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We further tested the effects of these knockout lines on an independent behavioral pupal trait (pupation site choice) and found that a similar fraction had a significant effect as well. Our data thus confirm the implication that a large number of genes can influence independent quantitative traits.As writing systems are a relatively novel invention (slightly over 5 kya),1 they could not have influenced the evolution of our species. Instead, reading might recycle evolutionary older mechanisms that originally supported other tasks2,3 and preceded the emergence of written language. Accordingly, it has been shown that baboons and pigeons can be trained to distinguish words from nonwords based on orthographic regularities in letter co-occurrence.4,5 This suggests that part of what is usually considered reading-specific processing could be performed by domain-general visual mechanisms. Here, we tested this hypothesis in humans if the reading system relies on domain-general visual mechanisms, some of the effects that are often found with orthographic material should also be observable with non-orthographic visual stimuli. We performed three experiments using the same exact design but with visual stimuli that progressively departed from orthographic material. Subjects were passively familiarized with a set of composite visual items and tested in an oddball paradigm for their ability to detect novel stimuli. Participants showed robust sensitivity to the co-occurrence of features ("bigram" coding) with strings of letter-like symbols but also with made-up 3D objects and sinusoidal gratings. This suggests that the processing mechanisms involved in the visual recognition of novel words also support the recognition of other novel visual objects. These mechanisms would allow the visual system to capture statistical regularities in the visual environment.6-9 We hope that this work will inspire models of reading that, although addressing its unique aspects, place it within the broader context of vision.The insect sex determination and the intimately linked dosage compensation pathways represent a challenging evolutionary puzzle that has been solved only in Drosophila melanogaster. Analyses of orthologs of the Drosophila genes identified in non-drosophilid taxa1,2 revealed that evolution of sex determination pathways is consistent with a bottom-up mode,3 where only the terminal genes within the pathway are well conserved. doublesex (dsx), occupying a bottom-most position and encoding sex-specific proteins orchestrating downstream sexual differentiation processes, is an ancient sex-determining gene present in all studied species.2,4,5 With the exception of lepidopterans, its female-specific splicing is known to be regulated by transformer (tra) and its co-factor transformer-2 (tra2).6-20 Here we show that in the African malaria mosquito Anopheles gambiae, a gene, which likely arose in the Anopheles lineage and which we call femaleless (fle), controls sex determination in females by regulating splicing of dsx and fruitless (fru; another terminal gene within a branch of the sex determination pathway). Moreover, fle represents a novel molecular link between the sex determination and dosage compensation pathways. It is necessary to suppress activation of dosage compensation in females, as demonstrated by the significant upregulation of the female X chromosome genes and a correlated female-specific lethality, but no negative effect on males, in response to fle knockdown. This unexpected property, combined with a high level of conservation in sequence and function in anopheline mosquitoes, makes fle an excellent target for genetic control of all major vectors of human malaria.The role of sacubitril and/or valsartan in patient with heart failure (HF) is established. Whether sacubitril and/or valsartan plays a role in improving outcomes in patients after ST-segment elevation myocardial infarction (STEMI) is unknown. see more The current study aims to comparing the efficacy and safety of sacubitril and/or valsartan versus ramipril in post-STEMI patients. Patients presenting with STEMI were randomized to receive either sacubitril and/or valsartan or ramipril after primary percutaneous coronary intervention. The main efficacy endpoint was major adverse cardiac events (MACE) at 30 days and 6 months, defined as a composite of cardiac death, myocardial infarction, and HF hospitalizations. Multiple secondary clinical safety and efficacy endpoints were examined. A total of 200 patients were randomized from January 2018 to March 2019, mean age 54.5±10.4, 87% men, 75% presented with anterior wall STEMI. Baseline clinical and echocardiographic characteristics were comparable between groups. The primary endpoint of MACE was similar with sacubitril/valsartan versus ramipril at 30 days (p = 0.18); however, at 6 months, sacubitril/valsartan was associated with significant reduction of MACE (p = 0.005), mainly driven by reduction in HF hospitalizations (18% vs 36%, OR 0.40, 95% 0.22 to 0.75; p = 0.004). At 6 months, LV ejection fraction was higher with sacubitril/valsartan (46.8±12.5% vs 42.09±13.8%; p = 0.012), with improved LV remodelling (LV end diastolic dimension 50.6±3.9 mm vs 53.2±2.7 mm, p = 0.047; and LV end systolic dimension 36.1±3.4 mm versus 39.9±6.3 mm, p = 0.001) compared with ramipril. No difference in other efficacy or safety clinical endpoints was observed. In conclusion, early initiation of sacubitril/valsartan may offer clinical benefit and improvement in myocardial remodelling in post-STEMI patients.Cardiogenic shock (CS) is associated with high mortality and often requires involvement of a multidisciplinary provider team to deliver timely care. Care coordination is more difficult on weekends, which may lead to a delay in care. We sought to assess the effect of weekend admissions on outcomes in patients admitted with CS. Patients admitted with CS were identified