Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Pulmonary electrical impedance tomography (EIT), a noninvasive, continuous, dynamic, and radiation-free bedside imaging technique for monitoring pulmonary ventilation, is now widely utilized in the diagnosis and management of critically ill patients. Beyond ventilation monitoring, hypertonic saline contrast-enhanced EIT for bedside pulmonary perfusion assessment has recently garnered significant attention. This article describes the application of hypertonic saline contrast-enhanced EIT to evaluate pulmonary perfusion in two patients following pulmonary endarterectomy, providing a reference for its perioperative application in such patients.

Inflammatory diseases (IDs) are a general term of diseases characterized by chronic inflammation as the primary pathogenetic mechanism, which seriously affect the quality of patient′s life and cause significant social and medical burden. Current drugs for IDs include nonsteroidal anti-inflammatory drugs, corticosteroids, immunomodulators, biologics, and antioxidants, but these drugs may cause gastrointestinal side effects, induce or worsen infections, and cause non-response or intolerance. Given the outstanding performance of metal polyphenol network (MPN) in the fields of drug delivery, biomedical imaging, and catalytic therapy, its application in the diagnosis and treatment of IDs has attracted much attention and significant progress has been made. In this paper, we first provide an overview of the types of IDs and their generating mechanisms, then sort out and summarize the different forms of MPN in recent years, and finally discuss in detail the characteristics of MPN and their latest research progress in the diagnosis and treatment of IDs. This research may provide useful references for scientific research and clinical practice in the related fields.

T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

Objective To determine the acetylation level of nucleophosmin(NPM)in female breast cancer and to discuss its function through mutation of modified lysine sites.To construct positive and negative NPM mutants on its acetylated lysine sites and to express them in breast cancer cells.Methods Acetylation level and acetylated lysine sites of NPM in three breast cancer tissues and para-carcinoma tissues were detected by acetylome technology;NPM mutants were constructed by site-directed mutagenesis PCR,specific PCR products were digested by DpnI and transformed into Escherichia coli(E.coli)to obtain specific plasmids for mutants;The accuracy of mutants were verified by double restriction enzyme digestion and sequencing;The mutants were expressed in BT-549 cells by transient transfection and verified by RT-PCR method.Protein expression and acetylation level of NPM were validated by Western blotting;Function of NPM acetylation was analyzed by proteomic detection and bioinformatic analysis.Results The 27th and 32nd lysine of NPM were highly acetylated in breast cancer tissues,which were 2.76 and 2.22 times higher than those in adjacent normal tissues,respectively;The NPM mutants showed the same molecular weight as that of wild type NPM and contained expected mutation sites;Corresponding NPM mRNA levels of BT-549 cells transfected with NPM mutants were significantly increased.With the increase of wild type NPM expression level,NPM acetylation level increased,while decreased after 27th lysine underwent negative mutation.NPM acetylation can significantly change the expression levels of 101 proteins in BT-549 cells,which are enriched in regulation of cellular macromolecule biosynthesis,DNA-template transcription,RNA biosynthesis and RNA metabolism process.Conclusion NPM is highly acetylated in breast cancer and can play a key role in cellular macromolecule biosynthesis,DNA-templated transcription,RNA biosynthesis and RNA metabolism process.

Objective:The preliminary results was reported regarding the treatment of mesenteric torsion by mesenteric fixation in the last decade, especially preventing recurrence of mesenteric torsion by mesenteric fan-shaped fixation.Methods:We selected 12 patients who received emergency operation in Chongqing Hospital of the First Affiliated Hospital of Guangzhou University of Chinese Medicine from December 2010 to March 2022. All of them were made a definite diagnose of mesenteric torsion by the preoperative CT scan or exploratory laparotomy. The recurrence of mesenteric torsion will be prevented by taking the operation of mesenteric fan-shaped fixation. This technique is suitable for the patient who is suffering total mesenteric torsion, but enteric necrosis is excluded affirmatively. The operation is consists of the following progress: (1) Exploratory laparotomy to check for necrosis of the bowel and for lesions other than torsion. (2) Mesenteric torsion derotation.(3) Mesenteric linear fixation; the right posterior lower border of the small mesentery (terminal ileal mesentery) is intermittently sutured to the posterior peritoneum of the right lower quadrant to increase the width of the base of the small mesentery. (4) Mesenteric fan-shaped fixation, which is fan-shaped to the lower left and fixed in the posterior peritoneum, shortening the length of the mesentery and further increasing the width of the mesentery and posterior peritoneal fixation.Results:A total of 12 patients with mesenteric torsion were treated by operation for 15 times in all. Among them, 3 cases received resection of most small bowel were performed without recurrence; 3 patients received only derotation for a total of 4 times, 2 cases recurred, 1 of them recurred twice; 4 cases underwent derotation and mesenteric linear fixation,and 1 case recurred. Four patients with derotation and mesenteric fan-shaped fixation recovered well without recurrence.Conclusion:Mesenteric fan-shaped fixation may be an effective operative type to reduce or avoid postoperative recurrence of mesenteric torsion.

