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Yang Wang

Publications and source records attributed to Yang Wang.

At least 73 records · Page 4Linked to original sources
PubMed2006

Granulocyte colony-stimulating factor reduces cardiomyocyte apoptosis and improves cardiac function in adriamycin-induced cardiomyopathy in rats.

BACKGROUND: Cardiomyocyte apoptosis reportedly participates in the occurrence and progression of dilated cardiomyopathy (DCM). Recent studies have shown that granulocyte colony-stimulating factor (G-CSF) enhances bone marrow cells migration to the damaged heart in the DCM model and improves the ultrastructure of the cardiomyocyte in adriamycin (ADR) induced DCM. However, its influence on cardiac pump function and cardiomyocyte apoptosis has not been studied. METHODS AND MATERIALS: Wistar Rats were randomly grouped into control, ADR, ADR+PBS, ADR+G-CSF group (n = 10). ADR (2.5 mg/kg, 6 times for 2 weeks) was administered intraperitoneally in all rats except the control group. After 2 weeks, the rats in ADR+G-CSF group were injected with G-CSF (50 microg/kg/day for 8 days) subcutaneously. Cardiac function was evaluated by echocardiogram and cardiac catheterization after 4 weeks. Cardiomyocytes apoptosis and apoptosis-related protein Fas were detected by in situ terminal deoxynucleotidyl transferase assay (TUNEL method) and Western blot, respectively. RESULTS: The ADR and ADR+PBS groups showed significant deteriorations of left ventricular functions and high cardiomyocyte apoptosis index, as well as high Fas expressions. Meanwhile, the ADR+G-CSF group showed significant improvement in LV function, inhibition of cardiomyocyte apoptosis compared with the ADR and ADR+Phosphate-Buffered Saline PBS group. The Fas protein expression was remarkably attenuated as well. CONCLUSION: Our results suggest that administration of G-CSF inhibited cardiomyocyte apoptosis and Fas protein expression and contributes to improving cardiac pump function in vivo in ADR induced DCM rat model.

Animals↗
PubMed2006

Expression and significance of toll-like receptor 2,4 of peripheral blood mononuclear cells in acute abdomen patients associated with systemic inflammatory response syndrome.

The changes of Toll-like receptor (TLR) 2, 4 of peripheral blood mononuclear cells (PBMCs) in the acute abdomen patients associated with systemic inflammatory response syndrome (SIRS) and their potential significance were explored. A clinical study was performed on 103 acute abdomen patients in whom 65 were associated with SIRS. Forty healthy individuals served as normal controls. The mRNA expression of TLR2, 4 was detected by RT-PCR, and the expression of TNF-alpha and IL-6 by ELISA. The level of plasma endotoxin, hospital stay and mortality were measured. It was found that the endotoxin level was increased to varying degrees in all the acute abdomen patients, and the endotoxin level was and hospital stay longer in SIRS group than in non-SIRS group (P<0.01). TLR2 mRNA, TLR4 mRNA, IL-6 and TNF-alpha could be detected with low value in normal controls, but they were up-regulated markedly on the 1st day after admission. Then TLR4 mRNA, IL-6 and TNF-alpha were decreased gradually, but TLR2 mRNA maintained at a high level till the 5th day. These indexes above in SIRS group were higher than those in non-SIRS group (P<0.01). The results of correlation analysis revealed the expression of TLR2, 4 mRNA was positively correlated with the levels of TNF-alpha and IL-6, and the hospital stay. The results of Logistic regression demonstrated that overexpression of TLR2, 4 mRNA might result in higher risk of multiple organ dysfunction syndrome (MODS). It was concluded that in the acute abdomen patients associated with SIRS, the expression of TLR2, 4 in PBMCs was increased markedly, suggesting that TLR might play an important role in the pathogenesis of acute abdomen associated with SIRS.

Abdomen, Acute↗
PubMed2006

CD8(+) T cell-mediated immune responses in West Nile virus (Sarafend strain) encephalitis are independent of gamma interferon.

