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Frontiers in Pediatrics 2022Mechanistic studies show that heavy metals interfere with the hematopoietic system by inhibiting key enzymes, which could lead to anemia. However, the link between...
BACKGROUND
Mechanistic studies show that heavy metals interfere with the hematopoietic system by inhibiting key enzymes, which could lead to anemia. However, the link between children's exposure and red blood cell (RBC) parameters has been inconsistent. We aimed to summarize evidence on human studies exploring the association between exposure to lead, mercury, cadmium, arsenic, and chromium VI and RBC parameters in children.
METHODS
Following the PRISMA guidelines, we searched PubMed, Scopus, and Web of Science databases for studies published between January 2010 and April 2022. Eligible papers included human observational studies that directly assessed exposure (internal dose) to the heavy metals under study and RBC parameters in participants aged ≤ 18 years. We excluded studies using hospital-based samples. Study quality was assessed using the National Institutes of Health's Quality Assessment Tools for Cohort and Cross-Sectional Studies. We synthesized the evidence using vote counting based on the direction of the relationship.
RESULTS
Out of 6,652 retrieved papers, we included a total of 38 (33 assessing lead, four mercury, two cadmium, and two arsenic; chromium VI was not assessed in any included paper). More than half of the studies were conducted in Asia. We found evidence of a positive relationship between lead concentration and hemoglobin (proportion of studies reporting negative relationships = 0.750; 95% Confidence Interval (CI) 0.583, 0.874) and mean corpuscular hemoglobin (0.875; 95% CI 0.546, 0.986), and a positive relationship with red cell distribution width (0.000; 95%CI 0.000, 0.379). When considering only good-quality studies (24% of the Pb studies), only the relationship with hemoglobin levels remained (0.875; 95% CI: 0.546, 0.986).
CONCLUSION
We found evidence of a negative relationship between lead concentration and hemoglobin and mean corpuscular hemoglobin and of a positive relationship with red cell distribution width in children. We also identified a need to conduct more studies in European countries. Future studies should use standardized practices and make efforts to increase study quality, namely by conducting comprehensive longitudinal studies. Our findings support the need to take further actions to limit heavy metal exposure during childhood.
PubMed: 36275050
DOI: 10.3389/fped.2022.921239 -
Materials (Basel, Switzerland) Apr 2021The aim of this study was to confirm the hypothesis that patients with one or more amalgam restorations have an increased risk for systemic diseases rather than patients... (Review)
Review
OBJECTIVE
The aim of this study was to confirm the hypothesis that patients with one or more amalgam restorations have an increased risk for systemic diseases rather than patients with resin-based restorations.
DATA
The data search produced an initial 3568 total number of records. All titles and abstract were reviewed by five independent examiners, and only 36 records were selected for full text in depth examination. Out of these, only nine publications matched the inclusion criteria and were included in this systematic review.
SOURCES
Electronic databases (MEDLINE, Scopus, Embase, and Web of Knowledge) were searched up to June 2019. In addition, a manual search was carried out on journals related to this topic.
STUDY SELECTION
All selected human clinical studies compared patients with dental amalgam restorations to patients with non-amalgam restorations on restorative material related diseases/health conditions with at least 50 patients and a reasonable follow up. The systemic effects of dental restorations were analyzed. As for any systemic effects, there was no difference between amalgam and composite restoration.
CONCLUSIONS
With the limitations of the few available randomized controlled trials (RCTs) on the matter, amalgam restorations, similarly to other modern resin-based materials, were not related to an increased risk of systemic diseases or conditions.
CLINICAL SIGNIFICANCE
On the basis of the available RCTs, amalgam restorations, if compared with resin-based fillings, do not show an increased risk for systemic diseases. There is still insufficient evidence to exclude or demonstrate any direct influence on general health. The removal of old amalgam restorations and their substitution with more modern adhesive restorations should be performed only when clinically necessary and not just for material concerns. In order to better evaluate the safety of dental amalgam compared to other more modern restorative materials, further RCTs that consider important parameters such as long and uniform follow up periods, number of restorations per patient, and sample populations representative of chronic or degenerative diseases are needed.
