Objective To analyze the atrioventricular synchronization rate after implantation of Micra AV leadless pacemaker,and the impact of postoperative programming optimization on atrioventricular synchronization rate.Methods A prospective cohort study was conducted to select patients with complete atrioventricular block who underwent Micra AV leadless pacemaker implantation at Beijing Anzhen Hospital from August 2022 to June 2023.Programming optimization were performed at 1 week,1 month,and 3 months postoperatively,and atrioventricular synchronization rate,electrical parameters,and echocardiography were recorded.Results A total of 68 patients with complete atrioventricular block implanted with Micra AV were selected,with an average age of(68.2±9.7)years,including 47 males(69.1％).All patients were successfully implanted with Micra AV,and there were no serious postoperative complications;The average threshold,sense,and impedance parameters were stable during 1 week,1 month,and 3 months after the procedure;There was no significant difference in the EF value of postoperative echocardiography(P=0.162);The average atrioventricular synchronization rates at 1 week,1 month,and 3 months postoperatively were(75.2％vs.83.8％vs.91.6％,P=0.001).Conclusions As an mechanical atrial sensing,Micra AV requires personalized adjustment of relevant parameters;Postoperative follow-up programming optimization plays an important role in the atrioventricular synchronization and comfort level in patients with complete atrioventricular block after implantation of Micra AV leadless pacemaker.

Objective To explore specific magnetic resonance imaging(MRI)features of somatic symptoms in depression by comparing the differences of brain gray matter volume in depression patients with and without somatic symptoms using voxel-based morphometry(VBM).Methods A total of 52 depression patients were recruited and divided into somatic and no somatic symptoms group according to the patient health questionnaire-15 score(＞9 and≤9,respectively).Forty gender-age-matched healthy volunteers were recruited as the control group.All subjects underwent MRI scanning.Imaging data were analyzed to explore the differences in brain gray matter between groups using VBM.Results Compared with control group,gray matter volume increased in the right superior temporal gyrus,and decreased in the right inferior orbitofrontal gyrus,right inferior temporal gyrus,left inferior orbitofrontal gyrus,and left superior temporal gyrus for depressive patients with somatic symptoms(P＜0.001);gray matter volume increased in the right middle temporal gyrus,and decreased in the right superior temporal gyrus and right inferior temporal gyrus for depressive patients without somatic symptoms(P＜0.001).Only the volume in the right tongue and left cingulate gyrus increased in depressive patients with somatic symptoms compared with that in patients without somatic symptoms(P＜0.01).Conclusion VBM-MRI has demonstrated increased volume in the tongue and cingulate gyrus in the somatic symptoms of depression.

An integrated evaluation model based on the combination of traditional trait identification and modern chemical analysis was used for the identification of key indexes of grade classification and the establishment of grade quality standard of Lycium barbarum fruits (LBF) from Ningxia genuine producing area. Under the guidance of herbal examination and market survey, particle size, skin color and imperfection were taken as the external trait indicators; focusing on the comprehensiveness and validity of the quality evaluation, 2-O-β-D-glucopyranosyl-L-ascorbic acid (AA-2βG), zeaxanthin dipalmitate (ZD) and volatile ether extractives were used as important parameters involving in quality evaluation in addition to the pharmacopoeia test items and determination indicators such as moisture, ash, water-soluble extractives, Lycium barbarum polysaccharide (LBP) and betaine. The quality differences between different traits and grades of LBF as well as the relevance between character and quality were further investigated by mathematical and statistical means such as t-test analysis, correlation analysis and principal component analysis (PCA). Furthermore, the activities of extractives from different grades of LBF were compared at cellular level. The results showed that LBF were mainly preferred for large and red ones; except for betaine, the other index components were relatively high (moisture and ash were low) in the first-grade and samples with bright-red skin color. Besides, there was a significant correlation between skin color and moisture, water-soluble extractives, LBP, AA-2βG and ZD contents. Considering the results of the study and the market situation, the present study took the grain size and skin color of LBF as the core of evaluation, and at the same time introduced the multi-indicator components including LBP, AA-2βG, ZD, water-soluble extractives and moisture to further guide the grading, and established the quality standard of LBF grades combining the trait indexes and the chemical composition. More importantly, in vitro cell models both preliminarily confirmed that the first-grade LBF played a more significant "nourishing liver and kidney" effect, which provided an experimental basis for the quality control of LBF and promoted the realization of high quality and good price.

