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21.
To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA.  相似文献   
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Letermovir is a new antiviral drug approved for the prophylaxis of CMV infection in allogeneic stem cell transplants. The aim of the study was to assess the therapeutic efficacy of letermovir in difficult to treat CMV infections in lung transplant recipients. All lung transplant recipients between March 2018 and August 2020, who have been treated with letermovir for ganciclovir-resistant or refractory CMV infection were included in the study and analysed retrospectively. In total, 28 patients were identified. CMV disease was present in 15 patients (53.6%). In 23 patients (82.1%), rapid response was noticed, and CMV-viral load could be significantly decreased (>1 log10) after a median of 17 [14–27] days and cleared subsequently in all of these patients. Five patients (17.9%) were classified as non-responder. Thereof, development of a mutation of the CMV UL56 terminase (UL-56-Gen: C325Y) conferring letermovir resistance could be observed in three patients (60%). Common side effects were mild and mostly of gastrointestinal nature. Mild adjustments of the immunosuppressive drugs were mandatory upon treatment initiation with letermovir. In addition to other interventions, letermovir was effective in difficult to treat CMV infections in lung transplant recipients. However, in patients with treatment failure mutation conferring letermovir, resistance should be taken into account.  相似文献   
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PURPOSE: We tested the hypothesis that degranulation of granulocytes and upregulation of the granulocyte integrin MA-1 (CD11b/CD18) are related to exercise duration and/or intensity. We also investigated whether or not the expression of MAC-1 would be influenced by body temperature or dehydration. Moreover, we tested the hypothesis that changes in leukocyte counts and changes in MAC1 expression with endurance exercise are independently regulated. METHODS: In eight amateur runners, MAC-1 (CD11b/CD18) surface expression on granulocytes was determined by fluorescent antibody cell sorting, before and after an incremental maximal treadmill test, a moderate 3-h run, and a competitive marathon race. RESULTS: Expression CD11b on granulocytes was increased by 10+/-9.6% (P < 0.05) after the maximal treadmill test and by 84+/-76% (P < 0.01) after the marathon run. There was no change in CD11b expression after the moderate 3-h run. CD18 expression was not significantly changed after any of the exercise protocols. CONCLUSION: Expression of CD11b on granulocytes is increased with intense endurance exercise, either incremental maximal treadmill testing or competitive marathon running, but not in moderate endurance training. Thus, exhaustive exercise may be one mechanism for the upregulation of integrin adhesive receptors on granulocytes. This phenomenon could be in part responsible for increased adhesion of granulocytes to endothelial cells and could facilitate tissue infiltration after endurance exercise.  相似文献   
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This is a report of a study aimed at putting into practice a new theory for hypothermic preservation of viable organs. A perfusion fluid elaborated according to this theory was applied in preservation of the heart, and resulted in storage of the heart for up to 72 hours with preservation of its functions (rhythm, presystolic ventricular pressure, systolic ventricular pressure, cardiac work, coronary blood pressure, sensitivity to drugs) and its morphology. An important finding was that repeated heart storage for 24 hours alternating with functional testing for 5–7 hours could be performed without irreversible alterations of cardiac function and fine structure. Furthermore, during functional testing following storage the hearts consistently demonstrated improvement of function in time, suggesting that the preserved myocardial tissues were able to rapidly achieve metabolic reequilibration. The results of this study provide the possibility of developing a system for efficient ex vivo heart conditioning before transplantation.
Résumé Nous avons testé la valeur d'une nouvelle théorie sur la préservation d'organes en hypothermie. Un liquide de perfusion conforme à cette théorie a été utilisé pour la préservation cardiaque. Il permet de conserver le coeur pendant 72 heures, sans altérations de ses fonctions (rythme, pression ventriculaire pré-systolique et systolique, travail cardiaque, pression coronaire, sensibilité aux médicaments) ni de sa morphologie. De plus, le coeur peut-être, à plusieurs reprises, conservé pendant 24 heures, avec des intervalles de reprise fonctionnelle de 5–7 heures, sans que sa fonction ni sa structure fine ne soient altérées de façon irréversible. Enfin, l'étude fonctionnelle montre qu'après conservation la fonction cardiaque s'améliore avec le temps, suggérant donc une rééquilibration métabolique rapide du tissu myocardique. Les résultats de cette étude permettront la mise au point d'un système efficace de conservation cardiaque ex-vivo en vue de la transplantation.


Supported by the German Heart Center, Munich, and the German Academy Department for Foreign Scientific Relationships, Bonn.  相似文献   
30.
Qureshi AI  Luft AR  Sharma M  Guterman LR  Hopkins LN 《Neurosurgery》2000,46(6):1360-75; discussion 1375-6
We reviewed the incidence, risk factors, and clinical features of thromboembolic and ischemic events associated with diagnostic cerebral angiography, endovascular treatment of aneurysms using coils or balloons, angioplasty and stent placement to treat extracranial carotid artery stenosis, and embolization of arteriovenous malformations using glue or other embolic agents. We performed a cumulative analysis to determine the frequency and characteristics of these events and a subset analysis (whenever possible) to determine the benefits of various strategies for complication avoidance. Of the 1,547 patients who underwent Guglielmi detachable coil treatment, thromboembolic events were observed for 127 (8.2%), consisting of asymptomatic events for 12 patients, transient ischemic attacks for 29, and strokes for 86. The outcomes for the 86 patients with strokes were categorized as full recovery for 15, good recovery for 27, partial recovery for 19, no recovery for 11, death for 12, and undetermined outcome for 2. Of the 834 patients who underwent carotid angioplasty and stent placement, thromboembolic events were observed for 73 (8.8%), consisting of transient ischemic attacks for 26 patients and strokes for 47. The outcomes for the patients with strokes were categorized as full recovery for 20, good recovery for 15, partial recovery for 6, no recovery for 2, and death for 4. High rates of thromboembolic events were also observed with balloon occlusion of aneurysms (11%) or parent arteries (19%) and carotid angioplasty alone (5.9%). Arteriovenous malformation embolization was associated with an ischemic event/procedure rate of 9.4%. High rates of thromboembolic and ischemic complications, with subsequent morbidity and death, are associated with most endovascular procedures. Further research and the formulation of standard preventive guidelines may help to reduce these risks and improve the overall success of these procedures.  相似文献   
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