Medical artificial intelligence （AI） is a new type of application formed by the combination of machine learning， computer vision， natural language processing， and other technologies with clinical medical treatment. With the continuous iteration and development of relevant technologies， medical AI has shown great potential in improving the efficiency of diagnosis and treatment， and service quality， but it also increases the possibility of triggering ethical issues. Ethical issues resulting from the clinical application of medical AI were analyzed， including the lack of algorithmic interpretability and transparency of medical AI， leading to information asymmetry and cognitive discrepancies； the concerning status of security and privacy protection of medical data； and the complex and unclear division of responsibilities due to the collaborative participation of multiple subjects in the clinical application of medical AI， resulting in increased difficulty in the identification of medical accidents and clarification of responsibilities. The paper proposed the principles of not harming patients’ interests， physician’s subjectivity， fairness and inclusiveness， and rapid response. It also explored the strategies and implementation paths for responding to the ethical issues of medical AI from multiple perspectives， including standardizing the environment and processes， clarifying responsibility attribution， continuously assessing the impact of data protection， guaranteeing data security， ensuring model transparency and interpretability， carrying out multi-subject collaboration， as well as the principles of being driven by ethical values and adhering to the “human health-centeredness.” It aimed to provide guidance for the healthy development of medical AI， ensuring technological progress while effectively managing and mitigating accompanying ethical risks， thereby promoting the benign development of medical AI technology and better serving the healthcare industry and patients.

ObjectiveTo investigate the effects of Dihuang Yinzi on the cognitive function in the mouse model of learning and memory impairments induced by scopolamine （SCOP） and explore the treatment mechanism. MethodsA mouse model of learning and memory impairment was induced by intraperitoneal injection of SCOP. Sixty male C57BL/6J mice were randomized into six groups： control （0.9% NaCl， n=10）， model （SCOP 1 mg·kg^-1·d^-1， n=10）， low-， medium-， and high-dose Dihuang Yinzi （SCOP 1 mg·kg^-1·d^-1 + Dihuang Yinzi 5.5， 11.0， and 22.0 g·kg^-1·d^-1， n=10）， and donepezil （SCOP 1 mg·kg^-1·d^-1 + donepezil 0.84 mg·kg^-1·d^-1， n=10）. Mice were administrated with corresponding drugs for 6 weeks. Modeling started in the 4th week， and mice in other groups except the control group were injected with SCOP intraperitoneally 40 min after daily gavage. Behavioral testing began in the 5th week， 30 min after modeling each day. The Morris water maze and novel object recognition tests were carried out to evaluate the spatial learning and memory function of mice. Nissl staining was employed to observe the survival of neurons and Nissl bodies in the hippocampal CA1 region. Western blot was employed to determine the protein levels of silent information regulator 2 （SIRT2）， α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid （AMPA） receptor 1 （GluA1）， protein kinase A （PKA）， cAMP response element-binding protein （CREB）， phosphorylated-CREB （p-CREB）， postsynaptic density protein 95 （PSD95）， growth-associated protein-43 （GAP-43）， and synaptophysin （SYN） in the hippocampus. Immunofluorescence was used to detect the expression of doublecortin （DCX） in the hippocampal dentate gyrus （DG） region. ResultsCompared with the control group， the model group showed impaired learning and memory （P<0.01）， obvious neuronal damage in the hippocampal CA1 region， a reduction in neuron survival （P<0.01）， a decrease in DCX expression in the hippocampal DG region （P<0.01）， down-regulated proteins levels of GluA1， PKA， p-CREB/CREB， PSD95， SYN， and GAP-43 in the hippocampal tissue （P<0.05， P<0.01）， and an up-regulated protein level of SIRT2 （P<0.01）. Compared with the model group， the medium- and high-dose Dihuang Yinzi groups and the donepezil group showed improvements in learning and memory （P<0.05， P<0.01）， while the low-， medium-， and high-dose Dihuang Yinzi groups and the donepezil group had increased neuron survival （P<0.05， P<0.01）. The medium-dose Dihuang Yinzi group and the donepezil group showed increased DCX expression （P<0.05， P<0.01）. The medium- and high-dose Dihuang Yinzi groups and the donepezil group showed up-regulation in the protein levels of GluA1， PKA， p-CREB/CREB， PSD95， SYN， and GAP-43 （P<0.05， P<0.01） and down-regulation in the protein level of SIRT2 （P<0.01）. ConclusionDihuang Yinzi can improve the cognitive function in the mouse model of learning and memory impairments induced by SCOP by inhibiting the upregulation of SIRT2， activating the PKA/CREB signaling pathway， improving synaptic plasticity， and reducing hippocampal neuronal damage.

