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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.

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.

The eco-environment in eastern part of Qinghai-Tibet plateau is a rather complicated complex. The plants species there are quite diverse. The plant resource from Polygonaceae family used in traditional Tibetan medicine is very rich according to preliminary investigation. There were 6 genera and 15 species. The flora and the medicine value of them were analyzed. And some suggestions about traditional Tibetan medicine plant resource exploitation and utilization were presented.

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.

Traditional Tibetan medicine is important for discovery of drug precursors. However, knowledge of the chemical composition of traditional Tibetan medicines is very limited due to the lack of appropriate chromatographic purification methods. In the present work, Salvia prattii was taken as an example, and an off-line hydrophilic interaction liquid chromatography/reversed-phase liquid chromatography preparative method was developed for the purification of phenylpropanoids with high purity from a crude sample of Salvia prattii. Based on the separation results of four different chromatographic stationary phases, the first-dimensional preparation was performed on an XAmide preparative column with the crude sample concentration of 62.0 mg/mL, and five main fractions were obtained from the 12.4 g crude sample with a recovery of 54.8%. An XCharge C18 preparative column was applied in the second-dimensional preparation to further isolate the phenylpropanoids from the redissolved first-dimensional fractions with concentration of approximately 50.0 mg/mL. The purities of the phenylpropanoids isolated from the crude sample of Salvia prattii were higher than 98%, indicating that the method was efficient for the purification of phenylpropanoids with high purity from Salvia prattii. Additionally, this method showed great potential in the preparation of phenylpropanoids and can serve as a good example for the purification of phenylpropanoids from other plant materials.

From the whole plant of <i>Morina nepalensis</i> var. <i>alba</i> Hand.-Mazz., two new acylated flavonoid glycosides (<b>1</b> and <b>2</b>), together with four known flavonoid glycosides (<b>3-6</b>), were isolated. Their structures were determined to be quercetin 3-<i>O</i>-[2″′-<i>O</i>-(<i>E</i>)-caffeoyl]-α-L-arabinopyranosyl-(1→6)-β-D-galactopyranoside (monepalin A, <b>1</b>), quercetin 3-<i>O</i>-[2″′-<i>O</i>-(<i>E</i>)-caffeoyl]-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (monepalin B, <b>2</b>), quercetin 3-<i>O</i>-α-L-arabinopyranosyl-(1→6)-β-D-galactopyranoside (rumarin, <b>3</b>), quercetin 3-<i>O</i>-β-D-galactopyranoside (<b>4</b>), quercetin 3-<i>O</i>-β-D-glucopyranoside (<b>5</b>) and apigenin 4<sup>′</sup>-<i>O</i>-β-D-glucopyranoside (<b>6</b>). Their structures were determined on the basis of chemical and spectroscopic evidence. Complete assignments of the ¹H and <sup>13</sup>C NMR spectra of all compounds were achieved from the 2D NMR spectra, including H-H COSY, HMQC, HMBC and 2D HMQC-TOCSY spectra. Copyright © 2002 John Wiley & Sons, Ltd.

Bioassay-guided fractionation of the ethanol extract of the aerial parts of Clematis tangutica led to the isolation of two new antifungal triterpene saponins. Their structures were determined to be 3- O-alpha- L-arabinopyranosyl hederagenin 28- O-alpha- L-rhamnopyranosyl ester ( 1) and 3- O-beta- D-glucopyranosyl-(1--> 4)-alpha- L-arabinopyranosyl hederagenin 28- O-alpha- L-rhamnopyranosyl ester ( 2) on the basis of spectral data and chemical evidence. Inhibitory activities of the two saponins against seven fungal strains were evaluated. Compounds 1 and 2 showed evident antifungal activity (MIA approximately 2.5 micrograms/disc) against Saccharomyces cerevisiae, similar to the positive control amphotericin B and ordinary activities (MIA approximately 10 micrograms/disc) against Penicillium avellaneum UC-4376, Candida glabrata, Trichosporon beigelii and Pyricularia oryzae. Compound 2 is a better antifungal agent than compound 1 against most of the fungal strains that were tested.;

Two new iridoid glycosides designated as senburiside III (2) and senburiside IV (3), together with one known iridoid glycoside senburiside I (1) and three known secoiridoid glucosides swertiamarin (4), gentiopicroside (5) and sweroside (6), were isolated from the whole plant of Swertia franchetiana. The structures of the two new compounds were elucidated by spectroscopic methods.;

