Nanomaterials with Glucose Oxidase-Mimicking Activity for Biomedical Applications.

Glucose oxidase (GOD) is an oxidoreductase that catalyzes the aerobic oxidation of glucose into hydrogen peroxide (H2O2) and gluconic acid, which has been widely used in industrial raw materials production, biosensors and cancer treatment. However, natural GOD bears intrinsic disadvantages, such as poor stability and a complex purification process, which undoubtedly restricts its biomedical applications. Fortunately, several artificial nanomaterials have been recently discovered with a GOD-like activity and their catalytic efficiency toward glucose oxidation can be finely optimized for diverse biomedical applications in biosensing and disease treatments. In view of the notable progress of GOD-mimicking nanozymes, this review systematically summarizes the representative GOD-mimicking nanomaterials for the first time and depicts their proposed catalytic mechanisms. We then introduce the efficient modulation strategy to improve the catalytic activity of existing GOD-mimicking nanomaterials. Finally, the potential biomedical applications in glucose detection, DNA bioanalysis and cancer treatment are highlighted. We believe that the development of nanomaterials with a GOD-like activity will expand the application range of GOD-based systems and lead to new opportunities of GOD-mimicking nanomaterials for various biomedical applications.

Knowledge, attitude, and practice associated with antimicrobial resistance among medical students between 2017 and 2022: A survey in East China.

This study described the knowledge, attitude, practice regarding antimicrobial resistance (AMR) among medical students between 2017 and 2022 in East China. A questionnaire-based survey was conducted with a total of 1,066 respondents. We highlighted that the undergraduates had a significant increase in the knowledge of antimicrobial resistance during the 5 years from 2017 to 2022 (p < 0.001). The majority of the assertions about the AMR were correctly identified by respondents. However, gaps were still observed in the issues of antimicrobial targets and bacterial transmission. In addition, overconfident attitudes and inappropriate behaviors of antimicrobial overuse and misuse were observed in the respondents. A number of 30.2% to 45.2% of the respondents asserted that there is no risk of AMR as long as the antimicrobials are taken correctly, and a proportion of the students (25.3% in 2022; 69.3% in 2017, p < 0.001) declared to buy antimicrobials from friends or family members to treat the same illness. Finally, spearman correlation coefficient was enrolled to compare the correlation of the student's KAP. Results showed that the students' knowledge of antimicrobials had a correlation with attitude (p = 0.0126) and practice (p < 0.001), suggesting that public education on knowledge could influence the behaviors among the medical students. Taken all together, our findings show a need to strengthen the medical students' cogitation on antimicrobial attitude and practice of appropriate usage as an essential strategy to reduce intractable public health problems. Additional curriculum reforms will be needed to add more specific AMR-related lectures to raise awareness amongst medical students in China.

Characteristics of population structure, antimicrobial resistance, virulence factors, and morphology of methicillin-resistant Macrococcus caseolyticus in global clades.

Macrococcus caseolyticus is an opportunistic pathogen that is frequently isolated from dairy products and veterinary infections. Recent studies have reported the possibility of methicillin resistance that be transferred among staphylococcal species in foods. The present study examined the population structure, antimicrobial resistance, virulence factors, and morphology of methicillin-resistant M. caseolyticus by investigation of 94 genomes derived from both isolates in beef (n = 7) and pork (n = 2) at Shanghai and those deposited in public domain (n = 85). Phylogenetically, M. caseolyticus were divided into four clades, which each consisted of genomes isolated from continent of European countries (82.4%, n = 78), Asian countries (11.3%, n = 10), United States (4.1%, n = 4), Australia (1%, n = 1), and Sudan (1%, n = 1). The M. caseolyticus isolated from present study formed a genetically distinguished clade, which was characterized by novel alleles in the traditional 7-gene MLST scheme. Furthermore, we identified 24 AMR genes that were associated with 10 classes of antimicrobial agents in M. caseolyticus. Most AMR genes were carried by dominant plasmids such as rep7a, rep22 and repUS56. The genomes in the global clades carried significantly less AMR genes (p < 0.05) and more virulence factors (p < 0.001) than present clade. Virulence factors were detected in methicillin resistant M. caseolyticus including genes coding hemolysin, adherence, biofilm formation, exotoxin, and capsule that associated to human health and infection. Finally, as the close relative of the genus Staphylococcus, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were performed for morphological comparison that M. caseolyticus has a larger diameter and thicker cell wall compared with S. aureus ATCC 25,923. Taken together, our study suggested that M. caseolyticus mediating divergent antimicrobial resistance and virulence factors could serve as the vector for methicillin resistance habitats in foodborne microorganisms.

Image-free real-time detection and tracking of fast moving object using a single-pixel detector.

Real-time detection and tracking for fast moving object has important applications in various fields. However, available methods, especially low-cost ones, can hardly achieve real-time and long-duration object detection and tracking. Here we report an image-free and cost-effective method for detecting and tracking a fast moving object in real time and for long duration. The method employs a spatial light modulator and a single-pixel detector for data acquisition. It uses Fourier basis patterns to illuminate the target moving object and collects the resulting light signal with a single-pixel detector. The proposed method is able to detect and track the object with the single-pixel measurements directly without image reconstruction. The detection and tracking algorithm of the proposed method is computationally efficient. We experimentally demonstrate that the method can achieve a temporal resolution of 1,666 frames per second by using a 10,000 Hz digital micro-mirror device. The latency time of the method is on the order of microseconds. Additionally, the method acquires only 600 bytes of data for each frame. The method therefore allows fast moving object detection and tracking in real time and for long duration. This image-free approach might open up a new avenue for spatial information acquisition in a highly efficient manner.

Lensless single-pixel imaging by using LCD: application to small-size and multi-functional scanner.

Single-pixel imaging commonly uses a spatial light modulator (SLM) to encode a scene's spatial information into a one-dimensional light signal sequence so that a single-pixel detector can be used to capture a scene. Digital micromirror device, liquid crystal on silicon, or light emitted diode matrix is a common choice of SLM, but it requires a certain lens system in order to project the structured light pattern that is generated by the SLM onto the scene. Using a lens would not only lead to aberration but also result in difficulty for establishing a compact imaging system. Therefore, we propose to use a liquid crystal display (LCD) as an intensity-only SLM to conduct structured illumination. As such, single-pixel imaging can be performed in a lensless way. As an instance of the proposed technique, a small-size and multi-functional scanner is designed and established to prove the lensless single-pixel imaging concept. As experimentally demonstrated, the single-pixel scanner can not only achieve grayscale and true-color scanning as a typical scanner does, but also achieve distinctive functionalities, such as accurate optical character recognition from under-sampled data, on-the-fly encryption, and genuine document identification. This compact scanner is as thin as 2.48 millimeters. The proposed lensless single-pixel imaging technique might find applications in various fields.