Identification of Oak-Barrel and Stainless Steel Tanks with Oak Chips Aged Wines in Ningxia Based on Three-Dimensional Fluorescence Spectroscopy Combined with Chemometrics.

With the increased incidence of wine fraud, a fast and reliable method for wine certification has become a necessary prerequisite for the vigorous development of the global wine industry. In this study, a classification strategy based on three-dimensional fluorescence spectroscopy combined with chemometrics was proposed for oak-barrel and stainless steel tanks with oak chips aged wines. Principal component analysis (PCA), partial least squares analysis (PLS-DA), and Fisher discriminant analysis (FDA) were used to distinguish and evaluate the data matrix of the three-dimensional fluorescence spectra of wines. The results showed that FDA was superior to PCA and PLS-DA in classifying oak-barrel and stainless steel tanks with oak chips aged wines. As a general conclusion, three-dimensional fluorescence spectroscopy can provide valuable fingerprint information for the identification of oak-barrel and stainless steel tanks with oak chips aged wines, while the study will provide some theoretical references and standards for the quality control and quality assessment of oak-barrel aged wines.

Hyperbaric oxygen preconditioning inhibits skin flap apoptosis in a rat ischemia-reperfusion model.

BACKGROUND: Hyperbaric oxygen (HBO) improves skin flap function and inhibits partial necrosis induced by ischemia-reperfusion (I/R) injury. Our study aimed to evaluate the mechanism underlying HBO regulation of the antiapoptosis factors associated with I/R injury of skin flaps. METHODS: The rats were divided into sham surgery, I/R, and HBO groups. Rats from the HBO group received HBO preconditioning followed by I/R surgery. Blood perfusion of the skin flaps was measured with laser Doppler flowmeters. Tissue morphology and apoptosis were subsequently assessed based on hematoxylin-eosinhe and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. Protein expression of phosphorylated apoptosis signal-regulating kinase 1 (pASK-1), phosphorylated c-Jun N-terminal kinase (pJNK), B-cell lymphoma-2 (Bcl-2), and Bcl2-associated X protein (Bax) was examined by immunodetection, and Bcl-2 messenger RNA expression was detected by quantitative polymerase chain reaction. In addition, caspase-3 activity was also measured. RESULTS: The result of microcirculation analysis showed that the survival and blood perfusion rates significantly increased in the skin flap after HBO exposure. Terminal deoxynucleotidyl transferase dUTP nick-end labeling staining revealed that cell apoptosis was significantly attenuated in the HBO group. Furthermore, HBO preconditioning increased the expression of Bcl-2 and inhibited pASK-1, pJNK, and Bax expression as determined by both immunohistochemistry and Western blot. Caspase-3 activity and the Bax/Bcl-2 ratio declined in the HBO group. CONCLUSIONS: HBO preconditioning effectively ameliorates I/R injury by regulating the apoptosis signal-regulating kinase 1 and/or c-Jun N-terminal kinase pathway and anti- and proapoptosis factors.

Clinical-pathological analysis of hepatitis B virus recurrence after liver transplantation in Chinese patients.

