Diagnostic value of methylated branched chain amino acid transaminase 1/IKAROS family zinc finger 1 for colorectal cancer

BACKGROUND The diagnostic value of combined methylated branched chain amino acid transaminase 1(BCAT1)/IKAROS family zinc finger 1(IKZF1)in plasma for colorectal cancer(CRC)has been explored since 2015.Recently,several related studies have published their results and showed its diagnostic efficacy.AIM To analyze the diagnostic value of methylated BCAT1/IKZF1 in plasma for screening and postoperative follow-up of CRC.METHODS The candidate studies were identified by searching the PubMed,Embase,Cochrane Library,CNKI,and Wanfang databases from May 31,2003 to June 1,2023.Sensitivity,specificity,and diagnostic accuracy were calculated by merging ratios or means.RESULTS Twelve eligible studies were included in the analysis,involving 6561 participants.The sensitivity of methylated BCAT1/IKZF1 in plasma for CRC diagnosis was 60%[95%confidence interval(CI)53-67]and specificity was 92%(95%CI:90-94).The positive and negative likelihood ratios were 8.0(95%CI:5.8-11.0)and 0.43(95%CI:0.36-0.52),respectively.Diagnostic odds ratio was 19(95%CI:11-30)and area under the curve was 0.88(95%CI:0.85-0.91).The sensitivity and specificity for CRC screening were 64%(95%CI:59-69)and 92%(95%CI:91-93),respectively.The sensitivity and specificity for recurrence detection during follow-up were 54%CONCLUSION The detection of methylated BCAT1/IKZF1 in plasma,as a non-invasive detection method of circulating tumor DNA,has potential CRC diagnosis,but the clinical application prospect needs to be further explored.

支链氨基酸转氨酶1在食管鳞癌中的表达及其临床意义

目的探讨食管鳞癌(ESCC)患者癌组织中支链氨基酸转氨酶1(BCAT1)的表达及临床意义。方法采用qRT-PCR和Western blot技术检测食管鳞癌细胞系中BCAT1基因的表达水平,筛选出合适的食管癌细胞,作为后续研究。敲低和过表达BCAT1,采用Western blot检测ESCC细胞中BCAT1的蛋白表达水平。CCK-8活力测定、克隆形成实验、划痕实验、Transwell检测ESCC细胞增殖、迁移和侵袭等细胞表型的变化。结果qRT-PCR和Western blot结果显示,与正常细胞相比,BCAT1在ESCC中的相对表达量降低,尤其是KYSE150和Eca109细胞更为明显,因此选择这两株细胞进行研究。CCK-8细胞增殖实验结果显示,细胞在转染BCAT1 siRNA 48 h后,其增殖率明显高于对照组;而过表达BCAT1之后,效果则相反。克隆形成实验结果表明,BCAT1的敲低显著促进ESCC细胞的克隆形成,而BCAT1的过表达显著抑制ESCC细胞的克隆形成。细胞划痕实验和Transwell实验结果表明,与Control siRNA组相比,BCAT1 siRNA组ESCC细胞的迁移和侵袭明显升高;而过表达组中ESCC细胞的迁移和侵袭明显受到抑制。结论BCAT1在ESCC中低表达,BCAT1低表达显著促进ESCC细胞增殖、迁移和侵袭。

猴痘病毒B.1谱系遗传分支、毒力基因及蛋白功能

2022年以来,猴痘疫情在全球暴发和流行。相较以往的猴痘病毒,2022年流行的猴痘毒株传播能力和宿主适应性等明显增强,猴痘B.1谱系毒株已成为全球猴痘疫情流行的主要毒株。为此,本文对猴痘病毒B.1谱系遗传分支、毒力基因及蛋白功能进行综述,并就部分基因产物的蛋白功能进行了注释,以期为猴痘疫情的科学防控提供参考。

