COD/TP比及NO_2^--N/TP对短程反硝化聚磷的影响

污水中COD/TP比和NO2--N/TP比对A/A/OSBR反硝化聚磷工艺运行有重要的影响。实验结果表明:随着COD/TP比值的增加,厌氧释磷增加、厌氧释磷速率提高。但当COD/TP比值为28.5时,过剩的碳源进入缺氧段,反硝化菌利用外碳源消耗,抑制了缺氧吸磷过程;当COD/TP比值为21时,合成的PHB不足,缺氧吸磷效率下降,而且长期在较低COD/TP比条件下运行,激发了聚糖菌与聚磷菌的竞争,聚磷菌处于竞争的劣势,反硝化聚磷能力最终消失;当COD/PO43--P为25时,短程反硝化聚磷效果最佳。NO2--N/TP比与COD/TP的比值相关联,在COD/TP=25的条件下,合适的NO2--N/TP比为3。当NO2--N/PO43--P为5时,SBR上一周期剩余的NO2-会影响厌氧释磷过程。当NO2--N/TP为1.8时,NO2-不足,会使反硝化聚磷过程不完全。

NO_2^--N对反硝化除磷系统运行效能的影响

通过改变反硝化聚磷菌(DPAOs)的电子受体类型,考察了不同浓度的NO_2--N作为电子受体时其对反硝化除磷系统运行效能的影响。试验结果表明,在合适的进水NO_2--N浓度范围内,DPAOs经过驯化后能够以NO_2--N为电子受体进行反硝化除磷反应;在短程反硝化除磷系统中,NO_2--N的抑制浓度为30 mg·L-1,当系统进水中的NO_2--N浓度大于30 mg·L-1时,系统的除磷作用及PHA的合成作用均会受到抑制,系统的反硝化效果和COD去除效果亦会出现较为明显的变化,究其原因可能与系统中GAO开始占据优势有关;在短程反硝化除磷系统中,厌氧释磷量与缺氧吸磷量有着良好的线性关系,而对于NO_2--N对DPAOs的抑制机理,笔者将在后续试验中进行深入分析和探究。

CYP24A1 inhibition facilitates the anti-tumor effect of vitamin D3 on colorectal cancer cells

AIM:The effects of vitamin D3 have been investigated on various tumors, including colorectal cancer (CRC). 25-hydroxyvitamin-D3-24-hydroxylase (CYP24A1), the enzyme that inactivates the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 (1,25-D3), is considered to be the main enzyme determining the biological halflife of 1,25-D3. During colorectal carcinogenesis, the expression and concentration of CYP24A1 increases significantly, suggesting that this phenomenon could be responsible for the proposed efficacy of 1,25-D3 in the treatment of CRC. The aim of this study was to investigate the anti-tumor effects of vitamin D3 on the human CRC cell line Caco-2 after inhibition of the cytochrome P450 component of CYP24A1 activity. METHODS:We examined the expression of CYP24A1 mRNA and the effects of 1,25-D3 on the cell line Caco-2 after inhibition of CYP24A1. Cell viability and proliferation were determined by means of sulforhodamine-B staining and bromodeoxyuridine incorporation, respectively, while cytotoxicity was estimated via the lactate dehydrogenase content of the cell culture supernatant. CYP24A1 expression was measured by realtime reverse transcription polymerase chain reaction. A number of tetralone compounds were synthesized to investigate their CP24A1 inhibitory activity. RESULTS:In response to 1,25-D3, CYP24A1 mRNA expression was enhanced significantly, in a time- and dose-dependent manner. Caco-2 cell viability and proliferation were not influenced by the administration of 1,25-D3 alone, but were markedly reduced by coadministration of 1,25-D3 and KD-35, a CYP24A1-inhibiting tetralone. Our data suggest that the mechanism of action of co-administered KD-35 and 1,25-D3 does not involve a direct cytotoxic effect, but rather the inhibition of cell proliferation. CONCLUSION:These findings demonstrate that the selective inhibition of CYP24A1 by compounds such as KD-35 may be a new approach for enhancement of the anti-tumor effect of 1,25-D3 on CRC.

