Impact of energy deficit calculated by a predictive method on outcome in medical patients requiring prolonged acute mechanical ventilation

To assess energy balance in very sick medical patients requiring prolonged acute mechanical ventilation and its possible impact on outcome, we conducted an observational study of the first 14 d of intensive care unit (ICU) stay in thirty-eight consecutive adult patients intubated at least 7 d. Exclusive enteral nutrition (EN) was started within 24 h of ICU admission and progressively increased, in absence of gastrointestinal intolerance, to the recommended energy of 125·5 kJ/kg per d. Calculated energy balance was defined as energy delivered − resting energy expenditure estimated by a predictive method based on static and dynamic biometric parameters. Mean energy balance was − 5439 (sem 222) kJ per d. EN was interrupted 23 % of the time and situations limiting feeding administration reached 64 % of survey time. ICU mortality was 72 %. Non-survivors had higher mean energy deficit than ICU survivors (P = 0·004). Multivariate analysis identified mean energy deficit as independently associated with ICU death (P = 0·02). Higher ICU mortality was observed with higher energy deficit (P = 0·003 comparing quartiles). Using receiver operating characteristic curve analysis, the best deficit threshold for predicting ICU mortality was 5021 kJ per d. Kaplan–Meier analysis showed that patients with mean energy deficit ≧5021 kJ per d had a higher ICU mortality rate than patients with lower mean energy deficit after the 14th ICU day (P = 0·01). The study suggests that large negative energy balance seems to be an independent determinant of ICU mortality in a very sick medical population requiring prolonged acute mechanical ventilation, especially when energy deficit exceeds 5021 kJ per d

Advances in ab-initio theory of Multiferroics. Materials and mechanisms: modelling and understanding

Within the broad class of multiferroics (compounds showing a coexistence of magnetism and ferroelectricity), we focus on the subclass of "improper electronic ferroelectrics", i.e. correlated materials where electronic degrees of freedom (such as spin, charge or orbital) drive ferroelectricity. In particular, in spin-induced ferroelectrics, there is not only a {\em coexistence} of the two intriguing magnetic and dipolar orders; rather, there is such an intimate link that one drives the other, suggesting a giant magnetoelectric coupling. Via first-principles approaches based on density functional theory, we review the microscopic mechanisms at the basis of multiferroicity in several compounds, ranging from transition metal oxides to organic multiferroics (MFs) to organic-inorganic hybrids (i.e. metal-organic frameworks, MOFs)Comment: 22 pages, 9 figure

Intracellular degradation of functionalized carbon nanotube/iron oxide hybrids is modulated by iron via Nrf2 pathway.

The in vivo fate and biodegradability of carbon nanotubes is still a matter of debate despite tremendous applications. In this paper we describe a molecular pathway by which macrophages degrade functionalized multi-walled carbon nanotubes (CNTs) designed for biomedical applications and containing, or not, iron oxide nanoparticles in their inner cavity. Electron microscopy and Raman spectroscopy show that intracellularly-induced structural damages appear more rapidly for iron-free CNTs in comparison to iron-loaded ones, suggesting a role of iron in the degradation mechanism. By comparing the molecular responses of macrophages derived from THP1 monocytes to both types of CNTs, we highlight a molecular mechanism regulated by Nrf2/Bach1 signaling pathways to induce CNT degradation via NOXjournal article2017 Jan 252017 01 25importe

Cold ablation driven by localized forces in alkali halides

Laser ablation has been widely used for a variety of applications. Since the mechanisms for ablation are strongly dependent on the photoexcitation level, so called cold material processing has relied on the use of high-peak-power laser fluences for which nonthermal processes become dominant; often reaching the universal threshold for plasma formation of ∼1 J cm-2 in most solids. Here we show single-shot time-resolved femtosecond electron diffraction, femtosecond optical reflectivity and ion detection experiments to study the evolution of the ablation process that follows femtosecond 400 nm laser excitation in crystalline sodium chloride, caesium iodide and potassium iodide. The phenomenon in this class of materials occurs well below the threshold for plasma formation and even below the melting point. The results reveal fast electronic and localized structural changes that lead to the ejection of particulates and the formation of micron-deep craters, reflecting the very nature of the strong repulsive forces at play

Perturbation of the circadian clock and pathogenesis of NAFLD.

