A Preliminary Human Health Risk Assessment of Organochlorine Pesticide Residues Associated with Aquatic Organisms from the Rangsit Agricultural Area,Central Thailand

Food consumption is one of the main routes of human exposure to organochlorine pesticide residues (OCPRs). To assess the potential health risks associated with OCPRs contaminants due to freshwater organism consumption, a number of vegetables, prawn, snail, and fish were collected from Khlong 7 (canal), Rangsit agricultural area, Pathum-Thani Province, Thailand. The samples were extracted using a multiresidue extraction method and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb) levels. Based on a plausible worst-case scenario, the local population could be at risk for cancer due to consumption of fish contaminated by α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, dieldrin, DDD, DDE, and DDT. Likewise, individuals may be at risk from consumption of Lanchester's freshwater prawn Macrobrachium lanchesteri, freshwater snail Filopaludina mertensi, swamp morning-glory Ipomomea aquatica, neptunia Neptunia oleracea, and water lily Nymphaea lotus because these species all contained elevated concentrations of α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, and dieldrin.     

Flood Risk Analysis Based on Information Diffusion Theory

Due to the fact that the flood data series of small drainage basins is relatively short, available data are often not sufficient for flood risk analysis. This presents the problem of risk analysis using very small data samples. One method that can be applied is to regard the available small samples as fuzzy information and optimize them using information diffusion technology to yield analytical results with greater reliability. In this article a risk analysis method based on information diffusion theory is applied to create a new flood risk analysis model. Application of the model is illustrated taking the Jinhuajiang and Qujiang drainage basins as examples. This is a new attempt at applying information diffusion theory in flood risk analysis. Computations based on this analytical flood risk model can yield an estimated flood damage value that is relatively accurate. This study indicates that the aforementioned model exhibits fairly stable analytical results, even when using a small set of sample data. The results also indicate that information diffusion technology is highly capable of extracting useful information and therefore improves system recognition accuracy. This method can be easily applied and the analytical results produced are easy to understand. Results are accurate enough to act as a guide in disaster situations.     

Shifting the balance between foraging and predator avoidance: the importance of food distribution for a schooling pelagic forager

It is widely held that when predator avoidance conflicts with other activities, such as feeding, avoidance of predators often takes precedence. In this study, we examine how predation risk and food distribution interact to influence the schooling behavior and swimming speed of foraging juvenile walleye pollock, Theragra chalcogramma. Fish were acclimated to either spatially and temporally clumped, or spatially and temporally dispersed food for 3 weeks. Fish were then monitored while feeding in the absence and presence of predatory sablefish, Anoplopoma fimbria. Fish foraging for clumped food swam rapidly in a loose school when predators were absent, but swam more slowly and adopted more cohesive schooling in the presence of predators, trading-off foraging opportunity for decreased vulnerability to predators. Fish foraging for dispersed food swam about slowly and did not engage in cohesive schooling in either the absence or presence of predators. These fish accepted greater predation risk in order to continue foraging, suggesting that the cost of schooling, in terms of decreased foraging opportunity, was greater when food was dispersed than when it was clumped. This lower responsiveness to predators among fish receiving dispersed food demonstrates that predator avoidance does not always take precedence over other activities, but rather, that a balance is maintained between predator avoidance and feeding, which shifts as food distribution changes.     

When the tail can't wag the dog: the implications of CNS-intrinsic initiation of neuroinflammation

The CNS (central nervous system) is unquestionably the central organ that regulates directly or indirectly all physiological systems in the mammalian body. Yet, when considering the defence of the CNS from pathogens, the CNS has often been considered passive and subservient to the pro-inflammatory responses of the immune system. In this view, neuroinflammatory disorders are examples of when the tail (the immune system) wags the dog (the CNS) to the detriment of an individual''s function and survival.     

