Background Kurtosis reflecting noise's temporal structure is an effective metric for evaluating noise-induced hearing loss (NIHL), and its threshold is still unclear. Objective To explore the energy range of kurtosis and the threshold of NIHL induced by kurtosis in this energy rangeMethods Using cross-sectional design, 4631 noise-exposed workers in manufacturing industry were selected. The hearing loss and noise exposure data of each worker were collected. Logistic regression model was used to establish the dose-response relationship between noise exposure and hearing loss and estimate the range of energy effects. Restricted cubic spline model was utilized to analyze the dose-response relationship curves of kurtosis to noise-induced hearing loss (NIHI) and high-frequency noise-induced hearing loss (HFNIHL) under different 8 h equivalent sound levels (L_{EX,8 h}), as well as to estimate the kurtosis effect threshold. Results The logistic regression model analysis showed that the prevalence of NIHI and HFNIHL increased significantly with increase of L_{EX,8 h} for steady noise; when L_{EX,8 h} of non-steady noise was 80-100 dB(A), the risk of hearing loss increased with an increase in kurtosis (P<0.05). The restricted cubic spline model showed that when L_{EX,8 h} of non-steady noise was 0-80 dB(A) or >100 dB(A), there was no significant relationship between kurtosis and NIHI or HFNIHL. When L_{EX,8 h} was 80-100 dB(A), there was a significant nonlinear dose-response relationship between kurtosis and NIHL or HFNIHL (P <0.001), and kurtosis > 28.08 exerted effect in elevating NIHI or HFNIHL. Conclusion The effect threshold of kurtosis on NIHL is 28.08 when non-steady noise levels are in the range of 80-100 dB(A). The effect threshold of kurtosis needs further verification.

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.

The current study aimed to clarify the roles of apolipoprotein A5 (ApoA5) and milk fat globule-epidermal growth factor 8 (Mfge8) in regulating myocardial lipid deposition and the regulatory relationship between them. The serum levels of ApoA5 and Mfge8 in obese and healthy people were compared, and the obesity mouse model induced by the high-fat diet (HFD) was established. In addition, primary cardiomyocytes were purified and identified from the hearts of suckling mice. The 0.8 mmol/L sodium palmitate treatment was used to establish the lipid deposition cardiomyocyte model in vitro. ApoA5-overexpressing adenovirus was used to observe its effects on cardiac function and lipids. The expressions of the fatty acid uptake-related molecules and Mfge8 on transcription or translation levels were detected. Co-immunoprecipitation was used to verify the interaction between ApoA5 and Mfge8 proteins. Immunofluorescence was used to observe the co-localization of Mfge8 protein with ApoA5 or lysosome-associated membrane protein 2 (LAMP2). Recombinant rMfge8 was added to cardiomyocytes to investigate the regulatory mechanism of ApoA5 on Mfge8. The results showed that participants in the simple obesity group had a significant decrease in serum ApoA5 levels (P < 0.05) and a significant increase in Mfge8 levels (P < 0.05) in comparison with the healthy control group. The adenovirus treatment successfully overexpressed ApoA5 in HFD-fed obese mice and palmitic acid-induced lipid deposition cardiomyocytes, respectively. ApoA5 reduced the weight of HFD-fed obese mice (P < 0.05), shortened left ventricular isovolumic relaxation time (IVRT), increased left ventricular ejection fraction (LVEF), and significantly reduced plasma levels of triglycerides (TG) and cholesterol (CHOL) (P < 0.05). In myocardial tissue and cardiomyocytes, the overexpression of ApoA5 significantly reduced the deposition of TG (P < 0.05), transcription of fatty acid translocase (FAT/CD36) (P < 0.05), fatty acid-binding protein (FABP) (P < 0.05), and fatty acid transport protein (FATP) (P < 0.05), and protein expression of Mfge8 (P < 0.05), while the transcription levels of Mfge8 were not significantly altered (P > 0.05). In vitro, the Mfge8 protein was captured using ApoA5 as bait protein, indicating a direct interaction between them. Overexpression of ApoA5 led to an increase in co-localization of Mfge8 with ApoA5 or LAMP2 in cardiomyocytes under lipid deposition status. On this basis, exogenous added recombinant rMfge8 counteracted the improvement of lipid deposition in cardiomyocytes by ApoA5. The above results indicate that the overexpression of ApoA5 can reduce fatty acid uptake in myocardial cells under lipid deposition status by regulating the content and cellular localization of Mfge8 protein, thereby significantly reducing myocardial lipid deposition and improving cardiac diastolic and systolic function.
Animals ; Humans ; Mice ; Myocytes, Cardiac/metabolism* ; Obesity/physiopathology* ; Male ; Apolipoprotein A-V/blood* ; Lipid Metabolism/physiology* ; Milk Proteins/blood* ; Myocardium/metabolism* ; Diet, High-Fat ; Antigens, Surface/physiology* ; Mice, Inbred C57BL ; Cells, Cultured ; Female

