Objective:To explore the capability of deep learning image reconstruction (DLIR) compared to adaptive statistical iterative reconstruction (ASiR-V) in improving the image quality and myocardial edge sharpness of dynamic stress myocardial CT perfusion imaging (CTP).Methods:Thirty subjects who underwent dynamic stress myocardial CTP at Guangdong Provincial People′s Hospital from September 2023 to February 2024 were recruited. Image data of all enrolled patients were reconstructed using ASiR-V 50%, ASiR-V 80%, medium-intensity DLIR(DLIR-M), and high-intensity DLIR(DLIR-H), respectively. Regions of interest were selected in the left ventricular cavity, interventricular septum, and left ventricular lateral wall for measurement of CT values and standard deviations (SD), and calculation of signal to noise ratio (SNR) and contrast to noise ratio (CNR). Matlab was utilized to obtain the differences (d) and slopes (s) of CT value changes at four left ventricular myocardial edges for objective edge sharpness evaluation. Two radiologists subjectively scored the images for noise, natural appearance, and edge sharpness. In case of disagreement between the two radiologists, a third senior radiologist′s score was decisive. Left ventricular myocardial blood flow (MBF) of ASiR-V and DLIR images with lower SD, higher SNR and CNR were calculated, respectively. When the normal distribution was satisfied, the independent sample t test was used for comparison between two groups, and the random block design ANOVA was used for comparison between multiple groups. And analysis was conducted using Friedman test for non-normally distributed data, and Bonferroni correction for pairwise comparisons. Results:There were statistically significant differences in SD, SNR, and CNR among the four images in the interventricular septum and left ventricular lateral wall (all P<0.05), with ASiR-V 80% and DLIR-H demonstrating the lowest SD, highest SNR and CNR, and the subjective image noise score. Statistically significant differences were observed in d and s for the four left ventricular myocardial edges (all P<0.05), with DLIR-M and DLIR-H exhibiting the best objective edge sharpness [5 (5, 5)], and ASiR-V 80% the worst [3.5 (3, 4)]. In the subjective scores for natural appearance, DLIR-M and DLIR-H received the highest scores [5 (5, 5)], while ASiR-V 80% received the lowest scores [3 (3, 4)], with statistically significant differences (all P<0.05). There was no statistically significant difference in MBF values calculated from ASiR-V 80% and DLIR-H images (all P>0.05). Conclusions:The SD value, SNR and CNR of dynamic stress myocardial CTP images reconstructed by DLIR-H are equivalent to ASiR-V 80%, and using DLIR-H can improve the edge sharpness of left ventricular myocardium without affecting the calculation of MBF.

Objective:To explore the capability of deep learning image reconstruction (DLIR) compared to adaptive statistical iterative reconstruction (ASiR-V) in improving the image quality and myocardial edge sharpness of dynamic stress myocardial CT perfusion imaging (CTP).Methods:Thirty subjects who underwent dynamic stress myocardial CTP at Guangdong Provincial People′s Hospital from September 2023 to February 2024 were recruited. Image data of all enrolled patients were reconstructed using ASiR-V 50%, ASiR-V 80%, medium-intensity DLIR(DLIR-M), and high-intensity DLIR(DLIR-H), respectively. Regions of interest were selected in the left ventricular cavity, interventricular septum, and left ventricular lateral wall for measurement of CT values and standard deviations (SD), and calculation of signal to noise ratio (SNR) and contrast to noise ratio (CNR). Matlab was utilized to obtain the differences (d) and slopes (s) of CT value changes at four left ventricular myocardial edges for objective edge sharpness evaluation. Two radiologists subjectively scored the images for noise, natural appearance, and edge sharpness. In case of disagreement between the two radiologists, a third senior radiologist′s score was decisive. Left ventricular myocardial blood flow (MBF) of ASiR-V and DLIR images with lower SD, higher SNR and CNR were calculated, respectively. When the normal distribution was satisfied, the independent sample t test was used for comparison between two groups, and the random block design ANOVA was used for comparison between multiple groups. And analysis was conducted using Friedman test for non-normally distributed data, and Bonferroni correction for pairwise comparisons. Results:There were statistically significant differences in SD, SNR, and CNR among the four images in the interventricular septum and left ventricular lateral wall (all P<0.05), with ASiR-V 80% and DLIR-H demonstrating the lowest SD, highest SNR and CNR, and the subjective image noise score. Statistically significant differences were observed in d and s for the four left ventricular myocardial edges (all P<0.05), with DLIR-M and DLIR-H exhibiting the best objective edge sharpness [5 (5, 5)], and ASiR-V 80% the worst [3.5 (3, 4)]. In the subjective scores for natural appearance, DLIR-M and DLIR-H received the highest scores [5 (5, 5)], while ASiR-V 80% received the lowest scores [3 (3, 4)], with statistically significant differences (all P<0.05). There was no statistically significant difference in MBF values calculated from ASiR-V 80% and DLIR-H images (all P>0.05). Conclusions:The SD value, SNR and CNR of dynamic stress myocardial CTP images reconstructed by DLIR-H are equivalent to ASiR-V 80%, and using DLIR-H can improve the edge sharpness of left ventricular myocardium without affecting the calculation of MBF.

