Administration of recombinant human IL-7 to mice alters the composition of B-lineage cells and T cell subsets, enhances T cell function, and induces regression of established metastases

These studies investigate the effects of exogenously administered recombinant human IL-7 (rhIL-7) on mouse leukocyte subsets in vivo in normal and tumor-bearing mice. The administration of rhIL-7 to normal mice caused a pronounced leukocytosis (three- to fivefold increase over background) in the spleen and lymph nodes, with B-lineage and T cells, NK cells, and macrophages all being increased. CD8+ T cells increased disproportionately, such that the CD4 to CD8 ratio decreased dramatically. The rhIL-7-induced effects were dose-dependent, increased with duration of treatment, and were reversible after cessation of rhIL-7 administration. T cell number increases after rhIL-7 treatment were primarily a result of an expansion of the peripheral T cell population. Importantly, splenocytes from rhIL-7-treated mice have enhanced proliferative responses to various T cell stimuli in vitro and were able to potentiate an allogeneic CTL response in vivo. The rhIL-7-induced changes in T cell number and the CD4 to CD8 ratio also were observed in mice bearing early Renca renal adenocarcinoma pulmonary metastases, and these changes coincided with up to a 75% reduction in pulmonary metastases. Overall, these results demonstrate that the administration of rhIL-7 to mice profoundly increases the number of B and T cells, and reduces the number of pulmonary metastases. The results also suggest that IL-7 may be useful for restoring lymphoid subsets in immunosuppressed hosts and in enhancing T cell-mediated immune responses. Such effects may be useful in the treatment of microbial diseases and cancer.     

Nondispersive delay line at microwave frequency by magnetostatic forward volume waves

The letter describes how a magnetostatic constant delay line can be designed and practically realised by using two identical dispersive delay lines operating with forward volume waves and frequency-inverting one of the band responses.     

A remote scanning Raman spectrometer for in situ measurements of works of art

In conservation science, one of the main concerns is to extract information from an artistic surface without damaging it. Raman spectroscopy has emerged in recent years as a reliable tool for the non-destructive analysis of a wide range of inorganic and organic materials in works of art and archaeological objects. Nevertheless, the technique is still mainly limited to the analysis of micro-samples taken from artistic surfaces. The development of an instrument able to perform non-contact analysis of an area of a few square centimeters aims to further increase the employment of this technique. This paper describes the development of a prototype Raman scanning spectrometer based on a diode laser, a 2D scanning mirror stage and a custom optical system, which can map a surface of 6 cm in diameter at a working distance of 20 cm. The device exhibits collecting optics with a depth of field close to 6 cm, which makes the Raman system suitable for the analysis of non-flat surfaces and three-dimensional objects. In addition, the overall dimensions and weight of the instrument have been limited in order to make the device transportable and, in principle, usable for in situ measurements. Details on the design of the device, with particular emphasis on the collecting optical system, and on results of the characterization tests carried out to assess its performances are reported. Finally, an example of an application involving the identification of pigments from a model painting is presented.     

The 2D wavelet transform on emerging architectures: GPUs and multicores

Because of the computational power of today??s GPUs, they are starting to be harnessed more and more to help out CPUs on high-performance computing. In addition, an increasing number of today??s state-of-the-art supercomputers include commodity GPUs to bring us unprecedented levels of performance in terms of raw GFLOPS and GFLOPS/cost. In this work, we present a GPU implementation of an image processing application of growing popularity: The 2D fast wavelet transform (2D-FWT). Based on a pair of Quadrature Mirror Filters, a complete set of application-specific optimizations are developed from a CUDA perspective to achieve outstanding factor gains over a highly optimized version of 2D-FWT run in the CPU. An alternative approach based on the Lifting Scheme is also described in Franco et al. (Acceleration of the 2D wavelet transform for CUDA-enabled Devices, 2010). Then, we investigate hardware improvements like multicores on the CPU side, and exploit them at thread-level parallelism using the OpenMP API and pthreads . Overall, the GPU exhibits better scalability and parallel performance on large-scale images to become a solid alternative for computing the 2D-FWT versus those thread-level methods run on emerging multicore architectures.     

