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1.
Goldman AS Guisinger VH Aikins M Amarillo ML Belizario VY Garshong B Gyapong J Kabali C Kamal HA Kanjilal S Kyelem D Lizardo J Malecela M Mubyazi G Nitièma PA Ramzy RM Streit TG Wallace A Brady MA Rheingans R Ottesen EA Haddix AC 《PLoS neglected tropical diseases》2007,1(1):e67
Background
Because lymphatic filariasis (LF) elimination efforts are hampered by a dearth of economic information about the cost of mass drug administration (MDA) programs (using either albendazole with diethylcarbamazine [DEC] or albendazole with ivermectin), a multicenter study was undertaken to determine the costs of MDA programs to interrupt transmission of infection with LF. Such results are particularly important because LF programs have the necessary diagnostic and treatment tools to eliminate the disease as a public health problem globally, and already by 2006, the Global Programme to Eliminate LF had initiated treatment programs covering over 400 million of the 1.3 billion people at risk.Methodology/Principal Findings
To obtain annual costs to carry out the MDA strategy, researchers from seven countries developed and followed a common cost analysis protocol designed to estimate 1) the total annual cost of the LF program, 2) the average cost per person treated, and 3) the relative contributions of the endemic countries and the external partners. Costs per person treated ranged from $0.06 to $2.23. Principal reasons for the variation were 1) the age (newness) of the MDA program, 2) the use of volunteers, and 3) the size of the population treated. Substantial contributions by governments were documented – generally 60%–90% of program operation costs, excluding costs of donated medications.Conclusions/Significance
MDA for LF elimination is comparatively inexpensive in relation to most other public health programs. Governments and communities make the predominant financial contributions to actual MDA implementation, not counting the cost of the drugs themselves. The results highlight the impact of the use of volunteers on program costs and provide specific cost data for 7 different countries that can be used as a basis both for modifying current programs and for developing new ones. 相似文献2.
3.
MJ Müller MP Mendon?a IR Oliveira LPL de Oliveira VLS Valente VH Valiati 《Neotropical Entomology》2012,41(2):112-120
We describe for the first time the sexual behavior and the courtship song of males of the African fly Zaprionus indianus (Gupta), a recent invader of South America. The male courtship song is formed by monocyclic pulses and the courtship behavior is simple when compared to that of species of Drosophila. Two interpulse interval (IPI) distributions were observed: pre-mounting and mounting. No significant difference was observed between the pre-mounting IPIs of males that descended from three geographical populations from South America. We also observed the songs produced by females and the homosexual behavior exhibited by males. A sequence of bursts is produced by females as a refusal signal against males, while males emit a characteristic song that identifies sex genus, which differs from the courtship song. The short courtship and mating latencies recorded reveal vigorous males and receptive females, respectively. 相似文献
4.
The alcohol dehydrogenase (Adh) gene was isolated from Drosophila simulans
and D. mauritiana, and the DNA sequence of a 4.6-kb region, containing the
structural gene and flanking sequence, was determined for each. These
sequences were compared with the Adh region of D. melanogaster to
characterize changes that occur in the Drosophila genome during evolution
and to identify conserved sequences of functional importance. Drosophila
simulans and D. mauritiana Adh are organized in a manner similar to that of
D. melanogaster Adh, including the presence of two promoters for the single
Adh gene. This study identified conserved flanking elements that, in
conjunction with other studies, suggest regions that may be involved in the
control of Adh expression. Inter- and intraspecies comparisons revealed
differences in the kinds of sequence changes that have accumulated.
Sequence divergence in and around the Adh gene was used to assess inter-
and intraspecies evolutionary relationships. Finally, there appears to be
an unrelated structural gene located directly 3' of the Adh transcribed
region.
相似文献
5.
Mary M. Guisinger Timothy W. Chumley Jennifer V. Kuehl Jeffrey L. Boore Robert K. Jansen 《Journal of molecular evolution》2010,70(2):149-166
Plastid genomes of the grasses (Poaceae) are unusual in their organization and rates of sequence evolution. There has been
a recent surge in the availability of grass plastid genome sequences, but a comprehensive comparative analysis of genome evolution
has not been performed that includes any related families in the Poales. We report on the plastid genome of Typha latifolia, the first non-grass Poales sequenced to date, and we present comparisons of genome organization and sequence evolution within
Poales. Our results confirm that grass plastid genomes exhibit acceleration in both genomic rearrangements and nucleotide
substitutions. Poaceae have multiple structural rearrangements, including three inversions, three genes losses (accD, ycf1, ycf2), intron losses in two genes (clpP, rpoC1), and expansion of the inverted repeat (IR) into both large and small single-copy regions. These rearrangements are restricted
to the Poaceae, and IR expansion into the small single-copy region correlates with the phylogeny of the family. Comparisons
of 73 protein-coding genes for 47 angiosperms including nine Poaceae genera confirm that the branch leading to Poaceae has
significantly accelerated rates of change relative to other monocots and angiosperms. Furthermore, rates of sequence evolution
within grasses are lower, indicating a deceleration during diversification of the family. Overall there is a strong correlation
between accelerated rates of genomic rearrangements and nucleotide substitutions in Poaceae, a phenomenon that has been noted
recently throughout angiosperms. The cause of the correlation is unknown, but faulty DNA repair has been suggested in other
systems including bacterial and animal mitochondrial genomes. 相似文献
6.
