Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective To investigate the value of color Doppler ultrasonography in mammary ductal ectasia( MDE). Methods Preoperative sonograms of 54 MDE,135 invasive ductal carcinoma( IDC) and 68 ductal carcinoma in situ ( DCIS ) patients were retrospectively analyzed and further confirmed by histopathology. Results MDE showed 88.9% (48/54) mass type and 11.1% (6/54) ductal type.The average age of patients in MDE was younger than that in IDC( P ＜0.05). The number of MDE located around the areola was more than that of IDC( P ＜0.05). Mean maximum diameter of MDE was smaller than that of DCIS ( P ＜0.05). Compared to DCIS and IDC,MDE in mass type showed higher detection rate of liquidity area and mammary ductal ectasia( all P ＜0.05),while lower detection rate of hyperecho, peripheral hyperechoic zone,posterior echo attenuation or blood flow richness( all P ＜0.001). Compared to IDC,MDE in mass type showed higher detection rate of inside ductal echolocation,while showed lower detection rate of irregular shape,spiculate margin or axillary lymph node enlargement. Compared to DCIS, MDE showed higher detection rate of large aspect ratios( ≥0.7). Less MDE in ductal type with hyperecho were found than DCIS in ductal type ( P ＜ 0.001 ). The coincidence rate of ultrasonic diagnosis and postoperative histopathhology results in 54 MDE patientis was 13.0% ( 7/54 ). Conclusions The sonographic findings of MDE has diverse manifestations. It shows important value of ultrasonography for MDE in its diagnosis and differential diagnosis with breast cancer.

Objective To investigate the correlation between the features of conventional ultrasound& shear wave elasticity and axillary lymph node involvement in breast cancer . Methods A total of 169 breast cancers patients were divided into lymph node metastasis group( n = 115) and non metastasis group ( n = 54 ) according to the postoperative pathological results . Preoperative conventional ultrasonographic features and preoperative shear wave elastography quantitative parameters ( E values ) of the two groups breast lessons were analyzed by single factor analysis to screen out statistically significant factors ,then Logistic regression analysis was performed to analyze the relationship between above factors and lymph node involvement . Results Single factor analysis showed the microcalcification and hyperechoic halo detection rates of lymph node metastasis group [ 81 .7％ ( 94/115) and 71 .3％ ( 82/115 ) ,respectively] were higher than those in non metastasis group [ 61 .1％ (33/54) and 50 .0％ ( 27/54) ,respectively] . The elastography maximum value( Emax) of lymph node involvement group was ( 182 .2 ± 74 .0) kPa ,which was larger than that in non metastasis group′s ( 153 .3 ± 76 .9) kPa ( P < 0 .05) . Multivariate Logistic regression analysis showed the microcalcification( OR = 2 .498 , P = 0 .022) ,the hyperechoic halo( OR = 2 .482 , P = 0 .013) and the Emax value( OR = 1 .007 , P = 0 .007) were risk factors of axillary lymph node metastasis in breast cancer . Conclusions Breast cancer with microcalcification ,hyperechoic signs and high Emax value is more likely to develop axillary lymph node metastasis .

Objective To explore the value of the cavum vergae vanishing sign for prenatal ultrasound diagnosis of fetal agenesis of the corpus callosum ( ACC ) . Methods Fifty-one cases of ACC of 20 - 32 gestational weeks were confirmed by MRI or induced fetal autopsy . A random selection of 80 normal fetuses of 20 - 32 gestational weeks were chosed as control group . The displays of the cavum septum pellucidum ( CSP) and the cavum vergae( CV ) in the two groups were observed . Results There were 36 cases of complete agenesis of the corpus callosum ( CACC) and 15 cases of partial agenesis of the corpus callusom ( PACC) in ACC group . In 51 ACC cases ,43 cases were confirmed by prenatal MRI ,while 8 cases were confirmed by postnatal MRI . The comparison of display of CSP and CV between the ACC group and the health group was as follows : ① CSP vanishing rate in ACC group was 70 .6％ ( 36/51 ) ,meanwhile the disappearance rate of CSP in the health group was 0 ( 0/80 ) ,the difference between the two groups was statistically significant( χ2 = 77 .870 , P = 0 .000) . ② CV vanishing rate in ACC group was 96 .1％ (49/51) , meanwhile the disappearance rate of CV in the health group was 1 .2％ ( 1/80) ,the difference between the two groups was statistically significant ( χ2 = 118 .673 , P = 0 .000) . The correlation coefficient between the CV vanishing sign and the occurrence of ACC was 0 .952 ( P = 0 .000) ,while the correlation coefficient between the CSP vanishing sign and the occurrence of ACC was 0 .771 ( P = 0 .000) . There were significant differences in CSP disappearance rate and CV disappearance rate between ACC group and control group at different gestational weeks ( 20 - 24 weeks ,25 - 28 weeks and 29 - 32 weeks) ( all P < 0 .001) . Conclusions The cavum vergae vanishing sign ,as an important indirect sign of fetal agenesis of the corpus callosum ,can be obtained quickly from horizontal transverse section of the cavum septum pellucidum . During the middle pregnancy ,it could be an important prenatal ultrasound screening clue for fetal agenesis of the corpus callosum .

