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Operative Dentistry Jan 2021The literature reviewed suggests that airborne particle abrasion has no negative effects on the bond strength of resin-based materials to dentin and that a positive... (Meta-Analysis)
Meta-Analysis
CLINICAL RELEVANCE
The literature reviewed suggests that airborne particle abrasion has no negative effects on the bond strength of resin-based materials to dentin and that a positive influence on dentin bond strength was only achieved in specific air-abrasion conditions.
SUMMARY
In this systematic review the authors investigated how airborne-particle abrasion (APA) using aluminum oxide affects the bond strength of resin-based materials to dentin. The search was performed in three databases. In vitro studies (Type of study) comparing the bond strength of resin-based materials (Outcome) to air-abraded (Intervention) compared with non-air-abraded (Comparison) human dentin (Population) were included (the PICOT elements are given parenthetically). From 5437 unique articles, 65 were read in full, 33 were included in the qualitative synthesis, and 32 were included in the meta-analysis. Methodologic quality and risk of bias were assessed. Comparisons were performed between air-abraded and control dentin groups by adopting a random-effects model (α=0.05). Additional analyses were carried out for the different parameters used in APA: type of surface treatment in the control group, particle size, air pressure, and APA duration. The bond strength to air-abraded dentin was favored only when the control surface was treated with a hand excavator. For particle size, APA was favored when the particle size was >30 μm and the controls were no treatment or hand excavator or when the particle size was ≤30 μm and the control was bur. In addition, the results favored air-abraded groups only when the pressure was > 5 bar and bur was used in the control group. No significant differences were observed for duration of APA. No comparison on bond strength considering the presence of aging conditions was possible in the included studies due to the low number of studies that aged the specimens. In conclusion, APA had no negative effects on the bond strength of resin-based materials to dentin and was able to improve the dentin bond strength only when the particle size was > 30 μm and air pressure was > 5 bar. PROSPERO registration protocol: CRD42018096128.
Topics: Aged; Aluminum Oxide; Composite Resins; Dental Bonding; Dentin; Humans; Materials Testing; Resin Cements; Shear Strength; Surface Properties
PubMed: 32926155
DOI: 10.2341/19-216-L -
Current Environmental Health Reports Jun 2023Despite increasing awareness of the ubiquity of microplastics (MPs) in our environments, little is known about their risk of developmental toxicity. Even less is known... (Review)
Review
PURPOSE OF REVIEW
Despite increasing awareness of the ubiquity of microplastics (MPs) in our environments, little is known about their risk of developmental toxicity. Even less is known about the environmental distribution and associated toxicity of nanoplastics (NPs). Here, we review the current literature on the capacity for MPs and NPs to be transported across the placental barrier and the potential to exert toxicity on the developing fetus.
RECENT FINDINGS
This review includes 11 research articles covering in vitro, in vivo, and ex vivo models, and observational studies. The current literature confirms the placental translocation of MPs and NPs, depending on physicochemical properties such as size, charge, and chemical modification as well as protein corona formation. Specific transport mechanisms for translocation remain unclear. There is emerging evidence of placental and fetal toxicity due to plastic particles based on animal and in vitro studies. Nine out of eleven studies examined in this review found that plastic particles were capable of placental translocation. In the future, more studies are needed to confirm and quantify the existence of MPs and NPs in human placentas. Additionally, translocation of different plastic particle types and heterogenous mixtures across the placenta, exposure at different periods of gestation, and associations with adverse birth and other developmental outcomes should also be investigated.
Topics: Animals; Pregnancy; Female; Humans; Placenta; Plastics; Microplastics; Water Pollutants, Chemical
PubMed: 36848019
DOI: 10.1007/s40572-023-00391-x -
Biomolecules Aug 2023Following previously published systematic reviews on the diagnostic use of nanoparticles (NPs), in this manuscript, we report published methods for radiolabeling... (Review)
Review
Following previously published systematic reviews on the diagnostic use of nanoparticles (NPs), in this manuscript, we report published methods for radiolabeling nanoparticles with therapeutic alpha-emitting, beta-emitting, or Auger's electron-emitting isotopes. After analyzing 234 papers, we found that different methods were used with the same isotope and the same type of nanoparticle. The most common type of nanoparticles used are the PLGA and PAMAM nanoparticles, and the most commonly used therapeutic isotope is Lu. Regarding labeling methods, the direct encapsulation of the isotope resulted in the most reliable and reproducible technique. Radiolabeled nanoparticles show promising results in metastatic breast and lung cancer, although this field of research needs more clinical studies, mainly on the comparison of nanoparticles with chemotherapy.
