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Coronavirus disease 2019 (COVID-19) patients have manifested a variety of neurological complications, and there is still much to reveal regarding the neurotropism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Human stem cell-derived brain organoids offer a valuable in vitro approach to study the cellular effects of SARS-CoV-2 on the brain. Here we used human embryonic stem cell-derived cortical organoids to investigate whether SARS-CoV-2 could infect brain tissue in vitro and found that cortical organoids could be infected at low viral titers and within 6 h. Importantly, we show that glial cells and cells of the choroid plexus were preferentially targeted in our model, but not neurons. Interestingly, we also found expression of angiotensin-converting enzyme 2 in SARS-CoV-2 infected cells; however, viral replication and cell death involving DNA fragmentation does not occur. We believe that our model is a tractable platform to study the cellular effects of SARS-CoV-2 infection in brain tissue., Graphical abstract, In this article, Hsieh and colleagues investigated the neurotropism of the virus responsible for COVID-19, SARS-CoV-2. Using human ESC-derived brain organoids, this study found that SARS-CoV-2 can infect these organoids at low viral loads, but does not replicate within 4 days post infection. Specifically, SARS-CoV-2 preferentially targeted glial cells and cells of the choroid plexus in this model.

Epilepsy is a common neurological disorder characterized by recurrent and unprovoked seizures due to neuronal hyperactivity. A large proportion of epilepsy cases begin during childhood. Causes of epilepsy include stroke, infections, brain injury, genetic factors, or other factors that alter brain structure and development, but in up to 50% of cases the cause is unknown. Approximately 35% of patients have refractory seizures that do not respond to medication. Animal models and in vitro cultures have contributed to our understanding of epilepsy, but there is a clear need for better models to explore the human brain in normal and pathological conditions. Human pluripotent stem cell (PSC) technologies opened the door for new models for analyzing brain development and disease, especially conditions with a genetic component. Initially, PSCs were differentiated into 2-dimensional cultures of a homogenous population of neural cells, such as glutamatergic excitatory or γ-aminobutyric acidergic inhibitory neurons, as well as glial cells. Nevertheless, these cultures lacked the structure and complexity of a human brain. In the last decade, PSC technology has advanced to the next level through the development of 3-dimensional culture, called organoids. These organoids recapitulate features of the human brain that are missing in animal models, enabling a deeper study of the human brain. In this review, we will summarize the current status of organoid research and its application to epilepsy.

Opioid misuse among pregnant women is rapidly increasing in the United States. The number of maternal opioid-related diagnoses increased by 131% in the last 10 years, resulting in an increased number of infants exposed to opioidsin uteroand a subsequent increase in infants developing neonatal abstinence syndrome (NAS). The most prescribed treatment to combat maternal opioid use disorder is buprenorphine, a partial μ-opioid receptor agonist and κ-opioid receptor antagonist. Buprenorphine treatment effectively reduces NAS but has been associated with disrupted cortical development and neurodevelopmental consequences in childhood. Less is known about the long-term neurodevelopmental consequences following buprenorphine exposurein utero. Previous research has shown that gestational buprenorphine exposure can induce anxiety-like and depressive-like phenotypes in adult rats, suggesting that exposure to buprenorphinein uteromay render individuals more susceptible to psychiatric illness in adulthood. A common pathology observed across multiple psychiatric illnesses is dopamine system dysfunction. Here, we administered the highly-abused opioid, oxycodone (10 mg/kg, i.p.) or a therapeutic used to treat opioid use disorder, buprenorphine (1 mg/kg, i.p) to pregnant Sprague Dawley rats from gestational day 11 through 21, then examined neurophysiological alterations in the mesolimbic dopamine system and dopamine-dependent behaviors in adult offspring. We found that gestational exposure to buprenorphine or oxycodone increases dopamine neuron activity in adulthood. Moreover, prenatal buprenorphine exposure disrupts the afferent regulation of dopamine neuron activity in the ventral tegmental area (VTA). Taken together, we posit that gestational buprenorphine or oxycodone exposure can have profound effects on the mesolimbic dopamine system in adulthood.

