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Gaps and delays in survivorship care in the return-to-work pathway for survivors of breast cancer-a qualitative study. ACTA ACUST UNITED AC 2019; 26:e414-e417. [PMID: 31285687 DOI: 10.3747/co.26.4787] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Introduction The number of survivors of breast cancer (bca) in Canada has steadily increased thanks to major advances in cancer care. But the resulting clientele face new challenges related to survivorship. The lack of continuity of care and the side effects of treatment affect the resumption of active life by survivors of bca, including return to work (rtw). The goal of the present article was to outline gaps and delay in survivorship care in the rtw pathway of survivors of bca. Methods This qualitative interpretative descriptive study recruited 9 survivors of bca in the province of Quebec. Interviews were conducted at the end of cancer treatments (n = 9), 1 month before rtw (n = 9), and after rtw (n = 5). In an iterative process, a content analysis was performed. Results The interviews highlighted gaps in survivorship care and the paucity of dedicated resources for cancer survivors. Participants received neither a survivorship care plan nor information about cancer survivorship (for example, transition to a new normal, side effects, rtw). Conclusions Support for survivors of bca resuming their active lives has to be optimized. We suggest that health professionals have to intervene at 1, 3, and 6 months after cancer treatment. At those points, survivors of bca need support for side-effects management, the rtw decision, resource navigation, and reintegration of daily activities. Also, delay in clinical pathways seems to be longer, and much attention is needed to accompany the transition to a "normal life" after cancer.
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[The intervention mapping protocol: A structured process to develop, implement and evaluate health promotion programs]. Rev Epidemiol Sante Publique 2016; 64:33-44. [PMID: 26745997 DOI: 10.1016/j.respe.2015.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Revised: 09/21/2015] [Accepted: 10/05/2015] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Health promotion programs are expected to improve population health and reduce social inequalities in health. However, their theoretical foundations are frequently ill-defined, and their implementation faces many obstacles. The aim of this article is to describe the intervention mapping protocol in health promotion programs planning, used recently in several countries. METHODS The challenges of planning health promotion programs are presented, and the six steps of the intervention mapping protocol are described with an example. Based on a literature review, the use of this protocol, its requirements and potential limitations are discussed. RESULTS The intervention mapping protocol has four essential characteristics: an ecological perspective (person-environment), a participative approach, the use of theoretical models in human and social sciences and the use of scientific evidence. It comprises six steps: conduct a health needs assessment, define change objectives, select theory-based change techniques and practical applications, organize techniques and applications into an intervention program (logic model), plan for program adoption, implementation, and sustainability, and generate an evaluation plan. This protocol was used in different countries and domains such as obesity, tobacco, physical activity, cancer and occupational health. Although its utilization requires resources and a critical stance, this protocol was used to develop interventions which efficacy was demonstrated. CONCLUSION The intervention mapping protocol is an integrated process that fits the scientific and practical challenges of health promotion. It could be tested in France as it was used in other countries, in particular to reduce social inequalities in health.
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Potential of Raman Spectroscopy To Monitor Arsenic Toxicity on Bacteria: Insights toward Multiparametric Bioassays. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:12324-12332. [PMID: 26398864 DOI: 10.1021/acs.est.5b03013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In the field of toxicological bioassays, the latest progress in Raman spectroscopy opens new research perspectives on a fast method of observing metabolic responses against toxic agents. This technique offers a multiparametric approach, providing an overview of the physiological changes that are caused by pollutants. However, physiological spectral fingerprints require complex chemometric methods for proper analysis. In this study, particular attention has been given to the elaboration of an "aberrant spectra" detection strategy to highlight the effects of arsenic on the bacteria Escherichia coli. This strategy significantly improved spectra classification, consistent with a dose-response effect of the four tested concentrations of the metal. Indeed, the correct classification score of the spectra increased from 88 to more than 99%. The exposure time effect has also been investigated. The fine analysis of Raman spectroscopy fingerprints enabled the design of different "spectral signatures", highlighting early and late effects of arsenic on bacteria. The observed variations are in agreement with the expected toxicity and encourage the use of Raman spectroscopy for toxic element detection.
