What do patients want to know about their medicines, and what do doctors want to tell them?: a comparative study

A two phase study is reported. In the first phase, we asked a number of doctors to rate a list of information categories (identified by Berry, Gillie and Banbury 1995) in terms of how important they felt it was for the items to be included in an explanation to a patient about a drug prescription. In the second phase, we presented a large sample of people with a scenario about visiting their doctor and being prescribed medication, together with an explanation about the prescription which was said to be provided by the doctor. Four different explanations were compared, which were either based on what people in our earlier study wanted to know about drug prescriptions or on what the doctors thought it was important lo tell them. We also manipulated whether or not the explanations conveyed negative information (e.g. about the possible side effects of the medication). The results showed that people 'preferred' the explanations based on what the participants in the earlier study wanted to know about their medicines, rather than those based on what the doctors thought they should be told. They also 'preferred' the explanations that did not convey negative information, rather than those that did convey some negative information. In addition, the inclusion of negative information affected ratings of likely compliance with the prescribed medication.

A comparative study of the effects of metal contamination on collembola in the field and in the laboratory

We examined the species diversity and abundance of Collembola at 32 sampling points along a gradient of metal contamination in a rough grassland site ( Wolverhampton, England), formerly used for the disposal of metal-rich smelting waste. Differences in the concentrations of Cd, Cu, Pb and Zn between the least and most contaminated part of the 35 metre transect were more than one order of magnitude. A gradient of Zn concentrations from 597 to 9080 mug g(-1) dry soil was found. A comparison between field concentrations of the four metals and previous studies on their relative toxicities to Collembola, suggested that Zn is likely to be responsible for any ecotoxicological effects on springtails at this site. Euedaphic ( soil dwelling) Collembola were extracted by placing soil cores into Tullgren funnels and epedaphic ( surface dwelling) species were sampled using pitfall traps. There was no obvious relationship between the total abundance, or a range of commonly used diversity indices, and Zn levels in soils. However, individual species showed considerable differences in abundance. Metal "tolerant'' (e.g., Ceratophysella denticulata) and metal "sensitive'' (e.g., Cryptopygus thermophilus) species could be identified. Epedaphic species appeared to be influenced less by metal contamination than euedaphic species. This difference is probably due to the higher mobility and lower contact with the soil pore water of epedaphic springtails in comparison to euedaphic Collembola. In an experiment exposing the standard test springtail, Folsomia candida, to soils from all 32 sampling points, adult survival and reproduction showed small but significant negative relationships with total Zn concentrations. Nevertheless, juveniles were still produced from eggs laid by females in the most contaminated soils with 9080 mug g(-1) Zn. Folsomia candida is much more sensitive to equivalent concentrations of Zn in the standard OECD soil. Thus, care should be taken in extrapolating the results of laboratory toxicity tests on metals in OECD soil to field soils, in which, the biological availability of contaminants is likely to be lower. Our studies have shown the importance of ecotoxicological effects at the species level. Although there may be no differences in overall abundance, sensitive species that are numerous in contaminated sites, and which may play important roles in decomposition("keystone species'') can be greatly reduced in numbers by pollution.

A comparative study on the effectiveness of laboratory bioassays of entomopathogenic nematodes against desert locust nymphs Schistocerca gregaria (Acrididae:Orthoptera)

Entomopathogenic nematodes, Steinernema carpocapsae, S. feltiae (Steinernematids) Heterorhabditis indica and H. bacteriophora (Heterorhabditids) were studied to control nymphs of desert locust Schistocerca gregaria. Results of all experiments showed a significant difference in mortality percentage among all isolates. All nematodes were found more effective when exposure time was increased up to 10 days. On the other hand, both Heterorhabditids caused maximum mortality as compared to Steinernematids at 30 degree C. When different moisture levels were tested in the sand arena, a medium level of moisture (1%) caused maximum insect mortality in all isolates. However, highest concentration of each isolate (200 IJs per ml) proved to be most appropriate for maximum insect death. Similarly, both Heterorhabditis nematodes when orally applied to insects killed maximum nymphs as compared to other two Steinernematids. A similar response was observed in infectivity test when maximum percentage of IJs of both isolates of Heterorhabditis successfully penetrated into the body of locust nymphs. This research suggests some useful basic findings in developing biocides with suitable virulent of entomopathogenic nematode for controlling nymphs of desert locust.

Comparative study of oestrogenic properties of eight phytoestrogens in MCF7 human breast cancer cells