【Objective】 To investigate the development of adaptability in children aged 2 - 6, and to explore its influencing factors, so as to provide reference for promoting the development of adaptability in young children. 【Methods】 Data were from the National Nutrition and Health Systematic Survey for Children in China, and 3 319 children aged 2 - 6 and their parents from 28 sites across 14 provinces were recruited in this study.The Development Scale for Children Aged 0 - 6 years (WS/T 580-2017) was used to measure the developmental quotient of children′s adaptive ability, and a survey questionnaire was used to collect relevant information about children and their parents. 【Results】 Among 3 319 children aged 2 - 6, the proportion of slightly low or low level of adaptability, moderate adaptability development, good and excellent adaptability development was 7.68%,66.25% and 26.06%, respectively.The proportion of children aged 5 - 6 with good and excellent adaptability was lower in 3-year-old and 4-year-old groups (χ²=59.29, P<0.05).Multiple stepwise linear regression showed that children′s gender (β=0.06), gestational age of birth (β=-0.05), only child (β=-0.04), left-behind child (β=-0.04), the main caregiver (β=-0.06), and the education level of parents (β=0.09, 0.10), whether parents actively pay attention to children′s emotions (β=-0.06) and whether children play with homemade toys (β=-0.04) were the influencing factors of children′s adaptive development quotient.Girls, full-term children, only children, non-left-behind children, children with parents as main caregivers, parents with a high level of education, parents who often take the initiative to pay attention to children′s emotions, and children who play with homemade toys had a higher level of adaptability development quotient. 【Conclusions】 The development level of adaptability in children aged 2 - 6 in China is mostly above the average level and is related to multiple factors.Targeted intervention work can be carried out on relevant factors in order to promote the development of children′s adaptability.

Cardiovascular disease is the leading cause of death among Chinese residents, and non-invasive imaging technology has important value in the diagnosis and treatment of cardiovascular disease. Cardiac magnetic resonance (CMR) can characterize cardiac pathophysiological information from multiple dimensions, including cardiac structure, function, tissue characteristics, and microstructure, through multi parameter and multi sequence " one-stop" imaging. This article will focus on new technologies such as CMRT1 mapping, feature tracking, and diffusion tensor imaging, and explain their applications and progress in the diagnosis, efficacy monitoring, and prognosis prediction of various myocardial lesions such as non ischemic heart disease and ischemic heart disease.

