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141.
142.
Alloimmunization is the major complication of platelet transfusion therapy in patients with acute leukemia. To evaluate whether alloimmunization continues to be a long-term problem in patients surviving induction therapy, 114 patients with acute nonlymphocytic leukemia (ANLL) who survived more than 6 mo and who received multiple courses of chemotherapy and abundant platelet transfusions were studied. Clinical response to random donor platelets and lymphocytotoxic antibody (LCTAb) were measured pretreatment and serially throughout the study period. Fourteen patients (12%) were alloimmunized upon admission, 34 (30%) patients became alloimmunized during remission induction therapy, and 66 (58%) patients did not become alloimmunized during that period. Sixty-one of these 66 patients (92%) never became alloimmunized and responded to random donor platelets during their subsequent course despite the fact they received multiple further platelet transfusions, whereas the alloimmunized patients tended to remain alloimmunized for their entire clinical course. There was no difference in age or sex between groups, and prognostic factors predicting alloimmunization could not be detected. In greater than 90% of patients not alloimmunized at admission, the presence or absence of LCTAb after induction predicts later alloantibody production. This information can be used to plan the type of platelet transfusions (HLA-matched or random donor) needed for subsequent maintenance and induction therapy. It may also help to identify a group of patients to whom more aggressive maintenance chemotherapy may be more safely administered. 相似文献
143.
Marleen Straat Marcella CA Müller Joost CM Meijers Mendi S Arbous Angelique ME Spoelstra - de Man Charlotte JP Beurskens Margreeth B Vroom Nicole P Juffermans 《Critical care (London, England)》2015,19(1)
IntroductionMuch controversy exists on the effect of a fresh frozen plasma (FFP) transfusion on systemic inflammation and endothelial damage. Adverse effects of FFP have been well described, including acute lung injury. However, it is also suggested that a higher amount of FFP decreases mortality in trauma patients requiring a massive transfusion. Furthermore, FFP has an endothelial stabilizing effect in experimental models. We investigated the effect of fresh frozen plasma transfusion on systemic inflammation and endothelial condition.MethodsA prospective predefined substudy of a randomized trial in coagulopathic non-bleeding critically ill patients receiving a prophylactic transfusion of FFP (12 ml/kg) prior to an invasive procedure. Levels of inflammatory cytokines and markers of endothelial condition were measured in paired samples of 33 patients before and after transfusion. The statistical tests used were paired t test or the Wilcoxon signed-rank test.ResultsAt baseline, systemic cytokine levels were mildly elevated in critically ill patients. FFP transfusion resulted in a decrease of levels of TNF-α (from 11.3 to 2.3 pg/ml, P = 0.01). Other cytokines were not affected. FFP also resulted in a decrease in systemic syndecan-1 levels (from 675 to 565 pg/ml, P = 0.01) and a decrease in factor VIII levels (from 246 to 246%, P <0.01), suggestive of an improved endothelial condition. This was associated with an increase in ADAMTS13 levels (from 24 to 32%, P <0.01) and a concomitant decrease in von Willebrand factor (vWF) levels (from 474 to 423%, P <0.01).ConclusionsA fixed dose of FFP transfusion in critically ill patients decreases syndecan-1 and factor VIII levels, suggesting a stabilized endothelial condition, possibly by increasing ADAMTS13, which is capable of cleaving vWF.
Trial registrations
Trialregister.nl NTR2262, registered 26 March 2010 and Clinicaltrials.gov , registered 14 June 2010. NCT01143909相似文献144.
目的 探讨热休克蛋白72肽结合区在肾小管上皮间质转分化(EMT)过程中的作用和可能机制.方法 应用质粒转染方法分别诱导热休克蛋白72(HSP72)野生型、肽结合区缺失型(HSP72-△PBD)和肽结合区(PBD)的表达.用转化生长因子β1(TGF-β1)刺激大鼠肾小管上皮细胞(NRK-52E)48 h,Western印迹和免疫荧光染色检测细胞E-钙黏蛋白(cadherin),α-平滑肌肌动蛋白(SMA),HSP72和Smad3/磷酸化(p)-Smad3蛋白表达.结果 TGF-β1(10 μg/L)刺激NRK-52E细胞48 h后上调α-SMA和下调E-cadherin蛋白表达水平.Western印迹及细胞免疫荧光显示,过表达HSP72和PBD能明显减轻TGF-β1诱导的NRK-52E细胞E-cadherin蛋白表达下调和α-SMA蛋白表达上调,而过表达HSP72-△PBD不能改变上述蛋白的表达.此外,过表达HSP72和PBD显著抑制Smad3的磷酸化.结论 HSP72抑制Smad3活化和EMT的发生可能与PBD的功能有关. 相似文献
145.
