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Autism is characterized by two key diagnostic criteria including social deficits and repetitive behaviors. Although recent studies implicated ventral striatum in social deficits and dorsal striatum in repetitive behaviors, here we revealed coexisting and opposite morphologic and functional alterations in the dorsostriatal direct and indirect pathways, and such alterations in these two pathways were found to be responsible, respectively, for the two abovementioned different autism-like behaviors exhibited by male mice prenatally exposed to valproate. The alteration in direct pathway was characterized by a potentiated state of basal activity, with impairment in transient responsiveness of D1-MSNs during social exploration. Concurrent alteration in indirect pathway was a depressed state of basal activity, with enhancement in transient responsiveness of D2-MSNs during repetitive behaviors. A causal relationship linking such differential alterations in these two pathways to the coexistence of these two autism-like behaviors was demonstrated by the cell type-specific correction of abnormal basal activity in the D1-MSNs and D2-MSNs of valproate-exposed mice. The findings support those differential alterations in two striatal pathways mediate the two coexisting autism-like behavioral abnormalities, respectively. This result will help in developing therapeutic options targeting these circuit alterations.SIGNIFICANCE STATEMENT Autism is characterized by two key diagnostic criteria including social deficits and repetitive behaviors. Although a number of recent studies have implicated ventral striatum in social deficits and dorsal striatum in repetitive behaviors, but social behaviors need to be processed by a series of actions, and repetitive behaviors, especially the high-order repetitive behaviors such as restrictive interests, have its scope to cognitive and emotional domains. The current study, for the first time, revealed that prenatal valproate exposure induced coexisting and differential alterations in the dorsomedial striatal direct and indirect pathways, and that these alterations mediate the two coexisting autism-like behavioral abnormalities, respectively. This result will help in developing therapeutic options targeting these circuit alterations to address the behavioral abnormalities.
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Transtorno Autístico , Estriado Ventral , Camundongos , Animais , Masculino , Transtorno Autístico/metabolismo , Ácido Valproico , Comportamento Social , Estriado Ventral/metabolismoRESUMO
BACKGROUND: Cannabinoids and their derivatives attract strong interest due to the tremendous potential of their psychoactive effects for treating psychiatric disorders and symptoms. However, their clinical application is restricted by various side-effects such as impaired coordination, anxiety, and learning and memory disability. Adverse impact on dorsal striatum-dependent learning is an important side-effect of cannabinoids. As one of the most important forms of learning mediated by the dorsal striatum, reinforcement learning is characterized by an initial association learning phase, followed by habit learning. While the effects of cannabinoids on habit learning have been well-studied, little is known about how cannabinoids influence the initial phase of reinforcement learning. RESULTS: We found that acute activation of cannabinoid receptor type 1 (CB1R) by the synthetic cannabinoid HU210 induced dose-dependent impairment of association learning, which could be alleviated by intra-dorsomedial striatum (DMS) injection of CB1R antagonist. Moreover, acute exposure to HU210 elicited enhanced synaptic transmission in striatonigral "direct" pathway medium spiny neurons (MSNs) but not indirect pathway neurons in DMS. Intriguingly, enhancement of synaptic transmission that is also observed after learning was abolished by HU210, indicating cannabinoid system might disrupt reinforcement learning by confounding synaptic plasticity normally required for learning. Remarkably, the impaired response-reinforcer learning was also induced by selectively enhancing the D1-MSN (MSN that selectively expresses the dopamine receptor type 1) activity by virally expressing excitatory hM3Dq DREADD (designer receptor exclusively activated by a designer drug), which could be rescued by specifically silencing the D1-MSN activity via hM4Di DREADD. CONCLUSION: Our findings demonstrate dose-dependent deleterious effects of cannabinoids on association learning by disrupting plasticity change required for learning associated with the striatal direct pathway, which furthers our understanding of the side-effects of cannabinoids and the underlying mechanisms.
