Objective:To investigate the effects of Bruner's constructivist theory on the critical thinking and practice performance of nursing students interning in internal medicine.Methods:One hundred and fifty-three undergraduate nursing students practicing in the department of internal medicine of a Beijing grade A tertiary hospital were selected by convenience sampling and divided into control group ( n=76) and experimental group ( n=77) according to the order of rotation time. The experimental group received teaching based on Bruner's constructivist theory, while the control group was given traditional teaching. SPSS 24.0 was used to perform the t test. Results:Compared with the control group, the experimental group showed a significantly higher critical thinking score [(306.13±33.00) vs. (325.03±32.09)], a significantly higher exit theory assessment score [(94.74±3.24) vs. (96.94±1.79)], a significantly higher exit skills assessment score [(86.68±11.95) vs. (90.23±9.17)], and a significantly higher degree of satisfaction with teaching [(180.08±13.35) vs. (187.91±14.50); all P<0.05]. Conclusions:Bruner's constructivist theory can help nurse students improve their critical thinking, theoretical and practical performance, and satisfaction with teaching, which enhances the effects of internal medicine nursing teaching.

Objective:To explore the clinical efficacy of double opposing rhomboid flap in repairing facial skin defects.Methods:From January 2020 to December 2020, 30 cases of facial skin lesions were removed in the Department of Plastic and Aesthetic Surgery, the Affiliated Hospital of Qingdao University, including 12 males and 18 females, aged 14-65 years, with an average age of 34.2 years. The diameter of the facial skin defect wound was 0.5-2.0 cm. The patients with facial skin defect were repaired with double opposing rhomboid flap. All patients were followed up for 3-12 months.Results:The incisions of 30 patients were healed in one stage, and double opposing rhomboid flaps survived. Following-up for 3 to 12 months showed that the operation area was flat, the incision scar was not obvious, the texture and color of the operation area and the surrounding skin matched well, the surrounding organs were not deformed, the lesions were not recurrent, and the cosmetic effect was satisfactory.Conclusions:The double opposing rhomboid flap is an effective method to repair quasi-circular facial skin defects, which is worthy of clinical application.

Objective:To examine the effects of apelin-13 on ferroptosis of the C2C12 skeletal muscle cell line induced by a high-iron environment and explore potential underlying mechanisms.Methods:C2C12 cells were cultured in Dulbecco's Modified Eagle Medium(DMEM)and divided into a control group, a ferric citrate(FAC)group, an apelin-13 group, an FAC+ apelin-13 group, a ferroptosis inducer RSL3 group and an FAC+ apelin-13+ RSL3 group.Cell viability was detected by the 3-(4, 5-dimethyl thiazole-2)-2, 5-diphenyl thiazolyl blue(MTT)assay.The intracellular concentrations of total iron and divalent iron were measured by colorimetry; the levels of glutathione(GSH), malondialdehyde(MDA)and intracellular reactive oxygen species(ROS)in cells were detected by an enzyme-linked immunosorbent assay, visible spectrophotometry and a chemifluorescence method, respectively.The ultrastructure of C2C12 cells was examined by transmission electron microscopy.The protein expression of glutathione peroxidase 4(GPX-4), ferritin heavy chain 1(FTH-1), heme oxygenase 1(HO-1)and nuclear factor E2-related factor 2(Nrf-2), were detected by Western blotting.Results:Compared with the FAC group, the FAC+ Apelin-13 group had significantly elevated cell viability(optical density: 0.52±0.06 vs.0.28±0.04, t=7.837, P=0.007)and higher concentrations of GSH(2.41±0.35 vs.0.91±0.12 μmol/g Pro, t=9.778, P=0.003), but significantly decreased levels of ROS(22.06±5.79 vs.52.71±7.28 a. u./mg Pro, t=8.064, P=0.006), MDA(4.63±0.51 vs.9.11±0.84 mmol/mg Pro, t=8.642, P=0.006), total iron(1.53±0.24 vs.3.17±0.55 μmol/g Pro, t=6.135, P=0.013)and divalent iron(0.75±0.08 vs.1.94±0.36 μmol/g Pro, t=5.068, P=0.027), as well as reduced intracellular iron deposition.In the control group and the apelin-13 group, the morphology of the mitochondria was clear and normal.In contrast, the mitochondria in the FAC group had increased membrane density, membrane shrinkage and rupture, vacuolar degeneration, and obvious mitochondrial damage, which were consistent with the morphological characteristics of ferroptosis.Compared with the FAC group, the FAC+ apelin-13 group showed significant improvement in mitochondrial damage.Moreover, compared with the FAC+ apelin-13 group, the cell viability of the FAC+ apelin-13+ RSL3 group was significantly decreased(optical density: 0.23±0.04 vs.0.48±0.06, t=7.642, P=0.007). Compared with the FAC group, the FAC+ apelin-13 group had significantly up-regulated cellular expression of GPX-4(relative expression: 0.96±0.14 vs.0.31±0.07, t=7.712, P=0.008), FTH-1(0.57±0.08 vs.0.27±0.05, t=6.944, P=0.011), and HO-1(0.49±0.07 vs.0.28±0.05, t=6.472, P=0.012), as well as increased nuclear expression of Nrf-2(relative expression: 0.42±0.04 vs.0.19±0.05, t=7.114, P=0.008)with a higher ratio of nuclear expression over total cellular expression[(58.36±5.24)% vs.(36.58±5.32)%, t=5.858, P=0.015]and a higher level of HO-1 protein expression(relative expression: 0.49±0.07 vs.0.28±0.05, t=6.472, P=0.012). Conclusions:Apelin-13 inhibits ferroptosis induced by a high iron environment in C2C12 cells, and the underlying molecular mechanisms may be related to the Nrf-2/HO-1 signaling pathway.

