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In case-control single-cell RNA-seq studies, sample-level labels are transferred onto individual cells, labeling all case cells as affected, but only a small fraction of them may actually be perturbed. Here, using simulations, we demonstrate that the standard approach to single cell analysis fails to isolate the subset of affected case cells and their markers when either the affected subset is small, or when the strength of the perturbation is mild. To address this fundamental limitation, we introduce HiDDEN, a computational method that refines the case-control labels to accurately reflect the perturbation status of each cell. We show HiDDEN’s superior ability to recover biological signals missed by the standard analysis workflow in simulated ground truth datasets of cell type mixtures. When applied to a dataset of human multiple myeloma precursor conditions, HiDDEN recapitulates the expert manual annotation and discovers malignancy in previously considered healthy early stage samples. When applied to a mouse model of demyelination, HiDDEN identifies an endothelial subpopulation playing a role in early stage blood-brain barrier dysfunction. We anticipate that HiDDEN should find a wide usage in contexts which require the detection of subtle changes in cell types across conditions.

Microglia have emerged as key players in the pathogenesis of neurodegenerative conditions such as Alzheimer’s disease (AD). In response to CNS stimuli, these cells adopt distinct transcriptional and functional subtypes known as states. However, an understanding of the function of these states has been elusive, especially in human microglia, due to lack of tools to model and manipulate this cell-type. Here, we provide a platform for modeling human microglia transcriptional states in vitro. Using single-cell RNA sequencing, we found that exposure of human stem-cell differentiated microglia (iMGLs) to brain-related challenges generated extensive transcriptional diversity which mapped to gene signatures identified in human brain microglia. We identified two in vitro transcriptional clusters that were analogous to human and mouse disease-associated microglia (DAMs), a state enriched in neurodegenerative disease contexts. To facilitate scalable functional analyses, we established a lentiviral approach enabling broad and highly efficient genetic transduction of microglia in vitro. Using this new technology, we demonstrated that MITF (Melanocyte Inducing Transcription Factor), an AD-enriched transcription factor in microglia, drives both a disease-associated transcriptional signature and a highly phagocytic state. Finally, we confirmed these results across iMGLs differentiated from multiple iPSC lines demonstrating the broad utility of this platform. Together, these tools provide a comprehensive resource that enables the manipulation and functional interrogation of human microglial states in both homeostatic and disease-relevant contexts.

Louis Joblot published one of the first manuals of microscopy in 1718, just a few years before both he and Leeuwenhoek died. It contained Joblot's microscope designs and his extensive observations on microorganisms including experiments on spontaneous generation. Joblot's work and his observations have often been overlooked, misdated, and denigrated. This is due to attention given to a few apparently fanciful drawings of microorganisms, and the identification of his work as appearing in a posthumous 1754 edition. The second edition not only placed Joblot's work as decades after Leeuwenhoek's death, but was also expanded by the publisher to include unattributed material from famous sources. Here an attempt is made to shine a light on Joblot's work and bring it out of Leeuwenhoek's shadow.

Aggressive social interactions are used to compete for limited resources and are regulated by complex sensory cues and the organism’s internal state. While both sexes exhibit aggression, its neuronal underpinnings are understudied in females. Here, we identify a population of sexually dimorphic aIPg neurons in the adultDrosophila melanogastercentral brain whose optogenetic activation increased, and genetic inactivation reduced, female aggression. Analysis of GAL4 lines identified in an unbiased screen for increased female chasing behavior revealed the involvement of another sexually dimorphic neuron, pC1d, and implicated aIPg and pC1d neurons as core nodes regulating female aggression. Connectomic analysis demonstrated that aIPg neurons and pC1d are interconnected and suggest that aIPg neurons may exert part of their effect by gating the flow of visual information to descending neurons. Our work reveals important regulatory components of the neuronal circuitry that underlies female aggressive social interactions and provides tools for their manipulation.

Aggressive social interactions are used to compete for limited resources and are regulated by complex sensory cues and the organism’s internal state. While both sexes exhibit aggression, its neuronal underpinnings are understudied in females. Here, we describe a set of connected neurons in the adultDrosophila melanogastercentral brain that drive female aggression. We identified a population of sexually dimorphic aIPg neurons whose optogenetic activation increased, and genetic inactivation reduced, female aggression. Analysis of GAL4 lines identified in an unbiased screen for increased female chasing behavior revealed the involvement of another sexually dimorphic neuron, pC1d, and implicated pC1d and aIPg neurons as core nodes regulating female aggression. pC1d activation increased female aggression and electron microscopy (EM) connectomic analysis demonstrated that aIPg neurons and pC1d have strong reciprocal connections. Our work reveals important regulatory components of the neuronal circuitry that underlies female aggressive social interactions and provides tools for their manipulation.

