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1.
J Clin Pediatr Dent ; 48(3): 59-67, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38755983

RESUMEN

The importance of aesthetics in children has increased over time. Therefore, this multicenter randomized clinical trial aimed to analyze and compare three-dimensional (3D)-printed resin crowns (RCs) as a potential alternative to stainless-steel crowns (SSCs) for restoring primary molars with extensive carious lesions. According to the null hypothesis, no statistically significant difference was observed in restoration failure between RC and SSC groups. A total of 56 primary molars after pulp treatment at two dental hospitals were included. After pulp treatment, the teeth were randomly divided into two groups: SSCs (n = 28) and RCs (n = 28). At 1 week and 3, 6 and 12 months, the Quigley-Hein plaque index (QHI), gingival index (GI), occlusal wear, and survival rate were assessed by examination, radiography and alginate impressions. No significant difference in QHI was observed between the two groups. However, the GI at 12 months and occlusal wear in the RC group were significantly higher than those in the SSC group (p < 0.05). The survival rates were 100% in the SSC group and 82.1% in the RC group (p = 0.047). Cracks and discoloration were also observed in the RCs. Within the limitations of this study, 3D-printed RCs are aesthetically superior to SSCs and clinically easy to repair. However, if clinical effectiveness and safety are improved, RCs could potentially become a viable aesthetic alternative in the future.


Asunto(s)
Coronas , Diente Molar , Impresión Tridimensional , Acero Inoxidable , Diente Primario , Humanos , Femenino , Masculino , Niño , Caries Dental/terapia , Restauración Dental Permanente/métodos , Preescolar , Diseño de Prótesis Dental , Índice Periodontal , Fracaso de la Restauración Dental
2.
Mar Pollut Bull ; 200: 116056, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266480

RESUMEN

Microplastic contamination is ubiquitous and can be transferred through the food chain to humans. However, studies on microplastic size have mainly focused on large animals with a body length >20 mm. To address this gap, we conducted a comprehensive review of 169 laboratory studies to determine the edible size of microplastics for macrofauna and flora in aquatic and soil biota. Our findings indicate that microplastics with a size of <300 µm and 1 µm, respectively, are edible for these organisms, which are positioned at the base of the food chain. We also analyzed intake and depuration patterns and identified factors affecting microplastic ingestion. Our study fills an important knowledge gap by identifying the range of microplastic sizes that can enter the food chain and be transferred to humans. The study findings have strong implications for the ecological risk assessment of microplastics and suggest a starting point for mitigating this threat.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Humanos , Plásticos , Suelo , Contaminantes Químicos del Agua/análisis , Biota , Ingestión de Alimentos , Monitoreo del Ambiente , Ecosistema , Organismos Acuáticos
3.
J Hazard Mater ; 465: 133520, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38232553

RESUMEN

Assessing the ecological risks of microplastics is difficult because of the limited availability of reliable ecotoxicity data. Although freshwater is a valuable sink for microplastics, the current framework for ecological risk assessment using traditional toxicity data is not applicable to freshwater ecosystems. Herein, species sensitivity distribution (SSD) curves were compared for edible and all microplastics exposed to aquatic organisms based on traditional endpoint-based and all-endpoint-based databases. Freshwater toxicity data for microplastics were screened after verifying microplastic presence in test species (56 toxicity datapoints for one microalga, three water fleas, one fish, and one crab; 0.02-100 µm-sized microplastics). SSD and curve parameters were compared with or without non-traditional toxicity endpoints. The HC50 in all endpoint databases was more sensitive than that in the traditional endpoint database and showed a good fit. SSD curves derived from the database for all microplastics were compared and analyzed with edible microplastics. HCx increased for edible microplastics (0.02-100 µm-sized) than for all microplastics (0.02-200 µm-sized), and the size of edible microplastics was lower than of all microplastics. Thus, using non-traditional toxicity data, the SSD approach compensates for the limited ecotoxicity data on microplastics while considering the internalization of microplastics in biota.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Plásticos , Ecosistema , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Agua Dulce , Biota
4.
J Dent ; 137: 104684, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37660882

