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31.
Maternal transfer of androgens in eggs is affected by food supplementation but not by predation risk 下载免费PDF全文
Chiara Morosinotto Robert L. Thomson Suvi Ruuskanen Erkki Korpimäki Esa Lehikoinen Erich Möstl Toni Laaksonen 《Journal of avian biology》2016,47(5):629-641
Mothers may affect the future success of their offspring by varying allocation to eggs and embryos. Allocation may be adaptive based on the environmental conditions perceived during early breeding. We investigated the effects of food supplementation and predation risk on yolk hormone transfer in the pied flycatcher Ficedula hypoleuca. In a food supplementation experiment, females were food‐supplemented prior to and during egg‐laying and androgen concentrations were measured throughout the laying order. Predation risk was investigated in three different studies combining both correlative data, where flycatchers bred in close proximity to two different predator species that prey upon adult flycatchers (either Tengmalm's owl Aegolius funereus or pygmy owl Glaucidium passerinum), and an experimental manipulation, where flycatchers were exposed to cues of a nest predator (least weasel Mustela nivalis). Females receiving food supplementation laid eggs with lower concentrations of androstenedione (A4) than females not receiving food supplements. Yolk testosterone (T) concentration showed the same pattern but the difference was not statically significant. Testosterone (but not A4) concentration increased within clutches, from the first to the last egg, independently of the food supplementation. Females breeding under high predation risk did not differ from control females in their yolk androgen levels (A4, T or progesterone). However, concentrations of A4 tended to be lower in the proximity of pygmy owls, which could indirectly increase offspring survival after fledging. Food supplementation during egg‐laying seems to have a stronger impact on maternal transfer of androgens than predation risk. Food availability and predation risk could differentially affect the trade‐offs of androgen allocation for the offspring when raised in good vs. dangerous environments. 相似文献
32.
Musculoskeletal anatomy of the Eurasian lynx,Lynx lynx (Carnivora: Felidae) forelimb: Adaptations to capture large prey? 下载免费PDF全文
Mammalian carnivores adhere to two different feeding strategies relative to their body masses. Large carnivores prey on animals that are the same size or larger than themselves, whereas small carnivores prey on smaller vertebrates and invertebrates. The Eurasian lynx (Lynx lynx) falls in between these two categories. Lynx descend from larger forms that were probably large prey specialists, but during the Pleistocene became predators of small prey. The modern Eurasian lynx may be an evolutionary reversal toward specializing in large prey again. We hypothesized that the musculoskeletal anatomy of lynx should show traits for catching large prey. To test our hypothesis, we dissected the forelimb muscles of six Eurasian lynx individuals and compared our findings to results published for other felids. We measured the bones and compared their dimensions to the published material. Our material displayed a well‐developed pectoral girdle musculature with some uniquely extensive muscle attachments. The upper arm musculature resembled that of the pantherine felids and probably the extinct sabertooths, and also the muscles responsible for supination and pronation were similar to those in large cats. The muscles controlling the pollex were well‐developed. However, skeletal indices were similar to those of small prey predators. Our findings show that lynx possess the topographic pattern of muscle origin and insertion like in large felids. J. Morphol. 277:753–765, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
33.
Jin Luo Elena Efimova Daniel Christoph Volke Ville Santala Suvi Santala 《Microbial biotechnology》2022,15(11):2800-2818
Microbial production of intracellular compounds can be engineered by redirecting the carbon flux towards products and increasing the cell size. Potential engineering strategies include exploiting clustered regularly interspaced short palindromic repeats interference (CRISPRi)-based tools for controlling gene expression. Here, we applied CRISPRi for engineering Acinetobacter baylyi ADP1, a model bacterium for synthesizing intracellular storage lipids, namely wax esters. We first established an inducible CRISPRi system for strain ADP1, which enables tightly controlled repression of target genes. We then targeted the glyoxylate shunt to redirect carbon flow towards wax esters. Second, we successfully employed CRISPRi for modifying cell morphology by repressing ftsZ, an essential gene required for cell division, in combination with targeted knock-outs to generate significantly enlarged filamentous or spherical cells respectively. The engineered cells sustained increased wax ester production metrics, demonstrating the potential of cell morphology engineering in the production of intracellular lipids. 相似文献
34.