Key Points Question How do common tools using points-based risk scores compare for identifying high-risk hospitalized inpatients with and without infection? Findings In this cohort study of 5 commonly used point-based risk scores for 1.5 million hospitalizations across 2 US states, the National Early Warning Score had the highest discrimination for identifying inpatients at risk for death and/or intensive care unit transfer. Compared with other tools calculating risk scores, the National Early Warning Score was also more efficient at all sensitivity thresholds. Meaning These results suggest that, among common points-based scoring systems, using the National Early Warning Score for inpatient risk stratification could identify patients with and without infection at high risk of mortality., Importance Risk scores used in early warning systems exist for general inpatients and patients with suspected infection outside the intensive care unit (ICU), but their relative performance is incompletely characterized. Objective To compare the performance of tools used to determine points-based risk scores among all hospitalized patients, including those with and without suspected infection, for identifying those at risk for death and/or ICU transfer. Design, Setting, and Participants In a cohort design, a retrospective analysis of prospectively collected data was conducted in 21 California and 7 Illinois hospitals between 2006 and 2018 among adult inpatients outside the ICU using points-based scores from 5 commonly used tools: National Early Warning Score (NEWS), Modified Early Warning Score (MEWS), Between the Flags (BTF), Quick Sequential Sepsis-Related Organ Failure Assessment (qSOFA), and Systemic Inflammatory Response Syndrome (SIRS). Data analysis was conducted from February 2019 to January 2020. Main Outcomes and Measures Risk model discrimination was assessed in each state for predicting in-hospital mortality and the combined outcome of ICU transfer or mortality with area under the receiver operating characteristic curves (AUCs). Stratified analyses were also conducted based on suspected infection. Results The study included 773 477 hospitalized patients in California (mean [SD] age, 65.1 [17.6] years; 416 605 women [53.9%]) and 713 786 hospitalized patients in Illinois (mean [SD] age, 61.3 [19.9] years; 384 830 women [53.9%]). The NEWS exhibited the highest discrimination for mortality (AUC, 0.87; 95% CI, 0.87-0.87 in California vs AUC, 0.86; 95% CI, 0.85-0.86 in Illinois), followed by the MEWS (AUC, 0.83; 95% CI, 0.83-0.84 in California vs AUC, 0.84; 95% CI, 0.84-0.85 in Illinois), qSOFA (AUC, 0.78; 95% CI, 0.78-0.79 in California vs AUC, 0.78; 95% CI, 0.77-0.78 in Illinois), SIRS (AUC, 0.76; 95% CI, 0.76-0.76 in California vs AUC, 0.76; 95% CI, 0.75-0.76 in Illinois), and BTF (AUC, 0.73; 95% CI, 0.73-0.73 in California vs AUC, 0.74; 95% CI, 0.73-0.74 in Illinois). At specific decision thresholds, the NEWS outperformed the SIRS and qSOFA at all 28 hospitals either by reducing the percentage of at-risk patients who need to be screened by 5% to 20% or increasing the percentage of adverse outcomes identified by 3% to 25%. Conclusions and Relevance In all hospitalized patients evaluated in this study, including those meeting criteria for suspected infection, the NEWS appeared to display the highest discrimination. Our results suggest that, among commonly used points-based scoring systems, determining the NEWS for inpatient risk stratification could identify patients with and without infection at high risk of mortality., This cohort study examines 5 scoring systems used to estimate the risk of clinical deterioration in hospitalized patients with and without suspected infection.

International audience; Louis Bosc (1759-1828) was a naturalist, one of the very first "Linneans" of France, and among the founders of the first Lin-nean Society, the Société Linnéenne de Paris. The early part of his career as a naturalist coincided with the Revolutionary Period in France (1789-1799). During that chaotic period, he published over 30 articles with many species descriptions, 18 of which are currently recognized as valid. Here his complicated life, professional and per-sonal, during the chaotic period of the French Revolution is des-cribed.; Louis Bosc (1759-1828) était un naturaliste, un des pre-miers Linnéens de France et compte parmi les fondateurs de la pre-mière société linnéenne, la Société Linnéenne de Paris. Les débuts de sa carrière de naturaliste ont coïncidé avec la Période Révolution-naire (1789-1799). Durant cette période, il a publié une trentaine d'articles et décrit un grand nombre d'espèces dont 18 sont aujour-d'hui considérées comme valides. Sa vie compliquée à la fois sur le plan professionnel et personnel, pendant la période chaotique de la Révolution Française, est ici décrite

