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Nudibranchs, with their mesmerizing diversity and ecological significance, play crucial roles in marine ecosystems. Central to their feeding prowess is the radula, a chitinous structure with diverse morphologies adapted to prey preferences and feeding strategies. This study focuses on elucidating wear coping mechanisms in radular teeth of carnivorous molluscs, employing Dendronotus lacteus (Dendronotidae) and Flabellina affinis (Flabellinidae) as model species. Both species forage on hydrozoans. Through scanning electron microscopy, confocal laser scanning microscopy, nanoindentation, and energy-dispersive X-ray spectroscopy, the biomechanical and compositional properties of their teeth were analyzed. Notably, tooth coatings, composed of calcium (Ca) or silicon (Si) and high hardness and stiffness compared to the internal tooth structure, with varying mineral contents across tooth regions and ontogenetic zones, were found. The presence of the hard and stiff tooth coatings highlight their role in enhancing wear resistance. The heterogeneities in the autofluorescence patterns related to the distribution of Ca and Si of the coatings. Overall, this study provides into the biomechanical adaptations of nudibranch radular teeth, shedding light on the intricate interplay between tooth structure, elemental composition, and ecological function in marine molluscs.
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Gastrópodos , Diente , Animales , Gastrópodos/anatomía & histología , Gastrópodos/fisiología , Diente/anatomía & histología , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Fenómenos BiomecánicosRESUMEN
Portable X-ray Fluorescence probe (pXRF) is a tool used to measure many elements quickly and efficiently in soil with minimal sample preparation. Although this sensing technique has been widely used to determine total elemental concentrations, it has not been calibrated for plant-available nutrient predictions. We evaluated the potential of using pXRF for fast plant-available nutrient quantification. Two experiments were conducted in soils treated with two types of biochars to obtain a practical range of soil pH (5.5 - 8.0) and organic carbon (2.0 - 5.5%). Biochars applied were derived from switchgrass (SGB) and poultry litter (PLB). The first experiment received biochars at application rates up to 8% (w/w) and had no plants. The second experiment had up to 4% of SGB or PLB planted with ryegrass (Lolium perenne). Linear regression (LR), polynomial regression (PolR), power regression (PowR), and stepwise multiple linear regression (SMLR) were the models tested. Regardless of the extraction method, phosphorus (P) showed a strong relationship between pXRF and several laboratory extraction methods; however, K prediction via pXRF was sensitive to the plant factor. The optimum soil available-P corresponding to the maximum P uptake in plant tissues can be assessed with pXRF. The LR was inconsistent for calcium (Ca), sulfur (S), and copper (Cu) and non-significant for magnesium (Mg), iron (Fe), and zinc (Zn). Our results showed that pXRF is applicable to estimate P availability in soils receiving organic amendments. More evaluations are needed with diverse soil types to confirm the findings before using pXRF for fertilizer recommendation.
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Carbón Orgánico , Suelo , Espectrometría por Rayos X , Suelo/química , Carbón Orgánico/química , Espectrometría por Rayos X/métodos , Nutrientes/análisis , Fósforo/análisis , Lolium/química , Lolium/metabolismo , Plantas/química , Plantas/metabolismoRESUMEN
Identifying evidence of human modification of extinct animal remains, such as Pleistocene megafauna, is challenging due to the similarity of anthropogenic and non-anthropogenic taphonomic features observed under optical microscopy. Here, we re-investigate a Late Pleistocene ground sloth tooth from northeast Brazil, previously suggested as human-modified based only on optical observation. To characterize the macro- and micro-morphological characteristics of the marks preserved in this tooth and evaluate potential human modification, we used stereomicroscope and scanning electron microscopy (SEM) supplemented by energy dispersive spectroscopy (EDS), UV photoluminescence (UV/PL), synchrotron-based X-ray fluorescence (SR-XRF), and synchrotron micro-computed tomography (SR-µCT). These methods allowed us to discriminate non-anthropogenic taphonomic features (root and sedimentary damage), anthropogenic marks, and histological features. The latter shows the infiltration of exogenous elements into the dentine from the sediments. Our evidence demonstrates the sequence of anthropogenic and non-anthropogenic taphonomic modification of this tooth and supports its initial intentional modification by humans. We highlight the benefits of emerging imaging and spectral imaging techniques to investigate and diagnose human modification in fossil and archaeological records and propose that human modification of tooth tissues should be further considered when studying possibly anthropogenically altered fossil remains.
