165 research outputs found
The Role of CXCR3 in the Induction of Primary Biliary Cirrhosis
Objective. Investigate whether CXCR3 and its ligands were involved in the pathogenesis of primary biliary cirrhosis (PBC) in an autoimmune cholangitis animal model. Methods. Female C57BL/6 mice were injected with 5 mg/kg of poly I:C intraperitoneally twice a week for 24 weeks. PBC model was confirmed by liver function, serum autoantibodies and liver biopsy. Lymphocytes subsets in liver and spleen and CXCL10 serum level were tested by flow cytometry and ELISA. Liver specimens were collected to evaluate the differences in pathology between WT and CXCR3−/− mice. Results. Antimitochondrial antibody was detected in all PBC model. Numbers of infiltrates were detected in the portal areas 8 weeks after poly I:C injection, which progressed up to 24 weeks. Compared to control mice, CXCL10 serum level increased in PBC mice and the proportion of CXCR3+ cells increased in the intrahepatic infiltrates of PBC mice, chiefly on CD8+ cells, whereas the expression of CXCR3 on CD3+ and CD8+ splenocytes decreased in PBC model. Compared with WT mice, CXCR3−/− mice developed delayed and milder progression of cellular inflammation. Conculsions. CXCR3 might contribute to the development of PBC in murine model. Knockout of CXCR3 might delay and alleviate the PBC disease progression, but could not entirely block the disease development
Security and privacy in smart cities: challenges and opportunities
Smart cities are expected to improve the quality of daily life, promote sustainable development, and improve the functionality of urban systems. Now that many smart systems have been implemented, security and privacy issues have become a major challenge that requires effective countermeasures. However, traditional cybersecurity protection strategies cannot be applied directly to these intelligent applications because of the heterogeneity, scalability, and dynamic characteristics of smart cities. Furthermore, it is necessary to be aware of security and privacy threats when designing and implementing new mechanisms or systems. Motivated by these factors, we survey the current situations of smart cities with respect to security and privacy to provide an overview of both the academic and industrial fields and to pave the way for further exploration. Specifically, this survey begins with an overview of smart cities to provide an integrated context for readers. Then, we discuss the privacy and security issues in current smart applications along with the corresponding requirements for building a stable and secure smart city. In the next step, we summarize the existing protection technologies. Finally, we present open research challenges and identify some future research directions
Structural and Functional Alterations in Visual Pathway After Optic Neuritis in MOG Antibody Disease: A Comparative Study With AQP4 Seropositive NMOSD
Background: Optic neuritis (ON) is an important clinical manifestation of neuromyelitis optic spectrum disease (NMOSD). Myelin oligodendrocyte glycoprotein (MOG) antibody-related and aquaporin 4 (AQP4) antibody-related ON show different disease patterns. The aim of this study was to explore the differences in structure and function of the visual pathway in patients with ON associated with MOG and AQP4 antibodies.Methods: In this prospective study, we recruited 52 subjects at Beijing Tiantan Hospital, including 11 with MOG Ig+ ON (MOG-ON), 13 with AQP4 Ig+ ON (AQP4-ON), and 28 healthy controls (HCs). Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of optic radiation (OR), primary visual cortex volume (V1), brain volume, and visual acuity (VA) were compared among groups. A multiple linear regression was used to explore associations between VA and predicted factors. In addition, we used optical coherence tomography (OCT) to examine thickness of the peripapillary retinal nerve fiber layer (pRNFL) and retinal ganglion cell complex (GCC) in a separate cohort consisting of 15 patients with ON (8 MOG-ON and 7 AQP4-ON) and 28 HCs.Results: Diffusion tensor imaging showed that the FA of OR was lower than controls in patients with AQP4-ON (p = 0.001) but not those with MOG-ON (p = 0.329) and was significantly different between the latter two groups (p = 0.005), while V1 was similar in patients with MOG-ON and AQP4-ON (p = 0.122), but was lower than controls in AQP4-ON (p = 0.002) but not those with MOG-ON (p = 0.210). The VA outcomes were better in MOG-ON than AQP4-ON, and linear regression analysis revealed that VA in MOG-ON and AQP4-ON was both predicted by the FA of OR (standard β = −0.467 and −0.521, p = 0.036 and 0.034). Both patients of MOG-ON and AQP4-ON showed neuroaxonal damage in the form of pRNFL and GCC thinning but showed no statistically significant difference (p = 0.556, 0.817).Conclusion: The structural integrity of OR in patients with MOG-ON, which is different from the imaging manifestations of AQP4-ON, may be a reason for the better visual outcomes of patients with MOG-ON