The flavivirus West Nile virus (WNV) can cause fatal encephalitis in humans and mice. It has recently been demonstrated, in an experimental model using WNV strain Sarafend and C57BL/6 mice, that both virus- and immune-mediated pathology is involved in WNV encephalitis, with CD8(+) T cells being the dominant subpopulation of lymphocyte infiltrates in the brain. Here, the role of activated WNV-immune CD8(+) T cells in mouse WNV encephalitis was investigated further. Passive transfer of WNV-immune CD8(+) T cells reduced mortality significantly and prolonged survival times of mice infected with WNV. Early infiltration of WNV-immune CD8(+) T cells into infected brains is shown, suggesting a beneficial contribution of these lymphocytes to recovery from encephalitis. This antiviral function was not markedly mediated by gamma interferon (IFN-gamma), as a deficiency in IFN-gamma did not affect mortality to two strains of WNV (Sarafend and Kunjin) or brain virus titres significantly. The cytolytic potential, as well as precursor frequency, of WNV-immune CD8(+) T cells were not altered by the absence of IFN-gamma. This was reflected in transfer experiments of WNV-immune CD8(+) T cells from IFN-gamma(-/-) mice into WNV-infected wild-type mice, which showed that IFN-gamma-deficient T cells were as effective as those from WNV-immune wild-type mice in ameliorating disease outcome. It is speculated here that one of the pleiotropic functions of IFN-gamma is mimicked by WNV-Sarafend-mediated upregulation of cell-surface expression of major histocompatibility complex antigens, which may explain the lack of phenotype of IFN-gamma(-/-) mice in response to WNV.

Adoptive Transfer↗
PubMed2006

Contextual modeling of functional MR images with conditional random fields.

This paper presents a conditional random field (CRF) approach to fuse contextual dependencies in functional magnetic resonance imaging (fMRI) data for the detection of brain activation. The interactions among both activation (activated/inactive) labels and observed data of brain voxels are unified in a probabilistic framework based on the CRF, where the interaction strength can be adaptively adjusted in terms of the data similarity of neighboring sites. Compared to earlier detection methods, including statistical parametric mapping and Markov random field, the proposed method avoids the suppression of high frequency information and relaxes the strong assumption of conditional independence of observed data. Experimental results show that the proposed approach effectively integrates contextual constraints within the detection process and robustly detects brain activities from fMRI data.

Algorithms↗
PubMed2006

A dynamic conditional random field model for foreground and shadow segmentation.

This paper proposes a dynamic conditional random field (DCRF) model for foreground object and moving shadow segmentation in indoor video scenes. Given an image sequence, temporal dependencies of consecutive segmentation fields and spatial dependencies within each segmentation field are unified by a dynamic probabilistic framework based on the conditional random field (CRF). An efficient approximate filtering algorithm is derived for the DCRF model to recursively estimate the segmentation field from the history of observed images. The foreground and shadow segmentation method integrates both intensity and gradient features. Moreover, models of background, shadow, and gradient information are updated adaptively for nonstationary background processes. Experimental results show that the proposed approach can accurately detect moving objects and their cast shadows even in monocular grayscale video sequences.

Algorithms↗
PubMed2006

Proteomic analysis of differential protein expression in early process of pancreatic regeneration in pancreatectomized rats.

AIM: A broad-range proteomic approach was applied to investigate the complexity of the mechanisms involved in pancreatic regeneration for identification of new targets of diabetes treatment and potential markers of pancreatic stem cells. METHODS: A regeneration pancreatic model was induced by 90% partial pancreatectomy (Px) in rats. Changes in the protein expression in regenerating rat pancreas on the third day after Px, as compared with rats that received sham surgery, were analyzed by using 2-D gel electrophoresis (2-DE), mass spectrometry (MS), and mass fingerprinting. RESULTS: 2-DE revealed 91 spots with at least 1.5-fold increases in expression at 3 d after pancreatectomy and 53 differentially expressed proteins that were identified by peptide mass fingerprinting (PMF). These included cell growth-related, lipid and energy metabolism-related, protein and amino acid metabolism-related proteins, and signal transduction proteins. Vimentin, CK8, L-plastin, hnRNP A2/B1, and AGAT are associated with embryogenesis and cell differentiation, and may be new potential pancreatic stem cells markers. CONCLUSION: The proteome profiling technique provided a broad-based and effective approach for the rapid assimilation and identification of adaptive protein changes during pancreas regeneration induced by pancreatectomy. Our data clarify the global proteome during the pancreatic proliferation and differentiation processes, which is important for better understanding of pancreatic regeneration and for discovering of protein biomarkers for pancreatic stem cells.

