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41.
Apoptosis within bovine follicular cells and its effect on oocyte development during in vitro maturation 总被引:10,自引:0,他引:10
Developmental competence of oocytes is compromised if they originate from atretic follicles. Apoptosis is the underlying process of atresia. Apoptotic changes in follicular cells are thought to influence the outcome of IVF. The aim of this study was to investigate apoptosis in different compartments of single bovine follicles (follicular wall, granulosa and cumulus cells (CC)) in relation to COC morphology, and to determine whether the addition, in vitro, of exogenous follicular cells from atretic follicles to maturing cumulus oocyte complexes (COCs) influenced the development of oocytes.Antral follicles were dissected from bovine ovaries and opened to obtain COCs and free floating granulosa cells (GC). The COCs were classified according to morphology. Apoptosis was determined in cumulus and granulosa cells and in homogenates of the remaining follicular wall.For every morphological class of COCs, a large variability of apoptotic expression was found in all follicle compartments. Follicular wall apoptosis was not correlated to COC morphology or to the percentage of apoptotic granulosa or cumulus cells. In grade 1 (best morphology) COCs, the degree of apoptosis in granulosa cells was comparable to cumulus cell apoptosis (P<0.01). The overall expression of apoptosis in granulosa cells of follicles containing grade 3 COCs (median+/-median absolute deviation: 37.8+/-13.8%) was significantly higher (P<0.05) than in follicles with grade 1 (22.7+/-10.4%) or grade 2 COCs (20.0+/-17.0%). About 48.3% of grade 3 COCs possessed strongly apoptotic cumulus cells compared to 27.8 and 28.2% of grade 1 or grade 2 COCs, respectively. Nonapoptotic cumulus complexes were observed in grades 1 and 2 COCs only.Adding exogenous follicular cells from atretic follicles to bovine COCs (grades 1 and 2) during in vitro maturation (IVM) had no impact on fertilization, blastocyst formation or hatching after IVF. This is of particular practical relevance to embryo production after ovum pick up (OPU), as during this process, good quality COCs are cultured together with simultaneously collected slightly atretic COCs. 相似文献
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Checker mallows (Sidalcea, Malvaceae) constitute a western North American genus of annuals and perennials that have been regarded as taxonomically difficult because of complex patterns of morphological variation putatively stemming from hybridization and polyploidy. In recent molecular phylogenetic investigations extensive polymorphism was observed in the internal and external transcribed spacers (ITS and ETS) of 18S-26S nuclear ribosomal DNA for some Sidalcea samples. To resolve the evolutionary basis for this polymorphism and to readdress the evolutionary impact of hybridization in Sidalcea we cloned and sequenced the polymorphic DNAs and included the clones in phylogenetic analyses together with direct sequences of non-polymorphic samples. The positions of cloned spacer sequences in the phylogenetic trees suggest that S. reptans and two subspecies of S. malviflora may have been influenced by past hybridization with lineages of the "glaucescens" clade. Polymorphic sequence patterns in other taxa may be a result of extensive interbreeding within young clades, in keeping with the minimal sequence divergence, largely overlapping geographic distributions and morphology, and ploidy variation in these groups. Other possible explanations for polymorphic sequences in members of Sidalcea include slow concerted evolution relative to mutation rates, incomplete lineage sorting, and recent pseudogene formation. 相似文献
43.
Dijana?Krsti? Teodora?Jankovi? Katarina??avikin-Fodulovi?Email author Neboj?a?Menkovi? Dragoljub?Grubi?i? 《In vitro cellular & developmental biology. Plant》2003,39(2):203-207
Summary The qualitative and quantitative composition of secondary metabolites was studied in the shoots and roots of Centaurium pulchellum cultured in vitro. Secoiridoids (gentiopierin, swertiamarin, and sweroside) and xanthones (methylbellidifolin, demethyleustomin, and deccussatin)
were isolated. Sweroside was found to be the major secoiridoid compound in the aerial parts of plants growing in nature. while
swertiamarin dominated in plants cultured in vitro. In roots of all plants, genciopicrin was the major compound. Xanthone demethyleustomin was the major compound both in the
shoots and roots of plants growing in nature and cultured in vitro. Different sugars (glucose, fructose, and sucrose) added in different concentrations in the medium affected the production
of secondary compounds. 相似文献
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Freek?Cox Eirikur?SaelandEmail author Matthijs?Baart Martin?Koldijk Jeroen?Tolboom Liesbeth?Dekking Wouter?Koudstaal Karin?L?vgren Bengtsson Jaap?Goudsmit Katarina?Rado?evi? 《Virology journal》2015,12(1):210
Background
Influenza virus infections are responsible for significant morbidity worldwide and therefore it remains a high priority to develop more broadly protective vaccines. Adjuvation of current seasonal influenza vaccines has the potential to achieve this goal.Methods
To assess the immune potentiating properties of Matrix-M?, mice were immunized with virosomal trivalent seasonal vaccine adjuvated with Matrix-M?. Serum samples were isolated to determine the hemagglutination inhibiting (HAI) antibody titers against vaccine homologous and heterologous strains. Furthermore, we assess whether adjuvation with Matrix-M? broadens the protective efficacy of the virosomal trivalent seasonal vaccine against vaccine homologous and heterologous influenza viruses.Results
Matrix-M? adjuvation enhanced HAI antibody titers and protection against vaccine homologous strains. Interestingly, Matrix-M? adjuvation also resulted in HAI antibody titers against heterologous influenza B strains, but not against the tested influenza A strains. Even though the protection against heterologous influenza A was induced by the adjuvated vaccine, in the absence of HAI titers the protection was accompanied by severe clinical scores and body weight loss. In contrast, in the presence of heterologous HAI titers full protection against the heterologous influenza B strain without any disease symptoms was obtained.Conclusion
The results of this study emphasize the promising potential of a Matrix-M?-adjuvated seasonal trivalent virosomal influenza vaccine. Adjuvation of trivalent virosomal vaccine does not only enhance homologous protection, but in addition induces protection against heterologous strains and thus provides overall more potent and broad protective immunity.48.
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Gabriel Minarik Gabriela Repiska Michaela Hyblova Emilia Nagyova Katarina Soltys Jaroslav Budis Frantisek Duris Rastislav Sysak Maria Gerykova Bujalkova Barbora Vlkova-Izrael Orsolya Biro Balint Nagy Tomas Szemes 《PloS one》2015,10(12)