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Detection of Metal and Organometallic Compounds with Bioluminescent Bacterial Bioassays. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015:77-99. [PMID: 26475470 DOI: 10.1007/10_2015_332] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Chemical detection of metal and organometallic compounds is very specific and sensitive, but these techniques are time consuming and expensive. Although these techniques provide information about the concentrations of compounds, they fail to inform us about the toxicity of a sample. Because the toxic effects of metals and organometallic compounds are influenced by a multitude of environmental factors, such as pH, the presence of chelating agents, speciation, and organic matter, bioassays have been developed for ecotoxicological studies. Among these bioassays, recombinant luminescent bacteria have been developed over the past 20 years, and many of them are specific for the detection of metals and metalloids. These bioassays are simple to use, are inexpensive, and provide information on the bioavailable fraction of metals and organometals. Thus, they are an essential complementary tool for providing information beyond chemical analysis. In this chapter, we propose to investigate the detection of metals and organometallic compounds with bioluminescent bacterial bioassays and the applications of these bioassays to environmental samples. Graphical Abstract.
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Main Technological Advancements in Bacterial Bioluminescent Biosensors Over the Last Two Decades. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015:101-116. [PMID: 26475467 DOI: 10.1007/10_2015_333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Environmental quality assessment is an extensive field of research due to the permanent increase of the stringency imposed by the legislative framework. To complete the wide panel of measurement methods, essentially based on physicochemical tools, some scientists focused on the development of alternative biological methods such as those based on the use of bioluminescent bacteria biosensors. The first report dedicated to the development of such biosensors dates back to 1967 and describes an analytical system designed to address the problem of air toxicity assessment. Nevertheless the available technologies in the photosensitive sensors field were not mature enough and, as a result, limited biosensor development possibilities. For about 20 years, the wide democratisation of photosensors coupled with advances in the genetic engineering field have allowed the expansion of the scope of possibilities of bioluminescent bacterial biosensors, allowing a significant emergence of these biotechnologies. This chapter retraces the history of the main technological evolutions that bacterial bioluminescent biosensors have known over the last two decades. Graphical Abstract.
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Methods for assessing biochemical oxygen demand (BOD): a review. WATER RESEARCH 2014; 49:62-82. [PMID: 24316182 DOI: 10.1016/j.watres.2013.10.066] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 10/21/2013] [Accepted: 10/25/2013] [Indexed: 05/13/2023]
Abstract
The Biochemical Oxygen Demand (BOD) is one of the most widely used criteria for water quality assessment. It provides information about the ready biodegradable fraction of the organic load in water. However, this analytical method is time-consuming (generally 5 days, BOD5), and the results may vary according to the laboratory (20%), primarily due to fluctuations in the microbial diversity of the inoculum used. Work performed during the two last decades has resulted in several technologies that are less time-consuming and more reliable. This review is devoted to the analysis of the technical features of the principal methods described in the literature in order to compare their performances (measuring window, reliability, robustness) and to identify the pros and the cons of each method.
