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The Science of the Total Environment Dec 2022This systematic review aims to summarize the current knowledge on biological effects of micro- and nanoplastics (MNPs) on human health based on mammalian systems. An...
This systematic review aims to summarize the current knowledge on biological effects of micro- and nanoplastics (MNPs) on human health based on mammalian systems. An extensive search of the literature led to a total of 133 primary research articles on the health relevance of MNPs. Our findings revealed that although the study of MNP cytotoxicity and inflammatory response represents a major research theme, most studies (105 articles) focused on the effects of polystyrene MNPs due to their wide availability as a well characterised research material that can be manufactured with a large range of particle sizes, fluorescence labelling as well as various surface modifications. Among the 133 studies covered in this review, 117 articles reported adverse health effects after being exposed to MNPs. Mammalian in vitro studies identified multiple biological effects including cytotoxicity, oxidative stress, inflammatory response, genotoxicity, embryotoxicity, hepatotoxicity, neurotoxicity, renal toxicity and even carcinogenicity, while rodent in vivo models confirmed the bioaccumulation of MNPs in the liver, spleen, kidney, brain, lung and gut, presenting adverse effects at different levels including reproductive toxic effects and trans-generational toxicity. In contrast, the remaining 16 studies indicated an insignificant impact of MNPs on humans. A few studies attempted to investigate the mechanisms or factors driving the toxicity of MNPs and identified several determining factors including size, concentration, shape, surface charge, attached pollutants and weathering process, which, however, were not benchmarked or considered by most studies. This review demonstrates that there are still many inconsistencies in the evaluation of the potential health effects of MNPs due to the lack of comparability between studies. Current limitations hindering the attainment of reproducible conclusions as well as recommendations for future research directions are also presented.
Topics: Animals; Humans; Environmental Pollutants; Mammals; Microplastics; Particle Size; Plastics; Polystyrenes
PubMed: 35987230
DOI: 10.1016/j.scitotenv.2022.158111 -
Operative Dentistry Nov 2021The following PICO (Patient/Population, Intervention, Comparison, and Outcomes) question was proposed: "Are retention rates of composite resin restorations in noncarious... (Meta-Analysis)
Meta-Analysis
PURPOSE
The following PICO (Patient/Population, Intervention, Comparison, and Outcomes) question was proposed: "Are retention rates of composite resin restorations in noncarious cervical lesions (NCCLs) when using adhesives considered "gold standard" (OptiBond FL and Clearfil SE Bond) higher than those obtained with other adhesives brands"?
METHODS
A search was performed in February 2019 (updated in November 2019) in the PubMed/MEDLINE, EMBASE, LILACS, BBO, Web of Science, Cochrane Library, Grey Literature, and IADR abstracts (1990-2018); unpublished and ongoing trial registries, dissertations, and theses were also searched. Only randomized clinical trials (RCTs) conducted in NCCLs that compared either OptiBond FL or Clearfil SE Bond adhesive with other commercially available adhesives were included. The risk of bias (RoB) was applied by using the Cochrane Collaboration tool. A meta-analysis was performed for retention rates at different follow-up times using a random effects model for both the adhesives. Heterogeneity was assessed with the Cochran Q test and I2 statistics. Grading of Recommendations: Assessment, Development and Evaluation (GRADE) assessed the quality of evidence.
RESULTS
After removal of duplicates and noneligible articles, 25 studies remained for qualitative synthesis, as one study was common to the two adhesives, of which 9 studies were used for the OptiBond FL meta-analysis and 14 for the Clearfil SE Bond meta-analysis. No significant differences were observed for retention rates in follow-up periods of 12-24 months (p=0.97), 36-48 months (p=0.72), or 108-156 months (p=0.73) for OptiBond FL; and for 12-24 months (p=0.10) and 36-48 months (p=0.17) for Clearfil SE Bond. A significant difference was only found for OptiBond FL at 60-96 months (p=0.02), but only three studies were included in this meta-analysis.
CONCLUSIONS
The evidence from available RCTs conducted in NCCLs that compared OptiBond FL or Clearfil SE Bond does not support the widespread concept that these adhesives are better than any other competitive brands available in the dental market.
Topics: Composite Resins; Dental Bonding; Dental Cements; Dental Restoration, Permanent; Dentin-Bonding Agents; Humans; Resin Cements
PubMed: 34919728
DOI: 10.2341/20-059-LIT -
BMC Oral Health Aug 2023Large cavity designs and access cavities impair endodontically treated tooth fracture resistance. As the tooth's strength is known to reduce significantly after the root...
