Multitask deep learning for prediction of microvascular invasion and recurrence-free survival in hepatocellular carcinoma based on MRI images.

BACKGROUND AND AIMS: Accurate preoperative prediction of microvascular invasion (MVI) and recurrence-free survival (RFS) is vital for personalised hepatocellular carcinoma (HCC) management. We developed a multitask deep learning model to predict MVI and RFS using preoperative MRI scans. METHODS: Utilising a retrospective dataset of 725 HCC patients from seven institutions, we developed and validated a multitask deep learning model focused on predicting MVI and RFS. The model employs a transformer architecture to extract critical features from preoperative MRI scans. It was trained on a set of 234 patients and internally validated on a set of 58 patients. External validation was performed using three independent sets (n = 212, 111, 110). RESULTS: The multitask deep learning model yielded high MVI prediction accuracy, with AUC values of 0.918 for the training set and 0.800 for the internal test set. In external test sets, AUC values were 0.837, 0.815 and 0.800. Radiologists' sensitivity and inter-rater agreement for MVI prediction improved significantly when integrated with the model. For RFS, the model achieved C-index values of 0.763 in the training set and ranged between 0.628 and 0.728 in external test sets. Notably, PA-TACE improved RFS only in patients predicted to have high MVI risk and low survival scores (p < .001). CONCLUSIONS: Our deep learning model allows accurate MVI and survival prediction in HCC patients. Prospective studies are warranted to assess the clinical utility of this model in guiding personalised treatment in conjunction with clinical criteria.

Anti-MDA5 antibody dermatomyositis-associated rapidly progressive interstitial lung disease patient complicated with mixed connective tissue disease: A case report.

Anti-MDA5 antibody dermatomyositis (DM) is a special type of myositis, which can potentially cause rapidly progressive interstitial lung disease (RP-ILD). Mixed connective tissue disease (MCTD) is a complex disease with different characteristics of autoimmune connective tissue disease, associated with ILD. Both are rare diseases, and few patients with both diseases have been reported. A 71-year-old woman complained of palpitations, with a 2 months history of rash around her hands, extensor surface of right elbow, and the nape of her neck. Subsequently, the patient had acute exacerbation of dyspnea and tachypnea. Anti-Ro52, U1 RNP and MDA5 antibodies were positive; the presenting evidence was suggestive of anti-MDA5+ DM-RP-ILD complicated with MCTD. Our patient deteriorated rapidly and had a fatal outcome, despite "triple therapy" for RP-ILD. This case illustrates that patients with coexisting anti-MDA5+ DM and MCTD have the former's typical clinical manifestations, and may develop ILD quickly rather than slowly as in MCTD, especially with the coexistence of anti-Ro52 antibodies.

Correlation between Mycoplasma pneumoniae drug resistance and clinical characteristics in bronchoalveolar lavage fluid of children with refractory Mycoplasma pneumoniae pneumonia.

BACKGROUND: To investigate the resistance-gene mutation of Mycoplasma pneumoniae (MP) in the bronchoalveolar lavage fluid of children with Mycoplasma pneumoniae pneumonia (MPP) and the clinical characteristics of refractory Mycoplasma pneumoniae pneumonia (RMPP) correlation. METHODS: Forty-eight children with MPP were selected and placed in RMPP and non-RMPP groups based on their clinical status - whether they had worsening clinical symptoms, persistent fever and a worsening lung image. They were also separated into drug-resistance gene mutation and non-mutated groups using nucleic acid detection. The participants' data were collected on high-sensitivity C-reactive protein and MP-DNA loads, fever time, hospitalisation time, macrolide antibiotic application time and fever regression time after application. The differences in imaging manifestations were determined by using multivariate logistic regression to analyse the clinical characteristics of RMPP. Additionally, the correlation between drug-resistance gene mutations and the clinical characteristics of RMPP was summarised. RESULTS: Among the 48 MPP children, 31 (64.6%) had A2063G and/or A2064G gene mutation, 31 (64.6%) had RMPP and 23 (74.2%) had drug-resistance gene mutation. The children in the drug-resistance gene mutation group had higher high-sensitivity C-reactive protein and MP-DNA loads, longer fever time, hospitalisation time, macrolide antibiotic application time, fever regression time after application and extrapulmonary complications. There were more symptoms and more severe changes under bronchoscopy. The difference was statistically significant (P < 0.05). Logistic multivariate regression analysis showed that the mutation of drug-resistance genes had no significant correlation with RMPP. CONCLUSION: The mutation rate of drug-resistance genes in children with MPP is high, the inflammatory index and MP-DNA load are high, the course of the disease is long, and the changes under bronchoscopy are severe. The occurrence of RMPP is not only determined by drug-resistance genes but may also be the result of a combination of factors.