The Inhibition Effect of Tert-Butyl Alcohol on the TiO_2 Nano Assays Photoelectrocatalytic Degradation of Different Organics and Its Mechanism

The inhibition effect of tert-butyl alcohol(TBA), identified as the·OH radical inhibitor, on the TiO_2 nano assays(TNA) photoelectrocatalytic oxidation of different organics such as glucose and phthalate was reported. The adsorption performance of these organics on the TNA photoelectrode was investigated by using the instantaneous photocurrent value, and the degradation property was examined by using the exhausted reaction. The results showed that glucose exhibited the poor adsorption and easy degradation performance, phthalate showed the strong adsorption and harddegradation, but TBA showed the weak adsorption and was the most difficult to be degraded. The degradation of both glucose and phthalate could be inhibited evidently by TBA. But the effect on glucose was more obvious. The different inhibition effects of TBA on different organics could be attributed to the differences in the adsorption and the degradation property. For instance, phthalate of the strong adsorption property could avoid from the capture of·OH radicals by TBA in TNA photoelectrocatalytic process.

3-癸烯-2-酮对马铃薯的抑芽作用机理

为探究3-癸烯-2-酮对马铃薯的抑芽作用,本试验以陇薯7号马铃薯为试验材料,以不做任何抑芽处理为对照,采用0.15 mL·kg^(-1)的3-癸烯-2-酮对萌芽期马铃薯进行熏蒸处理,考察3-癸烯-2-酮处理0~5 d对芽眼部位分生组织和生理指标的影响,并分别对处理后48和72 h的马铃薯样品进行转录组分析。结果表明,3-癸烯-2-酮处理后1~2 d,芽分生组织逐渐坏死,3~4 d完全坏死。与对照相比,3-癸烯-2-酮处理组块茎呼吸速率增加,超氧阴离子(O_(2)^(-)·)、过氧化氢(H_(2)O_(2))含量升高,抗氧化酶活性降低,丙二醛(MDA)和蛋白质羰基含量增加。3-癸烯-2-酮处理使得编码9-LOX基因下调表达,改变了植物激素水平,并使光合作用中叶绿体电子传递系统发生紊乱,从而影响果胶甲酯酶活性,改变细胞壁稳定性,最终引起分生组织细胞在短时间内发生膜质过氧化而抑制马铃薯发芽。在此过程中,谷胱甘肽代谢和苯丙烷生物合成通路对氧化胁迫做出了响应。本研究结果可为进一步探索3-癸烯-2-酮抑制马铃薯发芽的分子机制提供参考。

Synthesis of Fluorinated Heterobicyclic Nitrogen Systems Containing 1,2,4-Triazine Moiety as CDK2 Inhibition Agents

New fluorine substituted heterobicyclic nitrogen system as imidozolopyrimidines (2,3), pyrimido- 1,2,4-triazinones (4-7), 1,2,4-triazinyl-1,2,4-triazine (12-16), 1,2,4-triazinyl-1,2,4-triazinones (14-17) and substituted thiobarbituric acids (19-20), have been synthesized using the reaction of 3- amino-5,6-di (4'-fluorophenyl)-1,2,4-triazine (1) with α,β–bifunctional compounds. Structures of the title compounds were characterized by UV, IR, 1H/13C-NMR and mass spectrometric method. The studied compounds were tested for CDK2 inhibiting activity in DNA damage, as well as in vitro anti-tumor activity.

