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 identify the factors influencing the diagnostic accuracy of endoscopic ultrasonography (EUS) for colorectal submucosal tumors (SMT).Methods:A retrospective analysis was conducted on 330 colorectal SMT lesions (from 323 patients) diagnosed by EUS at Shenzhen Hospital of Southern Medical University from December 2015 to October 2023. Pathological diagnosis were confirmed through endoscopic resection, EUS-guided fine needle aspiration (EUS-FNA) or surgical resection. Diagnostic accuracy was calculated for each type of colorectal SMT. Univariate and multivariate logistic regression analysis were performed to identify factors affecting EUS diagnostic accuracy.Results:The overall diagnostic accuracy of EUS for colorectal SMT was 73.6% (243/330). Among 19 SMT subtypes enrolled, neuroendocrine neoplasms (51.2%, 169/330) and lipomas (15.5%, 51/330) were most prevalent, while 17 rare subtypes each accounted for <6%. Seven rare SMT (mucosal chronic inflammation, colorectal schwannoma, xanthogranulomatous inflammation, capillary hemangioma, colonic xanthoma, lymphadenoid complex, and angiomyolipoma) showed 0% diagnostic accuracy. Seven other subtypes (granular cell tumor, leiomyoma, rectal tonsil, intestinal schistosomiasis, fibrous tissue hyperplasia, gastrointestinal stromal tumor, and lymphangioma) showed accuracy <30%, whereas five subtypes (cyst, bowel endometriosis, neuroendocrine neoplasm, lipoma, and pneumatosis cystoides intestinalis) achieved >60% accuracy. Multivariate logistic regression analysis confirmed that the lesion location (left colon VS rectum: OR=0.06, 95% CI: 0.02-0.17, P<0.001; right colon VS rectum: OR=0.04, 95% CI: 0.01-0.13, P<0.001; ileocecal valve VS rectum: OR=0.09, 95% CI: 0.02-0.42, P=0.002); echogenicity (anechoic VS hypoechoic: OR=6.26, 95% CI: 1.31-29.97, P=0.022; hyperechoic VS hypoechoic: OR=13.39, 95% CI: 4.16-43.09, P<0.001) and ultrasonic layer (layer 4 VS layer 3: OR=0.22, 95% CI: 0.06-0.81, P=0.023) were independent influencing factors of EUS diagnostic accuracy for colorectal SMT. Conclusion:Neuroendocrine neoplasms and lipomas represent the most common colorectal SMT, whereas rare and uncommon SMT exhibit low EUS diagnostic accuracy. Lesion location, echogenicity, and ultrasonic layer significantly influence EUS diagnostic accuracy for colorectal SMT.

OBJECTIVE: To evaluate the efficacy and safety of Shexiang Tongxin Dropping Pill (STDP) in treating stable angina patients with phlegm-heat and blood-stasis syndrome by exercise duration and metabolic equivalents. METHODS: This multicenter, randomized, double-blind, placebo-controlled clinical trial enrolled stable angina patients with phlegm-heat and blood-stasis syndrome from 22 hospitals. They were randomized 1:1 to STDP (35 mg/pill, 6 pills per day) or placebo for 56 days. The primary outcome was the exercise duration and metabolic equivalents (METs) assessed by the standard Bruce exercise treadmill test after 56 days of treatment. The secondary outcomes included the total angina symptom score, Chinese medicine (CM) symptom scores, Seattle Angina Questionnaire (SAQ) scores, changes in ST-T on electrocardiogram and adverse events (AEs). RESULTS: This trial enrolled 309 patients, including 155 and 154 in the STDP and placebo groups, respectively. STDP significantly prolonged exercise duration with an increase of 51.0 s, compared to a decrease of 12.0 s with placebo (change rate: -11.1% vs. 3.2%, P<0.01). The increase in METs was significantly greater in the STDP group than in the placebo group (change: -0.4 vs. 0.0, change rate: -5.0% vs. 0.0%, P<0.01). The improvement of total angina symptom scores (25.0% vs. 0.0%), CM symptom scores (38.7% vs. 11.8%), reduction of nitroglycerin consumption (100.0% vs. 11.3%), and all domains of SAQ, were significantly greater with STDP than placebo (all P<0.01). The changes in Q-T intervals at 28 and 56 days from baseline were similar between the two groups (both P>0.05). Twenty-five participants (16.3%) with STDP and 16 (10.5%) with placebo experienced AEs (P=0.131), with no serious AEs observed. CONCLUSION STDP could improve exercise tolerance in patients with stable angina and phlegm-heat and blood stasis syndrome, with a favorable safety profile. (Registration No. ChiCTR-IPR-15006020).