Objectives: This study aims to estimate the prevalence of sinus tachycardia in hospitalized patients with mild COVID-19 infection and to identify the clinical, radiological, and biological characteristics associated with sinus tachycardia. Methods: A retrospective cohort study was conducted on patients with mild COVID-19 infection and sinus tachycardia during hospitalization. Outcomes measured included incidences of venous thromboembolism, high-dependency/intensive care unit admission, laboratory parameters, and radiological findings. Results: A total of 236 COVID-19 positive patients admitted to Singapore General Hospital isolation general wards from 1 June 2020 to 30 June 2020 were included in this study. Ninety-seven (41.1%) patients had sinus tachycardia on or during their admission. All patients were monitored in general wards and discharged to community quarantine facilities. None required oxygen support or high-dependency/intensive care unit admission. Sinus tachycardia was associated with increased C-reactive protein level (odds ratio = 1.033, 95% confidence interval = 1.002–1.066), abnormal chest X-ray findings (odds ratio = 3.142, 95% confidence interval = 1.390–7.104), and longer hospitalization (odds ratio = 1.117, 95% confidence interval = 1.010–1.236). There was no significant statistical association between sinus tachycardia and incidences of venous thromboembolism. Conclusion: This study suggests that patients with mild COVID-19 infection and concurrent sinus tachycardia are more likely to have higher inflammatory marker levels, abnormal imaging, and prolonged hospitalization. However, no significant association between sinus tachycardia and thromboembolism is identified in mild COVID-19 infection.

The coronavirus disease 2019 is a devastating illness that has infected millions of people since the beginning of year 2020, through its multi-systemic manifestations that range widely in severity. Because current knowledge on the types and severities of medical illnesses encountered by patients who recovered from coronavirus disease 2019 is limited, it remains unknown whether these illnesses are direct sequelae of coronavirus disease 2019 infection or unrelated coincidences. In this article, we summarize the evidence currently available on post-coronavirus disease 2019 medical complications and propose directions for studying the long-term complications of coronavirus disease 2019 in the future.

This study analyzes online customer reviews in order to investigate customers' preferences regarding cosmetic products. Based on the marketing firm theory, this research explores the possibility of enhancing the bilateral contingent relationships between the customer and the marketing firm within the cosmetics domain. Hence, this study applies market‐search concepts by extracting customer reviews and employing text analytics to identify reinforcers and factors in cosmetic products, which customers are expecting, and their sentiments towards them. Our results suggest that some reinforcers are shared among all customers, but some vary among the different customer segments based on their age and skin tone.

In the mammalian hippocampus, adult-born granule cells (abGCs) contribute to the function of the dentate gyrus (DG). Disruption of the DG circuitry causes spontaneous recurrent seizures (SRS), which can lead to epilepsy. Although abGCs contribute to local inhibitory feedback circuitry, whether they are involved in epileptogenesis remains elusive. Here, we identify a critical window of activity associated with the aberrant maturation of abGCs characterized by abnormal dendrite morphology, ectopic migration, and SRS. Importantly, in a mouse model of temporal lobe epilepsy, silencing aberrant abGCs during this critical period reduces abnormal dendrite morphology, cell migration, and SRS. Using mono-synaptic tracers, we show silencing aberrant abGCs decreases recurrent CA3 back-projections and restores proper cortical connections to the hippocampus. Furthermore, we show that GABA-mediated amplification of intracellular calcium regulates the early critical period of activity. Our results demonstrate that aberrant neurogenesis rewires hippocampal circuitry aggravating epilepsy in mice., Adult-born granule cells integrate in hippocampal circuitry and contribute to hippocampal function. Here, the authors show that a critical period of neuronal activity regulates aberrant neurogenesis to rewire hippocampal circuitry and drive seizures in a mouse model of epilepsy.

Despite large schooling and learning gains in many developing countries, children in highly deprived areas are often unlikely to achieve even basic literacy and numeracy. We study how much of this problem can be resolved using a multi-pronged intervention combining three interventions known to be separately effective. We conducted a cluster-randomized trial in The Gambia evaluating a literacy and numeracy intervention designed for primary-aged children in remote parts of poor countries. The intervention combines para teachers delivering after-school supplementary classes, scripted lesson plans, and frequent monitoring focusing on improving teacher practice (coaching). A similar intervention previously demonstrated large learning gains in rural India. After three academic years, Gambian children allocated to the intervention scored 46 percentage points (3.2 SD) better on a combined literacy and numeracy test than control children. Our results demonstrate that, in this type of area, aggressive interventions can yield far greater learning gains than previously shown.

