ObjectiveTo investigate the effect of curcumin on the cycle arrest of human colon cancer HCT116 cells and decipher the possible molecular mechanism. MethodThe methyl thiazolyl tetrazolium （MTT） method was employed to examine the effects of curcumin （0， 12.5， 25， 50， 75， 100 μmol·L^-1） and 5-fluorouracil （5-FU， 600 μmol·L^-1） on the proliferation of HCT116 cells at different time points （24， 48， 72 h）. Flow cytometry was employed to examine the cycle of HCT116 cells treated with curcumin （0， 25， 50， 75 μmol·L^-1） and 5-FU. Western blot was employed to determine the expression of proteins in the Janus kinase 1 （JAK1）/signal transducer and activator of transcription 1 （STAT1） /cyclin-dependent kinase inhibitor 1A （p21） pathway in HCT116 cells. The binding of STAT1 to p21 promoter region was detected by chromatin immunoprecipitation （ChIP）. Small interfering RNA （siRNA） was employed to measure the role of STAT1 in regulating the expression of p21 and that of JAK1 in regulating the activation of STAT1 by Western blot and cellular immunofluorescence， respectively. ResultCompared with the blank group， the HCT-116 cells treated with curcumin and 5-FU showed decreased viability （P<0.05）， increased proportions of cells in the G₀/G₁ phase （P<0.05）， decreased proportions of cells in the S phase and G₂/M phase （P<0.05）， down-regulated protein level of phosphorylated p21 （P<0.05）， and up-regulated protein level of p21 （P<0.05）. Compared with the curcumin group， the p21 siRNA+ curcumin group presented decreased proportion of cells in G₀/G₁ phase （P<0.05）. Compared with the blank group， curcumin elevated the level of phosphorylated STAT1 （p-STAT1） （P<0.05）. Compared with the curcumin group， the curcumin + STAT1 siRNA group showcased up-regulated protein level of p21 in HCT116 cells （P<0.05）. The mechanism study showed that curcumin treatment enhanced the enrichment of STAT1 in the p21 promoter region （P<0.05） compared with the blank group. Compared with the blank group， curcumin up-regulated the level of phosphorylated JAK1 （p-JAK1） （P <0.05）. Compared with the curcumin group， the curcumin + STAT1 siRNA group demonstrated up-regulated protein levels of p-STAT1 and p21 in HCT116 cells （P<0.05）. ConclusionCurcumin may induce the cycle arrest of human colon cancer HCT116 cells by activating the JAK1/STAT1/p21 signaling pathway.

The Clinical Medicine Proficiency Test developed by the National Medical Examination Center of China in 2020 aims to assess whether clinical medical students possess the necessary medical humanities and basic medical theoretical knowledge and skills required for clinical internships. Since 2002, Japan has implemented the pre-clinical clerkship objective structured clinical examination and computer-based testing, which share similarities with China's proficiency test in terms of examination objectives, content, format, and score evaluation. Through comparing the examinations of China and Japan, this article concludes that it is necessary to learn from Japan's experience to expedite the process of promoting the Clinical Medicine Proficiency Test as an industry admission examination in China. We suggest that medical schools should keep tracking the development of the proficiency test and fully leverage its role in urging students to pay more attention to clinical internships. We also urge medical schools to establish a three-level examination system based on post competency criteria in line with the standards of the National Medical Licensing Examination to improve the quality of medical education.

Objective: To elucidate the differences in manual acupuncture effectiveness at sensitized points by investigating the mechanisms of local skin action at different sensitization points in rats with knee osteoarthritis (KOA). Methods: Forty Sprague–Dawley rats were equally divided into control, model (1 mg of monoiodoacetate into the right knee joint cavity), sham operation, manual acupuncture at right Tianjing acupoint (MAR-SJ 10), and left SJ 10 groups. Safranine-O and fast green staining were used to assess the modeling. The morphological and functional changes in mast cells (MCs) were assessed during acupoint sensitization using toluidine blue and immunofluorescence staining. The levels of serotonin, histamine, substance P (SP), and tryptase at skin acupoints and serum levels of IL-β, IL-6, and TNF-α were detected using ELISA. Results: After 14 days of treatment, the number of MCs and their degranulation rates were statistically higher in the model group than in the control group (both P < .001). After applying acupuncture, the levels of 5-HT, HA, and SP at skin acupoints were lower than those in the model group (all P < .05), and tryptase level was higher (both P < .05). Tryptase level was higher on the skin at the MAL-SJ 10 acupoint than that on the MAR-SJ 10 acupoint (P = .004). Compared with the model group, the serum levels of IL-1β, IL-6, and TNF-α in the MAR-SJ 10 and MAL-SJ 10 groups were lower (all P < .05). Conclusion Acupuncture at KOA-sensitized acupoints mitigates joint injury in KOA rats and may bidirectionally regulate local MCs of these acupoints. This finding not only enhances the reference value of sensitizing points in clinical diagnosis and treatment, but also contributes to the understanding of the biological mechanisms underlying acupuncture intervention at sensitizing points.

