Expression characteristics of peripheral lymphocyte programmed death 1 and FoxP3+ Tregs in gastric cancer during surgery and chemotherapy

BACKGROUND Programmed death 1(PD-1)and CD4^(+)CD25^(+)FoxP3^(+)expression in peripheral blood T-cells has been previously reported in various types of cancer.However,the specific variation tendency during surgery and chemotherapy,as well as their relationship in gastric cancer patients,still remain unclear.Understanding this aspect may provide some novel insights for future studies on tumor recurrence and tumor immune escape,and also serve as a reference for determining the optimal timing and dose of clinical anti-PD-1 antibodies.AIM To observe and analyze the expression characteristics of peripheral lymphocyte PD-1 and FoxP3^(+)regulatory T cells(FoxP3^(+)Tregs)before and after surgery or chemotherapy in gastric cancer patients.METHODS Twenty-nine stomach cancer patients undergoing chemotherapy after a D2 gastrectomy provided 10 mL peripheral blood samples at each phase of the perioperative period and during chemotherapy.This study also included 29 agematched healthy donors as a control group.PD-1 expression was detected on lymphocytes,including CD4^(+)CD8^(+)CD45RO^(+),CD4^(+)CD45RO^(+),and CD8^(+)CD45RO^(+)lymphocytes as well as regulatory T cells.RESULTS We observed a significant increase of PD-1 expression on immune subsets and a larger number of FoxP3^(+)Tregs in gastric cancer patients(P<0.05).Following D2 gastrectomy,peripheral lymphocytes PD-1 expression and the number of FoxP3^(+)Tregs notably decrease(P<0.05).However,during postoperative chemotherapy,we only observed a decrease in PD-1 expression on lymphocytes in the CD8^(+)CD45RO^(+)and CD8^(+)CD45RO^(+)populations.Additionally,linear correlation analysis indicated a positive correlation between PD-1 expression and the number of CD4^(+)CD45RO^(+)FoxP3high activated Tregs(aTregs)on the total peripheral lymphocytes(r=0.5622,P<0.0001).CONCLUSION The observed alterations in PD-1 expression and the activation of regulatory T cells during gastric cancer treatment may offer novel insights for future investigations into tumor immune evasion and the clinical application of anti-PD-1 antibodies in gastric cancer.

Prediction of radiosensitivity in primary central nervous system germ cell tumors using dynamic contrast-enhanced magnetic resonance imaging

Objective： To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging（DCEMRI） for predicting tumor response to radiotherapy in patients with suspected primary central nervous system（CNS） germ cell tumors（GCTs）.Methods： DCE-MRI parameters of 35 patients with suspected primary CNS GCTs were obtained prior to diagnostic radiation, using the Tofts and Kermode model. Radiosensitivity was determined in tumors diagnosed 2 weeks after radiation by observing changes in tumor size and markers as a response to MRI. Taking radiosensitivity as the gold standard, the cut-off value of DCE-MRI parameters was measured by receiver operating characteristic（ROC） curve. Diagnostic accuracy of DCE-MRI parameters for predicting radiosensitivity was evaluated by ROC curve.Results： A significant elevation in transfer constant（K^trans） and extravascular extracellular space（Ve）（P=0.000）, as well as a significant reduction in rate constant（Kep）（P=0.000） was observed in tumors. K^trans, relative K^trans, and relative Kep of the responsive group were significantly higher than non-responsive groups. No significant difference was found in Kep, Ve, and relative Ve between the two groups. Relative K^trans showed the best diagnostic value in predicting radiosensitivity with a sensitivity of 100%, specificity of 91.7%, positive predictive value（PPV） of 95.8%, and negative predictive value（NPV） of 100%.Conclusions： Relative K^trans appeared promising in predicting tumor response to radiation therapy（RT）. It is implied that DCE-MRI pre-treatment is a requisite step in diagnostic procedures and a novel and reliable approach to guide clinical choice of RT.

