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Red color-emitting CaGd2ZnO5:Eu3+ (CGZO:Eu3+) nanophosphors were synthesized by a facile sol–gel process. The structural and luminescent properties of these phosphors were investigated as a function of annealing temperature and Eu3+ ion concentration. The orthorhombic phase was confirmed at different annealing temperatures, showing an irregular morphology within the nanoscale range. Photoluminescence (PL) excitation spectra of CGZO:Eu3+ showed host absorption band (HAB), charge transfer band (CTB), and intense f–f transitions of Eu3+ in the violet and blue wavelength regions. The CTB intensity increased and the HAB intensity decreased with increasing annealing temperature or Eu3+ ion concentration. The CGZO:Eu3+ exhibited a strong absorption in the blue region as compared to the CTB and had a superior property compared to available commercial phosphors. This feature facilitates the fabrication of high color rendering index white light-emitting diodes for display systems. In PL spectra, an intense red emission was observed due to the hypersensitive 5D0→7F2 transition with good asymmetry ratio and chromaticity coordinates. Optimized annealing temperature and concentration of Eu3+ ions were observed for CGZO host lattice based on the 466 nm excitation wavelength. The cathodoluminescent properties were also similar to the PL results. [ABSTRACT FROM AUTHOR]

Trivalent lanthanide (Eu3+, Tb3+ and Dy3+) ions activated tunable color emitting BaGd2O4 (BG) phosphors were synthesized by a facile Pechini-type sol–gel process. The X-ray diffraction pattern confirmed the orthorhombic phase after annealing at 1300 °C for 5 h. Morphological studies were performed based on the analysis of transmission electron microscopy images, which showed needle type nanorods. The BG phosphor exhibited good photoluminescence (PL) properties in the respective regions when doped with Eu3+, Tb3+ and Dy3+ ions. The Eu3+ co-activated BG:Tb3+ phosphor yielded tunable emissions including tri-band established white light emission based on the co-activator concentration and excitation wavelength. The energy transfer from Tb3+ to Eu3+ ions was controlled by selecting a suitable excitation wavelength and the decay measurements were carried out for analyzing the energy transfer efficiency. The cathodoluminescence properties of these phosphors were almost similar to PL properties when doped with individual Eu3+, Tb3+, and Dy3+ ions, but were different when co-doped with Eu3+/Tb3+ or Eu3+/Dy3+ ions. In the case of Eu3+/Tb3+ doped samples, the energy transfer process occurred unlike the PL channel. The calculated Commission International de l'Eclairage chromaticity coordinates of individual ion doped BG phosphors confirmed red, green, and white emissions and for co-doped samples they showed tunable emission. [ABSTRACT FROM AUTHOR]

RE3+ (Er3+/Tm3+/Yb3+) ions tri-doped SrY2O4 nanocrystalline phosphors were synthesized by a citrate sol–gel method. After annealing at 1300 °C, the structure was identified to be pure orthorhombic and the particles were found to be nearly spherical in shape. The up-conversion emission spectra of the SrY2O4:1Er3+ phosphor revealed a bright green emission (4S3/2→4I15/2) around 551 nm. To enhance the red emission of the Er3+ ions, Yb3+ ions were co-doped with Er3+ ions, leading to a greenish yellow emission under 980 nm excitation. In the case of the 1Er3+/1Tm3+/3Yb3+ ions tri-doped phosphor, white-light emission was observed corresponding to the 1G4→3H6 (Tm3+), 4S3/2→4I15/2 (Er3+) and 4F9/2→4I15/2 (Er3+) transitions at 487, 551 and 664 nm, respectively. It was interestingly noticed that, when the exciting pump power was changed from 100 to 900 mW, the blue emission band of the Tm3+ ions was enhanced by the suppression of the red and green emission bands of the Er3+ ions so that the chromaticity coordinates were also moved to the cyan emission region. This feature suggests that the Er3+ ion may also act as a sensitizer for the Tm3+ and Yb3+ ions and a possible energy transfer mechanism was also discussed. [ABSTRACT FROM AUTHOR]

