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Journal of Exposure Science &... Mar 2024Humans are likely exposed to microplastics (MPs) in a variety of places including indoor and outdoor air. Research to better understand how exposure to MPs correlates to...
BACKGROUND
Humans are likely exposed to microplastics (MPs) in a variety of places including indoor and outdoor air. Research to better understand how exposure to MPs correlates to health is growing. To fully understand the possible impacts of MPs on human health, it is necessary to quantify MP exposure and identify what critical data gaps exist.
OBJECTIVES
The current paper provides a human exposure assessment of microplastics in the air using systematically reviewed literature that provided concentration of MPs in air as well as doses used in toxicology studies to calculate inhalation exposure dose.
METHODS
All published peer-reviewed journal articles, non-published papers, and grey literature that focused on micro- or nano-plastics in indoor and outdoor air were systematically searched using PRISMA guidelines. Literature that defined specific concentrations and size of MPs in air or exposed to human lung cells, animals, or humans with measurable health impacts were included in data extraction. Inhalational exposures were calculated for different age groups using published MP concentrations from the included literature using exposure dose equations and values from U.S. ATSDR and EPA.
RESULTS
Calculated mean indoor inhalational exposures from passive sampling methods were higher than those calculated from active sampling methods. When comparing indoor and outdoor sampling, calculated inhalation exposures from indoor samples were greater than those from outdoor samples. Inhalation exposures of MPs differed between age groups with infants having the highest calculated dose values for all locations followed by preschool age children, middle-school aged children, pregnant women, adolescents, and non-pregnant adults. MP doses used in toxicology studies produced higher calculated mean inhalational exposures than those from environmental samples.
IMPACT
This study is the first known systematic review of inhalational MP exposure from indoor and outdoor air. It also provides inhalational exposures calculated from previously published environmental samples of MPs as well as from toxicology studies.
Topics: Adolescent; Adult; Animals; Child; Child, Preschool; Female; Humans; Infant; Male; Young Adult; Air Pollutants; Air Pollution, Indoor; Environmental Monitoring; Inhalation Exposure; Microplastics; Risk Assessment
PubMed: 38184724
DOI: 10.1038/s41370-023-00634-x -
The Science of the Total Environment Feb 2023Microplastics (<5 mm) (MPs) are widely distributed throughout the world, and their accumulation and migration in the environment have caused health and safety concerns.... (Review)
Review
Microplastics (<5 mm) (MPs) are widely distributed throughout the world, and their accumulation and migration in the environment have caused health and safety concerns. Currently, most of the reviewed literatures mainly focus on the distribution in various environmental media, adsorption mechanisms with different pollutants, and characterization of MPs. Therefore, the present review mainly highlights the characterization techniques of MPs and the underlying mechanisms of their combination with conventional coexisting substances (heavy metals, organic pollutants, and nutrients). We observed that massive MP pollution has been found in many areas, especially in Africa, Asia, India, South Africa, North America and Europe. The separation methods of MPs in different environmental media are basically similar, including sampling, pre-treatment, flotation, filtration and digestion. The combination of multiple characterization technologies can more precisely identify the shape, abundance, colour, and particle size of MPs. Notably, although recent reports have confirmed that MPs can act as carriers of heavy metals and carry them into organisms to cause harm, MPs have different adsorption and desorption characteristics for various heavy metals. The adsorption capacity of organic pollutants onto MPs is closely related to their hydrophobicity, specific surface area and functional group characteristics. The relative abundance of MPs in sediments and lakes had a significantly positive correlation with the mass concentration of total nitrogen in lake water, but this finding still needs to be further verified. Based on current research, we suggest that future MP research should focus on characterization technology, environmental migration, ecological effects, health risks and degradation methods.
Topics: Microplastics; Plastics; Environmental Pollutants; Water Pollutants, Chemical; Metals, Heavy; South Africa
PubMed: 36423843
DOI: 10.1016/j.scitotenv.2022.160151 -
The Journal of Prosthetic Dentistry Oct 2021The best protocol to restore endodontically treated teeth is still unclear, with many factors to be considered, including the selection and necessity of a post, the... (Review)
Review
STATEMENT OF PROBLEM
The best protocol to restore endodontically treated teeth is still unclear, with many factors to be considered, including the selection and necessity of a post, the type of coronal restoration, the amount of remaining coronal structure, and the type of luting agent.
PURPOSE
The purpose of this systematic review was to assess the restorative preferences for endodontically treated teeth between dentists and dental students.
