Publications by authors named "Jikai Wang"

10 Publications

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MFGE8 mitigates brain injury in a rat model of SAH by maintaining vascular endothelial integrity via TIGβ5/PI3K/CXCL12 signaling.

Exp Brain Res 2021 May 15. Epub 2021 May 15.

Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, No. 52 Meihuadong Road, Zhuhai, 519000, Guangdong, China.

Leaked blood components, injured endothelial cells, local inflammatory response and vasospasm may converge to promote microthrombosis following subarachnoid hemorrhage (SAH). Previously, we showed that the milk fat globule-epidermal growth factor 8 (MFGE8) can mitigate SAH-induced microthrombosis. This present study was aimed to explore the molecular pathway participated in MFGE8-dependent protection on vascular endothelium. Immunofluorescence, immunoblot and behavioral tests were used to determine the molecular partner and signaling pathway mediating the effect of MFGE8 in vascular endothelium in rats with experimental SAH and controls, together with the applications of RNA silencing and pharmacological intervention methods. Relative to control, recombinant human MFGE8 (rhMFGE8) treatment increased 5-bromo-2'-deoxyuridine (BrdU) labeled new endothelial cells, reduced TUNUL-positive endothelial cells and elevated the expression of phosphatidylinositol 3-kinase (PI3K) and chemokine (C-X-C motif) ligand 12 (CXCL12), in the brains of SAH rats. These effects were reversed by MFGE8 RNA silencing, as well as following cilengitide and wortmannin intervention. These results suggest that MFGE8 promotes endothelial regeneration and mitigates endothelial DNA damage through the activation of the TIGβ5/PI3K/CXCL12 signaling pathway.
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http://dx.doi.org/10.1007/s00221-021-06111-xDOI Listing
May 2021

A magneto-fluorescence bacteria assay strategy based on dual colour sulfide fluorescent nanoparticles with high near-IR conversion efficiency.

Analyst 2020 Jul 29;145(13):4436-4441. Epub 2020 May 29.

State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Hunan University, Changsha 410082, Hunan, China.

Anti-Stokes fluorescence induced by near-IR (NIR) radiation is particularly advantageous for the bioassay of complex samples, but most of the commonly used NIR-induced fluorescence nanomaterials such as up-conversion nanoparticles (UCNPs) do not exhibit satisfactory fluorescence intensity and work against achieving a highly sensitive bioassay. In this study, we a construct sensitive and specific bacteria biosensor based on the NIR-stimulated CaS: Eu, Sm, Mn and SrS: Ce, Sm, Mn nanoparticles. The fluorescent nanoparticles are conjugated with bacteria recognition fragments. In addition, the independent emission bands of these two types of fluorescent nanoparticles make it possible to detect and quantify Gram-positive strain and Gram-negative strain, simultaneously. Intense fluorescence and magnetic enrichment of magneto-fluorescence systems enable bacteria discrimination with the naked eye and improve sensitivity in trace bacteria detection (<20 CFU mL). The linear relationship between the fluorescence intensity and bacterial concentration is established with a detection range of 25-10 CFU mL. Furthermore, this NIR-excited assay strategy demonstrates better anti-interference capability than UV/visible-excited assay methods, showing high potential and practical value for medical diagnostics and bacteria monitoring.
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http://dx.doi.org/10.1039/d0an00816hDOI Listing
July 2020

Occurrence and risk assessment of 3- and 2-monochloropropanediol (MCPD) esters in vegetable oils and related products from Zhejiang market.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2020 Jun 2;37(6):931-937. Epub 2020 Apr 2.

Department of Nutrition & Food Safety, Zhejiang Provincial Center for Disease Control and Prevention , Hangzhou, PR China.

