Mitochondrial apoptosis inducing factor (AIF) is a redox-active enzyme that participates to the biogenesis/maintenance of complex I of the respiratory chain, yet also contributes to catabolic ...reactions in the context of regulated cell death when AIF translocates to the cytosol and to the nucleus. Here we explore the contribution of AIF to cell death induced by menadione (2-methyl-1,4-naphtoquinone; also called vitamin K3) in conditions in which this pro-oxidant does not cause the mitochondrial release of AIF, yet causes caspase-independent cell killing. Depletion of AIF from human cancer cells reduced the cytotoxicity of menadione. This cytoprotective effect was accompanied by the maintenance of high levels of reduced glutathione (GSH), which are normally depleted by menadione. In addition, AIF depletion reduced the arylation of cellular proteins induced by menadione. This menadione-triggered arylation, which can be measured by a fluorescence assay, is completely suppressed by addition of exogenous glutathione or N-acetyl cysteine. Complex I inhibition by Rotenone did not mimic the cytoprotective action of AIF depletion. Altogether, these results are compatible with the hypothesis that mitochondrion-sessile AIF facilitates lethal redox cycling of menadione, thereby precipitating protein arylation and glutathione depletion.
The development of the industry has increased the demand for energy storage, making the provision of energy storage devices essential. The supercapacitor is one of the potential energy storage ...devices, and carbon aerogel (CA) is a promising candidate for supercapacitor electrode fabrication. Ni-doped nipa palm shell-derived CA (Ni-NS-CA) was used to fabricate the electrode for supercapacitors to save production costs and utilize biomass wastes. Ni-NS-CA was synthesized via a three-step process: Hydrogel making through cross-linking (SA, Ni
2+
), freeze-drying, and pyrolysis. The characteristics of Ni-NS-CA are analyzed using a scanning electron microscope, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy, and Nitrogen adsorption–desorption isotherm 77 K. The electrochemical properties of Ni-NS-CA was analyzed via cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. With stable energy storage results (104.15 F g
−1
) and the electrochemical system based on Ni-NS-CA extends its application to Hg
2+
sensing. Moreover, Ni-NS-CA was a potential material to solve oil spills, which has an oil adsorption capacity of 31.24 g g
−1
.
Graphical abstract
Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein that, beyond its apoptotic function, is required for the normal expression of major respiratory chain complexes. Here we identified an ...AIF-interacting protein, CHCHD4, which is the central component of a redox-sensitive mitochondrial intermembrane space import machinery. Depletion or hypomorphic mutation of AIF caused a downregulation of CHCHD4 protein by diminishing its mitochondrial import. CHCHD4 depletion sufficed to induce a respiratory defect that mimicked that observed in AIF-deficient cells. CHCHD4 levels could be restored in AIF-deficient cells by enforcing its AIF-independent mitochondrial localization. This modified CHCHD4 protein reestablished respiratory function in AIF-deficient cells and enabled AIF-deficient embryoid bodies to undergo cavitation, a process of programmed cell death required for embryonic morphogenesis. These findings explain how AIF contributes to the biogenesis of respiratory chain complexes, and they establish an unexpected link between the vital function of AIF and the propensity of cells to undergo apoptosis.
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•AIF interacts with CHCHD4, a regulator of the intermembrane space import machinery•AIF regulates specific respiratory chain complexes by acting upstream of CHCHD4•AIF is indispensable for translation-coupled mitochondrial import of CHCHD4•Restoring CHCHD4 reverses the metabolic and cell death phenotypes of Aif−/y ESCs
Hangen et al. show that the mitochondrial protein AIF regulates the biogenesis of respiratory chain complexes by interacting with, and by controlling the mitochondrial import of the mammalian homolog of yeast MIA40, CHCHD4, which is the central component of a redox-sensitive mitochondrial intermembrane space import machinery.
