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11.
Infection with Methorchis bilis was recognized for the first time in the residents of Novosibirsk area (Russia). During a serological survey (37 patients in toto), it was possible to demonstrate that 48.5% of the serum samples tested possessed antibodies to Opisthorchis felineus antigens, 37.8% to both Opisthorchis felineus and Methorchis bilis antigens, and 13.5% to Methorchis bilis antigens only. 相似文献
12.
Competing death programs in poliovirus-infected cells: commitment switch in the middle of the infectious cycle 总被引:5,自引:0,他引:5 下载免费PDF全文
Agol VI Belov GA Bienz K Egger D Kolesnikova MS Romanova LI Sladkova LV Tolskaya EA 《Journal of virology》2000,74(12):5534-5541
Productive poliovirus infection of HeLa cells leads to the canonical cytopathic effect (CPE), whereas certain types of abortive infection result in apoptosis. To define the time course of commitment to the different types of poliovirus-induced death, inhibitors of viral replication (guanidine HCl) or translation (cycloheximide) were added at different times postinfection (p.i.). Early in the infection (during the first approximately 2 h p.i.), predominantly proapoptotic viral function was expressed, rendering the cells committed to apoptosis, which developed several hours after viral expression was arrested. In the middle of infection, concomitantly with the onset of fast generation of viral progeny, the implementation of the viral apoptotic program was abruptly interrupted. In particular, activation of an Asp-Glu-Val-Asp (DEVD)-specific caspase(s) occurring in the apoptosis-committed cells was prevented by the ongoing productive infection. Simultaneously, the cells retaining normal or nearly normal morphology became committed to CPE, which eventually developed regardless of whether or not further viral expression was allowed to proceed. The implementation of the poliovirus-induced apoptotic program was suppressed in HeLa cells overexpressing the Bcl-2 protein, indicating that the fate of poliovirus-infected cells depends on the balance of host and viral pro- and antiapoptotic factors. 相似文献
13.
A study was made of the effect of gamma-irradiation of collalitin samples with doses of 25 and 50 kGy on proteolytic and enzyme activity with respect to denaturated collagen. The enzyme properties were found to change upon storage for periods of 6 and 12 months at 15 degrees C under unsterile conditions. No significant changes in the molecular mass of the collalitin samples were revealed by the method of gell-chromatography after irradiation and storage. 相似文献
14.
15.
The kinetics of changes in the resistance of a green leaf by the action of exciting light was studied. It was shown that the illumination-induced changes in leaf conductance are mainly due to an elevation of temperature caused by the absorption of light energy. Based on the experimental results, the fraction of absorbed light energy converted into heat calculated under assumption that heating of the leaf across the thickness is uniform. It was found that the fraction of absorbed energy converted into heat does not depend on the intensity of radiation in the IR range and increases with decreasing intensity of photosynthetically active radiation. An explanation of the phenomenon is proposed, which is based on that in reality the heating of the leaf across the thickness is nonhomogeneous and this inhomogeneity of heating becomes more pronounced upon photoinduced changes in absorption resulting from a decrease in photosynthetically active radiation. It was shown that nonphotochemical fluorescence quenching does not substantially affect the leaf conductance at intensities of photosynthetically active radiation not higher than 200 Wt/m2. 相似文献
16.
The Tasmanian devil (Sarcophilus harrisii) is currently threatened by an emerging wildlife disease, devil facial tumour disease. The disease is decreasing devil numbers dramatically and may lead to the extinction of the species. At present, nothing is known about the immune genes or basic immunology of the devil. In this study, we report the construction of the first genetic library for the Tasmanian devil, a spleen cDNA library, and the isolation of full-length MHC Class I and Class II genes. We describe six unique Class II beta chain sequences from at least three loci, which belong to the marsupial Class II DA gene family. We have isolated 13 unique devil Class I sequences, representing at least seven Class I loci, two of which are most likely non-classical genes. The MHC Class I sequences from the devil have little heterogeneity, indicating recent divergence. The MHC genes described here are most likely involved in antigen presentation and are an important first step for studying MHC diversity and immune response in the devil. 相似文献
17.
