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1.
Phytochemistry ; 200: 113249, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35609680

RESUMO

Eleven undescribed and three known pterocarpans were isolated and identified from the traditional Chinese medicine "Huang-qi", Astragali Radix (the root of Astragalus membranaceus var. mongholicus (Bunge) P.K.Hsiao). The structures of these pterocarpans were determined using spectroscopic, X-ray crystallographic, quantum chemical calculation, and chemical methods. Pterocarpans, almost exclusively distributed in the family of Leguminosae, are the second largest subgroup of isoflavanoids. However, pterocarpan glycoside number is limited, most of which are glucosides, and only one pterocarpan apioside was isolated from nature. Notably, nine rare apiosyl-containing pterocarpan glycosides were isolated and identified. The hypoglycemic activities of all these compounds were evaluated using α-glucosidase and DPP-IV inhibitory assays respectively, and some isolates displayed the α-glucosidase inhibitory function. The antioxidant activities of all compounds were evaluated using the ORAC and DPPH radical scavenging assays, respectively. All compounds exhibited varying degrees of oxygen radical absorbance capacity, and some compounds displayed DPPH radical scavenging ability.


Assuntos
Astragalus propinquus , Pterocarpanos , Astragalus propinquus/química , Glicosídeos , Medicina Tradicional Chinesa , alfa-Glucosidases
2.
J Asian Nat Prod Res ; 22(10): 905-913, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32654511

RESUMO

Three new (1-3) and 11 known (4-14) cycloartane-type triterpenoids were isolated from the root of Astragalus membranaceus var. mongholicus. Their structures were determined by spectroscopic analyses and chemical methods. Cycloartane-type triterpenoids are a class of major bioactive constituents in the root of A. membranaceus var. mongholicus, and the discovery of compounds 1-3 added new members of this kind of natural product. [Formula: see text].


Assuntos
Astragalus propinquus , Triterpenos , Estrutura Molecular
3.
Data Brief ; 21: 321-327, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30364612

RESUMO

Plumula nelumbinis is a well-known health food and a traditional Chinese medicine, is used in many countries around the world. For its pharmacological properties are related to its chemical composition, a ultra-performance liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) method was used to identify the flavonoids in P. nelumbinis. The first set of data shows the MS-MS Spectrograms of 12 flavonoid standards and 38 flavonoids detected in the P. nelumbinis from Xiangtan, Hunan province. The second set of data shows the total flavonoids content and the antioxidant activity of total flavonoid in P. nelumbinis from 13 habitats. The antioxidant activity were accomplished with 1,1-diphenyl-2-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC) and ferric reducing ability of plasma (FRAP) assays.

4.
Aviat Space Environ Med ; 85(2): 187-90, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24597165

RESUMO

BACKGROUND: The traditional water displacement method for measuring limb volume is improved by adding ethanol to water. METHODS: Four solutions were tested (pure water, 0.5% ethanol, 3% ethanol, and 6% ethanol) to determine the most accurate method when measuring the volume of a known object. RESULTS: The 3% and 6% ethanol solutions significantly reduced (P < 0.001) the mean standard deviation of 10 measurements of a known sphere (390.1 +/- 0.25 mi) from 2.27 ml with pure water to 0.9 ml using the 3% alcohol solution and to 0.6 using 6% ethanol solution (the mean coefficients of variation were reduced from 0.59% for water to 0.22% for 3% ethanol and 0.16% for 6% ethanol). The spheres' volume measured with pure water, 0.5% ethanol solution, 3% ethanol solution, and 6% ethanol solution was 383.2 +/- 2.27 ml, 384.4 +/- 1.9 ml, 389.4 +/- 0.9 ml, and 390.2 +/- 0.6 ml, respectively. Using the 3% and 6% ethanol solutions to measure hand volume blindly in 10 volunteers significantly reduced the mean coefficient of variation for hand volumetry from 0.91% for water to 0.52% for the 3% ethanol solution (P < 0.05) and to 0.46% for the 6% ethanol solution (P < 0.05). The mean standard deviation from all 10 subjects decreased from 4.2 ml for water to 2.3 ml for 3% ethanol solution and 2.1 ml for the 6% solution. DISCUSSION: These findings document that the accuracy and reproducibility of hand volume measurements are improved by small additions of ethanol, most likely by reducing surface tension of water.