Amidinotransferases↗
PubMed2006

Syntheses, molecular targets and antitumor activities of novel triptycene bisquinones and 1,4-anthracenedione analogs.

Novel substituted triptycene bisquinones and 1, 4-anthracenediones were synthesized and screened for their anti-cancer activities. A number of analogs were synthesized utilizing various synthetic transformations and found to elicit interesting antitumor effects. Analogs included water-soluble pro-drugs and ammonium salts. These potent antitumor drugs are DNA topoisomerase inhibitors that induce DNA strand breaks, inhibit DNA, RNA and protein syntheses and reduce tumor cell proliferation in the nanomolar range in vitro. They induce cytochrome c release, caspase-9, -3 and -8 activities, poly(ADP)-ribose polymerase-1 (PARP) cleavage, and internucleosomal DNA fragmentation by a mechanism which involves caspase-2 activation but not Fas signaling. Moreover, these drugs remain effective in multidrug-resistant tumor cells and have the advantage of blocking nucleoside transport and inducing a rapid loss of mitochondrial transmembrane potential. Based on their effects in tumor cells and isolated mitochondria, it is hypothesized that these drugs might, directly and indirectly, target components of the permeability transition pore to induce mitochondrial permeability transition and the release of proapoptotic factors. This review provides a summary of synthetic efforts and mechanistic endeavor.

Animals↗
PubMed2006

New generation of liposomal drugs for cancer.

This review is focused on liposomes as a delivery system for anticancer agents and more specifically on the advantages of using liposomes as drug nanocarrier in cancer chemotherapy. The main advantages of liposomal drugs over the non-encapsulated drugs include: (1) improved pharmacokinetics and drug release, (2) enhanced intracellular penetration, (3) tumor targeting and preventing adverse side effects and (4) ability to include several active ingredients in one complex liposomal drug delivery system (DDS). The review also includes our recent data on advanced liposomal anticancer drug delivery systems. As a conclusion we propose a novel liposomal DDS which includes inhibitors of pump resistance combined in one liposomal drug delivery system with an inhibitor of antiapoptotic cellular defense, an apoptosis inducer (a traditional anticancer drug) and a targeting moiety. The proposed drug delivery system utilizes a novel three tier approach, simultaneously targeting three molecular targets: (1) extracellular receptors or antigen expressed on the surface of plasma membrane of cancer cells in order to direct the whole system specifically to the tumor, preventing adverse side effects on healthy tissues; (2) drug efflux pumps in order to inhibit them and enhance drug retention by cancer cells, increasing intracellular drug accumulation and thereby limiting the need for prescribed high drug doses that cause adverse drug side effects; and (3) intracellular controlling mechanisms of apoptosis in order to suppress cellular antiapoptotic defense.

Animals↗
PubMed2006

[Primary study on proteomics about Ganoderma lucidium spores promoting survival and axon regeneration of injured spinal motor neurons in rats].

