海洋生物活性肽及其生物活性研究进展

概述存在于海绵、海鞘等海洋低等生物和海洋鱼贝类中的生物活性肽，以及这些活性肽的抗肿瘤、抗菌、抗高血压及抗氧化等生物活性的研究进展。     

中药海藻及数种同属植物的药理作用

对中药海藻海蒿子、羊栖菜及马尾藻科植物匐枝马尾藻、半叶马尾藻、鼠尾藻、铜藻和海黍子进行了药理研究。结果表明:7种海藻的LD_(50)>40g/kg;抗血小板聚集实验仅海黍子表现出较弱的抗凝活性(抑制率20.3％);抗肿瘤试验半叶马尾藻和匐枝马尾藻对小鼠S_(180)实体瘤抑制率分别为55.7％、53.1％;免疫药理实验海蒿子总多糖使小鼠肝脾的重量显著增加,胸腺增长受到显著抑制;海蒿子总多糖和羊栖菜总多糖对单核巨噬细胞的吞噬功能无显著作用。     

几类重要的海洋抗肿瘤药物研究进展

目前对海洋抗肿瘤药物的研究已经成为全世界普遍关注的热点。近年来，苔藓抑素、ecteinascidin-743、海兔毒肽、膜海鞘素、psammaplin、软海绵素B等六类化合物的研究取得了较大进展。本文综述这几类海洋抗肿瘤药物及其衍生物的研究进展，并探讨海洋抗肿瘤药物发展的趋势。     

海鞘药理活性研究概况

海鞘(ascidians)是一种海洋动物,属于脊索动物门(chordates)、尾索动物亚门(urochordata)、海鞘纲(ascidiacea)。自20世纪80年代以来,从海鞘中发现了许多具有抗病毒、抗肿瘤、抗微生物以及免疫调节等生理活性的物质,海鞘化学成分的研究逐渐成为海洋天然产物研究的热点之一。现就近年来海鞘的药理活性研究概况作一综述。     

美洲大蠊多肽的药理作用研究进展

活性多肽是美洲大蠊中主要的药用成分,具有广泛的药理活性。近年来,相关领域的学者陆续发现了来源于美洲大蠊的单组分活性多肽,如periplanetasin-2、periplanetasin-4、美洲大蠊防御素（PaDefensins）、periplanetasin-5、Pa-THY1、短神经肽（sNPF）。对美洲大蠊多肽的抗微生物作用、抗肿瘤作用、促伤口愈合作用和神经调节作用进行了综述,以期为美洲大蠊多肽类药物的筛选、结构改造以及新药开发提供参考。     

群海绵属化学成分及生物活性研究进展

目的 对Agelas 属海绵化学成分和生物活性进行研究总结。方法 通过文献调研,对该属海绵代谢产物类型进行分类整理,并对其生物活性进行总结报道。结果 目前报道的Agelas 属海绵主要含有溴吡咯生物碱、萜类生物碱、鞘糖脂、甾醇、类胡萝卜素和脂肪酸等类型的代谢产物,许多具有良好的生物活性,包括抗肿瘤、抗疟、抗微生物、抗组织胺及免疫调节等活性。结论 Agelas属海绵次生代谢产物丰富,类型多样,并具有良好的生物活性,因此有广阔的开发应用前景。本文为该属海绵的进一步化学与生物活性研究开发提供参考。     

海鞘提取药物具有抗肿瘤活性

最近发表于The Lancet Oncology的一篇文献报道，海鞘提取药物trabectedin（ecteinascidinin-743）在某一特定肿瘤超过半数的患者中显示出抗肿瘤活性。     

美洲大蠊提取物对3株人体生殖系统肿瘤细胞的细胞毒性研究

目的通过对美洲大蠊提取物的肿瘤细胞毒性测试,探讨美洲大蠊提取物的抗肿瘤作用。方法美洲大蠊醇提物,通过聚酰胺柱层析分离划段得不同部位,采用MTT法对所得部位进行肿瘤细胞毒性测试。结果有多个部位样品的IC50值小于10mg·mL-1。结论通过样品与对照品细胞毒活性结果比较,表明美洲大蠊提取物中存在具有肿瘤细胞生长抑制作用的物质,值得对其进行进一步的研究。     

