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81.
A. Rigotto S.R. Cotta A.C.F. Dias J.L.N. Carvalho F.D. Andreote 《Letters in applied microbiology》2020,71(5):444-450
Sugarcane cultivation supports Brazil as one of the largest world sugar and ethanol producer. In order to understand the impact of changing sugarcane harvest from manual to mechanized harvest, we studied the effect of machinery traffic on soil and consequently soil compaction upon soil microbial communities involved in nitrogen cycling. The impact of sugarcane harvest was dependent on soil depth and texture. At deeper soil layers, mechanized harvesting increases the abundance of nitrogen fixers and denitrifying communities (specifically nosZ clade I and II) while manual harvesting increases the abundance of ammonia oxidizers (specifically AOA) and increases denitrifying communities (nosZ clade I and II) on top and at intermediate depth. The effect of change on the harvest system is more evident on sandy soil than on clay soil, where soil indicators of compaction (bulk density and penetration resistance) were negatively correlated with soil microorganisms associated with the nitrogen cycle. Our results point to connections between soil compaction and N transformations in sugarcane fields, besides naming biological variables to be used as proxies for alterations in soil structure. 相似文献
82.
Hisao Tsukamoto Yoshihiro Kubo David L. Farrens Mitsumasa Koyanagi Akihisa Terakita Yuji Furutani 《The Journal of biological chemistry》2015,290(45):27176-27187
Melanopsins play a key role in non-visual photoreception in mammals. Their close phylogenetic relationship to the photopigments in invertebrate visual cells suggests they have evolved to acquire molecular characteristics that are more suited for their non-visual functions. Here we set out to identify such characteristics by comparing the molecular properties of mammalian melanopsin to those of invertebrate melanopsin and visual pigment. Our data show that the Schiff base linking the chromophore retinal to the protein is more susceptive to spontaneous cleavage in mammalian melanopsins. We also find this stability is highly diversified between mammalian species, being particularly unstable for human melanopsin. Through mutagenesis analyses, we find that this diversified stability is mainly due to parallel amino acid substitutions in extracellular regions. We propose that the different stability of the retinal attachment in melanopsins may contribute to functional tuning of non-visual photoreception in mammals. 相似文献
83.
Julie A. Eclov Qingwen Qian Rebecca Redetzke Quanhai Chen Steven C. Wu Chastity L. Healy Steven B. Ortmeier Erin Harmon Gregory C. Shearer Timothy D. O’Connell 《Journal of lipid research》2015,56(12):2297-2308
Heart failure with preserved ejection fraction (HFpEF) is half of all HF, but standard HF therapies are ineffective. Diastolic dysfunction, often secondary to interstitial fibrosis, is common in HFpEF. Previously, we found that supra-physiologic levels of ω3-PUFAs produced by 12 weeks of ω3-dietary supplementation prevented fibrosis and contractile dysfunction following pressure overload [transverse aortic constriction (TAC)], a model that resembles aspects of remodeling in HFpEF. This raised several questions regarding ω3-concentration-dependent cardioprotection, the specific role of EPA and DHA, and the relationship between prevention of fibrosis and contractile dysfunction. To achieve more clinically relevant ω3-levels and test individual ω3-PUFAs, we shortened the ω3-diet regimen and used EPA- and DHA-specific diets to examine remodeling following TAC. The shorter diet regimen produced ω3-PUFA levels closer to Western clinics. Further, EPA, but not DHA, prevented fibrosis following TAC. However, neither ω3-PUFA prevented contractile dysfunction, perhaps due to reduced uptake of ω3-PUFA. Interestingly, EPA did not accumulate in cardiac fibroblasts. However, FFA receptor 4, a G protein-coupled receptor for ω3-PUFAs, was sufficient and required to block transforming growth factor β1-fibrotic signaling in cultured cardiac fibroblasts, suggesting a novel mechanism for EPA. In summary, EPA-mediated prevention of fibrosis could represent a novel therapy for HFpEF. 相似文献
84.
Robert M Bennett Ronald Friend Kim D Jones Rachel Ward Bobby K Han Rebecca L Ross 《Arthritis research & therapy》2009,11(4):R120-14
Introduction
The Fibromyalgia Impact Questionnaire (FIQ) is a commonly used instrument in the evaluation of fibromyalgia (FM) patients. Over the last 18 years, since the publication of the original FIQ, several deficiencies have become apparent and the cumbersome scoring algorithm has been a barrier to widespread clinical use. The aim of this paper is to describe and validate a revised version of the FIQ: the FIQR. 相似文献85.
Cornelis L Verweij 《Arthritis research & therapy》2009,11(3):115-2
Tumor necrosis factor (TNF) antagonists are approved worldwide for the treatment of rheumatoid arthritis (RA). Clinical experience
revealed that TNF-blocking therapy is effective for only approximately two thirds of patients, reflecting that there are 'responders'
as well as 'nonresponders'. Given the destructive nature of RA, the risk of adverse effects, and considerable costs for therapy,
there is a strong need to make predictions on success before the start of therapy. In the current issue of Arthritis Research & Therapy, Hueber and colleagues become the first to present a multi-parameter serum protein biomarker set that has predictive value
prior to the start of anti-TNF treatment. Ultimately, this finding may contribute to a personalized form of medicine, whereby
a specific therapy will be applied that is best suited to an individual patient. 相似文献
86.
