ObjectiveTo explore the effectiveness and advantage of three-dimensional (3D) printing technology in treatment of internal or external ankle distal avulsed fracture.MethodsBetween January 2015 and January 2017, 20 patients with distal avulsed fracture of internal or external ankle were treated with the 3D guidance of shape-blocking steel plate fixation (group A), and 18 patients were treated with traditional plaster external fixation (group B). There was no significant difference in gender, age, injury cause, disease duration, fracture side, and fracture type between 2 groups (P>0.05). Recording the fracture healing rate, fracture healing time, the time of starting to ankle functional exercise, residual ankle pain, and evaluating ankle function recovery of both groups by the American Orthopaedic Foot and Ankle Society (AOFAS) score.ResultsAll patients were followed up 8-24 months, with an average of 15.5 months. In group A: all incisions healed by first intention, the time of starting to ankle functional exercise was (14±3) days, fracture healing rate was 100%, and the fracture healing time was (10.15±2.00) weeks. At 6 months, the AOFAS score was 90.35±4.65. Among them, 13 patients were excellent and 7 patients were good. All patients had no post-operative incision infection, residual ankle pain, or dysfunction during the follow-up. In group B: the time of starting to ankle functional exercise was (40±10) days, the fracture healing rate was 94.44%, and the fracture healing time was (13.83±7.49) weeks. At 6 months, the AOFAS score was 79.28±34.28. Among them, 15 patients were good, 2 patients were medium, and 1 patient was poor. During the follow-up, 3 patients (16.67%) had pain of ankle joint with different degrees. There were significant differences in the postoperative fracture healing rate, fracture healing time, the time of starting to ankle functional exercise, and postoperative AOFAS score between 2 groups (P<0.05).ConclusionApplication of 3D printing technology in treatment of internal or external ankle distal avulsed fracture is simple, safe, reliable, and effective. In particular, it is an ideal treatment for avulsed fracture.
Objective To elucidate the etiology of DNA impairment of type Ⅱ alveolar epithelial cells(AT-II) of the rats fed with low selenium and high cadmium fodder，and the effect of Vitamin C.Methods With single cell gel electrophoresis technique，we observed the joint action of selenium，cadmium and vitamin C on DNA damage in AT-II cells of the eight groups of rats fed separately with：normal （2 groups），high Cd，high Cd+high VC，low Se+high Cd，low Se+high Cd+high VC，high Se+high Cd and high Se+high Cd+high VC fodder for 14 weeks.Results Compared with the control，there was no DNA changes have been observed in the high Se+high Cd+high VC group.However，in the high Se+high Cd group and high Cd+high VC group，DNA damage of AT-II cells can be detected clearly；in the low Se+high Cd+high VC group and high Cd group，the degree of the DNA damage is more serious than the above two groups；in the low Se+high Cd group，the extent of the DNA damage was the most serious on all of the groups be studied.Conclusion It is suggested that Se deficiency and simultaneously Cd overabundance may damaged DNA of AT-II cells of the rats significantly，however，Vitamin C may protect AT-II against the injury effectively.
Objective To investigate the expression and significance of Krüppel-like factor 4 ( KLF4) in the lung tissues of mice with bleomycin-induced pulmonary fibrosis.Methods C57BL/6 mice were randomly divided into a control group and a BLM group. The mice in the BLM group were given a single intratracheal injection of bleomycin ( 2.5 mg/kg) , while those in the control group were injected with isodose physiological saline. The mice were sacrificed at the 12h and on the day 1, 2, 3, 7, 14 and 28, then HE stain and Masson’s trichrome stain were used to detect the architecture of alveolar and the deposition of cellularity and collagen. Real time-polymerase chain reaction ( RT-PCR ) and immunohistochemical technology were performed to investigate the expression of KLF4. Results In the bleomycin-induced pulmonary fibrosis, acute inflammation was observed on the day 1, 2 and 3, the inflammation was exacerbated and the collagen deposition began to be observed on the day 7, the architecture of alveolar was destroyed and the collagen deposition was more obvious on the day 14, while the alveolar structure was nearly recovered to normal, and the inflammation and collagen deposition were attenuated on the day 28. The expression of KLF4 mRNA increased from the day 1, then decreased, arrived at the minimumon the day 3, and then gradually increased until the day 28. The trend of KLF4 protein expression showed roughly the same as the KLF4 mRNA level, which started to increase on the day 1, then decreased, arrived at the minimum on the day 3,then gradually increased until the day 14 and then decreased again. Conclusion The expressions of KLF4 mRNA and protein are dynamically changed in the process of experimental pulmonary fibrosis, suggesting KLF4 may contribute to the pathogenesis of pulmonary fibrosis.
