A quartz crystal microbalance(QCM)-systematic evolution of ligands by the exponential en-richment(SELEX)technique was developed to screen out aptamers with high affinity for arsenic(Ⅲ).A random single strand DNA library was designed and fixed on the mercaptoethylamine-modified crystal plate with arsenic(Ⅲ)as the target,and the free aptamer was captured in the solution,and the QCM-SELEX screening method was constructed.After 6 rounds of screening,the secondary library was se-quenced with high throughput method,and the 6S1 dissociation coefficient Kd value was 0.36 μmol/L based on QCM resonance frequency.Using 6S1 as a probe,the QCM biosensor was constructed for the detection of arsenic(Ⅲ).The sensor has a good linear relationship in the range of 0.01 μmol/L～0.2μmol/L,and the detection limit of arsenic(Ⅲ)is 5.2 nmol/L(3σ),indicatinggood selectivity.

Objective:To study the reversal effect of NVP-BEZ235 on doxorubicin resistance in Burkitt lymphoma RAJI cell line.Methods:The doxorubicin-resistant cell line was induced by treating RAJI cells with a concentration gradient of doxorubicin.The levels of Pgp,p-AKT,and p-mTOR in cells were detected by Western blot.Cell viability was detected by MTT assay.IC50 was computed by SPSS.Results:The doxorubicin-resistant Burkitt lymphoma cell line,RAJI/DOX,was established successfully.The expression of Pgp and the phosphorylation levels of AKT and mTOR in RAJI/DOX cell line were both higher than those in RAJI cell line.NVP-BEZ235 downregulated the phosphorylation levels of AKT and mTOR in RAJI/DOX cell line.NVP-BEZ235 inhibited the proliferation of RAJI/DOX cell line,and the effect was obvious when it was cooperated with doxorubicin.Conclusion:The constitutive activation of PI3K/AKT/mTOR pathway of RAJI/DOX cell line was more serious than RAJI cell line.NVP-BEZ235 reversed doxorubicin resistance of RAJI/DOX cell line by inhibiting the PI3K/AKT/mTOR signal pathway.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective To investigate the social support needs of medical staff in Guangzhou during the post-COVID-19 period,providing a basis for relevant departments to offer targeted social support for medical staff in Guangzhou and improve their of occupational quality of life.Methods A cross-sectional survey was conducted,employing a combination of quota and conven-ience sampling to select subjects,eligible medical staff were invited to complete an online questionnaire.Results The social sup-port with a total score of 20 for medical staff in Guangzhou scored 9(7,11).Among the dimensions of social support,media sup-port scored the lowest.Social support as a whole scored with statistically significant differences across groups of different age,ed-ucational background,and job position(all P＜0.05).The median score was the lowest for those under 25 years,for those with a college degree or below,and highest among administrative staff,with other positions showing equal median score.The five di-mensions of social support ranked on the top concerning the total number of the respondents included patients'understanding and trust for medical staff(93.03％),increasing in salaries and benefits(86.06％),accurate policy promotion and public opinion guidance by media(83.41％),attention to the living conditions of medical staff by media(80.29％),and enhanced regulation of false reporting and inappropriate commentary by media(76.92％).Medical staff under the age of 25 had a high need for pa-tients'following doctor's advice,and medical staff with a collegiate degree or below had a high need for family members or friends to care about their physical and mental health.The five strongest needs for social support ranked on the top concerning the total number of respondents included understanding and trust from patients(75.72％),increased salaries and benefits(53.85％),assistance with household matters by family or friends(42.55％),correct policy promotion and public opinion guidance by media(34.62％),and attention to the living conditions of medical staff from media(33.41％).Conclusion Social support for medical staff in Guangzhou are at a relatively low level,indicating a need for social support from all levels of society.