The National Institute of Health (NCI R21 CA209940 and NIDDK R01CA233794 to T.F.B.), the Agence Nationale de Recherches sur le Sida et les Hépatites Virales (ANRS, 2015/1099), the Fondation ARC pour la Recherche sur le Cancer (IHU 201901299), the Institut Universitaire de France (IUF to T.F.B), and USIAS of the University of Strasbourg (A.M.). EU-InfectEra HepBccc (T.F.B.)All living organisms including humans, experience changes in the light exposure generated by the Earth's rotation. In anticipation of this unavoidable geo-physical variability, and to generate an appropriate biochemical response, species of many phyla, including mammals have evolved a nearly 24-hour endogenous timing device known as the circadian clock (CC), which is self-sustained, cell autonomous and is present in every cell type. At the heart of the 'clock' functioning resides the CC-oscillator, an elegantly designed transcriptional-translational feedback system. Notably, the core components of the CC-oscillator not only drive daily rhythmicity of their own synthesis, but also generate circadian phase-specific variability in the expression levels of thousands of target genes through transcriptional, post-transcriptional and post-translational mechanisms. Thereby, this 'clock'-system provides proper chronological coordination in the functioning of cells, tissues and organs. The CC governs many physiologically critical functions. Among these functions, the key role of the CC in maintaining metabolic homeostasis deserves special emphasis. Indeed, the several features of the modern lifestyle (e.g. travel-induced jet lag, rotating shift work, energy-dense food) which, force disruption of circadian rhythms have recently emerged as a major driver to global health problems like obesity, cardiovascular disease and metabolic liver disease such as non-alcoholic fatty liver disease (NAFLD). Here we review, the CC-dependent pathways in different tissues which play critical roles in mediating several critical metabolic functions under physiological conditions and discuss their impact for the development of metabolic disease with a focus on the liver

West Nile virus in Tunisia, 2014: First isolation from mosquitoes

International audienceSeveral outbreaks of human West Nile virus (WNV) infections were reported in Tunisia during the last two decades. Serological studies on humans as well as on equine showed intensive circulation of WNV in Tunisia. However, no virus screening of mosquitoes for WNV has been performed in Tunisia. In the present study, we collected mosquito samples from Central Tunisia to be examined for the presence of flaviviruses. A total of 102 Culex pipiens mosquitoes were collected in September 2014 from Central Tunisia. Mosquitoes were pooled according to the collection site, date and sex with a maximum of 5 specimens per pool and tested for the presence of flaviviruses by conventional reverse transcription heminested PCR and by a specific West Nile virus real time reverse transcription PCR. Of a total of 21 pools tested, 7 were positive for WNV and no other flavivirus could be evidenced in mosquito pools. In addition, WNV was isolated on Vero cells. Phylogenetic analysis showed that recent Tunisian WNV strains belong to lineage 1 WNV and are closely related to the Tunisian strain 1997 (PAH 001). This is the first detection and isolation of WNV from mosquitoes in Tunisia. Some areas of Tunisia are at high risk for human WNV infections. WNV is likely to cause future sporadic and foreseeable outbreaks. Therefore, it is of major epidemiological importance to set up an entomological surveillance as an early alert system. Timely detection of WNV should prompt vector control to prevent future outbreaks. In addition, education of people to protect themselves from mosquito bites is of major epidemiological importance as preventive measure against WNV infection

P-type semiconductor surfactant modified zinc oxide nanorods for hybrid bulk heterojunction solar cells

In this work, hybrid bulk heterojunction solar cells based on surfactant-modified zinc oxide nanorods (ZnO NRs) blended with poly-(3-hexylthiophene) (P3HT) are presented. (E)-2-cyano-3-(5′-(4-(dibutylamino)styryl)-2,2′-bithiophen-5-yl)acrylic acid (1), a p-type semiconductor, is used as grafted interfacial surfactant on ZnO NRs, named 1-ZnO NRs, in order to improve simultaneously the nanoscale morphology of the hybrid polymer blend as well as the electronic properties of the heterojunction interface. Our studies reveal that the ligand modification of ZnO NRs leads to strongly improved aggregate free P3HT/ZnO blends that show five time increased power conversion efficiency and corresponding photo-generated charge carrier transport compared to untreated ZnO NRs. From transient absorption spectroscopy, it was found that recombination kinetics were similar in the device using untreated ZnO and modified 1-ZnO NRs, respectively, pointing to a major impact of the ligand in the improvement of the blend morphology. Corresponding device optimization led to improvements of FF and Voc to values comparable to P3HT blends using fullerene acceptors, but photocurrent density of the P3HT/1-ZnO solar cells was found low even after optimization. The latter could be addressed to destruction of long range organization of P3HT induced by the presence of the ZnO NRs as well as low electron transport inside the blend