3- And 2-monochloropropanediol fatty acid esters (3- and 2-MCPD esters) are contaminants of processed vegetable oils. In this study, vegetable oils and related products available 486 food samples from Zhejiang market were collected and analysed for 3- and 2-MCPD esters during 2016-2018. Food consumption data were taken from a food consumption survey of urban and rural residents in Zhejiang province performed in 2008 using data from 9646 subjects. Levels of 3-MCPD esters in foods ranged from not detected to 8.3 mg/kg, and the highest mean levels were found in vegetable oils with levels of 0.76 mg/kg. Esters of 2-MCPD levels ranged from not detected to 4.0 mg/kg, and the highest mean levels were found in instant noodles containing 0.40 mg/kg. The dietary intake of 3-MCPD was 0.62 μg/kg bw per day (mean) and 2.29 μg/kg bw per day (P97.5), and 2-MCPD esters intakes were 0.26 μg/kg bw per day (mean) and 0.87 μg/kg bw per day (P97.5). Vegetable oils were the main food source of dietary 3- and 2-MCPD esters intake. These findings suggested that the dietary exposure levels of 3-MCPD esters may pose a potential risk to the health for high consumers (P97.5) aged 4-17 when compared to the tolerable daily intake.
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http://dx.doi.org/10.1080/19440049.2020.1745298DOI Listing
June 2020

Recombinant Human Milk Fat Globule-Epidermal Growth Factor 8 Attenuates Microthrombosis after Subarachnoid Hemorrhage in Rats.

J Stroke Cerebrovasc Dis 2020 Mar 26;29(3):104536. Epub 2019 Dec 26.

Department of Neurosurgery, Third XiangYa Hospital, Central South University, Changsha, Hunan, China. Electronic address:

Background: Microthrombosis after subarachnoid hemorrhage has an adverse effect on prognosis. Milk fat globule-epidermal growth factor 8 promotes phagocytosis of phagocytic cells and may reduce microthrombosis. This study investigated the effects of recombinant human milk fat globule-epidermal growth factor 8 on microthrombosis and neurological function after subarachnoid hemorrhage.

Methods: Rats subarachnoid hemorrhage model was induced by intravascular puncture method. Western blot was performed to measure the expression of endogenous milk fat globule-epidermal growth factor 8 after subarachnoid hemorrhage. Microthrombosis was quantified by microthrombi count using immunohistochemistry and immunofluorescence. The neuroprotective effect of recombinant human milk fat globule-epidermal growth factor 8 administration was evaluated by modified Garcia score, beam balance, Rotarod test, and Morris water maze.

Results: Endogenous milk fat globule-epidermal growth factor 8 protein level increased after subarachnoid hemorrhage. Microthrombosis was significantly increased in subarachnoid hemorrhage rats brain, while recombinant human milk fat globule-epidermal growth factor 8 dramatically reduced microthrombosis as well as improve short- and long- term neurobehavior after subarachnoid hemorrhage.

Conclusions: Recombinant human milk fat globule-epidermal growth factor 8 reduces microthrombosis and improves neurological function after subarachnoid hemorrhage, which may be an effective strategy for treating subarachnoid hemorrhage.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2019.104536DOI Listing
March 2020

Multicolor lanthanide-doped CaS and SrS near-infrared stimulated luminescent nanoparticles with bright emission: application in broad-spectrum lighting, information coding, and bio-imaging.

Nanoscale 2019 Jul 25;11(26):12497-12501. Epub 2019 Jun 25.

State Key Laboratory of Chem/Bio-sensing and Chemometrics, Hunan University, Changsha 410082, P. R. China.

A series of lanthanide-doped CaS and SrS nanoparticles possessing bright fluorescence under near-infrared light (NIR) illumination and tunable emission colors are prepared and applied in light emitting, information coding, cell-labeling and in vivo imaging. The high fluorescence intensity and easily tunable emission wavelength under 980 nm light excitation make these multicolor alkaline earth sulfide nanoparticles (AES NPs) good in vivo biolabels for simultaneous differentiation of multiple organs, and other NIR-excitation-based applications.
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http://dx.doi.org/10.1039/c9nr03421hDOI Listing
July 2019

Inhibition of Heat Shock Protein 90 by 17-AAG Reduces Inflammation via P2X7 Receptor/NLRP3 Inflammasome Pathway and Increases Neurogenesis After Subarachnoid Hemorrhage in Mice.

