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In Vitro Genotoxicity of Settat Town Landfill Leachate, Morocco

In Vitro Genotoxicity of Settat Town Landfill Leachate, Morocco

With the increasing use of landfill sites, leachates produced by uncontrolled waste disposal have became a serious threat for the aquatic environment. The aim of this study was to evaluate the genotoxicity of leachate and of well water sampled close to the town of Settat in Morocco using the micronucleus test and proliferation kinetics of human peripheral blood lymphocytes in vitro. We also analysed a number of physical and chemical parameters, including pH, % O2, chemical oxygen demand (COD), HCO3 -, Ca2+, Mg2+, Cl-, and conductivity.

The analysis showed much higher levels of nearly all parameters than the Moroccan standard. Increased micronucleus frequencies were also found for both leachate and well water. Preliminary results indicate that both types of water are genotoxic and pose environmental and human health risk.

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Behavior of various Nigerian quartz samples to repeated irradiation and heating

Abstract

In the present work the sensitization of the entire glow-curve is studied in 6 different quartz samples of Nigerian origin. The investigation was applied to the un-fired “as is” samples as well as to samples fired at 900°C for 1 hour following cooling to room temperature. The results showed that in the case of “as is” glow-curve is sensitized as a whole. There is an abrupt transition from the “natural” sensitivity without any previous heating and the artificial sensitivity induced after the first heating. The sensitization is growing up strongly to the 10th heating but to a lower rate. The sensitization factor of the TL glow-peak at “110°C” was found to be linearly correlated to the higher temperature TL peaks. In the case of annealed samples there is an initial increase between the sensitivity immediately after the end of annealing and after the first heating. As the number of heating is increased up to the 10th heating the sensitization is stabilized at a constant value. The results are discussed in the frame-work of existing models and implications of the sensitization effect in various applications, while some explanations are attempted.

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Dose Rate Effect of Pulsed Electron Beam on Micronucleus Frequency in Human Peripheral Blood Lymphocytes

Dose Rate Effect of Pulsed Electron Beam on Micronucleus Frequency in Human Peripheral Blood Lymphocytes

The micronucleus assay in human peripheral blood lymphocytes is a sensitive indicator of radiation damage and could serve as a biological dosimeter in evaluating suspected overexposure to ionising radiation. Micronucleus (MN) frequency as a measure of chromosomal damage has also extensively been employed to quantify the effects of radiation dose rate on biological systems. Here we studied the effects of 8 MeV pulsed electron beam emitted by Microtron electron accelerator on MN induction at dose rates between 35 Gy min-1 and 352.5 Gy min-1. These dose rates were achieved by varying the pulse repetition rate (PRR). Fricke dosimeter was employed to measure the absorbed dose at different PRR and to ensure uniform dose distribution of the electron beam. To study the dose rate effect, blood samples were irradiated to an absorbed dose of (4.7±0.2) Gy at different rates and cytogenetic damage was quantified using the micronucleus assay. The obtained MN frequency showed no dose rate dependence within the studied dose rate range. Our earlier dose effect study using 8 MeV electrons revealed that the response of MN was linear-quadratic. Therefore, in the event of an accident, dose estimation can be made using linear-quadratic dose response parameters, without adding dose rate as a correction factor.

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Copd and occupation: a retrospective cohort study of industrial workers

The aim of this paper was to ascertain chronic obstructive pulmonary disease (COPD) prevalence among industrial workers in the Russian Federation and determine relative contribution of smoking and occupational factors to COPD. We recruited 1,375 workers aged 30 or over. Six hundred and twenty-four of them were occupationally exposed to vapours, gases, dust, and fumes (VGDF). Physical examination and baseline spirometry were performed for all the participants of the study. Those with airfl ow limitation of FEV1/FVC<0.70 were considered having COPD and those with presence of cough and sputum production for at least three months in each of two consecutive years were considered having chronic bronchitis (CB), with no overlapping between these 2 groups. Data on occupational history and VGDF levels in the working area were collected from all participants. In total, 105 cases of COPD and 170 cases of CB were diagnosed in the cohort of examined workers. Occupational exposure to VGDF was twice as often present among COPD patients than among both patients with CB and the control group of healthy workers (p<0.05). More than 40 % of COPD patients were occupationally exposed to VGDF above the value of 3.0 of the occupational exposure limit (OEL) and more than 20 % to 6.0 OEL and higher. Overall odds ratio for COPD development due to occupational VGDF exposure was 5.9 (95 % CI=3.6 to 9.8, p=0.0001). Both smoking and VGDF seem to be important for the development of COPD. Analysis of the combined effect of tobacco smoking and occupational noxious particles and gases on COPD development has shown the following order of risk factors based on the strength of their infl uence: VGDF levels, smoking index, age, and heating microclimate. There is a statistically signifi cant level of relationship and “dose-effect” dependence between occupational exposures to VGDF and the development of COPD. The effect of VGDF composition on the probability of COPD development was not found in the study. Results of this study were used to substantiate the inclusion of COPD into the National List of Occupational Diseases of the Russian Federation.