Glucose-6-phosphate dehydrogenase (G6PD) is the first rate-limiting enzyme of the pentose phosphate pathway, which regulates the production of nicotinamide adenine dinucleotide phosphate (NADPH) in cells, and plays an important role in redox reactions. In addition, NADPH is necessary for biosynthesis reactions and is an essential hydrogen donor in the biosynthesis of cholesterol, fatty acids, and sex hormones. NADPH also plays an important role in maintaining intracellular redox homeostasis, converting intracellular oxidized glutathione into reduced glutathione (GSH), which is the main intracellular antioxidant. Therefore, G6PD plays an important role in maintaining intracellular redox homeostasis. Studies have shown that the decrease in G6PD activity can lead to a breakdown of the redox balance in the cells and tends to the oxidation state, which not only leads to dysregulation of cell growth and signaling, but also makes the host more susceptible to viruses. Previous studies have focused on the molecular characteristics of G6PD, anemia caused by G6PD deficiency, and the relationship between malignant tumors and G6PD. In recent years, more attentions have been paid to the importance of G6PD at the cellular level, development, and disease progression. To explore the effects of G6PD on viral life cycle, the relationship between G6PD and viral infections, including the clinical symptoms and virus-host interactions of hepatitis B virus (HBV), human papilloma virus (HPV), hepatitis E virus (HEV), influenza virus and dengue fever virus (DENV) will be reviewed, which will benefit the antiviral drugs development. Many studies had proved that patients with deficient G6PD are more susceptible to HBV infection. It has been reported that HBV infection activates the glycolytic pathway, promotes pentose phosphate pathway, and accelerates citric acid cycle to enhance nucleotide and fat biosynthesis, thereby promoting viral replication. During HPV infection, miR-206 up-regulates the expression of G6PD to facilitate viral replication. Thus, G6PD may be a new target for anti-cervical cancer therapy. It was reported that patients with G6PD deficiency are more susceptible to HEV infection, and more serious HEV infection-associated diseases are developed. However, the mechanism of why and how the deficiency of G6PD affect HEV infection is still unclear. The oxidative stress caused by G6PD deficiency provides a suitable environment for influenza virus replication. Furthermore, patients with G6PD deficiency are more susceptible to SARS-CoV-2 infection and lead to more severe clinical symptoms with a higher risk of thrombosis and hemolysis than general population. There is a correlation between DENV infection and G6PD deficiency, which increase the risk of hemolysis, however, the pathogenesis is still unknown. The deficiency of G6PD promotes HCoV 229E infection, possibly because the NF-κB signal pathway is suppressed when G6PD deficiency, which results in decreased innate antiviral immune, and increased susceptibility to HCoV 229E, finally leads to increased viral replication. Thus, the deficiency of G6PD play an important role during viruses’ infection, especially the susceptibility. More studies should be performed on the relicationship between G6PD deficiency and specific viral susceptibility, and more attentions shoud be paid to G6PD deficient patients, which will benefit the treatment of viral infection and the development of antiviral drugs.

3ʹ-Hydroxy-4ʹ-methoxy-2-hydroxy-5-bromochalcone (hereinafter referred to as C13) is a novel chalcone derivative obtained in the process of structural modification of DHMMF, the antitumor active compound of Resina Draconis, in our laboratory. In this study, we investigated the effects of C13 on the proliferation and apoptosis of human gastric cancer HGC-27 and AGS cells and its potential mechanism of action. Firstly, through methyl thiazolyl tetrazolium (MTT), colony formation assay, and 5-ethynyl-2'-deoxyuridine (EdU) staining, we found that C13 inhibited the proliferation ability of human gastric cancer HGC-27 and AGS cells. Using flow cytometry and Western blot, it was found that C13 induced apoptosis in human gastric cancer HGC-27 and AGS cells, and up-regulated the protein level of cleaved poly ADP-ribose polymerase (cleaved-PARP). The results of RNA sequencing analysis showed that the Erb-b2 receptor tyrosine kinase 4/phosphoinositide 3-kinases/AKT (ErbB4/PI3K/AKT) signaling pathway may be involved in anti-gastric cancer activity of C13. Finally, the results of immunoblotting assay showed that C13 treatment down-regulated the protein levels of ErbB4 and phospho-ErbB4, as well as down-regulated the phosphorylation levels of PI3K and AKT in human gastric cancer HGC-27 and AGS cells, which verified the results from RNA-seq analysis. In conclusion, C13 inhibited the proliferation and induced apoptosis of human gastric cancer cells, which may be related to the down-regulation of ErbB4/PI3K/AKT signaling pathway. This study may provide a candidate drug for the treatment of gastric cancer.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.