74 research outputs found
Assessment of the performance of asphalt rubber layers on noise abatement
Layers with a very high content of rubber have shown to be very effective on noise abatement
despite their reduced durability. On the contrary, layers with a rubberized asphalt binder have shown
to be durable, but their performance regarding noise abatement is not consensual yet. This paper aims
at assessing the effect of the use of layers with rubberized asphalt binder on noise abatement. For this
purpose seven road sections with different surface types, among which five gap graded and three with
rubberized asphalt have been selected. In these road sections the tyre-road noise generated by a heavy
truck and two light vehicles at three levels of speed were measured by means of pass-by tests. Surface
texture tests were also performed. The results focused on the noise level variation versus speed, the
average noise level for each speed level versus type of surface and the average noise level variation
with regards to a reference surface. Mixtures with rubberized asphalt did not show a significantly
better performance. In fact, the same performance may be achieved with other type of gap graded thin
mixtures. The results obtained might be better explained if other parameters than the rubberized
asphalt binder are taken into account. Further research on the effect of porosity and texture on noise
generation is being done. It is intended to perform absorption tests in all the surfaces analysed in order
to study this issue in depth and fully understand the effect of the rubber on noise generation
Skewed Differentiation of Circulating Vγ9Vδ2 T Lymphocytes in Melanoma and Impact on Clinical Outcome
Objective
The aim of this study was to evaluate over time circulating γδ T lymphocytes in melanoma
patients in terms of frequency, effector functions, and relationship with clinical stage and
evolution, by comparing preoperative values to those obtained at a mean follow-up of 36
months or in the event of recurrence or disease progression, and to those of healthy controls.
Also, we correlated the presence of tumor-infiltrating γδ T lymphocytes with clinical
evolution of melanoma.
Results
Mean frequencies of circulating γδ T cells before and after melanoma removal were very
similar and comparable to healthy subjects, but patients who progressed to stage III or IV
showed a significantly decreased frequency of circulating Vγ9Vδ2 T cells. The distribution
of Vγ9Vδ2 memory and effector subsets was similar in healthy subjects and melanoma
patients at diagnosis, but circulating γδ T cells of patients after melanoma removal had a
skewed terminally-differentiated effector memory phenotype. Highly suggestive of progressive
differentiation toward a cytotoxic phenotype, Vγ9Vδ2T cells from patients at follow up
had increased cytotoxic potential and limited cytokine production capability, while the opposite
pattern was detected in Vγ9Vδ2T cells from patients before melanoma removal.
Conclusions
Follow-up data also showed that tumor infiltrating γδ T cells were significantly associated
with lower mortality and relapse rates, suggesting that they may serve as a prognostic biomarker,
for human melanom
Silent surfaces : an experience in Portugal
It is acknowledged that traffic noise affects human behaviour and health. Measures aiming
at mitigating the impact of traffic noise are not always viable in urban areas. In Portugal,
road designers have recently started to consider silent surfaces as alternative within their
road pavement projects.
In this paper the tire-surface noise of three surface layers integrated in a rehabilitation
project carried out in an urban road that carries more than 40000 vehicles per day is
assessed: i) one dense asphalt layer with limited maximum aggregate size, following the
SILVIA recommendations for low noise surfaces; ii) two very-thin surfaces with different
grading, which are an adaptation of the very-thin layers widely used in France to
Portuguese conditions.
The surface layers were constructed consecutively, involving segment lengths with more
than 500 m. The surface texture was measured using a high speed profilometer. Skid
resistance was also measured. The noise level was measured both by pass-by tests with
selected traffic (trucks and light vehicles) at several speeds and by close proximity tests.