美洲大蠊提取物对3株人体呼吸系统肿瘤细胞的细胞毒性研究

目的通过2对美洲大蠊提取物的肿瘤细胞毒性测试,探讨美洲大蠊提取物的抗肿瘤作用。方法美洲大蠊醇提取物,通过聚酰胺柱层析分离划段得不同部位,采用MTT法对所得部位进行肿瘤细胞毒性测试。结果有多个部位样品的IC50值小于10μg/ml。结论通过样品与对照品细胞毒活性结果比较,表明美洲大蠊提取物中存在具有肿瘤细胞生长抑制作用的物质,值得对其进行进一步的研究。     

海鞘脂肪含量及其脂肪酸组成

对烟台渤海湾的柄海鞘和玻璃海鞘的脂肪含量及其脂肪改组成进行了分析，并对其提取工艺进行了研究。结果表明，海鞘中的脂肪以乙醚为溶剂，提取3h较为理想。脂肪总含量，玻璃海鞘为干重的6．16％；柄海鞘的含量为干重的5．02％，其中内囊的含量占10．68％、海鞘皮中的含量为1．14％。气相色谱及色--质谱分析的结果表明，柄海鞘内囊中的不饱和脂肪酸(UFA)占脂肪酸总量的56．44％，其中多不饱和脂肪酸(PUFA)为37．57％，EPA DHA占18．98％；玻璃海鞘中UFA占脂肪酸总量的36．68％，其中PUFA为23．34％，EPA DHA占9．8％。     

Paralytic toxins in a ribbon worm Cephalothrix species (Nemertean) adherent to cultured oysters in Hiroshima Bay, Hiroshima Prefecture, Japan.

In 1998, during the surveillance of the toxicity of various marine fouling organisms in Hiroshima Bay, Hiroshima Prefecture, Japan, specimens of the ribbon worm, "himomushi" Cephalothrix sp. (Nemertean) adherent to the shells of cultured oysters hanging onto floating culture rafts were found to contain toxins which showed strong paralytic action in mice throughout the survey period, February to May. The maximum toxicity (as tetrodotoxin, TTX) was 14,734 MU/g whole body. Attempts were made to identify the paralytic toxins in this worm. The "himomushi" toxin (HMT) was extracted from the worm with 80% methanol acidified with acetic acid and the extract defatted with dichloromethane. The aqueous layer was chromatographed on activated charcoal and the unbound and bound toxic fractions were analyzed by high-performance liquid chromatography and gas chromatography-mass spectrometry. It was rather unexpectedly revealed from these results that HMT was comprised of TTX, 4-epiTTX, anhydroTTX and three unidentified toxins. To our knowledge, this is the first report of the occurrence of toxic organisms, containing a high concentration of TTX, adherent to cultured bivalves such as oysters.     

Acute toxicity and bioaccumulation of tributyltin in tissues of Urolophus jamaicensis (yellow stingray)

