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1.
Environ Geochem Health ; 46(6): 187, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696018

RESUMO

The presence of toxic trace elements (TEs) has resulted in a worldwide deterioration in freshwater ecosystem quality. This study aimed to analyze the distribution of TEs, including chromium (Cr), nickel (Ni), arsenic (As), mercury (Hg), cadmium (Cd), and lead (Pb), in water, sediment, and organs of Tilapia (Oreochromis mossambicus) collected from selected inland water bodies in Tamil Nadu, India. The water samples exhibited a range of concentrations for TEs: Cr varied from 0.014 to 5.193 µg/L, Ni ranged from 0.283 to 11.133 µg/L, As ranged from 0.503 to 1.519 µg/L, Cd from 0.001 to 0.616 µg/L, and Pb ranged from non-detectable (ND) to 6.103 µg/L. The concentrations of TEs in sediment were found to vary within the following ranges: 5.259 to 32.621 mg/kg for Cr, 1.932 to 30.487 mg/kg for Ni, 0.129 to 0.563 mg/kg for As, 0.003 to 0.011 mg/kg for Cd, ND to 0.003 mg/kg for Hg, and 0.404 to 1.575 mg/kg for Pb. The study found that the accumulation pattern of TE in fishes across all selected areas was liver > bone > gill > muscle. The organs had TE concentrations of Cr (ND-0.769 mg/kg), Ni (ND-1.053 mg/kg), As (0.002-0.080 mg/kg), Pb (ND-0.411 mg/kg), and Hg (ND-0.067 mg/kg), which was below the maximum residual limit prescribed by EC and FSSAI. The bioconcentration factor (BCF) of TEs exhibited a greater magnitude in comparison with the biota-sediment accumulation factor due to the higher concentration of TEs in fish and lower level in water. The assessment of both carcinogenic and non-carcinogenic risks suggests that the consumption of Tilapia from the study region does not pose any significant risks.


Assuntos
Bioacumulação , Sedimentos Geológicos , Tilápia , Oligoelementos , Poluentes Químicos da Água , Animais , Tilápia/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Medição de Risco , Sedimentos Geológicos/química , Oligoelementos/análise , Oligoelementos/metabolismo , Índia , Monitoramento Ambiental , Metais Pesados/análise , Humanos , Água Doce
2.
J Contam Hydrol ; 263: 104339, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38564944

RESUMO

Plastic particles, measuring <5 mm in size, mainly originate from larger plastic debris undergoing degradation, fragmenting into even smaller fragments. The goal was to analyze the spatial diversity and polymer composition of microplastics (MPs) in North Chennai, South India, aiming to evaluate their prevalence and features like composition, dimensions, color, and shape. In 60 sediment samples, a combined count of 1589 particles were detected, averaging 26 particles per 5 g-1 of dry sediment. The water samples from the North Chennai vicinity encompassed a sum of 1588 particles across 71 samples, with an average of 22 items/L. The majority of MPs ranged in size from 1 mm to 500 µm. The ATR-FTIR results identified the predominant types of MPs as polystyrene, polyvinyl chloride, polyethylene, polyethylene terephthalate, and polypropylene in sediment and water. The spatial variation analysis revealed high MPs concentration in landfill sites, areas with dense populations, and popular tourist destinations. The pollution load index in water demonstrated that MPs had contaminated all stations. Upon evaluating the polymeric and pollution risks, it was evident that they ranged from 5.13 to 430.15 and 2.83 to 15,963.2, which is relatively low to exceedingly high levels. As the quantity of MPs and hazardous polymers increased, the level of pollution and corresponding risks also escalated significantly. The existence of MPs in lake water, as opposed to open well water, could potentially pose a cancer risk for both children and adults who consume it. Detecting MPs in water samples highlights the significance of implementing precautionary actions to alleviate the potential health hazards they create.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Microplásticos , Poluentes Químicos da Água , Microplásticos/análise , Índia , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Humanos , Medição de Risco , Plásticos/análise
3.
Int J Equity Health ; 23(1): 38, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409005

