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The young leaves and shoots of Sibiraea laevigata, known as "Liucha", are used as tea by Tibetans to improve digestion after meals. Long-term consumption of "Liucha" will cause weight loss. In present work, we reported on the isolation and NMR and chemical analysis-based elucidation of seven new sorbitol O-caffeic acid ester derivatives named sorbitol esters A-G (1-7) and eighteen known phenolic compounds from S. laevigata. All of the isolates were evaluated for their antioxidant and α-glucosidase inhibitory activities. Among them sorbitol ester A (1), sorbitol ester D (4), sorbitol ester F (6), sorbitol ester G (7), isoferulic acid (15), methyl caffeate (18), trans-p-hydroxycinnamic acid (19), and kaempferol 3-O-β-d-(6″-E-p-coumaroyl)-glucopyranoside (25) showed more potent α-glucosidase inhibitory activity than the clinical drug acarbose.

• <b>Saxifraga tangutica</b> Engl. is a promising source of antioxidants against DPPH and FRAP. • The 50% ethanol extract of S. <b>tangutica</b> showed strong antioxidative activity against DPPH and FRAP. • Eight phenols were isolated from S. <b>tangutica</b>; all of the compounds are reported for the first time from this plant. • The antioxidative S. <b>tangutica</b> extracts and isolated phenols supports the antioxidant of this plant.<br><b>Saxifraga tangutica</b> Engl., is a medicinal herb that grows on the Qinghai-Tibet Plateau. Extracts and phenols from the Qinghai population have been subjected to antioxidative assays against DPPH radical-scavenging and reducing power (FRAP). The 50% ethanol extract showed strong antioxidative activity against DPPH and FRAP, with IC50 ± SEM [μg/mL] values of 9.38 ± 0.46 and 15.46 ± 0.52, respectively. The antioxidative activity-guided fractionations were performed according to the DPPH and FRAP screening results. Fourteen fractions from the 50% ethanol extract showed dissimilar antioxidative activity against DPPH and FRAP of 8.16 ± 0.76 ∼ 38.42 ± 0.58 μg/mL and 13.22 ± 0.68 ∼ 61.47 ± 0.49 μg/mL. The chemical assay-guided separation of the active fractions (fractions 3, 6, 7 and 8) led to eight phenols: protocatechuic aldehyde (<b>1</b>), ethyl gallate (<b>2</b>), rhododendrin (<b>3</b>), <b>p</b>-hydroxyacetophenone (<b>4</b>), rhododendrol (<b>5</b>), protocatechuic acid ethyl ester (<b>6</b>), frambinone (<b>7</b>) and ethylparaben (<b>8</b>). All phenols are reported here for the first time from <b>S. tangutica</b> Engl. Protocatechuic aldehyde (<b>1</b>), ethyl gallate (<b>2</b>), rhododendrin (<b>3</b>) and protocatechuic acid ethyl ester (<b>6</b>) showed strong antioxidative activities (IC50 ± SEM [mM] between 8.79 ± 0.15 and 4.25 ± 0.47 and between 6.15 ± 0.48 and 2.83 ± 0.49) against DPPH and FRAP.

This study presents an efficient strategy based on liquid-liquid extraction, high-speed counter-current chromatography, and preparative HPLC for the rapid enrichment, separation, and purification of four anthraquinones from Rheum tanguticum. A new solvent system composed of petroleum ether/ethyl acetate/water (4:2:1, v/v/v) was developed for the liquid-liquid extraction of the crude extract from R. tanguticum. As a result, emodin, aloe-emodin, physcion, and chrysophanol were greatly enriched in the organic layer. In addition, an efficient method was successfully established to separate and purify the above anthraquinones by high-speed counter-current chromatography and preparative HPLC. This study supplies a new alternative method for the rapid enrichment, separation, and purification of emodin, aloe-emodin, physcione, and chrysophanol.

