-
Journal of Applied Toxicology : JAT Aug 2021Little is known about the uptake, biodistribution, and biological responses of nanoparticles (NPs) and their toxicity in developing animals. Here, male and female...
Biodistribution, cardiac and neurobehavioral assessments, and neurotransmitter quantification in juvenile rats following oral administration of aluminum oxide nanoparticles.
Little is known about the uptake, biodistribution, and biological responses of nanoparticles (NPs) and their toxicity in developing animals. Here, male and female juvenile Sprague-Dawley rats received four consecutive daily doses of 10 mg/kg Al O NP (diameter: 24 nm [transmission electron microscope], hydrodynamic diameter: 148 nm) or vehicle control (water) by gavage between postnatal days (PNDs) 17-20. Basic neurobehavioral and cardiac assessments were performed on PND 20. Animals were sacrificed on PND 21, and selected tissues were collected, weighed, and processed for histopathology or neurotransmitter analysis. The biodistribution of Al O NP in tissue sections of the intestine, liver, spleen, kidney, and lymph nodes were evaluated using enhanced dark-field microscopy (EDM) and hyperspectral imaging (HSI). Liver-to-body weight ratio was significantly increased for male pups administered Al O NP compared with control. HSI suggested that Al O NP was more abundant in the duodenum and ileum tissue of the female pups compared with the male pups, whereas the abundance of NP was similar for males and females in the other tissues. The abundance of NP was higher in the liver compared with spleen, lymph nodes, and kidney. Homovanillic acid and norepinephrine concentrations in brain were significantly decreased following Al O NP administration in female and male pups, whereas 5-hydroxyindoleacetic acid was significantly increased in male pups. EDM/HSI indicates intestinal uptake of Al O NP following oral administration. Al O NP altered neurotransmitter/metabolite concentrations in juvenile rats' brain tissues. Together, these data suggest that orally administered Al O NP interferes with the brain biochemistry in both female and male pups.
Topics: Administration, Oral; Aluminum Oxide; Animals; Brain; Electrocardiography; Female; Heart; Male; Metal Nanoparticles; Motor Activity; Neurotransmitter Agents; Rats; Rats, Sprague-Dawley; Rotarod Performance Test; Tissue Distribution
PubMed: 33269475
DOI: 10.1002/jat.4122 -
Molecules (Basel, Switzerland) May 2019The MgAlO-spinel has wide applications in various industries and in geosciences. It shows a significant inter-site Mg-Al cation exchange (denoted by the inversion... (Review)
Review
The MgAlO-spinel has wide applications in various industries and in geosciences. It shows a significant inter-site Mg-Al cation exchange (denoted by the inversion parameter ), which modifies structural features, such as the unit-cell parameters and the sizes of the component polyhedra, and influences the physical and chemical properties. Previous studies mainly focused on the kinetics and thermodynamics of the Mg-Al exchange reaction, with the aim to ascertain the correlation between the inversion parameter and temperature; these studies, however, reached conflicting results. Here, we first reviewed the kinetics studies on the Mg-Al cation exchange reaction, and then reviewed all thermodynamic experiments, with special attention paid to the Mg-Al cation exchange equilibrium and the quench process, which might have modified the cation distributions once attained at high temperatures. We also assessed the accuracies in the temperature measurements and in the quantifications of the by different analytical methods. With some necessary temperature correction and data removal, we have landed with a generally reliable - dataset covering the - space of 873 < < 1887 K and 0.18(1) < < 0.357(60) (71 data pairs in total). Fitting these - data to three most commonly used thermodynamic models, we have obtained more accurate model parameters. Further, we also evaluated the constituent items of the Gibbs free energy for the Mg-Al cation exchange reaction with experimental results from different research fields and reached the conclusion that highly possibly the T Δ S D should not be neglected. Based on this review, we suggest that: (1) Further kinetics study on the Mg-Al exchange reaction should be performed at both low (<~973 K) and high (>~1173 K); (2) further Mg-Al exchange equilibrium studies should be carried out at relatively low and ambient , as well as in vast ranges of simultaneous high and high ; and (3) direct experimental measures about the entropies or the enthalpies of the MgAlO-spinels disordered to different extents should be conducted with full characterization of the starting materials and detailed description of the experimental procedures.