from 2005 to 2014 in the National Inpatient Sample using ICD9 code 785.51. Baseline demographics, in-hospital procedures, and outcomes were obtained and compared by day of admission. A multivariable model was used to assess the impact of weekend admission on in-hospital mortality. A total of 875,054 CS admissions were identified (age 67.4 ± 15.1 years, 40.2% female, 72.1% Caucasian), with 23% of patients being admitted on weekends. Baseline co-morbidities were similar between groups. Weekend admissions were associated with higher in-hospital mortality (40.6% vs 37.5%) and cardiac arrest (20.3% vs 18.1%, p less then 0.001 for both) consistently over the study period. Use of temporary and permanent mechanical support devices and heart transplantation were slightly less common for weekend admissions. In a multivariable model adjusting for relevant confounders, weekend admission was associated with a 10% increased mortality in patients with CS. In conclusion, patients with CS admitted on weekends had higher in-hospital mortality and were slightly less likely to receive mechanical support and advanced therapies compared with those admitted on weekdays. Future studies and health system initiatives should focus on rectifying these disparities with around-the-clock multidisciplinary coordinated care for CS.Fanconi anemia (FA) is an inherited syndrome of bone marrow failure (BMF) due to disrupted DNA repair. In this issue of Cell Stem Cell, Rodríguez et al. (2021) show that blood stem cells from FA patients have abnormal and inflammation-induced MYC expression, which promotes their proliferation in the face of increasing DNA damage.The regeneration potential of axons projecting from retinal ganglion cells (RGCs) is lost shortly after birth. In Nature, Lu et al. (2020) demonstrate that epigenetic reprogramming of RGCs by overexpression of Oct4, Sox2, and Klf4 leads to axon regeneration and restoration of vision in a glaucoma model and aged mice.Human hematopoietic stem cells (HSCs) exhibit attrition of their self-renewal capacity when cultured ex vivo, a process that is partially reversed upon treatment with epigenetic modifiers, most notably inhibitors of histone deacetylases (HDACs) or lysine-specific demethylase LSD1. A recent study showed that the human HSC self-renewal agonist UM171 modulates the CoREST complex, leading to LSD1 degradation, whose inhibition mimics the activity of UM171. The mechanism underlying the UM171-mediated loss of CoREST function remains undetermined. We now report that UM171 potentiates the activity of a CULLIN3-E3 ubiquitin ligase (CRL3) complex whose target specificity is dictated by the poorly characterized Kelch/BTB domain protein KBTBD4. CRL3KBTBD4 targets components of the LSD1/RCOR1 corepressor complex for proteasomal degradation, hence re-establishing H3K4me2 and H3K27ac epigenetic marks, which are rapidly decreased upon ex vivo culture of human HSCs.Blastocyst complementation represents a powerful technique for interspecies organogenesis but is limited by low chimerism due to developmental incompatibilities. In this issue of Cell Stem Cell,Nishimura et al. (2021) circumvent early developmental barriers by disabling Igf1r in host embryos, conferring donor cells with a growth advantage from mid-gestation onward.Computational biology is enabling an explosive growth in our understanding of stem cells and our ability to use them for disease modeling, regenerative medicine, and drug discovery. We discuss four topics that exemplify applications of computation to stem cell biology cell typing, lineage tracing, trajectory inference, and regulatory networks. We use these examples to articulate principles that have guided computational biology broadly and call for renewed attention to these principles as computation becomes increasingly important in stem cell biology. We also discuss important challenges for this field with the hope that it will inspire more to join this exciting area.COVID-19 has unfortunately halted lab work, conferences, and in-person networking, which is especially detrimental to researchers just starting their labs. Through social media and our reviewer networks, we met some early-career stem cell investigators impacted by the closures. Here, they introduce themselves and their research to our readers.Direct cell fate conversion of human somatic cells into induced neurons (iNs) is often regarded as a highly concerted one-step process. In this issue of Cell Stem Cell, Cates et al. (2021) dissect the iN conversion trajectory into two largely independent steps and identify key players at each stage.2021 marks the 30th anniversary of the revelation that cyclosporin A and FK506 act in a way previously not seen-as "molecular glues" that induce neo-protein-protein associations. As a torrent of new molecular-glue probes and medicines are fueling interest in this field, I explore the arc of this story.Hardwired circuits encoding innate responses have emerged as an essential feature of the mammalian brain. Sweet and bitter evoke opposing predetermined behaviors. Sweet drives appetitive responses and consumption of energy-rich food sources, whereas bitter prevents ingestion of toxic chemicals. Here we identified and characterized the neurons in the brainstem that transmit sweet and bitter signals from the tongue to the cortex. Next we examined how the brain modulates this hardwired circuit to control taste behaviors. We dissect the basis for bitter-evoked suppression of sweet taste and show that the taste cortex and amygdala exert strong positive and negative feedback onto incoming bitter and sweet signals in the brainstem. Finally we demonstrate that blocking the feedback markedly alters responses to ethologically relevant taste stimuli. These results illustrate how hardwired circuits can be finely regulated by top-down control and reveal the neural basis of an indispensable behavioral response for all animals.

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