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From the aerial parts of <i>Senecio dianthus</i>, four new eremophilenolides (<b>1</b>-<b>4</b>, resp.) and one new eremophilenolide alkaloid (<b>5</b>), of the relatively uncommon eremophilenoid-type sesquiterpenoid lactones, were isolated together with three known sesquiterpenoid lactones, 10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>6</b>), 8<i>β</i>,10<i>β</i>-dihydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>7</b>), and 10<i>α</i>-hydroxy-1-oxoeremophila-7(11),8(9)-dien-12,8-olide (<b>8</b>). On the basis of IR, MS, and NMR data, particularly 2D-NMR analyses, the structures of the new compounds were established as: 2<i>β</i>-(angeloyloxy)-10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>1</b>), 6<i>β</i>-(angeloyloxy)-10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>2</b>), 2<i>β</i>-(angeloyloxy)-8<i>β</i>,10<i>β</i>-dihydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>3</b>), 2<i>β</i>-(angeloyloxy)-8<i>α</i>-hydroxyeremophila-7(11),9(10)-dien-12,8<i>β</i>-olide (<b>4</b>), and 8<i>β</i>-amino-10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>5</b>). In addition, the relative configuration of <b>1</b> was corroborated by X-ray diffraction analysis.

A new fluorescent labeling reagent has been developed for the determination of fatty acids (FAs) by HPLC with fluorescence detection. The derivatization conditions including the amount of derivatization reagent, temperature, and type of catalyst were investigated, the results indicated that the reaction proceeded within 30 min at 90°C in the presence of K₂CO₃ catalyst. The maximal yield was obtained with a four- to fivefold molar reagent excess. The derivatives exhibited strong fluorescence with an excitation maximum at <i>λ</i><sub>ex</sub> = 245 nm and an emission maximum at <i>λ</i><sub>em</sub> = 410 nm. Twenty-five FA derivatives were well separated by RP-HPLC on a Hypersil BDS C₈ column in combination with gradient elution. All FAs were found to give excellent linear responses with correlation coefficients >0.9992. The method gave a low LOQ of 0.85-5.5 ng/mL (S/N of 10). The developed method was employed to analyze free FAs (FFAs) composition in pomegranate samples without any purification. FFAs in samples were doubly identified by HPLC retention time and protonated molecular ion corresponding to <i>m</i>/<i>z</i> [M+H]⁺. This newly developed method allows a highly sensitive determination of trace FFAs from pomegranate and other foodstuffs.

A new isocoumarin, along with 10 known compounds, was isolated from the aerial parts of Aconitum gymnandrum. Their structures were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Among the known compounds, compound 11 was obtained as a natural product for the first time, which was previously reported as a synthetic product. In addition, compounds 1-5, 7 and 9 were tested for their cytotoxicity against four human cancer cell lines. The results showed that compounds 3, 4 and 7 displayed cytotoxicity against lung cancer A549 and gastric cancer MGC80, respectively, whereas 5 and 9 showed selective cytotoxicity against hepatocellular carcinoma HepG2.

OBJECTIVE: To establish a simple, rapid and usable new method of processing on Rhei Radix Et Rhizoma and the quality control standard on its processing products.METHODS: The studies of processing on Rhei Radix Et Rhizoma were proceed using yellow rice wine as solvent, through spray, soften and dry at 60-70 degrees C. The contents of total and uncombined chrysophanol and emodin in multi-Rhei Radix Et Rhizoma and its processing products were determined by HPLC. RESULTS: The new method of processing on Rhei Radix Et Rhizoma was simple, rapid and usable. The contents of uncombined chrysophanol and emodin in its processing products was 80%. CONCLUSION: This study provides a new method of processing on Rhei Radix Et Rhizoma and quality control standard on its processing products.

<br>Display Omitted<br>• Two new monoterpenes named sibiscolactons A and B (<b>1</b> and <b>2</b>) were isolated from <b>Sibiraea laevigata</b>. • New compounds’ absolute configurations were established by electronic circular dichroism (ECD) calculations. • Eight known phenylpropanoids (<b>3</b>-<b>10</b>) were also obtained from the title plant. • <b>1</b>-<b>10</b> were evaluated for their cytotoxic activity. • Compound <b>3</b> displayed moderate cytotoxicity with IC50 values ranging from 10.8 to 49.2 μg mL−1.<br>Chemical investigation of the ethanol extract of the stalks and infructescence of <b>Sibiraea leavigata</b> led to the isolation of two new monoterpenes named (4<b>R</b>)-2-(2-hydroxy-4-methyl-3-pentenyl)furan-2(5<b>H</b>)-one (<b>1</b>) and (2<b>R</b>,4<b>R</b>)-2-(2-hydroxyethyl)-4-(2-methyl-1-propenyl)furan-5<b>H</b>-2-one (<b>2</b>) along with eight known phenylpropanoids (<b>3-10</b>). Their structures were established on the basis of the interpretation of spectroscopic data and electronic circular dichroism (ECD) calculations. In addition, all of these isolates were evaluated for their cytotoxic activity. The results showed that compound <b>3</b> displayed moderate cytotoxicity with IC50 values ranging from 10.8 to 49.2 μg mL−1 against five cell lines. While <b>1</b> showed selective promotion effects on proliferation of gastric cancer MGC803 and RSC96 cell lines.

