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Feng Huang

Publications and source records attributed to Feng Huang.

At least 37 records · Page 2Linked to original sources
PubMed2006

A new triterpene and dibenzocyclooctadiene lignans from Schisandra propinqua (WALL.) BAILL.

A new triterpene and two new natural dibenzocyclooctadiene lignans were isolated from the stems of Schisandra propinqua. In addition, three known lignans, octadecanoic acid, 2,3-dihydroxypropyl ester and beta-sitosterol were isolated. The structures of the new triterpene and new natural products were elucidated base on spectral analysis, including 1D and 2D NMR experiments. The isolates were tested for their cytotoxic effects against several tumor cell lines by MTT assay.

Antineoplastic Agents, Phytogenic↗
PubMed2006

Bone marrow angiogenesis in aplastic anemia.

The objective of this study was to investigate the status of bone marrow angiogenesis in aplastic anemia (AA). Bone marrow specimens from 32 patients with AA and 16 normal controls were studied. The number of bone marrow microvessels was examined by means of immunohistochemical staining for CD34. Determination of microvessel density (MVD) and angiogenesis grading were done in a blinded manner. The results showed that the bone marrow MVD in patients with AA was significantly lower than that in healthy subjects (P < 0.01). MVD in patients with severe and moderate AA was lower than that in control group, respectively (P < 0. 01). There is significant MVD difference between severe AA and moderate AA (P < 0.05). Angiogenesis grade and MVD in AA were positively correlated (r = 0.64, P < 0.01). It is concluded that bone marrow angiogenesis in AA patients is lower than that in normal controls. Defect of angiogenesis in bone marrow may play a role resulting in or aggravating hematopoietic aplasia in patients with AA.

Adult↗
PubMed2006

[A short-term efficacy and safety study of infliximab in active ankylosing spondylitis].

OBJECTIVE: To evaluate the efficacy and safety profile of a loading regimen of the anti-TNFalpha antibody infliximab in ankylosing spondylitis (AS). METHODS: This was an open-labeled trial. Subjects eligible for this study were adults with a diagnosis of definite AS. Active disease was a Bath AS disease activity index (BASDAI) > or = 4 and spinal pain VAS > or = 4. Concurrent stable treatment with nonsteroidal anti-inflammatory drugs was permitted during the study. Subjects were not permitted to be on methotrexate, systemic corticosteroids, cytotoxic drugs or disease-modifying anti-rheumatic drugs for various time periods before screening. Infliximab 5 mg/kg was infused at weeks 0, 2, 6. All patients were followed up to 10 weeks. The primary endpoint was proportion of ASAS 20 responders at week 10. The secondary endpoints were the proportion of subjects achieving an ASAS partial remission, the change from baseline in bath AS functional index and in the physical component summary score of the short form-36 in health survey questionnaire at week 10. Other secondary endpoints, related to reducing signs and symptoms of AS and improving range of motion and physical function, were evaluated. RESULTS: 63 patients (79% males, 90% HLA-B(27)(+), median age 32 yr, median disease duration 10 yr) completed the treatment. The proportion of ASAS 20 responders at 2, 6, 10 week was 75%, 84%, 84% respectively. The proportion of ASAS partial remission patients at 2, 6, 10 week was 10%, 21%, 30% respectively. Results for other secondary efficacy endpoints showed that infliximab could provide substantial benefits to patients with AS by reducing clinical signs and symptoms and improving range of motion, physical function, and quality of life. Sixty-five percent of subjects reported treatment-related adverse events. The most frequently occurred were upper respiratory tract infection and skin and appendages. Secondary was elevation of liver enzymes. Most treatment-related adverse events were mild to moderate in severity. Two patients had serious dermatitis and one stopped treatment owing to an infusion reaction. Short-term follow up indicated that effect of Remicade lasted for about 2 to 8 months without any new side effect. CONCLUSION: A loading regimen of infliximab demonstrated consistent evidence of efficacy and was well tolerated in the treatment of active AS.

Adolescent↗
PubMed2006

[Review of bioactivities of natural cycloartane triterpenoids].