The significance of mycotoxins in the framework of assessing workplace related risks

Mycotoxins are fungal metabolite which may in some cases exhibit a high health hazard potential. Mycotoxins can show carcinogenic, mutagenic, toxic, teratogenic or immunotoxic effects. Mycotoxin exposure in the workplace may occur through inhalation and skin contact,e.g. during occupational handling of organic matter such as livestock feed, food products, or waste. Various studies suggest that both acute and chronic effects can occur, depending at least on the exposure level. The magnitude of the potential health risks associated with a respiratory or dermal intake of mycotoxins has largely remained unclear to date. However, according to the directive 2000/54/EC on biological agents and the corresponding German Biological Agents Ordinance, employers are also required to consider the potential hazards posed by toxic effects of biological agents when assessing workplace risks. The aim of this article, therefore, is to present some basis information that should facilitate an evaluation of the significance of mycotoxins in the context of assessing workplace risks. It also provides suggestions for occupational health and safety measures.     

Pulmonary neuroendocrine cells sense succinate to stimulate myoepithelial cell contraction

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In Pursuit of Safety: One-Hundred Years of Toxicological Risk Assessment

The publication in 1962 of Rachel Carson's Silent Spring marks the mid-point in a century that saw, in its first half, the emergence of public health concerns related to human exposures to chemicals, and, in its second half, the emergence of public policies to deal with those concerns. Those policies made it imperative that the scientific community come to grips with the problem of identifying exposure levels not likely to cause harm. This problem was not significantly discussed within the scientific community until the 1950s, and well-described methods for practical solutions to it did not appear until the 1970s. An important report from the National Academy of Sciences, published in 1983 (Risk Assessment in the Federal Government), provided an analysis of these emerging methods, and recommended a useful framework for the assessment and management of risk. This framework remains central to public health and regulatory decision-making. A high-level perspective is offered on events leading to and following the 1983 report. The article describes early thinking about chemical toxicity and the scientific path that thinking followed through the 20th century, and to the present.     

Retinoic Acid Improves a Hybridoma Culture in a Fructose-Based Medium by Up-Regulation of Fructose Incorporation via Retinoid Nuclear Receptors

Fructose was focused on as an alternative sugar source to glucose in a hybridoma culture medium because it decreases lactate production during cultivation, leading to cell and product stability. But, not all human hybridoma cell lines grew well in a fructose-based serum-free medium. We found that the addition of all-trans-retinoic acid to the fructose-based medium improved the growth and monoclonal antibody production of hybridoma cell lines by up-regulation of fructose incorporation that represented increased expression of the fructose transporter, GLUT5. Selective activation of retinoid nuclear receptor by synthetic ligands showed that both retinoic acid receptors and retinoid X receptors might be related to the improvement of the fructose-based hybridoma culture. This study might be applicable to cell cultures susceptible to lactate and pH changes as well as hybridoma cultures.     

Results of combined radiotherapy and hormonal treatment of prostate cancer patients with initial PSA value >40 ng/ml

AimTo evaluate the outcome of prostate cancer patients with initial PSA value >40 ng/ml.BackgroundThe outcome of prostate cancer patients with very high initial PSA value is not known and patients are frequently treated with palliative intent. We analyzed the outcome of radical combined hormonal treatment and radiotherapy in prostate cancer patients with initial PSA value >40 ng/ml.MethodsBetween January 2003 and December 2007 we treated, with curative intent, 56 patients with non-metastatic prostate cancer and initial PSA value >40 ng/ml. The treatment consisted of two months of neoadjuvant hormonal treatment (LHRH analog), radical radiotherapy (68–78 Gy, conformal technique) and an optional two-year adjuvant hormonal treatment.ResultsThe median time of follow up was 61 months. 5-Year overall survival was 90%. 5-Year biochemical disease free survival was 62%. T stage, Gleason score, PSA value, and radiotherapy dose did not significantly influence the outcome. Late genitourinal and gastrointestinal toxicity was acceptable.ConclusionRadical treatment in combination with hormonal treatment and radiotherapy can be recommended for this subgroup of prostate cancer patients with good performance status and life expectancy.