Sampling and analysis of PAH and oxygenated PAH in diesel exhaust and ambient air

Polycyclic Aromatic Hydrocarbons (PAH) and their oxygenated derivatives occur in particles or in the vapour phase in the atmosphere. Some of these compounds, particularly the PAH, are known as strong carcinogens and/or mutagens. Emissions from diesel engines are an important source of these contaminants in urban air. In this work, the chemical composition of diesel particles was studied from two different perspectives: the gaz/particule partitioning and the different size fractions of these compounds. A dilution tunnel, with a diesel car connected, was built for the purpose of this study. Measurements were carried out near a motorway in Paris for comparison to the tunnel test results. The results show, firstly, that the gaseous phase of the PAH is predominant (up to 20 times) with respect to the particulate phase, and that the PAH and their derivatives are mainly adsorbed in the very fine particulate fraction (for particle size under 0.4 urn). Secondly, the oxygenated PAH, neglected in the majority of previous studies, are predominant with respect to the PAH

Beyond " clear wood " : exploring the structure-properties of figured woods and of woods with strong gradients selected in craftsmanship

National audienceThis poster presents a beginning Ph.D. research. The subject focuses on an apparent paradox between different approaches to wood: from the viewpoint of engineering sciences (as from industrial uses), "good" wood is orthotropic, well oriented and homogeneous, singularities are considered as "defects". In standing tree, as the living organism, homogeneity can be considered as a singularity. And from the viewpoint of artisanal usage, either heterogeneity or singularities or both can be considered as "defects", on the contrary, as "qualities" according to the considered uses. The subject, therefore, concerns the permeability between the concepts of "defect" and "quality". It aims to fulfil the gaps in knowledge of heterogeneous woods (figured woods, grain deviations, pieces including gradients, etc.). It also concerns usage-function adequacy and should open the way to a better identification of "precious" wood (e.g., figured) and to a better valorisation of wood types that are usually underestimated. The scientific question is posed, different from most current research work on "clear wood", for seldom addressed in wood mechanics: How to explain the mechanical behaviour of wood with strong gradients in its properties or with grain deviations or both? Knowing that such types of wood are sought after and deliberately selected in several fields of woodcrafts. The “figured wood” is a particular concern here, because of the trade-offs between mechanical and aesthetical criteria for the choices. The main orientation of the cells does not follow the axis of the trunk, but instead the cells’ direction present more or less periodic reorientations, according to different schemes and material axes (Beal and Davis, 1977)

A 3D CFD model of the interstitial fluid pressure and drug distribution in heterogeneous tumor nodules during intraperitoneal chemotherapy

Although intraperitoneal chemotherapy (IPC) has evolved into an established treatment modality for patients with peritoneal metastasis (PM), drug penetration into tumor nodules remains limited. Drug transport during IPC is a complex process that depends on a large number of different parameters (e.g. drug, dose, tumor size, tumor pressure, tumor vascularization). Mathematical modeling allows for a better understanding of the processes that underlie drug transport and the relative importance of the parameters influencing it. In this work, we expanded our previously developed 3D Computational Fluid Dynamics (CFD) model of the drug mass transport in idealized tumor nodules during IP chemotherapy to include realistic tumor geometries and spatially varying vascular properties. DCE-MRI imaging made it possible to distinguish between tumorous tissues, healthy surrounding tissues and necrotic zones based on differences in the vascular properties. We found that the resulting interstitial pressure profiles within tumors were highly dependent on the irregular geometries and different zones. The tumor-specific cisplatin penetration depths ranged from 0.32 mm to 0.50 mm. In this work, we found that the positive relationship between tumor size and IFP does not longer hold in the presence of zones with different vascular properties, while we did observe a positive relationship between the percentage of viable tumor tissue and the maximal IFP. Our findings highlight the importance of incorporating both the irregular tumor geometries and different vascular zones in CFD models of IPC

Synergistic Effect of Cardiovascular Risk Factors on Necrotic Core in Coronary Arteries A Report From the Global Intravascular Radiofrequency Data Analysis Registry

