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Inflammation is a major risk factor for development of colorectal cancer (CRC). Prostaglandin synthase cyclooxygenase-2 (COX-2) encoded by the PTGS2 gene is the rate limiting enzyme in prostaglandin synthesis and therefore plays a distinct role as regulator of inflammation.PTGS2 mRNA levels were determined in intestinal tissues from 85 intestinal adenoma cases, 115 CRC cases, and 17 healthy controls. The functional PTGS2 polymorphisms A-1195G (rs689466), G-765C (rs20417), T8473C (rs5275) were assessed in 200 CRC cases, 991 adenoma cases and 399 controls from the Norwegian KAM cohort.PTGS2 mRNA levels were higher in mild/moderate adenoma tissue compared to morphologically normal tissue from the same individual (P

The ABCB1/MDR1 gene product ABCB1/P-glycoprotein is implicated in the development of colorectal cancer (CRC). NFKB1 encodes transcription factors regulating expression of a number of genes including ABCB1. We have previously found association between the ABCB1 C-rs3789243-T polymorphism and CRC risk and interactions between the ABCB1 C-rs3789243-T and C3435T polymorphisms and meat intake in relation to CRC risk (Andersen, BMC Cancer, 2009, 9, 407). ABCB1 and NFKB1 mRNA levels were assessed in intestinal tissue from 122 CRC cases, 101 adenoma cases (12 with severe dysplasia, 89 with mild-moderate dysplasia) and from 18 healthy individuals, together with gene polymorphisms in ABCB1 and NFKB1. ABCB1 mRNA levels were highest in the healthy individuals and significantly lower in mild/moderate and severe dysplasia tissue (P

Significant mass-transport resistances in polymer-electrolyte-fuel-cell catalyst layers (CLs) impose a lower limit on Pt-loading levels, hindering wide-spread fuel-cell commercialization. The origin of this resistance remains unclear. Minimization of CL mass-transport resistance is imperative to achieve better CL design and performance. In this paper, an operando method based on H2 limiting current is used to characterize and quantify CL resistance in traditional porous Pt/carbon-based electrodes. CL sub-resistances are isolated using continuum multiscale modeling and experiments, investigating the effects of reactant molecular weight, pressure, and ionomer to carbon weight ratio. The results expose CL resistance including both interfacial and transport components, although the majority of the CL resistance is ascribed to a local resistance close to the Pt reaction sites, which includes interfacial resistance and local transport resistance. Variations in temperature, humidity, and primary particle loading (Pt:C ratio) highlight the impact of operating conditions and CL design parameters on CL sub-resistances. The observed trends guide optimization of CL design to achieve novel low-loaded fuel-cell electrodes.

Reducing mass-transport losses in polymer-electrolyte fuel cells (PEFCs) is essential to increase their power density and reduce overall stack cost. At the same time, cost also motivates the reduction in expensive precious-metal catalysts, which results in higher local transport losses in the catalyst layers. In this paper, we use a hydrogen-pump limiting-current setup to explore the gas-phase transport losses through PEFC catalyst layers and various gas-diffusion and microporous layers. It is shown that the effective diffusivity in the gas-diffusion layers is a strong function of liquid saturation. In addition, it is shown how the catalyst layer unexpectedly contributes significantly to the overall measured transport resistance. This is especially true for low catalyst loadings. It is also shown how the various losses can be separated into different mechanisms including diffusional processes and mass-dependent and independent ones, where the data suggests that a large part of the transport resistance in catalyst layers cannot be attributed to a gas-phase diffusional process. The technique is promising for deconvoluting transport losses in PEFCs.