Inhibition of Coke Formation in Cracking of 2-Methylpentane on USHY by Addition of Steam

在在 673 K 在极端稳定的 HY 上裂开的 2-methylpenatne 的焦炭和次要的产品的形成上的蒸气冲淡的效果被学习了。结果证明那蒸气冲淡压制焦炭和次要的芳香的产品的形成，但是提高 H/C 焦炭和 di 石蜡的生产的原子比率。这和其它证实建议那蒸气冲淡提高焦炭先锋， diolefinic 离子和周期的离子的解吸附作用，由禁止进一步病理学的反应生产 aromatics 和 polyaromatics。进在在稳固的酸催化剂上裂开的烃位于焦炭形成下面的化学的这些卓见能潜在地被用于禁止焦炭形成和控制催化剂释放的添加剂的发展。

H_(2)S/CO_(2)的腐蚀机理及缓蚀体系的研究进展

在油田开采、集输、储运、油气水处理等环节,钢材的腐蚀问题普遍存在。为了将腐蚀风险降至最低,油气田常采用多种方法进行腐蚀防护,其中添加缓蚀剂的方法最为常用。本文综述了近年来在H_(2)S/CO_(2)腐蚀环境下,利用缓蚀剂来抑制金属表面腐蚀的研究进展,论述了CO_(2)、H_(2)S浓度、温度、pH等主控因素对腐蚀程度的影响,对各类主流缓蚀药剂如咪唑啉类缓蚀剂、聚合物类缓蚀剂、曼尼希碱缓蚀剂和有机胺类缓蚀剂的作用效果、原理及优缺点进行了归纳总结,对药剂的研究前景和发展方向进行了展望。

Effects of TSH inhibition after total thyroidectomy on Tg, VEGF, TSGF, CD44V6, sIL-2R and T lymphocyte subsets in patients with differentiated thyroid carcinoma

Objective:To study the effects of TSH inhibition after total thyroidectomy on Tg, VEGF, TSGF, CD44V6, sIL-2R and T lymphocyte subsets in patients with differentiated thyroid carcinoma (DTC).Methods: A total of 100 patients with DTC in our hospital from January 2014 to January 2017 were enrolled in this study. The subjects were divided into the control group (n=50) and the treatment group (n=50) randomly. The control group was treated with thyroid hormone replacement therapy, the treatment group was treated with levothyroxine sodium oral therapy, the two groups were treated for 1 week. The serum Tg, VEGF, TSGF, CD44V6, sIL-2R and peripheral blood CD3+, CD4+, CD8+ of the two groups before and after treatment were compared.Results:There were no significant differences of the serum Tg, VEGF, TSGF, CD44V6, sIL-2R of the two groups before treatment. The serum Tg, VEGF, TSGF, CD44V6, sIL-2R of the two groups after treatment were significantly lower than before treatment, and that of the treatment group after treatment were significantly lower than the control group. There were no significantly differences of the peripheral blood CD3+, CD4+, CD8+ of the two groups before treatment. The peripheral blood CD3+, CD4+ of the two groups after treatment were significantly higher than before treatment, the peripheral blood CD8+ of the two groups after treatment were significantly lower than before treatment, and that of the treatment group after treatment were significantly better than the control group.Conclusion:TSH inhibition after total thyroidectomy for patients with DTC can reduce the serum Tg, VEGF, TSGF, CD44V6, sIL-2R levels, improve the cellular immunity function, and it was worthy clinical application.

Enhanced stability of FA-based perovskite:Rare-earth metal compound EuBr_(2) doping

It is highly desirable to enhance the long-term stability of perovskite solar cells(PSCs)so that this class of photovoltaic cells can be effectively used for the commercialization purposes.In this contribution,attempts have been made to use the two-step sequential method to dope EuBr_(2)into FAMAPbI_(3)perovskite to promote the stability.It is shown that the device durability at 85℃in air with RH of 20%-40%is improved substantially,and simultaneously the champion device efficiency of 23.04%is achieved.The enhancement in stability is attributed to two points:(ⅰ)EuBr_(2)doping effectively inhibits the decomposition andα-δphase transition of perovskite under ambient environment,and(ⅱ)EuBr_(2)aggregates in the oxidized format of Eu(BrO_(3))_(3)at perovskite grain boundaries and surface,hampering humidity erosion and mitigates degradation through coordination with H_(2)O.

