OBJECTIVETo establish a miniature pig model of mandibular osteoradionecrosis (ORN).

METHODSA single dose of irradiation (IR25 Gy, 28 Gy) was delivered via an electronic linear accelerator to the right mandible of 24 miniature pigs by utilizing three dimensional conformal radiotherapy (3D-CRT). The first molar of the mandible was extracted 2 months after radiation. Mandibular ORN was diagnosed through gross observation, X-ray film, CT, and histopathologic examination.

RESULTSAt 3-4 months after radiation, all animals suffered from mandibular ORN after dental extraction. The symptoms of ORN were more severe in the 28 Gy group than in the 25 Gy group.

CONCLUSIONA miniature pig model of mandibular ORN can be established through 25 Gy irradiation + dental extraction.

Animals ; Mandible ; Mandibular Diseases ; pathology ; Molar ; Osteoradionecrosis ; pathology ; Particle Accelerators ; Radiation Injuries, Experimental ; pathology ; Radiotherapy, Conformal ; adverse effects ; Swine ; Swine, Miniature ; Tooth Extraction

Objective: To explore the application of the 3D precise digital technology in restoring structural defects of the orbital region. Methods: Structural defects of the orbital region concerning on osseous structure and soft tissue were restored in one stage or stages using EH composite artificial bone prosthesis with complex three-dimensional structure. The fabrication of EH composite artificial bone prosthesis was based on CT scanning and 3D reconstruction of the skull with computer aided data analysis and design. The appearance, degree of satisfaction and the complications were evaluated in postoperative regular follow-up. Results: Five cases of structural defects in the orbital regions presenting bone defect and soft tissue abnormality, received treatments in the department from January 2016 to September 2017. The cases consist of one patient with dysplasia following surgical treatment, three with post-traumatic and one with Treacher-Collins syndrome. With the application of individualized EH composite artificial bone fabricated by aforementioned method, all the repair materials presented the ideal three-dimensional structure and coincided well with the defects, and soft tissue restoration of 2 cases was performed in one stage or by stages. Appearance and symmetry of the 5 cases was significantly improved, without complications of infection, rejection, exposure or graft tissue necrosis. All the patients were satisfied with the results. Conclusions In consideration of the capacity to fabricate accurate individualized repair materials, the three-dimensional digital technology plays an important role in the treatment of structural defects in the orbital region, especially the reconstruction of the bony contour. The simple orbital deformities can be treated with the repair materials and correction of soft tissue. For special orbital deformities, attention should be paid to bone structure repair, eye socket reconstruction and filling of orbital contents sequentially.

Objective:To improve the awareness of primary myeloid sarcoma.Methods:The clinical data of one primary myeloid sarcoma patient with first symptom involving nasopharynx who was admitted to the Second Affiliated Hospital of Anhui Medical University in June 2017 were retrospectively analyzed, and the related literature was reviewed.Results:The patient presented with nasal congestion with tinnitus; it took half a year for the myeloid sarcoma diagnosis to be clear with biopsy and immunohistochemical examinations for many times. The patient was treated with chemotherapy regimens for acute myeloid leukemia (AML). Isolated myeloid sarcoma relapsed with skin masses after remission for more than 2 years. Further improvement of the bone marrow-related examinations showed that the bone marrow was not involved, and it was still isolated myeloid sarcoma. The skin mass disappeared completely after the induction chemotherapy of AML. Six months after the recurrence, the patient was in stable condition and was still under follow-up treatment.Conclusions:The primary nasopharyngeal myeloid sarcoma lacks specificity and is easy to be misdiagnosed. The prognosis of isolated myeloid sarcoma is better than that of AML. Isolated recurrence after chemotherapy remission is rare, and usually progresses to the leukemia stage quickly. Early and correct diagnosis is very important for the prognosis, and clinicians should improve the awareness of primary myeloid sarcoma.

Myopia has become a major health problem on global scale due to its increasing high prevalence in the past few decades and gradual younger onset age.Accumulated epidemiological surveys have shown that decreased time of exposure to sunlight would be an inducement for the development of myopia.Increasing time spent outdoors and exposure to sunlight might be the most cost-effective and effective measure for children to prevent myopia.This paper summarizes the progress in research of the association between sunlight exposure and myopia in children and its mechanisms to provide new clues for the research on myopia prevention and control.

