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A new triterpenoid, namely myricarin C (compound 1), together with three known compounds myricarin A (compound 2) and myricarin B (compound 3), 3α-hydroxy-D-friedoolean-14-en-28-oic acid (compound 4), was isolated from the overground part of Myricaria squamosa. Compound 2 and compound 3 existed in the solution by the form of cis-trans isomers. Their structures were elucidated by means of extensive spectroscopic methods, including 1D-NMR, 2D-NMR, and HR-ESI-MS. The antioxidant properties of all compounds were calculated based on the DPPH radical scavenging activities. Results showed that myricarin A and myricarin C had general antioxidant activities with EC50 values of 40.90 μg/ml, 42.22 μg/ml, respectively, compared to the control, rutin (5.17 μg/ml). The EC50 values of myricarin B was 195.81 μg/ml. Compound 4 had no antioxidant activities.

A new triterpenoid, namely myricarin C (compound 1), together with three known compounds myricarin A (compound 2) and myricarin B (compound 3), 3α-hydroxy-D-friedoolean-14-en-28-oic acid (compound 4), was isolated from the overground part of Myricaria squamosa. Compound 2 and compound 3 existed in the solution by the form of cis-trans isomers. Their structures were elucidated by means of extensive spectroscopic methods, including 1D-NMR, 2D-NMR, and HR-ESI-MS. The antioxidant properties of all compounds were calculated based on the DPPH radical scavenging activities. Results showed that myricarin A and myricarin C had general antioxidant activities with EC50 values of 40.90 μg/ml, 42.22 μg/ml, respectively, compared to the control, rutin (5.17 μg/ml). The EC50 values of myricarin B was 195.81 μg/ml. Compound 4 had no antioxidant activities.

Traditional Tibetan medicine is important for discovery of drug precursors. However, information about the chemical composition of traditional Tibetan medicine is very limited due to the lack of appropriate chromatographic purification methods. In the present work, A. kansuensis was taken as an example and a novel two-dimensional reversed-phase/hydrophilic interaction liquid chromatography(HILIC) method based on on-line HPLC-DPPH bioactivity-guided assay was developed for the purification of analogue antioxidant compounds with high purity from the extract of A. kansuensis. Based on the separation results of many different chromatographic stationary phases, the first-dimensional (1D) preparation was carried on a RP-C18HCE prep column, and 2 antioxidant fractions were obtained from the 800mg crude sample with a recovery of 56.7%. A HILIC-XAmide prep column was selected for the second-dimensional (2D) preparation. Finally, a novel antioxidant β-carboline Alkaloids (Glusodichotomine AK) and 4 known compounds (Tricin, Homoeriodictyol, Luteolin, Glucodichotomine B) were purified from A. kansuensis. The purity of the compounds isolated from the crude extract was >98%, which indicated that the method built in this work was efficient to manufacture single analogue antioxidant compounds of high purity from the extract of A. kansuensis. Additionally, this method showed great potential in the preparation of analogue structure antioxidant compounds and can serve as a good example for the purification of analogue structure antioxidant carboline alkaloids and flavonoids from other plant materials.

Zuotais regarded as the king of Tibetan medicine. However, the major starting material ofZuotais mercury, which is one very toxic heavy metal. This has aroused serious doubts on the biosafety ofZuotacontaining drugs. In this study, we quantified the Hg contents in fourZuotasamples, monitored the release of Hg in simulated gastric/intestinal juice and evaluated their cytotoxicity to Caco-2 cells. Our results showed that the Hg contents inZuotasamples were in the range of 566–676 mg/g. Fortunately, the release of Hg fromZuotasamples was very low in simulated gastric juice, and much lower in simulated intestinal juice. Direct contact ofZuotawith Caco-2 cells led to dose-dependent cytotoxicity, including activity loss and membrane leakage. The toxicity was closely related to apoptosis, because the caspase 3/7 levels of Caco-2 cells increased after the exposure toZuota. Interestingly,Zuotasamples inhibited the oxidative stress at low concentrations, but the toxicity could be relived by antioxidants. The possible toxicity should be attributed to the cellular uptake ofZuotaparticulates. Beyond the cytotoxicity, significant differences amongZuotasamples from different institutions were observed, suggesting that the preparation process ofZuotahad meaningful influence of its biosafety. The implications to the safety and clinical applications ofZuotaare discussed. [ABSTRACT FROM AUTHOR]

OBJECTIVES: We conducted a quality improvement project to determine (1) what information providers and patients most wanted to learn about complementary and integrative health (CIH) therapies and (2) in what format they wanted to receive this information. The overall aim was to develop educational materials to facilitate the CIH therapy decision-making processes. DESIGN: We used mixed methods to iteratively pilot test and revise provider and patient educational materials on yoga and meditation. We conducted semistructured interviews with 11 medical providers and held seven focus groups and used feedback forms with 52 outpatients. We iteratively developed and tested three versions of both provider and patient materials. Activities were conducted at four Veterans Administration medical facilities (two large medical centers and two outpatient clinics). RESULTS: Patients want educational materials with clearly stated basic information about: (1) what mindfulness and yoga are, (2) what a yoga/meditation class entails and how classes can be modified to suit different abilities, (3) key benefits to health and wellness, and (4) how to find classes at the hospital/clinic. Diverse media (videos, handouts, pocket guides) appealed to different Veterans. Videos should depict patients speaking to patients and demonstrating the CIH therapy. Written materials should be one to three pages with colors, and images and messages targeting a variety of patients. Providers wanted a concise (one-page) sheet in black and white font with no images listing the scientific evidence for CIH therapies from high-impact journals, organized by either type of CIH or health condition to use during patient encounters, and including practical information about how to refer patients. CONCLUSIONS: Providers and patients want to learn more about CIH therapies, but want the information in succinct, targeted formats. The information learned and materials developed in this study can be used by others to educate patients and providers on CIH therapies.

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