Objective:To apply cardiovascular magnetic resonance (CMR) to quantitatively evaluate the morphology and tissue characteristics of thoracic skeletal muscle (TSM) in patients with Danon disease and hypertrophic cardiomyopathy (HCM), in order to provide auxiliary differential diagnostic information.Methods:A retrospective study was conducted on 15 Danon disease patients (Danon disease group) who completed CMR examination, and 15 HCM patients (HCM group) and 15 healthy volunteers (control group) who were matched by gender and age were compared. TSM (pectoralis major, pectoralis minor, erector spinae, and subscapularis) area index (TSMAi), T1 relaxation time of four groups, and extracellular volume (ECV) of skeletal muscles of two groups (pectoralis major and subscapularis) were measured for all subjects. Single factor analysis of variance and KruskalWallis test were used to compare three sets of values.Results:The total TSMAi of the Danon disease group was lower than that of the HCM group and the control group [(15.37±3.28)cm 2/m 2 vs (23.02±3.88)cm 2/m 2 vs (22.33±4.67)cm 2/m 2, P<0.001], and the TSMAi of each TSM was also lower than that of the HCM group and the control group (all P<0.05). There was no statistically significant difference in TSMAi between the HCM group and the control group (all P>0.05). The native T1 values of the pectoralis major muscle in the Danon disease group and HCM group were higher than those in the control group (all P<0.05). The ECV of the pectoralis major muscle and subscapularis muscle in the Danon disease group were higher than those in the HCM group and control group, and the enhanced T1 values were lower than those in the HCM group and control group (all P<0.05); There was no statistically significant difference in ECV and the enhanced T1 values between the HCM group and the control group ( P>0.05). Conclusions:The application of CMR can effectively evaluate the changes in TSM morphology and tissue characteristics in Danon disease patients. Compared with HCM patients, Danon disease patients showed significant atrophy of TSM with increased extracellular volume. CMR provides a quantitative reference for TSM in the differential diagnosis of the two.

Objective:To investigate the hemodynamic changes in the ascending aorta (AAo) before and after interventricular septal myocardial resection in obstructive hypertrophic cardiomyopathy (HOCM) using cardiac magnetic resonance four-dimensional blood flow (CMR 4D Flow) technology.Methods:HOCM patients who underwent interventricular septal myocardial resection at Guangdong Provincial People′s Hospital from May 2021 to September 2022 were prospectively included. Age and gender matched healthy volunteers (control group) were included during the same period. Both the control group and HOCM patients underwent CMR examination (including cine sequence and 4D Flow sequence) before and 6 months after surgery. CMR 4D flow technology was used to evaluate changes in AAo preoperative and postoperative blood flow patterns (eddy currents, spiral flow), maximum energy loss (EL max), and average energy loss (EL avg). HOCM patients underwent laboratory tests, including N-terminal pro-brain natriuretic peptide (N-pro BNP) and high-sensitivity troponin T (hsTnT). At the same time, the correlation between postoperative energy loss in HOCM patients and the degree of improvement in laboratory biomarkers was explored. Results:A total of 15 HOCM patients and 15 healthy volunteers were included. (1) In terms of blood flow patterns, the preoperative spiral flow degree of HOCM patients was significantly higher than that of the control group ( P=0.001), but the postoperative difference was not statistically significant ( P=0.059). The degree of eddy currents in HOCM patients before and after surgery was higher than that in the control group (all P<0.05). (2) In terms of energy loss, the preoperative EL max [21.17(14.30-28.10)mW vs 10.17(7.66-13.07)mW, P<0.001] and EL avg [4.87(3.46-5.77)mW vs 2.27(2.19-2.27)mW, P=0.023] of HOCM patients were higher than those of the control group, but there was no statistically significant difference between the postoperative and control groups (all P>0.05). Compared with preoperative, the postoperative EL max [12.33(8.70-17.41)mW] and EL avg [3.10(2.25-4.40)mW] of AAo in HOCM patients were significantly reduced (mean P=0.001). (3) Correlation analysis showed that there was a positive correlation ( r=0.587, P=0.021) between the EL max of AAo and the degree of improvement in hsTNT after interventricular septum myocardial resection, but no significant correlation ( r=0.229, P=0.413) with the degree of improvement in NT-pro BNP. Conclusions:The degree of postoperative AAo blood flow disorder in HOCM patients is reduced, and EL max and EL avg are significantly reduced. The EL max of postoperative AAo is positively correlated with the degree of improvement in hsTNT, suggesting that EL max may be applicable for prognostic evaluation of patients.

