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Neuroligin-3 (Nlgn3) is an autism-associated cell-adhesion molecule that interacts with neurexins and is robustly expressed in both neurons and astrocytes. Neuronal Nlgn3 is an essential regulator of synaptic transmission but the function of astrocytic Nlgn3 is largely unknown. Given the high penetrance of Nlgn3 mutations in autism and the emerging role of astrocytes in neuropsychiatric disorders, we here asked whether astrocytic Nlgn3 might shape neural circuit properties in the cerebellum similar to neuronal Nlgn3. Imaging of tagged Nlgn3 protein produced by CRISPR/Cas9-mediated genome editing showed that Nlgn3 is enriched in the cell body but not the fine processes of cerebellar astrocytes (Bergmann glia). Astrocyte-specific knockout of Nlgn3 did not detectably alter the number of synapses, synaptic transmission, or astrocyte morphology in mouse cerebellum. However, spatial transcriptomic analyses revealed a significant shift in gene expression among multiple cerebellar cell types after the deletion of astrocytic Nlgn3. Hence, in contrast to neuronal Nlgn3, astrocytic Nlgn3 in the cerebellum is not involved in shaping synapses but may modulate gene expression in specific brain areas.
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The precise detection of stratum interfaces holds significant importance in geological discontinuity recognition and roadway support optimization. In this study, the model for locating rock interfaces through change point detection was proposed, and a drilling test on composite strength mortar specimens was conducted. With the logistic function and the particle swarm optimization algorithm, the drilling specific energy was modulated to detect the stratum interface. The results indicate that the drilling specific energy after the modulation of the logistic function showed a good anti-interference quality under stable drilling and sensitivity under interface drilling, and its average recognition error was 2.83 mm, which was lower than the error of 6.56 mm before modulation. The particle swarm optimization algorithm facilitated the adaptive matching of drive parameters to drilling data features, yielding a substantial 50.88% decrease in the recognition error rate. This study contributes to enhancing the perception accuracy of stratum interfaces and eliminating the potential danger of roof collapse.
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The safety valves of powered supports control the maximum working resistance, and their statuses must be known to ensure the safety of both the support and the overlying strata. However, the inspection of powered support valves involves manual or semiautomated operations, the costs of which are high. In this study, an extreme point extraction method was developed for the determination of the characteristic parameters of safety valves using roof pressure data, and a safety valve state monitoring module was constructed. Using the longwall face of 0116306 with top coal caving in the Mindong Mine as an example, the characteristic parameters of the safety valves were extracted, including the peak, reseating, and blowdown pressures, as well as the recovery and unloading durations. The results of the field tests showed the following: (1) The amplitude threshold method based on extreme points can be used to accurately extract characteristic parameters, and the distribution of the characteristic parameters of the safety valves follows either a Gaussian or an exponential distribution. (2) The mining pressure analysis results, derived from the characteristic parameters, closely align with the in situ mining pressure observations. This method can be used for the online monitoring of safety valve conditions, increasing the operational efficiency and quality of safety valve inspections.
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The flavoenzyme fructosyl peptide oxidase (FPOX) catalyses the oxidative deglycation of fructosyl amino acids or fructosyl dipeptides to produce amino acids, glucosone and hydrogen peroxide. In this study, FPOX protein from Eupenicillium terrenum sp. (EtFPOX) was expressed in Escherichia coli and purified by Ni-affinity and gel-filtration chromatography. EtFPOX crystals were obtained using the sitting-drop vapour-diffusion method with polyethylene glycol 3350 as precipitant. X-ray diffraction data were collected to 1.90 Å resolution using a synchrotron-radiation source. The crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 65.6, b = 80.0, c = 83.4 Å, and contained one molecule in the asymmetric unit. The calculated Matthews coefficient and solvent content were 2.22 Å(3) Da(-1) and 44.62%, respectively.
