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Mitophagy is a critical intracellular event during the progression of diabetic nephropathy (DN). Our previous study demonstrated that germacrone has anti-ferroptotic properties and is a potential therapeutic agent for DN. However, the relationship among germacrone, mitophagy, and ferroptosis in DN remains unclear. In this study, the data confirmed that germacrone ameliorates high glucose (HG)-induced ferroptosis through limiting Fe (2þ) content and lipid reactive oxygen species (ROS) accumulation in human kidney 2 (HK-2) cells. Germacrone reversed HG-mediated inhibition of mitophagy. Mitophagy inhibition and anabatic mitochondrial ROS abrogate germacrone-mediated protective effects against ferroptotic death, resulting in the subsequent activation of mitochondrial DNA (mtDNA) cytosolic leakage-induced stimulator of interferon response CGAMP interactor 1 (STING) signaling. The combination of a mitochondrial ROS antagonist and germacrone acts synergistically to alleviate the ferroptotic death of tubular cells and DN symptoms. In summary, germacrone ameliorated ferroptotic death in tubular cells by reactivating mitophagy and inhibiting mtDNA-STING signaling in DN. This study provides a novel insight into germacrone-mediated protection against DN progression and further confirms that antioxidant pharmacological strategies facilitate the treatment of DN. [ABSTRACT FROM AUTHOR]

Alginate is an important polysaccharide in the ocean that supports the growth of marine microorganisms. Many widespread Vibrio species possess alginate lyases and can utilize alginate as a carbon source, but the detailed alginate degradation mechanism in Vibrio remains to be further explored. In this study, we obtained a highly efficient alginate-degrading strain, Vibrio pelagius WXL662, with 11 alginate lyases (VpAly-I to -XI) and further elucidated its molecular mechanism of alginate degradation. Three alginate utilization loci (AUL) were identified in different parts of WXL662's genome, comprising six alginate lyases (VpAly-I, -II, -VIII, -IX, -X, and -XI) and other genes related to alginate degradation. Most of the alginate-degrading genes are strongly induced when alginate is provided as the sole carbon source. Ten alginate lyases (VpAly-I to -X) had been purified and characterized, including six from polysaccharide lyase family 7 (PL7), three from PL17, and one from PL6. These recombinant alginate lyases existing in different cellular locations were active at a wide temperature (10 to 50°C) and pH (4.0 to 9.0) range, with different substrate preferences and diverse degradation products, enabling WXL662 to efficiently utilize alginate in a changing marine environment. Importantly, outer membrane vesicles (OMVs) can act as vectors for alginate lyases (VpAly-II, -V, and -VI) in WXL662. Further investigations of public Vibrio genomes revealed that most alginate-degrading vibrios possess one AUL instead of previously reported "scattered" system. These results emphasize the specific alginate degradation strategy in Vibrio pelagius WXL662, which can be used as a model strain to study the ecological importance of effective alginate-degrading vibrios in the ocean. [ABSTRACT FROM AUTHOR]

Improved knowledge of how tea planting age impacts the relationships of soil aggregates with microbial biomass and activity may help understand the mechanisms of improving soil organic matters (OM) sequestration in tea plantation ecosystem. In this study, soil samples (0-20 cm depth) were collected from tea plantations with various ages (8, 17, 25 and 43 years) in the southern Guangxi, China. Soil samples were split into > 2, 2-1, 1-0.25 and < 0.25 mm aggregates following an optimal moisture sieving procedure. Long-term tea planting was favorable to Corg and Nt accumulation in soil aggregates. However, soil aggregate-related microbial biomass (Cmic and Nmic contents) and activity (respiration rate) first increased and then decreased, and their levels were highest in the 17-year tea plantations. After 17 years of tea planting, the disintegration of > 2 mm fractions in soils might partially explain the decreases of microbial biomass and activity. Meanwhile, soil OM availability and soil acidification were also important drivers of the changes in soil microbial biomass and activity during tea planting. Hence, implementing a sustainable management scheme is critical to maintaining microbial community development after 17 years of tea planting, and thus favor nutrient cycling and energy flow in soils. [ABSTRACT FROM AUTHOR]

MiR-381 has been reported to be dysregulated in several human cancers. However, the function and mechanism of miR-381 in colorectal cancer (CRC) remains unclear. In the present study, the miR-381 expression was assessed in a cohort of 113 CRC specimens using real-time quantitative polymerase chain reaction (RTq-PCR), which demonstrated that miR-381 was significantly downregulated in CRC and correlated with distant metastasis and tumor, node, and metastasis (TNM) stage. Functional study revealed that restoration of miR-381 significantly inhibited the invasion, migration, and epithelial-mesenchymal transition (EMT) of CRC cells. Luciferase reporter assay validated that Twist1, an important EMT inducer, was a direct target of miR-381, and rescued Twist1 attenuated the function of miR-381 in CRC cells. Correlation analysis also revealed an inverse correlation between miR-381 and Twist1 expression levels in CRC specimens. Taken together, our results highlight the significance of miR-381/Twist1 interaction in the development and progression of CRC, and suggest that restoration of miR-381 may be a potential therapeutic strategy for the patients with CRC. [ABSTRACT FROM AUTHOR]