Background Integrated community case management (CCM) has led to reductions in child mortality in Malawi resulting from illnesses such as malaria, pneumonia, and diarrhea. However, adherence to CCM guidelines is often poor, potentially leading to inappropriate clinical decisions and poor outcomes. We determined the impact of an e-CCM app on the referral, reconsultation, and hospitalization rates of children presenting to village clinics in Malawi. Objective We determined the impact of an electronic version of a smartphone-based CCM (e-CCM) app on the referral, reconsultation, and hospitalization rates of children presenting to village clinics in Malawi. Methods We used a stepped-wedge, cluster-randomized trial to compare paper-based CCM (control) with and without the use of an e-CCM app on smartphones from November 2016 to February 2017. A total of 102 village clinics from 2 districts in northern Malawi were assigned to 1 of 6 clusters, which were randomized on the sequencing of the crossover from the control phase to the intervention phase as well as the duration of exposure in each phase. Children aged ≥2 months to Results A total of 6965 children were recruited—49.11% (3421/6965) in the control phase and 50.88% (3544/6965) in the intervention phase. After adjusting for calendar time, children in the intervention phase were more likely to be urgently referred to a higher-level health facility than children in the control phase (odds ratio [OR] 2.02, 95% CI 1.27-3.23; P=.003). Overall, children in the intervention arm had lower odds of attending a repeat health surveillance assistant consultation (OR 0.45, 95% CI 0.34-0.59; P Conclusions The addition of e-CCM decision support by using smartphones led to a greater proportion of children being referred to higher-level facilities, with no apparent increase in hospital admissions or repeat consultations in village clinics. Our findings provide support for the implementation of e-CCM tools in Malawi and other low- and middle-income countries with a need for ongoing assessments of effectiveness and integration with national digital health strategies. Trial Registration ClinicalTrials.gov NCT02763345; https://clinicaltrials.gov/ct2/show/NCT02763345

The misuse of opioids has reached epidemic proportions over the last decade, with over 2.1 million people in the U.S. suffering from substance use disorders related to prescription opioid pain relievers. This increase in opioid misuse affects all demographics of society, including women of child-bearing age, which has led to a rise in opioid use during pregnancy. Opioid use during pregnancy has been associated with increased risk of obstetric complications and adverse neonatal outcomes, including neonatal abstinence syndrome. Currently, opioid use disorder in pregnant women is treated with long-acting opioid agonists, including buprenorphine. Although buprenorphine reduces illicit opioid use during pregnancy and improves infant outcomes at birth, few long-term studies of the neurodevelopmental consequences have been conducted. The goal of the current experiments was to examine the effects of buprenorphine on the development of the cortex using fetal brain tissue, 3D brain cultures, and rodent models. First, we demonstrated that we can grow cortical and subpallial spheroids, which model the cellular diversity, connectivity, and activity of the developing human brain. Next, we show that cells in the developing human cortex express the nociceptin opioid (NOP) receptor and that buprenorphine can signal through this receptor in cortical spheroids. Using subpallial spheroids to grow inhibitory interneurons, we show that buprenorphine can alter interneuron development and migration into the cortex. Finally, using a rodent model of prenatal buprenorphine exposure, we demonstrate that alterations in interneuron distribution can persist into adulthood. Together, these results suggest that more research is needed into the long-lasting consequences of buprenorphine exposure on the developing human brain.

SummaryMounting evidence suggests that cognitive deficits associated with various neurological disorders may arise in part from a small population of dysregulated adult-born neurons in the dentate gyrus (DG). How these dysregulated adult-born neurons contribute to brain-wide network maladaptation and subsequent cognitive deficits remains unknown. Using an established mouse model with a small number of time-stamped dysregulated adult-born immature neurons and spatial memory deficits, we performed resting state functional magnetic resonance imaging and found that approximately 500 deficient immature neurons (in vivo fiber photometry recording, we demonstrated that dysregulated adult-born neurons induce aberrant activity and synchrony in local hippocampal CA3 and CA1 regions, as well as distal medial-dorsal thalamus and IC regions during a spatial memory process. These results suggest that a few hundred dysregulated adult-born immature neurons can impact brain-wide network dynamics across several anatomically discrete regions and collectively contribute to impaired cognitive functions.

