Search

To study the effects of attenuated Salmonella typhimurium L forms on the in vivo tumorigenicity and apoptosis of murine epithelial ovarian cancer cells, as well as the related mechanisms. Attenuated Salmonella typhimurium VNP20009 was induced into bacterial L forms by using antibiotic ceftriaxone. CCK-8 cell proliferation assay showed that attenuated S. typhimurium L forms can inhibit the proliferation of murine ovarian epithelial cancer ID8 cells. Attenuated ST L forms can induce apoptosis and inhibit invasion ability of epithelial ovarian cancer cells in vitro. TUNEL assay showed that attenuated ST L forms can induce apoptosis of ID8 cells in murine ovarian tumors. Meanwhile, attenuated ST L forms inhibit tumor growth in murine ovarian tumors. The tumorigenicity-related proteins of xenograft tumors detected by immunohistochemistry and fluorescence quantitative RT-PCR assays showed that attenuated ST L forms can reduce the expression of proteins that promote tumor growth and metastasis, such as Lgals9 and MMP9. This study confirmed that attenuated ST L forms can suppress tumor growth and promote apoptosis in murine ovarian tumors. Attenuated ST L forms may serve as a novel biological agent for bacterial-mediated tumor therapy in epithelial ovarian cancer. [ABSTRACT FROM AUTHOR]

In this work, the forestry wastes are converted into a series of porous carbons using H3PO4 activation. These porous carbons feature a large specific surface area (1045.20 m2 g−1) and porosity that combines micro‐, meso‐, and macropores in various amounts depending on the fuel properties recorded for precursors used. Importantly, the C content recorded for forestry waste is one of the crucial factors in defining the specific surface area of the derived porous carbons. In addition, the total capacitance of the pine‐sawdust‐based porous carbon (PS‐C) sample is the highest, such as 220.55 F g−1 upon 5 mV s−1. Notably, the electrical double‐layer capacitance recorded for the samples remains essentially constant with increasing scan rates, such as ≈91.50 F g−1 for the olive‐shell‐based porous carbon, ≈123.70 F g−1 for PS‐C, and ≈105.66 F g−1 for the pine‐needle‐based porous carbon. Encouragingly, the pore‐associated sp3 site holds significant roles in the electrochemical application of the porous carbons. More importantly, the O/C value recorded for the precursor can be employed as a universal predictor of electrochemically active sites produced in porous carbons. In the findings, crucial insights are exhibited into the optimized fabrication of porous carbon with target electrochemically active sites for other applications such as catalysis. [ABSTRACT FROM AUTHOR]

Background: Epithelial ovarian cancer (EOC) is a pathological type with a higher mortality rate among gynecological cancers today. Long-chain noncoding RNAs (lncRNAs) can regulate the transcription and expression of cellular genes. However, the downstream molecules regulated by lncRNA HOTAIR have not been well studied. The effects of downregulated lncRNA HOTAIR on EOC invasiveness and tumorigenicity in nude mice, along with TGF- β1 and ZEB1 in epithelial ovarian cancer cells, need to be investigated in further research. Results: RT-qPCR was used to detect lncRNA HOTAIR and TGF-β1 and ZEB1 mRNA expression in EOC SKOV3 cells. The expression of lncRNA HOTAIR in SKOV3 cells transfected with the recombinant shHOTAIR interference plasmid was significantly lower than that of the negative control. Compared with the negative control, the matrix gel invasion ability of shHOTAIR SKOV3 cells in vitro and their tumorigenicity in nude mice were significantly reduced. Moreover, compared with the control, the expression of ZEB1 protein in shHOTAIR-SKOV3 xenograft tumors was significantly reduced. Downregulation of lncRNA HOTAIR expression significantly reduced TGF-β1 and ZEB1 mRNA expression, but increased the expression of E-cadherin mRNA. In summary, downregulated lncRNA HOTAIR in EOC SKOV3 cells transfected with shHOTAIR can inhibit TGF-β1, reduce ZEB1, increase E-cadherin, and significantly reduce the invasiveness and tumorigenicity of ovarian epithelial cancer SKOV3 cells. Conclusions: These results suggest that the lncRNA HOTAIR may be an effective target for the treatment of human EOC. [ABSTRACT FROM AUTHOR]

