57 research outputs found

    Left Anterior Temporal Lobe and Bilateral Anterior Cingulate Cortex Are Semantic Hub Regions: Evidence from Behavior-Nodal Degree Mapping in Brain-Damaged Patients

    Get PDF
    The organizational principles of semantic memory in the human brain are still controversial. Although studies have shown that the semantic system contains hub regions that bind information from different sensorimotoric modalities to form concepts, it is unknown whether there are hub regions other than the anterior temporal lobe (ATL). Meanwhile, previous studies have rarely used network measurements to explore the hubs or correlated network indexes with semantic performance, although the most direct supportive evidence of hubs should come from the network perspective. To fill this gap, we correlated the brain-network index with semantic performance in 86 brain-damaged patients. We especially selected the nodal degree measure that reflects how well a node is connected in the network. The measure was calculated as the total number of connections of a given node with other nodes in the resting-state functional MRI network. Semantic ability was measured using the performance of both general and modality-specific (object form, color, motion, sound, manipulation, and function) semantic tasks. We found that the left ATL and the bilateral anterior cingulate cortex could be semantic hubs because the reduced nodal degree values of these regions could effectively predict the deficits in both general and modality-specific semantic performance. Moreover, the effects remained when the analyses were performed only in the patients who did not have lesions in these regions. The two hub regions might support semantic representations and executive control processes, respectively. These data provide empirical evidence for the distributed-plus-hub theory of semantic memory from the network perspective.</p

    Undiagnosed diabetic retinopathy in Northeast China: prevalence and determinants

    Get PDF
    ObjectiveTo report the prevalence and contributing factors of undiagnosed diabetic retinopathy (DR) in a population from Northeastern China.Subjects/MethodsA total of 800 subjects from the Fushun Diabetic Retinopathy Cohort Study were enrolled. A questionnaire assessing incentives and barriers to diagnosis of DR was administered. Logistic regression was used to identify clinical and sociodemographic factors associated with undiagnosed DR. In a prespecified subgroup analysis, we divided patients into vision-threatening diabetic retinopathy (VTDR) and non-VTDR (NVTDR) subgroups.ResultsAmong 800 participants with DR, 712 (89.0%) were undiagnosed. Among 601 with NVTDR, 566 (94.2%) were undiagnosed. Among 199 with VTDR, 146 (73.4%) were undiagnosed. The risk factors affecting the timely diagnosis of NVTDR and VTDR exhibit significant disparities. In multivariate models, factors associated with undiagnosed VTDR were age over 60 years (OR = 2.966; 95% CI = 1.205-7.299; P = 0.018), duration of diabetes over 10 years (OR = 0.299; 95% CI = 0.118-0753; P = 0.010), visual impairment or blindness (OR = 0.310; 95% CI = 0.117-0.820; P = 0.018), receiving a reminder to schedule an eye examination (OR = 0.380; 95% CI = 0.163-0.883; P = 0.025), and the belief that “people with diabetes are unlikely to develop an eye disease” (OR = 4.691; 95% CI = 1.116-19.724; P = 0.035). However, none of the factors were associated with undiagnosed NVTDR (all P ≥ 0.145).ConclusionOur research has uncovered a disconcerting trend of underdiagnosis in cases of DR within our population. Addressing determinants of undiagnosed DR may facilitate early detection

    RPS23RG1 modulates tau phosphorylation and axon outgrowth through regulating p35 proteasomal degradation

