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1.
Journal of Soils and Sediments - To understand the impact of geochemical sedimentation history for arsenic (As) distribution in the sediment profiles of the Hetao Basin, we (1) evaluated sediments...  相似文献   
2.
The present trials tested the efficiency of surplus spermine to reduce inflammation and oxidative stress following LPS‐induced stress using an in vitro model of head kidney and liver cells isolated from Atlantic salmon. Spermine did not protect cells from LPS‐induced inflammatory response at either 0.3, 0.6 or 0.9 mM. However, as the gene expression of spermidine/spermine N1‐acetyltransferase (SSAT) increased with increasing spermine concentration, we addressed possible oxidative effects of the increased SSAT using its activator DENSPM or inhibitor of polyamine oxidation of the acetylated polyamines using MDL72527 at a spermine concentration of 0.6 mM. There was no significant effect of DENSPM, but MDL72527 decreased gene expression of GPX‐3 (p = .04), while gene expression of catalase and MnSOD was unaffected by treatment (p = .30 and p = .48, respectively). In conclusion, spermine did not protect cells from LPS‐provoked inflammation. The higher the spermine concentration, the more SSAT producing acetylated spermine occurred. Inhibiting the acetylated polyamine oxidases by MDL72527 improved oxidation status as expected due to a lower endogenous production of H2O2 by polyamine and acetylated polyamine oxidases. Probably care should be taken using polyamines or arginine as functional ingredients to avoid any increased oxidation within cells.  相似文献   
3.
Piscine orthoreovirus infects various salmonid fish species, and the infection is associated with diseases such as heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar). There are no vaccines available or genetically selected resistant hosts that can efficiently control piscine orthoreovirus (PRV) infection. Currently, the only prophylactic measure against PRV is general biosecurity measures aiming to break the transmission cycle. Methods to eradicate infectious virus from contaminated facilities are desirable, but the knowledge on how to inactivate PRV is lacking. A major bottleneck for inactivation studies is the lack of ability to propagate PRV in cell culture. Therefore, in this study we developed an in vivo model for detection of infectious PRV particles after treatment of the virus with inactivation tools such as heat, pH, iodine, UV and commercially available disinfectants. The results show that standard iodine treatment is efficient in inactivation of the virus, and similarly are high and low pH extremes and treatment with Virocid, a commercially available disinfectant. A UV dose of at least 50 mJ/cm2 is required for inactivation, and the virus has high resistance against heat treatment.  相似文献   
4.
Journal of Plant Diseases and Protection - This study explores the food plant spectrum of the sugar beet weevil (Asproparthenis punctiventris Germar; Coleoptera: Curculionidae), one of the most...  相似文献   
5.
As clinical toxoplasmosis is not considered a problem in pigs, the main reason to implement a control strategy against Toxoplasma gondii (T. gondii) in this species is to reduce the establishment of T. gondii tissue cysts in pork, consequently reducing the risk of the parasite entering the human food chain. Consumption of T. gondii tissue cysts from raw or undercooked meat is one of the main sources of human infection, with infected pork being considered a high risk. This study incorporates a mouse bioassay with molecular detection of T. gondii DNA to study the effectiveness of vaccination (incomplete S48 strain) in its ability to reduce tissue cyst burden in pigs, following oocyst (M4 strain) challenge. Results from the mouse bioassay show that 100% of mice which had received porcine tissues from vaccinated and challenged pigs survived compared with 51.1% of mice which received tissues from non-vaccinated and challenged pigs. The presence (or absence) of T. gondii DNA from individual mouse brains also confirmed these results. This indicates a reduction in viable T. gondii tissue cysts within tissues from pigs which have been previously vaccinated with the S48 strain. In addition, the study demonstrated that the main predilection sites for the parasite were found to be brain and highly vascular muscles (such as tongue, diaphragm, heart and masseter) of pigs, while meat cuts used as human food such as chop, loin, left tricep and left semitendinosus, had a lower burden of T. gondii tissue cysts. These promising results highlight the potential of S48 strain tachyzoites for reducing the number of T. gondii tissues cysts in pork and thus improving food safety.  相似文献   
6.