Tm3+/Er3+/Eu3+/Er3+, Tm3+/Er3+/Eu3+ single, double and triple activator ion/ions doped nanocrystalline BaGd2O4 (BG) phosphors were prepared by a Pechini type sol-gel process. After annealing at 1300 °C, X-ray diffraction patterns confirmed their orthorhombic structure. Field-emission transmission electron microscope images of the BG sample indicated a nanoneedle-type morphology. Photoluminescence (PL) and cathodoluminescence (CL) measurements were utilized to establish the emission properties of rare-earth ions doped nanocrystalline BG host lattice. Under near-ultraviolet (NUV) excitations, BG:Tm3+ and BG:Er3+ exhibited their characteristic emissions in the blue and green regions, respectively, while BG:Tm3+/Er3+ and BG:Tm3+/Er3+/Eu3+ showed cyan and white light emissions, respectively, when doped with appropriate amounts of activator ions. In the PL, the cross-relaxation process is dominant rather than the energy transfer process. Due to the different mechanism from PL, the CL spectra showed different emission features of BG: Tm3+/Er3+/Eu3+ phosphor. The CL spectra of BG:Tm3+ and BG:Er3+ established the high purity blue and green emissions, respectively. From the PL and CL investigations, the white-light emission was realized from the single-phase BG:Tm3+/Er3+/Eu3+ phosphor under NUV and low voltage electron beam excitations. [ABSTRACT FROM AUTHOR]

Mesoporous particles are emerging as multifunctional biomaterials for imaging and drug delivery in several disease models, including cancer. We developed PEGylated α-Gd2(MoO4)3 marigold flower-like mesoporous particles for the purpose of drug delivery and, more specifically, evaluated their ability to deliver curcumin. The obtained mesoporous particles significantly conjugated the curcumin particles on their surfaces by inducing the formation of curcumin nanoparticles. In vitro studies of the PEGylated mesoporous particles filled with curcumin demonstrated that these particles could considerably facilitate the continuous and sustained release of curcumin into the cytoplasm and nucleus. As a result, the intracellular release of curcumin can inhibit proliferation in two human pancreatic cancer cell lines: MIA PaCa-2 and PANC-1. Additionally, the particles showed the increased inhibition of pIKKα, pIKKα/β and NF- κB-DNA binding activity as compared to pure curcumin. The curcumin conjugated mesoporous particles are concentrated in the cytoplasm and nucleus of the treated cancer cell lines. Consequently, these mesoporous particles are an effective method for drug delivery that can cross the biological barriers of the body targeting the cellular nucleoplasm. [ABSTRACT FROM AUTHOR]

Trivalent rare-earth (RE3+ = Eu3+, Tb3+, Dy3+, and Sm3+) ions activated Gd2O(CO3)2·H2O chrysanthemum-like flowers are prepared by a modified urea-based homogeneous precipitation via a template free hydrothermal synthesis route. Subsequently, Gd2O3 monodispersed spheres were obtained after calcining at 750 °C. The growth mechanism of the Gd2O(CO3)2·H2O:RE3+ chrysanthemum-like morphology (homogeneous precipitation) and their transformation to monodispersed spheres (heterogeneous nucleation) are established by taking scanning electron microscope and transmission electron microscope images of the intermediate products. The thermogravimetric analysis, Fourier transform infrared analyses confirmed the decomposition of CO2 and OH groups, and the corresponding XRD patterns exhibited the Gd2O(CO3)2·H2O and cubic Gd2O3 phases. The photoluminescence measurements are used to explore the emission behavior of different RE3+ ions activated Gd2O3 spheres. The Gd2O3:Eu3+ shows gorgeous red emission with high purity red color as compared to the commercial Y2O3:Eu3+ phosphors. Gd2O3:Tb3+, Gd2O3:Dy3+ and Gd2O3:Sm3+ exhibit green, yellow and rich orange emissions, respectively. The Tb3+/Eu3+ co-doped sample shows warm white light by controlling the energy transfer. At minimal parameters, the cathodoluminescence intensity of Gd2O3:Eu3+ is beyond the experimental limit for 5 kV of accelerating voltage. The CIE chromaticity coordinates were also calculated from the PL and CL spectra of RE3+ ions to establish their color richness. [ABSTRACT FROM AUTHOR]

