Ethyl acetate, chloroform, butanol, and methanol extracts from the aerial part of Peganum harmala were tested for antibacterial, antioxidant, and antiviral activities. The antibacterial activity was evaluated by the determination of minimum inhibitory concentration (MIC) using the solid medium technique. Oxacillin, amoxicillin, ticarcillin, cefotaxim, and amphotericin were used as control agents. The antiviral activity was evaluated against human cytomegalovirus (HCMV) strain AD-169 (ATCC Ref. VR 538) and Coxsackie B virus type 3 (CoxB-3) using a cytopathic effect (CPE) reduction assay. The antioxidant activity was evaluated using two tests: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical scavenging and ammonium thiocyanate methods. Among tested extracts; the chloroform extract displayed a higher antibacterial activity against Gram-positive than Gram-negative bacteria. The butanol extract demonstrated the highest antioxidant activity. The methanol extract showed significant antiviral activity against CoxB-3 virus. The chloroform extract may be an important source of bactericidal compounds against Gram-positive bacteria. 相似文献
The prevalence of older drivers’ engagement in distracting activities while driving is largely unexplored. Face-to-face interviews were conducted in the city of Braunschweig, Germany, comparing a sample of older drivers (n = 205) to a group of middle-aged drivers (n = 209). The drivers were interviewed on their engagement in distracting activities during the last half an hour of their driving trip, including the frequency and duration of these activities, their perception of the risk associated with these distracting activities and the role of these activities in at-fault crashes. Middle-aged drivers were significantly more likely to engage in certain distracting activities than older drivers. With regard to the duration of interactions with the passengers older drivers were significantly more talkative than middle-aged drivers. Middle-aged drivers rated most of the distracting activities as significantly less dangerous than older drivers. Distraction-related crashes are not a special problem of older drivers but seem to be very comparable to the middle-aged drivers. It is concluded that older drivers’ reluctance to engage in distracting tasks while driving is either a process of self-regulation or their age-related prudence. The study is the first to gather knowledge about distraction in German older drivers. Although older drivers are not currently overrepresented in distraction-related crashes, it is important to note that future cohorts of older drivers might differ in the way they engage with vehicles and technologies, which in turn may influence their driving patterns and willingness to engage in potentially distracting activities. 相似文献
This research focuses on the heavy metal contamination of the paddy soils and rice from Kočani Field (eastern Macedonia) resulting
from irrigation by riverine water impacted by past and present base-metal mining activities and acid mine drainage. Very high
concentrations of As, Cd, Cu, Pb and Zn were found in the paddy soils (47.6, 6.4, 99, 983 and 1,245 μg g−1) and the rice (0.53, 0.31, 5.8, 0.5 and 67 μg g−1) in the western part of Kočani Field, close to the Zletovska River, which drains the mining facilities of the Pb–Zn mine
in Zletovo. In terms of health risk, the observed highest concentrations of these elements in the rice could have an effect
on human health and should be the subject of further investigations. 相似文献
Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant and has been found to be the predominant perfluorinated chemicals (PFCs) in the environment. In the present study, planarian Dugesia japonica is employed to investigate the toxicity of this compound. The behavioural activity, survival, regeneration and antioxidant enzyme activities of the D. japonica exposed to PFOS were investigated. The results showed that the planarian D. japonica is very sensitive to low concentration pollutants including PFOS and suitable for toxicological bioassays. PFOS has severe toxicity in inducing oxidative stress, regeneration and development toxicity in planarians. The toxicity is indicated by reduced planarian locomotor velocity (pLMV), reduced appearance of auricles in regenerating animals, changed in antioxidant enzyme SOD and CAT activities. The information presented in this study will help elucidating the PFOS-induced toxicity in aquatic organisms. 相似文献
Under the Stockholm Convention on Persistent Organic Pollutants (POPs), China is required not only to reduce polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) but also unintentionally produced polychlorinated biphenyls (PCB), hexachlorobenzene (HCB) and pentachlorobenzene (PeCBz). A baseline of the sources in China that generate these unintentional POPs is needed for both research and regulation purposes. In this paper, we have compiled production data of potential sources in China and assessed them in five-year intervals from 2000 to 2015. Most of these activities experienced changes from rapid growth to slow growth. Measured data for PCB, HCB and PeCBz in samples collected from potential sources in China were reviewed. Most information was associated to thermal processes with high potential of emission, including waste incineration and ferrous and non-ferrous metal production. In addition, high levels of PCB, HCB and PeCBz were found as impurities in a few chlorinated products or as by-products in solvent production, which suggested organochlorine industry might be important sources. Finally, based on the studies reviewed, recommendations for future actions in research and policy as well as a few regulatory issues in China are discussed.