A primary hallmark of pathological cardiac hypertrophy is excess protein synthesis due to enhanced translational activity. However, regulatory mechanisms at the translational level under cardiac stress remain poorly understood. Here we examined the translational regulations in a mouse cardiac hypertrophy model induced by transaortic constriction (TAC) and explored the conservative networks versus the translatome pattern in human dilated cardiomyopathy (DCM). The results showed that the heart weight to body weight ratio was significantly elevated, and the ejection fraction and fractional shortening significantly decreased 8 weeks after TAC. Puromycin incorporation assay showed that TAC significantly increased protein synthesis rate in the left ventricle. RNA-seq revealed 1,632 differentially expressed genes showing functional enrichment in pathways including extracellular matrix remodeling, metabolic processes, and signaling cascades associated with pathological cardiomyocyte growth. When combined with ribosome profiling analysis, we revealed that translation efficiency (TE) of 1,495 genes was enhanced, while the TE of 933 genes was inhibited following TAC. In DCM patients, 1,354 genes were upregulated versus 1,213 genes were downregulated at the translation level. Although the majority of the genes were not shared between mouse and human, we identified 93 genes, including Nos3, Kcnj8, Adcy4, Itpr1, Fasn, Scd1, etc., with highly conserved translational regulations. These genes were remarkably associated with myocardial function, signal transduction, and energy metabolism, particularly related to cGMP-PKG signaling and fatty acid metabolism. Motif analysis revealed enriched regulatory elements in the 5' untranslated regions (5'UTRs) of transcripts with differential TE, which exhibited strong cross-species sequence conservation. Our study revealed novel regulatory mechanisms at the translational level in cardiac hypertrophy and identified conserved translation-sensitive targets with potential applications to treat cardiac hypertrophy and heart failure in the clinic.
Animals ; Humans ; Cardiomegaly/physiopathology* ; Ribosomes/physiology* ; Protein Biosynthesis/physiology* ; Mice ; Cardiomyopathy, Dilated/genetics* ; Ribosome Profiling

This study identified 8 members including NjBIN2 of the GSK3 family in Nardostachys jatamansi by bioinformatics analysis. Moreover, the phylogenetic tree revealed that the GKS3 family members of N. jatamansi had a close relationship with those of Arabidopsis. RT-qPCR results showed that NjBIN2 presented a tissue-specific expression pattern with the highest expression in roots, suggesting that NjBIN2 played a role in root growth and development. In addition, the application of epibrassinolide or the brassinosteroid(BR) synthesis inhibitor(brassinazole) altered the expression pattern of NjBIN2 and influenced the photomorphogenesis(cotyledon opening) and root development of N. jatamansi, which provided direct evidence about the functions of NjBIN2. In conclusion, this study highlights the roles of BIN2 in regulating the growth and development of N. jatamansi by analyzing the expression pattern and biological function of NjBIN2. It not only enriches the understanding about the regulatory mechanism of the growth and development of N. jatamansi but also provides a theoretical basis and potential gene targets for molecular breeding of N. jatamansi with improved quality in the future.
Brassinosteroids/metabolism* ; Steroids, Heterocyclic/metabolism* ; Gene Expression Regulation, Plant/drug effects* ; Plant Proteins/metabolism* ; Phylogeny ; Nardostachys/metabolism* ; Plant Growth Regulators/pharmacology* ; Plant Roots/drug effects*

