[Analysis of highly cited papers in Chinese Journal of Epidemiology from 2020 to 2023].

Objective: To analyze the characteristics of highly-cited papers in Chinese Journal of Epidemiology from 2020 to 2023, and provide a basis for subsequent paper solicitation and identify research hotspots. Methods: On December 9, 2023, the citation frequency of each paper in Chinese Journal of Epidemiology from 2020 to 2023 was obtained from China National Knowledge Infrastructure. The total citation frequency of each paper was sorted using Excel 2016 software, and papers with citation frequency ≥30 were extracted for analysis. The keywords of the papers and Contents in Brief were analyzed. Results: A total of 1 317 papers were included in the analysis, of which 389, 342, 308 and 278 papers were included from 2020 to 2023. The total citation frequency was 11 873, and all papers were cited with an average citation frequency of 9. The keywords with high citation frequency in the papers included 2019-nCoV, hypertension, colorectal tumor, hand-foot-mouth disease, hepatitis B. and the average frequency of citation were 162, 77, 62, 51 and 47, respectively. There were 15 highly cited Contents in Brief in total, 11 of which are vital Contents in Brief or unique Contents in Brief, including Response to COVID-19 Epidemic, China Kadoorie Biobank, Epidemiological Research on Infectious Diseases, Healthy Ageing, Colorectal Cancer Prevention and Control, Prevention and Control of Hepatitis B, Quality Assessment of Cancer Screening Guidelines and Consensus, The 40th Anniversary of Chinese Journal of Epidemiology, Expert Forum, Review, Standard-Protocol-Guide. The total citation frequency was 3 951, accounting for 72.6% (3 951/5 438) of highly cited papers. Conclusions: In the past four years, the highly cited papers of this journal mainly focused on the research field of emerging infectious diseases and chronic diseases. The response to the 2019-nCoV epidemic highlights the academic leading role. The effect of selecting and planning a topic, commissioning authors to write on given topics and making an arrangement in advance with a subject for contribution to vital Contents in Brief or unique Contents in Brief of this journal is pronounced, and the academic influence of the journal continues to improve.

[A retrospective cohort study of case fatality rate of HIV/AIDS cases and influencing factors in Jingzhou, Hubei Province, 1996-2021].

Objective: To analyze the case fatality rate of HIV/AIDS cases and influencing factors in Jingzhou. Methods: The data were retrieved from HIV/AIDS Comprehensive Response Information System and the cases diagnosed with HIV/AIDS in Jingzhou during 1996-2021 and aged 15 years or older were selected for the study. The death curve was drawn with Kaplan-Meier method, and Cox proportional-hazards model was used to identify influencing factors for death. Results: A total of 3 304 HIV/AIDS cases were followed up for 16 091.5 person-years, and 893 cases died, with a case fatality rate of 5.5/100 person-years. The cumulative case fatality rates of 1, 5 and 10 years were 15.4%, 25.0% and 34.6% respectively, the cumulative case fatality rates of 1, 5 and 10 years were 6.9%, 14.4% and 23.7% in the cases with access to antiretroviral therapy (ART), and 68.0%, 90.1% and 98.7% in the cases without access to ART. The results of Cox proportional hazards regression model showed that the risk for death was higher in those without access to ART than in those with access to ART (aHR=9.85, 95%CI: 8.19-11.85). The risk factors for death in those with access to ART included being men (aHR=1.64, 95%CI: 1.29-2.08), age ≥60 years old at diagnosis (aHR=3.52, 95%CI: 2.38-5.20), being infected by injecting drug use/others (aHR=2.38, 95%CI:1.30-4.34), being detected by medical institution (aHR=1.53, 95%CI: 1.11-2.11), CD4+T lymphocytes(CD4) counts <50 cells/µl (aHR=2.58, 95%CI: 1.87-3.58). The protective factor for death was high education level (high school and technical secondary school: aHR=0.64,95%CI:0.46-0.90; college and above: aHR=0.42, 95%CI: 0.24-0.73). The risk factors for HIV/AIDS death in those without access to ART included older age at diagnosis (30-44 years old: aHR=2.32, 95%CI: 1.40-3.84; 45-59 years old:aHR=2.61, 95%CI: 1.59-4.27; ≥60 years old: aHR=3.31, 95%CI: 2.01-5.47), lower CD4 counts (<50 cells/µl: aHR=10.47, 95%CI: 6.47-16.56; 50-199 cells/µl: aHR=2.31, 95%CI: 1.08-4.94; 200-349 cells/µl: aHR=2.35, 95%CI: 1.46-3.79). Conclusions: The case fatality rate of HIV/AIDS was relatively high in Jingzhou from 1996 to 2021, the first CD4 counts, ART and age at diagnosis were the major factors affecting HIV/AIDS death, "Expanding testing" and "prompt treatment upon diagnosis" should be continued and enhanced to improve the efficacy of ART and HIV/AIDS case survival.

