Objective To investigate correlations of the ratio of specific brain region volume to total brain volume(ratio％),standard uptake value(SUV)of specific brain region based on 18F-FDG PET/MR examination in Alzheimer disease(AD)patients,as well as the relationship between changes of these two.Methods Fifty AD patients were retrospectively collected.Based on FDG PET/MR,the ratio％and the mean SUV(SUVmean)of 40 specific brain regions were obtained,and the correlation between ratio％and SUVmean for each region were evaluated.According to a database of normal brains,Z-scores for ratio％and SUVmean were calculated to represent structural and functional changes in AD patients,and the correlation between these 2 Z-scores was assessed.Results Correlations were found between ratio％and SUVmean,also between Z-scores of these two parameters in 29 brain regions(r=0.288 to 0.778,all P＜0.05).Among them 7 brain regions,i.e.bilateral middle temporal gyrus,right fusiform gyrus,right hippocampus,right precuneus,left lingual gyrus and right parahippocampal gyrus exhibited correlation coefficients greater than 0.6.Conclusion There were some relationships between brain structural and metabolic functions and their changes in AD patients showed on FDG PET/MR.

A new X-ray phase contrast imaging method utilizing scanning absorption grid technology is proposed based on the study of X-ray phase contrast imaging with pinhole imaging principle.The method can effectively capture absorption,refraction,and scattering information of weakly absorbing biological samples.Experimental results show that the proposed method offers several advantages over traditional X-ray grating phase contrast imaging,including a simple imaging device,minimal X-ray source requirements,and enhanced compatibility with laboratory X-ray source or synchrotron radiation white beam.Consequently,it provides a new research mean for advancing current X-ray phase contrast imaging technology in clinical imaging research of large human organs.

Objective To investigate correlations of the ratio of specific brain region volume to total brain volume(ratio％),standard uptake value(SUV)of specific brain region based on 18F-FDG PET/MR examination in Alzheimer disease(AD)patients,as well as the relationship between changes of these two.Methods Fifty AD patients were retrospectively collected.Based on FDG PET/MR,the ratio％and the mean SUV(SUVmean)of 40 specific brain regions were obtained,and the correlation between ratio％and SUVmean for each region were evaluated.According to a database of normal brains,Z-scores for ratio％and SUVmean were calculated to represent structural and functional changes in AD patients,and the correlation between these 2 Z-scores was assessed.Results Correlations were found between ratio％and SUVmean,also between Z-scores of these two parameters in 29 brain regions(r=0.288 to 0.778,all P＜0.05).Among them 7 brain regions,i.e.bilateral middle temporal gyrus,right fusiform gyrus,right hippocampus,right precuneus,left lingual gyrus and right parahippocampal gyrus exhibited correlation coefficients greater than 0.6.Conclusion There were some relationships between brain structural and metabolic functions and their changes in AD patients showed on FDG PET/MR.

BACKGROUND: Double-stranded RNA-specific adenosine deaminase 1 (ADAR1) binds to double-stranded RNA and catalyzes the deamination of adenosine (A) to inosine (I). The functional mechanism of ADAR1 in non-small cell lung cancer (NSCLC) remains incompletely understood. This study aimed to investigate the prognostic significance of ADAR1 in NSCLC and to elucidate its potential role in regulating tumor cell proliferation and migration. METHODS: Data from The Cancer Genome Atlas (TCGA) and cBioPortal were analyzed to assess the correlation between high ADAR1 expression and clinicopathological features as well as prognosis in lung cancer. We performed Western blot (WB), cell proliferation assays, Transwell invasion/migration assays, and nude mouse xenograft modeling to examine the phenotypic changes and molecular mechanisms induced by ADAR1 knockdown. Furthermore, the ADAR1 p150 overexpression model was utilized to validate the proposed mechanism. RESULTS: ADAR1 expression was significantly elevated in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) tissues compared with adjacent non-tumor tissues (LUAD: P=3.70×10-15, LUSC: P=0.016). High ADAR1 expression was associated with poor prognosis (LUAD: P=2.03×10-2, LUSC: P=2.81×10-2) and distant metastasis (P=0.003). Gene Set Enrichment Analysis (GSEA) indicated that elevated ADAR1 was associated with mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway activation, matrix metalloproteinase-9 (MMP-9) expression, and cell adhesion. ADAR1 and MMP-9 levels showed a strongly positive correlation (P=6.45×10-34) in 10 lung cancer cell lines, highest in H1581. Knockdown of ADAR1 in H1581 cells induced a rounded cellular morphology with reduced pseudopodia. Concomitantly, it suppressed cell proliferation, invasion, migration, and in vivo tumorigenesis. It also suppressed ERK phosphorylation and downregulated cellular Finkel-Biskis-Jinkins murine osteosarcoma viral oncogene homolog (c-FOS), MMP-9, N-cadherin, and Vimentin. Conversely, ADAR1 p150 overexpression in PC9 cells enhanced ERK phosphorylation and increased c-FOS and MMP-9 expression. CONCLUSIONS High ADAR1 expression is closely associated with poor prognosis and distant metastasis in NSCLC patients. Mechanistically, ADAR1 may promote proliferation, invasion, migration, and tumorigenesis in lung cancer cells via the ERK/c-FOS/MMP-9 axis.
Humans ; Lung Neoplasms/physiopathology* ; Adenosine Deaminase/genetics* ; Matrix Metalloproteinase 9/genetics* ; Cell Proliferation ; Carcinoma, Non-Small-Cell Lung/physiopathology* ; Cell Movement ; Animals ; Mice ; RNA-Binding Proteins/genetics* ; Female ; Male ; Cell Line, Tumor ; Proto-Oncogene Proteins c-fos/genetics* ; Middle Aged ; MAP Kinase Signaling System ; Gene Expression Regulation, Neoplastic ; Mice, Nude ; Extracellular Signal-Regulated MAP Kinases/genetics*

