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.

Objective: To investigate the role and mechanism of the heat-clearing and detoxifying drug Laggerae Herba in regulating the nuclear factor-erythroid 2-related factor-2(Nrf2)/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) signaling pathway to inhibit ferroptosis and improve chronic heart failure induced by transverse aortic arch constriction in mice. Methods: Twenty-four male ICR mice were divided into the sham (n=6) and transverse aortic arch constriction groups (n=18) according to the random number table method. The transverse aortic arch constriction group underwent transverse aortic constriction surgery to establish models. After modeling, the transverse aortic arch constriction group was further divided into the model, captopril, and Laggerae Herba groups according to the random number table method, with six mice per group. The captopril (15 mg/kg) and Laggerae Herba groups (1.95 g/kg) received the corresponding drugs by gavage, whereas the sham operation and model groups were administered the same volume of ultrapure water by gavage once a day for four consecutive weeks. After treatment, the cardiac function indexes of mice in each group were detected using ultrasound. The heart mass and tibia length were measured to calculate the ratio of heart weight to tibia length. Hematoxylin and eosin staining were used to observe the pathological changes in myocardial tissue. Masson staining was used to observe the degree of myocardial fibrosis. Wheat germ agglutinin staining was used to observe the degree of myocardial cell hypertrophy. Prussian blue staining was used to observe the iron deposition in myocardial tissue. An enzyme-linked immunosorbent assay was used to detect the amino-terminal pro-brain natriuretic peptide (NT-proBNP) and glutathione (GSH) contents in mice serum. Colorimetry was used to detect the malondialdehyde (MDA) content in mice serum. Western blotting was used to detect the Nrf2, GPX4, SLC7A11, and ferritin heavy chain 1 (FTH1) protein expressions in mice cardiac tissue. Results: Compared with the sham group, in the model group, the ejection fraction (EF) and fractional shortening (FS) of mice decreased, the left ventricular end-systolic volume (LVESV) and left ventricular end-systolic diameter (LVESD) increased, the left ventricular anterior wall end-systolic thickness (LVAWs) and left ventricular posterior wall end-systolic thickness (LVPWs) decreased, the ratio of heart weight to tibia length increased, the myocardial tissue morphology changed, myocardial fibrosis increased, the cross-sectional area of myocardial cells increased, iron deposition appeared in myocardial tissue, the serum NT-proBNP and MDA levels increased, the GSH level decreased, and Nrf2, GPX4, SLC7A11, and FTH1 protein expressions in cardiac tissue decreased (P<0.05). Compared with the model group, in the captopril and Laggerae Herba groups, the EF, FS, and LVAWs increased, the LVESV and LVESD decreased, the ratio of heart weight to tibia length decreased, the myocardial cells were arranged neatly, the degree of myocardial fibrosis decreased, the cross-sectional area of myocardial cells decreased, the serum NT-proBNP level decreased, and the GSH level increased. Compared with the model group, the LVPWs increased, the iron deposition in myocardial tissue decreased, the serum MDA level decreased, and Nrf2, GPX4, SLC7A11, and FTH1 protein expressions in cardiac tissue increased (P<0.05) in the Laggerae Herba group. Conclusion Laggerae Herba improves the cardiac function of mice with chronic heart failure caused by transverse aortic arch constriction, reduces the pathological remodeling of the heart, and reduces fibrosis. Its mechanism may be related to Nrf2/SLC7A11/GPX4 pathway-mediated ferroptosis.

