[Retrospective analysis of diagnosis and treatment of tuberculosis in designated medical institutions in China from 2017 to 2022]

Objective: To understand the status of tuberculosis diagnosis and treatment capacity and the development and changes of tuberculosis diagnosis and treatment in provincial and municipal designated medical institutions in China from 2017 to 2022, so as to provide a basis for the formulation of relevant policies for the improvement and development of designated medical institutions for tuberculosis and the tuberculosis prevention and treatment service system, and to provide reasonable support for further strengthening the capacity of designated medical institutions for tuberculosis. Methods: This study was initiated and carried out by Beijing Chest Hospital affiliated to Capital Medical University/Clinical Center for Tuberculosis Prevention and Control of China CDC (hereinafter referred to as "Clinical Center") by means of questionnaire survey, and the investigation was carried out from March to November 2023. During this period, the clinical center distributed questionnaires to the hospital member units of "Beijing Tuberculosis Diagnosis and Treatment Technology Innovation Alliance", retrospectively collected their tuberculosis-related diagnosis and treatment data from 2017 to 2022, and used descriptive statistical methods to analyze the number of tuberculosis beds, outpatients and hospitalizations in medical institutions. The results were expressed in absolute numbers (percentages), and three-line tables, bar charts and line charts were drawn to describe the analysis results and changing trends. Results: The 54 medical institutions surveyed in this survey included 21 provincial-level designated medical institutions and 33 prefecture-level designated medical institutions. Most medical institutions have set up clinical departments, auxiliary departments and functional departments to undertake public health tasks of infectious diseases. The tuberculosis laboratory in the hospital has a comprehensive ability and has the detection technology needed for most tuberculosis diagnosis; The number of tuberculosis beds, children's tuberculosis beds and ICU beds all showed an increasing trend from 2017 to 2022. The proportion of tuberculosis beds in the hospital decreased slightly, from 39.31% in 2017 to 34.76% in 2022, showing a slight downward trend. Compared with the hospital surveyed, the number of tuberculosis outpatients in 2019 was 562 029, and the number of outpatients in 2020-2022 was 462 328, 519 630 and 424 069 respectively, which was significantly lower than that in 2019. The number of tuberculosis outpatients in medical institutions decreased significantly from 2020 to 2022. By analyzing the proportion of patients with different types of tuberculosis, the proportion of sensitive tuberculosis outpatients in 2017-2022 decreased from 84.49% in 2017 to 78.05% in 2022, showing a downward trend year by year. The proportion of patients with multidrug-resistant/ rifampin-resistant tuberculosis increased from 2.03% in 2017 to 7.18% in 2022. From 2017 to 2019, the total number of inpatients with tuberculosis showed an upward trend. Compared with 2019, the number of inpatients in 2020, 2021 and 2022 showed a downward trend, and the decline in 2020 was large (down 14.94% compared with 2019). Among the inpatients, the absolute number and proportion of patients with sensitive pulmonary tuberculosis remained relatively stable, and the number and proportion of inpatients with multidrug-resistant/rifampin-resistant pulmonary tuberculosis increased year by year. Conclusions: Most medical institutions have the capacity to carry out routine diagnosis and treatment of tuberculosis, but the public health function needs to be strengthened. The transformation of medical institutions requires proper guidance and adequate support. During 2019-2022, most medical institutions were affected by the COVID-19 epidemic, and their tuberculosis diagnosis and treatment work also changed to varying degrees. During this period, hospitals took various measures to overcome difficulties and tried their best to maintain the normal development of tuberculosis diagnosis and treatment, and the tuberculosis diagnosis and treatment work of various institutions gradually resumed in 2022.

[Prediction of prognosis of patients with radical resection of intrahepatic cholangiocarcinoma based on single cell omics]

Objectives: To analyze the survival benefit of intrahepatic cholangiocarcinoma (ICC) radical resection based on single cell omics. Methods: This is a retrospective case-series study. ICC single-cell sequencing was integrated from four data sets in the Gene Expression Omnibus Database, with a total of 46 patients undergoing radical resection, to explore the characteristics of the microenvironment. Microarray data of 100 ICC cases was analyzed in the EMBI database with survival data. The infiltration abundance of each epithelial cell cluster was calculated in each microarray data sample using the ssGSEA algorithm. The key epithelial cell cluster associated with poor patient outcomes was explored. The clinical value of key marker genes in this subgroup was studied. Prognostic marker genes were selected using the univariate and multivariate Cox proportional hazards(CoxPH) model. The The CoxPH model was constructed by the target genes and a nomogram was drawn. Kaplan-Meier survival analysis was used to verify the relationship between score and prognosis of patients. The predictive power of the model was evaluated by receiver operating characteristic(ROC) curves, calibration curves, and decision curve analysis (DCA). Results: Epithelial cell clusters infiltrated almost exclusively in tumor tissue. The MT2A+ epithelial cell subset was associated with a poorer prognosis for patients with a high invasion abundance and patients characterized by infiltration of this group were defined as antioxidant. After screening marker genes in this cluster using a univariate and multivariate CoxPH model, the following genes were found to be independent prognostic factors: FILPIL, NFKBIA, PEG10, SERPINB5. The CoxPH model was constructed using the four gene expression levels, and the survival rate of patients in the high-risk group was significantly lower than those in the low-risk group (all P<0.05). The constructed nomogram had good discrimination and validity. The ROC curve showed that the predicted area under the curve was 0.779, 0.844 and 0.845 at 1, 3 and 5 years, respectively. Compared to clinical indicators, the model had better predictive power using the calibration curve and the DCA test. Conclusions: The MT2A+ epithelial cell group may be associated with the prognosis of patients with ICC, and the concept of ICC tissue typing of antioxidant and non-antioxidant types is proposed. The type of antioxidant may predict the poor prognosis of the patients, and postoperative adjuvant therapy and other means could be considered to improve the survival of the patients.

[New advances in the diagnosis and treatment of intrahepatic cholangiocarcinoma]

Intrahepatic cholangiocarcinoma (ICC) is a type of primary liver cancer, which has shown an increasing trend in incidence and mortality in recent years, with a poor prognosis. The clinical diagnosis and treatment of ICC currently face the challenges of low detection rate, high mortality rate, poor treatment outcome, and urgently need more in-depth research to promote the improvement of clinical diagnosis and treatment level. In recent years, ICC diagnosis and treatment related research has made new progress in many aspects, and the knowledge about these new clinical diagnosis and treatment advances should be updated in a timely manner. This article reviewed the latest research results in recent years, summarized some new views on ICC typing, prevention and diagnosis staging that have been proposed recently, as well as the new progress made in surgical treatment and systemic treatment, and briefly discussed the potential of ICC individualized precision treatment and the occurrence of rare complications caused by combined treatment.

Fermented rape pollen powder can alleviate benign prostatic hyperplasia in rats by reducing hormone content and changing gut microbiota

Benign prostatic hyperplasia (BPH) can cause urethral compression, bladder stone formation, and renal function damage, which may endanger the life of patients. Therefore, we aimed to develop plant-based preparations for BPH treatment with no side effects. In this study, the Lactiplantibacillus plantarum 322Hp, Lactobacillus acidophilus 322Ha, and Limosilactobacillus reuteri 322Hr were used to ferment rape pollen. The fermented rape pollen was subsequently converted into fermented rape pollen powder (FRPP) through vacuum freeze-drying technology. After fermenting and drying, the bioactive substances and antioxidant capacity of FRPP were significantly higher than those of unfermented rapeseed pollen, and FRPP had a longer storage duration, which can be stored for over one year. To investigate the therapeutic effect of FRPP on BPH, a BPH rat model was established by hypodermic injection of testosterone propionate. The BPH rats were treated differently, with the model group receiving normal saline, the positive control group receiving finasteride, and the low, medium, and high dose FRPP group receiving FRPP at doses of 0.14 g/kg/d, 0.28 g/kg/d, and 0.56 g/kg/d, respectively. The results indicate that medium dose FRPP reduced the levels of hormone such as testosterone, dihydrotestosterone, and oestradiol in rats with BPH by about 32%, thus bringing the prostate tissue of BPH rats closer to normal. More importantly, medium dose FRPP treatment had a significant effect on the composition of gut microbiota in rats with BPH, increasing the levels of beneficial genera (such as Coprococcus and Jeotgalicoccus), and decreasing the levels of harmful pathogens (such as Turicibacter and Clostridiaceae_Clostridium) in the gut. This study showed that medium dose FRPP reduced the hormone level and regulated the unbalanced gut microbiota in BPH rats, thereby alleviating BPH.

[Clinical features and prognostic factors of elderly patients with mantle cell lymphoma]

Objective: To examine the clinical characteristics and prognostic factors of elderly patients with mantle cell lymphoma (MCL) and the impact of nutrition and underlying diseases on the prognosis of elderly patients with MCL. Methods: retrospectively analyzed 255 elderly patients with MCL from 11 medical centers, including Peking University Third Hospital between January 2000 and February 2021. We analyzed clinical data, such as age, gender, Mantle Cell Lymphoma International Prognostic Index score, and treatment options, and performed univariate and multivariate prognostic analysis. We performed a comprehensive geriatric assessment on elderly MCL patients with medical records that included retraceable underlying disease and albumin levels, and we investigated the impact of basic nutrition and underlying disorders on MCL prognosis in the elderly. Results: There were 255 senior individuals among the 795 MCL patients. Elderly MCL was more common in males (78.4%), with a median age of 69 yr (ages 65-88), and the majority (88.6%) were identified at a late stage. The 3-yr overall survival (OS) rate was 42.0%, with a 21.2% progression-free survival (PFS) rate. The overall response rate (ORR) was 77.3%, with a 33.3% total remission rate. Elderly patients were more likely than younger patients to have persistent underlying illnesses, such as hypertension. Multivariate analysis revealed that variables related with poor PFS included age of ≥80 (P=0.021), Ann Arbor stage Ⅲ-Ⅳ (P=0.003), high LDH level (P=0.003), involvement of bone marrow (P=0.014). Age of ≥80 (P=0.001) and a high LDH level (P=0.003) were risk factors for OS. The complete geriatric assessment revealed that renal deficiency was associated with poorer OS (P=0.047) . Conclusions: Elderly MCL patients had greater comorbidities. Age, LDH, renal function, bone marrow involvement, and Ann Arbor stage are all independent risk factors for MCL in the elderly.