Association between pulmonary hemorrhage and CPAP failure in very preterm infants.

Background: Pulmonary hemorrhage (PH) in neonates is a life-threatening respiratory complication. We aimed to analyze the perinatal risk factors and morbidity with PH among very preterm infants in a large multicenter study. Methods: This was a multicenter case-control study based on a prospective cohort. Participants included 3,680 in-born infants with a gestational age at 24-32 weeks (birth weight <1,500 g) who were admitted between January 1, 2019, and October 31, 2021. All infants were divided into two groups, namely, the PH and no-PH groups, at a ratio of 1:2 according to the following factors: gestational age (GA), birth weight (BW), and the Score for Neonatal Acute Physiology with Perinatal extension II (SNAPPE II). Perinatal factors and outcomes were compared between the two groups by logistic regression analyses. Results: A total of 3,680 infants were included in the study, and the number of identified cases of PH was 262 (7.1%). The incidence was 16.9% (136/806) for neonates with extremely low BW (BW < 1,000 g) infants. The multivariate analysis showed that CPAP failure (OR 2.83, 95% CI 1.57, 5.08) was significantly associated with PH. PH was associated with a high likelihood of death (OR 3.81, 95% CI 2.67, 5.43) and bronchopulmonary dysplasia (BPD) (≥grade II) (OR 1.58, 95% CI 1.00, 2.48). Conclusions: In this multicenter case-control study based on a prospective cohort, PH to be common among VLBW infants. PH is associated with significant morbidity and mortality, and perinatal management, especially CPAP failure. Respiratory management strategies to decrease the risk of PH should be optimized.

Reduced CircSMOC1 Level Promotes Metabolic Reprogramming via PTBP1 (Polypyrimidine Tract-Binding Protein) and miR-329-3p in Pulmonary Arterial Hypertension Rats.

BACKGROUND: Pulmonary arterial hypertension maintains rapid cell proliferation and vascular remodeling through metabolic reprogramming. Recent studies suggested that circRNAs play important role in pulmonary vascular remodeling and pulmonary arterial smooth muscle cells proliferation. However, the relationship between circRNA, cell proliferation, and metabolic reprogramming in pulmonary arterial hypertension has not been investigated. METHODS: RNA-seq and qRT-PCR reveal the differential expression profile of circRNA in pulmonary arteries of pulmonary arterial hypertension rat models. Transfection was used to examine the effects of circSMOC1 on pulmonary artery smooth muscle cells, and the roles of circSMOC1 in vivo were investigated by adenoassociated virus. Mass spectrometry, RNA pull-down, RNA immunoprecipitation, and dual-luciferase reporter assay were performed to investigate the signaling pathway of circSMOC1 regulating the metabolic reprogramming. RESULTS: CircSMOC1 was significantly downregulated in pulmonary arteries of pulmonary arterial hypertension rats. CircSMOC1 knockdown promoted proliferation and migration and enhanced aerobic glycolysis of pulmonary artery smooth muscle cells. CircSMOC1 overexpression in vivo alleviates pulmonary vascular remodeling, right ventricular pressure, and right heart hypertrophy. In the nucleus, circSMOC1 directly binds to PTBP1 (polypyrimidine tract-binding protein), competitively inhibits the specific splicing of PKM (pyruvate kinase M) premRNA, resulting in the upregulation of PKM2 (pyruvate kinase M2), the key enzyme of aerobic glycolysis, to enhance glycolysis. In the cytoplasm, circSMOC1 acted as a miR-329-3p sponge, and its reduction in pulmonary arterial hypertension suppressed PDHB (pyruvate dehydrogenase E1 subunit beta) expression, leading to the impairment of mitochondrial oxidative phosphorylation. CONCLUSIONS: circSMOC1 is crucially involved in the metabolic reprogramming of pulmonary artery smooth muscle cells through PTBP1 and miR-329-3p to regulate pulmonary vascular remodeling in pulmonary arterial hypertension.