[Dysphagia and respiratory rehabilitation in patients with Post-ICU Syndrome].

Post-ICU Syndrome (PICS) is a complex disease with multiple aspects, including physical, cognitive, and psychological health problems. Dysphagia persists in patients with PICS and is independently associated with adverse clinical outcomes after discharge. With the development of the level of intensive care, dysphagia of PICS needs more attention. Although several risk factors related to dysphagia in PICS have been proposed, the exact mechanism is still unclear. Respiratory rehabilitation is an important non-pharmacological therapy, which offers short-and long-term rehabilitation in critical patients, but its application is insufficient in dysphagia of PICS. In view of the lack of consensus on the rehabilitation treatment of dysphagia after PICS currently, the article elaborates on the related concepts, epidemiology, potential mechanisms and the application of respiratory rehabilitation in patients with dysphagia of PICS, in order to provide a reference for the clinical development of respiratory rehabilitation in patients with dysphagia of PICS.

[Analysis on academic quality and influence of Chinese Journal of Epidemiology, 2006-2019].

Objective: In recent years, the editorial board and editorial department of Chinese Journal of Epidemiology have taken a series of measures to further improve the academic quality and influence of the journal. This study analyzed the citation index of Chinese Journal of Epidemiology from 2006 to 2019, and evaluated the academic quality and influence of the journal. Methods: The total citation frequency, impact factor, annual index and other citation rate etc. of Chinese Journal of Epidemiology were extracted from Chinese S&T Journal Citation Report, 2006-2019 (Expanded Edition) and Chinese S&T Journal Citation Report, 2006-2019 (Natural Science) for the analysis on academic quality and influence of the journal. Results: From 2006 to 2019, there were 241-406 articles published in Chinese Journal of Epidemiology per year. The literature selection rate over the years ranged from 66% to 100%. The total expanded citation frequency of Chinese Journal of Epidemiology increased from 3 365 in 2006 to 7 817 in 2019, and the total core citation frequency increased from 1 875 in 2006 to 5 055 in 2019 with slight fluctuation. The expanded impact factor increased from 1.566 in 2006 to 2.799 in 2019. The core impact factor increased from 0.904 in 2006 to 1.842 in 2019. The expanded annual index rose from 0.224 in 2006 to 0.741 in 2019. The core annual index rose from 0.170 in 2006 to 0.602 in 2019. Conclusion: The academic quality and influence of Chinese Journal of Epidemiology has been improved gradually and its ability to focus on hot spots and report new academic achievement has been further strengthened in recent years.

[Value of serum parathyroid hormone in the diagnosis of primary aldosteronism].