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Fósiles , Perezosos , Diente , Microtomografía por Rayos X , Brasil , Diente/anatomía & histología , Animales , Humanos , Microscopía Electrónica de Rastreo , Espectrometría por Rayos XRESUMEN
An improvement in the reliability and comparability of tissue characterization results is crucial for enabling further progress in cancer detection and the assessment of therapeutic effects. This can only be achieved by integrating quantitative methods into well-established qualitative characterization routines. This case study presents a hybrid metrological approach for tissue characterisation including vibrational Fourier Transform InfraRed (FTIR) spectroscopy and traceable reference-free X-Ray Fluorescence analysis (XRF). Through the combination of spatially resolved qualitative molecular information with quantitative elemental concentrations an all-encompassing sample characterisation can be provided. The study was performed on tissue sections of syngeneic murine pancreatic ductal adenocarcinoma KPC (KrasG12D/+; Trp53R172H/+; Pdx-1-Cre) tumours ex-vivo. Sections from healthy pancreatic tissues, sham-exposed tumours and tumours subjected to low dose radiotherapy treatment (2 Gray and 6 Gray) were analysed using both methods. Additional sample integrity studies using Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy at the carbon and nitrogen K-edges were performed to assess the effect of sample aging and XRF investigations on the samples. Results showed an increase in the concentrations of elemental biomarkers, including S, K and amide I structures in malignant pancreatic tissue compared to healthy pancreatic tissue. The exposure of tumours to 6 Gy radiation decreases the levels of these elements towards a phenotype seen in the healthy pancreas. A protocol for hybrid investigations is presented, with emphasis on the sample preparation, minimizing the impact of consecutive applied methods on their measurands, and ensuring the compatibility and reliability of achieved results. The study demonstrates the cancer recognition capabilities, and the sensitivity for low dosage radiotherapy treatment monitoring for each method individually and assesses the potential of combining molecular fingerprinting with non-destructive quantitative elemental information for tissue sample characterization.
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Neoplasias Pancreáticas , Espectrometría por Rayos X , Animales , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/radioterapia , Ratones , Espectrometría por Rayos X/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/diagnóstico por imagenRESUMEN
During the investigation of firearm-related incidents, gunshot residues (GSR) can be collected on the scene and individuals (e.g., shooters or bystanders). Their analysis can give valuable information for the reconstruction of the events. Since GSR collection on persons of interest generally occurs a few minutes to hours after discharge, knowledge is needed to understand how organic (O), and inorganic (I) residues are transferred and persist. In this research, the quantities of OGSR and IGSR were assessed on the right and left hands, forearms, face, and nostrils of four shooters. Specimens were collected immediately before the discharge (shooter's blank specimens) and shortly after (30 min) using carbon adhesive stubs. Organic compounds were first extracted from the collection device and analysed using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Subsequently, IGSR particles were detected on the same stub using scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDS). Shooter's blank specimen analysis revealed background contamination of both O and IGSR in the shooter's environment, predominantly attributed to the presence of an indoor shooting range. However, the background quantities generally remained below the associated 30-minute specimen. Thirty minutes after a discharge, higher quantities were generally detected on the shooter's right and left hands than on other collection regions for both GSR types. Forearms and face emerged as interesting collection alternatives, especially in cases where a person of interest may have washed their hands in the interval between the discharge and collection. In contrast, very low amounts of GSR were detected in the nostrils. Furthermore, the results indicated that OGSR and IGSR have different transfer and persistence mechanisms.
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Armas de Fuego , Balística Forense , Mano , Humanos , Balística Forense/métodos , Cara/anatomía & histología , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Nariz , Antimonio/análisis , Antebrazo , Espectrometría de Masas en Tándem , Bario/análisis , Heridas por Arma de Fuego , Cromatografía Líquida de Alta Presión , CiclohexanonasRESUMEN
Although titanium and its alloys are widely used as dental implants, they cannot induce the formation of new bone around the implant, which is a basis for the functional integrity and long-term stability of implants. This study focused on the functionalization of the titanium/titanium oxide surface as the gold standard for dental implants, with electrospun composite fibers consisting of polyvinylpyrrolidone and Ca2+ ions. Polymer fibers as carriers of Ca2+ ions should gradually dissolve, releasing Ca2+ ions into the environment of the implant when it is immersed in a model electrolyte of artificial saliva. Scanning electron microscopy, energy dispersive X-ray spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy confirmed the successful formation of a porous network of composite fibers on the titanium/titanium oxide surface. The mechanism of the formation of the composite fibers was investigated in detail by quantum chemical calculations at the density functional theory level based on the simulation of possible molecular interactions between Ca2+ ions, polymer fibers and titanium substrate. During the 7-day immersion of the functionalized titanium in artificial saliva, the processes on the titanium/titanium oxide/composite fibers/artificial saliva interface were monitored by electrochemical impedance spectroscopy. It can be concluded from all the results that the composite fibers formed on titanium have application potential for the development of osteoinductive and thus more biocompatible dental implants.
