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Abstract Microbial eukaryotes are important components of marine ecosystems, and the Marine Alveolates (MALVs) are consistently both abundant and diverse in global environmental sequencing surveys. MALVs are dinoflagellates that are thought to be parasites of other protists and animals, but the lack of data beyond ribosomal RNA gene sequences from all but a few described species means much of their biology and evolution remain unknown. Using single-cell transcriptomes from several MALVs and their free-living relatives, we show that MALVs evolved independently from two distinct, free-living ancestors and that their parasitism evolved in parallel. Phylogenomics shows one subgroup (MALV-II and -IV, or Syndiniales) is related to a novel lineage of free-living, eukaryovorous predators, the eleftherids, while the other (MALV-I, or Ichthyodinida) is related to the free-living predator Oxyrrhis and retains proteins targeted to a non-photosynthetic plastid. Reconstructing the evolution of photosynthesis, plastids, and parasitism in early-diverging dinoflagellates shows a number of parallels with the evolution of their apicomplexan sisters. In both groups, similar forms of parasitism evolved multiple times and photosynthesis was lost many times. By contrast, complete loss of the plastid organelle is infrequent and, when this does happen, leaves no residual genes.

Abstract The phylum Phoronida comprises filter-feeding invertebrates that live in a protective tube sometimes reinforced with particulate material from the surrounding environments. Animals with these characteristics make promising candidate hosts for symbiotic bacteria, given the constant interactions with various bacterial colonizers, yet phoronids are one of the very few animal phyla with no available microbiome data whatsoever. Here, by sequencing the V4 region of the 16S rRNA gene, we compare bacterial microbiomes in whole phoronids, including both tube and living tissues, with those associated exclusively to the isolated tube and/or the naked animal inside. We also compare these communities with those from the surrounding water. Phoronid microbiomes from specimens belonging to the same colony but collected a month apart were significantly different, and bacterial taxa previously reported in association with invertebrates and sediment were found to drive this difference. The microbiomes associated with the tubes are very similar in composition to those isolated from whole animals. However, just over half of bacteria found in whole specimens are also found both in tubes and naked specimens. In conclusion, phoronids harbour bacterial microbiomes that differ from those in the surrounding water, but the composition of those microbiomes is not stable and appears to change in the same colony over a relatively short time frame. Considering individual spatial/anatomical compartments, the phoronid tube contributes most to the whole-animal microbiome.

Abstract Phenotypic diversity and abundance drive salmon resilience in the face of increasing environmental variability. But what happens when human activities fundamentally alter the habitat complexity that drives this diversity? And how can we restore habitats to recover both diversity and abundance to support salmon persistence in a warming climate? Here, we looked at the impact of a large watershed restoration effort on the abundance and climate resilience of the three remaining core natural spring‐run Chinook Salmon populations in the California Central Valley (Butte, Mill, and Deer Creek). Butte Creek fish, which have floodplain access, had higher overall productivity and faster juvenile growth compared with Mill and Deer Creek populations, and the proportion of floodplain inundation was positively correlated with Butte Creek adult abundance two years later. While Butte Creek exhibited significant increases in abundance post‐restoration (~2000%), it generally exhibited lower phenotypic diversity and only a marginal increase in population stability after restoration based on the coefficient of variation (CV). In particular, Butte Creek salmon tended to exhibit larger drops in escapement following dry years (e.g., return years 2010, 2017) compared with Mill and Deer Creek populations, presumably due to limited inundation of its downstream floodplain. The late‐migrating juvenile strategy (i.e., yearling), which disproportionately supported Mill and Deer Creek populations during droughts, was uncommon among Butte Creek adults (averaging 60% of returns for Mill and Deer Creek vs. 0.3% for Butte Creek). Increased spring‐run stock complex stability was found, post‐restoration, when combining the three spring‐run populations (i.e., lower aggregate CV). However, among‐river pairwise correlations also suggested increased synchronization in population abundances post‐restoration, potentially due to increasing frequency and severity of extreme climatic events (e.g., droughts and ocean warming). This study underscores the importance of restoring a connected mosaic of aquatic habitats across modified landscapes, such as cold water refugia and floodplains, to preserve multiple (across‐population) life history pathways for increasing salmon stock complex stability and abundance. These landscape‐scale process‐based habitat restoration efforts are likely to be crucial for the successful long‐term recovery of vulnerable species in a rapidly changing climate.

