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1.
Dalton Trans ; 52(43): 15968-15973, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37846746

ABSTRACT

Insights into the relationship between the crystal structure and activity of metal-organic frameworks (MOFs) are meaningful to investigate the potential properties of pristine MOFs for targeted catalytic reactions. Herein, we develop a high-efficiency method for boosting the oxidative desulfurization (ODS) activity of Ti-MOF in the presence of H+. The ODS activity of pristine Ti-MOF prepared via a solvothermal approach is very poor at a low reaction temperature but can be enhanced in the presence of H+. Ti-MOF in the presence of H+ shows ultrahigh ODS activity that can eliminate 1000 ppm sulfur after 7 min at 30 °C with no catalytic activity loss after recycling 11 times. The turnover frequency value reaches 12.4 h-1 at 30 °C, surpassing all the previously reported Ti-MOFs as ODS catalysts even at high temperatures. Characterization and quenching experimental results indicate that more uncoordinated Ti sites can be formed from slight damage to the structure of Ti-MOF during the catalytic reaction, and such exposed Ti sites can easily react with H+ and H2O2 to form Ti-hydroperoxo active species that determine the upgradation of ODS activity. This work provides a significant way to upgrade the catalytic activity of pristine Ti-MOFs for future application.

2.
Front Immunol ; 13: 868724, 2022.
Article in English | MEDLINE | ID: mdl-35603169

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging virus responsible for the ongoing COVID-19 pandemic. SARS-CoV-2 binds to the human cell receptor angiotensin-converting enzyme 2 (ACE2) through its receptor-binding domain in the S1 subunit of the spike protein (S1-RBD). The serum levels of autoantibodies against ACE2 are significantly higher in patients with COVID-19 than in controls and are associated with disease severity. However, the mechanisms through which these anti-ACE2 antibodies are induced during SARS-CoV-2 infection are unclear. In this study, we confirmed the increase in antibodies against ACE2 in patients with COVID-19 and found a positive correlation between the amounts of antibodies against ACE2 and S1-RBD. Moreover, antibody binding to ACE2 was significantly decreased in the sera of some COVID-19 patients after preadsorption of the sera with S1-RBD, which indicated that antibodies against S1-RBD can cross-react with ACE2. To confirm this possibility, two monoclonal antibodies (mAbs 127 and 150) which could bind to both S1-RBD and ACE2 were isolated from S1-RBD-immunized mice. Measurement of the binding affinities by Biacore showed these two mAbs bind to ACE2 much weaker than binding to S1-RBD. Epitope mapping using synthetic overlapping peptides and hydrogen deuterium exchange mass spectrometry (HDX-MS) revealed that the amino acid residues P463, F464, E465, R466, D467 and E471 of S1-RBD are critical for the recognition by mAbs 127 and 150. In addition, Western blotting analysis showed that these mAbs could recognize ACE2 only in native but not denatured form, indicating the ACE2 epitopes recognized by these mAbs were conformation-dependent. The protein-protein interaction between ACE2 and the higher affinity mAb 127 was analyzed by HDX-MS and visualized by negative-stain transmission electron microscopy imaging combined with antigen-antibody docking. Together, our results suggest that ACE2-cross-reactive anti-S1-RBD antibodies can be induced during SARS-CoV-2 infection due to potential antigenic cross-reactivity between S1-RBD and its receptor ACE2.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Animals , Antibodies, Monoclonal , Antibodies, Viral , Humans , Mice , Pandemics , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
3.
Hematology ; 26(1): 976-984, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34871535

ABSTRACT

Multiple myeloma (MM) is one of the most common types of hematologic malignancy for which the underlying molecular mechanisms remain largely unclear. Dysregulated miRNA expression has been shown to be involved in MM tumorigenesis, progression and drug response. Therefore, a comprehensive analysis based on miRNA-level integrated strategy was performed.This study aimed to elucidate key miRNA signatures and pathways in MM by integrated bioinformatics analysis. Expression profiles GSE24371, GSE49261 and GSE54156 were obtained from the Gene Expression Omnibus database, and differentially expressed miRNAs (DEMirs) with p < 0.05 were identified. The target genes of these DEMirs were obtained from ENCORI database, and functional enrichment, subpathway enrichment and protein-protein interaction network construction were performed. The key target genes were identified by random walk algorithm and survival verification was performed.and discussion: First, six up-regulated and four down-regulated DEMirs shared between any two GSE data sets were identified. Second, target genes (DEMirTGs) by up-regulated and down-regulated DEMirs were obtained. Functional and subpathway enrichment analysis showed that these up-regulated DEMirs are consistently involved in the Wnt signaling pathway. Moreover, enrichment of the down-regulated DEMirs is mainly in the MAPK signaling pathway. Finally, a protein-protein interaction sub-network for these DEMirTGs was constructed, the correlations between the two key genes were identified and survival in MM was evaluated using multiple independent data sets.We identified miRNA signatures and key target genes that were closely related to MM biology, and these genes might serve as potential therapeutic targets for MM patients.


