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21.
This work describes the draft genome sequence of Lactococcus garvieae DCC43. The 2.2-Mb draft genome contains 2,227 predicted protein-coding genes, among which is a region encoding the bacteriocin garvicin ML. No antibiotic resistance genes or capsule-related virulence genes were identified. Two plasmid replication regions indicate that this strain likely contains plasmids. Comparative genomics suggests that this strain displays a high degree of sequence variation from the previously sequenced L. garvieae strains.  相似文献   
22.

Background

Several studies have shown an association between vitamin D deficiency and cardiovascular risk. Vitamin D status is assessed by determination of 25-hydroxyvitamin D [25(OH)D] in serum.

Methods

We assessed the prognostic utility of 25(OH)D in 982 chest-pain patients with suspected acute coronary syndrome (ACS) from Salta, Northern Argentina. 2-year follow-up data including all-cause mortality, cardiac death and sudden cardiac death were analyzed in quartiles of 25(OH)D, applying univariate and multivariate analysis.

Results

There were statistically significant changes in seasonal 25(OH)D levels. At follow-up, 119 patients had died. The mean 25(OH)D levels were significantly lower among patients dying than in long-term survivors, both in the total population and in patients with a troponin T (TnT) release (n = 388). When comparing 25(OH)D in the highest quartile to the lowest quartile in a multivariable Cox regression model for all-cause mortality, the hazard ratio (HR) for cardiac death and sudden cardiac death in the total population was 0.37 (95% CI, 0.19–0.73), p = 0.004, 0.23 (95% CI, 0.08–0.67), p = 0.007, and 0.32 (95% CI, 0.11–0.94), p = 0.038, respectively. In patients with TnT release, the respective HR was 0.24 (95% CI, 0.10–0.54), p = 0.001, 0.18 (95% CI, 0.05–0.60), p = 0.006 and 0.25 (95% CI, 0.07–0.89), p = 0.033. 25(OH)D had no prognostic value in patients with no TnT release.

Conclusion

Vitamin D was shown to be a useful biomarker for prediction of mortality when obtained at admission in chest pain patients with suspected ACS.