Dimethylsulfoniopropionate (DMSP) and related organic sulfur compounds play key roles in global sulfur cycling. Bacteria have been found to be important DMSP producers in seawater and surface sediments of the aphotic Mariana Trench (MT). However, detailed bacterial DMSP cycling in the Mariana Trench subseafloor remains largely unknown. Here, the bacterial DMSP-cycling potential in a Mariana Trench sediment core (7.5 m in length) obtained at a 10,816-m water depth was investigated using culture-dependent and -independent methods. The DMSP content fluctuated along the sediment depth and reached the highest concentration at 15 to 18 cm below the seafloor (cmbsf). dsyB was the dominant known DMSP synthetic gene, existing in 0.36 to 1.19% of the bacteria, and was identified in the metagenome-assembled genomes (MAGs) of previously unknown bacterial DMSP synthetic groups such as Acidimicrobiia, Phycisphaerae, and Hydrogenedentia. dddP, dmdA, and dddX were the major DMSP catabolic genes. The DMSP catabolic activities of DddP and DddX retrieved from Anaerolineales MAGs were confirmed by heterologous expression, indicating that such anaerobic bacteria might participate in DMSP catabolism. Moreover, genes involved in methanethiol (MeSH) production from methylmercaptopropionate (MMPA) and dimethyl sulfide (DMS), MeSH oxidation, and DMS production were highly abundant, suggesting active conversions between different organic sulfur compounds. Finally, most culturable DMSP synthetic and catabolic isolates possessed no known DMSP synthetic and catabolic genes, and actinomycetes could be important groups involved in both DMSP synthesis and catabolism in Mariana Trench sediment. This study extends the current understanding of DMSP cycling in Mariana Trench sediment and highlights the need to uncover novel DMSP metabolic genes/pathways in extreme environments. [ABSTRACT FROM AUTHOR]

This study investigated the effects of beak trimming on a local broiler breed. A total of 648 one-day-old birds were randomly allocated into three treatments: no trimming (NBT), infrared beak trimming (IRBT), and hot-blade beak trimming (HBBT). The performance, beak length, behavior, carcass traits, organ percentages, and meat quality were inspected. The body weight (BW) from 7 to 35 days in the IRBT group was significantly lower than that in the NBT group, and the BW from 7 to 49 days was lower than that in the HBBT group (p < .05). Compared with untrimmed birds, birds in the IRBT group had lower average daily feed intake (ADFI) from 15 to 21 days, and higher heart percentage and L* value in the breast muscle. The upper beak length at 28 and 49 days of age were longest in untrimmed birds, intermediate in birds in the HBBT group, and shortest in the IRBT groups (p <.05). No evidence was found that HBBT caused changes in performance, behavior, carcass traits, organ percentages, and meat quality except for lower change in spleen percentage. Taken together, IRBT had more influence at inhibiting early BW, ADFI, and upper beak length than HBBT in the local broiler breed. [ABSTRACT FROM AUTHOR]

This paper proposes a novel jet-type foam generator of air self-suction intended for dust control in coal mines that overcome the shortcomings of conventional compressed air foam preparation devices. Three non-dimensional numbers of geometric parameters were obtained through theoretical analysis, namely distance-diameter ratio (Rtd),length-diameter ratio (Rld), and area ratio (Rm). And various experiments were conducted to investigate the effects of the three important non-dimensional geometric parameters on air suction properties of the proposed foam generator. The results show that air suction capacity first increases and then decreases with the increasing of Rtd and Rld, and air- water ratio increases with the increasing of Rm. And the optimum distance-diameter ratio is identified to be 1/3-2/3, the optimum length-diameter ratio is approximately 20, and the optimum area ratio should be 81-144. This study provides a solid foundation for application of the proposed foam preparation technology. [ABSTRACT FROM AUTHOR]

The speed of sound in n-octane and isooctane (2,2,4-trimethylpentane) was measured by the Brillouin light scattering (BLS) method. The examined regions for n-octane are T = (297-580) K along five isobaric lines at p = 0.1, 4.0, 7.0, 10.0, and 12.0 MPa for liquid and T = (573-673) K along ten isobaric lines with p = (3.0-10.0) MPa for supercritical fluid. The examined regions for isooctane are T = (294-525) K along five isobaric lines at p = 0.1, 3.0, 6.0, 10.0, and 12.0 MPa for liquid and T = (543-630) K along six isobaric lines with p = (3.0-10.0) MPa for supercritical fluid. The relative expanded uncertainty of the speed of sound is estimated less than 1.3%. Polynomial representations for the speed of sound in liquid n-octane and isooctane were fitted to the experimental results, respectively. The AADs are 0.27% for n-octane and 0.19% for isooctane. The influence of temperature and pressure on the speed of sound was also analyzed. Moreover, the data were also used to assess the predicted ability of three equations of state forn-octane. [ABSTRACT FROM AUTHOR]