Objective To observe the value of T2 mapping for quantitatively evaluating the changes of junctional zone and outer myometrium caused by endometrial fibrosis.Methods A total of 73 infertility patients with endometrial fibrosis confirmed by hysteroscopy(disease group)and 33 healthy women of childbearing age(control group)were prospectively enrolled,and MR examinations were performed at the late proliferative phase of endometrium.The thickness and T2 value of junctional zone,T2 value of outer myometrium on anterior,posterior and fundus wall of midsagittal corpus uteri were measured,and the mean value of the above measurements on the three walls were calculated.Receiver operating characteristic curves were constructed,the areas under the curves(AUC)were calculated to explore the efficacy of those with significant difference among the mean thickness and the mean T2 value of junctional zone,the mean T2 value of outer myometrium and their combination for evaluating endometrial fibrosis.Results The thickness and T2 value of anterior wall,posterior wall,fundus wall and the mean junctional zone in disease group were all significantly higher than those in control group(all P＜0.001).No significant difference of T2 value of anterior wall,posterior wall,fundus wall nor the mean outer myometrium was found between groups(all P＞0.05).The mean thickness and the mean T2 value of junctional zone and their combination could be used to effectively evaluate endometrial fibrosis,with AUC of 0.839,0.822 and 0.922,respectively,and their combination had the best performance(both P＜0.01).Conclusion T2 mapping could be used to quantitatively evaluate the injury of junctional zone caused by endometrial fibrosis.

BACKGROUND:Transcranial magnetic stimulation has been used in the treatment of Alzheimer's disease,but its mechanism has not been fully clarified. OBJECTIVE:To explore the mechanism of repetitive transcranial magnetic stimulation to increase neural excitability in mice with Alzheimer's disease. METHODS:Sixteen C57BL/6 mice were randomized into control group (n=8) and control+magnetic stimulation group (n=8). Another 16 APP/PS1 mice were randomized into dementia group (n=8) and dementia+magnetic stimulation group (n=8). Mice in the two magnetic stimulation groups were given repetitive transcranial magnetic stimulation,2 hours daily,for 14 continuous days. The water maze was then used to detect the cognitive function of mice. Whole-cell membrane-clamp technique was used to collect action potentials and analyze the effect of Alzheimer's disease on action potentials;and the potassium channe currents were collected and analyzed for the role of their kinetic properties on neural excitability. RESULTS AND CONCLUSION:The results of Morris water maze showed that normal mice could find and determine the original platform more accurately after receiving repetitive transcranial magnetic stimulation,while Alzheimer's disease led to a decrease in the learning and memory ability of mice,a decrease in the number of times they found the platform,and a degeneration of neurons in the hippocampal dentate gyrus. Repetitive transcranial magnetic stimulation could improve the learning and memory ability of mice with Alzheimer's disease. Whole-cell membrane clamp technique assay showed that repetitive transcranial magnetic stimulation could trigger neuronal depolarization and enhance neuronal excitability in Alzheimer's disease mice. Analysis of potassium channel currents showed that Alzheimer's disease caused an increase in the transient outward potassium channel half-activation voltage. The inactivation curve was shifted in the direction of depolarization and the resuscitation time constant was prolonged,causing the delayed rectifier potassium channel activation curve to be shifted in the direction of depolarization. Whereas repetitive transcranial magnetic stimulation delayed the opening and closing of the potassium channel and inhibit the efflux of intracellular potassium ions,which resulted in the retention of a higher intracellular potassium concentration and increased neuronal excitability. To conclude,repetitive transcranial magnetic stimulation may alleviate cognitive decline by increasing neuronal excitability in the hippocampal dentate gyrus.

BACKGROUND:Transcranial magnetic stimulation has been used in the treatment of Alzheimer's disease,but its mechanism has not been fully clarified. OBJECTIVE:To explore the mechanism of repetitive transcranial magnetic stimulation to increase neural excitability in mice with Alzheimer's disease. METHODS:Sixteen C57BL/6 mice were randomized into control group (n=8) and control+magnetic stimulation group (n=8). Another 16 APP/PS1 mice were randomized into dementia group (n=8) and dementia+magnetic stimulation group (n=8). Mice in the two magnetic stimulation groups were given repetitive transcranial magnetic stimulation,2 hours daily,for 14 continuous days. The water maze was then used to detect the cognitive function of mice. Whole-cell membrane-clamp technique was used to collect action potentials and analyze the effect of Alzheimer's disease on action potentials;and the potassium channe currents were collected and analyzed for the role of their kinetic properties on neural excitability. RESULTS AND CONCLUSION:The results of Morris water maze showed that normal mice could find and determine the original platform more accurately after receiving repetitive transcranial magnetic stimulation,while Alzheimer's disease led to a decrease in the learning and memory ability of mice,a decrease in the number of times they found the platform,and a degeneration of neurons in the hippocampal dentate gyrus. Repetitive transcranial magnetic stimulation could improve the learning and memory ability of mice with Alzheimer's disease. Whole-cell membrane clamp technique assay showed that repetitive transcranial magnetic stimulation could trigger neuronal depolarization and enhance neuronal excitability in Alzheimer's disease mice. Analysis of potassium channel currents showed that Alzheimer's disease caused an increase in the transient outward potassium channel half-activation voltage. The inactivation curve was shifted in the direction of depolarization and the resuscitation time constant was prolonged,causing the delayed rectifier potassium channel activation curve to be shifted in the direction of depolarization. Whereas repetitive transcranial magnetic stimulation delayed the opening and closing of the potassium channel and inhibit the efflux of intracellular potassium ions,which resulted in the retention of a higher intracellular potassium concentration and increased neuronal excitability. To conclude,repetitive transcranial magnetic stimulation may alleviate cognitive decline by increasing neuronal excitability in the hippocampal dentate gyrus.

Objective To observe the value of T2 mapping for quantitatively evaluating the changes of junctional zone and outer myometrium caused by endometrial fibrosis.Methods A total of 73 infertility patients with endometrial fibrosis confirmed by hysteroscopy(disease group)and 33 healthy women of childbearing age(control group)were prospectively enrolled,and MR examinations were performed at the late proliferative phase of endometrium.The thickness and T2 value of junctional zone,T2 value of outer myometrium on anterior,posterior and fundus wall of midsagittal corpus uteri were measured,and the mean value of the above measurements on the three walls were calculated.Receiver operating characteristic curves were constructed,the areas under the curves(AUC)were calculated to explore the efficacy of those with significant difference among the mean thickness and the mean T2 value of junctional zone,the mean T2 value of outer myometrium and their combination for evaluating endometrial fibrosis.Results The thickness and T2 value of anterior wall,posterior wall,fundus wall and the mean junctional zone in disease group were all significantly higher than those in control group(all P＜0.001).No significant difference of T2 value of anterior wall,posterior wall,fundus wall nor the mean outer myometrium was found between groups(all P＞0.05).The mean thickness and the mean T2 value of junctional zone and their combination could be used to effectively evaluate endometrial fibrosis,with AUC of 0.839,0.822 and 0.922,respectively,and their combination had the best performance(both P＜0.01).Conclusion T2 mapping could be used to quantitatively evaluate the injury of junctional zone caused by endometrial fibrosis.