Interaction between CASP8AP2 and ZEB2-CtBP2 Regulates the Expression of LEF1.

Low expression of CTBP2 and CASP8AP2 correlated with poor outcome and predicted risk of relapse in pediatric B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to investigate the molecular mechanism by which CASP8AP2 regulates LEF1 expression by interacting with CtBP2 and ZEB2 in Acute lymphoblastic lymphoma (ALL). There was an interaction between CASP8AP2, ZEB2, and CtBP2, and then the interaction between CtBP2 and ZEB2 was observed after downregulating the expression of CASP8AP2. The wild type (containing the ZEB2 binding site) or mutant (containing a mutant binding site) LEF1 gene promoter sequence was inserted into the pGL3-basic plasmid, and a dual-luciferase reporter gene detection system was used to observe how CASP8AP2, ZEB2, and CtBP2 regulate the transcription of the LEF1 gene. We conclude that CASP8AP2, CtBP2, and ZEB2 can all bind to the LEF1 gene promoter region and reduce the luciferase activity of the LEF1 promoter. Meanwhile, the interaction of ZEB2 and the LEF1 promoter was significantly weakened after downregulation of CASP8AP2. Knockdown of CASP8AP2 in the 697 cell lines resulted in the significant upregulation of the mRNA expression levels of the stemness-related genes CD44, JAG1, and SALL4. In conclusion, CASP8AP2 is vital for the interaction between CtBP2 and ZEB2, inhibiting LEF1 and stemness-related genes expression ALL.Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2022.2033369 .

Initial respiratory support modality and outcome in preterm infants with less than 32 weeks of gestation in China: A multicentre retrospective cohort study.

BACKGROUND: For initial respiratory management, continuous positive airway pressure (CPAP) is increasingly used for preterm infants, especially for gestational age less than 32 weeks. However, neonatologists are concerned about the potential risks of CPAP support failure. OBJECTIVES: To examine the association between different initial respiratory support modalities and the outcomes of preterm infants at <32 weeks of gestation across multiple neonatal intensive care units (NICU) in China. METHODS: This study was carried out over a period of 12 months in 2018. Unadjusted relative risks (RR) for demographic and clinical characteristics were calculated for CPAP failure and CPAP success in the total cohort using log-linear model based on generalised estimating equations for clustered observations. RESULTS: Among 1560 preterm infants delivered at <32 weeks, the incidence of CPAP failure was 10.3%. After adjustment for demographic and clinical factors, the relative risk of mortality (RR 7.54, 95% CI 5.56, 10.44), pneumothorax (RR 9.85, 95% CI 2.89, 61.53), pulmonary haemorrhage (RR 7.78, 95% CI 4.51, 14.64) and BPD (RR 3.65, 95% CI 3.65, 4.51) were considerably higher for infants in the CPAP failure group than those in the CPAP-S group. However, the risk of poor outcomes in CPAP failure infants was similar to that of those in the initial mechanical ventilation (MV) group. CONCLUSIONS: Continuous positive airway pressure failure was associated with an increased risk of mortality and major morbidities, including BPD, pulmonary haemorrhage and pneumothorax, and was comparable to the risk associated with initial MV.

Design and development of a new type of phimosis dilatation retractor for children.

