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1.
Artigo em Inglês | MEDLINE | ID: mdl-32409998

RESUMO

PURPOSE: The exact significance of type 2 endoleaks (T2ELs) and the indication and efficacy of treatment are widely debated. We report our experience with managing T2ELs in a tertiary Asian centre. MATERIALS AND METHODS: This was a retrospective study of patients who underwent endovascular abdominal aortic aneurysm repair (EVAR) between February 2006 and December 2016. Patients with T2ELs were identified, and their data were analysed. RESULTS: A total of 156 patients underwent EVAR, of which 67 (42.9%) developed T2ELs. Seven were lost to follow-up. The remaining 60 patients had a mean follow-up period of 50.3 ± 33.9 months-34 (56.7%) experienced T2ELs early and the rest (43.3%) had late T2ELs. Forty-one patients had isolated T2EL, whilst 19 had concomitant T1EL and/or T3EL. Spontaneous resolution occurred in 25 patients (41.7%). All T2ELs with stable sac size were on continued surveillance. Amongst those with persistent T2ELs associated with sac growth (n = 17), 14 underwent intervention, of which 7 (50%) received > 1 embolisation procedure. A total of 16 transarterial embolisation and 8 translumbar embolisation procedures were performed. Technical success rate was 75%. In the intervention group, 5 (35.7%) had complete and sustained resolution, 7 had persistent/recurrent T2ELs but stable sac size, and 2 had progressive sac expansion. Overall mortality due to sac rupture occurred in 2 patients with concomitant T2EL and T1EL/T3EL. CONCLUSION: T2ELs are common, albeit mostly benign if occurring in isolation and not in association with sac growth. Achieving complete T2EL resolution with embolisation is difficult even with reinterventions. LEVEL OF EVIDENCE: Level 2B, retrospective study.

2.
Neuroscience ; 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32417340

RESUMO

White matter lesions are common when global cerebral ischemia (GCI) occurs in the elderly, and cause damage to neurological and psychological functions. Remyelination often fails because of the limited recruitment of oligodendrocyte progenitor cells (OPCs) to the demyelinated site or the inefficient differentiation of OPCs to mature oligodendrocytes (OLs). The activation of microglia, the most important immune cells in the central nervous system, and subsequent inflammation have been implicated in myelination repair disorder. Little is known about the role of the Fractalkine/CX3CR1 signaling pathway, the key regulator of microglia activation, on myelin in microglia. In this study, a GCI animal model was generated through bilateral common carotid artery occlusion to induce ischemic inflammation and white matter damage; then, we downregulated CX3CR1 by intracerebroventricular administration of neutralizing antibody anti-FKR. Downregulation of CX3CR1 significantly reversed the depression-like behavior and cognitive impairment in GCI mice. Activation of microglia was inhibited, and the peripheral inflammatory responses were also ameliorated as revealed by decreased serum levels of IL-1ß, IL-6 and TNF-α. CX3CR1 block substantially reversed demyelination in striatum, cortex and hippocampus and promoted differentiation and maturation of OPCs into mature OLs in the hippocampus. No effect was found on myelin in the corpus callosum. Besides, hippocampal neurons were protected by anti-FKR treatment after GCI. Collectively, our data demonstrated that downregulating of the Fractalkine/CX3CR1 signaling pathway had an anti-depressant and cognition-improvement effect by inhibiting microglia activation, promoting OPCs maturation and remyelination.

