Background: The threat of drug-resistant Pseudomonas aeruginosa requires great efforts to develop highly effective and safe bactericide. Objective: This study aimed to investigate the antibacterial activity and mechanism of silver nanoparticles (AgNPs) against multidrug-resistant P. aeruginosa. Methods: The antimicrobial effect of AgNPs on clinical isolates of resistant P. aeruginosa was assessed by minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). In multidrug-resistant P. aeruginosa, the alterations of morphology and structure were observed by the transmission electron microscopy (TEM); the differentially expressed proteins were analyzed by quantitative proteomics; the production of reactive oxygen species (ROS) was assayed by H2DCF-DA staining; the activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) was chemically measured and the apoptosis-like effect was determined by flow cytometry. Results: Antimicrobial tests revealed that AgNPs had highly bactericidal effect on the drug-resistant or multidrug-resistant P. aeruginosa with the MIC range of 1.406–5.625 µg/mL and the MBC range of 2.813–5.625 µg/mL. TEM showed that AgNPs could enter the multidrug-resistant bacteria and impair their morphology and structure. The proteomics quantified that, in the AgNP-treated bacteria, the levels of SOD, CAT, and POD, such as alkyl hydroperoxide reductase and organic hydroperoxide resistance protein, were obviously high, as well as the significant upregulation of low oxygen regulatory oxidases, including cbb3-type cytochrome c oxidase subunit P2, N2, and O2. Further results confirmed the excessive production of ROS. The antioxidants, reduced glutathione and ascorbic acid, partially antagonized the antibacterial action of AgNPs. The apoptosis-like rate of AgNP-treated bacteria was remarkably higher than that of the untreated bacteria (P<0.01). Conclusion: This study proved that AgNPs could play antimicrobial roles on the multidrug-resistant P. aeruginosa in a concentration- and time-dependent manner. The main mechanism involves the disequilibrium of oxidation and antioxidation processes and the failure to eliminate the excessive ROS.

The coronavirus disease 2019 (COVID-19) pandemic aroused global public concern and became a major medical issue. This study aims to investigate the global research routine and trends of coronavirus over the last twenty years based on the production, hotspots, and frontiers of published articles as well as to provide the global health system with a bibliometric reference. The Web of Science core collection database was retrieved for coronavirus articles published from 1 January 2000 to 17 March 2020. Duplicates and discrete papers were excluded. Analysis parameters including time, regions, impact factors, and citation times were processed through professional software. A total of 9043 coronavirus articles originated from 123 countries and were published in 1202 journals. The USA contributed most articles (3101) followed by China (2230). The research was published in specialized journals including the Journal of Virology. Universities were the main institutions of science progress. High-impact articles covered fields of basic science and clinical medicine. There were two sharp increases in research yields after the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS) outbreaks. International collaborations promoted study progress, and universities and academies act as the main force in coronavirus research. More research on prevention and treatment is needed according to an analysis of term density.

Dietary habits have been proven to help alter the composition of gut microbiota, and exploring the impact of nutritional patterns on gut microbiota changes can help protect gut health. However, few studies have focused on the dietary impact on the gut microbiota over an experimental timeframe. In this study, 16S rRNA gene sequencing was employed to investigate the gut microbiota of mice under different dietary patterns, including AIN-93G diet (Control), high protein diet (HPD), high fiber diet (HFD), and switch diet (Switch). The alpha diversity of the HPD group significantly decreased, but HFD can restore this decline. During HPD, some genera were significantly upregulated (e.g., Feacalibaculum) and downregulated (e.g., Parabacteroides). However, after receiving HFD, other genera were upregulated (e.g., Akkermansia) and downregulated (e.g., Lactobacillus). In addition, the interaction between pathogenic bacteria was more pronounced during HPD, while the main effect was probiotics during HFD. In conclusion, the plasticity exhibited by the gut microbiota was subject to dietary influences, wherein disparate dietary regimens hold pivotal significance in upholding the well-being of the host. Therefore, our findings provide new ideas and references for the relationship between diets and gut microbiota.

In 1991, researchers reported that a modest preovulatory increase in serum progesterone levels is associated with lower pregnancy rates and higher incidence of pregnancy loss in in vitro fertilization (IVF). We wonder whether embryo transfer (ET) in assisted reproductive technology (ART) cycles in patients with premature progesterone rise (PPR) have a negative impact on the clinical pregnancy rates (CPRs) and/or live birth rates (LBRs) in our series. Consequently, will blastocyst transfer reverse the negative impact? This noninterventional, retrospective, observational tertiary center study was conducted between January 2010 and December 2012. All fresh ET cycles with serum progesterone levels measured (n = 599) on the day of hCG administration were analyzed. Sera lutenizing hormone (LH), E2, and progesterone (P) were measured and analyzed. The CPRs of cycles in patients with p ≤ 1.5 ng/mL (low) versus those with p > 1.5 ng/mL (high) were 37.04% versus 41.03% [odds ratio (OR) = 1.18, 95% confidence interval (CI): 0.728-1.920; p = 0.50). The LBRs of cycles in patients with low progesterone level versus those with PPR were 30.52% versus 34.62% (OR = 1.21, 95% CI: 0.729-1.992; p = 0.47). No statistically significant association was detected. We further analyzed the outcomes according to different stages of ET and found that blastocyst (D5) ET significantly increase the LBRs as compared with cleavage stage (D2/D3) ET in the PPR group (44.44% versus 21.43%; p = 0.043). PPR did not significantly compromise the clinical outcomes in this series. However, shifting to blastocyst transfer probably could increase the live birth in cycles with PPR.