In this paper, an efficient method was successfully established by the combination of macroporous resin (MR) and high-speed counter-current chromatography (HSCCC) for rapid enrichment and separation of aloe-emodin 8-O-β-D-glucoside, emodin 1-O-β-D-glucoside, emodin 8-O-β-D-glucoside and piceatannol 4'-O-β-D-(6″-O-gallate)-glucoside. Six kinds of macroporous resins were investigated in the first step and X-5 macroporous resin was selected for the enrichment of the target compounds. The recoveries of the target compounds reached 89.0, 85.9, 82.3 and 84.9% respectively after 40% ethanol elution. In the second step, the target compounds were separated by HSCCC with a two-phase solvent system composed of chloroform/ethyl acetate/methanol/water (8:1:6:5, v/v). The established method will be helpful for further characterization and utilization of Rheum tanguticum. The results demonstrate that MR coupled with HSCCC is a powerful technique for separation of bioactive compounds from natural products.

A comparative analysis was undertaken to conduct an anatomical and micromorphological study of five species of Rhodiola—<i>R. kirilowii, R. yunnanensis, R. crenulata, R. fastigata</i>, and <i>R. quadrifida</i>—collected from the western Sichuan province plateau of China. Rhodiola plants are a popularly used ethnodrug from the Qinghai-Tibetan plateau of China. Modern studies have shown that the plants of Rhodiola possess different pharmacological activities, chemical constituents, and efficiencies in clinical application. To distinguish five main species of Rhodiola and ensure their safety and efficacy, microscopic characteristics of roots, rhizomes, and stems, including transverse sections, stem and foliar epidermis, as well as the crude drug powder, were observed. The fixed, sectioned, and stained plant materials, as well as the crude powder, were studied using a light microscope according to the usual microscopic techniques. The results of the microscopic features were systematically and comparatively described and illustrated. The five species have distinct microscopic characteristic differences, thus allowing us to distinguish between the species. Also, semi-quantitative and quantitative micrographic parameter tables were simultaneously presented. Further, a key to the five species and a comparative chart of the key authentication parameters based on these anatomic characteristics analyzed was drawn up and is presented for the Rhodiola species studied. The study indicated that light microscopy and related techniques provide a method that is convenient, feasible, and can be unambiguously applied to the authentication of species of Rhodiola. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc.

As important secondary plant metabolites, naphthoquinones exhibit a wide range of biological activities. However, their potential as sustainable alternatives to synthetic acaricides has not been studied. This study for the first time investigates the acaricidal activity of naphthoquinones against Psoroptes cuniculi in vitro. Furthermore, the in vivo activity, the skin irritation effects, the cytotoxicity and the inhibitory activities against mite acetylcholinesterase (AChE) and glutathione S-transferase (GST) of the two compounds that displayed the best insecticidal activity in vitro were evaluated. Among fourteen naphthoquinones and their analogs, juglone and plumbagin were observed to possess the strongest acaricidal activities against P. cuniculi with LC50 values of 20.53 ppm and 17.96 ppm, respectively, at 24 h. After three treatments, these two chemicals completely cured naturally infested rabbits in vivo within 15 days, and no skin irritation was found in any of the treated rabbits. Compared to plumbagin, juglone presented no or weak cytotoxicity against HL-7702 cells. Moreover, these two chemicals significantly inhibited AChE and GST activity. These results indicate that juglone has promising toxicity against P. cuniculi, is safe for both humans and animals at certain doses, and could be used as a potential alternative bio-acaricide for controlling the development of psoroptic mange in agricultural applications.

Abstract: In the present paper, the effect of the aqueous extract from aerial parts of Artemisia vestita (AV-ext), a traditional Tibetan medicine, on ear contact sensitivity was examined. AV-ext significantly reduced the ear swelling when administered during the induction phase of picryl-chloride (PCl)-induced ear contact sensitivity in mice. The extract also showed a dose-dependent inhibition on lymphocyte proliferation and IL-2 production in Con A-activated spleen cells. The proliferation inhibition was confirmed in the mixed lymphocytes reaction. Furthermore, the adhesion of the isolated spleen cells from PCl-sensitized mice to type IV collagen was significantly decreased in a dose-dependent manner by AV-ext. Such decrease was also seen in AV-ext-treated Jurkat T cells and the T cells purified from above spleen cells. The purified spleen T cells from PCl-sensitized mice produced more matrix metalloproteinase-9 (MMP-9) than naive T cells, and AV-ext remarkably reduced MMP-9 production both in vivo and in vitro. These results suggest that AV-ext may alleviate contact sensitivity through blocking the activation of T lymphocytes and decreasing their localization to the inflammatory sites via down-regulating the potential of cell adhesion and metalloproteinase production.

