[Exploration for and Practice of New-Model Undergraduate Education for Innovative Talents in Biomedicine].

With the rapid development of modern biomedical technology industry, background and knowledge of a single discipline will not be adequate to meet the needs of research and development of cutting-edge technology. The cultivation of innovative research talents with interdisciplinary background at the undergraduate level poses great challenges for higher education institutions. National-level research institutes, including state key laboratories and national clinical research centers, for example, have an enormous supply of technological human resources and resources for research and teaching, which is of critical importance for the training of innovative talents at the undergraduate level. Herein, taking as an example the West China Innovation Class of State Key Laboratory of Biotherapy, a special undergraduate program founded by the State Key Laboratory of Biotherapy, Sichuan University in 2016, we reported on the explorations and practices of a new model for cultivating innovative research talents at the undergraduate level. The new model features the leadership of a national-level research institute and an interdisciplinary approach.

Metformin prevents against oxidative stress-induced senescence in human periodontal ligament cells.

Periodontitis is a chronic infectious disease involving periodontal tissues. Periodontal ligament cells (PDLCs) play an important role in the regeneration of periodontal tissue. However, senescent PDLCs have an impeded regenerative potential. Metformin has been reported to prevent senescence at both the cellular and individual levels. The objectives of the present study were to evaluate the effects of metformin on cellular senescence in human PDLCs (hPDLCs) under oxidative stress. hPDLCs were pretreated with metformin, followed by H2O2 exposure. The cell viability, oxidative damage, cellular senescence and osteogenic potential were detected. To inhibit autophagy, hPDLCs were treated with 3-methyladenine before metformin treatment. The present study revealed that H2O2 exposure inhibits proliferation, increased lysosomal ß-galactosidase activity, augments reactive oxidative species (ROS) accumulation, elevates the oxidative damage, stimulates the expression of senescence-related genes and impedes the activity of the osteogenic differentiation of hPDLCs. Metformin pretreatment could partly reverse the detrimental influences of H2O2 on hPDLCs. Moreover, metformin could stimulate autophagy, whereas the inhibition of autophagy with 3-methyladenine reversed the anti-senescence effects of metformin on hPDLCs under oxidative stress. The present study manifested that metformin could alleviate oxidative stress-induced senescence via stimulating autophagy and could partially recover the osteogenic potential of hPDLCs, possibly providing a reference for the discovery of periodontal treatment from the perspective of antisenescence.

Effect of metformin on human periodontal ligament stem cells cultured with polydopamine-templated hydroxyapatite.

Polydopamine-templated hydroxyapatite (tHA) is a type of nano-biomaterial that can promote osteogenesis in bone tissue engineering. However, high concentrations of tHA stimulate production of reactive oxygen species (ROS), resulting in cell injury and apoptosis. Metformin has been demonstrated to activate the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, which induces autophagy and decreases ROS production to prevent apoptosis. The present study was performed to investigate the potential application of tHA in combination with metformin in periodontal bone tissue engineering. Human periodontal ligament stem cells (hPDLSCs) were exposed to tHA in the presence or absence of metformin, and cytocompatibility and osteogenesis were detected by related assays. Additionally, the autophagy signaling pathway was analyzed by western blotting. Polydopamine-templated hydroxyapatite, in combination with metformin, substantially reduced ROS production and apoptosis, and enhanced proliferation and osteogenic differentiation of hPDLSCs. Enhanced levels of microtubule-associated protein 1 light chain 3 II and Beclin-1 were observed after exposure to tHA plus metformin. Expression of phosphorylated AMPK was increased and that of phosphorylated mammalian target of rapamycin (mTOR) was decreased after exposure to tHA plus metformin. Taken together, our results demonstrate that tHA, combined with metformin, increases the viability of hPDLSCs via the AMPK/mTOR signaling pathway by regulating autophagy and further improving the osteogenic effect.

Secondhand smoke is associated with heavy metal concentrations in children.

