Few Layer Graphene Does Not Affect Cellular Homeostasis of Mouse Macrophages

Graphene-related materials (GRMs) are widely used in various applications due to their unique properties. A growing number of reports describe the impact of different carbon nanomaterials, including graphene oxide (GO), reduced GO (rGO), and carbon nanotubes (CNT), on immune cells, but there is still a very limited number of studies on graphene. In this work, we investigated the biological responses of few layer graphene (FLG) on mouse macrophages (bone marrow derived macrophages, BMDMs), which are part of the first line of defense in innate immunity. In particular, our paper describes our findings of short-term FLG treatment in BMDMs with a focus on observing material internalization and changes in general cell morphology. Subsequent investigation of cytotoxicity parameters showed that increasing doses of FLG did not hamper the viability of cells and did not trigger inflammatory responses. Basal level induced autophagic activity sufficed to maintain the cellular homeostasis of FLG treated cells. Our results shed light on the impact of FLG on primary macrophages and show that FLG does not elicit immunological responses leading to cell death.

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Nanostructuring few-layer graphene films with swift heavy ions for electronic application: tuning of electronic and transport properties

Nanoscale ◽

10.1039/c8nr03062f ◽

2018 ◽

Vol 10 (30) ◽

pp. 14499-14509 ◽

Cited By ~ 14

Author(s):

N. A. Nebogatikova ◽

I. V. Antonova ◽

S. V. Erohin ◽

D. G. Kvashnin ◽

A. Olejniczak ◽

...

Keyword(s):

Heavy Ions ◽

High Energy ◽

Electronic Application ◽

Layer Graphene ◽

Swift Heavy Ions ◽

Graphene Films ◽

High Energy Ions ◽

Application Tuning ◽

Few Layer Graphene ◽

The Impact

The morphology and electronic properties of single and few-layer graphene films nanostructured by the impact of heavy high-energy ions have been studied.

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Modern methods of obtaining few-layer graphene structures by the method of electrochemical exfoliation of graphite

Perspektivnye Materialy ◽

10.30791/1028-978x-2018-7-5-15 ◽

2018 ◽

pp. 5-15

Author(s):

E. S. Bakunin ◽

◽

E. Yu. Obraztsova ◽

A. V. Rukhov ◽

◽

...

Keyword(s):

Electrochemical Exfoliation ◽

Layer Graphene ◽

Modern Methods ◽

Few Layer Graphene ◽

Graphene Structures

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AMPK activates Parkin independent autophagy and improves post sepsis immune defense against secondary bacterial lung infections

Scientific Reports ◽

10.1038/s41598-021-90573-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nathaniel B. Bone ◽

Eugene J. Becker ◽

Maroof Husain ◽

Shaoning Jiang ◽

Anna A. Zmijewska ◽

...

Keyword(s):

Bacterial Infections ◽

Pathogenic Bacteria ◽

Inflammatory Responses ◽

Abdominal Sepsis ◽

Immune Defense ◽

Bacterial Killing ◽

Lung Infections ◽

Sepsis Survivors ◽

The Impact

AbstractMetabolic and bioenergetic plasticity of immune cells is essential for optimal responses to bacterial infections. AMPK and Parkin ubiquitin ligase are known to regulate mitochondrial quality control mitophagy that prevents unwanted inflammatory responses. However, it is not known if this evolutionarily conserved mechanism has been coopted by the host immune defense to eradicate bacterial pathogens and influence post-sepsis immunosuppression. Parkin, AMPK levels, and the effects of AMPK activators were investigated in human leukocytes from sepsis survivors as well as wild type and Park2−/− murine macrophages. In vivo, the impact of AMPK and Parkin was determined in mice subjected to polymicrobial intra-abdominal sepsis and secondary lung bacterial infections. Mice were treated with metformin during established immunosuppression. We showed that bacteria and mitochondria share mechanisms of autophagic killing/clearance triggered by sentinel events that involve depolarization of mitochondria and recruitment of Parkin in macrophages. Parkin-deficient mice/macrophages fail to form phagolysosomes and kill bacteria. This impairment of host defense is seen in the context of sepsis-induced immunosuppression with decreased levels of Parkin. AMPK activators, including metformin, stimulate Parkin-independent autophagy and bacterial killing in leukocytes from post-shock patients and in lungs of sepsis-immunosuppressed mice. Our results support a dual role of Parkin and AMPK in the clearance of dysfunctional mitochondria and killing of pathogenic bacteria, and explain the immunosuppressive phenotype associated Parkin and AMPK deficiency. AMPK activation appeared to be a crucial therapeutic target for the macrophage immunosuppressive phenotype and to reduce severity of secondary bacterial lung infections and respiratory failure.

