The functional realization of proteins and other biological macromolecules depends on conformational dynamics and allosteric regulation, and elucidating their molecular mechanisms is an important foundation for understanding life processes. Molecular dynamics simulations are a powerful tool for investigating conformational evolution at the atomic level. However, traditional methods are limited by simulation timescales and high free-energy barriers, making it difficult to effectively capture rare conformations and their transition pathways. As a result, the development of enhanced sampling techniques has become key to overcoming this bottleneck. As a classical enhanced sampling technique, metadynamics suffers from several shortcomings, including strong dependence on collective variables and significant errors caused by bias potential accumulation. This article reviews three major improvement strategies. The first combines stochastic resetting with metadynamics, using trajectory-resetting mechanisms to improve sampling efficiency while avoiding the difficulty of optimizing collective variables. The second, SinkMeta, employs a “sinking” bias effect to enable efficient exploration of specific regions and paths. The third, OPES-based hybrid methods, improve the stability of free-energy estimation by optimizing the target distribution or the way the bias is constructed. These methods provide new ideas for characterizing free-energy landscapes and studying conformational transitions in complex biological systems, while also promoting the continued development of enhanced sampling methodologies.

Objective To retrospectively analyze the clinical risk factors and prognosis of perioperative myocardial injury(MINS)in non-cardiac surgery patients admitted to the intensive care unit(ICU).Methods A total of 478 postoperative patients admitted to the Department of Intensive Medicine,Minhang Hospital,Fudan University from Jan 2020 to Dec 2023 were selected.They were divided into MINS group(n=302)and normal group(n=176)based on whether myocardial injury occurred within 7 days after surgery.The differences in clinical characteristics between the two groups were compared,and risk factors for perioperative myocardial injury were identified.Risk factors for mortality in the MINS group were analyzed with 30-day mortality as the clinical endpoint.Results The prevalence of acute physiology and chronic health evaluation Ⅱ(Apache Ⅱ)score,coronary artery disease,and chronic kidney disease were all higher in the MINS group than those in the normal group,with statistically significant differences(P<0.05).The proportion of emergency surgeries,co-infection,and perioperative hypotension were significantly different between the MINS group and the normal group(P<0.05).Multivariate logistic regression analysis revealed that chronic kidney disease,emergency surgery,co-infection,and intraoperative and postoperative hypotension were risk factors for MINS occurrence.Prognostic analysis indicated that perioperative hypotension was a risk factor for 30-day mortality in MINS patients.Conclusion MINS is closely associated with patients'underlying conditions,timing of surgery,and perioperative hypotension status,and especially perioperative hypotension affects the final outcomes.

Objective To retrospectively analyze the clinical risk factors and prognosis of perioperative myocardial injury(MINS)in non-cardiac surgery patients admitted to the intensive care unit(ICU).Methods A total of 478 postoperative patients admitted to the Department of Intensive Medicine,Minhang Hospital,Fudan University from Jan 2020 to Dec 2023 were selected.They were divided into MINS group(n=302)and normal group(n=176)based on whether myocardial injury occurred within 7 days after surgery.The differences in clinical characteristics between the two groups were compared,and risk factors for perioperative myocardial injury were identified.Risk factors for mortality in the MINS group were analyzed with 30-day mortality as the clinical endpoint.Results The prevalence of acute physiology and chronic health evaluation Ⅱ(Apache Ⅱ)score,coronary artery disease,and chronic kidney disease were all higher in the MINS group than those in the normal group,with statistically significant differences(P<0.05).The proportion of emergency surgeries,co-infection,and perioperative hypotension were significantly different between the MINS group and the normal group(P<0.05).Multivariate logistic regression analysis revealed that chronic kidney disease,emergency surgery,co-infection,and intraoperative and postoperative hypotension were risk factors for MINS occurrence.Prognostic analysis indicated that perioperative hypotension was a risk factor for 30-day mortality in MINS patients.Conclusion MINS is closely associated with patients'underlying conditions,timing of surgery,and perioperative hypotension status,and especially perioperative hypotension affects the final outcomes.

Aim To investigate the role of triggering receptor expressed on myeloidcells 2(TREM2)in syn-aptic plasticity induced by cocaine addiction.Methods C57BL/6J mice and Trem2 knockout mice were uti-lized in this study to evaluate the alterations in postsyn-aptic density protein 95(PSD-95)and synapsin 1(SYN1)within the cortex and hippocampus of co-caine-addicted mice by using immunological tech-niques.Results HE staining and Nissl staining showed increased neuronal damage in the hippocampus and cortex of mice after cocaine addiction.The results of immunohistochemistry and fluorescence of PSD-95 and SYN1 were consistent with the expression trend of Western blot.In the wild type mouse model,the ex-pression level of PSD-95 in the hippocampus and cortex was lower than that in the saline group,and the ex-pression of SYN1 was higher than that in the saline group.In the knockout mouse model,the expression levels of PSD-95 and SYN1 in the hippocampus and cortex were significantly higher than those in the saline group after cocaine addiction.The expression levels of PSD-95 and SYN1 in the hippocampus and cortex of cocaine knockout mice were higher than those of co-caine wild type mice.Conclusion Cocaine addiction can change the synaptic plasticity,and TREM2 plays a regulatory role in the synaptic plasticity of hippocampus and cortex in mice with cocaine injury.TREM2 is ex-pected to be a new target for studying the mechanism of cocaine addiction.

