Israeli Acute Paralysis Virus: Epidemiology, Pathogenesis and Implications for Honey Bee Health

Israeli acute paralysis virus (IAPV) is a widespread RNA virus of honey bees that has been linked with colony losses. Here we describe the transmission, prevalence, and genetic traits of this virus, along with host transcriptional responses to infections. Further, we present RNAi-based strategies for limiting an important mechanism used by IAPV to subvert host defenses. Our study shows that IAPV is established as a persistent infection in honey bee populations, likely enabled by both horizontal and vertical transmission pathways. The phenotypic differences in pathology among different strains of IAPV found globally may be due to high levels of standing genetic variation. Microarray profiles of host responses to IAPV infection revealed that mitochondrial function is the most significantly affected biological process, suggesting that viral infection causes significant disturbance in energy-related host processes. The expression of genes involved in immune pathways in adult bees indicates that IAPV infection triggers active immune responses. The evidence that silencing an IAPV-encoded putative suppressor of RNAi reduces IAPV replication suggests a functional assignment for a particular genomic region of IAPV and closely related viruses from the Family Dicistroviridae, and indicates a novel therapeutic strategy for limiting multiple honey bee viruses simultaneously and reducing colony losses due to viral diseases. We believe that the knowledge and insights gained from this study will provide a new platform for continuing studies of the IAPV–host interactions and have positive implications for disease management that will lead to mitigation of escalating honey bee colony losses worldwide

Exopolysaccharides from the Energy Microalga Strain <i>Botryococcus</i> <i>braunii</i>: Purification, Characterization, and Antioxidant Activity

Botryococcus braunii, a prestigious energy microalga, has recently received widespread attention because it can secrete large amounts of exopolysaccharides (EPS) with potential applications in food, cosmetics, and nutraceuticals. Unfortunately, the insufficiency of research on the bioactivity and structure–activity relationship of B. braunii EPS has impeded the downstream applications. In the present study, alcohol precipitation, deproteinization, and DEAE-cellulose column chromatography were used to extract and purify B. braunii SCS-1905 EPS. It was found that B. braunii SCS-1905 EPS were high-molecular-weight heteropolysaccharides containing uronic acid (7.43–8.83%), protein (2.30–4.04%), and sulfate groups (1.52–1.95%). Additionally, the EPS primarily comprised galactose (52.34–54.12%), glucose (34.60–35.53%), arabinose (9.41–10.32%), and minor amounts of fucose (1.80–1.99%), with the presence of a pyranose ring linked by a β-configurational glycosidic bond. Notably, the antioxidant activity of crude exopolysaccharides (CEPS) was stronger, and the half maximal inhibitory concentration (IC50) for ABTS and hydroxyl radicals was significantly lower than that of deproteinized exopolysaccharides (DEPS). Overall, this study indicated a potential application of B. braunii SCS-1905 EPS as a natural antioxidant. In summary, B. braunii EPS could be used as a potential feedstock for the production of antioxidant health foods

Sm-Nd isochron dating and geochemical (rare earth elements, Sr-87/Sr-86, delta O-18, delta C-13) characterization of calcite veins in the Jiaoshiba shale gas field, China: implications for the mechanisms of vein formation in shale gas systems

The Wufeng and Longmaxi organic-rich shales host the largest shale gas plays in China. This study examined the petrography, rare earth element (REE) and other trace-element geochemistry, Sm-Nd geochronology, and isotope geochemistry (Sr-87/Sr-86, delta O-18, delta C-13) of fracture-cementing minerals within core samples of the Wufeng and Longmaxi Formations from the Jiaoshiba shale gas field in order to (1) characterize the mineral phases occurring in the veins (mineralized fractures); (2) determine the ages of the calcite by the Sm-Nd isochron dating method; (3) understand the sources of calcite-precipitating fluids; and (4) explore the possible mechanisms responsible for calcite vein formation in shale gas systems. The fractures hosted in the Longmaxi Formation are mineralized with quartz as the predominant fracture cement, and calcite as an intracementation phase postdating the earlier quartz cement. In contrast, the fractures hosted in the Wufeng Formation are dominantly mineralized by calcite, which occurs either as the only cement present or as a cement phase predating later quartz cement. Calcite veins within the Longmaxi Formation have a Sm-Nd isochron age of 160 +/- 13 Ma and 6 13 C values of -4.71%c to -3.11%c, delta O-18 values of 17.1%17.4%0, and Sr-87/Sr-86 values of 0.72437-0.72869. Calcite veins within the Wufeng Formation yielded a Sm-Nd isochron age of 133 +/- 15 Ma and are characterized by delta C-13 values of -2.29%c to -1.03%c, delta O-18 values of 17.3%c-17.7%c, and Sr-87/Sr-86 values of 0.72202-0.72648. The similarity between Sr-87/Sr-86 values of the calcite and those of their respective surrounding host rocks (0.72670-0.72875 of the Longmaxi shales; 0.72030-0.72648 of the Wufeng shales), combined with relatively depleted delta C-13 and uniform fluid delta O-18 isotopic features, indicates that the calcite-precipitating fluids within the Wufeng and Longmaxi Formations were derived largely from their respective surrounding host-rock sources. REE data equally indicate that the distinguishable Eu anomalies (6.20-19.35; 4.45-11.91), Y anomalies (1.03-1.50; 1.44-1.70), and Y/Ho ratios (28.80-39.16; 38.86-45.18) of calcite veins within the Longmaxi and Wufeng Formations were controlled by their respective surrounding host rocks. The Sm-Nd isochron ages and fluid inclusion data of fracture cements suggest that fracture opening and calcite precipitation in composite veins within the Wufeng and Longmaxi Formations were triggered by gas generation overpressurization

