The clearance of nanomedicine in inflamed joints has been accelerated due to the increased lymph angiogenesis and lymph flow in arthritic sites. To maximize the therapeutic efficacy for rheumatoid arthritis (RA), it is necessary to facilitate targeted delivery and extended drug retention in inflamed synovium simultaneously. In general, nanosized particles are more likely to achieve prolonged circulation and targeted delivery. While drug carriers with larger dimension might be more beneficial for extending drug retention. To balance the conflicting requirements, an inflammation-responsive shape transformable nanoparticle, comprised of amyloid β-derived KLVFF peptide and polysialic acid (PSA), coupled with therapeutic agent dexamethasone (Dex) via an acid-sensitive linker, was fabricated and termed as Dex-KLVFF-PSA (DKPNPs). Under physiological condition, DKPNPs can keep stable nanosized morphology, and PSA shell could endow DKPNPs with long circulation and active targeting to arthritic sites. While in inflamed joints, acidic pH-triggered Dex dissociation or macrophages-induced specific binding with PSA would induce the re-assembly of DKPNPs from nanoparticles to nanofibers. Our results reveal that intravenously injected DKPNPs display prolonged in vivo circulation and preferential distribution in inflamed joints, where DKPNPs undergo shape transition to fibrous structures, leading to declined lymphatic clearance and prolonged efficacy. Overall, our dual-stimulus responsive transformable nanoparticle offers an intelligent solution to achieve enhanced therapeutic efficacy in RA.

Maxillary defects occur either as a result of surgical resection of malignant tumors of the nasal cavity and paranasal sinuses or of the congenital causes. Rehabilitation of the patients with maxillectomy defects presents a challenge in restoring the lost form, function and speech. Maxillary interim obturators in prosthetic reconstruction of the defects are often complicated with lack of adequate retention, stability, and support. This case report presents the simplified approach, to rehabilitate a case of sub-total maxillectomy due to squamous cell carcinoma of maxillary sinus, using a closed hollow bulb obturator prosthesis fabricated with a \"U\" loop and a modified buccal flange for enhanced retention of the prosthesis.