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A new proaporphine alkaloid, 8, 9-dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of Meconopsishorridula Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods.

A new proaporphine alkaloid, 8, 9<b>-</b>dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of <b>Meconopsis</b> <b>horridula</b> Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods.<br>8, 9-Dihydroprooxocryptochine, a new proaporphine alkaloid from <b>Meconopsis</b> <b>horridula</b>, a tradional Tibetan medicine.<br>▪

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.

A selective and affinitive molecularly imprinting polymer (MIP) was prepared to podophyllotoxin (PPT) using a non-covalent imprinting approach. The imprinted conditions including the kind and relative amounts of functional and cross-linking monomers were carefully optimized. The binding characteristics of the imprinted polymer were evaluated in different solvent systems using equilibrium binding experiments. UV spectrum revealed cooperative hydrogen-bonding complex between PPT and acylamide (AM) might be formed at the ratio of 1:2 in the prepolymerized system, and produced two classes of binding sites in the resulting MIP with dissociation constants of 0.337 and 5.76 mmol l−1, and the affinity binding sites of 78.67 and 346.0 μmol g−1, respectively. Selective binding of the template molecule is demonstrated in comparison to the analogue 4′-demethylpipodophyllotoxin (DMEP). Finally, the optimized MIP was used as an adsorbent to extract PPT directly from the ethanol extraction of Chinese traditional Tibetan medicine, <b>Sinopodophyllum emodi</b>. The binding selectivity and recovery of the optimized imprinted polymer had been further estimated by HPCE and compared to its non-imprinted polymer. The obtained results implied a possibility to extract PPT directly from plants by a MIP technique shown in this paper.

<b>OBJECTIVES: </b> To better understand the occurrence of Crohn's disease in mainland China and to give an updated overview of the current status of the disease.<br><b>METHODS: </b> We previously performed a computer-based literature search using 50 years of records from the Chinese Database of Biology and Medicine (1979 to 2002), combined with a manual year-by-year search of the literature from 1950 to 1978. Using a similar method, descriptive epidemiological data of the last 5 years (2003 to September 2007) were collected, pooled with our previous data and re-analyzed.<br><b>RESULTS: </b> In total, 3618 cases of Crohn's disease since 1950 have been reported from 29 provinces and cities in mainland China, comprising 2112 male and 1506 female patients, with a male predominance of 1.40:1. More than 75 percent of the patients were aged from 20 to 50 years old, with a mean age of 36.9 ± 4.4 (1- 84) years. The extrapolated disease incidence and prevalence rates are 0.848/10⁵ and 2.29/10⁵ person/year, respectively.<br><b>CONCLUSION: </b> The incidence and prevalence rates of Crohn's disease have been increasing rapidly, and the disease is no longer uncommon in China, but these rates are still lower than those in developed countries and other Asian countries. An underestimation may occur because patients who were misdiagnosed or did not seek medical advice could not be included in the study. A future population-based survey is warranted.

Chrysosplenium nudicaule,Tibetan name " Yajima",is recorded as an effective medicine for the treatment of liver and gallbladder diseases by Tibetan Pharmacopoeia published in the past dynasties,but its traditional efficacy has not yet been investigated by means of modern pharmacological research methods. In this paper,the protective effect of extract of C. nudicaule(ECN) on liver injury in mice was observed by using the mice model of intrahepatic cholestasis(IC) induced by α-naphthyl isothiocyanate(ANIT) and the possible mechanism by which ECN work as the therapeutic agent was discussed. The results showed that the serum levels of AST,ALT,ALP,DBIL,TBIL and TBA of the model mice were notably reduced in dose-dependent manner(P<0. 01,P<0. 05). The activity of SOD and GSH-Px in the liver homogenate of mice was increased,while the content of MDA was decreased(P<0. 01,P<0. 05).Pathological examination of liver in mice showed that ECN could improve the pathological changes of liver tissue in mice. The mRNA expression level of genes related to bile acid metabolism were detected by RT-PCR and the results suggested that ECN could significantly increase the expression of genes such as BSEP,FXR and MRP2(P<0. 01,P<0. 05),meanwhile significantly reduce the expression of CYP7 A1(P<0. 01,P<0. 05). These results confirmed the protective effect of ECN on intrahepatic cholestasis-induced liver injury in mice,and indicated that the mechanism may be related to activating FXR and its target genes,reducing bile acid synthesis and increasing bile acid excretion. This study provides a modern pharmacological basis for the clinical application of Yajima in Tibetan medicine.

