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This review summarizes our knowledge of analogs and derivatives of diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A), the most extensively studied member of the dinucleoside 5',5"'-P1,Pn-polyphosphate (NpnN) family. After a short discussion of enzymes that may be responsible for the accumulation and degradation of Np4N's in the cell, this review focuses on chemically and/or enzymatically produced analogs and their practical applications. Particular attention is paid to compounds that have aided the study of enzymes involved in the metabolism of Ap4A (Np4N'). Certain Ap4A analogs were alternative substrates of Ap4A-degrading enzymes and/or acted as enzyme inhibitors, some other helped to establish enzyme mechanisms, increased the sensitivity of certain enzyme assays or produced stable enzyme:ligand complexes for structural analysis.
We report the synthesis, photochemical and photophysical properties and preliminary studies on biological effect of a new tritolylporphyrin dimer (T-D). Absorption and emis­sion properties of T-D suggest its possible use in photodynamic therapy. T-D is capable of singlet oxygen production with 0.8 quantum yield. It also has a high photostability. The photodynamic properties of the dimer were examined following the growth of SKMEL 188 (human melanoma) cells irradiated with red light (cut off < 630 nm). The surviving frac­tion of the cells decreased about 3-fold (us. non-irradiated cells) for an 81 J/cm dose. Our results suggest that tritolylporphyrine dimer T-D may be an interesting hydrophobic sensitizer for photodynamic therapy.
Nigella sativa is an annual flowering plant, native to Iran and other parts of southwest Asia, belonging to the buttercup family (Ranunculaceae). Its grain has several important health-related properties such as anti-parasitic, anti-virus, anti-bacterial, increased milk production, carminative, and anti-diabetic. To determine effects of fertilizer treatments on this plant, this experiment was conducted in randomized complete block design in three replications with seven treatments. Fertilizer treatments consisted of Bio phosphor (B 2 kg∙ha-1), Bio sulphur (S 5 kg∙ha-1), Biological fertilized phosphate BAVAR 2 (F 100 g∙ha-1), chemical fertilizer (M) according to soil analysis, and combined fertilizer (B+S), (S+F), and (C) treatment. The application of fertilizers showed a significant effect (p<0.01) on plant height, number of capsules per plant, seed weight, grain yield (g/m-2), number of flowers per plant, and biological yield (g/m-2). There were no observed significant differences (p<0.01) on the number of seeds per capsule, seed weight and yield between chemical fertilizer and biological BARVAR 2. Thus, it can be concluded that there is no preventative for biological fertilizer to produce a good yield of biological product for human health.
The effects of exposure to a 900 MHz electromagnetic field (EMF) on the serum cortisol and triiodothyronine-thyroxin (T₃-T₄) levels in adult male Syrian hamsters were evaluated. Seventy two hamsters were used in three independent groups: 24 served as controls (without exposure to stress and EMF), 24 were exposed to a 900 MHz EMF for 10 d, and 24 were exposed to a 900 MHz EMF for 50 d. The exposures were performed 1 h/d to a 900 MHz EMF emitted by cellular phones. The levels of cortisol and T₃-T₄ were measured by using an immunoradiometric assay (IRMA) method. The results revealed the cortisol values of the group, which was exposed to 900 MHz EMF for 50 d, were higher than those of the other groups (P<0.01). The levels of T₃ in the control group were higher than that of the long-term exposure group (P<0.01), and levels of T₄ in the 900 MHz EMF group for the long-term and short-term exposure groups, were higher than that of the control group (P <0.01). These results indicate that a 900 MHz EMF emitted by cellular phones, especially in the case of long-term exposure, increased the serum cortisol and T₄ levels and decreased the T₃ level, and suggest that it can destroy the endocrine system in general.
W pracy badano efekty ostrego i 10-dniowego podawania ip alkaloidów benzofenantrydynowych, tj. chelidoniny i sangwinaryny na aktywność aminotransferaz (ALT i AST) oraz oznaczano poziom a-fetoproteiny (AFP) i ß2-mikroglobuliny w surowicy krwi szczurów. Wykazano, że ostre, bądź 10-dniowe podanie chelidoniny nie wpływało na aktywność obu badanych aminotransferaz. Sangwinaryna podana w dawce 0,1 LD50 jednorazowo nie zmieniała aktywności ALT, ale istotnie zmniejszała aktywność AST. Natomiast zastosowana przez 10 dni istotnie zwiększała aktywność AST we wszystkich stosowanych dawkach. Uzyskane podwyższenie aktywności aminotransferaz w surowicy krwi szczurów poddanych działaniu sangwinaryny może sugerować hepatotoksyczne działanie tego alkaloidu. Oba badane alkaloidy zarówno po jednorazowym, jak też 10-dniowym podaniu, nie wpływały na poziom AFP i ß2-mikroglobuliny w surowicy krwi szczurów.