MRI Manif estions Correlate with Survival of Glioblastoma Multiforme Patients

Objective To identify the correlation between magnetic resonance manifestation and survival of patients with glioblastoma lnultiforme （GBM）, Methods The magnetic resonance imaging （MRI） images of 30 glioblastoma patients were collected. Imaging features including degrees of contrasted area, edema surrounding the tumor; and intensity in T2-weighted imaging were selected to determine their correlation with patient survival. The relationship between imaging and survival time was studied using SPSS 19.0 software. Kaplan- Meier survival analysis and log-rank test were used to compare the survival curves. Results Patients with 〈5% contrasted enhancement area of tumor had longer overall survival （OS） than those with 〉5% contrasted enhancement area of tumor. Patients without edema surrounding the tumor had longer OS than those with edema. Patients with tumor of hyperintensity and/or isointensity in T2-weighted imaging had longer OS than those with hyperintensity and/or isointensity and hypointensity. Conclusions Some MR imaging features including degrees of contrasted area, edema surrounding the tumor, and intensity in T2- weighted imaging are correlated with the survival of patients with GBM. These features can serve as prognostic indicators for GBM patients.

Development and validation of a nutrition-related genetic-clinical-radiological nomogram associated with behavioral and psychological symptoms in Alzheimer’s disease

Background:Few evidence is available in the early prediction models of behavioral and psychological symptoms of dementia(BPSD)in Alzheimer’s disease(AD).This study aimed to develop and validate a novel genetic-clinical-radiological nomogram for evaluating BPSD in patients with AD and explore its underlying nutritional mechanism.Methods:This retrospective study included 165 patients with AD from the Chinese Imaging,Biomarkers,and Lifestyle(CIBL)cohort between June 1,2021,and March 31,2022.Data on demographics,neuropsychological assessments,single-nucleotide polymorphisms of AD risk genes,and regional brain volumes were collected.A multivariate logistic regression model identified BPSD-associated factors,for subsequently constructing a diagnostic nomogram.This nomogram was internally validated through 1000-bootstrap resampling and externally validated using a time-series split based on the CIBL cohort data between June 1,2022,and February 1,2023.Area under receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA)were used to assess the discrimination,calibration,and clinical applicability of the nomogram.Results:Factors independently associated with BPSD were:CETP rs1800775(odds ratio[OR]=4.137,95%confidence interval[CI]:1.276-13.415,P=0.018),decreased Mini Nutritional Assessment score(OR=0.187,95%CI:0.086-0.405,P<0.001),increased caregiver burden inventory score(OR=8.993,95%CI:3.830-21.119,P<0.001),and decreased brain stem volume(OR=0.006,95%CI:0.001-0.191,P=0.004).These variables were incorporated into the nomogram.The area under the ROC curve was 0.925(95%CI:0.884-0.967,P<0.001)in the internal validation and 0.791(95%CI:0.686-0.895,P<0.001)in the external validation.The calibration plots showed favorable consistency between the prediction of nomogram and actual observations,and the DCA showed that the model was clinically useful in both validations.Conclusion:A novel nomogram was established and validated based on lipid metabolism-related genes,nutritional status,and brain stem volumes,which may allow patients with AD to benefit from early triage and more intensive monitoring of BPSD.Registration:Chictr.org.cn,ChiCTR2100049131.

The clinical,radiological,and surgical characteristics of anterior perforated substance glioma:a retrospective study