A new X-ray phase contrast imaging method utilizing scanning absorption grid technology is proposed based on the study of X-ray phase contrast imaging with pinhole imaging principle.The method can effectively capture absorption,refraction,and scattering information of weakly absorbing biological samples.Experimental results show that the proposed method offers several advantages over traditional X-ray grating phase contrast imaging,including a simple imaging device,minimal X-ray source requirements,and enhanced compatibility with laboratory X-ray source or synchrotron radiation white beam.Consequently,it provides a new research mean for advancing current X-ray phase contrast imaging technology in clinical imaging research of large human organs.

Objective:To explore the value of 18F-FDG PET brain imaging in the auxiliary diagnosis of autoimmune encephalitis (AE) before treatment, and to analyze the regional and course-related characteristics of brain metabolic changes. Methods:The 18F-FDG PET brain imaging data of 49 AE patients (26 males, 23 females, age 48.0(29.0, 61.0) years) who did not receive first-line immunotherapy were retrospectively analyzed. Patients were collected from Renji Hospital, Shanghai Jiao Tong University School of Medicine, between July 2015 and December 2023. Forty-nine age- and gender-matched healthy subjects who underwent routine physical examination at the same time period were selected as the healthy controls (HC). The statistical parametric mapping (SPM) 8 two-sample t test ( P<0.001, k=50) was used to compare the imaging results of AE patients with those of HC. The screening results were adjusted by the cluster-level family-wise error rate (FWER) for P<0.05. Metabolic abnormalities associated with AE were identified, and differences in metabolic patterns at different stages of the disease course (short: ≤1 month; medium: >1 month and ≤3 month; long: >3 month) were compared by subgroup analysis. Mann-Whitney U test was used to analyze the data. Results:In the included AE patients, regions with elevated metabolism were mainly located in the limbic lobe, insula, putamen, and amygdala ( t values: 3.18-5.07, Z values: 3.17-4.76), while local metabolic reduction was observed in the frontal, parietal, and occipital lobes ( t values: 3.18-5.43, Z values: 3.23-5.06), with most of these regions passing FWER correction. In patients with anti- N-methyl- D-aspartate receptor (NMDAR) encephalitis, local metabolism increased in the right superior temporal gyrus ( t values: 3.55-4.79, Z values: 3.67-3.86) and decreased in the left middle temporal gyrus and inferior frontal gyrus ( t values: 3.55-5.43, Z values: 3.45-4.21), but the results did not pass the FWER correction. Subgroup analysis showed that in patients with short disease course ( n=17), regions with locally elevated metabolism included the brainstem, limbic lobe, and cerebellum ( t values: 3.37-5.27, Z values: 3.52-4.44), while regions with reduced metabolism were mainly located in the frontal, parietal, and occipital lobes ( t values: 3.37-6.77, Z values: 3.34-5.30), and these abnormal results all passed FWER correction. In patients with medium ( n=7) to long ( n=25) disease course, the regions with metabolic abnormalities were significantly reduced and did not pass FWER correction. Conclusions:18F-FDG PET can accurately identify brain metabolic abnormalities in AE patients, demonstrating significant regional and course-related characteristics. Metabolic abnormalities are more pronounced in patients with short disease course, while they are relatively less obvious in patients with medium to long disease course.