BACKGROUND
Large cavity designs and access cavities impair endodontically treated tooth fracture resistance. As the tooth's strength is known to reduce significantly after the root canal treatment, occlusal loading as a result of functions such as chewing, biting and certain parafunctional tendencies makes the endodontically treated tooth vulnerable to fracture. Hence, after endodontic treatment, it is vital to give adequate and appropriate restorative material to avoid tooth fractures. Accordingly, the choice of such restorative material should be dictated by the property of fracture resistance.
OBJECTIVE
The goal of this study was to conduct a systematic review and critical analysis of available data from in vitro studies examining the fracture resistance of endodontically treated posterior teeth restored with fiber-reinforced composites.
METHODOLOGY
The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRIS-MA) Statement was used to guide the reporting of this systematic review A comprehensive literature search was performed using MEDLINE (via PubMed), Scopus, ScienceDirect, Google Scholar, and LILACS. A manual search of the reference lists of the articles was also performed. The databases provided a total of 796 studies from the electronic systematic search. The databases provided a total of 796 studies from the electronic systematic search. Two reviewers scrutinized the papers for eligibility based on inclusion/exclusion criteria and extracted data. The studies were assessed for their potential risk of bias. Based on modified JBI & CRIS (checklist for reporting in vitro studies) guidelines, along with the methodology and treatment objective, we have formulated 13 parameters specifically to assess the risk of bias. A total of 18 studies met the inclusion criteria and were included for qualitative analysis. Considering the high heterogeneity of the studies included, a meta-analysis could not be performed.
RESULTS
The majority of the included studies had a moderate or high risk of bias. When compared to traditional hybrid composites, fiber-reinforced composites showed increased fracture resistance of endodontically treated teeth in the majority of investigations. On the other hand, limited evidence was found for the bulk fill composites. Moreover, moderate evidence was found for the fracture resistance of inlays and fiber posts with fiber-reinforced composites for core build-up in endodontically treated teeth. No evidence could be found comparing the fracture resistance of endo crowns and fiber-reinforced composites in endodontically treated teeth.
CONCLUSION
According to the research, using fiber-reinforced composites instead of conventional hybrid composites improves the fracture resistance of endodontically treated teeth. However, there was a high risk of bias in the research considered. No judgments could be reached about the superiority of one material over another based-on comparisons between other core restorations.
Topics: Humans; Tooth, Nonvital; Dental Materials; Crowns; Tooth Fractures; Composite Resins; Dental Stress Analysis
PubMed: 37574536
DOI: 10.1186/s12903-023-03217-2 -
The Cochrane Database of Systematic... Jun 2020Hyperkalaemia is a common electrolyte abnormality caused by reduced renal potassium excretion in patients with chronic kidney diseases (CKD). Potassium binders, such as... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Hyperkalaemia is a common electrolyte abnormality caused by reduced renal potassium excretion in patients with chronic kidney diseases (CKD). Potassium binders, such as sodium polystyrene sulfonate and calcium polystyrene sulfonate, are widely used but may lead to constipation and other adverse gastrointestinal (GI) symptoms, reducing their tolerability. Patiromer and sodium zirconium cyclosilicate are newer ion exchange resins for treatment of hyperkalaemia which may cause fewer GI side-effects. Although more recent studies are focusing on clinically-relevant endpoints such as cardiac complications or death, the evidence on safety is still limited. Given the recent expansion in the available treatment options, it is appropriate to review the evidence of effectiveness and tolerability of all potassium exchange resins among people with CKD, with the aim to provide guidance to consumers, practitioners, and policy-makers.
OBJECTIVES
To assess the benefits and harms of potassium binders for treating chronic hyperkalaemia among adults and children with CKD.
SEARCH METHODS
We searched the Cochrane Kidney and Transplant Register of Studies up to 10 March 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.
SELECTION CRITERIA
Randomised controlled trials (RCTs) and quasi-randomised controlled studies (quasi-RCTs) evaluating potassium binders for chronic hyperkalaemia administered in adults and children with CKD.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed risks of bias and extracted data. Treatment estimates were summarised by random effects meta-analysis and expressed as relative risk (RR) or mean difference (MD), with 95% confidence interval (CI). Evidence certainty was assessed using GRADE processes.