F. L. Laksmana P. J. A. Hartman Kok H. Vromans H. W. Frijlink K. Van der Voort Maarschalk 《AAPS PharmSciTech》2009,10(3):732-742
Next to the coating formulation, process conditions play important roles in determining coating quality. This study aims to
develop an operational window that separates layering from agglomeration regimes and, furthermore, the one that leads to the
best coating quality in a fluidized bed coater. The bed relative humidity and the droplet size of the coating aerosol were
predicted using a set of engineering models. The coating quality was characterized using a quantitative image analysis method,
which measures the coating thickness distribution, the total porosity, and the pore size in the coating. The layering regime
can be achieved by performing the coating process at a certain excess of the viscous Stokes number (ΔSt
v). This excess is dependent on the given bed relative humidity and droplet size. The higher the bed relative humidity, the
higher is the ΔSt
v required to keep the process in the layering regime. Further, it is shown that using bed relative humidity and droplet size
alone is not enough to obtain constant coating quality. The changes in bed relative humidity and droplet size have been identified
to correlate to the fractional area of particles sprayed per unit of time. This parameter can effectively serve as an additional
parameter to be considered for a better control on the coating quality. High coating quality is shown to be achieved by performing
the process close to saturation and spraying droplets small enough to obtain high spraying rate, but not too small to cause
incomplete coverage of the core particles. 相似文献
87.
C. A. Kreikemeier T. B. Engle K. L. Lucot S. D. Kachman T. E. Burkey D. C. Ciobanu 《Animal genetics》2015,46(2):205-208
Tumor necrosis factor alpha (TNF‐α) is a pro‐inflammatory cytokine with a role in activating adaptive immunity to viral infections. By inhibiting the capacity of plasmacytoid dendritic cells to produce interferon‐α and TNF‐α, porcine circovirus 2 (PCV2) limits the maturation of myeloid dendritic cells and impairs their ability to recognize viral and bacterial antigens. Previously, we reported QTL for viremia and immune response in PCV2‐infected pigs. In this study, we analyzed phenotypic and genetic relationships between TNF‐α protein levels, a potential indicator of predisposition to PCV2 co‐infection, and PCV2 susceptibility. Following experimental challenge with PCV2b, TNF‐α reached the peak at 21 days post‐infection (dpi), at which time a difference was observed between pigs that expressed extreme variation in viremia and growth (P < 0.10). A genome‐wide association study (n = 297) revealed that genotypes of 56 433 SNPs explained 73.9% of the variation in TNF‐α at 21 dpi. Major SNPs were identified on SSC8, SSC10 and SSC14. Haplotypes based on SNPs from a SSC8 (9 Mb) 1‐Mb window were associated with variation in TNF‐α (P < 0.02), IgG (P = 0.05) and IgM (P < 0.13) levels at 21 dpi. Potential overlap of regulatory mechanisms was supported by the correlations between genomic prediction values of TNF‐α and PCV2 antibodies (21 dpi, r > 0.22), viremia (14–21 dpi, P > 0.29) and viral load (r = 0.31, P < 0.0001). Characterization of the QTL regions uncovered genes that could influence variation in TNF‐α levels as well as T‐ and B‐cell development, which can affect disease susceptibility. 相似文献
88.
89.
90.
Tiffany M. Nuessle Nicole L. Garneau Meghan M. Sloan Stephanie A. Santorico 《Journal of visualized experiments : JoVE》2015,(100)
The goal of the Denver Papillae Protocol is to use a dichotomous key to define and prioritize the characteristics of fungiform papillae (FP) to ensure consistent scoring between scorers. This protocol builds off of a need that has arisen from the last two decades of taste research using FP as a proxy for taste pore density. FP density has historically been analyzed using Miller & Reedy’s 1990 characterizations of their morphology: round, stained lighter, large, and elevated. In this work, the authors forewarned that stricter definitions of FP morphology needed to be outlined. Despite this call to action, follow up literature has been scarce, with most studies continuing to cite Miller & Reedy’s original work. Consequently, FP density reports have been highly variable and, combined with small sample sizes, may contribute to the discrepant conclusions on the role of FP in taste sensitivity. The Genetics of Taste Lab explored this apparent inconsistency in counting and found that scorers were individually prioritizing the importance of these characteristics differently and had no guidance for when a papilla had some, but not all, of the reported qualities of FP. The result of this subjectivity is highly variable FP counts of the same tongue image. The Denver Papillae Protocol has been developed to remedy this consequence through use of a dichotomous key that further defines and prioritizes the importance of the characteristics put forth by Miller & Reedy. The proposed method could help create a standard way to quantify FP for researchers in the field of taste and nutritional studies. 相似文献