Chapters authored
Current Status of the Insecticide Resistance in Aedes aegypti (Diptera: Culicidae) from Mexico
The mosquito Aedes aegypti (Diptera: Culicidae) is the primary vector of dengue in Mexico and lately virus Chikungunya, although Aedes albopictus is widely distributed; its role in both diseases’ transmission has not been confirmed. The control of mosquitoes in Mexico includes source reduction consisting in the elimination of containers that are favorable sites for oviposition and development of the aquatic stage. The use of insecticides is to control larvae and adulticides as outdoor ultra-low volume applications and indoor residual spray and more recently impregnated materials. The health department regulates the use of insecticides, and such regulations are revised and adapted over time. Since 1999, the vector control regulations gave preference to the use of pyrethroids, a permethrin-based formulation to control adult forms. This insecticide was used as the only adulticide in Mexico for more than 10 years. The consequences of this actions have evolved in a widespread and strong resistance to other insecticides, mainly pyrethroids. We include in this revision evidence of resistance reported in Ae. aegypti in Mexico.
Part of the book: Insecticides Resistance
Animal Models of Rheumatoid Arthritis
Autoimmunity is a condition in which the host organizes an immune response against its own antigens. Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology, characterized by the presence of chronic inflammatory infiltrates, the development of destructive arthropathy, bone erosion, and degradation of the articular cartilage and subchondral bone. There is currently no treatment that resolves the disease, only the use of palliatives, and not all patients respond to pharmacologic therapy. According to RA multifactorial origin, several in vivo models have been used to evaluate its pathophysiology as well as to identify the usefulness of biomarkers to predict, to diagnose, or to evaluate the prognosis of the disease. This chapter focuses on the most common in vivo models used for the study of RA, including those related with genetic, immunological, hormonal, and environmental interactions. Similarly, the potential of these models to understand RA pathogenesis and to test preventive and therapeutic strategies of autoimmune disorder is also highlighted. In conclusion, of all the animal models discussed, the CIA model could be considered the most successful by generating arthritis using type II collagen and adjuvants and evaluating therapeutic compounds both intra-articularly and systemically.
Part of the book: Experimental Animal Models of Human Diseases
Mosquito Excito-Repellency: Effects on Behavior and the Development of Insecticide Resistance
Mosquito’s resistance to avoiding insecticide-treated surfaces (“excito-repellency”) has two effects: irritation from direct contact with a treated area and repellency as an avoidance response to contact with treated surfaces. Nowadays, this behavior appears to reduce the success of mosquito control programs, particularly those based on insecticide-driven strategies. Different systems have been designed to assess the excito-repellency, evaluating numerous insecticides’ irritants, deterrents, and toxic properties at different concentrations. The information provides valuable insights regarding the patterns of mosquito behavior based on their physiological conditions, such as the age of the mosquitoes and the duration of the tests. However, the physiological processes resulting from chemical stimulus contact “chemoreception”) are still poorly explored and understood. This review provides an overview of insecticide effects on mosquito behavior and describes the mechanisms involved in chemical stimuli uptake, translation, and recognition.
Part of the book: Mosquito Research