Trial registration

ClinicalTrials.gov NCT01377402  相似文献   
23.
This work describes the purification and characterization of propionicin F, the first bacteriocin isolated from Propionibacterium freudenreichii. The bacteriocin has a bactericidal activity and is only active against strains of P. freudenreichii. Propionicin F appears to be formed through a processing pathway new to bacteriocins. The mass of the purified bacteriocin was determined by mass spectrometry, and the N-terminal amino acid sequence was determined by Edman degradation. Sequencing of pcfA, the bacteriocin structural gene, revealed that propionicin F corresponds to a 43-amino-acid peptide in the central part of a 255-amino-acid open reading frame, suggesting that mature propionicin F is excised from the probacteriocin by N- and C-terminal proteolytic modifications. DNA sequencing and Northern blot hybridizations revealed that pcfA is cotranscribed with genes encoding a putative proline peptidase and a protein from the radical S-adenosylmethionine family. A gene encoding an ABC transporter was also identified in close proximity to the bacteriocin structural gene. The potential role of these genes in propionicin F maturation and secretion is discussed.  相似文献   
24.
The Common Toad Bufo bufo is a wide‐ranging species, with a distribution encompassing much of Europe and Asia. Few molecular studies have been undertaken on this species, and only one polymorphic microsatellite locus has been identified. Therefore, little is known about the genetic variability within and between B. bufo populations. The value of such information is essential for monitoring the species and its environment. This paper reports the characterization of 15 B. bufo microsatellite loci using individuals from a Spanish and UK sample.  相似文献   
25.
trans-Resveratrol (trans-3,5,4'-trihydroxystilbene) is a nonflavonoid polyphenol reported to exert different biological activities, among them inhibition of the lipid peroxidation, scavenging of the free radicals, inhibition of the platelet aggregation, and anticancer activity as the most important. In order to enlighten the radical-scavenging mechanism of trans-resveratrol, stationary gamma-radiolytic experiments in liposomes and pulse radiolytic experiments in aqueous solutions were performed. Applying the stationary gamma-radiolysis together with the subsequent product analysis, reactions of lipid peroxyl radicals, LOO*, with trans-resveratrol and other natural antioxidants were investigated. It was found that trans-resveratrol was a better radical scavenger than vitamins E and C but similar to the flavonoids epicatechin and quercetin. The comparison of the radical-scavenging effects of trans-resveratrol and its analogues trans-4-hydroxystilbene and trans-3,5-dihydroxystilbene revealed that trans-resveratrol and trans-4-hydroxystilbene showed almost the same effect and were more efficient than trans-3,5-dihydroxystilbene. These findings indicate greater radical-scavenging activity of trans-resveratrols para-hydroxyl group than its meta-hydroxyl groups. Using the pulse radiolysis, reactions of trans-resveratrol and its analogues with trichloromethylperoxyl radicals, CCl(3)OO*, were studied. Spectral and kinetic properties of the observed transients showed great similarity between trans-resveratrol and trans-4-hydroxystilbene which seems to confirm that para-hydroxyl group of trans-resveratrol scavenges free radicals more effectively than its meta-hydroxyl groups.  相似文献   
26.
A rapid PCR-based method for genetically mapping ESTs   总被引:12,自引:0,他引:12  
A simple, semi-automatable procedure was developed for converting expressed sequence tags (ESTs) into mappable genetic markers. The polymerase chain reaction is used to amplify regions immediately 5′ or 3′ to the coding regions of genes in order to maximise sequence variability between alleles. Fragment length and nucleotide substitution polymorphisms among amplified alleles can be detected using either ethidium bromide staining or automated laser-based fluorescence. A 6% non-denaturing acrylamide gel, analysed with an ABI 377 DNA sequencer, proved capable of resolving homoduplexes and heteroduplexes formed between amplified alleles containing nucleotide substitutions as well as resolving allelic length differences. With this approach 75% of 60 ESTs from a range of Pinus species could be genetically mapped in each of three pedigrees from P. radiata and P. taeda. Furthermore, three or four alleles were detected in each pedigree for 42% of the EST markers. Received: 4 January 2000 / Accepted: 26 May 2000  相似文献   
27.
28.
BAG-1 family of cochaperones in the modulation of nuclear receptor action   总被引:5,自引:0,他引:5  
BAG-1 is a family of cochaperones consisting of at least four polypeptides BAG-1L, BAG-1M/RAP46, BAG-1 and p29. These proteins are translated from the same mRNA at alternative translation initiation sites. They possess conserved carboxy-terminal sequences which enable them to bind and inhibit the action of the molecular chaperone Hsp70/Hsc70. BAG-1 was the first member in the family of the BAG-1 proteins to be isolated. It was identified as an anti-apoptotic protein because of its ability to bind and augment the activity of the anti-death protein, Bcl-2. Since then other BAG-1 proteins have been identified and shown to interact with several cellular factors including nuclear receptors. Recent findings show that the effect of the BAG-1 proteins on nuclear receptors ranges from inhibition to enhancement of the transactivation functions of the receptors. Available data on the negative regulation of glucocorticoid receptor (GR) action by the BAG-1 proteins identify two modes of action: inhibition of the hormone binding activity of the GR and a more direct nuclear action at the level of regulation of the transactivation function of the receptor. In the latter case, the BAG-1 proteins repress DNA binding by the GR in a process that requires prior binding of Hsp70/Hsc70 to the receptor. Positive regulatory action of the BAG-1 proteins on nuclear receptors has also been reported which may involve yet other mechanisms. This review puts together recent findings on the action the BAG-1 proteins and presents them as a novel group of regulators of action of nuclear receptor.  相似文献   
29.
30.
The Daphnia longispina complex contains some of the most common water flea species in the northern hemisphere, and has been a model organism for many ecological and evolutionary studies. Nevertheless, the systematics and nomenclature of this group, in particular its Palaearctic members, have been in flux for the past 150 years; this hinders the correct interpretation of scientific results and promotes the erroneous use of species names. We revise the systematics of this species complex based on mitochondrial sequence variation (12S rDNA and COI) of representative populations across Europe, with a special focus on samples from type localities of the respective taxa. Combining genetic evidence and morphological assignments of analysed individuals, we propose a comprehensive revision of the European members of the D. longispina complex. We show that D. hyalina and D. rosea morphotypes have evolved several times independently, and we find no evidence to maintain these morphotypes as distinct biological species. Alpine individuals described as D. zschokkei are conspecific with the above-mentioned lineage. We suggest that this morphologically and ecologically plastic but genetically uniform hyalina–rosea–zschokkei clade should be identified as D. longispina (O. F. Müller, 1776). The valid name of Fennoscandian individuals labelled D. longispina sensu stricto in the recent literature is D. lacustris G. O. Sars, 1862. Additionally, we discovered another divergent lineage of this group, likely an undescribed species, in southern Norway. Our results present a solution for several prevailing taxonomic problems in the genus Daphnia , and have broad implications for interpretation of biogeographical patterns, and ecological and evolutionary studies.  相似文献   
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