靶向MLL1-WDR5蛋白-蛋白相互作用抑制剂的研究进展

Mixed lineage leukemia 1(MLL1)是组蛋白甲基转移酶SET家族的成员之一。MLL1与WDR5、RbBP5、Ash2L和DPY-30组成MLL1甲基转移酶复合物调控组蛋白H3的第4位赖氨酸的甲基化水平，对造血系统的发育和血细胞的更新至关重要。部分白血病患者体内存在因MLL1基因易位而产生的致癌蛋白——MLL1融合蛋白，MLL1融合蛋白在发挥其致癌作用时需要功能完整的MLL1酶复合物，故靶向MLL1-WDR5的蛋白-蛋白相互作用成为治疗MLL1融合型白血病的潜在策略。本文对MLL1-WDR5蛋白-蛋白相互作用的生物学机制、结构信息以及抑制剂进行了系统的总结，并结合已报道数据对该领域进行了展望，以期为后续研究提供参考。     

Ex vivo porcine model for eye,eyelid, and orbit movement analysis of 4-mm ferromagnetic foreign bodies in MRI

Graefe's Archive for Clinical and Experimental Ophthalmology - Ferromagnetic foreign bodies (FFB) present during magnetic resonance imaging (MRI) explorations can lead to tissue injury due to...     

治伤巴布剂对大鼠急性软组织损伤模型P38MAPK、AKT信号通路的影响＊

目的 观察治伤巴布剂对急性软组织损伤（acute soft tissue injury， ASTI）模型p38丝裂原活化蛋白激酶（mitogen-activated protein kinase，MAPK）、丝/苏氨酸蛋白激酶（AKT）信号通路的影响，探讨治伤巴布剂干预ASTI的可能作用机制。方法 将40只雄性SD大鼠按照随机数字表法分为正常对照组、模型对照组、治伤巴布剂组、p38MAPK信号通路抑制剂组、AKT信号通路抑制剂组，每组8只。除正常对照组外，其余四组均予以左侧后肢小腿ASTI造模。造模成功后，治伤巴布剂组于标记部位立即予治伤巴布剂（修剪成1.5x3cm大小）外敷，并用胶布固定；其余四组均予等剂量赋形剂（修剪成1.5×3 cm大小）外敷处理，胶布固定；持续外敷，共持续24 h。p38MAPK信号通路抑制剂组在造模前30 min予腹腔注射p38MAPK信号通路抑制剂SB203580（400 μg/kg/天）1次；AKT信号通路抑制剂组在造模前30 min予腹腔注射AKT信号通路抑制剂perifosine（20 mg/kg/天）1次。分别于0（造模前）、2h、4h、8h、12h、24h测量受伤小腿肌肉处的周长，并计算肌肉肿胀率（muscle swelling rate，MSR）。24 h药物干预结束后，采用颈椎脱臼法处死大鼠。后将左侧后肢小腿损伤中心部位进行取材，分成三份。一部分用于观察组织病理学形态变化；一部分用于逆转录聚合酶链反应（RT-PCR）检测核因子-κB（nuclear factor kappa-B，NF-κB）p65 mRNA、肿瘤坏死因子-α（TNF-α）mRNA、白细胞介素-1β（IL-1β）mRNA表达水平；剩下部分用酶联免疫吸附试验（ELISA）法检测骨骼肌组织TNF-α、IL-1β含量水平及蛋白质免疫印迹（Western-blot）法测定p38MAPK、AKT、NF-κB p65、核因子抑制蛋白α（inhibitor kappa B alpha， IκBα）表达水平。结果 与正常对照组相比，模型对照组MSR显著增加（P<0.01）；病理形态学上，骨骼肌组织可见大面积肌细胞排列紊乱，肌细胞变性坏死，间质内可见红细胞聚集及大量炎症细胞浸润；骨骼肌组织TNF-α、IL-1β含量水平显著升高（P<0.01）；磷酸化p38MAPK（p-p38）/总p38MAPK（t-p38），磷酸化-AKT（p-AKT）/总-AKT（t-AKT）明显升高（P<0.01），NF-κB p65及NF-κB p65mRNA表达水平明显升高（P<0.01）。与模型对照组相比，治伤巴布剂组MSR在治疗第8 h、12 h、24 h显著下降（P<0.01），且在治疗第24 h，其MSR较p38MAPK、AKT信号通路抑制剂组下降更明显（P<0.05）；病理学评分显著下降（P<0.01），且较p38MAPK、AKT信号通路抑制剂组下降更显著（P<0.05）；骨骼肌组织TNF-α、IL-1β含量水平明显下降（P<0.01），且较p38MAPK、AKT信号通路抑制剂组更显著（P<0.05）；p-p38/t-p38及p-AKT/t-AKT明显下降（P<0.01），NF-κB p65及NF-κB p65 mRNA表达水平显著下降（P<0.01），且较p38MAPK、AKT信号通路抑制剂组在降低NF-κB p65及NF-κB p65 mRNA相对表达值方面更显著（P<0.01）。结论 治伤巴布剂可能同时对p38MAPK、AKT信号通路产生了一定的抑制作用，引起NF-κB活性下调，NF-κB p65蛋白的表达下调，进而引起骨骼肌组织TNF-α、IL-1β炎性细胞因子含量水平下调，减轻ASTI炎症反应，从而改善ASTI。     

