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Aberrant expression of circular RNAs (circRNAs) is frequently linked to colorectal cancer (CRC). Here, we identified circZFR as a promising biomarker for CRC diagnosis and prognosis. CircZFR was upregulated in CRC tissues and serum exosomes and its level was linked to cancer incidence, advanced-stages, and metastasis. In both in vitro and in vivo settings, circZFR promoted the growth and spread while suppressing apoptosis of CRC. Exosomes with circZFR overexpression promoted the proliferation and migration of cocultured CRC cells. Mechanistically, epithelial splicing regulatory protein 1 (ESRP1) in CRC cells may enhance the production of circZFR. BCL2-associated transcription factor 1 (BCLAF1) bound to circZFR, which prevented its ubiquitinated degradation. Additionally, circZFR sponged miR-3127-5p to boost rhotekin 2 (RTKN2) expression. Our TCP1-CD-QDs nanocarrier was able to carry and deliver circZFR siRNA (si-circZFR) to the vasculature of CRC tissues and cells, which inhibited the growth of tumors in patient-derived xenograft (PDX) models. Taken together, our results show that circZFR is an oncogenic circRNA, which promotes the development and spread of CRC in a BCLAF1 and miR-3127-5p-dependent manner. CircZFR is a possible serum biopsy marker for the diagnosis and a desirable target for further treatment of CRC. [ABSTRACT FROM AUTHOR]

In polymer nanocomposites (PNCs), microstructure relationships encompass the intricate connections between nanofiller placement in the polymer matrix and resultant composite characteristics. The dispersion, size, shape and chemical interactions of nanofillers impact PNC performance, with thermo physical qualities varying based on composition. Establishing a universal composition-property relationship for PNCs is challenging due to their vast chemical diversity. This study proposes an innovative machine learning (ML) approach, the Intelligent Honey Bee-Fused Dynamic Random Forest (IHB-FDRF), to predict the composition-microstructure relationship of PNCs. Leveraging computational vision and image recognition, the IHB-FDRF predicts nanoparticles (NP) dispersion, validated through coarse-grained molecular dynamics simulations. The model forecasts NP arrangement in PNCs in latent space, translating to the radial distribution function (RDF) using the IHB-FDRF algorithm. The Mean Squared Error (MSE) in predictions, quantifying the average squared difference between predicted and actual values, is impressively low at 0.005 during the training phase, affirming the model's accuracy. The study's robustness is further confirmed by the overlap of latent values in both areas, signifying convergence between hidden characteristics and ensuring reliability across diverse contexts. In summary, this study gives significant findings on PNC microstructure relationships. [ABSTRACT FROM AUTHOR]

A variety of nanoparticles (NPs) (e.g., SiO 2 , TiO 2 , CeO 2 , Co 3 O 4 , etc.) and their functionalized counterparts have been intensively investigated for improving the electrochemical and mechanical durability of polymer-based proton-exchange membranes (PEMs) for use in low- and intermediate-temperature fuel cells. This study is to conduct a comprehensive review on the roles of functionalized NPs in the performance enhancement of PEMs including proton conductivity, gas crossover resistance, electrochemical and mechanical durability, etc. A brief historical review of PEM fuel cell (PEMFC) technology is made. Typical types of NPs and their functionalization techniques are retrospected and their roles in the performance improvement of PEMs are compared in detail. Consequently, the opportunities and challenges to develop high-performance functionalized NPs for use in PEMs and PEMFCs are prospected and justified. [ABSTRACT FROM AUTHOR]

Bone regeneration and repair are complex processes with the potential of added complications, like delayed repair, fracture non-union, and post-surgical infections. These conditions remain a challenge globally, pressurizing the economy and patients suffering from these conditions. Applications of nanotechnology (NBT) in the field of medicine have provided a medium for several approaches to support these global challenges. Tissue engineering is one such field that has been on the rise in the last three decades through the utilization of NBT for addressing the challenges related to bone regeneration. First, NBT enables the formation of scaffolds at the nanoscale needed for bone tissue engineering (BTE) using natural and synthetic polymers, as well as with minerals and metals. Then, it aids the development of the nano-formulation strategized to deliver antimicrobial drugs and/or growth factors through various ways to enhance bone repair through the scaffold. Third, NBT facilitates the use of specialized nanoparticles to image and track cellular events in vitro as well as in vivo. This review is an effort to bring together the current knowledge in the field of BTE and present the scope of ever-evolving NBT, a contribution towards precision medicine.

Bone regeneration and repair are complex processes with the potential of added complications, like delayed repair, fracture non-union, and post-surgical infections. These conditions remain a challenge globally, pressurizing the economy and patients suffering from these conditions. Applications of nanotechnology (NBT) in the field of medicine have provided a medium for several approaches to support these global challenges. Tissue engineering is one such field that has been on the rise in the last three decades through the utilization of NBT for addressing the challenges related to bone regeneration. First, NBT enables the formation of scaffolds at the nanoscale needed for bone tissue engineering (BTE) using natural and synthetic polymers, as well as with minerals and metals. Then, it aids the development of the nano-formulation strategized to deliver antimicrobial drugs and/or growth factors through various ways to enhance bone repair through the scaffold. Third, NBT facilitates the use of specialized nanoparticles to image and track cellular events in vitro as well as in vivo. This review is an effort to bring together the current knowledge in the field of BTE and present the scope of ever-evolving NBT, a contribution towards precision medicine. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs), as self-renewing multipotent stromal cells, have been considered promising agents for cancer treatment. A large number of studies have demonstrated the valuable properties of MSC-based treatment, such as low immunogenicity and intrinsic tumor-trophic migratory properties. To enhance the potency of MSCs for therapeutic purposes, equipping MSCs with targeted delivery functions using genetic engineering is highly beneficial. Genetically engineered MSCs can express tumor suppressor agents such as pro-apoptotic, anti-proliferative, anti-angiogenic factors and act as ideal delivery vehicles. MSCs can also be loaded with nanoparticle drugs for increased efficacy and externally moderated targeting. Moreover, exosomes secreted by MSCs have important physiological properties, so they can contribute to intercellular communication and transfer cargo into targeted tumor cells. The precise role of genetically modified MSCs in tumor environments is still up for debate, but the beginning of clinical trials has been confirmed by promising results from preclinical investigations of MSC-based gene therapy for a wide range of malignancies. This review highlights the advanced techniques of engineering/nano-engineering and MSC-derived exosomes in tumor-targeted therapy.

