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Kang Li

Publications and source records attributed to Kang Li.

16 recordsLinked to original sources
PubMed2026

SLC25A45 as a prognostic biomarker promotes malignant progression via mutant p53 in hepatocellular carcinoma.

BACKGROUND: SLC25A45 belongs to the mitochondrial trimethyllysine carrier protein family. To date, its role in tumor development has not been fully elucidated. Previous studies have demonstrated its pro-tumor function in ovarian cancer; however, research on the expression characteristics, biological roles and underlying regulatory pathways of SLC25A45 in hepatocellular carcinoma (HCC) is limited. This study aims to explore the expression, functional roles, and regulatory pathways of SLC25A45 in HCC. METHODS: This study examined SLC25A45 expression and clinical relevance in HCC using publicly available transcriptomic data. SLC25A45 knockdown cell lines were constructed using PLC/PRF/5, Huh7, and Huh1 cells. Functional assays, including cell proliferation and colony formation assays, were then conducted. To investigate the effects of SLC25A45 knockdown on the malignant phenotypes of HCC cells in vitro, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene set enrichment analysis (GSEA) analyses were performed to identify potential underlying mechanisms, which were subsequently validated by experimental assays. RESULTS: SLC25A45 was elevated in clinical HCC specimens, and high SLC25A45 expression was correlated with disease progression and poor overall survival (OS). In vitro functional assays demonstrated that SLC25A45 silencing reduced HCC cell proliferation and colony formation. Mechanistically, GSEA indicated that high SLC25A45 expression was significantly enriched in the p53 signaling pathways. SLC25A45 knockdown in HCC cells led to a significant increase in wild-type p53 protein expression, but a substantial decrease in mutant p53 expression. CONCLUSIONS: SLC25A45 is a potential prognostic indicator and may drive HCC tumorigenesis and progression through the differential modulation of the p53 signaling pathways.

SLC25A45↗
PubMed2026

Quercetin, a flavonoid, suppresses viral proliferation by interfering with the ubiquitin transfer from E1 to E2 enzymes.

Quercetin is recognized for diverse pharmacological activities. However, the mechanism underlying its broad-antiviral effects has not been elucidated. Herein, we identified quercetin as a potent inhibitor of both double-stranded DNA virus Bombyx mori nucleopolyhedrovirus (BmNPV) and single-stranded RNA virus porcine reproductive and respiratory syndrome virus (PRRSV). Surface plasmon resonance (SPR) revealed that quercetin targets host ubiquitin-activating enzyme 1 (Uba1) homologs. Uba1 knockdown reduced viral proliferation and enhanced the antiviral effect of quercetin, whereas Uba1 overexpression functioned oppositely. Quercetin bound Uba1 homologs with high affinity. Notably, mutation of two binding residues, Q977 and G978, significantly disrupted the binding between BmUba1 and quercetin, and abolished quercetin's antiviral activity. Quercetin obstructed the transfer of ubiquitin from Uba1 to the E2 enzyme Ubc6, impairing the ubiquitination process. Similarly, quercetin inhibited PRRSV proliferation via targeting Uba1 in mammals. These findings elucidate the molecular mechanism underlying the pharmacological effects of quercetin, providing a theoretical basis for the development of novel antiviral agents against both DNA and RNA viruses.

Quercetin↗
PubMed2006

The site of vitellogenin synthesis in Chinese mitten-handed crab Eriocheir sinensis.

The objective of this study was to investigate the synthesis site of vitellogenin in the Chinese mitten-handed crab, Eriocheir sinensis. Using the RT-PCR techniques, the cDNA fragments isolated from the ovaries of vitellogenic female crab, we found that its deduced amino acid sequence had a high identity with that from other decapods crustacean vitellogenin. This cDNA fragments were used as probes to examine the transcription of mRNAs encoding the Vg. The mRNA expression was observed in vitellogenic female hepatopancreas, which was not detected in any other tissues including muscle, heart, and subepidermal tissues. The positive immunocytological staining with antibody against vitellin were found in ovaries and hepatopancreas of vitellogenic female, which was determined by immunological and immunohistochemical techniques. These results suggest that both ovaries and hepatopancreas are capable of synthesizing vitellogenin. Therefore, it was concluded that hepatopancreas is the extraovarian site of vitellogenin synthesis in E. sinensis.