Objective To explore the therapeutic effect of lymphatic venous anastomosis based on MRI lymphangiography classifi-cation on lower limb lymphedema,and to analyze the factors affecting the therapeutic effect of lymphatic venous anastomosis.Methods A total of 378 patients with secondary lymphedema of lower limbs were selected.All of them underwent MRI lymphangiography.The differ-ence of circumference diameter and complication rate of the lower limbs of different types of patients before and after lymphatic venous anastomosis were compared.After 6 months of follow-up,the therapeutic effect was evaluated according to the International Lymphology Society classification standards for lymphedema.The risk factors affecting the therapeutic effect of lymphatic venous anastomosis was ana-lyzed,and a prediction model was established to analyze the value of this model in evaluating the clinical efficacy of lymphatic venous anastomosis.Results There was no significant difference in treatment efficiency and postoperative complication rate among different types of patients(P＞0.05).The difference of circumference diameter of the lower limbs of type 3,type 4,type 5 and type 6 before and after treatment was greater than that of type 1,type 2 and type 7(P＜0.05).Age,concomitant infection and lymph node venous fistula were the factors affecting the clinical efficacy of lymphatic venous anastomosis(P＜0.05).The risk prediction model for the clinical efficacy of lymphatic venous anastomo-sis was developed through logistic regression analysis:P=1/[1+e(0.531Xage+0.722Xconcomitant infection+0.807Xlymph node venous fistula-1.249)].The Hosmer-Leme-show test indicated that the fitted model matched the standard curve with x2=2.190,P=0.975.The area under the curve(AUC)of the prediction model for the clinical efficacy of lymphatic venous anastomosis was 0.985,with a standard error(S.E)value of 0.009 and a 95％confidence interval(CI)of 0.967 to 1.000.Conclusion Lymphatic venous anastomosis based on MRI lymphangiography classifi-cation has better clinical efficacy and fewer complications in the treatment of lower limb lymphedema,and the prediction model based on the risk factors analysis has a high predictive value for the clinical efficacy of lymphatic venous anastomosis.

Objective:To prepare a novel 68Ga-labeled bicyclic peptide targeting poliovirus receptor related protein 4 (PVRL4, Nectin-4), and evaluate its feasibility for breast cancer imaging via in vitro and in vivo experiments. Methods:A Biotin-modified bicyclic peptide targeting Nectin-4, Biotin-BMIC, was synthesized, and its targeting properties were preliminarily evaluated by in vitro cell staining experiments. BMIC was modified by 1, 4, 7-triazonane-1, 4-diacetic acid (NODA) and the labeling precursor NODA-BMIC was prepared. A potential PET probe targeting Nectin-4, 68Ga-NODA-BMIC was prepared by one-step labeling strategy. The imaging properties of the probe were investigated by in vivo microPET imaging and in vitro experiments in mice bearing breast tumors. Data were analyzed by independent-sample t test and repeated measures analysis of variance. Results:Fluorescence staining of the cells showed that the fluorescently labeled bicyclic peptide, Biotin-BMIC, was highly aggregated in Nectin-4 positive BT474 breast cancer cells compared to those in Nectin-4 negative MDA-MB-231 cells. The uncorrected yield of 68Ga-NODA-BMIC was (71.5±2.2)% and the radiochemical purity was greater than 95%. The specific activity was greater than 3 GBq/μmol. After incubation 10, 30, 60 and 120 min, higher radioactivity uptakes were found in BT474 breast cancer cells compared to those in MDA-MB-231 breast cancer cells respectively ( F=1 302.00, P<0.001). MicroPET imaging showed that the BT474 xenograft tumors were clearly visible with favorable contrast. A significant statistical difference in uptakes between BT474 and MDA-MB-231 xenograft tumor uptake at 10, 30, 60, and 120 min after probe injection respectively was existed ( F=1 826.00, P<0.001). At 60 min postinjection, the uptake value of BT474 tumors was (5.03±0.14) percentage activity of injection dose per gram of tissue (%ID/g), which was significantly higher than that of MDA-MB-231 tumors ((0.19±0.04) %ID/g; t=79.40, P<0.001). Meanwhile, the tumor-to-muscle ratios in the former were also greater than those in the latter ( F=222.00, P<0.001). At 60 min postinjection, the tumor-to-muscle ratio in the former was significantly higher than that in the latter (24.75±3.10 vs 1.30±0.15; t=14.31, P=0.002). The results were consistent with the immunohistochemistry staining. Conclusions:A novel bicyclic peptide PET probe targeting Nectin-4, 68Ga-NODA-BMIC, is easy to be synthesized and owns satisfactory labeling yield and radiological purity. The imaging performance is good and the target tissues could be visualized. It may play a unique role in the diagnosis and treatment of breast cancer.