RESUMO

BACKGROUND: A high burden of physical, mental, and occupational health problems among migrant workers has been well-documented, but data on undocumented migrant workers are limited and their well-being has rarely been compared to that of the general population. METHODS: Using data from a cross-sectional survey of non-professional migrant workers in South Korea in early 2021, we described their physical, psychological, social well-being and health behaviors across a wide range of outcomes, including self-rated health, occupational injury, cigarette smoking, heavy alcohol consumption, meal pattern, happiness, mental illness, social support, and social participation. The outcomes were first compared between documented and undocumented migrant workers in generalized linear regressions adjusting for potential confounders. Then, the well-being of the migrant workers was compared against that of the general population using data from the Korean Happiness Survey, which is a nationally representative survey of the South Korean general population conducted in late 2020. The parametric g-formula was performed to adjust for potential confounders. RESULTS: After adjusting for potential confounders, the undocumented migrant workers were less likely to be happy or participate in social communities, and much more likely to have anxiety or depression, smoke cigarettes, or engage in heavy alcohol consumption than the documented migrant workers. When compared to the general South Korean population, an evident social gradient emerged for happiness and mental illness; the undocumented experienced the worst outcome, followed by the documented, and then the general population. Also, the undocumented migrant workers were more likely to smoke cigarettes than the general population. CONCLUSION: The undocumented migrant workers face considerably greater challenges in terms of mental health and happiness, demonstrate higher rates of risky health behaviors such as smoking and heavy drinking, and experience a lack of social support and community integration. A stark social gradient in happiness, mental illness, and cigarette smoking exists among the documented, undocumented migrant workers and the general population in South Korea. Socio-structural factors are likely to play a crucial role in contributing to the suboptimal level of overall well-being of undocumented migrant workers. Policy-level interventions as well as interpersonal efforts are in urgent need.


Assuntos
Migrantes , Humanos , Estudos Transversais , Saúde Mental , Transtornos de Ansiedade , Comportamentos Relacionados com a Saúde
4.
Environ Geochem Health ; 46(2): 35, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227063

RESUMO

This study assesses the bioaccumulation, ecological, and health risks associated with potentially toxic metals (PTMs), including Pb, Hg, Cd, As, and Cr in Hare Island, Thoothukudi. The results revealed that the concentration of PTMs in sediment, seawater, and S. wightii ranged from 0.095 to 2.81 mg kg-1, 0.017 to 1.515 mg L-1, and 0.076 to 5.713 mg kg-1, respectively. The highest concentrations of PTMs were found in the S. wightii compared to seawater and sediment. The high bioaccumulation of Hg and As in S. wightii suggests that it can be used as a bioindicator for these elements in this region. The ecological risk indices, which include individual, complex, biological, and ecological pollution indices, suggest that Hare Island had moderate contamination with Hg and Cd. However, there are no human health risks associated with PTMs. This study examines the current ecological and health risks associated with PTMs and emphasizes the importance of regular monitoring.


Assuntos
Lebres , Mercúrio , Alga Marinha , Humanos , Animais , Bioacumulação , Cádmio , Água do Mar
5.
Front Pediatr ; 11: 933623, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456570

RESUMO

Background: The rate of the prenatal diagnosis of congenital heart disease is increasing along with advances in fetal echocardiography techniques. Here, we aimed to investigate the trend of the use of fetal echocardiography over time and to compare the medical costs of congenital heart disease treatment according to whether fetal echocardiography was performed. Methods: We reviewed our hospital's database, and patients who underwent the first surgery for congenital heart disease within 30 days of birth during 2005-2007, 2011-2013, and 2017-2019 were included. The severity of congenital heart disease diagnosed in each case was evaluated according to The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Congenital Heart Surgery Mortality Scores (STS-EACTS Mortality Scores) and Mortality Categories (STAT Mortality Categories). Results: In total, 375 patients were analyzed, and fetal echocardiography use increased significantly after the 2010s compared with in 2005-2007 (19.1% vs. 39%, p = 0.032 in Mortality Category 1-3; 15.5% vs. 69.5%, p = 0.000 in Mortality Category 4-5). Additionally, the mean STS-EACTS Mortality Score was higher in prenatally diagnosed patients than in postnatally diagnosed patients (2.287 vs. 1.787, p = 0.001). In the recent period, there was no significant difference in hospitalization durations and medical costs according to whether or not fetal echocardiography was performed. Conclusions: This single center study showed the use of fetal echocardiography is increasing. Further, prenatal diagnosis with fetal echocardiography causing no differences in medical costs in recent years. Therefore, we suggest that fetal echocardiography can be applied more widely without increasing the economic burden.