Subject(s)
Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , MicroRNAs/genetics , Multiple Myeloma/genetics , Gene Expression Profiling , Genomics , Humans , Multiple Myeloma/metabolism , Protein Interaction Maps , Signal Transduction
4.
J Orthop Surg Res ; 16(1): 637, 2021 Oct 24.
Article in English | MEDLINE | ID: mdl-34689803

ABSTRACT

OBJECTIVE: This study was to explore the effect of exosomal miR-155 derived from bone marrow mesenchymal stem cells (BMSCs) on stemness maintenance and drug resistance in MPC-11 multiple myeloma cells. METHODS: MPC-11 cells were transfected with mimics or inhibitors of miR-155. miR-155 expression was detected by qRT-PCR, cell condition was observed, and the expression of stemness maintenance markers OCT-4 and Nanog was observed by immunofluorescence. The expression of proteins associated with the Hedgehog signaling pathway and drug resistance was evaluated by western blot. To investigate whether exosomes affect cell behavior by horizontal delivery of miR-155, MPC-11 cells were co-cultured with exosomes isolated from BMSCs that were transfected with mimics or inhibitors of miR-155. Cell proliferation and the expression of proteins related to stemness maintenance protein and drug resistance were examined. RESULTS: In function assays, after miR-155-mimics transfection, the expression levels of proteins related to stemness maintenance marker, Hedgehog signaling, and drug resistance were increased in MPC-11 cells. BMSC-derived exosomes carrying miR-155 inhibited apoptosis, promoted cell division, and upregulated the expression of protein associated with stemness maintenance, Hedgehog signaling, and drug resistance. CONCLUSION: Therefore, our findings indicate that exosomal delivery of miR-155 exerted the same effect as transfection did on the stemness maintenance and drug resistance of multiple myeloma cells.


Subject(s)
Mesenchymal Stem Cells , MicroRNAs , Multiple Myeloma , Bone Marrow Cells , Drug Resistance , Hedgehog Proteins , Humans , MicroRNAs/genetics , MicroRNAs/therapeutic use , Multiple Myeloma/drug therapy , Multiple Myeloma/genetics
5.
Hematology ; 26(1): 840-847, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34674612

ABSTRACT

OBJECTIVE: Acute myeloid leukemia (AML) is a form of primary acute leukemia with high mortality. Our previous study demonstrated that miR-149-3p was down-regulated in chemoresistant acute leukemia cells. However, the biological function of miR-149-3p in AML needs to be further explored. METHODS: Herein, the expression of miR-149-3p was overexpressed/silenced in U-937 human AML cells via transfection with miR-149-3p agomir/antagomir. The effect of miR-149-3p on U-937-induced tumor growth was investigated using a xenograft nude mouse model. RESULTS: The results showed that miR-149-3p overexpression inhibited the proliferation and increased the apoptosis of U-937 cells. In addition, miR-149-3p suppressed epithelial-mesenchymal transition in U-937 cells, as demonstrated by the miR-149-3p agomir-induced increase in E-cadherin expression and decrease in vimentin expression. The in vivo experiments demonstrated that miR-149-3p suppressed tumor progression. CONCLUSION: In conclusion, the findings revealed the association of miR-149-3p with the development of AML and suggest that miR-149-3p is a potential therapeutic candidate for AML.