    Get PDF
    Tau蛋白病(Tauopathies)是由过度磷酸化的tau蛋白聚集形成神经纤维缠结为特征的一类神经退行性疾病,包括阿尔茨海默病(Alzheimer’s disease, AD)、进行性核上性麻痹(Progressive superanuclear palsy, PSP)、额颞叶痴呆(Frontotemporal dementia, FTD)等。随着全球社会结构的老龄化,tau蛋白病患者比率迅速增加,给个人和社会带来巨大的经济及精神负担。厦门大学神经科学研究所张云武教授团队最新发现RPS23RG1(RR1)的胞内羧基端区域能够与Cdk5激酶的激活蛋白p35的氨基端相互作用,介导p35的膜定位并影响其泛素化降解,从而调控在tau蛋白异常磷酸化过程中发挥重要作用的Cdk5激酶的活性。团队研究表明RPS23RG1通过其胞内羧基端与p35相互作用,介导p35膜结合和降解,从而抑制Cdk5活性,平衡tau磷酸化水平,促进轴突生长。此外,RPS23RG1的跨膜区与腺苷酸环化酶AC相互作用,抑制GSK3-β活性,同样控制tau过度磷酸化。提示RPS23RG1是改善tau过度磷酸化水平及治疗tau蛋白病的潜在靶点。 厦门大学医学院神经科学研究所博士后赵东栋为该研究第一作者,张云武教授为通讯作者。【Abstract】Tauopathies are a group of neurodegenerative diseases characterized by hyperphosphorylation of the microtubule-binding protein, tau, and typically feature axon impairment and synaptic dysfunction. Cyclin-dependent kinase5 (Cdk5) is a major tau kinase and its activity requires p35 or p25 regulatory subunits. P35 is subjected to rapid proteasomal degradation in its membrane-bound form and is cleaved by calpain under stress to a stable p25 form, leading to aberrant Cdk5 activation and tau hyperphosphorylation. The type Ib transmembrane protein RPS23RG1 has been implicated in Alzheimer’s disease (AD). However, physiological and pathological roles for RPS23RG1 in AD and other tauopathies are largely unclear. Herein, we observed retarded axon outgrowth, elevated p35 and p25 protein levels, and increased tau phosphorylation at major Cdk5 phosphorylation sites in Rps23rg1 knockout (KO) mice. Both downregulation of p35 and the Cdk5 inhibitor roscovitine attenuated tau hyperphosphorylation and axon outgrowth impairment in Rps23rg1 KO neurons. Interestingly, interactions between the RPS23RG1 carboxyl-terminus and p35 amino-terminus promoted p35 membrane distribution and proteasomal degradation. Moreover, P301L tau transgenic (Tg) mice showed increased tau hyperphosphorylation with reduced RPS23RG1 levels and impaired axon outgrowth. Overexpression of RPS23RG1 markedly attenuated tau hyperphosphorylation and axon outgrowth defects in P301L tau Tg neurons. Our results demonstrate the involvement of RPS23RG1 in tauopathy disorders, and implicate a role for RPS23RG1 in inhibiting tau hyperphosphorylation through homeostatic p35 degradation and suppression of Cdk5 activation. Reduced RPS23RG1 levels in tauopathy trigger aberrant Cdk5-p35 activation, consequent tau hyperphosphorylation, and axon outgrowth impairment, suggesting that RPS23RG1 may be a potential therapeutic target in tauopathy disorders.This work was supported by grants from National Key Research and Development Program of China (2016YFC1305903 and 2018YFC2000400 to Y-wZ), National Natural Science Foundation of China (81771377, U1705285, 91332112, and 81225008 to Y-wZ), Fundamental Research Funds for the Central Universities (20720180049 to Y-wZ), the Fujian Provincial Health Commission-Education Department Joint Tackling Plan (WKJ2016-2-18 to F-rL), and Postdoctoral Science Foundation of China (2020M671948 to DZ)

    Collaborative Optimization of Emissions and Abatement Costs for Air Pollutants and Greenhouse Gases from the Perspective of Energy Structure: An Empirical Analysis in Tianjin

    No full text
    Both air pollution and greenhouse effect have become important issues with regard to environmental protection both in China and across the world. Consumption of energy derived from coal, oil, and natural gas forms the main source of China&rsquo;s major air pollutants, SO2 and NOX, as well as the major greenhouse gas CO2. The energy structure adjustment approach provides a sensible way, not only to achieve climate change mitigation and air pollutant reduction, but also to reduce abatement costs. In this paper, a multi-objective optimization method was adopted in order to analyze the collaborative optimization of emissions and abatement costs for both air pollutants and greenhouse gases. As a typical industrial city and economic center with fossil fuels as its main energy source, Tianjin of China is used as the research sample to prove that this method can mitigate air pollutants and greenhouse gas emissions and reduce abatement costs. Through demonstration, the results show that the optimization method proposed can reduce SO2, NOX, and CO2 emissions by 27,000 tons, 33,000 tons, and 29,000 tons, respectively, and the abatement costs will be reduced by 620 million yuan by adjusting the energy structure of Tianjin. The proposed method also suggests that China can achieve reductions of abatement cost and greenhouse gas and air pollutant emissions under the proposed energy structure. The results indicate that collaborative optimization would help China and other countries cope with climate change while improving domestic air quality

