Rhabdoid tumor predisposition syndrome with renal tumor 10 years after brain tumor

We report a case of rhabdoid tumor predisposition syndrome with a renal tumor developing 10 years after a brain tumor, which demonstrated an unexpectedly favorable outcome. A 2-year-old boy underwent gross total resection of a brain tumor located in the fourth ventricle, and received adjuvant chemotherapy and radiotherapy. At the age of 11 years, a renal tumor was found and nephrectomy was performed. He is currently alive without evidence of disease over 2 years without postoperative therapy. Histologically, rhabdoid cells were observed in both brain and renal tumors. Loss of SMARCB1 (also known as INI1) expression was found in the nucleus of both tumor cells. Genetic testing revealed pathogenic variants of SMARCB1 exon 5 in the renal tumor and SMARCB1 exon 9 in the brain tumor. In addition, heterozygous deletion of 22q11.21-q11.23 containing the SMARCB1 locus was shared by both tumors and this deletion was identified in normal peripheral blood. Considering the histopathological and genetic findings, our case was considered to be rhabdoid tumor predisposition syndrome with atypical teratoid/rhabdoid tumor and late-onset rhabdoid tumor of the kidney.     

肺动脉高压对右心重构及右心室AT_1R、TGF-β1、ERK1/2蛋白表达的实验研究

目的:探讨肺动脉高压(pulmonary arterial hypertension,PAH)对大鼠右心重构及右心室AT1R,TGF-β1及ERK1/2蛋白的表达。方法:选取体质量250~260g的健康雄性SD大鼠12只,随机分为:对照组(n=6)、PAH右心重构组(n=6)。对照组和PAH右心重构组分别予以0.9%氯化钠液和野百合碱(MCT)60 mg/kg单次注射于大鼠颈背部皮下,饲养6w建立模型。应用超声生物显微镜测定其右心室前壁厚度(RVAWd)及右心室射血分数(RVEF),应用右心导管测定肺动脉平均压(mPAP)。处死后分别称量右心室(RV)和左心室+室间隔(LV+SP)质量,计算右心室肥厚指数(RVHI)。天狼猩红染色计算心肌组织胶原容积分数(CVF)。应用Western blot测定右心室AT1R,TGF-β1,ERK1/2蛋白表达。结果:与对照组相比,野百合碱诱导6w后,PAH右心重构组的RVAWd、mPAP、RVHI及CVF均高于对照组,差异有统计学意义,分别为RVHI[(25.01±1.20)vs.(40.57±4.17)%],mPAP[(16.56±1.98)vs.(29.46±2.47)mmHg],RVAWd[(0.65±0.09)vs.(1.17±0.08)mm],RVEF[(54.15±4.60)vs.(62.63±9.54)%],均为P0.01;PAH右心重构组右心室心肌组织AT1R、TGF-β1及ERK1/2蛋白表达显著高于对照组(均为P0.05)。结论:肺动脉高压对大鼠右心重构及右心室AT1R、TGF-β1及ERK1/2蛋白表达显著上调。     

Measurement of thrombin generation intra-operatively and its association with bleeding tendency after cardiac surgery

Introduction

Patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) are susceptible to haemostatic disturbances. Monitoring the haemostatic capacity by conventional clotting tests is challenging.

Materials and Methods

Thrombin generation (TG) by Calibrated Automated Thrombography, clotting tests and tissue factor pathway inhibitor (TFPI) measurements were performed to describe the relationship between haemostatic changes and alterations in these tests. Blood samples were collected before, during and after CPB. Furthermore, it was investigated whether TG measured intraoperatively, is associated with increased risk of bleeding postoperatively.

Results

TG diminished significantly (p < 0.01) after heparinization in the presence and absence of platelets (37% and 50%) compared to baseline. After the start of CPB, TG elevated and persisted till the end of surgery but remained lower than preoperatively. Activated clotting time increased after heparinization and after the start of bypass compared to baseline (400% and 500%). Anti-FXa activity reduced on the start of CPB compared to the level after heparinization, to almost the baseline value following protamine reversal of heparin. The plasma levels of total and free TFPI elevated 9 and 14 fold during bypass and remained after protamine administration higher than preoperatively. Plasma D-dimer levels reduced (p < 0.01) when bypass started. However, a marked elevation was observed in the following time points. TG in platelet-rich plasma measured after heparinization and after the start of CPB associated (p < 0.05) with postoperative blood loss.