Background To explore the clinical,radiological,and surgical characteristics of anterior perforated substance(APS)gliomas.Methods Twenty patients with APS glioma who were treated with surgery between March 2019 and January 2022 from Tiantan hospital were retrospectively reviewed.The clinical,histological and radiological data were collected.Results Twenty patients,including 7 males(55%)and 13 females(45%),with a mean age at diagnosis of 37.9 years(range,28-53 years)underwent operative intervention for APS.Headaches and dizziness were the most common preoperative symptoms in the majority patients(14,70%).Based on radiological features of MRI,the APS was classified into two subtypes,type A and type B.Seven patients(40%)in type A indicated a clear tumor margin,while 13 patients(60%)in type B showed an ill-defined margin.The surgical approach including frontal,temporal,and coronal frontal incisions for type A and type B tumors,respectively.Three patients in type A received total resection,while one patient in type B were total resected.Pathologically,12 cases(60%,12/20)were diagnosed as astrocytoma and 8 cases(20%,8/20)were oligodendroglioma.Meanwhile,17 cases(85%,17/20)had MGMT promotor methylation.Conclusion In this study,we performed the first systematic research of patients with APS glioma.Most of patients with APS presented headaches and dizziness symptoms.The APS glioma was further divided into two major radiological subtypes with relevant different surgical approaches.The APS glioma in type A were more likely to receive total resection.

超高场MRI:脑部成像结果探讨(英文)

随着射频和线圈技术的提高,超高场磁共振近年来有了很大的发展。与常规的场强,超高场MR主要具有以下优势:(1)信噪比的显著增加保证了高分辨率和高质量的图像,从而大大提高了微小结构的检出;(2)由于磁敏感效应的增加,T2*或磁敏感技术有了更广泛的应用,尤其是对异常的铁沉积,微小出血点和小静脉血管的检测;(3)高场T1弛豫时间的增加可以提高ASL灌注成像技术的应用;(4)信号本身的增加也可提高fMRI和MRS的分辨率等。当然,目前超高场强磁共振技术也还有一些局限性:(1)SAR的明显增加限制了采集层数并影响采集时间;(2)高场下RF磁场(B1)的不均匀性造成图像信号的不均匀;(3)增加的磁敏感效应也在颅底增加了相应的伪影等。本文对高场7T在纽约大学医疗中心脑部MR的最初临床应用结果 进行了分析。

White Matter Changes in Alzheimer’s Disease Revealed by Diffusion Tensor Imaging with TBSS

Alzheimer’s disease (AD) is a progressive, neurodegenerative disorder characterized by impairments in multiple cognitive domains and it is hard to diagnose in early stage because it’s not easy to recognize and develop slowly. In this study, we try to evaluate the difference of white matter between AD and health volunteers using diffusion tensor imaging (DTI) and try to provide some evidence for diagnose AD in early stage. Twelve elderly Chinese patients with AD and twelve healthy volunteers were recruited and underwent DTI. The raw diffusion data were dealt with the toolkit of FSL image post-processing. Fractional anisotrogy (FA) data were then carried out by using tract-based spatial statistics (TBSS). The result showed that the FA of cingulum, hippocampus, corticospinal tract, and inferior fronto-occipital fasciculus significantly reduced in AD patients than that of volunteers. This indicated that the integrity of white matter tracts in these regions with AD was disturbed. On the other hand, the FA of other encephalic regions had no discrepancy compared with that of healthy volunteers. FA values were found reduced significantly in AD patients, especially in the posterior of the brain. These findings may provide image methods to diagnose patients with early stage of AD.

DeepWMH:无需人工标注训练的脑白质高信号病灶分割工具

White matter hyperintensities(WMHs)on fluid-attenuated inversion recovery(FLAIR)images are imaging features in various neurological diseases and essential markers for clinical impairment and disease progression.WMHs are associated with brain aging and pathological changes in the human brain,such as in Alzheimer’s disease(AD)[1],Parkinson’s disease(PD)[2],cerebral small vessel disease(SVD)[3],multiple sclerosis(MS)[4].

