128 research outputs found

    A tunable plasmonic refractive index sensor with nanoring-strip graphene arrays

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    In this paper, a tunable plasmonic refractive index sensor with nanoring-strip graphene arrays is numerically investigated by the finite difference time domain (FDTD) method. The simulation results exhibit that by changing the sensing medium refractive index nmed of the structure, the sensing range of the system is large. By changing the doping level ng, we noticed that the transmission characteristics can be adjusted flexibly. The resonance wavelength remains entirely the same and the transmission dip enhancement over a big range of incidence angles [0,45] for both TM and TE polarizations, which indicates that the resonance of the graphene nanoring-strip arrays is insensitive to angle polarization. The above results are undoubtedly a new way to realize various tunable plasmon devices, and may have a great application prospect in biosensing, detection and imaging

    Association of CYP1B1 Polymorphisms with Breast Cancer: A Case-Control Study in the Han Population in Ningxia Hui Autonomous Region, P. R. China

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    Studies investigating possible associations between cytochrome P4501B1 (CYP1B1) polymorphisms and breast cancer risk have been inconsistent. We set out to ascertain whether there might be an association between polymorphisms in exon 2 (codon 119, G→T) and exon 3 (codon 432, G→C) of CYP1B1 and breast cancer in a Chinese Han population in the rural region of Ningxia. Using an allele-specific polymerase chain reaction method and direct DNA sequencing, the presence or absence of the two CYP1B1 polymorphisms was investigated. Genotype and allele frequencies were analyzed in breast cancer cases (n = 152) and healthy age-matched controls (n = 156). The odds ratio (OR) of 119G→T or 432G→C in breast cancer cases and controls was 3.3 (95% CI: 1.28 to 8.28) and 2.8 (95% CI: 1.04 to 7.51), respectively. In addition, the OR for people with both polymorphisms (119T and 432C) was 4.69 (95% CI: 1.97 to 11.19). Our results suggest that certain polymorphisms in the CYP1B1 gene might increase risk for breast cancer among Han Chinese, perhaps because they influence the efficiency of CYP1B1 bio-transformation of oestrogens or pro-carcinogens into DNA-reactive electrophiles that may act as cancer-initiating agents

    Moderate Exercise Enhances Endothelial Progenitor Cell Exosomes Release and Function

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    Purpose: Exercise has cardiovascular benefits which might be related to endothelial progenitor cells (EPC). Meanwhile, there is evidence suggesting that EPC-derived exosomes (EPC-EX) promote vascular repair and angiogenesis through their carried microRNA (miR)-126. In this study, we investigated whether exercise could increase the levels of circulating EPC-EX and their miR-126 cargo, and by which promote the protective function of EPC-EX on endothelial cells (EC). Methods: Plasma EPC-EX from sedentary, low, or moderate exercise mice, respectively, denoted as EPC-EXS, EPC-EXL, and EPC-EXM, were isolated using microbead-based sorting techniques and characterized by nanoparticle tracking analysis, Western blot, and quantitative real-time polymerase chain reaction assessments of biomarkers and miR-126. High glucose (25 mM) with hypoxia (1% O2) was used for inducing an EC injury model. The injured EC were treated by coculturing with vehicle, EPC-EXS, EPC-EXL, EPC-EXM, or EPC-EXM + anti–miR-126. After that, EC were used for flow cytometry analysis of apoptosis, assessments of tube formation and migration, and measurements of miR-126 level and its downstream sprouty-related protein-1 (SPRED1) and vascular endothelial growth factor (VEGF). Results: 1) Isolated EPC-EX positively expressed exosomal markers (CD63 and Tsg101) and EPC markers (CD34 and VEGFR2). 2) Exercise intensity dependently elevated plasma level of EPC, EPC-EX/EPC ratio, and miR-126 expression in EPC and EPC-EX. 3) Injured EC displayed apoptosis increment, angiogenic dysfunction and miR-126 reduction. 4) EPC-EXM had better effects than EPC-EXS and EPC-EXL on alleviating those changes of injured EC, accompanied with SPRED1 downregulation and VEGF upregulation. 5) The effects of EPC-EXM were abolished by miR-126 knockdown. Conclusions: Our data demonstrate that exercise can increase EPC-EX release and miR-126 level and enhance the effects of EPC-EX on protecting EC against injury through the SPRED1/VEGF pathway

