Biomedical subjects

Xiong Wang

Publications and source records attributed to Xiong Wang.

16 recordsLinked to original sources

PubMed2026

CancerOmicsStudio (CoS): a web server for integrative and interpretable analysis of multi-omics cancer data.

MOTIVATION: Large-scale omics resources, including The Cancer Genome Atlas, Genomics of Drug Sensitivity in Cancer, and the Cancer Dependency Map, have become essential for cancer research. However, these datasets are distributed across different platforms, formats and analysis frameworks, which limits their practical use by researchers without extensive computational expertise. RESULTS: We developed CancerOmicsStudio (CoS), a web server for integrative and interpretable analysis of multi-omics cancer data across 33 cancer types. CoS provides five major modules: CosAI, Traditional Analysis, Drug Sensitivity, CRISPR Dependency and Single-Cell Tumor Microenvironment. The Traditional Analysis module supports expression comparison, diagnostic evaluation, survival analysis, enrichment analysis and gene correlation. The Drug Sensitivity and CRISPR Dependency modules enable systematic evaluation of gene-drug response associations and gene essentiality in cancer cell lines. The Single-Cell Tumor Microenvironment module supports tumor microenvironment analysis at single-cell resolution. In total, approximately 1.23 million results have been precomputed to enable rapid retrieval. CosAI further allows users to submit natural-language queries and obtain results through a Real-time Analysis as Retrieval framework, with responses summarized by a lightweight language model. AVAILABILITY AND IMPLEMENTATION: CancerOmicsStudio is freely available at Zenodo (doi: 10.5281/zenodo.18744990) and https://cos.wanglab.bio.

Humans↗

PubMed2006

Assembled CuO hollow spheres from nanoparticles.

CuO microspheres with hollow interiors were synthesized by a simple method using urea as an important reagent to generate soft-template. X-ray diffraction pattern, Infrared spectrum, electronic diffraction, field emission scanning electron microscopy images, transmission electron microscopy images and high-resolution transmission electron microscopy investigated the phase structures and morphologies of CuO microspheres. The hollow spheres may be formed through the assembling of nanoparticles with the assistance of gas bubbles and a self-generated template and aggregation process was proposed for the formation mechanism of the CuO spheres.

Copper↗

PubMed2006

Formation of uniform single-crystalline bismuth sulfide nanowires under mixed-solvent condition.

Uniform single-crystalline bismuth sulfide nanowires were prepared via a convenient solvothermal route under mixed-solvent condition. The nanowires were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX) spectrometry and UV-vis spectrophotometer. The growth mechanism of the one-dimensional nanostructures was discussed. The optical absorption band gap of the nanowires is about 1.7 eV, and the blue-shift phenomenon can be observed with respect of that of the bulk Bi2S3, which might bring in new types of applications.

Bismuth↗

PubMed2006

[Action of AMP579 and adenosine on potassium or sodium ionic channels in isolated rat and guinea pig ventricular myocytes].

AIM: To study the effect of AMP579 and adenosine on potassium ionic (K+) or sodium ionic (Na+) channels and to elucidate ionic mechanisms underlying negative inotropic and antiarrhythmic effects of AMP579 and adenosine. METHODS: Ionic channel currents of rat and guinea pig ventricular myocytes were recorded by patch clamp technique in whole-cell configuration. RESULTS: Adenosine showed a stronger activating effect on transient outward K+ current (I(to)) than AMP579, EC50 of adenosine and AMP579 were 2.33 and 8. 32 micromol x L(-1), respectively (P < 0.05). An adenosine A1 receptor blocker, 1,3-dipropyl-8-cyclopentylxanthine (PD116948), can abolish the effects of AMP579 and adenosine on I(to), demonstrating that the effect is mediated by adenosine A1 receptor. Adenosine exerted a more obvious inhibitory effect on delayed rectifier K+ current (IK) than AMP579. IC50 of adenosine and AMP579 were 1.21 and 2.31 micromol x L(-1), respectively (P < 0.05). AMP579 had a more powerful inhibitory effect on inward rectifier K+ current (IK1) than adenosine. IC50 of AMP579 and adenosine were 4.15 and 20.7 micromol x L(-1), repectively (P < 0.01). AMP579 and adenosine exerted a similar inhibitory effect on fast inward Na+ current (INA), IC50 of AMP579 and adenosine were 9.46 and 6.23 micromol x L(-1), respectively (P > 0.05). CONCLUSION: Adenosine showed a stronger activating effect on I(to) than AMP579, however, the mechanism of AMP579 and adenosine activating I(to) was mediated by adenosine A1 receptor. AMP579 has a more powerful inhibitory effect on IK1, and less inhibitory effect on IK than adenosine. Both drugs have a similar inhibitory effect on INa. The negative inotropic and antiarrhythmic effects are related to these ionic mechanisms.