MATERIAL AND METHODS
Survey studies, written in English, of dentists and dental students, which evaluated the use of intracanal posts and other restorative options for endodontically treated teeth, were selected. Searches were performed in the PubMed and SCOPUS databases without time restriction. Screening and data extraction were performed by 2 researchers independently. A standardized outline was used to extract the data (questions related to the theme and the response rate of each question on the survey), and the risk of bias was assessed. Descriptive analysis was performed of the collected information.
RESULTS
Twenty-five articles were included. Most dentists who answered the surveys reported the time since graduation as 1 to 20 years (40%), and 44% were specialists. The most reported choices concerning the type of posts used were prefabricated posts (45.8%), cast metal posts (16.7%), and both posts (16.7%). The cast metal posts were cited more frequently in surveys published between 1994 and 2010, whereas prefabricated posts, both metal and glass fiber ones, were cited between 2006 and 2019. The preferred luting agent for intracanal posts was resin-based (47%). These choices seem to have been influenced by time and by the level of postgraduate training.
CONCLUSIONS
Restorative preferences related to posts have changed over time, from the use of cast posts to prefabricated ones or the use of both posts and seem to be influenced by experience and postgraduate training.
Topics: Composite Resins; Crowns; Dentists; Humans; Post and Core Technique; Students; Tooth, Nonvital
PubMed: 32981715
DOI: 10.1016/j.prosdent.2020.07.005 -
Chemosphere Nov 2021Although the toxicity of microplastics (MPs) and nanoplastics (NPs) is recognized at different trophic levels, our know-how about their effects on amphibians is limited.... (Review)
Review
Although the toxicity of microplastics (MPs) and nanoplastics (NPs) is recognized at different trophic levels, our know-how about their effects on amphibians is limited. Thus, we present and discuss the current state on studies involving amphibians and plastic particles, based on a broad approach to studies published in the last 5 years. To search for the articles, the ISI Web of Science, ScienceDirect, and Scopus databases were consulted, using different descriptors related to the topic of study. After the systematic search, we identified 848 publications. Of these, 12 studies addressed the relationship "plastic particles and amphibians" (7 studies developed in the laboratory and 5 field studies). The scientometric analysis points to geographic concentration of studies in Brazil and China; low investment in research in the area, and limited participation of international authors in the studies carried out. In the systematic approach, we confirm the scarcity of available data on the toxicity of plastic particles in amphibians; we observed a concentration of studies in the Anura order, only one study explored the toxicological effects of NPs and polystyrene and polyethylene are the most studied plastic types. Moreover, the laboratory tested concentrations are distant from those of the environmentally relevant; and little is known about the mechanisms of action of NPs/MPs involved in the identified (eco)toxicological effects. Thus, we strongly recommend more investments in this area, given the ubiquitous nature of NPs/MPs in aquatic environments and their possible consequences on the dynamics, reproduction, and survival of species in the natural environment.
Topics: Animals; Anura; Microplastics; Plastics; Risk Factors; Water Pollutants, Chemical
PubMed: 34153909
DOI: 10.1016/j.chemosphere.2021.131090 -
BMC Gastroenterology Jul 2023This study was performed to compare a metal stent (MS) and plastic stent (PS) in terms of efficacy and complications during neoadjuvant therapy (NAT) and the... (Meta-Analysis)
Meta-Analysis
Comparison of metal versus plastic stent for preoperative biliary drainage in patients with pancreatic cancer undergoing neoadjuvant therapy: a meta-analysis and systematic review.
BACKGROUND
This study was performed to compare a metal stent (MS) and plastic stent (PS) in terms of efficacy and complications during neoadjuvant therapy (NAT) and the perioperative period.
METHODS
We performed an electronic search of the following databases until 1 June 2022: PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov. Studies comparing an MS versus PS for PBD in patients with pancreatic cancer undergoing NAT were included.
RESULTS
The meta-analysis showed that use of an MS was associated with lower rates of reintervention (p < 0.00001), delay of NAT (p = 0.007), recurrent biliary obstruction (RBO) (p = 0.003), and cholangitis (p = 0.03). There were no significant differences between the two groups in terms of stent migration (p = 0.31), postoperative complications (p = 0.20), leakage (p = 0.90), and R0 resection (p = 0.50).
CONCLUSIONS
Use of an MS for PBD in patients with pancreatic cancer undergoing NAT followed by surgery was associated with lower rates of reintervention, delay of NAT, RBO, and cholangitis compared with use of a PS. However, the postoperative outcomes were comparable between the MS and PS. Further studies on this topic are recommended.