RESUMEN

OBJECTIVES: This study aimed to verify the non-inferiority of Endocem MTA Premixed and Well-Root PT, compared with ProRoot MTA in the pulpotomy of primary molars. In addition, we tried to determine the factors that affect the prognosis of pulpotomy in primary molars. METHODS: This randomized clinical trial enrolled 158 molars of 52 children; 153 teeth were finally included and divided into three groups: ProRoot MTA (n = 50), Endocem MTA Premixed (n = 53), and Well-Root PT (n = 50). Clinical and radiographic follow-up was performed at 3, 6, and 12 months postoperatively and at the last visit post-treatment. Data were analyzed using the Fisher's exact test, Cox regression analysis, and the Kaplan-Meier survival curve method. RESULTS: The success rates in the ProRoot MTA, Endocem MTA Premixed, and Well-Root PT were 92, 84.9 and 82%, respectively. The cumulative survival rates did not differ significantly among the materials. Among the investigated variables, only ΔF and ΔF max significantly affected the success rates. In the multivariate survival tree model, significant unfavorable survival was observed when the ΔF value was -14.4 or less (hazard ratio, 7.56; P = 0.0295). CONCLUSIONS: Considering the clinical effectiveness of Endocem MTA Premixed and Well-Root PT and the operational convenience as a premixed type, they can be used as advantageous materials in the pulpotomy of primary molars in pediatric patients. The QLF method is a useful diagnostic method that can establish treatment plans and determine the prognosis of pulpotomy based on the ΔF value in primary molars. CLINICAL SIGNIFICANCE: Endocem MTA Premixed and Well-Root PT can confer high success rates and are non-inferior to ProRoot MTA in pulpotomy for primary molars. We also showed that QLF technology can be applied to predict the success/failure and prognosis of pulpotomies in primary molars.


Asunto(s)
Cemento Dental , Pulpotomía , Humanos , Niño , Compuestos de Calcio/uso terapéutico , Diente Molar/diagnóstico por imagen , Diente Molar/cirugía
5.
J Hazard Mater ; 459: 132174, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37531763

RESUMEN

Owing to their ubiquitous nature, microplastics are a major environmental concern. This study reviewed the toxicity data of microplastics in marine water, and analyzed their species sensitivity distribution (SSD) curves and hazardous concentrations (HCs). Toxicity database of no-observed effect concentration (NOEC), 50% effect concentration (EC50), and highest observed no-effect concentration (HONEC), and lethal, developing, reproductive, biochemical, and behavioral toxicity endpoints was used. Using 169 chronic NOEC databases, all non-traditional toxicity endpoint databases showed stronger HC values, better fit, and more variable toxicity sensitivity than those derived from traditional values. Moreover, using 426 chronic NOEC, EC50, and HONEC data points, HC values calculated from traditional plus HONEC toxicity values showed weaker HC values, slightly better fit, and more variable toxicity sensitivity than those derived from traditional toxicity values. The SSD approach using non-traditional toxicity and marine water toxicity data can expand the marine water toxicity database, including information on SSD curves and HCs of diverse microplastics.


Asunto(s)
Organismos Acuáticos , Contaminantes Químicos del Agua , Microplásticos/farmacología , Plásticos/toxicidad , Agua/farmacología , Contaminantes Químicos del Agua/análisis
6.
Mar Pollut Bull ; 192: 114999, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37182239

RESUMEN

Tire particles (TPs) generated on roads are a main contributor to microplastic environmental pollution. In this study, TP leachates from three vehicle types (bicycle, car, and electric scooter) were prepared. TP leachate toxicity impacts on three organisms (Vigna radiata, Daphnia magna, and Danio rerio) were analyzed, in addition to their chemical compositions. Zinc and benzothiazole were the most commonly detected compounds in all three leachate types. Growth inhibition of V. radiata, mortality of D. magna, and abnormality in D. rerio were observed as toxicological impacts. Overall, the lethal effects of TP leachates showed a significant, positive relationship with zinc and benzothiazole concentration. The results confirmed that TPs are complex contaminants, which release chemicals into the environment that affect both soil and aquatic organisms. These findings highlight the need for stricter control measures and environmental regulations to mitigate the ecotoxic effects of TPs and related contaminants across ecosystems and trophic levels.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Animales , Plásticos/farmacología , Ecosistema , Daphnia , Zinc/toxicidad , Pez Cebra , Contaminantes Químicos del Agua/química
7.
Children (Basel) ; 10(3)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36979987

