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Objective To investgate the application value of low-dose CT scanning in right adrenal vein imaging.Methods A total of 124 patients were enrolled in the study who were suspected as primary aldosteronism and requiring a contrast enhanced CT examination on adrenal glands.Four patients were excluded according to the exclusion criteria,so that the rest 120 patients were divided equally into three groups.Group A was a control group with conventional radiation dose using tube voltage of 120 kV and automatic mA.It was divided into A1,A2 and A3 groups according to arterial phase,portal venous phase and parenchymal phase.Group B was a experimental group with conventional tube voltage of 120 kV and automatic mA,which was divided into B1,B2 and n3 groups according to arterial phase,late arterial phase and portal venous phase.Group C was a low-dose experimental group with a tube voltage of 100 kV and a tube current of 150 mA only in the second phase,the remaining scanning parameters and method were the same as that of group B.The subjective scores of the images of groups A,B and C were statistically analyzed,and the CT values of the right adrenal vein(RAV),the right adrenal gland(RAG),and the fat of anterior abdominal wall at different scan phases were measured.The dose length products (DLP) were recorded and the signal-to-noise ratios (SNR),contrast-to-noise ratios (CNR),effective doses (E) of the three groups were calculated and compared.Results The subjective scores of the two observers were consistent (Kappa value =0.63);the subjective scores of the B2 images were statistically significant (H =7.18,P＜0.05).Difference of subjective scores between B2 and A2was statistically significant (t=-18.03,P＜0.05).The CT values of RAV,SNR,and CNR of the B2 group were higher than those of the A2 group (t=36.99,6.92,9.02,P＜0.05).The radiation dose comparison showed that the effective dose (E) was 45.52％ lower in the low-dose group than the conventional dose group with the statistically significant difference(t =12.19,P＜0.05).Conclusions Using MDCT scanning technique with lower tube voltage and lower tube current of 100 kV-150 mA,the detection rate of right adrenal vein can reach 95％ in the late arterial phase,and the effective dose can be reduced about 45.52％ on the basis of ensuring image quality.
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Objective To evaluate the clinical value of CT urography (CTU) in quantitative analysis of single?kidney renal glomerular filtration rate (GFR) in patients with renal tumor and hydronephrosis.Methods A total of 49 patients with renal tumor or hydronephrosis from January 2018 to September 2018 in the Second Hospital of Tianjin Medical University were prospectively collected. In all cases, the CT urography and 99mTc?DTPA renal dynamic imaging data and related clinical data were collected. All patients were divided into two groups: the experimental group (39 patients with a total of 78 kidneys) and the validation group (10 patients with a total of 20 kidneys). According to the presence or absence of renal diseases, the kidneys of the experimental group and the validation group were further divided into four groups, namely, the single kidney group, the tumor group, the stagnant water group and the healthy group. The CT urography protocol consisted of noncontrast, arterial phase, nephrographic, and excretory phase imaging. The total renal GFR was determined by CT measurement of renal clearance of contrast media (CM), and the total CT?GFR was then split into single?kidney CT?GFR by a left and right kidney proportionality factor. Differences between CT?GFR and SPECT?GFR measurements in each group of the experimental group was compared by paired?sample t test. Correlations between CT?GFR and SPECT?GFR in the experimental group and their correlations with RPV was analyzed by Pearson method. The Bland?Altman mapping method was used to evaluate the consistency between CT?GFR and SPECT?GFR in the experimental group. Results Paired difference between single?kidney CT?GFR (48.76 ± 18.50) ml·min-1·1.73 m-2 and single?kidney SPECT?GFR (45.68±17.95) ml·min-1·1.73 m-2 in the experimental group, P<0.05, demonstrating 6.8% systemic overestimation. A good correlation(r=0.80, P<0.01) and consistency (± 22.50 ml·min-1·1.73 m-2, ± 49.2% measurement deviations) was revealed between both measurements. There were positive correlations between CT?GFR and SPECT?GFR in the renal tumor group, hydronephrosis group, and healthy kidney group (r=0.67, 0.92, 0.80; P<0.01) respectively, and with good agreement (95% CI measurement deviation<30 ml·min-1·1.73 m-2). In all validation groups, there was no statistical difference between the estimated and true values of the Gates?GFR (all P>0.05). Pearson Correlation analysis showed that the correlations between CT?GFR and RPV in all experimental groups were better than the correlation between Gates?GFR and RPV (P<0.05). Conclusions This study demonstrated the feasibility of using CT urography to measure single?kidney GFR, verifying its application value in diseases such as kidney tumors and obstructive hydronephrosis, and proved that the proposed single?kidney CT?GFR correlates better than the SPECT?GFR with RPV.
