1,518 research outputs found
Evaluation et prise en charge de l’envahissement mandibulaire dans les carcinomes epidermoïdes de la cavite orale et de l’oropharynx
Objectif : Le but de notre étude est l’évaluation de l’atteinte mandibulaire dans les carcinomes épidermoïdes de la cavité orale et de l’oropharynx. Matériel et méthodes : Il s’agit d’une étude rétrospective à propos de 34 patients colligés sur 6 ans (1999-2004) et ayant un carcinome épidermoïde de la cavité orale et/ou de l’oropharynx avec envahissement mandibulaire confirmé à l’anatomopathologie. L’atteinte mandibulaire a été évaluée par l’examen clinique, l’orthopantomographie, la tomodensitométrie, et par les constatations peropératoires du chirurgien. Tous les patients ont eu un évidement ganglionnaire, une exérèse tumorale associée à une mandibulectomie segmentaire interruptrice ou conservatrice. Résultats : L’envahissement mandibulaire a été suspecté cliniquement chez 70,5% des patients devant l’adhérence de la tumeur à l’os. Après examen clinique et imagerie, cette atteinte a été diagnostiquée chez 88,2% des patients. Dans 11,8% des cas, l’atteinte n’a été suspectée qu’en peropératoire. L’examen histologique a confirmé l’atteinte osseuse chez tous les patients. La mandibulectomie segmentaire a été pratiquée chez 17 patients devant l’atteinte du canal mandibulaire. Vingt-huit patients ont eu une radiothérapie postopératoire à la dose moyenne de 64 Gy. Les taux de récidive, de métastase et de décès étaient respectivement de 11,7%, 17,6% et 17,6% pour les patients qui ont eu une mandibulectomie segmentaire, et de 23,5%, 17,6% et 23,5% pour ceux qui ont eu une mandibulectomie conservatrice. Par ailleurs, 76,5% et 29,5% des patients ayant eu respectivement une mandibulectomie segmentaire et une mandibulectomie conservatrice avaient une gêne fonctionnelle importante lors de l’alimentation. Conclusion : L’examen clinique, l’imagerie et l’examen peropératoire sont d’un apport capital dans l’évaluation de l’atteinte mandibulaire. Une atteinte épargnant le canal mandibulaire justifie une mandibulectomie conservatrice permettant d’avoir de meilleurs résultats esthétiques et fonctionnels tout en assurant un contrôle carcinologiquement satisfaisant.Mots clés : envahissement mandibulaire, carcinome épidermoïde, cavité orale, oropharynx, mandibulectomie segmentaire, mandibulectomie conservatric
Tumor suppression in mice lacking GABARAP, an Atg8/LC3 family member implicated in autophagy, is associated with alterations in cytokine secretion and cell death
GABARAP belongs to an evolutionary highly conserved gene family that has a
fundamental role in autophagy. There is ample evidence for a crosstalk between
autophagy and apoptosis as well as the immune response. However, the molecular
details for these interactions are not fully characterized. Here, we report
that the ablation of murine GABARAP, a member of the Atg8/LC3 family that is
central to autophagosome formation, suppresses the incidence of tumor
formation mediated by the carcinogen DMBA and results in an enhancement of the
immune response through increased secretion of IL-1β, IL-6, IL-2 and IFN-γ
from stimulated macrophages and lymphocytes. In contrast, TGF-β1 was
significantly reduced in the serum of these knockout mice. Further, DMBA
treatment of these GABARAP knockout mice reduced the cellularity of the spleen
and the growth of mammary glands through the induction of apoptosis. Gene
expression profiling of mammary glands revealed significantly elevated levels
of Xaf1, an apoptotic inducer and tumor-suppressor gene, in knockout mice.
Furthermore, DMBA treatment triggered the upregulation of pro-apoptotic (Bid,
Apaf1, Bax), cell death (Tnfrsf10b, Ripk1) and cell cycle inhibitor (Cdkn1a,
Cdkn2c) genes in the mammary glands. Finally, tumor growth of B16 melanoma
cells after subcutaneous inoculation was inhibited in GABARAP-deficient mice.
Together, these data provide strong evidence for the involvement of GABARAP in
tumorigenesis in vivo by delaying cell death and its associated immune-related
response
Evapotranspiration and evaporation/transpiration partitioning with dual source energy balance models in agricultural lands
EvapoTranspiration (ET) is an important component of the water cycle,
especially in semi-arid lands. Its quantification is crucial for a
sustainable management of scarce water resources. A way to quantify ET is to
exploit the available surface temperature data from remote sensing as a
signature of the surface energy balance, including the latent heat flux.
