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1.
几种淡水蚌外套膜蛋白质氨基酸组成及部分元素分析   总被引:4,自引:0,他引:4  
测定了三角帆蚌、圆背角无齿蚌、褶纹冠蚌、背视丽蚌外套膜的粗蛋白含量 ,分析了外套膜干粉的氨基酸组成 ,并采用原子吸收光谱法和等离子吸收光谱法测定三角帆蚌、圆背角无齿蚌、褶纹冠蚌外套膜的 12种元素含量。结果表明 :干燥外套膜蛋白质含量为 :三角帆蚌 4 1 34% ,圆背角无齿蚌2 2 0 3% ,褶纹冠蚌 32 14 % ,背视丽蚌 7 78%。这四种淡水蚌外套膜均含有 17种氨基酸。被测的 12种元素中 ,Cu元素含量最高 ,其次是Fe ,Mn ,Mg ,Ca ,Zn ,Cr,而Ni,Co ,Pb ,Hg等元素含量较低。这四种淡水蚌外套膜是一类优质的动物蛋白质资源。  相似文献   

2.
河蚌培养组织的几种生化成分分析   总被引:1,自引:0,他引:1  
本文分析测定了三角帆蚌,褶纹冠蚌和背角无齿蚌外套膜培养组织及其培养液中的氨基酸,牛磺酸及钙含量。在珍蛛中含量较高的丙的氨酸和甘氨酸分别增加541%和91%。三种蚌在培养中牛磺酸含量增加5.78%到3倍,培养组织的钙含量增加1倍左右。同时测定了培养组织的碱性磷酸酶活性,培养组织与河蚌外套膜具有相近的比活及相对酶活。结果表明,河蚌外套膜在离体培养条件下,也具有分泌珍珠质的能力。  相似文献   

3.
SCGE技术检测镉对背角无齿蚌血细胞DNA的损伤   总被引:2,自引:0,他引:2  
以背角无齿蚌(Anodonta woodiana woodiana)为研究对象,利用单细胞凝胶电泳技术检测不同浓度及不同染毒时间氯化镉对背角无齿蚌血细胞DNA的损伤作用。结果显示,染毒后的背角无齿蚌血细胞均出现了拖尾现象,各染毒组与对照组相比,拖尾增长明显。剂量效应组中,蚌暴露在不同浓度(0、1、10、50mg·L-1)的氯化镉中72 h,各组蚌血细胞DNA平均迁移长度及彗尾DNA含量均明显增加,与阴性对照组比较差异显著(p<0.01),存在显著的剂量-效应关系;在时间效应组中,蚌暴露在10mg·L-1的氯化镉中分别24、48、72、96 h,随着氯化镉染毒时间的延长,各染毒组细胞DNA平均迁移长度及彗尾DNA含量与0时间组比较差异显著(p<0.01),但时间-效应关系不明显。  相似文献   

4.
河蚌的晶杆   总被引:3,自引:0,他引:3  
背角无齿蚌(Anodonta woodiana)一般称河蚌或菜蚌.生活在湖泊、池塘、河流、沟渠的水底淤泥内.在我国分布很广泛,是一种习见的淡水蚌类. 背角无齿蚌的消化道内有一晶杆(crystallioe style)构造.有人认为在幽门盲囊(晶杆  相似文献   

5.
滤食性贝类与沉水植物是水生态系统的重要组成部分,对浅水湖泊生态系统的结构、功能和过程具有重要影响,但两者共存产生的生态环境效应尚不明确。本文以背角无齿蚌(Anodonta woodiana)及沉水植物苦草(Vallisneria natans)为对象,通过构建中型水生态系统(对照组、蚌处理组、草处理组、蚌草共存组),研究了背角无齿蚌、苦草及其共存对水质的影响。结果表明:背角无齿蚌可显著降低浮游藻类生物量(Chl-a,P0.05);苦草显著降低了总氮(TN)、硝态氮(NO3--N)、总磷(TP)、溶解性总磷(TDP)及浮游藻类Chl-a(P0.05);蚌草共存显著降低了氮、磷营养盐水平及浮游藻类Chl-a(P0.05);背角无齿蚌对苦草的生长起促进作用,实验结束时蚌草共存组的苦草干重及株高显著高于草处理组(P0.05)。  相似文献   

