ObjectiveTo introduce the progressing history of DO technique,and report the characteristics of the home-made type MS-1 internal mandibular distracter, and the effects of application of it in animal experiment. Methods15 Mongrel dogs were subjected to be lengthened of the unilateral or bilateral mandibles using the home-made type MS-1 mandibular distracter, and the regular X-ray ex aminations were made. ResultsAbout (20±5)mm in length of the andible had been achieved by the DO (distraction of osteogenesis)technique using the device. The accuracy of the distracter on lengthening would be attained to 98 % of the expectancy. The mineralization of the new bone fulfilled the gap zone about 5 weeks after the distraction had been finished during the consolidation period. ConclusionThe MS-1 type internal mandibular lengthening device has its special advantages on ap plication of cranio-maxillofacial surgery with a great expectancy.

Objective The method of bone lengthening by distraction of callus was used on dog mandible as a model to study the capability and changes of membranous bone during distraction osteogenesis. Methods 15 dogs aged 5～7 months were chosen as the subjects. The operation included a unilateral or bilateral periosteal preserving corti cotomy of mandibular bone, and an introral mini lengthening device were fixed to the buccal side of the mandible. After 7d, the mandible was lengthened lmm/d for 20d and then held in internal fixation for 7～ 140d (1 ～ 20 weeks). Results The dogs were killed at 3 times. Anthropometric measurements, X-ray examination and histological observa tion were conducted and conformed that the distracted bone had formed in the expanded zone successfully. Conclu sion The results suggested that we could use the DO technique in the area of craniofacial clinic. The strong ability of generating new bone in membranous skeleton by DO technique should be further demonstrated in the future.

Objective: To study the effect of palate repair operation on middle ear function. Methods: Cleft palate was repaired with double-opposing Z-plasty(DOZ) in 20 cases and with routin method (RM ) in 23 cases. Secretory otitismedia (SOM), high negative pressure (HNP), stapedial reflex(SR) and low acoustic compliance (LAC) were determined 3d before and 6 months after operation respectively. Results: Of the total 86 ears, before operation the persentages of SOM, HNP, SR and LAC were 61. 63, 75. 58, 29. 07 and 65. 15; after operation those were 31.39, 43.02, 66.28 and 33.72, respectively. Of the 40 ears of the cases treated with DOZ the persentages of those were 20.00, 27.50, 72.50 and 25.00) while of the 46 ears of the cases treated with RM those were 41.30, 56.52, 60.87 and 41.30 respectivellly. Conclusion: Middle ear function can be improved by palate repairs surgery, better results may be achieved with double opposing Z-plasty technique.

Objective To discuss the protection of parathyroid and application of nano-carbon suspen-sion in thyroid surgery .Methods 80 cases were randomly divided into 2 groups:the experimental group which were injected nano-carbon into thyroid during thyroidectomy , and the control group without any injection .Results There were 5 cases with hypocalcemia and 5 cases with PTH decrease in the experimental group , and there were 15 cases and 14 cases respectively in the control group .Pathological results showed that misresection of par-athyroids occurred in 6 cases of the control group(11 parathyroid glands)were while it didn't happen in the experi-mental group .Conclusion Nano-carbon can help to identify and protect the parathyroid , decreasing the proba-bility of parathyroid gland damage during thyroid surgery .