Objectives:Patients with COVID-19 may present with respiratory syndromes indistinguishable from those caused by common viruses. Early isolation and containment is challenging. Although screening all patients with respiratory symptoms for COVID-19 has been recommended, the practicality of such an effort has yet to be assessed.Methods:Over a 6-week period during a SARS-CoV-2 outbreak, our institution introduced a “respiratory surveillance ward” (RSW) to segregate all patients with respiratory symptoms in designated areas, where appropriate personal protective equipment (PPE) could be utilized until SARS-CoV-2 testing was done. Patients could be transferred when SARS-CoV-2 tests were negative on 2 consecutive occasions, 24 hours apart.Results:Over the study period, 1,178 patients were admitted to the RSWs. The mean length-of-stay (LOS) was 1.89 days (SD, 1.23). Among confirmed cases of pneumonia admitted to the RSW, 5 of 310 patients (1.61%) tested positive for SARS-CoV-2. This finding was comparable to the pickup rate from our isolation ward. In total, 126 HCWs were potentially exposed to these cases; however, only 3 (2.38%) required quarantine because most used appropriate PPE. In addition, 13 inpatients overlapped with the index cases during their stay in the RSW; of these 13 exposed inpatients, 1 patient subsequently developed COVID-19 after exposure. No patient–HCW transmission was detected despite intensive surveillance.Conclusions:Our institution successfully utilized the strategy of an RSW over a 6-week period to contain a cluster of COVID-19 cases and to prevent patient–HCW transmission. However, this method was resource-intensive in terms of testing and bed capacity.

Summary: In the adult brain, new dentate granule cells integrate into neural circuits and participate in hippocampal functioning. However, when and how they initiate this integration remain poorly understood. Using retroviral and live-imaging methods, we find that new neurons undergo neurite remodeling for competitive horizontal-to-radial repositioning in the dentate gyrus prior to circuit integration. Gene expression profiling, lipidomics analysis, and molecular interrogation of new neurons during this period reveal a rapid activation of sphingolipid signaling mediated by sphingosine-1-phosphate receptor 1. Genetic manipulation of this G protein-coupled receptor reveals its requirement for successful repositioning of new neurons. This receptor is also activated by hippocampus-engaged behaviors, which enhances repositioning efficiency. These findings reveal that activity-dependent sphingolipid signaling regulates cellular repositioning of new dentate granule cells. The competitive horizontal-to-radial repositioning of new neurons may provide a gating strategy in the adult brain to limit the integration of new neurons into pre-existing circuits. : Yang et al. show that prior to circuit integration, adult-born dentate granule cells undergo horizontal-to-radial transitioning, which is regulated by sphingolipid signaling via sphingosine-1-phosphate receptor 1. Keywords: G protein-coupled receptor, electrophysiological maturation, dentate granule cell, environmental enrichment, lipidomics, adult hippocampal neurogenesis, circuit integration initiation, sphingosine-1-phosphate receptor 1, hippocampus behavior-engaged activation

BackgroundIntegrated community case management (CCM) has led to reductions in child mortality in Malawi from illnesses such as malaria, pneumonia and diarrhoea. However, adherence to CCM guidelines is often poor, potentially leading to inappropriate clinical decisions and outcomes. We determined the impact of an electronic version of CCM (eCCM) application on referral, re-consultation and hospitalization rates of children presenting to village clinics in Malawi.MethodsA stepped-wedge cluster-randomized trial compared paper-based CCM (control) with and without use of an eCCM app on smartphones from November 2016 to April 2017.A total of 102 village clinics from two districts in Northern Malawi were assigned to one of six clusters which were randomized to the sequencing of crossover from the control to the intervention phases, as well as the duration of exposure in each phase. Children ≥2 months to ResultsA total of 6965 children were recruited, 3421 in the control and 3544 in the intervention phase. After adjusting for calendar time, children in the intervention phase were more likely to be urgently referred to a higher-level health facility compared with children in the control phase (OR 2.02, 95% CI 1.27-3.23; p0.05).ConclusionsAddition of eCCM decision support led to a greater proportion of children being referred to higher-level facilities, with no apparent increase in hospital admissions or repeat consultations in village clinics. Our findings provide support for the implementation of eCCM tools in Malawi and other Low and Middle Income Countries (LMIC), with a need for ongoing assessment of effectiveness and integration with national digital health strategies.Trial registrationhttp://ClinicalTrials.gov; NCT02763345. Registered 3 May 2016

Early Seizure Activity Accelerates Depletion of Hippocampal Neural Stem Cells and Impairs Spatial Discrimination in an Alzheimer’s Disease ModelFu CH, Iascone DM, Petrof I, Hazra A, Zhang X, Pyfer ...