RESUMEN

This randomized controlled trial aimed to educate patients and manage oral hygiene remotely via a smart toothbrush (ST) by using mobile applications and to improve oral hygiene and habits by evaluating the plaque state via images from a Q-ray cam, which is a quantitative light-induced fluorescence (QLF) digital imaging device. In total, 68 children (aged 6-12 years) were randomly divided into three groups. Group I was assigned an electro-toothbrush (ET), group II was assigned a smart toothbrush (ST), and group III used a manual toothbrush (MT). Each group used an assigned toothbrush and was checked after 1 and 3 months. Oral hygiene status was evaluated using the patient hygiene performance (PHP) index and fluorescent plaque index (FPI), which are presented in the QLF program. In addition, questionnaires on oral health behaviors and attitudes were also evaluated. There was a 0.24 decrease in the PHP index and a 1.40 decrease in the simple hygiene score three months later compared with the baseline in the ST group, with no significant difference between the three methods (p = 0.518, p = 0.626). Many group II participants said that ST helped with oral hygiene, and they were willing to use it continuously. In addition, all participants' brushing times and attitudes toward oral hygiene improved after oral hygiene education using a Q-ray cam. Therefore, the use of STs provided good dental health education and a plaque-decreasing effect to children aged 6-12 years old. Furthermore, the QLF device can be used as a useful tool for maintaining good oral hygiene in children.

8.
J Hazard Mater ; 445: 130532, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-36495642

RESUMEN

Microplastic pollution has become a major environmental problem, indicating the need to implement quantitative governance standards in combination with reducing or banning single-use plastic. Previous studies have predicted no-effect concentrations for limited microplastic-based toxicity data but have not considered environmentally relevant sizes, shapes, or polymers. To provide high quantity and quality data for microplastics of different sizes, shapes, or polymer compositions, non-traditional and traditional toxicity data may need to be considered in combination. In this study, we reviewed toxicity data for microplastics in freshwaters from 2018 to 2022 and analyzed the toxicity data using traditional and non-traditional methods. Based on 166 chronic traditional toxicity data points, the hazard concentration (HC) values calculated from non-traditional toxicity endpoints or all toxicity endpoints were lower than those calculated from traditional toxicity endpoints. Based on 398 chronic traditional plus non-traditional toxicity data points, the HC values calculated from traditional plus non-traditional values were higher than those calculated from traditional toxicity values. With these results, we developed a new framework for deriving microplastic-specific hazardous concentrations, one that especially considers non-traditional toxicity endpoints and values for microplastics. Overall, this study offers a basis for future management strategies and associated frameworks for mitigating microplastic toxicity.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Microplásticos/toxicidad , Plásticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Agua Dulce , Polímeros
9.
Synth Biol (Oxf) ; 7(1): ysac010, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35949424

RESUMEN

Plate readers are commonly used to measure cell growth and fluorescence, yet the utility and reproducibility of plate reader data is limited by the fact that it is typically reported in arbitrary or relative units. We have previously established a robust serial dilution protocol for calibration of plate reader measurements of absorbance to estimated bacterial cell count and for green fluorescence from proteins expressed in bacterial cells to molecules of equivalent fluorescein. We now extend these protocols to calibration of red fluorescence to the sulforhodamine-101 fluorescent dye and blue fluorescence to Cascade Blue. Evaluating calibration efficacy via an interlaboratory study, we find that these calibrants do indeed provide comparable precision to the prior calibrants and that they enable effective cross-laboratory comparison of measurements of red and blue fluorescence from proteins expressed in bacterial cells.

10.
J Hazard Mater ; 437: 129362, 2022 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-35716575

RESUMEN

Tire particles are generated by the abrasion of tire treads on roads and are major contributors to microplastics in soil environments. Contamination by tire wear particles worsens annually as the use of personal mobilities increases. Tire particles (112-541 µm) were obtained from three types of personal mobility tires (bicycle, car, and electric scooter) and exposed to plants (Vigna radiata) and springtails (Folsomia candida) for 28 d to assess the toxicity of each tire-particle type. The laboratory-generated tire particles exhibit adverse effects depending on the origin of the tire or test species. Particles from bicycle or electric-scooter tires changed the soil's bulk density and water holding capacity and adversely affected plant growth. Car tire particles had leached various organic compounds and induced detrimental effects on springtails (adult and offspring growth). We concluded that laboratory-generated tire particles (frow new tires) can affect the soil environment by changing soil properties and leaching chemicals; thus, causing adverse effects on soil organisms. Since this study found tire particle toxicity on soil organisms, it would be possible to compare the various contamination levels in areas near road soil and other clean soils.


