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91.
BackgroundThe role of breast screening in breast cancer mortality declines is debated. Screening impacts cancer mortality through decreasing the number of advanced cancers with poor diagnosis, while cancer treatment works through decreasing the case-fatality rate. Hence, reductions in cancer death rates thanks to screening should directly reflect reductions in advanced cancer rates. We verified whether in breast screening trials, the observed reductions in the risk of breast cancer death could be predicted from reductions of advanced breast cancer rates.ResultsThe observed and predicted RR of breast cancer death were 0.72 (0.56–0.94) and 0.98 (0.77–1.24) in the HIP trial, and 0.79 (0.78–1.01) and 0.90 (0.80–1.01) in the Age trial. In the TCT, the observed RR was 0.73 (0.62–0.87), while the predicted RR was 0.89 (0.75–1.05) if overdiagnosis was assumed to be negligible and 0.83 (0.70–0.97) if extra cancers were excluded.ConclusionsIn breast screening trials, factors other than screening have contributed to reductions in the risk of breast cancer death most probably by reducing the fatality of advanced cancers in screening groups. These factors were the better management of breast cancer patients and the underreporting of breast cancer as the underlying cause of death. Breast screening trials should publish stage-specific fatalities observed in each group. 相似文献
92.
Olga Joos Agbessi Amouzou Romesh Silva Benjamin Banda Lois Park Jennifer Bryce Mercy Kanyuka RMM Malawi working group 《PloS one》2016,11(1)
Background
Malawi ratified a compulsory birth and death registration system in 2009. Until it captures complete coverage of vital events, Malawi relies on other data sources to calculate mortality estimates. We tested a community-based method to estimate annual under-five mortality rates (U5MR) through the Real-Time Monitoring of Under-Five Mortality (RMM) project in Malawi. We implemented RMM in two phases, and conducted an independent evaluation of phase one after 21 months of implementation. We present results of the phase two validation that covers the full project time span, and compare the results to those of the phase one validation.Methods and Findings
We assessed the completeness of the counts of births and deaths and the accuracy of disaggregated U5MR from the community-based method against a retrospective full pregnancy history for rolling twelve-month periods after the independent evaluation. We used full pregnancy histories collected through household interviews carried out between November 2013 and January 2014 as the validation data source. Health Surveillance Agents (HSAs) across the 160 catchment areas submitted routine reports on pregnancies, births, and deaths consistently. However, for the 15-month implementation period post-evaluation, average completeness of birth event reporting was 76%, whereas average completeness of death event reporting was 67% relative to that expected from a comparable pregnancy history. HSAs underestimated the U5MR by an average of 21% relative to that estimated from a comparable pregnancy history.Conclusions
On a medium scale, the community-based RMM method in Malawi produced substantial underestimates of annualized U5MR relative to those obtained from a full pregnancy history, despite the additional incentives and quality-control activities. We were not able to achieve an optimum level of incentive and support to make the system work while ensuring sustainability. Lessons learned from the implementation of RMM can inform programs supporting community-based interventions through HSAs in Malawi. 相似文献93.