BCAT1作为胰腺导管腺癌潜在诊断标志物的临床应用价值研究

目的 本研究拟验证前期研究发现的bcat1基因表达产物支链氨基酸转氨酶1(BCAT1)作为胰腺导管腺癌潜在血清学诊断标志物的临床应用价值。方法 收集临床PDAC患者血清样本作为实验组,收集胃癌、肝癌、结直肠癌、慢性胰腺炎患者及健康人群血清样本作为对照,采用酶联免疫吸附实验(ELISA)检测血清样本BCAT1浓度,验证其作为标志物的临床诊断价值。结果 ELISA结果显示PDAC组患者血清BCAT1浓度显著高于健康对照组,差异有统计学意义(P<0.05,U=1 206)。PDAC组患者血清BCAT1浓度高于慢性胰腺炎组,差异有统计学意义(P<0.05,H=33.80);与其他消化道肿瘤相比,高于肝癌组和结直肠癌组,差异有统计学意义(P<0.05,H=33.80),与胃癌组差异无统计学意义(P>0.05,H=33.80)。BCAT1与CA19-9的相关性较好,且差异有统计学意义(P<0.05,R^(2)=0.080 52),与CEA(R^(2)=2.265e-005)、CA125(R^(2)=0.025 88)和CA72-4(R^(2)=0.007 7)相关性较低,差异无统计学意义(P>0.05);BCAT1诊断PDAC的AUC优于CA72-4,与CA125和CEA相当,劣于CA19-9;BCAT1 cut off值为1.556ng/mL,敏感度为64.1%,特异度为80%。BCAT1在PDAC早中期患者血清浓度中位数为0.283 ng/mL,晚期患者升高为0.482 ng/mL,差异有统计学意义(P<0.05,U=1029);在肿瘤≥40 mm(U=641)、中低分化(U=435)、胰头部位(H=2.767)均表现为表达水平升高,差异无统计学意义(P均>0.05)。动态观测的BCAT1浓度在第0天和1~30天(U=44)、31~60天和61~90天(U=36)浓度差异有统计学意义(P均<0.05)。结论 BCAT1作为潜在的血清学标志物,对于PDAC的鉴别诊断、肿瘤分期、疾病进展判断具有参考价值,是目前现有的PDAC血清标志物的有益补充。

BCAT1抑制剂BAY-069的合成工艺优化

BAY-069是目前体外活性最强的支链氨基酸转氨酶1(BCAT1)抑制剂,但其报道的合成路线存在原料成本较高、总收率极低和中间体结构表征不充分等缺点。本研究基于已有合成路线,重点对其合成工艺中的Ullmann偶联反应进行了系统优化。以1-硝基萘(1)为起始原料,经过7步反应和手性色谱柱手性拆分合成目标化合物BAY-069。所有中间体和目标化合物均经1 H NMR,13 C NMR和HR-MS表征。以Ullmann偶联反应为主要优化步骤的路线,其优化后的总收率为11.0%(3b→(±)-BAY-069),是原总收率1.6%(3a→(±)-BAY-069)的6.9倍。

Isolation and Functional Analysis of the Regulation of Branching by Isopentenyl Transferase Gene CmIPT1 in <i>Chrysanthemum morifolium </i>cv. ‘Jinba’

Today’s chrysanthemums are highly evolved flowering plants and they are considered as one of the most important ornamental cut flowers. In this research an isopentenyl transferase gene named CmIPT1 was isolated from Chrysanthemum morifolium cv. ‘Jinba’ using RACE and RT-PCR methods. The full cDNA sequence of CmIPT1 was 873 bp which encoded a deduced protein of 290 amino acids. It contained GxxGxGKS which is a conserved sequence of the typical domain of IPT family. The phylogenetic tree analysis of CmIPT1 in Chrysanthemum morifolium cv. ‘Jinba’ shows that it has the closest relationship with CcIPT1 in Cynara cardunculus var. scolymus. Expression of CmIPT1 was higher in stems and apex, whereas it was lower in leaves and roots. And the overexpression of CmIPT1 obviously increased the number of rosette branches in Arabidopsis. Here, in our study, we showed that CmIPT1 is a positive regulator of branch development in Chrysanthemum and may play a key role in regulating lateral branch formation of Chrysanthemum plants.

