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<br>Display Omitted<br>• The effect of organic sample solvents in SCX mode were systematically studied. • Organic sample solvents affect the separation efficiency in SCX mode seriously. • Elution strength of organic solvents affect efficiency of later-eluted analyte. • Retention of organic solvents affected efficiency of earlier-eluted analyte. • The results can be used for the optimization of SCX methods.<br>This study investigated the influence of organic sample solvents on separation efficiency of basic compounds under strong cation exchange (SCX) mode. The mixtures of acidic aqueous solution and organic solvent such as acetonitrile, ethanol, methanol and dimethyl sulfoxide (DMSO) were tested as sample solvents. For later-eluting analytes, the increase of sample solvent elution strength was responsible for the decrease of separation efficiency. Thus, sample solvents with weak elution strength could provide high separation efficiencies. For earlier-eluting analytes, the retention of organic sample solvents was the main factor affecting separation efficiency. Weakly retained solvents could provide high separation efficiency. In addition, an optimized approach was proposed to reduce the effect of organic sample solvent, in which low ionic solvent was employed as initial mobile phase in the gradient. At last, the analysis of impurities in hydrophobic drug berberine was performed. The results showed that using acidic aqueous methanol as sample solvents could provide high separation efficiency and good resolution (<b>R</b> > 1.5).

Nitraria tangutorum Bor., having edible berries, is valued for reputed health benefits in Qinghai-Tibet plateau. The phytochemical research on the fruit juice of N. tangutorum led to the isolation of twenty-six compounds including five new compounds, tangutorids A-D (1, 2, 3a, and 3b), and (3E,5E)-7-O-β-glucosyl-4-(2-methoxy-2-oxoethyl)hepta-3,5-dienoic acid (15). The structures of these compounds were elucidated through comprehensive spectroscopic analyses. Tangutorids A-F were the first examples of glucose-derived β-carbolines from natural products. The biogenetic pathways of 1-8 were proposed to involve Pictet-Spengler reactions and described starting from the co-isolated tryptophan (10) and corresponding aldehydes. All isolates were evaluated for their antioxidant and α-glucosidase inhibitory activities. Compounds 21, 22, and 24 showed antioxidant activity with SC50 values ranging from 12.2±1.9 to 30.4±2.7μg/mL, and compound 1 showed strong α-glucosidase inhibitory effect with IC50 value of 63.3±4.6μg/mL.

Based on literature data, related specimens, commercial samples and field investigation, botanical origin of "bolingguazi" was clarified. Boling guazi was found to be used as a Tibetan medicine in China from 8th century, it was derived from Herpetospermum pedunculosum of cucurbitaceae, and main species of bolingguazi used in most areas of China were H. pednculosura, while seeds of Momordica charantia, Thladiantha setispina and M. cohinchinensis were also available in some areas of China.

BACKGROUND: Medicinal plants used by the local people in Xizang (Tibet) have been investigated since the 1960s. The others out of Xizang, however, have been less understood, although they may be easily and strongly influenced by the various local herbal practices, diverse environments, local religious beliefs and different prevalent types of diseases. In 2006, two ethnobotanical surveys were organized in the county of Shangri-la, Yunnan Province, SW China, to document the traditional medicinal plants used by the Tibetan people.METHODS: After literature surveying, four local townships were selected to carry out the field investigation. Three local healers were interviewed as key informants. The methods of ethnobotany, anthropology and participatory rural appraisal (PRA) were used in the field surveys. Plant taxonomic approach was adopted for voucher specimen identification. RESULTS: Sixty-eight medicinal plant species in 64 genera of 40 families were recorded and collected. Among them, 23 species were found to have medicinal values that have not been recorded in any existing Tibetan literatures before, and 31 species were recorded to have traditional prescriptions. Moreover, the traditional preparations of each species and some folk medicinal knowledge were recorded and analyzed. These traditional prescriptions, preparations, new medicinal plants and folk medicinal knowledge and principles were discovered and summarized by local traditional Tibetan healers through times of treatment practices, and were passed down from generation to generation. CONCLUSION: As a part of the cultural diversity of Tibetan community, these traditional medicinal knowledge and experiences may provide data and information basis for the sustainable utilization and development of Tibetan medicine, and may contribute to the local economic development. However, for many reasons, they are disappearing gradually as time goes by. Our study showed that there were abundant traditional Tibetan medicinal prescriptions and using methods. It implies that more Tibetan medicinal plants and traditional knowledge can be discovered. Further research should be done to save the wealth of these traditional medicinal knowledge and experiences before they are dying out.