<br>Display Omitted<br>• Two new stilbenoid derivatives were isolated from <b>Sphaerophysa salsula</b>. • One compound were isolated for the first time from this species. • Eight known compounds were isolated from the plant. • These compounds enriched the structural types of natural products from <b>Sphaerophysa salsula</b>.<br>Two new compounds, gnetuhainins Fa (<b>1</b>) and cassigarols Ea (<b>2</b>), were isolated from the whole herb of <b>Sphaerophysa salsula</b> along with eight known compounds (<b>3</b>-<b>10</b>). The compounds (<b>4</b>) were isolated for the first time from this species. Their structures were elucidated by ESI-MS, UV, IR, 1D NMR and 2D NMR data.

Nitrogen (N) status has a great impact on methane (CH4) consumption by soils. Modeling studies predicting soil CH4 consumption assume a linear relationship between CH4 uptake and N addition rate. Here, we present evidence that a nonlinear relationship may better characterize changes in soil CH4 uptake with increasing N additions. By conducting a field experiment with eight N-input levels in a Tibetan alpine steppe, we observed a unimodal relationship; CH4 uptake increased at low to medium N levels but declined at high N levels. Environmental and microbial properties jointly determined this response pattern. The generality of the unimodal trend was further validated by two independent analyses: (i) we examined soil CH4 uptake across at least five N-input levels in upland ecosystems across China. A unimodal CH4 uptake-N addition rate relationship was observed in 3 out of 4 cases; and (ii) we performed a meta-analysis to explore the N-induced changes in soil CH4 uptake with increasing N additions across global upland ecosystems. Results showed that the changes in CH4 uptake exhibited a quadratic correlation with N addition rate. Overall, we suggest that the unimodal relationship should be considered in biogeochemistry models for accurately predicting soil CH4 consumption under global N enrichment.

Mindfulness reduces eating disorder (ED) psychopathology. Self-compassion is a related but distinct construct that may predict other clinical outcomes more strongly than does mindfulness. Previous evidence suggests that self-compassion is associated with less ED psychopathology, although no studies have compared the unique effects of self-compassion and mindfulness. Moreover, few studies have explored mechanisms of this association. The current survey study explored the unique association between self-compassion and ED psychopathology, controlling for mindfulness, as well as whether depressive rumination mediates this association. One hundred and ninety undergraduates completed questionnaires assessing self-compassion, mindfulness, depressive rumination, and ED psychopathology at baseline and five months later. In cross-sectional and longitudinal analyses, self-compassion predicted ED psychopathology even when controlling for mindfulness. By contrast, mindfulness did not predict ED psychopathology when controlling for self-compassion. Depressive rumination mediated the unique association between self-compassion and ED psychopathology in cross-sectional but not longitudinal analyses. The current findings suggest that self-compassion may be a more proximal predictor of ED psychopathology than is mindfulness. Additional research will need to further explore whether depressive rumination is a mechanism of this effect.

AIMS OF THE STUDY: Meconopsis quintuplinervia, a medicinal herb endemic to the Tibetan region, is used to treat hepatitis. The aim of this study is to evaluate the antioxidant potential of the ethanolic extract of this herb using different assays.MATERIALS AND METHODS: The antioxidant capacity of Meconopsis quintuplinervia was investigated using various established in vitro systems. An in vivo study of carbon tetrachloride (CCl(4))-induced antioxidant activity in mice was also conducted by examining the levels of malondialdehyde (MDA) and the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). RESULTS: The extract showed strong in vitro antioxidant ability. In the in vivo study, CCl(4)-induced oxidative stress caused significant decreases in the SOD, CAT, and GSH levels and a significant increase in the MDA level, most of which were significantly reversed (except for SOD in the liver.) by treatment with the extract and standard Vitamin E. CONCLUSION: This study clearly indicates that the ethanolic extract of Meconopsis quintuplinervia is a valuable source of natural antioxidants. These findings provide scientific support for the traditional use of this herb as a Tibetan medicine for liver diseases.

