BACKGROUND:Polyurethane materials,with their outstanding physicochemical properties,present extensive opportunities in the realm of biomedical engineering.Biomimetic design and functional modification of polyurethane nerve conduits are expected to further address the challenges of nerve regeneration and repair.OBJECTIVE:To review the current status and advancements in the application of polyurethane-based nerve conduits in the field of peripheral nerve repair.METHODS:The Chinese and English search terms consisted of"polyurethane,PU,polyurethane material,polyurethane biomaterials,nerve regeneration,peripheral nerve injury,nerve repair,nerve scaffold,nerve guidance conduit,nerve conduits."The search was conducted in databases such as PubMed,Web of Science,CNKI(China National Knowledge Infrastructure),and WanFang for articles published from 2014 to 2024.Finally,61 articles were included in the review.RESULTS AND CONCLUSION:Biomimetic composition is an effective strategy for enhancing the biological activity of polyurethane nerve conduits.Through structural biomimicry,polyurethane nerve conduits can be optimized to provide biological guidance cues for neural tissue regeneration.The biomechanically biomimetic polyurethane nerve conduits are likely to play a significant role in immune modulation and the promotion of axonal growth.By optimizing the conductive microenvironment of polyurethane materials,the reconstruction of neural electrical signal pathways can be facilitated.Polyurethane nerve conduits can serve as drug carriers,exerting anti-inflammatory and neuroprotective effects.Although the combined application of multiple design strategies can improve various aspects of damaged nerve function,the complex structure and dynamically changing pathophysiological microenvironment of nerves mean that nerve conduit design strategies still require refinement.Future advancements and innovations in nerve biomimetic design strategies hold promise for providing new insights and opportunities in the field of neural tissue engineering.

BACKGROUND:Polyurethane materials,with their outstanding physicochemical properties,present extensive opportunities in the realm of biomedical engineering.Biomimetic design and functional modification of polyurethane nerve conduits are expected to further address the challenges of nerve regeneration and repair.OBJECTIVE:To review the current status and advancements in the application of polyurethane-based nerve conduits in the field of peripheral nerve repair.METHODS:The Chinese and English search terms consisted of"polyurethane,PU,polyurethane material,polyurethane biomaterials,nerve regeneration,peripheral nerve injury,nerve repair,nerve scaffold,nerve guidance conduit,nerve conduits."The search was conducted in databases such as PubMed,Web of Science,CNKI(China National Knowledge Infrastructure),and WanFang for articles published from 2014 to 2024.Finally,61 articles were included in the review.RESULTS AND CONCLUSION:Biomimetic composition is an effective strategy for enhancing the biological activity of polyurethane nerve conduits.Through structural biomimicry,polyurethane nerve conduits can be optimized to provide biological guidance cues for neural tissue regeneration.The biomechanically biomimetic polyurethane nerve conduits are likely to play a significant role in immune modulation and the promotion of axonal growth.By optimizing the conductive microenvironment of polyurethane materials,the reconstruction of neural electrical signal pathways can be facilitated.Polyurethane nerve conduits can serve as drug carriers,exerting anti-inflammatory and neuroprotective effects.Although the combined application of multiple design strategies can improve various aspects of damaged nerve function,the complex structure and dynamically changing pathophysiological microenvironment of nerves mean that nerve conduit design strategies still require refinement.Future advancements and innovations in nerve biomimetic design strategies hold promise for providing new insights and opportunities in the field of neural tissue engineering.

Objective This study aimed to investigate the therapeutic efficacy of Sanjie Quban recipe in a keloid nude mice model and its impact on transforming growth factor-β 1(TGF-β1).Methods Keloid tissue after surgical resection was subcutaneously transplanted into the backs of healthy SPF BALB/C female nude mice,aged 6～8 weeks,and a keloid nude mice model was thus established.The mice were randomly divided into three groups,the Sanjie Quban recipe group,the Asiaticoside tablet group and the control gnup,with five in each group.They were respectively treated with Sanjie Quban recipe,Asiaticoside tablets,or sterile pure water.After 28 days of continuous gavage,the keloid tissue was exfoliated and weighed,and HE staining,Masson staining,and immunohistochemical staining for TGF-β1 were conducted.Differences in keloid weight between the three groups before and after treatment were compared,as were the differences in collagen fiber,fibroblast numbers,and TGF-β1 expression between the three groups after treatment.Results The difference in keloid weight before and after treatment in the Asiaticoside tablet group was greater than that of the control group,and the weight difference before and after treatment keloid treatment was the largest in the Sanjie Quban recipe group(P＜0.01).Compared with the control group,collagen fibers in the Sanjie Quban recipe group were looser and less numerous,and fibroblasts were decreased in number.The expression of TGF-β1 in the Sanjie Quban recipe group was decreased compared with that of the control group(P＜0.01).Conclusions Sanjie Quban recipe has certain therapeutic effects on keloids.The mechanism may involve reducing the expression of TGF-βl in keloid tissue and thereby reducing the proliferation of fibroblasts and the synthesis of extracellular matrix.This study provides experimental and theoretical bases for the clinical treatment of keloids with Chinese medicine.