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Calcio , Implantes Dentales , Titanio , Titanio/química , Calcio/química , Calcio/metabolismo , Povidona/química , Humanos , Iones/química , Espectroscopía Infrarroja por Transformada de Fourier , Saliva Artificial/química , Materiales Biocompatibles/química , Espectrometría por Rayos X , Osteogénesis/efectos de los fármacosRESUMEN
The studies presented in this paper constitute the first scientific attempt to interpret the manner whereby notched implements made of scapulae were made and used. These implements have been found at numerous European and non-European sites, usually dated to the Neolithic-Early Iron Age (predominantly the Early Bronze Age). Research has examined these products since the beginning of the 20th century, resulting in the development of several hypotheses regarding their functions. This paper presents the analysis results of 41 such artefacts from the early Bronze Age defensive settlement in Bruszczewo (central Poland). This is the largest collection of these products from a single site worldwide. The artefacts were subjected to multi-aspect traceological tests (both technological and functional) using optical, metallographic, and scanning electron microscopes. The residues identified on their surfaces were analysed using optical microscopy and scanning electron microscopy and energy dispersive X-rays spectroscopy. Moreover, the studies reported herein involved extensive experimental research. Consequently, the chain of operations followed in producing these tools was reconstructed and the use-wear traces present on their surfaces were classified; it was determined that these tools were most likely used for threshing cereals but might also have been used for threshing legumes. This is the first proof of threshing in central Europe in the Early Bronze Age and the first scientifically substantiated hypothesis regarding the function of these important artefacts.
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Arqueología , Grano Comestible , Microscopía Electrónica de Rastreo , Grano Comestible/química , Historia Antigua , Fabaceae/química , Europa (Continente) , Polonia , Humanos , Espectrometría por Rayos XRESUMEN
Halophilic archaea are a unique group of microorganisms that thrive in high-salt environments, exhibiting remarkable adaptations to survive extreme conditions. Archaeological wood and El-Hamra Lake serve as a substrate for a diverse range of microorganisms, including archaea, although the exact role of archaea in archaeological wood biodeterioration remains unclear. The morphological and chemical characterizations of archaeological wood were evaluated using FTIR, SEM, and EDX. The degradation of polysaccharides was identified in Fourier transform infrared analysis (FTIR). The degradation of wood was observed through scanning electron microscopy (SEM). The energy dispersive X-ray spectroscopy (EDX) revealed the inclusion of minerals, such as calcium, silicon, iron, and sulfur, into archaeological wood structure during burial and subsequent interaction with the surrounding environment. Archaea may also be associated with detected silica in archaeological wood since several organosilicon compounds have been found in the crude extracts of archaeal cells. Archaeal species were isolated from water and sediment samples from various sites in El-Hamra Lake and identified as Natronococcus sp. strain WNHS2, Natrialba hulunbeirensisstrain WNHS14, Natrialba chahannaoensis strain WNHS9, and Natronococcus occultus strain WNHS5. Additionally, three archaeal isolates were obtained from archaeological wood samples and identified as Natrialba chahannaoensisstrain W15, Natrialba chahannaoensisstrain W22, and Natrialba chahannaoensisstrain W24. These archaeal isolates exhibited haloalkaliphilic characteristics since they could thrive in environments with high salinity and alkalinity. Crude extracts of archaeal cells were analyzed for the organic compounds using gas chromatography-mass spectrometry (GC-MS). A total of 59 compounds were identified, including free saturated and unsaturated fatty acids, saturated fatty acid esters, ethyl and methyl esters of unsaturated fatty acids, glycerides, phthalic acid esters, organosiloxane, terpene, alkane, alcohol, ketone, aldehyde, ester, ether, and aromatic compounds. Several organic compounds exhibited promising biological activities. FTIR spectroscopy revealed the presence of various functional groups, such as hydroxyl, carboxylate, siloxane, trimethylsilyl, and long acyl chains in the archaeal extracts. Furthermore, the archaeal extracts exhibited antioxidant effects. This study demonstrates the potential of archaeal extracts as a valuable source of bioactive compounds with pharmaceutical and biomedical applications.
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Arqueología , Lagos , Madera , Madera/química , Madera/microbiología , Lagos/microbiología , Egipto , Archaea , Espectroscopía Infrarroja por Transformada de Fourier , Filogenia , Espectrometría por Rayos XRESUMEN
Photobiomodulation therapy (PBMT) is a form of treatment commonly used for routine clinical applications, such as wound healing of the skin and reduction of inflammation. Additionally, PBMT has been explored for its potential in pain relief. In this work, we investigated the effect of PBMT on ion content within the 50B11 sensory neurons cell line in vitro using X-Ray fluorescence (XRF) and atomic force microscope (AFM) analysis. Two irradiation protocols were selected utilizing near-infrared laser lights at 800 and 970 nm, with cell fixation immediately following irradiation. Results showed a decrease in Calcium content after irradiation with both protocols, and with lidocaine, used as an analgesic control. Furthermore, a reduction in Potassium content was observed, particularly evident when normalized to cellular volume. These findings provide valuable insights into the molecular impact of PBMT within 50B11 sensory neurons under normal conditions. Such understanding may contribute to the wider adoption of PBMT as a therapeutic approach.
