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Background: Pulmonary arterial hypertension (PAH) is a worldwide challenging disease characterized by progressive elevation of pulmonary artery pressure. The proliferation, migration and phenotypic transformation of pulmonary smooth muscle cells are the key steps of pulmonary vascular remodeling. Quercetin (3,3', 4', 5, 6-pentahydroxyflavone, Que) is a natural flavonol compound that has antioxidant, anti-inflammatory, anti-tumor and other biological activities. Studies have shown that Que has therapeutic effects on PAH. However, the effect of quercetin on pulmonary vascular remodeling in PAH and its mechanism remain unclear. Methods and results: In vivo, PAH rats were constructed by intraperitoneal injection of monocrotaline (MCT) at 60 mg/kg. Human pulmonary artery smooth muscle cells (HPASMCs) were treated with platelet-derived growth factor BB (PDGF-BB) 20 ng/mL to construct PAH cell model in vitro. The results showed that in vivo studies, MCT could induce right ventricular wall hyperplasia, narrow the small and medium pulmonary artery cavity, up-regulate the expression of proliferating and migration-related proteins proliferating cell nuclear antigen (PCNA) and osteopontin (OPN), and down-regulate the expression of alpha-smooth muscle actin (α-SMA). Que reversed the MCT-induced results. This process works by down-regulating the transforming growth factor-β1 (TGF-β1)/ Smad2/3 signaling pathway. In vitro studies, Que had the same effect on PDGF-BB-induced proliferation and migration cell models. Conclusions: Que inhibits the proliferation, migration and phenotypic transformation of HPASMCs by down-regulating TGF-β1/Smad2/Smad3 pathway, thereby reducing right ventricular hyperplasia (RVH) and pulmonary vascular remodeling, providing potential pharmacological and molecular explanations for the treatment of PAH. Highlights: (1) Que can significantly improve the hemodynamic changes, RVH and pulmonary vascular remodeling in MCT induced PAH rats. (2) Que inhibits the proliferation, migration and phenotypic transformation of HPASMCs by regulating TGF-β1/Smad2/Smad3 pathway, thus playing a protective role in PAH pulmonary vascular remodeling. [ABSTRACT FROM AUTHOR]

Ticks can carry multiple pathogens, and Inner Mongolia’s animal husbandry provides excellent environmental conditions for ticks. This study characterized the microbiome of ticks from different geographical locations in Inner Mongolia; 905 Dermacentor nuttalli and 36 Ixodes persulcatus were collected from sheep in three main pasture areas and from bushes within the forested area. Mixed DNA samples were prepared from three specimens from each region and tick species. Microbial diversity was analyzed by 16S rRNA sequencing, and α and β diversity were determined. The predominant bacterial genera were Rickettsia (54.60%), including Rickettsiales bacterium Ac37b (19.33%) and other Rickettsia (35.27%), Arsenophonus (11.21%), Candidatus Lariskella (10.84%), and Acinetobacter (7.17%). Rickettsia bellii was identified in I. persulcatus, while Rickettsiales bacterium Ac37b was found in D. nuttalli from Ordos and Chifeng. Potential Rickettsia and Anaplasma coinfections were observed in the Ordos region. Tick microbial diversity analysis in Inner Mongolia suggests that sheep at the sampling sites were exposed to multiple pathogens.

