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Space-confined twin-polymerization enabling homogeneous integration of ultrafine TiO 2 nanoparticles into a sulfur-doped carbon matrix for boosting lithium storage. Chem Commun (Camb) 2024. [PMID: 38456200 DOI: 10.1039/d4cc00765d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
Homogeneous integration of ultrafine TiO2 nanoparticles into a conductive sulfur-doped carbon skeleton was readily crafted by unusual space-confined twin-polymerization of a titanium-containing single-source coupled monomer and subsequent carbonization, producing a robust hetero-architecture for boosting lithium storage with large reversible capacity, high rate capability, and long-term cycling stability.
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Pathological features and molecular signatures of early olfactory dysfunction in 3xTg-AD model mice. CNS Neurosci Ther 2024; 30:e14632. [PMID: 38366763 PMCID: PMC10873683 DOI: 10.1111/cns.14632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 01/18/2024] [Accepted: 01/30/2024] [Indexed: 02/18/2024] Open
Abstract
BACKGROUND Olfactory dysfunction is known to be an early manifestation of Alzheimer's disease (AD). However, the underlying mechanism, particularly the specific molecular events that occur during the early stages of olfactory disorders, remains unclear. METHODS In this study, we utilized transcriptomic sequencing, bioinformatics analysis, and biochemical detection to investigate the specific pathological and molecular characteristics of the olfactory bulb (OB) in 4-month-old male triple transgenic 3xTg-AD mice (PS1M146V/APPSwe/TauP301L). RESULTS Initially, during the early stages of olfactory impairment, no significant learning and memory deficits were observed. Correspondingly, we observed significant accumulation of amyloid-beta (Aβ) and Tau pathology specifically in the OB, but not in the hippocampus. In addition, significant axonal morphological defects were detected in the olfactory bulb, cortex, and hippocampal brain regions of 3xTg-AD mice. Transcriptomic analysis revealed a significant increase in the expression of neuroinflammation-related genes, accompanied by a significant decrease in neuronal activity-related genes in the OB. Moreover, immunofluorescence and immunoblotting demonstrated an activation of glial cell biomarkers Iba1 and GFAP, along with a reduction in the expression levels of neuronal activity-related molecules Nr4a2 and FosB, as well as olfaction-related marker OMP. CONCLUSION In sum, the early accumulation of Aβ and Tau pathology induces neuroinflammation, which subsequently leads to a decrease in neuronal activity within the OB, causing axonal transport deficits that contribute to olfactory disorders. Nr4a2 and FosB appear to be promising targets for intervention aimed at improving early olfactory impairment in AD.
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Integrated transcriptomics reveals the brain and blood biomarkers in Alzheimer's disease. CNS Neurosci Ther 2023; 29:3943-3951. [PMID: 37334737 PMCID: PMC10651972 DOI: 10.1111/cns.14316] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/20/2023] Open
Abstract
BACKGROUND The systematic molecular associations between the peripheral blood cells and brain in Alzheimer's disease (AD) remains unclear, which hinders our understanding of AD pathological mechanisms and the exploration of new diagnostic biomarkers. METHODS Here, we performed an integrated analysis of the brain and peripheral blood cells transcriptomics to establish peripheral biomarkers of AD. By employing multiple statistical analyses plus machine learning, we identified and validated multiple regulated central and peripheral network in patients with AD. RESULTS By bioinformatics analysis, a total of 243 genes were differentially expressed in the central and peripheral systems, mainly enriched in three modules: immune response, glucose metabolism and lysosome. In addition, lysosome related gene ATP6V1E1 and immune response related genes (IL2RG, OSM, EVI2B TNFRSF1A, CXCR4, STAT5A) were significantly correlated with Aβ or Tau pathology. Finally, receiver operating characteristic (ROC) analysis revealed that ATP6V1E1 showed high-diagnostic potential for AD. CONCLUSION Taken together, our data identified the main pathological pathways in AD progression, particularly the systemic dysregulation of the immune response, and provided peripheral biomarkers for AD diagnosis.
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Facile Fabrication of Superhydrophobic and Flame-Retardant Coatings on Cotton Fabrics. Polymers (Basel) 2022; 14:polym14235314. [PMID: 36501707 PMCID: PMC9736095 DOI: 10.3390/polym14235314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
The hydrophilicity and inherent flammability of cotton textiles severely limit their usage. To solve these drawbacks, a superhydrophobic and flame-retardant (SFR) coating made of chitosan (CH), ammonium polyphosphate (APP), and TiO2-SiO2-HMDS composite was applied to cotton fabric using simple layer-by-layer assembly and dip-coating procedures. First, the fabric was alternately immersed in CH and APP water dispersions, and then immersed in TiO2-SiO2-HMDS composite to form a CH/APP@TiO2-SiO2-HMDS coating on the cotton fabric surface. SEM, EDS, and FTIR were used to analyze the surface morphology, element composition, and functional groups of the cotton fabric, respectively. Vertical burning tests, microscale combustion calorimeter tests, and thermogravimetric analyses were used to evaluate the flammability, combustion behavior, thermal degradation characteristics, and flame-retardant mechanism of this system. When compared to the pristine cotton sample, the deposition of CH and APP enhanced the flame retardancy, residual char, heat release rate, and total heat release of the cotton textiles. The superhydrophobic test results showed that the maximal contact angle of SFR cotton fabric was 153.7°, and possessed excellent superhydrophobicity. Meanwhile, the superhydrophobicity is not lost after 10 laundering cycles or 50 friction cycles. In addition, the UPF value of CH/APP@TiO2-SiO2-HMDS cotton was 825.81, demonstrating excellent UV-shielding properties. Such a durable SFR fabric with a facile fabrication process exhibits potential applications for both oil/water separation and flame retardancy.
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Yeast cell wall product enhanced intestinal IgA response and changed cecum microflora species after oral vaccination in chickens. Poult Sci 2020; 99:6576-6585. [PMID: 33248573 PMCID: PMC7705035 DOI: 10.1016/j.psj.2020.09.075] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 09/15/2020] [Accepted: 09/23/2020] [Indexed: 11/25/2022] Open
Abstract
The study was designed to explore the effect of a commercial yeast cell wall product (YP) on chicken intestinal IgA response and cecum microbiome after oral vaccination. Chickens were fed with YP during the experiments and orally immunized with live Newcastle disease virus (NDV) vaccine at 2 wk of age. Then, the animals were sacrificed, and samples were collected to measure the indicators of hemagglutination inhibition (HI), IgA response, IgA + cells, and cecum microbiome populations. The results showed that supplement of YP significantly enhanced serum NDV HI titer, intestinal NDV-specific secretory IgA, and intestinal IgA + cells. The sequencing results revealed that obviously increased relative abundance of Ruminococcaceae and decreased population of Bacteroidaceae in cecum were found in YP group. In summary, YP supplementation in diet enhanced intestinal IgA response to NDV vaccination by oral route and modulated the cecum microbiota to the advantage of the host in chickens.