ObjectiveTo explore the molecular mechanism of aerobic exercise to improve hippocampal neuronal degeneration by regulating tryptophan metabolic pathway. Methods60 SPF-grade C57BL/6J male mice were divided into a young group (2 months old, n=30) and a senile group (12 months old, n=30), and each group was further divided into a control group (C/A group, n=15) and an exercise group (CE/AE group, n=15). An aerobic exercise program was used for 8 weeks. Learning memory ability was assessed by Y-maze, and anxiety-depression-like behavior was detected by absent field experiment. Hippocampal Trp levels were measured by GC-MS. Nissl staining was used to observe the number and morphology of hippocampal neurons, and electron microscopy was used to detect synaptic ultrastructure. ELISA was used to detect the levels of hippocampal Trp,5-HT, Kyn, KATs, KYNA, KMO, and QUIN; Western blot was used to analyze the activities of TPH2, IDO1, and TDO enzymes. ResultsGroup A mice showed significant decrease in learning and memory ability (P<0.05) and increase in anxiety and depressive behaviors (P<0.05); all of AE group showed significant improvement (P<0.05). Hippocampal Trp levels decreased in group A (P<0.05) and increased in AE group (P<0.05). Nidus vesicles were reduced and synaptic structures were degraded in group A (P<0.05), and both were significantly improved in group AE (P<0.05). The levels of Trp, 5-HT, KATs, and KYNA were decreased (P<0.05) and the levels of Kyn, KMO, and QUIN were increased (P<0.05) in group A. The activity of TPH2 was decreased (P<0.05), and the activities of IDO1 and TDO were increased (P<0.05). The AE group showed the opposite trend. ConclusionThe aging process significantly reduces the learning memory ability and increases the anxiety-depression-like behavior of mice, and leads to the reduction of the number of nidus vesicles and degenerative changes of synaptic structure in the hippocampus, whereas aerobic exercise not only effectively enhances the spatial learning memory ability and alleviates the anxiety-depression-like behavior of aging mice, but also improves the morphology and structure of neurons in hippocampal area, which may be achieved by the mechanism of regulating the tryptophan metabolic pathway.

Objective: This study aimed to construct an animal model of heart failure with preserved ejection fraction (HFpEF) that integrates disease and syndrome based on the "deficiency-blood stasis-toxin" pathogenesis and to evaluate it comprehensively. Methods: The HFpEF mouse model was constructed using a combination of Nω-nitro-L-arginine methyl ester (L-NAME) and a high-fat diet. According to the random number table method, SPF-grade male C57BL/6J mice were randomly assigned to the control, L-NAME, high-fat diet, and model groups, 10 in each group. Comprehensive observations and data collection on macroscopic signs (e.g., fur condition, mental state, stool and urine, oral and nasal condition, paw and body condition, etc.) and cardiac function were performed after 10 and 16 weeks of model induction. Additionally, the syndrome evolution was elucidated based on diagnostic criteria for clinical syndromes of heart failure. Furthermore, pathological and molecular biological examinations of myocardial tissue were performed to assess the stability and reliability of the model. Results: Mice in the model group showed typical characteristics of syndrome of qi deficiency and blood stasis, as well as syndrome of internal heat accumulation, including lethargy, slow response, dull paw color and oral/nasal color, exercise intolerance, abnormal platelet activation, dry feces, and dark yellow urine. The time window for these syndromes was between 10 and 16 weeks post-modeling. Cardiac function assessments revealed severe diastolic dysfunction, concentric myocardial hypertrophy, and myocardial fibrosis in the model group. Pathological examinations showed a significantly increased collagen deposition in the myocardial interstitium, enlarged cross-sectional area of cardiomyocytes, and sparse coronary microvasculature in the model group. Molecular biological analyses indicated marked activation of the inducible nitric oxide synthase/nuclear factor kappa-light-chain-enhancer of activated B cells/NOD-like receptor family pyrin domain containing 3 inflammatory pathway and significantly elevated inflammation levels in the myocardial tissue of the model group. Although mice in the L-NAME and high-fat diet groups also showed certain manifestations of qi deficiency syndrome, the substantial cardiac damage was relatively limited compared to the control group. Conclusion This study has constructed an animal model of HFpEF that integrates disease and syndrome based on the "deficiency-blood stasis-toxin" pathogenesis. The macroscopic and microscopic characteristics of this model are consistent with the manifestations of syndrome of qi deficiency and blood stasis, toxin syndrome, and syndrome of internal heat accumulation. Moreover, it can stably simulate the HFpEF state and reflect phenotypic changes in human disease. This model provides a suitable experimental platform to explore the pathogenesis of HFpEF, evaluate the effectiveness of traditional Chinese medicine (TCM) treatment regimens, and promote in-depth research on TCM syndromes of heart failure.

