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21.
Context/objective: Cell lines used to study the role of the G protein-coupled receptor 30 (GPR30) or G protein-coupled estrogen receptor (GPER) as a mediator of estrogen responses have yielded conflicting results. This work identified a simple assay to predict cell line competence for pharmacological studies of GPR30.

Materials and methods: The phosphorylation or expression levels of ERK1/2, Akt, c-Fos and eNOS were evaluated to assess GPR30 activation in response to known agonists (17β-estradiol and G-1) in MCF-7 and T-47D breast cancer cell lines and in bovine aortic endothelial cells. GPR30 expression was analyzed by qRT-PCR and Western blot with two distinct antibodies directed at its carboxy and amino terminals.

Results: None of the agonists, at any of the concentrations tested, activated any of those target proteins. Additional experiments excluded the disruption of the signaling pathway, interference of phenol red in the culture medium and constitutive proteasome degradation of GPR30 as possible causes for the lack of response of the three cell lines. Analysis of receptor expression showed the absence of clearly detectable GPR30 species of 44 and 50–55?kDa previously identified in cell lines that respond to 17β-estradiol and G-1.

Discussion and conclusion: Cells that do not express the 44 and 50–55?kDa species do not respond to GPR30 agonists. Thus, the presence or absence of these GPR30 species is a simple and rapid manner to determine whether a given cell line is suitable for pharmacological or molecular studies of GPR30 modulation.  相似文献   
22.
Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX).  相似文献   
23.
Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories.  相似文献   
24.
Three wheat samples collected in 1987 in Central Poland and naturally infected withFusarium spp were analyzed for the presence ofFusarium spp andFusarium toxins. Heads were separated into three fractions: kernels with visibleFusarium damage, healthy looking kernels, and chaff + rachis. The samples contained deoxynivalenol (2.0 – 40.0μg/g), nivalenol (O.O1μg/g), 4,7-dideoxynivalenol (0.10 – 0.15μg/g). 15-acetyldeoxynivalenol (0.10–2.00 μg/g), 3-acetyldeoxynivalenol (O/1Oμg/g), and zearalenone (0.01–2.00μg/g). This is the first report about 15 - acetyldeoxynivalenol in European wheat and the co-occurrence of 3 - acetyldeoxynivalenol and 15-acetyldeoxynivalenol in the same sample of contaminated cereals.  相似文献   
25.
Loss, fragmentation and decreasing quality of habitats have been proposed as major threats to biodiversity world‐wide, but relatively little is known about biodiversity responses to multiple pressures, particularly at very large spatial scales. We evaluated the relative contributions of four landscape variables (habitat cover, diversity, fragmentation and productivity) in determining different components of avian diversity across Europe. We sampled breeding birds in multiple 1‐km2 landscapes, from high forest cover to intensive agricultural land, in eight countries during 2001?2002. We predicted that the total diversity would peak at intermediate levels of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; forest and open‐habitat specialists would show threshold conditions along gradients of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; resident species would be more strongly impacted by forest cover and fragmentation than migratory species; and generalists and urban species would show weak responses. Measures of total diversity did not peak at intermediate levels of forest cover or fragmentation. Rarefaction‐standardized species richness decreased marginally and linearly with increasing forest cover and increased non‐linearly with productivity, whereas all measures increased linearly with increasing fragmentation and landscape diversity. Forest and open‐habitat specialists responded approximately linearly to forest cover and also weakly to habitat diversity, fragmentation and productivity. Generalists and urban species responded weakly to the landscape variables, but some groups responded non‐linearly to productivity and marginally to habitat diversity. Resident species were not consistently more sensitive than migratory species to any of the landscape variables. These findings are relevant to landscapes with relatively long histories of human land‐use, and they highlight that habitat loss, fragmentation and habitat‐type diversity must all be considered in land‐use planning and landscape modeling of avian communities.  相似文献   
26.
An assay system was developed for the adult silverleaf whitefly, Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae). This practical device was constructed from standard disposable laboratory materials. Whiteflies were harvested directly from the leaf and into a collection vial by vacuum aspiration, minimizing physical damage to the insect. Insects were fed through a cellulose mixed-ester membrane on a diet of 20–27% sucrose alone or sucrose in an extract of zucchini (Curcurbita moschata Duchense). Mortality and honeydew production were scored. At 22–25°C and 50–55% relative humidity, control mortality generally remained at or below 15% during a 48 h assay period. The bioassay system was first tested using the insecticide, Imidacloprid, then used to screen a number of natural products with potential insecticidal activity against the whitefly. Destruxins extracted from the entomopathogenic fungus, Metarhizium anisopliae, and the natural insecticide/nematicide, Ivermectin, as well as bee venom and two of its components, melittin and phospholipase A2, were found to be toxic to B. argentifolii. Five lectins, Bacillus thuringiensis toxins, gossypol, an extract of Paeciliomyces fumosoroseus, wasp and scorpion venom, and a trypsin inhibitor were not found to be insecticidal to adult B. argentifolii.  相似文献   
27.

