Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen...Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.展开更多
BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patie...BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are unknown.In this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation.AIM To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage.METHODS BMSC-exo were isolated from mouse BMSC media.This was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro analyses.The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of mice.RESULTS Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery.MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation.Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases.Furthermore,we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA.CONCLUSION We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain.展开更多
Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landra...Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landrace sows was significantly higher than that of low-yielding sows.However,the functions of miR-24-3p on GCs are unclear.In this study,using flow cytometry,5-ethynyl-2′-de-oxyuridine(EdU)staining,and cell count,we showed that miR-24-3p promoted the proliferation of GCs increasing the proportion of cells in the S phase and upregulating the expression of cell cycle genes,moreover,miR-24-3p inhibited GC apoptosis.Mechanistically,on-line prediction,bioinformatics analysis,a luciferase reporter assay,RT-qPCR,and Western blot results showed that the target gene of miR-24-3p in proliferation and apoptosis is cyclin-dependent kinase inhibitor 1B(P27/CDKN1B).Furthermore,the effect of miR-24-3p on GC proliferation and apoptosis was attenuated by P27 overexpression.These findings suggest that miR-24-3p regulates the physiological functions of GCs.展开更多
Background:Osteosarcoma(OS),recognized as the predominant malignant tumor originating from bones,necessitates an in-depth comprehension of its intrinsic mechanisms to pinpoint novel therapeutic targets and enhance tre...Background:Osteosarcoma(OS),recognized as the predominant malignant tumor originating from bones,necessitates an in-depth comprehension of its intrinsic mechanisms to pinpoint novel therapeutic targets and enhance treatment methodologies.The role of fat mass and obesity-associated(FTO)in OS,particularly its correlation with malignant traits,and the fundamental mechanism,remains to be elucidated.Materials and Methods:1.The FTO expression and survival rate in tumors were analyzed.2.FTO in OS cell lines was quantified utilizing western blot and PCR.3.FTO was upregulated and downregulated separately in MG63.4.The impact of FTO on the proliferation and migration of OS cells was evaluated using CCK-8,colony formation,wound healing,and Transwell assays.5.The expression of miR-150-5p in OS cells-derived exosomes was identified.6.The binding of miR-150-5p to FTO was predicted by TargetScan and confirmed by luciferase reporter assay.7.The impact of exosome miR-150-5p on the proliferation and migration of OS cells was investigated.Results:The expression of FTO was higher in OS tissues compared to normal tissues correlating with a worse survival rate.Furthermore,the downregulation of FTO significantly impeded the growth and metastasis of OS cells.Additionally,miR-150-5p,which was downregulated in both OS cells and their derived exosomes,was found to bind to the 3′-UTR of FTO through dual luciferase experiments.Exosomal miR-150-5p was found to decrease the expression of FTO and inhibit cell viability.Conclusions:We identified elevated levels of FTO in OS,which may be attributed to insufficient miR-150-5p levels in both the cells and exosomes.It suggests that the dysregulation of miR-150-5p and its interaction with FTO could potentially promote the development of OS.展开更多
Objective To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer(CRC).Methods The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser captu...Objective To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer(CRC).Methods The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR,respectively.Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p.The protein expressions of p53 and unc-51 like kinase 2(ULK2)in CRC cells were detected by western blot.Flow cytometry was used to detect cell cycle and apoptosis.Cell proliferation was measured by CCK8 and EdU assay.Results The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage.CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner,and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine.Moreover,ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues.Interestingly,ULK2 inhibited CRC cell proliferation in a p53-dependent manner.Furthermore,exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells.Conclusion Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC,which may offer promising targets for CRC prevention and therapy.展开更多
Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) is a bacterial pathogen of tomato and of the model plants Arabidopsis and Nicotiana benthamiana (N. benthamiana). Like numerous Gram-negative bacterial pathogens of ...Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) is a bacterial pathogen of tomato and of the model plants Arabidopsis and Nicotiana benthamiana (N. benthamiana). Like numerous Gram-negative bacterial pathogens of animals and plants, Pst DC3000 exploits the conserved type III secretion system (TTSS) to deliver multiple virulence effectors directly into the host cells. Type III effectors (T3Es) collectively participate in causing disease, by mechanisms that are not well clarity. Elucidating the virulence function of individual effector is fundamental for understanding bacterial infection of plants. Here, we focused on studying one of these effectors, HopAA1-1, and analyzed its potential function and subcellular localization in N. benthamiana. Using an Agrobacterium-mediated transient expression system, we found that HopAA1-1 can trigger domain-dependent cell death in N. benthamiana. The observation using confocal microscopy showed that the YFP-tagged HopAA1-1 localizes to diverse cellular components containing nucleus, cytoplasm and cell membrane, which was demonstrated through immunoblot analysis of membrane fractionation and nuclear separation. Enforced HopAA1-1 subcellular localization, by tagging with a nuclear localization sequence (NLS) or a nuclear export sequence (NES), shows that HopAA1-1-induced cell death in N. benthamiana is suppressed in the nucleus but enhanced in the cytoplasm. Our research is lay a foundation for revealed the molecular pathogenesis of Pseudomonas syringae pv. tomato.展开更多
Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption,...Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.展开更多
[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavo...[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavonoid glycosides were isolated and purified from the ethanol alcoholic extract of the roots of Liliaceae plant Chlorophytum comosum by silica gel column chromatography,macroporous resin column chromatography,Sephadex LH-20,and reverse column chromatography(ODS).The inhibitory activity of flavonoid glycosides on human nasopharyngeal carcinoma cells was analyzed by CCK-8 method,and the potential mechanism was preliminarily analyzed by molecular docking.[Results]Two flavonoid glycosides were identified as isovitexin 2″-0-rhamnoside and 7-2″-di-O-β-glucopyranosylisovitexin.Two flavonoid glycosides showed promising inhibitory effect on human nasopharyngeal carcinoma cell line 5-8F,with IC_(50) values of 24.8 and 27.5μmol/L,respectively.Molecular docking results showed that the potential targets of two flavonoid glycosides include CyclinD1,Bcl-2β-Catenin,ILK,TGF-β,in addition,two glycosides showed higher predicted binding affinity towards CyclinD1,which verifies the cytotoxicity of the two compounds on human nasopharyngeal carcinoma cell line 5-8F in vitro.[Conclusions]Two flavonoid glycosides are the active molecules in Chlorophytum comosum that can inhibit the proliferation of human nasopharyngeal carcinoma cells,and have the potential to be used in the research and development of anti nasopharyngeal carcinoma drugs.展开更多
A complex programmable logical device (CPLD) based on conventional embedded Flash memory process with 72 macro cells is studied in the paper. Compared with the Flash cell array technology employed by foreign compani...A complex programmable logical device (CPLD) based on conventional embedded Flash memory process with 72 macro cells is studied in the paper. Compared with the Flash cell array technology employed by foreign companies, this architecture exhibiting insystem reconfiguration and rapid response was manufactured by low cost fabrication process. The device architecture and critical cell design are also analyzed in detail in the paper. The CPLD was designed by full-custom ASIC technology and manufactured by 0.35 pm 3P3M Flash process with 72 macro cells and 5 V voltage supply. The measurement results indicate that the devices are able to operate above the frequency of 66.7 MHz with the pin delay less than 10 ns.展开更多
In multiple experiments plates of melanoma cells separated by either 3 m or 1.7 km were placed in the centers of toroids. A specific protocol of changing, angular velocity, pulsed magnetic fields that has been shown t...In multiple experiments plates of melanoma cells separated by either 3 m or 1.7 km were placed in the centers of toroids. A specific protocol of changing, angular velocity, pulsed magnetic fields that has been shown to produce excess correlation in photon durations and shift in proton concentrations (pH) in spring water were generated around both plates of cells. Serial injections of 50 μL of standard concentrations of hydrogen peroxide into the “local” plates of cells during the 12 min of field activation produced conspicuous cell death (reduction of viable cells by about 50%) with comparable diminishments of cell numbers in the non-local plates of cells within 24 hr but only if both loci separated by either 3 m or 1.7 km had shared the “excess correlation” magnetic field sequence. The non-local effect did not occur if the magnetic fields had not been present. Higher or lower concentrations of peroxide or concentrations that eliminated all of the cells or very few cells in the local dishes were associated with no significant diminishment of non-local cell growth. The data indicate that there must be a critical number of cells remaining viable following the local chemical reaction for the excess correlation to be manifested in the non-local cells. We suggest that this specific spatial-temporal pattern of fields generated within the paired toroidal geometries promotes transposition of virtual chemical reactions as an information field. Calculations of the energy available per cell and per volume of the quantity of reactants injected into the local space from the intensity of the changing velocity toroidal magnetic field support previous measurements and derivations that the units of information transposition may involve discrete quantities that represent equivalents of photons, electrons and protons.展开更多