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Highly Stretchable Sheath-Core Yarns for Multifunctional Wearable Electronics. ACS APPLIED MATERIALS & INTERFACES 2020; 12:29717-29727. [PMID: 32517469 DOI: 10.1021/acsami.0c08840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Flexible electronic devices with strain sensing and energy storage functions integrated simultaneously are urgently desirable to detect human motions for potential wearable applications. This paper reports the fabrication of a cotton/carbon nanotube sheath-core yarn deposited with polypyrrole (PPy) for highly multifunctional stretchable wearable electronics. The microscopic structure and morphology of the prepared sheath-core yarn were characterized by scanning electron microscopy and Fourier transform infrared spectrometry. A mechanical experiment demonstrated its excellent stretchable capacity because of its unique spring-like structure. We demonstrate that the sheath-core yarn can be used as wearable strain sensors, exhibiting an ultrahigh strain sensing range (0-350%) and excellent stability. The sheath-core yarn can be used in highly sensitive real time monitoring toward both subtle and large human motions under different conditions. Furthermore, the electrochemical performance of the sheath-core yarn was characterized by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. The measured areal capacitance was 761.2 mF/cm2 at the scanning rate of 1 mV/s. The method of spinning technology may lead to new exploitation of CNTs and PPy in future wearable electronic device applications.
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Incorporating silica-coated graphene in bioceramic nanocomposites to simultaneously enhance mechanical and biological performance. J Biomed Mater Res A 2020; 108:1016-1027. [PMID: 31925910 DOI: 10.1002/jbm.a.36880] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 12/28/2019] [Accepted: 12/31/2019] [Indexed: 11/06/2022]
Abstract
The applications of a variety of bioactive ceramics such as hydroxyapatite (HA) in orthopedics are limited by their insufficient mechanical properties, especially poor fracture toughness. Thus, further extending the clinical applications of these materials warrants the enhancement of their mechanical properties. Although the reinforcement of ceramics by 2D nanomaterials has been well recognized, integrated structural, mechanical, and functional considerations have been neglected in the design and synthesis of such composite materials. Herein, we report the first use of silica-coated reduced graphene oxide (S-rGO) hybrid nanosheets to create bioceramic-based composites with simultaneously enhanced mechanical and biological properties. In the representative HA-based bioceramic systems prepared by spark plasma sintering, S-rGO incorporation was found to be more effective for increasing the Young's modulus, hardness, and fracture toughness than the incorporation of uncoated reduced GO (rGO). Furthermore, when assessed with osteoblast-like MG-63 cells, such novel materials led to faster cell proliferation and higher cell viability and alkaline phosphatase activity than are generally observed with pure HA; additionally, cells demonstrate stronger affinity to S-rGO/HA than to rGO/HA composites. The S-rGO/bioceramic composites are therefore promising for applications in orthopedic tissue engineering, and this research provides valuable insights into the fabrication of silica-coated hybrid nanosheet-reinforced ceramics.
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Combined adjuvant effect of ginseng stem-leaf saponins and selenium on immune responses to a live bivalent vaccine of Newcastle disease virus and infectious bronchitis virus in chickens. Poult Sci 2019; 98:3548-3556. [PMID: 31220864 PMCID: PMC7107245 DOI: 10.3382/ps/pez207] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 03/24/2019] [Indexed: 12/12/2022] Open
Abstract
Vaccination with a live bivalent vaccine of Newcastle disease virus (NDV) and infectious bronchitis virus (IBV) is a routine practice in poultry industry in China. This study was designed to evaluate ginseng stem-leaf saponins (GSLS) in combination with selenium (Se) for their adjuvant effect on the immune response to vaccination against NDV and IBV in chickens. A live bivalent vaccine of NDV and IBV was diluted in saline solution containing GSLS or Se or both and used to immunize chickens via a intraocular-and-intranasal route. Results showed that GSLS promoted significantly higher NDV- and IBV-specific antibody responses with the highest antibody response detected in GSLS-Se group. The increased antibody was capable of neutralizing NDV and IBV. In addition, GSLS-Se enhanced lymphocyte proliferation and production of IFN-γ and IL-4. More importantly GSLS-Se was found to promote early production and prolong the duration of the antibody responses. In order to improve the efficacy of vaccination in chicken flocks, the diluent containing GSLS-Se deserves further studies to evaluate its effect on other chicken vaccines.
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Abstract
Structural analysis showed that cyclosiloxane hybrid polymer (CHP) is a collection of nano-sized nacre-like structures in random orientations. Inspired by the reinforcement of nacre-like materials, basal-functionalized graphene (GO-AA) was inserted between CHP layers, acting as 'double-sided tape' to improve the mechanical properties. The resulting GO-AA/CHP nanocomposites showed a 156% improvement in toughness with only a 0.08 wt% loading of GO-AA, and a 25% improvement in thermal conductivity with a 0.10 wt% loading of GO-AA. The proposed 'double-sided tape' effect was also used to explain the highly efficient enhancement in thermal conductivity. This research promotes the application of CHP in harsher environments, demonstrates its prospects in thermal management areas, and contributes to nature-inspired materials design.
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Ginsenoside Rg1 enhanced immune responses to infectious bursal disease vaccine in chickens with oxidative stress induced by cyclophosphamide. Poult Sci 2018; 97:2698-2707. [PMID: 29660049 DOI: 10.3382/ps/pey132] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 03/19/2018] [Indexed: 11/20/2022] Open
Abstract
This study was designed to evaluate the effect of oral administration of ginsenoside Rg1 on oxidative stress induced by cyclophosphamide in chickens. Ninety-six chickens were randomly divided into 4 groups, each consisting of 24 birds. Groups 2 and 3 received intramuscular injection of cyclophosphamide at 100 mg/kg body weight for 3 d to induce oxidative stress and immune suppression. Groups 1 and 4 were injected with saline in the same way as groups 2 and 3. Then chickens in group 3 were orally administrated Rg1 of 1 mg/kg body weight in drinking water for 7 d. After that, groups 1 to 3 were orally vaccinated with attenuated infectious bursal disease vaccine (Strain B87). Blood samples were collected for determination of infectious bursal disease virus-specific antibodies, cytokines, and oxidative parameters. Splenocytes were prepared for lymphocyte proliferation assay. The results showed that oral administration of ginsenoside Rg1 significantly enhanced specific antibody, IFN-γ, and IL-6 responses, and lymphocyte proliferation induced by concanavalin A and lipopolysaccharide in chickens injected with cyclophosphamide. Antioxidant activity of ginsenoside Rg1 was also observed in chickens by increased total antioxidant capacity, total superoxide dismutase, catalase, glutathione peroxidase, glutathione, ascorbic acid, and α-tocopherol, as well as decreased malondialdehyde and protein carbonyl. Therefore, oral administration of Rg1 was shown to improve the immune responses to infectious bursal disease vaccine in chickens suffering from oxidative stress.