Phytoplankton photosynthesis links global ocean biology and climate-driven fluctuations in the physical environment. These interactions are largely expressed through changes in phytoplankton physiology, but physiological status has proven extremely challenging to characterize globally. Phytoplankton fluorescence does provide a rich source of physiological information long exploited in laboratory and field studies, and is now observed from space. Here we evaluate the physiological underpinnings of global variations in satellite-based phytoplankton chlorophyll fluorescence. The three dominant factors influencing fluorescence distributions are chlorophyll concentration, pigment packaging effects on light absorption, and light-dependent energy-quenching processes. After accounting for these three factors, resultant global distributions of quenching-corrected fluorescence quantum yields reveal a striking consistency with anticipated patterns of iron availability. High fluorescence quantum yields are typically found in low iron waters, while low quantum yields dominate regions where other environmental factors are most limiting to phytoplankton growth. Specific properties of photosynthetic membranes are discussed that provide a mechanistic view linking iron stress to satellite-detected fluorescence. Our results present satellite-based fluorescence as a valuable tool for evaluating nutrient stress predictions in ocean ecosystem models and give the first synoptic observational evidence that iron plays an important role in seasonal phytoplankton dynamics of the Indian Ocean. Satellite fluorescence may also provide a path for monitoring climate-phytoplankton physiology interactions and improving descriptions of phytoplankton light use efficiencies in ocean productivity models.

This article examines the effects of nonpulsatile blood flow on the vascular system in patients with left ventricular assist devices (LVADs). The study included 59 patients with continuous-flow LVADs, with 30 patients having nonpulsatile flow and 29 patients having pulsatile flow. The results showed that patients with nonpulsatile flow had a trend towards a larger intima area compared to those with pulsatile flow. Additionally, the relative intima thickness in relation to the total vessel wall increased over time in patients with nonpulsatile flow. These findings suggest that long-term nonpulsatile flow during LVAD support may lead to the development of atherosclerosis and increased fragility of arterial vessels. Further research is needed to fully understand the long-term morphological changes. [Extracted from the article]

The article discusses the broader implications of natural hazards on public health, emphasizing the need for a holistic approach to disaster response. Topics discussed include the long-term health consequences of disasters, the impact of Typhoon Haiyan on the Philippines, and recommendations for improving disaster preparedness and response through government-community partnerships and research investment.

ABSTRACT This study explores the dynamics of immune gene expression, ruminal metabolome, and gut microbiota in cows due to the duration of high-grain feeding, shedding light on host response and microbial dynamics in parallel. Cows consumed forage for a week, then gradually transitioned to a high-grain diet, which they consumed for 4 weeks. Immune response was evaluated in ruminal papillae by expression of genes related to the nuclear factor-kappaB (NFkB) pathway and correlated with the microbiota. Rumen metabolome was evaluated with high-performance liquid chromatography coupled with mass spectrometry and anion-exchange chromatography. Rumen and fecal microbiota were evaluated with 16S rRNA gene amplicon sequencing. In the rumen, expression of inflammation-associated genes increased with the duration on high grain, indicating activation of pro-inflammatory cascades; microbial diversity decreased with a high-grain diet but stabilized after week 3 on high grain. Changes in microbial relative abundance and metabolite enrichment were observed throughout the 4 weeks on high grain, with increments in propionogenic taxa (i.e., Succinivibrionaceae). Metabolite enrichment analysis showed that at the start of high-grain feeding, simple carbohydrates were enriched; then, these were substituted by their fermentation products. There were correlations between certain ruminal bacterial taxa (i.e., Ruminococcaceae UCG-005) and expression of genes of the NFkB pathway, suggesting the influence of these taxa on host immune response. In feces, microbial diversity and several Ruminococcaceae members initially declined but recovered by weeks 3 and 4. Overall, despite the stabilization of microbial diversity, changes in microbial relative abundance and proinflammatory genes were observed throughout high-grain feeding, suggesting that cows need more than 4 weeks to fully adjust once consuming a high-grain diet.IMPORTANCEDespite the stepwise diet transition typically assumed to serve for animal adaptation, expression of signaling receptors, mediators, and downstream targets of nuclear factor-kappaB pathway were found throughout the 4 weeks on high grain, which correlated with changes in the rumen microbial profile. In addition, although microbial diversity recovered in the feces and stabilized in the rumen in week 3 on high grain, we observed changes in microbial relative abundance throughout the 4 weeks on high grain, suggesting that cows need more than 4 weeks to adjust once consuming this diet. Findings are particularly important to consider when planning experiments involving dietary changes.