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41.
Anemia and blood transfusion in critically ill patients   总被引:31,自引:1,他引:31  
Context  Anemia is a common problem in critically ill patients admitted to intensive care units (ICUs), but the consequences of anemia on morbidity and mortality in the critically ill is poorly defined. Objectives  To prospectively define the incidence of anemia and use of red blood cell (RBC) transfusions in critically ill patients and to explore the potential benefits and risks associated with transfusion in the ICU. Design  Prospective observational study conducted November 1999, with 2 components: a blood sampling study and an anemia and blood transfusion study. Setting and Patients  The blood sampling study included 1136 patients from 145 western European ICUs, and the anemia and blood transfusion study included 3534 patients from 146 western European ICUs. Patients were followed up for 28 days or until hospital discharge, interinstitutional transfer, or death. Main Outcome Measures  Frequency of blood drawing and associated volume of blood drawn, collected over a 24-hour period; hemoglobin levels, transfusion rate, organ dysfunction (assessed using the Sequential Organ Failure Assessment score), and mortality, collected throughout a 2-week period. Results  The mean (SD) volume per blood draw was 10.3 (6.6) mL, with an average total volume of 41.1 (39.7) mL during the 24-hour period. There was a positive correlation between organ dysfunction and the number of blood draws (r = 0.34; P<.001) and total volume drawn (r = 0.28; P<.001). The mean hemoglobin concentration at ICU admission was 11.3 (2.3) g/dL, with 29% (963/3295) having a concentration of less than 10 g/dL. The transfusion rate during the ICU period was 37.0% (1307/3534). Older patients and those with a longer ICU length of stay were more commonly transfused. Both ICU and overall mortality rates were significantly higher in patients who had vs had not received a transfusion (ICU rates: 18.5% vs 10.1%, respectively; 2 = 50.1; P<.001; overall rates: 29.0% vs 14.9%, respectively; 2 = 88.1; P<.001). For similar degrees of organ dysfunction, patients who had a transfusion had a higher mortality rate. For matched patients in the propensity analysis, the 28-day mortality was 22.7% among patients with transfusions and 17.1% among those without (P = .02); the Kaplan-Meier log-rank test confirmed this difference. Conclusions  This multicenter observational study reveals the common occurrence of anemia and the large use of blood transfusion in critically ill patients. Additionally, this epidemiologic study provides evidence of an association between transfusions and diminished organ function as well as between transfusions and mortality.   相似文献   
42.
Selective targeted delivery of TNFalpha to tumor blood vessels   总被引:4,自引:0,他引:4       下载免费PDF全文
We sought to enhance the selective toxicity of tumor necrosis factor alpha (TNFalpha) to permit its systemic use in cancer therapy. Because ligand-targeted therapeutics have proven successful in improving the selective toxicity of drugs, we prepared a fusion protein (L19mTNFalpha) composed of mouse TNFalpha and a high-affinity antibody fragment (L19 scFv) to the extradomain B (ED-B) domain of fibronectin, a marker of angiogenesis. L19mTNFalpha was expressed in mammalian cells, purified, and characterized. L19mTNFalpha was an immunoreactive and biologically active homotrimer. Radiolabeled L19mTNFalpha selectively targeted tumor neovasculature in tumor-bearing mice, where it accumulated selectively and persistently (tumor-to-blood ratio of the percentage of injected dose per gram [%ID/g] of 700, 48 hours from injection). L19mTNFalpha showed a greater anticancer therapeutic activity than both mTNFalpha and TN11mTNFalpha, a control fusion protein in which an antibody fragment, irrelevant in the tumor model used, substituted for L19. This activity was further dramatically enhanced by its combination with melphalan or the recently reported fusion protein L19-IL2. In conclusion, L19mTNFalpha allows concentrating therapeutically active doses of TNFalpha at the tumor level, thus opening new possibilities for the systemic use of TNFalpha in cancer therapy.  相似文献   
43.
