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.

Lung adenocarcinoma (LUAD) is a global malignancy with significant chemoresistance impacting patient prognosis. The pro-tumorigenic role of hyaluronan-mediated motility receptor (HMMR) in LUAD is recognized. This study was designed to investigate the underlying mechanisms by which HMMR affects chemoresistance in LUAD. Bioinformatics presented the expression patterns of HMMR in LUAD patients and the association between HMMR levels and patient survival, followed by qRT-PCR to verify HMMR expression in LUAD tissues and cells. Further, bioinformatics was leveraged to identify the signaling pathways enriched by HMMR and its relevance to glycolytic genes, we also analyzed changes in the glycolytic activity of LUAD cells by manipulating HMMR expression. Stemness was evaluated through cell aggregation assays and Western blot, and drug responsiveness was gauged using CCK-8 assays, alongside flow cytometry for apoptosis analysis. HMMR was highly expressed in LUAD tissues and cells, and this overexpression correlated with poorer prognoses in patients. GSEA showed that HMMR was notably enriched in the glycolysis and gluconeogenesis pathways, correlating positively with the expression of key glycolytic genes. Cellular experiments confirmed that HMMR knockdown notably suppressed aerobic glycolysis in LUAD cells. Moreover, overexpression of HMMR could further enhance the stemness and cisplatin resistance of LUAD cells by stimulating glycolysis. In brief, this study has validated that high levels of HMMR in LUAD are predictive of poor patient prognosis, and that overexpression of HMMR can catalyze aerobic glycolysis, thus promoting stemness and chemoresistance in LUAD cells. Thus, HMMR could be a target for improving chemosensitivity in LUAD.

AIM:This study aims to investigate the synergistic cytotoxic effects of chrysin and venetoclax on acute myeloid leukemia(AML)cells and to elucidate the underlying mechanisms.METHODS:Human AML cell lines MV411 and MOLM13 were cultured in vitro and treated with chrysin in combination with venetoclax.Cell viability was as-sessed using the CCK8 assay,while flow cytometry was employed to measure cell cycle distribution and apoptosis rates.Western blot was used to detect the expression of apoptosis-related proteins and protein kinase B(PKB/Akt)/nuclear factor-κB(NF-κB)signaling pathway-related proteins.RESULTS:The results from the CCK8 assay and flow cytometry demon-strated that treatment with 16 and 32 μmol/L chrysin significantly inhibited the viability of AML cells and increased the proportion of cells in G1 phase,as well as the apoptosis rate.Notably,the cells in combination treatment group exhibited a marked reduction in proliferation and an elevated apoptosis rate compared with either chrysin or venetoclax group alone.Western blot analysis indicated that increasing concentrations of chrysin led to an elevation in cleaved poly(ADP-ribose)polymerase(PARP)level,alongside a down-regulation of proteins associated with the Akt/NF-κB signaling pathway.Fur-thermore,the combination treatment significantly up-regulated cleaved PARP level and down-regulated Akt/NF-κB path-way-related proteins compared with the treatment with chrysin or venetoclax alone.CONCLUSION:Chrysin and veneto-clax synergistically inhibit the proliferation of AML cells and promote apoptosis by modulating the Akt/NF-κB signaling pathway.

Apurinic/apyrimidinic endonuclease 1(APE 1)is a multifunctional protein that plays important roles in DNA repair and regulation of gene expression.Because APE 1 is overexpressed in various cancers,it can serve as a cancer biomarker for aiding clinical diagnosis,guiding therapy,and monitoring prognosis.On this basis,a label-free fluorescent probe was designed based on the primer exchange reaction(PER)strategy for highly sensitive detection of APE 1 activity.In the absence of APE 1,the structure of catalytic hairpin(HP)was stable and could not form G-quadruplex.Therefore,the background fluorescence of this sensing system was very low due to the dissociation of thioflavin T(ThT).In the presence of APE 1,the apurinic/apyrimidinic(AP)site of HP was cleaved by APE 1 and a short nucleic acid fragment that acted as a primer to initiate PER was generated.After PER reaction,a large number of G-quadruplex were produced,which could specifically bind with ThT and resulted in significant increase of fluorescence signal.The combination of low background design of HP and PER amplification made this biosensor had high sensitivity with a detection limit(3σ)of 0.0008 U/mL.Furthermore,the primer sequence was directly generated by the cleavage of APE 1 without additional addition,which not only increased the specificity of the reaction,but also simplified the experiment procedure.Moreover,the use of label-free fluorescence signal reduced the cost of the experiment,and realized rapid detection of APE 1.Finally,this sensor was used to detect APE 1 in human serum samples with spiked recoveries of 91%-104%,proving great potential in study of biological enzyme.

