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121.

Introduction

Recombinant human activated protein C (rhAPC) is the first drug for which a reduction of mortality in severe sepsis has been demonstrated. However, the mechanism by which this reduction in mortality is achieved is still not clearly defined. The aim of the present study was to evaluate the dynamics of the anticoagulant, anti-inflammatory and pro-fibrinolytic action of rhAPC in patients with severe sepsis, by comparing rhAPC-treated patients with case controls.

Methods

In this prospectively designed multicenter case control study, 12 patients who were participating in the ENHANCE study, an open-label study of rhAPC in severe sepsis, were treated intravenously with rhAPC at a constant rate of 24 μg/kg/h for a total of 96 h. Twelve controls with severe sepsis matching the inclusion criteria received standard therapy. The treatment was started within 48 h after the onset of organ failure. Blood samples were taken before the start of the infusion and at 4, 8, 24, 48, 96 and 168 h, for determination of parameters of coagulation and inflammation.

Results

Sepsis-induced thrombin generation as measured by thrombin-antithrombin complexes and prothrombin fragment F1+2, was reset by rhAPC within the first 8 h of infusion. The administration of rhAPC did not influence parameters of fibrinolysis and inflammation. There was no difference in outcome or occurrence of serious adverse events between the treatment group and the control group.

Conclusion

Sepsis-induced thrombin generation in severely septic patients is reset by rhAPC within the first 8 h of infusion without influencing parameters of fibrinolysis and inflammation.  相似文献   
122.
目的:建立肠系膜微淋巴管内皮细胞的培养技术,观察不同体积分数的休克淋巴液对大鼠肠系膜微淋巴管内皮细胞形态的影响。方法:实验于2004-02/07在河北北方学院病理生理学教研室及实验中心细胞培养室完成。选择健康雄性Wistar大鼠,体质量分别为220~300g和50~80g。实验方法:①无菌条件下制备大鼠重症失血性休克模型,引流肠系膜淋巴液或收集门静脉血;同时另取大鼠,引流正常淋巴液或正常门静脉血。②从动物种类、培养基、植块方法、胎牛血清浓度等方面对植块培养法进行改良,进行肠系膜微淋巴管内皮细胞原代培养并传代。实验分组:分为6组:胎牛血清组:培养液为DMEM 体积分数为0.1的胎牛血清;正常淋巴液组:培养液为DMEM 正常淋巴液;休克淋巴液组:培养液为DMEM 体积分数为0.04,0.06,0.08,0.10的休克淋巴液;正常血浆组:培养液为DMEM 正常血浆;休克血浆组:培养液为DMEM 休克血浆;无血清对照组:培养液为DMEM。实验评估:①光镜下观察大鼠肠系膜微淋巴管内皮细胞原代培养及传代情况。②光镜、扫描电镜及透射电镜下观察不同体积分数的休克淋巴液及不同作用时间(4,8,12h)对肠系膜微淋巴管内皮细胞形态及超微结构的影响。结果:①光镜下肠系膜微淋巴管内皮细胞原代培养及传代情况:内皮细胞呈扁平的梭形或多边形,大小均匀,胞核清晰,呈卵圆形。细胞生长融合形成单层后,呈典型的鹅卵石或铺路石样镶嵌状排列生长。②光镜下在休克淋巴液中肠系膜微淋巴管内皮细胞形态:体积分数为0.04的休克淋巴液作用4h时细胞逐渐收缩、变圆直至脱落漂浮,随着休克淋巴液体积分数增加及作用时间延长,细胞损伤逐渐加重,体积分数为0.08的休克淋巴液作用4h时核旁出现空泡,体积分数为0.10的休克淋巴液作用12h时细胞裂解成碎片。其他各组作用12h肠系膜微淋巴管内皮细胞形态无显著改变。③扫描电镜下在休克淋巴液中肠系膜微淋巴管内皮细胞形态:体积分数为0.04的休克淋巴液作用4h部分细胞逐渐收缩离壁,细胞间隙增大、细胞边缘的突起拉长、缩短、断裂,作用8,12h可见凋亡小体。其他各组作用12h肠系膜微淋巴管内皮细胞形态无显著改变。④透射电镜下在休克淋巴液中肠系膜微淋巴管内皮细胞形态:体积分数为0.04的休克淋巴液作用4h细胞膜形态不规整,胞浆内质网等膜性细胞器扩张,核形态不规则,作用8h线粒体呈球形扩张,细胞核逐渐出现固缩、似细胞凋亡改变,核周腔变宽;体积分数为0.08的休克淋巴液作用时间8h细胞内出现囊泡,内质网不同程度扩张,线粒体主要表现为浓缩、深染等改变,细胞膜边界不清,出现起泡、破碎等现象。其他各组作用12h肠系膜微淋巴管内皮细胞形态无显著改变。结论:成功建立了肠系膜微淋巴管内皮细胞的培养技术;休克淋巴液可导致肠系膜微淋巴管内皮细胞形态及超微结构损伤。  相似文献   
123.
To study red cell transfusion practice in 3216 coronary artery bypass graft (CABG) cases in 11 hospitals in 1988, abstracted patient records were stratified by diagnosis related group (DRG) (that is, DRG 106, coronary artery bypass without catheterization, or DRG 107, coronary artery bypass with catheterization) and International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) surgical procedure code. Means of units per transfused patient, age and length of stay, and in-hospital mortality rates were significantly greater for patients in DRG 106 than DRG 107. Gender was a significant factor for transfusion outcomes; female patients were more likely to undergo transfusion, and, when transfused, they