Due to its difficulty in early diagnosis and lack of sensitivity to chemotherapy and radiotherapy,renal cell carcinoma(RCC)remains to be a frequent cause of cancer-related death.Here,we probed into new targets for its ...Due to its difficulty in early diagnosis and lack of sensitivity to chemotherapy and radiotherapy,renal cell carcinoma(RCC)remains to be a frequent cause of cancer-related death.Here,we probed into new targets for its early diagnosis and treatment for RCC.microRNA(miRNA)data of M2-EVs and RCC were searched on the Gene Expression Omnibus database,followed by the prediction of the potential downstream target.Expression of target genes was measured via RT-qPCR and Western blot,respectively.M2 macrophage was obtained viaflow cytometry with M2-EVs extracted.The binding ability of miR-342-3p to NEDD4L and to CEP55 ubiquitination was studied with their roles in the physical abilities of RCC cells assayed.Subcutaneous tumor-bearing mouse models and lung metastasis models were prepared to observe in vivo role of target genes.M2-EVs induced RCC growth and metastasis.miR-342-3p showed high expression in both M2-EVs and RCC cells.M2-EVs carrying miR-342-3p promoted RCC cell abilities to proliferate,invade and migrate.In RCC cells,M2-EV-derived miR-342-3p could specifically bind to NEDD4L and consequently elevate CEP55 protein expression via suppressing NEDD4L,thereby exerting tumor-promoting effects.CEP55 could be degraded by ubiquitination under the function of NEDD4L,and miR-342-3p delivered by M2-EVs facilitated the RCC occurrence and development by activating the PI3K/AKT/mTOR signaling pathway.In conclusion,M2-EVs promote RCC growth and metastasis by delivering miR-342-3p to suppress NEDD4L and subsequently inhibit CEP55 ubiquitination and degradation via activation of the PI3K/AKT/mTOR signaling pathway,strongly driving the proliferative,migratory and invasive of RCC cells.展开更多
Objective To investigate the effects of 14-3-3 protein overexpression on the 1-methyl-4-phenylpyridinium (MPP^+) induced pheochromocytoma (PC12) cell death and the potential mechanisms. Methods pcDNA3.1(+)-14-...Objective To investigate the effects of 14-3-3 protein overexpression on the 1-methyl-4-phenylpyridinium (MPP^+) induced pheochromocytoma (PC12) cell death and the potential mechanisms. Methods pcDNA3.1(+)-14-3-3 plasmids, which could be expressed in mammalian cell, were constructed and transfected into PC 12 cells with Lipofectamine 2000. The expression of 14-3-3 protein, Bcl-2 protein, and BAD protein were determined by western blot. 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, microplate reader, and flow cytometric analysis were used to measure cell viability, the caspase activity, and apoptotic ratio respectively. Results (1) The expression of 14-3-3 protein increased significantly three weeks after pcDNA3.1(+)-14-3-3 plasmids transfected into PC 12 cells. (2) MPP^+ caused a decrease of cell viability in a dose-dependent manner. At 100μmol/L MPP^+, cell viability reduced approximately 50%. (3) The caspase activity increased along with the MPP^+ concentrations rising and reached its maximum value (0.34 μmol/mg protein) at 100 μmol/L MPP*. However caspase activity decreased significantly when the MPP^+ concentration exceeded 100 μmol/L. (4) Overexpression of 14-3-3 protein decreased the apoptosis ratio of PC 12 cells treated with 100μmol/L MPP^+ from 26.5% to 8.6%. (5) Bcl-2 protein tended to decrease but BAD protein tended to increase after treatment of PC 12 cells with 100 μmol/L MPP^+. Overexpression of 14-3-3 protein significantly increased the cellular level of Bcl-2 protein and decreased that of BAD protein. Conclusion Overexpression of 14-3-3 protein may reduce MPP^+-induced apoptotic cell death in PC12 cells by up-regulating the Bcl-2 expression and down-regulating the BAD expression. These results may provide a promising target for treatment of Parkinson's disease.展开更多
Objective To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP^+) and to explore the potential mech...Objective To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP^+) and to explore the potential mechanisms. Methods The viability and apoptosis of PC 12 cells were determinded by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4′,6′-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phospholylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2). Results The cell viability decreased and the number of apoptotic cells increased dramatically in MPP^+ group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP^+- treated PC 12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK 1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC 12 cells induced by HPP. Conclusion HPP protects PC 12 cells against MPP+ toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.展开更多
The perovskite-type oxide solid solution Ba0.98Ce0.8Tm0.2O3-α was prepared by high temperature solid-state reaction and its single phase character was confirmed by X-ray diffraction. The conduction property of the sa...The perovskite-type oxide solid solution Ba0.98Ce0.8Tm0.2O3-α was prepared by high temperature solid-state reaction and its single phase character was confirmed by X-ray diffraction. The conduction property of the sample was investigated by alternating current impedance spectroscopy and gas concentration cell methods under different gases atmospheres in the temperature range of 500-900 ℃. The performance of the hydrogen-air fuel cell using the sample as solid electrolyte was measured. In wet hydrogen, the sample is a pure protonic conductor with the protonic transport number of 1 in the range of 500-600 ℃, a mixed conductor of proton and electron with the protonic transport number of 0.945-0.933 above 600 ℃. In wet air, the sample is a mixed conductor of proton, oxide ion, and electronic hole. The protonic transport numbers are 0.010-0.021, and the oxide ionic transport numbers are 0.471-0.382. In hydrogen-air fuel cell, the sample is a mixed conductor of proton, oxide ion and electron, the ionic transport numbers are 0.942 0.885. The fuel cell using Ba0.98Ce0.8Tm0.2O3-α as solid electrolyte can work stably. At 900 ℃, the maximum power output density is 110,2 mW/cm2, which is higher than that of our previous cell using Ba0.98Ce0.8Tm0.2O3-α (x〈≤1, RE=Y, Eu, Ho) as solid electrolyte.展开更多