Objective: To explore the value of serum parathyroid hormone (PTH) in the diagnosis of primary aldosteronism (PA) and to investigate an optimal cut-off of serum PTH to distinguish PA from nonfunctional adrenal tumor (NFA). Methods: The clinical data of patients with adrenal incidentaloma in Chinese PLA General Hospital from January 1, 2017 to December 31, 2019 were collected. The data of PA and NFA by clinical characteristics and evaluation on endocrine function were retrospectively analyzed. The logistic regression model was used to find the potential risk factors of elevated PTH. The receiver operating characteristic(ROC) curve was used to evaluate the efficacy of PTH in diagnosis of PA and to explore the best cut-off value. Results: A total of 773 patients were included. There were 356 PA patients (203 males, 57.0%), aged (50±11) years and 417 NFA patients (219 males, 52.5%), aged (51±12) years. The serum PTH level in patients with PA was significantly higher than that in patients with NFA [63.1 (48.4, 80.3) ng/L vs 41.7 (34.1, 51.7) ng/L, P<0.05], as well as the proportion of patients with elevated PTH level (47.8% vs 7.2%, P<0.05). Logistic regression analysis showed that having PA and deficiency of Vitamin D were risk factors for PTH elevation (both P<0.05). The ROC curve showed that the best cut-off value of PTH for the diagnosis of PA in patients with vitamin D deficiency was 56.44 ng/L, with a sensitivity of 66.5% and a specificity of 83.0%, and that in patients with normal vitamin D was 48.81 ng/L, with a sensitivity of 70.5% and a specificity of 72.6%. Conclusions: Patients with PA tend to show increased levels of serum PTH compared with NFA patients. The level of serum PTH can be used as one of the valuable indexes in screening of PA.

[Characteristics and recovery of hearing loss in 573 patients with bacterial meningitis].

Objective: To analyze the characteristics and prognosis of hearing loss in children with bacterial meningitis. Methods: This was a single-center retrospective cohort study. Patients diagnosed with bacterial meningitis who were hospitalized in Beijing Children's Hospital between 2010 and 2016 and older than 28 days and younger than 18 years at symptom onset were included in this study (n=573). All clinical information including hearing assessment results during hospitalization were reviewed. All patients with hearing loss were followed up to repeat their hearing test and assess their hearing condition with parents' evaluation of aural and (or) oral performance of children (PEACH). Patients were grouped according to their hearing assessment results, and Logistic regression analysis was used to analyze the risk factors for hearing loss in patients with bacterial meningitis. Results: Five hundred and seventy-three patients were enrolled in this study, including 347 males and 226 females. The onset age ranged from 29 days to 15.8 years. Two hundred and forty-six patients had identified causative pathogens, among whom 92 cases (37.4%) were pneumococcal meningitis cases. Hearing loss was found in 160 cases (27.9%) during hospitalization, involving 240 ears. Permanent hearing loss was found in 20 cases (16.9%), involving 32 ears. In the patients with permanent hearing loss, 87.5% (28/32) of ears were identified as severe or profound hearing loss during hospitalization. Logistic regression analysis showed that dystonia, the protein concentration level in cerebrospinal fluid>1 g/L, glucose concentration level lower than 1 mmol/L and subdural effusion were independent risk factors for hearing loss (OR=2.426 (1.450-4.059), 1.865 (1.186-2.932), 1.544 (1.002-2.381) and 1.904 (1.291-2.809)). Conclusions: Hearing loss is a common sequela of bacterial meningitis in children. Most patients have transient hearing loss, but patients with severe or profound hearing impairment have a higher risk of developing permanent hearing loss.

[Systematic review of the epidemiological characteristics of inhalation injury in burn patients in China].