Topics: Humans; Neoadjuvant Therapy; Drainage; Pancreatic Neoplasms; Metals; Stents; Cholangitis; Cholestasis; Plastics
PubMed: 37438761
DOI: 10.1186/s12876-023-02874-5 -
The Science of the Total Environment Jan 2024Micro/nanoplastics are emerging agricultural pollutants globally. Micro/nanoplastics can adhere to terrestrial plant surfaces, be absorbed and transported by plants, and... (Review)
Review
Micro/nanoplastics are emerging agricultural pollutants globally. Micro/nanoplastics can adhere to terrestrial plant surfaces, be absorbed and transported by plants, and accumulate in the edible parts of plants, leading to the possibility of enrichment and transmission through the food chain and threatening human health. However, the underlying mechanism remains unclear. With increased studies on the internalization of micro/nanoplastics in terrestrial plants, a comprehensive and systematic review summarizing the current research trends and progress is warranted to provide a reference for further relevant research. Based on bibliometric analysis, this study focused on the mechanisms, study methods, and reduction techniques of micro/nanoplastics adherence, uptake, and translocation by terrestrial plants. The results showed that micro/nanoplastics can adhere to the surfaces of plant tissues such as seeds, roots, and leaves. Root uptake (root-to-leaf translocation) and foliar uptake (leaf-to-root translocation) are the two simultaneous internalization pathways of MNPs in plants. The observation methods included scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS), and inductively coupled plasma-mass spectrometry (ICP-MS). We highlighted the necessity and urgency of reducing the uptake and translocation of MNPs by plants and found that the application of silicon may be a promising approach for reducing internalization. This study identifies current knowledge gaps and proposes possible future needs.
Topics: Humans; Microplastics; Plants; Bibliometrics
PubMed: 37848143
DOI: 10.1016/j.scitotenv.2023.167786 -
The Journal of Adhesive Dentistry 2018This study systematically reviewed the literature to compare the bonding ability of dental adhesives applied to sound dentin (SoD) vs caries-affected dentin (CAD). (Meta-Analysis)
Meta-Analysis
PURPOSE
This study systematically reviewed the literature to compare the bonding ability of dental adhesives applied to sound dentin (SoD) vs caries-affected dentin (CAD).
MATERIALS AND METHODS
Three international databases (Medline/PubMed, Scopus, and Web of Science) were searched. Eligible studies which evaluated the bond strength to both SoD and CAD were included. Random effects meta-analyses were conducted to calculate pooled mean difference between substrates, separately for etch-and-rinse and self-etch adhesives. Subgroup analyses were carried out to explore heterogeneity considering the methods used for removal of infected carious dentin. A comparison between etch-and-rinse and self-etch adhesives restricted to CAD was also performed. Statistical heterogeneity was considered using the I2 test. The risk of bias of all included studies was assessed.
RESULTS
In total, 2260 articles were found, 65 were selected for full-text reading, and 40 studies were included. The meta-analyses favored SoD over CAD for both etch-and-rinse (effect size: -10.04; 95% confidence interval [CI]: -11.94, -8.14; I2 = 95%) and self-etch adhesives (effect size: -6.76; 95% CI: -8.23, -5.30; I2 = 89%). In the subgroup analyses, SoD was favored irrespective of the method used for caries removal (effect size ≤ -4.86; I2 ≥ 28%): excavation (manual or with burs), grinding with abrasive papers, combination of more than one method, and when the method was not mentioned. The meta-analysis restricted to CAD favored etch-and-rinse over self-etch adhesives (effect size: 3.13; 95% CI: 1.82, 4.44; I2 = 72%). Most included studies were judged as having an unclear risk of bias.
CONCLUSION
Bonding to SoD yields better results compared to CAD. Etch-and-rinse adhesives performed better than self-etch adhesives when applied to CAD.
Topics: Dental Bonding; Dental Caries; Dental Cements; Dental Pulp Cavity; Dentin; Dentin-Bonding Agents; Humans; Resin Cements; Tensile Strength
PubMed: 29399679
DOI: 10.3290/j.jad.a39775 -
The International Journal of... Dec 2023To identify the most effective protocol for bonding denture bases and artificial teeth made with different computer-aided design and manufacturing (CAD/CAM) materials... (Meta-Analysis)
Meta-Analysis
PURPOSE
To identify the most effective protocol for bonding denture bases and artificial teeth made with different computer-aided design and manufacturing (CAD/CAM) materials (milled and 3D-printed) and conventional heat-polymerized resins.
