Objective To analyze the diagnostic utility of combining susceptibility-weighted imaging(SWI)with arterial spin labeling(ASL)in patients with acute ischemic stroke(AIS).Methods Fifty AIS patients who admitted to Yongchuan Hospital,Chongqing Medical University from July 2020 to July 2021 were selected.Scans were performed using a 3.0T MRI scanner,including sequences such as FLAIR,DWI,3D-TOF-MRA,3D-ASL,and SWI.The perfusion status of the infarction core,the grading of draining veins around the infarction core,compensation by collateral circulation,the occurrence of hemorrhagic transformation,and prognosis were assessed.Results The grading of draining veins around the infarction core was significantly correlated with NIHSS scores(r=0.869,P＜0.05)and prognosis(r=0.825,P＜0.05).In addition,significant correlations were found between the perfusion status of the infarction core and the occurrence of hemorrhagic transformation(r=0.873,P＜0.05),compensation by collateral circulation and prognosis(r=0.883,P＜0.05).Conclusion The combination of SWI and ASL provides accurate indications of the hemodynamic conditions around the infarction core in AIS patients,and it can accurately assess the prognosis of AIS patients,contributing valuable information for clinical diagnosis and the selection of treatment strategies.

Objective To evaluate the efficacy of different interventions to the extra cranial lesions in acute ischemic stroke(AIS)due to anterior tandem lesions(TL)on reperfusion.Methods As a multi-center,cross-sectional study,AIS due to anterior TL receiving mechanical thrombectomy(MT)were retrospectively collected.Interventions to the extra-cranial stenosis were recorded.Post-procedural reperfusion was assessed using the modified thrombolysis in cerebral infarction(mTICI)score.Complete revascularization was defined as mTICI 3 and good revascularization was defined as mTICI 2b/3.The relationship between different extra-cranial intervention regi-mens and rate of re-vascularization was compared.Results Totally 117 patients were included with 92.3% reaching good recanalization and 63.2% reaching complete re-canalization.There was no significant difference in good re-canalization rates among various extra-cranial intervention regimens.The rate of complete re-canalization was significantly higher in patients receiving endovascular therapy(P＜0.05)and there was significant difference among various endovascular treatment regimens(P＜0.01):acute balloon angioplasty only group presented the highest rate of complete re-canalization(100.0% ),followed by acute stenting only group(80% ),acute stenting+balloon angioplasty group(73.7% )and conservative treatment group(54.3% ).Conclusions Endovascular inter-vention to extra-cranial stenosis contributes to complete re-canalization in AIS due to anterior TL receiving MT,and acute balloon angioplasty seems to be quite effective than acute stenting.

