Melatonin (Mel) has been shown to have cardioprotective effects, but its action on ion channels is unclear. In this experiment, we investigated the inhibitory effect of Mel on late sodium currents (I_Na.L) in mouse ventricular myocytes and the anti-arrhythmic effect at the organ level as well as its mechanism. The whole-cell patch clamp technique was applied to record the ionic currents and action potential (AP) in mouse ventricular myocytes while the electrocardiogram (ECG) and monophasic action potential (MAP) were recorded simultaneously in mouse hearts using a multichannel acquisition and analysis system. The results demonstrated that the half maximal inhibitory concentration (IC₅₀) values of Mel on transient sodium current (I_Na.T) and specific I_Na.L opener 2 nmol·L^-1 sea anemone toxins II (ATX II) increased I_Na.L were 686.615 and 7.37 μmol·L^-1, respectively. Mel did not affect L-type calcium current (I_Ca.L), transient outward current (I_to), and AP. In addition, 16 μmol·L^-1 Mel shortened ATX II-prolonged action potential duration (APD), suppressed ATX II-induced early afterdepolarizations (EADs), and significantly reduced the incidence of ventricular tachycardia (VT) and ventricular fibrillation (VF) in Langendorff-perfused mouse hearts. In conclusion, Mel exerted its antiarrhythmic effects principally by blocking I_Na.L, thus providing a significant theoretical basis for new clinical applications of Mel. Animal welfare and experimental process are in accordance with the regulations of the Experimental Animal Ethics Committee of Wuhan University of Science and Technology (2023130).

Objective To investigate the predictive value of new simplified insulin resistance(IR)assessment indexes in identifying subclinical left ventricular systolic function impairment in patients with type 2 diabetes mellitus(T2DM).Methods A total of 150 T2DM patients with preserved left ventricular ejection fraction(LVEF≥50%)who were admitted to Department of Endocrinology of the First Affiliated Hospital of Air Force Medical University from June 2021 to December 2021 were retrospectively analyzed.All patients underwent two-dimensional speckle tracking echocardiography to measure left ventricular global longitudinal strain(GLS).According to GLS value,the subjects were divided into the normal group(GLS≥18%group,n=80)and the impaired group(GLS<18%group,n=70).Some new simplified IR assessment indicators were calculated and compared between the two groups,including body mass index(BMI),TG/HDL-C ratio,triglyceride-glucose(TyG)index,TyG-BMI index,TyG-WHR and metabolic score for IR(METS-IR).Correlation between the GLS and the new simplified IR assessment indexes was analyzed.The receiver operating characteristic(ROC)curve was used to analyze the diagnostic efficacy of different simplified IR assessment indexes,with the area under the curve(AUC)calculated.Furthermore,according to whether the subjects were complicated with hypertension,binary logistics regression analysis was performed to explore the independent correlation between the simplified IR assessment index and GLS<18%.Results Total 150 were included with aged(54.5±13.7)years with 96(64.0%)men and 54(36.0%)women.Compared with the GLS≥18%group,the TG/HDL-C ratio,TyG index,TyG-BMI,and METS-IR of subjects in the GLS<18%group were significantly increased(P<0.05).Pearson correlation analysis showed that TG/HDL-C ratio,TyG index,TyG-BMI,TyG-WHR,and METS-IR were negatively correlated with GLS(P<0.05).ROC analysis showed that TyG index had a certain predictive value for the evaluation of GLS<18%(AUC=0.678,95%CI 0.591-0.765,P<0.001).Stratification based on hypertension and further adjusting for confounding factors,TyG index remains significantly associated with GLS<18%(OR=3.249,95%CI 1.045-10.103,P=0.042).Conclusions The novel simplified insulin resistance evaluation indexes are closely associated with left ventricular subclinical systolic dysfunction in T2DM patients with preserved ejection fraction.TyG index is an effective index to identify left ventricular subclinical dysfunction in these populations.

