Objective This study aims to achieve high-yield functional expression of the human voltage-gated potassium channel K_V3.1 using an Escherichia coli cell-free protein synthesis system, thereby providing a novel synthetic approach for drug screening, structural analysis and functional characterization of K_V3.1. Methods K_V3.1 was expressed in an Escherichia coli cell-free protein synthesis system for 10 hours in the presence of peptide surfactant A₆K. The secondary structure of K_V3.1 was analyzed by circular dichroism spectroscopy. The potassium channel activity of the recombinant protein liposome K_V3.1-A₆K was investigated using fluorescent dyes Oxonol VI as indicators, which are capable of reflecting alterations in membrane potential. Results Soluble K_V3.1 protein was successfully synthesized, achieving a purified yield of up to 1.2 mg/mL via an Escherichia coli cell-free protein synthesis system. Circular dichroism spectroscopy revealed that K_V3.1 exhibited characteristic α-helical secondary structures. Membrane potential fluorescence assays demonstrated that the K_V3.1-A₆K proteoliposomes, which were reconstructed with surfactant peptide A₆K, exhibited remarkable potassium ion permeability. Conclusion This study successfully achieved high-yield expression of human K_V3.1 with activity using an Escherichia coli-based cell-free protein synthesis system. This innovative method not only significantly enhances the expression yield of K_V3.1, but also maintains its functional activity, thereby establishing a novel and efficient synthetic platform for drug screening and advancing our understanding of structure-function relationships in K_V3.1 research.
Humans ; Escherichia coli/metabolism* ; Shaw Potassium Channels/biosynthesis* ; Cell-Free System ; Circular Dichroism ; Protein Biosynthesis ; Recombinant Proteins/metabolism* ; Membrane Potentials ; Shab Potassium Channels

Background and purpose:Tumor-associated macrophages(TAM)as the main stromal cells in the tumor microenvironment play an important role in tumor progression.This study aimed to explore the clinical significance of M1 type TAM infiltration in hepatocellular carcinoma(HCC).Methods:We collected tissue paraffin samples from 320 HCC patients who underwent surgery at the Affiliated Nantong Hospital Three of Nantong University from January 2012 to December 2020.Immunohistochemical methods were used to detect the distribution of CD86 labeled M1 type TAM in HCC tissues,and positive cell density was calculated.Groups were established according to cell density,high-density group had cells with greater than average density(29 cells/mm2),and low-density group had cells with less than or equal to average density.The correlation and prognostic significance of M1 TAM density with clinicopathologic features and tumor infiltrating CD8+T lymphocytes of HCC were analyzed.Using immunohistochemistry to detect the expression of programmed death ligand-1(PD-L1),the cases were divided into four groups based on the cell density of CD86 and PD-L1.In the CD86+high-density group,PD-L1 high-density(CD86highPD-L1high)and PD-L1 low-density(CD86highPD-L1low)groups were included.In the CD86+low-density group,the PD-L1 high-density(CD86lowPD-L1high)and PD-L1 low-density(CD86lowPD-L1low)groups were included.We analyzed the prognostic significance of CD86+M1 type TAM density combined with PD-L1 expression.This study was approved by the Ethics Committee of Affiliated Nantong Hospital Three of Nantong University(ethics number:EK2022005).Results:CD86+M1 type TAM was mainly distributed in the tumor stroma.Its high-density rate was 44.7%(143/320).The density of CD86+M1 type TAM was positively correlated with tumor infiltrating CD8+T lymphocyte density(P＜0.001)and negatively correlated with hepatitis B virus surface antigen(HBsAg)positivity(P=0.003),and had no significant correlation with clinical and pathological features such as patient age,gender,cirrhosis,tumor size,histological grading and microvascular invasion.The CD86+M1 type TAM high-density group had better overall survival(OS)and disease-free survival(DFS)than the low-density group,and the differences were statistically significant(all P＜0.001).Multivariate Cox proportional hazards regression model analysis showed that low-density CD86+M1 type TAM was an independent risk factor for evaluating OS and DFS(OS:HR=1.468,P=0.022;DFS:HR=2.233,P＜0.001).The CD86highPD-L1high group had poor OS and DFS than the CD86highPD-L1low group,and the differences were statistically significant(both P＜0.05).The CD86lowPD-L1high group had poor OS and DFS than the CD86lowPD-L1low group.The difference in OS between the two groups was statistically significant(P＜0.05),while the difference in DFS was not statistically significant.Conclusion:The presence of high-density CD86+M1 type TAM in HCC tissue suggests a good prognosis and is an independent prognostic factor.Expression of PD-L1 in HCC tissue suggests increased invasiveness and poorer prognosis.