Objective:To explore the value of 18F-FDG PET brain imaging in the auxiliary diagnosis of autoimmune encephalitis (AE) before treatment, and to analyze the regional and course-related characteristics of brain metabolic changes. Methods:The 18F-FDG PET brain imaging data of 49 AE patients (26 males, 23 females, age 48.0(29.0, 61.0) years) who did not receive first-line immunotherapy were retrospectively analyzed. Patients were collected from Renji Hospital, Shanghai Jiao Tong University School of Medicine, between July 2015 and December 2023. Forty-nine age- and gender-matched healthy subjects who underwent routine physical examination at the same time period were selected as the healthy controls (HC). The statistical parametric mapping (SPM) 8 two-sample t test ( P<0.001, k=50) was used to compare the imaging results of AE patients with those of HC. The screening results were adjusted by the cluster-level family-wise error rate (FWER) for P<0.05. Metabolic abnormalities associated with AE were identified, and differences in metabolic patterns at different stages of the disease course (short: ≤1 month; medium: >1 month and ≤3 month; long: >3 month) were compared by subgroup analysis. Mann-Whitney U test was used to analyze the data. Results:In the included AE patients, regions with elevated metabolism were mainly located in the limbic lobe, insula, putamen, and amygdala ( t values: 3.18-5.07, Z values: 3.17-4.76), while local metabolic reduction was observed in the frontal, parietal, and occipital lobes ( t values: 3.18-5.43, Z values: 3.23-5.06), with most of these regions passing FWER correction. In patients with anti- N-methyl- D-aspartate receptor (NMDAR) encephalitis, local metabolism increased in the right superior temporal gyrus ( t values: 3.55-4.79, Z values: 3.67-3.86) and decreased in the left middle temporal gyrus and inferior frontal gyrus ( t values: 3.55-5.43, Z values: 3.45-4.21), but the results did not pass the FWER correction. Subgroup analysis showed that in patients with short disease course ( n=17), regions with locally elevated metabolism included the brainstem, limbic lobe, and cerebellum ( t values: 3.37-5.27, Z values: 3.52-4.44), while regions with reduced metabolism were mainly located in the frontal, parietal, and occipital lobes ( t values: 3.37-6.77, Z values: 3.34-5.30), and these abnormal results all passed FWER correction. In patients with medium ( n=7) to long ( n=25) disease course, the regions with metabolic abnormalities were significantly reduced and did not pass FWER correction. Conclusions:18F-FDG PET can accurately identify brain metabolic abnormalities in AE patients, demonstrating significant regional and course-related characteristics. Metabolic abnormalities are more pronounced in patients with short disease course, while they are relatively less obvious in patients with medium to long disease course.

Purpose To investigate the clinicopathological and molecular features of colorectal micropapillary carcinoma(MPC),and to provide evidence for the diagnosis and individu-al treatment of colorectal MPC.Methods The clinicopathologi-cal and molecular data of 461 patients with colorectal cancer were collected retrospectively,including 56 cases of colorectal MPC and 405 cases of colorectal adenocarcinoma not otherwise specified(NOS).The expression of 4 mismatch repair proteins(MLH1,PMS2,MSH2,MSH6)and p53 protein was detected by immunohistochemistry.The hot spot mutations of KRAS,NRAS,PIK3CA and BRAF genes were detected by ARMS-PCR,to analyze the difference of clinicopathological and molec-ular features between colorectal MPC and adenocarcinoma NOS.Results The vessel invasion rate and lymph node metastasis rate of colorectal MPC were significantly higher than those of ad-enocarcinoma NOS(42.9％vs 23.0％,P=0.001;67.9％vs 46.2％,P=0.002).The incidence of mismatch repair defi-ciency in colorectal MPC was significantly lower than that in ade-nocarcinoma NOS(3.6％vs 13.8％,P=0.030).The hot spot mutation rate in exon 2,3 and 4 of KRAS gene in colorectal MPC was significantly higher than that in adenocarcinoma NOS(58.9％vs 42.2％,P=0.018),especially in KRAS G13D(17.9％vs 8.1％,P=0.019).The proportion of colorectal MPC components was not associated with clinicopathological and molecular features.There were no significant differences in clin-icopathological and molecular features between colorectal MPC and adenocarcinoma NOS with high-grade tumor budding.Con-clusion The clinicopathologic and molecular features of color-ectal MPC are different from those of adenocarcinoma NOS,and the diagnosis of this subtype may provide help for the formulation of treatment plan and the evaluation of prognosis.

