Objective:To construct adjustable stiffness hydrogels based on gelatin methacryloyl (GelMA), in order to better simulate the growth environment under physiological conditions.Methods:SYLGARD 184 silicone rubber was used to prepare adjustable stiffness hydrogels. The stiffness values of the adjustable stiffness hydrogels prepared with GelMA of different grafting rates (30%, 60%, 90%) at various concentrations (5%, 10%, 15%) were quantified using Young’s modulus. Based on the result, the optimal grafting rate GelMA was selected as the material for constructing the adjustable stiffness hydrogels. The relationship between the concentration (2%, 3%, 5%, 6%, 8%, 10%, 15%) of 90% grafting rate (GM90) and the stiffness after photopolymerization was determined by measuring the Young’s modulus of GelMA at different concentrations and fitting the data. Three groups of suitable concentrations were chosen to construct three different stiffness hydrogels. After soaking in phosphate-buffered saline for 48 hours, various samples underwent biomechanical measurements, internal pore structure observation, atomic force microscopy to measure parameters such as Young’s modulus, pore size and surface roughness. Rheological tests were carried out, curves were drawn according to the energy storage modulus and loss modulus, and shear frequencies of the intersection points of the two curves were observed at each concentration to evaluate the ability of hydrogel to maintain its morphology. Data analysis was performed using GraphPad Prism 8.0.2 software. Quantitative data were expressed as Mean±SD, and one-way ANOVA was used for comparison among multiple groups, and LSD method was used for pairwise comparison. Statistical significance was set at P<0.05. Results:Increasing the grafting rate and concentration of GelMA hydrogels effectively enhanced their stiffness. GelMA with a GM90 provided a broader range of stiffness, making it suitable for constructing the adjustable stiffness hydrogels. Fitting curves of GM90 concentrations and stiffness after photopolymerization showed that at concentrations of 2%, 6%, and 15%, GelMA could mimic the stiffness of various tissues of human. Therefore, these three concentrations were selected for subsequent experiments. The Young’s modulus of GM90 at concentrations of 15%, 6% and 2% were (98.43±7.71), (14.57±1.62), and (2.11±0.32) kPa, respectively, with statistically significant differences between each pair of groups ( P<0.01). The pore sizes were (41.32±3.51), (3.26±0.33), and (1.21±0.11) μm, respectively, showing significant differences between each pair of groups ( P<0.01). Surface roughness values were (48.15±2.65), (22.65±1.78), and (24.12±1.43) nm, respectively, with 15% concentration showing significantly higher roughness than the 2% and 6% concentrations ( P<0.01), while there was no significant difference between the 2% and 6% concentrations ( P>0.05). Rheological testing indicated that as the concentration decreased, the shear frequency at the crossover point of the storage modulus and loss modulus of GM90 hydrogels decreased, >100, 30 and 18 Hz, respectively. The result showed that the solid form of GM90 hydrogel with 15% concentration was more stable, while the hydrogel with 2% concentration had better fluidity. Conclusion:Adjusting the grafting rate and concentration can regulate the stiffness of GelMA hydrogels. GelMA hydrogels with a 90% grafting rate provide a wide range of stiffness, making them ideal materials for constructing hydrogels with adjustable stiffness. At concentrations of 2%, 6%, and 15%, GM90 exhibited different mechanical properties and internal structures.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the clinical application value of transrectal real-time tissue elastography(TRTE)guided targeted puncture in the diagnosis of prostate cancer.Methods A total of 52 patients with suspected prostate cancer who were treated in the First People's Hospital of Zhengzhou from January 2020 to December 2022 were selected as the study objects.Preoperative routine transrectal ultrasound and TRTE examination were performed to evaluate the benign and malignant prostates.For the 28 patients with suspected lesions found in TRTE,TRTE-guided targeted puncture(2 needles)+ systematic puncture(8 needles)were performed,for the 24 patients with no suspicious lesions found in TRTE,routine ultrasound-guided systematic puncture(12 needles)was performed.The efficacy of TRTE in the diagnosis of prostate cancer was analyzed and the positive rate of targeted puncture and systematic puncture was compared.Results In this study,25 cases of prostate cancer and 27 cases of benign lesions were ultimately pathologically diagnosed,while a total of 28 cases of prostate cancer and 24 cases of benign lesions were diagnosed with TRTE.The positive predictive value and negative predictive value of the diagnosis were 75.0%(21/28)and 83.3%(20/24),respectively.In 28 patients with suspected lesions found by TRTE,a total of 56 needles were targeted puncture,36 needles were diagnosed with prostate cancer,positive rate was 64.29%(36/56),and a total of 224 needles were systematic puncture,89 needles were diagnosed with prostate cancer,with a positive rate of 39.73%(89/224).The positive rate of prostate cancer by targeted puncture was significantly higher than that by systematic puncture(P<0.05).Conclusion TRTE can better diagnose prostate cancer,and its guided targeted puncture has a higher positive rate in the diagnosis of prostate cancer,which can maximize the positive rate of puncture while reducing the number of puncture needles.