Haemodynamic analysis of adult patients with moyamoya disease: CT perfusion and DSA gradings

Object Moyamoya disease(MMD)is a common and chronic progressive stenotic-occlusive cerebrovascular disease in Eastern Asia.To evaluate the hemispheric haemodynamic status of adult patients with MMD,we explored the potential risk factors of hemispheric perfusion alterations with CT perfusion(CTP)and DSA.Methods We retrospectively reviewed 44 male and 44 female(176 hemispheres)adult patients with MMD who had both DSA and CTP.Data on cerebral blood perfusion(CBF),cerebral blood volume(CBV),mean transmit time(MTT),time to peak(TTP)of cerebral hemisphere and cerebellum were gathered and difference of relative haemodynamic parameters between different subgroups were assessed with independent sample t analysis,one-way analysis of variance and general linear regression analysis.Results Parameters in regional CBF(rCBF)of frontal,temporal lobe and basal ganglia in female was more superior than male.rCBF,regional MTT(rMTT)and regional TTP(rTTP)in adult MMD patients with haemorrhage were superior than the ischaemic.With the increase of age,significant difference could be seen in rCBF and rCBV of thalamus.However,with progress of arterial stenosis,significant difference could only be obsevrved in rCBV,rMTT and rTTP,whereas rCBF had no significant difference.For increase of moyamoya vessels,significant decrease of rCBF could be seen in temporal and parietal lobe.With the increase of compensatory artery numbers,no significant difference could be seen in rCBF parameters(p>0.05).Conclusions In adult MMD patients,age,gender and clinical type were potential risk factors for the change of cerebral perfusion.When arterial stenosis is worsened,moyamoya vessels could alter perfusion of temporal and parietal lobe,but not frontal lobe.Extracranial/intracranial compensatory arteries could maintain microcirculation stability in frontal lobe and basal ganglia,indicating that the protection from extracranial compensatory arteries,a theoretic base for surgery treatment if necessary.

Association of apolipoprotein E epsilon 4 and cognitive impairment in adults living with human immunodeficiency virus: a meta-analysis

Background: It is controversial whether the apolipoprotein E epsilon 4 allele (APOE ε4) is a risk gene for human immunodeficiency virus (HIV)-related neurocognitive impairment. This meta-analysis aimed to summarize evidence of the associations betweenAPOE ε4 and cognitive impairment in people living with HIV (PLWH).Methods: Our study conducted a systematic literature search of PubMed, Web of Science, Embase, Google Scholar, and ProQuest for studies published before April 11, 2022 that evaluated associations betweenAPOE ε4 and cognitive impairment in adult PLWH (aged ≥18 years). We calculated pooled odds ratios (ORs) of global cognitive impairment and 95% confidence intervals (CIs) and standardized mean differences (SMDs) for specific cognitive domains betweenAPOE ε4 carriers and non-carriers. Subgroup meta-analyses were used to evaluate the result profiles across different categorical variables.Results: Twenty studies met the inclusion criteria, including 19 that evaluated global cognitive impairment.APOE ε4 was significantly associated with global cognitive impairment in PLWH (OR = 1.36, 95% CI = [1.05, 1.78], number of estimates [k] = 19,P = 0.02, random effects). Subgroup meta-analysis based percentage of females showed evident intergroup differences in global cognitive performance between ε4 carriers and non-carriers (P = 0.015).APOE ε4 carriers had lower cognitive test scores than non-carriers in all seven cognitive domains, including fluency (SMD = -0.51, 95% CI = [-0.76, -0.25],P < 0.001,k = 4,I^(2)= 0%), learning (SMD = -0.52, 95% CI = [-0.75, -0.28],P < 0.001,k = 5,I^(2) = 0%), executive function (SMD = -0.41, 95% CI= [-0.59, -0.23],P < 0.001,k= 8,I^(2)= 0%), memory (SMD=-0.41, 95% CI= [-0.61, -0.20],P < 0.001,k= 10,I^(2)= 36%), attention/working memory (SMD=-0.34, 95% CI= [-0.54, -0.14],P= 0.001,k= 6,I^(2)= 0%), speed of information processing (SMD = -0.34, 95% CI = [-0.53, -0.16],P < 0.001,k = 8,I^(2) = 0%), and motor function (SMD = -0.19, 95% CI = [-0.38, -0.01],P = 0.04,k = 7,I^(2) = 0%).Conclusions: Our meta-analysis provides significant evidence thatAPOE ε4 is a risk genotype for HIV-associated cognitive impairment, especially in cognitive domains of fluency, learning, executive function, and memory. Moreover, the impairment is sex specific.Meta analysis registration: PROSPERO, CRD 42021257775.