6.
J Environ Manage ; 332: 117382, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36753844

RESUMO

Currently, international development requires innovative solutions to address imminent challenges like climate change, unsustainable food system, food waste, energy crisis, and environmental degradation. All the same, addressing these concerns with conventional technologies is time-consuming, causes harmful environmental impacts, and is not cost-effective. Thus, biotechnological tools become imperative for enhancing food and energy resilience through eco-friendly bio-based products by valorisation of plant and food waste to meet the goals of circular bioeconomy in conjunction with Sustainable Developmental Goals (SDGs). Genome editing can be accomplished using a revolutionary DNA modification tool, CRISPR-Cas9, through its uncomplicated guided mechanism, with great efficiency in various organisms targeting different traits. This review's main objective is to examine how the CRISPR-Cas system, which has positive features, could improve the bioeconomy by reducing food loss and waste with all-inclusive food supply chain both at on-farm and off-farm level; utilising food loss and waste by genome edited microorganisms through food valorisation; efficient microbial conversion of low-cost substrates as biofuel; valorisation of agro-industrial wastes; mitigating greenhouse gas emissions through forestry plantation crops; and protecting the ecosystem and environment. Finally, the ethical implications and regulatory issues that are related to CRISPR-Cas edited products in the international markets have also been taken into consideration.


Assuntos
Eliminação de Resíduos , Sistemas CRISPR-Cas , Ecossistema , Produtos Agrícolas
7.
Chemosphere ; 313: 137475, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36528154

RESUMO

Anthropogenic toxins are discharged into the environment and distributed through a variety of environmental matrices. Trace contaminant detection and analysis has advanced dramatically in recent decades, necessitating further specialized technique development. These pollutants can be mobile and persistent in small amounts in the environment, and ecological receptors will interact with it. Despite the fact that few researches have been undertaken on invertebrate exposure, accumulation, and biological implications, it is apparent that a wide range of pollutants can accumulate in the tissues of aquatic insects, earthworms, amphipod crustaceans, and mollusks. Due to long-term stability during long-distance transit, a number of chemical and microbiological agents that were not previously deemed pollutants have been found in various environmental compartments. The uptake of such pollutants by the aquatic organism is done through the process of bioaccumulation when dangerous compounds accumulate in living beings while biomagnification is the process of a pollutant becoming more hazardous as it moves up the trophic chain. Organic and metal pollution harms animals of every species studied so far, from bacteria to phyla in between. The environmental protection agency says these poisons harm humans as well as a variety of aquatic organisms when the water quality is sacrificed in typical wastewater treatment systems. Contrary to popular belief, treated effluents discharged into aquatic bodies contain considerable levels of Anthropogenic contaminants. This evolution necessitates a more robust and recent advancement in the field of remediation and their techniques to completely discharge the various organic and inorganic contaminants.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Animais , Humanos , Ecossistema , Poluentes Ambientais/análise , Poluentes Químicos da Água/análise , Organismos Aquáticos , Qualidade da Água , Monitoramento Ambiental/métodos
8.
Environ Res ; 214(Pt 1): 113824, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35830909