PubMed: 33920968
DOI: 10.3390/ma14081980 -
Pharmacological Research Jul 2024Nonalcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease worldwide. Epidemiological studies have reported that exposure of the... (Meta-Analysis)
Meta-Analysis Review
Nonalcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease worldwide. Epidemiological studies have reported that exposure of the population to environmental endocrine-disrupting chemicals (EDCs) is associated with NAFLD. However, EDCs are of different types, and there are inconsistencies in the relevant evidence and descriptions, which have not been systematically summarized so far. Therefore, this study aimed to determine the association between population exposure to EDCs and NAFLD. Three databases, including PubMed, Web of science, and Embase were searched, and 27 articles were included in this study. Methodological quality, heterogeneity, and publication bias of the included studies were assessed using the Newcastle-Ottawa scale, I statistics, Begg's test, and Egger's test. The estimated effect sizes of the included studies were pooled and evaluated using the random-effects model (I > 50 %) and the fixed-effects model ( I < 50 %). The pooled-estimate effect sizes showed that population exposure to Phthalates (PAEs) (OR = 1.18, 95 % CI:1.03-1.34), cadmium (Cd) (OR = 1.37, 95 % CI:1.09-1.72), and bisphenol A (OR = 1.43, 95 % CI:1.24-1.65) were positively correlated with the risk of NAFLD. Exposure to mercury (OR =1.46, 95 % CI:1.17-1.84) and Cd increased the risk of "elevated alanine aminotransferase". On the contrary, no significant association was identified between perfluoroalkyl substances (OR =0.99, 95 % CI:0.93-1.06) and NAFLD. However, female exposure to perfluorooctanoic acid (OR =1.82, 95 % CI:1.01-3.26) led to a higher risk of NAFLD than male exposure. In conclusion, this study revealed that EDCs were risk factors for NAFLD. Nonetheless, the sensitivity analysis results of some of the meta-analyses were not stable and demonstrated high heterogeneity. The evidence for these associations is limited, and more large-scale population-based studies are required to confirm these findings.
Topics: Non-alcoholic Fatty Liver Disease; Humans; Endocrine Disruptors; Phthalic Acids; Environmental Pollutants; Phenols; Benzhydryl Compounds; Cadmium; Fluorocarbons
PubMed: 38862070
DOI: 10.1016/j.phrs.2024.107251 -
Environmental Monitoring and Assessment Aug 2022Mercury (Hg) mobilization and accumulation in the environment is directly related to forest fires. Biomass burning accounts for about 13% of the total contribution of Hg...
Mercury (Hg) mobilization and accumulation in the environment is directly related to forest fires. Biomass burning accounts for about 13% of the total contribution of Hg from natural sources. The aim of this work is to contribute to the knowledge of how wildfires modify mercury compounds behaviour and the effects it has in the Hg cycle, based on a systematic bibliographic review and analysis. Systems dynamics is an adequate focus to analyze the mobilization of Hg due to wildfires, which meets all the requirements to be studied by multimedia modelling. The development and application for the first time of a dynamic multimedia model of Hg taking into account specifically the influences of wildfires is one of the novelties of this work. Different scenarios show that an increase in the number of fires will consequently increase the mercury emitted into the atmosphere, modifying its natural cycle, producing a long-term modification of Hg compositions and concentrations in the different media. Hg movement caused by wildfires can cause complications in living beings and alter the ecosystems. This study found that the Hg soil content could as well be an indicator to measure the impact of fire on the environment. This model can also be generalized to conduct additional studies under comparable conditions, helping to understand the importance of forest fires in global Hg cycles.
Topics: Ecosystem; Environmental Monitoring; Fires; Forests; Mercury; Wildfires
PubMed: 36002668
DOI: 10.1007/s10661-022-10208-3 -
International Journal of Dentistry 2020A systematic literature search was conducted in four electronic databases (Ovid via PubMed, Web of Science, Scopus, and CENTRAL) including all available randomised... (Review)
Review
METHODS
A systematic literature search was conducted in four electronic databases (Ovid via PubMed, Web of Science, Scopus, and CENTRAL) including all available randomised controlled trials published in the last 15 years comparing the use of dental amalgam with composite resins in humans with a follow-up period of at least one year. The primary outcome was the Hg concentration in biological fluids (urine, hair, blood, and saliva) with the aim of assessing their reliability as biomarkers of Hg exposure. The risk of bias was assessed through the Cochrane Collaboration tool and the overall quality of evidence through the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system. The results of the meta-analysis were expressed using a random-effects model, and their power was assessed through the trial sequential analysis (TSA).