Alzheimer’s disease (AD) is a central neurodegenerative disease characterized by progressive cognitive decline and memory impairment in clinical. Currently, there are no effective treatments for AD. In recent years, a variety of therapeutic approaches from different perspectives have been explored to treat AD. Although the drug therapies targeted at the clearance of amyloid β-protein (Aβ) had made a breakthrough in clinical trials, there were associated with adverse events. Neuroinflammation plays a crucial role in the onset and progression of AD. Continuous neuroinflammatory was considered to be the third major pathological feature of AD, which could promote the formation of extracellular amyloid plaques and intracellular neurofibrillary tangles. At the same time, these toxic substances could accelerate the development of neuroinflammation, form a vicious cycle, and exacerbate disease progression. Reducing neuroinflammation could break the feedback loop pattern between neuroinflammation, Aβ plaque deposition and Tau tangles, which might be an effective therapeutic strategy for treating AD. Traditional Chinese herbs such as Polygonum multiflorum and Curcuma were utilized in the treatment of AD due to their ability to mitigate neuroinflammation. Non-steroidal anti-inflammatory drugs such as ibuprofen and indomethacin had been shown to reduce the level of inflammasomes in the body, and taking these drugs was associated with a low incidence of AD. Biosynthetic nanomaterials loaded with oxytocin were demonstrated to have the capability to anti-inflammatory and penetrate the blood-brain barrier effectively, and they played an anti-inflammatory role via sustained-releasing oxytocin in the brain. Transplantation of mesenchymal stem cells could reduce neuroinflammation and inhibit the activation of microglia. The secretion of mesenchymal stem cells could not only improve neuroinflammation, but also exert a multi-target comprehensive therapeutic effect, making it potentially more suitable for the treatment of AD. Enhancing the level of TREM2 in microglial cells using gene editing technologies, or application of TREM2 antibodies such as Ab-T1, hT2AB could improve microglial cell function and reduce the level of neuroinflammation, which might be a potential treatment for AD. Probiotic therapy, fecal flora transplantation, antibiotic therapy, and dietary intervention could reshape the composition of the gut microbiota and alleviate neuroinflammation through the gut-brain axis. However, the drugs of sodium oligomannose remain controversial. Both exercise intervention and electromagnetic intervention had the potential to attenuate neuroinflammation, thereby delaying AD process. This article focuses on the role of drug therapy, gene therapy, stem cell therapy, gut microbiota therapy, exercise intervention, and brain stimulation in improving neuroinflammation in recent years, aiming to provide a novel insight for the treatment of AD by intervening neuroinflammation in the future.

[摘 要] 免疫细胞介导的药物递送系统是以免疫细胞为载体，利用细胞固有的趋化作用将治疗药物靶向递送至特定病灶部位，因其具有优异的生物相容性、低免疫原性、组织特异性归巢及易穿过生物屏障等多重优势，已成为药物递送和疾病治疗的重要手段。本文系统论述免疫细胞的载药策略和单核细胞、中性粒细胞、间充质干细胞和树突状细胞等作为载体细胞的生物学特性、主要优缺点，以及应用于肿瘤治疗的最新研究进展，为深入研究免疫细胞介导的药物递送系统和临床转化提供重要参考。

BACKGROUND:Exercise as a form of active rehabilitation can improve the dysfunction caused by peripheral nerve injury,and different exercise modalities target different lesion sites and recovery mechanisms. OBJECTIVE:To comprehensively analyze the application and mechanisms of different exercise modalities in functional recovery from peripheral nerve injury. METHODS:A computerized search was conducted in PubMed and CNKI databases for relevant literature published before January 2024.The search terms used were"peripheral nerve injury,spinal cord,exercise,cerebral cortex,muscle atrophy,mirror therapy,blood flow restriction training"in both English and Chinese.Finally,77 articles were included for review. RESULTS AND CONCLUSION:Peripheral nerve injury can cause systemic pathological changes such as skeletal muscle atrophy,corresponding spinal cord segmental lesions,and sensorimotor cortex remodeling.Aerobic exercise can improve dysfunction by enhancing the immune response,promoting glial cell polarization,and promoting the release of nerve growth factor.Blood flow restriction exercise can regulate the secretion of muscle growth factor,promote muscle growth and enhance muscle strength.Mirror movement has a good effect in activating the cerebral cortex and reducing cortical remodeling.Different exercise modalities have potential benefits in functional recovery after peripheral nerve injury;however,there are still some problems and challenges,such as the choice of exercise modalities,the control of exercise intensity and frequency,and the detailed analysis of mechanisms.

