In recent years,with the continuous progress of DNA extraction and detection technology,cell-free DNA(cfDNA)has been widely used in the life science field,and its potential application value in forensic identification is becoming more and more obvious.This paper reviews the concept,formation mechanism,and classification of cfDNA,etc.,and describes the latest research progress of cfDNA in personal identification of crime scene touch DNA samples and non-invasive prenatal pater-nity testing(NIPPT).Meanwhile,this paper summarizes the potential application of cfDNA in injury inference,and discusses the advantages and disadvantages of common cfDNA analysis methods and techniques,and its application prospects,to provide a new idea for the wide application of cfDNA in the field of forensic science.

Objective To investigate the mechanism of matrine hydrochloride injection on acetaminophen(APAP)induced liver injury in mice.Methods Sixty male Kunming mice were randomly divided into blank group,model group and experimental-L,-M,-H groups.The mice were abdominal injected 300 mg·kg-1 APAP to build the acute liver injury modeling.The experimental-L,-M,-H groups were intravenous injected matrine of 0.7,1.4,and 2.8 mg·kg-1,respectively.Blank and model groups were injected with 10％glucose solution 10 mL·kg-1·d-1 via tail vein.Enzyme-linked immunosorbent assay were used to measure the levels of glutamic oxaloacetic transaminase(GOT),glutamic oxaloacetic transaminase(GPT),interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)in mice serum.The kit were employed to detect the levels of superoxide dismutase(SOD)and malondialdehyde(MDA)in liver tissue.Results The serum GOT levels in the experimental-M,-H groups,model group and blank group were(5 593.45±128.46),(2 316.24±125.37),(8 302.16±267.15)and(40.13±7.69)U·L-1;the GPT levels were(6 159.37±129.64),(2 597.10±120.37),(8 1699.54±259.87)and(36.47±9.46)U·L-1;the IL-6 levels were(159.43±26.42),(96.37±25.84),(215.34±47.68)and(83.72±26.37)pg·mL-1;the TNF-α levels were(327.68±38.37),(249.69±44.97),(477.68±58.59)and(254.35±50.67)pg·mL-1;the SOD levels were(329.46±37.49),(371.16±33.76),(246.84±38.79)and(429.67±23.76)U·mg-1;the MDA levels were(5.34±0.76),(4.09±0.54),(12.46±3.76)and(3.12±0.42)nmol·mg-1.There were significant differences between the experimental-M,-H groups and the model group(all P＜0.05).Conclusion Matrine has a significant protective effect on APAP induced drug-induced liver injury,and its protective mechanism is related to inhibiting inflammatory response and alleviating oxidative stress response.

Objective To establish a high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method for simultaneous determination of meropenem,linezolid,voriconazole and posaconazole in children with small volume of plasma,and to use the method in children therapeutic drug monitoring(TDM).Methods The plasma samples were precipitated protein by methanol.And then,the analytes were gradient eluted on an EVO-C18 column by HPLC-MS/MS with mobile phase consisted of water(0.1％formic acid)-acetonitrile(0.1％formic acid)at the flow rate of 0.5 mL·min 1.Ions were monitored in the multiple reaction monitoring(MRM)mode,using positive ion electrospray ionization(ESI).Results Meropenem had a good liner relationship in 0.5-64.0 μg·mL-1(r=0.999 2),0.2-25.6 μg·mL-1 for linezolid and voriconazole(r=0.999 2,r=0.999 9),and 0.1-12.8 μg·mL-1 for posaconazole(r=0.998 9).Accuracy,precision,matrix effect and stability studies all met the requirements.This method was fully verified,and applied to determine the plasma antimicrobial concentrations of 49 pediatric patients.Conclusion The method is simple,rapid,sensitive and suitable for children's plasma concentration monitoring of four antimicrobials.

Objective:To conduct a survey of the current status of education service offered to professional master's students in clinical medicine in a grade-A tertiary hospital in Chongqing, China based on the SERVQUAL model, and to discuss the problems with education service as well as measures for improvement.Methods:Based on the SERVQUAL model, a questionnaire consisting of 30 items in 5 dimensions was designed. Each item was rated for an expected score and a perceived score. Medical professional master's students in a Chongqing grade-A tertiary hospital in the first half year of 2022 were surveyed for the expected and perceived quality of education service to calculate service quality (SQ). SPSS 26.0 was used for reliability and validity analyses and descriptive statistical analyses. The results were analyzed using a two-dimensional quadrant graph.Results:A total of 263 valid questionnaires were returned, with an effective response rate of 97.77%. For both the expectation scale and the perception scale, the Cronbach's α values were >0.8, and the Kaiser-Meyer-Olkin values were >0.7, indicating good reliability and validity. The mean expected value of education service quality was 4.28, the mean perceived value was 3.96, and the mean gap value was -0.32. The SQ scores for all the items were negative, except for "provide neat suits for work". The two-dimensional quadrant analysis showed that 6 items were located in quadrant III (low-expectation and low-perception area), and 7 items were located in quadrant IV (high-expectation and low-perception area).Conclusions:The evaluation scale based on the SERVQUAL model can effectively reflect problems in postgraduate education for medical master's students, helping develop strategies to improve the quality of education service.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.

