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EN
The impact of some organotin compounds (10-200 mg dm^3) on the planktonic cyanobacterium Synechocystis aquatilis was studied. The following order of toxicity of organotins tested to the cyanobacterium culture was found: DBTCl TPTAclTBTCl? TPTCl TMTCl. Chlorophyll a content in the culture seemed to be more susceptible to organotins than cyanobacterial growth. The inhibition of both parameters increased significantly with the increase of compound doses, time of exposure and decrease of initial culture density. After 96 h exposure, the chlorophyll a content in the cyanobacte-rium cultures of the initial density 56 mg dry wt dm^3 was reduced for 200 mg dm^3 of DBTCl, TBTCl and TPTCl by 70%, 50% and 20% respectively, while in the cultures of the lowest initial density (10 mg dry wt dm-3) by 90%, 75% and 50%, as compared to the organotin free controls.
PL
Stosowane dotychczas chemiczne i biologiczne testy teksyczności opartą na zjawisku bioluminescencji oraz aparaturę do jej pomiaru produkowaną przez firmę Merck.
EN
The hitherto used chemical and biological methods of water toxicity testing shaw a number of shortcomings. The paper describes a new method for toxicity testing based on the phenomenon of biolumines-cence and the devices for measurement of toxicity produced by the firm Merck.
EN
This work is the third part of the articles published on the effects of the shape and position of the combustion chamber in piston compression diesel engines on the toxicity of exhaust gases. In two previous articles presented at the KONES 2015 conference, the impact of position of the combustion chamber in relation to position of the injector, and the influence of the shape of the chamber (diameter, depth, lip on the CO, HC and NOx emissions was analysed. In the current article, the shape of the “central body” in a combustion chamber is analysed. “Central body” is the protrusion located in the central part of a toroidal combustion chamber. Subsequent modifications to the basic combustion chamber consisted of reducing the size of this protrusion. The study involved four versions of combustion chambers. Modifications caused a slight decrease in the compression ratio, which could have an impact on the unambiguousness of the results, as the effect of changes in shape of the “central body”. However, to maintain a constant compression ratio would require a change in diameter or depth of the chamber cavity, which would obscure the obtained results with even greater impact. Emission tests in discussed study were performed according to ECE-R4. During the tests, the completion of the engine and the engine settings were not changed.
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Content available Toxicity of bisphenol a on humans: a review
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EN
Bisphenol A (BPA) is a plastic ingredient produced in large quantities for use primarily in the production of polycarbonate plastics and epoxy resins. The present review focused on different mechanisms of BPA on human health in enzymatic, androgenic, neurological, liver and reproductive systems. The review explained the influence of BPA on different stages of human life likely in foetal stage, children and adults stages. The review also concentrated on how to handle BPA, treatment, preventive measures against BPA exposure.
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Content available GTD-350 engine powered by LPG : research work
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EN
The paper presents results of comparative tests of exhaust gases toxicity of GTD-350 turboshaft engine powered by Liquefied Petroleum Gas (LPG) and conventional JET-A1 fuel. Structure of GTD-350 engine’s test bed was discussed. Because of explosion danger of LPG vapour the test stand was arranged in the open air. Paper comprises specification of LPG supply system, gas injector’s construction and visualization of LPG injection. The supply system was based on the newly constructed pressurized injectors. Required LPG operating pressure was obtained by pressurizing LPG tank using nitrogen and LPG-flow was controlled using needle valve. A series of photographs presents shape of fuel streams for new injector supplied by JET-A1 and LPG. Photos of flame torches for multi-hole and conical type injectors fuelled by LPG are inserted as well. A comparative study of carbon monoxide, nitrogen oxides, hydrocarbons and carbon dioxide as well as oxygen concentration for GTD-350 equipped with new injectors fuelled by LPG and standard supplied by Jet-A1 was carried out. The study comprised turbocharger speed range between 40 and 80% of NTS. The exhaust gas temperature comparison for above-mentioned configuration is presented as well. All data shown in presented figures are mean of 6 measurements. All completed tests were carried out for standard GTD-350 engine combustion chamber.
