Objective To explore the expressions and distributions of glial cell line -derived neurotrophic factor (GDNF)and itstyrosine kinase receptor RET in the terminal rectums of fetal rats with congenital anorectal malfor-mations (ARM)at different gestationalage,and to explore their effects on the enteric nervous system in the terminal rectum of ARMfetal rats.Methods Thirty -five SD pregnancy rats were divided into a saline group (n =1 0)and an ethylenethiourea experiment group (n =25)by simple randomized study.The fetal rats were removed from the pregnant rats at the gestational 1 6 d,1 8 d and 20 d.The fetal rats were divided into the saline control group,the ethylenethiourea control group (fetal rats without ARM)and the ethylenethiourea malformation group (ARM fetal rats)by the naked eye and dissecting microscope.HE staining was used to observe the morphology and the intestinal ganglion cells in the terminal rectum were counted.The immunohistochemical staining and Western blot methods were used to observe the distributions of GDNF and RET in the rectum at the gestational 1 6 d,1 8 d and 20 d.The quantitative real -time poly-merase chain reaction (qRT -PCR)was used to detect the expression of GDNF mRNA in the fetal rats in the terminal rectum at the gestational 1 6 d,1 8 d and 20 d.Results HE staining:the development of anorectal terminal in 3 groups of fetal rats was unclear at the gestational 1 6 d.A small amount of scattered nerve plexuses were observed in the muscu-lar layer.The nuclei were small and sparse.The axons and cytoplasms were less.The serosal layer,muscular layer,sub-mucosa,mucosal layer and glands in the terminal rectum were gradually clear in the saline control group and the ethyle-nethiourea control group at the gestational 1 8 d and 20 d.The intermuscular submucosal nerve plexuses increased gra-dually (1 1 .400 ±3.1 34 and 1 1 .200 ±3.425 at the gestational 1 8 d;66.1 00 ±4.954 and 67.600 ±5.481 at the gesta-tional 20 d).While,the layer was unclear in the ethylenethiourea malformation group and the nerve plexus was less (7.800 ±1 .989 at the gestational 1 8 d,and 25.200 ±3.048 at the gestational 20 d),and the difference was statistical-ly significant compared with 2 control groups (F =7.591 ,271 .833,all P <0.05).Immunohistochemistry satning:the expressions of GDNF and RET in all layers of the intestinal wall in the 3 groups of fetal rats were unclear at the gesta-tional 1 6 d and only a few positive cells were observed.The GDNF and RET were expressed in the mucosal layer and submucosa of the terminal rectum as well as intermuscular nerve plexus in the saline control group and the ethylene-thioured control group at the gestational 1 8 d and 20 d.With the continuous development of the embryo,their expression intensities were gradually increased.The expressions of GDNF and RET positive cells were decreased gradually in the ethylenethiourea malformation group.The difference was significant statistically compared with 2 control groups (all P <0.05).qRT -PCR:the expressions of GDNF mRNA showed no statistical difference among 3 groups at the gestational 1 6 d (P >0.05);the expressions of GDNF and RET protein were 1 03.624 ±27.533 and 1 05.1 84 ±1 9.634 at the ges-tational 1 8 d;1 51 .496 ±33.622 and 1 50.738 ±21 .423 at the gestational 20 d in 2 control groups.Compared with the ethylenethiourea malformation group (79.1 69 ±1 1 .697 at the gestational 1 8 d;94.873 ±1 1 .309 at the gestational 20 d),and the difference were statistically significant (all P <0.05).Conclusions The expressions of GDNF and its tyrosine kinase receptor RET had a certain temporal correlation in the terminal rectum of normal fetal rats at different gestational ages and ARM.Moreover,the abnormal expressions of GDNF and its tyrosine kinase receptor RET in the dis-tal rectum of ARMfetal rats can affect the development of enteric nervous system.

