高效液相色谱法测定接骨片中阿魏酸和芍药苷

目的 分析四倍体菘蓝Isatis indigotica基因组DNA甲基化水平和模式。方法 采用甲基化敏感扩增多态性（methylation sensitive amplification polymorphism,MSAP）方法,对四倍体菘蓝基因组DNA的甲基化水平和模式进行分析。结果 筛选36对MSAP选择性引物进行扩增,共得到1 733条清晰的条带。二倍体菘蓝基因组胞嘧啶甲基化水平为24.05%,四倍体菘蓝基因组胞嘧啶甲基化水平为23.70%。检测到83个（4.86%）CCGG位点在四倍体菘蓝基因组中发生了DNA甲基化模式的改变,其中37个（2.13%）位点发生了超甲基化,36个（2.08%）位点发生了去甲基化。结论 二倍体和四倍体菘蓝在CCGG位点上存在胞嘧啶甲基化状态的改变。     

Mismatch repair system decreases cell survival by stabilizing the tetraploid G1 arrest in response to SN‐38

The role of the mismatch repair (MMR) system in correcting base–base mismatches is well established; its involvement in the response to DNA double strand breaks, however, is less clear. We investigated the influence of the essential component of MMR, the hMLH1 protein, on the cellular response to DNA‐double strand breaks induced by treatment with SN‐38, the active metabolite of topoisomerase I inhibitor irinotecan, in a strictly isogenic cell system (p53^wt, hMLH1⁺/p53^wt, hMLH1^?). By using hMLH1 expressing clones or cells transduced with the hMLH1‐expressing adenovirus as well as siRNA technology, we show that in response to SN‐38‐induced DNA damage the MMR proficient (MMR⁺) cells make: (i) a stronger G2/M arrest, (ii) a subsequent longer tetraploid G1 arrest, (iii) a stronger activation of Chk1 and Chk2 kinases than the MMR deficient (MMR^?) counterparts. Both Cdk2 and Cdk4 kinases contribute to the basal tetraploid G1 arrest in MMR⁺ and MMR^? cells. Although the Chk1 kinase is involved in the G2/M arrest, neither Chk1 nor Chk2 are involved in the enhancement of the tetraploid G1 arrest. The long‐lasting tetraploid G1 arrest of MMR⁺ cells is associated with their lower clonogenic survival after SN‐38 treatment, the abrogation of the tetraploid G1 arrest resulted in their better clonogenic survival. These data show that the stabilization of the tetraploid G1 arrest in response to double strand breaks is a novel function of the MMR system that contributes to the lesser survival of MMR⁺ cells.     

用导数光谱考查两种倍性水平北板蓝根及鉴别南北板蓝根

用导数光谱考查两种倍性水平北板蓝根及鉴别北板蓝根和南板蓝根。实验结果表明，两种倍性水平北板蓝根导数光谱特征一致，并与南板蓝根有显著差异。     

高山红景天同源四倍体诱导与鉴定研究

目的 获得高山红景天同源四倍体无性体系。方法 秋水仙素诱导种子加倍,通过多次组培再生进行嵌合体分离,采用气孔大小与密度测量、染色体计数和流式细胞学分析进行倍性鉴定。结果 秋水仙素质量分数与处理时间对种子萌发率、幼苗死亡率及诱变率均有十分明显的影响,0.2%秋水仙素处理露白种子72 h的萌发率、幼苗死亡率及诱变率分别为18.2%、73.6%、68.7%;倍性变异植株气孔明显增大,气孔密度变小;正常二倍体染色体数目为2n＝2x＝26,四倍体染色体数为 2n＝4x＝52,发现非整倍体的存在;倍性变异植株经3次再生纯化后获得纯合四倍体无性系,流式细胞学检测无嵌合体存在。结论 秋水仙素处理高山红景天种子获得同源四倍体具有可行性。     

四倍体菘蓝基因组DNA甲基化的甲基化敏感扩增多态性分析

目的 分析四倍体菘蓝Isatis indigotica基因组DNA甲基化水平和模式.方法 采用甲基化敏感扩增多态性(methylation sensitive amplification polymorphism,MSAP)方法,对四倍体菘蓝基因组DNA的甲基化水平和模式进行分析.结果 筛选36对MSAP选择性引物进行扩增,共得到1733条清晰的条带.二倍体菘蓝基因组胞嘧啶甲基化水平为24.05％,四倍体菘蓝基因组胞嘧啶甲基化水平为23.70％.检测到83个(4.86％) CCGG位点在四倍体菘蓝基因组中发生了DNA甲基化模式的改变,其中37个(2.13％)位点发生了超甲基化,36个(2.08％)位点发生了去甲基化.结论 二倍体和四倍体菘蓝在CCGG位点上存在胞嘧啶甲基化状态的改变.     