Esmail Dehghan Suvi T. H?kkinen Kirsi-Marja Oksman-Caldentey Farajollah Shahriari Ahmadi 《Plant Cell, Tissue and Organ Culture》2012,110(1):35-44
In this study, the effects of ploidy level and culture medium were studied on the production of tropane alkaloids. We have successfully produced stable tetraploid hairy root lines of Hyoscyamus muticus and their ploidy stability was confirmed 30?months after transformation. Tetraploidy affected the growth rate and alkaloid accumulation in plants and transformed root cultures of Egyptian henbane. Although tetraploid plants could produce 200% higher scopolamine than their diploid counterparts, this result was not observed for corresponding induced hairy root cultures. Culture conditions did not only play an important role for biomass production, but also significantly affected tropane alkaloid accumulation in hairy root cultures. In spite of its lower biomass production, tetraploid clone could produce more scopolamine than the diploid counterpart under similar growth conditions. The highest yields of scopolamine (13.87?mg?l?1) and hyoscyamine (107.7?mg 1?1) were obtained when diploid clones were grown on medium consisting of either Murashige and Skoog with 60?g/l sucrose or Gamborg??s B5 with 40?g/l sucrose, respectively. Although the hyoscyamine is the main alkaloid in the H. muticus plants, manipulation of ploidy level and culture conditions successfully changed the scopolamine/hyoscyamine ratio towards scopolamine. The fact that hyoscyamine is converted to scopolamine is very important due to the higher market value of scopolamine. 相似文献
35.
Häkkinen ST Lackman P Nygrén H Oksman-Caldentey KM Maaheimo H Rischer H 《Journal of biotechnology》2012,157(2):287-294
The aim of this study was to use whole cell catalysts as tools for modification of selected resin acids in order to obtain value-added functional derivatives. The enzymatic bioconversion capacities of two plant species were tested towards dehydroabietic acid. Dehydroabietic acid (DHA) is an abundant resin acid in conifers, representing a natural wood protectant. It is also one of the constituents found in by-products of the kraft chemical pulping industry. DHA was fed to tobacco (Nicotiana tabacum) and Madagascar periwinkle (Catharanthus roseus) plant cell and tissue cultures and bioconversion product formation was monitored using NMR analysis. Both plant species took up DHA from culture medium, and various types of typical detoxification processes occurred in both cultures. In addition, diverse responses to DHA treatment were observed, including differences in uptake kinetics, chemical modification of added substrate and changes in overall metabolism of the cells. Interestingly, Catharanthus roseus, a host species for pharmaceutically valuable terpenoid indole alkaloids, exhibited a very different bioconversion pattern for exogenously applied DHA than tobacco, which does not possess a terpenoid indole pathway. In tobacco, DHA is readily glycosylated in the carbonyl group, whereas in periwinkle it is proposed that a cytochrome P450-catalyzed enzymatic detoxification reaction takes place before the formation of glycosylated product. 相似文献
36.
Glycomics of bone marrow-derived mesenchymal stem cells can be used to evaluate their cellular differentiation stage 总被引:1,自引:0,他引:1
Annamari Heiskanen Tia Hirvonen Hanna Salo Ulla Impola Anne Olonen Anita Laitinen Sari Tiitinen Suvi Natunen Olli Aitio Halina Miller-Podraza Manfred Wuhrer André M. Deelder Jari Natunen Jarmo Laine Petri Lehenkari Juhani Saarinen Tero Satomaa Leena Valmu 《Glycoconjugate journal》2009,26(3):367-384
Human mesenchymal stem cells (MSCs) are adult multipotent progenitor cells. They hold an enormous therapeutic potential, but
at the moment there is little information on the properties of MSCs, including their surface structures. In the present study,
we analyzed the mesenchymal stem cell glycome by using mass spectrometric profiling as well as a panel of glycan binding proteins.
Structural verifications were obtained by nuclear magnetic resonance spectroscopy, mass spectrometric fragmentation, and glycosidase
digestions. The MSC glycome was compared to the glycome of corresponding osteogenically differentiated cells. More than one
hundred glycan signals were detected in mesenchymal stem cells and osteoblasts differentiated from them. The glycan profiles
of MSCs and osteoblasts were consistently different in biological replicates, indicating that stem cells and osteoblasts have
characteristic glycosylation features. Glycosylation features associated with MSCs rather than differentiated cells included
high-mannose type N-glycans, linear poly-N-acetyllactosamine chains and α2-3-sialylation. Mesenchymal stem cells expressed SSEA-4 and sialyl Lewis x epitopes. Characteristic
glycosylation features that appeared in differentiated osteoblasts included abundant sulfate ester modifications. The results
show that glycosylation analysis can be used to evaluate MSC differentiation state. 相似文献
37.