[Pancreatic pseudocyst after pegaspargase treatment in six children]

Objective: To investigate the clinical characteristics and treatment of pancreatic pseudocyst after pegaspargase treatment in children. Methods: The clinical data of 6 children with pancreatic pseudocyst after pegaspargase treatment in the Department of Pediatrics in Peking University Third Hospital from July 2018 to February 2021 were analyzed retrospectively. Results: There were 4 males and 2 females, and their age of onset was 9.5 (5.8, 13.0) years. The total number of pegaspargase applications was 2.5 (2.0, 3.5) times. The course from the last dose of pegaspargase to the onset of pancreatitis was 11.0 (9.0, 17.2) days, and 42.5 (35.0, 129.5) days from the onset of pancreatitis to the diagnosis of pancreatic pseudocyst. Abdominal pain was the most prominent manifestation of pancreatitis (6/6). All of the 6 children were asymptomatic when pancreatic pseudocyst was noted, and were treated conservatively at first, but one case later developed intermittent abdominal distension or nausea after eating. All the cases had pancreatic pseudocyst enlargement during the conservative treatment. Three children were treated with endoscopic ultrasound-guided transgastric drainage, and the cyst disappeared from 10 days to 4 months after the operation. The other 3 children received endoscopic retrograde cholangiopancreatography (ERCP)-guided transpapillary drainage, but one of them turned to surgery due to pancreatic duct stricture, and in the rest 2 children the cyst disappeared at 1 and 3 months after operation respectively. Regarding safety issues, 1 child who received ERCP-guided transpapillary drainage had acute postoperative pancreatitis, which were improved after treatment, and the other 5 had no complications. Conclusions: Pancreatic pseudocyst after pegaspargase chemotherapy can be asymptomatic in the early stage, and should be diagnosed with a history of pegaspargase treatment and timely imaging examination. Conservative treatment is the first choice for asymptomatic pseudocyst. When the pseudocyst enlarges, different endoscopic drainage treatments are required according to whether the pseudocyst is connected with the main pancreatic duct.

Genome-wide association studies uncover genes associated with litter traits in the pig

Litter traits are critical economic variables in the pig industry as they represent a production indicator that can serve to determine sow fertility. In this study, a genome-wide association study on litter traits, including total number born (TNB), number born alive (NBA), litter birth weight (LBW), average birth weight (ABW), and piglet uniformity (PU), was carried out on two pig breeds (Yorkshire and Landrace). A total of 3 637 pigs of both breeds were genotyped using the GeneSeek GGP Porcine 50K SNP BeadChip. A mixed linear model (MLM) and fixed and random model circulating probability unification (FarmCPU) were employed in the genome-wide association studies for litter traits using combined data from the two pig breeds and data from each breed separately. Additionally, the heritability of traits was estimated using three methods-pedigree-based best linear unbiased prediction (PBLUP), genomic best linear unbiased prediction (GBLUP), and single-step best linear unbiased prediction (ssGBLUP)-and was found to lie between 0.065 and 0.1289, 0.0478 and 0.0938, 0.0793 and 0.0935, 0.1862 and 0.2163, and 0.0327 and 0.0419 for TNB, NBA, LBW, ABW, and PU, respectively. We also compared the genomic prediction accuracies and unbiasedness for litter traits of the three BLUP models. Our results indicated that the ssGBLUP method provided higher predictive accuracies and more rational unbiasedness compared with the PBLUP and GBLUP methodologies. Furthermore, based on their possible roles, eight candidate genes (INHBA, LEPR, HDHD2, CTNND2, RNF216, HMX1, PAPPA2, and NTN1) were identified as being linked with litter traits. In the middle of the test, these genes were found to be connected with pig metabolism and ovulation rate. Our results provide the insights into the genetic architecture of litter traits in pigs, and the potential single nucleotide polymorphisms (SNPs) and candidate genes identified may benefit economic profits in pig-breeding industry and contribute to improve litter traits.

[Expression and clinical significance of COL1A1 and COL1A2 genes in malignant pleural mesothelioma tissues]

Objective: To investigate the expression levels and clinical significance of collagen typeⅠ α1 chain (COL1A1) and collagen type Ⅰ α2 chain (COL1A2) in malignant pleural mesothelioma (MPM) tissues. Methods: In January 2020, MPM tissues and adjacent normal pleural tissues were collected from 26 MPM patients, and the expression levels of COL1A1 and COL1A2 genes in the tissues were determined by quantitative reverse transcription PCR, and the efficacy of both levels in diagnosing MPM was assessed using receiver operating characteristic (ROC) curves. The relationship between COL1A1 and COL1A2 gene expression and clinicopathological features was analyzed by the Cancer Genome Atlas (TCGA) database, and the relationship between the expression levels of both and overall survival (OS) and disease-free progression survival (DFS) of MPM patients was dynamically analyzed by gene expression profiling, and the factors affecting the prognosis of MPM patients were explored by Cox proportional risk regression model. The TIMER 2.0 platform was used to explore the relationship between COL1A1 and COL1A2 gene expression in MPM and tumor immune infiltrative cells. Results: Compared with normal pleural tissues, the expression of COL1A1 and COL1A2 genes was significantly increased in MPM tissues (P<0.01) , and their expression was positively correlated (P<0.001) . The ROC curves showed that the area under the curve for COL1A1 and COL1A2 expression levels diagnostic of MPM was 0.900 and 0.897, respectively. The expression of COL1A1 gene was correlated with tumor type in MPM patients (P<0.05) , and COL1A2 gene expression was correlated with T stage in MPM patients (P<0.05) . Both COL1A1 and COL1A2 gene expression were associated with OS in MPM patients (Logrank P<0.05) , but there was no significant correlation with DFS (Logrank P>0.05) . Cox multivariate analysis showed that patients with high COL1A1 and COL1A2 gene expression and biphasic mixed MPM had a higher risk of death (P<0.05) . TIMER 2.0 platform analysis showed that COL1A1 and COL1A2 gene expression in MPM patients was positively correlated with macrophages, COL1A2 gene expression in MPM was negatively correlated with neutrophils (P<0.05) . Conclusion: High expression of COL1A1 and COL1A2 genes in MPM tissues is valuable for diagnosis, disease prediction and prognostic assessment of MPM, and both may jointly contribute to the development of MPM.

[Early onset Epstein-Barr virus-negative diffuse large B cell lymphoma after bilateral lung transplantation: a case report]

Lymphoma after solid organ transplantation is one of the manifestations of post-transplant lymphoproliferative disorders(PTLD). Here we reported a 39-year-old male patient presented with intermittent fever, markedly elevated level of peripheral blood lymphocytes and lactate dehydrogenase(LDH), rapid decrease in hemoglobin and platelet count ten months after bilateral lung transplantation. After systematic evaluation, the patient excluded infectious diseases. Positron emission tomography-computed tomography (PET/CT) revealed diffuse increasing of standard uptake value in bones throughout the body. The bone marrow aspiration, flow cytometric analysis and histopathology confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) with negative Epstein-Barr virus-encoded small RNA (EBER) hybridization in situ. Meanwhile, complicated hemophagocytic lymphohistiocytosis was also diagnosed in the patient based on hypertriglyceridemia, abnormally elevated level of serum ferritin and solvable CD25 (sCD25). Treatment regimen included reduction of immunosuppression, anti-CD20 antibody (CD20⁺ B cell inhibitor, rituximab) and etoposide. Repeated PET/CT and bone marrow biopsy showed complete remission of lymphoma after 4 months of therapy.

[Time distribution of positive nucleic acid detection in imported cases infected with SARS-CoV-2 in China]

Objective: To analyze the time distribution of the first positive nucleic acid detection in imported cases infected with SARS-CoV-2 reported nationwide in China and provide references for further improvement of the prevention and control of COVID-19 in international travelers. Methods: The data of imported cases infected with SARS-CoV-2 reported by provinces from 24 July 2020 and 23 July 2021 were collected for the analysis on the time distribution of the first positive nucleic acid detection after entering China. Results: A total of 7 199 imported cases infected with SARS-CoV-2 were reported in 28 provinces during 24 July 2020 to 23 July 2021. The median interval (Q₁, Q₃) from the entry to the first positive nucleic acid detection of SARS-CoV-2 was 1 (0, 5) day. The imported cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry accounted for 95.15% (6 850/7 199) and 4.85% (349/7 199) respectively. Among these cases, 3.65% (263/7 199), 0.88% (63/7 199) and 0.32% (23/7 199) had the first positive nucleic acid detections within 15-21 days, 22-28 days and 28 days later after the entry respectively. The proportion of asymptomatic infections were 47.24% (3 236/6 850) and 63.61% (222/349) among the cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry respectively. A total of 39.54% (138/349) of cases infected with SARS-CoV-2 with the first positive nucleic acid detections 14 days later after the entry had inter-provincial travel after the discharge of entry point isolation. Conclusions: About 5% of the imported cases infected with SARS-CoV-2 were first positive 14 days later after the entry. In order to effectively reduce the risk of domestic COVID-19 secondary outbreaks caused by imported cases, it is suggested to add a nucleic acid test on 8^th -13^th day after the entry.

[The value of color doppler ultrasonography in the diagnosis of endograft infections following endovascular aneurysm repair]

Objective: To study the value of color doppler ultrasonography (CDU) in the diagnosis of endograft infections following endovascular aneurysm repair (EVAR). Methods: The retrospective analysis of post-EVAR stent infections identified by computed tomography angiography (CTA) was conducted at the First Affiliated Hospital of Sun Yat-sen University from January 2010 to December 2020. There were 16 males and 4 females, aged from 49 to 86 years. All the patients were detected by CDU. The endoleak, bubbles, abscess, hematoma, aortic intestinal fistula (AEF) and occlusion of stent detected by CTA and CDU were analyzed and compared. Results: Among 20 patients, 9 cases with endoleak were detected by CTA, while CDU showed 8 cases with endoleak. The rate of missed diagnosis was 1/9. The misdiagnosis rate was 0, and the Youden index was 0.89. CDU detected 3 cases with type Ⅱ endoleak, and 1 case was missed when compared with CTA. Three cases with type Ⅰa and 2 cases with type Ⅰb were detected by CDU, which were consistent with those of CTA. CDU and CTA showed that there were no cases with type Ⅲ and type Ⅳ endoleaks. CDU detected 8 cases with bubbles in the sac. Compared with CTA, the rate of missed diagnosis was 2/10. The misdiagnosis rate was 0, and the Youden index was 0.80. The cases with abscess, hematoma, increasing size of the aneurysm, occlusion of stent and fluid sonolucent area in the sac detected by CDU were 8/20, 2/20, 4/20, 1/20, 2/20, which were consistent with CTA. CDU did not detect the 3 cases with aortoenteric fistula(AEF) which were identified by CTA. The follow-up of CDU showed that the extra-anatomic bypasses remained their patency in 5 cases, 1 case occurred bypass occlusion. The range of infectious area and bubbles reduced in 2 cases. There was no change of endoleak in 1 case. All the follow-up results were consistent with those of CTA. Conclusion: CDU can comprehensively evaluate the infection in and around the aneurysm in patients with stentinfection after EVAR, with a high auuraly, and has important clinical significance for the early diagnosis, treatment and prognosis of patients.