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New insights into polyurethane biodegradation and realistic prospects for the development of a sustainable waste recycling process. Biotechnol Adv 2013; 31:1634-47. [PMID: 23978675 DOI: 10.1016/j.biotechadv.2013.08.011] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 07/31/2013] [Accepted: 08/15/2013] [Indexed: 10/26/2022]
Abstract
Polyurethanes are polymeric plastics that were first used as substitutes for traditional polymers suspected to release volatile organic hazardous substances. The limitless conformations and formulations of polyurethanes enabled their use in a wide variety of applications. Because approximately 10 Mt of polyurethanes is produced each year, environmental concern over their considerable contribution to landfill waste accumulation appeared in the 1990s. To date, no recycling processes allow for the efficient reuse of polyurethane waste due to their high resistance to (a)biotic disturbances. To find alternatives to systematic accumulation or incineration of polyurethanes, a bibliographic analysis was performed on major scientific advances in the polyurethane (bio)degradation field to identify opportunities for the development of new technologies to recondition this material. Until polymers exhibiting oxo- or hydro-biodegradative traits are generated, conventional polyurethanes that are known to be only slightly biodegradable are of great concern. The research focused on polyurethane biodegradation highlights recent attempts to reprocess conventional industrial polyurethanes via microbial or enzymatic degradation. This review describes several wonderful opportunities for the establishment of new processes for polyurethane recycling. Meeting these new challenges could lead to the development of sustainable management processes involving polymer recycling or reuse as environmentally safe options for industries. The ability to upgrade polyurethane wastes to chemical compounds with a higher added value would be especially attractive.
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A simple method of surface functionalisation for immuno-specific immobilisation of proteins. Anal Bioanal Chem 2010; 398:1249-55. [PMID: 20683585 DOI: 10.1007/s00216-010-4032-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 07/07/2010] [Accepted: 07/13/2010] [Indexed: 11/25/2022]
Abstract
We present a new and advanced methodology, developed for surface functionalisation of gold and to study immobilisation of an immuno-specific system of proteins. A combination of electrochemical quartz crystal microbalance and Raman spectroscopy techniques allowed a complete understanding of the system starting from surface functionalisation and progressing to the functional structure analysis of immobilised proteins. A simple electrochemical procedure was formulated to prepare sulphonyl chloride terminated gold surfaces that form a strong sulphonamide bond with the receptor protein staphylococcal protein A (SpA). On the SpA grafted surfaces, the immobilisation of a human IgG and consecutive binding of an immuno-specific anti-human IgG was observed. The surface functional groups form a strong interaction with SpA without disturbing its functional properties. The native functional structure of SpA and also the IgGs was found to be retained in their immobilised state.
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Margin of manoeuvre indicators in the workplace during the rehabilitation process: a qualitative analysis. JOURNAL OF OCCUPATIONAL REHABILITATION 2009; 19:194-202. [PMID: 19333737 DOI: 10.1007/s10926-009-9173-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Accepted: 03/12/2009] [Indexed: 05/27/2023]
Abstract
INTRODUCTION The task of evaluating workers' capacity to return to their pre-injury employment or other jobs continues to pose a daily challenge for clinicians. In this study, a concept frequently used in the field of ergonomics, the margin of manoeuvre (MM), was applied during the rehabilitation process. The study identified the indicators of the MM taken into account during the return to work of workers with musculoskeletal disorders. METHODS This study used a multiple-case design. A case was defined as a dyad comprising a worker admitted to a work rehabilitation program and the clinician who was managing the return-to-work process. The results were then validated with investigators and expert ergonomists, through group interviews. Content analyses were performed using the conceptual framework for the work activity model adapted from Vézina and the procedures recommended by Miles and Huberman. RESULTS A total of 11 workers, five clinicians, two experts and two investigators participated in this study. The interview analysis process resulted in a more detailed definition of the MM and the identification of 50 indicators. The indicators were classified according to six dimensions: (1) work context; (2) employer's requirements and expectations; (3) means and tools; (4) worker's personal parameters; (5) work activity; and (6) impacts of the work situation. CONCLUSIONS The more specific indicators identified in this study will allow for more systematic observation of the MM. Subsequent studies will seek to link each indicator described in the model with a specific method of observation.
