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Find video protocols related to scientific articles indexed in Pubmed.
Discrepancies between Aedes aegypti identification in the field and in the laboratory after collection with a sticky trap.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 04-11-2014
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Currently, sticky traps are regularly employed to assist in the surveillance of Aedes aegypti infestation. We tested two alternative procedures for specimen identification performed by local health agents: directly in the field, as recommended by certain manufacturers, or after transportation to the laboratory. A total of 384 sticky traps (MosquiTRAP) were monitored monthly during one year in four geographically representative Brazilian municipalities. When the same samples were inspected in the field and in the laboratory, large differences were noted in the total number of mosquitoes recorded and in the number of specimens identified as Ae. aegypti by both procedures. Although field identification has the potential to speed vector surveillance, these results point to uncertainties in the evaluated protocol.
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Discrepancies between Aedes aegypti identification in the field and in the laboratory after collection with a sticky trap.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 04-11-2014
Show Abstract
Hide Abstract
Currently, sticky traps are regularly employed to assist in the surveillance of Aedes aegypti infestation. We tested two alternative procedures for specimen identification performed by local health agents: directly in the field, as recommended by certain manufacturers, or after transportation to the laboratory. A total of 384 sticky traps (MosquiTRAP) were monitored monthly during one year in four geographically representative Brazilian municipalities. When the same samples were inspected in the field and in the laboratory, large differences were noted in the total number of mosquitoes recorded and in the number of specimens identified as Ae. aegypti by both procedures. Although field identification has the potential to speed vector surveillance, these results point to uncertainties in the evaluated protocol.
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A Comparison of Sonographic Assessments and Clinical Questionnaire in the Diagnosis of HIV-Associated Lipodystrophy.
J Int Assoc Physicians AIDS Care (Chic)
PUBLISHED: 04-26-2011
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The study evaluated the use of sonographic measurements as an alternative to assessments based on clinical or other imaging techniques for the diagnosis of body-fat abnormalities. The study enrolled 179 HIV-infected patients, 81 (45.3%) of them diagnosed as lipodystrophy (LD)-positive based on a clinical standard questionnaire. Association between clinical LD and sonographic measurements of face, right upper limb, subcutaneous abdomen, and visceral compartments was evaluated by multiple logistic regression. The predicted probability of the logistic model was 0.64, corresponding to a maximum sensitivity of 69.1% (58%-79%), a specificity of 94.9% (88%-98%), and to positive and negative predictive values of 92% (82%-97%) and 79% (70%-86%), respectively. Kappa measure of concordance was 65% (54%-77%). Low sensitivity poses a problem for the use of sonography to detect LD in the clinical routine as a single exam, speaking in favor of the combined use of clinical and sonographic measurements over time.
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A Bayesian framework for parameter estimation in dynamical models.
PLoS ONE
PUBLISHED: 04-12-2011
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Mathematical models in biology are powerful tools for the study and exploration of complex dynamics. Nevertheless, bringing theoretical results to an agreement with experimental observations involves acknowledging a great deal of uncertainty intrinsic to our theoretical representation of a real system. Proper handling of such uncertainties is key to the successful usage of models to predict experimental or field observations. This problem has been addressed over the years by many tools for model calibration and parameter estimation. In this article we present a general framework for uncertainty analysis and parameter estimation that is designed to handle uncertainties associated with the modeling of dynamic biological systems while remaining agnostic as to the type of model used. We apply the framework to fit an SIR-like influenza transmission model to 7 years of incidence data in three European countries: Belgium, the Netherlands and Portugal.
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Relevance of differentiating between residential and non-residential premises for surveillance and control of Aedes aegypti in Rio de Janeiro, Brazil.
Acta Trop.
