Showing papers by "Université Nantes Angers Le Mans published in 2015"

Effect of a retrievable inferior vena cava filter plus anticoagulation vs anticoagulation alone on risk of recurrent pulmonary embolism: a randomized clinical trial.

Abstract: Importance Although retrievable inferior vena cava filters are frequently used in addition to anticoagulation in patients with acute venous thromboembolism, their benefit-risk ratio is unclear. Objective To evaluate the efficacy and safety of retrievable vena cava filters plus anticoagulation vs anticoagulation alone for preventing pulmonary embolism recurrence in patients presenting with acute pulmonary embolism and a high risk of recurrence. Design, Setting, and Participants Randomized, open-label, blinded end point trial (PREPIC2) with 6-month follow-up conducted from August 2006 to January 2013. Hospitalized patients with acute, symptomatic pulmonary embolism associated with lower-limb vein thrombosis and at least 1 criterion for severity were assigned to retrievable inferior vena cava filter implantation plus anticoagulation (filter group; n = 200) or anticoagulation alone with no filter implantation (control group; n = 199). Initial hospitalization with ambulatory follow-up occurred in 17 French centers. Interventions Full-dose anticoagulation for at least 6 months in all patients. Insertion of a retrievable inferior vena cava filter in patients randomized to the filter group. Filter retrieval was planned at 3 months from placement. Main Outcomes and Measures Primary efficacy outcome was symptomatic recurrent pulmonary embolism at 3 months. Secondary outcomes were recurrent pulmonary embolism at 6 months, symptomatic deep vein thrombosis, major bleeding, death at 3 and 6 months, and filter complications. Results In the filter group, the filter was successfully inserted in 193 patients and was retrieved as planned in 153 of the 164 patients in whom retrieval was attempted. By 3 months, recurrent pulmonary embolism had occurred in 6 patients (3.0%; all fatal) in the filter group and in 3 patients (1.5%; 2 fatal) in the control group (relative risk with filter, 2.00 [95% CI, 0.51-7.89]; P = .50). Results were similar at 6 months. No difference was observed between the 2 groups regarding the other outcomes. Filter thrombosis occurred in 3 patients. Conclusions and Relevance Among hospitalized patients with severe acute pulmonary embolism, the use of a retrievable inferior vena cava filter plus anticoagulation compared with anticoagulation alone did not reduce the risk of symptomatic recurrent pulmonary embolism at 3 months. These findings do not support the use of this type of filter in patients who can be treated with anticoagulation. Trial Registration clinicaltrials.gov Identifier:NCT00457158

Enhancing the absorption properties of acoustic porous plates by periodically embedding Helmholtz resonators

Abstract: This paper studies the acoustical properties of hard-backed porous layers with periodically embedded air filled Helmholtz resonators. It is demonstrated that some enhancements in the acoustic absorption coefficient can be achieved in the viscous and inertial regimes at wavelengths much larger than the layer thickness. This enhancement is attributed to the excitation of two specific modes: Helmholtz resonance in the viscous regime and a trapped mode in the inertial regime. The enhancement in the absorption that is attributed to the Helmholtz resonance can be further improved when a small amount of porous material is removed from the resonator necks. In this way the frequency range in which these porous materials exhibit high values of the absorption coefficient can be extended by using Helmholtz resonators with a range of carefully tuned neck lengths.

Seismic vulnerability assessment of urban environments in moderate-to-low seismic hazard regions using association rule learning and support vector machine methods

Abstract: The estimation of the seismic vulnerability of buildings at an urban scale, a crucial element in any risk assessment, is an expensive, time-consuming, and complicated task, especially in moderate-to-low seismic hazard regions, where the mobilization of resources for the seismic evaluation is reduced, even if the hazard is not negligible. In this paper, we propose a way to perform a quick estimation using convenient, reliable building data that are readily available regionally instead of the information usually required by traditional methods. Using a dataset of existing buildings in Grenoble (France) with an EMS98 vulnerability classification and by means of two different data mining techniques—association rule learning and support vector machine—we developed seismic vulnerability proxies. These were applied to the whole France using basic information from national databases (census information) and data derived from the processing of satellite images and aerial photographs to produce a nationwide vulnerability map. This macroscale method to assess vulnerability is easily applicable in case of a paucity of information regarding the structural characteristics and constructional details of the building stock. The approach was validated with data acquired for the city of Nice, by comparison with the RiskUE method. Finally, damage estimations were compared with historic earthquakes that caused moderate-to-strong damage in France. We show that due to the evolution of vulnerability in cities, the number of seriously damaged buildings can be expected to double or triple if these historic earthquakes were to occur today.

