Experimental transmission of Caryospora kutzeri (Apicomplexa: Eimeriidae) by rodent hosts     

Volf J  Modrý D  Koudela B 《Folia parasitologica》2001,48(1):11-14

Four laboratory-hatched European kestrels Falco tinnunculus L. were fed on laboratory mice and common voles Microtus arvalis Pallas previously inoculated with different doses of sporulated oocysts of Caryospora kutzeri B?er, 1982. Two kestrels that were fed infected mice shed C. kurtzeri oocysts 6 days after ingesting murine tissues. To compare direct and indirect transmissions, two of the kestrels were subsequently directly inoculated with 10(5) sporulated C. kutzeri oocysts and became patent on days 8 and 9 and shed caryosporan oocysts up to day 25 post inoculation. Additionally, four mice were inoculated with 10(6) oocysts in order to examine mouse tissues for the presence of developmental stages of C. kutzeri. No coccidian stages were found in the tissues of inoculated mice. The experiment showed that developmental stages of C. kutzeri are able to survive in mouse tissues and cause infection of suitable host after their ingestion.  相似文献   

Antigenic characterization of rat louse Polyplax spinulosa     

P Volf  L Grubhoffer  V Matha 《Folia parasitologica》1990,37(3):275-278

Number and relative molecular weights of proteins in whole body homogenates of the louse, Polyplax spinulosa were determined using SDS-PAGE. 13 protein components from the total of 28 bands were defined as Con A binding glycoproteins. In immunoblotting sera of lice infested laboratory rats of BN strain specifically recognized 3 major protein components with r.m.w. of 77,000, 105,000 and 230,000 Da and from 6 to 8 minor protein components with r.m.w. of 31,000-180,000 Da.  相似文献   

Influence of noncellulosic contents on nano scale refinement of waste jute fibers for reinforcement in polylactic acid films     

Vijay Baheti  Rajesh Mishra  Jiri Militky  B. K. Behera 《Fibers and Polymers》2014,15(7):1500-1506

In the present study, nanofibrils of cellulose are extracted from waste jute fibers using high energy planetary ball milling process in wet condition. The rate of refinement of untreated fibers having non-cellulosic contents was found slower than treated fibers due to strong holding of fiber bundles by non-cellulosic contents. At the end of three hours of wet milling, untreated fibers were refined to the size of 850 nm and treated fibers were refined to the size of 443 nm. In the subsequent stage, composite films of poly lactic acid (PLA) were prepared by solvent casting with 3 wt% loading of untreated jute nanofibrils, treated jute nanofibrils and microcrystalline cellulose. The influence of non-cellulosic contents on mechanical properties of PLA films are investigated based on results of tensile test, dynamic mechanical analysis and differential scanning calorimetry. The maximum improvement was observed in case of treated jute nanofibril/PLA composite film where initial modulus and tensile strength increased by 207.69 % and 168.67 %, respectively as compared to neat PLA film. These improvements are attributed to the increased interaction of treated jute nanofibrils with PLA matrix due to their higher precentage of cellulosic contents and mechanically activated surface.  相似文献   

Isolation and characterization of an immunogen from the louse Polyplax spinulosa     

P Volf  L Grubhoffer 《Veterinary parasitology》1991,38(2-3):225-234

The reaction of Polyplax spinulosa protein components with antigen-specific rat antisera and with five plant lectins is described. In immunoblotting, the antisera from rats infested with the louse P. spinulosa specifically recognized from 7 to 11 antigenic components of louse whole-body homogenates. Affinoblotting analysis with lectins showed that 10 of these components were glycoproteins with different types of glycan structure. Only one immunogenic antigen was isolated using immunoaffinity chromatography with the gammaglobulin fraction of an antigen-specific antiserum as immunospecific ligand. Further electrophoretic and immunochemical analyses revealed that it was a glycoprotein with relative molecular weight (RMW) 31 kDa and with high mannose type of oligosaccharide.  相似文献   

阿拉善双峰驼驼乳蛋白中氨基酸的含量及营养价值     

赵电波  白艳红  吉日木图  张和平 《农产品加工．学刊》2006,(12):26-27,44

对10峰阿拉善双峰驼第一次分娩后、泌乳时间90d时驼乳中的必需氨基酸含量及其营养价值进行了研究。结果表明,在泌乳90d时所挤驼乳蛋白中Thr,Val,Met,Ile,Leu,Phe和Lys必需氨基酸的含量分别为4.52,6.20,3.16,5.61,9.48,4.73,7.75g/100g。驼乳蛋白质中的必需氨基酸构成和FAO/WHO的推荐值十分相近,驼乳蛋白质对人体具有很高的营养价值。  相似文献   

大麦杂种后代的赤霉病抗性变异及抗性与棱性的关系     

吴基日  刘宪虎  许明子  李艳茹 《延边大学农学学报》1996,(4)

本文用５个二棱大麦“抗性强×抗性中”组合的Ｆ_６集团和４个“二棱抗性弱×六棱抗性中”组合的１１３个Ｆ_７系统以及５０对二棱和六棱近等基因系，进行了大麦赤霉病的抗性鉴定及遗传分析，结果表明：大麦赤霉病抗性受具有累加效应的微效多基因系统的控制，其广义遗传力为０．６０；二棱系统的抗性比六棱系统强，但控制抗性的基因和棱型基因之间连锁的可能性很小。  相似文献   

Induction of heme oxygenase-1 by Macleaya cordata extract and its constituent sanguinarine in RAW264.7 cells     

