Knockdown of ZEB2-AS1 inhibits cell proliferation, invasion and induces apoptosis in osteosarcoma by combining with EZH2.

OBJECTIVE: This study aims to explore whether ZEB2-AS1 can promote the development of osteosarcoma by affecting the proliferation, invasion, and apoptosis of osteosarcoma cells. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect the ZEB2-AS1 expression in osteosarcoma tissue specimens and normal bone tissues. After ZEB2-AS1 downregulation, Cell Counting Kit-8 (CCK-8) test, plate cloning assay, 5-Ethynyl-2'-deoxyuridine (EdU) experiment, and flow cytometry were conducted to analyze the changes in cell proliferation and apoptosis. RIP assay was performed to detect the binding of ZEB2-AS1 to EZH2, while Western blot was applied to examine the EZH2 expression after EZH2 was inhibited. Meanwhile, after simultaneously inhibiting ZEB2-AS1 and EZH2, the cell invasiveness was determined by transwell assay. RESULTS: ZEB2-AS1 was highly expressed in osteosarcoma tissues, especially in advanced and metastatic groups. Interfering with ZEB2-AS1 suppressed cell proliferation and enhanced cell apoptosis. In addition, ZEB2-AS1 was confirmed to be able to combine with EZH2. The knockdown of ZEB2-AS1 attenuated the cell invasion ability, which was further decreased after the simultaneous downregulation of ZEB2-AS1 and EZH2. CONCLUSIONS: The long non-coding RNA, ZEB2-AS1, enhanced the proliferation and invasion of osteosarcoma cells and inhibited the cell apoptosis by combining with EZH2, and thereby promoted the development of osteosarcoma.

[A cohort study of abnormal routine blood test results in landfill workers].

Objective: To investigate the abnormalities of the blood system in landfill workers. Methods: A cohort study was conducted for 224 landfill workers who were followed up for 6 consecutive years with abnormal routine blood test results and a low platelet count as the outcome events. The life-table method was used to analyze the incidence rates of these two outcome events, and the incidence rates were compared between first-and second-line workers. Results: A total of 71 workers had abnormal routine blood test results, among whom 29 had abnormal leukocyte count, 14 had abnormal erythrocyte count, 40 had abnormal platelet count, 17 had abnormal hemoglobin, and 29 had a reduction in platelet count. For these landfill workers, the 6-year abnormal rate of routine blood test results was 43.2%, and the incidence rate of low platelet count within 6 years was 13.5%. The first-line workers had a significantly lower abnormal rate of routine blood test results than the second-line workers (P=0.020) , and the relative risk of abnormal routine blood test results in the first-and second-line workers was 0.592. There was no significant difference in the incidence rate of low platelet count between the two groups of workers (P≥0.05) . Conclusion: The landfill has an adverse effect on the blood system of landfill workers, and the second-line workers have greater impairment than the first-line workers.

Effects of the conditioned medium of mesenchymal stem cells on mouse oocyte activation and development

Mesenchymal stem cells (MSCs) have been reported to secrete a variety of cytokines and growth factors acting as trophic suppliers, but little is known regarding the effects of conditioned medium (CM) of MSCs isolated from femurs and tibias of mouse on the artificial activation of mouse oocytes and on the developmental competence of the parthenotes. In the current study, we investigated the effect of CM on the events of mouse oocyte activation, namely oscillations of cytosolic calcium concentration ([Ca²+]i), meiosis resumption, pronucleus formation, and parthenogenetic development. The surface markers of MSCs were identified with a fluorescence-activated cell sorter. The dynamic changes of the spindle and formation of pronuclei were examined by laser-scanning confocal microscopy. Exposure of cumulus-oocyte complexes to CM for 40 min was optimal for inducing oocyte parthenogenetic activation and evoking [Ca²+]i oscillations similar to those evoked by sperm (95 vs 100 percent; P > 0.05). Parthenogenetically activated oocytes immediately treated with 7.5 µg/mL cytochalasin B (CB), which inhibited spindle rotation and second polar body extrusion, were mostly diploid (93 vs 6 percent, P < 0.01) while CB-untreated oocytes were mostly haploid (5 vs 83 percent, P < 0.01). Consequently, the blastocyst rate was higher in the CB-treated than in the CB-untreated oocytes. There was no significant difference in developmental rate between oocytes activated with CM and 7 percent ethanol (62 vs 62 percent, P > 0.05), but the developmental competence of the fertilized oocytes was superior to that of the parthenotes (88 vs 62 percent, P < 0.05). The present results demonstrate that CM can effectively activate mouse oocytes, as judged by the generation of [Ca²+]i oscillations, completion of meiosis and parthenogenetic development.