MAIN RESULTS
Fifteen studies, randomising 1849 adult participants were eligible for inclusion. Twelve studies involved participants with CKD (stages 1 to 5) not requiring dialysis and three studies were among participants treated with haemodialysis. Potassium binders included calcium polystyrene sulfonate, sodium polystyrene sulfonate, patiromer, and sodium zirconium cyclosilicate. A range of routes, doses, and timing of drug administration were used. Study duration varied from 12 hours to 52 weeks (median 4 weeks). Three were cross-over studies. The mean study age ranged from 53.1 years to 73 years. No studies evaluated treatment in children. Some studies had methodological domains that were at high or unclear risks of bias, leading to low certainty in the results. Studies were not designed to measure treatment effects on cardiac arrhythmias or major GI symptoms. Ten studies (1367 randomised participants) compared a potassium binder to placebo. The certainty of the evidence was low for all outcomes. We categorised treatments in newer agents (patiromer or sodium zirconium cyclosilicate) and older agents (calcium polystyrene sulfonate and sodium polystyrene sulfonate). Patiromer or sodium zirconium cyclosilicate may make little or no difference to death (any cause) (4 studies, 688 participants: RR 0.69, 95% CI 0.11, 4.32; I = 0%; low certainty evidence) in CKD. The treatment effect of older potassium binders on death (any cause) was unknown. One cardiovascular death was reported with potassium binder in one study, showing that there was no difference between patiromer or sodium zirconium cyclosilicate and placebo for cardiovascular death in CKD and HD. There was no evidence of a difference between patiromer or sodium zirconium cyclosilicate and placebo for health-related quality of life (HRQoL) at the end of treatment (one study) in CKD or HD. Potassium binders had uncertain effects on nausea (3 studies, 229 participants: RR 2.10, 95% CI 0.65, 6.78; I = 0%; low certainty evidence), diarrhoea (5 studies, 720 participants: RR 0.84, 95% CI 0.47, 1.48; I = 0%; low certainty evidence), and vomiting (2 studies, 122 participants: RR 1.72, 95% CI 0.35 to 8.51; I = 0%; low certainty evidence) in CKD. Potassium binders may lower serum potassium levels (at the end of treatment) (3 studies, 277 participants: MD -0.62 mEq/L, 95% CI -0.97, -0.27; I = 92%; low certainty evidence) in CKD and HD. Potassium binders had uncertain effects on constipation (4 studies, 425 participants: RR 1.58, 95% CI 0.71, 3.52; I = 0%; low certainty evidence) in CKD. Potassium binders may decrease systolic blood pressure (BP) (2 studies, 369 participants: MD -3.73 mmHg, 95%CI -6.64 to -0.83; I = 79%; low certainty evidence) and diastolic BP (one study) at the end of the treatment. No study reported outcome data for cardiac arrhythmias or major GI events. Calcium polystyrene sulfonate may make little or no difference to serum potassium levels at end of treatment, compared to sodium polystyrene sulfonate (2 studies, 117 participants: MD 0.38 mEq/L, 95% CI -0.03 to 0.79; I = 42%, low certainty evidence). There was no evidence of a difference in systolic BP (one study), diastolic BP (one study), or constipation (one study) between calcium polystyrene sulfonate and sodium polystyrene sulfonate. There was no difference between high-dose and low-dose patiromer for death (sudden death) (one study), stroke (one study), myocardial infarction (one study), or constipation (one study). The comparative effects whether potassium binders were administered with or without food, laxatives, or sorbitol, were very uncertain with insufficient data to perform meta-analysis.
AUTHORS' CONCLUSIONS
Evidence supporting clinical decision-making for different potassium binders to treat chronic hyperkalaemia in adults with CKD is of low certainty; no studies were identified in children. Available studies have not been designed to measure treatment effects on clinical outcomes such as cardiac arrhythmias or major GI symptoms. This review suggests the need for a large, adequately powered study of potassium binders versus placebo that assesses clinical outcomes of relevance to patients, clinicians and policy-makers. This data could be used to assess cost-effectiveness, given the lack of definitive studies and the clinical importance of potassium binders for chronic hyperkalaemia in people with CKD.