Front Mol Neurosci 2018 6;11:401. Epub 2018 Nov 6.

Department of Neurosurgery, Third XiangYa Hospital, Central South University, Changsha, China.

Subarachnoid hemorrhage (SAH) is a life-threatening cerebrovascular disease that usually has a poor prognosis. Heat shock proteins (HSPs) have been implicated in the mechanisms of SAH-associated damage, including increased inflammation and reduced neurogenesis. The aim of this study was to investigate the effects of HSP90 inhibition on inflammation and neurogenesis in a mouse model of experimental SAH induced by endovascular surgery. Western blotting showed HSP90 levels to be decreased, while neurogenesis, evaluated by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry, was decreased in the hippocampuses of SAH mice. SAH also induced pro-inflammatory factors such as interleukin-1β (IL-1β), capase-1 and the NLRP3 inflammasome. However, intraperitoneal administration of the specific HSP90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) reduced the levels of HSP90, NLRP3, ASC, caspase-1 and IL-1β, while increasing the levels of brain-derived neurotrophic factor and doublecortin (DCX), as well as the number of BrdU-positive cells in SAH mice. In addition, 17-AGG improved short- and long-term neurobehavioral outcomes. The neuroprotective and anti-inflammatory effects of 17-AGG were reversed by recombinant HSP90 (rHSP90); this detrimental effect of HSP90 was inhibited by the specific P2X7 receptor (P2X7R) inhibitor A438079, indicating that SAH-induced inflammation and inhibition of neurogenesis were likely mediated by HSP90 and the P2X7R/NLRP3 inflammasome pathway. HSP90 inhibition by 17-AAG may be a promising therapeutic strategy for the treatment of SAH.
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http://dx.doi.org/10.3389/fnmol.2018.00401DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6232389PMC
November 2018

Neurogenesis changes and the fate of progenitor cells after subarachnoid hemorrhage in rats.

Exp Neurol 2019 01 23;311:274-284. Epub 2018 Oct 23.

Department of Neurosurgery, The third XiangYa Hospital, Central South University, Changsha 410013, China. Electronic address:

Background: Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease that leads to poor outcomes. Neurogenesis, an essential recovery mechanism after brain injury, has not been fully elucidated after SAH.

Methods: A total of 122 SD rats were used in this study. For experiment one, the rats were randomly divided into six groups: sham and SAH with different time points (1,3,5,7,14 days) (n = 12/group). An endovascular perforation method was conducted for SAH model. Rats were injected with 5-Bromo-2'-deoxyuridine (BrdU, 50 mg/kg) 24 h before euthanasia at different time points after SAH. The BrdU labeled cells were detected by immunohistochemistry; Doublecortin (DCX) and glial fibrillary acidic protein (GFAP) were measured by western blot and immunohistochemistry. For experiment two, rats were randomly divided into five groups: sham and SAH with different time points (1, 2, 4, 8 weeks) (n = 6/group). Rats received BrdU (50 mg/kg) once daily for 7 days after the induction of SAH. Double immunofluorescence staining was used to verify proliferation, differentiation and migration of progenitor cells. Rotarod test and water maze used to test the neurobehavioral recovery.

Results: Our results showed that BrdU positive cells in hippocampus changed overtime after SAH. BrdU positive cells decreased as early as 1 day reaching lowest levels at 3 days after SAH, after which it gradually recovered. Similar change patterns were observed with DCX, which was reversed with GFAP. In addition, BrdU did not co-localize with cleaved caspase-3. The BrdU positive cells mainly differentiated into immature neurons for short-term fate, whereas they differentiated into mature neurons for long-term fate but not astrocytes, which facilitated neurobehavioral recovery after SAH.