RESUMO

In recent years, wide spread of antibiotic-resistant microorganisms and genes emerging globally, an eco-friendly method for efficient degradation of antibiotics from the polluted environment is essential. Intimately coupled photocatalysis and biodegradation (ICPB) using gC3N4 for enhanced degradation of sulfamethoxazole (SMX) was investigated. The gC3N4 were prepared and coated on the carbon felt. The mixed culture biofilm was developed on the surface as a biocarrier. The photocatalytic degradation showed 74%, and ICPB exhibited 95% SMX degradation efficiency. ICPB showed superior visible light adsorption, photocatalytic activity, and reduced charge recombination. The electron paramagnetic resonance spectrum confirms that the generation of •OH and O2• radicals actively participated in the degradation of SMX into biodegradable intermediated compounds, and then, the bacterial communities present in the biofilm mineralized the biodegradable compound into carbon dioxide and water. Moreover, the addition of NO3-, PO4-, and Cl- significantly enhanced the degradation efficiency by trapping the surface electron. Stability experiments confirmed that gC3N4 biohybrid can maintain 85% SMX degradation efficiency after 5 consecutive recycling. Extracellular polymeric substances characterization results show that biohybrid contains 47 mg/L, 14 mg/L, and 13 mg/L protein, carbohydrate, and humic acid, respectively, which can protect the bacterial communities from the antibiotic toxicity and reactive oxygen species. Furthermore, biotoxicity was investigated using degradation products on E.coli and results revealed 83% detoxification efficiency. Overall, this study suggested that gC3N4 photocatalyst in an ICPB can be used as a promising eco-friendly method to degrade sulfamethoxazole efficiently.


Assuntos
Sulfametoxazol , Titânio , Antibacterianos , Bactérias , Biodegradação Ambiental , Biofilmes
9.
Environ Res ; 213: 113612, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35716816

RESUMO

The present study is an attempt to assess the cytogenotoxic effect of untreated and methyl orange treated with Oedogonium subplagiostomum AP1 on Allium cepa roots. On the fifth day, root growth, root length, mitotic index, mitotic inhibition/depression, and chromosomal abnormalities were measured in root cells of Allium cepa subjected to untreated and treated methyl orange dye solutions. Roots exposed to treated dye solution exhibited maximum root growth, root length and mitotic index, whereas roots exposed to untreated dye solution had the most mitotic inhibition and chromosomal abnormalities. Allium cepa exposed to untreated dye solution revealed chromosomal aberrations such as disoriented and abnormal chromosome grouping, vagrant and laggard chromosomes, chromosomal loss, sticky chain and disturbed metaphase, pulverised and disturbed anaphase, chromosomal displacement in anaphase, abnormal telophase, and chromosomal bridge at telophase, spindle disturbances and binucleate cells. The comet test was used to quantify DNA damage in the root cells of A. cepa subjected to untreated and treated methyl orange solutions in terms of tail DNA (percent) and tail length. The results concluded that A. cepa exposed to methyl orange induced DNA damage whereas meager damage was noted in the treated dye solution. As a result, the research can be used as a biomarker to detect the genotoxic effects of textile dyes on biota.


Assuntos
Allium , Cebolas , Compostos Azo , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA , Índice Mitótico , Cebolas/genética , Raízes de Plantas
10.
Artigo em Inglês | MEDLINE | ID: mdl-35270495

RESUMO

The societal disruptions resulting from the coronavirus disease 2019 (COVID-19) pandemic may have caused changes in smoking and alcohol consumption. Using data from the Koreans' Happiness Survey, a nationally representative survey in South Korea, we (1) described population-level smoking and drinking behaviors; (2) assessed changes in smoking and drinking behaviors during the COVID-19 pandemic; and (3) identified employment, economic, and sociodemographic factors associated with these changes using multinomial logistic regression. The overall amount of smoking and drinking decreased during the pandemic, but the changes were heterogeneous across subgroups. Male gender, receipt of the basic living allowance, self-employment, unemployment, and chronic disease status were associated with increased smoking, while higher household income, temporary worker status, living with someone (versus alone), and having fewer offline friends were associated with decreased smoking. Male gender, self-employment, living alone, having more offline friends, and chronic disease status were associated with increased drinking, while younger age, male gender, low and high household income (i.e., a U-shaped relationship), long-term rent with a deposit, temporary worker status, and chronic disease status were associated with decreased drinking. Our findings provide evidence on changes in smoking and drinking during the COVID-19 pandemic in South Korea and differential changes across subgroups.