Objective: To study the epidemiological characteristics of inhalation injury in burn patients in China. Methods: The systematic review method was performed. Chinese Journal Full-text Database, Wanfang Database, and Chinese Biomedical Literature Database were searched with the Chinese search terms of ", , ", and PubMed and Embase were searched with the search terms of "burns, inhalation injury" to retrieve the collected retrospective studies on the epidemiological characteristics of inhalation injury in burn patients in China from the establishment of each database to January 2019. Data were extracted from the included articles, including the first author, study institution, study period, study subjects, number of burn patients, incidence of inhalation injury, and gender, age, causes of injury, mortality, and causes of death in patients with inhalation injury. Results: A total of 24 articles were included in this study with the first authors being from multiple research institutions across the country. The articles reported single or multi-center epidemiological studies with statistics on the incidence of inhalation injury in burn patients or severe burn patients admitted to key burn treatment institutions in many provinces/cities in China from 1958 to 2016. The number of burn patients included was 103-64 320 cases in the studies, and the incidence of inhalation injury in hospitalized burn patients ranged from 4.89% to 11.28%, with no obvious trend. The incidence of inhalation injury in severe burn patients was still high, from 19.09% to 32.38% as most articles reported. The number of men with inhalation injury was larger than that of women, with a male-to-female ratio of 1.61 ∶1.00-4.95 ∶1.00; young and middle-aged people were the high-risk population, and flame burn was the main cause of injury. The mortality of patients with inhalation injury was 5.17%-58.67%, of which the mortality was 5.17%-24.75% since 2000, in accordance with reports from hospitals in various regions that the mortality in the later period decreased significantly compared with the previous period. The causes of death in patients with inhalation injury included upper respiratory tract obstruction, sepsis, respiratory failure, and severe pulmonary infection. Conclusions: From 1958 to 2016, there is no obvious trend in the incidence of inhalation injury among burn patients in China; the incidence of inhalation injury is high in young and middle-aged males, and the main cause of inhalation injury is flame burn. The mortality of inhalation injury generally decreased since 2000 compared with the previous period.

[Preliminary analysis of intestinal microflora in patients with different severity of OSAHS].

Objective: To analyze the diversity, abundance and structural composition of intestinal microflora in patients with different severity of OSAHS, and to explore their potential role in the occurrence and development of OSAHS. Methods: A total of 27 healthy volunteers(N) [male 19, female 8, age 22-78(44.4±2.7)years old] of Health Examination Center of the Second Hospital of Shanxi Medical University and 100 patients with OSAHS [male 86, female 14, age 19-78(49.1±1.3) years old] of Sleep Medicine Center of the Second Hospital of Shanxi Medical University were enrolled from December 2018 to September 2019, and patient-related sleep monitoring data and medical history data were collected.According to the AHI classification and whether there were complications, OSAHS patients were divided into mild group (L), moderate group (M), severe group (S) and severe complication group (SC).Using 16S rRNA high-throughput sequencing technology to analyze the intestinal flora of all people, bioinformatics related statistics were analyzed by QIIME2 software, and clinical data were analyzed by SPSS 25.0 software. Results: There was no significant difference in intestinal flora Alpha and Beta diversity among all groups (P>0.05). At phylum level, the relative abundance of Bacteroides in OSAHS group was lower than that in normal group (N group: 24.96%, L group: 18.31%, M group: 12.95%, S group: 15.78%, Sc group: 16.48%). At genus level, the relative abundance of Bacteroides (N group:16.03%, L group: 10.82%, M group: 9.79%, S group: 9.29%, Sc group: 8.25%) and Faecalibacterium (N group: 11.21%, L group: 10.42%, M group: 10.21%, S group: 8.54%, Sc group: 6.27%) were negatively correlated with the severity of OSAHS (the values of r respectively were -0.887, -0.945) while the relative abundance of Bifidobacterium (N group: 3.20%, L group: 2.47%, M group: 4.10%, S group: 4.93%, Sc group: 6.27%) and Blautia (N group: 2.52%, L group: 3.59%, M group: 3.81%, S group: 4.11%, Sc group: 5.86%) were positively correlated with the severity of OSAHS (the values of r respectively were 0.916, 0.940) Compared with the S group, the relative abundance of Roseburia (S group: 10.22%, Sc group: 6.65%) in the Sc is lower and the relative abundance of Shigella(S group: 4.64%, Sc group: 10.01%) is higher. Redundancy analysis (RDA) showed that Apnea hypopnea index (AHI), The lowest oxygen saturation (SpO2min), The average saturation of blood oxygen (SpO2mean) and The longest time of apnea (Tmax) were not significantly correlated with the overall abundance of intestinal flora (P>0.05), However, there was a significant correlation between the abundance of different flora and sleep monitoring indicators. Conclusion: There is an intestinal microecological imbalance in patients with OSAHS, mainly due to the reduction of the relative abundance of probiotics producing short-chain fatty acids and the increase of pathogenic bacteria, suggesting that the disturbance of intestinal flora may be related to the occurrence and development of OSAHS.