ObjectiveTo observe the effect of Banxia Xiexintang （BXT） on the proliferation of human gastric cancer HGC-27， MKN-45， and AGS cells and its mechanism. MethodCell counting kit-8 （CCK-8） was used to detect the effects of different concentrations of BXT-containing serum （5%， 10%， and 20%） on the proliferation of HGC-27， MKN-45， and AGS cells. A mitochondrial membrane potential probe （TMRE） was used to detect the expression of mitochondrial membrane potential in cells. A kit was used to detect iron ion （Fe²⁺） content， lipid peroxide （LPO）， and superoxide dismutase （SOD） activity. Western blot was used to detect the protein expression levels of glycogen synthase3β （GSK3β）， phosphorylated GSK3β （p-GSK3β）， nuclear factor E₂ related factor 2 （Nrf2）， and glutathione peroxidase 4 （GPX4）. The real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of member 11 of the cystine/glutamic acid reverse transporter solute vector family 7 （SLC7A11）， member 2 of the heavy chain solute vector family 3 （SLC3A2）， transferrin receptor 3 （TFRC）， and tumor protein （TP）53. ResultCCK-8 results showed that BXT and capecitabine could significantly reduce the survival rate of three kinds of gastric cancer cells after treatment with drug-containing serum for 24 h （P<0.01）. After 48 h of intervention with drug-containing serum， the survival rate of three kinds of gastric cancer cells was significantly decreased in both the capecitabine group and the BXT group compared with the blank group. The BXT group was dose-dependent， with 20% BXT having the most significant effect （P<0.01）. In terms of biochemical indicators of ferroptosis， compared with the blank group， BXT and capecitabine significantly decreased the expression of mitochondrial membrane potential （P<0.01） and SOD activity （P<0.01） and significantly increased the contents of LPO and Fe²⁺ （P<0.01）， so as to improve the sensitivity of gastric cancer cells to ferroptosis. In terms of the Nrf2/GPX4 pathway， compared with the blank group， the BXT group could reduce the protein expressions of p-GSK3β， Nrf2， and GPX4 （P<0.01） in gastric cancer cells and increase mRNA expressions of SLC7A11 and SLC3A2 （P<0.05）. It could also increase the protein expression of GSK3β （P<0.01） and mRNA expression of TP53 and TFRC （P<0.05， P<0.01） in gastric cancer cells. Inhibition of the Nrf2/GPX4 pathway induces ferroptosis in gastric cancer cells. Compared with the capecitabine group， the 20% BXT group showed a more obvious effect. ConclusionBanxia Xiexintang can induce ferroptosis in gastric cancer cells HGC-27， MKN-45， and AGS by inhibiting the Nrf2/GPX4 pathway.

Objective To investigate the clinical efficacy of modified Fuzheng Yiliu Decoction(composed of Astragali Radix,Codonopsis Radix,Ligustri Lucidi Fructus,Hedyotis Diffusae Herba,Moutan Cortex,Visci Herba,etc.)combined with XELOX regimen(Oxaliplatin plus Capecitabine)for the treatment of postoperative patients with advanced gastric cancer of qi and yin deficiency type.Methods A total of 80 postoperative patients with advanced gastric cancer of qi and yin deficiency type were randomly divided into the Chinese medicine group and the control group,with 40 cases in each group.Both groups received chemotherapy with XELOX regimen,while the Chinese medicine group was given modified Fuzheng Yiliu Decoction.Three weeks constituted a course of treatment,the medication of Chinese medicine decoction lasted for two weeks or more in each course of treatment,and a total of 8 courses of treatment were performed.The incidence of adverse reactions during chemotherapy was monitored and changes in serum tumor markers of serum carcinoembryonic antigen(CEA),carbohydrate antigen 199(CA199)and alpha-fetoprotein(AFP)were observed in the two groups before and after treatment.Moreover,the patients'quality of life was assessed by the scores of Karnofsky's Performance Status(KPS)and World Health Organization Quality of Life Measurement Scale(WHOQOL-100).Long-term follow-up was carried out for the evaluation of the prognostic indicators such as overall survival and one-year and 2-year overall survival rates.Results(1)Patients in the two groups were all followed up,and the median follow-up time was 27 months(95%CI:23.59-27.86).(2)After treatment,the levels of serum CEA and AFP in the Chinese medicine group were significantly lower than those before treatment(P＜0.05 or P＜0.01),while serum CA199 tended to decrease compared with those before treatment,but the difference was not statistically significant(P＞0.05);in the control group,the levels of serum CEA,CA199,and AFP were not significantly decreased after treatment(P＞0.05).The intergroup comparison showed that the decrease of serum CEA,CA199 and AFP levels in the Chinese medicine group was significantly superior to that in the control group(P＜0.05 or P＜0.01).(3)The adverse reactions during chemotherapy in the two groups mainly involved bone marrow suppression,gastrointestinal reactions and liver function abnormalities,etc.The incidences of all adverse reactions in the Chinese medicine group tended to be lower than those in the control group,but the differences were not statistically significant(P＞0.05).(4)After treatment,the KPS scores of patients in both groups were improved compared with those before treatment(P＜0.01),and the improvement in the Chinese medicine group was significantly superior to that in the control group(P＜0.01).(5)After treatment,the scores of the four dimensions of WHOQOL-100 such as health status,mobility,life feelings,and other activities of daily life in the Chinese medicine group were significantly improved compared with the pre-treatment(P＜0.05),whereas there was no significant improvement in the control group(P＞0.05).The intergroup comparison showed that the improvement of the scores of each dimension of the WHOQOL-100 in the Chinese medicine group was significantly superior to that in the control group(P＜0.05 or P＜0.01).(6)The median survival in the Chinese medicine group was 29.0 months(95%CI:25.95-31.70)and that in the control group was 22.0 months(95%CI:19.67-25.58),indicating that the median survival was significantly prolonged in Chinese medicine group(P＜0.01).The one-year and 2-year postoperative survival rates were 97.5%and 77.5%in the Chinese medicine group and 92.5%and 47.5%in the control group,respectively.The intergroup comparison showed that the one-year and 2-year postoperative survival rates in the Chinese medicine group were higher than those in the control group(P＜0.01).Conclusion Modified Fuzheng Yiliu Decoction can effectively alleviate the adverse reactions during adjuvant chemotherapy for postoperative patients with advanced gastric cancer of qi and yin deficiency type,improve the quality of life of patients,and prolong the survival time of patients.

