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71.
Kim J. Brolin Ribacke Alex J. van Duinen Helena Nordenstedt Jonas H?ijer Ragnhild Molnes Torunn Wigum Froseth AP Koroma Elisabeth Darj H?kon Angel Bolkan AnnaMia Ekstr?m 《PloS one》2016,11(2)
Background
As Sierra Leone celebrates the end of the Ebola Virus Disease (EVD) outbreak, we can begin to fully grasp its impact on already weak health systems. The EVD outbreak in West Africa forced many hospitals to close down or reduce their activity, either to prevent nosocomial transmission or because of staff shortages. The aim of this study is to assess the potential impact of EVD on nationwide access to obstetric care in Sierra Leone.Methods and Findings
Community health officers collected weekly data between January 2014—May 2015 on in-hospital deliveries and caesarean sections (C-sections) from all open facilities (public, private for-profit and private non-profit sectors) offering emergency obstetrics in Sierra Leone. This was compared to official data of EVD cases per district. Logistic and Poisson regression analyses were used to compute risk and rate estimates. Nationwide, the number of in-hospital deliveries and C-sections decreased by over 20% during the EVD outbreak. The decline occurred early on in the EVD outbreak and was mainly attributable to the closing of private not-for-profit hospitals rather than government facilities. Due to difficulties in collecting data in the midst of an epidemic, limitations of this study include some missing data points.Conclusions
Both the number of in-hospital deliveries and C-sections substantially declined shortly after the onset of the EVD outbreak. Since access to emergency obstetric care, like C-sections, is associated with decreased maternal mortality, many women are likely to have died due to the reduced access to appropriate care during childbirth. Future research on indirect health effects of health system breakdown should ideally be nationwide and continue also into the recovery phase. It is also important to understand the mechanisms behind the deterioration so that important health services can be reestablished. 相似文献72.
Ocellatin‐PT antimicrobial peptides: High‐resolution microscopy studies in antileishmania models and interactions with mimetic membrane systems 下载免费PDF全文
Mayara Oliveira Ana Georgina Gomes‐Alves Carla Sousa Mariela Mirta Marani Alexandra Plácido Nuno Vale Cristina Delerue‐Matos Paula Gameiro Selma A. S. Kückelhaus Ana M. Tomas José Roberto S. A. Leite Peter Eaton 《Biopolymers》2016,105(12):873-886
Although the mechanism of action of antimicrobial peptides (AMPs) is not clear, they can interact electrostatically with the cell membranes of microorganisms. New ocellatin‐PT peptides were recently isolated from the skin secretion of Leptodactylus pustulatus. The secondary structure of these AMPs and their effect on Leishmania infantum cells, and on different lipid surface models was characterized in this work. The results showed that all ocellatin‐PT peptides have an α‐helix structure and five of them (PT3, PT4, PT6 to PT8) have leishmanicidal activity; PT1 and PT2 affected the cellular morphology of the parasites and showed greater affinity for leishmania and bacteria‐mimicking lipid membranes than for those of mammals. The results show selectivity of ocellatin‐PTs to the membranes of microorganisms and the applicability of biophysical methods to clarify the interaction of AMPs with cell membranes. 相似文献
73.
Dung beetle species interactions and multifunctionality are affected by an experimentally warmed climate 下载免费PDF全文
While substantial effort has been invested in modelling changes in species distribution with climate change, less attention has been given to how climate warming will affect interactions among co‐occurring species, and the cascading functional consequences. In this study, realistic dung beetle communities were subjected to an experimental warming treatment and the net effect on the functions of dung decomposition (in terms of dung mass) and plant productivity (in terms of biomass production of ryegrass grown on soil from underneath the dung pats) were examined. A priori, we hypothesized that the largest tunneling species would be functionally dominant, and be differently affected by experimental warming compared to pat‐dwelling, smaller species. In terms of dung decomposition, the largest beetles did prove to be the functionally most important, with the qualitative pattern unaffected by experimental warming. In contrast, for plant productivity all species appeared equally important under ambient conditions. However, the effects of single species on plant productivity were reduced as temperature increased: In a warmed climate, a combination of both tunneling and pat‐dwelling species came the closest to returning ecosystem functioning to levels found in the ambient treatment. These results suggest different roles for different species, and highlight the importance of maintaining multiple species within an ecosystem – particularly when systems are perturbed. 相似文献
74.
