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1.
Chem Phys Lipids ; 242: 105164, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34906552

RESUMO

The selection of an animal model is based on the pathological mechanism appropriate for experimental investigation because the therapeutic effect was low depending on the pathological occurrence mechanism. The purpose of this study is to elucidate the changes in lipid proton concentration in two animal models of nonalcoholic fatty liver disease (NAFLD): methionine and choline-deficient (MCD) diet and high-fat diet (HFD). We calculated the T2 relaxation time of 7 lipid protons (LP) in the 9.4 T MRS phantom experiment. The concentrations of LPs were adjusted for T2 and T2* of MCD, HFD, and CCl4 fatty liver animal models. Multivariate analysis and Pearson correlation were performed to analyze LP concentration, and the difference was investigated via Kendall correlation and independent t-test using LP composition ratio. The T2 relaxation time of each LP was accurately determined using phantom experiments. The in vivo magnetic resonance spectroscopy (MRS) data were obtained by quantifying the t2/t2* corrected LP concentration in the liver of the animal model. In case of MCD and HFD, there was an average difference in all LPs except 0.9 ppm LP, and the MCD and CCl4 groups showed differences in the average of all LPs. However, there was no difference between LP of HFD and CCl4 groups. A higher level of unsaturated fatty acids was found in the MCD fatty liver model than in HFD induced fatty liver.


Assuntos
Metionina , Hepatopatia Gordurosa não Alcoólica , Animais , Colina , Dieta Hiperlipídica , Modelos Animais de Doenças , Lipídeos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Prótons
2.
Artigo em Inglês | MEDLINE | ID: mdl-31569358

RESUMO

The purpose of this study is to design a backpack to push the lumbar region forward and confirm the change in the sagittal plane of the spine using radiography when wearing the backpack to present an effective backpack wearing method that can help spinal alignment. Place the question addressed in a broad context and highlight the purpose of the study. A total of 14 adult volunteers participated in the study. The study was carried out on the subjects without carrying a backpack, with a general backpack, and with a backpack designed to push the lumbar region forward. We investigated cervical, thoracic, lumbar, and sacral alignment under these three conditions. Lumbar lordosis showed a significant decrease in the state of wearing a general backpack compared to the case without a backpack, and a significant increase in the state of wearing a backpack designed to push the lumbar region forward rather than a general backpack. In addition, the sacral slope was significantly increased when carrying the backpack designed to push the lumbar region forward, compared to carrying the general backpack. There was a significant correlation between the sacral and lumbar alignment change when wearing the backpack compared to the state without a backpack. The results of this study indicate that wearing a backpack designed to push the lumbar region forward may contribute to the recovery of lumbar lordosis that is reduced when wearing a general backpack. This may be due to an increase in the sacral slope corresponding to the inferior angle of lumbar spine.


Assuntos
Vértebras Lombares/fisiologia , Região Lombossacral/fisiologia , Adulto , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Região Lombossacral/diagnóstico por imagem , Masculino , Adulto Jovem
3.
Korean J Radiol ; 20(1): 126-133, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30627028

RESUMO

Objective: To compare the lumbar vertebral bone marrow fat-signal fractions obtained from six-echo modified Dixon sequence (6-echo m-Dixon) with those from single-voxel magnetic resonance spectroscopy (MRS) in patients with low back pain. Materials and Methods: Vertebral bone marrow fat-signal fractions were quantified by 6-echo m-Dixon (repetition time [TR] = 7.2 ms, echo time (TE) = 1.21 ms, echo spacing = 1.1 ms, total imaging time = 50 seconds) and single-voxel MRS measurements in 25 targets (23 normal bone marrows, two focal lesions) from 24 patients. The point-resolved spectroscopy sequence was used for localized single-voxel MRS (TR = 3000 ms, TE = 35 ms, total scan time = 1 minute 42 seconds). A 2 × 2 × 1.5 cm3 voxel was placed within the normal L2 or L3 vertebral body, or other lesions including a compression fracture or metastasis. The bone marrow fat spectrum was characterized on the basis of the magnitude of measurable fat peaks and a priori knowledge of the chemical structure of triglycerides. The imaging-based fat-signal fraction results were then compared to the MRS-based results. Results: There was a strong correlation between m-Dixon and MRS-based fat-signal fractions (slope = 0.86, R2 = 0.88, p < 0.001). In Bland-Altman analysis, 92.0% (23/25) of the data points were within the limits of agreement. Bland-Altman plots revealed a slight but systematic error in the m-Dixon based fat-signal fraction, which showed a prevailing overestimation of small fat-signal fractions (< 20%) and underestimation of high fat-signal fractions (> 20%). Conclusion: Given its excellent agreement with single-voxel-MRS, 6-echo m-Dixon can be used for visual and quantitative evaluation of vertebral bone marrow fat in daily practice.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Medula Óssea/fisiologia , Vértebras Lombares/fisiologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Triglicerídeos/análise , Tecido Adiposo/patologia , Adulto , Idoso , Feminino , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/patologia , Humanos , Dor Lombar/diagnóstico , Dor Lombar/patologia , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/patologia
4.
Acad Radiol ; 25(12): 1595-1602, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29803754