Perovskite CsPbI3 quantum dots (QDs) were synthesized as a hole-transporting layer (HTL) of a planar perovskite solar cell (PSC). By using the Octam solution during the ligand engineering, CsPbI3 QDs exhibits a denser grain and a larger grain size due to the short-chain ligands of Octam. In addition, CsPbI3 QDs with the Octam solution showed a smooth and uniform surface on MAPbI3 film, indicating the QDs improved the microstructure of the MAPbI3 perovskite film. As a result, the PSC with CsPbI3 QDs as an HTL has the optimal open-circuit voltage as 1.09 V, the short-circuit current as 20.5 mA/cm2, and the fill factor (FF) as 75.7%, and the power conversion efficiency (PCE) as 17.0%. Hence, it is inferred that introducing QDs as a HTL via the ligand engineering can effectively improve the device performance of the PSC. [ABSTRACT FROM AUTHOR]

In this study, blue perovskite quantum dots (PQDs) were prepared using didodecyldimethylammonium bromide (DDAB), which can passivate surface defects caused by the loss of surface ligands and reduce particle size distribution. After the passivation of DDAB, blue CsPbClxBr3−x PQDs dispersed in n-octane produced a more compact and uniform PQD thin film than the non-passivated ones. The resulting device showed a stabile lifetime, and an EL peak of 470 nm and a maximum EQE of 1.63% were obtained at an operating voltage of 2.6 V and a current density of 0.34 mA/cm2. This work aims to provide a simple method to prepare blue-emitting PQDs and high-performance PQD-based light-emitting devices. [ABSTRACT FROM AUTHOR]

Microorganisms and cancer have always been the fierce enemies of human beings, but the traditional methods of treating them still have many defects. Therefore, it is extremely important to develop rapid, effective and safe treatments. Photodynamic Therapy (PDT) has attracted much attention because of its advantages of non-invasive, non-drug tolerance, high selectivity and low toxicity. As a result, more and more scientists are committed to developing better photosensitizers to enhance the efficiency of PDT in the therapy of microorganisms as well as tumors. The discovery of aggregation-induced emission (AIE) phenomenon provides a novel research direction for the progress of photosensitizer and brings a broader prospect for PDT. This review focuses on the recent progress of photosensitizers (PSs) with AIE properties in PDT from two aspects of anti-microbial and anti-cancer. Among them, anti-microbial aspects were introduced from the perspectives of anti-bacterial, anti-fungal and anti-viral aspects, while anti-cancer aspects were first introduced from the perspective of different target sites of photosensitizers, and then based on the modification of their own structures. Finally, the current limitations, challenges and future development of AIE photosensitizer (AIE-PSs) are clarified in view of the existing strategies and obstacles, so as to promote the development of AIE-PSs in the future clinical applications.

Angiogenesis inhibitor drugs have been explored as important pharmacological agents for cancer therapy, including hepatocellular carcinoma. These agents have several drawbacks, such as drug resistance, nonspecific toxicity, and systemic side effects. Therefore, combination therapy of the drug and small interfering RNA could be a promising option to achieve high therapeutic efficacy while allowing a lower systemic dose. Therefore, we studied adding an alpha-fetoprotein siRNA (AFP-siRNA) incorporated on polymeric nanoparticles (NPs) along with angiogenesis inhibitor drugs. The AFP siRNA-loaded NPs were successfully synthesized at an average size of 242.00 ± 2.54 nm. Combination treatment of AFP-siRNA NPs and a low dose of sunitinib produced a synergistic effect in decreasing cell viability in an in vitro hepatocellular carcinoma (HCC) model. AFP-siRNA NPs together with sorafenib or sunitinib greatly inhibited cell proliferation, showing only 39.29 ± 2.72 and 44.04 ± 3.05% cell viability, respectively. Moreover, quantitative reverse transcription PCR (qRT-PCR) demonstrated that AFP-siRNA incorporated with NPs could significantly silence AFP-mRNA expression compared to unloaded NPs. Interestingly, the expression level of AFP-mRNA was further decreased to 28.53 ± 5.10% when sunitinib was added. Therefore, this finding was considered a new promising candidate for HCC treatment in reducing cell proliferation and enhancing therapeutic outcomes. [ABSTRACT FROM AUTHOR]

In the past two decades, we have witnessed rapid developments in nanotechnology, especially in biomedical applications such as drug delivery, biosensing, and bioimaging. The most commonly used nanomaterials in biomedical applications are nanoparticles, which serve as carriers for various therapeutic and contrast reagents. Since nanomaterials are in direct contact with biological samples, biocompatibility is one of the most important issues for the fabrication and synthesis of nanomaterials for biomedical applications. To achieve specific recognition of biomolecules for targeted delivery and biomolecular sensing, it is common practice to engineer the surfaces of nanomaterials with recognition moieties. This mini-review summarizes different approaches for engineering the interfaces of nanomaterials to improve their biocompatibility and specific recognition properties. We also focus on design strategies that mimic biological systems such as cell membranes of red blood cells, leukocytes, platelets, cancer cells, and bacteria.

