Hidden Hunger of Vitamin E among Healthy College Students: A Cross- Sectional Study.

BACKGROUND: College students may have a risk of fat-soluble vitamin deficiencies due to unhealthy dietary habits, especially for vitamin A and E. They are important members of the human antioxidant network; deficiencies of these vitamins may increase the risk of many critical diseases. OBJECTIVE: The current study was undertaken to determine the status of vitamin A and E in college students. METHODS: Healthy college students were recruited, and fasting blood samples of them were collected and used for determining serum levels of retinol and α-tocopherol by the HPLC method. RESULTS: We found that there was no vitamin A deficiency in college students. However, vitamin E deficiency existed in 34.5% of college students, especially in males. All the students had no vitamin E adequacy. In addition, our findings showed that BMI was inversely associated with serum α-- tocopherol, but not serum retinol. CONCLUSION: These results suggest that vitamin E deficiency in college students should be given more attention, and it is necessary to consider using vitamin E supplements.

Repetitive transcranial magnetic stimulation as an alternative therapy for stroke with spasticity: a systematic review and meta-analysis.

Repetitive transcranial magnetic stimulation (rTMS) and intermittent theta-burst stimulation (iTBS) can be used to manage post-stroke spasticity, but a meta-analysis of the recent randomized-controlled trials (RCTs) is lacking. Our aim is to perform a meta-analysis of the RCTs that investigated the efficacy of rTMS in patients with post-stroke spasticity. PubMed, Embase, and Cochrane Library databases were searched for eligible papers published up to February 2020. The primary outcome was the Modified Ashworth Scale (MAS), measured as the effect of rTMS compared with controls and after rTMS (using a change score calculated separately in the active and sham treatment groups). Finally, five papers and eight data sets were included. rTMS had no significant benefit on MAS in patients with post-stroke spasticity compared to sham treatment (WMD = - 0.29, 95% CI - 0.58, 0.00; P = 0.051). When analyzing the change score in the treatment groups, a significant effect of rTMS was observed (WMD = - 0.27, 95% CI - 0.51, - 0.04; P = 0.024). When analyzing the change score in the sham treatment groups, no significant effect of sham treatment was observed, indicating no placebo effect (WMD = 0.32, 95% CI: - 0.40, 1.04; P = 0.387). We included the sample size, year of publication, percentage of male patients, and age difference in each study as covariates, and performed a meta-regression. The results showed no association between these variables and the MAS. Compared with sham stimulation, rTMS did not show a significant reduction in MAS for the patients who experienced post-stroke spasticity, but the patients reported a better outcome in MAS on a before-after scenario.

[Study on Triterpenoids from Helicteres angustifolia by High-Speed Countercurrent Chromatography].

Objective: To develop a method for separation and purification of triterpenoids from Helicteres angustifolia by highspeed countercurrent chromatography( HSCCC). Methods: The ethyl acetate extract of Helicteres angustifolia were separated by two-step HSCCC. The structures of the target compounds were identified by ESI-MS and1H-NMR and characterized by FTIR. Results: Six compounds were isolated and prepared from ethyl acetate extract of Helicteres angustifolia,and identified as methyl helicterilate( 1),methyl helicterate( 2),helicterilic acid( 3),helicteric acid( 4),betulic acid( 5),oleanolic acid( 6). The purity of the chemical constituents were determined by HPLC,and the mass fraction was more than 95. 0%,respectively. Conclusion: This method is suitable for the separation and preparation of triterpenoids from Helicteres angustifolia,which is rapid,high purity and high yield.

Preparative separation of quaternary ammonium alkaloids from Coptis chinensis Franch by pH-zone-refining counter-current chromatography.

pH-zone-refining counter-current chromatography was successfully applied to the preparative separation of five quaternary ammonium alkaloids from the crude extract of Coptis chinensis Franch. The separation was performed with a two-phase solvent system composed of chloroform-methanol-water (4:3:3, v/v), where the upper aqueous stationary phase was added with 60mM of hydrochloric acid and the lower organic mobile phase with 5mM of triethylamine. From 1.0 g of crude extract, 5.4 mg of columbamine at 96.6% purity, 6.1mg of jateorhizine at 98.8% purity, 58.3mg of coptisine at 99.5% purity, 25.6 mg of palmatine at 98.4% purity and 503.9 mg of berberine at 99.5% purity were obtained. The purities of the isolated alkaloids were analyzed by HPLC and the chemical structures were identified by electrospray ionization-mass spectrometry and (1)H NMR.