To profile and compare the seating and powered characteristics and functions of electrically powered wheelchairs (EPWs) in a general user population including equipment costs.Case notes of adult EPW users of a regional NHS service were reviewed retrospectively. Seating equipment complexity and type were categorized using the Edinburgh classification. Powered characteristics and functions, including control device type, were recorded.482 cases were included; 53.9% female; mean duration EPW use 8.1 years (SD 7.4); rear wheel drive 88.0%; hand joystick 94.8%. Seating complexity: low 73.2%, medium 18.0%, high 8.7%. Most prevalent diagnoses: multiple sclerosis (MS) 25.3%, cerebral palsy (CP) 18.7%, muscular dystrophy (8.5%). Compared to CP users, MS users were significantly older at first use, less experienced, more likely to have mid-wheel drive and less complex seating. Additional costs for muscular dystrophy and spinal cord injury users were 3-4 times stroke users.This is the first large study of a general EPW user population using a seating classification. Significant differences were found between diagnostic groups; nevertheless, there was also high diversity within each group. The differences in provision and the equipment costs across diagnostic groups can be used to improve service planning. Implications for Rehabilitation At a service planning level, knowledge of a population's diagnostic group and age distribution can be used to inform decisions about the number of required EPWs and equipment costs. At a user level, purchasing decisions about powered characteristics and functions of EPWs and specialised seating equipment need to be taken on a case by case basis because of the diversity of users' needs within diagnostic groups. The additional equipment costs for SCI and MD users are several times those of stroke users and add between 60 and 70% of the cost of basic provision.

Animals exhibit innate behaviours to a variety of sensory stimuli including olfactory cues. In Drosophila, one higher olfactory centre, the lateral horn (LH), is implicated in innate behaviour. However, our structural and functional understanding of the LH is scant, in large part due to a lack of sparse neurogenetic tools for this region. We generate a collection of split-GAL4 driver lines providing genetic access to 82 LH cell types. We use these to create an anatomical and neurotransmitter map of the LH and link this to EM connectomics data. We find ~30% of LH projections converge with outputs from the mushroom body, site of olfactory learning and memory. Using optogenetic activation, we identify LH cell types that drive changes in valence behavior or specific locomotor programs. In summary, we have generated a resource for manipulating and mapping LH neurons, providing new insights into the circuit basis of innate and learned olfactory behavior.

Copyright © 2019, Wolters Kluwer Health. Ophthalmic Communications Society, Inc., Purpose: To study radial peripapillary capillary (RPC) density in the early stages of diabetic retinopathy (DR), using optical coherence tomography angiography. Methods: A cross-sectional evaluation of RPCs was performed using optical coherence tomography angiography (Avanti RTVue-XR 100, Optovue Inc, Fremont, CA). Annular RPC density was the primary outcome. Global density and retinal nerve fiber layer thickness were secondary outcomes. Diabetic eyes were divided into three groups: no DR, mild nonproliferative DR (mild NPDR), and moderate NPDR. Multilevel mixed-effects univariate and multivariate linear regression models were used. Results: We included 155 eyes (n = 42 control; n = 27 no DR; n = 28 mild NPDR; and n = 58 moderate NPDR) from 86 subjects (mean [SD] age 63.39 [10.70] years; 46.45% male). When compared with controls, a significant decrease in annular RPC density was found in all groups of diabetic eyes on multivariate analysis (no DR: β = -2.95, P < 0.001; mild NPDR: β = -1.76, P = 0.017; and moderate NPDR: β = -2.82, P < 0.001). We also detected a significant decrease in retinal nerve fiber layer thickness in diabetic eyes (even in the no DR group). Furthermore, in diabetic eyes, annular RPC density and retinal nerve fiber layer thickness correlated significantly (R = 0.4874, P < 0.001). Conclusion: Peripapillary neurovascular changes occur early in the course of DR. Their significance in the progression of DR warrants further research.

