The most radiation exposure for children arises from the medical process, and due to their characteristics such as relatively immature,organ development,they are more sensitive to the radiation than a-dults,and have higher risk of radiation related diseases,so medical radiation exposure should not be ignored.

Objective To study the initial and the follow-up manifestations of infants with Langerhans’ cell histiocytosis (LCH) and evaluate the relationship between X-ray manifestations and clinical prognosis. Methods The radiological manifestations were analysed in 22 cases of LCH proved by clinical features, laboratory data, and pathology. According to Lavin’s Grade, the 22 cases were classified as Grade I (9 cases), Grade II (9 cases), and Grade III (4 cases). Plain radiography was performed in all cases during the initial and the follow-up,including cranial bones, chest, long bones, and spine. CT was performed in 12 cases. Results Of the 22 cases, there were 7 cases which lesions were limited to bones. 5 of them were demonstrated with ossification and remodeling of the involved bone after chemotherapy.The remaining 15 cases were associated with multi-systemic involvements, only 4 of which improved after chemotherapy. Among these 15 cases, 7 had lung involvement, only 2 of which had gotten better. Hypothalamus/pituitary axis was affected in 1 case. Conclusion The extension of the bone involvement can reflect LCH clinical prognosis. However,the lung involvement of LCH, which mainly presented with interstitial lesion, is not sensitive for the evaluation of clinical situation.LCH with limited bone destructions have a better prognosis than those with the multi-systemic involvements.

Objective To analyze imaging findings of IPH and to study the correlation between the HRCT findings and the pulmonary function of IPH.Methods The information of 15 children with IPH were reviewed.Results The X-ray findings of IPH included ground glass opacity(n=9),exudative shadows(n=10),reticulonodular shadows(n=7),nodular shadows(n=6).The HRCT signs included abnormal bronchovascular bundles(n=12),ground glass opacity(n=12),exudative shadows ( n=11 ) ,disseminated micronodular shadows ( n=8 ) , thickened pulmonary lobular septa ( n=9 ) . The correlation between ground glass opacity and pulmonary function was 0.5394 ( P=0.134); The correlation between thickened pulmonary lobular septa and the pulmonary function was 0.9963(P=0.0001).Conclusion The HRCT examination is better than the X-ray examination. The positive correlation between thickened pulmonary lobular septa and pulmonary function change is significant,it is beneficial to estimate the damage of the palmonary.

Objective:To study the effects of ~(125)I-(α_v)ASODN on the in vitro invasive ability of heptocellular carcino-ma cell line(HepG2) through PEI-RGD-mediated receptor process. Methods: Intergrin α_v-specific antisense oligonucle-otide was labeled with ~(125)I, and PEI-RGD/~(125)I-(α_v)ASODN complex was prepared by combining ~(125)I-(α_v)ASODN with polyethyleneimine derivative PEI-RGD. PEI-RGD/~(125)I-(α_v)ASODN complex was transferred into HepG2 cells through the receptor-mediated process. The effect of PEI-RGD/~(125)I-(α_v)ASODN complex on the invasive ability of HepG2 cells was examined by Boyden chamber invasive assay. Results: (1) The labeling yield and radiochemical purity of ~(125)I-(α_v) ASODN were(73.78±4.09)% and(96.68±1.38)%, respectively, and the labeled compound had a good stability in vitro after 48 h at 37℃; (2) The ability of HepG2 cells to uptake PEI-RGD/~(125)I-(α_v)ASODN reached its peek ([12.77±0.85] % ) when PEI-RGD/~(125)I-(α_v)ASODN was at 4 μl/2 μg ([12.77±0.85] %), and then gredually decreased thereafter. So the dosage of PEI-RGD/~(125)I-(α_v)ASODN for the following experiment was chosen as 2 μl/1 μg; (3) The invasive capacity of HepG2 cells was significantly reduced in PEI-RGD/~(125)I-(α_v)ASODN group compared with those in other experiment and control groups (P <0.01 ). Conclusion: ~(125)I-(α_v)ASODN mediated by PEI-RGD can effectively inhibit the invasive capacity of HepG2 cells.

