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1.
Yeon Soo Chung Jae Won Song Dae Ho Kim Sook Shin Young Kyung Park Soo Jin Yang Suk Kyung Lim Kun Taek Park Yong Ho Park 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(2):199-206
Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers. 相似文献
2.
Utilization of biochar impregnated with anaerobically digested slurry as slow‐release fertilizer
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We examined the possibility of an environment‐friendly slow‐release fertilizer (SRF) made of biochar impregnated by anaerobically digested slurry. The biochar materials were produced from three types of feedstocks (orange peel, residual wood, water‐treatment sludge) at different temperatures of 300°C, 500°C, and 700°C via pyrolysis. The release behaviors of the water‐soluble K+, Ca2+, and Mg2+ were similar for all impregnated biochars and the commercial SRF used. The water‐retention capacity was greatly improved by mixing the biochar‐SRF with the soil. The yield of lettuce was lower for the biochar‐SRF applications of 3.7 to 34.2 t ha–1 than for the commercial SRF application of 51.4 t ha–1. This might be due to excessive increase of soil pH for the biochar‐SRF application. Based on these results, the authors concluded that the biochar impregnated with nutrients could become an effective slow‐release K+ fertilizer. 相似文献
3.
Aging is a major risk factor for many chronic diseases, such as cancer, cardiovascular disease, and diabetes. The exact mechanisms underlying the aging process are not fully elucidated. However, a growing body of evidence suggests that several pathways, such as sirtuin, AMP-activated protein kinase, insulin-like growth factor, autophagy, and nuclear factor erythroid 2-related factor 2 play critical roles in regulating aging. Furthermore, genetic or dietary interventions of these pathways can extend lifespan by delaying the aging process. Seaweeds are a food source rich in many nutrients, including fibers, polyunsaturated fatty acids, vitamins, minerals, and other bioactive compounds. The health benefits of seaweeds include, but are not limited to, antioxidant, anti-inflammatory, and anti-obese activities. Interestingly, a body of studies shows that some seaweed-derived extracts or isolated compounds, can modulate these aging-regulating pathways or even extend lifespans of various animal models. However, few such studies have been conducted on higher animals or even humans. In this review, we focused on potential anti-aging bioactive substances in seaweeds that have been studied in cells and animals mainly based on their anti-aging cellular and molecular mechanisms. 相似文献
4.
Xu T Shao XL Li QX Keum YS Jing HY Sheng W Li J 《Journal of agricultural and food chemistry》2007,55(10):3764-3770
A competitive enzyme-linked immunosorbent assay (ELISA) for pentachloronitrobenzene (PCNB), a fungicide and chemical intermediate, was developed using a polyclonal antiserum produced against a hapten-protein conjugate of pentachlorophenoxypropionic acid-bovine serum albumin (BSA). An indirect competitive ELISA of PCNB showed an IC50 of 37 ng/mL and a limit of detection (LOD) of 7 ng/mL. The ELISA can tolerate up to 10% (v/v) methanol, 5% (v/v) acetonitrile, or 5% (v/v) acetone without significant fluctuation of Amax and IC50. The assay sensitivity showed little change in a range of pH from 6 to 8 and concentrations of 0.05-0.2 M NaCl in the assay buffer. Very low cross-reactivities were observed for some structurally related compounds except for hexachlorobenzene (12%). The average recoveries of PCNB from fortified well water, river water, and soil samples were in ranges of 88-94, 80-91, and 70-81%, respectively. The correlations between the gas chromatographic and ELISA results were excellent (r 2 >or= 0.97, slopes from 0.86 to 1.10) for those fortified samples. The ELISA is a good alternative tool for monitoring PCNB residues in environmental samples. 相似文献
5.
Nineteen bacterial strains were isolated from petroleum-contaminated soil in Hilo, HI, and characterized by two different spray-plated methods, turbidity test in liquid medium, and 16S rRNA gene sequence analysis. Analysis of the soil showed 13 polycyclic aromatic hydrocarbons (PAHs) in a range from 0.6 to 30 mg/kg of dry weight each and 12 PAH metabolites. Five distinct bacterial strains (C3, C4, P1-1, JS14, and JS19b1) selected from preliminary plating and turbidity tests were further tested for PAH degradation through single PAH degradation assay. Strains C3, C4, and P1-1 degraded phenanthrene (40 mg/L) completely during 7 days of incubation. Strain JS14 degraded fluoranthene (40 mg/L) completely during 10 days of incubation. Strain JS19b1 degraded 100% of phenanthrene (40 mg/L) in 7 days, 77% of fluorene (40 mg/L) in 14 days, 97% of fluoranthene (40 mg/L) in 10 days, and 100% of pyrene (40 mg/L) in 14 days. Turbidity tests showed that strains P1-1, JS14, and JS19b1 utilized several organophosphorus pesticides as growth substrate. P1-1 can degrade carbofenothion, chlorfenvinphos, diazinon, fonofos, and pirimiphos-methyl. JS14 can transform chlorfenvinphos and diazinon. JS19b1 can break down diazinon, pirimiphos-methyl, and temephos. 相似文献
6.
