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21.
There may exist a connection between Echinococcus granulosus infection and cancer development. Here, it is aimed to investigate specific effects of E. granulosus protoscoleces (PSCs) on the proliferation and invasion capacities of hepatocellular carcinoma (HCC) cells in vitro and ex vitro. HepG2 cells were cultured with different quantities of E. granulosus PSCs in vitro. MTT analysis was used to evaluate effects of E. granulosus PSCs on the proliferation of HepG2 cells. Besides, scratch and transwell assays were respectively used for the detection of HepG2 cells migration and invasion capacities after co-culture with E. granulosus PSCs. Then, HepG2 cells were subcutaneously transplanted into nude mice with or without E. granulosus PSCs. From the 25th day of transplantation, the volume of subcutaneous lesions was measured every four days. At the 37th day, subcutaneous lesions were removed and their weight was evaluated. H&E staining was used for detecting basic pathological changes. HepG2 cells grew well without obvious morphological changes. Proliferation rate and migration capacity of HepG2 cells were higher in the co-culture group than the control group, which was closely associated with quantities of E. granulosus PSCs and co-culture time length. Moreover, HepG2 cells co-cultured with E. granulosus PSCs had stronger invasion ability than the control HepG2 cells. Importantly, there existed significant differences in the volume and weight of subcutaneous lesions after transplanting HepG2 cells with E. granulosus PSCs than the control group. HepG2 cells were also more pathologically heterogeneous in morphology after transplantation with E. granulosus PSCs. Thus, E. granulosus PSCs may promote proliferation and invasion of HCC cells.  相似文献   
22.
Quazithelazia rostrata n. sp. from Ceyx erithaca (L.) (type-host) and Alcedo euryzona Temminck (Coraciiformes, Alcedinidae) and Q. alata n. sp. from Enicurus ruficapillus Temminck (Passeriformes, Muscicapidae) are described from vicinities of Gombak Biological Station, Selangor, Malaysia; both species are parasitic under the koilin lining of the gizzard. Paratypes of Schistogendra pelargopsis Nandi, De & Majumdar, 1985, a parasite of Pelargopsis capensis (L.) (Alcedinidae) from India, are redescribed and the species is recognised as a junior synonym of the type-species of Quasithelazia, Q. tenuis Maplestone, 1932 (new synonymy), a species originally described from Halcyon smyrnensis (L.) (Alcedinidae) in India. An amended diagnosis of the genus Quasithelazia Maplestone, 1932 is proposed. Currently, this genus includes eight species occurring in the Old World, six of them parasitic in kingfishers (Alcedinidae) and two species parasitic in flycatchers (Muscicapidae). These include, inter alia, Q. halcyoni n. comb. for Viktorocara halcyoni Ryzhikov & Khokhlova, 1964 from Halcyon smyrnensis and H. pileata (Boddaert) in Vietnam and the Russian Far East, Q. microcordonis n. comb. for Rusguniella microcordonis Schmidt & Kuntz, 1971 from Halcyon coromanda major (Temminck & Schlegel) in Taiwan and Q. multipapillata n. comb. for Schistogendra multipapillata Zhang, 1993 from Tarsiger cyanurus (Pallas) (Muscicapidae) in China. Comparative morphological data for Quasithelazia spp. are presented. Schistogendra oligopapillata Zhang & An, 2002 from domestic ducks in China is considered a species incertae sedis.  相似文献   
23.
Parachordatortilis n. g. is proposed as a monotypic genus for Parachordatortilis mathevossianae (Petrov & Chertkova, 1950) n. comb. (Spirurida, Acuariidae), previously Dispharynx mathevossianae Petrov & Chertkova, 1950. The new genus can be distinguished from all other acuariid genera by having cordons with a sinistral torsion. Parachordatortilis possesses cordons consisting of two rows of delicate cuticular plates delimiting a longitudinal canal. This pattern of cordon structure suggests that Parachordatortilis is closely related to Dispharynx Railliet, Henry & Sisoff, 1912, Synhimantus Railliet, Henry & Sisoff, 1912 and Chordatortilis Machado de Mendon?a & Olivera de Rodrigues, 1985. P. mathevossianae is redescribed on the basis of light and scanning electron microscopical observations of specimens collected from a common kestrel Falco tinnunculus L. in southern Italy.  相似文献   
