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11.
Alphonse Ouédraogo Alfred B. Tiono Désiré Kargougou Jean Baptiste Yaro Esperance Ouédraogo Youssouf Kaboré David Kangoye Edith C. Bougouma Adama Gansane Noelie Henri Amidou Diarra Souleymane Sanon Issiaka Soulama Amadou T. Konate Nora L. Watson Valerie Brown Jenny Hendriks Maria Grazia Pau Isabella Versteege Edison Wiesken Jerald Sadoff Issa Nebie Sodiomon B. Sirima 《PloS one》2013,8(11)
Background
Ad35.CS.01 is a pre-erythrocytic malaria candidate vaccine. It is a codon optimized nucleotide sequence representing the P. falciparum circumsporozoite (CS) surface antigen inserted in a replication deficient Adenovirus 35 backbone. A Phase 1a trial has been conducted in the USA in naïve adults and showed that the vaccine was safe. The aim of this study is to assess the safety and immunogenicity of ascending dosages in sub Saharan Africa.Methods
A double blind, randomized, controlled, dose escalation, phase Ib trial was conducted in a rural area of Balonghin, the Saponé health district (Burkina Faso). Forty-eight healthy adults aged 18-45 years were randomized into 4 cohorts of 12 to receive three vaccine doses (day 0, 28 and 84) of 109, 1010, 5X1010, 1011 vp of Ad35.CS.01 or normal saline by intra muscular injection. Subjects were monitored carefully during the 14 days following each vaccination for non serious adverse events. Severe and serious adverse events were collected throughout the participant study duration (12 months from the first vaccination). Humoral and cellular immune responses were measured on study days 0, 28, 56, 84, 112 and 140.Results
Of the forty-eight subjects enrolled, forty-four (91.7%) received all three scheduled vaccine doses. Local reactions, all of mild severity, occurred in thirteen (27.1%) subjects. Severe (grade 3) laboratory abnormalities occurred in five (10.4%) subjects. One serious adverse event was reported and attributed to infection judged unrelated to vaccine. The vaccine induced both antibody titers and CD8 T cells producing IFNγ and TNFα with specificity to CS while eliciting modest neutralizing antibody responses against Ad35.Conclusion
Study vaccine Ad35.CS.01 at four different dose levels was well-tolerated and modestly immunogenic in this population. These results suggest that Ad35.CS.01 should be further investigated for preliminary efficacy in human challenge models and as part of heterologous prime-boost vaccination strategies.Trial Registration
ClinicalTrials.gov NCT01018459 http://clinicaltrials.gov/ct2/show/NCT01018459 相似文献12.
Jasper van der Slegt Lijckle van der Laan Eelco J. Veen Yvonne Hendriks Jannie Romme Jan Kluytmans 《PloS one》2013,8(8)
Background
Surgical site infections (SSI’s) are associated with severe morbidity, mortality and increased health care costs in vascular surgery.Objective
To implement a bundle of care in vascular surgery and measure the effects on the overall and deep-SSI’s rates.Design
Prospective, quasi-experimental, cohort study.Methods
A prospective surveillance for SSI’s after vascular surgery was performed in the Amphia hospital in Breda, from 2009 through 2011. A bundle developed by the Dutch hospital patient safety program (DHPSP) was introduced in 2009. The elements of the bundle were (1) perioperative normothermia, (2) hair removal before surgery, (3) the use of perioperative antibiotic prophylaxis and (4) discipline in the operating room. Bundle compliance was measured every 3 months in a random sample of surgical procedures and this was used for feedback.Results
Bundle compliance improved significantly from an average of 10% in 2009 to 60% in 2011. In total, 720 vascular procedures were performed during the study period and 75 (10.4%) SSI were observed. Deep SSI occurred in 25 (3.5%) patients. Patients with SSI’s (28,5±29.3 vs 10.8±11.3, p<0.001) and deep-SSI’s (48.3±39.4 vs 11.4±11.8, p<0.001) had a significantly longer length of hospital stay after surgery than patients without an infection. A significantly higher mortality was observed in patients who developed a deep SSI (Adjusted OR: 2.96, 95% confidence interval 1.32–6.63). Multivariate analysis showed a significant and independent decrease of the SSI-rate over time that paralleled the introduction of the bundle. The SSI-rate was 51% lower in 2011 compared to 2009.Conclusion
The implementation of the bundle was associated with improved compliance over time and a 51% reduction of the SSI-rate in vascular procedures. The bundle did not require expensive or potentially harmful interventions and is therefore an important tool to improve patient safety and reduce SSI’s in patients undergoing vascular surgery. 相似文献13.
