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Molecules (Basel, Switzerland) Jan 2023In this article, we describe the antimicrobial properties of pristine anodised aluminium oxide matrices-the material many consider biologically inert. During a typical...
In this article, we describe the antimicrobial properties of pristine anodised aluminium oxide matrices-the material many consider biologically inert. During a typical anodisation process, chromium and chlorine compounds are used for electropolishing and the removal of the first-step aluminium oxide. Matrices without the use of those harmful compounds were also fabricated and tested for comparison. The antibacterial tests were conducted on four strains of : K12, R2, R3 and R4. The properties of the matrices were also compared to the three types of antibiotics: ciprofloxacin, bleomycin and cloxacillin using the Minimal Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. Moreover, DNA was isolated from the analysed bacteria which was additionally digested with formamidopyrimidine-DNA glycosylase (Fpg) protein from the group of repair glycosases. These enzymes are markers of modified oxidised bases in nucleic acids produced during oxidative stress in cells. Preliminary cellular studies, MIC and MBC tests and digestion with Fpg protein after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than the aforementioned antibiotics. The described composites are highly specific for the analysed model strains and may be used in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the progressing pandemic era. The results show much stronger antibacterial properties of the functionalised membranes on the action of bacterial membranes in comparison to the antibiotics in the Fpg digestion experiment. This is most likely due to the strong induction of oxidative stress in the cell through the breakdown of the analysed bacterial DNA.
Topics: DNA Repair; Escherichia coli Proteins; Aluminum; DNA, Bacterial; Oxides; DNA-Formamidopyrimidine Glycosylase; Escherichia coli; Anti-Bacterial Agents; Aluminum Oxide
PubMed: 36615599
DOI: 10.3390/molecules28010401 -
Clinical Oral Implants Research Sep 2023In patients with dental implants, what is the effect of transmucosal components made of materials other than titanium (alloys) compared to titanium (alloys) on the... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
In patients with dental implants, what is the effect of transmucosal components made of materials other than titanium (alloys) compared to titanium (alloys) on the surrounding peri-implant tissues after at least 1 year?
MATERIALS AND METHODS
This systematic review included eligible randomized controlled trials identified through an electronic search (Medline, Embase and Web of Science) comparing alternative abutment materials versus titanium (alloy) abutments with a minimum follow-up of 1 year and including at least 10 patients/group. Primary outcomes were peri-implant marginal bone level (MBL) and probing depth (PD), these were evaluated based on meta-analyses. Abutment survival, biological and technical complications and aesthetic outcomes were the secondary outcomes. The risk of bias was assessed with the RoB2-tool. This review is registered in PROSPERO with the number (CRD42022376487).
RESULTS
From 5129 titles, 580 abstracts were selected, and 111 full-text articles were screened. Finally, 12 articles could be included. Concerning the primary outcomes (MBL and PD), no differences could be seen between titanium abutment and zirconia or alumina abutments, not after 1 year (MBL: zirconia: MD = -0.24, 95% CI: -0.65 to 0.16, alumina: MD = -0.06, 95% CI: -0.29 to 0.17) (PD: zirconia: MD = -0.06, 95% CI: -0.41 to 0.30, alumina: MD = -0.29, 95% CI: -0.96 to 0.38), nor after 5 years. Additionally, no differences were found concerning the biological complications and aesthetic outcomes. The most important technical finding was abutment fracture in the ceramic group and chipping of the veneering material.
CONCLUSIONS
Biologically, titanium and zirconia abutments seem to function equally up to 5 years after placement.