Zhengqiu Cai Mary Guisinger Hyi-Gyung Kim Elizabeth Ruck John C. Blazier Vanity McMurtry Jennifer V. Kuehl Jeffrey Boore Robert K. Jansen 《Journal of molecular evolution》2008,67(6):696-704
The plastid genome of Trifolium subterraneum is 144,763 bp, about 20 kb longer than those of closely related legumes, which also lost one copy of the large inverted repeat
(IR). The genome has undergone extensive genomic reconfiguration, including the loss of six genes (accD, infA, rpl22, rps16, rps18, and ycf1) and two introns (clpP and rps12) and numerous gene order changes, attributable to 14–18 inversions. All endpoints of rearranged gene clusters are flanked
by repeated sequences, tRNAs, or pseudogenes. One unusual feature of the Trifolium
subterraneum genome is the large number of dispersed repeats, which comprise 19.5% (ca. 28 kb) of the genome (versus about 4% for other
angiosperms) and account for part of the increase in genome size. Nine genes (psbT, rbcL, clpP, rps3, rpl23, atpB, psbN, trnI-cau, and ycf3) have also been duplicated either partially or completely. rpl23 is the most highly duplicated gene, with portions of this gene duplicated six times. Comparisons of the Trifolium plastid genome with the Plant Repeat Database and searches for flanking inverted repeats suggest that the high incidence
of dispersed repeats and rearrangements is not likely the result of transposition. Trifolium has 19.5 kb of unique DNA distributed among 160 fragments ranging in size from 30 to 494 bp, greatly surpassing the other
five sequenced legume plastid genomes in novel DNA content. At least some of this unique DNA may represent horizontal transfer
from bacterial genomes. These unusual features provide direction for the development of more complex models of plastid genome
evolution.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
We describe here a new method for specific staining of mast cells using ferroin. Different hamster tissues were fixed in 4% formalin and processed for paraffin embedding. Sections were stained with hematoxylin followed by ferroin acidified with 2.5 N sulfuric acid to pH 4.0. Mast cells stained an intense orange color that contrasted markedly with bluish violet nuclei. High contrast was also observed when ferroin colored sections were counterstained with light green instead of hematoxylin. To evaluate the specificity of the stain, hamster cheek pouch sections were stained with toluidine blue, alcian blue-safranin O, and ferroin. Quantitative evaluation of mast cells stained with the three techniques showed no statistical difference. The simplicity and selectivity of this method is sufficient for image analysis of mast cells. 相似文献
8.
The ultrastructure of root cap columella cells was studied by morphometric analysis in wild-type, a reduced-starch mutant, and a starchless mutant of Arabidopsis grown in microgravity (F-microgravity) and compared to ground 1g (G-1g) and flight 1g (F-1g) controls. Seedlings of the wild-type and reduced-starch mutant that developed during an experiment on the Space Shuttle (both the F-microgravity samples and the F-lg control) exhibited a decreased starch content in comparison to the G-1g control. These results suggest that some factor associated with spaceflight (and not microgravity per se) affects starch metabolism. Elevated levels of ethylene were found during the experiments on the Space Shuttle, and analysis of ground controls with added ethylene demonstrated that this gas was responsible for decreased starch levels in the columella cells. This is the first study to use an on-board centrifuge as a control when quantifying starch in spaceflight-grown plants. Furthermore, our results show that ethylene levels must be carefully considered and controlled when designing experiments with plants for the International Space Station. 相似文献
9.
Plastid genomes in the flowering plant family Geraniaceae are known to be highly rearranged based on complete sequences representing the four major genera Erodium, Geranium, Monsonia, and Pelargonium. In this paper we report on the genome sequence of a second species of Erodium, E. carvifolium, representing the second major clade (clade II) in the phylogeny of this genus. Comparison of this genome sequence to the previously published sequence of E. texanum from clade I demonstrates that the plastid genomes of these two species encode the same number of proteins but differ greatly in their relative degree of rearrangement; 14 kb of additional sequence in E. texanum contains complex repeats associated with rearrangement endpoints, whereas the plastid genome of E. carvifolium is streamlined at 116 kb and displays no unique alterations in gene order. Furthermore, these species from both major clades of Erodium contain intact NADH dehydrogenase (ndh) genes, but the 11 ndh genes are represented as pseudogenes in a small clade of 13 species. It is unclear whether plastid-encoded ndh genes have been lost entirely or functionally transferred to the nucleus. This is the third report of the absence of functional ndh genes, and the current study describes the most recent loss of these genes among photosynthetic seed plants and the second such loss among angiosperms. The other ndh losses from Pinaceae/Gnetales and Orchidaceae are much more ancient. Comparative biochemistry between Erodium species with and without plastid-encoded ndh genes may elucidate changes in photosynthetic function and the role of the Ndh complex. 相似文献
10.
We describe here a new method for specific staining of mast cells using ferroin. Different hamster tissues were fixed in 4% formalin and processed for paraffin embedding. Sections were stained with hematoxylin followed by ferroin acidified with 2.5 N sulfuric acid to pH 4.0. Mast cells stained an intense orange color that contrasted markedly with bluish violet nuclei. High contrast was also observed when ferroin colored sections were counterstained with light green instead of hematoxylin. To evaluate the specificity of the stain, hamster cheek pouch sections were stained with toluidine blue, alcian blue-safranin O, and ferroin. Quantitative evaluation of mast cells stained with the three techniques showed no statistical difference. The simplicity and selectivity of this method is sufficient for image analysis of mast cells. 相似文献