Objective To explore the relevant factors of new-onset conduction disturbance(NOCD)after transcatheter aortic valve replacement(TAVR),such as anatomical structure,device type,surgical strategies,etc.,discover relevant predictive factors,and establish a predictive model to assess the risk of conduction blockages.Methods From January 2016 to March 2022,clinical data of symptomatic patients with severe aortic valve stenosis or severe regurgitation who underwent TAVR at Xiangya Second Hospital of Central South University were collected through the hospital information system and imaging database.ECG,echocardiography,CTA,surgical materials,etc.,were extracted and analyzed by specialists.SPSS software was used for statistical analysis,and a multi-factor regression prediction model for NOCDwas built.Results A total of 184 patients were included,the occurrence rate of NOCD after TAVR was 31.0%,pure regurgitation patients'NOCD occurrence rate was 63.6%(7/11).The NOCD group had a larger aortic angles[(57.7±10.3)°vs.(52.0±9.0)°,P＜0.001],larger Oversizing[(129±28)%vs.(120±21)%,P=0.018],deeper implantation depth[(7.2±5.1)mm vs.(4.8±4.2)mm,P=0.001],and higher pure regurgitation patients'proportion[12.3%vs.3.1%,P=0.037]than the non-NOCD group.Multifactorial Logistic regression analysis indicated that an aorta angle＞54.5°(OR 3.78,95%CI 1.86-7.63,P＜0.001)or implantation depth＞5.7 mm(OR 3.39,95%CI 1.68-6.85,P＜0.001)are independent risk factors for new onset conduction disturbances after TAVR,and a predictive model was established with aortic angle,implantation depth,and Oversizing ratio as variables.The receiver operating characteristics curve showed area under ROC curve 0.709,95%CI 0.623-0.795,predicting NOCD after TAVR.Conclusions A retrospective analysis carried out at a single center discovered that the aortic angle in the NOCD group was larger than that in the non-NOCD group,the Oversizing ratio was higher,the implantation location was deeper,and there was a higher proportion of patients with pure regurgitation lesions.An aortic angle greater than 54.5°or an implantation depth more than 5.7 mm were identified as independent risk factors for NOCD after TAVR.

Tuberous sclerosis complex(TSC)is a rare genetic disease that can lead to benign dysplasia in multiple organs such as the skin, brain, eyes, oral cavity, heart, lungs, kidneys, liver, and bones. Its main symptoms include epilepsy, intellectual disabilities, skin depigmentation, and facial angiofibromas, whilst incidence is approximately 1 in 10 000 to 1 in 6000 newborns. This case presents a middle-aged woman who initially manifested with epilepsy and nodular depigmentation. Later, she developed a lower abdominal mass, elevated creatinine, and severe anemia. Based on clinical features and whole exome sequencing, the primary diagnosis was confirmed as TSC. Laboratory and imaging examinations revealed that the lower abdominal mass originated from the uterus. CT-guided biopsy pathology and surgical pathology suggested a combination of leiomyoma and abscess. With the involvement of multiple organs and various complications beyond the main diagnosis, the diagnostic and therapeutic process for this patient highlights the importance of rigorous clinical thinking and multidisciplinary collaboration in the diagnosis and treatment of rare and challenging diseases.

