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Ecotoxicology and Environmental Safety Jul 2022The investigation of chemical speciation of primary toxic metal(loid)s (Cd, Pb, and As) in soil profile in nonferrous metal smelting site is a key to the assessment of...
The investigation of chemical speciation of primary toxic metal(loid)s (Cd, Pb, and As) in soil profile in nonferrous metal smelting site is a key to the assessment of their mobility characteristics and formulation of subsequent remediation strategy. In this study, 74 soil samples were collected at 12 different soil profiles; soil physio-chemical properties and total content of Cd, Pb and As and corresponding chemical speciation were also determined. The results showed that the mean total concentration followed the order of Pb > As > Cd. A large proportion of Pb, Cd and As were accumulated in upper soil profiles (depth < 3 m). Heavy pollution of Pb, Cd and As were observed in the whole soil profile at the area of fuel oil storage tank (ZY6) and lead smelting area (ZY8). The dominant fraction of Cd was exchangeable fraction (F1); Pb was dominant in Fe/Mn oxides-bound fraction (F3) in most cases; Crystallized Fe/Al hydrous oxides bound fraction (F4) generally accounted for a large proportion of As. Mobility factor (MF) followed the order Cd > As > Pb, indicating that Cd was the most mobile element in soil profiles. Pearson correlation analysis found that MF was significantly positively correlated to soil silt; the F4 fraction percentage of As was significantly positively correlated to soil redox potential (Eh). Additionally, MF was found to be positively correlated to crystalline iron (Fe), while negatively correlated to amorphous iron (Fe). The findings reported in this study, on the basis of distribution characteristics of chemical speciation could provide a new solution for future soil remediation at the site. Long-term solutions to metal(loid)s pollution might be offered by microbial-assisted soil washing technique that promotes the transformation of Fe/Mn oxides-bound fraction and organic/sulfide-bound fraction.
Topics: Arsenic; Cadmium; China; Environmental Monitoring; Iron; Lead; Metals, Heavy; Oxides; Soil; Soil Pollutants
PubMed: 35580509
DOI: 10.1016/j.ecoenv.2022.113617 -
Heart Rhythm Jul 2022Data on lead management in patients with congenital complete heart block (CCHB) with cardiac implantable electronic devices are lacking.
BACKGROUND
Data on lead management in patients with congenital complete heart block (CCHB) with cardiac implantable electronic devices are lacking.
OBJECTIVE
The purpose of this study was to describe the natural history and outcomes in patients with CCHB with cardiac implantable electronic devices undergoing transvenous lead extraction (TLE).
METHODS
Data on all attempted TLE procedures in patients with CCHB at 2 institutions between 2011 and 2021 were collected from a retrospective registry.
RESULTS
Overall, 16 patients (mean age at transvenous device implant 13.8 ± 4.7 years) were included. Before TLE, patients underwent an average of 2.25 ± 1.3 generator changes, 3 (19%) underwent cardiac resynchronization therapy upgrade, and 7 (44%) underwent a lead revision with subsequently abandoned leads. Mean patient age at TLE was 34.4 ± 9.4 years with a mean duration of lead implant of 19.2 ± 6.9 years. Lead malfunction (n = 11 [69%]) and infection (n = 5 [31%]) were the most common indications for TLE. A total of 38 leads were removed, with complete procedural success achieved in 14 of 16 (87.5%). Two (12.5%) major complications occurred, including right ventricular laceration and superior vena cava tear requiring sternotomies. All patients survived at 1-year follow-up.
CONCLUSION
Patients with CCHB represent a unique cohort highlighted by several generator changes, lead revisions, and abandoned leads at a young age, along with a long duration of lead dwelling time and a high prevalence of lead malfunction requiring TLE. There may be a high risk of major complications during TLE, suggesting TLE should be performed only in experienced centers. Larger studies are needed to confirm these findings.