Subject(s)
Epithelial-Mesenchymal Transition , Gene Expression Regulation, Neoplastic , Leukemia, Myeloid, Acute/genetics , MicroRNAs/genetics , Animals , Apoptosis , Cell Line, Tumor , Cell Proliferation , Female , Humans , Leukemia, Myeloid, Acute/pathology , Mice, Inbred BALB C , Mice, Nude
6.
Life Sci ; 257: 118057, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32634427

ABSTRACT

AIMS: We set about to investigate the potential role of microRNA-155-5p (miR-155-5p) in the development of immune thrombocytopenia (ITP), an idiopathic deficiency of blood platelets. MAIN METHODS: Initially, RT-qPCR and Western blot analyses were carried out to determine the expression of miR-155-5p and SOCS1 in peripheral blood mononuclear cells (PBMCs) and macrophages from ITP patients. We undertook gain- and loss- function methods by transfection of macrophages and PBMCs with treated plasmids. The expression patterns of platelet-related factors were measured by ELISA, and the expressions of PD1, PDL1, and macrophage M2 marker CD206 and CD86 were also measured. The relationship between miR-155-5p and SOCS1 was determined using the dual-luciferase reporter gene assay. We also established an ITP mouse model to explore the roles of miR-155-5p and SOCS1 in vivo. KEY FINDINGS: miR-155-5p was up-regulated, while SOCS1 was down-regulated in PBMCs and macrophages from ITP patients. SOCS1 was indicated as a target of miR-155-5p. Inhibition of miR-155-5p or up-regulation of SOCS1 facilitated macrophage M2 polarization as demonstrated by an increased M2/M1 ratio and suppressed expression of platelet-related factors. Furthermore, silencing of SOCS1 promoted ITP progression through blocking the PD1/PDL1 pathway, whilst upregulation of miR-155-5p remarkably increased the platelet abundance and suppressed SOCS1 expression in ITP model mice. SIGNIFICANCE: Silencing of miR-155-5p could promote PD1/PDL1 pathway-mediated macrophage M2 polarization and prevent ITP via up-regulation of SOCS1, thus relieving ITP.


Subject(s)
Macrophages/metabolism , MicroRNAs/genetics , Purpura, Thrombocytopenic, Idiopathic/genetics , Suppressor of Cytokine Signaling 1 Protein/genetics , Adult , Aged , Aged, 80 and over , Animals , B7-H1 Antigen/metabolism , Disease Progression , Down-Regulation , Female , Gene Silencing , Humans , Leukocytes, Mononuclear/metabolism , Male , Mice , Mice, Inbred CBA , Middle Aged , Programmed Cell Death 1 Receptor/metabolism , Purpura, Thrombocytopenic, Idiopathic/physiopathology , Up-Regulation , Young Adult
8.
Front Chem ; 8: 144, 2020.
Article in English | MEDLINE | ID: mdl-32195224

ABSTRACT

Incorporating fluorine (-F) substituents along the main-chains of polymer donors and acceptors is an effective strategy toward efficient bulk-heterojunction (BHJ) solar cells. Specifically, F-substituted polymers often exhibit planar conformations, leading to favorable packing, and electronic coupling. However, the effects of fluorine substituents on the charge generation and recombination characteristics that determine the overall efficiency of BHJ active layers remain critically important issues to examine. In this report, two PBDT[2X]T polymer analogs -poly[4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4, 5-b']dithiophene-thiophene] [PBDT[2H]T] and its F-substituted counterpart poly[4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b']dithiophene-3,4-difluoro-thiophene] [PBDT[2F]T]-are studied to systematically examine how -F substituents impact the blend morphology, charge generation, carrier recombination and extraction in BHJ solar cells. Considering the large efficiency differences between PBDT[2H]T- and PBDT[2F]T-based BHJ devices, significant emphasis is given to characterizing the out-of-plane morphology of the blend films as vertical phase-separation characteristics are known to have dramatic effects on charge transport and carrier extraction in polymer-fullerene BHJ solar cells. Herein, we use electron energy loss spectroscopy (EELS) in tandem with charge transport characterization to examine PBDT[2X]T-fullerene blend films. Our analyses show that PBDT[2H]T and PBDT[2F]T possess very different charge generation, recombination and extraction characteristics, resulting from distinct aggregation, and phase-distribution within the BHJ blend films.

9.
Sci Rep ; 9(1): 17192, 2019 Nov 20.
Article in English | MEDLINE | ID: mdl-31748587

ABSTRACT

Circular dichroism (CD) signals revealed in some materials may arise from different origins during measurements. Magnetic field dependent CD (MCD) emanating from the spin-polarized band provides direct insight into the spin-spin interband transitions in magnetic materials. On the contrary, natural CD effects which are artefactual signals resulting from the linear polarization (LP) components during the polarization modulation with a photo-elastic modulator in anisotropic polymer systems were usually observed. There is no simple method to reliably distinguish MCD effect due to spin polarized band structures from natural CD effect, which limits our understanding of the magnetic material/polymer hybrid structures. This paper aims to introduce a general strategy of averaging out the magnetic linear dichroism (MLD) contributions due to the anisotropic structure and disentangling MCD signal(s) from natural MCD signal(s). We demonstrate the effectiveness of separating MCD from natural MCD using rotational MCD measurement and presented the results of a sample with Co thin film on polymer Scotch tape (unplasticized polyvinyl chloride) glued on a quartz substrate. We demonstrate that the proposed method can be used as an effective tool in disentangling MCD and natural MCD effects, and it opens prospects to study the magnetic material /polymer hybrid systems.