RESULTS
From the initial 2555 results, only 6 publications were included in the review: five were considered as having high risk of bias, whereas one as having moderate risk. Only two articles were eligible for quantitative analysis. The meta-analysis gathered data from 859 patients but was nevertheless not significant ( = 0.12). The TSA confirmed this evidence revealing that it was due to a lack of statistical power since the required information size (RIS) threshold is not reached.
CONCLUSIONS
The existing evidence revealed that there are not enough data to support the hypothesis that restorations with dental amalgam can cause nephrotoxicity when compared with composite resins restorations.
PubMed: 32849873
DOI: 10.1155/2020/8857238 -
Eco-Environment & Health Dec 2022Research about farmland pollution by heavy metals/metalloids in China has drawn growing attention. However, there was rare information on spatiotemporal evolution and...
Research about farmland pollution by heavy metals/metalloids in China has drawn growing attention. However, there was rare information on spatiotemporal evolution and pollution levels of heavy metals in the major grain-producing areas. We extracted and examined data from 276 publications between 2010 and 2021 covering five major grain-producing regions in China from 2010 to 2021. Spatiotemporal evolution characteristics of main heavy metals/metalloids was obtained by meta-analysis. In addition, subgroup analyses were carried out to study preliminary correlations related to accumulation of the pollutants. Cadmium (Cd) was found to be the most prevailing pollutant in the regions in terms of both spatial distribution and temporal accumulation. The Huang-Huai-Hai Plain was the most severely polluted. Accumulation of Cd, mercury (Hg) and copper (Cu) increased from 2010 to 2015 when compared with the 1990 background data. Further, the levels of five key heavy metals (Cd, Cu, Hg, lead [Pb] and zinc [Zn]) showed increasing trends from 2016 to 2021 in all five regions. Soil pH and mean annual precipitation had variable influences on heavy metal accumulation. Alkaline soil and areas with less rainfall faced higher pollution levels. Farmlands cropped with mixed species showed smaller effect sizes of heavy metals than those with single upland crop, suggesting that mixed farmland use patterns could alleviate the levels of heavy metals in soil. Of various soil remediation efforts, farmland projects only held a small market share. The findings are important to support the research of risk assessment, regulatory development, pollution prevention, fund allocation and remediation actions.
PubMed: 38077260
DOI: 10.1016/j.eehl.2022.10.004 -
Internal and Emergency Medicine Jun 2021Not much is known about how accurate and reproducible different thermometers are at diagnosing patients with suspected fever. The study aims at evaluating which... (Meta-Analysis)
Meta-Analysis
Not much is known about how accurate and reproducible different thermometers are at diagnosing patients with suspected fever. The study aims at evaluating which peripheral thermometers are more accurate and reproducible. We searched Medline, Embase, Scopus, WOS, CENTRAL, and Cinahl to perform: (1) diagnostic accuracy meta-analysis (MA) using rectal mercury-in-glass or digital thermometry as reference, and bivariate models for pooling; (2) network MA to estimate differences in mean temperature between devices; (3) Bland-Altman method to estimate 95% coefficient of reproducibility. PROSPERO registration: CRD42020174996. We included 46 studies enrolling more than 12,000 patients. Using 38 °C (100.4 ℉) as cut-off temperature, temporal infrared thermometry had a sensitivity of 0.76 (95% confidence interval, 0.65, 0.84; low certainty) and specificity of 0.96 (0.92, 0.98; moderate certainty); tympanic infrared thermometry had a sensitivity of 0.77 (0.60, 0.88; low certainty) and specificity of 0.98 (0.95, 0.99; moderate certainty). For all the other index devices, it was not possible to pool the estimates. Compared to the rectal mercury-in-glass thermometer, mean temperature differences were not statistically different from zero for temporal or tympanic infrared thermometry; the median coefficient of reproducibility ranged between 0.53 °C [0.95 ℉] for infrared temporal and 1.2 °C [2.16 ℉] for axillary digital thermometry. Several peripheral thermometers proved specific, but not sensitive for diagnosing fever with rectal thermometry as a reference standard, meaning that finding a temperature below 38 °C does not rule out fever. Fixed differences between temperatures together with random error means facing differences between measurements in the order of 2 °C [4.5 ℉]. This study informs practitioners of the limitations associated with different thermometers; peripheral ones are specific but not sensitive.
