Abnormalspontaneousbrainactivityintype2diabeticsretinopathyrevealedby amplitudeoflow-frequencyfluctuations:Aresting-statefMRIstudy / 实用放射学杂志

Objective Toinvestigatethealteredspontaneouscerebralactivitypatternsinpatientswithtype2diabeticretinopathy (DR).Methods 21patientswithDRand17healthycontrolsubjectswereprospectivelystudied.Allindividualsunderwentlaboratoryand neuropsychologicaltests.Thedifferencesintheamplitudeoflow-frequencyfluctuation (ALFF)valuesbetweentwogroupswere comparedandanalyzedstatisticallyusingDPRASFV2.3andREST1.6software.TherelationshipsamongALFFvaluesofbrainregionswith statisticalsignificance,HbA1c,durationofdiseaseandneuropsychologicalscoreswereanalyzedusinga multiple-factoranalysis.Results Comparedtothecontrols,theDRgroupshowedsignificantlyincreasedALFFvaluesinthebilateraloccipitalgyrus,rightlingualgyrus,and precuneus(P<0.01),anddecreasedvaluesintherightposterior/anteriorcerebellarlobe,fusiform,superiortemporal,inferiorparietal,and angulargyrus(P<0.05).Furthermore,theMoCAscoreswerenegativelycorrelatedwithdecreasedALFFvaluesintherightoccipitallobe oftheDRgroup,whileincreasedALFFvaluesintherightprecuneusandlingualgyruswerefoundtobepositivelycorrelatedwithglycosylated hemoglobin(HbA1c)levels.Conclusion PatientswithDRshowspontaneouscerebralabnormalactivityin manycerebralregions.ALFF valuechangesinthevisualcortexareassociatedwithcognitiveimpairments.Itisofimportantvaluetoevaluatebraindysfunctionin patientswithDRusingALFF method.

Resting-state functional magnetic resonance imaging study in type 2 diabetic retinopathy using regional homogeneity analysis / 实用放射学杂志

Objective To investigate the altered spontaneous cerebral activity in patients with type 2 diabetic retinopathy (T2DR). Methods Twenty-one patients with T2DR and sixteen healthy control subject underwent rs-fMRI scans,and the data were analyzed statistically using regional homogeneity(ReHo)method to observe the change of ReHo value.Results Compared to the control group,the T2DR group showed significantly increased ReHo value in the right occipital gyrus,occipital gyrus,inferior occipital gyrus and lingual gyrus regions (t=5.30,P＜0.05,voxel＞30,AlphaSim corrected),and significantly decreased ReHo value in the left posterior cingulate,margin lobe,right inferior parietal lobule,superior temporal gyrus and hippocampus (t=-4.01,-4.86,P＜0.05,voxel＞30, AlphaSim corrected).Conclusion The patients with T2DR showed significantly increased ReHo values in the brain visual cortex and visual pathway that were associated with the injury of brain function regions.It is of important value to evaluate brain dysfunction in patients with T2DR using ReHo method of rs-fMRI.

Preparation of anti-EGFR-PEG-SPIO molecular probe and its targeting MRI for lung adenocarcinoma cells / 中国医学影像技术

Objective To observe the targeting function of high affinity anti-EGFR monoclonal antibody (Cetuximab)conjugated superparamagnetic iron oxide-dopamine (anti-EGFR-PEG-SPIO) lung cancer cells via epidermal growth factor receptor (EGFR),as well as the feasibility for surveillance of tumor targeting with MRI.Methods Nanoparticles (NPs)of anti-EGFR-PEG-SPIO and PEG-SPIO were prepared,and the morphology of nanoparticles was observed with transmission electron microscope (TEM).The hydrodynamic diameter and R2 values of nanoparticles before and after conjugation with anti-EGFR were performed with dynamic light scattering (DLS) and MRI.MRI was performed in incubation with anti-EGFR-PEG-SPIO and PEG-SPIO after 2 h in vitro.The cellular uptake of anti-EGFR-PEG-SPIO and PEG-SPIO was further evaluated using Prussian blue staining and TEM.Results Anti-EGFR-PEG-SPIO and PEG-SPIO showed signal intensity of H460 cells on T2WI,decreased significantly compared with PEG-SPIO.The rate of signal intensity change was -58.2％,-82.7％,-94.4％ and-98.3％,respectively,at iron concentrations of (0,10,20,40,80 μg/ml) of antiEGFR-PEG-SPIO.Prussian blue staining and TEM showed that a lot of intracellular irons of anti-EGFR-PEG-SPIO were observed in H460 cells,but few of PEG-SPIO.Conclusion The effect of active targeting via anti-EGFR in EGFR overexpressed cells can be achieved with anti-EGFR-PEG-SPIO in H460 cells in vitro,and the targeting delivery process could be monitored with 3.0T MRI.