不同激素配伍对雨生红球藻(Haematococcus pluvialis)细胞生长和虾青素累积的调节作用、藻株差异及应用

利用生长素(NAA、3-IBA)和细胞分裂素(6-BA、kt)两类植物激素,对比研究了其不同配伍对4株雨生红球藻H0、H2、H3和H4细胞生长以及虾青素累积的调节作用.结果表明,尽管在不同株系之间存在一定的差异,但激素明显促进该藻细胞生长和虾青素累积,而对细胞大小没有产生明显影响.激素对红球藻细胞数量的增加主要是靠加快游动细胞阶段无性繁殖过程来实现的:而激素对虾青素含量的提高却是通过增加细胞数量和细胞内虾青素积累的协同作用结果,其中以细胞数量的增加为主.在激素单因素实验中,3-IBA对H0细胞生长增加效果最好,对H2、H3细胞生长增加效果较好的是kt,对H4细胞生长增加效果最明显的是NAA.与空白对照组相比,上述激素处理后细胞生长速度分别提高了1.95、1.54、4.25和1.78倍.经过激素多因素实验,H0、H2、H3和H4藻株的细胞生长增加效果分别是空白组的1.44、2.62、2.52、1.07倍,而虾青素含量分别为空白组的1.09、1.61、1.37、2-35倍.根据4株藻株的实验结果以及综合考虑各激素的市场价格,建议在规模化生产中,采用1.75mg/NAA和4mg/L 3-IBA以提高红球藻的培养效果.     

文蛤(Meretrix meretrix)幼虫发育过程中细胞凋亡和Caspase 功能分析

以文蛤为研究对象,利用TUNEL技术(Terminal-deoxynucleotidyl transferase mediated dUTP Nick End Labeling)检测了文蛤各发育阶段的幼虫中细胞凋亡的部位,利用Caspase原位标记分析了有活性的Caspase在幼虫中的分布情况,用Caspase抑制剂Z-VAD-FMK处理受精后4天和5天的变态前幼虫,同时以抑制剂的有机溶剂DMSO(Dimethyl sulfoxide)作对照,根据其对幼虫变态的影响,分析Caspase在文蛤幼虫变态中的作用.细胞凋亡检测结果显示,幼虫发育过程中发生细胞凋亡的部位主要在壳顶幼虫的面盘,说明细胞凋亡可能是文蛤幼虫变态过程中面盘退化的主要机制;在担轮幼虫至壳顶幼虫中都检测到有活性的Caspase,说明整个幼虫形态变化过程中都有Caspase的参与;用Caspase特异性抑制剂处理变态前幼虫,发现处理组幼虫变态率均显著低于对照组(P<0.05),说明Caspase在变态早期和晚期都有重要作用,同时发现DMSO对幼虫变态有诱导作用,可以在生产中加以利用.     

Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay

Prorocentrum donghaiense is an important harmful algae bloom (HAB) causing creature in China’s seas, and the conventional visual detection can not cope with long-term monitoring and high-throughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay (NPA-SH) was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, ...     

Effects of tributyltin （TBT） on enzyme activity and oxidative stress in hepatopancreas and hemolymph of small abalone, Haliotis diversicolor supertexta

We investigated the effect of tributyltin (TBT) exposure on the concentration of malondialdehyde (MDA) and the activity levels of the superoxide dismutase (SOD), catalase (CAT), and acid and alkaline phosphatase (ACP and AKP) enzymes in the small abalone, Haliotis diversicolor supertexta. We collected samples of the hepatopancreas and hemolymph 2, 6, 24, 48, 96, and 192 h after exposure to 0.35 μg (Sn)/L TBT. In the hepatopancreas, ACP activity was significantly higher in animals exposed to TBT 2, 24, and 96 h post-exposure compared with the control animals. AKP activity was also higher after 2 h, but SOD and CAT activity was unchanged. The concentration of MDA in the hemolymph was significantly higher than the control animals 2 and 6 h post-exposure. In the hemolymph of animals exposed to TBT, ACP activity was significantly lower than in the control animals 192 h post-exposure, whereas AKP activity was significantly lower 2 and 192 h post-exposure. Hemolymph SOD activity and levels of MDA were significantly lower than in the control animals 24 h after exposure but significantly higher after 96 h. Our results demonstrate that exposure to TBT cause rapid changes in ACP and AKP activity as well as altering the concentration of MDA in the hepatopancreas and hemolymph. SOD and CAT do not appear to be involved in the detoxification of TBT in the hepatopancreas of small abalone.     

