Biomedical subjects

Yang Gao

Publications and source records attributed to Yang Gao.

At least 19 recordsLinked to original sources

PubMed2026

Identification and characterization of anti-chikungunya virus compounds using a biosafe toolkit.

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus for which no specific antiviral therapy is currently available. During the large outbreak in Foshan, Guangdong Province, China, in July 2025, CHIKV rapidly spread to neighboring regions and caused more than 16,000 confirmed cases. In this study, the predominant outbreak strain of CHIKV was selected as the reference sequence to establish a panel of complementary biosafe tools for antiviral compound screening and mechanistic investigation. A virus replicon particle (VRP) system for CHIKV was first constructed and applied to compound library screening, resulting in the identification of three candidate antiviral compounds: MDL-12330A, bazedoxifene acetate, and anidulafungin. To further validate their antiviral activities and investigate their potential mechanisms, CHIKV functional evaluation systems were subsequently established, including vesicular stomatitis virus (VSV)- and murine leukemia virus (MLV)-based pseudovirus systems for viral entry, a replicon RNA system for post-entry replication-associated processes, a replication-defective nsP4 mutant replicon RNA system for primary translation, and a virus-like particle (VLP) system for viral particle assembly and budding assessment. Using these complementary systems, we systematically evaluated the antiviral profiles of the three candidate compounds across multiple stages of the CHIKV life cycle. This analysis revealed distinct stage-specific inhibitory patterns and provided insights into their potential antiviral mechanisms, which warrant validation using authentic CHIKV infection to assess their translational potential.

Chikungunya virus↗

PubMed2026

Expression of PIEZO1 in lung adenocarcinoma correlates with PD-L1 expression, cell migration, and poor prognosis: an exploratory study.

BACKGROUND AND AIMS: Lung adenocarcinoma (LUAD) treatment is challenging process. and the function of PIEZO1, a mechanically sensitive ion channel has not been systematically determined. In this study we aimed to explore the expression, potential associations, and clinical significance of PIEZO1 in LUAD. METHODS AND AIMS: A comprehensive bioinformatics analysis was performed using data from the Cancer Genome Atlas (TCGA) database, the Gene Expression Omnibus (GEO) database and other databases. Experimental validation was performed to confirm the expression patterns and preliminarily examine the associations of PIEZO1 in LUAD cell lines. RESULTS: PIEZO1 expression was significantly lower in LUAD tissues than in normal lung tissues (P < 0.05). Its expression was correlated with advanced pathological stage, lymph node involvement, and distant metastasis. High PIEZO1 expression was associated with a distinct immune-related tumor microenvironment, characterized by correlations with the expression levels of multiple immune checkpoint molecules, and was identified as an independent factor associated with poor overall survival (HR = 1.49; 95% CI 1.11-2; P < 0.007). In vitro experiments confirmed the downregulated PIEZO1 expression in LUAD cell lines, and functional knockdown experiments revealed its association with cell migration and PD-L1 expression. CONCLUSION: This exploratory study revealed that PIEZO1 expression in LUAD cell lines correlated with the expression of immune-related features and EMT-related genes, as well as poor prognosis. In vitro, PIEZO1 knockdown is associated with reduced cell migration and decreased PD-L1 expression. These findings provide a basis for future investigations into the potential role of PIEZO1 in LUAD.

Gene expression↗

PubMed2026

Region-Resolved Integrative Multi-Omic Characterization Reveals Diverse Tumor and Microenvironment Features of Pituitary Neuroendocrine Tumors.

