共查询到20条相似文献,搜索用时 31 毫秒
1.
Background
Noise exposure is a well-known contributor to work-related hearing loss. Recent biological evidence suggests that exposure to ototoxic chemicals such as organic solvents and heavy metals may be additional contributors to hearing loss. However, in industrial settings, it is difficult to determine the risks of hearing loss due to these chemicals in workplaces accompanied by excessive noise exposure. A few studies suggest that the effect of noise may be enhanced by ototoxic chemicals. Therefore, this study investigated whether co-exposure to organic solvents and/or heavy metals in the workplace modifies the risk of noise exposure on hearing loss in a background of excessive noise.Methods
We examined 30,072 workers nationwide in a wide range of industries from the Korea National Occupational Health Surveillance 2009. Data on industry-based exposure (e.g., occupational noise, heavy metals, and organic solvents) and subject-specific health outcomes (e.g., audiometric examination) were collected. Noise was measured as the daily 8-h time-weighted average level. Air conduction hearing thresholds were measured from 0.5 to 6 kHz, and pure-tone averages (PTA) (i.e., means of 2, 3, and 4 kHz) were computed.Results
In the multivariate linear model, PTA increment with occupational noise were 1.64-fold and 2.15-fold higher in individuals exposed to heavy metals and organic solvents than in unexposed individuals, respectively.Conclusion
This study provides nationwide evidence that co-exposure to heavy metals and/or organic solvents may exacerbate the effect of noise exposure on hearing loss in workplaces. These findings suggest that workers in industries dealing with heavy metals or organic solvents are susceptible to such risks. 相似文献2.
María Eugenia Caba?a-Mu?oz José María Parmigiani-Izquierdo Luis Alberto Bravo-González Hee-Moon Kyung José Joaquín Merino 《PloS one》2015,10(6)
Background
The induction of oxidative stress by Hg can affect antioxidant enzymes. However, epidemiological studies have failed to establish clear association between dental fillings presence and health problems.Objectives
To determine whether heavy metals (in hair), antioxidant enzymes (SOD-1) and glutathione levels could be affected by the chronic presence of heavy metals in women who had dental amalgam fillings.Materials and Methods
55 hair samples (42 females with amalgam fillings and 13 female control subjects) were obtained. All subjects (mean age 44 years) who had dental amalgam filling for more than 10 years (average 15 years). Certain metals were quantified by ICP-MS (Mass Spectrophotometry) in hair (μg/g: Al, Hg, Ba, Ag, Sb, As, Be, Bi, Cd, Pb, Pt, Tl, Th, U, Ni, Sn, Ti) and SOD-1 and Glutathione (reduced form) levels in plasma. Data were compared with controls without amalgams, and analyzed to identify any significant relation between metals and the total number of amalgam fillings, comparing those with four or less (n = 27) with those with more than four (n = 15). As no significant differences were detected, the two groups were pooled (Amlgam; n = 42).Findings
Hg, Ag, Al and Ba were higher in the amalgam group but without significant differences for most of the heavy metals analyzed. Increased SOD-1 activity and glutathione levels (reduced form) were observed in the amalgam group. Aluminum (Al) correlated with glutathione levels while Hg levels correlated with SOD-1. The observed Al/glutathione and Hg/SOD-1 correlation could be adaptive responses against the chronic presence of mercury.Conclusions
Hg, Ag, Al and Ba levels increased in women who had dental amalgam fillings for long periods. Al correlated with glutathione, and Hg with SOD-1. SOD-1 may be a possible biomarker for assessing chronic Hg toxicity. 相似文献3.
Objective
We investigated the relationship between saliva and dental biofilm characteristics, oral hygiene behaviours and the number of remaining teeth in a sample of older Koreans.Materials and methods
This cross‐sectional study included 133 participants, aged 65 years and older, recruited from senior welfare facilities in Incheon, South Korea. The outcome variable was the number of remaining teeth, and its associations with the independent variables of participants’ general characteristics, salivary haemoglobin level, dental biofilm acidogenicity, salivary flow rate and oral hygiene behaviours were assessed. For statistical analyses, chi‐squared test and step‐wise multiple linear regression were used.Results
The multiple linear regression model, which included all related factors identified in the bivariate analyses, showed that older adults who had high salivary haemoglobin levels (P < .05), brushed their teeth using the horizontal scrub method (P< .001), and did not use an interproximal cleaning device (P < .01) were more likely to have fewer remaining teeth. However, dental biofilm acidogenicity was not associated with the number of remaining teeth.Conclusion
The number of remaining teeth was associated with salivary haemoglobin level, appropriate toothbrushing technique and interdental cleaning. These findings suggest that the monitoring of salivary haemoglobin may contribute to the prevention of tooth loss caused by periodontal disease. 相似文献4.
Marco Salerno Luca Giacomelli Giacomo Derchi Niranjan Patra Alberto Diaspro 《Biomedical engineering online》2010,9(1):59
Background
Surface roughness is the main factor determining bacterial adhesion, biofilm growth and plaque formation on the dental surfaces in vivo. Air-polishing of dental surfaces removes biofilm but can also damage the surface by increasing its roughness. The purpose of this study was to investigate the surface damage of different conditions of air-polishing performed in vitro on a recently introduced dental restorative composite. 相似文献5.