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Omnidirectional terahertz photonic band gap broaden effect in one-dimensional photonic crystal containing few-layer graphene

Optics Communications ◽

10.1016/j.optcom.2021.126898 ◽

2021 ◽

Vol 490 ◽

pp. 126898

Author(s):

Feng Wu ◽

Mingyuan Chen ◽

Zhanxu Chen ◽

Chengping Yin

Keyword(s):

Photonic Crystal ◽

Band Gap ◽

Photonic Band Gap ◽

One Dimensional ◽

Dimensional Photonic Crystal ◽

Layer Graphene ◽

Few Layer Graphene ◽

Photonic Band

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Properties of Silicone Rubber-Based Composites Reinforced with Few-Layer Graphene and Iron Oxide or Titanium Dioxide

Polymers ◽

10.3390/polym13101550 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1550

Author(s):

Vineet Kumar ◽

Anuj Kumar ◽

Minseok Song ◽

Dong-Joo Lee ◽

Sung-Soo Han ◽

...

Keyword(s):

Magnetic Properties ◽

Titanium Dioxide ◽

Iron Oxide ◽

Stress Relaxation ◽

Silicone Rubber ◽

Room Temperature ◽

Relaxation Rates ◽

Layer Graphene ◽

Few Layer Graphene ◽

Mechanical Actuation

The increasing demand for polymer composites with novel or improved properties requires novel fillers. To meet the challenges posed, nanofillers such as graphene, carbon nanotubes, and titanium dioxide (TiO2) have been used. In the present work, few-layer graphene (FLG) and iron oxide (Fe3O4) or TiO2 were used as fillers in a room-temperature-vulcanized (RTV) silicone rubber (SR) matrix. Composites were prepared by mixing RTV-SR with nanofillers and then kept for vulcanization at room temperature for 24 h. The RTV-SR composites obtained were characterized with respect to their mechanical, actuation, and magnetic properties. Fourier-transform infrared spectroscopy (FTIR) analysis was performed to investigate the composite raw materials and finished composites, and X-ray photoelectron spectroscopy (XPS) analysis was used to study composite surface elemental compositions. Results showed that mechanical properties were improved by adding fillers, and actuation displacements were dependent on the type of nanofiller used and the applied voltage. Magnetic stress-relaxation also increased with filler amount and stress-relaxation rates decreased when a magnetic field was applied parallel to the deformation axes. Thus, this study showed that the inclusion of iron oxide (Fe3O4) or TiO2 fillers in RTV-SR improves mechanical, actuation, and magnetic properties.

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Temperature Dependence of G and D’ Phonons in Monolayer to Few-Layer Graphene with Vacancies

Nanoscale Research Letters ◽

10.1186/s11671-020-03414-w ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Mingming Yang ◽

Longlong Wang ◽

Xiaofen Qiao ◽

Yi Liu ◽

Yufan Liu ◽

...

