Adiponectin Expression from Human Adipose Tissue: Relation to Obesity, Insulin Resistance, and Tumor Necrosis Factor-α Expression

Adiponectin is a 29-kDa adipocyte protein that has been linked to the insulin resistance of obesity and lipodystrophy. To better understand the regulation of adiponectin expression, we measured plasma adiponectin and adipose tissue adiponectin mRNA levels in nondiabetic subjects with varying degrees of obesity and insulin resistance. Plasma adiponectin and adiponectin mRNA levels were highly correlated with each other (r = 0.80, P \u3c 0.001), and obese subjects expressed significantly lower levels of adiponectin. However, a significant sex difference in adiponectin expression was observed, especially in relatively lean subjects. When men and women with a BMI2were compared, women had a twofold higher percent body fat, yet their plasma adiponectin levels were 65% higher (8.6 ± 1.1 and 14.2 ± 1.6 μg/ml in men and women, respectively; P \u3c 0.02). Plasma adiponectin had a strong association with insulin sensitivity index (SI) (r = 0.67, P \u3c 0.0001, n = 51) that was not affected by sex, but no relation with insulin secretion. To separate the effects of obesity (BMI) from SI, subjects who were discordant for SI were matched for BMI, age, and sex. Using this approach, insulin-sensitive subjects demonstrated a twofold higher plasma level of adiponectin (5.6 ± 0.6 and 11.2 ± 1.1 μg/ml in insulin-resistant and insulin-sensitive subjects, respectively; P \u3c 0.0005). Adiponectin expression was not related to plasma levels of leptin or interleukin-6. However, there was a significant inverse correlation between plasma adiponectin and tumor necrosis factor (TNF)-α mRNA expression (r = -0.47, P \u3c 0.005), and subjects with the highest levels of adiponectin mRNA expression secreted the lowest levels of TNF-α from their adipose tissue in vitro. Thus, adiponectin expression from adipose tissue is higher in lean subjects and women, and is associated with higher degrees of insulin sensitivity and lower TNF-α expression

Integrated optics for astronomical interferometry - VI. Coupling the light of the VLTI in K band

Our objective is to prove that integrated optics (IO) is not only a good concept for astronomical interferometry but also a working technique with high performance. We used the commissioning data obtained with the dedicated K-band integrated optics two-telescope beam combiner which now replaces the fiber coupler MONA in the VLTI/VINCI instrument. We characterize the behaviour of this IO device and compare its properties to other single mode beam combiner like the previously used MONA fiber coupler. The IO combiner provides a high optical throughput, a contrast of 89% with a night-to-night stability of a few percent. Even if a dispersive phase is present, we show that it does not bias the measured Fourier visibility estimate. An upper limit of 0.005 for the cross-talk between linear polarization states has been measured. We take advantage of the intrinsic contrast stability to test a new astronomical prodecure for calibrating diameters of simple stars by simultaneously fitting the instrumental contrast and the apparent stellar diameters. This method reaches an accuracy with diameter errors of the order of previous ones but without the need of an already known calibrator. These results are an important step of integrated optics and paves the road to incoming imaging interferometer projects

Gigantism in unique biogenic magnetite at the Paleocene-Eocene Thermal Maximum

We report the discovery of exceptionally large biogenic magnetite crystals in clay-rich sediments spanning the Paleocene-Eocene Thermal Maximum (PETM) in a borehole at Ancora, New Jersey. Aside from previously-described abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite up to 4 μm long and hexaoctahedral prisms up to 1.4 μm long. Similar to magnetite produced by magnetotactic bacteria, these single-crystal particles exhibit chemical composition, lattice perfection, and oxygen isotopes consistent with an aquatic origin. Electron holography indicates single-domain magnetization despite their large crystal size. We suggest that the development of a thick suboxic zone with high iron bioavailability – a product of dramatic changes in weathering and sedimentation patterns driven by severe global warming – drove diversification of magnetite-forming organisms, likely including eukaryotes

5GEx: realising a Europe-wide multi-domain framework for software-defined infrastructures

Market fragmentation has resulted in a multitude of network and cloud/data center operators, each focused on different countries, regions and technologies. This makes it difficult and costly to create infrastructure services spanning multiple domains, such as virtual connectivity or compute resources. In this article, we discuss the goals and work being done within the 5GEx (5G Exchange) project in realising a Europe-wide multi-domain platform. This platform aims at enabling cross-domain orchestration of services over multiple administrations or over multi-domain single administrations in the context of emerging 5G networking. The 5GEx vision is based on introducing a unification via network function virtualisation/software-defined networking compatible multi-domain orchestration for networks, clouds and services. We describe the motivation and 5GEx vision, the adopted architecture and the next steps in terms of implementation and experimentation.This work is performed in the framework of the H2020-ICT-2014 project 5GEx (Grant Agreement no. 671636), which is partially funded by the European Commission

