ObjectiveThis study employs a special conformational engineering (CE) technology to construct an α-chymotrypsin-like active center, which includes a catalytic triad, an oxyanion hole, and a substrate-binding site, on silver nanoparticles (AgNPs), thereby creating an AgNP-based artificial hydrolase with high catalytic activity. This study provides a new approach for the design of highly efficient artificial enzymes and enzyme-mimicking. MethodsAgNPs were chosen as the scaffold to build the an α-chymotrypsin-like active center. A special CE procedure enables the designed peptide, Triad5, to adopt an α‑helical conformation on AgNPs, with the key catalytic residues located on one side of the α-helix forming a catalytic active center with a catalytic triad, an oxyanion hole, and a substrate-binding site. The CE procedure consists of three steps, including conformation induction via trifluoroethanol (TFE), conformation stabilization on AgNPs via Ag-S bonds, and TFE removal via lyophilization. Circular dichroism (CD) spectra were used to confirm the formation and stabilization of the α-helix conformation. Mutations of the key residues combined with stopped-flow kinetic experiments were used to demonstrate the indispensability of each key residue and the synergistic effects among the catalytic triad, the oxyanion hole, and the substrate-binding site. ResultsCD spectra show that the designed Triad5 alone is in random coil conformation; when conjugated on AgNPs, Triad5 still remains largely unstructured; but after the CE treatment, Triad5 adopts a typical α-helical conformation on AgNPs as designed, thus produces an AgNP-based artificial hydrolase, Silverzyme. Silverzyme exhibits extremely high hydrolytic activity towards p-nitrophenyl acetate (p-NPA), with an extremely high catalytic turnover number per active site of 3.5 s^-1, which is even higher than that of α-chymotrypsin. As a comparison, the AgNP-Triad5 conjugate without CE treatment shows much lower catalytic activity than Silverzyme, highlighting the important role of the right conformation of the active center for the catalytic activity and the power of the CE treatment. When the key residues of the catalytic triad of Silverzyme were mutated to alanine, the overall catalytic efficiency of this mutant dropped by about 2 orders of magnitude, unambiguously demonstrating the key role of the designed catalytic triad. Similarly, when the residues for the oxyanion hole were deleted, the mutant with the intact catalytic triad also showed significantly decreased catalytic activity, highlighting the indispensable role of the oxyanion hole for the catalytic activity. Unexpectedly, when both the catalytic triad and the oxyanion hole were kept intact, a slight change of the binding site also resulted in significantly decreased catalytic activity, indicating that the designed binding site is at the right position to align the substrate in the right orientation in the active center for catalytic hydrolysis. These results confirm the synergy among the catalytic triad, the oxyanion hole, and the substrate-binding site, indicating successful mimicking of the active center of α-chymotrypsin. Moreover, Silverzyme shows better thermal stability than α-chymotrypsin, and can even hydrolyze the tough non-activated ester diethyl phthalate, a priority pollutant by the United States Environmental Protection Agency (USEPA). ConclusionThis study successfully mimicked the complex catalytic active center of α-chymotrypsin using a conformational engineering strategy, and produced a highly active artificial hydrolase with a well-defined structure and catalytic mechanism. The findings highlight the significant potential of conformational engineering.

Neuroinflammatory responses play an important role in the pathogenesis of various diseases, particularly those affecting the central nervous system. Inhibition of neuroinflammation is a crucial therapeutic strategy for the management of central nervous system disorders. The intestinal microbial-gut-brain axis serves as a key regulatory pathway that modulates neuroinflammatory processes. Intestinal flora metabolites such as short-chain fatty acids, indoles and their derivatives, lipopolysaccharides, trimethylamine oxide, and secondary bile acids exert direct or indirect effects on neuroinflammation. Studies have shown that electroacupuncture (EA) modulates the composition of the intestinal microbiota and its metabolites, while also suppressing neuroinflammation by targeting the TLR4/NF- κ B, NLRP3/caspase-1, and microglial cell M2-type transformation pathways. This review discusses the mechanisms by which EA regulates neuroinflammation via intestinal microbiota and its metabolites, providing information and a foundation for further investigation of the precise therapeutic mechanisms of EA in neurological disorders.
Humans ; Gastrointestinal Microbiome ; Electroacupuncture ; Neuroinflammatory Diseases/metabolism* ; Animals