This study aims to investigate the molecular mechanism by which naringin alleviates cerebral ischemia/reperfusion(CI/R) injury through DRP1/LRRK2/MCU signaling axis. A total of 60 SD rats were randomly divided into the sham group, the model group, the sodium Danshensu group, and low-, medium-, and high-dose(50, 100, and 200 mg·kg~(-1)) naringin groups, with 10 rats in each group. Except for the sham group, a transient middle cerebral artery occlusion/reperfusion(tMCAO/R) model was established in SD rats using the suture method. Longa 5-point scale was used to assess neurological deficits. 2,3,5-Triphenyl tetrazolium chloride(TTC) staining was used to detect the volume percentage of cerebral infarction in rats. Hematoxylin-eosin(HE) staining and Nissl staining were employed to assess neuronal structural alterations and the number of Nissl bodies in cortex, respectively. Western blot was used to determine the protein expression levels of B-cell lymphoma-2 gene(Bcl-2), Bcl-2-associated X protein(Bax), cleaved cysteine-aspartate protease-3(cleaved caspase-3), mitochondrial calcium uniporter(MCU), microtubule-associated protein 1 light chain 3(LC3), and P62. Mitochondrial structure and autophagy in cortical neurons were observed by transmission electron microscopy. Immunofluorescence assay was used to quantify the fluorescence intensities of MCU and mitochondrial calcium ion, as well as the co-localization of dynamin-related protein 1(DRP1) with leucine-rich repeat kinase 2(LRRK2) and translocase of outer mitochondrial membrane 20(TOMM20) with LC3 in cortical mitochondria. The results showed that compared with the model group, naringin significantly decreased the volume percentage of cerebral infarction and neurological deficit score in tMCAO/R rats, alleviated the structural damage and Nissl body loss of cortical neurons in tMCAO/R rats, inhibited autophagosomes in cortical neurons, and increased the average diameter of cortical mitochondria. The Western blot results showed that compared to the sham group, the model group exhibited increased levels of cleaved caspase-3, Bax, MCU, and the LC3Ⅱ/LC3Ⅰ ratio in the cortex and reduced protein levels of Bcl-2 and P62. However, naringin down-regulated the protein expression of cleaved caspase-3, Bax, MCU and the ratio of LC3Ⅱ/LC3Ⅰ ratio and up-regulated the expression of Bcl-2 and P62 proteins in cortical area. In addition, immunofluorescence analysis showed that compared with the model group, naringin and positive drug treatments significantly decreased the fluorescence intensities of MCU and mitochondrial calcium ion. Meanwhile, the co-localization of DRP1 with LRRK2 and TOMM20 with LC3 in cortical mitochondria was also decreased significantly after the intervention. These findings suggest that naringin can alleviate cortical neuronal damage in tMCAO/R rats by inhibiting DRP1/LRRK2/MCU-mediated mitochondrial fragmentation and the resultant excessive mitophagy.
Animals ; Rats, Sprague-Dawley ; Reperfusion Injury/genetics* ; Flavanones/administration & dosage* ; Rats ; Dynamins/genetics* ; Male ; Brain Ischemia/genetics* ; Protein Serine-Threonine Kinases/genetics* ; Signal Transduction/drug effects* ; Humans ; Drugs, Chinese Herbal/administration & dosage*

As an indispensable trace element in the human body,copper plays an important role in various physiological and biochemical reactions.The dyshomeostasis of copper leads to the disorder of copper metabolism and the occurrence of related diseases.Cuproptosis,a newly proposed regulatory cell death mode,is different from the known apoptosis,pyroptosis,necroptosis,and ferroptosis.Recent studies have found that the dyshomeostasis of copper has been observed in a variety of cancers.Therefore,targeting copper for disease treatment may become a new strategy and a new idea.This article systematically summarizes the fundamental properties of copper,copper dyshomeostasis-related diseases (Menkes syndrome,Wilson's disease,and cancer) and their treatment,and reviews the research progress in cuproptosis.
Humans ; Copper/metabolism* ; Homeostasis ; Neoplasms/metabolism* ; Hepatolenticular Degeneration/metabolism* ; Menkes Kinky Hair Syndrome/metabolism*

