How much efficiency gains and price reductions for an efficiency defense? 'Quanto Basta'

Potential efficiency gains due to a merger can be used by competition authorities to judge upon proposed mergers. In a world where agents’ efforts, observable or unobservable, affect the success of a production cost reducing project that may be conducted as a stand-alone firm or in a merger, we characterize the merger decision and the type of errors a competition authority may make when it relies on an efficiency defense. In addition, we show that the occurrence of either type of errors is always smaller under the unobservable efforts assumption, than under the observable efforts one.

Two-part tariff licensing mechanisms

Most of the patent licensing agreements that are observed include royalties, in particular per-unit or ad valorem royalties. This paper shows that in a differ entiated duopoly that competes á la Cournot the optimal contract for an internal patentee always includes a positive royalty. Moreover, we show that the patentee would prefer to use ad valorem royalties rather than per-unit royalties when goods are complements or when they are substitutes and the degree of differentiation is suffciently low. The reason is that by including an ad valorem royalty in the licensing contract the patentee can commit strategically to be more (less) aggressive when goods are complements (substitutes) since his licensing revenues become increasing with the price of output of his rival. As a result, licensing may hurt consumers although it always increases social welfare.

Mechanisms implied in Escherichia coli removal during wastewater treatment

Poster presentado 12th Symposium on Aquatic Microbial Ecology (SAME12) August 28 – September 02, 2011 Germany , Rostock–Warnemünde

Antioxidant defense system and family environment in adolescents with family history of psychosis

[EN] Our objective was to determine antioxidant defence activity in healthy controls (HC) and healthy unaffected second-degree relatives of patients with early onset psychosis (HC-FHP),and to assess its relationship with familiar environment measured using the Family Environment Scale (FES). Methods: We included 82 HC and 14 HC-FHP aged between 9 and 17 years. Total antioxidant status,lipid peroxidation, antioxidant enzyme activities and glutathione levels were determined in blood samples. Results:There was a significant decrease in the total antioxidant level in the HC-FHP group compared with the HC group (OR = 2.94; p = 0.009), but no between-group differences in the Global Assessment of Functioning (GAF) scale scores. For the FES, the HC-FHP group had significantly higher scores in the cohesion (p = 0.007) and intellectual-cultural dimensions (p=0.025). After adjusting for these two FES dimensions, total antioxidant status remained significantly different between groups (OR = 10.86, p = 0.009).

USP1 deubiquitinase: cellular functions, regulatory mechanisms and emerging potential as target in cancer therapy

12 p.

Mechanisms Responsible for the Trophic Effect of Beta-Adrenoceptors on the I-to Current Density in Type 1 Diabetic Rat Cardiomyocytes

Background/Aims: In diabetic ventricular myocytes, transient outward potassium current (I-to) amplitude is severely reduced because of the impaired catecholamine release that characterizes diabetic autonomic neuropathy. Sympathetic nervous system exhibits a trophic effect on I-to since incubation of myocytes with noradrenaline restores current amplitude via beta-adrenoceptor (beta AR) stimulation. Here, we investigate the intracellular signalling pathway though which incubation of diabetic cardiomyocytes with the beta AR agonist isoproterenol recovers I-to amplitude to normal values. Methods: Experiments were performed in ventricular myocytes isolated from streptozotocin-diabetic rats. I-to current was recorded by using the patch-clamp technique. Kv4 channel expression was determined by immunofluorescence. Protein-protein interaction was determined by coimmunoprecipitation. Results: Stimulation of beta AR activates first a G alpha s protein, adenylyl cyclase and Protein Kinase A. PKA-phosphorylated receptor then switches to the G alpha i protein. This leads to the activation of the beta AR-Kinase-1 and further receptor phosphorylation and arrestin dependent internalization. The internalized receptor-arrestin complex recruits and activates cSrc and the MAPK cascade, where Ras, c-Raf1 and finally ERK1/2 mediate the increase in Kv4.2 and Kv4.3 protein abundance in the plasma membrane. Conclusion: beta(2)AR stimulation activates a G alpha s and G alpha i protein dependent pathway where the ERK1/2 modulates the Ito current amplitude and the density of the Kv4.2 and Kv4.2 channels in the plasma membrane upon sympathetic stimulation in diabetic heart.

Novel mechanisms for regulation of cell survival and migration by ceramide 1-phosphate

201 p. : gráf.