[Distribution and infectious characteristics of re-positive cases infected with SARS-CoV-2]

Domestic and foreign literatures related to the persistence of SARS-CoV-2 and the re-positive cases infected with SARS-CoV-2 were reviewed, and the characteristics and infectivity of the re-positive cases were analyzed to provide scientific evidence for the improvement of case management and the development of measures to stop the spread of SARS-CoV-2. Existing studies have shown that re-positive rate of SARS-CoV-2 ranged from 2.4% to 19.8%, the median of interval between re-positive detection and discharge was 4-15 days. Following the second course of the disease, the anti-SARS-CoV-2 IgM, IgG and IgA positive rates of the cases were 11.11%-86.08%, 52.00%-100.00% and 61.54%-100.00% respectively, the total antibody and neutralizing antibody positive rates were 98.72% and 88.46%. The viral load of the re-positive cases was lower than that of in the initial infection. At least 3380 re-positive cases have been reported globally. SARS-CoV-2 strains were isolated from the samples of 3 re-positive cases (1 immunodeficiency case and 2 cases with abnormal pulmonary imaging). There were close contacts that were infected by an asymptomatic case taking immunosuppressive agents. In conclusion, the infectivity of re-positive cases infected with SARS-CoV-2 is generally very low. Rare re-positive cases infected with SARS-CoV-2 might cause further transmission. The management approach for the re-positive cases can be based on the assessment of the individual transmission risk according to the pathogen detection results.

[Prognostic value of the age-adjusted Charlson comorbidity index in patients over 60 years old with laryngeal squamous cell carcinoma]

Objective: To evaluate the value of the age-adjusted Charlson comorbidity Index (ACCI) in predicting the prognosis and guiding the clinical treatment of laryngeal squamous cell carcinoma (LSCC) in patients over 60 years old. Methods: Retrospective analysis of 249 cases of LSCC in Shanxi Provincial Cancer Hospital and First Hospital of Shanxi Medical University from 2008 to 2015 was performed. There were 234 males and 15 females, aged from 60 to 88 years. The clinical characteristics, treatment information and follow-up data were collected. ACCI was used to score the comorbidities of the patients. Receiver operating characteristic (ROC) curve was drawn and the patients were divided into high ACCI group and low ACCI group according to the cut-off value of ACCI. Prognostic factors were analyzed. Kaplan-Meier method was used for survival analysis, rank sum test was used for comparison between groups, χ² test was used for enumeration data. Results: Overall survival (OS) was 54.6%, progression-free survival (PFS) was 59.4%, and cancer-specific survival (CSS) was 58.6%. Both the median survival time and PFS time were 60 months. The best cutoff point of the ACCI group was 5. Cox multivariate analysis showed that ACCI was an independent risk factor for OS, PFS and CSS (OR=1.553, 1.499 and 1.534,respectively, all P<0.05). In the high ACCI group, OS (χ²=4.120 and 4.115,P<0.05) and CSS (χ²=4.510 and 5.009,P<0.05) of patients treated with surgery plus radiotherapy and patients with radiotherapy alone were better than those of patients with surgery alone (P<0.05). But in the low ACCI group, there was no significant difference in prognosis among the three treatment regimens (P>0.05). Conclusion: High ACCI offors important prognostic information for LSCC in patients over 60 years old, and can guide clinical treatment options.

[Timing of food introduction to the infant diet and risk of food allergy: a systematic review and Meta-analysis]

Objective: To evaluate the relationship between the timing of complementary feeding for infants and the occurrence of food allergy. Methods: The PubMed, Cochrane Library, China National Knowledge Infrastructure (CNKI), and WanFang Data database were searched for randomized controlled trials (RCTs) about the effects of early introduction of complementary foods in infants on the occurrence of food allergy. Papers published from the establishment of the databases to December 31, 2019 were extracted. The quality of the selected literature was evaluated using the risk-of-bias (ROB) tools in the Cochrane Handbook, and the RevMan 5.3 software was used for meta-analysis. For the complementary food analyzed in a few reports in literature, a systematic review was conducted. Results: A total of 8 RCTs were extracted, and the systematic review and Meta-analysis were carried out according to food types. The results of Meta-analysis showed that compared with late introduction (after 6 months of age), early introduction (before 6 months of age) of eggs (RR=0.60, 95%CI 0.46-0.79) could reduce the risk of egg allergy in infants. The subgroup analysis of the six studies about eggs demonstrated that in infants with a prior or family history of allergic diseases, the introduction of eggs before 6 months of age was associated with reduced risk of egg allergy (RR=0.55, 95%CI 0.40-0.75), and the introduction of raw eggs (RR=0.67, 95%CI 0.49-0.93) and small amount of eggs (equivalent to weekly protein 0-4 g) (RR=0.55, 95%CI 0.36-0.85) before 6 months of age were also associated with reduced risk of egg allergy. In addition, egg supplementation during 4-6 months of age reduced the occurrence of egg allergy compared with supplementation before 4 months of age (RR=0.58, 95%CI 0.43-0.78). The systematic review found no conclusive relationship between early peanut introduction and peanut allergy, nor the correlation between early cow's milk protein introduction and cow's milk protein allergy (P>0.05). Conclusion: Early introduction (before 6 months of age) of eggs in infants' complementary foods can prevent infant egg allergy, but the limitations of the study need to be considered.

[A comparative study of the effects of different treatment strategies on postoperative anal function and quality of life in patients with complete obstructive left hemicolon cancer]

Objective: To compare the effects of 3 treatment strategies (emergent surgery, self-expanding metallic stents, self-expanding metallic stents plus neoadjuvant chemotherapy) on postoperative anal function and quality of life in patients with complete obstructive left hemicolon cancer. Methods: A retrospective cohort study was conducted. Clinical data of patients with complete obstructive left hemicolon cancer admitted to General Surgery Department of Beijing Chaoyang Hospital between January 2017 and October 2019 were retrospectively collected. Patient inclusion criteria: (1) complete obstructive left hemicolon cancer was confirmed through clinical manifestation and abdominal computed tomography; (2) adenocarcinoma was confirmed by postoperative pathology; (3) emergent radical resection of primary tumor was performed with temporary stoma, or radical resection of primary tumor and primary anastomosis was performed without stoma, 7 to 14 days after completion of insertion of self-expanding metallic stents. Patients who did not receive stoma reversion after emergent operation were excluded. According to different therapies, patients were divided into three groups: emergent surgery (ES) group, self-expanding metallic stents (SEMS) group and self-expanding metallic stents plus neoadjuvant chemotherapy (SEMS+NAC) group. Wexner score for incotinence (higher score indicates the worse anal function), Vaizey score (>10 indicates fecal incontinence) and low anterior resection syndrome (LARS) scale (higher score indicates the worse anal function) were applied to evaluate anal function of patients among groups at postoperative 1-, 6- and 12-month. EORTC QLQ-C30 questionnaire was used to assess the quality of life. Risk factors of decreased anal function were identified by logistic regression analysis. Results: A total of 72 patients were enrolled, including 27 (37.5%) patients in ES group, 23 (31.9%) in SEMS group and 22 (30.6%) in SEME+NAC group. The baseline characteristics including age, gender, tumor location, comorbidities, total blood loss, operation time and postoperative complications, were comparable among groups, except that the proportion of laparoscopic surgery was significantly lower in ES group (4/27, 14.9%) than that in SEMS (15/23, 65.2%) and SEMS+NAC group (16/22, 72.7%) with significant difference (P<0.001). The follow-up ended up to October 2020, and the overall follow-up rate was 79.2% (57/72). No significant differences existed in the Wexner score of patients among groups at postoperative 1-, 6- and 12-month (all P>0.05). The Vaizey scores at postoperative 1-month in ES, SEMS and SEMS+NAC group were 7 (0-17), 3 (0-7) and 4 (0-8) respectively with significant difference (H=18.415, P=0.001), and the scores in SEMS and SEMS+NAC groups were significantly lower than that in ES group (both P<0.05), while no significant difference existed between SEMS and SEMS+NAC group (P>0.05). Vaizey scores at postoperative 6- and 12-month among 3 groups were not significantly different (both P>0.05). The LARS scores at postoperative 1-month in ES, SEMS and SEMS+NAC groups were 20 (0-37), 15 (0-24) and 16 (0-28) respectively with significant difference (H=3.660, P=0.036), and the scores in SEMS and SEMS+NAC groups were significantly lower than that in ES group (both P<0.05), while no significant difference existed between SEMS and SEMS+NAC groups (P>0.05). LARS scores at postoperative 6- and 12-month among 3 groups were not significantly different (both P>0.05). The QLQ-C30 score revealed that the social function of patients in SEMS group and SEMS+NAC group was significantly better than that in ES group (both P<0.05), while no significant difference existed between SEMS and SEMS+NAC group (P>0.05). The logistic regression analysis revealed that only ES was an independent risk factor of decreased anal function (OR=2.264, 95% CI: 1.098-4.667, P=0.027). Conclusion: Compared to ES, SEMS may improve quality of life and short-term anal function of patients with complete obstructive left hemicolon cancer.

[Investigation of incidence of acute respiratory infection and healthcare-seeking behavior in period of COVID-19 epidemic]

Objective: To analyze the incidence of acute respiratory infection (ARI) and related healthcare seeking behaviors in population in the period of COVID-19 epidemic in China. Methods: According to the province specific cumulative incidence rates of COVID-19 reported as of March 31, 2020, the low, medium and high-risk areas were classified. In these areas, a stratified two stage cluster random sampling method was used to select participants for face-to-face questionnaire surveys. Data on the incidence of ARI and related healthcare seeking behaviors in community residents during COVID-19 epidemic period were collected to calculate the attack rate of ARI and related healthcare seeking rate. Logistic regression method was used to explore the influencing factors for ARI incidence and healthcare seeking behavior. Results: A total of 34 857 community residents were surveyed, in whom 647 (1.9%) reported that they had ARI symptoms during the COVID-19 epidemic period, and 241 (37.2%) had healthcare seeking behaviors. In terms of the incidence of COVID-19-related ARI, in high-risk area, the risk of COVID-19-related ARI was 1.36 times (95%CI: 1.12-1.65) than that in low-risk area; among different age groups, the risk of COVID-19-related ARI in age groups 20-39 years, ≥60 years was 1.80 times (95%CI: 1.29-2.59) and 1.63 times (95%CI: 1.14-2.40) than that in age group 1-9 years; the risk of COVID-19-related ARI in people with underlying diseases was 1.53 times (95%CI: 1.23-1.89) than that in those without underlying diseases; the risk of COVID-19-related ARI in people with contacts with confirmed cases of COVID-19 and people with fever or respiratory symptoms was 1.53 times (95%CI: 1.01-2.27) and 6.60 times (95%CI: 5.05-8.53) than those in people without these contacts. The healthcare seeking rate in COVID-19-related ARI patients with exposures to those with fever or respiratory symptoms was 1.68 times (95%CI: 1.05-2.70) than that in such patients without the exposures. Conclusions: The attack rate of COVID-19-related ARI was affected by the local epidemic level of COVID-19, and in high-risk area, the attack rate of COVID-19-related ARI was also high. The healthcare seeking rate in patients with COVID-19-related ARI was low. Therefore, it is necessary to encourage the healthcare seeking in people with ARI in COVID-19 pandemic period.