Cycloartane triterpenoids, which exist widely in nature, are mainly distributed in Astragalus (Leguminosae) species, Trib. Cimicifuga (Ranunculaceae) and Thalictrium (Ranunculaceae) species and possess various bioactivities. Along with the development of isolation techniques of phytochemistry, more and more this kind of compounds are isolated and identified. However, bioactivity researches on the compounds are relatively lagged behind. Most researches are still in screening level, deficient in mechanism elucidation, short of action proven in vivo and SAR analysis. The author summarized the bioactivity of this kind of compounds from all aspects: anti-tumor, anti-virus, antibacterial, anti-inflammation, immune-regulatory, cardiovascular system, hepatic protection and so forth. This will be benefit for the further research and development of the compounds.

Animals↗
PubMed2006

Evaluation of efficacy and safety of diacerein in knee osteoarthritis in Chinese patients.

OBJECTIVE: To evaluate the efficacy and safety of diacerein in patients with knee osteoarthritis (OA). METHODS: A total of 223 patients satisfying the American College of Rheumatology criteria for knee OA were chosen for this 17-week, randomized, double-dummy, diclofenac sodium-controlled trial, with diacerein dosage of 100 mg/d and diclofenac sodium of 75mg/d. Efficacy and safety of both drugs were evaluated. RESULTS: Totally 106 patients in the diacerein group and 107 patients in the diclofenac group were considered qualified for the evaluation. After 12 weeks of treatment, the total effective rates of patients/physicians' overall assessment in diacerein and diclofenac groups were 65.4%/61.6% and 61.2%/61.2%, respectively (P > 0.05). The primary efficacy parameter [visual analog scale (VAS) assessment of pain on 20 metres walking] and the secondary efficacy parameters [tenderness on palpation, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and 36-item Short-Form (SF-36) Health Survey] significantly improved compared with baseline in both groups (P < 0.05). In the follow-up period, there were no obvious changes in above parameters in diacerein group. However, in diclofenac group, pain on 20 metres walking, tenderness on palpation, and WOMAC became aggravated after withdrawing the drug for 4 weeks (P < 0.05). Moreover, the consumption of paracetamol was significantly lower in diacerein group than in diclofenac group during follow-up (P < 0. 001). The incidences of related adverse events were 35.7% in diacerein and 45.1% in diclofenac group, respectively. Mild-to-moderate gastrointestinal disorders were the most frequent adverse events. CONCLUSIONS: Diacerein is as effective as diclofenac sodium in treating patients with knee OA. Furthermore, it has better extended effect and a good safety profile. It is generally well tolerated and has no severe adverse effect.

Adult↗
PubMed2005

The cytotoxicity of naturally occurring styryl lactones.

We extracted and isolated three natural styryl lactones from Goniothalamus griffithii Hook f. Thoms and investigated their cytotoxicity on a panel of three hepatocyte cell lines, HepG2, drug resistant HepG2 (HepG2-R) and primary cultured normal mice hepatocyte in order to find candidates of potential anti-cancer drugs which have low toxicity on normal cells and high effect on tumors or drug resistant tumors. All the three styryl lactones showed evident cytotoxic activities on both HepG2 and HepG2-R cell lines; however, gonithalamin and goniodiol shows less toxicity on normal mice hepatocyte as the IC(50) values of them on normal mice hepatocyte were about three times of that on HepG2. Morphological observation and cell cycle analysis were employed to elucidate the mechanisms of cytotoxicity of the tested compounds. Many apoptotic cells were observed in gonithalamin- and altholactone-treated cells, whereas, cells with chromosomes gathered at the equator were easily found in goniodiol-treated cultures. The analysis of cell cycle showed that G(2)/M arrest contributed to goniothalimin- and gonidiol-caused cell death and apoptosis was the cause of gonithalamin- and altholactone-induced cell death. Our results suggest that the three styryl lactones may be prospectively developed into anti-tumor drugs, especially on treating drug-resistance tumor after structure modification.

Animals↗
PubMed2005

Size-dependent phase transformation kinetics in nanocrystalline ZnS.

Nanocrystalline ZnS was coarsened under hydrothermal conditions to investigate the effect of particle size on phase transformation kinetics. Although bulk wurtzite is metastable relative to sphalerite below 1020 degrees C at low pressure, sphalerite transforms to wurtzite at 225 degrees C in the hydrothermal experiments. This indicates that nanocrystalline wurtzite is stable at low temperature. High-resolution transmission electron microscope data indicate there are no pure wurtzite particles in the coarsened samples and that wurtzite only grows on the surface of coarsened sphalerite particles. Crystal growth of wurtzite stops when the diameter of the sphalerite-wurtzite interface reaches approximately 22 nm. We infer that crystal growth of wurtzite is kinetically controlled by the radius of the sphalerite-wurtzite interface. A new phase transformation kinetic model based on collective movement of atoms across the interface is developed to explain the experimental results.

