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121.
Tomasz Wo&#x;kowicz Katarzyna Zacharczuk Rafa&#x; Gierczy&#x;ski Magdalena Nowakowska Katarzyna Piekarska 《International journal of molecular sciences》2021,22(17)
Background: Salmonella Kentucky belongs to zoonotic serotypes that demonstrate that the high antimicrobial resistance and multidrug resistance (including fluoroquinolones) is an emerging problem. To the best of our knowledge, clinical S. Kentucky strains isolated in Poland remain undescribed. Methods: Eighteen clinical S. Kentucky strains collected in the years 2018–2019 in Poland were investigated. All the strains were tested for susceptibility to 11 antimicrobials using the disc diffusion and E-test methods. Whole genome sequences were analysed for antimicrobial resistance genes, mutations, the presence and structure of SGI1-K (Salmonella Genomic Island and the genetic relationship of the isolates. Results: Sixteen of 18 isolates (88.9%) were assigned as ST198 and were found to be high-level resistant to ampicillin (>256 mg/L) and quinolones (nalidixic acid MIC ≥ 1024 mg/L, ciprofloxacin MIC range 6–16 mg/L). All the 16 strains revealed three mutations in QRDR of GyrA and ParC. The substitutions of Ser83 → Phe and Asp87 → Tyr of the GyrA subunit and Ser80→Ile of the ParC subunit were the most common. One S. Kentucky isolate had qnrS1 in addition to the QRDR mutations. Five of the ST198 strains, grouped in cluster A, had multiple resistant determinants like blaTEM1-B, aac(6′)-Iaa, sul1 or tetA, mostly in SGI1 K. Seven strains, grouped in cluster B, had shorter SGI1-K with deletions of many regions and with few resistance genes detected. Conclusion: The results of this study demonstrated that a significant part of S. Kentucky isolates from humans in Poland belonged to ST198 and were high-level resistant to ampicillin and quinolones. 相似文献
122.
《Journal of dairy science》2021,104(11):11474-11485
The industrialization of the agri-food industry and resultant decrease in the number of people employed on farms has contributed to a knowledge gap among consumers about food production processes. A commonly reported concern of dairy consumers is the use of antibiotics in dairy animals, even though these drugs are an important tool for promoting animal health and welfare and food safety. The extent to which consumers are aware of antibiotic residue avoidance practices in dairy production is unknown, and it is unclear whether acquisition of such knowledge could affect purchasing behavior and perceptions of dairy farming. The objectives of this study were to assess consumers' perceptions about the quality and production of dairy products in the United States and determine whether educational materials on processes that limit the occurrence of antibiotic residues in milk can change consumers' perceptions of dairy products and purchasing behaviors. We surveyed 804 consumers and assigned them to 1 of 3 interventions: (1) a control arm (reading the content of the Dairy page of the USDA's myplate.gov website); (2) an educational brochure on the processes that prevent antibiotic residues in milk; and (3) a video on the same processes. We found that a majority (86.1%) of participants believe that the quality of dairy products in the United States is high, although many had concerns about the treatment of dairy animals and chemicals (pesticides, antibiotics, hormones) in dairy products. Compared with the control intervention, the brochure was associated with a significant decrease in the level of concern consumers had about chemicals in their milk [−0.20 points on a Likert scale, 95% confidence interval (CI), −0.32 to −0.08] and a significantly increased comfort in purchasing conventional dairy products (odds ratio 2.43, 95% CI, 1.62 to 3.66). The video was associated with even stronger effects: a 0.29-unit decrease in the level of concern about chemicals in milk (95% CI, −0.42 to −0.016) and 2.94 times greater odds of purchasing conventional dairy products (95%, CI 1.92 to 4.49). Although consumer food decision making is complex and driven by multiple factors, it appears that education about the processes that promote food safety can reassure consumers about their concerns and potentially affect purchasing habits. 相似文献
123.
以4-氟苯胺为原料,经N-乙酰化、硝化合成2-硝基-4-氟乙酰苯胺,所得产物经酸性水解脱乙酰基得4-氟-2-硝基苯胺,然后经溴化、重氮化、脱重氮基得1-溴-3-氟-5-硝基苯,最后经氰化合成了目标产物3-氟-5-硝基苯甲氰.产物用1HNMR进行表征. 相似文献
124.
林可霉素制药废水中含有残留的抗生素和溶酶,同时还有不少生物发酵所产生的生物难降解物质,属高浓度难降解有机废水。采用厌氧折流板反应器对废水进行前期处理。运行结果表明:COD、pH值、SS等参数有很大改善,废水的可生化性大大加强。 相似文献
125.
126.
土壤无机矿物对抗生素的吸附机理研究进展 总被引：3，自引：0，他引：3
抗生素作为一类离子型有机污染物被大量引入环境,对动物及人类的潜在危害已经不可忽视。吸附/解吸则主要控制着抗生素的环境迁移、转化与归宿,土壤有机质与无机矿物对抗生素具有同等强吸附能力,本文侧重介绍土壤无机矿物对抗生素的吸附机理,从无机矿物表面特性(如S—OH)和结构组成(如2∶1型、1∶1型),以及抗生素母体携带官能团的量和种类(如—OH、—CHO、—COOH)等方面来阐述无机矿物对抗生素的吸附机理,认为离子交换与亲水作用对无机矿物吸附抗生素起主导作用。还讨论了环境中pH值、离子强度和溶解有机质对无机矿物吸附抗生素的影响。并比较研究者在观点上异同点,对将来研究方向提几点建议。 相似文献
127.
Bacterial pathogens that are multi-drug resistant compromise the effectiveness of treatment when they are the causative agents of infectious disease. These multi-drug resistance mechanisms allow bacteria to survive in the presence of clinically useful antimicrobial agents, thus reducing the efficacy of chemotherapy towards infectious disease. Importantly, active multi-drug efflux is a major mechanism for bacterial pathogen drug resistance. Therefore, because of their overwhelming presence in bacterial pathogens, these active multi-drug efflux mechanisms remain a major area of intense study, so that ultimately measures may be discovered to inhibit these active multi-drug efflux pumps. 相似文献
128.
129.
简介了纯海洋动物再生纤维—壳聚糖纤维的理化性质、生物学特性、抑菌机理以及调节人体皮肤微生态平衡的保健功能。重点阐述了由废弃虾、蟹壳为原料,生产纯壳聚糖纤维的关键技术和全程无毒化纺丝的工艺优点,纯壳聚糖纤维在医药、工业、纺织等领域的应用现状,以及实现原料国产化及纤维产业化发展。 相似文献
130.
两相厌氧系统处理乙酰螺旋霉素废水 总被引：5，自引：0，他引：5
两相厌氧系统处理抗生素废水的生产性应用表明 :当两相厌氧系统进水pH ,VFA ,COD ,BOD5分别为 5 4 6 ,1376mg/L ,85 97mg/L ,4 12 6mg/L ,产酸器 (厌氧折流板反应器 )的停留时间为 12h时 ,pH由5 4 6升高至 6 18,VFA由 1376mg/L升高至 32 81mg/L ,BOD5/COD由 0 4 8升高至 0 5 2 ;产甲烷器 (厌氧复合床反应器 )的停留时间为 39h时 ,COD和BOD5的去除率分别为 90 4 %和 94 5 % . 相似文献