BACKGROUND AND AIM: Liver transplantation (LT) for hepatitis B virus (HBV)-related disease can be complicated by HBV recurrence. The aim of this study was to evaluate the risk factors, prophylaxis treatment, and histological characteristics of HBV recurrence after LT when using long-term, low-dose hepatitis B immunoglobulin (HBIG) plus nucleoside analog (lamivudine [LAM] or entecavir [ETV]). METHODS: Retrospective data from 253 adult LT patients using long-term, low-dose HBIG plus nucleoside analog after LT, for a mean treatment duration of 1-72 months, were collected from a single center in Beijing, China. Univariate analyses were conducted to determine the association among gender, age, hepatocellular carcinoma, hepatitis B e antigen-positive status, HBV-DNA level and tyrosine-methionine-aspartate-aspartate (YMDD) mutations on HBV recurrence in these patients. RESULTS: Overall, the HBV recurrence rate was 6.32% (16/253). There was no significant difference in the survival rate between the HBV recurrence and non-recurrence groups. Risk factors for HBV recurrence were: hepatitis B e antigen positivity, HBV-DNA > 10(5) copies/mL, hepatocellular carcinoma, and YMDD mutation. Sixteen patients receiving LAM had HBV recurrence (16/169; mean treatment duration: 61.8 ± 18.3 months). No HBV recurrence occurred in patients receiving ETV after LT (0/84; mean treatment duration: 57.1 ± 15.9 months). Differences in rate of mortality and HBV recurrence were not significant between the two groups. CONCLUSIONS: LT is an effective treatment for HBV-related end-stage liver disease. The combination of ETV and intramuscular HBIG for HBV recurrence prophylaxis after LT was more effective than LAM, especially in Chinese patients with HBV recurrence risk factors.

Si-RNA mediated knockdown of CELF1 gene suppressed the proliferation of human lung cancer cells.

BACKGROUND: Lung cancer is the leading cause of cancer-related death in the world, with metastasis as the main reason for the mortality. CELF1 is an RNA-binding protein controlling the post-transcriptional regulation of genes related to cell survival. As yet, there is little knowledge of CELF1 expression and biological function in lung cancer. This study investigated the expression levels of CELF1 in lung cancer tissues and the biological function of CELF1 in lung cancer cells. METHODS: CELF1 mRNA expression was determined in lung cancer and normal tissues, and the relationship between the expression level of CELF1 and clinicopathological parameters was evaluated. The biological function of CELF1 in A549 and H1299 lung cancer cell lines growth was examined. RESULTS: The expression of CELF1 was higher in human lung cancer tissues compared with the normal lung tissue. Lentiviral-mediated transfection of CELF1 siRNA effectively silenced the expression of CELF1 in both A549 and H1299 cells. Moreover, CELF1 knockdown markedly reduced the survival rate of lung cancer cells. Colony formation assays revealed a reduction in the number and size of lung cancer cell colonies from CELF1 knockdown. CONCLUSION: These results indicated that CELF1 may have significant roles in the progression of lung cancer, and suggested that siRNA mediated silencing of CELF1 could be an effective tool in lung cancer treatment.

Association analysis of BclI with benign lymphoepithelial lesions of the lacrimal gland and glucocorticoids resistance.

AIM: To evaluate the relationship between gene polymorphism (BclI, ER22/23EK, N363S) and the occurrence, progression and sensitivity to glucocorticoid of lacrimal gland benign lymphoepithelial lesion (LGBLEL). METHODS: Clinical peripheral blood samples of 52 LGBLEL patients and 10 normal volunteers were collected for DNA extraction and polymerase chain reaction sequencing to analyze single nucleotide polymorphism (SNP) genotypes. The lacrimal tissues of LGBLEL were surgically removed and made into paraffin sections for subsequent hematoxylin-eosin (HE) and Masson staining analysis. The duration of disease and hormone use of LGBLEL patients from diagnosis to surgery were also analyzed. The Meta-analysis follows PRISMA guidelines to conducted a systematic review of human studies investigating the relationship between the NR3C1 BclI polymorphism and glucocorticoids (GCs) sensitivity. RESULTS: There was no association between ER22/23EK or N363S and the occurrence of LGBLEL or GCs sensitivity (P>0.05); BclI GC genotype was closely related to GCs resistance (P=0.03) as is the minor allele C (P=0.0017). The HE staining and Masson staining showed that the GC genotype of BclI remarkably slowed down the disease progression and reduced fibrosis (P<0.05), especially for GCs-dependent patients (P<0.0001). Meta-analysis showed that BclI was not significantly associated with GCs responsiveness. CONCLUSION: The LGBLEL patients who carry the NR3C1 BclI allele C may be more sensitive to GCs and associated with lower fibrosis and slower disease progression. The results may guide the clinical treatment strategy for the LGBLEL patients.

