Cancer cells escape cytotoxic effects of anticancer drugs by a process known as multidrug resistance (MDR). Identification of cell status by less time-consuming methods can be extremely useful in patient management and treatment. This study aims at evaluating the potentials of vibrational spectroscopic methods to perform cell typing and to differentiate between sensitive and resistant human cancer cell lines, in particular those that exhibit the MDR phenotype. Micro-Raman and Fourier transform infrared (FTIR) spectra have been acquired from the sensitive promyelocytic HL60 leukemia cell line and two of its subclones resistant to doxorubicin (HL60/DOX) and daunorubicin (HL60/ DNR), and from the sensitive MCF7 breast cancer cell line and its MDR counterpart resistant to verapamil (MCF7/VP). Principal components analysis (PCA) was employed for spectral comparison and classification. Our data show that cell typing was feasible with both methods, giving two distinct clusters for HL60-and MCF7-sensitive cells. In addition, phenotyping of HL60 cells, i.e., discriminating between the sensitive and MDR phenotypes, was attempted by both methods. FTIR could not only delineate between the sensitive and resistant HL60 cells, but also gave two distinct clusters for the resistant cells, which required a two-step procedure with Raman spectra. In the case of MCF7 cell lines, both the sensitive and resistant phenotypes could be differentiated very efficiently by PCA analysis of their FTIR and Raman point spectra. These results indicate the prospective applicability of FTIR and micro-Raman approaches in the differentiation of cell types as well as characterization of the cell status, such as the MDR phenotype exhibited in resistant leukemia cell lines like HL60 and MCF7.

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To date, endovascular repair of thoracic dissections is a reality, associated with acceptable morbidity and mortality. We present the case of a 72-year-old woman presenting a retrograde aortic dissection at the postoperative day 12, after an endovascular repair for a 60-mm thoracic dissecting aneurysm. Two years earlier, she had presented an uncomplicated thoracoabdominal type B aortic dissection between the isthmic aorta and the iliac bifurcation. Despite an acceptable blood pressure control, a 62-mm thoracic dissecting aneurysm was observed on the 24-month CT-scan. Due to a chronic obstructive pulmonary disease, we chose the endovascular approach to exclude the thoracic entry tear leading to the complete false lumen thrombosis around the endoprosthesis. However, the inferior part of the false lumen remained patent due to a second abdominal entry tear. The initial outcome was uneventful but the patient presented a sudden death syndrome twelve days after the endovascular repair. During the autopsy, we discovered an intrapericardial rupture of a retrograde dissection, starting at the level of the proximal bare spring of the endoprosthesis. We discuss some important technical details to improve the safety, and to reduce the risk of immediate or delayed complications.

Continuous renal replacement therapy is particularly suited in the setting of acute renal failure, occurring after cardiac surgery, in patients requiring extracorporeal life support (ECLS) or membrane oxygenation. In such patients, temporary catheters are not necessary since the circuit of haemodialysis or haemofiltration may be connected on the ECLS cannulae. We report how to modify a classical ECLS circuit to connect directly the haemodialysis (Prismaflex device, Gambro-Hospal, Lyon, France) to the ECLS. We also detail parameters used to initiate the haemodialysis. Actually, we modify all our ECLS circuits as described here, at implantation time, allowing rapid haemodialysis initiations. Since 2004, 21 patients have been treated, as described here, without supplemental mortality or related complication.

