[Analysis of clinical presentation and genetic characteristics of malignant infantile osteopetrosis]

Objective: To investigate the clinical presentation and genetic characteristics of malignant infantile osteopetrosis. Methods: This was a retrospective case study. Thirty-seven children with malignant infantile osteopetrosis admitted into Beijing Children's Hospital from January 2013 to September 2022 were enrolled in this study. According to the gene mutations, the patients were divided into the CLCN7 group and the TCIRG1 group. Clinical characteristics, laboratory tests, and prognosis were compared between two groups. Wilcoxon test or Fisher exact test were used in inter-group comparison. The survival rate was estimated with the Kaplan-Meier method and the Log-Rank test was used to compare the difference in survival between groups. Results: Among the 37 cases, there were 22 males and 15 females. The age of diagnosis was 0.5 (0.2, 1.0) year. There were 13 patients (35%) and 24 patients (65%) with mutations in CLCN7 and TCIRGI gene respectively. Patients in the CLCN7 group had an older age of diagnosis than those in the TCIRGI group (1.2 (0.4, 3.6) vs. 0.4 (0.2, 0.6) years, Z=-2.60, P=0.008). The levels of serum phosphorus (1.7 (1.3, 1.8) vs. 1.1 (0.8, 1.6) mmol/L, Z=-2.59, P=0.010), creatine kinase isoenzyme (CK-MB) (457 (143, 610) vs. 56 (37, 82) U/L, Z=-3.38, P=0.001) and the level of neutrophils (14.0 (9.9, 18.1) vs. 9.2 (6.7, 11.1) ×109/L, Z=-2.07, P=0.039) at diagnosis were higher in the CLCN7 group than that in the TCIRG1 group. However, the level of D-dimer in the CLCN7 group was lower than that in the TCIRGI group (2.7 (1.0, 3.1) vs. 6.3 (2.5, 9.7) μg/L, Z=2.83, P=0.005). After hematopoietic stem cell transplantation, there was no significant difference in 5-year overall survival rate between the two groups (92.3%±7.4% vs. 83.3%±7.6%, χ²=0.56, P=0.456). Conclusions: TCIRGI gene mutations are more common in children with osteopetrosis. Children with TCIRGI gene mutations have younger age, lower levels of phosphorus, CK-MB, and neutrophils and higher level of D-dimer at the onset. After hematopoietic stem cell transplantation, patients with CLCN7 or TCIRGI gene mutations have similar prognosis.

[The incidence and risk factors of catheter-related-thrombosis during induction chemotherapy in acute lymphocytic leukemia children]

目的

分析初诊急性淋巴细胞白血病（ALL）诱导化疗期外周静脉穿刺中心静脉置管（PICC）患儿导管相关性血栓（CRT）的危险因素。

方法

收集2014年3月1日至2014年12月31日首都医科大学附属北京儿童医院血液肿瘤中心白血病病房行PICC置管的116例初诊ALL患儿临床资料。

结果

①PICC置管后第15天33例（28.4%）患儿发生CRT（CRT组），83例患儿未发生CRT（非CRT组）。②两组在性别、年龄分布、ALL危险度、免疫表型以及置管时两组血常规、凝血功能、是否合并感染、置管静脉方面差异无统计学意义，CRT组右侧置管比例高于非CRT组[75.8%（25/33）对55.4%（46/83），P=0.043]。③CRT组患者均无临床症状，置管第15天D-二聚体高于非CRT组[0.18（0.05~2.45）mg/L对0.11（0.01~5.34）mg/L，P=0.001]。④观察期中出现3例导管相关性并发症，均为导管相关性感染，其中2例并发CRT。⑤置管第33天CRT组26例患者复查B超，19例（73.1%）血栓缩小，6例（23.1%）无明显变化，1例（3.8%）增大。

结论

CRT是初诊ALL患儿诱导化疗期PICC置管的常见导管相关并发症，但症状出现较少，大部分血栓可自行缩小，右侧置管为CRT发生的危险因素；检测D-二聚体水平以及定期进行导管部位B超检查有助于及时发现CRT。

Modification of vectors for functional genomic analysis in plants

Simple, efficient, and economical recombinant plant binary expression vectors for deciphering large-scale functional genomic research in plants and promoting crop improvement by genetically engineering and biotechnology is in great demand. In this research, using the pCHF3, pCAMBIA1301, pCAMBIA3300, pCAMBIA3301 vectors, we successfully constructed general plant binary expression vectors carrying CaMV35S and Arabidopsis rd29A promoters mediating multiple cloning sites (

MCS

SacI, KpnI, SmaI, BamHI, XbaI, SalI, and PstI). Meanwhile, a series of applicative binary expression vectors that can be utilized for subcellular localization were constructed by fusion of the MCS and eGFP. Subsequently, the recombinant vectors were successfully transferred into Arabidopsis thaliana and Nicotiana benthamiana for further investigation of functional elements in these plant binary expression vectors. Our results demonstrated that this system was a convenient and versatile vector system for phenotypic, functional, subcellular localization, and promoter activity analysis, and it provided a relatively high-efficiency and reliable platform for researchers in vector construction and may facilitate large-scale functional genomics analysis in plants.

[Plasmid fingerprinting technique analysis of Pseudomonas aeruginosa isolated from a burn unit]

We used plasmid fingerprinting technique to analyse 50 strains of Pseudomonas aeruginosa isolated from our burn unit and 15 strains of Pseudomonas aeruginosa from other wards. The results revealed that the carrier rate of R-plasmid was 100%. All 50 strains of Pseudomonas aeruginosa from burn units contained one plasmid with approximate molecular weight of 55 kb. Among 15 strains of Pseudomonas aeruginosa from other wards, 10 strains contained one plasmid with the same molecular weight. However, 3 strains were found to possess an additional 12.5-kd plasmid and 2 strains contained 77-kb plasmid. This proves that R-plasmid carrying Pseudomonas aeruginosa is prevalent in the burn unit, and R-plasmid is disseminated in the hospital.