Phytochemical investigation on <b>Asterothamnus centrali-asiaticus</b> afforded four new sesquiterpenes, asterothamnones A-D (<b>1</b>-<b>4</b>), and three new benzofuran derivatives (<b>5</b>-<b>7</b>) together with ten known compounds (<b>8</b>-<b>17</b>). Their structures were elucidated using 1D and 2D NMR and X-ray diffraction analyses. Compounds <b>1</b>-<b>4</b> were verified to be unusual eudesmane sesquiterpenes possessing 4,6-dien-3-one or 1,4,6-triene-3-one conjugated system. The absolute configurations of compounds <b>1</b>-<b>8</b> were established by means of calculated electronic circular dichroism (ECD). Furthermore, all isolates were evaluated for their cytotoxic and anti-oxidant activities. Results showed that <b>10</b>, <b>12</b> and, <b>14</b> exhibited cytotoxic activity against HepG2 cancer cells and <b>14</b> displayed cytotoxicity against MGC-803 cancer cells. Compounds <b>10</b> and <b>17</b> showed anti-oxidant effect.<br><br>Display Omitted

"RenqingMangjue" pill (RMP), as an effective prescription of Traditional Tibetan Medicine (TTM), has been widely used in treating digestive diseases and ulcerative colitis for over a thousand years. In certain classical Tibetan Medicine, heavy metal may add as an active ingredient, but it may cause contamination unintentionally in some cases. Therefore, the toxicity and adverse effects of TTM became to draw public attention. In this study, 48 male Wistar rats were orally administrated with different dosages of RMP once a day for 15 consecutive days, then half of the rats were euthanized on the 15th day and the remaining were euthanized on the 30th day. Plasma, kidney and liver samples were acquired to 1H NMR metabolomics analysis. Histopathology and ICP-MS were applied to support the metabolomics findings. The metabolic signature of plasma from RMP-administrated rats exhibited increasing levels of glucose, betaine, and creatine, together with decreasing levels of lipids, 3-hydroxybutate, pyruvate, citrate, valine, leucine, isoleucine, glutamate, and glutamine. The metabolomics analysis results of liver showed that after RMP administration, the concentrations of valine, leucine, proline, tyrosine, and tryptophan elevated, while glucose, sarcosine and 3-hydroxybutyrate decreased. The levels of metabolites in kidney, such as, leucine, valine, isoleucine and tyrosine, were increased, while taurine, glutamate, and glutamine decreased. The study provides several potential biomarkers for the toxicity mechanism research of RMP and shows that RMP may cause injury in kidney and liver and disturbance of several pathways, such as energy metabolism, oxidative stress, glucose and amino acids metabolism.

OBJECTIVE: To study the chemical constituents of a Tibetan medicine Meconopsis quintuplinervia.METHOD: Column chromatographic techniques were applied to isolate constituents. A combination of IR, MS and NMR spectroscopy was used to identify structures of constituents. RESULT: Twelve compounds were isolated from the ethanolic extract and their structures were elucidated as quercetin 3-O-beta-D-glucopyranoside (I), quercetin 3-O-beta-D-galactopyranosyl-(1-->6)-glucopyranoside (II), kaempferol 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside (III), isorhamnetin 3-0-beta-D-galactopyranosyl-(1-->6)-beta-D-glucopyranoside (IV), caffeic acid (V), protocatechuic acid (VI), p-hydroxycinnamic (VII), 2-(3,4-dihydroxyphenyl )-ethyl-O-beta-D-glucopyranoside (VIII), p-hydroxybenzoyl-beta-D-glucopyranoside (IX), 4-O-beta-D-glucopyranosyl-(Z)-p-coumaric acid (X), 5, 7-dihydroxy-4H-4-chromenone (XI), daucosterol (XII). CONCLUSION: Ten compounds were isolated from this genus for the first time except for XI and XII.

