Objective To observe the value of MR mDixon-Quant sequence for differentiating chylous and non-chylous pleural effusions.Methods MR mDixon-Quant sequence data of 28 cases of chylous pleural effusion(chylous group)and 18 cases of non-chylous pleural effusion(non-chylous group)were retrospectively analyzed.The average fat fraction(FF)value of pleural effusion and the average FF value of lipid component aggregation area within pleural effusion were measured based on FF maps,respectively.Pearson correlation analysis was used to evaluate the relationships of laboratory indicators and FF values.Receiver operating characteristic curve was plotted,and the area under the curve(AUC)was calculated to evaluate the diagnostic efficacy of FF values measured using the above 2 methods for distinguishing chylous and non-chylous pleural effusions.Results The average FF value of pleural effusion showed moderate or weak positive correlations with triglyceride,total cholesterol and albumin(r=0.727,0.661,0.445,all P＜0.01).Taken 0.95％as the optimal cutoff value,the sensitivity,specificity and AUC of the average FF value of pleural effusion for distinguishing chylous from non-chylous pleural effusions was 85.71％,100％and 0.962,respectively.The average FF value of lipid component aggregation area in pleural effusion exhibited strong,moderate and weak positive correlations with triglyceride,total cholesterol and albumin,respectively(r=0.815,0.739,0.492,all P＜0.01).Taken 0.87％as the optimal cutoff value,the sensitivity,specificity and AUC of the average FF value of lipid component aggregation area in pleural effusion for distinguishing chylous from non-chylous pleural effusions was 92.86％,100％and 0.982,respectively.No significant difference of diagnostic performance was found between these 2 methods(P=0.203).Conclusion MR mDixon-Quant sequence enabled non-invasive discrimination of chylous and non-chylous pleural effusions.The average FF value of lipid component aggregation area could more accurately reflect the fat component of pleural effusion.

Objective To explore the CT and MR features of duodenal stromal tumors(DST).Methods The clinical,imaging and pathological data of patients with pancreaticoduodenal groove(PDG)mass detected by CT and/or MR,and pathologically diagnosed as DST were retrospectively analyzed.All imaging features were analyzed.Results Finally,all 11 patients were included,all of whom presented external mass in descending duodenum with clear boundary.There were 5 patients with irregular mass and 6 patients with circular mass.Two patients showed homogeneous mass on plain CT and MR imaging,while 9 patients presented heterogeneous mass(with varying degrees of calcification,hemorrhage,cystic degeneration,and necrosis),showed heterogeneous density on CT findings or high,low and iso signals on T1WI and T2WI without high signal on diffusion weighted imaging(DWI),and high enhancement on arterial phase,portal venous phase and delayed phase.There were no signs of air accumulation in all masses.Conclusion Stromal tumors commonly present external heterogeneous mass in descending duodenum with clear boundary.Familiarity with its predilection location and corresponding CT and MR findings are helpful for the qualitative diagnosis of DST.

Objective To observe the value of MR mDixon-Quant sequence for differentiating chylous and non-chylous pleural effusions.Methods MR mDixon-Quant sequence data of 28 cases of chylous pleural effusion(chylous group)and 18 cases of non-chylous pleural effusion(non-chylous group)were retrospectively analyzed.The average fat fraction(FF)value of pleural effusion and the average FF value of lipid component aggregation area within pleural effusion were measured based on FF maps,respectively.Pearson correlation analysis was used to evaluate the relationships of laboratory indicators and FF values.Receiver operating characteristic curve was plotted,and the area under the curve(AUC)was calculated to evaluate the diagnostic efficacy of FF values measured using the above 2 methods for distinguishing chylous and non-chylous pleural effusions.Results The average FF value of pleural effusion showed moderate or weak positive correlations with triglyceride,total cholesterol and albumin(r=0.727,0.661,0.445,all P＜0.01).Taken 0.95％as the optimal cutoff value,the sensitivity,specificity and AUC of the average FF value of pleural effusion for distinguishing chylous from non-chylous pleural effusions was 85.71％,100％and 0.962,respectively.The average FF value of lipid component aggregation area in pleural effusion exhibited strong,moderate and weak positive correlations with triglyceride,total cholesterol and albumin,respectively(r=0.815,0.739,0.492,all P＜0.01).Taken 0.87％as the optimal cutoff value,the sensitivity,specificity and AUC of the average FF value of lipid component aggregation area in pleural effusion for distinguishing chylous from non-chylous pleural effusions was 92.86％,100％and 0.982,respectively.No significant difference of diagnostic performance was found between these 2 methods(P=0.203).Conclusion MR mDixon-Quant sequence enabled non-invasive discrimination of chylous and non-chylous pleural effusions.The average FF value of lipid component aggregation area could more accurately reflect the fat component of pleural effusion.