The present study examined the reliability and validity of a Chinese translation of the Mindful Attention Awareness Scale (MAAS). Three questionnaires, the MAAS, the Positive and Negative Affect Schedule (PANAS), and the brief version of the World Health Organization's Quality of Life (WHOQOL-BREF), were completed by 263 Chinese undergraduates (207 males, 56 females). Seventy of these students were assessed again with the MAAS after 20 days to evaluate the scale's test–retest reliability. Results from confirmatory factory analysis indicated that a one-factor solution fit the MAAS data satisfactorily. Reliability coefficients, including Cronbach's alpha, Guttman split-half, item–total correlations, and test–retest, were also satisfactory. Addressing validity, the MAAS was negatively correlated with PANAS negative affect and positively associated with PANAS positive affect as well as with the quality of life indexed by the WHOQOL-BREF. The Chinese version of the MAAS appears to be a reliable and valid instrument to assess levels of mindfulness in a Chinese college population.

Amyloid-beta peptide is central to the pathology of Alzheimer's disease, because it is neurotoxic—directly by inducing oxidant stress, and indirectly by activating microglia. A specific cell-surface acceptor site that could focus its effects on target cells has been postulated but not identified. Here we present evidence that the 'receptor for advanced glycation end products' (RAGE) is such a receptor, and that it mediates effects of the peptide on neurons and microglia. Increased expression of RAGE in Alzheimer's disease brain indicates that it is relevant to the pathogenesis of neuronal dysfunction and death.

Objective: Between 2% and 8% of college students meet criteria for ADHD, with increased incidence in recent decades. There are very few clinical trials conducted on the meaningful intervention of ADHD in college. Mindfulness-based cognitive therapy (MBCT) effectively treats college students with ADHD and could be more feasibly applied in college mental health clinics. Method: Fifty-four undergraduates with ADHD between ages 19 and 24 were randomized to receive either MBCT or wait-list (WL) during a 6-week intervention phase. ADHD symptoms, neuropsychological performance, and related outcomes were assessed at pre-treatment, post-treatment, and 3-month follow-up. Results: Participants receiving MBCT group showed greater treatment response rates (57%-71% vs. 23%-31%) and experience less anxiety and depression, and greater levels of mindfulness; MBCT participants show greater improvement on neuropsychological performance. Conclusion: MBCT may be a useful intervention for college students with ADHD, improving participants’ ADHD symptoms, mindfulness, and sustained attention.

<i>Saussurea laniceps</i> (Compositae), commonly known as “cotton-headed snow lotus”, is the most effective “snow lotus” used in both Tibetan and Chinese folk medicine. It performs outstandingly in treating rheumatoid arthritis, which mainly is credited for its anti-inflammatory and anti-nociceptive efficacy, as explained by modern pharmacological studies. Extracts of the herb, including umbelliferone and scopoletin, exert such effects in various in vivo and in vitro studies. Besides the two chemicals above, more than 100 organic compounds have been found in <i>S. laniceps</i>, and 58 of them are presented here in molecular structure, including cynaropicrin, mokko lactone, apigenin, acacetin, and luteolin, all contributing to different bioactivities, such as analgesic, antioxidant, immunomodulatory, anti-microbial and anticancer effects. We provide a natural product library of <i>S. laniceps</i>, giving inspirations for structure modification and bioactivity-oriented screening, enabling sustainable use of this valuable plant. The ethnomedical applications and pharmacological discoveries are compared and crosslinked, revealing modern evidence for traditional usages. Despite that <i>S. laniceps</i> is a representative “snow lotus” herb, its material medica records and clinical applications are complicated; there is considerable confusion with the different snow lotuses in the academic community and on the market. This review also aims at clearing such confusion, and improving quality assessment and control of the herb. To better utilize the valuable plant, further comparison among the chemical constitutions, pharmacological activities and therapeutic mechanisms of different snow lotuses are needed.

Chronic inflammation is associated with various chronic illnesses including immunity disorders, cancer, neurodegeneration, and vascular diseases. Iridoids are compounds with anti-inflammatory properties. However their anti-inflammatory mechanism remains unclear. Here, we report that scropolioside B, isolated from a Tibetan medicine (Scrophularia dentata Royle ex Benth.), blocked expressions of TNF, IL-1, and IL-32 through NF-κB pathway. Scropolioside B inhibited NF-κB activity in a dose-dependent manner with IC50 values of 1.02 μmol/L. However, catalpol, similar to scropolioside B, was not effective in inhibiting NF-κB activity. Interestingly, scropolioside B and catalpol decreased the expression of NLRP3 and cardiolipin synthetase at both the mRNA and protein level. Our results showed that scropolioside B is superior in inhibiting the expression, maturation, and secretion of IL-1β compared to catalpol. These observations provide further understanding of the anti-inflammatory effects of iridoids and highlight scropolioside B as a potential drug for the treatment of rheumatoid arthritis and atherosclerosis.