24.
Syncuaria mackoi n. sp. is described, based on light and scanning electron microscopy, from the stomach of the black stork Ciconia nigra in Bulgaria. The new species is characterised by: body length 7.18–8.30 mm (males) and 10.13–11.40 mm (females); cordons anastomosing about the level of the middle of the muscular oesophagus and consisting of delicate cuticular plates; bifurcate deirids 7–9 μm long; lateral longitudinal cuticular band-like swellings; nine pairs of pedunculate caudal papillae, i.e. four precloacal and five postcloacal, the latter forming two groups (2 + 3); sixth pair of postcloacal papillae sessile; left spicule 854–907 μm long; right spicule 138–154 μm in length, with a curved distal end resembling a horn and a short lateral projection at some distance from its tip; and vagina vera provided with an anteriorly-directed blind appendix. The specimens identified as S. ciconiae (Gil’bert, 1927) by Macko (1964) from C. nigra in Slovakia are considered as belonging to S. mackoi. A pair of small cupolae situated dorsally and ventrally between bases of cordons of the new species is described for the first time in this genus; they are recognised as homologous to the pair of spines in the same position previously described in S. diacantha Petter, 1961 and S. plegadisi Digiani, 1999.  相似文献   
25.
龙须菜对富营养化海水的生物修复   总被引:16,自引:3,他引:13  
于2002年至2004年期间,在福建省东山岛的八尺门鱼类网箱养殖区、西埔湾对虾养殖区、乌礁湾鲍鱼养殖区等进行了龙须菜(G racilaria lem aneaf orm is)对动物海水养殖造成的富营养化的生物修复研究。结果表明,从围隔实验到小面积的海区实验到大面积的海区推广试点,龙须菜对富营养化的海水均有良好的修复效果。围隔实验中,龙须菜能使网箱养殖区缺氧的海水达到过饱和状态,对无机氮(IN)、无机磷(IP)的去除率达80%以上;实验海区,修复区的溶解氧(DO)浓度明显高于非修复区,IN、IP、叶绿素(Ch l-a)浓度低于非修复区;推广海区,鲍鱼养殖污水流经龙须菜养殖区后,IN、IP得到有效的吸收,DO浓度得到提高。因此,大面积养殖龙须菜对减轻养殖污水对海区的污染,防止水体富营养化,抑制赤潮的发生有积极作用。  相似文献   
26.
本文采用饵剂饲喂方法研究东亚飞蝗Locusta migratoria manilensis(Meyen)营养生理参数变化,结果表明:绿僵菌(Metarhizium anisopliae)侵染后,5个温度梯度下蝻期总取食量分别为96.4、108.3、131.9、103.2、249.5mg;21、24、27、30℃4个温度...  相似文献   
27.
【目的】基于当前细胞表面展示体系存在的问题,旨在构建一个新型的普适性强、抗逆性好、高效稳定的酿酒酵母孢子表面展示系统。【方法】首先,根据酵母孢子固定化酶的特性,通过查阅文献寻找潜在的与孢子壁壳聚糖层高度亲和的壳聚糖结合模块;其次,利用绿色荧光蛋白(green fluorescent protein,GFP)与结合模块融合表达,在体外和孢子内分别验证结合模块与孢子壁的亲和能力;之后,选择Saccharomyces cerevisiae AH109来源的α-半乳糖苷酶(α-galactosidase,MEL1)评估新型展示体系的效能。【结果】首先,选择Paenibacillussp. IK-5来源壳聚糖酶的碳水化合物结合模块32 (carbohydrate binding module 32,CBM32)作为壳聚糖结合模块。其次,将大肠杆菌表达纯化后的融合蛋白CBM32-GFP与dit1Δ孢子共孵育,通过GFP荧光定位以及荧光强度验证CBM32在体外与孢子壁具有较好的亲和能力;CBM32-GFP在dit1Δ孢子内的荧光定位与结合能力证明了其在孢子内能够与孢子壁紧密结合;最后,以MEL1替换GFP应用到新型展示体系中,与只表达MEL1的孢子相比,CBM32-MEL1孢子酶活不仅提高了68.65%,最高酶比活力达到460.59 U/g DCW (dry cell weight, 菌体干重),重复使用能力也得到了显著提高;此外,该体系提高了MEL1的稳定性和可操作性。【结论】本研究首次提出利用结合模块来构建一个新型酿酒酵母孢子表面展示体系,为真核来源的多糖基化位点修饰以及多亚基结构蛋白提供了可靠的细胞表面展示平台,为实现工业化应用孢子固定化酶提供了理论依据。  相似文献   
28.
Decorataria magnilabiata (Molin, 1860) n. comb. is proposed for Dispharagus magnilabiatus Molin, 1860 [= Acuaria (Cheilospirura) magnilabiata (Molin, 1860) Railliet, Henry & Sisoff, 1912; Cheilospirura magnilabiata (Molin, 1860) Stiles & Hassall, 1920; Dispharynx magnilabiata (Molin, 1860) Gendre, 1920] (Nematoda, Spirurida, Acuariidae), a parasite of the roseate spoonbill Platalea ajaja L. (Ciconiiformes, Threskiornithidae) known from Brazil, France (bird in captivity), Argentina and Cuba. The species is redescribed and illustrated on the basis of the type-series (from Brazil) in the Helminthological Collection of the Naturhistorisches Museum, Vienna. Syncuaria diacantha Petter, 1961 [= Decorataria diacantha (P.) Skryabin, Sobolev & Ivashkin, 1965], originally described from Platalea ajaja in France (bird in captivity), is recognised as a junior synonym of Decorataria magnilabiata (new synonymy).  相似文献   
29.

