The inferior rate capability and poor cycle stability of the present Li–O2 batteries are still critical obstacles for practice applications. Configuring novel and integrated air electrode materials ...with unique structure and tunable chemical compositions is one of the efficient strategies to solve these bottleneck problems. Herein, a novel strategy for synthesis of 3D porous N‐doped graphene aerogels (NPGAs) with frameworks constructed by interconnected nanocages with the aid of polystyrene sphere@polydopamine is reported. The interconnected nanocages as the basic building unit of graphene sheets are assembled inside the skeletons of 3D graphene aerogels, leading to the 3D NPGA with well‐developed interconnected channels and the full exposure of electrochemically active sites. Benefiting from such an unique structure, the as‐made NPGA delivers a high specific capacity, an excellent rate capacity of 5978 mA h g−1 at 3.2 A g−1, and long cycle stability, especially at a large current density (54 cycles at 1 A g−1), indicative of boosted rate capability and cycle life as air electrodes for Li–O2 batteries. More importantly, based on the total mass of C+Li2O2, a gravimetric energy density of 2400 W h kg−1 for the NPGA–O2//Li cell is delivered at a power density of 1300 W kg−1.
3D porous N‐doped graphene frameworks constructed by interconnected nanocages are configured with the aid of polystyrene sphere@polydopamine. The interconnected nanocages as the basic building unit of graphene sheets are assembled inside skeletons of graphene aerogels, resulting in well‐developed interconnected channels and full exposure of heteroatom sites, thus help to boost the rate capability and cycle life for Li–O2 batteries.
Long non-coding RNAs (lncRNAs) play critical functions in various cancers. Firre intergenic repeating RNA element (FIRRE), a lncRNA located in the nucleus, was overexpressed in colorectal cancer ...(CRC). However, the detailed mechanism of FIRRE in CRC remains elusive. Results of RNA sequence and qPCR illustrated overexpression of FIRRE in CRC cell lines and tissues. The aberrant expression of FIRRE was correlated with the migration, invasion, and proliferation in cell lines. In accordance, it was also associated with lymphatic metastasis and distant metastasis in patients with CRC. FIRRE was identified to physically interact with Polypyrimidine tract-binding protein (PTBP1) by RNA pull-down and RNA immunoprecipitation (RIP). Overexpression of FIRRE induced the translocation of PTBP1 from nucleus to cytoplasm, which was displayed by immunofluorescence and western blot. In turn, delocalization of FIRRE from nucleus to cytoplasm is observed after the loss of PTBP1. The RNA-protein complex in the cytoplasm directly bound to BECN1 mRNA, and the binding site was at the 3' end of the mRNA. Cells with FIRRE and PTBP1 depletion alone or in combination were treated by Actinomycin D (ACD). Results of qPCR showed FIRRE stabilized BECN1 mRNA in a PTBP1-medieated manner. In addition, FIRRE contributed to autophagy activity. These findings indicate FIRRE acts as an oncogenic factor in CRC, which induces tumor development through stabilizing BECN1 mRNA and facilitating autophagy in a PTBP1-mediated manner.
Graphene-incorporated nitrogen-rich carbon composite with nitrogen content of ca. 10wt.% has been synthesized by an effective yet simple hydrothermal reaction of glucosamine in the presence of ...graphene oxide (GO). The nitrogen content of carbon composite is nearly twice as high as that of hydrothermal carbon without graphene. GO is favorable for the high nitrogen doping in the carbon composite by the reaction between the glucosamine-released ammonia and GO. The hydrothermal carbon composite is further activated by KOH, and graphene in the activated carbon composite demonstrates a positive effect of increasing specific surface area, pore volume and electrical conductivity, resulting in superior electrochemical performance. The activated carbon composite with higher specific surface area and micropore volume possesses higher specific capacitance with a value of 300Fg−1 at 0.1Ag−1 in 6M KOH aqueous solution in the two electrode cell. Larger mesopore volume and higher conductivity of the activated carbon composite will provide fast ion and electron transfer, thus leading to higher rate capacity with a capacitance retention of 76% at 8Ag−1 in comparison to the activated hydrothermal carbon without graphene.
