Perceptions of barriers and levers of health-enhancing physical activity policies in mid-size French municipalities.

BACKGROUND: Policy is one of the levers for initiating structural change to foster the promotion of health-enhancing physical activity (HEPA). To this end, policy-makers have to deal with complex ecosystems embedded in specific contexts. However, limited research has been conducted on this topic at the local level. The purpose of this study was to identify the perceived barriers and levers of HEPA policies according to department heads and elected officials across various sectors in mid-size French municipalities. METHODS: This study used a mixed method primarily based on an adaptation of the concept mapping approach. A list of statements completing the sentence: 'In a mid-size municipal context, to develop HEPA policies, it is necessary to …' was submitted to key informants of 17 mid-sized French cities. Key informants in each municipality first rated the importance of each statement without considering their local context; they then rated the feasibility of each statement given their local context. In both cases, they used a Likert scale ranging from 1 to 6. RESULTS: A total of 23 municipal department heads and 10 elected officials from the sport (n = 14), health (n = 10) and social (n = 9) sectors in 11 mid-size French cities participated in this study. A list of 84 statements, sorted into 16 categories, was rated by participants according to their importance (M = 4.52, SD = 0.86) and their feasibility (M = 3.77, SD = 0.74). Potential barriers to (n = 10) and levers of (n = 38) HEPA policy development were identified. These results varied according to the position and sector of the participants. CONCLUSIONS: The results suggest that local contextual factors can affect the development of HEPA policies in mid-size French municipalities. The different perceptions of the potential levers and barriers according to sector might affect intersectoral collaboration. This study contributes by enhancing understanding of how local HEPA policies are developed in the French context.

Cancer mutations and targeted drugs can disrupt dynamic signal encoding by the Ras-Erk pathway.

The Ras-Erk (extracellular signal-regulated kinase) pathway encodes information in its dynamics; the duration and frequency of Erk activity can specify distinct cell fates. To enable dynamic encoding, temporal information must be accurately transmitted from the plasma membrane to the nucleus. We used optogenetic profiling to show that both oncogenic B-Raf mutations and B-Raf inhibitors can cause corruption of this transmission, so that short pulses of input Ras activity are distorted into abnormally long Erk outputs. These changes can reshape downstream transcription and cell fates, resulting in improper decisions to proliferate. These findings illustrate how altered dynamic signal transmission properties, and not just constitutively increased signaling, can contribute to cell proliferation and perhaps cancer, and how optogenetic profiling can dissect mechanisms of signaling dysfunction in disease.

Effect of vicanicin and protolichesterinic acid on human prostate cancer cells: role of Hsp70 protein.

With the aim of identifying novel agents with antigrowth and pro-apoptotic activity on prostate cancer cells, in the present study, we evaluated the effect of five lichen secondary metabolites the depsides atranorin (1), diffrattaic (2) and divaricatic (3) acids, the depsidone vicanicin (4) and the protolichesterinic acid (5) on cell growth in androgen-sensitive (LNCaP) and androgen-insensitive (DU-145) human prostate cancer cells. The cell viability was measured using MTT assay. LDH release, a marker of membrane breakdown, was also measured. For the detection of apoptosis, the evaluation of DNA fragmentation (COMET assay) and caspase-3 activity assay were employed. The expression of Bcl-2, Bax, TRAIL, COX-2, NOS2 and Hsp70 proteins was detected by western blot analysis. Generation of reactive oxygen species was measured by using a fluorescent probe. It was observed that atranorin (1), diffrattaic (2) and divaricatic (3) acids showed a lower activity inhibiting the prostate cancer cells only at more high concentrations (25 and 50µM). Whereas compounds vicanicin (4) and protolichesterinic acid (5) showed a dose-response relationship in the range of 6.25-50µM concentrations in DU-145 and LNCaP cells, activating an apoptotic process. The novel finding, in the present study, is that apoptosis induced by these compounds appears to be mediated, at least in part, via the inhibition of Hsp70 expression, that may be correlated with a modulation of redox-sensitive mechanisms. The combination of vicanicin (4) and protolichesterinic acid (5) with other anti-prostate cancer therapies could be considered a promising strategy that warrants further in vivo evaluation.

Pro-apoptotic activity of ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione in human prostate cancer cells.