Taxonomy of trust relationships in authorization domains for cloud computing

Cloud computing is revealing a new scenario where different cloud customers need to collaborate to meet client demands. The cloud stack must be able to support this situation by enabling collaborative agreements between cloud customers. However, these collaborations entail new security risks since participating entities should trust each other to share a set of resources. The management of trust relationships in the cloud is gaining importance as a key element to establish a secure environment where entities are given full control in the definition of which particular services or resources they are willing to share. Entities can cooperate at different levels of trust, according to their willingness of sharing information. This paper analyses these collaboration agreements defining a taxonomy of different levels of trust relationships among customers for the cloud. Privacy concerns, assumed risk, as well as easiness in the definition of the trust relationships have been taken into account. A set of different trust relationships have been identified and modeled, enabling entities to control the information they share with others in the cloud. The proposed model has been validated with a prototypical implementation. Likewise, some examples to illustrate the application of these trust models to common cloud collaboration scenarios are provided.     

Influence of CYP1A2 and NAT2 Metabolic Phenotypes on Smokers' Urinary Mutagenicity

The influence of the metabolic phenotypes NAT2 and CYP1A2 on urinary mutagenicity of 118 smokers was studied. Mutagenicity of urine samples was determined by Ames test (preincubation plate incorporation assay on YG1024 Salmonella typhimurium strain with S9 mix). Urinary nicotine plus its metabolites were determined to check cigarette smoke intake. The N -acetyltransferase (NAT2) and cytochrome P450 1A2 (CYP1A2) phenotypes were measured by the molar ratio of urinary caffeine metabolites, determined by HPLC analysis. Urinary mutagenicity was significantly higher in smokers CYP1A2 extensive (EM) than in CYP1A2 poor metabolizers (PM) (Mann-Whitney U test, p = 0.020). Linear multiple regression analysis shows that an increase in urinary mutagenicity levels was significantly related to cigarette smoke intake and to CYP1A2 N -hydroxylation activity ( t = 5.06, p < 0.001, and t = 2.33, p = 0.021), but not to NAT2 acetylation phenotype. In conclusion, phenotypic differences in metabolic activation of tobacco smoke mutagens are able to modulate the presence of mutagens in urine of cigarette smokers and, consequently, the potential genotoxic risk.     

Ischemic and Ozone Oxidative Preconditioning in the Protection Against Hepatic Ischemic-Reperfusion Injury

It has been demonstrated that ozone, probably through a mechanism of oxidative preconditioning (OP), protected the liver against the damage mediated by reactive oxygen species. Taking into account that iscehmic preconditioning (IschP) is also a protective mechanism, a comparative study between both preconditioning settings was performed in order to study the effectiveness of both protective procedures. Rats were randomly divided into 4 groups: 1- control, sham operated (anesthesia and laparotomy plus surgical manipulation); 2- I/R (ischemia for 90?min followed by 90?min reperfusion); 3- Ischp+I/R, as group 2 but submitted to a previous ischemic preconditioning (ischemia 10?min and reperfusion 10?min); 4- OzoneOP+I/R, as group 2 but submitted to a pervious oxidative preconditioning with 15 sessions, daily, of ozone by rectal administration (dose of 1?mg/kg). The comparison between both preconditionings showed no biochemical differences for the parameters evaluated. Nevertheless, the histological study demonstrated that the protective effect produced by the OzoneOP is superior to that achieved with the IschP.     

Hot‐wire parallel technique: A new method for simultaneous determination of thermal properties of polymers

The hot‐wire parallel technique standardized for determining the thermal conductivity of ceramic materials was employed in the determination of the thermal properties of polymers. For these materials, additional care must be taken considering the low melting point of polymers, when compared with that for ceramic materials. Samples can be prepared either in the shape of bricks or in the shape of half‐cylinders. The thermal conductivity and the specific heat were simultaneously determined from the same experimental thermal transient, and the thermal diffusivity is derived from these properties. Five different polymers with different structures at room temperature were selected, and measurements were carried out from room temperature to approximately the maximum service operating temperature. A nonlinear least‐squares fitting method was employed in the calculations, so that all the experimental points obtained are considered in the thermal properties' calculations. The apparatus used in this work is fully automatic. The reproducibility is very good with respect to the thermal conductivity, even with a defective experimental arrangement with respect to the theoretical model. However, deviations from the theoretical model have a severe influence on the specific heat values and, consequently, on the thermal diffusivity. Experimental results were compared with those available in the literature, showing the applicability of this technique for the determination of thermal properties of polymers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1779–1786, 2002