Humans ; Double-Blind Method ; Drugs, Chinese Herbal/adverse effects* ; Male ; Female ; Middle Aged ; Angina, Stable/physiopathology* ; Aged ; Syndrome ; Treatment Outcome ; Placebos ; Tablets

Objective： The aim of this study is to explore the predictive value of biparametric magnetic resonance imaging(bpMRI)for pelvic lymph node metastasis in prostate cancer patients with PSA≤20 μg/L and establish a nomogram. Methods： The imaging data and clinical data of 363 patients undergoing radical prostatectomy and pelvic lymph node dissection in the First Affiliated Hospital of Nanjing Medical University from July 2018 to December 2023 were retrospectively analyzed. Univariate analysis and multivariate logistic regression were used to screen independent risk factors for pelvic lymph node metastasis in prostate cancer, and a nomogram of the clinical prediction model was established. Calibration curves were drawn to evaluate the accuracy of the model. Results： Multivariate logistic regression analysis showed extrocapusular extension (OR=8.08,95%CI=2.62－24.97, P<0.01), enlargement of pelvic lymph nodes (OR=4.45,95%CI=1.16－17.11,P=0.030), and biopsy ISUP grade(OR=1.97,95%CI=1.12－3.46, P=0.018)were independent risk factors for pelvic lymph node metastasis. The C-index of the prediction model was 0.834, which indicated that the model had a good prediction ability. The actual value of the model calibration curve and the prediction probability of the model fitted well, indicating that the model had a good accuracy. Further analysis of DCA curve showed that the model had good clinical application value when the risk threshold ranged from 0.05 to 0.70.Conclusion： For prostate cancer patients with PSA≤20 μg/L, bpMRI has a good predictive value for the pelvic lymph node metastasis of prostate cancer with extrocapusular extension, enlargement of pelvic lymph nodes and ISUP grade≥4.
Humans ; Male ; Prostatic Neoplasms/diagnostic imaging* ; Lymphatic Metastasis ; Retrospective Studies ; Nomograms ; Prostate-Specific Antigen/blood* ; Lymph Nodes/pathology* ; Pelvis ; Predictive Value of Tests ; Prostatectomy ; Lymph Node Excision ; Risk Factors ; Magnetic Resonance Imaging ; Logistic Models ; Middle Aged ; Aged

Growth arrest DNA damage-inducible protein 45 β (GADD45B) has been reported to be a regulatory factor for active DNA demethylation and is implicated in the modulation of synaptic plasticity and chronic stress-related psychopathological processes. However, its precise role and mechanism of action in stress susceptibility remain elusive. In this study, we found a significant reduction in GADD45B expression specifically in the ventral, but not the dorsal hippocampal CA1 (dCA1) of stress-susceptible mice. Furthermore, we demonstrated that GADD45B negatively regulates susceptibility to social stress and NMDA receptor-dependent long-term potentiation (LTP) in the ventral hippocampal CA1 (vCA1). Importantly, through pharmacological inhibition using the NMDA receptor antagonist MK801, we provided further evidence supporting the hypothesis that GADD45B potentially modulates susceptibility to social stress by influencing NMDA receptor-mediated LTP. Collectively, these results suggested that modulation of NMDA receptor-mediated synaptic plasticity is a pivotal mechanism underlying the regulation of susceptibility to social stress by GADD45B.