Pituitary neuroendocrine tumors are frequently invasive, with cavernous sinus invasion leading to poor treatment outcomes and high recurrence. Regional differences within these tumors remain poorly understood, hindering targeted therapy development. Here, we present the first integrative multi-omics analysis combining proteomics, metabolomics and single-cell transcriptomics to characterize tumors from the cavernous sinus and saddle regions. Our results reveal profound regional and cellular heterogeneity: cavernous sinus tumors exhibit significantly enhanced cell proliferation, driven by cancer-associated fibroblasts through the IGF1-IGF1R-MAPK1 axis. Cancer-associated fibroblasts in the cavernous sinus secrete IGF1 under regulation of the transcription factor FOXO1, which binds to receptors on tumor cells to activate proliferation. Metabolomic profiling identifies proline as a key enriched metabolite that stimulates cancer-associated fibroblasts to produce collagen fibers, reinforcing a pro-tumorigenic microenvironment. Single-cell transcriptomics further delineates a distinct subpopulation of receptor-positive malignant cells and a high abundance of cancer-associated fibroblasts in the cavernous sinus. These findings establish core mechanisms underlying the aggressive behavior of cavernous sinus-invading tumors, providing novel actionable targets for precision therapeutic strategies tailored to distinct tumor regions.

Humans↗

PubMed2025

Heme oxygenase 1 (HO-1) is a drug target for reversing cisplatin resistance in non-small cell lung cancer.

INTRODUCTION: Platinum-based drugs, the most widely used chemotherapeutic drugs in clinical oncology, have long faced the problem of drug resistance, which is urgently in need of resolution. Identifying biomarkers of drug resistance may help reduce platinum resistance and improve therapeutic efficacy. OBJECTIVES: This study aims to identify potential biomarkers associated with the development of cisplatin resistance in non-small cell lung cancer (NSCLC) and explore mechanisms to overcome chemoresistance. METHODS: NSCLC cisplatin resistance cell lines were constructed, and transcriptome sequencing was performed. Results were validated using Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Molecular docking, proteomics sequencing, and in vitro and in vivo experiments were conducted to evaluate the role of Heme Oxygenase 1 (HO-1) in cisplatin resistance. RESULTS: NSCLC cisplatin resistance cell lines, GEO and TCGA data identified HMOX1, downstream of Nrf2, as a key drug resistance gene induced by cisplatin. Activation of the Nrf2/HO-1 pathway was found to induce ferroptosis resistance, a critical mechanism of cisplatin resistance. Candidate compounds SB 202190 and Nordihydroguaiaretic acid (NDGA) effectively reactivated ferroptosis by inhibiting HO-1, thereby increasing cisplatin sensitivity. CONCLUSION: The Nrf2/HO-1 pathway is a significant contributor to cisplatin resistance in NSCLC. Targeting HO-1 with SB 202190 and NDGA presents a promising strategy to overcome resistance and improve chemotherapy outcomes.

Cisplatin↗

PubMed2006

Haplotypes in matrix metalloproteinase gene cluster on chromosome 11q22 contribute to the risk of lung cancer development and progression.

PURPOSE: Matrix metalloproteinases (MMP) play important roles in cancer development and single nucleotide polymorphisms (SNP) in some MMP genes were shown to confer susceptibility to certain cancers. This study examined the association between genotypes and haplotypes in the MMP1-MMP3-MMP12 gene cluster and risk of lung cancer development and metastasis. EXPERIMENTAL DESIGN: A two-stage investigation was conducted. First, 35 SNPs covering these genes were selected and validated in 190 patients and 190 controls. Twenty-two validated SNPs were then analyzed in an entire case-control panel consisting of 711 patients and 716 controls. Associations with the risk of lung cancer were estimated by logistic regression. RESULTS: The investigated MMP gene region could be partitioned into two major haplotype blocks. One common haplotype in the block composed of major part of MMP1 transcription region was significantly associated with increased risk for the development [odds ratio (OR), 1.35; 95% confidence interval (95% CI), 1.11-1.63; P = 0.01; permutated P = 0.134] and distant metastasis of lung cancer (ORs for stage IV versus stages I-III, 1.67; 95% CI, 1.12-2.50; P = 0.009; permutated P = 0.048) and the other showed a protective effect against metastasis (ORs for stage IV versus stages I-III, 0.22; 95% CI, 0.07-0.62; P = 0.001; permutated P = 0.011). Another common haplotype in the block across MMP3 was significantly associated with decreased risk for developing lung cancer (OR, 0.71; 95% CI, 0.59-0.86; P = 0.003; permutated P = 0.027). CONCLUSIONS: The observed multiple cancer-associated genetic variants suggested that the MMP1-MMP3-MMP12 gene cluster plays important roles in lung cancer development and progression.

