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Hypoxia inducible factor 1α (HIF1α) is abnormally overexpressed in t(8;21) acute myeloid leukemia (AML) and functions as an oncogene through transactivating DNA methyltransferase 3 alpha leading to DNA hypermethylation. However, it remains unclear whether HIF1α influences RNA N6-methyladenosine (m6A) methyltransferases. Here, we show that HIF1α promotes the expression of Wilms tumor 1-associated protein (WTAP), a main component of the m6A methyltransferase complex, markedly alters the transcriptome-wide m6A distribution and enhances cell proliferation in t(8;21) AML. In agreement with this, WTAP is overexpressed and predicts poor prognosis in t(8;21) AML patients. Moreover, WTAP knockdown inhibits growth, and induces apoptosis and differentiation of leukemia cells. Mechanistically, HIF1α transactivates WTAP gene expression by directly binding to the hypoxia-response element of its promoter region. Pharmacological or genetic intervention in the HIF1α-WTAP axis results in the reduction of m6A level on lysine demethylase 4B (KDM4B) transcripts and increased its degradation, correlated with lower expression of KDM4B and higher trimethylation levels of histone H3 on lysine 9. KDM4B knockdown inhibits leukemia cell growth in vitro and in mice. Thus, HIF1α-mediated WTAP high expression enhances the malignant behavior of leukemia cells and drives a crosstalk between m6A RNA methylation and histone methylation through monitoring m6A-dependant KDM4B translation.

The t(8;21) fusion product, AML1/ETO, and hypoxia-inducible factor 1α (HIF1α) form a feed-forward transcription loop that cooperatively transactivates the DNA methyltransferase 3agene promoter that leads to DNA hypermethylation and drives leukemia cell growth. Suppression of the RNA N6-methyladenosine (m6A)-reader enzyme YTH N6-methyladenosine RNA binding protein 2 (YTHDF2) specifically compromises cancer stem cells in acute myeloid leukemia (AML) but promotes hematopoietic stem cell expansion without derailing normal hematopoiesis. However, the relevance of expression between AML1/ETO-HIF1αloop and YTHDF2, and its functional relationship with t(8;21) AML have not been documented. Here, we show that YTHDF2is highly expressed in t(8;21) AML patients and associated with a higher risk of relapse and inferior relapse-free survival. Knockdown of YTHDF2 in leukemia cells causes an impaired cell proliferation rate in vitro and in mice. Mechanistically, HIF1α is able to bind to the hypoxia-response elements of the 5′-untranslated region of the YTHDF2gene and promotes the transactivity of the YTHDF2promoter. Knockdown and overexpression of either AML1/ETOor HIF1αresulted in decreased and increased YTHDF2 protein and mRNA expression in t(8;21) AML cells. In particular, knockdown of YTHDF2 resulted in increased global mRNA m6A levels in t(8;21) AML cells, accompanied by increased TNF receptor superfamily member 1b(TNFRSF1b) mRNA and protein expression levels. Last, we demonstrated that the m6A methylation and expression levels of the TNFRSF1bgene were both negatively correlated with HIF1αexpression levels. In conclusion, YTHDF2 is a downstream target of the AML1/ETO-HIF1α loop and promotes cell proliferation probably by modulating the global m6A methylation in t(8;21) AML.

In this paper, ammonium polyphosphate (APP) was modified by methyl hydrogen silicone oil and gas hydrophobic silica, hydrophobic ammonium polyphosphate (HAPP) was prepared. Then, HAPP was separately mixed with starch and melamine were introduced into polypropylene as flame retardants to prepare polypropylene (PP) retardant materials. The hydrophobic retention was of HAPP above 90%. According to the results from testing its wettability, its contact angle was 140.69°, which was increased by about 120°compared with APP, and this indicated the HAPP had better hydrophobic properties than that of the unmodified. And a comprehensive analysis is conducted on the scanning electron microscope (SEM) and infrared spectroscopy (FTIR).The results showed that the surface of APP is coated with methyl hydrogen silicone fluid and gas hydrophobic silica. The limited oxygen index (LOI) of the flame retardant PP material is measured by the oxygen index tester, and at a total flame retardant loading of 33wt%, the LOI value of PP retardant materials can achieve 29%, indicating that this flame retardant can better make the PP into the stable charred layer, and improve the performance of the flame retardant PP material greatly.

Stable and uniformly dispersive silver nanoparticles were prepared though reducing silver nitrate with polyvinylpyrrolidone. The effects of preparing conditions on the stability of silver nanoparticles were investigated. The results showed that the surface plasmon resonance (SPR) band of the silver nanoparticles was about 403nm. The silver nanoparticles remained stable for more than one month. Water, alkali solution and glucose could accelerate the reaction. The stability of the silver nanoparticles was increased by adding glucose.

In order to reduce the emission of CO2 and control the global greenhouse effect, the paper introduces and compares two new technologies named chemical-looping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU) that are both high-efficient and clean. Through comparative analysis, CLC has been widely studied because of its direct separation of CO2, reduction loss of the heat, improvement of energy efficiency and avoiding of the generation of fuel type NOx in the combustion process. Besides the current research for metal oxygen carrier, there are some scholars find various non-metal oxygen carriers that have the better performance in CLC. But the study on reactors of CLC is still not mature, especially the solid fuel reactor, which is different from CLOU. In a certain sense, CLOU is an improved technology based CLC, besides the bove advantages, it also can react with coal directly. Many scholars use coal as fuel in the fluidized bed by the technology of CLOU, and the results of them are feasible. So from this perspective, CLOU technology has more broad prospects than CLC in the China.

Abstract: Objective: To determine the potential effectiveness and toxicity of this therapy in children with advanced neuroblastoma or malignant lymphoma. Methods: Carboplatin (425 mg/m2�d) and etoposide (338 mg/m2�d) were given as a 24 h continuous IV infusion on days -7, -6, -5 and -4, and melphalam (70 mg/m2�d) by bolus IV infusion at hour 0 of days -7, -6, and-5(CEM). Or busulphan was given as 1 mg/kg�6 h orally on days -6, -5, -4, and melphalam (140 mg/m2) by IV bolus infusion on day — 3(BM). Treatment regimens followed by autologous PBSC infusion were performed in 19 children with neuroblastoma (n=12) or malignant lymphoma (n=7) for consolidation treatment. There were thirteen males and six females, with a median age of 6.4 years (raging 3.5∼13 years). Results: The median period of achieving ANC >0.5�109/L, WBC>1.0�109/L, and platelet >20�109/L after infusion of PBSCs were 21 d, 17 d, and 33 d respectively. Stomatitis occurred in 16 children (86%), and twelve had gastrointestinal toxicity (64%). Complete remission (CR) was achieved in 14 (74%) children. Fifteen patients (79%) survived. Ten patients (53%) are alive in CR. These patients are alive for a median of 639 days and disease-free for 909 d after transplantation. Four cases (21%) relapsed, and four cases (21%) died. Conclusion: CEM or BM regimen followed by autologous PBSCT infusion is safe and feasible, and has significant effects in children with advanced neuroblastoma or malignant lymphoma.