This study explored the variation of bursting force of multi-chamber infusion bag with different geometry size, providing guidance for its optimal design. Models of single-chamber infusion bag with different size were established. The finite element based on fluid cavity method was adopted to calculate the fluid-solid coupling deformation process of infusion bag to obtain corresponding critical bursting force. As a result, we proposed an empirical formula predicting the critical bursting force of one chamber infusion bag with specified geometry size. Besides, a theoretical analysis, which determines the force condition of three chamber infusion bag when falling from high altitude, was conducted. The proportion of force loaded on different chamber was gained. The results indicated that critical bursting force is positively related to the length and width of the chamber, and negatively related to the height of the chamber. While the infusion bag falling, the impact force loaded on each chamber is proportional to the total liquid within it. To raise the critical bursting force of in fusion bag, a greater length and width corresponding to reduced height are recommended considering the volume of liquid needed to be filled in.

On March 24, 2017, a patient with Von Hippel-Lindau syndrome (VHL) characterized by bilateral adrenal pheochromocytoma and pancreatic tumors was admitted to our hospital, who underwent simultaneous pancreatic body and tail tumor resection, bilateral adrenal tumor resection and Omentum transplantation of the right adrenal gland.Intraoperative hormone therapy was used. Part of the normal adrenal tissue was preserved and embedded in the omentum, but an adrenal crisis occurred on the first day after the operation.The hormone replacement was used. Postoperative hormone replacement therapy was performed for 6 months. After 4 years of follow-up, blood pressure was normal, no cortical dysfunction, no tumor recurrence or other related lesions appeared. The preserved part of adrenal tissue during simultaneous multi-organ tumor resection for such patients can reduce long-term hormone replacement after surgery and prevent late adrenal cortex dysfunction.

Objective To investigate the feasibility and safety of hybrid surgery in treatment of chronic symptomatic internal carotid artery occlusion.MethodsFrom April 2016 to December 2018, 9 patients with chronic symptomatic internal carotid artery occlusion confirmed by digital subtraction angiography were treated with carotid endarterectomy (CEA)+double chamber Fogarty balloon (3F) embolectomy or stent implantation when necessary. The clinical data of these patients were retrospectively analyzed. Vascular recanalization and complications during perioperative period and follow-up of the patients were analyzed.ResultsCEA+double chamber Fogarty balloon (3F) thrombectomy was performed in 5 patients; and stent placement was performed in 4 patients after Fogarty balloon thrombectomy. The internal carotid arteries of all 9 patients were unobstructed immediately during the operation. Postoperative hyperperfusion syndrome occurred in 3 patients; blood pressure was strictly controlled and the symptoms gradually relieved after proper dehydration. No serious complications such as cerebral hemorrhage, cerebral infarction, or nerve injury occurred. The duration of follow-up was 4-36 months; no patient developed a new stroke or death; no re-occlusion appeared; but one mild restenosis (50％) was detected. one patient suffered from a TIA attack 6 months after operation. ConclusionHybrid surgery is an effective method for treatment of chronic symptomatic internal carotid artery occlusion; however, preoperative evaluation and selection of patients should be carefully; individualized treatment plans should be developed.

Objective:To establish the methods for the determination of Mg,Al,K,Ca,Cr,Cu,Zn,As,Se,Ag,Cd,Sn,Ba,Pb,Na and Hg in water for injection. Methods:The sixteen metallic elements in water for injection were determined by ICP-MS. The collision cell technology ( CCT) was used to minimize the multiple atomic interference, and the matrix effect and signal drift were compensated by using Li, Sc, Ge, In, Ir and Bi as the internal standards and the samples were directly acidified to detect the metallic elements. Results:The detection limit range of the 16 metallic elements were from 0. 009 to 0. 165 ng·ml-1. The calibration curves showed good linearity (r≥0. 999 0). The recoveries were within the range of 80%-120%(n=6). Conclusion:The method is simple, rapid and accurate. It can be used to determine the contents of metallic elements to reduce the potential exceeding limit risk of toxic metal el-ements in water for injection. The methods also can provide reference for the more strict quality evaluation of water for injection.