The environment has been heavily contaminated with tetracycline (TC) due to its excessive use; however, activated carbon possessing well-developed pores can effectively adsorb TC. This study synthesized pinecone-derived activated carbon (PAC) with high specific surface area (1744.659 cm2/g, 1688.427 cm2/g) and high adsorption properties (840.62 mg/g, 827.33 mg/g) via hydrothermal pretreatment methods utilizing pinecones as precursors. The results showed that PAC treated with 6% KOH solution had excellent adsorption properties. It is found that the adsorption process accords with the PSO model, and a large amount of C=C in PAC provides the carrier for π-πEDA interaction. The results of characterization and the isothermal model show that TC plays a key role in the adsorption process of PAC. It is concluded that the adsorption process of TC on PAC prepared by hydrothermal pretreatment is mainly pore filling and π-πEDA interaction, which makes it a promising adsorbent for TC adsorption. [ABSTRACT FROM AUTHOR]

Torrefaction is a process of mild pyrolysis at 200–300 °C under nitrogen atmosphere and has been considered to be an effective way to improve the properties of biomass. In this study, lignin was subjected to torrefaction at 200 °C, 230 °C, 260 °C, and 290 °C. Thermogravimetric analysis of lignin samples was performed at a temperature ramp of 25 to 550 °C with the heating rates of 10, 20, 30, or 40 °C min−1. A distributed activation energy model was used to analyze the pyrolysis kinetics of lignin. Then, the lignin samples were subjected to pyrolysis at 600 °C for 10 s. The results showed that torrefaction had a significant effect on the physicochemical properties and pyrolysis characteristics of lignin. Among the torrefied samples, the sample treated at 290 °C exhibited the lowest mass yield (86.07%), lowest energy yield (93.25%), highest content of carbon (63.76%), highest higher heating value (25.18 MJ kg−1), and lowest content of oxygen (30.25%). The activation energy of torrefied lignin samples slightly changed in comparison with those of the raw samples. Torrefaction has a significant effect on pyrolysis products. The peak area % of S-type (41.4%) and P-type (5.4%) phenols in the bio-oil obtained by pyrolysis of LN-200 was the highest. [ABSTRACT FROM AUTHOR]

In this study, soybean straw pellets (SSP) and pine wood pellets (PWP) were used as materials for torrefaction at 200–350 °C. Impacts of torrefaction temperature on the physicochemical properties, hydrophobicity, and mechanical properties of the pellets were investigated. Results showed that some oxygen-containing functional groups in the biomass pellets disappeared during torrefaction, and the oxygen content significantly decreased. The hydrophobic behavior of biomass is highly affected by their chemical composition. A significant decrease in hemicellulose content was observed in torrefied pellets. Consequently, the equilibrium moisture content of torrefied pellets decreased significantly; and the torrefied PWP remained intact even after immersion of more than 2 h in water. As the torrefaction temperature increased, the cellulose and lignin started to decompose and formed more micropores. Meanwhile, the torrefied pellets became less dense, which lowered the mechanical properties of the pellets. Optimal temperature for the preparation of high-quality torrefied SSP and torrefied PWP was found to be 250 °C and 300 °C, respectively, since higher temperatures cause excessive loss of volatiles and degradation of mechanical properties without significantly enhancing the high heating value of torrefied pellets. [ABSTRACT FROM AUTHOR]

Two types of nanocellulose (cellulose nanocrystals—CNCs and cellulose nanofibrils—CNFs) were isolated from two biomass resources. The morphology, crystallinity and thermal stability of the nanocelluloses were systematically compared in this paper. CNCs derived from rice straw (CNC-Rs) and poplar wood (CNC-Ps) by sulfuric acid hydrolysis had short rod-shaped structures and average diameters of 9.1 nm for CNC-Rs and 11.4 nm for CNC-Ps. CNFs derived from rice straw (CNF-Rs) and poplar wood (CNF-Ps) by grinding had web-network structures and average diameters of 13.3 nm for CNF-Rs and 18.5 nm for CNF-Ps. After freeze-drying, the CNCs and CNFs retained their nano structures. CNFs and CNC-Ps consisted of the typically pure cellulose I, while CNC-Rs consisted of cellulose I and II. The CrI of the nanocellulose followed the order of CNC-Ps (72.9%) > CNC-Rs (68.0%) > CNF-Ps (56.4%) > CNF-Rs (54.4%). The thermal stability of the nanocellulose was correlated with their source biomass materials and preparation method, which led to the differences in their dimensions, crystallinity, and sulfate groups. Nanocellulose isolated from poplar wood showed the slightly higher thermal stability than that of nanocellulose from rice straw. CNFs exhibited the higher thermal stability than that of CNCs. The apparent activation energy (E) was calculated to evaluate the degradation process. The nanocellulose had E of 85.17–101.98 kJ/mol for CNCs and 94.92–108.76 kJ/mol for CNFs. [ABSTRACT FROM AUTHOR]