Topics: Dendrimers; Isotope Labeling; Nanomedicine; Nanoparticles; Radioisotopes
PubMed: 37627307
DOI: 10.3390/biom13081241 -
Plant Physiology and Biochemistry : PPB Nov 2023Microplastics (MPx) and nanoplastics (NPx) are increasingly accumulating in terrestrial ecosystems, heightening concerns about their potential adverse effects on human... (Review)
Review
Microplastics (MPx) and nanoplastics (NPx) are increasingly accumulating in terrestrial ecosystems, heightening concerns about their potential adverse effects on human health via the food chain. Techniques aimed at recovering the most challenging colloidal fractions of MPx and NPx, especially for analytical purposes, are limited. This systematic review emphasises the absence of a universal, efficient, and cost-effective analytical method as the primary hindrance to studying MPx and NPx in soil and plant samples. The study reveals that several methods, including density separation, organic matter removal, and filtration, are utilized to detect MPx or NPx in soil through vibrational spectroscopy and visual identification. Instruments such as Pyrolysis Gas Chromatography Mass Spectrometry (Py-GCMS), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) Spectroscopy, and fluorescence microscopy are employed to identify MPx and NPx in plant tissue. In extraction procedures, organic solvents and sonication are used to isolate NPx from plant tissues, while Pyrolysis GC-MS quantifies the plastics. SEM and TEM serve to observe and characterize NPx within plant tissues. Additionally, FTIR and fluorescence microscopy are utilized to identify polymers of MPx and NPx based on their spectral characteristics and fluorescence signals. The findings from this review clarify the identification and quantification methods for MPx and NPx in soil and plant systems and provide a comprehensive methodology for assessing MPx/NPx in the environment.
Topics: Humans; Microplastics; Plastics; Soil; Ecosystem; Polymers; Water Pollutants, Chemical
PubMed: 37918078
DOI: 10.1016/j.plaphy.2023.108132 -
Supportive Care in Cancer : Official... Mar 2023This systematic review and meta-analysis aimed to evaluate the efficacy of barrier films and dressings in preventing acute radiation dermatitis (RD). (Meta-Analysis)
Meta-Analysis Review
PURPOSE
This systematic review and meta-analysis aimed to evaluate the efficacy of barrier films and dressings in preventing acute radiation dermatitis (RD).
METHODS
OVID Medline, Embase, and Cochrane databases were searched from 1946 to September 2020 to identify randomized controlled trials on the use of barrier films or dressings to prevent RD. For comparable outcomes between studies, pooled effect sizes and 95% confidence intervals (CI) were calculated using the random effects analysis in RevMan 5.4.
RESULTS
Fourteen and 11 studies were included in the qualitative and quantitative analyses, respectively. Five types of barrier films used for RD were identified: Hydrofilm, StrataXRT®, Mepitel® Film, 3 M™ Cavilon™ No-Sting Barrier Film, and silver leaf nylon dressing. Hydrofilm and Mepitel Film significantly reduced the development of RD grade ≥ 2 in breast and head and neck cancer patients (RR 0.32, 95%CI 0.19, 0.56, p < 0.0001; RR 0.21, 95%CI 0.05, 0.89, p = 0.03, resp.). Moreover, Hydrofilm had a beneficial effect on patient-reported outcomes (PROs) (SMD -0.75, 95%CI -1.2, -0.29, p = 0.001). The meta-analyses on the other barrier films did not show any significant effect.
CONCLUSION
This review and meta-analysis demonstrated that Hydrofilm and Mepitel Film could effectively reduce RD severity and improve PROs. The evidence is generally weak for all the studies on barrier films and dressings due to a limited study number, high risk of bias, small sample sizes, and minimal comparable outcome measures. It's potential has been proven, but future research in this field is recommended to confirm the efficacy of these products and assess real-world feasibility.