Tributyltin oxide (TBTO) is the main constituent of tin-based antifouling marine paint used on the hulls of ships to prevent the growth of fouling organisms. TBTO was shown to be hazardous to nontarget organisms. The stingray, Urolophus jamaicensis, may represent the ideal study organism for the adverse effects of TBTO to elasmobranches. This study investigated the toxicity and accumulation of tin in the gill tissue of the stingray U. jamaicensis after acute exposure to TBTO. This work demonstrates the alterations in the morphological architecture of the gill using electron and light microscopy, the induction of stress proteins, and peroxidative damage in response to tributyltin (TBT) exposure. A captured population of U. jamaicencis was housed in isolated, static tank systems. After a minimum 30-d acclimation period, the animals were exposed to one of 5 experimental doses of TBTO (4 microg/L, 2 microg/L, 1 microg/L, 0.5 microg/L, or 0.05 microg/L). A sixth group served as a control population. At 3h following treatment, animals were sacrificed and gill tissue was extracted, processed, and stored for analysis. Results indicate that U. jamaicensis is hypersensitive to TBT exposure. The elasmobranch gill showed a distorted, swollen epithelium with exfoliation following acute exposure to as little as 0.05 microg/L TBTO for 3 h. Graphite furnace atomic absorption spectroscopy (GFAAS) results indicate that tissues of treated animals contained a significantly increased tin concentration as compared to controls. Western blot analysis demonstrated the induction of the stress proteins Hsp 70 and HO1. 4-Hydroxynonenol (4HNE) adduct formation determined by Western blot analysis provides further evidence that observed membrane degradation is a result of lipid peroxidation.     

儿童包皮环切术的术前护理

目的 探讨包皮环切术的术前护理方法.方法 随机抽取在门诊行包皮环切术的患儿100例.在术前一周,实施包皮翻转、包茎扩张、粘连松解,局部清洁积垢等术前护理措施,待炎症、粘连面完全愈合后再行包皮环切术.结果 采取本护理措施的100例患儿,行包皮环切术后,伤口均正常愈合,无1例发生感染,平均愈合时间为5.2天.结论 行包皮环切术前常规实施包皮翻转、包茎扩张、粘连松解,局部清洁积垢等术前护理措施,可以有效地减轻术后伤口的水肿、疼痛以及减少术后伤口的感染和再粘连机会,从而提高手术的成功率.     

Molluscicidal activity of potassium to the zebra mussel, Dreissena polymorphia: toxicity and mode of action

A diverse array of chemicals has been proposed as control agents for the destructive, biofouling bivalve, Dreissena polymorpha, commonly known as the zebra mussel. The zebra mussel has caused great economic hardship in industries situated on Lake Erie due to its proclivity for fouling the inside of water intake pipes and blocking the flow of water. The mussel also has had a significant ecological impact by consuming huge amounts of phytoplankton.

Because the water in which zebra mussels reside may ultimately be consumed by humans and because protection of commercial fish is as important as controlling the zebra mussels, control methods must distinguish between desirable species and the zebra mussels. Most of the currently available molluscicides do not. However, we report that environmentally innocuous derivatives of potassium (e.g. KH₂PO₄ and KCl) can kill zebra mussels at relatively low concentrations without affecting most nontarget organisms. Potassium phosphate is efficacious in killing the zebra mussels across a range of environmental conditions. Potassium chloride or other potassium salts may be used as a substitute when ambient calcium levels in the water result in the formation of a water insoluble precipitate upon combining with dissociated phosphate. Potassium appears to kill the mussels by destroying the integrity of the mussels' gill epithelium, which leads to asphyxiation.     

Isolation and characterisation of some antifouling agents from the brown alga Sargassum confusum

Fats and phthalic acid derivatives were isolated and characterised based on their spectral analysis from the antifouling activity guided fractions of n-hexane and methanol extract of the brown alga Sargassum confusum. The fractions, as well as the isolated compounds, demonstrated significant antifouling activity against spores of a major fouling alga Ulva pertusa with 50-75% decrease of spore attachment on agar-coated slides.     

Investigations into the Fouling Mechanism of Parvovirus Filters During Filtration of Freeze–Thawed mAb Drug Substance Solutions

Filtration to remove viruses is one of the single most expensive steps in the production of mAb drug products. Therefore, virus filtration steps should be fully optimized, and any decline in flow rates warrants investigation into the causes of such membrane fouling. In the current study, it was found that freezing and thawing of a mAb bulk drug solution caused a substantial decrease in viral filter membrane flow rate. Freezing and thawing also caused formation of aggregates and particles across a broad size range, including particles that could be detected by microflow imaging (≥1 μm in size). However, removal of these particles offered little protection against flow rate decline during viral filtration. Further investigation revealed that trace amounts of aggregates (ca. 10⁻⁶ of the total mass of protein in solution) approximately 20–40 nm in size were primarily responsible for the observed membrane fouling.     

