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This prospective study of 1277 participants investigated patient risk self-assessment, motivation for changes in main determinants of the metabolic syndrome and the impact of community nursing intervention on cardiovascular risk reduction. Observed values of metabolic syndrome determinants indicated an elevated cardiovascular risk. Participants showed greatest motivation for positive changes regarding blood pressure, (3.70 +/- 1.26) then hyperglycemia (3.55 +/- 1.28), hyperlipidemia (3.46 +/- 1.30), overweight and obesity (3.43 +/- 1.28), and physical activity habits (3.29 +/- 1.31). Changes in physical activity and nutritional habits were not related to self-reported motivation regardless of the age and sex (p > 0.05). The most pronounced median improvements were observed in cholesterol (men 4.43%, women 4.89%) and triglycerides (men 3.41%, women 1.49%), with only slight changes in BMI (men 1.08%, women 1.18%) and no change in waist-to-hip ratio and glucose. This study revealed that, although aware and motivated, patients often do not succeed in changing habits. Concomitant changes of the environment and multisectoral prevention approach is necessary.  相似文献   
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Recently we demonstrated the control of a mucosal challenge with a pathogenic chimera of simian and human immunodeficiency virus (SHIV-89.6P) by priming with a Gag-Pol-Env-expressing DNA and boosting with a Gag-Pol-Env-expressing recombinant modified vaccinia virus Ankara (DNA/MVA) vaccine. Here we evaluate the ability of the MVA component of this vaccine to serve as both a prime and a boost for an AIDS vaccine. The same immunization schedule, MVA dose, and challenge conditions were used as in the prior DNA/MVA vaccine trial. Compared to the DNA/MVA vaccine, the MVA-only vaccine raised less than 1/10 the number of vaccine-specific T cells but 10-fold-higher titers of binding antibody for Env. Postchallenge, the animals vaccinated with MVA alone increased their CD8 cell numbers to levels that were similar to those seen in DNA/MVA-vaccinated animals. However, they underwent a slower emergence and contraction of antiviral CD8 T cells and were slower to generate neutralizing antibodies than the DNA/MVA-vaccinated animals. Despite this, by 5 weeks postchallenge, the MVA-only-vaccinated animals had achieved as good control of the viral infection as the DNA/MVA group, a situation that has held up to the present time in the trial (48 weeks postchallenge). Thus, MVA vaccines, as well as DNA/MVA vaccines, merit further evaluation for their ability to control the current AIDS pandemic.  相似文献   
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Seryl-tRNA synthetase (SerRS) is a class II aminoacyl-tRNA synthetase that catalyzes serine activation and its transfer to cognate tRNA(Ser). Previous biochemical and structural studies have revealed that bacterial- and methanogenic-type SerRSs employ different strategies of substrate recognition. In addition to other idiosyncratic features, such as the active site zinc ion and the unique fold of the N-terminal tRNA-binding domain, methanogenic-type SerRS is, in comparison with bacterial homologues, characterized by a notable shortening of the motif 2 loop. Mutational analysis of Methanosarcina barkeri SerRS (mMbSerRS) was undertaken to identify the active site residues that ensure the specificity of amino acid and tRNA 3'-end recognition. Residues predicted to contribute to the amino acid specificity were selected for mutation according to the crystal structure of mMbSerRS complexed with its cognate aminoacyl-adenylate, whereas those involved in binding of the tRNA 3'-end were identified and mutagenized on the basis of modeling the mMbSerRS:tRNA complex. Although mMbSerRSs variants with an altered serine-binding pocket (W396A, N435A, S437A) were more sensitive to inhibition by threonine and cysteine, none of the mutants was able to activate noncognate amino acids to greater extent than the wild-type enzyme. In vitro kinetics results also suggest that conformational changes in the motif 2 loop are required for efficient serylation.  相似文献   
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The methanogenic archaea Methanococcus jannaschii and M. maripaludis contain an atypical seryl-tRNA synthetase (SerRS), which recognizes eukaryotic and bacterial tRNAsSer, in addition to the homologous tRNASer and tRNASec species. The relative flexibility in tRNA recognition displayed by methanogenic SerRSs, shown by aminoacylation and gel mobility shift assays, indicates the conservation of some serine determinants in all three domains. The complex of M. maripaludis SerRS with the homologues tRNASer was isolated by gel filtration chromatography. Complex formation strongly depends on the conformation of tRNA. Therefore, the renaturation conditions for in vitro transcribed tRNASer(GCU) isoacceptor were studied carefully. This tRNA, unlike many other tRNAs, is prone to dimerization, possibly due to several stretches of complementary oligonucleotides within its sequence. Dimerization is facilitated by increased tRNA concentration and can be diminished by fast renaturation in the presence of 5 mm magnesium chloride.  相似文献   
