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Bacterial vaginosis (BV) is the most common vaginal infection found in women in the world. Due to increasing drug‐resistance of virulent pathogen such as Gardnerella vaginalis (G. vaginalis), more than half of BV patients suffer recurrence after antibotics treatment. Here, metastable iron sulfides (mFeS) act in a Gram‐dependent manner to kill bacteria, with the ability to counteract resistant G. vaginalis for BV treatment. With screening of iron sulfide minerals, metastable Fe3S4 shows suppressive effect on bacterial growth with an order: Gram‐variable G. vaginalis >Gram‐negative bacteria>> Gram‐positive bacteria. Further studies on mechanism of action (MoA) discover that the polysulfide species released from Fe3S4 selectively permeate bacteria with thin wall and subsequently interrupt energy metabolism by inhibiting glucokinase in glycolysis, and is further synergized by simultaneously released ferrous iron that induces bactericidal damage. Such multiple MoAs enable Fe3S4 to counteract G. vaginalis strains with metronidazole‐resistance and persisters in biofilm or intracellular vacuole, without developing new drug resistance and killing probiotic bacteria. The Fe3S4 regimens successfully ameliorate BV with resistant G. vaginalis in mouse models and eliminate pathogens from patients suffering BV. Collectively, mFeS represent an antibacterial alternative with distinct MoA able to treat challenged BV and improve women health. [ABSTRACT FROM AUTHOR]

Cuprous halides, best described as (CuX)n (X = Cl−, Br−, and I−) in their solid state, catalyse selective aerobic oxidation of alcohols with the assistance of both NMI (N‐methylimidazole) and TEMPO (2,2,6,6‐tetramethylpiperidine‐1‐oxyl), and the iodide generally demonstrates the highest activity, for example, in the oxidation of 1‐octanol at ambient temperature under 24 h' reaction. However, in the aerobic oxidation of benzylic alcohols, the chloride showed superiority to the iodide in that the aerobic oxidation was quantitatively completed within 3 h at ambient temperature whereas the iodide showed only about half the activity of the chloride analogue. By probing the system using electrochemistry, electric conductivity, and 1H NMR titration, it was revealed that the surprising anomaly was due to the difference in the rate of forming active species, [Cu (NMI)2X(MeCN)], from the polymeric solid in a two‐stage process. Substrates expansion of 11 benzylic alcohols indicated that CuCl/NMI/TEMPO system demonstrated quantitative conversion of benzylic alcohols into corresponding aldehydes within 3 h and showed great tolerance to the substituents on the phenyl ring of the substrates. Furthermore, electron‐withdrawing substituent was beneficial to the oxidation and could offset the steric effect at orthro‐substituent. Such a behaviour suggested that in the catalysis, increasing the acidity of the hydroxyl group (OH) of the substrates could ease the oxidation, which implied that the deprotonation via an internal pathway might be one of the rate‐determining steps. Our results also showed that the anion halide participated actively in the catalysis by coordinating to Cu(I) in the active species. [ABSTRACT FROM AUTHOR]

A direct current atmospheric pressure cold plasma microjet (PMJ) was used to produce plasma activated water (PAW) in two generation modes above (PAW-A) and beneath (PAW-B) the water surface. The physicochemical characteristics and biological effects of them were measured respectively. Results showed that PAW-B exhibited stronger disinfection efficiency than PAW-A, which was associated with ORP and conductivity, but not pH value, temperature, H2O2, NO3− or NO2−. Furthermore, the cell membrane integrity and membrane potential of S. aureus were destroyed more severely by PAW-B. More importantly, a significant increase of intracellular ROS was induced by PAW-B, which was supposed to contribute most to the sterilization. This work provides valuable guidance for the production and wide applications of PAW. [ABSTRACT FROM AUTHOR]

With the development of plasma medicine, safety issues are emerging as a serious concern. In this study, the protective effects of live yeast cell derivative (LYCD) on yeast ( Saccharomyces cerevisiae) and mammalian cells (NIH-3T3) subjected to plasma treatment were investigated. The anti-oxidative properties of LYCD were assessed by analyzing three important antioxidants: superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). The results show that LYCD can efficiently protect the S. cerevisiae and NIH-3T3 cells against plasma treatment by elevating the survival ratio from 7 to 60% and 10 to 60%, respectively, and reverse the increased intracellular reactive oxygen species production following plasma exposure. Additionally, the protection is shown to be specific when compared with UV and H2O2 treatment. SOD and CAT activities as well as GSH content of LYCD increase linearly with plasma induction time. Simultaneously, the LYCD protection efficacies are increasing with longer plasma induction time, indicating that SOD, CAT, and GSH all contribute to the protective effect of LYCD. This work suggests that the non-toxic LYCD can serve as a promising precaution agent to enhance the safety of plasma applied directly to human body in the future. [ABSTRACT FROM AUTHOR]