Oldest Papers
Cancer susceptibility and reproductive trade-offs: a model of the evolution of cancer defences.
Amy M Boddy, Hanna Kokko, Felix Breden, Gerald S Wilkinson, C Athena Aktipis
Philosophical transactions of the Royal Society of London. Series B, Biological sciences·2015
The factors influencing cancer susceptibility and why it varies across species are major open questions in the field of cancer biology. One underexplored source of variation in cancer susceptibility may arise from trade-offs between reproductive competitiveness (e.g. sexually selected traits, earlier reproduction and higher fertility) and cancer defence. We build a model that contrasts the probabilistic onset of cancer with other, extrinsic causes of mortality and use it to predict that intense reproductive competition will lower cancer defences and increase cancer incidence. We explore the trade-off between cancer defences and intraspecific competition across different extrinsic mortality conditions and different levels of trade-off intensity, and find the largest effect of competition on cancer in species where low extrinsic mortality combines with strong trade-offs. In such species, selection to delay cancer and selection to outcompete conspecifics are both strong, and the latter conflicts with the former. We discuss evidence for the assumed trade-off between reproductive competitiveness and cancer susceptibility. Sexually selected traits such as ornaments or large body size require high levels of cell proliferation and appear to be associated with greater cancer susceptibility. Similar associations exist for female traits such as continuous egg-laying in domestic hens and earlier reproductive maturity. Trade-offs between reproduction and cancer defences may be instantiated by a variety of mechanisms, including higher levels of growth factors and hormones, less efficient cell-cycle control and less DNA repair, or simply a larger number of cell divisions (relevant when reproductive success requires large body size or rapid reproductive cycles). These mechanisms can affect intra- and interspecific variation in cancer susceptibility arising from rapid cell proliferation during reproductive maturation, intrasexual competition and reproduction.
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View paper →Inclusive fitness effects can select for cancer suppression into old age.
Joel S Brown, C Athena Aktipis
Philosophical transactions of the Royal Society of London. Series B, Biological sciences·2015
Natural selection can favour health at youth or middle age (high reproductive value) over health at old age (low reproductive value). This means, all else being equal, selection for cancer suppression should dramatically drop after reproductive age. However, in species with significant parental investment, the capacity to enhance inclusive fitness may increase the reproductive value of older individuals or even those past reproductive age. Variation in parental investment levels could therefore contribute to variation in cancer susceptibility across species. In this article, we describe a simple model and framework for the evolution of cancer suppression with varying levels of parental investment and use this model to make testable predictions about variation in cancer suppression across species. This model can be extended to show that selection for cancer suppression is stronger in species with cooperative breeding systems and intergenerational transfers. We consider three cases that can select for cancer suppression into old age: (i) extended parental care that increases the survivorship of their offspring, (ii) grandparents contributing to higher fecundity of their children and (iii) cooperative breeding where helpers forgo reproduction or even survivorship to assist parents in having higher fecundity.
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View paper →Mechanisms behind the testing effect: an empirical investigation of retrieval practice in meaningful learning
Tino Endres, Alexander Renkl
Frontiers in Psychology·2015·52 citations
No abstract available
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View paper →The neutral metallopeptidase NMP1 of <i>Trichoderma guizhouense</i> is required for mycotrophy and self‐defence
Jian Zhang, Gunseli Bayram Akcapinar, Lea Atanasova, Mohammad Javad Rahimi, Agnieszka Przylucka, Dongqing Yang, Christian P. Kubicek, Ruifu Zhang, Qirong Shen, Irina S. Druzhinina
Environmental Microbiology·2015·57 citations
<jats:title>Summary</jats:title>
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<jats:italic>T</jats:italic>
</jats:styled-content>
<jats:italic>richoderma guizhouense</jats:italic>
<jats:styled-content style="fixed-case">NJAU</jats:styled-content>
4742 (
<jats:italic>Harzianum</jats:italic>
clade) can suppress the causative agent of banana wild disease
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<jats:italic>F</jats:italic>
</jats:styled-content>
<jats:italic>usarium oxysporum</jats:italic>
f. sp.
