BACKGROUND:In recent studies,hydrogel loaded with exosomes has attracted wide attention as an emerging therapeutic strategy in the field of tissue engineering and regenerative medicine,and is considered as a promising means for the treatment of nerve regeneration and wound healing.OBJECTIVE:To review the application of hydrogel loaded with exosomes in nerve regeneration and wound healing and to provide reference and guidance for future research and clinical application.METHODS:The first author used a computer in May 2024 to retrieve the relevant literature published from January 2000 to May 2024 on PubMed and CNKI,searching for"exosome,hydrogel,nerve,nerve regeneration,wound,wound healing"in Chinese and English,eventually incorporating 66 papers for analysis.RESULTS AND CONCLUSION:(1)Hydrogel loaded with exosomes provides a promising path for nerve injury repair by exerting anti-inflammatory and anti-oxidation,stimulating axon growth and myelin regeneration.(2)Exosome-loaded hydrogel suppresses the level of inflammation and oxidative stress,accelerates the proliferation and migration of skin cells,collagen expression,and promotes blood vessel formation,significantly accelerates the wound healing process,and improves the healing quality.(3)The role of hydrogel loaded with exosomes in nerve regeneration and wound repair is still limited to cell and animal experiments,and does not involve clinical practice.In the future,more mechanistic studies,safety evaluation,and supplementary related clinical trials are still needed in the future.

BACKGROUND:In recent studies,hydrogel loaded with exosomes has attracted wide attention as an emerging therapeutic strategy in the field of tissue engineering and regenerative medicine,and is considered as a promising means for the treatment of nerve regeneration and wound healing.OBJECTIVE:To review the application of hydrogel loaded with exosomes in nerve regeneration and wound healing and to provide reference and guidance for future research and clinical application.METHODS:The first author used a computer in May 2024 to retrieve the relevant literature published from January 2000 to May 2024 on PubMed and CNKI,searching for"exosome,hydrogel,nerve,nerve regeneration,wound,wound healing"in Chinese and English,eventually incorporating 66 papers for analysis.RESULTS AND CONCLUSION:(1)Hydrogel loaded with exosomes provides a promising path for nerve injury repair by exerting anti-inflammatory and anti-oxidation,stimulating axon growth and myelin regeneration.(2)Exosome-loaded hydrogel suppresses the level of inflammation and oxidative stress,accelerates the proliferation and migration of skin cells,collagen expression,and promotes blood vessel formation,significantly accelerates the wound healing process,and improves the healing quality.(3)The role of hydrogel loaded with exosomes in nerve regeneration and wound repair is still limited to cell and animal experiments,and does not involve clinical practice.In the future,more mechanistic studies,safety evaluation,and supplementary related clinical trials are still needed in the future.