Aim To investigate the effect of icariin(ICA)on chronic ulcerative colitis(UC)in mice.Methods Male SPF-grade C57BL/6J mice were ran-domly divided into the control group,model group,low-dose ICA group,and high-dose ICA group.Except for the control group,the rest of the mice were established as chronic UC models.Expressions of tight junction proteins,inflammatory factors,fibrosis markers,macro-phage markers,and MAPK signaling pathways in the colonic epithelium of each group were determined by Western blot,qPCR,immunohistochemistry;the degree of intestinal damage and fibrosis was detected by HE and Masson staining;the co-localization of different macrophage markers with related factors was examined by immunofluorescence.Results Treatment of ICA significantly improved the general condition of chronic UC mice,decreased the infiltration of M1-type macro-phages and the secretion of pro-inflammatory factors,inhibited the MAPK signaling pathway,reduced the co-localization expression of M1-type macrophages with the MAPK signaling pathway,and downregulated the infiltration of M2-type macrophages and the secretion of pro-fibrotic factors in the colon.Conclusion ICA mitigates the inflammatory damage and fibrosis of colon in chronic UC mice.

Objective To design an 8-channel gene analyzer to take the place of the widely used gene analyzer with problems in inconvenient consumable replacement and short storage time of electrophoresis polymer.Methods The 8-channel gene analyzer had its mechanical components composed of an automatic sample loading table,a polymer injection module,a high-voltage temperature control module,an optical module and an integrated U box,its electrical control system made up of a host computer(an embedded computer)and three slave computers(a sampling control board,a polymer injection control board and a high-voltage temperature control board).The automatic sample loading table involved in four motors and transmission systems for x,y,z directions and optical alignment,the transmission systems adopted mainly belt drive mode and the optical alignment motor had its threads with an anti-backlash structure;the polymer injuection module was manipulated by the polymer injection control board,and the polymer block was made of highly transparent acrylic material;the high-voltage temperature control module realized the regulation of electrophoresis voltage and the detection of electrophoresis current by the low-ripple precision high-voltage power supply,and controlled the temperature of the heating furnace by the proportional-integral-differential(PID)algorithm;the optical module consisted of an excitation module and a light-receiving module,which had the base of the reflector made of low expansion coefficient alloy material;the integrated U box had the electrophoresis polymer,capillary array,polymer block and anode buffer in a plastic housing;the host computer had the data acquisition software programmed with C# and C++,and the slave computers were controlled by STM32 SCM.Results The 8-channel gene analyzer had no significant differences with the widely used ABI3500 gene analyzer in resolution,precision accuracy and clinical results.Conclusion The 8-channel gene analyzer gains advantages in consumable replacement and storage time of electrophoresis polymer,and can meet the requirements for gene sequencing.[Chinese Medical Equipment Journal,2025,46(2):24-30]

Aim To investigate the effect of icariin(ICA)on chronic ulcerative colitis(UC)in mice.Methods Male SPF-grade C57BL/6J mice were ran-domly divided into the control group,model group,low-dose ICA group,and high-dose ICA group.Except for the control group,the rest of the mice were established as chronic UC models.Expressions of tight junction proteins,inflammatory factors,fibrosis markers,macro-phage markers,and MAPK signaling pathways in the colonic epithelium of each group were determined by Western blot,qPCR,immunohistochemistry;the degree of intestinal damage and fibrosis was detected by HE and Masson staining;the co-localization of different macrophage markers with related factors was examined by immunofluorescence.Results Treatment of ICA significantly improved the general condition of chronic UC mice,decreased the infiltration of M1-type macro-phages and the secretion of pro-inflammatory factors,inhibited the MAPK signaling pathway,reduced the co-localization expression of M1-type macrophages with the MAPK signaling pathway,and downregulated the infiltration of M2-type macrophages and the secretion of pro-fibrotic factors in the colon.Conclusion ICA mitigates the inflammatory damage and fibrosis of colon in chronic UC mice.

This consensus was developed by the Orthodontic Society of the Chinese Stomatological Association to provide a systematic, scientific, and practical guideline for informed consent in orthodontic care. Orthodontic treatment is typically lengthy, highly individualized, and involves multiple factors such as growth and development, occlusal function, and facial esthetics. Rapid technological advances and diverse risk profiles make the traditional reliance on orthodontist experience or institutional templates insufficient to ensure patients′ full understanding and autonomous decision-making. To address this, the expert panel conducted extensive reviews of domestic and international guidelines, analyzed representative dispute cases, and performed multicenter patient-clinician surveys. Using a multi-round Delphi method, the group established a standardized informed consent framework covering the initial consultation, treatment, and retention phases. The consensus emphasizes that informed consent is not only a fundamental legal and ethical requirement but also a key step in building trust, improving patient compliance, and enhancing treatment satisfaction. Orthodontists should clearly and comprehensively explain treatment plans, potential risks, uncertainties, and associated costs, while respecting the autonomy of patients or guardians, and maintain continuous communication and dynamic evaluation throughout the treatment process. The release of this consensus provides unified and authoritative guidance for clinical orthodontics, helping to standardize informed consent, enhance its transparency, safeguard patient rights, reduce medical risks, and promote high-quality, sustainable development of orthodontic practice.