6.
温度、pH对二种淡水贝类滤水率的影响   总被引:10,自引:1,他引:9  
实验在3m×5m×05m的控温池中进行,以小球藻作投喂饵料,利用直径40cm、高度50cm的陶瓷桶测定了不同规格下5个温度梯度(15、20、25、30、35℃)和5个pH梯度(5、6、7、8、9)背角无齿蚌和三角帆蚌的滤水率,其结果显示①5g左右的三角帆蚌在pH值为7时滤水率最大(0935mlg·min);②平均湿重为(2974±225)g,(611±71)g,(232±54)g的背角无齿蚌的滤水率在20~30℃间较高,以30℃最大,达10884mlg·min。随着规格的增大,背角无齿蚌的滤水率逐渐减少,这种趋势在20、25℃时表现得更为明显。③平均湿重为(3943±307)g,(1055±142)g,(302±58)g的三角帆蚌在水温20、25和30℃时的滤水率均远远大于其它2个温度梯度,中规格蚌的滤水率在30℃最大,大规格和小规格蚌的滤水率均在25℃时最大。  相似文献   

7.
2009年5月31日-6月20日在广东省大沙河水库利用微型生态系统比较不同放养密度的褶纹冠蚌(Cristaria plicata)和背角无齿蚌(Anodonta woodiana)对水体氮、磷及浮游植物的影响,探讨两种蚌在控制南亚热带水库富营养化水体藻类水华上的可行性。实验结果表明,在褶纹冠蚌和背角无齿蚌处理组中,总氮、总磷和叶绿素a浓度显著增加,而铵氮的浓度显著下降;褶纹冠蚌和背角无齿蚌导致了浮游植物群落组成结构的改变和数量的增加,实验过程中绿藻所占的比例迅速上升。两种蚌之间没有显著的差异,只是在不同的作用强度下,时间上的响应不同。综合实验结果,褶纹冠蚌和背角无齿蚌难以有效地运用于我国华南地区水库的水质改善与富营养化控制。  相似文献   

8.
张帅  陈修康  肖利娟  胡韧 《生态科学》2011,30(3):280-287
2009年5月31日-6月20日在广东省大沙河水库利用微型生态系统比较不同放养密度的褶纹冠蚌(Cristaria plicata)和背角无齿蚌(Anodonta woodiana)对水体氮、磷及浮游植物的影响,探讨两种蚌在控制南亚热带水库富营养化水体藻类水华上的可行性。实验结果表明,在褶纹冠蚌和背角无齿蚌处理组中,总氮、总磷和叶绿素a浓度显著增加,而铵氮的浓度显著下降;褶纹冠蚌和背角无齿蚌导致了浮游植物群落组成结构的改变和数量的增加,实验过程中绿藻所占的比例迅速上升。两种蚌之间没有显著的差异,只是在不同的作用强度下,时间上的响应不同。综合实验结果,褶纹冠蚌和背角无齿蚌难以有效地运用于我国华南地区水库的水质改善与富营养化控制。  相似文献   

9.
背角无齿蚌外套膜的组织化学研究   总被引:5,自引:0,他引:5  
背角无齿蚌(Anodonta woodiana elliptica)在我国分布很广,是我国三种淡水育珠蚌之一。它所形成的珍珠微带金黄色,具有特殊的风格。四川省安岳县自1971年开始使用背角无齿蚌进行珍珠养殖以来,获得了不少经济利益,并积累了一些育珠经验。为了进一步探讨珍珠形成机理,以利于提高珍珠质量,从而获得更多优质珍珠。我们在对我国淡水育珠河蚌外套膜组织学和染色体等研究的基础上,又采用组织化学方法,对背角无齿蚌外套膜细胞中的核酸、糖类、酶等生物大分子物质作了组织化学方面的一些观察研究。  相似文献   

10.
本研究以背角无齿蚌为材料,利用嗜水气单胞菌为诱导刺激物,对背角无齿蚌进行注射感染,在注射后3、6、12 、24、48h分别取血淋巴、肝胰腺,测定其超氧化物歧化酶(SOD)、酚氧化酶 (PO)、酸性磷酸酶 (ACP)、碱性磷酸酶 (AKP) 及过氧化氢酶 (CAT) 的活力,并研究各项酶活力的变化规律。结果表明:除3h肝胰腺外,实验组的SOD活力均不同程度地高于对照组;血清实验组的PO活力开始显著高于对照组,然后降低,而肝胰腺实验组的PO活力持续高于对照组;另外,与对照组相比,实验组中血淋巴与肝胰腺的ACP、AKP和CAT活力在不同的时间段虽然有所增强,但两者之间无显著差异。因此,认为SOD、PO活性可以作为背角无齿蚌免疫抗病功能指标参数,而ACP、AKP及CAT活性能否作为该参数还有待于进一步研究。  相似文献   