Torres AM Tsampazi M Kennett EC Belov K Geraghty DP Bansal PS Alewood PF Kuchel PW 《Amino acids》2007,32(1):63-68
Summary. Platypus venom contains an isomerase that reversibly interconverts the second amino-acid residue in some peptides between
the L-form and the D-form. The enzyme acts on the natriuretic peptides OvCNPa and OvCNPb, and on the defensin-like peptides DLP-2 and DLP-4, but
it does not act on DLP-1. While the isomerization of DLP-2 to DLP-4 is inhibited by the amino-peptidase inhibitor amastatin,
it is not affected by the leucine amino-peptidase inhibitor bestatin. The enzyme, that is only present in minute quantities
in an extract of the venom gland, is thermally stable up to 55 °C, and it was found by anion-exchange chromatography to be
acidic. Isolation of the isomerase was carried out by combined ion-exchange chromatography and reverse-phase high performance
liquid chromatography (HPLC). 相似文献
18.
Krul LP Volozhyn AI Belov DA Poloiko NA Artushkevich AS Zhdanok SA Solntsev AP Krauklis AV Zhukova IA 《Biomolecular engineering》2007,24(1):93-95
A possibility of poly-D,L-lactide modification by multiwall carbon nanotubes (MWCNT) has been shown. MWCNT were prepared from methane-air mixture upon atmospheric pressure without catalyst on high voltage atmospheric pressure discharge plasma set-up. According to scanning and transmission electronic microscope data carbon nanotubes diameters were within 12-60 nm. Quantities of MWCNT incorporated did not exceed 0.5%. Nanocomposites were obtained by sonification of mixture of a poly-D,L-lactide solution in chloroform and MWCNT followed by film casting on glass substrates. Tensile strength and thermomechanical properties of the dried composite films were investigated. Introduction of MWCNT into poly-D,L-lactide has been shown to cause the enhanced polymer stability to thermal oxidative destruction. Taking into account the results obtained one could anticipate that implants from nanocomposites of poly-D,L-lactide with MWCNT would be dispersed in a living organism more slowly as compared to implants from pure poly-D,L-lactide without additives. 相似文献
19.
Ancient antimicrobial peptides kill antibiotic-resistant pathogens: Australian mammals provide new options 总被引:1,自引:0,他引:1
Wang J Wong ES Whitley JC Li J Stringer JM Short KR Renfree MB Belov K Cocks BG 《PloS one》2011,6(8):e24030
Background
To overcome the increasing resistance of pathogens to existing antibiotics the 10×''20 Initiative declared the urgent need for a global commitment to develop 10 new antimicrobial drugs by the year 2020. Naturally occurring animal antibiotics are an obvious place to start. The recently sequenced genomes of mammals that are divergent from human and mouse, including the tammar wallaby and the platypus, provide an opportunity to discover novel antimicrobials. Marsupials and monotremes are ideal potential sources of new antimicrobials because they give birth to underdeveloped immunologically naïve young that develop outside the sterile confines of a uterus in harsh pathogen-laden environments. While their adaptive immune system develops innate immune factors produced either by the mother or by the young must play a key role in protecting the immune-compromised young. In this study we focus on the cathelicidins, a key family of antimicrobial peptide genes.Principal Finding
We identified 14 cathelicidin genes in the tammar wallaby genome and 8 in the platypus genome. The tammar genes were expressed in the mammary gland during early lactation before the adaptive immune system of the young develops, as well as in the skin of the pouch young. Both platypus and tammar peptides were effective in killing a broad range of bacterial pathogens. One potent peptide, expressed in the early stages of tammar lactation, effectively killed multidrug-resistant clinical isolates of Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii.Conclusions and Significance
Marsupial and monotreme young are protected by antimicrobial peptides that are potent, broad spectrum and salt resistant. The genomes of our distant relatives may hold the key for the development of novel drugs to combat multidrug-resistant pathogens. 相似文献20.