The StepOne real-time polymerase chain reaction detection of Salmonella sp., Salmonella enterica ser. typhimurium and enteritidis in milk and meat

The aim of this study was to follow contamination of ready to eat milk and meat products with Salmonella spp. by using the StepOne real-time polymerase chain reaction (PCR). Classical microbiological methods for detection of foodborne bacteria involve the use of pre-enrichment and/or specific enrichment, following isolation of bacteria in solid media and the final confirmation by biochemical and/or serological tests. We used the PrepSEQ Rapid Spin Sample Preparation Kit for isolation of DNA and MicroSEQ? Salmonella spp. Detection Kit for pursuance of the real-time PCR (Applied Biosystems). In samples without incubation we detected strain of Salmonella sp. in 5 out of 25 samples (swabs), as well as in the internal positive control (IPC), which was positive in all samples. This StepOne real-time PCR assay is extremely useful for any laboratory equipped by real-time PCR. It is a fast, reproducible, simple, specific and sensitive way to detect nucleic acids, which could be used in clinical diagnostic tests in the future. Our results indicated that real-time PCR assay developed in this study could sensitively detect Salmonella spp. in ready-to-eat food. This could prevent infection caused by Salmonella, and also could benefit food manufacturing companies by extending their product's shelf-life as well as saving the cost of warehousing their food products while awaiting pathogen testing results.     

Major histocompatibility complex class II variation in bottlenose dolphin from Adriatic Sea: inferences about the extent of balancing selection

The bottlenose dolphin (Tursiops truncatus) is the most common cetacean species worldwide and the only marine mammal species resident in the Croatian part of the Adriatic Sea. To gain insight into genetic diversity of bottlenose dolphins at adaptively important loci relevant to conservation, we analysed the polymorphism of major histocompatibility complex (MHC) genes, which play a key role in pathogen confrontation and clearance. Specifically, we examined the diversity of MHC class II DRA, DQA and DQB alleles in 50 bottlenose dolphins from the Adriatic Sea collected between 1997 and 2011 and in 12 animals from other Mediterranean locations. Notable variation in DQA, DQB and three-locus haplotypes was found, with all 10 DQA and 12 DQB alleles encoding unique protein products. Analysis of the ratio of non-synonymous to synonymous substitution rates suggests that positive selection acts at both highly variable loci. Phylogenetic analyses revealed trans-species polymorphism at the DQB locus, strongly indicating the influence of balancing selection in the long term. In fact, the balancing selection observed in bottlenose dolphins is higher than that reported for most other cetaceans and comparable to that seen in terrestrial mammals.     

Changing forest conservation and management paradigms: traditional ecological knowledge systems and sustainable forestry: Perspectives from Chile and India

This paper first explores the shift now occurring in the science that provides the theoretical basis for forest conservation and management. The paper then presents the concepts of traditional ecological knowledge and traditional management systems and practise to provide background for two case studies that examine traditional knowledge and forest management practices of tribal communities in the Sariska region (Rajasthan, India) and of the indigenous Mapuche Pewenhce communities in the Andean mountains of southern Patagonia in Chile, underlining the special relationship these tribal and indigenous communities maintain with the forest and their usefulness in community-based native forest conservation. These examples of traditional ecological knowledge and traditional management systems suggest that it is important to focus on managing ecological processes, instead of products, and to use integrated ecosystem management. Recommendations to move forest management paradigms beyond the current view of ‘timber’ or ‘reserves’ and toward one of truly integrated use that adapt conservation approaches to local cultural representations of the environment are made.     

纳米铜颗粒的种间毒性关系

纳米颗粒的种间毒性关系尚无明确结论,因此很难判断纳米颗粒对未进行毒性测试的物种的风险如何。本文作者将5种水蚤(Daphnia magna, Daphnia pulex, Daphnia galeata, Ceriodaphnia dubia, Chydorus sphaericus)暴露于4种不同粒径的纳米铜颗粒(CuNPs)和1种亚微米铜颗粒的悬浊液中,考察物种的形态特征与CuNPs急性毒性的关系。结果显示,杆状的CuNPs比球状的CuNPs毒性更低。纳米铜颗粒与溶出铜离子均对CuNPs的毒性有贡献,其中,当新生蚤的体长、体表面积和身体体积更小时,5种悬浊液中颗粒的毒性更大。5种蚤的身体体积与5种CuNPs的毒性显著相关(r_adj²>0.51, p < 0.001),78-nm CuNPs与蚤身体体积的相关性最好 (r_adj²?=?0.95, p < 0.001)。这个研究可以为纳米颗粒对有相似外形特征的物种进行毒性种间外推提供线索。
精选自Lan Song, Martina G. Vijver, Geert R. de Snoo and Willie J.G.M. Peijnenburg. Assessing toxicity of copper nanoparticles across five cladoceran species. Environmental Toxicology and Chemistry: Volume 34, Issue 8, pages 1744–1750, August 2015. DOI: 10.1002/etc.3000
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3000/full     

Influence of long-term consumption of bitter apricot seeds on risk factors for cardiovascular diseases

