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81.
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Background

Recent experimental evidence suggests that socioeconomic characteristics of neighbourhoods influence cardiovascular health, but observational studies which examine deprivation across a wide range of cardiovascular diseases (CVDs) are lacking.

Methods

Record-linkage cohort study of 1.93 million people to examine the association between small-area socioeconomic deprivation and 12 CVDs. Health records covered primary care, hospital admissions, a myocardial infarction registry and cause-specific mortality in England (CALIBER). Patients were aged ≥30 years and were initially free of CVD. Cox proportional hazard models stratified by general practice were used.

Findings

During a median follow-up of 5.5 years 114,859 people had one of 12 initial CVD presentations. In women the hazards of all CVDs except abdominal aortic aneurysm increased linearly with higher small-area socioeconomic deprivation (adjusted HR for most vs. least deprived ranged from 1.05, 95%CI 0.83–1.32 for abdominal aortic aneurysm to 1.55, 95%CI 1.42–1.70 for heart failure; I2 = 81.9%, τ2 = 0.01). In men heterogeneity was higher (HR ranged from 0.89, 95%CI 0.75–1.06 for cardiac arrest to 1.85, 95%CI 1.67–2.04 for peripheral arterial disease; I2 = 96.0%, τ2 = 0.06) and no association was observed with stable angina, sudden cardiac death, subarachnoid haemorrhage, transient ischaemic attack and abdominal aortic aneurysm. Lifetime risk difference between least and most deprived quintiles was most marked for peripheral arterial disease in women (4.3% least deprived, 5.8% most deprived) and men (4.6% least deprived, 7.8% in most deprived); but it was small or negligible for sudden cardiac death, transient ischaemic attack, abdominal aortic aneurysm and ischaemic and intracerebral haemorrhage, in both women and men.