Wouter Suykerbuyk Tjeerd J. Bouma Laura L. Govers Kris Giesen Dick J. de Jong Peter Herman Jan Hendriks Marieke M. van Katwijk 《Ecosystems》2016,19(2):296-310
Changes in the seascape often result in altered hydrodynamics that lead to coinciding changes in sediment dynamics. Little is known on how altered sediment dynamics affect long-term seagrass persistence. We studied the thresholds of sediment dynamics in relation to seagrass presence by comparing sediment characteristics and seagrass presence data of seven separate seagrass meadows. All meadows had a long-term (>20 years) presence. Within these meadows, we distinguish so-called “hotspots” (areas within a meadow where seagrass was found during all mapping campaigns) and “coldspots” (with infrequent seagrass presence). We monitored static sediment characteristics (median grain size, bulk density, silt content) and sediment dynamics (that is, bed level change and maximum sediment disturbance depth), bioturbation (that is, lugworm densities and induced fecal pit and mound relief), and seagrass cover. We statistically analyzed which sediment characteristic best explains seagrass cover. Densely vegetated hotspots were shown to have lower sediment dynamics than sparsely vegetated hotspots and coldspots, whereas static sediment characteristics were similar (grain size, bulk density). The vegetation cover was either low (2–15%) or high (>30%) and sediment dynamics showed a threshold for vegetation cover. From this correlative finding, we postulate a self-sustaining feedback of relatively dense seagrass via sediment stabilization and accordingly a runaway feedback once the seagrass cover becomes too sparse. The sensitivity for sediment dynamics shown in our study implies that future existence of seagrass meadows may be at risk as ongoing climate change might directly (increased environmental extremes) or indirectly (changing seascapes) negatively affect seagrass beds. 相似文献
14.
P. M. J. F. Huijbers J. L. M. Hendriks W. J. M. Gerver P. J. De Jong K. De Meer 《American journal of physical anthropology》1996,101(2):137-144
This study investigates the nutritional status of native children in the highlands of Nepal (1,700–3,000 m) and explores the relationship between child mortality and surviving children's nutritional status. A random sample of 145 households from 11 villages in the Koshi Hill Zone in east Nepal was surveyed, and the nutritional status of the 438 children <14 years of age living in these households was assessed by means of anthropometry. We found a severe growth retardation in the Nepalese children compared to lowland reference groups as well as to highland children from the Andes. Child mortality and altitude are not significantly different between higher (Brahman and Chetri) and lower (Baisya and Sudra) caste households. A lower caste status and higher altitude of the household is associated with a significantly better nutritional status in offspring. In multiple regression analyses, improved nutritional status in children is significantly associated with lower caste (P = 0.001), higher altitude (P = 0.009), and less crowding (P = 0.001) but not with sibling mortality (P = 0.11). We thus conclude that nutritional status of children in households in the highlands of Nepal is associated with the household's socioeconomic status and altitude but not with mortality among siblings. © 1996 Wiley-Liss, Inc. 相似文献
15.