OncoReview
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2016
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tom 6
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nr 3
A143-148
EN
Introduction: Everolimus is a selective mTOR inhibitor which received approval for treatment of advanced renal cell carcinoma (mRCC) after progression on or after treatment with VEGF-targeted therapy. The aim of this study was to evaluate the efficiency and toxicity profile of everolimus in second line therapy of mRCC. The authors also assessed the impact of clinicopathological factors on the effectiveness of everolimus. Methods: The retrospective analysis was conducted on the medical records of 33 mRCC patients who were treated with everolimus in second line therapy after progression on interferon or tyrosine kinase inhibitors (sunitinib or pazopanib) during the years 2010–2016. Results: Median time of treatment with everolimus was 4 months (range from 1 to 58 months). Median progression free survival was 4 months and overall survival (OS) was 11 months. The best response (PR + CR + SD) was reported in 57% of patients. Toxicity in grade 3–4 was reported in 9 (27%) of patients. Clinicopathological factors associated with progression during everolimus therapy were: smoking and alcohol abuse (p = 0.029), higher Furman grade (p = 0.166), tumor necrosis (p = 0.383), fat tissue infiltration (p = 0.040), lymph node (p = 0.193) and adrenal metastases (p = 0.067). Factors which increase the risk of everolimus toxicity were worse performance status (p = 0.333) and more advanced disease at the beginning (lymph nodes metastases, p = 0.05) and higher Furman grade (p = 0.04). Conclusions: Cigarettes use and/or alcohol abuse, adrenal metastases, fat tissue had significantly negative influence on survival. Grade 3–4 toxicity were reported more frequently in patients with worse performance status and more advanced disease at the time of diagnosis.
EN
Cytostatic drugs have become one of the greatest environmental hazards. They exhibit toxic, carcinogenic, mutagenic and teratogenic effects on flora and fauna, including people. They are poorly eliminated in conventional wastewater treatment plants and their mixtures could possess higher ecotoxicity than individual drugs. Fungi are organisms with enormous potential for biodegradation of a variety of toxic chemical pollutants. The aim of this work was to estimate tolerance of five fungal strains to selected anticancer drugs, which will be useful to determine the potential for their possible use in cytostatics removal and may be significant in the context of wastewater treatment application. Test was conducted on Fomes fomentarius (CB13), Hypholoma fasciculare (CB15), Phyllotopsis nidulans (CB14), Pleurotus ostreatus (BWPH) and Trametes versicolor (CB8) and the chosen drugs were bleomycin and vincristine. Their ability to grow in the presence of selected cytostatics was evaluated in cultures conducted on two solid media which differed in the richness of nutrient compounds. Fungal strains tolerance was expressed as a half maximal effective concentration. Results showed that fungi display better tolerance to high cytostatics’ concentrations in the medium rich in carbon source. Regardless of the medium used, the differences in growth ability were lower for bleomycin (the tolerance was higher). The greatest tolerance for bleomycin was shown by Pleurotus ostreatus. Results suggest that more efficient elimination of bleomycin would be possible to obtain, strain BWPH seems to be the best fungal candidate for this drug degradation assay and, probably, in wastewater treatment application tests in a longer perspective.