OBJECTIVE: To detect some proteins associated with the effect of ganoderma lucidium spores (GASP) on promoting the survival and axon regeneration of injured spinal motor neurons in rats. METHODS: The rats were divided into normal control group, untreated group and GASP-treated group, and the rats in the last two groups received ventral root avulsion. GASP preparation was fed to the rats in the GASP-treated group for 14 days. The gray matter tissues of the lumbar spinal were sampled from rats in each group after 14 days following ventral root avulsion, and the extracted proteins from these tissues were detected by using 2-dimensional electrophoresis. Matrix assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS) was utilized to identify the differentially expressed proteins among these three groups. RESULTS: There were six kinds of proteins differentially expressed among the three groups, which were collapsin response mediator protein 2 (CRMP-2), F-actin capping protein beta subunit (FCP-beta), isocitrate dehydrogenase [NAD] subunit beta (IDH-beta), ATPase, glutamate oxaloacetate transaminase-1 (GOT1) and M2 pyruvate kinase (M2-PK). The expression levels of CRMP-2, IDH-beta, ATPase and GOT1 were higher in the GASP-treated group than those in the untreated group, while the expression levels of FCP-beta and M2-PK were lower than those in the untreated group. CONCLUSION: GASP maybe promotes the survival and axon regeneration of injured spinal motor neurons in rats by virtue of up- or down-regulating the expression levels of the proteins mentioned above.

Actin Capping Proteins↗
PubMed2006

Bilateral comparison of conventional versus topographic-guided customized ablation for myopic LASIK with the NIDEK EC-5000.

PURPOSE: To compare visual acuity and higher order aberrations before and after myopic LASIK using conventional versus customized ablation. METHODS: This prospective, randomized study included 54 myopic eyes in 27 patients who underwent bilateral LASIK using the NIDEK EC-5000 excimer laser system (NIDEK Technologies, Gamagori, Japan). Customized aspheric treatment zone (CATz) treatment was used in one eye (CATz group) and conventional ablation (conventional group) was used in the fellow eye. Uncorrected visual acuity (UCVA) and higher order aberrations (root-mean-square [RMS] in 4-mm and 6-mm zones) of both groups were observed with the NIDEK OPD-Scan aberrometer before and 3 months after LASIK. Preoperative mean refractive error was similar for both eyes of each patient (P>.05). RESULTS: No statistically significant differences were noted in preoperative higher order aberrations (RMS in 4-mm and 6-mm zones) between groups (P>.05). No statistically significant difference was noted between pre- and postoperative higher order aberrations in the CATz group (P>.05). However, a highly statistically significant increase in higher order aberrations was observed after conventional ablation (P<.001). There was a statistically significant higher increase of higher order aberrations after LASIK in the conventional group than the CATz group (P<.05). Postoperative UCVA with both conventional and customized ablation was not significantly different (P>.05). CONCLUSIONS: LASIK with conventional ablation and CATz ablation resulted in the same UCVA. The increase in higher order aberrations after CATz ablation was less than after conventional ablation.

Adolescent↗
PubMed2006

Antitumor triptycene analogs induce a rapid collapse of mitochondrial transmembrane potential in HL-60 cells and isolated mitochondria.

Since synthetic analogs of triptycene (TT code number), such as bisquinones TT2 and TT13, can trigger cytochrome c release without caspase activation and retain their ability to induce apoptosis in multidrug-resistant (MDR) tumor cells, fluorescent probes of transmembrane potential have been used to determine whether these antitumor compounds might directly target mitochondria in cell and cell-free systems to cause the collapse of mitochondrial membrane potential ( downward arrow Deltapsim) that is linked to permeability transition pore (PTP) opening. Using JC-1 dye, the abilities of various TT analogs to induce the downward arrow Deltapsim in wild-type and MDR HL-60 cells are rapid (within 5-20 min), irreversible after drug removal, concentration dependent in the 0.64-25 microM range, and generally related to their antitumor activities in vitro. The downward arrow Deltapsim caused by TT2 and TT13, which are more potent than mitoxantrone, staurosporine and the reference depolarizing agent, carbonyl cyanide m-chlorophenylhydrazone (CCCP), in HL-60 cells, are not prevented by caspase-2 or -8 inhibitors, suggesting that activation of these apical caspases upstream of mitochondria is not involved in this process. Antitumor TT analogs (0.64-25 microM) also mimic the abilities of the known depolarizing agents, CCCP, alamethicin, gramicidin A and 100 microM CaCl(2), to directly induce within 20 min the downward arrow Deltapsim in isolated mitochondria prepared from mouse liver and loaded with rhodamine 123 dye. The fact that 20 microM Ca(2+), which is insufficient to trigger depolarization on its own, is required to reveal the depolarizing effect of TT2 in isolated mitochondria suggests that antitumor TT analogs might interact with the PTP to alter its conformation and increase its Ca(2+) sensitivity. Indeed, such Ca(2+)-dependent downward arrowDeltapsim of isolated mitochondria treated with 25 microM TT2 or 100 microM Ca(2+) are blocked by ruthenium red. Daunorubicin (DAU) is unable to mimic the rapid downward arrowDeltapsim caused by antitumor TT bisquinones within 5-40 min of treatment in HL-60 cells or isolated mitochondria. Moreover, the downward arrowDeltapsim caused by 25 microM TT2 or 100 microM Ca(2+) in isolated mitochondria are similarly blocked by cyclosporin A (CsA), bongkrekic acid and decylubiquinone, which prevent PTP opening, suggesting that, in contrast to DAU, antitumor TT analogs that directly target mitochondria to trigger the Ca(2+)-dependent and CsA-sensitive downward arrowDeltapsim, might induce PTP opening and the mitochondrial pathway of apoptosis even in the absence of nuclear signals.

