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Background: In the cuttlefish Sepia officinalis, iridescence is known to play a role in patterning and communication. In iridophores, iridosomes are composed of reflectins, a protein family, which show great diversity in all cephalopod species. Iridosomes are established before hatching, but very little is known about how these cells are established, their distribution in embryos, or the contribution of each reflectin gene to iridosome structures. Results: Six reflectin genes are expressed during the development of iridosomes in Sepia officinalis. We show that they are expressed in numerous parts of the body before hatching. Evidence of the colocalization of two different genes of reflectin was found. Curiously, reflectin mRNA expression was no longer detectable at the time of hatchling, while reflectin proteins were present and gave rise to visible iridescence. Conclusion: These data suggest that several different forms of reflectins are simultaneously used to produce iridescence in S. officinalis and that mRNA production and translation are decoupled in time during iridosome development. Developmental Dynamics 242:550–561, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Left ventricular (LV) remodeling after myocardial infarction (MI) indicates a high risk of heart failure and death, but LV remodeling remains difficult to predict. Biomarkers may help to refine risk stratification for a more personalized medical approach. They may also shed light on the pathophysiologic processes involved. We performed a systematic review of the published evidence about the association of circulating biomarkers with LV remodeling after MI. We selected 59 publications. Overall, these studies examined 112 relations between 52 different biomarkers and LV remodeling. The biomarkers most consistently associated with LV remodeling were involved in extracellular matrix turnover or neurohormonal activation: matrix metalloproteinase-9, collagen peptides, and B-type natriuretic peptide. This review underscores the vitality of the research on LV remodeling but concludes that the ideal biomarker has not yet been identified. To reach this goal, future studies will have to be larger, have standardized imaging end points, and include replication populations to define optimal cutoffs for LV remodeling prediction. Cardiovascular magnetic resonance appears to be the best technique for LV remodeling assessment but its current availability may be a concern for recruitment for multicenter studies. Recent technologic advances will probably yield new candidate biomarkers of LV remodeling. Tests are necessary to determine whether a multimarker approach would significantly improve risk prediction.  相似文献   
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Marrow cells from patients with higher-risk myelodysplastic syndrome (MDS) exhibit constitutive nuclear factor (NF)-κB activation. The proteasome inhibitor, bortezomib, has limited efficacy as a single agent in acute myeloid leukaemia. Its activity on leukaemic cell lines is potentiated by chemotherapy. We treated 43 higher-risk MDS patients with bortezomib (1·5 mg/m(2) , days 1, 4, 8 and 11) and low dose cytarabine arabinoside (LDAC; 10 mg/m(2) , then 20 mg/m(2) from days 1-14), every 28 d for four cycles. Median follow-up was 29·7 months. Responses were seen in 12 of the 43 patients (28%), including complete response (CR, n = 1), marrow-CR (n = 3), partial response (PR, n = 5) and haematological improvement (HI, n = 3). Responses were seen in 12 (36%) of the 33 previously untreated patients (11% CR, 13% PR, 2·5% HI), compared to none in the 12 previously treated patients (P < 0·01). Responders had better overall survival (median 18·2 vs. 10 months). One CR and 3 marrow-CRs were seen in patients with complex karyotypes. Main toxicity was haematological, responsible for infection in six patients and bleeding in 3. Three patients with Grade 1-2 pre-treatment haematotoxicity developed Grade 3-4 toxicity. Neuropathy was seen in 12% of patients. The addition of bortezomib to LDAC in higher-risk MDS may improve results obtained with LDAC alone, especially in patients with unfavourable karyotypes.  相似文献   
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Background and aim of the study: Postoperative pericardial effusion is frequent and can be complicated by cardiac tamponade. Although the different drainage techniques are well described in the setting of medical effusion, there is not a standard postoperative effusion treatment. The aim of this work was to assess the feasibility and effectiveness of the percutaneous pericardial drainage. Methods: This a retrospective study involving 197 patients from 1990 to 2008. Drainage was performed by subxiphoid puncture (91.9%) or left parasternal puncture (8.1%) between 3 and 690 days following a cardiac procedure via median sternotomy. Effusion thickness was at least 10 mm in the subcostal echocardiography view. Results: No deaths directly related to the procedure were observed. Complete and enduring drainage was achieved in 158 patients (80.2%). The procedure failed for 22 patients (11.2%) because no fluid was drained in 14 cases (7.1%) and a right ventricular puncture in 8 cases (4.1%). Recurrence of the effusion, which occurred for 17 patients (8.6%), was more frequent if an effusion of more than 5 mm persisted after the first drainage (P = 0.024) and if the drainage was performed outside the operating room because of emergency (P = 0.046). Risk factors for mortality were recurrence of the effusion (P = 0.04) and drainage performed outside the operating room (P = 0.007). Conclusions: Percutaneous pericardial drainage is effective to treat postoperative pericardial effusion. When the effusion is thicker than 10 mm and accessible, it can be the initial strategy and surgical drainage can serve as an alternate strategy in case of failure and complications of this procedure. (J Interven Cardiol 2012;25:95–101)  相似文献   
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Impact of Recalls on ICD Utilization . Introduction: The study was designed to evaluate the feasibility and performance of right ventricular (RV) mid‐septal versus apical implantable defibrillator (ICD) lead placement. Methods and Results: SEPTAL is a randomized, noninferiority trial, which randomly assigned patients to implantation of ICD leads in the RV mid‐septum versus apex, with a primary objective of comparing the implant success rate of implant at each site, based on strict electrical predefined criteria. We also compared the (1) pacing lead characteristics, (2) rates of appropriate and inappropriate ICD therapies, and (3) all‐cause mortality between the 2 sites at 1 year. The trial enrolled 215 patients (mean age = 59.7 ± 12.4 years, mean LVEF = 34.0 ± 14.2%, 84.2% men), of whom 148 (68.8%) presented with ischemic heart disease. The ICD indication was primary prevention in 117 patients (54.4%). The lead was successfully implanted in 96/107 patients (89.7%) assigned to the RV mid‐septum, and in 99/108 (91.7%) assigned to the apex (ns). The 1‐year rate of lead‐related adverse events was similar in both groups. A total of 8 first inappropriate ICD therapies (7.9%) were delivered in the RV mid‐septal group, versus 8 (7.8%) in the apical group (ns), while first appropriate therapies were delivered to 22 (21.4%) and 24 patients (23.8%), respectively (ns). All‐cause mortality was 7.9% in the RV mid‐septal versus 2.9% in the RV apical group (ns). Conclusion: This study confirmed the technical feasibility and noninferior performance of ICD leads implanted in the RV mid‐septum versus the apex. (J Cardiovasc Electrophysiol, Vol. 23, pp. 853‐860, August 2012)  相似文献   
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