Objective:To prepare the chitin/hyaluronic acid/collagen hydrogel loaded with mouse adipose-derived stem cells and to explore its effects on wound healing of full-thickness skin defects in rats.Methods:The research was an experimental research. Chitin nanofibers were prepared by acid hydrolysis and alkaline extraction method, and then mixed with hyaluronic acid and collagen to prepare chitin/hyaluronic acid/collagen hydrogels (hereinafter referred to as hydrogels). Besides, the hydrogels loaded with mouse adipose-derived stem cells were prepared. Thirty male 12-week-old guinea pigs were divided into negative control group, positive control group, and hydrogel group according to the random number table, with 10 guinea pigs in each group. Ethanol, 4-aminobenzoic acid ethyl ester, or the aforementioned prepared hydrogels without cells were topically applied on both sides of back of guinea pigs respectively for induced contact and stimulated contact, and skin edema and erythema formation were observed at 24 and 48 h after stimulated contact. Adipose-derived stem cells from mice were divided into normal control group cultured routinely and hydrogel group cultured with the aforementioned prepared hydrogels without cells. After 3 d of culture, protein expressions of platelet-derived growth factor-D (PDGF-D), insulin-like growth factor-Ⅰ (IGF-Ⅰ), and transforming growth factor β 1 (TGF-β 1) were detected by Western blotting ( n=3). Eight male 8-week-old Sprague-Dawley rats were taken and a circular full-thickness skin defect wound was created on each side of the back. The wounds were divided into blank control group without any treatment and hydrogel group with the aforementioned prepared hydrogels loaded with adipose-derived stem cells applied. Wound healing was observed at 0 (immediately), 2, 4, 8, and 10 d after injury, and the wound healing rate was calculated at 2, 4, 8, and 10 d after injury. Wound tissue samples at 10 d after injury were collected, the new tissue formation was observed by hematoxylin-eosin staining; the concentrations of interleukin-1α (IL-1α), IL-6, IL-4, and IL-10 were detected by enzyme-linked immunosorbent assay method; the expressions of CD16 and CD206 positive cells were observed by immunohistochemical staining and the percentages of positive cells were calculated. The sample numbers in animal experiment were all 8. Results:At 24 h after stimulated contact, no skin edema was observed in the three groups of guinea pigs, and only mild skin erythema was observed in 7 guinea pigs in positive control group. At 48 h after stimulated contact, skin erythema was observed in 8 guinea pigs and skin edema was observed in 4 guinea pigs in positive control group, while no obvious skin erythema or edema was observed in guinea pigs in the other two groups. After 3 d of culture, the protein expression levels of PDGF-D, IGF-I, and TGF-β 1 in adipose-derived stem cells in hydrogel group were significantly higher than those in normal control group (with t values of 12.91, 11.83, and 7.92, respectively, P<0.05). From 0 to 10 d after injury, the wound areas in both groups gradually decreased, and the wounds in hydrogel group were almost completely healed at 10 d after injury. At 4, 8, and 10 d after injury, the wound healing rates in hydrogel group were (38±4)%, (54±5)%, and (69±6)%, respectively, which were significantly higher than (21±6)%, (29±7)%, and (31±7)% in blank control group (with t values of 3.82, 3.97, and 4.05, respectively, Pvalues all <0.05). At 10 d after injury, compared with those in blank control group, the epidermis in wound in hydrogel group was more intact, and there were increases in hair follicles, blood vessels, and other skin appendages. At 10 d after injury, the concentrations of IL-1α and IL-6 in wound tissue in hydrogel group were significantly lower than those in blank control group (with tvalues of 8.21 and 7.99, respectively, P<0.05), while the concentrations of IL-4 and IL-10 were significantly higher than those in blank control group (with tvalues of 6.57 and 9.03, respectively, P<0.05). The percentage of CD16 positive cells in wound tissue in hydrogel group was significantly lower than that in blank control group ( t=8.02, P<0.05), while the percentage of CD206 positive cells was significantly higher than that in blank control group ( t=7.21, P<0.05). Conclusions:The hydrogel loaded with mouse adipose-derived stem cells is non-allergenic, can promote the secretion of growth factors in adipose-derived stem cells, promote the polarization of macrophages to M2 phenotype in wound tissue in rats with full-thickness skin defects, and alleviate inflammatory reaction, thereby promoting wound healing.

Objective:To explore the potential of thrombus-targeted nanoprobes for ultrasound/near-infrared bimodal imaging and their synergistic therapeutic effects on thrombosis in vitro.Methods:Nanoprobes loaded with arginine-glycine-aspartate peptide (RGD), perfluoropentane (PFP) and indocyanine green (ICG) were prepared by ultrasonic vibration and carbodiimide method with mesoporous silica nanoparticle (MSN) as the carrier. The probe morphology was observed by scanning and transmission electron microscopy. The loading of RGD and ICG was detected by Bicinchoninic Acid Assay (BCA) and UV-Visible-NIR spectroscopy respectively. The imaging performance and photothermal response of the nanoprobe under near infrared light (NIR) irradiation were studied in vitro. Its biological safety was tested by cytotoxicity test and hemolysis test. The phase transformation was studied under ultrasound and NIR irradiation. The nanoprobe was incubated with fresh arterial thrombus, and its target-seeking ability was observed by frozen section. Ultrasound and NIR irradiation were used to evaluate its thrombolytic ability by the weight changes of thrombus before and after irradiation.Results:The prepared nanoprobe had regular morphology and uniform size. The particle diameter was (156.83±5.05)nm, and the surface potential was (11.47±0.25)mV. The RGD coupling rate was (77.67±4.50)%, which could mediate the targeting of nanoprobe to fresh extracorporeal arterial thrombus. UV-Visible-NIR spectroscopy confirmed the successful loading of ICG, and its encapsulation rate was (80.47±0.05)%. After ultrasound and NIR irradiation, the nanoprobe could undergo acoustically induced phase transition, thermally induced phase transition and enhance the ultrasonic development effect. With the increase of the concentration of the nanoprobe solution, the NIR signal gradually increased, and the temperature rose in a concentration-dependent and intensity-dependent manner after NIR irradiation. The cytotoxicity test and hemolysis test showed that the nanoprobe had good biological safety, and it could play a thrombolytic role under the combined irradiation of ultrasound and NIR, and the weight of thrombus was significantly reduced after the treatment ( P<0.01). Conclusions:In this study, the nanoprobe (RGD/ICG/PFP@MSN) were successfully prepared possesses excellent dual mode imaging capabilities of ultrasound and NIR, excellent phase transition ability and photothermal conversion efficiency, as well as efficient targeted penetration and therapeutic effects against thrombosis. This study provides strong in vitro experimental evidence and new strategies for the integration of diagnosis and treatment of thrombotic diseases under the cooperation of ultrasound and NIR.