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: Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health. Analysis of these mixture exposures presents several key challenges for environmental epidemiology and risk assessment, including high dimensionality, correlated exposure, and subtle individual effects. METHODS: We proposed a novel statistical approach, the generalized functional linear model (GFLM), to analyze the health effects of exposure mixtures. GFLM treats the effect of mixture exposures as a smooth function by reordering exposures based on specific mechanisms and capturing internal correlations to provide a meaningful estimation and interpretation. The robustness and efficiency was evaluated under various scenarios through extensive simulation studies. RESULTS: We applied the GFLM to two datasets from the National Health and Nutrition Examination Survey (NHANES). In the first application, we examined the effects of 37 nutrients on BMI (2011-2016 cycles). The GFLM identified a significant mixture effect, with fiber and fat emerging as the nutrients with the greatest negative and positive effects on BMI, respectively. For the second application, we investigated the association between four pre- and perfluoroalkyl substances (PFAS) and gout risk (2007-2018 cycles). Unlike traditional methods, the GFLM indicated no significant association, demonstrating its robustness to multicollinearity. CONCLUSION GFLM framework is a powerful tool for mixture exposure analysis, offering improved handling of correlated exposures and interpretable results. It demonstrates robust performance across various scenarios and real-world applications, advancing our understanding of complex environmental exposures and their health impacts on environmental epidemiology and toxicology.
Humans ; Environmental Exposure/analysis* ; Linear Models ; Nutrition Surveys ; Environmental Pollutants ; Body Mass Index

Objective To investigate the dosimetric differences in preoperative short-course volumetric modulated arc therapy(VMAT)for rectal cancer using different fluence smoothing(FS)levels in the Monaco Treatment Planning System(Monaco TPS).Methods Twenty rectal cancer patients who received preoperative neoadjuvant short-course VMAT at some hospital from September 2021 to December 2022 were retrospectively selected.Four groups of radiotherapy plans were formulated using the Monaco TPS for each case,which were classified into an off group,a low group,a medium group and a high group based on the FS levels.Then the four groups were compared in terms of the dosimetric parameters,monitor unit and number of the segments in the planning target volume(PTV)and organ at risk(OAR).Statistical analysis was performed using SPSS 27.0 software.Results All the four groups had the doses to the target volume meeting clinical requirements,which had no significant differences in the doses to 5％(D5％)and 95％(D95％)to the target volume and the maximum dose(Dmax),minimum dose(Dmin),mean dose(Dmean)and conformity index(all P＞0.05).Statistical differences were found between the homogeneity indexes of the four groups(P＜0.05),with the medium group behaving the best.The number of the segments rose while the mornitor units decreased siginificantly with the increase of FS levels,with the differences being statistically significant(P＜0.05).There were no significant differences between the V25,V20,V15 and V10 of the small intestine,the V25 and V20 of the bladder and the V15 and V10 of the left and right femur(all P＞0.05).Conclusion In preoperative short-course VMAT for rectal cancer,clinical requirements can be met with different FS levels in the Monaco TPS,and medium-level FS results in optimal overall dose distribution in terms of treatment planning.[Chinese Medical Equipment Journal,2025,46(5):48-53]

Objective:To evaluate the effect of acupuncture on postoperative delirium (POD) in diabetic patients undergoing surgery under general anesthesia.Methods:In this randomized controlled trial, 92 diabetic patients of either sex, aged 30-80 yr, with a body mass index of 18-28 kg/m 2, of American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, scheduled for elective surgery under general anesthesia, were divided into 2 groups ( n=46 each) using a table of random numbers: control group (group C) and acupuncture group (group A). Group A received acupuncture at the Baihui (GV20), Shenting (GV24) and Sishencong (EX-HN1) acupoints before anesthesia. The needles were retained for 30 min, with manual stimulation applied every 10 min for 10 s each time. After 4 stimulations, routine anesthesia was carried out. Group C received routine anesthesia only. Regional cerebral oxygen saturation was recorded on admission to the operating room (T 0), after anesthesia induction (T 1), at the start of surgery (T 2), at the end of surgery (T 3), and immediately after tracheal extubation (T 4). The POD developed within 3 days after surgery was assessed. The occurrence of needle-related adverse effects such as fainting, subcutaneous bleeding, and local paresthesia was recorded. Results:Compared with group C, the incidence of POD was significantly reduced, and the regional cerebral oxygen saturation was increased at T 1, 4 in group A ( P<0.05). Conclusions:Acupuncture can decrease the development of POD in diabetic patients undergoing surgery under general anesthesia, which is related to an increase in regional cerebral oxygen saturation.

