Biological effects of power frequency magnetic fields: Neurochemical and toxicological changes in developing chick embryos

BACKGROUND: There are several reports that indicate a linkage between exposure to power frequency (50 – 60 Hz) magnetic fields with abnormalities in the early embryonic development of the chicken. The present study was designed to understand whether power frequency electromagnetic fields could act as an environmental insult and invoke any neurochemical or toxicological changes in developing chick embryo model. METHODS: Fertilized chicken eggs were subjected to continuous exposure to magnetic fields (50 Hz) of varying intensities (5, 50 or 100 μT) for a period of up to 15 days. The embryos were taken out of the eggs on day 5, day 10 and day 15. Neurochemical (norepinephrine and 5-hydroxytryptamine) and amino acid (tyrosine, glutamine and tryptophan) contents were measured, along with an assay of the enzyme glutamine synthetase in the brain. Preliminary toxicological investigations were carried out based on aminotransferases (AST and ALT) and lactate dehydrogenase activities in the whole embryo as well as in the liver. RESULTS: The study revealed that there was a significant increase (p < 0.01 and p < 0.001) in the level of norepinephrine accompanied by a significant decrease (p < 0.01 and p < 0.001) in the tyrosine content in the brain on day 15 following exposure to 5, 50 and 100 μT magnetic fields. There was a significant increase (p < 0.001) in glutamine synthetase activity resulting in the significantly enhanced (p < 0.001) level of glutamine in the brain on day 15 (for 100 μT only). The possible mechanisms for these alterations are discussed. Further, magnetic fields had no effect on the levels of tryptophan and 5-hydroxytryptamine in the brain. Similarly, there was no effect on the activity of either aminotransferases or lactate dehydrogenase in the whole embryo or liver due to magnetic field exposure. CONCLUSIONS: Based on these studies we conclude that magnetic field-induced changes in norepinephrine levels might help explain alterations in the circadian rhythm, observed during magnetic field stress. Also, the enhanced level of glutamine can act as a contributing factor for developmental abnormalities

Synthesis and antimicrobial activity of 2-substituted-6-chloro-8-nitro-4-trichloromethyl-4<i>H</i>-1,3,2-benzodioxaphosphorin 2-oxides

317-320A series of 2-aryloxy/2-arylthio-6-chloro-8-nitro-4-trichloromethyl-4H-1,3,2-benzodioxaphosphorin 2-oxides 3 have been synthesized by-reacting 2-(2,2,,2-trichloro-1-hydroxyethyl)-4-chloro-6-nitrophenol 1 with different arylphosphorodichloridates 2 in the presence of triethylamine at 70-80°C. Some of these compounds are prepared by reacting the monochloride, 2-chloro- 6-chloro-8-nitro-4-trichloromethyl-4H-1, 3, 2-benzodioxaphosphorin 2-oxide 4, in situ with substituted phenol and thiols 5. The monochloride is prepared by condensing 2-(2,2,2-trichloro-1-hydroxyethyl)- 4-chloro-6-nitrophenol with phosphorus oxychloride. IR, 1H, 13C and 31P NMR and mass spectral data have been discussed. Some of these compounds have been screened for their antibacterial and antifungal activities

Synthesis and antimicrobial activity of 2-aryloxy-2,3-dihydro-5-propylthio-1<i style="mso-bidi-font-style:normal">H</i>-1,3,2- <span style="font-size:12.0pt;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";mso-ansi-language:EN-IN;mso-fareast-language: EN-IN;mso-bidi-language:AR-SA" lang="EN-IN">benzodiazaphosphole 2-oxides</span>

735-7382-Aryloxy-2,3-dihydro-5-propylthio-1<i style="mso-bidi-font-style: normal">H-1,3,2-benzodiaza-phosphole 2-oxides <b style="mso-bidi-font-weight: normal">3 are synthesized by reacting equimolar quantities of 4-propylthio-1,2-phenylenediamine 1 with different arylphosphorodichloridates in the presence of triethylamine at 60- 70°C. IR, 1H, 13C and 31P NMR spectral data are discussed. All of these compounds have been screened for their antifungal and antibacterial activities.</span

Viability of unstimulated lymphocytes exposed to extremely low frequency electromagnetic fields is dependent on intensity

The cell viability and DNA damage in unstimulated sheep primary lymphocytes subjected to different extremely low electromagnetic field intensities (5, 50 and 100 µT; 50 Hz) were studied with special emphasis on apoptosis. Sheep primary lymphocytes cultured in RPMI, supplemented with 10% FBS in the absence of mitogens, were exposed till 16 h. The cell viability assessment by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay showed a dose dependent enhancement of viability at 16 h. Further, quantitative DNA laddering and flow cytometric analysis showed a significant decrease in apoptosis of the cells subjected to 100 (

Viability of unstimulated lymphocytes exposed to extremely low frequency electromagnetic fields is dependent on intensity

The cell viability and DNA damage in unstimulated sheep primary lymphocytes subjected to different extremely low electromagnetic field intensities (5, 50 and 100 µT; 50 Hz) were studied with special emphasis on apoptosis. Sheep primary lymphocytes cultured in RPMI, supplemented with 10% FBS in the absence of mitogens, were exposed till 16 h. The cell viability assessment by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay showed a dose dependent enhancement of viability at 16 h. Further, quantitative DNA laddering and flow cytometric analysis showed a significant decrease in apoptosis of the cells subjected to 100 (

Synthesis and bioactivity of some new 2-substituted-3,4-dihydro-3-(3'-chloro-4'-fluorophenyl)-2<i style="">H</i>-[1,3,2]benzoxaza­phosphorin 2-oxides

2171-2177Synthesis, spectral analysis and bioactivity of the title compounds have been described. The structures of these compounds are confirmed by analytical and spectral (IR, 1H, 13C, 31P NMR and mass) data. They show significant antimicrobial and insecticidal activity. They promote growth of the phosphate solubilizing bacteria in the soil without any toxic effect on the host tissue

Synthesis and TGA evaluation of novel triphosphate esters

Several new substituted organo tri/thiotriphosphate esters were synthesized by condensing cyclic oxaza/dioxaphosphorochloridates/thiochloridates with [K.sub.2]HP[O.sub.4] in the presence of tetrabutylammonium iodide. The functionality on the phosphate was systematically changed by synthesis, thus allowing evaluation and comparison of a range of phosphate esters with highly varied structural features. They were subjected to thermogravimetric analysis, derivative thermogravimetric analysis, and differential thermal analysis to assess their thermal stability and potential use as flame retardants. It has been found that their thermal degradations, being highly complex and dependent upon a number of molecular structural features, are difficult to rationalize on simple rules