[Analysis on prevention and control of some infectious diseases in the elderly aged 60 years and above in China and countermeasure recommendation]

As the progress of population aging in China, the proportion of elderly population is increasing. Both chronic diseases and infectious diseases can threaten the health of the elderly. There are many kinds of infectious diseases, including vaccine preventable infectious diseases affecting the health of adults, such as influenza, pneumococcal diseases and herpes zoster. In addition, the newly emerged COVID-19 has caused a pandemic in the world, resulting the highest proportion of deaths occurred in the elderly and posing a serious threat to the health of the elderly. This paper mainly summarizes the prevention and control of vaccine preventable diseases and COVID-19 to which the elderly are susceptible, analyzes the infectious disease problems affecting the health of elderly population, and recommends countermeasures for the prevention and control of these diseases in elderly population.

[Progress in research of specific antibody dynamic characteristics in patients with COVID-19]

COVID-19 is an emerging infectious disease caused by SARS-CoV-2. After the infection of the virus, the host immune system is stimulated to produce multifarious specific antibodies to decrease or eliminate effects of the pathogen. Study of the specific antibodies dynamic characteristics in patients with COVID-19 is very important for the understanding and diagnosis of the disease, research and development of vaccine, and planning of prevention and control strategy. This paper reviews and summarizes the domestic and oversea research on dynamic characteristics of specific antibodies of COVID-19 patients, including the antibody producing, duration and level, and its possible influencing factors in order to improve the understanding of the immunological characteristics of COVID-19.

[Advance on the infectivity of SARS-CoV-2 infection at different stages]

The studies on infectiousness of person infected with SARS-CoV-2 at different stages of illness are an important basis for making effective prevention and control measures such as investigating the infectious source, determining the scope of close contacts and the timing of case isolation. This review discusses the infectiousness of cases infected with SARS-CoV-2 in the incubation period, symptomatic period and convalescent period by reviewing national and international literatures, technical and professional guidelines. Existing researches suggest that the infectious viruses could be isolated at the end of the incubation period as well as since illness onset, and viral load in upper respiratory tract swabs reached the peak on day 4-6 after illness onset and thereafter began to decline, implying the infectiousness was relatively strong at the end of incubation period and within one week after illness onset. Although there were a few cases who tested positive for SARS-CoV-2 after recovery, no evidence was found to indicate these cases can cause the transmission.

Characteristics of Mandibular Canal Branches Related to Nociceptive Marker

It is difficult to correlate the direction of mandibular canal branches (MCBs) with altered sensation in dental treatments. In contrast, calcitonin gene-related peptide (CGRP) is related to vasodilation, bone formation, and the interaction with the peripheral nervous system. Therefore, we investigated the detailed morphological characteristics of MCBs using cone-beam computed tomography (CBCT) and observation of the CGRP distribution around the MCB. The MCB measurements were evaluated using principal component analysis (PCA) to identify morphological correlations. A total of 168 sides of mandibles from 84 cadavers were analyzed in this study. Most of the MCBs were primarily in the direction of the clock model from X to XI in sagittal sections and XII to I in coronal sections of the mandible. The structure of the MCB was divided into the fine canal branch (60.4%, 223/369), partial branch (24.4%, 90/369), and no canal branch (15.2%, 56/369). PCA indicated that the measurement element with the MCB and its structures were correlated in contrast to tooth factors. Positive CGRP reactions were clearly observed in the no-canal branch group compared to other groups. These data provide useful suggestions for MCB dynamics and information for clinical dental treatment.

[Pilot surveillance and evaluation of influenza-like illness based on automatic computer analysis of electronic medical record in sentinel hospital]

Objective: To compare the accuracy of influenza-like illness (ILI) surveillance by automatic computer analysis based on electronic medical records and by doctor's report. Methods: A total of 3 542 patients who presented to Yichang Central Hospital fever clinic, respiratory department or emergency department between April to October 2019 with an ICD-10 code for acute respiratory illness (J00-J22) and complete electronic medical information of ILI related syndromes were drawn as the study sample. Taking the classification of the study sample according to the ILI case definition by influenza surveillance professionals as the gold standard, draw the receiver operating characteristic (ROC) curve and calculate sensitivity, specificity, diagnostic consistency to compared the accuracy of ILI surveillance by automatic computer analysis and by doctor's report. Results: Median age of 3 542 cases was 30 (24, 38) years old; 1 179 cases (33.29%) compliance with the case definition, ILI reported by doctors was 1 306 cases (36.87%), and computer automatic identification ILI were 1 150 cases (32.47%); 1 391 (39.27%) cases were men. The results of automatic computer analysis and doctor report consistency of kappa values with gold standard judgment were 0.97 and 0.66 respectively; area under the ROC curve was 0.98 and 0.84, respectively. And the sensitivity and specificity of automatic computer analysis were higher than that of doctor's report (all P values were <0.001), the sensitivity was 96.95% and 82.27%, and the specificity was 99.70% and 85.78%, respectively. Conclusion: The automatic computer analysis based on electronic medical records can identified ILI cases with good sensitivity and specificity in ILI case surveillance.

[The value of color doppler ultrasonography in the diagnosis of impending ruptured abdominal aortic aneurysm]

Objective: To study the value of color doppler ultrasonography (CDU) in diagnosis of impending ruptured abdominal aortic aneurysm (IRAAA). Methods: A total of 35 cases with IRAAA which were identified by CDU in our department from June 2014 to June 2019 were retrospectively analyzed. All the patients were detected by computed tomographic angiography (CTA). The types, length of the neck of aneurysm, largest diameter, thrombosis, involvement of common iliac artery and impending ruptured conditions were compared. The postoperative patients were followed-up by CDU and CTA (mean time was 2.6 months). Results: Among 35 patients, CDU diagnosed that 5 cases were pararenal types and 30 cases were infrarenal types. CTA showed that 4 cases were pararenal types and 31 cases were infrarenal types. The misdiagnosis rate of CDU was 2.9% (1/35). CDU showed that bilateral common iliac arteries were involved in 21 cases, right common iliac arteries were involved in 3 cases, and left common iliac arteries were involved in 2 cases. CTA detected the same results. There was no statistical difference between CDU and CTA for detection of the largest anteroposterior diameter, transverse diameter and the thickness of thrombosis (P values were 0.354, 0.310 and 0.865). There was statistical difference in the detection of the length of the aneurysm's neck (P=0.006). CDU showed 3 cases of focal wall discontinuity, 4 cases of hyperattenuating crescent sign, 3 cases of thrombus fissuration and 2 cases of saclike protuberance, which were consistent with the detection of CTA. CDU showed that locally thin wall of aneurysm was detected in the rest of 23 cases. CTA showed 2 patients were negative. The misdiagnosis rate of CDU was 5.7% (2/35). Three cases did not undergo surgery. Open repairs (OR) were performed in 5 cases. Endovascular aneurysm repairs (EVAR) were performed in 27 cases. The postoperative patients were followed up by CDU and CTA at 1 month, 3 months, 6 months and 12 months. All the artificial blood vessels and stents were patent. Endoleak was observed in 5 cases. Aneurysm sac thrombosis was found in the rest of the cases. Conclusions: CDU plays an important role in the analysis and diagnosis of the size, range, and the impending ruptured symptoms of the aneurysm. It provides a reliable basis for IRAAA screening, diagnosis and postoperative follow-up, and has important clinical value.

[Relationship between gene polymorphism at rs2228055 locus in the exon region of interleukin-10 receptor A and susceptibility to food allergy in children]

Objective: To investigate the relationship between gene polymorphism of rs2228055 locus in the exon region of interleukin-10 receptor A (IL-10RA) and susceptibility to food allergy in children. Methods: This was a case-control study. The food allergy group had 150 children who were diagnosed with food allergy in the Pediatric Food Allergy Clinic of Peking University Third Hospital from August 1, 2017 to November 30, 2018. Another 150 healthy children attended Child Health and Development Center in the same hospital were selected as control group. The genotypes of rs2228055 locus in both groups were detected by PCR re-sequencing. And the genotypes and allele frequencies of rs2228055 locus were compared between these two groups, as well as between food allergy children with positive and negative allergen specific IgE, and between those with and without involvement of different organs. Using the computer virtual mutation to stimulate the changes of amino acid caused by change of rs2228055 locus allele, to analyze the effect of amino acid changes on the structure of IL-10RA. The chi-square test was used for comparison between groups. Results: (1) There were 92 males and 58 females in food allergy group, and 86 males and 64 females in control group, without any statistically significant difference (χ(2)=0.497, P=0.481). The ages of the two groups were 4.2 (0.1-15.0) and 8.0 (0.1-14.0) years old, respectively, the difference was statistically significant (Z=-6.109, P<0.01). (2) The genotype frequencies of rs2228055 locus in the food allergy group and the control group were as follows: AA accounted for 73 (48.7%) and 98 (65.3%), AG accounted for 62 (41.3%) and 42 (28.0%), and GG accounted for 15 (10.0%) and 10 (6.7%), respectively. The allele frequencies in the two groups were as follows: 208 (69.3%) and 238 (79.3%) for A, 92 (30.7%) and 62 (20.7%) for G, respectively. AG and GG genotype frequency and the allele G frequency in food allergy group were significantly higher than that in control group (χ(2)=8.501 and 7.862, P=0.014 and 0.005, respectively). (3) There were no significant differences in genotype frequencies and allele frequencies of rs2228055 locus of allergen-specific IgE-positive and negative food allergy children (all P>0.05). (4) There were no significant differences in genotype frequencies and allele frequencies of rs2228055 locus in the manifestations of skin, digestive system and respiratory system in food allergy children (all P>0.05). (5) The computer virtual mutation showed that the mutation energy was -0.08 without any increase in the stability of IL-10RA when the amino acid encoded by rs2228055 locus was changed from isoleucine to valine. Conclusions: The frequencies of genotype AG, GG and allele G of rs2228055 locus in the IL-10RA exon region in food allergy children are higher than that in non-allergic children, and those with the G allele are more likely to develop food allergy.

