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Acute kidney injury (AKI) is a frequently occurring complication in ICU patients and is associated with decreased short- and long-term survival. Gammelager and colleagues showed that AKI patients are at increased risk for developing heart failure and myocardial infarction at long-term follow-up. Their study provides strong epidemiological data on cardiorenal syndrome type 3, and their findings help explain the worse long-term survival of AKI patients. Finally, it also highlights the need for specific follow-up programs for ICU survivors.In a recent article, Gammelager and colleagues [1] investigated the association between acute kidney injury (AKI) and long-term cardiac morbidity and stroke in a representative ICU cohort. AKI occurs in one- to two-thirds of ICU patients and is associated with worse outcome [2,3]. Short-term worse outcomes can be explained by the effects of decreased kidney function, such as volume overload and retention of uremic toxins [4]. Long-term outcomes are probably affected by development of chronic kidney disease [5]. Recently, there has been increased interest in the complex interaction between the kidney and heart. AKI leading to acute cardiac events has been termed cardiorenal syndrome type 3 (CRS-3) [6]. At present this concept is only sparsely supported by human data [7]. The study by Gammelager and colleagues is one of the first providing high-quality data on CRS-3 in ICU patients.Several groups, including the group of Gammelager and colleagues, have demonstrated worse long-term outcomes for AKI patients [3,8-11]. The present study by Gammelager and colleagues demonstrates that cardiovascular disease may contribute to these worse outcomes. Over a 3-year period, AKI stage 1 and greater was associated with heart failure (hazard ratio 1.33), and AKI stages 2 and 3 were associated with myocardial infarction (hazard ratio 1.51). Similar findings were reported before by James and colleagues [12] in a cohort of non-ICU patients after coronary angiography. The paper by Gammelager and colleagues is one of the first providing long-term epidemiologic data on CRS-3 in ICU patients. Importantly, it shows that CRS-3 is also relevant for patients discharged from the ICU, a less well-recognized aspect of CRS-3.These findings are strengthened by the methodological quality of the study. Selection bias was limited by including a large multicenter ICU cohort, and a population-based medical registry guaranteed virtually complete patient follow-up. Studies using different AKI definitions cannot be compared. Therefore, it is crucial that the universally accepted KDIGO (Kidney Disease: Improving Global Outcomes) definition for AKI was used [13].A limitation is that administrative data were used for recoding of the endpoints. Administrative databases may be limited by both over- and under-reporting, and also miss detailed information on, for example, severity of heart failure. Also, an epidemiologic study can only demonstrate an association, rather than prove a causal effect, in this case between AKI and cardiac events. These data on CRS-3 are therefore hypothesis generating and should prompt further research on the pathophysiologic mechanisms explaining the worse cardiovascular outcomes.How can we explain this increased risk for cardiovascular events? This may be mediated, especially in the long-term, by chronic kidney disease developing after AKI, but other factors may also play a role [5]. In the acute phase, AKI may exert a negative impact on the heart, leading to cellular response with apoptosis, remodeling and fibrosis, which may ultimately lead to arrhythmias, conduction abnormalities, heart failure, and ischemia [7,14].The study by Gammelager and colleagues is also one of the few that reports on the association between AKI and stroke, but showed no association during the 3-year follow-up. These findings are in contrast to those found in Taiwan by Wu and colleagues [15], where in a matched case-controlled study AKI patients had a higher risk and higher severity of stroke than non-AKI patients. An important difference with the cohort of Gammelager and colleagues was that the study cohort included only severe AKI treated with renal replacement therapy and was not limited to ICU patients. Severity of AKI may therefore play a role in risk for stroke.Another important lesson that can be learned from these long-term outcome data is that AKI survivors should have long-term follow-up. We were already aware that follow-up of kidney function is important, but these data also highlight the importance of cardiovascular follow-up. As other types of ICU survivors also have specific long-term morbidity issues, this highlights the need for specific and multidisciplinary follow-up programs for ICU survivors.  相似文献   
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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   
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BACKGROUND & AIMS: Intestinal transplantation is a developing therapeutic option for patients with irreversible intestinal failure or short bowel syndrome. The aim of this study was to delineate the histopathology of human intestinal allografts and to define the features of intestinal rejection. METHODS: The histological features of 3015 endoscopic biopsy specimens and 23 allograft specimens from 62 intestinal recipients were analyzed retrospectively and correlated with clinical findings. RESULTS: Acute allograft rejection was characterized by a varying combination of crypt injury, mucosal infiltration primarily by mononuclear cells (including blastic lymphocytes), and increased crypt cell apoptosis (more than 2 per 10 crypts). It represented a patchy, often ileal-centered process that could progress to mucosal ulceration; later episodes (more than 100 days posttransplant) tended to show lesser cellular infiltration and greater apoptosis than earlier episodes. Correlation with clinical rejection was good (false-positive rate of 9%; false-negative rate of 26%). Two resected specimens showed obliterative arteriopathy indicative of chronic rejection. In other specimens, preservation injury, cytomegalovirus infection, post-transplant lymphoproliferative disorder, and nonspecific features of active or past mucosal injury could be recognized. CONCLUSIONS: Mucosal biopsy specimens are a useful means of monitoring intestinal allografts. Based on features validated by clinical correlation, acute rejection can be identified reliably and can be differentiated from the other pathological processes affecting the intestinal allograft. (Gastroenterology 1996 Jun;110(6):1820-34)  相似文献   
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Nielsen  OJ; Schuster  SJ; Kaufman  R; Erslev  AJ; Caro  J 《Blood》1987,70(6):1904-1909
Production of immuno and biologically active erythropoietin was documented to occur in the human hepatoblastoma cell line HepG-2. The expression of the erythropoietin gene was further verified by Northern blot analysis using a single stranded RNA probe. In vitro studies showed that erythropoietin production by these cells was not stimulated by hypoxia or cobalt chloride, but was related to the proliferative activity of the cells in culture. In addition it was found that the secretion of erythropoietin was almost completely abrogated by tunicamycin, an inhibitor of N-linked glycosylation. This effect of tunicamycin was also observed in a permanently transfected cell line that secretes erythropoietin in large quantities.  相似文献   
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Background