<jats:italic>cubense</jats:italic>
4 (Foc4). To identify genes involved in this trait, we used
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‐
<jats:styled-content style="fixed-case">DNA</jats:styled-content>
insertional mutagenesis and isolated one mutant that was unable to overgrow Foc4 and had reduced antifungal ability. Using the high‐efficiency thermal asymmetric interlaced‐
<jats:styled-content style="fixed-case">PCR</jats:styled-content>
, the
<jats:styled-content style="fixed-case">T</jats:styled-content>
‐
<jats:styled-content style="fixed-case">DNA</jats:styled-content>
was located in the terminator of a neutral metalloprotease gene (encoding a
<jats:styled-content style="fixed-case">MEROPS</jats:styled-content>
family M35 protease), which was named
<jats:italic>nmp1</jats:italic>
. The antifungal activity of the mutant was recovered by retransformation with wild‐type
<jats:italic>nmp1</jats:italic>
gene. The purified NMP1 (overexpressed in
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<jats:italic>P</jats:italic>
</jats:styled-content>
<jats:italic>ichia pastoris</jats:italic>
) did not inhibit the growth and germination of other fungi
<jats:italic>in vitro</jats:italic>
. Its addition, however, partly recovered the antifungal activity of the mutant strain against some fungi. The expression of
<jats:italic>nmp1</jats:italic>
is induced by the presence of fungi and by dead fungal biomass, but the time‐course of transcript accumulation following the physical contact depends on mode of interaction: it increases in cases of long‐lasting parasitism and decreases if the prey fungus is dead shortly after or even before the contact (predation). We thus conclude that NMP1 protein of
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<jats:italic>T</jats:italic>
</jats:styled-content>
<jats:italic>. guizhouense</jats:italic>
has major importance for mycotrophic interactions and defence against other fungi.
</jats:p>
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View paper →Durand-Ruel: The Art Dealer Who Liked Impressionists Before They Were Cool : NPR
Susan Stamberg
NPR·2015
Parisian art dealer Paul Durand-Ruel acquired some 5,000 impressionist works long before others were buying them. Claude Monet said he and his artist friends "would have died of hunger" without him.
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View paper →Feeling Aware
Jeremy Birnholtz, Darren Gergle, Noah Liebman, Sarah Sinclair
Proceedings of the 17th International Conference on Human-Computer Interaction with Mobile Devices and Services·2015·3 citations
No abstract available
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View paper →Genome Sequence and Annotation of <i>Trichoderma parareesei</i> , the Ancestor of the Cellulase Producer <i>Trichoderma reesei</i>
Dongqing Yang, Kyle Pomraning, Alexey Kopchinskiy, Razieh Karimi Aghcheh, Lea Atanasova, Komal Chenthamara, Scott E. Baker, Ruifu Zhang, Qirong Shen, Michael Freitag, Christian P. Kubicek, Irina S. Druzhinina
Genome Announcements·2015·25 citations
<jats:title>ABSTRACT</jats:title>
<jats:p>
The filamentous fungus
<jats:italic>Trichoderma parareesei</jats:italic>
is the asexually reproducing ancestor of
<jats:italic>Trichoderma reesei</jats:italic>
, the holomorphic industrial producer of cellulase and hemicellulase. Here, we present the genome sequence of the
<jats:italic>T. parareesei</jats:italic>
type strain CBS 125925, which contains genes for 9,318 proteins.