3.
Pestic Biochem Physiol ; 164: 173-182, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32284124

RESUMO

Athetis lepigone (Alep) is a polyphagous pest native to Europe and Asia that has experienced major outbreaks in the summer maize area of China since 2011 and has shown evidence of resistance to some insecticides. Insect olfaction is crucial for recognition of sex pheromones, host plant volatiles and even insecticides, in which two general-odorant binding proteins (GOBPs) play important roles. To elucidate the functions of GOBPs in A. lepigone, we first expressed the two AlepGOBP proteins in the E. coli expression system. Then, the results of fluorescence competitive binding assays demonstrated that the high binding affinity of AlepGOBP2 with sex pheromones [(Z)-7-dodecenyl acetate (Z7-12:Ac), Ki = 0.65 µM; (Z)-9-tetradecenyl acetate (Z9-14:Ac), Ki = 0.83 µM], two maize plant volatiles [Ocimene, Ki = 9.63 µM; (E)-ß-Farnesene, Ki = 4.76 µM] and two insecticides (Chlorpyrifos Ki =5.61 µM; Phoxim, Ki = 4.38 µM). However, AlepGOBP1 could only bind Ocimene (Ki = 13.0 µM) and two insecticides (Chlorpyrifos Ki =4.46 µM; Phoxim, Ki = 3.27 µM). These results clearly suggest that AlepGOBP1 and AlepGOBP2 differentiate among odorants and other ligands. The molecular docking results further revealed different key residues involved in the ligand binding of AlepGOBPs. In summary, this study provides a foundation for exploring the olfactory mechanism of A. lepigone and identified two potential target genes for the development of highly effective insecticides in the future.


Assuntos
Inseticidas , Mariposas , Atrativos Sexuais , Animais , China , Escherichia coli , Proteínas de Insetos , Simulação de Acoplamento Molecular , Odorantes , Feromônios
4.
Structure ; 28(5): 540-547.e3, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142641

RESUMO

Francisella tularensis is the causative agent for the potentially fatal disease tularemia. The lipoprotein Flpp3 has been identified as a virulence determinant of tularemia with no sequence homology outside the Francisella genus. We report a room temperature structure of Flpp3 determined by serial femtosecond crystallography that exists in a significantly different conformation than previously described by the NMR-determined structure. Furthermore, we investigated the conformational space and energy barriers between these two structures by molecular dynamics umbrella sampling and identified three low-energy intermediate states, transitions between which readily occur at room temperature. We have also begun to investigate organic compounds in silico that may act as inhibitors to Flpp3. This work paves the road to developing targeted therapeutics against tularemia and aides in our understanding of the disease mechanisms of tularemia.

5.
Sci Total Environ ; 719: 137124, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32120092

RESUMO

Constructed wetland is an efficient and convenient wastewater treatment technology that has been widely used in China and elsewhere. However, seasonal frozen soil is easily formed in the cold regions of northern China. The local wetlands are in the frozen soil layer, causing the pollutants from wastewater not to be removed well. Therefore, a new constructed wetland structure that uses shallow geothermal energy to keep the wetland not frozen in the winter is proposed in this paper. The results of the experiment show that the average removal rates of total nitrogen, ammonium ion, and total phosphorus in the multistage constructed wetland system are 54.8%, 44.5%, and 77.7%, respectively. This performance is substantially better than that of conventional wetlands in winter. The proposed wetland structure can be applied to conventional wetlands and avoid the conventional wetlands being idle during cold seasons, which is conducive to the popularization of constructed wetlands (CWs) in cold regions.

6.
Curr Neurovasc Res ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32056526

RESUMO

OBJECTIVE: The effects of mesenchymal stem cell (MSC)-derived exosomes on brain microvascular endothelial cells under oxygen-glucose deprivation (OGD), which mimics cells in deep hypothermic circulatory arrest (DHCA) in vitro, are yet to be studied. METHODS: MSCs were co-cultured with primary rat brain endothelial cells, which were then exposed to OGD. Cell viability, apoptosis, the inflammatory factors (IL-1ß, IL-6, and TNF-α), and the activation of inflammation-associated TLR4-mediated pyroptosis and the NF-κB signaling pathway were determined. Furthermore, exosomes derived from MSCs were isolated and incubated with endothelial cells to investigate whether the effect of MSCs is associated with MSC-derived exosomes. Apoptosis, cell viability, and the inflammatory response were also analyzed in OGD-induced endothelial cells incubated with MSC-derived exosomes. RESULTS: OGD treatment promoted endothelial cell apoptosis, induced the release of inflammatory factors IL-1ß, IL-6, and TNF-α, and inhibited cell viability. Western blot analysis showed that OGD treatment induced TLR4, and NF-κB p65 subunit phosphorylation and caspase-1 upregulation, while co-culture with MSCs could reduce the effect of OGD treatment on endothelial cells. As expected, the effect of MSC-derived exosomes on OGD-treated endothelial cells was similar to that of MSCs. MSC-derived exosomes alleviated the OGD-induced decrease in the viability of endothelial cells, and increased levels of apoptosis, inflammatory factors, and the activation of inflammatory and inflammatory focal pathways. CONCLUSION: Both MSCs and MSC-derived exosomes attenuated OGD-induced rat primary brain endothelial cell injury. These findings suggest that at least some of the protective effects of MSCs on endothelial cells are mediated by MSC-derived exosomes.

