The sea urchin embryo, an invertebrate model for mammalian developmental neurotoxicity, reveals multiple neurotransmitter mechanisms for effects of chlorpyrifos: therapeutic interventions and a comparison with the monoamine depleter, reserpine

Lower organisms show promise for the screening of neurotoxicants that might target mammalian brain development. Sea urchins use neurotransmitters as embryonic growth regulatory signals, so that adverse effects on neural substrates for mammalian brain development can be studied in this simple organism. We compared the effects of the organophosphate insecticide, chlorpyrifos in sea urchin embryos with those of the monoamine depleter, reserpine, so as to investigate multiple neurotransmitter mechanisms involved in developmental toxicity and to evaluate different therapeutic interventions corresponding to each neurotransmitter system. Whereas reserpine interfered with all stages of embryonic development, the effects of chlorpyrifos did not emerge until the mid-blastula stage. After that point, the effects of the two agents were similar. Treatment with membrane permeable analogs of the monoamine neurotransmitters, serotonin and dopamine, prevented the adverse effects of either chlorpyrifos or reserpine, despite the fact that chlorpyrifos works simultaneously through actions on acetylcholine, monoamines and other neurotransmitter pathways. This suggests that different neurotransmitters, converging on the same downstream signaling events, could work together or in parallel to offset the developmental disruption caused by exposure to disparate agents. We tested this hypothesis by evaluating membrane permeable analogs of acetylcholine and cannabinoids, both of which proved effective against chlorpyrifos- or reserpine-induced teratogenesis. Invertebrate test systems can provide both a screening procedure for mammalian neuroteratogenesis and may uncover novel mechanisms underlying developmental vulnerability as well as possible therapeutic approaches to prevent teratogenesis.     

A new cytolytic protein from the sea anemone Urticina crassicornis that binds to cholesterol- and sphingomyelin-rich membranes

A new pore-forming cytolytic protein was isolated from the Northern red sea anemone, Urticina crassicornis. Its biochemical properties were characterized and partial N-terminal amino acid sequence was determined. The cytolysin, named UcI, has a molecular mass of around 30 kDa and lacks phospholipase A₂ activity. UcI lyses bovine erythrocytes at nanomolar concentrations. Hemolysis is a result of a colloid-osmotic shock caused by the opening of toxin-induced ionic pores and can be prevented by osmotic protectants of size >600 Da. The functional radius of an average pore was estimated to be about 0.66 nm. A more detailed study of the cytolytic activity of UcI was performed with lipid vesicles and monolayers. The toxin binds to monolayers and efficiently permeabilizes small lipid vesicles composed of sphingomyelin and cholesterol. However, the cytolytic activity is not prevented by preincubation with either pure cholesterol or sphingomyelin dispersions. We conclude that the presence of both sphingomyelin and cholesterol, key components of lipid rafts, greatly enhances toxin binding to membranes and probably facilitates pore formation. Alignment of the toxin partial amino acid sequence with sequences of cytolysins belonging to the actinoporin family reveals no sequence homology. We conclude that partial sequence of UcI resembles only the N-terminal part of UpI, a cytolytic protein isolated from a related sea anemone species, Urticina piscivora. The two proteins most probably belong to a separate family of sea anemone cytolysins that are worthy of further characterization.     

花刺参中两个新的四环三萜化合物

目的从花刺参Stichopus variegatus中分离活性皂苷类成分。方法将花刺参体内得到的总皂苷溶于吡啶-2-二氧六环(1︰1)的混合液中,130℃加热2.5 h,应用多种色谱技术对回流产物进行分离纯化,得到2个三萜皂苷类化合物。结果应用现代光谱技术(2D-NMR和ESI-MS)和化学方法鉴定其结构,分别为3-O-[β-D-吡喃木糖(1→2)-4′-O-磺酸钠-β-D-吡喃木糖]-海参烷-9-烯-3β,12α,17α,25β-四醇,命名为花刺参苷A(variegatuside A,1);3-O-β-D-吡喃木糖-16β-乙酰氧基-海参烷-9-烯-22,25-环氧-3β,12α,17α-三醇,命名为花刺参苷B(variegatuside B,2)。结论化合物1和2均为新化合物。     