<P>Nitrogen (N) availability is a key regulator of carbon (C) cycling in terrestrial ecosystems. Anthropogenic N input, such as N deposition and fertilization, increases N availability in soil, which has important implications for an ecosystem’s C storage and loss. Soil respiration (Rs), which is the second largest C flux from terrestrial ecosystems to the atmosphere, plays an important role in terrestrial C cycles. The direction and magnitude of the responses of Rs and its components to N addition have been widely evaluated, but it remains unclear how these processes change across multiple N addition levels. Here we conducted a two-year field experiment to examine the changes of Rs and its autotrophic respiration (Ra) and heterotrophic respiration (Rh) components along a gradient of eight N levels (0, 1 2, 4, 8, 16, 24, 32 g m<SUP>−2</SUP> yr<SUP>−1</SUP>) in a Tibetan alpine steppe, and used structural equation modeling (SEM) to explore the relative contributions of biotic and abiotic variables and their direct and indirect pathways regulating the Ra and Rh. Our results indicated that both Rs and Ra exhibited first increasing and then subsequent decreasing trends at the threshold of 8 g N m<SUP>−2</SUP> yr<SUP>−1</SUP>. In contrast, the Rh declined linearly with the N addition rate continuously increasing. SEM analysis revealed that, among various environmental factors, soil temperature was the most important one modulating Rs, which not only had a direct effect on the two Rs components, but also indirectly regulated the Ra and Rh via root and microbial biomass. These findings suggest that the nonlinear response patterns of Rs should be considered for better predicting terrestrial C balance, given that anthropogenic N input to the terrestrial ecosystems is increasing continuously.</P>

Dried herb of Delphinium brunonianum Royle (Ranunculaceae) has long been used under the herbal name "Xiaguobei" (Delphinii Brunoniani Herba) in traditional Tibetan medicine and prescribed for the treatment of influenza, itchy skin rash and snake bites. In order to find a useful and convenient method for the identification of microscopic features, the technique of fluorescence microscopy was applied to authenticate "Xiaguobei" of Tibet. The transverse sections of stem and leaf, as well as the powder of "Xiaguobei" were observed to seek for typical microscopic features by normal light and fluorescence microscopy. A style-like, single-cell glandular hair containing yellow secretions on the leaf, young stem and sepal of "Xiaguobei" was found. Under the fluorescence microscope, the xylem and pericycle fiber group emitted significant fluorescence. This work indicated that fluorescence microscopy could be an useful additional method for the authentication work. Without the traditional dyeing methods, the main microscopic features could be easily found by fluorescence microscopy. The results provided reliable references for the authentication of "Xiaguobei".

The goal of the presented work is to develop a simple and sensitive high-performance liquid chromatography in combination with fluorescence detection (HPLC-FLD) method for the determination of four nitrofurans (NFs) metabolites compounds (semicarbazide (SEM), 1-aminohydantoin (AH), 3-amino-2-oxazolidinone (AOZ) and 3-amino-morpholinomethyl-2-oxazolidinone (AMOZ)) in foodstuffs. For this goal, we synthesized a novel fluorescence labeling reagent, 4-(carbazole-9-yl)-benzyl chloroformate (CBBC) to label NFs metabolites compounds. NFs metabolites compounds can be labeled rapidly only within 5 min at the room temperature (25 °C). The labeled derivatives showed excellent fluorescence property with maximum excitation and emission wavelengths of 375 nm and 410 nm, respectively. The labeled derivatives were analyzed on a reversed-phase Eclipse XDB-C18 column within 10 min. Excellent linearity (R2 > 0.995) of all NFs metabolites compounds was achieved with the limits of detection (LODs) and the limits of quantitations (LOQs) in the low micrograms per kilogram range of 0.20-0.30 μg·kg−1 and 0.70-1.00 μg·kg−1, respectively. Satisfactory recoveries in the range of 92.5-98.0% were obtained for all NFs metabolites compounds. Using the proposed HPLC-FLD method, we successfully determined four NFs metabolites compounds in different foodstuffs. As promising, this highly sensitive and reliable method would also be extended for the quantitation of NFs metabolites compounds in other samples.<br><br>Display Omitted<br>• A novel fluorescence labeling reagent CBBC was synthesized to label nitrofurans (NFs) metabolites compounds. • A pre-column derivatization HPLC-FLD method was developed for the determination of NFs metabolites compounds in foodstuffs. • LODs were in the low micrograms per kilogram range of 0.2-0.3 μg·kg-1.