Adult↗

PubMed2006

Selection of SARS-coronavirus-specific B cell epitopes by phage peptide library screening and evaluation of the immunological effect of epitope-based peptides on mice.

Antibodies to SARS-Coronavirus (SARS-CoV)-specific B cell epitopes might recognize the pathogen and interrupt its adherence to and penetration of host cells. Hence, these epitopes could be useful for diagnosis and as vaccine constituents. Using the phage-displayed peptide library screening method and purified Fab fragments of immunoglobulin G (IgG Fab) from normal human sera and convalescent sera from SARS-CoV-infected patients as targets, 11 B cell epitopes of SARS-CoV spike glycoprotein (S protein) and membrane protein (M protein) were screened. After a bioinformatics tool was used to analyze these epitopes, four epitope-based S protein dodecapeptides corresponding to the predominant epitopes were chosen for synthesis. Their antigenic specificities and immunogenicities were studied in vitro and in vivo. Flow cytometry and ELISPOT analysis of lymphocytes as well as a serologic analysis of antibody showed that these peptides could trigger a rapid, highly effective, and relatively safe immune response in BALB/c mice. These findings might aid development of SARS diagnostics and vaccines. Moreover, the role of S and M proteins as important surface antigens is confirmed.

Amino Acid Sequence↗

PubMed2006

Secondary structure effects on DNA hybridization kinetics: a solution versus surface comparison.

The hybridization kinetics for a series of designed 25mer probe-target pairs having varying degrees of secondary structure have been measured by UV absorbance and surface plasmon resonance (SPR) spectroscopy in solution and on the surface, respectively. Kinetic rate constants derived from the resultant data decrease with increasing probe and target secondary structure similarly in both solution and surface environments. Specifically, addition of three intramolecular base pairs in the probe and target structure slow hybridization by a factor of two. For individual strands containing four or more intramolecular base pairs, hybridization cannot be described by a traditional two-state model in solution-phase nor on the surface. Surface hybridization rates are also 20- to 40-fold slower than solution-phase rates for identical sequences and conditions. These quantitative findings may have implications for the design of better biosensors, particularly those using probes with deliberate secondary structure.

DNA Probes↗

PubMed2006

Viral transduction of cocaine hydrolase in brain reward centers.

1. Site-directed mutagenesis of human plasma butyrylcholinesterase has led to novel hydrolases that rapidly destroy cocaine. We are investigating whether viral gene transfer of such enzymes might reduce addiction liability by blocking cocaine from its sites of action. 2. As groundwork for a possible gene therapy, we previously studied adenoviral transduction of cocaine hydrolases in the rat. Systemically injected vectors raised plasma cocaine hydrolase activity greatly, reduced pressor responses to cocaine, and lowered cocaine's tissue burden. 3. In the present study, to reduce cocaine's brain access still further, vectors were injected directly into the nucleus accumbens. Six days later, medium sized neurons gained dramatic butyrylcholinesterase activity. Species-selective immunohistochemistry proved that the transgene accounted for this activity. 4. Since the transgene product is so efficient with cocaine as a substrate, it is now reasonable to begin testing gene therapy in rodent models of cocaine addiction.

Adenoviridae↗

PubMed2006

Role of T-cell receptor V beta 8.3 peptide vaccine in the prevention of experimental autoimmune uveoretinitis.