BACKGROUND: Phimosis is one of the most common diseases in children. Early selection of appropriate treatment for phimosis in children is beneficial to the development of their reproductive organs and significantly improves the prognosis of phimosis in children. Although traditional circumcision is the most widely used, it has many disadvantages, including postoperative bleeding and incision infection, pain, obvious scars on the surgical incision, and unsatisfactory appearance. In addition, there is much controversy regarding treatment options and timing at home and abroad. Surgical procedures such as circumcision and cerclage for children with excessively long foreskin will greatly affect the normal life of children after the operation. Young children need general anesthesia, but this anesthesia carries a great risk. AIM: To design a new children phimosis dilatation retractor for children phimosis. METHODS: The children phimosis was dilated with an elastic dilation frame, in order to expand the foreskin mouth and expose the penis head, and after that, the phimosis was cured. RESULTS: A new type of phimosis dilatation retractor was designed, which can gently dilate the prepuce at multiple angles and in multiple directions at the same time. It has obtained the national patent for clinical application. CONCLUSION: The phimosis dilatation retractor based on the principle of elastically expanding the prepuce can achieve the purpose of expanding the phimosis. The clinical application shows that the effect of the children phimosis retractor is significant, which is worth promoting.

Estimation of stature from radiographically determined lower limb bone length in modern Chinese.

To develop population - specific stature prediction equations from measurements of the lower limb bone in a contemporary Chinese. 303 individuals of Han group in Western China, including 201 females and 102 males were collected. The study sample was randomly divided into two subgroups. A calibration sample, which consisted of 171 females and 87 males, was used to develop the regression formula. A validation sample comprising the remaining 30 female and 15 male individuals was then used to test the predictive accuracy of the established formula. The regression equations were developed from intact bones and fragments of the femur, tibia and fibula, the maximum lengths of femur, tibia, and fibula were highly correlated with the stature. The maximum length of femur provide the most accurate result with the prediction accuracy of 3.84 cm for unknown sex, 4.00 cm in the male group, 3.45 cm in the female group, 3.61 cm in the group with age no more than 45, 3.45 cm in the group with age above 45. Moreover, the multiple regression equations were developed, and they portray a more accurate stature in instances in which the femur, tibia and fibula are available. This paper provides indications that the femur, tibia and fibula are important bones for stature estimation and they could be effectively used in forensic cases.

Association between admission hypothermia and outcomes in very low birth weight infants in China: a multicentre prospective study.

BACKGROUND: The objective of this prospective, multicentre, observational cohort study was to evaluate the association between admission hypothermia and neonatal outcomes in very low-birth weight (VLBW) infants in multiple neonatal intensive care units (NICUs) in China. METHODS: Since January 1, 2018, a neonatal homogeneous cooperative research platform-Shandong Neonatal Network (SNN) has been established. The platform collects clinical data in a prospective manner on preterm infants with birth weights (BWs) < 1500 g and gestational ages (GAs) < 34 weeks born in 28 NICUs in Shandong Province. These infants were divided into normothermia, mild or moderate/severe hypothermia groups according to the World Health Organization (WHO) classifications of hypothermia. Associations between outcomes and hypothermia were tested in a bivariate analysis, followed by a logistic regression analysis. RESULTS: A total of 1247 VLBW infants were included in this analysis, of which 1100 infants (88.2%) were included in the hypothermia group, 554 infants (44.4%) in the mild hypothermia group and 546 infants (43.8%) in the moderate/severe hypothermia group. Small for gestational age (SGA), caesarean section, a low Apgar score at 5 min and intubation in the delivery room (DR) were related to admission hypothermia (AH). Mortality was the lowest when their admission temperature was 36.5 ~ 37.5 °C, and after adjustment for maternal and infant characteristics, mortality was significantly associated with AH. Compared with infants with normothermia (36.5 ~ 37.5 °C), the adjusted ORs of all deaths increased to 4.148 (95% CI 1.505-11.437) and 1.806 (95% CI 0.651-5.009) for infants with moderate/severe hypothermia and mild hypothermia, respectively. AH was also associated with a high likelihood of respiratory distress syndrome (RDS), intraventricular haemorrhage (IVH), and late-onset neonatal sepsis (LOS). CONCLUSIONS: AH is still very high in VLBW infants in NICUs in China. SGA, caesarean section, a low Apgar score at 5 min and intubation in the DR were associated with increased odds of hypothermia. Moderate/severe hypothermia was associated with mortality and poor outcomes, such as RDS, IVH, LOS.