Adjacent segment disease(ASD) refers to the degeneration of adjacent segments after lumbar fusion surgery, including intervertebral disc herniation, stress vertebral fractures, slippage, segmental scoliosis, spinal canal stenosis, and facet joint degeneration, which can lead to corresponding clinical symptoms such as lumbosacral pain, root lower limb pain, or intermittent claudication. The treatment of different pathological types of ASD varies. The patients with mild symptoms require conservative treatment and patients with severe symptoms require surgical treatment. In the past, open fusion surgery with posterior approach or intervertebral foramen approach was commonly used for surgical treatment, which had definite therapeutic effects. However, there were drawbacks such as large surgical trauma, excessive intraoperative blood loss, and slow postoperative recovery. With the booming development of minimally invasive spinal surgery technology in recent years, spinal surgeons actively use minimally invasive surgery for the treatment of ASD. It has advantages such as less bleeding, short hospital stay, fast recovery, and fewer complications (such as deep vein thrombosis and pulmonary embolism), but its indications are limited. Therefore, this article provides a reference for the choice of ASD treatment by reviewing the treatment modalities of ASD with different pathological types.

Objective To construct recombinant human butyrylcholinesterase(rhBChE)knock-in goat fetal fibroblast cell lines(GFFs)by using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-mediated homology-directed repair mechanism for subsequent production of goat expressing rhBChE.Methods The efficient sgRNA sites targeting goat[3-casein(CSN2)gene were designed and screened,and the targeting efficiency of the sgRNA in goat mammary epithelial cells(GMECs)was confirmed by electro-transfection,flow sorting,and sequencing of PCR products.The red fluorescent reporter gene homology repair vector(P2A-mCherry)targeting the sgRNA was constructed,and then the integration and expression efficiency was detected by flow cytometry.The rhBChE homology repair vector(P2A-rhBChE)targeting the sgRNA of CSN2 gene was constructed in GFFs,the rhBChE positive cell clones were obtained via electro-transfection and flow sorting,and the rhBChE knock-in cell lines was identified by sequencing of PCR products.Results The sgRNA4 was identified as an efficient target of goat CSN2 gene,which could be also used for targeted integration of other genes.Three rhBChE knock-in cell lines were successfully constructed.Conclusion The rhBChE knock-in GFFs targeting goat CSN2 gene lays the foundation for the production of mammary bioreactors expressing rhBChE.

Objective: To explore the effects of different concentrations of glucose solution on the survival of Aedes albopictus and Culex pipiens pallens larvae, the attraction to mosquitoes and egg-laying behaviors, so as to provide the reference for developing mosquito control technology based on sugar bait. Methods: White porcelain bowls were filled with 100 mL of 3%, 5%, 8%, 10% and 15% glucose solutions. Ten of fourth instar larvae of Aedes albopictus or Culex pipiens pallens were added to each bowl, and the survival of larvae was recorded after 2, 4, 6, 24, 48 and 72 hours. Egg-laying cups containing 5%, 8% and 15% glucose solution were put in mosquito cages containing fully blooded female mosquitoes of Aedes albopictus and Culex pipiens pallens (50 mosquitoes each), and the total number of eggs laid in 72 hours was observed. The analogous site room was filled with fully blooded and starved female mosquitoes of Aedes albopictus and Culex pipiens pallens (100 mosquitoes each), and simple mosquito control buckets containing 5% and 8% glucose solution and black sticky insect plates. The number of mosquitoes and eggs was observed after 6 days. All the above experiments were repeated 3 times using dechlorinated water as the control. Results: The 72 hour corrected mortality rates of Aedes albopictus and Culex pipiens pallens larvae gradually increased with the increase of glucose concentration. The glucose solution with 5% and higher concentrations was not suitable for mosquito larvae to survive. The attraction of egg-laying behaviors to Aedes albopictus and Culex pipiens pallens gradually decreased with the increase of glucose concentration. The effects were similar between 5% and 8% glucose solution, with the averages of 686.67 and 682.33 eggs for Aedes albopictus, and 3.00 and 2.33 egg rafts for Culex pipiens pallens. In analogous site room, there were 93.33, 105.00 and 130.33 adult mosquitoes captured on average in the control group, 5% and 8% glucose solution groups, respectively, with 8% glucose solution group more attractive to adult mosquitoes than the control group (F=3.283, P=0.030); there were 70.33, 55.33 and 63.00 Aedes albopictus eggs (eggs counts+larvae counts) on average, respectively, with statistically significant differences among the three groups (H=6.761, P=0.034). Conclusion Glucose solution with concentration of 5% or higher can effectively inhibit the survival of Aedes albopictus and Culex pipiens pallens larvae, and attractive to adult mosquitoes and egg-laying behavoirs.