7.
World Neurosurg ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32081829

RESUMO

BACKGROUND: Spinal dural arteriovenous fistula (SDAVF) is a rare spinal vascular malformation which can cause permanent neurologic dysfunction. The purpose of this study was to investigate the relationship between the clinical and imaging characteristics of SDAF and its prognosis. METHODS: All patients diagnosed with SDAVF and hospitalized in our hospital from February 2004 to September 2018 were retrospectively recruited. The clinical and imaging data of these patients were collected, and then a subgroup analysis was performed to find the association between clinical and imaging characteristics of SDAF and its prognosis. RESULTS: A total of 79 patients were included in the analysis. The median age of the patients was 59 years, with men having a predominant morbidity (84.4%). The mean duration of symptoms was 7 months, and most patients had more than 2 symptoms before hospitalization (n = 43, 44.4%). The fistula mainly occurred in the lower thoracic spine (n = 40, 50.6%), followed by the lumbar spine (n = 18, 22.8%) and upper thoracic spine (n = 16, 20.3%). Of 58 patients with magnetic resonance images available, 45 (77.6%) were identified with high T2-weighted image (T2WI) signal in the spinal cord, and 51 (87.9%) with T2WI flow voids on the spinal surface. Multivariate logistic regression analysis found that preoperative Aminoff-Logue Scale (ALS) scores were associated with postoperative function improvement after adjustment for sex, age, and duration of symptoms (P = 0.013; odds ratio, 1.375; 95% confidence interval, 1.07-1.77). CONCLUSIONS: Preoperative ALS scores are associated with improved prognosis in patients with SDAVF. Both surgical ligation and endovascular embolization can improve functional outcomes and delay disease progression.

8.
Sci Rep ; 10(1): 2135, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034218

RESUMO

Male germ cells are sensitive to heat stress and testes must be maintained outside the body for optimal fertility. However, no germ cell intrinsic mechanism that protects from heat has been reported. Here, we identify the germ cell specific Golgi glycoprotein MGAT4D as a protector of male germ cells from heat stress. Mgat4d is highly expressed in spermatocytes and spermatids. Unexpectedly, when the Mgat4d gene was inactivated globally or conditionally in spermatogonia, or mis-expressed in spermatogonia, spermatocytes or spermatids, neither spermatogenesis nor fertility were affected. On the other hand, when males were subjected to mild heat stress of the testis (43 °C for 25 min), germ cells with inactivated Mgat4d were markedly more sensitive to the effects of heat stress, and transgenic mice expressing Mgat4d were partially protected from heat stress. Germ cells lacking Mgat4d generally mounted a similar heat shock response to control germ cells, but could not maintain that response. Several pathways activated by heat stress in wild type were induced to a lesser extent in Mgat4d[-/-] heat-stressed germ cells (NFκB response, TNF and TGFß signaling, Hif1α and Myc genes). Thus, the Golgi glycoprotein MGAT4D is a novel, intrinsic protector of male germ cells from heat stress.

9.
Chem Commun (Camb) ; 56(14): 2123-2126, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-31970368

RESUMO

Here, we develop an optical tweezers-based single-molecule manipulation assay to detect the formation of an R-loop complex in the Cas12a system and characterize its thermodynamic stability. We found that the formation of the R-loop complex induces a two-step unfolding of a DNA hairpin containing the target sequence, the non-target sequence binds loosely to Cas12a and can be easily released from the complex, and the Nuc domain of Cas12a plays key roles in target binding and R-loop formation.


