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21.
Brazilian wines of different regions and that commercially available in the city of Campinas, SP, were analysed for their contents of sulfites. Dietary exposure to sulfites from Brazilian wines was also assessed by combining sulfite levels determined analytically with three hypothetical scenarios of daily wine consumption: 150, 300, and 450 mL. In all samples, the concentration of sulfites was below the maximum permitted level (MPL) of 350 mg L−1 set in the Brazilian legislation with most samples (88%) containing residual sulfite below 150 mg L−1. The dietary exposure to sulfites from regular consumption of 150 mL of national white wines containing sulfites at the mean level of 122.0 mg L−1 covered 44% of the Acceptable Daily Intake (ADI) established by JECFA for these preservatives (0.7 mg kg−1 bw). For high regular consumption (450 mL per day) of white wines, the dietary exposure could reach 131% of the ADI. In the case of national red wines (SO2 mean level of 71.3 mg L−1) the dietary exposure was lower, ranging from 26 to 76% of the ADI for 150 and 450 mL of daily consumption, respectively. The present study indicates that although sulfite levels in national wines is usually below the MPL (mean of 98.5 mg L−1) a regular moderate consumption of 150 mL per day could lead to a dietary exposure of 15 mg of sulfites (0.25 mg kg−1 bw in a 60-kg adult), covering one-third of the ADI. A regular heavy consumption (450 mL per day) would cover the full ADI.  相似文献   
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23.
Since the beginning of computerization, it has been of interest whether there are differential effects on computer behavior, in particular in terms of computer access, computer use, and motivational variables, such as computer self-efficacy. The current research addresses the questions if the gender-related differences in this respect persist to the present day and if there is also a difference in actual performance characteristics. A sample of 48 university students (23 male) was administered a technology self-efficacy questionnaire, a survey on computer access, recorded a user diary, and turned in a computer task. Results show that the gender gap is closing as far as computer access and self-efficacy are concerned. Also, female and male students report comparable amounts of computer usage for their studies. User behavior appears to be gender-specific as males spend more time at the computer for personal purposes. There is also some evidence that male students outperform female students at a computer task (remastering of Power-Point slides). Conclusions for creating computer-based learning environments are discussed.  相似文献   
24.
So far, studies about targeted therapies and predictive biomarkers for vulva carcinomas are rare. The leucine zipper downregulated in cancer 1 gene (LDOC1) has been identified in various carcinomas as a tumor-relevant protein influencing patients’ survival and prognosis. Due to the lack of information about LDOC1 and its exact functionality, this study focuses on the expression of LDOC1 in vulvar carcinoma cells and its surrounding immune cells as well as its correlation to clinicopathological characteristics and prognosis. Additionally, a possible regulation of LDOC1 in vulvar cancer cell lines via the NF-κB signaling pathway was analyzed. Vulvar carcinoma sections of 157 patients were immunohistochemically stained and examined regarding LDOC1 expression by using the immunoreactive score (IRS). To characterize LDOC1-positively stained immune cell subpopulations, immunofluorescence double staining was performed. The effect of the NF-κB inhibitor C-DIM 12 (3,3′-[(4-chlorophenyl)methylene]bis[1 H-indole]) on vulvar cancer cell lines A431 and SW 954 was measured according to MTT and BrdU assays. Baseline expression levels of LDOC1 in the vulvar cancer cell lines A431 and SW 954 was analyzed by real-time PCR. LDOC1 was expressed by about 90% of the cancer cells in the cytoplasm and about half of the cells in the nucleus. Cytoplasmatic expression of LDOC1 was associated with decreased ten-year overall survival of the patient, whereas nuclear staining showed a negative association with disease-free survival. Infiltrating immune cells were mainly macrophages followed by regulatory T cells. Incubation with C-DIM 12 decreased the cell viability and proliferation of vulvar cancer cell line A431, but not of cell line SW 954. LDOC1 expression on mRNA level was twice as high in the cell line A431 compared to the cell line SW 954. Overexpression of LDOC1 was associated with unfavorable overall and disease-free survival. Tumor growth could be inhibited by C-DIM 12 in vitro if the expressed LDOC1 level was high enough.  相似文献   
25.
An analytical method for the determination of free 3-monochloropropane-1,2-diol (3-MCPD) in grilled meat using pressurized liquid extraction, derivatisation using phenylboronic acid, and gas chromatography/high resolution mass spectrometry was developed. The limit of quantification was 1???g/kg. Using this method, the contents of 3-MCPD in grilled steaks (collar) were analysed for different grilling conditions. Charcoal, an electric grill, and a gas grill were used for grilling collars. Further parameters investigated were the pre-treatment of meat (untreated, salted, marinated with oil or emulsion marinade), the use of aluminium grill trays, and a lid. For grilled steaks, contents of 3-MCPD in the range of <1 to 365???g/kg (median 16???g/kg) were detected. The highest contamination was found for a steak pre-treated with an oily marinade grilled on a charcoal grill with a closed lid. Consuming such a steak will exhaust the tolerable daily intake of 2???g/kg body weight for 3-MCPD to about 26?%.  相似文献   
26.