Atmospheric deposition and river runoff stimulate the utilization of dissolved organic phosphorus in coastal seas
In coastal seas, the role of atmospheric deposition and river runoff in dissolved organic phosphorus (DOP) utilization is not well understood. Here, we address this knowledge gap by combining microcosm experiments with a global approach considering the relationship between the activity of alkaline phosphatases and changes in phytoplankton biomass in relation to the concentration of dissolved inorganic phosphorus (DIP). Our results suggest that the addition of aerosols and riverine water stimulate the biological utilization of DOP in coastal seas primarily by depleting DIP due to increasing nitrogen concentrations, which enhances phytoplankton growth. This “Anthropogenic Nitrogen Pump” was therefore identified to make DOP an important source of phosphorus for phytoplankton in coastal seas but only when the ratio of chlorophyll a to DIP [Log10 (Chl a / DIP)] is larger than 1.20. Our study therefore suggests that anthropogenic nitrogen input might contribute to the phosphorus cycle in coastal seas
Biomonitoring Study of Deoxynivalenol Exposure in Chinese Inhabitants
Objective: To investigate the levels of a deoxynivalenol (DON) biomarker in the urine of subjects living in two China provinces with different geographic locations and dietary patterns, and estimate their dietary DON exposures and health risks. Methods: First morning urine samples were collected on three consecutive days from 599 healthy subjects—301 from Henan province and 298 from Sichuan province—to analyze the total DON concentrations (tDON) after β-glucuronidase hydrolysis using a high-performance liquid chromatography tandem mass spectrometry-based method. The consumption of cereal foods in the previous 24 h before each urine collection was recorded using a duplicate diet method. DON exposure levels were estimated based on the urinary tDON concentrations. Results: Total DON were detected in 100% and 92% of the urine samples from Henan and Sichuan, respectively. Mean urinary tDON concentrations were 52.83 ng/mL in Henan subjects and 12.99 ng/mL in Sichuan subjects, respectively. The tDON levels were significantly higher in the urine of Henan subjects than that of the Sichuan subjects (p < 0.001). Urinary tDON levels were significantly different among age groups in both areas (Henan: p < 0.001; Sichuan: p = 0.026) and were highest in adolescents aged 13–17 years, followed by children aged 7–12 years. Based on the DON biomarker and exposure conversion reported by the European Food Safety Authority (EFSA), the mean estimated dietary intakes of DON were 1.82 μg/kg bw/day in Henan subjects and 0.45 μg/kg bw/day in Sichuan subjects. A total of 56% of Henan subjects and 12% of Sichuan subjects were estimated to exceed the PMTDI of 1 μg/kg bw/day. Consistent with urinary tDON levels, the highest estimated dietary DON intakes were also in children and adolescents aged 7–17 years. For all kinds of wheat-based foods except dumplings, the consumptions were significantly higher in Henan than those in Sichuan. The mean consumption of steamed buns was 8.4-fold higher in Henan (70.67 g/d) than that in Sichuan (8.45 g/d). The mean consumption of noodles in Henan (273.91 g/d) was 3.6-fold higher than that in Sichuan (75.87 g/d). Conclusions: The levels of urinary DON biomarker and the estimated dietary DON intakes in Henan province were high and concerning, especially for children and adolescents. The overall exposure level of Sichuan inhabitants was low
Phosphate glass fibers facilitate proliferation and osteogenesis through Runx2 transcription in murine osteoblastic cells