Objective:To explore eye movement characteristics in newly diagnosed, drug-naive Parkinson′s disease (PD) patients and their correlation with motor and non-motor symptoms.Methods:Seventy-five newly diagnosed, drug-naive PD patients and 46 healthy controls (HCs) were included in this cross-sectional study. Patients were recruited from the Department of Neurology, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine from November 2017 to December 2021, while HCs were recruited from the local community during the same period. For PD patients, motor severity was measured with the modified Hoehn and Yahr stage, Movement Disorder Society Unified Parkinson′s Disease Rating Scale part Ⅲ and the Freezing of Gait questionnaire. Non-motor symptoms were evaluated by serial scales such as Non-Motor Symptoms Questionnaire, 16-item odor identification test from Sniffin Sticks, 17-item Hamilton Rating Scale for Depression, Chinese version of Mini-Mental State Examination, Montreal Cognitive Assessment Basic and REM Behavior Disorder Screening Questionnaire. All subjects underwent oculomotor test including pro-saccade task and smooth pursuit eye movement (SPEM) task in the horizontal direction via videonystagmography. Visually guided saccade latency, saccadic accuracy and gain in SPEM at three frequencies (0.1, 0.2, 0.4 Hz) of the horizontal axis were compared between the 2 groups. The association between key oculomotor parameters and clinical phenotypes was explored in PD patients. The receiver operating characteristic (ROC) analyses of eye movement parameters as independent factors were also performed for detecting PD from HCs, then combining the saccadic latency, saccadic accuracy and the most significant SPEM gain (0.4 Hz) as the model to distinguish PD from HCs.Results:Relative to HCs, newly diagnosed, drug-naive PD patients showed prolonged saccadic latency [(210.4±41.3) ms vs (191.3±18.9) ms, t=-3.445, P=0.001] and decreased saccadic accuracy (88.4%±6.8% vs 92.2%±6.1%, t=3.064, P=0.003). SPEM gain in PD was uniformly reduced at each frequency(0.1 Hz: 0.68±0.15 vs 0.74±0.14, t=2.261, P=0.026; 0.2 Hz: 0.72±0.16 vs 0.79±0.16, t=2.704, P=0.008; 0.4 Hz: 0.67±0.19 vs 0.78±0.19, t=2.937, P=0.004). The ROC analyses of saccade latency, saccadic accuracy and gain in SPEM at 0.1, 0.2, 0.4 Hz as independent factors for detecting PD from HCs showed that the area under the curve (AUC) of each parameter was lower than 0.7: the AUC of saccade latency was 0.641 ( P=0.010), the AUC of saccadic accuracy was 0.681 ( P=0.001), the AUC of gain in SPEM at 0.1 Hz was 0.616 ( P=0.032), at 0.2 Hz was 0.652 ( P=0.005), at 0.4 Hz was 0.660 ( P=0.003). Combining the saccadic latency, saccadic accuracy and the most significant SPEM gain (0.4 Hz) revealed that the model could significantly distinguish PD from HCs with an 80.4% sensitivity and a 73.3% specificity (AUC=0.780, P<0.001). Prolonged saccadic latency was correlated with long disease duration ( β=0.334, 95% CI 0.014-0.654, P=0.041), whereas decreased SPEM gain was associated with severe motor symptoms in newly diagnosed drug-naive PD patients (0.1 Hz: β=-0.004, 95% CI -0.008--0.001, P=0.036; 0.4 Hz: β=-0.006, 95% CI -0.011--0.001, P=0.012). Conclusions:Ocular movements are impaired in newly diagnosed, drug-naive PD patients. These changes could be indicators for disease progression in PD.

Objective To investigate the situation and distribution of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) infection in volunteer blood donors during SARS epidemic phase and non-SARS epidemic phase in Guangzhou and provide scientific basis for developing preventive strategies. Methods Blood samples from volunteer donors were tested for SARS-CoV Ab by ELISA,and samples from 31 plasma donors recovered from SARS were tested as control. Donors with positive SARS-CoV Ab were further tested for SARS-CoV RNA by fluorescent polymerase chain reaction. Standardized questionnaires were adopted to conduct investigation by telephone on 20 donors with positive SARS-CoV Ab. Results SARS-CoV Ab was positive in 56 of 6120 volunteer blood donors and in 30 of 31 plasma donors recovered from SARS. The positive rates of SARS-CoV Ab were 0.92% and 96.77% respectively. In volunteer blood donors of SARS epidemic phase and non-SARS epidemic phase, the positive rates of SARS-CoV Ab were 0.91% and 0.92% respectively, and there was no significant difference between them. The mean S/CO and the titer of SARS-CoV Ab were 2.34 and ≤1∶2 respectively in the 56 volunteer blood donors, significantly lower than those of the 30 plasma donors recovered from SARS (S/CO 14.8,titer ≤1∶32). All donors with positive SARS-CoV Ab were negative for SARS-CoV RNA. Telephone consultation of 20 random blood donors with positive SARS-CoV Ab found that they were in good health and had not have close contact with SARS patients. Conclusion There is a low positive rate of SARS-CoV Ab among random blood donors in Guangzhou. Further studies are needed to find out whether those donors have been infected by SARS. It is also possible that those reactions were false positive, which might be caused by cross reactions. It is suggested that the present measures of SARS prevention could ensure blood safety.