Objective To analyze the imaging characteristics of hepatic involvement in Langerhans cell histiocytosis(LCH) in children on MRCP, MRI and CT. Methods Twenty-nine children from three children hospitals in China, who were diagnosed as hepatic involvement by disseminated LCH during Aug 2008 and Jan 2015 were included in this study. Their MRCP (n=16), MRI (n=22), contrast?enhanced CT (n=15) data were retrospectively analyzed. The stenoses and dilatation of the intrahepatic bile ducts, the common hepatic bile duct and its first order branches and the common bile duct were evaluated on the MRCP image. The size and shape of the liver, the imaging characteristics of the periportal lesions in the Glisson sheath and hepatic parenchymal lesions were also evaluated on the cross?sectional images. Results MRCP indicated alternative stenoses/dilatation of the bile duct tree (n=16), stenoses of the common hepatic duct and its first?order branches (n=15), partialindistinctness of the common bile duct (n=2) and multiple cystic lesions along the biliary tree (n=5). On the cross?sectional images, the periportal lesions in the Glisson sheath were observed in 28 children. On MRI, the periportal lesions were shown in all the 22 children with MRI, presented as hypo-signal intensity on T1WI, hyper?signal intensity on T2WI (n=11) or mixed?signal intensity on T1WI and T2WI (n=11); On CT, the periportal lesions were found in 14 of the 15 children with CT, presenting as low density (n=13) and mixed density (n=1). Multiple nodular or cyst?like parenchymal lesions were observed in 21 patients including 18 patients on MRI and 5 patients on enhanced CT. Sixteen patients presented as hypo?intensity on T1WI, hyper?intensity on T2WI and low density on plain CT, and 5 patients with iso? or hypo?intensity on T1WI, hypo?intensity on T2WI,and milder enhancement relative to the adjacent parenchyma on contrast?enhanced CT. Conclusions The imaging characteristics of hepatic involvement by LCH include alternative stenoses and dilatation of the intrahepatic ducts, stenoses of the common hepatic bile duct and its first?order branches on MRCP, the periportal lesions in the Glisson sheath and hepatic parenchymal nodular or cyst?like lesions on cross?sectional images.

Objective To identify the clinical and imaging characteristics in neonatal refractory purulent meningitis. Methods Clinical data of 70 cases of neonatal purulent meningitis admitted to the neonatal intensive care unit at Children's Hospital of Fudan University from January, 2009 to December, 2014 were reviewed retrospectively. The patients were divided into refractory group (n=28) and non-refractory group (n=42) according to the course of antimicrobial therapy.The clinical and brain MRI characteristics of neonatal refractory purulent meningitis were analyzed. Parameters were compared between the two groups using Chi-square or Fisher's exact tests, and Wilcoxon tests where appropriate. Risk factors of neonatal refractory purulent meningitis were investigated by univariate and multivariate Logistic regression analysis. Results Among the 70 cases, 31(44.3%) were positive for cerebrospinal fluid (CSF)/blood culture. The positive rate was higher in the refractory group than in the non-refractory group [75.0%(21/28) vs 23.8%(10/42),χ2=17.843, P<0.01]. The most common pathogenic bacteria isolated in the refractory group were Escherichia coli [8 cases (38.1%)] and group B streptococci [5 cases (23.8%)]. Compared to the non-refractory group, patients in the refractory group were more likely to have seizure, higher CSF white blood cell count, higher CSF protein concentration and lower CSF glucose concentration [53.6%(15/28) vs 7.1% (3/42), 965.0 (463.0-2 200.0)×106/L vs 116.5 (61.0-327.5)×106/L, 3 221.1(2 354.3-4 633.5) mg/L vs 1 487.6(988.2-1 924.1) mg/L, and 0.2 (0.1-0.8) mmol/L vs 1.5 (1.2-1.8) mmol/L; all P<0.01]. Multivariate Logistic regression analysis showed that seizure, low CSF glucose concentration on admission, and a positive CSF/blood culture result neonatal refractory purulent meningitis (OR=9.6, 95%CI: 1.2-76.0; OR=15.0, 95%CI: 5.6-63.3; and OR=7.3, 95%CI: 1.5-36.0, respectively). Abnormal brain MRI findings, including intracranial extracerebral space abnormality, ventricular dilatation and periventricular white matter injury, were more common in the refractory group [100.0%(28/28) vs 61.9%(26/42), χ2=13.827 totally; 64.3%(18/28) vs 21.4%(9/42), χ2=13.023 for intracranial extracerebral space abnormality; 60.7%(17/28) vs 19.0%(8/42), χ2=12.704 for ventricular dilation and 28.6%(8/28) vs 2.4%(1/42) for periventricular white matter injury; all P <0.01]. Compared with the non-refractory group, the refractory group had a longer hospital stay [(48.0±17.4) d vs (26.0±10.2) d, t=6.016, P<0.01] and more adverse events [67.9%(19/28) vs 31.0%(13/42), χ2=9.220, P=0.002], including hearing impairment and requirement of neurosurgical intervention [14/18 ears vs 10/46 ears (21.7%), χ2=4.292, P=0.038]. There was no death in both groups during hospitalization. Conclusions Neonates with seizure, low CSF glucose concentration and positive CSF/blood culture results are more likely to have refractory purulent meningitis. Brain MRI abnormalities are more common in neonatal refractory purulent meningitis.