RESUMO

RATIONALE AND OBJECTIVES: The aim of this study was to determine the optimal weighting factor (WF) for precise quantification using six-point interference Dixon fat percentage imaging by analyzing changes in WFs of fatty acid metabolites (FMs) in high-fat-induced fatty liver disease rat model. MATERIALS AND METHODS: Individual FM-related WFs were calculated based on concentration ratios of integrated areas of seven peak FMs with four phantom series. Ten 8-week-old male Sprague-Dawley rats were used for baseline quantification of fat in liver magnetic resonance imaging or magnetic resonance spectroscopy data. These seven lipid metabolites were then quantitatively analyzed. Spearman test was used for correlation analysis of different lipid proton concentrations. The most accurate WF for six-point interference Dixon fat percentage imaging was then determined. RESULTS: The seven lipid resonance WF values obtained from magnetic resonance spectroscopy data for three different oils (oleic, linoleic, and soybean) were different from each other. In lipid phantoms, except for the phantom containing oleic acid, changes in FP values were significantly different when WFs were changed in six-point interference Dixon fat percentage image. The seven lipid resonance WF values for the nonalcoholic fatty liver animal model were different from human subcutaneous adipose tissue lipid WF values. CONCLUSIONS: WF affected the calculation of six-point interference Dixon-based fat percentage imaging value in phantom experiment. If WF of liver parenchyma FM which is specific to each liver disease is applied, the accuracy of six-point interference Dixon fat percentage imaging can be further increased.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Tecido Adiposo/patologia , Animais , Modelos Animais de Doenças , Ácido Linoleico/metabolismo , Masculino , Ácido Oleico/metabolismo , Imagens de Fantasmas , Ratos , Ratos Sprague-Dawley , Óleo de Soja/metabolismo
5.
PLoS One ; 10(10): e0139874, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26460614

RESUMO

PURPOSE: To prospectively evaluate the changes in fatty acid concentration after administrating a 60% high-fat diet to a non-alcoholic fatty liver disease rat model and to perform a correlation analysis between fatty acid with molecular diffusion (Dtrue), perfusion-related diffusion (Dfast), and perfusion fraction (Pfraction). MATERIAL AND METHODS: This prospective study was approved by the appropriate ethics committee. Ten male Sprague-Dawley rats were fed a 60% high-fat diet until the study was finished. Point-resolved spectroscopy sequence 1H-MRS with TR = 1,500 msec, TE = 35 msec, NEX = 64, and 8×8×8 mm3 voxel was used to acquire magnetic resonance spectroscopy (MRS) data. Diffusion-weighted imaging was performed on a two-dimensional multi-b value spin echo planar image with the following parameters: repetition time msec/echo time msec, 4500 /63; field of view, 120×120 msec2; matrix, 128×128; section thickness, 3 mm; number of repetition, 8; and multiple b value, 0, 25, 50, 75, 100, 200, 500, 1000 sec/mm2. Baseline magnetic resonance imaging and magnetic resonance spectroscopy data (control) were acquired. 1H proton MRS and diffusion-weighted imaging were obtained every 2 weeks for 8 weeks. The individual contributions of the true molecular diffusion and the incoherent motions of water molecules in the capillary network to the apparent diffusion changes were estimated using a least-square nonlinear fitting in MatLab. A Wilcoxon signed-rank test with the Kruskal-Wallis test was used to compare each week's fatty acid mean quantification. Spearman's correlation coefficient was used to evaluate the correlation between each fatty acid (e.g., total lipid (TL), total saturated fatty acid (TSFA), total unsaturated fatty acid (TUSFA), total unsaturated bond (TUSB), and polyunsaturated bond (PUSB)) and intravoxel incoherent motion (IVIM) mapping images (e.g., Dtrue, Dfast, and Pfraction). RESULTS: The highest mean TL value was at week 8 (0.278 ± 0.10) after the administration of the 60% high-fat diet, followed by weeks 6, 4, 2, and 0. The concentration level (16.99±2.29) of TSFA at week 4 was the highest. No significant differences in the concentrations of TUSFA, TUSB, or PUSB were observed in different weeks. CONCLUSION: After the administration of the 60% high-fat diet in nonalcoholic fatty liver disease model, TL and TSFA depositions had significant changes. The mean concentrations of TUSFA, TUSB, PUSB did not significantly change. Total unsaturated fatty acid and polyunsaturated bond showed positive correlations with Dtrue and Pfraction.