Zinc-finger E-box binding homeobox 1 (ZEB1) is a master regulator of epithelial-mesenchymal transition (EMT) and has been implicated in primary epithelial cancer biological processes, such as invasion and metastasis. However, the role of ZEB1 in progression of melanoma and cancer stem cells (CSCs) remains obscure. In this study, the recombinant plasmids of t3 shRNAs targeting mouse ZEB1 were constructed and transfected into melanoma B16F10 cells. The stable transfected cells were selected and the characteristics of ZEB1 downregulated B16F10 cells was assessed. The tumourigenicity of CD44+CD133+CSCs isolated from B16F10 cells stably transfected with the ZEB1-shRNA2 recombinant was also assessed. ZEB1-shRNAs B16F10 showed a lower expression of ZEB1 and vimentin, weaker migration, invasiveness, colony forming, and proliferation, and a lower tumourigenicity than the control cells. The tumourigenicity of the ZEB1-shRNA2 CD44+CD133+CSCs was also inhibited. In conclusion, ZEB1-shRNA2-mediated downregulation of ZEB1 expression in B16F10 cells and CSCs is involved in the inhibition of the EMT process. ZEB1 may be a potential target in melanoma targeted. [ABSTRACT FROM AUTHOR]

Studies from hematopoietic origin malignancies have demonstrated that multiple myeloma contain a rare population of cancer stem cells (CSCs) that are responsible for tumor multiresistance and recurrence. The goal of this study was to investigate targeted therapeutic effect of anti-ABCG2 monoclonal antibody (McAb) combined with silver nanoparticles (AgNPs) and vincristine (VCR) on myeloma CSCs. The characteristics of CD44 + CD24 − cells that were isolated from the SP2/0 cells using magnetic activated cell sorting system were first identified. The results showed that the CD44 + CD24 − cells exhibited higher proliferation, more colony formation, more side population fraction, and stronger tumorigenicity in BALB/c mice than the control cells. Moreover, CD44 + CD24 − cells markedly up-regulated the ABCG2 expression, however, anti-ABCG2 McAb combined with AgNPs and VCR effectively inhibited the CD44 + CD24 − cell growth and prolonged the survival of myeloma-bearing mice. We concluded that the CD44 + CD24 − cells in mouse myeloma SP2/0 cell line posses CSC properties. Anti-ABCG2 McAb combined with AgNPs and VCR provide an efficient targeted therapeutic method for inhibiting myeloma CD44 + CD24 − CSC growth in mice. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) still remains an incurable disease in spite of extending the patient survival by new therapies. The hypothesis of cancer stem cells (CSCs) states that although chemotherapy kills most tumor cells, it is believed to leave a reservoir of CSCs that allows the tumor cell propagation. The objective of this research was to evaluate the therapeutic effect of new paclitaxel-FeO nanoparticles (PTX-NPs) with an average size range of 7.17 ± 1.31 nm on MM CSCs in vitro. The characteristics of CD138CD34 cells, isolated from human MM RPMI 8226 and NCI-H929 cell lines by the magnetic associated cell sorting method, were identified by the assays of colony formation, cell proliferation, drug resistance, cell migration, and tumorigenicity in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, respectively. Inhibitory effects of PTX-NPs on CD138CD34 cells were evaluated by a variety of assays in vitro. The results showed that the CD138CD34 cells were capable of forming colonies, exhibited high proliferative and migratory ability, possessed a strong drug resistance, and had powerful tumorigenicity in NOD/SCID mice compared to non-CD138CD34 cells. PTX-NPs significantly inhibited CD138 CD34 cell viability and invasive ability, and resulted in G0/G1 cell cycle arrest and apoptosis compared with PTX alone. We concluded that the CD138CD34 phenotype cells might be CSCs in RPMI 8226 and NCI-H929 cell lines. PTX-NPs had an obvious inhibitory effect on MM CD138CD34 CSCs. The findings may provide a guideline for PTX-NPs' treatment of MM CSCs in preclinical investigation. [ABSTRACT FROM AUTHOR]