Preparative separation of alkaloids from Nelumbo nucifera Gaertn by pH-zone-refining counter-current chromatography.

Preparative separation of alkaloids from embryo of the seed of Nelumbo nucifera Gaertn has been successfully performed for the first time using pH-zone-refining counter-current chromatography. Two kinds of two-phase solvent systems were applied to preparative CCC isolation. The first was the system composed of MtBE-water (1:1, v/v), 10 mM triethylamine in organic stationary phase and 5 mM HCl in aqueous mobile phase, which could only separate neferine partly from the crude extract. The second was the system composed of n-hexane-ethyl acetate-methanol-water (5:5:2:8, v/v), 10 mM triethylamine in organic stationary phase and 5 mM HCl in aqueous mobile phase, which was the optimum for large-scale CCC isolation. 2.5 g of the crude alkaloid was purified in one-step separation of 7 h, yielding 151 mg of liensinine, 118 mg of isoliensinine and 572 mg of neferine with the purities of 93.0, 95.1 and 97.0%, respectively.

Preparative isolation and purification of flavonoids from the Chinese medicinal herb Belamcanda by high-speed countercurrent chromatography.

High-speed countercurrent chromatography (HSCCC) was applied for separation and purification of flavonoids from the extract of belamcanda. High efficiency of HSCCC separation was achieved on a two-phase solvent system of n-hexane-ethyl acetate-methanol-water (4:5:5:5, v/v) by eluting the lower mobile phase at a flow-rate of 1.2mL/min and a revolution speed of 800 rpm. Three well-separated peaks were obtained in the HSCCC chromatogram and their purities were determined by HPLC-UV absorption spectrometry. These peaks were characterized by ESI-MS(n) and NMR, and the data compared with the reference standards where three peaks were identified as isorhamnetin, irigenin and hispidulin. The purities of each peak were 94, 95 and 90% respectively. In HSCCC experiment, 100 mg of the crude extract were separated yielding 10 mg of isorhamnetin, 8 mg of irigenin and 7 mg of hispidulin. HSCCC thus provides a cost-effective alternative to preparative scale HPLC for the semi-preparative scale separation and purification of flavonoids from Belamcanda.

Preparative isolation and purification of rupestonic acid from the Chinese medicinal plant Artemisia rupestris L. by high-speed counter-current chromatography.

Rupestonic acid was purified for the first time by high-speed counter-current chromatography from a dichloromethane extract of the traditional Chinese medicinal plant Artemisia rupestris L. The separation was performed in two steps with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (6:4:3.5:6.5, v/v) with 0.5% acetic acid in stationary-phase. From 200 mg of the crude extract, 27.9 mg of rupestonic acid was obtained at over 98% purity as determined by HPLC analysis, and its chemical structure was confirmed by MS, 1H and 13C nuclear magnetic resonance.

Preparative isolation of osthol and xanthotoxol from Common Cnidium Fruit (Chinese traditional herb) using stepwise elution by high-speed counter-current chromatography.

Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of osthol and xanthotoxol from Cnidium monnieri (L.) Cusson (Common Cnidium Fruit) using stepwise elution with a pair of two-phase solvent systems composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v), and (5:5:6:4, v/v), which had been selected by analytical high-speed counter-current chromatography. Using a preparative unit of the HSCCC centrifuge, about a 308 mg amount of the crude extract was separated, yielding 88.3 mg of osthol and 19.4 mg of xanthotoxol at a high purity of over 98%.

Preparative separation of rhein from Chinese traditional herb by repeated high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) was repeatedly used for isolation and purification of rhein from Rheum officinale Baill (Dahuang) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (3:7:5:5, v/v), which had been selected by analytical (HSCCC). Using two preparative units of the HSCCC centrifuge, about a 500 mg amount of the crude extract was separated, yielding 6.7 mg of rhein at a high purity of over 97%.

Separation of salidroside from Rhodiola crenulata by high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) was used to purify salidroside from an extract of Rhodiola crenulata with two steps using a two-phase solvent system composed of ethyl acetate-n-butanol-water (1:4:5, v/v) in the first run and chloroform-methanol-isopropanol-water (5:6:1:4) in the second run. The method yielded 21.9 mg of salidroside from 1.216 g of the crude sample at 98% purity determined by HPLC analyses. Identification was performed by 1H NMR, 13C NMR, and MS.