ObjectiveTo investigate the effects and mechanism of atorvastatin in the experimental pulmonary fibrosis. MethodsFifty-four C57BL/6 mice were randomly divided into a control group,a bleomycin group and an atorvastatin group. The mice in the bleomycin group and the atorvastatin group received a single dose intratracheal injection of bleomycin (2.5 mg/kg),while the mice in the control group were injected with isodose physiological saline. The mice in the atorvastatin group were treated with atorvastatin 10 mg·kg-1·d-1 by intragastric administration the day after bleomycin instillation. All groups were sacrificed on the day 3,14 and 28,respectively. HE staining and Masson staining were used to detect the architecture of alveolar and the deposition of cellularity and collagen. RT-PCR and immunohistochemical technology were performed to detect the expression of Krüppel like factor 4 (KLF4). Zymography was used to investigate the activation of matrix metalloproteinase-2(MMP-2). ResultsAfter the treatment of bleomycin,the lung tissues showed acute inflammation on the day 3,the collagen deposition was more obvious and the architecture of alveolar was destroyed on the day 14. The alveolar structure,the inflammation and collagen deposition were attenuated on the day 28 compared with the day 14. Compared with the bleomycin group,the inflammation and the collagen deposition were significantly reduced in the atorvastatin group (P<0.05). Compared with bleomycin group,the expression of KLF4 significantly decreased in the atorvastatin group,although the expression of KLF4 mRNA increased on the day 3 compared with the bleomycin group (0.502±0.261 vs. 0.326±0.164,P<0.05). The expression of KLF4 protein on the day 3 was significantly decreased compared with the bleomycin group (0.048±0.015 vs. 0.130±0.017,P<0.05). After the intervention of bleomycin,the activation of MMP-2 on the day 3 and 14 significantly increased compared with the control group (3.136±1.321 and 3.449±0.356 vs. 0.983±0.147,P<0.05),and significantly decreased after the treatment of atorvastatin (2.191±0.800 and 2.506±0.761). ConclusionAtorvastatin may have anti-inflammation and anti-fibrosis activities in experimental pulmonary fibrosis through KLF4 pathway.
ObjectiveTo develop a new type of internal fixation device which can be used to treat the minor avulsion fracture of the medial malleolus, lateral malleolus, the base of the fifth metatarsal, and the ulnar styloid process, and investigate the reliability and effectiveness of the device through biomechanical test.MethodsEighty human’s bone specimens with complete medial malleolus, lateral malleolus, the base of the fifth metatarsal, and the ulnar styloid process were selected and measured the anatomic indexes (the height, width, and thickness of medial malleolus, lateral malleolus, the base of the fifth metatarsal, and the ulnar styloid process). The CT three-dimensional reconstruction data of 200 healthy adults which including medial malleolus, lateral malleolus, the base of the fifth metatarsal, and the ulnar styloid process was also selected and measured the anatomic indexes by Mimics software. The plastic rod-hook plate was designed according to the measured results and prepared. Forty fresh porcine lower limb specimens were randomly divided into groups A and B (20 in each group), and 8 adult lower limb specimens including 4 left and 4 right were also randomly divided into groups A and B (4 in each group). All specimens were prepared for avulsion fracture of medial malleolus. Then, the fractures were fixed with plastic rod-hook plate in group A and wire anchor in group B. The load and axial torsion test of ankle joint were carried out by universal biomechanical testing machine.ResultsAccording to the anatomical characteristics, a plastic rod-hook plate was designed successfully. The biomechanical test results between animal and human specimens were consistent. There was a linear relationship between load and displacement in the ankle distal load test. The displacement when loaded to the maximum load was significantly lower in group A than in group B (P<0.05). The torsion angle and torque were significantly higher in group A than in group B when the internal fixation failed in the axial torsion test of the ankle joint (P<0.05), and the torsion angle was significantly smaller in group A than in group B when the torque was 1 N·m (P<0.05), and the maximum torque was also significantly higher in group A than in group B (P<0.05). However, there was no significant difference in torsion angle between the two groups in the maximum torque (P>0.05).ConclusionThe biomechanical properties of plastic rod-hook plate is obviously better than wire anchor, and the fixation of avulsion fracture with plastic rod-hook plate is easy to operate, which is expected to be used in the clinical treatment of minor avulsion fractures such as medial malleolus, lateral malleolus, base of the fifth metatarsal, and ulna styloid process.
ObjectiveTo investigate the current situation of stress load and professional benefit of hemodialysis nurses during the outbreak period and the remission period of coronavirus disease 2019 (COVID-19) epidemic, and discuss the differences in stress load and professional benefit of hemodialysis nurses between the two periods.MethodsIn February 2020, 119 hemodialysis nurses from three hemodialysis centers in Sichuan Province were selected as the respondents. Using the Stress Overload Scale and the Questionnaire of Nurses’ Perceived Professional Benefits, questionnaire survey was conducted in February 2020 and April 2020, respectively. Paired-sample t test was used for analysis.ResultsA total of 109 valid questionnaires were collected. The scores of stress load of hemodialysis nurses in outbreak period and remission stage were 3.00±1.26 and 2.17±1.16, respectively, of which the scores of event load dimension were 3.49±1.15 and 2.31±1.27, respectively, and the scores of individual vulnerability dimension were 2.59±1.19 and 2.05±1.06, respectively; the professional benefit scores of hemodialysis nurses in outbreak and remission were 4.19±0.83 and 4.21±0.78, respectively. The difference in stress load of the same group of hemodialysis nurses between different time periods was statistically significant (P<0.05), while there was no significant difference in professional benefit (P>0.05).ConclusionsDuring the outbreak of COVID-19 epidemic, the stress load of hemodialysis nurses was ata medium level, and that in the remission stage of COVID-19 epidemic was at a low level; the professional benefit of nurses in the outbreak and remission period was at a high level. The stress load status of hemodialysis nurses was different between different periods of the epidemic. We should take incentive mechanism or targeted psychological intervention measures to improve the professional benefit level of nurses.