Assuntos
COVID-19 , Consumo de Bebidas Alcoólicas/epidemiologia , COVID-19/epidemiologia , Emprego , Humanos , Masculino , Pandemias , República da Coreia/epidemiologia , SARS-CoV-2 , Fumar/epidemiologia , Fatores Sociodemográficos
11.
Chemosphere ; 296: 133976, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35176298

RESUMO

Microplastics in personal care and food products are given much importance globally due to the adverse impact of microplastics on living beings. In the present study, microplastics from ten different commercially sold toothpaste in India were extracted by vacuum filtration and characterized with microscopic and Fourier-transform infrared spectroscopic analyses. Results revealed that colorless fragments and fibers were the microparticle types of common occurrence which ranged from 0.2 to 0.9% weight in the toothpaste with an abundance range of 32.7-83.2%. Fifty percent of the toothpaste samples showed more than 50% microplastic particle abundance indicating that the microplastic plastic particles were added by the manufacturers. The minimum size of microplastics recorded in the present study was 3.5 µm with a maximum size exceeding 400 µm. The maximum number of microplastics in the toothpaste was 167, 508 and 193 respectively, distributed in the size range of <100 µm, 100-400 µm, and >400 µm. The present study recorded four major polymer types, viz., cellophane, polypropylene, polyvinyl chloride, and polyamide in the toothpaste samples. Surprisingly, polyethylene-a common polymer reported in toothpaste was not traced in the present samples. Regarding the Indian context, the current study is a new addition to the knowledge of the occurrence of microplastics in toothpaste. The average annual addition of microplastics into the environment through toothpaste was calculated as 1.4 billion g/year for India, posing a significant threat to the environment.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Plásticos/química , Polímeros , Medição de Risco , Cremes Dentais , Poluentes Químicos da Água/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-34444597

RESUMO

INTRODUCTION: To make more efficient use of limited resources, Vietnam incorporated health technology assessment (HTA) into the decision-making process for the health insurance benefit package in 2014. We evaluated progress in HTA institutionalization in Vietnam based on the theoretical framework developed by the National Institute for Health and Care Excellence and the Health Intervention and Technology Assessment Program, identified negative and conducive factors for HTA development, and finally suggested policy recommendations that fit the Vietnamese context. METHODS: Semi-structured in-depth qualitative interviews were conducted between December 2017 and March and April 2018 with a purposive sample of 24 stakeholders involved in decision-making for health insurance reimbursement. We employed thematic analysis to examine themes within the data. RESULTS: Despite a variety of activities (e.g., training and advising/mentoring) and a substantial level of output (e.g., policy statements, focal points assigned, and case studies/demonstration projects), Vietnam has not yet reached the policy decision stage based on HTA with scientific integrity and active stakeholder participation. Most respondents, except some clinicians, supported the use of HTA. The lack of capacity of human resources in the government sector and academia, the limited data infrastructure, the absence of guidelines, the government's interest in immediate budget-saving, and public resistance were identified as barriers to the advancement of HTA. CONCLUSIONS: A structured data repository, guidelines based on the Vietnamese context for both policy decision-making at the central level and daily clinical decision-making at the micro-level, and integration of a participatory process into HTA are suggested as priorities for HTA institutionalization in Vietnam.


Assuntos
Política de Saúde , Avaliação da Tecnologia Biomédica , Humanos , Formulação de Políticas , Pesquisa Qualitativa , Vietnã
14.
BMC Cardiovasc Disord ; 20(1): 227, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32414329

RESUMO

BACKGROUND: As a result of advances in pediatric care and diagnostic testing, there is a growing population of adults with congenital heart disease (ACHD). The purpose of this study was to better define the epidemiology and changes in the trend of hospitalizations for ACHD in Korean society. METHODS: We reviewed outpatient and inpatient data from 2005 to 2017 to identify patient ≥18 years of age admitted for acute care with a congenital heart disease (CHD) diagnosis in the pediatric cardiology division. We tried to analyze changes of hospitalization trend for ACHD. RESULTS: The ratio of outpatients with ACHD increased 286.5%, from 11.1% (1748/15,682) in 2005 to 31.8% (7795/24,532) in 2017. The number of ACHD hospitalizations increased 360.7%, from 8.9% (37/414) in 2005 to 32.1% (226/705) in 2017. The average patient age increased from 24.3 years in 2005 to 27.4 in 2017. The main diagnosis for admission of ACHD is heart failure, arrhythmia and Fontan-related complications. The annual ICU admission percentage was around 5% and mean length of intensive care unit (ICU) stay was 8.4 ± 14.6 days. Mean personal hospital charges by admission of ACHD increased to around two times from 2005 to 2017. (from $2578.1 to $3697.0). Total annual hospital charges by ACHD markedly increased ten times (from $95,389.7 to $831,834.2). CONCLUSIONS: The number of hospital cares for ACHD dramatically increased more than five times from 2005 to 2017. We need preparations for efficient healthcare for adults with CHD such as a multi-dimensional approach, effective communication, and professional training.