Clinical significance of perioperative EMT-CTC in rectal cancer patients receiving open/laparoscopic surgery

The objective of this study was to explore the clinical significance of perioperative CTCs (circulating tumor cells) counts and EMT-CTCs (epithelial-mesenchymal transition-CTCs) in rectal cancer patients. A total of 30 patients with rectal cancer who underwent radical resection of rectal cancer at the Guangxi Zhuang Autonomous Region People's hospital were enrolled. Five ml peripheral blood was withdrawn from 30 patients with rectal cancer before the operation and seven days after the operation and at the corresponding time also from 20 healthy volunteers. CanPatrol™ CTC detection technique was used to enrich and identify CTCs and IER3 expression simultaneously. We found out that the preoperative total CTCs were correlated with lymph node metastasis (p=0.008) and tumor size, and mixed CTCs were closely correlated with lymph node metastasis (p=0.009). The number of IER3-positive total CTCs and mesenchymal CTCs were statistically associated with tumor size, p=0.034 and 0.043, respectively. The number of CTCs varied significantly before and after the operation in all patients (p=0.049). There were significant differences in CTCs variations between the open operation group and the laparoscopic operation group. In the laparoscopic operation group, the average number of single-cell CTCs was 6.9 before operation and 3.5 after the operation (p=0.013). In the open operation group, the average number of single-cell CTCs was 5.9 before operation and 4.2 after the operation. To conclude, surgery is associated with a decrease of CTCs in rectal cancer patients, especially in patients receiving laparoscopic surgery. The number of CTCs before the operation in rectal cancer patients is related to the size of tumors and regional lymph node metastasis. CTCs detection and characterization may be useful for clinical staging and lymph node dissection during operation.

[Five million wear simulation and particle analysis of carbon-based nano-multilayer coatings titanium alloy femoral head]

Objective: To analyze the wear debris characteristics ofcarbon-based nano- multilayer coatings on Ti(6)Al(4)V alloys and compared with the cobalt chromium molybdenum alloy (CoCrMo) femoral head to evaluate the friction and wear performance of the new coated femoral head. Methods: Three groups were set up in the wear simulation experiment according to the type of femoral head. Group A: imported Cobalt-Chromium-Molybdenum alloy femoral head (CoCrMo); group B: Titanium alloy femoral head (Ti(6)Al(4)V) with carbon-based nano-multilayer coatings; group C: domestic Cobalt-Chromium-Molybdenum alloy femoral head (CoCrMo). All heads were jointed with an ultra-high molecular weight polyethylene (UHMWPE) acetabular cup. Serum samples were collected and stored in the hip joint simulator. After the sample has been digested and diluted, it was filtered through 5 μm, 1.2 μm and 0.4 μm filters, and the filter paper was collected for testing. Scanning electron microscope (SEM) was used to randomly select regions on the filter to obtain images of wear debris. Energy dispersive X-ray spectroscopy (EDS) was used to determine the elemental type of the particle and to eliminate possible contamination. The composition and structure of the abrasive chips were measured using Fourier transform infrared spectrometer (FTIR). The parameters related to the wear debris includingparticle size, shape, number and volume were calculated. The differences in correlation parameters between the groups were compared to evaluate the friction and wear properties of the new coated joints. Results: The main component of the wear debris produced was UHMWPE, and the particle size was mostly below 1 μm. The submicron particle ratio of group B was 49.4%, which was significantly lower than that of the group A and C (75% and 60%, respectively; χ(2)=66.032, 31.754, both P<0.017). The shape was mainly round, and there was no statistical difference between the groups (χ(2)=0.590, P=0.744). The number of particles in group B was significantly less than that of group C on all filters (t=9.960, 8.019, 5.790, all P<0.01), and less than group A on the 0.4 μm filter (t=7.810, P=0.000). Conclusion: The frictional wear performance of the new carbon-based nano-multilayer coatings femoral head is significantly better than that of the domestic femoral head, and even partially exceeds the imported femoral head level, which helps to reduce the production of particles and prevent osteolysis and aseptic loosening induced by UHMWPE particles.

[A systematic review of the economic burden of influenza in China]

Objectives: To understand the status of studies about influenza economic burden in mainland China and summarize their major results. Methods: The words of influenza, flu, cost, economic, burden, effectiveness, benefit, utility, China, and Chinese, were used as search keywords. Journal papers published during 2000-2018 were searched from Chinese electronic databases (CNKI and Wanfang) and English electronic databases (PubMed, Web of science, EconLit and Cochrane Library). The language of literature was restricted to Chinese and English. A total of 23 effective documents were included, and the descriptive characteristics, research indexes and methods included in the literature were analyzed. The monetary unit used in this review is Chinese Yuan (CNY). Results: The 23 study sites were mainly in the relatively developed and populous regions. The total cost per capita of laboratory-confirmed influenza,of all age-group was reported in 6 literatures, and only 4 literatures reported it in out-patients (range: 768.0-999.9 CNY), Only one study reported this indicator in inpatients (9 832.0 CNY). One literature reported the total cost per capita of influenza-like illness,, which was 205.1 CNY. And one literature reported that the direct medical cost of inpatients per capita in children under 5 years of age was 6 072.0 CNY while two literature reported this index for the elderly over 60 years of age, ranging from 14 250.0 to 19 349.1 CNY. Four articles reported the economic burden of influenza in urban and rural areas, one of which showed that the related expenses of urban influenza inpatients accounted for 31% of the average annual income, while which for the rural flow was 113%. Conclusion: The average economic burden of lab-confirmed influenza case is higher than that of influenza-like illness, and there are differences in outpatient indirect expenses and inpatients direct medical expenses. The direct medical burden for the hospitalized 60-years-and-beyond influenza case group is heavier thar other age group. By region, the influenza associated individual economic burden in rural area is higher than that of urban area..

P6495Role of vascular smooth muscles cells in naked mole rats during ageing (Heterocephalus glaber)

Vascular stiffening and a prothrombotic state consistently increase with age. We have shown previously that Vascular Smooth Muscle Cells (VSMCs) have a major role in both vascular stiffening and thrombin generation in the vascular wall in a context of hypertension (Arterioscler Thromb Vasc Biol 2015). Naked mole rats (NMRs) are the longest-lived rodent species, have a maximum lifespan exceeding 30 years, living approximately ten times longer than a similarly sized mouse, and do not develop arterial stiffening with age (AJP, 2014).

The objective was to analyze arterial composition as well as phenotypic VSMC changes from primary cultures in NMRs at 2- and 10-year old.

We used Thoracic aortas of young (2-year-old) and adult (10-year-old) NMRs for the study of arterial wall as well as for the preparation of VSMCs' primary cultures.

Our results showed no difference in elastin/collagen ratio and no intimal thickening in NMRs at 10-years-old compared to 2-years-old (n=4 in each group). Primary cultures showed positive alpha-actin staining without VSMC morphological changes up to 6 passages using standard conditions (20% fetal bovine serum). Smoothelin and myosin-heavy chain are similar at both ages. VSMCs density was identical in 2- and 10-years-old NMRs, whereas cell hypertrophy was observed in older animals.

Focal adhesions assessed by vinculin staining were unchanged between the two groups. There was no increase in plasma thrombin generation and at the surface of VSMCs up to 10 years of age associated with no increase in fibrinogen and factor VIII, both known to increase normally with age in humans.

Our findings showed an absence of canonical signs of normal vascular ageing in NMRs that are normally present in rodent and humans. The retaining of a VSMC phenotype and focal adhesion distribution support previous data observed in ageing. These results reinforce the current concept of VSMCs as emergent cells in the process of ageing.

[Analysis of 30 cases of inherited cardiac arrhythmia syndrome in children]

Objective: To analyze and summarize the diagnosis and treatment experience of common inherited cardiac arrhythmia syndrome in pediatric patients, and explore the most appropriate therapy. Methods: A retrospective review identified 30 pediatric cases (19 males, 11 females) diagnosed with long QT syndrome (LQTS), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), hypertrophic cardiomyopathy (HCM), arrhythmogenc right ventricular cardiomyopathy (ARVC) from January 2008 to December 2018 in the Pediatric Cardiology Department, Guangdong Provincial People's Hospital. Data obtained included the diagnosis, treatment and follow-up outcome. Results: The most common inherited cardiac arrhythmia syndromes were LQTS (n=14) including 1 case with epilepsy, CPVT (n=5), HCM (n=7), ARVC (n=1), and BrS (n=3). Twenty-seven cases were admitted to hospital due to syncope, whereas the remaining 3 cases of BrS had not presented with syncope before admission. The average onset age of inherited arrhythmia was (10.0±3.3) years. Genetic testing was performed on 20 patients. The median follow-up time was 40 months. Among 15 patients who underwent implantable cardioverter defibrillator (ICD) and survived, 2 patients had frequent ICD discharge. One patient underwent radiofrequency ablation, and the other one received left cardiac sympathetic denervation and an increased ICD defibrillation threshold, and the number of ICD discharge was significantly reduced. Among 10 patients who received drug therapy, 4 patients including two patients who discontinued treatment without advices died. Two patients whose parents refused treatment died, 1 case diagnosed with unexplained sudden cerebral death, and the remaining 2 cases without indication for drug therapy survived without any treatment. Conclusions: Mortality rate is high in pediatric patients with inherited cardiac arrhythmia and syncope. The therapeutic effect of drugs are not satisfactory, ICD implantation is the most effective treatment to prevent sudden cardiac death currently, but the postoperative frequent discharge should be brought to the forefront and handled in time.

[Study of mycelial polysaccharide from Paraisaria dubia of Ophiocordyceps gracilis asexual]

In order to provide a foundation for the development and application of Ophiocordyceps gracilis and increase the new resources of cordyceps,an asexual Paraisaria dubia was isolated from an O. gracilis fruit body. After 10 days of liquid fermentation,white globular mycelium and clear transparent fermentation were produced. The mycelium was extracted by hot water and precipitated with ethanol to obtain intracellular crude polysaccharide. The protein was deproteinized to obtain deproteinized polysaccharide. The intracellular pure polysaccharide was purified by Sepharose 4 B column chromatography and were analyzed by UV,IR,1 H-NMR,and13 CNMR data,as well as GC and HPLC. The results showed that the intracellular polysaccharide of P. dubia was composed of glucose,galactose and mannose with a molar ratio of 25. 54 ∶2 ∶1. It was a β-configuration glycosylic bond,containing pyranoside. The initial connection of polysaccharide was β(1→2)(1→4)(1→6) connection. This experiment provides a theoretical basis for the development and application of P. dubia.