Topics: Humans; Bandages; Silicones; Breast; Dermatitis
PubMed: 36929087
DOI: 10.1007/s00520-023-07671-0 -
Environmental Pollution (Barking, Essex... Dec 2022The dispersion of microplastics (MPs) in coastal and marine environments and their potential harmful effects on organisms and ecosystems makes MPs pollution an emerging... (Review)
Review
The dispersion of microplastics (MPs) in coastal and marine environments and their potential harmful effects on organisms and ecosystems makes MPs pollution an emerging problem that has gained increasing attention from the scientific community. Despite the recent increase in the number of studies on MPs presence in different marine environments, investigations in Latin America and the Caribbean (LAC) are still relatively limited. This review presents the spatial distribution (where) and the methods applied (how) in assessing MPs contamination on LAC sandy beaches, identifying the challenges to be faced in advancing the understanding of this emerging contaminant. Most of the 39 papers reviewed were published between 2020 and 2021 (51%) and conducted on Brazilian beaches (43%). The LAC investigations apply spot sampling (69%) on shoreline stretches between 10 and 1000 km (59%). These works used inconsistent sampling methods, incomparable techniques for MPs extraction from sediments, and different measurement units to report their data. The MPs presence on LAC beaches is not negligible, as it varies significantly in its distribution and concentration (0-2457 MP/dw kg and 0-5458 MP/m). Its highest accumulation is on ocean island beaches; however, there are still large stretches of coastline (Cuba, Venezuela, Argentina) with no data on MPs presence and a small number of studies exploring these contaminants' temporal variability. The lack of standardization in the studies' methodologies, particularly their measurement units, hinders their quantitative comparison and our ability to establish baseline values regarding MPs abundance on LAC beaches. In this sense, future works should direct efforts towards the spatial and temporal expansion of their sampling, as well as protocol standardization to facilitate result comparability on MPs on LAC sandy beaches.
Topics: Microplastics; Plastics; Ecosystem; Latin America; Environmental Monitoring; Water Pollutants, Chemical; Caribbean Region; Geologic Sediments
PubMed: 36152712
DOI: 10.1016/j.envpol.2022.120231 -
International Journal of Biological... Apr 2023Levan is a homopolysaccharide of fructose that has both scientific and industrial importance, with various applications in health, pharmaceutical, cosmetic and food... (Review)
Review
Levan is a homopolysaccharide of fructose that has both scientific and industrial importance, with various applications in health, pharmaceutical, cosmetic and food industries. Despite its broad spectrum of uses, there are only a limited number of commercial levan sources due to the high costs related to its production. To make production economically viable, efforts have been concentrated on the selection of levan-producing microorganisms, the genetic manipulation of new strains, and the use of inexpensive agro-industrial byproducts as substrates. Another efficient strategy involves the concomitant synthesis of other products with high market value and as such, the successful co-production of levan was demonstrated with fructooligosaccharides, ethanol, sorbitol, poly-ε-lysine, poly-γ-glutamic acid and polyhydroxyalkanoates. This paper offers a systematic review of important aspects regarding recent strategies involving the simultaneous synthesis of levan and other bioproducts of aggregate value reported to date and discusses the challenges and opportunities for its large-scale production and applications.
Topics: Polyhydroxyalkanoates; Ethanol; Fructose; Fructans; Food Industry
PubMed: 36828085
DOI: 10.1016/j.ijbiomac.2023.123800 -
Journal of Neurosurgery. Spine Oct 2023By minimizing imaging artifact and particle scatter, carbon fiber-reinforced polyetheretherketone (CF-PEEK) spinal implants are hypothesized to enhance radiotherapy (RT)...
OBJECTIVE
By minimizing imaging artifact and particle scatter, carbon fiber-reinforced polyetheretherketone (CF-PEEK) spinal implants are hypothesized to enhance radiotherapy (RT) planning/dosing and improve oncological outcomes. However, robust clinical studies comparing tumor surgery outcomes between CF-PEEK and traditional metallic implants are lacking. In this paper, the authors performed a systematic review of the literature with the aim to describe clinical outcomes in patients with spine tumors who received CF-PEEK implants, focusing on implant-related complications and oncological outcomes.
METHODS
A systematic review of the literature published between database inception and May 2022 was performed in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The PubMed database was queried using the terms "carbon fiber" and "spine" or "spinal." The inclusion criteria were articles that described patients with CF-PEEK pedicle screw fixation and had a minimum of 5 patients. Case reports and phantom studies were excluded.
RESULTS
This review included 11 articles with 326 patients (237 with CF-PEEK-based implants and 89 with titanium-based implants). The mean follow-up period was 13.5 months, and most tumors were metastatic (67.1%). The rates of implant-related complications in the CF-PEEK and titanium groups were 7.8% and 4.7%, respectively. The rate of pedicle screw fracture was 1.7% in the CF-PEEK group and 2.4% in the titanium group. The rates of reoperation were 5.7% (with 60.0% because of implant failure or junctional kyphosis) and 4.8% (all because of implant failure or junctional kyphosis) in the CF-PEEK and titanium groups, respectively. When reported, 72.5% of patients received postoperative RT (41.0% stereotactic body RT, 30.8% fractionated RT, 25.6% proton, 2.6% carbon ion). Four articles suggested that implant artifact was reduced in the CF-PEEK group. Local recurrence occurred in 14.4% of CF-PEEK and 10.7% of titanium-implanted patients.