The marine environment is a rich source of biologically active molecules for the treatment of human diseases, especially cancer. The adaptation to unique environmental conditions led marine organisms to evolve different pathways than their terrestrial counterparts, thus producing unique chemicals with a broad diversity and complexity. So far, more than 36,000 compounds have been isolated from marine micro- and macro-organisms including but not limited to fungi, bacteria, microalgae, macroalgae, sponges, corals, mollusks and tunicates, with hundreds of new marine natural products (MNPs) being discovered every year. Marine-based pharmaceuticals have started to impact modern pharmacology and different anti-cancer drugs derived from marine compounds have been approved for clinical use, such as: cytarabine, vidarabine, nelarabine (prodrug of ara-G), fludarabine phosphate (pro-drug of ara-A), trabectedin, eribulin mesylate, brentuximab vedotin, polatuzumab vedotin, enfortumab vedotin, belantamab mafodotin, plitidepsin, and lurbinectedin. This review focuses on the bioactive molecules derived from the marine environment with anticancer activity, discussing their families, origin, structural features and therapeutic use.  相似文献   
7.
Discrimination between nestmates and non‐nestmates in social insects is thought to rely on the pattern of cuticular hydrocarbons. We investigated the cuticular hydrocarbon profiles of 2 parapatric sibling ant species, Temnothorax nylanderi (Förster, 1850) and Temnothorax crassispinus (Karavaiev, 1926), and their hybrid. We found that although the profiles show considerable similarities, a discriminant analysis based on the relative peak areas of cuticular hydrocarbons separates the 3 taxa. The profiles of hybrids were not consistently intermediate between those of the paternal species, suggesting either non‐additive interactions among the parental biosynthetic pathways or systematic differences in environment‐derived odor cues.  相似文献   
8.
Recycling of greenhouse irrigation water in hydroponic tomato production requires a water remediation process to reduce the risk of pathogen proliferation and the accumulation of other chemical compounds. The dissolution of ozone into bulk irrigation solutions is an effective technology for reducing chemical contaminant and pathogen levels in greenhouse irrigation water. Greenhouse managers utilizing ozonation typically remove residual ozone prior to distribution to the crop. Removal of the active compound in this treatment process has been deemed a prudent measure intended to prevent ozone-based plant damage. This said, although atmospheric ozone has been extensively studied with respect to its phytotoxicity, there are very few studies available on ozone in the aqueous phase in which evidence to support the removal of ozone (on the basis of phytotoxicity) is provided. Furthermore, removal limits the overall efficacy of the treatment as the ozone is not available to treat distribution lines and emitters. The purpose of this study was to determine if aqueous ozone impacts tomato (Lycopersicon esculentum Mill. cv Matrix F1) productivity when applied directly to a mineral wool growth substrate via drip irrigation. At the highest aqueous ozone treatment level (3.0 mg L−1) significant increases in leaf area, shoot dry matter, and stem thickness were observed. There were no differences across all treatments in terms of net CO2 assimilation rate, stomatal conductance, internal leaf CO2 concentration, chlorophyll content index, and fruit production. A qualitative assessment of algae growth on the substrate surface was conducted. Both ozone treatments resulted in a visually discernible reduction in algae prevalence on the substrate surface. The results of this study do not support the removal of aqueous ozone (at the concentrations examined) prior to distribution when the solution is applied via drip irrigation in mineral wool hydroponic tomato production.  相似文献   
9.
10.
Conifers and other trees are constantly adapting to changes in light conditions, water/nutrient supply and temperatures by physiological and morphological modifications of their foliage. However, the relationship between physiological processes and anatomical characteristics of foliage has been little explored in trees. In this study we evaluated needle structure and function in Norway spruce families exposed to different light conditions and transpiration regimes. We compared needle characteristics of sun-exposed and shaded current-year needles in a control plot and a thinned plot with 50% reduction in stand density. Whole-tree transpiration rates remained similar across plots, but increased transpiration of lower branches after thinning implies that sun-exposed needles in the thinned plot were subjected to higher water stress than sun-exposed needles in the control plot. In general, morphological and anatomical needle parameters increased with increasing tree height and light intensity. Needle width, needle cross-section area, needle stele area and needle flatness (the ratio of needle thickness to needle width) differed most between the upper and lower canopy. The parameters that were most sensitive to the altered needle water status of the upper canopy after thinning were needle thickness, needle flatness and percentage of stele area in needle area. These results show that studies comparing needle structure or function between tree species should consider not only tree height and light gradients, but also needle water status. Unaccounted for differences in needle water status may have contributed to the variable relationship between needle structure and irradiance that has been observed among conifers.  相似文献   
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