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1.
Naima Maouche Nadia Ktari Idriss Bakas Najla Fourati Chouki Zerrouki Mahamadou Seydou François Maurel Mohammed Mehdi Chehimi 《Journal of molecular recognition : JMR》2015,28(11):667-678
A surface acoustic wave sensor operating at 104 MHz and functionalized with a polypyrrole molecularly imprinted polymer has been designed for selective detection of dopamine (DA). Optimization of pyrrole/DA ratio, polymerization and immersion times permitted to obtain a highly selective sensor, which has a sensitivity of 0.55°/mM (≈550 Hz/mM) and a detection limit of ≈ 10 nM. Morphology and related roughness parameters of molecularly imprinted polymer surfaces, before and after extraction of DA, as well as that of the non imprinted polymer were characterized by atomic force microscopy. The developed chemosensor selectively recognized dopamine over the structurally similar compound 4‐hydroxyphenethylamine (referred as tyramine), or ascorbic acid,which co‐exists with DA in body fluids at a much higher concentration. Selectivity tests were also carried out with dihydroxybenzene, for which an unexpected phase variation of order of 75% of the DA one was observed. Quantum chemical calculations, based on the density functional theory, were carried out to determine the nature of interactions between each analyte and the PPy matrix and the DA imprinted PPy polypyrrole sensing layer in order to account for the important phase variation observed during dihydroxybenzene injection. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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The orientation of the mitotic spindle plays a key role in determining whether a polarized cell will divide symmetrically or asymmetrically. In most cell types, cytoplasmic dynein plays a critical role in spindle orientation. However, how dynein directs opposite spindle poles toward distinct and predetermined cell ends is poorly understood. Here, we show that dynein distributes preferentially to the spindle pole bodies (SPB) and astral microtubules (MTs) proximal to the bud in metaphase yeast cells. Dynein asymmetry depended on the bud neck kinases Elm1, Hsl1, and Gin4, on the spindle pole components Cnm67 and Cdk1, and on the B-type cyclins Clb1 and Clb2. Furthermore, phenotypic and genetic studies both indicated that dynein is unable to orient the spindle when it localizes to both poles and associated microtubules. Together, our data indicate that proper orientation of the spindle requires dynein to act on a single spindle pole. 相似文献
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Thera MA Doumbo OK Coulibaly D Diallo DA Kone AK Guindo AB Traore K Dicko A Sagara I Sissoko MS Baby M Sissoko M Diarra I Niangaly A Dolo A Daou M Diawara SI Heppner DG Stewart VA Angov E Bergmann-Leitner ES Lanar DE Dutta S Soisson L Diggs CL Leach A Owusu A Dubois MC Cohen J Nixon JN Gregson A Takala SL Lyke KE Plowe CV 《PloS one》2008,3(1):e1465
Background
The objective was to evaluate the safety, reactogenicity and immunogenicity of the AMA-1-based blood-stage malaria vaccine FMP2.1/AS02A in adults exposed to seasonal malaria.Methodology/Principal Findings
A phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02A is a recombinant protein (FMP2.1) based on apical membrane antigen-1 (AMA-1) from the 3D7 clone of P. falciparum, adjuvanted with AS02A. The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert). Sixty healthy, malaria-experienced adults aged 18–55 y were recruited into 2 cohorts and randomized to receive either a half dose or full dose of the malaria vaccine (FMP2.1 25 µg/AS02A 0.25 mL or FMP2.1 50 µg/AS02A 0.5 mL) or rabies vaccine given in 3 doses at 0, 1 and 2 mo, and were followed for 1 y. Solicited symptoms were assessed for 7 d and unsolicited symptoms for 30 d after each vaccination. Serious adverse events were assessed throughout the study. Titers of anti-AMA-1 antibodies were measured by ELISA and P. falciparum growth inhibition assays were performed on sera collected at pre- and post-vaccination time points. Transient local pain and swelling were common and more frequent in both malaria vaccine dosage groups than in the comparator group. Anti-AMA-1 antibodies increased significantly in both malaria vaccine groups, peaking at nearly 5-fold and more than 6-fold higher than baseline in the half-dose and full-dose groups, respectively.Conclusion/Significance
The FMP2.1/AS02A vaccine had a good safety profile, was well-tolerated, and was highly immunogenic in malaria-exposed adults. This malaria vaccine is being evaluated in Phase 1 and 2 trials in children at this site.Trial Registration
ClinicalTrials.gov NCT00308061相似文献5.