2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮诱导Hep3B人肝癌细胞凋亡的机制

近年来,紫草萘醌类衍生物因其临床应用受到副作用的限制。为寻找副作用小疗效高的新型抗肿瘤药物,合成了2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮,并对其化学结构进行了鉴定。同时研究了2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮对人肝癌细胞活力、凋亡的影响及其潜在机制。研究结果表明,通过MTT检测其细胞活力,发现2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮显著降低了人肝癌细胞系的细胞活力。蛋白免疫印迹结果表明,该化合物可通过上调Cle-caspase3、Bad和Bax凋亡相关蛋白表达水平来诱导肝癌细胞Hep3B凋亡。为进一步检测2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮诱导Hep3B细胞发生凋亡的原因,使用荧光探针JC-1检测了2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮处理后Hep3B细胞内线粒体膜电位的变化。结果发现,与对照组相比,药物处理组线粒体膜电位显著下降,绿色荧光增强,红色荧光减弱,说明2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮能通过线粒体损伤来诱导Hep3B细胞凋亡。由于2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮显著诱导Hep3B细胞凋亡。因此,2-(4-甲氧基-苯巯基)-5,8-二甲氧基萘-1,4-二酮具有良好的抗肿瘤活性。

Dual HER2 inhibition strategies in the management of treatment-refractory metastatic colorectal cancer:History and status

Human epidermal growth factor receptor 2(HER2) signaling pathway activation has been identified as a contributor to de novo or acquired resistance to epidermal growth factor receptor(EGFR) inhibitors in a small subset of patients with metastatic colorectal cancer(mCRC). Dual anti-HER2-targeted treatment exhibits strong antitumor activity in preclinical models of HER2-positive mCRC, supporting its testing in clinical trials. The HERACLES trial at four Italian academic cancer centers has confirmed the effectiveness of dual blockage of HER2 with trastuzumab plus lapatinib in patients with heavily pretreated HER2-positive mCRC, refractory to the anti-EGFR antibodies cetuximab or panitumumab. Here, we reviewed the preclinical studies exploring the role of HER2 signaling in the development of anti-EGFR therapy resistance and discussed the status of clinical trials assessing the activity of HER2 inhibitors in this setting.

Antidiabetic effect of Chrysophyllum albidum is mediated by enzyme inhibition and enhancement of glucose uptake via 3T3-L1 adipocytes and C2C12 myotubes

Objective:To investigate the in vivo and in vitro antidiabetic potential of Chrysophyllum albidum.Methods:The effects of oral treatment with hydro-ethanolic extract(125,250 and 500 mg/kg)of the stem bark of Chrysophyllum albidum and glibenclamide for 21 d on glucose level,serum enzyme markers for liver function,lipid profile,total protein,serum urea,serum creatinine,and body weight were evaluated in experimental diabetic rats administered with 45 mg/kg of streptozotocin.In vitro assays including glucose uptake in C2 C12 cells and 3 T3-L1 adipose tissues,α-glucosidase andα-amylase inhibition were employed to evaluate the possible mechanism of hypoglycemic action of the extract.DPPH and nitric oxide radical antioxidant activity of the extract was also measured.Results:The increased levels of blood glucose,triglycerides,lowdensity lipoprotein,total cholesterol,serum aspartate,and alanine transaminases,creatinine,and urea in the diabetic animals were reduced significantly(P<0.01)after treatment with Chrysophyllum albidum extract.The decreased total protein and high-density lipoprotein concentrations were normalized after treatment.In addition,the extract significantly(P<0.01)increased the transport of glucose in 3 T3-L1 cells and C2 C12 myotubes and exhibited considerable potential to inhibitα-amylase andα-glucosidase.It also demonstrated potent antioxidant action by scavenging considerably DPPH and nitric oxide radicals.Conclusions:Chrysophyllum albidum stem bark extract exhibits considerable antidiabetic effect by stimulating glucose uptake and utilization in C2 C12 myotubes and 3 T3-L1 adipocytes as well as inhibiting the activities ofα-amylase andα-glucosidase.