With the aim of identifying novel agents with antigrowth and pro-apoptotic activity on prostate cancer cells, we assayed the effect of ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione, a semisynthetic compound, against androgen-sensitive (LNCaP) and androgen-insensitive (DU-145) human prostate cancer cells. Our results indicate that after 72h of incubation, ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione at micromolar concentrations exhibited an inhibitory effect on LNCaP and DU-145 cell growth (MTT assay), but the semisynthetic compound was the most active. In addition, our results indicate that apoptotic cell demise is induced in LNCaP and DU-145 cells. In fact, a significant increase of caspase-3 activity, not correlated to LDH release, marker of membrane breakdown, was observed in both cell lines treated with ergosterol peroxide and the semisynthetic compound. With respect to genomic DNA damage, determined by COMET and TUNEL assays, the results obtained show a significant increase in DNA fragmentation when compared with the untreated control. In conclusion, the results obtained in this study, demonstrating that ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione attenuate the growth of prostate cells, at least in part, triggering an apoptotic process, permit to confirm the use of mushrooms as origin of compounds to be used as novel therapeutic agents for prostate cancer treatment, or as models for molecules more active and selective.

Lichen metabolites prevent UV light and nitric oxide-mediated plasmid DNA damage and induce apoptosis in human melanoma cells.

In humans both UV-A and UV-B can cause gene mutations and suppress immunity, which leads to skin cancer, including melanoma. Inhibition of reactive oxygen species (ROS) and reactive nitrogen species (RNS) appears particularly promising as ROS and RNS production by both UV-A and UV-B contributes to inflammation, immunosuppression, gene mutation and carcinogenesis. We evaluated the effect of two lichen compounds, sphaerophorin (depside) and pannarin (depsidone) on pBR322 DNA cleavage induced by hydroxyl radicals (()OH), and by nitric oxide (NO), and their superoxide anion (O(2)(-)) scavenging capacity. In addition, we investigated the growth inhibitory activity of these compounds against human melanoma cells (M14 cell line). Sphaerophorin and pannarin showed a protective effect on plasmid DNA and exhibited a superoxide dismutase like effect. The data obtained in cell culture show that these lichen metabolites inhibit the growth of melanoma cells, inducing an apoptotic cell death, demonstrated by the fragmentation of genomic DNA (COMET and TUNEL Assays) and by a significant increase of caspase-3 activity, and correlated, at least in part, to the increase of ROS generation, These results confirm the promising biological properties of sphaerophorin and pannarin and encourage further investigations on their molecular mechanisms.

Demalonyl thyrsiflorin A, a semisynthetic labdane-derived diterpenoid, induces apoptosis and necrosis in human epithelial cancer cells.

In a previous study, we isolated thyrsiflorin A, a new diterpene with the scopadulane skeleton, from Calceolaria thyrsiflora (Scrophulariaceae family). Experimental evidences on the semisynthetic analogues of scopadulane diterpenes have permitted to hypothesize that a polar substituent is important for the antitumor activity of this class of compounds. Therefore, the present study was undertaken to investigate the effect of the semisynthetic compound, demalonyl thyrsiflorin A, on cell growth and death in two human epithelial cell lines, DU-145 cells (androgen-insensitive prostate cancer cells) and KB cells (oral squamous carcinoma cells). The results obtained, show that our compound, exhibited comparable degrees of antigrowth effect on cancer cells examined as judged by IC(50) values, 9.77 microM (2.73 microg/ml) and 10.86 microM (3.04 microg/ml) in DU-145 and KB cells, respectively, and support the hypothesis that also for diterpenoid compounds an available hydroxyl group is important for decreased cancer cell viability. In addition, we demonstrated an apoptotic response after treatment of DU-145 and KB cells with this semisynthetic compound at 6-12 microM concentrations, together with a necrosis process at higher doses (25-50 microM). Both apoptotic and necrotic pathway implicated in demalonyl thyrsiflorin A-treated cells are correlated with the elevation of ROS generation.

Diterpenoids from Calceolaria alba.

Chemical examination of the petrol ether (60-80) extract of the aerial parts of Calceolaria alba R. et Pav., collected in Santa Juana, VIII Region, Chile, resulted in the isolation of 3 new diterpenoids. Their structures have been elucidated by a study of their physical and spectral data; in particular using 2 NMR spectroscopy (DEPT, 1H-1H, COSY, NOESY, HMQC and HMBC).

Putrescine-1,4-dicinnamide from Pholiota spumosa (Basidiomycetes) inhibits cell growth of human prostate cancer cells.