Cell-material interactions and compatibility are important aspects of bioactive materials for bone tissue engineering. Phosphate glass fiber (PGF) is an attractive inorganic filler with fibrous structure and tunable composition, which has been widely investigated as a bioactive filler for bone repair applications. However, the interaction of osteoblasts with PGFs has not been widely investigated to elucidate the osteogenic mechanism of PGFs. In this study, different concentrations of short PGFs with interlaced oriented topography were co-cultured with MC3T3-E1 cells for different periods, and the synergistic effects of fiber topography and ionic product of PGFs on osteoblast responses including cell adhesion, spreading, proliferation and osteogenic differentiation were investigated. It was found that osteoblasts were more prone to adhere on PGFs through vinculin protein, leading to enhanced cell proliferation with polygonal cell shape and spreading cellular actin filaments. In addition, osteoblasts incubated on PGF meshes showed enhanced alkaline phosphatase (ALP) activity, extracellular matrix mineralization, and increased expression of osteogenesis-related marker genes, which could be attributed to the Wnt/β-catenin/Runx2 signaling pathway. This study elucidated the possible mechanism of PGF on triggering specific osteoblast behavior, which would be highly beneficial for designing PGF-based bone graft substitutes with excellent osteogenic functions
Alterations in brain structure and function associated with pediatric growth hormone deficiency: A multi-modal magnetic resonance imaging study
IntroductionPediatric growth hormone deficiency (GHD) is a disease resulting from impaired growth hormone/insulin-like growth factor-1 (IGF-1) axis but the effects of GHD on children’s cognitive function, brain structure and brain function were not yet fully illustrated.MethodsFull Wechsler Intelligence Scales for Children, structural imaging, diffusion tensor imaging, and resting-state functional magnetic resonance imaging were assessed in 11 children with GHD and 10 matched healthy controls.Results(1) The GHD group showed moderate cognitive impairment, and a positive correlation existed between IGF-1 levels and cognitive indices. (2) Mean diffusivity was significantly increased in both corticospinal tracts in GHD group. (3) There were significant positive correlations between IGF-1 levels and volume metrics of left thalamus, left pallidum and right putamen but a negative correlation between IGF-1 levels and cortical thickness of the occipital lobe. And IGF-1 levels negatively correlated with fractional anisotropy in the superior longitudinal fasciculus and right corticospinal tract. (4) Regional homogeneity (ReHo) in the left hippocampus/parahippocampal gyrus was negatively correlated with IGF-1 levels; the amplitude of low-frequency fluctuation (ALFF) and ReHo in the paracentral lobe, postcentral gyrus and precentral gyrus were also negatively correlated with IGF-1 levels, in which region ALFF fully mediates the effect of IGF-1 on working memory index.ConclusionMultiple subcortical, cortical structures, and regional neural activities might be influenced by serum IGF-1 levels. Thereinto, ALFF in the paracentral lobe, postcentral gyrus and precentral gyrus fully mediates the effect of IGF-1 on the working memory index
Altered Brain Structure and Functional Connectivity of Primary Visual Cortex in Optic Neuritis
Previous studies have revealed brain adaptations to injury that occurs in optic neuritis (ON); however, the mechanisms underlying the functional connectivity (FC) and gray matter volume (GMV) changes in ON have not been clarified. Here, 51 single attack ON patients and 45 recurrent attacks ON patients were examined using structural MRI and resting-state functional MRI (RS-fMRI), and compared to 49 age- and gender-matched healthy controls (HC). FC analysis with a seed in primary visual cortex (V1 area) was used to assess the differences among three groups. Whole brain GMV was assessed using voxel-based morphometry (VBM). Correlation analyses were performed between FC results, structural MRI and clinical variables. We found positive correlations between the Paced Auditory Serial Addition Test (PASAT) score and FC in V1 area with bilateral middle frontal gyrus. Disease duration is significantly negatively related to FC in V1 area with the left inferior parietal lobule. Compared to the HC, single attack ON patients were found to have decreased FC values in the frontal, temporal lobes, right inferior occipital gyrus, right insula, right inferior parietal lobule, and significant increased FC values in the left thalamus. Recurrent attacks ON patients had the same pattern with single attack ON. No significant differences were found in brain GMV among three groups. This study provides the imaging evidence that impairment and compensation of V1 area connectivity coexist in ON patients, and provides important insights into the underlying neural mechanisms of ON
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