Animals↗
PubMed2006

A hybrid forward algorithm for RBF neural network construction.

This paper proposes a novel hybrid forward algorithm (HFA) for the construction of radial basis function (RBF) neural networks with tunable nodes. The main objective is to efficiently and effectively produce a parsimonious RBF neural network that generalizes well. In this study, it is achieved through simultaneous network structure determination and parameter optimization on the continuous parameter space. This is a mixed integer hard problem and the proposed HFA tackles this problem using an integrated analytic framework, leading to significantly improved network performance and reduced memory usage for the network construction. The computational complexity analysis confirms the efficiency of the proposed algorithm, and the simulation results demonstrate its effectiveness.

Algorithms↗
PubMed2006

Optimal surface segmentation in volumetric images--a graph-theoretic approach.

Efficient segmentation of globally optimal surfaces representing object boundaries in volumetric data sets is important and challenging in many medical image analysis applications. We have developed an optimal surface detection method capable of simultaneously detecting multiple interacting surfaces, in which the optimality is controlled by the cost functions designed for individual surfaces and by several geometric constraints defining the surface smoothness and interrelations. The method solves the surface segmentation problem by transforming it into computing a minimum s-t cut in a derived arc-weighted directed graph. The proposed algorithm has a low-order polynomial time complexity and is computationally efficient. It has been extensively validated on more than 300 computer-synthetic volumetric images, 72 CT-scanned data sets of different-sized plexiglas tubes, and tens of medical images spanning various imaging modalities. In all cases, the approach yielded highly accurate results. Our approach can be readily extended to higher-dimensional image segmentation.

Algorithms↗
PubMed2006

Determination of liquiritin, naringin, hesperidin, thymol, imperatorin, honokiol, isoimperatorin, and magnolol in the traditional Chinese medicinal preparation Huoxiang-zhengqi liquid using high-performance liquid chromatography.

High-performance liquid chromatography was employed to determine the contents of the eight marker components liquiritin, naringin, hesperidin, thymol, imperatorin, honokiol, isoimperatorin, and magnolol in the traditional Chinese medicinal preparation Huoxiang-zhengqi liquid. The separation was performed on a C(18) column by stepwise gradient elution with water-methanol-acetonitrile (0.01 min, 68:30:2; 20 min, 60:38:2; 50 min, 34:64:2; 65 min, 34:64:2; 75 min, 28:70:2; 85 min, 68:30:2) as the mobile phase at a flow rate of 1 ml/min, with UV detection at 283 nm. Eight regression equations showed good linear relationships between the peak area ratio of each marker to internal standard and amounts. The recoveries of the markers listed above were 97.4, 98.5, 97.4, 98.6, 97.8, 99.2, 97.0, and 97.5%, respectively. The repeatability and reproducibility (relative standard deviation) of the method were less than 2.2 and 3.0%, respectively.

Biphenyl Compounds↗
PubMed2005

[Short circuit current technology and its application in the study of traditional Chinese medicine].

Short circuit current (I(sc)) technique has been applied in the studies of transepithelial ion transport in various epithelia. Recently it has also been used in the modernization researches on traditional Chinese medicines. This review gives an overview of the basic principle of the I(sc) technique, the targets of measurement, ion transport, ion channel, the general ways of I(sc) research design, the application of I(sc) technology in the researches on traditional Chinese medicines.

Animals↗
PubMed2005

Identification and expression of a new type II transmembrane protein in human mast cells.

A cDNA encoding a new type II transmembrane protein has been isolated from human mast cells by subtraction cloning. This cDNA contains an open reading frame of 186 amino acids. RT-PCR analysis showed that this gene is differentially expressed in mast cells. Therefore, the peptide encoded by this gene was termed mast cell-expressed membrane protein 1 (MCEMP1). The MCEMP1 gene contains seven exons and was mapped to human chromosome 19p13.3. The epitope-tagged MCEMP1 has been expressed in mammalian cells and found to be localized to the cellular membrane with its C-terminus extending to the outside of the membrane and N-terminus into the cytoplasmic compartment. Monoclonal antibodies against MCEMP1 were generated and characterized by immunoprecipitation and FACS. The results showed that the native MCEMP1 is expressed in cord blood-derived mast cells and HMC-1 and THP-1 cell lines, but not in other cell types that we have tested. Immunochemical staining of human lung sections showed that MCEMP1 staining is specifically associated with lung mast cells.

