In proton therapy,prompt gamma-ray imaging is considered as one of the most promising methods for assessing proton beam range.Prompt gamma-ray imaging detector evaluates the proton beam range based on the prompt gamma-ray distribution obtained by the prompt gamma-ray imaging system,which enables high-precision measurement of the proton beam range.Herein a proton beam range verification algorithm is designed for the newly developed prototype of the range verification detector(pixelated prompt gamma-ray imaging detector),which verifies the range estimation accuracy of the prototype for different phantoms and different energies of homogeneous media through Monte Carlo simulation.The results show that the accuracy of the proton beam range verification algorithm is within 0.5 mm of the safety margin error of the Bragg peak,and the measurement accuracy is significantly improved with the increase of the number of protons,indicating that the prototype algorithm is feasible for proton beam range verification.

Objective:To investigate the relationship between nerve growth factor (NGF) concentration in follicular fluid and abnormal menstrual cycle in infertile patients with polycystic ovary syndrome (PCOS).Methods:A retrospective cohort study was conducted on 100 infertile patients with PCOS who underwent in vitro fertilization and embryo transfer (IVF-ET) at Department of Obstetrics and Gynecology, Peking University Third Hospital from March 2017 to June 2019. For comparison, the 100 patients with PCOS were divided into low NGF group ( n=50) and high NGF group ( n=50) based on the median NGF concentration (1 644.03 ng/L) in follicular fluid. Baseline characteristics, menstrual status and clinical outcomes of assisted reproductive technology were compared. We performed multiple linear regression analysis to examine the effect of NGF in follicular fluid on menstrual cycle length for multivariate analysis. Results:1) PCOS patients in the low NGF group had significantly higher body mass index [(27.24±5.17) kg/m 2] and white blood cell count [7.31(5.99, 8.43)×10 9/L ] than those in the high NGF group [(25.03±4.46) kg/m 2, P=0.024; 5.95(5.08,7.01)×10 9/L, P=0.001], while high-density lipoprotein cholesterol [1.15 (0.98, 1.36) mmol/L] and basic follicle-stimulating hormone level [6.51 (5.10,7.95) U/L] in the low NGF group were significantly lower than those in the high NGF group [1.36 (1.09,1.52) mmol/L, P=0.039;6.51 (5.10,7.95)U/L, P=0.040]. 2) PCOS patients in the low NGF group had significantly higher menstrual cycle length [60.00 (35.00, 180.00) d] than the high NGF group [32.50 (27.00,67.50) d, P=0.001]. 3) Multiple linear regression analysis revealed that after adjustment for body mass index, age, infertility duration, infertility type, and glucose and lipid metabolic parameters, the NGF concentration in the follicular fluid independently and negatively correlated with menstrual cycle length ( P<0.05). 4) The NGF concentration in follicular fluid was not correlated with assisted reproductive outcomes. Conclusion:NGF concentration in follicular fluid is closely related to the degree of menstrual cycle abnormalities in patients with PCOS.

Proprotein convertase subtilisin/kexin type 9(PCSK9)can modulate low density lipoprotein cholesterol(LDLC)levels,and its dysfunction is closely associated with the progression of atherosclerosis and cardiovascular diseases.Research has shown that PCSK9 inhibitors are highly effective in lowering lipids and have good safety and tolerability.New approaches to targeting PCSK9 inhibition are currently in different stages of clinical development.This review out-lines the primary mechanisms of PCSK9 and its impact on the cardiovascular system,emphasizing the current emerging strategies for targeting PCSK9 in lipid-lowering treatments.