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External beam radiotherapy for palliation of painful bone metastases: pooled data bioeffect dose response analysis of dose fractionation

-537. Orton CG. Time dose factors in brachytherapy. Brit J Radiol. 1974; 47: 603-607. Barendson GW. Dose fractionation, dose rate and isoeffect relationship for normal tissue responses. Int J Rad Oncol Biol Phys. 1982; 8: 1981-1997. Dale RG. The application of the linear quadratic dose effect equation to fractionated and protracted radiotherapy. Brit J Radiol. 1985; 58: 515-528. Dale RG. The application of the linear quadratic model to fractionated radiotherapy when there is incomplete normal

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Synergistic interaction of levetiracetam with gabapentin in the mouse 6 Hz psychomotor seizure model – a type II isobolographic analysis

synergism and dose-effect data analysis. Chapman & Hall/CRC, Boca Raton. 17. Wojda E. et al.: Isobolographic characterization of interactions of levetiracetam with the various antiepileptic drugs in the mouse 6 Hz psychomotor seizure model. Epilepsy Res., 86, 163, 2009.

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Electrically Active Defects In Solar Cells Based On Amorphous Silicon/Crystalline Silicon Heterojunction After Irradiation By Heavy Xe Ions

Solar Cells, Physics and Technology of Amorphous-Crystalline Heterostructure Silicon Solar Cell, Springer, Berlin, Heidelberg, 2012, pp. 13–43. [6] HARMATHA, L.—MIKOLÁŠEK, M.— NEMEC, M.—JANÍČEK, F.—HRUBČÍN, L.—SKURATOV, V. A.: Electrical Properties of Solar Cells with a Heterojunction of Amorphous and Crystalline Silicon Irradiated by Heavy Xenon Ions, J. Electr. Engineering 65 No. 7s (2014), 30–33. [7] FANG, R.—VELO, Y. G.—CHEN, W.—HOLBERT, K. E.— KOZICKI, M. N.—BARNABY, H.—YU, S. : Total Ionizing Dose Effect of γ-ray radiation on the switching

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The Acute Effect of Resistance Exercise with Blood Flow Restriction with Hemodynamic Variables on Hypertensive Subjects

; 24: 1277-1284 Suga T, Okita K, Morita N, Yokota T, Hira-Bayashi K, Horiuchi M, Takada S, Omokawa M, Kinugawa S, Tsutsui H. Dose effect on intramuscular metabolic stress during low-intensity resistance exercise with blood flow restriction. J Appl Physiol, 2010; 108: 1563-1567 World Health Organization (WHO)/ International Society of Hypertension (ISH) statement on management of hypertension. J Hypertension, 1999; 17: 151-183

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Antinociceptive Effect of Clomipramine Through Interaction with Serotonin 5-Нт2 And 5-Нт3 Receptor Subtypes

Abstract

INTRODUCTION: Tricyclic antidepressants are used in the treatment of various pain syndromes. The antidepressant clomipramine inhibits predominantly the reuptake of serotonin in the central nervous system. The mechanism of its analgesic effect is not fully understood.

The AIM of the present study was to find experimentally any dose-effect dependence in the analgesic effect of clomipramine and the involvement of the 5-НТ2 and 5-НТ3 receptors in the mechanism of this effect. Material and methods: Fifty male Wistar rats were used in the study allocated to five groups (10 animals each): a saline treated control group, one positive control group treated with metamizole and three experimental groups treated with intraperitoneally administered clomipramine in doses of 5, 10 and 20 mg/kg bw, respectively. To study the role of 5-НТ2 and 5-НТ3 receptors in this effect we used another five groups (10 animals each): control, positive control and three experimental groups treated with clomipramine only, clomipramine and granisetrone and clomipramine and cyproheptadine, respectively. Three nociceptive tests were used: the hot plate test, analgesimeter and the acetic acid-induced writhing test. To gauge the antinociceptive action we used the increased latency in the hot plate test expressed as maximum possible effect % (%MPE), the increase in paw pressure to withdraw the hind paw in analgesimeter and decrease in the number of spinal cord writhes in the acetic acid test.

RESULTS: Clomipramine in a dose of 20 mg/kg bw significantly increased the %MPE in hot plate test and the pressure to withdraw the hind paw in the analgesimeter when compared with the control. In the acetic acid test clomipramine decreased non-significantly the number of writhes compared with the controls. Granisetrone reduced non-significantly the antinociceptive effect of clomipramine in all tests. Cyproheptadine potentiated the analgesic effect of clomipramine in acetic acid test and decreased it significantly in the hot plate test. In analgesimeter cyproheptadine decreased significantly the paw pressure to withdraw the tested hind paw at 1 hour and non-significantly at 2 hours.

CONCLUSION: Clomipramine in the dose of 20 mg/kg bw has a pronounced antinociceptive affect towards thermal and mechanical pain stimulation. The 5-HT2 and 5-HT3 receptor subtypes are very likely involved in the mechanism of this effect.

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Influence of in Situ Temperature on the Sensitization of Quartz: A Simulation Study

. Radiation Measure-ments 33: 47-57, DOI 10.1016/S1350-4487(00)00133-5. Chen R, 1969. Glow curves with general order kinetics. Journal of The Electrochemical Society 116: 1254-1257, DOI 10.1149/1.2412291. Kitis G, Pagonis V, Chen R and Polymeris GS, 2006. A comprehensive comparative study of the pre-dose effect for three quartz crystals of different origins. Radiation Protection Dosimetry 119: 438-441, DOI 10.1093/rpd/nci548. Koul DK and Chougaonkar MP, 2007. Pre-dose phenomenon in the OSL signal of quartz. Radiation

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