We investigate the role of mindfulness as a regulatory factor by examining whether it mitigates the relationship between justice and retaliation. Drawing on theories of self-regulation, we integrate work on justice with emerging frameworks that identify mindfulness as an important work-related regulatory variable (Glomb, Duffy, Bono, & Yang, 2011). Specifically, we identify the role of mindfulness as a buffer of the ruminative thoughts and negative emotions that link injustice to retaliation. We test mediated moderation hypotheses in 2 samples. In Sample 1, two behavioral measures of retaliation are assessed in an experiment that manipulated both injustice and mindfulness. In Sample 2, we generalize our model to the field, examining employee responses regarding experiences with workplace injustice and retaliation. Results of both studies converge to support the proposed mediated moderation model that mindfulness buffers the effect of injustice on rumination and negative emotions, thus reducing retaliation. Our findings contribute to the broader literatures on self-regulation, organizational justice, and retaliation.

We investigate the role of mindfulness as a regulatory factor by examining whether it mitigates the relationship between justice and retaliation. Drawing on theories of self-regulation, we integrate work on justice with emerging frameworks that identify mindfulness as an important work-related regulatory variable (Glomb, Duffy, Bono, & Yang, 2011). Specifically, we identify the role of mindfulness as a buffer of the ruminative thoughts and negative emotions that link injustice to retaliation. We test mediated moderation hypotheses in 2 samples. In Sample 1, two behavioral measures of retaliation are assessed in an experiment that manipulated both injustice and mindfulness. In Sample 2, we generalize our model to the field, examining employee responses regarding experiences with workplace injustice and retaliation. Results of both studies converge to support the proposed mediated moderation model that mindfulness buffers the effect of injustice on rumination and negative emotions, thus reducing retaliation. Our findings contribute to the broader literatures on self-regulation, organizational justice, and retaliation.

High-speed counter-current chromatography (HSCCC) was successfully applied for the first time to isolate and purify four cis-trans isomers of coumaroylspermidine analogs from Safflower. HSCCC separation was achieved with a two-phase solvent system composed of chloroform-methanol-water (1:1:1, v/v/v) with the upper phase as the mobile phase. In a single run, a total of 1.3mg of N(1), N(5), N(10)-(E)-tri-p-coumaroylspermidine (EEE), 4.4mg of N(1)(E)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (EZE), 7.2mg of N(1)(Z)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (ZZE), and 11.5mg of N(1),N(5),N(10)-(Z)-tri-p-coumaroylspermidine (ZZZ) were obtained from 100mg of crude sample. High Performance Liquid Chromatography (HPLC) analysis showed that the purities of these four components are 95.5%, 98.1%, 97.5% and 96.2%, respectively. The chemical structures were identified by ESI-MS, (1)H NMR and (13)C NMR.

A reversed-phase high-performance liquid chromatographic method with diode array detection was established to simultaneously determine the seven bioactive lignans in <i>Herpetospermum caudigerum</i>, namely ent-isolariciresinol (<b>1</b>), dehydrodiconiferyl alcohol (<b>2</b>), herpetrione (<b>3</b>), herpetin (<b>4</b>), herpetetrone (<b>5</b>), herpetotriol (<b>6</b>) amd herpetal (<b>7</b>). The HPLC assay was performed on a Restek Pinnacle DB C<sub>18</sub> column (250 × 4.6 mm, 5 µm) with gradient elution of acetonitrile and 0.1% phosphoric acid within 65 min. The detection wavelength was 240 nm. The flow-rate was 1.0 mL/min. All calibration curves showed good linearity (<i>r</i>² > 0.9998) within test ranges. The method was reproducible with intra- and inter-day variation of less than 1.98%. The method provided good accuracy with recoveries in the range 95.19-102.64% with RSDs less than 1.52%. The method was successfully applied to the quantification of seven constituents in 15 <i>H. caudigerum</i> samples collected from different cities. The results indicated that the developed assay could be considered as a suitable quality control method for <i>H. caudigerum</i>. Copyright © 2008 John Wiley & Sons, Ltd.