Dan Wang Jing Mao Bin Zhou Xiao-Fu Liao Shi-Qiang Gong Yan Liu Jing-Tao Zhang 《Biotechnology letters》2011,33(1):191-197
Purpose of work
Our study provides a promising alternative of biomimetic coating which functionalizes the dental implant with adhesion peptides and may be useful for enhancing the bone remodeling around Ti implants. 相似文献6.
Background
Whole-cell biocatalysis in organic solvents has been widely applied to industrial bioprocesses. In two-phase water-solvent processes, substrate conversion yields and volumetric productivities can be limited by the toxicity of solvents to host cells and by the low mass transfer rates of the substrates from the solvent phase to the whole-cell biocatalysts in water. 相似文献7.
Background
The structure and flexibility of Candida antarctica lipase B in water and five different organic solvent models was investigated using multiple molecular dynamics simulations to describe the effect of solvents on structure and dynamics. Interactions of the solvents with the protein and the distribution of water molecules at the protein surface were examined. 相似文献8.
Brigitte Kunze Michael Reck Andreas Dötsch André Lemme Dietmar Schummer Herbert Irschik Heinrich Steinmetz Irene Wagner-Döbler 《BMC microbiology》2010,10(1):199
Background
Streptococcus mutans is a major pathogen in human dental caries. One of its important virulence properties is the ability to form biofilms (dental plaque) on tooth surfaces. Eradication of such biofilms is extremely difficult. We therefore screened a library of secondary metabolites from myxobacteria for their ability to damage biofilms of S. mutans. 相似文献9.
Pei-Hsun Cheng Brooke Snyder Dimitri Fillos Chris C Ibegbu Anderson Hsien-Cheng Huang Anthony WS Chan 《BMC cell biology》2008,9(1):20
Background
Chimpanzee dental pulp stem/stromal cells (ChDPSCs) are very similar to human bone marrow derived mesenchymal stem/stromal cells (hBMSCs) as demonstrated by the expression pattern of cell surface markers and their multipotent differentiation capability. 相似文献10.
Background
Enzymes show relative instability in solvents or at elevated temperature and lower activity in organic solvent than in water. These limit the industrial applications of enzymes. 相似文献11.
Background
Hair is unique to mammals. Keratin associated proteins (KRTAPs), which contain two major groups: high/ultrahigh cysteine and high glycine-tyrosine, are one of the major components of hair and play essential roles in the formation of rigid and resistant hair shafts. 相似文献12.
Biswendu Chaudhuri Jennifer Rojek M Margaret Vickerman Jason M Tanzer Frank A Scannapieco 《BMC microbiology》2007,7(1):60
Background
Glucosyltransferases (Gtfs), enzymes that produce extracellular glucans from dietary sucrose, contribute to dental plaque formation byStreptococcus gordoniiandStreptococcus mutans. The alpha-amylase-binding protein A (AbpA) ofS. gordonii, an early colonizing bacterium in dental plaque, interacts with salivary amylase and may influence dental plaque formation by this organism. We examined the interaction of amylase and recombinant AbpA (rAbpA), together with Gtfs ofS. gordoniiandS. mutans. 相似文献13.
14.
Frank Schreiber Peter Stief Armin Gieseke Ines M Heisterkamp Willy Verstraete Dirk de Beer Paul Stoodley 《BMC biology》2010,8(1):24
Background
Microbial denitrification is not considered important in human-associated microbial communities. Accordingly, metabolic investigations of the microbial biofilm communities of human dental plaque have focused on aerobic respiration and acid fermentation of carbohydrates, even though it is known that the oral habitat is constantly exposed to nitrate (NO3 -) concentrations in the millimolar range and that dental plaque houses bacteria that can reduce this NO3 - to nitrite (NO2 -). 相似文献15.
16.
17.
Background
Rat liver endosomes contain activated insulin receptors and downstream signal transduction molecules. We undertook these studies to determine whether endosomes also contain heterotrimeric G proteins that may be involved in signal transduction from G protein-coupled receptors. 相似文献18.
Betzaida Castillo Vibha Bansal Ashok Ganesan Peter Halling Francesco Secundo Amaris Ferrer Kai Griebenow Gabriel Barletta 《BMC biotechnology》2006,6(1):51-13
Background
Enzymes have been extensively used in organic solvents to catalyze a variety of transformations of biological and industrial significance. It has been generally accepted that in dry aprotic organic solvents, enzymes are kinetically trapped in their conformation due to the high-energy barrier needed for them to unfold, suggesting that in such media they should remain catalytically active for long periods. However, recent studies on a variety of enzymes demonstrate that their initial high activity is severely reduced after exposure to organic solvents for several hours. It was speculated that this could be due to structural perturbations, changes of the enzyme's pH memory, enzyme aggregation, or dehydration due to water removal by the solvents. Herein, we systematically study the possible causes for this undesirable activity loss in 1,4-dioxane. 相似文献19.
Ranga Partha Melinda Lackey Andreas Hirsch S Ward Casscells Jodie L Conyers 《Journal of nanobiotechnology》2007,5(1):6-11