Animals ; Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors* ; CA1 Region, Hippocampal/drug effects* ; Male ; Stress, Psychological/physiopathology* ; Mice ; Neuronal Plasticity/drug effects* ; Long-Term Potentiation/drug effects* ; Mice, Inbred C57BL ; Antigens, Differentiation/metabolism* ; Dizocilpine Maleate/pharmacology* ; Excitatory Amino Acid Antagonists/pharmacology* ; GADD45 Proteins

ObjectiveTo investigate the effect of Niuhuang Qingxinwan （NHQXW） in improving intracerebral hemorrhage （ICH） with Tanre Fushi （phlegm-heat and fu-organ excess） syndrome by maintaining blood-brain barrier （BBB） integrity， and to explore its potential mechanism. MethodsMale mice were administered with 15% autologous feces for 3 consecutive days to simulate spontaneous Tanre Fushi syndrome， followed by surgical induction of collagenase-induced ICH on the fourth day. Mice were randomly assigned to seven groups： Sham， Sham+NHQXW-H， collagenase， collagenase+feces， and NHQXW intervention groups at low （NHQXW-L， 0.225 g·kg^-1）， medium （NHQXW-M， 0.45 g·kg^-1）， and high （NHQXW-H， 0.9 g·kg^-1） doses. Treatments were administered for 3 days after surgery. NHQXW effects on Tanre Fushi syndrome were assessed via fecal water content and small intestinal carbon propulsion rate. Protective effects of NHQXW against ICH with Tanre Fushi syndrome were evaluated by measuring hematoma volume， neurological deficits， and brain water content. BBB integrity was further assessed using Evans blue staining， hematoxylin-eosin （HE） staining， immunofluorescence， and Western blot for Claudin-5， plasmalemma vesicle-associated protein （PLVAP）， matrix metalloproteinase （MMP）-2， and MMP-9. The potential mechanism of NHQXW was investigated by detecting protein expression of protein kinase B （Akt）， extracellular signal-regulated kinase 1/2 （ERK1/2）， signal transducer and activator of transcription 3 （STAT3）， Yes-associated protein （YAP）， and their phosphorylated forms. ResultsCompared with the collagenase+feces group， NHQXW-M and NHQXW-H significantly reduced fecal water content （P<0.05， P<0.01） and intestinal propulsion rate （P<0.01）， alleviated neurological deficits （P<0.01）， decreased hematoma volume （P<0.01） and Evans blue extravasation （P<0.01）， increased Claudin-5 protein expression （P<0.05， P<0.01） and fluorescence intensity （P<0.01）， and decreased PLVAP protein expression （P<0.01） and fluorescence intensity （P<0.05， P<0.01）， as well as MMP-2 （P<0.05， P<0.01） and MMP-9 （P<0.01） expression. NHQXW-H downregulated p-Akt （P<0.05）， p-ERK1/2 （P<0.05）， p-STAT3 （P<0.01）， and p-YAP （P<0.05）， with the most significant effect observed on STAT3 phosphorylation. ConclusionNHQXW effectively alleviates neurological deficits and BBB injury in ICH mice with Tanre Fushi syndrome， primarily by inhibiting STAT3 activation.