Asunto(s)
Automóviles , Suelo , Ciclismo , Microplásticos , Plásticos
11.
J Hazard Mater ; 429: 128306, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35101758

RESUMEN

Shoe sole fragments are generated by sole abrasion, which is unavoidable. These fragments can enter the soil ecosystem. However, limited studies have evaluated their effects on soils and plants. Here, we aimed to evaluate the toxicity of shoe sole fragments on a crop plant, Vigna radiata (mung bean). Shoe sole fragments (size: 57-229 µm) were obtained from four shoe types (trekking shoes, slippers, sneakers, and running shoes) and plant toxicity assessments were performed. Additionally, the fragments were leached for 30 d, and potentially toxic leachates were identified. Shoe sole fragments exhibited adverse effects depending on the shoe type. The fragments of soles from sneakers increased the bulk density of the soil but reduced its water holding capacity. Moreover, the microplastic fragments and leachates directly affected plant growth and photosynthetic activities. The fragments of slippers and running shoes boosted plant growth but changed the flavonoid content and photosynthetic factors. Trekking shoe sole fragments did not exhibit plant photoinhibition; however, their leachate inhibited photosynthesis. Overall, it was concluded that shoe sole fragments can cause adverse effects in plants and impair soil environment. Our study findings indicate that it is necessary to develop shoe soles that have less harmful environmental effects.


Asunto(s)
Microplásticos , Vigna , Ecosistema , Estrés Oxidativo , Plásticos , Zapatos , Suelo
12.
J Hazard Mater ; 421: 126779, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34352528

RESUMEN

This study investigated the toxic effects of leachates from microplastic fragments of soles from four different types of shoes (slippers, trekking shoes, running shoes, and sneakers) on three aquatic organisms (Chlamydomonas reinhardtii, Daphnia magna, and Danio rerio). The chemical components in each leachate were identified; furthermore, chlorophyll a contents of C. reinhardtii were measured, and immobilization of D. magna and deformities in D. rerio were observed. The abnormalities observed in the test species exposed to the leachates were compared and chemical compounds majorly influencing the species were determined by principal component analysis (PCA). Sneaker leachate showed growth inhibitions in C. reinhardtii, immobility and mortality in D. magna, and severe abnormalities in D. rerio. Consequently, aquatic toxicity was majorly associated with benzothiazole, carbon disulfide, ethyl acetate, and p-xylene. The results showed that toxic chemicals could leach from load-originated microplastics when exposed to aquatic media, and consequently, induce significant negative effects on aquatic organisms. Since microplastics from shoe soles discharge the above-mentioned toxic chemicals, regulating the chemical use during plastic production is critical to prevent severe effects of microplastic toxicity in aquatic organisms, and to maintain the health of aquatic environments.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Organismos Acuáticos , Clorofila A , Daphnia , Agua Dulce , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
13.
Children (Basel) ; 8(6)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204551

RESUMEN

This study was designed to establish safe guidelines for pediatric dental practice regarding temporomandibular joint (TMJ) range of motion (ROM) and mouth area (MA). A total of 438 children aged 3-15 years old of homogenous ethnicity participated in the study; the distribution of participants was approximately equal (sex; n = 15; age, n = 30). Maximum mouth opening (MMO), body height, weight, and age of each participant were recorded, and the TMJ ROM including anterior and lateral movements, MA, and mouth width were documented. Males showed higher mouth width, MMO, and MA values than females. MMO and MA increased with age, height, and weight in a statistically significant manner. MMO of 40 mm is reached by the age of 5.2 years, at a height of 105.9 cm and a weight of 18.6 kg. MMO showed a moderate correlation with age, height, weight, and mouth width, and MA moderately correlated with mouth width. Anterior and lateral movements did not show any close relation to these aforementioned factors. The findings of this study suggest that forcible mouth opening over 40 mm should be more cautiously considered, especially in children shorter than 105 cm, lighter than 18 kg and in children under 5 years old.