Topics: Defibrillators, Implantable; Device Removal; Heart Block; Humans; Lasers; Pacemaker, Artificial; Retrospective Studies; Treatment Outcome; Vena Cava, Superior
PubMed: 35257976
DOI: 10.1016/j.hrthm.2022.02.031 -
Frontiers in Neurorobotics 2022State-of-the-art knee braces use a polycentric mechanism with a predefined locus of the instantaneous center of rotation (centrode) and most exoskeleton devices use a...
State-of-the-art knee braces use a polycentric mechanism with a predefined locus of the instantaneous center of rotation (centrode) and most exoskeleton devices use a knee mechanism with a single axis of rotation. However, human knees do not share a common centrode nor do they have a single axis. This leads to misalignment between the assistive device's joint axis and the user's knee axis, resulting in device migration and interaction forces, which can lead to sores, pain, and abandonment of the device over time. There has been some research into self-aligning knee mechanisms; however, there is a lack of consensus on the benefit of these mechanisms. There is no research that looked purely at the impact of the knee mechanisms, either. In this article, we compare three different knee brace mechanisms: single axis (SA), polycentric with predefined centrode (PPC), and polycentric with a self-aligning center of rotation (PSC). We designed and conducted an experiment to evaluate different joint mechanisms on device migration and interaction forces. Brace material, weight, size, cuff design, fitment location, and tightness were consistent across trials, making the knee joint mechanism the sole variable. The brace mechanisms had no significant effect on walking kinematics or kinetics. However, the PPC brace had greater interaction forces on the top brace strap than the SA and PSC. The PSC and SA had significantly lower interaction forces on the bottom strap compared to the PPC brace. The PSC had significantly less migration than both the SA and PPC braces. These results show that a PPC mechanism may not be beneficial for a wide range of users. This also shows that the PSC mechanisms may improve mechanism alignment and lessen device migration.
PubMed: 35706552
DOI: 10.3389/fnbot.2022.790070 -
Current Opinion in Gastroenterology Sep 2004Clinicians are learning more about chronic pancreatitis but are entering an era of some confusion, primarily driven by uncovering new etiologies of chronic pancreatitis....
PURPOSE OF REVIEW
Clinicians are learning more about chronic pancreatitis but are entering an era of some confusion, primarily driven by uncovering new etiologies of chronic pancreatitis. Ideally, this knowledge will lead to better diagnosis and treatment, and abandonment of ill-conceived treatments. In contrast with previous reviews, this review highlights select contributions this year that may develop into true advances in chronic pancreatitis.
RECENT FINDINGS
Small steps have been made to understand better the molecular basis of chronic pancreatitis. Diagnosis of early chronic pancreatitis remains challenging. Rapid diagnosis by combining endoscopy and a direct stimulatory test of pancreatic function may lead to more widespread use of function testing, but this test is not ready for clinical use. Application of microarray and proteomic technologies may aid future diagnosis of chronic pancreatitis. The failure to account clearly for the phenotype of patients with chronic pancreatitis may confound delineating the etiologies of chronic pancreatitis. Clinical description and studies of autoimmune pancreatitis have led to the realization that steroids are an effective treatment for this form of chronic pancreatitis. Genetic-based studies have provided insight into the pathogenic mechanisms of chronic pancreatitis. Investigation of the role of stellate cells, an essential component fibrogenesis, has led to identification of potential novel treatments for chronic pancreatitis.
SUMMARY
Ongoing basic and clinical research this past year has characterized further the histologic, genetic, molecular, and clinical aspects of chronic pancreatitis, efforts that may translate into novel therapies once well-designed, controlled studies have been performed.
