Objective To explore the prognostic significance of bone marrow examination at different time points by using different methods during induction therapy.Methods From Feb.2004 to Jan.2013,268 newly diagnosed (B acute lymphoblastic leukemia,B-ALL) pediatric patients in Peking University People's Hospital,were enrolled for the study.In this study,the overall survival (OS) ratio and event-free survival(EFS) ratio of patients with different bone marrow morphology on day 8 and day 15 were analyzed.Based on different cut off value of minimal residual disease (MRD) on day 15 and end-of-induction,the OS ratio and EFS ratio of the higher patients and the lower patients were compared.Results Patients with M1,M2 or M3 marrows on day 8 had no significant difference in OS ratio (P =0.372) or EFS ratio (P =0.393).When it came to day 15,patients with M1,M2 or M3 marrows had no significant difference in OS ratio (P =0.050) or EFS ratio (P =0.324).Patients with MRD ＞ 10.00％ on day 15 had lower OS ratio than those with MRD ≤ 10.00％,and it had significant difference(P =0.022).But there was no significant difference in EFS ratio (P =0.191).As for MRD on the end-of-induction,when using the MRD level of 0.0l ％,0.10％,1.00％ as cut-off values,the lower group of end-of-induction MRD was significantly associated with a higher probability of OS ratio and it had significant differences(P =0.018,0.006,0.002),and it showed the same results at EFS ratio (P =0.002,0.000,0.000).Conclusions The bone marrow morphology on day 8 and day 15 during induction therapy had no prognostic significance.The MRD of day 15 had prognostic significance when using 10.00％ as the cut off value.The critical value of MRD on the end-of-induction MRD should be 0.01％ for the prognosis.

Objective:To preliminarily explore the association of pregnancy factors with cow's milk protein allergy in infants.Methods:This study was based on data from a subcohort of a study called ge-netic susceptibility to cow's milk allergy in Chinese children,including infants born in Peking University People's Hospital between March 1,2020,and December 31,2020.The infants were divided into a cow's milk protein allergy(CMPA)group and a control group according to whether they had developed cow's milk protein allergy at the age of 1 year.We retrospectively collected the clinical data of infants and their mothers before and during pregnancy,and analyzed the association of multiple factors during pregnancy with cow's milk protein allergy in infants.Results:A total of 278 infants were enrolled in this study,including 52 infants with CMPA and 226 infants without CMPA.Among them,there were 143 boys and 135 girls.The proportion of male infants in the CMPA group(69.2％)was higher than that in the control group(47.3％),and the difference was statistically significant(P=0.004).There were no significant differences in the distribution of birth weight,gestational age at birth,low-birth-weight in-fants,premature,umbilical cord entangle neck,and neonatal asphyxia between the CMPA group and the control group(P＞0.05).The proportion of mothers complicated with autoimmune diseases,anemia or antibiotics exposure during pregnancy in the CMPA group was higher than that in the control group,and there were statistical differences between the two groups(P＜0.05).There was no significant difference in the distribution of other pregnancy complications between the two groups(P＞0.05),such as eclamp-sia/preeclampsia,chronic hypertension/gestational hypertension,diabetes/gestational diabetes,thyroid diseases,and so on.There was no significant difference in the overall distribution of some blood routine indexes during pregnancy between the CMPA group and the control group(P＞0.05).Multivariate Lo-gistic regression analysis showed that male infant,mothers complicated with autoimmune diseases or ane-mia,antibiotic exposure during pregnancy were independent risk factors for cow's milk protein allergy.Conclusion:Male infant,mothers complicated with autoimmune diseases or anemia,antibiotic exposure during pregnancy were independent risk factors for cow's milk protein allergy.

Objective:To study the current status of longitudinal extrauterine growth restriction (EUGR) in extremely preterm infants (EPIs) and to develop a prediction model based on clinical data from multiple NICUs.Methods:From January 2017 to December 2018, EPIs admitted to 32 NICUs in North China were retrospectively studied. Their general conditions, nutritional support, complications during hospitalization and weight changes were reviewed. Weight loss between birth and discharge > 1SD was defined as longitudinal EUGR. The EPIs were assigned into longitudinal EUGR group and non-EUGR group and their nutritional support and weight changes were compared. The EPIs were randomly assigned into the training dataset and the validation dataset with a ratio of 7∶3. Univariate Cox regression analysis and multiple regression analysis were used in the training dataset to select the independent predictive factors. The best-fitting Nomogram model predicting longitudinal EUGR was established based on Akaike Information Criterion. The model was evaluated for discrimination efficacy, calibration and clinical decision curve analysis.Results:A total of 436 EPIs were included in this study, with a mean gestational age of (26.9±0.9) weeks and a birth weight of (989±171) g. The incidence of longitudinal EUGR was 82.3%(359/436). Seven variables (birth weight Z-score, weight loss, weight growth velocity, the proportion of breast milk ≥75% within 3 d before discharge, invasive mechanical ventilation ≥7 d, maternal antenatal corticosteroids use and bronchopulmonary dysplasia) were selected to establish the prediction model. The area under the receiver operating characteristic curve of the training dataset and the validation dataset were 0.870 (95% CI 0.820-0.920) and 0.879 (95% CI 0.815-0.942), suggesting good discrimination efficacy. The calibration curve indicated a good fit of the model ( P>0.05). The decision curve analysis showed positive net benefits at all thresholds. Conclusions:Currently, EPIs have a high incidence of longitudinal EUGR. The prediction model is helpful for early identification and intervention for EPIs with higher risks of longitudinal EUGR. It is necessary to expand the sample size and conduct prospective studies to optimize and validate the prediction model in the future.