Antineoplastic Agents↗
PubMed2006

The expression of toll-like receptor 2, 4 of livers in mice with systemic inflammatory response syndrome.

BACKGROUND: The complicated pathogenesis of systemic inflammatory response syndrome (SIRS) is a hot topic in critical care medicine. In this study we explored the expression of toll-like receptor (TLR) 2, 4 of livers in SIRS mice and evaluated the role of TLR2, 4 in the pathogenesis of SIRS. METHODS: Forty BABL/C mice were randomly divided into 2 groups: control (n=20) and SIRS (n=20). SIRS model was induced by severe acute pancreatitis. Blood routine, blood amylase, glutamic pyruvic transaminase and temperature were measured. Histological changes of pancreases and livers were observed microscopically. The mRNA expressions of TLR2, 4 were detected by real-time polymerase chain reaction (PCR). The protein expressions of TLR2, 4 were examined by Western blot. RESULTS: Marked edema, inflammatory cell infiltration, hemorrhage, and necrosis were observed in the pancreases and livers of SIRS mice. The concentrations of amylase and glutamic pyruvic transaminase were increased significantly. Body temperature and white blood cell count were decreased. The mRNA and protein expressions of TLR2, 4 increased markedly in SIRS mice. Significant difference was observed between SIRS and control mice (P<0.01). CONCLUSION: The expressions of TLR2, 4 of livers were increased markedly in SIRS mice, indicating that TLR might play an important role in the pathogenesis of SIRS.

Animals↗
PubMed2006

[Prognostic value of N-terminal-pro-brain natriuretic peptide on admission in patients with chronic heart failure].

OBJECTIVE: Heart failure is responsible for a huge burden in hospital care. Our goal was to evaluate the value of N-terminal-pro-brain natriuretic peptide (Nt-proBNP) on predicting death or hospital readmission after hospital discharge in patients with chronic heart failure (CHF). METHODS: From March 2003 to April 2005, 135 consecutive patients (97 male and 38 female, mean age 60.7 years +/- 13.1 years) with chronic heart failure [dilated cardiomyopathy (44%) and coronary heart disease (35%)] were included in this study. Plasma concentrations of the Nt-proBNP were measured by ELISA on admission. All patients received conventional therapy and were followed up for 24 months. The primary end point was death or readmission. RESULTS: (1) During the follow up period (640 days +/- 100 days), 11 patients died and 39 patients rehospitalized, the median Nt-proBNP level on admission was significantly higher in patients died during the follow up period (5908 ng/L) than that of rehospitalized patients (2768 ng/L, P = 0.038). Plasma Nt-proBNP level on admission were significantly higher in primary end point group (n = 50, 2947 ng/L) than that in non-primary end point group (n = 85, 917 ng/L, P < 0.01). (2) Variables associated with an increased hazard of death and/or rehospitalization were Nt-proBNP and NYHA degree when analyzed by logistic regression models. Increased Log Nt-proBNP was the strongest independent predictor of an adverse outcome of CHF (odds ratio 13.8, 95% confidence interval 2.29 to 2.78, P < 0.01). (3) Area under the curve for Nt-proBNP in evaluating prognosis of CHF patients was 0.885 (positive predictive value 88.5%, negative predictive value 11.5%). CONCLUSION: Nt-proBNP level on admission is a strong predictor of rehospitalization and death within 24 months after hospital discharge in patients with chronic heart failure.