Previously, it was isolated from the fruiting bodies of the gilled mushroom Pholiota spumosa (Basidiomycetes, Strophariaceae), putrescine-1,4-dicinnamide, a phenylpropanoid derivative conjugated with polyamine putrescine never isolated before as a natural compound. Recently, polyamine analogs that are similar in structure to the natural polyamines but that cannot mimic their functions that are essential for cellular growth and differentiation, have shown antitumor activity in several types of human cancer cells. Therefore, we have now investigated the response of DU-145 cells, a well characterized androgen-independent human prostate cancer (PCA) cell line, to this phenylpropanoid derivative. The results presented here demonstrate that putrescine-1,4-dicinnamide, as suggested for polyamine analogs synthesized artificially, inhibits the cell growth of cancer cells inducing apoptosis cell death, mediated, at least in part, by the activation of caspase cascades, that at higher doses shift to necrosis, through the increase of reactive oxygen species (ROS) generation.

Propolis protects human spermatozoa from DNA damage caused by benzo[a]pyrene and exogenous reactive oxygen species.

Many environmental, physiological and genetic factors have been implicated in defective sperm function, the most common cause of infertility. In addition, sperm preparation techniques such as centrifugation, used prior to in vitro fertilization, are associated with the generation of reactive oxygen species (ROS) and an increase in the level of DNA damage. Factors that can offer spermatozoa protection are, therefore, of great importance. This study was designed to examine in vitro the effect of a Chilean propolis ethanolic extract on human spermatozoa treated with benzo[a]pyrene and exogenous reactive oxygen species. Our experimental evidence demonstrated that the natural drug under investigation is able to protect genomic DNA by damage induced by benzo[a]pyrene, hydrogen peroxide (H2O2) and hydrogen peroxide in combination with adenosine 5'-diphosphate (ADP) and ferrous sulfate (FeSO4), determining a significant reduction of the intracellular oxidants. An increase in membrane damage, measured by monitoring the formation of thiobarbituric acid-reactive substances (TBARS) and lactic dehydrogenase (LDH) release, was observed only in sperm treated with H2O2, ADP and FeSO4. The propolis extract was shown to possess the capacity to protect sperm membrane from the deleterious action of oxidative attack, reducing TBARS formation and LDH release. In summary, our results evidence that the protective effect exhibited by this natural compound in human spermatozoa is correlated, at least in part, to the antioxidant capacity of its active components, and suggest that propolis may have a role in protection against male infertility.

Homoeostatic systems for sterols and other lipids.

Fatty acids and sterols are vital components of all eukaryotic cells. Both are used as building blocks for numerous cellular processes such as membrane biosynthesis or hormone production (sterols). Furthermore, these compounds elicit a variety of effects intracellularly as they can act as signalling molecules and regulate gene expression. The metabolism of fatty acids and sterols represents a very intricate network of pathways that are regulated in a precise manner in order to maintain lipid homoeostasis within a cell. Using the budding yeast Saccharomyces cerevisiae as a model system, we touch upon some of the aspects of achieving and maintaining this lipid homoeostasis.

Chilean propolis: antioxidant activity and antiproliferative action in human tumor cell lines.

Propolis, a natural product derived from plant resins collected by honeybees, has been used for thousands of years in traditional medicine all over the world. The composition of the propolis depends upon the vegetation of the area from where it was collected and on the bee species. In this study, we investigated the antioxidant activity of a propolis sample, provided by NATURANDES-CHILE, collected in a temperate region of central Chile. In addition, this natural compound was tested for its antiproliferative capacity on KB (human mouth epidermoid carcinoma cells), Caco-2 (colon adenocarcinoma cells) and DU-145 (androgen-insensitive prostate cancer cells) human tumor cell lines. Results showed that this Chilean propolis sample exhibits interesting biological properties, correlated with its chemical composition and expressed by its capacity to scavenge free radicals and to inhibit tumor cell growth.

Field and laboratory arsenic speciation methods and their application to natural-water analysis.

