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1.
Erythropoietin(EPO) is one of the most successful biopharmaceuticals in history and is used for treating anemia of different origins. However, it became clear that EPO could also work in a neuroprotective, antiapoptotic, antioxidative, angiogenetic and neurotropic way. It causes stimulation of cells to delay cell apoptosis, especially in the central nervous system. In rodent models of focal cerebral ischemia, EPO showed an impressive reduction of infarct size by 30% and improvement of neurobehavioral outcome by nearly 40%. A large animal model dealing with ischemia and reperfusion of the spinal cord showed that EPO could reduce the risk of spinal cord injury significantly. In addition, some clinical studies tested whether EPO works in real live clinical settings. One of the most promising studies showed the innocuousness and improvements in follow-up, outcome scales and in infarct size, of EPO-use in humans suffering from ischemic stroke. Another study ended unfortunately in a negative outcome and an increased overall death rate in the EPO group. The most possible reason was the involvement of patients undergoing simultaneously systemic thrombolysis with recombinant tissue plasminogen activator. An experimental study on rats demonstrated that administration of EPO might exacerbate tissue plasminogen activator-induced brain hemorrhage without reducing the ischemic brain damage. This case shows clearly how useful animal models can be to check negative side effects of a treatment before going into clinical trials. Other groups looked in human trials at the effects of EPO on the outcome after ischemic stroke, relation to circulating endothelial progenitor cells, aneurysmal subarachnoid hemorrhage, traumatic brain injury, hemoglobin transfusion thresholds and elective first-time coronary artery bypass surgery. Most of the results were positive, but are based mostly on small group sizes. However, some of the most neglected facts when focusing on experimental setups of ischemia of the central nervous system are issues like age and comorbidities. It might be extremely worthy to consider these points for future projects, because EPO might influence all these factors.  相似文献   
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Background: Hypotension due to vasodilation during subarachnoid block (SAB) for elective cesarean delivery may be harmful. Heart rate variability (HRV), reflecting autonomic control, may identify patients at risk of hypotension.

Methods: Retrospectively, HRV was analyzed in 41 patients who were classified into one of three groups depending on the decrease in systolic blood pressure (SBP): mild (SBP > 100 mmHg), moderate (100 > SBP > 80 mmHg), or severe (SBP < 80 mmHg). Prospectively, HRV and hemodynamic data of 19 patients were studied. Relative low frequency (LF), relative high frequency (HF), and LF/HF ratio were analyzed.

Results: Retrospective analysis of HRV showed a significantly higher sympathetic and lower parasympathetic drive in the groups with moderate and severe compared with mild hypotension before SAB (median, 25th/75th percentiles): LF/HF: mild: 1.2 (0.9/1.8), moderate: 2.8 (1.8/4.6), P < 0.05 versus mild; severe: 2.7 (2.0/3.5), P < 0.05 versus mild. Results were confirmed by findings of LF and HF. Prospectively, patients were grouped according to LF/HF before SAB: low-LF/HF: 1.5 (1.1/2.0) versus high-LF/HF: 4.0 (2.8/4.7), P < 0.05; low-LF: 58 +/- 9% versus high-LF: 75 +/- 10%, P < 0.05; low-HF: 41 +/- 10% versus high-HF: 25 +/- 10%, P < 0.05. High-risk patients had a significantly lower SBP after SAB (76 +/- 21 vs. 111 +/- 12 mmHg; P < 0.05).  相似文献   

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Sepsis is a clinical syndrome that is usually induced by bacterial infections. It is generally assumed that the syndrome results from an excessive triggering of endogenous inflammatory mediators by the invading microorganisms. These mediators include substances released by activated monocytes, macrophages, endothelial cells and neutrophils such as cytokines, reactive oxygen species and proteases, as well as activation products of coagulation, fibrinolysis, contact and complement systems. Recent studies have suggested that cytokines and complement activation products may have overlapping biological activities. In addition, multiple interactions in vitro as well as in vivo between cytokines and complement have been described. Here we will review some of these recent studies and will discuss their relevance for the pathogenesis of sepsis and septic shock.  相似文献   
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Summary One of the most common side effects of treatment with recombinant interleukin-2 (IL-2) is capillary leakage. Its genesis is not completely understood. The aim of the study was to determine whether capillary leakage can be monitored by means of a non-invasive conductivity technique and to study its starting point. Eight patients with advanced renal cell cancer were studied in a medium care section of the Department of Medical Oncology, University Hospital over 4 days during treatment sessions of continuous, intravenously administered IL-2 (mean dose of 15.6 × 106 IU · m–2 · day –1). The fluid shift from the intravascular to the extra- and intracellular compartments was monitored by means of noninvasive conductivity measurements. Changes in blood volume were calculated from serial erythrocyte counts. The clinical parameters of capillary leakage (oliguria, positive fluid balance, and gain in mass) were recorded. The mean gain in mass was 9% after 4 days of IL-2 treatment. The extracellular fluid volume increased significantly [46 (SD 23.2)%; P < 0.01], whereas the intracellular fluid volume did not change. The increase in blood volume (BV) amounted to 7% (P < 0.05). The decline in albumin concentration was significantly more than the increase in BV [38 (SD 4.3) %; P < 0.01], indicating capillary albumin leakage. The main changes were observed after the 2nd day of treatment. From this study, it is suggested that conductivity measurements are a suitable method to monitor capillary leakage induced by IL-2, and could be used to detect the exact onset and severity of this leakage. The leakage started within the first 24 h of treatment and was detected as a fluid shift from the intravascular to the extracellular space, while the intracellular compartment remained stable. These measurements could be useful during intervention studies with the aim of preventing this adverse effect of IL-2.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Seit Mai 2020 können Hersteller einen Antrag zur Aufnahme einer digitalen Gesundheitsanwendung (DiGA) in das Verzeichnis...  相似文献   
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The number of patients returning to dialysis after graft failure increases. Surprisingly, little is known about the clinical and immunological outcomes of this cohort. We retrospectively analyzed 254 patients after kidney allograft loss between 1997 and 2017 and report clinical outcomes such as mortality, relisting, retransplantations, transplant nephrectomies, and immunization status. Of the 254 patients, 49% had died 5 years after graft loss, while 27% were relisted, 14% were on dialysis and not relisted, and only 11% were retransplanted 5 years after graft loss. In the complete observational period, 111/254 (43.7%) patients were relisted. Of these, 72.1% of patients were under 55 years of age at time of graft loss and only 13.5% of patients were ≥65 years. Age at graft loss was associated with relisting in a logistic regression analysis. In the complete observational period, 42 patients (16.5%) were retransplanted. Only 4 of those (9.5%) were ≥65 years at time of graft loss. Nephrectomy had no impact on survival, relisting, or development of dnDSA. Patients after allograft loss have a high overall mortality. Immunization contributes to long waiting times. Only a very limited number of patients are retransplanted especially when ≥65 years at time of graft loss.  相似文献   
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