Aim To investigate the role of triggering receptor expressed on myeloidcells 2(TREM2)in syn-aptic plasticity induced by cocaine addiction.Methods C57BL/6J mice and Trem2 knockout mice were uti-lized in this study to evaluate the alterations in postsyn-aptic density protein 95(PSD-95)and synapsin 1(SYN1)within the cortex and hippocampus of co-caine-addicted mice by using immunological tech-niques.Results HE staining and Nissl staining showed increased neuronal damage in the hippocampus and cortex of mice after cocaine addiction.The results of immunohistochemistry and fluorescence of PSD-95 and SYN1 were consistent with the expression trend of Western blot.In the wild type mouse model,the ex-pression level of PSD-95 in the hippocampus and cortex was lower than that in the saline group,and the ex-pression of SYN1 was higher than that in the saline group.In the knockout mouse model,the expression levels of PSD-95 and SYN1 in the hippocampus and cortex were significantly higher than those in the saline group after cocaine addiction.The expression levels of PSD-95 and SYN1 in the hippocampus and cortex of cocaine knockout mice were higher than those of co-caine wild type mice.Conclusion Cocaine addiction can change the synaptic plasticity,and TREM2 plays a regulatory role in the synaptic plasticity of hippocampus and cortex in mice with cocaine injury.TREM2 is ex-pected to be a new target for studying the mechanism of cocaine addiction.

This study aims to investigate the effect of Chaijin Jieyu Anshen Formula on the neuroinflammation of rats with insomnia complicated with depression through the regulation of triggering receptor expressed on myeloid cells 2(TREM2)/complement protein C1q signaling pathway. Rats were randomly divided into a normal group, a model group, a positive drug group, as well as a high, medium, and low-dose groups of Chaijin Jieyu Anshen Formula, with 10 rats in each group. Except for the normal group, the other groups were injected with p-chlorophenylalanine and exposed to chronic unpredictable mild stress to establish the rat model of insomnia complicated with depression. The sucrose preference experiment, open field experiment, and water maze test were performed to evaluate the depression in rats. Enzyme-linked immunosorbent assay was employed to detect serum 5-hydroxytryptamine(5-HT), dopamine(DA), and norepinephrine(NE) levels. Hematoxylin and eosin staining and Nissl staining were used to observe the damage in nucleus accumbens neurons. Western blot and immunofluorescence were performed to detect TREM2, C1q, postsynaptic density 95(PSD-95), and synaptophysin 1(SYN1) expressions in rat nucleus accumbens, respectively. Golgi-Cox staining was utilized to observe the synaptic spine density of nucleus accumbens neurons. The results show that, compared with the model group, Chaijin Jieyu Anshen Formula can significantly increase the sucrose preference as well as the distance and number of voluntary activities, shorten the immobility time in forced swimming test and the successful incubation period of positioning navigation, and prolong the stay time of space exploration in the target quadrant test. The serum 5-HT, DA, and NE contents in the model group are significantly lower than those in the normal group, with the above contents significantly increased after the intervention of Chaijin Jieyu Anshen Formula. In addition, Chaijin Jieyu Anshen Formula can alleviate pathological damages such as swelling and loose arrangement of tissue cells in the nucleus accumbens, while increasing the Nissl body numbers. Chaijin Jieyu Anshen Formula can improve synaptic damage in the nucleus accumbens and increase the synaptic spine density. Compared to the normal group, the expression of C1q protein was significantly higher in the model group, while the expression of TREM2 protein was significantly lower. Compared to the model group, the intervention with Chaijin Jieyu Anshen Formula significantly downregulated the expression of C1q protein and significantly upregulated the expression of TREM2. Compared with the model group, the PSD-95 and SYN1 fluorescence intensity is significantly increased in the groups receiving different doses of Chaijin Jieyu Anshen Formula. In summary, Chaijin Jieyu Anshen Formula can reduce the C1q protein expression, relieve the TREM2 inhibition, and promote the synapse-related proteins PSD-95 and SNY1 expression. Chaijin Jieyu Anshen Formula improves synaptic injury of the nucleus accumbens neurons, thereby treating insomnia complicated with depression.
Animals ; Male ; Rats ; Nucleus Accumbens/metabolism* ; Drugs, Chinese Herbal/administration & dosage* ; Depression/complications* ; Membrane Glycoproteins/genetics* ; Rats, Sprague-Dawley ; Sleep Initiation and Maintenance Disorders/complications* ; Neurons/metabolism* ; Receptors, Immunologic/genetics* ; Signal Transduction/drug effects* ; Synapses/metabolism*