Topics: Aluminum Oxide; Entropy; Hydrogen-Ion Concentration; Kinetics; Magnesium Oxide; Molecular Structure; Thermodynamics
PubMed: 31052437
DOI: 10.3390/molecules24091704 -
Molecules (Basel, Switzerland) Sep 2019A novel tweakable nanocomposite was prepared by spark plasma sintering followed by systematic oxidation of carbon nanotube (CNT) molecules to produce alumina/carbon...
A novel tweakable nanocomposite was prepared by spark plasma sintering followed by systematic oxidation of carbon nanotube (CNT) molecules to produce alumina/carbon nanotube nanocomposites with surface porosities. The mechanical properties (flexural strength and fracture toughness), surface area, and electrical conductivities were characterized and compared. The nanocomposites were extensively analyzed by field emission scanning electron microscopy (FE-SEM) for 2D qualitative surface morphological analysis. Adding CNTs in ceramic matrices and then systematically oxidizing them, without substantial reduction in densification, induces significant capability to achieve desirable/application oriented balance between mechanical, electrical, and catalytic properties of these ceramic nanocomposites. This novel strategy, upon further development, opens new level of opportunities for real-world/industrial applications of these relatively novel engineering materials.
Topics: Aluminum Oxide; Ceramics; Electric Conductivity; Nanocomposites; Nanotubes, Carbon
PubMed: 31480573
DOI: 10.3390/molecules24173176 -
Journal of Immunological Methods Jul 2015The mechanism behind the adjuvant effect of aluminum salts is poorly understood notwithstanding that aluminum salts have been used for decades in clinical vaccines. In...
The mechanism behind the adjuvant effect of aluminum salts is poorly understood notwithstanding that aluminum salts have been used for decades in clinical vaccines. In an aqueous environment and at a nearly neutral pH, the aluminum salts form particulate aggregates, and one plausible explanation of the lack of information regarding the mechanisms could be the absence of an efficient method of tracking phagocytosed aluminum adjuvants and thereby the intracellular location of the adjuvant. In this paper, we want to report upon the use of lumogallion staining enabling the detection of phagocytosed aluminum adjuvants inside viable cells. Including micromolar concentrations of lumogallion in the culture medium resulted in a strong fluorescence signal from cells that had phagocytosed the aluminum adjuvant. The fluorescence appeared as spots in the cytoplasm and by confocal microscopy and co-staining with probes presenting fluorescence in the far-red region of the spectrum, aluminum adjuvants could to a certain extent be identified as localized in acidic vesicles, i.e., lysosomes. Staining and detection of intracellular aluminum adjuvants was achieved not only by diffusion of lumogallion into the cytoplasm, thereby highlighting the presence of the adjuvant, but also by pre-staining the aluminum adjuvant prior to incubation with cells. Pre-staining of aluminum adjuvants resulted in bright fluorescent particulate aggregates that remained fluorescent for weeks and with only a minor reduction of fluorescence upon extensive washing or incubation with cells. Both aluminum oxyhydroxide and aluminum hydroxyphosphate, two of the most commonly used aluminum adjuvants in clinical vaccines, could be pre-stained with lumogallion and were easily tracked intracellularly after incubation with phagocytosing cells. Staining of viable cells using lumogallion will be a useful method in investigations of the mechanisms behind aluminum adjuvants' differentiation of antigen-presenting cells into inflammatory cells. Information will be gained regarding the phagosomal pathways and the events inside the phagosomes, and thereby the ultimate fate of phagocytosed aluminum adjuvants could be resolved.