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Canabinoides , Aprendizagem por Associação , Canabinoides/metabolismo , Canabinoides/farmacologia , Corpo Estriado/metabolismo , Humanos , Neurônios/fisiologia , Transmissão SinápticaRESUMO
Background and Purpose: Systemic inflammation is recognized as a hallmark of stroke. We aimed to evaluate the prognostic value of various inflammatory factors using blood at admission in patients with aneurysmal subarachnoid hemorrhage. Methods: In a multicenter observational study of patients with aneurysmal subarachnoid hemorrhage, the counts of neutrophil, platelet, and lymphocyte were collected on admission. Patients were stratified based on neutrophil counts with propensity score matching to minimize confounding. We calculated the adjusted odds ratios with 95% CIs for the primary outcome of in-hospital mortality and hospital-acquired infections. Results: A total of 6041 patients were included in this study and 344(5.7%) of them died in hospital. Propensity score matching analyses indicated that compared with the lower neutrophil counts, higher neutrophil counts were associated with increased risk of in-hospital mortality (odds ratio, 1.53 [95% CI, 1.142.06]), hospital-acquired infections (odds ratio, 1.61 [95% CI, 1.381.79]), and delayed neurological ischemic deficits (odds ratio, 1.52 [95% CI, 1.091.97]). Moreover, out of all the inflammatory factors studied, neutrophil counts demonstrated the highest correlation with in-hospital mortality and hospital-acquired infections. Conclusions: Among patients with aneurysmal subarachnoid hemorrhage, high neutrophil counts at admission were associated with increased mortality and hospital-acquired infections. The neutrophil count is a simple, useful marker with prognostic value in patients with aneurysmal subarachnoid hemorrhage.
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Contagem de Leucócitos , Neutrófilos , Hemorragia Subaracnóidea/sangue , Hemorragia Subaracnóidea/mortalidade , Adulto , Idoso , Biomarcadores , Estudos de Coortes , Infecção Hospitalar/epidemiologia , Feminino , Mortalidade Hospitalar , Humanos , AVC Isquêmico/epidemiologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Accurate cropland map serves as the cornerstone of effective agricultural monitoring. Despite the continuous enrichment of remotely sensed cropland maps, pervasive inconsistencies have impeded their further application. This issue is particularly evident in areas with limited valid observations, such as southwestern China, which is characterized by its complex topography and fragmented parcels. In this study, we constructed multi-sourced samples independent of the data producers, taking advantage of open-source validation datasets and sampling to rectify the accuracy of ten contemporary cropland maps in southwestern China, decoded their inconsistencies, and generated a refined cropland map (CroplandSyn) by leveraging ten state-of-the-art remotely sensed cropland maps released from 2021 onwards using the self-adaptive threshold method. Validations, conducted at both prefecture and county scales, underscored the superiority of the refined cropland map, aligning more closely with national land survey data. The refined cropland map and samples are publicly available to users. Our study offers valuable insights for improving agricultural practices and land management in under-monitored areas by providing high-quality cropland maps and validation datasets.
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Autism spectrum disorders (ASD) represent a group of neurodevelopmental defects characterized by social deficits and repetitive behaviors. Alteration in Glycosylation patterns could influence the nervous system development and contribute to the molecular mechanism of ASD. Interaction of environmental factors with susceptible genes may affect expressions of glycosylation-related genes and thus result in abnormal glycosylation patterns. Here, we used an environmental factor-induced model of autism by a single intraperitoneal injection of 400 mg/kg valproic acid (VPA) to female rats at day 12.5 post-conception. Following confirmation of reduced sociability and increased self-grooming behaviors in VPA-treated offspring, we analyzed the alterations in the expression profile of glycan patterns and glycan-related genes by lectin microarrays and RNA-seq, respectively. Lectin microarrays detected 14 significantly regulated lectins in VPA rats, with an up-regulation of high-mannose with antennary and down-regulation of Siaα2-3 Gal/GalNAc. Based on the KEGG and CAZy resources, we assembled a comprehensive list of 961 glycan-related genes to focus our analysis on specific genes. Of those, transcription results revealed that there were 107 differentially expressed glycan-related genes (DEGGs) after VPA treatment. Functional analysis of DEGGs encoding anabolic enzymes revealed that the process trimming to form core structure and glycan extension from core structure primarily changed, which is consistent with the changes in glycan patterns. In addition, the DEGGs encoding glycoconjugates were mainly related to extracellular matrix and axon guidance. This study provides insights into the underlying molecular mechanism of aberrant glycosylation after prenatal VPA exposure, which may serve as potential biomarkers for the autism diagnosis.