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Relationships between intertidal clam population and health status of the soft-shell clam Mya arenaria in the St. Lawrence Estuary and Saguenay Fjord (Québec, Canada). ENVIRONMENT INTERNATIONAL 2008; 34:30-43. [PMID: 17825412 DOI: 10.1016/j.envint.2007.06.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Revised: 06/20/2007] [Accepted: 06/21/2007] [Indexed: 05/17/2023]
Abstract
The purpose of this study was to examine the impacts of anthropogenic activity on the health status of intertidal clam populations of the Saguenay Fjord and the St. Lawrence Estuary (Québec, Canada). Clams were collected during low tide at sites subject to direct contamination and at sites far from human activity. Clams were analyzed for tributyltin and dibutyltin total levels and toxic stress (glutathione S-transferase, gonadal lipid peroxidation and DNA strand breaks), immunocompetence (phagocytic activity, hemocyte count and viability), reproduction (gonado-somatic index, gamete maturation, and vitellogenin-like proteins), energy status (temperature-dependent mitochondrial electron transport, and gonad lipids), and individual status (age, condition factor, and growth index). These responses were compared against population characteristics such as live clam density, number of empty shells, and sex ratio. The results show that clam density decreased with distance from the estuary (high salinity level) to upstream of the fjord (low salinity). There was no clear relationship between the number of empty shells and distance or site quality. Clam density values corrected against distance were significantly correlated with hemocyte viability, phagocytic activity, mitochondrial electron transport (MET), DNA damage in gonad, and temperature-dependent mitochondrial electron transport activity. A canonical analysis of the various groups of biomarkers revealed that population metrics were more strongly related with immunocompetence, followed by energy status and temperature-dependent mitochondrial electron transport activity. However, toxic stress biomarkers were strongly associated with energy status and reproduction. This was further confirmed by non-linear modeling using adaptive artificial neural networks (genetic selection and back propagation learning paradigms), where the following parameters were able to predict population parameters with <20% error: gonad maturation and somatic index, MET (at 4 degrees C), gonad LPO, DNA damage, and phagocytic capacity. Intertidal clam populations were influenced by a distance gradient effect (salinity), where immunocompetence, in addition to energy status, was the strongest physiological parameter related to clam population metrics.
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Workplace interventions for workers with musculoskeletal disabilities: a descriptive review of content. JOURNAL OF OCCUPATIONAL REHABILITATION 2007; 17:123-36. [PMID: 16967333 DOI: 10.1007/s10926-006-9036-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
BACKGROUND Despite the convergence of scientific data to the effect that interventions in the workplace promote a healthy return to work, the interventions carried out in the real work environment appear to be very heterogeneous and ill-defined. OBJECTIVE The goal of this review is to identify the different objectives pursued through the workplace interventions carried out in the context of a rehabilitation program, and to describe the activities involved. METHODS A descriptive review of the literature, including various research designs, was carried out. RESULTS This review reveals great heterogeneity in the content of interventions offered in the workplace to workers with musculoskeletal disabilities. The objectives of workplace interventions may range from gathering information in order to reproduce work demands in a clinical setting, to gradually exposing workers to the demands of the real work environment, or permanently reducing the demands of the work situation. A descriptive analysis of the literature also brings to light the diversity of actions carried out, human resources used, and workplace environments involved, while highlighting the few documented process outcome evaluations that have been done of workplace interventions. CONCLUSION It is recommended that in future research in this area, efforts be made to better describe the components of the interventions, to develop process outcomes representing the multidimensional results obtained in the workplace, and to differentiate between temporary and permanent modifications made to the work situation.
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Measurement properties of a new quality of life measure for patients with work disability associated with musculoskeletal pain. JOURNAL OF OCCUPATIONAL REHABILITATION 2005; 15:295-312. [PMID: 16119222 DOI: 10.1007/s10926-005-5938-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
INTRODUCTION The Quality of Life Systemic Inventory (QLSI) measures patients' goal attainment based on the system control theory. It quantifies the perceived impact of the disorder and the gap between the present and aspired states. PURPOSE To evaluate concurrent validity and responsiveness of the QLSI among workers on sick leave due to musculoskeletal disorders (MSDs). METHODS Participants (10 women; 29 men) were recruited at a work rehabilitation centre and had more than 4 weeks of absence from work due to MSDs compensated by the Workers' Compensation Board. Concurrent validity and external responsiveness were based on baseline and post-treatment measures of external criteria. Criteria and related instruments were the following: perception of disability (Roland-Morris Disability Questionnaire); health-related quality of life (SF-12); stress (Psychological Stress Measure) and distress (Psychological Distress Index). RESULTS Regression analyses revealed significant correlations between QLSI scores and the Psychological Distress Index (r2 = .11 to .19 and .66; p < .001), with either the SF-12 mental component scale (r2 = .18 and .11; p < .01) or the Roland-Morris Disability Questionnaire (r2 = .04 and .10; p < .05). All measures showed highly significant change over time. CONCLUSION Results support the concurrent validity and responsiveness of the QLSI, with an MSD population. SIGNIFICANCE This instrument could serve in future research as an outcome measurement instrument in the evaluation of more long-term effects of rehabilitation programs.