Tunahan Çakır Margriet M. W. B. Hendriks Johan A. Westerhuis Age K. Smilde 《Metabolomics : Official journal of the Metabolomic Society》2009,5(3):318-329
Reverse engineering of high-throughput omics data to infer underlying biological networks is one of the challenges in systems
biology. However, applications in the field of metabolomics are rather limited. We have focused on a systematic analysis of
metabolic network inference from in silico metabolome data based on statistical similarity measures. Three different data
types based on biological/environmental variability around steady state were analyzed to compare the relative information
content of the data types for inferring the network. Comparing the inference power of different similarity scores indicated
the clear superiority of conditioning or pruning based scores as they have the ability to eliminate indirect interactions.
We also show that a mathematical measure based on the Fisher information matrix gives clues on the information quality of
different data types to better represent the underlying metabolic network topology. Results on several datasets of increasing
complexity consistently show that metabolic variations observed at steady state, the simplest experimental analysis, are already
informative to reveal the connectivity of the underlying metabolic network with a low false-positive rate when proper similarity-score
approaches are employed. For experimental situations this implies that a single organism under slightly varying conditions
may already generate more than enough information to rightly infer networks. Detailed examination of the strengths of interactions
of the underlying metabolic networks demonstrates that the edges that cannot be captured by similarity scores mainly belong
to metabolites connected with weak interaction strength. 相似文献
16.
There is an inconsistency in the ways that doctors make clinical decisions regarding the treatment of babies born extremely prematurely. Many experts now recommend that clinical decisions about the treatment of such babies be individualized and consider many different factors. Nevertheless, many policies and practices throughout Europe and North America still appear to base decisions on gestational age alone or on gestational age as the primary factor that determines whether doctors recommend or even offer life‐sustaining neonatal intensive care treatment. These policies are well intentioned. They aim to guide doctors and parents to make decisions that are best for the baby. That is an ethically appropriate goal. But in relying so heavily on gestational age, such policies may actually do the babies a disservice by denying some babies treatment that might be beneficial and lead to intact survival. In this paper, we argue that such policies are unjust to premature babies and ought to be abolished. In their place, we propose individualized treatment decisions for premature babies. This would treat premature babies as we treat all other patients, with clinical decisions based on an individualized estimation of likelihood that treatment would be beneficial. 相似文献
17.
L. Wu G.J. de Roest M.L. Hendriks A.C. van Rossum C.C. de Cock C.P. Allaart 《Netherlands heart journal》2016,24(1):66-72
Background
The contribution of right ventricular (RV) stimulation to cardiac resynchronisation therapy (CRT) remains controversial. RV stimulation might be associated with adverse haemodynamic effects, dependent on intrinsic right bundle branch conduction, presence of scar, RV function and other factors which may partly explain non-response to CRT. This study investigates to what degree RV stimulation modulates response to biventricular (BiV) stimulation in CRT candidates and which baseline factors, assessed by cardiac magnetic resonance imaging, determine this modulation.Methods and results
Forty-one patients (24 (59 %) males, 67 ± 10 years, QRS 153 ± 22 ms, 21 (51 %) ischaemic cardiomyopathy, left ventricular (LV) ejection fraction 25 ± 7 %), who successfully underwent temporary stimulation with pacing leads in the RV apex (RVapex) and left ventricular posterolateral (PL) wall were included. Stroke work, assessed by a conductance catheter, was used to assess acute haemodynamic response during baseline conditions and RVapex, PL (LV) and PL+RVapex (BiV) stimulation.Compared with baseline, stroke work improved similarly during LV and BiV stimulation (∆+ 51 ± 42 % and ∆+ 48 ± 47 %, both p < 0.001), but individual response showed substantial differences between LV and BiV stimulation. Multivariate analysis revealed that RV ejection fraction (β = 1.01, p = 0.02) was an independent predictor for stroke work response during LV stimulation, but not for BiV stimulation. Other parameters, including atrioventricular delay and scar presence and localisation, did not predict stroke work response in CRT.Conclusion
The haemodynamic effect of addition of RVapex stimulation to LV stimulation differs widely among patients receiving CRT. Poor RV function is associated with poor response to LV but not BiV stimulation.Electronic supplementary material
The online version of this article (doi:10.1007/s12471-015-0770-x) contains supplementary material, which is available to authorized users. 相似文献18.