[Interfacility transport with extracorporeal membrane oxygenation in pediatric patients: a multicenter study in China]

Objective: To investigate application and safety of pediatric interfacility-transport with extracorporeal membrane oxygenation (ECMO) in China. Methods: The data of 48 patients transported inter-hospital from February 2016 to May 2018 were collected from the following 4 centers: pediatric intensive care unit (PICU) of Bayi Children's Hospital Affiliated to the 7th Medical Center of PLA General Hospital, Pediatric Hospital of Fudan University, Henan Provincial People's Hospital and Children's Hospital of Zhejiang University School of Medicine. The data of patients' characteristics, ECMO mode and wean rate, and mortality were reviewed, which was further compared with the data of 57 compatible inner-hospital ECMO cases with t test, Rank sum test or chi-square test. Results: All the 48 interfacility-transports were accomplished by ambulance on land, with an average transfer distance of (435±422) km. The incidence of ECMO complications was 13% (6 case), without death. There were no significant differences in lactic acid, PaO(2) or SaO(2) before and after transport (4.0 (2.0, 7.5) vs. 3.0 (1.5, 6.0) mmol/L, Z=-1.579, P>0.05; 112(47, 405) vs. 166(122, 240) mmHg (1 mmHg=0.133 kPa), Z=-0.104, P>0.05; 0.97±0.02 vs. 0.96±0.03, t=1.570, P>0.05). Instead, PaCO(2) and pH were significantly different ((47±8) vs. (42±5) mmHg, t=2.687, P<0.05; 7.3±0.2 vs. 7.5±0.2, t=3.379, P<0.05). The total ECMO weaned rate was 73% (35/48) and the survival rate was 67% (32/48). No significant differences in demographic characteristics, ECMO mode or duration, transport distance or duration, or complications existed between the survival group and the death group (7/25 vs. 2/14, χ(2)=0.615, P>0.05; 4/28 vs. 2/14, χ(2)=0, P>0.05; (405±404) vs. (493±465) km, t=0.525, P>0.05; (5±4) vs. (5±5) h, t=0.388, P>0.05; 166 (128, 239) vs. 187(52, 405) h, Z=-0.104, P>0.05; 3/32 vs. 3/16, χ(2)=0.734, P>0.05). The lowest lactate value in survival group before ECMO transport was significantly lower than that in the death group ((5±5) vs. (8±6) mmol/L, t=2.151, P<0.05). There were neither significant differences in age, ECMO mode or support pattern (9/39 vs. 15/42, χ(2)=0.845, P>0.05; 6/42 vs. 7/50, χ(2)=0.001, P>0.05; 29/19 vs. 38/19, χ(2)=0.441, P>0.05), nor in ECMO weaned rate, survival rate or complications between interfacility-transport group and inner-hospital group (35/48 vs. 37/57, χ(2)=0.775, P>0.05; 32/48 vs. 35/57, χ(2)=0.313, P>0.05; 20/48 vs. 22/57, χ(2)=0.102, P>0.05). Conclusion: With appropriate transport equipment and mature teams who handle problems timely during the transport, critically ill children could be safely transported to the destination with ECMO.

Combination of LINE-1 hypomethylation and RASSF1A promoter hypermethylation in serum DNA is a non-invasion prognostic biomarker for early recurrence of hepatocellular carcinoma after curative resection

Hepatocarcinogenesis, a multistep process, involves not only genetic mutations but also epigenetic alterations. Widespread of global DNA hypomethylation is accompanied with specific regional hypermethylation especially at tumor suppressor genes' promoters. The aim of this study is to determine the efficacy of combined DNA methylation analysis of a global DNA methylation marker - LINE-1 and a tumor suppressor gene highly associated with the malignancy of HCC- RASSF1A in serum as a novel prognostic marker for diagnosis of early recurrence after curative resection.LINE-1 was hypomethylated in 66.7% (70/105) and RASSF1A promoter was hypermethylated in 73.3% (77/105) of HCC serum DNA samples by methylation specific PCR, but in none of the healthy controls: LINE-1 hypometylation (0/50) and RASSF1A hypermethylation (0/50). A significant association was found between LINE-1 hypomethylation and clinical pathologic features including HBsAg positivity (p=0.009), tumor size (p=0.001) and AFP levels (p<0.001). Besides, significant correlation was detected between RASSF1A promoter hypermethylation and lymph nodes metastasis (p=0.045).The results of Kaplan-Meier estimates of survival suggested that LINE-1 hypomethylation was highly associated with poor survival of patients (disease-free survival p=0.002, overall survival p=0.0123). More importantly, co-evaluation of LINE-1 hypomethylation and RASSF1A promoter hypermethylation was found to be significantly correlated to early recurrence and poor prognosis (disease-free survival p=0.0001, overall survival p=0.05) in patients after curative resection.In conclusion, our study showed that the combined examination of LINE-1 hypomethylation and RASSF1A promoter hypermethylation was effective in predicting early recurrence of HCC after curative resection. Patients with dual positivity of LINE-1 hypomethylation and RASSF1A promoter hypermethylation should be supplied with more intensive care and close follow-up after they undergo tumor resection.

[Application of nuclear magnetic dispersion weighted imaging and apparent diffusion coefficient in the identification of benign]

Objective:To determine the diagnostic role of diffusionweighted imaging(DWI) and apparent diffusion coefficient（ADC） under different b values in differentiating benign and malignant thyroid nodules by using postoperative histopathological results were taken as the reference standard. Method: From January 2017 to June 2018, 64 patients with thyroid nodules diagnosed by ultrasound in the head and neck surgery of Shanxi Cancer Hospital were collected, and a total of 80 nodules were collected. The Philips 3.0T superconducting magnetic resonance imaging system was used for T1 weighting, T2 weighting, and DWI horizontal axis scanning imaging. The b values were 300, 500, 800 and 1 000 s/mm², respectively. Taking postoperative histopathological results as the reference standard, the ADC values of thyroid nodules of all subjects were calculated and compared, and the working characteristics(ROC) curves of all subjects with b values were drawn, the area under the curve was calculated, and the threshold value of differentiating benign and malignant thyroid nodules was obtained. Result:A total of 80 nodules, 33 malignant and 43 benign were excluded, including 1 diffuse b-cell non-hodgkin's lymphoma, 2 parathyroid cysts, and 1 pure cystic patient. A total of 76 nodules were included. When b values were 300, 500, 800 and 1 000 s/mm², the average ADC values of malignant nodules were(1.498±0.210) ×10⁻³mm²/s, (1.311±0.190) ×10⁻³mm²/s, (1.134±0.170) ×10⁻³mm²/s, (0.972±0150) ×10⁻³mm²/s. The mean ADC values of benign nodules were(2.207±0.390) ×10⁻³mm²/s, (1.928±0.430) ×10⁻³mm²/s, (1.702±0.410) ×10⁻³mm²/s,(1.557±0.420) ×10⁻³mm²/s. At the same b value, the average ADC value of malignant nodules was lower than that of benign nodules, and the difference was statistically significant(t values were 9.279,7.641,7.301,7.569, P values were 0.000,0.000,0.000,0.000,0.000). The average ADC values of the benign and malignant nodules decreased with the increase of b value, and the difference was statistically significant(the F values of the benign and malignant groups were 210.091 and 353.822, respectively，P values are 0.000, 0.000). Under different b values, the area(AUC) of ROC curve is 0.927,0.884,0.878,0.901,and 95%CI are 0.862-0.993,0.804-0.956,0.794-0.962 and 0.829-0.972, respectively. When b value is 300 s/mm², AUC is the largest, indicating that it is the best indicator to distinguish benign and malignant thyroid nodules. The diagnostic threshold of benign and malignant nodules is 1.802×10⁻³mm²/s. Specificity, sensitivity, accuracy, positive predictive value, and negative predictive value were 95.00%,86.11%,90.79%,93.94% and 88.37%, respectively. Conclusion: DWI is a noninvasive diagnostic tool used to identify benign and malignant thyroid nodules. It can help to make a definite diagnosis before surgery and reduce the unnecessary burden of surgery.

[Etiology and clinical technology of the food impaction with tight proximal contacts]

Food impaction with tight proximal contacts, also known as kinetic food impaction and food impaction without anatomical structure destruction, is mainly caused by a transient separation in contacts area during mastication. It's an intractable food impaction with high morbidity and low cure rate. There are two kinds of pathogenesis accepted: the shifting of anterior teeth incongruous with adjacent teeth or lack of anterior shifting; lack of food escape grooves. The preferred treatment is occlusal adjustment, but it's difficult to determine the area and extent of selective grinding, to quantify the occlusal adjustment, or to predict the prognosis. This review summarized the pathogenesis and treatment modality for kinetic food impaction in order to provide evidence for future researches and clinical application.

Serum immunoinflammation-related protein complexes discriminate between inflammatory bowel disease and colorectal cancer

PURPOSE

Inflammatory bowel disease (IBD) is an important risk factor for colon cancer. Novel serum immunoinflammation-related protein complexes (IIRPCs) have shown associations with early cancer detection. Herein, we investigated the potential of serum IIRPCs for discriminating between IBD and colorectal cancer (CRC) patients.

METHODS

Serum protein complexes of 65 healthy controls, 57 CRC, 69 (ulcerative colitis) UC, and 67 (Crohn's disease) CD patients were isolated by native-PAGE. The gray values of serum IIRPCs bands in the gel were quantified using Quantity One software. The receiver-operating characteristic (ROC) curves were constructed to assess the discriminating ability by calculating the area under the ROC curve.

RESULTS

The serum IIRPCs levels in IBD and CRC patients were significantly elevated compared to healthy controls. ROC analysis indicated certain diagnostic ability of serum IIRPCs in differentiating IBD from CRC. Specifically, "a3" complex discriminated UC from CRC, with an AUC value of 0.722, sensitivity of 69.4% and specificity of 63.8%. Similarly, "b4" complex discriminated UC from CRC, with an AUC value of 0.709, sensitivity of 70.4%, and specificity of 60.0%. In addition, the "a3" complex also discriminated CD from CRC, with an AUC value of 0.785, sensitivity of 73.1%, and specificity of 74.1%, while the "b4" complex showed a tendency to discriminate CD from CRC, with an AUC value of 0.663, sensitivity of 67.9% and specificity of 50.0%. Thus, an equation based on multiple IIRPCs was built to further improve the discriminating power.

CONCLUSIONS

Serum IIRPCs can be used to discriminate IBD from CRC and may also be associated with early screening of colitis-associated cancer.