CONCLUSIONS
While CF-PEEK harbors similar implant failure rates to traditional metallic implants with reduced imaging artifact, it remains unclear whether CF-PEEK implants improve oncological outcomes. This study highlights the need for prospective, direct comparative clinical studies.
Topics: Humans; Carbon Fiber; Titanium; Prospective Studies; Polyethylene Glycols; Ketones; Carbon; Pedicle Screws; Postoperative Complications; Neoplasms; Kyphosis
PubMed: 37382293
DOI: 10.3171/2023.5.SPINE23106 -
The Journal of Craniofacial SurgeryEar reconstruction is 1 of the most technically challenging sub-specialties of craniofacial and reconstructive plastic surgery. The reconstructive ear must not only... (Review)
Review
Ear reconstruction is 1 of the most technically challenging sub-specialties of craniofacial and reconstructive plastic surgery. The reconstructive ear must not only fulfil the requirement of being aesthetically pleasing but must also have good vascularity with a low complication rate. Several ear reconstructive techniques have been developed such as the autologous ear reconstruction technique using costal cartilage and ear reconstruction with high-density porous polyethylene or Medpor (Porex Surgical, Inc, College Park, GA). Autologous ear reconstructive techniques have advantages of durability and low infection rates however are associated with poorer aesthetic outcomes such as poor projection of the ear. Medpor has advantages of a more consistent three-dimensional definition without the need to harvest costochondral cartilage and create a donor site. However, due to its alloplastic material properties, Medpor has historically been reported as having a higher rate of extrusion and infection. This is the first systematic review to compare the outcomes of both techniques. The 6 studies that were reviewed were analyzed against 3 evaluative criteria: aesthetic outcome, complication rate, and convenience of intervention. This is so a comprehensive, evidence-based decision can be made by the surgeon and patient when ear reconstruction is required. The results showed heterogeneity in data and a lack of detailed descriptions of the assessment for aesthetic outcomes and convenience, hence were inconclusive. The results however showed that there were more complications with Medpor framework with 15% of total cases resulting in either extrusion or infection compared to 2% of autologous ear reconstruction framework.
Topics: Ear, External; Esthetics, Dental; Humans; Polyethylene; Polyethylenes; Plastic Surgery Procedures
PubMed: 34643598
DOI: 10.1097/SCS.0000000000008130 -
Cells Oct 2022This systematic review aimed to analyze the development and functionality of microfluidic concentration gradient generators (CGGs) for toxicological evaluation of... (Review)
Review
This systematic review aimed to analyze the development and functionality of microfluidic concentration gradient generators (CGGs) for toxicological evaluation of different biological organisms. We searched articles using the keywords: concentration gradient generator, toxicity, and microfluidic device. Only 33 of the 352 articles found were included and examined regarding the fabrication of the microdevices, the characteristics of the CGG, the biological model, and the desired results. The main fabrication method was soft lithography, using polydimethylsiloxane (PDMS) material (91%) and SU-8 as the mold (58.3%). New technologies were applied to minimize shear and bubble problems, reduce costs, and accelerate prototyping. The Christmas tree CGG design and its variations were the most reported in the studies, as well as the convective method of generation (61%). Biological models included bacteria and nematodes for antibiotic screening, microalgae for pollutant toxicity, tumor and normal cells for, primarily, chemotherapy screening, and Zebrafish embryos for drug and metal developmental toxicity. The toxic effects of each concentration generated were evaluated mostly with imaging and microscopy techniques. This study showed an advantage of CGGs over other techniques and their applicability for several biological models. Even with soft lithography, PDMS, and Christmas tree being more popular in their respective categories, current studies aim to apply new technologies and intricate architectures to improve testing effectiveness and reduce common microfluidics problems, allowing for high applicability of toxicity tests in different medical and environmental models.
Topics: Animals; Anti-Bacterial Agents; Dimethylpolysiloxanes; Environmental Pollutants; Lab-On-A-Chip Devices; Zebrafish
PubMed: 36231063
DOI: 10.3390/cells11193101