Assuntos
Antropometria/métodos , Etanol , Mãos/anatomia & histologia , Água , Adulto , Humanos , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Soluções
5.
Diabetes Care ; 36(10): 3328-32, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23846813

RESUMO

OBJECTIVE: To investigate the risk of acute myocardial infarction (AMI) following stress hyperglycemia after hip fracture. RESEARCH DESIGN AND METHODS: From February 2007 to February 2012, we carried out a prospective observational analysis of 1,257 consecutive patients with no history of diabetes who suffered hip fractures. Fasting blood glucose (FBG) and glycosylated hemoglobin tests as well as electrocardiography, ultrasonic cardiography, and chest X-ray examinations were performed after admission. All selected hip fracture patients were divided into stress hyperglycemia and non-hyperglycemia groups according to their FBG, and the incidence of AMI was monitored. RESULTS: Among the patients enrolled, the frequency of stress hyperglycemia was 47.89% (602/1,257) and that of AMI was 9.31% (117/1,257), and the occurrence of AMI in the stress hyperglycemia group was higher than in the non-hyperglycemia group (12.46 vs. 6.41%, P<0.05). In the stress hyperglycemia patients, FBG reached maximum levels at 2-3 days after hip fractures and then decreased gradually. The AMI incidence (62.67% [47/75]) of the stress hyperglycemia group was highest in the initial 3 days after hip fracture, significantly coinciding with the FBG peak time (P<0.05). In all patients with AMI, non-ST-segment elevation myocardial infarction occurred more often than ST-segment elevation myocardial infarction (62.39% [73/117] vs. 37.61% [44/117]). CONCLUSIONS: Stress-induced hyperglycemia after hip fracture increased the risk of AMI.


Assuntos
Fraturas do Quadril/complicações , Hiperglicemia/complicações , Hiperglicemia/etiologia , Infarto do Miocárdio/etiologia , Estresse Fisiológico/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Quadril/metabolismo , Humanos , Hiperglicemia/metabolismo , Masculino , Infarto do Miocárdio/metabolismo , Estudos Prospectivos
6.
J Appl Physiol (1985) ; 102(6): 2274-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17395762

RESUMO

The purpose of this study was to determine whether lower body negative pressure (LBNP) treadmill exercise maintains lumbar spinal compressive properties, curvature, and back muscle strength after 28 days of 6 degrees head-down tilt (HDT) bed rest (BR). We hypothesize that LBNP treadmill exercise will maintain lumbar spine compressibility, lumbar lordosis and back muscle strength after 28 days of 6 degrees HDT bed rest. Fifteen healthy identical twin pairs (14 women and 16 men) participated in this study. One identical twin was randomly assigned to the nonexercise control (Con) group, and their sibling was assigned to the exercise (Ex) group. The lumbar spine was significantly more compressible Post-BR compared with Pre-BR in the Con (P=0.01). Lumbar spine compressibility Post-BR was not significantly different compared with Pre-BR in the Ex group (P=0.89). In both the Con and Ex groups, there were no significant changes Post-BR in lumbar lordosis compared with Pre-BR. Back muscle strength significantly decreased in the Con group Post-BR (P=0.002), whereas in the Ex group back muscle strength was not significantly different from Pre-BR values. A significant increase in lumbar spine compressibility in the Con group suggests that spinal deconditioning to gravity occurs during 28-day bed rest. Changes in the mechanical properties of the lumbar spine may be an early indicator of lumbar intervertebral disk degeneration. Supine LBNP treadmill exercise provides axial loads to the lumbar spine and may prevent lumbar spine deconditioning associated with HDT bed rest.


