Ecological notes of the alien species Godiva quadricolor (Gastropoda: Nudibranchia) occurring in Faro Lake (Italy)

The first record from Sicily of the introduced facelinid nudibranch Godiva quadricolor allowed the detection of trophic relationships with the polycerid Polycera hedgpethi, another non-native nudibranch, and with two bryozoan species, namely the naturalized Cheilostomatida Bugula neritina and the cryptogenic Ctenostomatida Amathia verticillata. The settlement of both nudibranchs was presumably promoted by a trophic shift of P. hedgpethi from the natural prey B. neritina towards the largely available and not exploited A. verticillata. This short food web, without evident links with native fauna and having G. quadricolor as the top predator, is described. A DNA barcoding approach was used to confirm the identity of this facelinid species and to explore the possible genetic divergence occurring among the samples analysed.     

基于DNA-AuNCs的荧光传感新方法灵敏检测胰蛋白酶活性

以DNA模板金纳米簇(DNA-AuNCs)作为荧光探针,发展了一种灵敏检测胰蛋白酶活性的荧光分析新方法.在胰蛋白酶存在条件下,牛血清白蛋白水解成多肽片段,释放出游离的半胱氨酸残基.半胱氨酸残基与金纳米簇通过Au-S键形成非荧光的配合物,导致金纳米簇的荧光强度显著降低.该方法对胰蛋白酶的线性检测范围为0.1～2.0mg/L,检出限为20μg/L(R_(SN)=3).此外,该方法被成功应用于人血清样品中胰蛋白酶含量的测定.     

Comparative genetic differentiation study of three coexisting mangrove crabs in western Atlantic

ABSTRACT

A multispecies approach may reveal the factors influencing the genetic differentiation of coexisting species along a wide geographic area. Our aim was to compare the genetic differentiation of mangrove crabs coexisting along the western Atlantic in order to verify if there are common barriers, using two mitochondrial DNA markers to quantify genetic differentiation, variance and diversity. In addition, we included a mismatch distribution to check demographic history. Our data revealed that species with similar pelagic larval duration had either high genetic differentiation or the absence of genetic structure. These results can be explained by factors that contribute to genetic differentiation, such as the presence of large estuarine areas (acting as barriers), ocean currents, and larval behaviour. Also, historical events that promoted the isolation of some areas in the past, such as glacial cycles during the Pleistocene, could have caused the observed high levels of genetic divergence in some species.     

大草履虫总DNA的提取方法比较

快速而稳定地提取大草履虫的基因组DNA是进行后续分子生物学研究的前提.文章通过比较传统SDS法、CTABⅠ法和CTABⅡ法等提取大草履虫DNA的效果,进一步优化提取方法,获得快速稳定地提取大草履虫基因组DNA的方法.结果表明:用CTAB I法提取的DNA浓度低,杂质较多;CTABII提取的DNA电泳时检测不出条带;而SDS法提取的DNA在电泳时带型较整齐,无降解,且DNA的得率和纯度较高,但仍有蛋白质污染.针对蛋白质的去除,用SDS-蛋白酶K法和SDS-NaAc法来提取DNA,经过试验发现这2种方法都能够很好地去除蛋白质,所获DNA样品的纯度和得率都能用于进一步分子试验,而SDS-NaAc法更经济适用.     

氯化1-辛基-3-甲基咪唑对EMT6细胞的毒性及其DNA损伤作用

研究了氯化1-辛基-3-甲基咪唑([C8mim][Cl])对EMT6细胞的毒性大小及其可能的遗传机制.不同浓度(0.06、0.25、1.00mmol·L-1)的[C8mim][Cl]对EMT6细胞染毒12h,WST-1比色法检测了细胞活力,ELISA方法检测了Bcl-2蛋白的表达,Hoechst 33342染色检测了细胞核形态的变化,单细胞凝胶电泳(SCGE)检测了细胞DNA的损伤,流式细胞仪检测了细胞周期和细胞DNA的含量.结果显示,经[C8mim][Cl]染毒后,EMT6细胞活力下降,并且呈剂量依赖关系.当[C8mim][Cl]浓度高于0.25mmol·L-1时,与对照相比,差异显著.[C8mim][Cl]染毒使Bcl-2蛋白表达下调,引起了细胞核形态改变,造成了DNA的断裂损伤和含量下降,诱导了细胞凋亡.从而可以得出结论,DNA损伤参与了[C8mim][Cl]诱导的细胞凋亡.     

光谱法研究卟啉-蒽醌化合物及其金属锌配合物与DNA的相互作用

用光谱法研究以二肽链连接的卟啉-蒽醌化合物及其金属锌配合物与DNA的相互作用.结果表明:卟啉-蒽醌化合物及其金属锌配合物与DNA发生外部结合.由紫外-可见光谱滴定数据进行拟合计算出卟啉-蒽醌化合物及其金属锌配合物与DNA相互作用的结合常数分别为2.2×105(mol/L)-1和6.7×105(mol/L)-1.     

铜-吡唑啉酮-2,6-吡啶二羧酸配合物的合成、表征及其性质研究

以氯化铜、1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮和2,6-吡啶二羧酸为原料,制备了一个新型的三元配合物,通过元素分析、红外光谱、紫外光谱、X射线粉末衍射、热重-差热分析、光电子能谱分析及TEM等手段对配合物进行了表征,确定了配合物的化学组成可能是Na[Cu(PMBP)(PDA)].抗菌实验结果表明,配合物对大肠杆菌、金黄色葡萄球菌具一定的抑制作用.采用紫外光谱法和荧光光谱法初步研究了配合物与CT-DNA的作用方式,结果表明:配合物可能是以插入模式与DNA结合的.     

ChiraSac Study on Chiral Spectroscopy and Photobiology

Weak interactions of molecules with solvents and/or environments are of crucial importance in material science and biology,but rather difficult to investigate quantitatively.Circular dichroism(CD)spectra reflect sensitively the conformational structures of chiral molecules,their(weak)interactions with solvents and/or proteins,etc.The SAC-CI method gives their CD spectra very reliably.     

低能N+注入凤仙花的变异检测

以低能N 注入凤仙花(Impatiens balsaminaL)种子后获得了高茎、矮茎2个变异品系.对其进行过氧化物同工酶(POD)检测的结果表明,2个变异品系叶片的POD分子大小、表达强度和条带数目与对照相比都发生了一定变化.随机扩增多态性DNA(random amplified polymorphic DNA,RAPD)分析结果也表明变异品系DNA链的脱氧核苷酸序列发生了变异,从25个随机引物中筛选出了9个具有多态性.实验证明适当剂量的低能N 注入能够在基因水平引起凤仙花的变异,为花卉产业的发展提供了一种遗传育种手段.     

Role of Ppt1 in multiple stress responses in Candida albicans

To study the function of CaPptl, we deleted PPT1 gene from the Candida albicans genome by sequentially replacing the entire coding region with the selectable markers ARG4 and HIS1. The results showed that the deletion of Pptl did not affect the hyphal formation of C. albicans under serum induction and caused enhanced sensitivity to DNA damage, Calcofluor white and salt- induced stress. We also found that Pptl was not required for the phenotypic response of cells treated with the genotoxins, methylmethane sulfonate and hydroxyurea. Flow cytometric analyses indicated that pptlA cells and wild-type cells showed similar G2/M arrest profiles when exposed to DNA damage stress. Pptl was not required for the activation of the DNA damage response pathway, as indicated by normal phosphorylation of Rad53 and Rfa2 in pptlA cells under DNA damage stress. We suggest that Pptl plays important roles in response to various stress conditions in C. albicans.