Drying characteristics of cotton stalk were investigated at four temperatures (60, 80, 100 and 120 °C) using a simultaneous thermal analyzer (TG-DSC). Heat requirements of cotton stalk during drying were calculated ranging from 189 to 406 kJ/kg. Consequently, Midilli-Kucuk model showed the best fit to experimental drying data. The values of effective diffusivity ranged from 4.38 × 10 to 8.15 × 10 m/s, and the activation energy was calculated to be 11.6 kJ/mol. [ABSTRACT FROM AUTHOR]

The goal of this study was to investigate whether glycosylphosphatidylinositol (GPI)-anchored 6 kDa early secreted antigenic target (ESAT-6) and IL-21-producing B16F10/ESAT-6-GPI-IL-21 viable vaccine would induce antitumor efficacy. Mice were immunized with B16F10/ESAT-6-GPI-IL-21 vaccine and challenged by B16F10 cells 2 weeks later. Antitumor efficacy and mechanisms of the vaccine were analyzed. Vaccination with the viable B16F10/ESAT-6-GPI-IL-21 vaccine resulted in an increase of IFN-γ level and the CD8CTL cytotoxicity, a decrease in TGF-β generation and increase in the expression of miR-200c that serves as melanoma suppressor by directly targeting zinc-finger E-box binding homeobox 1 to inhibit epithelial-mesenchymal transition and block tumor metastasis. The vaccine significantly inhibited the melanoma growth, reduced the lung melanoma nodules, and prolonged the mouse survival compared with the controls. These findings highlighted IL-21 as an immune adjuvant in an engineered viable tumor vaccine to reinforce heterogenetic antigen ESAT-6 immune tolerance break to induce powerful antitumor efficacy in mice. [ABSTRACT FROM AUTHOR]

Ovarian cancer causes more deaths than any other cancer of the female reproductive system, and its overall cure rate remains low. The present study investigated human umbilical blood mononuclear cell (UBMC)-derived mesenchymal stem cells (UBMC-MSCs) as interleukin-21 ( IL-21) gene delivery vehicles for ovarian cancer therapy in nude mice. MSCs were isolated from UBMCs and the expanded cells were phenotyped by flow cytometry. Cultured UBMCs were differentiated into osteocytes and adipocytes using appropriate media and then the UBMC-MSCs were transfected with recombinant pIRES2-IL-21-enhancement green fluorescent protein. UBMC-MSCs expressing IL-21 were named as UBMC-MSC-IL-21. Mice with A2780 ovarian cancer were treated with UBMC-MSC-IL-21 intravenously, and the therapeutic efficacy was evaluated by the tumor volume and mouse survival. To address the mechanism of UBMC-MSC-IL-21 against ovarian cancer, the expression of IL-21, natural killer glucoprotein 2 domain and major histocompatibility complex class I chain-related molecules A/B were detected in UBMC-MSC-IL-21 and in the tumor sites. Interferon-γ-secreting splenocyte numbers and natural killer cytotoxicity were significantly increased in the UBMC-MSC-IL-21-treated mice as compared with the UBMC-MSCs or the UBMC-MSC-mock plasmid-treated mice. Most notably, tumor growth was delayed and survival was prolonged in ovarian-cancer-bearing mice treated with UBMC-MSC-IL-21. Our data provide important evidence that UBMC-MSCs can serve as vehicles for IL-21 gene delivery and inhibit the established tumor. [ABSTRACT FROM AUTHOR]

Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was employed to achieve fast pyrolysis of biomass and on-line analysis of the pyrolysis vapors. Four biomass materials (poplar wood, fir wood, cotton straw and rice husk) were pyrolyzed to reveal the difference among their products. Moreover, catalytic cracking of the pyrolysis vapors from cotton straw was performed by using five catalysts, including two microporous zeolites (HZSM-5 and HY) and three mesoporous catalysts (ZrO[sub2]&TiO[sub2], SBA-15 and Al/SBA-15). The results showed that the distribution of the pyrolytic products from the four materials differed a little from each other, while catalytic cracking could significantly alter the pyrolytic products. Those important primary pyrolytic products such as levoglucosan, hydroxyacetaldehyde and 1-hydroxy-2-propanone were decreased greatly after catalysis. The two microporous zeolites were effective to generate high yields of hydrocarbons, while the three mesoporous materials favored the formation of furan, furfural and other furan compounds, as well as acetic acid. [ABSTRACT FROM AUTHOR]