Clinical characteristics of four cancer patients with SARS-CoV-2 infection in Wuhan, China.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) led to the outbreak of pneumonia in Wuhan. The virus is highly infectious. Patients with cancer might be susceptible to the viral infection because of the immunosuppressive state cause by therapies on tumors. CASE PRESENTATION: We present the clinical features of four cancer patients who were infected with SARS-CoV-2 in late January of 2020 in our hospital. Cases 1 and 3 were diagnosed as mild and common type of coronavirus disease 2019 (COVID-2019) and survived from the viral infection. They acquired SARS-CoV-2 infection during their staying in hospital under radiotherapy and surgery of the tumors. Cases 2 and 4 suffered from severe type of COVID-19, and Case 2 was dead owning to the advanced age, uncontrolled chronic B cell lymphocytic leukemia and many other underlying diseases. The immunosuppressive state induced by liver transplantation and anti-rejection therapy might contribute to the severity of COVID-19 in Case 4, who suffered from hepatitis B related hepatocellular carcinoma. However, Case 4 was recovered from COVID-19 after a combination therapy against virus, bacteria and fungi, and also respiratory support. Nearly all patients showed a decrease in lymphocytes including total CD3+ T cells, B cells, and natural killer cells after infection of the virus. CONCLUSIONS: The severity of COVID-19 might be influenced by immune system state and underlying diseases in cancer patients. And the treatment of SARS-CoV-2 infection in cancer patients is challenged by the immunosuppressive state of these patients under chemotherapy or surgery.

Magnetic chitosan/sodium alginate gel bead as a novel composite adsorbent for Cu(II) removal from aqueous solution.

Using sodium alginate hydrogel as skeleton, in combination with chitosan and magnetic Fe3O4, a new type of magnetic chitosan/sodium alginate gel bead (MCSB) was prepared. Adsorptive removal of Cu(II) from aqueous solutions was studied by using the MCSB as a promising candidate in environmental application. Different kinetics and isotherm models were employed to investigate the adsorption process. Based on Fourier transform infrared spectroscopy, field-emission scanning electron microscope, CHNS/O elements analysis, vibration magnetometer, and various means of characterization, a comprehensive analysis of the adsorption mechanism was conducted. The MCSB had a good magnetic performance with a saturation magnetization of 12.5 emu/g. Elemental analysis proved that the addition of chitosan introduced a considerable amount of nitrogen-rich groups, contributing significantly to copper adsorption onto gel beads. The contact time necessary for adsorption was optimized at 120 min to achieve equilibrium. Experimental data showed that the adsorption process agreed well with the Langmuir isotherm model and the pseudo-second-order kinetics model. The theoretical maximum adsorption capacity of MCSB for Cu(II) could reach as high as 124.53 mg/g. In conclusion, the MCSB in this study is a novel and promising composite adsorbent, which can be applied for practical applications in due course.

Transcription factor E2F3a regulates CASP8AP2 transcription and enhances sensitivity to chemotherapeutic drugs in acute lymphoblastic leukemia.