Journal Article↗
PubMed2005

Application of partial differential equation-based inpainting on sensitivity maps.

Inpainting is an image interpolation method. Partial differential equation (PDE)-based digital inpainting techniques are finding broad applications. In this paper, PDE-based inpainting techniques are applied to the field of MR parallel imaging. A novel model and its corresponding numerical method are introduced. This model is then applied to sensitivity maps. Coil sensitivity maps are important for parallel imaging, and they often require extrapolation and hole filling (holes being dark regions of low signal in MR images). These problems can be solved simultaneously by the application of inpainting techniques. Experiments for determining coil sensitivity maps for phantoms and cardiac MR images demonstrate the accuracy of the proposed model. Images generated using sensitivity encoding (SENSE) that utilizes inpainted sensitivity maps, thin-plate spline (TPS) estimated sensitivity maps, and Gaussian kernel smoothed (GKS) sensitivity maps are compared. From the experimental results, it can be seen that inpainted sensitivity maps produce better results than GKS sensitivity maps. The TPS method generates results similar to those of the inpainting technique but is much more time-consuming.

Algorithms↗
PubMed2005

k-t GRAPPA: a k-space implementation for dynamic MRI with high reduction factor.

A novel technique called "k-t GRAPPA" is introduced for the acceleration of dynamic magnetic resonance imaging. Dynamic magnetic resonance images have significant signal correlations in k-space and time dimension. Hence, it is feasible to acquire only a reduced amount of data and recover the missing portion afterward. Generalized autocalibrating partially parallel acquisitions (GRAPPA), as an important parallel imaging technique, linearly interpolates the missing data in k-space. In this work, it is shown that the idea of GRAPPA can also be applied in k-t space to take advantage of the correlations and interpolate the missing data in k-t space. For this method, no training data, filters, additional parameters, or sensitivity maps are necessary, and it is applicable for either single or multiple receiver coils. The signal correlation is locally derived from the acquired data. In this work, the k-t GRAPPA technique is compared with our implementation of GRAPPA, TGRAPPA, and sliding window reconstructions, as described in Methods. The experimental results manifest that k-t GRAPPA generates high spatial resolution reconstruction without significant loss of temporal resolution when the reduction factor is as high as 4. When the reduction factor becomes higher, there might be a noticeable loss of temporal resolution since k-t GRAPPA uses temporal interpolation. Images reconstructed using k-t GRAPPA have less residue/folding artifacts than those reconstructed by sliding window, much less noise than those reconstructed by GRAPPA, and wider temporal bandwidth than those reconstructed by GRAPPA with residual k-space. k-t GRAPPA is applicable to a wide range of dynamic imaging applications and is not limited to imaging parts with quasi-periodic motion. Since only local information is used for reconstruction, k-t GRAPPA is also preferred for applications requiring real time reconstruction, such as monitoring interventional MRI.

Algorithms↗
PubMed2005

A variational PDE based level set method for a simultaneous segmentation and non-rigid registration.

A new variational PDE based level set method for a simultaneous image segmentation and non-rigid registration using prior shape and intensity information is presented. The segmentation is obtained by finding a non-rigid registration to the prior shape. The non-rigid registration consists of both a global rigid transformation and a local non-rigid deformation. In this model, a prior shape is used as an initial contour which leads to decrease the numerical calculation time. The model is tested against two chamber end systolic ultrasound images from thirteen human patients. The experimental results provide preliminary evidence of the effectiveness of the model in detecting the boundaries of the incompletely resolved objects which were plagued by noise, dropout, and artifact.

Algorithms↗
PubMed2005

Xanthones from the roots of Polygala caudata and their antioxidation and vasodilatation activities in vitro.