•Plastic bags were used as raw materials for the synthesis of aerogel.•GO/PBA is hydrophobically modified with PBMS to increase selectivity in oil/water.•The ability to absorb moisture up to 17 g/g ...compared to PBA of only 10 g/g.
Plastic bags, also known as nylon bags, plastic packaging, latex bags, and bubble bags, are one of the most harmful segments of plastic waste to the ecosystem. Researchers estimate that plastic bags in natural surroundings take between 500 and 1000 years to fully decompose. Therefore, the recycling of non-biodegradable plastic products such as plastic bags is always a prime topic. In this study, plastic bags were used as raw materials for the synthesis of aerogel (PBA) and modified with graphene oxide (GO/PBA) to increase mechanical strength. Young's module results show that GO/PBA can withstand a maximum compression of about 55 N while PBA has a compressive force of only about 10 N. GO/PBA has a porous 3D structure, low density (0.026 g/cm3), and the major elements are C, O with the existence of C − O, which are suitable as hygroscopic materials. GO/PBA are able to absorb moisture up to 17 g/g compared to that of PBA with 10 g/g. Besides, GO/PBA is hydrophobically modified with PDMS (PDMS/GO/PBA) to increase selectivity in oil/water systems, oil spill treatment application with high oil adsorption capacity reaching 27 g/g, about 10 times the mass of the material. Thus, GO/PBA and PBMS/GO/PBA were successfully synthesized for the application of desiccant and oil adsorbent, respectively. The kinetics of the two adsorption processes are shown by pseudo-order first and second models.
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At this time, multi-application materials are developing to match the trend of green sustainable energy development. And with characteristics acting as high porosity, light weight, bulk form with ...diverse pores, and high chemical compatibility, metal-doped carbon aerogel becomes a potential material. In this study, Fe-doped carbon aerogel with crosslinking sodium alginate (Fe-SA-CA) was synthesized through a simple process of freeze-drying, aerogel pyrolysis, and pyrolysis temperatures (600–800 °C) were investigated to find suitable materials for adsorption and electrochemical applications. The characteristics of the material are analyzed by modern methods, proving that the surface of the material has a variety of pores with a size approximately 2 nm, and has the main components including C, O, and Fe. Fe-SA-CA shows potential for adsorption of oils, organic solvents, and crystal violet pigments. In particular, electrochemical properties of Fe-SA-CA are determined through cyclic voltammetry, galvanostatic charge discharge, and electrochemical impedence spectroscopy, to obtain high specific capacitance (203 F/g at 50 mV/s), constant discharge capacity over 500 cycles. Futhermore, thanks to the presence of the element Fe, the magnetic material is easily recovered with a magnet after used. In addition, the precursor used in the study is cellulose from nipa coconut shells - a large amount of biomass waste in Vietnam, thereby reducing production costs, limiting chemicals, and expanding the potential application of the Fe-doped carbon aerogel.
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In Vietnam, scientific research is no longer just the work of scientists, graduate students, scholars, or lecturers; tertiary students are also encouraged to conduct scientific research. Therefore, ...the scientific research work of students receives more attention from educators. The research on carrying out scientific research of students is also therefore increasing. However, researchers do not seem to have paid enough attention to the role of supervisors during the supervision process. The evidence is that there are few studies on supervisors in Vietnam. Therefore, this study was conducted to learn about the role of supervisors from the student's perspective and expectations. Specifically, this study was conducted quantitatively with the use of a questionnaire consisting of 49 questions with a 5-point Likert scale. A total of 100 English-major students at a university in Southwest Vietnam participated in this study by answering the questionnaire. The results from the questionnaire show that students had high expectations from their supervisors. Specifically, students expect their supervisor to be someone who respects their opinions, has good scientific research knowledge, can give constructive comments, and is always willing to help them when needed. Based on research findings, supervisors are encouraged to participate in professional development training related to scientific research to improve their research knowledge and skills. Along with that, supervisors need to be aware of their role during the process of guiding students to do scientific research. Article visualizations:
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