Effects of the conditioned medium of mesenchymal stem cells on mouse oocyte activation and development.

Mesenchymal stem cells (MSCs) have been reported to secrete a variety of cytokines and growth factors acting as trophic suppliers, but little is known regarding the effects of conditioned medium (CM) of MSCs isolated from femurs and tibias of mouse on the artificial activation of mouse oocytes and on the developmental competence of the parthenotes. In the current study, we investigated the effect of CM on the events of mouse oocyte activation, namely oscillations of cytosolic calcium concentration ([Ca(2)+]i), meiosis resumption, pronucleus formation, and parthenogenetic development. The surface markers of MSCs were identified with a fluorescence-activated cell sorter. The dynamic changes of the spindle and formation of pronuclei were examined by laser-scanning confocal microscopy. Exposure of cumulus-oocyte complexes to CM for 40 min was optimal for inducing oocyte parthenogenetic activation and evoking [Ca(2)+]i oscillations similar to those evoked by sperm (95 vs 100%; P > 0.05). Parthenogenetically activated oocytes immediately treated with 7.5 microg/mL cytochalasin B (CB), which inhibited spindle rotation and second polar body extrusion, were mostly diploid (93 vs 6%, P < 0.01) while CB-untreated oocytes were mostly haploid (5 vs 83%, P < 0.01). Consequently, the blastocyst rate was higher in the CB-treated than in the CB-untreated oocytes. There was no significant difference in developmental rate between oocytes activated with CM and 7% ethanol (62 vs 62%, P > 0.05), but the developmental competence of the fertilized oocytes was superior to that of the parthenotes (88 vs 62%, P < 0.05). The present results demonstrate that CM can effectively activate mouse oocytes, as judged by the generation of [Ca(2)+]i oscillations, completion of meiosis and parthenogenetic development.

Herbal plants as a promising source of natural antifoulants: evidence from barnacle settlement inhibition.

A series comprising hexane, ethyl acetate, ethanol and aqueous extracts from six common Chinese herbs (Carpesium abrotanoides, Melia toosendan, Cnidium monnieri, Vitex negundo, Stemona sp. and Sophora flavescens) was investigated for antifouling (AF) activity against cypris (cyprids) larvae of the barnacle Balanus albicostatus. All extracts tested except the aqueous extract from Stemona sp. significantly inhibited the settlement of cyprids, the most potent being the ethyl acetate extract of S. flavescens (EC(50) value 2.08 microg ml(-1)), from which an AF compound, identified as 2'-methoxykurarinone, was isolated using bioassay-guided procedures. Furthermore, the AF activity of this compound was found to be highly reversible and greater than that of the three other natural products from S. flavescens, namely matrine, oxymatrine and oxysophocarpine. These compounds have been used commercially in China for their pharmaceutical activities, but their AF activities have not previously been evaluated. Analysis of structure-activity relationships suggested that the N-1 nitrogen atom in matrine plays a crucial role in AF activity. Overall, the present findings indicate that herbal plants are a valuable source of novel AF agents.

Effect of conditioned medium of mesenchymal stem cells on the in vitro maturation and subsequent development of mouse oocyte.