Bacterial biofilms gave rise to persistent infections and multi-organ failure, thereby posing a serious threat to human health. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure, high adhesiveness and low drug permeability, and had been found in many human organs or tissues, such as the brain, heart, liver, spleen, lungs, kidneys, gastrointestinal tract, and skeleton. By releasing pro-inflammatory bacterial metabolites including endotoxins, exotoxins and interleukin, biofilms stimulated the body’s immune system to secrete inflammatory factors. These factors triggered local inflammation and chronic infections. Those were the key reason for the failure of traditional clinical drug therapy for infectious diseases.In order to cope with the increasingly severe drug-resistant infections, it was urgent to develop new therapeutic strategies for bacterial-biofilm eradication and anti-bacterial infections. Based on the nanoscale structure and biocompatible activity, nanobiomaterials had the advantages of specific targeting, intelligent delivery, high drug loading and low toxicity, which could realize efficient intervention and precise treatment of drug-resistant bacterial biofilms. This paper highlighted multiple strategies of biofilms eradication based on nanobiomaterials. For example, nanobiomaterials combined with EPS degrading enzymes could be used for targeted hydrolysis of bacterial biofilms, and effectively increased the drug enrichment within biofilms. By loading quorum sensing inhibitors, nanotechnology was also an effective strategy for eradicating bacterial biofilms and recovering the infectious symptoms. Nanobiomaterials could intervene the bacterial metabolism and break the bacterial survival homeostasis by blocking the uptake of nutrients. Moreover, energy-driven micro-nano robotics had shown excellent performance in active delivery and biofilm eradication. Micro-nano robots could penetrate physiological barriers by exogenous or endogenous driving modes such as by biological or chemical methods, ultrasound, and magnetic field, and deliver drugs to the infection sites accurately. Achieving this using conventional drugs was difficult. Overall, the paper described the biological properties and drug-resistant molecular mechanisms of bacterial biofilms, and highlighted therapeutic strategies from different perspectives by nanobiomaterials, such as dispersing bacterial mature biofilms, blocking quorum sensing, inhibiting bacterial metabolism, and energy driving penetration. In addition, we presented the key challenges still faced by nanobiomaterials in combating bacterial biofilm infections. Firstly, the dense structure of EPS caused biofilms spatial heterogeneity and metabolic heterogeneity, which created exacting requirements for the design, construction and preparation process of nanobiomaterials. Secondly, biofilm disruption carried the risk of spread and infection the pathogenic bacteria, which might lead to other infections. Finally, we emphasized the role of nanobiomaterials in the development trends and translational prospects in biofilm treatment.

ObjectiveThe scale of microalgae farming industry is huge. During farming, it is easy for microalgae to be affected by miscellaneous bacteria and other contaminants. Because of that, periodic test is necessary to ensure the growth of microalgae. Present microscopy imaging and spectral analysis methods have higher requirements for experiment personnel, equipment and sites, for which it is unable to achieve real-time portable detection. For the purpose of real-time portable microalgae detection, a real-time microalgae detection system of low detection requirement and fast detection speed is needed. MethodsThis study has developed a microalgae detection system based on deep learning. A microscopy imaging device based on bright field was constructed. With imaged captured from the device, a neural network based on YOLOv3 was trained and deployed on microcomputer, thus realizing real-time portable microalgae detection. This study has also improved the feature extraction network by introducing cross-region residual connection and attention mechanism and replacing optimizer with Adam optimizer using multistage and multimethod strategy. ResultsWith cross-region residual connection, the mAP value reached 0.92. Compared with manual result, the detection error was 2.47%. ConclusionThe system could achieve real-time portable microalgae detection and provide relatively accurate detection result, so it can be applied to periodic test in microalgae farming.

Objective To apply a COMSOL-based finite element analysis method to investigating the electric field effects produced by the human lower limb musculoskeletal system under the synergistic effects of stress field and electromagnetic field.Methods Firstly,a 3D human body model was constructed by Maxon Cinema 4D R21 software,and then imported into COMSOL 6.1 software in STL format.Secondly,an electromagnetic field intervention and stress loading model for the left lower limb of the human body was designed and constructed,in which 15 Hz quasi-pulse group current signals were used for electromagnetic field excitation and the stress field was realized by applying a vibration load with an average compressive force of about 90 N/cm2 to the left foot of the human body.Finally,the electromagnetic properties of human tissue were simulated by numerical simulation,and then the effects of stress field or elecromagnetic field or combined stress field and electromagnetic field on human bioelectric field were compared.Results Simulation results showed that the electric field intensity peaked at the leg joints under both electromagnetic and stress fields acting alone or synergistically,the bioelectric field intensity generated by the human body was related to the distance from the exogenous excitation loading location,and the electric field generated under synergistic action was equivalent to the linear superposition of the bioelectric field in the tissue induced by the electromagnetic field and the stress field acting alone.Conclusion Data supplement is provided for predicting bioelectric field changes within the musculoskeletal tissue,and theoretical foundation is laid for the development and application of multi-physics field synergistic intervention therapy for treating the disorders of the lower limb musculos-keletal system.[Chinese Medical Equipment Journal,2024,45(9):21-26]