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Calcio , Rayos Infrarrojos , Terapia por Luz de Baja Intensidad , Células Receptoras Sensoriales , Animales , Células Receptoras Sensoriales/efectos de la radiación , Células Receptoras Sensoriales/metabolismo , Calcio/metabolismo , Ratones , Línea Celular , Espectrometría por Rayos X , Microscopía de Fuerza Atómica , Potasio/metabolismo , Potasio/química , Lidocaína/farmacologíaRESUMEN
BACKGROUND: White spot lesions are a widespread undesirable effect, especially prevalent during fixed orthodontic treatments. The study compared the in vitro enamel remineralization potential of undemineralized dentin matrix (UDD) versus chicken eggshell powder (CESP) for artificially induced enamel lesions. METHODS: 100 caries-free and sound maxillary premolars were randomly divided into four groups each contain 25 teeth: Group I (Baseline): No treatment was done to the enamel surface. Group II (Negative control ): The enamel surface of the teeth underwent demineralization using demineralizing solution to create artificial carious lesions then kept in artificial saliva. Group III (CESP treated): After demineralizing the tooth surface, the teeth have been suspended in the CESP remineralizing solution. Group IV (UDD treated): After enamel demineralization, the teeth were suspended in UDD remineralizing solution. The remineralization potential was assessed by Vickers microhardness testing, scanning electron microscopic examination (SEM), and energy dispersive X-ray (EDX). RESULTS: The current study demonstrated an increase in the mean microhardness of CESP and UDD-treated groups; however, It was nearer to the baseline level in the UDD group. SEM imaging revealed greater enamel remineralization in the UDD group compared to the remaining groups. The UDD group disclosed complete coverage for the prismatic enamel compared to the CESP group, which revealed a partially remineralized enamel surface. Interestingly, the Ca/P ratio increased significantly in the CESP group compared to the negative control group. In contrast, a higher significant increase in the mean Ca/P ratios was recorded in the UDD group compared to the test groups. CONCLUSION: biomimetic UDD and CESP powder should be utilized to treat enamel early carious lesions. However, UDD demonstrated the most significant remineralization potential.
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Pollos , Caries Dental , Esmalte Dental , Dentina , Cáscara de Huevo , Dureza , Microscopía Electrónica de Rastreo , Remineralización Dental , Animales , Remineralización Dental/métodos , Caries Dental/terapia , Humanos , Esmalte Dental/efectos de los fármacos , Dentina/efectos de los fármacos , Polvos , Técnicas In Vitro , Desmineralización Dental , Espectrometría por Rayos X , Diente Premolar , Saliva Artificial , Calcio/análisis , Calcio/uso terapéuticoRESUMEN
BACKGROUND: Arsenic, classified as a priority pollutant and human carcinogen by the IARC, is subject to stringent regulatory limits in food and water. Among various arsenic species found in water samples, arsenite (As(III)) is identified as the most toxic form. Given the limitations of conventional spectroscopic techniques in speciation analysis, there is a crucial need for innovative and sustainable methodologies that enable arsenic speciation. Simplifying these methodologies is essential for widespread applicability and effective environmental monitoring. RESULTS: This study proposes a simple and cost-effective analytical methodology for speciating inorganic arsenic in water samples. The method involves extracting As(III) into a polymer inclusion membrane (PIM) containing the extractant Cyanex 301 (bis(2,4,4-trimethylpentyl) dithiophosphinic acid), followed by analysis using energy dispersive X-ray fluorescence (EDXRF) spectrometry. The concentration of arsenate was measured after a reduction step using a thiosulfate/iodide mixture. This simple methodology allows a limit of quantification for trivalent arsenic (2 µg L-1), which is well below the World Health Organization's recommended maximum permissible level of As in drinking water (10 µg L-1). The method that is developed allows the determination of As at trace levels in waters with naturally occurring arsenic. SIGNIFICANCE AND NOVELTY: This study represents a significant advance in the field, providing a novel and efficient methodology for arsenic speciation analysis in water samples. By combining the advantages of polymer inclusion membrane (PIM) extraction with energy dispersive X-ray fluorescence (EDXRF) spectrometry, this study offers a cost-effective and environmentally friendly approach to address the critical issue of arsenic contamination in water sources, thereby contributing to enhanced environmental monitoring and public health protection.