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Placental selenium, lead and cadmium concentrations were determined in a group of pregnancies with birth weight appropriate for gestational age and in a group of intrauterine growth restriction cases. Following adjustment for a number of confounding variables, selenium was found to be a significant predictor of newborn weight only in the group of pregnancies with birth weights appropriate for gestational age. Placental lead and cadmium levels were not associated with birth weight in either group.  相似文献   
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Gestational diabetes mellitus (GDM) is associated with excessive oxidative stress which may affect placental vascular function. Cholesterol homeostasis is crucial for maintaining fetoplacental endothelial function. We aimed to investigate whether and how GDM affects cholesterol metabolism in human fetoplacental endothelial cells (HPEC). HPEC were isolated from fetal term placental arterial vessels of GDM or control subjects. Cellular reactive oxygen species (ROS) were detected by H2DCFDA fluorescent dye. Oxysterols were quantified by gas chromatography–mass spectrometry analysis. Genes and proteins involved in cholesterol homeostasis were detected by real-time PCR and immunoblotting, respectively. Cholesterol efflux was determined from [3H]-cholesterol labeled HPEC and [14C]-acetate was used as cholesterol precursor to measure cholesterol biosynthesis and esterification. We detected enhanced formation of ROS and of specific, ROS-derived oxysterols in HPEC isolated from GDM versus control pregnancies. ROS-generated oxysterols were simultaneously elevated in cord blood of GDM neonates. Liver-X receptor activation in control HPEC by synthetic agonist TO901319, 7-ketocholesterol, or 7β-hydroxycholesterol upregulated ATP-binding cassette transporters (ABC)A1 and ABCG1 expression, accompanied by increased cellular cholesterol efflux. Upregulation of ABCA1 and ABCG1 and increased cholesterol release to apoA-I and HDL3 (78?±?17%, 40?±?9%, respectively) were also observed in GDM versus control HPEC. The LXR antagonist GGPP reversed ABCA1 and ABCG1 upregulation and reduced the increased cholesterol efflux in GDM HPEC. Similar total cellular cholesterol levels were detected in control and GDM HPEC, while GDM enhanced cholesterol biosynthesis along with upregulated 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and sterol O-acyltransferase 1 (SOAT1) mRNA and protein levels. Our results suggest that in GDM cellular cholesterol homeostasis in the fetoplacental endothelium is modulated via LXR activation and helps to maintain its proper functionality.  相似文献   
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Excessive amounts of metal ions in soil are toxic for most plant species, yet metal can also facilitate plant survival by elemental defense against herbivores and pathogens. Zinc and cadmium hyperaccumulation in Arabidopsis halleri is known to be effective for the defense against natural enemies. The allotetraploid species A. kamchatica, derived from A. halleri and a non-hyperaccumulator A. lyrata, has a lower hyperaccumulation level of zinc than A. halleri, but its significance for elemental defense remains unknown. In this study, we evaluated the accumulation levels of zinc and cadmium in the allotetraploid compared with its diploid progenitors, and evaluated the contribution of metal treatments to anti-herbivore resistance under field conditions. The accumulation level of zinc in A. kamchatica was intermediate between the progenitors, but that of cadmium was lower than in both diploid progenitors. The elemental defense of A. kamchatica and A. halleri was supported by a field experiment comparing the herbivory level between a control group and metal-supplemented plants. Moreover, the effect of elemental defense was lower in A. kamchatica than in the hyperaccumulator progenitor A. halleri, which is consistent with the metal accumulation level. This result reveals that the allotetraploid plant inherited its hyperaccumulating ability from one progenitor as an advantageous trait but at an intermediate level.  相似文献   
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