Objective To investigate the value of 18F labeled prostate-specific membrane antigen(18F-PSMA)-1007 developing agent PET/CT(18F-PSMA-1007PET/CT)examination in the diagnostic evaluation and therapeutic decision of the newly diagnosed prostate cancer(PCa)and follow up after radical prostatecto-my(RP).Methods This study adopted the retrospective observational study method.A total of 68 patients receiving 18 F-PSMA-1007 PET/CT examination in this hospital from September 2022 to October 2023 were analyzed,including 36 cases of newly diagnosed PCa and 32 cases of biochemistry follow up failure after RP.A total of 30 items of clinical data were collected,including 8 items of basic clinical characteristics,7 items of pa-thology-related characteristics and 15 items of imaging characteristics.The patients clinical characteristics in the newly diagnosed PCa and biochemical failure after RP conducted the descriptive analysis.The Fisher exact probability method was used to analyze the differentiation of the SUVmax of primary lesions in different clini-cal subgroups[different tPSA levels at diagnosis,different mi-T stages,different Gleason scores at postopera-tive pathological puncture and different pathological types]in the newly diagnosed PCa group and the differ-entiation of recurrent lesion detection rates in different clinical subgroups(different tPSA in 18F-PSMA-1007 PET/CT examination,different pathological T stages,different lymph node invasion and different pathological Gleason scores in the biochemical failure after RP group.The Spearman correlation was adopted to test and analyze the correlation between the imaging features of positive lesions and tPSA.Results In the newly diag-nosed PCa group,there were 1 case of prostatic hyperplasia and 35 cases of PCa.SUVmax had no statistical differences among the primary lesions with different tPSA levels(P=0.81),different mi-T stages(P=0.70),different puncture Glleasonscores(P=0.20)and different pathological types(P=0.71).Moreover the tPSA value at diagnosis was positively correlated with the number of metastatic lesions(r=0.410,P=0.01).The clinical treatment decisions in 11 cases(31.43％)were changed according to the examination re-sults.In 9 cases of RP combined with lymph node dissection,the accuracy rate and concordance rate of 18F-PS-MA-1007 PET/CT and MRI in the lymph node detection rate all were 100％.I n the biochemical failure after RP group,the overall recurrent lesion detection rate was 71.88％(23/32),the operative area in situ recurrence(11 cases,34.38％)and bone metastasis(11 cases,34.38％)were most common.The differences of 18F-PS-MA-1007 PET/CT recurrent lesions detection rates had no statistical differences among the patients with dif-ferent tPSA levels(P=0.08),different pathological T stages(P=0.10),different postoperative pathological lymph node invasions(P=0.68)and different pathologic Gleason score in the 18F-PSMA-1007 PET/CT ex-amination.In the 18 F-PSMA-1007 PET/CT examination in the biochemical failure after RP,the tPSA value in the recurrent lesion was positively correlated with the number of recurrent lesions(r=0.48,P=0.01),SUVmax value in the recurrent lesion(r=0.46,P=0.01)and the SUVmean value(r=0.38,P=0.03).The clinical treatment decision in 18 cases(56.25％)was changed according to the examination results.Conclusion 18 F-PSMA-1007 PET/CT has good diagnostic value and efficiency for primary lesion and metastasis lesion of new-ly diagnosed PCa and recurrent foci of biochemical failure after RP.

Objective:To summarize the best evidence on case management of patients with home enteral nutrition.Methods:Relevant evidence on the case management of home enteral nutrition patients was retrieved by literature search,and the evidence was extracted and summarized for the literature that met the quality requirements.Result:A total of 10 literatures were included,including 1 guideline,3 expert consensus,2 industry standards,1 systematic review and 3 randomized controlled trials.By establishment of archives,policy management,establishment of multidisciplinary teams,overall evaluation of home enteral nutrition,as well as implementation management,a total of 33 home enteral nutrition case management was summarized from 6 aspects including health education and follow-up,etc.Conclusion:All the summarized relevant evidence about case filing and management of home enteral nutrition patients can be applied in clinical practice to promote the standardized management of home enteral nutrition.

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates.Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity.This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes.The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes,and corresponding reference ranges will be established.The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance,with altitude gradients divided into 4 categories:800 m,1 900 m,2 400 m,and 3 500 m,with an anticipated sample size of 170 neonates per altitude gradient.This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.[Chinese Journal of Contemporary Pediatrics,2024,26(4):403-409]