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Objective To prepare pH-responsive osmotic nanocarriers (pMPPs),observe their distribution in the genital tract mucosa in mice,and evaluate their radiosensitizing effects in tumor cells.Methods Amphiphilic polymers containing pH-sensitive hydrazone bonds were synthesized and pMPPs were prepared by ultrasonic emulsification.At the same time,the hydrophobic polymer polylactic acid-glycolic acid copolymer (PLGA) and the amphiphilic polymer PLGA-polyethylene glycol without hydrazine bond were selected,and the mucoadhesive nanoparticles(MPs) and mucus-penetrating particles (MPPs) were prepared in the same way.Fluorescence microscopy was used to observe the distribution of three kinds of nanocarriers labeled with fluorescent dye Cy5.5 in the genital tract mucosa.The toxicity of nanocarriers to human cervical cancer cell line HeLa was tested by thiazolyl blue assay.The amphiphilic polymer containing pH-sensitive hydrazone bond was combined with oil-soluble gold nanoparticles to form a multi-encapsulated nanocarrier,and its radiotherapy sensitization effect in HeLa cells was evaluated by thiazole blue assay.Results The pMPPs were successfully prepared with relatively uniform particle size and good dispersion.Fluorescence microscopy showed that pMPPs not only had good mucus permeability,but also could improve the endocytosis efficiency of the nanocarriers in reproductive tract mucosa.The results of thiazolyl blue test showed that when the concentration of the carrier reached to 0.80 mg/ml,the survival rate of HeLa cells in the pMPPs group was higher than 90％ which was higher than that in the MPs and the MPPs groups,indicating that pMPPs had good biosafety.The HeLa cell survival rate of the CMNa group (0.80 mg/ml) was higher than that of the multi-package nanocarrier group under different doses of X-ray irradiation (4 Gy:82.90％ vs.61.79％;8 Gy:64.75 ％ vs.42.36％).This result indicated that compared with the CMNa,a commonly used clinical radiotherapy sensitizer,the multi-encapsulated nanocarriers can more effectively enhance the sensitivity of tumor cells to radiation therapy,thereby improving the lethality of radiation therapy on tumor cells.Conclusion This study solved the conflict between mucus permeation and endocytosis design of nanocarriers in mucosal tissue application,and provided new insight for the treatment of mucosal tissue diseases.
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Objective To prepare polyethylene glycol/cyclic asparagines-glycine-arginine functionalized gold nanoparticles (GNPs-PEG@cNGR) and evaluate their effectiveness in CT imaging of breast cancer angiogenesis.Methods The GNPs were synthesized by one-step reduction of chloroauric acid by sodium citrate.The thiolated PEG and cysteine-modified cNGR were coupled to the surface of GNPs through Au-S bonds,respectively.The GNPs-PEG@cNGR was characterized by transmission electron microscopy,Zeta potential/hydration particle size analyzer,and Fourier transform infrared spectrometer.The uptake and CT imaging effect of GNPs-PEG@cNGR were assessed by human umbilical vein endothelial cells (HUVEC) and human hepatoma cells (HepG2) positively expressed for aminopeptidase N (APN/CD 13).The in vivo CT imaging effects on tumor angiogenesis and biocompatibility in mice of GNPs-PEG@cNGR were studied by BALB/c mouse model of 4T1 breast cancer.Results A specific CT molecular probe,i.e.GNPs-PEG@cNGR,was successfully constructed,which can target angiogenesis.The probe was spherical,with a hydration particle size of (35.7± 1.0) nm and a Zeta potential of (-13.54± 1.12) mV,and had good stability and biocompatibility.The GNPs-PEG@cNGR has good CT imaging results and can specifically target CD13-positive HUVEC and HepG2 cells.The CT imaging results in 4T1 breast cancer mice indicated that GNPs-PEG@cNGR could be specifically enriched in the tumor tissue after injection.The CT value of tumors in GNPs-PEG@cNGRz group was higher than that of GNPs-PEG group,and the difference was statistically significant (P＜0.05).Conclusions GNPs-PEG@cNGR can specifically target CD13 positive cells and can be used as a CT contrast agent for imaging tumor angiogenesis.
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Objective To investigate the molecular mechanism of the effect of CYP2C19 polymorphism on the efficacy of clopidogrel in patients with stable coronary artery disease (SCAD).Methods A total of 208 patients with coronary artery disease undergoing percutaneous coronary intervention (PCI) were included.The CYP2C19 variant alleles were detected by gene sequencing.Platelet reactivity was assessed by thrombelastograph at 24 h after 300 mg clopidogrel loading.P2Y12-Gi signaling was measured by flow cytometric analysis of vasodilator-stimulated phosphorylation-platelet reactivity index (VASP-PRI) and Akt phosphorylation (P-Akt) index.Results Among 208 patients,40.9％ were classified as CYP2C19 * 1/* 1 (non-carriers) with no loss-of-function (LOF),44.7％ as CYP2C19 * 1/* 2 or CYP2C19 * 1/* 3 (one LOF carriers) and 14.4％ as CYP2C19 * 2/*2 or CYP2C19 * 2/* 3 (two LOF carriers).Both postclopidogrel platelet aggregation and VASP-PRI increased by the presence of one LOF allele,and were even more pronounced with the presence of two LOF alleles.In contrast,P-Akt index only increased in two LOF carriers.VASP-PRI was positively associated with postclopidogrel platelet aggregation (r =0.661,P＜0.001),but not with P-Akt index.Conclusions The two CYP2C19 LOF carriage was associated with more active state of P2Y12-Gi signaling in postclopidogrel platelet in Chinese patients with SCAD.
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The mechanisms leading to the occurrence of seizures in humans are still poorly understood. It is widely accepted, however, that the process of seizure generation is closely associated with an abnormal synchronization of neurons. In order to investigate this process, we have studied synchronization between different regions of the brain from intracranial EEG recordings of Pilocarpine-induced epileptic rat by Synchronization likelihood (SL). It was found that during the state of transition from non-epileptiform discharges to continuous-epileptiform discharges, synchronization between left-ECoG and left-EHG was significantly strengthened, and similar change had taken place between right-ECoG and right-EHGd; left-ECoG; and right-ECoG and left-EHG and right-EHG (P < 0.05). During the state of transition from continuous-epileptiform discharges to period-epileptiform discharges, the synchronization was significantly weakened between left-ECoG and left-EHG, and similar change was noted between left-EHG and right-EHG (P < 0.01). The results showed that SL might be used to assess the dynamics of synchronization and it might be helpful to understanding the mechanisms involving the origin of epileptiform discharge.