Objective To compare the effect of internal iliac artery block using balloon of different properties in cesarean section for delivery female patients with pernicious placenta previa(PPP).Methods The clinical data of 82 delivery female patients with PPP were retrospectively analyzed.The patients were divided into observation group(n=40)and control group(n=42).The patients of the observation group received compliant Fogarty balloon block of bilateral internal iliac arteries,while the patients of the control group received non-compliant balloon block of bilateral internal iliac arteries.The preoperative and postoperative systolic blood pressure and heart rate,X-ray fluoroscopy time,fetal body surface radiation dose,time spent for cesarean section,intraoperative blood loss amount and blood transfusion quantity,uterine artery embolization rate,hysterectomy rate,1-,5-,and 10-minute neonatal Apgar scores,postoperative hospital stay,and surgery-related complications were compared between the two groups.Results In all patients of both groups,the uterus was successfully preserved and the bilateral internal iliac artery balloon obstruction-assisted cesarean section was successfully accomplished.After the balloon catheter was withdrawn,uterine artery embolization was carried out in some patients,and no patient received ovarian artery embolization and hysterectomy.No statistically significant differences in preoperative,postoperative systolic blood pressure and heart rate existed between the two groups,but in both groups the postoperative systolic blood pressure and heart rate were lower than their preoperative values(all P＜0.05).No statistically significant differences in X-ray fluoroscopy time,fetal body surface radiation dose,uterine artery embolization rate,hysterectomy rate,1-,5-,and 10-minute neonatal Apgar scores,and postoperative hospital stay existed between the two groups.In the observation group the time spent for cesarean section,intraoperative blood loss amount and blood transfusion quantity were lower than those in the control group(all P＜0.05).The difference in the incidence of balloon obstruction-related complications between the two groups was not statistically significant.Conclusion In cesarean section for delivery female patients with PPP,balloon block of bilateral internal iliac,regardless of using compliant Fogarty balloon catheter or non-compliant balloon catheter,is clinically safe and effective.However,the use of compliant Fogarty balloon catheter is superior to the use of non-compliant balloon catheter in reducing the cesarean section operative time,intraoperative blood loss amount,and intraoperative blood transfusion quantity.

Objective To explore the treatment of infection after spinal internal fixation.Methods The clinical data of 6 patients with infection after spinal internal fixation in our hospital were analyzed retrospectively.The bacterial culture and drug susceptibility testing were performed to identify the pathogenic bacteria and sensitive antibiotics.Moxifloxacin and/or vancomycin were used empirically for anti-infective therapies first,and then sensitive antibiotics were used according to the results of bacterial culture and drug susceptibility testing.At the same time,imaging examination was performed to determine the infection site and internal fixation,and surgical treatment was decided based on the patients'condition.After operation,the body temperature,inflammatory indexes and drainage of patients were monitored continuously,and the drainage fluid was taken for bacterial culture regularly to evaluate the therapeutic effect.Results The results of bacterial culture in 5 patients were positive and the pathogenic bacteria was staphylococcus aureus,with the susceptibility to vancomycin by susceptibility testing.Among them,1 patient was treated with vancomycin for about 8 weeks because of his advanced age,more basic diseases and high risk of operation;the other 4 patients were received surgery combined with anti-infective treatment with vancomycin for 2 to 4 weeks.One case with negative bacterial culture received surgery combined with anti-infective treatment with imipenem and moxifloxacin.The wound of all patients healed in grade A,the body temperature and inflammatory indexes returned to normal,the low back pain disappeared,and the nerve root symptoms of lower extremities were significantly improved.Conclusion Once the patients with infection after spinal internal fixation are diagnosed,the pathogenic bacterial should be identified as early as possible and sensitive antibiotics should be used.Meanwhile,the internal fixation is removed or re-implanted depending on whether it is infected.

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 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.

BACKGROUND: The addition of growth factiors is commonly applied to improve the osteogenic differentiation of stem cells. However, for human pluripotent stem cells (hPSCs), their complex differentiation processes result in the unknown effect at different stages. In this study, we focused on the widely used bone forming peptide-1 (BFP-1) and investigated the effect and mechanisms of its addition on the osteogenic induction of hPSCs as a function of the supplementation period. METHODS: Monolayer-cultured hPSCs were cultured in osteogenic induction medium for 28 days, and the effect of BFP-1 peptide addition at varying weeks was examined. After differentiation for varying days (0, 7, 14, 21 and 28), the differentiation efficiency was determined by RT–PCR, flow cytometry, immunofluorescence, and alizarin red staining assays. Moreover, the expression of marker genes related to germ layers and epithelial-mesenchymal transition (EMT) was investigated at day 7. RESULTS: Peptide treatment during the first week promoted the generation of mesoderm cells and mesenchymal-like cells from hiPSCs. Then, the upregulated expression of osteogenesis marker genes/proteins was detected in both hESCs and hiPSCs during subsequent inductions with BFP-1 peptide treatment. Fortunately, further experimental design confirmed that treating the BFP-1 peptide during 7–21 days showed even better performance for hESCs but was ineffective for hiPSCs. CONCLUSION The differentiation efficiency of cells could be improved by determining the optimal treatment period.Our study has great value in maximizing the differentiation of hPSCs by adding osteogenesis peptides based on the revealed mechanisms and promoting the application of hPSCs in bone tissue regeneration.

