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Doxorubicin (DOX) is the most effective and extensively used treatment for many tumors. However, its clinical use is hampered by its cardiotoxicity. DOX-induced mitochondrial dysfunction, which causes reactive oxygen species (ROS) generation, cardiomyocyte death, bioenergetic failure, and decreased cardiac function, is a very important mechanism of cardiotoxicity. These cellular processes are all linked by mitochondrial sirtuins (SIRT3-SIRT4). Mitochondrial sirtuins preserve mitochondrial function by increasing mitochondrial metabolism, inhibiting ROS generation by activating the antioxidant enzyme manganese-dependent superoxide dismutase (MnSOD), decreasing apoptosis by activating the forkhead homeobox type O (FOXO) and P53 pathways, and increasing autophagy through AMP-activated protein kinase (AMPK)/mTOR signaling. Thus, sirtuins function at the control point of many mechanisms involved in DOX-induced cardiotoxicity. In this review, we focus on the role of mitochondrial sirtuins in mitochondrial biology and DOX-induced cardiotoxicity. A further aim is to highlight other mitochondrial processes, such as autophagy (mitophagy) and mitochondrial quality control (MQC), for which the effect of mitochondrial sirtuins on cardiotoxicity is unknown.

Purpose: Nanomicelles (NMs) have been widely used for various biomedical applications due to its unique physiochemical properties. The present study aims to investigate the effects of vascular cell adhesion molecule-1 (VCAM-1)-targeted and peroxisome proliferator-activated receptor δ (PPARδ) agonist (GW0742)-loaded NMs on apoptosis and migration in oxidized low-density lipoprotein (ox-LDL)-induced human aortic vascular smooth muscle cells (HAVSMCs). Methods: The GW0742-loaded NMs (M-GW) and VCAM-1-targeted NMs loaded with GW0742 (TM-GW) were prepared, and then the morphologies and the size distribution of M-GM and TM-GM were observed by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. In vitro drug release assay of M-GM and TM-GM were performed as well. Next, HAVSMCs were cultured in medium containing ox-LDL to mimic atherosclerotic environment, and the effects of free GW0742, M-GM and TM-GM on endocytosis, cell migration and apoptosis, as well as the expression of VCAM-1, and proteins associated with migration and apoptosis were measured in HAVSMCs treated with ox-LDL. Results: M-GM and TM-GM were successfully prepared. VCAM-1 was overexpressed in HAVSMCs treated with ox-LDL, and TM-GM had a strong targeting ability to HAVSMCs treated with ox-LDL compared with M-GM. In addition, compared with free GW0742, both M-GM and TM-GM significantly diminished cell apoptosis and migration in HAVSMCs treated with ox-LDL. Conclusions: TM-GM had a superior suppressing effect on apoptosis and migration of ox-LDL-induced HAVSMCs.

A direct-current, atmospheric pressure, cold plasma microjet (PMJ) sustained in a quasi-steady gas cavity in liquid was used to inactivate Staphylococcus aureus suspended in distilled water. While helium gas (with 2% O 2 as additive) was used as working gas, an effective inactivation (>99%) was achieved in 6 min. The inactivation of bacteria was further verified by surface morphology examination and LIVE/ DEAD Baclight bacterial viability test (fluorescence microscopy). The overall pH and temperature of the liquid were monitored during the plasma treatment and were found to be below the critical values for the survival of S. aureus. Hydroxyl radical ( * OH) was detected via electron spin resonance (ESR) spectroscopy, and alongside other intermediate reactive species, is attributed to the effective inactivation of S. aureus. End-on optical emission spectroscopy show strong atomic oxygen emission both in air and in water.

Objective A direct-current, cold atmospheric-pressure air plasma microjet (PMJ) was performed to inactivate Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis) in air. The process of sterilization and morphology of bacteria was observed. We wish to know the possible inactivation mechanisms of PMJ and explore a potential application in dental and other temperature sensitive treatment. Methods In this study, we employed a direct current, atmospheric pressure, cold air PMJ to inactivate bacterias. Scanning electron microscopy was employed to evaluate the morphology of S. aureus and showed rupture of cell walls after the plasma treatment and Optical emission spectrum (OES) were used to understand the possible inactivation mechanisms of PMJ. Results The inactivation rates could reach 100% in 5 min. When the distance between the exit nozzle of the PMJ device and Petri dish was extended from 1 cm to 3 cm, effective inactivation was also observed with a similar inactivation curve. Conclusion The inactivation of bacteria is attributed to the abundant reactive oxygen and nitrogen species, as well as ultroviolet radiation in the plasma. Different life spans and defensibilities of these killing agents may hold the key to understanding the different inactivation curves at different treatment distances.