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Development of a biosensor for on-line detection of tributyltin with a recombinant bioluminescent Escherichia coli strain. Appl Microbiol Biotechnol 2003; 62:218-25. [PMID: 12883867 DOI: 10.1007/s00253-003-1279-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2002] [Revised: 02/05/2003] [Accepted: 02/05/2003] [Indexed: 11/30/2022]
Abstract
A biosensor was developed for the detection of tributyltin (TBT), using a bioluminescent recombinant Escherichia coli:: luxAB strain. Dedicated devices allowed the on-line measurement of bioluminescence, pH and dissolved oxygen values and the feed-back regulation of temperature. Bacterial physiology was monitored by the measurement of the cellular density, respiratory activity and the intracellular level of ATP, glucose and acetate levels. Our results showed that a synthetic glucose medium gave a better TBT detection limit than LB medium (respectively 0.02 micro M and 1.5 micro M TBT). High growth and dilution rates ( D=0.9 h(-1)) allowed maximum light emission from the bacterium. Moreover, simple atmospheric air bubbling was sufficient to provide oxygen for growth and the bioluminescence reaction. Real-time monitoring of bioluminescence after TBT induction occurred with continuous addition of decanal up to 300 micro M, which was not toxic throughout a 7-day experiment. The design of our biosensor and the optimization of the main parameters that influence microbial activity led to the capacity for the detection of TBT.
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Cost-benefit and cost-effectiveness analysis of a disability prevention model for back pain management: a six year follow up study. Occup Environ Med 2002; 59:807-15. [PMID: 12468746 PMCID: PMC1763600 DOI: 10.1136/oem.59.12.807] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To test the long term cost-benefit and cost-effectiveness of the Sherbrooke model of management of subacute occupational back pain, combining an occupational and a clinical rehabilitation intervention. METHODS A randomised trial design with four arms was used: standard care, occupational arm, clinical arm, and Sherbrooke model arm (combined occupational and clinical interventions). From the Quebec WCB perspective, a cost-benefit (amount of consequence of disease costs saved) and cost-effectiveness analysis (amount of dollars spent for each saved day on full benefits) were calculated for each experimental arm of the study, compared to standard care. RESULTS At the mean follow up of 6.4 years, all experimental study arms showed a trend towards cost benefit and cost effectiveness. These results were owing to a small number of very costly cases. The largest number of days saved from benefits was in the Sherbrooke model arm. CONCLUSIONS A fully integrated disability prevention model for occupational back pain appeared to be cost beneficial for the workers' compensation board and to save more days on benefits than usual care or partial interventions. A limited number of cases were responsible for most of the long term disability costs, in accordance with occupational back pain epidemiology. However, further studies with larger samples will be necessary to confirm these results.