11.
Deuterostome invertebrates possess complement genes, and in limited instances complement-mediated functions have been reported in these organisms. However, the organization of the complement pathway(s), as well as the functions exerted by the cloned gene products, are largely unknown. To address the issue of the presence of an inflammatory pathway in ascidians, we expressed in Escherichia coli the fragment of Ciona intestinalis C3-1 corresponding to mammalian complement C3a (rCiC3-1a) and assessed its chemotactic activity on C. intestinalis hemocytes. We found that the migration of C. intestinalis hemocytes toward rCiC3-1a was dose dependent, peaking at 500 nM, and was specific for CiC3-1a, being inhibited by an anti-rCiC3-1a-specific Ab. As is true for mammalian C3a, the chemotactic activity of C. intestinalis C3-1a was localized to the C terminus, because a peptide representing the 18 C-terminal amino acids (CiC3-1a(59-76)) also promoted hemocyte chemotaxis. Furthermore, the CiC3-1a terminal Arg was not crucial for chemotactic activity, because the desArg peptide (CiC3-1a(59-75)) retained most of the directional hemocyte migration activity. The CiC3-1a-mediated chemotaxis was inhibited by pretreatment of cells with pertussis toxin, suggesting that the receptor molecule mediating the chemotactic effect is G(i) protein coupled. Immunohistochemical analysis with anti-rCiC3-1a-specific Ab and in situ hybridization experiments with a riboprobe corresponding to the 3'-terminal sequence of CiC3-1, performed on tunic sections of LPS-injected animals, showed that a majority of the infiltrating labeled hemocytes were granular amebocytes and compartment cells. Our findings indicate that CiC3-1a mediates chemotaxis of C. intestinalis hemocytes, thus suggesting an important role for this molecule in inflammatory processes.  相似文献   

12.
摘要 目的:探讨直肠癌患者术后血清C反应蛋白、白蛋白、单核细胞趋化蛋白的表达及对吻合口瘘的预测价值。方法:选择2017年4月至2019年4月于我院进行直肠癌手术患者102例患者进行研究,其中42例发生术后吻合口瘘,设为试验组,剩余60例未发生吻合口瘘作为对照组。分析患者术后血清C反应蛋白、白蛋白、单核细胞趋化蛋白水平变化情况,采用受试者工作特征曲线分析血清C反应蛋白、白蛋白、单核细胞趋化蛋白对术后发生吻合口瘘的预测价值。结果:试验组术后血清C反应蛋白、单核细胞趋化蛋白水平显著高于对照组,白蛋白水平显著低于对照组,差异显著(P<0.05);行预防性造口组术后血清C反应蛋白、单核细胞趋化蛋白水平显著低于未预防性造口组,白蛋白水平显著高于未预防性造口组,差异显著(P<0.05);血清C反应蛋白预测术后吻合口瘘的临界值为39.69 mg/L,灵敏度为71.47%,特异度为83.14%,AUC为0. 824,血清白蛋白预测术后吻合口瘘的临界值为29.76 g/L,灵敏度为61.20%,特异度为79.40%,AUC为0. 746,血清单核细胞趋化蛋白预测术后吻合口瘘的临界值为200.09 pg/mL,灵敏度为61.18%,特异度为80.45%,AUC为0. 605,联合检测较单独检测具有更高的灵敏度和特异度,分别为77.56%、86.38%。结论:术后血清C反应蛋白、白蛋白、单核细胞趋化蛋白水平对直肠癌患者术后吻合口瘘具有较好的预测价值。  相似文献   

13.
Immunocompetence of bay mussels, Mytilus edulis, with hemic neoplasia was investigated with an in vitro yeast phagocytosis assay and by in vivo clearance from the blood of injected Cytophaga sp. bacteria. The yeast phagocytosis assay was conducted with hemocytes maintained in 90% plasma. Neoplastic hemocytes, characterized by enlarged nuclei and scant cytoplasm, failed to phagocytose yeast cells. In contrast, greater than 90% of hemocytes from unaffected animals and morphologically normal hemocytes from mussels with the disease phagocytosed yeast. Substitution of normal plasma with that from a mussel with advanced disease (essentially 100% neoplastic hemocytes) did not affect the phagocytic capability of normal hemocytes. Conversely, normal plasma did not enhance the phagocytic capabilities of neoplastic cells. Mussels with advanced disease showed reduced bacterial clearance; control or lightly affected mussels (less than 11% neoplastic hemocytes) cleared greater than 90% of injected bacteria in 4 hr, while mussels with advanced disease cleared 44-83%. These experiments indicate that mussels with advanced hemic neoplasia have compromised defense systems. This may account for the reported mortality in mussels and other bivalve molluscs with hemic neoplasia.  相似文献   

