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Therapeutic efficacy of a systemic drug delivery largely depends on the targeting design of the delivery system, which tackles with circulatory traffic and prevents the nonspecific distribution of the drug in the wide range of vital organs. A drawing attention has been given to a biomimetic cloaking of the synthetic drug delivery nanoparticle using mammalian cell-ghosts, which has shown the installment of the biological complexity of the original cells thereby acting as naïve cells, to precisely delivery drug to the intended target. Align towards this direction; we developed a membrane camouflage fusogenic liposomal delivery system “NKsome” for targeted tumor therapy using Natural Killer (NK) cell-ghost, which naturally undergoes immunosurveillance of diseased/stress cells. The engineered NKsome shows successful retention of NK cell membrane-associated targeting protein on its surface. With its excellent biocompatibility, NKsome shows a higher affinity towards cancer than normal cells as demonstrated by in vitro flow-passage assay, and exhibits enhanced tumor homing efficiency in-vivo with an extended plasma residence time of 18 h. Moreover, the therapeutic potential of doxorubicin-loaded NKsome shows promising antitumor activity in vivo against MCF-7 induced tumor model. Overall results illustrate the therapeutic advantages of NK cell biomimicry capable of communicating like immune cells for cooperative drug delivery. [ABSTRACT FROM AUTHOR]

Nanotechnology has gained significant penetration to different fields of medicine including drug delivery, disease interrogation, targeting and bio-imaging. In recent years, efforts have been put forth to assess the use of this technology in biodetoxification. In this review, we will discuss the current status of nanostructured biomaterials/nanoparticle (NP)-based technologies as a candidate biodetoxifying agent. Patient hospitalization due to illicit drug consumption, suicidal attempts and accidental toxin exposure are major challenges in the medical field. Overdoses of drugs/toxic chemicals or exposure to bacterial toxins or poisons are conventionally treated by voiding the stomach, administering activated charcoal or by using specific antidotes, if the toxin is known. Because of the limitations of these methods for safe and effective detoxification, advancements in nanotechnology may offer novel ways in intoxication support by using nanostructured biomaterials, such as liposomes, micellar nanocarriers, liquid crystalline nanoassemblies and ligand-based NPs. [ABSTRACT FROM AUTHOR]

In vitro cell-nanoparticle (NP) studies involve exposure of NPs onto the monolayer cells growing at the bottom of a culture plate, and assumed that the NPs evenly distributed for a dose-responsive effect. However, only a few proportion of the administered dose reaches the cells depending on their size, shape, surface, and density. Often the amount incubated (administered dose) is misled as a responsive dose. Herein, we proposed a cell adhesion-migration (CAM) strategy, where cells incubated with the NP coated cell culture substrate to maximize the cell-NP interaction and investigated the physiological properties of the cells. In the present study, cell adhesion and migration pattern of human breast cancer cell (MCF-7) and mouse melanoma cell (B16-F10) on cell culture substrate decorated with toxic (cetyltrimethylammonium bromide, CTAB) and biocompatible (poly (sodium 4-styrenesulphonate), PSS) gold nanoparticles (AuNPs) of different sizes (5 and 40 nm) were investigated and evaluated for cellular uptake efficiency, proliferation, and toxicity. Results showed enhanced cell adhesion, migration, and nanoparticle uptake only on biocompatible PSS coated AuNP, irrespective of its size. Whereas, cytotoxic NP shows retard proliferation with reduced cellular uptake efficiency. Considering the importance of cell adhesion and migration on cellular uptake and cytotoxicity assessment of nanoparticle, CAM strategy would hold great promises in cell-NP interaction studies. [ABSTRACT FROM AUTHOR]

In the present study, a biomimetic nanoconstruct (BNc) with a multimodal imaging system is engineered using tumor homing natural killer cell membrane (NKM), near‐infrared (NIR) fluorescent dye, and gadolinium (Gd) conjugate‐based magnetic resonance imaging contrast agent onto the surface of a polymeric nanoparticle. The engineered BNc is 110 ± 20 nm in size and showed successful retention of NKM proteins. The magnetic properties of the BNc are found to be tunable from 2.1 ± 0.17 to 5.3 ± 0.5 mm−1 s−1 under 14.1 T, by adjusting the concentration of Gd‐lipid conjugate onto the surface of the BNc. Confocal imaging and cell sorting analysis reveal a distinguishable cellular interaction of the BNc with MCF‐7 cells in comparison to that of bare polymeric nanoparticles suggesting the tumor homing properties of NKM camouflage system. The in vitro cellular interaction results are further confirmed by in vivo NIR fluorescent tumor imaging and ex vivo MR imaging, respectively. Pharmacokinetics and biodistribution analysis of the BNc show longer circulation half‐life (≈9.5 h) and higher tumor accumulation (10% of injected dose) in MCF‐7 induced tumor‐bearing immunodeficient NU/NU nude mice. Owing to the proven immunosurveillance potential of NK‐cell in the field of immunotherapy, the BNc engineered herein would hold promises in the design consideration of nanomedicine engineering. A biomimetic nanoconstruct with a multimodal imaging system is engineered using tumor homing natural killer cell membrane, near‐infrared fluorescent dye, and a gadolinium conjugate‐based magnetic resonance imaging contrast agent onto the surface of a polymeric nanoparticle. The engineered nanoconstruct shows an extended plasma half‐life and a differential targeting specificity toward cancer. [ABSTRACT FROM AUTHOR]