Assuntos
Pressão Negativa da Região Corporal Inferior/métodos , Vértebras Lombares/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Gêmeos Monozigóticos/fisiologia , Suporte de Carga/fisiologia , Ausência de Peso , Adulto , Força Compressiva , Elasticidade , Feminino , Humanos , Masculino , Esforço Físico/fisiologia
7.
J Appl Physiol (1985) ; 99(1): 39-44, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15761083

RESUMO

Astronauts experience spine deconditioning during exposure to microgravity due to the lack of axial loads on the spine. Treadmill exercise in a lower body negative pressure (LBNP) chamber provides axial loads on the lumbar spine. We hypothesize that daily supine LBNP exercise helps counteract lumbar spine deconditioning during 28 days of microgravity simulated by bed rest. Twelve sets of healthy, identical twins underwent 6 degrees head-down-tilt bed rest for 28 days. One subject from each set of twins was randomly assigned to the exercise (Ex) group, whereas their sibling served as a nonexercise control (Con). The Ex group exercised in supine posture within a LBNP chamber for 45 min/day, 6 days/wk. All subjects underwent magnetic resonance imaging of their lumbar spine before and at the end of bed rest. Lumbar spinal length increased 3.7 +/- 0.5 mm in the Con group over 28-day bed rest, whereas, in the Ex group, lumbar spinal length increased significantly less (2.3 +/- 0.4 mm, P = 0.01). All lumbar intervertebral disk heights (L5-S1, L4-5, L3-4, L2-3, and L1-2) in the Con group increased significantly over the 28-day bed rest (P < 0.05). In the Ex group, there were no significant increases in L5-S1 and L4-5 disk heights. Lumbar lordosis decreased significantly by 3.3 +/- 1.2 degrees during bed rest in the Con group (P = 0.02), but it did not decrease significantly in the Ex group. Our results suggest that supine LBNP treadmill exercise partially counteracts lumbar spine lengthening and deconditioning associated with simulated microgravity.


Assuntos
Terapia por Exercício/métodos , Pressão Negativa da Região Corporal Inferior/métodos , Vértebras Lombares/fisiopatologia , Curvaturas da Coluna Vertebral/prevenção & controle , Curvaturas da Coluna Vertebral/fisiopatologia , Suporte de Carga , Simulação de Ausência de Peso/efeitos adversos , Adaptação Fisiológica , Adulto , Repouso em Cama/efeitos adversos , Exercício Físico , Feminino , Humanos , Vértebras Lombares/patologia , Masculino , Curvaturas da Coluna Vertebral/etiologia , Curvaturas da Coluna Vertebral/patologia , Resultado do Tratamento , Gêmeos Monozigóticos
8.
J Acoust Soc Am ; 117(2): 646-52, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15759685

RESUMO

An interferometric technique capable of accurately measuring wave speed in liquids is reported. The hardware is adapted from a design to measure nonlinear responses of biological tissues to pressure changes (pressure derivatives) and temperature changes (temperature derivatives). It is used with the highly sensitive variable frequency pulsed phase-locked loop (VFPPLL) instrument. The system uses well-understood and well-characterized components and systems. The apparatus covers a temperature range from below 5 degrees C to above 45 degrees C. The system with the high-sensitivity VFPPLL is capable of measurement of wave speed to an uncertainty of less than 0.1%, and changes in wave speed to better than 0.001%. The transducer is an undamped temperature-characterized PZT-5A 500-kHz plate, whose output is corrected for off-resonance operation and for diffraction effects. To test the accuracy of the technique, measurement of ultrasonic compressional wave speed in water at temperatures from 10 degrees C to 45 degrees C are reported, with an estimated uncertainty of 0.07% and a temperature uncertainty of 0.15 degrees C. The agreement between mean values and literature values is better than 0.05%.


Assuntos
Reologia , Temperatura , Ultrassonografia , Água , Acústica , Humanos , Oscilometria , Processamento de Sinais Assistido por Computador , Transdutores
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