Objective:To investigate the relationship between nerve growth factor (NGF) concentration in follicular fluid and abnormal menstrual cycle in infertile patients with polycystic ovary syndrome (PCOS).Methods:A retrospective cohort study was conducted on 100 infertile patients with PCOS who underwent in vitro fertilization and embryo transfer (IVF-ET) at Department of Obstetrics and Gynecology, Peking University Third Hospital from March 2017 to June 2019. For comparison, the 100 patients with PCOS were divided into low NGF group ( n=50) and high NGF group ( n=50) based on the median NGF concentration (1 644.03 ng/L) in follicular fluid. Baseline characteristics, menstrual status and clinical outcomes of assisted reproductive technology were compared. We performed multiple linear regression analysis to examine the effect of NGF in follicular fluid on menstrual cycle length for multivariate analysis. Results:1) PCOS patients in the low NGF group had significantly higher body mass index [(27.24±5.17) kg/m 2] and white blood cell count [7.31(5.99, 8.43)×10 9/L ] than those in the high NGF group [(25.03±4.46) kg/m 2, P=0.024; 5.95(5.08,7.01)×10 9/L, P=0.001], while high-density lipoprotein cholesterol [1.15 (0.98, 1.36) mmol/L] and basic follicle-stimulating hormone level [6.51 (5.10,7.95) U/L] in the low NGF group were significantly lower than those in the high NGF group [1.36 (1.09,1.52) mmol/L, P=0.039;6.51 (5.10,7.95)U/L, P=0.040]. 2) PCOS patients in the low NGF group had significantly higher menstrual cycle length [60.00 (35.00, 180.00) d] than the high NGF group [32.50 (27.00,67.50) d, P=0.001]. 3) Multiple linear regression analysis revealed that after adjustment for body mass index, age, infertility duration, infertility type, and glucose and lipid metabolic parameters, the NGF concentration in the follicular fluid independently and negatively correlated with menstrual cycle length ( P<0.05). 4) The NGF concentration in follicular fluid was not correlated with assisted reproductive outcomes. Conclusion:NGF concentration in follicular fluid is closely related to the degree of menstrual cycle abnormalities in patients with PCOS.

Proprotein convertase subtilisin/kexin type 9(PCSK9)can modulate low density lipoprotein cholesterol(LDLC)levels,and its dysfunction is closely associated with the progression of atherosclerosis and cardiovascular diseases.Research has shown that PCSK9 inhibitors are highly effective in lowering lipids and have good safety and tolerability.New approaches to targeting PCSK9 inhibition are currently in different stages of clinical development.This review out-lines the primary mechanisms of PCSK9 and its impact on the cardiovascular system,emphasizing the current emerging strategies for targeting PCSK9 in lipid-lowering treatments.

In proton therapy,prompt gamma-ray imaging is considered as one of the most promising methods for assessing proton beam range.Prompt gamma-ray imaging detector evaluates the proton beam range based on the prompt gamma-ray distribution obtained by the prompt gamma-ray imaging system,which enables high-precision measurement of the proton beam range.Herein a proton beam range verification algorithm is designed for the newly developed prototype of the range verification detector(pixelated prompt gamma-ray imaging detector),which verifies the range estimation accuracy of the prototype for different phantoms and different energies of homogeneous media through Monte Carlo simulation.The results show that the accuracy of the proton beam range verification algorithm is within 0.5 mm of the safety margin error of the Bragg peak,and the measurement accuracy is significantly improved with the increase of the number of protons,indicating that the prototype algorithm is feasible for proton beam range verification.

With the continuous development of cancer treatment technology, the cure rate for tumors in children is increasing. However, the irreversible damage to ovarian development and function by chemotherapy and radiation in surviving children often leads to iatrogenic premature ovarian failure and even infertility. Therefore, it is of great significance to develop fertility preservation techniques for children with tumors. International and domestic guidelines indicate that ovarian tissue cryopreservation and transplantation should be considered first for female children. However, the application of this technique in children is not yet mature. Current research suggests that there are significant structural and functional differences between children's ovaries and adults', and fertility preservation strategies for adults are not fully applicable to children. Therefore, this paper analyzes and reviews the structure and function of children's ovaries, the mechanism of damage to ovarian tissues by chemotherapy and radiation, and the current research and application status of fertility preservation techniques for female children. It also looks forward to the development direction of fertility preservation techniques for female children.

