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Applied Microbiology and Biotechnology Sep 2022In the present work, the approaches of submerged co-cultivation and microparticle-enhanced cultivation (MPEC) were combined and evaluated over the course of three case...
In the present work, the approaches of submerged co-cultivation and microparticle-enhanced cultivation (MPEC) were combined and evaluated over the course of three case studies. The filamentous fungus Aspergillus terreus was co-cultivated with Penicillium rubens, Streptomyces rimosus, or Cerrena unicolor in shake flasks with or without the addition of aluminum oxide microparticles. The influence of microparticles on the production of lovastatin, penicillin G, oxytetracycline, and laccase in co-cultures was compared with the effects recorded for the corresponding monocultures. In addition, the quantitative analyses of morphological parameters, sugars consumption, and by-products formation were performed. The study demonstrated that the influence of microparticles on the production of a given molecule in mono- and co-culture may differ considerably, e.g., the biosynthesis of oxytetracycline was shown to be inhibited due to the presence of aluminum oxide in "A. terreus vs. S. rimosus" co-cultivation variants but not in S. rimosus monocultures. The differences were also observed regarding the morphological characteristics, e.g., the microparticles-induced changes of projected area in the co-cultures and the corresponding monocultures were not always comparable. In addition, the study showed the importance of medium composition on the outcomes of MPEC, as exemplified by lovastatin production in A. terreus monocultures. Finally, the co-cultures of A. terreus with a white-rot fungus C. unicolor were described here for the first time. KEY POINTS: • Aluminum oxide affects secondary metabolites production in submerged co-cultures. • Mono- and co-cultures are differently impacted by the addition of aluminum oxide. • Effect of aluminum oxide on metabolites production depends on medium composition.
Topics: Aluminum Oxide; Basidiomycota; Coculture Techniques; Lovastatin; Oxytetracycline
PubMed: 35906994
DOI: 10.1007/s00253-022-12087-7 -
Sensors (Basel, Switzerland) Jun 2023During the secondary production of aluminum, upon melting the scrap in a furnace, there is the possibility of developing an aluminothermic reaction, which produces...
During the secondary production of aluminum, upon melting the scrap in a furnace, there is the possibility of developing an aluminothermic reaction, which produces oxides in the molten metal bath. Aluminum oxides must be identified and removed from the bath, as they modify the chemical composition and reduce the purity of the product. Furthermore, accurate measurement of molten aluminum level in a casting furnace is crucial to obtain an optimal liquid metal flow rate which influences the final product quality and process efficiency. This paper proposes methods for the identification of aluminothermic reactions and molten aluminum levels in aluminum furnaces. An RGB Camera was used to acquire video from the furnace interior, and computer vision algorithms were developed to identify the aluminothermic reaction and melt level. The algorithms were developed to process the image frames of video acquired from the furnace. Results showed that the proposed system allowed the online identification of the aluminothermic reaction and the molten aluminum level present inside the furnace at a computation time of 0.7 s and 0.4 s per frame, respectively. The advantages and limitations of the different algorithms are presented and discussed.
Topics: Aluminum; Aluminum Oxide; Oxides
PubMed: 37420673
DOI: 10.3390/s23125506 -
Arhiv Za Higijenu Rada I Toksikologiju Dec 2021The aim of this study was to evaluate the genotoxic effects of AlO, FeO, and Cu nanoparticles with chromosomal aberration (CA), micronucleus (MN), and comet assays on...
The aim of this study was to evaluate the genotoxic effects of AlO, FeO, and Cu nanoparticles with chromosomal aberration (CA), micronucleus (MN), and comet assays on the bone marrow of male BALB/c mice. Three doses of AlO, FeO (75, 150, and 300 mg/kg), or Cu (5, 10, and 15 mg/kg) nanoparticles were administered to mice through intraperitoneal injection once a day for 14 days and compared with negative control (distilled water) and positive control (mitomycin C and methyl methanesulphonate). AlO and FeO did not show genotoxic effects, but Cu nanoparticles induced significant (P<0.05) genotoxicity at the highest concentration compared to negative control. Our findings add to the health risk information of AlO, FeO, and Cu nanoparticles regarding human exposure (occupational and/or through consumer products or medical treatment), and may provide regulatory reference for safe use of these nanoparticles. However, before they can be used safely and released into the environment further chronic studies are essential.
Topics: Aluminum Oxide; Animals; Bone Marrow Cells; Chromosome Aberrations; Comet Assay; Copper; DNA Damage; Ferric Compounds; Male; Metal Nanoparticles; Mice; Micronucleus Tests
PubMed: 34985838
DOI: 10.2478/aiht-2021-72-3578 -
Journal of Orthopaedic Surgery and... Jul 2020Reconstruction of metaphyseal fractures represents a clinical challenge for orthopedic surgeons. Especially in osteoporotic bone, these fractures are frequently...