AIM:To explore the effects of CD38 on lysosome reformation and cholesterol efflux in macro-phages.METHODS:Bone marrow-derived macrophages from low-density lipoprotein(LDL)receptor knockout(LDLr-/-)mice were cultured as cell model.Live cell imaging system was applied to evaluate the effect of nicotinic acid adenine di-nucleotide phosphate(NAADP)on lysosome number.ELISA was conducted to measure NAADP level in macrophages.After the cells were treated with nicotinic acid(NA),RT-qPCR was conducted to detect CD38 mRNA expression,and Western blot was conducted to observe CD38 protein expression and phosphorylated transcription factor EB(TFEB)level.Laser scanning confocal microscopy was applied to evaluate the influence of CD38/NAADP signaling on lysosome number and cholesterol egression.RESULTS:NAADP remarkably increased lysosome number(P<0.05),and this effect was significantly inhibited by NAADP antagonist NED-19,Ca2+ chelator BAPTA,and calcineurin inhibitor CsA(P<0.05).CD38 markedly enhanced NAADP synthesis in macrophages(P<0.05).NAADP synthetic substrate NA prominently ele-vated the expression of CD38 mRNA and protein(P<0.05).NA significantly decreased the phosphorylated TFEB level;this effect was also attenuated by NED-19,BAPTA and CsA(P<0.05).Disrupting CD38/NAADP signaling pathway markedly inhibited NA-induced enhancement of lysosome number,lysosomal free cholesterol and cytosol cholesterol ester efflux in macrophages(P<0.05).NA-induced enhancement of lysosome number,lysosomal free cholesterol and cytosol cholesterol ester efflux abolished in LDLr/CD38 DKO macrophages(P<0.05),whereas these effects induced by NA were recovered after CD38 gene rescue.CONCLUSION:CD38 triggers lysosome reformation via TFEB and consequently pro-motes the efflux of lysosomal free cholesterol and cytosol cholesterol ester.

The ultrasonic manifestations of benign and malignant breast imaging-reporting and data system(BI-RADS)4 lesions overlap in some degrees,is able to result in unnecessary biopsy or untimely therapy.Accurate classifying the nature of BI-RADS 4 breast lesions can provide reliable references for clinical decision-making.The progresses of application of new ultrasonic technologies,including automated breast volume scanner,superb micro-vascular imaging,elastography,contrast-enhanced ultrasound and artificial intelligence for assisting diagnosis of BI-RADS 4 lesions were reviewed in this article.

ObjectiveTo observe the effect of augmented reality training based on enriched environment on walking dysfunction after stroke. MethodsFrom January, 2021 to June, 2022, 36 stroke patients in the Affiliated Suzhou Hospital of Nanjing University Medical School were randomly divided into control group (n = 18) and experimental group (n = 18). Both groups received conventional rehabilitation treatment. The control group was supplemented with conventional walking training, and the experimental group was supplemented with augmented reality training based on enriched environment, for four weeks. They were assessed with Berg Balance Scale (BBS), Timed Up and Go Test (TUGT), 10-meter walk test (10MWT) and Barthel Index (BI) before and after treatment, and the gait parameter was compared. ResultsNo adverse event occurred during treatment. After treatment, the BBS score, TUGT time, 10MWT speed, BI, gait speed, gait frequency and the proportion of single-leg support on the affected side significantly improved in both groups (|t| > 5.161, P < 0.001). All the above indexes were better in the experimental group than in the control group (|t| > 2.106, P < 0.05), except for BI (t = 1.099, P = 0.282). ConclusionAugmented reality training based on enriched environment could improve the walking function of paitents after stroke, which is better than conventional walking training.