75.
A PBX1 transcriptional network controls dopaminergic neuron development and is impaired in Parkinson's disease 下载免费PDF全文
J Carlos Villaescusa Bingsi Li Enrique M Toledo Pia Rivetti di Val Cervo Shanzheng Yang Simon RW Stott Karol Kaiser Saiful Islam Daniel Gyllborg Rocio Laguna‐Goya Michael Landreh Peter Lönnerberg Anna Falk Tomas Bergman Roger A Barker Sten Linnarsson Licia Selleri Ernest Arenas 《The EMBO journal》2016,35(18):1963-1978
76.
77.
Strejc Jan Kyselova Lucie Cadkova Anna Potocar Tomas Branyik Tomas 《Extremophiles : life under extreme conditions》2019,23(2):219-227
Extremophiles - Acidothermophilic bacteria of the genus Alicyclobacillus are frequent contaminants of fruit-based products. This study is the first attempt to characterize the physico-chemical... 相似文献
78.
79.
Rui Faria Pragya Chaube Hernn E. Morales Tomas Larsson Alan R. Lemmon Emily M. Lemmon Marina Rafajlovi Marina Panova Mark Ravinet Kerstin Johannesson Anja M. Westram Roger K. Butlin 《Molecular ecology》2019,28(6):1375-1393
Both classical and recent studies suggest that chromosomal inversion polymorphisms are important in adaptation and speciation. However, biases in discovery and reporting of inversions make it difficult to assess their prevalence and biological importance. Here, we use an approach based on linkage disequilibrium among markers genotyped for samples collected across a transect between contrasting habitats to detect chromosomal rearrangements de novo. We report 17 polymorphic rearrangements in a single locality for the coastal marine snail, Littorina saxatilis. Patterns of diversity in the field and of recombination in controlled crosses provide strong evidence that at least the majority of these rearrangements are inversions. Most show clinal changes in frequency between habitats, suggestive of divergent selection, but only one appears to be fixed for different arrangements in the two habitats. Consistent with widespread evidence for balancing selection on inversion polymorphisms, we argue that a combination of heterosis and divergent selection can explain the observed patterns and should be considered in other systems spanning environmental gradients. 相似文献
80.
Ana Laura Tomas Maria Alice Garcia Bento Leonardo Damian Mutti Fernando Jos Zara Laura Susana Lpez Greco 《Invertebrate Biology》2019,138(1):17-28
This study aims to analyze the functional anatomy of the male reproductive system in Neocaridina davidi, a very popular ornamental species of caridean shrimp. Mature males were cold‐anaesthetized and their reproductive systems were dissected for histological and histochemical analysis, while the spermatozoa and spermatophore wall ultrastructure were analyzed under transmission electron microscopy. The male reproductive system consisted of two coiled testes, which were continuous with the vasa deferentia. Testes were positioned on the dorsal side of the cephalothorax above the hepatopancreas, and comprised seminiferous tubules where spermatogenesis occurred. Each vas deferens (VD) was a long tube dorsolaterally positioned with respect to the hepatopancreas, and increased in diameter at the distal end. Three regions could be recognized in the VD: proximal, middle, and distal. The proximal region had a cylindrical epithelium with secretory cells. The middle region (or typhlosole) had a dorsal fold (or typhlosole) with a thick columnar epithelium and high secretory activity. The spermatophore was a continuous cord with three acellular layers, which were mainly characterized by the presence of neutral glycoconjugates and proteins. The sperm morphology was distinct from the inverted cup‐shaped spermatozoa observed in the majority of caridean shrimps. The spermatozoa in specimens of N. davidi were spherical in shape, with a cross‐striated, single, short spike, and arranged in clusters of three or four sperm cells. The composition of the spermatophore, and the arrangement and form of the spermatozoa, seem to be unique in comparison to other species of Caridea. 相似文献