Assuntos
Serviço Hospitalar de Cardiologia/tendências , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/terapia , Hospitalização/tendências , Pediatria/tendências , Sobreviventes , Adolescente , Adulto , Serviço Hospitalar de Cardiologia/economia , Feminino , Gastos em Saúde/tendências , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/economia , Preços Hospitalares/tendências , Custos Hospitalares/tendências , Hospitalização/economia , Humanos , Masculino , Pediatria/economia , Estudos Retrospectivos , Seul/epidemiologia , Fatores de Tempo , Adulto Jovem
15.
J Biomech ; 79: 191-197, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30173933

RESUMO

The purpose of this study was to examine the potential of digital tomosynthesis (DTS) derived cancellous bone textural measures to predict vertebral strength under conditions simulating a wedge fracture. 40 vertebral bodies (T6, T8, T11, and L3 levels) from 5 male and 5 female cadaveric donors were utilized. The specimens were scanned using dual energy X-ray absorptiometry (DXA) and high resolution computed tomography (HRCT) to obtain measures of bone mineral density (BMD) and content (BMC), and DTS to obtain measures of bone texture. Using a custom loading apparatus designed to deliver a nonuniform displacement resulting in a wedge deformity similar to those observed clinically, the specimens were loaded to fracture and their fracture strength was recorded. Mixed model regressions were used to determine the associations between wedge strength and DTS derived textural variables, alone and in the presence of BMD or BMC information. DTS derived fractal, lacunarity and mean intercept length variables correlated with wedge strength, and individually explained up to 53% variability. DTS derived textural variables, notably fractal dimension and lacunarity, contributed to multiple regression models of wedge strength independently from BMC and BMD. The model from a scan orientation transverse to the spine axis and in the anterior-posterior view resulted in highest explanatory capability (R2adj = 0.91), with a scan orientation parallel to the spine axis and in the lateral view offering an alternative (R2adj = 0.88). In conclusion, DTS can be used to examine cancellous texture relevant to vertebral wedge strength, and potentially complement BMD in assessment of vertebral fracture risk.


Assuntos
Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/fisiologia , Fenômenos Mecânicos , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiologia , Tomografia Computadorizada por Raios X , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
16.
J Prosthet Dent ; 116(4): 536-542, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27174406

RESUMO

STATEMENT OF PROBLEM: The fit of an interim implant restoration (IIR) is important for the effective treatment of patients with partial edentulism. However, no clinical trials have evaluated the marginal and internal fittings achieved with various fabrication methods. PURPOSE: The purpose of this in vitro study was to evaluate and compare the marginal and internal discrepancies in IIRs produced with 3 different methods. MATERIAL AND METHODS: Partially edentulous maxillary and mandibular casts from a transfer abutment were used. Prostheses were prepared by applying wax to the implant abutment. Shapes were copied using putty. IIRs were fabricated from poly(methyl methacrylate) for a conventional system with thermoplastic resin (CTR, n=40), a 4-axial milling machine with a crown-designed standard template library for a subtractive manufacturing system with Pekkton milling (SPM, n=40), and a 3-dimensional printer for an additive manufacturing system with digital light processing (ADL, n=40). The marginal and internal discrepancies were evaluated in each group using the silicone replica technique. The space between the abutment and the intaglio surface of the prosthesis was evaluated with a digital microscope (×160 magnification). Results were analyzed with nonparametric 2-way analysis of variance using rank-transformed values and Tukey post hoc test (α=.05). RESULTS: The fabricated IIRs were significantly different at all points (P<.001). Moreover, ADL was superior to CTR and SPM. IIRs were significantly different only at the intermarginal discrepancy (the vertical discrepancy between the crown and the point where the margin becomes round and changes to the axial wall), the axiogingival discrepancy (the vertical discrepancy between the internal surface and the axial wall adjacent to the gingival wall of the abutment), and the occlusal discrepancy (the vertical discrepancy between the occlusal wall of the abutment and the internal surface; this discrepancy comprises the internal discrepancy; P<.001). No significant differences were found among the IIRs at the marginal discrepancy (the vertical discrepancy between the abutment margin and the crown; P>.111) and the axio-occlusal discrepancy (the vertical discrepancy between the axial wall adjacent to the occlusal wall of the abutment and the internal surface; this discrepancy comprises the internal discrepancy; P>.257). CONCLUSIONS: ADL was superior to the other 2 fabrication methods. However, all 3 methods were suitable because they produced a marginal fit which was within the clinically acceptable range.