Aquaculture now provides half of all aquatic protein consumed globally—with most current and future production occurring in low- and middle-income countries (LMICs). Concerns over the availability and application of effective policies to deliver safe and sustainable future supply have the potential to hamper further development of the sector. Creating healthy systems must extend beyond the simple exclusion of disease agents to tackle the host, environmental, and human drivers of poor outcomes and build new policies that incorporate these broader drivers. Syndemic theory provides a potential framework for operationalizing this One Health approach.

Abstract Background Microbial symbioses in marine invertebrates are commonplace. However, characterizations of invertebrate microbiomes are vastly outnumbered by those of vertebrates. Protists and fungi run the gamut of symbiosis, yet eukaryotic microbiome sequencing is rarely undertaken, with much of the focus on bacteria. To explore the importance of microscopic marine invertebrates as potential symbiont reservoirs, we used a phylogenetic-focused approach to analyze the host-associated eukaryotic microbiomes of 220 animal specimens spanning nine different animal phyla. Results Our data expanded the traditional host range of several microbial taxa and identified numerous undescribed lineages. A lack of comparable reference sequences resulted in several cryptic clades within the Apicomplexa and Ciliophora and emphasized the potential for microbial invertebrates to harbor novel protistan and fungal diversity. Conclusions Microscopic marine invertebrates, spanning a wide range of animal phyla, host various protist and fungal sequences and may therefore serve as a useful resource in the detection and characterization of undescribed symbioses. Video Abstract

Abstract Background Lateral canthal webbing is a known complication of blepharoplasty, which occurs when the lateral aspect of the upper blepharoplasty incision is taken below the equator of the lateral canthus. Removing excessive eyelid skin laterally can also result in a lateral canthal web. Currently, there is no standard approach for addressing this complication. Methods Retrospective review of single surgeon practice between 2011 and 2019. All patients underwent revision surgery using the proposed single Z-plasty technique. Results Twenty-three patients referred for lateral canthal web were included in the study. All patients had previous upper lid blepharoplasty, with the initial procedure occurring 8–63 months prior to the referral for revision. The majority of the blepharoplasties occurred in Ontario (n = 19), but some patients also underwent surgery in Alberta (n = 1), British Columbia (n = 1), and United States (n = 1). The initial surgeries were performed by a variety of specialities including plastic surgery (n = 16), otolaryngology (n = 4), ophthalmology (n = 2), and family medicine (n = 1). Following revision surgery using the single Z-plasty technique, all patients reported a subjective increase in functional and aesthetic satisfaction. No further revision surgery was required for any of these patients. Conclusion The single Z-plasty technique is simple, robust, and could be easily incorporated into any cosmetic practice to address this complication of blepharoplasty. Graphical Abstract

Introduction: Pain control following a total shoulder arthroplasty (TSA) is multifactorial. The current standard of care includes the utilization of a multimodal analgesic approach including breakthrough prescription opioid medication in an effort to provide postoperative analgesia. While this original opioid prescription is sufficient for the majority of patients, some go on to require prolonged opioid use. Our study investigated patient risk factors associated with opioid refill postsurgery. Methods: The Truven Marketscan® database was queried for all patients who underwent either a primary anatomic TSA or primary reverse TSA from 2010 to 2017. Opioid data were collected using National Drug Codes (NDC) from outpatient pharmacy claims. Only opioid-naïve patients were included. Patients were then grouped into 1 of 3 cohorts based on postoperative opioid use: 1) Patients with no additional refills, 2) patients with a minimum of one additional refill up through 6 months postoperatively, and 3) patients with additional refills and continued opioid use past 6 months. Results: Of the total of 17,706 opioid-naïve patients that underwent a TSA, 10,882 (61.5%) did not have any additional refills, 4473 (25.3%) required an additional prescription within 6 months after surgery, and 2351 (13.3%) had prolonged opioid use beyond 6 months postoperatively. A dose-dependent relationship was identified between initial opioid prescription quantity and risk for refill and prolonged use. The prolonged use group was prescribed an equivalent of 20.0 more 5 mg oxycodone pills than the no refill group and 12.7 more than the refill group (P