Objective : To analyze the status of glucose metabolism in obese children． Methods : 266 cases of obese children were included in the study，fasting plasma glucose ( FPG) ，fasting insulin ( FINS) ，glycosylated hemoglobin ( HbA1c) were measured ，Oral glucose tolerance test ( OGTT) and insulin release test ( IRT) were carried out，insulin resistance index ( HOMA-IR) ，quantified insulin sensitivity index ( QUICKI) and peak insu- lin /fasting insulin (Ip / I0 ) were calculated．Two hundred non-obese healthy children were used as control group， and glucose metabolism indexes were compared between the two groups． Glucose metabolism indexes and the incidence of insulin resistance (IR) were compared in children with different degrees of obesity ．Prediabetes risk factors and body mass index(BMI) correlation were analyzed in obese children. Results : The proportion of predia- betes and type 2 diabetes mellitus in obese children was 18. 0% (48 /266) ．FINS，HOMA-IR and HbA1c in obesi- ty group were higher than those in the control group，but QUICKI was lower than that in the control group (P < 0. 05) ．There was no significant difference in FPG between the two groups (P = 0. 423) ．FINS and HOMA-IR of severe obesity group were higher than those of mild to moderate obesity group，Ip / I0 was lower than that of mild to moderate obesity group (P＜0. 05) ，and there was no significant difference in FPG，QUICKI，HbA1c and 2hPG of severe obesity group．There was no significant difference in IR incidence between mild to moderate obesity group and severe obesity group (P = 0. 163) ．Logistic regression indicated that BMI and acanthosis nigricans was great influential on prediabetes with no statistical significance(P＞0. 05) ．Correlation analysis showed that BMI had no correlation with FPG (P = 0. 160) ，but was positively correlated with FINS，HOMA-IR , 2hPG and HbA1c (P < 0. 05) ，and negatively correlated with QUICKI and Ip / I0 (P＜0. 05) ． Conclusion Abnormal glucose metabolism is available in nearly 20% of obese children．The prevalence of insulin resistance in obese children is not affected by the degree of obesity.

Objective:To understand the agglutination characteristics of different subtypes of avian influenza viruses, we selected erythrocytes from different sources to find suitable erythrocytes for influenza environmental sample detection.Methods:Different subtypes of avian influenza viruses, which were isolated from environmental sample between 2009 and 2016 in China, were selected to do hemagglutination assay using 5 animal erythrocytes (chicken, turkey, guinea pig, horse, and sheep). Flow cytometry was used to detect expression level and type of sialic acid receptors of different erythrocytes, and the characteristics of the receptor binding domain (RBD) of the viral hemagglutinin protein were analyzed by amino acid sequence.Results:In this study, a total of 28 strains of avian influenza virus including 14 subtypes were detected. The result showed that all viruses could agglutinate with turkey and guinea pig erythrocytes and the rest three erythrocytes were unable to produce agglutination with some viruses; among them, one H9N2 virus (A/environment/Anhui/43762/2015) did not agglutinate with chicken erythrocytes, one H1N1 virus (A/environment/Shandong/76972/2014) and two H9N2 viruses (A/environment/Chongqing/79449/2014 and A/environment/Anhui/43762/2015) did not agglutinate with horse erythrocytes, two viruses of H9N2 (A/environment/Chongqing/79449/2014 and A/environment/Anhui/43762/2015) and two viruses of H13N8 (A/environment/Qinghai Lake/166/2012 and A/environment/Qinghai Lake/13/2012) did not agglutinate with sheep erythrocytes. The result of flow cytometry showed that two sialic acid receptors, α-2, 3 and α-2, 6, were detected on the surface of erythrocytes of turkey, chicken and guinea pig, but the expression ratios of the two receptors were different. Only the expression of α-2, 3 sialic acid receptors was detected in horse and sheep erythrocytes. Sequence analysis suggested that amino acid substitution in key regions of viral hemagglutinin protein RBD may be an important factor affecting the binding properties of different erythrocytes.Conclusions:Our result suggested that turkey and guinea pig erythrocytes are the most sensitive in the hemagglutination test. Receptor expression and type of erythrocytes from different sources can significantly affect the agglutination reaction of different subtypes of avian influenza virus, and the amino acid changes in key regions of RBD can also affect the result of agglutination reaction.