Scope

Red meat, a staple food of Western diets, can also induce IgE-mediated allergic reactions. Yet, apart from the heat-labile protein serum albumin and the carbohydrate α-Gal, the molecules causing allergic reactions to red meat remain unknown.

Methods and results

IgE reactivity profiles of beef-sensitized individuals are analyzed by IgE-immunoblotting with protein extracts from raw and cooked beef. Two IgE-reactive proteins are identified by peptide mass fingerprinting as myosinlight chain 1 (MYL1) and myosin light chain 3 (MYL3) in cooked beef extract and are designated Bos d 13 isoallergens. MYL1 and MYL3 are produced recombinantly in Escherichia coli. ELISAs proved their IgE reactivity and circular dichroism analysis showed that they represent folded molecules with remarkable thermal stability. In vitro gastrointestinal digestion experiments showed the higher stability of rMYL1 as compared to rMYL3. Exposure of a monolayer of Caco–2 cells to rMYL1 indicated that the molecule is able to cross intestinal epithelial cells without disturbing the integrity of the tight junctions, suggesting the sensitizing capacity of MYL1.

Conclusion

MYLs are identified as novel heat-stable bovine meat allergens.  相似文献   
27.
Fibroblasts are the main matrix producing cells of the dermis and are also strongly regulated by their matrix environment which can be used to improve and guide skin wound healing processes. Here, we systematically investigated the molecular effects on primary dermal fibroblasts in response to high-sulfated hyaluronan [HA] (hsHA) by quantitative proteomics. The comparison of non- and high-sulfated HA revealed regulation of 84 of more than 1,200 quantified proteins. Based on gene enrichment we found that sulfation of HA alters extracellular matrix remodeling. The collagen degrading enzymes cathepsin K, matrix metalloproteinases-2 and -14 were found to be down-regulated on hsHA. Additionally protein expression of thrombospondin-1, decorin, collagen types I and XII were reduced, whereas the expression of trophoblast glycoprotein and collagen type VI were slightly increased. This study demonstrates that global proteomics provides a valuable tool for revealing proteins involved in molecular effects of growth substrates for further material optimization.  相似文献   
28.
This report describes the development of a method for the determination and quantification of perfluoroalkyl substances (PFASs) in beer. A total of 93 beer samples were analyzed for the presence of PFASs by means of liquid chromatography tandem mass spectrometry. The results of this study have made it possible to calculate possible PFAS uptake via beer as well as the potential PFAS-related health risk as a result of beer consumption with regard to the tolerable daily intake (TDI) of perfluoro-n-octanoic acid (PFOA) (1,500 ng/kg bodyweight and day) and perfluorooctane sulfonate (PFOS) (150 ng/kg bodyweight and day). PFOS concentrations above the limit of quantification were detected in 50 % of the samples. The highest PFOS concentration detected in any of the beers was 18.4 ng/L, and the highest PFOA concentration was 56.9 ng/L. The calculated maximum uptake of both substances for which a TDI level exists were 2.44 ng/kg bodyweight/day for PFOA and 0.79 ng/kg bodyweight/day for PFOS assuming that an adult consumed his/her total daily liquid uptake exclusively by drinking 3 L of beer, equivalent to the maximum measured concentration (worst-case scenario). In regard to the model calculations made here, the maximum uptake of PFOA and PFOS via consumption of beer can be considered negligible at 0.85 % of the concentration that would be required to reach the TDI for PFOS and 0.16 % for PFOA.  相似文献   
29.
Old adults have to face many situations that require important decisions. In the present investigation, the authors examined the effects of aging on both decisions under ambiguity and decisions under risk. To this purpose, healthy young and old adults completed the Iowa Gambling Task (IGT) and the Probability-Associated Gambling task (PAG task). Old adults performed the PAG task as well as young adults, demonstrating ability to make decisions when full information about the problem situation, the options' probabilities and the associated gains and losses was given. Differently, old adults showed poor performance on the IGT relative to young adults, indicating difficulty in making advantageous decisions under ambiguous conditions. Indeed, in the IGT, participants are not aware of the rules for gains and losses and have to learn about the utility of their selections through experience. Results of our analyses point to the contribution of executive functions to all types of decisions. Our findings have also practical implications, suggesting that old people can make advantageous decisions when complete information about the decision situation is available. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
Performance indicators were built for the Instituto de Biofisica Carlos Chagas Filho, one of the most well-reputed Brazilian science centers. The Institute's performance presents a positive trend—articles number have doubled (1981–1995), and the articles impact grew from 4.20, in 1981, to 7.78, in 1990. This trend is probably being influenced by increasingly human resources involved in the Institute's scientific activities and by the continous growth of national and international collaboration. The follow up of indicators trends can be useful for the evaluation of long term policies directed to implement human resources programs and institutional collaborative work among scientific institutions.  相似文献   
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