Iron metabolism: a double-edged sword in the resistance of glioblastoma to therapies

Abstract: Glioblastoma (GBM), the deadliest primary tumor of the central nervous system (CNS), is a clear illustration of the resistance of cancer cells to conventional therapies. Application of combinatorial strategies able to overcome pivotal factors of GBM resistance, particularly within the resection margins, represents an essential issue. This review focuses on the role of iron metabolism in GBM progression and resistance to therapy, and the impact of its pharmaceutical modulation on the disease. Iron, through its involvement in many biological processes, is a key factor in the control of cell behavior and cancer biology. Therefore, targeting cellular iron signaling or taking advantage of its dysregulation in cancer cells may lead to new opportunities for improving treatments and drug delivery in GBM.

New practical definitions for the diagnosis of autosomal recessive spastic ataxia of Charlevoix-Saguenay

Abstract: Objective Autosomal recessive spastic ataxia of Charlevoix–Saguenay (ARSACS) is caused by mutations in the SACS gene. SACS encodes sacsin, a protein whose function remains unknown, despite the description of numerous protein domains and the recent focus on its potential role in the regulation of mitochondrial physiology. This study aimed to identify new mutations in a large population of ataxic patients and to functionally analyze their cellular effects in the mitochondrial compartment. Methods A total of 321 index patients with spastic ataxia selected from the SPATAX network were analyzed by direct sequencing of the SACS gene, and 156 patients from the ATAXIC project presenting with congenital ataxia were investigated either by targeted or whole exome sequencing. For functional analyses, primary cultures of fibroblasts were obtained from 11 patients carrying either mono- or biallelic variants, including 1 case harboring a large deletion encompassing the entire SACS gene. Results We identified biallelic SACS variants in 33 patients from SPATAX, and in 5 nonprogressive ataxia patients from ATAXIC. Moreover, a drastic and recurrent alteration of the mitochondrial network was observed in 10 of the 11 patients tested. Interpretation Our results permit extension of the clinical and mutational spectrum of ARSACS patients. Moreover, we suggest that the observed mitochondrial network anomalies could be used as a trait biomarker for the diagnosis of ARSACS when SACS molecular results are difficult to interpret (ie, missense variants and heterozygous truncating variant). Based on our findings, we propose new diagnostic definitions for ARSACS using clinical, genetic, and cellular criteria. Ann Neurol 2015;78:871–886

Psychosocial Risk Factors, Interventions, and Comorbidity in Patients with Non-Specific Low Back Pain in Primary Care: Need for Comprehensive and Patient-Centered Care

Abstract: Non-specific low back pain (LBP) affects many people and has major socio-economic consequences. Traditional therapeutic strategies, mainly focused on biomechanical factors, have had moderate and short-term impact. Certain psychosocial factors have been linked to poor prognosis of LBP and they are increasingly considered as promising targets for management of LBP. Primary health care providers (HCPs) are involved in most of the management of people with LBP and they are skilled in providing comprehensive care, including consideration of psychosocial dimensions. This review aims to discuss three pieces of recent research focusing on psychosocial issues in LBP patients in primary care. In the first systematic review, the patients’ or HCPs’ overall judgment about the likely evolution of LBP was the factor most strongly linked to poor outcome, with predictive validity similar to that of multidimensional scales. This result may be explained by the implicit aggregation of many prognostic factors underlying this judgment and suggests the relevance of considering the patients from biopsychosocial and longitudinal points of view. The second review showed that most of the interventions targeting psychosocial factors in LBP in primary care have to date focused on the cognitive-behavioral factors, resulting in little impact. It is unlikely that any intervention focusing on a single factor would ever fit the needs of most patients; interventions targeting determinants from several fields (mainly psychosocial, biomechanical, and occupational) may be more relevant. Should multiple stakeholders be involved in such interventions, enhanced interprofessional collaboration would be critical to ensure the delivery of coordinated care. Finally, in the third study, the prevalence of psychosocial comorbidity in chronic LBP patients was not found to be significantly higher than in other patients consulting in primary care. Rather than specifically screening for psychosocial conditions, this suggests taking into account any potential comorbidity in patients with chronic LBP, as in other patients. All these results support the adoption of a more comprehensive and patient-centered approach when dealing with patients with LBP in primary care. As this condition is illustrative of many situations encountered in primary care, the strategies proposed here may benefit most patients consulting in this setting.