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Downregulation of hsa_circ_0000285 serves as a prognostic biomarker for bladder cancer and is involved in cisplatin resistance. Neoplasma 2018; 66:197-202. [PMID: 30509102 DOI: 10.4149/neo_2018_180318n185] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 07/16/2018] [Indexed: 11/08/2022]
Abstract
Bladder cancer remains a very challenging disease to treat with the high rates of recurrence and progression associated with current therapies. Although the association between bladder cancer pathology and circRNAs remains undetermined, circRNAs signatures may be useful as prognostic and predictive factors and clinical tools for assessing disease state, treatment response and outcome. This study investigates if these circRNAs can be used as biomarkers for bladder cancer diagnosis and predicting treatment response. Herein, qPCR measured the expression of hsa_circRNA_100783, hsa_circ_0000285 and hsa_circRNA_100782 in bladder cancer tissues. It was established that sa_circ_0000285, but not hsa_circRNA_100782 and hsa_circRNA_10078, are significantly reduced in bladder cancer tissues and serum compared to adjacent tissues and healthy controls. Moreover, hsa_circ_0000285 expression was lower in cisplatin-resistant bladder cancer patients than in those who were cisplatin-sensitive. Here, hsa_circ_0000285 was associated with tumor size (p<0.001), differentiation (p<0.001), lymph node metastasis (p=0.038), distant metastasis (p=0.004) and TNM stage (p=0.013). Further analysis showed that hsa_circ_0000285 would be an independent prognostic factor for bladder cancer patient outcome. In conclusion, our study indicates hsa_circ_0000285 may be a novel biomarker for bladder cancer because of its involvement in bladder cancer chemo-sensitivity.
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Abstract
The present study was designed to evaluate the effects of tea saponins on oxidative stress induced by cyclophosphamide in chickens. One hundred twenty chickens were randomly divided into 5 groups. Groups 3 to 4 received intramuscular injection of cyclophosphamide to induce oxidative stress and immunosuppression. After that, groups 2 and 4 were orally administered tea saponins in drinking water for 7 d. Then, groups 1 to 4 were immunized with a live, bivalent vaccine of Newcastle disease virus and infectious bronchitis virus. Blood samples were collected for analysis of oxidative parameters and specific antibody titers, and splenocytes were prepared for lymphocyte proliferative assay. The results showed that administration of tea saponins significantly increased total antioxidant capacity, total superoxide dismutase, catalase, glutathione peroxidase, glutathione, ascorbic acid, and α-tocopherol, and decreased malondialdehyde and protein carbonyl. Enhanced immune responses, such as lymphocyte proliferation induced by concanavalin A and lipopolysaccharides, and serum Newcastle disease virus- and infectious bronchitis virus-specific antibodies were also observed in chickens injected with or without cyclophosphamide. In addition, no side effects were found in chickens throughout the study. Therefore, tea saponins may be a potential agent to improve imunosuppression induced by oxidative stress in chickens.
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Precisely Tuning Helical Twisting Power via Photoisomerization Kinetics of Dopants in Chiral Nematic Liquid Crystals. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:700-708. [PMID: 29268613 DOI: 10.1021/acs.langmuir.7b03786] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
It has been paid much attention to improve the helical twisting power (β) of dopants in chiral nematic liquid crystals (CLCs); however, the correlations between the β value and the molecular structures as well as the interaction with nematic LCs are far from clear. In this work, a series of reversibly photo-switchable axially chiral dopants with different lengths of alkyl or alkoxyl substituent groups have been successfully synthesized through nucleophilic substitution and the thiol-ene click reaction. Then, the effect of miscibility between these dopants and nematic LCs on the β values, as well as the time-dependent decay/growth of the β values upon irradiations, has been investigated. The theoretical Teas solubility parameter shows that the miscibility between dopants and nematic LCs decreases with increasing of the length of substituent groups from dopant 1 to dopant 4. The β value of chiral dopants in nematic LCs decreases from dopant 1 to dopant 4 both at the visible light photostationary state (PSS) and at the UV PSS after UV irradiation. With increasing of the length of substituent groups, the photoisomerization rate constant of dopants increases for trans-cis transformation upon UV irradiation and decreases for the reverse process upon visible light irradiation either in isotropic ethyl acetate or in anisotropic LCs, although the constant in ethyl acetate is several times larger than the corresponding value in LCs. Also, the color of the CLCs could be tuned upon light irradiations. These results enable the precise tuning of the pitch and selective reflection wavelength/color of CLCs, which paves the way to the applications in electro-optic devices, information storage, high-tech anticounterfeit, and so forth.
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PROTECTIVE FACTORS IN VULNERABLE, RURAL OLDER ADULTS: LINKS WITH SALIVARY MARKERS OF INFLAMMATION. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.1148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Regulatory mechanism of miR-29 over TGF-β1 and COL1 in scar cells. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2017; 21:2512-2517. [PMID: 28617563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To study the regulatory mechanism of miR-29 over TGF-β1 and COL1 in scar cells. PATIENTS AND METHODS 5 clinical cases of hypertrophic scar (HS) skin and adjacent normal skin tissues were separated into fibroblast for primary culture and subculture before being observed morphologically and standard HE staining under an ordinary optical microscope. RT-PCR method was applied to test the expression level of miR-29, TGF-β1, and COL1 mRNA. ELISA method was applied to test the expression level of extracellular matrix COL1, fibronectin (FN) and α-SMA. The miR-29 overexpression vector was built and transfected in vitro. RT-PCR method was applied to test related genes and ELISA method was applied to test the expression level of the extracellular matrix. RESULTS The color of karyon and cytoplasm of normal fibroblast were both light red, with little ECM. The color of karyon of scar fibroblast was blue. The cytoplasm was red of different degrees, with relatively much ECM, in deep blue color. Compared with that in the normal fibroblast group, the miR-29 mRNA in fibroblast in the scar group significantly decreased (p<0.05). The TGF-β1 and COL1 mRNA significantly increased (p<0.05). The COL1, FN and α-SMA level were significantly higher (p<0.05) than that in the normal group. These mRNAs levels in miR-29 overexpression group were lower than scar group but higher than the normal group. CONCLUSIONS The expression of miR-29 which regulates the expression of TGF-β1 and COL1 and increases the level of ECM significantly decreases in scar cells. This one suggests a mechanism of the formation of the scars through TGF-β1 and COL1.