PubMed: 15689677
DOI: 10.1097/00001574-200409000-00005 -
BioMed Research International 2017Acidic mine drainage (AMD) is regarded as a pollutant and considered as potential source of valuable metals. With diminishing metal resources and ever-increasing demand... (Review)
Review
Acidic mine drainage (AMD) is regarded as a pollutant and considered as potential source of valuable metals. With diminishing metal resources and ever-increasing demand on industry, recovering AMD metals is a sustainable initiative, despite facing major challenges. AMD refers to effluents draining from abandoned mines and mine wastes usually highly acidic that contain a variety of dissolved metals (Fe, Mn, Cu, Ni, and Zn) in much greater concentration than what is found in natural water bodies. There are numerous remediation treatments including chemical (lime treatment) or biological methods (aerobic wetlands and compost bioreactors) used for metal precipitation and removal from AMD. However, controlled biomineralization and selective recovering of metals using sulfidogenic bacteria are advantageous, reducing costs and environmental risks of sludge disposal. The increased understanding of the microbiology of acid-tolerant sulfidogenic bacteria will lead to the development of novel approaches to AMD treatment. We present and discuss several important recent approaches using low sulfidogenic bioreactors to both remediate and selectively recover metal sulfides from AMD. This work also highlights the efficiency and drawbacks of these types of treatments for metal recovery and points to future research for enhancing the use of novel acidophilic and acid-tolerant sulfidogenic microorganisms in AMD treatment.
Topics: Bacteria; Biodegradation, Environmental; Hydrogen-Ion Concentration; Metals, Heavy; Mining; Water; Water Microbiology
PubMed: 29119111
DOI: 10.1155/2017/7256582 -
JACC. Clinical Electrophysiology Jan 2017
Topics: Defibrillators, Implantable; Pacemaker, Artificial
PubMed: 29759688
DOI: 10.1016/j.jacep.2016.09.005 -
International Journal of Environmental... Mar 2016Understanding spatial variation of potentially toxic trace elements (PTEs) in soil is necessary to identify the proper measures for preventing soil contamination at both... (Comparative Study)
Comparative Study
Understanding spatial variation of potentially toxic trace elements (PTEs) in soil is necessary to identify the proper measures for preventing soil contamination at both operating and abandoned mining areas. Many studies have been conducted worldwide to explore the spatial variation of PTEs and to create soil contamination maps using geostatistical methods. However, they generally depend only on inductively coupled plasma atomic emission spectrometry (ICP-AES) analysis data, therefore such studies are limited by insufficient input data owing to the disadvantages of ICP-AES analysis such as its costly operation and lengthy period required for analysis. To overcome this limitation, this study used both ICP-AES and portable X-ray fluorescence (PXRF) analysis data, with relatively low accuracy, for mapping copper and lead concentrations at a section of the Busan abandoned mine in Korea and compared the prediction performances of four different approaches: the application of ordinary kriging to ICP-AES analysis data, PXRF analysis data, both ICP-AES and transformed PXRF analysis data by considering the correlation between the ICP-AES and PXRF analysis data, and co-kriging to both the ICP-AES (primary variable) and PXRF analysis data (secondary variable). Their results were compared using an independent validation data set. The results obtained in this case study showed that the application of ordinary kriging to both ICP-AES and transformed PXRF analysis data is the most accurate approach when considers the spatial distribution of copper and lead contaminants in the soil and the estimation errors at 11 sampling points for validation. Therefore, when generating soil contamination maps for an abandoned mine, it is beneficial to use the proposed approach that incorporates the advantageous aspects of both ICP-AES and PXRF analysis data.
Topics: Copper; Environmental Monitoring; Environmental Pollution; Lead; Mining; Republic of Korea; Soil; Soil Pollutants; Spatial Analysis; Spectrometry, X-Ray Emission; Spectrophotometry, Atomic; Trace Elements
PubMed: 27043594
DOI: 10.3390/ijerph13040384 -
American Journal of Public Health Dec 1998In 1991, the Public Health Service published the Strategic Plan for the Elimination of Childhood Lead Poisoning. This document marked a fundamental shift in federal... (Review)
Review
In 1991, the Public Health Service published the Strategic Plan for the Elimination of Childhood Lead Poisoning. This document marked a fundamental shift in federal policy from finding and treating lead-poisoned children to authentic primary prevention. It spelled out a 15-year strategy to achieve this goal and provided a cost-benefit analysis showing that the monetized benefits far exceeded the costs of abatement. A strong national effort to eliminate the disease developed. Now, 7 years after publication of the plan, primary prevention of lead exposure has been abandoned. This article examines the role of some prevailing attitudes and institutions in derailing the effort. Some institutions--the lead industry, real estate interests, and insurance interests--behaved as anticipated. Others, including private pediatricians, the American Academy of Pediatrics, some federal agencies, and a public interest group ostensibly dedicated to eliminating lead poisoning, also played an unexpected part in derailing the plan.