MicroRNA plays a pivotal role in various human cancers, especially in human gastric cancer. In the present study, we evaluated the effect of microRNA-21 (miR-21) on the gastric cancer cell ...proliferation, migration, apoptosis and the related signaling cascades. Here, we showed that down-regulation of miR-21 markedly reduced gastric cancer cell proliferation (AGS and NCI-N87 cells) in a time dependent manner. Moreover, our findings revealed that silencing miR-21 dramatically blocked gastric cancer cell migration and movement, which might be related to down-regulation of vimentin expression. We also found that down-regulation of miR-21 promoted cell apoptosis and repressed cell cycle progression. Further investigation showed that down-regulation of miR-21 significantly increased phosphatase and tensin homolog (PTEN) protein expression level, but not transcription level (mRNA level), which in turn decreased Akt phosphorylation at Thr308 and Ser473. Collectively, our results uncover that miR-21 targets PTEN/Akt signaling pathway and regulates cell proliferation, migration and apoptosis in human gastric cancer cells. Our findings may provide a therapeutic target for treatment of human gastric cancer.
In seed plants, the ovule is the precursor to the seed. The process of ovule development and differentiation is regulated by multiple factors, including starch metabolism and endogenous hormones. ...Castanea henryi produces nuts with high nutritional value. However, the high proportion of empty buds restricts the commercial use of the tree. Previous studies have shown that the empty bud phenotype is closely related to ovule abortion. If none of the ovules in the ovary expand rapidly and develop in 7-8 weeks after pollination, an empty bud will form. Therefore, we studied the development and molecular mechanisms underlying single seed formation in C. henryi.
We found that 49 days after pollination (DAP) is a critical period for the formation of fertile and abortive ovules. The morphology and starch distribution of the fertile and abortive ovules differed significantly at 49 DAP. The fertile ovules were smooth and round in appearance, with a large amount of starch. In contrast, abortive ovules were smaller with only a small amount of starch. The embryo sac of the abortive ovule proceeded to develop abnormally, and the entire ovule lacked starch. We identified 37 candidate genes involved in metabolism with potential roles in the regulation of starch levels. Three ADP-glucose pyrophosphorylase (AGPase) genes, one granule-bound starch synthase (GBSS) gene, and two beta-amylase genes could affect starch accumulation. The levels of auxin, cytokinins, gibberellins, and jasmonic acid in fertile ovules were higher than those in abortive ovules. In addition, the levels of endogenous abscisic acid and salicylic acid in abortive ovules were higher than those in fertile ovules of the same age, consistent with the expression patterns of genes related to the synthesis of abscisic and salicylic acid and signal transduction. We identified and mapped the differentially expressed genes associated with hormone synthesis and signal transduction.
These results improve our general understanding of the molecular mechanisms underlying single seed development in C. henryi and the phenomenon of empty buds, providing directions for future research.
Castanea henryi
is a monoecious woody food tree species whose yield and industrialization potential are limited by its low female-to-male flower ratio. Here, the male flowers on the male ...inflorescence of
C. henryi
were converted to female flowers by triple applications of exogenous cytokinin (CK) (N-(2-chloro-4-pyridyl)-N’-phenylurea, CPPU). To study the role of exogenous CK in flower sex determination, cytological and transcriptomic analyses were performed on samples from the five stages after CK treatment. Cytological analysis showed that stage 3 (nine days after the last CK treatment) was the critical stage in the differential development of the pistil primordium and stamen primordium. On this basis, one key module and two modules with significant positive correlations with stage 3 were identified by weighted gene co-expression network analysis (WGCNA), combined with transcriptome data. The CK and GA biosynthesis- and signaling-related genes, three transcription factor (TF) families, and 11 floral organ identity genes were identified in the related modules. In particular, the TFs
WRKY47
,
ERF021
, and
MYB4
, and floral organ identity genes
AGL11
/
15
,
DEF
, and
SEP1
with large differences are considered to be critical regulators of sex determination in
C. henryi
. Based on these results, a genetic regulatory network for exogenous CK in the sex determination of flowers in
C. henryi
is proposed. This study contributes to the understanding of the role of CK in the sex regulation of flowers and provides new insights into the regulatory network of sex determination in
