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Exosomes can penetrate the blood-brain barrier for material exchange between the peripheral and central nervous systems. Differences in exosome contents could explain the susceptibility of different individuals to depression-like behavior after traumatic spinal cord injury (TSCI). Hierarchical clustering was used to integrate multiple depression-related behavioral outcomes in sham and TSCI rats and ultimately identify non-depressed and depressed rats. The difference in plasma exosome contents between non-depressed and depressed rats after TSCI was assessed in 15 random subjects by performing plasma exosome transcriptomics, mass spectroscope-based proteomics, and non-targeted metabolomics analyses. The results revealed that about 27.6% of the rats developed depression-like behavior after TSCI. Totally, 10 differential metabolites, 81 differentially expressed proteins (DEPs), 373 differentially expressed genes (DEGs), and 55 differentially expressed miRNAs (DEmiRNAs) were identified between non-depressed TSCI and sham rats. Meanwhile, 37 differential metabolites, 499 DEPs, 1361 DEGs, and 89 DEmiRNAs were identified between depressed and non-depressed TSCI rats. Enrichment analysis showed that the progression of depression-like behavior after TSCI may be related to amino acid metabolism disorder and dysfunction of multiple signaling pathways, including endocytosis, lipid and atherosclerosis, toll−like receptor, TNF, and PI3K-Akt pathway. Overall, our study systematically revealed for the first time the differences in plasma exosome contents between non-depressed and depressed rats after TSCI, which will help broaden our understanding of the complex molecular mechanisms involved in brain functional recombination after TSCI. • Different rats have different susceptibility to depression after TSCI. • The plasma exosome contents of depression-susceptible and resilient rats markedly differ at multiple omics level. • Endocytosis, lipid and atherosclerosis, toll−like receptor, TNF, and PI3K-Akt pathway may be related to depression after TSCI. [ABSTRACT FROM AUTHOR]

Depression induced by spinal cord injury (SCI) has been demonstrated in clinical and experimental studies; it significantly impacts patients' lives and may be associated with changes in the hippocampus. However, the biological mechanisms underlying depression after SCI are unknown. The mitogen-activated protein kinase (MAPK) signaling pathway participates in potential mechanisms of depression; it is unknown whether this pathway plays a role in SCI-induced depression. We applied an animal model of depression induced by SCI, established using an aneurysm clip, to determine whether MAPK activation in the hippocampus is associated with depression-like behavior. SCI led to depression-like behavior, such as anhedonia in the sucrose preference test, decreased number of crossings in the open field test, decreased body weight, and decreased immobility time in the forced swim test. Western blot analysis further showed that SCI significantly increased the levels of phosphorylated p38 MAPK and cleaved caspase-3 in the hippocampus and inhibited the phosphorylation of extracellular signal-related kinase 1/2 and c-Jun N-terminal kinase 1/2. In addition, there were significant negative correlations between depression-like behavior and phosphorylated extracellular signal-related kinase 1/2 and positive correlations between depression-like behavior and phosphorylated p38 MAPK and cleaved caspase-3. These findings suggest that the MAPK pathway in the rat hippocampus may be involved in the pathophysiology of depression induced by SCI. [ABSTRACT FROM AUTHOR]

Spinal cord injuries (SCIs) are difficult to treat. The first animal SCI model (featuring the dropping of a weight) was established by Allen in 1911, and other animal models have been developed since then. Most animal studies have focused only on the molecular features of SCIs, which remain disputed. Recently, it has become clear that SCI may trigger mental and cognitive disorders, however, and brain changes secondary to SCI are under investigation. No consensus on an optimal animal model for cerebral research has emerged. We discuss the appropriate SCI models for studying secondary brain changes. [ABSTRACT FROM AUTHOR]

