Acetaldehyde-reinforcing effects: differences in low-alcohol-drinking (UChA) and high-alcohol-drinking (UChB) rats.

It has been suggested that acetaldehyde has a biphasic effect on voluntary alcohol consumption. At low brain concentration, it might exert reinforcing effects, whereas high acetaldehyde levels would be predominantly aversive. The objective of the current study was to compare the effect of an intraperitoneal dose of acetaldehyde (50 mg/kg) in high-alcohol-drinking (UChB) and low-alcohol-drinking (UChA) rat lines, which differ in the activity of the brain mitochondrial class 2 aldehyde dehydrogenase (ALDH2) as a consequence of differences in their ALDH2 genotypes.

Involvement of brain ethanol metabolism on acute tolerance development and on ethanol consumption in alcohol-drinker (UChB) and non-drinker (UChA) rats.

Acute tolerance that develops in minutes of an ethanol exposure appears to influence voluntary ethanol consumption in our two selected bred lines, UChA (low ethanol drinker) and UChB (high ethanol drinker)rats. We have reported previously that an acute intraperitoneal (ip.) dose of ethanol (2.

Expression of the TGF-beta coreceptor endoglin in epidermal keratinocytes and its dual role in multistage mouse skin carcinogenesis.

Endoglin is an integral membrane glycoprotein primarily expressed in the vascular endothelium, but also found on macrophages and stromal cells. It binds several members of the transforming growth factor (TGF)-beta family of growth factors and modulates TGF-beta(1)-dependent cellular responses. However, it lacks cytoplasmic signaling motifs and is considered as an auxiliary receptor for TGF-beta.

Mutations in mitochondrial aldehyde dehydrogenase (ALDH2) change cofactor affinity and segregate with voluntary alcohol consumption in rats.

Genetic factors influence alcohol consumption and alcoholism. A number of groups have bred alcohol drinker and non drinker rat strains, but genetic determinants remain unknown. The University of Chile rat lines UChA (low drinkers) and UChB (high drinkers) display differences in the relative K(m) for NAD+ of mitochondrial aldehyde dehydrogenase (ALDH2) but no V(max) differences.

Effect of particle size and interparticle force on the fluidization behavior of gas-fluidized beds.

Gas-fluidized powders of fine particles display a fluidlike regime in which the bed does not have a yield strength, it expands uniformly as the gas velocity is increased and macroscopic bubbles are absent. In this paper we test the extension of this fluidlike regime as a function of particle size and interparticle attractive force. Our results show that for sufficiently large particles, bubbling initiates just after the solidlike fluidized regime as it is obtained experimentally by other workers.

Transforming growth factor beta-1 induces snail transcription factor in epithelial cell lines: mechanisms for epithelial mesenchymal transitions.

The Snail transcription factor has been described recently as a strong repressor of E-cadherin in epithelial cell lines, where its stable expression leads to the loss of E-cadherin expression and induces epithelial-mesenchymal transitions and an invasive phenotype. The mechanisms regulating Snail expression in development and tumor progression are not yet known. We show here that transforming growth factor beta-1 (TGFbeta1) induces Snail expression in Madin-Darby canine kidney cells and triggers epithelial-mesenchymal transitions by a mechanism dependent on the MAPK signaling pathway.

Experimental study on the dynamics of gas-fluidized beds.

Gas-fluidized fine powders display three regimes of fluidization: solidlike, fluidlike, and bubbling. We investigate, from both macroscopic and local measurements, the transition between these regimes. We show that the transition between the solidlike and the fluidlike regimes takes place along an interval of gas velocities in which transient active regions alternate with transient solid networks.

Silver halide sensitized gelatin process effects in holographic lenses recorded on Slavich PFG-01 plates.

In this work we study the feasibility of using silver halide sensitized gelatin based on PFG-01 (Slavich) emulsions to construct uniaxial compound lenses. This processing is able to introduce variations in the thickness and refractive index of the emulsion. We prove that these changes are not sufficient to provide the observed variations in Bragg conditions in the reconstruction and that a shear-type effect must exist to explain the performance of processed emulsions.