Sensitivity Analysis of Environmental Process Modeling in a Life Cycle Context: A Case Study of Hemp Crop Production

Abstract: The aim of this article is to develop a methodological approach allowing to assess the influence of parameters of one or more elementary processes in the foreground system, on the outcomes of a life cycle assessment (LCA) study. From this perspective, the method must be able to: (1) include foreground process modeling in order to avoid the assumption of proportionality between inventory data and reference flows; (2) quantify influences of foreground processes’ parameters (and, possibly, interactions between parameters); and (3) identify trends (either increasing or decreasing) for each parameter on each indicator in order to determine the most favorable direction for parametric variation. These objectives can be reached by combining foreground system modeling, a set of two different sensitivity analysis methods (each one providing different and complementary information), and LCA. The proposed method is applied to a case study of hemp-based insulation materials for buildings. The present study will focus on the agricultural stage as a foreground system and as a first step encompassing the entire life cycle. A set of technological recommendations were identified for hemp farmers in order to reduce the crop's environmental impacts (from –11% to –89% according to the considered impact category). One of the main limitations of the approach is the need for a detailed model of the foreground process. Further, the method is, at present, rather time-consuming. However, it offers long-term advantages given that the higher level of model detail adds robustness to the LCA results

Destination Memory for Emotional Information in Older Adults

Abstract: Background/Study Context: Destination memory, remembering the destination of the information that one tells, shows significant age-related decline. In the present paper, the authors sought to determine whether destination memory can be improved in older adults using emotional stimuli. This aim was motivated by findings showing better context memory for emotional than for neutral information in older adults. Methods: Younger and older adults were asked to tell neutral facts to three types of faces: a neutral one, an emotionally positive one, and an emotionally negative one. On a later recognition test, participants were asked to associate each previously told fact with the face to whom it was told. Results: Destination memory performance was better for facts told to negative than to positive faces, and the latter memory was better than for neutral faces in older adults. Conclusion: Older adults seem to place higher emphasis on emotional material relative to neutral faces, showing better memory for the association between statements and emotional faces.

Describing and classifying urban sound environments with a relevant set of physical indicators

Abstract: Categorization is a powerful method for describing urban sound environments. However, it has only been applied, until now, to discrete noise data collection, whereas sound environments vary continuously both in space and time. Therefore, a procedure is developed in this paper for describing the variations of urban sound environments. The procedure consists of mobile measurements, followed by a statistical clustering analysis that selects relevant noise indicators and classifies sound environments. Analysis are based on a 3 days + 1 night survey where geo-referenced noise measurements were collected over 19 1-h soundwalk periods in a district of Marseille, France. The clustering analysis showed that a limited subset of indicators is sufficient to discriminate sound environments. The three indicators that emerged from the clustering, namely, the Leq,A, the standard deviation σLeq,A, and the sound gravity spectrum SGC[50 Hz–10 kHz], are consistent with previous studies on sound environment classification. Mo...

Study of Influence of Operating Parameters on Braking Friction and Rolling Resistance

Abstract: Tire–road interaction addresses safety with respect to braking friction and energy efficiency in the context of rolling resistance. These phenomena are coherent, but their engineering solutions can be contradictory. For example, highly skid-resistant surfaces may not be ideal for fuel economy, but surfaces with low rolling resistance may be prone to skidding. Several experimental and numerical studies have investigated the individual phenomena, but insufficient attention has been paid to studying them coherently. The present study computed braking friction and rolling resistance for various operating parameters and their coherent response for each parameter with the use of a thermomechanical contact algorithm. Micromechanical finite element simulations of a rolling or braking pneumatic tire against selected asphalt concrete surfaces were performed for various operating conditions, such as tire load, inflation pressure, speed, and ambient air and pavement temperatures. The coefficients of braking friction ...

Influence of cider-making process parameters on the odourant volatile composition of hard ciders

Abstract: This study was performed to explore the relationships between some parameters of the French cider-making process and the odourant compounds of cider. Sixteen ciders were prepared on a pilot plant scale using experimental design and varying according to apple blends, pressing conditions, pre-fermentation clarification implementation and conditions, and biomass reduction during fermentation. Odourant compounds were extracted from final ciders by headspace solid-phase microextraction with a CAR/PDMS fibre, a method previously shown to provide extracts representative of the studied cider. Extracts were analysed by gas chromatography coupled with mass spectrometry and flame ionization detection. All of the parameters tested had at least a slight effect on the odourant composition and particularly on the esters, which bring fruity notes that are appreciated by consumers. Clarification and biomass reduction had a greater impact than apple blend and pressing conditions. This could be explained by the influence of the nitrogen content on fermentation rate and efficiency, which affects the production of secondary metabolites. Under the conditions tested, a juice obtained from a bitter blend of apples by a slow pressing of the pulp at low temperature, after 1 h of cuvage, clarified by keeving and fermented without biomass reduction, produced a cider with the highest quantity of esters. These results could help cider-makers enhance product quality according to consumer expectations. Copyright © 2015 The Institute of Brewing & Distilling

