肥厚型心肌病合并心房颤动患者射频消融术后心律失常复发心电指标的预测

目的:探讨心电指标f QRS与QTc联合是否能更好预测肥厚型心肌病(HCM)合并心房颤动患者导管消融术后的复发。方法:纳入在北京安贞医院行导管消融术的HCM合并心房颤动患者共120例(阵发/持续性心房颤动72/48)。消融策略包括:阵发性心房颤动患者行双侧肺静脉隔离(PVI);持续性心房颤动患者行PVI加左心房顶、二尖瓣峡部和三尖瓣峡部线性消融。术前评估基线心电图,f QRS定义为常规12导联心电图中至少两个连续导联的QRS波存在≥2个R波或者R波的波顶或S波的波谷出现顿挫波。采用Bazett公式校正QT间期。术后定期随访,复发定义为导管消融术后心电图或动态心电图记录的任何类型的>30 s的房性快速性心律失常。结果:59.2%(71/120)患者f QRR阳性。f QRS最常见于下壁导联(81.7%)。QTc间期(443.90±38.59)ms。平均随访13.4个月,窦性心律维持率为42.5%。多因素Cox回归分析表明,f QRS阳性(HR=1.922,95%CI:1.151~3.210,P=0.012)和QTc>448 ms(HR=1.982,95%CI 1.155~3.402,P=0.013)分别是术后复发的危险因素。f QRS和QTc联合能更好预测心房颤动术后复发。结论:f QRS和QTc延长是HCM合并心房颤动患者导管消融术后复发的独立预测因素。f QRS和QTc联合可用于预测该类患者心房颤动射频术后转归。     

黄芩素对胰腺导管腺癌作用机制的研究进展

胰腺癌是一种病死率极高的消化道恶性肿瘤,约90%为胰腺导管腺癌,和其他肿瘤一样,胰腺癌的侵袭转移是肿瘤患者死亡的主要原因。目前,由于临床上早期诊断困难,胰腺癌患者手术治疗的机率相较于其他消化道肿瘤低,化学治疗是继手术治疗后中晚期胰腺癌的主要治疗手段。由于化学治疗的不良反应逐渐增多,有必要寻求疗效好、毒副反应小的治疗方法和药物。中药以其药物来源广泛、临床应用历史悠久、多靶点协同作用等优点正成为抗肿瘤药物研究的热点。黄芩作为许多中药治疗胰腺癌的方剂配伍药材之一受到研究者的关注。黄芩素是主要来源于黄芩的黄酮类化合物,是目前证实的黄芩中具有抗炎、抗肿瘤活性的主要成分之一。文章对黄芩素在胰腺癌以及其他多种消化道肿瘤中抗肿瘤活性的研究现状及相关的作用及机制进行分析归纳,对黄芩、黄芩素的药物开发前景提出展望。     

From the Cover: Multigeneration analysis reveals the inheritance,specificity, and patterns of CRISPR/Cas-induced gene modifications in Arabidopsis

The CRISPR (clustered regularly interspaced short palindromic repeat)/Cas (CRISPR-associated) system has emerged as a powerful tool for targeted gene editing in many organisms, including plants. However, all of the reported studies in plants focused on either transient systems or the first generation after the CRISPR/Cas system was stably transformed into plants. In this study we examined several plant generations with seven genes at 12 different target sites to determine the patterns, efficiency, specificity, and heritability of CRISPR/Cas-induced gene mutations or corrections in Arabidopsis. The proportion of plants bearing any mutations (chimeric, heterozygous, biallelic, or homozygous) was 71.2% at T1, 58.3% at T2, and 79.4% at T3 generations. CRISPR/Cas-induced mutations were predominantly 1 bp insertion and short deletions. Gene modifications detected in T1 plants occurred mostly in somatic cells, and consequently there were no T1 plants that were homozygous for a gene modification event. In contrast, ∼22% of T2 plants were found to be homozygous for a modified gene. All homozygotes were stable to the next generation, without any new modifications at the target sites. There was no indication of any off-target mutations by examining the target sites and sequences highly homologous to the target sites and by in-depth whole-genome sequencing. Together our results show that the CRISPR/Cas system is a useful tool for generating versatile and heritable modifications specifically at target genes in plants.Genome engineering tools are important for plant functional genomics research and plant biotechnology. The CRISPR (clustered regularly interspaced short palindromic repeat)/Cas (CRISPR-associated) system has been successfully used for efficient genome editing in human cell lines, zebrafish, and mouse (1–3) and recently applied to gene modification in plants (4–10). In this system a short RNA molecule guides the associated endonuclease Cas9 to generate double strand breaks (DSBs) in the target genomic DNA, which lead to sequence mutations as a result of error-prone nonhomologous end-joining (NHEJ) DNA damage repair or to gene correction or replacement as a result of homology-dependent recombination (HR) (11). It was shown that engineered CRISPR/Cas caused mutations in target genes or corrections in transgenes in transient expression assays in plant protoplasts and tobacco leaves (10). Importantly, stable expression of the CRISPR/Cas in transgenic Arabidopsis, tobacco, and rice plants led to mutations (mostly indels) in target genes and correction of a transgene (4–9). However, it was not known whether the gene mutations and corrections occurred in somatic cells only or whether some of the mutations and corrections happened in germ-line cells and thus may be heritable. Additionally, it is unclear how specific the CRISPR/Cas is in plants. Previous studies in human cell lines indicated a high frequency of off-target effect of CRISPR/Cas-induced mutagenesis (12, 13) but a lower off-target effect in mice and zebrafish (14, 15). Here we show that the CRISPR/Cas-induced transgene correction or mutations in endogenous plant genes and transgenes detected in Arabidopsis T1 plants occurred mostly in somatic cells. However, some of the gene modifications were transmitted through the germ line and were heritable in Arabidopsis T2 and T3 plants following the classic Mendelian model. Mutations caused during DSB repair were predominantly 1 bp insertion and short deletions. Furthermore, our deep sequencing and analysis did not detect any off-targets in multiple CRISPR/Cas transgenic Arabidopsis lines, indicating that the mutagenesis effect of CRISPR/Cas is highly specific in plants.     

