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91.
The temperature–size rule (TSR), which states that body size increases at lower developmental temperatures, appears to be
a near-universal law for ectotherms. Although recent studies seem to suggest that the TSR might be adaptive, the underlying
developmental mechanisms are thus far largely unknown. Here, we investigate temperature effects on life-history traits, behaviour
and physiology in the copper butterfly Lycaena tityrus in order to disentangle the mechanistic basis for the above rule. In L. tityrus the larger body size produced at a lower temperature was proximately due to a greater increase in mass, which was caused
by both behavioural and physiological mechanisms: a much-increased food intake and a higher efficiency in converting ingested
food into body matter. These mechanisms, combined with temperature-induced changes at the cellular level, may provide general
explanations for the TSR. Body fat and protein content increased in butterflies reared at the higher temperature, indicating
favourable growth conditions. As predicted from protandry theory, males showed reduced development times, caused by higher
growth rates compared to females. The latter was itself related to a higher daily food consumption, while the total food consumption
(due to the females’ longer developmental period) and assimilation was higher in females and may underly the sexual body size
dimorphism. 相似文献
92.
Adaptive and non‐adaptive evolution of trait means and genetic trait correlations for herbivory resistance and performance in an invasive plant 下载免费PDF全文
Karin Schrieber Sabrina Wolf Catherina Wypior Diana Höhlig Isabell Hensen Susanne Lachmuth 《Oikos》2017,126(4):572-582
The EICA‐hypothesis predicts that invading plants adapt to their novel environment by evolving increased performance and reduced resistance in response to the release from natural enemies, and assumes a resource allocation tradeoff among both trait groups as mechanistic basis of this evolutionary change. Using the plant Silene latifolia as a study system, we tested these predictions by investigating whether 1) invasive populations evolved lower resistance and higher performance, 2) this evolutionary change is indeed adaptive, and 3) there is a negative genetic correlation between performance and resistance (i.e. a tradeoff) in native and introduced individuals. Moreover, we sampled eight native and eight invasive populations and determined their population co‐ancestry based on neutral SSR‐markers. We performed controlled crossings to produce five sib‐groups per population and exposed them to increased and reduced levels of enemy attack in a full‐factorial experiment to estimate performance and resistance. With these data, we performed trait‐by‐trait comparisons between ranges with ‘animal models’ that account for population co‐ancestry to quantify the amount of variance in traits explained by non‐adaptive versus adaptive evolution. Moreover, we tested for genetic correlations among performance and resistance traits within sib‐groups. We found significant reductions in resistance and increases in performance in invasive versus native populations, which could largely be attributed to adaptive evolution. While we detected a non‐significant trend towards negative genetic performance × resistance correlations in native populations, invasive populations exhibited both significant and non‐significant positive correlations. In summary, these results do not support a shift of performance and resistance trait values along a tradeoff line in response to enemy release, as predicted by EICA. They rather suggest that the independent evolution of both traits is not constrained by a tradeoff, and that various selective agents (including resource availability) interact in shaping both traits and in weakening negative genetic correlations in the invaded habitat. 相似文献
93.
Intra- and interspecific hybridization in invasive Siberian elm 总被引:1,自引:0,他引:1
Heidi Hirsch Johanne Brunet Juan E. Zalapa Henrik von Wehrden Matthias Hartmann Carolin Kleindienst Brandon Schlautman Evsey Kosman Karsten Wesche Daniel Renison Isabell Hensen 《Biological invasions》2017,19(6):1889-1904
Hybridization creates unique allele combinations which can facilitate the evolution of invasiveness. Frequent interspecific hybridization between the Siberian elm, Ulmus pumila, and native elm species has been detected in the Midwestern United States, Italy and Spain. However, Ulmus pumila also occurs in the western United States and Argentina, regions where no native elm species capable of hybridizing with it occurs. We examined whether inter- or intraspecific hybridization could be detected in these regions. Nuclear markers and the program STRUCTURE helped detect interspecific hybridization and determine the population genetic structure in both the native and the two non-native ranges. Chloroplast markers identified sources of introduction into these two non-native ranges. No significant interspecific hybridization was detected between U. pumila and U. rubra in the western United States or between U. pumila and U. minor in Argentina and vice versa. However, the genetic findings supported the presence of intraspecific hybridization and high levels of genetic diversity in both non-native ranges. The evidence presented for intraspecific hybridization in the current study, combined with reports of interspecific hybridization from previous studies, identifies elm as a genus where both inter- and intraspecific hybridization may occur and help maintain high levels of genetic diversity potentially associated with invasiveness. 相似文献
94.