Adenosine↗

PubMed2005

Single-source approach to cubic FeS2 crystallites and their optical and electrochemical properties.

Cubic FeS2 crystallites have been synthesized via a single-source approach using iron diethyldithiocarbamate as precursor under hydrothermal conditions. The sample is characterized by XRD, IR, TEM, and FESEM. The optical properties of the as-prepared FeS2 reveal that there exists a red shift compared with that of bulk materials. Meanwhile, the electrochemical properties of FeS2 demonstrate that it delivers a large discharge capacity, which might find possible application as an electrode material in lithium cells. It is also found that the reaction temperature is of importance to the formation of cubic FeS2 crystallites.

Journal Article↗

PubMed2005

MetricMap: an embedding technique for processing distance-based queries in metric spaces.

In this paper, we present an embedding technique, called MetricMap, which is capable of estimating distances in a pseudometric space. Given a database of objects and a distance function for the objects, which is a pseudometric, we map the objects to vectors in a pseudo-Euclidean space with a reasonably low dimension while preserving the distance between two objects approximately. Such an embedding technique can be used as an approximate oracle to process a broad class of distance-based queries. It is also adaptable to data mining applications such as data clustering and classification. We present the theory underlying MetricMap and conduct experiments to compare MetricMap with other methods including MVP-tree and M-tree in processing the distance-based queries. Experimental results on both protein and RNA data show the good performance and the superiority of MetricMap over the other methods.

Algorithms↗

PubMed2005

Effects of AMP579 and adenosine on L-type Ca2+ current in isolated rat ventricular myocytes.

AIM: To compare the effects of AMP579 and adenosine on L-type Ca2+ current (I(Ca-L)) in rat ventricular myocytes and explore the mechanism by which AMP579 acts on I(Ca-L). METHODS: I(Ca-L) was recorded by patch-clamp technique in whole-cell configuration. RESULTS: Adenosine (10 nmol/L to 50 micromol/L) showed no effect on basal I(Ca-L), but it inhibited the I(Ca-L) induced by isoproterenol 10 nmol/L in a concentration-dependent manner with the IC(50) of 13.06 micromol/L. Similar to adenosine, AMP579 also showed an inhibitory effect on the I(Ca-L) induced by isoproterenol. AMP579 and adenosine (both in 10 micromol/L) suppressed isoproterenol-induced ICa-L by 11.1% and 5.2%, respectively. In addition, AMP579 had a direct inhibitory effect on basal I(Ca-L) in a concentration-dependent manner with IC50 (1.17 micromol/L). PD116948 (30 micromol/L), an adenosine A1 receptor blocker, showed no action on the inhibitory effect of AMP579 on basal I(Ca-L). However, GF109203X (0.4 micromol/L), a special protein kinase C (PKC) blocker, could abolish the inhibitory effect of AMP579 on basal I(Ca-L). So the inhibitory effect of AMP579 on basal I(Ca-L) was induced through activating PKC, but not linked to adenosine A1 receptor. CONCLUSION: AMP579 shows a stronger inhibitory effect than adenosine on the I(Ca-L) induced by isoproterenol. AMP579 also has a strong inhibitory effect on basal I(Ca-L) in rat ventricular myocytes. Activation of PKC is involved in the inhibitory effect of AMP579 on basal I(Ca-L) at downstream-mechanism.