Keyword(s):

Negative Temperature Coefficient ◽

Negative Temperature ◽

Intrinsic Properties ◽

Temperature Dependent ◽

Phonon Interaction ◽

Electron Phonon Interaction ◽

Layer Graphene ◽

A Value ◽

Few Layer Graphene

Abstract The defects into the hexagonal network of a sp2-hybridized carbon atom have been demonstrated to have a significant influence on intrinsic properties of graphene systems. In this paper, we presented a study of temperature-dependent Raman spectra of G peak and D’ band at low temperatures from 78 to 318 K in defective monolayer to few-layer graphene induced by ion C+ bombardment under the determination of vacancy uniformity. Defects lead to the increase of the negative temperature coefficient of G peak, with a value almost identical to that of D’ band. However, the variation of frequency and linewidth of G peak with layer number is contrary to D’ band. It derives from the related electron-phonon interaction in G and D’ phonon in the disorder-induced Raman scattering process. Our results are helpful to understand the mechanism of temperature-dependent phonons in graphene-based materials and provide valuable information on thermal properties of defects for the application of graphene-based devices.

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Few-layer graphene prepared via microwave irradiation of black sesame for supercapacitor applications

Chemical Engineering Journal ◽

10.1016/j.cej.2021.130664 ◽

2021 ◽

Vol 425 ◽

pp. 130664

Author(s):

Xinghe Xu ◽

Shichang Sun ◽

Juan Luo ◽

Rui Ma ◽

Junhao Lin ◽

...

Keyword(s):

Microwave Irradiation ◽

Layer Graphene ◽

Few Layer Graphene ◽

Supercapacitor Applications

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Parenteral Fish-Oil Containing Lipid Emulsions Limit Initial Lipopolysaccharide-Induced Host Immune Responses in Preterm Pigs

Nutrients ◽

10.3390/nu13010205 ◽

2021 ◽

Vol 13 (1) ◽

pp. 205

Author(s):

William Yakah ◽

David Ramiro-Cortijo ◽

Pratibha Singh ◽

Joanne Brown ◽

Barbara Stoll ◽

...

Keyword(s):

Fatty Acid ◽

Fish Oil ◽

Soybean Oil ◽

Inflammatory Responses ◽

Postnatal Period ◽

Lipid Emulsions ◽

Omega 3 ◽

Oil Emulsion ◽

Mixed Oil ◽

The Impact

Multicomponent lipid emulsions are available for critical care of preterm infants. We sought to determine the impact of different lipid emulsions on early priming of the host and its response to an acute stimulus. Pigs delivered 7d preterm (n = 59) were randomized to receive different lipid emulsions for 11 days: 100% soybean oil (SO), mixed oil emulsion (SO, medium chain olive oil and fish oil) including 15% fish oil (MO15), or 100% fish oil (FO100). On day 11, pigs received an 8-h continuous intravenous infusion of either lipopolysaccharide (LPS—lyophilized Escherichia coli) or saline. Plasma was collected for fatty acid, oxylipin, metabolomic, and cytokine analyses. At day 11, plasma omega-3 fatty acid levels in the FO100 groups showed the highest increase in eicosapentaenoic acid, EPA (0.1 ± 0.0 to 9.7 ± 1.9, p < 0.001), docosahexaenoic acid, DHA (day 0 = 2.5 ± 0.7 to 13.6 ± 2.9, p < 0.001), EPA and DHA-derived oxylipins, and sphingomyelin metabolites. In the SO group, levels of cytokine IL1β increased at the first hour of LPS infusion (296.6 ± 308 pg/mL) but was undetectable in MO15, FO100, or in the animals receiving saline instead of LPS. Pigs in the SO group showed a significant increase in arachidonic acid (AA)-derived prostaglandins and thromboxanes in the first hour (p < 0.05). No significant changes in oxylipins were observed with either fish-oil containing group during LPS infusion. Host priming with soybean oil in the early postnatal period preserves a higher AA:DHA ratio and the ability to acutely respond to an external stimulus. In contrast, fish-oil containing lipid emulsions increase DHA, exacerbate a deficit in AA, and limit the initial LPS-induced inflammatory responses in preterm pigs.

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