BackgroundEbola virus disease (EVD) is a highly lethal condition for which no specific treatment has proven efficacy. In September 2014, while the Ebola outbreak was at its peak, the World Health Organization released a short list of drugs suitable for EVD research. Favipiravir, an antiviral developed for the treatment of severe influenza, was one of these. In late 2014, the conditions for starting a randomized Ebola trial were not fulfilled for two reasons. One was the perception that, given the high number of patients presenting simultaneously and the very high mortality rate of the disease, it was ethically unacceptable to allocate patients from within the same family or village to receive or not receive an experimental drug, using a randomization process impossible to understand by very sick patients. The other was that, in the context of rumors and distrust of Ebola treatment centers, using a randomized design at the outset might lead even more patients to refuse to seek care.Therefore, we chose to conduct a multicenter non-randomized trial, in which all patients would receive favipiravir along with standardized care. The objectives of the trial were to test the feasibility and acceptability of an emergency trial in the context of a large Ebola outbreak, and to collect data on the safety and effectiveness of favipiravir in reducing mortality and viral load in patients with EVD. The trial was not aimed at directly informing future guidelines on Ebola treatment but at quickly gathering standardized preliminary data to optimize the design of future studies.Methods and FindingsInclusion criteria were positive Ebola virus reverse transcription PCR (RT-PCR) test, age ≥ 1 y, weight ≥ 10 kg, ability to take oral drugs, and informed consent. All participants received oral favipiravir (day 0: 6,000 mg; day 1 to day 9: 2,400 mg/d). Semi-quantitative Ebola virus RT-PCR (results expressed in “cycle threshold” [Ct]) and biochemistry tests were performed at day 0, day 2, day 4, end of symptoms, day 14, and day 30. Frozen samples were shipped to a reference biosafety level 4 laboratory for RNA viral load measurement using a quantitative reference technique (genome copies/milliliter). Outcomes were mortality, viral load evolution, and adverse events. The analysis was stratified by age and Ct value. A “target value” of mortality was defined a priori for each stratum, to guide the interpretation of interim and final analysis.Between 17 December 2014 and 8 April 2015, 126 patients were included, of whom 111 were analyzed (adults and adolescents, ≥13 y, n = 99; young children, ≤6 y, n = 12). Here we present the results obtained in the 99 adults and adolescents. Of these, 55 had a baseline Ct value ≥ 20 (Group A Ct ≥ 20), and 44 had a baseline Ct value < 20 (Group A Ct < 20). Ct values and RNA viral loads were well correlated, with Ct = 20 corresponding to RNA viral load = 7.7 log10 genome copies/ml. Mortality was 20% (95% CI 11.6%–32.4%) in Group A Ct ≥ 20 and 91% (95% CI 78.8%–91.1%) in Group A Ct < 20. Both mortality 95% CIs i...
Ageing is the largest risk factor for age-related macular degeneration (AMD), and soft drusen and basal linear deposits are lipid-rich extracellular lesions specific to AMD. Oil red O binding neutral lipid represents a major age-related deposition in the Bruch membrane (BrM) and the first identified druse component. Decades after these seminal observations, a natural history of neutral lipid deposition has been articulated and a biochemical model proposed. Results obtained with multiple biochemical, histochemical, and ultrastructural methods, and supported indirectly by epidemiology, suggest that the RPE secretes apolipoprotein B (apoB)-lipoprotein particles of unusual composition into BrM, where they accumulate with age eventually forming a lipid wall, a precursor of basal linear deposit. The authors propose that constituents of these lesions interact with reactive oxygen species to form pro-inflammatory peroxidised lipids that elicit neovascularisation. Here, the authors summarise key evidence supporting both accumulation of BrM lipoproteins leading to lesion formation and lipoprotein production by the RPE. The authors update their model with genetic associations between AMD and genes historically associated with plasma HDL metabolism, and suggest future directions for research and therapeutic strategies based on an oil-spill analogy.
The largest risk factor for age-related macular degeneration (ARMD) is advanced age. A prominent age-related change in the human retina is the accumulation of histochemically detectable neutral lipid in normal Bruch’s membrane (BrM) throughout adulthood. This change has the potential to have a major impact on physiology of the retinal pigment epithelium (RPE). It occurs in the same compartment as drusen and basal linear deposit, the pathognomonic extracellular, lipid-containing lesions of ARMD. Here we present evidence from light microscopic histochemistry, ultrastructure, lipid profiling of tissues and isolated lipoproteins, and gene expression analysis that this deposition can be accounted for by esterified cholesterol-rich, apolipoprotein B-containing lipoprotein particles constitutively produced by the RPE. This work collectively allows ARMD lesion formation and its aftermath to be conceptualized as a response to the retention of a sub-endothelial apolipoprotein B lipoprotein, similar to a widely accepted model of atherosclerotic coronary artery disease (CAD) (Tabas et al., 2007). This approach provides a wide knowledge base and sophisticated clinical armamentarium that can be readily exploited for the development of new model systems and the future benefit of ARMD patients.