Chronic inflammation is associated with various chronic illnesses including immunity disorders, cancer, neurodegeneration, and vascular diseases. Iridoids are compounds with anti-inflammatory properties. However their anti-inflammatory mechanism remains unclear. Here, we report that scropolioside B, isolated from a Tibetan medicine (Scrophularia dentata Royle ex Benth.), blocked expressions of TNF, IL-1, and IL-32 through NF-κB pathway. Scropolioside B inhibited NF-κB activity in a dose-dependent manner with IC50 values of 1.02 μmol/L. However, catalpol, similar to scropolioside B, was not effective in inhibiting NF-κB activity. Interestingly, scropolioside B and catalpol decreased the expression of NLRP3 and cardiolipin synthetase at both the mRNA and protein level. Our results showed that scropolioside B is superior in inhibiting the expression, maturation, and secretion of IL-1β compared to catalpol. These observations provide further understanding of the anti-inflammatory effects of iridoids and highlight scropolioside B as a potential drug for the treatment of rheumatoid arthritis and atherosclerosis.

Chronic inflammation is associated with various chronic illnesses including immunity disorders, cancer, neurodegeneration, and vascular diseases. Iridoids are compounds with anti-inflammatory properties. However their anti-inflammatory mechanism remains unclear. Here, we report that scropolioside B, isolated from a Tibetan medicine (Scrophularia dentata Royle ex Benth.), blocked expressions of TNF, IL-1, and IL-32 through NF-κB pathway. Scropolioside B inhibited NF-κB activity in a dose-dependent manner with IC50 values of 1.02 μmol/L. However, catalpol, similar to scropolioside B, was not effective in inhibiting NF-κB activity. Interestingly, scropolioside B and catalpol decreased the expression of NLRP3 and cardiolipin synthetase at both the mRNA and protein level. Our results showed that scropolioside B is superior in inhibiting the expression, maturation, and secretion of IL-1β compared to catalpol. These observations provide further understanding of the anti-inflammatory effects of iridoids and highlight scropolioside B as a potential drug for the treatment of rheumatoid arthritis and atherosclerosis.

A feasibility research was performed to study the possibilities of using a molecularly imprinted polymer as sorbent material in solid-phase extraction for the separation of active inhibitors of epidermal growth factor receptor (EGRF) from Caragana Jubata, a Chinese traditional Tibetan medicine. A molecularly imprinted polymer using quercetin, an active anti-EGFR inhibitor (IC50 = 15 microM), as the template and acrylamide as the functional monomer was prepared. The polymer was evaluated as a selective sorbent in molecularly imprinted solid-phase extraction. The EtOAc extract of Caragana Jubata was loaded on the polymer, and two novel active anti-EGFR inhibitors were found to be selectively retained after washing the polymer with appropriate solvent to disrupt the non-specific interactions occurring between the sample and the polymer matrix, which were identified as (E)-piceatannol (IC50 =4.9 microM) and butein (IC50 = 10 microM). The present work affords us a new potential method for selective separation of bioactive components from herb by using molecularly imprinted polymer as a solid-phase extraction adsorbent.

Simultaneous detection of oleanolic acid and ursolic acid in rat blood by in vivo microdialysis can provide important pharmacokinetics information. Microwave-assisted derivatization coupled with magnetic dispersive solid phase extraction was established for the determination of oleanolic acid and ursolic acid by liquid chromatography tandem mass spectrometry. 2'-Carbonyl-piperazine rhodamine B was first designed and synthesized as the derivatization reagent, which was easily adsorbed onto the surface of Fe3O4/graphene oxide. Simultaneous derivatization and extraction of oleanolic acid and ursolic acid were performed on Fe3O4/graphene oxide. The permanent positive charge of the derivatization reagent significantly improved the ionization efficiencies. The limits of detection were 0.025 and 0.020 ng/mL for oleanolic acid and ursolic acid, respectively. The validated method was shown to be promising for sensitive, accurate, and simultaneous determination of oleanolic acid and ursolic acid. It was used for their pharmacokinetics study in rat blood after oral administration of Arctiumlappa L. root extract.