对海参糖胺聚糖抗氧化性的研究

目的研究海参糖胺聚糖的抗氧化性。方法以K3[Fe（CN）6]为模型,测定海参糖胺聚糖的还原能力。利用邻苯三酚自氧化产生超氧阴离子自由基（·O^2-）且在320nm处有最大吸收,测定海参糖胺聚糖对羟自由基（·OH^-）和超氧阴离子自由基（·O^2-）的清除能力。结果海参糖胺聚糖有较强的还原力,对羟自由基和超氧阴离子自由基的清除能力与浓度成量效关系,有良好的清除羟自由基和超氧阴离子自由基的作用。结论海参糖胺聚糖具有良好的抗氧化作用。     

我国南海海上卫勤保障现状与对策

目的提升南战区海上卫勤保障能力,更好履行捍卫祖国主权的神圣使命。方法对我国南海卫勤保障的现状进行分析,对外军海上卫勤保障经验进行借鉴。结果提出了建立协调的卫勤保障体制;制订全面的卫勤保障计划;建设不同的卫勤保障队伍;实施全面的卫勤训练程序;制订完整的海上救治方法;掌握完美的海上救治技巧;提高抗颠簸的海上适应能力;更新可靠的海上救护装备＂八项＂对策。结论现代海上平、战时卫勤保障能力的提升,是南战区卫勤保障亟待研究的重要内容。     

Safety and healing efficacy of Sea buckthorn (Hippophae rhamnoides L.) seed oil on burn wounds in rats

The present investigation was undertaken to determine the safety and efficacy of supercritical CO₂-extracted Hippophae rhamnoides L. (Sea buckthorn) (SBT) seed oil on burn wound model. SBT seed oil was co-administered by two routes at a dose of 2.5 ml/kg body weight (p.o.) and 200 μl (topical) for 7 days on experimental burn wounds in rats. The SBT seed oil augmented the wound healing process as indicated by significant increase in wound contraction, hydroxyproline, hexosamine, DNA and total protein contents in comparison to control and reference control treated with silver sulfadiazine (SS) ointment. Histopathological findings further confirmed the healing potential of SBT seed oil. SBT seed oil treatment up-regulated the expression of matrix metalloproteinases (MMP-2 and 9), collagen type-III and VEGF in granulation tissue. It was observed that SBT seed oil also possesses antioxidant properties as evidenced by significant increase in reduced glutathione (GSH) level and reduced production of reactive oxygen species (ROS) in wound granulation tissue. In acute and sub-acute oral toxicity studies, no adverse effects were observed in any of the groups administered with SBT seed oil. These results suggest that the supercritical CO₂-extracted Sea buckthorn seed oil possesses significant wound healing activity and have no associated toxicity or side effects.     

Balneotherapy in dermatology

Balneotherapy and spa therapy emerged as an important treatment modality in the 1800s, first in Europe and then in the United States. Balneotherapy involves immersion of the patient in mineral water baths or pools. Today, water therapy is being practiced in many countries. Examples of unique and special places for balneotherapy are the Dead Sea in Israel, the Kangal hot spring in Turkey, and the Blue Lagoon in Iceland. Bathing in water with a high salt concentration is safe, effective, and pleasant for healing and recovery. This approach needs no chemicals or potentially harmful drugs. There are almost no side effects during and after treatment, and there is a very low risk to the patient's general health and well-being. Mineral waters and muds are commonly used for the treatment of various dermatologic conditions. The major dermatologic diseases that are frequently treated by balneotherapy with a high rate of success are psoriasis and atopic dermatitis. The mechanisms by which broad spectrums of diseases are alleviated by spa therapy have not been fully elucidated. They probably incorporate chemical, thermal, mechanical, and immunomodulatory effects. The major importance of balneotherapy and spa therapy both individually and as complements to other therapies lies in their potential effectiveness after standard medical treatments have failed to give comfort to these patients.     

南海驻礁人员胃肠道疾病患病率及干预效果分析

目的探讨南海驻礁人员干预前后胃肠道疾病患病率的变化,完善防治方案。方法在干预前后采用统一的现场一对一问卷调查,内容包括胃肠道疾病界定、患病情况及致病危险因素(含6类84项因素)。结果干预前,胃肠道疾病患病率67.4,其中确诊病例6.9,临床病例60.5;干预后,胃肠道疾病患病率25.2,其中确诊病例4.3,临床病例20.9。干预后患病率和临床病例下降显著(P<0.001)。致病危险因素,包括在南海工作时间、进食速度、是否进食规律,是否喜食生冷、刺激性食物,是否饮酒、喝浓茶,精神紧张及服用相关药物史等。结论共同的综合性干预措施和具体的针对性干预措施相结合,能显著降低南海驻礁人员胃肠道疾病患病率。