Objective:To explore the clinicalfactors related to allograft fibrosis after pediatric liver transplantation.Methods:The clinical data were respectively analyzed for 94 pediatric recipients from January 2013 to December 2016 at Tianjin First Central Hospital.The Patients were assigned into fibrotic and non-fibrotic groups based upon the results of protocol liver biopsies. Univariate and multivariate Logistic regression analyses were performed for examining the risk factors of fibrosis after pediatric livertransplantation. Then Logistic regression model was established to obtain the predicted value of combined predictive factors.Thereceiver operating characteristic curve (ROC) was conducted to evaluate the predictive value of combined predictive factors.Results:A total number of 54(57.5%) patients occurred fibrosis among the 94 patients. There weresignificant differences in cold ischemia time (Z=2.094), warm ischemia time (Z=2.421), biliary stricture( χ2=4.560), drug-induced liver injury ( χ2=7.389), hepatic artery thrombosis and rejection ( χ2=6.955)between two groups ( P<0.05). Logistic regression analysis showed that cold ischemia time (OR=1.003, 95%CI: 1.000~1.007, P=0.044), biliary stricture(OR=6.451, 95%CI: 1.205~33.295), rejection(OR=2.735, 95%CI: 1.057~7.077)and drug-induced liver injury (OR=4.977, 95%CI: 1.207~20.522, P=0.026) were independent risk factors for fibrosis 5 years after liver transplantation. The area under the ROC curve was 0.786(95%CI: 0.691~0.881), for predicting patient outcome.If using 0.311as a cutoff Value, the sensitivity was 90.70%, and the specificity was 60.00%. However, through the ROC curve comparison, there was statistical significance between combined predictive factors and the other independent risk factors ( P>0.05). Conclusions:The incidence of fibrosis 5 years after pediatricliver transplantation is 57.5%. Prolonged cold ischemia time, biliarystricture, rejectionand drug-induced liver injury after liver transplantation are independent risk factors for fibrosis 5 years after pediatric liver transplantation.And the combined predictive factors have a high predictive value forallograftfibrosis.

Objective The purpose of this study is to grasp the current situation of radiation protection in some non-medical institutions in Hangzhou, and to provide basis and reference for the relevant authorities departments to make the radioactive hazard factors monitoring plan for non-medical institutions. Methods The configuration of the personnel protective equipment and radiation level of radiation sources and radiation devices in 5 non-medical monitoring institutions in Hangzhou were investigated and analyzed by means of questionnaire survey and on-site detection. Results The radiation workers of 5 monitoring institutions have carried out personal dose monitoring, and their annual individual dose equivalent meets the requirements of relevant national standards. The ambient dose equivalent rates around the radiation source and radiation device room are lower than the minimum detection limit of the instrument. When the source is stored, the maximum ambient dose equivalent rates at 5 cm and 100 cm away from the external surface of the source container were 22.2 μSv/h and 2.0 μSv/h, respectively. When the source is in use, the maximum ambient dose equivalent rates at 5 cm and 100 cm away from the external surface of the source container were 44.3 μSv/h and 5.0 μSv/h, respectively. Conclusion Under normal operation, the radiation dose level of some non-medical monitoring institutions in Hangzhou is at a low level, while the ambient dose equivalent rates around the external surface of the source container is at a high level. Therefore, non-medical institutions should improve their awareness of radiation protection and strengthen radiation management.