Assuntos
DNA/síntese química , Sistemas CRISPR-Cas/genética , DNA/química , DNA/genética , Pinças Ópticas , Termodinâmica
10.
J Proteomics ; 213: 103601, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31809900

RESUMO

Protein methylation has been proposed as an important post-translational modification, which occurs predominantly on lysine and arginine residues. Recent discoveries have revealed that protein methylation is also present on non-histones besides histones, and plays critical roles in regulating protein stability and function. However, proteome-wide identification of methylated proteins in plants remains unexplored. Here, we present the first global survey of monomethyl arginine, symmetric and asymmetric dimethyl arginine, and monomethyl, dimethyl, trimethyl lysine modifications in the proteomes of 10-day-old Arabidopsis seedlings through a combination of immunoaffinity purification and mass spectrometry analysis. In total, we identified 617 methylation sites which mapped to 412 proteins, with 263 proteins harboring 381 lysine methylation sites and 149 proteins harboring 236 arginine methylation sites. Among them, 607 methylation sites on 408 proteins were novel findings. Motif analysis revealed that glycine preferentially flanked methylated arginine residues, whereas aspartate and glutamate enriched around mono- and dimethylated lysine sites. Methylated proteins were involved in a variety of metabolic processes, showing significant enrichment in RNA-related metabolic pathways including spliceosome, RNA transport, and ribosome. Our data provide a global view of methylated non-histone proteins in Arabidopsis, laying foundations for elucidating the biological function of protein methylation in plants. SIGNIFICANCE: Protein methylation has emerged as a common and important modification both in eukaryotes and prokaryotes. The identification of methylated sites/peptides is fundamental for further functional analysis of protein methylation. This study was the first proteome-scale identification of lysine and arginine methylation in plants. We found that methylation occurred widely on non-histone proteins in Arabidopsis and was involved in diverse biological functions. The results provide foundations for the investigation of the protein methylome in Arabidopsis and provide powerful resources for the functional analysis of protein methylation in plants.

11.
Fish Shellfish Immunol ; 96: 177-189, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31811887

RESUMO

Suppressors of cytokine signaling (SOCS) family members have negative effects on cytokine signaling pathways involved in immunity, growth and development. Owing to their typical feature, they have been extensively studied in mammalians, but they have not offered systematic studies among teleosts. In the present study, nine SOCS family genes were identified in the swamp eel genome and analyzed regulation mechanisms of SOCS family members in swamp eels. The open reading frames of MaSOCS1a, MaSOCS1b, MaSOCS2, MaSOCS3a, MaSOCS3b, MaSOCS4, MaSOCS5, MaSOCS6 and MaSOCS7 were 663 bp, 603 bp, 717 bp, 618 bp, 645 bp, 1188 bp, 1488 bp, 1611 bp and 1998 bp and encoded 220, 238, 200, 205, 214, 395, 496, 536 and 655 amino acids, respectively. All SOCS proteins have no signal peptides. Multiple alignment revealed that MaSOCS family members possessed a typical conserved SOCS box and SH2 region. Phylogenetic analyses showed that all SOCS proteins were divided into two main clusters. Taken together with the similarity and identity of SOCS protein amino acids, these results indicated that MaSOCS family members shared conserved with other homologous genes, in which MaSOCS7 was more conserved. Further syntenic analysis confirmed the phylogenetic analysis results and annotation of SOCS protein, suggesting that MaSOCS5 shared a common ancestor gene with that of fish and humans. MaSOCS family members were constitutively expressed in a wide range of tissues with different levels. In particular, spleen and head kidneys play an important role in immune-related pathways. After Aeromonas veronii and polyinosinic-polycytidylic acid (poly I:C) challenge in the spleen and head kidney, MaSOCS family members exhibit different expression profiles. These expression patterns indicated that MaSOCS family members could make acute responses after pathogen invasion. Taken together, these results indicate that MaSOCS family members participate in the immune response against pathogens and offer a solid foundation for future studies of SOCS function.

