Objective To explore the clinical and imaging factors influencing the patients' prognosis after preoperative radiotherapy for local advanced rectal cancer.Methods We retrospectively analyzed 106 locally advanced rectal cancer patients from June 2004 to September 2015 in our institution.All patients underwent preoperative radiotherapy.According to the Mandard score,patients were divided into 5 groups (TRG1-5).All patients were divided into two groups according to the TRG,which including good responder (TRG1 + 2) and poor responder (TRG3 + 4 + 5) groups.All of the tumor ADC values of post-RT were measured by Diffusion-weighted MRI technology,and the relationship between tumor ADC values of post-RT and TRG was analyzed.Results In univariate analysis,age,chemotherapy,pT,pN,differentiation degree,vascular invasion and TRG were significantly associated with overall survival (x2 =3.945-8.110,P ＜ 0.05).Multivariate analysis indicated that differentiation degree and TRG were the independent prognostic factors for OS (x2 =5.221,6.563,P ＜ 0.05).No significant difference was found between long-course and short-course radiotherapy group (P ＞ 0.05) in OS.The good responder group had a favorable survival in 5-year OS compared to the poor responder group (x2 =8.110,P ＜ 0.05).Preoperative radiotherapy,preoperative chemotherapy,pathological type,differentiation degree and gross type,vascular tumor thrombus and tumor ADC values of post-RT were significantly associated with TRG (x2 =4.189-18.139,P ＜ 0.05).The best critical point of tumor ADC values of post-RT was 1.7 x 10-3 mm2/s by using ROC curve.The accuracy of tumor ADC values of post-RT in predicting TRG1 + 2 was 70％.Conclusions The TRG can predict the efficacy of preoperative radiotherapy in patients with locally advanced rectal cancer based on the Mandard score.There was no significant difference in OS between long-course radiotherapy group and short-course radiotherapy group.The tumor ADC values of post-RT might become a potential factor to predict TRG in patients with locally advanced rectal cancer after preoperative radiotherapy.

Objective:To investigate the etiology of pleural effusion in hospitalized children in Beijing Children′s Hospital.Methods:Clinical information of children with pleural effusion admitted to Beijing Children′s Hospital Affiliated to Capital Medical University from January 2016 to December 2018 was retrospectively analyzed.According to the etiology, the children were divided into infection group (parapneumonic pleural effusion, tuberculous pleurisy and empyema) and non infection group.According to the age, the children were further divided into ≤ 3 years old, >3-7 years old and > 7 years old groups.Classification of statistics was performed, and the etiology of pleural effusion were retrospectively analyzed.Results:Among the 1 165 children with pleural effusion, 746 cases(64.0%) were infected with pleural effusion, 697 cases (697/746, 93.4%) of who were parapneumonic effusion.In patients with parapneumonic effusion, 457 cases (61.3%) had Mycoplasma pneumonia (MP) infection.Infectious pleural effusion was more common in children >7 years old(339/479 cases, 70.8%), while non-infectious pleural effusion was prevalent in children under 3 years old(188/324 cases, 58.0%). The difference was statistically significant ( χ2=96.33, P<0.05). Among the patients with non-infectious pleural effusion, 239 cases (239/419 cases, 57.0%) had multi-system diseases and 97 cases (97/419 cases, 23.2%) had malignant pleural effusion.All the 18 deaths were non-infectious pleural effusion. Conclusions:The leading reason for pleural effusion in children is infection.The most prevalent symptom is parapneumonic effusion, which is mainly caused by MP.

Objective:To investigate epidemiological characteristics and macrolide-resistance of hospitalized children with Mycoplasma pneumoniae (MP) infections in Beijing from 2016 to 2019, so as to provide basis for the prevention and treatment of pediatric Mycoplasma pneumoniae pneumonia (MPP).Methods:The clinical data were analyzed retrospectively from 8 691 children hospitalized with community acquired pneumonia in Beijing Children′s Hospital between January 2016 and September 2019.MP RNA was detected by simultaneous amplification and testing (SAT), and macrolide resistance of MP was examined by MP and macrolide-resistant isolate diagnostic kit (PCR with fluorescence probes). Chi- square test was used for categorical analysis. Results:Among 8 691 cases detected by SAT, the overall detection rate of MP was 28.10% (2 442/8 691 cases). The detection rates of MP from 2016 to 2019 were 26.23%, 31.36%, 27.84 % and 26.57%, respectively.The detection rate of MP in 2017 was significantly higher than that in other years ( χ2=16.11, P<0.05). The detection rate of MP in females was 29.65%(1 107/3 733 cases), which was evidently higher than that in males 26.93%(1 335/4 958 cases) ( χ2=7.85, P<0.05). The positive rates of MP in summer[32.21% (726/2 254 cases)] and autumn[39.76%(852/2 143 cases)] were significantly higher than those in spring[17.00% (327/1 924 cases)] and winter[22.66%(537/2 370 cases)] ( χ2=315.15, P<0.001). The percentages of MP were 35.06%(732/2 088 cases) in preschoolers and 37.71%(1 160/3 076 cases) in school-age children, which were significantly higher than 11.20%(232/2 072 cases) in infants and 22.01% (318/1 445 cases) in toddlers ( χ2=509.89, P<0.001). Macrolide resistance detection was conducted in 1 524 patients by fluorescent PCR.Among them, 1 386 patients were positive for drug resistance, and the positive rate was 90.94%.The prevalence of macrolide-resistant MP from 2016 to 2019 were 88.19%, 90.93%, 90.56% and 92.90%, respectively.Macrolide-resistant rates were not related with gender, age and season. Conclusions:MP can be detected in all seasons, but most prevalently in summer and autumn.Girls are more prone to MP infections than boys.The detection rate of MP increases with age, and the positive rate is higher in preschoolers and school-age children.During the 4-year study period, the drug resistant rate of MP remain high.