Pyrochlore-structured yttrium titanate phosphors activated by trivalent europium ions (Y2Ti2O7(YT):Eu3+), with spherical morphology, were synthesized at different pH values by a solvothermal process. From the structural and morphological measurements, the annealing temperature had no effect on the spherical morphology of the YT:Eu3+ sample. The photoluminescence excitation and emission spectra were taken by activating the Eu3+ ions in the YT host lattice as functions of Eu3+ ion concentration and annealing temperature. The optimal doping concentration was found to be 4 mol%, exhibiting an excellent orange-red emission due to the highest intensity of the 5D0 → 7F1 transition. When the YT:Eu3+ phosphor was mixed with YAG:Ce3+ phosphor, a brilliant white light emission was achieved. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

White light-emitting diode (WLED) products currently available on the market are based on the blue LED combined with yellow phosphor approach. However, these WLEDs are still insufficient for general illumination and flat panel display (FPD) applications because of their low color-rendering index (CRI < 75) and high correlated color temperature (CCT = 6000 K). Although near-ultraviolet (UV) LED chips provide more efficient excitation than blue chips, YAG:Ce3+ phosphors have very weak excitation in the near-UV spectral region. Hence, there is an increasing demand for novel yellow phosphor materials with excitation in the near-UV region. In this work, we report novel self-activated yellow Ca5Zn3.92In0.08(V0.99Ta0.01O4)6 (CZIVT) phosphors that efficiently convert near-UV excitation light into yellow luminescence. The crystal structure and lattice parameters of these CZIVT phosphors are elucidated through Rietveld refinement. Through doping with In3+ and Ta5+ ions, the emission intensity is enhanced in the red region, and the Stokes shift is controlled to obtain good color rendition. When a near-UV LED chip is coated with a combination of CZIVT and commercial blue Ba0.9Eu0.1MgAl10O17 phosphors, a pleasant WLED with a high CRI of 82.51 and a low CCT of 5231 K, which are essential for indoor illumination and FPDs, is achieved. [ABSTRACT FROM AUTHOR]

Background: 1,25(OH) 2 D 3 is a fat-soluble vitamin, involved in regulating Ca 2+ homeostasis in the body. Its storage in adipose tissue depends on the fat content of the body. Obesity is the result of abnormal lipid deposition due to the prolonged positive energy balance and increases the risk of several cancer types. Furthermore, it has been associated with vitamin D deficiency and defined as a low 25(OH) 2 D 3 blood level. In addition, 1,25(OH) 2 D 3 plays vital roles in Ca 2+ -P i and glucose metabolism in the adipocytes of obese individuals and regulates the expressions of adipogenesis-associated genes in mature adipocytes., Scope and Approach: The present contribution focused on the VDR mediated mechanisms interconnecting the obese condition and cancer proliferation due to 1,25(OH) 2 D 3 -deficiency in humans. This contribution also summarizes the identification and development of molecular targets for VDR-targeted drug discovery., Key Findings and Conclusions: Several studies have revealed that cancer development in a background of 1,25(OH) 2 D 3 deficient obesity involves the VDR gene. Moreover, 1,25(OH) 2 D 3 is also known to influence several cellular processes, including differentiation, proliferation, and adhesion. The multifaceted physiology of obesity has improved our understanding of the cancer therapeutic targets. However, currently available anti-cancer drugs are notorious for their side effects, which have raised safety issues. Thus, there is interest in developing 1,25(OH) 2 D 3 -based therapies without any side effects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Sickle cell disease (SCD) is the most severe monogenic hemoglobinopathy caused by a single genetic mutation that leads to repeated polymerization and depolymerization of hemoglobin resulting in intravascular hemolysis, cell adhesion, vascular occlusion, and ischemia-reperfusion injury. Hemolysis causes oxidative damage indirectly by generating reactive oxygen species through various pathophysiological mechanisms, which include hemoglobin autoxidation, endothelial nitric oxide synthase uncoupling, reduced nitric oxide bioavailability, and elevated levels of asymmetric dimethylarginine. Red blood cells have a built-in anti-oxidant system that includes enzymes like sodium dismutase, catalase, and glutathione peroxidase, along with free radical scavenging molecules, such as vitamin C, vitamin E, and glutathione, which help them to fight oxidative damage. However, these anti-oxidants may not be sufficient to prevent the effects of oxidative stress in SCD patients. Therefore, in line with a recent FDA request that the focus to be placed on the development of innovative therapies for SCD that address the root cause of the disease, there is a need for therapies that target oxidative stress and restore redox balance in SCD patients. This review summarizes the current state of knowledge regarding the role of oxidative stress in SCD and the potential benefits of anti-oxidant therapies. It also discusses the challenges and limitations of these therapies and suggests future directions for research and development., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Breast cancer (BC) is the second most fatal disease and is the prime cause of cancer allied female deaths. BC is caused by aberrant tumor suppressor genes and oncogenes regulated by transcription factors (TFs) like NF-κB. NF-κB is a pro-inflammatory TF that crucially alters the expressions of various genes associated with inflammation, cell progression, metastasis, and apoptosis and modulates a network of genes that underlie tumorigenesis. Herein, we focus on NF-κB signaling pathways, its regulators, and the rationale for targeting NF-κB. This review also includes TFs that maintain NF-κB crosstalk and their roles in promoting angiogenesis and metastasis. In addition, we discuss the importance of combination therapies, resistance to treatment, and potential novel therapeutic strategies including nanomedicine that targets NF-κB., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