12.
Neurol Sci ; 41(2): 271-280, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31758346

RESUMO

BACKGROUND AND OBJECTIVES: Parkinson's disease (PD) is one of the most common forms of neurodegenerative disorders, and its etiology remains unclear. Single nucleotide polymorphisms (SNPs) of alpha-synuclein (SNCA) have been found to be significantly associated with PD risk. In particular, the variant rs11931074 was found in one meta-analysis to appear to play a role in the occurrence of PD. This finding has been questioned in subsequent studies, however. The aim of this study was to determine the relationship between PD risk and rs11931074 polymorphism. METHODS: We performed a systematic online search, including PubMed, Web of Science, EMBASE, Cochrane Library, and CNKI (China National Knowledge Infrastructure), aiming to identify case-control studies looking at the role of rs11931074 in PD. We performed calculations of pooled odds ratio (OR) and 95% confidence interval (95% CI) to assess the associations, and subgroup meta-analyses to verify differences between various ethnicities of different study populations. RESULTS: A total of 13 studies involving 13,403 cases and 28,408 controls met the inclusion criteria after assessment by two reviewers. Overall, there exists significant associations between SNCA rs11931074 polymorphism and the risk of PD under five genetic models (allele contrast model: T vs. G, OR = 1.28, 95% CI = 1.12-1.45, P = 0.0001; homozygote model: TG vs. GG, OR = 1.55, 95% CI = 1.17-2.05, P = 0.002; heterozygote model (TT vs. GG, OR = 1.23, 95% CI = 1.05-1.42, P = 0.009; dominant model: TG+TT vs. GG: OR = 1.25, 95% CI = 1.05-1.50, P = 0.01 and recessive model: TT vs. TG+GG: OR = 1.40, 95% CI = 1.18-1.68, P = 0.0002). When ethnicities were stratified, significant associations were found in the allelic, homozygote, and recessive models for Asians, and in the allelic model for Caucasians. CONCLUSION: SNCA rs11931074 polymorphism is found to be associated with PD risk and this risk appears to be influenced by genetic status and ethnicity.

13.
Spine (Phila Pa 1976) ; 45(5): E272-E279, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513096

RESUMO

STUDY DESIGN: Cross-sectional study. OBJECTIVE: To analyze altered functional connectivity (FC) in the visual cortex of cervical spondylotic myelopathy (CSM) patients using resting-state functional magnetic resonance imaging (fMRI). SUMMARY OF BACKGROUND DATA: We previously showed changes in visual cortex neural activity in CSM patients. METHODS: Thirty CSM patients and 20 healthy controls were recruited. MR data were collected using a 3.0 T MR. FC of the regions of interest (ROI) (Brodmann areas [BA] 17/18/19/7) were calculated in a voxel-wise manner and compared between groups. Correlation analyses were performed between preoperative Japanese Orthopaedic Association (JOA) scores and altered FC, as well as between preoperative best corrected visual acuity (BCVA) and altered FC. Furthermore, the FC where was compared between the preoperative and the postoperative CSM patients in an ROI-wise manner. RESULTS: Increased FC was found between BA19 and the cerebellum inferior lobe; between the left BA7 and bilateral calcarine, right lingual, right fusiform gyrus, and left precuneus (BA17); between the left BA7 and right fusiform gyrus and right inferior occipital gyrus (right BA19); and between the right BA7 and right superior lobe of cerebellum (right BA19) in CSM patients (P < 0.05). A negative correlation was found between JOA score and FC of the left and right BA19, and a positive correlation was found between the BCVA and FC of the left and right BA7 (P < 0.05). ROI analysis demonstrated statistically significant FC differences in between the preoperative and the postoperative CSM patients (P < 0.05). CONCLUSION: FC changes were present in the visual cortex of CSM patients, which negatively correlated with preoperative JOA scores and positively correlated with preoperative BCVA. Significant recovery of FC in the visual cortex was detected in CSM patients postoperatively. LEVEL OF EVIDENCE: 4.

14.
Mol Psychiatry ; 25(3): 517-529, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31827248

RESUMO

The Chinese Imaging Genetics (CHIMGEN) study establishes the largest Chinese neuroimaging genetics cohort and aims to identify genetic and environmental factors and their interactions that are associated with neuroimaging and behavioral phenotypes. This study prospectively collected genomic, neuroimaging, environmental, and behavioral data from more than 7000 healthy Chinese Han participants aged 18-30 years. As a pioneer of large-sample neuroimaging genetics cohorts of non-Caucasian populations, this cohort can provide new insights into ethnic differences in genetic-neuroimaging associations by being compared with Caucasian cohorts. In addition to micro-environmental measurements, this study also collects hundreds of quantitative macro-environmental measurements from remote sensing and national survey databases based on the locations of each participant from birth to present, which will facilitate discoveries of new environmental factors associated with neuroimaging phenotypes. With lifespan environmental measurements, this study can also provide insights on the macro-environmental exposures that affect the human brain as well as their timing and mechanisms of action.