A direct-current, cold-atmospheric-pressure air plasma microjet (PMJ) sustained in a quasi-steady gas cavity in a liquid medium is used to inactivate Staphylococcus aureus (S. aureus) suspended in the liquid. The temperature and the pH value of the liquid change to steady-state values of about 40 °C and 3.0–4.5, respectively, after 10 min of plasma treatment. The decrease in the pH is attributed to the reaction of NOx produced in the air plasma with water at the gas–liquid interface. The concentrations of NO and NO are measured to be 37 mg · L−1 and 21 mg · L−1, respectively, after a 20 min of plasma treatment. Effective inactivation of S. aureus is found to start after the pH values decreases to about 4.5. This is attributed to the high oxidizing potential of the perhydroxyl radical (HOO•) on the fatty acid in the cell membranes of the microorganisms in the liquid.

The absorption spectra of the praseodymium complex with 1-cyclopropyl-6-fluoro-1,4-dihydro-7-(4-ethyl-1-piperazinyl)-4-oxo-3- quinoline carboxylic acid hydrochloride (NNFX) has been studied by normal and derivative spectrophotometry. The complex showed maximum absorption at 350 nm at pH 6.0. The stoichiometry of the Pr-NNFX complex was calculated by the molar ratio and continuous variation methods. The ratio of Pr to NNFX was 1:3. The absorption bands of the 4f electron transitions of the praseodymium complex with NNFX are enhanced markedly, especially the wavelength at 481 nm. Using the third-derivative spectrum, the calibration graph is linear over the range 2.5 x 10(-5)-3.5 x 10(-4) mol dm-3 for praseodymium. The detection limits (signal-to-noise ratio of 2) is 1.4 x 10(-6) mol dm-3. The relative standard deviation is 1.2% for 7.0 x 10(-5) mol dm-3 of praseodymium. A method for the direct determination of praseodymium in rare earth mixtures with good accuracy and selectivity is described.

Summary form only given. Aqueous environments are susceptible to contamination by bacteria, protozoa and viruses, which are the root cause of various illnesses. These contaminations are usually treated by chemical methods. Recently, attempts have been made to inactivate bacteria in water with non-thermal plasmas using various approaches, e.g., a pulsed streamer discharge plasma or a gliding arc discharge plasma. A direct-current, cold, atmospheric-pressure He/O2 plasma microjet (PMJ) sustained in a quasi-steady gas cavity in the liquid phase was used here to inactivate Staphylococcus aureus (S. aureus, suspended in a liquid). Effective inactivation (>98%) was achieved within the first 6 minutes of the PMJ treatment. The inactivation of the bacteria was verified by surface morphology examination (SEM) and by a LIVE/DEAD Baclight bacterial viability test (fluorescence microscopy). The overall pH and temperature of the liquid were observed to change from 7.5 to 6.2 and from 22°C to 30°C, respectively. A high concentration of OH was detected in the liquid by electron spin resonance (ESR) spectroscopy. End-on optical emission spectroscopy showed strong oxygen emission from the water.

Recently, a few attempts have been reported to inactivate bacteria in aqueous environments. Although effective inactivation of bacteria in their vegetative state (suspended in water) by non-thermal plasmas in or near the water has been reported, few studies have observed effective inactivation of bacterial spores.

Formocresol and calcium hydroxide are commonly used as the clinical disinfectant of root canals. Although they have strong chemical disinfection properties, their cytotoxic effects have always been a concern. E. faecalis, which is responsible for root canal failure, can also cause life-threatening infections in humans, especially in the nosocomial (hospital) environment, where naturally high levels of antibiotic-resistance towards E. faecalis are found and contribute to its pathogenicity.