ETHNOPHARMACOLOGICAL RELEVANCE: Swertia chirayita, a medicinal herb endemic to the Tibetan region, is used as a special remedy for liver disorders. The hepatoprotective activity of its plant extracts has been associated with its antioxidant activity. This paper aims to investigate the in vitro and in vivo antioxidant effects of Swertia chirayita extracts (SCE).MATERIALS AND METHODS: Antioxidant ability of Swertia chirayita was investigated by employing several established in vitro methods. In vivo antioxidant activity was tested against CCl(4)-induced toxicity in mice. The levels and activities of malondialdehyde (MDA) and antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), were then assayed using standard procedures. RESULTS: SCE exhibited strong antioxidant ability in vitro. The liver and kidney of CCl(4)-intoxicated animals exhibited a significant (p<0.001) decrease in SOD, CAT, and GSH levels. Additionally, these organs exhibited a significant (p<0.001) increase in MDA level. CCl(4) did not exhibit toxicity on mice treated with SCE and Vitamin E. The effects of Swertia chirayita (three dosages) were comparable to those of Vitamin E, except in MDA level in the liver and GSH level in the kidney (p<0.05). CONCLUSION: This study suggests that the ethanolic extract of Swertia chirayita possesses in vitro and in vivo antioxidant effects. This supports the traditional use of Swertia chirayita in Tibetan medicine to cure liver diseases.

Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.

Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.

AIM: The objective of this study was to evaluate the effects of seed oil of Caragana korshinskii Kom. against Trichophyton mentagrophytes on an in vivo guinea pig model of dermatophytosis.METHODS: The skin of albino guinea pigs was infected with T. mentagrophytes, and the animals were divided into five groups: negative control (NC group), positive control (PC group), vehicle control, CK50% group (received topical 50% seed oil of C.korshinskii), and CK100% group (received topical 100% seed oil of C.korshinskii). Evaluation of clinical efficacy was performed 72 h after the completion of a 10-day treatment regimen. Skin biopsy samples were processed for histopathological examination. RESULTS: The infected untreated control guinea pigs showed patches of hair loss and ulcerated or scaly skin. Lower clinical scores indicate improved efficacy compared with NC. The lesion scores significantly declined in the CK50%, CK100%, and PC groups in comparison with the NC group. The CK50% group (45.31%) and the CK100% group (75%) showed clinical efficacy compared with the PC group (78.13%). In addition, no fungal elements, inflammation, or tissue destruction was observed in any of the PAS-stained sections of the infected skin in the groups treated with CK100% or 1% terbinafine. CONCLUSION: Seed oil of C.korshinskii demonstrated high antifungal efficacy in experimental dermatophytosis.

AIM: The objective of this study was to evaluate the effects of seed oil of Caragana korshinskii Kom. against Trichophyton mentagrophytes on an in vivo guinea pig model of dermatophytosis. METHODS: The skin of albino guinea pigs was infected with T. mentagrophytes, and the animals were divided into five groups: negative control (NC group), positive control (PC group), vehicle control, CK50% group (received topical 50% seed oil of C.korshinskii), and CK100% group (received topical 100% seed oil of C.korshinskii). Evaluation of clinical efficacy was performed 72 h after the completion of a 10-day treatment regimen. Skin biopsy samples were processed for histopathological examination. RESULTS: The infected untreated control guinea pigs showed patches of hair loss and ulcerated or scaly skin. Lower clinical scores indicate improved efficacy compared with NC. The lesion scores significantly declined in the CK50%, CK100%, and PC groups in comparison with the NC group. The CK50% group (45.31%) and the CK100% group (75%) showed clinical efficacy compared with the PC group (78.13%). In addition, no fungal elements, inflammation, or tissue destruction was observed in any of the PAS-stained sections of the infected skin in the groups treated with CK100% or 1% terbinafine. CONCLUSION: Seed oil of C.korshinskii demonstrated high antifungal efficacy in experimental dermatophytosis.

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.

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.

Wearable medical devices have enabled unobtrusive monitoring of vital signs and emerging biofeedback services in a pervasive manner. This article describes a wearable respiratory biofeedback system based on a generalized body sensor network (BSN) platform. The compact BSN platform was tailored for the strong requirements of overall system optimizations. A waist-worn biofeedback device was designed using the BSN. Extensive bench tests have shown that the generalized BSN worked as intended. In-situ experiments with 22 subjects indicated that the biofeedback device was discreet, easy to wear, and capable of offering wearable respiratory trainings. Pilot studies on wearable training patterns and resultant heart rate variability suggested that paced respirations at abdominal level and with identical inhaling/exhaling ratio were more appropriate for decreasing sympathetic arousal and increasing parasympathetic activities.

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