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.     

基于网络药理学和分子对接技术探讨黄芪干预腹膜纤维化的机制

目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。     

顶天立地服务需求 注重内涵创建一流——首都医科大学建校60周年教育教学与人才培养成果回顾

首都医科大学通过60年辛勤耕耘、精益求精，秉承“顶天立地”的人才培养理念，为社会培养了大批高水平的学术型与应用型医药卫生人才。回顾学校60年来本专科教育、全科医学教育、国际教育、研究生教育的人才培养成果，以总结经验并鼓舞全体首医人进一步求真务实、凝心聚力、积极进取、追求卓越，努力将学校建设成为国际一流的研究型医科大学。     

新型冠状病毒肺炎疫情对天津市无偿献血的影响及其对策

目的 分析新型冠状病毒肺炎(以下简称新冠肺炎)疫情对天津市无偿献血的影响.方法 回顾性分析该市2020年无偿献血人次及献血量,并与2019年献血情况进行对比;分析2020年春节前后及2019年同期的献血情况.结果 2020年捐献全血和单采血小板的总人次较2019年均下降13.03％,献血量分别下降17.60％、10.37％.2020年与2019年春节期间捐献全血和单采血小板的人次和献血量均明显下降,但2020年献血情况持续受疫情影响.2020年1-6月全血和单采血小板的献血情况较2019年同期下降较为明显,2020年7-12月的献血情况好转,与2019年同期差距减小.结论 新冠肺炎疫情对无偿献血工作提出严峻考验.常态化疫情防控期间,分析研判疫情对无偿献血工作的影响,有利于制订更有效的预防措施抗击疫情,保障临床用血.     

肠道菌群与恶性肿瘤的研究进展

人类微生物群是由寄生在人体上皮屏障的细菌和其他微生物组成的，其中大部分位于肠道内，与宿主之间形成共生的关系。机体肠道微生物的组成虽然受到年龄、饮食、生活方式等因素的影响，但在正常生理情况下是相对稳定的。近年来，肠道菌群与恶性肿瘤的关系越来越受到重视。肠道菌群不但能够维持局部稳态，还能调节机体代谢、炎症和免疫等生理过程。有研究表明，微生物群，特别是肠道菌群能够显著调节机体对癌症治疗的反应性以及机体对毒副反应的敏感性。检查肠道菌群中各菌种之间的比例可作为筛查恶性肿瘤的新方法。本文将综述微生物群具有影响肿瘤的发生发展、抗肿瘤治疗疗效以及药物不良反应的证据，以及其中所涉及的微生物种类，从而为恶性肿瘤精准治疗提供证据。     

不同手术方法治疗复杂胫骨平台骨折临床疗效观察

目的探讨不同手术方法治疗复杂胫骨平台骨折临床疗效。方法选择2016年1月—2018年12月84例复杂胫骨平台骨折患者,随机分组。单侧锁定钢板内固定组选择单侧锁定钢板内固定手术,双侧切口双侧解剖钢板内固定组选择双侧切口双侧解剖钢板内固定。分析手术操作时间、手术失血、平均住院天数以及复杂胫骨平台骨折愈合时间;治疗前后患者视觉模拟评分和Rasmussen膝关节功能评分;膝关节僵硬发生率。结果双侧切口双侧解剖钢板内固定组视觉模拟评分和Rasmussen膝关节功能评分、手术操作时间、手术失血、平均住院天数以及复杂胫骨平台骨折愈合时间、膝关节僵硬发生率和单侧锁定钢板内固定组比较有优势,P<0.05。结论复杂胫骨平台骨折患者实施双侧切口双侧解剖钢板内固定可获得较好效果。     

Real-World Palbociclib Use in HR+/HER2− Advanced Breast Cancer in Canada: The IRIS Study

Background: Palbociclib is a selective cyclin-dependent kinase (CDK) 4/6 inhibitor used in combination with aromatase inhibitors or fulvestrant for patients with hormone receptor-positive (HR+) human epidermal growth factor receptor 2 (HER2)-negative advanced/metastatic breast cancer (ABC/MBC). Palbociclib was the first CDK 4/6 inhibitor approved for HR+/HER2− ABC/MBC treatment in Canada in combination with letrozole (P+L) as an initial endocrine-based therapy (approved March 2016), or with fulvestrant (P+F) following disease progression after prior endocrine therapy (approved May 2017). The Ibrance Real World Insights (IRIS) study ({"type":"clinical-trial","attrs":{"text":"NCT03159195","term_id":"NCT03159195"}}NCT03159195) collected real-world outcomes data for palbociclib-treated patients in several countries, including Canada. Methods: This retrospective chart review included women with HR+/HER2− ABC/MBC receiving P+L or P+F in Canada. Physicians reviewed medical records for up to 14 patients, abstracting demographic and clinical characteristics, treatment patterns, and clinical outcomes. Progression-free rates (PFRs) and survival rates (SRs) at 6, 12, 18, and 24 months were estimated via Kaplan–Meier analysis. Results: Thirty-three physicians examined medical records for 247 patients (P+L, n = 214; P+F, n = 33). Median follow-up was 8.8 months for P+L and 7.0 months for P+F. Most patients were initiated on palbociclib 125 mg/d (P+L, 90.2%; P+F, 84.8%). Doses were reduced in 16.6% of P+L and 14.3% of P+F patients initiating palbociclib at 125 mg/d. The PFR for P+L was 90.3% at 12 months and 78.2% at 18 months; corresponding SRs were 95.6% and 93.0%. For P+F, 6-month PFR was 91.0%; 12-month SR was 100.0%. Conclusions: Dose reduction rates were low and PFR and SR were high in this Canadian real-world assessment of P+L and P+F treatments, suggesting that palbociclib combinations are well tolerated and effective.     

肝段或肝叶切除术对肝内胆管结石再次手术效果的影响

目的对比不同术式对肝内胆管结石再次手术效果，探讨肝段或肝叶切除术的优势。 方法回顾性分析2011年8月至2014年8月收治的79例肝内胆管结石再次手术患者资料，依据术式不同分为肝段(叶)切除术组(甲组，n＝38)和非肝段(叶)切除术组(乙组，n＝41)两组。应用SPSS 19.0软件对所有临床数据进行统计学分析，手术相关指标等以( ±s)的形式表示，组间比较采用独立t检验；术后并发症发生情况及预后情况等计数资料以例(%)的形式表示，采用χ²检验；P<0.05差异有统计学意义。 结果两组患者术中出血量、手术时间及术后住院时间相比，差异无统计学意义(P>0.05)；甲组患者的术后并发症发生率5.3%(2/38)显著低于乙组22.0%(9/41)(P<0.05)；甲组残留结石发生率、症状复发率2.6%(1/38)、 0(0/41)均显著低于乙组17.1%(7/41)、 12.2%(5/41)(P<0.05)，差异有统计学意义(P<0.05)；但两组患者的病死率2.6%(1/38)和0(0/41)相比，差异无统计学意义(P>0.05)。 结论肝段(叶)切除术能够有效改善肝内胆管结石再次手术效果，值得推广。