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Arsénico , Polímeros , Espectrometría por Rayos X , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Polímeros/química , Arsénico/análisis , Espectrometría por Rayos X/métodos , Membranas ArtificialesRESUMEN
This study investigated phytic acid (IP6) effect on chemical, structural, and mechanical characteristics of nickel-titanium (NiTi) files. The tested files were equally divided into groups according to the immersion protocol: sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), IP6, EDTA followed by NaOCl, and IP6 followed by NaOCl. These groups were then compared in terms of Ni, Ti, and chromium (Cr) ions release from the files. Microstructural changes using field emission scanning electron microscope (Fe-SEM) and energy dispersive X-ray spectroscopy (EDX) and surface roughness were analyzed. The mechanical characterization was conducted using cyclic fatigue resistance test. Fractured segments were scanned under SEM. Statistical analysis was performed using one-way ANOVA, Tukey test, Kruskal-Wallis test and Mann-Whitney U test. Results showed that NaOCl caused significant release of Cr, followed by IP6 and EDTA (P < 0.05). When files were pre-immersed in EDTA, NaOCl tended to induce less release of Ti and Cr. EDX evaluation revealed that the main surface elements were Ni, Ti, carbon, and oxygen. EDTA group contained the highest amount of carbon, while the control group showed the lowest. Surface roughness evaluation revealed no significant differences between groups despite the minor increases after immersion in certain groups. Black areas were observed in the NaOCl group which indicated corrosion. However, the cyclic fatigue test showed no significant differences between the groups.
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Níquel , Ácido Fítico , Titanio , Ácido Fítico/química , Titanio/química , Níquel/química , Propiedades de Superficie , Hipoclorito de Sodio/química , Microscopía Electrónica de Rastreo , Ácido Edético/química , Ensayo de Materiales , Espectrometría por Rayos X , Cromo/química , Preparación del Conducto RadicularRESUMEN
The use of composted sludge from sewage treatment plants as a soil amendment is a common practice of recycling nutrients like organic carbon, nitrogen, and phosphorus. The sewage generated in larger cities of developing countries is often contaminated with various heavy metals (HMs) that ultimately end up in composted sludge. Thus, using such composted sludge is likely to pose ecological and human health risks. Hence, the knowledge of HM translocation in sludge-soil-plant systems is of vital importance. The present study was aimed at investigating the HM translocation in sludge-soil-plant system. The HM translocation was measured using synchrotron radiation-induced x-ray fluorescence spectrometry and atomic absorption spectroscopic techniques. The results indicated high HM mobility (up to 2628.5 mg kg-1) from sludge to spinach plant. The metal accumulation (mg kg-1) ranged in the order-Fe (950.55-2628.5) > Zn (20.11-172.13) > Cu (13.86-136.17) > Mn (2.13-34.67) > Cd (0.11-31.17) > Pb (1.50-30.16) > Co (0.18-9.85) As (0.02-7.80) > Cr (0.01-5.69). This observed accumulation depended on the volume of sewage being treated in the sewage treatment plant (STP) and varied in the order control < (8 MLD Bhagwanpur, STP 1) < (80 MLD Dinapur, STP2) < (140 MLD Dinapur, STP3) hence the HM load coming into STPs. The metal transfer factor, bioconcentration factor, and translocation factor values also correlated with the abundance of Fe, Cu, Pb, Cd, and Zn in spinach root and shoot compartments. The carcinogenic risk for heavy metal carcinogens like As, Cd, Cr, and Pb revealed children being more prone to cancer upon spinach consumption. Hence, it is necessary to assess the heavy metals present in the sludge prior to its application in agricultural fields.
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Metales Pesados , Aguas del Alcantarillado , Contaminantes del Suelo , Espectrometría por Rayos X , Sincrotrones , Metales Pesados/análisis , Aguas del Alcantarillado/química , Contaminantes del Suelo/análisis , Medición de Riesgo , Humanos , Spinacia oleracea/química , Compostaje/métodos , Suelo/químicaRESUMEN
OBJECTIVES: This study aimed to evaluate and compare the impact of cigarette smoking (CS) and heated tobacco (HT) on the alteration of color and ultrastructural characteristics of human enamel and cementum. BACKGROUND: According to tobacco companies, a less harmful substitute for CS is HT products. Nevertheless, comprehensive research on the effects of HT on tooth structures has been lacking. This study aimed to evaluate and compare the impact of CS and HT on the alteration of color and ultrastructural characteristics of human enamel and cementum. MATERIALS AND METHODS: Thirty intact and noncarious human maxillary premolars extracted for orthodontic treatment purposes, previously disinfected, were used in the study. The specimens were randomly separated into six groups (n = 10), as follows: Group 1: enamel without smoking exposure; Group 2: enamel exposed to CS; Group 3: enamel exposed to HT; Group 4: cementum without smoking exposure; Group 5: cementum exposed to CS; and Group 6: cementum exposed to HT. The measurement of color change was conducted using a spectrophotometer. The surface alterations and mineral composition of enamel and cementum were evaluated using scanning electron microscopy and energy-dispersive X-ray spectroscopy. ANOVA test followed by Tukey's post hoc test was used to determine significant differences between groups. RESULTS: Results showed that CS had a more pronounced effect on enamel and cementum color changes than HT. The impact of CS and HT on color changes was more evident in cementum than in enamel. Surface morphology of enamel and cementum showed alterations in histology following exposure to both smoking types. Moreover, the mineral content experienced a significant reduction after using CS and HT. The reduction in calcium content after CS and HT exposure was similar. However, HT led to a significant decrease in the phosphorus content of enamel when compared with CS. At the same time, CS exposure in cementum resulted in a more significant reduction in Ca/P ratio than HT. CONCLUSIONS: Although HT may appear to present a lower danger to hard dental tissues than CS, it is not entirely harmless. CS results in more color changes on the enamel and cementum of teeth. Both smoking methods affected the mineral content of teeth, with CS having a significant effect on the roots, while HT significantly affected the crowns' mineral composition.
