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991.
Anna Taylor 《BMJ (Clinical research ed.)》1998,316(7138):1117-1122
Objective: To estimate the prevalence of violations of the international code of marketing of substitutes for breast milk in one city in each of Bangladesh, Poland, South Africa, and Thailand. Design: Multistage random sampling was used to select pregnant women and mothers of infants ⩽6 months old to interview at health facilities. Women were asked whether they had received free samples of substitutes for breast milk (including infant formula designed to meet the nutritional needs of infants from birth to 4 to 6 months of age, follow on formula designed to replace infant formula at the age of 4 to 6 months, and complementary foods for infants aged ⩽6 months), bottles, or teats. The source of the free sample and when it had been given to the women was also determined. 3 health workers were interviewed at each facility to assess whether the facility had received free samples, to determine how they had been used, and to determine whether gifts had been given to health workers by companies that manufactured or distributed breast milk substitutes. Compliance with the marketing code for information given to health workers was evaluated using a checklist. Setting: Health facilities in Dhaka, Bangladesh; Warsaw, Poland; Durban, South Africa; and Bangkok, Thailand. Subjects: 1468 pregnant women, 1582 mothers of infants aged ⩽6 months, and 466 health workers at 165 health facilities. Main outcome measures: Number of free samples received by pregnant women, mothers, and health workers; number of gifts given to health workers; and availability of information that violated the code in health facilities. Results: 97 out of 370 (26%) mothers in Bangkok reported receiving free samples of breast milk substitutes, infant formula, bottles, or teats compared with only 1 out of 385 mothers in Dhaka. Across the four cities from 3 out of 40 (8%) to 20 out of 40 (50%) health facilities had received free samples which were not being used for research or professional evaluation; from 2 out of 123 (2%) to 21 out of 119 (18%) health workers had received gifts from companies involved in the manufacturing or distribution of breast milk substitutes. From 6 out of 40 (15%) to 22 out of 39 (56%) health facilities information that violated the code had been provided by companies and was available to staff. Conclusion: Violations of the code were detected with a simple survey instrument in all of the four countries studied. Governmental and non-governmental agencies should monitor the prevalence of code violations using the simple methodology developed for this study.
Key messages
- A simple multistage random sampling procedure can be used to interview women and health professionals to assess whether violations of the international code of marketing of substitutes for breast milk are occurring
- 3050 women and 466 health professionals were interviewed at 165 health facilities in Bangladesh, Poland, South Africa, and Thailand
- 97 out of 370 mothers in Bangkok reported receiving free samples of breast milk substitutes, infant formula, bottles, or teats compared with only 1 out of 385 mothers in Dhaka. In Bangkok health workers reported that 20 out of 40 health facilities had also received free samples. Most free samples were distributed by health facilities
- In Warsaw 56% of facilities surveyed were found to have information available for health workers that had been provided by manufacturers or distributors of breast milk substitutes in contravention of the code; 18% of health workers in Warsaw had received free gifts from manufacturers
992.
Woodhead Mary Howard V. Davies Rex M. Brennan Mark A. Taylor 《Molecular biotechnology》1998,9(3):243-246
A method is described for isolating DNA of high molecular mass (Mr) from blackcurrant and other soft-fruit species. Following a hexacethylytimethyl ammonium bromide (CTAB)-based extraction procedure, samples are treated with a glycosidic hydrolase mixture and RNase, and then purified. The suitability of this DNA for Southern analysis and genomic-library construction is demonstrated. 相似文献
993.
994.
Eucomis (Family Hyacinthaceae) bulbs are greatly valued in traditionalmedicine for the treatment of a variety of ailments, predominantly thoseinvolving pain, fever and inflammation. The COX-1 assay was used to screenethanolic extracts prepared from the dried leaves, bulbs and roots of E. autumnalis (subspecies autumnalis) to determine the variation ofanti-inflammatory activity with age and season of harvest. Young plantswere found to have large amounts of COX-1 inhibitory activity, particularlyin the leaves. As the plant matured, greater activity was associated with thebulb and root extracts. The anti-inflammatory activity of the leaf, bulb androot extracts varied slightly throughout the year, with the greatest levelsdetected towards the end of the growing season, shortly before the onsetof dormancy. A seaweed application (Kelpak) decreased the anti-inflammatory activity of the leaf, bulb and root extracts, while increasedtemperature/increased light intensity had no significant effect on theCOX-1 inhibitory activity of the leaf extracts. The bulb extracts fromtreated plants harvested towards the end of the growing season showed asignificant decrease in anti-inflammatory activity, while the anti-inflammatory activity of the corresponding not root extracts increased. 相似文献
995.
The lipopolysaccharides (LPS) of most Helicobacter pylori strains contain complex carbohydrates known as Lewis antigens that are structurally related to the human blood group antigens. Investigations on the genetic determinants involved in the biosynthesis of Lewis antigens have led to the identification of the fucosyltransferases of H. pylori, which have substrate specificities distinct from the mammalian fucosyltransferases. Compared with its human host, H. pylori utilizes a different pathway to synthesize the difucosylated Lewis antigens, Lewis y. and Lewis b. Unique features in the H. pylori fucosyltransferase genes, including homopolymeric tracts mediating slipped-strand mispairing and the elements regulating translational frameshifting, enable H. pylori to produce variable LPS epitopes on its surface. These new findings have provided us with a basis to further examine the roles of molecular mimicry and phase variation of H. pylori Lewis antigen expression in both persistent infection and pathogenesis of this important human gastric pathogen. 相似文献
996.
