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991.
AIM: To derive and validate a score for the prediction of mid-term bleeding events following discharge for myocardial infarction (MI).METHODS: One thousand and fifty patients admitted for MI and followed for 19.9 ± 6.7 mo were assigned to a derivation cohort. A new risk model, called BLEED-MI, was developed for predicting clinically significant bleeding events during follow-up (primary endpoint) and a composite endpoint of significant hemorrhage plus all-cause mortality (secondary endpoint), incorporating the following variables: age, diabetes mellitus, arterial hypertension, smoking habits, blood urea nitrogen, glomerular filtration rate and hemoglobin at admission, history of stroke, bleeding during hospitalization or previous major bleeding, heart failure during hospitalization and anti-thrombotic therapies prescribed at discharge. The BLEED-MI model was tested for calibration, accuracy and discrimination in the derivation sample and in a new, independent, validation cohort comprising 852 patients admitted at a later date.RESULTS: The BLEED-MI score showed good calibration in both derivation and validation samples (Hosmer-Lemeshow test P value 0.371 and 0.444, respectively) and high accuracy within each individual patient (Brier score 0.061 and 0.067, respectively). Its discriminative performance in predicting the primary outcome was relatively high (c-statistic of 0.753 ± 0.032 in the derivation cohort and 0.718 ± 0.033 in the validation sample). Incidence of primary/secondary endpoints increased progressively with increasing BLEED-MI scores. In the validation sample, a BLEED-MI score below 2 had a negative predictive value of 98.7% (152/154) for the occurrence of a clinically significant hemorrhagic episode during follow-up and for the composite endpoint of post-discharge hemorrhage plus all-cause mortality. An accurate prediction of bleeding events was shown independently of mortality, as BLEED-MI predicted bleeding with similar efficacy in patients who did not die during follow-up: Area Under the Curve 0.703, Hosmer-Lemeshow test P value 0.547, Brier score 0.060; low-risk (BLEED-MI score 0-3) event rate: 1.2%; intermediate risk (score 4-6) event rate: 5.6%; high risk (score ≥ 7) event rate: 12.5%.CONCLUSION: A new bedside prediction-scoring model for post-discharge mid-term bleeding has been derived and preliminarily validated. This is the first score designed to predict mid- term hemorrhagic risk in patients discharged following admission for acute MI. This model should be externally validated in larger cohorts of patients before its potential implementation.  相似文献   
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The present work reports the detection of the first case of nosocomial Klebsiella oxytoca producing class A carbapenemase KPC-2 in Brazil. The isolate KPN106 carried a 65-kb IncW-type plasmid that harbors the blaKPC gene and Tn4401b. Moreover, we detected the presence of a class 1 integron containing a new allele, arr-8, followed by a 5′-truncated dhfrIIIc gene. In view of the recent results, we emphasize the high variability of the bacterial and genetic hosts of this resistance determinant.  相似文献   
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BackgroundIn the phase III MDS-005 study of patients with lower-risk, non-del(5q) myelodysplastic syndromes, lenalidomide was associated with a higher rate of ≥ 8 weeks red blood cell transfusion independence (RBC-TI) compared with placebo, but also with a higher risk of hematologic adverse events (AEs).Patients and MethodsThis analysis evaluated the ratio of clinical benefit-risk in patients treated with lenalidomide or placebo, and assessed the effect of lenalidomide dose reductions on response. Clinical benefit was a composite endpoint defined as RBC-TI, transfusion reduction ≥ 4 units packed red blood cells, hemoglobin increase ≥ 1.5 g/dL, or cytogenetic response.ResultsThe rate of clinical benefit was higher with lenalidomide than with placebo (31.9% vs. 3.8%). The ratio of response (RBC-TI and clinical benefit) to risk (hematologic AEs) favored lenalidomide over placebo. Patients who underwent ≥ 1 lenalidomide dose reduction had a longer duration of treatment, received a higher cumulative dose, and were more likely to experience clinical benefit versus patients without dose reductions.ConclusionDespite the occurrence of hematologic AEs, the overall benefit-risk profile supported lenalidomide treatment. Appropriate management of hematologic AEs by dose reductions may help patients with myelodysplastic syndromes to remain on treatment and achieve clinical benefit.  相似文献   
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Background Myofibroblasts (MF) are mesenchymal cells with features of both fibroblasts and smooth muscle cells. Although these are usually reactive cells, they can lead to myofibroblastic tumors that may share clinical and histomorphological characteristics but with different prognosis. The aim of this study is to perform a histomorphological evaluation as well as to compare and evaluate two different cell proliferation immunomarkers and two endothelial markers in a group of oral and maxillofacial myofibroblastic lesions (MFL).Material and Methods Cross-sectional and retrospective study. Demographic, clinical, histomorphological and immunohistochemical characteristics of 39 cases of MFL were analyzed. Immunohistochemical reactions were performed with the Ki67, MCM2, CD34 and CD105 antibodies. Kruskal-Wallis test and Spearman correlation analysis were used.Results Four cases of nodular fasciitis (NF), 18 myofibromas (My), 6 desmoplastic fibromas (DF), 7 inflammatory myofibroblastic tumors (IMT) and 4 myofibroblastic sarcomas (MFS) were studied. There were twenty women (51.2%); the median age was 13 [Q1-Q3: 8-24] years and most cases occurred in the mandible (48.7%). A statistically significant difference with MCM2 immunostaining (p=0.0221) was observed between the MFL; furthermore, a correlation between CD34 and CD105 immunostaining in NF (p <0.0001) and IMT (p=0.0408), between MCM2 and CD34 in IMT (p=0.0362) and between MCM2 and CD105 in MFS (p <0001) were found.Conclusions MCM2 immunostaining could assess more clearly the cell growth fraction in MFL. The correlation between MCM2 and CD34 in IMT and between MCM2 and CD105 in MFS are indicative of the high activity of these lesions. These results emphasize the importance of the studied immunohistochemistry markers as possible tools for a better characterization of some of the MFL. Key words:Nodular fasciitis, myofibroma, desmoplastic fibroma, inflammatory myofibroblastic tumor, myofibroblastic sarcoma.  相似文献   
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The early diagnosis of and intervention in vitamin B12 deficiency in exclusively breastfed infants by mothers with low vitamin B12 is crucial in preventing possible irreversible neurologic damage, megaloblastic anemia, and failure to thrive. We assess the usefulness of the early detection of asymptomatic B12 deficiency related to acquired conditions and highlight the importance of monitoring serum vitamin B12 levels during pregnancy. We describe demographic, clinical, dietary, and biochemical data, including the evolution of a vitamin B12 deficiency’s functional biomarkers. We enrolled 12 newborns (5 males) with an age range of 1–2 months old that were exclusively breastfed and asymptomatic. These cases were referred to our metabolic unit due to alterations in expanded newborn screening: high levels of methylmalonic acid and/or total homocysteine (tHcy). All mothers were under a vegetarian diet except three who had abnormal B12 absorption, and all presented low or borderline serum B12 level and high plasma levels of tHcy. Supplementation with oral vitB12 re-established the metabolic homeostasis of the mothers. In infants, therapy with an intramuscular injection of 1.0 mg hydroxocobalamin led to the rapid normalization of the metabolic pattern, and a healthy outcome was observed. Acquired B12 deficiency should be ruled out before proceeding in a differential diagnosis of cobalamin metabolism deficits, methylmalonic acidemia, and homocystinuria.  相似文献   
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