Abstract Objective The purpose of this study is to determine if removal of ethmoid cell septations as commonly performed in endoscopic sinus surgery leads to a change in orbital wall fracture patterns and the force required to create them. Methods Six fresh-frozen cadaveric heads were acquired and underwent endoscopic uncinectomy, maxillary antrostomy, and anterior and posterior ethmoidectomy on one, randomized, side. The contralateral sinuses were used as intra-specimen control. Hyaluronic acid gel globe injections were performed to simulate normal intra-ocular pressure. Post-op CT scans confirmed no orbital fractures or violation of the lamina papyracea prior to trauma testing. Orbital trauma was induced using a guided weight-drop technique. Both orbits were tested in random order, and sequentially higher drops were performed until both the test and control side demonstrated an orbital fracture on CT scan. Results In all six heads, the post-sinus surgery side incurred a medial orbital wall fracture, and no orbital floor fractures were identified. On the other hand, on the control side, all six heads incurred orbital floor fractures at drop heights equal to, or higher than, the surgical side. Fisher’s exact test demonstrated a significant difference in fracture pattern (p

The septum is a ventral forebrain structure known to regulate innate behaviors. During embryonic development, septal neurons are produced in multiple proliferative areas from neural progenitors following transcriptional programs that are still largely unknown. Here, we use a combination of single-cell RNA sequencing, histology, and genetic models to address how septal neuron diversity is established during neurogenesis. We find that the transcriptional profiles of septal progenitors change along neurogenesis, coinciding with the generation of distinct neuron types. We characterize the septal eminence, an anatomically distinct and transient proliferative zone composed of progenitors with distinctive molecular profiles, proliferative capacity, and fate potential compared to the rostral septal progenitor zone. We show that Nkx2.1-expressing septal eminence progenitors give rise to neurons belonging to at least three morphological classes, born in temporal cohorts that are distributed across different septal nuclei in a sequential fountain-like pattern. Our study provides insight into the molecular programs that control the sequential production of different neuronal types in the septum, a structure with important roles in regulating mood and motivation.

Abstract Viral diseases of crustaceans are increasingly recognised as challenges to shellfish farms and fisheries. Here we describe the first naturally-occurring virus reported in any clawed lobster species. Hypertrophied nuclei with emarginated chromatin, characteristic histopathological lesions of DNA virus infection, were observed within the hepatopancreatic epithelial cells of juvenile European lobsters (Homarus gammarus). Transmission electron microscopy revealed infection with a bacilliform virus containing a rod shaped nucleocapsid enveloped in an elliptical membrane. Assembly of PCR-free shotgun metagenomic sequencing produced a circular genome of 107,063 bp containing 97 open reading frames, the majority of which share sequence similarity with a virus infecting the black tiger shrimp: Penaeus monodon nudivirus (PmNV). Multiple phylogenetic analyses confirm the new virus to be a novel member of the Nudiviridae: Homarus gammarus nudivirus (HgNV). Evidence of occlusion body formation, characteristic of PmNV and its closest relatives, was not observed, questioning the horizontal transmission strategy of HgNV outside of the host. We discuss the potential impacts of HgNV on juvenile lobster growth and mortality and present HgNV-specific primers to serve as a diagnostic tool for monitoring the virus in wild and farmed lobster stocks.

The bacterial RND superfamily of efflux pumps mediate resistance to a variety of biocides, including Cu(I) and Ag(I) ions. Here we report four cryo-EM structures of the trimeric CusA pump in the presence of Cu(I). Combined with MD simulations, our data indicate that each CusA protomer within the trimer recognizes and extrudes Cu(I) independently.

Background: Although complications following hammertoe correction surgery are rare, older patients with comorbid conditions are often considered poorer operative candidates compared with younger, healthier patients because of a suspected increased risk of adverse outcomes. The aim of this study was to determine if the presence of multiple comorbidities was associated with increased complications or unsuccessful patient-reported outcomes following operative hammertoe correction in geriatric patients. Methods: Prospectively collected data was reviewed on 78 patients aged 60 years or older who underwent operative correction of hammertoe deformity. Patient demographics, comorbidities, and postoperative complications were recorded. Patient-reported outcomes were assessed using preoperative and postoperative visual analog scale for pain and Short Form Health Survey Physical and Mental Component Summary with 1 year of follow-up. Patients were divided into 2 groups based on number of comorbidities (0 or 1 vs > 2) and then compared. The average age of patients was 69.4 years and the prevalence of comorbidities in the study population was as follows: 11.5% smokers, 25.6% on blood thinners, 15.4% with rheumatoid arthritis, 7.7% with diabetes mellitus, 2.6% with peripheral arterial disease, 6.4% with chronic obstructive pulmonary disease, 11.5% with coronary artery disease, and 23.1% with osteoporosis. Results: Fifty-three patients (67.9%) had 0 or 1 comorbidity and 25 (32.1%) had 2 or more comorbidities. Compared to the 0 or 1 comorbidity group, the presence of multiple comorbidities was associated with an adjusted odds ratio (OR) for superficial wound infection of 4.18 ( P = .045) and deformity recurrence requiring surgery OR of 23.15 ( P = .032). Patient-reported outcomes were similar between comorbidity groups. Conclusions: This study further informs foot and ankle specialists to maintain increased surveillance for postoperative complications and unsuccessful outcomes in patients with multiple comorbidities. Although geriatric patients still report significant improvements in both pain and function, patients with underlying medical conditions should be counseled about their increased risks when pursuing operative hammertoe correction. Level of Evidence: Level III, retrospective comparative series.