[Observation of cosmetic effect of corneal interlamellar staining in patients with corneal leucoma].

Objective: To observe the clinical effect of corneal staining in patients with corneal leucoma. Methods: Restrospective case series study.Thirty eyes of 30 patients (17 males, 13 females) with corneal leucoma who underwent corneal interlamellar staining at Beijing Aier-Intech Eye Hospital from October 2014 to July 2018 were included. The mean age was 31.50±15.66 years. Postoperative follow-up was more than 1 year. All the patients underwent appearance examination, anterior segment examination with a slit lamp, B-scan examination and anterior segment OCT examination preoperatively and postoperatively. The effect of corneal staining, patient satisfaction and the incidence of complications were investigated. Results: The corneal epithelium of all the patients healed completely within 1-3 days after operation. The mean follow-up period was 30.68±18.02 months (range, 12.37-58.10 months). During the postoperative follow-up period, no staining permeation or inflammatory reaction in the anterior chamber occurred. The corneal color and appearance were well maintained in 18 patients (72.0%). Seven patients (28.0%) showed mild corneal color-fading. One patient was treated with enucleation and orbital hydroxyapatite implantation because of eye atrophy and corneal banding degeneration caused by the primary disease at 4 years after operation. The surgeon was satisfied with the improvement of the appearance of all cases; 22 patients (88.0%) were satisfied with the postoperative appearance. No significant complications were observed in all the cases. Conclusions: Corneal interlamellar staining is one of best choices for the treatment of corneal leucoma. It has advantages of quick postoperative recovery, long-standing color staining and good cosmetic effect. The operation is simple and easy to carry out and there is no obvious damage to eye tissues. (Chin J Ophthalmol, 2020, 56:465-472).

Down-regulation of hsa_circ_0092125 is related to the occurrence and development of oral squamous cell carcinoma.

Circular RNA plays an important role in regulating tumour development and progression and can serve as a biomarker for cancer. This study was performed to investigate the clinical significance of hsa_circ_0092125 expression in oral squamous cell carcinoma (OSCC). The expression of hsa_circ_0092125 in OSCC tissues and cell lines was determined by reverse transcription-quantitative PCR analysis. The association between hsa_circ_0092125 expression and clinicopathological data was determined by χ2 test. Overall survival (OS) curves were created using Kaplan-Meier survival analysis, and the differences were examined by log-rank test. Moreover, univariate and multivariate Cox analysis were employed to evaluate the risk factors of the OSCC prognosis. The expression of hsa_circ_0092125 was significantly down-regulated in OSCC tissues and cell lines. A low expression of hsa_circ_0092125 was associated with clinicopathological factors in OSCC patients, including tumour size, TNM stage, and lymph node metastasis. Kaplan-Meier survival analysis indicated that the OS time was shorter in OSCC patients with a lower hsa_circ_0092125 expression level than in those with a higher expression level. In addition, univariate and multivariate Cox analysis identified lower hsa_circ_0092125 expression, tumour size, TNM stage, and lymph node metastasis as independent risk factors for the OSCC prognosis. Thus, down-regulated expression of hsa_circ_0092125 might serve as a biomarker of the OSCC prognosis.

Comparison of endoscope-assisted versus conventional resection of parotid tumors.

Endoscopically-assisted partial parotidectomy for benign tumours has been reported, but we have evaluated its feasibility through different concealed incisions compared with conventional parotidectomy. A total of 124 patients with parotid tumours were enrolled in this retrospective study: an endoscopically-assisted group (n=37) compared with a group operated on conventionally (n=87). The incision for endoscopically-assisted partial, total parotidectomy and selective neck dissection was based on location and pathological characters of the parotid tumour. The sex and age of the patients, diameter of the tumour, and histopathological features were comparable between the two groups. The mean length of the incision in the endoscopic group was significantly shorter than that in the conventional group. However, intraoperative blood loss, operating time, and duration of hospital stay were significantly reduced, and postoperative secretion of saliva was significantly improved in the endoscopic group, among whom there were no recurrences of tumour. More importantly, all patients who had endoscopically-assisted operations were satisfied with the cosmetic result. Endoscopically-assisted parotidectomy is superior to conventional resection as judged by postoperative cosmetic and functional outcomes. It is noteworthy that the site of incision depends mainly on location, and on the suspected low grade of malignancy of the parotid tumour seen on preoperative computed tomography and magnetic resonance images.