ObjectiveTo explore the distribution of traditional Chinese medicine （TCM） syndromes of alopecia areata （AA）， and to provide reference for TCM clinical syndrome differentiation and classification of AA. MethodsAA patients who visited the specialized hairiness clinic of Beijing China-Japan Friendship Hospital were included. A questionnaire was developed including general information of the patients， history of hair loss （onset time， triggers and exacerbating factors， disease progression）， current symptoms （symptoms and signs）， medical history， personal history， family history， and hair microscopy examination results. The factor analysis and cluster analysis were used to determine the syndrome elements and to summarize the syndrome types. ResultsA total of 600 patients with AA were included， including 218 males （36.33%） and 382 females （63.67%）. Totally， 128 patients （21.33%） had a family history of hair loss， and 326 patients （54.33%） had a previous related underlying disease. The leading triggering and exacerbating factors of AA were tension and anxiety， accounting for 335 cases （55.83%） and 285 cases （47.50%）， respectively. The top 10 symptoms involved among patients were scalp oil， anxiety， irritability， dreaminess， fatigue， itching， tension， weakness and dandruff. The factor analysis showed that the factor rotation converged after 9 iterations， and finally obtained 12 common factors and 34 variables， with a cumulative contribution rate of 58.59%. In terms of disease location of AA， the main syndrome elements were liver， spleen and kidney， and the disease nature syndrome elements were mainly dampness-heat， qi stagnation， yin deficiency， qi deficiency， and blood deficiency. The clustering analysis of the 12 common factors showed that TCM syndromes could be summarized into four categories： internal retention of damp-heat， liver-kidney deficiency， qi and blood deficiency， and liver constraint and spleen deficiency. There were significant differences in the distribution of TCM syndromes in patients of different ages and genders （P＜0.001）. ConclusionThe main disease location of AA is in the liver， spleen， and kidney， with the liver being the key. The disease mechanism of AA is a deficiency-excess complex， initially manifested as excess and later becoming deficiency. The TCM syndromes mainly include four types which are internal retention of damp-heat， liver-kidney deficiency， qi and blood deficiency， and liver constraint and spleen deficiency.

The lateral hypothalamic area (LHA) plays a pivotal role in regulating consciousness transition, in which orexinergic neurons, GABAergic neurons, and melanin-concentrating hormone neurons are involved. Glutamatergic neurons have a large population in the LHA, but their anesthesia-related effect has not been explored. Here, we found that genetic ablation of LHA glutamatergic neurons shortened the induction time and prolonged the recovery time of isoflurane anesthesia in mice. In contrast, chemogenetic activation of LHA glutamatergic neurons increased the time to anesthesia and decreased the time to recovery. Optogenetic activation of LHA glutamatergic neurons during the maintenance of anesthesia reduced the burst suppression pattern of the electroencephalogram (EEG) and shifted EEG features to an arousal pattern. Photostimulation of LHA glutamatergic projections to the lateral habenula (LHb) also facilitated the emergence from anesthesia and the transition of anesthesia depth to a lighter level. Collectively, LHA glutamatergic neurons and their projections to the LHb regulate anesthetic potency and EEG features.