Plasma amino acid profiling of cancer patients with abnormal Savda based on high-performance liquid chromatography

OBJECTIVE: To investigate metabolic signatures in plasma of cancer patients with abnormal Savda using plasma-free amino acid profiles, and to evaluate the diagnostic potential of these profiles for the detection and explanation of the mechanisms of different symptoms in traditional Uyghur medicine.METHODS: Plasma samples from cancer patients with abnormal Savda(n=85) or non-abnormal Savda(n=105) and a healthy control group(n=65)were analyzed using high-performance liquid chromatography(HPLC). Orthogonal projection to latent structures with discriminant analysis was used for the classification and prediction of abnormal Savda, and spectral profiles were subjected to Student's t-tests to assess statistical significance.RESULTS: Compared with the healthy group, the levels of aspartic acid, glutamate, glycine, histidine,arginine, threonine, alanine, proline, methionine,isoleucine, leucine and phenylalanine decreased significantly in plasma of cancer patients with abnormal Savda(all P<0.05). Serine, cystine, tyrosine,valine and lysine levels showed no significant differences(all P>0.05). Compared with non-abnormal Savda syndrome patients, abnormal Savda syndrome patients showed high concentrations of glutamate, serine, valine, isoleucine, leucine and phenylalanine(all P<0.05). The remaining plasma amino acids showed no significant differences(all P>0.05).CONCLUSION: Plasma-free amino acid profiling has the potential to assist in understanding and determining abnormal Savda. A HPLC-based metabonomic platform could be a powerful tool for the classification of symptoms in traditional medicine.

Validation of the predictive accuracy of"clinical+morphology nomogram"for the rebleeding risk of ruptured intracranial aneurysms after admission

Background:Rebleeding can cause a catastrophic outcome after aneurysmal subarachnoid hemorrhage.A clinical+morphology nomogram was promoted in our previous study to assist in discriminating the rupture intracranial aneurysms(RIAs)with a high risk of rebleeding.The aim of this study was to validate the predictive accuracy of this nomogram model.Method:The patients with RIAs in two medical centers from December 2020 to September 2021 were retrospectively reviewed,whose clinical and morphological parameters were collected.The Cox regression model was employed to identify the risk factors related to rebleeding after their admission.The predicting accuracy of clinical+morphological nomogram,ELAPSS score and PHASES score was compared based on the area under the curves(AUCs).Results:One hundred thirty-eight patients with RIAs were finally included in this study,20 of whom suffering from rebleeding after admission.Hypertension(hazard ratio(HR),2.54;a confidence interval of 95%(CI),1.01-6.40;P=0.047),bifurcation(HR,3.88;95%CI,1.29-11.66;P=0.016),and AR(HR,2.68;95%CI,1.63-4.41;P<0.001)were demonstrated through Cox regression analysis as the independent risk factors for rebleeding after admission.The clinical+morphological nomogram had the highest predicting accuracy(AUC,0.939,P<0.01),followed by the bifurcation(AUC,0.735,P=0.001),AR(AUC,0.666,P=0.018),and ELAPSS score(AUC,0.682,P=0.009).Hypertension(AUC,0.693,P=0.080)or PHASES score(AUC,0.577,P=0.244)could not be used to predict the risk of rebleeding after admission.The calibration curve for the probability of rebleeding showed a good agreement between the prediction through clinical+morphological nomogram and actual observation.Conclusion:Hypertension,bifurcation site,and AR were independent risk factors related to the rebleeding of RIAs after admission.The clinical+morphological nomogram could help doctors to identify the high-risk RIAs with a high predictive accuracy.

