Mechanistic Plug-And-Play Models for Understanding the Impact of Control and Climate on Seasonal Dengue Dynamics in Iquitos, Peru

Dengue virus is a mosquito-borne multi-serotype disease whose dynamics are not precisely understood despite half of the world’s human population being at risk of infection. A recent dataset of dengue case reports from an isolated Amazonian city— Iquitos, Peru—provides a unique opportunity to assess dengue dynamics in a simpli- fied setting. Ten years of clinical surveillance data reveal a specific pattern: two novel serotypes, in turn, invaded and exclusively dominated incidence over several seasonal cycles, despite limited intra-annual variation in climate conditions. Together with mechanistic mathematical models, these data can provide an improved understand- ing of the nonlinear interactions between the environmental and biological factors underlying dengue transmission as well as aid in the prediction of future epidemics. To examine the drivers of dengue in Iquitos we develop several stochastic discrete- time models and use likelihood-based plug-and-play inference techniques to explore potential factors that may explain the seasonal transmission pattern. By including climate-informed variables and accounting for known vector control measures in our model, we illustrate scenarios that can replicate the observed data and uncover the contribution of previously overlooked factors, such as the role of disease importation from human population migration. We discuss the implications of these results for understanding dengue dynamics in other endemic settings

Resistance of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis to nitric oxide correlates with disease severity in Tegumentary Leishmaniasis

BACKGROUND: Nitric oxide (NO(•)) plays a pivotal role as a leishmanicidal agent in mouse macrophages. NO(• )resistant Escherichia coli and Mycobacterium tuberculosis have been associated with a severe outcome of these diseases. METHODS: In this study we evaluated the in vitro toxicity of nitric oxide for the promastigote stages of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis parasites, and the infectivity of the amastigote stage for human macrophages. Parasites were isolated from patients with cutaneous, mucosal or disseminated leishmaniasis, and NO(• )resistance was correlated with clinical presentation. RESULTS: Seventeen isolates of L. (L.) amazonensis or L. (V.) braziliensis promastigotes were killed by up to 8 mM of more of NaNO(2 )(pH 5.0) and therefore were defined as nitric oxide-susceptible. In contrast, eleven isolates that survived exposure to 16 mM NaNO(2 )were defined as nitric oxide-resistant. Patients infected with nitric oxide-resistant Leishmania had significantly larger lesions than patients infected with nitric oxide-susceptible isolates. Furthermore, nitric oxide-resistant L. (L.) amazonensis and L. (V.) braziliensis multiplied significantly better in human macrophages than nitric oxide-susceptible isolates. CONCLUSION: These data suggest that nitric oxide-resistance of Leishmania isolates confers a survival benefit for the parasites inside the macrophage, and possibly exacerbates the clinical course of human leishmaniasis

Patient- and Community-Level Sociodemographic Characteristics Associated with Emergency Department Visits for Childhood Injury

ObjectiveTo examine pediatric emergency department (ED) visits over 5 years, trends in injury severity, and associations between injury-related ED visit outcome and patient and community-level sociodemographic characteristics.Study designRetrospective analysis of administrative data provided to the Pediatric Emergency Care Applied Research Network Core Data Project, 2004-2008. Home addresses were geocoded to determine census block group and associated sociodemographic characteristics. Maximum Abbreviated Injury Scale severity and Severity Classification System scores were calculated. Generalized estimating equations were used to test for associations between sociodemographic characteristics and admission or transfer among injury-related ED visits.ResultsOverall ED visits and injury-related visits increased from 2004 to 2008 at study sites. Of 2,833676 successfully geocoded visits, 700,821 (24.7%) were injury-related. The proportion of higher severity injury-related visits remained consistent. Nearly 10% of injury-related visits resulted in admission or transfer each year. After adjusting for age, sex, payer, and injury severity, odds of admission or transfer were lower among minority children and children from areas with moderate and high prevalence of poverty.ConclusionsPediatric injury-related ED visits to included sites increased over the study period while injury severity, anticipated resource utilization, and visit outcomes remained stable, with low rates of admission or transfer. Sociodemographic differences in injury-related visits and ED disposition were apparent. ED-based injury surveillance is essential to understand disparities, inform targets for prevention programs, and reduce the overall burden of childhood injuries

Patient- and Community-Level Sociodemographic Characteristics Associated with Emergency Department Visits for Childhood Injury

ObjectiveTo examine pediatric emergency department (ED) visits over 5 years, trends in injury severity, and associations between injury-related ED visit outcome and patient and community-level sociodemographic characteristics.Study designRetrospective analysis of administrative data provided to the Pediatric Emergency Care Applied Research Network Core Data Project, 2004-2008. Home addresses were geocoded to determine census block group and associated sociodemographic characteristics. Maximum Abbreviated Injury Scale severity and Severity Classification System scores were calculated. Generalized estimating equations were used to test for associations between sociodemographic characteristics and admission or transfer among injury-related ED visits.ResultsOverall ED visits and injury-related visits increased from 2004 to 2008 at study sites. Of 2,833676 successfully geocoded visits, 700,821 (24.7%) were injury-related. The proportion of higher severity injury-related visits remained consistent. Nearly 10% of injury-related visits resulted in admission or transfer each year. After adjusting for age, sex, payer, and injury severity, odds of admission or transfer were lower among minority children and children from areas with moderate and high prevalence of poverty.ConclusionsPediatric injury-related ED visits to included sites increased over the study period while injury severity, anticipated resource utilization, and visit outcomes remained stable, with low rates of admission or transfer. Sociodemographic differences in injury-related visits and ED disposition were apparent. ED-based injury surveillance is essential to understand disparities, inform targets for prevention programs, and reduce the overall burden of childhood injuries

Properties and Immune Function of Cardiac Fibroblasts.

This chapter will discuss the role of cardiac fibroblasts as a target of various immunological inputs as well as an immunomodulatory hub of the heart through interaction with immune cell types and chemokine or cytokine signaling. While the purpose of this chapter is to explore the immunomodulatory properties of cardiac fibroblasts, it is important to note that cardiac fibroblasts are not a homogeneous cell type, but have a unique embryological origin and molecular identity. Specific properties of cardiac fibroblasts may influence the way they interact with the heart microenvironment to promote healthy homeostatic function or respond to pathological insults. Therefore, we will briefly discuss these aspects of cardiac fibroblast biology and then focus on their immunomodulatory role in the heart. Adv Exp Med Biol 2017; 1003:35-70