Roles of 5-HT2 receptors in effects of DOM,ketamine and methamphetamine on prepulse inhibition in Sprague Dawley rats

OBJECTIVE Prepulse inhibition(PPI)of the acoustic startle response provides a measure of sensorimotor gating system mecha⁃nisms,which is known to be impaired in schizo⁃phrenia patients.We assessed the effects of the 5-HT2A/2C receptor agonist(±)2,5-dimethoxy-4-methylamphetamine(DOM),the NMDA receptor antagonist ketamine,the dopamine receptor ago⁃nist methamphetamine(Meth)on PPI and the startle magnitude in SD rats.METHODS AND RESULTS Systemic administration of the three compounds all dose-dependently reduced PPI.However,as far as startle magnitude,only DOM at the doses of 3 mg·kg-1 reduced that,while both ketamine and Meth did not change the startle magnitudes.Furthermore,to determine whether 5-HT2A receptor mediate this effect,the non-spe⁃cific 5-HT2 receptor antagonist cyproheptadine,specific 5-HT2A receptor antagonist ketanserin and specific 5-HT2C receptor antagonist SB242084 were tested.Cyproheptadine,ketan⁃serin and SB242084 did not alter startle ampli⁃tude by themselves in SD rats and only ketanserin slightly increased PPI at higher dose(3 mg·kg-1).PPI impairment induced by DOM was restored by pretreatment of cyproheptadine(1 mg·kg-1)and ketanserin(1 mg·kg-1),while not by pretreat⁃ment of SB242084(1 mg·kg-1).Damage of PPI induced by ketamine and Meth was not reversed by cyproheptadine(1 and 5 mg·kg-1).CONCLU⁃SION The receptor mechanisms underlying the disruption of PPI caused by DOM,ketamine and Meth were different from each other,at least 5-HT2A receptor was not the junction receptor for which the three chemicals acted.

S^(2-)/NO_3^--N对硫自养反硝化与厌氧氨氧化耦合脱氮除硫启动的影响

为寻求经济、有效的同步脱氮除硫工艺,采用HABR(复合式厌氧折流板反应器),接种厌氧氨氧化活性污泥,以人工模拟废水为研究对象,在进水p H为8.0、温度为(32±1)℃、HRT为6.5 h的条件下,调整进水S2-/NO3--N〔n(S2-)∶n(NO3--N)〕分别为2.0∶5、3.5∶5、5.0∶5、6.5∶5,研究其对硫自养反硝化和厌氧氨氧化耦合工艺启动的影响,试验连续进行了54 d.结果表明:当S2-/NO3--N<1时,S2-的供应量相对不足,导致硫自养反硝化生成的NO2--N量不足,进而影响后续厌氧氨氧化效果,NH4+-N去除率较低,平均值为53.5%,同时剩余NO3--N继续氧化硫自养反硝化生成的S0,致使出水中ρ(SO42-)增大;当S2-/NO3--N=1时,S2-供应量充足,硫自养反硝化生成NO2--N量最大,厌氧氨氧化效果最好,NH4+-N去除率最高,平均值为65.1%;当S2-/NO3--N>1时,S2-过量,S2-去除率下降.试验通过控制S2-/NO3--N,在HABR内成功实现了硫自养反硝化和厌氧氨氧化耦合工艺启动,NH4+-N、S2-、NO3--N最大去除率分别为74.3%、99.0%、99.5%,S2-/NO3--N=1为最佳比例.