A chemometrics-assisted excitation-emission matrix (EEM) fluorescence method is presented for simultaneous determination of umbelliferone and scopoletin in Tibetan medicine Saussurea laniceps (SL) and traditional Chinese medicine Radix angelicae pubescentis (RAP). Using the strategy of combining EEM fluorescence data with second-order calibration method based on the alternating trilinear decomposition (ATLD) algorithm, the simultaneous quantification of umbelliferone and scopoletin in the two different complex systems was achieved successfully, even in the presence of potential interferents. The pretreatment is simple due to the "second-order advantage" and the use of "mathematical separation" instead of awkward "physical or chemical separation". Satisfactory results have been achieved with the limits of detection (LODs) of umbelliferone and scopoletin being 0.06ngmL(-1) and 0.16ngmL(-1), respectively. The average spike recoveries of umbelliferone and scopoletin are 98.8±4.3% and 102.5±3.3%, respectively. Besides, HPLC-DAD method was used to further validate the presented strategy, and t-test indicates that prediction results of the two methods have no significant differences. Satisfactory experimental results imply that our method is fast, low-cost and sensitive when compared with HPLC-DAD method.

To evaluate the efficacy and safety associated with anti-hypoxia effect and establish the quality standard for Brassicea Radix extract, the investigations of acute toxicity and subacute toxicity were carried out to preliminarily appraise the toxicity, and the models of normal pressure hypoxia, acute cerebral ischemia and sodium nitrite poisoning in mice were used to evaluate the effect of enhancing anoxia endurance. Then according to the methods described in the Appendix of Chinese Pharmacopoeia (2010 edition), the sulfuric acid-phenol method was applied to determine the content of polysaccharide, and the water, ash and insoluble matter in water inspections were carried out and the control medicinal herb was identified with the samples by qualitative TLC. The results indicated that ① the toxic effects (LD₅₀) of mice was 56.73 g•kg⁻¹ by oral administration of Brassicea Radix extract, while Dm and Dn were respective 86.80 g•kg•d⁻¹ and 35.55 g•kg•d⁻¹;②the determined effective dosage of Brassicea Radix extract which could enhance anoxia endurance was 0.388 g•kg⁻¹•d⁻¹; ③ the methods of TLC and the content of polysaccharide were established. The method of quality control has been recorded in Sichuan Province Standard for Tibetan Medicine, which is reliable, accurate and simple, with good reproducibility. Meanwhile, given the prominent effect on anti-hypoxia and good safety, it provided important basis for clinic safe and effective usage and the development of health products.

Tai Chi Chuan (TCC) practice is currently intentionally applied in clinical populations, especially those with cardiovascular diseases because of its potential benefits on the autonomic nervous system. The long-term effect of TCC practice on heart rate variability (HRV) remains largely unknown. In this study, we recruited 23 TCC practitioners whose experience averaged approximately 21 years and 19 controls matched by age, sex and education to examine the effect of TCC practice on the autonomic nervous system during a resting state and during an abdominal breathing state. HRV was measured by traditional electrocardiogram (ECG) recording. The results showed that the low frequency, total power frequency, and normalized low frequency components and the low-frequency/high-frequency ratio were significantly higher, whereas the normalized high frequency was significantly lower in the TCC practitioners relative to controls during the abdominal breathing state. However, we did not detect any significant difference in the HRV measures during the resting state between the two groups. Additionally, TCC experience did not correlate with HRV components either in the abdominal state or the resting state in the TCC group. Considering all of these findings, we suggest that TCC improves vagal activity and the balance between sympathetic and parasympathetic activity during the relaxation state. This study also provides direct physiological evidence for the role of TCC practice in relaxation.