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Ultrahigh Self-Sensing Performance of Geopolymer Nanocomposites via Unique Interface Engineering. ACS APPLIED MATERIALS & INTERFACES 2017; 9:12851-12858. [PMID: 28333431 DOI: 10.1021/acsami.7b00419] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Monitoring and assessment of the health of a civil structural material are the critical requirements to ensure its safety and durability. In this work, a coating strategy on carbon nanotubes (CNTs) was employed for the dispersion of CNTs in geopolymer matrix. The geopolymer nanocomposites prepared exhibited ultrahigh self-sensing performance based on the unique behaviors of SiO2 coating on CNTs in the geopolymer matrix. The SiO2 layer on CNTs was partially or fully removed during the fabrication process to restore the conductive nature of CNTs, facilitating the dispersion of CNTs and forming well-connected 3D electrical conductive networks. The gauge factor (GF) of geopolymer nanocomposites reached up to 663.3 and 724.6, under compressive and flexural loading, respectively, with the addition of only 0.25 vol % of SiO2-coated CNTs (SiO2-CNTs). The values were at least twice higher than those recently reported self-sensing structural materials containing different types of carbon-based fillers. The underlying mechanisms on the electrical signal change with respect to ionic conduction and electronic conduction were explored and correlated to the self-sensing performance. Additionally, the uniform dispersion of CNTs and good interaction between CNTs and geopolymer matrix contributed to the improvement in flexural and compressive strengths.
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A comparative study on electromagnetic interference shielding behaviors of chemically reduced and thermally reduced graphene aerogels. J Colloid Interface Sci 2017; 492:112-118. [DOI: 10.1016/j.jcis.2016.12.060] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/22/2016] [Accepted: 12/25/2016] [Indexed: 12/25/2022]
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A Dual-Responsive Nanocomposite toward Climate-Adaptable Solar Modulation for Energy-Saving Smart Windows. ACS APPLIED MATERIALS & INTERFACES 2017; 9:6054-6063. [PMID: 28112905 DOI: 10.1021/acsami.6b15065] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In this work, a novel fully autonomous photothermotropic material made by hybridization of the poly(N-isopropylacrylamide) (PNIPAM) hydrogel and antimony-tin oxide (ATO) is presented. In this photothermotropic system, the near-infrared (NIR)-absorbing ATO acts as nanoheater to induce the optical switching of the hydrogel. Such a new passive smart window is characterized by excellent NIR shielding, a photothermally activated switching mechanism, enhanced response speed, and solar modulation ability. Systems with 0, 5, 10, and 15 atom % Sb-doped ATO in PNIPAM were investigated, and it was found that a PNIPAM/ATO nanocomposite is able to be photothermally activated. The 10 atom % Sb-doped PNIPAM/ATO exhibits the best response speed and solar modulation ability. Different film thicknesses and ATO contents will affect the response rate and solar modulation ability. Structural stability tests at 15 cycles under continuous exposure to solar irradiation at 1 sun intensity demonstrated the performance stability of such a photothermotropic system. We conclude that such a novel photothermotropic hybrid can be used as a new generation of autonomous passive smart windows for climate-adaptable solar modulation.
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Assessing the impact of a program for late surgical intervention in early-blind children. Public Health 2017; 146:15-23. [PMID: 28404468 DOI: 10.1016/j.puhe.2016.12.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 12/12/2016] [Accepted: 12/20/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Many blind children in the developing world are unable to obtain timely treatment due to lack of financial and medical resources. Can public health programs that identify and treat such children several years after the onset of blindness enhance their quality of life? The notion that visual development is subject to an early 'critical period' argues against this possibility. However, there are inadequate empirical data from humans on this issue. To address this need, we examined the quality of life of children living in India and who were treated for early-onset blindness (before one year of age), due to cataracts or corneal opacities. STUDY DESIGN Survey study. METHODS As part of an ongoing scientific effort named Project Prakash, we screened over 40,000 children in rural northern India to identify those suffering from early-onset blindness. They were provided eye surgeries in a tertiary care ophthalmic center in New Delhi. We subsequently surveyed 64 Prakash children, ranging in age from 5 to 22 years and obtained their responses on a multi-dimensional quality of life questionnaire. RESULTS Nearly all of the subjects indicated that their quality of life had improved after treatment. Children reported marked enhancement in their mobility, independence, and safety, and also in social integration. Surprisingly, we found no significant correlations between quality of life metrics and factors such as age at treatment, gender, time since treatment, and pre-surgery and post-surgery acuity. CONCLUSIONS A key question for public health policy makers is whether a program of surgical intervention for older blind children is likely to be beneficial, or if the resources are better spent on rehabilitation via vocational training and assistive devices. The marked improvements in quality of life we find in our data strongly argue for the provision of surgical care regardless of a child's age.
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Functional Piglet Model for the Clinical Syndrome and Postmortem Findings Induced by Staphylococcal Enterotoxin B. Exp Biol Med (Maywood) 2016; 229:1061-71. [PMID: 15522843 DOI: 10.1177/153537020422901011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Staphylococcal enterotoxin (SE) B causes serious gastrointestinal illness, and intoxication with this exotoxin can lead to lethal toxic shock syndrome. In order to overcome significant shortcomings of current rodent and nonhuman primate models, we developed a piglet model of lethal SEB intoxication. Fourteen-day-old Yorkshire piglets were given intravenous SEB, observed clinically, and sacrificed at 4, 6, 24, 48, 72, or 96 hrs posttreatment. Clinical signs were biphasic with pyrexia, vomiting, and diarrhea within 4 hrs, followed by terminal hypotension and shock by 96 hrs. Mild lymphoid lesions were identified as early as 24 hrs, with severe lymphadenopathy, splenomegaly, and prominent Peyer's patches found by 72 hrs. Widespread edema—most prominent in the mesentery, between loops of spiral colon, and in retroperitoneal connective tissue—was found in animals at 72 hrs. Additional histologic changes included perivascular aggregates of large lymphocytes variably present in the lung and brain, circulating lymphoblasts, and lymphocytic portal hepatitis. Preliminary molecular investigation using gene array has uncovered several gene profile changes that may have implications in the pathophysiology leading to irreversible shock. Five genes were selected for further study, and all showed increased mRNA levels subsequent to SEB exposure. The use of this piglet model will continue to elucidate the pathogenesis of SEB intoxication and facilitate the testing of new therapeutic regimens that may better correlate with human lesions.