[Functional and supraomohyoid neck dissection in stage cN0/N1 oral squamous cell carcinoma].

Objective: To evaluate the clinical effects of functional neck dissection (FND) and supraomohyoid neck dissection (SOND) in patients with cN0/N1 oral squamous cell carcinoma (OSCC). Methods: A total of 210 patients with stage cN0/N1 OSCC underwent FND and SOND between January 2012 and May 2015 were retrospectively reviewed, among which, 147 patients were male and 63 were female, with an age range of 23-82 years and mean age of (62.2±10.2) years. There were 112 and 98 patients in FND and SOND groups, respectively. The follow-up data included cervical lymph node metastasis, movement of shoulder joint, great auricular nerve function, recurrence rate of cervical lymph nodes. Results: There was no significant difference in gender, age, tumor location, T stage, N stage, histological grades between the two groups (all P>0.05). Compared to patients in FND group, the activities of shoulder joint and earlobe numbness improved significantly in SOND group. Of the 210 patients, 17 patients (8.1%) had cervical recurrence, with 9 patients (8.0%) in FND group and 8 patients (8.2%) in SOND group. No significant difference was observed for neck recurrence between the two groups (P=0.973). Conclusion: SOND can be safely performed in cN0 or cN1 OSCC patients, which avoids major complications of FND, and improves postoperative quality of life in those patients.

[Current status of national free antiretroviral therapy in interprovincial migrating people living with HIV/AIDS and influencing factors, China, 2011-2015].

Objective: To understand the current status of national free antiretroviral therapy in interprovincial migrating people living with HIV/AIDS (PLWHA) and influencing factors in China. Methods: Descriptive and trend test analyses were performed to evaluate the historical characteristics and trends of main descriptive indicators on national free antiretroviral therapy for the interprovincial migrating PLWHA by using the data collected from National Comprehensive HIV/AIDS Information System from 2011 to 2015. Logistic regression model was used to explore the main factors that influencing the coverage of national free antiretroviral therapy among the interprovincial migrating PLWHA in China. Results: The proportion of interprovincial migrating PLWHA gradually increased in last 5 years from 7.1% (17 784/250 645) in 2011 to 10.3% (54 596/528 226) in 2015 (Z=51.38, P<0.000 1) in China. The coverage rate of free antiretroviral therapy in interprovincial migrating PLWHA increased from 37.3% (6 641/17 784) in 2011 to 71.0% (38 783/54 596) in 2015, showing a significant rising tendency (Z=96.23, P<0.000 1), but it was slightly lower than that in non-interprovincial migrating PLWHA in 2015 (71.5%, 338 654/473 630). Multivariate logistic regression analysis showed that the PLWHA who were females, aged ≥50 years, of Han ethnic group, married or had spouse, had the educational level of high school or above, infected through homosexual intercourse, with CD(4)(+)T cells counts ≤500 cells/µl at the first visit, identified to be infected with HIV in medical setting, living in urban areas et al, were more likely to receive free antiretroviral therapy. Conclusions: The coverage rate of free antiretroviral therapy varied among the interprovincial migrating PLWHA with different characteristics. It is still necessary to take effective measures to further increase the coverage of free antiretroviral therapy in interprovincial migrating PLWHA and to include the free antiretroviral therapy in interprovincial migrating PLWHA into standardized management system as soon as possible.

[Research progress on the role of NLRP3 inflammasome in ocular diseases].