Jung-Hoon Jee Ja-Geun Koo Yoo-Hwa Keum Joon-Suk Kang Kwan H A Park & Ju-Chan Kang 《Aquaculture Research》2007,38(1):26-35
This study investigated the effects of different types of diet and sediment on the growth parameters of juvenile tiger crab Orithyia sinica under laboratory conditions, focusing on survival, growth and moulting. In the first set of experiments, juvenile tiger crabs were reared with five different types of sediment, i.e., soft sand, coarse sand, soft sand mixed with coarse sand, mud or bare bottom. Soft sand resulted in not only the highest survival rate of 78% but also the best rate of growth and feed intake. Crabs reared with a mud substrate showed the worst results in these parameters. The intermoult period, however, was not affected by sediment types. In the second set of experiments, crabs were fed different types of diet to determine their effects on the same growth parameters. Diets were composed of different combinations with Manila clam (Ruditapes philippinarum), brine shrimp (Artemia nauplii), microencapsulated feeds and marine diatom (Chaetoceros gracilis). Survival and growth in crabs fed Manila clam as a diet component were significantly higher than in those on other diets. The highest survival and growth were achieved with a diet that included all four components. These results provide valuable information on the appropriate bottom substrates and diet types necessary for artificial mass culture of the tiger crab. 相似文献
7.
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)- 1,2-isoxazoline as a useful rice herbicide 总被引:1,自引:0,他引:1
Hwang IT Kim HR Jeon DJ Hong KS Song JH Cho KY 《Journal of agricultural and food chemistry》2005,53(22):8639-8643
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline derivative was synthesized, and its herbicidal activity was assessed under glasshouse and flooded paddy conditions. 5-(2,6-Difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 125 g of a.i. ha(-1) under greenhouse conditions. Soil application of this compound showed complete control of barnyard-grass to the fourth leaf stage at 250 g of a.i. ha(-1). Field trials indicated that this compound controlled annual weeds rapidly with a good tolerance on transplanted rice seedlings by post-emergence and soil application. This compound showed a low mammalian and environmental toxicity in various toxicological tests. 相似文献
8.
Chang HR Keum YS Koo SJ Moon JK Kim K Kim JH 《Journal of agricultural and food chemistry》2011,59(5):1918-1923
The in vivo metabolism of a new herbicide pyribenzoxim (benzophenone Ο-[2,6-bis(4,6-dimethoxypyrimidin-2-yloxy)benzoyl]oxime) in rice was carried out using container trials. Two radiolabeled forms of [carbonyl-(14)C]pyribenzoxim (P1) and [ring-(14)C(U)]pyribenzoxim (P2) were treated separately as formulations for foliar treatment by single applications of 50 g of active ingredient (ai)/ha at the 4-6 leaves stage. At 0, 7, 30, and 60 days after treatment (DAT), samples of panicle, foliage/rest of plant, and roots were taken for analysis. Upon harvest (120 DAT), rice plants were separated into grain, husk, straw, and root parts. Total radioactive residues (TRRs) at each sampling date were determined to show that the final radioactive residues at harvest were low in grain, husk, straw, and roots, accounting for <17 ppb. The concentration of final residues in the rice plant decreased rapidly, and less than 0.1% of initial TRRs remained at harvest. At 7 DAT, metabolite 1 [M1, 2,6-bis(4,6-dimethoxypyrimidin-2-yloxy)benzoic acid] and two unknown compounds (other-1 and other-2) were detected in foliage extract, accounting for 3.5% TRRs (21.0 ppb), 3.1% TRRs (19.0 ppb), and 9.0% TRRs (54.3 ppb), respectively, while 26.1% of M1 was observed in solvent wash. Any other metabolites were not detected in the plant, including expected metabolite M3 (benzophenone oxime). On the basis of the results obtained, a metabolic pathway of pyribenzoxim in a rice plant was proposed. 相似文献
9.
Daigeun Kim Ara Jo Bum-Kyoung Seo Kune-Woo Lee Won Ho Park Taek Seung Lee 《Fibers and Polymers》2013,14(12):1993-1998
We report on an azopyridine derivative for probing transition metal ions and fabrication of its films. The probe, AP, showed a sensitive absorption change toward transition metal ions, especially cobalt ion, even at the concentration of ppm range, accompanied by yellow-to-red color transition with noticeable isosbestic point. In addition, the AP-containing PMMA film with high transparency can be fabricated by spin-casting without any aggregation of AP. The film with PMMA matrix shows good sensitivity toward cobalt ion similar to the case in the solution with a feature of metallochromic transition. 相似文献
10.
ABSTRACT The exotic grass, Saccharum spontaneum L., has invaded abandoned agricultural lands in the Panama Canal Watershed for decades. The grass aggressively competes with regenerating tree seedlings preventing natural forest regeneration. To estimate effectual light level for controlling the grass, the growth of S. spontaneum was measured under a range of artificial shading conditions. Five shade treatment subplots–light intensities of 100% (full sunlight), 50, 25, 15, and 5%–were established at each of eight plots in land adjacent to the Panama Canal Watershed. Each site was cleared of S. spontaneum and then the regrowth was harvested. The regrowth of the grass was harvested and measured four times every one and half months for six months. The biomass of S. spontaneum was significantly less in lower light conditions than in full sunlight. The results showed that comparing growth of the grass at each harvest date, except for the first harvest date, there were significant differences between full sunlight and light intensities of 5, 15 and 25%. When compared by different harvest dates for each light level, only full sunlight showed a significant difference in biomass of the grass. The study demonstrates that shading is an effective method for controlling S. spontaneum. The results can be applied to developing reforestation strategies for abandoned lands occupied by S. spontaneum. 相似文献