15.
Hum Brain Mapp ; 41(7): 1738-1753, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31868305

RESUMO

Clinical observations showed that schizophrenia (SCZ) patients reported little or no pain under various conditions that are commonly associated with intense painful sensations, leading to a higher risk of morbidity and mortality. However, this phenomenon has received little attention and its underlying neural mechanisms remain unclear. Here, we conducted two experiments combining psychophysics, electroencephalography (EEG), and functional magnetic resonance imaging (fMRI) techniques to investigate neural mechanisms of pain insensitivity in SCZ patients. Specifically, we adopted a stimulus-response paradigm with brief stimuli of different sensory modalities (i.e., nociceptive, non-nociceptive somatosensory, and auditory) to test whether pain insensitivity in SCZ patients is supra-modal or modality-specific, and used EEG and fMRI techniques to clarify its neural mechanisms. We observed that perceived intensities to nociceptive stimuli were significantly smaller in SCZ patients than healthy controls, whereas perceived intensities to non-nociceptive somatosensory and auditory stimuli were not significantly different. The behavioral results were confirmed by stimulus-evoked brain responses sampled by EEG and fMRI techniques, thus verifying the modality-specific nature of the modulation of nociceptive information processing in SCZ patients. Additionally, significant group differences were observed in the spectral power of alpha oscillations in prestimulus EEG and the seed-based functional connectivity in resting-state fMRI (seeds: the thalamus and periaqueductal gray that are key nodes in ascending and descending pain pathways respectively), suggesting a possible contribution of cortical-subcortical dysfunction to the phenomenon. Overall, our study provides insight into the neural mechanisms of pain insensitivity in SCZ and highlights a need for systematic assessments of their pain-related diseases.

16.
Int J Mol Sci ; 20(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795343

RESUMO

Cavity analysis in molecular dynamics is important for understanding molecular function. However, analyzing the dynamic pattern of molecular cavities remains a difficult task. In this paper, we propose a novel method to topologically represent molecular cavities by vectorization. First, a characterization of cavities is established through Word2Vec model, based on an analogy between the cavities and natural language processing (NLP) terms. Then, we use some techniques such as dimension reduction and clustering to conduct an exploratory analysis of the vectorized molecular cavity. On a real data set, we demonstrate that our approach is applicable to maintain the topological characteristics of the cavity and can find the change patterns from a large number of cavities.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31830509

RESUMO

BACKGROUND: Numerous neuroimaging studies have revealed that schizophrenia was characterized by wide-spread dysconnection among brain regions during rest measured by functional connectivity (FC). In contrast with FC, effective connectivity (EC) provides information about directionality of brain connections and is thus valuable in mechanistic investigation of schizophrenic brain. However, a systematic characterization of whole-brain resting-state EC (rsEC) and how it captures different information compared with resting-state FC (rsFC) in schizophrenia are still lacking. AIMS: To systematically characterize the abnormalities of rsEC, compared with rsFC, in schizophrenia, and to test its discriminative power as a neuroimaging marker for schizophrenia diagnosis. METHOD: Whole-brain rsEC and rsFC networks were constructed using resting-state fMRI data and compared between 103 patients with schizophrenia and 110 healthy participants. Pattern classifications between patients and controls based on whole-brain rsEC and rsFC were further performed using multivariate pattern analysis. RESULTS: We identified 17 rsEC significantly disrupted (mostly decreased) in patients, among which all were associated with the thalamus and 15 were from limbic areas (including hippocampus, parahippocampus and cingulate cortex) to the thalamus. In contrast, abnormal rsFC were widely distributed in the whole brain. The classification accuracies for distinguishing patients and controls using whole-brain rsEC and rsFC patterns were 78.6% and 82.7%, respectively, and was further improved to 84.5% when combining rsEC and rsFC. CONCLUSIONS: Schizophrenia is featured by disrupted 'limbic areas-to-thalamus' rsEC, in contrast with diffusively altered rsFC. Moreover, both rsEC and rsFC contain valuable and complementary information which may be used as diagnostic markers for schizophrenia.

