ABSTRACT
Objective To determine the electrical conductivity of cerebrum, liver, lung and muscle of rats at different postmortem intervals for investigating the relationship between EC and PMI. Methods Healthy Sprague-Dawley rats were sacrificed and kept at constant temperature of 25°C. Cerebrum, lung, liver and muscle were extracted at different PMIs of immediate (0d), 1d, 2d, 3d, 4d, 5d, 6d and 7d, and their extraction liquids were prepared with ultrapure water at the ratio of 1g:10mL. EC were separately determined for different tissues and organs. The relationships between EC of different tissues and organs and PMI were analyzed and their regression functions were established. The characteristics of EC values for four tissues and organs were compared and their decomposition processes were discussed. Results EC of brain and muscle showed no significant changes within 1d, and increased rapidly during 2~7d; but EC of liver and lung started to increase within 1d and increased rapidly during 2~7d.The relationship between EC of different tissues and organs and PMI were well fitted with cubic equations and liver gained the highest coefficient (R2=0.96). Additional, the EC of four organs presented various increasing laws in different periods of PMI. Conclusion The EC of cerebrum, lung, liver and muscle of rats were well fitted with PMI and the determination of EC of cadaver tissues can be expected to become an effective method for PMI estimation in forensic practice.
ABSTRACT
An automated on-line solid phase extraction-liquid chromatography-tandem mass spectrometry ( on-line SPE-LC-MS/MS ) method for the simultaneous quantification of six endogenous phytohormones including abscisic acid ( ABA ) , indole-3-acetic acid ( IAA ) , salicylic acid ( SA ) , jasmonic acid ( JA ) , indole-3-propionic acid ( IPA) and indole-3-butyric acid ( IBA) in rice tissues was described. Plant samples were extracted with methanol and on-line SPE procedure was performed with C18 SPE cartridges. Analytes were eluted to C18 analytical column with mobile phase and further analyzed by LC-MS/MS. The performance of the method was fully validated. Linearity showed good correlation (R2≥0. 99). Limits of detections (S/N=3) were in the range of 0. 1-0. 8 μg/kg. Recoveries varied between 71. 2% and 126%. The method was rapid and sensitive to determine multiple phytohormones in rice young panicles and the results were cross-validated with the off-line SPE-LC-MS/MS phytohormone analytical method. Finally, the method was applied to monitor the changes of ABA, IAA, SA and JA in wounded rice leaves. The trends were in accord with plant physiological processes.
ABSTRACT
An on-line solid phase extraction ( SPE ) coupled with HPLC-MS/MS method was developed to determine S-ammuxetine and R-ammuxetine in rat plasma. The sample preparation consisted of the following steps:A protein precipitation extraction used methanol and acetonitrile ( 50:50 , V/V ); an on-line SPE treatment to remove most matrixes in plasma;an enrichment and separation step used a C18 analytical column. S-and R-ammuxetine were determined by tandem mass spectrometry. The SPE column was a Retain PEP Javelin (10 mm × 2. 1 mm × 5 μm), while the chromatographic separation was achieved using a ZORBAX SB-C18 (50 mm × 2. 1 mm × 3. 5 μm) analytical column with an isocratic mobile phase composed of acetonitrile-water-formic acid (40:60:0. 1, V/V/V, 0. 3 mL/min). The selected reaction monitoring mode of the positive ion was performed and the precursor to the product ion transitions of m/z 292 . 1/154 . 0 and m/z 260. 4/116. 2 were used to measure S-ammuxetine, R-ammuxetine and internal standard (propranolol). The method was linear over a concentration range from 0 . 2 to 1000 μg/L with the correlation coefficients of 0 . 9903 and 0 . 9951 . The average intra-day precision values were 1 . 2% -12 . 0% for S-ammuxetine and 0. 4%-11. 2% for R-ammuxetine, respectively. The average recoveries were 94. 2%-101. 6% for S-ammuxetine and 94. 3% -109. 4% for R-ammuxetine. Compared to the literature, the sensitivity of this method increased dramatically. The present method has been successfully applied to the preclinical rat research of ammuxetine isomers following intragastric administration.
ABSTRACT
Objective To study the effect of the compatibility on treating Ⅱ toⅢphase pressure sore of senior citizen by auricularia in-depth fermentation extracts and the dimethyl acrylyl hydropathic compress.Methods A total of 60 patients with Ⅱto Ⅲ phase pressure sore were divided randomly into the expedmental group and the control group with 30 cases in each group.The experimental group(30 cases.50 pressure sores)were treated with the auricularia in--depth fermentation extracts and the dimethyl acrylyl hydropathic compress.The control group(30 case8,46 pressure sores)were treated with conventional methods of dressing change,0.5% iodine to disinfect the wound surface.then bounded it up with the aseptic vaseline yarn and the sursical dressing.The curative effect Was compared by observing the effect indicators.Results The response rate of the experimental group was 100.0%.with an average healing time of 10.33 d.For the control group.the response rate was 78.3%,the average healing time Was 24.27 d.There Was significant difference on efficiency and the average healing time between the two groups,P<0.01.Conclusions Auricularia in-depth fermentation extracts and the dimethyl acrylyl hydropathic compress to treat the senior citizen Ⅱ toⅢphase pressure gore with a view to easy.safe and economical characteris tic.has a significant effect on the new agricultural co-medical health care and community groups.