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71.
Ahnström J Axler O Jauhiainen M Salomaa V Havulinna AS Ehnholm C Frikke-Schmidt R Tybjaerg-Hansen A Dahlbäck B 《Journal of lipid research》2008,49(9):1912-1917
Apolipoprotein M (apoM), a 25 kDa plasma protein belonging to the lipocalin protein family, is predominantly associated with HDL. Studies in mice have suggested apoM to be important for the formation of pre-beta-HDL and to increase cholesterol efflux from macrophage foam cells. Overexpression of human apoM in LDL receptor-deficient mice reduced the atherogenic effect of a cholesterol-rich diet. The aim of the present study was to investigate whether the apoM levels in man predict the risk for coronary heart disease (CHD). ApoM was measured in samples from two separate case-control studies. FINRISK '92 consisted of 255 individuals, of whom 80 developed CHD during follow-up and 175 were controls. The Copenhagen City Heart Study included 1,865 individuals, of whom 921 developed CHD during follow-up and 944 were controls. Correlation studies of apoM concentration with several analytes showed a marked positive correlation with HDL and total cholesterol as well as with apoA-I and apoB. There was no significant difference in mean apoM level between CHD and control subjects in either study. In conditional logistic regression analyses, apoM was not a predictor of CHD events, [odds ratio (95% CI) 0.97 (0.74-1.27) and 0.92 (0.84-1.02), respectively]. In conclusion, no association between apoM and CHD could be found in this study. 相似文献
72.
Sara H?gg Josefin Skogsberg Jesper Lundstr?m Peri Noori Roland Nilsson Hua Zhong Shohreh Maleki Ming-Mei Shang Bj?rn Brinne Maria Bradshaw Vladimir B. Bajic Ann Samneg?rd Angela Silveira Lee M. Kaplan Bruna Gigante Karin Leander Ulf de Faire Stefan Rosfors Ulf Lockowandt Jan Liska Peter Konrad Rabbe Takolander Anders Franco-Cereceda Eric E. Schadt Torbj?rn Ivert Anders Hamsten Jesper Tegnér Johan Bj?rkegren 《PLoS genetics》2009,5(12)
73.
2'-Deoxyadenosine (dA) and 2'-deoxyguanosine (dG) were reacted with mutagenic epoxide glycidamide (GA, Scheme 1). The reactions yielded three GA-dA adducts (N1-GA-dA, N6-GA-dA and N1-GA-dI) and two GA-dG adducts (N1-GA-dG I and N1-GA-dG II) (Scheme 2). The structures of the adducts were characterized by spectroscopic and spectrometric methods (1H-, 13C, and 2D NMR, MS, UV). The mechanism of the amide hydrolysis taking place during formation of the adducts N1-GA-dA and N1-GA-dG I was studied. We propose a mechanism where a transamidation is the key step in the hydrolysis of the amide function of GA. 相似文献
74.
Lisa Hefele Antony P. Black Trinh Van Tan Nguyen Tri Minh Nguyen Duc Hoang Siriphone Virachith Claude P. Muller Judith M. Hübschen Paula Russell Josefin Bartholdson Scott Chau Nguyen Ngoc Minh Tran Vu Thieu Nga Stephen Baker 《PLoS neglected tropical diseases》2021,15(12)
The epidemiology of typhoid fever in Lao People`s Democratic Republic is poorly defined. Estimating the burden of typhoid fever in endemic countries is complex due to the cost and limitations of population-based surveillance; serological approaches may be a more cost-effective alternative. ELISAs were performed on 937 serum samples (317 children and 620 adults) from across Lao PDR to measure IgG antibody titers against Vi polysaccharide and the experimental protein antigens, CdtB and HlyE. We measured the significance of the differences between antibody titers in adults and children and fitted models to assess the relationship between age and antibody titers. The median IgG titres of both anti-HylE and CdtB were significantly higher in children compared to adults (anti-HylE; 351.7 ELISA Units (EU) vs 198.1 EU, respectively; p<0.0001 and anti-CdtB; 52.6 vs 12.9 EU; p<0.0001). Conversely, the median anti-Vi IgG titer was significantly higher in adults than children (11.3 vs 3.0 U/ml; p<0.0001). A non-linear trend line fitted to the anti-CdtB and anti-HlyE IgG data identified a peak in antibody concentration in children <5 years of age. We identified elevated titers of anti-HlyE and anti-CdtB IgG in the serum of children residing in Lao PDR in comparison to adults. These antigens are associated with seroconversion after typhoid fever and may be a superior measure of disease burden than anti-Vi IgG. This approach is scalable and may be developed to assess the burden of typhoid fever in countries where the disease may be endemic, and evidence is required for the introduction of typhoid vaccines. 相似文献
75.
