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.

Acute symptomatic osteoporotic thoracolumbar compression fracture (ASOTLF) can lead to chronic low back pain, kyphosis deformity, pulmonary dysfunction, loss of mobility, and even life-threatening complications. Vertebral augmentation is currently the mainstream treatment method for this condition. In 2019, the Editorial Board of Chinese Journal of Trauma and the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association collaboratively led the development of Clinical guideline for vertebral augmentation for acute symptomatic osteoporotic thoracolumbar compression fractures. Six years later, with advances in clinical diagnosis and treatment techniques as well as accumulating evidence in related fields, the 2019 guideline requires updating. To this end, the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association, the Spinal Health Professional Committee of China Human Health Science and Technology Promotion Association, and the Minimally Invasive Orthopedics Professional Committee of Shaanxi Medical Doctor Association have organized experts in the field to develop the Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures ( version 2025) , based on the latest evidence-based medical researches. This guideline incorporates 3 recommendations retained from the 2019 version with updated strength of evidence, along with 12 new recommendations. It provides recommendations from six aspects of diagnosis, pain management, treatment option selection, prevention of postoperative complications, anti-osteoporosis therapy, and postoperative rehabilitation, aiming to provide a reference for standard treatment of vertebral augmentation for ASOTLF in hospitals at all levels.

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.

Objective To investigate the clinical characteristics and management strategies of spinal infarction(SCI)combined with hypoxic-ischemic encephalopathy(HIE).Methods We report a case of SCI induced by cardiopulmonary arrest in a patient admitted to the General Hospital of Southern Theater Command in June 2021.A review of the relevant literature published in PubMed and CNKI from January 2014 to March 2024,was conducted to summarize the etiology,features,and treatment approaches for SCI.Results The patient presented with clinical features of quadriplegia accompanied by paresthesia,lumbar and cervical pain with paresthesia,dysphagia,dysphonia,and urinary and fecal incontinence.Spinal MRI revealed abnormal signals in the anterior and lateral columns at the C2-T1 spinal level,with no enhancement observed in contrast-enhanced scan.The patient was diagnosed as SCI combined with HIE,and was treated with antiplatelet therapy and rehabilitation.Literature review revealed that SCI is a rare central nervous system disease with multiple causes,often related to aortic surgery or pathology,presenting with segmental sensory disturbances among other clinical manifestations.MRI plays a significant role in its diagnosis,and there is currently no specific effective treatment available.Conclusions SCI has a sudden onset and is often insidious,frequently accompanying other diseases,leading to a high risk of misdiagnosis.In this case,SCI was considered to be caused by low blood pressure and vertebral artery tenuity.Clinical manifestations include paraplegia at the lesion level along with back/neck pain or limb paresthesia.Diagnosis primarily relies on MRI imaging while treatment involves secondary stroke prevention measures,rehabilitation training,complication prevention strategies as well as hyperbaric oxygen therapy.

Objective To explore the effectiveness of drawing-based method in medical courses and their impact on students' learning habits,academic performance,and comprehensive competencies,in order to meet the demand for high-quality,interdisciplinary,and innovative talent,and provide theoretical support for integrating aesthetic education into medical training.Methods A questionnaire survey was conducted among medical students(n=310)at Dalian Medical University,covering the frequency of using drawing method and their effects on learning outcomes,innovation ability,and humanistic qualities.Data were analyzed using the Chi-square test and Fisher's exact test(P＜0.05).Results Totally 93.6％of students approved of using drawing method for learning medical courses,with 70.8％having developed a habit of drawing-based learning.Students with stronger drawing skills were more inclined to use drawing method and supported their application in teaching.The frequency of drawing-based learning was positively correlated with anatomy scores(P＜0.05).Students generally agreed that drawing method enhanced knowledge comprehension,learning interest,long-term memory,innovation ability,critical thinking,and humanistic qualities.However,students with weaker drawing skills perceived drawing method as potentially increasing learning burdens and being less efficient,but this perception significantly decreased with increased drawing frequency(P＜0.05).Conclusion Drawing methods are widely used in medical courses and effectively improve learning outcomes and comprehensive competencies.Drawing proficiency and frequency are key factors influencing students' acceptance and learning effectiveness.Future efforts should focus on promoting drawing method,strengthening students' drawing skills,and optimizing learning processes to deepen the integration of aesthetic education in medical training.

