Canine mammary tumors (CMT) are very common in female dogs, representing approximately 50% of all tumors in this species, but are highly uncommon in male dogs and are primarily related to hyperestrogenism. There is co...Canine mammary tumors (CMT) are very common in female dogs, representing approximately 50% of all tumors in this species, but are highly uncommon in male dogs and are primarily related to hyperestrogenism. There is considerable scientific interest in the possible role of environmental contaminants in the etiology of mammary tumors, specifically in relation to synthetic chemical substances released into the environment to which living beings are either directly or indirectly exposed. In this study, the presence of pyrethroid insecticide was observed in adipose tissue adjacent to canine mammary tumors. High Precision Liquid Chromatography—HPLC was adapted to detect and identify environmental contaminants in adipose tissue adjacent to malignant mammary tumor in one male dog, Akita, 12 years old. After surgery, the mass was carefully examined for malignant neoplastic lesions. Five grams of adipose tissue adjacent to the tumor was collected to detect environmental contaminants. The pyrethroid was identified as tetramethrin, at 0.20 μg/g. This is the first report in which the environmental contaminant level was detectable in adipose tissue of this male dog with a malignant mammary tumor, by HPLC. Results suggest the possible involvement of pyrethroid in the canine mammary tumor carcinogenesis since this animal did not present any other tumor that could cause hyperestrogenism.展开更多
The synchronous fluorescence spectrometry was used for the first time to eliminate the interference between the emission of the small-molecule drugs and the determination of the endogenous fluorescence of the protein....The synchronous fluorescence spectrometry was used for the first time to eliminate the interference between the emission of the small-molecule drugs and the determination of the endogenous fluorescence of the protein.The synchronous fluorescence spectrometry and UV-Vis were applied to study the interaction between Tetramethrin and BSA in physiological buffer(pH 7.4).The results of the experiment proved that the quenching mechanism of fluorescence of BSA by Tetramethrin was a static quenching procedure.The number of binding potential point(n) and the association constant(K0) at 298K were n=1.13 and K0=1.428×105L·mol-1,respectively.The enthalpy change and the entropy change were calculated to be △H=29.69KJ·mol-1,△S=211.65J·K·mol-1,which showed that the binding mode was mainly the reflection of the hydrophobic interaction.On the basis of the Frster’s non-radiative energy transfer mechanism,the binding distance(r) and the rate of energy transfer(E)between donor(BSA) and acceptor(Tetramethrin) were obtained to be r=5.15nm,E=0.117,respectively.展开更多
文摘Canine mammary tumors (CMT) are very common in female dogs, representing approximately 50% of all tumors in this species, but are highly uncommon in male dogs and are primarily related to hyperestrogenism. There is considerable scientific interest in the possible role of environmental contaminants in the etiology of mammary tumors, specifically in relation to synthetic chemical substances released into the environment to which living beings are either directly or indirectly exposed. In this study, the presence of pyrethroid insecticide was observed in adipose tissue adjacent to canine mammary tumors. High Precision Liquid Chromatography—HPLC was adapted to detect and identify environmental contaminants in adipose tissue adjacent to malignant mammary tumor in one male dog, Akita, 12 years old. After surgery, the mass was carefully examined for malignant neoplastic lesions. Five grams of adipose tissue adjacent to the tumor was collected to detect environmental contaminants. The pyrethroid was identified as tetramethrin, at 0.20 μg/g. This is the first report in which the environmental contaminant level was detectable in adipose tissue of this male dog with a malignant mammary tumor, by HPLC. Results suggest the possible involvement of pyrethroid in the canine mammary tumor carcinogenesis since this animal did not present any other tumor that could cause hyperestrogenism.
文摘The synchronous fluorescence spectrometry was used for the first time to eliminate the interference between the emission of the small-molecule drugs and the determination of the endogenous fluorescence of the protein.The synchronous fluorescence spectrometry and UV-Vis were applied to study the interaction between Tetramethrin and BSA in physiological buffer(pH 7.4).The results of the experiment proved that the quenching mechanism of fluorescence of BSA by Tetramethrin was a static quenching procedure.The number of binding potential point(n) and the association constant(K0) at 298K were n=1.13 and K0=1.428×105L·mol-1,respectively.The enthalpy change and the entropy change were calculated to be △H=29.69KJ·mol-1,△S=211.65J·K·mol-1,which showed that the binding mode was mainly the reflection of the hydrophobic interaction.On the basis of the Frster’s non-radiative energy transfer mechanism,the binding distance(r) and the rate of energy transfer(E)between donor(BSA) and acceptor(Tetramethrin) were obtained to be r=5.15nm,E=0.117,respectively.