The three-dimensional conformation of Aea-TMOF (Aedes aegypti Trypsin Modulating Oostatic Factor), a decapeptide (YDPAPPPPPP) isolated from mosquito ovaries that inhibits the translation of many trypsin-like serine proteases, e.g. in mosquitoes, flies and lepidopterans, was used as a model for the synthesis of 10 aromatic and aliphatic organic acid and ester analogues. The organic TMOF analogues were tested against herbivorous pest lepidopterans and larval Ae. aegypti. The compounds administered to microtiter plates or to leaf disks caused mortality to mosquito larvae and the diamondback moth, Plutella xylostella, larvae 3-6 days after treatment. The surviving diamondback moth larvae were sluggish, immobile and stopped feeding. A biochemical analysis showed that in larval P. xylostella the trypsin activity was low and correlated with the observed mortality. No activity was found against Heliothis virescens when four of the synthetic compounds that affected P. xylostella and Ae. aegypti were tested, although the decapeptide, TMOF, does affect trypsin biosynthesis in H. virescens.
Objective: The biological effects of variable magnetic fields (MF) generated by widely used electrical devices on living organisms are not well understood. However MF may be potentially hazardous for pregnant women, this problem was not profoundly studied. The aim of this study was to evaluate the influence of the variable magnetic field (MF) on the placental metabolism by measurement of glucose consumption and lactate production in the human placenta under dual recirculating perfusion conditions. Material and methods: Altogether 20 term human placental cotyledons were exposed to homogeneous variable MF of B = 2 mT and f = 50 Hz (n=10; group E,) or of B = 5 mT and f = 50 Hz (n=10; group E2) during 3 hours dual close perfusion in vitro. 10 term placental cotyledons were perfused without an exposure to the MF and they served as a control group. Results: The results showed no effect of used MF on the glucose consumption either in group E, or in group E2in. There was also no influence of MF on lactic acid production in group Er In group E2, however, a significant increase of lactic acid production in the fetal circulation from 90lh to 180th minute and in the maternal circulation at 180 minute was noted. Conclusions: An increase in the lactic acid production in the group E2in observed during the experiment may result from hindered oxygen supply to the placenta and intensified anaerobic metabolism of glucose.
The behavioural effect of trans,trans-farnesol and its structural derivatives on M. persicae was evaluated. The incorporation of carboxy group into the molecule did not alter the strong deterrent activity of farnesol. The lactonization and the epoxidation of farnesol caused the delay in expression and the loss of deterrent activity, respectively. The ester, product of Claissen rearrangement of farnesol and iodolactone did not exhibit significant biological effect.
This review describes the structure, physicochemical properties and sources of asbestos as well as other mineral fibres in the natural environment. The diversity of character and methods for the determination of airborne inorganic fibres are discussed with particular attention to the biological effects on humans health. It also demonstrates the practical significance of asbestos.
Pea and lentil seeds were exposed to 125, 250 mT magnetic field. Total weight, stem weight, total and stem length were measured after 7 and 14 days of exposure. Growth parameters of these seeds were increased; consequently, seedlings from seeds magnetically treated grew taller and heavier than controls. These differences were highly significant for 24 hour (D5, D11) and chronic exposure (D6, D12). An increase in both weight and length of pea and lentil plants was observed with respect to control groups, yielding significant differences in the 14-day group (p<0.001) for every parameter. Increased root development was also observed.
The fact that men and women are living longer than they have ever done before is something in which we can all rejoice. However, the process of ageing is associated with changes in skeletal, muscular, gastrointestinal, neural hormonal and metabolic processes that seriously affect an individual's performance and quality of life. Indeed, such changes can be contributory to a loss of independence in the elderly. This state-of-the art address highlights the main changes found to occur with ageing whilst simultaneously reporting findings of in vivo and in vitro studies designed to elucidate the potential of the Krebs cycle intermediate - alpha-ketoglutaric acid (AKG) in protecting elderly body systems from failing and degradation. The topics of paramount importance include impaired bone structure and strength, amino acid and mineral absorption, muscle performance, as well as highlighting the role of Krebs cycle intermediates in the debilitating changes that occur with end-stage renal failure and the regulation of the lipid metabolism. Finally, focus will be given to the role of 2-oxoglutarate as a potent protective factor in connection with the development of malignant cells in the body.
The Algerian west coast is the prime recipient ofsev eral forms of pollution; hence, the necessity for an impact assessment of this coastal pollution using a suite ofr ecommended marine biomarkers, including lysosomal membrane stability in living cells by the Neutral Red Retention Time (NRRT) method, the evaluation ofmicron ucleus (MN) frequency, and the determination ofacet ylcholinesterase (AChE) activity in mussels Mytilus galloprovincialis, sampled from the large, polluted Oran Harbour (OH) and the Maˆarouf( Mrf) marine mussel farm between July 2005 and April 2006. The difference in the variations oft he annual physical parameters between OH and Mrfco rresponds to the influence ofthe domestic and industrial sewage discharged by the city ofO ran. The biological data ofthe mussels (condition index, protein content) recorded at both sites were related to their natural reproductive cycle. This indicated that intrinsic variation between the sites due to different mussel development phases was minimal. The variation in the AChE activity of some organs ofO H and Mrfm ussels, with minimal inhibition in July and a higher NRRT recorded in the granular haemocytes in the Mrfthan in the OH mussels during the autumn and spring, depends on the quality ofthe biotope and on generic stress factors. Moreover, the variation in MN frequency, in general reflecting a non-significant seasonal and spatial genotoxic effect ofthe contamination at the two sampling sites, requires further investigations regarding biotic and abiotic variations.
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