Assuntos
Ácidos Graxos/metabolismo , Fígado/diagnóstico por imagem , Fígado/metabolismo , Imageamento por Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Modelos Animais de Doenças , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Radiografia , Ratos , Ratos Sprague-Dawley
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1609-10, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719415

RESUMO

In the title mol-ecular salt, C(15)H(17)N(2)O(+)·Br(-), the benzene and pyridinium rings form a dihedral angle of 83.0 (1)°. In the crystal, N-H⋯Br and N-H⋯O hydrogen bonds link the components into chains along [010]. These chains are linked by weak C-H⋯O and C-H⋯Br hydrogen bonds, forming a three-dimensional network.

7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): m1045-6, 2009 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21577407

RESUMO

The title compound, [Zn(C(8)H(6)O(3))(2)(C(12)H(12)N(2))](n), consists of [Zn(Hopa)(2)] (H(2)opa = 2-hydr-oxy-2-phenyl-acetic acid or mandelic acid) units bridged by 1,2-di-4-pyridylethane (bpe) ligands, forming a polymeric chain developing parallel to the b axis. The bridging bpe ligand is arranged around a twofold axis passing through the middle of the ethane C-C bond. The geometry around the Zn(II) ion is distorted octa-hedral, constructed by four O atoms from two Hopa(-) ligands and two N atoms from two bridging bpe ligands. O-H⋯O hydrogen bonds link the chains, forming a three-dimensional network.

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): m61-2, 2009 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21579957

RESUMO

The central part of the title centrosymmetric dinuclear complex, [Zn(2)(C(7)H(5)O(2))(4)(C(9)H(12)N(2))(2)], has a paddle-wheel conformation with four benzoate ligands bridging two symmetry-related Zn(II) ions. The distorted square-pyramidal coordination environment around the Zn(II) ion is completed by an N atom from a 4-(pyrrolidin-1-yl)pyridine ligand. The Zn⋯Zn separation of 2.9826 (12) Šdoes not represent a formal direct metal-metal bond. The Zn(II) ion is displaced by 0.381 (1) Šfrom the mean plane of the four basal O atoms. Two of the C atoms of the pyrrolidine ring are disordered over two sites with refined occupancies of 0.53 (2) and 0.47 (2).

9.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): m678-9, 2009 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-21583038

RESUMO

The title compound, [Ni(C(11)H(10)N(2)O(2))(2)](NO(3))(2), consists of an Ni(II) atom coordinated by two tridentate chelating di-2-pyridylmethane-diol [(2-py)(2)C(OH)(2)] ligands. The Ni(II) atom is located on an inversion center. The geometry around the Ni(II) atom is distorted octa-hedral. The gem-diol (2-py)(2)C(OH)(2) ligand adopts the coordination mode η(1):η(1):η(1). The Ni-N and Ni-O bond lengths are typical for high-spin Ni(II) in an octa-hedral environment [Ni-N = 2.094 (2) and 2.124 (3) Å, and Ni-O = 2.108 (3) Å]. One of the hydr-oxy H atoms is split over two positions which both inter-act with the nitrate anion. The occurence of different O-H⋯O hydrogen bonds leads to the formation of a layer parallel to the (101) plane.

10.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): m881-2, 2008 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21202752

RESUMO

In the title compound, [Cu(2)(C(7)H(5)O(2))(4)(C(10)H(9)N)(2)], the paddle-wheel-type dinuclear complex is constructed by four bridging benzoate groups and two terminal 6-methyl-quinoline ligands. The asymmetric unit contains one-half of the whole mol-ecule, and there is an inversion center at the mid-point of the Cu⋯Cu bond. The octa-hedral coordination of each Cu atom, with four O atoms in the equatorial plane, is completed by the N atom of the 6-methyl-quinoline mol-ecule [Cu-N = 2.212 (2) Å] and by another Cu atom [Cu⋯Cu = 2.6939 (13) Å]. The Cu atom lies 0.234 Šout of the plane of the four O atoms. The molecular packing is stabilized by one intramolecular C-H⋯O as well as C-H⋯π and π-π interactions.

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