LPS致肝细胞损伤模型的建立研究

[目的]探索LPS体外致人ChangLiver细胞损伤模型的建立方法和意义。[方法]分别用20．40、60、80、1130μg／ml浓度的LPS作用ChangLiVer细胞24h,采用MTF法检测LPS对ChangLivet细胞存活率的影响,分别测定ChangLiver细胞上清中谷草转氨酶（AST）、谷丙转氨酶（ALT）、碱性磷酸酶（ALP）、γ-谷氨酰转肽酶（γ-GT）、乳酸脱氢酶（IJDH）的活性,并通过Hoechst33258荧光染色观察用药24h后ChangLiver细胞形态的变化。[结果]80和100u晷／ml浓度的LPS作用后ChangLiver细胞存活率显著性降低,胞外AST、ALT、ALP、γ-GT、LDH酶活性升高,细胞数目减少,细胞形态发生改变,呈现细胞核固缩等细胞凋亡现象。（结论l用80μg/ml的LPS与ChangLiver细胞共培养24h,可以建立理想的体外肝细胞损伤模型。     

家猪染色体的Q—分带研究

本文采用QFH显带法,对杜洛克、巴克夏和关中黑猪的Q-分带带型作了较为详细的研究。结果表明,不经BUdR预处理而直接用Hoechst 33258进行分,猪的每一条染色体均能显示出重现性良好的特征性荧光带——QFH带;QFH带与QFQ带带型基本一致,且以QFH带纹较精细。同时,就QFH带对着丝粒异染色质的鉴定作了初步探讨。     

HMC毒素诱导玉米同核C、N细胞质细胞凋亡的荧光显微观察

[目的]研究玉米小斑病菌C小种毒素(HMC-toxin)诱导同核异质体玉米的离体根冠细胞发生凋亡的差异性及凋亡规律.[方法]采用吖啶橙(AO)与溴化乙啶(EB)荧光复染以及Hoechst 33258荧光染色的方法检测.[结果]HMC毒素诱导根冠细胞发生凋亡,出现凋亡小体与染色体边集形态特征.在3种毒素浓度、3种处理时间下,Mo17-C的根冠细胞死亡率均高于Mo17-N.采用AO与EB复染方法,在150μg·mL<'-1>HMC毒素处理7 h时,M017-C细胞凋亡率达最高值,为68.7%,而Mo17-N仅为29%;经Hoechst 33258染色后,在150μg.mL<'-1>HMC毒素处理下,Mo17-C也于7 h时达最大凋亡率,为57.3%,而Mo17-N为27.7%.[结论]在毒素"伤害"细胞致死过程中,C细胞质的细胞死亡率远高于N细胞质;在"诱导"细胞凋亡程序中,C细胞质的细胞凋亡率也远高于N细胞质的.凋亡率随诱导浓度和诱导时间的增加而增加.AO、EB复染与Hoechst 33258染色相比,两者细胞凋亡率接近,准确度均高,图像清晰,且费用相当,但前者可以区分早期和晚期凋亡细胞而后者不能区分.     

Determination of DNA content of whole fish

ABSTRACT:   The DNA content of whole fish from 31 different North Atlantic fish species was determined. Sample preparation was performed on board the fishery research vessel 'Walter Herwig III' directly after catch and sorting. Up to three homogenates were prepared of each 10 specimens per species by mincing the whole fish. The homogenates were heated to destroy nuclease activity, and then stored at frozen temperature until being analyzed in the laboratory. Measurement of DNA content was carried out using the DNA specific fluorescent dye Hoechst 33258 (Serva Biochemica, Heidelberg, Germany). Matrix effects as light scattering and quenching could be estimated by use of standard addition of calf thymus DNA. DNA contents were referred to dry weight of sample material, and ranged from 570 µg to 3500 µg/g dry weight of homogenate. The coefficient of variation did not exceed 25% of mean for one species; coefficient of variation for all investigated species did not exceed 30% of mean, which was 1020 µg/g dry weight.