Different effects of hydrogen-rich water intake and hydrogen gas inhalation on gut microbiome and plasma metabolites of rats in health status.

The potential for preventive and therapeutic applications of H2 have now been confirmed in various disease. However, the effects of H2 on health status have not been fully elucidated. Our previous study reported changes in the body weight and 13 serum biochemical parameters during the six-month hydrogen intervention. To obtain a more comprehensive understanding of the effects of long-term hydrogen consumption, the plasma metabolome and gut microbiota were investigated in this study. Compared with the control group, 14 and 10 differential metabolites (DMs) were identified in hydrogen-rich water (HRW) and hydrogen inhalation (HI) group, respectively. Pathway enrichment analysis showed that HRW intake mainly affected starch and sucrose metabolism, and DMs in HI group were mainly enriched in arginine biosynthesis. 16S rRNA gene sequencing showed that HRW intake induced significant changes in the structure of gut microbiota, while no marked bacterial community differences was observed in HI group. HRW intake mainly induced significant increase in the abundance of Lactobacillus, Ruminococcus, Clostridium XI, and decrease in Bacteroides. HI mainly induced decreased abundances of Blautia and Paraprevotella. The metabolic function was determined by metabolic cage analysis and showed that HI decreased the voluntary intake and excretions of rats, while HRW intake did not. The results of this study provide basic data for further research on hydrogen medicine. Determination of the effects of hydrogen intervention on microbiota profiles could also shed light on identification of mechanism underlying the biological effects of molecular hydrogen.

Effect of hydrogen intervention on refractory wounds after radiotherapy: A case report.

BACKGROUND: Patients with keloids who receive radiotherapy (RT) after surgery can develop refractory wounds that cannot be healed by the patient's own repair system. Such chronic wounds are uneven and complex due to persistent abscess and ulceration. Without external intervention, they can easily result in local tissue necrosis or, in severe cases, large area tissue resection, amputation, and even death. CASE SUMMARY: This article describes the use of hydrogen to treat a 42-year-old female patient with a chronic wound on her left shoulder. The patient had a skin graft that involved implanting a dilator under the skin of her left shoulder, and then transferring excess skin from her shoulder onto scar tissue on her chest. The skin grafting was followed by two rounds of RT, after which the shoulder wound had difficulty healing. For six months, the patient was treated with 2 h of hydrogen inhalation (HI) therapy per day, in addition to application of sterile gauze on the wound and periodic debridement. We also performed one deep, large, sharp debridement to enlarge the wound area. The wound healed completely within 6 mo of beginning the HI treatment. CONCLUSION: After HI therapy, the patient showed superior progress in reepithelialization and wound repair, with eventual wound closure in 6 mo, in comparison with the previous failures of hyperbaric oxygen and recombinant bovine basic fibroblast growth factor therapies. Our work showed that HI therapy could be a new strategy for wound healing that is cleaner, more convenient, and less expensive than other therapies, as well as easily accessible for further application in clinical wound care.

Large focal nodular hyperplasia is unresponsive to arterial embolization: A case report.

BACKGROUND: Focal nodular hyperplasia (FNH) commonly occurs in women; it is usually asymptomatic and sometimes difficult to differentiate from hepatocellular carcinoma (HCC). CASE SUMMARY: A large space-occupying lesion in the right lobe of the liver was incidentally detected in an adult man and diagnosed as HCC. Transcatheter arterial chemoembolization was applied once monthly for 2 years, but the lesion did not decrease in size. It was revealed by biopsy to be FNH. Eleven years later, the patient underwent liver resection due to hemorrhage and the pathological examination confirmed FNH. CONCLUSION: For a space-occupying lesion, it is prerequisite to pathologically confirm the diagnosis and the corresponding intervention can be effective.

[Impact of S100P expression on clinical outcomes of gastric cancer patients with adjuvant chemotherapy of oxaliplatin and its mechanisms].