Natalia Pitala Suvi Ruuskanen Toni Laaksonen Blandine Doligez Barbara Tschirren Lars Gustafsson 《Journal of avian biology》2009,40(2):225-230
Hormone-mediated maternal effects may be an important mechanism for adjusting offspring phenotype to particular requirements of the environment. We manipulated the levels of testosterone and androstenedione in the yolk of collared flycatcher Ficedula albicollis eggs to investigate the effects of pre-natal exposure to androgens on growth and immune function. Androgen treatment tended to reduce the growth of males, and enhance the growth of females, as indicated by significant interaction between sex and androgen treatment. Cellular immune function was not affected by androgen treatment or sex. Survival of nestlings until fledging was not related to androgen treatment. Our results indicate that in the collared flycatcher yolk androgens do not involve clear overall benefits during the nestling stage, and that growth-enhancing effects of increased yolk androgen levels on female nestlings are counterbalanced by detrimental effects on male nestlings. 相似文献
38.
Jaana Vuosku Suvi Sutela Eila Tillman-Sutela Anneli Kauppi Anne Jokela Tytti Sarjala Hely H?ggman 《Plant signaling & behavior》2009,4(10):928-932
In plants, programmed cell death (PCD) is an important mechanism that controls normal growth and development as well as many defence responses. At present, research on PCD in different plant species is actively carried out due to the possibilities offered by modern methods in molecular biology and the increasing amount of genome data. The pine seed provides a favourable model for PCD because it represents an interesting inheritance of seed tissues as well as an anatomically well-described embryogenesis during which several tissues die via morphologically different PCD processes.Key words: conifer, developmental cell death, embryogenesis, megagametophyte, necrotic cell death, pine, seed development 相似文献
39.
Marko T. Ahonen Iulia Diaconu Sari Pesonen Anna Kanerva Marc Baumann Suvi T. Parviainen Brad Spiller Vincenzo Cerullo Akseli Hemminki 《PloS one》2010,5(9)
Background
Adenoviruses are attractive vectors for gene therapy because of their stability in vivo and the possibility of production at high titers. Despite exciting preclinical data with various approaches, there are only a few examples of clear efficacy in clinical trials. Effective gene delivery to target cells remains the key variable determining efficacy and thus enhanced transduction methods are important.Methods/Results
We found that heated serum could enhance adenovirus 5 mediated gene delivery up to twentyfold. A new protein-level interaction was found between fiber knob and serum transthyretin, but this was not responsible for the observed effect. Instead, we found that heating caused the calcium and phosphate present in the serum mix to precipitate, and this was responsible for enhanced gene delivery. This finding could have relevance for designing preclinical experiments with adenoviruses, since calcium and phosphate are present in many solutions. To translate this into an approach potentially testable in patients, we used calcium gluconate in phosphate buffered saline, both of which are clinically approved, to increase adenoviral gene transfer up to 300-fold in vitro. Gene transfer was increased with or without heating and in a manner independent from the coxsackie-adenovirus receptor. In vivo, in mouse studies, gene delivery was increased 2-, 110-, 12- and 13-fold to tumors, lungs, heart and liver and did not result in increased pro-inflammatory cytokine induction. Antitumor efficacy of a replication competent virus was also increased significantly.Conclusion
In summary, adenoviral gene transfer and antitumor efficacy can be enhanced by calcium gluconate in phosphate buffered saline. 相似文献40.
Capsaicin contributes to the organoleptic attributes of hot peppers. Here, we show that capsaicin is utilized as a growth nutrient by certain bacteria. Enrichment cultures utilizing capsaicin were successfully initiated using Capsicum-derived plant material or leaves of tomato (a related Solanaceae) as inocula. No other sources of inoculum examined yielded positive enrichments. Of 25 isolates obtained from enrichments: all utilized 8-methylnonanoic acid; nine were found capable of degrading capsaicin as sole carbon and energy source; 11 were found capable of utilizing vanillylamine; but only two strains could use either of these latter two compounds as sole nitrogen source. Phylogenetic analysis of capsaicin degraders revealed them to be strains of Variovorax and Ralstonia, whereas the vanillylamine degraders were strains of Pseudomonas and Variovorax. Neither of the two strains isolated from one enrichment culture originally inoculated with dried pepper fruit was capable of using capsaicin as sole carbon and nitrogen source. However, good growth was achieved under such conditions when the two isolates, a strain of Variovorax paradoxusThat degraded capsaicin when provided with ammonium, and a vanillylamine degrading strain of Pseudomonas putida, were cultured together. A cross-feeding of capsaicin-derived carbon and nitrogen between members of pepper-associated consortia is proposed. 相似文献