Early intervention improves clinical responses to seasonal allergic rhinitis by stimulation in sphenopalatine ganglion(Xinwu acupoint)

OBJECTIVE:To examine the efficacy of early intervention(4 weeks before pollen dispersal)with sphenopalatine ganglion(Xinwu acupoint)stimulation in patients with allergies after the onset of seasonal allergic rhinitis(SAR).METHODS:This is a prospective,randomized and unblinded half-open study.Forty-one SAR volunteers were randomly assigned to either the sphenopalatine ganglion(SPG)acupuncture plus supplementary acupuncture(SPG group)or the sham-SPG acupuncture plus supplementary acupuncture(SA group)stimulation 4 weeks before the onset of allergy season.The changes of the total nasal symptom score(TNSS)and the Rhinoconjunctivitis Quality of Life Questionnaire(RQLQ)scores were measured on the first week in the onset of allergy season.RESULTS:Four patients dropped out due to local hematoma and pain in the SPG and SA groups.The remaining 37 patients continued through to the end of the trial.After early intervention 4 weeks before the onset of allergy season,the sneezing,nasal congestion and itchiness scores in the first week of onset time were significantly lower in the SPG group than in the SA group patients(P<0.001).The RQLQ score obtained at the onset of symptoms indicated that symptoms were more significantly ameliorated in the SPG group than in the SA group(P<0.001).CONCLUSIONS:The results of this study confirmed that early intervention by sphenopalatine ganglion(Xinwu acupoint)stimulation can effectively improve the symptoms and the quality of SAR patients'daily lives.

Endovascular treatment with or without intravenous alteplase for acute ischaemic stroke due to basilar artery occlusion

Background and purpose It remains controversial if endovascular treatment(EVT)can improve the outcome of patients with acute basilar artery occlusion(BAO).This study aims to compare the functional outcomes between EVT with and without intravenous thrombolysis(IVT)first in patients who had acute ischaemic stroke(AIS)due to BAO.Methods Patients who had AIS with BAO who underwent EVT within 24 hours of onset were enrolled in this multicentre cohort study,and the efficacy and safety were compared between IVT+EVT and direct EVT.The primary outcome was 90-day functional independence.All outcomes were assessed with adjusted OR(aOR)from the multivariable logistic regression.In addition,a meta-analysis was performed on all recently published pivotal studies on functional independence after EVT in patients with BAO.Results Of 310 enrolled patients with BAO,241(78%)were treated with direct EVT and 69(22%)with IVT+EVT.Direct EVT was associated with a worse functional outcome(aOR,0.46(95%CI 0.24 to 0.85),p=0.01).IVT+EVT was associated with a lower percentage of patients who needed≥3 passes of stent retriever(10.14%vs 20.75%).The meta-analysis regression revealed a potential positive correlation between bridging with IVT first and functional independence(r=0.14(95%CI 0.05 to 0.24),p<0.01).Conclusions This study showed that compared with direct EVT,EVT with IVT first was associated with better functional outcomes in patients with BAO treated within 24 hours of onset.The meta-analysis demonstrated similar favourable efficacy of IVT first followed by EVT in patients with BAO.

Relationship between magnetic resonance imaging and molecular pathology in patients with glioblastoma multiforme

Background Glioblastoma multiforme （GBM） is the most common and lethal primary brain tumor in adults. Magnetic resonance imaging （MRI） is routinely used in the diagnosis, characterization and clinical management of GBM. The diagnosis and treatment of GBM is largely guided by histopathology and immunohistochemistry. This study aimed to identify the relationship between magnetic resonance features and molecular pathology of GBM. Methods MRI images of 43 glioblastoma patients were collected. Four imaging features, degree of edema, contrast tumor enhanced/T2 ratio, multiple lesions and tumor across the midline, were selected to identify their relationship with P53, Ki-67 and O6-methylguanine-DNA methltransferase （MGMT） expression in patients with GBM. The relationship between imaging features and molecular pathology was studied by chi-square test using the software SPSS 13.0. Results High expression of P53 was found correlated with low contrast tumor enhancedFF2 ratio, low expression of Ki-67 was correlated with multiple lesions and high expression of KI-67 may be related with tumor across the midline, low expression of MGMT was correlated with edema. Conclusion Some MRI features such as the degree of edema, contrast tumor enhanced/T2 ratio, multiple lesions and tumor acrossing the midline are correlated with P53, Ki-67 and MGMT of GBM.