BACKGROUND: T-cell receptor (TCR) plays an important role in the development of autoimmune diseases. Recently, it was reported that immunization of animals with TCR peptide derived from the pathogenic cells could prevent autoimmune diseases. The aim of this study was to investigate whether vaccination with a synthetic peptide from the hypervariable region of TCR V(beta) 8.3, an experimental autoimmune uveoretinitis (EAU)-associated gene, was able to prevent the disease. METHODS: EAU was induced in Lewis rats by immunization with IRBP R16 peptide emulsified in complete Freund's adjuvant (CFA). The clinical and histological appearances were scored. Delayed type hypersensitivity (DTH) and lymphocyte proliferation were detected. Cytokine levels of aqueous humour, supernatants of cells from spleen and draining lymph nodes were measured by enzyme linked immunosorbent assay (ELISA). Gene expression of TCR V(beta) 8.3 on CD(4)(+) T cells was examined by real time quantitative polymerase chain reaction (PCR). RESULTS: After vaccination, the intraocular inflammation was significantly mitigated, antigen specific DTH and lymphocyte proliferation responses were suppressed, interleukin (IL)-2 in aqueous humour, interferon (IFN)-gamma and IL-2 produced by the spleen and draining lymph node cells were significantly decreased, whereas the production of IL-4 and IL-10 were increased. The response of draining lymph node cells to TCR V(beta) 8.3 peptide was enhanced after vaccination. Inoculation with CFA alone did not affect the severity of EAU and the above parameters. The suppression of EAU was much stronger in the group of four fold inoculations than the group of two fold inoculations. The expression of TCR V(beta) 8.3 gene was significantly reduced in the group of fourfold inoculations. CONCLUSION: Vaccination with the synthetic TCR V(beta) 8.3 peptide could remarkably inhibit the development of EAU.

Animals↗

PubMed2006

Relationship between human sperm-hyaluronan binding assay and fertilization rate in conventional in vitro fertilization.

BACKGROUND: Sperm-hyaluronan-binding assay (HBA) is one of the commercial kits being marketed for routine testing of sperm maturity and fertility. However, there is no report of whether the HBA can provide additional information over standard semen analysis for sperm-fertilizing ability. The objective of this study was to investigate the relationship between HBA and fertilization rate in conventional IVF. METHODS: A total of 175 IVF patients with > or = 3 mature oocytes inseminated were included in the study. Both the standard semen analysis and the HBA were performed on the same ejaculated sperm samples used for IVF treatments. Relationships between the semen analysis and the HBA results and fertilization rate were analysed by both the Spearman test and the multivariate logistic regression analysis. RESULTS: Both total and progressive sperm motility and normal morphology were highly correlated with HBA scores. While both normal sperm morphology and HBA scores were statistically significantly related to fertilization rates, the HBA was less significant than normal sperm morphology. The HBA does not provide additional information for identifying patients with a poor fertilization rate. CONCLUSION: HBA is highly significantly correlated with sperm motility and morphology but is less significant than sperm morphology in relation to the fertilization rate in IVF. Thus, the clinical predictive value of HBA for sperm-fertilizing ability in vitro is limited.

Female↗

PubMed2006

OVA-specific CD8+ T cells do not express granzyme B during anterior chamber associated immune deviation.

PURPOSE: To examine antigen (Ag)-specific CTL response during anterior chamber associated immune deviation (ACAID). METHODS: OVA or OVA257-264 peptide was injected into the anterior chamber (AC) of C57BL/6 mice. There were 16 mice in each ACAID group induced with OVA or OVA257-264 peptide. The mice were primed by SC injection with OVA or OVA 257-264 peptide in complete Freund's adjuvant (CFA) on day 7. Ag-specific CD8+ T cells in spleens were analyzed on day 14 using Pentamer H-2K(b)-SIINFEKL(OVA257-264 peptide). IFN-gamma ELISPOT and intracellular granzyme B staining were used to characterize the CTL response. Twelve mice in each group immunized with OVA or OVA257-264 peptide in CFA served as positive controls. Twelve normal mice served as negative controls and 12 receiving injection of CFA as CFA controls for studying the influence of CFA on the Ag-specific CTL response. RESULT: The results showed that anterior chamber inoculation of OVA or OVA257-264 peptide could induce ACAID as evidenced by an impaired DTH response. The frequency of Ag-specific CD8+ T cells in ACAID mice was not different from that in mice challenged with Ags in CFA only (positive controls). IFN-gamma production by these cells in ACAID mice was not different compared to positive controls. However, Ag-specific CD8+ T cells in ACAID mice failed to secrete granzyme B. Mice challenged only with OVA peptide and CFA also showed a granzyme B negative CD8+ T cell response. Ag-specific CTL response induced by CFA alone was similar with the negative control. CONCLUSION: These results show that the frequency of Ag-specific CD8+ T cells is not altered during ACAID. The Ag-specific CTL response during ACAID is characterized by the absence of granzyme B expression.