Due to high efficiency, energy saving, environmental friendliness and safety, the air source heat pump (ASHP) has drawn much attention in the cold and serve cold climate areas of China. In recent years, the Chinese governments further promote the application of air source heat pump in the cold and server area in order to reduce conventional energy consumption and haze occurrence frequency in heating season. The outdoor air temperature is low and fluctuates greatly in these areas, which might lead to unstable running, low efficiency and frequent frost. In this paper, the development direction of ASHP in cold and serve cold was pointed out by analyzing the existing problems of air source heat pump under low temperature condition. These results could provide some references for promotion and application of ASHP in cold and serve cold area like Qinghai province. [ABSTRACT FROM AUTHOR]

• BDNF in the spinal dorsal horn are closely connected with neuropathic pain. • In physiological conditions, BDNF is an important regulator of neuronal development, synaptic transmission, and cellular and synaptic plasticity. • In pathological conditions, BDNF in the spinal dorsal horn may change the CNS from an adaptive state to an unadaptive state. • Elucidate the mechanism of BDNF in spinal dorsal horn and neuropathic pain. Neuropathic pain (NP) is caused by direct or indirect damage to the nervous system and is a common symptom of many diseases. The mechanisms underlying the onset and persistence of NP are unclear. Therefore, research concerning these mechanisms has become an important focus in the medical field. Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophic factor family of signaling molecules. BDNF is an important regulator of neuronal development, synaptic transmission, and cellular and synaptic plasticity, which are essential for nerve maintenance and repair. However, BDNF is upregulated in the spinal dorsal horn and can promote NP by activating glial cells, reducing inhibitory functions and enhancing excitement after nociceptive stimulation. This review considers the relationship between NP and BDNF signaling in the spinal dorsal horn and discusses potentially related pathological mechanisms. [ABSTRACT FROM AUTHOR]

Ferroptosis is involved in traumatic spinal cord injury (SCI), and its inhibition may improve functional recovery after traumatic SCI. This study investigated whether metformin (Met) can have a neuroprotective effect in SCI repair by inhibiting ferroptosis. We assessed functional change to determine the long-term effects after intraperitoneal injection of Met in SCI rats with the Basso–Beattie–Bresnahan locomotor rating scale. Malondialdehyde level and relative expression of key proteins, inflammatory cytokines, and nuclear factor E2-related factor 2 signalling molecules were determined in SCI rats and PC12 cells exposed to FeCl 3 solution. Met treatment decreased the contents of malondialdehyde, regulated the levels of inflammatory factors, activated the nuclear factor E2-related factor 2 signalling pathway, and improved long-term outcomes by ameliorating SCI-induced locomotor deficits. In vitro studies further confirmed the beneficial and antiferroptotic actions of Met partly through activation of nuclear factor E2-related factor 2 signalling. Met can have a neuroprotective effect on SCI repair partly through antiferroptotic effects. [ABSTRACT FROM AUTHOR]

Neuroinflammation is an important secondary aggravating factor in spinal cord injury (SCI). Inhibition of the inflammatory response is critical for SCI treatment. Glycyrrhizic acid (GA) is an anti-inflammatory drug, but its utility for SCI is unclear. This study aimed to evaluate the effects of GA on inflammation after SCI and the underlying mechanism. Cell counting kit-8 assays were performed to assess the viability of highly aggressively proliferating immortalized cells that had been treated with lipopolysaccharide (LPS) and/or GA. Reverse transcription quantitative polymerase chain reaction and Western blotting were performed to assess expression of high mobility group box-1 protein (HMGB1), ionized calcium binding adaptor molecule 1, and inflammatory factors in vitro and in vivo. GA (100 mg/kg) was intraperitoneally injected into rats. Anti-inflammatory effects of GA were analyzed in SCI tissues. p38/Jun N-terminal kinase signaling pathway proteins were analyzed by Western blotting. Cell counting kit-8 assay results showed that treatment with 100 ng/mL LPS for 12 hours was optimal. After LPS treatment, highly aggressively proliferating immortalized cells were activated; messenger RNA expression levels of HMGB1 and inflammatory factors were increased. GA significantly inhibited LPS-induced HMGB1 expression and inflammatory responses, as determined by reverse transcription quantitative polymerase chain reaction and Western blotting. Transfection with an HMGB1-overexpression plasmid reversed the anti-inflammatory effects of GA. In addition, intraperitoneal injection of GA (100 mg/kg) into rats for 3 days significantly reduced expression levels of HMGB1 and inflammatory factors after SCI in vivo. GA reduced phosphorylation, but not levels, of p38 and Jun N-terminal kinase proteins. GA attenuates the inflammatory response after SCI by inhibiting HMGB1 through the p38/JNK signaling pathway and thus has therapeutic potential for SCI. [ABSTRACT FROM AUTHOR]