The conventional Ni cermet anode suffers from severe carbon deposition and sulfur poisoning when fossil fuels are used. Alternative anode materials are desired for high performance hydrocarbon fuel solid oxide fuel ce...The conventional Ni cermet anode suffers from severe carbon deposition and sulfur poisoning when fossil fuels are used. Alternative anode materials are desired for high performance hydrocarbon fuel solid oxide fuel cells (SOFCs). We report the rational design of a very active Ni doped La0.6Sr0.4FeO3‐δ(LSFN) electrode for hydrocarbon fuel SOFCs. Homogeneously dispersed Ni‐Fe alloy nanoparticles were in situ extruded onto the surface of the LSFN particles during the operation of the cell. Sym‐metric SOFC single cells were prepared by impregnating a LSFN precursor solution onto a YSZ (yt‐tria stabilized zirconia) monolithic cell with a subsequent heat treatment. The open circuit voltage of the LSFN symmetric cell reached 1.18 and 1.0 V in humidified C3H8 and CH4 at 750??, respective‐ly. The peak power densities of the cells were 400 and 230 mW/cm2 in humidified C3H8 and CH4, respectively. The electrode showed good stability in long term testing, which revealed LSFN has good catalytic activity for hydrocarbon fuel oxidation.展开更多
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three all...As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.展开更多
Objective:To evaluate anti-diabetic effect of Caulrpa kntillifera(C.lentillifera).Methods:The inhibitory effect of C.lentillifera extract on dipeptidyl peptidase-IV and a-glucosidase enzyme was measured in a cell free...Objective:To evaluate anti-diabetic effect of Caulrpa kntillifera(C.lentillifera).Methods:The inhibitory effect of C.lentillifera extract on dipeptidyl peptidase-IV and a-glucosidase enzyme was measured in a cell free system.Then,interleukin-1βand interferon-γinduced cell death and insulin secretion were measured in rat insulinoma(RIN)cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and ELISA kit,respectively.Glucose uptake and glucose transporter expression were measured by fluorometry and western blotting,using 3T3-Ll adipocytes.Results:C.lentillifera extract significantly decreased dipeptidyl peptidase-IV and a-glucosidase enzyme activities,and effectively inhibited cell death and iNOS expression in interleukin-1βand interfcron-γinduced RIK cells.Furthermore,C.lntillifera extract significantly enhanced insulin secretion in RTN cells and glucose transporter expression and glucose uptake in 3T3-L1adipocytes.Conclusions:Thus,our results suggest that C.lentillifera could be used as a potential antidiabetic agenl.展开更多
AIM: To investigate the biological function of 14-3-3σ protein and to look for proteins that interact with 14-3-3σ protein in colon cancer stem cells. METHODS: Reverse transcription polymerase chain reaction was per...AIM: To investigate the biological function of 14-3-3σ protein and to look for proteins that interact with 14-3-3σ protein in colon cancer stem cells. METHODS: Reverse transcription polymerase chain reaction was performed to amplify the 14-3-3σ gene from the mRNA of colon cancer stem cells. The gene was then cloned into the pGEM-T vector. After being sequenced, the target gene 14-3-3σ was cut from the pGEM-T vector and cloned into the pGBKT7 yeast expression plasmid. Then, the bait plasmid pGBKT7-14-3-3σ was transformed into the yeast strain AH109. After the expression of the pGBKT7-14-3-3σ fusion protein in the AH109 yeast strain was accomplished, a yeast two-hybrid screening assay was performed by mating AH109 with Y187 that contained a HeLa cDNA library plasmid. The interaction between the 14-3-3σ protein and the proteins obtained from positive colonies was further confirmed by repeating the yeast two-hybridscreen. After extracting and sequencing the plasmids from the positive colonies, we performed a bioinformatics analysis. A coimmunoprecipitation assay was performed to confirm the interaction between 14-3-3σ and the proteins obtained from the positive colonies. Finally, we constructed 14-3-3σ and potassium channel modulatory factor 1 (KCMF1) siRNA expression plasmids and transfected them into colon cancer stem cells. RESULTS: The bait plasmid pGBKT7-14-3-3σ was constructed successfully, and the 14-3-3σ protein had no toxic or autonomous activation effect on the yeast. Nineteen true-positive colonies were selected and sequenced, and their full-length sequences were obtained. We searched for homologous DNA sequences for these sequences from GenBank. Among the positive colonies, four coding genes with known functions were obtained, including KCMF1 , quinone oxidore-ductase (NQO2 ), hydroxyisobutyrate dehydrogenase (HIBADH ) and 14-3-3σ . For the subsequent coimmu-noprecipitation assay, the plasmids PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH were successfully constructed, and the sequences were further confirmed by DNA sequencing. The Fugene 6 reagent was used to transfect the plasmids, and fluorescence-activated cell sorting analysis showed the transfection efficiency was 97.8% after 48 h. The HEK 293FT cells showed the stable expression of the PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH plasmids. After anti-Myc antibody immunoprecipitation with Myc-KCMF1, Myc-NQO2 and Myc-HIBADH from cell lysates, the presence of Flag-14-3-3σ protein in the immuno-precipitated complex was determined by western blot analysis. The knock-down expression of the 14-3-3σ and KCMF1 proteins significantly inhibited cell proliferation and colony formation of SW1116csc. CONCLUSION: Genes of the proteins that interactedwith 14-3-3σ were successfully screened from a HeLa cDNA library. KCMF1 and 14-3-3σ protein may affect the proliferation and colony formation of human colon cancer stem cells.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82271397(to MG),82001293(to MG),82171355(to RX),81971295(to RX)and 81671189(to RX)。
文摘Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.