肝病患者血浆输注的现状

肝脏疾病的患者往往会伴随不同程度的凝血功能障碍和出血。成分血液中的血浆中含有大量的各种凝血因子,故血浆在肝病患者的治疗过程中起着不可替代的作用。为了解血浆在肝病中应用动态,为血浆在肝病中的临床应用提供参考,本文就国内外血浆在肝病中的应用作一概述。     

Effects of HMG-CoA Reductase Inhibitor on Experimental Autoimmune Myocarditis

Purpose  

Myocarditis is an acute inflammatory disease of the heart and is often a precursor of dilated cardiomyopathy. Experimental autoimmune myocarditis (EAM) has been used as a model for human myocarditis. The purpose of this study was to investigate the therapeutic role of 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitor, rosuvastatin, on the development of EAM.     

Dexamethasone induces osteogenesis via regulation of hedgehog signalling molecules in rat mesenchymal stem cells

Purpose

Hedgehog signalling plays an important role during the development of tissues and organs, including bone and limb. Dexamethasone (DEX), a synthetic and widely used glucocorticoid, affects osteogenesis of bone marrow mesenchymal stem cells (MSCs), while the signalling pathway by which DEX affects osteoblast differentiation remains obscure. This study aimed to investigate expressions of hedgehog signalling molecules Shh, Ihh and Gli1 during DEX-induced osteogenesis of rat MSCs in vitro.

Methods

DEX promoted osteoblast differentiation of MSCs at 10⁻⁸ mol/L from seven days to 21 days, demonstrated by enhancing alkaline phosphatase (ALP) activity and osteoblast-associated marker type I collagen expression during osteoblastic differentiation. Gene and protein expressions of hedgehog signalling molecules, Shh, Ihh and Gli1 were tested by RT-PCR and western blot analysis during osteoblast differentiation.

Results

Shh expression was increased compared to the control while Ihh and Gli1 expressions were decreased on both mRNA and protein level during DEX-induced osteoblast differentiation of MSCs from seven days to 21 days. Altogether, these data demonstrate that DEX can enhance Shh expression via a Gli1-independent mechanism during osteoblast differentiation of MSCs.

Conclusions

These results indicate that different patterns of hedgehog signalling are involved in DEX-induced osteogenesis and these findings provide insights into the mechanistic link between glucocorticoid-induced osteogenesis and hedgehog signalling pathway.     

Magnolol Attenuates Concanavalin A‐induced Hepatic Fibrosis,Inhibits CD4+ T Helper 17 (Th17) Cell Differentiation and Suppresses Hepatic Stellate Cell Activation: Blockade of Smad3/Smad4 Signalling

Magnolol is a pharmacological biphenolic compound extracted from Chinese herb Magnolia officinalis, which displays anti‐inflammatory and antioxidant effects. This study was aimed at exploring the potential effect of magnolol on immune‐related liver fibrosis. Herein, BALB/c mice were injected with concanavalin A (ConA, 8 mg/kg/week) up to 6 weeks to establish hepatic fibrosis, and magnolol (10, 20, 30 mg/kg/day) was given to these mice orally throughout the whole experiment. We found that magnolol preserved liver function and attenuated liver fibrotic injury in vivo. In response to ConA stimulation, the CD4⁺ T cells preferred to polarizing towards CD4⁺ T helper 17 (Th17) cells in liver. Magnolol was observed to inhibit Th17 cell differentiation in ConA‐treated liver in addition to suppressing interleukin (IL)‐17A generation. Hepatic stellate cells were activated in fibrotic liver as demonstrated by increased alpha smooth muscle actin (α‐SMA) and desmin. More transforming growth factor (TGF)‐β1 and activin A were secreted into the serum. Magnolol suppressed this abnormal HSC activation. Furthermore, the phosphorylation of Smad3 in its linker area (Thr179, Ser 204/208/213) was inhibited by magnolol. In vitro, the recombinant IL‐17A plus TGF‐β1 or activin A induced activation of human LX2 HSCs and promoted their collagen production. Smad3/Smad4 signalling pathway was activated in LX2 cells exposed to the fibrotic stimuli, as illustrated by the up‐regulated phospho‐Smad3 and the enhanced interaction between Smad3 and Smad4. These alterations were suppressed by magnolol. Collectively, our study reveals a novel antifibrotic effect of magnolol on Th17 cell‐mediated fibrosis.     