Objective:To explore the preoperative 68Ga-PSMA PET/CT examination on the guidance of surgical strategies for high-risk prostate cancer patients and the influence of positive surgical margins after surgery. Methods:The clinical data of 118 patients with high-risk prostate cancer who underwent robot-assisted laparoscopic radical prostatectomy from June 2019 to December 2020 in Xijing Hospital of Air Force Military Medical University was retrospectively analyzed. 47 patients received 68Ga-PSMA PET/CT examination before surgery (study group), and 71 cases without 68Ga-PSMA PET/CT examination before operation ( control group). There was no statistically significant difference in the age [69 (63, 76) vs. 67 (64, 74) years], PSA [PSA≤20ng/ml: 9.91 (6.00, 13.67) vs. 11.64 (8.15, 15.44) ng/ ml, PSA> 20ng/ml: 66.53 (53.66, 195.30) vs. 63.18 (30.08, 148.05) ng/ml], preoperative clinical staging (T 2/≥T 3: 21/26 cases vs. 34/37 cases), and Gleason score [8 (7, 9) vs. 8 (7, 9) points] (all P>0.05) between study group and control group. Both groups underwent robot-assisted laparoscopic radical prostatectomy. The surgical plan was based on the PSMA PET/CT and MRI results in study group and control group respectively. First, ensure that all tumors are removed, and secondly, preserve the patient's urethral length as much as possible to ensure postoperative urinary control.If there is seminal vesicle invasion, expand the scope of resection as needed. If lymph node metastasis is shown, lymph node dissection is performed. For those with negative lymph nodes in imaging studies, if enlarged lymph nodes are found during the operation, lymph node dissection is also performed. After the operation, the perioperative results and surgical margins of the two groups were compared, and the correlation between the PSA value and the SUVmax value of prostate cancer tissue was analyzed. Results:The operations of the two groups were successfully completed, and there was no transfer to open surgery. The operation time of the study group was shorter than that of the control group [175 (155, 205) min vs. 205 (155, 235) min, P=0.003], and the positive rate of resection margin was significantly lower than that of the control group [23.40% (11/47) vs. 45.07%(32/71), P=0.017]. For patients with pathological stage ≥pT 3, the positive rate of surgical margins in the study group was significantly lower than that in the control group [30.77%(8/26) vs. 62.16%(23/37), P=0.014]. In the study group, 11 cases of PSMA-PET showed positive lymph nodes before operation, 10 cases were pathologically positive after operation (90.91%). PSMA-PET showed negative lymph nodes in 1 case, which was pathologically positive after operation. In the control group, 26 cases underwent lymph node dissection, and 16 cases (61.54%) were pathologically positive after operation. The preoperative PSA value of 47 cases in the study group was positively correlated with the SUVmax value of prostate cancer tissue ( r=0.579, P<0.01). Conclusions:Preoperative 68Ga-PSMA PET/CT for high-risk prostate cancer patients can guide the surgeon to optimize the surgical plan, reduce the positive rate of resection margins, and effectively remove the metastatic lymph nodes, which will benefit the patients.

Objective:To investigate the risk factors for biochemical recurrence after radical prostatectomy.Methods:The clinical data of 558 radical prostatectomy patients admitted to the First Affiliated Hospital of Air Force Military Medical University from January 2010 to December 2020 were retrospectively analyzed. The average age was 67.9 (40-87) years old, and the average body mass index was 24.56 (15.12-35.94) kg/m 2. The average PSA was 41.07 ng/ml, including 48 cases<10 ng/ml, 98 cases 10-20 ng/ml, and 412 cases>20 ng/ml. There were 123, 214, 118, 89, and 14 cases with biopsy Gleason 6-10 score, respectively. The clinical stage : 90 cases in ≤T 2b, 273 cases in T 2c, and 195 cases in ≥T 3 . 558 cases underwent radical prostatectomy, including 528 robotic-assisted laparoscopic surgery, 25 laparoscopic surgery, and 5 open-surgery. The risk factors for postoperative biochemical recurrence were analyzed by Cox regression. Results:A total of 63 patients had postoperative pathological stage pT 2a, 32 patients had pT 2b, 241 patients had pT 2c, and 222 patients had ≥pT 3. A total of 210 cases developed biochemical recurrence after surgery, and the mean time to biochemical recurrence was 33.3 (3-127) months after the radical prostatectomy. The biochemical recurrence rates at 1, 3, and 5 years were 9.7% (54/558), 21.5% (120/558), and 31.7% (177/558), respectively. Among pT 2a and pT 2b patients, 7 (11.1%) and 4 (12.5%) cases developed biochemical recurrence, respectively. Among pT 2c stage patients, 145 (60.17%) cases had positive cut margins, treated with androgen-deprivation therapy (ADT) after surgery. 68 (28.21%) cases of pT 2c stage patients had biochemical recurrence at mean 36.1 (3-106)months after the radical prostatectomy. Among ≥pT 3 patients, 147 patients with positive margins, perineural invasion, seminal vesicle invasion and positive pelvic lymph nodes were treated with postoperative androgen deprivation therapy (ADT) + radiotherapy. 98 of 147 patients (66.67%) had biochemical recurrence, and the average time to biochemical recurrence was 30.6 (24-98) months.75 patients of ≥pT 3 without positive margins, perineural invasion, seminal vesicle invasion or positive pelvic lymph nodes, were treated with postoperative ADT. 33 of them (44%) had biochemical recurrence, and the average time to biochemical recurrence was 32.5 (21-106) months. 5-and 10-year survival rates of 210 patients with biochemical recurrence were 89.05% (187/210) and 78.09% (164/210) respectively, 5- and 10-year tumor-specific survival rates were 92.57% and 87.69%, respectively. 46 of 210 cases died, of which 31 (67.39%) died from prostate cancer, and 15 cases (32.61%) died from cardiovascular and cerebrovascular diseases. Multifactorial Cox regression analysis showed that patient's age ≥70 years, initial PSA > 20ng/ml, ≥pT 3 and Gleason score ≥7 were independent risk factors for biochemical recurrence. Conclusions:After radical prostatectomy, patients were treated according to their pathological stage and surgical margins. Patients with positive margins have a higher risk of biochemical recurrence. The independent risk factors for biochemical recurrence included age ≥70 years, initial PSA > 20ng/ml, ≥pT 3 and Gleason score ≥7.