Branching ratio and angular distribution of ejected electrons from Eu 4f^76p_(1/2)nd auto-ionizing states

The branching ratios of ions and the angular distributions of electrons ejected from the Eu 4f^76p_（1/2）nd auto-ionizing states are investigated with the velocity-map-imaging technique.To populate the above auto-ionizing states,the relevant bound Rydberg states have to be detected first.Two new bound Rydberg states are identified in the region between41150 cm^（-1）and 44580 cm^（-1）,from which auto-ionization spectra of the Eu 4f^76p_（1/2）nd states are observed with isolated core excitation method.With all preparations above,the branching ratios from the above auto-ionizing states to different final ionic states and the angular distributions of electrons ejected from these processes are measured systematically.Energy dependence of branching ratios and anisotropy parameters within the auto-ionization spectra are carefully analyzed,followed by a qualitative interpretation.

A branch-and-bound algorithm for multi-dimensional quadratic 0-1 knapsack problems

In this paper, a branch-and-bound method for solving multi-dimensional quadratic 0-1 knapsack problems was studied. The method was based on the Lagrangian relaxation and the surrogate constraint technique for finding feasible solutions. The Lagrangian relaxations were solved with the maximum-flow algorithm and the Lagrangian bounds was determined with the outer approximation method. Computational results show the efficiency of the proposed method for multi-dimensional quadratic 0-1 knapsack problems.

Cotton GhBRC1 regulates branching,flowering,and growth by integrating multiple hormone pathways

Cotton architecture is partly determined by shoot branching and flowering patterns.Gh BRC1 was previously identified by RNA-seq analysis of nulliplex-branching and normal-branching cotton.However,the roles of Gh BRC1 in cotton remain unclear.In the present study,investigations of nuclear localization and transcriptional activity indicated that Gh BRC1 has characteristics typical of transcription factors.Gene expression analysis showed that Gh BRC1 was highly expressed in axillary buds but displayed different expression patterns between the two branching types.Overexpression of Gh BRC1 in Arabidopsis significantly inhibited the number of branches and promoted flowering.In contrast,silencing Gh BRC1 in cotton significantly promoted seedling growth.Gh BRC1 was induced by multiple hormones,including strigolactones,which promoted seedling growth and seed germination of Arabidopsis plants overexpressing Gh BRC1.Consistent with these findings,RNA-seq analysis of virus-induced gene silencing treated cotton revealed that a large number of genes were differentially expressed between Gh BRC1-silenced and control plants,and these genes were significantly enriched in plant hormone signalling pathways.Together,our data indicates that Gh BRC1 regulates plant branching and flowering through multiple regulatory pathways,especially those regulating plant hormones,with functions partly differing from those of Arabidopsis BRC1.These results provide insights into the molecular mechanisms controlling plant architecture,which is important for breeding cotton with ideal plant architecture and high yield.

梨矮化砧木中矮1号绿枝扦插繁殖研究

探索梨矮化砧木中矮1号扦插繁殖难以生根的技术问题,为其在生产中作为自根砧推广应用提供理论和技术支持。以中矮1号当年生绿枝为插穗材料,研究不同基质、不同药剂配比及浓度对其扦插的影响,通过正交设计试验分析影响中矮1号绿枝扦插生根的主要因素。结果表明:5种基质中,蛭石的扦插效果最好;经过药剂处理后的插穗,扦插效果显著优于对照,相比于较高质量浓度(3000~4000 mg/L)的药剂处理,较低质量浓度(2000~2500 mg/L)的药剂更有利于插穗的生长;正交设计试验结果表明,枝条部位是影响插穗存活率、愈伤组织诱导率的主要因素,而IBA则是影响插穗生根率的主要植物生长调节剂。中矮1号新梢中下部绿枝经过2500 mg/L IBA+NAA(3∶1)速蘸1 s处理后扦插于蛭石基质中,最高获得了10.0%的插穗生根率。

Exploration and Validation of the Potential Downstream Genes Underlying ipa1-2D Locus for Rice Panicle Branching