    Efficacy of non-pharmacological interventions for sleep quality in Parkinson’s disease: a systematic review and network meta-analysis

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    BackgroundSleep disorders are one of the most common non-motor symptoms in PD. It can cause a notable decrease in quality of life and functioning in PD patients, as well as place a huge burden on both patients and caregivers. Currently, there are numerous non-pharmacological interventions available to improve sleep quality in PD, with disagreement as to which intervention is most effective. This network meta-analysis was performed to compare and rank non-pharmacological interventions to explore their efficacy in improving sleep quality in PD and to select the best interventions, with a view to providing references and bases for the development of clinical treatments and care programs.MethodsThe PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched from inception to December 6, 2023. Two authors independently screened all studies, extracted the data, and evaluated risk of bias of included studies. STATA software version 17.0 was used to conduct the network meta-analysis.ResultsOur network meta-analysis included 29 studies involving 1,477 participants and 16 non-pharmacological interventions. Although most nonpharmacological interventions showed non-significant effects, the surface under the cumulative ranking curve (SUCRA) values indicated that the best non-pharmacological intervention for sleep disorders was massage therapy (97.3%), followed by music therapy (94.2%), and Treadmill training (85.7%).ConclusionMassage therapy can be considered as an effective therapy for improving sleep quality in patients with PD. Due to limited quantity and quality of the included studies, more high quality studies are required to verify the conclusions of this network meta-analysis.Systematic review registrationidentifier CRD42023429339, PROSPERO (york.ac.uk)

    A tunable plasmonic refractive index sensor with nanoring-strip graphene arrays

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    In this paper, a tunable plasmonic refractive index sensor with nanoring-strip graphene arrays is numerically investigated by the finite difference time domain (FDTD) method. The simulation results exhibit that by changing the sensing medium refractive index nmed of the structure, the sensing range of the system is large. By changing the doping level ng, we noticed that the transmission characteristics can be adjusted flexibly. The resonance wavelength remains entirely the same and the transmission dip enhancement over a big range of incidence angles [0,45] for both TM and TE polarizations, which indicates that the resonance of the graphene nanoring-strip arrays is insensitive to angle polarization. The above results are undoubtedly a new way to realize various tunable plasmon devices, and may have a great application prospect in biosensing, detection and imaging

    Aberrant structural and functional alterations in postpartum depression: a combined voxel-based morphometry and resting-state functional connectivity study

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    ObjectivesPostpartum depression (PPD) is a severe postpartum psychiatric disorder with unclear pathogenesis. Previous neuroimaging studies have reported structural or functional alterations in areas associated with emotion regulation, cognitive disorder, and parenting behaviors of PPD. The primary goal of this investigation was to explore the presence of brain structural alterations and relevant functional changes in PPD patients.MethodsA total of 28 patients and 30 matched healthy postnatal women (HPW) underwent both three-dimensional T1-weighted magnetic resonance imaging (MRI) and resting-state functional MRI. Structural analysis was performed by voxel-based morphometry (VBM), followed by resting-state functional analysis using a seed-based whole-brain functional connectivity (FC) approach with abnormal gray matter volume (GMV) regions as seed.ResultsCompared with HPW, the PPD patients showed increased GMV in the left dorsolateral prefrontal cortex (DLPFC.L), the right precentral gyrus (PrCG.R), and the orbitofrontal cortex (OFC). In the PPD group, the DLPFC.L showed increased FC with the right anterior cingulate and paracingulate gyri (ACG.R) and the right middle frontal gyrus (MFG.R); the FC between the PrCG.R and the right median cingulate and paracingulate gyri (DCG.R) exhibited enhanced; the OFC showed increased FC with MFG.R and the left inferior occipital gyrus (IOG.L). In PPD, GMV of DLPFC.L was positively correlated with EDPS scores (r = 0.409 p = 0.031), and FC of PrCG.R-DCG.R was positively correlated with EDPS scores (r = 0.483 p = 0.020).ConclusionStructural and functional damage of the DLPFC.L and OFC is associated with cognitive disorders and parenting behaviors in PPD, while structural abnormalities of the DLPFC.L and PrCG.R are involved in impaired executive function. The increased GMV of DLPFC.L may be a unique structural pathological mechanism of PPD related to the inability of PPD patients to withstand long-term parenting stress. These findings have important implications for understanding neural mechanisms in PPD