</jats:p>
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View paper →Compulsory Sexuality: Evaluating an Emerging Concept
Kristina Gupta
Signs: Journal of Women in Culture and Society·2015·100 citations
No abstract available
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View paper →The ‘Greenization’ of Chinese Bits: An Empirical Study of the Environmental Provisions in Chinese Bits and its Implications for China’s Future Bit-Making
Manjiao Chi
Journal of International Economic Law·2015·6 citations
Incorporating environmental provisions (EPs) in International investment agreements is an important way for states to confront grave environmental challenges through the discourse of international investment law. An empirical study of the EPs incorporated in all 104 Chinese BITs in force shows that only a limited number of Chinese BITs contain EPs and that the generational and regional distribution of the EPs are imbal- anced. The overall lack and low quality of the EPs make Chinese BITs as a whole in- sufficiently environmentally friendly. This study reveals that Chinese BITs are getting increasingly ‘green’, especially the recent decade. Mere incorporation of EPs in BITs does not necessarily make BITs ‘green’. Whether and to what extent EPs can play a constructive role in environmental protection depends on how they are applied and how the two seemingly conflicting purposes of BITs, i.e. investment protection and en- vironmental protection, are reconciled in international investment arbitration. China has an urgent need to ‘greenize’ its BITs. Toward this end, China should, first, enhance the availability and effectiveness of EPs in its BITs; second, make consorted efforts to incorporate certain EP-related provisions in its BITs and relevant national laws; third, change its current dichotomic BIT-making strategy.
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View paper →Two Concerns about the Medicalization of Love
MARTIN O’REILLY
Cambridge Quarterly of Healthcare Ethics·2015·1 citations
No abstract available
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View paper →An ecological measure of immune-cancer colocalization as a prognostic factor for breast cancer.
Carlo C Maley, Konrad Koelble, Rachael Natrajan, Athena Aktipis, Yinyin Yuan
Breast cancer research : BCR·2015
Abundance of immune cells has been shown to have prognostic and predictive significance in many tumor types. Beyond abundance, the spatial organization of immune cells in relation to cancer cells may also have significant functional and clinical implications. However there is a lack of systematic methods to quantify spatial associations between immune and cancer cells. We applied ecological measures of species interactions to digital pathology images for investigating the spatial associations of immune and cancer cells in breast cancer. We used the Morisita-Horn similarity index, an ecological measure of community structure and predator-prey interactions, to quantify the extent to which cancer cells and immune cells colocalize in whole-tumor histology sections. We related this index to disease-specific survival of 486 women with breast cancer and validated our findings in a set of 516 patients from different hospitals. Colocalization of immune cells with cancer cells was significantly associated with a disease-specific survival benefit for all breast cancers combined. In HER2-positive subtypes, the prognostic value of immune-cancer cell colocalization was highly significant and exceeded those of known clinical variables. Furthermore, colocalization was a significant predictive factor for long-term outcome following chemotherapy and radiotherapy in HER2 and Luminal A subtypes, independent of and stronger than all known clinical variables. Our study demonstrates how ecological methods applied to the tumor microenvironment using routine histology can provide reproducible, quantitative biomarkers for identifying high-risk breast cancer patients. We found that the clinical value of immune-cancer interaction patterns is highly subtype-specific but substantial and independent to known clinicopathologic variables that mostly focused on cancer itself. Our approach can be developed into computer-assisted prediction based on histology samples that are already routinely collected.
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View paper →A Dream Best Forgotten
Theodore T. Bartholomew, Brittany E. Gundel, Neeta Kantamneni
The Counseling Psychologist·2015·14 citations
Refugees are often forced into states of imposed vulnerability in which loss is common and migration is normative. Karen refugees from Myanmar have endured a long civil war with the Burmese government, followed by their forced relocation to refugee camps and subsequent global resettlement. This phenomenological study aimed to understand the meanings ascribed to pre-resettlement stress among resettled Karen refugees. We interviewed six participants who were identified through purposeful sampling in a Karen refugee community. Using phenomenological analysis, we identified and interpreted 286 meaning units. The meaning units were then grouped into four themes: (a) Loss From Oppression, (b) Resignation and Acceptance in a Context of Regular Violence, (c) Ongoing Insecurity While Confined in Camps, and (d) Redefined Selfhood. The results provide a contextual understanding of the pre-resettlement stressors experienced by Karen refugees.
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