Background and Aims
Heritable genetic variation is crucial for selection to operate, yet there is a paucity of studies quantifying such variation in interactive male/female sexual traits, especially those of plants. Previous work on the annual plant Collinsia heterophylla, a mixed-mating species, suggests that delayed stigma receptivity is involved in a sexual conflict: pollen from certain donors fertilize ovules earlier than others at the expense of reduced maternal seed set and lower levels of pollen competition.Methods
Parent–offspring regressions and sib analyses were performed to test for heritable genetic variation and co-variation in male and female interactive traits related to the sexual conflict.Key Results
Some heritable variation and evolvability were found for the female trait (delayed stigma receptivity in presence of pollen), but no evidence was found for genetic variation in the male trait (ability to fertilize ovules early). The results further indicated a marginally significant correlation between a male''s ability to fertilize early and early stigma receptivity in offspring. However, despite potential indirect selection of these traits, antagonistic co-evolution may not occur given the lack of heritability of the male trait.Conclusions
To our knowledge, this is the first study of a plant or any hermaphrodite that examines patterns of genetic correlation between two interactive sexual traits, and also the first to assess heritabilities of plant traits putatively involved in a sexual conflict. It is concluded that the ability to delay fertilization in presence of pollen can respond to selection, while the pollen trait has lower evolutionary potential. 相似文献76.
77.
Mitomycin C (MC) -induced chromatid aberrations among the chromosomes of Microtus agrestis are preferentially localized in the constitutive heterochromatic regions, i.e., major part of the sex chromosomes and the centromeric regions of the autosomes. In the sex chromosomes, intrachanges predominate, while interchanges between the two X chromosomes are very rare. This pattern of distribution of different types of aberrations is interpreted as due to the individual chromocentres that are formed by the two X chromosomes in the interphase. 相似文献
78.
Axelsson J Sverrisson K Rippe A Fissell W Rippe B 《American journal of physiology. Renal physiology》2011,301(4):F708-F712
The glomerular filtration barrier (GFB) is commonly conceived as a negatively charged sieve to proteins. Recent studies, however, indicate that glomerular charge effects are small for anionic, carboxymethylated (CM) dextran vs. neutral dextran. Furthermore, two studies assessing the glomerular sieving coefficients (θ) for negative CM-Ficoll vs. native Ficoll have demonstrated an increased glomerular permeability for CM-Ficoll (Asgeirsson D, Venturoli D, Rippe B, Rippe C. Am J Physiol Renal Physiol 291: F1083-F1089, 2006; Guimar?es M, Nikolovski J, Pratt L, Greive K, Comper W. Am Physiol Renal Physiol 285: F1118-F1124, 2003.). The CM-Ficoll used, however, showed a larger Stokes-Einstein radius (a(e)) than neutral Ficoll, and it was proposed that the introduction of negative charges in the Ficoll molecule had made it more flexible and permeable. Recently, a negative FITC-labeled CM-Ficoll (CMI-Ficoll) was produced with a conformation identical to that of neutral FITC-Ficoll. Using these probes, we determined their θ:s in anesthetized Wistar rats (259 ± 2.5 g). After blood access had been achieved, the left ureter was cannulated for urine sampling. Either polysaccharide was infused (iv) together with a filtration marker, and urine and plasma were collected. Assessment of θ FITC-Ficoll was achieved by high-performance size-exclusion chromatography (HPSEC). CMI-Ficoll and native Ficoll had identical elugrams on the HPSEC. Diffusion of anionic Ficoll was significantly reduced compared with that of neutral Ficoll across the GFB for molecules of a(e) ~20-35 ?, while there were no charge effects for Ficoll of a(e) = 35-80 ?. The data are consistent with a charge effect present in "small pores," but not in "large pores," of the GFB and mimicked those obtained for anionic membranes in vitro for the same probes. 相似文献
79.
Nature represents a vast source of chemical diversity, which is supposed to cover broader areas of chemical space than synthetically obtained substances typical of medicinal chemistry. With regard to drug discovery from nature, the terrestrial environment has been the most and longest studied source, while the investigation of compounds produced by marine organisms is still in its infancy. With the objective of demonstrating the enormous chemical diversity of nature, in particular that of the marine environment, we used the chemical space navigation tool ChemGPS-NP to compare sets of marine, terrestrial and synthetic compounds with respect to physico-chemical properties and their occupation of the biologically relevant chemical space. Despite considerable overlap, the three datasets clearly differ from each other by occupying and extending into different, specific, regions in chemical space. Synthetic compounds are e.g. comparably small, with some of them being highly flexible, while marine and terrestrial products are larger and characterised by higher and lower molecular flexibility, respectively, with increasing size. Moreover, the three datasets differ to some degree in polarity, aromaticity and heteroatom content. Taken together, ChemGPS-NP has been proven to be a useful tool for navigating large volumes of biologically relevant chemical space. In this study we demonstrated the chemical uniqueness and differences of large sets of natural products, with particular emphasis on marine substances. The hence de-veiled differences further underline the relevance of natural products, of both marine and terrester origin, for future drug discovery. 相似文献
80.
Ryan T. Demmer Ludovic Trinquart Aleksandra Zuk Benjamin C. Fu Josefin Blomkvist Bryan S. Michalowicz Philippe Ravaud Mo?se Desvarieux 《PloS one》2013,8(10)