OBJECTIVE: To investigate the impact of the expression of S100P on the prognosis and tumor chemosensitivity in patients with resectable gastric cancer and its mechanisms. METHODS: The expression of S100P was analyzed in 121 resected primary gastric cancer tissues by using tissue array of immunohistochemistry excised from January 2003 to December 2007. The patients received adjuvant chemotherapy with oxaliplatin. The pEGFP-S100P plasmid was constructed and was transfected into BGC823 cell line to establish gastric cancer cell line with over-expression of human S100P, BGC823-S100P. The expression level of S100P was determined by real-time PCR and Western blot assay. The chemosensitivity of BGC823-S100P cell line to oxaliplatin was detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. RESULTS: The S100P was positively expressed in 64 tumors (52.9%, 64/121). Although there was no significant relation between the expression of S100P and tumor T staging (P = 0.683), N staging (P = 0.472), M staging (P = 0.770) and differentiation (P = 0.553), Wilcoxon test showed that the 5-year cumulative survival rate of patients with positive S100P expression was significantly higher than that of patients with negative expression (20.3% vs. 3.5%, P = 0.034). Furthermore, overexpressed of S100P was found in the BGC823 cell line, BGC823-S100P. The mRNA and protein level of S100P in pEGFP transfected BGC823-S100P cell lines were significantly higher than those in control group (8.42 ± 1.38 vs. 0.83 ± 0.11 and 3.52 ± 0.48 vs. 0.97 ± 0.19, all P < 0.05). It indicated with MTT assay that the half-inhibitory concentration (IC(50)) to oxaliplatin decreased in BGC823-S100P cells, and was significantly lower than that in vector-only transfected cells [(142 ± 16) mg/L vs. (266 ± 11) mg/L, P = 0.032]. CONCLUSIONS: S100P may also be a potentially novel independent prognostic factor in gastric cancer patients following curative resection. And it could improve the cumulative survival of the patients through enhancing the chemosensitivity of tumor cell line to oxaliplatin.

Hydrogen inhalation inhibits microglia activation and neuroinflammation in a rat model of traumatic brain injury.

Traumatic brain injury (TBI) is a major cause of mortality and disability worldwide. To date, therapies to treat any forms of TBI are still limited. Recent studies have demonstrated the potential neuroprotective effects of molecular hydrogen on TBI. Although it has been demonstrated that hydrogen inhalation (HI) for about 5 hrs immediately after TBI has a beneficial effect on brain injury, the most effective intervention procedure in the treatment of TBI remains unknown. The mechanism underlying the neuroprotective effects of HI on TBI also needs to be further investigated. Our results showed that inhalation of 4% hydrogen during the first day after TBI was the most effective hydrogen intervention procedure in the treatment of TBI. Pathological examination showed that HI could attenuate TBI-induced reactive astrocytosis and microglial activation. Nissl staining demonstrated a significant decrease in the number of nissl-stained dark neurons (N-DNs) in HI group compared to TBI group at 2 h post-TBI, and the TBI-induced neuronal loss was attenuated by HI at day 3 post-TBI. IHC staining showed that HI resulted a decrease in CD16-positive cells and a further increase in CD206-positive cells as compared to TBI group. Multiplex cytokine assay demonstrated the most profound regulatory effects induced by HI on the levels of IL-12, IFN-γ, and GM-CSF at 24 h post-TBI, which confirmed the inhibitory effect of hydrogen on microglia activation. We concluded that inhalation of 4% hydrogen during the first day after TBI was the most effective intervention procedure in the treatment of TBI. Our results also showed that hydrogen may exert its protective effects on TBI via inhibition of microglia activation and neuroinflammation.

Protective effects of molecular hydrogen on hepatotoxicity induced by sub-chronic exposure to chlorpyrifos in rats.