A stable, effective, sensitive and selective method for simultaneous determination of 11 aldehydes in foodstuffs using a novel fluorescence-labeling reagent 2-(12-benzo[<i>b</i>]acridin-5-(12<i>H</i>)-yl)-acetohydrazide (BAAH) has been developed by HPLC with fluorescence detection and mass spectrometric identification. Response surface methodology was employed to optimize the derivatization reaction between BAAH and aldehydes. The completed separation of the 11 aldehydes was achieved in as little as 18 min on a reversed-phase Hypersil BDS C<sub>8</sub> column with aqueous acetonitrile as mobile phase in conjunction with a binary gradient elution. Excellent linear coefficients were found to be of >0.9994. This method also showed excellent reproducibility and offered the low detection limits of 0.21-0.58 nM (at a signal-to-noise ratio of 3). The developed method was successfully applied to analyze aldehydes in various foodstuffs and exhibited satisfactory applicability.

<br>Display Omitted<br>• Conversion of waste buckthorn branches to a value-added bio-carbon product. • Practical adsorbent for removal and destruction of DC contaminants. • Consecutive biosorption and heterogeneous Fenton oxidation regeneration cycles. • Composite biosorbent with β-FeOOH nanoparticles and in-situ catalytic regeneration properties.<br>Akaganeite (β-FeOOH) nanoparticles were successfully anchored on the surface of porous sea buckthorn biocarbon (SBC) via a simple low-temperature hydrothermal process without use of surfactants or external forces. The SBC@β-FeOOH composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). On the basis of characterization methods, a possible mechanism of formation of the SBC@β-FeOOH composite was discussed. The SBC@β-FeOOH composite was used in fixed-bed columns for the effective removal of doxycycline (DC) from an aqueous solution, by the synergistic effect of adsorption and subsequent Fenton-like oxidation reaction, which oxidized the sorbed DC. The effects of inlet DC concentration (22-32 mg/L) feed flow rate (1-3 mL/min) SBC@β-FeOOH bed depth (0.7-1.5 cm) and pH (2-11) on the adsorption breakthrough profiles were investigated. The adsorption process was controlled by the ionic speciation of the adsorbate DC and the available binding sites of SBC@β-FeOOH. It was simulated by the Thomas and Yoon-Nelson models under different conditions. The bed of SBC@β-FeOOH saturated with DC was readily regenerated, in situ, by a heterogeneous Fenton-like oxidation reaction. The synergistic effect resulting from the biosorption nature of SBC and the catalytic oxidation properties of the supported β-FeOOH nanoparticles results in a new promising composite material for water treatment and purification.

BACKGROUND: Nursing students face a great amount of psychological stress during their nursing education. Mindfulness-based training has received increased recognition from nurse educators regarding its effect on reducing students' psychological stress. Study evidence has supported that cultivation of trait mindfulness through Mindfulness-based training was the key to this effect. However, there is a lack of research that focuses on intricate relationships between various facets of trait mindfulness and psychological stress.OBJECTIVE: Examining the relationships between various trait mindfulness facets and psychological stress. DESIGN: A cross-sectional design was used to collect data on trait mindfulness facets and psychological stress. PARTICIPANTS: A convenience sample of 99 undergraduate nursing students from a Bachelor of Nursing program completed this study. SETTING: This study was conducted in a university in the south-eastern United States. METHOD: Participants completed an online questionnaire, which collected their demographic information, trait mindfulness (the Five Factor Mindfulness Questionnaire), and psychological stress (the Perceived Stress Scale-10). Correlation and mediation analyses were applied. RESULTS: Other than the trait mindfulness facet of observing, the remaining three facets (acting with awareness, non-judging, and non-reactivity) were negatively correlated with psychological stress. Observing had little to low correlations with non-judging and acting with awareness, but attained a moderately positive correlation with non-reactivity. Moreover, observing could indirectly predict psychological stress, when non-reactivity served as a mediator. Finally, non-judging partially mediated the relationship between acting with awareness and psychological stress. CONCLUSIONS: The results of the current study can help nurse educators better understand the intricate relationships between various facets of trait mindfulness and psychological stress. Specifically, facets of acting with awareness, non-judging, and non-reactivity are directly relevant to the reduction of psychological stress. Therefore, regardless of formal or informal practices of mindfulness, nurse educators ought to assist students in cultivating these facets as means toward stress management.

A new iridoid named (1R,6S,8R,9R) -1 -ethoxy-8-methyl-1,5,6,7,8,9-hexahydrocyclopenta[c] pyran-4-carbaldehyde (1) was isolated from the Tibetan folk medicine Incarvillea younghusbandii Sprague. Its structure was elucidated by spectral methods,e, g. ID and 2D NMR and HRMS.

