Dalian University of Technology

About: Dalian University of Technology is a education organization based out in Dalian, China. It is known for research contribution in the topics: Catalysis & Finite element method. The organization has 60890 authors who have published 71921 publications receiving 1188356 citations. The organization is also known as: Dàlián Lǐgōng Dàxué.

Melatonin prevents Drp1-mediated mitochondrial fission in diabetic hearts through SIRT1-PGC1α pathway

Abstract: Myocardial contractile dysfunction is associated with an increase in mitochondrial fission in patients with diabetes. However, whether mitochondrial fission directly promotes diabetes-induced cardiac dysfunction is still unknown. Melatonin exerts a substantial influence on the regulation of mitochondrial fission/fusion. This study investigated whether melatonin protects against diabetes-induced cardiac dysfunction via regulation of mitochondrial fission/fusion and explored its underlying mechanisms. Here, we show that melatonin prevented diabetes-induced cardiac dysfunction by inhibiting dynamin-related protein 1 (Drp1)-mediated mitochondrial fission. Melatonin treatment decreased Drp1 expression, inhibited mitochondrial fragmentation, suppressed oxidative stress, reduced cardiomyocyte apoptosis, improved mitochondrial function and cardiac function in streptozotocin (STZ)-induced diabetic mice, but not in SIRT1-/- diabetic mice. In high glucose-exposed H9c2 cells, melatonin treatment increased the expression of SIRT1 and PGC-1α and inhibited Drp1-mediated mitochondrial fission and mitochondria-derived superoxide production. In contrast, SIRT1 or PGC-1α siRNA knockdown blunted the inhibitory effects of melatonin on Drp1 expression and mitochondrial fission. These data indicated that melatonin exerted its cardioprotective effects by reducing Drp1-mediated mitochondrial fission in a SIRT1/PGC-1α-dependent manner. Moreover, chromatin immunoprecipitation analysis revealed that PGC-1α directly regulated the expression of Drp1 by binding to its promoter. Inhibition of mitochondrial fission with Drp1 inhibitor mdivi-1 suppressed oxidative stress, alleviated mitochondrial dysfunction and cardiac dysfunction in diabetic mice. These findings show that melatonin attenuates the development of diabetes-induced cardiac dysfunction by preventing mitochondrial fission through SIRT1-PGC1α pathway, which negatively regulates the expression of Drp1 directly. Inhibition of mitochondrial fission may be a potential target for delaying cardiac complications in patients with diabetes.

High-titer n-butanol production by clostridium acetobutylicum JB200 in fed-batch fermentation with intermittent gas stripping.

Abstract: Acetone–butanol–ethanol (ABE) fermentation with a hyper-butanol producing Clostridium acetobutylicum JB200 was studied for its potential to produce a high titer of butanol that can be readily recovered with gas stripping. In batch fermentation without gas stripping, a final butanol concentration of 19.1 g/L was produced from 86.4 g/L glucose consumed in 78 h, and butanol productivity and yield were 0.24 g/L h and 0.21 g/g, respectively. In contrast, when gas stripping was applied intermittently in fed-batch fermentation, 172 g/L ABE (113.3 g/L butanol, 49.2 g/L acetone, 9.7 g/L ethanol) were produced from 474.9 g/L glucose in six feeding cycles over 326 h. The overall productivity and yield were 0.53 g/L h and 0.36 g/g for ABE and 0.35 g/L h and 0.24 g/g for butanol, respectively. The higher productivity was attributed to the reduced butanol concentration in the fermentation broth by gas stripping that alleviated butanol inhibition, whereas the increased butanol yield could be attributed to the reduced acids accumulation as most acids produced in acidogenesis were reassimilated by cells for ABE production. The intermittent gas stripping produced a highly concentrated condensate containing 195.9 g/L ABE or 150.5 g/L butanol that far exceeded butanol solubility in water. After liquid–liquid demixing or phase separation, a final product containing ∼610 g/L butanol, ∼40 g/L acetone, ∼10 g/L ethanol, and no acids was obtained. Compared to conventional ABE fermentation, the fed-batch fermentation with intermittent gas stripping has the potential to reduce at least 90% of energy consumption and water usage in n-butanol production from glucose. Biotechnol. Bioeng. 2012; 109: 2746–2756. © 2012 Wiley Periodicals, Inc.

TiO2−Multiwalled Carbon Nanotube Heterojunction Arrays and Their Charge Separation Capability

Abstract: Aligned multiwalled carbon nanotubes (MWNTs) coated with TiO2 nanoparticles were fabricated on a titanium foil by atmospheric pressure chemical vapor deposition (CVD). Their morphology was characte...

Integrating plasmonic nanoparticles with TiO₂ photonic crystal for enhancement of visible-light-driven photocatalysis.

Abstract: Aimed at enhancing photocatalysis through intensifying light harvesting, a new photocatalyst was fabricated by infiltrating Au nanoparticles into TiO2 photonic crystals (TiO2 PC/Au NPs). Scanning electron microscopy (SEM) and transmission electron microscope (TEM) images showed that the Au NPs with average diameter around 15 nm were dispersed uniformly into the porous TiO2 material. The results of the transmittance spectra demonstrated that the light absorption by Au NPs was amplified after they were infiltrated into TiO2 240, which was fabricated from 240 nm polystyrene spheres. In the photocatalytic experiments of 2,4-dichlorophenol degradation under visible light (λ > 420 nm) irradiation, the kinetic constant using TiO2 240/Au NPs was 2.3 fold larger than that using TiO2 nanocrystalline/Au NPs (TiO2 NC/Au NPs). The excellent photocatalysis benefited from the cooperatively enhanced light harvesting owing to the localized surface plasmon resonance of Au NPs, which extended the light response spectra and ...