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Performance of Keyhole Limpet Hemocyanin (KLH) as an Antigen Carrier for Protein Antigens Depends on KLH Property and Conjugation Route. THE JOURNAL OF IMMUNOLOGY 2016. [DOI: 10.4049/jimmunol.196.supp.76.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
KLH naturally exists either as high molecular weight (HMW) cylinders composed of 20 copies of subunits, or as separate subunits (Subunit). The molecular weight of KLH Subunit is about 400kDa. Owing mainly to its large size, and the abundant and complex carbohydrate structures on its peptide chains, KLH has been widely used for decades as an immune stimulant, antigen carrier, and vaccine component. But, how to characterize the properties of KLH as an antigen carrier through functional assays remains to be determined. At Stellar, we conjugated KLH of different formats and sources with ovalbumin (OVA) and fluorescence tag-conjugated OVA through different conjugation routes. Dendritic cells (DCs) derived from mouse bone marrow mononuclear cells and mouse DC line JAWSII were pulsed with these conjugates. By utilizing DC uptake assays and measuring the fluorescence intensity of DC lysate supernatant, the amount of KLH- OVA-fluorescence conjugates uptaken by DCs was quantitatively determined. With flow cytometry, both the DC maturation markers, and the amount of ovalbumin epitopes that are presented by MHC II molecules of DCs, were measured. To further compare the property of KLH-protein conjugates as potential vaccines, we vaccinated mice with OVA. OVA-specific memory T cells extracted from the vaccinated mice were stimulated with DCs that had been pulsed with KLH-OVA conjugates. T cell proliferation and cytokine release from these stimulated T cells were quantitatively measured and compared. To summarize, with the functional assays we designed, we found that the performance of KLH as a carrier for protein antigens depends on KLH property and conjugation route.
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Measuring the properties of different forms of keyhole limpet hemocyan reveals important differences (VAC5P.1116). THE JOURNAL OF IMMUNOLOGY 2015. [DOI: 10.4049/jimmunol.194.supp.73.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
KLH can exist as cylinders composed of 20 copies (didecamer) of subunits, or as separate subunits. It is a well-established immune stimulant and vaccine component. However, literature reports cite dramatically different immune responses to different preparations of KLH. We are developing functional assays to investigate the immunogenicity of different forms and preparations of KLH with the goal of improving the predictive outcome of its use as vaccine carrier or diagnostic agent for both research and clinical studies. Dendritic cells (DCs) derived from mouse bone marrow mononuclear cells, human PBMC, mouse DC line JAWSII, as well as human leukemia lines THP-1 and KG-1, were treated with different forms of KLH. To compare the efficiency of DCs to stimulate KLH-specific adaptive immune responses, KLH treated DCs were used to activate T cells extracted from spleens of mice that were immunized with KLH. DC antigen uptake efficiency, DC maturation, T cell proliferation and cytokine secretion were compared. Ovalbumin was conjugated to different forms of KLH. DCs derived from mouse bone marrow mononuclear cells were treated with the KLH-Ovalbumin conjugates for antigen uptake efficiency and ovalbumin-specific T cell activation studies. We found that didecameric KLH and subunit KLH have significantly different properties. We report here the results of these studies which suggest the need for methods to identify appropriate forms of KLH when used as hapten carrier or immunogen.
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ASSA14-06-02 Correction of Tetralogy of Fallot in 252 Adult Patients. BRITISH HEART JOURNAL 2015. [DOI: 10.1136/heartjnl-2014-307109.74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Monochromatic visible light "photoinitibitor": Janus-faced initiation and inhibition for storage of colored 3D images. J Am Chem Soc 2014; 136:8855-8. [PMID: 24930947 DOI: 10.1021/ja502366r] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Controlling the kinetics and gelation of photopolymerization is a significant challenge in the fabrication of complex three-dimensional (3D) objects as is critical in numerous imaging, lithography, and additive manufacturing techniques. We propose a novel, visible light sensitive "photoinitibitor" which simultaneously generates two distinct radicals, each with their own unique purpose-one radical each for initiation and inhibition. The Janus-faced functions of this photoinitibitor delay gelation and dramatically amplify the gelation time difference between the constructive and destructive interference regions of the exposed holographic pattern. This approach enhances the photopolymerization induced phase separation of liquid crystal/acrylate resins and the formation of fine holographic polymer dispersed liquid crystal (HPDLC) gratings. Moreover, we construct colored 3D holographic images that are visually recognizable to the naked eye under white light.
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Differential characteristics and in vitro angiogenesis of bone marrow- and peripheral blood-derived endothelial progenitor cells: evidence from avian species. Cell Prolif 2014; 47:290-8. [PMID: 24824967 DOI: 10.1111/cpr.12111] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 04/01/2014] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVES This study was conducted to compare phenotypes and in vitro angiogenic capacity of putative endothelial progenitor cells (EPCs) derived from bone marrow (BM) and peripheral blood (PB), from an avian species. MATERIALS AND METHODS Mononuclear cells were isolated from chicken BM and PB (BMMNCs and PBMNCs) and cultured in EGM-2 medium. Cells at days 7-14 were used for the experiments. Expression of progenitor and endothelial markers, number of Dil-ac-LDL/lectin dual-positive cells and adipogenic and osteogenic differentiation were determined. Migration and in vitro angiogenic ability between BMMNC- and PBMNC-derived cells were compared. RESULTS PBMNCs developed typical EPC appearance, with initial spindle shape followed by a cobblestone form, whereas BMMNC-derived cells retained their constitutive spindle-like morphology throughout the study. Cells derived from both sources expressed CD133, CD31 and VEGFR-2, although PBMNCs-derived cells had lower CD133 expression. Nevertheless, number of Dil-ac-LDL/lectin dual-positive cells did not differ between groups. Adipogenic and osteogenic lineages were verified in BMMNC- but not in PBMNC-derived cells. PBMNC-derived cells formed tubular networks on Matrigel. However, BMMNC-derived cells formed few tube-like structures, which were not morphologically comparable to those developed by their counterparts. CONCLUSION Our results suggest that so called EPCs derived from BMMNCs are not 'true' EPCs, supporting previous findings on mammals that BM may not serve as an optimal isolation source of EPCs.