The mouse cerebral cortex contains neurons that express choline acetyltransferase (ChAT) and are a potential local source of acetylcholine. However, the neurotransmitters released by cortical ChAT+ neurons and their synaptic connectivity are unknown. We show that the nearly all cortical ChAT+ neurons in mice are specialized VIP+ interneurons that release GABA strongly onto other inhibitory interneurons and acetylcholine sparsely onto layer 1 interneurons and other VIP+/ChAT+ interneurons. This differential transmission of ACh and GABA based on the postsynaptic target neuron is reflected in VIP+/ChAT+ interneuron pre-synaptic terminals, as quantitative molecular analysis shows that only a subset of these are specialized to release acetylcholine. In addition, we identify a separate, sparse population of non-VIP ChAT+ neurons in the medial prefrontal cortex with a distinct developmental origin that robustly release acetylcholine in layer 1. These results demonstrate both cortex-region heterogeneity in cortical ChAT+ interneurons and target-specific co-release of acetylcholine and GABA.

Abstract Background Preclinical studies suggest enhanced anti-tumor activity with combined radioimmunotherapy. We hypothesized that radiation (RT) + immunotherapy would associate with improved overall survival (OS) compared to immunotherapy or chemotherapy alone for patients with newly diagnosed metastatic non-small-cell lung cancer (NSCLC). Methods The National Cancer Database was queried for patients with stage IV NSCLC receiving chemotherapy or immunotherapy from 2013 to 2014. RT modality was classified as stereotactic radiotherapy (SRT) to intra- and/or extracranial sites or non-SRT external beam RT (EBRT). OS was analyzed using the Kaplan-Meier method and Cox proportional hazards models. Results In total, 44,498 patients were included (13% immunotherapy, 46.8% EBRT, and 4.7% SRT). On multivariate analysis, immunotherapy (hazard ratio [HR]:0.81, 95% confidence interval [CI]:0.78–0.83) and SRT (HR:0.78, 95%CI:0.70–0.78) independently associated with improved OS; however, the interaction term for SRT + immunotherapy was insignificant (p = 0.89). For immunotherapy patients, the median OS for no RT, EBRT, and SRT was 14.5, 10.9, and 18.2 months, respectively (p < 0.0001), and EBRT (HR:1.37, 95%CI:1.29–1.46) and SRT (HR:0.78, 95%CI:0.66–0.93) associated with OS on multivariate analysis. In the SRT subset, median OS for immunotherapy and chemotherapy was 18.2 and 14.3 months, respectively (p = 0.004), with immunotherapy (HR:0.82, 95%CI:0.69–0.98) associating with OS on multivariate analysis. Furthermore, for patients receiving SRT, biologically effective dose (BED) > 60 Gy was independently associated with improved OS (HR:0.79, 95%CI:0.70–0.90, p < 0.0001) on multivariate analysis with a significant interaction between BED and systemic treatment (p = 0.008). Conclusions Treatment with SRT associated with improved OS for patients with metastatic NSCLC irrespective of systemic treatment. The high survival for patients receiving SRT + immunotherapy strongly argues for evaluation in randomized trials.