[Epidural hematoma after catheter removal in a patient without coagulation disorders].

A 69-year-old man with rectal adenocarcinoma and no relevant medical history was scheduled for anterior resection of the tumor under combined anesthesia. The epidural catheter was removed 48 h after surgery. A clinical picture consistent with a diagnosis of epidural hematoma developed gradually and was confirmed by magnetic resonance imaging.

Fine cohesive powders in rotating drums: Transition from rigid-plastic flow to gas-fluidized regime.

We investigate the dynamics of fine cohesive powders inside rotating drums. We show that these powders may be fluidized due to entrapment of ambient gas, and we determine the onset of fluidization. Experimental measurements on the bed expansion as a function of the rotation velocity have been performed.

Transforming growth factor-beta1 modulates matrix metalloproteinase-9 production through the Ras/MAPK signaling pathway in transformed keratinocytes.

Mouse transformed keratinocytes cultured in the presence of transforming growth factor-beta1 (TGF-beta1) acquire a set of morphological and functional properties giving rise to a more motile phenotype that expresses mesenchymal markers. In this work, we present evidence showing that TGF-beta1 stimulates cellular production of MMP-9 (Gelatinase B), a metalloproteinase that plays an important role in tumoral invasion. Our results demonstrate that TGF-beta1stimulates MMP-9 production and MMP-9 promoter activity in a process that depends of the activation of the Ras-ERK1,2 MAP kinase pathway.

Effect of a dose of ethanol on acute tolerance and ethanol consumption in alcohol drinker(UChB) and non-drinker (UChA) rats.

Acute tolerance that develops within minutes of ethanol exposure appears to influence the apparent acute behavioral sensitivity of laboratory animals to ethanol actions. The existence of a correlation between voluntary ethanol consumption and the speed of acquiring acute tolerance has been proposed. In the present paper we investigated the effect of an acute dose of ethanol on tolerance development and on ethanol voluntary consumption in our two selected bred strains, UChA (low ethanol drinker) and UChB (high ethanol drinker) rats.

Effect of acetaldehyde on acute tolerance and ethanol consumption in drinker and nondrinker rats.

Objective: Acetaldehyde (AcH) has been shown to have aversive or reinforcing actions in relation to ethanol consumption. We have previously observed that a pharmacological dose of AcH (50-150 mg/kg) administered intraperitoneally (i.p.

TGF-beta(1) and Smad4 overexpression induce a less invasive phenotype in highly invasive spindle carcinoma cells.

We have examined the effect of transforming growth factor beta(1) (TGF-beta(1)) and overexpression of the Smad4 gene on the phenotype of Car C, a ras mutated highly malignant spindle carcinoma cell line. TGF-beta(1)-treated Car C cells overexpressing Smad4 spread with a flattened morphology with membrane ruffles abundant in vinculin and show a reduction in their invasive abilities. TGF-beta(1) treatment and overexpression of Smad4 also enhanced the production of PAI-1 measured by the activation of the p3TP-lux reporter gene containing a PAI-1-related promoter.

Aversion to acetaldehyde: differences in low-alcohol-drinking (UChA) and high-alcohol-drinking (UChB) rats.

We have previously found the existence of a relation between activity of the brain mitochondrial aldehyde dehydrogenase (ALDH2) and consumption of ethanol in rats of the low-alcohol-drinking (UChA) and the high-alcohol-drinking (UChB) strains. The aim of the present study was to determine whether UChA and UChB rats also differed in sensitivity to the aversive effects of acetaldehyde (AcH). Aversion to AcH was studied by using a conditioned taste aversion (CTA) paradigm.

Partitioned-field uniaxial holographic lenses.

The efficiency and aberration of partitioned-field uniaxial volume holographic compound lenses are theoretically and experimentally studied. These systems increase the image fields of holographic volume lenses, limited by the angular selectivity that is typical of these elements. At the same time, working with uniaxial systems has led to a decrease in aberration because two recording points (that behave as aberration-free points) are used.

Looking for self-organized critical behavior in avalanches of slightly cohesive powders.