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The activity of the midbrain dopamine system reflects the valence of environmental events and modulates various brain structures to modify an organism's behavior. A series of recent studies reported that the direct and indirect pathways in the striatum are critical for instrumental learning, but the dynamic changes in dopamine neuron activity that occur during negative reinforcement learning are still largely unclear. In the present study, by using a negative reinforcement learning paradigm employing foot shocks as aversive stimuli, bidirectional changes in substantia nigra pars compacta (SNc) dopamine neuron activity in the learning and habituation phases were observed. The results showed that in the learning phase, before mice had mastered the skill of escaping foot shocks, the presence of foot shocks induced a transient reduction in the activity of SNc dopamine neurons; however, in the habituation phase, in which the learned skill was automated, it induced a transient increase. Microinjection of a dopamine D1 receptor (D1R) or D2 receptor (D2R) antagonist into the dorsomedial striatum (DMS) significantly impaired learning behavior, suggesting that the modulatory effects of dopamine on both the direct and indirect pathways are required. Moreover, during the learning phase, excitatory synaptic transmission to DMS D2R-expressing medium spiny neurons (D2-MSNs) was potentiated. However, upon completion of the learning and habituation phases, the synapses onto D1R-expressing medium spiny neurons (D1-MSNs) were potentiated, and those onto D2-MSNs were restored to normal levels. The bidirectional changes in both SNc dopamine neuron activity and DMS synaptic plasticity might be the critical neural correlates for negative reinforcement learning.
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Dopamina/fisiologia , Neurônios Dopaminérgicos/fisiologia , Mesencéfalo/fisiologia , Reforço Psicológico , Animais , Benzazepinas/farmacologia , Corpo Estriado/fisiologia , Antagonistas dos Receptores de Dopamina D2/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Eletrochoque , Vetores Genéticos/administração & dosagem , Vetores Genéticos/farmacologia , Ácido Glutâmico/metabolismo , Habituação Psicofisiológica/efeitos dos fármacos , Habituação Psicofisiológica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/fisiologia , Proteínas Recombinantes/metabolismo , Análise de Célula Única , Sacarose , Transmissão SinápticaRESUMO
Northeast China is the leading grain production region in China where one-fifth of the national grain is produced; however, consistent and reliable crop maps are still unavailable, impeding crop management decisions for regional and national food security. Here, we produced annual 10-m crop maps of the major crops (maize, soybean, and rice) in Northeast China from 2017 to 2019, by using (1) a hierarchical mapping strategy (cropland mapping followed by crop classification), (2) agro-climate zone-specific random forest classifiers, (3) interpolated and smoothed 10-day Sentinel-2 time series data, and (4) optimized features from spectral, temporal, and texture characteristics of the land surface. The resultant maps have high overall accuracies (OA) spanning from 0.81 to 0.86 based on abundant ground truth data. The satellite estimates agreed well with the statistical data for most of the municipalities (R2 ≥ 0.83, p < 0.01). This is the first effort on regional annual crop mapping in China at the 10-m resolution, which permits assessing the performance of the soybean rejuvenation plan and crop rotation practice in China.