Animals↗

PubMed2006

Detection of serum neopterin for early assessment of dengue virus infection.

OBJECTIVE: Neopterin is generated and released in increased amounts by macrophages upon activation by interferon-gamma during Th1-type immune response. The potential usefulness of neopterin in early prognostic information of dengue virus infection was investigated. METHODS: Neopterin concentrations were determined in serum samples from 110 dengue fever (DF) patients. The neopterin levels were compared with those in 50 measles and 40 influenza patients; 155 healthy blood donors served as controls. RESULTS: In acute sera of DF patients mean neopterin concentration was 48.2 nmol/L, which was higher than that in patients with measles (mean: 36.3 nmol/L) and influenza (18.8 nmol/L) and in healthy controls (6.7 nmol/L; P<0.001). In the patients with confirmed DF, an early neopterin elevation was detected already at the first day after the onset of symptoms and rose to a maximum level of 54.3 nmol/L 4 days after the onset. Higher increase of neopterin level in DF patients was associated with longer duration of fever and thus predicted the clinical course of the disease. CONCLUSIONS: Neopterin concentrations were found significantly higher in DF patients compared with healthy controls and also with other viral infections (P<0.001) and may allow early assessment of the severity of DF.

Adolescent↗

PubMed2006

Inducible co-stimulator (ICOS) is upregulated in experimental autoimmune uveoretinitis.

PURPOSE: To study the expression of inducible co-stimulator (ICOS) and its association with T cell effector function in experimental autoimmune uveoretinitis (EAU). METHODS: Eighteen Lewis rats were immunized by retinal S-antigen (50 microg) emulsified in complete Freund's adjuvant (CFA). Twelve normal rats served as normal controls and 18 receiving injection of CFA and PBS as CFA controls for studying the influence of CFA on the expression of ICOS in CD4+CD25+ T cells. ICOS expression on cells from the spleens, inguinal nodes and retinae on day 0 (normal rats), 7, 13 and 21 was investigated using fluorescent quantitative real-time-PCR and Western blot. Expression of B7RP-1, an ICOS ligand, was also studied by Western blot. The phenotype of the cells from the aforementioned three tissues was identified with flow cytometry using antibodies to ICOS, CD4 and CD25. ICOS+ cells from the lymph nodes, and spleens on day 13 were magnetically sorted and cultured with S-antigen to study the cytokines production with enzyme-linked immunosorbent assay. RESULT: An obvious uveitis was induced in all the immunized rats on day 13 after S-antigen immunization. The mRNA and protein of ICOS were scarcely detectable in normal rat spleens. In EAU rats, an up-regulation of ICOS could be observed on day 7 and was very pronounced on day 13, followed by a decrease on day 21 in the spleens, draining nodes and retinae. Similarly, B7RP-1 expression seemed to be up-regulated during EAU. Flow cytometry showed that ICOS+ cells were mostly CD4 positive. Kinetics of ICOS+CD4+CD25+ T cells was similar to that of ICOS+ cells. CFA alone was also able to induce increased expression of ICOS in CD4+CD25+ T cells. IFN-gamma was secreted predominantly by ICOS+ T cells. CONCLUSION: ICOS expression is up-regulated in association with T cell effector capacity in EAU. It is presumed that the ICOS/B7RP-1 costimulatory pathway may play a role in the development of EAU.

Animals↗

PubMed2006

The nonspecific anti-inflammatory therapy with methotrexate for patients with chronic heart failure.