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Fumar Cigarrillos , Colorimetría , Cemento Dental , Esmalte Dental , Microscopía Electrónica de Rastreo , Productos de Tabaco , Humanos , Cemento Dental/patología , Cemento Dental/química , Esmalte Dental/química , Esmalte Dental/efectos de los fármacos , Productos de Tabaco/efectos adversos , Colorimetría/métodos , Fumar Cigarrillos/efectos adversos , Calor/efectos adversos , Espectrometría por Rayos X , Diente Premolar , ColorRESUMEN
Worldwide, silicified woods are found in many geological formations. Significantly, the organic materials of wood are no longer dominant; almost all wood fossils have been mineralized into inorganic silica materials. These unique geological processes must be understood to develop better understanding on organic material fossilization, particularly in the micron scale. Therefore, our aim was to characterize the composition of silicified wood using comprehensive microanalysis. The methods utilized were XRF, ICP-MS, XRD, FTIR, and FE-EPMA. Specimens are from Jasinga, West Java, Indonesia. The results showed that wood silicification was controlled by the infiltration of silica from the host rock into the spaces of the wood structure. In Jasinga, they are controlled by Pliocene tuffaceous sedimentary rocks. The ratio of silica phases revealed a trend in the degree of silicification. Besides silica, the distribution of trace elements also demonstrates the geochemical interaction between the wood fossil and host rock. Wood fossils are affected by the gradual replacement of organic carbon-based materials with silica through silicification. Silica enrichment occurs in the internal of wood, facilitates permineralization and recrystallization. Silica replaces organic material and preserves the wood structures. The microanalytical approach provides comprehensive perspectives on wood petrification, leads to better insights for paleontological studies.
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Fósiles , Dióxido de Silicio , Madera , Madera/química , Indonesia , Dióxido de Silicio/química , Sedimentos Geológicos/química , Sedimentos Geológicos/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X , Espectrometría por Rayos XRESUMEN
The corrosion of magnesium (Mg)-based bioabsorbable implanting devices is influenced by implantation environment which dynamically changes by biological response including wound healing. Understanding the corrosion mechanisms along the healing process is essential for the development of Mg-based devices. In this study, a hematoma model was created in a rat femur to analyze Mg corrosion with hematoma in the early stage of implantation. Pure Mg specimen (99.9%,Ï1.2 × 6 mm) was implanted in rat femur under either hematoma or non-hematoma conditions. After a designated period of implantation, the specimens were collected and weighed. The insoluble salts formed on the specimen surfaces were analyzed using scanning electron microscopy, energy-dispersive x-ray spectroscopy, and Raman spectroscopy on days 1, 3, and 7. The results indicate that hematomas promote Mg corrosion and change the insoluble salt precipitation. The weight loss of the hematoma group (27.31 ± 5.91 µg mm-2) was significantly larger than that of the non-hematoma group (14.77 ± 3.28 µg mm-2) on day 7. In the non-hematoma group, carbonate and phosphate were detected even on day 1, but the only latter was detected on day 7. In the hematoma group, hydroxide was detected on day 1, followed by the formation of carbonate and phosphate on days 3 and 7. The obtained results suggest the hypoxic and acidic microenvironment in hematomas accelerates the Mg corrosion immediately after implantation, and the subsequent hematoma resorption process leads to the formation of phosphate and carbonate with organic molecules. This study revealed the risk of hematomas as an acceleration factor of the corrosion of Mg-based devices leading to the early implant failure. It is important to consider this risk in the design of Mg-based devices and to optimize surgical procedures controlling hemorrhage at implantation and reducing unexpected bleeding after surgery.