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Prolonged stress induces neural maladaptations in the mesolimbic dopamine (DA) system and produces emotional and behavioral disorders. However, the effects of stress on activity of DA neurons are diverse and complex that hinge on the type, duration, intensity, and controllability of stressors. Here, controlling the duration, intensity, and type of the stressors to be identical, we observed the effects of stressor controllability on the activity of substantia nigra pars compacta (SNc) DA neurons in mice. We found that both lack and loss of control (LOC) over shock enhance the basal activity and intrinsic excitability of SNc DA neurons via modulation of Ih current, but not via corticosterone serum level. Moreover, LOC over shock produces more significant enhancement in the basal activity of SNc DA neurons than that produced by shock per se, and therefore attenuates the response to natural reward. This attenuation can be reversed by control over shock. These results indicate that although chronic stress per se tends to enhance the basal activity of SNc DA neurons, LOC over the stressor is able to induce a larger enhancement in the basal activity of SNc DA neurons and produce more severe behavioral deficits. However, control over stress ameliorates the deleterious effects of stress, highlighting the role of stress controllability.
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Neurônios Dopaminérgicos , Parte Compacta da Substância Negra , Animais , Dopamina , Camundongos , RecompensaRESUMO
Maternal vitamin supplementation has been demonstrated to reduce the risks of a number of neurodevelopmental diseases in children. Autism spectrum disorder (ASD) is a group of neurodevelopment defects with high prevalence but without satisfactory therapy. The present work detected the effects of pregnancy supplementation with folic acid (FA) at different doses on rat models of ASD induced by prenatal exposure to valproic acid (VPA), an anti-epileptic increasing the risk of ASD when administered during pregnancy. The results show that maternal FA supplementation at a high dose (4 mg kg-1) prevented the delay in growth and development, and the deficits in social communicative behaviors and repetitive behaviors, possibly by restoring the increased dendritic spine density and rectifying the over-expression of synaptic proteins associated with excitatory neurons and the lower expression with inhibitory ones. The results provided experimental evidence suggesting a possible role of maternal FA supplementation in preventing ASD.
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Transtorno do Espectro Autista/prevenção & controle , Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Ácido Valproico/efeitos adversos , Animais , Transtorno Autístico/induzido quimicamente , Comportamento Animal , Modelos Animais de Doenças , Feminino , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Comportamento SocialRESUMO
Plasticity in the glutamatergic synapses on striatal medium spiny neurons (MSNs) is not only essential for behavioral adaptation but also extremely vulnerable to drugs of abuse. Modulation on these synapses by even a single exposure to an addictive drug may interfere with the plasticity required by behavioral learning and thus produce impairment. In the present work, we found that the negative reinforcement learning, escaping mild foot-shocks by correct nose-poking, was impaired by a single in vivo exposure to 20 mg/kg cocaine 24 h before the learning in mice. Either a single exposure to cocaine or reinforcement learning potentiates the glutamatergic synapses on MSNs expressing the striatal dopamine 1 (D1) receptor (D1-MSNs). However, 24 h after the cocaine exposure, the potentiation required for reinforcement learning was disrupted. Specific manipulation of the activity of striatal D1-MSNs in D1-cre mice demonstrated that activation of these MSNs impaired reinforcement learning in normal D1-cre mice, but inhibition of these neurons reversed the reinforcement learning impairment induced by cocaine. The results suggest that cocaine potentiates the activity of direct pathway neurons in the dorsomedial striatum and this potentiation might disrupt the potentiation produced during and required for reinforcement learning.
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Cocaína , Animais , Cocaína/farmacologia , Corpo Estriado , Neurônios Dopaminérgicos , Camundongos , Camundongos Transgênicos , Reforço PsicológicoRESUMO
Individuals with autism spectrum disorder (ASD) display dysfunction in learning from environmental stimulus that have positive or negative emotional values, posing obstacles to their everyday life. Unfortunately, mechanisms of the dysfunction are still unclear. Although early intervention for ASD victims based on reinforcement learning are commonly used, the mechanisms and characteristics of the improvement are also unknown. By using a mice model of ASD produced by prenatal exposure to valproic acid (VPA), the present work discovered a delayed response-reinforcer forming, and an impaired habit forming in a negative reinforcement learning paradigm in VPA exposure male offspring. But the extinction of the learned skills was found to become faster than normal male animals. Since escape action of nosepoking and the motility remain unchanged in the VPA male offspring, the impaired learning and the accelerated extinction are caused by deficits in higher brain functions underlying association between the animals' behavioral responses and the outcomes of such responses. The results further suggest that the rodent ASD model produced by prenatal exposure to VPA reproduces the deficits in reasoning or building the contingency between one's own behaviors and the consequent outcomes of the behavior seen in ASD patients.