BACKGROUND: Low expression of E2F3a and caspase 8 associated protein 2 (CASP8AP2) are associated with poor prognosis of childhood acute lymphoblastic leukemia (ALL). METHODS: Dual-luciferase reporter assay and wild type as well as four mutated types of reporter plasmids were used to demonstrate the activation of E2F3a on CASP8AP2 transcription. The direct binding of E2F3a with the promoter of CASP8AP2 was shown by Chromatin Immunoprecipitation (ChIP). Cell proliferation activity and cell cycle were determined by MTS and flow cytometry in leukemic cells after treating with common chemotherapeutic drugs vincristine and daunorubicin. RESULTS: In this study, we found that up-regulation of E2F3a in leukemic cells led to increased fraction of cells in S and G2/M phase, accelerated proliferation, and enhanced sensitivity to vincristine and daunorubicin. ChIP and luciferase assay indicated that E2F3a could directly bind to two fragments in the wild type of CASP8AP2 promotor (- 206 to - 69 and - 677 to - 507), and activate its transcription activity which was reduced in mutated promotors. The effect of E2F3a on chemotherapeutic sensitivity of leukemic cells could be reversed by down-regulating CASP8AP2. CONCLUSIONS: E2F3a could promote transcription and expression of CASP8AP2. The effect of E2F3a on chemotherapeutic sensitivity of ALL cells was implemented by regulating CASP8AP2 expression to a great extent.

[Spatial distribution and scale effect of species diversity of secondary forests in montane region of eastern Liaoning Province, China.] / è¾½ä¸œå±±åŒºæ¬¡ç”Ÿæž—ç‰©ç§å¤šæ ·æ€§çš„ç©ºé—´åˆ†å¸ƒåŠå°ºåº¦æ•ˆåº”.

With secondary forest in the montane region of eastern Liaoning Province as research object, this paper analyzed the spatial distribution and scale effect of Gleason richness index, Simpson dominance index, Shannon diversity index and Pielou evenness index in a 4 hm2 plot. The results showed that spatial distributions of the four diversity indices showed higher spatial heterogeneity. Variance of the four diversity indices varied with increasing scale. Coefficients of variation of the four diversity indices decreased with increasing scale. The four diversity indices of the tree layer were higher than those of the shrub layer, and the variation tendency varied with increasing scale. The results indicated that sampling scale should be taken into account when studying species diversity in the montane region of eastern Liaoning Province.

[Image quality adapted thoracic diameters in CT coronary artery imaging].

OBJECTIVE: To evaluate the correlation between image quality and thoracic diameters, anteroposterior diameter (AP) and right-left diameter (RL) for the optimization of reducing radiation dose in coronary artery imaging with Dual-source CT. METHODS: 118 patients underwent CT coronary artery imaging (CTCA) were divided into two groups (A and B) according to body mass index (BMI). There were 58 patients in group A with BMI values > or = 25 kg/m2 and < 30 kg/m2; and 60 patients in group B with BMI values < 25 kg/m2. Scan parameters: collimation 64 X 0.6 mm, reconstruction slice thickness 0.75 mm, reconstructin interval 0.7 mm, FOV 150-180 mm, the pitch adjusted according to heart rate automatically. CT imagings were obtained with tube voltage 100 kV, tube current 330 mAs (group A) and 100 kV, tube current 220 mAs (group B). The contrast-noise ratio (CNR), signal to noise ratio (SNR), as well as blind correlation test score values were calculated to establish the relationship among BMI, AP, RL and CNR, SNR. RESULTS: RL of five levels in groups of A, B were correlated to CNRa (P < 0.05). In group A and B (except iii, iv level of Group A), AP were associated with CNRa (P < 0.05). In addition to ii, iv level of group A, v level of group B, BMI were associated with CNRa (P < 0.05). The correlation coefficient of CNRa and RL of group A except ii level was greater than that of CNRa and AP. The correlation coefficient of CNRa, SNRa and RL of group B was greater than that of CNRa, SNRa and AP. Except iii level, the correlation coefficient of CNRa, SNRa and AP of group A was greater than that of CNRa, SNRa and BMI. Except ii level, the correlation coefficient of CNRa and AP of group B was greater than that of CNRa and BMI. CONCLUSION: Thoracic diameter of RL can be used as a guider to select the appropriate scan protocol in the coronary imaging acqusition with dual-source CT.

[Low-dose chest pain protocol for cardiac and chest imaging using dual-source computed tomography].