Beijing ; COVID-19 ; Contact Tracing ; Humans ; Risk Factors ; SARS-CoV-2

Objective:To observe the effect of Apelin-13 on diabetes-related sarcopenia in rats model and explore the underlying mechanism.Methods:This experiments were divided into 3 groups.In the normal control group, Wistar rats were fed by ordinary feed, intraperitoneally injected daily with the equal amount of normal saline.In the model+ control group, diabetic-related sarcopenia model was established in rats with fat-fed Goto-Kakizaki rats for 12 weeks and intraperitoneally injected daily with the equal amount of normal saline.In the model+ apelin-13 group, apelin-13(0.1 mol/kg)was intraperitoneally injected into diabetic-related sarcopenia model daily for 12 weeks.The water intake, food intake, and body weight were measured.The fasting blood glucose, fasting insulin and blood lipid levels of rats were measured, and the insulin resistance index was calculated.The wet weight of the rats' gastrocnemius muscle was weighed, and the morphological changes of the gastrocnemius muscle were observed.Western blot was used to detect the protein expressions of phosphatidylinositol-3 kinase(PI3K)and phosphorylated Akt(p-Akt)in the gastrocnemius muscle of rats.Results:Compared with the model+ normal saline group, the model+ apelin-13 group showed that the following parameters were significantly improved.(1)The water intake of rats was significantly decreased at 8, and 12 weeks( F=7.17 and 7.91), and food intake was significantly decreased( F=5.84 and 6.12)and body weight were significantly increased at 8 and 12 weeks( F=5.76 and 6.07)(all P<0.05). (2)The levels of fasting blood glucose were significantly decreased at 8 and 12 weeks( F=8.07 and 8.24, all P<0.05). (3)Serum triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, the levels fasting insulin and the insulin resistance index were significantly decreased at week 12( F=5.17, 7.94, 10.27, 8.32, 6.94 and 11.31, all P<0.05); (4)The wet weight of gastrocnemius muscle was significantly increased(0.63±0.04 g and 1.02±0.05 g, t=4.32, P<0.05). (5)Compared with the model+ normal saline group, the model+ apelin-13 group showed the protein expressions of PI3K and p-Akt in the gastrocnemius muscle of rats were significantly up-regulated( t=7.32, 8.07, both P<0.05). Conclusions:Apelin-13 has an inhibitory effect on diabetes-related sarcopenia, and its mechanism may be related to the up-regulation of PI3K and p-Akt expression in skeletal muscle.

Objective: To learn the epidemiological characteristics of fall mortality among the elderly people in Taizhou，and to provide basis for intervention strategies of fall in the elderly. Methods: Data of fall mortality among residents aged 60 years or over in Taizhou from 2016 to 2018，collected from Zhejiang Chronic Disease Surveillance Information Management System，was used for analysis of time，population and geographical characteristics of fall deaths. The epidemic trend of fall mortality in the elderly was described by annual percentage change（APC）. Results: From 2016 to 2018，3 699 cases of fall death in Taizhou were reported，the crude and standardized mortality were 116.90/100 000 and 97.88/100 000. The standardized mortality of fall in women was 106.11/100 000，which was higher than 90.13/100 000 in men（P<0.05）. The standardized mortality of fall in rural residents was 131.20/100 000，which was higher than 28.15/100 000 in urban residents（P<0.05）. The mortality of fall in residents aged 65-69 years from 2016 to 2018 showed an upward trend（APC=4.20%，P<0.05），while the mortality trend of fall in other age groups was not statistically significant（P>0.05）. Conclusion Fall was the first cause of injury death in the elderly aged 60 years or over in Taizhou. Females and rural residents have relatively higher fall mortality.

Objective:To evaluate the effects of shade and light irradiation condition on the polymerization of composite resin core material.Methods:The light-proof silicon rubber cuboid mold with one end open were stringed and filled by dual-cured flowable composite resin core material with the shade of dentine and white(Paracore) respectively,then the open end of mold was irradiated directly by a light unit at 1 000 mW/cm2 ×20 s and 3 200 mW/cm2 ×6 s respectively.And all specimens of 4 groups(n =5) were stored in the light-proof box.1 h and 24 h after irradiation,Knoop microhardness was measured along the vertical surfaces of the specimens at the depth of 1,2 and 3 mm respectively.Data were analyzed by One-way ANOVA.Results:At all light irradiation conditions,the hardness of all specimens decreased with the increase of measurement depth.24 h after irradiation,the hardness of dentine shade specimens at each measurement depth showed no difference between 1 000 mW/cm2 × 20 s and 3 200 mW/cm2 × 6 s irradiation,while the white shade specimens irradiated by 1 000 mW/cm2 × 20 s showed higher hardness than those by 3 200 mW/cm2 × 6 s.Conclusion:To obtain sufficient polymerization of composite core material with different shade optimal light irradiation condition should be selected.