Assessment and monitoring of hemodynamics is a cornerstone in critically ill patients as hemodynamic alteration may become life-threatening in a few minutes. Defining normal values in critically ill patients is not easy, because 'normality' is usually referred to healthy subjects at rest. Defining 'adequate' hemodynamics is easier, which embeds whatever pressure and flow set is sufficient to maintain the aerobic metabolism. We will refer to the unifying hypothesis proposed by Schrier several years ago. Accordingly, the alteration of three independent variables - heart (contractility and rate), vascular tone and intravascular volume - may lead to underfilling of the arterial tree, associated with reduced (as during myocardial infarction or hemorrhage) or expanded (sepsis or cirrhosis) plasma volume. The underfilling is sensed by the arterial baroreceptors, which activate primarily the sympathetic nervous system and renin-angiotensin-aldosterone system, as well as vasopressin, to restore the arterial filling by increasing the vascular tone and retaining sodium and water. Under 'normal' conditions, therefore, the homeostatic system is not activated and water/sodium excretion, heart rate and oxygen extraction are in the range found in normal subjects. When arterial underfilling occurs, the mechanisms are activated (sodium and water retention) - associated with low central venous oxygen saturation (ScvO2) if underfilling is caused by low flow/hypovolemia, or with normal/high ScvO2 if associated with high flow/hypervolemia. Although the correction of hemodynamics should be towards the correction of the independent determinants, the usual therapy performed is volume infusion. An accepted target is ScvO2 >70%, although this ignores the arterial underfilling associated with volume expansion/high flow. For large-volume resuscitation the worst solution is normal saline solution (chloride load, strong ion difference = 0, acidosis). To avoid changes in acid-base equilibrium the strong ion difference of the infused solution should be equal to the baseline bicarbonate concentration.  相似文献   
44.
Summary A combination of mitomycin C, vindesine and melphalan was administered to 33 patients with heavily pretreated refractory breast cancer. The overall response rate was 27% with a mean duration of more than 10.2 months. A stabilization with a mean duration of 5.1 months was seen in 56% of cases, while 20% of patients progressed. Gastrointestinal toxicity, mostly grade 1 or 2 nausea/vomiting was seen in 85% of cases, grade 1 or 2 leukopenia in 60% of patients, and grade 1 or 2 thrombocytopenia in 42%. Considering the good compliance of this regimen and the poor prognosis of patients with refractory advanced breast cancer, this combination can be useful as a palliative treatment of breast carcinoma.Abbreviations MMC mitomycin C - VDS vindesine - L-PAM melphalan  相似文献   
45.
46.
Background The histopathological characteristics of Chagas disease (ChD) are: presence of myocarditis, destruction of heart fibers, and myocardial fibrosis. Galectin-3 (Gal-3) is a biomarker involved in the mechanism of fibrosis and inflammation that may be useful for risk stratification of individuals with ChD.Objectives We sought to evaluate whether high Gal-3 levels are associated with severe forms of Chagas cardiomyopathy (CC) and whether they are predictive of mortality.Methods We studied anti-T. cruzi positive blood donors (BD): Non-CC-BD (187 BD without CC with normal electrocardiogram [ECG] and left ventricular ejection fraction [LVEF]); CC-Non-Dys-BD (46 BD with CC with abnormal ECG but normal LVEF); and 153 matched serum-negative controls. This cohort was composed of 97 patients with severe CC (CC-Dys). We used Kruskall-Wallis and Spearman’s correlation to test hypothesis of associations, assuming a two-tailed p<0.05 as significant.Results The Gal-3 level was 12.3 ng/mL for Non-CC-BD, 12.0 ng/mL for CC-Non-Dys-BD, 13.8 ng/mL for controls, and 15.4 ng/mL for CC-Dys. LVEF<50 was associated with higher Gal-3 levels (p=0.0001). In our linear regression adjusted model, we found association between Gal-3 levels and echocardiogram parameters in T. cruzi-seropositive subjects. In CC-Dys patients, we found a significant association of higher Gal-3 levels (≥15.3 ng/mL) and subsequent death or heart transplantation in a 5-year follow-up (Hazard ratio – HR 3.11; 95%CI 1.21–8.04; p=0.019).Conclusions In ChD patients, higher Gal-3 levels were significantly associated with severe forms of the disease and more long-term mortality, which means it may be a useful means to identify high-risk patients. (Arq Bras Cardiol. 2021; 116(2):248-256)  相似文献   
47.