Remotely sensed energy balance models enable to estimate stress levels and,
in turn, the water status of most continental surfaces. The evaporation and
transpiration components of ET are also just as important in agricultural
water management and ecosystem health monitoring. Single temperatures can be
used with dual source energy balance models but rely on specific assumptions
on raw levels of plant water stress to get both components out of a single
source of information. Additional information from remote sensing data are
thus required, either something specifically related to evaporation (such as
surface water content) or transpiration (such as PRI or fluorescence). This
works evaluates the SPARSE dual source energy balance model ability to
compute not only total ET, but also water stress and
transpiration/evaporation components. First, the theoretical limits of the ET
component retrieval are assessed through a simulation experiment using both
retrieval and prescribed modes of SPARSE with the sole surface temperature. A
similar work is performed with an additional constraint, the topsoil surface
soil moisture level, showing the significant improvement on the retrieval.
Then, a flux dataset acquired over rainfed wheat is used to check the
robustness of both stress levels and ET retrievals. In particular, retrieval
of the evaporation and transpiration components is assessed in both
conditions (forcing by the sole temperature or the combination of temperature
and soil moisture). In our example, there is no significant difference in the
performance of the total ET retrieval, since the evaporation rate retrieved
from the sole surface temperature is already fairly close to the one we can
reconstruct from observed surface soil moisture time series, but current work
is underway to test it over other plots.</p
Genetic analysis of lung function in inbred mice suggests vitamin D receptor as a candidate gene
Vitamin D receptor (VDR) polymorphisms are associated with an increased asthma incidence in human populations; however, observations in Vdr knockout mice are unclear. The aim of our study was to determine the influence of the genetic variation in Vdr among inbred strains on lung resistance (i.e., dynamic and airway resistance). In an intercross between the strains C57BL/6J (B6) and KK/HlJ (KK), we identified that a significant QTL for dynamic resistance on Chr X was interacting with a QTL on Chr 15. The Chr 15 QTL peak was located in close proximity to the Vdr locus. We further examined if phenotypes of several inbred strains with varying Vdr genotypes differed. Strains with a B6-like genotype on the Vdr locus had significantly lower airway resistance than strains with a KK-like genotype. Vdr knockout mice were examined for dynamic resistance and showed significantly higher resistance than mice with one (i.e., heterozygous) or both copies (i.e., wild-type) of the Vdr. In comparison to B6, the strain A/J is more resistant but carries the same genotype at the Vdr locus. Dietary vitamin D manipulation in the strain A/J did not rescue the high airway resistance phenotype. Finally, we observed that serum vitamin D does not correlate significantly with lung resistance parameters in a survey of 18 strains. Conclusively, Vdr contributes to the phenotypic variation of lung resistance in inbred mice but other molecules in the Vdr pathway and extended network [i.e., Chr X gene(s)] may contribute as well
Piezoelectric Property of Electrospun PVDF Nanofibers as Linking Tips of Artificial-Hair-Cell Structures in Cochlea
This is the final version. Available from MDPI via the DOI in this record. The death of hair cells and damage of natural tip links is one of the main causes of hearing-loss disability, and the development of an advanced artificial hearing aid holds the key to assisting those suffering from hearing loss. This study demonstrates the potential of using electrospun polyvinylidene fluoride (PVDF) fibers to serve as the artificial tip links, for long-term hearing-aid-device development based on their piezoelectric properties. We have shown that the electrospun PVDF-fiber web, consisting of fibers ranging from 30-220 nm in diameter with high β-phase content, possesses the high piezoresponse of 170 mV. Analyses based on combined characterization methods including SEM, TEM, XRD, FTIR, Raman, DSC, XPS, PFM and piezoelectricity have confirmed that an optimized value of 15 wt.% PVDF could act as an effective candidate for a tip-link connector in a vibration-frequency prototype. Based on this easily reproducible electrospinning technique and the multifunctionalities of the resulting PVDF fibers, this fundamental study may shed light on the bio-inspired design of artificial, self-powered, high performance, hair-cell-like sensors in cochlea to tackle the hearing loss issue.Engineering and Physical Sciences Research Council (EPSRC)Engineering and Physical Sciences Research Council (EPSRC
Study of Heparin in Intestinal Ischemia and Reperfusion in Rats: Morphologic and Functional Evaluation
To study whether treatment with heparin (HEP) attenuates intestinal dysfunction caused by ischemia (I) and reperfusion (R), rats were treated with HEP (100 U/kg intravenously) or saline solution (SS) before I (60 min), which was produced by occlusion of the superior mesenteric artery, and R (120 min). After I or I/R, we mounted 2-cm jejunal segment in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl, using a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Compared with the sham group, jejunal contractions were similar in the I + HEP and the I/R + HEP groups, but reduced in the I + SS and the I/R + SS groups. the jejunal enteric nerves were damaged in the I + SS and the I/R + SS, but not in the I + HEP and the I/R + HEP cohorts. These results suggested that HEP attenuated intestinal dysfunction caused by I and I/R.Universidade Federal de São Paulo, Escola Paulista Med, Dept Surg, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pharmacol, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biochem, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Morphol, BR-04023900 São Paulo, BrazilFed Univ Great Dourados, Sch Med, Dourados, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Surg, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pharmacol, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biochem, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Morphol, BR-04023900 São Paulo, BrazilWeb of Scienc
Can we identify non-stationary dynamics of trial-to-trial variability?"