C. henryi.
The aim of this study was to investigate the effect of quercetin on hepatic fibrosis, a characteristic response to acute or chronic liver injury. Mice were randomized to bile duct ligation (BDL) or ...carbon tetrachloride (CCl
) cirrhosis models. Quercetin (100 mg/kg or 200 mg/kg daily) was administered by gavage for 2 or 4 weeks. Liver tissue and blood samples were collected for histological and molecular analysis. The results of our experiments showed that quercetin reduced BDL or CCl
liver fibrosis, inhibited extracellular matrix formation, and regulated matrix metallopeptidase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1. Quercetin attenuated liver damage by suppressing the TGF-β1/Smads signaling pathway and activating the PI3K/Akt signaling pathway to inhibit autophagy in BDL- or CCl
- induced liver fibrosis. Quercetin prevented hepatic fibrosis by attenuating hepatic stellate cell activation and reducing autophagy through regulating crosstalk between the TGF-β1/Smads and PI3K/Akt pathways.
Abstract Background Pulmonary hamartomas are benign lung lesions. Histopathologically, pulmonary hamartoma is composed of varying amounts of mesenchymal elements, including chondroid tissue, mature ...adipose tissue, fibrous stroma, smooth muscle, and entrapped respiratory epithelium. Most pulmonary hamartoma cases are asymptomatic and found incidentally during imaging. They usually appear as well-circumscribed lesions with the largest dimension of less than 4 cm. Asymptomatic giant pulmonary hamartomas that more than 8 cm are rare. Case presentation In the current case report, a 12.0 × 9.5 × 7.5 cm lung mass was incidentally noticed in a 59-year-old female during a heart disease workup. Grossly, the lesion was lobulated with pearly white to tan-white solid cut surface and small cystic areas. Microscopically, representative tumor sections demonstrate a chondromyxoid appearance with relatively hypocellular stroma and entrapped respiratory epithelium at the periphery. No significant atypia is noted. No mitosis is noted, and the proliferative index is very low (< 1%) per Ki-67 immunohistochemistry. Mature adipose tissue is easily identifiable in many areas. Histomorphology is consistent with pulmonary hamartoma. A sarcoma-targeted gene fusion panel was further applied to this case. Combined evaluation of microscopic examination and sarcoma-targeted gene fusion panel results excluded malignant sarcomatous transformation in this case. The mediastinal and hilar lymph nodes are histologically benign. After surgery, the patient had an uneventful postoperative period. Conclusions Giant pulmonary hamartoma is rare; our case is an example of a huge hamartoma in an asymptomatic patient. The size of this tumor is concerning. Thus, careful and comprehensive examination of the lesion is required for the correct diagnosis and to rule out co-existent malignancy.
The rapid increase in use of electronic-cigarettes (e-cigarettes), especially among youth, raises the urgency for regulating bodies to make informed decisions, guidance, and policy on these products. ...This study evaluated cardiac function in an experimental model following exposure to e-cigarettes. We subjected C57BL/6 mice to e-cigarette vaping for 2-weeks, and cardiac function was assessed using echocardiography. Cardiac tissues were collected at the end of e-cigarette exposure for pathological analysis. The experimental data showed that e-cigarette vaping (3 h/day for 14 days) had no significant effect on cardiac contractility as measured by ejection fraction. However, it significantly increased angiogenesis in mouse heart tissue. We found that e-cigarette exposure increased the endothelial cell marker CD31 and CD34 to approximately 2 fold (p < 0.05) in heart tissue from female mice and about 150% (p < 0.05) in male mice. E-cigarette vaping also caused slower weight gain compared to mice exposed to room air. In addition, short-term e-cigarette exposure slightly increased collagen content in heart tissue but did not result in significant tissue fibrosis. These results suggest that short-term exposure to e-cigarettes has no acute effect on cardiac contractile function or tissue fibrosis, but it increases cardiac angiogenesis.
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