Contralateral subdural effusion (CSE) after decompressive craniectomy (CSEDC) is occasionally observed. Cranioplasty is routinely performed for reconstruction and has recently been associated with improving contralateral subdural effusion. We sought to systematically review all available literature and evaluate the effectiveness of cranioplasty for CSE. A PubMed, Web of Science, and Google Scholar search was conducted for preferred reporting items following the guidelines of systematic review and meta-analysis, including studies reporting patients who underwent cranioplasty because of CSEDC. The search yielded 8 articles. A total of 56 patients ranging in age from 21 to 71 years developed CSEDC. Of them, 32 patients underwent cranioplasty. Eighteen cases with symptomatic CSE underwent cranioplasty alone, 2 cases received Ommaya drainage later because of a recurrence of CDC, and 1 case underwent a ventriculoperitoneal shunt because the CSE did not resolve completely and the ventricle was dilated again. The symptoms of 14 cases lessened without recurrence after simultaneous cranioplasty and drainage or a shunt. The total success rate (CSE disappeared without recurrence) was 90.6% for patients who underwent cranioplasty; however, the total incidence of hydrocephalus was 40.1%. This review suggests that cranioplasty is effective for the treatment of CSEDC, particularly intractable cases, but early cranioplasty may be more effective. In addition, hydrocephalus is fairly common after cranioplasty and requires further treatment. [ABSTRACT FROM AUTHOR]

• A novel immobilization strategy based on AuNPs/PB-ZIF-8@SWCNT was first developed. • The combination of ZIF-8@SWCNT and AuNPs/PB enhanced the sensor performance. • A low detection limit of 10−16 M was achieved at the olfactory biosensor. • The sensor exhibited a long storage stability of 15 days. Hexanal is considered as an important volatile compound indicator for the assessment of freshness and maturity of foods. Therefore, sensitive and stable monitoring of hexanal is highly desired. Herein, an efficient receptor immobilization strategy based on ZIF-8@ Single-walled carbon nanotube (SWCNT) and nanosomes-AuNPs/Prussian blue (PB) was proposed for the development of olfactory biosensors. ZIF-8@SWCNT as dual support materials provided a high density of active sites for nanosomes loading. Moreover, the co-electrodeposition of nanosomes-AuNPs and PB on the sensor interface effectively amplified the electrochemical signal and maintained the activity of the receptor. The combination of ZIF-8@SWCNT with AuNPs/PB imparts excellent sensing performance of the biosensor with a wide detection range of 10−16–10−9 M, a low detection limit of 10−16 M for hexanal, and a long storage stability of 15 days. These results indicate that our biosensor can be a powerful tool for versatile applications in food and other related industries. [ABSTRACT FROM AUTHOR]

