Objective: To analyze the spatial temporal distribution characteristics of tuberculosis among high school students at county levels in Gansu Province from 2018 to 2022,so as to provide a scientific basis for tuberculosis prevention and control in schools. Methods: Tuberculosis data from high school students in counties (districts) reported in Gansu Province from 2018 to 2022 was collected from the Tuberculosis Information Management System and Infectious Disease Information Reporting System of the Chinese Disease Prevention and Control Information Management System. Demographic data of high school students in counties (districts) came from the General Management System of the Chinese Disease Prevention and Control Information Management System, and the spatial clustering of the reported incidence rate of pulmonary tuberculosis among high school students in Gansu Province in the past five years was analyzed using the methods of global spatial autocorrelation (Moran s I) and local indicators of spatial audocorrelation(LISA). Results: A total of 41 885 pulmonary tuberculosis cases were reported in various counties of Gansu Province From 2018 to 2022, with an average reported incidence rate of 32.81/100 000. During the same period, 1 170 high school students cases were reported, with an average reported incidence rate of 13.72/100 000. With the exception of 2020, the reported incidence rate of pulmonary tuberculosis among high school students was non random distribution in other 4 years, showed a moderate intensity of spatial clustering. From 2018 to 2022, most counties in Gansu Province reported that the incidence rate of pulmonary tuberculosis among high school students was 10.00/100 000 or below, the counties with reported incidence rate >40.00/100 000 were mainly distributed in Luqu County, Maqu County, Diebu County, Hezuo City, Xiahe County of Gannan Prefecture, Gangu County and Wushan County of Tianshui Prefecture, Wenxian County and Kangxian County of Longnan Prefecture, Huachi County of Pingliang Prefecture, Huanxian County of Qingyang Prefecture. The number of counties where the reported incidence rate of tuberculosis among high school students more than 30.00/100 000 gradually decreased from 2018 to 2022. In the past five years, the reported incidence rate of tuberculosis among high school students in all counties of Gannan Prefecture remained above 40.00/ 100 000 . The LISA analysis results showed that the high incidence areas were mainly concentrated in Gannan Prefecture. Conclusions The epidemic situation of pulmonary tuberculosis among high school students in Gansu province from 2018 to 2022 is still a serious condition, showing the characteristics of unbalanced regional distribution. The reported incidence rate shows a strong spatial clustering, and the hot spots are concentrated in the counties (districts) of Gannan prefecture in Gansu Province.

Objective:To investigate mucosal injury after high-dose methotrexate (HD-MTX) chemotherapy in treatment of children with acute lymphoblastic leukemia (ALL), and to analyze the association with methotrexate blood concentration, risk stratification and clinical efficacy.Methods:The data of 95 children with ALL who received 539 times of HD-MTX chemotherapy in the First Hospital of Harbin from November 2015 to October 2018 were retrospectively analyzed, and the association of mucosal injury with methotrexate blood concentration, disease risk degree and clinical efficacy was also analyzed.Results:Among 95 children who received 539 times of HD-MTX chemotherapy, the total incidence of mucosal injury was 8.4% (45/539); the incidence of mucosal injury was 4.6% (11/239), 7.6% (8/105), 13.3% (26/195), respectively in the low-risk group, middle-risk group and high-risk group. With the elevation of disease risk, the incidence of mucosal injury was increased ( χ2 = 10.787, P < 0.05). There was no correlation of the degree of mucosal injury with methotrexate blood concentration and disease risk degree (all P > 0.05), and the mucosal injury was not related with the clinical efficacy ( P > 0.05). Conclusion:After the application of HD-MTX in children with ALL, adjustment of the dose of rescue drug by monitoring of methotrexate blood concentration can improve the safety of therapeutic drugs.

Objective:To explore the therapeutic effect of low-dose arsenous acid/tretinoin with or without low-dose cytarabine induction regimen on myelodysplastic syndromes (MDS) with TET2 gene mutation in children.Methods:Nine children with MDS who were hospitalized at the First Hospital of Harbin from March 2009 to April 2018 were collected, including 3 cases of refractory cytopenia of childhood (RCC), 4 cases of MDS with excess of blasts type Ⅰ (MDS-EBⅠ) and 2 cases of MDS with excess of blasts type Ⅱ (MDS-EBⅡ). The next-generation gene sequencing method (NGS) was applied to detect the TET2 gene mutation in bone marrow cells of children with MDS. The low-dose arsenous acid/tretinoin with or without low-dose cytarabine induction regimen was adopted to conduct tiered therapy on children with MDS. The clinical efficacy was assessed in line with the MDS response evaluation criteria adopted by the MDS International Working Group (IWG) in 2006.Results:Among the 9 patients, the short-term clinical efficacy was observed in 8 cases. Two patients with TET2 gene mutation achieved the short-term clinical efficacy of bone marrow complete remission (mCR) and hematological improvement (HI). Among 7 patients without TET2 gene mutation, 4 patients obtained CR, 1 patients obtained mCR and HI, and 1 patients obtained stable disease (SD) in terms of the short-term clinical efficacy.Conclusion:The low-dose arsenous acid/tretinoin with or without low-dose cytarabine regimen may be beneficial to MDS children with TET2 gene mutation.