Topics: Adjuvants, Immunologic; Aluminum Hydroxide; Aluminum Oxide; Animals; Benzenesulfonates; Cell Line, Tumor; Flavonoids; Fluorescent Dyes; Humans; Mice; Mice, Inbred C57BL; Microscopy, Confocal; Phagocytosis; Phosphates; Staining and Labeling
PubMed: 25896212
DOI: 10.1016/j.jim.2015.04.008 -
Bond durability and surface states of titanium, Ti-6Al-4V alloy, and zirconia for implant materials.Journal of Prosthodontic Research Apr 2022Screw-retained implant crowns used as dental implants comprise a zirconia coping and titanium base bonded using resin cement. These devices are prone to debonding...
PURPOSE
Screw-retained implant crowns used as dental implants comprise a zirconia coping and titanium base bonded using resin cement. These devices are prone to debonding failures. This study investigated the bond characteristics of implant materials based on shear bond strength (SBS) and surface characteristics.
METHODS
Chemically pure (CP) titanium grade-4 (Ti), Ti-6Al-4V alloy (Ti-6Al-4V), and tetragonal polycrystalline zirconia (zirconia) were evaluated as adherent materials. Plates of each material were polished, primed for the respective resin cements, and cemented using either methyl methacrylate-based resin cement (Super-Bond) or composite-based resin cement (Panavia). The cemented samples were subjected to 10,000 thermocycles alternating between 5 and 55 °C, and the SBS were obtained before and after thermocycling. The sample surfaces were characterized based on surface observations, roughness, and free energy (SFE).
RESULTS
The SBSs of all materials bonded using Panavia were significantly compromised during thermocycling and reached zero. Although the SBSs of Ti and Ti-6Al-4V bonded using Super-Bond were not significantly affected by thermocycling, those of zirconia decreased significantly. The bond durability between zirconia and Super-Bond was improved via alumina air-abrasion, which caused no significant loss of SBS after thermocycling. Surface analyses of the air-abraded zirconia validated these results and confirmed that its surface roughness and SFE were significantly increased.
CONCLUSION
The bond durability between resin cement and zirconia was lower than that between Ti and Ti-6Al-4V. The alumina air-abrasion pretreatment of zirconia improved the SFE and surface roughness, thereby enhancing bond durability.
Topics: Alloys; Aluminum Oxide; Dental Bonding; Dental Materials; Materials Testing; Resin Cements; Shear Strength; Surface Properties; Titanium; Zirconium
PubMed: 34470984
DOI: 10.2186/jpr.JPR_D_20_00297 -
Scientific Reports Oct 2022Magnetic nanomaterials are increasingly impacting the field of biology and medicine. Their versatility in terms of shape, structure, composition, coating, and magnetic...
Magnetic nanomaterials are increasingly impacting the field of biology and medicine. Their versatility in terms of shape, structure, composition, coating, and magnetic responsivity make them attractive for drug delivery, cell targeting and imaging. Adipose derived-mesenchymal cells (ASCs) are intensely scrutinized for tissue engineering and regenerative medicine. However, differentiation into musculoskeletal lineages can be challenging. In this paper, we show that uncoated nickel nanowires (Ni NW) partially released from their alumina membrane offer a mechanically-responsive substrate with regular topography that can be used for the delivery of magneto-mechanical stimulation. We have used a tailored protocol for improving ASCs adherence to the substrate, and showed that cells retain their characteristic fibroblastic appearance, cytoskeletal fiber distribution and good viability. We report here for the first time significant increase in osteogenic but not adipogenic differentiation of ASCs on Ni NW exposed to 4 mT magnetic field compared to non-exposed. Moreover, magnetic actuation is shown to induce ASCs osteogenesis but not adipogenesis in the absence of external biochemical cues. While these findings need to be verified in vivo, the use of Ni NW substrate for inducing osteogenesis in the absence of specific differentiation factors is attractive for bone engineering. Implant coating with similar surfaces for orthopedic and dentistry could be as well envisaged as a modality to improve osteointegration.