Changes in the Vision-related Resting-state Network in Pituitary Adenoma Patients After Vision Improvement

Background：The aim of this research was to investigate the changes in the vision-related resting-state network （V-RSN） in pituitary adenoma （PA） patients after vision improvement,which was induced by operative treatment.Methods：Ten PA patients with an improved visual acuity or/and visual field after transsphenoidal pituitary tumor resection were recruited and underwent a complete neuro-ophthalmologic evaluation,as well as an magnetic resonance imaging （MRI） protocol,including structural and resting-state functional MRI sequences before and after the operation.The regional homogeneity （ReHo） of the V-RSN was evaluated.Two sample t-test was performed to identify the significant differences in the V-RSN in the PA patients before and after transsphenoidal pituitary tumor resection.Results：Compared with the preoperation counterparts,the PA patients with improved vision after the operation exhibited reduced ReHo in the bilateral thalamus,globus pallidus,caudate nucleus,putamen nucleus,supplementary motor area,and left hippocampal formation,and increased ReHo in the bilateral cuneus gyrus,calcarine gyrus,right lingual gyrus,and fusiform gyrus.Conclusions：PA patients with improved vision exhibit increased neural activity within the visual cortex,but decreased neural activity in subareas of the multisensory and multimodal systems beyond the vision cortex.

Differences in atheroma between Caucasian and Asian subjects with anterior stroke:A vessel wall MRI study

Background and purpose While extracranial carotid artery stenosis is more common among Caucasians and intracranial artery stenosis is more common among Asians,the differences in atherosclerotic plaque characteristics have not yet been extensively examined.We sought to investigate plaque location and characteristics within extracranial carotid and intracranial arteries in symptomatic Caucasians and Chinese using vessel wall MRI.Methods Subjects with recent anterior circulation ischaemic stroke were recruited and imaged at two sites in the USA and China using similar protocols.Both extracranial carotid and intracranial arteries were reviewed to determine plaque location and characteristics.Results The prevalence of extracranial carotid plaque in Caucasians and Chinese was 73.1%and 49.1%,respectively(p=0.055).Prevalence of intracranial plaque was 38.5%and 69.1%in Caucasians and Chinese,respectively(p=0.02).Furthermore,42% of Caucasians and 16%of Chinese had high-risk plaque(HRP)features(intraplaque haemorrhage,luminal surface disruption)in the extracranial carotid artery(p=0.03).The prevalence of HRP features in intracranial arteries was not significantly different between the two cohorts(4%vs 11%;p=0.42).Conclusions Differences in the location and characteristics of cerebrovascular atherosclerosis were identified by vessel wall MRI in US Caucasian and Chinese subjects with recent anterior circulation ischaemic stroke.Extracranial carotid plaques with HRP features were more common in Caucasians.Intracranial plaques were more common in Chinese subjects,but no significant difference between the two cohorts in intracranial HRP prevalence was found.Larger studies using vessel wall imaging to investigate racial differences in cerebrovascular disease may inform underlying mechanisms of HRP development and may ultimately help guide appropriate therapy.

Clinical practice guideline for body composition assessment based on upper abdominal magnetic resonance images annotated using artificial intelligence

Introduction Upper abdominal magnetic resonance(MR)imaging is appropriate for body composition analysis.111 Especially for individuals with obesity,it is of great value to quantify the hepatic proton density fat fraction(PDFF)and the amount of abdominal adipose tissue during clinical evaluation and for research on obesity-related risks.Analytical results may be used to determine the optimal choice of surgical procedure and evaluate treatment outcomes.Multiple artificial intelligence(Al)algorithms and systems have been developed for the automated measurement of body composition.The basis of Al development and application is to have uniform standards for clinical data acquisition and management.The uneven quality ofMR images is one ofthe major obstacles to Al system development and analytical results.A standardized process of MR scanning and clinical data management is urgently needed.