When bio-grafts are used in bone healing, interstitial fluid flow (IFF) plays a critical role in both, enhancing bone remodeling and promoting scaffold degradation. Through this enhancement, the fluid will be spread within the network through cells lacuna in equilibrium way promoting osteocytes efficiency, growth factor, and paracrine signaling. The complete adaptation of both microarchitecture bone and scaffold in the transition zone is not possible (No technology of micro-manufacturing is available). However, in our model, the initial bone architecture was extracted from micro-CT. We determine then the dominant flow characteristics (flow magnitude, pressure, orientation, and the carried electrical potential) at the transition zone between native tissue and scaffold. We identify the area where we may have many governing flows escaping from bone not matching with scaffold opening pores. We identify as well, the locations of scaffold pores which do not coincide with enough open lacuna in native tissue, compromising the adequate fluid exchange during osteointegration. By identifying regions of low osteogenesis, we provide a customized pores architecture enhancing flow permeability, driving to spread the fluid energy and the streaming generated potential (SGP) to be in adequate locations. The model may be applied also to evaluate the support for cells migration, cells efficiency, proliferation, differentiation, and growth factors spread. We may promote the exchange of nano particles (NP) as well for carrying anti-microbial properties. However, the scaffold can be designed to promote osteogenesis through the transition region. Results, permit a customized bio-graft design, increasing the options of scaffold architectures with customized pores (position, concentration, and size). The proposed idea, prevent also compromising assembly mechanical stability. [Display omitted] [ABSTRACT FROM AUTHOR]

An interesting hydrogen (H2) gas sensor, synthesized by an indium oxide (In2O3) layer and evaporated palladium (Pd) nanoparticles (NPs), is manufactured and studied. The utilized Pd NPs essentially enhance the surface area/volume (${S}_{A}/{V})$ ratio and catalytic reactivity of the Pd metal. Energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), high-resolution scanning electron microscopy (HRSEM), and TEM were used to investigate the relevant material behaviors of the proposed Pd NP/In2O3 sensor device. The sensing mechanism is explicated in this study. A very high-sensing response of 5243 under 1% H2/air gas with a response time of 12 s and an extremely low-detecting content of 100 ppb H2/air were obtained at the optimal operating temperature of 225 °C. In addition, excellent selectivity toward hydrogen gas is observed for the studied device. The proposed sensor also shows advantages of simple structure, low-cost, and relatively easy fabrication process. [ABSTRACT FROM AUTHOR]

In this study, the effects of zero-valent iron (ZVI) nanoparticles (NPs) on the mechanical performance of cementitious composites were investigated. For this purpose, the use of a novel nanomaterial containing ZVI NPs blended with carboxymethyl cellulose (CMC) and SiO2 was introduced. CMC/SiO2-ZVI NPs were prepared by a green and low-cost sonochemical method at room temperature and characterized using scanning electron microscopy/energy dispersive X-ray spectroscopy, thermal gravimetry analysis, Brunauer–Emmett–Teller, and X-ray diffraction techniques. The values of intrinsic viscosities of CMC/SiO2-ZVI NPs were examined to determine the optimal miscible condition as affected by the different mass ratios of CMC/SiO2 and sonication time. Then, eight different cement mortar specimens containing CMC/SiO2 and CMC/SiO2-ZVI NPs were prepared in ratios of 0.2%, 0.5%, 1%, and 2% by weight, and flexural and compressive strengths of the specimens were determined at the ages of 7 and 28 days. The microstructure of the specimens was also evaluated. Comprehensive results proving the improvement in the mechanical properties have been obtained in the specimens containing 1% and 2% CMC/SiO2-ZVI NPs. [ABSTRACT FROM AUTHOR]

The versatile natural polymer, collagen, has gained vast attention in biomedicine. Due to its biocompatibility, biodegradability, weak antigenicity, biomimetics and well-known safety profile, it is widely used as a drug, protein and gene carrier, and as a scaffold matrix in tissue engineering. Nanoparticles develop favorable chemical and physical properties such as increased drug half-life, improved hydrophobic drug solubility and controlled and targeted drug release. Their reduced toxicity, controllable characteristics of scaffolds and stimuli-responsive behavior make them suitable in regenerative medicine and tissue engineering. Collagen associates and absorbs nanoparticles leading to significant impacts on their biological functioning in any biofluid. This review will discuss collagen nanoparticle preparation methods and their applications and developments in drug delivery systems and tissue engineering. [ABSTRACT FROM AUTHOR]

Perovskite CsPbI3 quantum dots (QDs) were synthesized as a hole-transporting layer (HTL) of a planar perovskite solar cell (PSC). By using the Octam solution during the ligand engineering, CsPbI3 QDs exhibits a denser grain and a larger grain size due to the short-chain ligands of Octam. In addition, CsPbI3 QDs with the Octam solution showed a smooth and uniform surface on MAPbI3 film, indicating the QDs improved the microstructure of the MAPbI3 perovskite film. As a result, the PSC with CsPbI3 QDs as an HTL has the optimal open-circuit voltage as 1.09 V, the short-circuit current as 20.5 mA/cm2, and the fill factor (FF) as 75.7%, and the power conversion efficiency (PCE) as 17.0%. Hence, it is inferred that introducing QDs as a HTL via the ligand engineering can effectively improve the device performance of the PSC.