We report results from a statistical analysis of avalanches of cohesive powders in a slowly rotated drum. Interparticle adhesion, which diminishes the effect of inertia and whose magnitude strongly fluctuates in a local scale, makes avalanches in slightly cohesive powders eligible for displaying self-organized criticality. However, the results show that avalanche sizes, time interval between avalanches, and maximum stable angle do not follow a power-law distribution.

Aggregation and sedimentation in gas-fluidized beds of cohesive powders.

We present measurements on the settling velocity of gas-fluidized beds of fine cohesive powders. In the solidlike regime (solid volume fraction straight phi>straight phi(c)) particles are static, sustained by enduring contacts. The settling is hindered by interparticle contacts and is a very slow process.

Correlation between bulk stresses and interparticle contact forces in fine powders.

We present measurements of the tensile strength as a function of the consolidation stress for a set of fine cohesive powders (xerographic toners) of 12.7 microm particle size and with a range of concentration of submicron fumed silica as flow control additive. This additive is well known for its ability to control interparticle adhesion force.

Effect of vibration on the stability of a gas-fluidized bed of fine powder.

We have investigated the effect of vibrations on the stability of gas-fluidized beds of fine powders (particle size approximately 10 microm). The powder is uniformly fluidized by an adjustable gas flow that enables us to control the average solid volume fraction straight phi(0). The fluidized bed is then subjected to a vertical oscillatory motion of controlled amplitude and frequency.

Vitamin D(3) promotes the differentiation of colon carcinoma cells by the induction of E-cadherin and the inhibition of beta-catenin signaling.

The beta-catenin signaling pathway is deregulated in nearly all colon cancers. Nonhypercalcemic vitamin D3 (1alpha,25-dehydroxyvitamin D(3)) analogues are candidate drugs to treat this neoplasia. We show that these compounds promote the differentiation of human colon carcinoma SW480 cells expressing vitamin D receptors (VDRs) (SW480-ADH) but not that of a malignant subline (SW480-R) or metastasic derivative (SW620) cells lacking VDR.

Differences in sensitivity to the aversive effects of ethanol in low-alcohol drinking (UChA) and high-alcohol drinking (UChB) rats.

A conditioned taste aversion paradigm was used to determine whether aversion to the pharmacological effects of ethanol, apart from orosensory cues, can contribute to differences in voluntary ethanol consumption in rats of the low-alcohol drinking (UChA) and the high-alcohol drinking (UChB) strains. "Alcohol-naive" UChA and UChB rats were injected intraperitoneally with ethanol (0.5, 1.

Ectopic expression of PA2.26 antigen in epidermal keratinocytes leads to destabilization of adherens junctions and malignant progression.

PA2.26 antigen is a small mucin-type transmembrane glycoprotein induced in mouse epidermal keratinocytes during carcinogenesis. It is located at plasma membrane projections, such as microvilli and ruffles, where it interacts with the actin cytoskeleton.

Effect of naltrexone on acute tolerance to ethanol in UChB rats.

The effect of naltrexone (a non-selective opioid receptor antagonist) on both alcohol consumption in a voluntary selection situation and acute tolerance to the motor impairment effect of ethanol was examined in female high alcohol-drinking (UChB) rats using the tilting plane test. In experiment 1, the effect of naltrexone on alcohol consumption was studied in UChB rats which were given a daily 1-h period access to a 10% (v/v) ethanol solution with food and water always available. Naltrexone in doses of 5 or 10 mg/kg intaperitoneal (i.

Acute tolerance, alcohol sensitivity and drinking pattern in the F2 generation of UChA and UChB rats.

Objective: Studies in mice and rats bred for their behavioral response to ethanol have revealed that there may be a relationship between acute tolerance development, sensitivity to ethanol and alcohol preference. We saw a need to obtain more genetically meaningful correlations between ethanol consumption and acute tolerance to motor impairment or sensitivity to hypothermia induced by ethanol. In the present article, we provide results on acute tolerance, sensitivity to hypothermia and voluntary ethanol consumption in an F2 generation of a cross between inbred UChA (low) and UChB (high) ethanol-consuming rats.