The present study was designed to reveal whether long-term consumption of bitter apricot seeds causes changes in lipid profile and other risk factors for cardiovascular diseases. The study group consisted of 12 healthy adult volunteers (5 females and 7 males). The average age of women was 41.60 ± 11.28 years and the average age of men was 36.71 ± 13.70 years. Volunteers consumed 60 mg kg^?1 of body weight of bitter apricot seeds divided into 8–12 doses daily for 12 weeks. Volunteers were recruited from the general population of Slovak Republic. After 12 weeks, mean body weight of the participants increased from 77.34 to 78.22 kg (P > 0.05). The average total cholesterol levels decreased from 4.86 mmol L^?1 at the beginning of the study to 4.44 mmol L^?1 at the end of the study (P < 0.05). We did not observe any significant increase in high-density cholesterol (from 1.55 to 1.60 mmol L^?1). The average low-density cholesterol levels decreased from 2.93 mmol L^?1 at the beginning of the study to 2.31 mmol L^?1 at the end of the study (P < 0.001). Concentration of triglycerides increased significantly over the 12-week intervention period from 0.84 to 1.17 mmol L^?1. After the intervention, the high-sensitivity C-reactive protein level decreased from 1.92 to 1.23 mg L^?1, but results were non-significant (P > 0.05). Creatine kinase serum levels increased from 2.31 to 2.77 mg L^?1 (P > 0.05) over the 12-week intervention period. The results suggest that regular intake of bitter apricot seeds may be considered potentially useful for prevention of cardiovascular diseases.     

Spatial and temporal analysis of pesticides concentrations in surface water: pesticides atlas

Dutch water boards have a well-established program for monitoring pesticide contamination of surface waters. These monitoring data have been processed into a graphic format accessible online and designed to provide insight into pesticide presence in Dutch surface waters and trends over time: the Pesticides Atlas (http://www.pesticidesatlas.nl). With this tool one can easily get maps of where a pesticide is being measured and where it might possibly constitute an environmental problem over the years. Presently, results of the periods 1997/1998 until 2005/2006 are available at the level of individual active ingredients. At a national level, the percentage of pesticides concentrations that exceed the maximum tolerable risk has declined 30% to 38% over the years 2003/2004 compared with 1997/1998. This means that surface water quality in the Netherlands has improved with respect to pesticides, however there are still many locations at which the measured concentrations exceed the environmental quality standards. The results on linking land use to pesticides concentrations were shown to assist in optimization of monitoring programs. By developing the present Internet tool, many new opportunities for environmental risk assessment and risk management were identified, e.g. optimization of monitoring strategies and communication to policymakers.     

Adsorptive micellar flocculation as an efficient method for processing soil extracts containing both surfactant and polychlorinated biphenyls: practical demonstration.

The main purpose of the paper is to share the results and experience from processing soil extracts containing a high concentration of both anionic surfactant and polychlorinated biphenyls (PCBs) by use of method the called adsorptive micellar flocculation. The method is similar to coagulation, but the mechanism is more complicated. The flocculants examined in the laboratory section involved ferric chloride, aluminium chloride, ferric sulfate, and aluminum sulfate. It was observed that ferric chloride provides the best PCB removal efficiency from the extract. Subsequently, two extracts obtained from the pilot-scale demonstration of the PCBs leaching from the soils by the surfactant solution were processed by this method. The volume of the extracts processed was several hundred liters. The method proved it can remove PCBs from all extracts with a very high efficiency (greater than 99.99%). The residual PCB concentrations in solution were less than 1 microg/L.     

Uptake kinetics of metals by the earthworm Eisenia fetida exposed to field-contaminated soils

It is well known that earthworms can accumulate metals. However, most accumulation studies focus on Cd-, Cu-, Pb- or Zn-amended soils, additionally few studies consider accumulation kinetics. Here we model the accumulation kinetics of 18 elements by Eisenia fetida, exposed to 8 metal-contaminated and 2 uncontaminated soils. Tissue metal concentration was determined after 3, 7, 14, 21, 28 and 42 days. Metal elimination rate was important in determining time to reach steady-state tissue metal concentration. Uptake flux to elimination rate ratios showed less variation and lower values for essential than for non-essential metals. In theory kinetic rate constants are dependent only on species and metal. Therefore it should be possible to predict steady-state tissue metal concentrations on the basis of very few measurements using the rate constants. However, our experiments show that it is difficult to extrapolate the accumulation kinetic constants derived using one soil to another.     

Aporrectodea caliginosa, a suitable earthworm species for field based genotoxicity assessment?

There is a growing interest for the application of biomakers to field-collected earthworms. Therefore we have evaluated the usability of native populations of endogeic, widely distributed earthworm Aporrectodea caliginosa in the assessment of soil genotoxicity using the Comet assay. Validation of the Comet assay on earthworm coelomocytes has been established using commercially available Eisenia fetida exposed to copper, cadmium, and pentachlorophenol, along with A. caliginosa exposed to copper in a filter paper contact test. Neutral red retention time (NRRT) assay was conducted on copper exposed and field-collected earthworms. Significant DNA and lysosomal damage was measured using Comet and NRRT assays in native populations of A. caliginosa sampled from the polluted soils in the urban area in comparison to the earthworms from the reference site. The results of this study confirm the employment of A. caliginosa as a suitable species for the in situ soil toxicity and genotoxicity field surveys.