received more units of red cells than male patients. For a given DRG/ICD-9-CM surgical procedure class, significant differences were found between hospitals in the percentage of patients transfused, but not in mean units of red cells per transfused patient. However, within individual hospitals, the proportion of patients transfused and the number of units per transfused patient did not vary significantly across DRG/ICD-9-CM procedure classes. These results suggest that circumstances operating within a hospital, still to be identified, had more influence on transfusion decisions than the nature of the surgical intervention.  相似文献   
124.
Preclinical studies of recombinant human interleukin-3 (rhIL-3) and granulocyte-macrophage colony-stimulating factor (rhGM-CSF) have shown enhancement of multilineage hematopoiesis when administered sequentially. This study was designed to evaluate the safety, tolerability, and biologic effects of sequential administration of rhIL- 3 and rhGM-CSF after marrow ablative cytotoxic therapy and autologous bone marrow transplantation (ABMT) for patients with malignant lymphoma. Thirty-seven patients (20 patients with non-Hodgkin's lymphoma and 17 patients with Hodgkin's disease) received one of four different treatment regimens before ABMT. Patients were entered in one of four study groups to receive rhIL-3 (2.5 or 5.0 micrograms/kg/day) administered by subcutaneous injection for either 5 or 10 days starting 4 hours after the marrow infusion. Twenty-four hours after the last dose of rhIL-3, rhGM-CSF (250 micrograms/m2/d as a 2-hour intravenous infusion) administration was initiated. rhGM-CSF was administered daily until the absolute neutrophil count (ANC) was > or = 1,500/microL for 3 consecutive days or until day 27 posttransplant. The most frequent adverse events in the trial included nausea, fever, diarrhea, mucositis, vomiting, rash, edema, chills, abdominal pain, and tachycardia. Three patients were removed from the study because of chest, skeletal, and abdominal pain felt to be probably related to study drug. Four patients died during the study period because of complications unrelated to either rhIL-3 or rhGM-CSF. The median time to recovery of neutrophils (ANC > or = 500/microL) and platelets (platelet count > or = 20,000/microL) was 14 and 15 days, respectively. There were fewer days of platelet transfusions than seen in historical control groups using rhGM-CSF, rhG-CSF, or rhIL-3 alone. In addition, there were fewer days of red blood cell transfusions compared with historical controls using no cytokines or rhGM-CSF. These data indicate that the sequential administration of rhIL-3 and rhGM-CSF after ABMT is safe and generally well-tolerated and results in rapid recovery of multilineage hematopoiesis.  相似文献   
125.
Menitove  JE; Pereira  J; Hoffman  R; Anderson  T; Fried  W; Aster  RH 《Blood》1989,73(6):1561-1569
Serial studies were performed in two patients with cyclic thrombocytopenia to investigate the pathogenesis of this disorder. Mean life span of autologous platelets when platelet levels were declining was subnormal (2.4 and 0.8 days), and megakaryocytes were abundant in the bone marrow during thrombocytopenia. Megakaryocyte colony- stimulating activity could not be detected in the serum of either patient at any point of their cycles. In each patient, total platelet- associated IgG varied inversely with platelet levels. Surface platelet- associated IgG was measured only in patient 2 and was significantly elevated (greater than 1,280 IgG molecules per platelet) at all stages of the cycle, even during thrombocytosis. However, the