NO_2^-—N对铜绿微囊藻生理特性的影响

采用藻类生物测试标准方法研究了不同NO2--N初始浓度条件下铜绿微囊藻(Microcystis aeruginosa)的生长及生理变化.结果表明,相对BG11(NO2--N初始浓度为0)培养基,低初始NO2--N浓度(1,10mg/L)条件下铜绿微囊藻生长良好;高NO2--N初始浓度(20,30,40mg/L)条件下藻生长缓慢甚至停滞.NO2--N初始浓度由10mg/L到30mg/L,亚硝酸还原酶(NiR)活性和过氧化氢酶(CAT)活性呈增加趋势;在NO2--N初始浓度分别为20～30mg/L和20～40mg/L时,叶绿素a(Chl-a)含量和丙二醛(MDA)含量随NO2--N浓度增大而逐渐升高;在初始NO2--N浓度0,1,10,20,30mg/L条件下硝酸还原酶(NR)没有明显变化.这表明,铜绿微囊藻在NO2--N初始浓度10,20,30mg/L条件下能维持一定的生长,主要由于藻叶绿素含量的增加,NiR活性和防止细胞过氧化的酶CAT活性的提高所致.

MLSS和温度对以NO2--N为电子受体的反硝化除磷的影响研究

对经过长期培养驯化的以NO2^--N为电子受体的反硝化聚磷污泥进行静态烧杯试验，研究了MLSS和温度等因素对反硝化除磷系统处理效果的影响。结果表明，MISS浓度过高或过低都会影响系统对PO4^3--P的去除效果，MLSS为4000mg／L左右时，系统的除磷效果最佳。系统运行的最佳温度为20℃左右，此时系统对PO4^3--P的去除率达到了89．14％。

S^(2-)/NO_3^--N对硫氮同步去除的影响

采用UASB反应器,研究不同S^(2-)/NO_3^--N对硫化物、氨氮和硝态氮同步去除的影响。结果表明,S^(2-)/NO_3^--N在1/1、9/8、5/4、3/2四个阶段反应器稳定运行时,硫化物去除率为80%~100%,氨氮去除率为93%~99%,硝态氮去除率基本稳定在96%左右,脱氮除硫效果良好。在S^(2-)/NO_3^--N为9/8的最佳工艺条件下,硫化物去除率为100%,氨氮去除率达到99%,硝态氮去除率达到96%。同时探讨了S^(2-)/NO_3^--N影响硫氮同步去除的机理。

包膜肥料对水稻土壤渗滤液中NO2^--N、NO3^--N、NH4^＋-N的影响

通过有机玻璃土柱盆栽试验,研究了包膜肥料在水稻不同生育期对不同深度土层的土壤渗滤液中NO2--N、NO3--N、NH4+-N含量的影响。结果表明,土壤渗滤液中NO2--N、NO3--N、NH4+-N质量浓度随着水稻的生长逐渐降低;在水稻分蘖期和拔节期,随着土壤深度的增加NO2--N、NO3--N含量呈现先减小后增大的趋势,NH4+-N含量呈现先增大再减小再增大的趋势;在水稻抽穗期和成熟期,NO2--N、NO3--N含量呈现逐渐减小的趋势,NH4+-N含量呈现增大的趋势。在水稻生育期内与施用普通尿素UR相比,包膜肥料LP40、LPSS、SC60氮素渗滤损失总量分别降低了58.27%,46.38%,33.30%。

一例胭脂鱼亲鱼N0_2^--N急性中毒病例

在2011年胭脂鱼人工繁殖试验中,发现一例亲鱼N02--N急性中毒死亡病例,测定其96hLC50为0.9mg/L,转移至亲鱼塘后得到有效解除,测试安全浓度(SS)为0.005mg/L。胭脂鱼亲鱼N02--N急性中毒病症尚未见报道,该例亲鱼N02--N急性中毒病例的成功抢救,可为胭脂鱼生理生态、人工繁育、鱼病防治、养殖水质管理、资源保护提供参考。