基金Supported by the National Natural Science Foundation of China,No.81900743Heilongjiang Province Outstanding Young Medical Talents Training Grant Project,China,No.HYD2020YQ0007.
文摘BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are unknown.In this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation.AIM To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage.METHODS BMSC-exo were isolated from mouse BMSC media.This was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro analyses.The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of mice.RESULTS Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery.MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation.Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases.Furthermore,we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA.CONCLUSION We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain.
基金supported by the National Natural Science Foundation of China(32272849)the National Key R&D Program of China(2021YFF1000602)the earmarked fund for CARS-35-PIG。
文摘Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landrace sows was significantly higher than that of low-yielding sows.However,the functions of miR-24-3p on GCs are unclear.In this study,using flow cytometry,5-ethynyl-2′-de-oxyuridine(EdU)staining,and cell count,we showed that miR-24-3p promoted the proliferation of GCs increasing the proportion of cells in the S phase and upregulating the expression of cell cycle genes,moreover,miR-24-3p inhibited GC apoptosis.Mechanistically,on-line prediction,bioinformatics analysis,a luciferase reporter assay,RT-qPCR,and Western blot results showed that the target gene of miR-24-3p in proliferation and apoptosis is cyclin-dependent kinase inhibitor 1B(P27/CDKN1B).Furthermore,the effect of miR-24-3p on GC proliferation and apoptosis was attenuated by P27 overexpression.These findings suggest that miR-24-3p regulates the physiological functions of GCs.
文摘Background:Osteosarcoma(OS),recognized as the predominant malignant tumor originating from bones,necessitates an in-depth comprehension of its intrinsic mechanisms to pinpoint novel therapeutic targets and enhance treatment methodologies.The role of fat mass and obesity-associated(FTO)in OS,particularly its correlation with malignant traits,and the fundamental mechanism,remains to be elucidated.Materials and Methods:1.The FTO expression and survival rate in tumors were analyzed.2.FTO in OS cell lines was quantified utilizing western blot and PCR.3.FTO was upregulated and downregulated separately in MG63.4.The impact of FTO on the proliferation and migration of OS cells was evaluated using CCK-8,colony formation,wound healing,and Transwell assays.5.The expression of miR-150-5p in OS cells-derived exosomes was identified.6.The binding of miR-150-5p to FTO was predicted by TargetScan and confirmed by luciferase reporter assay.7.The impact of exosome miR-150-5p on the proliferation and migration of OS cells was investigated.Results:The expression of FTO was higher in OS tissues compared to normal tissues correlating with a worse survival rate.Furthermore,the downregulation of FTO significantly impeded the growth and metastasis of OS cells.Additionally,miR-150-5p,which was downregulated in both OS cells and their derived exosomes,was found to bind to the 3′-UTR of FTO through dual luciferase experiments.Exosomal miR-150-5p was found to decrease the expression of FTO and inhibit cell viability.Conclusions:We identified elevated levels of FTO in OS,which may be attributed to insufficient miR-150-5p levels in both the cells and exosomes.It suggests that the dysregulation of miR-150-5p and its interaction with FTO could potentially promote the development of OS.
基金supported by the National Natural Science Foundation of China[Grant Number:81972803]。
文摘Objective To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer(CRC).Methods The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR,respectively.Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p.The protein expressions of p53 and unc-51 like kinase 2(ULK2)in CRC cells were detected by western blot.Flow cytometry was used to detect cell cycle and apoptosis.Cell proliferation was measured by CCK8 and EdU assay.Results The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage.CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner,and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine.Moreover,ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues.Interestingly,ULK2 inhibited CRC cell proliferation in a p53-dependent manner.Furthermore,exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells.Conclusion Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC,which may offer promising targets for CRC prevention and therapy.
文摘Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) is a bacterial pathogen of tomato and of the model plants Arabidopsis and Nicotiana benthamiana (N. benthamiana). Like numerous Gram-negative bacterial pathogens of animals and plants, Pst DC3000 exploits the conserved type III secretion system (TTSS) to deliver multiple virulence effectors directly into the host cells. Type III effectors (T3Es) collectively participate in causing disease, by mechanisms that are not well clarity. Elucidating the virulence function of individual effector is fundamental for understanding bacterial infection of plants. Here, we focused on studying one of these effectors, HopAA1-1, and analyzed its potential function and subcellular localization in N. benthamiana. Using an Agrobacterium-mediated transient expression system, we found that HopAA1-1 can trigger domain-dependent cell death in N. benthamiana. The observation using confocal microscopy showed that the YFP-tagged HopAA1-1 localizes to diverse cellular components containing nucleus, cytoplasm and cell membrane, which was demonstrated through immunoblot analysis of membrane fractionation and nuclear separation. Enforced HopAA1-1 subcellular localization, by tagging with a nuclear localization sequence (NLS) or a nuclear export sequence (NES), shows that HopAA1-1-induced cell death in N. benthamiana is suppressed in the nucleus but enhanced in the cytoplasm. Our research is lay a foundation for revealed the molecular pathogenesis of Pseudomonas syringae pv. tomato.