Objective:To compare the clinical outcomes and correction effects of kyphosis between Zero-profile device (Zero-p) and plate/cage structures (PCC) in treating cervical spondylotic myelopathy (CSM) patients with cervical kyphosis.Methods:From August 2016 to July 2018, a total of 54 cases of cervical spondylotic myelopathy patients with cervical kyphosis were analyzed retrospectively, including 26 cases treated with Zero-p and 28 cases treated with PCC system. There was no significant difference between the two groups in gender, age, body mass index (BMI) and operative segment. The operation duration and the blood loss were recorded. The clinical outcomes of the patients were measured by visual analogue score (VAS) for neck pain and Japanese Orthopedic Association (JOA) score for neurological function. Moreover, JOA recovery rate was obtained to assess the surgical results. The cervical lordosis (C 2-C 7 Cobb angle), the Cobb angle of the operation segment, the C 2-C 7 vertical axis (C 2 SVA) and the cervical range of motion (ROM) were measured on the lateral and dynamic radiographs of the cervical spine, respectively. Results:In the Zero-p group, the operation duration was 83.0±14.9 (range 60-120) min, intraoperative blood loss was 70.5±27.3 (range 30-150) ml. In PCC group, the operation duration was 100.0±23.9 (range 65-145) min, intraoperative blood loss was 104.2±38.8 (range 30-250) ml. There were significant difference in above parameters between two groups ( t=3.40, 2.06; P=0.00, 0.04). The follow-up duration in Zero-p group was 30.4±5.8 (range 24-36) months and 31.2±4.9 (range 24-36) months in PCC group without significant difference ( t=1.061, P=0.291). The VAS/JOA score of the Zero-p group was improved from (5.9±1.0)/(9.2±1.7) preoperatively to (2.1±0.8)/(14.9±1.0) at 1 month postoperatively, and to (3.4±1.0)/(15.1±0.9) at the last follow-up. The difference between them was statistically significant ( F=130.96, 221.40, P=0.00). The VAS/JOA score of the PCC group was improved from (5.9±1.1)/(8.7±1.6) preoperatively to (2.3±0.9)/(14.9±1.0) at 1 month after surgery, and to (2.6±0.9)/(15.6±1.1) at the last follow-up. The difference between them was statistically significant ( F=303.35, 126.64, P=0.00). However, the VAS score of neck pain in the Zero-p group at the last follow-up was significantly deteriorated, which was significantly higher than that in PCC group ( P<0.05). The cervical lordosis/operative segment Cobb angle in the Zero-p group was improved from preoperative (-6.7°±2.7°)/(-6.5°±3.2°) preoperatively to (14.2°±4.9°)/(12.9°±4.9°) at 1 month postoperatively, and to (5.9°±4.7°)/(5.0°±4.0°) at the last follow-up with statistical significance ( F=196.98, 179.97, P=0.00). The cervical lordosis/operative segment Cobb angle in the PCC group was improved from (-5.7°±3.5°)/(-6.1°±4.0°) preoperatively to (13.9°±6.9°)/(13.0°±6.4°) 1 month after surgery, and to (11.0°±5.5°)/(10.4°±5.6°) at the last follow-up with statistical significance ( F=127.27, 119.98, P=0.00). However, the cervical lordosis and operative segment Cobb angle at the last follow-up in the Zero-p group were significantly lost compared with those at 1 month after surgery, which were significantly smaller than those in the PCC group ( P<0.05). The incidence of dysphagia after operation was 7.7% (2/26) in the Zero-p group and 28.6% (8/28) in the PCC group (χ 2=5.11, P=0.02). Conclusion:For CSM patients with cervical kyphosis, PCC could achieve much better mid-term kyphotic correction and clinical outcomes. However, Zero-p should be avoided as much as possible.

BACKGROUND: Cell competition is an important feature in pancreatic cancer (PC) progression, but the underlying mechanism remains elusive. This study aims to explore the role of exosomes derived from normal pancreatic ductal epithelial cells involved in PC progression. METHODS: PC cells and pancreatic stellate cells (PSCs) were treated with exosomes isolated from pancreatic ductal epithelial cells. Cell proliferation was assessed by CCK8 assays. Cell migration and invasion were assessed by Transwell assays. PC and matched adjacent non-tumor tissue specimens were obtained from 46 patients pathologically diagnosed with PC at Peking University First Hospital from 2013 to 2017. Tissue miR-485-3p and p21-activated kinase-1 (PAK1) expression was examined by real-time polymerase chain reaction (RT-PCR), and the relationship of the two was analyzed using Pearman's product-moment correlation. The clinical significance of miR-485-3p was analyzed using the Chi-square test, Wilcoxon rank-sum test, and Fisher exact probability, respectively. The binding of miR-485-3p to PAK1 5'-untranslated region (5'-UTR) was examined by luciferase assay. PC cells were xenografted into nude mice as a PC metastasis model. RESULTS: Exosomes from pancreatic ductal epithelial cells suppressed PC cell migration and invasion as well as the secretion and migration of PSCs. MiR-485-3p was enriched in the exosomes of pancreatic ductal epithelial cells but deficient in those of PC cells and PSCs, in accordance with the lower level in PSCs and PC cells than that in pancreatic ductal cells. And the mature miR-485-3p could be delivered into these cells by the exosomes secreted by normal pancreatic duct cells, to inhibit PC cell migration and invasion. Clinical data analysis showed that miR-485-3p was significantly decreased in PC tissues (P < 0.05) and was negatively associated with lymphovascular invasion (P = 0.044). As a direct target of miR-485-3p, PAK1 was found to exert an inhibitory effect on PC cells, and there was a significantly negative correlation between the expression levels of miR-485-3p and PAK1 (r = -0.6525, P < 0.0001) in PC tissues. Moreover, miR-485-3p could suppress PC metastasis in vivo by targeting p21-activated kinase-1. CONCLUSIONS Exosomal miR-485-3p delivered by normal pancreatic ductal epithelial cells into PC cells inhibits PC metastasis by directly targeting PAK1. The restoration of miR-485-3p by exosomes or some other vehicle might be a novel approach for PC treatment.
Animals ; Mice ; MicroRNAs/metabolism* ; Mice, Nude ; p21-Activated Kinases/metabolism* ; Cell Line, Tumor ; Pancreatic Neoplasms/genetics* ; Epithelial Cells/metabolism* ; Pancreatic Ducts/pathology* ; Cell Proliferation ; Cell Movement ; Gene Expression Regulation, Neoplastic