Because of the morphological and macroscopic similarity, many species of Erigeron and Aster (Asteraceae) are confusable and usually used under the same name "Meiduoluomi" in traditional Tibetan medicine (TTM). To find an easy, quick, and reliable method to authenticate and distinguish the eight main medicinal plants of these species, the light microscope was used to reveal the morphoanatomic details. The fixed, sectioned, and stained plant materials and epidermis materials were studied by microscopic techniques. The results of the microscopic features are systematically described and illustrated, and comparison parameters are presented. Furthermore, a key to the eight species of "Meiduoluomi" was constructed. Microscopy can be unambiguously used to authenticate and distinguish the eight main species of TTM "Meiduoluomi.";

Because of the morphological and macroscopic similarity, many species of <i>Erigeron</i> and <i>Aster</i> (Asteraceae) are confusable and usually used under the same name “Meiduoluomi” in traditional Tibetan medicine (TTM). To find an easy, quick, and reliable method to authenticate and distinguish the eight main medicinal plants of these species, the light microscope was used to reveal the morphoanatomic details. The fixed, sectioned, and stained plant materials and epidermis materials were studied by microscopic techniques. The results of the microscopic features are systematically described and illustrated, and comparison parameters are presented. Furthermore, a key to the eight species of “Meiduoluomi” was constructed. Microscopy can be unambiguously used to authenticate and distinguish the eight main species of TTM “Meiduoluomi.” Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc.

Rhodiola is an increasingly widely used traditional Tibetan medicine and traditional Chinese medicine in China. The composition profiles of bioactive compounds are somewhat jagged according to different species, which makes it crucial to identify authentic Rhodiola species accurately so as to ensure clinical application of Rhodiola . In this paper, a nondestructive, rapid, and efficient method in classification of Rhodiola was developed by Fourier transform near-infrared (FT-NIR) spectroscopy combined with chemometrics analysis. A total of 160 batches of raw spectra were obtained from four different species of Rhodiola by FT-NIR, such as Rhodiola crenulata , Rhodiola fastigiata , Rhodiola kirilowii , and Rhodiola brevipetiolata . After excluding the outliers, different performances of 3 sample dividing methods, 12 spectral preprocessing methods, 2 wavelength selection methods, and 2 modeling evaluation methods were compared. The results indicated that this combination was superior than others in the authenticity identification analysis, which was FT-NIR combined with sample set partitioning based on joint x-y distances (SPXY), standard normal variate transformation (SNV) + Norris-Williams (NW) + 2nd derivative, competitive adaptive reweighted sampling (CARS), and kernel extreme learning machine (KELM). The accuracy (ACCU), sensitivity (SENS), and specificity (SPEC) of the optimal model were all 1, which showed that this combination of FT-NIR and chemometrics methods had the optimal authenticity identification performance. The classification performance of the partial least squares discriminant analysis (PLS-DA) model was slightly lower than KELM model, and PLS-DA model results were ACCU = 0.97, SENS = 0.93, and SPEC = 0.98, respectively. It can be concluded that FT-NIR combined with chemometrics analysis has great potential in authenticity identification and classification of Rhodiola , which can provide a valuable reference for the safety and effectiveness of clinical application of Rhodiola . [ABSTRACT FROM AUTHOR]

