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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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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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pp32r1 (ANP32C) is oncogenic and has been shown to be overexpressed in tumors of the breast, prostate, and pancreas. In this work we show that pp32 family proteins are able to bind to the sphingosine analog FTY720 (Finguimod). Molecular docking studies highlight that a conserved residue F136 is likely to be a key determinant of the FTY720 binding site on the pp32 leucine-rich repeat domain. Transduction of the renal carcinoma cell line ACHN or cervical cancer cell line HeLa with lentivirus expressing the oncogenic family member pp32r1 or a pp32r1Y140H functional mutant illustrated an enhanced resistance to FTY720 induced apoptosis. These findings highlight that certain cancers overexpressing pp32r1 or pp32r1 mutants are likely to demonstrate enhanced resistance to FTY720 treatment.  相似文献   
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Calcifying echinoid larvae respond to changes in seawater carbonate chemistry with reduced growth and developmental delay. To date, no information exists on how ocean acidification acts on pH homeostasis in echinoderm larvae. Understanding acid–base regulatory capacities is important because intracellular formation and maintenance of the calcium carbonate skeleton is dependent on pH homeostasis. Using H+-selective microelectrodes and the pH-sensitive fluorescent dye BCECF, we conducted in vivo measurements of extracellular and intracellular pH (pHe and pHi) in echinoderm larvae. We exposed pluteus larvae to a range of seawater CO2 conditions and demonstrated that the extracellular compartment surrounding the calcifying primary mesenchyme cells (PMCs) conforms to the surrounding seawater with respect to pH during exposure to elevated seawater pCO2. Using FITC dextran conjugates, we demonstrate that sea urchin larvae have a leaky integument. PMCs and spicules are therefore directly exposed to strong changes in pHe whenever seawater pH changes. However, measurements of pHi demonstrated that PMCs are able to fully compensate an induced intracellular acidosis. This was highly dependent on Na+ and HCO3, suggesting a bicarbonate buffer mechanism involving secondary active Na+-dependent membrane transport proteins. We suggest that, under ocean acidification, maintained pHi enables calcification to proceed despite decreased pHe. However, this probably causes enhanced costs. Increased costs for calcification or cellular homeostasis can be one of the main factors leading to modifications in energy partitioning, which then impacts growth and, ultimately, results in increased mortality of echinoid larvae during the pelagic life stage.  相似文献   
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OBJECTIVE--To determine the ability of conventional and Doppler echocardiography to distinguish between minor, acute massive, and subacute massive pulmonary embolism in patients with confirmed pulmonary embolism. DESIGN--Prospective study of a consecutive series of 47 patients with confirmed pulmonary embolism. SETTING--Department of internal medicine, university clinic. PATIENTS--11 patients (23%) had minor, 23 patients (49%) had acute massive, and 13 patients (28%) had subacute massive pulmonary embolism. RESULTS--Dilatation of the right ventricular cavity (33 (92%)) and asynergy of the right ventricular free wall (29 (81%)) were seen only in patients with acute and subacute massive pulmonary embolism (n = 36). 23 (64%) with pulmonary hypertension had tricuspid regurgitation. The velocity of the tricuspid regurgitant jet correlated with the pulmonary arterial pressure (r = 0.88, SEE = 11.6 mm Hg) and was significantly lower in patients with acute massive pulmonary embolism (3.0 (0.4) m/s, n = 12) than in patients with subacute massive pulmonary embolism (4.2 (0.6) m/s; n = 11) (p < 0.001). The use of predefined indices (right ventricular free wall thickness > 5 mm; tricuspid regurgitant jet velocity > 3.7 m/s; and the occurrence of both a dilated right ventricular cavity with normal interventricular septal motion, or an inspiratory collapse of the inferior vena cava, or both) correctly identified 11 of 13 patients (85%) with subacute massive pulmonary embolism. CONCLUSION--Conventional and Doppler echocardiography were successful in evaluating the haemodynamic consequences of pulmonary embolism.  相似文献   
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