We demonstrate histologically sub-retinal drusenoid debris in three aged human eyes, two of them affected by age-related maculopathy. By postmortem fundus examination, the lesions appeared drusen-like, i.e., they were pale spots apparently at the level of the retinal pigment epithelium (RPE). Light and electron microscopy revealed aggregations of membranous debris, the principal constituent of soft drusen, in the sub-retinal space. Immunohistochemistry and confocal microscopy confirmed the presence of molecules typically associated with drusen (positive for unesterified cholesterol, apoE, complement factor H, and vitronectin) without evidence for molecules associated with photoreceptors (lectins and opsins), Müller cells (glial fibrillary acid protein and cellular retinal binding protein, CRALPB), or RPE (CRALPB). The fact that a drusenoid material, sharing some markers with conventional drusen, can occur on opposite faces of the RPE, suggests deranged polarity of normally highly vectorial processes for basolateral secretion from RPE, and that overproduction of secreted materials and direction of secretion are independently specified processes. In the future, drusenoid sub-retinal debris might be more frequently revealed by emerging high-resolution imaging techniques.
Purpose Lipofuscin contained in the retinal pigment epithelium (RPE) is the main source of fundus auto-fluorescence (FAF), the target of an imaging method useful for estimating the progression of geographic atrophy (GA) in clinical trials. To establish a cellular basis for hyperfluorescent GA border zones, histologic autofluorescence (HAF) was measured at defined stages of RPE pathologic progression. Design Experimental study. Participants and Controls Ten GA donor eyes (mean age ± standard deviation, 87.1±4.0 years) and 3 age-matched control eyes (mean age ± standard deviation, 84.0±7.2 years) without GA. Methods Ten–micrometer-thick sections were divided into zones of RPE morphologic features according to an 8-point scale. Any HAF excited by 488 nm light was imaged by laser confocal microscopy. The HAF intensity summed along vertical lines perpendicular to Bruch’s membrane at 0.2-μm intervals served as a surrogate for FAF. Intensity profiles in 151 zones were normalized to grade 0 at a standard reference location in each eye. Cross-sectional area, mean, and sum autofluorescence for individual RPE cells were measured (cellular autofluorescence [CAF]). Main Outcome Measures Statistically significant differences in intensity and localization of HAF and CAF at defined stages of RPE morphologic progression for GA and control eyes. Results The RPE morphologic features were most abnormal (cell rounding, sloughing, and layering; grade 2) and HAF intensity profiles were highest and most variable immediately adjacent to atrophic areas. Peaks in HAF intensity frequently were associated with vertically superimposed cells. The HAF value that optimally separated reactive RPE was 0.66 standard deviations more than the mean for uninvolved RPE and was associated with a sensitivity of 75.8% and a specificity of 76.3%. When variable cell area was accounted for, neither mean nor sum CAF differed significantly among the RPE pathologic grades. Conclusions Areas with advanced RPE alterations are most likely to exhibit clinically recognizable patterns of elevated FAF around GA, but may not predict cells about to die, because of vertically superimposed cells and cellular fragments. These data do not support a role for lipofuscin-related cell death and call into question the rationale of treatments targeting lipofuscin.
Mosquitoes and other arthropods may transmit medically important pathogens, in particular viruses such as West Nile virus. The presence of suitable hosts and competent vectors for those zoonotic viruses is essential for an enzootic transmission, which is a prerequisite for epidemics. To establish reliable risk projections, it is an urgent need for an exact identification of mosquito species, which is especially challenging in the case of sibling species, such as Culex. pipiens pipiens biotypes pipiens and molestus. To facilitate detection of different Culex pipiens forms and their hybrids we established a multiplex real-time PCR. Culex pipiens samples were obtained by egg raft collection and rearing until imago stage or adult sampling using CO2 baited traps and gravid traps. In total, we tested more than 16,500 samples collected all over Germany in the years 2011 and 2012. The predominant species in Germany are Culex pipiens pipiens biotype pipiens and Culex. torrentium, but we also detected Culex pipiens pipiens biotype molestus and hybrids of the two pipiens biotypes at sites where both species occur sympatrically. This report of a potentially important bridge vector for West Nile virus might have major impact in the risk projections for West Nile virus in Germany.
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