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Transtorno do Espectro Autista/psicologia , Condicionamento Psicológico/fisiologia , Aprendizagem/fisiologia , Animais , Transtorno do Espectro Autista/induzido quimicamente , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Reforço Psicológico , Comportamento Social , Ácido Valproico/efeitos adversosRESUMO
Angiogenesis is induced immediately after cerebral ischemia and plays a pivotal role in the strategy against ischemic injury. We hypothesized that the coordinated interaction between microvessels and neurons was altered immediately after stroke, and microvessels and neurons would show the temporal specificity of angiogenic gene profiles after cerebral ischemia. Microvessels and neurons were harvested in the ischemic penumbra of rat brain using the PixCell II laser capture microdissection (LCM) instrument. After RNA isolation, T7 and gene-specific primer RNA linear amplification were performed, and angiogenic functional grouping cDNA profiling was analyzed in LCM samples. cDNA microarray results showed there were 35 (36.46%) and 27 (28.13%) genes expression changes in the microvessels, while 25 (26.04%) and 31 (32.29%) genes were changed in the neurons at 2 h and 24 h after cerebral ischemia. Members of growth factors and receptors, cytokines and chemokines, adhesion molecules, matrix proteins, proteases, and inhibitors showed temporal and spatial differentiation in the microvessels and neurons after cerebral ischemia. This finding will help to understand the coordination and interaction between microvessels and neurons, and to elucidate the molecular mechanisms of angiogenesis after brain ischemic injury.
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Infarto da Artéria Cerebral Média/metabolismo , Microvasos/metabolismo , Neovascularização Fisiológica/genética , Neurônios/metabolismo , Transcriptoma , Animais , Perfilação da Expressão Gênica , Infarto da Artéria Cerebral Média/patologia , Microdissecção e Captura a Laser , Microvasos/patologia , Neurônios/patologia , Ratos , Ratos Sprague-DawleyRESUMO
The transcriptome sequencing data of valproic acid (VPA) model of autism and control rats are presented. VPA model of autism was induced by a single intraperitoneal injection of 600â¯mg/kg sodium valproic acid to female rats at day 12.5 post-conception, and the control rats were injected with saline. Male offspring of VPA- or saline-injected dams from different litters were sacrificed on PND 35 (n = three rats/three litters/group). Prefrontal cortex was dissected from both hemispheres, and RNA was isolated. Libraries were prepared and RNA Sequencing (RNA-Seq) was performed following Illumina's recommendations. Samples are described in the SRA portal (SRP115258) and FASTQ files have been deposited in Sequence Read Archive (accession numbers: SRR5950172 to SRR5950177). The interpretation of these data is presented in the following research article: "Transcriptional and splicing dysregulation in prefrontal cortex of valproic acid induced rat models of autism" (Zhang et al., 2018) [1].
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Gene-environmental interaction could be the major cause of autism. The aim of the current study is to detect the effects of valproic acid on gene expression profiles and alternatively spliced genes in the prefrontal cortex in rat models of autism. Female rats received a single intraperitoneal injection of 600â¯mg/kg valproic acid at day 12.5 post-conception, and controls were injected with saline. Only male offspring were employed in the current study. RNA sequencing was used to investigate transcriptome in the prefrontal cortex of VPA-exposed rats. There were 3228 differently expressed genes and 637 alternative spliced genes, in VPA rats compared to controls. Pathways enrichment among the differently expressed genes and alternatively spliced genes were associated with neurological diseases and neural system development. The results implied VPA affected transcriptional and splicing events genome-wide and the transcriptional and splicing events may be associated with the autistic behaviors of VPA rats.