In recent years,some super hybrid rice varieties were bred with strong culms and large panicles,which are mainly contributed by the ipa1-2D locus.A gain-of-function allele of OsSPL14 is the ipa1-2D and it can greatly increase the panicle primary branch number.However,the key downstream genes mediating this trait variation are not fully explored.In this study,we developed high-quality near-isogenic lines(NILs)with a difference of only 30 kb chromosomal segment covering the ipa1-2D locus.Using the NILs,we explored the impact of ipa1-2D on five sequential stages of early inflorescence development,and found that the locus can greatly enhance the initiation of primary branch meristems.A transcriptomic analysis was performed to unveil the downstream molecular network of ipa1-2D,and 87 genes were found differentially expressed,many of which are involved in metabolism and catalysis processes.In addition,transgenic lines of overexpression and RNA interference were generated to shape different levels of OsSPL14.They were also used to validate the expression variation explored by transcriptome.Based on the gene annotation,twelve potential downstream targets of ipa1-2D were selected,and their expression variation was confirmed by qRT-PCR analysis both in NILs and transgenic lines.This research expands the molecular network underlying ipa1-2D and provides novel gene information which might be involved in the control of panicle branching.We discussed the potential function of identified genes and highlighted their values for future function exploration and breeding application.

等规聚丁烯-1扩链改性及其超临界CO_(2)发泡行为研究

以过氧化二异丙苯(DCP)为引发剂、二甲基二硫代氨基甲酸锌(ZDMC)和季戊四醇三丙烯酸酯(PETA)为双单体,制备出具有长链支化结构和交联结构等规聚丁烯-1(iPB-1),并采用超临界CO_(2)发泡制备iPB-1发泡材料。研究扩链改性对iPB-1的熔融结晶、流变行为和发泡行为的影响。结果表明,长链支化结构提高了iPB-1的结晶温度并降低了iPB-1结晶度;改性iPB-1的熔体黏弹性提高、松弛时间增加、剪切稀化现象更为明显,同时表现出显著的应变硬化现象;长链支化改性iPB-1具有更宽的发泡温度区间和更均匀的泡孔结构。

支链氨基酸转移酶1在肿瘤发生与进展中的作用机制

支链氨基酸转移酶1(branched-chain amino acid transaminase 1,BCAT1)催化支链氨基酸(branched-chain amino acids,BCAA)和支链酮酸(branched-chain keto acids,BCKA)之间的转换反应,在维持二者稳态中发挥重要作用。近年来人们发现,BCAT1在多种恶性肿瘤中高表达,且与癌症的分期和预后关系密切,进一步研究证实,BCAT1能促进癌细胞的增殖、侵袭和转移,并揭示BCAT1在癌症发生发展中的部分作用机制:(1)不同肿瘤中BCAT1催化转氨基反应的方向不同,BCAT1既可催化BCAA分解为BCKA,也可催化BCKA合成BCAA,这两个方向都可能促进癌症的发生和发展;(2)BCAT1既能直接影响肿瘤细胞代谢来发挥相关作用,也能通过影响肿瘤微环境而产生促癌效应。总体而言,BCAT1通过催化BCAA的分解与合成反应,影响物质代谢、能量合成、信号通路、肿瘤免疫、表观遗传学和细胞周期等方面,进而促进癌症的发生与进展。本文就国内外BCAT1和BCAA的研究进展,聚焦BCAT1在肿瘤发生发展中的作用机制做一综述,为进一步探讨BCAT1在恶性肿瘤研究中的应用前景提供理论依据。

“2+1”高职生定向培养中临时党支部建设的意义、困难与对策——以铁路企业为例

随着铁路企业高职生“2+1”定向培养走向常态化、纵深化,学员中流动党员的教育、管理和监督成为铁路企业和高职院校学生党建工作所面临的重要问题。“2+1”高职生定向培养阶段临时党支部建设对保障育人方向、加强党员教育、加深产教融合等具有重要意义,但存在意识不强、职责不明、制度不全、党性不足等问题,具体的解决对策有以解决问题为导向提高思想站位、以校企合作为载体明确责任主体、以配套制度为切入确立管理机制、以加强教育为抓手提高党性修养。