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Content available remote Concentrations of heavy metals (Mn, Co, Ni, Cr, Ag, Pb) in coffee
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EN
Aim: Technologies involved in roasting coffee beans, as well as the methods used to prepare infusions, vary according to culture, and contribute to differences in the concentration of elements in the drink. Materials and Methods: Concentrations of six elements: manganese (Mn), cobalt (Co), nickel (Ni), chrome (Cr), silver (Ag) and lead (Pb) were investigated in coffee infusions from eleven samples of coffee, roasted and purchased in four countries: Bosnia and Herzegovina, Brazil, Lebanon and Poland. Metal concentrations were determined using an induction coupled plasma technique in combination with mass spectrometry (ICP-MS, Perkin Elmer) which measures total metal (ionic and non-ionic) content. Results: Metal intake estimated for individual countries (in the respective order; mean consumption per person per year) was as follows: Mn: 26.8-33.1, 28.3-29.5, 29.7, 12.6-18.9 mg; Co: 0.33-0.48, 0.42-0.35, 0.32, 0.12-0.17 mg; Ni: 3.83-5.68, 4.85-5.51, 4.04, 2.06-2.24 mg; Cr: 0.17-0.41, 0.21-0.47, 0.17, 0.09-0.28 mg; Ag: 0.16-1.13, 0.26-0.70, 0.61, 0.33-1.54 mg, Pb: 4.76-7.56, 3.59-5.13, 3.33, 1.48-2.43 mg. Conclusions: This finding gives new data for Mn, Co, Ni, Cr, and Ag intake from coffee , and suggests that the amounts are negligible. However, the data for Pb consumption in heavy drinkers, for example in Bosnia and Herzegovina, indicate that Pb intake from coffee may contribute to the disease burden. The high lead level in some coffees suggests the need for a more precise control of coffee contamination.
EN
An important issue in construction of combustion chamber in compression-ignition engines is proper selection of its shape and size. Both features are dependent on several factors such as fuel injector location and angle, spray atomizer selection (amount of holes, their diameter and angular position), location of inlet valve and air turbulence. By doing research on prototype engine T370, an analysis of influence of combustion chamber size and its modifications going towards lip construction on flue gas toxicity was done. The diameter and depth of combustion chamber was being changed while maintaining the same compression ratio. After that, a modification of tested combustion chambers was made by creating so called “lip”, which aim was to create a swirl of injected fuel in the vertical plane. To visualize the changes in swirl, a numerical analysis of fuel injection into combustion chamber was made. In discussed study, emission tests were performed according to ECE-R49. During the research six combustion chambers with diameters 60, 63 and 66 mm (and their modification) were investigated. Tests were performed for several types of injectors and different injection timing. However, for analysis of combustion chamber size the results are presented for the same injectors but with optimized injection timing.
EN
The aim of the research was to study the impact of "Oława" smelter on surroundings. For this purpose, water, soil and sediments were collected in the vicinity of smelter and subjected to selected ecotoxicological tests. The authors used Spirodela polyrhiza duckweed and Brachinious calyciflorus rotifer for the assessment of the water from Odra River, and Heterocypris inconqruens ostracod for the sediment studies. Triticum sativum and Avena sativa monocotyledons as well as Sinapis alba and Lepidium sativum dicotyledonous plants were used to perform the soil toxicity tests. The obtained results proved slight sediment toxicity, but no toxicity of water was observed. The inhibition of root growth of tested plants was observed suggesting the impact of toxicity on soil. The studies proved that only the area in the nearest vicinity of the "Oława" smelter is still contaminated with heavy metals and may pose a serious threat to the environment.
11
Content available remote Activity Networks with Delays an Application to Toxicity Analysis
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EN
ANDy, Activity Networks with Delays, is a discrete framework aiming at the qualitative modeling of time-dependent activities. The modular and expressive syntax makes ANDy suitable for a concise and natural modeling of time-dependent biological systems (i.e., regulatory pathways). Activities involve entities playing the role of activators, inhibitors or products of biochemical network operation. Activities may have a given duration, i.e., the time required to obtain results. An entity may represent an object (e.g., an agent, a biochemical species or a family of thereof) with a local attribute, a state denoting its level (e.g., concentration, strength). Entity levels may change as a result of an activity or may decay gradually as time passes by. The semantics of ANDy is formally given via high-level Petri nets ensuring this way some modularity. As main results we show that ANDy systems have finite state representations even for potentially infinite processes and it well adapts to the modeling of toxic behaviors. As an illustration, we present a classification of toxicity properties and give some hints on how they can be verified on ANDy systems with existing tools. A case study on blood glucose regulation is provided to exemplify the ANDy framework and the toxicity properties.