Rhodiola is an increasingly widely used traditional Tibetan medicine and traditional Chinese medicine in China. The composition profiles of bioactive compounds are somewhat jagged according to different species, which makes it crucial to identify authentic Rhodiola species accurately so as to ensure clinical application of Rhodiola. In this paper, a nondestructive, rapid, and efficient method in classification of Rhodiola was developed by Fourier transform near-infrared (FT-NIR) spectroscopy combined with chemometrics analysis. A total of 160 batches of raw spectra were obtained from four different species of Rhodiola by FT-NIR, such as Rhodiola crenulata, Rhodiola fastigiata, Rhodiola kirilowii, and Rhodiola brevipetiolata. After excluding the outliers, different performances of 3 sample dividing methods, 12 spectral preprocessing methods, 2 wavelength selection methods, and 2 modeling evaluation methods were compared. The results indicated that this combination was superior than others in the authenticity identification analysis, which was FT-NIR combined with sample set partitioning based on joint x-y distances (SPXY), standard normal variate transformation (SNV) + Norris-Williams (NW) + 2nd derivative, competitive adaptive reweighted sampling (CARS), and kernel extreme learning machine (KELM). The accuracy (ACCU), sensitivity (SENS), and specificity (SPEC) of the optimal model were all 1, which showed that this combination of FT-NIR and chemometrics methods had the optimal authenticity identification performance. The classification performance of the partial least squares discriminant analysis (PLS-DA) model was slightly lower than KELM model, and PLS-DA model results were ACCU = 0.97, SENS = 0.93, and SPEC = 0.98, respectively. It can be concluded that FT-NIR combined with chemometrics analysis has great potential in authenticity identification and classification of Rhodiola, which can provide a valuable reference for the safety and effectiveness of clinical application of Rhodiola.

Abstract Juniperus pingii var. wilsonii has been traditionally used in Tibetan medicine for the treatment of inflammatory diseases. In the present study, J. pingii var. wilsonii polysaccharides (JPWP), with high content of d ‑galacturonic acid, showed potent anti-complementary activity in vitro and significantly attenuated acute lung injury (ALI) induced by H1N1 influenza virus in vivo through reducing the inflammatory responses, alleviating oxidative stress and inhibiting the activation of complement. Thus, anti-complementary activity-guided fractionation of JPWP led to the isolation of an acidic homogeneous polysaccharide, JPWP-PS, whose structure was further elucidated by acid hydrolysis, PMP derivation, methylation and NMR analysis. JPWP-PS had potent anti-complementary activity with the CH 50 value of 0.073 ± 0.009 mg/mL, and was characterized by the residues of T-Ara f -(1→, →3)-Ara f -(1→, →3,5)-Ara f -(1→, →3)-Gal p -(1→ and →4)-Gal p A-(1→. Graphical abstract Unlabelled Image Highlights • Juniperus pingii var. wilsonii polysaccharides (JPWP) improved survival rate of H1N1 virus infected mice. • JPWP treated acute lung injury via inhibiting inflammatory responses, oxidative stress and activation of complement. • A homogeneous acidic polysaccharide with potent anti-complementary activity was isolated from JPWP. [ABSTRACT FROM AUTHOR]

Background: Veronica ciliata Fisch., widely distributed in western China, has been traditionally used in Tibetan Medicine as a treatment for hepatitis, cholecystitis, rheumatism, and urticaria. However, V. ciliata Fisch. has not been subjected to detailed chemical constitution analysis and the bioactive studies were restricted to its crude extracts. It is necessary to investigate the active chemical components of these extracts and identify their biological effects. Results: Four iridoid glycosides, (veronicoside, cataposide, amphicoside, and verminoside) were isolated from the ethyl acetate fraction. Among these compounds, veronicoside and verminoside were isolated for the first time from this plant. These compounds exhibited strong antioxidant activity and inhibitory activity on HepG2 cell proliferation. The antioxidant activity of verminoside was equal to Vc. Cataposide, amphicoside and verminoside had stronger anti-hepatocarcinoma activity than 5-fluorouracil. Conclusions: Four iridoid glycosides,(veronicoside, cataposide, amphicoside and verminoside) were isolated from the extract of V. ciliata Fisch. using bioassay-guided screening.Among these compounds, veronicoside and verminoside were isolated for the first time from this plant. The above results indicated that these compounds were the active chemical components responsible for the antioxidant and anti-hepatocarcinoma properties of V. ciliata Fisch. The underlying mechanism of their bioactivity is worthy of further investigation. [Figure not available: see fulltext. Caption: Bioactivity-guided isolation of antioxidant and anti-hepatocarcinoma constituents from Veronica ciliata]