In this study, blue perovskite quantum dots (PQDs) were prepared using didodecyldimethylammonium bromide (DDAB), which can passivate surface defects caused by the loss of surface ligands and reduce particle size distribution. After the passivation of DDAB, blue CsPbClxBr3−x PQDs dispersed in n-octane produced a more compact and uniform PQD thin film than the non-passivated ones. The resulting device showed a stabile lifetime, and an EL peak of 470 nm and a maximum EQE of 1.63% were obtained at an operating voltage of 2.6 V and a current density of 0.34 mA/cm2. This work aims to provide a simple method to prepare blue-emitting PQDs and high-performance PQD-based light-emitting devices.

A new hydrogen (H2) gas sensor, synthesized with a radio frequency (RF) sputtered cerium oxide (CeO2) thin film and rapid thermal evaporated palladium (Pd) nanoparticles (NPs), is fabricated and reported herein. The employed Pd NPs can effectively increase the surface area/volume (${S}_{A}$ /V) ratio and catalytic reactivity of Pd metal, thereby substantially enhancing the adsorption effect of hydrogen molecules on the device surface and improving the related sensing performance. Energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed to characterize the related properties of the studied device. Experimentally, a high sensing response of 120.2 under 1% H2/air gas at 350 °C with a relatively shorter response (recovery) time of 5 s (17 s) is obtained. The studied Pd NP/CeO2-based sensor device shows wide operating ranges of temperature (200 °C–400 °C) and hydrogen concentration (10 ppm—1% H2/air). A thermodynamic analysis employed to study the surface coverage of hydrogen molecules is reported in this work. The studied sensor device also exhibits the advantages of a simple structure, easy fabrication process, and relatively low cost. [ABSTRACT FROM AUTHOR]

The adverse effects of microplastics (MPs) in aquatic environments have attracted increasing attention and posed health risks along with nanomaterials. Therefore, the toxic effects of polystyrene microplastics (PS-MPs) with different particle sizes (0.07, 0.7 and 7 μm) on zebrafish in the presence and absence of copper nanoparticles (Cu-NPs) were evaluated. The acute toxicity of MPs on zebrafish was 7 μm > 0.07 μm > 0.7 μm. Both 0.07 and 7 μm MPs acted on chromosomes and significantly affected cell cycle process by affecting palmitoyl hydrolase activity; while 0.7 μm MPs acted on extracellular space and significantly affected the activity of endopeptidase inhibitor to affect the cholesterol transport. And 0.07 and 7 μm MPs dominantly affected “cell cycle” pathway by inhibiting DNA replication, delaying the progression of S phase and G2/M phase, and affecting the accurate arrangement and separation of chromosomes; while the 0.7 μm MPs activated numerous platelets to aggregate and adhere in damaged parts, enhanced the coagulation function of platelets, and promoted the formation of fibrin clots, thus abnormally activating the “hemostasis” pathway. The presence of Cu-NPs significantly changed the toxicity-related pathways induced by 7 μm MPs from “cell cycle” into “hemostasis,” but not for the smaller-sized MPs (0.07 and 0.7 μm). The combined exposure of Cu-NPs and 7 μm MPs acted on the extracellular region and significantly affected cholesterol transport by affecting the activity of cholesterol transporters. This study provides theoretical insights for the health risks of MPs to aquatic species and even humans in the actual ecosystem.

Angiogenesis inhibitor drugs have been explored as important pharmacological agents for cancer therapy, including hepatocellular carcinoma. These agents have several drawbacks, such as drug resistance, nonspecific toxicity, and systemic side effects. Therefore, combination therapy of the drug and small interfering RNA could be a promising option to achieve high therapeutic efficacy while allowing a lower systemic dose. Therefore, we studied adding an alpha-fetoprotein siRNA (AFP-siRNA) incorporated on polymeric nanoparticles (NPs) along with angiogenesis inhibitor drugs. The AFP siRNA-loaded NPs were successfully synthesized at an average size of 242.00 ± 2.54 nm. Combination treatment of AFP-siRNA NPs and a low dose of sunitinib produced a synergistic effect in decreasing cell viability in an in vitro hepatocellular carcinoma (HCC) model. AFP-siRNA NPs together with sorafenib or sunitinib greatly inhibited cell proliferation, showing only 39.29 ± 2.72 and 44.04 ± 3.05% cell viability, respectively. Moreover, quantitative reverse transcription PCR (qRT-PCR) demonstrated that AFP-siRNA incorporated with NPs could significantly silence AFP-mRNA expression compared to unloaded NPs. Interestingly, the expression level of AFP-mRNA was further decreased to 28.53 ± 5.10% when sunitinib was added. Therefore, this finding was considered a new promising candidate for HCC treatment in reducing cell proliferation and enhancing therapeutic outcomes.