On the economics of the "meeting competition defense" under the Robinson-Patman Act

Documento de trabajo

Mechanisms of E2F2-mediated transcriptional repression

In this work we wanted to study the mechanism of E2F2-mediated repression. Our hypothesis is that E2F2 activates the expression of one or more E2F members of the “repressor” subset of the family through the E2F motifs present in their promoters, and those repressor E2F(s) would subsequently repress the target promoters. To address this hypothesis, we focused on E2F7. E2F7 is a repressor that lacks the Rb binding domain, and associates with DNA through E2F binding sites (de Bruin et al., 2003). Furthermore, E2F7 itself is also regulated by E2F motifs on its own promoter, and it has been shown to repress DNA metabolism and replication genes in late S-phase (de Bruin et al., 2003; Westendorp et al., 2012). E2F7, together with E2F8 has been found to form heterodimers, being critical on cell proliferation and development, and both seem to have similar functions (Li et al., 2008). Preliminary results from Zubiaga’s group have indicated that E2F2 activates E2F7 transcription in U2OS cells, suggesting that E2F2’s repressor function could be mediated by E2F7. For this purpose, we focused on studying E2F7’s role on the target genes previously known to be repressed by E2F2: Chk1 and Mcm5. The specific aims for this work were the following: - Confirm that E2F2 induces E2F7 in HEK-293T cells - Assess whether E2F7 acts as a transcriptional repressor on E2F sites - Evaluate the role of E2F7 on E2F2-mediated transcriptional repression of Chk1 and Mcm5.

Resveratrol: Anti-Obesity Mechanisms of Action

Resveratrol is a non-flavonoid polyphenol which belongs to the stilbenes group and is produced naturally in several plants in response to injury or fungal attack. Resveratrol has been recently reported as preventing obesity. The present review aims to compile the evidence concerning the potential mechanisms of action which underlie the anti-obesity effects of resveratrol, obtained either in cultured cells lines and animal models. Published studies demonstrate that resveratrol has an anti-adipogenic effect. A good consensus concerning the involvement of a down-regulation of C/EBPa and PPAR. in this effect has been reached. Also, in vitro studies have demonstrated that resveratrol can increase apoptosis in mature adipocytes. Furthermore, different metabolic pathways involved in triacylglycerol metabolism in white adipose tissue have been shown to be targets for resveratrol. Both the inhibition of de novo lipogenesis and adipose tissue fatty acid uptake mediated by lipoprotein lipase play a role in explaining the reduction in body fat which resveratrol induces. As far as lipolysis is concerned, although this compound per se seems to be unable to induce lipolysis, it increases lipid mobilization stimulated by beta-adrenergic agents. The increase in brown adipose tissue thermogenesis, and consequently the associated energy dissipation, can contribute to explaining the body-fat lowering effect of resveratrol. In addition to its effects on adipose tissue, resveratrol can also acts on other organs and tissues. Thus, it increases mitochondriogenesis and consequently fatty acid oxidation in skeletal muscle and liver. This effect can also contribute to the body-fat lowering effect of this molecule.

Mechanisms involved in Escherichia coli and Serratia marcescens removal during activated sludge wastewater treatment

Wastewater treatment reduces environmental contamination by removing gross solids and mitigating the effects of pollution. Treatment also reduces the number of indicator organisms and pathogens. In this work, the fates of two coliform bacteria, Escherichia coli and Serratia marcescens, were analyzed in an activated sludge process to determine the main mechanisms involved in the reduction of pathogenic microorganisms during wastewater treatment. These bacteria, modified to express green fluorescent protein, were inoculated in an activated sludge unit and in batch systems containing wastewater. The results suggested that, among the different biological factors implied in bacterial removal, bacterivorous protozoa play a key role. Moreover, a representative number of bacteria persisted in the system as free-living or embedded cells, but their distribution into liquid or solid fractions varied depending on the bacterium tested, questioning the real value of bacterial indicators for the control of wastewater treatment process. Additionally, viable but nonculturable cells constituted an important part of the bacterial population adhered to solid fractions, what can be derived from the competition relationships with native bacteria, present in high densities in this environment. These facts, taken together, emphasize the need for reliable quantitative and qualitative analysis tools for the evaluation of pathogenic microbial composition in sludge, which could represent an undefined risk to public health and ecosystem functions when considering its recycling.

Analysis of channel quality reporting mechanisms and their impact into 4G and beyond technologies

206 p.

Do Nutritional Supplements Have a Role in Age Macular Degeneration Prevention?