Children in many extremely poor, remote regions are growing up illiterate and innumerate despite high reported school enrollment ratios. Possible explanations for such poor outcomes include demand – for example, low perceived returns to education compared to opportunity cost; and supply – poor state provision and inability of parents to coordinate and finance better schooling. We conducted a cluster-randomized trial in rural Guinea Bissau to understand the effectiveness and cost of concerted supply-based interventions in such contexts. Our intervention created simple schools offering four years of education to primary-school aged children in lieu of the government. At endline, children receiving the intervention scored 58.1 percentage points better than controls on early grade reading and math tests, demonstrating that the intervention taught children to read and perform basic arithmetic, from a counterfactual condition of very high illiteracy. Our results provide evidence that particularly needy areas may require more concerted, dramatic interventions in education than those usually considered, but that such interventions hold great potential for increasing education levels among the world’s poorest people.

Epilepsy is a disorder of the central nervous system characterized by spontaneous recurrent seizures. Although current therapies exist to control the number and severity of clinical seizures, there are no pharmacological cures or disease-modifying treatments available. Use of transgenic mouse models has allowed an understanding of neural stem cells in their relation to epileptogenesis in mesial temporal lobe epilepsy. Further, with the significant discovery of factors necessary to reprogram adult somatic cell types into pluripotent stem cells, it has become possible to study monogenic epilepsy-in-a-dish using patient-derived neurons. This discovery along with some of the newest technological advances in recapitulating brain development in a dish has brought us closer than ever to a platform in which to study and understand the mechanisms of this disease. These technologies will be critical in understanding the mechanism of epileptogenesis and ultimately lead to improved therapies and precision medicine for patients with epilepsy.

Summary Currently, all methods for converting non-neuronal cells into neurons involve injury to the brain; however, whether neuronal transdifferentiation can occur long after the period of insult remains largely unknown. Here, we use the transcription factor NEUROD1, previously shown to convert reactive glial cells to neurons in the cortex, to determine whether astrocyte-to-neuron transdifferentiation can occur under physiological conditions. We utilized adeno-associated virus 9 (AAV9), which crosses the blood-brain barrier without injury, to deliver NEUROD1 to astrocytes through an intravascular route. Interestingly, we found that a small, but significant number of non-reactive astrocytes converted to neurons in the striatum, but not the cortex. Moreover, astrocytes cultured to minimize their proliferative potential also exhibited limited neuronal transdifferentiation with NEUROD1 expression. Our results show that a single transcription factor can induce astrocyte-to-neuron conversion under physiological conditions, potentially facilitating future clinical approaches long after the acute injury phase., Highlights • Intravascular AAV9 efficiently targets astrocytes in the cortex and striatum • NEUROD1 can convert a small, but significant number of astrocytes to neurons in vivo • NEUROD1 induces limited neuronal transdifferentiation in vitro • Injury-related factors may be important in neuronal conversion strategies, In this article, Hsieh and colleagues use AAV9 viral infection to selectively target and overexpress NEUROD1 in astrocytes in the absence of injury to the CNS. The authors show that NEUROD1 is capable of converting a small, but significant number of astrocytes to neurons in vivo in the absence of reactive gliosis.