OBJECTIVE: To evaluate the clinical value of low-dose chest pain protocol for cardiac and chest vascular imaging using dual-source computed tomography. METHODS: 102 patients with requests for examinations of cardiac and thoracic blood vessels, were scanned in chest pain protocol for angiography. With heart electrical impulses dose control techniques, maximum tube current within the R-R interval was set up by different heart rate. Patients with a heart rate less than or equal to 75 beats/min were divided into two groups: regular-dose group (A) 28 patients; low-dose group (B) 25 patients. Patient with a heart rate of 76-120 beats/min were also divided into two groups: regular-dose group (C) 24 patients; low-dose group (D) 25 patients. The image quality of pulmonary artery, coronary artery and aortic were blind evaluated. The effective dose for each patient was calculated and group comparisons were made. RESULTS: Every radiation dose gained satisfactory images. No differences in image quality were found between Group A and Group B, and between Group C and Group D (P > 0.05). The effective doses of Group A (7.09 +/- 0.95) mSv were significantly higher than those of Group B (5.01 +/- 0.34) mSv. The effective doses of Group C (4.79 +/- 0.91) mSv were significantly higher than those of Group D (2.48 +/- 0.43) mSv. CONCLUSION; For patients with acute chest pain and relatively stable heart rate, their cardiac and thoracic vessels can be shown clearly in images of low-dose chest pain protocol, which provides a rapid and clear diagnostic instrument.

[The value of split-bolus 2-phase with virtual non-enhanced scan in CT urography].

OBJECTIVE: To investigate the value of split-bolus 2-phase with virtual non-enhanced scan in CT urography. METHODS: Eighty (80) patients with urinary obstruction were divided into two groups, group A was traditional CT urography scan, group B was split-bolus 2-phase with virtual non-enhanced scan. The scan sequence of group A included conventional scan first, then enhanced scan in arterial phase, parenchyma phase and excretion delayed phase after the injection of 100 mL contrast agent. The scan sequence of group B included conventional scan and enhanced scan following two bolus injection of contrast; the first injection of contrast was 40 mL, the second injection was 60 mL with 15-30 minutes delay, then enhanced scan was conducted in arterial and parenchymal phase, the parenchymal phase scan was performed with dual energy scanning sequence. The image quality of urinary collecting system, the detection of urinary obstructive lesion, and radiation dose were compared between the two groups. RESULTS: Between the two imaging methods, the imaging quality of urinary system did not show significant difference, but radiation dose was statistically significant difference. The radiation dose of split-bolus 2-phase with virtual non-enhanced scan was only 55% of traditional CTU scan. CONCLUSION: Split-bolus2 phase with virtual non-enhanced scan could obtain the same image quality as tranditional CTU, while reducing the approximately half the radiation dose.

[The value of dual-source dual-energy CT with iodine overlay in the diagnosis of acute necrotizing pancreatitis].

OBJECTIVE: To investigate the clinical value of dual-source computed tomography dual-energy Iodine overlay technique in the imaging diagnosis of acute necrotizing pancreatitis. METHODS: The imaging data were retrospectively analyzed in 67 cases of acute necrotizing pancreatitis underwent contrast-enhanced dual-source dual-energy CT in portal venous phase. The CT imaging parameters, including the difference of CT value between pancreatic parenchyma and necrotic lesion, contrast-to-noise ratio of pancreatic parenchyma-to-necrosis, area of pancreatic necrosis and score of subjective diagnosis, were measured and assessed on CT images of 80 kV, 140 kV, weighted-average 120 kV as well as Iodine overlay. RESULTS: The differences of CT value between pancreatic parenchyma and necrosis in the images of 80 kV, 140 kV, weighted-average 120 kV and Iodine overlay were (67.40 +/- 20.82) HU, (42.87 +/- 14.99) HU, (48.69 +/- 15.82) HU, (33.01 +/- 10.26) HU, respectively; contrast-to-noise ratios of pancreatic parenchyma-to-necrosis of each group were 8.36 +/- 3.58, 5.85 +/- 2.65, 7.68 +/- 3.51, 10.60 4.34; area of pancreatic necrosis of each group was (3.78 +/- 2.68) cm2, (3.28 +/- 2.59) cm2, (3.37 +/- 2.46) cm2, (2.42 +/- 1.98) cm2; the score of subjective diagnosis of each group was 3.88 +/- 0.33, 3.31 +/- 0.80, 3.58 +/- 0.66, 2.81 +/- 0.76, respectively. The four indexes in the images of Iodine overlay were significantly different from those of another three groups (P < 0.05). Contrast-to-noise ratio of pancreatic parenchyma-to-necrosis in the images of Iodine overlay was significantly higher than that of another three groups, while the difference of CT value, area of pancreatic necrosis and score of subjective diagnosis were lower. CONCLUSION; Dual-source CT dual-energy Iodine overlay is not helpful to improve subjective judgment in the diagnosis of pancreatic necrosis, but contributes to the display of hypoperfusion area around the necrosis.