Objective To explore the CT and MR features of duodenal stromal tumors(DST).Methods The clinical,imaging and pathological data of patients with pancreaticoduodenal groove(PDG)mass detected by CT and/or MR,and pathologically diagnosed as DST were retrospectively analyzed.All imaging features were analyzed.Results Finally,all 11 patients were included,all of whom presented external mass in descending duodenum with clear boundary.There were 5 patients with irregular mass and 6 patients with circular mass.Two patients showed homogeneous mass on plain CT and MR imaging,while 9 patients presented heterogeneous mass(with varying degrees of calcification,hemorrhage,cystic degeneration,and necrosis),showed heterogeneous density on CT findings or high,low and iso signals on T1WI and T2WI without high signal on diffusion weighted imaging(DWI),and high enhancement on arterial phase,portal venous phase and delayed phase.There were no signs of air accumulation in all masses.Conclusion Stromal tumors commonly present external heterogeneous mass in descending duodenum with clear boundary.Familiarity with its predilection location and corresponding CT and MR findings are helpful for the qualitative diagnosis of DST.

Objective:To evaluate the detective effect of double inversion recovery (DIR) sequence on cerebral white matter hyperintensities (WMH) in patients with acute ischemic stroke, and compare with those of T2WI and FLAIR sequences.Methods:Seventy-three acute ischemic stroke patients with WMH within 14 d of onset, admitted to Department of Neurology, Beijing Shijitan Hospital, Capital Medical University from November 2018 to March 2021, were chosen. MRI T2WI, FLAIR and DIR sequences were used to detect WMH. According to Fazekas scale, patients with periventricular white matter hyperintensities (PVWMH) or deep white matter hyperintensities (DWMH) were divided into mild group (score of 0-1) and moderate to severe group (scores≥2); the differences in WMH volume detected by T2WI, FLAIR and DIR sequences, and signal intensity, cross-sectional area and contrast of isolated lesions were compared.Results:(1) Seventy-three patients were with PVWMH (36 into the mild group and 37 into the moderate to severe group); in patients from the moderate to severe group, PVWMH volume detected by FLAIR sequence was statistically larger compared with that by DIR sequence, and PVWMH volume detected by T2WI sequence was significantly smaller compared with that by FLAIR sequence ( P<0.05). Fifty-seven patients were with DWMH (44 into the mild group and 13 into the moderate to severe group); the DWMH volume detected by FLAIR and T2WI sequences was significantly larger than that by DIR sequence ( P<0.05). (2) A total of 60 isolated lesions were detected, ranged 5.0-9.1 mm in length; isolated lesions enjoying significantly larger cross-sectional area, higher signal intensity, and lower contrast detected by FLAIR and T2WI sequences compared with those by DIR sequence ( P<0.05); isolated lesions enjoying significantly higher signal intensity and contrast detected by T2WI sequence compared with those by FLAIR sequence ( P<0.05). Conclusion:DIR sequence enjoys better effect in detecting WMH than FLAIR and T2WI sequences; the mismatch area of DIR sequence with FLAIR or T2WI sequences suggests WMH penumbra.