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Aminoácido Oxirredutases/biossíntese , Aminoácido Oxirredutases/química , Eupenicillium/enzimologia , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/química , Regulação Fúngica da Expressão Gênica , Aminoácido Oxirredutases/isolamento & purificação , Cristalização , Proteínas Fúngicas/isolamento & purificação , Difração de Raios XRESUMO
High-fat diet (HFD)-induced obesity is a growing epidemic and major health concern. While excessive daytime sleepiness (EDS) is a common symptom of HFD-induced obesity, preliminary findings suggest that reduced wakefulness could be improved with time-restricted feeding (TRF). At present, however, the underlying neural mechanisms remain largely unknown. The paraventricular thalamic nucleus (PVT) plays a role in maintaining wakefulness. We found that chronic HFD impaired the activity of PVT neurons. Notably, inactivation of the PVT was sufficient to reduce and fragment wakefulness during the active phase in lean mice, similar to the sleep-wake alterations observed in obese mice with HFD-induced obesity. On the other hand, enhancing PVT neuronal activity consolidated wakefulness in mice with HFD-induced obesity. We observed that the fragmented wakefulness could be eliminated and reversed by TRF. Furthermore, TRF prevented the HFD-induced disruptions on synaptic transmission in the PVT, in a feeding duration-dependent manner. Collectively, our findings demonstrate that ad libitum access to a HFD results in inactivation of the PVT, which is critical to impaired nocturnal wakefulness and increased sleep, while TRF can prevent and reverse diet-induced PVT dysfunction and excessive sleepiness. We establish a link between TRF and neural activity, through which TRF can potentially serve as a lifestyle intervention against diet/obesity-related EDS.
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Electromagnetic pulse (EMP), a unique type of electromagnetic radiation, may induce diverse neuropsychiatric disorders, such as irritability, hyperkinesis, retardation of learning and memory. However, the underlying mechanism of EMP exposure on neuronal injury has not been elucidated. Here, we aimed to delineate the regulatory expression networks based on high-throughput sequencing data to explore the possible molecular mechanisms related to EMP-induced delirium-like neuropsychiatric disorder in rats. It's shown that EMP exposure induced anxiety, cognitive decline and short-term memory impairment. The expression profiles of the long noncoding RNAs (lncRNAs) and mRNAs, along with their biological function and regulatory network, were explored in rats after EMP exposure. We identified 41 differentially expressed lncRNAs (DELs) and 266 differentially expressed mRNAs (DEMs) between EMP and sham groups. Sixty-one co-expression relationships between 18 DELs and 56 DEMs were mostly associated with synapse- and metabolic-related pathways. We predicted 51 DEL-miRNA pairs and 290 miRNA-mRNA pairs using the miRanda database to constructed a DEL-miRNA-DEM network. LncRNA AABR07042999.1 and mRNA Tph2, Slc6a4, Dbh and Th were upregulated, and the contents of serotonin, dopamine and norepinephrine were increased in both PFC and HIP after EMP exposure. The current study provided a better understanding of the ceRNA network, which might reveal the pathological mechanism and provide more treatment options for the EMP-induced neurobehavioral disorder.
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Delírio , MicroRNAs , RNA Longo não Codificante , Ratos , Animais , RNA Longo não Codificante/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Fenômenos Eletromagnéticos , RNA Mensageiro/genética , Biologia ComputacionalRESUMO
Neuropathic pain is one of the most common symptoms of clinical pain that often accompanied by severe emotional changes such as anxiety. However, the treatment for comorbidity of chronic pain and anxiety is limited. Proanthocyanidins (PACs), a group of polyphenols enriched in plants and foods, have been reported to cause pain-alleviating effects. However, whether and how PACs induce analgesic and anxiolytic effects in the central nervous system remain obscure. In the present study, we observed that microinjection of PACs into the insular cortex (IC) inhibited mechanical and spontaneous pain sensitivity and anxiety-like behaviors in mice with spared nerve injury. Meanwhile, PACs application exclusively reduced the FOS expression in the pyramidal cells but not interneurons in the IC. In vivo electrophysiological recording of the IC further showed that PACS application inhibited the firing rate of spikes of pyramidal cells of IC in neuropathic pain mice. In summary, PACs induce analgesic and anxiolytic effects by inhibiting the spiking of pyramidal cells of the IC in mice with neuropathic pain, which should provide new evidence of PACs as the potential clinical treatment of chronic pain and anxiety comorbidity.