Objectives

In numerous malignancies, angiogenin (ANG) and Maspin are important proangiogenic and antiangiogenic regulators, respectively. The aim of this study was to identify potential relationships between the biological roles of these two proteins in laryngeal squamous cell carcinoma (LSCC).

Methods

Immunohistochemical staining for ANG and Maspin was performed on specimens from 76 consecutive LSCC patients treated with surgery alone, considering the subcellular pattern of Maspin expression. Univariate and multivariate statistical models were used for prognostic purposes.

Results

On univariate analysis, a different level of ANG expression was seen for patients stratified by subcellular Maspin expression pattern: the mean ANG expression was higher in cases with a nonnuclear MASPIN expression than in those with a nuclear pattern (P=0.002). Disease-free survival (DFS; in months) differed significantly when patients were stratified by N stage (P=0.01). Patients whose Maspin expression was nonnuclear (i.e., it was cytoplasmic or there was none) had a significantly higher recurrence rate (P<0.001), and shorter DFS (P=0.01) than those with a nuclear Maspin pattern. The mean ANG expression was significantly higher in cases with loco-regional recurrent disease (P=0.007); and patients with an ANG expression ≥5.0% had a significantly shorter DFS than those with an ANG expression <5.0% (P=0.007). On multivariate analysis, ANG expression ≥5.0% was a significant, independent, negative prognostic factor in terms of DFS (P=0.041).

Conclusion

Our results support the hypothesis that a higher ANG expression is associated with a nonnuclear Maspin expression pattern in patients with LSCC. Further studies are needed to clarify the relationship between the ANG and Maspin pathways, and their potential diagnostic and therapeutic role in LSCC.  相似文献   
48.
Introduction: The anti-CD20 chimeric monoclonal antibody rituximab has revolutionized the treatment of B-cell malignancies, significantly improving patient clinical outcome. Recently, some single-group studies have suggested that adding rituximab to chemotherapy can improve the outcome of CD20-positive B-cell acute lymphoblastic leukemia (ALL) patients.

Areas covered: An overview of the current insights of rituximab in adult ALL patients is presented here. In particular, we focused on results of multicenter randomized phase III trial (GRAALL-2005 – Group for Research on Adult Acute Lymphoblastic Leukemia) that evaluated the benefit of associating rituximab to chemotherapy in Ph-negative, B-lineage ALL expressing the CD20 antigen.

Expert opinion: Data from clinical trials confirm that rituximab enhances the efficacy of chemotherapy without additive toxicity in ALL. However, results of GRAAL 2005 study represent only a modest incremental improvement in the treatment of ALL. Other promising compounds as single agent or in combination with chemotherapy are currently in different stages of clinical development. The GRAALL 2005 study sets the stage for other prospective studies which will further elucidate the role of monoclonal antibodies in the management of ALL.  相似文献   

49.
This aim of this study was assess whether positive and negative spiritual/religious coping (SRC) strategies are associated with depressive symptoms (DS) of informal caregiver (IC) of hospitalized older adults. A cross-sectional study was conducted among 98 IC of hospitalized older adults in the medical clinic of a Brazilian School Hospital. The functionality, Positive and Negative SRC strategies and DS were evaluated. The IC had high average use of SRC, with Positive SRC being more used than Negative SRC. In the unadjusted regression model, Positive and Negative SRC were associated with DS. However, when adjusted for confounding factors, only Negative SRC remained associated with DS. The IC had used their religious and spiritual beliefs as a way to cope with the stress that comes from caring for hospitalized older adults. Although the positive strategy use of these beliefs was more common, only the negative strategies were associated with a higher DS.  相似文献   
50.
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