Objective To study the role of cutaneous nerve and protease activated receptor 2 (PAR2)in the development of pruritus in atopic dermatitis(AD).Methods Dermal sheets were prepared from chronically pruritic skin lesions of 7 patients with AD,as well as from the normal skin of 7 healthy human controls.Double labeled immunofluorescence was performed using mouse anti-protein gene product 9.5(PGP9.5)monoclonal antibody and rabbit anti-substance P(SP)polyclonal antibody to observe the morphological changes in cutaneous nerve fibers,and Image-Pro Plus 6 software was used to semiquantitively assess the length,diameter of nerve fibers,integral optimal density of PAR2 and SP in dermal sheets.Results Immunofluoresence double staining showed that PAR2 co-expressed with PGP9.5 or SP in cutaneous nerve fibers.Compared with the normal control skin,both the total length and average diameter of PGP 9.5-expressing nerve fibers were increased(11051.8±1900.9 μm vs 7264.0±2659.9 μm,4.23±0.15 μm vs 3.95±0.15 μm,both P＜0.01)in pruritic lesions,while only the average diameter of SP-expressing nerve fibers was up-regulated(3.99±0.20 μm vs 3.80±0.07 μm,P＜0.05),and the total length of them remained unchanged(4304.7±1455.0 μm vs 3380.0±1735.4 μm,P＞0.05).Also,increased integral optimal density was observed for SP and PAR in pruritic lesions in comparison with the normal control skin (27.71±16.52 vs 12.63±4.31.35.99±8.63 vs 22.69±9.56.both P＜0.05).Conclusion Our results indicate a hyper-plasia of cutaneous nerve fibers in chronic itchv skin lesions of AD and an increase in the expression of PAR2 and SP in the cutaneous nerve fibers,suggesting that the signal enhancement in PAR2 pathway may be related to the mechanism of pruritus in patients with AD.

Objective To explore the effect of transcranial direct current stimulation(tDCS)based on music therapy on insomnia. Methods From July,2023 to April,2024,70 patients with insomnia in the Fourth Affiliated Hospital of Soochow Univer-sity were randomly divided into control group(n=35)and observation group(n=35).Both groups accepted mu-sic therapy;moreover,the observation group accepted tDCS,and the control group accepted sham tDCS,for four weeks.They were assessed with Pittsburgh Sleep Quality Index(PSQI)total score and sub-score,Hamilton De-pression Scale 17-item(HAMD-17),Hamilton Anxiety Scale(HAMA),Chinese version of Stress Perception Scale(CPSS);and the relative power of resting-state electroencephalography(EEG)and mean blood flow veloci-ty(Vm)of each cerebral artery with transcranial Doppler were measured before and after treatment. Results Five cases dropped down in the control group,and four in the observation group.PSQI total score and sub-score,HAMD-17 score,HAMA score and CPSS score(|t|>3.503,P<0.01)in the observation group decreased after treatment,and were less in the observation group than in the control group(|t|>2.304,P<0.05),except sleep duration,sleep efficiency and CPSS scores.The relative power of δ and θ increased in the observation group,and decreased in α,β and γ(|t|>6.468,P<0.001),and were better in the observation group than in the control group(|t|>2.395,P<0.05).The Vm of each artery increased in the observation group(|t|>4.624,P<0.001),and were more in the observation group than in the control group(|t|>2.147,P<0.05). Conclusion tDCS based on music therapy may further improve sleep quality and EEG activity,increase cerebral blood flow velocity,and reduce adverse emotions in insomnia patients.