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Although the association between dietary protein intake and inflammatory bowel disease (IBD) risk has been investigated, the results are inconsistent. Therefore, we conducted a meta-analysis to reassess the relationship between dietary protein intake and IBD risk.The PubMed, Web of Knowledge, and Wanfang databases were searched for pertinent studies through January 31, 2020. Relative risks (RRs) with 95% confidence intervals (CIs) were derived using a random-effect model. Subgroup analyses according to disease type, geographic location, and sex; sensitivity analysis; and publication bias analysis were performed.The current report includes 8 articles consisting of 12 studies with 1069 cases and 330,676 participants. The pooled RR (95% CI) of the highest vs. the lowest categories of dietary protein intake for the IBD risk was 1.561 (0.384-6.347) in cohort studies and 1.060 (0.663-1.694) in case-control studies. Evidence of heterogeneity was found both in cohort studies (I2=86.4%, p=0.007) and in case-control studies (I2=49.0%, p=0.039). However, the association was significant among Asian populations (RR=1.675, 95% CI=1.096-2.559) but not in other populations. We did not find any relationship of dietary protein intake with the risk of either Crohn's disease or ulcerative colitis.Based on limited information, the highest dietary protein intakes among Asians may increase the risk of IBD, undifferentiated for ulcerative colitis or Crohn's disease. This may reflect dietary patterns for which protein is a marker rather than implicate protein itself.

Although previous studies have identified several autonomous pathway components that are required for the promotion of flowering, little is known about how these components cooperate. Here, we identified an autonomous pathway complex (AuPC) containing both known components (FLD, LD and SDG26) and previously unknown components (EFL2, EFL4 and APRF1). Loss-of-function mutations of all of these components result in increased FLC expression and delayed flowering. The delayed-flowering phenotype is independent of photoperiod and can be overcome by vernalization, confirming that the complex specifically functions in the autonomous pathway. Chromatin immunoprecipitation combined with sequencing indicated that, in the AuPC mutants, the histone modifications (H3Ac, H3K4me3 and H3K36me3) associated with transcriptional activation are increased, and the histone modification (H3K27me3) associated with transcriptional repression is reduced, suggesting that the AuPC suppresses FLC expression at least partially by regulating these histone modifications. Moreover, we found that the AuPC component SDG26 associates with FLC chromatin via a previously uncharacterized DNA-binding domain and regulates FLC expression and flowering time independently of its histone methyltransferase activity. Together, these results provide a framework for understanding the molecular mechanism by which the autonomous pathway regulates flowering time.

To explore the water purification efficiency and phytoplankton control efficiency of the water source ecological purification system, and evaluate the effectiveness of the functional group (FG) and morphology-based functional group (MBFG) in response to the internal environment and water quality of the water source ecological purification system, in the summer of 2018, the water quality and phytoplankton functional groups of each unit of the Yanlong Lake ecological purification system were monitored and analyzed. The results showed that the Yanlong Lake water source ecological purification system can effectively purify the water. The average values of total phosphorus, total nitrogen, dissolved oxygen, and turbidity in the influent water were 0.20 mg·L

Although the mechanism of DNA methylation-mediated gene silencing is extensively studied, relatively little is known about how promoter methylated genes are protected from transcriptional silencing. SUVH1, an Arabidopsis Su(var)3-9 homolog, was previously shown to be required for the expression of a few promoter methylated genes. By chromatin immunoprecipitation combined with sequencing, we demonstrate that SUVH1 binds to methylated genomic loci targeted by RNA-directed DNA methylation. SUVH1 and its homolog SUVH3 function partially redundantly and interact with three DNAJ domain-containing homologs, SDJ1, SDJ2, and SDJ3, thus forming a complex which we named SUVH-SDJ. The SUVH-SDJ complex components are co-localized in a large number of methylated promoters and are required for the expression of a subset of promoter methylated genes. We demonstrate that the SUVH-SDJ complex components have transcriptional activation activity. SUVH1 and SUVH3 function synergistically with SDJ1, SDJ2, and SDJ3 and are required for plant viability. This study reveals how the SUVH-SDJ complex protects promoter methylated genes from transcriptional silencing and suggests that the transcriptional activation of promoter methylated genes mediated by the SUVH-SDJ complex may play a critical role in plant growth and development.