Linkage between theMls locus and the chromosome 1 markersDip-1 andald was detected using two sets of recombinant inbred strains. Linkage betweenMls andDip-1 was confirmed in the fifth and sixth backcross generations of an incipient congenic strain. The AKXL data indicate that the gene order isDip-1-ald-Mls. The recombination frequency betweenald andMls is estimated to be 0.07 ±0.05, based on the AKXL data. The recombination frequency betweenDip-1 andMls is estimated to be 0.18 ±0.04, based on all the available data. 相似文献
997.
Sonoko Ogawa John D. Gordan Julia Taylor Dennis Lubahn Kenneth Korach Donald W. Pfaff 《Hormones and behavior》1996,30(4):487-494
Effects of gene products on reproductive behavior which are relatively direct include those of the estrogen receptor and progesterone receptor. For example, work with estrogen receptor-deficient (ERKO) female mice has extended previous evidence contributing to the neurochemical analysis of lordosis behavior. On the other hand, sex differences in behavior present a classic example of indirect effects of genes on behavior. Work with ERKO male mice shows the necessity of ER gene expression for normal masculinization of the brain. In particular, behavioral assay results distinguish apparent motivational performance of ERKO males from male mating reflexes: the former is similar to that of wild-type males in important respects, while the latter are deficient in ERKO males. The present paper first reviews a small number of clear genetic contributions to reproductive behaviors, and then reports one experiment pertinent to the interpretation of the behavioral status of ERKO male mice. 相似文献
998.
Crystal structures of mitochondrial processing peptidase reveal the mode for specific cleavage of import signal sequences 总被引:4,自引:0,他引:4
Taylor AB Smith BS Kitada S Kojima K Miyaura H Otwinowski Z Ito A Deisenhofer J 《Structure (London, England : 1993)》2001,9(7):615-625
BACKGROUND: Mitochondrial processing peptidase (MPP) is a metalloendopeptidase that cleaves the N-terminal signal sequences of nuclear-encoded proteins targeted for transport from the cytosol to the mitochondria. Mitochondrial signal sequences vary in length and sequence, but each is cleaved at a single specific site by MPP. The cleavage sites typically contain an arginine at position -2 (in the N-terminal portion) from the scissile peptide bond in addition to other distal basic residues, and an aromatic residue at position +1. Mitochondrial import machinery recognizes amphiphilic helical conformations in signal sequences. However, it is unclear how MPP specifically recognizes diverse presequence substrates. RESULTS: The crystal structures of recombinant yeast MPP and a cleavage-deficient mutant of MPP complexed with synthetic signal peptides have been determined. MPP is a heterodimer; its alpha and beta subunits are homologous to the core II and core I proteins, respectively, of the ubiquinol-cytochrome c oxidoreductase complex. Crystal structures of two different synthetic substrate peptides cocrystallized with the mutant MPP each show the peptide bound in an extended conformation at the active site. Recognition sites for the arginine at position -2 and the +1 aromatic residue are observed. CONCLUSIONS: MPP bound two mitochondrial import presequence peptides in extended conformations in a large polar cavity. The presequence conformations differ from the amphiphilic helical conformation recognized by mitochondrial import components. Our findings suggest that the presequences adopt context-dependent conformations through mitochondrial import and processing, helical for recognition by mitochondrial import machinery and extended for cleavage by the main processing component. 相似文献
999.
Global organellar proteomics 总被引:21,自引:0,他引:21
Cataloging the proteomes of single-celled microorganisms, cells, biological fluids, tissue and whole organisms is being undertaken at a rapid pace as advances are made in protein and peptide separation, detection and identification. For metazoans, subcellular organelles represent attractive targets for global proteome analysis because they represent discrete functional units, their complexity in protein composition is reduced relative to whole cells and, when abundant cytoskeletal proteins are removed, lower abundance proteins specific to the organelle are revealed. Here, we review recent literature on the global analysis of subcellular organelles and briefly discuss how that information is being used to elucidate basic biological processes that range from cellular signaling pathways through protein-protein interactions to differential expression of proteins in response to external stimuli. We assess the relative merits of the different methods used and discuss issues and future directions in the field. 相似文献
1000.
Site-specific cyclic nucleotide binding and dissociation of the holoenzyme of cAMP-dependent protein kinase 总被引:3,自引:0,他引:3
The photoaffinity reagent 8-azidoadenosine 3':5'-monophosphate (8-N3cAMP) was previously shown to modify a single tyrosine residue on the type II regulatory subunit of cAMP-dependent protein kinase (Kerlavage, A.R., and Taylor, S.S. (1980) J. Biol. Chem, 255, 8483-8488). In the present studies, the binding stoichiometries of type II holoenzyme for cAMP and 8-N3cAMP were determined using Millipore filtration assays in the absence (Assay A) and presence (Assay B) of 2 M NaCl and histone. The binding stoichiometry of holoenzyme for cAMP was 2 mol/mol with Assay A, and 4 mol/mol with assay B. The binding stoichiometry for 8-N3cAMP was 2 mol/mol with Assay B or with Assay A following photolysis of the holoenzyme:8-N3cAMP mixture. In the absence of photolysis, the binding stoichiometry for 8-N3cAMP was 0.4 mol/mol with Assay A. Both 8-N3cAMP and cAMP fully dissociated the holoenzyme. Holoenzyme, labeled with 8-N3[3H]cAMP on a preparative scale, incorporated 1 mol of 8-N3[3H]cAMP/mol of regulatory subunit (RII) monomer. The labeled RII was separated from catalytic subunit, cleaved with cyanogen bromide, and the resultant peptides were separated by high performance liquid chromatography. A single radioactive peptide was observed which had the same NH2 terminal residue and amino acid composition as the peptide obtained when dissociated RII was labeled with 8-N3cAMP. 相似文献