Background: Inappropriate use of antibiotics in hospitalized settings contributes to the selection and emergence of antimicrobial-resistant pathogens. This trend is particularly challenging in resource-constrained settings where the high burden of infectious diseases, combined with suboptimal infection prevention and control measures, are further complicated by limited access to reliable microbiological services to inform antimicrobial prescription at the patient level. In this study, we describe the use of antibiotics in selected Haitian hospitals; we aimed to create a baseline to inform antimicrobial stewardship interventions. Methods: WHO/PAHO Hospital Antibiotic Use Point Prevalence Survey (HAMU-PPS) were conducted in 6 acute-care Haitian hospitals: La-Paix and Hospital-Albert (June 2019) and Hospital-Universitaire-Justinien, Hospital-Bienfaisance-de-Pignon, Hospital-Sacre-Coeur-de-Milot, and Hospital Immaculee-Conception-des-Cayes (July-August 2019) in 6 different cities. Trained data collectors completed electronic forms using REDCap software including data related to antibiotic use, indications, and utilization of laboratory services from medical records of all inpatients meeting study inclusion criteria. Analyses were done using Microsoft Excel software (v2016). Results: In total, 510 inpatients records were surveyed. Patients ages ranged from 0 to 92, with median age of 27 years (IQR, 4–47); 269 were women (57.7%) and 239 were men (46.9%). The prevalence of antibiotic use was 73% (95% CI, 68.2%–81.8 %); this prevalence was 74.5% among men (178 of 239) and 70.6% among women (190 of 269). The highest antibiotic use was observed among children aged 1 antibiotic. In addition, 384 indications for antibiotic prescription were reported. Of the indications for antibiotics therapy, 49.7% (191 of 384) were for treatment, and 49% (188 of 384) were for prophylaxis. Of the treatments, 92% were empiric with 6% reported as targeted. Only 13% (50 of 370) of the patient records indicated that samples were taken for microbiological identification. Of those, 9 had results for culture, and 1 had results for drug susceptibility. The most commonly reported antibiotic was ceftriaxone (n = 110, 23%) followed by ampicillin (n = 153, 21.4%) and metronidazole (n = 135, 20%). Conclusions: This study shows high use of antibiotics among hospitalized patients in Haitian hospitals, especially in children aged Funding: NoneDisclosures: None

Three-dimensional (3D) organoid models derived from human pluripotent stem cells provide a platform for studying human development and understanding disease mechanisms. Most studies that examine biallelic inactivation of the cell cycle regulator Retinoblastoma 1 (RB1) and the link to retinoblastoma is in mice, however, less is known regarding the pathophysiological role of RB1 during human retinal development. To study the role of RB1 in early human retinal development and tumor formation, we generated retinal organoids from CRISPR/Cas9-derived RB1-null human embryonic stem cells (hESCs). We showed that RB is abundantly expressed in retinal progenitor cells in retinal organoids and loss of RB1 promotes S-phase entry. Furthermore, loss of RB1 resulted in widespread apoptosis and reduced the number of photoreceptor, ganglion, and bipolar cells. Interestingly, RB1 mutation in retinal organoids did not result in retinoblastoma formation in vitro or in the vitreous body of NOD/SCID immunodeficient mice. Together, our work identifies a crucial function for RB1 in human retinal development and suggests that RB1 deletion alone is not sufficient for tumor development, at least in human retinal organoids.

Three-dimensional brain organoids offer an unprecedented opportunity to study human brain development and disease. Characterizing context-specific organoid behaviors from local field potential (LFP) signals presents many machine learning challenges yet to be adequately addressed. We present in this paper classical machine learning and deep learning solutions to identify the LFP signatures unique to CHD2-mutant hESCs organoids and characterize their changes over time. We showed that a support vector machine (SVM) approach selected five frequency band-power features for 6 and 9-month-old organoids and achieved respective 99.3% and 88.1% area under the curve (AUC) performances in differentiating CHD2-mutant organoids from control using top five band-power features. We also proposed a convolutional neural network (CNN) that successfully classified both month 6 and month 9 CHD2 mutant organoids from controlled organoids using raw LFP signals with AUCs of with 99.6% and 99.7% respectively. We also reconstructed the discriminate features learned by CNN and showed their similarity and uniqueness compared with features selected by SVM.

Mesial temporal lobe epilepsy (mTLE), the most common form of medically refractory epilepsy in adults, is usually associated with hippocampal pathophysiology. Using rodent models of mTLE, many studies including work from our laboratory have shown that new neurons born around the onset of severe acute seizures known as status epilepticus (SE) are crucial for the process of epileptogenesis and targeting seizure-induced neurogenesis either genetically or pharmacologically can impact the frequency of chronic seizures. However, these studies are limited in their clinical relevance as none of them determines the potential of blocking new neurons generated after the epileptogenic insult to alleviate the development of chronic seizures. Therefore, using a pilocarpine-induced SE model of mTLE in mice of either sex, we show that >4 weeks of continuous and concurrent ablation of seizure-induced neurogenesis after SE can reduce the formation of spontaneous recurrent seizures by 65%. We also found that blocking post-SE neurogenesis does not lead to long-term seizure reduction as the effect was observed only transiently for 10 d with >4 weeks of continuous and concurrent ablation of seizure-induced neurogenesis. Thus, these findings provide evidence that seizure-induced neurogenesis when adequately reduced in a clinically relevant time period has the potential to transiently suppress recurrent seizures, but additional mechanisms need to be targeted to permanently prevent epilepsy development. SIGNIFICANCE STATEMENT Consistent with morphological and electrophysiological studies suggesting aberrant adult-generated neurons contribute to epilepsy development, ablation of seizure-induced new neurons at the time of the initial insult reduces the frequency of recurrent seizures. In this study, we show that continuous targeting of post-insult new neurons in a therapeutically relevant time period reduces chronic seizures; however, this effect does not persist suggesting possible additional mechanisms.