ABSTRACT Resistance-nodulation-cell division multidrug efflux pumps are membrane proteins that catalyze the export of drugs and toxic compounds out of bacterial cells. Within the hydrophobe-amphiphile subfamily, these multidrug-resistant proteins form trimeric efflux pumps. The drug efflux process is energized by the influx of protons. Here, we use single-particle cryo-electron microscopy to elucidate the structure of the Acinetobacter baumannii AdeB multidrug efflux pump embedded in lipidic nanodiscs to a resolution of 2.98 Å. We found that each AdeB molecule within the trimer preferentially takes the resting conformational state in the absence of substrates. We propose that proton influx and drug efflux are synchronized and coordinated within the transport cycle. IMPORTANCE Acinetobacter baumannii is a successful human pathogen which has emerged as one of the most problematic and highly antibiotic-resistant Gram-negative bacteria worldwide. Multidrug efflux is a major mechanism that A. baumannii uses to counteract the action of multiple classes of antibiotics, such as β-lactams, tetracyclines, fluoroquinolones, and aminoglycosides. Here, we report a cryo-electron microscopy (cryo-EM) structure of the prevalent A. baumannii AdeB multidrug efflux pump, which indicates a plausible pathway for multidrug extrusion. Overall, our data suggest a mechanism for energy coupling that powers up this membrane protein to export antibiotics from bacterial cells. Our studies will ultimately inform an era in structure-guided drug design to combat multidrug resistance in these Gram-negative pathogens.

Astrocytes have emerged as integral partners with neurons in regulating synapse formation and function, but the mechanisms that mediate these interactions are not well understood. Here, we show that Sonic hedgehog (Shh) signaling in mature astrocytes is required for establishing structural organization and remodeling of cortical synapses in a cell type-specific manner. In the postnatal cortex, Shh signaling is active in a subpopulation of mature astrocytes localized primarily in deep cortical layers. Selective disruption of Shh signaling in astrocytes produces a dramatic increase in synapse number specifically on layer V apical dendrites that emerges during adolescence and persists into adulthood. Dynamic turnover of dendritic spines is impaired in mutant mice and is accompanied by an increase in neuronal excitability and a reduction of the glial-specific, inward-rectifying K+ channel Kir4.1. These data identify a critical role for Shh signaling in astrocyte-mediated modulation of neuronal activity required for sculpting synapses.

Adenovirus (AdV) infection elicits a strong immune response with the production of neutralizing antibodies and opsonization by complement and coagulation factors. One anti-hexon neutralizing antibody, called 9C12, is known to activate the complement cascade, resulting in the deposition of complement component C4b on the capsid, and the neutralization of the virus. The mechanism of AdV neutralization by C4b is independent of downstream complement proteins and involves the blockage of the release of protein VI, which is required for viral escape from the endosome. To investigate the structural basis underlying how C4b blocks the uncoating of AdV, we built a model for the complex of human adenovirus type-5 (HAdV5) with 9C12, together with complement components C1 and C4b. This model positions C4b near the Arg-Gly-Asp (RGD) loops of the penton base. There are multiple amino acids in the RGD loop that might serve as covalent binding sites for the reactive thioester of C4b. Molecular dynamics simulations with a multimeric penton base and C4b indicated that stabilizing interactions may form between C4b and multiple RGD loops. We propose that C4b deposition on one RGD loop leads to the entanglement of C4b with additional RGD loops on the same penton base multimer and that this entanglement blocks AdV uncoating.

BACKGROUND:Intensity-modulated radiation therapy (IMRT) has been used to limit treatment-related toxicity for patients with anal squamous cell carcinoma (SCC). The treatment outcomes and HPV characteristics for a cohort of patients receiving definitive concurrent chemotherapy and IMRT are reported. MATERIALS AND METHODS:52 patients with anal SCC were treated with IMRT and concurrent chemotherapy. Radiation was delivered sequentially to the pelvis and inguinal lymph nodes (45 Gy) and anal tumor (median dose, 54 Gy). Multiplex real-time PCR for 7 high-risk HPV subtypes (n = 22) and p16 immunohistochemistry (n = 21, rated on a 0, 1, and 2+ scale) were performed on available specimens. Survival was estimated using Kaplan-Meier analysis, and toxicities were recorded. RESULTS:Median follow-up was 33 months. Three-year freedom from locoregional failure (FFLRF), freedom from distant metastasis (FFDM), freedom from colostomy (FFC), and overall survival (OS) were 94%, 85%, 91%, and 90%, respectively. Acute grade 2+ skin, GI, and GU toxicities occurred in 83%, 71%, and 19% of evaluable patients, respectively. The rates of late grade 2+ GI and GU toxicities for evaluable patients (n = 32) were 28% and 9%, respectively. Of patients with available pathology, 91% and 71% were positive for HPV and p16 (2+), respectively. HPV genotypes included 16 (n = 17), 33 (n = 2), 18 (n = 1), and 45 (n = 1). HPV and p16 status were associated on Chi-square analysis (p = 0.07). Neither HPV nor p16 status was significantly associated with any clinical outcome. For HPV+ patients, 3-year FFLRF, FFDM, FFC, and OS were 100%, 69%, 100%, and 88%, respectively. CONCLUSIONS:In this patient cohort, disease control was excellent for anal SCC treated with definitive concurrent chemotherapy and IMRT, and treatment was well tolerated. HPV and p16 status were not prognostic for treatment outcomes which may be related to our small sample size.

