Background: Recently, combined photodynamic therapy (PDT) and photothermal therapy (PTT) has become a desired treatment for cancer. However, the development of economic, high-efficiency, and safe photosensitizers/photothermal agents remains a significant challenge. Methods: A novel nanocomposite has been developed via the assembly of iron oxide carbon dot (Fe₃O₄-CDs) nanoparticles and black phosphorus quantum dots (genipin [GP]-polyglutamic acid [PGA]-Fe₃O₄-CDs@BPQDs), and this nanocomposite shows a broad light-absorption band and a photodegradable character. Results: In vitro and in vivo assays indicated that GP-PGA-Fe₃O₄-CDs@BPQDs were highly biocompatible and exhibited excellent tumor-inhibition efficacy, due to the synergistic PTT and PDT via a near-infrared laser. Importantly, in vivo tumor magnetic resonance imaging (MRI) results illustrated that GP-PGA-Fe₃O₄-CDs@BPQDs can be specifically applied for enhanced T₂ MRI of tumors. This work presents the first combined application of a PDT and PTT effect deriving from BPQDs and MRI from Fe₃O₄-CDs, which may promote utilization of black BPQDs in biomedicine. Conclusion: As expected, GP-PGA-Fe₃O₄-CDs@BPQDs displayed a dramatically enhanced ability to destroy tumor cells, due to the synergistic combination of PTT and PDT.

The arboviral disease cycle requires that key tissues in the arthropod vector become persistently infected with the virus. The midgut is the first organ in the mosquito that needs to be productively infected with an orally acquired virus. Following midgut infection, the virus then disseminates to secondary tissues including the salivary glands. Once these are productively infected, the mosquito is able to transmit the virus to a vertebrate host. Recently, we described the midgut dissemination pattern for chikungunya virus in Aedes aegypti. Here we assess the dissemination pattern in the same mosquito species for Zika virus (ZIKV), a human pathogenic virus belonging to the Flaviviridae. ZIKV infection of secondary tissues, indicative of dissemination from the midgut, was not observed before 72 h post infectious bloodmeal (pibm). Virion accumulation at the midgut basal lamina (BL) was only sporadic, although at 96–120 h pibm, virions were frequently observed between strands of the BL indicative of their dissemination. Our data suggest that ZIKV dissemination from the mosquito midgut occurs after digestion of the bloodmeal. Using gold-nanoparticles of 5 nm and 50 nm size, we show that meal ingestion leads to severe midgut tissue distention, causing the mesh width of the BL to remain enlarged after complete digestion of the meal. This could explain how ZIKV can exit the midgut via the BL after bloodmeal digestion. Ingestion of a subsequent, non-infectious bloodmeal five days after acquisition of an initial, dengue 4 virus containing bloodmeal resulted in an increased number of virions present in the midgut epithelium adjacent to the BL. Thus, subsequent bloodmeal ingestion by an infected mosquito may primarily stimulate de novo synthesis of virions leading to increased viral titers in the vector.