Purpose To explore ultrasonic characteristics of complex fibroadenoma (CF) of breast and its differential diagnosis from invasive ductal carcinoma (IDC).Materials and Methods Sixty-one patients with CF and 81 patients with IDC from January 2010 to February 2016 in the Affiliated Union Hospital of Fujian Medical University were enrolled,and the CF and IDC were confirmed by pathology after operation.The preoperative sonographic findings of CF and IDC were retrospectively analyzed and compared.Results Fifty-nine cases with CF were detected by ultrasonography in 61 cases.Ultrasonic findings of 59 cases of CF showed as follows:79.7％ (47/59) of the CF cases with an aspect ratio ＜0.7;79.7％ (47/59) with blood flow signal of 0 to 1 level;72.9％ (43/59) with liquid dark area,including 67.8％ (40/59) with round or oval cystic fluid area showing local sievelike or diffused distribution;72.9％ (43/59) with irregular shape;61.0％ (36/59) with obscure boundary;61.0％ (36/59) with the largest diameter of tumor ＜2 cm;59.3％ (35/59) with calcifications,including 33.9％ (20/59) with coarse calcification,25.4％ (15/59) with microcalcification and 85.7％ (30/35) with distribution of calcified lesions along the linear high echo zone;54.2％ (32/59) with echo heterogenicity showing linear high echo and high echo in the middle and low echo.There were significant differences in the detection rates of internal regular fluid area,internal linear high echo or high echo area,and alcification distribution along the linear high echo between CF and IDC lesions (all P＜0.01).Compared with IDC,there were higher rates in CF for detecting lesions of largest diameter of tumor ＜2 cm,more regular shape,more clear border,poorer blood flow signal (P＜0.05),but there were lower rates in CF for detecting axillary lymph node enlargement,lesions with edge or spiculation and hyperechoic halo (P＜0.01).Conclusion Color Doppler ultrasonography is of great value in the diagnosis of CF and its differential diagnosis from IDC.