Key points Ultrasonography offers significant advantages in the practice of regional anaesthesia, including faster sensory onset and improved success rates compared with landmark-based techniques.1 Adequate visualization of neural and surrounding structures together with monitoring the spread of local anaesthetic (LA) are absolute prerequisites for the safe and successful practice of ultrasound-guided regional anaesthesia (USGRA). The creation of an ultrasound (US) image is based on the physical properties of the US beam formation, propagation of sound in matter, interaction of sound with reflective interfaces, echo detection, and machine processing. However, there are often a number of significant challenges to acquiring the optimal US images necessary to achieve successful nerve blocks. Such challenges include the acquisition and interpretation of optimal US images of the target structure and needle while avoiding tissue and needle artifacts. Other difficulties may include physiological, pathological, and anatomical factors attributable to the patient and which may affect image quality and interpretation. This article will describe some of these problems, discuss strategies to avoid them, and highlight current and future advances which may assist the practice of USGRA. The spatial resolution of any imaging system is defined as its ability to distinguish two points as separate entities in space. Spatial resolution is commonly subcategorized into axial and lateral resolution.2 Axial resolution is defined as the US machine's ability to differentiate two objects located at different …

Evolution has shaped nervous systems to produce stereotyped behavioural responses to ethologically relevant stimuli. For example when laying eggs, female Drosophila avoid geosmin, an odorant produced by toxic moulds. Here we identify second, third, and fourth order neurons required for this innate olfactory aversion. Connectomics data place these neurons in a complete synaptic circuit from sensory input to descending output. We find multiple levels of valence-specific convergence, including a novel form of axo-axonic input onto second order neurons conveying another danger signal, the pheromone of parasitoid wasps. However, we also observe extensive divergence: second order geosmin neurons connect with a diverse array of 80 third order cell types. We find a pattern of convergence of aversive odour channels at this level. Crossing one more synaptic layer, we identified descending neurons critical for egg-laying aversion. Our data suggest a transition from a labelled line organisation in the periphery to a highly distributed central brain representation that is then coupled to distinct descending pathways.

Introduction The career of Peter Brophy spans some of the most interesting decades in the history of public libraries. Peter himself has been an advocate of change and innovation and a keen observer of what is and is not working. In his early career the emergence of new librarians wanting a library to be an active participant in community life met with a mixture of enthusiasm and apprehension. The spirit of community librarianship emerges in the first decade of the 21st century as a mix of user-oriented provision, partnership working, devolution and community engagement with a performance focus on impact beyond outputs. The library evolves to meet a challenge Under sometimes negative pressure the library changes slowly to meet new needs. The negative pressure is the easily voiced fear that the library has become outdated by social change, rendered redundant by new communications technologies; or it is the financial pressure of the parent institution: school, college, university or local authority. With the best motivation the library changes also in response to a community expectation, perceived or stated, or to an anticipated need or aspiration. Increasingly it is not passive but proactive but this is a requirement of a service that is interventionist not reactive, that originates rather than supports initiative, and that leads rather than waits. Conventionally, the library is a resource that underpins initiative. Collections, information, space to read and study, staff assistance form the main elements of library provision. Ranganathan's five laws of library science (Ranganathan, 1931) are about the collection, organization and delivery of resources to inform and support an initiative, a learning venture or research: Books are for use. Every reader his or her book. Every book its reader. Save the time of the reader. The library is a growing organism. Underpinning the five laws is a sense of philanthropy, an espousal of liberty and freedom of thought and an inherent desire to support the learner that is not immediately evident. Essentially the five laws determine the critical criteria that make an efficient and effective library. Ranganathan's five laws have proved to be so powerful that they have spawned generations of variations and extrapolations translating them into new sets of principles to meet different settings and periods. For example see Application of Ranganathan's Law to the Web Webology (www.webology.ir/2004/v1n2/a8.html#18).

Most sensory systems are organized into parallel neuronal pathways that process distinct aspects of incoming stimuli. For example, in insects, second order olfactory projection neurons target both the mushroom body, which is required for learning, and the lateral horn (LH), which has been proposed to mediate innate olfactory behavior. Mushroom body neurons encode odors in a sparse population code, which does not appear stereotyped across animals. In contrast the functional principles of odor coding in the LH remain poorly understood. We have carried out a comprehensive anatomical analysis of the Drosophila LH, counting ~1400 neurons; combining genetic driver lines, anatomical and functional criteria, we identify 165 LHN cell types. We then show that genetically labeled LHNs have stereotyped odor responses across animals for 33 of these cell types. LHN tuning can be ultra-sparse (1/40 odors tested), but on average single LHNs respond to three times more odors than single projection neurons. This difference can be rationalized by our observation that LHNs are better odor categorizers, likely due to pooling of input projection neurons responding to different odors of the same category. Our results reveal some of the principles by which a higher sensory processing area can extract innate behavioral significance from sensory stimuli.