MATERIALS AND METHODS
This review was performed according to the Preferred Reporting Items for Systematic and Meta-Analysis (PRISMA) criteria and registered in the International Prospective Registry of Systematic Reviews PROSPERO (CRD42021276084). An electronic search was performed independently by two examiners in PubMed/MEDLINE, Cochrane Library, Scopus, Web of Science, ProQuest, and OpenGrey databases for articles published up to and including December 2021.
RESULTS
The electronic search returned 806 articles, and after duplicates were removed, 589 articles remained. Four articles met the eligibility criteria to be included in this study. After evaluating the different combinations of denture base materials and artificial teeth, it was found that IvoBase CAD Bond (Ivoclar Vivadent) was effective for bonding CAD/CAM denture bases to prefabricated acrylic resin teeth, which showed no differences compared to the heat-polymerized resin denture base bonded to prefabricated acrylic resin teeth (χ2: 68.56; I2: 96%; P < .001).
CONCLUSIONS
The IvoBase CAD Bond bonding system can be used for the fabrication of CAD/CAM denture bases with prefabricated acrylic resin teeth.
Topics: Acrylic Resins; Computer-Aided Design; Dental Bonding; Denture Bases; Materials Testing; Surface Properties; Tooth, Artificial
PubMed: 38109398
DOI: 10.11607/ijp.8062 -
Journal of Indian Prosthodontic Society 2021This systematic review with meta-analysis aimed to evaluate the effect of the laser treatment on bond strength between Y-TZP and the resin cement or with the veneering... (Meta-Analysis)
Meta-Analysis Review
AIM
This systematic review with meta-analysis aimed to evaluate the effect of the laser treatment on bond strength between Y-TZP and the resin cement or with the veneering ceramic, and the effect on the alteration of the Y-TZP surface roughness.
SETTINGS AND DESIGN
Systematic review and meta analysis following PROSPERO guidelines.
MATERIALS AND METHODS
A comprehensive review was performed up to September 2020 on four databases (PubMed/MEDLINE, Embase, Scopus, and Cochrane Library), using the combination of keywords: "laser AND zirconia AND surface treatment AND bond strength".
STATISTICAL ANALYSIS USED
The meta-analysis was based on the Mantel-Haenszel and inverse variance methods. The continuous outcome was evaluated by mean difference and the corresponding 95% confidence intervals.
RESULTS
A total of 37 studies were identified for the inclusion of data, with only in vitro studies. The types of laser reported in the studies were: Er:YAG, Nd:YAG, Er,Cr:YSGG, CO2, Femtosecond, and Yb lasers. A random-effect model found statistically significant differences between lasers and control groups of Y-TZP (P < 0.00001; MD: 3.08; 95% CI: 2.58 to 3.58). Only the bond strength with the Er:YAG laser did not present statistical difference (P = 0.51; MD: 0.22; 95% CI: -0.44-0.88). In another analysis, a random-effect model found a statistically significant difference between the laser and control groups on surface roughness (P < 0.00001; MD: 0.96; 95% CI: 0.86 to 1.06).
CONCLUSIONS
Laser irradiation is capable to improve the Y-TZP surface roughness and the bond strength of zirconia with resin cement and veneering ceramics. However, there is a lack of laser protocol for the zirconia surface, a fact that makes a simple and direct comparison difficult.
Topics: Ceramics; Humans; Lasers, Solid-State; Materials Testing; Microscopy, Electron, Scanning; Resin Cements; Shear Strength; Surface Properties; Yttrium; Zirconium
PubMed: 33938862
DOI: 10.4103/jips.jips_590_20 -
International Journal of Pharmaceutics Feb 2014The purpose of this study was to investigate the evaluation of the biomedical effectiveness of poly(amido)amine dendrimers generation 4.0 (PAMAM G4) as a drug and as... (Meta-Analysis)
Meta-Analysis Review
The purpose of this study was to investigate the evaluation of the biomedical effectiveness of poly(amido)amine dendrimers generation 4.0 (PAMAM G4) as a drug and as drug carriers by a systematic review of literature and meta-analysis. The results obtained from meta-analysis concluded that drug therapy reduces the change of parameters in relation to the control. The impact of the drug administered to change the test parameters are dependent on the type of tissue. PAMAM G4 may be effective in vitro and in vivo as a drug and drug carriers and may have appropriate applications in various fields of medicine. PAMAM G4 dendrimers hold promises for nanomedicine.
Topics: Animals; Dendrimers; Drug Carriers; Humans; Nanomedicine; Nylons
PubMed: 24374222
DOI: 10.1016/j.ijpharm.2013.12.033