10.
Ann Hepatol ; 17(5): 843-856, 2018 Aug 24.
Article in English | MEDLINE | ID: mdl-30145571

ABSTRACT

INTRODUCTION AND AIM: Developing reliable biomarkers for hepatocellular carcinoma (HCC) patients who are at a high risk of recurrence after curative hepatic resection is very important for determining subsequent therapeutic strategies. We investigated the role of the cell cycle factor NIMA-related kinase 2 (NEK2) in HCC progression in hepatoma cells and post-surgery patients. MATERIAL AND METHODS: The effects of NEK2 on proliferation, invasion and migration of hepatoma HuH7 and SK-Hep1 cells were evaluated. In a post-surgery HCC cohort (N = 97), the Nek2 induction levels in the tumors were examined with real-time RT-PCR analysis, and the results were analyzed for their correlations with recurrence. RESULTS: NEK2 promoted G1 to S phase cell cycle progression by causing increases in cyclin D1 and AKT phosphorylation and decreases in the cyclin-dependent kinase inhibitor p27, indicating that NEK2 plays an important role during interphase in addition to its previously identified role in M phase. NEK2 also enhanced the proliferation, migration and invasion of hepatoma cells and regulated the expression of E-cadherin and MMP9. The Nek2 mRNA levels in the tumors were highly correlated with recurrence rates in the post-surgery HCC patients. Combined evaluation of the tumor AJCC stage and the Nek2 level can serve as a reliable method for predicting the relative risk of HCC recurrence in these patients. CONCLUSIONS: NEK2 plays a significant role in cell cycle progression in the inter- and M-phases. NEK2 enhances HCC metastasis and is correlated with recurrence and thus can potentially serve a promising high-risk biomarker for HCC.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/surgery , Hepatectomy/adverse effects , Liver Neoplasms/surgery , NIMA-Related Kinases/metabolism , Neoplasm Recurrence, Local , Adult , Aged , Aged, 80 and over , Animals , Antigens, CD/metabolism , Biomarkers, Tumor/genetics , Cadherins/metabolism , Carcinoma, Hepatocellular/enzymology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/secondary , Cell Line, Tumor , Cell Movement , Cell Proliferation , Cyclin D1/metabolism , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Female , Humans , Liver Neoplasms/enzymology , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Male , Matrix Metalloproteinase 9/metabolism , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , NIMA-Related Kinases/genetics , Neoplasm Invasiveness , Neoplasm Staging , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Risk Factors , Signal Transduction , Time Factors , Treatment Outcome
11.
Sci Rep ; 8(1): 108, 2018 01 08.
Article in English | MEDLINE | ID: mdl-29311703

ABSTRACT

In this study, we integrated bilayer structure of covered Pt on nickel zinc ferrite (NZFO) and CoFe/Pt/NZFO tri-layer structure by pulsed laser deposition system for a spin Hall magnetoresistance (SMR) study. In the bilayer structure, the angular-dependent magnetoresistance (MR) results indicate that Pt/NZFO has a well-defined SMR behavior. Moreover, the spin Hall angle and the spin diffusion length, which were 0.0648 and 1.31 nm, respectively, can be fitted by changing the Pt thickness in the longitudinal SMR function. Particularly, the MR ratio of the bilayer structure (Pt/NZFO) has the highest changing ratio (about 0.135%), compared to the prototype structure Pt/Y3Fe5O12 (YIG) because the NZFO has higher magnetization. Meanwhile, the tri-layer samples (CoFe/Pt/NZFO) indicate that the MR behavior is related with CoFe thickness as revealed in angular-dependent MR measurement. Additionally, comparison between the tri-layer structure with Pt/NZFO and CoFe/Pt bilayer systems suggests that the SMR ratio can be enhanced by more than 70%, indicating that additional spin current should be injected into Pt layer.

