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B. Nzau Matondo A. B. Nlemvo M. Ovidio P. Poncin J. C. Philippart 《Zeitschrift fur angewandte Ichthyologie》2008,24(1):63-67
Fertility in first‐generation hybrids of roach, Rutilus rutilus, and silver bream, Blicca bjoerkna, was investigated. Sperm and egg production of hybrids at first sexual maturity were examined. Eggs from female hybrids were artificially fertilized with the sperm of a corresponding hybrid male; a hybrid male from the reciprocal crossbreeding; a parental species male R. rutilus; and a parental species male B. bjoerkna. The results revealed that gametogenesis was normal in female hybrids. However, in male hybrids, a low efficiency of gametogenesis was observed. The semen of male hybrids was extremely dilute, with spermatozoa concentration lower than that in parental species. Nevertheless, these F1 hybrids (males and females) from reciprocal crossbreeding were fertile. F2 and backcross generations were produced, but F2 crosses from the female hybrid and corresponding hybrid male displayed a drastically slower hatching rate. Also higher proportions of deformed embryos were hatched than in other post‐F1‐generation crosses. 相似文献
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The evaluation of biomarkers in bodily fluids necessitates the development of robust methods to quantify proteins in a complex background, using large sets of samples. The ability to multiplex numerous analytes in a single assay expedites the process. Liquid chromatography-mass spectrometry (LC-MS) analyses performed in selected reaction monitoring (SRM) in conjunction with stable isotope dilution MS present an effective way to detect and quantify biomarker candidates in bodily fluids. The strategy presented involves an initial qualification of predefined sets of proteins in urine. The technique was applied to detect and quantify peptides in urine samples as surrogates for a few endogenous proteins. Multiplexed assays were developed to analyze proteins associated with bladder cancer; a few exogenous proteins were added as internal standards. The sample preparation and the analytical protocols were optimized to ensure reproducibility, analytical precision, and quantification limits in the low nanogram per milliliter range. Analyses were performed using known amounts of isotopically labeled peptides. Systematic replication of the measurements indicated intra-assay and inter-assay variability, with CVs in the range of 10%. The differences measured for two targeted proteins were correlated with their level of expression in the corresponding tumors using immunohistochemistry. 相似文献
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Nzau Joslyn Muthio Ulrich Werner Rieckmann Marco Habel Jan Christian 《Biodiversity and Conservation》2022,31(4):1313-1328
Biodiversity and Conservation - Numerous conservation activities in Africa have been of little effect. In this study, we investigate socio-economic trade-offs that might have been overlooked, yet... 相似文献
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Froment C Uttenweiler-Joseph S Bousquet-Dubouch MP Matondo M Borges JP Esmenjaud C Lacroix C Monsarrat B Burlet-Schiltz O 《Proteomics》2005,5(9):2351-2363
Mammalian proteasomes are macromolecular complexes formed of a catalytic 20S core associated to two regulatory complexes. The 20S core complex consists of four stacked rings of seven alpha or beta subunits. Three beta subunits contain a catalytic site and can be replaced by three interferon gamma-inducible counterparts to form the immunoproteasome. Cells may constitutively possess a mixture of both 20S proteasome types leading to a heterogeneous proteasome population. Purified rat 20S proteasome has been separated in several chromatographic fractions indicating an even higher degree of complexity in 20S proteasome subunit composition. This complexity may arise from the presence of subunit isoforms, as previously detected in purified human erythrocyte 20S proteasome. In this study, we have used a quantitative proteomic approach based on two-dimensional gel electrophoresis and isotope-coded affinity tag (ICAT) labeling to quantify the variations in subunit composition, including subunit isoforms, of 20S proteasomes purified from different cells. The protocol has been adapted to the analysis of low quantities of 20S proteasome complexes. The strategy has then been validated using standard proteins and has been applied to the comparison of 20S proteasomes from erythrocytes and U937 cancer cells. The results obtained show that this approach represents a valuable tool for the study of 20S proteasome heterogeneity. 相似文献
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B. Nzau Matondo M. Ovidio J. C. Philippart P. Poncin 《Zeitschrift fur angewandte Ichthyologie》2011,27(3):859-867
The aim of this study was to further test the viability of the roach Rutilus rutilus × common bream Abramis brama hybrid in terms of reproductive behaviour and sexual production. Egg release, mating and aggressive acts in reproductive behaviour, as well as absolute fecundity and sperm density in milt for sexual production were examined in the first generation of these hybrids at their first sexual maturity. The F2 and backcrosses of hybrids were also studied. The results revealed that these hybrids expressed a normal and typical mating behaviour, producing viable gametes. Under experimental reproduction between hybrids (hybrid reproduction), the number of egg‐release acts (range, 21–66) was nearer (χ2 test, P > 0.05) the number of mating acts (11–65). Moreover, hybrid males exhibited territorial and aggressive behaviours. However, in experimental reproduction of female and male hybrids mixed with parental males (mixed reproduction), the egg‐release act and the mating act were inhibited by the intense territorial and aggressive activities of the common bream male. Absolute fecundity values (median, <2.2 × 103 eggs) and sperm density (<7 × 109 spermatozoa ml?1) of hybrids showed a greater decrease (U test, P < 0.05) than in parental species (median, >6.0 × 103 eggs and >14 × 109 spermatozoa ml?1, respectively). Nevertheless, these hybrids were fertile. F2 and backcross generations were produced, although with a significantly lower viable hatching rate (FEP test, P < 0.05) in F2 individuals from the female and its corresponding hybrid male (<6%), indicating a very low chance of survival in rivers. 相似文献
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Arturo Aguilar‐Rojas Silvia Castellanos‐Castro Mariette Matondo Quentin Giai Gianetto Hugo Varet Odile Sismeiro Rachel Legendre Julien Fernandes David Hardy Jean‐Yves Coppe Jean‐Christophe Olivo‐Marin Nancy Guillen 《Cellular microbiology》2020,22(8)
Entamoeba histolytica is the causative agent of amebiasis, an infectious disease targeting the intestine and the liver in humans. Two types of intestinal infection are caused by this parasite: silent infection, which occurs in the majority of cases, and invasive disease, which affects 10% of infected persons. To understand the intestinal pathogenic process, several in vitro models, such as cell cultures, human tissue explants or human intestine xenografts in mice, have been employed. Nevertheless, our knowledge on the early steps of amebic intestinal infection and the molecules involved during human–parasite interaction is scarce, in part due to limitations in the experimental settings. In the present work, we took advantage of tissue engineering approaches to build a three‐dimensional (3D)‐intestinal model that is able to replicate the general characteristics of the human colon. This system consists of an epithelial layer that develops tight and adherens junctions, a mucus layer and a lamina propria‐like compartment made up of collagen containing macrophages and fibroblast. By means of microscopy imaging, omics assays and the evaluation of immune responses, we show a very dynamic interaction between E. histolytica and the 3D‐intestinal model. Our data highlight the importance of several virulence markers occurring in patients or in experimental models, but they also demonstrate the involvement of under described molecules and regulatory factors in the amoebic invasive process. 相似文献