基金Changshu Science and Technology Plan(Social Development)Project(No.CS202130)Key Project of Changshu No.2 People’s Hospital(No.CSEY2021007)。
文摘Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.
基金Supported by Youth Fund Project of Zhaoqing University(QZ202235)Zhaoqing Science and Technology Plan Project(2022040311011).
文摘[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavonoid glycosides were isolated and purified from the ethanol alcoholic extract of the roots of Liliaceae plant Chlorophytum comosum by silica gel column chromatography,macroporous resin column chromatography,Sephadex LH-20,and reverse column chromatography(ODS).The inhibitory activity of flavonoid glycosides on human nasopharyngeal carcinoma cells was analyzed by CCK-8 method,and the potential mechanism was preliminarily analyzed by molecular docking.[Results]Two flavonoid glycosides were identified as isovitexin 2″-0-rhamnoside and 7-2″-di-O-β-glucopyranosylisovitexin.Two flavonoid glycosides showed promising inhibitory effect on human nasopharyngeal carcinoma cell line 5-8F,with IC_(50) values of 24.8 and 27.5μmol/L,respectively.Molecular docking results showed that the potential targets of two flavonoid glycosides include CyclinD1,Bcl-2β-Catenin,ILK,TGF-β,in addition,two glycosides showed higher predicted binding affinity towards CyclinD1,which verifies the cytotoxicity of the two compounds on human nasopharyngeal carcinoma cell line 5-8F in vitro.[Conclusions]Two flavonoid glycosides are the active molecules in Chlorophytum comosum that can inhibit the proliferation of human nasopharyngeal carcinoma cells,and have the potential to be used in the research and development of anti nasopharyngeal carcinoma drugs.
文摘A complex programmable logical device (CPLD) based on conventional embedded Flash memory process with 72 macro cells is studied in the paper. Compared with the Flash cell array technology employed by foreign companies, this architecture exhibiting insystem reconfiguration and rapid response was manufactured by low cost fabrication process. The device architecture and critical cell design are also analyzed in detail in the paper. The CPLD was designed by full-custom ASIC technology and manufactured by 0.35 pm 3P3M Flash process with 72 macro cells and 5 V voltage supply. The measurement results indicate that the devices are able to operate above the frequency of 66.7 MHz with the pin delay less than 10 ns.
文摘In multiple experiments plates of melanoma cells separated by either 3 m or 1.7 km were placed in the centers of toroids. A specific protocol of changing, angular velocity, pulsed magnetic fields that has been shown to produce excess correlation in photon durations and shift in proton concentrations (pH) in spring water were generated around both plates of cells. Serial injections of 50 μL of standard concentrations of hydrogen peroxide into the “local” plates of cells during the 12 min of field activation produced conspicuous cell death (reduction of viable cells by about 50%) with comparable diminishments of cell numbers in the non-local plates of cells within 24 hr but only if both loci separated by either 3 m or 1.7 km had shared the “excess correlation” magnetic field sequence. The non-local effect did not occur if the magnetic fields had not been present. Higher or lower concentrations of peroxide or concentrations that eliminated all of the cells or very few cells in the local dishes were associated with no significant diminishment of non-local cell growth. The data indicate that there must be a critical number of cells remaining viable following the local chemical reaction for the excess correlation to be manifested in the non-local cells. We suggest that this specific spatial-temporal pattern of fields generated within the paired toroidal geometries promotes transposition of virtual chemical reactions as an information field. Calculations of the energy available per cell and per volume of the quantity of reactants injected into the local space from the intensity of the changing velocity toroidal magnetic field support previous measurements and derivations that the units of information transposition may involve discrete quantities that represent equivalents of photons, electrons and protons.
基金supported by the Science and Technology Department of Sichuan Province(2015SZ0117,2019YJ0701,and 2021YJ0239).