12.
Health Qual Life Outcomes ; 15(1): 55, 2017 Mar 23.
Article in English | MEDLINE | ID: mdl-28330476

ABSTRACT

BACKGROUND: The leukemia affects not only the quality of life (QOL) of patients with the disease but also that of their family caregivers (FCs). The research studies on QOL of FCs for leukemia patients are limited. This study aimed to evaluate the QOL of FCs for leukemia patients in Heilongjiang province, China. METHODS: A cross-sectional questionnaire survey was undertaken with 309 FCs for leukemia patients recruited from three hospitals in Heilongjiang province. The QOL of the participants was assessed using the Chinese version of WHOQOL-BREF. Multivariate regression models were established to determine the predictors of the QOL of FCs, including the socio-economic characteristics of patients and FCs, and the emotional distress, social support and family functions of FCs. RESULTS: The FCs had low QOL scores in all four domains: 12.7 ± 2.8 for physical, 12.2 ± 2.5 for psychological, 13.2 ± 2.9 for social and 11.3 ± 2.5 for environment. Social support is a major predictor of the QOL of FCs, with a standardized ß coefficient of "high support" ranging from 0.41 to 0.58 for the four domains, followed by family function (ß = 0.37 ~ 0.44 for psychological, social and environmental domains). The FCs who were older, highly educated, had no religious belief, suffered from a higher level of emotional distress, and provided care to younger patients and the patients without insurance coverage had lower QOL than the others. CONCLUSION: The study provides some important insights into the QOL of FCs for leukemia patients. The QOL of FCs for leukemia patients is low and low levels of support to FCs are a major predictor of low QOL of FCs.


Subject(s)
Caregivers/psychology , Home Nursing/psychology , Leukemia/psychology , Palliative Care/psychology , Quality of Life/psychology , Adaptation, Psychological , Adult , Aged , China , Cross-Sectional Studies , Female , Humans , Leukemia/therapy , Male , Middle Aged , Social Support , Surveys and Questionnaires
13.
Mol Med Rep ; 13(1): 689-96, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26648539

ABSTRACT

Quercetin, a natural flavonoid, inhibits the growth of leukemia cells and induces apoptosis. Heat shock protein 27 (HSP27) has been reported to promote the development of leukemia by protecting tumor cells from apoptosis through various mechanisms. The present study investigated the effects of small hairpin (sh)RNA-mediated HSP27 knockdown on the anti­cancer effects of quercetin in U937 human leukemia cells. Cells were transfected with recombinant lentiviral vector pCMV­G­NR­U6­shHSP27 (shHSP27), which expressed shRNA specifically targeting the HSP27 gene, alone or in combination with quercetin. The results showed that shHSP27 and quercetin synergistically inhibited U937 cell proliferation and induced apoptosis by decreasing the Bcl2-to-Bax ratio. Furthermore, this combined treatment significantly suppressed the infiltration of tumor cells and the expression of angiogenesis­associated proteins HIF1α and VEGF. Compared with shHSP27 or quercetin alone, shHSP27 plus quercetin markedly decreased the protein expression of cyclinD1 and thus blocked the cell cycle at G1 phase. The Notch/AKT/mTOR signaling pathway is important in tumor aggressiveness; quercetin plus shHSP27 significantly decreased Notch 1 expression and the phosphorylation levels of the downstream signaling proteins AKT and mTOR. The inhibitory effects of quercetin plus shHSP27 on this pathway may thus have been responsible for the cell cycle arrest, inhibition of proliferations and infiltration as well as enhancement of apoptosis. Therefore, these findings collectively suggested that suppression of HSP27 expression amplified the anti­cancer effects of quercetin in U937 human leukemia cells, and that quercetin in combination with shHSP27 represents a promising therapeutic strategy for human leukemia.


Subject(s)
Antineoplastic Agents/pharmacology , HSP27 Heat-Shock Proteins/metabolism , Leukemia/pathology , Quercetin/pharmacology , Apoptosis/drug effects , Cell Adhesion/drug effects , Cell Proliferation/drug effects , G1 Phase/drug effects , Gene Knockdown Techniques , Heat-Shock Proteins , Humans , Molecular Chaperones , RNA, Small Interfering/metabolism , U937 Cells
14.
Biomed Res Int ; 2015: 678598, 2015.
Article in English | MEDLINE | ID: mdl-26290869

