Lack of uniqueness for weak solutions of the incompressible porous media equation

In this work we consider weak solutions of the incompressible 2-D porous media equation. By using the approach of De Lellis-Sz\'ekelyhidi we prove non-uniqueness for solutions in $L^\infty$ in space and time.Comment: 23 pages, 2 fugure

Effectiveness of Chitosan Films Impregnated With Ciprofloxacin for the Prophylaxis of Osteomyelitis in Open Fractures: An Experimental Study in Rats

Background: The systemic antimicrobial prophylaxis is the standard treatment in the prevention of osteomyelitis after open fractures, with topical application of antimicrobials as an alternative due to their high concentrations at the site of the fracture, low systemic concentrations and fewer side effects. Objectives: This study aimed to evaluate the effectiveness of prophylaxis of osteomyelitis through experimental model of open fractures with the use of chitosan films, whether or not impregnated with ciprofloxacin. Materials and Methods: In this experimental study, 24 Holtzman rats were distributed into 4 groups of 6 rats each. The CT (control of treatment) group: an open fracture model treated with systemic antimicrobial; the IC (infection control) group: an open fracture untreated model; the C (chitosan) group: an open fracture model treated using a chitosan film; and the CA (chitosan with antimicrobial) group: an open fracture model treated using a chitosan film impregnated with antimicrobial. After 3 weeks the animals were killed by an overdose of anesthetic, and a fragment osseous was removed for histological and microbiological analysis. The comparisons between the groups considered significant values of P ≤ 0.05. Results: In cultures of the CT group, there was less bacterial growth compared to the results of the cultures of the IC (P = 0.005), C (P = 0.005) and CA (P = 0.009) groups. The inflammation was lower in the CT group compared to the IC (P = 0.014), C (P = 0.001) and CA (P = 0.007) groups. Conclusions: In this experimental model of open fracture, the chitosan film pure or impregnated with ciprofloxacin was not effective in the prophylaxis of osteomyelitis

Effects of dietary salt on gene and protein expression in brain tissue of a model of sporadic small vessel disease

Background: The effect of salt on cerebral small vessel disease (SVD) is poorly understood. We assessed the effect of dietary salt on the cerebral tissue of the strokeprone spontaneously hypertensive rat (SHRSP) - a relevant model of sporadic SVD - at both the gene and protein level. Methods: Brains from 21 week old SHRSP and Wistar-Kyoto rats, half additionally salt-loaded (via a 3 week regime of 1% NaCl in drinking water) were split into 2 hemispheres and sectioned coronally – one hemisphere for mRNA microarray and qRT-PCR, the other for immunohistochemistry using a panel of antibodies targeting components of the neurovascular unit. Results: We observed differences in gene and protein expression affecting the acute phase pathway and oxidative stress (ALB, AMBP, APOH, AHSG and LOC100129193, up-regulated in salt-loaded WKY versus WKY, >2-fold), active microglia (increased Iba-1 protein expression in salt-loaded SHRSP versus saltloaded WKY, p<0.05), vascular structure (ACTB & CTNNB, up-regulated in saltloaded SHRSP versus SHRSP, >3-fold; CLDN-11,VEGF and VGF downregulated >- 2-fold in salt-loaded SHRSP versus SHRSP) and myelin integrity (MBP downregulated in salt loaded WKY rats versus WKY, >2.5-fold). Changes of salt-loading were more pronounced in SHRSP and occurred without an increase in blood pressure in WKY rats. Conclusion: Salt exposure induced changes in gene and protein expression in an experimental model of SVD and its parent rat strain in multiple pathways involving components of the glio-vascular unit. Further studies in pertinent experimental models at different ages would help clarify the short and long-term effect of dietary salt in SVD

The absence of an auditory-visual attentional blink is not due to echoic memory.

Als binnen een halve seconde twee visuele items in een serieel aangeboden stroom moeten worden geselecteerd, is de prestatie voor het tweede item vaak relatief slecht (er treedt een “attentional blink” op); wanneer het eerste echter item auditief wordt aangeboden, verdwijnt de blink meestal. We hebben aangetoond dat dit laatste niet wordt veroorzaakt doordat proefpersonen hun echoïsch geheugen gebruiken om de verwerking van het auditieve item uit te stellen tot na het einde van de visuele stroom

Novel role for the innate immune receptor toll-like receptor 4 (TLR4) in the regulation of the wnt signaling pathway and photoreceptor apoptosis

Recent evidence has implicated innate immunity in regulating neuronal survival in the brain during stroke and other neurodegenerations. Photoreceptors are specialized light-detecting neurons in the retina that are essential for vision. In this study, we investigated the role of the innate immunity receptor TLR4 in photoreceptors. TLR4 activation by lipopolysaccharide (LPS) significantly reduced the survival of cultured mouse photoreceptors exposed to oxidative stress. With respect to mechanism, TLR4 suppressed Wnt signaling, decreased phosphorylation and activation of the Wnt receptor LRP6, and blocked the protective effect of the Wnt3a ligand. Paradoxically, TLR4 activation prior to oxidative injury protected photoreceptors, in a phenomenon known as preconditioning. Expression of TNFα and its receptors TNFR1 and TNFR2 decreased during preconditioning, and preconditioning was mimicked by TNFα antagonists, but was independent of Wnt signaling. Therefore, TLR4 is a novel regulator of photoreceptor survival that acts through the Wnt and TNFα pathways. © 2012 Yi et al