Objective:This study analyzed the provincial policy on the"dual channel"management of drugs,provided suggestions for improving the"dual channel"management models.Methods:From May 10,2021 to April 10,2024,the official websites of the Healthcare Security Administration and the Health Commission of various provinces were searched for policy documents related to the"dual channel"management,and the text data were statistically analyzed.Results:The"dual-channel"management policies of various provinces coexisted with commonalities and differences.Conclusions:It is recommended to refine the access standards of the drug catalog,standardize the setting of the entry threshold of pharmaceutical institutions,scientifically determine the level of medical insurance treatment,and formulate differentiated drug identification and management methods,so as to further weaken the policy restrictive factors.

Objective To investigate the differences of characteristic of bone marrow plasma cells in patients of different plasma cell dyscrasias according to International Myeloma Working Group(IMWG)criteria.Methods We analyzed the serological and bone marrow flow cytometry results of patients with plasma cell dyscrasias diagnosed and treated in Department of Hematology,Zhongshan Hospital(Xiamen Branch),Fudan University from Jun 12,2019 to Sep 5,2023 retrospectively.Results A total of 102 patients,63 males and 39 females,aged 22 to 85 years,were included,including 46 patients with monoclonal gammaglobulinemia of unknown significance,39 patients with multiple myeloma,5 patients with smoldering multiple myeloma and 12 patients with light-chain amyloidosis.All patients had M proteinemia,including 58 patients with IgG type and 44 patients with non-IgG type.Plasma cells were detected in the bone marrow of all patients.Clonal plasma cells were detected in the bone marrow of 79 patients.Normal plasma cells were detected in the bone marrow of 63 patients.Both clonal and normal plasma cells were detected in the bone marrow of 40 patients.Clonal plasma cells from bone marrow of 52 patients expressed CD56 and 12 patients expressed CD117.There were no significant differences in gender,age among different disease groups.There were statistical differences in M protein type,the concentration of M protein,serum involved/uninvolved free light chain ratio,the proportion of plasma cells in bone marrow nucleated cells,the proportion of clonal plasma cells in bone marrow nucleated cells,the proportion of clonal plasma cells in all bone marrow plasma cells,and the proportion of normal plasma cells in all bone marrow plasma cells among different disease groups(P<0.05).There was statistical difference in the expression of CD56 in clonal plasma cells among different disease groups(P=0.009),but no statistical difference in the expression of CD117.Conclusion The proportion of clonal plasma cells to all nucleated cells,the proportion of clonal plasma cells to all plasma cells,and the proportion of CD56 expression in abnormal plasma cells in the bone marrow of patients with light amyloidosis were similar to those of monoclonal gammopathy of undetermined significance,but significantly different from those of patients with multiple myeloma.