Pollution by heavy metals represents a significant environmental burden. We employed confocal microscopy with spectral detection and fluorescence lifetime imaging (FLIM) to evaluate the effect of nanoparticles (NPs) from various metals (Zinc, Nickel, Cobalt, Copper) on endogenous fluorescence of Fontinalis antipyretica moss. Short term (3–5 day) exposure to NPs, designed and fabricated by direct synthesis using femtosecond laser ablation in water, was studied. The green flavonoid and/or lignin endogenous fluorescence peaking between 500 and 560 nm was found to be increased by Zn and significantly reduced by Cu. The overall red chlorophyll fluorescence intensity with a maximum of 680 nm remained largely unchanged after exposure to Ni and Zn, but was decreased in the presence of Co and completely abolished by Cu. All NPs but Zn induced changes in the fluorescence lifetimes, demonstrating increased sensitivity of this parameter to environmental pollution. Gathered data indicate fast responsiveness of the endogenous fluorescence in the Fontinalis antipyretica moss to the presence of heavy metals that can thus potentially serve as a biosensing tool for monitoring environmental pollution in the moss natural environment.

Abstract Background Drug resistance of paclitaxel (TAX), the first-line chemotherapy drug for breast cancer, was reported to develop in 90% of patients with breast cancer, especially metastatic breast cancer. Investigating the mechanism of TAX resistance of breast cancer cells and developing the strategy improving its therapeutic efficiency are crucial to breast cancer cure. Methods and Results We here report an elegant nanoparticle (NP)-based technique that realizes efficient breast cancer treatment of TAX. Using lentiviral vector-mediated gene knockdown, we first demonstrated that TAX therapeutic efficiency was closely correlated with metadherin (MTDH) gene expression in breast cancer cell lines. This finding was also supported by efficacy of TAX treatment in breast cancer patients from our clinical studies. Specifically, TAX treatment became more effective when MTDH expression was decreased in MCF-7 cancer cells by the blocking nuclear factor-kappa B (NF-κB) pathway. Based on these findings, we subsequently synthesized a polymeric NP that could co-deliver MTDH-small interfering RNA (MTDH–siRNA) and TAX into the breast cancer tumors in tumor-bearing mice. The NPs were composed of a cationic copolymer, which wrapped TAX in the inside and adsorbed the negatively charged siRNA on their surface with high drug-loading efficiency and good stability. Conclusions NP-based co-delivery approach can effectively knock down the MTDH gene both in vitro and in vivo, which dramatically inhibits breast tumor growth, achieving effective TAX chemotherapy treatment without overt side effects. This study provides a potential therapeutic strategy for the treatment of a wide range of solid tumors highly expressing MTDH.

The versatile natural polymer, collagen, has gained vast attention in biomedicine. Due to its biocompatibility, biodegradability, weak antigenicity, biomimetics and well-known safety profile, it is widely used as a drug, protein and gene carrier, and as a scaffold matrix in tissue engineering. Nanoparticles develop favorable chemical and physical properties such as increased drug half-life, improved hydrophobic drug solubility and controlled and targeted drug release. Their reduced toxicity, controllable characteristics of scaffolds and stimuli-responsive behavior make them suitable in regenerative medicine and tissue engineering. Collagen associates and absorbs nanoparticles leading to significant impacts on their biological functioning in any biofluid. This review will discuss collagen nanoparticle preparation methods and their applications and developments in drug delivery systems and tissue engineering.

The global economic success of man-made nanoscale materials has led to a higher production rate and diversification of emission sources in the environment. For these reasons, novel nanosafety approaches to assess the environmental impact of engineered nanomaterials are required. While studying the potential toxicity of metal nanoparticles (NPs), we realized that gold nanoparticles (AuNPs) have a growth-promoting rather than a stress-inducing effect. In this study we established stable short- and long-term exposition systems for testing plant responses to NPs. Exposure of plants to moderate concentrations of AuNPs resulted in enhanced growth of the plants with longer primary roots, more and longer lateral roots and increased rosette diameter, and reduced oxidative stress responses elicited by the immune-stimulatory PAMP flg22. Our data did not reveal any detrimental effects of AuNPs on plants but clearly showed positive effects on growth, presumably by their protective influence on oxidative stress responses. Differential transcriptomics and proteomics analyses revealed that oxidative stress responses are downregulated whereas growth-promoting genes/proteins are upregulated. These omics datasets after AuNP exposure can now be exploited to study the underlying molecular mechanisms of AuNP-induced growth-promotion.

Nanoparticulate (NP) films and organic photovoltaic devices have been fabricated from poly(3-hexylthiophene):phenyl C61 butyric acid methyl ester (P3HT:PC61BM) NP aqueous dispersions prepared by the precipitation method. The NP inks were stable for more than 4 days, and nanoparticle organic photovoltaic (NP-OPV) devices with efficiency (η) of 1% were fabricated. Detailed analysis of the morphology and performance of the precipitated NP-OPV devices indicated that an optimal blend is responsible for the photocurrent and efficiency observed. These results were confirmed by grazing-incidence x-ray diffraction (GIXRD) analysis, which revealed that the precipitated NPs were resistant to thermal phase segregation, allowing thermal conditioning of the NP films. These results show that precipitated NPs provide a pathway to thermally stable NP-OPV devices with higher photocurrents and efficiencies, approaching those of optimal bulk heterojunction (BHJ) OPV devices. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs), as self-renewing multipotent stromal cells, have been considered promising agents for cancer treatment. A large number of studies have demonstrated the valuable properties of MSC-based treatment, such as low immunogenicity and intrinsic tumor-trophic migratory properties. To enhance the potency of MSCs for therapeutic purposes, equipping MSCs with targeted delivery functions using genetic engineering is highly beneficial. Genetically engineered MSCs can express tumor suppressor agents such as pro-apoptotic, anti-proliferative, anti-angiogenic factors and act as ideal delivery vehicles. MSCs can also be loaded with nanoparticle drugs for increased efficacy and externally moderated targeting. Moreover, exosomes secreted by MSCs have important physiological properties, so they can contribute to intercellular communication and transfer cargo into targeted tumor cells. The precise role of genetically modified MSCs in tumor environments is still up for debate, but the beginning of clinical trials has been confirmed by promising results from preclinical investigations of MSC-based gene therapy for a wide range of malignancies. This review highlights the advanced techniques of engineering/nano-engineering and MSC-derived exosomes in tumor-targeted therapy. [Display omitted] • MSCs, as self-renewing multipotent stromal cells, represent a powerful weapon against cancer. • Engineered MSCs can express tumor suppressor agents. • Loading MSCs with nanoparticle drugs increased efficacy and externally moderated targeting. • Dynamic interactions of MSCs-Ex contribute to intercellular communication and transfer cargo into targeted tumor cells. [ABSTRACT FROM AUTHOR]