Transient window of resilience during early development minimizes teratogenic effects of heat in zebrafish embryos

Background: Transient heat shock during early development is an established experimental paradigm for doubling the genome of the zebrafish zygote, which has practical applications in expedited identification of recessive mutations in genetic screens. Despite the simplicity of the strategy and the genetic tractability of zebrafish, heat shock has not been used for genome doubling since the proof‐of‐principle experiments done in the 1980s. This is because of poor survival of embryos that ensue from transient heat shocks and gross developmental abnormalities in the few survivors, which is incompatible with phenotype driven screens. Results: We show that heat shocks during early zebrafish development uncouple the second cycle of DNA and centrosome duplication. Interestingly, the developmental time of the heat shock that triggers the dissociation between DNA and centrosome duplication cycles significantly affect the potential of embryos to survive and attain normal morphology. The potential to develop normally after a heat shock alters in a developmental time span of 2 min in zebrafish embryos, a phenomenon that has not been reported in any species. Conclusions: The existence of heat resilient developmental windows and reduced heat teratogenicity during these windows could be an effective step forward in practical application of transient heat for experimental manipulation of ploidy in zebrafish. More broadly, heat resilience before zygotic genome activation suggests that metazoan embryos may possess innate protective features against heat beyond the canonical heat shock response. Developmental Dynamics 247:992–1004, 2018. © 2018 Wiley Periodicals, Inc.     

四倍体金银花水提物抗炎作用和急性毒性实验研究

目的对四倍体金银花水提物的抗炎作用以及急性毒性进行评价。方法以二倍体金银花为对照,分别采用角叉菜胶诱导大鼠足肿胀实验、大鼠棉球肉芽肿实验对四倍体金银花水提物进行抗炎活性评价;采用Bliss法测定小鼠的半数致死量(LD50)对其进行急性毒性评价。结果四倍体金银花水提物具有明显的抗急性炎症作用,与亲本二倍体金银花之间抗炎作用差异不具有统计学意义,2个种质均不具有明显的抗亚急性炎症作用。四倍体和二倍体金银花水提物ig给药对小鼠的LD50值分别为72.12、69.92 g/kg,急性毒性差异不明显,分别相当于人体(体质量60 kg)安全用量的412和400倍。结论四倍体金银花水提物具有明显的抗急性炎症作用,在一定剂量范围内使用较为安全。     

15q11.2-13.2微重复四倍体综合征1例并文献复习

目的 采用分子遗传学技术分析1例常规染色体核型拟诊为21/22三体的发育迟缓伴孤独症患儿,明确遗传学诊断。方法 收集患儿及其父母的外周血标本,常规提取基因组DNA,应用高分辨染色体核型分析（400-550带）检测患儿及其父母的染色体数目及结构,微阵列比较基因组杂交技术(array-CGH)筛查患儿的全基因组拷贝数变异,以荧光原位杂交技术（FISH）对异常的基因拷贝进行染色体精确定位和定量。结果 女,2岁,发育迟缓伴孤独症样表现。外侧眼角下垂、内眦赘皮。常规染色体核型检查（320带）分别为47,XX,+22和47,XX,+21。高分辨染色体核型分析显示,该患儿携带额外标记染色体（SMC）,核型为47,XX,+mar dn,尚不能确定是否为21/22三体携带者,患儿父亲高分辨率核型染色体分析提示为46,XY,母亲为46,XX,提示患儿携带SMC为新生突变。array-CGH检测显示15q11.2-13.2区域微重复（chr15:22684529-30730543,8.0 Mb,hg19）。FISH验证该SMC来源于15号染色体,由15q11.2-13.2区域二倍体及双着丝粒组成。患儿最终诊断为15q11.2-13.2微重复四倍体综合征。复习文献报道的15q11.2-13.2拷贝数增加病例的临床表型,微重复四倍体综合征的主要表型有智力低下/发育迟缓（100％）、肌张力低下（92.9％）、孤独症/孤独症样表现（71.4％）和癫痫（61.5％）等。结论 15q11.2-13.2微重复四倍体综合征是患儿发生精神发育迟滞伴孤独症的遗传学基础,array-CGH能够快速、准确地检测基因组的微小失衡。     

双侧小睾丸患者的核型分析

目的：探讨男性先天性睾丸发育不全的可能因素。方法：运用人类外周血淋巴细胞常规染色体核型并结合文献进行分析。结果：50个分裂象中有6个是四倍体核型：92，XXYY；余44个是正常核型：46，XY。结论：该男性患者核型溪嵌合体：46，XY／92，XXYY。     

高山红景天同源四倍体诱导与鉴定研究

目的获得高山红景天同源四倍体无性体系。方法秋水仙素诱导种子加倍,通过多次组培再生进行嵌合体分离,采用气孔大小与密度测量、染色体计数和流式细胞学分析进行倍性鉴定。结果秋水仙素质量分数与处理时间对种子萌发率、幼苗死亡率及诱变率均有十分明显的影响,0.2%秋水仙素处理露白种子72 h的萌发率、幼苗死亡率及诱变率分别为18.2%、73.6%、68.7%;倍性变异植株气孔明显增大,气孔密度变小;正常二倍体染色体数目为2n=2x=26,四倍体染色体数为2n=4x=52,发现非整倍体的存在;倍性变异植株经3次再生纯化后获得纯合四倍体无性系,流式细胞学检测无嵌合体存在。结论秋水仙素处理高山红景天种子获得同源四倍体具有可行性。