Assuntos
Adaptação Marginal Dentária , Planejamento de Prótese Dentária/métodos , Prótese Parcial Temporária , Dente Suporte , Técnica de Fundição Odontológica , Projeto do Implante Dentário-Pivô , Humanos , Técnicas In Vitro
17.
Ann Biomed Eng ; 44(3): 705-24, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26790865

RESUMO

The elastic properties of engineered biomaterials and tissues impact their post-implantation repair potential and structural integrity, and are critical to help regulate cell fate and gene expression. The measurement of properties (e.g., stiffness or shear modulus) can be attained using elastography, which exploits noninvasive imaging modalities to provide functional information of a material indicative of the regeneration state. In this review, we outline the current leading elastography methodologies available to characterize the properties of biomaterials and tissues suitable for repair and mechanobiology research. We describe methods utilizing magnetic resonance, ultrasound, and optical coherent elastography, highlighting their potential for longitudinal monitoring of implanted materials in vivo, in addition to spatiotemporal limits of each method for probing changes in cell-laden constructs. Micro-elastography methods now allow acquisitions at length scales approaching 5-100 µm in two and three dimensions. Many of the methods introduced in this review are therefore capable of longitudinal monitoring in biomaterials and tissues approaching the cellular scale. However, critical factors such as anisotropy, heterogeneity and viscoelasity-inherent in many soft tissues-are often not fully described and therefore require further advancements and future developments.


Assuntos
Materiais Biocompatíveis , Técnicas de Imagem por Elasticidade/métodos , Engenharia Tecidual , Animais , Humanos
18.
Med Eng Phys ; 37(1): 109-20, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25498138

RESUMO

Digital tomosynthesis (DTS) provides slice images of an object using conventional radiographic methods with high in-plane resolution. The objective of this study was to explore the potential of DTS for describing microstructural, stiffness and stress distribution properties of vertebral cancellous bone. Forty vertebrae (T6, T8, T11, and L3) from 10 cadavers (63-90 years) were scanned using microCT and DTS. Anisotropy (µCT.DA), and the specimen-average and standard deviation of trabecular bone volume fraction (BV/TV), thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp) were obtained using stereology. Apparent modulus (EFEM), and the magnitude (VMExp/σapp) and variability (VMCV) of trabecular stresses were calculated using microCT-based finite element modeling. Mean intercept length, line fraction deviation and fractal parameters were obtained from coronal DTS slices, then correlated with stereological and finite element parameters using linear regression models. Twenty-one DTS parameters (out of 27) correlated to BV/TV, Tb.Th, Tb.N, Tb.Sp and/or µCT.DA (p<0.0001-p<0.05). DTS parameters increased the explained variability in EFEM and VMCV (by 9-11% and 13-19%, respectively; p<0.0001-p<0.04) over that explained by BV/TV. In conclusion, DTS has potential for quantitative assessment of cancellous bone and may be used as a modality complementary to those measuring bone mass for assessing spinal fracture risk.