[This corrects the article DOI: 10.1371/journal.pone.0194234.].

Glutaredoxin (Grx1) is a ubiquitously expressed thiol-disulfide oxidoreductase that specifically catalyzes reduction of S-glutathionylated substrates. Grx1 is known to be a key regulator of pro-inflammatory signaling, and Grx1 silencing inhibits inflammation in inflammatory disease models. Therefore, we anticipate that inhibition of Grx1 could be an anti-inflammatory therapeutic strategy. We used a rapid screening approach to test 504 novel electrophilic compounds for inhibition of Grx1, which has a highly reactive active-site cysteine residue (pKa 3.5). From this chemical library a chloroacetamido compound, CWR-J02, was identified as a potential lead compound to be characterized. CWR-J02 inhibited isolated Grx1 with an IC50 value of 32 μM in the presence of 1 mM glutathione. Mass spectrometric analysis documented preferential adduction of CWR-J02 to the active site Cys-22 of Grx1, and molecular dynamics simulation identified a potential non-covalent binding site. Treatment of the BV2 microglial cell line with CWR-J02 led to inhibition of intracellular Grx1 activity with an IC50 value (37 μM). CWR-J02 treatment decreased lipopolysaccharide-induced inflammatory gene transcription in the microglial cells in a parallel concentration-dependent manner, documenting the anti-inflammatory potential of CWR-J02. Exploiting the alkyne moiety of CWR-J02, we used click chemistry to link biotin azide to CWR-J02-adducted proteins, isolating them with streptavidin beads. Tandem mass spectrometric analysis identified many CWR-J02-reactive proteins, including Grx1 and several mediators of inflammatory activation. Taken together, these data identify CWR-J02 as an intracellularly effective Grx1 inhibitor that may elicit its anti-inflammatory action in a synergistic manner by also disabling other pro-inflammatory mediators. The CWR-J02 molecule provides a starting point for developing more selective Grx1 inhibitors and anti-inflammatory agents for therapeutic development.

We tested the hypothesis that a 6-week regimen of simvastatin would attenuate skeletal muscle adaptation to low-intensity exercise. Male C57BL/6J wildtype mice were subjected to 6-weeks of voluntary wheel running or normal cage activities with or without simvastatin treatment (20 mg/kg/d, n = 7-8 per group). Adaptations in in vivo fatigue resistance were determined by a treadmill running test, and by ankle plantarflexor contractile assessment. The tibialis anterior, gastrocnemius, and plantaris muscles were evaluated for exercised-induced mitochondrial adaptations (i.e., biogenesis, function, autophagy). There was no difference in weekly wheel running distance between control and simvastatin-treated mice (P = 0.51). Trained mice had greater treadmill running distance (296%, P

The cerebral cortex contains billions of neurons, and their disorganization or misspecification leads to neurodevelopmental disorders. Understanding how the plethora of projection neuron subtypes are generated by cortical neural stem cells (NSCs) is a major challenge. Here, we focused on elucidating the transcriptional landscape of murine embryonic NSCs, basal progenitors (BPs), and newborn neurons (NBNs) throughout cortical development. We uncover dynamic shifts in transcriptional space over time and heterogeneity within each progenitor population. We identified signature hallmarks of NSC, BP, and NBN clusters and predict active transcriptional nodes and networks that contribute to neural fate specification. We find that the expression of receptors, ligands, and downstream pathway components is highly dynamic over time and throughout the lineage implying differential responsiveness to signals. Thus, we provide an expansive compendium of gene expression during cortical development that will be an invaluable resource for studying neural developmental processes and neurodevelopmental disorders.

