ABSTRACT
Un modelo matemático determinístico del tipo SIR para tres hospedadores es aplicado para analizar el proceso de transmisión de la leishmaniasis tegumentar americana, en las localidades Río Blanco y paraje Las Carmelitas, ubicadas en el Nordeste de la Provincia de Salta, Argentina, del mismo se deriva la expresión para el número de reproducibilidad basal Ro. Se implementa el modelo en ambiente MATLAB, en base a datos de las zonas endémicas se realizan simulaciones y se obtienen estimaciones numéricas de Ro. Para el caso de Río Blanco hemos obtenido el valor Ro = 4,689, mientras que para el paraje Las Carmelitas se obtuvo Ro = 1,948. Estudiando numéricamente el modelo también se estima la fuerza de infección, obteniendo para las localidades mencionadas 0,239 y 0,171 (unidad 1/año), respectivamente. Las simulaciones muestran que en la localidad de Río Blanco la fase endémica resulta más sostenida que la fase inter-epidémica presentada en el paraje Las Carmelitas. Las estimaciones obtenidas para estos parámetros epidemiológicos indican donde las instituciones del Ministerio de Salud Pública de la Provincia y de la Nación tendrán más dificultad para el control y la erradicación de la enfermedad.
A SIR-type deterministic mathematical model for three hosts is applied to analyze the transmission process for American tegumentary leishmaniasis in Río Blanco and Las Carmelitas, located in northeastern Salta Province, Argentina, and to derive the expression for the baseline reproducibility number Ro. The model is implemented in the MATLAB environment, and based on data from endemic areas, simulations are performed and numerical estimations of Ro are obtained. Río Blanco shows Ro = 4.689 and Las Carmelitas Ro = 1.948. By studying the model numerically, we also estimate the force of infection, namely 0.239 and 0.171 (unit 1/year), respectively. The simulations show that in Río Blanco, the endemic phase was more sustained than the inter-epidemic phase in Las Carmelitas. The estimations of these epidemiological parameters indicate where the Ministry of Health and Provincial Health Department will experience greater difficulty in controlling and eradicating the disease.
Subject(s)
Humans , Animals , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/transmission , Argentina/epidemiology , Epidemiologic Methods , PrevalenceABSTRACT
PURPOSE: To evaluate the roles of macrophages and their influences on the signal transduction in the periprosthetic osteolysis, the pro-inflammatory signals were analyzed in particles-stimulated macrophages. MATERIALS AND METHODS: Raw 264.7 cell line derived from mice macrophages was used as pre-osteoclasts. To increase the stimulatory effects, the particles were composed of PMMA and polyethylene. Under the similar conditions as osteoclast differentiation, we examined the effect of particles on the pro-inflammatory signals in macrophage: the production of TNF-alpha, the activity of MAPKs (mitogen-activated phosphorylation kinase), the expression of I-kappaB (Inhibitory (B) and the production of H2O2 and nitric oxide. RESULTS: The particles stimulated the secretion of TNF-alpha and increased the phosphorylation of p38 and ERK in course of time. The concentration of H2O2 was increased; however the nitric oxide formation was not increased by particle treatment. In addition, the production of H2O2 was synergistically increased by suboptimal stimulation with PMA (phorbol 12-myristate 13-acetate). Expressions of I-kappaB were inhibited by particles. CONCLUSION: The particles may stimulate the activation of MAPKs, the production of TNF-alpha, reactive oxygen species (ROS) and the activation of NF-kappaB in the pre-osteoclasts. We speculate that particles may mediate the pro-inflammatory signal cascade by the activation of NF-kappaB through ROS in pre-osteoclasts, rather than reactive nitrogen species (RNS). Therefore we suggest that the macrophages in inflammatory osteolysis may have the characteristics of pre-osteoclast as well as pro-inflammatory cell. Further researches should be recommended.
Subject(s)
Animals , Mice , Cell Line , Macrophages , NF-kappa B , Nitric Oxide , Osteoclasts , Osteolysis , Phosphorylation , Polyethylene , Polymethyl Methacrylate , Reactive Nitrogen Species , Reactive Oxygen Species , Signal Transduction , Tumor Necrosis Factor-alphaABSTRACT
No abstract available.