We engineered nanomedicine with the stealth corona made up of densely packed bone seeking ligand, alendronic acid. In a typical nanoconstruct, alendronic acid is conjugated with hydrophilic head moiety of phospholipid that has an ability to self-assemble with hydrophobic polymeric core through its hydrophobic long carbon-chain. Proposed nanomedicine has three distinct compartments namely; poly(l-lactic-co-glycolic acid) polymeric core acting as a drug reservoir and skeleton of the nanoconstruct, phospholipid monolayer covers the core acting as a diffusion barrier, and a densely packed alendronic acid corona acting as a stabilizer and targeting moiety. Thus engineered nanomedicine attain spherical entity with ~90 ± 6 nm having negative zeta potential, −37.7 ± 2 mV, and has an ability to load 7 ± 0.3 wt% of doxorubicin. In-vitro bone targeting efficiency of nanomedicine was studied using hydroxyapatite crystals as a bone model, and found significant accumulation of nanoparticle in the crystals. Moreover, cellular internalization studies with mouse osteosarcoma confirm the selectivity of nanomedicine when compared to its internalization in non-targeted mouse melanoma. This nanomedicine shows prolong stability in serum and deliver the drug into the cell exhibiting an IC50 of 3.7 μM. Given the strong interacting property of alendronic acid with bone, the proposed nanomedicine hold promises in delivering drug to bone microenvironment. [ABSTRACT FROM AUTHOR]

• pH-responsive cationic properties. • Fusogenic characteristics monitored by fluorescence resonance energy transfer. • Strategic selection of building blocks of liposome for efficient cellular interaction. • Design consideration for endosomal escape mediated drug delivery. Endosomal degradation of the nanoparticle is one of the major biological barriers associated with the drug delivery system. Nanoparticles are internalized in the cell via different endocytosis pathways, where they are first delivered to early endosomes which mature to the late endosome and to the lysosome. During this journey, NP encounters a harsh chemical environment resulting in the degradation of NP and its content. This process is collectively called as intracellular defenses against foreign materials. Therefore, to avoid this degradative fate, the endosomal escape technique has been explored following membrane fusion or membrane destabilization mechanisms. However, these methods are limited to the application due to non-specific membrane fusion. To overcome this limitation, we have designed pH-responsive liposome made up of 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol hydrochloride (DC-liposome) in which the cationic nitrogen of the ammonium moiety occupies only ∼2.5 % of the molecule. Such a small percentage of the cationic moiety is sufficient enough to exhibit pH-responsive properties while maintaining the biocompatibility of the DC-liposome. DC-liposome showed pH-dependent cationic properties due to the protonation of DC-moiety at acidic pH. The fluorescence-based experiment confirmed pH-dependent fusogenic properties of DC-liposome. Furthermore, the endosomal colocalization study revealed higher localization of DC-liposome in the early endosome compared to that of the late endosome, suggesting possible endosomal escape. Elevated cationic and fusogenic properties of DC-liposome at acidic pH can mediate membrane fusion with anionic endosomal membrane via electrostatic interaction, thereby causing endosomal escape. Moreover, doxorubicin-loaded DC-liposome showed higher cytotoxicity than that of free doxorubicin further supporting our clam of endosomal escape. These findings suggest the potential of DC-liposome to break the endosomal barriers to enhance the therapeutic efficacy thereby guiding us in design consideration in the field of stimuli-responsive delivery agents. [ABSTRACT FROM AUTHOR]

Background. There is a lack of information regarding health literacy (HL) in elderly people in Vietnam. Objective. The aim of this study was to evaluate the health literacy and the associated factors in elderly people in Vietnam. Methods. A cross-sectional study was conducted on a sample of 300 elderly people aged 55 years and above. Data were obtained from study participants using face-to-face interviews using designed questionnaires on sociodemographics, behaviors, and health literacy. Multiple linear regression models were performed to identify potential determinants of health literacy. Results. HL scores were 29.70 ± 8.20 for the general HL dimension, 32.00 ± 9.60 for the healthcare dimension, 21.97 ± 10.06 for the disease prevention dimension, and 35.15 ± 9.43 for the health promotion dimension. In the final model, age was negatively associated with HL (B − coefficient = − 0.09 , 95% confidence interval (95% CI) (-0.17 to -0.008), P = 0.030). Occupation (B = 4.77 , 95% CI (3.18 to 6.36), P < 0.001), taking care of children (B = 1.68 , 95% CI (0.21 to 3.15), P = 0.025), social activity (B = 4.61 , 95% CI (2.86 to 6.37), P < 0.001), doing exercises (B = 2.52 , 95% CI (1.07 to 3.96), P = 0.001), television watching (B = 2.10 , 95% CI (0.75 to 3.45), P = 0.002), using the Internet (B = 2.93 , 95% CI (1.29 to 4.57), P = 0.001), and social connection (B = 3.50 , 95% CI (1.23 to 5.78), P = 0.003) were positively associated with HL, respectively. Conclusion. Age, occupation, and a number of behaviors were significantly associated with HL in elder people. Health education campaigns should take into account the above factors as facilitating access to the Internet and providing opportunities for social networks for the elderly. [ABSTRACT FROM AUTHOR]