Genetically Engineered Human Cortical Spheroid Models of Tuberous Sclerosis Blair JD, Hockemeyer D, Bateup HS. Nat Med. 2018;24(10):1568-1578. doi:10.1038/s41591-018-0139-y. Epub 2018 Aug 20. PubMed PMID: 30127391; PubMed Central PMCID: PMC6261470. Tuberous sclerosis complex (TSC) is a multisystem developmental disorder caused by mutations in the TSC1 or TSC2 genes, whose protein products are negative regulators of mechanistic target of rapamycin complex 1 signaling. Hallmark pathologies of TSC are cortical tubers-regions of dysmorphic, disorganized neurons, and glia in the cortex that are linked to epileptogenesis. To determine the developmental origin of tuber cells, we established human cellular models of TSC by CRISPR-Cas9-mediated gene editing of TSC1 or TSC2 in human pluripotent stem cells (hPSCs). Using heterozygous TSC2 hPSCs with a conditional mutation in the functional allele, we show that mosaic biallelic inactivation during neural progenitor expansion is necessary for the formation of dysplastic cells and increased glia production in 3-dimensional cortical spheroids. Our findings provide support for the second-hit model of cortical tuber formation and suggest that variable developmental timing of somatic mutations could contribute to the heterogeneity in the neurological presentation of TSC.

Considerable evidence suggests loss of function mutations in the chromatin remodeler, CHD2, contribute to a broad spectrum of human neurodevelopmental disorders. However, it is unknown how CHD2 mutations lead to impaired brain function. Here we report mice with heterozygous mutations in Chd2 exhibit deficits in neuron proliferation and a shift in neuronal excitability that included divergent changes in excitatory and inhibitory synaptic function. Further in vivo experiments show Chd2(+/−) mice displayed aberrant cortical rhythmogenesis and severe deficits in long-term memory, consistent with phenotypes observed in humans. We identified broad, age-dependent transcriptional changes in Chd2(+/−) mice, including alterations in neurogenesis, synaptic transmission and disease-related genes. Deficits in interneuron density and memory caused by Chd2(+/−) were reproduced by Chd2 mutation restricted to a subset of inhibitory neurons and corrected by interneuron transplantation. Our results provide initial insight into how Chd2 haploinsufficiency leads to aberrant cortical network function and impaired memory.

In March 2016, meeting organizers Sebastian Jessberger and Hongjun Song brought together over 100 scientists from around the world to Cancun, Mexico to present the latest research on neurogenesis. The meeting covered diverse aspects of embryonic and adult neurogenesis with a focus on novel technologies, including chemogenetics and optogenetics, live cell two-photon imaging, cell fate reprogramming and human pluripotent stem cell models. This Meeting Review describes the exciting work that was presented and some of the emerging themes from the meeting.

Despite the immense growth of new anti-seizure drugs (ASDs), approximately one-third of epilepsy patients remain resistant to current treatment options. Advancements in whole genome sequencing technology continues to identify an increasing number of epilepsy-associated genes at a rate that is outpacing the development of in vivo animal models. Patient-derived induced pluripotent stem cells (iPSCs) show promise in providing a platform for modeling genetic epilepsies, high throughput drug screening, and personalized medicine. This is largely due to the ease of collecting donor cells for iPSC reprogramming, and their ability to be maintained in vitro, while preserving the patient's genetic background. In this review, we summarize the current state of iPSC research in epilepsy and closely related syndromes, discuss the growing need for high-throughput drug screening (HTS), and review the use of stem cell technology for the purpose of autologous transplantation for epilepsy stem cell therapy. Although the use of iPSC technology, as it applies to ASD discovery, is in its infancy, we highlight the significant progress that has been made in phenotype and assay development to facilitate systematic HTS for personalized medicine. This article is part of the special issue entitled 'New Epilepsy Therapies for the 21st Century - From Antiseizure Drugs to Prevention, Modification and Cure of Epilepsy'.