Previous studies have compared the oestrogenic properties of phytoestrogens in a wide variety of disparate assays. Since not all phytoestrogens have been tested in each assay, this makes inter-study comparisons and ranking oestrogenic potency difficult. In this report, we have compared the oestrogen agonist and antagonist activity of eight phytoestrogens (genistein, daidzein, equol, miroestrol, deoxymiroestrol, 8-prenylnaringenin, coumestrol and resveratrol) in a range of assays all based within the same receptor and cellular context of the MCF7 human breast cancer cell line. The relative binding of each phytoestrogen to oestrogen receptor (ER) of MCF7 cytosol was calculated from the molar excess needed for 50 % inhibition of [H-3]oestradiol binding (IC50), and was in the order coumestrol (35x)/8-prenylnaringenin (45 x)/deoxymiroestrol (50 x) > miroestrol (260x) > genistein (1000x) > equol (4000x) > daidzein (not achieved: 40 % inhibition at 10(4)-fold molar excess) > resveratrol (not achieved: 10 % inhibition at 10(5)-fold molar excess). For cell-based assays, the rank order of potency (estimated in terms of the concentration needed to achieve a response equivalent to 50 % of that found with 17 beta-oestradiol (IC50)) remained very similar for all the assays whether measuring ligand ability to induce a stably transfected oestrogen-responsive ERE-CAT reporter gene, cell growth in terms of proliferation rate after 7 days or cell growth in terms of saturation density after 14 days. The IC50 values for these three assays in order were for 17 beta-oestradiol (1 x 10-(11) M, 1 x 10-(11) M, 2 x 10(-11) M), and in rank order of potency for the phytoestrogens, deoxymiroestrol (1 x 10(-10) M, 3 x 10(-11) M, 2 x 10(-11) M) > miroestrol (3 x 10(-10) M, 2 x 10(-11) M, 8 x 10(-11) M) > 8-prenylnaringenin (1 x 10(-9) M, 3 x 10(-10) M, 3 x 10(-10) M) > cournestrol (3 x 10(-8) M, 2 x 10(-8) M, 3 x 10(-8) M) > genistein (4 x 10(-8) M, 2 x 10(-8) M, 1 x 10(-8) M)/equol (1 x 10(-7) M, 3 x 10(-8) M, 2 x 10(-8) M) > daidzein (3 x 10(-7) M, 2 x 10(-7) M, 4 x 10(-8) M) > resveratrol (4 x 10(-6) M, not achieved, not achieved). Despite using the same receptor context of the MCF7 cells, this rank order differed from that determined from receptor binding. The most marked difference was for cournestrol and 8-prenylnaringenin which both displayed a relatively potent ability to displace [3H]oestradiol from cytosolic ER compared with their much lower activity in the cell-based assays. Albeit at varying concentrations, seven of the eight phytoestrogens (all except resveratrol) gave similar maximal responses to that given by 17 beta-oestradiol in cell-based assays which makes them full oestrogen agonists. We found no evidence for any oestrogen antagonist action of any of these phytoestrogens at concentrations of up to 10(-6) M on either reporter gene induction or on stimulation of cell growth. (c) 2005 Elsevier Ltd. All rights reserved.

A comparative study of the effects of metal contamination on collembola in the field and in the laboratory

We examined the species diversity and abundance of Collembola at 32 sampling points along a gradient of metal contamination in a rough grassland site ( Wolverhampton, England), formerly used for the disposal of metal-rich smelting waste. Differences in the concentrations of Cd, Cu, Pb and Zn between the least and most contaminated part of the 35 metre transect were more than one order of magnitude. A gradient of Zn concentrations from 597 to 9080 mug g(-1) dry soil was found. A comparison between field concentrations of the four metals and previous studies on their relative toxicities to Collembola, suggested that Zn is likely to be responsible for any ecotoxicological effects on springtails at this site. Euedaphic ( soil dwelling) Collembola were extracted by placing soil cores into Tullgren funnels and epedaphic ( surface dwelling) species were sampled using pitfall traps. There was no obvious relationship between the total abundance, or a range of commonly used diversity indices, and Zn levels in soils. However, individual species showed considerable differences in abundance. Metal "tolerant'' (e.g., Ceratophysella denticulata) and metal "sensitive'' (e.g., Cryptopygus thermophilus) species could be identified. Epedaphic species appeared to be influenced less by metal contamination than euedaphic species. This difference is probably due to the higher mobility and lower contact with the soil pore water of epedaphic springtails in comparison to euedaphic Collembola. In an experiment exposing the standard test springtail, Folsomia candida, to soils from all 32 sampling points, adult survival and reproduction showed small but significant negative relationships with total Zn concentrations. Nevertheless, juveniles were still produced from eggs laid by females in the most contaminated soils with 9080 mug g(-1) Zn. Folsomia candida is much more sensitive to equivalent concentrations of Zn in the standard OECD soil. Thus, care should be taken in extrapolating the results of laboratory toxicity tests on metals in OECD soil to field soils, in which, the biological availability of contaminants is likely to be lower. Our studies have shown the importance of ecotoxicological effects at the species level. Although there may be no differences in overall abundance, sensitive species that are numerous in contaminated sites, and which may play important roles in decomposition("keystone species'') can be greatly reduced in numbers by pollution.

A comparative study on the relationship between acetyl cholinesterase activity and acute toxicity in Daphnia magna exposed to anticholinesterase insecticides

Acetylcholinesterase (AChE) activity was measured in Daphnia magna that had been exposed to four organophosphates (OPs; parathion, chlorpyrifos, malathion, and acephate) and one carbamate (propoxur) for 48 h. These results were related to acute toxicity (median effective concentration [EC50] for immobility). For the four OPs, the EC50s were 7.03 pM, 3.17 pM, 10.56 pM, and 309.82 muM, respectively. The EC50 for propoxur was 449.90 pM. Reduction in AChE activity was directly related to an increase in immobility in all chemicals tested. However, the ratio between the EC50 and the AChE median inhibiting concentration ranged from 0.31 to 0.90. A 50% reduction in AChE activity generally was associated with detrimental effects on mobility. However, for acephate, high levels of AChE inhibition (70%) were observed in very low concentrations and were not associated with immobility. In addition, increasing the concentration of acephate further had a slight negative effect oil AChE activity but a Strong detrimental effect on mobility. Binding sites other than AChE possibly are involved in acephate toxicity to D. magna. Our findings demonstrate different associations between AChE inhibition and toxicity when different chemicals are compared. Therefore, the value of using AChE activity as a biomarker in D. magna will be dependent on the chemical tested.