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At least 1,585 records · Page 88
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Identification of aberrant circular RNA expression and its potential clinical value in primary great saphenous vein varicosities

Highlights: • This study identified 232 significantly aberrant circRNAs in primary great saphenous vein varicosities (PGSVVs). • A circRNA-miRNA-gene co-expression network was created. • Hsa{sub c}irc{sub 0}006427, hsa{sub c}irc{sub 0}089810 and hsa{sub c}irc{sub 0}005267 might be potential biological markers for PGSVVs. This study aimed to identify aberrant circRNA expression in primary great saphenous vein varicosities (PGSVVs) and investigate its potential clinical significance. High-throughput sequencing was applied to analyze the differential expression of circRNAs in three paired vein samples of PGSVVs and a control group. Computational bioinformatics analyses, including gene ontology (GO) analysis and encyclopedia of genes and genomes (KEGG) pathway analysis, were performed to further enrich microRNA data. Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to verify the selected aberrant circRNAs in all vein samples, and a receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic and potential clinical significance. A total of 232 circRNAs were significantly aberrantly expressed in PGSVVs, including 105 and 127 upregulated and downregulated circRNAs, respectively. The predicted top 10 downstream miRNAs of the significantly altered circRNAs are hsa-miR-103a-2-5p, hsa-miR-141-5p, hsa-miR-3692-5p, hsa-miR-4659a-3p, hsa-miR-4659b-3p, hsa-miR-4691-5p, hsa-miR-4778-3p, hsa-miR-6738-3p, hsa-miR-6792-3p and hsa-miR-6873-3p. GO analysis revealed that the most enriched and meaningful biological process, cellular component, and molecular function terms were related to the regulation of catabolic processes, the cytoplasm and ATP binding, respectively. The most enriched and meaningful pathways revealed by KEGG pathway analysis were related to “axon guidance” “vitamin digestion and absorption” and “NF-Kappa B signaling pathway”. Hsa{sub c}irc{sub 0}006427 (P = 0.007), hsa{sub c}irc{sub 0}089810 (P = 0.044) and hsa{sub c}irc{sub 0}005267 (P = 0.049) were significantly downregulated in the PGSVV group relative to their expression levels in the control group, and the area under the ROC curve was 0.9091, 0.8025 and 0.8148, respectively. This study demonstrated that circRNAs were differentially expressed in PGSVVs, and highlights the crucial roles of circRNAs in the pathogenesis of PGSVVs and indicates that hsa{sub c}irc{sub 0}006427, hsa{sub c}irc{sub 0}089810 and hsa{sub c}irc{sub 0}005267 might be potential diagnostic and clinical biological markers.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Association of circular Klotho and insulin-like growth factor 1 with cardiac hypertrophy indexes in athlete and non-athlete women following acute and chronic exercise

Highlights: • Acute and chronic exercises have a stimulatory effect on plasma IGF-I and Klotho. • Plasma IGF-I has an association with exercise-induced cardiac hypertrophy especially LVEDDI and LVMI. • Klotho acts as a negative regulator for exercise-induced cardiac hypertrophy most probably through modulating IGF-I effect. Owing to the role of insulin-like growth factor 1 (IGF-I) in cardiac hypertrophy and the ability of Klotho in inhibiting the IGF-I action, we investigated effects of exercise on plasma Klotho and IGF-I and their association with cardiac hypertrophy. In this study, 10 non-athlete and 10 athlete women underwent a Bruce test (acute exercise) and 12-weeks water aerobics training (chronic exercise). Electrocardiographic parameters, plasma IGF-I and Klotho levels were measured in different time courses. The exercise training could significantly increase left ventricular end-diastolic diameter index (LVEDDI) in the non-athletes. Plasma levels of IGF-I significantly increased following acute and chronic exercises. The Klotho levels at the baseline were higher in athletes than non-athletes and its levels significantly increased immediately after acute exercise in both groups. The Klotho levels significantly decreased in non-athletes 24 h after chronic exercise, but its level was still higher than the baseline in the athletes. We found positive and negative correlations between cardiac hypertrophy indexes (LVEDDI and left ventricular mass index) with respectively IGF-I and Klotho. In conclusion, we found a stimulatory effect of acute and chronic exercises on plasma IGF-I and Klotho and association of IGF-I with exercise-induced cardiac hypertrophy. Moreover, Klotho could act as a negative regulator for exercise-induced cardiac hypertrophy.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Plastic waste upcycling toward a circular economy

Large amounts of plastics are discarded worldwide each year, leading to a significant mass of waste in landfills and pollution to soil, air, and waterways. Upcycling is an efficient way to transform plastic waste into high-value products and can significantly lessen the environmental impact of plastic production/consumption. In this article, current advances and future directions in plastic waste upcycling technologies are discussed. In particular, this review focuses on the production of high-value materials from plastic waste conversion methods, including pyrolysis, gasification, photoreforming, and mechanical reprocessing. Plastic waste compositions, conversion products, reaction mechanisms, catalyst selection, conversion efficiencies, polymer design, and polymer modification are also explored. Furthermore, the main challenges facing the adoption and scale-up of these technologies are highlighted. Suggestions are given for focusing future research and development to increase the efficiency of upcycling practices.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2018

Combining biotechnology with circular bioeconomy: From poultry, swine, cattle, brewery, dairy and urban wastewaters to biohydrogen

Highlights: • Poultry, swine, cattle, brewery, dairy and urban WWs could be microalga-based treated. • Removal efficiency ranges were 95–100% for N, 63–99% for P and 48–70% for COD. • Higher biohydrogen production yield was obtained using poultry and swine wastewaters. The ability of microalgae to grow in nutrient-rich environments and to accumulate nutrients from wastewaters (WW) makes them attractive for the sustainable and low-cost treatment of WW. The valuable biomass produced can be further used for the generation of bioenergy, animal feed, fertilizers, and biopolymers, among others. In this study, Scenedesmus obliquus was able to remove nutrients from different wastewaters (poultry, swine and cattle breeding, brewery and dairy industries, and urban) with removal ranges of 95–100% for nitrogen, 63–99% for phosphorus and 48–70% for chemical oxygen demand. The biomass productivity using wastewaters was higher (except for poultry) than in synthetic medium (Bristol), the highest value being obtained in brewery wastewater (1025 mg/(L.day) of freeze-dried biomass). The produced biomass contained 31–53% of proteins, 12–36% of sugars and 8–23% of lipids, regardless of the type of wastewater. The potential of the produced Scenedesmus obliquus biomass for the generation of BioH{sub 2} through batch dark fermentation processes with Enterobacter aerogenes was evaluated. The obtained yields ranged, in mL H{sub 2}/g Volatile Solids (VS), from 50.1 for biomass from anaerobically digested cattle WW to 390 for swine WW, whereas the yield with biomass cultivated in Bristol medium was 57.6 mL H{sub 2}/g{sub VS}.

60 APPLIED LIFE SCIENCES↗