ObjectiveTo study the mechanism of Huanglian Jiedutang （HLJDT） in treating mice with atherosclerosis （AS） by improving ferroptosis. MethodsA total of 10 SPF C57BL/6J mice were selected as a normal group， and 50 ApoE^-/- mice were randomly divided into five groups： model group， low-dose group of HLJDT， medium-dose group of HLJDT， high-dose group of HLJDT， and atorvastatin （ATV） group. ApoE^-/- mice were fed a high-fat diet for eight weeks to establish the AS model， and at the 9th week， they were given normal saline， low， medium， and high doses of HLJDT （3.9， 7.8， 15.6 g·kg^-1·d^-1）， and atorvastatin calcium tablets （0.01 g·kg^-1·d^-1）， respectively， for a total of eight weeks. The formation of aortic plaque in mice was observed by gross oil red O staining and Masson staining. The levels of total cholesterol （TC）， low-density lipoprotein cholesterol （LDL-C）， triglyceride （TG）， and high-density lipoprotein cholesterol （HDL-C） in blood fat were measured by the automatic biochemical analyzer， and the mitochondrial structure of the aorta was observed by transmission electron microscopy. The content of serum superoxide dismutase （SOD） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. The content of reduced glutathione （GSH） in serum was detected by the microplate method， and that of malondialdehyde （MDA） in serum was detected by the TBA method. The protein expression of nuclear factor E₂-associated factor 2 （Nrf2）/glutathione peroxidase 4 （GPX4） signaling pathway was detected by Western blot. ResultsCompared with those of the normal group， the contents of TC， LDL-C， TG， HDL-C， and MDA in the serum and the aortic vascular plaque deposition of the model group were significantly increased （P<0.01）， while the expression levels of SOD and GSH in serum， as well as Nrf2， solute carrier family 7 member 11 （SLC7A11）， and GPX4 in aorta were significantly decreased （P<0.01）. Mice in the model group appeared mitochondrial fragmentation and vacuolation in the aorta， volume atrophy， mitochondrial crista reduction， or a loose and disorganized form. Compared with those in the model group， the aortic vascular plaque deposition was significantly decreased in the low-dose， medium-dose， and high-dose groups of HLJDT and ATV group， and the contents of serum TC， LDL-C， TG， and MDA in serum were significantly decreased （P<0.05， P<0.01）. The contents of serum SOD and GSH and the expression levels of Nrf2， SLC7A11， and GPX4 in the aorta were increased （P<0.05， P<0.01）， and the symptoms of aortic mitochondrial vacuolation were alleviated. The number of cristae was increased， and they were ordered neatly. ConclusionHLJDT can reduce aortic vascular plaque deposition， decrease blood lipid and MDA expression， increase SOD and GSH expression， and ameliorate the pathological changes of ferroptosis， the mechanism of which is related to the Nrf2/GPX4 signaling pathway.

Background: In acute and chronic renal inflammatory diseases, the activation of inflammatory cells is involved in the defect of erythropoietin (EPO) production. Ras guanine nucleotide-releasing protein-4 (RasGRP4) promotes renal inflammatory injury in type 2 diabetes mellitus (T2DM). Our study aimed to investigate the role and mechanism of RasGRP4 in the production of renal EPO in diabetes. Methods: The degree of tissue injury was observed by pathological staining. Inflammatory cell infiltration was analyzed by immunohistochemical staining. Serum EPO levels were detected by enzyme-linked immunosorbent assay, and EPO production and renal interstitial fibrosis were analyzed by immunofluorescence. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of key inflammatory factors and the activation of signaling pathways. In vitro, the interaction between peripheral blood mononuclear cells (PBMCs) and C3H10T1/2 cells was investigated via cell coculture experiments. Results: RasGRP4 decreased the expression of hypoxia-inducible factor 2-alpha (HIF2A) via the ubiquitination–proteasome degradation pathway and promoted myofibroblastic transformation by activating critical inflammatory pathways, consequently reducing the production of EPO in T2DM mice. Conclusion RasGRP4 participates in the production of renal EPO in diabetic mice by affecting the secretion of proinflammatory cytokines in PBMCs, degrading HIF2A, and promoting the myofibroblastic transformation of C3H10T1/2 cells.

As the biggest tissue of human body, skin is the first barrier of resisting external aggression. Collagen is one of important parts of the skin, which could not only affect the aesthetics of skin, but also influence the health and normal function of skin. It is the great significance to find ways that could inhibit the loss of collagen. The mechanisms of the collagen degradation in skin are complex and multifaceted. Natural bioactive products have unique advantages in treating the loss of collagen, which have multi-targets and mechanisms. In this review, the mechanisms of skin collagen degradation are discussed, and the research progress of natural bioactive products in resisting skin aging through promoting collagen synthesis are reviewed, in order to provide references for futural research.

