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One of the core symptoms of autism spectrum disorder (ASD) is impaired social interaction. Currently, no pharmacotherapies exist for this symptom due to complex biological underpinnings and distinct genetic models which fail to represent the broad disease spectrum. One convincing hypothesis explaining social deficits in human ASD patients is amotivation, however it is unknown whether mouse models of ASD represent this condition. Here we used two highly trusted ASD mouse models (male Shank3‐deficient [Shank3+/ΔC] mice modeling the monogenic etiology of ASD, and inbred BTBR mice [both male and female] modeling the idiopathic and highly polygenic pathology for ASD) to evaluate the level of motivation to engage in a social interaction. In the behavioral paradigms utilized, a social stimulus was placed in the open arm of the elevated plus maze (EPM), or the light compartment of the light‐dark box (LDB). To engage in a social interaction, mice were thus required to endure innately aversive conditions (open areas, height, and/or light). In the modified EPM paradigm, both Shank3+/ΔC and BTBR mice demonstrated decreased open‐arm engagement with a social stimulus but not a novel object, suggesting reduced incentive to engage in a social interaction in these models. However, these deficits were not expressed under the less severe aversive pressures of the LDB. Collectively, we show that ASD mouse models exhibit diminished social interaction incentive, and provide a new investigation strategy facilitating the study of the neurobiological mechanisms underlying social reward and motivation deficits in neuropsychiatric disorders.  相似文献   
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Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM‐induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM‐induced expression of α‐smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor‐β1, interleukin‐1β, and tumor necrosis factor‐α in the lungs of BLM‐stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM‐induced murine model.  相似文献   
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具有多重耐药性和广泛耐药性的结核分枝杆菌菌株正在全球范围内传播,因此,迫切需要新的抗结核药物。结核分枝杆菌的L,D-转肽酶LdtMt2直接参与肽聚糖的形成,细菌毒性和β-内酰胺抗性。该酶是潜在的抗结核靶标,可以被碳青霉烯类抗生素抑制,碳青霉烯类抗生素是FDA批准的用于治疗肺结核的药物。据报道,LdtMt2与碳青霉烯类抗生素(如厄他培南,亚胺培南和美洛培南)相互作用时,存在两种不同的中间状态,即状态I和II。状态I被认为是初始加合物形成状态,而状态II被认为是稳定的蛋白质-配体相互作用状态,并伴有碳青霉烯类抗生素和蛋白质的局部构象排列。本文中,我们报告了一个LdMt2-ertapenem新中间状态I-plus,具有与状态II相同的碳青霉烯类抗生素构象和与状态I相似的局部蛋白质构象。该新状态是从状态I转变为状态II的中间状态,构象变化发生在厄他培南分子而不是蛋白质。我们的工作有助于阐明碳青霉烯类抗生素对LdtMt2的作用后发生的变化,并与其他报道的中间状态一起揭示L,D-转肽酶如何与碳青霉烯类抗生素相互作用。  相似文献   
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Zhang  Xinheng  Chen  Tong  Chen  Sheng  Nie  Yu  Xie  Zi  Feng  Keyu  Zhang  Huanmin  Xie  Qingmei 《中国病毒学》2021,36(6):1431-1442
Virologica Sinica - Infectious bronchitis (IB) is a highly contagious avian disease caused by infection with infectious bronchitis virus (IBV), which seriously affects the development of the global...  相似文献   
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A notable advantage of zebrafish as a model organism is the ease of gene knockdown using morpholino antisense oligonucleotide (MO). However, zebrafish morphants injected with MO for a target protein often show heterogeneous phenotypes, despite controlling the injection volume of the MO solution in all embryos. We developed a method for estimating the quantity of MO injected into each living morphant, based on the co-injection of a control MO labeled with the fluorophore lissamine. By applying this method for knockdown of cardiac troponin T (tnnt2a) in zebrafish, we could efficiently select the partial tnnt2a-depleted zebrafish with a decreased heart rate and impairment of cardiac contraction. To investigate cardiac impairment of the tnnt2a morphant, we performed fluorescent cardiac imaging using Bodipy-ceramide. Cardiac image analysis showed moderate reduction of tnnt2a impaired diastolic distensibility and decreased contraction and relaxation velocities. To the best of our knowledge, this is the first report to analyze the role of tnnt2a in cardiac function in tnnt2a-depleted living animals. Our combinatorial approach can be applied for analyzing the molecular function of any protein associated with human cardiac diseases.  相似文献   
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Earlier studies on fructose laurate ester products have shown that recombinant Pichia pastoris displaying Candida antarctica lipase B (CALB) on the cell surface acts as an efficient whole-cell biocatalyst for sugar ester production from fructose and lauric acid in an organic solvent. The effects of various reaction factors, including solvent composition, substrate molar ratio, enzyme dose, temperature and water activity, on esterification catalyzed by the CALB-displaying P. pastoris whole-cell biocatalyst were examined in the present study. Under the preferred reaction conditions, specifically, 5 mL organic solvent mixture of 2-methyl-2-butanol/DMSO (20% v/v), 2 mmol fructose with a lauric acid to fructose molar ratio of 2:1, 0.3 g whole-cell biocatalyst (1,264 U/g dry cell) with an initial water activity of 0.11, 1.2 g 4Å molecular sieve, reaction temperature of 55oC and 200 rpm stirring speed, the fructose mono laurate ester yield was 78% (w/w). The CALBdisplaying P. pastoris whole-cell biocatalyst exhibited good operational stability, with an evident increase, rather than decrease, in relative activity after the continuous recover and reuse cycle. The relative activity of the biocatalyst remained 50% higher than that of the first batch, even following reuse for 15 batches. Our results collectively indicate that the CALB-displaying P. pastoris whole-cell biocatalyst may be potentially utilized in lieu of free or immobilized enzyme to effectively produce non-ionic surfactants such as fatty acid sugar esters, offering the significant advantages of cost-effectiveness, good operational stability and mild reaction conditions.

  相似文献   
20.

Background

Insulin resistance (IR) triggers endothelial dysfunction, which contributes to erectile dysfunction (ED) and cardiovascular disease.

Aim

To evaluate whether IR was related to ED in young adult patients.

Methods

A total of 283 consecutive men complaining of ED at least six months were enrolled, with a full medical history, physical examination, and laboratory tests collected. Quantitative Insulin Sensitivity Check Index (QUICKI) was used to determine IR. The severity of ED was assessed by IIEF-5 questionnaire. Endothelial function was assessed by ultrasonographic examination of brachial artery flow mediated dilation (FMD).

Results

IR was detected in 52% patients. Subjects with IR had significant higher total cholesterol, triglycerides, low density lipoprotein-cholesterol (LDL-c), glycated haemoglobin (HBA1c), high sensitivity C-reactive protein (hs-CRP) and body mass index (BMI), but showed significant lower IIEF-5 score, FMD%, high density lipoprotein -cholesterol (HDL-c), testosterone, sex hormone binding globulin (SHBG) levels than patients without IR. Multiple regression analysis showed QUICKI and testosterone were independent predictors of IIEF-5 score. Furthermore, the incidence of IR was correlated with the severity of ED.

Conclusions

Compared with other CVFs, IR was found as the most prevalent in our subjects. Besides, IR was independently associated with ED and its severity, suggesting an adverse effect of insulin resistance on erectile function.  相似文献   
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