The role of ingredients on thermal and rheological properties of cake batters and the impact on microcake texture

Abstract: Starch is the major ingredient in cakes which are composed from flour, eggs, fat and sugar. Starch gelatinization plays an important role – together with the protein network – in defining the structure and quality of the final product. Rheology, texture and batter thermal and pasting properties were used to determine the effect of ingredients on batter and microcake (cake without bubbles) properties. The rheology of the batter was controlled by the water content which governed the phase transitions of the batter constituents. Differential scanning calorimetry clearly attested that ingredients addition shifted the gelatinization endotherm to higher temperatures. This was in agreement with the MicroViscoAmyloGraph (MVAG) measurements, where the batter ingredients addition to flour increased the pasting temperature and the peak viscosity. When 20% of the flour was replaced by the pregelatinized wheat or maize starch, a decrease in the peak viscosity and setback was observed which could explain the texture improvement. The association of these different techniques helped to better understand the effects of the different ingredients of the batter on starch properties that are important for improving the quality of these high sugar and fat content cakes.

3D Porous Architecture of Stacks of β-TCP Granules Compared with That of Trabecular Bone: A microCT, Vector Analysis, and Compression Study.

Abstract: The 3D arrangement of porous granular biomaterials usable to fill bone defects has received little study. Granular biomaterials occupy 3D space when packed together in a manner that creates a porosity suitable for the invasion of vascular and bone cells. Granules of β-TCP were prepared with either 12.5 or 25g of β-TCP powder in the same volume of slurry. When the granules were placed in a test tube, this produced 3D stacks with a high (HP) or low porosity (LP), respectively. Stacks of granules mimic the filling of a bone defect by a surgeon. The aim of this study was to compare the porosity of stacks of β-TCP granules with that of cores of trabecular bone. Biomechanical compression tests were done on the granules stacks. Bone cylinders were prepared from calf tibia plateau, constituted high density (HD) blocks. Low density (LD) blocks were harvested from aged cadaver tibias. Microcomputed tomography was used on the β-TCP granule stacks and the trabecular bone cores to determine porosity and specific surface. A vector projection algorithm was used to image porosity employing a frontal plane image which was constructed line by line from all images of a microCT stack. Stacks of HP granules had porosity (75.3 ± 0.4%) and fractal lacunarity (0.043 ± 0.007) intermediate between that of HD (resp. 69.1 ± 6.4%, p<0.05 and 0.087 ± 0.045, p<0.05) and LD bones (resp. 88.8 ± 1.57% and 0.037 ± 0.014) but exhibited a higher surface density (5.56 ± 0.11 mm2/mm3 vs. 2.06 ± 0.26 for LD, p<0.05). LP granular arrangements created large pores coexisting with dense areas of material. Frontal plane analysis evidenced a more regular arrangement of β-TCP granules than bone trabeculae. Stacks of HP granules represent a scaffold that resembles trabecular bone in its porous microarchitecture.

Evaluation of aroma profile differences between sué, sautéed, and pan-fried onions using an innovative olfactometric approach.

Abstract: Onions (Allium cepa) are widely used as a flavor agent ingredient in culinary preparations to bring specific cooked onion notes. In this study, three traditional types of preparations—sue, sauteed, and pan-fried onions—were used to investigate their differences in aroma profile. Headspace solid phase micro-extraction (HS-SPME) and gas chromatography (GC) coupled with mass spectrometry (MS), flame ionization detection (FID), and olfactometry were used to analyze the onion preparations. The study enables to identify 66 major compounds in the preparations. Among these compounds, sulfur compounds, aldehydes, and furans were the most represented. The pan-fried onion preparation distinguishes itself by the highest number of compounds represented in a large amount. This result is consistent with this mode of cooking that combines high temperature with long cooking time and favors the formation of compounds from the Maillard reaction and lipid oxidation. In comparison, the sue and sauteed preparations contain globally fewer compounds and, for most of them, in a lower amount compared to the pan-fried preparation. An innovative olfactometric approach was performed, based on a laboratory-developed software using an aroma wheel especially designed for the study of cooked onion. It enables an intuitive, efficient, and precise characterization of odor events along elution. A statistical comparison of intensities perceived for each odor detected during olfactometric analysis was used to understand the aroma balance and nuances perceived for these three traditional onion preparations. In accordance with chromatographic results, the pan-fried onion displays the highest number of odorant zones (65) associated with higher intensity scores and notably, to an enhanced perception of some Maillard compounds. Sue and sauteed onion profiles show an analog number of odorant zones (50 and 53), but the sauteed onion displays higher intensity scores and a particular contribution from pyrazines. The olfactometric approach used completes advantageously the instrumental characterization of cooked onions samples obtained by these three traditional cooking processes and reveals the essential contribution of minor compounds to the aroma of cooked onions. Particular compounds and balanced profile intensities were pointed out to explain the specific aroma nuances of traditional sue, sauteed, and pan-fried onions.