Topics: Aged; Cause of Death; Chelating Agents; Chelation Therapy; Chronic Disease; Humans; Hyperkalemia; Middle Aged; Polymers; Polystyrenes; Potassium; Quality of Life; Randomized Controlled Trials as Topic; Renal Insufficiency, Chronic; Silicates
PubMed: 32588430
DOI: 10.1002/14651858.CD013165.pub2 -
European Journal of Clinical... Mar 2020Inulin, consisting of repetitive fructosyl units linked by β(2,1) bonds, is a readily fermentable fiber by intestinal bacteria that generates large quantities of... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Inulin, consisting of repetitive fructosyl units linked by β(2,1) bonds, is a readily fermentable fiber by intestinal bacteria that generates large quantities of short-chain fatty acids (SCFA). In individuals with constipation, it was reported that inulin ingestion was associated with a significant increase in stool frequency, suggesting a potential impact of inulin on human gut microbiota composition. Progress in high-throughput technologies allow assessment of human-associated microbiomes in terms of diversity and taxonomic or functional composition, and can identify changes in response to a specific supplementation. Hence, to understand the effects of inulin on the human gut microbiome is pivotal to gain insight into their mechanisms of action.
METHODS
Here, we conducted a systematic review of human studies in adult individuals showing the effects of inulin on the gut microbiome. We searched in MEDLINE, EMBASE, Web of Science, and Scopus databases for articles in English published in peer-reviewed journals and indexed up until March 2019. We used multiple search terms capturing gut microbiome, gut microflora, intestinal microbiota, intestinal flora, gut microbiota, gut flora, microbial gut community, gut microbial composition, and inulin.
RESULTS
Overall, nine original articles reported the effects of inulin on microbiome composition in adult humans, most of them being randomized, double-blind, placebo-controlled trials (n = 7). Studies varied significantly in design (3 studies associated inulin and oligofructose), supplementation protocols (from 5 to 20 gr per day of inulin consumed) and in microbiome assessment methods (16S sequencing, n = 7). The most consistent change was an increase in Bifidobacterium. Other concordant results included an increase in relative abundance of Anaerostipes, Faecalibacterium, and Lactobacillus, and a decrease in relative abundance of Bacteroides after inulin supplementation.
CONCLUSIONS
Our systematic review assessed the evidence for the effects of inulin supplementation on the human gut microbiome. However, these in vivo studies did not confirm in vitro experiments as the taxonomic alterations were not associated with increase in short-chain fatty acids levels.
Topics: Clinical Studies as Topic; Dietary Supplements; Gastrointestinal Microbiome; Humans; Inulin; Microbiota
PubMed: 31707507
DOI: 10.1007/s10096-019-03721-w -
Nanotechnology Mar 2023Metal-organic frameworks (MOFs), as a class of promising material with adjustable function and controllable structure, have been widely used in the food industry,... (Review)
Review
Metal-organic frameworks (MOFs), as a class of promising material with adjustable function and controllable structure, have been widely used in the food industry, chemical industry, biological medicine, and sensors. Biomacromolecules and living systems play a critical role in the world. However, the insufficiency in stability, recyclability, and efficiency, significantly impedes their further utilization in slightly harsh conditions. MOF-bio-interface engineering effectively address the above-mentioned shortages of biomacromolecules and living systems, and thereby attracting considerable attentions. Herein, we systematically review the achievements in the area of MOF-bio-interface. In particular, we summarize the interface between MOFs and proteins (enzymes and non-enzymatic proteins), polysaccharides, DNA, cells, microbes, and viruses. Meanwhile, we discuss the limitations of this approach and propose future research directions. We expect that this review could provide new insights and inspire new research efforts towards life science and material science.
Topics: Metal-Organic Frameworks
PubMed: 36796094
DOI: 10.1088/1361-6528/acbc81 -
Environmental Pollution (Barking, Essex... Apr 2023Because of the high production rates, low recycling rates, and poor waste management of plastics, an increasing amount of plastic is entering the aquatic environment,... (Review)
Review
Because of the high production rates, low recycling rates, and poor waste management of plastics, an increasing amount of plastic is entering the aquatic environment, where it can provide new ecological niches for microbial communities and form a so-called plastisphere. Recent studies have focused on the one-way impact of plastic substrata or biofilm communities. However, our understanding of the two-way interactions between plastics and biofilms is still limited. This review first summarizes the formation process and the co-occurrence network analysis of the aquatic plastisphere to comprehensively illustrate the succession pattern of biofilm communities and the potential consistency between keystone taxa and specific environmental behavior of the plastisphere. Furthermore, this review sheds light on mutual interactions between plastics and biofilms. Plastic properties, environmental conditions, and colonization time affect biofilm development. Meanwhile, the biofilm communities, in turn, influence the environmental behaviors of plastics, including transport, contaminant accumulation, and especially the fragmentation and degradation of plastics. Based on a systematic literature review and cross-referencing from these disciplines, the current research focus, and future challenges in exploring aquatic plastisphere development and biofilm-plastic interactions are proposed.
