613 research outputs found

    Nondestructive biomarkers in ecotoxicology.

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    The aim of this article is to attempt a concise review of the state of the art of the nondestructive biomarkers approach in vertebrates, establishing a consensus on the most useful and sensitive nondestructive biomarker techniques, and proposing research priorities for the development and validation of this promising methodology. The following topics are discussed: the advantages of the use of nondestructive strategies in biomonitoring programs and the research fields in which nondestructive biomarkers can be applied; the biological materials suitable for nondestructive biomarkers and residue analysis in vertebrates; which biomarkers lend themselves to noninvasive techniques; and the validation and implementation strategy of the nondestructive biomarker approach. Examples of applications of this methodology in the hazard assessment of endangered species are also presented

    The short future of public broadcasting: Replacing digital terrestrial television with internet protocol?

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    According to recent European estimates, the life expectancy of broadcasting as a free-to-air television platform is not more than 15 years. BBC, Yle and the UK regulator Ofcom have reached this conclusion in their reports about the future of news, media distribution and digital terrestrial television (DTT). Although broadcasting is seen as necessary until 2030, all three assume that DTT can – under certain conditions – be replaced with delivery using internet protocol (IP). However, it seems that the idea of IPTV taking over DTT is just a sophisticated version of “black box fallacy”, driven by the expected growth of the new media ecosystem. The problems in replacing a socio-technological system have largely been neglected

    The X-ray spectra of the flaring and quiescent states of AT Microscopii observed by XMM-Newton

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    The X-ray spectrum of the late-type M-dwarf binary AT Mic (dM4.5e+dM4.5e) is observed in the wavelength range 1 - 40 Angstrom by means of rgs and epic-mos on board XMM-Newton. During the exposure a flare occured. We have performed a 3-temperature fit and a DEM-modeling to the flaring and quiescent part of the spectrum. We report the coronal temperature distribution, emission measures, and abundances of the flaring and quiescent state of this bright X-ray source. The temperature range stretches from about 1 to 60 MK. The total volume emission measure in this temperature interval is ~12.2*10^51 cm^-3 for the quiescent state and ~19.5*10^51 cm^-3 for the flare state. This difference is due to the contribution of the hot temperature component. The high-resolution spectrum of AT Mic, obtained by rgs, is dominated by the H- and He-like transitions of C, N, O, and Ne and by Fe XVII lines, produced by the plasma with temperatures from 1 to 10 MK. The epic-mos spectrum below 10 Angstrom shows H- and He-like Ne, Si and the iron K-shell transitions. They are produced by the hot component (30 MK). The iron K-shell is more prominent in the flare state. The abundance pattern in the quiescent state of AT Mic shows the depletion of low-FIP elements relative to high-FIP elements, indicating the presence of an I(nverse)FIP effect in this active star. In the flare state, however, some flattening of this IFIP effect is present.Comment: 7 pages, 11 figures ordered as: 1, 2ab, 3, 4abc, 5ab, 6a

    Risk factors of cervical intraepithelial lesion in Douala-Cameroon: Implications of Herpes Simplex Virus Type 2, Chlamydia Trachomatis and Treponema Pallidum

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    Infection with high risk oncogenic human papillomavirus (HPV) such as HPVs 16 and 18 is the main cause of cervical cancer. The objective of this study was to determine the impact of Chlamydia trachomatis, Herpes simplex virus 2 (HSV 2), Treponema pallidum and some sexual behaviour on malignant progression of cervical lesion in Douala, Cameroon. From July 2009 to January 2010, we performed routine cervical smears to 163 consenting women, who completed a questionnaire on risk factors of cervical cancer. Blood samples were obtained for each of these women and used for the detection of antibodies against Chlamydia trachomatis, HSV 2 and Treponema pallidum. Results obtained showed that 26/163 (17 LSIL and 9 HSIL) of women had abnormal cytology, 75.5% (123/163) had HSV 2 infection, 19% (31/163) infected by Chlamydia trachomatis and 4.3% (7/163) infected by Treponema pallidum. Among the LSIL-positive women 35.3% (6/17) and 94.1% (16/17) were infected with Chlamydia trachomatis and HSV 2 respectively. Among those with HSIL cytology, 22.2% (2/9), 66.7% (6/9) and 11.1% (1/9) respectively had Chlamydia trachomatis, HSV 2 and Treponema pallidum. High parity and pregnancy rate was observed among women with positive cytology. Our finding shown high rate of cervical abnormalities among women infected with HSV 2; and among those with a higher number of parities and pregnancies. These results suggest that further investigations should be made in Cameroon to access real burden of these risk factors in the progression and persistence of cervical lesion.Key words:risk factors, cervical cancer, HSV 2, Chlamydia trachomatis, sexually transmitted infections.doi: 10.4314/ajcem.v12i3.

    Effects of copper on larvae of the marbled crab Pachygrapsus marmoratus (Decapoda, Grapsidae): toxicity test and biochemical marker responses

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    The importance of trace elements in ecotoxicological investigations is a well-known issue when monitoring polluted areas such as commercial harbors. Copper represents one of the most common metal contaminants, often detected in these areas as it is widely employed in various fields and has many sources of inflow in the marine environment. Pachygrapsus marmoratus is a widespread intertidal crab species that has been extensively studied in ecology, ethology and population genetics. Ecotoxicological studies have also been performed, exclusively on the adult stage. In the present study we investigated the mortality and biochemical (oxidative stress and neurotoxicity) responses of P. marmoratus larvae exposure to environmental relevant concentration of copper. Results showed dose-dependent responses in terms of larval mortality, with a calculated LC50 value of 0.5 mg/L of Cu2+. The LC50 concentration was used as the starting point for subsequent biochemical response evaluation. Results also demonstrated dose-dependent activation of antioxidant systems assuming a compensatory antioxidant activity to prevent higher cellular damage when larvae were exposed to the highest concentrations of copper. Moreover, a significant enhancement of neurotransmitter activities was observed, assuming a possible direct interaction of copper with the enzymes or an increase of free copper ion aliquot into the cells.publishe

    Pirfenidone in idiopathic pulmonary fibrosis: real-life experience in the referral centre of Siena

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    Background: Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial pneumonia and has a median survival after diagnosis of 2–5 years. Pirfenidone is the first approved antifibrotic drug for the treatment of IPF. Here we report the functional progress, side effects and survival data of a population of patients with IPF, diagnosed at our centre and treated with pirfenidone. Methods: We enrolled 91 patients with IPF (71 males) treated with pirfenidone. Clinical, survival and functional details were collected retrospectively at start of therapy and after 12, 24, 36 and 48 months of treatment. Lung function tests at least 12 months before starting therapy were available for 40 patients and were entered in the database, as well as side effects. Results: During the observation period (922 ± 529 days), 27 patients died, 5 patients underwent lung transplant and 10 patients interrupted therapy due to adverse events or IPF progression. The median survival was 1606 days. There was a significant reduction in disease progression rate, as measured by trend of forced vital capacity, after 1 year of therapy with respect to before treatment (p = 0.0085). Forced vital capacity reduction rate was progressively higher in the subsequent years of treatment. Treatment-related side effects were reported in 25 patients and were predominantly mild. Overall, four patients discontinued therapy due to severe photosensitivity. Conclusions: Our findings confirm the efficacy of pirfenidone in reducing functional progression of IPF and its excellent safety profile in a real-life setting. This study, designed on a long-term follow up, contributes to the growing evidence on safety, tolerability and efficacy of pirfenidone in IPF. The reviews of this paper are available via the supplemental material section
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