热冲击和加氯后亚热带海区浮游植物细胞数量的动态变化

 近年来, 随着电厂在河口和港湾等生态脆弱区和敏感区的急剧增多, 电厂冷却系统热冲击和加氯对浮游生物造成的伤害已成为沿海地区非常严峻的生态安全问题。为探明冷却系统升温和加氯联合作用对亚热带海区浮游植物的影响程度, 针对滨海电厂的实际运作情况, 在室内对采自浙江省乐清湾海域的四季浮游植物进行了不同水平的热冲击和加氯胁迫, 并观察了这些浮游植物细胞数量在15 d内的动态变化。结果表明, 热冲击、加氯和季节均显著影响浮游植物细胞数量的恢复(p＜0.001), 其中, 加氯的影响最大, 季节次之, 热冲击影响最小, 但热冲击增强了氯对浮游植物的毒性。自然水温越高、升温幅度越大, 细胞数量恢复越慢。春、秋、冬季自然水温较低时, 升温4～12 ℃后, 细胞数量仅需1～6 d即可恢复到对照组水平; 夏季自然水温较高, 升温4～8 ℃后, 细胞数量需4～9 d恢复到对照组水平, 但升温12 ℃后, 细胞数量在15 d内未能恢复到对照组水平。加氯浓度越高, 细胞数量恢复越慢。加氯1.0～1.8 mg•L^−1后, 浮游植物生长虽受影响, 但大多能在15 d内恢复; 而加氯5.6 mg•L^−1后, 其生长受到完全抑制, 细胞数量在15 d内未恢复到对照组水平。     

Nicotinic autoreceptor function in rat brain during maturation and aging: possible differential sensitivity to organophosphorus anticholinesterases

Acetylcholine (ACh) release is modulated pre-synaptically by both muscarinic and nicotinic receptor-mediated processes. While muscarinic autoreceptors inhibit ACh release, nicotinic autoreceptors enhance ACh release and thus disruption of these processes could potentially affect cholinergic toxicity following exposure to anticholinesterases. Marked age-related differences in sensitivity to some organophosphorus (OP) anticholinesterases have been reported. We compared nicotinic autoreceptor function (NAF) during maturation and aging and evaluated its potential modulation by the common OP insecticide, chlorpyrifos (CPF). Cortical synaptosomes were pre-loaded with [3H]choline, superfused (0.6 ml/min) with physiological buffer and [3H]ACh release was evoked with potassium (KCl, 9 mM), with or without co-addition of exogenous ACh to stimulate nicotinic autoreceptors. Fractions of perfusate were subsequently collected and area under the curve (AUC) for [3H] was analyzed by scintillation counting. The difference in evoked release due to co-addition of exogenous ACh was defined as NAF. Under these conditions, atropine (ATR, 0.1 microM) appeared requisite for NAF; thus this muscarinic antagonist was subsequently added to all perfusion buffers. In synaptosomes from adult tissues, exogenous ACh (3-100 microM) significantly increased release in a concentration-dependent manner. The nicotinic antagonist mecamylamine (MEC, 100 microM) substantially reduced the potassium-evoked release elicited by co-addition of ACh (10 microM). Interestingly, the nicotinic agonists nicotine (NIC) and dimethylphenylpiperazinium (DMPP; 0.1-10 microM) had no effect on release. The active metabolite of CPF (i.e. chlorpyrifos oxon (CPO), 1-10 microM) inhibited NAF in vitro. Maturation-related expression of NAF was noted (AUC with co-addition of 10 microM ACh: 7-day rats, 7+/-6; 21-day rats, 44+/-6; 90-day rats, 196+/-37; 24-month rats, 173+/-52). NAF was substantially reduced (67-91%) 96 h after maximum tolerated dosages of CPF in adult and aged rats (279 mg/kg, sc) but not in juveniles (127 mg/kg, sc), even though AChE inhibition was similar among the age groups (>80%). Together these data suggest that NAF is differentially expressed during maturation and that this neuromodulatory process may be selectively altered by some OP insecticides, potentially contributing to age-related differences in response to AChE inhibitors. As NAF has been postulated to be activated under conditions of 'impaired' cholinergic function, selective alteration of this pre-synaptic process by OP anticholinesterases may be also important in age-related conditions associated with cholinergic hypofunction.     