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Alteration in methyl-methanesulfonate-induced poly(ADP-ribosyl)ation by 2-butoxyethanol in Syrian hamster embryo cells. Carcinogenesis 1997; 18:2333-8. [PMID: 9450478 DOI: 10.1093/carcin/18.12.2333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The effects of 2-butoxyethanol (2-BE) on poly(ADP-ribosyl)ation were studied in Syrian hamster embryo (SHE) cells by measuring the cellular concentrations of the polymer poly(ADP-ribose) (pADPr) and of NAD+, the substrate of poly(ADP-ribose) polymerase (PARP). As biotransformation pathways of ethylene glycol ethers involve NAD+-dehydrogenases, it was hypothesized that 2-BE could reduce poly(ADP-ribosyl)ation by consuming NAD+. As a result DNA repair could be altered, which would explain that 2-BE had been shown to potentiate the effects of clastogenic substances such as methyl-methanesulfonate (MMS). In this study, the effects of 2-BE on MMS-induced pADPr metabolism were analyzed. The results indicated that: (i) 2-BE (5 mM) by itself did not influence significantly pADPr or NAD+ levels. (ii) 2-BE inhibited pADPr synthesis in MMS (0.2 mM)-pretreated cells, without any change in NAD+ concentrations. (iii) MMS treatment, which rapidly increased pADPr levels, also affected the poly(ADP-ribosyl)ation system as a secondary effect by damaging cell structures. Membrane permeabilization, which occurred at concentrations >1 mM MMS, led to a dramatic leakage of cellular NAD+ resulting in a strong reduction in pADPr levels. (iv) A bleomycin pulse (100 microM) applied after MMS and/or 2-BE treatment confirmed that 2-BE reduced poly(ADP-ribosyl)ation capacities of MMS-treated cells, though the glycol ether had no effect alone. This study confirmed that the inhibition of pADPr synthesis could be responsible for the synergistic effects of 2-BE with genotoxic substances. The mechanism of this inhibition cannot be explained by a lack of NAD+ at the concentrations of 2-BE tested.
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Comparative effects of clofibrate and methyl clofenapate on morphological transformation and intercellular communication of Syrian hamster embryo cells. Carcinogenesis 1997; 18:701-6. [PMID: 9111203 DOI: 10.1093/carcin/18.4.701] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The Syrian hamster embryo (SHE) cell system was used to evaluate the ability of two hepatocarcinogenic structurally related peroxisome proliferators (PPs) to induce morphological transformation (MT) of SHE colonies and to inhibit gap junctional intercellular communication (GJIC). Clofibrate and methyl clofenapate (MCP), which was shown to be a more active PP and a more potent carcinogen in vivo than clofibrate, were compared. MCP appeared slightly more active in vitro than clofibrate in affecting MT and GJIC of SHE cells. The morphological transformation of SHE colonies was induced by 50 microM MCP, against 100 microM clofibrate. Moreover, 50 microM MCP potentiated the transforming effects of both benzo[a]pyrene and 12-O-tetradecanoylphorbol-13-acetate. The inhibition of GJIC, measured by transfer of lucifer yellow, was transient and occurred at concentrations inducing morphological transformation. MCP inhibited dye transfer at 50 microM and the inhibition lasted up to 24 h at 100 microM. Inhibition of communication lasted only 4 h with clofibrate and occurred at a higher concentration (175 microM). This study showed that both the SHE cell transformation and dye transfer assays were able to display the different activities of the two PPs, even though the difference in potency observed was smaller than in vivo. It also revealed interactions between non-genotoxic carcinogens and the ability of the SHE cell transformation assay to detect these combined effects.
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Correlating increased ocular and systemic blood pressures with neuroretinal function. AVIATION, SPACE, AND ENVIRONMENTAL MEDICINE 1996; 67:1174-8. [PMID: 8968485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND The microgravity environment of spaceflights alters the systemic circulation, decreasing the peripheral resistance, while increasing the heart rate and systemic blood pressure. HYPOTHESIS Body orientation simulating fluid shifts associated with microgravity during spaceflights affects the neural retinal function. METHODS Fifteen healthy adults between 18 and 26 yr of age participated in this study. Scotopic flash electroretinograms and oscillatory potentials were compared for: 1) baseline, wherein subjects were declined 30 degrees from vertical; and 2) for microgravity simulation where subjects were in a 7 degrees head down tilt for 90 min. RESULTS Group averaged implicit times for the ERG b-wave, as well as OP3, OP4 and OP5 were prolonged after microgravity simulation, and the group averaged OP index was reduced. CONCLUSIONS The results suggest that microgravity of relatively short duration may cause retinal ischemia manifest as neuroretinal dysfunction with yet undetermined effects on visual and overall performance.