[Dual-source dual-energy computed tomography imaging of acute necrotizing pancreatitis--Preliminary study].

OBJECTIVE: To investigate the clinical value of dual-source computed tomography dual-energy technology in the imaging diagnosis of acute necrotizing pancreatitis. METHODS: Thirty-two cases with diagnosed acute necrotizing pancreatitis and underwent contrast-enhanced dual-source dual-energy CT in portal venous phase were retrospectively analyzed. Difference of CT value between pancreatic parenchyma and necrosis, contrast to noise ratio of pancreatic parenchyma-to-necrosis and score of subjective diagnosis were measured, calculated and assessed on CT images of 80 kV, 140 kV and weighted-average 120 kV. RESULTS: The difference of CT value between pancreatic parenchyma and necrosis in the images of 80 kV, 140 kV and weighted-average 120 kV was (67.22 +/- 21.11) HU, (42.91 +/- 15.12) HU, (48.78 +/- 16.13) HU; contrast to noise ratio of pancreatic parenchyma-to-necrosis in the images of each group was 8.35 +/- 3.63, 5.89 +/- 2.67, 7.72 +/- 3.58; the score of subjective diagnosis in the images of each group was 3.87 +/- 0.34, 3.28 +/- 0.81, 3.56 +/- 0.67 respectively. Difference of CT value between pancreatic parenchyma and necrosis, contrast to noise ratio of pancreatic parenchyma-to-necrosis and score of subjective diagnosis were significantly different in three groups of images (P < 0.05). The three indexes at 80 kV were significantly higher than those of 140 kV and weighted-average 120 kV. CONCLUSION: At portal venous phase dual-sourcedual-energy enhancement CT, the demonstration of pancreas necrosis is better than those at 80 kV, 140 kV and weighted-average 120 kV in the diagnosis of acute necrotizing pancreatitis.

Fabrication of (Nd(0.01)La(x)Y(0.99-x))2O3 nanoparticles and transparent ceramics by combustion synthesis.

Y2O3 acts as the matrix material when doped with different content of La2O3 for reducing sintering temperature and refining grains. The (Nd(0.01)La(x)Y(0.99-x))2O3 nanoparticles and transparent ceramics are fabricated by a combustion synthesis. The powder feature is characterized by TEM. The microstructure, mechanical properties and transmittance of the samples are examined by SEM, HV-1000 hardness tester and fluorescence analyzer respectively. The results show that the (Nd(0.01)La(x)Y(0.99-x))2O3 nanoparticles are homogeneous in size and nearly spherical with average diameter in the range of 40-60 nm. There are no other phases except the Y2O3 cubic phase in the (Nd(0.01)La(x)Y(0.99-x))2O3 nanoparticles. The grains of the samples significantly reduce with increasing La2O3 content. The hardness and fracture toughness increase rapidly first and then gradually tend to plateau with increasing La2O3 content. The transmittance of sample also increases gradually with increasing La2O3, the largest transmittance exceeds 77% when the La2O3 content is x = 0.12.