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31.
Background
Dietary supplement use is increasing despite lack of evidence of benefits, or evidence of harm. Press releases issued by the supplements industry might contribute to this situation by using ‘spin’ (strategies to hype or denigrate findings) to distort the results of clinical studies. We assessed press releases issued in response to publication of clinical studies on dietary supplements.Methods and Findings
We analyzed 47 supplements industry press releases and 91 non-industry press releases and news stories, generated in response to 46 clinical studies of dietary supplements published between 1/1/2005 and 5/31/2013. The primary outcome was ‘spin’ content and direction. We also assessed disposition towards use of dietary supplements, reporting of study information, and dissemination of industry press releases. More supplements industry press releases (100%) contained ‘spin’ than non-industry media documents (55%, P<0.001). Hyping ‘spin’ scores were higher in industry than non-industry media documents for studies reporting benefit of supplements (median ‘spin’ score 3.3, 95% CI 1.0–5.5 vs 0.5, 0–1.0; P<0.001). Denigratory ‘spin’ scores were higher in industry than non-industry media documents for studies reporting no effect (6.0, 5.0–7.0 vs 0, 0–0; P<0.001) or harm (6.0, 5.5–7.5 vs 0, 0–0.5; P<0.001) from a supplement. Industry press releases advocated supplement use in response to >90% of studies that reported no benefit, or harm, of the supplement. Industry press releases less frequently reported study outcomes, sample size, and estimates of effect size than non-industry media documents (all P<0.001), particularly for studies that reported no benefit of supplements. Industry press releases were referenced by 148 news stories on the websites of 6 organizations that inform manufacturers, retailers and consumers of supplements.Conclusions
Dietary supplements industry press releases issued in response to clinical research findings are characterized by ‘spin’ that hypes results that are favourable to supplement use and denigrates results that are not. 相似文献32.
M. Navajas J. Gutierrez O. Bonato H. R. Bolland S. Mapangou-Divassa 《Experimental & applied acarology》1994,18(6):351-360
Intraspecific diversity in Cassava Green Mite Mononychellus progresivus Doreste was examined using individuals collected in Benin and the Congo and in Columbia and Brazil. Comparisons were based on mitochondrial and ribosomal DNA sequences and the results of several cross-breeding experiments. Sequence variation was examined in a total of 1139 base pairs (bp) constituting the ITS2 ribosomal DNA (805 bp) and a fragment of the Cytochrome Oxidase I (COI) gene (334 bp). Sequence divergence is low, ranging from 0% to 2.1% for COI and from 0% to 0.4% for ITS2. Inter-strain comparisons have shown that the two African populations appear to be identical. They were similar to the Colombian population while the Brazilian population was clearly different. The data support the hypothesis of a single introduction of the species in the two African populations. Crossing experiments have shown partial hybrid sterility, suggesting a genetic incompatibility consistent with differences detected by sequence data. The results show the usefulness of molecular markers as a tool for determining taxonomic status and dispersion paths in spider mites. 相似文献
33.
Vibrios associated with Litopenaeus vannamei larvae, postlarvae, broodstock, and hatchery probionts. 总被引:4,自引:0,他引:4
J Vandenberghe L Verdonck R Robles-Arozarena G Rivera A Bolland M Balladares B Gomez-Gil J Calderon P Sorgeloos J Swings 《Applied and environmental microbiology》1999,65(6):2592-2597
Several bacteriological surveys were performed from 1994 to 1996 at different Litopenaeus vannamei hatcheries (in Ecuador) and shrimp farms (in Mexico). Samples were taken from routine productions of healthy and diseased L. vannamei larvae, postlarvae, and their culture environment and from healthy and diseased juveniles and broodstock. In Ecuador, the dominant bacterial flora associated with shrimp larvae showing symptoms of zoea 2 syndrome, mysis mold syndrome, and bolitas syndrome has been determined. Strains were characterized by Biolog metabolic fingerprinting and identified by comparison to a database of 850 Vibrio type and reference strains. A selection of strains was further genotypically fine typed by AFLP. Vibrio alginolyticus is predominantly present in all larval stages and is associated with healthy nauplius and zoea stages. AFLP genetic fingerprinting shows high genetic heterogeneity among V. alginolyticus strains, and the results suggest that putative probiotic and pathogenic strains each have specific genotypes. V. alginolyticus was found to be associated with larvae with the zoea 2 syndrome and the mysis mold syndrome, while different Vibrio species (V. alginolyticus and V. harveyi) are associated with the bolitas syndrome. V. harveyi is associated with diseased postlarvae, juveniles, and broodstock. The identities of the strains identified as V. harveyi by the Biolog system could not be unambiguously confirmed by AFLP genomic fingerprinting. Vibrio strain STD3-988 and one unidentified strain (STD3-959) are suspected pathogens of only juvenile and adult stages. V. parahaemolyticus, Photobacterium damselae, and V. mimicus are associated with juvenile and adult stages. 相似文献
34.
