Quantification of myocardial fibrosis using noninvasive T2-mapping magnetic resonance imaging: Preclinical models of aging and pressure overload

Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T₂-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T₂-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T₂-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T₂ relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T₂ was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T₂ relaxation time was derived (R² = 0.98): T₂ (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T₂-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T₂-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.     

Efficacy and safety of cold snare polypectomy for sessile serrated polyps ≥ 10 mm: A systematic review and meta-analysis

BackgroundCold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.AimsWe aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.MethodsPubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.ResultsA total of 10 studies consisting of 1727 SSPs (range, 10–40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10–19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10–19 mm compared with those ≥20 mm (3.1% vs. 4.7%).ConclusionCSP was an effective and safe technique for removing SSPs ≥ 10 mm.     

Artificial intelligence and clinical data suggest the T cell-mediated SARS-CoV-2 nonstructural protein intranasal vaccines for global COVID-19 immunity

Advanced computational methodologies suggested SARS-CoV-2, nonstructural proteins ORF1AB, ORF3a, as the source of immunodominant peptides for T cell presentation. T cell immunity is long-lasting and compatible with COVID-19 pathology. Based on the supporting clinical data, nonstructural SARS-CoV-2 protein vaccines could provide global immunity against COVID-19.     

基于DTI评价急性缺血性脑卒中运动功能缺损程度与肾虚髓亏证的相关性研究＊

目的 运用核磁共振弥散张量成像技术（DTI），从皮质脊髓束损伤程度评价的角度，探讨肾虚髓亏证与急性缺血性脑卒中运动功能缺损程度相关性，丰富中风病病机及证候诊断，拓宽缺血性脑卒中的中医药防治思路，为急性缺血性脑卒中肾虚髓亏证患者运动功能损伤程度提供临床依据，强调肾虚髓亏证在急性缺血性脑卒中运动功能损伤中的重要意义。方法 纳入符合诊断标准的90例病例，根据证候分别归入肾虚髓亏组和非肾虚髓亏组，每组各45例。每组患者均给予常规西药治疗。对两组患者入院后行弥散张量成像检测，同时分别于治疗前及治疗后14天，记录两组患者NIHSS评分、改良Barthel指数量表及简化Fugl-Meyer运动功能评分量表评分，比较两组病例发病时的轻重程度及治疗前后两组病例组间的恢复差异。结果 研究显示，治疗前肾虚髓亏组在NIHSS评分方面高于非肾虚髓亏组（P<0.05）；治疗前肾虚髓亏组在改良Barthel指数量表及简化Fugl-Meyer运动功能评分方面低于非肾虚髓亏组（P<0.05）。治疗前后NIHSS评分、改良Barthel指数评分及简化Fugl-Meyer运动功能评分改善情况，非肾虚髓亏组要优于肾虚髓亏组（P<0.05）。治疗前两组患者在健侧内囊后肢及大脑脚外侧处FA值及ADC值无明显差异；肾虚髓亏组在患侧内囊后肢及大脑脚外侧处FA值及ADC值均低于非肾虚髓亏组（P<0.05）。相关性分析得出，两组患者患侧内囊后肢FA值与患者治疗前NIHSS评分呈负相关；两组患者患侧内囊后肢FA值与患者改良Barthel指数评分及简化Fugl-Meyer运动功能评分呈正相关；肾虚髓亏组患者患侧内囊后肢FA值与肾虚髓亏证中医证候评分呈负相关。结论 肾虚髓亏是急性缺血性脑卒中运动功能障碍的重要病机。研究结果显示，两组皮质脊髓束损伤程度与神经功能及运动功能损伤存在相关性，且肾虚髓亏组在皮质脊髓束的损伤程度方面与其中医证候评分呈负相关。     

Out of the boxes,out of the silos: The need of interdisciplinary collaboration to reduce poor-quality medical products in the supply chain

In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.     

Prospective characterization of incident hepatic steatosis in pediatric and adolescent patients after total pancreatectomy with islet autotransplantation

BackgroundHepatic steatosis has been described as a common finding in adults following total pancreatectomy with islet autotransplantation (TPIAT) but it is unknown if this occurs in children and adolescents.ObjectivesTo define the frequency of post-TPIAT hepatic steatosis in a sample of children and adolescents and to identify clinical predictors of incident steatosis post-TPIAT.MethodsIn this prospective study, consecutive participants at least 1-month post-TPIAT underwent a liver MRI with proton density fat fraction (PDFF) and blood draw at our pediatric academic medical center between April 2021 and January 2022. Comparison clinical pre-TPIAT liver MRI or ultrasound and insulin use and graft function data were extracted from the medical record. T-tests were used for the comparison of means across continuous variables between participants with and without post-TPIAT steatosis.ResultsA total of 20 participants (mean: 13 ± 4 years; 12 female) were evaluated. Mean liver PDFF at research MRI was 7.4 ± 6.2% (range: 2–25%). Seven participants (35%) had categorical hepatic steatosis (PDFF>5%) post-TPIAT, five of whom had pre-TPIAT steatosis, reflecting a 13% (2/15; 95% CI: 2–40%) incidence of post-TPIAT steatosis. Participant characteristics were not significantly different between subgroups with and without post-TPIAT steatosis. Mean PDFF at research MRI was not different between graft function subgroups (7.5% optimal/good vs. 7.3% marginal/failure; p = .96).ConclusionOur study shows a moderate prevalence but low incidence of hepatic steatosis in a small sample of children and adolescents post-TPIAT. This study raises questions about a causal relationship between TPIAT and hepatic steatosis.     

Étude de faisabilité : l’utilisation de l’imagerie médicale en éducation thérapeutique en radiothérapie

PurposeAssess the feasibility of a randomized controlled trial (RCT) exploring the use of medical imaging as a therapeutic education (TPE) intervention in external radiation therapy.Materials and methodsExperimental feasibility trial of “RCT” type carried out in a single-center, between November 2019 and March 2020, following adult patients treated by thoracic radiotherapy. In addition to the information usually given, the experimental group benefited from an intervention consisting in the visualization of their own medical images using the open-source software “Stone of Orthanc”.ResultsForty-nine patients were recruited with a refusal rate of 8.16% (4/49). 20 patients were withdrawn from the study for health reasons (COVID), 10 for medical reasons. All the remaining 15 participants completed the process. Although not significant, the experimental group showed a median gain in the perception of knowledge compared to the control group (+ 1.9 (1.6 – 2.2)) vs (+ 1.4 (1.4 – 1.8)), as well as a decrease in scores related to anxiety (? 3.0 (?4.5 - (?2.0)) vs ? 1.0 (?5.0 - 0.0)) and emotional distress ((? 5.0 (? 7.5 - (? 3.5)) vs (? 2.0 (? 5.0 - (? 1.0)) A significant reduction (p = 0.043) is observed for the depression score ((? 2.0 (?3.0 - (?1.5)) vs (0.0 (0.0 – 0.0)).ConclusionThis study demonstrates the feasibility of the project, with promising preliminary results. Some adaptations in order to conduct a larger-scale RCT are highlighted.