Mesenchymal stem cells (MSCs) secrete a variety of cytokines and growth factors in addition to self-renewal and multiple forms of differentiation. Some of these secreted bioactive factors could improve meiotic maturation in vitro and subsequent embryo developmental potential. The aim of the present study was to determine whether in vitro maturation (IVM) of mouse oocyte with or without cumulus cells could be improved by contact with conditioned medium (CM) of MSCs as well as the efficiency of CM to support follicular growth and oocyte maturation in the ovarian organ of mice cultured on soft agar. The developmental potential of matured oocyte was assessed by blastocyst formation after in vitro fertilization (IVF). Germinal vesicle stage oocytes with or without cumulus cells were subjected to IVM in either CM, Dulbecco's modified Eagle's medium (DMEM), alpha-minimum essential medium (alpha-MEM) or human tubal fluid (HTF). Approximately 120 oocytes were studied for each medium. CM produced a higher maturation rate (91.2%) than DMEM (54.7%), alpha-MEM (63.5%) and HTF (27.1%). Moreover, CM improved embryo development to blastocyst stage significantly more than DMEM and HTF (85 vs 7% and 41.7%, respectively) but there was no significant difference compared with alpha-MEM (85 vs 80.3%). The behavior of cortical granules of IVM oocytes cultured in CM revealed cytoplasmic maturation. Moreover, CM also supported preantral follicles growth well in organotypic culture on soft agar resulting in the maturation of 60% of them to developmentally competent oocytes. The production of estrogen progressively increased approximately 1-fold every other day during organ culture, while a dramatic 10-fold increase in progesterone was observed 17 h after human chorionic gonadotropin stimulus at the end of culture. Thus, CM is an effective medium for preantral follicle growth, oocyte maturation, and sequential embryo development.

Effect of conditioned medium of mesenchymal stem cells on the in vitro maturation and subsequent development of mouse oocyte

Mesenchymal stem cells (MSCs) secrete a variety of cytokines and growth factors in addition to self-renewal and multiple forms of differentiation. Some of these secreted bioactive factors could improve meiotic maturation in vitro and subsequent embryo developmental potential. The aim of the present study was to determine whether in vitro maturation (IVM) of mouse oocyte with or without cumulus cells could be improved by contact with conditioned medium (CM) of MSCs as well as the efficiency of CM to support follicular growth and oocyte maturation in the ovarian organ of mice cultured on soft agar. The developmental potential of matured oocyte was assessed by blastocyst formation after in vitro fertilization (IVF). Germinal vesicle stage oocytes with or without cumulus cells were subjected to IVM in either CM, Dulbecco's modified Eagle's medium (DMEM), alpha-minimum essential medium (alpha-MEM) or human tubal fluid (HTF). Approximately 120 oocytes were studied for each medium. CM produced a higher maturation rate (91.2%) than DMEM (54.7%), alpha-MEM (63.5%) and HTF (27.1%). Moreover, CM improved embryo development to blastocyst stage significantly more than DMEM and HTF (85 vs 7% and 41.7%, respectively) but there was no significant difference compared with alpha-MEM (85 vs 80.3%). The behavior of cortical granules of IVM oocytes cultured in CM revealed cytoplasmic maturation. Moreover, CM also supported preantral follicles growth well in organotypic culture on soft agar resulting in the maturation of 60% of them to developmentally competent oocytes. The production of estrogen progressively increased approximately 1-fold every other day during organ culture, while a dramatic 10-fold increase in progesterone was observed 17 h after human chorionic gonadotropin stimulus at the end of culture. Thus, CM is an effective medium for preantral follicle growth, oocyte maturation, and sequential embryo development.

Abnormal temperature dependence of photoemission intensity mediated by thermally driven reorientation of a monomolecular film.

The photoemission intensities of organic molecular layers generally obey the Debye-Waller temperature dependence but not always. With the example of a monomolecular film formed from [1,1';4',1''-terphenyl]-4,4''-dimethanethiol, we show that pronounced deviations from Debye-Waller temperature behavior are possible and are likely caused by temperature-dependent changes in molecular orientation.

Photohole screening effects in polythiophenes with pendant groups.

We compare two mechanisms that dominate the temperature-dependent changes in electronic structure for poly(3-hexylthiophene-2,5 diyl) (P3HT). Structural changes in the relative orientation and configuration of the aromatic ring backbone are observed to occur over a wide range in temperature and affect the local final state screening in photoemission. There are also changes in conductivity and carrier concentration at lower temperatures leading to altered long-range intramolecular screening of photoholes and final state effects that affect excitation spectroscopies including photoemission. For polyethylenedioxythiophene (PEDOT), temperature-dependent changes in the structure and configuration of the polymer backbone are not as significant, although temperature-dependent final state effects are observed.