Objective To analyze the detection efficiency of p16INK4a protein combined with human papillomavirus and liquid-based cytology(LCT)in the screening of cervical precancerous lesions,and to provide a basis for cervical cancer preven-tion and treatment.Methods The results of p16INK4a staining of cervical epithelial cells,human papillomavirus testing and cer-vical cytology were analyzed in 139 inpatients at Guangzhou Women's and Children's Medical Center between January 2019 and December 2020.Of them,there were 111 patients with cervical intraepithelial neoplasia(CIN)and 28 cases of cervical inflam-matory disease.The efficacy of the three methods alone and in combination to screen for CIN lesions was compared.Results In the detection of CIN patients,the sensitivity of p16INK4a,microfluidic microarray and cervical cytology for detecting CIN and a-bove lesions was 91.89% ,94.59% and82.88% ,with specificity of 57.14% ,17.86% and46.43% ,and AUC of 0.75,0.56 and 0.65,respectively;while the sensitivity of"p16INK4a+LCT","p16INK4a+hrHPV","LCT+hrHPV"and their sen-sitivity were 96.40% ,97.30% ,94.59% and 99.10% ,their specificity was 85.71% ,92.86% ,89.29% and 92.86% ,and the AUC was 0.91,0.95,0.92 and 0.96,respectively.Conclusion The combined p16INK4a and hrHPV test helps to improve diagnostic accuracy and early detection,thus allowing for earlier intervention or treatment.This combined application allows for more accurate identification of low-grade and high-grade cervical intraepithelial neoplasia,providing more information for indi-vidualized patient management.

OBJECTIVE: To investigate the effect and possible mechanism of hydroxysafflor yellow A (HSYA) on human immortalized keratinocyte cell proliferation and migration. METHODS: HaCaT cells were treated with HSYA. Cell proliferation was detected by the cell counting kit-8 assay, and cell migration was measured using wound healing assay and Transwell migration assay. The mRNA and protein expression levels of heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF), EGF receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), mammalian target of rapamycin (mTOR), and hypoxia-inducible factor-1α (HIF-1α) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA. The expression of circ_0084443 was detected by qRT-PCR. RESULTS: HSYA (800 µmol/L) significantly promoted HaCaT cell proliferation and migration (P<0.05 or P<0.01). It also increased the mRNA and protein expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and increased the phosphorylation levels of PI3K and AKT (P<0.05 or P<0.01). Furthermore, HSYA promoted HaCaT cell proliferation and migration via the HBEGF/EGFR and PI3K/AKT/mTOR signaling pathways (P<0.01). Circ_0084443 attenuated the mRNA expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α (P<0.05). HSYA inhibited the circ_0084443 expression, further antagonized the inhibition of circ_0084443 on HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and promoted the proliferation of circ_0084443-overexpressing HaCaT cells (P<0.05 or P<0.01). However, HSYA could not influence the inhibitory effect of circ_0084443 on HaCaT cell migration (P>0.05). CONCLUSION HSYA played an accelerative role in HaCaT cell proliferation and migration, which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways, and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinase ; Phosphatidylinositol 3-Kinases/metabolism* ; ErbB Receptors/genetics* ; TOR Serine-Threonine Kinases/metabolism* ; Cell Proliferation ; RNA, Messenger/genetics* ; Cell Movement ; Cell Line, Tumor ; Chalcone/analogs & derivatives* ; Quinones