INTRODUCTION: Chlorpyrifos (CPF) is a organophosphate insecticide widely used in agriculture with attendant adverse health outcomes. Chronic exposure to CPF induces oxidative stress and elicits harmful effects, including hepatic dysfunction. Molecular hydrogen has been identified as a novel antioxidant which could selectively scavenge hydroxyl radicals. OBJECTIVE: The aim of this study was to determine whether the intake of hydrogen-rich water (HRW) could protect rats from hepatotoxicity caused by sub-chronic exposure to CPF. MATERIAL AND METHODS: Rats were treated with hydrogen-rich water by oral intake for 8 weeks. Biochemical indicators of liver function, SOD and CAT activity, GSH and MDA levels were determined by the spectrophotometric method. Liver cell damage induced by CPF was evaluated by histopathological and electron microscopy analysis. PCR array analysis was performed to investigated the effects of molecular hydrogen on the regulation of oxidative stress related genes. RESULTS: Both the hepatic function tests and histopathological analysis showed that the liver damage induced by CPF could be ameliorated by HRW intake. HRW intake also attenuated CPF induced oxidative stress, as evidenced by restored SOD activities and MDA levels. The results of PCR Array identified 12 oxidative stress-related genes differentially expressed after CPF exposure, 8 of chich, including the mitochondrial Sod2 gene, were significantly attenuated by HRW intake. The electron microscopy results indicated that the mitochondrial damage caused by CPF was alleviated after HRW treatment. CONCLUSIONS: The results obtained suggest that HRW intake can protect rats from CPF induced hepatotoxicity, and the oxidative stress signaling and the mitochondrial pathway may be involved in the protection of molecular hydrogen.

Psoralen Suppresses Cisplatin-Mediated Resistance and Induces Apoptosis of Gastric Adenocarcinoma by Disruption of the miR196a-HOXB7-HER2 Axis.

PURPOSE: The present study aimed to investigate the impact of psoralen on miR-196a-5p expression and function, and to reveal the mechanism underlying miR-196a-5p-mediated inhibition and the reversal of cisplatin (DDP) resistance. METHODS: Serum samples were collected from 50 patients with gastric cancer (GC), and the association between miR-196a-5p expression and the response to chemotherapy was assessed. A DDP-resistant GC cell line was also established to determine the effects of miR-196a-5p and psoralen on DDP resistance. MGC803 cells were transfected with miR-196a-5p mimic and inhibitor vectors for the overexpression and downregulation of miR-196a-5p, respectively. RESULTS: Clinical data analysis showed that the lower expression levels of miR-196a-5p were significantly associated with chemoresistance in patients with GC. Upregulation of miR-196a-5p significantly enhanced the anti-proliferative effect, apoptosis and sensitivity to DDP by regulating the protein expression levels of HOXB7, HER2, Bcl-2 and G1/S-specific cyclin-D1 (CCND1). Furthermore, psoralen reversed miR-196a-5p-induced DDP resistance and reduced the expression levels of HOXB7, HER2, Bcl-2 and CCND1. CONCLUSION: miR-196a-5p may be a novel biomarker of chemotherapeutic success in patients with GC and may also influence the sensitivity of GC cells to DDP. Moreover, psoralen can increase chemotherapeutic sensitivity by upregulating miR-196a-5p and then downregulating HOXB7-HER2 signaling axis.

Effects of long-term hydrogen intervention on the physiological function of rats.

The potential therapeutic effects of molecular hydrogen (H2) have now been confirmed in various human and animal-disease models. However, the effects of H2 on the physiological function in a normal state have been largely neglected. Hydrogen-rich water (HRW) intake and hydrogen inhalation (HI) are the most common used methods for hydrogen administration, the difference in the effects between HRW intake and HI remains elusive. In the present study, the body weight and 13 serum biochemical parameters were monitored during the six-month hydrogen intervention, all these parameters were significantly altered by oral intake of HRW or HI. Among the 13 parameters, the most striking alterations induced by hydrogen treatment were observed in serum myocardial enzymes spectrum. The results also showed that the changes in these parameters occurred at different time points, and the alterations in most of the parameters were much more significant in HI than HRW. The results of this study provides the basic data for the mechanism research and application of molecular hydrogen in the future.