Topics: Body Temperature; Diagnostic Tests, Routine; Equipment Design; Humans; Reproducibility of Results; Sensitivity and Specificity; Thermometers
PubMed: 33237494
DOI: 10.1007/s11739-020-02556-0 -
Journal of Pharmaceutical Policy and... Jun 2023Heart failure is an ever-growing contributor to morbidity and mortality in the ageing population. Medication adherence rates among the HF population vary widely in the... (Review)
Review
BACKGROUND
Heart failure is an ever-growing contributor to morbidity and mortality in the ageing population. Medication adherence rates among the HF population vary widely in the literature, with a reported range of 10-98%. Technologies have been developed to improve adherence to therapies and other clinical outcomes.
AIMS
This systematic review aims to investigate the effect of different technologies on medication adherence in patients with heart failure. It also aims to determine their impact on other clinical outcomes and examine the potential of these technologies in clinical practice.
METHODS
This systematic review was conducted using the following databases: PubMed Central UK, Embase, MEDLINE, CINAHL Plus, PsycINFO and Cochrane Library until October 2022. Studies were included if they were randomised controlled trials that used technology to improve medication adherence as an outcome in heart failure patients. The Cochrane Collaboration's Risk of Bias tool was used to assess individual studies. This review was registered with PROSPERO (ID: CRD42022371865).
RESULTS
A total of nine studies met the inclusion criteria. Two studies showed statistically significant improvement in medication adherence following their respective interventions. Eight studies had at least one statistically significant result in the other clinical outcomes it measured, including self-care, quality of life and hospitalisations. All studies that evaluated self-care management showed statistically significant improvement. Improvements in other outcomes, such as quality of life and hospitalisations, were inconsistent.
CONCLUSION
It is observable that there is limited evidence for using technology to improve medication adherence in heart failure patients. Further studies with larger study populations and validated self-reporting methods for medication adherence are required.
PubMed: 37386604
DOI: 10.1186/s40545-023-00582-9 -
Ecotoxicology and Environmental Safety Jan 2021Traditional Chinese medicine has become an important pillar of "Healthy China" and the national medical system in recent years. Due to the wide range of raw materials in...
Traditional Chinese medicine has become an important pillar of "Healthy China" and the national medical system in recent years. Due to the wide range of raw materials in traditional Chinese medicinal materials (TCMM), the issue of metals has attracted more and more attention. In this paper, a comprehensive review of public reports on metals in TCMM in recent decades was conducted. From a total of 1969 reported articles, a total of 296 research reports on metals in TCMM were screened. The 296 reports involved 255 species in 85 families, with a total of 274 medicinal materials. These TCMM were divided into taproot-type, leaf-type, flower and fruit-type, herba-type, stem-type and bark-type medicinal materials according to the medicinal parts. The content of five metals lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr) in these TCMM was noted, and the distribution rules for metals were analyzed. The results showed that: (1) For the distribution of metals in different medicinal parts, Pb was mainly distributed in leaves; Cd was mainly distributed in flowers and fruits, stems and leaves; Hg was mainly distributed in barks; As was mainly distributed in stems; Cr was mainly distributed in stems, flowers and fruits. (2) The areas with the highest risk of metal residues were the Qinghai-Tibet Plateau, south China, and southwest China. (3) Among all types of TCMM, herba-type medicinal materials had the highest risk of metal content. (4) Combined with the pharmacopoeia metal limit standards implemented in 2019, the exceeding rate of Pb in TCMM was the highest, with a maximum value of 37.67%; among the six major types of TCMM, the medicinal materials with the highest exceeding rate were herba-type medicinal materials, among which Hg had the highest exceeding rate of 23.08%; in terms of medicinal parts, the highest exceeding rate of metals was in leaf-type medicinal materials, among which Pb had the highest exceeding rate of 37.67%. On the whole, the situation in regard to metal residues in TCMM was acceptable, but it cannot be ignored. It needed to be paid attention to in the industrialization and management of TCMM.
Topics: Arsenic; Asian People; Cadmium; China; Chromium; Drugs, Chinese Herbal; Environmental Monitoring; Environmental Pollutants; Fruit; Humans; Metals, Heavy; Plant Leaves; Tibet
PubMed: 32947212
DOI: 10.1016/j.ecoenv.2020.111311