Topics: Humans; Titanium; Dental Implants; Alloys; Aluminum Oxide
PubMed: 37750527
DOI: 10.1111/clr.14159 -
Molecules (Basel, Switzerland) Dec 2022Essential oils (EO) obtained from plants have proven industrial applications in the manufacturing of perfumes and cosmetics, in the production and flavoring of foods and... (Review)
Review
Essential oils (EO) obtained from plants have proven industrial applications in the manufacturing of perfumes and cosmetics, in the production and flavoring of foods and beverages, as therapeutic agents in aromatherapy, and as the active principles or excipients of medicines and pharmaceutics due to their olfactory, physical-chemical, and biological characteristics. On behalf of the new paradigm of a more natural and sustainable lifestyle, EO are rather appealing due to their physical, chemical, and physiological actions in human beings. However, EO are unstable and susceptible to degradation or loss. To tackle this aspect, the encapsulation of EO in microporous structures as zeolites is an attractive solution, since these host materials are cheap and non-toxic to biological environments. This overview provides basic information regarding essential oils, including their recognized benefits and functional properties. Current progress regarding EO encapsulation in zeolite structures is also discussed, highlighting some representative examples of essential oil delivery systems (EODS) based on zeolites for healthcare applications or aromatherapy.
Topics: Humans; Oils, Volatile; Zeolites; Microbial Sensitivity Tests
PubMed: 36500617
DOI: 10.3390/molecules27238525 -
International Journal of Environmental... Sep 2022The high salt-alkalinity of bauxite residue (BR) hinders plant growth and revegetation of bauxite residue disposal areas (BRDA), which cause serious potential...
The high salt-alkalinity of bauxite residue (BR) hinders plant growth and revegetation of bauxite residue disposal areas (BRDA), which cause serious potential environmental and ecological risks. Bioneutralization is a promising method for improving the properties of BR and plant colonization. In the present study, a strong saline-alkali tolerant bacteria (ZH-1) was isolated from aged BR and identified as sp. The medium of ZH-1 was optimized by orthogonal tests, and ZH-1 could decrease the medium pH from 11.8 to 6.01 (agitated culture) and 6.48 (static culture) by secretion of citric acid, oxalic acid and tartaric acid. With the inoculation of ZH-1, the pH of BR decreased from 11.6 to 8.76, and the water-soluble salt in BR increased by 68.11%. ZH-1 also changed the aggregate size distribution of BR, the mechanical-stable aggregates and water-stable aggregates increased by 18.76% and 10.83%, respectively. At the same time, the stability of the aggregates obviously increased and the destruction rate decreased from 94.37% to 73.46%. In addition, the microbial biomass carbon increased from 425 to 2794 mg/kg with the inoculation of ZH-1. Bacterial community analysis revealed that Clostridia, Bacilli, Gammaproteobacteria, Betaproteobacteria and Alphaproteobacteria were the main classes in the naturalized BR, and the inoculation of ZH-1 increased the diversity of bacteria in the BR. Overall, ZH-1 has great potential for neutralization and improvement the properties of BR and may be greatly beneficial for the revegetation of BRDA.
Topics: Alkalies; Aluminum Oxide; Bacteria; Carbon; Oxalic Acid; Plants; Soil; Water
PubMed: 36141868
DOI: 10.3390/ijerph191811590 -
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 -
Dental Materials Journal Apr 2022To compare full and partial coverage crowns made with different CAD/CAM leucite reinforced ceramic blocks on fracture resistance and fractographic analysis. Full...
To compare full and partial coverage crowns made with different CAD/CAM leucite reinforced ceramic blocks on fracture resistance and fractographic analysis. Full coverage and partial coverage crowns with finish line at 2 mm and 4 mm above the gingiva for molars made with IPS Empress CAD and Rosetta BM. After fatigue process, the fracture test and fractographic analysis were conducted. Although the fracture resistance of IPS Empress crowns did not show any statistical differences regardless of the design, both the partial coverage crowns fabricated using Rosetta BM showed significantly higher load at break and peak load than the full coverage crown. The crowns made with IPS Empress showed significantly higher fracture resistance than that made with Rosetta BM, regardless of the restorative design. The fracture resistance and fractographic analysis of CAD/CAM leucite reinforced full and partial coverage crowns were influenced by the restorative design of and material type.
Topics: Aluminum Silicates; Ceramics; Computer-Aided Design; Crowns; Dental Porcelain; Dental Prosthesis Design; Dental Restoration Failure; Dental Stress Analysis; Materials Testing
PubMed: 35095042
DOI: 10.4012/dmj.2021-253 -
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