Assuntos
Coluna Vertebral/diagnóstico por imagem , Tomografia/métodos , Idoso , Idoso de 80 Anos ou mais , Anisotropia , Elasticidade , Feminino , Análise de Elementos Finitos , Fractais , Humanos , Modelos Lineares , Masculino , Tamanho do Órgão , Radiografia , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/fisiologia , Estresse Mecânico
19.
ACS Chem Biol ; 8(8): 1803-14, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23725454

RESUMO

Diabetes mellitus is a global epidemic with major impacts on human health and society. Drug discovery for diabetes can be facilitated by the development of a rapid, vertebrate-based screen for identifying new insulin mimetic compounds. Our study describes the first development of a zebrafish-based system based on direct monitoring of glucose flux and validated for identifying novel anti-diabetic drugs. Our system utilizes a fluorescent-tagged glucose probe in an experimentally convenient 96-well plate format. To validate our new system, we identified compounds that can induce glucose uptake via activity-guided fractionation of the inner shell from the Japanese Chestnut (Castanea crenata). The best performing compound, UP3.2, was identified as fraxidin and validated as a novel insulin mimetic using a mammalian adipocyte system. Additional screening using sets of saponin- and triazine-based compounds was undertaken to further validate this assay, which led to the discovery of triazine PP-II-A03 as a novel insulin mimetic. Moreover, we demonstrate that our zebrafish-based system allows concomitant toxicological analysis of anti-diabetic drug candidates. Thus, we have developed a rapid and inexpensive vertebrate model that can enhance diabetes drug discovery by preselecting hits from chemical library screens, before testing in relatively expensive rodent assays.


Assuntos
Biomimética , Cumarínicos/química , Descoberta de Drogas , Glucose/química , Insulina/química , Animais , Bioensaio/economia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glucose/metabolismo , Humanos , Hipoglicemiantes/química , Fatores de Tempo , Peixe-Zebra
20.
J Card Surg ; 28(2): 168-73, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23356430

RESUMO

BACKGROUND: The early effect of pulmonary regurgitation (PR) on both ventricular volume and function has not been well established in children. We evaluated the early effect of PR on both ventricular volume and function in young children. METHODS: Among patients who underwent total repair of pulmonary atresia with ventricular septal defect between January 2007 and December 2008, cardiac magnetic resonance imaging (CMRI) was performed in 12 patients at a median interval of 15.6 months (6-22 months). Valveless right ventricular outflow tract (RVOT) reconstruction was performed in five patients (valveless group) and RVOT reconstruction using valved conduit in seven patients (valve group). Age and weight at operation, and the interval between the operation and CMRI were not different between the groups. RESULTS: We observed a higher pulmonary regurgitant fraction (p = 0.003), a higher right ventricular end-diastolic volume index (RVEDVI) (p = 0.003), a higher right ventricular end-systolic volume index (p = 0.003), a higher left ventricular end-diastolic volume index (p = 0.010), a higher left ventricular end-systolic volume index (p = 0.018), and a lower left ventricular ejection fraction (LVEF; p = 0.048) in the valveless group. Right ventricular ejection fraction (RVEF) was not different between two groups. The RVEDVI was negatively correlated with RVEF (rho = -0.601, p = 0.039) and LVEF (rho = -0.580, p = 0.048). CONCLUSIONS: Both ventricular volumes increased and left ventricular function was compromised, but right ventricular function was preserved early after the exposure to PR in children. Right ventricular volume was associated with both ventricular functions.


Assuntos
Comunicação Interventricular/cirurgia , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/fisiopatologia , Atresia Pulmonar/cirurgia , Insuficiência da Valva Pulmonar/fisiopatologia , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Anormalidades Múltiplas/cirurgia , Pré-Escolar , Feminino , Seguimentos , Comunicação Interventricular/complicações , Implante de Prótese de Valva Cardíaca , Humanos , Lactente , Masculino , Complicações Pós-Operatórias/diagnóstico , Atresia Pulmonar/complicações , Insuficiência da Valva Pulmonar/diagnóstico , Insuficiência da Valva Pulmonar/etiologia , Resultado do Tratamento , Enxerto Vascular , Disfunção Ventricular Esquerda/diagnóstico
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