Objective: The aim of this study was to describe the distribution of neck-shoulder symptoms among middle school students, and to explore its influence factors. Methods: A cross-sectional survey was conducted on 24 middle schools in Shenyang, Zhengzhou and Shenzhen by purposive sampling method. In each middle school, 3 to 4 classes were selected from each grade all the students in the selected class would be recruited to the survey to investigate the demographic characteristics, neck-shoulder symptoms, physical exercise time, academic stress, screen behavior, sedentary behavior and other information by questionnaire. A total of 10 566 questionnaires were issued and 10 270 valid questionnaires were withdrawn. The prevalence of neck-shoulder symptoms among students were compared by different characteristics. Logistic regression models were applied to examine influencing factors associated with neck-shoulder symptoms. Results: The prevalence of neck-shoulder symptoms among middle school students was 19.2% (1 968/10 270), while it was 22.6% (1 137/5 039) among girls and 15.9% (831/5 231) among boys; the difference showed statistical significance (P<0.001). The prevalence of neck-shoulder symptoms was separately 13.3% (253/1 901) in seventh grade, 16.8% (326/1 942) in eighth grade, 18.5% (299/1 617) in ninth grade, 21.8% (417/1 915) in sophomore, 21.4% (345/1 611) in junior, 25.5% (328/1 284) in senior; the difference showed statistical significance (P<0.001). The multivariate logistic regression analysis showed that in the last 3 months, students who always playing mobile phone ≥40 min continuously (OR=4.66, 95%CI: 3.95-5.49), watching TV ≥40 min continuously (OR=4.01, 95%CI: 3.39-4.73), using computer ≥40 min continuously (OR=3.61, 95%CI: 3.09-4.23), doing homework ≥60 min continuously (OR=3.25, 95%CI: 2.79-3.79), the average daily sitting time ≥10 h (OR=4.95, 95%CI: 4.25-5.77), and always sitting ≥90 min continuously (OR=5.18, 95%CI: 4.42-6.06) were risk factors of neck-shoulder symptoms. Conclusion The prevalence of neck-shoulder symptoms was high among middle school students in China, especially girls in senior grades. Long time, high frequency video behaviors and sedentary behaviors were related to the occurrence of neck-shoulder symptoms among middle school students.

Objective: To examine the relationship between the prevalence of self-reported myopia and outdoor activities among middle school students and to explore the influence factors of the self-reported myopia. Methods: A total of 12 979 participants were recruited from junior and senior middle school students in in Shenzhen, Nanchang, Zhengzhou and Shenyang by random cluster sampling method between December 2015 and March 2016. All participants completed an anonymous questionnaire to collect the information of demographic characteristics, self-reported myopia, outdoor activities, etc. 12 603 out of 12 979 copies of questionnaire were valid. The prevalence of self-reported myopia was compared among middle school students with different characteristics. Logistic regression models were used to analyze the relationship between myopia and outdoor activities. Results: The prevalence of self-reported myopia among middle school students was 69.6% (8 766/12 603); which was separately 52.1% (1 216/2 335) in seventh grader, 61.6% (1 459/2 369) in eighth grader, 69.0%(1 470/2 129) in ninth grader, 80.0% (1 812/2 265) in freshmen, 79.4% (1 622/2 042) in sophomore, and 81.1%(1 187/1 463) in junior. The prevalence of self-reported myopia showed an increasing trend with the increase of grade (χ²=639.67, P<0.001). The prevalence of self-reported myopia was separately 63.5%(4 927/7 756) in non-myopic parents group, 78.0%(2 664/3 415)in either myopic parent group, and 82.1%(1 175/1 432) in both myopic parents group(χ²=328.28, P<0.001). Outdoor activities were associated with self-reported myopia. Binary logistic regression analysis showed that the risk of self-reported myopia was significantly increased by always staying at home in extracurricular time among the middle school students (OR=1.58, 95%CI: 1.36-1.82). The risk of self-reported myopia were significantly decreased by always physical exercise and recreational activities after school among middle school students: the ORs were separately 0.67 (95%CI: 0.57-0.78) for physical exercise and 0.77 (95%CI: 0.64-0.92) for recreational activities. After stratified analysis by the parents' myopia status, in non-myopic parents group, exercise and recreational activities after school among middle school students decreased the risk of myopia: the ORs were separately 0.68 (95%CI: 0.55-0.82) for physical exercise and 0.76 (95%CI: 0.61-0.95) for recreational activities; in either myopic parent group, OR(95%CI) were separately 0.65 (0.47-0.90) and 0.68 (0.47-0.98). Conclusion Outdoor activities was negatively associated with self-reported myopia among middle school students. However, the parents' myopia status may affect the protective effect.