Purpose. To review the proposed pathogenic mechanisms of age macular degeneration (AMD), as well as the role of antioxidants (AOX) and omega-3 fatty acids (omega-3) supplements in AMD prevention. Materials and Methods. Current knowledge on the cellular/molecular mechanisms of AMD and the epidemiologic/experimental studies on the effects of AOX and omega-3 were addressed all together with the scientific evidence and the personal opinion of professionals involved in the Retina Group of the OFTARED (Spain). Results. High dietary intakes of omega-3 and macular pigments lutein/zeaxanthin are associated with lower risk of prevalence and incidence in AMD. The Age-Related Eye Disease study (AREDS) showed a beneficial effect of high doses of vitamins C, E, beta-carotene, and zinc/copper in reducing the rate of progression to advanced AMD in patients with intermediate AMD or with one-sided late AMD. The AREDS-2 study has shown that lutein and zeaxanthin may substitute beta-carotene because of its potential relationship with increased lung cancer incidence. Conclusion. Research has proved that elder people with poor diets, especially with low AOX and omega-3 micronutrients intake and subsequently having low plasmatic levels, are more prone to developing AMD. Micronutrient supplementation enhances antioxidant defense and healthy eyes and might prevent/retard/modify AMD.

Mechanisms of Toxicity of Ag Nanoparticles in Comparison to Bulk and Ionic Ag on Mussel Hemocytes and Gill Cells

Silver nanoparticles (Ag NPs) are increasingly used in many products and are expected to end up in the aquatic environment. Mussels have been proposed as marine model species to evaluate NP toxicity in vitro. The objective of this work was to assess the mechanisms of toxicity of Ag NPs on mussel hemocytes and gill cells, in comparison to ionic and bulk Ag. Firstly, cytotoxicity of commercial and maltose stabilized Ag NPs was screened in parallel with the ionic and bulk forms at a wide range of concentrations in isolated mussel cells using cell viability assays. Toxicity of maltose alone was also tested. LC50 values were calculated and the most toxic Ag NPs tested were selected for a second step where sublethal concentrations of each Ag form were tested using a wide array of mechanistic tests in both cell types. Maltose-stabilized Ag NPs showed size-dependent cytotoxicity, smaller (20 nm) NPs being more toxic than larger (40 and 100 nm) NPs. Maltose alone provoked minor effects on cell viability. Ionic Ag was the most cytotoxic Ag form tested whereas bulk Ag showed similar cytotoxicity to the commercial Ag NPs. Main mechanisms of action of Ag NPs involved oxidative stress and genotoxicity in the two cell types, activation of lysosomal AcP activity, disruption of actin cytoskeleton and stimulation of phagocytosis in hemocytes and increase of MXR transport activity and inhibition of Na-K-ATPase in gill cells. Similar effects were observed after exposure to ionic and bulk Ag in the two cell types, although generally effects were more marked for the ionic form. In conclusion, results suggest that most observed responses were due at least in part to dissolved Ag.

HPV infection, a described cause for human cancer: HPV detection and molecular mechanisms of HPV carcinogenesis (Review).

[en]Human papillomavirus (HPV) belongs to the Papillomaviridae virus family and it is one of the most common sexual transmission infections. HPV genome is composed of eight genes, including two early genes and six late genes. Among these late genes, E6 and E7 code for proteins that trigger cell-cycle re-entry in infected cells, which can lead to cervical cancer development. The IARC (International Agency for Research Cancer) proposed a guideline based on Hill’s criteria to determine whether the relation between HPV infection and cervical cancer is causal or not. Epidemiological studies have demonstrated that HPV infection is a necessary but non-sufficient cause for cervical cancer. Furthermore, HPV infection is considered the first necessary cause described of a human cancer, being HPV16 and 18 carcinogenic to humans and the most studied types. Cervical cancer is the second leading cause of cancer death among women worldwide. Different screening programs are carried out with the aim of preventing cervical cancer; such as cytologies and HPV tests. There are two main methods which are equally usable to detect HPV: the real-time PCR assays and the array assays. Regarding the molecular mechanisms of HPV mediated malignancies, E2, E6 and E7 proteins of HPV16 lead to immune response evasion, inducing IL-10 and TGF-β1 gene expression. Besides, E6 and E7 proteins allow cell-cycle reentry, phosphorylating RB and ubiquitinating p53 respectively. HPV genome integration in host genome leads to the alteration of host and viral genes expression, including oncogenes and tumor suppressor genes. However, the differences of E6 and E7 oncoproteins in different HPV types is poorly known due to the fact that almost the most studied HPV type has been HPV16.