Biocompatible and bioresponsive microneedles (MNs) are emerging technology platforms for sustained drug release with a potential to be a key player in transdermal delivery of therapeutics. In this paper, an innovative biodegradable MNs patch for the sustained delivery of drugs using a polymer patch, which can adjust delivery rates based on its crosslinking degree, is reported. Gelatin methacryloyl (GelMA) is used as the base for engineering biodegradable MNs. The anticancer drug doxorubicin (DOX) is loaded into GelMA MNs using the one molding step. The GelMA MNs can efficiently penetrate the <i>stratum corneum</i> layer of a mouse cadaver skin. Mechanical properties and drug release behavior of the GelMA MNs can be adjusted by tuning the degree of crosslinking. The efficacy of the DOX released from the GelMA MNs is tested and the anticancer efficacy of the released drugs against melanoma cell line A375 is demonstrated. Since GelMA is a versatile material in engineering tissue scaffolds, it is expected that the GelMA MNs can be used as a platform for the delivery of various therapeutics.<br><b>A biocompatible and biodegradable microneedles patch</b> based on gelatin methacryloyl are developed for transcutaneous delivery of drugs. The microneedles can efficiently penetrate the <i>stratum corneum</i> layer in a mouse cadaver skin model and the drug release profile can be controlled by tuning the crosslinking degrees. The model drug doxorubicin keeps its anticancer efficacy after enzyme-mediated release from the patch.

To follow-up on our prior Part I review, this Part II review summarizes and provides updated literature on novel quinoline and quinazoline alkaloids isolated during the period of 2009-2016, together with the biological activity and the mechanisms of action of these classes of natural products. Over 200 molecules with a broad range of biological activities, including antitumor, antiparasitic and insecticidal, antibacterial and antifungal, cardioprotective, antiviral, anti-inflammatory, hepatoprotective, antioxidant, anti-asthma, antitussive, and other activities, are discussed. This survey should provide new clues or possibilities for the discovery of new and better drugs from the original naturally occurring quinoline and quinazoline alkaloids.

<p>An excerpt of the verb entries from ZHANG (<em>Bod rgya tshig mdzod chen mo / Zhang Han Da Cidian</em> [Great Tibetan Chinese Dictionary]. Beijing: Mi rigs dpe skrun kang / Minzu Chubanshe, 1985)</p>

To induce callus and establish rapid propagation systems for Veronica ciliate Fisch., terminal buds from its aseptic seedlings were cultured in MS mediums with different concentration combinations of NAA and 6-BA. Results showed that the optimum medium for callus inducement was MS + 6-BA 0. 5 mg/L + NAA 1. 0 mg/L, with the callus induction rate of 95%. The best medium for multiplication was MS + 6-BA 0. 5 mg/L + NAA 0. 1 mg/L,with the multiplication coefficient reaching 5. 4. The optimum root medium for multiple shoot clumps was 1/2 MS + IBA 0. 05 mg/L,with the rooting rate reaching 95% and the root being healthiest. Under suitable hardening and transplanting conditions, the highest survival rate for the regenerated plantlets reached 40%.

Five days of integrative body-mind training (IBMT) improves attention and self-regulation in comparison with the same amount of relaxation training. This paper explores the underlying mechanisms of this finding. We measured the physiological and brain changes at rest before, during, and after 5 days of IBMT and relaxation training. During and after training, the IBMT group showed significantly better physiological reactions in heart rate, respiratory amplitude and rate, and skin conductance response (SCR) than the relaxation control. Differences in heart rate variability (HRV) and EEG power suggested greater involvement of the autonomic nervous system (ANS) in the IBMT group during and after training. Imaging data demonstrated stronger subgenual and adjacent ventral anterior cingulate cortex (ACC) activity in the IBMT group. Frontal midline ACC theta was correlated with highfrequency HRV, suggesting control by the ACC over parasympathetic activity. These results indicate that after 5 days of training, the IBMT group shows better regulation of the ANS by a ventral midfrontal brain system than does the relaxation group. This changed state probably reflects training in the coordination of body and mind given in the IBMT but not in the control group. These results could be useful in the design of further specific interventions.

Children spend a lot of time watching television on its many platforms: directly, online, and via videos and DVDs. Many researchers are concerned that some types of television content appear to negatively influence children's executive function. Because (1) executive function predicts key developmental outcomes, (2) executive function appears to be influenced by some television content, and (3) American children watch large quantities of television (including the content of concern), the issues discussed here comprise a crucial public health issue. Further research is needed to reveal exactly what television content is implicated, what underlies television's effect on executive function, how long the effect lasts, and who is affected.