Identifying sources of the apparent variability in non-stationary scenarios is a fundamental problem in many biological data analysis settings. For instance, neurophysiological responses to the same task often vary from each repetition of the same experiment (trial) to the next. The origin and functional role of this observed variability is one of the fundamental questions in neuroscience. The nature of such trial-to-trial dynamics however remains largely elusive to current data analysis approaches. A range of strategies have been proposed in modalities such as electro-encephalography but gaining a fundamental insight into latent sources of trial-to-trial variability in neural recordings is still a major challenge. In this paper, we present a proof-of-concept study to the analysis of trial-to-trial variability dynamics founded on non-autonomous dynamical systems. At this initial stage, we evaluate the capacity of a simple statistic based on the behaviour of trajectories in classification settings, the trajectory coherence, in order to identify trial-to-trial dynamics. First, we derive the conditions leading to observable changes in datasets generated by a compact dynamical system (the Duffing equation). This canonical system plays the role of a ubiquitous model of non-stationary supervised classification problems. Second, we estimate the coherence of class-trajectories in empirically reconstructed space of system states. We show how this analysis can discern variations attributable to non-autonomous deterministic processes from stochastic fluctuations. The analyses are benchmarked using simulated and two different real datasets which have been shown to exhibit attractor dynamics. As an illustrative example, we focused on the analysis of the rat's frontal cortex ensemble dynamics during a decision-making task. Results suggest that, in line with recent hypotheses, rather than internal noise, it is the deterministic trend which most likely underlies the observed trial-to-trial variability. Thus, the empirical tool developed within this study potentially allows us to infer the source of variability in in-vivo neural recordings
Particulate air pollution and chronic ischemic heart disease in the eastern United States: a county level ecological study using satellite aerosol data
<p>Abstract</p> <p>Background</p> <p>There are several known factors that cause ischemic heart disease. However, the part played by air pollution still remains something of a mystery. Recent attention has focused on the chronic effect of particulate matter on heart disease. Satellite-derived aerosol optical depth (AOD) was found to be correlated with <it>PM</it><sub>2.5 </sub>in the eastern US. The objective of this study was to examine if there is an association between aerosol air pollution as indicated by AOD and chronic ischemic heart disease (CIHD) in the eastern US.</p> <p>Methods</p> <p>An ecological geographic study method was employed. Race and age standardized mortality rate (SMR) of CIHD was computed for each of the 2306 counties for the time period 2003–2004. A mean AOD raster grid for the same period was derived from Moderate Resolution Imaging Spectrometer (MODIS) aerosol data and the average AOD was calculated for each county. A bivariate Moran's I scatter plot, a map of local indicator of spatial association (LISA) clusters, and three regression models (ordinary least square, spatial lag, and spatial error) were used to analyze the relationship between AOD and CIHD SMR.</p> <p>Results</p> <p>The global Moran's I value is 0.2673 (<it>p </it>= 0.001), indicating an overall positive spatial correlation of CIHD SMR and AOD. The entire study area is dominated by spatial clusters of AOD against SMR (high AOD and high SMR in the east, and low AOD and low SMR in the west) (permutations = 999, <it>p </it>= 0.05). Of the three regression models, the spatial error model achieved the best fit (R<sup>2 </sup>= 0.28). The effect of AOD is positive and significant (beta = 0.7774, p = 0.01).</p> <p>Conclusion</p> <p>Aerosol particle pollution has adverse effect on CIHD mortality risk in the eastern US. High risk of CIHD mortality was found in areas with elevated levels of outdoor aerosol air pollution as indicated by satellite derived AOD. The evidence of the association would support targeting of policy interventions on such areas to reduce air pollution levels. Remote sensing AOD data could be used as an alternative health-related indictor of air quality.</p
Inclusive Production Cross Sections from 920 GeV Fixed Target Proton-Nucleus Collisions
Inclusive differential cross sections and
for the production of \kzeros, \lambdazero, and
\antilambda particles are measured at HERA in proton-induced reactions on C,
Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to
GeV in the proton-nucleon system. The ratios of differential
cross sections \rklpa and \rllpa are measured to be and , respectively, for \xf . No significant dependence upon the
target material is observed. Within errors, the slopes of the transverse
momentum distributions also show no significant
dependence upon the target material. The dependence of the extrapolated total
cross sections on the atomic mass of the target material is
discussed, and the deduced cross sections per nucleon are
compared with results obtained at other energies.Comment: 17 pages, 7 figures, 5 table
Search for the glueball candidates f0(1500) and fJ(1710) in gamma gamma collisions
Data taken with the ALEPH detector at LEP1 have been used to search for gamma
gamma production of the glueball candidates f0(1500) and fJ(1710) via their
decay to pi+pi-. No signal is observed and upper limits to the product of gamma
gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have
been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) <
0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) < 0.55 keV
at 95% confidence level.Comment: 10 pages, 3 figure
- …