To explore the mechanisms of angiogenesis in chronic myeloid leukemia (CML) through detecting the levels of angiogenesis-related factors secreted from K562 cells after overexpression and interference of HIF-1α gene in K562 cells.The K562 cells were transfected by lentiviruses carried and interfered HIF-1α gene, then the transtected K562 cells with carried and interfered with HIF-1α gene were enrolled in overexpression and interference groups respectively, at the same time the K562 cells transfected by the empty virus were enrolled in control group. The cells were harvested after culture for 72 hours under normoxid condition. The transfection efficient in 3 groups was detected by fluorescence microscopy; the mRNA expression of HIF-1α gene and angiogenesis-related factors was detected by RT-PCR; the concentration of angiogenesis-related factors in the caltured supernatant was detected by ELISA.The optimal MOI of K562 cells transfected with lentivirus was 10 and the transfection efficiency was about 50%. The positive rate of transfection after screening by puromycin was more than 90%. The mRNA expression of ANG-I, ANG-II, TGF-α and VEGF in the interference group was lower than that in the over-expression group, and the TGF-β1 mRNA expression in the interference group was higher than in the over-expression group. The mRNA expression of ANG-I and VEGF in the interference group was lower than that in the control group. TGF-αdid not could be detected, and the culture supernatant concentration of ANG-I and TNF-α in the interference group was lower than in the over-expression group, while the VEGF concentration in the interference group was higher than that in the over-expression group. All of the above-mentioned differences were statistically significant (P＜0.05).The positive K562 cells transfected with leutivirus have been harvested by screening with puromycin. The HIF-1α mRNA positively regulates the mRNA expression of ANG-1, ANG-2, TGF-α, VEGF in K562 cells, promotes the antocrine ability of ANG-1 and TNF-α, moreover not stimulates the autocrine of TGF-α, the up-regulation of HIF-1α expression can inhibit the expression TGF-β1 in K562 cells and the autocrine of TGF-β1.HIF-1α对K562细胞血管生成相关因子的影响.通过在K562细胞过表达和干扰HIF-1α后检测K562细胞分泌血管生成相关因子的水平，探讨慢性白血病血管生成的机制.应用携带和干扰HIF-1α基因的慢病毒转染K562细胞，将转染携带和干扰HIF-1α基因的K562细胞分别纳入过表达组、干扰组，同时以空载病毒转染K562细胞纳入对照组。3组细胞在常氧状态下培养72 h后收集细胞，通过荧光显微镜观察3组转染效率，采用RT-PCR法检测HIF-1α和血管相关生成因子mRNA表达水平，ELISA法检测培养上清中血管相关细胞因子的浓度.慢病毒转染K562细胞最佳转染复数（MOI）为10，转染效率为50%左右；经过嘌呤霉筛选后转染阳性细胞达90%以上。干扰组ANG-I、ANG-II、TGF-α和VEGF mRNA表达均低于过表达组，而干扰组TGF-β1 mRNA表达高于过表达组。干扰组ANG-I、VEGF mRNA表达低于对照组；培养上清中未检测到TGF-α，干扰组ANG-I和TNF-α水平低于过表达组，而干扰组VEGF水平高于过表达组；过表达组和干扰组TGF-β1水平均低于对照组，过表达组VEGF水平低于对照组，干扰组VEGF水平高于过表达组和对照组，上述差异具有统计学意义（P＜0.05）.通过嘌呤霉素筛选获得慢病毒转染K562细胞阳性细胞，HIF-1α mRNA正向调控K562细胞ANG-1、ANG-2、TGF-α、VEGF mRNA的表达，促进ANG-I和TNF-α自身分泌的能力，而不刺激TGF-α的自分泌，HIF-1α上调可抑制K562细胞TGF-β1的表达并抑制TGF-β的自分泌.