Conclusions

TG can be determined during CPB despite the high heparinization level, it reflects the haemostatic capacity better than clotting-based assays and might better predict bleeding when performed intraoperatively.     

Tamoxifen induces resistance to activated protein C

Introduction

The estrogen antagonist tamoxifen (TAM) increases the thrombotic risk similar to estrogen containing oral contraceptives (OC). In OC users this risk is attributed to alterations of hemostasis resulting in acquired resistance to activated protein C (APC). TAM-induced APC resistance has not been reported yet.

Materials and Methods

Blood samples were collected prospectively from women with breast cancer before (n = 25) and monthly after start of adjuvant TAM treatment (n = 75). APC resistance was evaluated on basis of the effect of APC on the endogenous thrombin generation potential. To detect increased in vivo APC generation APC plasma levels were measured using a highly sensitive oligonucleotide-based enzyme capture assay. Routine hemostasis parameters were measured additionally.

Results

APC sensitivity decreased by 41% (p = 0.001) compared to baseline after one month of TAM application and remained significantly decreased during the study period. Free protein S increased (p = 0.008) while other analyzed procoagulant factors, inhibitors, and activation markers of coagulation decreased or did not change significantly. In five patients the APC concentration increased to non-physiological levels but an overall significant increase of APC was not observed.

Conclusions

This is the first study showing acquired APC resistance under TAM therapy. Acquired APC resistance might explain the increased thrombotic risk during TAM treatment. Observed changes of hemostasis parameters suggest different determinants of TAM-induced APC resistance than in OC-induced APC resistance. The presence of acquired APC resistance in TAM patients warrants further evaluation if these patients may benefit from antithrombotic prophylaxis in the presence of additional thrombotic risk factors.     

Evaluation and performance characteristics of the Q Hemostasis Analyzer, an automated coagulation analyzer

The Q Hemostasis Analyzer (Grifols, Barcelona, Spain) is a fully-automated random-access multiparameter analyzer, designed to perform coagulation, chromogenic and immunologic assays. It is equipped with a cap-piercing system. The instrument was evaluated in a hemostasis laboratory of a University Hospital with respect to its technical features in the determination of coagulation i.e. prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time, fibrinogen and single coagulation factors V (FV) and VIII (FVIII), chromogenic [antithrombin (AT) and protein C activity] and immunologic assays [von Willebrand factor antigen (vWF:Ag) concentration], using reagents from the analyzer manufacturer. Total precision (evaluated as the coefficient of variation) was below 6% for most parameters both in normal and in pathological ranges, except for FV, FVIII, AT and vWF:Ag both in the normal and pathological samples. No carryover was detected in alternating aPTT measurement in a pool of normal plasma samples and in the same pool spiked with unfractionated heparin (> 1.5 IU/mL). The effective throughput was 154 PT, 66 PT/aPTT, 42 PT/aPTT/fibrinogen, and 38 PT/aPTT/AT per hour, leading to 154 to 114 tests performed per hour, depending of the tested panel. Test results obtained on the Q Hemostasis Analyzer were well correlated with those obtained on the ACL TOP analyzer (Instrumentation Laboratory), with r between 0.862 and 0.989. In conclusion, routine coagulation testing can be performed on the Q Hemostasis Analyzer with satisfactory precision and the same apply to more specialized and specific tests.     

The lowest VE/VCO2 ratio best identifies chronic thromboembolic pulmonary hypertension

Introduction

The natural history of acute pulmonary embolism (PE) under treatment is about a gradual resolution of the thrombi, and uncommonly, the development of chronic thromboembolic pulmonary hypertension (CTEPH). We hypothesized that ventilatory efficiency parameters during cardiopulmonary exercise testing (CPET) may be able to monitor the process and predict CTEPH.

