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991.
Gerhard Scherer Michael Urban Johannes Engl Heinz-Werner Hagedorn Kirsten Riedel 《Inhalation toxicology》2013,25(10):821-829
Charcoal (CC) filters of cigarettes are known to significantly reduce a series of volatile constituents in mainstream smoke, including reactive α,β-unsaturated aldehydes such as acrolein and crotonaldehyde. We performed a randomized, crossover, 2-wk brand-switching study with 39 smokers. Twenty of the subjects smoked cellulose acetate (CA) filter tipped cigarettes during wk 1 of the study; the remaining 19 subjects smoked CC filter tipped cigarettes during wk 1. In wk 2, the subjects switched to the corresponding brand with the other filter type, with similar smoking machine-derived tar and nicotine yields. Daily cigarette consumption, carbon monoxide in exhaled breath, salivary cotinine, and urinary nicotine equivalents (molar sum of nicotine plus five major metabolites) did not change significantly when switching to the cigarettes with the other filter type. Urinary excretion rates of 3-hydroxy-1-methylpropylmercapturic acid (metabolite of crotonaldehyde), monohydroxybutenylmercapturic acid (metabolite of 1,3-butadiene), and S-phenylmercapturic acid (metabolite of benzene) were significantly lower when smoking CC compared to CA filter tipped cigarettes. The reduction in amount of 3-hydroxypropylmercapturic acid (metabolite of acrolein) was of borderline significance. Other mercapturic acids and thioethers (the latter is a summary parameter that indicates the exposure to electrophilic compounds) were not or were only slightly reduced upon smoking CC filter tipped cigarettes. We conclude that smoking CC filter tipped cigarettes does not change the uptake of carbon monoxide and nicotine when compared to CA filter tipped cigarettes with similar tar and nicotine yields, but significantly reduces the exposure to toxicologically relevant smoke constituents such as acrolein, crotonaldehyde, 1,3-butadiene, and benzene. 相似文献
992.
Alison C. Scherer Ami Tsuchiya Lisa R. Younglove Thomas M. Burbacher Elaine M. Faustman 《Environmental health perspectives》2008,116(12):1598-1606
Objective
Fish consumption advisories are issued to warn the public of possible toxicological threats from consuming certain fish species. Although developing fetuses and children are particularly susceptible to toxicants in fish, fish also contain valuable nutrients. Hence, formulating advice for sensitive populations poses challenges. We conducted a comparative analysis of advisory Web sites issued by states to assess health messages that sensitive populations might access.Data sources
We evaluated state advisories accessed via the National Listing of Fish Advisories issued by the U.S. Environmental Protection Agency.Data extraction
We created criteria to evaluate advisory attributes such as risk and benefit message clarity.Data synthesis
All 48 state advisories issued at the time of this analysis targeted children, 90% (43) targeted pregnant women, and 58% (28) targeted women of childbearing age. Only six advisories addressed single contaminants, while the remainder based advice on 2–12 contaminants. Results revealed that advisories associated a dozen contaminants with specific adverse health effects. Beneficial health effects of any kind were specifically associated only with omega-3 fatty acids found in fish.Conclusions
These findings highlight the complexity of assessing and communicating information about multiple contaminant exposure from fish consumption. Communication regarding potential health benefits conferred by specific fish nutrients was minimal and focused primarily on omega-3 fatty acids. This overview suggests some lessons learned and highlights a lack of both clarity and consistency in providing the breadth of information that sensitive populations such as pregnant women need to make public health decisions about fish consumption during pregnancy. 相似文献993.
C Leelawat W Scherer J Chang A Schulman T Vijayaraghavan 《Journal of esthetic dentistry》1992,4(2):41-45
The purpose of this in vitro study was to determine whether adhesive lining materials reduce microleakage in amalgam restorations, and to observe the degree of microleakage at the interface between freshly placed (new) and existing (old) amalgam. Forty-eight specimens were used in the experimental groups. The materials used to study microleakage in this investigation were: copal varnish, a dentin bonding agent (Clearfil New Bond), and a 4-META adhesive (Amalgambond). No significant difference in microleakage was found at the interfaces between freshly placed and existing amalgam. Significantly less microleakage was noted in specimens using the 4-META adhesive and the dentin bonding agent as compared to specimens in which no lining material was placed. Significantly less microleakage was noted in specimens using the 4-META adhesive compared to specimens using cavity varnish. 相似文献
994.