Aim To explore the mechanism of Jiawei Shaofu Zhuyu decoction in antagonizing endometriosis fibrosis by regulating mitophagy.Methods After the animal model was constructed,the syndrome was evalu-ated by general condition,organ water content and ther-mal imaging.The curative effect was evaluated by the weight of ectopic focus and the degree of adhesion.The pathological changes were compared using HE stai-ning,transmission electron microscopy,Masson and Sir-ius red staining.The expression of PINK1 and Parkin was detected by immunohistochemistry.The expression of mRNA and protein was determined by qPCR and Western blot,and the level of serum ROS was detected by ELISA.Results The autonomic activity of model mice was weakened,the water content of organs rose,and the temperature of limbs and lower abdomen was reduced by thermal imaging.HE staining showed obvi-ous hyperplasia of ectopic epithelium and glands.Transmission electron microscopy showed mitochondrial and endoplasmic reticulum structure damage,and nor-mal autophagy structure disappeared.Masson and Siri-us red staining showed increased collagen deposition;immunohistochemistry showed decreased expression of PINK1 and Parkin in ectopic foci.qPCR and Western blot showed that the expression of PINK1,Parkin,Bec-lin1,LC3 mRNA and protein in ectopic foci of model mice decreased,the expression of p62 mRNA and pro-tein increased,and serum ROS increased.The syn-drome performance of model mice was improved after the intervention of Jiawei Shaofu Zhuyu decoction;the inflammatory infiltration of ectopic foci was relieved,the morphology of mitochondria and endoplasmic retic-ulum was restored,and normal autophagy structure ap-peared.The degree of collagen deposition and fibrosis was reduced;the mRNA and protein expression of PINK1,Parkin,Beclin1 and LC3 increased.The ex-pression of p62 mRNA and protein decreased,and the level of ROS decreased.Conclusions Jiawei Shaofu Zhuyu decoction can improve the fibrosis of ectopic le-sions in mice with endometriosis of cold-dampness sta-sis syndrome,which may be related to the regulation of mitophagy.

Objective To analyze the imaging features of cerebral small vessel disease in patients with type 2 diabetes mellitus by multimodal MRI.Methods The clinical data of 160 patients with cerebral small vessel disease admitted to our hospital from January to December 2020 were retrospectively analyzed.According to whether they were complicated with type 2 diabetes mellitus,they were divided into the diabetic group and the non-diabetic group,with 80 cases in each group.Both groups underwent multimodal MRI scans.And the severity of lacunar infarction,the severity of subcortical and periventricular white matter lesions,white matter integral and cerebral microbleeds of patients in the two groups were compared.Results The severity of lacunar infarction(χ2=34.076,P=0.001),subcortical white matter lesions(χ2=25.000,P=0.001),periventricular white matter lesions(χ2=22.895,P=0.001)and white matter integral(t=12.370,P=0.001)of patients in the diabetic group were significantly higher than those in the non-diabetic group.No cerebral microbleeds were detected in either group of patients.Conclusion Patients with cerebral small vessel disease and type 2 diabetes mellitus show characteristic multimodal MRI changes.The increase in the number of lacunar infarction lesions and the aggravation of white matter lesions can be used as the characteristic imaging basis for the diagnosis of type 2 diabetes mellitus related cerebral small vessel disease.