Activation of nuclear factor erythroid 2-related factor 2(Nrf2)by Kelch-like ECH-associated protein 1(Keap1)alkylation plays a central role in anti-inflammatory therapy.However,activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified.Deoxynyboquinone(DNQ)is a natural small molecule discovered from marine actinomycetes.The current study was designed to investigate the anti-inflammatory effects and molecular mechanisms of DNQ via alkylation of Keap1.DNQ exhibited signif-icant anti-inflammatory properties both in vitro and in vivo.The pharmacophore responsible for the anti-inflammatory properties of DNQ was determined to be the α,β-unsaturated amides moieties by a chemical reaction between DNQ and N-acetylcysteine.DNQ exerted anti-inflammatory effects through activation of Nrf2/ARE pathway.Keap1 was demonstrated to be the direct target of DNQ and bound with DNQ through conjugate addition reaction involving alkylation.The specific alkylation site of DNQ on Keap1 for Nrf2 activation was elucidated with a synthesized probe in conjunction with liquid chromatography-tandem mass spectrometry.DNQ triggered the ubiquitination and subsequent degra-dation of Keap1 by alkylation of the cysteine residue 489(Cys489)on Keap1-Kelch domain,ultimately enabling the activation of Nrf2.Our findings revealed that DNQ exhibited potent anti-inflammatory capacity through α,β-unsaturated amides moieties active group which specifically activated Nrf2 signal pathway via alkylation/ubiquitination of Keap1-Kelch domain,suggesting the potential values of targeting Cys489 on Keap1-Kelch domain by DNQ-like small molecules in inflammatory therapies.

Objective:To investigate the surgical situations and perioperative outcome of pancreaticoduodenectomy in Jiangsu Province and the influencing factors for postoperative 90-day mortality.Methods:The retrospective case-control study was conducted. The clinicopathological data of 2 886 patients who underwent pancreaticoduodenectomy in 21 large tertiary hospitals of Jiangsu Quality Control Center for Pancreatic Diseases, including The First Affiliated Hospital of Nanjing Medical University, from March 2021 to December 2022 were collected. There were 1 732 males and 1 154 females, aged 65(57,71)years. Under the framework of the Jiangsu Provincial Pancreatic Disease Quality Control Project, the Jiangsu Quality Control Center for Pancreatic Diseases adopted a multi-center registration research method to establish a provincial electronic database for pancrea-ticoduodenectomy. Observation indicators: (1) clinical characteristics; (2) intraoperative and post-operative conditions; (3) influencing factors for 90-day mortality after pancreaticoduodenectomy. Measurement data with skewed distribution were represented as M( Q1, Q3) or M(IQR), and comparison between groups was conducted using the Mann-Whitney U test. Count data were expressed as absolute numbers or constituent ratio, and comparison between groups was conducted using the chi-square test, continuity correction chi-square test and Fisher exact probability. Maximal Youden index method was used to determine the cutoff value of continuous variables. Univariate analysis was performed using the corresponding statistical methods based on data types. Multivariate analysis was performed using the Logistic multiple regression model. Results:(1) Clinical characteristics. Of the 2 886 patients who underwent pancreaticoduodenectomy, there were 1 175 and 1 711 cases in 2021 and 2022, respectively. Of the 21 hospitals, 8 hospitals had an average annual surgical volume of <36 cases for pancreaticoduodenectomy, 10 hospitals had an average annual surgical volume of 36-119 cases, and 3 hospitals had an average annual surgical volume of ≥120 cases. There were 2 584 cases performed pancreaticoduodenectomy in thirteen hospitals with an average annual surgical volume of ≥36 cases, accounting for 89.536%(2 584/2 886)of the total cases. There were 1 357 cases performed pancrea-ticoduodenectomy in three hospitals with an average annual surgical volume of ≥120 cases, accounting for 47.020%(1 357/2 886) of the total cases. (2) Intraoperative and postoperative conditions. Of the 2 886 patients, the surgical approach was open surgery in 2 397 cases, minimally invasive surgery in 488 cases, and it is unknown in 1 case. The pylorus was preserved in 871 cases, not preserved in 1 952 cases, and it is unknown in 63 cases. Combined organ resection was performed in 305 cases (including vascular resection in 209 cases), not combined organ resection in 2 579 cases, and it is unknown in 2 cases. The operation time of 2 885 patients was 290(115)minutes, the volume of intra-operative blood loss of 2 882 patients was 240(250)mL, and the intraoperative blood transfusion rate of 2 880 patients was 27.153%(782/2 880). Of the 2 886 patients, the invasive treatment rate was 11.342%(327/2 883), the unplanned Intensive Care Unit (ICU) treatment rate was 3.087%(89/2 883), the reoperation rate was 1.590%(45/2 830), the duration of postoperative hospital stay was 17(11)days, the hospitalization mortality rate was 0.798%(23/2 882), and the failure rate of rescue data in 2 083 cases with severe complications was 6.529%(19/291). There were 2 477 patients receiving postoperative 90-day follow-up, with the 90-day mortality of 2.705%(67/2477). The total incidence rate of complication in 2 886 patients was 58.997%(1 423/2 412). The incidence rate of severe complication was 13.970%(291/2 083). The comprehensive complication index was 8.7(22.6) in 2 078 patients. (3) Influencing factors for 90-day mortality after pancreaticoduodenectomy. Results of multivariate analysis showed that age ≥ 70 years, postoperative invasive treatment, and unplanned ICU treatment were independent risk factors for 90-day mortality after pancreaticoduodenectomy ( odds ratio=2.403, 2.609, 16.141, 95% confidence interval as 1.281-4.510, 1.298-5.244, 7.119-36.596, P<0.05). Average annual surgical volume ≥36 cases in the hospital was an independent protective factor for 90-day mortality after pancreaticoduodenectomy ( odds ratio=0.368, 95% confidence interval as 0.168-0.808, P<0.05). Conclusions:Pancreaticoduodenectomy in Jiangsu Province is highly con-centrated in some hospitals, with a high incidence of postoperative complications, and the risk of postoperative 90-day mortality is significant higher than that of hospitallization mortality. Age ≥ 70 years, postoperative invasive treatment, and unplanned ICU treatment are independent risk factors for 90-day motality after pancreaticoduodenectomy, and average annual surgical volume ≥36 cases in the hospital is an independent protective factor.