HOX transcript antisense intergenic RNA (HOTAIR) is an oncogenic non-coding RNA whose expression is strongly correlated with the tumor grade and prognosis of a variety of carcinomas including breast cancer (BC). HOTAIR regulates various target genes via sponging and epigenetic mechanisms and controls various oncogenic cellular and signaling mechanisms including metastasis and drug resistance. In BC cells, HOTAIR expression is regulated by a variety of transcriptional and epigenetic mechanisms. In this review, we describe the regulatory mechanisms that govern HOTAIR expression during cancer development and explore how HOTAIR drives BC development, metastasis, and drug resistance. In the final section of this review, we focus on the role of HOTAIR in BC management, therapeutic treatment, and prognosis, highlighting its potential therapeutic applications., (© 2023. The Author(s).)

Quantum dots (QDs) have an unparalleled ability to mimic true colors due to their size-tunable optical and electronic properties, which make them the most promising nanoparticles in various fields. Currently, the majority of QDs available in the market are cadmium, indium, and lead-based materials but the toxicity and unstable nature of these QDs restricts their industrial and practical applications. To avoid using heavy metal ions, especially cadmium, the current research is focused on the fabrication of perovskite and vanadate QDs. Herein, we report the facile synthesis of a novel and cost-effective CsVO 3 QDs for the first time. The sizes of the CsVO 3 QDs produced were tuned from 2 to 10 nm by varying the reaction temperature from 140 to 190 °C. On increasing QD size, a continuous red shift was observed in absorption and emission spectra, signifying the presence of quantum confinement. In addition, along with CsVO 3 QDs, the CsVO 3 nanosheets self-assembled microflower-like particles were found as residue after the centrifugation; the X-ray diffraction indicated an orthorhombic structure. Under 365 nm excitation, these CsVO 3 microflower-like particles exhibited broad emission with CIE coordinates in the white emission region. The acquired results suggest that CsVO 3 QDs may represent a new class of cadmium-free materials for optoelectronic and biomedical applications.