Topics: Attitude of Health Personnel; Child; Health Knowledge, Attitudes, Practice; Health Planning; Humans; Lead Poisoning; Population Surveillance; Primary Prevention; Public Health Practice; United States; United States Public Health Service
PubMed: 9842392
DOI: 10.2105/ajph.88.12.1871 -
MRI in pediatric and congenital heart disease patients with CIEDs and epicardial or abandoned leads.Pacing and Clinical Electrophysiology :... Aug 2020Heart Rhythm Society guidelines outlining magnetic resonance imaging (MRI) in patients with cardiac implantable electronic devices (CIEDs) excluded children and...
BACKGROUND
Heart Rhythm Society guidelines outlining magnetic resonance imaging (MRI) in patients with cardiac implantable electronic devices (CIEDs) excluded children and epicardial or abandoned leads due to theoretical risks of harm. Research investigating these risks is lacking. The primary objective of our study is to determine the incidence of adverse events to patients or CIEDs from MRI imaging. The secondary objective is to describe CIED-related artifact on MRI images.
METHODS
A single-center retrospective review was performed on all patients with CIEDs who underwent 1.5 Tesla MRI between July 2007 and May 2019. We subdivided patients among four cohorts: (1) patients <18 years of age, (2) epicardial leads, (3) abandoned endocardial leads, and (4) abandoned epicardial leads. Descriptive statistics pre- and post-MRI and at follow-up within 1.5 years were conducted.
RESULTS
Fifty-four MRIs were performed on 40 patients. Median age was 21.2 years (IQR 12.0-25.0). Eighteen (33%) MRIs contained abandoned leads; 20 (37%) contained epicardial leads. Three patients, one with abandoned epicardial leads and two with abandoned endocardial leads, experienced mild discomfort at the CIED site. One adult with endocardial leads experienced a pause in the heart rate while programmed in a nonpacing mode. No clinically important changes to CIED parameters occurred. Nine MRIs (17%), especially those with functional cardiac imaging, were uninterpretable due to image artifact.
CONCLUSION
In this study, pediatric and adult CHD patients with CIEDs, many with epicardial or abandoned leads, underwent MRIs without clinically significant complications. In some, CIED artifact reduced cardiac MRI image quality due to CIED position.
Topics: Adolescent; Adult; Artifacts; Child; Defibrillators, Implantable; Electrodes, Implanted; Female; Heart Defects, Congenital; Humans; Magnetic Resonance Imaging; Male; Patient Safety; Retrospective Studies
PubMed: 32533566
DOI: 10.1111/pace.13984 -
International Journal of Molecular... Feb 2022Specialist bacteria can synthesize nanoparticles from various metal ions in solution. Metal recovery with high efficiency can be achieved by metal-tolerant...
Specialist bacteria can synthesize nanoparticles from various metal ions in solution. Metal recovery with high efficiency can be achieved by metal-tolerant microorganisms that proliferate in a concentrated metal solution. In this study, we isolated bacteria ( sp. strain KKY-29) from a bacterial library collected from water near an abandoned mine in Komatsu City, Ishikawa Prefecture, Japan. KKY-29 was maintained in nutrient medium with lead acetate and synthesized hydrocerussite and pyromorphite nanoparticles inside the cell; KKY-29 also survived nanoparticle synthesis. Quantitative PCR analysis of genes related to phosphate metabolism showed that KKY-29 decomposed organic phosphorus to synthesize lead phosphate. KKY-29 also deposited various metal ions and synthesized metal nanoparticles when incubated in various metal salt solutions other than lead. The present study considers the development of biotechnology to recover lead as an economically valuable material.
Topics: Bacteria; Biodegradation, Environmental; Fresh Water; Lead; Phosphorus
PubMed: 35269625
DOI: 10.3390/ijms23052483