The thin layers tested provided very good noise reduction values, especially at high
speeds, and had a better performance than gap graded asphalt rubber surfaces frequently
used in Portugal
A unique population of effector memory lymphocytes identified by CD146 having a distinct immunophenotypic and genomic profile
<p>Abstract</p> <p>Background</p> <p>CD146 is a well described homotypic adhesion molecule found on endothelial cells and a limited number of other cell types. In cells from the peripheral circulation, CD146 has also been reported to be on activated lymphocytes <it>in vitro </it>and <it>in vivo</it>. The function associated with CD146 expression on lymphoid cells is unknown and very little information is available concerning the nature of CD146+ lymphocytes. In the current study, lymphocytes from healthy donors were characterized based upon the presence or absence of CD146 expression.</p> <p>Results</p> <p>CD146 was expressed on a low percentage of circulating T lymphocytes, B lymphocytes, and NK cells in healthy individuals. CD146 expression can be induced and upregulated <it>in vitro </it>on both B cells and T cells, but does not correlate with the expression of other markers of T cell activation. CD146 positive T cells do not represent clonal expansions as determined with the use of anti Vβ reagents. Data suggest that CD146 positive cells have enhanced adherence to endothelial monolayers in vitro. Gene profiling and immunophenotyping studies between CD146+ and CD146- T cells revealed several striking genotypic distinctions such as the upregulation of IL-8 and phenotypic differences including the paucity of CCR7 and CD45RA among CD146 positive T cells, consistent with effector memory function. A number of genes involved in cell adhesion, signal transduction, and cell communication are dramatically upregulated in CD146+ T cells compared to CD146- T cells.</p> <p>Conclusion</p> <p>CD146 appears to identify small, unique populations of T as well as B lymphocytes in the circulation. The T cells have immunophenotypic characteristics of effector memory lymphocytes. The characteristics of these CD146+ lymphocytes in the circulation, together with the known functions in cell adhesion of CD146 on endothelial cells, suggests that these lymphocytes may represent a small subpopulation of cells primed to adhere to the endothelium and possibly extravasate to sites of inflammation.</p
Up-regulation of METCAM/MUC18 promotes motility, invasion, and tumorigenesis of human breast cancer cells
<p>Abstract</p> <p>Background</p> <p>Conflicting research has identified METCAM/MUC18, an integral membrane cell adhesion molecule (CAM) in the Ig-like gene super-family, as both a tumor promoter and a tumor suppressor in the development of breast cancer. To resolve this, we have re-investigated the role of this CAM in the progression of human breast cancer cells.</p> <p>Methods</p> <p>Three breast cancer cell lines were used for the tests: one luminal-like breast cancer cell line, MCF7, which did not express any METCAM/MUC18, and two basal-like breast cancer cell lines, MDA-MB-231 and MDA-MB-468, which expressed moderate levels of the protein.</p> <p>MCF7 cells were transfected with the human METCAM/MUC18 cDNA to obtain G418-resistant clones which expressed the protein and were used for testing effects of human METCAM/MUC18 expression on <it>in vitro </it>motility and invasiveness, and <it>in vitro </it>and <it>in vivo </it>tumorigenesis. Both MDA-MB-231 and MDA-MB-468 cells already expressed METCAM/MUC18. They were directly used for <it>in vitro </it>tests in the presence and absence of an anti-METCAM/MUC18 antibody.</p> <p>Results</p> <p>In MCF7 cells, enforced METCAM/MUC18 expression increased <it>in vitro </it>motility, invasiveness, anchorage-independent colony formation (<it>in vitro </it>tumorigenesis), and <it>in vivo </it>tumorigenesis. In both MDA-MB-231 and MDA-MB-468 cells, the anti-METCAM/MUC18 antibody inhibited both motility and invasiveness. Though both MDA-MB-231 and MDA-MB-468 cells established a disorganized growth in 3D basement membrane culture assay, the introduction of the anti-METCAM/MUC18 antibody completely destroyed their growth in the 3D culture.</p> <p>Conclusion</p> <p>These findings support the notion that human METCAM/MUC18 expression promotes the progression of human breast cancer cells by increasing their motility, invasiveness and tumorigenesis.</p
Perivascular-like cells contribute to the stability of the vascular network of osteogenic tissue formed from cell sheet-based constructs
In recent years several studies have been supporting the existence of a close relationship in terms of function and progeny
between Mesenchymal Stem Cells (MSCs) and Pericytes. This concept has opened new perspectives for the application of
MSCs in Tissue Engineering (TE), with special interest for the pre-vascularization of cell dense constructs. In this work, cell
sheet technology was used to create a scaffold-free construct composed of osteogenic, endothelial and perivascular-like
(CD146+) cells for improved in vivo vessel formation, maturation and stability. The CD146 pericyte-associated phenotype
was induced from human bone marrow mesenchymal stem cells (hBMSCs) by the supplementation of standard culture
medium with TGF-b1. Co-cultured cell sheets were obtained by culturing perivascular-like (CD146+) cells and human
umbilical vein endothelial cells (HUVECs) on an hBMSCs monolayer maintained in osteogenic medium for 7 days. The
perivascular-like (CD146+) cells and the HUVECs migrated and organized over the collagen-rich osteogenic cell sheet,
suggesting the existence of cross-talk involving the co-cultured cell types. Furthermore the presence of that particular ECM
produced by the osteoblastic cells was shown to be the key regulator for the singular observed organization. The
osteogenic and angiogenic character of the proposed constructs was assessed in vivo. Immunohistochemistry analysis of
the explants revealed the integration of HUVECs with the host vasculature as well as the osteogenic potential of the created
construct, by the expression of osteocalcin. Additionally, the analysis of the diameter of human CD146 positive blood
vessels showed a higher mean vessel diameter for the co-cultured cell sheet condition, reinforcing the advantage of the
proposed model regarding blood vessels maturation and stability and for the in vitro pre-vascularization of TE constructs.Funding provided by Fundacao para a Ciencia e a Tecnologia project Skingineering (PTDC/SAU-OSM/099422/2008). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
"Dangerous to Themselves and Others, and of Public Scandal": The Internment Procedure
Abstract
Through G.'s admission and medical files, this chapter illustrates internment laws and procedures, highlighting how Fascism pushed pre-existing legislation to its extreme consequences. In reconstructing internment's bureaucratic and legal practices, the chapter emphasises how the law could be bent to accommodate the regime's need to isolate those perceived as "different" and how psychiatry acquiesced in offering to "correct" individuals considered "non-conforming", "amoral", "immoral", "deviant", rebellious and, among them, homosexuals, in exchange for an increase of power and status
- …