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91.
92.
Sarah E. Rutstein Mina C. Hosseinipour Deborah Kamwendo Alice Soko Memory Mkandawire Andrea K. Biddle William C. Miller Morris Weinberger Stephanie B. Wheeler Abdoulaye Sarr Sundeep Gupta Frank Chimbwandira Reuben Mwenda Steve Kamiza Irving Hoffman Ronald Mataya 《PloS one》2015,10(4)
Objectives
To evaluate the feasibility and effectiveness of dried blood spots (DBS) use for viral load (VL) monitoring, describing patient outcomes and programmatic challenges that are relevant for DBS implementation in sub-Saharan Africa.Methods
We recruited adult antiretroviral therapy (ART) patients from five district hospitals in Malawi. Eligibility reflected anticipated Ministry of Health VL monitoring criteria. Testing was conducted at a central laboratory. Virological failure was defined as >5000 copies/ml. Primary outcomes were program feasibility (timely result availability and patient receipt) and effectiveness (second-line therapy initiation).Results
We enrolled 1,498 participants; 5.9% were failing at baseline. Median time from enrollment to receipt of results was 42 days; 79.6% of participants received results within 3 months. Among participants with confirmed elevated VL, 92.6% initiated second-line therapy; 90.7% were switched within 365 days of VL testing. Nearly one-third (30.8%) of participants with elevated baseline VL had suppressed (<5,000 copies/ml) on confirmatory testing. Median period between enrollment and specimen testing was 23 days. Adjusting for relevant covariates, participants on ART >4 years were more likely to be failing than participants on therapy 1–4 years (RR 1.7, 95% CI 1.0-2.8); older participants were less likely to be failing (RR 0.95, 95% CI 0.92-0.98). There was no difference in likelihood of failure based on clinical symptoms (RR 1.17, 95% CI 0.65-2.11).Conclusions
DBS for VL monitoring is feasible and effective in real-world clinical settings. Centralized DBS testing may increase access to VL monitoring in remote settings. Programmatic outcomes are encouraging, especially proportion of eligible participants switched to second-line therapy. 相似文献93.
Within the framework of our study, we assessed the nodule occupancy of a mixture of various strains of rhizobia to inoculate
several provenances of Acacia senegal and Acacia nilotica. The first part of the experiment was carried out under greenhouse conditions where the plants were cultivated in polyvinyl
chloride tubes containing an unsterilized Sangalkam soil low in organic matter and nitrogen. The results showed that 4 and
8 months after sowing, rhizobial strains CIRADF 306 and CIRADF 300 were mainly present in nodules of A. nilotica and A. senegal, respectively. After transferring the seedlings to the more fertile soil in Bel Air field station, the molecular analysis
of the nodules showed that strain CIRADF 306 was absent from the nodules of A.
nilotica, whereas strain CIRADF 305 which occurred only at low nodule occupancy in the nursery, predominated in the field conditions.
On the other hand, strain CIRADF 300 occurred in the majority of the nodules from the various provenances of A. senegal. These results demonstrated actual interaction between inoculated rhizobial strains, soil type and host plant genotype in
terms of competitiveness, nodulation and symbiotic nitrogen fixation. 相似文献
94.
Sarró MI García AM Moreno DA Montero F 《Journal of industrial microbiology & biotechnology》2007,34(6):433-441
The aim of the present research was to study the biofilms developed in a Spanish nuclear power plant and their ability to
entrap radionuclides. In order to carry this out, a bioreactor, which was then submerged in a spent nuclear fuel pool, was
designed. To characterise the biofilm on two different metallic materials (stainless steel and titanium), standard culture
microbiological methods and molecular biology tools, as well as epifluorescence and scanning electron microscopy were used.
The bacterial composition of the biofilm belongs to several phylogenetic groups (α, β, and γ-Proteobacteria, Actinobacteridae, and Firmicutes). The radioactivity of the biofilms was measured by gamma-ray spectrometry. Biofilms were able to retain radionuclides from
radioactive water, especially 60Co. The potential use of these biofilms in bioremediation of radioactive water is discussed. 相似文献
95.