14.
Effect of biogenic amines and cannabinoids on bacterial chemotaxis   总被引:2,自引:2,他引:0       下载免费PDF全文
The chemotactic response of Pseudomonas fluorescens was significantly enhanced by the stimulants dl-amphetamine and epinephrine. Acetylcholine, a physiological antagonist of epinephrine, and the cannabinoid tetrahydrocannabinol inhibited bacterial chemotaxis. It may be possible to use bacterial chemotaxis as a bioassay in biochemical studies of drug action.  相似文献   

15.
Previous investigations have demonstrated that the chemotactic response of polymorphonuclear leukocytes (PMN) was stimulated by hyaluronic acid (HA) when serum was present. The aim of the present investigation was to identify the serum factor necessary for the stimulation of PMN chemotaxis by HA. By means of gel filtration, the m.w. of the serum component was shown to be greater than 350,000. Immunoprecipitation of serum with anti-fibronectin, but not with anti-IgM and anti-alpha 2-macroglobulin, inhibited the stimulation of PMN chemotaxis by HA. Preincubation of PMN with HA (10 to 500 micrograms/L) and isolated fibronectin (0.1 to 100 mg/L) significantly stimulated the chemotactic response of PMN. Also, random migration of PMN was significantly increased by preincubation of the cells with HA (10 to 500 micrograms/L) and isolated fibronectin (50 to 200 mg/L). Additionally, PMN preincubated with HA (10 to 50 micrograms/L) and with fibronectin (10 to 50 mg/L) added afterwards, and PMN preincubated with fibronectin (10 mg/L) and with HA (5 to 10 micrograms/L) added after the preincubation, showed a significant stimulation of the chemotactic response. PMN preincubated with serum and chondroitin sulfate, or with fibrinogen and HA, demonstrated no stimulation of the chemotactic response. The present investigation suggests that the combined action of HA and fibronectin, which probably takes place at the cellular membrane, is a major mechanism in the HA-mediated stimulation of PMN migration.  相似文献   

16.
Pseudomonas fluorescens WCS365 is an excellent competitive colonizer of tomato root tips after bacterization of seed or seedlings. The strain controls tomato foot and root rot (TFRR) caused by the phytopathogenic fungus Fusarium oxysporum f. sp. radicis-lycopersici. Under biocontrol conditions, fungal hyphae were shown to be colonized by WCS365 bacteria. Because chemotaxis is required for root colonization by WCS365 cells, we studied whether chemotaxis also is required for hyphae colonization. To that end, an in vitro assay was developed to study hyphae colonization by bacteria. The results indicated that cells of the cheA mutant FAJ2060 colonize hyphae less efficiently than cells of wild-type strain WCS365, when single strains were analyzed as well as when both strains were applied together. Cells of WCS365 show a chemotactic response toward the spent growth medium of F. oxysporum f. sp. radicis-lycopersici, but those of its cheA mutant, FAJ2060, did not. Fusaric acid, a secondary metabolite secreted by Fusarium strains, appeared to be an excellent chemo-attractant. Supernatant fluids of a number of Fusarium strains secreting different levels of fusaric acid were tested as chemo-attractants. A positive correlation was found between chemo-attractant activity and fusaric acid level. No chemotactic response was observed toward the low fusaric acid-producer FO242. Nevertheless, the hyphae of FO242 still were colonized by WCS365, suggesting that other metabolites also play a role in this process. The possible function of hyphae colonization for the bacterium is discussed.  相似文献   