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Concurrent Solution-Like Decoloration Rate and High Mechanical Strength from Polymer-Dispersed Photochromic Organogel. Macromol Rapid Commun 2014; 35:741-6. [DOI: 10.1002/marc.201300891] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 12/24/2013] [Indexed: 11/09/2022]
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Highly diffractive, reversibly fast responsive gratings formulated through holography. RSC Adv 2014. [DOI: 10.1039/c3ra45570j] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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Glycosylation Status and Presentation Format Determines Immune Responses Induced by Keyhole Limpet Hemocyanin (KLH) (52.16). THE JOURNAL OF IMMUNOLOGY 2012. [DOI: 10.4049/jimmunol.188.supp.52.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
KLH is a heavily glycosylated protein. It can exist as 8MDa cylinders composed of 20 copies (didecamer) of a 400KDa subunit, or as separate subunits. KLH is a well-established immune stimulant, hapten carrier and generalized vaccine component. It is also used as a therapeutic vaccine against bladder cancer. Besides its application in schistosomiasis diagnosis, chronic stress such as post-traumatic stress disorder (PTSD) recently has been found to suppress KLH-induced adaptive immune responses, suggesting the potential for KLH in PTSD diagnosis. However, literature reports cite dramatically different immune responses to different preparations of the molecule, thus limiting the predictive outcome of using KLH as antigen carrier, vaccine adjuvant, vaccine or diagnostic agent. Mechanisms responsible for this variation remain largely unknown. Using lectin array and dendritic cell (DC) maturation assay, we found that KLH didecamers and subunits from different sources exhibit different carbohydrate profiles, and that the potency of KLH-induction of DC maturation varied with glycosylation status. We also found that conjugating KLH to poly (ethylene glycol)-based dendrimers significantly boosted DC maturation. Using endocytosis inhibitors, glycosylation status and presentation format was found to determine KLH uptake pathways in DCs. We thus propose that KLH can be tailored by manipulating glycosylation status and presentation format for optimal activity to meet different needs.
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blaKPC and rmtB on a single plasmid in Enterobacter amnigenus and Klebsiella pneumoniae isolates from the same patient. Eur J Clin Microbiol Infect Dis 2012; 31:1585-91. [PMID: 22237458 PMCID: PMC3364413 DOI: 10.1007/s10096-011-1481-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2011] [Accepted: 10/28/2011] [Indexed: 11/13/2022]
Abstract
Enterobacter amnigenus (EA76) and Klebsiella pneumoniae (KP76) isolates with multidrug-resistant (MDR) patterns were identified from the same patient in the neurosurgery department of our hospital. An outbreak of MDR K. pneumoniae had also occurred in this department. To characterize the resistance mechanism and molecular epidemiology of these isolates, sequential experiments including antimicrobial susceptibility testing, polymerase chain reaction (PCR), plasmid analysis, pulsed field gel electrophoresis (PFGE), and multilocus sequence typing (MLST) were performed. EA76 and KP76 were resistant to all of the antibiotics tested, except colistin and tigecycline. blaKPC-2, blaTEM-1, blaSHV-12, blaCTX-M-3, blaCTX-M-14, and rmtB genes were identified in both isolates, with blaKPC-2, blaTEM-1, blaCTX-M-14, and rmtB being co-carried on one plasmid in each isolate. Further analysis showed different restriction patterns between the two KPC-carrying plasmids. Of the 11 carbapenem-resistant isolates found in the outbreak, all were resistant to all of the β-lactams tested, with 63.64% (7/11) also exhibiting resistance to aminoglycosides and 72.73% (8/11) exhibiting resistance to quinolones. PCR analysis and molecular typing of the 11 K. pneumoniae strains revealed that the seven aminoglycoside-resistant isolates shared the same antibiotic-resistant gene pattern and identical or one-band-difference PFGE profiles relative to KP76. In addition, all of the eight aminoglycoside-resistant isolates, including KP76, belonged to the national epidemic clone ST11. The overall results indicate the emergence of E. amnigenus and outbreak of ST11 K. pneumoniae, with both co-harboring blaKPC and rmtB genes on a single plasmid in our neurosurgery wards.
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Abstract
Aims The pathogenesis of obesity remains incompletely understood and the exploration of the role of novel proteins in obesity may provide important insights into its causes and treatments. Here we report a previously unidentified role for synphilin-1 in the controls of food intake and body weight. Synphilin-1, a cytoplasmic protein, was initially identified as an interaction partner of alpha-synuclein, and has implications in Parkinson's disease pathogenesis related to protein aggregation. Subjects and methods To study the in vivo role of synphilin-1, we characterized a human synphilin-1 transgenic mouse (SP1) by assessing synphilin-1 expression, plasma parameters, food intake and spontaneous activity to determine the major behavioral changes and their consequences in the development of the obesity phenotype. Results Expression of human synphilin-1 in brain neurons in SP1 mice resulted in increased food intake, body weight and body fat. SP1 mice also displayed hyperinsulinemia, hyperleptinemia and impaired glucose tolerance. Pair-feeding SP1 mice to amounts consumed by non-transgenic mice prevented the increased body weight, adiposity, hyperinsulinemia and hyperleptinemia demonstrating that these were all the consequences of increased food intake. Transgenic expression of synphilin-1 was enriched in hypothalamic nuclei involved in feeding control, and fasting induced elevated endogenous synphilin-1 levels at these sites, suggesting that synphilin-1 is an important player in the hypothalamic energy balance regulatory system. Conclusion These studies identify a novel function of synphilin-1 in controlling food intake and body weight, and may provide a unique obesity model for future studies of obesity pathogenesis and therapeutics.
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Viral-mediated overexpression of NPY in the dorsomedial hypothalamus causes hyperphagia and obesity in Sprague Dawley rats. Appetite 2011. [DOI: 10.1016/j.appet.2011.05.124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Galectin-9 binding to cell surface protein disulfide isomerase regulates the redox environment to enhance T-cell migration and HIV entry. Proc Natl Acad Sci U S A 2011; 108:10650-5. [PMID: 21670307 PMCID: PMC3127870 DOI: 10.1073/pnas.1017954108] [Citation(s) in RCA: 173] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Interaction of cell surface glycoproteins with endogenous lectins on the cell surface regulates formation and maintenance of plasma membrane domains, clusters signaling complexes, and controls the residency time of glycoproteins on the plasma membrane. Galectin-9 is a soluble, secreted lectin that binds to glycoprotein receptors to form galectin-glycoprotein lattices on the cell surface. Whereas galectin-9 binding to specific glycoprotein receptors induces death of CD4 Th1 cells, CD4 Th2 cells are resistant to galectin-9 death due to alternative glycosylation. On Th2 cells, galectin-9 binds cell surface protein disulfide isomerase (PDI), increasing retention of PDI on the cell surface and altering the redox status at the plasma membrane. Cell surface PDI regulates integrin function on platelets and also enhances susceptibility of T cells to infection with HIV. We find that galectin-9 binding to PDI on Th2 cells results in increased cell migration through extracellular matrix via β3 integrins, identifying a unique mechanism to regulate T-cell migration. In addition, galectin-9 binding to PDI on T cells potentiates infection with HIV. We identify a mechanism for regulating cell surface redox status via a galectin-glycoprotein lattice, to regulate distinct T-cell functions.