Objective:To summarize the preliminary clinical experience of utilizing ureteral balloon dilation catheter in the treatment of "difficult ureter" during ureteroscopic lithotripsy, and to discuss the efficacy and safety of the technique.Methods:Clinical data of 28 patients (30 sides) with upper urinary tract calculi admitted to Beijing Tsinghua Changgung Hospital Affiliated to Tsinghua University from April 2021 to July 2022 were retrospectively analyzed. There were 23 males (82.1%) and 5 females (17.9%), with age of (51.5±13.6) years. Among the 30 sides, 20 (66.7%) on the left and 10(33.3%) were on the right. Calculi were either located in the renal pelvis or calyxes in 7 sides (23.3%), upper ureter in 17 sides (56.7%), and lower ureter in 6 sides (20.0%). The maximum diameter of the stones was (9.4±4.2)mm, and 23 sides (76.7%) were combined with hydronephrosis before surgery. When "difficult ureter" was encountered during the procedure, that is, it was difficult to insert ureteroscope or ureteral access sheath (UAS) due to small ureteral lumen, balloon catheter was used for dilation in the first stage, in which the balloon diameter was 4 mm on 22 sides and 5mm on 8 sides. The instrument was retrogradely inserted through the working channel of F8 semi-rigid ureteroscope, and the small site of the ureteral lumen was dilated under direct endoscopic view. After a single dilation, the balloon catheter was withdrawn, and the effect of dilation was evaluated by semi-rigid ureteroscopy to determine whether to proceed with the following procedures. The intraoperative data were recorded, including surgical method, stage of "difficult ureter" occurred, site of the small part of the ureter, related data of utilizing ureteral dilatation balloon catheter, grade of ureteral injury after dilatation (according to the 0-4 grading classification of endoscopic ureteral injuries), total operation time, balloon catheter-related adverse events, stone-free rate, and time of removing ureteral stents.Results:Among the 30 sides, 29 (96.7%) had difficulty in the stage of ureteroscope insertion, and 1(3.3%) had difficulty in the stage of UAS insertion. A total of 37 small sites of ureter were involved, including 18 in the intramural segment, 10 in the lower part, 2 in the middle part, and 7 in the upper part. Each site was dilated once with a median time of 3 (0.5, 5.0) minutes and a median maximum balloon pressure of 1 215.9(1 215.9, 1 443.9)kPa[12.0(12.0, 14.3)atm]. There were 28 sites of grade Ⅰ injury, 8 sites of grade Ⅱinjury, and 1 site of grade Ⅲinjury. The total duration of unilateral procedure was (73.4±30.3) min. Ureteroscope or UAS insertion was successful in 28 sides(93.3%) after balloon dilation, and failed in 2 sides(6.7%), both of which were in the stage of inserting ureteroscope and ureteral stent was indwelled for the second-stage procedures. On the first day after surgery, the hemoglobin level was (134.1±12.9)g/L, which was significantly different from the preoperative parameters ( P<0.01), and serum creatinine level was (86.7±23.2)μmol/L, which showed no significant difference from the preoperative one ( P=0.263). The primary stone-free rate was 92.9% (26/28), and the total postoperative complication rate was 13.3% (4/30), including 3 of grade Ⅰ (lateral lower abdominal pain requiring additional analgesic drugs) and 1 of grade Ⅱ (postoperative hematuria requiring intravenous hemostatic drugs). Follow-up was conducted for 3 months. All of the 28 successful sides had their ureteral stents removed before the last follow-up, and the time of removal was (36.9±11.5) days. No hydronephrosis was found in the ipsilateral kidney by ultrasound 3 months after operation. Conclusions:Balloon dilation technique showed good efficacy and safety in the treatment of "difficult ureter" during ureteroscopic lithotripsy.