利用酵母双杂交系统筛选NKD1结合蛋白质北大核心

目的:酵母双杂交技术筛选结肠癌细胞中与裸角质层同源蛋白1(naked cuticle homolog 1,NKD1)相互结合的蛋白质,从而进一步了解NKD1。方法:以结肠癌细胞SW480的cDNA为模板,克隆NKD1基因,并将其成功构建在pGBKT7诱饵载体上。利用酵母双杂交技术从结肠癌SW480细胞文库进行筛选。结果:初步筛选获得13个阳性克隆菌株。经测序,在数据库中BLAST比对后,共确定为8种不同基因编码的蛋白片段。回转实验进一步验证了这8种不同基因编码的蛋白均能够激活酵母双杂交系统中的His3、Ade2和LacZ报告基因。这8种不同基因中的4种基因编码的蛋白片段为YWHA蛋白家族成员,其中2种都是编码YWHAE蛋白片段。在结肠癌HCT116细胞中通过免疫共沉淀实验进一步验证,NKD1与YWHAE在结肠癌细胞中可以相互结合。结论:结肠癌细胞中,证实YWHAE是NKD1结合蛋白质,通过调控胰岛素的敏感性,进而调控结肠癌细胞对葡萄糖的摄入。     

Somatic hypermutation defects in two adult hyper immunoglobulin M patients

Immunologic Research - Hyper immunoglobulin M (HIGM) syndrome is a rare disorder of the immune system with impaired antibody functions. The clinical picture of the patients varies according to the...     

Defining minimum volume thresholds to increase quality of care: a new patient-oriented approach using mixed integer programming

A positive relationship between treatment volume and outcome quality has been demonstrated in the literature and is thus evident for a variety of procedures. Consequently, policy makers have tried to translate this so-called volume–outcome relationship into minimum volume regulation (MVR) to increase the quality of care—yet with limited success. Until today, the effect of strict MVR application remains unclear as outcome quality gains cannot be estimated adequately and restrictions to application such as patient travel time and utilization of remaining hospital capacity are not considered sufficiently. Accordingly, when defining MVR, its effectiveness cannot be assessed. Thus, we developed a mixed integer programming model to define minimum volume thresholds balancing utility in terms of outcome quality gain and feasibility in terms of restricted patient travel time and utilization of hospital capacity. We applied our model to the German hospital sector and to four surgical procedures. Results showed that effective MVR needs a minimum volume threshold of 125 treatments for cholecystectomy, of 45 and 25 treatments for colon and rectum resection, respectively, of 32 treatments for radical prostatectomy and of 60 treatments for total knee arthroplasty. Depending on procedure type and incidence as well as the procedure’s complication rate, outcome quality gain ranged between 287 (radical prostatectomy) and 977 (colon resection) avoidable complications (11.7% and 11.9% of all complications). Ultimately, policy makers can use our model to leverage MVR’s intended benefit: concentrating treatment delivery to improve the quality of care.

     

PREDICT-GTN 1: Can we improve the FIGO scoring system in gestational trophoblastic neoplasia?

Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.     

Study on the Value of Ultrasound Elastography Combined with Plasma miRNA Expression in the Early Detection of Breast Cancer

Background: Breast cancer (BC) is the most common malignant tumor in women, and its morbidity and mortality are increasing each year, due to the lack of specific clinical symptoms in the early stage of BC, and the lack of diagnostic methods for early breast cancer. Therefore, identifying an effective diagnostic method for early BC has become urgent. Materials and Methods: Breast lesions with a histological diagnosis that were examined by ultrasonic elastography (UE) in our department from June 2020 to December 2021 were reviewed. qRT-PCR was performed to measure the expression levels of miR-144-5p and miR-26b-5p in the plasma of patients with BC. The receiver operating characteristics (ROC) curve and area under the curve (AUC) were used to investigate the potential diagnostic value of miR- 144-5p, miR-26b-5p and the elastographic score in BC. Results: The ultrasonic elastography score(UES) was found to be significantly upregulated in BC compared with that in benign breast lesions, and the AUC, sensitivity and specificity were 0.809, 0.717 and 0.806 for distinguishing BC from benign breast lesions, respectively. miR-144-5p and miR-26b- 5p were found to be upregulated in the plasma of BC patients, and miR-144-5p+miR-26b-5p had 0.781 sensitivity and 0.780 specificity for the diagnosis of BC. Furthermore, we found that the diagnostic performance of miR-144-5p and miR-26b-5p combined with UES for BC had 0.913 sensitivity and 0.890 specificity. Conclusions: The combination of plasma miR-144-5p, miR-26b-5p and UES has a very high clinical application value for the early detection of BC.