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Empathic pain has attracted the interest of a substantial number of researchers studying the social transfer of pain in the sociological, psychological, and neuroscience fields. However, the neural mechanism of empathic pain remains elusive. Here, we establish a long-term observational pain model in mice and find that glutamatergic projection from the insular cortex (IC) to the basolateral amygdala (BLA) is critical for the formation of observational pain. The selective activation or inhibition of the IC-BLA projection pathway strengthens or weakens the intensity of observational pain, respectively. The synaptic molecules are screened, and the upregulated synaptotagmin-2 and RIM3 are identified as key signals in controlling the increased synaptic glutamate transmission from the IC to the BLA. Together, these results reveal the molecular and synaptic mechanisms of a previously unidentified neural pathway that regulates observational pain in mice.
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Complexo Nuclear Basolateral da Amígdala , Animais , Complexo Nuclear Basolateral da Amígdala/fisiologia , Córtex Cerebral/fisiologia , Ácido Glutâmico/fisiologia , Córtex Insular , Camundongos , Dor , SinapsesRESUMO
Deep coal cutting is a hot research topic at present. In this paper, the cutting technology of three-drum shearer was proposed based on previous studies. Besides, the influence of confining pressure on coal cutting performance was studied by using the discrete element method, and the induction effect of central cutting on coal cutting performance was discussed. Moreover, coal cutting with different boundary conditions was simulated with the aid of PFC2D software. The results show that as the confining pressure increases, the model dominated by tensile failure does not change, but the crack gradually develops from the vertical direction to the free surface of coal. The cutting debris first increases and then decreases; so does the cutting force. Under the effect of central cutting, the crack tends to develop towards the free surface of coal more, and both the peak cutting force and the specific energy consumption increase with the increase of confining pressure. Induced by central cutting, with the increase of confining pressure, the reduction value of peak cutting force increases first and then decreases while the reduction value of cutting specific energy consumption increases.
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The FAOD/FPOD family of proteins has the potential to be useful for the longterm detection of blood glucose levels in diabetes patients. A bottleneck for this application is to find or engineer a FAOD/FPOD family enzyme that is specifically active towards α-fructosyl peptides but is inactive towards other types of glycated peptides. Here, the crystal structure of fructosyl peptide oxidase from Eupenicillium terrenum (EtFPOX) is reported at 1.9â Å resolution. In contrast to the previously reported structure of amadoriase II, EtFPOX has an open substrate entrance to accommodate the large peptide substrate. The functions of residues critical for substrate selection are discussed based on structure comparison and sequence alignment. This study reveals the first structural details of group I FPODs that prefer α-fructosyl substrates and could provide significant useful information for uncovering the mechanism of substrate specificity of FAOD/FPODs and guidance towards future enzyme engineering for diagnostic purposes.
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Aminoácido Oxirredutases/química , Aminoácido Oxirredutases/metabolismo , Eupenicillium/enzimologia , Aminoácido Oxirredutases/genética , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Especificidade por Substrato/fisiologiaRESUMO
The experiment was conducted by directed evolution strategy (error-prone PCR) to improve the activity of aflatoxin detoxifzyme with the high-throughput horse radish peroxidas and recessive brilliant green (HRP-RBG) screening system. We built up a mutant library to the order of 10(4). Two rounds of EP-PCR and HRP-RBG screening were used to obtain three optimum mutant strains A1773, A1476 and A2863. We found that mutant A1773 had upper temperature tolerance of 70 degrees C and that its enzyme activity was 6.5 times higher than that of the parent strain. Mutant strains A1476 worked well at pH 4.0 and its enzyme activity was 21 times higher than that of the parent strain. Mutant A2863 worked well at pH 4.0 and pH 7.5, and its enzyme activity was 12.6 times higher than that of the parent strain. With DNA sequencing we found that mutant A1773 revealed two amino acid substitutions, Glu127Lys and Gln613Arg. Mutant A1476 revealed four amino acid substitutions: Ser46Pro, Lys221Gln, Ile307Leu and Asn471lle. Mutant A2863 revealed four amino acid substitutions: Gly73Ser, Ile307Leu, Va1596Ala and Gln613Arg. The results provided a useful illustration for the deep understanding of the relationship between the function and structure of aflatoxin detoxifzyme.