14.
Aquat Toxicol ; 237: 105900, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34166955

RESUMEN

Globally, perovskite solar cells (PSCs) represent a third-generation photovoltaic technology that is being increasingly implemented and commercialized. However, the biological impacts of leachates from PSCs are poorly understood. Therefore, the aim of this study was to investigate the ecotoxicity of PSC leachates compared with that of commercial Si-based solar cell (SBSC) leachates. We performed leaching assessments and aquatic bioassays using internationally recommended test species and measured and compared the ecotoxicity of PSC and SBSC leachates. As a result of the leaching analyses, Si, Pb, and Al were found to be the most leached elements from broken PSCs and SBSCs. The bioassays indicated that polycrystalline SBSC (p-Si) and monocrystalline SBSC (m-Si) leachates were more toxic to fish embryos than the PSC leachates and that water fleas were sensitive to m-Si leachates, but less sensitive to PSC and p-Si leachates. In addition, principle component analyses indicated that the ecotoxicity of solar cell leachates was related to either the Pb or Si content. This is the first comparative study of the potential ecotoxicity of PSC and SBSC leachates in aquatic ecosystems, and the results of which can be used in the environmentally safe commercialization of solar cells.


Asunto(s)
Ecosistema , Contaminantes Químicos del Agua , Animales , Compuestos de Calcio , Óxidos , Silicio , Titanio , Contaminantes Químicos del Agua/toxicidad
15.
J Oncol ; 2020: 4659062, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32411236

RESUMEN

Successful identification and targeting of oncogenic gene fusion is a major breakthrough in cancer treatment. Here, we investigate the therapeutic implications and feasibility of using a targeted RNA sequencing panel to identify fusion genes in gastrointestinal and rare cancers. From February through December 2017, patients with gastrointestinal, hepatobiliary, gynecologic, sarcoma, or rare cancers were recruited for a clinical sequencing project at Samsung Medical Center (NCT #02593578). The median age of the patients was 58 years (range, 31-81 years), and the male-to-female ratio was 1.3 : 1. A total of 118 patients passed the quality control process for a next-generation sequencing- (NGS-) based targeted sequencing assay. The NGS-based targeted sequencing assay was performed to detect gene fusions in 36-53 cancer-implicated genes. The following cancer types were included in this study: 28 colorectal cancers, 27 biliary tract cancers, 25 gastric cancers, 18 soft tissue sarcomas, 9 pancreatic cancers, 6 ovarian cancers, and 9 other rare cancers. Strong fusion was detected in 25 samples (21.2%). We found that 5.9% (7/118) of patients had known targetable fusion genes involving NTRK1 (n=3), FGFR (n=3), and RET (n=1), and 10.2% (12/118) of patients had potentially targetable fusion genes involving RAF1 (n=4), BRAF (n=2), ALK (n=2), ROS1 (n=1), EGFR (n=1), and CLDN18 (n=2). Thus, we successfully identified a substantial proportion of patients harboring fusion genes by RNA panel sequencing of gastrointestinal/rare cancers. Targetable and potentially targetable involved fusion genes were NTRK1, RET, FGFR3, FGFR2, BRAF, RAF1, ALK, ROS1, and CLDN18. Detection of fusion genes by RNA panel sequencing may be beneficial in refractory patients with gastrointestinal/rare cancers.

16.
J Hazard Mater ; 382: 121150, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31561195

RESUMEN

Perfluorooctanoic acid (PFOA) is one of the persistent organic pollutants that has been listed in Annex A of the Stockholm Convention and has attracted attention owing to its endocrine-disrupting properties. However, there is currently little information available regarding the soil ecotoxicity of PFOA and the associated ecological risks. Accordingly, in this study, we sought to assess the soil ecological risk of PFOA based on a probabilistic approach using data obtained from multispecies bioassays and soil toxicity assessments, from which we generated soil species sensitivity distributions and estimated soil protective concentrations for PFOA. Using the latter distributions, we also undertook a probabilistic ecological risk assessment. On the basis of acute and chronic toxicity estimates obtained from bioassays involving eight soil-associated organisms from six diverse taxonomic groups, we could deduce that PFOA poses a negligible risk to soil ecosystems. However, we also found that this chemical may be more toxic than some of the established endocrine-disrupting chemicals such as bisphenol A, nonylphenol, and methylparaben, thereby indicating that further in-depth studies would be necessary to obtain a better understanding of the toxic potential of this chemical in the soil environment.


Asunto(s)
Caprilatos/toxicidad , Fluorocarburos/toxicidad , Contaminantes del Suelo/toxicidad , Animales , Artrópodos/efectos de los fármacos , Bioensayo , Caenorhabditis elegans/efectos de los fármacos , Oligoquetos/efectos de los fármacos , Desarrollo de la Planta/efectos de los fármacos , Plantas/efectos de los fármacos , Medición de Riesgo
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