicochemical properties. The use of anhydrous ethanol as an additive also influences the octane va
J. Braz. Chem. Soc.. Publicado em: 2020-08
-
4. ANÁLISE DE AMOSTRAS DE COMBUSTÍVEIS POR FOTOMETRIA, NIR PORTÁTIL E RMN DE 1H - UMA COMPARAÇÃO COM OS RESULTADOS ENCONTRADOS POR TÉCNICAS NORMATIZADAS
It has been recurring adulterations in fuels (such as gasoline, ethanol and diesel), being necessary the exploration of the use of more modern analytical techniques capable of controlling the quality of these fuels, since some regulated tests may be inefficient to detect the adulteration. Among them, it is highlighted proton nuclear magnetic resonance (1H NM
Quím. Nova. Publicado em: 2020-02
-
5. Well Defined Rich Electronic Structure: Facile Approach for Nido-Carborane Fused Azaspirodecaniums in Water Solution
A novel bis-dumbbell shape of a multi cation around a azaspirodecanium combined with nido-carborane was prepared in a single step in good yield starting from pyrrolidine and 1,3-dichloropropane to give one compound and from piperidine and 1,4-dichlorobutane to give the other. This is the first report of an electrolyte azaspirodecanium-boron-cluster structure
J. Braz. Chem. Soc.. Publicado em: 2020-01
-
6. Seminal citrate is superior to PSA for detecting clinically significant prostate cancer
ABSTRACT Purpose: To establish whether the citrate concentration in the seminal fluid ([CITRATE]) measured by means of high-resolution nuclear magnetic resonance spectroscopy (1HNMRS) is superior to the serum prostate-specific antigen (PSA) concentration in detecting of clinically significant prostate cancer (csPCa) in men with persistently elevated PSA. M
Int. braz j urol.. Publicado em: 20/12/2019
-
7. FOODÔMICA POR RMN DE 1H PARA MONITORAMENTO DA ESTABILIDADE OXIDATIVA DE MARGARINAS SUBMETIDAS AO TRATAMENTO TÉRMICO
Foods with high lipid contents are susceptible to deterioration by oxidative processes that lead to the formation of food rancid. Determining the chemical nature of lipid oxidation products presents a nutritional and health interest due to the possibility of formation of compounds related to the development of degenerative diseases such as Parkinson’s and
Quím. Nova. Publicado em: 21/10/2019
-
8. Water-Soluble Benzazole Dyes Fluorescent by ESIPT: Structural Characterization, Photophysical Properties and Its Application as a Probe for Direct Staining of Helminths
A series of four water-soluble benzazole dyes that emit fluorescence by the excited state intramolecular proton transfer (ESIPT) mechanism were structurally characterized by Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR) attached proton test (APT) and mass spectrometry. Their photophysical properties were systemat
J. Braz. Chem. Soc.. Publicado em: 2019-03
-
9. A Simple and High-yield Synthesis of Hexadecyl Ferulate and Its In Vitro Antioxidant Potential
ABSTRACT Ferulic acid (FA) is a phenolic compound with well-known antioxidant potential that can be used as a promising anti-inflammatory and anti-cancer molecule. Furthermore, it has been reported to have neuroprotective activity. One of the main problems, which limit its clinical use, is its low bioavailability when administered orally. This limitation can
Braz. arch. biol. technol.. Publicado em: 14/11/2018
-
10. Kavalactones and Benzoic Acid Derivatives from Leaves of Piper fuligineum Kunth (Piperaceae)
The known kavalactones (E)-4-methoxy-6-styryl-2H-pyran-2-one, 4-methoxy-6-(3-phenyloxiran-2-yl)-2H-pyran-2-one, 6-(1,2-dihydroxy-2-phenylethyl)-4-methoxy-2H-pyran-2-one, the three benzoic acid derivatives methyl-4-methoxy-3-(3'-methyl-2'-butenyl)benzoate and methyl 2,2-dimethyl-4-oxochroman-6-carboxylate, and a new methyl 4-methoxy-3-(3-methylbut-2-enoyl)ben
J. Braz. Chem. Soc.. Publicado em: 2018-06
-
11. Pattern recognition of abscesses and brain tumors through MR spectroscopy: Comparison of experimental conditions and radiological findings
Abstract Introduction The interpretation of brain tumors and abscesses MR spectra is complex and subjective. In clinical practice, different experimental conditions such as field strength or echo time (TE) reveal different metabolite information. Our study aims to show in which scenarios magnetic resonance spectroscopy can differentiate among brain tumors,
Res. Biomed. Eng.. Publicado em: 17/08/2017
-
12. Screening of the in vitro antileishmanial activities of compounds and secondary metabolites isolated from Maytenus guianensis Klotzsch ex Reissek (Celastraceae) chichuá Amazon
Abstract INTRODUCTION Maytenus guianensis is a member of the Celastraceae family that is used in traditional medicine, particularly for its anti-parasitic and anti-cancer effects. To explore the ethnopharmacological potential of this plant, the present study was designed to screen the in vitro antileishmanial activities of extracts and compounds isolated fr
Rev. Soc. Bras. Med. Trop.. Publicado em: 2016-10