We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <, 19 pages, 8 figures, accepted for publication in ApJL

SummaryThe same sensory signal can be interpreted differently according to context. A new study in Drosophila uses cell-type-specific tools to identify neural circuits that integrate context during olfactory processing and surprisingly implicates memory-recall neurons.

Access the CPD MCQs for this issue online here ### Key points Compared with systemic analgesia, regional anaesthesia provides improved postoperative analgesia, reduced pain intensity, less postoperative nausea and vomiting (PONV), and increased patient satisfaction.1 The introduction of ultrasound guidance has been a marked advance in the practice of regional anaesthesia. This article will focus on ultrasound-guided (USG) peripheral nerve blocks (PNBs) of the upper limb. Traditionally, PNB has been reliant on surface landmark-based (LB) techniques aided by fascial clicks, loss of resistance, and neurostimulation for peripheral nerves with a motor component. Consequently, LB techniques of PNB in the upper limb have been restricted to sites at the elbow and wrist where surface landmarks are readily identified.2 Injection at these levels has the potential for neurological and vascular injury. Using ultrasound guidance the practitioner is no longer limited to the elbow and wrist. Peripheral nerves can be identified and traced to alternative sites where local anaesthetic (LA) can be safely injected without the risk of neurovascular injury. Variations in upper limb anatomy are commonly identified by ultrasonography and may, in part, explain the documented high incidence of block failure using traditional methods. USG selective PNB can also limit the extent of motor block or avoid it entirely by targeting sensory …

Summary The behavioral response to a sensory stimulus may depend on both learned and innate neuronal representations. How these circuits interact to produce appropriate behavior is unknown. In Drosophila, the lateral horn (LH) and mushroom body (MB) are thought to mediate innate and learned olfactory behavior, respectively, although LH function has not been tested directly. Here we identify two LH cell types (PD2a1 and PD2b1) that receive input from an MB output neuron required for recall of aversive olfactory memories. These neurons are required for aversive memory retrieval and modulated by training. Connectomics data demonstrate that PD2a1 and PD2b1 neurons also receive direct input from food odor-encoding neurons. Consistent with this, PD2a1 and PD2b1 are also necessary for unlearned attraction to some odors, indicating that these neurons have a dual behavioral role. This provides a circuit mechanism by which learned and innate olfactory information can interact in identified neurons to produce appropriate behavior. Video Abstract, Highlights • Specific Drosophila lateral horn neurons mediate innate attraction to food odors • The same neurons receive plastic odor information from the mushroom body • Recall after associative learning depends on reduced drive to lateral horn neurons • Connectomics circuit for integration of learned and innate odor representations, Sensory stimuli can engage both learned and innate behaviors. Dolan et al. identify neurons in Drosophila that directly integrate unlearned and plastic odor representations; they are required for innate approach to food odors but also learned aversive recall.

Efforts to map neural circuits have been galvanized by the development of genetic technologies that permit the manipulation of targeted sets of neurons in the brains of freely behaving animals. The success of these efforts relies on the experimenter’s ability to target arbitrarily small subsets of neurons for manipulation, but such specificity of targeting cannot routinely be achieved using existing methods. In Drosophila melanogaster, a widely-used technique for refined cell type-specific manipulation is the Split GAL4 system, which augments the targeting specificity of the binary GAL4-UAS (Upstream Activating Sequence) system by making GAL4 transcriptional activity contingent upon two enhancers, rather than one. To permit more refined targeting, we introduce here the “Killer Zipper” (KZip+), a suppressor that makes Split GAL4 targeting contingent upon a third enhancer. KZip+ acts by disrupting both the formation and activity of Split GAL4 heterodimers, and we show how this added layer of control can be used to selectively remove unwanted cells from a Split GAL4 expression pattern or to subtract neurons of interest from a pattern to determine their requirement in generating a given phenotype. To facilitate application of the KZip+ technology, we have developed a versatile set of LexAop-KZip+ fly lines that can be used directly with the large number of LexA driver lines with known expression patterns. KZip+ significantly sharpens the precision of neuronal genetic control available in Drosophila and may be extended to other organisms where Split GAL4-like systems are used.

Regional anaesthesia has many advantages over systemic analgesia alone for postoperative pain and rehabilitation. Advances in continuous peripheral nerve block techniques enable the benefits of single injection blockade to be extended, providing prolonged, site-specific analgesia. A wide range of equipment, local anaesthetic solutions and adjuvants can be used to provide peripheral nerve blockade. In this article we review equipment, drugs, techniques, indications, benefits and potential complications of peripheral nerve blockade, focussing on continuous perineural catheter techniques.