Marcella CA Müller Kirsten Balvers Jan M Binnekade Nicola Curry Simon Stanworth Christine Gaarder Knut M Kolstadbraaten Claire Rourke Karim Brohi J Carel Goslings Nicole P Juffermans 《Critical care (London, England)》2014,18(6)
Introduction
Data on the incidence of a hypercoagulable state in trauma, as measured by thromboelastometry (ROTEM), is limited and the prognostic value of hypercoagulability after trauma on outcome is unclear. We aimed to determine the incidence of hypercoagulability after trauma, and to assess whether early hypercoagulability has prognostic value on the occurrence of multiple organ failure (MOF) and mortality.Methods
This was a prospective observational cohort study in trauma patients who met the highest trauma level team activation. Hypercoagulability was defined as a G value of ≥11.7 dynes/cm2 and hypocoagulability as a G value of <5.0 dynes/cm2. ROTEM was performed on admission and 24 hours later.Results
A total of 1,010 patients were enrolled and 948 patients were analyzed. Median age was 38 (interquartile range (IQR) 26 to 53), 77% were male and median injury severity score was 13 (IQR 8 to 25). On admission, 7% of the patients were hypercoagulable and 8% were hypocoagulable. Altogether, 10% of patients showed hypercoagulability within the first 24 hours of trauma. Hypocoagulability, but not hypercoagulability, was associated with higher sequential organ failure assessment scores, indicating more severe MOF. Mortality in patients with hypercoagulability was 0%, compared to 7% in normocoagulable and 24% in hypocoagulable patients (P <0.001). EXTEM CT, alpha and G were predictors for occurrence of MOF and mortality.Conclusions
The incidence of a hypercoagulable state after trauma is 10% up to 24 hours after admission, which is broadly comparable to the rate of hypocoagulability. Further work in larger studies should define the clinical consequences of identifying hypercoagulability and a possible role for very early, targeted use of anticoagulants.Electronic supplementary material
The online version of this article (doi:10.1186/s13054-014-0687-6) contains supplementary material, which is available to authorized users. 相似文献146.
Effects of recombinant human granulocyte-macrophage colony-stimulating factor on intracellular pH in mature granulocytes 总被引:1,自引:0,他引:1
Sullivan R; Griffin JD; Wright J; Melnick DA; Leavitt JL; Fredette JP; Horne JH Jr; Lyman CA; Lazzari KG; Simons ER 《Blood》1988,72(5):1665-1673
We studied the effects of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSFrh) on the internal pH of granulocytes using the fluorescent probe BCECF. GM-CSFrh did not directly alter the resting pH of granulocytes isolated from the peripheral blood; however, when the cells were preincubated for 90 minutes with the growth factor and then activated with the chemotactic peptide N-formyl met leu phe (fMLP), they exhibited both an acceleration in the initial rate of acidification and a marked delay in realkalinization. The kinetic changes both in initial acidification and in subsequent realkalinization induced by GM-CSFrh priming were not prevented by protein synthesis inhibitors and were observed in granulocytes harvested from patients with both sex-linked and autosomal recessive chronic granulomatous disease (CGD). By directly quantitating H+ ion secretion, by monitoring the effects of sodium repletion on intracellular pH, and through use of the sodium channel inhibitors amiloride and dimethyl amiloride and the Na+/K+-ATPase inhibitor ouabain, we showed that the altered kinetics of intracellular acidification and alkalinization following fMLP stimulation of GM-CSFrh- primed granulocytes could not be accounted for by changes in transmembrane proton exportation regulated by the Na+/H+ antiport channel. Although the initial acidification following fMLP was abrogated by 2-deoxy-D-glucose in both GM-CSFrh-pretreated and GM-CSFrh- untreated granulocytes, retardation of the subsequent phase of alkalinization was observed in GM-CSFrh-primed cells even after inhibition of both glycolytic and mitochondrial metabolism. Our data indicate that the increased cytosolic acidification following fMLP stimulation in granulocytes "primed" with GM-CSFrh does not result from disordered proton excretion but instead from increased release of intracellular free acid which is only partially coupled to glucose catabolism or to the generation of superoxide anion (O2-). 相似文献
147.