Three new xanthones, 2-hydroxy-1,6,7-trimethoxyxanthone (1), 1,4-dimethoxy-2,3-methylenedioxyxanthone (2), and 7-hydroxy-1,2-dimethoxyxanthone (3), together with five known compounds, 2,7-dihydroxy-1-methoxyxanthone (4), 1-methoxy-2,3-methylenedioxyxanthone (5), 7-hydroxy-1-methoxyxanthone (6), euxanthone (1,7-dihydroxyxanthone) (7), and gentitein (1,3,7-trihydroxyxanthone) (8), were isolated from the roots of Polygala caudata. Their structures were established on the basis of spectral evidence. In the antioxidation activity screening in vitro with luminol chemiluminescence methods, compounds 1 - 5 and 7 and 8 showed H2O2 scavenger activity, with a scavenging effect of 58.4 - 94.5% at 10 microg/mL, and 26.0 - 84.7% at 2 microg/mL. Compounds 4 and 8 also exhibited scavenging effects on the reactive oxygen free radicals produced by macrophage respiratory bursts, with a scavenging effect of 71.7% and 63.4% at 10 microg/mL, 41.2% and 47.8% at 2 microg/mL, respectively. In the vasodilatation assay, compounds 4 - 7 exhibited relaxing activity on the contractions evoked by KCl in Wistar rat thoracic aorta rings in a dose-dependent manner.

Animals↗
PubMed2005

[Effect of ginsenoside Rg1 on neprilysin expression induced by LPS in SK-N-SH cell line].

OBJECTIVE: To investigate the effect of ginsenoside Rg1 on the neprilysin (NeP) expression induced by LPS in SK-N-SH cell line. METHODS: MTT was used to measure the survival rate of SK-N-SH cultured with ginsenoside Rg1 at different concentrations (5, 10, 20 micromol/L) and LPS (50 mg/L). The expression of NEP was measured by RT-PCR. RESULT: The survival rate of SK-N-SH was obviously inhibited by LPS, the expression of NEP was decreased. On the other hand, the above alteration induced by LPS was reversed by ginsenoside Rg1. CONCLUSION: This study demonstrates that LPS can cause cell damage and the decrease of NEP expression. Ginsenoside Rg1 can protect SK-N-SH cells against the injury induced by LPS, increase NEP expression.

Cell Line, Tumor↗
PubMed2005

[Inhibition of proliferation and induction of apoptosis by tanshinone II A in NCI-H460 cell].

OBJECTIVE: To investigate the inhibition of tanshinone II A in NCI-H460 cell line and its mechanism. METHODS: MTT was used to measure the levels of the proliferation of NCI-H460 cultured with tanshinone II A in different concentrations. The effects of tanshinone II A on cell cycle of NCI-H460 were observed by FCM. After treated with tanshinone II A for 48h, the level of mRNA of bcl-2 and C-myc in NCI-H460 was tested by RT-PCR method. RESULT: The proliferation of NCI-H460 was obviously inhibited by tanshinone II A in a dose dependent manner. The outcome of FCM showed that the apoptotic cell rate was 1.2%, 3.4%, 7.7% respectively, when cultured with tanshinone II A at 0.5 microg/ml for 24, 48, 72 h. The apoptotic cell rate was 2.6%, 5.9%, 13.4%, when cultured with tanshinone II A at 1.0 microg/ml for 24, 48, 72 h. The apoptotic cell rate was 4.1%, 8.7%, 37.6%, when cultured with tanshinone II A at 2.0 microg/ml for 24, 48, 72 h. The outcome of RT-PCR showed that the expression of proto-onco gene bcl-2 and C-myc was notably decrease, after cultured with tanshinone II A for 48 h. CONCLUSION: Tanshinone IIA can inhibit the proliferation of NCI-H460 and induce the apoptosis of the cell.

Abietanes↗
PubMed2005

[Effects of benefiting-bone capsule on the expression of transforming growth factor-beta1 mRNA in bone tissue of the ovariectomized rats].