Determination of seven flavonoids in Ixeridium gracile (DC.) Shih by high-performance liquid chromatography.

A high-performance liquid chromatographic technique coupled with photodiode array detection was proposed for the simultaneous determination of 7 flavonoids, i.e., quercetin, kaempferol, 7-hydroxyflavanone, 7-methoxyflavanone, 2',4'-dihydroxychalcone, 2',4'-dihydroxydihydrochalcone, and 7,2'-dihydroxy-3', 4'-dimethoxyisoflavane, in extracts of the plant Ixeridium gracile. Optimum separation was obtained by using a reversed-phase C18 method. Because of the different UV characteristics of these components, 5 detection wavelengths were used for the quantitative analysis. All of the flavonoids showed good linearity (r > 0.9999). The limit of detection and limit of quantitation values for the analytes ranged from 0.06 to 0.46 microg/mL and from 0.18 to 1.48 microg/mL, respectively. The method was validated by evaluating repeatability, precision, stability, and accuracy. Five different extraction and purification procedures were investigated for preparation of the sample solution. The optimized method was applied to the determination of flavonoids in I. gracile and was found to be efficient.

Molecular hydrogen suppresses glioblastoma growth via inducing the glioma stem-like cell differentiation.

BACKGROUND: Glioblastoma (GBM) is the most common type of primary malignant brain tumor. Molecular hydrogen has been considered a preventive and therapeutic medical gas in many diseases including cancer. In our study, we sought to assess the potential role of molecular hydrogen on GBM. METHODS: The in vivo studies were performed using a rat orthotopic glioma model and a mouse subcutaneous xenograft model. Animals inhaled hydrogen gas (67%) 1 h two times per day. MR imaging studies were performed to determine the tumor volume. Immunohistochemistry (IHC), immunofluorescence staining, and flow cytometry analysis were conducted to determine the expression of surface markers. Sphere formation assay was performed to assess the cancer stem cell self-renewal capacity. Assays for cell migration, invasion, and colony formation were conducted. RESULTS: The in vivo study showed that hydrogen inhalation could effectively suppress GBM tumor growth and prolong the survival of mice with GBM. IHC and immunofluorescence staining demonstrated that hydrogen treatment markedly downregulated the expression of markers involved in stemness (CD133, Nestin), proliferation (ki67), and angiogenesis (CD34) and also upregulated GFAP expression, a marker of differentiation. Similar results were obtained in the in vitro studies. The sphere-forming ability of glioma cells was also suppressed by hydrogen treatment. Moreover, hydrogen treatment also suppressed the migration, invasion, and colony-forming ability of glioma cells. CONCLUSIONS: Together, these results indicated that molecular hydrogen may serve as a potential anti-tumor agent in the treatment of GBM.

Human Umbilical Cord Mesenchymal Stem Cells Therapy for Insulin Resistance: A Novel Strategy in Clinical Implication.

There is increasing evidence reporting that as a common phenomenon in MetS relative diseases, insulin resistance (IR) is regarded as an independent etiological factor and a warning indicator of MetS occurrence. Therefore, for the special group (overweight or obesity), clinical regular monitoring of IR is an important basis for the prevention and early intervention of MetS relative diseases. This surveys reveals that human umbilical cord mesenchymal stem cells (HUC-MSCs)possess a kind of potential: it may become a possible theraphy for IR in type 2 diabetes mellitus (T2DM) and related diseases. Specific emphasis is focused on evaluating the improvement IR function of HUC-MSCs under the background of development in vitro and in vivo. Next, the action mechanisms of HUC-MSCs is discussed, and some of their advantages and disadvantages in the course of clinic application are presented. The final section highlights the application of HUC-MSCs in T2DM and relative diseases at this stage. Up to now, although many questions remain unresolved, we still consider that HUC-MSCs is one of the best therapy ameliorating IR in the future.