Eco-efficiency analysis by basf: the method 总被引:2,自引:0,他引:2
Peter Saling Andreas Kicherer Brigitte Dittrich-Krämer Rolf Wittlinger Winfried Zombik Isabell Schmidt Wolfgang Schrott Silke Schmidt 《The International Journal of Life Cycle Assessment》2002,7(4):203-218
Intention, Goal, Scope, Background BASF has developed the tool of eco-efficiency analysis to address not only strategic issues, but also issues posed by the
marketplace, politics and research. It was a goal to develop a tool for decision-making processes which is useful for a lot
of applications in chemistry and other industries. Objectives. The objectives were the development of a common tool, which
is usable in a simple way by LCA-experts and understandable by a lot of people without any experience in this field. The results
should be shown in such a way that complex studies are understandable in one view.
Methods The method belongs to the rules of ISO 14040 ff. Beyond these life cycle aspect costs, calculations are added and summarized
together with the ecological results to establish an eco-efficiency portfolio.
Results and Discussion The results of the studies are shown in a simple way, the eco-efficiency portfolio. Therefore, ecological data are summarized
in a special way as described in this paper. It could be shown that the weighting factors, which are used in our method, have
a negligible impact on the results. In most cases, the input data have an important impact on the results of the study. Conclusions.
It could be shown that the newly developed eco-efficiency analysis is a new tool, which is usable for a lot of problems in
decision-making processes. It is a tool which compares different alternatives of a defined customer benefit over the whole
life cycle.
Recommendations and Outlook This new method can be a helpful tool in different fields of the evaluation of product or process alternatives. It can be
used in research and development as well as in the optimization of customer processes and products. It is an analytical tool
for getting more sustainable processes and products in the future 相似文献
95.
96.
Isabell Bludau Sander Willems Wen-Feng Zeng Maximilian T. Strauss Fynn M. Hansen Maria C. Tanzer Ozge Karayel Brenda A. Schulman Matthias Mann 《PLoS biology》2022,20(5)
The recent revolution in computational protein structure prediction provides folding models for entire proteomes, which can now be integrated with large-scale experimental data. Mass spectrometry (MS)-based proteomics has identified and quantified tens of thousands of posttranslational modifications (PTMs), most of them of uncertain functional relevance. In this study, we determine the structural context of these PTMs and investigate how this information can be leveraged to pinpoint potential regulatory sites. Our analysis uncovers global patterns of PTM occurrence across folded and intrinsically disordered regions. We found that this information can help to distinguish regulatory PTMs from those marking improperly folded proteins. Interestingly, the human proteome contains thousands of proteins that have large folded domains linked by short, disordered regions that are strongly enriched in regulatory phosphosites. These include well-known kinase activation loops that induce protein conformational changes upon phosphorylation. This regulatory mechanism appears to be widespread in kinases but also occurs in other protein families such as solute carriers. It is not limited to phosphorylation but includes ubiquitination and acetylation sites as well. Furthermore, we performed three-dimensional proximity analysis, which revealed examples of spatial coregulation of different PTM types and potential PTM crosstalk. To enable the community to build upon these first analyses, we provide tools for 3D visualization of proteomics data and PTMs as well as python libraries for data accession and processing.A combination of the comprehensive structural predictions of AlphaFold2 and large-scale proteomics data on post-translational modifications (PTMs) reveals novel insights into the functional importance of PTMs, based on their structural context. 相似文献
97.