Bacteria naturally alter the redox state of many compounds and perform atom-by-atom nanomaterial synthesis to create many inorganic materials. Recent advancements in synthetic biology have spurred interest in using biological systems to manufacture nanomaterials, implementing biological strategies to specify the nanomaterial characteristics such as size, shape, and optical properties. Here, we combine the natural synthetic capabilities of microbes with engineered genetic control circuits toward biogenically synthesized semiconductor nanomaterials. Using an engineered strain of Shewanella oneindensis with inducible expression of the cytochrome complex MtrCAB, we control the reduction of manganese (IV) oxide. Cytochrome expression levels were regulated using an inducer molecule, which enabled precise modulation of dopant incorporation into manganese doped zinc sulfide nanoparticles (Mn:ZnS). Thereby, a synthetic gene circuit controlled the optical properties of biogenic quantum dots. These biogenically assembled nanomaterials have similar physical and optoelectronic properties to chemically synthesized particles. Our results demonstrate the promise of implementing synthetic gene circuits for tunable control of nanomaterials made by biological systems.

A hybrid structure, including 45° sidewalls, a microhole array, and a thin SiO2 nanoparticle (NP)/microsphere (MS) passivation layer, is used to produce GaN-based light-emitting diodes (LEDs). The influences of the microhole depth and SiO2 NP/MS passivation layer on the LED performance are studied. A shallower depth of a microhole array shows better optical properties due to the complete preservation of the GaN/InGaN multiple quantum well (MQW) region. In addition, the use of a thin SiO2 NP/MS passivation layer gives a remarkably reduced reverse-biased leakage current and improved optical performance. Experimentally, under an injection current density of 110 A/cm2, the studied device, with a proper hybrid structure, shows enhancements of 25.9%, 29.2%, and 29.4% in light output power (LOP), external quantum efficiency (EQE), and wall-plug efficiency, respectively, as compared to a LED device with a deeper depth of microhole array. These improvements are mainly caused by the reduced total internal reflection (TIR) and the Fresnel reflection, which increase scattering probability and the opportunity to find photon escape cones. Hence, the studied hybrid structure in this work is a promising route to fabricate high-performance GaN-based LEDs. [ABSTRACT FROM AUTHOR]

A new and high-performance Pd nanoparticle (NP)/WO3 thin-film-based sensor is fabricated by vacuum thermal evaporation (VTE) and RF sputtering herein. Based on the remarkable catalytic activity of Pd NPs and high-quality WO3 thin film (20 nm in thickness), excellent hydrogen sensing properties, including a very high sensing response of $\textbf {1.8}\times \textbf {10}^{\textbf {4}}$ (in 1000 ppm H2/air gas at 175°C), an extremely low detecting level (≤5 ppm H2/air), a relatively low optimal operating temperature of 175°C, and a fast sensing speed, are obtained. In addition, the studied Pd NP/WO3-based device shows the advantages of simple structure, low cost, and easy fabrication process. The studied device is, therefore, promising for high-performance hydrogen sensing applications. [ABSTRACT FROM AUTHOR]

Bacteria naturally alter the redox state of many compounds and perform atom-by-atom nanomaterial synthesis to create many inorganic materials. Recent advancements in synthetic biology have spurred interest in using biological systems to manufacture nanomaterials, implementing biological strategies to specify the nanomaterial characteristics such as size, shape, and optical properties. Here, we combine the natural synthetic capabilities of microbes with engineered genetic control circuits toward biogenically synthesized semiconductor nanomaterials. Using an engineered strain of Shewanella oneindensis with inducible expression of the cytochrome complex MtrCAB, we control the reduction of manganese (IV) oxide. Cytochrome expression levels were regulated using an inducer molecule, which enabled precise modulation of dopant incorporation into manganese doped zinc sulfide nanoparticles (Mn:ZnS). Thereby, a synthetic gene circuit controlled the optical properties of biogenic quantum dots. These biogenically assembled nanomaterials have similar physical and optoelectronic properties to chemically synthesized particles. Our results demonstrate the promise of implementing synthetic gene circuits for tunable control of nanomaterials made by biological systems. [ABSTRACT FROM AUTHOR]