Secondhand smoke (SHS) has adverse effects on health, particularly for children. Our purpose was to analyze the correlation between SHS exposure and heavy metal concentrations in children. The investigation was conducted in Xinxiang County, Henan Province, China, from August 2015 to December 2015. In total, 821 students (433 boys and 388 girls) were recruited, and the contents of heavy metals in their hair-including chromium, manganese, nickel, arsenic, lead, and cadmium-were detected by ICP-MS. The children's parents were informed, and a questionnaire was conducted, which included questions about smoking habits and demographic characteristics. Our results indicate that all parent smokers are fathers, 48.9% of fathers who are smokers, but 25.2% of fathers smoke in front of their children. The levels of chromium (median girls vs boys, µg/g) (2.36 vs 2.06, p < 0.001), nickel (1.28 vs 0.97, p < 0.001), arsenic (0.55 vs 0.49, p < 0.001), and lead (2.73 vs 2.16, p < 0.001) in girls were significantly higher than in boys. The levels of cadmium (median, SHS group vs control: 0.43 vs 0.29 (µg/g), p < 0.001) and lead (median, SHS group vs control: 2.71 vs 2.27 (µg/g), p = 0.007) in the SHS group were significantly higher than in the control. Multi-linear regression analysis indicated that SHS exposure in children is very likely to be correlated with increasing levels of lead (ß (95% CI): 0.53 (0.99-5.14), p = 0.023) and cadmium (ß (95% CI): 0.43 (0.14-0.73), p = 0.003) in their hair. In conclusion, children exposed to SHS have increased lead and cadmium accumulations in the body. CONCLUSION: In our study, 821 students (433 boys and 388 girls) were recruited, and the contents of heavy metals in their hair-including chromium, manganese, nickel, arsenic, lead, and cadmium-were detected by ICP-MS. And the secondhand smoking (SHS) exposure was inquired by face-to-face investigation of their parents. We illustrated that children exposed to SHS have increased lead and cadmium accumulations in the body. What is Known: • Secondhand smoke (SHS) has adverse effects on health, particularly for children. • There might be correlation between SHS exposure and heavy metal concentrations in children. What is New: • The levels of chromium, nickel, arsenic, and lead in girls were significantly higher than in boys. • SHS exposure in children was correlated with increasing levels of lead and cadmium in their hair because of exposure to SHS.

Simultaneous removal of nitrogen and phosphorus by cetylpyridinium bromide modified zeolite.

In this study, surfactant modified zeolite-clinoptilolite (SMZ) by CPB (cetylpyridinium bromide) was used for simultaneous removal of ammonium, nitrate and phosphate in synthetic wastewater, and the sorption properties of SMZ were determined and compared with natural zeolite. Results showed that natural clinoptilolite had good affinity for ammonium (8.940 mg/g), but not for nitrate (0.427 mg/g) and phosphate (0.801 mg/g). With the increase of surfactant loading from 5 g/L to 40 g/L, the sorption capacity for nitrate increased from 0.462 mg/g to 4.661 mg/g. when the surfactant loading is 40 g/L, the SMZ has a phosphate adsorption capacity of 2.119 mg/g. The SMZ had a significant enhancement on nitrate and phosphate sorption, could simultaneously remove ammonium, nitrate and phosphate at specific conditions, with removal efficiency up to 85.2%, 83.1% and 56.7%, respectively. Orthogonal experiments showed that ammonium concentration was the most important factor for ammonium sorption on SMZ. Surfactant loading was the major factor for nitrate and phosphate sorption. With the increase of surfactant loading from 5 g/L to 40 g/L, the sorption capacity for nitrate increased from 0.462 mg/g to 4.661 mg/g. When the surfactant loading is 40 g/L, the SMZ has the best phosphate adsorption capacity 2.119 mg/g. Samples were characterized by X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). Semi-empirical quantum mechanics molecular simulation indicated that electrostatic attraction existed between CPB and dihydrogen phosphate ion. Results indicate that SMZs might have great potential of removing cations and anions simultaneously in the aquatic environment, which is good for eutrophication control and nutrients removal.

Expression of Th17 and CD4+ CD25+ T regulatory cells in peripheral blood of acute leukemia patients and their prognostic significance.