Topics: Plastics; Bacteria; Biofilms; Microbiota
PubMed: 36736560
DOI: 10.1016/j.envpol.2023.121196 -
Journal of Materials Chemistry. B Apr 2023Materials research relating to bio-based polymers and composites has become the order of the day and several types of research are being undertaken on these materials.... (Review)
Review
Materials research relating to bio-based polymers and composites has become the order of the day and several types of research are being undertaken on these materials. This is mainly due to the belief in the ability of these polymers and composites to serve as potential alternatives for synthetic polymers and fiber-reinforced composites and to mitigate problems pertaining to environmental pollution. A majority of synthetic fibers and polymers in the market today are developed from nonrenewable petroleum-based materials. These have the potential to harm the natural biodiversity of the environment. On the other hand, the use of bioplastics and biocomposites is supported by a few facts such as low cost, lesser energy consumption during production, and notable mechanical and thermal characteristics. The usage of bio-based fibers and polymers in the manufacture of biocomposites in numerous applications greatly enhance the sustainability by eradicating the problem of waste generation. Considering all the above points, the current review focuses on the synthesis and characterization of bioplastics and biocomposites. An elaborate discussion on the mechanical and thermal properties of these materials has also been made. In addition, this review comprehensively discusses the applications, challenges, and prospects of bioplastics and biocomposites.
Topics: Biopolymers; Polymers
PubMed: 36971198
DOI: 10.1039/d2tb02221d -
The Journal of Evidence-based Dental... Dec 2023The aim of this systematic review was to evaluate the survival and complication rates of resin composite laminate veneers. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The aim of this systematic review was to evaluate the survival and complication rates of resin composite laminate veneers.
METHODS
Randomized controlled trials and cohort studies with a minimum 2-year follow-up assessing survival and complication rates of resin composite laminate veneers on permanent dentition from 1998 to May 2022. Literature searches were conducted in MEDLINE (PubMed), Scopus, and the Cochrane Central Register of Controlled Trials electronic databases. References cited in the related reviews and included full-text articles were also hand-searched to further identify potentially relevant studies.
RESULTS
A total of 827 articles were identified. Twenty-two studies were considered for full-text review after the title and abstract screening stage. After exclusion, 7 studies (3 randomized controlled trials and 4 cohort studies) were included in the systematic review. Three published scales were adopted for the quality and risk of bias assessment. At the survival rate threshold, the overall heterogeneity (I) for randomized controlled trials was 50.5% (P = .108). The overall pooled survival rate of the randomized controlled trials was 88% (95% CI: 81%-94%), with the mean follow-up time ranging from 24 to 97 months. Surface roughness, color mismatch, and marginal discoloration were the most reported complications.
CONCLUSION
Resin composite laminate veneers demonstrated moderately high survival rates for the entire sample and the direct laminate veneer group demonstrated higher survival rates than the indirect approach. Most of the complications were regarded as clinically acceptable with or without reintervention.
Topics: Humans; Dental Porcelain; Composite Resins; Dental Restoration Failure
PubMed: 38035903
DOI: 10.1016/j.jebdp.2023.101911 -
Molecules (Basel, Switzerland) Mar 2020Chitosan derivatives, and more specifically, glycosylated derivatives, are nowadays attracting much attention within the scientific community due to the fact that this... (Review)
Review
Chitosan derivatives, and more specifically, glycosylated derivatives, are nowadays attracting much attention within the scientific community due to the fact that this set of engineered polysaccharides finds application in different sectors, spanning from food to the biomedical field. Overcoming chitosan (physical) limitations or grafting biological relevant molecules, to mention a few, represent two cardinal strategies to modify parent biopolymer; thereby, synthetizing high added value polysaccharides. The present review is focused on the introduction of oligosaccharide side chains on the backbone of chitosan. The synthetic aspects and the effect on physical-chemical properties of such modifications are discussed. Finally, examples of potential applications in biomaterials design and drug delivery of these novel modified chitosans are disclosed.
Topics: Animals; Biocompatible Materials; Chitosan; Drug Delivery Systems; Glycosylation; Humans; Molecular Dynamics Simulation; Nanoparticles; Oligosaccharides; Tissue Engineering
PubMed: 32230971
DOI: 10.3390/molecules25071534