As the size of functional and structural MRI datasets expands, it becomes increasingly important to establish a baseline from which diagnostic relevance may be determined, a processing strategy that efficiently prepares data for analysis, and a statistical approach that identifies important effects in a manner that is both robust and reproducible. In this paper, we introduce a multivariate analytic approach that optimizes sensitivity and reduces unnecessary testing. We demonstrate the utility of this mega-analytic approach by identifying the effects of age and gender on the resting state networks of 603 healthy adolescents and adults (mean age: 23.4 years, range: 12 to 71 years). Data were collected on the same scanner, preprocessed using an automated analysis pipeline based in SPM, and studied using group independent component analysis. Resting state networks were identified and evaluated in terms of three primary outcome measures: time course spectral power, spatial map intensity, and functional network connectivity. Results revealed robust effects of age on all three outcome measures, largely indicating decreases in network coherence and connectivity with increasing age. Gender effects were of smaller magnitude but suggested stronger intra-network connectivity in females and more inter-network connectivity in males, particularly with regard to sensorimotor networks. These findings, along with the analysis approach and statistical framework described here, provide a useful baseline for future investigations of brain networks in health and disease.

Neuron-glia interactions play a critical role in the regulation of synapse formation and circuit assembly. Here we demonstrate that canonical Sonic hedgehog (Shh) pathway signaling in cortical astrocytes acts to coordinate layer-specific synaptic connectivity. We show that the Shh receptor Ptch1 is expressed by cortical astrocytes during development and that Shh signaling is necessary and sufficient to promote the expression of genes involved in regulating synaptic development and layer-enriched astrocyte molecular identity. Loss of Shh in layer V neurons reduces astrocyte complexity and coverage by astrocytic processes in tripartite synapses; conversely, cell-autonomous activation of Shh signaling in astrocytes promotes cortical excitatory synapse formation. Furthermore, Shh-dependent genes Lrig1 and Sparc distinctively contribute to astrocyte morphology and synapse formation. Together, these results suggest that Shh secreted from deep-layer cortical neurons acts to specialize the molecular and functional features of astrocytes during development to shape circuit assembly and function.

Effective species management depends on accurate estimates of population size. There are, however, no estimates of annual juvenile production for Central Valley spring-run Chinook Salmon (“spring run”), a highly imperiled species in California, making it difficult to evaluate population status and effectively manage key issues such as entrainment of this species at water diversions. In recognition of this critical information gap, we initiated an effort to develop a juvenile production estimate (JPE) for spring run, defined here as an annual forecast of the number of juvenile Central Valley spring-run Chinook Salmon that enter the Sacramento–San Joaquin Delta (“Delta”) from the Sacramento Valley. This metric would allow for a more robust scientific assessment of the population, which is needed to effectively manage water to reduce effects on spring run, a key condition of state permit requirements. To help guide this effort, we organized a workshop for stake-holders, managers, and scientists to review some of the key aspects of spring-run biology, examine the management and conservation importance of a JPE, identify knowledge gaps, introduce new tools, and discuss alternative approaches to forecasting the number of spring run emigrating from the Sacramento River drainage and into the Delta. This paper summarizes the spring-run biology, monitoring, and emergent methods for assessment considered at the workshop, as well as the guiding concepts identified by workshop participants necessary to develop a JPE for spring-run Chinook Salmon.

The septum is a ventral forebrain structure known to regulate innate behaviors. During embryonic development, septal neurons are produced in multiple proliferative areas from neural progenitors following transcriptional programs that are still largely unknown. Here, we use a combination of single-cell RNA sequencing, histology, and genetic models to address how septal neuron diversity is established during neurogenesis. We find that the transcriptional profiles of septal progenitors change along neurogenesis, coinciding with the generation of distinct neuron types. We characterize the septal eminence, an anatomically distinct and transient proliferative zone composed of progenitors with distinctive molecular profiles, proliferative capacity, and fate potential compared to the rostral septal progenitor zone. We show that Nkx2.1-expressing septal eminence progenitors give rise to neurons belonging to at least three morphological classes, born in temporal cohorts that are distributed across different septal nuclei in a sequential fountain-like pattern. Our study provides insight into the molecular programs that control the sequential production of different neuronal types in the septum, a structure with important roles in regulating mood and motivation.