Abdomen/diagnostic imaging* ; Artificial Intelligence ; Body Composition ; Magnetic Resonance Imaging ; Practice Guidelines as Topic

Collectively migrating tumor cells have been recently implicated in enhanced metastasis of epithelial malignancies. In oral squamous cell carcinoma (OSCC), v integrin is a crucial mediator of multicellular clustering and collective movement ; however, its contribution to metastatic spread remains to be addressed. According to the emerging therapeutic concept, dissociation of tumor clusters into single cells could significantly suppress metastasis-seeding ability of carcinomas. This study aimed to investigate the anti-OSCC potential of novel endostatin-derived polypeptide PEP06 as a cluster-dissociating therapeutic agent . Firstly, we found marked enrichment of v integrin in collectively invading multicellular clusters in human OSCCs. Our study revealed that metastatic progression of OSCC was associated with augmented immunostaining of v integrin in cancerous lesions. Following PEP06 treatment, cell clustering on fibronectin, migration, multicellular aggregation, anchorage-independent survival and colony formation of OSCC were significantly inhibited. Moreover, PEP06 suppressed v integrin/FAK/Src signaling in OSCC cells. PEP06-induced loss of active Src and E-cadherin from cell-cell contacts contributed to diminished collective migration of OSCC . Overall, these results suggest that PEP06 polypeptide 30 inhibiting v integrin/FAK/Src signaling and disrupting E-cadherin-based intercellular junctions possesses anti-metastatic potential in OSCC by acting as a cluster-dissociating therapeutic agent.

Objective To study the feasibility of non-invasive spatially-resolved near-infrared spectroscopy (SR-NIRS) in clinical bedside monitoring of shock.Methods The central venous blood samples of 25 patients with shock were collected and the central internal jugular central vein oxygenation (ScvO2) level was measured.The self-developed non-invasive SR-NIRS device was used to measure tissue blood oxygen saturation (StO2) surrounding the region of jugular central vein.In addition,the artery oxygen saturation (SaO2) and partial pressure of oxygen (PO2) were also measured using conventional methods.The correlation between StO2 between ScvO2,SaO2 and PO2 was analyzed.Results StO2 levels in shock patients were highly correlated with ScvO2 levels (r=0.84,P＜0.001) and the concordance coefficient of 0.80 was high.Conclusion StO2 value collected from the surrounding region of jugular central vein by SR-NIRS device can be used as an indicator of shock suggesting the potential of noninvasive SR-NIRS for bedside shock monitoring.

Objective To explore the association of methylenetetrahydrofolate reductase (MTHFR)gene C677T polymorphism with weight gain induced by risperidone.Methods 356 patients with schizophrenia according to the DSM-IV criteria in this study.The height and body weight of the patients were measured before starting risperidone treatment and 8-week later.The MTHFRC677T polymorphism was genotyped using direct DNA sequencing method.Results A significant association was found between MTHFR gene C677T and body weight mass index (BMI) change after 8-week risperidone treatment.CC-carriers experienced higher BMI gain than CT/TT-carriers (CC (4.47 ± 1.09),CT (4.54 ± 1.27),TT (2.31 ± 0.75),F =5.634,P＜0.01).The frequency of allele C in bodyweight gain (＞7％) was higher than that in non-bodyweight gain groups (48.4％ vs 32.4％,x2=11.342,P＜0.01).Conclusion MTHFRC677T polymorphism is associated with risperidone induced weight gain in Chinese Han population.

Objective To evaluate the effect of magnetic resonance thoracic ductography (MRTD)in the diagnosis of right thoracic duct.Methods MRTD data were analyzed retrospective,and the detection rate of right thoracic duct was summarized and compared with that of lymphoscintigraphy,direct lymphangiography and operation.Results 12 cases of right thoracic duct were detected in 1547 cases of MRTD.The detection rate was 0.78%,in which 1 case was complied with total internal organs inversion,and 1 case with right aortic arch.Lymphoscintigraphy were performed in all 12 cases and right thoracic duct were detected in 4 cases.Direct lymphangiography were performed in 4 cases and right thoracic duct were observed in all of them.7 cases of them received right lum-bar duct adhesiolysis.Conclusion MRTD is a noninvasive method for diagnosis of right thoracic duct,which providing useful guid-ance for surgical operation.Its detection rate and diagnostic accuracy are higher than those of lymphoscintigraphy.