Adolescent↗
PubMed2006

[Analysis of influence factors and control methods on iron release phenomenon in drinking water distribution system].

Variation rule of iron in drinking water distribution systems was studied, and it was found that the iron released from the scale to the bulk water was the primary reason for iron overstep. The main chemical composition of the scale in cast iron pipe and galvanized steel pipe was iron in a northern city in China. In the drinking water distribution systems, when the value of dissolved oxygen or chlorine residual was low, the iron release phenomenon was severe. The reason for that was the passivation layer of the corrosion scale was destroyed in reductive condition and the result was a great amount of iron in ferrous form was released. According to the research results, the control methods for iron release and 'red water' phenomenon were indicated.

China↗
PubMed2006

[The research of the adsorption and desorption behaveior of macroporous resin for glycyrrhizic acid].

OBJECTIVE: To investigate the performance of static and dynamic adsorption and desorption of the three macroporous resins of AB-8, D-101 and H-103. METHOD: Compare the adsorption and desorption of the three macroporous resins for glycyrrhizic acid by determining the static adsorption, static desorption, dynamic adsorption and dynamic desorption through detecting the glycyrrhizic acid content by HPLC method. RESULT: The saturation of AB-8 is 0.75 g (crude drug)/mL (macroporous resins), the best elution reagent is 50% EtoH and it's eluation ration is 68.81% . The saturation of D-101 is 0.75 g (crude drug)/mL (macroporous resins), the best elution reagent is 60%EtoH and it's eluation ration is 64.67%. The saturation of H-103 is 0.5 g (crude drug)/mL (macroporous resins), the best elution reagent is 50%E-toH and it's elution ration is 51.18%. CONCLUSION: AB-8 and D-101 are the superior absorbents for glycyrrhizic acid.

Adsorption↗
PubMed2006

[Analysis of the characteristics of corrosion scale in drinking water distribution systems].

Scanning electron microscopy, X-ray fluorescence spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy were used to analyze the microstructure, chemical composition, crystalline structure and compound constitute of the corrosion scale from cast iron pipe and galvanized steel pipe in drinking water distribution systems. The outer of the corrosion scale was compact, while the inner was porous. Iron was the primary chemical element of the corrosion scale, and the composition of the scale was iron compounds. The outer scale were ferric compounds such as alpha-FeOOH, gamma-FeOOH, alpha-Fe2O3, gamma-Fe2O3, FeCl3, while the inner were ferrous compounds such as Fe3O4, FeCl2, FeCO3. The characteristics of the corrosion scale was lying on hydraulic conditions and water quality in distribution systems, and the characteristics of iron pipe materials.

Corrosion↗
PubMed2006

[Transrectal ultrasound-guided ethanol sclerotherapy for Müllerian duct cyst accompanied with ejaculatory duct obstruction].

OBJECTIVE: To evaluate the efficacy and safety of transrectal ultrasound-guided ethanol sclerotherapy in the treatment of Müllerian duct cyst accompanied with ejaculatory duct obstruction. METHODS: Under the transrectal ultrasound guidance, 3 cases of prostate Müllerian duct cyst were treated by 20 G needle puncture and ethanol injection, and closely followed up by ultrasonic monitored on follow-up examinations. RESULTS: All the cysts involuted completely 6 months after the treatment. Symptoms caused by ejaculatory duct obstruction were relieved in all the patients. No severe complications occurred. CONCLUSION: Transrectal ultrasound-guided ethanol sclerotherapy is an effective and safe method for the treatment of Müllerian duct cyst accompanied with ejaculatory duct obstruction.

Adult↗