OBJECTIVE: To investigate the chemical components and microstructure of Nengchi Bajin ashes which are adjuvant material in the refining of Tibetan medicine gTSo thal, in order to explore the material basis of the refining of gTSo thal.METHOD: Scanning electron microscope-energy dispersive spectrometer (SEM-EDX) and X-ray diffraction (XRD) were used to measure the Nengchi Bajin ashes. RESULT: SEM-EDX analysis show that except of themselves elements of Nengchi Bajin ashes, Nengchi Bajin ashes contain the major elements, such as S, O, C and so on, also contain small amount other elements. XRD analysis show that the structures are AuPb2, PbO (tetragonal and orthorhombic) and Pb in gold ash, Ag2S and PbO in silver ash, Cu1.98 (Zn0.73 Fe0.29)Sn0.99 S4, CuS, SiO2, NaCu2S2 and Ca (Fe(+2), Mg) (CO3)2 in bronze ash, Cu7S4 (orthorhombic and monoclinic) and CuO in red copper ash, Cu7 S4, PbS, ZnS, CaCO3and NaCu2S2 in brass ash, FeS, Fe+2 Fe(2+3)O4 and SiO2 in iron ash, SnS and SiO2 tin ash, PbS, PbSO4 and SnS2 in lead ash. CONCLUSION: We have acquired the datum of elements and microstructure of Nengchi Bajin ashes by SEM-EDX and XRD techniques, and that is benefit to explore the material basis of refining gTSo thal.

Zhuxi is a mineral medicine widely used in traditional Tibetan medicine throughout history. However, the bioactive component in Zhuxi still remains unclear. In order to enunciate the material basis of its pharmacological activity, the present research has determined the chemical component and structure of Zhuxi. X-ray fluorescence spectroscopy (XRF), inductively coupled plasma optical emission spectrometer (ICP-OES) and X-ray diffraction (XRD) were utilized to assay two samples of Zhuxi. XRF and ICP-OES analysis indicated that the main elements in Zhuxi are Fe, S and O, also containing some minor elements, such as Si, Na, Mg, Al, K, Ni, Ca, Ti and so on. XRD analysis suggested that the main crystal compound in Zhuxi is FeS2 (Cubic, Pa-3), also existing a few of Fe(+3)O(OH) (orthorhombic, Pbnm) and other some unknown compounds. These studies has highlighted the potential the element components and compound structures of Zhuxi, so it may be a good starting point for exploring the material basis of its pharmacological activity.

In order to reveal the chemical substance basis of pharmacodynamic effects of Zuotai, energy dispersive spectrometry of X-ray (EDX), X-ray fluorescence spectroscopy (XRF), synchrotron radiation X-ray absorption fine structure (SR-XAFS), X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM) were used to analyze the elements, the chemical valence and local structure of mercury, and the chemical phase composition and micro-morphology of Zuotai. EDX and XRF analysis shows that the main elements in Zuotai are Hg and S, with some other minor elements, such as 0, Fe, Al, Cu, K, Ag, Ca, Mg etc. SR-XAFS analysis shows that: the oxidation state of mercury in Zuotai is divalence, its neighbor atoms are S, and its coordination number is four. XRD assay found that β-HgS (cubic, F-43m 216) and S8 (orthorhombic, Fddd 70) are the main phase compositions in Zuotai. Besides, it also has a small amount of C (hexagonal, P63/mmc 194), Fel.05 S0.95 (hexagonal, P63/mmc 194), Cu6S6 (hexagonal, P63/mmc 194), Cu1.8 S (cubic, F-43m 216) and so on. And it was found that the crystallinity of Zuotai is about 59%, and the amorphous morphology substance in it is about 41%. SEM and AFM detection suggests that Zuotai is a kind of ancient micro-nano drug, and its particle size is mainly in the range of 100-600 nm, even less than 100 nm, which commonly further aggregate into several to 30 µm loose amorphous particles. In summary, the present study elucidated physicochemical characterization(elements composition, coordination information of mercury, phase composition and micro-morphology) of Zuotai, and it will play a positive role in promoting the interpretation of this mysterious drug.;

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