OBJECTIVE: To investigate the effect of orthodontic traction on the microstructure of dental enamel. METHODS: Forty-eight isolated premolars were randomly divided into 6 groups (=8), including Group A (blank control group), in which the teeth were bonded with the orthodontic brackets without any loading force; Groups B1, B2, and B3 where the teeth were bonded with the orthodontic brackets using clinical adhesives and loaded with 50 g force for 6 months, 200 g force for 6 months, and 200 g force for 1 month, respectively; and Groups C1 and C2, where the teeth were bonded with straight wire brackets using light curing bonding and chemical curing bonding techniques, respectively. All the teeth were embedded with non-decalcified epoxy resin. Scanning electron microscope (SEM), atomic force microscope (AFM), and energy spectrometer (EDS) were used to analyze interface morphology and elemental composition of the teeth sliced with a hard tissue microtome. RESULTS: Compared with those in Group A, the teeth in the other 5 groups showed increased adhesive residue index with microcracks and void structures on the enamel surface under SEM; AFM revealed microcracks on the enamel surface with angles to the grinding direction. A larger loading force on the bracket resulted in more microcracks on the enamel interface. The interface roughness differed significantly between Groups A and C2, and the peak-to-valley distance differed significantly between Groups A, C, and C2. CONCLUSIONS Orthodontic traction can cause changes in the microstructure of normal dental enamel.
Dental Enamel ; Materials Testing ; Orthodontic Brackets ; Resin Cements ; Surface Properties ; Traction

Objective To understand the status of type 2 diabetes mellitus (T2DM) patients′ trust in their family physicians, and to explore the role of the trust on patients′ medication adherence. Methods A total of 1078 patients with T2DM were recruited by cluster and systematic sampling method, from ten rural communities in Sanlong township in Yancheng city and five rural communities of Pingchao township in Nantong city, during February to April in 2018. The survey covered their trust behavior and attitude scale (PTBAS), and an 8-item Morisky medication adherence scale ( MMAS-8). Both measurement data and enumeration data were subject to descriptive analysis by mean ± SD and proportion respectively. Multiple linear regression was employed to explore the determinants of trust in physicians. Ordered logistic regression analysis was used to explore the relationship between patient-physician trust and medication adherence. Results The mean scoring of patients′ trust and medication adherence was 20. 16 ± 2. 13, 7. 07 ± 1. 54 respectively. 55. 40 percent of the patients had high medication compliance, 28. 53 percent of them had medium compliance and 16. 07 percent had poor compliance. Multiple linear regression analysis showed that the patient′s occupation, course of disease, self-reported health status and mental health status influenced their trust behavior (P < 0. 05). Ordered logistic regression analysis showed that each 1 point increase in patient′s trust in physicians, the medication compliance increased by 11. 0％ (OR = 1. 110, P < 0. 001). Medication adherence is also affected by age, employment status, course of illness, and mental health status. Conclusions Diabetes patients′ trust in their family physicians improves their medication adherence.

Objective? To develop a nurse-patient communication process for patient with cancer in China based on the American CICARE communication model and to provide standardized and processed guidance for communication between clinical nurses and cancer patients. Methods? Totally 5 clinical nursing experts from a Class Ⅲ Grade A hospital in Beijing were selected by purposive sampling and interviewed using focus group discussion between November and December 2018. Results? The nurse-patient communication process was developed based on the CICARE communication model after two rounds of focus group discussions, whose six steps were polite connection, complete introduction, professional explanation, careful asking, patient response and proper exit, which included role adaptation of nurses, admission evaluation, coordination during hospitalization, case management, care and health education. Conclusions? A nurse-patient communication process for cancer patients in China is developed using nurse-patient communication models from other countries and clinical nursing practice for reference, which provides a reference for nurse-patients communication and lays a foundation for carrying out the optimal nursing service demo projects and refined management.

To combine more than 20 years of experience in clinical practice skills teaching of laboratory medicine, with the characteristics of laboratory medicine, the theory system of formative assessment has been constructed, to guide the clinical practice of the students.Based on the construction of network question bank, students make use of the network question bank self testing, to know whether they had got the stage goal, existing problems and future plan through self testing, so as to mobilize their enthusiasm and initiative to enhance their self-confidence.Under the formative assessment teaching system, students establish internship file information, including practice notes, weekly practice, group discussion, self testing results, the teacher and peer assessment information.Teachers set up QQ group, WeChat group with their students, the timely to get the question from students and to take appropriate measures improve teaching.Teachers had established and improved the long-term after graduation feedback mechanism, and formative assessment improved the teaching quality of the whole practice teaching benefits teachers as well as students.