ABSTRACT

OBJECTIVE: This paper aimed to determine the standardised incidence ratio (SIR) of malignant pleural mesothelioma (MPM) in workers exposed to asbestos in Taiwan. METHODS: All workers employed in asbestos-related factories and registered by the Bureau of Labour Insurance between 1 March, 1950, and 31 December, 1989, were included in the study and were followed from 1 January, 1980, through 31 December, 2009. Incident cases of all cancers, including MPM (ICD-9 code: 163), were obtained from the Taiwan Cancer Registry. SIRs were calculated based on comparison with the incidence rate of the general population of Taiwan and adjusted for age, calendar period, sex, and duration of employment. RESULTS: The highest SIR of MPM was found for male workers first employed before 1979, with a time since first employment more than 30 years (SIR 4.52, 95% CI: 2.25-8.09). After consideration of duration of employment, the SIR for male MPM was 5.78 (95% CI: 1.19-16.89) for the workers employed for more than 20 years in asbestos-related factories. CONCLUSIONS: This study corroborates the association between occupational asbestos exposure and MPM. The highest risk of MPM was found among male asbestos workers employed before 1979 and working for more than 20 years in asbestos-related factories.


Subject(s)
Asbestos/toxicity , Lung Neoplasms/epidemiology , Mesothelioma/epidemiology , Occupational Exposure/adverse effects , Pleural Neoplasms/epidemiology , Adult , Aged , Female , Humans , Incidence , Lung Neoplasms/chemically induced , Male , Mesothelioma/chemically induced , Mesothelioma, Malignant , Middle Aged , Pleural Neoplasms/chemically induced , Retrospective Studies , Taiwan
15.
J Pathol ; 236(3): 337-47, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25775999

ABSTRACT

Although hepatitis B virus (HBV) has been established to cause hepatocellular carcinoma (HCC), the exact mechanism remains to be clarified. Type II ground glass hepatocytes (GGHs) harbouring the HBV pre-S2 mutant large surface protein (LHBS) have been recognized as a morphologically distinct hallmark of HCC in the advanced stages of chronic HBV infection. Considering its preneoplastic nature, we hypothesized that type II GGH may exhibit high genomic instability, which is important for the carcinogenic process in chronic HBV carriers. In this study we found that pre-S2 mutant LHBS directly interacted with importin α1, the key factor that recognizes cargos undergoing nuclear transportation mediated by the importin α/ß-associated nuclear pore complex (NPC). By interacting with importin α1, which inhibits its function as an NPC factor, pre-S2 mutant LHBS blocked nuclear transport of an essential DNA repair and recombination factor, Nijmegen breakage syndrome 1 (NBS1), upon DNA damage, thereby delaying the formation of nuclear foci at the sites of DNA double-strand breaks (DSBs). Pre-S2 mutant LHBS was also found to block NBS1-mediated homologous recombination repair and induce multi-nucleation of cells. In addition, pre-S2 mutant LHBS transgenic mice showed genomic instability, indicated by increased global gene copy number variations (CNVs), which were significantly higher than those in hepatitis B virus X mice, indicating that pre-S2 mutant LHBS is the major viral oncoprotein inducing genomic instability in HBV-infected hepatocytes. Consistently, the human type II GGHs in HCC patients exhibited increased DNA DSBs representing significant genomic instability. In conclusion, type II GGHs harbouring HBV pre-S2 mutant oncoprotein represent a high-risk marker for the loss of genome integrity in chronic HBV carriers and explain the complex chromosome changes in HCCs. Mouse array CGH raw data: GEO Accession No. GSE61378 (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE61378).


Subject(s)
Carcinoma, Hepatocellular/genetics , Cell Transformation, Viral/genetics , Hepatitis B Surface Antigens/genetics , Hepatitis B virus/genetics , Hepatitis B, Chronic/genetics , Liver Neoplasms/genetics , Protein Precursors/genetics , Animals , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/virology , Cell Line, Tumor , Comparative Genomic Hybridization , DNA Breaks, Double-Stranded , DNA Copy Number Variations , DNA Damage , DNA Repair , Female , Genomic Instability , Hepatitis B Surface Antigens/metabolism , Hepatitis B virus/metabolism , Hepatitis B, Chronic/metabolism , Hepatitis B, Chronic/pathology , Hepatitis B, Chronic/virology , Hepatocytes/metabolism , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/virology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mutation , Protein Precursors/metabolism , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism
16.
J Agric Food Chem ; 63(1): 192-9, 2015 Jan 14.
Article in English | MEDLINE | ID: mdl-25525886

