34 research outputs found
Characteristics of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) rRNA genes of Apis mellifera (Insecta: Hymenoptera): structure, organization, and retrotransposable elements
As an accompanying manuscript to the release of the honey bee genome, we report the entire sequence of the nuclear (18S, 5.8S, 28S and 5S) and mitochondrial (12S and 16S) ribosomal RNA (rRNA)-encoding gene sequences (rDNA) and related internally and externally transcribed spacer regions of Apis mellifera (Insecta: Hymenoptera: Apocrita). Additionally, we predict secondary structures for the mature rRNA molecules based on comparative sequence analyses with other arthropod taxa and reference to recently published crystal structures of the ribosome. In general, the structures of honey bee rRNAs are in agreement with previously predicted rRNA models from other arthropods in core regions of the rRNA, with little additional expansion in non-conserved regions. Our multiple sequence alignments are made available on several public databases and provide a preliminary establishment of a global structural model of all rRNAs from the insects. Additionally, we provide conserved stretches of sequences flanking the rDNA cistrons that comprise the externally transcribed spacer regions (ETS) and part of the intergenic spacer region (IGS), including several repetitive motifs. Finally, we report the occurrence of retrotransposition in the nuclear large subunit rDNA, as R2 elements are present in the usual insertion points found in other arthropods. Interestingly, functional R1 elements usually present in the genomes of insects were not detected in the honey bee rRNA genes. The reverse transcriptase products of the R2 elements are deduced from their putative open reading frames and structurally aligned with those from another hymenopteran insect, the jewel wasp Nasonia (Pteromalidae). Stretches of conserved amino acids shared between Apis and Nasonia are illustrated and serve as potential sites for primer design, as target amplicons within these R2 elements may serve as novel phylogenetic markers for Hymenoptera. Given the impending completion of the sequencing of the Nasonia genome, we expect our report eventually to shed light on the evolution of the hymenopteran genome within higher insects, particularly regarding the relative maintenance of conserved rDNA genes, related variable spacer regions and retrotransposable elements
Track D Social Science, Human Rights and Political Science
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd
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Understanding low uptake of contraceptives in resource-limited settings: a mixed-methods study in rural Burundi
Background: Family planning can reduce deaths, improve health, and facilitate economic development in resource-limited settings. Yet, modern contraceptive methods are often underused. This mixed-methods study, conducted in rural Burundi, sought to explain low uptake of contraceptives by identifying utilization barriers. Results may inform development of family planning interventions in Burundi and elsewhere. Methods: We investigated uptake of contraceptives among women of reproductive age in two rural districts of Burundi, using an explanatory sequential, mixed-methods research design. We first assessed availability and utilization rates of modern contraceptives through a facility-based survey in 39 health clinics. Barriers to uptake of contraceptives were then explored through qualitative interviews (N = 10) and focus groups (N = 7). Results: Contraceptives were generally available in the 39 clinics studied, yet uptake of family planning averaged only 2.96%. Greater uptake was positively associated with the number of health professionals engaged and trained in family planning service provision, and with the number of different types of contraceptives available. Four uptake barriers were identified: (1) lack of providers to administer contraception, (2) lack of fit between available and preferred contraceptive methods, (3) a climate of fear surrounding contraceptive use, and (4) provider refusal to offer family planning services. Conclusions: Where resources are scarce, availability of modern contraceptives alone will likely not ensure uptake. Interventions addressing multiple uptake barriers simultaneously have the greatest chance of success. In rural Burundi, examples are community distribution of contraceptive methods, public information campaigns, improved training for health professionals and community health workers, and strengthening of the health infrastructure. Electronic supplementary material The online version of this article (doi:10.1186/s12913-017-2144-0) contains supplementary material, which is available to authorized users
Additional file 4: of Understanding low uptake of contraceptives in resource-limited settings: a mixed-methods study in rural Burundi
Qualitative interview guide for health facility managers. (DOCX 13 kb