[Abnormal functional connectivity between sublaterodorsal nucleus and the motor cortex in Parkinson's disease with rapid-eye-movement sleep behavior disorder]

Objective: To investigate the abnormal functional connectivity between sublaterodorsal nucleus (SLD) and the brain motor areas in Parkinson's disease with or without rapid-eye-movement (REM) sleep behavior disorder by resting state functional magnetic resonance imaging (rfMRI). Methods: A total of 64 subjects recruited in the Department of Neurology, the People's Hospital of Zhengzhou University were enrolled in this study from August 2014 to December 2017 according to international diagnosis criteria, 20 cases with PD-RBD (PD-RBD group), 23 cases without PD-nRBD (PD-nRBD group) and 21 age, gender-matched healthy controls (HC group). All subjects were examined by Hoehn-Yahr, UPDRS-Ⅲ and rfMRI. Resluts: UPDRS-Ⅲ scores and Hoehn-Yahr staging were showed significantly different from that in the HC group(KW=-27.35, P<0.001) but showed no significantly difference from that in the PD-nRBD group(KW=6.01, P=0.807). Compared with the control group, the FC analysis showed reduced correlations from the left SLD to the right orbital middle frontal gyrus(T=-4.567 8, P<0.001), the left cingulate gyrus(T=-3.196 0,P<0.001), the left cerebellum(T=-4.267 0,P<0.001) and the right midbrain(T=-4.773 7, P<0.001), from the right SLD to the bilateral cerebellum (T(left)=-5.040 1, T(right)=-4.210 5, P<0.001), the left precuneus(T=-4.468 2,P<0.001) and the left precentral gyrus (T=-4.473 9,P<0.001) in the PD-RBD. The correlations between the left SLD and left cerebellum, right midbrain and between the right SLD and left precuneus, left precentral gyrus were negative correlated with the motor functional tests. Conclusions: There are abnormal functional connectivity from the SLD to the motor areas in PD-RBD patients, leading to clinical PD-RBD motor symptoms and movement disorders.

[Accuracy analysis of computer assisted navigation for condylectomy via intraoral approach]

OBJECTIVE

To explore the application accuracy of virtual preoperative plan after the condylectomy via intraoral approach under computer assisted surgical navigation, and to analyze the location and cause of the surgical deviation to provide reference for the surgical procedure improvement in the future.

METHODS

In the study, 23 cases with condylar hypertrophy (11 with condylar osteochondroma and 12 with condylar benign hypertrophy) in Department of Oral and Maxilloficial Surgery, Peking University School and Hospital of Atomatology from December 2012 to December 2016 were treated by condylectomy via intraoral approach under computer assisted surgical navigation. The patient's spiral CT data were imported into ProPlan software before operation, and the affected mandibular ramus was reconstructed three-dimensionally. The condylar osteotomy line was designed according to the lesion range, and the preoperative design model was generated and introduced into the BrainLab navigation system. Under the guidance of computer navigation, the intraoral approach was used to complete the condylar resection according to the preoperative design of the osteotomy line. Cranial spiral CT of the craniofacial region was taken within one week after operation. three-dimensional reconstruction of the mandibular ramus at the condylectomy side was performed, and the condylar section was divided into six segments (anterolateral, anterior, anteromedial, posteromedial, posterior, and posterolateral) and the corresponding regional measurement points P1 to P6 were defined. Then the preoperative virtual model and the postoperative actual model were matched by Geomagic studio 12.0 to compare the differences and to analyze the accuracy of the operation.

RESULTS

All the patients had successfully accomplished the operation and obtained satisfactory results. Postoperative CT showed that the condyle lesion was completely resected, and the condylar osteotomy line was basically consistent with the surgical design. No tumor recurrence or temporomandibular joint ankylosis during the follow-up period. The postoperative accuracy analysis of the condylar resection showed that the confidence intervals measured by the six groups of P1 to P6 were (-2.26 mm, -1.89 mm), (-2.30 mm, -1.45 mm), (-3.37 mm, -2.91 mm), (-2.83 mm, -1.75 mm), (-1.13 mm, 0.99 mm), and(-1.17 mm, 0.17 mm), where P3 group was different from the other 5 groups. There was no significant difference between the P5 and P6 groups and the difference between the other four groups was statistically significant.

CONCLUSION

Under the guidance of computer navigation, the intraoral approach can be performed more accurately. The surgical deviation of each part of the osteotomy surface is mainly due to excessive resection. The anterior medial area of the anterior medial condyle represents the most excessive resection. The posterior and posterior lateral measurement points represent the posterior condylar area. The average deviation is not large, but the fluctuation of the deviation value is larger than that of the other four groups. The accuracy of computer-assisted subtotal resection has yet to be improved.

[Impact on the intestinal microbiota of early antibiotic treatment in preterm neonates]

Objective: To investigate the impact of early antibiotics treatment on intestinal microbiota in preterm infants. Methods: The cohort study was performed from January 2015 to June 2015 in Neonatal Intensive Care Unit of Peking University Third Hospital. A total of 33 preterm infants were enrolled, among whom 25 were antibiotics-exposure group, and 8 were non-exposure group. Serial stool samples were collected on the first day, 14th and 30th days of life and analyzed by high-throughput sequencing. In exposure group, intestinal microbiota was also analyzed at 8 months to 1 year of age. Categorical variables were analyzed with χ(2) test, and continuous variables were analyzed with t test or non-parametric test. Results:Proteobacteria was the most prominent flora after birth in all cases (exposure group 69.6%, non-exposure group 83.7%) . In exposure group, at the phylum level, Proteobacteria was the dominant bacteria within the first 30 days, followed by Firmicutes after 30 days of life. At the genus level, Escherichia was the most abundant genera within 30 days after birth, while Veillonella became dominant after 8 months to 1 year of life. In non-exposure group, at the phylum level, Proteobacteria was the dominant phylum within the first 30 days. At the genus level, Actinobacteria (37.5%) was the dominant genus after birth, followed by Escherichia within the first month. Intestinal bacterial abundance and diversity were lower in exposure group, which was most significant on 30th day of life (shannon index 2.6 vs.3.4, ACE index 563.9 vs.591.6) . The influence of single antibiotics was less significant than combined treatment (shannon index 2.7 vs.2.5, ACE index 727.3 vs.492.9) . At the genus level, compared to non-exposure group, there were significant decrease of Escherichia (9.3% vs. 54.3%, Z=-2.830, P=0.005), Klebsiella (0.03% vs.12.4%,Z=-2.240, P=0.025), and Clostridium (0.2% vs. 4.8%, Z=-2.979, P=0.003) in exposure group on 14 days of life. Bifidobacterium (0.1% vs.2.0%, Z=-2.349, P=0.019) in cases treated with combined antibiotics was lower than that treated with antibiotic monotherapy on 30 days of life. Conclusions: Early application of combined antibiotics impacts on the intestinal microbiome of preterm infants significantly. The infants who have received antibiotic after birth have lower quantity and diversity of Clostridium, Lactobacillus, Bacteroides and Bifidobacterium.

Homogeneous (Cu, Ni)6Sn5 intermetallic compound joints rapidly formed in asymmetrical Ni/Sn/Cu system using ultrasound-induced transient liquid phase soldering process

Homogeneous (Cu, Ni)₆Sn₅ intermetallic compound (IMC) joints were rapidly formed in asymmetrical Ni/Sn/Cu system by an ultrasound-induced transient liquid phase (TLP) soldering process. In the traditional TLP soldering process, the intermetallic joints formed in Ni/Sn/Cu system consisted of major (Cu, Ni)₆Sn₅ and minor Cu₃Sn IMCs, and the grain morphology of (Cu, Ni)₆Sn₅ IMCs subsequently exhibited fine rounded, needlelike and coarse rounded shapes from the Ni side to the Cu side, which was highly in accordance with the Ni concentration gradient across the joints. However, in the ultrasound-induced TLP soldering process, the intermetallic joints formed in Ni/Sn/Cu system only consisted of the (Cu, Ni)₆Sn₅ IMCs which exhibited an uniform grain morphology of rounded shape with a remarkably narrowed Ni concentration gradient. The ultrasound-induced homogeneous intermetallic joints exhibited higher shear strength (61.6 MPa) than the traditional heterogeneous intermetallic joints (49.8 MPa).

Prognostic significance of downregulated BMAL1 and upregulated Ki-67 proteins in nasopharyngeal carcinoma

This study assessed the prognostic value of BMAL1 and Ki-67 expression in patients with nasopharyngeal carcinoma. Level of BMAL1 mRNA was assessed in tissue specimens from 36 nasopharyngeal carcinomas and 20 nasopharyngeal chronic inflammations using quantitative reverse transcriptase-polymerase chain reaction. Expression of BMAL1 and Ki-67 proteins was analyzed immunohistochemically in 90 paired nasopharyngeal carcinoma and distant normal tissues. The Kaplan-Meier curves and the Log-rank test were used to calculate prognostic significance stratified by BMAL1 and Ki67 protein expression and the COX regression model was to analyze the multivariate prognosis. BMAL1 mRNA was significantly reduced in nasopharyngeal carcinoma (4.67 ± 0.27 versus 6.64 ± 0.51 in chronic inflammation tissues, p = 0.002). Level of BMAL1 mRNA was associated with tumor distant metastasis (3.37 ± 0.66 versus 5.04 ± 0.27 compared with non-metastasis, p = 0.011). Level of BMAL1 protein was also reduced in tumor tissues and BMAL1 expression was associated with better 1-, 3- and 5-year overall survival (OS) of cancer patients (92.6%, 69.2% and 62.3% versus 59.1%, 40.9% and 0% in patients with low BMAL1 expressed tumors; p = 0.000). BMAL1 expression and age were independent prognostic factors for OS (p = 0.032). Furthermore, Ki-67 expression was high in tumor versus normal tissues and associated with poor OS of cancer patients (p = 0.035). The Pearson correlation analysis showed that there was an inverse association between BMAL1 and Ki-67 protein expression (p = 0.021). This study demonstrated that lost BMAL1 and Ki-67 overexpression were associated with poor OS of nasopharyngeal carcinoma patients.

[Evaluation of accuracy of virtual occlusal definition in Angle class I molar relationship]

OBJECTIVE

To evaluate the accuracy of virtual occlusal definition in non-Angle class I molar relationship, and to evaluate the clinical feasibility.

METHODS

Twenty pairs of models of orthognathic patients were included in this study. The inclusion criteria were: (1) finished with pre-surgical orthodontic treatment and (2) stable final occlusion. The exclusion criteria were: (1) existence of distorted teeth, (2) needs for segmentation, (3) defect of dentition except for orthodontic extraction ones, and (4) existence of tooth space. The tooth-extracted test group included 10 models with two premolars extracted during preoperative orthodontic treatment. Their molar relationships were not Angle class I relationship. The non-tooth-extracted test group included another 10 models without teeth extracted, therefore their molar relationships were Angle class I. To define the final occlusion in virtual environment, two steps were included: (1) The morphology data of upper and lower dentition were digitalized by surface scanner (Smart Optics/Activity 102; Model-Tray GmbH, Hamburg, Germany); (2) the virtual relationships were defined using 3Shape software. The control standard of final occlusion was manually defined using gypsum models and then digitalized by surface scanner. The final occlusion of test group and control standard were overlapped according to lower dentition morphology. Errors were evaluated by calculating the distance between the corresponding reference points of testing group and control standard locations.