ABSTRACT

Monascus-fermented products have been used as dietary food and traditional medicine due to their beneficial effects on circulation and digestive systems in Asia for thousands of years. Besides, monascin and ankaflavin, secondary metabolites from Monascus-fermented products, have proven anti-inflammatory and immunomodulatory effects. In previous research, monascin and ankaflavin ameliorated ovalbumin-induced airway allergic reaction often used as a type I allergy asthma model. Additionally, mast cells play critical roles in type I allergy. Therefore, RBL-2H3 cells were used as the mast cell model to determine whether the improving effects on asthma of monascin and ankaflavin came from influencing mast cells. PMA and ionomycin are common activators of mast cells because they stimulate the main signaling molecules during mast cell activation. Forty micromolar monascin and ankaflavin inhibited PMA/ionomycin-induced mast cell degranulation and TNF-α secretion through suppressing the phosphorylation of PKC and MAPK family ERK, JNK, and p38. Consequently, monascin and ankaflavin affected the activation of mast cells and may have the potential to improve type I allergy.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Flavins/pharmacology , Heterocyclic Compounds, 3-Ring/pharmacology , Mast Cells/drug effects , Monascus/metabolism , Animals , Anti-Inflammatory Agents/metabolism , Asthma/drug therapy , Asthma/immunology , Cell Line , Fermentation , Flavins/metabolism , Heterocyclic Compounds, 3-Ring/metabolism , Humans , Mast Cells/immunology , Monascus/chemistry , Oryza/metabolism , Oryza/microbiology , Rats , Secondary Metabolism
17.
Int J Clin Exp Pathol ; 8(11): 15489-96, 2015.
Article in English | MEDLINE | ID: mdl-26823919

ABSTRACT

WISP1, a Wnt-induced secreted protein, has been found to have anticancer activity. ALL is a leading cause of death. Here we investigate the WISP1 effects on ALL Jurkat cells. Cell viability was assessed by CCK-8. Cell cycle and apoptosis were detected by flow cytometry. Mitochondrial membrane potential (MMP) was monitored using TMRM. Generation of reactive oxygen species (ROS) was quantified using DCFH-DA. Western blot was used to detect the expression of cell proliferation and apoptosis related genes. The results showed that knockdown of WISP1 significantly inhibited proliferation of Jurkat cells. Parallelly, cell cycle distribution was increased at G1 phase and apoptotic rate was induced after WISP1 knockdown. Furthermore, knockdown of WISP1 induced apoptosis of Jurkat cells was also associated with loss of MMP and generation of ROS. Western blot results showed that the protein expression p-AKT, PCNA, CDK1, P-ERK, CDK2, VEGF, VEGFR2 and Bcl2 were decreased, while the expression of Bax was up-regulated. In conclusion, WISP1 plays an important role in proliferation and apoptosis of Jurkat cells in mitochondria dependent pathway, the specific mechanisms need further study.


Subject(s)
Apoptosis , CCN Intercellular Signaling Proteins/metabolism , Cell Proliferation , Gene Knockdown Techniques , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Proto-Oncogene Proteins/metabolism , Apoptosis Regulatory Proteins/metabolism , CCN Intercellular Signaling Proteins/genetics , Cell Cycle Proteins/metabolism , Down-Regulation , G1 Phase Cell Cycle Checkpoints , Gene Expression Regulation, Neoplastic , Humans , Jurkat Cells , K562 Cells , Membrane Potential, Mitochondrial , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Proto-Oncogene Proteins/genetics , RNA Interference , Reactive Oxygen Species/metabolism , Signal Transduction , Time Factors , Transfection , U937 Cells
18.
Int Ophthalmol ; 34(4): 971-7, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24488041