Lin Li Zheng Chang Jiangwei Sun Miguel GarciaArgibay Ebba Du Rietz Maja Dobrosavljevic Isabell Brikell Tomas Jernberg Marco Solmi Samuele Cortese Henrik Larsson 《World psychiatry》2022,21(3):452
Accumulating evidence suggests a higher risk for cardiovascular diseases among individuals with mental disorders, but very little is known about the risk for overall and specific groups of cardiovascular diseases in people with attention‐deficit/hyperactivity disorder (ADHD). To fill this knowledge gap, we investigated the prospective associations between ADHD and a wide range of cardiovascular diseases in adults. In a nationwide population‐based cohort study, we identified 5,389,519 adults born between 1941 and 1983, without pre‐existing cardiovascular diseases, from Swedish registers. The study period was from January 1, 2001 to December 31, 2013. Incident cardiovascular disease events were identified according to ICD codes. Hazard ratios (HR) with 95% confidence intervals (CI) were calculated using Cox proportional hazards regression model, with ADHD as a time‐varying exposure. After an average 11.80 years of follow‐up, 38.05% of individuals with ADHD versus 23.57% of those without ADHD had at least one diagnosis of cardiovascular disease (p<0.0001). ADHD was significantly associated with increased risk of any cardiovascular disease (HR=2.05, 95% CI: 1.98‐2.13) after adjusting for sex and year of birth. Further adjustments for education level, birth country, type 2 diabetes mellitus, obesity, dyslipidemia, sleep problems and heavy smoking attenuated the association, which however remained significant (HR=1.84, 95% CI: 1.77‐1.91). Further adjustment for psychiatric comorbidities attenuated but could not fully explain the association (HR=1.65, 95% CI: 1.59‐1.71). The strongest associations were found for cardiac arrest (HR=2.28, 95% CI: 1.81‐2.87), hemorrhagic stroke (HR=2.16, 95% CI: 1.68‐2.77), and peripheral vascular disease/arteriosclerosis (HR=2.05, 95% CI: 1.76‐2.38). Stronger associations were observed in males and younger adults, while comparable associations were found among individuals with or without psychotropic medications and family history of cardiovascular diseases. These data suggest that ADHD is an independent risk factor for a wide range of cardiovascular diseases. They highlight the importance of carefully monitoring cardiovascular health and developing age‐appropriate and individualized strategies to reduce the cardiovascular risk in individuals with ADHD. 相似文献
98.
Daniel Liedtke Isabell Erhard Keiko Abe Makoto Furutani‐Seiki Hisato Kondoh Manfred Schartl 《Pigment cell & melanoma research》2014,27(2):221-233
Chemokine signals mediated by Sdf1/Cxcl12 through the chemokine receptor Cxcr4 are thought to play an instructive role in tumor migration and organ‐specific metastasis. We have used a small aquarium fish model to contribute to a better understanding of how the course of melanoma development is influenced by Sdf1 signals in vivo. We studied oncogene‐induced skin tumor appearance and progression in the transgenic medaka (Oryzias latipes) melanoma model. Similar to humans, invasive medaka melanomas show increased levels of sdf1, cxcr4, and cxcr7 gene expression. Stable transgenic fish lines overexpressing sdf1 exclusively in pigment cells showed a reduction in melanoma appearance and progression. Remarkably, diminished levels of functional Cxcr7, but not of Cxcr4b, resulted in strongly reduced melanoma invasiveness and a repression of melanoma. Our results thereby indicate that Sdf1 signals via Cxcr7 are able to constrain melanoma growth in vivo and that these signals influence tumor outcome. 相似文献
99.
100.
In vivo cervical cancer growth inhibition by genetically engineered cytotoxic T cells 总被引:3,自引:0,他引:3
Dall P Herrmann I Durst B Stoff-Khalili MA Bauerschmitz G Hanstein B Niederacher D 《Cancer immunology, immunotherapy : CII》2005,54(1):51-60
Purpose: The CD44 v7/8 splice variant that is frequently expressed in cervical carcinoma and rarely expressed in normal tissues displays promising properties as a target antigen for cancer immune therapy. In this study, cytotoxic T lymphocytes (CTLs) were genetically engineered to gain CD44v7/8 target specificity. Methods: Clone 96 (CI96), an established murine cytotoxic T-cell line, and naïve murine T cells were retrovirally transduced with a fusion gene construct encoding for the single chain fragment scFv of the monoclonal antibody VFF17 and for the chain of the T-cell receptor (TCR). The therapeutic potential of genetically engineered T cells was tested in vitro and in vivo. Results: Surface expression of the chimeric TCR on infected Cl96 and naïve T cells was shown by FACS analysis. CD44v7/8-positive target cells were efficiently lysed by transduced Cl96 and naïve T cells, demonstrating the functionality and specificity of the chimeric TCR. In a xenograft BALB/c mouse model, efficient growth retardation of CD44v7/8-positive tumours was mediated by genetically engineered Cl96(VFF17)cyYZ cells. Conclusions: We were able to reprogramme the target specificity of recombinant Cl96 and naïve CTLs resulting in efficient cytolysis of CD44v7/8-positive cervical cancer cells. High transduction rates and the specific cytolysis of CD44v7/8-redirected CTLs are promising tools for an immune gene therapy approach for advanced cervical cancer.Abbreviations Ab
Antibody
- CTL
Cytolytic T lymphocyte
- mAb
Monoclonal antibody
- TCR
T-cell receptor 相似文献