EN
Toxins produced by cyanobacteria (cyanotoxins) and released into water have become a serious problem worldwide due to the increasing morbidity and mortality of living organisms they have caused. The ability to synthesize the cytotoxic alkaloid cylindrospermopsin (CYN) has been demonstrated in several freshwater species of cyanobacteria. CYN is highly chemically stable under environmental factors and decomposes only under alkaline conditions, where it forms derivatives. The toxicity potential of the decomposition products formed at pH 10 combined with high temperature (100°C) or UV-B irradiation (36 μmol m−2 s−1) has been research based on the crustacean Thamnocephalus platyurus (Thamnotoxkit FTM) and bacteria Vibrio fischeri (Deltatox® II) bioassays. This paper is a continuation and completion of our previous experiments and the obtained results showed that the applied conditions contributed to the decomposition of the CYN molecule to non-toxic products and its structural modifications by separating the uracil ring or/and the sulfate group from the tricyclic guanidine moiety, leading to a reduction in its toxicity. To the best of our knowledge, this is the first report describing the toxicity of CYN decomposition products formed under alkaline conditions combined with boiling temperature or UV-B irradiation.
13
Content available remote L-kanawanina – niebiałkowy aminokwas toksyczny dla zwierząt i roślin
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EN
Allelopathy describes plant-plant interaction by chemicals released into environment. In most cases negative effect of allelochemicals is detected due to their toxicity. L- canavanine belongs to the group of non-protein amino acids, and is known as antimetabolite of L-arginine. L-canavanine is synthesized in legumes. It functions as a putative source of nitrogen, and is famous for its insecticidal activity. The work summarizes the current knowledge on the role of L-canavanine in plant metabolism and their impact on growth and development of plants. A special attention was pointed also on L-canavanine in plant-herbivore interaction.
EN
A contemporary family bears the consequences of the universal affirmation of individualism, laxism and consumerism. Consequently, alternatives for the home are boldly searched for, demolishing at the same time the traditional social order. The author discusses the most disturbing interfamilial phenomena associated with relationships. These are: the tendencies to compete; aggressive interactions; lack of desired mutual cross-references because of absence; individualism; superficiality of interactions between members of the household; inadequate communication in the family house; the growing manipulation in mutual relations; interactions resulting from co-addiction; “insulation relationships”; mediatization of mutual interpersonal relationships; interactions resulting from the permutations of roles in the family and toxic relationships as a result of atrophy of the family bonds. The article concludes with a proposal of a remedial program.
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EN
Objectives: The objective of this study was to assess the pattern and outcome of acute cholinesterase inhibitors substances (CIS) poisoning cases, in a cohort from a regional tertiary care hospital. Methods: cases admitted in the Toxicology Clinic of “Sf. Spiridon” Emergency Clinic Hospital Iasi, Romania between 1983 and 2013 were studied. Results: a total number of 606 patients were included. The reason for exposures was intentional in 70% of cases and the commonest route of poisoning was oral in 92.2%. The highest percent of cases was females (56.4), the age group 20-29 (25.4%) and the majority (66.7%) coming from rural areas, 28.2% being agricultural workers. 36.6% of cases were severe clinical forms. Overall mortality rates were 3.8%, more than half of the death patients (65.2%) had concomitant alcohol intake. It was a significant statistical association between decrease level of serum cholinesterase on admittance and severe forms (p 0.000) and between survival and deaths groups (p 0.000). The pattern of poisoning described by our retrospective study suggests that CIS poisoning are mainly preventable. The main effective goals for prevention are restriction in free accessibility to toxic pesticides, together with sustained efforts in education concerning the life-threatening danger of pesticide poisoning.
EN
Toxicity of the combustion engines is determined by means of the procedures that result from their size group and appropriation, determining a measurement mode (a type of test) and a calculation method, and lead to the determination of the so-called unit emissions of the particular components. The paper aims at presenting the differences in the unit emission value determined for a compression-ignition engine complying with the full procedure which includes the corrections resulting from a state of atmosphere and a type of the component observed, and are calculated in a simplified way omitting corrections.