Serial evaluations of lymphocytotoxic antibody (LCTAb) and responsiveness to random donor platelet transfusion were reviewed in 234 patients who had developed LCTAb at some time during their treatment course. Seventy (30%) of these patients had significant falls in antibody levels. In 44 patients these declines occurred after further antigenic exposure was reduced either because no transfusions were administered or only histocompatible platelets were transfused. Forty patients with declines in LCTAb levels who were previously refractory to platelet transfusion were rechallenged with random donor platelets. Thirty-four of 35 clinically evaluable patients had good responses to these unmatched transfusions for 2 weeks to 36 months, and in 21 patients antibody did not return despite repeated transfusions. Thus, serial LCTAb measurements are helpful in the management of alloimmunized patients. Many patients will have decreases or a loss of LCTAb, either permanently or transiently, and can be successfully supported with more easily available unmatched random donor platelet transfusions. 相似文献
148.
Monocyte-mediated antibody-dependent cell-mediated cytotoxicity: the role of the metabolic burst 总被引:4,自引:0,他引:4
Human monocytes respond to opsonized microorganisms with a "metabolic burst" composed of an increase in oxygen consumption, an increase in hexose monophosphate shunt (HMPS) activity, and the generation of reactive oxygen species (ROS). We investigated the role of the metabolic burst in antibody-dependent cell-mediated cytotoxicity (ADCC) by human monocytes toward anti-D coated erythrocyte target cells because recent studies suggested a role for oxygen-dependent bactericidal mechanisms in ADCC. In normal monocytes, we found that ADCC was nearly halved under hypoxic conditions. Several agents known to impair activation of the burst, such as vincristine, cation chelators, and a sulfhydryl reagent, all decreased cytotoxicity if added before initiation of contact between target and effector cells. Cytotoxicity was inhibited by 2-deoxyglucose but not fluoride, suggesting a nonglycolytic role for glucose in ADCC, perhaps in the HMPS pathway. Although these data suggested a role for the metabolic burst in ADCC, scavengers of ROS did not impair cytotoxicity, and monocytes from chronic granulomatous disease (CGD) patients who had a defective metabolic burst had normal levels of ADCC. We conclude that ADCC toward anti-D coated erythrocyte target cells was the result of at least two independent but closely related cytotoxic pathways. Although one of these pathways appeared to involve the metabolic burst, the potentially cytotoxic reactive oxygen species did not appear to play a role in this system. 相似文献
149.
目的探讨CpG岛甲基子表型阳性的散发性大肠癌的基因表达特征。方法对71例散发性大肠癌采用甲基化特异性PCR法行p14ARF、人类mut-s同系物1(hMLH1)、p16INK4a、6-氧-甲基鸟嘌呤-DNA甲基转移酶(MGMT)和肿瘤甲基化位点1(MINT1)共5个基因启动子甲基化的检测,确定CpG岛甲基子表型;进行K-ras、APC、P53、Bax和转化生长因子βⅡ受体(TGFβRⅡ)共5个基因的免疫组化检测。分析散发性大肠癌CpG岛甲基子表型和基因表达之间的关系。结果71例散发性大肠癌中,CpG岛甲基子表型阳性率为21.1%(15/71);K-ras、APC、P53、Bax和TGFβRⅡ蛋白阳性表达率分别为43.7%(31/71)、42.3%(30/71)、47.9%(34/71)、71.4%(50/70)和59.2%(42/71)。CpG岛甲基子表型和APC、P53、Bax、TGFβRⅡ蛋白表达均无显著相关性,但与K-ras蛋白表达显著相关,CpG岛甲基子表型阳性者K-ras蛋白阳性表达率显著高于CpG岛甲基子表型阴性者(66.7%比37.5%, P=0.043)。结论CpG岛甲基子表型阳性的散发性大肠癌中K-ras蛋白呈高表达,提示多基因同时甲基化与K-ras蛋白的激活表达密切相关,两者的关系表明表遗传学机制可以间接引起遗传学改变。 相似文献
150.
RR Klont CA Eggink AJ Rijs P Wesseling PE Verweij 《Clinical infectious diseases》2005,40(12):e110-e112
A case of invasive Fusarium keratitis in a previously healthy male patient was treated successfully with cornea transplantation and systemic and topical voriconazole after treatment failure with topical amphotericin B and systemic itraconazole. Topical voriconazole was well tolerated, and, in conjunction with the oral administration, it resulted in a high level of the drug in the anterior chamber of the eye (which was 160% of the plasma drug level). 相似文献