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective To investigate the effects of pre-electroacupuncture(EA)on spatial learning and memory,the locus coeruleus-hippocampal neural circuit,and neuroinflammation in Alzheimer's disease(AD)-like rats,and to explore the possible mechanism of pre-EA in preventing and treating AD.Methods Thirty-six male SD rats were divided into the normal,model,EA,and sham EA groups using the random number table method,with nine rats per group.An AD-like rat model was prepared through intraperitoneal injection of 120 mg/(kg·d)D-galactose for eight consecutive weeks.After daily intraperitoneal injection,the rats in the EA group underwent EA stimulation at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints with a continuous wave,frequency of 50 Hz,and a current of 1 mA for 20 min once a day for 8 weeks.The sham EA group was only superficially punctured to the subcutaneous tissue at the"Neiguan"(PC6)and"Jianshi"(PC5)acupoints without electricity,and the rest of the operations were the same as those in the EA group.The Morris water maze experiment was then used to evaluate the spatial learning and memory of the rats.Immunofluorescence labeling was used to detect dopamine β hydroxylase and c-Fos co-localization in the locus coeruleus of noradrenergic neurons,as well as glial fibrillary acidic protein and tumor necrosis factor-α(TNF-α)co-localization in the CA1 area of the hippocampus of astrocytes.Western blotting was used to measure the protein expressions of norepinephrine(NE),β2-adrenergic receptor(β2AR),β-inhibitory protein 2(β-arrestin2),nuclear transcription factor-κB(NF-κB)inhibitory factor protein α(IκBα),and NF-κB in the hippocampus of rats.An enzyme-linked immunosorbent assay was used to detect the TNF-α,interleukin-1β(IL-1β),and interleukin-6(IL-6)contents in hippocampal tissue.Results Compared with the normal group,the average escape latency of the model group rats was prolonged,and the times of crossing platform and exploration time in the target quadrant were reduced(P<0.01),while the EA intervention can shorten the average escape latency and increase the times of crossing platform and exploration time in the target quadrant(P<0.01).Compared with the normal group,the expression of co-located noradrenergic neurons in the model group decreased,co-located astrocytes increased(P<0.01);NE,β2AR,β-arrestin2,and IκBα protein expression decreased(P<0.01),NF-κB protein expression increased(P<0.01);the contents of TNF-α,IL-1β,and IL-6 increased(P<0.01).Compared with the model group,the EA group showed an increase in the expression of co-located noradrenergic neurons,a decrease in co-located astrocytes(P<0.01),an increase in NE,β2AR,β-arrestin2,and IκBα protein expressions(P<0.01),a decrease in NF-κB protein expression(P<0.01),and a decrease in TNF-α,IL-1β,and IL-6 levels(P<0.01).No significant difference was observed in the above indicators between the model and sham EA groups.Conclusion Pre-EA at"Neiguan"(PC6)and"Jianshi"(PC5)can alleviate learning and memory dysfunction,alleviate noradrenergic neuronal loss in the locus coeruleus,inhibit astrocyte activation,protect the locus coeruleus-hippocampal neural circuit,and may be associated with inhibiting β2AR/β-arrestin2/NF-κB inflammatory pathway activation.

Objective:To construct adjustable stiffness hydrogels based on gelatin methacryloyl (GelMA), in order to better simulate the growth environment under physiological conditions.Methods:SYLGARD 184 silicone rubber was used to prepare adjustable stiffness hydrogels. The stiffness values of the adjustable stiffness hydrogels prepared with GelMA of different grafting rates (30%, 60%, 90%) at various concentrations (5%, 10%, 15%) were quantified using Young’s modulus. Based on the result, the optimal grafting rate GelMA was selected as the material for constructing the adjustable stiffness hydrogels. The relationship between the concentration (2%, 3%, 5%, 6%, 8%, 10%, 15%) of 90% grafting rate (GM90) and the stiffness after photopolymerization was determined by measuring the Young’s modulus of GelMA at different concentrations and fitting the data. Three groups of suitable concentrations were chosen to construct three different stiffness hydrogels. After soaking in phosphate-buffered saline for 48 hours, various samples underwent biomechanical measurements, internal pore structure observation, atomic force microscopy to measure parameters such as Young’s modulus, pore size and surface roughness. Rheological tests were carried out, curves were drawn according to the energy storage modulus and loss modulus, and shear frequencies of the intersection points of the two curves were observed at each concentration to evaluate the ability of hydrogel to maintain its morphology. Data analysis was performed using GraphPad Prism 8.0.2 software. Quantitative data were expressed as Mean±SD, and one-way ANOVA was used for comparison among multiple groups, and LSD method was used for pairwise comparison. Statistical significance was set at P<0.05. Results:Increasing the grafting rate and concentration of GelMA hydrogels effectively enhanced their stiffness. GelMA with a GM90 provided a broader range of stiffness, making it suitable for constructing the adjustable stiffness hydrogels. Fitting curves of GM90 concentrations and stiffness after photopolymerization showed that at concentrations of 2%, 6%, and 15%, GelMA could mimic the stiffness of various tissues of human. Therefore, these three concentrations were selected for subsequent experiments. The Young’s modulus of GM90 at concentrations of 15%, 6% and 2% were (98.43±7.71), (14.57±1.62), and (2.11±0.32) kPa, respectively, with statistically significant differences between each pair of groups ( P<0.01). The pore sizes were (41.32±3.51), (3.26±0.33), and (1.21±0.11) μm, respectively, showing significant differences between each pair of groups ( P<0.01). Surface roughness values were (48.15±2.65), (22.65±1.78), and (24.12±1.43) nm, respectively, with 15% concentration showing significantly higher roughness than the 2% and 6% concentrations ( P<0.01), while there was no significant difference between the 2% and 6% concentrations ( P>0.05). Rheological testing indicated that as the concentration decreased, the shear frequency at the crossover point of the storage modulus and loss modulus of GM90 hydrogels decreased, >100, 30 and 18 Hz, respectively. The result showed that the solid form of GM90 hydrogel with 15% concentration was more stable, while the hydrogel with 2% concentration had better fluidity. Conclusion:Adjusting the grafting rate and concentration can regulate the stiffness of GelMA hydrogels. GelMA hydrogels with a 90% grafting rate provide a wide range of stiffness, making them ideal materials for constructing hydrogels with adjustable stiffness. At concentrations of 2%, 6%, and 15%, GM90 exhibited different mechanical properties and internal structures.