995.
Roger O. Smith Marcia J. Scherer Rory Cooper Diane Bell David A. Hobbs Cecilia Pettersson 《Disability and rehabilitation. Assistive technology》2018,13(5):473-485
AbstractThis paper is based on work from the Global Research, Innovation, and Education on Assistive Technology (GREAT) Summit that was coordinated by WHO’s Global Cooperation on Assistive Technology (GATE). The purpose of this paper is to describe the needs and opportunities embedded in the assistive product lifecycle as well as issues relating to the various stages of assistive product mobilization worldwide.The paper discusses assistive technology product terminology and the dangers of focusing on products outside the context and rolling out products without a plan. Additionally, the paper reviews concepts and issues around technology transfer, particularly in relation to meeting global needs and among countries with limited resources. Several opportunities are highlighted including technology advancement and the world nearing a state of readiness through a developing capacity of nations across the world to successfully adopt and support the assistive technology products and applications.The paper is optimistic about the future of assistive technology products reaching the people that can use it the most and the excitement across large and small nations in increasing their own capacities for implementing assistive technology. This is expressed as hope in future students as they innovate and in modern engineering that will enable assistive technology to pervade all corners of current and potential marketplaces. Importantly, the paper poses numerous topics where discussions are just superficially opened. The hope is that a set of sequels will follow to continue this critical dialog.
- Implications for Rehabilitation
Successful assistive technology product interventions are complex and include much more than the simple selection of the right product.
Assistive technology product use is highly context sensitive in terms of an individual user’s environment.
The development of assistive technology products is tricky as it must be contextually sensitive to the development environment and market as well.
As a field we have much to study and develop around assistive technology product interventions from a global perspective.
996.
Debora Melo van Lent Sarah Egert Steffen Wolfsgruber Luca Kleineidam Leonie Weinhold Holger Wagner-Thelen Wolfgang Maier Frank Jessen Alfredo Ramirez Matthias Schmid Martin Scherer Steffi G. Riedel-Heller Michael Wagner 《Nutrients》2021,13(2)
Background. Omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) may have different effects on cognitive health due to their anti- or pro-inflammatory properties. Methods. We aimed to prospectively examine the relationships between n-3 and n-6 PUFA contents in serum phospholipids with incident all-cause dementia and Alzheimer’s disease dementia (AD). We included 1264 non-demented participants aged 84 ± 3 years from the German Study on Ageing, Cognition, and Dementia in Primary Care Patients (AgeCoDe) multicenter-cohort study. We investigated whether fatty acid concentrations in serum phospholipids, especially eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), alpha-linolenic acid (ALA), linoleic acid (LA), dihomo-γ-linolenic acid (DGLA), and arachidonic acid (AA), were associated with risk of incident all-cause dementia and AD. Results. During the follow-up window of seven years, 233 participants developed dementia. Higher concentrations of EPA were associated with a lower incidence of AD (hazard ratio (HR) 0.76 (95% CI 0.63; 0.93)). We also observed that higher concentrations of EPA were associated with a decreased risk for all-cause dementia (HR 0.76 (95% CI 0.61; 0.94)) and AD (HR 0.66 (95% CI 0.51; 0.85)) among apolipoprotein E ε4 (APOE ε4) non-carriers but not among APOE ε4 carriers. No other fatty acids were significantly associated with AD or dementia. Conclusions. Higher concentrations of EPA were associated with a lower risk of incident AD. This further supports a beneficial role of n-3 PUFAs for cognitive health in old age. 相似文献
997.