Conclusion: Neurogenesis in the hippocampus changes overtime after SAH. The neuronal progenitor cells may play an essential role in the neurobehavioral recovery after brain injury induced by SAH, since short-term progenitors helped with the recovery of immature neurons in the hippocampus, whereas long-term progenitors differentiated into mature neurons.
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http://dx.doi.org/10.1016/j.expneurol.2018.10.011DOI Listing
January 2019

Hyperuniformity with no fine tuning in sheared sedimenting suspensions.

Nat Commun 2018 07 19;9(1):2836. Epub 2018 Jul 19.

Department of Physics and Soft and Living Matter Program, Syracuse University, Syracuse, NY, 13244, USA.

Particle suspensions, present in many natural and industrial settings, typically contain aggregates or other microstructures that can complicate macroscopic flow behaviors and damage processing equipment. Recent work found that applying uniform periodic shear near a critical transition can reduce fluctuations in the particle concentration across all length scales, leading to a hyperuniform state. However, this strategy for homogenization requires fine tuning of the strain amplitude. Here we show that in a model of sedimenting particles under periodic shear, there is a well-defined regime at low sedimentation speed where hyperuniform scaling automatically occurs. Our simulations and theoretical arguments show that the homogenization extends up to a finite length scale that diverges as the sedimentation speed approaches zero.
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http://dx.doi.org/10.1038/s41467-018-05195-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6053396PMC
July 2018

Eu,Sm,Mn-Doped CaS Nanoparticles with 59.3% Upconversion-Luminescence Quantum Yield: Enabling Ultrasensitive and Facile Smartphone-Based Sulfite Detection.

Anal Chem 2018 07 6;90(14):8658-8664. Epub 2018 Jul 6.

State Key Laboratory of Chem/Bio-sensing and Chemometrics , Hunan University , Changsha 410082 , P. R. China.

Eu,Sm,Mn-doped CaS (ESM-CaS) nanoparticles demonstrate a remarkable upconversion luminescence (UCL) efficiency with a quantum yield of nearly 60%, enabling many new applications and devices. We describe an ESM-CaS nanoparticle-based paper test strip for one-shot quantitative measurement of sulfite concentration using a smartphone-based reader. The integrated UCL-based sulfite detection system features high sensitivity and facile operation without the need for separation and pretreatment. Moreover, the design principles are general in nature and so can be tailored for the detection and quantification of a variety of other analytes.
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http://dx.doi.org/10.1021/acs.analchem.8b02001DOI Listing
July 2018

Highly-luminescent Eu,Sm,Mn-doped CaS up/down conversion nano-particles: application to ultra-sensitive latent fingerprint detection and in vivo bioimaging.

Chem Commun (Camb) 2018 Jan;54(6):591-594

State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, China.

Due to their unique properties, rare-earth doped upconversion luminescence (UCL) nanomaterials are of considerable scientific interest. Meanwhile, alkaline-earth sulfide materials based on a completely different electron trapping (ET) mechanism demonstrate extremely high UCL efficiencies, which are several dozens of times more than those of conventional fluoride UCL nanomaterials. However, the large particle size, easy hydrolysis, and difficulty in achieving uniform dispersion have precluded bioassay applications. Herein, we have synthesized super-bright Eu,Sm,Mn-doped CaS nanoparticles of ∼30 nm average particle size using a reverse microemulsion technique. The UCL quantum yield was up to nearly 60%. Modification of the nanoparticles with an organic layer allows their stable dispersion throughout aqueous solutions without significant loss of the fluorescence intensity. We demonstrate the application of the novel UCL materials to latent fingerprint detection, deep tissue imaging, and in vivo bioimaging.
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http://dx.doi.org/10.1039/c7cc07790dDOI Listing
January 2018