求解0-1背包问题的多种算法策略的分析

0-1背包问题是一个经典的组合优化问题,常常被应用于资源分配、物流管理等领域,并且在计算机科学和数学中具有重要的理论价值。解决0-1背包问题有多种策略,常见的策略为动态规划法、回溯法和分支限界法,为了确定对该问题求解的最有效方法,研究三种算法求解的性能表现是十分必要的。通过探讨求解0-1背包问题的三种不同算法,并给出该问题的动态规划法、回溯法和分支限界法的求解思路和算法设计,然后通过实验对比和分析三者的运行时间效率。实验表明,三种算法各具优缺点,要根据问题特点和需求来灵活选择算法。

密度和施肥水平对双低油菜苏油1号产量及分枝习性的影响

密度和施肥水平两因子对苏油 1号产量及分枝习性影响的研究结果表明 :( 1)移栽 11.2 5万株 /hm2 、施纯氮 2 70kg/hm2 是适宜苏油 1号的种植密度和施肥处理 ,产量达到 34 5 2 .0kg/hm2 。 ( 2 )产量结构因子以单位面积有效角果数对产量的影响较大 ,其次为千粒重和每角粒数。 ( 3)随密度和施氮量增加 ,单位面积有效角果数呈先增后减的趋势。千粒重与施氮量关系密切 ,但过量施氮则降低千粒重。 ( 4)单位面积分枝数多、分枝角果数多和分枝籽粒多是苏油

几种食用菌对桑枝屑基料中1-脱氧野尻霉素的富集能力

用含有生物活性物质1-脱氧野尻霉素(DNJ)的桑枝碎屑作为培养基料培养普通食用菌,通过高效液相色谱法检测分析不同食用菌对桑枝屑基料中DNJ的富集能力。结果表明:黑木耳、灵芝均能够富集桑枝屑基料中的DNJ,其中灵芝的富集能力最强,干物中DNJ的质量分数达0.645 9%,黑木耳干物中DNJ的质量分数为0.385 4%;香菇对桑枝DNJ基本没有富集能力。所用夏伐桑枝条干物中DNJ的质量分数为0.889 3%,灵芝和黑木耳对桑枝屑基料中DNJ的吸收效率分别达到72.63%、43.34%。今后可利用桑枝条碎屑作培养基料培养对DNJ有较强富集能力的食用菌,提高桑枝食用菌的药用保健功效。

基于拟合方法的N-1静态电压稳定裕度计算

提出一种兼顾精度与速度的计算线路N-1故障下静态电压稳定临界点的拟合方法。该方法用左特征向量排队找出较严重故障,再利用泰勒级数求得电压崩溃点处状态变量和负荷裕度对严重故障支路连接参数的1～3阶灵敏度,在此基础上用四参数拟合方法进行逼近,从而快速精确地求解出关键线路故障情况下电压稳定临界点。该方法能快速地对线路故障按严重程度进行排序,并精确得出故障后电压稳定裕度,可用于调度中心作监控估算工具。IEEE30及IEEE57母线系统上的算例验证了该方法。

河3-支平1井TAML5级分支井钻完井技术

为满足分支井眼可以合采也可以分采的要求,验证TAML5级完井分支井技术对胜利油田复杂地质环境的适应性,胜利油田在河3区块部署了1口TAML5级完井分支水平井———河3-支平1井。该井施工工艺复杂,操作难度大,对井径扩大率要求高,对井眼轨迹要求严格,复杂尾管串下入难度大,对井眼连接器总成和上分支井眼回接的密封性能要求高。该井在钻完井过程中综合应用了地质导向钻井、井眼轨道优选、套管开窗侧钻、陀螺定向、防碰绕障、井径扩大率控制与井壁稳定技术,确保了该井的顺利完成,为TAML 5级完井分支井技术的推广应用积累了经验。分析了该井钻完井的主要技术难点,介绍了该井的工程设计、钻完井技术措施,重点介绍了该井的完井过程。