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The Darkside War
\"There are many aliens out there. They come in all sorts of shapes and sizes. You will probably fight [beside] creatures that will haunt your nightmares long after you leave the service, and they're the good guys. However, if you want to survive your first encounter with the enemy there are five aliens that you need to learn to spot on sight. Pay attention now and you might live to see your mama again someday\"-- Provided by publisher.
Book
Wicked evolution: Can we address the sociobiological dilemma of pesticide resistance?
Resistance to insecticides and herbicides has cost billions of U.S. dollars in the agricultural sector and could result in millions of lives lost to insect-vectored diseases. We mostly continue to use pesticides as if resistance is a temporary issue that will be addressed by commercialization of new pesticides with novel modes of action. However, current evidence suggests that insect and weed evolution may outstrip our ability to replace outmoded chemicals and other control mechanisms. To avoid this outcome, we must address the mix of ecological, genetic, economic, and sociopolitical factors that prevent implementation of sustainable pest management practices. We offer an ambitious proposition.
Journal Article
Ethnographic collecting and African agency in early colonial West Africa : a study of trans-imperial cultural flows
\"The early collections from Africa in Liverpool's World Museum reflect the city's longstanding shipping and commercial links with Africa's Atlantic coast. A principal component of these collections is an assemblage of several thousand artefacts from western Africa that were transported to institutions in northwest England between 1894 and 1916 by the Liverpool steam ship engineer Arnold Ridyard. While Ridyard's collecting efforts can be seen to have been shaped by the steamers' dynamic capacity to connect widely separated people and places, his Methodist credentials were fundamental in determining the profile of his African networks, because they meant that he was not part of official colonial authority in West Africa. Kingdon's study uncovers the identities of many of Ridyard's numerous West African collaborators and discusses their interests and predicaments under the colonial dispensation. Against this background account, their agendas are examined with reference to surviving narratives that accompanied their donations and within the context of broader processes of trans-imperial exchange, through which they forged new identities and statuses for themselves and attempted to counter expressions of British cultural imperialism in the region. The study concludes with a discussion of the competing meanings assigned to the Ridyard assemblage by the Liverpool Museum and examines the ways in which its re-contextualization in museum contexts helped to efface signs of the energies and narratives behind its creation.\"--Publisher's website.
Book
Mouse models of hepatocellular carcinoma: an overview and highlights for immunotherapy research
Mouse models are the basis of preclinical and translational research in hepatocellular carcinoma (HCC). Multiple methods exist to induce tumour formation in mice, including genetically engineered mouse models, chemotoxic agents, intrahepatic or intrasplenic injection of tumour cells and xenograft approaches. Additionally, as HCC generally develops in the context of diseased liver, methods exist to induce liver disease in mice to mimic viral hepatitis, fatty liver disease, fibrosis, alcohol-induced liver disease and cholestasis. Similar to HCC in humans, response to therapy in mouse models is monitored with imaging modalities such as CT or MRI, as well as additional techniques involving bioluminescence. As immunotherapy is increasingly applied to HCC, mouse models for these approaches are required for preclinical data. In studying cancer immunotherapy, it is important to consider aspects of antitumour immune responses and to produce a model that mimics the complexity of the immune system. This Review provides an overview of the different mouse models of HCC, presenting techniques to prepare an HCC mouse model and discussing different approaches to help researchers choose an appropriate model for a specific hypothesis. Specific aspects of immunotherapy research in HCC and the applied mouse models in this field are also highlighted.
Journal Article
Molecular analysis of PRC2 recruitment to DNA in chromatin and its inhibition by RNA
Biochemical reconstitution of PRC2 interactions with chromatinized templates demonstrates that protein-free linker DNA dominates the PRC2-nucleosome interaction, while RNA inhibits binding.
Many studies have revealed pathways of epigenetic gene silencing by Polycomb repressive complex 2 (PRC2)
in vivo
, but understanding the underlying molecular mechanisms requires biochemistry. Here we analyze interactions of reconstituted human PRC2 with nucleosome complexes. Histone modifications, the H3K27M cancer mutation, and inclusion of JARID2 or EZH1 in the PRC2 complex have unexpectedly minor effects on PRC2–nucleosome binding. Instead, protein-free linker DNA dominates the PRC2–nucleosome interaction. Specificity for CG-rich sequences is consistent with PRC2 occupying CG-rich DNA
in vivo
. PRC2 preferentially binds methylated DNA regulated by its AEBP2 subunit, suggesting how DNA and histone methylation collaborate to repress chromatin. We find that RNA, known to inhibit PRC2 activity, is not a methyltransferase inhibitor
per se
. Instead, RNA sequesters PRC2 from nucleosome substrates, because PRC2 binding requires linker DNA, and RNA and DNA binding are mutually exclusive. Together, we provide a model for PRC2 recruitment and an explanation for how actively transcribed genomic regions bind PRC2 but escape silencing.
Journal Article
Mycorrhizal type determines the magnitude and direction of root‐induced changes in decomposition in a temperate forest
Although it is increasingly being recognized that roots play a key role in soil carbon (C) dynamics, the magnitude and direction of these effects are unknown. Roots can accelerate soil C losses by provisioning microbes with energy to decompose organic matter or impede soil C losses by enhancing microbial competition for nutrients. We experimentally reduced belowground C supply to soils via tree girdling, and contrasted responses in control and girdled plots for three consecutive growing seasons. We hypothesized that decreases in belowground C supply would have stronger effects in plots dominated by ectomycorrhizal (ECM) trees rather than arbuscular mycorrhizal (AM) trees. In ECM‐dominated plots, girdling decreased the activity of enzymes that break down soil organic matter (SOM) by c. 40%, indicating that, in control plots, C supply from ECM roots primes microbial decomposition. In AM‐dominated plots, girdling had little effect on SOM‐degrading enzymes, but increased the decomposition of AM leaf litter by c. 43%, suggesting that, in control plots, AM roots may intensify microbial competition for nutrients. Our findings indicate that root‐induced changes in soil processes depend on forest composition, and that shifts in the distribution of AM and ECM trees owing to climate change may determine soil C gains and losses.