In recent times, upconversion nanomaterials with mesoporous hollow structures have gained significant interest as a prospective nano-platform for cancer imaging and therapeutic applications. In this study, we report a highly biocompatible YVO 4 :1Er 3+ /10Yb 3+ upconversion mesoporous hollow nanospheriods (YVO 4 :Er 3+ /Yb 3+ UC-MHNSPs) by a facile and rapid self-sacrificing template method. The Rietveld analysis confirmed their pure phase of tetragonal zircon structure. Nitrogen adsorption-desorption isotherms revealed the mesoporous nature of these UC-MHNSPs and the surface area is found to be ~87.46 m 2 /g. Under near-infrared excitation (980 nm), YVO 4 :Er 3+ /Yb 3+ UC-MHNSPs showed interesting color tunability from red to green emission. Initially (at 0.4 W), energy back transfer from Er 3+ to Yb 3+ ions leads to the strong red emission. Whereas at high pump powers (1 W), a fine green emission is observed due to the dominant three-photon excitation process and traditional energy transfer route from Er 3+ to Yb 3+ ions. The bright red light from the membrane of HeLa cells confirmed the effective cellular uptake of YVO 4 :Er 3+ /Yb 3+ UC-MHNSPs. The resonant decrease in cell viability on increasing the concentration of curcumin conjugated YVO 4 :Er 3+ /Yb 3+ UC-MHNSPs established their excellent antitumor activity. Therefore, the acquired results indicate that these YVO 4 :Er 3+ /Yb 3+ UC-MHNSPs are promising drug carriers for bioimaging and various therapeutic applications.

The tumor microenvironment (TME) plays a key role in cancer development and emergence of drug resistance. TME modulation has recently garnered attention as a potential approach for reprogramming the TME and resensitizing resistant neoplastic niches to existing cancer therapies such as immunotherapy or chemotherapy. Nano-based solutions have important advantages over traditional platform and can be specifically targeted and delivered to desired sites. This review explores novel nano-based approaches aimed at targeting and reprogramming aberrant TME components such as macrophages, fibroblasts, tumor vasculature, hypoxia and ROS pathways. We also discuss how nanoplatforms can be combined with existing anti-tumor regimens such as radiotherapy, immunotherapy, phototherapy or chemotherapy to enhance clinical outcomes in solid tumors., (© 2022. The Author(s).)