    Properties Exploring and Information Mining in Consumer Community Network: A Case of Huawei Pollen Club

    No full text
    Substantial changes took place in the role of consumers in the supply chain with the development of practices. They became creators from consumers of product values. More and more consumers express their consumption experiences by posting in network community. Consumer community network is an important place for feedback of product experiences and facilitating product innovation in future. Manufacturers can promote improvement and innovation of products by exploring effective information on the consumer community network, thus improving the experience level of consumers. Therefore, how to explore information in topics (posts) and their relationships becomes very important. Is it possible to describe the structure of consumer community network by complex network and explore information about products and consumers? There is important and positive significance to study the collaborative innovation in the supply chain in which consumers participate. In this paper, the consumer community network was constructed by Boolean retrieve programming and discussed in the methodology and empirical way based on the community data of Huawei P10/P10 Plus. In methodology, interaction difference and uniformity within consumer community were explored by the density of isolated nodes and generalized variance of degree of network. In empirical studies, community network users were divided into ordinary user group, intermediary user group, and enterprise user group according to empirical data, and corresponding interaction networks were constructed. A contrastive analysis on the interaction of these three groups was carried out by combining the existing properties and innovative properties. Topics in each network were put in the order according to significance. Research conclusions have important significance to enrich the network analysis methods, explore the effective information in consumer community network, facilitate product improvement and innovations, and improve the experience level of consumers

    <p>PEO-based CO2-philic mixed matrix membranes compromising N-rich ultramicroporous polyaminals for superior CO2 capture</p>

    No full text
    Polymer molecular sieve materials (PMS) are promising porous fillers that can be used to fabricate highperformance gas separation mixed matrix membranes (MMMs) to overcome the inherent trade-off. In this work, a nitrogen-rich ultramicroporous (0.34 nm, 0.50 nm) polyaminal network (PAN-NH2) was introduced into crosslinked PEO polymer to prepare CO2-philic MMMs with superior CO2 capture performance. Due to the synergistical interaction of the dipole-quadrupole and molecular sieving effect, PAN-NH2 demonstrates excellent molecular recognition of CO2. PAN-NH2 can be well dispersed in polymer matrix to achieve good polymer-filler interface compatibility. The incorporation of PAN-NH2 significantly improves the CO2 permeability and selectivity of membranes by increasing the CO2 solubility and providing a selective CO2 transport highway. For instance, the CO2 permeability of mixed gas (15% CO2/85% N-2, 50% CO2/50% CH4) permeation tests for 2.0 wt % PAN-NH2/PEO was increased from 340 Barrer (crosslinked PEO) to 1160 Barrer along with CO2/N-2 selectivity of 73.0 and CO2/CH4 selectivity of 19.7, surpassing the Upper bound (2019) and Upper bound (2008), respectively. The long-time stability of PAN-NH2/PEO MMMs is good, which endow them with great potential in practical CO2 capture. In addition, this work demonstrates the potential of functional ultramicroporous PMS in the preparation of high-performance MMMs for other gas separation processes

    <span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;color:black;mso-ansi-language:EN-GB;mso-fareast-language:EN-US; mso-bidi-language:HI" lang="EN-GB">Synthesis and characterization of functional superparamagnetic nanocomposites containing γ-Fe<sub>2</sub>O<sub>3</sub>, dexamethasone sodium phosphate and polyaniline</span>

    No full text
    207-213Superparamagnetic nanomaterials are showing great prospects in medical treatment with targeted medicine. A conceptually new method has been developed for the synthesis of a superparamagnetic nanocomposite, γ-Fe2O3/PANI-DSP (γ-Fe2O3/PANI doped with dexamethasone sodium phosphate). The properties of γ-Fe2O3/PANI-DSP are tested using FTIR, UV-vis, energy dispersive X-ray, vibrating sample magnetometer, transmission electron microscopy and cyclic voltammetry. The results show that the electric conductivity of γ-Fe2O3/PANI-DSP is as high as 0.11 S cm-1, while the saturated magnetizations of γ-Fe2O3/PANI-DSP (11.3 emu g-1) decreases in comparison with γ-Fe2O3/PANI (29.1 emu g-1). The morphology of γ-Fe2O3/PANI-DSP appears as spherical particles with a diameter of approximately 50 nm, which indicates that γ-Fe2O3/PANI-DSP would be highly favored in the chemotherapy of a variety of cancers
    corecore