Topics: Adipose Tissue; Aluminum Oxide; Cell Differentiation; Cells, Cultured; Magnetic Phenomena; Nanowires; Nickel; Osteogenesis
PubMed: 36202902
DOI: 10.1038/s41598-022-21145-z -
Analytical and Bioanalytical Chemistry Jan 2021Hybrid material surfaces on microparticles are emerging as vehicles for many biomedical multiplexing applications. Functionalization of these hybrid surface...
Hybrid material surfaces on microparticles are emerging as vehicles for many biomedical multiplexing applications. Functionalization of these hybrid surface microparticles to biomolecules presents unique challenges related to optimization of surface chemistries including uniformity, repeatability, and sample sparring. Hybrid interfaces between microlevel surfaces and individual biomolecules will provide different microenvironments impacting the surface functionalization optimization and efficiency. Here, we propose and validate the first demonstration of streptavidin adsorption-based antibody functionalization on unmodified, hybrid surface microparticles for in vitro analysis. We test this analytical technique and fabricate hybrid surface microparticles with a polystyrene core and aluminum oxide semi-coating. Additionally, we optimize the streptavidin-biotin functionalization chemistry in both assay implementation and sample sparring via analytical mass balances for these microparticles and subsequently conjugate anti-human CD11b antibodies. Result confirmation and characterization occurs from ultraviolet protein absorbance and ImageJ processing of fluorescence microscopy images. Additionally, we design and implement the multi-sectional imaging (MSI) approach to support functionalization uniformity on the hybrid surface microparticles. Finally, as a proof-of-concept performance, we validate anti-CD11b antibodies functionalization by visualizing hybrid surface microparticles conjugate to human neutrophils isolated from blood samples collected from potentially septic patients. Our study introduces and defines a category of functionalization for hybrid surface microparticles with the intent of minuscule sample volumes, low cost, and low environmental impact to be used for many cellular or proteomic in vitro multiplexing applications in the future. Graphical abstract.
Topics: Adsorption; Aluminum Oxide; Biotin; CD11b Antigen; Humans; In Vitro Techniques; Microscopy, Fluorescence; Microspheres; Neutrophils; Particle Size; Polystyrenes; Streptavidin; Surface Properties
PubMed: 33156401
DOI: 10.1007/s00216-020-03026-4 -
Biosensors Sep 2022Sensitivity is one of the crucial factors in determining the quality of a fluorescence/phosphorescence-based gas sensor, and is estimated from the measurement of...
Sensitivity is one of the crucial factors in determining the quality of a fluorescence/phosphorescence-based gas sensor, and is estimated from the measurement of responses (I/I, where I and I refer to the measured optical intensity of a sensor in absence and presence of analyte molecules) at various concentrations of analytes. In this work, we demonstrate phosphorescence-based optical oxygen sensors fabricated on highly porous anodic aluminum oxide (AAO) membranes showing dramatically high response. These sensors exploit the enormous surface area of the AAO to facilitate the effective interaction between the sensing molecules and the analytes. We spin-coat an AAO membrane (200 nm pore diameter) with a platinum-based oxygen sensing porphyrin dye, platinum(II) meso-tetrakis (pentafluorophenyl) porphyrin (PtTFPP), to fabricate a sensor exhibiting I/I ~400 at 100% oxygen atmosphere. To address the generality of the AAO membrane, we fabricate a separate sensor with another porphyrin dye, platinum octaethylporphyrin (PtOEP), which exhibits an even higher I/I of ~500. Both of these sensors offer the highest responses as an optical oxygen sensor hitherto reported. SEM and EDS analysis are performed to realize the effect of the increased surface area of the AAO membrane on the enhanced sensitivity.