• In situ derivatization-UADLLME was firstly reported for NTs in rat brain microdialysates. • Lissamine rhodamine B sulfonyl chloride was firstly used as derivatization reagent. • The method was simple, rapid, green, efficient, sensitive and low matrix effect. • This method was successfully applied for Parkinson’s rat brain microdialysates.<br>Simultaneous monitoring of several neurotransmitters (NTs) linked to Parkinson’s disease (PD) has important scientific significance for PD related pathology, pharmacology and drug screening. A new simple, fast and sensitive analytical method, based on in situ derivatization-ultrasound-assisted dispersive liquid-liquid microextraction (in situ DUADLLME) in a single step, has been proposed for the quantitative determination of catecholamines and their biosynthesis precursors and metabolites in rat brain microdialysates. The method involved the rapid injection of the mixture of low toxic bromobenzene (extractant) and acetonitrile (dispersant), which containing commercial Lissamine rhodamine B sulfonyl chloride (LRSC) as derivatization reagent, into the aqueous phase of sample and buffer, and the following in situ DUADLLME procedure. After centrifugation, 50 μL of the sedimented phase (bromobenzene) was directly injected for ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection in multiple reaction monitoring (MRM) mode. This interesting combination brought the advantages of speediness, simpleness, low matrix effects and high sensitivity in an effective way. Parameters of in situ DUADLLME and UHPLC-MS/MS conditions were all optimized in detail. The optimum conditions of in situ DUADLLME were found to be 30 μL of microdialysates, 150 μL of acetonitrile containing LRSC, 50 μL of bromobenzene and 800 μL of NaHCO3-Na2CO3 buffer (pH 10.5) for 3.0 min at 37 °C. Under the optimized conditions, good linearity was observed with LODs (S/N > 3) and LOQs (S/N > 10) of LRSC derivatized-NTs in the range of 0.002-0.004 and 0.007-0.015 nmol/L, respectively. It also brought good precision (3.2-12.8%, peak area CVs%), accuracy (94.2-108.6%), recovery (94.5-105.5%) and stability (3.8-8.1%, peak area CVs%) results. Moreover, LRSC derivatization significantly improved chromatographic resolution and MS detection sensitivity of NTs when compared with the reported studies through the introduction of a permanent charged moiety from LRSC into NTs. Taken together, this in situ DUADLLME method was successfully applied for the simultaneous determination of six NTs in biological samples.

AIM: Antioxidant activity is one of the important indexes for estimating medicinal value for the traditional Chinese medicine. The aim of this study is to investigate the antioxidant activity of 11 flavonoids mainly revealing luteolin as mother nucleus isolated from Pyrethrum tatsienense. MATERIALS AND METHODS: The antioxidant activity of 11 flavonoids was measured in vitro using the classical 1,1-diphenyl-2-picrylhydrazyl removal method. The percentages of scavenging activity of 11 flavonoids were analyzed by taking the choice of a-tocopherol as positive drugs, and the scavenging activity was plotted against the sample concentration to obtain the IC50 values. RESULTS: Ten flavonoids containing phenolic hydroxyl groups have different levels of antioxidant activity. Antioxidant activity mainly depends on the numbers and the substitutional positions of phenolic hydroxyls in B ring. When C-3', 4' positions in B ring of flavonoids are replaced by hydroxyl groups, the antioxidant activity improved remarkably. Phenolic hydroxyl groups in A ring contribute some to antioxidant activity because of the electrophilic effect of C ring, and the numbers and substitutional positions of methoxyl and glycosyl have a little effect on the antioxidant activity. CONCLUSION: Structure-activity relationships of antioxidant activity about flavonoids isolated from P. tatsienense are concluded, which will be beneficial to deep understanding the pharmacological functions of this Tibetan medicine in vivo from the point of antioxidation.

Objective: To study the chemical constituents of the volatile oils from the flowers of Rhododendron anthopogon D. Don.; Methods: The volatile oils from the flowers of Rhododendron anthopogon D. Don were extracted by water steam distillation and its chemical constituents were separated and identified by GC-MS. The content of each constituent was determined by area normalizetion method.; Results: Fifty peaks were separated and forty seven components were identified, which constituted about 97.44% of the total essential oils.; Conclusions: The main compounds are N-acetyl-1, 2, 3, 4-tetrahydro-isoquinoline (29.23%), 2-Ethoxypropane (12.47%), 3-Methyl-6-tert-butylphenol (10.83%), 3-Methyl-5-phenyl-isothiazole (6.38%), Diphenylamine (4.20%), N-ethyl-1, 2,3,4-tetrahydro-naphthalenamine (3.62%), Pentacosane (3.12%) and Tricosane (3.06%).;

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