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Implantes Absorbibles , Fémur , Hematoma , Magnesio , Ensayo de Materiales , Ratas Sprague-Dawley , Animales , Magnesio/química , Ratas , Corrosión , Masculino , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Espectrometría Raman , Propiedades de Superficie , Materiales Biocompatibles/químicaRESUMEN
OBJECTIVE: The aim of this study was to investigate the effect of remineralization agents such as fluoride varnish and P11-4, alone and in combination with Er: YAG laser, on in-vitro hard tissue repair in artificial enamel lesions. MATERIALS AND METHODS: A total of sixty enamel surfaces of 4 × 5 mm in size were created on both the buccal and lingual sides of thirty extracted wisdom teeth. Remineralization agents were applied to the specimens that were grouped as follows: Group 1, control; Group 2, fluoride varnish (FV); Group 3, P11-4; Group 4, laser; Group 5, laser + FV; and Group 6, laser + P11-4. The fluorescence level was determined with DiagnoDent. The enamel mineral density, area and volume, and caries lesion area and volume were determined with micro-computed tomography (µCT), surface features were evaluated using scanning electron microscopy (SEM), and elemental analysis was performed using energy dispersive x-ray spectroscopy (EDS) . RESULTS: For specimens treated only with self-assembling peptide P11-4, the caries lesion area (mm2) values were 38.19 and 21.62, and the caries lesion volume (mm3) values were 6.27 and 2.99, respectively for pre- and post-treatment. In combination usage of self-assembling peptide P11-4 and laser, the caries lesion area (mm2) values were 38.39 and 16.91, and the caries lesion volume (mm3) values were 11.15 and 3.64, respectively for pre- and post-treatment. In the application of the P11-4 alone and in combination with laser, there was a statistically significant decrease in DiagnoDent values, an increase in enamel volume(mm3),enamel area(mm2) and mineral density(g/cm3) values and a decrease in caries lesion volume(mm3) and area(mm2) obtained by µCT, and an increase in %Ca and %F values obtained by SEM/EDS analysis (p < 0.05). It was discovered that the samples treated with P11-4 had a considerably higher rise in the Ca/P ratio than the samples treated with FV (p < 0.05). The calcium content increased significantly more when P11-4 application was combined with laser irradiation (p < 0.05). CONCLUSIONS: The combined use of self-assembling peptide P11-4 and laser accelerated the remineralization process and increased the remineralization capacity. CLINICAL RELEVANCE: FV and P11-4, alone or in combination with laser, can be successfully used as remineralization agents in initial enamel caries.
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Caries Dental , Esmalte Dental , Fluoruros Tópicos , Láseres de Estado Sólido , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Microtomografía por Rayos X , Caries Dental/terapia , Humanos , Técnicas In Vitro , Láseres de Estado Sólido/uso terapéutico , Esmalte Dental/efectos de los fármacos , Cariostáticos , Remineralización Dental/métodos , Propiedades de Superficie , Péptidos , OligopéptidosRESUMEN
OBJECTIVE: To study the effect of incorporating chitosan and fluoride-loaded chitosan nanoparticles into a glass-ionomer cement (GIC) to prevent secondary caries. MATERIALS AND METHODS: A standard cervical cavity (mesio-distal width 6 mm, cervico-occlusal width 2 mm, and depth 2 mm) was prepared on 30 molars for the following restoration groups: group 1, conventional GIC restoration; group 2, chitosan (10%) modified GIC restoration; group 3, fluoride loaded chitosan nanoparticles (10%) modified GIC restoration. The restored teeth were subjected to 1,500 thermal cycles before undergoing a multi-species cariogenic biofilm challenge. The restored teeth were examined by micro-computed tomography (micro-CT), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). Data were analyzed by the one-way ANOVA, Tukey HDS, Kruskal Wallis, and Dunn's test. RESULTS: Micro-CT determined outer lesion depths for groups 1-3 were: 614 ± 20 µm, 589 ± 17 µm, and 560 ± 19 µm respectively. Both modifications with chitosan and fluoride-loaded chitosan nanoparticles significantly affected outer lesion depth (p < 0.05). The modification with fluoride-loaded chitosan nanoparticles statistically significantly decreased the outer lesion depth compared to all other groups (p < 0.05). SEM/EDX showed an increase of calcium, phosphorus, and fluoride at the root dentine adjacent to the restoration in groups 2 and 3 (modified GIC). This increase was statistically significantly higher in the group modified with fluorine-loaded nano chitosan particles compared to the other groups (p < 0.05). CONCLUSION: Incorporation of 10% chitosan and 10% fluoride-loaded chitosan nanoparticles into GIC restorative material can prevent secondary root caries development. 10% fluoride-loaded chitosan nanoparticles were more effective. CLINICAL SIGNIFICANCE: Glass ionomer cement modified with fluoride-loaded chitosan nanoparticles may be a promising restorative material in pediatric and preventive dentistry due to their controlled release properties.