Background

Among the arthropod-borne nematodes infesting dogs, Onchocerca lupi (Spirurida: Onchocercidae) is of increasing zoonotic concern, with new human cases of infection diagnosed in Turkey, Tunisia, Iran and the USA. Knowledge of the biology of this nematode is meagre. This study aimed at assessing the distribution and periodicity of O. lupi microfilariae from different body regions in naturally infested dogs.

Methodology/Principal Findings

Skin samples were collected from six dogs infested with O. lupi but without apparent clinical signs. Two skin samples were collected from 18 anatomical regions of dog 1 at necropsy. In addition, single skin biopsies were performed from the forehead, inter-scapular and lumbar regions of dogs 2–6, in the morning, afternoon, and at night. Two aliquots of the sediment of each sample were microscopically observed, microfilariae counted and morphologically and molecularly identified. Most of the 1,667 microfilariae retrieved from dog 1 were in the right ear (59.6%), nose (26.5%), left ear (6.7%), forehead (3.0%), and inter-scapular (2.9%) regions. In dogs 2–6, the overall mean number of microfilariae was larger on the head (n = 122.8), followed by the inter-scapular (n = 119.0) and lumbar (n = 12.8) regions. The overall mean number of microfilariae was larger in the afternoon (153.4), followed by night (75.4) and morning (25.8).

Conclusions

Onchocerca lupi microfilariae were more common in the head (i.e., ears and nose) than in the remaining part of the dog''s body, indicating they tend to aggregate in specific body regions, which are the best sites to collect skin samples for diagnostic purposes. The periodicity pattern of microfilariae of O. lupi and their concentration in specific body regions is most likely a result of the co-evolution with their as-yet-unknown vector. The detection of skin microfilariae in asymptomatic animals, suggests the potential role of these animals as carriers and reservoirs of O. lupi.  相似文献   
30.
为阐明西藏飞蝗Locusta migratoria tibetensis Chen散居型地理种群数量性状的地理变异,将散居型西藏飞蝗9个地理种群雌、雄个体的前翅长度(E)、后足股节长度(F)、头宽(C)、前翅长度与后足股节长度比值(E/F)、后足股节长度与头宽比值(F/C)5项形态特征参数进行系统聚类分析和主成分分析....  相似文献   
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