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Safiatou Niaré-Doumbo Anne Cécile Normand Yacouba Lazarre Diallo Abdoul Karim Dembelé Mahamadou A. Thera Dapa Diallo Renaud Piarroux Ogobara Doumbo Stéphane Ranque 《Mycopathologia》2014,178(1-2):103-109
Data on fungal epidemiology in sub-Saharan African countries are scarce. This exploratory study aimed to characterize the fungal flora at the Onco-Haematology ward of the National Teaching Hospital of Point G in Bamako, Mali. A cross-sectional survey was conducted in the dry and in the rainy seasons. Nasal swab and sputum samples were collected from the hospitalized patients while airborne fungal spores were collected using electrostatic dust-fall collectors. Fungi were identified by their morphological characteristics and MALDI-TOF mass spectrometry. Candida albicans was the most frequent yeast species colonizing patients; Aspergillus species were isolated in 86 % of the patients and were the main airborne environmental contaminants. Overall, airborne fungal contamination rates increased from 33.8 % in the dry to 66.2 % in the rainy season (p < 0.001). The most frequent Aspergillus species were Aspergillus niger (36.6 %) and Aspergillus flavus (32.92 %). In contrast, Aspergillus fumigatus (5.43 %) was relatively rare. This high level of fungal exposure raises concern regarding the management of at-risk patients in this Onco-Haematology ward and stresses the need for strengthening the mycological diagnostic capacities to accompany the implementation of adapted fungal infection prevention and management policies. 相似文献
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Valentina D. Mangano Taane G. Clark Sarah Auburn Susana Campino Mahamadou Diakite Andrew E. Fry Angela Green Anna Richardson Muminatou Jallow Fatou Sisay-Joof Margaret Pinder Michael J. Griffiths Charles Newton Norbert Peshu Thomas N. Williams Kevin Marsh Malcolm E. Molyneux Terrie E. Taylor David Modiano Dominic P. Kwiatkowski Kirk A. Rockett 《PloS one》2009,4(1)
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Effects of the inoculation of cyanobacteria on the microstructure and the structural stability of a tropical soil 总被引:3,自引:0,他引:3
Oumarou Malam Issa Christian Défarge Yves Le Bissonnais Béatrice Marin Odile Duval Ary Bruand Luigi Paolo D’Acqui Sofie Nordenberg Marcus Annerman 《Plant and Soil》2007,290(1-2):209-219
Cyanobacteria are widespread photosynthetic microorganisms among which some are able to fix atmospheric nitrogen. We investigated
the impact of indigenous cyanobacteria strains (Nostoc) inoculation on physical characteristics of poorly aggregated soils from Guquka (Eastern Cape, South Africa). The soil aggregates
(3–5 mm) were arranged into a layer of 10–20 mm thick, and sprayed with cyanobacteria solution. Subsequently the inoculated
and un-inoculated samples were incubated (30°C, 80% humidity, continuous illumination at 100 μmol m−2 s−1). Their micromorphological characteristics and aggregate stability were investigated, after 1, 2, 3, 4 and 6 weeks of incubation,
by using high resolution Cryo-SEM and aggregate breakdown tests.
Micromorphological investigations revealed that the surface of un-inoculated samples remained uncovered, while the inoculated
samples were partially covered by cyanobacteria material after one week of incubation. A dense superficial network of cyanobacterial
filaments and extracellular polymer secretions (EPS) covered their surface after 4 and 6 weeks of incubation. Organo-mineral
aggregates comprising cyanobacterial filaments and EPS were observed after 6 weeks of incubation. The results of aggregate
breakdown tests showed no significant difference between un-inoculated samples after 1, 2, 3, 4 or 6 weeks, while they revealed
improvement of aggregate stability for inoculated samples. The improvement of aggregate stability appeared in a short while
following inoculation and increased gradually with time and cyanobacteria growth. The increase in aggregate stability is likely
related to the changes induced in micromorphological characteristics by cyanobacterial filaments and EPS. It reflects the
effect of coating, enmeshment, binding and gluing of aggregates and isolated mineral particles by cyanobacteria material.
Our study presents new data demonstrating the improvement of soil physical quality in a few weeks after cyanobacteria inoculation.
The interaction of the inocula and other biotic components is worthy of study before field application of cyanobacteria. 相似文献
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Polyparasitism with Schistosoma mansoni,geohelminths, and intestinal protozoa in rural Côte d'Ivoire
Keiser J N'Goran EK Traoré M Lohourignon KL Singer BH Lengeler C Tanner M Utzinger J 《The Journal of parasitology》2002,88(3):461-466
Single species infections with schistosomes, geohelminths, and intestinal protozoans are common over large parts of sub-Saharan Africa, and it is expected that polyparasitism affects a considerable proportion of the population, hence posing a great toll on public health. However, few investigations have been carried out to quantify the extent of polyparasitism. Here, a detailed assessment is reported for the epidemiology of Schistosoma mansoni, geohelminths, and intestinal protozoan infections, with particular emphasis on polyparasitism among 260 community members in rural C?te d'Ivoire. Schistosoma mansoni, Entamoeba coli, and hookworm were the predominant species with prevalences of 71.5, 64.6, and 51.9%, respectively. Only 8 individuals displayed no infection, whereas two-thirds of the population harbored 3 or more parasites concurrently. There were a series of significant pairwise parasite co-occurrences, e.g., between S. mansoni and hookworms and between S. mansoni and E. coli. It is concluded that polyparasitism in the population studied here was very common, which is probably the case also in other areas of rural C?te d'Ivoire and elsewhere in sub-Saharan Africa. These findings call for integrated approaches to effectively control multiple parasitic and protozoan infections. 相似文献