Aim To investigate the regulatory mecha-nisms of donepezil on the expression and enzymatic ac-tivity of cytochrome P450 3A4(CYP3A4),elucidate the synergistic impact of hypoxia on CYP3A4 function,and reveal its potential association with drug-induced cardiotoxicity,particularly QT interval prolongation.Methods Western blot,co-immunoprecipitation,and gene knockdown techniques were employed to evaluate the effects of donepezil and hypoxia on CYP3A4 pro-tein expression.CYP3A4 enzymatic activity was as-sessed using an in vitro incubation system with rat liver microsomes combined with high-performance liquid chromatography(HPLC),and the half-maximal inhib-itory concentration(IC50)was determined.Results Donepezil(10 μmol·L-1)and hypoxia reduced CYP3A4 protein expression to 31.75％and 45.90％of the control levels,respectively.Both interventions activated the gp78-mediated ubiquitin-proteasome path-way,significantly increasing CYP3A4 ubiquitination levels by 2.1-fold compared to the control group,thereby promoting proteasomal degradation.Donepezil inhibited CYP3A4 enzyme activity with an IC50 of 83.4μmol·L-1,and hypoxia synergistically enhanced this inhibitory effect,reducing the IC50 to 20.79 μmol·L-1.Conclusion Donepezil downregulates CYP3A4 function through dual mechanisms involving ubiquitin-mediated proteasomal degradation and direct enzymatic inhibition.Hypoxia potentiates this effect,leading to impaired metabolism of CYP3A4 substrate drugs,ele-vated plasma drug concentrations(1.6-2.3-fold in-crease compared to normal metabolic conditions),and an increased risk of QT interval prolongation and other forms of cardiotoxicity.

Abnormal expression of CMTM4 protein is closely related to tumour occurrence,development and prognosis.Although the important role of CMTM4 in tumours has been gradually manifested,its spe-cific mechanism of action in cervical cancer remains unclear.The aim of this study was to investigate the relationship between CMTM4 expression and clinicopathological features in cervical cancer and study its mechanism.Immunohistochemistry and Western blot were used to detect the expression level of CMTM4 in cancer tissues and paracancerous tissues,and it was found that CMTM4 was significantly under-ex-pressed in cervical cancer tissues(P＜0.001).The chi-square test analysed the relationship between high and low CMTM4 expression and the clinical and pathological characteristics of cervical cancer pa-tients and results found that CMTM4 expression was correlated with the number of births,HPV infection status,pathological type,FIGO stage and lymph node metastasis.Data from Western blot and RT-qPCR found that CMTM4 protein and mRNA levels in HaCaT cells were significantly higher than that of C-33A cells,HeLa cells,U14 cells,and HT-3 cells.Among them,the most significant change in CMTM4 ex-pression was observed in C-33A cells,so the C-33A cell line was selected for subsequent overexpression experiments.CCK-8 analysis found that the proliferation ability of C-33A cervical cancer cells in the pcDNA-CMTM4 group was significantly lower than that in the pcDNA-NC group(P＜0.001).Flow cy-tometry and Western blot results indicated that CMTM4 overexpression promoted apoptosis(P＜0.001),significantly increased Bax(P＜0.001)and cleaved caspase 3(P＜0.05)protein levels,and significant-ly decreased Bcl-2 protein level(P＜0.01).Western blot results further found that CMTM4 overexpres-sion significantly reduced the protein levels of p-PI3K(P＜0.001)and p-AKT(P＜0.01),but did not affect the protein levels of PI3K and AKT(P＞0.05).The above findings indicated that CMTM4 gene expression was down-regulated in cervical cancer,and CMTM4 overexpression inhibited cervical cancer cell proliferation and induced apoptosis by inhibiting the PI3K/AKT pathway.Therefore,CMTM4 may be used as a biological marker for screening cervical cancer.