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Monteiro, R. A.

Publications and source records attributed to Monteiro, R. A..

2 recordsLinked to original sources

Dual-Functional Biomimetic Nanoclusters for Sustained Antifibrotic Therapy and Vascular Protection in Fibrosis Management

Fibrosis represents a critical pathological hallmark underlying multiple chronic diseases, yet conventional pharmacological interventions are hampered by limited bioavailability, rapid systemic clearance, and insufficient vascular protection. In this study, we developed a biomimetic nanocluster system designed to overcome these therapeutic bottlenecks. The nanoclusters were fabricated via a self-assembly approach using PLGA-PEG and cholesterol matrices to co-encapsulate pirfenidone (antifibrotic) and resveratrol (vascular protective agent). Physicochemical characterization confirmed uniform particle morphology, stable size distribution, and sustained colloidal stability. Pharmacokinetic evaluation revealed that nanoclusters achieved a delayed peak time and prolonged plateau phase, maintaining therapeutic drug concentrations in serum and hepatic tissue for up to 72 h, in contrast to the rapid clearance observed in micelle and free-drug formulations. Mechanistic investigations suggested that biomimetic surface engineering and electrostatic coupling contributed to suppressed burst release, enhanced retention in fibrotic microenvironments, and receptor-mediated uptake. Functional assays further demonstrated significant inhibition of hepatic stellate cell activation, reduction of collagen deposition, and improved endothelial tube formation. In a CCl{square}-induced hepatic fibrosis mouse model, nanocluster treatment markedly decreased fibrotic area and enhanced CD31-positive vessel density without detectable systemic toxicity. The finding highlight the dual antifibrotic and vascular protective effects of biomimetic nanoclusters, which substantially outperform conventional nanocarriers in both therapeutic durability and safety. The present work not only introduces a long-acting drug delivery paradigm for fibrotic disease management but also provides an engineering framework adaptable to broader applications in translational nanomedicine.

cancer biology↗

Modulation of defence and iron homeostasis genes in rice roots by the diazotrophic endophyte Herbaspirillum seropedicae

Rice is staple food of nearly half the worlds population. Rice yields must therefore increase to feed ever larger populations. By colonising rice and other plants, Herbaspirillum spp. stimulate plant growth and productivity. However the molecular factors involved are largely unknown. To further explore this interaction, the transcription profiles of Nipponbare rice roots inoculated with Herbaspirillum seropedicae were determined by RNA-seq. Mapping the 104 million reads against the Oryza sativa cv. Nipponbare genome produced 65 million unique mapped reads that represented 13,840 transcripts each with at least two-times coverage. About 7.4 % (1,019) genes were differentially regulated and of these 256 changed expression levels more than two times. Several of the modulated genes encoded proteins related to plant defence (e.g. a putative probenazole inducible protein), plant disease resistance as well as enzymes involved in flavonoid and isoprenoid synthesis. Genes related to the synthesis and efflux of phytosiderophores (PS) and transport of PS-iron complexes were also induced by the bacteria. These data suggest that the bacterium represses the rice defence system while concomitantly activating iron uptake. Transcripts of H. seropedicae were also detected amongst which genes involved in nitrogen fixation, cell motility and cell wall synthesis were the most expressed.\n\nHighlightsRNASeq of H. seropedicae colonised rice roots showed remarkable regulation of defence, metal transport, stress and signalling genes. Fe-uptake genes were highly induced with implications in plant nutrition and immunity.

plant biology↗