Asunto(s)
Quitosano , Caries Dental , Fluoruros , Cementos de Ionómero Vítreo , Microscopía Electrónica de Rastreo , Nanopartículas , Espectrometría por Rayos X , Microtomografía por Rayos X , Cementos de Ionómero Vítreo/química , Quitosano/química , Nanopartículas/química , Fluoruros/química , Caries Dental/prevención & control , Humanos , Técnicas In Vitro , Cariostáticos/química , Diente Molar , Restauración Dental Permanente/métodos , Ensayo de Materiales , Propiedades de Superficie , Biopelículas/efectos de los fármacosRESUMEN
OBJECTIVES: To investigate urushiol's potential as a dentin cross-linking agent, promoting remineralization of etched dentin and preventing activation of endogenous proteases causing collagen degradation within the hybrid layer. The goal is to improve bond strength and durability at the resin-dentin interface. METHODS: Urushiol primers with varying concentrations were prepared using ethanol and dimethyl sulfoxide (DMSO) as solvents. Dentin from healthy molars underwent grinding and acid etching for 15 s, followed by a 1min application of urushiol primer. After 14 and 28 days of remineralization incubation and remineralization were used to assess by Attenuated Total Reflection Fourier Transform Infrared spectroscopy (ATR-FTIR), Micro-Raman spectroscopy, X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Vickers Hardness, Scanning Electron Microscopy (SEM), and Energy X-ray dispersive spectroscopy (EDS). The overall performance of urushiol primers as dentin adhesives was observed by microtensile bond strength (µTBS) testing and nanoleakage assessment. Investigated the inhibitory properties of the urushiol primers on endogenous metalloproteinases (MMPs) utilizing in situ zymography, and the cytotoxicity of the primers was tested. RESULTS: Based on ATR-FTIR, Raman, XRD, EM-EDS and Vickers hardness analyses, the 0.7%-Ethanol group significantly enhanced dentin mineral content and improved mechanical properties the most. Pretreatment notably increased the µTBS of restorations, promoted the stability of the mixed layer, and reduced nanoleakage and MMPs activity after 28 days. SIGNIFICANCE: The urushiol primer facilitates remineralization in demineralized dentin, enhancing remineralization in etched dentin, effectively improving the bonding interface stability, with optimal performance observed at a 0.7 wt% concentration of the urushiol primer.
Asunto(s)
Dentina , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Solventes , Resistencia a la Tracción , Remineralización Dental , Humanos , Espectroscopía Infrarroja por Transformada de Fourier , Dentina/efectos de los fármacos , Remineralización Dental/métodos , Solventes/química , Difracción de Rayos X , Recubrimientos Dentinarios/química , Espectrometría Raman , Propiedades de Superficie , Recubrimiento Dental Adhesivo/métodos , Microscopía de Fuerza Atómica , Técnicas In Vitro , Grabado Ácido Dental , Espectrometría por Rayos X , Diente Molar , Reactivos de Enlaces Cruzados/química , DurezaRESUMEN
OBJECTIVE: The aim of this study was to evaluate the effect of an adhesive loaded with 0.2 % copper (Cu) and 5 % zinc oxide (ZnO) nanoparticles (Nps) on its adhesive properties and enzymatic activity at the hybrid layer ex vivo in a randomized clinical model. METHODS: Fifteen patients participated in this study, and a total of 30 third molars were used. Occlusal cavities (4 × 4 × 2 mm) were made in each tooth, and randomly divided into 2 groups: (i) Experimental group: commercial adhesive loaded with 0.2wt % CuNps and 5wt % ZnONps; and (ii) Control Group: non-loaded commercial adhesive. Teeth were restored with resin composite. Thirty days later, extractions were performed. Extracted teeth were longitudinally sectioned. Nps in powder were characterized by field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray (EDX) analysis. Microtensile bond strength (µTBS), degree of conversion (DC), and nanoleakeage (NL) tests were executed. In situ zymography (Zym) was performed to evaluate the gelatinolytic activity at the hybrid layer. Student's t-test (α = 0.05) was applied for all tests. RESULTS: µTBS and DC did not show significant differences (p > 0.05) between both groups. However, NL and gelatinolytic activity at the hybrid layer showed significant values (p < 0.05) for experimental group in comparison with control group. CONCLUSION: The addition of 0.2 % CuNps and 5 % ZnONps to a universal adhesive decreases NL and gelatinolytic activity at the hybrid layer, without jeopardizing its adhesive properties. SIGNIFICANCE: This randomized clinical trial with ex vivo analysis demonstrate that a commercial adhesive modified with 0.2wt % Cu and 5wt % ZnO Nps that does not affect its adhesive properties, reducing gelatinolytic activity and nanoleakage at the hybrid layer, which should contribute to an improvement of long term bonding-dentine clinical performance.