Objective : To investigate the 90 day prognosis of acute ischemic stroke patients treated with mechanical thrombectomy in the real world and analyze the related factors of prognosis． Methods: A total of 1 033 acute ischemic stroke patients treated with mechanical thrombectomy in tertiary hospitals of Anhui province were retrospectively investigated．The 90 day modified Rankin Scale (mRS) score was evaluated by follow-up telephone，0 ～2 points were good prognosis and 3 ～6 points were poor prognosis. Results : A total of 770 patients were followed up，with an average age of (67. 7 ± 11. 8) years．The good prognosis rate was 32. 1% and the mortality rate was 31. 8% . With the increase of age，the good prognosis rate showed a downward trend while the mortality rate showed an upward trend．The best cut-off value for age prediction of 90-day mortality was 69 years old．There was no gender difference in the good prognosis rate between women (70. 6 ± 10. 6) years and men (65. 6 ± 12. 2) years，but females experienced a higher mortality than males (37. 1% vs 27. 9% ) before adjusting for age． Comparison was made among provincial，municipal and county hospitals，only the good prognosis rate of provincial hospitals was significantly higher than that of county hospitals (37．2% vs 15. 6% ) ．In the grouping of annual number of endovascular treatment cases，the good prognosis rate of only ≥40 cases group was significantly higher．There was no significant difference in mortality among the groups． Conclusion At present，the good prognosis is low and the mortality is high for the whole acute ischemic stroke patients treated with mechanical thrombectomy．Age was positively correlated with poor prognosis and mortality．The higher mortality rate in women than in men is due to the higher average age of onset in women．The good prognosis rate of provincial hospitals and hospitals with annual number of endovascular treatment ≥40 cases is higher than that of other hospitals.

OBJECTIVETo investigate the treatment effect of mandibular osteoradionecrosis (ORN) by autologous bone marrow mesenchymal stem cells (BMMSC) in miniature pigs.

METHODSSix miniature pigs with mandibular ORN (25 Gy) were used. BMMSC were separated and cultured in vitro and then implanted on to the premolded hydroxyapatite-tricalcium phosphate (HA-TCP). The BMMSC-HA-TCP complexes were implanted into the defective area of mandibular ORN in 4 animals. Implantation of only HA-TCP in 2 animals served as control. Gross observation, spiral CT, coronary CT and histopathologic examination were carried out.

RESULTSFistula disappeared in animals with BMMSC-HA-TCP complexes 3 months after implantation, while fistula was found in controls. Spiral CT analysis showed that cortical bone repair were found 4 months after BMMSC-HA-TCP complexes implantation, while bone damage (cortical and cancellous bone fracture) increased in controls. Histopathologic examination revealed that 4 months later after BMMSC-HA-TCP complexes implantation, new bone formation and bone cells could be observed, but there was a large number of fibrous tissue and no new bone in controls.

CONCLUSIONSTransplantation of autologous BMMSC with HA-TCP may have therapeutic effect in the treatment of mandibular ORN.

Animals ; Bone Marrow Cells ; Calcium Phosphates ; therapeutic use ; Durapatite ; therapeutic use ; Mandibular Diseases ; therapy ; Mesenchymal Stem Cell Transplantation ; Osteoradionecrosis ; therapy ; Swine ; Swine, Miniature ; Transplantation, Autologous