BACKGROUND
Reconstruction of metaphyseal fractures represents a clinical challenge for orthopedic surgeons. Especially in osteoporotic bone, these fractures are frequently accompanied by osseous substance defects. In order to ensure rapid mobilization of patients, high stability requirements must be met by osteosynthesis. Various bone graft materials have been introduced in the past, such as autologous bone or exogenous bone substitute materials. These are used as bone void fillers or as augmentation techniques to ensure safe fixation of osteosynthesis. New calcium phosphate-based bone void-filling materials could be a promising alternative to autologous bone or to the currently and widely used polymethylmethacrylate (PMMA)-based cement. The aim of this study was to evaluate a novel paste-like bone void filler in vivo and in vitro with regard to biocompatibility and osteoconductivity.
METHODS
In addition to in vitro testing of cell compatibility using pre-osteoblasts (MC3T3-E1), 35 Wistar rats were treated in vivo with implantation of various material mixtures based on calcium phosphate and aluminum oxide reinforcement in a metaphyseal drill hole defect. After 4 weeks, an examination by micro-computed tomography (μCT) and histology was performed.
RESULTS
The in vitro analysis showed good biocompatibility with a high cell survival of osteoblasts. In the in vivo experiments, a significantly higher bone ingrowth compared to the empty defect was shown by μCT and histological analysis. Here, the group receiving material reinforced with aluminum oxide (AlO) showed a bone volume/tissue volume (BV/TV) of 89.19% compared to a BV/TV of 83.14% for the empty defect (p = 0.0013). In the group treated with a polysaccharide matrix, no increase in BV/TV was observed given a mean ratio of 80.14%. Scoring of histological sections did not reveal a significant difference between CaP and CaP that was substituted with AlO.
CONCLUSION
The results of this study show an encouraging first step towards the development of new pasty, bone void-filling materials. We demonstrated that a new paste-like bone-filling material, based on calcium phosphate granulates and aluminum oxide to provide strength, exhibits good biocompatibility and osteoconductivity. Further biomechanical test in an osteoporotic animal model will have to be performed, to prove feasibility in metaphyseal defects.
Topics: Aluminum Oxide; Animals; Biocompatible Materials; Bone Regeneration; Bone Substitutes; Calcium Phosphates; Disease Models, Animal; Epiphyses; Fractures, Bone; Orthopedic Procedures; Osteoblasts; Osteoporosis; Rats, Wistar; Plastic Surgery Procedures
PubMed: 32727506
DOI: 10.1186/s13018-020-01801-8 -
Environmental Science and Pollution... Jun 2022The aim of this work is study of physical and chemical properties of dust of the Pre-Aral region of Uzbekistan such as Karakalpakstan and Khorezm that are located near...
The aim of this work is study of physical and chemical properties of dust of the Pre-Aral region of Uzbekistan such as Karakalpakstan and Khorezm that are located near the three deserts such as the Aralkum, Karakum, and Kyzylkum. The dust particles fell on glass have been collected in Karakalpakstan and Khorezm and studied systematically by employing wide range of methods. Particle volume vs size distribution has been measured with maximum around 600 nm and ~ 10 µm. The major and minor constituent materials present in the dust have been studied systematically by X-ray fluorescence spectroscopy, energy dispersive X-ray diffraction, and inductively coupled plasma optical emission spectroscopy. Main characteristic absorption bands corresponding to Si-O, Si-O-Si bonding in quartz and Fe-O bonds in hematite FeO have been identified by infrared and Raman spectroscopy. Quartz, hematite, lime, corundum, magnesia, and several other trace minerals have been identified in the dust particles. X-ray diffraction peaks corresponding to quartz, hematite, and corundum are sharp and are found to be more crystalline with some level of disorder. Analysis of the particle size and crystallinity on human being has been performed: disordered or crystalline quartz can create the lung disease; the particles in the size of 0.5-0.7 µm may produce diseases such as chronic silicosis, silicosis, and silica tuberculosis whereas hematite might create lung disease. Dust particles worsen optical transmittance of glass of the panels.
Topics: Aluminum Oxide; Dust; Humans; Particle Size; Quartz; Silicosis; Uzbekistan
PubMed: 35084677
DOI: 10.1007/s11356-022-18827-6 -
International Journal of Molecular... Jan 2023Agglomeration of distributed particles is the main problem in polymer composites reinforced with such particles. It leads to a decrease in mechanical performance and its...
