Effect of Feeding L-Carnitine and Sunflower Seeds on CLA Content of Pasture-Fed Beef

Pasture finishing enhances levels of conjugated linoleic acids (CLA) in beef lipids (Shanta et al. 1997). CLA (e.g., C18:2 c9, t11), formed during biohydrogenation of polyunsaturated fatty acids (PUFA) in the rumen, can reduce the incidence of heart disease, cancer and obesity in humans. However, pasture finishing cattle can reduce carcass grade. Feeding pasture-fed cattle a high-grain diet for a short finishing period (~60 d) improves grades but may reduce lipid CLA levels. A feeding regime is required that maintains the positive nutritional attributes of pasture-fed beef and improves the meat grade. The objective of this study was to investigate the effects of adding sunflower seeds (SFS), a good source of PUFA (Mir et al. 2000), or carnitine, a vitamin-like compound shown to increase fat deposition and marbling in cattle, to finishing diets of pasture-fed cattle on lipid fatty acid profiles (FAP)

The effect of forage management on carbon storage in pastureland and rotation

Non-Peer ReviewedDegraded land with less than 1.5% organic carbon (class 4 and 5 land) in the Parkland of Western Canada has significant potential, from 5 to 15 Mg C ha-1 depending on management, for carbon storage with forages in the Parkland. The potential ranges from 5 to 15 Mg C ha-1, over a period from 15 to 20 years, depending on fertility management of forages in pasture and initial levels of soil organic carbon. Nitrogen fertilizer increased organic carbon stored in reseeded pastures at Pathlow and Brandon relative to paddocks without fertilizer. Over a period of 12 years (1978-1989) in the Pathlow study, 21.9 Mg C ha- 1 (0-15 cm) was stored when N fertilizer was applied at an annual rate of 45 kg ha-1 compared to the control treatment, which was attributed to accumulation of plant debris and roots at the surface. Increases in organic carbon did not persist 10 years after N fertilizer was discontinued at the study at Pathlow, Saskatchewan. At Brandon, Manitoba, fertilized grass pasture stored 16.2 Mg C ha-1 (0-50 cm) compared to unfertilized bromegrass from 1994 to 1999. Long-term forage rotations at Melfort showed no significant difference in the wheat phase of a F-W-W-H-H-W rotation due to nitrogen fertilizer (147.3 Mg C ha-1 150.7 Mg C ha-1) over a period from 1957 to 1994. This was attributed to the high levels of soil carbon in soils at Melfort. Forages in rotation had no significant effect on organic carbon in a study at Glenlea MB conducted from 1992 to 1999, though a range from 110.8 to 145.7 Mg C ha-1 was observed. Significant differences may occur in the long term as organic carbon accumulates in the treatments at Glenlea

Abdominal functional electrical stimulation to improve respiratory function after spinal cord injury: a systematic review and meta-analysis

Objectives: Abdominal functional electrical stimulation (abdominal FES) is the application of a train of electrical pulses to the abdominal muscles, causing them to contract. Abdominal FES has been used as a neuroprosthesis to acutely augment respiratory function and as a rehabilitation tool to achieve a chronic increase in respiratory function after abdominal FES training, primarily focusing on patients with spinal cord injury (SCI). This study aimed to review the evidence surrounding the use of abdominal FES to improve respiratory function in both an acute and chronic manner after SCI. Settings: A systematic search was performed on PubMed, with studies included if they applied abdominal FES to improve respiratory function in patients with SCI. Methods: Fourteen studies met the inclusion criteria (10 acute and 4 chronic). Low participant numbers and heterogeneity across studies reduced the power of the meta-analysis. Despite this, abdominal FES was found to cause a significant acute improvement in cough peak flow, whereas forced exhaled volume in 1 s approached significance. A significant chronic increase in unassisted vital capacity, forced vital capacity and peak expiratory flow was found after abdominal FES training compared with baseline. Conclusions: This systematic review suggests that abdominal FES is an effective technique for improving respiratory function in both an acute and chronic manner after SCI. However, further randomised controlled trials, with larger participant numbers and standardised protocols, are needed to fully establish the clinical efficacy of this technique

P2X7 Receptor Primes IL-1β and the NLRP3 Inflammasome in Astrocytes Subjected to Mechanical Strain