miR-31-5p Promotes Oxidative Stress and Vascular Smooth Muscle Cell Migration in Spontaneously Hypertensive Rats via Inhibiting FNDC5 Expression

Oxidative stress and the migration of vascular smooth muscle cells (VSMCs) are important for vascular remodeling in a variety of vascular diseases. miR-31-5p promotes cell migration in colorectal cancer cells but inhibits cell migration in renal cell carcinoma. However, whether miR-31-5p is involved in oxidative stress and VSMC migration remains unknown. This study shows the crucial roles of miR-31-5p in oxidative stress and VSMC migration, as well as underlying mechanisms. Experiments were carried out in primary VSMCs from aortic media of Wistar–Kyoto rats (WKY) and spontaneously hypertensive rats (SHR), as well as the A7r5 cell line. Oxidative stress was assessed by NADPH oxidase (NOX) expression, NOX activity, and reactive oxygen species (ROS) production. Cell migration was evaluated with a Boyden chamber assay and a wound healing assay. The miR-31-5p mimic and inhibitor promoted and attenuated oxidative stress and cell migration in the VSMCs of SHR, respectively. A dual-luciferase reporter assay indicated that miR-31-5p targeted the 3’UTR domain of FNDC5. The miR-31-5p level was raised and FNDC5 expression was reduced in the VSMCs of SHR compared with those of WKY. The miR-31-5p mimic reduced FNDC5 expression in the A7r5 cells and the VSMCs of both WKY and SHR, while the miR-31-5p inhibitor only increased FNDC5 expression in the VSMCs of SHR. Exogenous FNDC5 attenuated not only the oxidative stress and VSMC migration in SHR but also the roles of the miR-31-5p mimic in inducing oxidative stress and VSMC migration. These results indicate that miR-31-5p promotes oxidative stress and VSMC migration in SHR via inhibiting FNDC5 expression. The increased miR-31-5p and reduced FNDC5 in the VSMCs of SHR contribute to enhanced oxidative stress and cell migration

Associations between emerging chlorinated polyfluoroalkyl ether sulfonic acids exposure and birth size

As an alternative to legacy perfluorooctane sulfonate (PFOS), the wide usage of chlorinated polyfluoroalkyl ether sulfonic acid (Cl-PFESA) in China has generated considerable concerns. The study aimed to investigate the associations between cord serum emerging Cl-PFESA (6:2 Cl-PFESA and 8:2 Cl-PFESA) levels and suboptimal birth size, including low birth weight (LBW), macrosomia, small or large for gestational age (SGA or LGA) among 1048 newborns in Wuhan, China. 6:2 Cl-PFESA and 8:2 Cl-PFESA were 0.76 ng/mL and 0.03 ng/mL, respectively, higher than previously reported levels in newborns from other cities in China. We did not find significant associations between the Cl-PFESAs and suboptimal birth size when considering each Cl-PFESA as a single exposure. However, when integrating emerging Cl-PFESAs and legacy PFASs (PFOS and perfluorooctanoate acid (PFOA)) as a mixture using Bayesian kernel machine regression (BKMR) models, we found that the mixture of legacy PFASs and emerging Cl-PFESAs had inverse associations with SGA and LGA. Two legacy PFASs and two Cl-PFESAs had similar contributions to the association with SGA, whereas the majority of the association with LGA was driven by PFOS. The results demonstrated these legacy PFASs were still the predominant PFASs associated with suboptimal birth size while emerging Cl-PFESAs had a less but nonnegligible contribution to the association with SGA. Further studies in different regions with varied Cl-PFESA levels are needed to replicate the associations