BACKGROUND: Standard two-dimensional (2D) culture has confirmed the mechanism of mast cells (MCs) in the pathogenesis of inflammatory bowel disease (IBD), but the regulation of signaling responses of MCs may well differ in three-dimensional (3D) microenvironments. The aim of the study was to develop a 3D culture model based on decellularized intestinal scaffolds (DIS) and verify how MCs influenced fibroblasts phenotype in the 3D model. METHODS: DIS were achieved using the detergent technique and extracellular matrix (ECM) components were verified by histologic analysis, quantification and scanning electron microscope. After human colon fibroblasts recellularized into the scaffolds and activated by MCs tryptase and TGFb1, the changes in genes and signaling pathways during fibroblasts activation in 3D were studied and compared with the changes in 2D cell culture on plastic plates. RESULTS: Decellularization process effectively removed native cell debris while retaining natural ECM components and structure. The engrafted fibroblasts could penetrate into the scaffolds and maintain its phenotype. No matter whether fibroblasts were cultured in 2D or 3D, MCs tryptase and transforming growth factor b1 (TGF-b1) could promote the differentiation of fibroblasts into fibrotic-phenotype myofibroblasts through Akt and Smad2/3 signaling pathways. Furthermore, the pro-collagen1a1 and fibronectin synthesis of myofibroblasts in 3D was higher than in 2D culture. CONCLUSION Our results demonstrated that the DIS can be used as a bioactive microenvironment for the study of intestinal fibrosis, providing an innovative platform for future intestinal disease modeling and screening of genes and signaling pathways.

Objective:To explore the effect of shoulder subluxation on the peripheral nerves in the hemiplegic upper limbs of stroke survivors.Methods:Twenty stroke survivors with shoulder subluxation were enrolled. Conduction in their suprascapular, axillary, musculocutaneous, radial, median and ulnar nerves was monitored and needle electromyography was used to monitor activity in the supraspinatus, deltoid, biceps brachii, extensor digitorum, abductor pollicis brevis and abductor digiti minimi muscles of their affected upper limbs at rest. Upper limb and hand function were assessed using the Brunnstrom scale. The rate of change in the amplitude of the compound muscle action potentials (CMAPs) was correlated with the patient′s disease duration, age, and upper limb and hand Brunnstrom stages.Results:Compared with the healthy side, a significant decrease was observed in the CMAP amplitudes of the suprascapular, axillary, musculocutaneous, radial, median and ulnar nerves of the hemiplegic arm, and the latency of the suprascapular and axillary nerves was significantly prolonged. There was no inter-arm difference in the conduction velocity of the musculocutaneous, radial, median and ulnar nerves. The rates of change in the CMAP amplitudes of the suprascapular, axillary and musculocutaneous nerves were significantly higher than those of the radial, median and ulnar nerves. The sensory nerve action potential (SNAP) amplitudes of the median, ulnar and radial nerves on the hemiplegic side were significantly lower than on the healthy side, but there was no significant difference in the sensory conduction velocity between the two sides. On the hemiplegic side, the median nerve had the highest rate of change rate in the SNAP amplitude, followed by the radial and ulnar nerves, but there was no significant difference among them. Nor was there any significant difference in the rate of change in sensory nerve conduction velocity. The muscles of the affected upper limbs had higher potentials in the proximal than that in the distal nerves after shoulder subluxation. The rate of change in the CMAPs was not significantly correlated with a patient′s disease duration, age, or upper limb or hand Brunnstrom stage on the hemiplegic side.Conclusions:Shoulder subluxation after a stroke can cause greater damage to the peripheral nerves in the shoulder and upper arm than to those in the forearm and hand, possibly affecting the recovery of upper limb function.