Vrba J  Orolinova E  Ulrichova J 《Fitoterapia》2012,83(2):329-335

Macleaya cordata (plume poppy) is used in traditional Chinese medicine for its anti-inflammatory and antibacterial activities. In this study, we examined whether M. cordata extract and/or its major alkaloid constituents, protopine, allocryptopine, sanguinarine and chelerythrine activate the Nrf2 signalling pathway which regulates the expression of cytoprotective enzymes including heme oxygenase-1 (HO-1) and thioredoxin 1. In murine macrophage RAW264.7 cells, M. cordata extract increased both mRNA and protein levels of HO-1. Of the alkaloids examined, only sanguinarine appeared to be responsible for these effects. At the concentration of 2 μM, sanguinarine induced nuclear accumulation of Nrf2, increased the expression of Hmox1 gene encoding HO-1 and elevated HO-1 protein levels. Sanguinarine-induced Hmox1 mRNA expression was suppressed by SB203580, a pharmacologic inhibitor of p38 mitogen-activated protein kinases (p38 MAPKs). The upregulation of HO-1 in RAW264.7 cells by sanguinarine was, however, accompanied by decrease in cell viability. Nonetheless, sanguinarine at micromolar, non-cytotoxic concentrations elevated protein levels of HO-1 and thioredoxin 1 in primary cultures of human hepatocytes. We conclude that sanguinarine may, under appropriate conditions, increase the capacity of the enzymatic antioxidant defence system via activation of the p38 MAPK/Nrf2 pathway.  相似文献   

Reinforcement of wet milled jute nano/micro particles in polyvinyl alcohol films     

Vijay Baheti  Jiri Militky 《Fibers and Polymers》2013,14(1):133-137

Textile industry generate significant amount of waste fibres in form of short lengths during mechanical processing. However these short fibres possess excellent properties suitable for many other applications. The objective of this work was to use them for the preparation of nanoparticles/nanofibres as fillers in biodegradable composite applications such as food packaging, agriculture mulch films, automotive plastics, etc. The present paper concerns with jute fibres as a source of nanocellulose for reinforcement of PVA mulch films. Jute fibres were first refined to micro/nanoscale particles in form of nanofibrillar cellulose (NFC) by high energy planetary ball milling process in dry and wet condition. Wet milling was observed more efficient than dry milling in terms of unimodality of size distribution with reduction in size below 500 nm after milling for 3 hours. Later the obtained particles were used as fillers in Poly vinyl alcohol (PVA) films and their reinforcement evaluated based on thermal properties. It was observed that glass transition temperature (T_g) of PVA films improved from 84.36 °C to 95.22 °C after addition of 5 % jute particles without affecting % crystallinity and melting temperature (T _m) of PVA. Dynamic mechanical analysis of composite films with 5 % jute particles showed higher value of 14×10⁸ Pa for storage modulus in comparison to 9×10⁸ Pa of neat composite film. The percolation effect was observed more above glass transition temperature which consequently resulted in improved transfer of stiffness from jute particles to PVA matrix above 50 °C. The percolation phenomena also explained the improvement in thermal stability by 10 °C for every increased loading of jute particles due to formation of hydrogen bonds with PVA matrix.  相似文献   

Surface modification of polymer optical fibers for enhanced side emission behavior     

Rajesh Mishra  Anuj Shukla  Dana Kremenakova  Jiri Militky 《Fibers and Polymers》2013,14(9):1468-1471

The polymer optical fiber with trade name Flexi was used in this research, because of its flexibility and the range of diameters available in the market. These fibers were dyed using commercial disperse dye under various conditions of dye concentration and dyeing time. Samples were analyzed for side emission of light with the use of an instrument which was specifically designed for the measurement of this nature. The results showed that the dye penetration is dependent on time, if dye concentration and temperature are kept constant. After 40 min of dyeing, the fiber core showed an increase in side emission with lower loss due to attenuation. Excessive time in the hot conditions also degraded the fiber, so that the fiber became very stiff and brittle. Fibers were also subjected to heat, in the form of boiling water bath, for selected periods of time, and it was found that the effect was similar to that of the prior experiments. Surface treatment of Flexi fibers was carried out using ethyl acetate as an etching agent, to possibly accept more disperse dye on the fiber surface. The results after dyeing showed a more significant improvement in both side emission and attenuation of light.  相似文献   

Cytokine response of porcine cell lines to Salmonella enterica serovar typhimurium and its hilA and ssrA mutants     

Volf J  Boyen F  Faldyna M  Pavlova B  Navratilova J  Rychlik I 《Zoonoses and public health》2007,54(8):286-293

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a facultative intracellular bacterium which can infect and colonize pigs. After contact with enterocytes and macrophages, S. Typhimurium induces production of cytokines thus triggering the innate immune response. In this study we evaluated the cytokine response of two porcine cell lines, IPI-2I and 3D4/31, of epithelial or macrophage origins, respectively, to the wild-type S. Typhimurium and its hilA and ssrA mutants. We observed that the 3D4/31 cell line essentially did not respond to S. Typhimurium infection when a medium with foetal calf serum was used. However when the 3D4 cell line was incubated overnight in the presence of porcine serum, it efficiently responded to the wild-type strain and the ssrA mutant but not to the noninvasive hilA mutant as measured by mRNA quantification of TNF-alpha, IL-8 and GM-CSF by the real-time RT-PCR. In IPI-2I, all the cytokines were also induced by the wild-type S. Typhimurium and the ssrA mutant although the induction of TNF-alpha was lower than that induced by the wild-type strain. The hilA mutant was unable to induce any of the cytokines tested. The ssrA mutant can therefore be considered as more suitable for further vaccine development as the stimulation of innate immune response is important for animal protection against a challenge with virulent strains.  相似文献