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131.
Tall fescue toxicosis and ergot alkaloids cost U.S. livestock producers approximately one billion dollars in annual livestock production loss annually. Ergovaline (EV) is the tall fescue alkaloid primarily responsible for clinical disease in livestock. Since native ruminal microorganisms have not been attributed to the detoxification of EV, finding detoxifying microbes from other environments is desirable. One possible source for potential microorganisms that can degrade EV is the anaerobic gut of the earthworm, Eisenia fetida. This study describes a comparative microbial analysis of earthworm digestive tracts receiving 10,000 ppb EV (E+ treatment) when compared with a control treatment with no detectable amounts of EV (E− treatment). An HPLC assay determined a 25% loss of EV from the E+ treatment was microbial in nature. A community microbiomic approach of constructing 16S-rRNA gene clone libraries was used to compare the microbes affected by the two treatments. RDPII tools such as Classifier and Libcompare were used in the analysis of 16S sequences. DOTUR analysis was used to examine the richness and diversity of the two microbial populations in these experiments. The results indicate there are few significant differences in the microbial community structure between the two microbiomes.  相似文献   
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Artemisia pallens Wall. ex DC., popularly known as davana, has gained considerable attention because of its unique fragrance, high economic value, and pharmacological properties. The compositional complexity of davana essential oil (DO) has been a challenge for quality control. In this study, the chemical profile of DO was developed using polarity-based fractionation and a combination of gas chromatographic (GC-FID), hyphenated chromatographic (GC/MS), and spectroscopic (Fourier-Transform Infra-Red, 1D, 2D-Nuclear Magnetic Resonance) techniques. The analysis led to the identification of ninety-nine compounds. Major components of the DO were cis-davanone (D3, 53.0 %), bicyclogermacrene (6.9 %), trans-ethyl cinnamate (4.9 %), davana ether isomer (3.4 %), spathulenol (2.8 %), cis-hydroxy davanone (2.4 %), and trans-davanone (2.1 %). The study led to identifying several co-eluting novel minor components, which could help determine the authenticity of DO. The rigorous column-chromatography led to the isolation of five compounds. Among these, bicyclogermacrene, trans-ethyl cinnamate, and spathulenol were isolated and characterized by spectroscopic methods for the first time from DO. Pharmacological profile revealed that the treatment of DO and D3 inhibited the production of pro-inflammatory cytokines (TNF-α, IL-6) induced by lipopolysaccharide (LPS) in primary macrophages without any cytotoxic effect after administration of their effective concentrations. The result of this study indicates the suitability of DO and D3 for further investigation for the treatment of chronic skin inflammatory conditions.  相似文献   
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Climate warming has yielded earlier ice break‐up dates in recent decades for lakes leading to water temperature increases, altered habitat, and both increases and decreases to ecosystem productivity. Within lakes, the effect of climate warming on secondary production in littoral and pelagic habitats remains unclear. The intersection of changing habitat productivity and warming water temperatures on salmonids is important for understanding how climate warming will impact mountain ecosystems. We develop and test a conceptual model that expresses how earlier ice break‐up dates influence within lake habitat production, water temperatures and the habitat utilized by, resources obtained and behavior of salmonids in a mountain lake. We measured zoobenthic and zooplankton production from the littoral and pelagic habitats, thermal conditions, and the habitat use, resource use, and fitness of Brook Trout (Salvelinus fontinalis). We show that earlier ice break‐up conditions created a "resource‐rich" littoral–benthic habitat with increases in zoobenthic production compared to the pelagic habitat which decreased in zooplankton production. Despite the increases in littoral–benthic food resources, trout did not utilize littoral habitat or zoobenthic resources due to longer durations of warm water temperatures in the littoral zone. In addition, 87% of their resources were supported by the pelagic habitat during periods with earlier ice break‐up when pelagic resources were least abundant. The decreased reliance on littoral–benthic resources during earlier ice break‐up caused reduced fitness (mean reduction of 12 g) to trout. Our data show that changes to ice break‐up drive multi‐directional results for resource production within lake habitats and increase the duration of warmer water temperatures in food‐rich littoral habitats. The increased duration of warmer littoral water temperatures reduces the use of energetically efficient habitats culminating in decreased trout fitness.  相似文献   
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Recent evidence reveals that prolactin gene expression (PRL-GE) in mammotropes occurs in pulses, but the molecular process(es) underlying this phenomenon remains unclear. Earlier, we have identified an E-box (E-box133) in the rat PRL promoter that binds several circadian elements and is critical for this dynamic process. Preliminary analysis revealed a Pit-1 binding site (P2) located immediately adjacent to this E-box133 raising the possibility that some type of functional relationship may exist between these two promoter regions. In this study, using serum shocked GH3 cell culture system to synchronize PRL-GE activity, we determined that Pit-1 gene expression occurred in pulses with time phases similar to that for PRL. Interestingly, EMSA analysis not only confirmed Pit-1 binding to the P2 site, but also revealed an interaction with factor(s) binding to the adjacent E-box133 promoter element. Additionally, down-regulation of Pit-1 by siRNA reduced PRL levels during pulse periods. Thus, using multiple evidences, our results demonstrate clearly that the Pit-1 P2 site is necessary for PRL-GE elaboration. Furthermore, the proximity of this critical Pit-1 binding site (P2) and the E-box133 element coupled with the evidences of a site-to-site protein interactions suggest that the process of PRL-GE pulse activity might involve more dynamic and intricate cross-talks between promoter elements that may span some, or all, of the proximal region of the PRL promoter in driving its pulsatile expression.  相似文献   
136.
Several non‐invasive Raman spectroscopy‐based assays have been reported for rapid and sensitive detection of pathogens. We developed a novel statistical model for the detection of RNA viruses in saliva, based on an unbiased selection of a set of 65 Raman spectral features that mostly attribute to the RNA moieties, with a prediction accuracy of 91.6% (92.5% sensitivity and 88.8% specificity). Furthermore, to minimize variability and automate the downstream analysis of the Raman spectra, we developed a GUI‐based analytical tool “RNA Virus Detector (RVD).” This conceptual framework to detect RNA viruses in saliva could form the basis for field application of Raman Spectroscopy in managing viral outbreaks, such as the ongoing COVID‐19 pandemic. ( http://www.actrec.gov.in/pi-webpages/AmitDutt/RVD/RVD.html ).  相似文献   
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Differential expression of miRNAs has been linked with lung carcinogenesis. Recent studies have indicated that DNA hypermethylation can lead to silencing of tumor suppressor miRNA-encoding genes. Restoration of tumor suppressor miRNAs using inhibitors of DNA methyltransferases has been shown to suppress cell proliferation, angiogenesis, invasion and metastasis implying that modulation of methylation of specific miRNAs can be used as novel therapeutic targets in lung cancer. In this review, we highlight tremendous progress which has been made in the identification of methylation-mediated silencing of miRNAs and their contribution in lung carcinogenesis along with the clinical utility of methylated miRNAs.  相似文献   
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