OBJECTIVE: To investigate the effects of Benefiting-bone capsule (BBC) on the expression of transforming growth factor-beta1 mRNA in bone tissue of the ovariectomized rats to further explain the mechanism of BBC on preventing and treating osteopoprosis. METHODS: Twenty-four rats were randomly chosen from 72 female SD rats aged 10 months, which were classified into group A and B of sham operation dealing with normal physiological saline. The left 48 rats were randomly divided into 4 groups after ovariectomy: group A and B of osteoporotic animal model with normal physiological saline, prevented and treated groups of osteoporotic animal model with BBC. Each group included 12 rats. Ovariectomy was used to establish the osteoporotic animal model and the expression of TGF-beta1 mRNA on gene level in bone tissue was detected by real time fluorescence quantitative PCR (FQ-PCR) method. RESULTS: The expression of TGF-beta1 mRNA on gene level in bone tissue of the groups of osteoporotic animal model with BBC were all higher than that of the groups of osteoporotic animal model, which were close to the groups of sham operation. CONCLUSION: BBC can improve the expression of TGF-beta1 mRNA on gene level in bone tissue, which may be the mechanism of BBC on preventing and treating osteoporosis.

Animals↗
PubMed2005

[Chemical constituents in roots of Polygala fallax and their anti-oxidation activities in vitro].

OBJECTIVE: To study the chemical constituents in roots of P. fallax and their anti-oxidation activities in vitro. METHOD: Column chromatographic techniques were employed for isolation and purification of chemical constituents of the plant. The structures were elucidated on the basis of the spectral evidence and the physical and chemical character. The isolated compounds were screened with four anti-oxidation models in vitro. RESULT: Seven xanthones, 1,7-dihydroxy-2,3-methylenedioxyxanthone (1), 1-methoxy-2,3-methylenedioxyxanthone (2), 3-hydroxy-1,2-dimethoxyxanthone (3), 1,6,7-trihydroxy-2,3-dimethoxyxanthone (4), 7-hydroxy-1-methoxy-2,3-methylenedioxyxanthone (5), 1,3-dihydroxy-2-methoxyxanthone (6) and 1,3,7-trihydroxy-2-methoxyxanthone (7), were isolated from the roots of P. fallax. And compounds 1 - 7 showed different anti-oxidation activities in the different pharmacological models. CONCLUSION: Compounds 2, 3, 5 and 7 were isolated from this plant for the first time. Xanthones from this plant showed anti-oxidation activities. The pharmacological activities of the pure compounds from this plant were also reported for the first time.

Animals↗
PubMed2004

Cytotoxicity of three cycloartane triterpenoids from Cimicifuga dahurica.

We first investigated the cytotoxicity of three cycloartane triterpenoids isolated from the aerial part of C. dahurica. Their cytotoxic activity was investigated on several cancer cell lines including solid tumor (HepG2), blood tumor (HL-60), drug resistant tumor (R-HepG2) and primary cultured normal mouse and rat hepatocytes in order to find efficient anti-tumor agents against both parental and drug-resistant tumor with reduced toxicity. Evident cytotoxicity of these compounds on all tested neoplastic cell lines revealed that they are efficient on both drug-resistant tumor and parental tumor. Furthermore, they all showed relatively selective cytotoxicity on cancerous cells based on the higher IC(50) values of them on normal cells than that on tumor cells. Morphological observation and cell cycle analysis were employed to elucidate the cytotoxicity of the tested compounds. They brought out similar apoptotic morphological changes and G(2)/M cell cycle arrest in HepG2, R-HepG2 and HL-60 cells. Moreover, they suppressed the expression of cdc2 and COX-2 protein. These results imply that the three compounds possess potential anti-tumor activities and they exert their cytotoxicity via apoptosis and G(2)/M arrest. In addition, inhibition of cdc2 protein expression correlates with mechanism of G(2)/M arrest.

Animals↗
PubMed2004

Serum levels of matrix metalloproteinase 3 and macrophage colony-stimulating factor 1 correlate with disease activity in ankylosing spondylitis.

OBJECTIVE: To assess the usefulness of measuring serum matrix metalloproteinase 3 (MMP-3) and macrophage colony-stimulating factor (M-CSF) in patients with ankylosing spondylitis (AS). METHODS: Serum levels of MMP-3 and M-CSF were measured in AS patients who did and did not receive infliximab treatment. These were compared with those of 28 healthy subjects. RESULTS: In the group of AS patients not treated with biologics, both M-CSF and MMP-3 correlated with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) values, but not with each other. Logistic regression analysis showed that MMP-3 values were high in those with severely active disease. Infusions of infliximab in AS patients led to a significant decrease in the values of the BASDAI as well as the serum MMP-3, but no change in the serum M-CSF values. CONCLUSION: MMP-3 and M-CSF are potentially useful markers of AS disease activity.

Adolescent↗