Ana Claudia Hertel Pereira Dominik Lenz Breno Valentim Nogueira Rodrigo Scherer Tadeu Uggere Andrade Helber Barcellos da Costa 《Pharmaceutical biology》2017,55(1):472-480
Context: The resin from the trunk wood of Virola oleifera (Schott) A. C. Smith (Myristicaceae) is used in folk medicine to hasten wound repair and to treat pain and inflammatory conditions, and our previous report indicated the anti-oxidative properties in other oxidative stress model.Objective: To investigate the protective effects of resin from V. oleifera in two experimental models of gastric ulcer oxidative-stress dependent.Materials and methods: Plant material was collected and the resin was subjected to partitioning with organic solvents. The buthanol fraction was subjected to chromatographic and spectrometric methods for isolation and structural elucidation. The resin was quantified for polyphenols and flavonoids by colorimetric methods. Furthermore, the antioxidant activity of resin was determined by three different methods. The ulcers were induced acutely in Swiss male mice with ethanol/HCl and indomethacin using single-doses of 10 and 100?mg/kg. The gastroprotection of the experimental groups was comparable to reference control lansoprazole (3?mg/kg).Results: The high content of polyphenols (~82%) and the presence of epicatechin and eriodictyol were determined. The LD50 was estimated at 2500?mg/kg. At minimum (10?mg/kg) and maximum (100?mg/kg) dosage of resin, both in ethanol/HCl as indomethacin ulcer induction models demonstrate reduction of lesions (minimum: ~97% and ~66%; maximum: ~95% and ~59%).Discussion: The gastroprotection might be related to tannins, phenolic acids and flavonoids present in the resin by antioxidant properties.Conclusions: The results indicate that this resin has gastroprotective activity probably associated with the presence of phenolic antioxidant substances. 相似文献
998.
Samuel C Scherer Jeanette Rule Melanie Fischer Elizabeth Jacobs Lois Dobson Heather De La Rue Michael Browning Josephine Duffus Stephen J Gibson Peteris Darzins 《Australasian journal on ageing》2007,26(4):201-204
Insomnia is common in nursing home settings but assessment and management of sleep disturbance is often suboptimal. New assessment procedures that target potentially remediable clinical causes of insomnia were implemented and evaluated at two high level residential aged care Facilities (HLRACFs) (formerly called nursing homes), in Melbourne, Australia. Fifty‐eight of 147 residents (39%) who complained of insomnia, or were nominated by nursing staff as having disturbed sleep, and had confirmation of sleep disturbance on overnight sleep log, were provided with a structured assessment protocol. A multidisciplinary team then considered the causes of each resident's insomnia. A potentially remediable medical or psychiatric cause was identified in 66% of residents with insomnia. More than one such factor was identified in 34%. Pain was a likely factor in 39%. Depression was a likely factor in 30%. Insomnia, depression and pain were significantly correlated. 相似文献
999.
F Laezza BR Gerber JY Lou MA Kozel H Hartman AM Craig DM Ornitz JM Nerbonne 《The Journal of neuroscience》2007,27(44):12033-12044
Fibroblast growth factor 14 (FGF14) belongs to the intracellular FGF homologous factor subfamily of FGF proteins (iFGFs) that are not secreted and do not activate tyrosine kinase receptors. The iFGFs, however, have been shown to interact with the pore-forming (alpha) subunits of voltage-gated Na+ (Na(v)) channels. The neurological phenotypes seen in Fgf14-/- mice and the identification of an FGF14 missense mutation (FGF14(F145S)) in a Dutch family presenting with cognitive impairment and spinocerebellar ataxia suggest links between FGF14 and neuronal functioning. Here, we demonstrate that the expression of FGF14(F145S) reduces Na(v) alpha subunit expression at the axon initial segment, attenuates Na(v) channel currents, and reduces the excitability of hippocampal neurons. In addition, and in contrast with wild-type FGF14, FGF14(F145S) does not interact directly with Na(v) channel alpha subunits. Rather, FGF14(F145S) associates with wild-type FGF14 and disrupts the interaction between wild-type FGF14 and Na(v) alpha subunits, suggesting that the mutant FGF14(F145S) protein acts as a dominant negative, interfering with the interaction between wild-type FGF14 and Na(v) channel alpha subunits and altering neuronal excitability. 相似文献
1000.