17.
血管活性肠肽对支气管上皮细胞趋化迁移的影响及机制   总被引:2,自引:0,他引:2  
Guan CX  Zhang CQ  Qin XQ  Luo ZQ  Zhou FW  Sun XH 《生理学报》2002,54(2):103-106
为探讨肺内神经肽在气道损伤修复中的作用 ,采用blind wellBoydenchamber测定原代培养的支气管上皮细胞 (bronchialepithelialcells,BEC)趋化性 ,观察血管活性肠肽 (vasoactiveintestinalpeptide ,VIP)对BEC趋化迁移的影响及其机制 ,并测定经热应激后BEC分泌VIP及表达VIP受体 (vasoactiveintestinalpeptidereceptor,VIPR)的变化。结果显示 :(1)以胰岛素作为趋化因子所建立的BEC趋化性测定方法稳定 ,重现性好 (r =0 970 3,P <0 0 1) ;(2 )VIP (0 0 0 1~ 1μmol/L)均显示剂量依赖性地增强BEC的趋化迁移 ,其效应可被钙调蛋白阻断剂及蛋白激酶C阻断剂有效地抑制 (P <0 0 1) ;(3) 4 2℃、30min热应激后BEC分泌VIP (P <0 0 1)及表达VIPR明显增加 (P <0 0 5 )。实验表明 :肺内神经肽VIP可增强BEC的趋化迁移 ,其细胞内信号转导途径与钙调蛋白及蛋白激酶C有关。而热应激时VIP及VIPR的高表达进一步提示局部微环境的VIP可能是气道上皮损伤修复网络中的重要分子  相似文献   

18.
Swimming bacteria sense and respond to chemical signals in their environment. Chemotaxis is the directed migration of a bacterial population toward increasing concentrations of a chemical that they perceive to be beneficial to their survival. Bacteria that are indigenous to groundwater environments exhibit chemotaxis toward chemical contaminants such as hydrocarbons, which they are also able to degrade. This phenomenon may facilitate bioremediation processes by bringing bacteria into closer proximity to these contaminants. A microfluidic device was assembled to study chemotaxis transverse to advective flow. Using a T-shaped channel design (T-sensor), two fluid streams were brought into contact by impinging flow. They then flowed adjacent to each other along a transparent channel. An advantage to this design is that it allows real-time visualization of bacterial distributions within the channel. Under laminar flow conditions a chemotactic driving force was created perpendicular to the direction of flow by diffusion of the chemical attractant from one input stream to the other. A comparison of the chemotactic band behavior in the absence and presence of flow showed that fluid velocity did not significantly impede chemotactic migration in the transverse direction.  相似文献   

19.
Neutrophils are the predominant cells accumulated in the synovial fluid (SF) of rheumatoid arthritis (RA) patients. Accumulation of neutrophils may be regarded as a possible way by which neutrophils exert cytotoxic functions. The aim of the present study was to analyze the chemotactic response of neutrophils (PMNs) isolated from the peripheral blood or SF of patients with RA by performing the chemotaxis assay, in which N-formyl-methionyl-leucyl-phenylalanine (FMLP) was used as chemotactic agent. Our results showed that FMLP induced response of peripheral blood neutrophils from 12 patients with RA was similar with the response of 15 healthy controls. A decreased chemotactic response to FMLP was, however, observed in PMNs isolated from the SF of RA patients as comlipared with peripheral blood cells. Therefore, this defective chemotactic ability of neutrophil, was inversely correlated with the number of infiltrating cells in SF. These results indicate that chemotactic ability of neutrophils may be reduced after migration to the SF. Because PMNs chemotaxis in vivo has likely occurred in the presence of serum or SF, we tried to simulate the same conditions in vitro. Therefore, we analyzed the effect of serum or SF on the RA-PMNs chemotaxis. Heat-inactivated serum produced a marked reduction of chemotactic activity developed by PMNs isolated from patients with RA. Notably, a significant increase of chemotactic activity was observed when FMLP and serum stimuli were used together, as compared with the same stimuli used alone. The results suggested that complement activation might interfere with neutrophils chemotaxis. SF amplifies the chemotactic activity of PMNs isolated from peripheral blood of RA patients, but does not affect the chemotaxis developed by PMNs isolated from SF. The data might suggest that several components of SF (IL-8, leukotrien B4, thrombin, platelet-activating factor, etc.) could serve as a potent stimulus for recruitment of neutrophils from periphery into the RA joint. In conclusion, serum or SF components seem to contribute to chemotaxis of neutrophils and play a role in differential killing of PMNs and incidence of infection.  相似文献   

20.
It has been demonstrated that hemocytes collected from the American oyster, Crassostrea virginica, 2 hr postchallenge with live Bacillus megaterium are significantly less chemotactic to this bacterium. Since chemotaxis between hemocytes and non-self materials is an integral part of the cellular internal defense mechanism in mollusks, this finding may be important in our understanding of reduced cellular reactions in prechallenged animals.  相似文献   

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