Agglomeration of distributed particles is the main problem in polymer composites reinforced with such particles. It leads to a decrease in mechanical performance and its poor reproducibility. Thus, development of methods to address the agglomeration of particles is relevant. Evaluation of the size and concentration of agglomerates is required to select a method to address agglomeration. The paper analyzes aluminum oxide particles agglomeration in particles-reinforced polymethyl methacrylate (PMMA) composites. Quantitative parameters of polystyrene-coated aluminum oxide particles agglomerates are obtained for the first time in this article. Unlike uncoated aluminum oxide particles, when coated aluminum oxide particles are used, agglomerates concentration in polymer composites decreases approx. 10 times. It demonstrates that modification of submicron particles by a polymer coating decreases the number of agglomerates in the polymer composite. The use of transmittance and opacity values to estimate particles agglomerates is reasonable in this article. It is shown that the difference in optical performance of specimens reinforced with coated and the original particles is related to the number and average size of agglomerates in the specimens. For example, when the concentration exceeds 0.2%, transmittance values for the specimens reinforced with coated particles are greater than the ones for the specimens reinforced with the original particles.
Topics: Polymethyl Methacrylate; Aluminum; Aluminum Oxide; Reproducibility of Results; Polymers
PubMed: 36768833
DOI: 10.3390/ijms24032515 -
Journal of Biomedical Optics Sep 2021The highest absorption peaks of the main components of bone are in the mid-infrared region, making Er:YAG and CO2 lasers the most efficient lasers for cutting bone. Yet,...
SIGNIFICANCE
The highest absorption peaks of the main components of bone are in the mid-infrared region, making Er:YAG and CO2 lasers the most efficient lasers for cutting bone. Yet, studies of deep bone ablation in minimally invasive settings are very limited, as finding suitable materials for coupling high-power laser light with low attenuation beyond 2 μm is not trivial.
AIM
The first aim of this study was to compare the performance of different optical fibers in terms of transmitting Er:YAG laser light with a 2.94-μm wavelength at high pulse energy close to 1 J. The second aim was to achieve deep bone ablation using the best-performing fiber, as determined by our experiments.
APPROACH
In our study, various optical fibers with low attenuation (λ = 2.94 μm) were used to couple the Er:YAG laser. The fibers were made of germanium oxide, sapphire, zirconium fluoride, and hollow-core silica, respectively. We compared the fibers in terms of transmission efficiency, resistance to high Er:YAG laser energy, and bending flexibility. The best-performing fiber was used to achieve deep bone ablation in a minimally invasive setting. To do this, we adapted the optimal settings for free-space deep bone ablation with an Er:YAG laser found in a previous study.
RESULTS
Three of the fibers endured energy per pulse as high as 820 mJ at a repetition rate of 10 Hz. The best-performing fiber, made of germanium oxide, provided higher transmission efficiency and greater bending flexibility than the other fibers. With an output energy of 370 mJ per pulse at 10 Hz repetition rate, we reached a cutting depth of 6.82 ± 0.99 mm in sheep bone. Histology image analysis was performed on the bone tissue adjacent to the laser ablation crater; the images did not show any structural damage.
CONCLUSIONS
The findings suggest that our prototype could be used in future generations of endoscopic devices for minimally invasive laserosteotomy.
Topics: Aluminum Oxide; Animals; Endoscopes; Laser Therapy; Lasers, Solid-State; Optical Fibers; Sheep
PubMed: 34519191
DOI: 10.1117/1.JBO.26.9.095002 -
Vaccine Oct 2022The rapid spread of COVID-19 on all continents and the mortality induced by SARS-CoV-2 virus, the cause of the pandemic coronavirus disease 2019 (COVID-19) has motivated...
The rapid spread of COVID-19 on all continents and the mortality induced by SARS-CoV-2 virus, the cause of the pandemic coronavirus disease 2019 (COVID-19) has motivated an unprecedented effort for vaccine development. Inactivated viruses as well as vaccines focused on the partial or total sequence of the Spike protein using different novel platforms such us RNA, DNA, proteins, and non-replicating viral vectors have been developed. The high global need for vaccines, now and in the future, and the emergence of new variants of concern still requires development of accessible vaccines that can be adapted according to the most prevalent variants in the respective regions. Here, we describe the immunogenic properties of a group of theoretically predicted RBD peptides to be used as the first step towards the development of an effective, safe and low-cost epitope-focused vaccine. One of the tested peptides named P5, proved to be safe and immunogenic. Subcutaneous administration of the peptide, formulated with alumina, induced high levels of specific IgG antibodies in mice and hamsters, as well as an increase of IFN-γ expression by CD8+ T cells in C57 and BALB/c mice upon in vitro stimulation with P5. Neutralizing titers of anti-P5 antibodies, however, were disappointingly low, a deficiency that we will attempt to resolve by the inclusion of additional immunogenic epitopes to P5. The safety and immunogenicity data reported in this study support the use of this peptide as a starting point for the design of an epitope restricted vaccine.