Adenosine↗

PubMed2004

Deformation mechanism of leukocyte adhering to vascular surface under steady shear flow.

The adhesion of leukocytes to vascular surface is an important biomedical problem and has drawn extensive attention. In this study, we propose a compound drop model to simulate a leukocyte with a nucleus adhering to the surface of blood vessel under steady shear flow. A two-dimensional computational fluid dynamics (CFD) is conducted to determine the local distribution of pressure on the surface of the adherent model cell. By introducing the parameter of deformation index (DI), we investigate the deformation of the leukocyte and its nucleus under controlled conditions. Our numerical results show that: (i) the leukocyte is capable of deformation under external exposed flow field. The deformation index increases with initial contact angle and Reynolds number of external exposed flow. (ii) The nucleus deforms with the cell, and the deformation index of the leukocyte is greater than that of the nucleus. The leukocyte is more deformable while the nucleus is more capable of resisting external shear flow. (iii) The leukocyte and the nucleus are not able to deform infinitely with the increase of Reynolds number because the deformation index reaches a maximum. (iv) Pressure distribution confirms that there exists a region downstream of the cell, which produces high pressure to retard continuous deformation and provide a positive lift force on the cell. Meanwhile, we have measured the deformation of human leukocytes exposed to shear flow by using a flow chamber system. We found that the numerical results are well consistent with those of experiment. We conclude that the nucleus with high viscosity plays a particular role in leukocyte deformation.

Cell Adhesion↗

PubMed2004

Effects of steady shear flow on the deformation of leukocyte adhered to vascular endothelial surface.

OBJECTIVE: To investigate the effects of steady shear flow on the deformation properties of an adherent leukocyte and its nucleus. METHOD: A compound drop model was developed to simulate the leukocyte adhered to the inner surface of a blood vessel, and a two dimensional computational fluid dynamics (CFD) was conducted to solve the model equations. RESULT: The results show: 1) The Reynolds number of the external shear flow plays a crucial role in leukocyte deformation. Leukocyte deformation increases with Reynolds number; 2) The nucleus deforms together with the leukocyte, and the deformation index of the leukocyte is greater than that of the nucleus. The leukocyte is more deformable while the nucleus is more capable of resisting external shear flow; 3) The leukocyte and the nucleus will not deform infinitely when the Reynolds number increases beyond a certain value where the deformation index reaches its maximum; 4) Pressure distribution over the surface demonstrated that there exists a region downstream of the cell, where is high pressure produced to retard continuous deformation and to provide a positive lift force on the cell. CONCLUSION: The nucleus with high viscosity plays a particular role in leukocyte deformation under shear flow.

Biomechanical Phenomena↗

PubMed2004

[The research progress in ligament tissue engineering].

Ligament injury always has an unsatisfied outcome because of the poor blood supply and scar tissue formation. This may result in severe joint dysfunction. Tissue engineering, as a most prospective field, may provide an effective approach for the treatment of ligament injury. This paper has reviewed some recently published articles focusing on the sources of seed cells in ligament tissue engineering, application of growth factors, screening of scaffold materials with specific mechanical and biodegradable properties, and interaction between cells and scaffold materials. At present, what should be extensively studied are scaffolds with specific mechanical and biodegradable properties, and bioreactors providing three-dimensional culture microenvironment mimic in vivo.

Animals↗

PubMed2003

Comparative studies of LFA-1/ICAM-1 interaction by micropipette and flow chamber techniques.