Journal Article
Voluntary Programs to Encourage Refuges for Pesticide Resistance Management: Lessons from a Quasi-Experiment
Economists often treat pesticide resistance as a common-pool resource problem. While pecuniary economic incentives are the standard prescription for open-access market failures arising from such resources, non-pecuniary behavioral approaches (e.g., \"nudges\") are also effective in some cases. Yet non-pecuniary instruments have not previously been evaluated for managing pesticide resistance. I empirically evaluate the performance of such an intervention to manage pest resistance to genetically engineered Bacillus thuringiensis (Bt) corn. The U.S. Environmental Protection Agency permits sale of Bt seed conditional on seed producers compelling customers to plant mandated levels of non-Bt refuge to delay the evolution of Bt resistance. Because of compliance challenges, the Bt seed producer Monsanto piloted a social marketing program to promote refuge in 17 North Carolina counties in 2013-2014. Using 2013-2016 sales data, I use difference-in-differences, fractional regression, discrete changes-in-changes, and matched differences econometric models to identify the average treatment effect of the program on refuge planting. Results suggest that if it had covered all corn growers in North Carolina, the intervention would have led the average grower to plant between 2.6% (preferred estimate) and 5.8% more refuge in 2014 compared to the counterfactual. The program increased by at least 12% the average probability of planting any refuge in 2014. I find little evidence that effects of the program persisted in subsequent years after cessation, nor that the program increased compliance with mandated refuge thresholds. Informed by behavioral economics research on other environmental and resource policies, I discuss the implications of these findings for pesticide resistance management.
Journal Article
A Comprehensive Review of Hepatic Hemangioma Management
Background
Hepatic hemangiomas (HHs) are benign liver lesions often discovered incidentally on imaging for various unrelated pathologies. We herein review the etiology, classification, diagnostic imaging, and management of HHs.
Methods
A comprehensive systematic review was performed utilizing MEDLINE/PubMed and Web of Science databases, with the end of search date being March 1, 2022, regarding HH diagnosis, imaging, and management.
Results
HHs can be broadly classified as capillary hemangiomas or cavernous hemangiomas. While the exact pathophysiology related to the development of HHs remains largely unknown, hormone exposure has been postulated to cause HH growth. HHs appear homogenously hyperechoic on US with distinct margins and posterior acoustic enhancement. While cavernous hemangiomas appear as well-defined hypodense lesions on pre-contrast CT images with the same density as the vasculature, one of the most reliable imaging features for diagnosing cavernous hemangiomas is high signal intensity on T2 weighted images. While most HHs are asymptomatic, some patients can present with pain or compressive symptoms with bleeding/rupture being very rare. Kasabach-Merritt syndrome is a rare but life-threatening condition associated with thrombocytopenia and microangiopathic hemolytic anemia. When HHs are symptomatic or in the setting of Kasabach Merritt syndrome, surgery is indicated. Enucleation is an attractive surgical option for HH as it spares normal liver tissue. Most patients experience symptom relief following surgical resection.
Conclusion
HHs are very common benign liver lesions. High-quality imaging is imperative to distinguish HHs from other liver lesions. Surgery is generally reserved for patients who present with symptoms such as pain, obstruction, or rarely Kasabach-Merritt syndrome. Surgery can involve either formal resection or, in most instances, simple enucleation. Patients generally have good outcomes following surgery with resolution of their symptoms.
Journal Article
Saccadic eye movements evoked by optogenetic activation of primate V1
Optogenetic manipulations of behavior in primates have largely been unsuccessful. Here, the authors report that monkeys reliably shift their gaze toward the receptive field of optically driven channelrhodopsin-2–expressing V1 neurons.
Optogenetics has advanced our understanding of the neural basis of simple behaviors in rodents and small animals. In primates, however, for which more sophisticated behavioral assays exist, optogenetic manipulations of behavior have been unsuccessful. We found that monkeys reliably shifted their gaze toward the receptive field of optically driven channelrhodopsin-2–expressing neurons of the primary visual cortex. This result establishes optogenetics as a viable tool for the causal analysis of behavior in primate brain.
Journal Article
Thermal stress induces glycolytic beige fat formation via a myogenic state
Environmental cues profoundly affect cellular plasticity in multicellular organisms. For instance, exercise promotes a glycolytic-to-oxidative fibre-type switch in skeletal muscle, and cold acclimation induces beige adipocyte biogenesis in adipose tissue. However, the molecular mechanisms by which physiological or pathological cues evoke developmental plasticity remain incompletely understood. Here we report a type of beige adipocyte that has a critical role in chronic cold adaptation in the absence of β-adrenergic receptor signalling. This beige fat is distinct from conventional beige fat with respect to developmental origin and regulation, and displays enhanced glucose oxidation. We therefore refer to it as glycolytic beige fat. Mechanistically, we identify GA-binding protein α as a regulator of glycolytic beige adipocyte differentiation through a myogenic intermediate. Our study reveals a non-canonical adaptive mechanism by which thermal stress induces progenitor cell plasticity and recruits a distinct form of thermogenic cell that is required for energy homeostasis and survival.
The mouse develops a developmentally and functionally distinct, non-canonical beige fat cell type as an adaptation to cold ambient temperature.
Journal Article