BACKGROUND: Inflammatory mediators play an important role in the pathogenesis of chronic heart failure (CHF). Methotrexate (MTX) is used in the treatment of inflammatory-mediated diseases (eg, rheumatoid arthritis) because it modulates the expression of numerous inflammatory cytokines. However, no studies have assessed the effects of MTX on plasma levels of inflammatory mediators in patients with CHF. METHODS: In a prospective, randomized, placebo-controlled, single-blind study, 71 patients receiving conventional treatment were randomly allocated to either MTX group (7.5 mg once a week, n = 35) or placebo group (n = 36) with a follow-up of 12 weeks. The effects of MTX on plasma cytokine expression, left ventricular ejection fraction, left ventricular end-diastolic dimension, New York Heart Association (NYHA) functional class, 6-minute walk test distance, and quality of life (QOL) were determined in patients with CHF. RESULTS: Sixty-two patients completed the study. The circulating levels of inflammatory mediators in patients with CHF were markedly elevated compared with healthy controls (P < or = .002). Methotrexate (n = 30) reduced plasma levels of tumor necrosis factor alpha (-15.6%, P < .05), interleukin 6 (-21.8%, P < .01), monocyte chemoattractant protein-1 (-22.6%, P < .01), soluble intercellular adhesion molecule-1 (-19.2%, P < .05), and C-reactive protein (-27.2%, P < .01) compared with baseline. Furthermore, interleukin 10 (15.8 %, P < .05) and soluble IL-1 receptor antagonist (36.1%, P < .01) expression was increased, whereas improvements in NYHA classification, 6-minute walk test distance, and QOL were found compared with baseline. Monocyte chemoattractant protein-1 expression was lower and soluble IL-1 receptor antagonist expression higher in the MTX than placebo group (n = 32). Furthermore, the left ventricular ejection fraction, left ventricular end-diastolic dimension, and incidence of main adverse cardiac events between the 2 groups were similar. CONCLUSION: These results suggest that the addition of MTX to conventional therapy for CHF has significant anti-inflammatory effects and improves NYHA functional class, 6-minute walk test distance, and QOL.

Anti-Inflammatory Agents↗

PubMed2006

[Immobilization of lipase on macroporous resin and its application in synthesis of biodiesel in low aqueous media].

Lipase from Candida sp. 99-125 was immobilized by physical adsorption onto macroporous resins. The results showed that the nonpolar resin NKA was the best carrier used in low aqueous media. 98.98% of degree of immobilization can be achieved when the adsorption procedure was performed in the presence of heptane. The hydrolytic activity and the apparent activity recovery of lipase adsorbed on resin in heptane was 4.07 and 3.43 times higher than that of lipase adsorbed in sodium phosphate buffer, respectively. The catalytic properties of immobilized lipase for production of biodiesel in low aqueous media were studied. Immobilized lipase displayed the highest activity when the crude enzyme/resin weight ratio was 1.92:1 and the water content(water/oil weight ratio) was 15% at 40 degrees C under pH 7.4. As lipase was adsorbed on NKA in heptane to produce biodiesel, the batch conversion rate can reach 97.3% when a three-step methanolysis protocol was used. After 19 consecutive batches, the conversion rate remained 70.2%.

Candida↗

PubMed2005

Visualizing viral transduction of a cocaine-hydrolyzing, human butyrylcholinesterase in rats.