Background Inappropriate use of antimicrobials is one of the core contributors to antimicrobial resistance. While hospitals create high selection pressures on bacteria due to the high quantity and broader spectrum of antibiotics used, information on antimicrobial use at the patient level in the Caribbean is sparse. In response, PAHO implemented a standardized WHO methodology to engage national leaderships, build local capacity, and facilitate the use of data to inform antimicrobial stewardship programs (ASP) in the Caribbean. Methods Point prevalence surveys (PPS) were performed in four acute care hospitals in Barbados, Guyana and Saint Lucia between June and July 2018. Medical records of all inpatients were reviewed to collect information on antibiotic use, indications and use of laboratory services (Figure 1). A hospital questionnaire was used to assess hospital infrastructure, policy and practices, and monitoring and feedback systems (Figure 2). Training on PPS methods and electronic data collection tool in REDCap™ were provided to build local capacity and identify potential ASP leaderships. A standardized data validation, analysis and reporting system was built in R to streamline the process. Results and recommendations were disseminated to national authorities and stakeholders to support hospital and national decision-making and training for healthcare providers (Figure 3). Results A total of 60 physicians, nurses, pharmacists, laboratory technicians, and infection control specialists were trained and participated in the PPS. The survey collected records of 816 patients in which 442 (54%) were females and 374 (46%) were males. In total, 356 (44%) patients received 551 antibiotics. Overall, 300 (75%) of 398 indications for antibiotic use were treatment and 72 (18%) were prophylaxis. A higher use of parenteral antibiotics (79%) was observed compared with oral antibiotics (21%). Antibiotic prescribing patterns differed across hospitals. The most commonly used antibiotics were metronidazole (12%) and amoxicillin/clavulanate (11%). Conclusion The PPS method provided a feasible and effective way to collect baseline data and identify target areas for interventions. Engaging national leaderships and building local capacity offered a sustainable way in optimizing antimicrobial use in resource-limited settings. Disclosures All authors: No reported disclosures.

Background Antimicrobial resistance (AMR) to carbapenems in Enterobacteriaceae such as Klebsiella pneumoniae (KPN) is a major global public health concern. Infections caused by these pathogens are associated with high morbidity and mortality and perpetuated by limited safe alternative treatment options. This study aims to describe the antimicrobial susceptibility patterns amongst KPN to the carbapenems Latin America. Methods Surveillance laboratory data from 2000 to 2014 were obtained through the ReLAVRA network from 19 countries in Latin America. Longitudinal trends of mean percentage non-susceptibility for the region were conducted and evaluated with a significance level of P < 0.05. Results A total of 209,972 and 181,128 KPN isolates were reported from 2000 to 2014 for antibiotic susceptibility to imipenem and meropenem, respectively. From 2000 to 2014 an increasing trend was observed in the reported % KPN NS to imipenem (P < 0.0001) from 0.6% to 11.6% with an average annual percentage increase (AAPI) of 36.3% [95% CI: 39.8%–33%]. (Figure 1). Similarly, the % KPN NS to meropenem increased (P < 0.0001) from 0% in 2000 to 12.3% in 2014 with an AAPI of 49.5% [95% CI: 54%–44.6%] (Figure 2). For both antibiotics, the last 5 years of the timeframe (2010 to 2014) showed the highest rate of increase in NS. NS to carbapenems varied significantly between reporting countries, with the highest % KPN NS to imipenem and meropenem reported by Brazil, Guatemala, Nicaragua, and Peru. Conclusion The increase in KPN NS to carbapenems observed in Latin America threatens effective treatment of infections caused by this pathogen. The extremely limited treatment options could lead to further increases in morbidity and mortality. Strengthening health systems and core country capacity to identify and deal with these emerging high-risk pathogens and resistance mechanisms, through surveillance is vital to inform public health actions, control measures, mitigate outbreaks and support further development of Public health actions against AMR at country and regional level. Disclosures All authors: No reported disclosures.