ObjectivesThis study explored whether an individual or a cluster of risk factors affects the extent of necrotic core (NC) assessed by intravascular ultrasound (IVUS) radiofrequency data (RFD) analysis.BackgroundSeveral systemic diseases contribute to the development of coronary artery disease.MethodsThe Global Intravascular Radiofrequency Data Analysis Registry was a prospective, multicenter, nonrandomized database that enrolled 990 patients with coronary artery disease in whom 1 major coronary artery was imaged by IVUS-RFD. For the multivariable analysis, the population was divided into 4 classes: young women, young men (both ≤62 years), old women, and old men (>62 years). Mean NC area was categorized as 1: top quartile (≥0.62 mm2) or as 0: lower 3 quartiles.ResultsYoung patients had less NC compared with older patients (0.40 ± 0.36 mm2 of NC vs. 0.50 ± 0.46 mm2 in old patients, p = 0.0007). Nondiabetic patients had less NC than diabetic patients (0.43 ± 0.41 mm2 of NC vs. 0.51 ± 0.44 mm2 in diabetic patients, p = 0.02). The NC area was lower in normotensive patients (0.40 ± 0.36 mm2) than in hypertensive patients (0.48 ± 0.44 mm2) (p = 0.02). In the bivariate analysis, age, hypertension, diabetes, and prior coronary artery bypass graft were statistically significant, however in logistic regression analysis, only age (odds ratio [OR]: 1.023, 95% confidence interval [CI]: 1.009 to 1.037, p = 0.001) and diabetes (OR: 1.636, 95% CI: 1.174 to 2.279, p = 0.004) remained statistically significant. In a per-class logistic regression analyses including only diabetes as covariate, the OR in young women was 2.1 (95% CI: 0.77 to 6.0, p = 0.14), in young men the OR was 1.6 (95% CI: 0.90 to 2.7, p = 0.11), in old women the OR was 2.3 (95% CI: 1.09 to 4.9, p = 0.03), and in old men the OR was 1.6 (95% CI: 0.96 to 2.7, p = 0.07). Further, when only patients with diabetes and hypertension were included, young men (OR: 2.0, p = 0.041), old women (OR: 3.04, p = 0.046), and old men (OR: 2.2, p = 0.025) were significant.ConclusionsIndividually and collectively, age and diabetes mellitus are associated with an increase in NC by IVUS-RFD analysis

An « all around » version of the Mac Gregor free flap.

editorial reviewedSuite à l’apparition de nombreux lambeaux de couverture au cours des dernières décennies, le lam- beau de Mac Gregor sous sa forme libre est de moins en moins utilisé mais trouve encore sa place aujourd’hui dans certains cas complexes avec des pertes de substance étendues. Ce rapport décrit un cas inhabituel de large cou- verture tissulaire par un lambeau libre de type Mac Gregor en «all around flap» chez une victime d’une brûlure éten- due du membre supérieur gauche survenue le 08/08/1997 et responsable d’un flessum progressif du poignet et d’une hyperextension des doigts avec une perte complète de leur mobilité. L’intervention se fait en un temps avec une large libération des zones cicatricielles du poignet et de la main et la réalisation du lambeau inguinal libre en «all around flap». Nous discutons ici du type de lambeau, de l’approche chirurgicale, des différents avantages et incon- vénients par rapport à d’autres lambeaux connus et des possibles complications du lambeau inguinal libre de Mac Gregor.Given the appearance of a good number of cover flaps in recent decades, the Mac Gregor flap in its free form is used less and less but still finds its place today in cer- tain complex cases with extensive loss of substance. This report describes an unusual case of wide tissue coverage by «all around» flap by Mac Gregor technique in a victim of an extensive burn of the left upper limb which occurred on 08/08/1997 and was responsible for a progressive fles- sum of the wrist and a hyperextension of the fingers with a complete loss of their mobility. The intervention is done in one step with a wide release of the scarred areas of the wrist and hand and the realization of the free inguinal flap in «all around». Here we discuss the type of flap, the surgi- cal approach, the different advantages and disadvantages compared to other known flaps and the possible complica- tions of the Mac Gregor free inguinal flap

Decreased coronary flow reserve in hypertrophic cardiomyopathy is related to remodeling of the coronary microcirculation

BACKGROUND: Ischemia occurs frequently in hypertrophic cardiomyopathy (HCM) without evidence of epicardial stenosis. This study evaluates the hypothesis that the occurrence of ischemia in HCM is related to remodeling of the coronary microcirculation. METHODS AND RESULTS: End-diastolic septal wall thickness was significantly increased in patients with HCM (25.8+/-2.9 mm) in comparison with cardiac transplant recipients (control subjects: 11.4+/-3.0 mm; P<0.05). Although the diameter of the left anterior descending coronary artery was similar in both groups (3.0+/-0.8 versus 3.0+/-0.5 mm, P=NS), the coronary resistance reserve (CRR=CRRbasal/CRRhyperemic), corrected for extravascular compression (end-diastolic left ventricular pressure), was reduced to 1.5+/-0.6 in HCM (P<.05; control, 2.6+/-0.8). Arteriolar lumen (AL) divided by wall area was lower in HCM (21+/-5% versus 30+/-4%; P<.05), and capillary density tended to decrease (from 1824+/-424 to 1445+/-513 per mm2, P=.11) in HCM. CRR was linearly related to normalized AL according to the formula CRR=O.1 AL-0.45 (r=.57; P<.05). Further analysis revealed that CRR, AL, and capillary density were all linearly related to the degree of hypertrophy. CONCLUSIONS: Decrements in CRR were related to changes of the coronary microcirculation. Both the decrease in CRR and these changes in the coronary microcirculation were related to the degree of hypertrophy. All these factors might contribute to the well-known occurrence of ischemia in this patient group