Objective:To evaluate the values of 18F-PI-2620 PET/CT brain imaging with SUV ratio (SUVR) in the assessment of tau protein deposition in the brain of patients with different cognitive disorders and its correlation with cognition. Methods:This was a cross-sectional study. From December 2019 to November 2022, a total of 67 subjects including 54 patients with Alzheimer′s disease (AD; 21 males, 33 females, age (68.6±7.8) years), 7 patients with mild cognitive impairment (MCI; 1 male, 6 females, age (63.1±11.2) years) and 6 healthy controls (HC; 4 males, 2 females, age (69.0±5.8) years) were enrolled retrospectively in Renji Hospital. All participants were examined by 18F-PI-2620 PET/CT. SUVRs of brain regions were obtained, including frontal lobe, temporal lobe, occipital lobe, parietal lobe, insular lobe, whole brain, as well as 10 independent brain ROIs (amygdala, orbitofrontal cortex, cingulate gyrus, superior occipital gyrus, superior parietal gyrus, inferior angular gyrus, precuneus, inferior temporal gyrus, entorhinal cortex and parahippocampal gyrus), with inferior cerebellum cortex as the reference region. All participants were estimated by cognitive scales(mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA)). One-way analysis of variance and the least significant difference t test were used to compare the differences of SUVR in each brain region among HC, MCI and AD groups. ROC curve analysis was used to determine the optimal cut-off values of SUVR in each brain region for the differential diagnosis of AD-MCI and AD-HC. Pearson correlation analysis was employed to examine the correlations of SUVR with cognitive scale scores. Results:The SUVR of whole brain was 1.40±0.31 in AD group, 1.08±0.19 in MCI group, and 1.01±0.12 in HC group. SUVR analysis in the whole brain and each brain region could distinguish AD from HC, AD from MCI ( F values: 1.76-10.09, t values: 2.98-7.47, all P<0.05), but could not distinguish HC from MCI ( t values: 0.17-1.53, all P>0.05). ROC curve analysis showed that the best cut-off value of SUVR was 1.18 for whole brain (AUC=0.89), 1.13 for amygdala (AUC=0.94) and 1.26 for parahippocampal gyrus (AUC=0.94) for differential diagnosis of AD and HC, which was 1.06 for whole brain (AUC=0.82), 1.18 for amygdala (AUC=0.88) and 1.28 (AUC=0.88) for infratemporal gyrus to differential diagnosis of AD and MCI. SUVRs of the whole brain, frontal, occipital, parietal, temporal and insula were significantly negatively correlated with MMSE and MoCA cognitive scale scores ( r values: from -0.64 to -0.40, all P<0.05). Conclusions:SUVR quantitative analysis in 18F-PI-2620 PET imaging can assist the differential diagnosis of AD and HC, AD and MCI. The SUVRs of whole brain and five lobes show negative correlations with MMSE and MoCA scores.

Objective:To assess the diagnostic efficiency of 18F-FDG PET for Alzheimer′s disease (AD) in patients with memory impairment. Methods:A retrospective analysis was conducted on 96 patients (40 males, 56 females, age: 69.0(62.8, 74.0) years) initially diagnosed with memory impairment in Renji Hospital, School of Medicine, Shanghai Jiao Tong University between August 2019 and September 2023. The amyloid-tau-neurodegeneration (ATN) criteria, based on 18F-AV45+ 18F-PI-2620 PET/CT+ MRI imaging results, were used as the diagnostic standard for AD. Visual analysis (temporoparietal or posterior cingulate cortex (PCC) hypometabolism) and semi-quantitative analysis methods (PET-SCORE and NeuroQ software analysis (SUV ratio, SUVR)) were applied to evaluate the diagnostic efficiency of 18F-FDG PET imaging for AD. Diagnostic efficiencies of visual assessment and semi-quantitative parameters were compared by χ2 test. Additionally, Pearson correlation analysis was performed to examine the relationship between results of PET-SCORE and cognitive scales. Results:Of the 96 patients initially diagnosed with memory impairment, 61 were clinically diagnosed with AD, while 35 were non-AD patients. Visual assessment of temporoparietal hypometabolism showed the highest sensitivity (91.80%, 56/61), which was significantly different from the sensitivities of PET-SCORE (40.98%(25/61); χ2=29.03, P<0.001) and visual assessment of PCC hypometabolism (77.05%(47/61); χ2=5.82, P=0.016). While semi-quantitative assessment using PET-SCORE demonstrated the highest specificity (100%, 35/35), which was significantly different from the specificities of visual assessment methods (temporoparietal hypometabolism: 17.14%(6/35), χ2=27.03, P<0.001; PCC hypometabolism: 54.29%(19/35), χ2=14.06, P<0.001). PET-SCORE exhibited statistically significant correlations with Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Activities of Daily Living (ADL) scores ( r values: -0.38, -0.36, 0.31, all P<0.01). Conclusions:Among patients initially diagnosed with memory impairment, visual assessment in 18F-FDG PET imaging analysis demonstrates higher sensitivity, while semi-quantitative analysis using PET-SCORE exhibits higher specificity. PET-SCORE shows statistically significant correlation with the severity of cognitive decline.