Background

Viewed through the micro focus of an interpretive lens, medical anthropology remains mystified because interpretivist explanations seriously downplay the given context in which individual health seeking-behaviours occur. This paper draws upon both the interpretivist and political economy perspectives to reflect on the ethno medical practices within the Korean-Australian community in Sydney.

Methods

We draw on research data collected between 1995 and 1997 for an earlier study of the use of biomedical and traditional medicine by Korean-Australians in Sydney. A total of 120 interviews were conducted with a range of participants, including biomedical doctors, traditional health professionals, Korean community leaders and Korean migrants representing a range of socio-economic backgrounds and migration patterns.

Results and Discussion

First, the paper highlights the extent to which the social location of migrants in a host society alters or restructures their initial cultural practices they bring with them. Second, taking hanbang medicine in the Korean-Australian community as an illustrative case, the paper explores the transformation of the dominant biomedicine in Australia as a result of the influx of ethnomedicine in the era of global capitalism and global movement.

Conclusion

In seeking to explain the popularity and supply of alternative health care, it is important to go beyond the culture of each kind of health care itself and to take into consideration the changes occurring at societal, national and global levels as well as consequential individual response to the changes. New social conditions influence the choice of health care methods, including herbal/alternative medicine, health foods and what are often called New Age therapies.  相似文献   
28.
In practical bioremediation of petroleum pollution, treatment systems often use soil, sand, and other aquifer porous media besides water solutions. The distribution of the microbial cell also plays an important role in the whole process of bioremediation; therefore, the adhesion ability of cells to porous media is one of the key factors influencing the efficiency of treatment. The probable modes of hydrocarbon uptake in cells of Candida were studied based on data for cell hydrophobicity, emulsifying activity, surface tension, and interfacial tension of the cell-free culture medium. Six Candida strains were cultivated in insoluble and soluble substrates for 144 h, including n-hexadecane, soybean oil, ground-nut oil refinery residue, corn steep liquor, and glucose. The results obtained showed the potential of yeasts for application in the removal of hydrophobic compounds. Depending the strain and substrate used the adhesion ability of yeast cells and the production of surfactants and emulsifiers can take place simultaneously, thus increasing the efficiency of bioremediation treatment of petroleum pollution. The application of crude biosurfactants separated from the yeast cells was also demonstrated by tests of removal of petroleum and the derivate motor oil adsorbed in sand samples. Biosurfactants produced in low-cost medium were able to remove 90% of the hydrophobic contaminants.  相似文献   
29.
Galicia (NW Spain) is a region with a high number of freshwater endemics, and probably the best preserved area concerning fish populations in the Iberian Peninsula, where records of non-indigenous freshwater species are recent when compared to the rest of the Peninsula. Detailed analysis of introductions of those species with records after 1900 present in both areas shows that delays were up to 100 years for species introduced on the Iberian Peninsula at the beginning of the twentieth century, but the tendency adjust to a decreasing linear regression, with species introduced after 1995 being almost immediately present in Galicia. We underline the outstanding role of aquarium trade on these results. Analysis of temporal trends highlights several periods with numerous introductions, and shows a different trend in the last decade depending on the group of organisms, with a clear deceleration in introduction rates of vertebrates, but a continuous growing trend for invertebrates. Recent educational programs might be responsible for the reduction in the inflow of vertebrates, but there is still a need for the control of less conspicuous but equally harmful invertebrates and plants, as it will take longer to make both stakeholders and public aware of their detrimental effects on their new habitats.  相似文献   
30.

Background  

It is a well-known phenomenon that some patients with acute left or right hemisphere stroke show a deviation of the eyes (Prévost's sign) and head to one side. Here we investigated whether both right- and left-sided brain lesions may cause this deviation. Moreover, we studied the relationship between this phenomenon and spatial neglect. In contrast to previous studies, we determined not only the discrete presence or absence of eye deviation with the naked eye through clinical inspection, but actually measured the extent of horizontal eye-in-head and head-on-trunk deviation. In further contrast, measurements were performed early after stroke onset (1.5 days on average).  相似文献   
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