文摘Due to its difficulty in early diagnosis and lack of sensitivity to chemotherapy and radiotherapy,renal cell carcinoma(RCC)remains to be a frequent cause of cancer-related death.Here,we probed into new targets for its early diagnosis and treatment for RCC.microRNA(miRNA)data of M2-EVs and RCC were searched on the Gene Expression Omnibus database,followed by the prediction of the potential downstream target.Expression of target genes was measured via RT-qPCR and Western blot,respectively.M2 macrophage was obtained viaflow cytometry with M2-EVs extracted.The binding ability of miR-342-3p to NEDD4L and to CEP55 ubiquitination was studied with their roles in the physical abilities of RCC cells assayed.Subcutaneous tumor-bearing mouse models and lung metastasis models were prepared to observe in vivo role of target genes.M2-EVs induced RCC growth and metastasis.miR-342-3p showed high expression in both M2-EVs and RCC cells.M2-EVs carrying miR-342-3p promoted RCC cell abilities to proliferate,invade and migrate.In RCC cells,M2-EV-derived miR-342-3p could specifically bind to NEDD4L and consequently elevate CEP55 protein expression via suppressing NEDD4L,thereby exerting tumor-promoting effects.CEP55 could be degraded by ubiquitination under the function of NEDD4L,and miR-342-3p delivered by M2-EVs facilitated the RCC occurrence and development by activating the PI3K/AKT/mTOR signaling pathway.In conclusion,M2-EVs promote RCC growth and metastasis by delivering miR-342-3p to suppress NEDD4L and subsequently inhibit CEP55 ubiquitination and degradation via activation of the PI3K/AKT/mTOR signaling pathway,strongly driving the proliferative,migratory and invasive of RCC cells.
基金supported by National Natural Science Foundation of China(No:30570627).
文摘Objective To investigate the effects of 14-3-3 protein overexpression on the 1-methyl-4-phenylpyridinium (MPP^+) induced pheochromocytoma (PC12) cell death and the potential mechanisms. Methods pcDNA3.1(+)-14-3-3 plasmids, which could be expressed in mammalian cell, were constructed and transfected into PC 12 cells with Lipofectamine 2000. The expression of 14-3-3 protein, Bcl-2 protein, and BAD protein were determined by western blot. 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, microplate reader, and flow cytometric analysis were used to measure cell viability, the caspase activity, and apoptotic ratio respectively. Results (1) The expression of 14-3-3 protein increased significantly three weeks after pcDNA3.1(+)-14-3-3 plasmids transfected into PC 12 cells. (2) MPP^+ caused a decrease of cell viability in a dose-dependent manner. At 100μmol/L MPP^+, cell viability reduced approximately 50%. (3) The caspase activity increased along with the MPP^+ concentrations rising and reached its maximum value (0.34 μmol/mg protein) at 100 μmol/L MPP*. However caspase activity decreased significantly when the MPP^+ concentration exceeded 100 μmol/L. (4) Overexpression of 14-3-3 protein decreased the apoptosis ratio of PC 12 cells treated with 100μmol/L MPP^+ from 26.5% to 8.6%. (5) Bcl-2 protein tended to decrease but BAD protein tended to increase after treatment of PC 12 cells with 100 μmol/L MPP^+. Overexpression of 14-3-3 protein significantly increased the cellular level of Bcl-2 protein and decreased that of BAD protein. Conclusion Overexpression of 14-3-3 protein may reduce MPP^+-induced apoptotic cell death in PC12 cells by up-regulating the Bcl-2 expression and down-regulating the BAD expression. These results may provide a promising target for treatment of Parkinson's disease.
基金the National Natural Science Foundation of China (No. 30570627)
文摘Objective To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP^+) and to explore the potential mechanisms. Methods The viability and apoptosis of PC 12 cells were determinded by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4′,6′-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phospholylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2). Results The cell viability decreased and the number of apoptotic cells increased dramatically in MPP^+ group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP^+- treated PC 12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK 1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC 12 cells induced by HPP. Conclusion HPP protects PC 12 cells against MPP+ toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.
文摘The perovskite-type oxide solid solution Ba0.98Ce0.8Tm0.2O3-α was prepared by high temperature solid-state reaction and its single phase character was confirmed by X-ray diffraction. The conduction property of the sample was investigated by alternating current impedance spectroscopy and gas concentration cell methods under different gases atmospheres in the temperature range of 500-900 ℃. The performance of the hydrogen-air fuel cell using the sample as solid electrolyte was measured. In wet hydrogen, the sample is a pure protonic conductor with the protonic transport number of 1 in the range of 500-600 ℃, a mixed conductor of proton and electron with the protonic transport number of 0.945-0.933 above 600 ℃. In wet air, the sample is a mixed conductor of proton, oxide ion, and electronic hole. The protonic transport numbers are 0.010-0.021, and the oxide ionic transport numbers are 0.471-0.382. In hydrogen-air fuel cell, the sample is a mixed conductor of proton, oxide ion and electron, the ionic transport numbers are 0.942 0.885. The fuel cell using Ba0.98Ce0.8Tm0.2O3-α as solid electrolyte can work stably. At 900 ℃, the maximum power output density is 110,2 mW/cm2, which is higher than that of our previous cell using Ba0.98Ce0.8Tm0.2O3-α (x〈≤1, RE=Y, Eu, Ho) as solid electrolyte.