Topics: Cricetinae; Humans; Mice; Animals; SARS-CoV-2; Epitopes; Spike Glycoprotein, Coronavirus; COVID-19 Vaccines; COVID-19; Viral Vaccines; Antibodies, Viral; Immunoglobulin G; Peptides; RNA; Aluminum Oxide; Antibodies, Neutralizing
PubMed: 36195474
DOI: 10.1016/j.vaccine.2022.09.059 -
Bioprocess and Biosystems Engineering Jan 2022Immobilizing microorganisms inside 3D printed semi-permeable substrates can be desirable for biotechnological processes since it simplifies product separation and...
Immobilizing microorganisms inside 3D printed semi-permeable substrates can be desirable for biotechnological processes since it simplifies product separation and purification, reducing costs, and processing time. To this end, we developed a strategy for synthesizing a feedstock suitable for 3D bioprinting of mechanically rigid and insoluble materials with embedded living bacteria. The processing route is based on a highly particle-filled alumina/chitosan nanocomposite gel which is reinforced by (a) electrostatic interactions with alginate and (b) covalent binding between the chitosan molecules with the mild gelation agent genipin. To analyze network formation and material properties, we characterized the rheological properties and printability of the feedstock gel. Stability measurements showed that the genipin-crosslinked chitosan/alginate/alumina gels did not dissolve in PBS, NaOH, or HCl after 60 days of incubation. Alginate-containing gels also showed less swelling in water than gels without alginate. Furthermore, E. coli bacteria were embedded in the nanocomposites and we analyzed the influence of the individual bioink components as well as of the printing process on bacterial viability. Here, the addition of alginate was necessary to maintain the effective viability of the embedded bacteria, while samples without alginate showed no bacterial viability. The experimental results demonstrate the potential of this approach for producing macroscopic bioactive materials with complex 3D geometries as a platform for novel applications in bioprocessing.
Topics: Alginates; Aluminum Oxide; Chitosan; Gels; Iridoids; Nanocomposites; Printing, Three-Dimensional
PubMed: 34664115
DOI: 10.1007/s00449-021-02650-3 -
Naunyn-Schmiedeberg's Archives of... Apr 2023The present study was designed to evaluate the probable ameliorative role of quercetin (QCN) against oxidative hepatotoxicity induced by aluminum oxide nanoparticles...
The present study was designed to evaluate the probable ameliorative role of quercetin (QCN) against oxidative hepatotoxicity induced by aluminum oxide nanoparticles (AlONPs) with a diameter < 30 nm and lead acetate (Pb) co-exposure in adult male Sprague-Dawley rats. Rats were weighed and allocated to seven groups (n = 10 each) and were treated orally via orogastric gavage for 60 successive days: rats of the 1st group were kept as control given distilled water (1 ml/kg), rats of the 2nd group received 2 ml/kg BW/day corn oil; rats of the 3rd group were administered 20 mg/kg BW QCN/day; rats of the 4th group received 100 mg/kg BW AlONPs; rats of the 5th group received 50 mg/kg BW Pb; rats of the 6th group co-received AlONPs and Pb at the same previous doses; and rats of the 7th group were co-administered AlONPs, Pb, and QCN at the same previous doses. At the end of the experiment, serum levels of alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total, direct, indirect bilirubin, triglycerides, total cholesterol, HDL, VLDL, and LDL were estimated. The hepatic oxidative stress biomarkers as superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GPx), were also evaluated. Finally, the histopathological and histomorphometric evaluations and the residues of Al and Pb in hepatic tissues were assessed. AlONPs and/or Pb exposure significantly elevated lipid peroxidation levels and considerably altered the hepatic biochemical parameters; nevertheless, QCN significantly reduced hepatic enzymes compared to toxicant exposed groups. Additionally, QCN significantly improved AlONPs-afforded liver tissue damage, as established in microscopic findings on the liver in the group treated with AlONPs + Pb. Conclusively, QCN could be a candidate natural agent to safeguard the liver versus the co-harmful impacts of AlONPs and Pb toxicity.
Topics: Rats; Male; Animals; Quercetin; Rats, Sprague-Dawley; Aluminum Oxide; Lead; Antioxidants; Liver; Oxidative Stress; Hepatitis; Nanoparticles; Acetates; Chemical and Drug Induced Liver Injury
PubMed: 36472630
DOI: 10.1007/s00210-022-02351-y