Inflammatory responses play a key role in many neural pathologies, with localized signaling from non-immune cells making critical contributions. The NLRP3 inflammasome is an important component of innate immune signaling and can link neural insult to chronic inflammation. Stimulation of the NLRP3 inflammasome is a two-stage process. The priming stage involves upregulation of the biosynthesis of the structural components while activation results in their assembly into the actual inflammasome complex and subsequent activation. The priming step can be rate limiting and can connect insult to chronic inflammation but our knowledge of the signals that regulate NLRP3 inflammasome priming in sterile inflammatory conditions is limited. This study examined the link between mechanical strain and inflammasome priming in neural systems. Transient non-ischemic elevation of intraocular pressure (IOP) increased mRNA for inflammasome components IL-1β, NLRP3, ASC, CASP1 and IL-6 in rat and mouse retinas. The P2X7 receptor was implicated in the in vivo mechanosensitive priming of IL-1β and IL-6 transcription and translation. In vitro experiments with optic nerve head astrocytes demonstrated enhanced expression of the IL-1β and IL-6 genes following stretching or swelling. The increase in IL-1β expression was inhibited by degradation of extracellular ATP with apyrase, blocking pannexin hemichannels with carbenoxolone, probenecid or 10Panx1 peptide, P2X7 receptor antagonists (BBG, A839977 or A740003) as well inhibition of the NFκB transcription factor with Bay 11-7082. The swelling-dependent fall in expression of the NFκB inhibitor IκB-α was reduced by treatment of cells with A839977 and in P2X7 knockout mice. In summary, our data suggest that mechanical trauma to the retina results in priming of the NLRP3 inflammasome components and upregulated IL-6 expression and release. This was dependent upon ATP release through pannexin hemichannels and autostimulation of the P2X7 receptor. Since the P2X7 receptor can also trigger inflammasome activation it appears to have a central role in linking mechanical strain to neuroinflammation

Understanding the lived experiences of healthcare professionals during the COVID-19 pandemic : an interpretative phenomenological analysis

Background: Little research has examined the impact of working within the context of COVID-19 on UK healthcare professionals (HCPs) mental health and well-being, despite previous pandemic findings indicating that HCPs are particularly vulnerable to suffering PTSD and other mental health difficulties due to the nature of healthcare work. Specifically, it appears that no research has employed qualitative methodologies to explore the effects of working amidst COVID-19 on mental health for HCPs in the UK. Objective: To qualitatively examining the lived experiences of HCPs in Northern Ireland, working during the early stages of the pandemic and lockdown period (14.04.20 and 29.04.20). Method: Interpretative phenomenological analysis (IPA) was used to explore the experiences of healthcare professionals, who were working during the COVID-19 outbreak. Ten HCPs were recruited via a social media campaign and snowball sampling. All interviews were conducted via telephone and transcribed verbatim. Results: Three superordinate themes with subordinate themes were elicited through the analysis. Theme one centred on specific challenges of HCPs working during the pandemic, such as redeployment, isolation from loved ones, infection concerns, lack of PPE and impact on patient interpersonal care. Theme two offered insights into the mental health and wellbeing of HCPs, while many experienced feelings of fear, sadness and hypervigilance, all also demonstrated a marked resilience. Finally, many felt undervalued and misunderstood, and wished to press upon the general public seriousness of the disease. Conclusion: To the authors’ knowledge this is the first study to explore in depth, the unique experiences of frontline HCPs in Northern Ireland, offering a detailed account of the challenges confronted in these unprecedented circumstances and highlighting support needs within this cohort

Structures of the Ultra-High-Affinity Protein-Protein Complexes of Pyocins S2 and AP41 and Their Cognate Immunity Proteins from Pseudomonas aeruginosa

© 2015 The Authors. Published by Elsevier Ltd. How ultra-high-affinity protein-protein interactions retain high specificity is still poorly understood. The interaction between colicin DNase domains and their inhibitory immunity (Im) proteins is an ultra-high-affinity interaction that is essential for the neutralisation of endogenous DNase catalytic activity and for protection against exogenous DNase bacteriocins. The colicin DNase-Im interaction is a model system for the study of high-affinity protein-protein interactions. However, despite the fact that closely related colicin-like bacteriocins are widely produced by Gram-negative bacteria, this interaction has only been studied using colicins from Escherichia coli. In this work, we present the first crystal structures of two pyocin DNase-Im complexes from Pseudomonas aeruginosa, pyocin S2 DNase-ImS2 and pyocin AP41 DNase-ImAP41. These structures represent divergent DNase-Im subfamilies and are important in extending our understanding of protein-protein interactions for this important class of high-affinity protein complex. A key finding of this work is that mutations within the immunity protein binding energy hotspot, helix III, are tolerated by complementary substitutions at the DNase-Immunity protein binding interface. Im helix III is strictly conserved in colicins where an Asp forms polar interactions with the DNase backbone. ImAP41 contains an Asp-to-Gly substitution in helix III and our structures show the role of a co-evolved substitution where Pro in DNase loop 4 occupies the volume vacated and removes the unfulfilled hydrogen bond. We observe the co-evolved mutations in other DNase-Immunity pairs that appear to underpin the split of this family into two distinct groups