The toxic and carcinogenic properties of inorganic and organic arsenic species make their determination in natural water vitally important. Determination of individual inorganic and organic arsenic species is critical because the toxicology, mobility, and adsorptivity vary substantially. Several methods for the speciation of arsenic in groundwater, surface-water, and acid mine drainage sample matrices using field and laboratory techniques are presented. The methods provide quantitative determination of arsenite [As(III)], arsenate [As(V)], monomethylarsonate (MMA), dimethylarsinate (DMA), and roxarsone in 2-8 min at detection limits of less than 1 microg arsenic per liter (microg As L(-1)). All the methods use anion exchange chromatography to separate the arsenic species and inductively coupled plasma-mass spectrometry as an arsenic-specific detector. Different methods were needed because some sample matrices did not have all arsenic species present or were incompatible with particular high-performance liquid chromatography (HPLC) mobile phases. The bias and variability of the methods were evaluated using total arsenic, As(III), As(V), DMA, and MMA results from more than 100 surface-water, groundwater, and acid mine drainage samples, and reference materials. Concentrations in test samples were as much as 13,000 microg As L(-1) for As(III) and 3700 microg As L(-1) for As(V). Methylated arsenic species were less than 100 microg As L(-1) and were found only in certain surface-water samples, and roxarsone was not detected in any of the water samples tested. The distribution of inorganic arsenic species in the test samples ranged from 0% to 90% As(III). Laboratory-speciation method variability for As(III), As(V), MMA, and DMA in reagent water at 0.5 microg As L(-1) was 8-13% (n=7). Field-speciation method variability for As(III) and As(V) at 1 microg As L(-1) in reagent water was 3-4% (n=3).

Cytotoxic activity of the root extract from Myoschilos oblongum.

The crude methanolic root extract of Myoschilos oblongum exhibited a significant cytotoxic activity against PZ-HPV-7 human prostate cells. Furthermore, two esters of docosanol were isolated from the CH(2)Cl(2) extract.

Environmental fate of roxarsone in poultry litter. I. Degradation of roxarsone during composting.

Roxarsone, 3-nitro-4-hydroxyphenylarsonic acid, is an organoarsenic compound that is used extensively in the feed of broiler poultry to control coccidial intestinal parasites, improve feed efficiency, and promote rapid growth. Nearly all the roxarsone in the feed is excreted unchanged in the manure. Poultry litter composed of the manure and bedding material has a high nutrient content and is used routinely as a fertilizer on cropland and pasture. Investigations were conducted to determine the fate of poultry-litter roxarsone in the environment Experiments indicated that roxarsone was stable in fresh dried litter; the primary arsenic species extracted with water from dried litter was roxarsone. However, when water was added to litter at about 50 wt % and the mixture was allowed to compost at 40 degrees C, the speciation of arsenic shifted from roxarsone to primarily arsenate in about 30 days. Increasing the amount of water increased the rate of degradation. Experiments also suggested that the degradation process most likely was biotic in nature. The rate of degradation was directly proportional to the incubation temperature; heat sterilization eliminated the degradation. Biotic degradation also was supported by results from enterobacteriaceae growth media that were inoculated with litter slurry to enhance the biotic processes and to reduce the concomitant abiotic effects from the complex litter solution. Samples collected from a variety of litter windrows in Arkansas, Oklahoma, and Maryland also showed that roxarsone originally present had been converted to arsenate.

Environmental fate of roxarsone in poultry litter. Part II. Mobility of arsenic in soils amended with poultry litter.

Poultry litter often contains arsenic as a result of organo-arsenical feed additives. When the poultry litter is applied to agricultural fields, the arsenic is released to the environment and may result in increased arsenic in surface and groundwater and increased uptake by plants. The release of arsenic from poultry litter, litter-amended soils, and soils without litter amendment was examined by extraction with water and strong acids (HCI and HNO3). The extracts were analyzed for As, C, P, Cu, Zn, and Fe. Copper, zinc, and iron are also poultry feed additives. Soils with a known history of litter application and controlled application rate of arsenic-containing poultry litter were obtained from the University of Maryland Agricultural Experiment Station. Soils from fields with long-term application of poultry litter were obtained from a tilled field on the Delmarva Peninsula (MD) and an untilled Oklahoma pasture. Samples from an adjacent forest or nearby pasture that had no history of litter application were used as controls. Depth profiles were sampled for the Oklahoma pasture soils. Analysis of the poultry litter showed that 75% of the arsenic was readily soluble in water. Extraction of soils shows that weakly bound arsenic mobilized by water correlates positively with C, P, Cu, and Zn in amended fields and appears to come primarily from the litter. Strongly bound arsenic correlates positively with Fe in amended fields and suggests sorption or coprecipitation of As and Fe in the soil column.

Photodegradation of roxarsone in poultry litter leachates.