The dog as a naturally-occurring model for insulin-like growth factor type 1 receptor-overexpressing breast cancer: an observational cohort study.

Abstract: Dogs spontaneously develop invasive mammary carcinoma with a high prevalence of the triple-negative (TN) subtype (lack of ER-Estrogen Receptor and PR-Progesterone Receptor expression, lack of HER2-Human Epidermal Growth Factor Receptor 2 overexpression), making this animal model relevant for investigating new therapeutic pathways. Insulin-like growth factor Type-1 receptor (IGF1R) is frequently overexpressed in primary human breast cancers, with a growing role in the TN phenotype. The purpose of this study was to investigate the Dog as a candidate model for IGF1R-overexpressing mammary carcinoma. 150 bitches with canine mammary carcinoma (CMC) and a known 2-year follow-up were retrospectively included. IGF1R expression was assessed by immunohistochemistry (IHC) using a similar scoring system as for HER2 in breast cancer. The prognostic value of the IGF1R expression was assessed in terms of overall and specific survival as well as disease-free interval (DFI). 47 CMC (31 %) were classified as luminal and 103 (69 %) as triple-negative (TN-CMC). 41 % of CMC overexpressed IGF1R (IHC score 3+) of which 76 % were TN-CMC and 62 % grade III. IGF1R overexpression was associated with aggressive features including lymphovascular invasion, histological grade III, low ER expression and the TN phenotype. Univariate and multivariate analyses revealed that IGF1R overexpression was associated with shorter overall and specific survivals and shorter DFI in TN-CMC. IGF1R overexpression is common and related to a poor outcome in canine invasive mammary carcinoma, particularly in the triple negative subtype, as in human breast cancer. Preclinical studies using the Dog as a spontaneous animal model could be considered to investigate new therapies targeting IGF1R in triple-negative breast cancer.

Fibrosis and Hypoxia-Inducible Factor-1α–Dependent Tumors of the Soft Tissue on Loss of Von Hippel-Lindau in Mesenchymal Progenitors

Abstract: The hypoxia-inducible factor (Hif)-1α (Hif-1α) and Hif-2α (Epas1) have a critical role in both normal development and cancer. von Hippel Lindau (Vhl) protein, encoded by a tumor suppressor gene, is an E3 ubiquitin ligase that targets Hif-1α and Epas1 to the proteasome for degradation. To better understand the role of Vhl in the biology of mesenchymal cells, we analyzed mutant mice lacking Vhl in mesenchymal progenitors that give rise to the soft tissues that form and surround synovial joints. Loss of Vhl in mesenchymal progenitors of the limb bud caused severe fibrosis of the synovial joints and formation of aggressive masses with histologic features of mesenchymal tumors. Hif-1α and its downstream target connective tissue growth factor were necessary for the development of these tumors, which conversely still developed in the absence of Epas1, but at lower frequency. Human tumors of the soft tissue are a very complex and heterogeneous group of neoplasias. Our novel findings in genetically altered mice suggest that activation of the HIF signaling pathway could be an important pathogenetic event in the development and progression of at least a subset of these tumors.

Use of Vitamin K Antagonists and Brain Volumetry in Older Adults: Preliminary Results From the GAIT Study

Abstract: generally considered safe, they have some adverse effects, so their prescription must always be based on major available scientific evidence. This study confirms that PPIs are frequently prescribed without an appropriate indication, and a trend of overprescription and not underprescription was observed. It was attempted to determine the characteristics of individuals at higher risk of inappropriate PPI prescription. Age does not affect PPI appropriateness; a similar percentage of PPI inappropriateness was observed in different age groups. Similar results were found previously. The CIRS comorbidity index was not associated with inappropriate PPI prescription, in contrast to the previous study, which found a statistically significant association between these two factors. The current study found an increasing trend in wrong PPI prescription with increasing number of drugs taken daily. The association was not statistically significant, but a larger study might validate this. In conclusion, the chronic use of PPIs seems to have a high margin of safety, but doubts have been raised about possible risks associated with their long-term use. Greater attention must be paid to protect people from unnecessary adverse drug effects and to cut healthcare costs.