Objective: To assess plantar arch index (AI) and prevalence of flat feet in school-age children (7-12 years old) in Shanghai and evaluate the relationship between flat feet with age, gender, weight status (BMI) and occurring sides, and to provide a reference for the prevention of flatfeet. Methods: Three-dimensional foot measuring instruments were used to measure bilateral foot length, medial arch height, AI and arch height ratio (AHR) in school-age children in Shanghai. Statistical analysis of these foot parameters was performed. Results: A total of 3 226 children between aged 7 and 12 in Shanghai were measured with AI of (0.27±0.05) and AHR of (3.02±1.89). Prevalence of flat feet in the group of 7 to 12 year old children was 56.1%. Prevalence of flatfeet decreased significantly with age: 72.6% at 7 years old and 37.9% at 12 years old. Boys had a significantly greater risk for flat feet than girls: the prevalence of flat feet was 62.9% for boys and 47.8% for girls (OR=1.81, 95%CI=1.57-2.10). This risk was independent of age but related to gender. The risk of flat feet in boys was always higher than that in girls at every age. For children aged 7-8, being overweight was not significantly related to the occurrence of flat feet. However, for children aged 9-12 who were overweight were more likely to have flat feet than those of normal weight. The OR increased with age: from 1.44 (95%CI=1.03-2.03) at 9 to 2.96 (95%CI=1.68-5.23) at 12. There was no difference on which side flat feet would occur (χ2=0.95，P=0.33). Conclusion This finding shows that prevalence of flat feet is influenced by age, gender and weight status. AI and prevalence of flat feet in children aged 7-12 decreases with age, and boys have significantly higher prevalence of flat feet than girls. Overweight children aged 9 or older have a higher risk of flat feet.

Objective:To investigate the effect of virtual reality (VR) attention training on cognitive function in patients with depressive episode.Methods:64 patients diagnosed as major depressive disorder and bipolar disorder depressive episodes according to the DSM-5 criteria were recruited. They were randomized into virtual reality training (VRT) group ( n=23), computerized cognitive remediation therapy (CCRT) group ( n=21) and blank control group ( n=20). Prior to the intervention, seven cognitive functions were assessed with the MATRICS Consensus Cognitive Battery (MCCB)-B version in all patients, via information processing speed (IPS), attention/alertness (ATT), working memory, word learning, visual learning (VL), reasoning and problem solving, and social cognition. VRT group and CCRT group were trained for four weeks at a frequency of five days a week, and half an hour for each day training. Blank control group did not receive any treatment related to attention training. After the training, three groups were assessed by the MCCB-A. The differences of the cognitive functions among three groups were explored by the repeated analysis of ANOVA and paired sample ttest. Results:(1) Before the intervention, there were no differences in all cognitive functions (all P>0.05) among three groups. (2) After four-week interventions, the cognition of IPS, ATT and VL in VRT group (56.74±9.68, 56.48±10.22, 57.83±4.16), CCRT group (48.90±9.77, 49.48±9.51, 55.95±5.52) and the blank control group (50.35±7.93, 47.55±7.80, 47.95±9.90) had significant groups×time interactions ( F=14.06, 12.88, 9.39, all P<0.01); simple effect analysis showed that IPS and ATT scores in VRT group were higher than both CCRT group and the blank control group (all P<0.05), while the VL scores in VRT group and CCRT group were both higher than the blank control group (all P<0.01).(3) Cognitive functions in VRT group significantly improved in IPS, ATT, VL and overall domains compared with the baseline ( t=-9.33, -6.00, -5.13, -6.26, all P<0.01). Conclusion:VR attention training may be more beneficial than CCRT attention training to improve the attention among depressive patients.

Objective:To investigate the character and prevalence of cognitive impairment of patients with bipolar Ⅱ depression (BD-Ⅱ).Methods:124 patients diagnosed as bipolar Ⅱ depression according to the DSM-5 criteria and 124 demographically matched healthy subjects were recruited. Seven cognitive functions were assessed with the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery(MCCB) in all participants, including speed of processing (SOP), attention vigilance (AV), working memory (WM), verbal learning (VER), visual learning (VIS), reasoning problem solving (RPS), and social cognition (SC), and the composite. Analysis of covariance was used to test the differences in cognitive function. The number and percentage of cognitive domains impairment which was defined as the cognitive domains scored below standard values by 1, 1.5 and 2 standard deviation (SD) were explored.Results:(1) BD-Ⅱ patients were significantly impaired on seven MCCB domains and the composite scores compared with HC (all P<0.01). Correlation analysis showed that the scores of VER, RPS negatively correlated to the number of episodes ( r=-0.212, P=0.018; r=-0.183, P=0.042); (2) Most healthy control participants were not impaired on any 2 cognitive domains at 1.5 SD (79.84%,99/124) and 2 SD (92.74%,115/124) cut-offs, with the 2.42%-6.45% cognitive impairment at the 1.5 SD cut-off, and 0-4.84% at the 2 SD cut-off accordingly. (3) At the 1.5 SD cut-off, 33.06%,41/124 of the BD-Ⅱ patients were cognitively impaired in two or more domains, while at the 2.0 SD cut-off, 14.52%,18/124 of patients were cognitively impaired. Meanwhile, the incidence of impairment in various cognitive domains was 9.68%-24.19% and 3.23%-15.32%, of which the incidence rate of visual learning impairment was 12.90%, and the incidence rate of impairment in working memory and social cognition was 24.19%. Conclusions:Participants with BD-Ⅱ depression were generally impaired on a greater number of cognitive domains with a higher percentage than the healthy controls, especially on the cognitive domains of working memory, visual learning, and social cognition. And the domains of verbal learning and reasoning problem solving were negatively correlated with the number of episodes.