4种饵料对小火蚁工蚁的诱集效果比较

小火蚁Wasmannia auropunctata Roger被世界自然保护联盟（IUCN）列为最具危害性的100种入侵物种之一。2022年1月份,小火蚁首次被发现入侵中国大陆,开发小火蚁的监测技术对于摸清该种入侵蚂蚁的发生程度与分布范围有重要意义。本文测定了火腿肠、花生酱、花生油和蜂蜜等4种饵料对小火蚁的诱集效果,并对不同生境小火蚁数量进行了调查。室内试验中火腿肠诱集效果最好,花生酱和花生油次之,蜂蜜最差。在野外试验中,花生酱和火腿肠的诱集效果最佳,放置30 min的诱集数量与60 min时无显著差异,并且饵料摆放瓶口处能诱集到更多工蚁,上午和下午更适宜进行诱集试验。利用花生酱进行野外调查发现小火蚁在山腰、山脚、屋内、田埂和路边等生境中均有分布。以上结果为进一步开展小火蚁疫情的调查提供了参考。     

Functional rs6265 polymorphism in the brain-derived neurotrophic factor gene confers protection against neurocognitive dysfunction in posttraumatic stress disorder among Chinese patients with hepatocellular carcinoma

Posttraumatic stress disorder (PTSD) is a psychiatric disorder that plagues trauma survivors. Evidence shows that brain-derived neurotrophic factor (BDNF) may be involved in the occurrence and development of PTSD. Here we tried to demonstrate whether BDNF gene polymorphisms are correlated with neurocognitive function following PTSD in patients with hepatocellular carcinoma (HCC). This study included 102 patients with HCC complicated with PTSD, 146 HCC patients, and 152 healthy volunteers. Initially, we evaluated the neurocognitive function of the study subjects. Next, we measured BDNF G11757C and rs6265 polymorphisms by polymerase chain reaction-restriction fragment length polymorphism. The correlation of BDNF polymorphisms and BDNF level with HCC complicated with PTSD was evaluated. The results revealed that HCC complicated with PTSD showed decreased serum BDNF level and Mini-mental state examination (MMSE) score. Serum BDNF level of HCC and HCC complicated with PTSD was positively correlated with MMSE score. GA + AA allele and A allele of rs6265 increased the risk of PTSD among patients with HCC. GA and AA genotypes of rs6265 were correlated with the decreased MMSE score of HCC complicated with PTSD. Haplotype GA of rs6265 and G11757C increased the risk of PTSD for HCC, while haplotype CG decreased this risk. Lastly, the logistic regression analysis suggested that low BDNF level was a contributor to HCC complicated with PTSD, while GG genotype of rs6265 served as a protective factor. Collectively, this study defines the GG genotype of BDNF rs6265 polymorphism as a protector to HCC complicated with PTSD. In addition, these results provided a promising target for PTSD prevention in patients with HCC.     

Baicalein Inhibits Progression of Gallbladder Cancer Cells by Downregulating ZFX

Baicalein, a widely used Chinese herbal medicine, has multiple pharmacological activities. However, the precise mechanisms of the anti-proliferation and anti-metastatic effects of baicalein on gallbladder cancer (GBC) remain poorly understood. Therefore, the aim of this study was to assess the anti-proliferation and anti-metastatic effects of baicalein and the related mechanism(s) on GBC. In the present study, we found that treatment with baicalein induced a significant inhibitory effect on proliferation and promoted apoptosis in GBC-SD and SGC996 cells, two widely used gallbladder cancer cell lines. Additionally, treatment with baicalein inhibited the metastasis of GBC cells. Moreover, we demonstrated for the first time that baicalein inhibited GBC cell growth and metastasis via down-regulation of the expression level of Zinc finger protein X-linked (ZFX). In conclusion, our studies suggest that baicalein may be a potential phytochemical flavonoid for therapeutics of GBC and ZFX may serve as a molecular marker or predictive target for GBC.     