Abstract: The two odontocete taxa Squalodon grateloupii and Patriocetus ehrlichii, both the type species of their respective genera, have been at the centre of a great deal of taxonomic confusion. Originally regarded to be conspecific, these two taxa have been the subject of a bewildering taxonomic debate lasting for more than a century, which recently led to the suggestion to abandon these widely used names and replace S. grateloupii with the similar, yet independently and later proposed name S. gratelupi as the type species of Squalodon. Here, we attempt to summarise the events leading to the current confused situation in the hope of resolving this issue once and for all and argue that the name Squalodon grateloupii, as originally proposed, should be reinstated. 相似文献
35.
36.
Matxalen Llosa Silvia Bolland Fernando de la Cruz 《Molecular & general genetics : MGG》1991,226(3):473-483
Summary We cloned and sequenced a 402 by DNA segment containing the origin of conjugal transfer (oriT) of the IncW plasmid R388. Progressive deletions from each end of the sequence were assayed for oriT activity. Stepwise reductions in mobilization frequencies, representing the loss of functional elements, correlated with deletion of structural motifs in the sequence. A sequence of 330 by of oriT was sufficient for efficient mobilization. The first 86 by of the sequence contains five tandemly repeated DNA sequences of 11 bp, followed by a 10 by perfect inverted repeat. Deletion of the first 95 by reduced the frequency of transfer by a hundred-fold. The sequence between by 183 and 218 was necessary and sufficient for low frequency mobilization and, thus, it was assumed to contain the nick site. This basis core was cloned as a 60 by segment (from by 176–236) that could be mobilized at low frequency. It includes two inverted repeats and a perfect integration host factor (IHF) consensus binding site. A third functionally important segment in oriT was located between by 260 and 330. The DNA sequence of the oriT of R388 could be aligned with that of the broad-host-range IncN plasmid R46. Moreover, the relative positions of the three inverted repeats are also conserved. Overall sequence similarity was 52%, but was significantly higher in particular regions, whch coincided with the functionally important segments mapped by deletion analysis. Conservation of these segments provided independent support for their essential role in oriT function. 相似文献
37.
The hha gene modulates haemolysin expression in Escherichia coli 总被引:5,自引:2,他引:3
J. M. Nieto M. Carmona S. Bolland Y. Jubete F. de la Cruz A. Juárez 《Molecular microbiology》1991,5(5):1285-1293
A mutation in the hha allele results in a large increase in the production of intracellular as well as extracellular haemolysin in Escherichia coli cells harbouring the haemolytic recombinant plasmid pANN202-312. This single gene mutation was located between 490 and 491.6kb on the physical map of the E. coli chromosome. From the DNA sequence of hha a small polypeptide of 8629 Da was predicted and was expressed in minicells. The deduced polypeptide sequence did not show significant similarities to other characterized proteins related to the regulation of gene expression in E. coli, although it was shown that the hha mutation increases cyloplasmic synthesis of haemolysin. 相似文献
38.
39.
High-resolution mapping of mouse Chromosome 8 identifies an evolutionary chromosomal breakpoint 总被引:3,自引:0,他引:3
Prabhjit K. Grewal Daniel J. Bolland Laura Carim Todd Jane E. Hewitt 《Mammalian genome》1998,9(8):603-607
The central region of mouse Chromosome (Chr) 8, containing the myodystrophy (myd) locus, is syntenic with human Chr 4q28-qter. The human neuromuscular disorder facioscapulohumeral muscular dystrophy (FSHD)
maps to Chr 4q35, and myd has been proposed as a mouse homolog of FSHD. We have employed a comparative mapping approach to investigate this relationship
further by extending the mouse genetic map of this region. We have ordered 12 genes in a single cross, 8 of which have human
homologs on 4q28-qter. The results confirm a general relationship between the most distal genes on human 4q and the most proximal
genes in the mouse 8 syntenic region. Despite chromosomal rearrangements of syntenic groups in this region, conservation of
gene order is maintained between the group of genes in the human telomeric region of 4q35 and MMU8. Furthermore, this conserved
telomeric HSA4q35 syntenic group maps proximal to the myd mutation and is flanked by genes with homologs on HSA8p22. At the proximal boundary of the MMU8 linkage group we have identified
a single 300-kb YAC containing the genes Frgl and Pcml, which have human homologs on 4q35 and 8p22, respectively. Thus, this YAC spans an evolutionary chromosomal breakpoint. As
well as providing clues about chromosomal evolution, this map of the FSHD syntenic mouse region should prove invaluable in
the isolation of candidate genes for this disease.
Received: 20 January 1998 / Accepted: 10 April 1998 相似文献
40.