经阴道超声对剖宫产瘢痕子宫憩室的诊断

探讨经阴道超声对剖宫产后瘢痕子宫憩室的诊断价值。选取我院2012年1月至2016年3月收治的64例剖宫产切口处憩室的患者作为研究对象。取膀胱截石位,进行阴道常规纵切面、横切面超声扫查。观察子宫大小、形态、宫腔内积液、前壁下段剖宫产切口处回声、积液、局部是否有外凸、是否存在异常声像等。64例患者中,子宫切口憩室伴积血积液者56例,彩色多普勒超声显示憩室内和憩室周边没有看见明显的血流信号,经宫腔镜证实为子宫切口憩室。8例子宫切口憩室妊娠声像图显示子宫前壁下段剖宫产切口处有妊娠囊回声,4例看到卵黄囊,4例发现胎芽和胎心搏动。彩色多普勒超声显示妊娠囊周边有丰富的血流信号。4例经宫腔镜检查确诊,4例为其他医院人工流产后出血多转入我院后手术确诊。经阴道超声对剖宫产瘢痕子宫憩室有较高诊断价值,可辅助临床诊断。     

1H-MR波谱检测腓肠肌细胞内脂质浓度用于早期诊断2型糖尿病模型大鼠周围神经病变

目的 观察¹H-MR波谱(MRS)检测腓肠肌肌细胞内脂质(IMCL)浓度对早期诊断2型糖尿病(T2DM)模型大鼠周围神经病变(DPN)的价值。方法 将30只雄性SD大鼠随机分为糖尿病(DM)组和正常组,每组15只。对DM组以高糖高脂饲养4周联合单次腹腔注射1%链脲佐菌素(STZ)溶液45 mg/kg体质量建立T2DM模型,正常组则以普通饲料饲养4周联合注射1% STZ柠檬酸-柠檬酸钠缓冲液作为对照。于建模成功后第4、8周采集2组大鼠右后肢腓肠肌¹H-MRS,检测其IMCL浓度;于建模成功后第8周处死动物,检测2组右坐骨神经运动神经传导速度(MNCV)和感觉神经传导速度(SNCV),之后行病理学检查,观察坐骨神经组织变化,判断是否发生DPN;评估腓肠肌IMCL浓度对早期诊断DPN的价值。结果 DM组15只均成功建立T2DM大鼠模型,建模成功后每周DM组大鼠空腹血糖及体质量均高于正常组(P均＜0.05)。建模成功后第4、8周,DM组大鼠右后肢腓肠肌IMCL浓度均显著高于正常组(P均＜0.01),且建模成功后第8周DM组及正常组大鼠IMCL浓度均明显高于第4周(P均＜0.01)。建模成功后第8周,DM组大鼠均发生DPN,其右坐骨神经MNCV及SNCV均明显低于正常组(P 均＜0.001);病理结果示神经纤维异常变化。结论 ¹H-MRS检测腓肠肌IMCL对早期诊断T2DM大鼠DPN具有一定价值。     

脂多糖诱导C57BL/6J小鼠急性炎症对听力损失的影响

目的 采用脂多糖(LPS)腹腔注射的方法诱导C57BL/6J小鼠机体产生急性炎症,观察急性炎症期小鼠听力情况,并分析其相关机制。方法 将C57BL/6J小鼠30只随机分为空白组、LPS组及对照组,每组10只,LPS组予以2.5 mg/kg的LPS,对照组输注相等体积的生理盐水,其余生活条件保持一致。注射LPS 3、7、15 d后,通过听性脑干反应(ABR)评估小鼠听力情况。冰冻耳蜗组织切片HE染色观察耳蜗组织形态学变化。ELASA方法观察小鼠体内TNF-α、IL-1β、IL-6的变化。同时观测小鼠饮水、饮食及体质量的变化。结果 与对照组比较,LPS组在注射3、7 d后的听力阈值均明显升高,P<0.05,但是注射15 d后两组听力阈值比较,差异无统计学意义,其余频率下阈值变化不明显。注射LPS 3 d后,LPS组的TNFα,IL-6及NF-κB水平明显高于对照组,P<0.05,IL-1β无明显变化。LPS组螺旋神经节细胞有丢失,血管纹部分空泡化,形态异常。但是,LPS不影响小鼠的饮食饮水及体质量。结论 LPS可以引发小鼠耳蜗急性炎症,造成听力损失,主要表现为高频听力损失。