Objective To identify the miR-122 which regulateing GATA4 expression during the induction of rat bone marrow mesenchymal stem cells (bMSCs) differentiating into cardiomyocyte-like cells. Methods BMSCs were isolat-ed from bone marrow and induced to differentiate into cardiomyocyte-like cells using 5-azacytidine. The miR-122 which may regulate expression of GATA4 were predicted using miRanda and TargetScan softwares and identified by dual luciferase report system. The expressions of miR-122 and GATA4 were determined using q-PCR during the differentiation of bMSCs into cardiomyocyte-like cells. Results The induced cells were completely in contacted with adjoining cells and uniform in shape and aligned parallelly. Cardiac troponin I (cTnI) expression was detected by immunofluorescence cytochemistry. Using dual luciferase reporter system in vitro, miR-122 were proved to be able to effectively inhibit GATA4 expression by binding the 3′UTR of GATA4 mRNA. q-PCR results showed that the expression of miR-122 is negatively correlated with that of GATA4 mRNA transcription. Conclusion These results indicated that miR-122 regulate the expression of GATA4 during the induction of cardiomyocyte-like cells.

Objective Delayed xenograft rejection (DXR) is a major barrier to the long-term xenograft survial.This study evaluated the interaction between human peripheral blood mononuelear cells (PBMC) and porcine endothelial cells (PEC),and the effects of new generation of rabbit antihuman leukocyte polyclonal antibody (newRALG) inhibiting xenogeneic cell-mediated immune responses.Methods newRALG was obtained from rabbits after immunization with activated lymphocytes and monoeytes.PEC were isolated from aorta,and human PBMC were isolated from peripheral blood.Co-cultures of PKH-26 labeled PEC with PBMC were established,newRALG,thymoglobulin,isotype Ig and scavenger receptor (SR) ligand poly G were added into the co-cultures.Cells were collected,then FACS analysis was carried out to detect the up-take of PEC membrane by monocytes and the expression of costimulatory molecules.Lymphocyte proliferative responses to PEC with or without antibody were evaluated by a xenogeneie mixed lymphocyte-endothelial cell reaction (xMLER).Results FACS analysis revealed that monocytes from PBMC-PEC co-cultures became positive for PKH-26 following their interaction with PKH-26 labeled PEC,indicating that they engulfed PEC membranes during activation.PKH-26 positive monocytes up-regulated the CD40 and CD80 expression.Furthermore,SR blockade with poly-G prevented PEC membrane up-take by monocytes,newRALG greatly reduced SR-mediated PEC membrane up-take.The effects of thymoglobulin in inhibiting PEC membrane uptake were limited.xMLER demonstrated strong lymphocyte proliferation in response to PEC,and lymphocyte proliferation was dramatically inhibited by newRALG but not isotype Ig at a dosmdependent manner.Conclusions Monocytes play an important role in xenogeneic immune responses.SR ligand poly G inhibits PEC membrane up-take.newRALG inhibits PEC membrane up-take by monocytes,suggesting that newRALG blocks SR.Additionally,newRALG inhibits lymphocyte proliferation in response to PEC.These results suggest that this new polyclonal preparation may thus impair the initiation of xeno-specific immune responses and prevent xenograft rejection.

Human tumor suppressor gene beclin 1 regulates cell growth through autophagy. The mRNA expression of beclin 1 was reported to be down-regulated in breast cancer with high frequency of loss of heterozygosity (LOH). However, there was no report about the expression levels or the regulatory mechanisms of beclin 1 in gastric and colorectal cancer. Both the mRNA and protein expression levels of beclin 1 was detected in the tissues of gastric and coiorectai cancers, as well as the aberrant DNA methylation and LOH related to the expression of beclin 1. By comparing with normal tissues adjacent to the tissue of these tumors, it was found that beclin 1 mRNA expression levels were significantly decreased in gastric tumor tissue. Furtherly by explorating the 5' region of beclin 1 gene sequence, a large and dense CpG island was discovered and meanwhile methylations in the promoter and the intron 2 regions of beclin 1 were found in both gastric and colorectal tumors. And LOH was found in gastric tumors. These findings suggested that aberrant DNA methylation, as well as LOH, were involved in the regulation of beclin 1 expression in gastric and colorectal cancer.