Abstract Messenger RNA-based vaccines have the potential to trigger robust cytotoxic immune responses, which are essential for fighting cancer and infectious diseases like HIV. Dendritic Cells (DCs) are choice targets for mRNA-based vaccine strategies, as they link innate and adaptive immune responses and are major regulators of cytotoxic and humoral adaptive responses. However, efficient delivery of antigen-coding mRNAs into DC cytosol has been highly challenging. In this study, we developed an alternative to lipid-based mRNA delivery systems, using poly(lactic acid) nanoparticles (PLA-NPs) and cationic cell-penetrating peptides as mRNA condensing agent. The formulations are assembled in two steps: (1) formation of a polyplex between mRNAs and amphipathic cationic peptides (RALA, LAH4 or LAH4-L1), and (2) adsorption of polyplexes onto PLA-NPs. LAH4-L1/mRNA polyplexes and PLA-NP/LAH4-L1/mRNA nanocomplexes are taken up by DCs via phagocytosis and clathrin-dependent endocytosis, and induce strong protein expression in DCs in vitro. They modulate DC innate immune response by activating both endosome and cytosolic Pattern Recognition Receptors (PRRs), and induce markers of adaptive responses in primary human DCs in vitro , with prevalent Th1 signature. Thus, LAH4-L1/mRNA and PLA-NP/LAH4-L1/mRNA represent a promising platform for ex vivo treatment and mRNA vaccine development. [ABSTRACT FROM AUTHOR]

The characteristics of GaN-based light-emitting diodes (LEDs) with a hybrid structure incorporating a microhole array, 45 sidewalls, and an appropriate SiO2 nanoparticle (NP)/microsphere (MSs) passivation layer are studied and reported. The use of a SiO2 NP/MSs passivation layer causes a remarkable reduction in reverse-biased leakage current. The employment of this hybrid structure leads to substantial enhancements in optical properties without any degradation in electrical performance. In addition, a lower content of SiO2 NP in the mixed SiO2 NP/MSs solution leads to enhanced optical behavior due to the improved transmittance. Experimentally, as compared with a conventional LED (Device A), the studied Device E shows 50.6%, 50.9%, 48.4%, and 49.9% enhancements in light output power, luminous flux, luminous efficacy, and wall-plug efficiency, respectively. These advantages are mainly attributed to the increased scattering probability and the opportunity to find photon escape cones as well as the reduced total internal reflection and Fresnel reflection effects. Therefore, the studied hybrid structure provides a promise for high-performance GaN-based LED applications. [ABSTRACT FROM AUTHOR]

Many nano/microparticles (n/µP), to which our body is exposed, have no physiological way of removal. Our immune system sense these “small particulate objects”, and tries to decrease their harmfulness. Since oxidation, phagocytosis and other methods of degradation do not work with small, chemically resistant, and hydrophobic nanoparticles (nP). This applies to soot from air pollution, nano-diamonds from cosmic impact, polishing and related machines, synthetic polymers, and dietary n/µP. Our body tries to separate these from the surrounding tissue using aggregates from neutrophil extracellular traps (NETs). This effectively works in soft tissues where n/µP are entrapped into granuloma-like structures and isolated. The interactions of hydrophobic nanocrystals with circulating or ductal patrolling neutrophils and the consequent formation of occlusive aggregated NETs (aggNETs) are prone to obstruct capillaries, bile ducts in gallbladder and liver, and many more tubular structures. This may cause serious health problems and often fatality. Here we describe how specific size and surface properties of n/µP can activate neutrophils and lead to aggregation-related pathologies. We discuss “natural” sources of n/µP and those tightly connected to unhealthy diets.

Once inhaled, nanoparticles (NPs) will first interact with lung surfactant system, which may influence the colloidal aspects of NPs and consequently the toxic potential of NPs to pulmonary cells. In this study, we investigated the effects of dipalmitoyl phosphatidylcholine (DPPC), the major component in lung surfactant, on stability and toxicity of ZnO NPs. The presence of DPPC increased the UV–vis spectra, hydrodynamic size, Zeta potential and dissolution rate of ZnO NPs, which indicates that DPPC might interact with NPs and affect the colloidal stability of NPs. Exposure to ZnO NPs induced cytotoxicity associated with increased intracellular Zn ions but not superoxide in A549 cells. In A549 epithelium model, exposure to ZnO NPs induced cytotoxicity and decreased the release of interleukin 6 (IL-6) without a significant effect on epithelial permeability rate. Co-exposure of A549 cells or A549 epithelium model to DPPC and ZnO NPs induced a higher release of lactate dehydrogenase (LDH) and interleukin-6 (IL-6) compared with the exposure of ZnO NPs alone. We concluded that the presence of DPPC could influence the colloidal stability of ZnO NPs and increase the damage of NPs to membrane probably due to the increased positive surface charge. [ABSTRACT FROM AUTHOR]

Understanding the mechanism of nanoparticle (NP) induced toxicity is important for nanotoxicological and nanomedicinal studies. Endoplasmic reticulum (ER) is a crucial organelle involved in proper protein folding. High levels of misfolded proteins in the ER could lead to a condition termed as ER stress, which may ultimately influence the fate of cells and development of human diseases. In this review, we summarized studies about effects of NP exposure on ER stress. A variety of NPs, especially metal-based NPs, could induce morphological changes of ER and activate ER stress pathway both in vivo and in vitro . In addition, modulation of ER stress by chemicals has been shown to alter the toxicity of NPs. These studies in combination suggested that ER stress could be the mechanism responsible for NP induced toxicity. Meanwhile, nanomedicinal studies also used ER stress inducing NPs or NPs loaded with ER stress inducer to selectively induce ER stress mediated apoptosis in cancer cells for cancer therapy. In contrast, alleviation of ER stress by NPs has also been shown as a strategy to cure metabolic diseases. In conclusion, exposure to NPs may modulate ER stress, which could be a target for future nanotoxicological and nanomedicinal studies. [ABSTRACT FROM AUTHOR]