OBJECTIVE To investigate the effect of pachymic acid （PA） on renal function and fibrosis in chronic renal failure （CRF） rats and its potential mechanism based on the Ras homolog gene family member A （RhoA）/Rho-associated coiled-coil forming protein kinase （ROCK） signaling pathway. METHODS Using male SD rats as subjects， the CRF model was established by 5/6 nephrectomy； the successfully modeled rats were divided into model group， PA low-dose， medium-dose and high-dose groups （5， 10， 20 mg/kg PA）， high-dose PA+ROCK pathway activator lysophosphatidic acid （LPA） group （20 mg/kg PA+1 mg/kg LPA）， with 15 rats in each group. Another 15 rats were selected as the sham operation group with only the kidney exposed but not excised. The rats in each drug group were gavaged and/or injected with the corresponding liquid via the caudal vein， once a day， for 12 consecutive weeks. During the experiment， the general condition of rats was observed in each group. After the last administration， the serum renal function indexes （blood urea nitrogen， serum creatinine， uric acid） of rats in each group were detected， the renal histopathological changes were observed； the renal tubule injury score and the area of renal fibrosis were quantified. The levels of oxidative stress indexes [malondialdehyde （MDA）， superoxide dismutase （SOD）] and inflammatory factors （tumor necrosis factor-α， interleukin-1β， interleukin-6）， the positive expression rates of connective tissue growth factor （CTGF） and collagen Ⅰ were detected as well as the expression levels of pathway-related proteins （RhoA， ROCK1） and fibrosis- related proteins （transforming growth factor-β1， bare corneum homologs 2， α-smooth muscle actin） were determined. RESULTS Compared with the sham operation group， the rats in model group had reduced diet， smaller body size， listless spirit and sluggish response， reduced and atrophied glomeruli， dilated renal tubules with chaotic structure， and a large number of inflammatory cells infiltrated interstitium； the serum levels of renal function indexes， renal tubule injury score， renal fibrosis area proportion， the levels of MDA and inflammatory factors， the positive expression rates of CTGF and collagen Ⅰ， and the expression levels of pathway-related proteins and fibrosis-related proteins in renal tissues were significantly increased， while SOD level was significantly decreased （P＜0.05）. Compared with the model group， the general condition and pathological injuries of kidney tissue of rats in PA groups were improved to varying degrees，and the above quantitative indexes were significantly improved in a dose-dependent manner （P＜0.05）. LPA could significantly reverse the improvement effect of PA on the above indicators （P＜0.05）. CONCLUSIONS PA can improve renal function and alleviate renal fibrosis in CRF rats， which may be related to inhibiting the activation of RhoA/ROCK signaling pathway.

Objective To observe the efficacy and safety of Morinda officinalis oligosaccharides in the continuation treatment of mild and moderate depression.Methods An open,single-arm,multi-center design was adopted in our study.Adult patients with mild and moderate depression who had received acute treatment of Morinda officinalis oligosaccharides were enrolled and continue to receive Morinda officinalis oligosaccharides capsules for 24 weeks,the dose remained unchanged during continuation treatment.The remission rate,recurrence rate,recurrence time,and the change from baseline to endpoint of Hamilton Depression Scale(HAMD),Hamilton Anxiety Scale(HAMA),Clinical Global Impression-Severity(CGI-S)and Arizona Sexual Experience Scale(ASEX)were evaluated.The incidence of treatment-related adverse events was reported.Results The scores of HAMD-17 at baseline and after treatment were 6.60±1.87 and 5.85±4.18,scores of HAMA were 6.36±3.02 and 4.93±3.09,scores of CGI-S were 1.49±0.56 and 1.29±0.81,scores of ASEX were 15.92±4.72 and 15.57±5.26,with significant difference(P＜0.05).After continuation treatment,the remission rate was 54.59％(202 cases/370 cases),and the recurrence rate was 6.49％(24 cases/370 cases),the recurrence time was(64.67±42.47)days.The incidence of treatment-related adverse events was 15.35％(64 cases/417 cases).Conclusion Morinda officinalis oligosaccharides capsules can be effectively used for the continuation treatment of mild and moderate depression,and are well tolerated and safe.