Alternative Splicing↗
PubMed2005

Amphiregulin expression in human mast cells and its effect on the primary human lung fibroblasts.

BACKGROUND: Amphiregulin is a member of the epidermal growth factor family and has been shown to stimulate the proliferation of human keratinocytes in an autocrine manner. OBJECTIVE: The aim of the present study was to examine the expression change of growth factors, especially amphiregulin, in human mast cells induced by IgE cross-linking. METHODS: Microarray analysis and RT-PCR were used to analyze the gene expression profile of human cord blood-derived mast cells (CBMCs) stimulated with IgE cross-linking. Protein secretion in the supernatants of CBMCs was measured by means of ELISA. Double-immunofluorescence staining was used to analyze the expression in the lung mast cells. RESULTS: Of the 64 different growth factor genes analyzed, 5 were found to be substantially upregulated. Among them, amphiregulin mRNA was induced by 44-fold in CBMCs on activation through IgE cross-linking. Secretion of amphiregulin protein was evident in CBMCs 8 hours after stimulation. Amphiregulin was also expressed in human lung mast cells from patients with asthma, as demonstrated by means of double-immunofluorescence staining. Amphiregulin promoted the proliferation of the primary human lung fibroblasts, and amphiregulin-treated primary human lung fibroblasts showed a marked increase in the expression of c-fos , a proto-oncogene that facilitates or is required for the proliferation of a wide variety of cells. CONCLUSION: Human CBMCs secreted amphiregulin on IgE cross-linking, and the amphiregulin induced proliferation of primary human lung fibroblasts. These data suggest that local release of amphiregulin by human mast cells could play an important role in lung fibrosis by promoting the proliferation of primary human lung fibroblasts.

Amphiregulin↗
PubMed2004

Purification of vitellin from the ovary of Chinese mitten-handed crab (Eriocheir sinensis) and development of an antivitellin ELISA.

Vitellin was purified from ovaries of mature female Chinese mitten-handed crab (Eriocheir sinensis) using gel filtration chromatography. Analysis by native PAGE showed the vitellin had a native molecular mass of 520 kDa, while denaturing SDS-PAGE revealed two subunits of 97 and 74 kDa. Purified vitellin was used to raise polyclonal antisera, with which an enzyme-linked immunosorbent assay (ELISA) was developed. The ELISA was sensitive and could effectively detect vitellin in the range of 7.8-500 ng. Furthermore, vitellin levels in various developmental stages of oogenesis were measured with the ELISA assay. The results indicated that levels of vitellin increased significantly from 0.22 mg/ovary at Stage II to 360.31 mg/ovary at Stage IV.

Animals↗
PubMed2004

Determination of mangiferin, jateorrhizine, palmatine, berberine, cinnamic acid, and cinnamaldehyde in the traditional Chinese medicinal preparation Zi-Shen pill by high-performance liquid chromatography.

High-performance liquid chromatography is employed to determine the contents of six marker components such as mangiferin, jateorrhizine, palmatine, berberine, cinnamic acid, and cinnamaldehyde in the traditional Chinese medicinal preparation Zi-Shen pill. The separation is performed on a C(18) column by stepwise gradient elution with water (0.2%, v/v, triethylamine adjusted to pH 4 with phosphoric acid)-methanol-acetonitrile (0.01 min, 98:0:2; 20 min, 80:5:15; 30 min, 65:13:22; and 55 min, 65:13:22) as the mobile phase at a flow rate of 0.9 mL/min, with UV detection at 280 nm. Six regression equations show good linear relationships between the peak area of each marker and concentration. The recoveries of the markers listed are 95.5%, 98.3%, 96.8%, 99.5%, 101.7%, and 102.1%, respectively. The repeatability and reproducibility (relative standard deviation) of the method are less than 2.5% and 3.3%, respectively.

Acrolein↗
PubMed2004

Reverse-phase HPLC determination and pharmacokinetic study of vanillic acid in the plasma of rats treated with the traditional Chinese medicinal preparation Di-Gu-Pi decoction.