Poly(lactic-co-glycolide)(PLGA)is a key excipient in long-acting sustained-release preparations,and its degradation properties directly affect the drug release behavior.In this study,PLGA microspheres were prepared by microfluidic techniques,and the morphology changes of the microspheres were observed by scanning electron microscopy(SEM).In alkaline environment,due to the accelerated hydrolysis of ester bonds,the surface of the microspheres was rapidly dissolved and eroded,and the degradation rate was significantly higher than that in acidic environment.High temperature accelerated the degradation of PLGA microspheres.Under neutral and alkaline conditions,the microspheres showed aggregation and adhesion.Under acidic conditions,the microspheres gradually decomposed into irregular fragments.The high ionic strength further promoted the surface corrosion of the microspheres,especially under extreme pH conditions.Simultaneously,PLGA microspheres encapsulating coumarin were prepared to simulate the microsphere formulation.The release rate of coumarin after degradation of the microspheres under different conditions was observed by measuring the absorbance with ultraviolet-visible spectrophotometry.The results were consistent with those of the blank microspheres.This study revealed that the degradation of PLGA microspheres was significantly pH-dependent,temperature sensitive and ion strength responsive.These findings not only helped to understand and optimize the long-term stability and controlled release performance of drug-carrying microspheres,but also provided a theoretical basis for further improvement of PLGA-based drug carrier design.

Psoriasis is a chronic inflammatory skin disease, and its pathogenesis is largely modulated by abnormal angiogenesis. Previous research has indicated that AlkB homolog 5 (ALKBH5), an important demethylase affecting N⁶-methyladenosine (m⁶A) modification, plays a role in regulating angiogenesis in cardiovascular and eye diseases. Our present study found that ALKBH5 was upregulated and co-localized with cluster of differentiation 31 (CD31) in the skin of IMQ group compared with control group. ALKBH5-deficient mice decreased IMQ-induced psoriatic dermatitis and exhibited histological improvements, including decreased epidermal thickness, hyperkeratosis, numbers of dermal capillary vessels and inflammatory cell infiltration. ALKBH5-KO mice alleviated angiogenesis in psoriatic lesions by downregulating the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. Additionally, the expression of ALKBH5 was significantly upregulated in IL-17A-induced human umbilical vein endothelial cells (HUVECs), which further promoted the expression of angiogenesis-related cytokines and endothelial cell proliferation. Cell proliferation and angiogenesis were suppressed in ALKBH5 knockdown group, whereas ALKBH5 overexpression promoted these processes. The regulation of angiogenesis in HUVECs by ALKBH5 was facilitated through the AKT-mTOR pathway. Collectively, ALKBH5 plays a pivotal role in psoriatic dermatitis and angiogenesis, which may offer a new potential targets for treating psoriasis.
Animals ; Psoriasis/chemically induced* ; Mice ; Humans ; Neovascularization, Pathologic/genetics* ; Human Umbilical Vein Endothelial Cells/metabolism* ; AlkB Homolog 5, RNA Demethylase/genetics* ; Proto-Oncogene Proteins c-akt/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Cell Proliferation ; Mice, Knockout ; Disease Models, Animal ; Signal Transduction ; Male ; Skin/blood supply* ; Mice, Inbred C57BL ; Angiogenesis