N. Nayan A.S.M. Sonnenberg W.H. Hendriks J.W. Cone 《Journal of applied microbiology》2018,125(2):468-479
Aim
In this study, the biological variation for improvement of the nutritive value of wheat straw by 12 Ceriporiopsis subvermispora, 10 Pleurotus eryngii and 10 Lentinula edodes strains was assessed. Screening of the best performing strains within each species was made based on the in vitro degradability of fungal‐treated wheat straw.Methods and Results
Wheat straw was inoculated with each strain for 7 weeks of solid state fermentation. Weekly samples were evaluated for in vitro gas production (IVGP) in buffered rumen fluid for 72 h. Out of the 32 fungal strains studied, 17 strains showed a significantly higher (P < 0·05) IVGP compared to the control after 7 weeks (227·7 ml g?1 OM). The three best Ceriporiopsis subvermispora strains showed a mean IVGP of 297·0 ml g?1 OM, while the three best P. eryngii and L. edodes strains showed a mean IVGP of 257·8 and 291·5 ml g?1 OM, respectively.Conclusion
Ceriporiopsis subvermispora strains show an overall high potential to improve the ruminal degradability of wheat straw, followed by L. edodes and P. eryngii strains.Significance and Impact of the Study
Large variation exists within and among different fungal species in the valorization of wheat straw, which offers opportunities to improve the fungal genotype by breeding. 相似文献19.
This article comprises a literature analysis of 41 river rehabilitation projects to assess the short-term (5 years) ability
of indicator groups to demonstrate progress towards river rehabilitation goals. Positive indications were compared to land-use,
river size, rehabilitation intervention and time. A questionnaire was developed to investigate river manager’s interpretation
of rehabilitation success and to assess their level of adherence to recommendations in the literature with regard to rehabilitation
assessment on a conceptual level. A total of 54 responses were received from respondents based in Germany, The Netherlands
and the United Kingdom. The results indicate that macroinvertebrate indicators, while widely used in assessing river rehabilitation
efforts, exhibited a lower frequency of positive responses than most other indicator types in the short term. Conversely,
terrestrial floodplain indicators exhibited the most frequent level of positive response for all ecological type indicators
leading to recommendations for further investigations into their use for short-term monitoring. Assessment procedures recommended
in literature are largely followed, illustrating the advances that have been made with regard to assessment planning. Indicator
responses are influenced by scale factors, for example, land-use and river size, that are often not considered by rehabilitation
managers. While an emphasis is placed on ecological, hydrological and morphological indicators in monitoring schemes, the
socioeconomic perspective (emphasized in the literature as forming an integral part of the river system) is neglected. 相似文献
20.
Otter-Nilsson M Hendriks R Pecheur-Huet EI Hoekstra D Nilsson T 《The EMBO journal》1999,18(8):2074-2083
Much recent work has focussed on the role of membrane-bound components in fusion. We show here that p97 and NSF are sufficient to mediate rapid membrane fusion. Fractionation of cytosol revealed that p97 and its co-factor, p47, constitutes the major fusion activity. This was confirmed by depleting p97 from the cytosol, which resulted in an 80% decrease in fusion. Using purified protein, p97 or NSF was found to be sufficient to mediate rapid fusion in an ATP-dependent manner. A regulatory role was observed for their corresponding co-factors, p47 and alpha-SNAP. When present at a molar ratio half of that of the ATPase, both co-factors increased fusion activity significantly. Intriguingly, at this ratio the ATPase activity of the complex measured in solution was at its lowest, suggesting that the co-factor stabilizes the ATP state. The fusion event involved mixing of both leaflets of the opposing membranes and contents of liposomes. We conclude from these data that p97, NSF and perhaps other related ATPases catalyse rapid and complete fusion between lipid bilayers on opposing membranes. This highlights a new role for p97 and NSF and prompts a re-evaluation of current fusion models. 相似文献