Objective:To explore the effect of Lactobacillus reuteri on testicular injury in mice exposed to neonicotinoid insec-ticides(NNI).Methods:Fifteen C57BL/6 male mice were randomly divided into control group(CTRI.group),exposure group(NNI group)and Lactobacillus intervention group(NNI-L group).The mice in CTRL group were given 0.02ml/g of 0.5％carboxym-ethyl cellulose sodium solution by gavage for 14 days.The mice in NNI group were given 0.02 ml/g of NNI mixture by gavage for 14 days.The mice in NNI-L group were given 0.02 ml/g of NNI mixture by gavage and 5 × 108cfu/ml of Lactobacillus reuteri powder so-lution for 14 days.Then,the histomorphology and function of testicle were evaluated by hematoxylin-eosin staining,immunofluores-cence staining and RNA sequencing.Results:Compared with CTRL group,the thickness of testicular seminiferous epithelium in the NNI group was significantly thinner.And the decline in the number of spermatogenic cells and sperm was observed.And the expression of spermatogonial stem cell marker UCHL1 was down-regulated which was significantly improved in NNI-L group compared with the NNI group.The abnormal expressions of hormone and sperm methylation related genes in testis of NNI group were detected by RNA sequen-cing,with significant down-regulation being found in NPFF and IGF2.While the expression of HSD3B8 was significantly up-regulated.The abnormal expression of these genes could be significantly improved after oral administration of Lactobacillus reuteri.Conclusion:Testicular spermatogenesis and endocrine function can be damaged by NNI exposure.And oral administration of Lactoba-cillus reuteri protects testis from the adverse effects of NNI toxicity.

Nitrofurazone(NFZ)is an antibiotic that is used as a veterinary drug in aquaculture.NFZ abuse can lead to a series of environmental and health issues,making it crucial to establish a rapid and highly sensitive method for NFZ detection.In this study,platinum nanoparticle(PtNPs)-loaded zeolitic imidazolate framework(ZIF-8)was used as a precursor,and PtNPs functionalized nitrogen doped porous carbon(NC)was obtained through pyrolysis.Pt@NC was combined with multi-walled carbon nanotubes(MWCNTs)and cast onto a glassy carbon electrode(GCE)surface to construct an electroch-emical sensor.Electrochemical tests revealed that Pt@NC/WCNT/GCE exhibited an electrochemical active area of 0.066 cm2 and a heterogeneous electron transfer rate constant(k0)of 2.03×10-3 cm/s,which were higher than other materials.Compared with the electrodes modified by other materials,the NFZ generated the highest peak current of irreversible reduction peak on the Pt@NC/WCNT/GCE electrode.In comparison with Pt@ZIF-8/WCNT/GCE,after pyrolysis and carbonization treatment,the reduction current of NFZ increased by 2.19 times,and the reduction peak potential shifted positively by 19 mV simultaneously.When compared with NC/WCNT/GCE,the PtNPs in the composite material enhanced the NFZ current by 4.25 times.Additionally,the experimental conditions for detecting NFZ using the sensor were optimized,including the carbonization temperature of Pt@ZIF-8,ratio of Pt@NC to CNT,loading amount of the modified material,and electrolyte pH.Under the optimized conditions,the sensor demonstrated a linear detection range for NFZ of 0.20-240 μmol/L,a sensitivity of 9.995 μA/((μmol/L)?cm2)and a limit of detection(LOD)of 0.06 μmol/L.The sensor exhibited excellent anti-interference capability,good reproducibility,and stability,with spiked recoveries for NFZ in water samples ranging from 94.6%to 105.6%.This study provided a novel electrochemical sensing approach for NFZ detection.

Direct electrical stimulation of the human cortex can produce subjective visual sensations, yet these sensations are unstable. The underlying mechanisms may stem from differences in electrophysiological activity within the distributed network outside the stimulated site. To address this problem, we recruited 69 patients who experienced visual sensations during invasive electrical stimulation while intracranial electroencephalography (iEEG) data were recorded. We found significantly flattened power spectral slopes in distributed regions involving different brain networks and decreased integrated information during elicited visual sensations compared with the non-sensation condition. Further analysis based on minimum information partitions revealed that the reconfigured network interactions primarily involved the inferior frontal cortex, posterior superior temporal sulcus, and temporoparietal junction. The flattened power spectral slope in the inferior frontal gyrus was also correlated with integrated information. Taken together, this study indicates that the altered electrophysiological signatures provide insights into the neural mechanisms underlying subjective visual sensations.
Humans ; Male ; Female ; Adult ; Visual Perception/physiology* ; Electric Stimulation ; Middle Aged ; Young Adult ; Electrocorticography ; Electroencephalography ; Brain Mapping