Neuroimaging studies have shown that spinal cord injury (SCI) may lead to significant brain changes that are the key factors affecting functional recovery. However, little is known about the molecular and cellular biological mechanisms of these brain changes. The aim of this study was to investigate the molecular and cellular biological changes in the cerebellum after SCI. A total of 72 mice were randomly divided into 2 groups: sham group and SCI group. A mouse model of SCI was established by an aneurysm clip. Pathological examinations of the injured site were performed by hematoxylin and eosin staining and immunohistochemical. Western blot and immunohistochemical were used to determine the effect of SCI on the differentiation and maturation of NG2 cells. Compared with the sham group, the spinal cord tissue structure was disrupted and the motor function decreased significantly in the SCI group; the number of NG2 cells in the ansiform lobule crus Ⅰ increased on the 7th and 14th days, whereas the expression of oligodendrocyte transcription factor 2, myelin basic protein, and proteolipid protein decreased on the 7th and 14th days after SCI. These results showed that the differentiation and maturation of NG2 cells in the ansiform lobule crus Ⅰ were inhibited after SCI, resulting in the decrease of the formation of mature oligodendrocytes. These results indicate that SCI can lead to secondary changes in the cerebellum, which may affect the functional recovery. These findings may be used as biomarkers to evaluate the secondary changes in the brain after SCI. [ABSTRACT FROM AUTHOR]

This study aims to described the epidemiology and genotypic diversity of Human metapneumovirus (HMPV) and the impact of SARS-CoV-2 on the prevalence of HMPV in hospitalized children with Acute respiratory tract infections (ARTIs) in Beijing, China. From April 2018 to March 2019 and from September 2020 to August 2021, nasopharyngeal aspirates (NPAs) from hospitalized children with ARTIs in Beijing were collected and subjected to real-time polymerase chain reaction tests for HMPV. Then genotyping, detection of 15 common respiratory viruses and clinical characteristics were analyzed on HMPV positive samples. 7.9% (124/1572) enrolled pediatric patients were identified as having HMPV infection, and the majority of children under the age of 5 (78.2%, 92/124), From April 2018 to March 2019. The detection rate of HMPV in spring and winter is significantly higher than that in summer and autumn. The co-infection rate were 37.1% (46/124), the most common co-infected virus were parainfluenza virus type 3 (HPIV-3). The main diagnosis of HMPV infection was pneumonia (92.7%,115/124), most patient have cough and fever. Of 78 HMPV-positive specimens, A2b (82.1%,64/78) were the main epidemic subtypes. Hospitalized children with HMPV genotype A infection had a higher viral load compared to genotype B. During the COVID-19 outbreak, Among 232 samples, only 4 cases were HMPV-positive. After statistical test, the detection rate of HMPV during the COVID-19 pandemic has decreased significantly compared with that before the epidemic (p = 0.001). HMPV is an important cause of ARTIs in children under 5 years old. The epidemic peak is generally in winter and spring, and the A2b subtype is the most common. However, under the prevention and control of the COVID-19 pandemic, the HMPV infection of hospitalized children with ARTIs has decreased significantly. • The epidemic peak of HMPV is generally in winter and spring. • HMPV A2b subtype is the most common in Beijing, China. • The main circulating strain of HMPV infection in Beijing in 2017–2019 switched from B1 subtype to A2b subtype. • The HMPV infection of hospitalized children with ARTIs has decreased significantly during COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Summary Elongator is a highly conserved multiprotein complex composed of six subunits (Elp1–6). Elongator has been associated with various cellular activities and has attracted clinical attention because of its role in certain neurodegenerative diseases. Here, we present the crystal structure of the Elp2 subunit revealing two seven-bladed WD40 β propellers, and show by structure-guided mutational analyses that the WD40 fold integrity of Elp2 is necessary for its binding to Elp1 and Elp3 subunits in multiple species. The detailed biochemical experiments indicate that Elp2 binds microtubules through its conserved alkaline residues in vitro and in vivo. We find that both the mutually independent Elp2-mediated Elongator assembly and the cytoskeleton association are important for yeast viability. In addition, mutation of Elp2 greatly affects the histone H3 acetylation activity of Elongator in vivo. Our results indicate that Elp2 is a necessary component for functional Elongator and acts as a hub in the formation of various complexes. [ABSTRACT FROM AUTHOR]