Interaction of lymphocyte function-associated antigen-1 (LFA-1) with intercellular adhesive molecule-1 (ICAM-1) is important in a number of cellular events, including inflammation, adhesion, transendothelial migration. The aim of this work was to study comparatively the adhesive interaction between LFA-1 and ICAM-1 by a micropipette technique and a flow chamber method, and also to explore the effects of tumor necrosis factor (TNF-alpha), phytohemagglutinin (PHA), and tetramethylpyrazine (TMP) on this interaction. The adhesion probability (Pa) between a lymphocyte cell line SKW-3 expressing LFA-1 and a red blood cell (RBC) coated with soluble ICAM-1 was approached by the micropipette technique, while the flow chamber allowed to observe the firm adhesion of SKW-3 on human umbilical vein endothelial cells (HUVECs). Experimental results show that PHA stimulation of lymphocytes resulted in significant increases in the adhesion probability (Pa) and in number of firmly adhered lymphocytes to HUVECs, but TMP treatment could significantly inhibit such increases.

Adult↗

PubMed2003

Changes of vasodilator-stimulated phosphoprotein (VASP) and its phosphorylation in endothelial cells exposed to laminar flow.

Vasodilator-stimulated phosphoprotein (VASP), an actin filaments-associated protein expressed mainly in focal adhesions and dynamic membrane regions of endothelial cells (ECs), serves as a substrate for cAMP and cGMP-dependent protein kinases. In this work, we studied the effect of laminar shear stress in vitro on the location and expression of the VASP as well as its phosphorylation associated with actin reorganisation in human umbilical endothelial cells (HUVECs). The distributions of VASP and microfilaments were observed by a fluorescent double staining. The level of VASP expression in cells was quantified by western blot. Experiments showed that, after exposure to a shear stress of 10 dyn/cm(2) for 24 h, besides the elongation and orientation of the cells, and spots of VASP were found along thick stress fibres, particularly at their two extremities. Western blot data showed conversions up to 11.4% and 8.9% of the 46 kD non-phosphorylated form VASP to its 50 kD phosphorylated form after exposures of 1 h and 4 h respectively to the same shear stress. The shear stress of 15 dyn/cm(2) had qualitatively the same effect as that of 10 dyn/cm(2), but with a lower magnitude. However, the shear stress of 2 dyn/cm(2) had much slower and weaker effects on the same tendency. These results suggest that a laminar shear stress can induce VASP translocation and phosphorylation that proceed actin filaments rearrangement along with the flow direction in HUVECs.

Actins↗

PubMed2003

[A biomechanical model for simulating the deformation of a leukocyte adhered to the surface of a blood vessel under steady shear flow].

The adhesion of leukocytes to substrate is an important biomedical engineering problem and has drawn extensive research. In this study, we have proposed a compound drop model to simulate a leukocyte with a nucleus adhered to the surface of a blood vessel under steady shear flow. A two-dimensional computational fluid dynamics (CFD) is conducted to determine the local distribution of pressure on the surface of the adherent model cell. By introducing the parameter of deformation index (DI), we have investigated the deformation of the model cell and it's nucleus under controlled conditions. Our numerical results show that: (1) the model cell is capable of deformation with the increase of initial contact angle, capillary number, and Reynolds number, and that the cytoplasm is more deformable while the nucleus is more capable of resisting external imposed shear flow; (2) the model cell is not able to deform infinitely with the increase of external shear flow because the deformation index reaches a maximum; (3) pressure distribution confirms that there exists a region downstream of the cell, which produces high pressure to retard continuous deformation and provide a positive lift force on the cell. Our results of nucleus deformation may help to develop a better understanding of how leukocytes transduce external mechanical signal like shear stress into nucleus.

Biomechanical Phenomena↗

PubMed2003

[Changes in the VASP expression feature of endothelial cells under steady laminar flow].