Background When live working line operators engage in upper limb operations, working for a long time with raising arms and the exposure to adverse ergonomic factors tend to increase muscle load, cause fatigue accumulation, and increase the risk of work-related musculoskeletal disorders (WMSDs). Objective To analyze work posture and associated muscle fatigue during executing breaking/connecting contact terminal, and identify adverse ergonomic factors of the work process. Methods This study recruited 10 volunteers to perform breaking/connecting contact terminal simulation. At a distance of 4.5, 3.5, and 2.5 m from the body to the wire, each performed the task 5 times. Visual 3D was used to analyze the kinematic data from motion capture. The surface electromyography (sEMG) signals of the deltoid, biceps, triceps, and brachioradialis were recorded during the simulation and analyzed for muscle fatigue using root mean square (RMS), median frequency (MF), and jointed EMG amplitude and spectrum analysis (JASA). After completion of each task, Borg scale was used to query the volunteers of their subjective fatigue. A 2-min rest was required between each distance. Results The kinematic data from motion capture showed that in the entire process of the task, the right upper limb was higher when lifting, with the right shoulder joint maintaining flexion and fluctuating periodically between abduction and adduction, external and internal rotation, the right elbow joint maintaining flexion and supination. The frequency of task cycle showed a significant effect on the Borg scale scores (P<0.001, partial \begin{document}$ {\eta }^{2} $\end{document}=0.464); the distance showed no significant effect on the Borg scale scores (P>0.05, partial \begin{document}$ {\eta }^{2} $\end{document}=0.002); their interaction effect was not significant (P>0.05, partial \begin{document}$ {\eta }^{2} $\end{document}=0.020). The results of the sEMG signals showed that at a distance of 4.5 m, the volunteers had the highest percentages of maximal voluntary electrical activation (MVE%) in the deltoid and right brachioradialis and the lowest MF values in the deltoid and left brachioradialis after completing 5 task cycles. The results of JASA showed that fatigue was observed in brachioradialis and deltoid after completing 5 task cycles at a distance of 4.5 m, the right deltoid and right brachioradialis at a distance of 3.5 m, in the brachioradialis, deltoid, and left bicep at a distance of 2.5 m. Conclusion The subjective fatigue of workers who engaged in breaking/connecting contact terminal elevates with more repetitive operations. Based on the sEMG and motion capture analysis, it can be found that improper distance between the workers and the target work area can increase the burden from poor posture and improper use of work equipment, and lead to muscle fatigue; the deltoid and brachioradialis are the key muscles of fatigue in this type of operation; changing the angle of the elbow joint and the shoulder joint during the process of the operation can affect the deltoid and brachioradialis exertion and loading.

Background Power grid is an important component of the national infrastructure. The occupational health issues among the workers in this industry are attracting great concern nationwide. Objective To investigate the prevalence of work-related musculoskeletal disorders (WMSDs) in neck and shoulder among the power distribution workers of power supply enterprises, and analyze the related influencing factors. Method In April 2023, a total of 1244 workers in 50 municipal power supply bureaus were randomly selected from the three provinces under China Southern Power Grid using cluster sampling method. The questionnaire used in the study was based on a revised Musculoskeletal Disorders Questionnaire and added ergonomic load of upper limb work. \begin{document}$ {\chi }^{2} $\end{document} test and logistic regression model were used to explore the influencing factors of neck pain and shoulder pain among the subjects. Results A total of 1244 valid questionnaires were recovered and the effective recovery rate was 90.87%(1244/1369). The positive rates of neck pain and shoulder pain were 45.5% (566 cases) and 36.3% (452 cases) respectively. The logistic regression analysis results showed that more than 20 years working age (OR=2.27, 95%CI: 1.39, 3.96; OR=2.56, 95%CI: 1.53, 4.26), often (OR=2.08, 95%CI: 1.35, 3.20; OR=2.40, 95%CI: 1.50, 3.58)/quite often (OR=2.96, 95%CI: 1.73, 5.04; OR=2.72, 95%CI: 1.49, 4.94) maintaining a forced posture, and working immediately after break (OR=1.72, 95%CI: 1.04, 2.85; OR=2.14, 95%CI: 1.19, 3.88) were associated with a higher positive rate of neck pain and shoulder pain respectively. Feeling sufficient rest (OR=0.61, 95%CI: 0.47, 0.80; OR=0.63, 95%CI: 0.50, 0.83) and opportunity to decide when to take breaks (OR=0.72, 95%CI: 0.53, 0.98; OR=0.62, 95%CI: 0.41, 0.93) were associated with a lower positive rate of neck pain and shoulder pain respectively. Conclusion The positive rates of neck pain and shoulder pain are high among power distribution workers. The main influencing factors included long working age, quite often maintaining a forced posture, and working immediately after break.