A sensitive, simple, and accurate method for the determination and pharmacokinetic study of vanillic acid in rat plasma was developed using reverse-phase HPLC with UV detection after oral administration of the traditional Chinese medicine preparation of the Di-Gu-Pi decoction. Plasma samples taken from rats were extracted with methanol. The constituent vanillic acid was separated on a C(18) stationary phase and a mobile phase of acetonitrile-water (15:85, v/v) (adjusted to pH 3.0 using phosphoric acid), with a UV detector setting at 260 nm. The validated HPLC method developed was used to determine the pharmacokinetic profile of vanillic acid in rat plasma after administration of the Di-Gu-Pi decoction.

Administration, Oral↗
PubMed2003

Calcineurin/nuclear factors of activated T cells (NFAT)-activating and immunoreceptor tyrosine-based activation motif (ITAM)-containing protein (CNAIP), a novel ITAM-containing protein that activates the calcineurin/NFAT-signaling pathway.

We report in this study the identification and characterization of a novel protein that we designated as calcineurin/NFAT-activating and immunoreceptor tyrosine-based activation motif (ITAM)-containing protein (CNAIP). The predicted 270-amino acid sequence contains an N-terminal signal peptide, an immunoglobin domain in the extracellular region, a transmembrane domain and an ITAM in the cytoplasmic tail. Quantitative reverse transcription-PCR showed that CNAIP was preferentially expressed in neutrophils, monocytes, mast cells, and other immune-related cells. Co-transfection of CNAIP expression constructs with luciferase reporter plasmids in HMC-1 cells resulted in activation of interleukin-13 and tumor necrosis factor-alpha promoters, which was mediated through the calcineurin/NFAT-signaling pathway. Mutation of either or both tyrosines in the ITAM abolished transcriptional activation induced by CNAIP, indicating that the ITAM is indispensable for CNAIP function in activating cytokine gene promoters. Thus, it is concluded that CNAIP is a novel ITAM-containing protein that activates the calcineurin/NFAT-signaling pathway and the downstream cytokine gene promoters.

Amino Acid Sequence↗
PubMed2002

Cardiac dysfunction in mice lacking cytochrome-c oxidase subunit VIaH.

Cytochrome-c oxidase subunit VIaH (COXVIaH) has been implicated in the modulation of COX activity. A gene-targeting strategy was undertaken to generate mice that lacked COXVIaH to determine its role in regulation of oxidative energy production and mechanical performance in cardiac muscle. Total COX activity was decreased in hearts from mutant mice, which appears to be a consequence of altered assembly of the holoenzyme COX. However, total myocardial ATP was not significantly different in wild-type and mutant mice. Myocardial performance was examined using the isolated working heart preparation. As left atrial filling pressure increased, hearts from mutant mice were unable to generate equivalent stroke work compared with hearts from wild-type mice. Direct measurement of left ventricular end-diastolic volume using magnetic resonance imaging revealed that cardiac dysfunction was a consequence of impaired ventricular filling or diastolic dysfunction. These findings suggest that a genetic deficiency of COXVIaH has a measurable impact on myocardial diastolic performance despite the presence of normal cellular ATP levels.

Animals↗
PubMedDate not supplied

Human motion capture data compression by model-based indexing: a power aware approach.

Human Motion Capture (MoCap) data can be used for animation of virtual human-like characters in distributed virtual reality applications and networked games. MoCap data compressed using the standard MPEG-4 encoding pipeline comprising of predictive encoding (and/or DCT decorrelation), quantization, and arithmetic/Huffman encoding, entails significant power consumption for the purpose of decompression. In this paper, we propose a novel algorithm for compression of MoCap data, which is based on smart indexing of the MoCap data by exploiting structural information derived from the skeletal virtual human model. The indexing algorithm can be fine-controlled using three predefined quality control parameters (QCPs). We demonstrate how an efficient combination of the three QCPs results in a lower network bandwidth requirement and reduced power consumption for data decompression at the client end when compared to standard MPEG-4 compression. Since the proposed algorithm exploits structural information derived from the skeletal virtual human model, it is observed to result in virtual human animation of visually acceptable quality upon decompression.

Algorithms↗