Three new flavone C-glycosides, paraquinins A-C, were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan medicine distributed in the Qinghai-Tibet plateau. On the basis of 1D and 2D NMR evidence, their structures were elucidated as acacetin-6-C-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (1), acacetin-6-C-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (2), and acacetin-6-C-α-L-rhamnopyranosyl-(1 → 2)-(6'''-O-E-feruloyl)-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (3).

Highly elevated concentrations of total mercury (THg) and methylmercury (MeHg) were found in the municipal sewage in Tibet. Material flow analysis supports the hypothesis that these elevated concentrations are related to regular ingestion of Hg-containing Traditional Tibetan Medicine (TTM). In Tibet in 2015, a total of 3600 kg of THg was released from human body into the terrestrial environment as a result of TTM ingestion, amounting to 45% of the total THg release into the terrestrial environment in Tibet, hence substantially enhancing the environmental Hg burden. Regular ingestion of TTM leads to chronic exposure of Tibetans to inorganic Hg (IHg) and MeHg, which is 34 to 3000-fold and 0-12-fold higher than from any other known dietary sources, respectively. Application of a human physiology model demonstrated that ingestion of TTM can induce high blood IHg and MeHg levels in the human body. Moreover, 180 days would be required for the MeHg to be cleared out of the human body and return to the initial concentration i.e. prior to the ingestion of 1 TTM pill. Our analysis suggests that high Hg level contained in TTM could be harmful to human health and elevate the environmental Hg burden in Tibet.

Teachers are the primary deliverers of Social-Emotional Learning (SEL) program, and therefore their beliefs, attitudes, and support towards SEL influence the adoption, sustainability, and impacts of this program. The aim of the present research is to measure the perception of social emotional learning education among Vietnamese primary school teachers. A group of 250 Vietnamese primary school teachers (142 males and 108 females) participated in the survey. They completed the Teachers' Perceptions of Social Emotional Learning scale (TPSEL). The scale included four subscales which are the Teachers' perceived level of the necessity of SEL education in primary schools (TPN), the Teachers' perceived level of the importance of SEL education in primary schools (TPI), the Teachers' perceived level of concern about SEL education in primary schools (TPC), and the Barriers to the Implementation of SEL Programs (BISEL). Results showed significant differences in BISEL among the teachers with different years of teaching experience. Moreover, various educational backgrounds affected TPN and BISEL considerably. The interation effect on TPN and BISEL was found. The results suggested that regardless of the differences in educational backgrounds and years of experience, the teachers were all aware of the necessity as well as the challenges when implementing SEL in classrooms in primary schools. [ABSTRACT FROM AUTHOR]; Copyright of European Journal of Contemporary Education is the property of European Researcher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Soft tissue injury imposes major public health burdens worldwide. The positive effect of China's Tibetan medicine and the Lamiophlomis rotata-based herbal Pain Relieving Plaster (PRP) on healing closed soft tissue injury (CSTI) has been reported. The herbs contained in Plaster are also referred as 'blood-activating and stasis-dispelling' in herbal medicine. The formula of the plaster contains four China's Tibetan medical herbs, including Lamiophlomis rotata, Oxytropis falcate Bunge, Curcuma longa Linn, and Myricaria bracteata. Two of these herbs (Lamiophlomis rotate; Curcuma longa Linn) are commonly used in different formulae of Chinese medicine. The objective of this study is to use an interdisciplinary approach to test the hypothesis that the formula and its components influence the process of CSTI.METHODS: In vivo models have been established in 30 rabbit ear pinnae and studied for: (1) blood flow velocity (BFV) which was affected by pressure of 21.2 kg/cm2 for 30 second over the local rabbit ear tissue; (2) edema formation of the closed soft tissue injury; (3) in vivo local temperature change. RESULTS: The results of in vivo studies indicated that CSTI significantly increased the velocity of blood flow and increased edema formation within the control group. The PRP extracts for 5 hours significantly slowed down the BFV of CSTI in rabbit ears, markedly decreased the elevated edema level from the 3rd to the 5th day. CONCLUSION: The ingredients contained in the formula have positive effects in healing CSTI and further study is worth exploring.

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