A major change has occurred in the last few years in the therapeutic approach to patients presenting with all forms of acute coronary syndromes. Whether or not these patients present initially to tertiary cardiac care centers, they are now routinely referred for early coronary angiography and increasingly undergo percutaneous revascularization. This practice is driven primarily by the angiographic image and technical feasibility. Concomitantly, there has been a decline in expectant or ischemia-guided medical management based on specific clinical presentation, response to initial treatment, and results of noninvasive stratification. This 'tertiarization' of acute coronary care has been fuelled by the increasing sophistication of the cardiac armamentarium, the peer-reviewed publication of clinical studies purporting to show the superiority of invasive cardiac interventions, and predominantly supporting (non-peer-reviewed) editorials, newsletters, and opinion pieces.

Discussion

This review presents another perspective, based on a critical reexamination of the evidence. The topics addressed are: reperfusion treatment of ST-elevation myocardial infarction; the indications for invasive intervention following thrombolysis; the role of invasive management in non-ST-elevation myocardial infarction and unstable angina; and cost-effectiveness and real world considerations. A few cases encountered in recent practice in community and tertiary hospitals are presented for illustrative purposes The numerous and far-reaching scientific, economic, and philosophical implications that are a consequence of this marked change in clinical practice as well as healthcare, decisional and conflict of interest issues are explored.

Summary

The weight of evidence does not support the contemporary unfocused broad use of invasive interventional procedures across the spectrum of acute coronary clinical presentations. Excessive and unselective recourse to these procedures has deleterious implications for the organization of cardiac health care and undesirable economic, scientific and intellectual consequences. It is suggested that there is need for a new equilibrium based on more refined clinical risk stratification in the treatment of patients who present with acute coronary syndromes.  相似文献   
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