highest values were observed during thrombocytopenia. Platelet-bindable IgG in plasma declined to normal immediately before platelet levels began to rise. IgG eluted from the platelets of this patient reacted strongly with autologous and homologous platelets in contrast to a "mock eluate" prepared from platelets of a normal subject. The eluate from the patient's platelets reacted strongly with immobilized autologous and homologous glycoprotein IIb/IIIa complex and weakly with GPIb but not with isolated GPIIIa alone. In each patient the decline in platelet levels was significantly delayed following administration of intravenous gamma globulin 0.4 g/kg body weight for five days. These findings suggest that platelet-reactive autoantibodies are of pathogenic significance in some patients with cyclic thrombocytopenia.  相似文献   
126.
We examined 26 patients with human immunodeficiency virus-1 (HIV-1)- associated Kaposi's sarcoma (KS), and 76 HIV-1-infected (HIV-1+) people without KS or uninfected (HIV-1-) controls for the presence of circulating KS-like spindle cells. Adherent cells that had spindle morphology and several characteristics of spindle cells of KS lesions (KS cells) were identified in the peripheral blood mononuclear cell fraction only after culture in the presence of conditioned medium (CM) from activated lymphocytes. The peripheral blood-derived spindle cells (PBsc) expressed a variety of endothelial cell markers, such as Ulex europaeus I lectin, EN4, EN2/3, EN7/44, CD13, CD34, CD36, CD54, ELAM-1, and HLA-DR. However, they were negative for CD2, CD19, PaIE, and factor VIII-related antigen. The PBsc produced angiogenic factors as evidenced by the ability of CM from these cells to promote growth of normal vascular endothelial cells. In addition, subcutaneously injected PBsc stimulated angiogenesis in vivo in athymic nude mice. We determined that the number of PBsc grown from the peripheral blood of HIV-1+ patients with KS or at high risk to develop KS were increased by 78- fold (P = .0001) and 18-fold (P = .005), respectively, when compared with HIV-1- controls. The number of spindle cells cultured from the HIV- 1+ patients at low risk for developing KS, eg, HIV-1+ injection drug users, showed no statistical increase when compared with HIV-1- controls. The presence of increased PBsc with characteristics of KS cells in HIV-1+ KS patients or patients at high risk for developing KS gives insights into the origin of KS cells and may explain the multifocal nature of the disease. In addition, this may be useful in predicting the risk of KS development.  相似文献   
127.
128.
We performed a detailed kinetic study on the in vivo effect of a single subcutaneous dose of granulocyte colony-stimulating factor (G-CSF; 300 micrograms) in four healthy individuals on the expression and function of neutrophil Fc gamma receptors (Fc gamma R). G-CSF did not induce Fc gamma RI (CD64) on circulating neutrophils. However, neutrophils newly formed in response to G-CSF were Fc gamma RI positive and were able to perform antibody-dependent cellular cytotoxicity in an Fc gamma RI- dependent way. Fc gamma RII (CD32) expression was not changed significantly. Fc gamma RIII (CD16, phosphatidylinositol-linked) expression, slightly increased immediately (30 minutes) postinjection, was found to be strongly decreased on the newly formed population. For comparison, we studied the expression of the PI-linked proteins leukocyte alkaline phosphatase (LAP) and CD14. Intracellular levels of LAP mirrored the biphasic expression pattern as membrane-bound Fc gamma RIII. In contrast, CD14 expression on neutrophils was initially constant, followed by high levels on the newly formed neutrophils. Soluble CD14 levels were found to be elevated transiently, whereas peak levels of soluble Fc gamma III were observed as late as 6 days postinjection. In conclusion, we have shown that G-CSF results in an immunophenotypically and functionally altered neutrophil population for an important part as a result of its effect on myeloid precursor cells.  相似文献   