重楼乙醇提取液的微滤过程

重楼乙醇提取液可用陶瓷微滤膜处理.考察了不同材料及孔径的膜分离性能,以及操作压力、料液浓度等因素对微滤的影响.并针对污染体系的特性,比较各种膜清洗剂的清洗效果,结果显示0.2μm的ZrO2膜较适合.操作压力、流速和反冲方法均显著影响膜通量.     

Ultrastructure of Mycoplasma pneumoniae exposed to macrolide antibiotics during cultivation on a glass surface and in an organ culture, in relation to their mycoplasma-killing activity

The macrolide antibiotics midecamycin acetate (MOM), erythromycin (EM), midecamycin (MDM), josamycin (JM) and rokitamycin (RKM) showed killing activity against Mycoplasma pneumoniae strain FH-P24. The activity of MOM, EM and JM was not influenced by the number of organisms inoculated, but that of RKM was markedly decreased by a large inoculum. Scanning electron microscopic observations showed many long filaments crossing over each other with small colonies when the organisms were cultivated on a glass surface without any drug for 72 h. When they were exposed to four times the MIC of MOM, the filamentous forms were decreased and the colonies did not grow to a large size. However, after exposure to the other macrolides, the colonies grew larger. Transmission electron micrographs revealed that intracellular vacuolization of the organisms was induced by exposure to MOM, EM and JM, but a mixture of vacuolized cells and "young" organisms was observed after exposure to MDM and RKM. In hamster tracheal organ cultures, the number of organisms was greatly decreased by exposure to four times the MIC of MOM, and the remaining filamentous and colonized organisms were lysed. However, treatment with four times the MIC of the other macrolides induced hardly any lysis of the organisms. In transmission electron micrographs, filamentous and rounded organisms filling the ribosome-like matrix could be seen on the epithelial surface. Treatment with four times the MIC of these macrolides decreased the number of organisms and vacuolized filamentous organisms could be seen on the epithelial cells.     

Oxacillin susceptibility of coagulase-negative staphylococci: role for mecA genotyping and E-test susceptibility testing

Meropenem (MEM) is a carbapenem antibiotic effective against infections caused by a variety of organisms. This study was conducted to evaluate MEM, which has not been previously used in the hospital, in parallel with some antimicrobial agents now in use, against organisms causing serious infections in the hospital. A total of 382 organisms isolated from blood cultures were included in the study. In the case of Bacteroides spp. and Burkholderia pseudomallei, organisms recovered from blood as well as from other sites were also included. In addition to MEM, 12 antimicrobial agents were tested against Gram-negative bacilli and seven against staphylococci. Antimicrobial susceptibility testing was carried out by the Kirby-Bauer disc diffusion technique based on the M2-A4 standard. The present paper demonstrates that meropenem, imipenem and ciprofloxacin are the most active antimicrobial agents against clinically important organisms causing serious infections in the hospital.     

司帕沙星与其他5种抗菌药体外抗菌活性比较研究

测定了司帕沙星对临床分离的１９９ 株致病菌的体外抗菌活性并与氧氟沙星、环丙沙星、头孢唑啉、头孢噻肟、阿米卡星的抗菌活性进行比较。司帕沙星对革兰阳性菌的ＭＩＣ９０为０．１２５～０．５ｍ ｇ／Ｌ,对金葡球菌、化脓链球菌的抑菌率均为１００％ ,强于氧氟沙星、环丙沙星;对革兰阴性菌也具有良好的体外抗菌活性,与氧氟沙星、环丙沙星相似。不同细菌接种量和不同浓度血清对其抗菌活性无明显影响,仅在ｐＨ５．０ 时抗菌活性略有下降