Objective:To investigate the effect of virtual reality (VR) attention training on cognitive function in patients with depressive episode.Methods:64 patients diagnosed as major depressive disorder and bipolar disorder depressive episodes according to the DSM-5 criteria were recruited. They were randomized into virtual reality training (VRT) group ( n=23), computerized cognitive remediation therapy (CCRT) group ( n=21) and blank control group ( n=20). Prior to the intervention, seven cognitive functions were assessed with the MATRICS Consensus Cognitive Battery (MCCB)-B version in all patients, via information processing speed (IPS), attention/alertness (ATT), working memory, word learning, visual learning (VL), reasoning and problem solving, and social cognition. VRT group and CCRT group were trained for four weeks at a frequency of five days a week, and half an hour for each day training. Blank control group did not receive any treatment related to attention training. After the training, three groups were assessed by the MCCB-A. The differences of the cognitive functions among three groups were explored by the repeated analysis of ANOVA and paired sample ttest. Results:(1) Before the intervention, there were no differences in all cognitive functions (all P>0.05) among three groups. (2) After four-week interventions, the cognition of IPS, ATT and VL in VRT group (56.74±9.68, 56.48±10.22, 57.83±4.16), CCRT group (48.90±9.77, 49.48±9.51, 55.95±5.52) and the blank control group (50.35±7.93, 47.55±7.80, 47.95±9.90) had significant groups×time interactions ( F=14.06, 12.88, 9.39, all P<0.01); simple effect analysis showed that IPS and ATT scores in VRT group were higher than both CCRT group and the blank control group (all P<0.05), while the VL scores in VRT group and CCRT group were both higher than the blank control group (all P<0.01).(3) Cognitive functions in VRT group significantly improved in IPS, ATT, VL and overall domains compared with the baseline ( t=-9.33, -6.00, -5.13, -6.26, all P<0.01). Conclusion:VR attention training may be more beneficial than CCRT attention training to improve the attention among depressive patients.

Objective:To investigate the character and prevalence of cognitive impairment of patients with bipolar Ⅱ depression (BD-Ⅱ).Methods:124 patients diagnosed as bipolar Ⅱ depression according to the DSM-5 criteria and 124 demographically matched healthy subjects were recruited. Seven cognitive functions were assessed with the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery(MCCB) in all participants, including speed of processing (SOP), attention vigilance (AV), working memory (WM), verbal learning (VER), visual learning (VIS), reasoning problem solving (RPS), and social cognition (SC), and the composite. Analysis of covariance was used to test the differences in cognitive function. The number and percentage of cognitive domains impairment which was defined as the cognitive domains scored below standard values by 1, 1.5 and 2 standard deviation (SD) were explored.Results:(1) BD-Ⅱ patients were significantly impaired on seven MCCB domains and the composite scores compared with HC (all P<0.01). Correlation analysis showed that the scores of VER, RPS negatively correlated to the number of episodes ( r=-0.212, P=0.018; r=-0.183, P=0.042); (2) Most healthy control participants were not impaired on any 2 cognitive domains at 1.5 SD (79.84%,99/124) and 2 SD (92.74%,115/124) cut-offs, with the 2.42%-6.45% cognitive impairment at the 1.5 SD cut-off, and 0-4.84% at the 2 SD cut-off accordingly. (3) At the 1.5 SD cut-off, 33.06%,41/124 of the BD-Ⅱ patients were cognitively impaired in two or more domains, while at the 2.0 SD cut-off, 14.52%,18/124 of patients were cognitively impaired. Meanwhile, the incidence of impairment in various cognitive domains was 9.68%-24.19% and 3.23%-15.32%, of which the incidence rate of visual learning impairment was 12.90%, and the incidence rate of impairment in working memory and social cognition was 24.19%. Conclusions:Participants with BD-Ⅱ depression were generally impaired on a greater number of cognitive domains with a higher percentage than the healthy controls, especially on the cognitive domains of working memory, visual learning, and social cognition. And the domains of verbal learning and reasoning problem solving were negatively correlated with the number of episodes.