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Galectin multimerization and lattice formation are regulated by linker region structure. Glycobiology 2011. [DOI: 10.1093/glycob/cwr011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract
β-Galactoside-binding lectin 9 (galectin-9) is a tandem repeat-type member of the galectin family. It was initially characterized as an eosinophil chemoattractant and an inducer of apoptosis in thymocytes. Subsequently, galectin-9 was identified as a ligand for transmembrane immunoglobulin mucin domain 3 (Tim-3), a type I glycoprotein induced on T cells during chronic inflammation. Work in autoimmune diseases and chronic viral infections have led to the current hypothesis that the function of Tim-3 is to limit immune responses. However, it is still not known to what degree these effects are due to the galectin-9/Tim-3 interaction. In this study, we show that galectin-9 is not limited to the role of a pro-apoptotic agent, but that it can also induce the production of pro-inflammatory cytokines from T helper cells. This effect is dose-dependent and does not require Tim-3. These findings suggest that the effects of galectin-9 on T cells are more complex than previously thought and are mediated by additional receptors apart from Tim-3.
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Galectin multimerization and lattice formation are regulated by linker region structure. Glycobiology 2010; 21:6-12. [PMID: 20864568 DOI: 10.1093/glycob/cwq144] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Galectins regulate cellular functions by binding to glycan ligands on cell surface glycoprotein receptors. Prototype galectins, such as galectin-1, are one carbohydrate recognition domain (CRD) monomers that noncovalently dimerize, whereas tandem-repeat galectins, such as galectin-9, have two non-identical CRDs connected by a linker domain. Dimerization of prototype galectins, or both CRDs in tandem-repeat galectins, is typically required for the crosslinking of glycoprotein receptors and subsequent cellular signaling. Several studies have found that tandem-repeat galectins are more potent than prototype galectins in triggering many cell responses, including cell death. These differences could be due to CRD specificity, the presence or absence of a linker domain between CRDs, or both. To interrogate the basis for the increased potency of tandem-repeat galectins compared with prototype galectins in triggering cell death, we created three tandem-repeat galectin constructs with different linker regions joining identical galectin-1 CRDs, so that any differences we observed would be due to the contribution of the linker region rather than due to CRD specificity. We found that random-coil or rigid α-helical linkers that permit separation of the two galectin-1 CRDs facilitated the formation of higher-order galectin multimers and that these galectins were more potent in binding to glycan ligands and cell surface glycoprotein receptors, as well as triggering T cell death, compared with native galectin-1 or a construct with a short rigid linker. Thus, the increased potency of tandem-repeat galectins compared with prototype galectins is likely due to the ability of the linker domain to permit intermolecular CRD interactions, resulting in the formation of higher-order multimers with increased valency, rather than differences in CRD specificity.
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Knockdown of NPY expression in the dorsomedial hypothalamus ameliorates high-fat diet-induced obesity in rats. Appetite 2010. [DOI: 10.1016/j.appet.2010.04.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Sialic acids in T cell development and function. Biochim Biophys Acta Gen Subj 2009; 1790:1599-610. [DOI: 10.1016/j.bbagen.2009.07.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 11/16/2022]
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Abstract
Galectin-1, a beta-galactoside-binding protein highly expressed in the thymus, induces apoptosis of specific thymocyte subsets and activated T cells. Galectin-1 binds to N- and O-glycans on several glycoprotein receptors, including CD7, CD43, and CD45. Here we show that galectin-1 signaling through CD45, which carries both N- and O-glycans, is regulated by CD45 isoform expression, core 2 O-glycan formation and the balance of N-glycan sialylation. Regulation of galectin-1 T cell death by O-glycans is mediated through CD45 phosphatase activity. While galectin-1 signaling in cells expressing low molecular weight isoforms of CD45 requires expression of core 2 O-glycans (high affinity ligands for galectin-1), galectin-1 signaling in cells expressing a high molecular weight isoform of CD45 does not require core 2 O-glycans, suggesting that a larger amount of core 1 O-glycans (low affinity ligands for galectin-1) is sufficient to overcome lack of core 2 O-glycans. Furthermore, regulation of galectin-1 signaling by alpha2,6-sialylation of N-glycans is not solely dependent on CD45 phosphatase activity and can be modulated by the relative expression of enzymes that attach sialic acid in an alpha2,6- or alpha2,3-linkage. Thus, N- and O-glycans modulate galectin-1 T cell death by distinct mechanisms, and different glycosylation events can render thymocytes susceptible or resistant to galectin-1.
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The cellular and molecular immune response of the weanling piglet to staphylococcal enterotoxin B. Exp Biol Med (Maywood) 2009; 234:1305-15. [PMID: 19855072 DOI: 10.3181/0901-rm-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Staphylococcal enterotoxin B (SEB) is a biothreat agent, etiologic agent of food poisoning, and potent inducer of toxic shock syndrome. This heat-stable exoprotein is thought to act as a superantigen to induce T cell-specific pathology. Most animal models do not accurately map the clinical syndrome of human SEB exposure. Previously, we have demonstrated the utility of the weanling piglet model of SEB intoxication. Here, we analyze gross and histopathologic specimens from lymphoid tissue of these animals. Hematological testing was completed to observe changes in circulating leukocytes. Further, these leukocytes were differentiated and the subsets were subsequently analyzed using flow cytometry. Cytokine mRNA was quantified in lymphoid tissue and peripheral blood cells and compared to actual protein concentration using ELISA. The mRNA expression levels for several cell markers implicated in T and B cell differentiation were quantified and compared to control animals, as were levels for apoptosis-related genes. Lymphadenopathy was constantly seen post mortem. SEB-exposed animals had a leukocytosis which increased linearly over the time course. Monocyte levels increased over time, while lymphocyte levels peaked at 6h and then returned to baseline. Most cytokines had mRNA levels that were upregulated after exposure. Detection of serum cytokine changes was accomplished; however, these patterns did not always follow those seen in the differentially expressed genes. Both pro- and anti-apoptotic genes were differentially expressed in exposed animals. This paper reports, for the first time, the immunological findings in the weanling piglet model of SEB intoxication. From this work it is clear that there is not one absolute cell-mediated pathway contributing to the pathology these animals exhibit as a result of SEB exposure.