Nucleotide-binding oligomerization domain-like receptor pyrin domain containing-3 (NLRP3) inflammasome is a type of multi-protein complex within the cell, the activation of which promotes the release of bioactive interleukin(IL)-1ß and IL-18 and contributes to inflammatory progress. In recent years, the research on the role of NLRP3 inflammasome in the pathogenesis and development of ocular surface and fundus diseases has made considerable progress. This review summarizes current understanding in the structure, ocular expression, and mechanisms of activation of NLRP3 inflammasome, as well as the contribution of this protein complex to eye diseases, thereby revealing the theoretical possibility that NLRP3 inflammasome might serve as a novel therapeutic target for the related ocular diseases.(Chin J Ophthalmol, 2018, 54: 396-400).

Virtual Planning and 3D printing modeling for mandibular reconstruction with fibula free flap.

BACKGROUND: This study was to evaluate the use of virtual planning and 3D printing modeling in mandibular reconstruction and compare the operation time and surgical outcome of this technique with conventional method. MATERIAL AND METHODS: Between 2014 and 2017, 15 patients underwent vascularized fibula flap mandibular reconstruction using virtual planning and 3D printing modeling. Titanium plates were pre-bent using the models and cutting guides were used for osteotomies. 15 patients who underwent mandibular reconstruction using fibula flap without aid of virtual planning and 3D printing models were selected as control group. The operation time was recorded and compared in two groups. Accuracy of reconstruction was measured by superimposing the preoperative image onto the postoperative image of mandible. The selected bony landmark, distance and angle were measured. RESULTS: The mean total operation time and reconstruction time were 1.60±0.37 and 5.54±0.50 hours in computer-assisted group, respectively; These were 2.58±0.45 and 6.54±0.70 hours in conventional group, respectively. Both operation time and reconstruction time were shorter in computer-assisted group. The difference between the preoperative and postoperative intercondylar distances, intergonial angle distances, anteroposterior distances and gonial angles were 2.92±1.15 and 4.48±1.41mm, 2.93±1.19 and 4.79±1.48mm, 4.31±1.24 and 5.61±1.41mm, 3.85±1.68° and 5.88±2.12° in the computer-assisted and conventional group, respectively. The differences between the preoperative and postoperative mandible is smaller in the computer-assisted group. CONCLUSIONS: Virtual planning and 3D printing modeling have the potential to increase mandibular reconstruction accuracy and reduce operation time. we believe that this technology for mandibular reconstruction in selected patients will become a used method and improve the quality of reconstruction.

[Data distribution and transformation in population based sampling survey of viral load in HIV positive men who have sex with men in China].

Objective: To understand the distribution of population viral load (PVL) data in HIV infected men who have sex with men (MSM), fit distribution function and explore the appropriate estimating parameter of PVL. Methods: The detection limit of viral load (VL) was ≤ 50 copies/ml. Box-Cox transformation and normal distribution tests were used to describe the general distribution characteristics of the original and transformed data of PVL, then the stable distribution function was fitted with test of goodness of fit. Results: The original PVL data fitted a skewed distribution with the variation coefficient of 622.24%, and had a multimodal distribution after Box-Cox transformation with optimal parameter (λ) of-0.11. The distribution of PVL data over the detection limit was skewed and heavy tailed when transformed by Box-Cox with optimal λ=0. By fitting the distribution function of the transformed data over the detection limit, it matched the stable distribution (SD) function (α=1.70, ß=-1.00, γ=0.78, δ=4.03). Conclusions: The original PVL data had some censored data below the detection limit, and the data over the detection limit had abnormal distribution with large degree of variation. When proportion of the censored data was large, it was inappropriate to use half-value of detection limit to replace the censored ones. The log-transformed data over the detection limit fitted the SD. The median (M) and inter-quartile ranger (IQR) of log-transformed data can be used to describe the centralized tendency and dispersion tendency of the data over the detection limit.

[Comparison of different methods in dealing with HIV viral load data with diversified missing value mechanism on HIV positive MSM].