Human plasma butyrylcholinesterase (BChE) is essential for cocaine detoxification even though its catalytic efficiency for that substrate is relatively poor. Site-directed mutagenesis of this protein has recently been used to obtain much-improved cocaine esterases, one of which we designate CocE. We previously showed that adenoviral transduction of such esterases caused up to 50,000-fold increases in circulating cocaine hydrolase activity, led to drastically shortened cocaine half-life, and blunted the cardiovascular responses to cocaine in rats. In those experiments, gene transduction of cocaine esterase was sustained at high levels for up to 1 week but then declined steeply. Our eventual goal is to use long-term esterase expression as a means of reducing drug reward and extinguishing intake in models of cocaine-addiction. Therefore, we investigated the site of enzyme transduction for clues to the local reactions that may limit the duration of CocE expression. Histological and immunohistochemical observations demonstrated that hepatocytes were the primary focus for transduction of modified human BChE. Rats were administered 2.2 x 10(10) plaque forming units of a replication-incompetent, type-5 adenoviral vector incorporating CocE cDNA. Within days the livers showed intense thiocholine staining for BChE activity. Selective immunohistochemistry for human BChE proved that this activity represented CocE transgene. By 5 days, however, pockets of mononuclear cells had invaded the hepatic parenchyma, and a meshwork of IgM-like immunoreactivity had lined the hepatic sinusoids. These phenomena probably represent early responses of the immune system, either to the transduced CocE or to the hepatocytes producing this protein.

Adenoviridae↗

PubMed2005

Beta-endorphin ameliorates synovial cell hyperfunction in the collagen-induced arthritis rat model by specific downregulation of NF-kappa B activity.

OBJECTIVES: To observe the multiple immunoregulating effects of beta-endorphin (beta-END) on synovium cells of collagen-induced arthritis (CIA) in rats and to determine whether the regulation involves the transcriptional factor-kappaB (NF-kappaB) signal pathway. METHODS: CIA was induced in female Wistar rats by immunization with native bovine type-II collagen emulsified with complete Freund's adjuvant. Synovial cells in the knees of the CIA rats were cultivated, and the effects of beta-END, beta-END receptor inhibitor (naloxone, Nal) in proliferation and apoptosis of the synovial cells were assayed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, flow cytometry, and DNA integrity, respectively. The effects of beta-END and Nal on mRNA expression of several cytokines in the synovial cells, including tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, regulated upon activation normal T-cell expressed and secreted (RANTES), inducible nitric oxide synthase (iNOS), matrix metalloproteinase-2 (MMP-2) and MMP-9 were estimated by quantitative reverse transcription-polymerase chain reaction. Effects of beta-END and Nal on NF-kappaB activity were analyzed using luciferase gene reporter assays. The effects of beta-END and Nal on p65NF-kappaB expression of the synovial cells were examined using Western blot. RESULTS: 75% of the rats were demonstrated to have established the CIA model successfully. beta-END was shown to exert multiple effects on synovial cells of CIA rats including decreased proliferation, induced apoptosis, and downregulation of TNF-alpha, IL-1beta, IL-6, RANTES, iNOS, MMP-2 and MMP-9 mRNA expression. beta-END seemed to play an immunoregulating role by downregulating the activity and expression of NF-kappaB. It was found that the beta-END receptor blockage could counteract all the effects. CONCLUSIONS: beta-END ameliorates synovial cell functions of CIA rats through binding with receptors and downregulating the NF-kappaB signal pathway. This suggests that beta-END, by blocking the activity and expression of NF-kappaB, is a potential anti-inflammatory and anti-rheumatic agent against CIA.

Analysis of Variance↗

PubMed2005

Cross-host evolution of severe acute respiratory syndrome coronavirus in palm civet and human.

The genomic sequences of severe acute respiratory syndrome coronaviruses from human and palm civet of the 2003/2004 outbreak in the city of Guangzhou, China, were nearly identical. Phylogenetic analysis suggested an independent viral invasion from animal to human in this new episode. Combining all existing data but excluding singletons, we identified 202 single-nucleotide variations. Among them, 17 are polymorphic in palm civets only. The ratio of nonsynonymous/synonymous nucleotide substitution in palm civets collected 1 yr apart from different geographic locations is very high, suggesting a rapid evolving process of viral proteins in civet as well, much like their adaptation in the human host in the early 2002-2003 epidemic. Major genetic variations in some critical genes, particularly the Spike gene, seemed essential for the transition from animal-to-human transmission to human-to-human transmission, which eventually caused the first severe acute respiratory syndrome outbreak of 2002/2003.

Amino Acid Substitution↗