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Infectious diseases have been jeopardized problem that threaten public health over a long period of time. The growing prevalence of drug‐resistant pathogens and infectious cases have led to a decrease in the number of effective antibiotics, which highlights the urgent need for the development of new antibacterial agents. Serine acetyltransferase (SAT), also known as CysE in certain bacterial species, and O‐acetylserine sulfhydrylase (OASS), also known as CysK in select bacteria, are indispensable enzymes within the cysteine biosynthesis pathway of various pathogenic microorganisms. These enzymes play a crucial role in the survival of these pathogens, making SAT and OASS promising targets for the development of novel anti‐infective agents. In this comprehensive review, we present an introduction to the structure and function of SAT and OASS, along with an overview of existing inhibitors for SAT and OASS as potential antibacterial agents. Our primary focus is on elucidating the inhibitory activities, structure–activity relationships, and mechanisms of action of these inhibitors. Through this exploration, we aim to provide insights into promising strategies and prospects in the development of antibacterial agents that target these essential enzymes. [ABSTRACT FROM AUTHOR]

The variation law of concrete surface resistivity is studied in this paper, by changing five different factors such as fine aggregate type, fly ash and slag powder content, water-cement ratio, ambient temperature and curing method, which lays the foundation for the application of surface resistivity in concrete engineering. The research results show that: under the same age and the same maintenance mode, the change of fine aggregate type has basically no effect on the surface resistivity of concrete; the change in the amount of fly ash and slag powder has some influence on the concrete surface resistivity, but the degree of influence is small; changes in water-cement ratio and ambient temperature have a greater effect on the concrete surface resistivity. The change law of resistivity varies with the age, whether it is in the wet curing mode or the dry curing mode, and the curing mode has a great influence on the concrete surface resistivity. [ABSTRACT FROM AUTHOR]

Abstract With its fine immunity to multipath fading, ultra-wideband (UWB) is considered to be a potential technique in constructing intravehicle wireless sensor networks. In the UWB literature, extensive measuring and modeling work have been done for indoor or outdoor propagation, but very few measurements were performed in intravehicle environments. This paper reports our effort in measuring and modeling the UWB propagation channel in commercial vehicle environment. In our experiment, channel sounding is performed in time domain for two environments. In one environment, the transmitting and the receiving antennas are put beneath the chassis. In another environment, both antennas are located inside the engine compartment. It is observed that paths arrive in clusters in the latter environment but such clustering phenomenon does not exist in the former case. Different multipath models are used to describe the two different propagation channels. For the engine compartment environment, we describe the multipath propagation with the classical S-V model. And for the chassis environment, the channel impulse response is just represented as the sum of multiple paths. Observation reveals that the power delay profile (PDP) in this environment does not start with a sharp maximum but has a rising edge. A modified S-V PDP model is used to account for this rising edge. Based on the analysis of the measured data, channel model parameters are extracted for both environments.

This article selects R·SAC as the filler for emulsified asphalt mixture,through orthogonal design,the construction workability and pavement performance of R·SAC-emulsified asphalt mixture are studied based on the three factors of cement content, external water content and oil-stone ratio,and the influencing degree of different factors on the performance of the emulsified asphalt mixture is analyzed. SEM is adopted to conduct microscopic analysis of its internal structure to explore the improvement mechanism of R·SAC on the strength of emulsified asphalt mixture. The results show that the R·SAC content has the greatest impact on the emulsified asphalt demulsification time and the pavement performance of R-SAC-emulsified asphalt mixture. The oil stone ratio has the greatest influence on the push-in force of R·SAC-emulsified asphalt mixture. The increase of R-SAC content is conducive to the early opening of traffic and the improvement of pavement bearing capacity and resistance to deformation. [ABSTRACT FROM AUTHOR]

More and more extrachromosomal DNA (ecDNA) was found in human tumor cells in recent years, which has a high copy number in tumors and changes the expression of oncogenes, thus different from normal chromosomal DNA. These circular structures were identified to originate from chromosomes, and play critical roles in rapid carcinogenesis, tumor evolution and multidrug resistance. Therefore, this review mostly focuses on the biogenesis and regulation of extrachromosomal oncogene in ecDNA as well as its function and mechanism in tumors, which are of great significance for our comprehensive understanding of the role of ecDNA in tumor carcinogenic mechanism and are expected to provide ecDNA with the potential to be a new molecular target for the diagnosis and treatment of tumors., Competing Interests: None., (AJCR Copyright © 2020.)

Breast cancer, the second most common cancer worldwide, is the leading cause of cancer-associated mortality in women, accounting for ~15% of all cancer-associated mortalities in women. The development, local invasion and metastasis of breast cancer are associated with the dysregulation and mutation of numerous genes and epigenetic mechanisms, including coding RNA and non-coding RNA, such as microRNAs (miRs/miRNAs). Previous studies have shown a dual-faced role of miR-125b in breast cancer. In the present study, a total of 221 paraffin-embedded breast cancer and 49 paraffin-embedded non-cancerous breast tissue samples were collected. In situ hybridization was used to analyze the expression of miR-125b in the breast cancer tissues. Spearman's rank correlation analysis was used to analyze the expression correlation between miR-125b and human epidermal growth factor 2 (HER2). The overall survival estimates over time were calculated using the Kaplan-Meier method with log-rank test. It was found that miR-125b expression was significantly increased in the breast cancer tissues compared with that in the non-cancerous tissues, and high miR-125b expression indicated a poor prognosis in the breast cancer patients. In addition, miR-125b expression was positively correlated with HER2, but not with progesterone receptor and estrogen receptor. Notably, high miR-125b expression was significantly correlated with tumor size and Tumor-Node-Metastasis stage in the HER2-positive breast cancer patients, along with a poor prognosis. The present study provides clinical data to confirm the oncogenic potential of miR-125b, particularly in HER2-positive human breast cancer. Thus, identification of miR-125b may be a potential molecular biomarker for the prediction of clinical outcomes in breast cancer patients, particularly HER2-positive cases that will receive paclitaxel-based neoadjuvant chemotherapy.

Objective: To construct a eukaryotic expression vector of bromodomain-containing protein 7 (BRD7) with deletion of bromodomain (BRD7△brd) using the homologous recombination and reverse PCR amplification techniques., Methods: The linear DNA fragments of bromodomain-deleted mutation of BRD7 (pIRES2-EGFP- 3Flag/BRD7△brd) were amplified by one pair of reverse PCR primers using high-fidelity enzyme, and then these fragments were transformed into E.coli to obtain the eukaryotic expression vector expressing BRD7△brd protein based on homologous recombination and plasmid cyclization., Results: Bromodomain-deleted clones were identified by digestion with restrictive enzymes, and then the sequence and protein expression were further confirmed by sequencing and Western blot assays. The results suggest that pIRES2-EGFP-3Flag/BRD7△brd was successfully constructed., Conclusion: We establish a simple and quick method to construct plasmids with pIRES2-EGFP- 3Flag/BRD7△brd using reverse PCR amplification and homologous recombination techniques. We also found that the concentration of template in PCR reaction system is one of the critical factors that affect the rate of homologous recombination. Of all, this improved technique could be widely used in the construction of gene mutations.