Methods

15 patients rehabilitated from acute PE (total resolution of thrombi), 44 patients with chronic PE (with residual thrombi), 66 patients with CTEPH, and 36 sedentary healthy controls performed incremental CPET.

Results

The lowest VE/VCO₂ was higher in CTEPH patients than that in chronic PE and rehabilitated patients (43.4 L/min vs 29.9 L/min vs 27.1 L/min, p < 0.005). The VE/VCO₂ slope (48.4 L/min/L/min vs 29.9 L/min/L/min vs 28.0 L/min/L/min, p < 0.005) and oxygen uptake efficiency plateau (OUEP) (37.1 L/min vs 27.0 L/min vs 25.2 L/min, p < 0.005) had the similar changes. In logistic regression analysis, the lowest VE/VCO₂ ≥ 34.35 L/min was the best predictor of CTEPH (OR 159.0, 95% CI 36.0-702.3, p < 0.001). The lowest VE/VCO₂ was higher in chronic PE patients compared with the controls (29.9 L/min vs 26.5 L/min, p < 0.05), but there was no difference between the rehabilitated patients and the controls. In multiple linear regression analysis, the percentage of vascular obstruction by ventilation-perfusion lung scanning (PVO) was the most significant independent predictor for indices of ventilatory efficiency in chronic PE and rehabilitated patients.

Conclusions

CTEPH is associated with weakened ventilatory efficiency. The lowest VE/VCO2 ratio has the best capability to predict CTEPH. Ventilatory inefficiency improves along with recovery of acute PE.     

71例阵发性房性心动过速的动态心电图分析与探讨

目的：探讨71例阵发性房性心动过速发生规律及其临床意义。方法 ：应用动态心电图对71例短阵房性心动过速发生规律及其昼夜节律进行监测与分析。结果：房性心动过速以冠心病发生率最高（49.3%）;检出率随年龄增长而增加,老年组检出率最高,尤以男性发生率增加更为明显,与其他年龄组比较差异有统计学意义（P〈0.01）;老年组房性心动过速昼夜节律减弱。结论：冠心病患者受到心房肌缺血、缺氧、炎症、变性、纤维化等多种因素的影响,使心房肌除极速度不一致,利于短阵房性心动过速的发生;短阵房性心动过速的检出率随年龄增长呈上升趋势,主要因素与心肌退行性病变引起心脏自律性、兴奋性及传导性发生改变有关;房性心动过速昼夜节律减弱,提示老年人房性心动过速多为病理性改变。     

TNF-α对培养乳鼠心肌细胞的作用

目的:探讨不同浓度肿瘤坏死因子-α(TNF-α)对培养的乳鼠心肌细胞活力、蛋白合成、分泌AngⅡ及AT1受体表达的影响。方法: 体外培养的SD乳鼠心肌细胞随机分为对照组和不同浓度TNF-α（20、40、60、80、100 μg/L）干预组,用BCA法测定心肌细胞蛋白合成总量,MTT比色法和LDH检测反映心肌细胞的活力,ELISA法检测心肌细胞培养液中AngⅡ的含量,免疫细胞化学染色法检测心肌细胞膜AT1受体表达的变化。结果: TNF-α浓度依赖性地增强乳鼠心肌细胞活力、增加蛋白合成,20、40、60、80 μg/L TNF-α组细胞活力较对照组分别增加1.21（P<0.05)、1.42、1.51和1.73倍（均P<0.01),蛋白合成分别增加27.8%（P<0.05）、38.9%、46%和66.7%（均P<0.01）,而LDH含量差异无显著性。100 μg/L TNF-α组与对照组比较,心肌细胞活力降低18.5%（P<0.01）、蛋白合成降低18.3%（P<0.01）及心肌LDH生成增加1.48倍（P<0.01)。TNF-α浓度依赖性地增加乳鼠心肌细胞AngⅡ分泌,与对照组比较分别增加0.5、1.1、1.6、3和3.6倍（均P<0.01）。TNF-α还具有诱导AT1受体的表达的作用。结论: TNF-α可促进心肌细胞内源性AngⅡ产生,引起心肌细胞活力、蛋白合成改变,AT1受体表达上调,可能介导了心肌肥大、心肌受损等心肌改建的病理生理过程。