Objective To explore the role and underlying mechanism of type Ⅲ secretion system(T3SS)in regulating the internalization of Pseudomonas aeruginosa(PA)into pulmonary epithelial cells.Methods The human non-small cell lung cancer A549 cells were infected with or without PA strains,including wild-type PAO1(a standard experimental PA strain),△exsA(knockout of the critical activator for T3SS genes),△pscJ(T3SS secretion-defective strain)and PAO1-E(EGTA-induced high expression of T3SS genes).The A549 cells pretreated with ERK inhibitor U0126 or reactive oxygen species(ROS)inhibitor apocynin(APO)/N-acetyl-L-cysteine(NAC)were infected with PAO1 or PAO1-E strain.Thus,the experiment was grouped as follows:the mock-treated group,PAO1-or PAO1-E-infected group,inhibitor-treated group,and PAO1/PAO1-E plus inhibitor-treated group.Extracellular bacteria were killed by gentamicin,and the cell lysates were diluted and then plated on PA screening plates.Bacterial amounts were detected by counting colony-forming units(CFUs).The production of ROS was analyzed using fluorescent probe labeling and flow cytometry.The activation of the ERK pathway was detected by Western blotting.Results Compared with the PAO1-infected group,the intracellular bacteria and ROS level in △exsA-or△pscJ-infected cells were lower(P＜0.05,P＜0.01),so was the generation of ROS(P＜0.01);In contrast,those of the PAO1-E strain-infected cells displayed an opposite trend(P＜0.01).Compared with the PAO1-or PAO1-E-infected group,the cells pretreated with APO/NAC followed by PAO1 or PAO1-E infection showed reduced intracellular bacterial amounts(P＜0.01).Compared to the PAO1-infected A549 cells,the phosphorylation level of ERK was increased in the △exsA-or △pscJ-infected cells(P＜0.01),while that level was suppressed in the PAO1-E-treated cells(P＜0.01).Compared with the PAO1-infected group,the PAO1-infected cells pretreated with U0126 displayed reduced ERK activation,elevated ROS production,and increased intracellular counts of PAO1(P＜0.01).Conclusion T3SS-mediated inhibition of the ERK pathway promotes the production of ROS and the internalization of PA in lung epithelial cells.