Fidele Ngabo Mercy Mvundura Lauren Gazley Maurice Gatera Celse Rugambwa Eugene Kayonga Yvette Tuyishime Jeanne Niyibaho Jason M. Mwenda Philippe Donnen Philippe Lepage Agnes Binagwaho Deborah Atherly 《PloS one》2016,11(2)
Background
Diarrhea is one of the leading causes of childhood morbidity and mortality. Hospitalization for diarrhea can pose a significant burden to health systems and households. The objective of this study was to estimate the economic burden attributable to hospitalization for diarrhea among children less than five years old in Rwanda. These data can be used by decision-makers to assess the impact of interventions that reduce diarrhea morbidity, including rotavirus vaccine introduction.Methods
This was a prospective costing study where medical records and hospital bills for children admitted with diarrhea at three hospitals were collected to estimate resource use and costs. Hospital length of stay was calculated from medical records. Costs incurred during the hospitalization were abstracted from the hospital bills. Interviews with the child’s caregivers provided data to estimate household costs which included transport costs and lost income. The portion of medical costs borne by insurance and household were reported separately. Annual economic burden before and after rotavirus vaccine introduction was estimated by multiplying the reported number of diarrhea hospitalizations in public health centers and district hospitals by the estimated economic burden per hospitalization. All costs are presented in 2014 US$.Results
Costs for 203 children were analyzed. Approximately 93% of the children had health insurance coverage. Average hospital length of stay was 5.3 ± 3.9 days. Average medical costs for each child for the illness resulting in a hospitalization were $44.22 ± $23.74 and the total economic burden was $101, of which 65% was borne by the household. For households in the lowest income quintile, the household costs were 110% of their monthly income. The annual economic burden to Rwanda attributable to diarrhea hospitalizations ranged from $1.3 million to $1.7 million before rotavirus vaccine introduction.Conclusion
Households often bear the largest share of the economic burden attributable to diarrhea hospitalization and the burden can be substantial, especially for households in the lowest income quintile. 相似文献94.
95.
96.
Trends in forest condition,threats and conservation action as derived from participatory monitoring in coastal Kenya
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Paul K. Ndang'ang'a Fred M. Barasa Mercy N. Kariuki Paul Muoria 《African Journal of Ecology》2016,54(1):76-86
The coastal forests of Kenya are conservation priorities hosting high levels of biodiversity. Monitoring of biodiversity in these forests is therefore necessary to understand and reverse negative trends in good time. Using the Important Bird Area (IBA) monitoring framework, a participatory approach, state (habitat condition), pressure (threats) and response (conservation action) indicators of twelve coastal Kenya forest IBAs were assessed from 2004 to 2011. Trends for these indicators were assessed at six sites for which sufficient data existed: Arabuko‐Sokoke, Dakatcha Woodlands, Gede Ruins, Lower Tana River, Shimba Hills and Taita Hills, and baselines were described for remaining six. Changes were always small, but state deteriorated in Gede, Lower Tana and Shimba Hills, remained the same (unfavourable) in Arabuko‐Sokoke and Dakatcha, and improved in Taita Hills. Pressure reduced in Arabuko‐Sokoke, Dakatcha and Taita Hills, deteriorated in Lower Tana and Shimba Hills and remained the same (medium) in Gede. Response improved in Dakatcha, remained the same (medium) in Shimba Hills, and deteriorated in the rest. As there was an apparent overall deterioration in the forests assessed, improved management of the protected sites and increased conservation action through community engagement around protected areas and within the nonprotected IBAs are recommended. 相似文献
97.
Mathieu Coulis Stephan Hättenschwiler Sylvain Coq Jean-François David 《Ecosystems》2016,19(6):1104-1115
In many terrestrial ecosystems, large amounts of leaf litter are consumed by macroarthropods. Most of it is deposited as faeces that are easily transferred into deeper soil layers. However, the decomposition of this large pool of organic matter remains poorly studied. We addressed the question of how leaf litter transformation into macroarthropod faeces, and their burial in the soil, affect organic matter decomposition in a Mediterranean dry shrubland. We compared mass loss of intact leaf litter of two dominant shrub species (Quercus coccifera, Cistus albidus) with that of leaf litter-specific faeces from the abundant millipede Ommatoiulus sabulosus. Leaf litter and faeces were exposed in the field for 1 year, either on the soil surface or buried at 5 cm soil depth. Chemical and physical quality of faeces differed strongly from that of leaf litter, but distinctively between the two shrub species. On the soil surface, faeces decomposed faster than intact leaf litter in Quercus, but at similar rates in Cistus. When buried in the soil, faeces and leaf litter decomposed at similar rates in either species, but significantly faster compared to the soil surface, most likely because of higher moisture within the soil enhancing microbial activity. The combined effects of leaf litter transformation into faeces and their subsequent burial in the topsoil led to a 1.5-fold increase in the annual mass loss. These direct and indirect macroarthropod effects on ecosystem-scale decomposition are likely more widespread than currently acknowledged, and may play a particularly important role in drought-influenced ecosystems. 相似文献
98.