Objective: To analyze the expression and clinical significance of solute carrier family 5 member 5 (SLC5A5), the coding gene of sodium/iodide symporter (NIS), in thyroid carcinoma. Methods: The messenger RNA (mRNA) expression of SLC5A5 in thyroid carcinoma and normal thyroid tissues from The Cancer Genome Atlas (TCGA) was compared using independent-sample t test and results were shown in one scatter plot. The relation between clinical features of thyroid carcinoma and the changes of SLC5A5 mRNA was analyzed on LinkedOmics using Kruskal-Wallis test or Wilcoxon test. Results: Data from TCGA showed that the SLC5A5 mRNA expression in thyroid carcinoma (1.419±0.049) was significantly reduced compared with that in normal thyroid tissues (3.301±0.087; t=12.66, P<0.01). The expression of SLC5A5 mRNA in thyroid carcinoma is affected by ethnicity (χ²=0.300, P<0.05). Moreover, the expression of SLC5A5 mRNA were decreased with the increase of pathologic grading (Ⅰ, Ⅱ, Ⅲ, Ⅳ) and T, N, M stages (χ² values: 0.114, 0.215, z values: -0.345, -0.102, all P<0.05). Conclusions The expression level of SLC5A5 mRNA is associated with clinical characteristic of thyroid carcinoma. SLC5A5 mRNA has the potential to become one candidate biomarker to assess disease and predict the development of thyroid carcinoma.

In order to discriminate normal and abnormal heart sounds accurately and effectively, a new method is proposed to analyze heart sounds, namely heart sound characteristic waveform (HSCW) method. Digital stethoscope is used to collect heart sound signals. The recorded data are transmitted to a computer by USB interface for analysis based on HSCW, which is extracted from an analytical model of single degree-of-freedom (SDOF). Furthermore, a case study on the normal and abnormal cardiac sounds is demonstrated to validate the usefulness and efficiency of the proposed HSCW method. Besides, in order to test the accuracy of discriminating normal and abnormal heart sounds, 40 normal and 20 abnormal heart sounds are collected and analyzed, the accuracy performances are achieved by 92.5% and 95.0%, respectively.
Algorithms ; Heart Auscultation ; instrumentation ; methods ; Heart Sounds ; physiology ; Humans ; Phonocardiography ; methods ; Signal Processing, Computer-Assisted

Objective To evaluate the role of multi-slice CT (MSCT) perfusion in early diagnosis of liver fibrosis. Methods Thirty-three subjects underwent CT perfusion of the liver. Among whom, 11 subjects were volunteers without hepatic disease and the other 22 subjects were pathologically confirmed with liver fibrosis who were further divided into slight (n= 10) and severe (n=12)liver fibrosis according to the lshak system. Parameters of CT perfusion were measured and compared among three groups. Results The mean hepatic arterial fraction in controls, light and severe fibrosis tended to increase with the severity of liver fibrosis[(18. 49 ± 9. 69) %, (19. 92 ± 6.01) % and (21.31±7.47)% ,respectively], and the mean mean transit time tended to decrease with the severity of liver fibrosis [(13.80 ± 2. 60) s, (12.35 ± 1.31) s and (12.19 ± 3.33) s, there was no significant difference in all parameters between any two groups (P>0.05). Conclusions Quantitative measurement of hepatic blood supply can be obtained by CT perfusion. Some parameters will be helpful in staging fibrosis to a certain extent. But its clinical usefulness for the evaluation of the early diagnosis may not be affirmed yet.

Objective To evaluate aorta's compliance after repair of coarctation of the aorta (CoA)using the pulse wave velocity (PWV)of MRI.Methods A retrospective analysis of cardiac MR images in 22 patients after repair of CoA was performed.PWV was measured and calculated with phase contrast MRI,and echocardiography was performed to measure both ventricular function and myocardial thickness during the same period.Age and sex-matched 22 normal subjects were served as a control group and their aortic PWVs were measured.Results The averaged PWV in study group was significantly higher than that in control group [(4 .42 ± 3 .02 )m/s vs (2 .73 ± 0 .76 )m/s,P =0.02].In study group,the PWV value of children with moderate anastomotic stenosis was the highest. ROC curve analysis showed the highest sensitivity and specificity could be achieved to distinguish the mild or moderate anastomotic stenosis when the threshold for PWV was 3.37 m/s.No significant correlations were found between left ventricular end-diastolic volume,left ventricular end-systolic volume,ejection fraction,left ventricular thickness and PWV.Conclusion PWV is increased in children after repair of CoA.Significant aortic remodelling can be observed in patients with moderate anastomotic stenosis.