17
Content available Cytotoxic Test of Octopus cyanea Ink Extract
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EN
Marine biodiversity of Papua is very high, but unfortunately research and utilization in medicine are limited. Many species of flora and fauna are used in ethopharmacology as drugs but without scientific explanation, e.g. octopus (Octopus cyanea), found in the Northern Papua Sea. The aim of this research was to test the toxicity of the ethanol octopus ink. The toxicity was tested with the Brine Shrimp Lethality Test (BSLT) method. The samples were collected from the sea of Biak island in West Papua, extracted with ethanol, ethyl acetate, and dichloromethane then tested the toxicity for Artemia salina leach larvae. The toxicity test involved concentrations of 1000, 750, 500, 250, 100, 75, 50, and 25 ppm. The result showed that ethanol extract of octopus ink has LC50 of 290 ppm, ethyl acetate extract has LC50 of 947 ppm, whereas dicholoromethane extract – 2190 ppm.
EN
Despite the wide application of gadolinium as a contrast agent for magnetic resonance imaging (MRI), there is a serious lack of information on its toxicity. Gadolinium and gadolinium oxide (Gd-oxide) are used as contrast agents for magnetic resonance imaging (MRI). There are methods for reducing toxicity of these materials, such as core nanoparticles coating or conjugating. Therefore, for toxicity evaluation, we compared the viability of commercial contrast agents in MRI (Gd-DTPA) and three nanoparticles with the same core Gd2O3 and small particulate gadolinium oxide or SPGO (< 40 nm) but different coatings of diethyleneglycol (DEG) as Gd2O3-DEG and methoxy polyethylene glycol-silane (mPEG-silane: 550 and 2000 Dalton) as SPGO-mPEG-silane550 and SPGO-mPEG-silane2000, respectively, in the SK-MEL3 cell line, by light microscopy, MTT assay using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide, and the LDH assay detecting lactate dehydrogenase activity. The viability values were not statistically different between the three nanoparticles and Gd-DTPA. The MTT and LDH assay results showed that Gd2O3-DEG nanoparticles were more toxic than Gd-DTPA and other nanoparticles. Also, SPGO-mPEG-silane2000 was more biocompatible than other nanoparticles. The obtained results did not show any significant increase in cytotoxicity of the nanoparticles and Gd-DTPA, neither dose-dependent nor time-dependent. Therefore, DEG and PEG, due to their considerable properties and irregular sizes (different molecular weights), were selected as the useful surface covering materials of nanomagnetic particles that could reveal noticeable relaxivity and biocompatibility characteristics.
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EN
Spent of water based mud (WBM) were tested in this study. Bioassays were done on spent WBM, brine after filtration and solid phase (SP) after filtration on the press. As test organisms, green algae Kirchneriella obesa and Botrydium granulatum were used, along with the cladoceran Simocephalus vetulus and the plant Lepidium sativum. Electrolytic conductivity was between 6.43 and 240 mS/cm. The liquid phase was toxic for K. obesa in the range of dilutions between 0.21 and 0.019, considered as LC50. The parameter LC50 in the category of dilutions was 0.125 to 0.0078 SPP for S. vetulus, 0.25 to 0.094 SPP for green alga Botrydium granulatum when diluted by brown soil and 0.56 to 0.039 SPP for Lepidium sativum. Maximum quantum efficiency (QY) of plants’ photosystem II (PS II), growing on mixtures of drilling fluids with soil, did not depend on the kind of drilling fluid, whereas minimal fluorescence (F0) did. Rinsing the salt out of drilling fluids in a 1:1 proportion was effective only for bentonite mud in the test with L. sativum.
20
Content available remote Toksyczność nanocząstek metali : wybrane zagadnienia
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PL
W najbliższych latach planowanego rozwoju nanotechnologii spodziewany jest wzrost narażenia na nanocząstki metali. Dane dotyczące toksyczności nanocząstek, chociaż niejednokrotnie sprzeczne są na tyle niepokojące, że są one postrzegane jako jedno z głównych, nowych zagrożeń dla zdrowia pracowników. W artykule przedstawiono wybrane zagadnienia dotyczące toksyczności nanocząstek metali.
EN
A review, with 36 refs., of respiratory, transdermal and gastro-intestinal hazards connected with the presence of metal nanoparticles in the work environment.
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