OBJECTIVEThis study aims to identify the effects of corticotomy-assisted orthodontic premolar intrusion andevaluate the changes of root resorption and the alveolar bone.

METHODSBoth sides of the mandible of eight male Beagle dogswere randomly assigned into experimental and control groups. The third (P3) and fourth (P4) premolars were intruded withboth mini-screw implant anchorage (MIA) and corticotomy on the experimental side. By contrast, P3 and P4 were intrudedwith MIA alone on the control side. During pre-operation and after 2, 4, 8, and 12 weeks of orthodontic force applications,cone beam computed tomography was performed on every dog. The distance of tooth intrusion and root resorption of furcation, as well as the apex and height changes of the alveolar bone were measured and analyzed.

RESULTSThe intrusion distanceof premolars on the experimental side was greater than that on the control side (P < 0.05). The root of furcation and apex onboth sides occurred in root resorption, and the root resorption of the apex on the experimental side was lighter than that onthe control side after 12 weeks of force application (P < 0.05). The alveolar bone height decreased, and the height reductiondistance on the experimental side was greater than that on the control side after 8 and 12 weeks of force application (P < 0.05).

CONCLUSIONCorticotomy accelerates orthodontic molarintrusion and reduces root resorption.

Animals ; Bicuspid ; anatomy & histology ; Bone Screws ; Cone-Beam Computed Tomography ; Dogs ; Male ; Mandible ; Root Resorption ; Tooth Movement Techniques ; Tooth Root

Objective To investigate the value of MRI in the prenatal diagnosis of abnormal fetal kidneys. Methods From December 2014 to March 2016, 51 women underwent MRI and were confirmed as having fetuses with abnormal fetal kidneys when follow up. Their clinical and MRI profiles were analyzed retrospectively, including MRI manifestation, the fetal kidney signal intensity of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC). The signal intensity of DWI and ADC of the abnormal kidney and the normal opposite kidney, and those of the normal and abnormal kidneys in different individuals were compared. The accuracies of MRI and ultrasound in evaluating abnormal fetal kidneys were also compared. Results MRI could accurately demonstrate the morphological features of abnormal fetal kidneys. There was no statistically significant difference between DWI signal intensity and ADC value of the abnormal kidney[368 ± 125,(1.516 ± 0.420)× 10-3 mm2/s] and the normal opposite one[410 ± 125,(1.362 ± 0.251)× 10-3 mm2/s], P values were 0.165 and 0.184,respectively. The DWI signal intensity of normal kidneys(401 ± 124)was higher than that of renal cysts(182 ± 40, P<0.01), and the ADC value of normal kidneys[(1.306 ± 0.252)× 10-3 mm2/s] was lower than that of renal cysts[(2.912 ± 0.235)× 10-3 mm2/s] and multicystic dysplastic kidneys[(1.870 ± 0.654)× 10-3 mm2/s], P values were<0.01 and 0.045, respectively. The diagnostic accuracy of MRI and prenatal ultrasound for abnormal fetal kidneys were 94%(63/67)and 85%(57/67), respectively. However, there was no statistical difference between the two methods (P=0.070). Conclusion MRI have an important role in the prenatal diagnosis and evaluation of abnormal fetal kidneys.

OBJECTIVETo explore the feasibility of preparation of a mouse model of orthotopic colon cancer by injecting tumor cell suspension into mesenteric triangle of the cecum.

METHODSTwenty SPF 8-week old BALB/c mice (male:female = 1:1) were used in this study. The mouse caecum was exposed by laparostomy, and suspension of mouse colon adenocarcinoma CT26. WT cells was injected into the mesenteric triangle of cecum for preparation of a mouse model of orthotopic colon cancer.

RESULTSMouse orthotopic colon cancer was developed by injection of tumor cell suspension into mesenteric triangle of the cecum showing a successful rate of 100%, without intestinal obstruction, and the liver, spleen, diaphragm and mesenteric lymph nodes metastasis rates were high in all the 20 experimental mice.

CONCLUSIONSThe establishment of mouse models of orthotopic colon cancer by injection of tumor cell suspension into the mesenteric triangle is a simple, rapid, and easy to master procedure, causing less damage to the colon wall, safe and with less trauma to the mice. This method may provide an ideal mouse model of orthotopic colon cancer for the study of pathogenesis as well as liver metastasis mechanisms of colon cancer.

Adenocarcinoma ; pathology ; secondary ; Animals ; Cecal Neoplasms ; pathology ; Cecum ; Colonic Neoplasms ; pathology ; Disease Models, Animal ; Feasibility Studies ; Female ; Liver Neoplasms ; secondary ; Lymphatic Metastasis ; Male ; Mice ; Mice, Inbred BALB C ; Neoplasm Transplantation ; methods