Risk factors for <em>Coxiella burnetii</em> antibodies in bulk tank milk from Danish dairy herds

The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bulk tank milk (BTM) samples from 100 randomly selected Danish dairy cattle herds. Antibody levels were measured by an enzyme-linked immuno-sorbent assay. Before testing the herds, the farm managers were interviewed about hired labour, biosecurity, housing and herd health during the 12 months prior to the study. Variables considered important for C. burnetii antibody positivity in multivariable logistic regression analysis included the sharing of machines between farms (OR = 3.6), human contacts (OR = 4.2), artificial insemination by other people than artificial insemination technicians (OR = 7.7), routine herd health contract with the veterinarian (OR = 4.3) and hygiene precautions taken by veterinarians (OR = 5). In addition, herd size, hired labour, trading of cattle between farms, quarantine and use of calving and disease pens also showed significant association in univariable analysis. This study demonstrates that strict biosecurity is important for the prevention of infections with C. burnetii

Relationship between ecosystem productivity and photosynthetically-active radiation for northern peatlands

We analyzed the relationship between net ecosystem exchange of carbon dioxide (NEE) and irradiance (as photosynthetic photon flux density or PPFD), using published and unpublished data that have been collected during midgrowing season for carbon balance studies at seven peatlands in North America and Europe. NEE measurements included both eddy-correlation tower and clear, static chamber methods, which gave very similar results. Data were analyzed by site, as aggregated data sets by peatland type (bog, poor fen, rich fen, and all fens) and as a single aggregated data set for all peatlands. In all cases, a fit with a rectangular hyperbola (NEE = α PPFD Pmax/(α PPFD + Pmax) + R) better described the NEE-PPFD relationship than did a linear fit (NEE = β PPFD + R). Poor and rich fens generally had similar NEE-PPFD relationships, while bogs had lower respiration rates (R = −2.0μmol m−2s−1 for bogs and −2.7 μmol m−2s−1 for fens) and lower NEE at moderate and high light levels (Pmax = 5.2 μmol m−2s−1 for bogs and 10.8 μmol m−2s−1 for fens). As a single class, northern peatlands had much smaller ecosystem respiration (R = −2.4 μmol m−2s−1) and NEE rates (α = 0.020 and Pmax = 9.2μmol m−2s−1) than the upland ecosystems (closed canopy forest, grassland, and cropland) summarized by Ruimy et al. [1995]. Despite this low productivity, northern peatland soil carbon pools are generally 5–50 times larger than upland ecosystems because of slow rates of decomposition caused by litter quality and anaerobic, cold soils

Relationship between ecosystem productivity and photosynthetically active radiation for northern peatlands

We analyzed the relationship between new ecosystem exchange of carbon dioxide (NEE) and irradiance (as photosynthetic photon flux density of PPFD), using published and unpublished data that have been collected during midgrowing season for carbon balance studies at seven peatlands in North America and Europe. NEE measurements included both eddy-correlation tower and clear, static chamber methods, which gave very similar results. Data were analyzed by site, as aggregated data set for all peatland type (bog, poor fen, rich fen, and all fens) and as a single aggregated data set for all peatlands. In all cases, a fit with a rectangular hyperbola (NEE = PPFD P max (PPFD + PMAX) + R) better described the NEE-PPFD relationships ,while bogs had lower respiration rates (R = -2.0 umol m-2 s-1 for bogs and -2.7 umol m-2 s-1 for fens) and lower NEE at moderate and high light levels (Pmax = 5.2 umol m-2 s-1) than the upland exosystems (closed canopy forest, grassland, and cropland) summarized by Ruimy et al. [1995]. Despite this low productivity, northern peatland soil carbon pools are generally 5-50 times larger than upland ecosystems because of slow rates of decomposition caused by litter quality and anaerobic, cold soils