    Cerebellum and hippocampus abnormalities in patients with insomnia comorbid depression: a study on cerebral blood perfusion and functional connectivity

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    Chronic insomnia disorder and major depressive disorder are highly-occurred mental diseases with extensive social harm. The comorbidity of these two diseases is commonly seen in clinical practice, but the mechanism remains unclear. To observe the characteristics of cerebral blood perfusion and functional connectivity in patients, so as to explore the potential pathogenesis and biological imaging markers, thereby improving the understanding of their comorbidity mechanism. 44 patients with chronic insomnia disorder comorbid major depressive disorder and 43 healthy controls were recruited in this study. The severity of insomnia and depression were assessed by questionnaire. The cerebral blood perfusion and functional connectivity values of participants were obtained to, analyze their correlation with questionnaire scores. The cerebral blood flow in cerebellum, vermis, right hippocampus, left parahippocampal gyrus of patients were reduced, which was negatively related to the severity of insomnia or depression. The connectivities of left cerebellum-right putamen and right hippocampus-left inferior frontal gyrus were increased, showing positive correlations with the severity of insomnia and depression. Decreased connectivities of left cerebellum-left fusiform gyrus, left cerebellum-left occipital lobe, right hippocampus-right paracentral lobule, right hippocampus-right precentral gyrus were partially associated with insomnia or depression. The connectivity of right hippocampus-left inferior frontal gyrus may mediate between insomnia and depression. Insomnia and depression can cause changes in cerebral blood flow and brain function. Changes in the cerebellar and hippocampal regions are the result of insomnia and depression. They reflect abnormalities in sleep and emotion regulation. That may be involved in the pathogenesis of comorbidity

    Initial Soil Organic Matter Content Influences the Storage and Turnover of Litter, Root and Soil Carbon in Grasslands

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    Grassland degradation is a worldwide problem that often leads to substantial loss of soil organic matter (SOM). To estimate the potential for carbon (C) accumulation in degraded grassland soils, we first need to understand how SOM content influences the transformation of plant C and its stabilization within the soil matrix. We conducted a greenhouse experiment using C3 soils with six levels of SOM content; we planted the C4 grass Cleistogenes squarrosa or added its litter to the soils to investigate how SOM content regulates the storage of new soil C derived from litter and roots, the decomposition of extant soil C, and the formation of soil aggregates. We found that with the increase in SOM content, microbial biomass carbon (MBC) and the mineralization of litter C increased. Both the litter addition and planted treatments increased the amount of new C inputs to soil. However, the mineralization of extant soil C was significantly accelerated by the presence of living roots but was not affected by litter addition. Accordingly, the soil C content was significantly higher in the litter addition treatments but was not affected by the planted treatments by the end of the experiment. The soil macroaggregate fraction increased with SOM content and was positively related to MBC. Our experiment suggests that as SOM content increases, plant growth and soil microbial activity increase, which allows microbes to process more plant-derived C and promote new soil C formation. Although long-term field experiments are needed to test the robustness of our findings, our greenhouse experiment suggests that the interactions between SOM content and plant C inputs should be considered when evaluating soil C turnover in degraded grasslands
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