Objective: To investigate whether probenecid (PROB) could improve the proliferation and migration ability of rats' pulmonary artery smooth muscle cells induced by platelet-derived growth factor-BB (PDGF-BB)., Methods: Primary pulmonary artery smooth muscle cells (PASMCs) of SD rats were cultured in vitro , and were randomly divided into control group (CON group), PDGF-BB group (10 ng/ml PDGF-BB treatment for 24 h) and PDGF-BB+PROB group (10 ng/ml PDGF-BB and 200 μmol/L PROB treatment for 24 h, PROB is a specific blocker of pannexin-1). CCK-8 method was used to select the suitable intervention concentrations of PROB and PDGF-BB, and to detect the proliferation of PASMCs in each group. The migration ability of PASMCs was detected by Transwell TM assay and cell scratch test. Immunofluorescence cytochemistry and Western blot were used to detect the protein expressions and distribution of osteopontin (OPN) and proliferating cell nuclear antigen (PCNA) in PASMCs., Results: Compared with CON group, the migration and proliferation ability of PASMCs in PDGF-BB group were enhanced ( P ＜0.05). After treated with PROB, the migration and proliferation ability of PASMCs in PDGF-BB+PROB group were decreased significantly ( P ＜0.05). Compared with CON group, the expression and protein levels of OPN and PCNA in PDGF-BB group were increased significantly ( P ＜0.05), while the expression and protein levels of OPN and PCNA in PDGF-BB+PROB were decreased significantly ( P ＜0.05)., Conclusion: Probenecid inhibits the migration and proliferation of PDGF-BB-induced PASMCs by blocking Pannexin-1.

This study is to optimize the preparation process of fusion protein Fv-LDP which was expressed in the form of inclusion body and consisted of lidamycin apoprotein LDP and single-chain Fv antibody (scFv) directed against type IV collagenase. The preparation and the dissolution of inclusion body, the immobilized metal affinity chromatography of the target protein and the renaturization by stepwise dialysis were optimized by single-factor analysis or orthogonal design. In addition, the refolded fusion protein Fv-LDP was refined by Sephadex G-75 chromatography followed by fluorescence-activated cell sorter (FACS)-based saturation binding assay to measure its antigen-binding activity. After optimization of the process, the purity of fusion protein Fv-LDP existed in the inclusion body was 63.9% and the corresponding solubility was 95.7%; Under denaturing conditions, the purity of fusion protein Fv-LDP was more than 95% after the purification process. The percentage of monomeric fusion protein Fv-LDP was 60% after the refolding process, while it was further refined to 85% which was 5.6-fold higher than that of the initial refolding condition. The refined fusion protein Fv-LDP could bind to human lung adenocarcinoma PAa cells and human hepatoma BEL-7402 cells with the dissociation constants (Kd) of 0.176 micromol x L(-1) and 0.904 micromol x L(-1), respectively. The preparation process of fusion protein Fv-LDP has been successfully optimized, which provides the experimental basis for the production and future development of fusion protein Fv-LDP, and might serve as a relatively practical system for the preparation of other scFv-based proteins expressed in the form of inclusion body.

This study is to investigate the binding capability of lidamycin apoprotein (LDP), an enediyne-associated apoprotein of the chromoprotein antitumor antibiotic family, to human breast cancer and normal tissues, the correlation of LDP binding capability to human breast cancer tissues and the expression of tumor therapeutic targets such as VEGF and HER2. In this study, the binding capability of LDP to human breast cancer tissues was detected with tissue microarray. The correlation study of LDP binding capability to human breast tumor tissues and relevant therapeutic targets was performed on breast cancer tissue microarrays. Immunocytochemical examination was used to detect the binding capability of LDP to human breast carcinoma MCF-7 cells. As a result, tissue microarray showed that LDP staining of 73.2% (30/41) of breast cancer tissues was positive, whereas that of 48.3% (15/31) of the adjacent normal breast specimens was positive. The difference between the tumor and normal samples was significant (Chi2 = 4.63, P < 0.05). LDP immunoreactivity in breast cancer correlated significantly with the overexpression of VEGF and HER2 (P < 0.001 and < 0.01, r = 0.389 and 0.287, respectively). Determined with confocal immunofluorescent analysis, LDP showed the binding capability to mammary carcinoma MCF-7 cells. It is demonstrated that LDP can bind to human breast cancer tissues and there is significant difference between the breast cancer tissues and the corresponding normal tissues. Notably, the binding reactivity shows positive correlation with the expression of VEGF and HER2 in breast carcinoma tissues. The results imply that LDP may have a potential use as targeting drug carrier in the research and development of new anticancer therapeutics. This study may provide reference for drug combination of LDM and other therapeutic agents.