Data reduction methods for single-mode optical interferometry - Application to the VLTI two-telescopes beam combiner VINCI

The interferometric data processing methods that we describe in this paper use a number of innovative techniques. In particular, the implementation of the wavelet transform allows us to obtain a good immunity of the fringe processing to false detections and large amplitude perturbations by the atmospheric piston effect, through a careful, automated selection of the interferograms. To demonstrate the data reduction procedure, we describe the processing and calibration of a sample of stellar data from the VINCI beam combiner. Starting from the raw data, we derive the angular diameter of the dwarf star Alpha Cen A. Although these methods have been developed specifically for VINCI, they are easily applicable to other single-mode beam combiners, and to spectrally dispersed fringes.Comment: Accepted for publication in Astronomy & Astrophysics, 17 pages, 19 figure

Searching for faint companions with VLTI/PIONIER. I. Method and first results

Context. A new four-telescope interferometric instrument called PIONIER has recently been installed at VLTI. It provides improved imaging capabilities together with high precision. Aims. We search for low-mass companions around a few bright stars using different strategies, and determine the dynamic range currently reachable with PIONIER. Methods. Our method is based on the closure phase, which is the most robust interferometric quantity when searching for faint companions. We computed the chi^2 goodness of fit for a series of binary star models at different positions and with various flux ratios. The resulting chi^2 cube was used to identify the best-fit binary model and evaluate its significance, or to determine upper limits on the companion flux in case of non detections. Results. No companion is found around Fomalhaut, tau Cet and Regulus. The median upper limits at 3 sigma on the companion flux ratio are respectively of 2.3e-3 (in 4 h), 3.5e-3 (in 3 h) and 5.4e-3 (in 1.5 h) on the search region extending from 5 to 100 mas. Our observations confirm that the previously detected near-infrared excess emissions around Fomalhaut and tau Cet are not related to a low-mass companion, and instead come from an extended source such as an exozodiacal disk. In the case of del Aqr, in 30 min of observation, we obtain the first direct detection of a previously known companion, at an angular distance of about 40 mas and with a flux ratio of 2.05e-2 \pm 0.16e-2. Due to the limited u,v plane coverage, its position can, however, not be unambiguously determined. Conclusions. After only a few months of operation, PIONIER has already achieved one of the best dynamic ranges world-wide for multi-aperture interferometers. A dynamic range up to about 1:500 is demonstrated, but significant improvements are still required to reach the ultimate goal of directly detecting hot giant extrasolar planets.Comment: 11 pages, 6 figures, accepted for publication in A&

Intracerebral delivery of 5-iodo-2'-deoxyuridine in combination with synchrotron stereotactic radiation for the therapy of the F98 glioma.

International audienceIodine-enhanced synchrotron stereotactic radiotherapy takes advantage of the radiation dose-enhancement produced by high-Z elements when irradiated with mono-energetic beams of synchrotron X-rays. In this study it has been investigated whether therapeutic efficacy could be improved using a thymidine analogue, 5-iodo-2'-deoxyuridine (IUdR), as a radiosentizing agent. IUdR was administered intracerebrally over six days to F98 glioma-bearing rats using Alzet osmotic pumps, beginning seven days after tumor implantation. On the 14th day, a single 15 Gy dose of 50 keV synchrotron X-rays was delivered to the brain. Animals were followed until the time of death and the primary endpoints of this study were the mean and median survival times. The median survival times for irradiation alone, chemotherapy alone or their combination were 44, 32 and 46 days, respectively, compared with 24 days for untreated controls. Each treatment alone significantly increased the rats' survival in comparison with the untreated group. Their combination did not, however, significantly improve survival compared with that of X-irradiation alone or chemotherapy alone. Further studies are required to understand why the combination of chemoradiotherapy was no more effective than X-irradiation alone

Bethe-Salpeter Amplitudes and Static Properties of the Deuteron

Extended calculations of the deuteron's static properties, based on the numerical solution of the Bethe-Salpeter equation, are presented. A formalism is developed, which provides a comparative analysis of the covariant amplitudes in various representations and nonrelativistic wave functions. The magnetic and quadrupole moments of the deuteron are calculated in the Bethe-Salpeter formalism and the role of relativistic corrections is discussed.Comment: 33 pages ([aps]{revtex} style), 9 Postscript figures; (55 pages if [preprint,aps]{revtex} style is used