129.
Singer  RH; Byron  KS; Lawrence  JB; Sullivan  JL 《Blood》1989,74(6):2295-2301
We have demonstrated that a sensitive, nonisotopic in situ hybridization (ISH) assay can be used to detect HIV-infected cells from seropositive, asymptomatic individuals. Our assay is based on the detection of a biotinated HIV DNA probe hybridized to human immunodeficiency virus (HIV)-infected peripheral blood lymphocytes (PBL) using streptavidin and alkaline phosphatase to identify positive cells. This assay is rapid in that it can be performed within a day and is sensitive enough to unambiguously identify a rare, single, positive cell. Patient samples derived from HIV-seropositive hemophiliacs and HIV-seropositive infants were analyzed before and after coculture with normal PBL. The same samples were investigated using a Dupont P24 antigen-capture kit. It was found that ISH always detected the same positive samples as antigen capture, often in shorter times of coculture. In situ hybridization detected over half of our HIV-infected hemophilia patient population as virus positive, whereas the antigen capture assay detected less than one fourth as virus positive. In situ hybridization detected positive cells directly, without coculture, in 12 out of 35 (34%) hemophiliacs and in three out of eight (37%) infants. The speed, sensitivity, and confidence of ISH and nonisotopic detection indicates that it will be useful as a tool for clinical research and diagnosis.  相似文献   
130.
Administration of recombinant human interleukin-7 (rhIL-7) to mice increases the exportation of myeloid progenitors (colony-forming unit [CFU]-c and CFU-granulocyte erythroid megakaryocyte macrophage [CFU- GEMM]) from the bone marrow (BM) to peripheral organs, including blood, and also increases the number of primitive progenitor and stem cells in the peripheral blood (PB). We now report that combined treatment of mice with rhIL-7 and recombinant human granulocyte-colony stimulating factor (rhG-CSF) stimulates a twofold to 10-fold increase in the total number of PB CFU-c, and a twofold to fivefold increase in the total number of PB CFU-spleen at day 8 (CFU-S8) over the increase stimulated by rhIL-7 or rhG-CSF alone. In addition, the quality of mobilized cells with trilineage, long-term marrow-repopulating activity is maintained or increased in mice treated with rhIL-7 and rhG-CSF compared with rhIL- 7 or rhG-CSF alone. These differences in mobilizing efficiency suggest qualitative differences in the mechanisms by which rhIL-7 and rhG-CSF mobilize progenitor cells, in fact, the functional status of progenitor cells mobilized by rhIL-7 differs from that of cells mobilized by rhG- CSF in that the incidence of actively cycling (S-phase) progenitors obtained from the PB is about 20-fold higher for rhIL-7-treated mice than for mice treated with rhG-CSF. These results suggest the use of rhIL-7-mobilized progenitor/stem cells for gene-modification and tracking studies, and highlight different functions and rates of repopulation after reconstitution with PB leukocytes obtained from mice treated with rhIL-7 versus rhG-CSF.  相似文献   
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