IgG4 and IgE co-positive group found in idiopathic orbital inflammatory disease.

AIM: To reveal the cytokines involved in idiopathic orbital inflammatory disease (IOID) and the relationship between Th17 cells, IgE and IOID pathogenesis. METHODS: Whole blood samples were processed immediately after collection and serological IgG4, IgG, and IgE antibodies were tested using ELISA. IOID and orbital cavernous hemangioma (CH) tissue samples underwent Bio-Plex multiplex cytokine detection. Hematoxylin-Eosin (HE) staining of all paraffin samples suggested the histological features of IOIDs, and expressions of IgG4 and IL-17A in affected tissues were detected by immunohistochemistry. RESULTS: Among 40 IOID plasma samples, 52.5% (21/40) were positive for IgG4 and 25% (10/40) were positive for IgE. Overlapped IgG4 or IgE positive samples accounted for 22.5% (9/40). Therefore, IOID samples were separated into three groups. The IgE+/IgG4+ group had a relevantly lower level of pro-inflammatory cytokine expression. IL-4 (Th2 cell related), IL-10 and TGF-ß1 (Treg cell immunity related) were elevated in all three groups. Some of the Th17 cell related cytokines (i.e. IL-17A/F, IL-25, IL-23, and IL-33) displayed higher expression levels in the IgE-/IgG4- group compared to the other two groups. CONCLUSION: We discovered an IgG4-IgE co-positive group as well as Th17 cell immune involvement in IgG4-IgE co-negative subgtroup in IOID for the first time. The pathogenesis of IOID could differ from different subgroups according to the IgG4 and IgE detection. Therefore, we recommend that, Treatment stratagy should be made according to the clinical assessment of IgG4-IgE and Th17 profile detection.

Simultaneous determination of flavonoids in Ixeridium gracile by micellar electrokinetic chromatography.

A micellar electrokinetic chromatography (MEKC) method has been developed for the quantitative analysis of five flavonoids: luteolin 7-O-glucoside (LG), 2',4'-dihydroxy-dihydrochalcone (DD), 2',4'-dihydroxy-chalcone (DC), 7-hydroxy-flavanone (HF) and quercetin 3-O-galactoside (QG) in Ixeridium gracile with UV detection at 275 nm. The applied voltage was 25 kV and the capillary temperature was kept constant at 25 degrees C. The effects of buffer pH, the concentration of electrolyte and organic modifier on migration behavior were studied. Optimum separation condition was achieved with 15 mM borate, 30 mM sodium dodecyl sulfate (SDS) and 10% (v/v) ethanol at pH 10.5. Regression equations showed good linear relationships (correlation coefficients: 0.9984, 0.9991, 0.9994, 0.9995 and 0.9997) between the peak area of each compound and their concentrations. The relative standard deviations (R.S.D.) of the migration time and peak area were less 1.67 and 3.53% (intra-day), and 1.82 and 3.73% (inter-day), respectively, under the optimum separation conditions. The contents of the five active compounds in I. gracile were determined with satisfactory repeatability and recovery.

Phenolic derivatives with free-radical-scavenging activities from Ixeridium gracile (DC.) Shih.

Phytochemical investigation of the Tibetan medicinal plant Ixeridium gracile resulted in the isolation and identification of twelve flavonoids and two coumarins, compounds 1-14, the dimeric '2alpha,3alpha-epoxy-5,7,3',4'-tetrahydroxyflavan-(4beta-->8)-epicatechin' (1) being a new constituent. The free-radical-scavenging potentials of different extract fractions as well as of the pure compounds towards the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical were evaluated, and are discussed in terms of structure-activity relationship (SAR). The flavonoids were found to be the major constituents contributing to the free-radical-scavenging activity of I. gracile, but the high concentration of coumarins additionally contributed to the observed activity.