Global Salmonidae introductions reveal stronger ecological effects of changing intraspecific compared to interspecific diversity
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The introduction of organisms within the native range of wild conspecifics is a widespread phenomenon and locally modifies patterns in intraspecific diversity. However, our knowledge of the resulting ecological effects, as opposed to those caused by invasion‐induced changes in interspecific diversity, is still limited. Here, we investigated the ecological effects of native and non‐native invaders across levels of biological organisations and recipient organisms using the global and long history introductions of salmonids. Our meta‐analysis demonstrated that the global effects of native species introductions exceeded those induced by non‐native invaders. The impacts of native invaders were primarily manifested at the individual level on wild conspecifics, but remained largely unexplored on other native organisms and at the community and ecosystem levels. Overlooked and poorly appreciated, quantifying the impacts of native invaders has important implications because human‐assisted introductions of domesticated organisms are ubiquitous and likely to proliferate in the future. 相似文献
99.
Jaroslav Slamecka Lilia Salimova Steven McClellan Mathieu van Kelle Debora Kehl Javier Laurini 《Cell cycle (Georgetown, Tex.)》2016,15(2):234-249
Amniotic fluid stem cells (AFSC) represent an attractive potential cell source for fetal and pediatric cell-based therapies. However, upgrading them to pluripotency confers refractoriness toward senescence, higher proliferation rate and unlimited differentiation potential. AFSC were observed to rapidly and efficiently reacquire pluripotency which together with their easy recovery makes them an attractive cell source for reprogramming. The reprogramming process as well as the resulting iPSC epigenome could potentially benefit from the unspecialized nature of AFSC. iPSC derived from AFSC also have potential in disease modeling, such as Down syndrome or β-thalassemia. Previous experiments involving AFSC reprogramming have largely relied on integrative vector transgene delivery and undefined serum-containing, feeder-dependent culture. Here, we describe non-integrative oriP/EBNA-1 episomal plasmid-based reprogramming of AFSC into iPSC and culture in fully chemically defined xeno-free conditions represented by vitronectin coating and E8 medium, a system that we found uniquely suited for this purpose. The derived AF-iPSC lines uniformly expressed a set of pluripotency markers Oct3/4, Nanog, Sox2, SSEA-1, SSEA-4, TRA-1-60, TRA-1-81 in a pattern typical for human primed PSC. Additionally, the cells formed teratomas, and were deemed pluripotent by PluriTest, a global expression microarray-based in-silico pluripotency assay. However, we found that the PluriTest scores were borderline, indicating a unique pluripotent signature in the defined condition. In the light of potential future clinical translation of iPSC technology, non-integrating reprogramming and chemically defined culture are more acceptable. 相似文献
100.
Twenty‐three resin samples have been obtained by tapping from individual Pinus pinaster adult trees grown in Corsica and submitted to acido‐basic partition. Identification and quantitative determination of resin acids has been carried out using 13C‐NMR spectroscopy following a method developed by our group. The main components were dehydroabietic acid (up to 37.6 %), levopimaric acid (up to 35.5 %) and abietic acid (up to 24.7 %). A lignan, pinoresinol, has been identified in some samples. Within the 23 compositions, submitted to k‐means analysis and Principal Component Analysis, two clusters have been perfectly differentiated, whose compositions were dominated by dehydroabietic acid (Group I, M=23.5 %, SD=6.3) and levopimaric acid (Group II, M=21.2 %; SD=6.2), respectively. Both compositions have been observed in the three locations of harvest. 相似文献