Objective To analyze the clinical features and common etiology of lung nodules in children. Methods The etiology, diagnosis, radiological features from 98 hospitalized children of lung nodules were analyzed. Results Of them, 58 were male and 40 were female aged from 0.2 years old to 14.8 years old. Pulmonary infection were found in 41 cases (41.8%) including tuberculosis in 15 cases (15.3%), pulmonary fungal infection in 13 cases (13.3%), pneumonia in 11 cases (11.2%), lung trematode in 2 cases (2.0%). Pulmonary metastases were found in 28 cases (28.6%), multiple pulmonary arteriovenous fistula in 1 case (1.0%), and pulmonary contusion in 1 case (1.0%) and unknown etiology in 27 cases (27.6%). Conclusions The etiology of lung nodules is complicated, in which infectious diseases are the most commonly seen, followed by pulmonary metastases. Biopsy is the golden standard of diagnosis.

Bronchopulmonary dysplasia(BPD)is the most common chronic respiratory disease in premature in-fants,there is a lack of effective treatment now. In recent years,animal studies showed that treatment of mesenchymal stem cells (MSCs)can ameliorate hyperoxia-induced lung injury by promoting the restoration of alveolar epithelium and reducing the inflammation of lung through regeneration,paracrine and immunomodulatory,moreover,there has been a clinical trial shows that MSCs in the treatment of BPD is safe and feasible. Which may benefit the recovery of BPD and bring a hope for radical treatment of BPD. Now,focusing on the biological characteristics of MSCs,the mechanism and application of MSCs in the treatment of BPD in animal models and clinical trials as well as the existing problems in the latest research were reviewed.

Refractory pulmonary disease is a respiratory disease that seriously threatens the health of patients, and can lead to impaired pulmonary function and even respiratory failure.Currently, conventional drug therapy does not work well, so it is particularly important to find more effective treatments.Mesenchymal stem cells(MSCs) are a kind of multifunctional stem cells, which can promote the repair of damaged cells by regulating inflammatory and immune reactions and boost the regeneration of damaged tissues through paracrine.Therefore, MSCs are expected to provide a possibility for the treatment of refractory lung pulmonary diseases.

We describe a case of fetal sacrococcygeal teratoma detected by ultrasound at 14 gestational weeks. The tumor was classified as "type Ⅰ" by ultrasonography combined with MRI. The cystic part accounted for over 60% of the mass before 26 weeks and ruptured spontaneously at 28 weeks. The size of the tumor was 12.8 cm×9.7 cm×12.3 cm at 36 +5 gestational weeks. A female newborn was born through cesarean section at 37 weeks of gestation and had the tumor removed surgically on the postnatal day 4. Postoperative follow-up showed that the neonate had a good prognosis without physiological dysfunction.

Objective:Patients are breathing freely during adjuvant proton pencil beam radiotherapy after breast conserving surgery. Fluctuation of the thorax may affect the position of the end of the proton beam flow, which needs to be precisely evaluated on a millimeter scale.Methods:For 20 patients with breast cancer treated with proton radiotherapy after breast conserving surgery, PET-CT scan was performed approximately 10 min after the end of proton radiotherapy. The images of PET-CT were processed for ROI determination and sampling line (profile) extraction on a Raystation RV workstation to calculate the actual difference between the predicted and real radioactivity from the same spatial location as obtained by PET acquisition R50. Then, the differences in the spatial location between the actual process of proton irradiation and the planned process were obtained. Depth difference values for each pair of sampling lines were presented. Results:For 20 patients with breast cancer with a median follow-up of 22 months (range 12 - 46 months), all patients survived at the last follow-up, and no radiation pneumonitis was observed during the follow-up period. Among the verification results of 21 cases, the depth difference of evenly distributed was (-0.75±1.89) mm in the primary field and (-0.82±2.06) mm in the secondary field; The depth difference of sequential treatment was (1.81±1.87) mm in the primary field and (1.32±1.74) mm in the secondary field; The depth difference of synchronous addition in the primary field was (-1.47±1.44) mm, and the depth difference in the secondary field was (-1.48±2.11) mm.Conclusion:The results of off-line PET-CT in vivo biological verification show that the accuracy of the dose boundary cut-off was within 3 mm in breast cancer patients, which meets the clinical and physician requirement for the precision in breast cancer treatment.