RESUMEN
Aedes aegypti is a major vector for arboviruses such as dengue, chikungunya and Zika viruses. During acquisition of a viremic bloodmeal, an arbovirus infects mosquito midgut cells before disseminating to secondary tissues, including the salivary glands. Once virus is released into the salivary ducts it can be transmitted to another vertebrate host. The midgut is surrounded by a basal lamina (BL) in the extracellular matrix, consisting of a proteinaceous mesh composed of collagen IV and laminin. BL pore size exclusion limit prevents virions from passing through. Thus, the BL probably requires remodelling via enzymatic activity to enable efficient virus dissemination. Matrix metalloproteinases (MMPs) are extracellular endopeptidases that are involved in remodelling of the extracellular matrix. Here, we describe and characterize the nine Ae. aegypti encoded MMPs, AeMMPs 1-9, which share common features with other invertebrate and vertebrate MMPs. Expression profiling in Ae. aegypti revealed that Aemmp4 and Aemmp6 were upregulated during metamorphosis, whereas expression of Aemmp1 and Aemmp2 increased during bloodmeal digestion. Aemmp1 expression was also upregulated in the presence of a bloodmeal containing chikungunya virus. Using polyclonal antibodies, AeMMP1 and AeMMP2 were specifically detected in tissues associated with the mosquito midgut.
Asunto(s)
Aedes/enzimología , Metaloproteinasas de la Matriz/metabolismo , Aedes/genética , Aedes/crecimiento & desarrollo , Aedes/virología , Secuencia de Aminoácidos , Animales , Virus Chikungunya/fisiología , Femenino , Tracto Gastrointestinal/enzimología , Expresión Génica , Genoma de los Insectos , Humanos , Masculino , Metaloproteinasas de la Matriz/genética , Metamorfosis Biológica , Datos de Secuencia Molecular , Homología de Secuencia de Ácido NucleicoRESUMEN
Dissection of the thoracic aorta is a life-threatening event requiring imaging studies to define the level of the tear and the intimal flap. The "gold standard" has been angiography. This method may fail to demonstrate the dissection, however, due to overlap of the true and false lumens or a very thin flap that is imaged en face rather than tangentially. Computed tomography has a diagnostic accuracy of 95%, but can fail to image the dissection due to technical factors or a thrombosed false lumen. Magnetic resonance imaging requires a hemodynamically stable and cooperative patient. A diagnostic algorithm is proposed for diagnosis of aortic dissection based on renal function and the surgeon's imaging modality preference.