基金supported by the National Natural Science Foundation of China (51372271,51172275)the National Basic Research Program of China (973 Program,2012CB215402)~~
文摘The conventional Ni cermet anode suffers from severe carbon deposition and sulfur poisoning when fossil fuels are used. Alternative anode materials are desired for high performance hydrocarbon fuel solid oxide fuel cells (SOFCs). We report the rational design of a very active Ni doped La0.6Sr0.4FeO3‐δ(LSFN) electrode for hydrocarbon fuel SOFCs. Homogeneously dispersed Ni‐Fe alloy nanoparticles were in situ extruded onto the surface of the LSFN particles during the operation of the cell. Sym‐metric SOFC single cells were prepared by impregnating a LSFN precursor solution onto a YSZ (yt‐tria stabilized zirconia) monolithic cell with a subsequent heat treatment. The open circuit voltage of the LSFN symmetric cell reached 1.18 and 1.0 V in humidified C3H8 and CH4 at 750??, respective‐ly. The peak power densities of the cells were 400 and 230 mW/cm2 in humidified C3H8 and CH4, respectively. The electrode showed good stability in long term testing, which revealed LSFN has good catalytic activity for hydrocarbon fuel oxidation.
文摘As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects.
基金Supported by the Ministry of Education.Science and Technology (Grant No.2012RTAL2009172)
文摘Objective:To evaluate anti-diabetic effect of Caulrpa kntillifera(C.lentillifera).Methods:The inhibitory effect of C.lentillifera extract on dipeptidyl peptidase-IV and a-glucosidase enzyme was measured in a cell free system.Then,interleukin-1βand interferon-γinduced cell death and insulin secretion were measured in rat insulinoma(RIN)cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and ELISA kit,respectively.Glucose uptake and glucose transporter expression were measured by fluorometry and western blotting,using 3T3-Ll adipocytes.Results:C.lentillifera extract significantly decreased dipeptidyl peptidase-IV and a-glucosidase enzyme activities,and effectively inhibited cell death and iNOS expression in interleukin-1βand interfcron-γinduced RIK cells.Furthermore,C.lntillifera extract significantly enhanced insulin secretion in RTN cells and glucose transporter expression and glucose uptake in 3T3-L1adipocytes.Conclusions:Thus,our results suggest that C.lentillifera could be used as a potential antidiabetic agenl.
基金Supported by The Medical Guidance Projects of Shanghai Science Committee,No.10411961800National Natural Science Foundation of China,No.81101617
文摘AIM: To investigate the biological function of 14-3-3σ protein and to look for proteins that interact with 14-3-3σ protein in colon cancer stem cells. METHODS: Reverse transcription polymerase chain reaction was performed to amplify the 14-3-3σ gene from the mRNA of colon cancer stem cells. The gene was then cloned into the pGEM-T vector. After being sequenced, the target gene 14-3-3σ was cut from the pGEM-T vector and cloned into the pGBKT7 yeast expression plasmid. Then, the bait plasmid pGBKT7-14-3-3σ was transformed into the yeast strain AH109. After the expression of the pGBKT7-14-3-3σ fusion protein in the AH109 yeast strain was accomplished, a yeast two-hybrid screening assay was performed by mating AH109 with Y187 that contained a HeLa cDNA library plasmid. The interaction between the 14-3-3σ protein and the proteins obtained from positive colonies was further confirmed by repeating the yeast two-hybridscreen. After extracting and sequencing the plasmids from the positive colonies, we performed a bioinformatics analysis. A coimmunoprecipitation assay was performed to confirm the interaction between 14-3-3σ and the proteins obtained from the positive colonies. Finally, we constructed 14-3-3σ and potassium channel modulatory factor 1 (KCMF1) siRNA expression plasmids and transfected them into colon cancer stem cells. RESULTS: The bait plasmid pGBKT7-14-3-3σ was constructed successfully, and the 14-3-3σ protein had no toxic or autonomous activation effect on the yeast. Nineteen true-positive colonies were selected and sequenced, and their full-length sequences were obtained. We searched for homologous DNA sequences for these sequences from GenBank. Among the positive colonies, four coding genes with known functions were obtained, including KCMF1 , quinone oxidore-ductase (NQO2 ), hydroxyisobutyrate dehydrogenase (HIBADH ) and 14-3-3σ . For the subsequent coimmu-noprecipitation assay, the plasmids PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH were successfully constructed, and the sequences were further confirmed by DNA sequencing. The Fugene 6 reagent was used to transfect the plasmids, and fluorescence-activated cell sorting analysis showed the transfection efficiency was 97.8% after 48 h. The HEK 293FT cells showed the stable expression of the PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH plasmids. After anti-Myc antibody immunoprecipitation with Myc-KCMF1, Myc-NQO2 and Myc-HIBADH from cell lysates, the presence of Flag-14-3-3σ protein in the immuno-precipitated complex was determined by western blot analysis. The knock-down expression of the 14-3-3σ and KCMF1 proteins significantly inhibited cell proliferation and colony formation of SW1116csc. CONCLUSION: Genes of the proteins that interactedwith 14-3-3σ were successfully screened from a HeLa cDNA library. KCMF1 and 14-3-3σ protein may affect the proliferation and colony formation of human colon cancer stem cells.