ObjectiveTo explore the role of structural MRI in the diagnosis of spinocerebellar ataxia type 3 （SCA3） and further evaluate its correlation with disease severity and disease duration. MethodsWe prospectively enrolled 81 genetically diagnosed SCA3 patients ［59 symptomatic （sym-SCA3） and 22 pre-symptomatic （pre-SCA3）］ and 35 age- and sex-matched healthy controls （HCs）. MRI structural images （3D T1 MPRAGE） and clinical data of all subjects were collected. Three observers with different radiological experience measured the width of the superior， middle and inferior cerebellar peduncle （SCP， MCP and ICP）， the anterior-posterior diameters of the pons and spinal cord at the levels of the foramen magnum and upper edge of the 3rd-5th cervical vertebra. One observer performed the measurements again 2 months later to assess for the intra- and inter-observer reliability， respectively. One-way ANOVA， rank-sum test， ROC curve and Random Forest were used to evaluate the diagnostic value of the above metrics for SCA3， and the correlation between the metrics and clinical variables was analyzed. ResultsNot depending on the radiological experience， the metrics based on morphological MRI showed high intra- and inter-observer reliability， among which bilateral superior and middle cerebellar peduncles performed best. The diameters of bilateral SCP， MCP， ICP， pons and spinal cord （except spinal cord at the level of the upper edge of the 5th cervical vertebra） decreased successively in HCs， pre-SCA3 and sym-SCA3 with a statistical difference （P<0.017）. ROC analysis revealed that the left MCP had the highest diagnostic value for pre-SCA3 （AUC=0.911）， with sensitivity， specificity and a cut-off value of 85.7%， 95.5% and 10.15 mm， respectively. In contrast， the right SCP had the highest diagnostic value for sym-SCA3 （AUC=0.999）， with sensitivity， specificity and a cut-off value of 100%， 98.3% and 2.62 mm， respectively. The Random Forest model based on the above metrics also had high diagnostic efficiency （AUC= 0.970， specificity=93.1%）， and the left MCP contributed the most. Correlation analysis showed that the above metrics had a significantly or moderately negative correlation with the Scale for the Assessment and Rating of Ataxia （SARA） and disease duration （P<0.05）. ConclusionNot depending on radiological experience， measurements of brain structure based on morphological MRI are reliable， which can help diagnose SCA3 and predict disease severity and duration. The left MCP and the right SCP perform best for predicting pre-SCA3 and sym-SCA3， respectively. Therefore， the structural MRI is recommended for assisting the clinical diagnosis of SCA3.

Size and surface modification are the two key factors affecting the effect of macrophages polarization induced by superparamagnetic iron oxide nanoparticles (SPIONs). The smaller the particle size, the better the polarization effect of SPIONs. Besides, the reasonable SPIONs surface modification method can also be used to enhance the polarization effect. In this study, SPIONs was prepared by solvothermal method and optimized by Box-Benhnken center combination design and response surface method. Furthermore, astragalus polysaccharide-superparamagnetic iron oxide nanocomplex (APS-SPIONs) was successfully constructed by EDC/NHS esterification method. The structure of APS-SPIONs was confirmed by dynamic light scatter and infrared spectrometer, and the contents of iron and polysaccharide were characterized by spectrophotometry. The effect of APS-SPIONs on inducing mouse macrophages RAW264.7 polarization was investigated by flow cytometry. The RAW264.7 macrophages-HepG2 human hepatoma cancer cells Transwell co-culture system was established to investigate APS-SPIONs improve anti-tumor function of macrophages in vitro, and the proliferation activity of APS-SPIONs on RAW264.7 detected by cell counting kit-8 (CCK-8) method. The results showed that the average particle size and zeta potential of APS-SPIONs were (82.93 ± 1.47) nm and (-24.00 ± 0.47) mV. Polysaccharide and Fe content were 8.69% and 7.04%, respectively. APS-SPIONs effectively induced the polarization of RAW264.7 into M1 type in vitro, improving the anti-tumor ability of macrophages in a co-culture system, without effecting the proliferation of macrophages. Our study provides a drug development strategy and preliminary research results to educate macrophages and reshape the tumor immune microenvironment to achieve tumor-killing effects.