To discuss the expression of T helper cell 17 (Th17) cells and CD4+ CD25+ Foxp3+ regulatory T cells (Treg) in peripheral blood (PB) of patients with acute leukemia (AL), and to explore the relationship between them and disease prognosis. 40 patients diagnosed with acute leukemia in The First Affiliated Hospital of Zhengzhou University from July 2012 to August 2014 were selected as the observation group. Meanwhile, 40 healthy people were taken as the control group. Flow Cytometry Method (FCM) was used to detect the level of Th17 cells and CD4+ CD25+ Foxp3+ cells in peripheral blood of the two groups, and enzyme-linked immuno sorbent assay (ELISA) method was used to test the level of IL17 and TGF-ß in peripheral blood of two groups; reverse transcription-polymerase chain reaction (RT-PCR) was adopted to analyze the mRNA levels of RORγT and Foxp3 in peripheral blood. In addition, we examined the levels of Th17 and CD4+ CD25+ Foxp3+ cells and associated factor levels in patients with remission after AL chemotherapy. the Th17 cells (CD3+ CD4+ IL-17+) in acute leukemia patients accounted for (1.51±0.27)%, which was significantly higher than that of control group (0.36±0.23)%, with statistical significance (t=20.51, P<0.001); the percentage of CD4+ CD25+ Foxp3+ cells in AL patients was (3.37±0.48)%, which was significantly higher than that of control group of (1.26±0.27)%, with statistical significance (t=24.23, P<0.001); the serum levels of IL-17 and TGF-ß in AL patients were (28.12±6.33) pg/ml and (38.41±8.44) pg/ml respectively, which were all significantly higher than that of control group of (14.41±6.21) pg/ml and (24.49±7.42) pg/ml, with statistical significance (t=7.83, P<0.001; t=7.83, P<0.001); the RORγT mRNA and Foxp3 mRNA levels in AL patients were all significantly higher than that of control group, with statistical significance (t=12.27, P<0.001; t=7.89, P<0.001). In addition, compared with before chemotherapy, the levels of Th17 cells and CD4+ CD25+ Foxp3+ cells, and the serum levels of IL-17 and TGF-ß in acute leukemia patients all decreased significantly after 6 months of chemotherapy, and the difference was statistically significant (P<0.001). Th17 cells, CD4+ CD25+ Foxp3+ cells and their secretory proteins IL-17, TGF-ß and transcription factors were significantly increased in AL patients. Therefore, regular detection of peripheral blood Th17 and Treg cells, as well as their secretory proteins are useful for monitoring the immune status and prognosis of patients.

Virtual screening in small molecule discovery for epigenetic targets.

Epigenetic modifications are critical mechanisms that regulate many biological processes and establish normal cellular phenotypes. Aberrant epigenetic modifications are frequently linked to the development and maintenance of several diseases including cancer, inflammation and metabolic diseases and so on. The key proteins that mediate epigenetic modifications have been thus recognized as potential therapeutic targets for these diseases. Consequently, discovery of small molecule inhibitors for epigenetic targets has received considerable attention in recent years. Here, virtual screening methods and their applications in the discovery of epigenetic target inhibitors are the focus of this review. Newly emerging approaches or strategies including rescoring methods, docking pose filtering methods, machine learning methods and 3D molecular similarity methods were also underlined. They are expected to be employed for identifying novel inhibitors targeting epigenetic regulation more efficiently.

Causes and nursing countermeasures in pediatric PICC catheter complications.

To analyze the complications and nursing countermeasures of PICC (Peripherally Inserted Central Catheter) catheters using children PICC catheter technique 40 cases, complications were observed, and analyze the original causes, in order to propose a solution. There were 10 cases of catheter blockage, 5 cases of catheter infection, 6 cases of phlebitis, 5 cases of puncture difficulties, 2 cases of poor feeding tube, 2 cases of bleeding puncture site with the continuous exploration and research of nursing intervention, the production of clinical complications from PICC has been used in children were greatly reduced.

Expression of Th17 and CD4+ CD25+ T regulatory cells in peripheral blood of acute leukemia patients and their prognostic significance.