Journal of BIOPHOTONICSThe advent of moderate dilatations in ascending aortas is often accompanied by structural modifications of the main components of the aortic tissue, elastin and collagen. In this study, we have undertaken an approach based on FTIR microscopy coupled to a curve-fitting procedure to analyze secondary structure modifications in these proteins in human normal and pathological aortic tissues. We found that the outcome of the aortic pathology is strongly influenced by these proteins, which are abundant in the media of the aortic wall, and that the advent of an aortic dilatation is generally accompanied by a decrease of parallel b-sheet structures. Elastin, essentially composed of b-sheet structures, seems to be directly related to these changes and therefore indicative of the elastic alteration of the aortic wall. Conventional microscopy and confocal fluorescence microscopy were used to compare FTIR microscopy results with the organization of the elastic fibers present in the tissues. This in-vitro study on 6 patients (three normal and three pathologic), suggests that such a spectroscopic marker, specific to aneurismal tissue characterization, could be important information for surgeons who face the dilemma of moderate aortic tissue dilatation of the ascending aortas.Infrared spectroscopy and imaging was applied to analyse Human thoracic ascending aortas with the aim to highlight the protein secondary structure reorganisation after an aneurism outcome. We used a curve-fitting procedure to visualise modifications in the protein spectral profile where alteration of b structures in pathological aortas could be detected. Our spectroscopic observations on tissue sections corroborated with confocal fluorescence microscopy clearly demonstrating that elastic fibres of aortic wall are strongly altered. Elastin appears as the privileged target during the pathological process.

FTIR microspectroscopy has shown to be a proven tool in the investigation of many tissue types. We have used this spectroscopic approach to analyse structural differences between normal and aneurismal aortic tissues and also aortas from patients with congenital anomalies like aortic bicuspid valves. Spectral analysis showed important variations in amide I and II regions, related to changes in alpha-helix and beta-sheet secondary structure of proteins that seem to be correlated to structural modifications of collagen and elastin. These proteins are the major constituents of the aortic wall associated to smooth muscular cells. The amide regions have thus been identified as a marker of structural modifications related to these proteins whose modifications can be associated to a given aortic pathological situation. Both univariate (total absorbance image and band ratio) and multivariate (principal components analysis) analyses of the spectral information contained in the infrared images have been performed. Differences between tissues have been identified by these two approaches and allowed to separate each group of aortic tissues. However, with univariate band ratio analysis, the pathological group was found to be composed of samples from aneurismal aortas associated or not with an aortic bicuspid valve. In contrast, PCA was able to separate these two types of aortic pathologies. For other groups, PCA and band ratio analysis can differentiate between normal, aneurismal, and none dilated aortas from patients with a bicuspid aortic valve.

Processing of multispectral images is becoming an important issue, especially in terms of data mining for disease diagnosis. We report here an original image analysis procedure developed in order to compare 42 infrared multispectral images acquired on human ascending aortic healthy and pathological tissues. Each image contained about 2500 infrared absorption spectra, each composed of 1641 variables (wavenumbers). To process this large data set, we have restricted the spectral window used to the 1800-950 cm(-1) spectral range and selected 100 spectra from the aortic media, which is the most altered part of the aortic tissue in aneurysms. Prior to this selection, a spectral quality test was performed to eliminate 'bad' spectra. Our data set was first subjected to a discriminant analysis, which allowed separation of aortic tissues in two groups corresponding respectively to normal and aneurysmal states. Then a K-means analysis, based on 20 groups, allowed reconstruction of infrared images using false-colours and discriminated between pathological and healthy tissues. These results demonstrate the usefulness of such data processing methods for the analysis and comparison of a set of spectral images.

Background: Sternal wound infection (SWI) is a major complication occurring often after coronary artery bypass grafting (CABG) using bilateral internal mammary artery (BIMA) grafts. The aim of this study is to assess whether such a risk may be reduced by using incision negative pressure wound therapy (INPWT). Methods: Data on patients undergoing isolated CABG using BIMA grafts at the Reims University Hospital, France, from 2013 to 2016 without or with INPWT was prospectively collected.  Results: INPWT was used in 161 patients and conventional sterile wound dressing was used in 266 patients. Propensity score matching resulted in 128 pairs with similar characteristics. SWIs were similarly distributed between the conventional sterile wound dressing (10.9%) and the INPWT cohorts (10.2%) (P = 1.00). Patients treated with INPWT had a lower rate of deep SWI/mediastinitis than patients who had conventional sterile dressing (5.5% versus 10.2%, P = .210), but the difference did not reach statistical significance. Tests for interaction confirmed these findings in different patient subgroups. Conclusion: The routine use of INPWT may not significantly reduce the risk of SWI in patients undergoing BIMA grafting. In view of previous reports showing a benefit with the use of this method, a large randomized study is justified to assess the efficacy of INPWT in patients undergoing cardiac surgery.