Spatially uninformative sounds increase sensitivity for visual motion change

It has recently been shown that spatially uninformative sounds can cause a visual stimulus to pop out from an array of similar distractor stimuli when that sound is presented in temporal proximity to a feature change in the visual stimulus. Until now, this effect has predominantly been demonstrated by using stationary stimuli. Here, we extended these results by showing that auditory stimuli can also improve the sensitivity of visual motion change detection. To accomplish this, we presented moving visual stimuli (small dots) on a computer screen. At a random moment during a trial, one of these stimuli could abruptly move in an orthogonal direction. Participants’ task was to indicate whether such an abrupt motion change occurred or not by making a corresponding button press. If a sound (a short 1,000 Hz tone pip) co-occurred with the abrupt motion change, participants were able to detect this motion change more frequently than when the sound was not present. Using measures derived from signal detection theory, we were able to demonstrate that the effect on accuracy was due to increased sensitivity rather than to changes in response bias

Fine-mapping of 5q12.1-13.3 unveils new genetic contributors to caries

Caries is a multifactorial disease and little is still known about the host genetic factors influencing susceptibility. Our previous genome-wide linkage scan has identified the interval 5q12.1–5q13.3 as linked to low caries susceptibility in Filipino families. Here we fine-mapped this region in order to identify genetic contributors to caries susceptibility. Four hundred and seventy-seven subjects from 72 pedigrees with similar cultural and behavioral habits and limited access to dental care living in the Philippines were studied. DMFT scores and genotype data of 75 single-nucleotide polymorphisms were evaluated in the Filipino families with the Family-Based Association Test. For replication purposes, a total 1,467 independent subjects from five different populations were analyzed in a case-control format. In the Filipino cohort, statistically significant and borderline associations were found between low caries experience and four genes spanning 13 million base pairs (PART1, ZSWIM6, CCNB1, and BTF3). We were able to replicate these results in some of the populations studied. We detected PART1 and BTF3 expression in whole saliva, and the expression of BTF3 was associated with caries experience. Our results suggest BTF3 may have a functional role in protecting against caries.Fil: Shimizu, T.. Nihon University of Dentistry; JapónFil: Deeley, K.. University of Pittsburgh; Estados UnidosFil: Briseño Ruiz, J.. University of Pittsburgh; Estados UnidosFil: Faraco Junior, I. M.. University of Pittsburgh; Estados UnidosFil: Poletta, Fernando Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; ArgentinaFil: Brancher, J. A.. Pontifical Catholic University of Paraná; BrasilFil: Pecharki, G. D.. Pontifical Catholic University of Paraná; BrasilFil: Küchler, E. C.. Universidade Federal Fluminense; BrasilFil: Tannure, P. N.. Universidade Federal do Rio de Janeiro; BrasilFil: Lips, A.. Universidade Federal do Rio de Janeiro; BrasilFil: Vieira, T. C. S.. Universidade Federal Fluminense; BrasilFil: Patir, A.. Istanbul Medipol Universit; TurquíaFil: Yildirim, M.. Istanbul University; TurquíaFil: Mereb, J. C.. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Resick, J. M.. University of Pittsburgh; Estados UnidosFil: Brandon, C. A.. University of Pittsburgh; Estados UnidosFil: Cooper, M. E.. University of Pittsburgh; Estados UnidosFil: Seymen, F.. Istanbul University; TurquíaFil: Costa, M. C.. Universidade Federal do Rio de Janeiro; BrasilFil: Granjeiro, J. M.. Universidade Federal Fluminense; BrasilFil: Trevilatto, P. C.. Pontifical Catholic University of Paraná; BrasilFil: Orioli, I. M.. Universidade Federal do Rio de Janeiro; Brasil. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; ArgentinaFil: Castilla, Eduardo Enrique. Instituto Oswaldo Cruz; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; ArgentinaFil: Marazita, M. L.. University of Pittsburgh; Estados UnidosFil: Vieira, A. R.. University of Pittsburgh; Estados Unido

The acetylation of RelA in Lys310 dictates the NF-κB-dependent response in post-ischemic injury

The activation of nuclear factor kappa B (NF-κB) p50/RelA is a key event in ischemic neuronal injury, as well as in brain ischemic tolerance. We tested whether epigenetic mechanisms affecting the acetylation state of RelA might discriminate between neuroprotective and neurotoxic activation of NF-κB during ischemia. NF-κB activation and RelA acetylation were investigated in cortices of mice subjected to preconditioning brain ischemia or lethal middle cerebral artery occlusion (MCAO) and primary cortical neurons exposed to preconditioning or lethal oxygen-glucose deprivation (OGD). In mice subjected to MCAO and in cortical neurons exposed to lethal OGD, activated RelA displayed a high level of Lys310 acetylation in spite of reduced total acetylation. Also, acetylated RelA on Lys310 interacted strongly with the CREB-binding protein (CBP). Conversely, RelA activated during preconditioning ischemia appeared deacetylated on Lys310. Overexpressing RelA increased Bim promoter activity and neuronal cell death both induced by lethal OGD, whereas overexpressing the acetylation-resistant RelA-K310R, carrying a mutation from Lys310 to arginine, prevented both responses. Pharmacological manipulation of Lys310 acetylation by the sirtuin 1 activator resveratrol repressed the activity of the Bim promoter and reduced the neuronal cell loss. We conclude that the acetylation of RelA in Lys310 dictates NF-κB-dependent pro-apoptotic responses and represents a suitable target to dissect pathological from neuroprotective NF-κB activation in brain ischemia