To discuss the expression of T helper cell 17 (Th17) cells and CD4+ CD25+ Foxp3+ regulatory T cells (Treg) in peripheral blood (PB) of patients with acute leukemia (AL), and to explore the relationship between them and disease prognosis. 40 patients diagnosed with acute leukemia in The First Affiliated Hospital of Zhengzhou University from July 2012 to August 2014 were selected as the observation group. Meanwhile, 40 healthy people were taken as the control group. Flow Cytometry Method (FCM) was used to detect the level of Th17 cells and CD4+ CD25+ Foxp3+ cells in peripheral blood of the two groups, and enzyme-linked immuno sorbent assay (ELISA) method was used to test the level of IL17 and TGF-ß in peripheral blood of two groups; reverse transcription-polymerase chain reaction (RT-PCR) was adopted to analyze the mRNA levels of RORγT and Foxp3 in peripheral blood. In addition, we examined the levels of Th17 and CD4+ CD25+ Foxp3+ cells and associated factor levels in patients with remission after AL chemotherapy. the Th17 cells (CD3+ CD4+ IL-17+) in acute leukemia patients accounted for (1.51±0.27)%, which was significantly higher than that of control group (0.36±0.23)%, with statistical significance (t=20.51, P<0.001); the percentage of CD4+ CD25+ Foxp3+ cells in AL patients was (3.37±0.48)%, which was significantly higher than that of control group of (1.26±0.27)%, with statistical significance (t=24.23, P<0.001); the serum levels of IL-17 and TGF-ß in AL patients were (28.12±6.33) pg/ml and (38.41±8.44) pg/ml respectively, which were all significantly higher than that of control group of (14.41±6.21) pg/ml and (24.49±7.42) pg/ml, with statistical significance (t=7.83, P<0.001; t=7.83, P<0.001); the RORγT mRNA and Foxp3 mRNA levels in AL patients were all significantly higher than that of control group, with statistical significance (t=12.27, P<0.001; t=7.89, P<0.001). In addition, compared with before chemotherapy, the levels of Th17 cells and CD4+ CD25+ Foxp3+ cells, and the serum levels of IL-17 and TGF-ß in acute leukemia patients all decreased significantly after 6 months of chemotherapy, and the difference was statistically significant (P<0.001). Th17 cells, CD4+ CD25+ Foxp3+ cells and their secretory proteins IL-17, TGF-ß and transcription factors were significantly increased in AL patients. Therefore, regular detection of peripheral blood Th17 and Treg cells, as well as their secretory proteins are useful for monitoring the immune status and prognosis of patients.

Scaffold-based design of xanthine as highly potent inhibitors of DPP-IV for improving glucose homeostasis in DIO mice.

Diabetes mellitus, commonly characterized by hyperglycemia, is a group of metabolic diseases. Some oral anti-diabetic drugs show poor tolerability during chronic treatment, and associate with undesired side effects. Recent advances in the understanding of physiological functions of incretins and their degrading enzyme dipeptidyl peptidase DPP-IV have led to the discovery of DPP-IV inhibitors as a new class of oral anti-diabetic drugs. Several DPP-IV inhibitors have different chemical structures of which the xanthine scaffold has specific advantages. Combining previous work with the research strategy of pharmacophore hybridization, we retained this scaffold and synthesized a new series of amino-alcohol or diamino-modified xanthine compounds. Some xanthines exhibited submicromolar inhibitory activities against DPP-IV. The most potent compound 40 [Formula: see text] exhibits a good in vivo efficacy in reducing glucose excursion at a single dose and a better chronic effect in reducing body weight than metformin in DIO mice. In other words, the combined effect improved the pathological state of DIO mice.

Simultaneous removal of ammonium and nitrate by HDTMA-modified zeolite.

In this study, surfactant (hexadecyltrimethylammonium, HDTMA) modified zeolite (clinoptilolite) (SMZ) was used for simultaneous removal of ammonium and nitrate in wastewater, and the sorption properties of SMZ were determined. Results showed that natural clinoptilolite had good affinity for ammonium, but low sorption ability for nitrate, and the ammonium sorption process was well described by the pseudo-second order kinetic model. The SMZ had a significant enhancement on nitrate sorption and could simultaneously remove ammonium and nitrate at specific conditions, with removal efficiency up to 93.6% and 81.8%, respectively. The sorption process fitted well with the Langmuir isotherm. Orthogonal experiments showed that ammonium concentration was the most important factor for ammonium sorption on SMZ. However, surfactant loading was the major factor for nitrate sorption. Meanwhile, phosphate did not interfere with nitrate removal. Semi-empirical quantum mechanics molecular simulation indicated that electrostatic attraction existed between HDTMA and nitrate. Results of this study demonstrated that SMZs may have great potential for removing cations and anions simultaneously in the aquatic environment.