To investigate the effects of physiological shear stress on the vasodilator-stimulated phosphoprotein (VASP) location and expression changes associated with actin remodeling, we isolated and cultured human umbilical endothelial cells(HUVECs) with trypsin digestion. A parallel-plated flow chamber device was used to create laminar shear stress in vitro. The distributions of VASP and microfilaments in cells were observed by double staining with Alexa488 and rhodamine-phalloidin. Changes of VASP expression and phosphorylation were analyzed quantitatively with Western blot before and after exposure to shear flow for different times. We found that, under a shear stress of 10 dyn/cm2, HUVECs were elongated and oriented gradually to the flow direction. Microfilaments were recruited and oriented also to the flow direction with thicker VASP, specially targeted to their extremities. Western blotting data showed a rapid phosphorylation of VASP, and an increase of total VASP expression which peaked at 2 h (2 folds), then recovered until 8 h, followed by a slow increase again. These results suggest that VASP is a potential component which participates in the regulation of cell actin remodelling induced by shear flow.

Cell Adhesion Molecules↗

PubMed2002

Studies on single-cell adhesion probability between lymphocytes and endothelial cells with micropipette technique.

An in vitro model with micropipette technique was used to investigate single-cell adhesion probability between lymphocytes and endothelial cells. The basal adhesion probability between lymphocytes and endothelial cells was low and was significantly increased when either lymphocytes were activated by phytohemagglutinin (PHA) or endothelial cells were stimulated by tumor necrosis factor. The adhesion probability of lymphocytes to human umbilical vein endothelial cells was similar to that of lymphocytes to human brain microvascular endothelial cells (HB-MVEC). However, lymphocyte adhesion probability was higher in HB-MVEC than in mouse brain microvascular endothelial cells (MB-MVEC) under both resting and activated conditions. Furthermore, lymphocytes preincubated with monoclonal antibodies to lymphocyte function-associated antigen-1 (LFA-1) or HB-MVEC preincubated with monoclonal antibodies to intercellular adhesion molecule 1 (ICAM-1) significantly down-regulated the adhesion probability between lymphocytes and endothelial cells, indicating that the adhesion probability is related to the expression of LFA-1 on lymphocytes and to the expression of ICAM-1 on endothelial cells. Lymphocytes isolated from patients with cerebral stroke exhibited increased adhesion probability to HB-MVEC as compared with lymphocytes from healthy donors. Preincubation of lymphocytes with tetramethylpyrazine (TMP), an extract from a Chinese traditional herb, effectively inhibited the adhesion probability to HB-MVEC, suggesting that TMP has a potential therapeutic value. These results indicate that the micropipette technique is a useful model for investigating single-cell adhesion probability between lymphocytes and endothelial cells in vitro.

Animals↗

PubMed2002

[Simulation of the deformation of the endothelial cell under a shear flow].

The coupling between the endothelium and blood flow is an important biomedical problem and has drawn extensive research. Endothelial cells are known to adapt their shapes and functions in response to applied shear flow. Shear Stress being regarded as a primary triggering signal for cellular remodeling, it is important to understand the interaction mechanism between applied shear flow and endothelial cells. In present study we have established a theoretical model to simulate the coupling between the deformation of an endothelial cell and applied shear flow. A two dimensional computational fluid dynamic (CFD) is conducted to determine the local distributions of mechanical stress and pressure on cell surface. Our results show that: (1) the deformation of endothelial cell changes with alpha (corresponding to the shear stress imposed on cell surface by flow fluid). When alpha is greater than 0.021, the cell deformability increases greatly; (2) the distributions of stress and pressure on cell surface are not uniform, but the maximal shear stress and displacement are always at the top point of the cell. Meanwhile, we have measured the deformation of cultured human aortic endothelial cells (HAECs) exposed to shear flow by using a flow chamber. We found that the numerical results are well consistent with those of experiment. These results suggest that the non-uniformity distributions of mechanical stress and pressure on cell surface may play a particular role in the mechanism of cell activation and in the regulation of endothelial cells functions (modification of cytoskeleton, distributions of adhesion molecules, etc.). The present study offers a framework to facilitate the development of a comprehensive dynamic model for endothelial cells.

Aorta↗