With the continuous development of cancer treatment technology, the cure rate for tumors in children is increasing. However, the irreversible damage to ovarian development and function by chemotherapy and radiation in surviving children often leads to iatrogenic premature ovarian failure and even infertility. Therefore, it is of great significance to develop fertility preservation techniques for children with tumors. International and domestic guidelines indicate that ovarian tissue cryopreservation and transplantation should be considered first for female children. However, the application of this technique in children is not yet mature. Current research suggests that there are significant structural and functional differences between children's ovaries and adults', and fertility preservation strategies for adults are not fully applicable to children. Therefore, this paper analyzes and reviews the structure and function of children's ovaries, the mechanism of damage to ovarian tissues by chemotherapy and radiation, and the current research and application status of fertility preservation techniques for female children. It also looks forward to the development direction of fertility preservation techniques for female children.

OBJECTIVES: Restoration of blood circulation within "time window" is the principal treating goal for treating acute ischemic stroke. Previous studies revealed that delayed recanalization might cause serious ischemia/reperfusion injury. However, plenty of evidences showed delayed recanalization improved neurological outcomes in acute ischemic stroke. This study aims to explore the role of delayed recanalization on blood-brain barrier (BBB) in the penumbra (surrounding ischemic core) and neurological outcomes after middle cerebral artery occlusion (MCAO). METHODS: Recanalization was performed on the 3rd day after MCAO. BBB disruption was tested by Western blotting, Evans blue dye, and immunofluorescence staining. Infarct volume and neurological outcomes were evaluated on the 7th day after MCAO. The expression of fibroblast growth factor 21 (FGF21), fibroblast growth factor receptor 1 (FGFR1), phosphatidylinositol-3-kinase (PI3K), and serine/threonine kinase (Akt) in the penumbra were observed by immunofluorescence staining and/or Western blotting. RESULTS: The extraversion of Evans blue, IgG, and albumin increased surrounding ischemic core after MCAO, but significantly decreased after recanalization. The expression of Claudin-5, Occludin, and zona occludens 1 (ZO-1) decreased surrounding ischemic core after MCAO, but significantly increased after recanalization. Infarct volume reduced and neurological outcomes improved following recanalization (on the 7th day after MCAO). The expressions of Claudin-5, Occludin, and ZO-1 decreased surrounding ischemic core following MCAO, which were up-regulated corresponding to the increases of FGF21, p-FGFR1, PI3K, and p-Akt after recanalization. Intra-cerebroventricular injection of FGFR1 inhibitor SU5402 down-regulated the expression of PI3K, p-Akt, Occludin, Claudin-5, and ZO-1 in the penumbra, which weakened the beneficial effects of recanalization on neurological outcomes after MCAO. CONCLUSIONS Delayed recanalization on the 3rd day after MCAO increases endogenous FGF21 in the penumbra and activates FGFR1/PI3K/Akt pathway, which attenuates BBB disruption in the penumbra and improves neurobehavior in MCAO rats.
Animals ; Rats ; Blood-Brain Barrier/metabolism* ; Brain Ischemia ; Claudin-5/metabolism* ; Infarction, Middle Cerebral Artery/metabolism* ; Ischemic Stroke/metabolism* ; Occludin/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Rats, Sprague-Dawley ; Receptor, Fibroblast Growth Factor, Type 1/metabolism* ; Reperfusion Injury/metabolism*

The number of benign prostatic obstruction (BPO) patients in China is increasing, and patients tend to be younger and younger. The former "gold standard" scheme of transurethral resection of the prostate (TURP) is more suitable for patients with prostate volume ranging from 40 mL to 80 mL, which may lead to excessive resection in patients with small prostate volume and low efficiency in patients with large prostate volume. New minimally invasive techniques have been introduced,including prostate artery embolization, laser surgery (such as holmium, green, diode, and thulium), minimally invasive simple prostatectomy, transperineal laser ablation, prostatic urethral lift,and robot-assisted water jet ablation of the prostate. These methods are alternatives to TURP and increasingly used in the treatment of BPO. This article reviewed the advances in minimally invasive treatment of BPO.