Effects of iron electrovalence and species on growth and astaxanthin production of Haematococcus pluvialis

To increase the cell concentration and the accumulation of astaxanthin in the cultivation of Haematococcus pluvialis, effects of different iron electrovalencies (Fe²⁺-EDTA and Fe³⁺-EDTA) and species (Fe-EDTA, Fe(OH)_x^32x and FeC₆H₅O₇) addition on cell growth and accumulation of astaxanthin were studied. Results show that different iron electrovalencies have various effects on cell growth and astaxanthin accumulation of H. pluvialis. Compared with Fe³⁺-EDTA, Fe²⁺-EDTA stimulate more effectively the formation of astaxanthin. The maximum astaxanthin content (30.70 mg/g biomass cell) was obtained under conditions of 18 μmol/L Fe²⁺-EDTA, despite the lower cell density (2.3×10⁵ cell/ml) in such condition. Fe³⁺-EDTA is more effective than Fe²⁺-EDTA in improving the cell growth. Especially, the maximal steady-state cell density, 2.9×10⁵ cell/ml was obtained at 18 μmol/L Fe³⁺-EDTA addition. On the other hand, all the various species of iron (EDTA-Fe, Fe(OH)_x^32x, FeC₆H₅O₇) are capable to improve the growth of the algae and astaxanthin production. Among the three iron species, FeC₆H₅O₇ performed the best. Under the condition of a higher concentration (36 μmol/L) of FeC₆H₅O₇, the cell density and astaxanthin production is 2 and 7 times higher than those of iron-limited group, respectively. The present study demonstrates that the effects of the stimulation with different iron species increased in the order of FeC₆H₅O₇, Fe(OH)_x^32x and EDTA-Fe. Supported by Xiamen Scientific and Technologic Projects (No. 3052Z20031086), Xiamen University Alumni Association Foundation in Singapore, and the First National College Students Innovative Experimental Project     

Interactions between a cyanobacterial bloom （Microcystis） and the submerged aquatic plant Ceratophyllum oryzetorum Kom

In aquatic ecosystems, macrophytes and phytoplankton are main primary producers, in which macrophyte plays an important role in maintaining clear water state, while phytoplankton often dominates in turbid waterbodies. In the present study, the growth and photosynthetic activity of the submerged aquatic plant Ceratophyllum oryzetorum Kom. in different cell densities of cyanobacterial bloom are studied. The results show that the plant length and fresh mass of C. oryzetorum are promoted by low cyanobacterial cell densities. Medium and high cyanobacterial cell densities, on the contrary, act as inhibitory. Furthermore, the photosynthetic activity of C. oryzetorum is strongly inhibited by high cyanobacterial cell densities. To a certain extent, the growth of cyanobacteria is inhibited by C. oryzetorum, but no significant effect is found in this study.     

文蛤多肽的体外抗癌活性研究

采用硫酸铵沉淀、有机溶剂分离、Sephadex G-25分子筛层析等实验方法,从文蛤肉中提取了一种低分子量的多肽,命名为Mer2．本文以溴化二苯偶氮盐（MTT）法检测Mer2对体外培养的癌细胞的抑制作用．结果表明Mer2对体外培养的人肝癌细胞株（HepG2）、宫颈癌细胞株（Hela）、胆管癌细胞株（QBC939）、肺癌细胞株（SPC—A-1和LTEP—a-2）的生长均有很强的抑制作用,且抑制效果随着Mer2含量的增高和处理时间的延长而增强,证明Mer2具有广谱的抗癌活性．其中Mer2对人肝癌HepG2细胞株抑制作用最为显著,光学显微镜观察经Mer2细胞培养液处理后的细胞形态发生明显的改变,流式细胞仪实验的结果表明处理后的细胞周期发生明显的改变,并在G0／G1期前出现凋亡峰．     

乌龟红血细胞发生研究

通过对乌龟骨髓、脾脏、肝脏等组织涂片的观察研究 ,发现骨髓是乌龟红细胞主要的造血器官 ;红血细胞的发育过程大致经过三个阶段 ,即原始阶段、幼稚阶段、成熟阶段。着重描述了各阶段红血细胞的形态特征 ,并对乌龟红血细胞的发育及命名等问题作了初步探讨     

EBV感染相关性肿瘤性病变及影像学特点

Epstein-Barr病毒（EBV）属γ疱疹病毒,具有嗜淋巴细胞性,EBV是人类感冒病毒群中常见的成员,也是第一个被发现的人类肿瘤病毒。EBV感染主要通过呼吸道分泌物及唾液感染口,B淋巴细胞和上皮细胞是EBV宿主细胞。EBV首次感染常发生于幼年及儿童期。EBV相关性病变常见的包括传染性单核细胞增多症、嗜血细胞综合征,慢性慢性活动性EBV感染、EBV感染相关性自身免疫性疾病。EBV感染还可以引起感染细胞的增殖性病变,如各种良性淋巴增殖性病变,及伯基特淋巴瘤（BL）、霍奇金淋巴瘤（HL）、T/自然杀伤（NK）细胞淋巴瘤等恶性淋巴瘤,还可发生鼻咽癌、胃癌等上皮源性恶性肿瘤。本文对儿童常见的EBV感染相关性肿瘤性病变及影像学表现予以综述。      

春季养生ABC

春节过后,春天的脚步就一天天走近了。每年春天,各大医院的门诊部内往往人满为患,鼻炎、流感、肺炎、麻疹、心脏病、精神疾病……一时之间众症齐发,因此有人把春季戏称为"多病之春"。医学专家指出,春季是冷暖空气频繁交汇的时期,天气多变,忽冷忽热,若不注意健康保养,很容易患上流行疾病。因此,春季养生应以预防疾病为主。溃疡病春季机体代谢增高、胃液增加,凡此种种,会引起胃酸分泌增加,从而引起或诱发溃疡病。溃疡病人应合理膳食,劳逸结合,保证睡眠,防寒