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Preparation of compound-specific and group-specific antibodies to 7-methylguanine and related 7-alkylguanines and their use in immunoaffinity purification. Carcinogenesis 1994; 15:957-61. [PMID: 8200101 DOI: 10.1093/carcin/15.5.957] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The preparation and characteristics of compound-specific and group-specific antibodies against 7-alkylguanines (7-alkGua) are described. A compound-specific antibody against 7-methylguanine was prepared using a hapten bound to carrier protein through the N2 position. In a competitive enzyme-linked immunosorbent assay (ELISA) 7-methylguanine (7-MeGua) showed 50% inhibition (I50%) at 10 pmol/well at room temperature, but the inhibition was found to be 40 times better at 4 degrees C (I50% at 250 fmol/well). When the antibody was bound to protein A-Sepharose CL4B 7-MeGua was retained in immunoaffinity columns. A group-specific antibody to 7-alkGua was prepared using 7-(2-carboxyethyl)guanine (7-CEGua) bound to carrier protein via the carboxyl group. In a competitive ELISA, this antibody cross-reacted well with 7-CEGua, 7-ethylguanine (7-EtGua), 7-(2-hydroxyethyl)guanine (7-HOEtGua) and 7-(2',3'-dihydroxy)-propylguanine (7-DHPGua) and some inhibition was seen with 7-MeGua. Immunoaffinity columns prepared from this antibody retained a number of 7-alkGua of diverse structure. 7-EtGua in calf thymus DNA treated with diethylsulphate and ethylnitrosourea was isolated by immunoaffinity purification and quantified by HPLC-fluorescence. These results illustrate the potential of immunoaffinity purification for both individual DNA adducts and groups of adducts.
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Effects of TENS and topical skin anesthesia on soleus H-reflex and the concomitant influence of skin/muscle temperature. Arch Phys Med Rehabil 1993; 74:48-53. [PMID: 8420520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The purpose of this study was to determine, in ten healthy subjects, the extent of soleus motoneuronal excitability during conditions of increased (transcutaneous electrical nerve stimulation [TENS]), decreased (Xylocaine [lidocaine]a anaesthesia) and normal (placebo anaesthesia) cutaneous inputs. Increased cutaneous activity was evoked using a TENS unit, with the two pairs of electrodes placed respectively over the Achilles (S2 dermatome) and tibialis anterior (L5 dermatome) tendons. Experimental and placebo topical anaesthesia were obtained after rubbing Xylocaine (5%) and Vaselineb ointment, respectively, on the skin surface overlying the Achilles tendon. Sets of ten H-responses (Hmax/2) were evoked at a frequency of 1 shock/30s and averaged at regular time intervals before, during and after the testing conditions. The results showed a gradual increase (up to 40% after 20 minutes) of H-reflex amplitude during TENS regardless of whether it was applied on the L5 or S2 dermatome. Furthermore, placebo anesthesia (Vaseline) caused the same gradual facilitatory response (up to 100% after 50 minutes) as that obtained during Xylocaine anaesthesia. Power spectral analysis of the H-responses obtained over time showed that the increase in the peak-to-peak H-response value was accompanied by a shift of the spectral content toward low frequencies. This shift occurred concomitantly with a cooling of the skin overlying the soleus muscle.
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[Effect of bronchitis in the aged on serum gamma glutamyl transpeptidase activity]. LILLE MEDICAL : JOURNAL DE LA FACULTE DE MEDECINE ET DE PHARMACIE DE L'UNIVERSITE DE LILLE 1974; 19:749-51. [PMID: 4155466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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