Researchers have applied mesenchymal stem cells (MSC) to a variety of therapeutic scenarios by harnessing their multipotent, regenerative, and immunosuppressive properties with tropisms toward inflamed, hypoxic, and cancerous sites. Although MSC-based therapies have been shown to be safe and effective to a certain degree, the efficacy remains low in most cases when MSC are applied alone. To enhance their therapeutic efficacy, researchers have equipped MSC with targeted delivery functions using genetic engineering, therapeutic agent incorporation, and cell surface modification. MSC can be genetically modified virally or non-virally to overexpress therapeutic proteins that complement their innate properties. MSC can also be primed with non-peptidic drugs or magnetic nanoparticles for enhanced efficacy and externally regulated targeting, respectively. Furthermore, MSC can be functionalized with targeting moieties to augment their homing toward therapeutic sites using enzymatic modification, chemical conjugation, or non-covalent interactions. These engineering techniques are still works in progress, requiring optimization to improve the therapeutic efficacy and targeting effectiveness while minimizing any loss of MSC function. In this review, we will highlight the advanced techniques of engineering MSC, describe their promise and the challenges of translation into clinical settings, and suggest future perspectives on realizing their full potential for MSC-based therapy. [ABSTRACT FROM AUTHOR]

Highlights: [•] CdS QDs were cytotoxic for mussel hemocytes and gill cells in vitro. [•] Ionic Cd was the most toxic form, followed by CdS QDs and bulk CdS. [•] CdS QDs altered oxidative balance and caused DNA damage in mussel cells. [•] CdS QDs caused a particle-specific immunostimulation on phagocytosis of hemocytes. [•] Conceptual models for cellular handling and toxicity of CdS QDs are proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Summarizing current applications of nanomaterials in protein kinase assays. [•] Classifying kinase nano-sensors according to analytical techniques. [•] Discussing the relative advantages and the limitations of these methods. [•] Predicting the trend in future development of nanomaterial-based kinase biosensors. [ABSTRACT FROM AUTHOR]

Highlights: [•] BSA and C-BSA conjugated ultrasmall Gd2O3 nanoparticles were synthesized. [•] BSA can bind many ultrasmall Gd2O3 nanoparticles whereas C-BSA cannot. [•] Large water proton relaxivities were observed. [•] High contrast MR images in a mouse liver after intravenous injection were observed. [•] These nanoparticles are potential MRI contrast agents. [ABSTRACT FROM AUTHOR]

Abstract: Drug delivery via the hair follicle (HF) especially with nanoparticles (NP) recently gained attention due to a depot effect and facilitated absorption conditions within the lower HF. With the prospect of transdermal drug delivery, it is of interest to optimize the follicular uptake of NP. In this study, a method was developed to quantify NP uptake into HF and applied in vitro in a pig ear model and in vivo in human volunteers. The influence of NP material on HF uptake was investigated using fluorescence-labeled NP based on poly(d,l-lactide-co-glycolide) (PLGA). All NP had similar hydrodynamic sizes (163–170nm) but different surface modifications: (i) plain PLGA, (ii) chitosan-coated PLGA (Chit.-PLGA), and (iii) Chit.-PLGA coated with different phospholipids (PL) (DPPC (100), DPPC:Chol (85:15), and DPPC:DOTAP (92:8). Differential stripping was performed, including complete mass balance. The samples were extracted for fluorescence quantification. An effect of the PL coating on follicular uptake was observed as DPPC (100) and DPPC:DOTAP (92:8) penetrated into HF to a higher extent than the other tested NP. The effect was observed both in the pig ear model as well as in human volunteers, although it was statistically significant only in the in vitro model. An excellent in vitro–in vivo correlation (IVIVC, r 2 =0.987) between both models was demonstrated, further supporting the suitability of the pig ear model as a surrogate for the in vivo situation in humans for quantifying NP uptake into HF. These findings may help to optimize NP for targeting the HF and to improve transdermal delivery. [Copyright &y& Elsevier]

Highlights: [•] DAB photo-conversion to detect very small amounts of fluorochromes at TEM. [•] Ultrastructural visualization of photoactive molecules in cell organelles and cytosol. [•] Reliable detection at TEM of electron-transparent fluorescent nanoparticles. [•] Simultaneous application of DAB photoconversion and gold immunolabeling. [ABSTRACT FROM AUTHOR]

The potential environmental toxicities of several metal oxide nanoparticles (NPs; CuO, TiO, NiO, FeO, ZnO, and CoO) were evaluated in the context of bioluminescence activity, seed germination, and bacterial gene mutation. The bioassays exhibited different sensitivities, i.e., each kind of NP exhibited a different level of toxicity in each of the bioassays. However, with a few exceptions, CuO and ZnO NPs had most toxic for germination of Lactuca seed (EC 0.46 mg CuO/l) and bioluminescence (EC 1.05 mg ZnO/l). Three NPs (CoO, TiO, and FeO) among all tested concentrations (max. 1,000 mg/l) showed no inhibitory effects on the tested organisms, except for CoO NPs on bioluminescence activity (EC 62.04 mg/l). The sensitivity of Lactuca seeds was greater than that of Raphanus seeds (EC 0.46 mg CuO/l versus 26.84 mg CuO /l ). The ranking of metal toxicity levels on bioluminescence was in the order of ZnO > CuO > CoO > NiO > FeO, TiO, while CuO > ZnO > NiO > CoO, FeO, TiO on germination. No revertant mutagenic ratio (greater than 2.0) of Salmonella typhimurium TA 98 was observed under any tested condition. These findings demonstrate that several bioassays, as opposed to any single one, are needed for the accurate assessment of NP toxicity on ecosystems. [ABSTRACT FROM AUTHOR]