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High-fat diet offsets the long-lasting effects of a four-week running wheel access on food intake and body weight in OLETF rats. Appetite 2009. [DOI: 10.1016/j.appet.2009.04.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Dorsomedial hypothalamic neuropeptide Y modulates the satiety actions of peripheral cholecyctokinin. Appetite 2008. [DOI: 10.1016/j.appet.2008.04.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Synphilin-1 induces hyperphagia-mediated obesity in mice. Appetite 2008. [DOI: 10.1016/j.appet.2008.04.149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Characterization of the feeding inhibition and neural activation produced by dorsomedial hypothalamic cholecystokinin administration. Neuroscience 2008; 152:178-88. [PMID: 18248910 DOI: 10.1016/j.neuroscience.2007.12.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Revised: 09/25/2007] [Accepted: 12/03/2007] [Indexed: 12/18/2022]
Abstract
Within the dorsomedial hypothalamus (DMH), cholecystokinin (CCK) has been proposed to modulate neuropeptide Y (NPY) signaling to affect food intake. However, the neural circuitry underlying the actions of this CCK-NPY signaling system in the controls of food intake has yet to be determined. We sought to characterize the feeding inhibition and brain neural activation produced by CCK administration into the DMH of rats. We determined the time course of feeding inhibitory effects of exogenous DMH CCK, assessed NPY gene expression in the DMH in response to DMH CCK administration, and characterized c-Fos activation in the entire brain induced by CCK injection into the DMH using c-Fos like immunohistochemistry. We found that parenchymal injection of CCK into the DMH decreased food intake during the entire 22 h observation period, with a primary effect in the first 4 h, and down-regulated NPY gene expression in the DMH. c-Fos immunohistochemistry revealed that DMH CCK increased the number of c-Fos positive cells in the paraventricular nucleus (PVN), arcuate nucleus, suprachiasmatic nucleus and retrochiasmatic area as well as in the contralateral DMH. This pattern of activity is different from that produced by peripherally administered CCK which is short acting and primarily activates neurons in the nucleus of the solitary tract and area postrema, as well as the PVN and DMH. Together, these data suggest that DMH CCK plays an important role in the control of food intake, and does so by activating different pathways from those activated by peripheral CCK.
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Integration of physiopathogenomics to identify progression of illness & stage‐appropriate therapeutic targets in a model of staphylococcal enterotoxininduced lethal shock. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.1019.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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CD45 Phosphatase Domain Required For Regulation Of Galectin‐1 Induced T cell Death. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.648.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Structural Features of Galectin‐9 and Galectin‐1 that Determine Distinct T cell Death Pathways. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.808.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Possible role of hydrogen sulfide on the preservation of donor rat hearts. Transplant Proc 2008; 39:3024-9. [PMID: 18089314 DOI: 10.1016/j.transproceed.2007.05.086] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2007] [Accepted: 05/23/2007] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The aim of this study was to observe the preservative effect of hydrogen sulfide (H2S) on donor rat hearts. MATERIALS AND METHODS The hearts of 24 Sprague-Dawley rats were perfused on a Langendorff perfusion column for 30 minutes. We calculated and recorded the left ventricular-developed pressure (LVDP), and positive and negative derivatives of left ventricular systolic pressure (LVSP; +dP/dt and -dP/dt). Hearts were then arrested and stored for 6 hours at 4 degrees C: group 1, Krebs-Henseleit (KH) solution; group 2, KH solution with 1 micromol/L NaHS; group 3, KH solution with 1 micromol/L NaHS and 10 micromol/L glibenclamide; group 4, St. Thomas II solution. Hearts were transferred back to the Langendorff column. After stabilizing for 30 minutes, LV performance was assessed as before. The donor hearts were kept for pathological study including myocardial water ratio, ATP content, and myocyte apoptosis index. RESULTS The recovery rates of +dp/dtmax, -dp/dtmax, and LVDP of groups 2 and 4 were much better than those of groups 1 and 3. The hearts contracted immediately after reperfusion in group 4. Ventricular fibrillation was seen before contraction in the other 3 groups, with the longest duration in group. No significant difference in myocardial water ratio was found. The ATP content was the highest in group 2. Apoptosis was observed in the 4 groups with the lowest apoptosis index in group 2. CONCLUSIONS H2S has a protective effect on rat donor hearts at the concentration of 1 micromol/L. The protective effect is better than that of St. Thomas II solution. The protective effect of H2S can be blocked by glibenclamide.
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Structural features of galectin-9 and galectin-1 that determine distinct T cell death pathways. J Biol Chem 2008; 283:12248-58. [PMID: 18258591 DOI: 10.1074/jbc.m800523200] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The galectin family of lectins regulates multiple biologic functions, such as development, inflammation, immunity, and cancer. One common function of several galectins is the ability to trigger T cell death. However, differences among the death pathways triggered by various galectins with regard to glycoprotein receptors, intracellular death pathways, and target cell specificity are not well understood. Specifically, galectin-9 and galectin-1 both kill thymocytes, peripheral T cells, and T cell lines; however, we have found that galectin-9 and galectin-1 require different glycan ligands and glycoprotein receptors to trigger T cell death. The two galectins also utilize different intracellular death pathways, as galectin-9, but not galectin-1, T cell death was blocked by intracellular Bcl-2, whereas galectin-1, but not galectin-9, T cell death was blocked by intracellular galectin-3. Target cell susceptibility also differed between the two galectins, as galectin-9 and galectin-1 killed different subsets of murine thymocytes. To define structural features responsible for distinct activities of the tandem repeat galectin-9 and dimeric galectin-1, we created a series of bivalent constructs with galectin-9 and galectin-1 carbohydrate recognition domains connected by different peptide linkers. We found that the N-terminal carbohydrate recognition domain and linker peptide contributed to the potency of these constructs. However, we found that the C-terminal carbohydrate recognition domain was the primary determinant of receptor recognition, death pathway signaling, and target cell susceptibility. Thus, carbohydrate recognition domain specificity, presentation, and valency make distinct contributions to the specific effects of different galectins in initiating T cell death.
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Neuropeptide Y Y1 and Y5 receptors are co-expressed with GRP mRNA in the rat hypothalamic paraventricular nucleus. Appetite 2007. [DOI: 10.1016/j.appet.2007.03.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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