Although the mechanism of DNA methylation-mediated gene silencing is extensively studied, relatively little is known about how promoter methylated genes are protected from transcriptional silencing. SUVH1, an Arabidopsis Su(var)3-9 homolog, was previously shown to be required for the expression of a few promoter methylated genes. By chromatin immunoprecipitation combined with sequencing, we demonstrate that SUVH1 binds to methylated genomic loci targeted by RNA-directed DNA methylation. SUVH1 and its homolog SUVH3 function partially redundantly and interact with three DNAJ domain-containing homologs, SDJ1, SDJ2, and SDJ3, thus forming a complex which we named SUVH-SDJ. The SUVH-SDJ complex components are co-localized in a large number of methylated promoters and are required for the expression of a subset of promoter methylated genes. We demonstrate that the SUVH-SDJ complex components have transcriptional activation activity. SUVH1 and SUVH3 function synergistically with SDJ1, SDJ2, and SDJ3 and are required for plant viability. This study reveals how the SUVH-SDJ complex protects promoter methylated genes from transcriptional silencing and suggests that the transcriptional activation of promoter methylated genes mediated by the SUVH-SDJ complex may play a critical role in plant growth and development.

The purpose of this work was to produce nanocomposites of polylactic acid with oph-POSS (octaphenyl-Polyhedral Oligomeric Silsesquioxanes)-based biodegradable polyester and study morphology, thermal stability and degradation property. Oph-POSS was synthesized via limited-hydrolytic condensation of phenyl trimethoxysilane catalyzed by tetramethylammonium hydroxide. By adding different mass fractions of oph-POSS into the PLA matrix, oph-POSS/PLA nanocomposites were successfully prepared by the solution casting method using chloroform as solvent. SEM(scanning electron microscopy) observations indicated that oph-POSS were homogeneously dispersed in the PLA matrix. The biodegradation rate of oph-POSS/PLA composites was higher than that of neat PLA, moreover, the degradations of neat PLA and oph-POSS/PLA composites underwent the surface erosion mechanism. It was found that the existence of oph-POSS enhanced thermal stability slightly of nanocomposites relative to neat PLA; however, the thermal degradation mechanism of PLA remained unchanged.

The purpose of this review is to summarize the research progress of PI3K/Akt signaling pathway in erythropoiesis and glycolysis. Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) is activated by numerous genes and leads to protein kinase B (Akt) binding to the cell membrane, with the help of phosphoinositide-dependent kinase, in the PI3K/Akt signal transduction pathway. Threonine and serine phosphorylation contribute to Akt translocation from the cytoplasm to the nucleus and further mediates enzymatic biological effects, including those involved in cell proliferation, apoptosis inhibition, cell migration, vesicle transport and cell cancerous transformation. As a key downstream protein of the PI3K/Akt signaling pathway, hypoxia-inducible factor (HIF)-1 is closely associated with the concentration of oxygen in the environment. Maintaining stable levels of HIF-1 protein is critical under normoxic conditions; however, HIF-1 levels quickly increase under hypoxic conditions. HIF-1α is involved in the acute hypoxic response associated with erythropoietin, whereas HIF-2α is associated with the response to chronic hypoxia. Furthermore, PI3K/Akt can reduce the synthesis of glycogen and increase glycolysis. Inhibition of glycogen synthase kinase 3β activity by phosphorylation of its N-terminal serine increases accumulation of cyclin D1, which promotes the cell cycle and improves cell proliferation through the PI3K/Akt signaling pathway. The PI3K/Akt signaling pathway is closely associated with a variety of enzymatic biological effects and glucose metabolism.

It is a key technology that extract and segment book call number from books’ backbone images for book retrieval and return robot to take an operation of sending and withdrawing books to or from the shelves of library. This paper presents an image extraction and segmentation method using color feature and edge information to segment adjacent book call number with similar background. Take thick, thicker, medium thick, thin, little thin and hybrid books’ backbone images as experiment samples, and the results show that this method effectively extracts and segments adjacent book call number. The segmentation approach provides a technical support for book retrieval and return robot to carry out automatic books’ retrieval and return operation.