Kelly A. Jaenecke Paul C. Banko Robert W. Peck Zee Sarr Nicholas Shema 《Restoration Ecology》2024,32(3):e14033
Long-term ecological studies are invaluable for detecting changes over time. Forest restoration has been a conservation priority in Hawaiʻi, where invasive species have negatively impacted native bird habitat. During 1993–1994, a study was conducted of Hawaiʻi ʻelepaio (Chasiempis sandwichensis) nest site selection and forest composition in mesic montane forest along Mauna Loa Road in Hawaiʻi Volcanoes National Park. We returned to the site and repeated the methods used in the earlier study to record Hawaiʻi ʻelepaio nest site selection (tree species, tree and nest height, and tree girth [diameter at breast height, DBH]) from 2015 to 2017, and measured forest composition (tree density, relative abundance, height, and DBH) in 2019. Three times as many nests were found in ʻaʻaliʻi (Dodonaea viscosa) as in koa (Acacia koa) in both time periods. Heights of koa and ʻaʻaliʻi did not change, but their DBH increased over time. The relative height of nests in ʻaʻaliʻi trees did not change, but nests in koa were placed higher in the crown during the later study. Overall tree density increased from 1,619 (95% confidence interval [CI] = 1,499–1,740) trees/ha to 2,583 (95% CI = 2,176–3,096) trees/ha. Koa relative abundance was 53% of total trees earlier and 45% later, ʻaʻaliʻi remained at 47%, and māmane (Sophora chrysophylla) increased from 0 to 8% over time. Our results indicate that changes in forest composition affect nesting behavior, but in ways that are not necessarily simple or consistent. 相似文献
96.
97.
We studied riparian forests along mountain streams in four large watersheds of western Oregon and far northern California,
USA, to better understand the multiscale controls on woody riparian vegetation in a geographically complex region. In each
of the four-study watersheds, we sampled woody riparian vegetation in161-ha sampling reaches that straddled the stream channel.
Within each hectare, we sampled riparian vegetation and local environmental factors in 40 m2 sampling plots arrayed along topographic transects. We also surveyed natural disturbance gaps in 6 ha in each watershed to
explore the effects of fine scale disturbance on species distributions. We compared species composition across our study watersheds
and used Nonmetric Multidimensional Scaling (NMS) and chi-squared analyses to compare the relative importance of landscape
scale climate variables and local topographic and disturbance variables in explaining species distributions at sampling plot
and hectare scales.
We noted substantial turnover in the riparian flora across the region, with greatest numbers of unique species in watersheds
at the ends of the regional gradient. In NMS ordinations at both scales, variation in woody riparian species composition showed
strongest correlations with climatic variables and Rubus spectabilis cover, but the latter was only an important factor in the two northern watersheds. At the smaller scale, topographic variables
were also important. Chi-squared analyses confirmed that more species showed landscape scale habitat preferences (watershed
associations) than associations with topographic position (94.7% vs. 42.7% of species tested) or gap versus forest setting
(94.7% vs. 24.6% of species tested). The woody riparian flora of western Oregon shows important biogeographic variation; species
distributions showed strong associations with climatic variables, which were the primary correlates of compositional change
between riparian sites at both scales analyzed. Additional local variation in composition was explained by measures of topography
and disturbance. 相似文献
98.
We report a case of preputial myiasis in a child who presented with painful penile swelling suggestive of balanoposthitis. Treatment consisted of manual extraction of the worm followed by circumcision. Parasitologic study of the worm revealed a stage-three larva of Cordylobia anthropophaga. Through this case report and a review of the literature, we discuss the epidemiologic, diagnostic and therapeutic features of this disease. 相似文献
99.
Abstract: The Spanish town of Galve (Teruel) is notable because of the abundance of Upper Jurassic and, especially, Lower Cretaceous vertebrates recorded there. Although most groups have been studied in detail, information on turtles is very limited even though the material is relatively abundant. So far, no turtle taxa have been identified at the generic level. The only Lower Cretaceous articulated specimen from Galve is analysed here. It is identified as a representative of Cryptodira, Galvechelone lopezmartinezae gen. et sp. nov. Galvechelone lopezmartinezae is determined as a taxon belonging to the node that groups the turtles traditionally assigned to ‘Macrobaenidae’ and ‘Sinemydidae’, and other taxa such as the members of Panchelonioidea. This node, very abundant in the Lower Cretaceous of Asia, and with a broad subsequent distribution, has recently been recognized in the Lower Cretaceous of Europe. The diversity of basal members of Eucryptodira in the European Late Jurassic (represented by Thalassemydidae, Plesiochelyidae and Eurysternidae) was high. Owing to a relative scarcity of well‐preserved early Cretaceous turtles from Europe, the knowledge of this group of reptiles is limited. The study of the new turtle from Galve, together with the recently described Hoyasemys jimenezi, and the recently completed review of the enigmatic Chitracephalus dumonii demonstrate that members of the cryptodiran node grouping ‘Macrobaenidae’, ‘Sinemydidae’ and Panchelonioidea were also very diverse in this period. 相似文献
100.
Lobna Gaayeb Jean Biram Sarr Mamadou O. Ndiath Jean-Baptiste Hanon Anne-Sophie Debrie Modou Seck Anne-Marie Schacht Franck Remoué Emmanuel Hermann Gilles Riveau 《PloS one》2012,7(10)