Synthesis and biological evaluation of 4-oxoquinoline-3-carboxamides derivatives as potent anti-fibrosis agents.

Thirty-one 4-oxoquinoline-3-carboxamides derivatives were synthesized and evaluated for their anti-fibrotic activities by the inhibition of TGF-ß1-induced total collagen accumulation and anti-inflammatory activities by the inhibition of LPS-stimulated TNF-α production. Among them, three compounds (10a, 10l and 11g) exhibited potent inhibitory effects on both TGF-ß1-induced total collagen accumulation and LPS-stimulated TNF-α production. Furthermore, oral administrations of 10l at a dose of 20 mg/kg/day for 4 weeks effectively alleviated lung inflammation and injury, and decreased lung collagen accumulation in bleomycin-induced pulmonary fibrosis model. Histopathological evaluation of lung tissue confirmed 10l as a potential, orally active agent for the treatment of pulmonary fibrosis.

Synthesis, structure-activity relationships and biological evaluation of barbigerone analogues as anti-proliferative and anti-angiogenesis agents.

A series of barbigerone analogues (7a-7w, 13a-13x) were designed, synthesized and biologically evaluated for their anti-proliferative and anti-angiogenic activities. Among these compounds, compound 13a exhibited the most potent inhibitory effect on the proliferation of HUVECs, HepG2, A375, U251, B16, and HCT116 cells (IC50=3.80, 0.28, 1.58, 3.50, 1.09 and 0.68 µM, respectively). Compound 13a inhibited the angiogenesis in zebrafish embryo assay in a concentration-dependent manner. Furthermore, 13a also effectively inhibited the migration and capillary like tube formation of human umbilical vein endothelial cell in vitro. These results support the further investigation of this class of compounds as potential anti-proliferative and anti-angiogenesis agents.

Design, synthesis and biological evaluation of a series of pyrano chalcone derivatives containing indole moiety as novel anti-tubulin agents.

A new series of pyrano chalcone derivatives containing indole moiety (3-42, 49a-49r) were synthesized and evaluated for their antiproliferative activities. Among all the compounds, compound 49b with a propionyloxy group at the 4-position of the left phenyl ring and N-methyl-5-indoly on the right ring displayed the most potent cytotoxic activity against all tested cancer cell lines including multidrug resistant phenotype, which inhibits cancer cell growth with IC50 values ranging from 0.22 to 1.80µM. Furthermore, 49b significantly induced cell cycle arrest in G2/M phase and inhibited the polymerization of tubulin. Molecular docking analysis demonstrated the interaction of 49b at the colchicine binding site of tubulin. In experiments in vivo, 49b exerted potent anticancer activity in HepG2 human liver carcinoma in BALB/c nude mice. These results indicated these compounds are promising inhibitors of tubulin polymerization for the potential treatment of cancer.

Discovery and identification of PIM-1 kinase inhibitors through a hybrid screening approach.

PIM-1 kinase is an important therapeutic target in the treatment of cancer. Discovery and identification of PIM-1 Inhibitors with novel scaffolds are an effective way for developing potent therapeutic agents for the treatment of cancers. Here we proposed a hybrid screening approach which combines an optimal structure-based drug design strategy and a simple pharmacophore model to discover PIM-1 kinase inhibitors. With the proposed hybrid screening approach, the SPECS database containing 204,580 molecules was screened. In total, 89 hits were obtained. Forty three of them were purchased and tested in bioassays. Finally, 5 lead compounds with novel scaffolds were identified to exhibit promising antitumor activities against human leukemia cell line MV4-11, K-562 and human prostate cancer cell line PC-3 and DU145. Their IC(50) values range from 4.40 to 37.96 µM. Three hits with 3 different scaffolds were selected from these five hits for binding mode analysis. It was demonstrated that the subtle differences in the interactions of the representatives with PIM-1 kinase contribute to the different inhibitory activities. It was also demonstrated that the suggested hybrid screening approach is an effective method to discover PIM-1 inhibitors possessing different scaffolds. These leads have a strong likelihood to act as further starting points for us in the optimization and development of potent PIM-1 inhibitors.