Conclusions

Associations of small-area socioeconomic deprivation with 12 types of CVDs were heterogeneous, and in men absent for several diseases. Findings suggest that policies to reduce deprivation may impact more strongly on heart failure and peripheral arterial disease, and might be more effective in women.  相似文献   
84.
Abstract In order to characterize the metabolites produced in vivo by biphenyl-2,3-dioxygenase and biphenyl-2,3-dihydrodiol-2,3-dehydrogenase, the first two enzymes of the (polychloro)biphenyl catabolic pathway encoded by the bph locus of Pseudomonas sp. LB400, recombinant E. coli strains expressing the respective genes were constructed. Biphenyl-2,3-dioxygenase attack on 2,2'- or 2,4'-dichlorobiphenyl was shown to give rise to virtually quantitative ortho -dechlorination of these congeners by hydroxylation at the chlorinated carbon 2 and its unsubstituted neighbour. Elimination of hydrochloric acid directly leads to 2,3-dihydroxy-chlorobiphenyls and obviates the need for biphenyl-2,3-dihydrodiol-2,3-dehydrogenase for the catabolism of such congeners.  相似文献   
85.
Universal barrier to lateral spread of specific genes among microorganisms   总被引:6,自引:0,他引:6  
A genetic circuit to suppress the lateral spread of cloned genes from recombinant to indigenous microorganisms in the environment has been developed. It is based on the endonucleolytic activity of the bacterial toxin colicin E3, which has a distinct target at the 3 end of the 16S ribosomal RNA; this sequence is conserved in virtually all prokaryotic and many eukaryotic genera. Cleavage at this sequence separates the mRNA binding sites from the remainder of the 16S rRNA, thereby inhibiting protein synthesis. While host bacteria carrying the genes for both colicin production and colicin immunity are perfectly viable, lateral transfer of the E3 gene to non-immune reciptents results in killing of such recipients. This genetic circuit decreases operational transfer frequencies of cloned genes linked to the E3 gene among a variety of bacterial genera by four to five orders of magnitude, in combination with transposon cloning vectors, the circuit is predicted to reduce the rate of lateral spread of specific genes to ecologically insignificant levels. This system therefore represents a useful tool both to explore the evolutionary and ecological consequences of experimentally reducing lateral gene spread among microorganisms, and to increase the ecological predictability of novel recombinant microorganisms.  相似文献   
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A simple procedure for cloning and stable insertion of foreign genes into the chromosomes of gram-negative eubacteria was developed by combining in two sets of plasmids (i) the transposition features of Tn10 and Tn5; (ii) the resistances to the herbicide bialaphos, to mercuric salts and organomercurial compounds, and to arsenite, and (iii) the suicide delivery properties of the R6K-based plasmid pGP704. The resulting constructions contained unique NotI or SfiI sites internal to either the Tn10 or the Tn5 inverted repeats. These sites were readily used for cloning DNA fragments with the help of two additional specialized cloning plasmids, pUC18Not and pUC18Sfi. The newly derived constructions could be maintained only in donor host strains that produce the R6K-specified pi protein, which is an essential replication protein for R6K and plasmids derived therefrom. Donor plasmids containing hybrid transposons were transformed into a specialized lambda pir lysogenic Escherichia coli strain with a chromosomally integrated RP4 that provided broad-host-range conjugal transfer functions. Delivery of the donor plasmids into selected host bacteria was accomplished through mating with the target strain. Transposition of the hybrid transposon from the delivered suicide plasmid to a replicon in the target cell was mediated by the cognate transposase encoded on the plasmid at a site external to the transposon. Since the transposase function was not maintained in target cells, such cells were not immune to further transposition rounds. Multiple insertions in the same strain are therefore only limited by the availability of distinct selection markers. The utility of the system was demonstrated with a kanamycin resistance gene as a model foreign insert into Pseudomonas putida and a melanin gene from Streptomyces antibioticus into Klebsiella pneumoniae. Because of the modular nature of the functional parts of the cloning vectors, they can be easily modified and further selection markers can be incorporated. The cloning system described here will be particularly useful for the construction of hybrid bacteria that stably maintain inserted genes, perhaps in competitive situations (e.g., in open systems and natural environments), and that do not carry antibiotic resistance markers characteristic of most available cloning vectors (as is currently required of live bacterial vaccines).  相似文献   
88.
Summary The interaction between flax rust,Melampsora lini, and its host, flax,Linum usitatissimum, has been extensively studied, and certain genetic features make the system an appropriate choice to utilize in isolating genes conferring avirulence in rust. A mutant that was selected for virulence on Lx plants was isolated, after treatment with gamma rays, from a strain that is genotypicallyA-L5,A-L6,A-L7,A-Lx/A-L5,A-L6,a-L7,a-Lx. These four specificities are tightly linked. Breeding tests showed that this mutant was genotypicallyA-L5,A-L6,a-L7,a-Lx/a-L5,a-L6,a-L7,a-Lx and, when made homozygous for the mutant chromosome, was virulent onL5,L6,L7, andLx. This result excludes somatic recombination as a source of the mutation and indicates deletion as a likely cause. A 250 bp genomic sequence from a strain of rust homozygous for these four linked avirulence genes (A-L5,A-L6,A-L7,A-Lx) was isolated, using a method that allows the differential cloning of the specific DNA sequences located within a deletion in the mutant genome. This clone hybridized to two EcoRI bands in genomic DNA from the strain homozygous for the four linked avirulence genes and from the strain homozygousA-L5 andA-L6 and heterozygousA-L7 andA-Lx, but showed no homology to DNA from the strain carrying the putative chromosomal deletion. The correlation between the genetically characterized deletion mutation and the isolation of a sequence from within a region of chromosome missing from this strain of rust suggests that this 250 bp tract may be part of, or closely linked to, the defined set of avirulence genes.  相似文献   
89.
The conversion of substituted benzoates into 1,2-cis-dihydroxycyclohexa-3,5-diene carboxylic acids (cis-diols) was effected by using Escherichia coli and Pseudomonas recombinants carrying the xylXYZ genes originating from the Pseudomonas putida mt-2 TOL plasmid, thus producing toluate-1,2-dioxygenase. Pseudomonas oleovorans GPo12 recombinants readily produced meta- and para-substituted cis-diols, but were limited in their oxidation of ortho-substituted substrates.  相似文献   
90.
Plagiotropic angle of seedling-derived Douglas-fir plantlets varied with position of adventitious bud origin on the explanted cotyledon rosette, being least at its center (18°) and greatest (45°) along the basal third of the cotyledon. When the tops of plagiotropic plantlets (55°) were grafted to seedling rootstock, they assumed a near-vertical orientation (10°), with pectinate changed to radial leaf arrangement, within 5 months. Conversely, seedling tops grafted to plagiotropic plantlet rootstock grew plagiotropically (56°). These, and other observations lead to a hypothesis that plagiotropism in cotyledon-derived plantlets results in part from an incomplete vascular connection of the root system to the shoot.In contrast, the greater plagiotropic angle in plantlets from a 12 year-old tree, decreased by only half (from 72° to 34°) after grafting to seedling rootstock. First-season height increment of these plantlets was only 60 percent of seedling or juvenile plantlet height increment, and was unaffected by rootstock type. The adult-origin plantlets exhibited mature shoot morphology, and unchanged plagiotropism after 2 years growth in large pots. Thus it appears that the culture-induced juvenile appearance and behaviour noted for this material when maintained in vitro, is dependent on the continued presence of the culture conditions.  相似文献   
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