Objective: To study the effect of co-blockage of vascular endothelial growth factor (VEGF) and its receptor (KDR) on growth of bladder carcinoma T24 cells and nude mice xenograft., Methods: T24 cell line co-transfected with VEGF siRNA and sKDR expression plasmids was developed and its proliferation was assayed by MTT and apoptosis by FCM. The nude mice model bearing bladder carcinoma xenograft was established. The tumor cell VEGF expression, stroma microvessel density (MVD) and tumor cell topoisomerase II alpha (Topo II alpha) expression were detected by immunohistochemistry. Cell apoptosis was estimated by TUNEL assay., Results: MTT assay showed that cell proliferation in VEGF siRNA, sKDR and combination groups was 56.3% +/- 8.3%, 42.6% +/- 13.8% and 32.5% +/- 4.3%, respectively, significantly lower than that in the scramble control (97.3% +/- 11.6%, P < 0.0001). FCM showed there were sub-diploid apoptotic peaks before G1 phase in VEGF siRNA, sKDR and combination groups, and apoptosis ratio was 5.1% +/- 0.9%, 4.2% +/- 0.5% and 8.8% +/- 0.7%, respectively, all of which were higher than that in the scramble control (0.9% +/- 0.4%, P < 0.05), and the combination group had even more higher apoptosis than the two singlely treated groups (P < 0.01). In vivo test showed that tumor growth was inhibited in VEGF siRNA, sKDR and combination groups, and from day 16 the tumor volume in combination group was significantly smaller than that in scramble control (P < 0.05), and from day 28 the tumor almost lost the ability to further growth. Immunohistochemistry revealed VEGF expression in combination group was 54.37 +/- 5.28, significantly lower than that in the scramble control (141.66 +/- 8.59, P < 0.0001). MVD number was only 8.22 +/- 3.79, much less compared with that in the scramble control (61.76 +/- 5.28, P < 0.0001) or sKDR group (19.46 +/- 4.16, P = 0.0089). Tumor cell proliferation index in the combination group (1.5% +/- 0.7%) was significantly decreased compared with that in the scramble control (11.8% +/- 5.2%, P < 0.0001), and apoptosis index (67.2% +/- 8.5%) was much higher than that in the scramble control (8.7% +/- 2.7%, P < 0.0001), VEGF siRNA group (54.3% +/- 4.8%, P = 0.0492) or sKDR group (52.3% +/- 6.4%, P = 0.0293)., Conclusion: VEGF siRNA or sKDR alone can inhibit tumor cell proliferation and induce cell apoptosis, but co-blockage of VEGF and KDR by their combination shows more significant therapeutic efficacy.

Objective: To investigate the effect of lidamycin (LDM) on telomerase activity in human hepatoma BEL-7402 cells under the condition of LDM inducing mitotic cell death and senescence., Methods: Chromatin condensation was detected by co-staining with Hoechst 33342 and PI. Cell multinucleation was observed by Giemsa staining and genomic DNA was separated by agarose gel electrophoresis. Fluorescent intensity of Rho123 was determined for mitochondrial membrane potential. MTT assay and SA-beta-gal staining were employed to analyze the senescence-like phenotype. The expression of proteins was analyzed by Western blot. Telomerase activity was assayed by telomerase PCR-ELISA., Results: Mitotic cell death occurred in LDM-treated cells characterized by unique and atypical chromatin condensation, multinucleation and increased mitochondrial membrane potential. However, no apoptotic bodies or DNA ladders were found. In addition, apoptosis-related proteins remained nearly unaltered. Senescence-like phenotype was identified by increased and elongated size of cells, growth retardation, enhanced SA-beta-gal activity and the changes of senescence-related protein expression. Telomerase activity markedly decreased (P<0.01) in LDM-treated hepatoma BEL-7402 cells., Conclusion: Mitotic cell death and senescence could be triggered simultaneously or sequentially after exposure of hepatoma BEL-7402 cells to LDM. The decrease in telomerase activity may play a key role in the defective mitosis and aging morphology. Further investigation of detailed mechanism is needed.