Objective:To evaluate the efficacy and safety of first-line anti-tuberculosis (TB) drugs combined with linezolid in treatment of children with tuberculous meningitis (TBM).Methods:A retrospective cohort study design was performed . Eight-nine Children diagnosed as TBM during January 1 st 2016 and December 31 st 2023 in Department of Infectious Disease, Children′s Hospital of Chongqing Medical University were enrolled in the study. According to different treatment regimens, children were divided into a group of first-line anti-tuberculous drugs (isoniazid, rifampicin, pyrazinamide, ethambutol (HRZE)) and a group of HRZE and linezolid combination (HRZEL). The efficacy and safety of the 2 regimens were compared and the relationship between linezolid drug concentration and adverse reactions were analyzed. Comparisons between groups were performed using χ2 test and Mann-Whitney U test. Results:The 89 children with TBM included 53 males and 36 females with an onset age of 4.6 (1.4, 9.6) years. There were 27 cases in the HZREL group and 62 cases in the HRZE group. Before treatment, positive rate of interferon-gamma release assays (IGRA) in HRZEL group was lower than that in HRZE group (64% (16/25) vs.92% (55/60), χ2=9.82, P<0.05), but protein level of cerebrospinal fluid (CSF) was higher than that in HRZE group (1.2 (1.0, 2.0) vs.0.8 (0.4,1.4) g/L, Z=0.32, P<0.05). By the end of the intensive phase, there were no significant differences of rates of CSF improvement and etiology negativity between HRZEL group and HRZE group (both P>0.05).The 44 TBM children with high CSF protein (>1 g/L) included 25 males and 19 females with an onset age of 6.7 (3.0, 11.8) years. There were 21 cases in the HZREL group and 23 cases in the HRZE group accordingly. Before treatment, there were no significant differences of positive rate of IGRA test and CSF protein level between the 2 groups (62% (13/21) vs. 87% (20/23), 1.7 (1.1, 2.2) vs. 1.5 (1.2, 1.9) g/L, χ2=3.67, Z=0.23, both P>0.05). There were no significant differences in CSF indicators, etiology negativity or imaging remission between the two groups by the end of intensive phase (all P>0.05). Higher frequencies of granulocytopenia, gastrointestinal symptoms as well as withdrawal or change of drugs were found in HRZEL group when compared to those in HRZE group (44% (12/27) vs. 19% (12/62), 7% (2/27) vs. 0, 33% (9/27) vs. 3% (2/62), χ2=6.01, 4.70, 15.74, all P<0.05). Conclusions:The efficacy of HRZEL regimen is similar to conventional HRZE regimen in children with TBM, but with higher adverse effect. Prudentially evaluating the pros and cons of linezolid in the usage of drug-susceptible TB and carefully monitoring of linezolid associated adverse effects is suggested.

Objective To explore the mechanism of Zhuangxuan Yin in the treatment of children with H1N1 pneumonia through regulating gut microbiota mediated by p38 mitogen-activated protein kinase(p38-MAPK)pathway.Methods A BALB/c mouse model of H1N1 pneumonia was prepared using the H1N1 influenza virus allantoic solution for nasal drop.The model was randomly separated into 5 groups:model group,Zhuangxuan Yin low-,medium-and high-dose groups,and high-dose Zhuangxuan Yin(28.66 g·kg-1)+anisomycin(10 mg·kg-1)group.The control group was infused with sterile physiological saline of equal volume using the same method.After treatment with Zhuangxuan Yin and anisomycin,the lung index of mice in each group was measured,and HE staining was applied to detect the pathological morphology of lung and large intestine tissues.16SrRNA gene sequencing was applied to detect the structural difference of gut microbiota in mice of each group.Enzyme-linked immunosorbent assay(ELASA)was applied to measure the levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-4,IL-6,and IL-1β in bronchoalveolar lavage fluid(BALF)and large intestine tissue of mice in each group.Western Blot was applied to detect the expression of p38-MAPK pathway-related proteins in lung and large intestine tissues of mice in each group.Results Compared with the control group,the lung and large intestine tissues of the model group mice showed obvious pathological damage,the lung index,pathological score of lung and large intestine,ACE index,Shannon index,abundance of class Clostridia,the levels of TNF-α,IL-4,IL-6,and IL-1β in BALF and large intestine tissues,and p-p38-MAPK/p38-MAPK in lung and large intestine tissues increased(P＜0.05).The abundance of class Bacteroidales decreased(P＜0.05).Compared with the model group,the pathological damage in the lung and large intestine tissues of mice in the Zhuangxuan Yin low-,medium-and high-dose groups were reduced.The lung index,pathological score of lung and large intestine,ACE index,Shannon index,abundance of class Clostridia,the levels of TNF-α,IL-4,IL-6,and IL-1β in BALF and large intestine tissues,and p-p38-MAPK/p38-MAPK in lung and large intestine tissues decreased(P＜0.05),the abundance of class Bacteroidales increased(P＜0.05),and in a dose-dependent manner(P＜0.05).Compared with the high-dose Zhuangxuan Yin group,the pathological damage in the lung and large intestine tissues of mice in the high-dose Zhuangxuan Yin+anisomycin group was aggravated,the lung index,pathological score of lung and large intestine,ACE index,Shannon index,abundance of class Clostridia,the levels of TNF-α,IL-4,IL-6,and IL-1β in BALF and large intestine tissues,and p-p38-MAPK/p38-MAPK in lung and large intestine tissues increased(P＜0.05),and the abundance of class Bacteroidales decreased(P＜0.05).Conclusion Zhuangxuan Yin can improve the imbalance of intestinal microbiota in H1N1 pneumonia mice by inhibiting p38-MAPK signal activation,thereby inhibiting inflammation and reducing lung and large intestine tissue damage in mice,which may have a therapeutic effect on children with H1N1 pneumonia.