High-speed counter-current chromatography (HSCCC) was successfully applied to the isolation and purification of four xanthone glycosides from Halenia elliptica, a plant widely used in traditional Tibetan medicine. The introduction of HSCCC greatly improved the efficiency of compounds preparation from Halenia elliptica. The following were obtained from 100 mg of crude sample in one-step separation: 2.5 mg of 1-O-primeverosyl-2,3,4,5,7-pentamethoxyxanthone, 7.0 mg of 1-O-primeverosyl-2,3,4,7- tetramethoxyxanthone, 10.0 mg of 1-O-primeverosyl-2,3,5-trimethoxyxanthone (demethyoxyhaleniaside), and 8.5 mg of 1-O-primeverosyl-2,3,4,5-tetramethoxyxanthone. HPLC analysis showed that each target compound had a purity of over 98%, and UV, 1H NMR, and 13C NMR data confirmed the component chemical structures.

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5 : 2.5 : 3 : 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by (1)H-NMR and (13)C-NMR data.

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5 : 2.5 : 3 : 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by (1)H-NMR and (13)C-NMR data.

The purpose of this study was to investigate whether EEG biofeedback would help engage learners in obtaining procedural knowledge from animated or static visualizations. Two specific forms of this feedback were investigated. The first was active feedback that required learners to interact with the feedback using hand gestures. The second was constructive feedback that instructed learners to verbally reflect on their learning processes by utilizing the feedback. A total of 116 college students were randomly assigned to one of six experimental conditions formed by a 2 X 3 factorial design with the visualization type (animated vs. static) as one factor and the feedback type as the other factor (constructive vs. active vs. no feedback). The results revealed that learners who received no feedback had significantly higher perceived attentiveness and value than their peers who received constructive feedback. Additionally, when constructive feedback was provided, learning procedural knowledge from animated visualizations reduced perceived difficulty in learners when compared to static visualizations. These findings were discussed in terms of the implications, limitations, and future research directions.

Generally, it is claimed that gestation theory was originated locally in Tibet, with only a single origin. This author proves that there are two sources, both derived from India. One is a combination of gestation theory from rGyud-bzhi, i.e. Astangahrdayasamhita, and the Great Ratnakuta, and the other, from Somaradza, also derived from the Great Ratnakuta. The dates of writing of modern edition of Somaradza and rGyud-bzhi are still uncertain yet. Based on the linguistic features, this author claims that Somaradza was written before the Tibetan version of Great Ratnakuta (9 century), while rGyud-bzhi, after the translation of Astangahrdayasamhita (10-11 century).

Background The receptor for advanced glycation endproducts (RAGE) is an oncogenic multidisciplinary trans-membranous receptor, which is overexpressed in multiple human cancers. Recently, it has been shown that RAGE is also involved in carcinogenesis and tumor invasion. In this study, we investigated the expression levels and prognostic value of RAGE in primary gastric cancers (GC). Methods We investigated RAGE expression in primary GC and paired normal gastric tissue by real-time quantitative RT-PCR (n = 30) and Western blotting analysis (n = 30). Additionally, we performed immunohistochemistry on 180 paraffin-embedded GC specimens, 69 matched normal specimens. Results RAGE was overexpressed in GC compared with the adjacent noncancerous tissues (P<0.001), and higher RAGE expression significantly correlated with the histological grade (P = 0.002), nodal status(P = 0.025), metastasis status(P = 0.002), and American Joint Committee on Cancer stage (P = 0.020). Furthermore, upregulation of RAGE expression is an independent prognostic factor in multivariate analysis using the Cox regression model (P = 0.001). Conclusions RAGE Overexpression may be a useful marker to predict GC progression and poor prognosis.

"Zuotai" is one of the main raw material of many rare Tibetan medicine, and it plays a important role in the system of Tibetan medicine. There are some toxic heavy metals in "Zuotai", such as Hg, Au, Pb and so on. As a result, it's urgent to study the safety and effectiveness of "Zuotai" in depth. This paper will analyze and induce the resent progress of the study about "Zuotai". With constipation, "Zuotai" and "Zuotai" as key words, CNKI, CHINAINFO, CQVIP were retrieved, Springer were retrieved besides. Relevant 86 references were obtained. Twenty-two for reference were adopted through screening. The paper reviewed the resent progress of the study about "Zuotai" in chemical composition, pharmacodynamics and pharmacokinetics, toxicology and clinical application. This will establish the basis for further study.

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