Objective:To summarize the clinical characteristics of suicidal behavior in children and provide a reference for further developing strategies for preventing childhood suicide.Methods:The medical records of children hospitalized in the pediatric intensive care unit（PICU）at Beijing Children's Hospital for suicidal behavior in the electronic medical record system from January 1,2018,to December 31,2022 were retrospectively selected.Clinical data of children with suicidal behavior were collected.Results:A total of 3 249 patients were admitted to the PICU,including 62 suicide patients.There were 20(32.3%) males,and 42(67.7%) females,with a male-to-female ratio of 1:2.1.The average age was (13.1 ± 1.5) years old,with a minimum age of 7.9 years and a maximum age of 15.7 years.There were 17 (27.4%) children with previously diagnosed mental illnesses.Notably 58.1% children had triggering factors for suicidal behavior.Analysis of suicide methods,53(85.5%) cases were intentional drug ingestion,six(9.7%) cases were jumping from height,and three(4.8%) cases were hanging.Additionally 26.4% cases of poisoning were male,while 66.7% of cases of jumping from height and hanging were male.There was a statistical difference in suicide methods between genders (χ 2=5.704, P=0.025).The poisoning ingestions were classified as 20(37.7%) cases of toxins; 14(26.4%) cases of antidepressants; 10(18.9%) cases of over-the-counter drugs; five(9.4%) cases of other prescription drugs; three(5.7%) cases of sedative drugs; one(1.9%) case of daily chemical.Sources of ingestions: 18(34.0%) cases were purchased personally (pharmacies or online shopping); 16(30.2%) cases were storing medicines at home; 13(24.5%) cases were daily taking antidepressants.Compared with non-poisoning patients,poisoning patients had a significantly shorter PICU duration (Z=-2.884, P=0.004).The total mortality rate of children admitted to PICU due to suicide was 16.1%(10/62).There was a statistical difference in the mortality rate among different suicide methods (χ 2=7.883, P=0.019). Conclusion:School aged children and boys are more likely to choose impulsive and more harmful suicide behaviors such as jumping from heights and hanging,and adolescent girls are more likely to choose intentional poisoning as their suicide method.Attention should be paid to the suicide risk of different age and gender groups.Intentional drug ingestion is the main method of suicide in children.Herbicide poisoning and antidepressant drug poisoning are the leading causes of suicide death.The death risk of suicidal behavior in children may be reduced by controlling the way of getting pesticides (especially herbicides) and obtaining maximum doses of antidepressants.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To develop effective measures to reduce antibiotic use duration in very low birth weight(VLBW)preterm infants in the neonatal intensive care unit through quality improvement methods.Methods The study population consisted of hospitalized VLBW preterm infants,with the percentage of hospitalization time during which antibiotics were used from November 2020 to June 2021 serving as the baseline.The specific quality improvement goal was to reduce the duration of antibiotic use.Factors affecting antibiotic use duration in preterm infants were analyzed using Pareto charts.Key drivers were identified,and specific interventions were formulated based on the stages of antibiotic use.Changes in the percentage of antibiotic use duration were monitored with run charts until the quality improvement target was achieved.Results From November 2020 to June 2021,the baseline antibiotic use duration percentage was 49%,with a quality improvement target to reduce this by 10%within 12 months.The Pareto analysis indicated that major factors influencing antibiotic duration included non-standard antibiotic use;delayed cessation of antibiotics when no infection evidence was present;prolonged central venous catheter placement;insufficient application of kangaroo care;and delayed progress in enteral nutrition.The interventions implemented included:(1)establishing sepsis evaluation and management standards;(2)educating medical staff on the rational use of antibiotics for preterm infants;(3)supervising the enforcement of antibiotic use standards during ward rounds;(4)for those without clear signs of infection and with negative blood cultures,discontinued the use of antibiotics 36 hours after initiation;(5)reducing the duration of central venous catheterization and parenteral nutrition to lower the risk of infection in preterm infants.The control chart showed that with continuous implementation of interventions,the percentage of antibiotic use duration was reduced from 49%to 32%,a statistically significant decrease.Conclusions The application of quality improvement tools based on statistical principles and process control may significantly reduce the antibiotic use duration in VLBW preterm infants.

Objective To investigate the clinical features and prognosis of children with fungal bloodstream infection(BSI)following chemotherapy for acute leukemia(AL).Methods A retrospective analysis was performed on 23 children with fungal BSI following chemotherapy for AL in three hospitals in Fujian Province,China,from January 2015 to December 2023.Their clinical features and prognosis were analyzed.Results Among all children following chemotherapy for AL,the incidence rate of fungal BSI was 1.38%(23/1 668).At the time of fungal BSI,87%(20/23)of the children had neutrophil deficiency for more than one week,and all the children presented with fever,while 22%(5/23)of them experienced septic shock.All 23 children exhibited significant increases in C-reactive protein and procalcitonin levels.A total of 23 fungal isolates were detected in peripheral blood cultures,with Candida tropicalis being the most common isolate(52%,12/23).Caspofungin or micafungin combined with liposomal amphotericin B had a relatively high response rate(75%,12/16),and the median duration of antifungal therapy was 3.0 months.The overall mortality rate in the patients with fungal BSI was 35%(8/23),and the attributable death rate was 22%(5/23).Conclusions Fungal BSI following chemotherapy in children with AL often occurs in children with persistent neutrophil deficiency and lacks specific clinical manifestations.The children with fungal BSI following chemotherapy for AL experience a prolonged course of antifungal therapy and have a high mortality rate,with Candida tropicalis being the most common pathogen.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

This study investigated the effect of different carrier materials on the in vitro properties of progesterone solid dispersions. The solid dispersions of the insoluble drug progesterone were prepared by hot melt extrusion technique using rheological properties as the index of investigation, and the in vitro properties of the solid dispersions were characterized. Scanning electron microscope revealed solid dispersions with rough surfaces and agglomerated microstructures into irregular lumpy particles. Differential scanning calorimetry and powder X-ray diffraction showed the change of progesterone crystalline form in solid dispersions from crystalline to amorphous state. In vitro dissolution studies showed that solid dispersions prepared with different carrier materials can effectively improve the dissolution rate of drugs. The results of the study showed that the type of carrier material had a significant effect on the in vitro properties of solid dispersions, providing a reference for the study of solid dispersions in the controlled release of insoluble drugs.