Pyrrolidine-mediated direct preparation of (e)-monoarylidene derivatives of homo- and heterocyclic ketones with various aldehydes.

An efficient method for the facile synthesis of (E)-monoarylidene derivatives of homo- and heterocyclic ketones with various aldehydes in the presence of a pyrrolidine organocatalyst has been achieved. A range of α,ß-unsaturated ketones were obtained in moderate to high yields (up to 99%). Unlike the Claisen-Schmidt condensation process, the formation of undesired bisarylidene byproducts is not observed. The possible reaction mechanism suggests that the reaction proceeds via a Mannich-elimination sequence.

Synthesis, preliminary structure-activity relationships, and in vitro biological evaluation of 6-aryl-3-amino-thieno[2,3-b]pyridine derivatives as potential anti-inflammatory agents.

In our previous study, a series of 6-aryl-3-amino-thieno[2,3-b]pyridine derivatives exhibited potent antiproliferative activities and an unique hepatocellular carcinoma (HCC)-specific anticancer activity was also observed. In further anti-inflammatory research, thienopyridine derivative 1a showed potent inhibition of nitric oxide (NO) production. So a series of thienopyridine analogues of 1a were synthesized and evaluated for anti-inflammatory activities. The structure-activity relationships (SARs) revealed that the most potent analogues 1f and 1o were identified as potent inhibitors of NO production with IC50 values of 3.30 and 3.24 µM, respectively. These results suggest that these 6-aryl-3-amino-thieno[2,3-b]pyridine derivatives might potentially constitute a novel class of anti-inflammatory agents, which require further studies.

Design, synthesis and biological evaluation of millepachine derivatives as a new class of tubulin polymerization inhibitors.

A series of novel tubulin polymerization inhibitors (9a-9p) have been synthesized and evaluated for their in vitro and in vivo biological activities. Among these compounds, 9e displayed strong antiproliferative activity against several tumor cell lines (IC50=0.15-0.62µM). Compound 9e was also shown to arrest cells in the G2/M phase of the cell cycle and inhibit the polymerization of tubulin. Molecular docking studies suggested that 9e binds into the colchicine binding site of tubulin. In xenograft experiments, 9e exerted more potent anticancer effect than anticancer drug taxol against the H460 Human lung carcinoma in BALB/c nude mice. In summary, these findings suggest that 9e is a promising new antimitotic compound for the potential treatment of cancer.

Synthesis of novel spirooxindolo-pyrrolidines, pyrrolizidines, and pyrrolothiazoles via a regioselective three-component [3+2] cycloaddition and their preliminary antimicrobial evaluation.

A series of spirooxindolo-pyrrolidines, pyrrolizidines, and pyrrolothiazoles hybrid compounds were prepared in good yields by regioselective, three-component, 1,3-dipolar cycloaddition reactions between α, ß-unsaturated ketones with furanyl substituents and unstable azomethine ylides, which were generated in situ from isatin and various types of amino acids. The synthesized compounds were screened for their antibacterial activities against a spectrum of pathogens. Preliminary studies identified compound 5c as a potent antimicrobial agent against drug-resistant bacteria. In addition, molecular docking studies indicated that compound 5c showed strong interactions with the active sites of lanosterol demethylase, dihydrofolate reductase, and topoisomerase II. This study provides an effective entry to the rapidly construction of a chemical library of heterocycles and compound 5c is one potent antibacterial lead for subsequent optimization.

Combination of pharmacophore hypothesis, genetic function approximation model, and molecular docking to identify novel inhibitors of S6K1.

S6K1 has emerged as a potential target for the treatment for obesity, type II diabetes and cancer diseases. Discovery of S6K1 inhibitors has thus attracted much attention in recent years. In this investigation, a hybrid virtual screening method that involves pharmacophore hypothesis, genetic function approximation (GFA) model, and molecular docking technology has been used to discover S6K1 inhibitors especially with novel scaffolds. The common feature pharmacophore hypothesis and GFA regression model of S6K1 inhibitors were first developed and applied in a virtual screen of the Specs database for retrieving S6K1 inhibitors. Then, the molecular docking method was carried out to re-filter these screened compounds. Finally, 60 compounds with promising S6K1 inhibitory activity were carefully selected and have been handed over to the other group to complete the follow-up compound synthesis (or purchase) and activity test.