Erythrocyte-Membrane-Camouflaged Magnetic Nanocapsules With Photothermal/Magnetothermal Effects for Thrombolysis.

Venous/arterial thrombosis poses significant threats to human health. However, drug-enabled thrombolysis treatment often encounters challenges such as short half-life and low bioavailability. To address these issues, the design of erythrocyte-membrane (EM) camouflaged nanocapsules (USIO/UK@EM) incorporating ultra-small iron oxide (USIO) and urokinase (UK) drug, which exhibits remarkable photothermal/magnetothermal effects and drug delivery ability for venous/arterial thrombolysis, is reported. USIO, UK, and EM are coextruded to fabricate USIO/UK@EM with average sizes of 103.7 nm. As USIO/UK@EM possesses wide photoabsorption and good magnetic properties, its solution demonstrates a temperature increase to 41.8-42.9 °C within 5 min when exposed to an 808 nm laser (0.33 mW cm-2) or alternating magnetic field (AMF). Such photothermal/magnetothermal effect along with UK confers impressive thrombolytic rates of 82.4% and 74.2%, higher than that (≈15%) achieved by UK alone. Further, the EM coating extends the circulating half-life (t1/2 = 3.28 h). When USIO/UK@EM is administered to mice and rabbits, tail vein thrombus in mice and femoral artery thrombus in rabbits can be dissolved by the synergetic effect of thermothrombolysis and UK. Therefore, this study not only offers insights into the rational design of multifunctional biomimetic nanocapsules but also showcases a promising thrombolysis strategy utilizing nanomedicine.

Innovation in hepatic alveolar echinococcosis imaging: best use of old tools, and necessary evaluation of new ones.

Hepatic Alveolar Echinococcosis (HAE), caused by larvae of Echinococcus multilocularis, is a rare but potentially lethal parasitic disease. The first diagnostic suspicion is usually based on hepatic ultrasound exam performed because of abdominal symptoms or in the context of a general checkup; HAE diagnosis may thus also be an incidental finding on imaging. The next step should be Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). They play an important role in the initial assessment of the disease; with chest and brain imaging, they are necessary to assess the PNM stage (parasite lesion, neighboring organ invasion, metastases) of a patient with AE. Performed at least yearly, they also represent key exams for long-term follow-up after therapeutic interventions. Familiarity of radiologists with HAE imaging findings, especially in the endemic regions, will enable earlier diagnosis and more effective treatment. Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) is currently considered to be the only noninvasive, albeit indirect, tool for the detection of metabolic activity in AE. Delayed acquisition of images (3 hrs after FDG injection) enhances its sensitivity for the assessment of lesion metabolism and its reliability for the continuation/withdrawal of anti-parasite treatment. However, sophisticated equipment and high cost widely limit PET/CT use for routine evaluation. Preliminary studies show that new techniques, such as contrast-enhanced ultrasound (US), Dual Energy CT or Spectral CT, and Diffusion-Weighted MRI, might also be useful in detecting the blood supply and metabolism of lesions. However, they cannot be recommended before further evaluation of their reliability in a larger number of patients with a variety of locations and stages of AE lesions.

Assessment of early hepatic echinococcus multilocularis infection in rats with real-time contrast-enhanced ultrasonography.

The aim of this study was to demonstrate characteristic imaging and accurate evaluation of blood perfusion in early stage of hepatic alveolar echinococcosis (HAE) by contrast-enhanced ultrasonography (CEUS). The early stage of experimentally induced secondary HAE in 45 rats was studied. Thirty-six HAE lesions in 33 rats, confirmed by pathologic examination, were examined by ultrasound (US), color Doppler flow imaging (CDFI) and then CEUS. Thirty-three lesions were found in 30 rats by US, and 30 lesions were detected in 27 rats by CEUS. The sensitivity of US and CEUS was 92% (95% CI 76%-98%) and 82% (95% CI 65%-93%), respectively. US imaging characteristics were categorized into four types: hyperechoic spot (type 1, 45.5%, 15/33), granular hyperechoic spots (type 2, 12.1%, 4/33), hyperechoic lesion (type 3, 30.3%, 10/33) and mixed pattern (type 4, 12.1%, 4/33). CDFI failed to detect blood flow signals in any lesions. CEUS results for 30 lesions showed ring enhancement in the peripheral area during the arterial phase and no filling effect in either the portal or the delayed phase (46.7%, 14/30); ring enhancement combined with central septa enhancement during the arterial phase and portal venous phase (46.7, 14/30), and no enhancement (6.6%, 2/30). The enhanced area, confirmed by pathologic examination, was an inflammatory reaction belt surrounding the lesion. The results of this study suggest that US, with high sensitivity, can be used as a screening method for early HAE lesions in the animal model, while CEUS can be used for displaying the peripheral blood perfusion and vesicle structure.