Topics: Porphyrins; Platinum; Oxygen; Porosity; Aluminum Oxide
PubMed: 36290912
DOI: 10.3390/bios12100774 -
Molecules (Basel, Switzerland) Apr 2022The development of green and sustainable materials for use as heterogeneous catalysts is a growing area of research in chemistry. In this paper, mesoporous SiO-AlO mixed...
The development of green and sustainable materials for use as heterogeneous catalysts is a growing area of research in chemistry. In this paper, mesoporous SiO-AlO mixed oxide catalysts with different Si/Al ratios were prepared via hydrolytic (HSG) and nonhydrolytic sol-gel (NHSG) processes. The HSG route was explored in acidic and basic media, while NHSG was investigated in the presence of diisopropylether as an oxygen donor. The obtained materials were characterized using EDX, N-physisorption, powder XRD, Si, Al MAS-NMR, and NH-TPD. This approach offered good control of composition and the Si/Al ratio was found to influence both the texture and the acidity of the mesoporous materials. According to Al and Si MAS NMR analyses, silicon and aluminum were more regularly distributed in NHSG samples that were also more acidic. Silica-alumina catalysts prepared via NHSG were more active in esterification of acetic acid with n-BuOH.
Topics: Aluminum Oxide; Catalysis; Esterification; Gels; Oxides; Silicon Dioxide
PubMed: 35458732
DOI: 10.3390/molecules27082534 -
Asian Pacific Journal of Cancer... Nov 2023Grape hybrids are characterized by different chemical compositions; often with high hybrids are characterized by different chemical compositions, often with a high...
Antiproliferative and Apoptosis Effects of Hybrid Varieties of Vitis vinifera L. Sweet Sapphire and Sweet Surprise on Human Prostate Cancer Cells Using In Vitro and In Silico Approaches.
OBJECTIVE
Grape hybrids are characterized by different chemical compositions; often with high hybrids are characterized by different chemical compositions, often with a high phenolic content and a specific profile of anthocyanins. The aim of study was to characterize the constituents of hybrid Vitis vinifera L. varieties Sweet Sapphire (SA) and Sweet Surprise (SU) extracts and their influence on apoptosis induction and antiproliferative effects on human prostate cancer cells.
METHODS
We used the MTT assay to evaluate the cytotoxic effect of extracts of SA and SU, on the prostate adenocarcinoma cell lines PC-3 and DU-145. To analyze the inhibiting impact by flow cytometry, used 24 and 48 hours. Anthocyanins were quantified by liquid chromatography and analysed by their absorption rate, hepatotoxicity, blood concentration, blood-brain barrier passage ability and maximum recommended dose by in silico approaches.
RESULTS
Our results showed that malvidin derivatives present the highest content in both cultivars. We identified 14.46mg/100g malvidin-3-O-glycoside in SA and 2.76 mg/100 g in SU. A reduction in cell viability of DU-145 (45 and 65%) and PC-3 (63 and 67%) cells after 48h treatment with SA and SU, respectively, was found via MTT assay. Flow cytometry showed that the treatment with extracts from SA and SU had an inhibitory impact on cell development due to G2/M arrest and caused a rise in apoptotic cells compared to control group. None of the anthocyanin presented hepatotoxicity as well as blood-brain barrier passage ability. Peonidin 3-O-glucoside had the lower maximum recommended dose as well as the highest intestinal absorption rate. However, delphinidin 3-O-glucoside had the highest blood concentration values.
CONCLUSION
The findings of this study highlight the potential of hybrid Vitis vinifera L. varieties as an important source of natural antioxidants and their protective effect against prostate cancer cells as well as elucidate in part their anthocyanin's metabolism.
Topics: Male; Humans; Apoptosis; Anthocyanins; Vitis; Cell Line, Tumor; G2 Phase Cell Cycle Checkpoints; Prostatic Neoplasms; Aluminum Oxide; Glucosides; Chemical and Drug Induced Liver Injury
PubMed: 38019224
DOI: 10.31557/APJCP.2023.24.11.3673