ABSTRACT

The aim of this study was to report the successful treatment of choroidal neovascularization (CNV) in pathologic myopia (PM) with a posterior sub-Tenon bevacizumab (PSTB; Avastin(®)) injection. The study was a prospective case series including nine eyes of eight patients with PM and CNV. All nine eyes were injected with PSTB (12.5 mg/0.5 ml). Treatment effectiveness was evaluated with optical coherence tomography (OCT). If intraretinal edema or subretinal fluid were detected, injections were repeated after 2 weeks. The main outcome measures were logMAR best-corrected visual acuity (BCVA) and central foveal thickness. The mean follow-up time was 77.56 weeks. BCVA improved by a mean of -0.38 logMAR (>3 lines). The average reduction in absolute central foveal thickness was 25.67 µm. OCT revealed marked CNV volume reduction and fluid-free status in seven eyes. The fluid-free status remained for ≥ 1 year in these eyes. Fluorescein angiography revealed CNV resolution in three eyes. Corneal stromal penetration of subconjunctival bevacizumab has been demonstrated in animal studies. PSTB may be an equally effective, yet less invasive alternative for the treatment of myopic CNV.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Antibodies, Monoclonal, Humanized/administration & dosage , Choroidal Neovascularization/drug therapy , Myopia/complications , Adult , Aged , Bevacizumab , Choroidal Neovascularization/complications , Female , Follow-Up Studies , Humans , Injections, Intraocular , Middle Aged , Prospective Studies , Visual Acuity , Young Adult
19.
Clin Lab ; 59(7-8): 735-40, 2013.
Article in English | MEDLINE | ID: mdl-24133900

ABSTRACT

BACKGROUND: The study was conducted in order to analyze the incidence of heparin-induced thrombocytopenia (HIT) and heparin-induced thrombocytopenia and thrombosis syndrome (HITTS) in 240 patients from the Department of Vascular Surgery in China, to evaluate the current laboratory detection technique, and to explore the feasibility for the technique to be developed in China. METHODS: 240 patients receiving unfractionated heparin (UFH) were studied in one center. Before and after the UFH treatment, platelet count, HIT-antibody ELISA test, and heparin-induced platelet aggregation (HIPA) were tested. RESULTS: Among 240 patients, HIT was diagnosed in 36 cases. The incidence was 15%. HITTS occurred in 6 cases (2.5%). The median time of thrombocytopenia was the 8th day. Platelet counts recovered to normal level in 3 - 6 days after heparin withdrawal CONCLUSIONS: The incidence of HIT is higher; however, the incidence of HITTS is lower. Monitoring platelet count, which is simple and easy to do and available in hospitals at different levels (township hospital included), is a reliable method to diagnose HIT early. The HIT-antibody ELISA test could be introduced in specific hospitals to prescreen HIT. In view of the higher sensitivity and specificity of HIPA, it can be used in larger diagnostic centers in all the big cities of China.


Subject(s)
Heparin/adverse effects , Thrombocytopenia/chemically induced , Adult , Aged , China , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Platelet Activation
20.
J Virol ; 87(23): 12675-84, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24049181

ABSTRACT

Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC) worldwide. The pre-S2 mutant large HBV surface protein (Δ2 LHBS), which contains an in-frame deletion of approximately 17 amino acids in LHBS, is highly associated with risks and prognoses of HBV-induced HCC. It was previously reported that Δ2 LHBS interacts with the Jun activation domain-binding protein 1 (JAB1), a zinc metalloprotease. This promotes the degradation of the cell cycle regulator p27(Kip1) and is believed to be the major mechanism for Δ2 LHBS-induced HCC. In this study, it was found that the interaction between JAB1 and Δ2 LHBS is facilitated by divalent metal Zn(2+) ions. The binding of JAB1 to Δ2 LHBS requires the JAB1/CSN5 MPN metalloenzyme (JAMM) motif and residue H138 that binds to Zn(2+) ions in JAB1. Isothermal titration calorimetry showed that Δ2 LHBS binds directly to Zn(2+) ions in a two-site binding mode. Residues H71 and H116 in Δ2 LHBS, which also contact Zn(2+) ions, are also indispensable for Δ2 LHBS-mediated p27(Kip1) degradation in human HuH7 cells. These results suggest that developing drugs that interrupt interactions between Δ2 LHBS and JAB1 can be used to mitigate Δ2 LHBS-associated risks for HCC.


Subject(s)
Carcinoma, Hepatocellular/enzymology , Hepatitis B Surface Antigens/metabolism , Hepatitis B virus/metabolism , Hepatitis B, Chronic/enzymology , Intracellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/enzymology , Peptide Hydrolases/metabolism , Protein Precursors/metabolism , Zinc/metabolism , Amino Acid Motifs , COP9 Signalosome Complex , Carcinoma, Hepatocellular/virology , Cell Line, Tumor , Hepatitis B Surface Antigens/genetics , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Humans , Intracellular Signaling Peptides and Proteins/chemistry , Intracellular Signaling Peptides and Proteins/genetics , Liver Neoplasms/virology , Peptide Hydrolases/chemistry , Peptide Hydrolases/genetics , Protein Binding , Protein Precursors/genetics
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