Null mutation of peroxisome proliferator-activated receptor-interacting protein in mammary glands causes defective mammopoiesis

To investigate the role of nuclear receptor coactivator peroxisome proliferator-activated receptor-interacting protein (PRIP) in mammary gland development, we generated a conditional null mutation of PRIP in mammary glands. In PRIP-deficient mammary glands, the elongation of ducts during puberty was not affected, but the numbers of ductal branches were decreased, a condition that persisted long after puberty, indicating that the potential of ductal branching was impaired. During pregnancy, PRIP-deficient mammary glands exhibited decreased alveolar density. The lactating PRIP-deficient glands contained scant lobuloalveoli with many adipocytes, whereas the wild type glands were composed of virtually no adipocytes but mostly lobuloalveoli. As a result, PRIP mammary-deficient glands could not produce enough milk to nurse all the pups during lactation. The ductal branching of mammary glands in response to estrogen treatment was attenuated in PRIP mutant glands. Whereas the proliferation index was similar between wild type and PRIP-deficient glands, increased apoptosis was observed in PRIP-deficient glands. PRIP-deficient glands expressed increased amphiregulin, transforming growth factor-alpha, and betacellulin mRNA as compared with wild type glands. The differentiated function of PRIP-deficient mammary epithelial cells was largely intact, as evidenced by the expression of abundant beta-casein, whey acidic protein (WAP), and WDNM1 mRNA. We conclude that PRIP is important for normal mammary gland development.     

三甲基苯基磷酸酯对神经毒性酯酶的抑制及其酶促动力学分析

以可使人和敏感动物产生迟发性神经毒性的有机磷化合物三甲基苯基磷酸酯（TOCP）为测试药物,研究其在体外对成年产卵来航母鸡不同神经组织神经毒性酯酶（NTE）活性抑制的敏感性及其抑制的动力学．结果表明,外周神经NTE对于TOCP的抑制比中枢神经NTE敏感得多．TOCP对鸡脑、脊髓和坐骨神经中NTE抑制的I50值．分别为：1．9323、2．3950和0．0035mmol／L．NTE酶促动力学研究显示,鸡脑NTE催化分解底物戊酸苯酯（PV）的Vmax为62．10nmol·min-1·mg-1,Km为0．92mmol／L．TOCP对鸡脑NTE的抑制属竞争性抑制类型,并有"底物抑制"现象．     

一种快速检测分离溶藻细菌方法的初探

传统的细菌培养基对铜绿微囊藻具有毒性作用。会大大影响溶藻细菌的筛选效率和准确性。通过基本培养基各成分对铜绿微囊藻DS的作用研究发现,培养基中的葡萄糖成分对藻有抑制作用,并且这种抑制作用与培养基中的葡萄糖浓度密切相关,当培养基中葡萄糖的浓度在0．1～0．4g/L时,藻细胞生长受到抑制,当用柠檬酸三钠取代葡萄糖后,铜绿微囊藻在改良后的培养基中生长正常,与对照组相比无显著性差异(P＜0．05)。用改良的培养基富集水样中的溶藻微生物,并用此培养液直接感染宿主藻,一周内即可初步快速检测是否含有溶藻细菌。此种方法既排除了培养基的干扰因素,又迅速增加了溶藻细菌的生物量,并可大量收集细菌分泌的胞外物质,为溶藻细菌尤其以分泌物质溶藻的细菌的初步筛选提供了一条快捷、有效的途径。