Objective: To compare results of different methods: in organizing HIV viral load (VL) data with missing values mechanism. Methods We used software SPSS 17.0 to simulate complete and missing data with different missing value mechanism from HIV viral loading data collected from MSM in 16 cities in China in 2013. Maximum Likelihood Methods Using the Expectation and Maximization Algorithm (EM), regressive method, mean imputation, delete method, and Markov Chain Monte Carlo (MCMC) were used to supplement missing data respectively. The results: of different methods were compared according to distribution characteristics, accuracy and precision. Results HIV VL data could not be transferred into a normal distribution. All the methods showed good results in iterating data which is Missing Completely at Random Mechanism (MCAR). For the other types of missing data, regressive and MCMC methods were used to keep the main characteristic of the original data. The means of iterating database with different methods were all close to the original one. The EM, regressive method, mean imputation, and delete method under-estimate VL while MCMC overestimates it. Conclusion: MCMC can be used as the main imputation method for HIV virus loading missing data. The iterated data can be used as a reference for mean HIV VL estimation among the investigated population.

[Effect of data missing on population based viral load survey in HIV infected men who have sex with men sampled in 16 large cities, China].

Objective: To analyze the effect of missing data in population based viral load (PVL) survey in HIV infected men who have sex with men (MSM) sampled in 16 cities in China. Methods: The database of 3 virus load sampling survey conducted consecutively in HIV infected MSM population in 16 large cities (Beijing, Shanghai, Nanjing, Hangzhou, Wuhan, Chongqing, Kunming, Xi'an, Guangzhou, Shenzhen, Nanning, Urumuqi, Harbin, Changchun, Chengdu and Tianjin) during 2013-2015 was used. SPSS 17.0 software was used to describe distribution of the missing data and analyze associated factors. Results: A total of 12 150 HIV infected MSM were randomly selected for the surveys, in whom, 9 141 (75.2%) received virus load tests, while 3 009 (24.8%) received no virus load tests, whose virus load data missed. The virus load data missing rates in MSM with or without access to antiretroviral therapy (ART) were 11.5% (765/6 675) and 39.4% (2 060/5 223) respectively, and the virus load data missing rates were 21.9% (1 866/8 523) and 28.4% (959/3 374), respectively, in local residents and non-local residents (migrants). Conclusions: The analysis indicated that the data missing occurred in the virus load survey in HIV infected MSM population. ART status and census registering status were the main influencing factors. Data missing could influence the accurate evaluation of community viral load (CVL) and population viral load(PVL) levels in HIV infected MSM in China.

[Effects of botulinum toxin type A injection for pathological characteristic of calf in rats with spinal cord injure].

Objective: To explore the effect of BoTN-A on pathological characteristics of calf (GM) and motor function of ankle dorsiflexors in SCI model rats. Methods: Thirty-six SD male rats (weight 260-280 g) were randomly allocated into normal control group and 12w-control group, NS-injection group and BT-injection group in this study.NS/BT-injection groups were divided into two subgroups separately (2w-NS, 2w-BT, 8w-NS, 8w-BT). No injection was applied in normal control group or 12w-control group.Saline/BoTN-A was injected in right GM in NS/BT-injection group at two different time points(2w, 8w). GM and Sol on right side of rats would be forwarded for pathologicalexaminations, such as muscle weight, myosin heavy chain (MyHC) electrophoretic analysisat the 12th week. Results: Compared with the other three groups, the muscle weights of GM and Sol in the BT-injection group significantly decreased.MyHC type ratioof GM and Sol on the right side in the BT-injection group also significantlychanged.According to subgroup comparisons, MyHC type ratio of GM and Sol on the injectedside in the 2w-BT subgroup was significant different from that of the 8w-BT subgroup.MyHC type ratios of GM on the non-injected side in the BT injection group also changed more than normal control group.The change of MyHC type ratio of non-injected GM was significantly higher in the 2 week-BT subgroup than that in the 8-week subgroup. Conclusions: BoNT-A intervention resulted in pathological changes not only in the injected GM in SCI rats, but also in non-injected GM and non-injected Sol.The effects of earlier (2 weeks) BoTN-A intervention on pathologic characteristicsof GM and Sol were larger than that of later intervention.