Objective To investigate ultrasonic findings of pure invasive micropapillary carcinoma (PIMPC) of breast. Methods A total of 18 patients with surgically confirmed PIMPC and 40 patients with surgically confirmed invasive ductal carcinoma (IDC) treated between January 2010 and August 2015 in Affiliated Union Hospital of Fujian Medical University, who had undergone preoperative ultrasound examination, were included in the study. To compared with the postoperative pathological examination, the value of ultrasonography in the diagnosis of axillary lymph node metastasis was discussed.Ultrasound findings of PIMPC and pathological results were compared. Results Ultrasound analysis of PIMPC masses identified predominantly hypoechoic lesions and irregular shape 100% (18/18), obscure lesion boundaries 88.9% (16/18), spiculated or angular margins 83.3% (15/18), combined microcalcifications 83.3% (15/18), with posterior acoustic enhancement or normal 88.9% (16/18), dcrab claws changes 77.7% (14/18),witout hyperechoic halo72.2% (13/18) and with 0- Ⅰ grade flow signals 55.6% (10/18). Compared to the IDC, the PIMPC had lower proportions in long speculation, hyperechoic halo, aspect ratio ≥ 0.7, posterior echo attenuation, Ⅱ- Ⅲ grade blood flow signals (P < 0.05), while their lesions in the maximal tumor size,shape, boundary, edge bur, microcalcification has no significance (P>0.05). The rate of lymph node metastasis of PIMPC was 72.2% (13/18), which was significantly higher than that of IDC 45.0% (18/40) (t=3.697,P=0.05). 13 cases were pathologically confirmed lymph nodes metastasis in 18 cases, and among them, the ultrasound indicated abnormal 46.2% (6/13), and showed abnormal cortex and medulla structure 30.8% (4/13), eccentric lymph door 30.8% (4/13), poor blood flow signals 38.5% (5/13). The sensitivity, specificity,positive predictive value, negative predictive value and accuracy of PIMPC lymph node metastasis by preoperative ultrasound were respectively 46.2%, 60.0%, 75.0%, 30.0%, 50.0%. Ultrasound performance of PIMPC has a certain relationship with its special pathological characteristics. Sonography findings were compared with pathological results: Microscopically, PIMPC cell arranged as pseudo-papillary or tubuloalveolar structures floating in empty spaces; PIMPC with 0-Ⅰ grade flow signals were seen that the small amount of new blood vessels of the tumor were mainly found in the pellucid zone around the cell clusters under the microscope, while IDC with Ⅱ - Ⅲ grade blood flow signals were found that more regenerated blood vessels were distributed in the collagen fibers. PIMPC witout hyperechoic halo were noticed that under the microscope, there were no fibrous tissue clusters in the edge of the tumor, meanwhile, IDC with hyperechoic halo were discovered that fibrous tissue was seen at the edge of the mass of the lens. Conclusions Ultrasound performance of PIMPC has a close relationship with its special pathological characteristics. To be familiar with ultrasound characteristic of PIMPC is significant for improving its ultrasound detection rate.

Objective To investigate the relationship between RKIP expression and the efficiency of radiotherapy in NPC patients and evaluate the possibility of using RKIP as a predictor of radiosensitivity.Methods A total of 180 patients with NPC in Sun Yat-sen University Cancer Center without evidence of distant metastasis at initial diagnosis were enrolled in this study,who had received intensity-modulated radiotherapy alone.Patients were classified into 2 groups according to criteria below:patients with biopsy proven recurrent diseases occurring at nasopharynx and/or neck within 5 years after radiotherapy were classified as the radioresistant group.The pathological type at relapse was the same as the previous one before treatment.Patients with a minimum follow-up of 5 years after radiotherapy without evidence of recurrence at the original site of the tumor were classified as the radiosensitive group.Patients in the 2 groups were matched according to the factors related with radiosensitivity.RKIP was examined by immunohistochemical staining before radiotherapy.The relationship between RKIP expression and the effect of radiotherapy were analyzed.Results The positive rate of the RKIP expression in the radiosensitive group versus the radioresistant group was 80.0％ versus 26.7％.The positive rate (x2 =12.498,P ＜0.01) and the intensity of the RKIP expression (x2 =51.429,P ＜ 0.01) were significantly different between 2 groups with a negative correlation with radio-resistance to NPC (r =-0.344,-0.535,respectively,P ＜ 0.01).Based on the RKIP expression,the radiosensitivity,specificity,accuracy,positive predictive value,negative predictive value,false positive and false negative were predicted as follows:80.0％,73.3％,77.2％,75.0％,78.6％,26.7％,and 20.0％,respectively.Conclusions RKIP protein shows negative correlation with radioresistance to NPC and could serve as a biomarker in preliminarily screening the intrinsic radiosensitivity of NPC.

Objective To discuss the feasibility of Monte Carlo N-particle transport code(MCNP)simulated calculation.Methods The calculation in water phantom was contrasted with the practical measurements and the reported values using the percent depth dose(PDD)curve and normal peak scatter factor.Results There Was no significant difference between calculated and measured results in the 10 cm×10 cm field(t＝-0.41,P>0.05),however,there were significant differences in the 5 cm×5 cm field(t=7.2,P<0.05)and in the 12 cm×12 cm field(t=-4.6,P<0.05).There was no significant difierence between the calculated results and the reported values(t=-1.91,P>0.05).In the same radiation field,the PDD decreased as the depth increased,but increased as the size of the radiation field increased at the same depth.PDD and normal peak scatter factor were both important parameters for calculation of prescribed dose.Conclusions It is possible to establish a set of accurate and comprehensive percent depth doses and normal peak scatter factor parameters so as to provide the basis of clinical use, quality assurance and quality control for radiotherapy.