This study compared the differences in intestinal absorption characteristics of eleven active components in Rubus multibracteatus(RM) extract(protocatechuic acid, tiliroside, scutellarin, luteoloside, astragalin, epicatechin, catechin, xanthotoxin, p-coumaric acid, caffeic acid, and apigenin-7-O-glucuronide) between normal rats and inflammatory pain model rats using the in-vitro everted intestinal sac model. The RM extract was administered at absorption concentrations of 25.0, 50.0, and 100.0 mg·mL~(-1). The contents of the eleven components in intestinal absorption solution samples were quantified by ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS), and their cumulative absorption(Q) and absorption rate constant(K_a) were calculated to evaluate the absorption characteristics of these components in normal rats and inflammatory pain model rats. The results show that except for catechin, epicatechin, and caffeic acid, the cumulative absorption-time curves of the other eight components(protocatechuic acid, tiliroside, scutellarin, luteoloside, astragalin, xanthotoxin, p-coumaric acid, and apigenin-7-O-glucuronide) exhibit an upward trend without saturation, with correlation coefficients(R~2) all > 0.9, indicating linear absorption. However, the overall absorption of all components is not dose-dependent with increasing concentration, suggesting that their absorption mechanisms are not solely passive diffusion. In both normal and model rats, the jejunum shows the highest absorption for all components except xanthotoxin. The overall absorption of seven components(excluding protocatechuic acid, caffeic acid, apigenin-7-O-glucuronide, and luteoloside) in normal rats is better than that in model rats across all intestinal segments. These findings indicate that the pathological state of inflammatory pain alters the intestinal absorption of RM extract, and its mechanism needs further investigation.
Animals ; Rats ; Intestinal Absorption/drug effects* ; Male ; Rats, Sprague-Dawley ; Drugs, Chinese Herbal/metabolism* ; Disease Models, Animal ; Pain/metabolism* ; Intestines/drug effects* ; Intestinal Mucosa/metabolism*

Objective:To identify the factors influencing the diagnostic accuracy of endoscopic ultrasonography (EUS) for colorectal submucosal tumors (SMT).Methods:A retrospective analysis was conducted on 330 colorectal SMT lesions (from 323 patients) diagnosed by EUS at Shenzhen Hospital of Southern Medical University from December 2015 to October 2023. Pathological diagnosis were confirmed through endoscopic resection, EUS-guided fine needle aspiration (EUS-FNA) or surgical resection. Diagnostic accuracy was calculated for each type of colorectal SMT. Univariate and multivariate logistic regression analysis were performed to identify factors affecting EUS diagnostic accuracy.Results:The overall diagnostic accuracy of EUS for colorectal SMT was 73.6% (243/330). Among 19 SMT subtypes enrolled, neuroendocrine neoplasms (51.2%, 169/330) and lipomas (15.5%, 51/330) were most prevalent, while 17 rare subtypes each accounted for <6%. Seven rare SMT (mucosal chronic inflammation, colorectal schwannoma, xanthogranulomatous inflammation, capillary hemangioma, colonic xanthoma, lymphadenoid complex, and angiomyolipoma) showed 0% diagnostic accuracy. Seven other subtypes (granular cell tumor, leiomyoma, rectal tonsil, intestinal schistosomiasis, fibrous tissue hyperplasia, gastrointestinal stromal tumor, and lymphangioma) showed accuracy <30%, whereas five subtypes (cyst, bowel endometriosis, neuroendocrine neoplasm, lipoma, and pneumatosis cystoides intestinalis) achieved >60% accuracy. Multivariate logistic regression analysis confirmed that the lesion location (left colon VS rectum: OR=0.06, 95% CI: 0.02-0.17, P<0.001; right colon VS rectum: OR=0.04, 95% CI: 0.01-0.13, P<0.001; ileocecal valve VS rectum: OR=0.09, 95% CI: 0.02-0.42, P=0.002); echogenicity (anechoic VS hypoechoic: OR=6.26, 95% CI: 1.31-29.97, P=0.022; hyperechoic VS hypoechoic: OR=13.39, 95% CI: 4.16-43.09, P<0.001) and ultrasonic layer (layer 4 VS layer 3: OR=0.22, 95% CI: 0.06-0.81, P=0.023) were independent influencing factors of EUS diagnostic accuracy for colorectal SMT. Conclusion:Neuroendocrine neoplasms and lipomas represent the most common colorectal SMT, whereas rare and uncommon SMT exhibit low EUS diagnostic accuracy. Lesion location, echogenicity, and ultrasonic layer significantly influence EUS diagnostic accuracy for colorectal SMT.