BackgroundMild traumatic brain injury (mTBI) is a leading cause of sustained impairments in military service members, Veterans, and civilians. However, few treatments are available for mTBI, partially because the mechanism of persistent mTBI deficits is not fully understood.MethodsWe used magnetoencephalography (MEG) to investigate neuronal changes in individuals with mTBI following a passive neurofeedback-based treatment programme called IASIS. This programme involved applying low-intensity pulses using transcranial electrical stimulation (LIP-tES) with electroencephalography monitoring. Study participants included six individuals with mTBI and persistent post-concussive symptoms (PCS). MEG exams were performed at baseline and follow-up to evaluate the effect of IASIS on brain functioning.ResultsAt the baseline MEG exam, all participants had abnormal slow-waves. In the follow-up MEG exam, the participants showed significantly reduced abnormal slow-waves with an average reduction of 53.6 ± 24.6% in slow-wave total score. The participants also showed significant reduction of PCS scores after IASIS treatment, with an average reduction of 52.76 ± 26.4% in PCS total score.ConclusionsThe present study demonstrates, for the first time, the neuroimaging-based documentation of the effect of LIP-tES treatment on brain functioning in mTBI. The mechanisms of LIP-tES treatment are discussed, with an emphasis on LIP-tES's potentiation of the mTBI healing process.

An embryonic diapause in unfavourable conditions has allowed brine shrimp to thrive in hypersaline environments and, unexpectedly, mail-order sachets and small, novelty tanks. Marketed as Sea-Monkeys®, each kit involves a 3-step process to generate adult Artemia within a matter of weeks. Whether these kits also allow for the maintenance of a host-associated microbiome is unclear. Therefore, comparing five replicate tanks under the same culture conditions, we sequenced the 16S ribosomal small subunit (SSU) gene to analyse bacterial community compositions in adults, their surrounding tank water, and their feed. Adult Sea-Monkeys® harboured a bacterial microbiome that was clearly distinguishable from the tank water and food. Furthermore, individual tanks had a notable effect on fine-scale microbiome variation. Several Sea-Monkey bacterial variants appeared absent in environmental samples and included genera (Leucobacter and Microbacterium) known to confer desiccation resistance in other hosts. Although Sea-Monkeys® taxonomy is unclear, phylogenetic inference of the cytochrome c oxidase I (COXI) gene from the host animal suggests Sea-Monkeys® belong to the Artemia franciscana 'superspecies'. Overall, Sea-Monkeys® kits appear to be a convenient and scalable mesocosm for the study of host-microbiome interactions and could serve as a useful tool for future invertebrate microbiome research, outreach, and education. [ABSTRACT FROM AUTHOR]

BackgroundRelapses of multiple sclerosis decrease during pregnancy, when the hormone estriol is increased. Estriol treatment is anti-inflammatory and neuroprotective in preclinical studies. In a small single-arm study of people with multiple sclerosis estriol reduced gadolinium-enhancing lesions and was favourably immunomodulatory. We assessed whether estriol treatment reduces multiple sclerosis relapses in women.MethodsWe did a randomised, double-blind, placebo-controlled phase 2 trial at 16 academic neurology centres in the USA, between June 28, 2007, and Jan 9, 2014. Women aged 18-50 years with relapsing-remitting multiple sclerosis were randomly assigned (1:1) with a random permuted block design to either daily oral estriol (8 mg) or placebo, each in combination with injectable glatiramer acetate 20 mg daily. Patients and all study personnel, except for pharmacists and statisticians, were masked to treatment assignment. The primary endpoint was annualised relapse rate after 24 months, with a significance level of p=0.10. Relapses were confirmed by an increase in Expanded Disability Status Scale score assessed by an independent physician. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00451204.FindingsWe enrolled 164 patients: 83 were allocated to the estriol group and 81 were allocated to the placebo group. The annualised confirmed relapse rate was 0.25 relapses per year (95% CI 0.17-0.37) in the estriol group versus 0.37 relapses per year (0.25-0.53) in the placebo group (adjusted rate ratio 0.63, 95% CI 0.37-1.05; p=0.077). The proportion of patients with serious adverse events did not differ substantially between the estriol group and the placebo group (eight [10%] of 82 patients vs ten [13%] of 76 patients). Irregular menses were more common in the estriol group than in the placebo group (19 [23%] vs three [4%], p=0.0005), but vaginal infections were less common (one [1%] vs eight [11%], p=0.0117). There were no differences in breast fibrocystic disease, uterine fibroids, or endometrial lining thickness as assessed by clinical examination, mammogram, uterine ultrasound, or endometrial lining biopsy.InterpretationEstriol plus glatiramer acetate met our criteria for reducing relapse rates, and treatment was well tolerated over 24 months. These results warrant further investigation in a phase 3 trial.FundingNational Institutes of Health, National Multiple Sclerosis Society, Conrad N Hilton Foundation, Jack H Skirball Foundation, Sherak Family Foundation, and the California Community Foundation.