Objectives:This study aimed to evaluate the effect of the strategies on COVID-19 outbreak control in Shenzhen, and to clarify the feasibility of these strategies in metropolitans that have high population density and strong mobility.Methods:The epidemic feature of COVID-19 was described by different phases and was used to observe the effectiveness of intervention. Hierarchical spot map was drawn to clarify the distribution and transmission risk of infection sources at different time points. The Susceptible-Exposed-Infectious-Asymptomatic-Recovered model was established to estimate case numbers without intervention and compare with the actual number of cases to determine the effect of intervention. The positive rate of the nucleic acid test was used to reflect the risk of human exposure. A survey on COVID-19 related knowledge, attitude and behaviors were used to estimate the abilities of personal protection and emergency response.Results:The epidemic of COVID-19 in Shenzhen experienced the rising, plateau and decline stage. The case number increased rapidly at the beginning, with short duration of peak period. Although the epidemic curve showed human-to-human transmission, the "trailing" was not obvious. From the spot map, during the intervention period, the source of infection was widely distributed. More cases and higher transmission risk were observed in areas with higher population density. After the effective intervention measures, both infection sources and the risk of transmission decreased. After compared with the estimated case numbers without intervention, actual number proved the COVID-19 control strategies were effective. The positive rate of nucleic acid test for high risk populations decreased and no new cases reported since February 16. Shenzhen citizens had high knowledge, attitude and behavior level, and high protection ability and emergency response.Conclusions:Although the response initiated by the health administration department played a key role at the early stage of the epidemic, it was not enough to contain the outbreak of COVID-19. The first-level emergency response initiated by provincial and municipal government was effective and ensured the start of work resumption after the Spring Festival. Metropolitans like Shenzhen can also achieve the goals of strategies and measures for containment and mitigation of COVID-19.

Non-small-cell lung cancer (NSCLC), the most common type of lung cancer accounting for 85% of the cases, is often diagnosed at advanced stages owing to the lack of efficient early diagnostic tools. 5-Hydroxymethylcytosine (5hmC) signatures in circulating cell-free DNA (cfDNA) that carries the cancer-specific epigenetic patterns may represent the valuable biomarkers for discriminating tumor and healthy individuals, and thus could be potentially useful for NSCLC diagnosis. Here, we employed a sensitive and reliable method to map genome-wide 5hmC in the cfDNA of Chinese NSCLC patients and detected a significant 5hmC gain in both the gene bodies and promoter regions in the blood samples from tumor patients compared with healthy controls. Specifically, we identified six potential biomarkers from 66 patients and 67 healthy controls (mean decrease accuracy >3.2, P < 3.68E-19) using machine-learning-based tumor classifiers with high accuracy. Thus, the unique signature of 5hmC in tumor patient's cfDNA identified in our study may provide valuable information in facilitating the development of new diagnostic and therapeutic modalities for NSCLC.
5-Methylcytosine ; analogs & derivatives ; blood ; Biomarkers, Tumor ; blood ; genetics ; Carcinoma, Non-Small-Cell Lung ; blood ; diagnosis ; genetics ; Case-Control Studies ; Circulating Tumor DNA ; blood ; DNA Methylation ; Epigenomics ; Female ; Humans ; Lung Neoplasms ; blood ; diagnosis ; genetics ; Male ; Middle Aged