PUBLISHED: 01-05-2010
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Entomological surveys on Aedes aegypti (L.) often focus on residential premises, while ignoring non-residential premises. It has been proposed that the latter should be subject to specific monitoring strategies, since they have the potential to contribute a large proportion of the overall mosquito population. In this study, we used traps for ovipositing females to compare the levels of Ae. aegypti infestation in residential and non-residential premises and assess whether there was any evidence for a spatial association of infestation between non-residential premises and the surrounding homes. This information is important for designing specific surveillance programmes for these special sites and their surroundings. This study was conducted in three neighbourhoods of the city of Rio de Janeiro, Brazil, with distinct population densities, water services, dengue histories and vegetation coverage. Ae. aegypti abundance was measured using two types of traps (standard and sticky ovitraps) installed in five non-residential premises and 80 residential premises per neighbourhood. Mosquitoes were collected in the summer (January to March) and winter (June to September) of 2007. The distribution of captures per household per week did not differ significantly between the seasons, although larger numbers of eggs and adults were obtained during the summer. Most non-residential premises were not significantly more infested than homes, despite the larger quantities of containers. There were a few exceptions, including a transportation company, two recycling centres and a boat yard. These highly infested non-residential premises were also spatially associated with highly infested homes in the vicinity. Continuous monitoring with traps may be an effective way of evaluating non-residential premises as sources of dengue vectors for nearby communities.
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Spatial evaluation and modeling of Dengue seroprevalence and vector density in Rio de Janeiro, Brazil.
PLoS Negl Trop Dis
PUBLISHED: 03-20-2009
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Rio de Janeiro, Brazil, experienced a severe dengue fever epidemic in 2008. This was the worst epidemic ever, characterized by a sharp increase in case-fatality rate, mainly among younger individuals. A combination of factors, such as climate, mosquito abundance, buildup of the susceptible population, or viral evolution, could explain the severity of this epidemic. The main objective of this study is to model the spatial patterns of dengue seroprevalence in three neighborhoods with different socioeconomic profiles in Rio de Janeiro. As blood sampling coincided with the peak of dengue transmission, we were also able to identify recent dengue infections and visually relate them to Aedes aegypti spatial distribution abundance. We analyzed individual and spatial factors associated with seroprevalence using Generalized Additive Model (GAM).
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Seasonal dynamics of Aedes aegypti (Diptera: Culicidae) in the northernmost state of Brazil: a likely port-of-entry for dengue virus 4.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 01-07-2009
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Roraima is the northernmost state of Brazil, bordering both Venezuela and Guyana. Appropriate climate and vector conditions for dengue transmission together with its proximity to countries where all four dengue serotypes circulate make this state, particularly the capital Boa Vista, strategically important for dengue surveillance in Brazil. Nonetheless, few studies have addressed the population dynamics of Aedes aegypti in Boa Vista. In this study, we report temporal and spatial variations in Ae. aegypti population density using ovitraps in two highly populated neighbourhoods; Centro and Tancredo Neves. In three out of six surveys, Ae. aegypti was present in more than 80% of the sites visited. High presence levels of this mosquito suggest ubiquitous human exposure to the vector, at least during part of the year. The highest infestation rates occurred during the peak of the rainy seasons, but a large presence was also observed during the early dry season (although with more variation among years). Spatial distribution of positive houses changed from a sparse and local pattern to a very dense pattern during the dry-wet season transition. These results suggest that the risk of dengue transmission and the potential for the new serotype invasions are high for most of the year.
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The epidemic wave of influenza A (H1N1) in Brazil, 2009.
Cad Saude Publica
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This study describes the main features of pandemic influenza A (H1N1) in Brazil during 2009. Brazil is a large country that extends roughly from latitudes 5ºN to 34ºS. Brazil has tropical and sub-tropical climates, a heterogeneous population distribution, and intense urbanization in the southern portions of the country and along its Atlantic coast. Our analysis points to a wide variation in infection rates throughout the country, and includes both latitudinal effects and strong variations in detection rates. Two states (out of a total of 23) were responsible for 73% of all cases reported. Real time reproduction numbers demonstrate that influenza transmission was sustained in the country, beginning in May of 2009. Finally, this study discusses the challenges in understanding the infection dynamics of influenza and the adequacy of Brazils influenza monitoring system.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.