RESULTS

The overall errors for upper dentition between test group and control standard location were (0.51±0.18) mm in non-tooth-extracted test group and (0.60±0.36) mm in tooth-extracted test group. The errors were significantly different between these two test groups (P<0.05). However, in both test groups, the errors of each tooth in a single dentition does not differ from one another. There was no significant difference between errors in tooth-extracted test group and 1 mm (P>0.05); and the accuracy of non-tooth-extracted group was significantly smaller than 1 mm (P<0.05).

CONCLUSION

The error of virtual occlusal definition of none class I molar relationship is higher than that of class I relationship, with an accuracy of 1 mm. However, its accuracy is still feasible for clinical application.

Construction of a ptfA chitosan nanoparticle DNA vaccine against Pasteurella multocida and the immune response in chickens

The aim of this study was to evaluate the effect of chitosanon the immune response induced by a DNA vaccine based on the ptfA gene of avian Pasteurella multocida. Naked DNA vaccine was packed with chitosanmolecules, resulting in a chitosannanoparticle DNA vaccine. The encapsulation efficiency, shape, size and resistance to DNA degradation were determined. The vaccine was administered to chickens and serum antibody, interferon-γ (IFN-γ), interleukin-2 (IL-2) and interleukin-4 (IL-4) concentrations were determined and lymphocyte proliferation assays were performed. After challenge with virulent avian P. multocida, protective efficacy was evaluated. The encapsulation efficiency of the chitosan nanoparticle DNA vaccine was 95.3%. The particle size was approximately 200nm and close to spherical in shape and it could effectively resist degradation by DNases. Following vaccination, serum antibodies, stimulation index (SI) value and concentrations of IFN-γ and IL-2 in chickens vaccinated with the chitosan nanoparticle DNA vaccine were significantly higher than those that were vaccinated with the naked DNA vaccine (P-values are 0.026, 0.045, 0.039 and 0.024, respectively). However, the concentrations of IL-4 in the two DNA vaccines group were no significant difference (P=0.157). The protective efficacy rate provided by naked DNA vaccine, chitosan nanoparticle DNA vaccine and the attenuated live vaccine were 56%, 68% and 88%, respectively. The results indicated that chitosan was able to enhance the immune response to a naked DNA vaccine based on the ptfA gene of P. multocida.

[Comparision of risk factors and pathogens in patients with early- and late-onset ventilator-associated pneumonia in intensive care unit]

Objective: To compare risk factors and bacterial etiology in patients with early-onset versus late-onset ventilator-associated pneumonia (VAP) in intensive care unit (ICU). Methods: This prospective cohort study enrolled mechanically ventilated patients hospitalized for more than 48 hours in the first affiliated hospital, China Medical University from Jan 2012 to Jun 2016. Subjects were classified by ventilator status: early-onset VAP (< 5 d ventilation, E-VAP) or late-onset VAP (≥ 5 d ventilation, L-VAP). Potential risk factors and pathogen were evaluated. Results: A total of 4 179 patients in adult ICU were screened, 3 989 (95.5%) of whom were mechanically ventilated, 962 patients with mechanical ventilation time ≥ 48 h. VAP developed in 142 patients. E-VAP and L-VAP had different potential risk factors based on statistical analysis.Independent risk factors for E-VAP included male (OR=1.825, 95%CI 1.006-3.310), chronic obstructive pulmonary disease (COPD; OR=3.746, 95%CI 1.795-7.818), emergency intubation (OR=1.932, 95%CI 1.139-3.276), aspiration (OR=3.324, 95%CI 1.359-8.130). Whereas independent risk factors for L-VAP were coma (OR=2.335, 95%CI 1.300-4.194), renal dysfunction (OR=0.524, 95%CI 0.290-0.947), emergency intubation (OR=2.184, 95%CI 1.334-3.574). Mortality in E-VAP and L-VAP group were both higher than the non-VAP group[30.2%(19/63)vs 19.8%(162/820), P=0.044; 29.1%(23/79) vs 19.8%(162/820), P=0.046]. The pathogens isolated from early-onset versus late-onset VAP were not significantly different between groups, which the most common ones were acinetobacter baumannii, pseudomonas aeruginosa and klebsiella pneumoniae. Conclusion: E-VAP and L-VAP have different risk factors, however related pathogens are similar. Different specific preventive strategies are suggested based on different onset of VAP.

Rapid formation of Ni3Sn4 joints for die attachment of SiC-based high temperature power devices using ultrasound-induced transient liquid phase bonding process

High melting point Ni₃Sn₄ joints for the die attachment of SiC-based high temperature power devices was successfully achieved using an ultrasound-induced transient liquid phase (TLP) bonding process within a remarkably short bonding time of 8s. The formed intermetallic joints, which are completely composed of the refined equiaxial Ni₃Sn₄ grains with the average diameter of 2μm, perform the average shear strength of 26.7MPa. The sonochemical effects of ultrasonic waves dominate the mechanism and kinetics of the rapid formation of Ni₃Sn₄ joints.

[The diagnostic value of plasma fibrin related markers in perioperation of femoral fracture]

Objective: To investigate potential value of fibrin related markers in patients with femoral fracture during perioperative period. Methods: Ninety-five patients were enrolled, including 39 males with (53±24) years old and 56 females with (73±13) years old, of which 44 fracture on caput femoris, 34 collum femoris and 17 shaft of femur. Sampling on the day before operation and 1(st,) 3(rd,) 5(th) days after operation, fibrin monomer (FM), D-dimer(DD), fibrinogen degradation product (FDP) and other coagulation assays were detected by reagents from Stago. Difference in day-to-day and between surgical sites were analyzed with general linear model (repeated measures). Results: FDP level on pre-operation, 1(st,) 3(rd,) 5(th) day after operation were 7.88(5.19, 12.12), 15.68(9.84, 29.48), 8.44 (6.27, 12.49) and 10.28 (7.56, 14.00) mg/L, the value of fibrin monomer were 5.00 (5.00, 6.03), 9.89(5.04, 30.12), 5.00 (5.00, 6.04) and 5.02(5.00, 5.76) mg/L. The value of D-Dimer were 2.24(1.41, 3.60), 4.78(2.74, 9.18), 2.60(1.79, 3.88) and 2.91(2.20, 3.85) mg/L, respectively, each parameter changs statistically during observation (Z=4.758, 6.027, 3.238 respectively, P<0.05). On the 5th day after surgery, fibrin monomer in patients with venous thrombus embolism (VTE) were higher than that in patients without VTE, 10.18(7.24, 28.11) mg/L vs 5.10(5.00, 6.73) mg/L (Z=-1.580, P<0.05), which showed potential value evaluating of post-operative VTE. No statistical changes were found in prothrombin time or thrombin time (TT) (P>0.05), but activated partial thromboplastin time (APTT) varied from day to day in (38.1±4.9), (40.8±5.2), (45.1±6.2) and (41.9±6.3)s with statistically difference (F=7.127, P<0.05). Similarly, fibrinogen changed statistically in (5.01±0.94), (4.99±1.35), (6.00±1.75), (5.81±1.38)g/L (F=8.927, P<0.05). Conclusion: Fibrin monomer, additional to markers as D-dimer, shows its value on activated coagulation associated to post-operative thromboembolism for patients receiving femoral surgery.

[Ventilator-associated pneumonia among premature infants <34 weeks' gestational age in neonatal intensive care unit in China: a multicenter study]

Objective: To investigate the incidence and pathogen distribution of ventilator-associated pneumonia (VAP) among preterm infants admitted to level Ⅲ neonatal intensive care units (NICU) in China. Method: A prospective study was conducted in 25 level Ⅲ NICU, enrolling all preterm infants <34 weeks gestational age admitted to the participating NICU within the first 7 days of life from May 2015 to April 2016. Chi-square test, t test and Mann-Whitney U test were used for statistical analysis. Result: A total of 7 918 patients were enrolled, within whom 4 623(58.4%) were males. The birth weight was (1 639±415) g and the gestational age was (31.4±2.0) weeks; 4 654(58.8%) infants required non-invasive mechanical ventilation and 2 154(27.2%) required intubation. Of all the mechanically ventilated patients, VAP occurred in 95 patients. The overall VAP rate was 7.0 episodes per 1 000 ventilator days, varying from 0 to 34.4 episodes per 1 000 ventilator days in different centers. The incidence of VAP was 9.6 and 6.0 per 1 000 ventilator days in children's hospitals and maternity-infant hospitals respectively, without significant differences (t=1.002, P=0.327). Gram-negative bacilli (76 strains, 91.6%) were the primary VAP microorganisms, mainly Acinetobacter baumannii (24 strains, 28.9%), Klebsiella pneumonia (23 strains, 27.7%), and Pseudomonas aeruginosa (10 strains, 12.0%). Conclusion: The incidence of VAP in China is similar to that in developed counties, with substantial variability in different NICU settings. More efforts are needed to monitor and evaluate the preventable factors associated with VAP and conduct interventions that could effectively reduce the occurrence of VAP.

Ionizing Radiation Impairs Endogenous Regeneration of Infarcted Heart: An In Vivo 18F-FDG PET/CT and 99mTc-Tetrofosmin SPECT/CT Study in Mice

Epidemiological studies have suggested that ionizing radiation increases cardiovascular disease risk, but the relevant mechanism is poorly understood. We recently demonstrated that adult mice exposed to whole-body irradiation with 3 Gy gamma rays significantly decreases the number and quality of cardiac stem cells. To further determine if radiation impairs myocardial regenerative potency, a myocardial infarction model was established in adult C57BL/6 mice by ligating the left anterior descending artery approximately 6 h after sham- or whole-body gamma irradiation (0 or 3 Gy). To evaluate the regenerative potency of the infarcted heart, we measured the myocardial perfusion and remodeling by ¹⁸F-FDG PET/CT and ^99mTc-tetrofosmin SPECT/CT at 1-2 days (baseline) and 14-15 days (end point) after infarction, respectively. Mice were sacrificed at day 15 after infarction, and heart tissue was collected for histological analysis. The infarct area of the left ventricle was significantly larger in irradiated mice than healthy controls 14 days after infarction, although it was similar between the groups at the baseline. However, histological analysis showed that the infarct size and left ventricle wall thickness were not significantly different among the groups. Compared to the healthy controls, irradiated mice had significantly less c-kit-positive stem cells, less Sca-1-positive stem cells, less proliferating cells, more apoptotic cells and lower vessel density within the infarcted heart. The results of this study suggest that whole-body irradiation with 3 Gy gamma rays impairs the endogenous regeneration of infarcted heart, which may indirectly predict future cardiovascular disease risk.