Acute respiratory distress syndrome (ARDS) is a common respiratory emergency, but current clinical treatment remains at the level of symptomatic support and there is a lack of effective targeted treatment measures. Our previous study confirmed that inhalation of hydrogen gas can reduce the acute lung injury of ARDS, but the application of hydrogen has flammable and explosive safety concerns. Drinking hydrogen-rich liquid or inhaling hydrogen gas has been shown to play an important role in scavenging reactive oxygen species and maintaining mitochondrial quality control balance, thus improving ARDS in patients and animal models. Coral calcium hydrogenation (CCH) is a new solid molecular hydrogen carrier prepared from coral calcium (CC). Whether and how CCH affects acute lung injury in ARDS remains unstudied. In this study, we observed the therapeutic effect of CCH on lipopolysaccharide (LPS) induced acute lung injury in ARDS mice. The survival rate of mice treated with CCH and hydrogen inhalation was found to be comparable, demonstrating a significant improvement compared to the untreated ARDS model group. CCH treatment significantly reduced pulmonary hemorrhage and edema, and improved pulmonary function and local microcirculation in ARDS mice. CCH promoted mitochondrial peripheral division in the early course of ARDS by activating mitochondrial thioredoxin 2 (Trx2), improved lung mitochondrial dysfunction induced by LPS, and reduced oxidative stress damage. The results indicate that CCH is a highly efficient hydrogen-rich agent that can attenuate acute lung injury of ARDS by improving the mitochondrial function through Trx2 activation.

Lens injury is an important etiological factor in the reduction of visual function following ocular trauma.Currently, there are no clear standards for the classification of lens injury, and comprehensive diagnostic tools are lacking.This deficiency leads to numerous controversies and challenges in critical areas, such as diagnosis and preoperative evalution, timing of surgery, surgical strategy, and assessment of postoperative prognosis.Tomographic imaging technology, such as computed tomography, magnetic resonance imaging, optical coherence tomography, has introduced a new dimension to the evaluation of lens injury, which is crucial for assessing the transparency, texture, location, morphology, and integrity of the lens, as well as the zonules and nearby intraocular structures.However, the use of tomographic imaging technology is somewhat limited due to the limitations of relying on a single method.With the ongoing advancement of imaging technologies and the rapid development of big data and artificial intelligence, tomographic imaging will become an increasingly essential tool in the future management of lens injury.Our expert group reviewed the epidemiological characteristics and classification of lens injury and the major challenges currently faced in the diagnosis and treatment of lens injury, and provided expert recommendations mainly focusing on the application, shortcomings and limitations of current tomographic imaging technology in the diagnosis and treatment of lens injury, and future development directions.

Objective To investigate the effect of closed-chain exercise training on hemiplegic shoulder pain and shoulder joint sta-bility in stroke patients,and to explore the relationship between hemiplegic shoulder pain and shoulder joint sta-bility.Methods A total of 52 stroke patients with hemiplegic shoulder pain in Jiangsu Province Hospital from October,2020 to January,2023 were selected,and were randomly divided into control group(n=26)and experimental group(n=26).Both groups received conventional rehabilitation therapy,while the experimental group additionally under-went closed-chain exercise training for shoulder joint.Pain severity and motor function were assessed using Visu-al Analog Scale(VAS)and Fugl-Meyer Assessment-Upper Extremities(FMA-UE)before and after intervention.Musculoskeletal ultrasound was used to measure acromion-greater tuberosity distance(AGT),acromion-lesser tu-berosity distance(ALT),acromiohumeral distance(AHD)and supraspinatus thickness(SST)to evaluate shoulder joint stability.Correlation analysis was conducted on the improvements in shoulder pain and shoulder joint stabil-ity in the experimental group.Results Two cases in the control group and two in the experimental group dropped down.Both groups showed signifi-cant improvements in VAS and FMA-UE scores after intervention(|t|>5.214,P<0.001),and the scores im-proved more in the experimental group than in the control group(|t|>2.087,P<0.05).The experimental group also showed significant improvements in AGT,ALT,AHD and SST(|t|>4.187,P<0.001),with AGT,ALT and AHD being superior to those in the control group(|t|>2.155,P<0.05).The difference of VAS score in the exper-imental group was correlated with the difference of FMA-UE,AGT and ALT after intervention(r>0.434,P<0.05).Conclusion Closed-chain shoulder exercise training can significantly improve shoulder joint stability while alleviating shoulder pain,and effectively enhancing upper limb function in stroke patients with hemiplegic shoulder pain.Hemiplegic shoulder pain is correlated with shoulder joint stability.