18.
Huan Jing Ke Xue ; 40(6): 2624-2630, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854653

RESUMO

Atmospheric trace metal pollution is a striking environmental problem globally. Because of the limitations in monitoring data, our knowledge of the historical processes and sources of atmospheric trace metal pollution in China and its influence on remote terrestrial environmental quality is limited. The historical variations in atmospheric trace metal (Cd, Cr, Cu, Hg, Ni, Pb, and Zn) pollution during the past 400 years in the Fanjing Mountain area, northern Guizhou Province were studied by analyzing the metal concentrations and Pb isotopes in lake sediments. The results showed that concentrations of all metals in the sediments were relatively constant before 1800(A.D.). After 1800, concentrations of Cr, Cu, Ni, and Zn increased at first and then decreased, while concentrations of Hg, Cd, and Pb generally increased gradually over the most recent century and subsequent decades. The enrichment factor and 207Pb/206Pb analysis results indicated that Cd, Pb, and Hg were typical pollutants. Pollution of Hg began at around 1880(A.D.), and pollution of Cd and Pb has occurred since the 1950s; all pollutants exhibited aggravated trends in recent times. Pollution levels of Hg in recent years in the Fanjing Mountain area were comparable to those in other remote areas of East China, but levels were lower than those in Europe, America, and the Tibetan Plateau. In contrast, pollution levels of Cd and Pb in these areas showed large variability. By comparing the historical processes of trace metal pollution in different regions and exploring the potential pollution sources of metals in the study region, it can be deduced that atmospheric Hg pollution in the Fanjing Mountain area was the result of both global and regional emissions, while Cd and Pb pollution largely came from regional sources such as non-ferrous metals smelting and coal combustion emissions.

19.
Micromachines (Basel) ; 10(12)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766713

RESUMO

We report on a transient response model of thin cylindrical piezoelectric transducers used in the petroleum logging tools, parallel to a recently established transient response model of thin spherical-shell transducers. Established on a series of parallel-connected equivalent-circuits, this model provides insightful information on the physical characteristics of the thin cylindrical piezoelectric transducers, i.e., the transient response, center-frequency, and directivity of the transducer. We have developed a measurement system corresponding to the new model to provide a state-of-the-art comparison between theory and experiment. We found that the measured results were in good agreement with those of theoretical calculations.

20.
Front Pharmacol ; 10: 1247, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695615

RESUMO

Global cerebral ischemia (GCI) commonly occurs in the elderly. Subcortical white matter lesions and oligodendrocyte (OLG) loss caused by cerebral ischemia have been implicated in the development of post-ischemic depression and cognitive impairment. OLGs are necessary for axonal myelination; the disrupted differentiation of OLG progenitor cells (OPCs) is associated with impaired remyelination. Evidence has indicated that increased levels of inflammatory cytokines released from activated microglia induce depression-like behaviors by affecting neurotransmitter pathways, but the mechanisms remain elusive. We explored the potential mechanisms that link microglia activation with GCI-induced depression and cognitive dysfunction by studying effects of minocycline on white matter damage, cytokine levels, and the monoaminergic neurotransmitters. An acute GCI animal model was generated through bilateral common carotid artery occlusion to induce ischemic inflammation and subcortical white matter damage. Minocycline, an inhibitor of microglia activation, was intraperitoneally administrated immediately after surgery and continued daily for additional six days. Minocycline shortened the immobile duration in tail suspension test and forced swimming test, while no improvement was found in Morris water maze test. The plasma levels of IL-1ß, IL-6, TNF-α, HMGB1, and netrin-1 were significantly reduced with the treatment of minocycline. Minocycline treatment substantially reversed demyelination in corpus callosum and hippocampus, alleviated hippocampal microglia activation, and promoted OPCs maturation, while no effect was found on hippocampal neurodegeneration. Besides, the content of dopamine (DA) in the hippocampus was upregulated by minocycline treatment after GCI. Collectively, our data demonstrated that minocycline exerts an anti-depressant effect by inhibiting microglia activation, promoting OPCs maturation and remyelination. Increased DA in hippocampus may also play a role in ameliorating depressive behavior with minocycline treatment.

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