Arsenic compounds have been used extensively in agriculture in the US for applications ranging from cotton herbicides to animal feed supplements. Roxarsone (3-nitro-4-hydroxyphenylarsonic acid), in particular, is used widely in poultry production to control coccidial intestinal parasites. It is excreted unchanged in the manure and introduced into the environment when litter is applied to farmland as fertilizer. Although the toxicity of roxarsone is less than that of inorganic arsenic, roxarsone can degrade, biotically and abiotically, to produce more toxic inorganic forms of arsenic, such as arsenite and arsenate. Experiments were conducted on aqueous litter leachates to test the stability of roxarsone under different conditions. Laboratory experiments have shown that arsenite can be cleaved photolytically from the roxarsone moiety at pH 4-8 and that the degradation rate increases with increasing pH. Furthermore, the rate of photodegradation increases with nitrate and natural organic matter concentration, reactants that are commonly found in poultry-litter-water leachates. Additional photochemical reactions rapidly oxidize the cleaved arsenite to arsenate. The formation of arsenate is not entirely undesirable, because it is less mobile in soil systems and less toxic than arsenite. A possible mechanism for the degradation of roxarsone in poultry litter leachates is proposed. The results suggest that poultry litter storage and field application practices could affect the degradation of roxarsone and subsequent mobilization of inorganic arsenic species.

Mass spectrometric identification of an azobenzene derivative produced by smectite-catalyzed conversion of 3-amino-4-hydroxyphenylarsonic acid.

The compound 3-amino-4-hydroxyphenylarsonic acid (3-amino-HPAA) reacts with smectite to form a soluble azobenzene arsonic acid compound. This reaction is of particular interest because it provides a possible mechanism for the formation of a new type of arsenic compound in natural water systems. 3-Amino-HPAA is a degradation product excreted by chickens that are fed rations amended with roxarsone. Roxarsone is used to control coccidial intestinal parasites in most of the broiler chickens grown in the United States. The structure of the azobenzene arsonic acid compound was first inferred from negative-ion and positive-ion low-resolution mass-spectrometric analyses of the supernatant of the smectite suspension. Elemental composition of the parent ion determined by high-resolution positive-ion mass spectrometric measurements was consistent with the proposed structure of the azobenzene arsonic acid compound.

Presence of organoarsenicals used in cotton production in agricultural water and soil of the southern United States.

Arsenicals have been used extensively in agriculture in the United States as insecticides and herbicides. Mono- and disodium methylarsonate and dimethylarsinic acid are organoarsenicals used to control weeds in cotton fields and as defoliation agents applied prior to cotton harvesting. Because the toxicity of most organoarsenicals is less than that of inorganic arsenic species, the introduction of these compounds into the environment might seem benign. However, biotic and abiotic degradation reactions can produce more problematic inorganic forms of arsenic, such as arsenite [As(III)] and arsenate [As(V)]. This study investigates the occurrences of these compounds in samples of soil and associated surface and groundwaters. Preliminary results show that surface water samples from cotton-producing areas have elevated concentrations of methylarsenic species (>10 microg of As/L) compared to background areas (<1 microg of As/L). Species transformations also occur between surface waters and adjacent soils and groundwaters, which also contain elevated arsenic. The data indicate that point sources of arsenic related to agriculture might be responsible for increased arsenic concentrations in local irrigation wells, although the elevated concentrations did not exceed the new (2002) arsenic maximum contaminant level of 10 microg/L in any of the wells sampled thus far.

Preserving the distribution of inorganic arsenic species in groundwater and acid mine drainage samples.

The distribution of inorganic arsenic species must be preserved in the field to eliminate changes caused by metal oxyhydroxide precipitation, photochemical oxidation, and redox reactions. Arsenic species sorb to iron and manganese oxyhydroxide precipitates, and arsenite can be oxidized to arsenate by photolytically produced free radicals in many sample matrices. Several preservatives were evaluated to minimize metal oxyhydroxide precipitation, such as inorganic acids and ethylenediaminetetraacetic acid (EDTA). EDTA was found to work best for all sample matrices tested. Storing samples in opaque polyethylene bottles eliminated the effects of photochemical reactions. The preservation technique was tested on 71 groundwater and six acid mine drainage samples. Concentrations in groundwater samples reached 720 microg-As/L for arsenite and 1080 microg-As/L for arsenate, and acid mine drainage samples reached 13 000 microg-As/L for arsenite and 3700 microg-As/L for arsenate. The arsenic species distribution in the samples ranged from 0 to 90% arsenite. The stability of the preservation technique was established by comparing laboratory arsenic speciation results for samples preserved in the field to results for subsamples speciated onsite. Statistical analyses indicated that the difference between arsenite and arsenate concentrations for samples preserved with EDTA in opaque bottles and field speciation results were analytically insignificant. The percentage change in arsenite:arsenate ratios for a preserved acid mine drainage sample and groundwater sample during a 3-month period was -5 and +3%, respectively.