Colorectal cancer (CRC) is one of the deadliest diseases worldwide due to a lack of early detection methods and appropriate drug delivery strategies. Conventional imaging techniques cannot accurately distinguish benign from malignant tissue, leading to frequent misdiagnosis or diagnosis at late stages of the disease. Novel screening tools with improved accuracy and diagnostic precision are thus required to reduce the mortality burden of this malignancy. Additionally, current therapeutic strategies, including radio- and chemotherapies carry adverse side effects and are limited by the development of drug resistance. Recent advances in nanotechnology have rendered it an attractive approach for designing novel clinical solutions for CRC. Nanoparticle-based formulations could assist early tumor detection and help to overcome the limitations of conventional therapies including poor aqueous solubility, nonspecific biodistribution and limited bioavailability. In this review, we shed light on various types of nanoparticles used for diagnosis and drug delivery in CRC. In addition, we will explore how these nanoparticles can improve diagnostic accuracy and promote selective drug targeting to tumor sites with increased efficiency and reduced cytotoxicity against healthy colon tissue., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Female-specific cancers are the most common cancers in women worldwide. Early detection methods remain unavailable for most of these cancers, signifying that most of them are diagnosed at later stages. Furthermore, current treatment options for most female-specific cancers are surgery, radiation and chemotherapy. Although important milestones in molecularly targeted approaches have been achieved lately, current therapeutic strategies for female-specific cancers remain limited, ineffective and plagued by the emergence of chemoresistance, which aggravates prognosis. Recently, the application of nanotechnology to the medical field has allowed the development of novel nano-based approaches for the management and treatment of cancers, including female-specific cancers. These approaches promise to improve patient survival rates by reducing side effects, enabling selective delivery of drugs to tumor tissues and enhancing the uptake of therapeutic compounds, thus increasing anti-tumor activity. In this review, we focus on the application of nano-based technologies to the design of novel and innovative diagnostic and therapeutic strategies in the context of female-specific cancers, highlighting their potential uses and limitations., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cancer is an outrageous disease with uncontrolled differentiation, growth, and migration to the other parts of the body. It is the second-most common cause of death both in the U.S. and worldwide. Current conventional therapies, though much improved and with better prognosis, have several limitations. Chemotherapeutic agents, for instance, are cytotoxic to both tumor and healthy cells, and the non-specific distribution of drugs at tumor sites limits the dose administered. Nanotechnology, which evolved from the coalescence and union of varied scientific disciplines, is a novel science that has been the focus of much research. This technology is generating more effective cancer therapies to overcome biomedical and biophysical barriers against standard interventions in the body; its unique magnetic, electrical, and structural properties make it a promising tool. This article reviews endogenous- and exogenous-based stimulus-responsive drug delivery systems designed to overcome the limitations of conventional therapies. The article also summarizes the study of nanomaterials, including polymeric, gold, silver, magnetic, and quantum dot nanoparticles. Though an array of drug delivery systems has so far been proposed, there remain many challenges and concerns that should be addressed in order to fill the gaps in the field. Prominence is given to drug delivery systems that employ external- and internal-based stimuli and that are emerging as promising tools for cancer therapeutics in clinical settings., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cancer theranostics represents a strategy that aims at combining diagnosis with therapy through the simultaneous imaging and targeted delivery of therapeutics to cancer cells. Recently, the folate receptor alpha has emerged as an attractive theranostic target due to its overexpression in multiple solid tumors and its great functional versatility. In fact, it can be incorporated into folate-conjugated nano-systems for imaging and drug delivery. Hence, it can be used along the line of personalized clinical strategies as both an imaging tool and a delivery method ensuring the selective transport of treatments to tumor cells, thus highlighting its theranostic qualities. In this review, we will explore these theranostic characteristics in detail and assess their clinical potential. We will also discuss the technological advances that have allowed the design of sophisticated folate-based nanocarriers harboring various chemical properties and suited for the transport of various therapeutic agents., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The glycoprotein FRα is a membrane-attached transport protein that is shielded from the immune system in healthy cells. However, it is upregulated in various malignancies, involved in cancer development and is also immunogenic. Furthermore, FRα is a tumor-associated antigen endowed with unique properties, thus rendering it a suitable target for immunotherapeutic development in cancer. Various anti- FRα immunotherapeutic strategies are thus currently being developed and clinically assessed for the treatment of various solid tumors. These approaches include passive anti-FRα immunotherapies, such as monoclonal antibodies, or active immunotherapies, such as CART, folate haptens and vaccines. In this review, we will explore the advances in the field of FRα-based immune therapies and discuss both their successes and shortcomings in the clinical setting., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Trivalent lanthanide (Eu(3+), Tb(3+) and Dy(3+)) ions activated tunable color emitting BaGd2O4 (BG) phosphors were synthesized by a facile Pechini-type sol-gel process. The X-ray diffraction pattern confirmed the orthorhombic phase after annealing at 1300 °C for 5 h. Morphological studies were performed based on the analysis of transmission electron microscopy images, which showed needle type nanorods. The BG phosphor exhibited good photoluminescence (PL) properties in the respective regions when doped with Eu(3+), Tb(3+) and Dy(3+) ions. The Eu(3+) co-activated BG:Tb(3+) phosphor yielded tunable emissions including tri-band established white light emission based on the co-activator concentration and excitation wavelength. The energy transfer from Tb(3+) to Eu(3+) ions was controlled by selecting a suitable excitation wavelength and the decay measurements were carried out for analyzing the energy transfer efficiency. The cathodoluminescence properties of these phosphors were almost similar to PL properties when doped with individual Eu(3+), Tb(3+), and Dy(3+) ions, but were different when co-doped with Eu(3+)/Tb(3+) or Eu(3+)/Dy(3+) ions. In the case of Eu(3+)/Tb(3+) doped samples, the energy transfer process occurred unlike the PL channel. The calculated Commission International de l'Eclairage chromaticity coordinates of individual ion doped BG phosphors confirmed red, green, and white emissions and for co-doped samples they showed tunable emission.